Science.gov

Sample records for aerosol imager cai

  1. Deriving High Resolution UV Aerosol Optical Depth over East Asia using CAI-OMI Joint Retrieval

    NASA Astrophysics Data System (ADS)

    Go, S.; Kim, J.; KIM, M.; Lee, S.

    2015-12-01

    Monitoring aerosols using near UV spectral region have been successfully performed over decades by Ozong Monitoring Instruments (OMI) with benefit of strong aerosol signal over continuous dark surface reflectance, both land and ocean. However, because of big foot print of OMI, the cloud contamination error was a big issue in the UV aerosol algorithm. In the present study, high resolution UV aerosol optical depth (AOD) over East Asia was derived by collaborating the Greenhouse gases Observing SATellite/Thermal And Near infrared Sensor for carbon Observation (GOSAT/TANSO)-Cloud and Aerosol Imager (CAI) and OMI together. AOD of 0.1 degree grid resolution was retrieved using CAI band 1 (380nm) by bring OMI lv.2 aerosol type, single scattering albedo, and aerosol layer peak height in 1 degree grid resolution. Collocation of the two dataset within the 0.5 degree grid with time difference of OMI and CAI less than 5 minute was selected. Selected region becomes wider as it goes to the higher latitude. Also, calculated degradation factor of 1.57 was applied to CAI band1 (380nm) by comparing normalized radiance and Lambertian Equivalent Reflectivity (LER) of both sensors. The calculated degradation factor was reasonable over dark scene, but inconsistent over cirrus cloud and bright area. Then, surface reflectance was developed by compositing CAI LER minimum data over three month period, since the infrequent sampling rate associated with the three-day recursion period of GOSAT and the narrow CAI swath of 1000 km. To retrieve AOD, look up table (LUT) was generated using radiative transfer model VLIDORT NGST. Finally, the retrieved AOD was validated with AERONET ground based measurement data during the Dragon-NE Asia campaign in 2012.

  2. Study on remote sensing of aerosols over land using TANSO-CAI

    NASA Astrophysics Data System (ADS)

    Zhong, Guosheng; Wang, Xiufeng; Yin, Shuai; Sun, Zhongyi; Tani, Hiroshi

    2016-04-01

    The Cloud and Aerosol Imager (CAI) is one of the subunits of observation instrument Thermal And Near-infrared Sensor for carbon Observation (TANSO) onboard the GOSAT, and is used to observe aerosol optical properties and clouds. TANSO-CAI includes 4 bands (370~390 nm, 668~688 nm, 860~880 nm and 1560~1680 nm), bands 1 to 3 have a 0.5-km spatial resolution at the nadir and 1000-km observation swath. The spatial resolution and swath of band 4 are 1.5 km and 750 km, respectively. In this study, it was assumed that the surface reflectance at 670 nm can be obatined using an empirical relationship between the reflectances at 670 nm and at 1600 nm. For analyzing the empirical relationship, dark fields were selected from the GOSAT-CAI data, where AERONET sun photometer measurements were available within 30 minutes, the distance from the AERONET station was within 30 km, and the AOD at 550 nm was below 0.1. The surface reflectance was derived by atmospheric correction with the Second Simulation of a Satellite Signal in the Solar Spectrum (6S) radiative transfer model and AERONET AOD. A regression function between top-of-atmosphere reflectances at 1600 nm and surface reflectances at 670 nm was summarized. AODs were retrieved using a look-up table method and compared with AERONET AODs. The results show that more than 70% validating data are located within expected errors for MODIS (±0.05 ±0.15τ, τ is AOD).

  3. Retrieval and Validation of Aerosol Optical Properties over East Asia from TANSO-Cloud and Aerosol Imager

    NASA Astrophysics Data System (ADS)

    Lee, Sanghee; Kim, Jhoon; Kim, Mijin; Choi, Myungje; Go, Sujung; Lim, HyunKwang; Ou, Mi-Lim; Goo, Tae-Young; Yokota, Tatsuya

    2015-04-01

    Aerosol is a significant component on air quality and climate change. In particular, spatial and temporal distribution of aerosol shows large variability over East Asia, thus has large effect in retrieving carbon dioxide from Greenhouse Gases Observing Satellite (GOSAT) Thermal And Near infrared Sensor for carbon Observation Fourier Transform Spectrometer (TANSO-FTS). An aerosol retrieval algorithm was developed from TANSO- Cloud and Aerosol Imager (CAI) onboard the GOSAT. The algorithm retrieves aerosol optical depth (AOD), size distribution of aerosol, and aerosol type in 0.1 degree grid resolution and surface reflectance was estimated using the clear sky composite method. To test aerosol absorptivity, the reflectance difference method was considered using channels of TANSO-CAI. In this study, the retrieved aerosol optical depth (AOD) was compared with those of Aerosol Robotic NETwork (AERONET) and MODerate resolution Imaging Sensor (MODIS) dataset from September 2011 and August 2014. Comparisons of AODs between AERONET and CAI show the reasonably good correlation with correlation coefficient of 0.77 and regression slope of 0.87 for the whole period. Moreover, those between MODIS and CAI for the same period show correlations with correlation coefficient of 0.7 ~ 0.9 and regression slope of 0.7 ~ 1.2, depending on season and comparison regions however, the largest error source in aerosol retrieval has been surface reflectance. Over ocean and some Land, surface reflectance tends to be overestimated, and thereby CAI-AOD tends to be underestimated. Based on the results with CAI algorithm developed, the algorithm is continuously improved for better performance.

  4. Validation of Retrieved Aerosol Optical Properties over Northeast Asia for Five Years from GOSAT TANSO-Cloud and Aerosol Imager

    NASA Astrophysics Data System (ADS)

    Kim, J.; Lee, S.; KIM, M.; Choi, M.; Go, S.; Lim, H.; Goo, T. Y.; Nakajima, T.; Kuze, A.; Shiomi, K.; Yokota, T.

    2015-12-01

    An aerosol retrieval algorithm was developed from Thermal And Near infrared Sensor for carbon Observation-Cloud and Aerosol Imager (TANSO-CAI) onboard the Greenhouse Gases Observing Satellite (GOSAT). The algorithm retrieves aerosol optical depth (AOD), size distribution of aerosol, and aerosol type in 0.1 degree grid resolution by look-up tables, which is used in retrieving optical properties of aerosol using inversion products from Aerosol Robotic NETwork (AERONET) sun-photometer observation. To improve the accuracy of aerosol algorithm, first, this algorithm considered the annually estimated radiometric degradation factor of TANSO-CAI suggested by Kuze et al. (2014). Second, surface reflectance was determined by two methods: one using the clear sky composite method from CAI measurements and the other the database from MODerate resolution Imaging Sensor (MODIS) surface reflectance data. At a given pixel, the surface reflectance is selected by using normalized difference vegetation index (NDVI) depending on season (Hsu et al., 2013). In this study, the retrieved AODs were compared with those of AERONET and MODIS dataset for different season over five years. Comparisons of AODs between AERONET and CAI show reasonable agreement with correlation coefficients of 0.65 ~ 0.97 and regression slopes between 0.7 and 1.2 for the whole period, depending on season and sites. Moreover, those between MODIS and CAI for the same period show agreements with correlation coefficients of 0.7 ~ 0.9 and regression slopes between 0.7 and 1.0, depending on season and regions. The results show reasonably good correlation, however, the largest error source in aerosol retrieval has been surface reflectance of TANSO-CAI due to its 3-days revisit orbit characteristics.

  5. Developing Large CAI Packages.

    ERIC Educational Resources Information Center

    Reed, Mary Jac M.; Smith, Lynn H.

    1983-01-01

    When developing large computer-assisted instructional (CAI) courseware packages, it is suggested that there be more attentive planning to the overall package design before actual lesson development is begun. This process has been simplified by modifying the systems approach used to develop single CAI lessons, followed by planning for the…

  6. CAI Terminal Characteristics.

    ERIC Educational Resources Information Center

    Braun, Peter

    The bewildering number of available terminals which are offered to CAI users presents a rather formidable problem of which one to choose. This article surveys what appear to be evolving standards for terminals. The usefulness of these terminals for CAI purposes is discussed, together with the best known prototype exhibiting the particular feature.…

  7. Carbon, CAIs and chondrules

    NASA Technical Reports Server (NTRS)

    Ash, R. D.; Russell, S. S.

    1994-01-01

    It has been shown that C is present in CAI's and chondrules. It can be distinguished from matrix C both by its thermal stability and isotopic composition, which implies that it was not introduced after parent body accretion. It is concluded that C must have been present in the chondrule and CAI precursor material. Therefore any models of chondrule and CAI formation and inferences drawn about solar system conditions during these events must take into account the consequences of the presence of C on inclusion chemistry, mineralogy, and oxidation state.

  8. Verification of new cloud discrimination algorithm using GOSAT TANSO-CAI in the Amazon

    NASA Astrophysics Data System (ADS)

    Oishi, Y.; Ishida, H.; Nakajima, T. Y.

    2015-12-01

    Greenhouse gases Observing SATellite (GOSAT) was launched in 2009 to measure the global atmospheric CO2 and CH4 concentrations. GOSAT is equipped with two sensors: the Thermal And Near-infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS) and the Cloud and Aerosol Imager (TANSO-CAI). The presence of clouds in the instantaneous field-of-view (IFOV) of the FTS leads to incorrect estimates of the concentrations. Thus, the FTS data which are suspected to be cloud-contaminated must be identified using a CAI cloud discrimination algorithm and rejected. Conversely, overestimation of clouds leads to reduce the amount of the FTS data which can be used to estimate the greenhouse gases concentrations. It becomes a serious problem in the region of tropical rainforest such as the Amazon, where there are very few remaining FTS data by cloud cover. The preparation for the launch of the GOSAT-2 in fiscal 2017 has been progressing. To improve the accuracy of estimates of the greenhouse gases concentrations, we need to refine the existing CAI cloud discrimination algorithm. For the reason, a new cloud discrimination algorithm using support vector machines (SVM) was developed. Visual inspections can use the locally optimized thresholds, though the existing CAI cloud discrimination algorithm uses the common thresholds all over the world. Thus, it is certain that the accuracy of visual inspections is better than these algorithms in the limited region without areas such as ice and snow, where it is difficult to discriminate between clouds and ground surfaces. In this study we evaluated the accuracy of the new cloud discrimination algorithm by comparing with the existing CAI cloud discrimination algorithm and visual inspections of the same CAI images in the Amazon. We will present our latest results.

  9. Feasibility of polarized all-sky imaging for aerosol characterization

    NASA Astrophysics Data System (ADS)

    Kreuter, A.; Blumthaler, M.

    2012-12-01

    Polarized all-sky distribution measurements contain radiative information about aerosol properties. We investigate the method of all-sky imaging for aerosol property retrieval and propose a technical frame work for image processing and analysis. Using Zernike polynomials, we decompose the relative Stokes parameter distributions, which efficiently captures the information content. The resulting feature vector is well suited for all-sky imaging, independent of calibration and robust against noise. It can be directly used in existing algorithms or alternative types of retrieval methods of aerosol optical properties in the future. By modeling possible aerosol scenarios we investigate the influence of different aerosol types in terms of the first two principal components describing the maximal variances. In this representation we show that the feature vector from a polarized all-sky imager is suitable for aerosol classification with respect to size and single scatter albedo.

  10. Skill Specific CAI Techniques.

    ERIC Educational Resources Information Center

    Lavine, Roberta Z.; Fechter, Sharon Ahern

    Advantages of computer-assisted instruction (CAI) for grammar-oriented exercises are considered, and a learning module to help the student prepare for the Test of English as a Foreign Language (TOEFL) exam is described. The exercises are modeled on the TOEFL exam: the student is given a sentence, one part of which is incorrect and is asked to…

  11. The Aerosol Limb Imager: acousto-optic imaging of limb scattered sunlight for stratospheric aerosol profiling

    NASA Astrophysics Data System (ADS)

    Elash, B. J.; Bourassa, A. E.; Loewen, P. R.; Lloyd, N. D.; Degenstein, D. A.

    2015-12-01

    The Aerosol Limb Imager (ALI) is an optical remote sensing instrument designed to image scattered sunlight from the atmospheric limb. These measurements are used to retrieve spatially resolved information of the stratospheric aerosol distribution, including spectral extinction coefficient and particle size. Here we present the design, development and test results of an ALI prototype instrument. The long term goal of this work is the eventual realization of ALI on a satellite platform in low earth orbit, where it can provide high spatial resolution observations, both in the vertical and cross-track. The instrument design uses a large aperture Acousto-Optic Tunable Filter (AOTF) to image the sunlit stratospheric limb in a selectable narrow wavelength band ranging from the visible to the near infrared. The ALI prototype was tested on a stratospheric balloon flight from the Canadian Space Agency (CSA) launch facility in Timmins, Canada, in September 2014. Preliminary analysis of the hyperspectral images indicate that the radiance measurements are of high quality, and we have used these to retrieve vertical profiles of stratospheric aerosol extinction coefficient from 650-1000 nm, along with one moment of the particle size distribution. Those preliminary results are promising and development of a satellite prototype of ALI within the Canadian Space Agency is ongoing.

  12. Aerosol retrieval using Gestationary Ocean Color Imager (GOCI)

    NASA Astrophysics Data System (ADS)

    Kim, J.; Lee, J.; Choi, M.

    2012-12-01

    Hourly aerosol properties in East Asia are retrieved from the first Geostationary Ocean Color Imager (GOCI) launched in June 2010 onboard the Communication, Ocean, and Meteorological Satellite (COMS). A multi-channel algorithm was developed to retrieve aerosol optical depth (AOD), fine-mode fraction (FMF), and aerosol type in 500m×500m resolution. To develop optimized algorithm for the target area of GOCI, optical properties of aerosol are analyzed from extensive observation of AERONET sunphotometers to generate lookup table. Surface reflectance of turbid water is determined from 30-day composite of Rayleigh- and gas corrected reflectance. By applying the present algorithm to top-of-the atmosphere reflectance, three different aerosol cases dominated by anthropogenic aerosol contains black carbon (BC), dust, and non-absorbing aerosol are analyzed to test the algorithm. The algorithm retrieves AOD, and size information together with aerosol type which are consistent with results inferred by RGB image in a qualitative way. The comparison of the retrieved AOD with those of MODIS collection 5 and AERONET sunphotometer observations shows reliable results. Especially, the application of turbid water algorithm significantly increases the accuracy in retrieving AOD at Anmyon station.

  13. Maxi CAI with a Micro.

    ERIC Educational Resources Information Center

    Gerhold, George; And Others

    This paper describes an effective microprocessor-based CAI system which has been repeatedly tested by a large number of students and edited accordingly. Tasks not suitable for microprocessor based systems (authoring, testing, and debugging) were handled on larger multi-terminal systems. This approach requires that the CAI language used on the…

  14. Detecting Thin Cirrus in Multiangle Imaging Spectroradiometer Aerosol Retrievals

    NASA Technical Reports Server (NTRS)

    Pierce, Jeffrey R.; Kahn, Ralph A.; Davis, Matt R.; Comstock, Jennifer M.

    2010-01-01

    Thin cirrus clouds (optical depth (OD) < 03) are often undetected by standard cloud masking in satellite aerosol retrieval algorithms. However, the Mu]tiangle Imaging Spectroradiometer (MISR) aerosol retrieval has the potential to discriminate between the scattering phase functions of cirrus and aerosols, thus separating these components. Theoretical tests show that MISR is sensitive to cirrus OD within Max{0.05 1 20%l, similar to MISR's sensitivity to aerosol OD, and MISR can distinguish between small and large crystals, even at low latitudes, where the range of scattering angles observed by MISR is smallest. Including just two cirrus components in the aerosol retrieval algorithm would capture typical MISR sensitivity to the natural range of cinus properties; in situations where cirrus is present but the retrieval comparison space lacks these components, the retrieval tends to underestimate OD. Generally, MISR can also distinguish between cirrus and common aerosol types when the proper cirrus and aerosol optical models are included in the retrieval comparison space and total column OD is >-0.2. However, in some cases, especially at low latitudes, cirrus can be mistaken for some combinations of dust and large nonabsorbing spherical aerosols, raising a caution about retrievals in dusty marine regions when cirrus is present. Comparisons of MISR with lidar and Aerosol Robotic Network show good agreement in a majority of the cases, but situations where cirrus clouds have optical depths >0.15 and are horizontally inhomogeneous on spatial scales shorter than 50 km pose difficulties for cirrus retrieval using the MISR standard aerosol algorithm..

  15. Estimation of aerosol optical properties from all-sky imagers

    NASA Astrophysics Data System (ADS)

    Kazantzidis, Andreas; Tzoumanikas, Panagiotis; Salamalikis, Vasilios; Wilbert, Stefan; Prahl, Christoph

    2015-04-01

    Aerosols are one of the most important constituents in the atmosphere that affect the incoming solar radiation, either directly through absorbing and scattering processes or indirectly by changing the optical properties and lifetime of clouds. Under clear skies, aerosols become the dominant factor that affect the intensity of solar irradiance reaching the ground. It has been shown that the variability in direct normal irradiance (DNI) due to aerosols is more important than the one induced in global horizontal irradiance (GHI), while the uncertainty in its calculation is dominated by uncertainties in the aerosol optical properties. In recent years, all-sky imagers are used for the detection of cloud coverage, type and velocity in a bouquet of applications including solar irradiance resource and forecasting. However, information about the optical properties of aerosols could be derived with the same instrumentation. In this study, the aerosol optical properties are estimated with the synergetic use of all-sky images, complementary data from the Aerosol Robotic Network (AERONET) and calculations from a radiative transfer model. The area of interest is Plataforma Solar de Almería (PSA), Tabernas, Spain and data from a 5 month period are analyzed. The proposed methodology includes look-up-tables (LUTs) of diffuse sky radiance of Red (R), Green (G) and Blue (B) channels at several zenith and azimuth angles and for different atmospheric conditions (Angström α and β, single scattering albedo, precipitable water, solar zenith angle). Based on the LUTS, results from the CIMEL photometer at PSA were used to estimate the RGB radiances for the actual conditions at this site. The methodology is accompanied by a detailed evaluation of its robustness, the development and evaluation of the inversion algorithm (derive aerosol optical properties from RGB image values) and a sensitivity analysis about how the pre-mentioned atmospheric parameters affect the results.

  16. A CAI in the Ivuna CI1 Chondrite

    NASA Technical Reports Server (NTRS)

    Frank, David R.; Zolensky, M.; Martinez, J.; Mikouchi, T.; Ohsumi, K.; Hagiya, K.; Satake, W.; Le, L.; Ross, D.; Peslier, A.

    2011-01-01

    We have recently discovered the first well-preserved calcium aluminum-rich inclusion (CAI) in a CI1 chondrite (Ivuna). Previously, all CI1 chondrites were thought to be devoid of preserved CAI and chondrules due to the near total aqueous alteration to which their parent body (bodies) have been subjected. The CAI is roughly spherical, but with a slight teardrop geometry and a maximum diameter of 170 microns (fig. 1). It lacks any Wark-Lovering Rim. Incipient aqueous alteration, and probably shock, have rendered large portions of the CAI poorly crystalline. It is extremely fine-grained, with only a few grains exceeding 10 microns. We have performed electron microprobe analyses (EPMA), FEG-SEM imaging and element mapping, as well as electron back-scattered diffraction (EBSD) and synchrotron X-ray diffraction (SXRD) in order to determine the fundamental characteristics of this apparently unique object.

  17. The Mars Imager for Cloud and Aerosol (MICA) instrument concept

    NASA Astrophysics Data System (ADS)

    Hipkin, V.; Drummond, J.; Hackett, J.; Besla, G.

    2004-05-01

    Cloud and dust play an important role in the Mars polar atmosphere. Of particular interest is the evolution of cap-edge dust storms observed during the Mars Global Surveyor mission, and the development of the polar hood and aphelion cloud band. This poster describes the Mars Imager for Cloud and Aerosol (MICA), a four-band visible camera designed to characterize Mars cloud and dust by imaging the limb at sunrise and sunset. MICA will be capable of producing profiles of Mars aerosol optical properties from 0-75km altitude with a vertical resolution better than 600m. The MICA design uses multiple bands and a new occulting disk technique to provide enhanced dust characterization capabilities. The full dynamic range of the camera is optimized for atmospheric scattered light. A pinhole in the occulting disk attenuates direct sunlight, reducing its intensity to levels produced by the atmospheric scattering. The resulting composite image contains both a detailed image of the sun and a sensitive wide-angle image of the distribution of thin cloud and aerosol layers. Absolute calibration is possible through viewing the sun at high angles above the atmosphere. The calibrated solar image produces particle extinction measurements directly, while the wide-angle part of the image can be used to fit the scattering phase function in the case of horizontally homoge-neous layers. These measurements will provide new constraints on Mars aerosol particle size distribution and optical properties. The addition of a flip mirror gives MICA the capability also to observe the surface. MICA was conceived as part of the MARVEL Scout proposal. It is intended that it will follow on from Mars Express and MRO cloud and aerosol vertical profile mapping, providing new information, higher vertical resolution and adding to the Mars cloud and dust climatology.

  18. Atmospheric aerosol profiling with a bistatic imaging lidar system.

    PubMed

    Barnes, John E; Sharma, N C Parikh; Kaplan, Trevor B

    2007-05-20

    Atmospheric aerosols have been profiled using a simple, imaging, bistatic lidar system. A vertical laser beam is imaged onto a charge-coupled-device camera from the ground to the zenith with a wide-angle lens (CLidar). The altitudes are derived geometrically from the position of the camera and laser with submeter resolution near the ground. The system requires no overlap correction needed in monostatic lidar systems and needs a much smaller dynamic range. Nighttime measurements of both molecular and aerosol scattering were made at Mauna Loa Observatory. The CLidar aerosol total scatter compares very well with a nephelometer measuring at 10 m above the ground. The results build on earlier work that compared purely molecular scattered light to theory, and detail instrument improvements. PMID:17514239

  19. Lung physiology and aerosol deposition imaged with positron emission tomography.

    PubMed

    Venegas, Jose; Winkler, Tilo; Harris, R Scott

    2013-02-01

    Physiological conditions and pathophysiological changes in the lungs may affect many applications in aerosol medicine and pulmonary drug delivery. In the diseased lung, spatial heterogeneity in function and structure may cause substantial changes in aerosol transport and local deposition among different lung regions. Non-uniform aerosol deposition affects airway or tissue pharmacological dosing, which could reduce the therapeutic effectiveness of inhalation therapy. This review article presents examples of pulmonary imaging using PET and PET-CT in lung physiology with an emphasis on their implications for aerosol medicine. Measurements of regional ventilation, perfusion, and ventilation/perfusion ratio, by imaging local kinetics of intravenously injected Nitrogen-13 in saline solution, and of pulmonary inflammation, by assessing the regional uptake of the radiotracer (18)F-FDG, are presented. These examples demonstrate that it is possible to access both preexisting conditions, such as heterogeneity of ventilation, perfusion, and/or inflammatory stimuli, which may affect inhalation therapy, and the functional effects of inhaled medications or inflammatory agents on lung regional function. The imaging techniques described could be efficient tools to evaluate quantitatively and noninvasively these processes in vivo. Furthermore, it can be expected that imaging of respiratory structure and function will yield sensitive biomarkers of disease, which will help and speed drug discovery, and the evaluation of novel inhalation therapies.

  20. Zr Isotope Systematics of Allende CAIs

    NASA Astrophysics Data System (ADS)

    Mane, P.; Romaniello, S. J.; Brennecka, G. A.; Williams, C. D.; Wadhwa, M.

    2014-09-01

    We report high precision Zr isotopic measurements of CAIs from Allende CV3 meteorite. Our results indicate a uniform Zr isotopic composition in the CAI forming region, with enrichment in r-process isotope 96Zr.

  1. Teacher's Handbook for CAI Courses.

    ERIC Educational Resources Information Center

    Suppes, Patrick; And Others

    The handbooks for the most widely used computer-assisted instruction (CAI) courses now available on computer terminals at the Institute for Mathematical Studies in the Social Sciences at Stanford University are presented. Handbooks are included for the following courses: Strands Drill-and-practice (arithmetic fundamentals for fourth grade), Logic…

  2. The Aerosol Limb Imager: acousto-optic imaging of limb-scattered sunlight for stratospheric aerosol profiling

    NASA Astrophysics Data System (ADS)

    Elash, B. J.; Bourassa, A. E.; Loewen, P. R.; Lloyd, N. D.; Degenstein, D. A.

    2016-03-01

    The Aerosol Limb Imager (ALI) is an optical remote sensing instrument designed to image scattered sunlight from the atmospheric limb. These measurements are used to retrieve spatially resolved information of the stratospheric aerosol distribution, including spectral extinction coefficient and particle size. Here we present the design, development and test results of an ALI prototype instrument. The long-term goal of this work is the eventual realization of ALI on a satellite platform in low earth orbit, where it can provide high spatial resolution observations, both in the vertical and cross-track. The instrument design uses a large-aperture acousto-optic tunable filter (AOTF) to image the sunlit stratospheric limb in a selectable narrow wavelength band ranging from the visible to the near infrared. The ALI prototype was tested on a stratospheric balloon flight from the Canadian Space Agency (CSA) launch facility in Timmins, Canada, in September 2014. Preliminary analysis of the hyperspectral images indicates that the radiance measurements are of high quality, and we have used these to retrieve vertical profiles of stratospheric aerosol extinction coefficient from 650 to 1000 nm, along with one moment of the particle size distribution. Those preliminary results are promising and development of a satellite prototype of ALI within the Canadian Space Agency is ongoing.

  3. Fluorescence lifetime imaging of optically levitated aerosol: a technique to quantitatively map the viscosity of suspended aerosol particles.

    PubMed

    Fitzgerald, C; Hosny, N A; Tong, H; Seville, P C; Gallimore, P J; Davidson, N M; Athanasiadis, A; Botchway, S W; Ward, A D; Kalberer, M; Kuimova, M K; Pope, F D

    2016-08-21

    We describe a technique to measure the viscosity of stably levitated single micron-sized aerosol particles. Particle levitation allows the aerosol phase to be probed in the absence of potentially artefact-causing surfaces. To achieve this feat, we combined two laser based techniques: optical trapping for aerosol particle levitation, using a counter-propagating laser beam configuration, and fluorescent lifetime imaging microscopy (FLIM) of molecular rotors for the measurement of viscosity within the particle. Unlike other techniques used to measure aerosol particle viscosity, this allows for the non-destructive probing of viscosity of aerosol particles without interference from surfaces. The well-described viscosity of sucrose aerosol, under a range of relative humidity conditions, is used to validate the technique. Furthermore we investigate a pharmaceutically-relevant mixture of sodium chloride and salbutamol sulphate under humidities representative of in vivo drug inhalation. Finally, we provide a methodology for incorporating molecular rotors into already levitated particles, thereby making the FLIM/optical trapping technique applicable to real world aerosol systems, such as atmospheric aerosols and those generated by pharmaceutical inhalers. PMID:27430158

  4. The Screen Display Syntax for CAI.

    ERIC Educational Resources Information Center

    Richards, Boyd F.; Salisbury, David F.

    1987-01-01

    Describes four storyboard techniques frequently used in designing computer assisted instruction (CAI) programs, and explains screen display syntax (SDS), a new technique combining the major advantages of the storyboard techniques. SDS was developed to facilitate communication among designers, programmers, and editors working on a large CAI basic…

  5. Implications of Windowing Techniques for CAI.

    ERIC Educational Resources Information Center

    Heines, Jesse M.; Grinstein, Georges G.

    This paper discusses the use of a technique called windowing in computer assisted instruction to allow independent control of functional areas in complex CAI displays and simultaneous display of output from a running computer program and coordinated instructional material. Two obstacles to widespread use of CAI in computer science courses are…

  6. CAI: Its Cost and Its Role.

    ERIC Educational Resources Information Center

    Pressman, Israel; Rosenbloom, Bruce

    1984-01-01

    Describes and evaluates costs of hardware, software, training, and maintenance for computer assisted instruction (CAI) as they relate to total system cost. An example of an educational system provides an illustration of CAI cost analysis. Future developments, cost effectiveness, affordability, and applications in public and private environments…

  7. The Evolutionary Development of CAI Hardware.

    ERIC Educational Resources Information Center

    Stifle, John E.

    After six years of research in computer assisted instruction (CAI) using PLATO III, a decision was made at the University of Illinois to develop a larger system as a national CAI resource. This document describes the design specifications and problems in the development of PLATO IV, a system which is capable of accomodating up to 4,000 terminals…

  8. Economic Evaluation of CAI in Special Education.

    ERIC Educational Resources Information Center

    Wilkinson, Gene L.

    This is an introductory presentation of economic evaluation methods for assessing computer-assisted instruction (CAI). Six different costing techniques, including cost effectiveness, are reviewed. Cost effectiveness is then examined in terms of its usefulness for evaluating CAI. A simplified system for cost effectiveness evaluation is presented…

  9. Computers for Your Classroom: CAI and CMI.

    ERIC Educational Resources Information Center

    Thomas, David B.; Bozeman, William C.

    1981-01-01

    The availability of compact, low-cost computer systems provides a means of assisting classroom teachers in the performance of their duties. Computer-assisted instruction (CAI) and computer-managed instruction (CMI) are two applications of computer technology with which school administrators should become familiar. CAI is a teaching medium in which…

  10. A unified framework for producing CAI melting, Wark-Lovering rims and bowl-shaped CAIs

    NASA Astrophysics Data System (ADS)

    Liffman, Kurt; Cuello, Nicolas; Paterson, David A.

    2016-10-01

    Calcium-Aluminium inclusions (CAIs) formed in the Solar system, some 4567 million years ago. CAIs are almost always surrounded by Wark-Lovering rims (WLRs), which are a sequence of thin, mono/bi-mineralic layers of refractory minerals, with a total thickness in the range of 1-100 microns. Recently, some CAIs have been found that have tektite-like bowl-shapes. To form such shapes, the CAI must have travelled through a rarefied gas at hypersonic speeds. We show how CAIs may have been ejected from the inner solar accretion disc via the centrifugal interaction between the solar magnetosphere and the inner disc rim. They subsequently punched through the hot, inner disc rim wall at hypersonic speeds. This re-entry heating partially or completely evaporated the CAIs. Such evaporation could have significantly increased the metal abundances of the inner disc rim. High speed movement through the inner disc produced WLRs. To match the observed thickness of WLRs required metal abundances at the inner disc wall that are of order 10 times that of standard solar abundances. The CAIs cooled as they moved away from the protosun, the deduced CAI cooling rates are consistent with the CAI cooling rates obtained from experiment and observation. The speeds and gas densities required to form bowl-shaped CAIs are also consistent with the expected speeds and gas densities for larger, ˜1 cm, CAIs punching through an inner accretion disc wall.

  11. CAIS. Condition Assessment Information System

    SciTech Connect

    Oak, J.C.

    1996-09-30

    CAIS is used by Architects and Engineers to gather facility condition assessment data. This data consist of architectural, civil, structural, electrical, and mechanical systems and components that are a part of the inspected facility. Data is collected using a hand-held, pen-based computer system which is preprogrammed for detailed inventories of individual components. The program is deficiency based for collecting data for repair and replacement observations. Observations are recorded on checklists preformatted to individual site needs, allowing for comments on unusual conditions to be documented on site. Data is transferred to a central database, where it can be reviewed, costed, and reported on using different scenarios. Information can be transferred to the DOE operations offices as well as to the DOE FIMS database for each site.

  12. Multiangle Imaging Spectroradiometer (MISR) Global Aerosol Optical Depth Validation Based on 2 Years of Coincident Aerosol Robotic Network (AERONET) Observations

    NASA Technical Reports Server (NTRS)

    Kahn, Ralph A.; Gaitley, Barbara J.; Martonchik, John V.; Diner, David J.; Crean, Kathleen A.; Holben, Brent

    2005-01-01

    Performance of the Multiangle Imaging Spectroradiometer (MISR) early postlaunch aerosol optical thickness (AOT) retrieval algorithm is assessed quantitatively over land and ocean by comparison with a 2-year measurement record of globally distributed AERONET Sun photometers. There are sufficient coincident observations to stratify the data set by season and expected aerosol type. In addition to reporting uncertainty envelopes, we identify trends and outliers, and investigate their likely causes, with the aim of refining algorithm performance. Overall, about 2/3 of the MISR-retrieved AOT values fall within [0.05 or 20% x AOT] of Aerosol Robotic Network (AERONET). More than a third are within [0.03 or 10% x AOT]. Correlation coefficients are highest for maritime stations (approx.0.9), and lowest for dusty sites (more than approx.0.7). Retrieved spectral slopes closely match Sun photometer values for Biomass burning and continental aerosol types. Detailed comparisons suggest that adding to the algorithm climatology more absorbing spherical particles, more realistic dust analogs, and a richer selection of multimodal aerosol mixtures would reduce the remaining discrepancies for MISR retrievals over land; in addition, refining instrument low-light-level calibration could reduce or eliminate a small but systematic offset in maritime AOT values. On the basis of cases for which current particle models are representative, a second-generation MISR aerosol retrieval algorithm incorporating these improvements could provide AOT accuracy unprecedented for a spaceborne technique.

  13. The Sensitivity of Multiangle Imaging to Natural Mixes of Aerosols Over Ocean

    NASA Technical Reports Server (NTRS)

    Kahn, R.; Banerjee, P.; McDonald, D.

    1999-01-01

    Multiangle, multispectral remote sensing observations, such as those anticipated from the Earth Observing System (EOS) Multi-angle Imaging SpectroRadiomenter (MISR), can significantly improve our ability to constrain aerosol properties based on a generic retrieval approach; top-of-atmosphere radiances were interpreted in terms of a single, average aerosol population having unimodal size distribution and uniform composition.

  14. Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight (CXIDB ID 16)

    DOE Data Explorer

    Loh, N. Duane

    2012-06-20

    This deposition includes the aerosol diffraction images used for phasing, fractal morphology, and time-of-flight mass spectrometry. Files in this deposition are ordered in subdirectories that reflect the specifics.

  15. Evaluation of the Moderate Resolution Imaging Spectroradiometer aerosol products at two Aerosol Robotic Network stations in China

    NASA Astrophysics Data System (ADS)

    Mi, Wen; Li, Zhanqing; Xia, Xiangao; Holben, Brent; Levy, Robert; Zhao, Fengsheng; Chen, Hongbin; Cribb, Maureen

    2007-11-01

    Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol products have been used to address aerosol climatic issues in many parts of the world, but their quality has yet to be determined over China. This paper presents a thorough evaluation of aerosol optical depth (AOD) data retrieved from MODIS collections 4 (C004) and 5 (C005) at two AERONET sites in northern and southeastern China. Established under the aegis of the East Asian Study of Tropospheric Aerosols: An International Regional Experiment (EAST-AIRE) project, the two sites, Xianghe and Taihu, have distinct ecosystems and climate regimes, resulting in differences in retrieval performance. At the rural northeastern site (Xianghe), MODIS C004 retrievals generally overestimate AOD at 550 nm during clean days, with the largest errors occurring during winter. In the warm and humid regions of southeastern China (Taihu), MODIS C004 retrievals overestimate AOD throughout the year. The systematic error at Xianghe is primarily due to the fixed surface reflectance ratio, while as the error at Taihu is mainly caused by the choice of the single scattering albedo (SSA) for the fine model aerosols. Both problems are alleviated considerably in the C005. The comparisons between C005 retrievals and AERONET data show much higher correlation coefficient, lower offset and a slope closer to unity. Also, the variability of AOD retrieval among neighboring pixels is reduced by several factors. The strong overestimation problem at small AOD values was fixed by using dynamic reflectance ratios that vary with the vegetation index and scattering angle. However, significant uncertainties remain because of the use of highly simplified aerosol models.

  16. Aerosol Imaging with a Soft X-ray Free Electron Laser

    SciTech Connect

    Bogan, Michael J.; Boutet, Sebastien; Chapman, Henry N.; Marchesini, Stefano; Barty, Anton; Benner, W.Henry Rohner, Urs; Frank, Matthias; Hau-Riege, Stefan P.; Bajt, Sasa; Woods, Bruce; Seibert, M.M.; Iwan, Bianca; Timneanu, Nicusor; Hajdu, Janos; Schulz, Joachim; /DESY

    2011-08-22

    Lasers have long played a critical role in the advancement of aerosol science. A new regime of ultrafast laser technology has recently be realized, the world's first soft xray free electron laser. The Free electron LASer in Hamburg, FLASH, user facility produces a steady source of 10 femtosecond pulses of 7-32 nm x-rays with 10{sub 12} photons per pulse. The high brightness, short wavelength, and high repetition rate (>500 pulses per second) of this laser offers unique capabilities for aerosol characterization. Here we use FLASH to perform the highest resolution imaging of single PM2.5 aerosol particles in flight to date. We resolve to 35 nm the morphology of fibrous and aggregated spherical carbonaceous nanoparticles that existed for less than two milliseconds in vacuum. Our result opens the possibility for high spatialand time-resolved single particle aerosol dynamics studies, filling a critical technological need in aerosol science.

  17. Atmospheric aerosol and molecular backscatter imaging effects on direct detection LADAR

    NASA Astrophysics Data System (ADS)

    Youmans, Douglas G.

    2015-05-01

    Backscatter from atmospheric aerosols and molecular nitrogen and oxygen causes "clutter" noise in direct detection ladar applications operating within the atmosphere. The backscatter clutter is more pronounced in multiple pulse, high PRF ladars where pulse-averaging is used to increase operating range. As more and more pulses are added to the wavetrain the backscatter increases. We analyze the imaging of a transmitted Gaussian laser-mode multi-pulse wave-train scatteried off of aerosols and molecules at the focal plane including angular-slew rate resulting from optical tracking, angular lead-angle, and bistatic-optics spatial separation. The defocused backscatter images, from those pulses closest to the receiver, are analyzed using a simple geometrical optics approximation. Methods for estimating the aerosol number density versus altitude and the volume backscatter coefficient of the aerosols are also discussed.

  18. CAIs in Semarkona (LL3.0)

    NASA Technical Reports Server (NTRS)

    Mishra, R. K.; Simon, J. I.; Ross, D. K.; Marhas, K. K.

    2016-01-01

    Calcium, Aluminum-rich inclusions (CAIs) are the first forming solids of the Solar system. Their observed abundance, mean size, and mineralogy vary quite significantly between different groups of chondrites. These differences may reflect the dynamics and distinct cosmochemical conditions present in the region(s) of the protoplanetary disk from which each type likely accreted. Only about 11 such objects have been found in L and LL type while another 57 have been found in H type ordinary chondrites, compared to thousands in carbonaceous chondrites. At issue is whether the rare CAIs contained in ordinary chondrites truly reflect a distinct population from the inclusions commonly found in other chondrite types. Semarkona (LL3.00) (fall, 691 g) is the most pristine chondrite available in our meteorite collection. Here we report petrography and mineralogy of 3 CAIs from Semarkona

  19. Aerosol source plume physical characteristics from space-based multiangle imaging

    NASA Astrophysics Data System (ADS)

    Kahn, Ralph A.; Li, W.-H.; Moroney, Catherine; Diner, David J.; Martonchik, John V.; Fishbein, Evan

    2007-06-01

    Models that assess aerosol effects on regional air quality and global climate parameterize aerosol sources in terms of amount, type, and injection height. The multiangle imaging spectroradiometer (MISR) aboard NASA's Terra satellite retrieves total column aerosol optical thickness (AOT), and aerosol type over cloud-free land and water. A stereo-matching algorithm automatically retrieves reflecting-layer altitude wherever clouds or aerosol plumes have discernable spatial contrast, with about 500-m accuracy, at 1.1-km horizontal resolution. Near-source biomass burning smoke, volcanic effluent, and desert dust plumes are observed routinely, providing information about aerosol amount, particle type, and injection height useful for modeling applications. Compared to background aerosols, the plumes sampled have higher AOT, contain particles having expected differences in Angstrom exponent, size, single-scattering albedo, and for volcanic plume and dust cloud cases, particle shape. As basic thermodynamics predicts, thin aerosol plumes lifted only by regional winds or less intense heat sources are confined to the boundary layer. However, when sources have sufficient buoyancy, the representative plumes studied tend to concentrate within discrete, high-elevation layers of local stability; the aerosol is not uniformly distributed up to a peak altitude, as is sometimes assumed in modeling. MISR-derived plume heights, along with meteorological profile data from other sources, make it possible to relate radiant energy flux observed by the moderate resolution imaging spectroradiometer (MODIS), also aboard the Terra spacecraft, to convective heat flux that plays a major role in buoyant plume dynamics. A MISR climatology of plume behavior based on these results is being developed.

  20. Sensitivity of Multiangle Imaging to the Optical and Microphysical Properties of Biomass Burning Aerosols

    NASA Technical Reports Server (NTRS)

    Chen, Wei-Ting; Kahn, Ralph A.; Nelson, David; Yau, Kevin; Seinfeld, John H.

    2008-01-01

    The treatment of biomass burning (BB) carbonaceous particles in the Multiangle Imaging SpectroRadiometer (MISR) Standard Aerosol Retrieval Algorithm is assessed, and algorithm refinements are suggested, based on a theoretical sensitivity analysis and comparisons with near-coincident AERONET measurements at representative BB sites. Over the natural ranges of BB aerosol microphysical and optical properties observed in past field campaigns, patterns of retrieved Aerosol Optical Depth (AOD), particle size, and single scattering albedo (SSA) are evaluated. On the basis of the theoretical analysis, assuming total column AOD of 0.2, over a dark, uniform surface, MISR can distinguish two to three groups in each of size and SSA, except when the assumed atmospheric particles are significantly absorbing (mid-visible SSA approx.0.84), or of medium sizes (mean radius approx.0.13 pin); sensitivity to absorbing, medium-large size particles increases considerably when the assumed column AOD is raised to 0.5. MISR Research Aerosol Retrievals confirm the theoretical results, based on coincident AERONET inversions under BB-dominated conditions. When BB is externally mixed with dust in the atmosphere, dust optical model and surface reflection uncertainties, along with spatial variability, contribute to differences between the Research Retrievals and AERONET. These results suggest specific refinements to the MISR Standard Aerosol Algorithm complement of component particles and mixtures. They also highlight the importance for satellite aerosol retrievals of surface reflectance characterization, with accuracies that can be difficult to achieve with coupled surface-aerosol algorithms in some higher AOD situations.

  1. CAI in Music Theory: Paradigms: Potential: Problems.

    ERIC Educational Resources Information Center

    Hultberg, W. Earle; Hultberg, Mary Lou

    Computer-assisted instructional programs have been developed at the State University College at Potsdam, New York, to teach basic concepts of music theory. The Computer-based Learning Experiences in Music Fundamentals (CLEF) project has spawned computer assisted instruction (CAI) programs which use an IBM 360/30 configuration with 2741 terminals…

  2. Individual Differences in Learner Controlled CAI.

    ERIC Educational Resources Information Center

    Judd, Wilson A.; And Others

    Two assumptions in support of learner-controlled computer-assisted instruction (CAI) are that (1) instruction administered under learner control will be less aversive than if administered under program control, and (2) the student is sufficiently aware of his learning state to make, in most instances, his own instructional decisions. Some 130…

  3. The Evolutionary Development of CAI Evaluation Approaches.

    ERIC Educational Resources Information Center

    Avner, R. A.

    The role of evaluation in the development of evolutionary procedures is briefly described and highlighted. Four aspects of evaluation technique which distinguish efficient from inefficient CAI programs are identified. Evaluation of products is also characterized. Findings of a continuing survey of students via questionnaire as to the value of…

  4. The Relevance of AI Research to CAI.

    ERIC Educational Resources Information Center

    Kearsley, Greg P.

    This article provides a tutorial introduction to Artificial Intelligence (AI) research for those involved in Computer Assisted Instruction (CAI). The general theme is that much of the current work in AI, particularly in the areas of natural language understanding systems, rule induction, programming languages, and socratic systems, has important…

  5. Man-Computer Communications and CAI.

    ERIC Educational Resources Information Center

    Hunka, S.

    A variety of direct and indirect instructional activities during the last ten years have employed computers. Within Computer Assisted Instruction (CAI) programs, the following broad classes of instructional strategies have been generally accepted: tutorial, drill and practice, review, testing, remediation and diagnosis, problem solving, and…

  6. The Evolutionary Development of CAI Courseware.

    ERIC Educational Resources Information Center

    Steinberg, Esther R.

    The history of computer-assisted instruction (CAI) courseware is described with specific reference to the PLATO system. Among the goals of courseware authors are finding better ways to develop the cognitive skills of students, to shift some of the burden of routine classroom instruction away from the teacher so that more class time can be spent in…

  7. Chemometric analysis of multi-sensor hyperspectral images of coarse mode aerosol particles for the image-based investigation on aerosol particles

    NASA Astrophysics Data System (ADS)

    Ofner, Johannes; Kamilli, Katharina A.; Eitenberger, Elisabeth; Friedbacher, Gernot; Lendl, Bernhard; Held, Andreas; Lohninger, Hans

    2015-04-01

    Multi-sensor hyperspectral imaging is a novel technique, which allows the determination of composition, chemical structure and pure components of laterally resolved samples by chemometric analysis of different hyperspectral datasets. These hyperspectral datasets are obtained by different imaging methods, analysing the same sample spot and superimposing the hyperspectral data to create a single multi-sensor dataset. Within this study, scanning electron microscopy (SEM), Raman and energy-dispersive X-ray spectroscopy (EDX) images were obtained from size-segregated aerosol particles, sampled above Western Australian salt lakes. The particles were collected on aluminum foils inside a 2350 L Teflon chamber using a Sioutas impactor, sampling aerosol particles of sizes between 250 nm and 10 µm. The complex composition of the coarse-mode particles can be linked to primary emissions of inorganic species as well as to oxidized volatile organic carbon (VOC) emissions. The oxidation products of VOC emissions are supposed to form an ultra-fine nucleation mode, which was observed during several field campaigns between 2006 and 2013. The aluminum foils were analysed using chemical imaging and electron microscopy. A Horiba LabRam 800HR Raman microscope was used for vibrational mapping of an area of about 100 µm x 100 µm of the foils at a resolution of about 1 µm. The same area was analysed using a Quanta FEI 200 electron microscope (about 250 nm resolution). In addition to the high-resolution image, the elemental composition could be investigated using energy-dispersive X-ray spectroscopy. The obtained hyperspectral images were combined into a multi-sensor dataset using the software package Imagelab (Epina Software Labs, www.imagelab.at). After pre-processing of the images, the multi-sensor hyperspectral dataset was analysed using several chemometric methods such as principal component analysis (PCA), hierarchical cluster analysis (HCA) and other multivariate methods. Vertex

  8. Determining Aerosol Plume Height from Two GEO Imagers: Lessons from MISR and GOES

    NASA Technical Reports Server (NTRS)

    Wu, Dong L.

    2012-01-01

    Aerosol plume height is a key parameter to determine impacts of particulate matters generated from biomass burning, wind-blowing dust, and volcano eruption. Retrieving cloud top height from stereo imageries from two GOES (Geostationary Operational Environmental Satellites) have been demonstrated since 1970's and the principle should work for aerosol plumes if they are optically thick. The stereo technique has also been used by MISR (Multiangle Imaging SpectroRadiometer) since 2000 that has nine look angles along track to provide aerosol height measurements. Knowing the height of volcano aerosol layers is as important as tracking the ash plume flow for aviation safety. Lack of knowledge about ash plume height during the 2010 Eyja'rjallajokull eruption resulted in the largest air-traffic shutdown in Europe since World War II. We will discuss potential applications of Asian GEO satellites to make stereo measurements for dust and volcano plumes.

  9. Clinical ventilation imaging with In-113m aerosol: a comparison with Kr-81m

    SciTech Connect

    Fazio, F.; Wollmer, P.; Lavender, J.P.; Barr, M.M.

    1982-04-01

    Following routine ventilation (Kr-81m)/perfusion (Tc-99m) scanning, we obtained aerosol ventilation scans using a solution of In-113m albumin and a settling-bag system. The large-volume settling bag reduces deposition of particles in the large airway by removing large droplets. The patient inhales the aerosol with 5-10 min of tidal breathing, then lung scans are obtained on a gamma camera. The energy of In-113m allows the ventilation scanning to be performed after Tc-99m perfusion scanning. Semiquantitative scoring of regional ventilation showed a close correlation (r = 0.97) between Kr-81m and In-113m aerosol ventilation scans. The aerosol technique gave a slight underestimation of ventilation compared with Kr-81m. This is explained by a slightly reduced penetration of particles to the periphery of the lung in patients with severe obstructive airways disease. In all cases, however, the aerosol did visualize all ventilated regions. The results indicate that this readily available aerosol technique can be useful for clinical ventilation imaging in multiple views.

  10. Production of aerosols by optical catapulting: Imaging, performance parameters and laser-induced plasma sampling rate

    NASA Astrophysics Data System (ADS)

    Abdelhamid, M.; Fortes, F. J.; Fernández-Bravo, A.; Harith, M. A.; Laserna, J. J.

    2013-11-01

    Optical catapulting (OC) is a sampling and manipulation method that has been extensively studied in applications ranging from single cells in heterogeneous tissue samples to analysis of explosive residues in human fingerprints. Specifically, analysis of the catapulted material by means of laser-induced breakdown spectroscopy (LIBS) offers a promising approach for the inspection of solid particulate matter. In this work, we focus our attention in the experimental parameters to be optimized for a proper aerosol generation while increasing the particle density in the focal region sampled by LIBS. For this purpose we use shadowgraphy visualization as a diagnostic tool. Shadowgraphic images were acquired for studying the evolution and dynamics of solid aerosols produced by OC. Aluminum silicate particles (0.2-8 μm) were ejected from the substrate using a Q-switched Nd:YAG laser at 1064 nm, while time-resolved images recorded the propagation of the generated aerosol. For LIBS analysis and shadowgraphy visualization, a Q-switched Nd:YAG laser at 1064 nm and 532 nm was employed, respectively. Several parameters such as the time delay between pulses and the effect of laser fluence on the aerosol production have been also investigated. After optimization, the particle density in the sampling focal volume increases while improving the aerosol sampling rate till ca. 90%.

  11. Aerosols

    Atmospheric Science Data Center

    2013-04-17

    ... air pollution is a complex mixture of particles of varying origins and compositions. Determining the type and abundance of tiny airborne ... Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees ...

  12. NALDA (Naval Aviation Logistics Data Analysis) CAI (computer aided instruction)

    SciTech Connect

    Handler, B.H. ); France, P.A.; Frey, S.C.; Gaubas, N.F.; Hyland, K.J.; Lindsey, A.M.; Manley, D.O. ); Hunnum, W.H. ); Smith, D.L. )

    1990-07-01

    Data Systems Engineering Organization (DSEO) personnel developed a prototype computer aided instruction CAI system for the Naval Aviation Logistics Data Analysis (NALDA) system. The objective of this project was to provide a CAI prototype that could be used as an enhancement to existing NALDA training. The CAI prototype project was performed in phases. The task undertaken in Phase I was to analyze the problem and the alternative solutions and to develop a set of recommendations on how best to proceed. The findings from Phase I are documented in Recommended CAI Approach for the NALDA System (Duncan et al., 1987). In Phase II, a structured design and specifications were developed, and a prototype CAI system was created. A report, NALDA CAI Prototype: Phase II Final Report, was written to record the findings and results of Phase II. NALDA CAI: Recommendations for an Advanced Instructional Model, is comprised of related papers encompassing research on computer aided instruction CAI, newly developing training technologies, instructional systems development, and an Advanced Instructional Model. These topics were selected because of their relevancy to the CAI needs of NALDA. These papers provide general background information on various aspects of CAI and give a broad overview of new technologies and their impact on the future design and development of training programs. The paper within have been index separately elsewhere.

  13. Influence of aerosol estimation on coastal water products retrieved from HICO images

    NASA Astrophysics Data System (ADS)

    Patterson, Karen W.; Lamela, Gia

    2011-06-01

    The Hyperspectral Imager for the Coastal Ocean (HICO) is a hyperspectral sensor which was launched to the International Space Station in September 2009. The Naval Research Laboratory (NRL) has been developing the Coastal Water Signatures Toolkit (CWST) to estimate water depth, bottom type and water column constituents such as chlorophyll, suspended sediments and chromophoric dissolved organic matter from hyperspectral imagery. The CWST uses a look-up table approach, comparing remote sensing reflectance spectra observed in an image to a database of modeled spectra for pre-determined water column constituents, depth and bottom type. In order to successfully use this approach, the remote sensing reflectances must be accurate which implies accurately correcting for the atmospheric contribution to the HICO top of the atmosphere radiances. One tool the NRL is using to atmospherically correct HICO imagery is Correction of Coastal Ocean Atmospheres (COCOA), which is based on Tafkaa 6S. One of the user input parameters to COCOA is aerosol optical depth or aerosol visibility, which can vary rapidly over short distances in coastal waters. Changes to the aerosol thickness results in changes to the magnitude of the remote sensing reflectances. As such, the CWST retrievals for water constituents, depth and bottom type can be expected to vary in like fashion. This work is an illustration of the variability in CWST retrievals due to inaccurate aerosol thickness estimation during atmospheric correction of HICO images.

  14. Polarized Imaging Nephelometer for Field and Aircraft Measurements of Aerosol Phase Function

    NASA Astrophysics Data System (ADS)

    Dolgos, G.; Martins, J.

    2012-12-01

    Aerosols have a significant impact on the radiative balance and water cycle of our planet through influencing atmospheric radiation. Remote sensing of aerosols relies on scattering phase matrix information to retrieve aerosol properties with frequent global coverage. At the Laboratory for Aerosols, Clouds and Optics (LACO) at the University of Maryland, Baltimore County we developed a new technique to directly measure the aerosol phase function and the degree of linear polarization of the scattered light (two elements of the phase matrix). We designed and built a portable instrument called the Polarized Imaging Nephelometer (PI-Neph). The PI-Neph successfully participated in dozens of flights of the NASA Development and Evaluation of satellite ValidatiOn Tools by Experimenters (DEVOTE) project and the Deep Convective Clouds and Chemistry (DC3) project. The ambient aerosol enters the PI-Neph through an inlet and the sample is illuminated by laser light (wavelength of 532 nm); the scattered light is imaged by a stationary wide field of view camera in the scattering angle range of 2° to 178°. (In some cases stray light limited the scattering angle range to 3° to 176°). The PI-Neph measurement of phase function and the AERONET (AErosol RObotic NETwork) retrievals have already been compared in some cases when the aircraft spiraled over AERONET sites, for example at NASA's Wallops Flight Facility, on October 18 2011, as shown in Figure 1. The differences between the PI-Neph and the AERONET retrievals can be attributed to differences between the ambient size distribution and the one sampled inside the aircraft. The data that is resolved with respect to scattering angle is used to compute the volume scattering coefficient. The above mentioned October 18 flight data showed good agreement between the PI-Neph measurements of volume scattering coefficient and the parallel TSI integrating nephelometer measurements. On average the TSI measurements were 1.02 times the PI

  15. Research on TRIZ and CAIs Application Problems for Technology Innovation

    NASA Astrophysics Data System (ADS)

    Li, Xiangdong; Li, Qinghai; Bai, Zhonghang; Geng, Lixiao

    In order to realize application of invent problem solve theory (TRIZ) and computer aided innovation software (CAIs) , need to solve some key problems, such as the mode choice of technology innovation, establishment of technology innovation organization network(TION), and achievement of innovative process based on TRIZ and CAIs, etc.. This paper shows that the demands for TRIZ and CAIs according to the characteristics and existing problem of the manufacturing enterprises. Have explained that the manufacturing enterprises need to set up an open TION of enterprise leading type, and achieve the longitudinal cooperation innovation with institution of higher learning. The process of technology innovation based on TRIZ and CAIs has been set up from researching and developing point of view. Application of TRIZ and CAIs in FY Company has been summarized. The application effect of TRIZ and CAIs has been explained using technology innovation of the close goggle valve product.

  16. Evaluation of Aerosol Properties over Ocean from Moderate Resolution Imaging Spectroradiometer (MODIS) during ACE-Asia

    NASA Technical Reports Server (NTRS)

    Chu, D. A.; Remer, L. A.; Kaufman, Y. J.; Schmid, B.; Redemann, J.; Knobelspiesse, K.; Chern, J.-D.; Livingston, J.; Russell, P. B.; Xiong, X.; Ridgway, W.

    2005-01-01

    The Aerosol Characterization Experiment-Asia (ACE-Asia) was conducted in March-May 2001 in the western North Pacific in order to characterize the complex mix of dust, smoke, urban/industrial pollution, and background marine aerosol that is observed in that region in springtime. The Moderate Resolution Imaging Spectroradiometer (MODIS) provides a large-scale regional view of the aerosol during the ACE-Asia time period. Focusing only on aerosol retrievals over ocean, MODIS data show latitudinal and longitudinal variation in the aerosol characteristics. Typically, aerosol optical depth (tau(sub a)) values at 0.55 micrometers are highest in the 30 deg. - 50 deg. latitude band associated with dust outbreaks. Monthly mean tau(sub a) in this band ranges approx. 0.40-70, although large differences between monthly mean and median values indicate the periodic nature of these dust outbreaks. The size parameters, fine mode fraction (eta), and effective radius (r(sub eff)) vary between monthly mean values of eta = 0.47 and r(sub eff)= 0.75 micrometers in the cleanest regions far offshore to approximately eta = 0.85 and r(sub eff) =.30 micrometers in near-shore regions dominated by biomass burning smoke. The collocated MODIS retrievals with airborne, ship-based, and ground-based radiometers measurements suggest that MODIS retrievals of spectral optical depth fall well within expected error (DELTA tau(sub a) = plus or minus 0.03 plus or minus 0.05 tau(sub a)) except in situations dominated by dust, in which cases MODIS overestimate both the aerosol loading and the aerosol spectral dependence. Such behavior is consistent with issues related to particle nonsphericity. Comparisons of MODIS-derived r(sub eff) with AERONET retrievals at the few occurrences of collocations show MODIS systematically underestimates particle size by 0.2 micrometers. Multiple-year analysis of MODIS aerosol size parameters suggests systematic differences between the year 2001 and the years 2000 and 2002

  17. Polarized Imaging Nephelometer for in situ airborne measurements of aerosol light scattering.

    PubMed

    Dolgos, Gergely; Martins, J Vanderlei

    2014-09-01

    Global satellite remote sensing of aerosols requires in situ measurements to enable the calibration and validation of algorithms. In order to improve our understanding of light scattering by aerosol particles, and to enable routine in situ airborne measurements of aerosol light scattering, we have developed an instrument, called the Polarized Imaging Nephelometer (PI-Neph). We designed and built the PI-Neph at the Laboratory for Aerosols, Clouds and Optics (LACO) of the University of Maryland, Baltimore County (UMBC). This portable instrument directly measures the ambient scattering coefficient and phase matrix elements of aerosols, in the field or onboard an aircraft. The measured phase matrix elements are the P(11), phase function, and P(12). Lasers illuminate the sampled ambient air and aerosol, and a wide field of view camera detects scattered light in a scattering angle range of 3° to 176°. The PI-Neph measures an ensemble of particles, supplying the relevant quantity for satellite remote sensing, as opposed to particle-by-particle measurements that have other applications. Comparisons with remote sensing measurements will have to consider aircraft inlet effects. The PI-Neph first measured at a laser wavelength of 532nm, and was first deployed successfully in 2011 aboard the B200 aircraft of NASA Langley during the Development and Evaluation of satellite ValidatiOn Tools by Experimenters (DEVOTE) project. In 2013, we upgraded the PI-Neph to measure at 473nm, 532nm, and 671nm nearly simultaneously. LACO has deployed the PI-Neph on a number of airborne field campaigns aboard three different NASA aircraft. This paper describes the PI-Neph measurement approach and validation by comparing measurements of artificial spherical aerosols with Mie theory. We provide estimates of calibration uncertainties, which show agreement with the small residuals between measurements of P(11) and -P(12)/P(11) and Mie theory. We demonstrate the capability of the PI-Neph to measure

  18. Polarized Imaging Nephelometer for in situ airborne measurements of aerosol light scattering.

    PubMed

    Dolgos, Gergely; Martins, J Vanderlei

    2014-09-01

    Global satellite remote sensing of aerosols requires in situ measurements to enable the calibration and validation of algorithms. In order to improve our understanding of light scattering by aerosol particles, and to enable routine in situ airborne measurements of aerosol light scattering, we have developed an instrument, called the Polarized Imaging Nephelometer (PI-Neph). We designed and built the PI-Neph at the Laboratory for Aerosols, Clouds and Optics (LACO) of the University of Maryland, Baltimore County (UMBC). This portable instrument directly measures the ambient scattering coefficient and phase matrix elements of aerosols, in the field or onboard an aircraft. The measured phase matrix elements are the P(11), phase function, and P(12). Lasers illuminate the sampled ambient air and aerosol, and a wide field of view camera detects scattered light in a scattering angle range of 3° to 176°. The PI-Neph measures an ensemble of particles, supplying the relevant quantity for satellite remote sensing, as opposed to particle-by-particle measurements that have other applications. Comparisons with remote sensing measurements will have to consider aircraft inlet effects. The PI-Neph first measured at a laser wavelength of 532nm, and was first deployed successfully in 2011 aboard the B200 aircraft of NASA Langley during the Development and Evaluation of satellite ValidatiOn Tools by Experimenters (DEVOTE) project. In 2013, we upgraded the PI-Neph to measure at 473nm, 532nm, and 671nm nearly simultaneously. LACO has deployed the PI-Neph on a number of airborne field campaigns aboard three different NASA aircraft. This paper describes the PI-Neph measurement approach and validation by comparing measurements of artificial spherical aerosols with Mie theory. We provide estimates of calibration uncertainties, which show agreement with the small residuals between measurements of P(11) and -P(12)/P(11) and Mie theory. We demonstrate the capability of the PI-Neph to measure

  19. Aerosol mobility imaging for rapid size distribution measurements

    DOEpatents

    Wang, Jian; Hering, Susanne Vera; Spielman, Steven Russel; Kuang, Chongai

    2016-07-19

    A parallel plate dimensional electrical mobility separator and laminar flow water condensation provide rapid, mobility-based particle sizing at concentrations typical of the remote atmosphere. Particles are separated spatially within the electrical mobility separator, enlarged through water condensation, and imaged onto a CCD array. The mobility separation distributes particles in accordance with their size. The condensation enlarges size-separated particles by water condensation while they are still within the gap of the mobility drift tube. Once enlarged the particles are illuminated by a laser. At a pre-selected frequency, typically 10 Hz, the position of all of the individual particles illuminated by the laser are captured by CCD camera. This instantly records the particle number concentration at each position. Because the position is directly related to the particle size (or mobility), the particle size spectra is derived from the images recorded by the CCD.

  20. Effect of the aerosol type uncertainty on the surface reflectance retrieval using CHRIS/PROBA hyperspectral images over land.

    NASA Astrophysics Data System (ADS)

    Tirelli, C.; Manzo, C.; Curci, G.; Bassani, C.

    2014-12-01

    The surface reflectance is crucial for the quantitative analysis of land surface properties in geological, agricultural and urban studies. The first requirement for a reliable surface reflectance estimation is an accurate atmospheric correction obtained by an appropriate selection of aerosol loading and type. The aerosol optical thickness at 550nm is widely used to describe the aerosol loading. Recent works have highlighted the relevant role of the aerosol types on the atmospheric correction process defined by their micro-physical properties. The aim of this work is to evaluate the radiative impact of the aerosol type on the surface reflectance obtained from CHRIS (Compact High Resolution Imaging Spectrometer) hyperspectral data over land. CHRIS on PROBA satellite is an high resolution multi-angular imaging spectrometer, operating in the visible near-infrared spectral domain (400 to 1000 nm). As test case the urban site of Brussels has been selected. The physically-based algorithm CHRIS@CRI (CHRIS Atmospherically Corrected Reflectance Imagery) has been developed specifically for CHRIS data by using the vector version of 6S (6SV) radiative transfer model. The atmospheric data needed for the atmospheric correction were obtained from CIMEL CE-318 of the Brussels AERONET station. CHRIS images were selected if simultaneous AERONET data were available. Other specific requirements for imagery acquisition were high aerosol loading and high solar irradiation. The aerosol radiative impact has been investigated comparing the reflectance obtained by applying the CHRIS@CRI algorithm with different aerosol types: the three aerosol standard of 6SV and two characterized by specific microphysical properties provided by the AERONET station and calculated with FlexAOD code (a post-processing tool of the chemical transport model GEOS-Chem), respectively. The results show a clear dependence of the atmospheric correction results on the aerosol absorption properties.

  1. Computer System Requirements for CAI/CMI Research.

    ERIC Educational Resources Information Center

    Fitzhugh, Robert J.

    This paper oriented for new researchers entering the field of CAI research discusses the research experience in this area, outlines some of the important computer requirements of CAI research, and proposes a conservative computer development strategy to meet those requirements. The development of PLATO and TICCIT are described as examples of the…

  2. An Intelligent CAI Monitor and Generative Tutor. Final Report.

    ERIC Educational Resources Information Center

    Koffman, Elliot B.; Perry, James

    This final report summarizes research findings and presents a model for generative computer assisted instruction (CAI) with respect to its usefulness in the classroom environment. Methods used to individualize instruction, and the evolution of a procedure used to select a concept for presentation to a student with the generative CAI system are…

  3. A CAI Study of Learning Geologic Time and Evolution.

    ERIC Educational Resources Information Center

    Young, James P.; Stolurow, Lawrence M.

    Twenty-two college students in science education were given an adjunctive computer-assisted instruction (CAI) program by means of typewriter consoles and computer-controlled colored slide presentations of critical information. Students were pretested, told how to respond at the student console, taught by the Harvard CAI System, and posttested. The…

  4. A Pilot CAI Scheme for the Malaysian Secondary Education System.

    ERIC Educational Resources Information Center

    Rao, A. Kanakaratnam; Rao, G. S.

    1982-01-01

    A multi-phase computer aided instruction (CAI) scheme for Malaysian Secondary Schools and Matriculation Centres attached to local universities is presented as an aid for improving instruction and for solving some problems presently faced by the Malaysian Secondary Education System. Some approaches for successful implementation of a CAI scheme are…

  5. Fifteen Years of Teaching Elementary Applied Statistics Using CAI.

    ERIC Educational Resources Information Center

    Hunka, S.

    A computer-assisted instructional (CAI) course in applied statistics has been taught for 15 years in the Faculty of Education at the University of Manitoba. The CAI courseware was originally created to be the primary mode of instruction for the course, and it is very extensive in terms of content and style of presentation. The course includes 14…

  6. A CAI Approach to Teaching an Office Technology Course.

    ERIC Educational Resources Information Center

    D'Souza, Patricia Veasey

    1989-01-01

    Describes study that investigated the difference between computer-assisted instruction (CAI) and traditional lecture instruction in teaching an office technology course. The effects of CAI on student achievement and student attitudes is discussed, hypotheses tested and pretests and posttests are described, and further research needs are suggested.…

  7. The Effectiveness of CAI Designed for the Hearing-Impaired.

    ERIC Educational Resources Information Center

    Fogel, Nancy S.

    Two pilot studies probed effectiveness of linguistically controlled, highly visual computer-assisted instruction (CAI) for English grammar instruction with hearing-impaired high school students (N=29 in the first study and N=71 in the second). Results from the first study suggested that state-of-the-art CAI designed specifically for use with this…

  8. Comparison between radioactive aerosol, technegas and krypton for ventilation imaging in healthy calves.

    PubMed

    Coghe, J; Votion, D; Lekeux, P

    2000-07-01

    The use of lung scintigraphy in calves necessitates the validation of a ventilation (V) imaging agent compatible with clinical applications. This study aimed at defining the value of an inhaled radioactive aerosol (99mTc-DTPA) and a 'pseudogas' (Technegas) in the assessment of regional V in healthy conscious calves by comparing 99mTc-DTPA and Technegas deposition (D) images to V(V) images obtained from the steady-state inhalation of the short half-life krypton 81 (81mKr) gas. Images were compared by analysis of radioactivity distribution in computer-generated regions of interest within the right lung and D to V ratio images were generated in order to highlight areas of mismatching between 99mTc-DTPA or Technegas and 81mKr distributions. Results of this analysis showed that the 99mTc-DTPA aerosol droplets were unable to reach the lung parenchyma because of significant particle impaction in the major conducting airways. Better definition of the ventilated lung was obtained when using Technegas because of minimal deposition in conducting airways. Furthermore, the Technegas and 81mKr distribution patterns were highly equivalent.

  9. Aerosol Airmass Type Mapping Over the Urban Mexico City Region From Space-based Multi-angle Imaging

    NASA Technical Reports Server (NTRS)

    Patadia, F.; Kahn, R. A.; Limbacher, J. A.; Burton, S. P.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. W.

    2013-01-01

    Using Multi-angle Imaging SpectroRadiometer (MISR) and sub-orbital measurements from the 2006 INTEX-B/MILAGRO field campaign, in this study we explore MISR's ability to map different aerosol air mass types over the Mexico City metropolitan area. The aerosol air mass distinctions are based on shape, size and single scattering albedo retrievals from the MISR Research Aerosol Retrieval algorithm. In this region, the research algorithm identifies dust-dominated aerosol mixtures based on non-spherical particle shape, whereas spherical biomass burning and urban pollution particles are distinguished by particle size. Two distinct aerosol air mass types based on retrieved particle microphysical properties, and four spatially distributed aerosol air masses, are identified in the MISR data on 6 March 2006. The aerosol air mass type identification results are supported by coincident, airborne high-spectral-resolution lidar (HSRL) measurements. Aerosol optical depth (AOD) gradients are also consistent between the MISR and sub-orbital measurements, but particles having single-scattering albedo of approx. 0.7 at 558 nm must be included in the retrieval algorithm to produce good absolute AOD comparisons over pollution-dominated aerosol air masses. The MISR standard V22 AOD product, at 17.6 km resolution, captures the observed AOD gradients qualitatively, but retrievals at this coarse spatial scale and with limited spherical absorbing particle options underestimate AOD and do not retrieve particle properties adequately over this complex urban region. However, we demonstrate how AOD and aerosol type mapping can be accomplished with MISR data over complex urban regions, provided the retrieval is performed at sufficiently high spatial resolution, and with a rich enough set of aerosol components and mixtures.

  10. Aerosol airmass type mapping over the Urban Mexico City region from space-based multi-angle imaging

    NASA Astrophysics Data System (ADS)

    Patadia, F.; Kahn, R. A.; Limbacher, J. A.; Burton, S. P.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. W.

    2013-09-01

    Using Multi-angle Imaging SpectroRadiometer (MISR) and sub-orbital measurements from the 2006 INTEX-B/MILAGRO field campaign, in this study we explore MISR's ability to map different aerosol air mass types over the Mexico City metropolitan area. The aerosol air mass distinctions are based on shape, size and single scattering albedo retrievals from the MISR Research Aerosol Retrieval algorithm. In this region, the research algorithm identifies dust-dominated aerosol mixtures based on non-spherical particle shape, whereas spherical biomass burning and urban pollution particles are distinguished by particle size. Two distinct aerosol air mass types based on retrieved particle microphysical properties, and four spatially distributed aerosol air masses, are identified in the MISR data on 6 March 2006. The aerosol air mass type identification results are supported by coincident, airborne high-spectral-resolution lidar (HSRL) measurements. Aerosol optical depth (AOD) gradients are also consistent between the MISR and sub-orbital measurements, but particles having single-scattering albedo of ≈0.7 at 558 nm must be included in the retrieval algorithm to produce good absolute AOD comparisons over pollution-dominated aerosol air masses. The MISR standard V22 AOD product, at 17.6 km resolution, captures the observed AOD gradients qualitatively, but retrievals at this coarse spatial scale and with limited spherical absorbing particle options underestimate AOD and do not retrieve particle properties adequately over this complex urban region. However, we demonstrate how AOD and aerosol type mapping can be accomplished with MISR data over complex urban regions, provided the retrieval is performed at sufficiently high spatial resolution, and with a rich enough set of aerosol components and mixtures.

  11. Variability of Marine Aerosol Fine-Mode Fraction and Estimates of Anthropogenic Aerosol Component Over Cloud-Free Oceans from the Moderate Resolution Imaging Spectroradiometer (MODIS)

    NASA Technical Reports Server (NTRS)

    Yu, Hongbin; Chin, Mian; Remer, Lorraine A.; Kleidman, Richard G.; Bellouin, Nicolas; Bian, Huisheng; Diehl, Thomas

    2009-01-01

    In this study, we examine seasonal and geographical variability of marine aerosol fine-mode fraction (f(sub m)) and its impacts on deriving the anthropogenic component of aerosol optical depth (tau(sub a)) and direct radiative forcing from multispectral satellite measurements. A proxy of f(sub m), empirically derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 5 data, shows large seasonal and geographical variations that are consistent with the Goddard Chemistry Aerosol Radiation Transport (GOCART) and Global Modeling Initiative (GMI) model simulations. The so-derived seasonally and spatially varying f(sub m) is then implemented into a method of estimating tau(sub a) and direct radiative forcing from the MODIS measurements. It is found that the use of a constant value for fm as in previous studies would have overestimated Ta by about 20% over global ocean, with the overestimation up to 45% in some regions and seasons. The 7-year (2001-2007) global ocean average tau(sub a) is 0.035, with yearly average ranging from 0.031 to 0.039. Future improvement in measurements is needed to better separate anthropogenic aerosol from natural ones and to narrow down the wide range of aerosol direct radiative forcing.

  12. Reflections on current and future applications of multiangle imaging to aerosol and cloud remote sensing

    NASA Astrophysics Data System (ADS)

    Diner, David

    2010-05-01

    The Multi-angle Imaging SpectroRadiometer (MISR) instrument has been collecting global Earth data from NASA's Terra satellite since February 2000. With its 9 along-track view angles, 4 spectral bands, intrinsic spatial resolution of 275 m, and stable radiometric and geometric calibration, no instrument that combines MISR's attributes has previously flown in space, nor is there is a similar capability currently available on any other satellite platform. Multiangle imaging offers several tools for remote sensing of aerosol and cloud properties, including bidirectional reflectance and scattering measurements, stereoscopic pattern matching, time lapse sequencing, and potentially, optical tomography. Current data products from MISR employ several of these techniques. Observations of the intensity of scattered light as a function of view angle and wavelength provide accurate measures of aerosol optical depths (AOD) over land, including bright desert and urban source regions. Partitioning of AOD according to retrieved particle classification and incorporation of height information improves the relationship between AOD and surface PM2.5 (fine particulate matter, a regulated air pollutant), constituting an important step toward a satellite-based particulate pollution monitoring system. Stereoscopic cloud-top heights provide a unique metric for detecting interannual variability of clouds and exceptionally high quality and sensitivity for detection and height retrieval for low-level clouds. Using the several-minute time interval between camera views, MISR has enabled a pole-to-pole, height-resolved atmospheric wind measurement system. Stereo imagery also makes possible global measurement of the injection heights and advection speeds of smoke plumes, volcanic plumes, and dust clouds, for which a large database is now available. To build upon what has been learned during the first decade of MISR observations, we are evaluating algorithm updates that not only refine retrieval

  13. FIB-NanoSIMS-TEM Coordinated Study of a Wark-Lovering Rim in a Vigarano Type A CAI

    NASA Technical Reports Server (NTRS)

    Cai, A.; Ito, M.; Keller, L. P.; Ross, D. K.; Nakamura-Messenger, K.

    2010-01-01

    Wark-Lovering (WL) rims are thin multi layered mineral sequences that surround most Ca, Al-rich inclusions (CAIs). Unaltered WL rims are composed of the same primary high temperature minerals as CAIs, such as melilite, spinel, pyroxene, hibonite, perovskite, anorthite and olivine. It is still unclear whether the rim minerals represent a different generation formed by a separate event from their associated CAIs or are a byproduct of CAI formation. Several models have been proposed for the origins of WL rims including condensation, flashheating, reaction of a CAI with a Mg-Si-rich reservoir (nebular gas or solid); on the basis of mineralogy, abundances of trace elements, O and Mg isotopic studies. Detailed mineralogical characterizations of WL rims at micrometer to nanometer scales have been obtained by TEM observations, but so far no coordinated isotopic - mineralogical studies have been performed. Thus, we have applied an O isotopic imaging technique by NanoSIMS 50L to investigate heterogeneous distributions of O isotopic ratios in minerals within a cross section of a WL rim prepared using a focused ion beam (FIB) instrument. After the isotopic measurements, we determine the detailed mineralogy and microstructure of the same WL FIB section to gain insight into its petrogenesis. Here we present preliminary results from O isotopic and elemental maps by NanoSIMS and mineralogical analysis by FE-SEM of a FIB section of a WL rim in the Vigarano reduced CV3 chondrite.

  14. New Titanium Isotope Data for Allende and Efremovka CAIs

    NASA Astrophysics Data System (ADS)

    Leya, Ingo; Schönbächler, Maria; Krähenbühl, Urs; Halliday, Alex N.

    2009-09-01

    We measured the titanium (Ti) isotope composition, i.e., 50Ti/47Ti, 48Ti/47Ti, and 46Ti/47Ti, in five calcium-rich-aluminum-rich refractory inclusions (CAIs) from the oxidized CV3 chondrite Allende and in two CAIs from the reduced CV3 chondrite Efremovka. Our data indicate that CAIs are enriched in 50Ti/47Ti and 46Ti/47Ti and are slightly depleted in 48Ti/47Ti compared to normal Ti defined by ordinary chondrites, eucrites, ureilites, mesosiderites, Earth, Moon, and Mars. Some CAIs have an additional 50Ti excess of ~8ɛ relative to bulk carbonaceous chondrites, which are enriched in 50Ti by ~2ɛ relative to terrestrial values, leading to a total excess of ~10ɛ. This additional 50Ti excess is correlated with nucleosynthetic anomalies found in 62Ni and 96Zr, all indicating an origin from a neutron-rich stellar source. Bulk carbonaceous chondrites show a similar trend, however, the extent of the anomalies is either less than or similar to the smallest anomalies seen in CAIs. Mass balance calculations suggest that bulk Allende Ti possibly consists of a mixture of at least two Ti components, anomalous Ti located in CAIs and a normal component possibly for matrix and chondrules. This argues for a heterogeneous distribution of Ti isotopes in the solar system. The finding that anomalous Ti is concentrated in CAIs suggests that CAIs formed in a specific region of the solar system and were, after their formation, not homogeneously redistributed within the solar system. Combining the CAI data with improved model predictions for early solar system irradiation effects indicates that a local production scenario for the relatively short lived radionuclides can be excluded, because the production of, e.g., 10Be, 26Al, and 41Ca, would result in a significant collateral shift in Ti isotopes, which is not seen in the measured data.

  15. 99mTc-DTPA aerosol for same-day post-perfusion ventilation imaging: results of a multicentre study.

    PubMed

    Köhn, H; Mostbeck, A; Bachmayr, S; Eber, O; Galvan, G; Holm, C; König, B; Lind, P; Markt, B; Ogris, E

    1993-01-01

    A multicentre study was performed in an attempt to evaluate a submicronic technetium-99m diethylene triamine penta-acetic acid aerosol generated by a newly developed delivery system, the aerosol production equipment (APE nebulizer), for same-day post-perfusion ventilation imaging in patients with clinically suspected pulmonary embolism. Quantitative comparison between the DTPA aerosol and krypton gas demonstrated a close correlation with respect to regional pulmonary distribution of activity and peripheral lung penetration (n = 14, r = 0.94, P < 0.001 and r = 0.75, P < 0.0025, respectively). In 169 consecutive patients, DTPA aerosol images performed immediately following perfusion (inhalation scan I) were compared to those carried out on the next day (inhalation scan II) with respect to image quality and assessment of perfusion-ventilation matches or mismatches. Agreement between inhalation scans I and II with respect to perfusion defects matched or mismatched to ventilation was found in 166/169 (98%) studies. The image quality of inhalation scan I was equal to that of scan II in 72%; inhalation scan I was superior in 11% of cases, while scan II was superior in 17%. This submicronic 99mTc-labelled DTPA aerosol is well suited for fast same-day post-perfusion ventilation imaging in patients with clinical suspicion of pulmonary embolism.

  16. CAI System of Obunsha Co., Ltd. Using CD-ROM

    NASA Astrophysics Data System (ADS)

    Todokoro, Shigeru; Mukai, Yoshihiro

    This paper introduces the present status of R & D on CAI teaching materials in Obunsha Co., Ltd. Characteristics of CAI using CD-ROM as well as Culture-in CAI Teaching Materials System for junior high school English are described. The system consists of CD-ROM driver XM-2000 and Pasopia 700 of Toshiba Corporation having both features of CD-ROM and FD. CD-ROM stores vast amount of voice data while FD does text and graphics data. It is a frame-oriented mode system enabling to raise learning effect.

  17. Liquid-liquid phase separation in aerosol particles: Imaging at the Nanometer Scale

    SciTech Connect

    O'Brien, Rachel; Wang, Bingbing; Kelly, Stephen T.; Lundt, Nils; You, Yuan; Bertram, Allan K.; Leone, Stephen R.; Laskin, Alexander; Gilles, Mary K.

    2015-04-21

    Atmospheric aerosols can undergo phase transitions including liquid-liquid phase separation (LLPS) while responding to changes in the ambient relative humidity (RH). Here, we report results of chemical imaging experiments using environmental scanning electron microscopy (ESEM) and scanning transmission x-ray microscopy (STXM) to investigate the LLPS of micron sized particles undergoing a full hydration-dehydration cycle. Internally mixed particles composed of ammonium sulfate (AS) and either: limonene secondary organic carbon (LSOC), a, 4-dihydroxy-3-methoxybenzeneaceticacid (HMMA), or polyethylene glycol (PEG-400) were studied. Events of LLPS with apparent core-shell particle morphology were observed for all samples with both techniques. Chemical imaging with STXM showed that both LSOC/AS and HMMA/AS particles were never homogeneously mixed for all measured RH’s above the deliquescence point and that the majority of the organic component was located in the shell. The shell composition was estimated as 65:35 organic: inorganic in LSOC/AS and as 50:50 organic: inorganic for HMMA/AS. PEG-400/AS particles showed fully homogeneous mixtures at high RH and phase separated below 89-92% RH with an estimated 50:50% organic to inorganic mix in the shell. These two chemical imaging techniques are well suited for in-situ analysis of the hygroscopic behavior, phase separation, and surface composition of collected ambient aerosol particles.

  18. Liquid-liquid phase separation in aerosol particles: imaging at the nanometer scale.

    PubMed

    O'Brien, Rachel E; Wang, Bingbing; Kelly, Stephen T; Lundt, Nils; You, Yuan; Bertram, Allan K; Leone, Stephen R; Laskin, Alexander; Gilles, Mary K

    2015-04-21

    Atmospheric aerosols can undergo phase transitions including liquid-liquid phase separation (LLPS) while responding to changes in the ambient relative humidity (RH). Here, we report results of chemical imaging experiments using environmental scanning electron microscopy (ESEM) and scanning transmission X-ray microscopy (STXM) to investigate the LLPS of micrometer-sized particles undergoing a full hydration-dehydration cycle. Internally mixed particles composed of ammonium sulfate (AS) and either: limonene secondary organic carbon (LSOC), α, 4-dihydroxy-3-methoxybenzeneaceticacid (HMMA), or polyethylene glycol (PEG-400) were studied. Events of LLPS were observed for all samples with both techniques. Chemical imaging with STXM showed that both LSOC/AS and HMMA/AS particles were never homogeneously mixed for all measured RH's above the deliquescence point and that the majority of the organic component was located in the outer phase. The outer phase composition was estimated as 65:35 organic: inorganic in LSOC/AS and as 50:50 organic: inorganic for HMMA/AS. PEG-400/AS particles showed fully homogeneous mixtures at high RH and phase separated below 89-92% RH with an estimated 70:30% organic to inorganic mix in the outer phase. These two chemical imaging techniques are well suited for in situ analysis of the hygroscopic behavior, phase separation, and surface composition of collected ambient aerosol particles.

  19. Aerosol Plume Detection Algorithm Based on Image Segmentation of Scanning Atmospheric Lidar Data

    DOE PAGES

    Weekley, R. Andrew; Goodrich, R. Kent; Cornman, Larry B.

    2016-04-06

    An image-processing algorithm has been developed to identify aerosol plumes in scanning lidar backscatter data. The images in this case consist of lidar data in a polar coordinate system. Each full lidar scan is taken as a fixed image in time, and sequences of such scans are considered functions of time. The data are analyzed in both the original backscatter polar coordinate system and a lagged coordinate system. The lagged coordinate system is a scatterplot of two datasets, such as subregions taken from the same lidar scan (spatial delay), or two sequential scans in time (time delay). The lagged coordinatemore » system processing allows for finding and classifying clusters of data. The classification step is important in determining which clusters are valid aerosol plumes and which are from artifacts such as noise, hard targets, or background fields. These cluster classification techniques have skill since both local and global properties are used. Furthermore, more information is available since both the original data and the lag data are used. Performance statistics are presented for a limited set of data processed by the algorithm, where results from the algorithm were compared to subjective truth data identified by a human.« less

  20. Astrophysics of CAI formation as revealed by silicon isotope LA-MC-ICPMS of an igneous CAI

    NASA Astrophysics Data System (ADS)

    Shahar, Anat; Young, Edward D.

    2007-05-01

    Silicon isotope ratios of a typical CAI from the Leoville carbonaceous chondrite, obtained in situ by laser ablation MC-ICPMS, together with existing 25Mg/ 24Mg data, reveal a detailed picture of the astrophysical setting of CAI melting and subsequent heating. Models for the chemical and isotopic effects of evaporation of the molten CAI are used to produce a univariant relationship between PH 2 and time during melting. The result shows that this CAI was molten for a cumulative time of no more than 70 days and probably less than 15 days depending on temperature. The object could have been molten for an integrated time of just a few hours if isotope ratio zoning was eliminated after melting by high subsolidus temperatures (e.g., > 1300 K) for ˜ 500 yr. In all cases subsolidus heating sufficient to produce diffusion-limited isotope fractionation at the margin of the solidified CAI is required. These stable isotope data point to a two-stage history for this igneous CAI involving melting for a cumulative timescale of hours to months followed by subsolidus heating for years to hundreds of years. The thermobarometric history deduced from combining Si and Mg isotope ratio data implicates thermal processing in the disk, perhaps by passage through shockwaves, following melting. This study underscores the direct link between the meaning of stable isotope ratio zoning, or lack thereof, and the inferred astrophysical setting of melting and subsequent processing of CAIs.

  1. 3D Aerosol-Cloud Radiative Interaction Observed in Collocated MODIS and ASTER Images of Cumulus Cloud Fields

    NASA Technical Reports Server (NTRS)

    Wen, Guoyong; Marshak, Alexander; Cahalan, Robert F.; Remer, Lorraine A.; Kleidman, Richard G.

    2007-01-01

    3D aerosol-cloud interaction is examined by analyzing two images containing cumulus clouds in biomass burning regions in Brazil. The research consists of two parts. The first part focuses on identifying 3D clo ud impacts on the reflectance of pixel selected for the MODIS aerosol retrieval based purely on observations. The second part of the resea rch combines the observations with radiative transfer computations to identify key parameters in 3D aerosol-cloud interaction. We found that 3D cloud-induced enhancement depends on optical properties of nearb y clouds as well as wavelength. The enhancement is too large to be ig nored. Associated biased error in 1D aerosol optical thickness retrie val ranges from 50% to 140% depending on wavelength and optical prope rties of nearby clouds as well as aerosol optical thickness. We caution the community to be prudent when applying 1D approximations in comp uting solar radiation in dear regions adjacent to clouds or when usin g traditional retrieved aerosol optical thickness in aerosol indirect effect research.

  2. Evaluation of the Aerosol Type Effect on the Surface Reflectance Retrieval Using Chris/proba Images Over Land

    NASA Astrophysics Data System (ADS)

    Tirelli, C.; Manzo, C.; Curci, G.; Bassani, C.

    2015-04-01

    Surface reflectance has a central role in the analysis of land surface for a broad variety of agricultural, geological and urban studies. An accurate atmospheric correction, obtained by an appropriate selection of aerosol type and loading, is the first requirement for a reliable surface reflectance estimation. The aerosol type is defined by its micro-physical properties, while the aerosol loading is described by optical thickness at 550 nm. The aim of this work is to evaluate the radiative impact of the aerosol model on the surface reflectance obtained from CHRIS (Compact High Resolution Imaging Spectrometer) hyperspectral data over land by using the specifically developed algorithm CHRIS@CRI (CHRIS Atmospherically Corrected Reflectance Imagery) based on the 6SV radiative transfer model. Five different aerosol models have been used: one provided by the AERONET inversion products (used as reference), three standard aerosol models in 6SV, and one obtained from the output of the GEOS-Chem global chemistry-transport model (CTM). As test case the urban site of Bruxelles and the suburban area of Rome Tor Vergata have been considered. The results obtained encourages the use of CTM in operational retrieval and provides an evaluation of the role of the aerosol model in the atmospheric correction process, considering the different microphysical properties impact.

  3. The Relative Effectiveness of Computer Assisted Instruction (CAI) for Teaching Students To Read English.

    ERIC Educational Resources Information Center

    Thompson, Richard A.

    In a review of research on computer assisted instruction (CAI) related to reading, evidence collected provides tentative conclusions about CAI effectiveness. CAI was effective as an instructional medium in the surveyed studies. In a number of instances, CAI groups achieved higher scores than the control groups. Some studies indicated that CAI…

  4. Case studies of aerosol remote sensing with the Airborne Multiangle SpectroPolarimetric Imager (AirMSPI)

    NASA Astrophysics Data System (ADS)

    Diner, D. J.; Xu, F.; Garay, M. J.; Martonchik, J. V.; Kalashnikova, O. V.; Davis, A. B.; Rheingans, B.; Geier, S.; Jovanovic, V.; Bull, M.

    2012-12-01

    The Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) is an 8-band (355, 380, 445, 470, 555, 660, 865, 935 nm) pushbroom camera, measuring polarization in the 470, 660, and 865 nm bands, mounted on a gimbal to acquire multiangular observations over a ±67° along-track range with 10-m spatial resolution across an 11-km wide swath. Among the instrument objectives are exploration of methodologies for combining multiangle, multispectral, polarimetric, and imaging observations to retrieve the optical depth and microphysical properties of tropospheric aerosols. AirMSPI was integrated on NASA's ER-2 high-altitude aircraft in 2010 and has successfully completed a number of flights over land and ocean targets in the Southern California vicinity. In this paper, we present case studies of AirMSPI imagery, interpreted using vector radiative transfer theory. AirMSPI observations over California's Central Valley are compared with model calculations using aerosol properties reported by the Fresno AERONET sunphotometer. Because determination of the radiative impact of different types of aerosols requires accurate attribution of the source of the reflected light along with characterization of the aerosol optical and microphysical properties, we explore the sensitivity of the Fresno measurements to variations in different aerosol properties, demonstrating the value of combining intensity and polarimetry at multiple view angles and spectral bands for constraining particle microphysical properties. Images over ocean to be presented include scenes over nearly cloud-free skies and scenes containing scattered clouds. It is well known that imperfect cloud screening confounds the determination of aerosol impact on radiation; it is perhaps less well appreciated that the effect of cloud reflections in the water can also be problematic. We calculate the magnitude of this effect in intensity and polarization and discuss its potential impact on aerosol retrievals, underscoring the value

  5. Handheld hyperspectral imager for standoff detection of chemical and biological aerosols

    NASA Astrophysics Data System (ADS)

    Hinnrichs, Michele; Jensen, James O.; McAnally, Gerard

    2004-02-01

    Pacific Advanced Technology has developed a small hand held imaging spectrometer, Sherlock, for gas leak and aerosol detection and imaging. The system is based on a patent technique that uses diffractive optics and image processing algorithms to detect spectral information about objects in the scene of the camera (IMSS Image Multi-spectral Sensing). This camera has been tested at Dugway Proving Ground and Dstl Porton Down facility looking at Chemical and Biological agent simulants. The camera has been used to investigate surfaces contaminated with chemical agent simulants. In addition to Chemical and Biological detection the camera has been used for environmental monitoring of green house gases and is currently undergoing extensive laboratory and field testing by the Gas Technology Institute, British Petroleum and Shell Oil for applications for gas leak detection and repair. The camera contains an embedded Power PC and a real time image processor for performing image processing algorithms to assist in the detection and identification of gas phase species in real time. In this paper we will present an over view of the technology and show how it has performed for different applications, such as gas leak detection, surface contamination, remote sensing and surveillance applications. In addition a sampling of the results form TRE field testing at Dugway in July of 2002 and Dstl at Porton Down in September of 2002 will be given.

  6. Photon-counting lidar for aerosol detection and 3D imaging

    NASA Astrophysics Data System (ADS)

    Marino, Richard M.; Richardson, Jonathan; Garnier, Robert; Ireland, David; Bickmeier, Laura; Siracusa, Christina; Quinn, Patrick

    2009-05-01

    Laser-based remote sensing is undergoing a remarkable advance due to novel technologies developed at MIT Lincoln Laboratory. We have conducted recent experiments that have demonstrated the utility of detecting and imaging low-density aerosol clouds. The Mobile Active Imaging LIDAR (MAIL) system uses a Lincoln Laboratory-developed microchip laser to transmit short pulses at 14-16 kHz Pulse Repetition Frequency (PRF), and a Lincoln Laboratory-developed 32x32 Geiger-mode Avalanche-Photodiode Detector (GmAPD) array for singlephoton counting and ranging. The microchip laser is a frequency-doubled passively Q-Switched Nd:YAG laser providing an average transmitted power of less than 64 milli-Watts. When the avalanche photo-diodes are operated in the Geiger-mode, they are reverse-biased above the breakdown voltage for a time that corresponds to the effective range-gate or range-window of interest. The time-of-flight, and therefore range, is determined from the measured laser transmit time and the digital time value from each pixel. The optical intensity of the received pulse is not measured because the GmAPD is saturated by the electron avalanche. Instead, the reflectivity of the scene, or relative density of aerosols in this case, is determined from the temporally and/or spatially analyzed detection statistics.

  7. Measurement of Aerosol and Cloud Particles with PACS and HARP Hyperangular Imaging Polarimeters

    NASA Astrophysics Data System (ADS)

    Martins, J.; Fernandez-Borda, R.; Remer, L. A.; Sparr, L.; Buczkowski, S.; Munchak, L. A.

    2013-12-01

    PACS is new hyper-angular imaging polarimeter for aeorosol and cloud measurerents designed to meet the requirements of the proposed ACE decadal survey mission. The full PACS system consists of three wide field of view (110deg cross track) telescopes covering the UV, VNIR, and SWIR spectral ranges with angular coverage between +55 deg forward to -55deg backwards. The angular density can be selected to cover up to 100 different viewing angles at selected wavelengths. PACS_VNIR is a prototype airborne instrument designed to demonstrate PACS capability by deploying just one of the three wavelength modules of the full PACS. With wavelengths at 470, 550, 675, 760 and 875nm, PACS_VNIR flew for the first time during the PODEX experiment in January/February 2013 aboard the NASA ER-2 aircraft. PACS SWIR (1.64, 1.88, 2.1, and 2.25um) is currently under construction and should be operational in the lab by Fall/2013. PACS_ UV has been fully designed, but is not yet under construction. During the PODEX flights PACS_VNIR collected data for aerosol and clouds over variable surface types including, water, vegetation, urban areas, and snow. The data is currently being calibrated, geolocated and prepared for the inversion of geophysical parameters including water cloud size distribution and aerosol microphysical parameters. The large density of angles in PACS allows for the characterization of cloudbow features in relatively high spatial resolution in a pixel to pixel basis. This avoids the need for assumptions of cloud homogeneity over any distance. The hyperangle capability also allows detailed observation of cloud ice particles, surface characterization, and optimum selection of the number of angles desired for aerosol retrievals. The aerosol and cloud retrieval algorithms under development for the retrieval of particle microphysical properties from the PACS data will be discussed in this presentation. As an extension of the PACS concept we are currently developing the HARP (Hyper

  8. Aerosol airmass type mapping over the urban Mexico City region from space-based multi-angle imaging

    NASA Astrophysics Data System (ADS)

    Patadia, F.; Kahn, R. A.; Limbacher, J. A.; Burton, S. P.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. W.

    2013-03-01

    Using Multi-angle Imaging SpectroRadiometer (MISR) and sub-orbital measurements from the 2006 INTEX-B/MILAGRO field campaign, in this study we demonstrate MISR's ability to map different aerosol air mass types over the Mexico City metropolitan area. The aerosol air mass distinctions are based on shape, size and single scattering albedo retrievals from the MISR Research Aerosol Retrieval algorithm. In this region, the research algorithm identifies dust-dominated aerosol mixtures based on non-spherical particle shape, whereas spherical biomass burning and urban pollution particles are distinguished by particle size. Four distinct aerosol air masses are identified in the MISR data on 6 March 2006; these results are supported by coincident, airborne high-spectral-resolution lidar (HSRL) measurements. Aerosol optical depth (AOD) gradients are also consistent between the MISR and sub-orbital measurements, but particles having SSA558≈0.7 must be included in the retrieval algorithm to produce good absolute AOD comparisons over pollution-dominated aerosol air masses. The MISR standard V22 AOD product, at 17.6 km resolution, captures the observed AOD gradients qualitatively, but retrievals at this coarse spatial scale and with limited spherical absorbing particle options underestimate AOD and do not retrieve particle properties adequately over this complex urban region. However, we demonstrate how AOD and aerosol type mapping can be accomplished with MISR data over urban regions, provided the retrieval is performed at sufficiently high spatial resolution, and with a rich enough set of aerosol components and mixtures.

  9. Aerosol-induced lung injuries observed by synchrotron radiation X-ray phase-contrast imaging technique

    NASA Astrophysics Data System (ADS)

    Yue, Weisheng; Zhang, Guilin; Liu, Ping; Sun, Jianqi; Hwu, Yeukuang; Je, Jung Ho; Tan, Mingguang; Li, Yan

    2007-09-01

    Adverse health effects are associated with the inhalation of a variety of atmospheric particles. To study the lung injuries caused by aerosol PM2.5, synchrotron radiation (SR) X-ray phase-contrast imaging technique was used. Nude mice were inoculated with PM2.5 samples collected from suburban area (JD), industrial area (BS) and traffic tunnel (DPQ) of Shanghai. From X-ray phase-contrast images of lung tissues, apart from blood vessels and structures of alveoli, even hemorrhage spots of several microns caused by the inflammation were clearly observed. The studies showed that the PM2.5 samples collected from the traffic tunnel (DPQ) produced higher level of lung injury, followed by the aerosol samples collected from industrial area (BS) and suburban area (JD). Our studies also helped us to understand the process of lung injuries caused by aerosol particles.

  10. Chemical Imaging of Ambient Aerosol Particles: Observational Constraints on Mixing State Parameterization

    SciTech Connect

    O'Brien, Rachel; Wang, Bingbing; Laskin, Alexander; Riemer, Nicole; West, Matthew; Zhang, Qi; Sun, Yele; Yu, Xiao-Ying; Alpert, Peter A.; Knopf, Daniel A.; Gilles, Mary K.; Moffet, Ryan

    2015-09-28

    A new parameterization for quantifying the mixing state of aerosol populations has been applied for the first time to samples of ambient particles analyzed using spectro-microscopy techniques. Scanning transmission x-ray microscopy/near edge x-ray absorption fine structure (STXM/NEXAFS) and computer controlled scanning electron microscopy/energy dispersive x-ray spectroscopy (CCSEM/EDX) were used to probe the composition of the organic and inorganic fraction of individual particles collected on June 27th and 28th during the 2010 Carbonaceous Aerosols and Radiative Effects (CARES) study in the Central Valley, California. The first field site, T0, was located in downtown Sacramento, while T1 was located near the Sierra Nevada Mountains. Mass estimates of the aerosol particle components were used to calculate mixing state metrics, such as the particle-specific diversity, bulk population diversity, and mixing state index, for each sample. Both microscopy imaging techniques showed more changes over these two days in the mixing state at the T0 site than at the T1 site. The STXM data showed evidence of changes in the mixing state associated with a build-up of organic matter confirmed by collocated measurements and the largest impact on the mixing state was due to an increase in soot dominant particles during this build-up. The CCSEM/EDX analysis showed the presence of two types of particle populations; the first was dominated by aged sea salt particles and had a higher mixing state index (indicating a more homogeneous population), the second was dominated by carbonaceous particles and had a lower mixing state index.

  11. The Earth Clouds and Radiation Explorer (EarthCARE) Mission: Cloud and Aerosol Lidar and Imager algorithms.

    NASA Astrophysics Data System (ADS)

    Donovan, David; van Zadelhoff, Gerd-Jan; Wandinger, Ulla; Hünerbein, Anjah; Fischer, Jurgen; von Bismarck, Jonas; Eisinger, Michael; Lajas, Dulce; Wehr, Tobias

    2015-04-01

    The value of multi-sensor remote sensing applied to clouds and aerosol has become clear in recent years. For example, combinations of instruments including passive radiometers, lidars and cloud radars have proved invaluable for their ability to retrieve profiles of cloud macrophysical and microphysical properties. This is amply illustrated by various results from the US-DoE ARM (and similar) surface sites as well as results from data collected by sensors aboard the A-train satellites CloudSat, CALIPSO, and Terra. The Earth Clouds Aerosol and Radiation Explorer (EarthCARE) mission is a combined ESA/JAXA mission to be launched in 2018 which has been designed with sensor-synergy playing a key role. The mission consists of a cloud-profiling radar (CPR), a high-spectral resolution cloud/aerosol lidar (ATLID), a cloud/aerosol multi-spectral imager (MSI), and a three-view broad-band radiometer (BBR). The mission will deliver cloud, aerosol and radiation products focusing on horizontal scales ranging from 1 km to 10 km. EarthCARE data will be used in multiple ways ranging from model evaluation studies, to GCM-orientated cloud microphysical property parameterization development, to data assimilation activities. Recently a number of activities, funded by ESA, have kicked-off which will ultimately deliver operational algorithms for EarthCARE. One of these activities is the "Atmospheric Products from Imager and Lidar" (APRIL) project which focuses on the development of lidar, imager and combined lidar-imager cloud and aerosol algorithms. In this presentation an overview of the APRIL algorithms within the wider context of the planned EarthCARE processing chain will be given.

  12. Preliminary Study on Remote Sensing of Aerosol Optical Properties over Ocean around the Korean Peninsula from Geostationary Ocean Color Imager

    NASA Astrophysics Data System (ADS)

    Lee, J.; Kim, J.; Ryu, J.; Ahn, Y.

    2009-12-01

    An aerosol retrieval algorithm for the first Geostationary Ocean Color Imager (GOCI) to be launched in September 2009 onboard the Communication, Ocean, and Meteorological Satellite (COMS) is presented by applying the algorithm to the MODIS data. Over clear water, the algorithm retrieves aerosol optical depth (AOD) and fine-mode fraction (FMF) together with aerosol type in 1 km × 1 km resolution. Over turbid water, only AOD is retrieved due to uncertainty in bright surface reflectance. To develop optimized algorithm for the target area of GOCI, optical properties of aerosol are analyzed from extensive observation of AERONET sunphotometer to generate lookup table. Surface reflectance of turbid water is determined from 30-day composite of Rayleigh- and gas corrected reflectances. The comparison of retrieved AOD with those of MODIS collection 5 and AERONET sunphotometer observations shows reliable results. Especially, the application of turbid water algorithm significantly increases the accuracy in retrieving AOD at Anmyon station. The sensitivity study between MODIS and GOCI instruments in terms of relative sensitivity and scattering angle shows promising applicability of the developed algorithm to real GOCI data. Hourly retrieval of aerosol optical properties from GOCI can be used in many ways, especially for environmental monitoring and to study the effect of aerosol in climate change over the East Asia which is one of the most polluted regions over the globe.

  13. Clinical ventilation imaging with /sup 113m/In aerosol: a comparison with /sup 81m/Kr

    SciTech Connect

    Fazio, F.; Wollmer, P.; Lavender, J.P.; Barr, M.M.

    1982-04-01

    Following routine ventilation (/sup 81m/Kr)/perfusion (/sup 99m/Tc) scanning, we obtained aerosol ventilation scans using a solution of /sup 113m/In albumin and a settling-bag system. The large-volume settling bag reduces deposition of particles in the large airway by removing large droplets. The patient inhales the aerosol with 5-10 min of tidal breathing, then lung scans are obtained on a gamma camera. The energy of /sup 113m/In allows the ventilation scanning to be performed after /sup 99m/Tc perfusion scanning. Semiquantitative scoring of regional ventilation showed a close correlation (r . 0.97) between /sup 81m/Kr and /sup 113m/In aerosol ventilation scans. The aerosol technique gave a slight underestimation of ventilation compared with /sup 81m/Kr. This is explained by a slightly reduced penetration of particles to the periphery of the lung in patients with severe obstructive airways disease. In all cases, however, the aerosol did visualize all ventilated regions. The results indicate that this readily available aerosol technique can be useful for clinical ventilation imaging in multiple views.

  14. Feasibility of anomaly occurrence in aerosols time series obtained from MODIS satellite images during hazardous earthquakes

    NASA Astrophysics Data System (ADS)

    Akhoondzadeh, Mehdi; Jahani Chehrebargh, Fatemeh

    2016-09-01

    Earthquake is one of the most devastating natural disasters that its prediction has not materialized comprehensive. Remote sensing data can be used to access information which is closely related to an earthquake. The unusual variations of lithosphere, atmosphere and ionosphere parameters before the main earthquakes are considered as earthquake precursors. To date the different precursors have been proposed. This paper examines one of the parameters which can be derived from satellite imagery. The mentioned parameter is Aerosol Optical Depth (AOD) that this article reviews its relationship with earthquake. Aerosol parameter can be achieved through various methods such as AERONET ground stations or using satellite images via algorithms such as the DDV (Dark Dense Vegetation), Deep Blue Algorithm and SYNTAM (SYNergy of Terra and Aqua Modis). In this paper, by analyzing AOD's time series (derived from MODIS sensor on the TERRA platform) for 16 major earthquakes, seismic anomalies were observed before and after earthquakes. Before large earthquakes, rate of AOD increases due to the pre-seismic changes before the strong earthquake, which produces gaseous molecules and therefore AOD increases. Also because of aftershocks after the earthquake there is a significant change in AOD due to gaseous molecules and dust. These behaviors suggest that there is a close relationship between earthquakes and the unusual AOD variations. Therefore the unusual AOD variations around the time of earthquakes can be introduced as an earthquake precursor.

  15. Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight.

    PubMed

    Loh, N D; Hampton, C Y; Martin, A V; Starodub, D; Sierra, R G; Barty, A; Aquila, A; Schulz, J; Lomb, L; Steinbrener, J; Shoeman, R L; Kassemeyer, S; Bostedt, C; Bozek, J; Epp, S W; Erk, B; Hartmann, R; Rolles, D; Rudenko, A; Rudek, B; Foucar, L; Kimmel, N; Weidenspointner, G; Hauser, G; Holl, P; Pedersoli, E; Liang, M; Hunter, M S; Hunter, M M; Gumprecht, L; Coppola, N; Wunderer, C; Graafsma, H; Maia, F R N C; Ekeberg, T; Hantke, M; Fleckenstein, H; Hirsemann, H; Nass, K; White, T A; Tobias, H J; Farquar, G R; Benner, W H; Hau-Riege, S P; Reich, C; Hartmann, A; Soltau, H; Marchesini, S; Bajt, S; Barthelmess, M; Bucksbaum, P; Hodgson, K O; Strüder, L; Ullrich, J; Frank, M; Schlichting, I; Chapman, H N; Bogan, M J

    2012-06-28

    The morphology of micrometre-size particulate matter is of critical importance in fields ranging from toxicology to climate science, yet these properties are surprisingly difficult to measure in the particles' native environment. Electron microscopy requires collection of particles on a substrate; visible light scattering provides insufficient resolution; and X-ray synchrotron studies have been limited to ensembles of particles. Here we demonstrate an in situ method for imaging individual sub-micrometre particles to nanometre resolution in their native environment, using intense, coherent X-ray pulses from the Linac Coherent Light Source free-electron laser. We introduced individual aerosol particles into the pulsed X-ray beam, which is sufficiently intense that diffraction from individual particles can be measured for morphological analysis. At the same time, ion fragments ejected from the beam were analysed using mass spectrometry, to determine the composition of single aerosol particles. Our results show the extent of internal dilation symmetry of individual soot particles subject to non-equilibrium aggregation, and the surprisingly large variability in their fractal dimensions. More broadly, our methods can be extended to resolve both static and dynamic morphology of general ensembles of disordered particles. Such general morphology has implications in topics such as solvent accessibilities in proteins, vibrational energy transfer by the hydrodynamic interaction of amino acids, and large-scale production of nanoscale structures by flame synthesis.

  16. Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight.

    PubMed

    Loh, N D; Hampton, C Y; Martin, A V; Starodub, D; Sierra, R G; Barty, A; Aquila, A; Schulz, J; Lomb, L; Steinbrener, J; Shoeman, R L; Kassemeyer, S; Bostedt, C; Bozek, J; Epp, S W; Erk, B; Hartmann, R; Rolles, D; Rudenko, A; Rudek, B; Foucar, L; Kimmel, N; Weidenspointner, G; Hauser, G; Holl, P; Pedersoli, E; Liang, M; Hunter, M S; Hunter, M M; Gumprecht, L; Coppola, N; Wunderer, C; Graafsma, H; Maia, F R N C; Ekeberg, T; Hantke, M; Fleckenstein, H; Hirsemann, H; Nass, K; White, T A; Tobias, H J; Farquar, G R; Benner, W H; Hau-Riege, S P; Reich, C; Hartmann, A; Soltau, H; Marchesini, S; Bajt, S; Barthelmess, M; Bucksbaum, P; Hodgson, K O; Strüder, L; Ullrich, J; Frank, M; Schlichting, I; Chapman, H N; Bogan, M J

    2012-06-28

    The morphology of micrometre-size particulate matter is of critical importance in fields ranging from toxicology to climate science, yet these properties are surprisingly difficult to measure in the particles' native environment. Electron microscopy requires collection of particles on a substrate; visible light scattering provides insufficient resolution; and X-ray synchrotron studies have been limited to ensembles of particles. Here we demonstrate an in situ method for imaging individual sub-micrometre particles to nanometre resolution in their native environment, using intense, coherent X-ray pulses from the Linac Coherent Light Source free-electron laser. We introduced individual aerosol particles into the pulsed X-ray beam, which is sufficiently intense that diffraction from individual particles can be measured for morphological analysis. At the same time, ion fragments ejected from the beam were analysed using mass spectrometry, to determine the composition of single aerosol particles. Our results show the extent of internal dilation symmetry of individual soot particles subject to non-equilibrium aggregation, and the surprisingly large variability in their fractal dimensions. More broadly, our methods can be extended to resolve both static and dynamic morphology of general ensembles of disordered particles. Such general morphology has implications in topics such as solvent accessibilities in proteins, vibrational energy transfer by the hydrodynamic interaction of amino acids, and large-scale production of nanoscale structures by flame synthesis. PMID:22739316

  17. Handheld hyperspectral imager for standoff detection of chemical and biological aerosols

    NASA Astrophysics Data System (ADS)

    Hinnrichs, Michele; Jensen, James O.; McAnally, Gerard

    2004-08-01

    Pacific Advanced Technology has developed a small hand held imaging spectrometer, Sherlock, for gas leak and aerosol detection and imaging. The system is based on a patented technique, (IMSS Image Multi-spectral Sensing), that uses diffractive optics and image processing algorithms to detect spectral information about objects in the scene of the camera. This cameras technology has been tested at Dugway Proving Ground and Dstl Porton Down facilities looking at Chemical and Biological agent simulants. In addition to Chemical and Biological detection, the camera has been used for environmental monitoring of green house gases and is currently undergoing extensive laboratory and field testing by the Gas Technology Institute, British Petroleum and Shell Oil for applications for gas leak detection and repair. In this paper we will present some of the results from the data collection at the TRE test at Dugway Proving Ground during the summer of 2002 and laboratory testing at the Dstl facility at Porton Down in the UK in the fall of 2002.

  18. Impacts of Cross-Platform Vicarious Calibration on the Deep Blue Aerosol Retrievals for Moderate Resolution Imaging Spectroradiometer Aboard Terra

    NASA Technical Reports Server (NTRS)

    Jeong, Myeong-Jae; Hsu, N. Christina; Kwiatkowska, Ewa J.; Franz, Bryan A.; Meister, Gerhard; Salustro, Clare E.

    2012-01-01

    The retrieval of aerosol properties from spaceborne sensors requires highly accurate and precise radiometric measurements, thus placing stringent requirements on sensor calibration and characterization. For the Terra/Moderate Resolution Imaging Spedroradiometer (MODIS), the characteristics of the detectors of certain bands, particularly band 8 [(B8); 412 nm], have changed significantly over time, leading to increased calibration uncertainty. In this paper, we explore a possibility of utilizing a cross-calibration method developed for characterizing the Terral MODIS detectors in the ocean bands by the National Aeronautics and Space Administration Ocean Biology Processing Group to improve aerosol retrieval over bright land surfaces. We found that the Terra/MODIS B8 reflectance corrected using the cross calibration method resulted in significant improvements for the retrieved aerosol optical thickness when compared with that from the Multi-angle Imaging Spectroradiometer, Aqua/MODIS, and the Aerosol Robotic Network. The method reported in this paper is implemented for the operational processing of the Terra/MODIS Deep Blue aerosol products.

  19. NEW TITANIUM ISOTOPE DATA FOR ALLENDE AND EFREMOVKA CAIs

    SciTech Connect

    Leya, Ingo; Schoenbaechler, Maria; Kraehenbuehl, Urs; Halliday, Alex N.

    2009-09-10

    We measured the titanium (Ti) isotope composition, i.e., {sup 50}Ti/{sup 47}Ti, {sup 48}Ti/{sup 47}Ti, and {sup 46}Ti/{sup 47}Ti, in five calcium-rich-aluminum-rich refractory inclusions (CAIs) from the oxidized CV3 chondrite Allende and in two CAIs from the reduced CV3 chondrite Efremovka. Our data indicate that CAIs are enriched in {sup 50}Ti/{sup 47}Ti and {sup 46}Ti/{sup 47}Ti and are slightly depleted in {sup 48}Ti/{sup 47}Ti compared to normal Ti defined by ordinary chondrites, eucrites, ureilites, mesosiderites, Earth, Moon, and Mars. Some CAIs have an additional {sup 50}Ti excess of {approx}8{epsilon} relative to bulk carbonaceous chondrites, which are enriched in {sup 50}Ti by {approx}2{epsilon} relative to terrestrial values, leading to a total excess of {approx}10{epsilon}. This additional {sup 50}Ti excess is correlated with nucleosynthetic anomalies found in {sup 62}Ni and {sup 96}Zr, all indicating an origin from a neutron-rich stellar source. Bulk carbonaceous chondrites show a similar trend, however, the extent of the anomalies is either less than or similar to the smallest anomalies seen in CAIs. Mass balance calculations suggest that bulk Allende Ti possibly consists of a mixture of at least two Ti components, anomalous Ti located in CAIs and a normal component possibly for matrix and chondrules. This argues for a heterogeneous distribution of Ti isotopes in the solar system. The finding that anomalous Ti is concentrated in CAIs suggests that CAIs formed in a specific region of the solar system and were, after their formation, not homogeneously redistributed within the solar system. Combining the CAI data with improved model predictions for early solar system irradiation effects indicates that a local production scenario for the relatively short lived radionuclides can be excluded, because the production of, e.g., {sup 10}Be, {sup 26}Al, and {sup 41}Ca, would result in a significant collateral shift in Ti isotopes, which is not seen in the

  20. Improved aerosol retrieval algorithm using Landsat images and its application for PM10 monitoring over urban areas

    NASA Astrophysics Data System (ADS)

    Luo, Nana; Wong, Man Sing; Zhao, Wenji; Yan, Xing; Xiao, Fei

    2015-02-01

    Aerosol retrieval using MODerate resolution Imaging Spectroradiometer (MODIS) has been well researched over the past decade. However, the application is limited to global- and regional-scale studies, which may not be applicable for urban areas due to its low spatial resolution. To overcome the limitation, this paper proposed an improved aerosol retrieval algorithm for Landsat images (ImAero-Landsat) at spatial resolution of 30 m. This ImAero-Landsat algorithm has been improved in the following two aspects: (i) it does not require a comprehensive look up table and thus it is more efficient in AOT retrieval; and (ii) it can be operated in both bright and dark surfaces. The derived aerosol optical thickness (AOT) images were validated with AErosol RObotic NETwork (AERONET) measurements as well as MODIS MOD04 AOT products. Small root mean square errors (RMSEs) of 0.11 and 0.14 and mean absolute difference (MAD) of 0.07 and 0.11 between ImAero-Landsat AOT, with MODIS MOD04 and AERONET products were observed. By correlating with ground based PM10 concentrations, the ImAero-Landsat method outperforms (r2 = 0.32) than MOD04 AOT products (r2 = 0.23). In addition, the accuracy of estimating PM10 can be improved to r2 = 0.55 when the derived AOT was integrated with meteorological parameters. The accuracy is similar to the results derived from AERONET AOT (r2 = 0.62). This study offers a simple and accurate method to investigate aerosol optical thickness at detailed city-scale. Environmental authorities may use the derived methods for deriving aerosol distribution maps and pinpointing the sources of pollutants in urban areas.

  1. Remote sensing of cloud, aerosol and water vapor properties from the Moderate Resolution Imaging Spectrometer (MODIS)

    NASA Technical Reports Server (NTRS)

    King, M. D.

    1992-01-01

    The Moderate Resolution Imaging Spectrometer (MODIS) is an Earth-viewing sensor being developed as a facility instrument for the Earth Observing System (EOS) to be launched in the late 1990s. MODIS consists of two separate instruments that scan a swath width sufficient to provide nearly complete global coverage every two days from a polar-orbiting, Sun-synchronous, platform at an altitude of 705 km. Of primary interest for studies of atmospheric physics is the MODIS-N (nadir) instrument which will provide images in 36 spectral bands between 0.415 and 14.235 micrometers with spatial resoulutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean and atmosperhic processes. The intent of this lecture is to describe the current status of MODIS-N and its companion instrument MODIS-T (tilt), a tiltable cross-track scanning radiometer with 32 uniformly spaced channels between 0.410 and 0.875 micrometers, and to describe the physical principles behind the development of MODIS for the remote sensing of atmospheric properties. Primary emphasis will be placed on the main atmospheric applications of determining the optical, microphysical and physical properties of clouds and aerosol particles form spectral-reflection and thermal-emission measurements. In addition to cloud and aerosol properties, MODIS-N will be utilized for the determination of the total precipitable water vapor over land and atmospheric stability. The physical principles behind the determination of each of these atmospheric products will be described herein.

  2. Bridging the Gap Between Science and Clinical Efficacy: Physiology, Imaging, and Modeling of Aerosols in the Lung.

    PubMed

    Darquenne, Chantal; Fleming, John S; Katz, Ira; Martin, Andrew R; Schroeter, Jeffry; Usmani, Omar S; Venegas, Jose; Schmid, Otmar

    2016-04-01

    Development of a new drug for the treatment of lung disease is a complex and time consuming process involving numerous disciplines of basic and applied sciences. During the 2015 Congress of the International Society for Aerosols in Medicine, a group of experts including aerosol scientists, physiologists, modelers, imagers, and clinicians participated in a workshop aiming at bridging the gap between basic research and clinical efficacy of inhaled drugs. This publication summarizes the current consensus on the topic. It begins with a short description of basic concepts of aerosol transport and a discussion on targeting strategies of inhaled aerosols to the lungs. It is followed by a description of both computational and biological lung models, and the use of imaging techniques to determine aerosol deposition distribution (ADD) in the lung. Finally, the importance of ADD to clinical efficacy is discussed. Several gaps were identified between basic science and clinical efficacy. One gap between scientific research aimed at predicting, controlling, and measuring ADD and the clinical use of inhaled aerosols is the considerable challenge of obtaining, in a single study, accurate information describing the optimal lung regions to be targeted, the effectiveness of targeting determined from ADD, and some measure of the drug's effectiveness. Other identified gaps were the language and methodology barriers that exist among disciplines, along with the significant regulatory hurdles that need to be overcome for novel drugs and/or therapies to reach the marketplace and benefit the patient. Despite these gaps, much progress has been made in recent years to improve clinical efficacy of inhaled drugs. Also, the recent efforts by many funding agencies and industry to support multidisciplinary networks including basic science researchers, R&D scientists, and clinicians will go a long way to further reduce the gap between science and clinical efficacy. PMID:26829187

  3. Magnesium, Silicon, and Oxygen Isotopic Consequences of CAI Evaporation and Inversion for Primordial Melt Compositions

    NASA Astrophysics Data System (ADS)

    Young, E. D.; Shahar, A.

    2012-03-01

    We show how realistic activity-composition relationships in CMAS melts can be used to invert silicon- and magnesium-isotope ratios for evaporation histories of CAIs. Results suggest igneous CAIs were indeed condensates from a solar gas.

  4. CAI for the Developmentally Handicapped: Nine Years of Progress.

    ERIC Educational Resources Information Center

    Hallworth, H. J.; Brebner, Ann

    Initiated nine years ago by the University of Calgary Faculty of Education Computer Applications Unit in cooperation with the nearby Vocational and Rehabilitation Research Institute (VRRI), this project uses computer assisted instruction (CAI) to teach social and vocational skills to developmentally handicapped young adults, many of whom also have…

  5. Conjunctival mucin deficiency in complete androgen insensitivity syndrome (CAIS).

    PubMed

    Mantelli, Flavio; Moretti, Costanzo; Micera, Alessandra; Bonini, Stefano

    2007-06-01

    Sex steroid hormones are essential for a healthy ocular surface and the androgen receptor impairment found in patients with complete androgen insensitivity syndrome (CAIS) has been described to cause meibomian gland dysfunction and functional dry eye for lipid tear film layer instability. However, it has not been reported if the mucous layer is also affected. A 37-year-old CAIS patient with persistent symptoms of dry eye underwent ophthalmological examination and was evaluated for qualitative and quantitative tear function tests and conjunctival cytology. Samples obtained from the conjunctival epithelium were stained for histology and immunohistochemistry and compared with three age-matched female controls. Western blot and relative real-time RT-PCR for MUC1 and MUC5AC were also performed on these samples. Immunohistochemistry, Western blot and relative real-time RT-PCR showed a decrease in the expression of MUC1 and MUC5AC in CAIS. Changes in the tear film mucous layer were accompanied by a reduction in the tear film break up time test. This is the first report describing mucous layer alteration associated with androgen receptor impairment. Decreased mucin levels contribute in explaining the tear film instability in CAIS and should be considered an additional cause of dry eye in sex steroid hormone pathology.

  6. An Intelligent CAI Monitor and Generative Tutor. Interim Report.

    ERIC Educational Resources Information Center

    Koffman, Elliot B.; And Others

    Design techniques for generative computer-assisted-instructional (CAI) systems are described in this report. These are systems capable of generating problems for students and of deriving and monitoring solutions; problem difficulty, instructional pace, and depth of monitoring are all individually tailored and parts of the solution algorithms can…

  7. Introductory CAI Dialogue in Differential Calculus for Freshman Physics

    ERIC Educational Resources Information Center

    Kalman, C. S.; And Others

    1974-01-01

    A project on computer based dialogue for freshmen is described and evaluated. The dialogue utilizes a CAI language written in Fortran that allows a designer to easily write and edit questions at his own desk without the use of a terminal. (Author/DT)

  8. CAI: Overcoming Attitude Barriers of Prospective Primary Teachers. Final Report.

    ERIC Educational Resources Information Center

    Kockler, Lois H.

    During each of two school quarters, approximately 60 college students enrolled in a mathematics course were randomly assigned to an experimental group or a control group. The control group received instruction by the lecture method only; the experimental group received the same instruction, except that six computer-assisted instruction (CAI) units…

  9. CAISYS-8- A CAI Language Developed For A Minicomputer.

    ERIC Educational Resources Information Center

    Holm, Cheryl; And Others

    The University of Texas Medical Branch developed a minicomputer-based computer-assisted instruction (CAI) system which employed a teacher oriented software package called CAISYS-8, consisting of a highly modularized teaching compiler and operating system. CAISYS-8 used instructional quanta which generalized the flow of information to and from the…

  10. A Comparison of Student Option Versus Program Controlled CAI Training.

    ERIC Educational Resources Information Center

    McCann, Patrick H.; And Others

    A research study compared two methods for individualizing computer-assisted instruction (CAI) training and evaluated the effect of providing a lesson narrative before training. A 2x2 factorial design was used with 96 Navy trainees in the Basic Electricity/Electronics School. The two pretraining conditions were: 1) a narrative overview read before…

  11. Distribution and Origin of 36Cl In Allende CAIs

    SciTech Connect

    Matzel, J P; Jacobsen, B; Hutcheon, I D; Krot, A N; Nagashima, K; Yin, Q; Ramon, E C; Weber, P; Wasserburg, G J

    2009-12-11

    The abundance of short-lived radionuclides (SLRs) in early solar system materials provide key information about their nucleosynthetic origin and can constrain the timing of early solar system events. Excesses of {sup 36}S ({sup 36}S*) correlated with {sup 35}Cl/{sup 34}S ratios provide direct evidence for in situ decay of {sup 36}Cl ({tau}{sub 1/2} {approx} 0.3 Ma) and have been reported in sodalite (Na{sub 8}Al{sub 6}Si{sub 6}O{sub 24}Cl{sub 2}) and wadalite (Ca{sub 6}Al{sub 5}Si{sub 2}O{sub 16}Cl{sub 3}) in CAIs and chondrules from the Allende and Ningqiang CV carbonaceous chondrites. While previous studies demonstrate unequivocally that {sup 36}Cl was extant in the early solar system, no consensus on the origin or initial abundance of {sup 36}Cl has emerged. Understanding the origin of {sup 36}Cl, as well as the reported variation in the initial {sup 36}Cl/{sup 35}Cl ratio, requires addressing when, where and how chlorine was incorporated into CAIs and chondrules. These factors are key to distinguishing between stellar nucleosynthesis or energetic particle irradiation for the origin of {sup 36}Cl. Wadalite is a chlorine-rich secondary mineral with structural and chemical affinities to grossular. The high chlorine ({approx}12 wt%) and very low sulfur content (<<0.01 wt%) make wadalite ideal for studies of the {sup 36}Cl-{sup 36}S system. Wadalite is present in Allende CAIs exclusively in the interior regions either in veins crosscutting melilite or in zones between melilite and anorthite associated with intergrowths of grossular, monticellite, and wollastonite. Wadalite and sodalite most likely resulted from open-system alteration of primary minerals with a chlorine-rich fluid phase. We recently reported large {sup 36}S* correlated with {sup 35}Cl/{sup 34}S in wadalite in Allende Type B CAI AJEF, yielding a ({sup 36}Cl/{sup 35}Cl){sub 0} ratio of (1.7 {+-} 0.3) x 10{sup -5}. This value is the highest reported {sup 36}Cl/{sup 35}Cl ratio and is {approx}5 times

  12. Evaluation of applicability of high-resolution multiangle imaging photo-polarimetric observations for aerosol atmospheric correction

    NASA Astrophysics Data System (ADS)

    Kalashnikova, Olga; Garay, Michael; Xu, Feng; Diner, David; Seidel, Felix

    2016-07-01

    Multiangle spectro-polarimetric measurements have been advocated as an additional tool for better understanding and quantifying the aerosol properties needed for atmospheric correction for ocean color retrievals. The central concern of this work is the assessment of the effects of absorbing aerosol properties on remote sensing reflectance measurement uncertainty caused by neglecting UV-enhanced absorption of carbonaceous particles and by not accounting for dust nonsphericity. In addition, we evaluate the polarimetric sensitivity of absorbing aerosol properties in light of measurement uncertainties achievable for the next generation of multi-angle polarimetric imaging instruments, and demonstrate advantages and disadvantages of wavelength selection in the UV/VNIR range. In this work a vector Markov Chain radiative transfer code including bio-optical models was used to quantitatively evaluate in water leaving radiances between atmospheres containing realistic UV-enhanced and non-spherical aerosols and the SEADAS carbonaceous and dust-like aerosol models. The phase matrices for the spherical smoke particles were calculated using a standard Mie code, while those for non-spherical dust particles were calculated using the numerical approach developed for modeling dust for the AERONET network of ground-based sunphotometers. As a next step, we have developed a retrieval code that employs a coupled Markov Chain (MC) and adding/doubling radiative transfer method for joint retrieval of aerosol properties and water leaving radiance from Airborne Multiangle SpectroPolarimetric Imager-1 (AirMSPI-1) polarimetric observations. The AirMSPI-1 instrument has been flying aboard the NASA ER-2 high altitude aircraft since October 2010. AirMSPI typically acquires observations of a target area at 9 view angles between ±67° at 10 m resolution. AirMSPI spectral channels are centered at 355, 380, 445, 470, 555, 660, and 865 nm, with 470, 660, and 865 reporting linear polarization. We

  13. Effectiveness of CAI Package on Achievement in Physics of IX Standard Students

    ERIC Educational Resources Information Center

    Maheswari, I. Uma; Ramakrishnan, N.

    2015-01-01

    The present study is an experimental one in nature, to find out the effectiveness of CAI package on in Physics of IX std. students. For this purpose a CAI package was developed and validated. The validated CAI package formed an independent variable of this study. The dependent variable is students' achievements in physics content. In order to find…

  14. Harvard University Computer-Aided Instruction (CAI) Laboratory. Technical Report Number 6.

    ERIC Educational Resources Information Center

    Stolurow, Lawrence M.; Peterson, Theodore I.

    This report is a detailed description of the Harvard CAI Laboratory, including its history, organization, functions, staffing, programs and support. Discussed are materials relating to CAI in general, such as psychological research, modes of instruction, advantages and implementation of CAI. Reviewed also are specific projects of this facility. A…

  15. Characterization of Meteorites by Focused Ion Beam Sectioning: Recent Applications to CAIs and Primitive Meteorite Matrices

    NASA Technical Reports Server (NTRS)

    Christoffersen, Roy; Keller, Lindsay P.; Han, Jangmi; Rahman, Zia; Berger, Eve L.

    2015-01-01

    Focused ion beam (FIB) sectioning has revolutionized preparation of meteorite samples for characterization by analytical transmission electron microscopy (TEM) and other techniques. Although FIB is not "non-destructive" in the purest sense, each extracted section amounts to no more than nanograms (approximately 500 cubic microns) removed intact from locations precisely controlled by SEM imaging and analysis. Physical alteration of surrounding material by ion damage, fracture or sputter contamination effects is localized to within a few micrometers around the lift-out point. This leaves adjacent material intact for coordinate geochemical analysis by SIMS, microdrill extraction/TIMS and other techniques. After lift out, FIB sections can be quantitatively analyzed by electron microprobe prior to final thinning, synchrotron x-ray techniques, and by the full range of state-of-the-art analytical field-emission scanning transmission electron microscope (FE-STEM) techniques once thinning is complete. Multiple meteorite studies supported by FIB/FE-STEM are currently underway at NASA-JSC, including coordinated analysis of refractory phase assemblages in CAIs and fine-grained matrices in carbonaceous chondrites. FIB sectioning of CAIs has uncovered epitaxial and other overgrowth relations between corundum-hibonite-spinel consistent with hibonite preceding corundum and/or spinel in non-equilibrium condensation sequences at combinations of higher gas pressures, dust-gas enrichments or significant nebular transport. For all of these cases, the ability of FIB to allow for coordination with spatially-associated isotopic data by SIMS provides immense value for constraining the formation scenarios of the particular CAI assemblage. For carbonaceous chondrites matrix material, FIB has allowed us to obtain intact continuous sections of the immediate outer surface of Murchison (CM2) after it has been experimentally ion processed to simulate solar wind space weathering. The surface

  16. Assessment of capabilities of multiangle imaging photo-polarimetry for atmospheric correction in presence of absorbing aerosols

    NASA Astrophysics Data System (ADS)

    Kalashnikova, O. V.; Garay, M. J.; Xu, F.; Seidel, F. C.; Diner, D. J.

    2015-12-01

    Satellite remote sensing of ocean color is a critical tool for assessing the productivity of marine ecosystems and monitoring changes resulting from climatic or environmental influences. Yet water-leaving radiance comprises less than 10% of the signal measured from space, making correction for absorption and scattering by the intervening atmosphere imperative. Traditional ocean color retrieval algorithms utilize a standard set of aerosol models and the assumption of negligible water-leaving radiance in the near-infrared. Modern improvements have been developed to handle absorbing aerosols such as urban particulates in coastal areas and transported desert dust over the open ocean, where ocean fertilization can impact biological productivity at the base of the marine food chain. Even so, imperfect knowledge of the absorbing aerosol optical properties or their height distribution results in well-documented sources of error. In the UV, the problem of UV-enhanced absorption and nonsphericity of certain aerosol types are amplified due to the increased Rayleigh and aerosol optical depth, especially at off-nadir view angles. Multi-angle spectro-polarimetric measurements have been advocated as an additional tool to better understand and retrieve the aerosol properties needed for atmospheric correction for ocean color retrievals. The central concern of the work to be described is the assessment of the effects of absorbing aerosol properties on water leaving radiance measurement uncertainty by neglecting UV-enhanced absorption of carbonaceous particles and by not accounting for dust nonsphericity. In addition, we evaluate the polarimetric sensitivity of absorbing aerosol properties in light of measurement uncertainties achievable for the next generation of multi-angle polarimetric imaging instruments, and demonstrate advantages and disadvantages of wavelength selection in the UV/VNIR range. The phase matrices for the spherical smoke particles were calculated using a standard

  17. Dual-photoelastic-modulator-based polarimetric imaging concept for aerosol remote sensing.

    PubMed

    Diner, David J; Davis, Ab; Hancock, Bruce; Gutt, Gary; Chipman, Russell A; Cairns, Brian

    2007-12-10

    A dual-photoelastic-modulator- (PEM-) based spectropolarimetric camera concept is presented as an approach for global aerosol monitoring from space. The most challenging performance objective is to measure degree of linear polarization (DOLP) with an uncertainty of less than 0.5% in multiple spectral bands, at moderately high spatial resolution, over a wide field of view, and for the duration of a multiyear mission. To achieve this, the tandem PEMs are operated as an electro-optic circular retardance modulator within a high-performance reflective imaging system. Operating the PEMs at slightly different resonant frequencies generates a beat signal that modulates the polarized component of the incident light at a much lower heterodyne frequency. The Stokes parameter ratio q = Q/I is obtained from measurements acquired from each pixel during a single frame, providing insensitivity to pixel responsivity drift and minimizing polarization artifacts that conventionally arise when this quantity is derived from differences in the signals from separate detectors. Similarly, u = U/I is obtained from a different pixel; q and u are then combined to form the DOLP. A detailed accuracy and tolerance analysis for this polarimeter is presented. PMID:18071373

  18. Dual-Photoelastic-Modulator-Based Polarimetric Imaging Concept for Aerosol Remote Sensing

    NASA Technical Reports Server (NTRS)

    Diner, David J.; Davis, Ab; Hancock, Bruce; Gutt, Gary; Chipman, Russell A.; Cairns, Brian

    2007-01-01

    A dual-photoelastic-modulator- (PEM-) based spectropolarimetric camera concept is presented as an approach for global aerosol monitoring from space. The most challenging performance objective is to measure degree of linear polarization (DOLP) with an uncertainty of less than 0.5% in multiple spectral bands, at moderately high spatial resolution, over a wide field of view, and for the duration of a multiyear mission. To achieve this, the tandem PEMs are operated as an electro-optic circular retardance modulator within a high-performance reflective imaging system. Operating the PEMs at slightly different resonant frequencies generates a beat signal that modulates the polarized component of the incident light at a much lower heterodyne frequency. The Stokes parameter ratio q = Q/I is obtained from measurements acquired from each pixel during a single frame, providing insensitivity to pixel responsivity drift and minimizing polarization artifacts that conventionally arise when this quantity is derived from differences in the signals from separate detectors. Similarly, u = U/I is obtained from a different pixel; q and u are then combined to form the DOLP. A detailed accuracy and tolerance analysis for this polarimeter is presented.

  19. Aerosol Particle Size Retrievals from the Compact Reconnaissance Imaging Spectrometer for Mars

    NASA Astrophysics Data System (ADS)

    Guzewich, S.; Smith, M. D.; Wolff, M. J.

    2013-12-01

    During the extended mission of the Mars Reconnaisance Orbiter, the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) has made periodic limb-viewing geometry observations of the Martian atmosphere. Sufficient radiance is typically available to produce a vertical distribution of dust and water ice aerosols from the surface to approximately 50 km altitude. Radiative transfer modeling is conducted to achieve a best fit between the observed and modeled spectrum. The spherical geometry of the limb-viewing geometry is handled using a pseudo-spherical approximation that is computationally efficient and accurate to within a few percent of a Monte Carlo method for the geometries observed. Different particle sizes of dust and water ice have unique extinction coefficients across the visible and near-infrared portion of the spectrum observed by CRISM. We use a wide range of wavelengths across the CRISM spectrum to conduct the retrieval. Here we provide initial results on the retrieval of dust and water ice particle sizes over the duration of the CRISM limb-viewing observations.

  20. CAIs in CO3 Meteorites: Parent Body or Nebular Alteration?

    NASA Astrophysics Data System (ADS)

    Greenwood, R. C.; Hutchison, R.; Huss, G. R.; Hutcheon, I. D.

    1992-07-01

    It is widely held that alteration of Ca Al-rich inclusions (CAIs) in CV3 and CO3 meteorites occurred in the nebula (Hashimoto 1992). The CO3 chondrites, however, appear to define a metamorphic sequence dominated by parent body, and not nebular, metamorphic effects (Scott and Jones, 1990). To investigate the effects of metamorphism on CAIs we have studied inclusions from 4 CO chondrites: Colony (3.0), Felix (3.2), Lance (3.4), and Warrenton (3.6). In a section of Colony (74 mm^2) 81 CAIs, 30-870 micrometers long, comprise 52 nodular spinel-rich inclusions (fragments of Type-A CAI composed largely of spinel), 12 spinel-pyroxene inclusions, 10 melilite-rich inclusions, 2 hibonite-only inclusions, 2 CaAl4O7-bearing inclusions, and 3 spinel-pyroxene- olivine inclusions. Although a find, CAIs in Colony are relatively fresh, melilite in particular being little altered. In 79% of the spinel-bearing inclusions, spinel has <2wt% FeO, which otherwise ranges to 34.8%. Mg isotopic compositions were determined in 5 selected Colony inclusion; evidence of ^26Mg* from decay of ^26Al was found in 4 CAI. A hibonite-only inclusion has the largest ^26Mg* excess, delta^26Mg 32o/oo. Data show no evidence of isotopic disturbance and define a linear array with slope ^26Mg* /^27Al = (3.4+- 0.6) x 10^-5, like that obtained by Davis and Hinton (1986) in a hibonite-bearing spherule from Ornans. Despite Al/Mg ratios of up to 1500, CaAl4O7 in one inclusion shows no evidence of ^26Mg*; ^26Mg* < 4 x 10^-6. All three melilite-bearing inclusions from Colony C21 (angstrom k(sub)8.3-14.3), C56 (angstrom k(sub)10.5-16) and C62 (angstrom k(sub)15-21) show evidence of radiogenic ^26Mg*. Excess ^26Mg positively correlates with the Al/Mg ratios but the data do not define a unique initial value of ^26Al/^27Al. Data for melilite in C21, in particular, show evidence for disturbance of the Al-Mg system, as is common for Allende CAI (Podosek et al. 1991). Melilites in C56 in contrast show no evidence of

  1. Oxygen Isotope Measurements of a Rare Murchison Type A CAI and Its Rim

    NASA Technical Reports Server (NTRS)

    Matzel, J. E. P.; Simon, J. I.; Hutcheon, I. D.; Jacobsen, B.; Simon, S. B.; Grossman, L.

    2013-01-01

    Ca-, Al-rich inclusions (CAIs) from CV chondrites commonly show oxygen isotope heterogeneity among different mineral phases within individual inclusions reflecting the complex history of CAIs in both the solar nebula and/or parent bodies. The degree of isotopic exchange is typically mineral-specific, yielding O-16-rich spinel, hibonite and pyroxene and O-16-depleted melilite and anorthite. Recent work demonstrated large and systematic variations in oxygen isotope composition within the margin and Wark-Lovering rim of an Allende Type A CAI. These variations suggest that some CV CAIs formed from several oxygen reservoirs and may reflect transport between distinct regions of the solar nebula or varying gas composition near the proto-Sun. Oxygen isotope compositions of CAIs from other, less-altered chondrites show less intra-CAI variability and 16O-rich compositions. The record of intra-CAI oxygen isotope variability in CM chondrites, which commonly show evidence for low-temperature aqueous alteration, is less clear, in part because the most common CAIs found in CM chondrites are mineralogically simple (hibonite +/- spinel or spinel +/- pyroxene) and are composed of minerals less susceptible to O-isotopic exchange. No measurements of the oxygen isotope compositions of rims on CAIs in CM chondrites have been reported. Here, we present oxygen isotope data from a rare, Type A CAI from the Murchison meteorite, MUM-1. The data were collected from melilite, hibonite, perovskite and spinel in a traverse into the interior of the CAI and from pyroxene, melilite, anorthite, and spinel in the Wark-Lovering rim. Our objectives were to (1) document any evidence for intra-CAI oxygen isotope variability; (2) determine the isotopic composition of the rim minerals and compare their composition(s) to the CAI interior; and (3) compare the MUM-1 data to oxygen isotope zoning profiles measured from CAIs in other chondrites.

  2. Operational Retrieval of aerosol optical depth over Indian subcontinent and Indian Ocean using INSAT-3D/Imager product validation

    NASA Astrophysics Data System (ADS)

    Mishra, M. K.; Rastogi, G.; Chauhan, P.

    2014-11-01

    Aerosol optical depth (AOD) over Indian subcontinent and Indian Ocean region is derived operationally for the first time from the geostationary earth orbit (GEO) satellite INSAT-3D Imager data at 0.65 μm wavelength. Single visible channel algorithm based on clear sky composites gives larger retrieval error in AOD than other multiple channel algorithms due to errors in estimating surface reflectance and atmospheric property. However, since MIR channel signal is insensitive to the presence of most aerosols, therefore in present study, AOD retrieval algorithm employs both visible (centred at 0.65 μm) and mid-infrared (MIR) band (centred at 3.9 μm) measurements, and allows us to monitor transport of aerosols at higher temporal resolution. Comparisons made between INSAT-3D derived AOD (τI) and MODIS derived AOD (τM) co-located in space (at 1° resolution) and time during January, February and March (JFM) 2014 encompasses 1165, 1052 and 900 pixels, respectively. Good agreement found between τI and τM during JFM 2014 with linear correlation coefficients (R) of 0.87, 0.81 and 0.76, respectively. The extensive validation made during JFM 2014 encompasses 215 co-located AOD in space and time derived by INSAT 3D (τI) and 10 sun-photometers (τA) that includes 9 AERONET (Aerosol Robotic Network) and 1 handheld sun-photometer site. INSAT-3D derived AOD i.e. τI, is found within the retrieval errors of τI = ±0.07 ±0.15τA with linear correlation coefficient (R) of 0.90 and root mean square error equal (RMSE) to 0.06. Present work shows that INSAT-3D aerosol products can be used quantitatively in many applications with caution for possible residual clouds, snow/ice, and water contamination.

  3. Replacement textures in CAI and implications regarding planetary metamorphism

    NASA Technical Reports Server (NTRS)

    Meeker, G. P.; Wasserburg, G. J.; Armstrong, J. T.

    1983-01-01

    Formation by a secondary metamorphic event, rather than primary crystallization from a melt or a sequential nebular condensation, is indicated by textural and chemical features of five coarse grained, Ca- and Al-rich inclusions (CAI) from the Allende meteorite which contain embayed pyroxene surrounded by melilite. It is suggested that the most probable environment for a metamorphic process (requiring the addition of Ca derived from calcite or from the introduction of a fluid phase) is that of a small planetary body, rather than the solar nebula. These results are compatible with O isotopic heterogeneities within CAI, and offer a mechanism for the production of lower temperature alteration phases, together with the rim phases found in these inclusions.

  4. Naval Academy's CAI Project (Computer-Assisted Instruction Project). Final Project Report 1 July 1968 - 30 June 1971.

    ERIC Educational Resources Information Center

    Sandeford, W. H.; And Others

    Aimed at improving officer education through the use of modern technology, a two-pronged computer-assisted instruction (CAI) effort was initiated. CAI techniques and methods utilized in the dual projects (CAI-Teletype and CAI 1500) are discussed under three categories: computational, non-computational, and computer management of instruction.…

  5. Climatology of the aerosol optical depth by components from the Multi-angle Imaging SpectroRadiometer (MISR) and chemistry transport models

    NASA Astrophysics Data System (ADS)

    Lee, Huikyo; Kalashnikova, Olga V.; Suzuki, Kentaroh; Braverman, Amy; Garay, Michael J.; Kahn, Ralph A.

    2016-06-01

    The Multi-angle Imaging SpectroRadiometer (MISR) Joint Aerosol (JOINT_AS) Level 3 product has provided a global, descriptive summary of MISR Level 2 aerosol optical depth (AOD) and aerosol type information for each month over 16+ years since March 2000. Using Version 1 of JOINT_AS, which is based on the operational (Version 22) MISR Level 2 aerosol product, this study analyzes, for the first time, characteristics of observed and simulated distributions of AOD for three broad classes of aerosols: spherical nonabsorbing, spherical absorbing, and nonspherical - near or downwind of their major source regions. The statistical moments (means, standard deviations, and skewnesses) and distributions of AOD by components derived from the JOINT_AS are compared with results from two chemistry transport models (CTMs), the Goddard Chemistry Aerosol Radiation and Transport (GOCART) and SPectral RadIatioN-TrAnSport (SPRINTARS). Overall, the AOD distributions retrieved from MISR and modeled by GOCART and SPRINTARS agree with each other in a qualitative sense. Marginal distributions of AOD for each aerosol type in both MISR and models show considerable high positive skewness, which indicates the importance of including extreme AOD events when comparing satellite retrievals with models. The MISR JOINT_AS product will greatly facilitate comparisons between satellite observations and model simulations of aerosols by type.

  6. Climatology of the aerosol optical depth by components from the Multiangle Imaging SpectroRadiometer (MISR) and a high-resolution chemistry transport model

    NASA Astrophysics Data System (ADS)

    Lee, H.; Kalashnikova, O. V.; Suzuki, K.; Braverman, A.; Garay, M. J.; Kahn, R. A.

    2015-12-01

    The Multi-angle Imaging SpectroRadiometer (MISR) Joint Aerosol (JOINT_AS) Level 3 product provides a global, descriptive summary of MISR Level 2 aerosol optical depth (AOD) and aerosol type information for each month between March 2000 and the present. Using Version 1 of JOINT_AS, which is based on the operational (Version 22) MISR Level 2 aerosol product, this study analyzes, for the first time, characteristics of observed and simulated distributions of AOD for three broad classes of aerosols: non-absorbing, absorbing, and non-spherical - near or downwind of their major source regions. The statistical moments (means, standard deviations, and skewnesses) and distributions of AOD by components derived from the JOINT_AS are compared with results from the SPectral RadIatioN-TrAnSport (SPRINTARS) model, a chemistry transport model (CTM) with very high spatial and temporal resolution. Overall, the AOD distributions of combined MISR aerosol types show good agreement with those from SPRINTARS. Marginal distributions of AOD for each aerosol type in both MISR and SPRINTARS show considerable high positive skewness, which indicates the importance of including extreme AOD events when comparing satellite retrievals with models. The MISR JOINT_AS product will greatly facilitate comparisons between satellite observations and model simulations of aerosols by type.

  7. Silicon Isotopic Fractionation of CAI-like Vacuum Evaporation Residues

    SciTech Connect

    Knight, K; Kita, N; Mendybaev, R; Richter, F; Davis, A; Valley, J

    2009-06-18

    Calcium-, aluminum-rich inclusions (CAIs) are often enriched in the heavy isotopes of magnesium and silicon relative to bulk solar system materials. It is likely that these isotopic enrichments resulted from evaporative mass loss of magnesium and silicon from early solar system condensates while they were molten during one or more high-temperature reheating events. Quantitative interpretation of these enrichments requires laboratory determinations of the evaporation kinetics and associated isotopic fractionation effects for these elements. The experimental data for the kinetics of evaporation of magnesium and silicon and the evaporative isotopic fractionation of magnesium is reasonably complete for Type B CAI liquids (Richter et al., 2002, 2007a). However, the isotopic fractionation factor for silicon evaporating from such liquids has not been as extensively studied. Here we report new ion microprobe silicon isotopic measurements of residual glass from partial evaporation of Type B CAI liquids into vacuum. The silicon isotopic fractionation is reported as a kinetic fractionation factor, {alpha}{sub Si}, corresponding to the ratio of the silicon isotopic composition of the evaporation flux to that of the residual silicate liquid. For CAI-like melts, we find that {alpha}{sub Si} = 0.98985 {+-} 0.00044 (2{sigma}) for {sup 29}Si/{sup 28}Si with no resolvable variation with temperature over the temperature range of the experiments, 1600-1900 C. This value is different from what has been reported for evaporation of liquid Mg{sub 2}SiO{sub 4} (Davis et al., 1990) and of a melt with CI chondritic proportions of the major elements (Wang et al., 2001). There appears to be some compositional control on {alpha}{sub Si}, whereas no compositional effects have been reported for {alpha}{sub Mg}. We use the values of {alpha}Si and {alpha}Mg, to calculate the chemical compositions of the unevaporated precursors of a number of isotopically fractionated CAIs from CV chondrites whose

  8. Quality and compatibility analyses of global aerosol products derived from the advanced very high resolution radiometer and Moderate Resolution Imaging Spectroradiometer

    NASA Astrophysics Data System (ADS)

    Jeong, Myeong-Jae; Li, Zhanqing; Chu, D. Allen; Tsay, Si-Chee

    2005-05-01

    There exist numerous global aerosol products derived from various satellite sensors, but little insight has been gained about their compatibility and quality. This study presents a comparison of two prominent global aerosol products derived over oceans from the advanced very high resolution radiometer (AVHRR) under the Global Aerosol Climatology Project (GACP) (Mishchenko et al., 1999) and the Moderate Resolution Imaging Spectroradiometer (MODIS) (Tanré et al., 1997). The comparisons are for monthly mean aerosol optical thickness (AOT) and Ångström exponent (α) at a spatial resolution of 1 × 1 degree. The two monthly AOT products showed substantial discrepancies, with a tendency of higher values from MODIS than from GACP/AVHRR, especially near the coasts of major aerosol outbreak regions. Individual monthly AOT values have poor correlation, but their regional means are moderately correlated (correlation coefficient 0.5 < R < 1.0). While cloud screening has often been argued to be a major factor explaining large discrepancies, this study shows that differences in aerosol models in the two retrieval algorithms can lead to large discrepancies. Contributions of the size distribution are more significant than the refractive index. The noisiness of the GACP/AVHRR aerosol retrievals seem to be partially influenced by radiometric uncertainties in the AVHRR system, but it is unlikely a major factor to explain the observed systematic discrepancies between the MODIS and GACP/AVHRR AOTs. For α, correlations between MODIS and GACP/AVHRR are lower (0.2 < R < 0.7) than AOT. The MODIS α shows a well-behaved dependence on the AOT contingent upon the aerosol type, while the GACP/AVHRR α has little correlation with the AOT. The high sensitivity in the selection of aerosol models to radiometric errors may be a primary reason for the worse comparison of α. Part of the discrepancies in α is attributed to different aerosol size distributions.

  9. Joint aerosol and water-leaving radiance retrieval from Airborne Multi-angle SpectroPolarimeter Imager

    NASA Astrophysics Data System (ADS)

    Xu, F.; Dubovik, O.; Zhai, P.; Kalashnikova, O. V.; Diner, D. J.

    2015-12-01

    The Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) [1] has been flying aboard the NASA ER-2 high altitude aircraft since October 2010. In step-and-stare operation mode, AirMSPI typically acquires observations of a target area at 9 view angles between ±67° off the nadir. Its spectral channels are centered at 355, 380, 445, 470*, 555, 660*, and 865* nm, where the asterisk denotes the polarimetric bands. In order to retrieve information from the AirMSPI observations, we developed a efficient and flexible retrieval code that can jointly retrieve aerosol and water leaving radiance simultaneously. The forward model employs a coupled Markov Chain (MC) [2] and adding/doubling [3] radiative transfer method which is fully linearized and integrated with a multi-patch retrieval algorithm to obtain aerosol and water leaving radiance/Chl-a information. Various constraints are imposed to improve convergence and retrieval stability. We tested the aerosol and water leaving radiance retrievals using the AirMSPI radiance and polarization measurements by comparing to the retrieved aerosol concentration, size distribution, water-leaving radiance, and chlorophyll concentration to the values reported by the USC SeaPRISM AERONET-OC site off the coast of Southern California. In addition, the MC-based retrievals of aerosol properties were compared with GRASP ([4-5]) retrievals for selected cases. The MC-based retrieval approach was then used to systematically explore the benefits of AirMSPI's ultraviolet and polarimetric channels, the use of multiple view angles, and constraints provided by inclusion of bio-optical models of the water-leaving radiance. References [1]. D. J. Diner, et al. Atmos. Meas. Tech. 6, 1717 (2013). [2]. F. Xu et al. Opt. Lett. 36, 2083 (2011). [3]. J. E. Hansen and L.D. Travis. Space Sci. Rev. 16, 527 (1974). [4]. O. Dubovik et al. Atmos. Meas. Tech., 4, 975 (2011). [5]. O. Dubovik et al. SPIE: Newsroom, DOI:10.1117/2.1201408.005558 (2014).

  10. Simple convergent-nozzle aerosol injector for single-particle diffractive imaging with X-ray free-electron lasers.

    PubMed

    Kirian, R A; Awel, S; Eckerskorn, N; Fleckenstein, H; Wiedorn, M; Adriano, L; Bajt, S; Barthelmess, M; Bean, R; Beyerlein, K R; Chavas, L M G; Domaracky, M; Heymann, M; Horke, D A; Knoska, J; Metz, M; Morgan, A; Oberthuer, D; Roth, N; Sato, T; Xavier, P L; Yefanov, O; Rode, A V; Küpper, J; Chapman, H N

    2015-07-01

    A major challenge in high-resolution x-ray free-electron laser-based coherent diffractive imaging is the development of aerosol injectors that can efficiently deliver particles to the peak intensity of the focused X-ray beam. Here, we consider the use of a simple convergent-orifice nozzle for producing tightly focused beams of particles. Through optical imaging we show that 0.5 μm particles can be focused to a full-width at half maximum diameter of 4.2 μm, and we demonstrate the use of such a nozzle for injecting viruses into a micro-focused soft-X-ray FEL beam. PMID:26798816

  11. Nanoscale Images of Airborne PM2.5: Aerosol Dynamics with the LCLS X-ray Laser

    NASA Astrophysics Data System (ADS)

    Bogan, M. J.

    2012-12-01

    It is now possible to capture images of individual airborne PM2.5 particles - including soot, NaCl particles and engineered nanoparticles - with 20-40 nm resolution (Loh et al Nature 2012). Ions released during the imaging process provide information on the chemical content of the isolated particles. The scattering signal used to compose the image also provides the fractal dimension of individual particles. This new paradigm of aerosol dynamics is enabled by the incredible brightness and ultrashort pulses available at X-ray free electron laser (FEL) facilities, such as the Linac Coherent Light Source (LCLS) and the FLASH FEL facility in Hamburg. Femtosecond long x-ray pulses deliver sufficient photons (10^12 per pulse) to detect scattered X-rays off individual particles injected at >100 m/s into vacuum through an aerodynamic lens stack. The intensity of the scattered X-rays measured by an area detector is fed into lensless imaging algorithms to reconstruct an image of the particle that caused the scattering. X-ray FELs can peer inside the individual airborne particles and are a sensitive probe of particle crystallinity. The development of this method and applications to imaging micron-sized soot, water droplets and biological aerosols will be discussed. A primary long-term goal of the research is to take snapshots of airborne particles as they change their size, shape and chemical make-up in response to their environment. "Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight" ND Loh, C Hampton, A Martin, D Starodub, R Sierra, A Barty, A Aquila, J Schulz, L Lomb, J Steinbrener, R Shoeman, S Kassemeyer, C Bostedt, J. Bozek, S Epp, B. Erk, R Hartmann, D Rolles, A Rudenko, B Rudek, L Foucar, N Kimmel, G Weidenspointner, G Hauser, P Holl, E. Pedersoli, M Liang, M Hunter, L Gumprecht, N Coppola, C Wunderer, H Graafsma, F Maia, T Ekeberg, M Hantke, H Fleckenstein, H. Hirsemann, K Nass, T White, H Tobias, G Farquar, W Benner, S Hau

  12. Coordinated Oxygen Isotopic and Petrologic Studies of CAIS Record Varying Composition of Protosolar

    NASA Technical Reports Server (NTRS)

    Simon, Justin I.; Matzel, J. E. P.; Simon, S. B.; Weber, P. K.; Grossman, L.; Ross, D. K.; Hutcheon, I. D.

    2012-01-01

    Ca-, Al-rich inclusions (CAIs) record the O-isotope composition of Solar nebular gas from which they grew [1]. High spatial resolution O-isotope measurements afforded by ion microprobe analysis across the rims and margin of CAIs reveal systematic variations in (Delta)O-17 and suggest formation from a diversity of nebular environments [2-4]. This heterogeneity has been explained by isotopic mixing between the O-16-rich Solar reservoir [6] and a second O-16-poor reservoir (probably nebular gas) with a "planetary-like" isotopic composition [e.g., 1, 6-7], but the mechanism and location(s) where these events occur within the protoplanetary disk remain uncertain. The orientation of large and systematic variations in (Delta)O-17 reported by [3] for a compact Type A CAI from the Efremovka reduced CV3 chondrite differs dramatically from reports by [4] of a similar CAI, A37 from the Allende oxidized CV3 chondrite. Both studies conclude that CAIs were exposed to distinct, nebular O-isotope reservoirs, implying the transfer of CAIs among different settings within the protoplanetary disk [4]. To test this hypothesis further and the extent of intra-CAI O-isotopic variation, a pristine compact Type A CAI, Ef-1 from Efremovka, and a Type B2 CAI, TS4 from Allende were studied. Our new results are equally intriguing because, collectively, O-isotopic zoning patterns in the CAIs indicate a progressive and cyclic record. The results imply that CAIs were commonly exposed to multiple environments of distinct gas during their formation. Numerical models help constrain conditions and duration of these events.

  13. Aerosol MTF revisited

    NASA Astrophysics Data System (ADS)

    Kopeika, Norman S.; Zilberman, Arkadi; Yitzhaky, Yitzhak

    2014-05-01

    Different views of the significance of aerosol MTF have been reported. For example, one recent paper [OE, 52(4)/2013, pp. 046201] claims that the aerosol MTF "contrast reduction is approximately independent of spatial frequency, and image blur is practically negligible". On the other hand, another recent paper [JOSA A, 11/2013, pp. 2244-2252] claims that aerosols "can have a non-negligible effect on the atmospheric point spread function". We present clear experimental evidence of common significant aerosol blur and evidence that aerosol contrast reduction can be extremely significant. In the IR, it is more appropriate to refer to such phenomena as aerosol-absorption MTF. The role of imaging system instrumentation on such MTF is addressed too.

  14. The Vibrio cholerae quorum-sensing autoinducer CAI-1: analysis of the biosynthetic enzyme CqsA

    SciTech Connect

    Kelly, R.; Bolitho, M; Higgins, D; Lu, W; Ng, W; Jeffrey, P; Rabinowitz, J; Semmelhack, M; Hughson, F; Bassler, B

    2009-01-01

    Vibrio cholerae, the bacterium that causes the disease cholera, controls virulence factor production and biofilm development in response to two extracellular quorum-sensing molecules, called autoinducers. The strongest autoinducer, called CAI-1 (for cholera autoinducer-1), was previously identified as (S)-3-hydroxytridecan-4-one. Biosynthesis of CAI-1 requires the enzyme CqsA. Here, we determine the CqsA reaction mechanism, identify the CqsA substrates as (S)-2-aminobutyrate and decanoyl coenzyme A, and demonstrate that the product of the reaction is 3-aminotridecan-4-one, dubbed amino-CAI-1. CqsA produces amino-CAI-1 by a pyridoxal phosphate-dependent acyl-CoA transferase reaction. Amino-CAI-1 is converted to CAI-1 in a subsequent step via a CqsA-independent mechanism. Consistent with this, we find cells release {ge}100 times more CAI-1 than amino-CAI-1. Nonetheless, V. cholerae responds to amino-CAI-1 as well as CAI-1, whereas other CAI-1 variants do not elicit a quorum-sensing response. Thus, both CAI-1 and amino-CAI-1 have potential as lead molecules in the development of an anticholera treatment.

  15. Remote sensing of cloud, aerosol, and water vapor properties from the moderate resolution imaging spectrometer (MODIS)

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Kaufman, Yoram J.; Menzel, W. Paul; Tanre, Didier D.

    1992-01-01

    The authors describe the status of MODIS-N and its companion instrument MODIS-T (tilt), a tiltable cross-track scanning spectrometer with 32 uniformly spaced channels between 0.410 and 0.875 micron. They review the various methods being developed for the remote sensing of atmospheric properties using MODIS, placing primary emphasis on the principal atmospheric applications of determining the optical, microphysical, and physical properties of clouds and aerosol particles from spectral reflection and thermal emission measurements. In addition to cloud and aerosol properties, MODIS-N will be used for determining the total precipitable water vapor and atmospheric stability. The physical principles behind the determination of each of these atmospheric products are described, together with an example of their application to aircraft and/or satellite measurements.

  16. Audio-Tutorial and CAI Aids for Problem Solving in Introductory Chemistry

    ERIC Educational Resources Information Center

    Lower, Stephen K.

    1970-01-01

    Starting from a successful audio-tutorial program, the author initiated a computer assisted tutorial program in solving chemistry problems. Discusses the advantages of computer assisted instruction (CAI) over audiotapes and the advantages of both over conventional instructional methods. Presents a flow chart of a CAI program on a calorimetry…

  17. Knowledge-Based CAI: CINS for Individualized Curriculum Sequencing. Final Technical Report No. 290.

    ERIC Educational Resources Information Center

    Wescourt, Keith T.; And Others

    This report describes research on the Curriculum Information Network (CIN) paradigm for computer-assisted instruction (CAI) in technical subjects. The CIN concept was first conceived and implemented in the BASIC Instructional Program (BIP). The primary objective of CIN-based CAI and the BIP project has been to develop procedures for providing each…

  18. The Computer as a Socializing Agent: Some Socioaffective Outcomes of CAI.

    ERIC Educational Resources Information Center

    Hess, Robert D.; And Others

    The socializing role of computer-assisted instruction (CAI) was seen to be a positive one in this study. The students, predominantly Mexican-American, who experienced CAI, and other students, in a control group, who did not, liked the computer. They thought it gave the right answers and they respected it as having a vast array of information…

  19. A Study of Effectiveness of Computer Assisted Instruction (CAI) over Classroom Lecture (CRL) at ICS Level

    ERIC Educational Resources Information Center

    Kaousar, Tayyeba; Choudhry, Bushra Naoreen; Gujjar, Aijaz Ahmed

    2008-01-01

    This study was aimed to evaluate the effectiveness of CAI vs. classroom lecture for computer science at ICS level. The objectives were to compare the learning effects of two groups with classroom lecture and computer-assisted instruction studying the same curriculum and the effects of CAI and CRL in terms of cognitive development. Hypotheses of…

  20. The Graphics Terminal Display System; a Powerful General-Purpose CAI Package.

    ERIC Educational Resources Information Center

    Hornbeck, Frederick W., Brock, Lynn

    The Graphic Terminal Display System (GTDS) was created to support research and development in computer-assisted instruction (CAI). The system uses an IBM 360/50 computer and interfaces with a large-screen graphics display terminal, a random-access slide projector, and a speech synthesizer. An authoring language, GRAIL, was developed for CAI, and…

  1. Effects of Computer Assisted Instruction (CAI) on Secondary School Students' Performance in Biology

    ERIC Educational Resources Information Center

    Yusuf, Mudasiru Olalere; Afolabi, Adedeji Olufemi

    2010-01-01

    This study investigated the effects of computer assisted instruction (CAI) on secondary school students' performance in biology. Also, the influence of gender on the performance of students exposed to CAI in individualised or cooperative learning settings package was examined. The research was a quasi experimental involving a 3 x 2 factorial…

  2. Curricular and Computer System Compatibility of CAI Programs for Multi-University Use.

    ERIC Educational Resources Information Center

    Hall, Keith A.

    A brief introduction to developmental efforts in computer assisted instruction (CAI) at Pennsylvania State University is followed by a description of a program of mobile CAI facilities inaugurated in 1970 as part of the inservice continuing education program for teachers. The paper includes very brief descriptions of the graduate level courses…

  3. Distribution of vanadium and melting of opaque assemblages in Efremovka CAI's

    NASA Technical Reports Server (NTRS)

    Casanova, I.; Grossman, L.

    1993-01-01

    A petrographic and chemical study of compact Type A CAI's from the Efremovka CV3 chondrite strongly suggests that the opaque assemblages (OA's) that they contain were molten at temperatures below the CAI silicate solidus, and that the V-rich magnetite presently observed in association with OA's formed by in situ oxidation of their FeNi.

  4. Generative Computer Assisted Instruction: An Application of Artificial Intelligence to CAI.

    ERIC Educational Resources Information Center

    Koffman, Elliot B.

    Frame-oriented computer-assisted instruction (CAI) systems dominate the field, but these mechanized programed texts utilize the computational power of the computer to a minimal degree and are difficult to modify. Newer, generative CAI systems which are supplied with a knowledge of subject matter can generate their own problems and solutions, can…

  5. An Object-Oriented Architecture for a Web-Based CAI System.

    ERIC Educational Resources Information Center

    Nakabayashi, Kiyoshi; Hoshide, Takahide; Seshimo, Hitoshi; Fukuhara, Yoshimi

    This paper describes the design and implementation of an object-oriented World Wide Web-based CAI (Computer-Assisted Instruction) system. The goal of the design is to provide a flexible CAI/ITS (Intelligent Tutoring System) framework with full extendibility and reusability, as well as to exploit Web-based software technologies such as JAVA, ASP (a…

  6. Petrological Investigations of CAIs from Efremovka and NWA 3118 CV3 Chondrites

    NASA Astrophysics Data System (ADS)

    Ivanova, M. A.; Lorenz, C. A.; Korochantseva, E. V.; MacPherson, G. J.

    2010-03-01

    Several new big CAIs were extracted from the Efremovka and NWA 3118 CV3 chondrites to analyze petrology, chemistry and isotopic compositions. Here we report preliminary results on mineralogy, petrology and bulk chemistry of two CAIs, of Type B1 and of Type A.

  7. A Multi-Media CAI Terminal Based upon a Microprocessor with Applications for the Handicapped.

    ERIC Educational Resources Information Center

    Brebner, Ann; Hallworth, H. J.

    The design of the CAI interface described is based on the microprocessor in order to meet three basic requirements for providing appropriate instruction to the developmentally handicapped: (1) portability, so that CAI can be taken into the customary learning environment; (2) reliability; and (3) flexibility, to permit use of new input and output…

  8. A Position Paper on CAI Research and Development. A Series Two Paper from ERIC at Stanford.

    ERIC Educational Resources Information Center

    Feldhusen, John H.; Lorton, Paul, Jr.

    After a critical review of the papers on Computer-Assisted Instruction (CAI) of several prominent educators, recommendations are proffered for CAI systems improvements prior to new research. These include replacing the typed message with an inexpensive cathode ray tube, developing the student interface as an efficient and pleasant carrel which…

  9. Computer-Aided Technical Training Using Electronic Equipment On-Line with the CAI System.

    ERIC Educational Resources Information Center

    Huggett, Geoffrey; And Others

    This report describes an experimental course in the operation and troubleshooting of a communications transceiver, the AN/URC-32, in which the transceiver is used as part of an instructional station in a CAI system. The transceiver and the CAI system are hard-wired together to form a single training system. The system is presently operating in the…

  10. Nebular History of the Allende FoB CAI SJ101

    NASA Astrophysics Data System (ADS)

    Petaev, M. I.; Jacobsen, S. B.

    2009-03-01

    We compare petrologic and chemical characteristics of a unique FoB CAI SJ101 with the results of thermodynamic modeling of condensation of its precursors in a system of solar composition and speculate about nebular formation history of this CAI.

  11. Passive multiangle imaging of clouds, aerosols, and atmospheric dynamics: Broadening our vision from MISR to WindCam and MSPI

    NASA Astrophysics Data System (ADS)

    Diner, D. J.; Wu, D. L.; Chipman, R.; Davis, A.; Misr Science Team

    2010-12-01

    The Multi-angle Imaging SpectroRadiometer (MISR) has been collecting global Earth data from NASA’s Terra satellite since February 2000. With its nine along-track view angles, four visible/near-infrared spectral bands, intrinsic spatial resolution of 275 m, and stable calibration, no instrument that combines MISR’s attributes has previously flown in space, nor is there is a similar capability currently available on any other satellite platform. The MISR data record provides unprecedented opportunities for characterizing long-term variability in aerosol and cloud structure and atmospheric dynamics, including measurements of the vertical distributions of clouds; aerosol (smoke, volcanic, and dust) plume heights and global optical depths and particle properties; and pole-to-pole height-resolved winds. To extend what has been learned during the first decade of MISR observations, we are developing the WindCam and Multiangle SpectroPolarimetric Imager (MSPI) instruments. WindCam will enable MISR-like stereo observations over a broader swath using a much more compact sensor design. MSPI expands MISR capabilities through broader spectral coverage (ultraviolet to shortwave infrared), wider swath (enabling more rapid global coverage), and incorporation of high-accuracy polarimetric imaging, which will provide greater sensitivity to particle microphysics. A ground-based prototype camera (GroundMSPI) with spectral coverage from 355-935 nm has been built and an airborne version (AirMSPI) is ready for flight on NASA’s ER-2 high-altitude aircraft. Algorithm developments and improvements enabled by increases in computational speed since Terra launch are being explored with MISR data, and will be needed to handle the rich information content of these MISR successor instruments.

  12. INAA of CAIs from the Maralinga CK4 chondrite: Effects of parent body thermal metamorphism

    NASA Technical Reports Server (NTRS)

    Lindstrom, D. J.; Keller, L. P.; Martinez, R. R.

    1993-01-01

    Maralinga is an anomalous CK4 carbonaceous chondrite which contains numerous Ca-, Al-rich inclusions (CAI's) unlike the other members of the CK group. These CAI's are characterized by abundant green hercynitic spinel intergrown with plagioclase and high-Ca clinopyroxene, and a total lack of melilite. Instrumental Neutron Activation Analysis (INAA) was used to further characterize the meteorite, with special focus on the CAI's. High sensitivity INAA was done on eight sample disks about 100-150 microns in diameter obtained from a normal 30 micron thin section with a diamond microcoring device. The CAI's are enriched by 60-70X bulk meteorite values in Zn, suggesting that the substantial exchange of Fe for Mg that made the spinel in the CAI's hercynitic also allowed efficient scavenging of Zn from the rest of the meteorite during parent body thermal metamorphism. Less mobile elements appear to have maintained their initial heterogeneity.

  13. First retrieval of data regarding spatial distribution of Asian dust aerosol from the Geostationary Ocean Color Imager

    NASA Astrophysics Data System (ADS)

    Lee, Kwon Ho; Ryu, Joo Hyung; Ahn, Jae Hyun; Kim, Young Joon

    2012-12-01

    Aerosol optical thickness (AOT) was retrieved from the Geostationary Ocean Color Imager (GOCI) on board the Communication, Ocean, and Meteorological Satellite (COMS) for the first time. AOT values were retrieved over the ocean at a spatial scale of 0.5 × 0.5 km2 by using the look-up table (LUT)-based separation technique. The radiative transfer model (RTM) was used for different models of atmosphere-ocean environmental conditions, taking into account the realistic variability of scattering and absorption. Ocean surface properties affected by whitecaps and pigment content were also taken into account. The results show that the radiance observed by the GOCI amounts to only 5% of the radiation that penetrated the ocean and, consequently, 95% of the radiation is scattered in the atmosphere or reflected at the ocean surface in the visible wavelengths longer than 0.6 ìm. Within these wavelengths, radiance variations at the top of atmosphere (TOA) due to pigment variations are within 10%, while the radiance variation due to wind speed is considerably higher. For verification of GOCI-retrieved AOTs, comparison between GOCI and ground-based sunphotometer measurement at Gosan, Korea (126.10°E, 33.23°N)) showed good correlation (r = 0.99). The GOCI observations obtained by using the proposed technique showed promising results for the daily monitoring of atmospheric aerosol loading as well as being useful for environmental supervisory authorities.

  14. CFD Modeling and Image Analysis of Exhaled Aerosols due to a Growing Bronchial Tumor: towards Non-Invasive Diagnosis and Treatment of Respiratory Obstructive Diseases

    PubMed Central

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol. PMID:25767612

  15. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: towards non-invasive diagnosis and treatment of respiratory obstructive diseases.

    PubMed

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A; Corley, Richard A; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.

  16. CFD Modeling and Image Analysis of Exhaled Aerosols due to a Growing Bronchial Tumor: towards Non-Invasive Diagnosis and Treatment of Respiratory Obstructive Diseases

    SciTech Connect

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-02-06

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure vari-ations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagran-gian tracking approach were used to model respiratory airflows and aerosol dynamics. Respira-tions of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug de-livery protocol.

  17. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: Towards non-invasive diagnosis and treatment of respiratory obstructive diseases

    SciTech Connect

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 μm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.

  18. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: Towards non-invasive diagnosis and treatment of respiratory obstructive diseases

    DOE PAGES

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-01-01

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treatmore » the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 μm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol.« less

  19. Chemical imaging of ambient aerosol particles: Observational constraints on mixing state parameterization

    NASA Astrophysics Data System (ADS)

    O'Brien, Rachel E.; Wang, Bingbing; Laskin, Alexander; Riemer, Nicole; West, Matthew; Zhang, Qi; Sun, Yele; Yu, Xiao-Ying; Alpert, Peter; Knopf, Daniel A.; Gilles, Mary K.; Moffet, Ryan C.

    2015-09-01

    A new parameterization for quantifying the mixing state of aerosol populations has been applied for the first time to samples of ambient particles analyzed using spectro-microscopy techniques. Scanning transmission X-ray microscopy/near edge X-ray absorption fine structure (STXM/NEXAFS) and computer-controlled scanning electron microscopy/energy dispersive X-ray spectroscopy (CCSEM/EDX) were used to probe the composition of the organic and inorganic fraction of individual particles collected on 27 and 28 June during the 2010 Carbonaceous Aerosols and Radiative Effects study in the Central Valley, California. The first field site, T0, was located in downtown Sacramento, while T1 was located near the Sierra Nevada Mountains. Mass estimates of the aerosol particle components were used to calculate mixing state metrics, such as the particle-specific diversity, bulk population diversity, and mixing state index, for each sample. The STXM data showed evidence of changes in the mixing state associated with a buildup of organic matter confirmed by collocated measurements, and the largest impact on the mixing state was due to an increase in soot dominant particles during this buildup. The mixing state from STXM was similar between T0 and T1, indicating that the increased organic fraction at T1 had a small effect on the mixing state of the population. The CCSEM/EDX analysis showed the presence of two types of particle populations: the first was dominated by aged sea-salt particles and had a higher mixing state index (indicating a more homogeneous population); the second was dominated by carbonaceous particles and had a lower mixing state index.

  20. Aerosol optical properties derived from the DRAGON-NE Asia campaign, and implications for a single-channel algorithm to retrieve aerosol optical depth in spring from Meteorological Imager (MI) on-board the Communication, Ocean, and Meteorological Satellite (COMS)

    NASA Astrophysics Data System (ADS)

    Kim, M.; Kim, J.; Jeong, U.; Kim, W.; Hong, H.; Holben, B.; Eck, T. F.; Lim, J. H.; Song, C. K.; Lee, S.; Chung, C.-Y.

    2016-02-01

    An aerosol model optimized for northeast Asia is updated with the inversion data from the Distributed Regional Aerosol Gridded Observation Networks (DRAGON)-northeast (NE) Asia campaign which was conducted during spring from March to May 2012. This updated aerosol model was then applied to a single visible channel algorithm to retrieve aerosol optical depth (AOD) from a Meteorological Imager (MI) on-board the geostationary meteorological satellite, Communication, Ocean, and Meteorological Satellite (COMS). This model plays an important role in retrieving accurate AOD from a single visible channel measurement. For the single-channel retrieval, sensitivity tests showed that perturbations by 4 % (0.926 ± 0.04) in the assumed single scattering albedo (SSA) can result in the retrieval error in AOD by over 20 %. Since the measured reflectance at the top of the atmosphere depends on both AOD and SSA, the overestimation of assumed SSA in the aerosol model leads to an underestimation of AOD. Based on the AErosol RObotic NETwork (AERONET) inversion data sets obtained over East Asia before 2011, seasonally analyzed aerosol optical properties (AOPs) were categorized by SSAs at 675 nm of 0.92 ± 0.035 for spring (March, April, and May). After the DRAGON-NE Asia campaign in 2012, the SSA during spring showed a slight increase to 0.93 ± 0.035. In terms of the volume size distribution, the mode radius of coarse particles was increased from 2.08 ± 0.40 to 2.14 ± 0.40. While the original aerosol model consists of volume size distribution and refractive indices obtained before 2011, the new model is constructed by using a total data set after the DRAGON-NE Asia campaign. The large volume of data in high spatial resolution from this intensive campaign can be used to improve the representative aerosol model for East Asia. Accordingly, the new AOD data sets retrieved from a single-channel algorithm, which uses a precalculated look-up table (LUT) with the new aerosol model, show an

  1. A Novel Method to Retrieve Aerosol Optical Thickness from High-Resolution Optical Satellite Images for Air Quality Monitoring

    NASA Astrophysics Data System (ADS)

    Nield, J. M.; Wilson, R. T.; Milton, E. J.

    2015-12-01

    Aerosol Optical Thickness (AOT) data has many important applications including atmospheric correction of satellite imagery and monitoring of particulate matter air pollution. Current data products are generally available at a kilometre-scale resolution, but many applications require far higher resolutions. For example, particulate matter concentrations vary on a metre-scale, and thus data products at a similar scale are required to provide accurate assessments of particle densities and allow effective monitoring of air quality and analysis of local air quality effects on health. A novel method has been developed which retrieves per-pixel AOT values from high-resolution (~30m) satellite data. This method is designed to work over a wide range of land covers - including both bright and dark surfaces - and requires only standard visible and near-infrared data, making it applicable to a range of data from sensors such as Landsat, SPOT and Sentinel-2. The method is based upon an extension of the Haze Optimized Transform (HOT). The HOT was originally designed for assessing areas of thick haze in satellite imagery by calculating a 'haziness' value for each pixel in an image as the distance from a 'Clear Line' in feature space, defined by the high correlation between visible bands. Here, we adapt the HOT method and use it to provide AOT data instead. Significant extensions include Monte Carlo estimation of the 'Clear Line', object-based correction for land cover, and estimation of AOT from the haziness values through radiative transfer modelling. This novel method will enable many new applications of AOT data that were impossible with previously available low-resolution data, and has the potential to contribute significantly to our understanding of the air quality on health, the accuracy of satellite image atmospheric correction and the role of aerosols in the climate system.

  2. Cloud Retrieval Information Content Studies with the Pre-Aerosol, Cloud and ocean Ecosystem (PACE) Ocean Color Imager (OCI)

    NASA Astrophysics Data System (ADS)

    Coddington, Odele; Platnick, Steven; Pilewskie, Peter; Schmidt, Sebastian

    2016-04-01

    The NASA Pre-Aerosol, Cloud and ocean Ecosystem (PACE) Science Definition Team (SDT) report released in 2012 defined imager stability requirements for the Ocean Color Instrument (OCI) at the sub-percent level. While the instrument suite and measurement requirements are currently being determined, the PACE SDT report provided details on imager options and spectral specifications. The options for a threshold instrument included a hyperspectral imager from 350-800 nm, two near-infrared (NIR) channels, and three short wave infrared (SWIR) channels at 1240, 1640, and 2130 nm. Other instrument options include a variation of the threshold instrument with 3 additional spectral channels at 940, 1378, and 2250 nm and the inclusion of a spectral polarimeter. In this work, we present cloud retrieval information content studies of optical thickness, droplet effective radius, and thermodynamic phase to quantify the potential for continuing the low cloud climate data record established by the MOderate Resolution and Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) missions with the PACE OCI instrument (i.e., non-polarized cloud reflectances and in the absence of midwave and longwave infrared channels). The information content analysis is performed using the GEneralized Nonlinear Retrieval Analysis (GENRA) methodology and the Collection 6 simulated cloud reflectance data for the common MODIS/VIIRS algorithm (MODAWG) for Cloud Mask, Cloud-Top, and Optical Properties. We show that using both channels near 2 microns improves the probability of cloud phase discrimination with shortwave-only cloud reflectance retrievals. Ongoing work will extend the information content analysis, currently performed for dark ocean surfaces, to different land surface types.

  3. Effects of Computer-assisted Instruction (CAI) on 11th Graders' Attitudes to Biology and CAI and Understanding of Reproduction in Plants and Animals

    NASA Astrophysics Data System (ADS)

    Soyibo, Kola; Hudson, Ann

    2000-02-01

    This study investigated whether the use of the combination of the lecture, discussion and computer-assisted instruction (CAI) significantly improved the experimental students' attitudes to biology and the computer/CAI and their understanding of reproduction in plants and animals. The sample comprised 77 Jamaican grade 11 female students from two traditional high schools in Kingston. Attitudes to a biology questionnaire, attitudes to the computer/CAI questionnaire and a biology achievement test (BAT) were used for data collection. The results indicated that the experimental subjects' post-test attitudes to biology and the computer/CAI were significantly better than those of the control group subjects taught with the lecture and discussion methods; the experimental subjects significantly outscored the control group subjects on the post-test BAT; there were significant differences in their post-test BAT means based on their attitudes to biology in favour of experimental subjects with highly favourable attitudes to biology, but there were no significant differences in their means attributable to their post-test attitudes to the computer/CAI; there was a positive statistically significant but weak relationship between the experimental subjects' post-test attitudes to biology and their post-test BAT scores.

  4. Microstructural Investigation of a Wark-Lovering Rim on a Vigarano CAI

    NASA Technical Reports Server (NTRS)

    Han, J.; Keller, L. P.; Needham, A. W.; Messenger, S.; Simon, J. I.

    2015-01-01

    Wark-Lovering (WL) rims are thin multi-layered mineral sequences that surround many CAIs. These rim layers consist of the primary minerals found in the CAI interiors, but vary in their mineralogy. Several models for their origin have been proposed including condensation, reaction with a nebular gas, evaporation, or combinations of these. However, there still is little consensus on how and when the rims formed. Here, we describe the microstructure and mineralogy of a WL rim on a type B CAI from the Vigarano CV(sub red) chondrite using FIB/TEM to better understand the astrophysical significance of WL rim formation.

  5. Pushing back the limits of Raman imaging by coupling super-resolution and chemometrics for aerosols characterization

    PubMed Central

    Offroy, Marc; Moreau, Myriam; Sobanska, Sophie; Milanfar, Peyman; Duponchel, Ludovic

    2015-01-01

    The increasing interest in nanoscience in many research fields like physics, chemistry, and biology, including the environmental fate of the produced nano-objects, requires instrumental improvements to address the sub-micrometric analysis challenges. The originality of our approach is to use both the super-resolution concept and multivariate curve resolution (MCR-ALS) algorithm in confocal Raman imaging to surmount its instrumental limits and to characterize chemical components of atmospheric aerosols at the level of the individual particles. We demonstrate the possibility to go beyond the diffraction limit with this algorithmic approach. Indeed, the spatial resolution is improved by 65% to achieve 200 nm for the considered far-field spectrophotometer. A multivariate curve resolution method is then coupled with super-resolution in order to explore the heterogeneous structure of submicron particles for describing physical and chemical processes that may occur in the atmosphere. The proposed methodology provides new tools for sub-micron characterization of heterogeneous samples using far-field (i.e. conventional) Raman imaging spectrometer. PMID:26201867

  6. Pushing back the limits of Raman imaging by coupling super-resolution and chemometrics for aerosols characterization

    NASA Astrophysics Data System (ADS)

    Offroy, Marc; Moreau, Myriam; Sobanska, Sophie; Milanfar, Peyman; Duponchel, Ludovic

    2015-07-01

    The increasing interest in nanoscience in many research fields like physics, chemistry, and biology, including the environmental fate of the produced nano-objects, requires instrumental improvements to address the sub-micrometric analysis challenges. The originality of our approach is to use both the super-resolution concept and multivariate curve resolution (MCR-ALS) algorithm in confocal Raman imaging to surmount its instrumental limits and to characterize chemical components of atmospheric aerosols at the level of the individual particles. We demonstrate the possibility to go beyond the diffraction limit with this algorithmic approach. Indeed, the spatial resolution is improved by 65% to achieve 200 nm for the considered far-field spectrophotometer. A multivariate curve resolution method is then coupled with super-resolution in order to explore the heterogeneous structure of submicron particles for describing physical and chemical processes that may occur in the atmosphere. The proposed methodology provides new tools for sub-micron characterization of heterogeneous samples using far-field (i.e. conventional) Raman imaging spectrometer.

  7. Image-Processing Educator

    NASA Technical Reports Server (NTRS)

    Gunther, F. J.

    1986-01-01

    Apple Image-Processing Educator (AIPE) explores ability of microcomputers to provide personalized computer-assisted instruction (CAI) in digital image processing of remotely sensed images. AIPE is "proof-of-concept" system, not polished production system. User-friendly prompts provide access to explanations of common features of digital image processing and of sample programs that implement these features.

  8. Formation of refractory metal nuggets and their link to the history of CAIs

    NASA Astrophysics Data System (ADS)

    Schwander, D.; Kööp, L.; Berg, T.; Schönhense, G.; Heck, P. R.; Davis, A. M.; Ott, U.

    2015-11-01

    Ca, Al-rich inclusions (CAIs) often contain numerous refractory metal nuggets (RMNs), consisting of elements like Os, Ir, Mo, Pt and Ru. The nuggets are usually thought to have formed by equilibrium condensation from a gas of solar composition, simultaneously with or prior to oxide and silicate minerals. However, the exact mechanisms responsible for their extremely variable compositions, small sizes and associations with CAI minerals remain puzzling. Expanding on previous work on chemically separated RMNs, we have studied a large number of RMNs within their host CAIs from three different meteorite types, i.e., the highly primitive chondrite Acfer 094 (C2-ungrouped), Allende (CV3ox) and Murchison (CM2). Our results show several inconsistencies between the observed features and a direct condensation origin, including a lack of correlated abundance variations in the refractory metals that are expected from variations in condensation temperature. Instead, we show that most RMN features are consistent with RMN formation by precipitation from a CAI liquid enriched in refractory metals. This scenario is additionally supported by the common occurrence of RMNs in CAIs with clear melt crystallization textures as well as the occurrence of synthetic RMNs with highly variable compositions in run products from Schwander et al. (2015). In some cases, the sizes of meteoritic RMNs correlate with the sizes of their host minerals in CAIs, which indicates common cooling rates.

  9. Effects of Computer-Assisted Instruction (CAI) on 11th Graders' Attitudes to Biology and CAI and Understanding of Reproduction in Plants and Animals.

    ERIC Educational Resources Information Center

    Soyibo, Kola; Hudson, Ann

    2000-01-01

    Investigates whether the use of the combination of lecture, discussion, and computer-assisted instruction (CAI) significantly improved students' attitudes toward biology and their understanding of reproduction in plants and animals. Studies grade 11 Jamaican female students (n=77) from two traditional high schools in Kingston. (Contains 19…

  10. The effect of forced expiration on the uniformity of 99Tcm-DTPA aerosol ventilation images in patients with excess sputum production.

    PubMed

    Middleton, E; Clout, C; Occleshaw, C; Tindale, W B; Parker, B V; Barber, D C; Barrington, N A

    1990-08-01

    This study examines the use of the forced expiratory technique (FET) as a means of improving the uniformity of radionuclide aerosol ventilation images in patients with excess sputum production. Ventilation images are objectively classified by two computer derived indices to characterize the degree of radioaerosol clumping and overall uniformity. In a series of twenty five patients with a long-standing history of daily sputum production, images acquired before and after forced expiration and again after a second ventilation immediately following FET showed no significant change in either index. The results obtained do not provide evidence to support the routine use of FET in conjunction with radioaerosol scintigraphy. The method of image classification correlates well with a visual assessment of image uniformity and has general application.

  11. Search for extinct 36Cl: Vigarano CAIs, the Pink Angel from Allende, and a Ningqiang chondrule

    NASA Astrophysics Data System (ADS)

    Nakashima, Daisuke; Ott, Ulrich; Hoppe, Peter; El Goresy, Ahmed

    2008-12-01

    We have searched for excesses of 36S derived from the decay of extinct 36Cl in sodalite, a secondary Cl-rich mineral, in Ca-Al-rich inclusions (CAIs) from the Vigarano and Allende CV3 chondrites and in a chondrule from the Ningqiang carbonaceous chondrite. The presence of sodalite in two CAIs from Vigarano and its absence from surrounding CAI fragments suggests sodalite formation after CAI fragmentation. As for sodalite in the Allende Pink Angel CAI, oxygen isotopic compositions have been interpreted as indicative of high temperature interactions, thus suggesting formation prior to accretion to the parent body, probably in a nebular setting. Sodalite in the Ningqiang chondrule is considered to have formed via alkali-Ca exchange, which is believed to have occurred before accretion to the parent body. Sodalites in the Vigarano CAIs and in the Ningqiang chondrule show no clear evidence for the presence of radiogenic 36S. The inferred 2 σ upper limits for 36Cl/ 35Cl at the time of sodalite formation are 1.6 × 10 -6 (Vigarano CAIs) and 3.3 × 10 -6 (Ningqiang chondrule), respectively. In the Pink Angel CAI sodalite exhibits small 36S excesses which weakly correlate with 35Cl/ 34S ratios. The inferred 36Cl/ 35Cl ratio of (1.8 ± 2.2) × 10 -6 (2 σ error) is lower than that found by Hsu et al. [Hsu, W., Guan, Y., Leshin, L. A., Ushikubo, T. and Wasserburg, G. J. (2006) A late episode of irradiation in the early solar system: Evidence from extinct 36Cl and 26Al in meteorites. Astrophys. J. 640, 525-529], thus indicative of heterogeneous distribution of 36Cl in this CAI. Spallation reactions induced by energetic particles from the young Sun are suggested for the origin of 36Cl, similar to the case of 10Be. While 10Be appears to be present in roughly equal abundance in all studied CAIs, our study indicates the level of 36Cl abundances to be variable so that there seems to be no simple relationship between 10Be and 36Cl. This would be expected if trapped cosmic rays rather

  12. Evidence for extinct 135Cs from Ba isotopes in Allende CAIs?

    NASA Astrophysics Data System (ADS)

    Bermingham, K. R.; Mezger, K.; Desch, S. J.; Scherer, E. E.; Horstmann, M.

    2014-05-01

    The abundance and distribution of isotopes throughout the Solar System can be used to constrain the number and type of nucleosynthetic events that contributed material to the early nebula. Barium is particularly well suited to quantifying the degree of isotope heterogeneity in the Solar System because it comprises seven stable isotopes that were synthesized by three different nucleosynthetic processes (s-, r-, and p-processes), all of which contributed material to the Solar System. There is also potential contribution to 135Ba from short-lived radioisotope 135Cs, conclusive evidence for which is yet to be reported. Four Allende (CV3) Ca,Al-rich inclusions (CAI 1, CAI 2, CAI 4, CAI 5) and one Allende dark inclusion (DI) were analyzed for Ba isotope variability. Two CAIs (CAI 2 and CAI 5) display 135Ba excesses that are not accompanied by 137Ba anomalies. Calcium-aluminum-rich inclusion 1 displays a 135Ba excess that is possibly coupled with a 137Ba excess, and the remaining refractory inclusions (CAI 2 and DI) have terrestrial Ba isotope compositions. These Ba isotope data are presented in conjunction with published whole rock Ba isotope data from individual Allende CAIs. The enrichment in 135Ba and absence of coupled 137Ba excesses in CAI 2 and CAI 5 is interpreted to indicate that the anomalies are not purely nucleosynthetic in origin but also contain contributions (16-48 ppm) from the decay of short-lived 135Cs. The majority of Allende CAIs studied to date may also have similar contributions from 135Cs on the basis of higher than expected 135Ba excesses if the Ba isotope anomalies were purely nucleosynthetic in origin. The 135Ba anomalies appear not to be coupled with superchondritic Cs/Ba, which may imply that the contribution to 135Ba did not occur via in situ decay of live 135Cs. However, it is feasible that the CAIs had a superchondritic Cs/Ba during decay of 135Cs, but Cs was subsequently removed from the system during aqueous alteration on the parent body

  13. The Formation Of The First Solids In The Solar System: An Investigation Of CAI Diversity

    NASA Astrophysics Data System (ADS)

    Taillifet, Esther; Baillié, K.; Charnoz, S.; Aléon, J.

    2012-10-01

    Chondritic meteorites are primitive bodies and therefore an important source of information on the first moments of planets formation. Chondrites contain several materials especially calcium and aluminum rich inclusions (CAIs), known to be the oldest objects of the solar system (4.567 Gyr - Amelin et al., 2002; Connelly et al., 2008) and thus the first solids to be formed. CAIs appear in various textures, sizes and compositions in chondrites. Though, all of them should have formed at high temperature (1300-1800 K) in the same region of the solar nebula by condensation from the gas (e.g. Grossman, 1972; Yoneda & Grossman, 1995; Petaev & Wood, 1998; Ebel & Grossman 2000). To answer this problem we study the CAI formation within the solar nebula using numerical simulations. For this work we developed a self consistent thermodynamical model of the solar nebula (see associated talk from Baillié et. al ) based on previous works (Calvet et. al, 1991; Hueso & Guillot, 2005; Dullemond, Dominik and Natta, 2001). Using this model, we simulate the young system with Lagrangian Implicit Disk Transport code (LIDT - Charnoz et. al, 2010). We will focus on the very first instants of the CAIs within the few years following their condensation. We will report our first results in terms of thermal history and investigate if turbulence-driven transport may explain the CAI diversity.

  14. The ethnoecology of Caiçara metapopulations (Atlantic Forest, Brazil): ecological concepts and questions

    PubMed Central

    Begossi, Alpina

    2006-01-01

    The Atlantic Forest is represented on the coast of Brazil by approximately 7,5% of remnants, much of these concentrated on the country's SE coast. Within these southeastern remnants, we still find the coastal Caiçaras who descend from Native Indians and Portuguese Colonizers. The maintenance of such populations, and their existence in spite of the deforestation that occurred on the Atlantic Forest coast, deserves especial attention and analysis. In this study, I address, in particular, the Caiçaras who live on the coast of São Paulo and Rio de Janeiro States, illustrating with examples of coastal inhabitants from other areas, such as Bahia State (NE coast) and of other forested areas (riverine caboclos of the Amazon). The major focus of this study, based on previous research, performed since 1986 in several populations or villages of the Atlantic Forest coast, is to understand the resilience of the Caiçaras, which is analyzed using ecological concepts, such as metapopulation, resilience and adaptive cycles. The Caiçara populations are located on islands (Búzios, Comprida, Grande, Ilhabela, Jaguanum, Gipóia) and on the coast (Bertioga, Puruba, Picinguaba, among others). Information gathered about the Caiçaras regarding the economic cycles of the local regions, along with ecological, historical and economic data available, are used to understand such resilience, and are complemented with comparative examples from the Brazilian Amazon and with variables such as the local restrictions imposed by environmental governmental agencies. PMID:17010204

  15. Mineralogy and Petrology of EK-459-5-1, A Type B1 CAI from Allende

    NASA Technical Reports Server (NTRS)

    Jeffcoat, C. R.; Kerekgyarto, A. G.; Lapen, T. J.; Andreasen, R.; Righter, M.; Ross, D. K.

    2015-01-01

    Calcium-aluminum-rich inclusions (CAIs) are a type of coarse-grained clast composed of Ca-, Al-, and Mg-rich silicates and oxides found in chondrite meteorites. Type B (CAIs) are exclusively found in the CV chondrite meteorites and are the most well studied type of inclusion found in chondritic meteorites. Type B1 CAIs are distinguished by a nearly monomineralic rim of melilite that surrounds an interior predominantly composed of melilite, fassaite (Ti and Al-rich clinopyroxene), anorthite, and spinel with varying amounts of other minor primary and secondary phases. The formation of Type B CAIs has received considerable attention in the course of CAI research and quantitative models, experimental results and observations from Type B inclusions remain largely in disagreement. Recent experimental results and quantitative models have shown that the formation of B1 mantles could have occurred by the evaporative loss of Si and Mg during the crystallization of these objects. However, comparative studies suggest that the lower bulk SiO2 compositions in B1s result in more prior melilite crystallization before the onset of fassaite and anorthite crystallization leading to the formation of thick melilite rich rims in B1 inclusions. Detailed petrographic and cosmochemical studies of these inclusions will further our understanding of these complex objects.

  16. Measurements of mesospheric water vapour, aerosols and temperatures with the Spectral Absorption Line Imager (SALI-AT)

    NASA Astrophysics Data System (ADS)

    Shepherd, M. G.; Mullins, M.; Brown, S.; Sargoytchev, S. I.

    2001-08-01

    Water vapour concentration is one of the most important, yet one of the least known quantities of the mesosphere. Knowledge of water vapour concentration is the key to understanding many mesospheric processes, including the one that is primary focus of our investigation, mesospheric clouds (MC). The processes of formation and occurrence parameters of MC constitute an interesting problem in their own right, but recently evidence has been provided which suggests that they are a critical indicator of atmospheric change. The aim of the SALI-AT experiment is to make simultaneous (although not strictly collocated) measurements of water vapour, aerosols and temperature in the mesosphere and the mesopause region under twilight condition in the presence of mesospheric clouds. The water vapour will be measured in the regime of solar occultation utilizing a water vapour absorption band at 936 nm wavelength employing the SALI (Spectral Absorption Line Imager) instrument concept. A three-channel zenith photometer, AT-3, with wavelengths of 385 nm, 525 nm, and 1040 nm will measure Mie and Rayleigh scattering giving both mesospheric temperature profiles and the particle size distribution. Both instruments are small, low cost and low mass. It is envisioned that the SALI-AT experiment be flown on a small rocket - the Improved Orion/Hotel payload configuration, from the Andoya Rocket range, Norway. Alternatively the instrument can be flown as a "passenger" on larger rocket carrying other experiments. In either case flight costs are relatively low. Some performance simulations are presented showing that the instrument we have designed will be sufficiently sensitive to measure water vapor in concentrations that are expected at the summer mesopause, about 85 km height.

  17. Exploring the effects of landscape structure on aerosol optical depth (AOD) patterns using GIS and HJ-1B images.

    PubMed

    Ye, Luping; Fang, Linchuan; Tan, Wenfeng; Wang, Yunqiang; Huang, Yu

    2016-02-01

    A GIS approach and HJ-1B images were employed to determine the effect of landscape structure on aerosol optical depth (AOD) patterns. Landscape metrics, fractal analysis and contribution analysis were proposed to quantitatively illustrate the impact of land use on AOD patterns. The high correlation between the mean AOD and landscape metrics indicates that both the landscape composition and spatial structure affect the AOD pattern. Additionally, the fractal analysis demonstrated that the densities of built-up areas and bare land decreased from the high AOD centers to the outer boundary, but those of water and forest increased. These results reveal that the built-up area is the main positive contributor to air pollution, followed by bare land. Although bare land had a high AOD, it made a limited contribution to regional air pollution due to its small spatial extent. The contribution analysis further elucidated that built-up areas and bare land can increase air pollution more strongly in spring than in autumn, whereas forest and water have a completely opposite effect. Based on fractal and contribution analyses, the different effects of cropland are ascribed to the greater vegetation coverage from farming activity in spring than in autumn. The opposite effect of cropland on air pollution reveals that green coverage and human activity also influence AOD patterns. Given that serious concerns have been raised regarding the effects of built-up areas, bare land and agricultural air pollutant emissions, this study will add fundamental knowledge of the understanding of the key factors influencing urban air quality.

  18. Organic aerosols

    SciTech Connect

    Penner, J.E.

    1994-01-01

    Organic aerosols scatter solar radiation. They may also either enhance or decrease concentrations of cloud condensation nuclei. This paper summarizes observed concentrations of aerosols in remote continental and marine locations and provides estimates for the sources of organic aerosol matter. The anthropogenic sources of organic aerosols may be as large as the anthropogenic sources of sulfate aerosols, implying a similar magnitude of direct forcing of climate. The source estimates are highly uncertain and subject to revision in the future. A slow secondary source of organic aerosols of unknown origin may contribute to the observed oceanic concentrations. The role of organic aerosols acting as cloud condensation nuclei (CCN) is described and it is concluded that they may either enhance or decrease the ability of anthropogenic sulfate aerosols to act as CCN.

  19. A FIB/TEM Study of a Complex Wark-Lovering Rim on a Vigarano CAI

    NASA Technical Reports Server (NTRS)

    Keller, L. P.; Needham, A. W.; Messenger, S.

    2013-01-01

    Wark-Lovering (WL) rims are thin multilayered mineral sequences that surround most Ca, Al-rich inclusions (CAIs). Several processes have been proposed for WL rim formation, including condensation, flash-heating or reaction with a nebular reservoir, or combinations of these [e.g. 1-7], but no consensus exists. Our previous coordinated transmission electron microscope (TEM) and NanoSIMS O isotopic measurements showed that a WL rim experienced flash heating events in a nebular environment with planetary O isotopic composition, distinct from the (16)O-rich formation environment [6]. Our efforts have focused on CAIs from the CV(sub red) chondrites, especially Vigarano, because these have escaped much of the parent body alteration effects that are common in CAIs from CV(sub ox) group.

  20. Oxygen reservoirs in the early solar nebula inferred from an allende CAI

    PubMed

    Young; Russell

    1998-10-16

    Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta17O against delta18O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in 17O and 18O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive 16O-rich component of CAIs.

  1. Oxygen reservoirs in the early solar nebula inferred from an Allende CAI.

    PubMed

    Young, E D; Russell, S S

    1998-10-16

    Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta (17)O against delta (18)O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in (17)O and (18)O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive (16)O-rich component of CAIs.

  2. Germination of white radish, buckwheat and qing-geng-cai under low pressure in closed environment.

    PubMed

    Hinokuchi, Tsutomu; Oshima, Satoshi; Hashimoto, Hirofumi

    2004-11-01

    In order to cultivate plants under low pressure in closed environment, the germination rate of seeds of white radish was investigated under low pressure, low oxygen partial pressure and condition of pure oxygen. The result of these experiments showed that the germination rate was affected by the oxygen partial pressure. From this fact, it is possible to lower the total pressure by using only the pure oxygen in germination. Furthermore, the germination rates of seeds of buckwheat and qing-geng-cai were also investigated in pure oxygen for the comparison. Consequently, though tendency in germination rate of white radish was similar to qing-geng-cai, it was different from buckwheat.

  3. On relationship between aerosols and PM2.5

    NASA Astrophysics Data System (ADS)

    Sano, Itaru; Mukai, Sonoyo; Nakata, Makiko

    2015-04-01

    Since aerosol optical thickness (AOT) is a key parameter of aerosols and description of the Earth's radiation budget, it is widely measured from ground sun photometer network NASA/AERONET [Holben et al., 1998] and from satellite. Fine and surface level aerosol particle called PM2.5, whose diameter is 2.5 μ m or less, is a well-known parameter for understanding polluted level of air. Smirnov et al. reported a good agreement between ground based AERONET AOT (870 nm) and dust concentrations at Barbados [Smirnov et al., 2000]. Wang and Christopher founded a good correlation between satellite based MODIS AOT product and PM2.5 in Alabama area [Wang and 2003]. Long range transported dusts, particularly Asian dust events, are easy to change the vertical profile of aerosol extinction. The vertical profile is important to estimate PM information because both AOT information measured from ground or satellite are integrated value of aerosol extinction from ground to space, i.e. columnar AOT. Thus, we have also proposed correlations between ground level PM2.5 and AERONET AOT (670 nm) in two cases of ordinary air condition and dusty days [Sano et al., 2010]. In this work, we investigate the relationship between PM2.5 and AERONET AOT considering LIDAR measurements. Note that all of instruments are set up at the roof of the University building (50 m) and collocated in 10 m area. Surface-level AOT is derived from AERONET AOT multiplied by an averaged vertical aerosol extinction given by LIDAR. Note that the definition of surface-level AOT in this work is assumed as AOT up to 500 m height. Introduction of surface-level AOT enables to avoid the contamination of dusty aerosol signal existing at high altitude from columnar AOT. The cloud aerosol imager (CAI) on GOSAT satellite has four observing wavelengths, 380, 670, 870 nm, and 1.6 μ m. In this work three channels are selected to estimate aerosol information. Look-up table (LUT) method is applied to estimate the optical properties

  4. Stable Magnesium Isotope Variation in Melilite Mantle of Allende Type B1 CAI EK 459-5-1

    NASA Technical Reports Server (NTRS)

    Kerekgyarto, A. G.; Jeffcoat, C. R.; Lapen, T. J.; Andreasen, R.; Righter, M.; Ross, D. K.

    2014-01-01

    Ca-Al-rich inclusions (CAIs) are the earliest formed crystalline material in our solar system and they record early Solar System processes. Here we present petrographic and delta Mg-25 data of melilite mantles in a Type B1 CAI that records early solar nebular processes.

  5. The Matriculation Science Curriculum of the USM in the Context of the PPI and CAI Modes of Instruction.

    ERIC Educational Resources Information Center

    Cheng, Chuah Chong; Seng, Chin Pin

    1985-01-01

    Discusses philosophy, aims and objectives, and structure of the Matriculation Science Curriculum of the University Sains Malaysia. Includes comments on instructional strategies, individualized learning, programmed instruction, systems approach to computer-assisted instruction (CAI) implementation, CAI authoring system, and various program…

  6. Gender Role, Gender Identity and Sexual Orientation in CAIS ("XY-Women") Compared With Subfertile and Infertile 46,XX Women.

    PubMed

    Brunner, Franziska; Fliegner, Maike; Krupp, Kerstin; Rall, Katharina; Brucker, Sara; Richter-Appelt, Hertha

    2016-01-01

    The perception of gender development of individuals with complete androgen insensitivity syndrome (CAIS) as unambiguously female has recently been challenged in both qualitative data and case reports of male gender identity. The aim of the mixed-method study presented was to examine the self-perception of CAIS individuals regarding different aspects of gender and to identify commonalities and differences in comparison with subfertile and infertile XX-chromosomal women with diagnoses of Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) and polycystic ovary syndrome (PCOS). The study sample comprised 11 participants with CAIS, 49 with MRKHS, and 55 with PCOS. Gender identity was assessed by means of a multidimensional instrument, which showed significant differences between the CAIS group and the XX-chromosomal women. Other-than-female gender roles and neither-female-nor-male sexes/genders were reported only by individuals with CAIS. The percentage with a not exclusively androphile sexual orientation was unexceptionally high in the CAIS group compared to the prevalence in "normative" women and the clinical groups. The findings support the assumption made by Meyer-Bahlburg ( 2010 ) that gender outcome in people with CAIS is more variable than generally stated. Parents and professionals should thus be open to courses of gender development other than typically female in individuals with CAIS.

  7. The Interplay between Different Forms of CAI and Students' Preferences of Learning Environment in the Secondary Science Class

    ERIC Educational Resources Information Center

    Chang, Chun-Yen; Tsai, Chin-Chung

    2005-01-01

    This evaluation study investigated the effects of a teacher-centered versus student-centered computer-assisted instruction (CAI) on 10th graders' earth science student learning outcomes. This study also explored whether the effects of different forms of computer-assisted instruction (CAI) on student learning outcomes were influenced by student…

  8. Revision of the Oriental leafhopper genus Destinoides Cai & He (Hemiptera: Cicadellidae: Ledrinae), with a new synonym and two new combinations.

    PubMed

    Sun, Jing; Webb, Michael D; Zhang, Yalin

    2014-01-01

    The leafhopper genus Destinoides Cai & He is revised to include two species D. latifrons (Walker 1851, Ledra) n. comb. and D. conspicuus (Distant 1907, Petalocephala) n. comb. Destinoides fasciata Cai & He, 2000 is placed as a junior synonym of D. latifrons, syn. nov. These two species are redescribed and illustrated in detail and a key is given based on the males.

  9. [CAIS correction for blood matrix effect on determination of lead concentration and isotope ratio by ICP-MS].

    PubMed

    Zeng, Jing; Wang, Xiao-yan; Liu, Hu-sheng; Dun, Zhe; Zhai, Lei; Wang, Jing-yu

    2007-02-01

    The research studied the influence of matrix effect on the determination of lead concentration and isotope ratio through simulating blood matrix, and its correction by common analyte internal standardization (CAIS) method. The experiment results showed that CAIS method was suitable for the multi-element-matrix. The relative errors between the determined and the true concentration values are 20% (without correction), 8% (by conventional internal reference correction) and 2% (by CAIS correction), respectively. Otherwise, the influence of matrix effect and its correction for isotope ratio determination are not that obvious. Similarity of the mass number and properties between internal reference and analyte elements seems not important for CAIS correction, since very close correction results were obtained by using Tl and Dy as internal reference elements. Besides, correction results are not affected by different matrix dilution. Reliability and practicality of CAIS were proved by bovine blood standard material determination.

  10. Real-Time Graphics for CAI: A Rudimentary Grammar and Demonstration Program.

    ERIC Educational Resources Information Center

    Winn, William

    This paper focuses on graphics and how they can be created, in real time, from information stored in a database, and the application of this technique to computer-assisted instruction (CAI). It is noted that this is a special case of the general trend towards endowing instructional systems with a degree of decision-making or design expertise, as…

  11. Role of Computer Assisted Instruction (CAI) in an Introductory Computer Concepts Course.

    ERIC Educational Resources Information Center

    Skudrna, Vincent J.

    1997-01-01

    Discusses the role of computer assisted instruction (CAI) in undergraduate education via a survey of related literature and specific applications. Describes an undergraduate computer concepts course and includes appendices of instructions, flowcharts, programs, sample student work in accounting, COBOL instructional model, decision logic in a…

  12. Toward a Market Success for CAI; An Overview of the TICCIT Program.

    ERIC Educational Resources Information Center

    Stetten, Kenneth J.

    A new computer-assisted instruction (CAI) system for college teaching is being tested in two locations by the MITRE Corporation. The system, called TICCIT (Time-Share Interactive Computer-Controlled Information Television), now interacts with more than 100 students, each moving at his own pace, for four semesters of community college math and…

  13. Effectiveness of Computer Assisted Instructions (CAI) in Teaching of Mathematics at Secondary Level

    NASA Astrophysics Data System (ADS)

    Dhevakrishnan, R.; Devi, S.; Chinnaiyan, K.

    2012-09-01

    The present study was aimed at effectiveness of computer assisted instructions (CAI) in teaching of mathematics at secondary level adopted experimental method and observing the difference between (CAI) and traditional method. A sample of sixty (60) students of IX class in VVB Matriculation Higher Secondary School at Elayampalayam, Namakkal district were selected for a sample and sample was divided into two group namely experiment and control group. The experimental group consisted 30 students who were taught 'Mensurationí by the computer assisted instructions and the control groups comprising 30 students were taught by the conventional method of teaching. Data analyzed using mean, S.D. and t-test. Findings of the study clearly point out that significant increase in the mean gain scores has been found in the post test scores of the experimental group. Significant differences have been found between the control group and experimental group on post test gain scores. The experiment group, which was taught by the CAI showed better, learning. The conclusion is evident that the CAI is an effective media of instruction for teaching Mathematics at secondary students.s

  14. Web Pages: An Effective Method of Providing CAI Resource Material in Histology.

    ERIC Educational Resources Information Center

    McLean, Michelle

    2001-01-01

    Presents research that introduces computer-aided instruction (CAI) resource material as an integral part of the second-year histology course at the University of Natal Medical School. Describes the ease with which this software can be developed, using limited resources and available skills, while providing students with valuable learning…

  15. The Development and Utilization of Mobile CAI for the Education of Nurses in Remote Areas.

    ERIC Educational Resources Information Center

    Hall, Keith A.

    In providing for inservice nursing educational opportunities, the obvious advantages of the computer-assisted instruction (CAI) mobile system are its inherent interactive quality and the flexibility of scheduling made available to those who are already working in a field. The rationale for the development of the system is based on the past and…

  16. The Role of the CAI-1 Fatty Acid Tail in the Vibrio cholerae Quorum Sensing Response

    PubMed Central

    Perez, Lark J.; Ng, Wai-Leung; Marano, Paul; Brook, Karolina; Bassler, Bonnie L.; Semmelhack, Martin F.

    2013-01-01

    Quorum sensing is a mechanism of chemical communication among bacteria that enables collective behaviors. In V. cholerae, the etiological agent of the disease cholera, quorum sensing controls group behaviors including virulence factor production and biofilm formation. The major V. cholerae quorum-sensing system consists of the extracellular signal molecule called CAI-1 and its cognate membrane bound receptor called CqsS. Here, the ligand binding activity of CqsS is probed with structural analogs of the natural signal. Enabled by our discovery of a structurally simplified analog of CAI-1, we prepared and analyzed a focused library. The molecules were designed to probe the effects of conformational and structural changes along the length of the fatty acid tail of CAI-1. Our results, combined with pharmacophore modeling, suggest a molecular basis for signal molecule recognition and receptor fidelity with respect to the fatty acid tail portion of CAI-1. These efforts provide novel probes to enhance discovery of anti-virulence agents for the treatment of V. cholerae. PMID:23092313

  17. Assessing the Impact of Computer-Assisted Instruction (CAI) in Undergraduate Latin American Studies.

    ERIC Educational Resources Information Center

    Child, Jack

    This paper assesses the impact of using computer-assisted instruction (CAI) in three American University undergraduate classes, a General Education survey course on Latin America (taught in English), and two Spanish language courses. The courses utilized both commercial software programs and software programs authored by faculty using Macintosh…

  18. Examination and Application of Formative Evaluation for Author Utilization During the Preparation of a CAI Course.

    ERIC Educational Resources Information Center

    Ward, Marjorie Ellen

    A study was devised to investigate the use of formative evaluation during the preparation of a course entitled "Education of Visually Handicapped Children" designed for presentation to students through computer-assisted instruction (CAI). Various models for formative evaluation were examined, the Baker and Schutz cycle for instructional product…

  19. On the Design and Development of Pedagogy-First CAI Tools for CS Education.

    ERIC Educational Resources Information Center

    Vadaparty, K.; And Others

    This paper presents the implications of an ongoing project on the design and development of multimedia instructional material for teaching and learning computer science topics at both graduate and undergraduate levels. Important pedagogical requirements that CAI software should satisfy include: (1) animation of the changes in tree topologies; (2)…

  20. Development of a Computer-Assisted Instruction (CAI) Program on the Delphi Technique.

    ERIC Educational Resources Information Center

    McCurdy, Carol

    The concept of Delphi technique was presented in a computer-assisted instruction (CAI) module designed for educational administration classes or inservice training of administrators. Instructional Dialogue Facility (IDF) Author Language on a 2000F Hewlett-Packard time-sharing system was used to write the sequence. Instructional objectives,…

  1. Consumption of fa cai Nostoc soup: a potential for BMAA exposure from Nostoc cyanobacteria in China?

    PubMed

    Roney, Britton R; Renhui, Li; Banack, Sandra Anne; Murch, Susan; Honegger, Rosmarie; Cox, Paul Alan

    2009-01-01

    Grown in arid regions of western China the cyanobacterium Nostoc flagelliforme--called fa cai in Mandarin and fat choy in Cantonese--is wild-harvested and used to make soup consumed during New Year's celebrations. High prices, up to $125 USD/kg, led to overharvesting in Inner Mongolia, Ningxia, Gansu, Qinghai, and Xinjiang. Degradation of arid ecosystems, desertification, and conflicts between Nostoc harvesters and Mongol herdsmen concerned the Chinese environmental authorities, leading to a government ban of Nostoc commerce. This ban stimulated increased marketing of a substitute made from starch. We analysed samples purchased throughout China as well as in Chinese markets in the United States and the United Kingdom. Some were counterfeits consisting of dyed starch noodles. A few samples from California contained Nostoc flagelliforme but were adulterated with starch noodles. Other samples, including those from the United Kingdom, consisted of pure Nostoc flagelliforme. A recent survey of markets in Cheng Du showed no real Nostoc flagelliforme to be marketed. Real and artificial fa cai differ in the presence of beta-N-methylamino-L-alanine (BMAA). Given its status as a high-priced luxury food, the government ban on collection and marketing, and the replacement of real fa cai with starch substitutes consumed only on special occasions, it is anticipated that dietary exposure to BMAA from fa cai will be reduced in the future in China.

  2. A Cross-National CAI Tool To Support Learning Operations Decision-Making and Market Analysis.

    ERIC Educational Resources Information Center

    Mockler, Robert J.; Afanasiev, Mikhail Y.; Dologite, Dorothy G.

    1999-01-01

    Describes bicultural (United States and Russia) development of a computer-aided instruction (CAI) tool to learn management decision-making using information systems technologies. The program has been used with undergraduate and graduate students in both countries; it integrates free and controlled market concepts and combines traditional computer…

  3. Computer-Assisted Instruction in Engineering Dynamics. CAI-Systems Memo Number 18.

    ERIC Educational Resources Information Center

    Sheldon, John W.

    A 90-minute computer-assisted instruction (CAI) unit course supplemented by a 1-hour lecture on the dynamic nature of three-dimensional rotations and Euler angles was given to 29 undergraduate engineering students. The area of Euler angles was selected because it is essential to problem-working in three-dimensional rotations of a rigid body, yet…

  4. An ion microprobe study of CAIs from CO3 meteorites. [Abstract only

    NASA Technical Reports Server (NTRS)

    Russell, S. S.; Greenwood, R. C.; Fahey, A. J.; Huss, G. R.; Wasserburg, G. J.

    1994-01-01

    When attempting to interpret the history of Ca, Al-rich inclusions (CAIs) it is often difficult to distinguish between primary features inherited from the nebula and those produced during secondary processing on the parent body. We have undertaken a systematic study of CAIs from 10 CO chondrites, believed to represent a metamorphic sequence with the goal of distinguishing primary and secondary features. ALHA 77307 (3.0), Colony (3.0), Kainsaz (3.1), Felix (3.2), ALH 82101 (3.3), Ornans (3.3), Lance (3.4), ALHA 77003 (3.5), Warrenton (3.6), and Isna (3.7) were examined by Scanning Electron Microscopy (SEM) and optical microscopy. We have identified 141 CAIs within these samples, and studied in detail the petrology of 34 inclusions. The primary phases in the lower petrologic types are spinel, melilite, and hibonite. Perovskite, FeS, ilmenite, anorthite, kirschsteinite, and metallic Fe are present as minor phases. Melilite becomes less abundant in higher petrologic types and was not detected in chondrites of type 3.5 and above, confirming previous reports that this mineral easily breaks down during heating. Iron, an element that would not be expected to condense at high temperatures, has a lower abundance in spinel from low-petrologic-type meteorites than those of higher grade, and CaTiO3 is replaced by FeTiO3 in meteorites of higher petrologic type. The abundance of CAIs is similar in each meteorite. Eight inclusions have been analyzed by ion probe. The results are summarized. The results obtained to date show that CAIs in CO meteorites, like those from other meteorite classes, contain Mg* and that Mg in some inclusions has been redistributed.

  5. Formation of halogen-induced secondary organic aerosol (XOA)

    NASA Astrophysics Data System (ADS)

    Kamilli, Katharina; Ofner, Johannes; Zetzsch, Cornelius; Held, Andreas

    2013-04-01

    Reactive halogen species (RHS) are very important due to their potential of stratospheric ozone depletion and surface ozone destruction. RHS seem to interact with precursors of secondary organic aerosol (SOA) similarly to common atmospheric oxidants like OH radicals and ozone. The potential interaction of RHS with preformed SOA has recently been studied (Ofner et al., 2012). Although aerosol formation from reaction of RHS with typical SOA precursors was previously studied (e.g. Cai et al., 2006), no data are available on bromine-induced aerosol formation from organic precursors yet. An aerosol smog-chamber was used to examine the halogen-induced secondary organic aerosol (XOA) formation under atmospheric conditions using simulated sunlight. With a concentration of 10 ppb for the organic precursor, 2 ppb for molecular chlorine, and 10 ppb for molecular bromine, the experimental setup is close to ambient conditions. By combined measurements of the aerosol size distribution, ozone and NOx mixing ratios, as well as the decay of the organic precursor, aerosol yields and aerosol growth rates were determined. The decay of the organic precursor was analyzed by capillary gas chromatography coupled with flame-ionization detection (GC-FID) and the aerosol size distribution was measured using a Scanning Mobility Particle Sizer (SMPS). Additionally, with the decay rate of the precursor and the calculated photolysis rates of molecular halogen species, based on the well-known spectrum of the solar simulator, mechanistic details on the XOA formation pathways can be determined. We observed XOA formation even at very low precursor and RHS concentrations with a diameter mode at 10-20 nm and a number concentration up to 1000000 particles cm-3. While the XOA formation from chlorine is very rapid, the interaction of bromine with the organic precursors is about five times slower. The aerosol yield reached maximum values of 0.01 for the reaction of chlorine with α-pinene and 0.0004 for

  6. Compound ultrarefractory CAI-bearing inclusions from CV3 carbonaceous chondrites

    NASA Astrophysics Data System (ADS)

    Ivanova, Marina A.; Krot, Alexander N.; Nagashima, Kazuhide; MacPherson, Glenn J.

    2012-12-01

    Abstract-Two compound calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>), 3N from the oxidized CV chondrite Northwest Africa (NWA) 3118 and 33E from the reduced CV chondrite Efremovka, contain ultrarefractory (UR) inclusions. 3N is a forsterite-bearing type B (FoB) <span class="hlt">CAI</span> that encloses UR inclusion 3N-24 composed of Zr,Sc,Y-rich oxides, Y-rich perovskite, and Zr,Sc-rich Al,Ti-diopside. 33E contains a fluffy type A (FTA) <span class="hlt">CAI</span> and UR <span class="hlt">CAI</span> 33E-1, surrounded by Wark-Lovering rim layers of spinel, Al-diopside, and forsterite, and a common forsterite-rich accretionary rim. 33E-1 is composed of Zr,Sc,Y-rich oxides, Y-rich perovskite, Zr,Sc,Y-rich pyroxenes (Al,Ti-diopside, Sc-rich pyroxene), and gehlenite. 3N-24's UR oxides and Zr,Sc-rich Al,Ti-diopsides are 16O-poor (Δ17O approximately -2‰ to -5‰). Spinel in 3N-24 and spinel and Al-diopside in the FoB <span class="hlt">CAI</span> are 16O-rich (Δ17O approximately -23 ± 2‰). 33E-1's UR oxides and Zr,Sc-rich Al,Ti-diopsides are 16O-depleted (Δ17O approximately -2‰ to -5‰) vs. Al,Ti-diopside of the FTA <span class="hlt">CAI</span> and spinel (Δ17O approximately -23 ± 2‰), and Wark-Lovering rim Al,Ti-diopside (Δ17O approximately -7‰ to -19‰). We infer that the inclusions experienced multistage formation in nebular regions with different oxygen-isotope compositions. 3N-24 and 33E-1's precursors formed by evaporation/condensation above 1600 °C. 3N and 33E's precursors formed by condensation and melting (3N only) at significantly lower temperatures. 3N-24 and 3N's precursors aggregated into a compound object and experienced partial melting and thermal annealing. 33E-1 and 33E avoided melting prior to and after aggregation. They acquired Wark-Lovering and common forsterite-rich accretionary rims, probably by condensation, followed by thermal annealing. We suggest 3N-24 and 33E-1 originated in a 16O-rich gaseous reservoir and subsequently experienced isotope exchange in a 16O-poor gaseous reservoir. Mechanism and timing of oxygen-isotope exchange remain</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750022313','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750022313"><span id="translatedtitle">Alternative communication network designs for an operational Plato 4 <span class="hlt">CAI</span> system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mobley, R. E., Jr.; Eastwood, L. F., Jr.</p> <p>1975-01-01</p> <p>The cost of alternative communications networks for the dissemination of PLATO IV computer-aided instruction (<span class="hlt">CAI</span>) was studied. Four communication techniques are compared: leased telephone lines, satellite communication, UHF TV, and low-power microwave radio. For each network design, costs per student contact hour are computed. These costs are derived as functions of student population density, a parameter which can be calculated from census data for one potential market for <span class="hlt">CAI</span>, the public primary and secondary schools. Calculating costs in this way allows one to determine which of the four communications alternatives can serve this market least expensively for any given area in the U.S. The analysis indicates that radio distribution techniques are cost optimum over a wide range of conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940011928','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940011928"><span id="translatedtitle">Limited subsolidus diffusion in type B1 <span class="hlt">CAI</span>: Evidence from Ti distribution in spinel</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Meeker, G. P.; Quick, J. E.; Paque, Julie M.</p> <p>1993-01-01</p> <p>Most models of calcium aluminum-rich inclusions (<span class="hlt">CAI</span>) have focused on early stages of formation by equilibrium crystallization of a homogeneous liquid. Less is known about the subsolidus cooling history of <span class="hlt">CAI</span>. Chemical and isotopic heterogeneties on a scale of tens to hundreds of micrometers (e.g. MacPherson et al. (1989) and Podosek, et al. (1991)) suggest fairly rapid cooling with a minimum of subsolidus diffusion. However, transmission electron microscopy indicates that solid state diffusion may have been an important process at a smaller scale (Barber et al. 1984). If so, chemical evidence for diffusion could provide constraints on cooling times and temperatures. With this in mind, we have begun an investigation of the Ti distribution in spinels from two type B1 <span class="hlt">CAI</span> from Allende to determine if post-crystallization diffusion was a significant process. The type B1 <span class="hlt">CAIs</span>, 3529Z and 5241 have been described by Podosek et al. (1991) and by El Goresy et al. (1985) and MacPherson et al. (1989). We have analyzed spinels in these inclusions using the electron microprobe. These spinels are generally euhedral, range in size from less than 10 to 15 micron and are poikilitically enclosed by millimeter-sized pyroxene, melilite, and anorthite. Analyses were obtained from both the mantles and cores of the inclusions. Compositions of pyroxene in the vicinity of individual spinel grains were obtained by analyzing at least two points on opposite sides of the spinel and averaging the compositions. The pyroxene analyses were obtained within 15 microns of the spinel-pyroxene interface. No compositional gradients were observed within single spinel crystals. Ti concentrations in spinels included within pyroxene, melilite, and anorthite are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MS%26E..148a2083P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MS%26E..148a2083P"><span id="translatedtitle">Numerical investigation of <span class="hlt">CAI</span> Combustion in the Opposed- Piston Engine with Direct and Indirect Water Injection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pyszczek, R.; Mazuro, P.; Teodorczyk, A.</p> <p>2016-09-01</p> <p>This paper is focused on the <span class="hlt">CAI</span> combustion control in a turbocharged 2-stroke Opposed-Piston (OP) engine. The barrel type OP engine arrangement is of particular interest for the authors because of its robust design, high mechanical efficiency and relatively easy incorporation of a Variable Compression Ratio (VCR). The other advantage of such design is that combustion chamber is formed between two moving pistons - there is no additional cylinder head to be cooled which directly results in an increased thermal efficiency. Furthermore, engine operation in a Controlled Auto-Ignition (<span class="hlt">CAI</span>) mode at high compression ratios (CR) raises a possibility of reaching even higher efficiencies and very low emissions. In order to control <span class="hlt">CAI</span> combustion such measures as VCR and water injection were considered for indirect ignition timing control. Numerical simulations of the scavenging and combustion processes were performed with the 3D CFD multipurpose AVL Fire solver. Numerous cases were calculated with different engine compression ratios and different amounts of directly and indirectly injected water. The influence of the VCR and water injection on the ignition timing and engine performance was determined and their application in the real engine was discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18..132W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18..132W"><span id="translatedtitle">A novel method to retrieve <span class="hlt">Aerosol</span> Optical Thickness from high-resolution optical satellite <span class="hlt">images</span> using an extended version of the Haze Optimized Transform (HOTBAR)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilson, Robin; Milton, Edward; Nield, Joanna</p> <p>2016-04-01</p> <p><span class="hlt">Aerosol</span> Optical Thickness (AOT) data has many important applications including atmospheric correction of satellite imagery and monitoring of particulate matter air pollution. Current data products are generally available at a kilometre-scale resolution, but many applications require far higher resolutions. For example, particulate matter concentrations vary on a metre-scale, and thus data products at a similar scale are required to provide accurate assessments of particle densities and allow effective monitoring of air quality and analysis of local air quality effects on health. A novel method has been developed which retrieves per-pixel AOT values from high-resolution (~30m) satellite data. This method is designed to work over a wide range of land covers - including both bright and dark surfaces - and requires only standard visible and near-infrared data, making it applicable to a range of data from sensors such as Landsat, SPOT and Sentinel-2. The method is based upon an extension of the Haze Optimized Transform (HOT). The HOT was originally designed for assessing areas of thick haze in satellite imagery by calculating a 'haziness' value for each pixel in an <span class="hlt">image</span> as the distance from a 'Clear Line' in feature space, defined by the high correlation between visible bands. Here, we adapt the HOT method and use it to provide AOT data instead. Significant extensions include Monte Carlo estimation of the 'Clear Line', object-based correction for land cover, and estimation of AOT from the haziness values through radiative transfer modelling. This novel method will enable many new applications of AOT data that were impossible with previously available low-resolution data, and has the potential to contribute significantly to our understanding of the air quality on health, the accuracy of satellite <span class="hlt">image</span> atmospheric correction and the role of <span class="hlt">aerosols</span> in the climate system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25186361','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25186361"><span id="translatedtitle">Crystal structures of hydrates of simple inorganic salts. II. Water-rich calcium bromide and iodide hydrates: CaBr2 · 9H2O, <span class="hlt">CaI</span>2 · 8H2O, <span class="hlt">CaI</span>2 · 7H2O and <span class="hlt">CaI</span>2 · 6.5H2O.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hennings, Erik; Schmidt, Horst; Voigt, Wolfgang</p> <p>2014-09-01</p> <p>Single crystals of calcium bromide enneahydrate, CaBr(2) · 9H2O, calcium iodide octahydrate, <span class="hlt">CaI</span>(2) · 8H2O, calcium iodide heptahydrate, <span class="hlt">CaI</span>(2) · 7H2O, and calcium iodide 6.5-hydrate, <span class="hlt">CaI</span>(2) · 6.5H2O, were grown from their aqueous solutions at and below room temperature according to the solid-liquid phase diagram. The crystal structure of <span class="hlt">CaI</span>(2) · 6.5H2O was redetermined. All four structures are built up from distorted Ca(H2O)8 antiprisms. The antiprisms of the iodide hydrate structures are connected either via trigonal-plane-sharing or edge-sharing, forming dimeric units. The antiprisms in calcium bromide enneahydrate are monomeric. PMID:25186361</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EOSTr..95Q..60S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EOSTr..95Q..60S"><span id="translatedtitle">Assessing new remote sensing <span class="hlt">aerosol</span> detection algorithms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schultz, Colin</p> <p>2014-02-01</p> <p>Atmospheric <span class="hlt">aerosols</span> affect the weather and climate by changing cloud formation and the energy balance and, depending on their type and concentration, can negatively affect air quality. Important atmospheric <span class="hlt">aerosols</span> include dust, ash, volcanic sulfate <span class="hlt">aerosols</span>, sea salt, biogenic particles, urban/industrial pollution, and smoke. For more than a decade, the twin Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometers (MODIS) aboard NASA's Aqua and Terra satellites have provided regular global assessments of <span class="hlt">aerosol</span> loading, and now, following its 2011 launch, the Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite is ready to contribute to that assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26070573','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26070573"><span id="translatedtitle"><span class="hlt">Aerosolized</span> Antibiotics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Restrepo, Marcos I; Keyt, Holly; Reyes, Luis F</p> <p>2015-06-01</p> <p>Administration of medications via <span class="hlt">aerosolization</span> is potentially an ideal strategy to treat airway diseases. This delivery method ensures high concentrations of the medication in the targeted tissues, the airways, with generally lower systemic absorption and systemic adverse effects. <span class="hlt">Aerosolized</span> antibiotics have been tested as treatment for bacterial infections in patients with cystic fibrosis (CF), non-CF bronchiectasis (NCFB), and ventilator-associated pneumonia (VAP). The most successful application of this to date is treatment of infections in patients with CF. It has been hypothesized that similar success would be seen in NCFB and in difficult-to-treat hospital-acquired infections such as VAP. This review summarizes the available evidence supporting the use of <span class="hlt">aerosolized</span> antibiotics and addresses the specific considerations that clinicians should recognize when prescribing an <span class="hlt">aerosolized</span> antibiotic for patients with CF, NCFB, and VAP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eosweb.larc.nasa.gov/project/misr/gallery/global_aerosols','SCIGOV-ASDC'); return false;" href="https://eosweb.larc.nasa.gov/project/misr/gallery/global_aerosols"><span id="translatedtitle">Global <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://eosweb.larc.nasa.gov/">Atmospheric Science Data Center </a></p> <p></p> <p>2013-04-19</p> <p>... sizes and from multiple sources, including biomass burning, mineral dust, sea salt and regional industrial pollution. A color scale is ... desert source region. Deserts are the main sources of mineral dust, and MISR obtains <span class="hlt">aerosol</span> optical depth at visible wavelengths ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016E%26PSL.440...62A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016E%26PSL.440...62A"><span id="translatedtitle">Oxygen isotopes in the early protoplanetary disk inferred from pyroxene in a classical type B <span class="hlt">CAI</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aléon, Jérôme</p> <p>2016-04-01</p> <p>A major unanswered question in solar system formation is the origin of the oxygen isotopic dichotomy between the Sun and the planets. Individual Calcium-Aluminum-rich inclusions (<span class="hlt">CAIs</span>) from CV chondrites exhibit almost the full isotopic range, but how their composition evolved is still unclear, which prevents robust astrochemical conclusions. A key issue is notably the yet unsolved origin of the 16O-rich isotopic composition of pyroxene in type B <span class="hlt">CAIs</span>. Here, I report an in-situ oxygen isotope study of the archetypal type B <span class="hlt">CAI</span> USNM-3529-Z from Allende with emphasis on the isotopic composition of pyroxene and its isotopic and petrographic relationships with other major minerals. The O isotopic composition of pyroxene is correlated with indicators of magmatic growth, indicating that the pyroxene evolved from a 16O-poor composition and became progressively enriched in 16O during its crystallization, contrary to the long held assumption that pyroxene was initially 16O-rich. This variation is well explained by isotopic exchange between a 16O-poor partial melt having the isotopic composition of melilite and a 16O-rich gas having the isotopic composition of spinel, during pyroxene crystallization. The isotopic evolution of 3529-Z is consistent with formation in an initially 16O-rich environment where spinel and gehlenitic melilite crystallized, followed by a 16O-depletion associated with melilite partial melting and recrystallization and finally a return to the initial 16O-rich environment before pyroxene crystallization. This strongly suggests that the environment of <span class="hlt">CAI</span> formation was globally 16O-rich, with local 16O-depletions systematically associated with high temperature events. The Al/Mg isotopic systematics of 3529-Z further indicates that this suite of isotopic changes occurred in the first 150 000 yr of the solar system, during the main <span class="hlt">CAI</span> formation period. A new astrophysical setting is proposed, where the 16O-depletion occurs in an optically thin surface</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20090020501','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20090020501"><span id="translatedtitle">Rare Earth Element Measurements of Melilite and Fassaite in Allende <span class="hlt">Cai</span> by Nanosims</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ito, M.; Messenger, Scott</p> <p>2009-01-01</p> <p>The rare earth elements (REEs) are concentrated in <span class="hlt">CAIs</span> by approx. 20 times the chondritic average [e.g., 1]. The REEs in <span class="hlt">CAIs</span> are important to understand processes of <span class="hlt">CAI</span> formation including the role of volatilization, condensation, and fractional crystallization [1,2]. REE measurements are a well established application of ion microprobes [e.g., 3]. However the spatial resolution of REE measurements by ion microprobe (approx.20 m) is not adequate to resolve heterogeneous distributions of REEs among/within minerals. We have developed methods for measuring REE with the NanoSIMS 50L at smaller spatial scales. Here we present our initial measurements of REEs in melilite and fassaite in an Allende Type-A <span class="hlt">CAI</span> with the JSC NanoSIMS 50L. We found that the key parameters for accurate REE abundance measurements differ between the NanoSIMS and conventional SIMS, in particular the oxide-to-element ratios, the relative sensitivity factors, the energy distributions, and requisite energy offset. Our REE abundance measurements of the 100 ppm REE diopside glass standards yielded good reproducibility and accuracy, 0.5-2.5 % and 5-25 %, respectively. We determined abundances and spatial distributions of REEs in core and rim within single crystals of fassaite, and adjacent melilite with 5-10 m spatial resolution. The REE abundances in fassaite core and rim are 20-100 times CI abundance but show a large negative Eu anomaly, exhibiting a well-defined Group III pattern. This is consistent with previous work [4]. On the other hand, adjacent melilite shows modified Group II pattern with no strong depletions of Eu and Yb, and no Tm positive anomaly. REE abundances (2-10 x CI) were lower than that of fassaite. These patterns suggest that fassaite crystallized first followed by a crystallization of melilite from the residual melt. In future work, we will carry out a correlated study of O and Mg isotopes and REEs of the <span class="hlt">CAI</span> in order to better understand the nature and timescales of its</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003TrGeo...4...91B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003TrGeo...4...91B"><span id="translatedtitle">Tropospheric <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buseck, P. R.; Schwartz, S. E.</p> <p>2003-12-01</p> <p>It is widely believed that "On a clear day you can see forever," as proclaimed in the 1965 Broadway musical of the same name. While an admittedly beautiful thought, we all know that this concept is only figurative. Aside from Earth's curvature and Rayleigh scattering by air molecules, <span class="hlt">aerosols</span> - colloidal suspensions of solid or liquid particles in a gas - limit our vision. Even on the clearest day, there are billions of <span class="hlt">aerosol</span> particles per cubic meter of air.Atmospheric <span class="hlt">aerosols</span> are commonly referred to as smoke, dust, haze, and smog, terms that are loosely reflective of their origin and composition. <span class="hlt">Aerosol</span> particles have arisen naturally for eons from sea spray, volcanic emissions, wind entrainment of mineral dust, wildfires, and gas-to-particle conversion of hydrocarbons from plants and dimethylsulfide from the oceans. However, over the industrial period, the natural background <span class="hlt">aerosol</span> has been greatly augmented by anthropogenic contributions, i.e., those produced by human activities. One manifestation of this impact is reduced visibility (Figure 1). Thus, perhaps more than in other realms of geochemistry, when considering the composition of the troposphere one must consider the effects of these activities. The atmosphere has become a reservoir for vast quantities of anthropogenic emissions that exert important perturbations on it and on the planetary ecosystem in general. Consequently, much recent research focuses on the effects of human activities on the atmosphere and, through them, on the environment and Earth's climate. For these reasons consideration of the geochemistry of the atmosphere, and of atmospheric <span class="hlt">aerosols</span> in particular, must include the effects of human activities. (201K)Figure 1. Impairment of visibility by <span class="hlt">aerosols</span>. Photographs at Yosemite National Park, California, USA. (a) Low <span class="hlt">aerosol</span> concentration (particulate matter of aerodynamic diameter less than 2.5 μm, PM2.5=0.3 μg m-3; particulate matter of aerodynamic diameter less than 10 </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/3520704','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/3520704"><span id="translatedtitle">[Scintigraphy of pulmonary ventilation with 99mTc-DTPA radio-<span class="hlt">aerosol</span>. I. Semiotics of the static <span class="hlt">images</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Maini, C L; Bonetti, M G; Giordano, A; Pistelli, R; Antonelli Incalzi, R; Vecchioli, A; Galli, G</p> <p>1986-04-01</p> <p>Papers on deposition pattern analyses of radio-<span class="hlt">aerosol</span> lung scans are few and not easy to interpret as there is a general lack of technical standardization and the number of patients studied is not large. Moreover these reports have been generally obtained with non-hydrosoluble radioaerosols. In the present study 43 patients underwent conventional pulmonary function testing and lung scanning using small droplet (equal or less than 2 microns) polydisperse 99mTc-DTPA radioaerosol produced with the "Settling Bag System"--Medi 400 (Sorin). The scans were analysed by two methods: a semiquantitative method proposed by Taplin (SQT); an original simpler semiquantitative method (SQM). Correlations of SQT and SQM with FEV1 and MEF75 resulted highly significant (p less than 0,001). SQM proved to be superior to SQT as far as reproducibility is concerned. The following conclusions can be drawn: small particle 99mTc-DTPA <span class="hlt">aerosol</span> can be easily and cheaply produced by a commercial device; such a radioaerosol is well suited for the evaluation of small and large airways patency, as reflected by MEF75 and FEV1 respectively, with a diagnostic yield comparable to non-hydrosoluble radioaerosols; the original semiquantitative description of the deposition patterns proposed and validated in this study is quite easy to implement and it yields a high correlation with pulmonary function tests; moreover such an approach does not require digital data processing; the sensitivity of 99mTc-DTPA for the diagnosis of bronchial obstruction is very high and superior to routine pulmonary function tests; in addition the ventilation scan allows the topographical localization of the obstructions themselves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/944372','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/944372"><span id="translatedtitle">OXYGEN ISOTOPIC COMPOSITIONS OF THE ALLENDE TYPE C <span class="hlt">CAIs</span>: EVIDENCE FOR ISOTOPIC EXCHANGE DURING NEBULAR MELTING AND ASTEROIDAL THERMAL METAMORPHISM</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Krot, A N; Chaussidon, M; Yurimoto, H; Sakamoto, N; Nagashima, K; Hutcheon, I D; MacPherson, G J</p> <p>2008-02-21</p> <p>Based on the mineralogy and petrography, coarse-grained, igneous, anorthite-rich (Type C) calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>) in the CV3 carbonaceous chondrite Allende have been recently divided into three groups: (i) <span class="hlt">CAIs</span> with melilite and Al,Ti-diopside of massive and lacy textures (coarse grains with numerous rounded inclusions of anorthite) in a fine-grained anorthite groundmass (6-1-72, 100, 160), (ii) <span class="hlt">CAI</span> CG5 with massive melilite, Al,Ti-diopside and anorthite, and (iii) <span class="hlt">CAIs</span> associated with chondrule material: either containing chondrule fragments in their peripheries (ABC, TS26) or surrounded by chondrule-like, igneous rims (93) (Krot et al., 2007a,b). Here, we report in situ oxygen isotopic measurements of primary (melilite, spinel, Al,Ti-diopside, anorthite) and secondary (grossular, monticellite, forsterite) minerals in these <span class="hlt">CAIs</span>. Spinel ({Delta}{sup 17}O = -25{per_thousand} to -20{per_thousand}), massive and lacy Al,Ti-diopside ({Delta}{sup 17}O = -20{per_thousand} to -5{per_thousand}) and fine-grained anorthite ({Delta}{sup 17}O = -15{per_thousand} to -2{per_thousand}) in 100, 160 and 6-1-72 are {sup 16}O-enriched relative spinel and coarse-grained Al,Ti-diopside and anorthite in ABC, 93 and TS26 ({Delta}{sup 17}O ranges from -20{per_thousand} to -15{per_thousand}, from -15{per_thousand} to -5{per_thousand}, and from -5{per_thousand} to 0{per_thousand}, respectively). In 6-1-72, massive and lacy Al,Ti-diopside grains are {sup 16}O-depleted ({Delta}{sup 17}O {approx} -13{per_thousand}) relative to spinel ({Delta}{sup 17}O = -23{per_thousand}). Melilite is the most {sup 16}O-depleted mineral in all Allende Type C <span class="hlt">CAIs</span>. In <span class="hlt">CAI</span> 100, melilite and secondary grossular, monticellite and forsterite (minerals replacing melilite) are similarly {sup 16}O-depleted, whereas grossular in <span class="hlt">CAI</span> 160 is {sup 16}O-enriched ({Delta}{sup 17}O = -10{per_thousand} to -6{per_thousand}) relative to melilite ({Delta}{sup 17}O = -5{per_thousand} to -3{per_thousand}). We infer</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19920021861&hterms=lidar+imaging&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dlidar%2Bimaging','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19920021861&hterms=lidar+imaging&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dlidar%2Bimaging"><span id="translatedtitle"><span class="hlt">Aerosol</span> extinction measurements with CO2-lidar</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hagard, Arne; Persson, Rolf</p> <p>1992-01-01</p> <p>With the aim to develop a model for infrared extinction due to <span class="hlt">aerosols</span> in slant paths in the lower atmosphere we perform measurements with a CO2-lidar. Earlier measurements with a transmissometer along horizontal paths have been used to develop relations between <span class="hlt">aerosol</span> extinction and meteorological parameters. With the lidar measurements we hope to develop corresponding relations for altitude profiles of the <span class="hlt">aerosol</span> extinction in the infrared. An important application is prediction of detection range for infrared <span class="hlt">imaging</span> systems.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.V43J..02O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.V43J..02O"><span id="translatedtitle">The isotopic homogeneity in the early solar system: Revisiting the <span class="hlt">CAI</span> oxygen isotopic anomaly</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ozima, M.; Yamada, A.</p> <p>2009-12-01</p> <p>Since the first discovery of the mass-independently fractionated oxygen isotopes in anhydrous, high temperature Ca-Al rich inclusion minerals in carbonaceous meteorites (<span class="hlt">CAIs</span>) by Clayton et al. (1), their common occurrence in primitive meteorites has generally been regarded to reflect some fundamental process prevalent in the early solar nebula. The <span class="hlt">CAI</span> oxygen isotopic composition is uniquely characterized by (i) large mass independent isotopic fractionation and (ii) their isotopic data in an oxygen three isotope plot (δ17O - δ18O (δ17O ≡ {(17O/16O)/(17O/16O)SMOW - 1} × 1000) yield nearly a straight line with a slope 1.0. In establishing these characteristics, ion microprobe analyses has played a central role, especially an isotopic mapping technique (isotopography) was crucial (e.g., 2). The extraordinary oxygen isotopic ratio in <span class="hlt">CAIs</span> is widely attributed to the self-shielding absorption of UV radiation in CO, one of the dominant chemical compounds in the early solar nebula (3). However, the self-shielding scenario necessarily leads to the unusual prediction that a mean solar oxygen isotopic composition differs from most of planetary bodies including Earth, Moon, and Mars. If the self-shielding process were indeed responsible to the <span class="hlt">CAI</span> oxygen isotopic anomaly, this would require a fundamental revision of the current theory of the origin of the solar system, which generally assumes the initial total vaporization of nebula material to give rise to isotopic homogenization. The GENESIS mission launched in 2001(4), which collected oxygen in the solar wind was hoped to resolve the isotopic composition of the Sun. However, because of difficulties in correcting for instrumental and more importantly for intrinsic isotopic fractionation between the SW and the Sun, a final answer is yet to be seen (5). Here, we show on the basis of the oxygen isotopic fractionation systematics that the self shielding hypothesis cannot explain the key characteristics of the <span class="hlt">CAI</span> oxygen</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeCoA.169...99K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeCoA.169...99K"><span id="translatedtitle">26Al-26Mg chronology and oxygen isotope distributions of multiple melting for a Type C <span class="hlt">CAI</span> from Allende</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawasaki, Noriyuki; Kato, Chizu; Itoh, Shoichi; Wakaki, Shigeyuki; Ito, Motoo; Yurimoto, Hisayoshi</p> <p>2015-11-01</p> <p>Disequilibrium oxygen isotopic distributions of Ca-Al-rich inclusions (<span class="hlt">CAIs</span>) correspond to multiple melting events in the solar nebula. 26Al-26Mg systematics may be applicable for age differences among such melting events. We have carried out a coordinated study of detailed petrographic observations and in-situ oxygen and magnesium isotope measurements for a Type C <span class="hlt">CAI</span>, EK1-04-2, from the Allende CV3 meteorite to determine the melting events and their ages. The <span class="hlt">CAI</span> consists mainly of spinel, anorthite, olivine, and pyroxene, and has a core and mantle structure. Petrography of the core suggests that the crystallization sequence of the core minerals is from spinel, anorthite, olivine, and to pyroxene. The mantle has the same mineral assemblage as the core, and shows incomplete melting and solidification textures. Oxygen isotopic compositions of the minerals are distributed along the carbonaceous chondrite anhydrous mineral (CCAM) line (δ18O = -44‰ to +9‰), which indicates to preserve a chemical disequilibrium status in the <span class="hlt">CAI</span>. Spinel shows a 16O-rich signature (δ18O ∼ -43‰), while anorthite is 16O-poor (δ18O ∼ +8‰). Olivine and pyroxene in the core have the same oxygen isotopic composition (δ18O ∼ -15‰), which indicates their equilibrium. Olivine and pyroxene in the mantle have variable oxygen isotopic compositions and are slightly depleted in 16O (δ18O = -13‰ to -4‰) compared with the same minerals in the core. The 26Al-26Mg systematics is consistent with the disequilibrium status observed according to the petrography and oxygen isotopes. Spinel is plotted on a line of (26Al/27Al)0 = (3.5 ± 0.2) × 10-5, anorthite is plotted on a line of (-1 ± 5) × 10-7, and olivine and pyroxene in the core are plotted on a line of (-1 ± 7) × 10-6. Plots of olivine and pyroxene in the mantle are scattered below the isochron of these minerals in the core. This study indicates that the EK1-04-2 Type C <span class="hlt">CAI</span> underwent multiple heating events after the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ApJ...763L..33G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ApJ...763L..33G"><span id="translatedtitle">Variable and Extreme Irradiation Conditions in the Early Solar System Inferred from the Initial Abundance of 10Be in Isheyevo <span class="hlt">CAIs</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gounelle, Matthieu; Chaussidon, Marc; Rollion-Bard, Claire</p> <p>2013-02-01</p> <p>A search for short-lived 10Be in 21 calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>) from Isheyevo, a rare CB/CH chondrite, showed that only 5 <span class="hlt">CAIs</span> had 10B/11B ratios higher than chondritic correlating with the elemental ratio 9Be/11B, suggestive of in situ decay of this key short-lived radionuclide. The initial (10Be/9Be)0 ratios vary between ~10-3 and ~10-2 for <span class="hlt">CAI</span> 411. The initial ratio of <span class="hlt">CAI</span> 411 is one order of magnitude higher than the highest ratio found in CV3 <span class="hlt">CAIs</span>, suggesting that the more likely origin of <span class="hlt">CAI</span> 411 10Be is early solar system irradiation. The low (26Al/27Al)0 [<= 8.9 × 10-7] with which <span class="hlt">CAI</span> 411 formed indicates that it was exposed to gradual flares with a proton fluence of a few 1019 protons cm-2, during the earliest phases of the solar system, possibly the infrared class 0. The irradiation conditions for other <span class="hlt">CAIs</span> are less well constrained, with calculated fluences ranging between a few 1019 and 1020 protons cm-2. The variable and extreme value of the initial 10Be/9Be ratios in carbonaceous chondrite <span class="hlt">CAIs</span> is the reflection of the variable and extreme magnetic activity in young stars observed in the X-ray domain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993Metic..28Q.335C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993Metic..28Q.335C"><span id="translatedtitle">Thermal Histories of PGE-rich Metal Particles in a Vigarano <span class="hlt">CAI</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Casanova, I.; Grossman, L.</p> <p>1993-07-01</p> <p>Metal particles in Vigarano 1623-8, a Type B2 <span class="hlt">CAI</span> [1], underwent virtually no sulfidation, as is typical of opaque assemblages from Ca, Al-rich inclusions in the reduced CV3 chondrites [2]. In this study, we have identified two large metal grains (M1 and M2) with chemical and mineralogical features that may indicate cooling under different conditions and are, therefore, difficult to understand in the environment of a single <span class="hlt">CAIs</span> thermal evolution. M1 is an almost spherical, kamacite+taenite-bearing particle included in a fassaite grain of the <span class="hlt">CAI</span> host; a 17.5 micrometer-long (0.5 micrometer steps) microprobe traverse along M1 shows that Ni and Ru contents in the taenite (31.5 and 1.1 wt%, respectively) are uniform, and differ from those in the adjacent kamacite (Ni=4.5, Ru=0.7 wt%). M2 is a 20 micrometer, irregularly-shaped taenite particle, embedded in a fine-grained (spinel-rich) portion of 1623-8. It has a homogeneous composition with 10.5 wt% Ni, 0.4% Co, 0.7% Re, 0.6% Pt and high concentrations of Ru (6.5 wt%), Os (4.3 wt%) and Ir (8.2 wt%), as previously recognized by [1]. The composition of M2 is such that it should have undergone exsolution at 800 = T >= 600 degrees C (according to experimental data by [3]) to form at least two (alpha+gamma-NiFe), or probably three (+epsilon-RuFe) different phases. Lack of exsolution features in this large grain is therefore indicative of equilibration at relatively high temperatures (T>600 degrees C) followed by rapid cooling. Other metal particles of similar bulk compositions in <span class="hlt">CAIs</span> from the Leoville chondrite (also a reduced CV3) show extensive exsolution features that have been interpreted as the result of low- temperature equilibration of the <span class="hlt">CAI</span> and their constituents after incorporation into their parent body [4, 5]. The relatively high equilibration temperature of M2 is, however, inconsistent with the existence of kamacite in M1. From the phase relations in the Fe-Ni binary, a grain like M1, with 25 wt% bulk Ni</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/1807767','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/1807767"><span id="translatedtitle">Hypertext and three-dimensional computer graphics in an all digital PC-based <span class="hlt">CAI</span> workstation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schwarz, D L; Wind, G G</p> <p>1991-01-01</p> <p>In the past several years there has been an enormous increase in the number of computer-assisted instructional (<span class="hlt">CAI</span>) applications. Many medical educators and physicians have recognized the power and utility of hypertext. Some developers have incorporated simple diagrams, scanned monochrome graphics or still frame photographs from a laser disc or CD-ROM into their hypertext applications. These technologies have greatly increased the role of the microcomputer in education and training. There still remain numerous applications for these tools which are yet to be explored. One of these exciting areas involves the use of three-dimensional computer graphics. An all digital platform increases application portability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009gdca.conf..321C&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009gdca.conf..321C&link_type=ABSTRACT"><span id="translatedtitle">Problem Solving Process Research of Everyone Involved in Innovation Based on <span class="hlt">CAI</span> Technology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Tao; Shao, Yunfei; Tang, Xiaowo</p> <p></p> <p>It is very important that non-technical department personnel especially bottom line employee serve as innovators under the requirements of everyone involved in innovation. According the view of this paper, it is feasible and necessary to build everyone involved in innovation problem solving process under Total Innovation Management (TIM) based on the Theory of Inventive Problem Solving (TRIZ). The tools under the <span class="hlt">CAI</span> technology: How TO mode and science effects database could be very useful for all employee especially non-technical department and bottom line for innovation. The problem solving process put forward in the paper focus on non-technical department personnel especially bottom line employee for innovation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014E%26PSL.401..327B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014E%26PSL.401..327B"><span id="translatedtitle">An oxygen isotope study of Wark-Lovering rims on type A <span class="hlt">CAIs</span> in primitive carbonaceous chondrites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bodénan, Jean-David; Starkey, Natalie A.; Russell, Sara S.; Wright, Ian P.; Franchi, Ian A.</p> <p>2014-09-01</p> <p>Calcium-aluminium-rich Inclusions (<span class="hlt">CAIs</span>) and the thin Wark-Lovering (WL) rims of minerals surrounding them offer a record of the nature of changing conditions during the earliest stages of Solar System formation. Considerable heterogeneity in the gas composition in the immediate vicinity of the proto-Sun had previously been inferred from oxygen isotopic variations in the WL rim of a <span class="hlt">CAI</span> from Allende (Simon et al., 2011). However, high precision and high spatial resolution oxygen isotope measurements presented in this study show that WL rim and pristine core minerals of individual <span class="hlt">CAIs</span> from meteorites that had experienced only low degrees of alteration or low grade metamorphism (one from Léoville (reduced CV3), two in QUE 99177 (CR3.0) and two in ALHA 77307 (CO3.0)) are uniformly 16O-rich. This indicates that the previously observed variations are the result of secondary processes, most likely on the asteroid parent body, and that there were no temporal or spatial variations in oxygen isotopic composition during <span class="hlt">CAI</span> and WL rim formation. Such homogeneity across three groups of carbonaceous chondrites lends further support for a common origin for the <span class="hlt">CAIs</span> in all chondrites. 16O-poor oxygen reservoirs such as those associated with chondrule formation, were probably generated by UV photo-dissociation involving self-shielding mechanisms and must have occurred elsewhere in outer regions of the solar accretion disk.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/907835','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/907835"><span id="translatedtitle">Constraints on the Origin of Chondrules and <span class="hlt">CAIs</span> from Short-Lived and Long-Lived Radionuclides</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kita, N T; Huss, G R; Tachibana, S; Amelin, Y; Nyquist, L E; Hutcheon, I D</p> <p>2005-10-24</p> <p>The high time resolution Pb-Pb ages and short-lived nuclide based relative ages for <span class="hlt">CAIs</span> and chondrules are reviewed. The solar system started at 4567.2 {+-} 0.6Ma inferred from the high precision Pb-Pb ages of <span class="hlt">CAIs</span>. Time scales of <span class="hlt">CAIs</span> ({le}0.1Myr), chondrules (1-3Myr), and early asteroidal differentiation ({ge}3Myr) inferred from {sup 26}Al relative ages are comparable to the time scale estimated from astronomical observations of young star; proto star, classical T Tauri star and week-lined T Tauri star, respectively. Pb-Pb ages of chondrules also indicate chondrule formation occur within 1-3 Myr after <span class="hlt">CAIs</span>. Mn-Cr isochron ages of chondrules are similar to or within 2 Myr after <span class="hlt">CAI</span> formation. Chondrules from different classes of chondrites show the same range of {sup 26}Al ages in spite of their different oxygen isotopes, indicating that chondrule formed in the localized environment. The {sup 26}Al ages of chondrules in each chondrite class show a hint of correlation with their chemical compositions, which implies the process of elemental fractionation during chondrule formation events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20060047785','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20060047785"><span id="translatedtitle"><span class="hlt">Aerosol</span> Lidar and MODIS Satellite Comparisons for Future <span class="hlt">Aerosol</span> Loading Forecast</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>DeYoung, Russell; Szykman, James; Severance, Kurt; Chu, D. Allen; Rosen, Rebecca; Al-Saadi, Jassim</p> <p>2006-01-01</p> <p>Knowledge of the concentration and distribution of atmospheric <span class="hlt">aerosols</span> using both airborne lidar and satellite instruments is a field of active research. An aircraft based <span class="hlt">aerosol</span> lidar has been used to study the distribution of atmospheric <span class="hlt">aerosols</span> in the California Central Valley and eastern US coast. Concurrently, satellite <span class="hlt">aerosol</span> retrievals, from the MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) instrument aboard the Terra and Aqua satellites, were take over the Central Valley. The MODIS Level 2 <span class="hlt">aerosol</span> data product provides retrieved ambient <span class="hlt">aerosol</span> optical properties (e.g., optical depth (AOD) and size distribution) globally over ocean and land at a spatial resolution of 10 km. The Central Valley topography was overlaid with MODIS AOD (5x5 sq km resolution) and the <span class="hlt">aerosol</span> scattering vertical profiles from a lidar flight. Backward air parcel trajectories for the lidar data show that air from the Pacific and northern part of the Central Valley converge confining the <span class="hlt">aerosols</span> to the lower valley region and below the mixed layer. Below an altitude of 1 km, the lidar <span class="hlt">aerosol</span> and MODIS AOD exhibit good agreement. Both data sets indicate a high presence of <span class="hlt">aerosols</span> near Bakersfield and the Tehachapi Mountains. These and other results to be presented indicate that the majority of the <span class="hlt">aerosols</span> are below the mixed layer such that the MODIS AOD should correspond well with surface measurements. Lidar measurements will help interpret satellite AOD retrievals so that one day they can be used on a routine basis for prediction of boundary layer <span class="hlt">aerosol</span> pollution events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030102194','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030102194"><span id="translatedtitle">The MODIS <span class="hlt">Aerosol</span> Algorithm, Products and Validation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Remer, L. A.; Kaufman, Y. J.; Tanre, D.; Mattoo, S.; Chu, D. A.; Martins, J. V.; Li, R.-R.; Ichoku, C.; Levy, R. C.; Kleidman, R. G.</p> <p>2003-01-01</p> <p>The MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) aboard both NASA's Terra and Aqua satellites is making near global daily observations of the earth in a wide spectral range. These measurements are used to derive spectral <span class="hlt">aerosol</span> optical thickness and <span class="hlt">aerosol</span> size parameters over both land and ocean. The <span class="hlt">aerosol</span> products available over land include <span class="hlt">aerosol</span> optical thickness at three visible wavelengths, a measure of the fraction of <span class="hlt">aerosol</span> optical thickness attributed to the fine mode and several derived parameters including reflected spectral solar flux at top of atmosphere. Over ocean, the <span class="hlt">aerosol</span> optical thickness is provided in seven wavelengths from 0.47 microns to 2.13 microns. In addition, quantitative <span class="hlt">aerosol</span> size information includes effective radius of the <span class="hlt">aerosol</span> and quantitative fraction of optical thickness attributed to the fine mode. Spectral <span class="hlt">aerosol</span> flux, mass concentration and number of cloud condensation nuclei round out the list of available <span class="hlt">aerosol</span> products over the ocean. The spectral optical thickness and effective radius of the <span class="hlt">aerosol</span> over the ocean are validated by comparison with two years of AERONET data gleaned from 133 AERONET stations. 8000 MODIS <span class="hlt">aerosol</span> retrievals colocated with AERONET measurements confirm that one-standard deviation of MODIS optical thickness retrievals fall within the predicted uncertainty of delta tauapproximately equal to plus or minus 0.03 plus or minus 0.05 tau over ocean and delta tay equal to plus or minus 0.05 plus or minus 0.15 tau over land. 271 MODIS <span class="hlt">aerosol</span> retrievals co-located with AERONET inversions at island and coastal sites suggest that one-standard deviation of MODIS effective radius retrievals falls within delta r_eff approximately equal to 0.11 microns. The accuracy of the MODIS retrievals suggests that the product can be used to help narrow the uncertainties associated with <span class="hlt">aerosol</span> radiative forcing of global climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/9757487','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/9757487"><span id="translatedtitle">[<span class="hlt">Aerosol</span> therapy].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wildhaber, J H</p> <p>1998-08-15</p> <p><span class="hlt">Aerosol</span> therapy plays a major role in the diagnosis and treatment of various lung diseases. The aim of inhalation therapy is to deposit a reproducible and adequate dose of a specific drug to the airways, in order to achieve a high, local, clinical effect while avoiding serious systemic side effects. To achieve this goal, it is therefore important to have an efficient inhalation device to deliver different medications. However, the currently available therapeutic inhalation devices (nebuliser, pressurised metered-dose inhaler and dry powder inhaler) are not very efficient in <span class="hlt">aerosol</span> delivery and have several disadvantages. Inhalation devices can be assessed by in vitro studies, filter studies and radiolabelled deposition studies. Several radiolabelled deposition studies have shown that nebulisers and pressurised metered-dose inhalers are not very efficient in <span class="hlt">aerosol</span> delivery. In children, before 1997, only 0.5% to 15% of the total nebulised or actuated dose from a nebuliser or pressurised metered-dose inhaler actually reached the lungs. These numbers were somewhat improved in adults, 30% of the total nebulised or actuated dose reaching the airways. <span class="hlt">Aerosol</span> therapy with dry powder inhalers was the most efficient before 1997, 30% of the total dose being deposited in the lungs of adults and children. In 1997, new developments in pressurised metered-dose inhalers much improved their efficiency in <span class="hlt">aerosol</span> delivery. Lung deposition can be increased by up to 60% with use of a non-electrostatic holding chamber and/or a pressurised metered-dose inhaler with a hydrofluoroalkane propellant possessing superior <span class="hlt">aerosol</span> characteristics. Several studies comparing the clinical efficiency of different inhalation devices have shown that the choice of an optimal inhalation device is crucial. In addition to the <span class="hlt">aerosol</span> characteristics, ventilation parameters and airway morphology have an important bearing on deposition patterns. These parameters may be greatly influenced by the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140012818','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140012818"><span id="translatedtitle">In Situ Trace Element Analysis of an Allende Type B1 <span class="hlt">CAI</span>: EK-459-5-1</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jeffcoat, C. R.; Kerekgyarto, A.; Lapen, T. J.; Andreasen, R.; Righter, M.; Ross, D. K.</p> <p>2014-01-01</p> <p>Variations in refractory major and trace element composition of calcium, aluminum-rich inclusions (<span class="hlt">CAIs</span>) provide constraints on physical and chemical conditions and processes in the earliest stages of the Solar System. Previous work indicates that <span class="hlt">CAIs</span> have experienced complex histories involving, in many cases, multiple episodes of condensation, evaporation, and partial melting. We have analyzed major and trace element abundances in two core to rim transects of the melilite mantle as well as interior major phases of a Type B1 <span class="hlt">CAI</span> (EK-459-5-1) from Allende by electron probe micro-analyzer (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to investigate the behavior of key trace elements with a primary focus on the REEs Tm and Yb.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890006945','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890006945"><span id="translatedtitle">Extending the granularity of representation and control for the MIL-STD <span class="hlt">CAIS</span> 1.0 node model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rogers, Kathy L.</p> <p>1986-01-01</p> <p>The Common APSE (Ada 1 Program Support Environment) Interface Set (<span class="hlt">CAIS</span>) (DoD85) node model provides an excellent baseline for interfaces in a single-host development environment. To encompass the entire spectrum of computing, however, the <span class="hlt">CAIS</span> model should be extended in four areas. It should provide the interface between the engineering workstation and the host system throughout the entire lifecycle of the system. It should provide a basis for communication and integration functions needed by distributed host environments. It should provide common interfaces for communications mechanisms to and among target processors. It should provide facilities for integration, validation, and verification of test beds extending to distributed systems on geographically separate processors with heterogeneous instruction set architectures (ISAS). Additions to the PROCESS NODE model to extend the <span class="hlt">CAIS</span> into these four areas are proposed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21390725','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21390725"><span id="translatedtitle">An experimental study of fuel injection strategies in <span class="hlt">CAI</span> gasoline engine</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hunicz, J.; Kordos, P.</p> <p>2011-01-15</p> <p>Combustion of gasoline in a direct injection controlled auto-ignition (<span class="hlt">CAI</span>) single-cylinder research engine was studied. <span class="hlt">CAI</span> operation was achieved with the use of the negative valve overlap (NVO) technique and internal exhaust gas re-circulation (EGR). Experiments were performed at single injection and split injection, where some amount of fuel was injected close to top dead centre (TDC) during NVO interval, and the second injection was applied with variable timing. Additionally, combustion at variable fuel-rail pressure was examined. Investigation showed that at fuel injection into recompressed exhaust fuel reforming took place. This process was identified via an analysis of the exhaust-fuel mixture composition after NVO interval. It was found that at single fuel injection in NVO phase, its advance determined the heat release rate and auto-ignition timing, and had a strong influence on NO{sub X} emission. However, a delay of single injection to intake stroke resulted in deterioration of cycle-to-cycle variability. Application of split injection showed benefits of this strategy versus single injection. Examinations of different fuel mass split ratios and variable second injection timing resulted in further optimisation of mixture formation. At equal share of the fuel mass injected in the first injection during NVO and in the second injection at the beginning of compression, the lowest emission level and cyclic variability improvement were observed. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9731333','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9731333"><span id="translatedtitle">Using <span class="hlt">CAI</span> to accommodate a variety of learning styles in a biomechanics course.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Washington, N; Parnianpour, M</p> <p>1997-01-01</p> <p>Multimedia technology offers a more interactive approach to instruction than the traditional classroom lectures. Through computer-aided instruction (<span class="hlt">CAI</span>), a number of teaching styles can be used that take into account the different preferences of the students. The Biomechanics Tutorial program that the authors have written is a <span class="hlt">CAI</span> that incorporates audio, video, simulations, and graphics to: review concepts of mechanics (kinematics and kinetics of interconnected rigid bodies), familiarize students with functional anatomy, and allow students to interactively evaluate the law of mechanics applied to physical performance of activities modeled by a set of biomechanical models of the joints. Principles of ergonomics are reinforced by enabling the student to perform numerous numerical experiments within the context of workplace or task redesign and see the real time consequences of these alterations. For example, the task of holding a load is simulated by allowing the student to change elbow and shoulder angles and the orientation and magnitude of the load. The consequences of these in terms of required muscle forces and joint reaction forces at the elbow and shoulder will be updated on the screen. The detailed rationale of developing this Biomechanics Tutorial which integrates a variety of learning styles will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120001852','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120001852"><span id="translatedtitle">Ca-Fe and Alkali-Halide Alteration of an Allende Type B <span class="hlt">CAI</span>: Aqueous Alteration in Nebular or Asteroidal Settings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ross, D. K.; Simon, J. I.; Simon, S. B.; Grossman, L.</p> <p>2012-01-01</p> <p>Ca-Fe and alkali-halide alteration of <span class="hlt">CAIs</span> is often attributed to aqueous alteration by fluids circulating on asteroidal parent bodies after the various chondritic components have been assembled, although debate continues about the roles of asteroidal vs. nebular modification processes [1-7]. Here we report de-tailed observations of alteration products in a large Type B2 <span class="hlt">CAI</span>, TS4 from Allende, one of the oxidized subgroup of CV3s, and propose a speculative model for aqueous alteration of <span class="hlt">CAIs</span> in a nebular setting. Ca-Fe alteration in this <span class="hlt">CAI</span> consists predominantly of end-member hedenbergite, end-member andradite, and compositionally variable, magnesian high-Ca pyroxene. These phases are strongly concentrated in an unusual "nodule" enclosed within the interior of the <span class="hlt">CAI</span> (Fig. 1). The Ca, Fe-rich nodule superficially resembles a clast that pre-dated and was engulfed by the <span class="hlt">CAI</span>, but closer inspection shows that relic spinel grains are enclosed in the nodule, and corroded <span class="hlt">CAI</span> primary phases interfinger with the Fe-rich phases at the nodule s margins. This <span class="hlt">CAI</span> also contains abundant sodalite and nepheline (alkali-halide) alteration that occurs around the rims of the <span class="hlt">CAI</span>, but also penetrates more deeply into the <span class="hlt">CAI</span>. The two types of alteration (Ca-Fe and alkali-halide) are adjacent, and very fine-grained Fe-rich phases are associated with sodalite-rich regions. Both types of alteration appear to be replacive; if that is true, it would require substantial introduction of Fe, and transport of elements (Ti, Al and Mg) out of the nodule, and introduction of Na and Cl into alkali-halide rich zones. Parts of the <span class="hlt">CAI</span> have been extensively metasomatized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020008210','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020008210"><span id="translatedtitle">Validation of MODIS <span class="hlt">Aerosol</span> Retrieval Over Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Remer, Lorraine A.; Tanre, Didier; Kaufman, Yoram J.; Ichoku, Charles; Mattoo, Shana; Levy, Robert; Chu, D. Allen; Holben, Brent N.; Dubovik, Oleg; Ahmad, Ziauddin; Einaudi, Franco (Technical Monitor)</p> <p>2001-01-01</p> <p>The MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) algorithm for determining <span class="hlt">aerosol</span> characteristics over ocean is performing with remarkable accuracy. A two-month data set of MODIS retrievals co-located with observations from the <span class="hlt">AErosol</span> RObotic NETwork (AERONET) ground-based sunphotometer network provides the necessary validation. Spectral radiation measured by MODIS (in the range 550 - 2100 nm) is used to retrieve the <span class="hlt">aerosol</span> optical thickness, effective particle radius and ratio between the submicron and micron size particles. MODIS-retrieved <span class="hlt">aerosol</span> optical thickness at 660 nm and 870 nm fall within the expected uncertainty, with the ensemble average at 660 nm differing by only 2% from the AERONET observations and having virtually no offset. MODIS retrievals of <span class="hlt">aerosol</span> effective radius agree with AERONET retrievals to within +/- 0.10 micrometers, while MODIS-derived ratios between large and small mode <span class="hlt">aerosol</span> show definite correlation with ratios derived from AERONET data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACP....15.5743B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACP....15.5743B"><span id="translatedtitle">Using the OMI <span class="hlt">aerosol</span> index and absorption <span class="hlt">aerosol</span> optical depth to evaluate the NASA MERRA <span class="hlt">Aerosol</span> Reanalysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buchard, V.; da Silva, A. M.; Colarco, P. R.; Darmenov, A.; Randles, C. A.; Govindaraju, R.; Torres, O.; Campbell, J.; Spurr, R.</p> <p>2015-05-01</p> <p>A radiative transfer interface has been developed to simulate the UV <span class="hlt">aerosol</span> index (AI) from the NASA Goddard Earth Observing System version 5 (GEOS-5) <span class="hlt">aerosol</span> assimilated fields. The purpose of this work is to use the AI and <span class="hlt">aerosol</span> absorption optical depth (AAOD) derived from the Ozone Monitoring Instrument (OMI) measurements as independent validation for the Modern Era Retrospective analysis for Research and Applications <span class="hlt">Aerosol</span> Reanalysis (MERRAero). MERRAero is based on a version of the GEOS-5 model that is radiatively coupled to the Goddard Chemistry, <span class="hlt">Aerosol</span>, Radiation, and Transport (GOCART) <span class="hlt">aerosol</span> module and includes assimilation of <span class="hlt">aerosol</span> optical depth (AOD) from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) sensor. Since AI is dependent on <span class="hlt">aerosol</span> concentration, optical properties and altitude of the <span class="hlt">aerosol</span> layer, we make use of complementary observations to fully diagnose the model, including AOD from the Multi-angle <span class="hlt">Imaging</span> SpectroRadiometer (MISR), <span class="hlt">aerosol</span> retrievals from the <span class="hlt">AErosol</span> RObotic NETwork (AERONET) and attenuated backscatter coefficients from the Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) mission to ascertain potential misplacement of plume height by the model. By sampling dust, biomass burning and pollution events in 2007 we have compared model-produced AI and AAOD with the corresponding OMI products, identifying regions where the model representation of absorbing <span class="hlt">aerosols</span> was deficient. As a result of this study over the Saharan dust region, we have obtained a new set of dust <span class="hlt">aerosol</span> optical properties that retains consistency with the MODIS AOD data that were assimilated, while resulting in better agreement with <span class="hlt">aerosol</span> absorption measurements from OMI. The analysis conducted over the southern African and South American biomass burning regions indicates that revising the spectrally dependent <span class="hlt">aerosol</span> absorption properties in the near-UV region improves the modeled-observed AI comparisons</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010679','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010679"><span id="translatedtitle">Microstructures of Hibonite From an ALH A77307 (CO3.0) <span class="hlt">CAI</span>: Evidence for Evaporative Loss of Calcium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Han, Jangmi; Brearley, Adrian J.; Keller, Lindsay P.</p> <p>2014-01-01</p> <p>Hibonite is a comparatively rare, primary phase found in some <span class="hlt">CAIs</span> from different chondrite groups and is also common in Wark-Lovering rims [1]. Hibonite is predicted to be one of the earliest refractory phases to form by equilibrium condensation from a cooling gas of solar composition [2] and, therefore, can be a potential recorder of very early solar system processes. In this study, we describe the microstructures of hibonite from one <span class="hlt">CAI</span> in ALH A77307 (CO3.0) using FIB/TEM techniques in order to reconstruct its formational history.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160002651','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160002651"><span id="translatedtitle">Calcium and Titanium Isotope Fractionation in <span class="hlt">CAIS</span>: Tracers of Condensation and Inheritance in the Early Solar Protoplanetary Disk</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Simon, J. I.; Jordan, M. K.; Tappa, M. J.; Kohl, I. E.; Young, E. D.</p> <p>2016-01-01</p> <p>The chemical and isotopic compositions of calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>) can be used to understand the conditions present in the protoplantary disk where they formed. The isotopic compositions of these early-formed nebular materials are largely controlled by chemical volatility. The isotopic effects of evaporation/sublimation, which are well explained by both theory and experimental work, lead to enrichments of the heavy isotopes that are often exhibited by the moderately refractory elements Mg and Si. Less well understood are the isotopic effects of condensation, which limits our ability to determine whether a <span class="hlt">CAI</span> is a primary condensate and/or retains any evidence of its primordial formation history.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACP....1510597P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACP....1510597P"><span id="translatedtitle">A global <span class="hlt">aerosol</span> classification algorithm incorporating multiple satellite data sets of <span class="hlt">aerosol</span> and trace gas abundances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Penning de Vries, M. J. M.; Beirle, S.; Hörmann, C.; Kaiser, J. W.; Stammes, P.; Tilstra, L. G.; Tuinder, O. N. E.; Wagner, T.</p> <p>2015-09-01</p> <p>Detecting the optical properties of <span class="hlt">aerosols</span> using passive satellite-borne measurements alone is a difficult task due to the broadband effect of <span class="hlt">aerosols</span> on the measured spectra and the influences of surface and cloud reflection. We present another approach to determine <span class="hlt">aerosol</span> type, namely by studying the relationship of <span class="hlt">aerosol</span> optical depth (AOD) with trace gas abundance, <span class="hlt">aerosol</span> absorption, and mean <span class="hlt">aerosol</span> size. Our new Global <span class="hlt">Aerosol</span> Classification Algorithm, GACA, examines relationships between <span class="hlt">aerosol</span> properties (AOD and extinction Ångström exponent from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), UV <span class="hlt">Aerosol</span> Index from the second Global Ozone Monitoring Experiment, GOME-2) and trace gas column densities (NO2, HCHO, SO2 from GOME-2, and CO from MOPITT, the Measurements of Pollution in the Troposphere instrument) on a monthly mean basis. First, <span class="hlt">aerosol</span> types are separated based on size (Ångström exponent) and absorption (UV <span class="hlt">Aerosol</span> Index), then the dominating sources are identified based on mean trace gas columns and their correlation with AOD. In this way, global maps of dominant <span class="hlt">aerosol</span> type and main source type are constructed for each season and compared with maps of <span class="hlt">aerosol</span> composition from the global MACC (Monitoring Atmospheric Composition and Climate) model. Although GACA cannot correctly characterize transported or mixed <span class="hlt">aerosols</span>, GACA and MACC show good agreement regarding the global seasonal cycle, particularly for urban/industrial <span class="hlt">aerosols</span>. The seasonal cycles of both <span class="hlt">aerosol</span> type and source are also studied in more detail for selected 5° × 5° regions. Again, good agreement between GACA and MACC is found for all regions, but some systematic differences become apparent: the variability of <span class="hlt">aerosol</span> composition (yearly and/or seasonal) is often not well captured by MACC, the amount of mineral dust outside of the dust belt appears to be overestimated, and the abundance of secondary organic <span class="hlt">aerosols</span> is underestimated in comparison</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=GL-2002-002141&hterms=ocean+pollution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Docean%2Bpollution','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=GL-2002-002141&hterms=ocean+pollution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Docean%2Bpollution"><span id="translatedtitle">Effects of <span class="hlt">Aerosols</span> over the Indian Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p><span class="hlt">Aerosols</span> that contain black carbon both absorb and reflect incoming sunlight. Even as these atmospheric particles reduce the amount of sunlight reaching the surface, they increase the amount of solar energy absorbed in the atmosphere, thus making it possible to both cool the surface and warm the atmosphere. The <span class="hlt">images</span> above show satellite measurements of the region studied during the Indian Ocean Experiment (INDOEX)a vast region spanning the Arabian Sea and Bay of Bengal (west to east), and from the foot of the Himalayan Mountains, across the Indian subcontinent to the southern Indian Ocean (north to south). The <span class="hlt">Aerosol</span> <span class="hlt">images</span> show <span class="hlt">aerosol</span> pollution (brownish pixels) in the lower atmosphere over the INDOEX study area, as measured by the Moderate-resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) aboard Terra. These were composited from March 14-21, 2001. The Albedo <span class="hlt">images</span> show the total solar energy reflected back to space, as measured by Clouds and Earth's Radiant Energy System (CERES) aboard Terra. White pixels show high values, greens are intermediate values, and blues are low. Note how the <span class="hlt">aerosols</span>, particularly over the ocean, increase the amount of energy reflected back to space. The Atmospheric Warming <span class="hlt">images</span> show the absorption of the black carbon <span class="hlt">aerosols</span> in the atmosphere. Where the <span class="hlt">aerosols</span> are most dense, the absorption is highest. Red pixels indicate the highest levels of absorption, blues are low. The Surface Cooling <span class="hlt">images</span> show that the <span class="hlt">aerosol</span> particles reduce the amount of sunlight reaching the surface. Dark pixels show where the <span class="hlt">aerosols</span> exert their cooling influence on the surface (or a high magnitude of negative radiative forcing). The bright pixels show where there is much less <span class="hlt">aerosol</span> pollution and the incoming sunlight is relatively unaffected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED503459.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED503459.pdf"><span id="translatedtitle">A Comparative Study to Evaluate the Effectiveness of Computer Assisted Instruction (<span class="hlt">CAI</span>) versus Class Room Lecture (RL) for Computer Science at ICS Level</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Kausar, Tayyaba; Choudhry, Bushra Naoreen; Gujjar, Aijaz Ahmed</p> <p>2008-01-01</p> <p>This study was aimed to evaluate the effectiveness of <span class="hlt">CAI</span> vs. classroom lecture for computer science at ICS level. The objectives were to compare the learning effects of two groups with class room lecture and computer assisted instruction studying the same curriculum and the effects of <span class="hlt">CAI</span> and CRL in terms of cognitive development. Hypothesis of…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1102933.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1102933.pdf"><span id="translatedtitle">A Comparative Study to Evaluate the Effectiveness of Computer Assisted Instruction (<span class="hlt">CAI</span>) versus Class Room Lecture (CRL) for Computer Science at ICS Level</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Kausar, Tayyaba; Choudhry, Bushra Naoreen; Gujjar, Aijaz Ahmed</p> <p>2008-01-01</p> <p>This study was aimed to evaluate the effectiveness of <span class="hlt">CAI</span> vs. classroom lecture for computer science at ICS level. The objectives were to compare the learning effects of two groups with class room lecture and computer assisted instruction studying the same curriculum and the effects of <span class="hlt">CAI</span> and CRL in terms of cognitive development. Hypothesis of…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17119596','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17119596"><span id="translatedtitle"><span class="hlt">Aerosol</span> polarization effects on atmospheric correction and <span class="hlt">aerosol</span> retrievals in ocean color remote sensing.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Menghua</p> <p>2006-12-10</p> <p>The current ocean color data processing system for the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) and the moderate resolution <span class="hlt">imaging</span> spectroradiometer (MODIS) uses the Rayleigh lookup tables that were generated using the vector radiative transfer theory with inclusion of the polarization effects. The polarization effects, however, are not accounted for in the <span class="hlt">aerosol</span> lookup tables for the ocean color data processing. I describe a study of the <span class="hlt">aerosol</span> polarization effects on the atmospheric correction and <span class="hlt">aerosol</span> retrieval algorithms in the ocean color remote sensing. Using an efficient method for the multiple vector radiative transfer computations, <span class="hlt">aerosol</span> lookup tables that include polarization effects are generated. Simulations have been carried out to evaluate the <span class="hlt">aerosol</span> polarization effects on the derived ocean color and <span class="hlt">aerosol</span> products for all possible solar-sensor geometries and the various <span class="hlt">aerosol</span> optical properties. Furthermore, the new <span class="hlt">aerosol</span> lookup tables have been implemented in the SeaWiFS data processing system and extensively tested and evaluated with SeaWiFS regional and global measurements. Results show that in open oceans (maritime environment), the <span class="hlt">aerosol</span> polarization effects on the ocean color and <span class="hlt">aerosol</span> products are usually negligible, while there are some noticeable effects on the derived products in the coastal regions with nonmaritime <span class="hlt">aerosols</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9882E..08P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9882E..08P"><span id="translatedtitle">Genesis of elevated <span class="hlt">aerosol</span> loading over the Indian region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Prijith, S. S.; Rao, P. V. N.; Mohan, Mannil</p> <p>2016-05-01</p> <p>Elevated <span class="hlt">aerosols</span> assume importance as the diabatic heating due to <span class="hlt">aerosol</span> absorption is more intense at higher altitudes where the atmosphere becomes thinner. Indian region, especially its central and northern latitudes, experiences significant loading of elevated <span class="hlt">aerosols</span> during pre-monsoon and summer months. Genesis of elevated <span class="hlt">aerosol</span> loading over Indian region is investigated in the present study, using multi-year satellite observations from Cloud <span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization (CALIOP) and Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) along with reanalysis winds from MERRA. Central India is observed to have prominent <span class="hlt">aerosols</span> loading at higher altitudes during pre-monsoon season, whereas it is during summer months over north-west India. Further analysis reveals that the elevated <span class="hlt">aerosols</span> over Indian region in pre-monsoon and summer months are significantly contributed by transported mineral dust from the arid continental regions at west. In addition to the mineral dust advection, <span class="hlt">aerosols</span> at higher altitudes over Indian region are enriched by strong convection and associated vertical transport of surface level <span class="hlt">aerosols</span>. Vertical transport of <span class="hlt">aerosols</span> observed over Indian region during pre-monsoon and summer months is aided by intense convergence at the surface level and divergence at the upper level. Moreover, <span class="hlt">aerosol</span> source/sink strength estimated using <span class="hlt">aerosol</span> flux continuity equation show significant <span class="hlt">aerosol</span> production over central India during pre-monsoon. Strong vertical transport prevails during pre-monsoon uplifts the locally produced <span class="hlt">aerosols</span>, with considerable anthropogenic fraction, to higher altitudes where their impacts would be more intense.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016DPS....4850505D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016DPS....4850505D"><span id="translatedtitle">Linking <span class="hlt">CAI</span> abundance to polarimetric response in a population of ancient asteroids</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Devogele, Maxime; Tanga, Paolo; Bendjoya, Philippe; Rivet, Jean-Pierre; Surdej, Jean; Bus, Schelte J.; Sunshine, Jessica M.; Cellino, Alberto; Campins, Humberto; Licandro, Javier; Pinilla-Alonso, Noemi; Carry, Benoit</p> <p>2016-10-01</p> <p>Polarimetry constitutes one of the fundamental tools for characterizing the surface texture and composition of airless Solar System bodies. In 2006, polarimetric observations led to the discovery of a new type of asteroids, which displays a peculiar polarimetric response. These asteroids are collectively known as "Barbarians", from (234) Barbara the first discovered one.The most commonly accepted explanation for this perculiar polarization response seems to be the presence of a high percentage of fluffy-type Calcium Aluminium-rich Inclusions (<span class="hlt">CAIs</span>), whose optical properties could produce the observed polarization. Their reflectance spectra also exibit an absorption feature in the near-infrared around 2.1-2.2 microns, that is characteristic of this peculiar group.Based on these results, we organized a systematic polarimetric and near-infrared observational campaign of known Barbarians or candidate asteroids. These campaigns include members of the family of 1040 Klumpkea, 2085 Henan and 729 Watsonia, which are known to contain Barbarian and/or L-type asteroids also suspected to have such a polarimetric behaviour. We have made use of the ToPo polarimeter at the 1m telescope of the Centre pédagogique Planète et Univers (C2PU, Observatoire de la Côte d'Azur, France). The spectroscopic observations in the near-infrared were obtained with the SpeX instrument at the NASA's InfraRed Telescope Facility (IRTF).By combining polarimetry and spectroscopy we find a correlation between the abundance of <span class="hlt">CAIs</span> and the inversion angle of the phase-polarization curve of Barbarian asteroids. This is the first time that a direct link has been established between a specific polarimetric response and the surface composition of asteroids. In addition, we find a considerable variety of <span class="hlt">CAI</span> abundance from one object to the other, consistent with a wide range of possible albedos. Since these asteroids constitute a reservoir of primitive Solar System material, understanding their origin can</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930046612&hterms=zones+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dzones%2Bocean','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930046612&hterms=zones+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dzones%2Bocean"><span id="translatedtitle">Comment on '<span class="hlt">Aerosol</span> and Rayleigh radiance contributions to Coastal Zone Colour Scanner <span class="hlt">images</span>' by Eckstein and Simpson</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gordon, H. R.; Evans, R. H.</p> <p>1993-01-01</p> <p>In a recent paper Eckstein and Simpson describe what they believe to be serious difficulties and/or errors with the CZCS (Coastal Zone Color Scanner) processing algorithms based on their analysis of seven <span class="hlt">images</span>. Here we point out that portions of their analysis, particularly those dealing with multiple scattered Rayleigh radiance, are incorrect. We also argue that other problems they discuss have already been addressed in the literature. Finally, we suggest that many apparent artifacts in CZCS-derived pigment fields are likely to be due to inadequacies in the sensor band set or to poor radiometric stability, both of which will be remedied with the next generation of ocean color sensors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=GL-2002-001714&hterms=Confluence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DConfluence','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=GL-2002-001714&hterms=Confluence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DConfluence"><span id="translatedtitle"><span class="hlt">Aerosols</span> over Eastern Asia</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p>This Sea-viewing Wide Field-of-view Sensor (SeaWiFS) <span class="hlt">image</span> of eastern Asia from October 14, 2001, shows large amounts of <span class="hlt">aerosol</span> in the air. A few possible point sources of smoke, probably fires, are visible north of the Amur River at the very top of the <span class="hlt">image</span>. One of the larger of these plumes can be seen down river of the confluence of the Songhua and Amur rivers. At lower left, the Yangtze River plume in the East China Sea is also very prominent. Sediment suspended in the ocean water is quite brown near the shore, but becomes much greener as it diffuses into the water. The increasing greenness of the river plume is probably an indication of enhanced phytoplankton growth driven by the nutrients in the river runoff. <span class="hlt">Image</span> courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=csr&pg=2&id=EJ1062828','ERIC'); return false;" href="http://eric.ed.gov/?q=csr&pg=2&id=EJ1062828"><span id="translatedtitle">From Corporate Social Responsibility, through Entrepreneurial Orientation, to Knowledge Sharing: A Study in <span class="hlt">Cai</span> Luong (Renovated Theatre) Theatre Companies</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Tuan, Luu Trong</p> <p>2015-01-01</p> <p>Purpose: This paper aims to examine the role of antecedents such as corporate social responsibility (CSR) and entrepreneurial orientation in the chain effect to knowledge sharing among members of <span class="hlt">Cai</span> Luong theatre companies in the Vietnamese context. Knowledge sharing contributes to the depth of the knowledge pool of both the individuals and the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED077195.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED077195.pdf"><span id="translatedtitle">A Model Driven Question-Answering System for a <span class="hlt">CAI</span> Environment. Final Report (July 1970 to May 1972).</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Brown, John S.; And Others</p> <p></p> <p>A question answering system which permits a computer-assisted instruction (<span class="hlt">CAI</span>) student greater initiative in the variety of questions he can ask is described. A method is presented to represent the dynamic processes of a subject matter area by augmented finite state automata, which permits efficient inferencing about dynamic processes and…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26832141','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26832141"><span id="translatedtitle">Phenotypic diversity and correlation between white-opaque switching and the <span class="hlt">CAI</span> microsatellite locus in Candida albicans.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hu, Jian; Guan, Guobo; Dai, Yu; Tao, Li; Zhang, Jianzhong; Li, Houmin; Huang, Guanghua</p> <p>2016-08-01</p> <p>Candida albicans is a commensal fungal pathogen that is often found as part of the human microbial flora. The aim of the present study was to establish a relationship between diverse genotypes and phenotypes of clinical isolates of C. albicans. Totally 231 clinical isolates were collected and used for genotyping and phenotypic switching analysis. Based on the microsatellite locus (<span class="hlt">CAI</span>) genotyping assay, 65 different genotypes were identified, and some dominant types were found in certain human niches. For example, the genotypes of 30-44 and 30-45 were enriched in vaginal infection samples. C. albicans has a number of morphological forms including the single-celled yeasts, multicellular filaments, white, and opaque cell types. The relationship between the <span class="hlt">CAI</span> genotype and the ability to undergo phenotypic switching was examined in the clinical isolates. We found that the strains with longer CAA/G repeats in both alleles of the <span class="hlt">CAI</span> locus were more opaque competent. We also discovered that some MTL heterozygous (a/alpha) isolates could undergo white-opaque switching when grown on regular culture medium (containing glucose as the sole carbon source). Our study establishes a link between phenotypic switching and genotypes of the <span class="hlt">CAI</span> microsatellite locus in clinical isolates of C. albicans. PMID:26832141</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2784433','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2784433"><span id="translatedtitle">Hunting and use of terrestrial fauna used by <span class="hlt">Cai</span>çaras from the Atlantic Forest coast (Brazil)</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2009-01-01</p> <p>Background The Brazilian Atlantic Forest is considered one of the hotspots for conservation, comprising remnants of rain forest along the eastern Brazilian coast. Its native inhabitants in the Southeastern coast include the <span class="hlt">Cai</span>çaras (descendants from Amerindians and European colonizers), with a deep knowledge on the natural resources used for their livelihood. Methods We studied the use of the terrestrial fauna in three <span class="hlt">Cai</span>çara communities, through open-ended interviews with 116 native residents. Data were checked through systematic observations and collection of zoological material. Results The dependence on the terrestrial fauna by <span class="hlt">Cai</span>çaras is especially for food and medicine. The main species used are Didelphis spp., Dasyprocta azarae, Dasypus novemcinctus, and small birds (several species of Turdidae). Contrasting with a high dependency on terrestrial fauna resources by native Amazonians, the <span class="hlt">Cai</span>çaras do not show a constant dependency on these resources. Nevertheless, the occasional hunting of native animals represents a complimentary source of animal protein. Conclusion Indigenous or local knowledge on native resources is important in order to promote local development in a sustainable way, and can help to conserve biodiversity, particularly if the resource is sporadically used and not commercially exploited. PMID:19930595</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26159472','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26159472"><span id="translatedtitle">Changes in flavour and microbial diversity during natural fermentation of suan-<span class="hlt">cai</span>, a traditional food made in Northeast China.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wu, Rina; Yu, Meiling; Liu, Xiaoyu; Meng, Lingshuai; Wang, Qianqian; Xue, Yating; Wu, Junrui; Yue, Xiqing</p> <p>2015-10-15</p> <p>We measured changes in the main physical and chemical properties, flavour compounds and microbial diversity in suan-<span class="hlt">cai</span> during natural fermentation. The results showed that the pH and concentration of soluble protein initially decreased but were then maintained at a stable level; the concentration of nitrite increased in the initial fermentation stage and after reaching a peak it decreased significantly to a low level by the end of fermentation. Suan-<span class="hlt">cai</span> was rich in 17 free amino acids. All of the free amino acids increased in concentration to different degrees, except histidine. Total free amino acids reached their highest levels in the mid-fermentation stage. The 17 volatile flavour components identified at the start of fermentation increased to 57 by the mid-fermentation stage; esters and aldehydes were in the greatest diversity and abundance, contributing most to the aroma of suan-<span class="hlt">cai</span>. Bacteria were more abundant and diverse than fungi in suan-<span class="hlt">cai</span>; 14 bacterial species were identified from the genera Leuconostoc, Bacillus, Pseudomonas and Lactobacillus. The predominant fungal species identified were Debaryomyces hansenii, Candida tropicalis and Penicillium expansum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010652','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010652"><span id="translatedtitle">A FIB/TEM/Nanosims Study of a Wark-Lovering Rim on an Allende <span class="hlt">CAI</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keller, L. P.; Needham, A. W.; Messenger, S.</p> <p>2014-01-01</p> <p>Ca- Al-rich inclusions (<span class="hlt">CAIs</span>) are commonly surrounded by Wark-Lovering (WL) rims - thin (approx. 50 micrometers) multilayered sequences - whose mineralogy is dominated by high temperature minerals similar to those that occur in the cores of <span class="hlt">CAIs</span> [1]. The origins of these WL rims involved high temperature events in the early nebula such as condensation, flashheating or reaction with a nebular reservoir, or combinations of these processes. These rims formed after <span class="hlt">CAI</span> formation but prior to accretion into their parent bodies. We have undertaken a coordinated mineralogical and isotopic study of WL rims to determine the formation conditions of the individual layers and to constrain the isotopic reservoirs they interacted with during their history. We focus here on the spinel layer, the first-formed highest- temperature layer in the WL rim sequence. Results and Discussion: We have performed mineralogical, chemical and isotopic analyses of an unusual ultrarefractory inclusion from the Allende CV3 chondrite (SHAL) consisting of an approx. 500 micrometers long single crystal of hibonite and co-existing coarsegrained perovskite. SHAL is partially surrounded by WL rim. We previously reported on the mineralogy, isotopic compositions and trace elements in SHAL [2-4]. The spinel layer in the WL rim is present only on the hibonite and terminates abruptly at the contact with the coarse perovskite. This simple observation shows that the spinel layer is not a condensate in this case (otherwise spinel would have condensed on the perovskite as well). The spinel layer appears to have formed by gas-phase corrosion of the hibonite by Mg-rich vapors such that the spinel layer grew at the expense of the hibonite. We also found that the spinel layer has the same 16Orich composition as the hibonite. The spinel layer is polycrystalline and individual crystals do not show a crystallographic relationship with the hibonite. An Al-diopside layer overlies the spinel layer, and is present on both</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NIMPB.361...69R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NIMPB.361...69R"><span id="translatedtitle">Two years since SSAMS: Status of 14C AMS at <span class="hlt">CAIS</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ravi Prasad, G. V.; Cherkinsky, Alexander; Culp, Randy A.; Dvoracek, Doug K.</p> <p>2015-10-01</p> <p>The NEC 250 kV single stage AMS accelerator (SSAMS) was installed two years ago at the Center for Applied Isotope Studies (<span class="hlt">CAIS</span>), University of Georgia. The accelerator is primarily being used for radiocarbon measurements to test the authenticity of natural and bio-based samples while all other samples such as geological, atmospheric, marine and archaeological. are run on the 500 kV, NEC 1.5SDH-1 model tandem accelerator, which has been operating since 2001. The data obtained over a six months period for OXI, OXII, ANU sucrose and FIRI-D are discussed. The mean value of ANU sucrose observed to be slightly lower than the consensus value. The processed blanks on SSAMS produce lower apparent age compared to the tandem accelerator as expected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21731730','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21731730"><span id="translatedtitle">Qualitative real-time schlieren and shadowgraph <span class="hlt">imaging</span> of human exhaled airflows: an aid to <span class="hlt">aerosol</span> infection control.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tang, Julian W; Nicolle, Andre D G; Pantelic, Jovan; Jiang, Mingxiu; Sekhr, Chandra; Cheong, David K W; Tham, Kwok Wai</p> <p>2011-01-01</p> <p>Using a newly constructed airflow <span class="hlt">imaging</span> system, airflow patterns were visualized that were associated with common, everyday respiratory activities (e.g. breathing, talking, laughing, whistling). The effectiveness of various interventions (e.g. putting hands and tissues across the mouth and nose) to reduce the potential transmission of airborne infection, whilst coughing and sneezing, were also investigated. From the digital video footage recorded, it was seen that both coughing and sneezing are relatively poorly contained by commonly used configurations of single-handed shielding maneuvers. Only some but not all of the forward momentum of the cough and sneeze puffs are curtailed with various hand techniques, and the remaining momentum is disseminated in a large puff in the immediate vicinity of the cougher, which may still act as a nearby source of infection. The use of a tissue (in this case, 4-ply, opened and ready in the hand) proved to be surprisingly effective, though the effectiveness of this depends on the tissue remaining intact and not ripping apart. Interestingly, the use of a novel 'coughcatcher' device appears to be relatively effective in containing coughs and sneezes. One aspect that became evident during the experimental procedures was that the effectiveness of all of these barrier interventions is very much dependent on the speed with which the user can put them into position to cover the mouth and nose effectively.From these qualitative schlieren and shadowgraph <span class="hlt">imaging</span> experiments, it is clear that making some effort to contain one's cough or sneeze puffs is worthwhile. Obviously, there will be a large amount of variation between individuals in the exact hand or tissue (the most common methods) configuration used for this and other practical factors may hinder such maneuvers in daily life, for example, when carrying shopping bags or managing young children.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3120871','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3120871"><span id="translatedtitle">Qualitative Real-Time Schlieren and Shadowgraph <span class="hlt">Imaging</span> of Human Exhaled Airflows: An Aid to <span class="hlt">Aerosol</span> Infection Control</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tang, Julian W.; Nicolle, Andre D. G.; Pantelic, Jovan; Jiang, Mingxiu; Sekhr, Chandra; Cheong, David K. W.; Tham, Kwok Wai</p> <p>2011-01-01</p> <p>Using a newly constructed airflow <span class="hlt">imaging</span> system, airflow patterns were visualized that were associated with common, everyday respiratory activities (e.g. breathing, talking, laughing, whistling). The effectiveness of various interventions (e.g. putting hands and tissues across the mouth and nose) to reduce the potential transmission of airborne infection, whilst coughing and sneezing, were also investigated. From the digital video footage recorded, it was seen that both coughing and sneezing are relatively poorly contained by commonly used configurations of single-handed shielding maneuvers. Only some but not all of the forward momentum of the cough and sneeze puffs are curtailed with various hand techniques, and the remaining momentum is disseminated in a large puff in the immediate vicinity of the cougher, which may still act as a nearby source of infection. The use of a tissue (in this case, 4-ply, opened and ready in the hand) proved to be surprisingly effective, though the effectiveness of this depends on the tissue remaining intact and not ripping apart. Interestingly, the use of a novel ‘coughcatcher’ device appears to be relatively effective in containing coughs and sneezes. One aspect that became evident during the experimental procedures was that the effectiveness of all of these barrier interventions is very much dependent on the speed with which the user can put them into position to cover the mouth and nose effectively. From these qualitative schlieren and shadowgraph <span class="hlt">imaging</span> experiments, it is clear that making some effort to contain one's cough or sneeze puffs is worthwhile. Obviously, there will be a large amount of variation between individuals in the exact hand or tissue (the most common methods) configuration used for this and other practical factors may hinder such maneuvers in daily life, for example, when carrying shopping bags or managing young children. PMID:21731730</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120017003','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120017003"><span id="translatedtitle">Estimating Marine <span class="hlt">Aerosol</span> Particle Volume and Number from Maritime <span class="hlt">Aerosol</span> Network Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sayer, A. M.; Smirnov, A.; Hsu, N. C.; Munchak, L. A.; Holben, B. N.</p> <p>2012-01-01</p> <p>As well as spectral <span class="hlt">aerosol</span> optical depth (AOD), <span class="hlt">aerosol</span> composition and concentration (number, volume, or mass) are of interest for a variety of applications. However, remote sensing of these quantities is more difficult than for AOD, as it is more sensitive to assumptions relating to <span class="hlt">aerosol</span> composition. This study uses spectral AOD measured on Maritime <span class="hlt">Aerosol</span> Network (MAN) cruises, with the additional constraint of a microphysical model for unpolluted maritime <span class="hlt">aerosol</span> based on analysis of <span class="hlt">Aerosol</span> Robotic Network (AERONET) inversions, to estimate these quantities over open ocean. When the MAN data are subset to those likely to be comprised of maritime <span class="hlt">aerosol</span>, number and volume concentrations obtained are physically reasonable. Attempts to estimate surface concentration from columnar abundance, however, are shown to be limited by uncertainties in vertical distribution. Columnar AOD at 550 nm and <span class="hlt">aerosol</span> number for unpolluted maritime cases are also compared with Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) data, for both the present Collection 5.1 and forthcoming Collection 6. MODIS provides a best-fitting retrieval solution, as well as the average for several different solutions, with different <span class="hlt">aerosol</span> microphysical models. The average solution MODIS dataset agrees more closely with MAN than the best solution dataset. Terra tends to retrieve lower <span class="hlt">aerosol</span> number than MAN, and Aqua higher, linked with differences in the <span class="hlt">aerosol</span> models commonly chosen. Collection 6 AOD is likely to agree more closely with MAN over open ocean than Collection 5.1. In situations where spectral AOD is measured accurately, and <span class="hlt">aerosol</span> microphysical properties are reasonably well-constrained, estimates of <span class="hlt">aerosol</span> number and volume using MAN or similar data would provide for a greater variety of potential comparisons with <span class="hlt">aerosol</span> properties derived from satellite or chemistry transport model data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012E%26PSL.329...51S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012E%26PSL.329...51S"><span id="translatedtitle">Lithium isotope compositions of chondrules, <span class="hlt">CAI</span> and a dark inclusion from Allende and ordinary chondrites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seitz, Hans-Michael; Zipfel, Jutta; Brey, Gerhard P.; Ott, Ulrich</p> <p>2012-05-01</p> <p>Bulk carbonaceous and ordinary chondrites have distinct Li isotope compositions, indicating the existence of local reservoirs and distinct formation conditions in the early solar system. These differences may be also recorded in the components that compose chondrites. Here, Li concentrations and Li isotope compositions of 89 chondrules, 10 <span class="hlt">CAI</span> and 1 dark inclusion (DI) from the Allende (CV3) meteorite and from 5 ordinary chondrites of low petrologic types Semarkona, Bishunpur, Saratov, Bjurböle and Bremervörde are presented. In general, chondrules have highly variable Li isotope compositions, ranging from δ7Li of - 8.5 to + 10‰, whereby the mean isotope composition of chondrules separated from a single chondrite is slightly lighter than its bulk. Remarkable, however, are the differences in Li concentrations between bulk chondrite and chondrules. Of the entire set studied here, 98% of the chondrules have significantly lower Li abundances (in the range of 0.2 to 0.75 μg/g) than their hosts (typically around 1.5 μg/g). Our results indicate that Li elemental and isotopic fractionation has not occurred extensively during chondrule formation. Low, but highly variable Li abundances as well as the relatively large range in Li isotopes point to small-scale heterogeneities in the chondrule-forming reservoir. With respect to Li, such a non-chondritic reservoir is unique to all chondrules. The compositional differences in Li isotopes between bulk carbonaceous and ordinary chondrites (Seitz et al., 2007) are likely to be the result of mixing chondrules, <span class="hlt">CAI</span> and matrix in different proportions.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeCoA.102..261W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeCoA.102..261W"><span id="translatedtitle">Petrology, trace element abundances and oxygen isotopic compositions of a compound <span class="hlt">CAI</span>-chondrule object from Allende</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wakaki, S.; Itoh, S.; Tanaka, T.; Yurimoto, H.</p> <p>2013-02-01</p> <p>We report the petrology, trace element abundances and oxygen isotopic characteristics of a compound <span class="hlt">CAI</span>-chondrule object, WI-025, found in the Allende CV3 chondrite. The WI-025 is an irregularly shaped inclusion consisting of three texturally and chemically distinct portions: the interior portion, the igneous rim and the intermediate zone located between these two portions. The interior portion consists of anorthite, spinel, olivine and Al-bearing low-Ca pyroxene. The major element chemistry of the interior portion corresponds to that of Al-rich chondrules and is of intermediate character between fine-grained spinel-rich <span class="hlt">CAIs</span> and ferromagnesian chondrules. The interior portion has abundant 16O-rich spinel (Δ17O = -14.2 to -24.7) and displays a group II <span class="hlt">CAI</span>-like REE composition. These observations indicate that the interior portion contains a <span class="hlt">CAI</span> component formed by fractional condensation. The major and trace element chemistry of the interior portion indicate that the <span class="hlt">CAI</span> had subsequently assimilated chondrule materials through partial melting. The maximum heating temperature of the partial melting is estimated at approximately 1400 °C, similar to the maximum heating temperature of Type-B <span class="hlt">CAIs</span>. The oxygen isotopic compositions of the olivine and low-Ca pyroxene (Δ17O = -6.3) in the interior portion indicate that the partial melting and chondrule assimilation took place under a moderately 16O-poor nebular gas. The igneous rim is texturally and chemically similar to ferromagnesian chondrules and entirely surrounds the interior portion. The oxygen isotopic compositions of the olivine and low-Ca pyroxene in the igneous rim are indistinguishable from those of the interior olivine and Al-bearing low-Ca pyroxenes. These observations indicate that a chondrule material, which was melted in the same nebular gas as the interior portion, was accreted to the interior portion. The intermediate zone represents a reaction zone accompanying the igneous rim formation. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040004300','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040004300"><span id="translatedtitle"><span class="hlt">Aerosol</span> Models for the CALIPSO Lidar Inversion Algorithms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Omar, Ali H.; Winker, David M.; Won, Jae-Gwang</p> <p>2003-01-01</p> <p>We use measurements and models to develop <span class="hlt">aerosol</span> models for use in the inversion algorithms for the Cloud <span class="hlt">Aerosol</span> Lidar and <span class="hlt">Imager</span> Pathfinder Spaceborne Observations (CALIPSO). Radiance measurements and inversions of the <span class="hlt">AErosol</span> RObotic NETwork (AERONET1, 2) are used to group global atmospheric <span class="hlt">aerosols</span> using optical and microphysical parameters. This study uses more than 105 records of radiance measurements, <span class="hlt">aerosol</span> size distributions, and complex refractive indices to generate the optical properties of the <span class="hlt">aerosol</span> at more 200 sites worldwide. These properties together with the radiance measurements are then classified using classical clustering methods to group the sites according to the type of <span class="hlt">aerosol</span> with the greatest frequency of occurrence at each site. Six significant clusters are identified: desert dust, biomass burning, urban industrial pollution, rural background, marine, and dirty pollution. Three of these are used in the CALIPSO <span class="hlt">aerosol</span> models to characterize desert dust, biomass burning, and polluted continental <span class="hlt">aerosols</span>. The CALIPSO <span class="hlt">aerosol</span> model also uses the coarse mode of desert dust and the fine mode of biomass burning to build a polluted dust model. For marine <span class="hlt">aerosol</span>, the CALIPSO <span class="hlt">aerosol</span> model uses measurements from the SEAS experiment 3. In addition to categorizing the <span class="hlt">aerosol</span> types, the cluster analysis provides all the column optical and microphysical properties for each cluster.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeCoA.116...52R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeCoA.116...52R"><span id="translatedtitle">The texture of a fine-grained calcium-aluminium-rich inclusion (<span class="hlt">CAI</span>) in three dimensions and implications for early solar system condensation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Russell, Sara S.; Howard, Lauren</p> <p>2013-09-01</p> <p>A 16 mm fine-grained spinel-rich calcium-aluminium-rich inclusion (<span class="hlt">CAI</span>) from the Allende CV3 meteorite was analysed using nano-computed tomography and scanning electron microscopy on uncoated chips and a polished thin section. The <span class="hlt">CAI</span> is composed of spinel nodules surrounded by anorthite and Al-rich diopside rims. Minor secondary minerals including hedenbergite and nepheline are also present. The uncoated chips contain abundant wollastonite needles that are only rarely observed in the thin section. Nano-computed tomography shows that the structure of the <span class="hlt">CAI</span> is a branching interconnected network of nodules, most of which are attached to each other in three dimensions. However some nodules are unattached to the rest of the <span class="hlt">CAI</span>. The texture suggests that the <span class="hlt">CAI</span> formed by condensation from a gas, and condensation and aggregation of nodules occurred contemporaneously, implying a high density of newly-formed dust. One portion of the <span class="hlt">CAI</span> is compact and rich in melilite, with a composition and texture dissimilar to the bulk of the inclusion. We infer that this is a melilite-rich mantle of the same <span class="hlt">CAI</span> that has experienced melting on one side.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3335026','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3335026"><span id="translatedtitle">Airflow Dynamics of Coughing in Healthy Human Volunteers by Shadowgraph <span class="hlt">Imaging</span>: An Aid to <span class="hlt">Aerosol</span> Infection Control</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tang, Julian W.; Nicolle, Andre; Pantelic, Jovan; Koh, Gerald C.; Wang, Liang De; Amin, Muhammad; Klettner, Christian A.; Cheong, David K. W.; Sekhar, Chandra; Tham, Kwok Wai</p> <p>2012-01-01</p> <p>Cough airflow dynamics have been previously studied using a variety of experimental methods. In this study, real-time, non-invasive shadowgraph <span class="hlt">imaging</span> was applied to obtain additional analyses of cough airflows produced by healthy volunteers. Twenty healthy volunteers (10 women, mean age 32.2±12.9 years; 10 men, mean age 25.3±2.5 years) were asked to cough freely, then into their sleeves (as per current US CDC recommendations) in this study to analyze cough airflow dynamics. For the 10 females (cases 1–10), their maximum detectable cough propagation distances ranged from 0.16–0.55 m, with maximum derived velocities of 2.2–5.0 m/s, and their maximum detectable 2-D projected areas ranged from 0.010–0.11 m2, with maximum derived expansion rates of 0.15–0.55 m2/s. For the 10 males (cases 11–20), their maximum detectable cough propagation distances ranged from 0.31–0.64 m, with maximum derived velocities of 3.2–14 m/s, and their maximum detectable 2-D projected areas ranged from 0.04–0.14 m2, with maximum derived expansion rates of 0.25–1.4 m2/s. These peak velocities were measured when the visibility of the exhaled airflows was optimal and compare favorably with those reported previously using other methods, and may be seen as a validation of these previous approaches in a more natural setting. However, the propagation distances can only represent a lower limit due to the inability of the shadowgraph method to visualize these cough airflows once their temperature cools to that of the ambient air, which is an important limitation of this methodology. The qualitative high-speed video footage of these volunteers coughing into their sleeves demonstrates that although this method rarely completely blocks the cough airflow, it decelerates, splits and redirects the airflow, eventually reducing its propagation. The effectiveness of this intervention depends on optimum positioning of the arm over the nose and mouth during coughing, though unsightly stains</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015M%26PS...50.1512I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015M%26PS...50.1512I"><span id="translatedtitle">A compound Ca-, Al-rich inclusion from CV3 chondrite Northwest Africa 3118: Implications for understanding processes during <span class="hlt">CAI</span> formation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ivanova, Marina A.; Lorenz, Cyril A.; Krot, Alexander N.; MacPherson, Glenn J.</p> <p>2015-09-01</p> <p>A calcium-aluminum-rich inclusion 3N from the Northwest Africa (NWA) 3118 CV3 carbonaceous chondrite is a unique cm-sized compound object, primarily a forsterite-bearing type B (FoB) <span class="hlt">CAI</span>, that encloses at least 26 smaller <span class="hlt">CAIs</span> of different types, including compact type A (CTA), B, C, and an ultra-refractory inclusion. Relative to typical type A and B <span class="hlt">CAIs</span> found elsewhere, the bulk compositions of the types A and B <span class="hlt">CAIs</span> within 3N more closely match the bulk compositions predicted by equilibrium condensation of a gas of solar composition. Being trapped within the FoB melt may have protected them from melt evaporation that affected most "stand-alone" <span class="hlt">CAIs</span>. 3N originated either as an aggregate of many smaller (mostly types A, B, C) <span class="hlt">CAIs</span> plus accreted Fo-bearing material (like an amoeboid olivine aggregate) which experienced partial melting of the whole, or else as a FoB melt droplet that collided with and trapped many smaller solid <span class="hlt">CAIs</span>. In the former case, 3N recorded the earliest accretion of pebble-sized bodies known. In the latter case, the presence of a large number of individual refractory inclusions within 3N suggests a very high local density of refractory solids in the immediate region of the host <span class="hlt">CAI</span> during the brief time while it was melted. Collisions would have occurred on time scales of hours at most, assuming a melt solidification interval for the host <span class="hlt">CAI</span> of 300-400 °C (maximum) and a cooling rate of ~10 °C/h.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011689','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011689"><span id="translatedtitle">Global Atmospheric <span class="hlt">Aerosol</span> Modeling</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hendricks, Johannes; Aquila, Valentina; Righi, Mattia</p> <p>2012-01-01</p> <p>Global <span class="hlt">aerosol</span> models are used to study the distribution and properties of atmospheric <span class="hlt">aerosol</span> particles as well as their effects on clouds, atmospheric chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global atmospheric <span class="hlt">aerosol</span> modeling and shows some examples from a global <span class="hlt">aerosol</span> simulation. Particular emphasis is placed on the simulation of <span class="hlt">aerosol</span> particles and their effects within global climate models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20160009531&hterms=satellite&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsatellite','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20160009531&hterms=satellite&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsatellite"><span id="translatedtitle">New Satellite Project <span class="hlt">Aerosol</span>-UA: Remote Sensing of <span class="hlt">Aerosols</span> in the Terrestrial Atmosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Milinevsky, G.; Yatskiv, Ya.; Degtyaryov, O.; Syniavskyi, I.; Mishchenko, Michael I.; Rosenbush, V.; Ivanov, Yu.; Makarov, A.; Bovchaliuk, A.; Danylevsky, V.; Sosonkin, M.; Moskalov, S.; Bovchaliuk, V; Lukenyuk, A.; Shymkiv, A.</p> <p>2016-01-01</p> <p>We discuss the development of the Ukrainian space project <span class="hlt">Aerosol</span>-UA which has the following three main objectives: (1) to monitor the spatial distribution of key characteristics of terrestrial tropospheric and stratospheric <span class="hlt">aerosols</span>; (2) to provide a comprehensive observational database enabling accurate quantitative estimates of the <span class="hlt">aerosol</span> contribution to the energy budget of the climate system; and (3) quantify the contribution of anthropogenic <span class="hlt">aerosols</span> to climate and ecological processes. The remote sensing concept of the project is based on precise orbital measurements of the intensity and polarization of sunlight scattered by the atmosphere and the surface with a scanning polarimeter accompanied by a wide-angle multispectral <span class="hlt">imager</span>-polarimeter. Preparations have already been made for the development of the instrument suite for the <span class="hlt">Aerosol</span>-UA project, in particular, of the multi-channel scanning polarimeter (ScanPol) designed for remote sensing studies of the global distribution of <span class="hlt">aerosol</span> and cloud properties (such as particle size, morphology, and composition) in the terrestrial atmosphere by polarimetric and spectrophotometric measurements of the scattered sunlight in a wide range of wavelengths and viewing directions from which a scene location is observed. ScanPol is accompanied by multispectral wide-angle <span class="hlt">imager</span>-polarimeter (MSIP) that serves to collect information on cloud conditions and Earths surface <span class="hlt">image</span>. Various components of the polarimeter ScanPol have been prototyped, including the opto-mechanical and electronic assemblies and the scanning mirror controller. Preliminary synthetic data simulations for the retrieval of <span class="hlt">aerosol</span> parameters over land surfaces have been performed using the Generalized Retrieval of <span class="hlt">Aerosol</span> and Surface Properties (GRASP) algorithm. Methods for the validation of satellite data using ground-based observations of <span class="hlt">aerosol</span> properties are also discussed. We assume that designing, building, and launching into orbit a multi</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AcAau.123..292M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AcAau.123..292M"><span id="translatedtitle">New satellite project <span class="hlt">Aerosol</span>-UA: Remote sensing of <span class="hlt">aerosols</span> in the terrestrial atmosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Milinevsky, G.; Yatskiv, Ya.; Degtyaryov, O.; Syniavskyi, I.; Mishchenko, M.; Rosenbush, V.; Ivanov, Yu.; Makarov, A.; Bovchaliuk, A.; Danylevsky, V.; Sosonkin, M.; Moskalov, S.; Bovchaliuk, V.; Lukenyuk, A.; Shymkiv, A.; Udodov, E.</p> <p>2016-06-01</p> <p>We discuss the development of the Ukrainian space project <span class="hlt">Aerosol</span>-UA which has the following three main objectives: (1) to monitor the spatial distribution of key characteristics of terrestrial tropospheric and stratospheric <span class="hlt">aerosols</span>; (2) to provide a comprehensive observational database enabling accurate quantitative estimates of the <span class="hlt">aerosol</span> contribution to the energy budget of the climate system; and (3) quantify the contribution of anthropogenic <span class="hlt">aerosols</span> to climate and ecological processes. The remote sensing concept of the project is based on precise orbital measurements of the intensity and polarization of sunlight scattered by the atmosphere and the surface with a scanning polarimeter accompanied by a wide-angle multispectral <span class="hlt">imager</span>-polarimeter. Preparations have already been made for the development of the instrument suite for the <span class="hlt">Aerosol</span>-UA project, in particular, of the multi-channel scanning polarimeter (ScanPol) designed for remote sensing studies of the global distribution of <span class="hlt">aerosol</span> and cloud properties (such as particle size, morphology, and composition) in the terrestrial atmosphere by polarimetric and spectrophotometric measurements of the scattered sunlight in a wide range of wavelengths and viewing directions from which a scene location is observed. ScanPol is accompanied by multispectral wide-angle <span class="hlt">imager</span>-polarimeter (MSIP) that serves to collect information on cloud conditions and Earth's surface <span class="hlt">image</span>. Various components of the polarimeter ScanPol have been prototyped, including the opto-mechanical and electronic assemblies and the scanning mirror controller. Preliminary synthetic data simulations for the retrieval of <span class="hlt">aerosol</span> parameters over land surfaces have been performed using the Generalized Retrieval of <span class="hlt">Aerosol</span> and Surface Properties (GRASP) algorithm. Methods for the validation of satellite data using ground-based observations of <span class="hlt">aerosol</span> properties are also discussed. We assume that designing, building, and launching into orbit a multi</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=163264&keyword=Aeronautics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=68470442&CFTOKEN=42252773','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=163264&keyword=Aeronautics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=68470442&CFTOKEN=42252773"><span id="translatedtitle">A COMPARISON OF CMAQ-BASED <span class="hlt">AEROSOL</span> PROPERTIES WITH IMPROVE, MODIS, AND AERONET DATA</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>We compare select <span class="hlt">aerosol</span> Properties derived from the Community Multiscale Air Quality (CMAQ) model-simulated <span class="hlt">aerosol</span> mass concentrations with routine data from the National Aeronautics and Space Administration (NASA) satellite-borne Moderate Resolution <span class="hlt">Imaging</span> Spectro-radiometer...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100027520','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100027520"><span id="translatedtitle"><span class="hlt">Aerosol</span> gels</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sorensen, Christopher M. (Inventor); Chakrabarti, Amitabha (Inventor); Dhaubhadel, Rajan (Inventor); Gerving, Corey (Inventor)</p> <p>2010-01-01</p> <p>An improved process for the production of ultralow density, high specific surface area gel products is provided which comprises providing, in an enclosed chamber, a mixture made up of small particles of material suspended in gas; the particles are then caused to aggregate in the chamber to form ramified fractal aggregate gels. The particles should have a radius (a) of up to about 50 nm and the <span class="hlt">aerosol</span> should have a volume fraction (f.sub.v) of at least 10.sup.-4. In preferred practice, the mixture is created by a spark-induced explosion of a precursor material (e.g., a hydrocarbon) and oxygen within the chamber. New compositions of matter are disclosed having densities below 3.0 mg/cc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20919396','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20919396"><span id="translatedtitle">An experimental study of the combustion characteristics in SCCI and <span class="hlt">CAI</span> based on direct-injection gasoline engine</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lee, C.H.; Lee, K.H.</p> <p>2007-08-15</p> <p>Emissions remain a critical issue affecting engine design and operation, while energy conservation is becoming increasingly important. One approach to favorably address these issues is to achieve homogeneous charge combustion and stratified charge combustion at lower peak temperatures with a variable compression ratio, a variable intake temperature and a trapped rate of the EGR using NVO (negative valve overlap). This experiment was attempted to investigate the origins of these lower temperature auto-ignition phenomena with SCCI and <span class="hlt">CAI</span> using gasoline fuel. In case of SCCI, the combustion and emission characteristics of gasoline-fueled stratified-charge compression ignition (SCCI) engine according to intake temperature and compression ratio was examined. We investigated the effects of air-fuel ratio, residual EGR rate and injection timing on the <span class="hlt">CAI</span> combustion area. In addition, the effect of injection timing on combustion factors such as the start of combustion, its duration and its heat release rate was also investigated. (author)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009GeCoA..73.5100P&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009GeCoA..73.5100P&link_type=ABSTRACT"><span id="translatedtitle">Petrologic study of SJ101, a new forsterite-bearing <span class="hlt">CAI</span> from the Allende CV3 chondrite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petaev, Michail I.; Jacobsen, Stein B.</p> <p>2009-09-01</p> <p>The forsterite-bearing Type B (FoB) <span class="hlt">CAI</span> SJ101 consists of three major structural units: (1) light patches of sector-zoned, poikilitic Al-rich clinopyroxene (Cpx) with numerous inclusions of small spinel grains and aggregates and subordinate amounts of Mg-rich melilite (Mel) and anorthite (An) (Sp-Cpx lithology), (2) dark sinuous bands of Al-rich clinopyroxene with large (up to ˜300 × 60 μm) poikilitically enclosed euhedral forsterite (Fo) crystals (Fo-Cpx lithology), and (3) the external Cpx-Sp-An rim overlying the entire inclusion. The two major lithologies are always separated by a transition zone of clinopyroxene poikilitically enclosing both forsterite and spinel. The patches of the Sp-Cpx lithology exhibit significant textural and mineralogical variability that is size-dependent. Small patches typically consist of Cpx and spinel with minor remnants of melilite and/or its alteration products. Large patches contain Mel-An-rich cores with either equigranular-ophitic-subophitic or 'lacy' textures reminiscent of those in Types B or C <span class="hlt">CAIs</span>, respectively. All silicates poikilitically enclose numerous spinel grains of identical habit. Both melilite and anorthite gradually disappear toward the boundary with the Fo-Cpx lithology. Neither the evaporation mantle of Al-rich melilite typical of other FoBs nor the Wark-Lovering rim is present. Secondary minerals include grossular, monticellite, magnetite, and a few grains of wollastonite, andradite, and nepheline. Being a rather typical FoB mineralogically and chemically, texturally SJ101 differs from other FoBs in displaying the nearly complete segregation of forsterite from spinel which occur only in the Fo-Cpx and Sp-Cpx lithologies, respectively. The complex, convoluted internal structure of SJ101 suggests that the coarse-grained Sp-An-Mel-Cpx cores and Fo-Cpx lithology represent the precursor materials of FoBs, proto-<span class="hlt">CAIs</span> and Fo-rich accretionary rims. While the inferred chemistry and mineralogy of the Fo-rich rims</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AtmEn.123..392T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AtmEn.123..392T"><span id="translatedtitle">Climatic analysis of satellite <span class="hlt">aerosol</span> data on variations of submicron <span class="hlt">aerosols</span> over East China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tan, Chenghao; Zhao, Tianliang; Xu, Xiaofeng; Liu, Jane; Zhang, Lei; Tang, Lili</p> <p>2015-12-01</p> <p>Recently, haze events frequently occurred in East China. To assess the impacts of <span class="hlt">aerosols</span> on air quality over the region, we investigate the interannual variations of the total <span class="hlt">aerosols</span> and the submicron <span class="hlt">aerosols</span>, in terms of the <span class="hlt">aerosol</span> mass concentration (AMC) and Fine Mode Fraction (FMF), respectively, using the Moderate Resolution <span class="hlt">Imaging</span> Spectrometer (MODIS) <span class="hlt">aerosol</span> products, which can be used for regional air quality assessment, from 2003 to 2013. On average, the AMC distributes as "northern high and southern low", whereas the FMF shows a "northern low and southern high" pattern. High FMF occurs in the warm seasons, but low FMF appears in the cool seasons. During the 10 years, the AMC shows increasing trend in northern and decreasing trend in southeastern parts of the region, whereas an increasing trend in the FMF is observed over the entire East China, likely related to elevated submicron <span class="hlt">aerosols</span> from anthropogenic sources. The East Asian summer monsoon impacts the submicron <span class="hlt">aerosols</span> more than the total <span class="hlt">aerosols</span>. The enhanced submicron <span class="hlt">aerosols</span> are responsible for rapid deterioration of air quality in East China in recent years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815332M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815332M"><span id="translatedtitle"><span class="hlt">Aerosol</span> typing - key information from <span class="hlt">aerosol</span> studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mona, Lucia; Kahn, Ralph; Papagiannopoulos, Nikolaos; Holzer-Popp, Thomas; Pappalardo, Gelsomina</p> <p>2016-04-01</p> <p><span class="hlt">Aerosol</span> typing is a key source of <span class="hlt">aerosol</span> information from ground-based and satellite-borne instruments. Depending on the specific measurement technique, <span class="hlt">aerosol</span> typing can be used as input for retrievals or represents an output for other applications. Typically <span class="hlt">aerosol</span> retrievals require some a priori or external <span class="hlt">aerosol</span> type information. The accuracy of the derived <span class="hlt">aerosol</span> products strongly depends on the reliability of these assumptions. Different sensors can make use of different <span class="hlt">aerosol</span> type inputs. A critical review and harmonization of these procedures could significantly reduce related uncertainties. On the other hand, satellite measurements in recent years are providing valuable information about the global distribution of <span class="hlt">aerosol</span> types, showing for example the main source regions and typical transport paths. Climatological studies of <span class="hlt">aerosol</span> load at global and regional scales often rely on inferred <span class="hlt">aerosol</span> type. There is still a high degree of inhomogeneity among satellite <span class="hlt">aerosol</span> typing schemes, which makes the use different sensor datasets in a consistent way difficult. Knowledge of the 4d <span class="hlt">aerosol</span> type distribution at these scales is essential for understanding the impact of different <span class="hlt">aerosol</span> sources on climate, precipitation and air quality. All this information is needed for planning upcoming <span class="hlt">aerosol</span> emissions policies. The exchange of expertise and the communication among satellite and ground-based measurement communities is fundamental for improving long-term dataset consistency, and for reducing <span class="hlt">aerosol</span> type distribution uncertainties. <span class="hlt">Aerosol</span> typing has been recognized as one of its high-priority activities of the AEROSAT (International Satellite <span class="hlt">Aerosol</span> Science Network, http://aero-sat.org/) initiative. In the AEROSAT framework, a first critical review of <span class="hlt">aerosol</span> typing procedures has been carried out. The review underlines the high heterogeneity in many aspects: approach, nomenclature, assumed number of components and parameters used for the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994Metic..29..461E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994Metic..29..461E"><span id="translatedtitle">Efremovka E49: A compact type-A <span class="hlt">CAI</span> containing a partially molten spinel-melilite-diopside xenolith</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>El Goresy, A.; Zinner, E. K.</p> <p>1994-07-01</p> <p>Eframovka E49 is a triangular 2-mm segment from a Compact Type A (CTA) inclusion with large portions of intact core and rim sequence. It is probably a fragment from an originally round approximately equal to 4-mm Ca-Al rich Inclusion (<span class="hlt">CAI</span>). The core consists of two lithologically different assemblages: (1) The major portion of the <span class="hlt">CAI</span> contains melilite sprinkled with rare spinel, perovskite, and the new Ca-Ti silicate. It is covered by a six-layer rim consisting of (from the interior outward): two layers of Zr- and Y-rich perovskite, spinel, Al-diopside, diopside, and forsteritic olivine. (2) A 650-micron wide complex xenolith contains coarse spinel, melilite, perovskite, and metal in its interior, surrounded by a broad shell of Al-diopside, diopside, and minor fassaite and anorthite, and in the rim fassaite yields Al-diopside yields diopside. Coarse spinels abundantly display resorbtion outlines and some of the grains have been broken down to several amoeboid fragments floating in the eutectic assemblage. All these textures are evidence of local melting of the xenolith followed by fast cooling. No such features are observed in the host <span class="hlt">CAI</span>. Since melting is confined to the xenolith, the melt event must have predated its capture into the core of E49. Ion microprobe trace-element studies reveal distinct differences between Rare Earth Element (REE) abundances in perovskites in the xenolith and the host <span class="hlt">CAI</span>. Perovskites in the xenolith display REE patterns with prominent Yb and small Ce excesses and large Eu depletions. Perovskites in the xenolith show higher abundances of Nb, Zr, and V. Magnesium in xenolith and the host is almost unfractionated. Excesses of Mg-26 are found both in the xenolith and the host with data points plotting along a line with a slope of 4 x 105. This is in accord with the petrographic interpretation and indicates that the melting of the xenolith and its capture in E49 took place early.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19950012911&hterms=Fractionation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DFractionation','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19950012911&hterms=Fractionation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DFractionation"><span id="translatedtitle">Heating during solar nebula formation and Mg isotopic fractionation in precursor grains of <span class="hlt">CAIs</span> and chondrules</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sasaki, S.; Nagahara, H.; Kitagami, K.; Nakagawa, Y.</p> <p>1994-01-01</p> <p>In some Ca-Al-rich inclusion (<span class="hlt">CAI</span>) grains, mass-dependent isotopic fractionations of Mg, Si, and O are observed and large Mg isotopic fractionation is interpreted to have been produced by cosmochemical processes such as evaporation and condensation. Mass-dependent Mg isotopic fractionation was found in olivine chondrules of Allende meteorites. Presented is an approximate formula for the temperature of the solar nebula that depends on heliocentric distance and the initial gas distribution. Shock heating during solar nebula formation can cause evaporative fractionation within interstellar grains involved in a gas at the inner zone (a less than 3 AU) of the disk. Alternatively collision of late-accreting gas blobs might cause similar heating if Sigma(sub s) and Sigma are large enough. Since the grain size is small, the solid/gas mass ratio is low and solar (low P(sub O2)), and the ambient gas pressure is low, this heating event could not produce chondrules themselves. Chondrule formation should proceed around the disk midplane after dust grains would grow and sediment to increase the solid/gas ratio there. The heating source there is uncertain, but transient rapid accretion through the disk could release a large amount of heat, which would be observed as FU Orionis events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A23B3218B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A23B3218B"><span id="translatedtitle"><span class="hlt">Aerosol</span>/Radiation, VNIR/NIR/TIR <span class="hlt">Imaging</span>, Net Solar and Longwave Radiation, Meteorological Fluxes, Atmospheric Dropsonde, and Ocean Temperature/Salinity Microbuoy Payloads for Earth Observations Using a Manta Unmanned Aerial System (UAS)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bates, T. S.; Gao, R. S.; Murphy, D. M.; Telg, H.; Brown, S.; Dhakai, T.; Zappa, C. J.; Stalin, S.</p> <p>2014-12-01</p> <p>Several new payloads have been developed for use in the Manta UAS. The NOAA/PMEL <span class="hlt">aerosol</span> payload (Atmos. Meas. Tech., 6, 2115-2120, 2013) has been expanded to include a printed optical particle spectrometer to obtain <span class="hlt">aerosol</span> size distributions and an upward looking radiometer to measure radiant flux densities through <span class="hlt">aerosol</span> layers. Lamont-Doherty Earth Observatory (LDEO) has improved its visible and infrared <span class="hlt">imaging</span> payload to provide precise measurements of ice/snow/ocean surface temperatures accurate to 0.1°C. LDEO has also developed a number of new payloads that include: i) hyperspectral aberration-corrected <span class="hlt">imaging</span> spectrometers to measure VNIR (400-1000 nm) and NIR (900-1700 nm) spectral radiance of the upper-ocean and sea ice to determine ocean color, ice-age distributions and ice-surface type; ii) up- and downward-looking hemispheric pyrgeometers and pyranometers to measure the net longwave and net shortwave radiation for ice-ocean albedo studies with an onboard visible camera to determine the sea ice fraction and whitecapping; iii) meteorological measurements of turbulent momentum, sensible, and latent fluxes as well as wave height, ice freeboard, and surface roughness with a LIDAR; iv) four dropsonde-microbuoys (DMB) that can be deployed from the Manta. The four DMB measure temperature, pressure, and relative humidity as they descend through the atmosphere. Once they land on the ocean's surface, they deploy a string of sensors that measures temperature and salinity of the upper three meters of the ocean. The ocean sensors telemeter data back to the UAS on subsequent flights. The DMB can also be dropped on an ice flow to measure the rate of the ice movement. Details of these payloads and example data will be reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19850054072&hterms=Prizes&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D10%26Ntt%3DPrizes','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19850054072&hterms=Prizes&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D10%26Ntt%3DPrizes"><span id="translatedtitle">Willy: A prize noble Ur-Fremdling - Its history and implications for the formation of Fremdlinge and <span class="hlt">CAI</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Armstrong, J. T.; El Goresy, A.; Wasserburg, G. J.</p> <p>1985-01-01</p> <p>The structure and composition of Willy, a 150-micron-diameter Fremdling in <span class="hlt">CAI</span> 5241 from the Allende meteorite, are investigated using optical, secondary-electron, and electron-backscatter microscopy and electron-microprobe analysis. The results are presented in diagrams, maps, tables, graphs, and micrographs and compared with those for other Allende Fremdlinge. Willy is found to have a concentric-zone structure comprising a complex porous core of magnetite, metal, sulfide, scheelite, and other minor phases; a compact magnetite-apatite mantle; a thin (20 microns or less) reaction-assemblage zone; and a dense outer rim of fassaite with minor spinel. A multistage formation sequence involving changes in T and fO2 and preceding the introduction of Willy into the <span class="hlt">CAI</span> (which itself preceded <span class="hlt">CAI</span> spinel and silicate formation) is postulated, and it is inferred from the apparent lack of post-capture recrystallization that Willy has not been subjected to temperatures in excess of 600 C and may represent the precursor material for many other Fremdlinge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..DFDG16007M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..DFDG16007M"><span id="translatedtitle">An <span class="hlt">image</span>-based automatic mesh generation and numerical simulation for a population-based analysis of <span class="hlt">aerosol</span> delivery in the human lungs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miyawaki, Shinjiro; Tawhai, Merryn H.; Hoffman, Eric A.; Lin, Ching-Long</p> <p>2013-11-01</p> <p>The authors propose a method to automatically generate three-dimensional subject-specific airway geometries and meshes for computational fluid dynamics (CFD) studies of <span class="hlt">aerosol</span> delivery in the human lungs. The proposed method automatically expands computed tomography (CT)-based airway skeleton to generate the centerline (CL)-based model, and then fits it to the CT-segmented geometry to generate the hybrid CL-CT-based model. To produce a turbulent laryngeal jet known to affect <span class="hlt">aerosol</span> transport, we developed a physiologically-consistent laryngeal model that can be attached to the trachea of the above models. We used Gmsh to automatically generate the mesh for the above models. To assess the quality of the models, we compared the regional <span class="hlt">aerosol</span> distributions in a human lung predicted by the hybrid model and the manually generated CT-based model. The <span class="hlt">aerosol</span> distribution predicted by the hybrid model was consistent with the prediction by the CT-based model. We applied the hybrid model to 8 healthy and 16 severe asthmatic subjects, and average geometric error was 3.8% of the branch radius. The proposed method can be potentially applied to the branch-by-branch analyses of a large population of healthy and diseased lungs. NIH Grants R01-HL-094315 and S10-RR-022421, CT data provided by SARP, and computer time provided by XSEDE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9840748','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9840748"><span id="translatedtitle">Evaluation of neutralized chemical agent identification sets (<span class="hlt">CAIS</span>) for skin injury with an overview of the vesicant potential of agent degradation products.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Olajos, E J; Olson, C T; Salem, H; Singer, A W; Hayes, T L; Menton, R G; Miller, T L; Rosso, T; MacIver, B</p> <p>1998-01-01</p> <p>Vesication and skin irritation studies were conducted in hairless guinea-pigs to determine the vesicant and skin irritation potential of chemically-neutralized Chemical Agent Identification Sets (<span class="hlt">CAIS</span>). The <span class="hlt">CAIS</span> are training items that contain chemical warfare-related material--sulfur mustard (HD), nitrogen mustard (HN) or lewisite (L)--and were declared obsolete in 1971. Animals were dosed topically with 'test article'--neat HD, 10% agent/chloroform solutions or product solutions (waste-streams) from neutralized <span class="hlt">CAIS</span>--and evaluated for skin-damaging effects (gross and microscopic). Product solutions from the chemical neutralization of neat sulfur mustard resulted in microvesicle formation. All agent-dosed (HD or agent/chloroform solutions) sites manifested microblisters as well as other histopathological lesions of the skin. Waste-streams from the neutralization of agent (agent/chloroform or agent/charcoal) were devoid of vesicant activity. Cutaneous effects (erythema and edema) were consistent with the skin-injurious activity associated with the neutralizing reagent 1,3-dichloro-5,5-dimethylhydantoin (DCDMH). Chemical neutralization of <span class="hlt">CAIS</span> was effective in eliminating/reducing the vesicant property of <span class="hlt">CAIS</span> containing agent in chloroform or agent on charcoal but was inefficient in reducing the vesicant potential of <span class="hlt">CAIS</span> containing neat sulfur mustard.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/919902','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/919902"><span id="translatedtitle"><span class="hlt">Aerosol</span> mobility size spectrometer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Wang, Jian; Kulkarni, Pramod</p> <p>2007-11-20</p> <p>A device for measuring <span class="hlt">aerosol</span> size distribution within a sample containing <span class="hlt">aerosol</span> particles. The device generally includes a spectrometer housing defining an interior chamber and a camera for recording <span class="hlt">aerosol</span> size streams exiting the chamber. The housing includes an inlet for introducing a flow medium into the chamber in a flow direction, an <span class="hlt">aerosol</span> injection port adjacent the inlet for introducing a charged <span class="hlt">aerosol</span> sample into the chamber, a separation section for applying an electric field to the <span class="hlt">aerosol</span> sample across the flow direction and an outlet opposite the inlet. In the separation section, the <span class="hlt">aerosol</span> sample becomes entrained in the flow medium and the <span class="hlt">aerosol</span> particles within the <span class="hlt">aerosol</span> sample are separated by size into a plurality of <span class="hlt">aerosol</span> flow streams under the influence of the electric field. The camera is disposed adjacent the housing outlet for optically detecting a relative position of at least one <span class="hlt">aerosol</span> flow stream exiting the outlet and for optically detecting the number of <span class="hlt">aerosol</span> particles within the at least one <span class="hlt">aerosol</span> flow stream.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008E%26PSL.272..353J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008E%26PSL.272..353J"><span id="translatedtitle">26Al- 26Mg and 207Pb- 206Pb systematics of Allende <span class="hlt">CAIs</span>: Canonical solar initial 26Al/ 27Al ratio reinstated</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jacobsen, Benjamin; Yin, Qing-zhu; Moynier, Frederic; Amelin, Yuri; Krot, Alexander N.; Nagashima, Kazuhide; Hutcheon, Ian D.; Palme, Herbert</p> <p>2008-07-01</p> <p>The precise knowledge of the initial 26Al/ 27Al ratio [( 26Al/ 27Al) 0] is crucial if we are to use the very first solid objects formed in our Solar System, calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>) as the "time zero" age-anchor and guide future work with other short-lived radio-chronometers in the early Solar System, as well as determining the inventory of heat budgets from radioactivities for early planetary differentiation. New high-precision multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) measurements of 27Al/ 24Mg ratios and Mg-isotopic compositions of nine whole-rock <span class="hlt">CAIs</span> (six mineralogically characterized fragments and three micro-drilled inclusions) from the CV carbonaceous chondrite, Allende yield a well-defined 26Al- 26Mg fossil isochron with an ( 26Al/ 27Al) 0 of (5.23 ± 0.13) × 10 - 5 . Internal mineral isochrons obtained for three of these <span class="hlt">CAIs</span> ( A44A, AJEF, and A43) are consistent with the whole-rock <span class="hlt">CAI</span> isochron. The mineral isochron of AJEF with ( 26Al/ 27Al) 0 = (4.96 ± 0.25) × 10 - 5 , anchored to our precisely determined absolute 207Pb- 206Pb age of 4567.60 ± 0.36 Ma for the same mineral separates, reinstate the "canonical" ( 26Al/ 27Al) 0 of 5 × 10 - 5 for the early Solar System. The uncertainty in ( 26Al/ 27Al) 0 corresponds to a maximum time span of ± 20 Ka (thousand years), suggesting that the Allende <span class="hlt">CAI</span> formation events were culminated within this time span. Although all Allende <span class="hlt">CAIs</span> studied experienced multistage formation history, including melting and evaporation in the solar nebula and post-crystallization alteration likely on the asteroidal parent body, the 26Al- 26Mg and U-Pb-isotopic systematics of the mineral separates and bulk <span class="hlt">CAIs</span> behaved largely as closed-system since their formation. Our data do not support the "supra-canonical" 26Al/ 27Al ratio of individual minerals or their mixtures in CV <span class="hlt">CAIs</span>, suggesting that the supra-canonical 26Al/ 27Al ratio in the CV <span class="hlt">CAIs</span> may have resulted from post</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=62967&keyword=clouds&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=79252324&CFTOKEN=31881809','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=62967&keyword=clouds&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=79252324&CFTOKEN=31881809"><span id="translatedtitle"><span class="hlt">AEROSOL</span> AND GAS MEASUREMENT</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Measurements provide fundamental information for evaluating and managing the impact of <span class="hlt">aerosols</span> on air quality. Specific measurements of <span class="hlt">aerosol</span> concentration and their physical and chemical properties are required by different users to meet different user-community needs. Befo...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010NW.....97..117C&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010NW.....97..117C&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Aerosols</span> and environmental pollution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Colbeck, Ian; Lazaridis, Mihalis</p> <p>2010-02-01</p> <p>The number of publications on atmospheric <span class="hlt">aerosols</span> has dramatically increased in recent years. This review, predominantly from a European perspective, summarizes the current state of knowledge of the role played by <span class="hlt">aerosols</span> in environmental pollution and, in addition, highlights gaps in our current knowledge. <span class="hlt">Aerosol</span> particles are ubiquitous in the Earth’s atmosphere and are central to many environmental issues; ranging from the Earth’s radiative budget to human health. <span class="hlt">Aerosol</span> size distribution and chemical composition are crucial parameters that determine their dynamics in the atmosphere. Sources of <span class="hlt">aerosols</span> are both anthropogenic and natural ranging from vehicular emissions to dust resuspension. Ambient concentrations of <span class="hlt">aerosols</span> are elevated in urban areas with lower values at rural sites. A comprehensive understanding of <span class="hlt">aerosol</span> ambient characteristics requires a combination of measurements and modeling tools. Legislation for ambient <span class="hlt">aerosols</span> has been introduced at national and international levels aiming to protect human health and the environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19727639','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19727639"><span id="translatedtitle"><span class="hlt">Aerosols</span> and environmental pollution.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Colbeck, Ian; Lazaridis, Mihalis</p> <p>2010-02-01</p> <p>The number of publications on atmospheric <span class="hlt">aerosols</span> has dramatically increased in recent years. This review, predominantly from a European perspective, summarizes the current state of knowledge of the role played by <span class="hlt">aerosols</span> in environmental pollution and, in addition, highlights gaps in our current knowledge. <span class="hlt">Aerosol</span> particles are ubiquitous in the Earth's atmosphere and are central to many environmental issues; ranging from the Earth's radiative budget to human health. <span class="hlt">Aerosol</span> size distribution and chemical composition are crucial parameters that determine their dynamics in the atmosphere. Sources of <span class="hlt">aerosols</span> are both anthropogenic and natural ranging from vehicular emissions to dust resuspension. Ambient concentrations of <span class="hlt">aerosols</span> are elevated in urban areas with lower values at rural sites. A comprehensive understanding of <span class="hlt">aerosol</span> ambient characteristics requires a combination of measurements and modeling tools. Legislation for ambient <span class="hlt">aerosols</span> has been introduced at national and international levels aiming to protect human health and the environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A33C0178Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A33C0178Y"><span id="translatedtitle"><span class="hlt">Aerosol</span> direct radiative effect over China estimated with visibility measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ye, K.; Lin, J.</p> <p>2012-12-01</p> <p>As a short-lived climate forcer, <span class="hlt">aerosols</span> exhibit strong radiative effects that vary significantly across the space and time. Current understanding of the long-term variability of <span class="hlt">aerosol</span> climate forcings is however very poor due to lack of relevant atmospheric measurements. Historic records for visibility measurements from thousands of ground meteorological stations offer a plausible tool to study the decadal and multi-decadal variability of <span class="hlt">aerosol</span> radiative effects. As a first step, this study presents a method to estimate <span class="hlt">aerosol</span> direct radiative effect over China based on visibility data for 2006. Visibility data from about 400 ground stations are converted to near-surface <span class="hlt">aerosol</span> extinction coefficients, which are converted then to <span class="hlt">aerosol</span> optical depth (AOD) based on spatially and temporally varying vertical distributions of <span class="hlt">aerosol</span> optical properties simulated by the widely used chemical transport model GEOS-Chem. The resulting AOD data are consistent with direct measurements from the China <span class="hlt">Aerosol</span> Remote Sensing Network (CARSNET) and the <span class="hlt">Aerosol</span> Robotic Network (AERONET) in regions where visibility and AOD measurement sites are close in distance. Next, the visibility-derived AOD data are combined with other <span class="hlt">aerosol</span> optical properties adopted from GEOS-Chem, cloud data from ground stations and surface albedo data from moderate-resolution <span class="hlt">imaging</span> spectroradiometer (MODIS) to derive the direct radiative effect, by employing the Santa Barbara DISORT Atmospheric Radiative Transfer model (SBDART). Spatial and monthly variations of <span class="hlt">aerosol</span> radiative effects are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9259E..0ZL','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9259E..0ZL"><span id="translatedtitle">Investigation of <span class="hlt">aerosol</span> optical properties for remote sensing through DRAGON (distributed regional <span class="hlt">aerosol</span> gridded observation networks) campaign in Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, Jae-Hyun; Ahn, Joon Young; Park, Jin-Soo; Hong, You-Deok; Han, Jin-Seok; Kim, Jhoon; Kim, Sang-Woo</p> <p>2014-11-01</p> <p><span class="hlt">Aerosols</span> in the atmosphere, including dust and pollutants, scatters/absorbs solar radiation and change the microphysics of clouds, thus influencing the Earth's energy budget, climate, air quality, visibility, agriculture and water circulation. Pollutants have also been reported to threaten the human health. The present research collaborated with the U.S. NASA and the U.S. <span class="hlt">Aerosol</span> Robotic Network (AERONET) is to study the <span class="hlt">aerosol</span> characteristics in East Asia and improve the long-distance transportation monitoring technology by analyzing the observations of <span class="hlt">aerosol</span> characteristics in East Asia during Distributed Regional <span class="hlt">Aerosol</span> Gridded Observation Networks (DRAGON) Campaign (March 2012-May 2012). The sun photometers that measure the <span class="hlt">aerosol</span> optical characteristics were placed evenly throughout the Korean Peninsula and concentrated in Seoul and the metropolitan area. Observation data are obtained from the DRAGON campaign and the first year (2012) observation data (<span class="hlt">aerosol</span> optical depth and <span class="hlt">aerosol</span> spatial distribution) are analyzed. Sun photometer observations, including <span class="hlt">aerosol</span> optical depth (AOD), are utilized to validate satellite observations from Geostationary Ocean Color <span class="hlt">Imager</span> (GOCI) and Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS). Additional analysis is performed associated with the Northeast Asia, the Korean Peninsula in particular, to determine the spatial distribution of the <span class="hlt">aerosol</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5271142','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/5271142"><span id="translatedtitle"><span class="hlt">Aerosol</span> distribution apparatus</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Hanson, W.D.</p> <p></p> <p>An apparatus for uniformly distributing an <span class="hlt">aerosol</span> to a plurality of filters mounted in a plenum, wherein the <span class="hlt">aerosol</span> and air are forced through a manifold system by means of a jet pump and released into the plenum through orifices in the manifold. The apparatus allows for the simultaneous <span class="hlt">aerosol</span>-testing of all the filters in the plenum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/6283819','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/6283819"><span id="translatedtitle">Improved solid <span class="hlt">aerosol</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Prescott, D.S.; Schober, R.K.; Beller, J.</p> <p>1988-07-19</p> <p>An improved solid <span class="hlt">aerosol</span> generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid <span class="hlt">aerosol</span> generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated <span class="hlt">aerosol</span> in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/868192','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/868192"><span id="translatedtitle">Solid <span class="hlt">aerosol</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Prescott, Donald S.; Schober, Robert K.; Beller, John</p> <p>1992-01-01</p> <p>An improved solid <span class="hlt">aerosol</span> generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid <span class="hlt">aerosol</span> generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated <span class="hlt">aerosol</span> in a grounded, conical heating chamber, achieving high recovery and flow rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7273153','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7273153"><span id="translatedtitle">Solid <span class="hlt">aerosol</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Prescott, D.S.; Schober, R.K.; Beller, J.</p> <p>1992-03-17</p> <p>An improved solid <span class="hlt">aerosol</span> generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration is disclosed. The improved solid <span class="hlt">aerosol</span> generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated <span class="hlt">aerosol</span> in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=376441','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=376441"><span id="translatedtitle"><span class="hlt">Aerosol</span> Inoculator for Exposure of Human Volunteers</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gerone, Peter J.; Couch, Robert B.; Knight, Vernon</p> <p>1971-01-01</p> <p>The performance of an <span class="hlt">aerosol</span> inoculator for human volunteers is described in tests that used the PR8 strain of type A influenza virus and sodium fluorescein as a physical tracer. Virus recovery from the <span class="hlt">aerosols</span> was approximately 1% and was unaffected by such variables as prolonged <span class="hlt">aerosolization</span>, total airflow, relative humidity, or method of sampling. The recovery of sodium fluorescein from the <span class="hlt">aerosol</span> was approximately 12% and was influenced by total airflow rates and relative humidity. With this apparatus, it should be possible to deliver reasonably predictable and measurable doses of respiratory viruses to human subjects. The design makes it possible to dismantle the inoculator into its component parts to facilitate portability. <span class="hlt">Images</span> PMID:5132095</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015158','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015158"><span id="translatedtitle">The NASA GEOS-5 <span class="hlt">Aerosol</span> Forecasting System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Colarco, Peter; daSilva, Arlindo; Darmenov, Anton</p> <p>2011-01-01</p> <p>The NASA Goddard Earth Observing System modeling and data assimilation environment (GEOS-5) is maintained by the Global Modeling and Assimilation Office (GMAO) at the NASA Goddard Space Flight Center. Near-realtime meteorological forecasts are produced to support NASA satellite and field missions. We have implemented in this environment an <span class="hlt">aerosol</span> module based on the Goddard Chemistry, <span class="hlt">Aerosol</span>, Radiation, and Transport (GOCART) model. This modeling system has previously been evaluated in the context of hindcasts based on assimilated meteorology. Here we focus on the development and evaluation of the near-realtime forecasting system. We present a description of recent efforts to implement near-realtime biomass burning emissions derived from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) fire radiative power products. We as well present a developing capability for improvement of <span class="hlt">aerosol</span> forecasts by assimilation of <span class="hlt">aerosol</span> information from MODIS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930072879&hterms=boer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dboer','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930072879&hterms=boer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dboer"><span id="translatedtitle"><span class="hlt">Aerosol</span> pattern correlation techniques of wind measurement</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eloranta, Edwin W.</p> <p>1985-01-01</p> <p>This paper reviews the current status of lidar <span class="hlt">image</span> correlation techniques of remote wind measurement. It also examines the potential use of satellite borne lidar global wind measurements using this approach. Lidar systems can easily detect spatial variations in the volume scattering cross section of naturally occurring <span class="hlt">aerosols</span>. Lidar derived RHI, PPI and range-time displays of <span class="hlt">aerosol</span> backscatter have been extensively employed in the study of atmospheric structure. Descriptions of this type of data can be obtained in many references including Kunkel et al. (1977), Kunkel et al. (1980), Boers et al. (1984), Uthe et al. (1980), Melfi et al. (1985) and Browell et al. (1983). It is likely that the first space-borne lidars for atmospheric studies will observe <span class="hlt">aerosol</span> backscatter to measure parameters such as boundary layer depth and cloud height. This paper examines the potential application of these relatively simple <span class="hlt">aerosol</span> backscatter lidars to global wind measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998PhDT.......222B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998PhDT.......222B"><span id="translatedtitle">An investigative study into the effectiveness of using computer-aided instruction (<span class="hlt">CAI</span>) as a laboratory component of college-level biology: A case study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barrett, Joan Beverly</p> <p></p> <p>Community colleges serve the most diverse student populations in higher education. They consist of non-traditional, part-time, older, intermittent, and mobile students of different races, ethnic backgrounds, language preferences, physical and mental abilities, and learning style preferences. Students who are academically challenged may have diverse learning characteristics that are not compatible with the more traditional approaches to the delivery of instruction. With this need come new ways of solving the dilemma, such as Computer-aided Instruction (<span class="hlt">CAI</span>). This case study investigated the use of <span class="hlt">CAI</span> as a laboratory component of college-level biology in a small, rural community college setting. The intent was to begin to fill a void that seems to exist in the literature regarding the role of the faculty in the development and use of <span class="hlt">CAI</span>. In particular, the investigator was seeking to understand the practice and its effectiveness, especially in helping the under prepared student. The case study approach was chosen to examine a specific phenomenon within a single institution. Ethnographic techniques, such as interviewing, documentary analysis, life's experiences, and participant observations were used to collect data about the phenomena being studied. Results showed that the faculty was primarily self-motivated and self-taught in their use of <span class="hlt">CAI</span> as a teaching and learning tool. The importance of faculty leadership and collegiality was evident. Findings showed the faculty confident that expectations of helping students who have difficulties with mathematical concepts have been met and that <span class="hlt">CAI</span> is becoming the most valuable of learning tools. In a traditional college classroom, or practice, time is the constant (semesters) and competence is the variable. In the <span class="hlt">CAI</span> laboratory time became the variable and competence the constant. The use of <span class="hlt">CAI</span> also eliminated hazardous chemicals that were routinely used in the more traditional lab. Outcomes showed that annual savings</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRD..120.4248K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRD..120.4248K"><span id="translatedtitle">An analysis of global <span class="hlt">aerosol</span> type as retrieved by MISR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kahn, Ralph A.; Gaitley, Barbara J.</p> <p>2015-05-01</p> <p>In addition to <span class="hlt">aerosol</span> optical depth (AOD), <span class="hlt">aerosol</span> type is required globally for climate forcing calculations, constraining <span class="hlt">aerosol</span> transport models and other applications. However, validating satellite <span class="hlt">aerosol</span>-type retrievals is more challenging than testing AOD results, because <span class="hlt">aerosol</span> type is a more complex quantity, and ground truth data are far less numerous and generally not as robust. We evaluate the Multiangle <span class="hlt">Imaging</span> Spectroradiometer (MISR) Version 22 <span class="hlt">aerosol</span>-type retrievals by assessing product self-consistency on a regional basis and by making comparisons with general expectation and with the <span class="hlt">Aerosol</span> Robotic Network <span class="hlt">aerosol</span>-type climatology, as available. The results confirm and add detail to the observation that <span class="hlt">aerosol</span>-type discrimination improves dramatically where midvisible AOD exceeds about 0.15 or 0.2. When the <span class="hlt">aerosol</span>-type information content of the observations is relatively low, increased scattering-angle range improves particle-type sensitivity. The MISR standard, operational product discriminates among small, medium, and large particles and exhibits qualitative sensitivity to single-scattering albedo (SSA) under good <span class="hlt">aerosol</span>-type retrieval conditions, providing a categorical <span class="hlt">aerosol</span>-type classification. MISR Ångström exponent deviates systematically from ground truth where particle types missing from the algorithm climatology are present, or where cloud contamination is likely to occur, and SSA tends to be overestimated where absorbing particles are found. We determined that the number of mixtures passing the algorithm acceptance criteria (#SuccMix) represents <span class="hlt">aerosol</span>-type retrieval quality effectively, providing a useful <span class="hlt">aerosol</span>-type quality flag.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26078588','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26078588"><span id="translatedtitle">Monitoring the Impacts of Wildfires on Forest Ecosystems and Public Health in the Exo-Urban Environment Using High-Resolution Satellite <span class="hlt">Aerosol</span> Products from the Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huff, Amy K; Kondragunta, Shobha; Zhang, Hai; Hoff, Raymond M</p> <p>2015-01-01</p> <p>Increasing development of exo-urban environments and the spread of urbanization into forested areas is making humans and forest ecosystems more susceptible to the risks associated with wildfires. Larger and more damaging wildfires are having a negative impact on forest ecosystem services, and smoke from wildfires adversely affects the public health of people living in exo-urban environments. Satellite <span class="hlt">aerosol</span> measurements are valuable tools that can track the evolution of wildfires and monitor the transport of smoke plumes. Operational users, such as air quality forecasters and fire management officials, can use satellite observations to complement ground-based and aircraft measurements of wildfire activity. To date, wildfire applications of satellite <span class="hlt">aerosol</span> products, such as <span class="hlt">aerosol</span> optical depth (AOD), have been limited by the relatively coarse resolution of available AOD data. However, the new Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS) instrument on the Suomi National Polar-orbiting Partnership (S-NPP) satellite has high-resolution AOD that is ideally suited to monitoring wildfire impacts on the exo-urban scale. Two AOD products are available from VIIRS: the 750-m × 750-m nadir resolution Intermediate Product (IP) and the 6-km × 6-km resolution Environmental Data Record product, which is aggregated from IP measurements. True color (red, green, and blue [RGB]) imagery and a smoke mask at 750-m × 750-m resolution are also available from VIIRS as decision aids for wildfire applications; they serve as counterparts to AOD measurements by providing visible information about areas of smoke in the atmosphere. To meet the needs of operational users, who do not have time to process raw data files and need access to VIIRS products in near-real time (NRT), VIIRS AOD and RGB NRT imagery are available from the Infusing satellite Data into Environmental Applications (IDEA) web site. A key feature of IDEA is an interactive visualization tool that allows users to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4460978','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4460978"><span id="translatedtitle">Monitoring the Impacts of Wildfires on Forest Ecosystems and Public Health in the Exo-Urban Environment Using High-Resolution Satellite <span class="hlt">Aerosol</span> Products from the Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS)</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Huff, Amy K; Kondragunta, Shobha; Zhang, Hai; Hoff, Raymond M</p> <p>2015-01-01</p> <p>Increasing development of exo-urban environments and the spread of urbanization into forested areas is making humans and forest ecosystems more susceptible to the risks associated with wildfires. Larger and more damaging wildfires are having a negative impact on forest ecosystem services, and smoke from wildfires adversely affects the public health of people living in exo-urban environments. Satellite <span class="hlt">aerosol</span> measurements are valuable tools that can track the evolution of wildfires and monitor the transport of smoke plumes. Operational users, such as air quality forecasters and fire management officials, can use satellite observations to complement ground-based and aircraft measurements of wildfire activity. To date, wildfire applications of satellite <span class="hlt">aerosol</span> products, such as <span class="hlt">aerosol</span> optical depth (AOD), have been limited by the relatively coarse resolution of available AOD data. However, the new Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS) instrument on the Suomi National Polar-orbiting Partnership (S-NPP) satellite has high-resolution AOD that is ideally suited to monitoring wildfire impacts on the exo-urban scale. Two AOD products are available from VIIRS: the 750-m × 750-m nadir resolution Intermediate Product (IP) and the 6-km × 6-km resolution Environmental Data Record product, which is aggregated from IP measurements. True color (red, green, and blue [RGB]) imagery and a smoke mask at 750-m × 750-m resolution are also available from VIIRS as decision aids for wildfire applications; they serve as counterparts to AOD measurements by providing visible information about areas of smoke in the atmosphere. To meet the needs of operational users, who do not have time to process raw data files and need access to VIIRS products in near-real time (NRT), VIIRS AOD and RGB NRT imagery are available from the Infusing satellite Data into Environmental Applications (IDEA) web site. A key feature of IDEA is an interactive visualization tool that allows users to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUSM.A52F..11C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUSM.A52F..11C"><span id="translatedtitle">Evaluation of an assimilated <span class="hlt">aerosol</span> climatology using AERONET</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Collins, W. D.; Rasch, P. J.; Conley, A.</p> <p>2002-05-01</p> <p>The estimates of multi-wavelength <span class="hlt">aerosol</span> optical depth and optical properties from AERONET represent a valuable data set for evaluating <span class="hlt">aerosol</span> models. We have analyzed the fidelity of a new <span class="hlt">aerosol</span> climatology using the AERONET network. An <span class="hlt">aerosol</span> climatology for 1995-2000 has been created using an <span class="hlt">aerosol</span> assimilation model. The model produces global three-dimensional distributions of major <span class="hlt">aerosol</span> species at six-hourly intervals (Collins et al, 2001; Rasch et al, 2001). The atmospheric state and dynamical fields are obtained from the NCEP meteorological reanalysis for 1979 to the present. The model is adjusted to reduce discrepancies relative to retrievals of <span class="hlt">aerosol</span> optical depth from the AVHRR <span class="hlt">imagers</span> on board NOAA polar-orbiting satellites. While these adjustments improve the realism of modeled optical depths over ocean regions (e.g., Collins et al, 2001), the satellite observations do not constrain the model over continental surfaces close to major <span class="hlt">aerosol</span> source regions. We compare the predictions of the assimilation model to selected AERONET observations of <span class="hlt">aerosol</span> optical depths and single-scattering albedos at multiple wavelengths. The results will be used to improve the treatment of <span class="hlt">aerosol</span> sources and optical properties in subsequent versions of the climatology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007304','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007304"><span id="translatedtitle">Global CALIPSO Observations of <span class="hlt">Aerosol</span> Changes Near Clouds</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Varnai, Tamas; Marshak, Alexander</p> <p>2011-01-01</p> <p>Several recent studies have found that clouds are surrounded by a transition zone of rapidly changing <span class="hlt">aerosol</span> optical properties and particle size. Characterizing this transition zone is important for better understanding <span class="hlt">aerosol</span>-cloud interactions and <span class="hlt">aerosol</span> radiative effects, and also for improving satellite retrievals of <span class="hlt">aerosol</span> properties. This letter presents a statistical analysis of a monthlong global data set of Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar observations over oceans. The results show that the transition zone is ubiquitous over all oceans and extends up to 15 km away from clouds. They also show that near-cloud enhancements in backscatter and particle size are strongest at low altitudes, slightly below the top of the nearest clouds. Also, the enhancements are similar near illuminated and shadowy cloud sides, which confirms that the asymmetry of Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer reflectances found in an earlier study comes from 3-D radiative processes and not from differences in <span class="hlt">aerosol</span> properties. Finally, the effects of CALIPSO <span class="hlt">aerosol</span> detection and cloud identification uncertainties are discussed. The findings underline the importance of accounting for the transition zone to avoid potential biases in studies of satellite <span class="hlt">aerosol</span> products, <span class="hlt">aerosol</span>-cloud interactions, and <span class="hlt">aerosol</span> direct radiative effects.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeCoA.153..183F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeCoA.153..183F"><span id="translatedtitle">Evidence for an early nitrogen isotopic evolution in the solar nebula from volatile analyses of a <span class="hlt">CAI</span> from the CV3 chondrite NWA 8616</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Füri, Evelyn; Chaussidon, Marc; Marty, Bernard</p> <p>2015-03-01</p> <p>Nitrogen and noble gas (Ne-Ar) abundances and isotope ratios, determined by CO2 laser extraction static mass spectrometry analysis, as well as Al-Mg and O isotope data from secondary ion mass spectrometry (SIMS) analyses, are reported for a type B calcium-aluminum-rich inclusion (<span class="hlt">CAI</span>) from the CV3 chondrite NWA 8616. The high (26Al/27Al)i ratio of (5.06 ± 0.50) × 10-5 dates the last melting event of the <span class="hlt">CAI</span> at 39-99+109ka after "time zero", limiting the period during which high-temperature exchanges between the <span class="hlt">CAI</span> and the nebular gas could have occurred to a very short time interval. Partial isotopic exchange with a 16O-poor reservoir resulted in Δ17O > -5‰ for melilite and anorthite, whereas spinel and Al-Ti-pyroxene retain the inferred original 16O-rich signature of the solar nebula (Δ17O ⩽ -20‰). The low 20Ne/22Ne (⩽0.83) and 36Ar/38Ar (⩽0.75) ratios of the <span class="hlt">CAI</span> rule out the presence of any trapped planetary or solar noble gases. Cosmogenic 21Ne and 38Ar abundances are consistent with a cosmic ray exposure (CRE) age of ∼14 to 20 Ma, assuming CR fluxes similar to modern ones, without any evidence for pre-irradiation of the <span class="hlt">CAI</span> before incorporation into the meteorite parent body. Strikingly, the <span class="hlt">CAI</span> contains 1.4-3.4 ppm N with a δ15N value of +8‰ to +30‰. Even after correcting the measured δ15N values for cosmogenic 15N produced in situ, the <span class="hlt">CAI</span> is highly enriched in 15N compared to the protosolar nebula (δ15NPSN = -383 ± 8‰; Marty et al., 2011), implying that the <span class="hlt">CAI</span>-forming region was contaminated by 15N-rich material within the first 0.15 Ma of Solar System history, or, alternatively, that the <span class="hlt">CAI</span> was ejected into the outer Solar System where it interacted with a 15N-rich reservoir.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014M%26PS...49..812F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014M%26PS...49..812F"><span id="translatedtitle">Hydrothermal origin of hexagonal CaAl2Si2O8 (dmisteinbergite) in a compact type A <span class="hlt">CAI</span> from the Northwest Africa 2086 CV3 chondrite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fintor, Krisztian; Park, Changkun; Nagy, Szabolcs; Pál-Molnár, Elemér; Krot, Alexander N.</p> <p>2014-05-01</p> <p>We report an occurrence of hexagonal CaAl2Si2O8 (dmisteinbergite) in a compact type A calcium-aluminum-rich inclusion (<span class="hlt">CAI</span>) from the CV3 (Vigarano-like) carbonaceous chondrite Northwest Africa 2086. Dmisteinbergite occurs as approximately 10 μm long and few micrometer-thick lath-shaped crystal aggregates in altered parts of the <span class="hlt">CAI</span>, and is associated with secondary nepheline, sodalite, Ti-poor Al-diopside, grossular, and Fe-rich spinel. Spinel is the only primary <span class="hlt">CAI</span> mineral that retained its original O-isotope composition (Δ17O ~ -24‰); Δ17O values of melilite, perovskite, and Al,Ti-diopside range from -3 to -11‰, suggesting postcrystallization isotope exchange. Dmisteinbergite, anorthite, Ti-poor Al-diopside, and ferroan olivine have 16O-poor compositions (Δ17O ~ -3‰). We infer that dmisteinbergite, together with the other secondary minerals, formed by replacement of melilite as a result of fluid-assisted thermal metamorphism experienced by the CV chondrite parent asteroid. Based on the textural appearance of dmisteinbergite in NWA 2086 and petrographic observations of altered <span class="hlt">CAIs</span> from the Allende meteorite, we suggest that dmisteinbergite is a common secondary mineral in <span class="hlt">CAIs</span> from the oxidized Allende-like CV3 chondrites that has been previously misidentified as a secondary anorthite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SPIE.9882E..18T&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016SPIE.9882E..18T&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Aerosol</span>-cloud interactions: effect on precipitation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takle, Jasmine; Maheskumar, R.</p> <p>2016-05-01</p> <p><span class="hlt">Aerosols</span> are tiny suspended particle in the atmosphere with high variability in time and space, play a major role in modulating the cloud properties and thereby precipitation. To understand the <span class="hlt">aerosol</span> induced Invigoration effect predictors like <span class="hlt">aerosol</span> optical depth, cloud optical depth, cloud top temperature, cloud effective radii, ice water path, retrieved from the Moderate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) level-3 aqua satellite data were analysed for pre monsoon April-May and post monsoon October-November months over the Indian subcontinent 8 ° N to 33° N, 65 °E to 100 °E during the period 2003-2013. Apart from the above data, mesoscale dynamical parameters such as vertical wind shear of horizontal wind, relative humidity, were also considered to understand their role in invigoration. Case studies have been carried out for the regions having heavy rainfall events & minimal rainfall events during high <span class="hlt">Aerosol</span> optical depths occasions respectively. Analysis revealed that the heavy rainfall which occurred in this region with higher optical depths might be due to invigoration effect of <span class="hlt">aerosols</span> wherein the dynamical as well as thermodynamical parameters were also found favourable. Minimal rainfall events were also observed most probably due to the suppression of rain formation/delay in precipitation due to high amount of <span class="hlt">aerosol</span> concentration in these regions. Prominent 36 such cases were studied all over India during Pre & Post monsoon months.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6238W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6238W"><span id="translatedtitle">Development the EarthCARE <span class="hlt">aerosol</span> classification scheme</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wandinger, Ulla; Baars, Holger; Hünerbein, Anja; Donovan, Dave; van Zadelhoff, Gerd-Jan; Fischer, Jürgen; von Bismarck, Jonas; Eisinger, Michael; Lajas, Dulce; Wehr, Tobias</p> <p>2015-04-01</p> <p>The Earth Clouds, <span class="hlt">Aerosols</span> and Radiation Explorer (EarthCARE) mission is a joint ESA/JAXA mission planned to be launched in 2018. The multi-sensor platform carries a cloud-profiling radar (CPR), a high-spectral-resolution cloud/<span class="hlt">aerosol</span> lidar (ATLID), a cloud/<span class="hlt">aerosol</span> multi-spectral <span class="hlt">imager</span> (MSI), and a three-view broad-band radiometer (BBR). Three out of the four instruments (ATLID, MSI, and BBR) will be able to sense the global <span class="hlt">aerosol</span> distribution and contribute to the overarching EarthCARE goals of sensor synergy and radiation closure with respect to <span class="hlt">aerosols</span>. The high-spectral-resolution lidar ATLID obtains profiles of particle extinction and backscatter coefficients, lidar ratio, and linear depolarization ratio as well as the <span class="hlt">aerosol</span> optical thickness (AOT) at 355 nm. MSI provides AOT at 670 nm (over land and ocean) and 865 nm (over ocean). Next to these primary observables the <span class="hlt">aerosol</span> type is one of the required products to be derived from both lidar stand-alone and ATLID-MSI synergistic retrievals. ATLID measurements of the <span class="hlt">aerosol</span> intensive properties (lidar ratio, depolarization ratio) and ATLID-MSI observations of the spectral AOT will provide the basic input for <span class="hlt">aerosol</span>-type determination. <span class="hlt">Aerosol</span> typing is needed for the quantification of anthropogenic versus natural <span class="hlt">aerosol</span> loadings of the atmosphere, the investigation of <span class="hlt">aerosol</span>-cloud interaction, assimilation purposes, and the validation of atmospheric transport models which carry components like dust, sea salt, smoke and pollution. Furthermore, <span class="hlt">aerosol</span> classification is a prerequisite for the estimation of direct <span class="hlt">aerosol</span> radiative forcing and radiative closure studies. With an appropriate underlying microphysical particle description, the categorization of <span class="hlt">aerosol</span> observations into predefined <span class="hlt">aerosol</span> types allows us to infer information needed for the calculation of shortwave radiative effects, such as mean particle size, single-scattering albedo, and spectral conversion factors. In order to ensure</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2002/of02-302/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2002/of02-302/"><span id="translatedtitle">Thermal maturity patterns (<span class="hlt">CAI</span> and %R) in the Ordovician and Devonian rocks of the Appalachian basin in Pennsylvania</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Repetski, John E.; Ryder, Robert T.; Harper, John A.; Trippi, Michael H.</p> <p>2002-01-01</p> <p>The objective of this study is to enhance existing thermal maturity maps in Pennsylvania by establishing: 1) new subsurface <span class="hlt">CAI</span> data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Group are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones (Ryder and others, 1998) and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved <span class="hlt">CAI</span>-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70028484','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70028484"><span id="translatedtitle">Thermal maturity patterns in the Ordovician and Devonian of Pennsylvania using conodont color alteration index (<span class="hlt">CAI</span>) and vitrinite reflectance (%Ro)</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Repetski, J.E.; Ryder, R.T.; Harper, J.A.; Trippi, M.H.</p> <p>2006-01-01</p> <p>This new series of maps enhances previous thermal maturity maps in Pennsylvania by establishing: 1) new subsurface <span class="hlt">CAI</span> data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Group are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved <span class="hlt">CAI</span>-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21633079','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21633079"><span id="translatedtitle">In dialyzed squid axons oxidative stress inhibits the Na+/Ca2+ exchanger by impairing the <span class="hlt">Cai</span>2+-regulatory site.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>DiPolo, Reinaldo; Beaugé, Luis</p> <p>2011-09-01</p> <p>The Na(+)/Ca(2+) exchanger, a major mechanism by which cells extrude calcium, is involved in several physiological and physiopathological interactions. In this work we have used the dialyzed squid giant axon to study the effects of two oxidants, SIN-1-buffered peroxynitrite and hydrogen peroxide (H(2)O(2)), on the Na(+)/Ca(2+) exchanger in the absence and presence of MgATP upregulation. The results show that oxidative stress induced by peroxynitrite and hydrogen peroxide inhibits the Na(+)/Ca(2+) exchanger by impairing the intracellular Ca(2+) (<span class="hlt">Ca(i</span>)(2+))-regulatory sites, leaving unharmed the intracellular Na(+)- and Ca(2+)-transporting sites. This effect is efficiently counteracted by the presence of MgATP and by intracellular alkalinization, conditions that also protect H(i)(+) and (H(i)(+) + Na(i)(+)) inhibition of <span class="hlt">Ca(i</span>)(2+)-regulatory sites. In addition, 1 mM intracellular EGTA reduces oxidant inhibition. However, once the effects of oxidants are installed they cannot be reversed by either MgATP or EGTA. These results have significant implications regarding the role of the Na(+)/Ca(2+) exchanger in response to pathological conditions leading to tissue ischemia-reperfusion and anoxia/reoxygenation; they concur with a marked reduction in ATP concentration, an increase in oxidant production, and a rise in intracellular Ca(2+) concentration that seems to be the main factor responsible for cell damage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014MS%26E...64a2009N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014MS%26E...64a2009N"><span id="translatedtitle">Compression-after-impact (<span class="hlt">CAI</span>) performance of epoxycarbon fibre-reinforced nanocomposites using nanosilica and rubber particle enhancement</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nikfar, B.; Njuguna, J.</p> <p>2014-08-01</p> <p>One of the problems in the design of automotive structures and body parts made by fibre reinforced composites is that these materials are susceptible to a small energy impact caused by for instance, accidental tool drop during maintenance or stone strike while in operation. This often lead to a barely visible impact damage which causes reduction in compressive strength of the composite part. To increase the impact tolerance of the composites, toughening agents like silica nanoparticles and rubber particles can be utilized to toughen the resin. To understand the effect of the particles enhancement, the impact tolerance was evaluated utilizing Compression After Impact (<span class="hlt">CAI</span>) test after the impact induced by gas- gun impacting equipment. The results from <span class="hlt">CAI</span> test after 20 J impact (high energy stone strike) shows about 30% improvement in residual compressive strength for the nanosilica enhanced composite compared to unmodified CFRP. Also C-scan results after 7 J impact shows about 50% smaller delamination area for the nano-enhanced composite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2005/1078/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2005/1078/"><span id="translatedtitle">Thermal maturity patterns (<span class="hlt">CAI</span> and %Ro) in the Ordovician and Devonian rocks of the Appalachian basin in West Virginia</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Repetski, John E.; Ryder, Robert T.; Avary, Katharine Lee; Trippi, Michael H.</p> <p>2005-01-01</p> <p>The objective of this study is to enhance existing thermal maturity maps in West Virginia by establishing: 1) new subsurface <span class="hlt">CAI</span> data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Limestone are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones (Ryder and others, 1998) and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved <span class="hlt">CAI</span>-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.6195O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.6195O"><span id="translatedtitle">Halogen-induced organic <span class="hlt">aerosol</span> (XOA) formation and decarboxylation of carboxylic acids by reactive halogen species - a time-resolved <span class="hlt">aerosol</span> flow-reactor study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ofner, Johannes; Zetzsch, Cornelius</p> <p>2013-04-01</p> <p>Reactive halogen species (RHS) are released to the atmosphere from various sources like photo-activated sea-salt <span class="hlt">aerosol</span> and salt lakes. Recent studies (<span class="hlt">Cai</span> et al., 2006 and 2008, Ofner et al., 2012) indicate that RHS are able to interact with SOA precursors similarly to common atmospheric oxidizing gases like OH radicals and ozone. The reaction of RHS with SOA precursors like terpenes forms so-called halogen-induced organic <span class="hlt">aerosol</span> (XOA). On the other hand, RHS are also able to change the composition of functional groups, e.g. to initiate the decarboxylation of carboxylic acids (Ofner et al., 2012). The present study uses a 50 cm <span class="hlt">aerosol</span> flow-reactor, equipped with a solar simulator to investigate the time-resolved evolution and transformation of vibrational features in the mid-infrared region. The <span class="hlt">aerosol</span> flow-reactor is coupled to a home-made multi-reflection cell (Ofner et al., 2010), integrated into a Bruker IFS 113v FTIR spectrometer. The reactor is operated with an inlet feed (organic compound) and a surrounding feed (reactive halogen species). The moveable inlet of the flow reactor allows us to vary reaction times between a few seconds and up to about 3 minutes. Saturated vapours of different SOA precursors and carboxylic acids were fed into the flow reactor using the moveable inlet. The surrounding feed inside the flow reactor was a mixture of zero air with molecular chlorine as the precursor for the formation of reactive halogen species. Using this setup, the formation of halogen-induced organic <span class="hlt">aerosol</span> could be monitored with a high time resolution using FTIR spectroscopy. XOA formation is characterized by hydrogen-atom abstraction, carbon-chlorine bond formation and later, even formation of carboxylic acids. Several changes of the entire structure of the organic precursor, caused by the reaction of RHS, are visible. While XOA formation is a very fast process, the decarboxylation of carboxylic acids, induced by RHS is rather slow. However, XOA formation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980201315','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980201315"><span id="translatedtitle">Radiative Effects of <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Valero, Francisco P. J.</p> <p>1997-01-01</p> <p>During the Atlantic Stratocumulus Transition Experiment (ASTEX) in June 1992, two descents in cloud-free regions allowed comparison of the change in <span class="hlt">aerosol</span> optical depth as determined by an onboard total-direct-diffuse radiometer (TDDR) to the change calculated from measured size resolved <span class="hlt">aerosol</span> microphysics and chemistry. Both profiles included pollution haze layer from Europe but the second also included the effect of a Saharan dust layer above the haze. The separate contributions of supermicrometer (coarse) and submicrometer (fine) <span class="hlt">aerosol</span> were determined and thermal analysis of the pollution haze indicated that the fine <span class="hlt">aerosol</span> was composed primarily of a sulfate/water mixture with a refractory soot-like core.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780007267','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780007267"><span id="translatedtitle">Thermoluminescent <span class="hlt">aerosol</span> analysis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rogowski, R. S.; Long, E. R., Jr. (Inventor)</p> <p>1977-01-01</p> <p>A method for detecting and measuring trace amounts of <span class="hlt">aerosols</span> when reacted with ozone in a gaseous environment was examined. A sample <span class="hlt">aerosol</span> was exposed to a fixed ozone concentration for a fixed period of time, and a fluorescer was added to the exposed sample. The sample was heated in a 30 C/minute linear temperature profile to 200 C. The trace peak was measured and recorded as a function of the test <span class="hlt">aerosol</span> and the recorded thermoluminescence trace peak of the fluorescer is specific to the <span class="hlt">aerosol</span> being tested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.A13F..03P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.A13F..03P"><span id="translatedtitle">Global <span class="hlt">Aerosol</span> Radiative Forcing using Satellite and Surface Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patadia, F.; Christopher, S. A.</p> <p>2007-12-01</p> <p>Over the industrial period, <span class="hlt">aerosols</span> have increased due to human activities and their effects on climate are the largest source of uncertainty in the current IPCC estimates of global climate forcing due to human activities. Inhomogeneous distribution of <span class="hlt">aerosols</span> in space and time poses a challenge in their characterization and requires global measurements to assess their effects and reduce the associated uncertainties. In this paper we use global measurements from both satellite and ground based observations for one year time period to estimate the shortwave <span class="hlt">aerosol</span> radiative forcing (SWARF) at the top-of-atmosphere (TOA) and discuss the associated uncertainties. For this, <span class="hlt">aerosol</span> properties (optical depth) derived from <span class="hlt">AErosol</span> RObotic NETwork (AERONET), a federation of ground-based remote sensing instruments, are used in this paper in conjunction with measurements of the TOA shortwave flux from CERES instrument (onboard Terra satellite). High spectral and spatial resolution observations from <span class="hlt">Imager</span> (MODIS) will be used to identify clear sky conditions within CERES foot print and GOCART results will also be used for separating <span class="hlt">aerosol</span> types. Global <span class="hlt">aerosol</span> forcing and corresponding radiative forcing efficiencies will be presented as a function of major <span class="hlt">aerosol</span> types [including anthropogenic (sulfate, soot, black carbon) and natural (dust) <span class="hlt">aerosols</span>], region and season. This study should serve as a useful constraint for both numerical modeling simulations and satellite based estimates of SWARF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUSM.A33E..07P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUSM.A33E..07P"><span id="translatedtitle">Global <span class="hlt">Aerosol</span> Radiative Forcing Using Satellite and Surface Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patadia, F.; Christopher, S. A.</p> <p>2008-05-01</p> <p>Over the industrial period, <span class="hlt">aerosols</span> have increased due to human activities and their effects on climate are the largest source of uncertainty in the current IPCC estimates of global climate forcing due to human activities. Inhomogeneous distribution of <span class="hlt">aerosols</span> in space and time poses a challenge in characterizing their properties and requires global measurements to assess their effects and reduce the associated uncertainties. In this paper we use global measurements from both satellite and ground based observations for one year time period to estimate the shortwave <span class="hlt">aerosol</span> radiative forcing (SWARF) at the top-of-atmosphere (TOA) and discuss the associated uncertainties. For this, <span class="hlt">aerosol</span> properties (optical depth) derived from <span class="hlt">AErosol</span> RObotic NETwork (AERONET), a federation of ground-based remote sensing instruments, are used in this paper in conjunction with measurements of the TOA shortwave flux from CERES instrument (onboard Terra satellite). High spectral and spatial resolution observations from <span class="hlt">Imager</span> (MODIS) is used to identify clear sky conditions within CERES foot print and GOCART results will also be used for separating <span class="hlt">aerosol</span> types. Global <span class="hlt">aerosol</span> forcing and corresponding radiative forcing efficiencies will be presented as a function of major <span class="hlt">aerosol</span> types [including anthropogenic (sulfate, soot, black carbon) and natural (dust) <span class="hlt">aerosols</span>], region and season. This study should serve as a useful constraint for both numerical modeling simulations and satellite based estimates of SWARF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A31D0080M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A31D0080M"><span id="translatedtitle">The Retrieval of <span class="hlt">Aerosol</span> Optical Thickness Using the MERIS Instrument</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mei, L.; Rozanov, V. V.; Vountas, M.; Burrows, J. P.; Levy, R. C.; Lotz, W.</p> <p>2015-12-01</p> <p>Retrieval of <span class="hlt">aerosol</span> properties for satellite instruments without shortwave-IR spectral information, multi-viewing, polarization and/or high-temporal observation ability is a challenging problem for spaceborne <span class="hlt">aerosol</span> remote sensing. However, space based instruments like the MEdium Resolution <span class="hlt">Imaging</span> Spectrometer (MERIS) and the successor, Ocean and Land Colour Instrument (OLCI) with high calibration accuracy and high spatial resolution provide unique abilities for obtaining valuable <span class="hlt">aerosol</span> information for a better understanding of the impact of <span class="hlt">aerosols</span> on climate, which is still one of the largest uncertainties of global climate change evaluation. In this study, a new <span class="hlt">Aerosol</span> Optical Thickness (AOT) retrieval algorithm (XBAER: eXtensible Bremen <span class="hlt">AErosol</span> Retrieval) is presented. XBAER utilizes the global surface spectral library database for the determination of surface properties while the MODIS collection 6 <span class="hlt">aerosol</span> type treatment is adapted for the <span class="hlt">aerosol</span> type selection. In order to take the surface Bidirectional Reflectance Distribution Function (BRDF) effect into account for the MERIS reduce resolution (1km) retrieval, a modified Ross-Li mode is used. The AOT is determined in the algorithm using lookup tables including polarization created using Radiative Transfer Model SCIATRAN3.4, by minimizing the difference between atmospheric corrected surface reflectance with given AOT and the surface reflectance calculated from the spectral library. The global comparison with operational MODIS C6 product, Multi-angle <span class="hlt">Imaging</span> SpectroRadiometer (MISR) product, Advanced Along-Track Scanning Radiometer (AATSR) <span class="hlt">aerosol</span> product and the validation using <span class="hlt">AErosol</span> RObotic NETwork (AERONET) show promising results. The current XBAER algorithm is only valid for <span class="hlt">aerosol</span> remote sensing over land and a similar method will be extended to ocean later.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A13K0337B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A13K0337B"><span id="translatedtitle">Comparison of <span class="hlt">Aerosol</span> Classification from Airborne High Spectral Resolution Lidar and the CALIPSO Vertical Feature Mask</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burton, S. P.; Ferrare, R. A.; Omar, A. H.; Hostetler, C. A.; Hair, J. W.; Rogers, R.; Obland, M. D.; Butler, C. F.; Cook, A. L.; Harper, D. B.</p> <p>2012-12-01</p> <p> applications. The HSRL products are used to apportion AOT by type and vertical location in the column, and to characterize the frequency of cases where multiple types are present in the column. Resolving scenes with multiple types in the column is not possible with passive <span class="hlt">imaging</span> radiometer and polarimeter measurements. The HSRL <span class="hlt">aerosol</span> type also has higher resolution than the CALIPSO layer-wise product and provides insight into the performance of CALIPSO layer separation. Information about the vertical distribution of <span class="hlt">aerosol</span> types is useful for estimating radiative forcing, understanding <span class="hlt">aerosol</span> lifetime and transport, and assessing the predictions of transport models. CALIPSO has been a pathfinder, providing the first long-term global data set of <span class="hlt">aerosol</span> vertical distribution. Based on our results, a future satellite lidar similar to CALIPSO, but with the addition of polarization sensitivity at 1064 nm and the HSRL technique at 532 nm, could provide a significant advance in characterizing the vertical distribution of <span class="hlt">aerosol</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED115225.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED115225.pdf"><span id="translatedtitle">Evaluation of the Experimental <span class="hlt">CAI</span> Network (1973-1975) of the Lister Hill National Center for Biomedical Communications, National Library of Medicine. Final Report. No. ED-75-1.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Rubin, Martin L.; And Others</p> <p></p> <p>An evaluation was made of the biomedical Computer Assisted Instruction (<span class="hlt">CAI</span>) Network Experiment, established by the National Library of Medicine in 1973 to test the feasibility of sharing <span class="hlt">CAI</span> learning materials through a national computer network. The evaluation was designed to assist decision makers in planning a future mechanism for distributing…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmEn.141..532B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmEn.141..532B"><span id="translatedtitle"><span class="hlt">Aerosol</span> types and radiative forcing estimates over East Asia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhawar, Rohini L.; Lee, Woo-Seop; Rahul, P. R. C.</p> <p>2016-09-01</p> <p>Using the CALIPSO (Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observations) and MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) satellite data sets along with the CSIRO-MK 3.6.0 model simulations, we analyzed the <span class="hlt">aerosol</span> optical depth (AOD) variability during March-May (MAM), June-August (JJA) along with their annual mean variability over East Asia for the period 2006-2012. The CALIPSO measurements correlated well with the MODIS measurements and the CSIRO-MK 3.6.0 model simulations over the spatial distribution patterns of the <span class="hlt">aerosols</span>, but CALIPSO underestimated the magnitudes of the AOD. Maximum smoke <span class="hlt">aerosol</span> loading is observed to occur during JJA, as a result of wind transport from Southern China while dust loading dominated during MAM via the transport from desert region. The vertical distribution profiles revealed that there is uniform distribution of smoke <span class="hlt">aerosols</span> during both MAM and JJA, only differing at the altitude at which they peak; while the dust <span class="hlt">aerosols</span> during MAM showed a significant distribution from the surface to 10 km altitude and JJA was marked with lower dust loading at the same altitudes. Both dust and smoke <span class="hlt">aerosols</span> warm the atmosphere in MAM but due to the absorbing nature of smoke <span class="hlt">aerosols</span>, they cause considerable cooling at the surface which is double when compared to the dust <span class="hlt">aerosols</span>. The top of the atmosphere <span class="hlt">aerosol</span> radiative forcing (ARF) due to smoke and dust <span class="hlt">aerosols</span> is positive in MAM which indicates warming over East Asia. During MAM a consistent declining trend of the surface ARF due to smoke <span class="hlt">aerosols</span> persisted over the last three decades as conspicuously evidenced from model analysis; the decline is ∼10 W/m2 from 1980 to 2012.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007AGUFM.A53C1340T&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007AGUFM.A53C1340T&link_type=ABSTRACT"><span id="translatedtitle">Does the Madden-Julian Oscillation Influence <span class="hlt">Aerosol</span> Variability?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tian, B.; Waliser, D. E.; Kahn, R. A.; Li, Q.; Yung, Y. L.; Tyranowski, T.; Geogdzhayev, I. V.; Mishchenko, M. I.; Torres, O.; Smirnov, A.</p> <p>2007-12-01</p> <p>We investigate the modulation of <span class="hlt">aerosols</span> by the Madden-Julian Oscillation (MJO) using satellite-based global <span class="hlt">aerosol</span> products, including <span class="hlt">aerosol</span> index (AI) from the Total Ozone Mapping Spectrometer (TOMS) on Nimbus-7, and <span class="hlt">aerosol</span> optical thickness (AOT) from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) on Terra and Aqua and the Advanced Very High Resolution Radiometer (AVHRR) on NOAA satellites. A composite analysis is performed for boreal winter, and the global pentad rainfall data from the NOAA Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) are used to identify MJO events. The MJO composites exhibit large variations in the TOMS AI and MODIS/AVHRR AOT over the equatorial Indian and western Pacific Oceans where MJO convection is active, as well as the tropical Africa and Atlantic Ocean where MJO convection is relatively weak but the background <span class="hlt">aerosol</span> level is relatively high. A strong inverse linear relationship between the TOMS AI and rainfall anomalies, but a weaker, less coherent positive correlation between the MODIS/AVHRR AOT and rainfall anomalies, were found. The <span class="hlt">Aerosol</span> Robotic Network AOT pattern at Kaashidoo (73.5°E, 4.9°N) and Nauru (167°E, 0.5°S) is more consistent with MODIS and AVHRR. These results indicate a connection between the MJO, its associated rainfall and circulation variability, and the observed <span class="hlt">aerosol</span> variations. Several physical and non-physical factors that may contribute to the observed <span class="hlt">aerosol</span>-rainfall relationship, such as <span class="hlt">aerosol</span> humidification effect, wet deposition, surface wind speed, phytoplankton, different sensor sensitivities (absorbing versus non-absorbing <span class="hlt">aerosols</span> and upper versus lower tropospheric <span class="hlt">aerosols</span>), sampling issue, and cloud contamination, are discussed. However, a clear causal explanation for the observed patterns remains elusive. Further investigation is needed to unravel this complex <span class="hlt">aerosol</span>-rainfall relationship.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/880369','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/880369"><span id="translatedtitle">Portable <span class="hlt">Aerosol</span> Contaminant Extractor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Carlson, Duane C.; DeGange, John J.; Cable-Dunlap, Paula</p> <p>2005-11-15</p> <p>A compact, portable, <span class="hlt">aerosol</span> contaminant extractor having ionization and collection sections through which ambient air may be drawn at a nominal rate so that <span class="hlt">aerosol</span> particles ionized in the ionization section may be collected on charged plate in the collection section, the charged plate being readily removed for analyses of the particles collected thereon.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eosweb.larc.nasa.gov/project/misr/gallery/global_aerosol_observations','SCIGOV-ASDC'); return false;" href="https://eosweb.larc.nasa.gov/project/misr/gallery/global_aerosol_observations"><span id="translatedtitle">Global <span class="hlt">Aerosol</span> Observations</span></a></p> <p><a target="_blank" href="http://eosweb.larc.nasa.gov/">Atmospheric Science Data Center </a></p> <p></p> <p>2013-04-19</p> <p>... atmosphere, directly influencing global climate and human health. Ground-based networks that accurately measure column <span class="hlt">aerosol</span> amount and ... being used to improve Air Quality Models and for regional health studies. To assess the human-health impact of chronic <span class="hlt">aerosol</span> exposure, ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1169526','SCIGOV-DOEDE'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1169526"><span id="translatedtitle">Direct <span class="hlt">Aerosol</span> Forcing Uncertainty</span></a></p> <p><a target="_blank" href="http://www.osti.gov/dataexplorer">DOE Data Explorer</a></p> <p>Mccomiskey, Allison</p> <p>2008-01-15</p> <p>Understanding sources of uncertainty in <span class="hlt">aerosol</span> direct radiative forcing (DRF), the difference in a given radiative flux component with and without <span class="hlt">aerosol</span>, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: <span class="hlt">aerosol</span> optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual <span class="hlt">aerosol</span> or surface properties, are calculated at three locations representing distinct <span class="hlt">aerosol</span> types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective <span class="hlt">aerosol</span> or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, <span class="hlt">aerosol</span> type, and <span class="hlt">aerosol</span> optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1028099','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1028099"><span id="translatedtitle">Ganges valley <span class="hlt">aerosol</span> experiment.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kotamarthi, V.R.; Satheesh, S.K.</p> <p>2011-08-01</p> <p>In June 2011, the Ganges Valley <span class="hlt">Aerosol</span> Experiment (GVAX) began in the Ganges Valley region of India. The objective of this field campaign is to obtain measurements of clouds, precipitation, and complex <span class="hlt">aerosols</span> to study their impact on cloud formation and monsoon activity in the region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008ARAC....1..485P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008ARAC....1..485P"><span id="translatedtitle">Analysis of Atmospheric <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Prather, Kimberly A.; Hatch, Courtney D.; Grassian, Vicki H.</p> <p>2008-07-01</p> <p><span class="hlt">Aerosols</span> represent an important component of the Earth's atmosphere. Because <span class="hlt">aerosols</span> are composed of solid and liquid particles of varying chemical complexity, size, and phase, large challenges exist in understanding how they impact climate, health, and the chemistry of the atmosphere. Only through the integration of field, laboratory, and modeling analysis can we begin to unravel the roles atmospheric <span class="hlt">aerosols</span> play in these global processes. In this article, we provide a brief review of the current state of the science in the analysis of atmospheric <span class="hlt">aerosols</span> and some important challenges that need to be overcome before they can become fully integrated. It is clear that only when these areas are effectively bridged can we fully understand the impact that atmospheric <span class="hlt">aerosols</span> have on our environment and the Earth's system at the level of scientific certainty necessary to design and implement sound environmental policies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970001690','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970001690"><span id="translatedtitle">Radiative Effects of <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Valero, Francisco P. J.</p> <p>1996-01-01</p> <p>During the Atlantic Stratocumulus Transition Experiment (ASTEX) in June 1992, two descents in cloud-free regions allowed comparison of the change in <span class="hlt">aerosol</span> optical depth as determined by an onboard total-direct-diffuse radiometer (TDDR) to the change calculated from measured size-resolved <span class="hlt">aerosol</span> microphysics and chemistry. Both profiles included a pollution haze from Europe but the second also included the effect of a Saharan dust layer above the haze. The separate contributions of supermicrometer (coarse) and submicrometer (fine) <span class="hlt">aerosol</span> were determined and thermal analysis of the pollution haze indicated that the fine <span class="hlt">aerosol</span> was composed primarily of a sulfate/water mixture with a refractory soot-like core. The soot core increased the calculated extinction by about 10% in the most polluted drier layer relative to a pure sulfate <span class="hlt">aerosol</span> but had significantly less effect at higher humidities. A 3 km descent through a boundary layer air mass dominated by pollutant <span class="hlt">aerosol</span> with relative humidities (RH) 10-77% yielded a close agreement between the measured and calculated <span class="hlt">aerosol</span> optical depths (550 nm) of 0.160 (+/- 0.07) and 0. 157 (+/- 0.034) respectively. During descent the <span class="hlt">aerosol</span> mass scattering coefficient per unit sulfate mass varied from about 5 to 16 m(exp 2)/g and primarily dependent upon ambient RH. However, the total scattering coefficient per total fine mass was far less variable at about 4+/- 0.7 m(exp 2)/g. A subsequent descent through a Saharan dust layer located above the pollution <span class="hlt">aerosol</span> layer revealed that both layers contributed similarly to <span class="hlt">aerosol</span> optical depth. The scattering per unit mass of the coarse aged dust was estimated at 1.1 +/- 0.2 m(exp 2)/g. The large difference (50%) in measured and calculated optical depth for the dust layer exceeded measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24601011','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24601011"><span id="translatedtitle">Aqueous <span class="hlt">aerosol</span> SOA formation: impact on <span class="hlt">aerosol</span> physical properties.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Woo, Joseph L; Kim, Derek D; Schwier, Allison N; Li, Ruizhi; McNeill, V Faye</p> <p>2013-01-01</p> <p>Organic chemistry in <span class="hlt">aerosol</span> water has recently been recognized as a potentially important source of secondary organic <span class="hlt">aerosol</span> (SOA) material. This SOA material may be surface-active, therefore potentially affecting <span class="hlt">aerosol</span> heterogeneous activity, ice nucleation, and CCN activity. Aqueous <span class="hlt">aerosol</span> chemistry has also been shown to be a potential source of light-absorbing products ("brown carbon"). We present results on the formation of secondary organic <span class="hlt">aerosol</span> material in <span class="hlt">aerosol</span> water and the associated changes in <span class="hlt">aerosol</span> physical properties from GAMMA (Gas-<span class="hlt">Aerosol</span> Model for Mechanism Analysis), a photochemical box model with coupled gas and detailed aqueous <span class="hlt">aerosol</span> chemistry. The detailed <span class="hlt">aerosol</span> composition output from GAMMA was coupled with two recently developed modules for predicting a) <span class="hlt">aerosol</span> surface tension and b) the UV-Vis absorption spectrum of the <span class="hlt">aerosol</span>, based on our previous laboratory observations. The simulation results suggest that the formation of oligomers and organic acids in bulk <span class="hlt">aerosol</span> water is unlikely to perturb <span class="hlt">aerosol</span> surface tension significantly. Isoprene-derived organosulfates are formed in high concentrations in acidic <span class="hlt">aerosols</span> under low-NO(x) conditions, but more experimental data are needed before the potential impact of these species on <span class="hlt">aerosol</span> surface tension may be evaluated. Adsorption of surfactants from the gas phase may further suppress <span class="hlt">aerosol</span> surface tension. Light absorption by aqueous <span class="hlt">aerosol</span> SOA material is driven by dark glyoxal chemistry and is highest under high-NO(x) conditions, at high relative humidity, in the early morning hours. The wavelength dependence of the predicted absorption spectra is comparable to field observations and the predicted mass absorption efficiencies suggest that aqueous <span class="hlt">aerosol</span> chemistry can be a significant source of <span class="hlt">aerosol</span> brown carbon under urban conditions. PMID:24601011</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140012070','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140012070"><span id="translatedtitle">Impact of Assimilated and Interactive <span class="hlt">Aerosol</span> on Tropical Cyclogenesis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Reale, O.; Lau, K. M.; daSilva, A.; Matsui, T.</p> <p>2014-01-01</p> <p>This article investigates the impact 3 of Saharan dust on the development of tropical cyclones in the Atlantic. A global data assimilation and forecast system, the NASA GEOS-5, is used to assimilate all satellite and conventional data sets used operationally for numerical weather prediction. In addition, this new GEOS-5 version includes assimilation of <span class="hlt">aerosol</span> optical depth from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS). The analysis so obtained comprises atmospheric quantities and a realistic 3-d <span class="hlt">aerosol</span> and cloud distribution, consistent with the meteorology and validated against Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and CloudSat data. These improved analyses are used to initialize GEOS-5 forecasts, explicitly accounting for <span class="hlt">aerosol</span> direct radiative effects and their impact on the atmospheric dynamics. Parallel simulations with/without <span class="hlt">aerosol</span> radiative effects show that effects of dust on static stability increase with time, becoming highly significant after day 5 and producing an environment less favorable to tropical cyclogenesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006GeCoA..70.2622M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006GeCoA..70.2622M"><span id="translatedtitle">Crystallization of melilite from CMAS-liquids and the formation of the melilite mantle of Type B1 <span class="hlt">CAIs</span>: Experimental simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mendybaev, Ruslan A.; Richter, Frank M.; Davis, Andrew M.</p> <p>2006-05-01</p> <p>Type B <span class="hlt">CAIs</span> are subdivided into B1s, with well-developed melilite mantles, and B2s, with randomly distributed melilite. Despite intensive study, the origin of the characteristic melilite mantle of the B1s remains unclear. Recently, we proposed that formation of the melilite mantle is caused by depletion of the droplet surface in volatile magnesium and silicon due to higher evaporation rates of volatile species compared to their slow diffusion rates in the melt, thus making possible crystallization of melilite at the edge of the <span class="hlt">CAI</span> first, followed by its crystallization in the central parts at lower temperatures. Here, we present the results of an experimental study that aimed to reproduce the texture observed in natural Type B <span class="hlt">CAIs</span>. First, we experimentally determined crystallization temperatures of melilite for three melt compositions, which, combined with literature data, allowed us to find a simple relationship between the melt composition, crystallization temperature, and composition of first crystallizing melilite. Second, we conducted a series of evaporation and cooling experiments exposing <span class="hlt">CAI</span>-like melts to gas mixtures with different oxygen fugacities (f). Cooling of the molten droplets in gases with logf⩾IW-4 resulted in crystallization of randomly distributed melilite, while under more reducing conditions, melilite mantles have been formed. Chemical profiles through samples quenched right before melilite started to crystallize showed no chemical gradients in samples exposed to relatively oxidizing gases (logf⩾IW-4), while the near-surface parts of the samples exposed to very reducing gases (logf⩽IW-7) were depleted in volatile MgO and SiO 2, and enriched in refractory Al 2O 3. Using these experimental results and the fact that the evaporation rate of magnesium and silicon from <span class="hlt">CAI</span>-like melts is proportional to √{P}, we estimate that Type B1 <span class="hlt">CAIs</span> could be formed by evaporation of a partially molten precursor in a gas of solar composition with P</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....9292C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....9292C"><span id="translatedtitle">B and Mg isotopic variations in Leoville mrs-06 type B1 <span class="hlt">cai</span>:origin of 10Be and 26Al</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chaussidon, M.; Robert, F.; Russel, S. S.; Gounelle, M.; Ash, R. D.</p> <p>2003-04-01</p> <p>The finding [1-3] in Ca-Al-rich refractory inclusions (<span class="hlt">CAI</span>) of primitive chondrites of traces of the in situ decay of radioactive 10Be (half-life 1.5Myr) indicates that irradiation of the protosolar nebula by the young Sun in its T-Tauri phase has produced significant amounts of the Li-Be-B elements. This irradiation may have produced also some or all of the short-lived 26Al (half-life 0.7Myr) and 41Ca (half-life 0.1Myr) previously detected in <span class="hlt">CAIs</span>. To constrain the origin of 10Be and 10Al it is important to look for coupled variations in the 10Be/9Be and 26Al/27Al ratios in <span class="hlt">CAIs</span> and to understand the processes responsible for these variations (e.g. variations in the fluences of irradiation, secondary perturbations of the <span class="hlt">CAIs</span>, ...) We have thus studied the Li and B isotopic compositions and the Be/Li and Be/B concentration ratios in one <span class="hlt">CAI</span> (MRS-06) from the Leoville CV3 chondrite in which large variations of the Mg isotopic compositions showing both the in situ decay of 26Al and the secondary redistribution of Mg isotopes have been observed [4]. The results show large variations for the Li and B isotopic compositions (^7Li/^6Li ranging from 11.02±0.21 to 11.82±0.07, and 10B/11B ratios ranging from 0.2457±0.0053 to 0.2980±0.0085). The ^7Li/^6Li ratio tend to decrease towards the rim of the inclusion. The 10B/11B ratios are positively correlated with the ^9Be/11B ratios indicating the in situ decay of 10Be. However perturbations of the 10Be/B system are observed. They would correspond to an event which occurred approximately 2Myr after the formation of the <span class="hlt">CAI</span> and the irradiation of the <span class="hlt">CAI</span> precursors which is responsible for the 10Be observed in the core of the <span class="hlt">CAI</span>. These perturbations seem compatible with those observed for the 26Al/Mg system but they might be due to an irradiation of the already-formed, isolated <span class="hlt">CAI</span> which would have resulted in increased 10Be/^9Be ratios and low ^7Li/^6Li ratios in the margin of the <span class="hlt">CAI</span>. [1] McKeegan K. D. et al. (2000</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17034300','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17034300"><span id="translatedtitle">Generating monodisperse pharmacological <span class="hlt">aerosols</span> using the spinning-top <span class="hlt">aerosol</span> generator.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Biddiscombe, Martyn F; Barnes, Peter J; Usmani, Omar S</p> <p>2006-01-01</p> <p>Pharmacological <span class="hlt">aerosols</span> of precisely controlled particle size and narrow dispersity can be generated using the spinning-top <span class="hlt">aerosol</span> generator (STAG). The ability of the STAG to generate monodisperse <span class="hlt">aerosols</span> from solutions of raw drug compounds makes it a valuable research instrument. In this paper, the versatility of this instrument has been further demonstrated by <span class="hlt">aerosolizing</span> a range of commercially available nebulized pulmonary therapy preparations. Nebules of Flixotide (fluticasone propionate), Pulmicort (budesonide), Combivent (salbutamol sulphate and ipratropium bromide), Bricanyl (terbutaline sulphate), Atrovent(ipratropium bromide), and Salamol (salbutamol sulphate) were each mixed with ethanol and delivered to the STAG. Monodisperse drug <span class="hlt">aerosol</span> distributions were generated with MMADs of 0.95-6.7 microm. To achieve larger particle sizes from the nebulizer drug suspensions, the STAG formed compound particle agglomerates derived from the smaller insoluble drug particles. These compound agglomerates behaved aerodynamically as a single particle, and this was verified using an aerodynamic particle sizer and an Andersen Cascade Impactor. Scanning electron microscope <span class="hlt">images</span> demonstrated their physical structure. On the other hand using the nebulizer drug solutions, spherical particles proportional to the original droplet diameter were generated. The <span class="hlt">aerosols</span> generated by the STAG can allow investigators to study the scientific principles of inhaled drug deposition and lung physiology for a range of therapeutic agents. PMID:17034300</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AtmEn.118..135B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AtmEn.118..135B"><span id="translatedtitle">Sugars in Antarctic <span class="hlt">aerosol</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barbaro, Elena; Kirchgeorg, Torben; Zangrando, Roberta; Vecchiato, Marco; Piazza, Rossano; Barbante, Carlo; Gambaro, Andrea</p> <p>2015-10-01</p> <p>The processes and transformations occurring in the Antarctic <span class="hlt">aerosol</span> during atmospheric transport were described using selected sugars as source tracers. Monosaccharides (arabinose, fructose, galactose, glucose, mannose, ribose, xylose), disaccharides (sucrose, lactose, maltose, lactulose), alcohol-sugars (erythritol, mannitol, ribitol, sorbitol, xylitol, maltitol, galactitol) and anhydrosugars (levoglucosan, mannosan and galactosan) were measured in the Antarctic <span class="hlt">aerosol</span> collected during four different sampling campaigns. For quantification, a sensitive high-pressure anion exchange chromatography was coupled with a single quadrupole mass spectrometer. The method was validated, showing good accuracy and low method quantification limits. This study describes the first determination of sugars in the Antarctic <span class="hlt">aerosol</span>. The total mean concentration of sugars in the <span class="hlt">aerosol</span> collected at the "Mario Zucchelli" coastal station was 140 pg m-3; as for the <span class="hlt">aerosol</span> collected over the Antarctic plateau during two consecutive sampling campaigns, the concentration amounted to 440 and 438 pg m-3. The study of particle-size distribution allowed us to identify the natural emission from spores or from sea-spray as the main sources of sugars in the coastal area. The enrichment of sugars in the fine fraction of the <span class="hlt">aerosol</span> collected on the Antarctic plateau is due to the degradation of particles during long-range atmospheric transport. The composition of sugars in the coarse fraction was also investigated in the <span class="hlt">aerosol</span> collected during the oceanographic cruise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070009991','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070009991"><span id="translatedtitle">Isotopic Measurements in <span class="hlt">CAIs</span> with the Nanosims: Implications to the understanding of the Formation process of Ca, Al-Rich Inclusions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ito, M.; Messenger, S.; Walker, Robert M.</p> <p>2007-01-01</p> <p>Ca, Al-rich Inclusions (<span class="hlt">CAIs</span>) preserve evidence of thermal events that they experienced during their formation in the early solar system. Most <span class="hlt">CAIs</span> from CV and CO chondrites are characterized by large variations in O-isotopic compositions of primary minerals, with spinel, hibonite, and pyroxene being more O-16-rich than melilite and anorthite, with delta 17, O-18 = approx. -40%o (DELTA O-17 = delta O-17 - 0.52 x delta O-18 = approx. - 20%o ). These anomalous compositions cannot be accounted for by standard mass dependent fractionation and diffusive process of those minerals. It requires the presence of an anomalous oxygen reservoir of nucleosynthetic origin or mass independent fractionations before the formation of <span class="hlt">CAIs</span> in the early solar system. The CAMECA NanoSIMS is a new generation ion microprobe that offers high sensitivity isotopic measurements with sub 100 nm spatial resolution. The NanoSIMS has significantly improved abilities in the study of presolar grains in various kind of meteorites and the decay products of extinct nuclides in ancient solar system matter. This instrument promises significant improvements over other conventional ion probes in the precision isotopic characterization of sub-micron scales. We report the results of our first O isotopic measurements of various <span class="hlt">CAI</span> minerals from EK1-6-3 and 7R19-1(a) utilizing the JSC NanoSIMS 50L ion microprobe. We evaluate the measurement conditions, the instrumental mass fractionation factor (IMF) for O isotopic measurement and the accuracy of the isotopic ratio through the analysis of a San Carlos olivine standard and <span class="hlt">CAI</span> sample of 7R19-1(a).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013M%26PS...48.1440B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013M%26PS...48.1440B"><span id="translatedtitle">Mg and Si isotopic fractionation patterns in types B1 and B2 <fc><span class="hlt">CAI</span></fc>s: Implications for formation under different nebular conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bullock, Emma S.; Knight, Kim B.; Richter, Frank M.; Kita, Noriko T.; Ushikubo, Takayuki; MacPherson, Glenn J.; Davis, Andrew M.; Mendybaev, Ruslan A.</p> <p>2013-08-01</p> <p>Magnesium and silicon isotopic profiles across melilite grains in two type B1 and two type B2 calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>) reveal differing but constant enrichments in heavy isotopes everywhere except ≤1000 μm from the <span class="hlt">CAI</span> margins. There is no close correlation in the B1s or the B2s between isotopic composition and åkermanite content of the melilite, a measure of progressive igneous crystallization, yet such a correlation might be expected in a type B2: without a melilite mantle (as in B1s) to seal the interior off and prevent further evaporation, the melt would have maintained communication with the external gas. These observations indicate a model in which B1s and B2s solidified under differing conditions. The B2s solidified under lower hydrogen pressures (PH2 ≤ 10-4 - 10-5 bars) than did B1s (PH2 > 10-4 bars), so surface volatilization was slower in the B2s and internal chemical and isotopic equilibrium was maintained over the interval of melilite crystallization. The outermost zones of the <span class="hlt">CAIs</span> (≤1000 μm from the edge) are not consistently enriched in heavy isotopes relative to the interiors, as might be expected from diffusion-limited surface evaporation of the melt. In all cases, the magnesium in the <span class="hlt">CAI</span> margins is lighter than in the interiors. In one case, silicon in the margin also is lighter, but locally in some <span class="hlt">CAIs</span>, it is isotopically heavier near the surface. If melt evaporation played a role in the formation of these outer zones, a later event in many cases caused isotopic re-equilibration with an external and isotopically near-normal reservoir.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A53K..03L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A53K..03L"><span id="translatedtitle">A 10-year global gridded <span class="hlt">Aerosol</span> Optical Thickness Reanalysis for climate and applied applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lynch, P.; Reid, J. S.; Zhang, J.; Westphal, D. L.; Campbell, J. R.; Curtis, C. A.; Hegg, D.; Hyer, E. J.; Sessions, W.; Shi, Y.; Turk, J.</p> <p>2013-12-01</p> <p>While standalone satellite and model <span class="hlt">aerosol</span> products see wide utilization, there is a significant need of a best-available fused product on a regular grid for numerous climate and applied applications. Remote sensing and modeling technologies have now advanced to a point where <span class="hlt">aerosol</span> data assimilation is an operational reality at numerous centers. It is inevitable that, like meteorological reanalyses, <span class="hlt">aerosol</span> reanalyses will see heavy use in the near future. A first long term, 2003-2012 global 1x1 degree and 6-hourly <span class="hlt">aerosol</span> optical thickness (AOT) reanalysis product has been generated. The goal of this effort is not only for climate applications, but to generate a dataset that can be used by the US Navy to understand operationally hindering <span class="hlt">aerosol</span> events, <span class="hlt">aerosol</span> impacts on numerical weather prediction, and application of electro-optical technologies. The reanalysis utilizes Navy <span class="hlt">Aerosol</span> Analysis and Prediction System (NAAPS) at its core and assimilates quality controlled collection 5 Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) AOD with minor corrections from Multi-angle <span class="hlt">Imaging</span> SpectroRaditometer (MISR). A subset of this product includes Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization (CALIOP) lidar assimilation since its launch in mid-2006. Surface <span class="hlt">aerosol</span> sources, including dust and smoke, in the <span class="hlt">aerosol</span> model have been regionally tuned so that fine and coarse mode AOTs best match those resolve by ground-based <span class="hlt">Aerosol</span> Robotic Network (AERONET). The AOT difference between the model and satellite AOT is then used to adjust other <span class="hlt">aerosol</span> processes, eg., sources, dry deposition, etc. <span class="hlt">Aerosol</span> wet deposition is constrained with satellite-retrieved precipitation. The final AOT reanalysis is shown to exhibit good agreement with AERONET. Here we review the development of the reanalysis and consider issues particular to <span class="hlt">aerosol</span> reanalyses that make them distinct from standard meteorological reanalyses. Considerations are also made for extending such work</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6406E..0EF','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6406E..0EF"><span id="translatedtitle">MAUVE/SWIPE: an <span class="hlt">imaging</span> instrument concept with multi-angular, -spectral, and -polarized capability for remote sensing of <span class="hlt">aerosols</span>, ocean color, clouds, and vegetation from space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frouin, Robert; Deschamps, Pierre-Yves; Rothschild, Richard; Stephan, Edward; Leblanc, Philippe; Duttweiler, Fred; Ghaemi, Tony; Riedi, Jérôme</p> <p>2006-12-01</p> <p>The Monitoring <span class="hlt">Aerosols</span> in the Ultraviolet Experiment (MAUVE) and the Short-Wave Infrared Polarimeter Experiment (SWIPE) instruments have been designed to collect, from a typical sun-synchronous polar orbit at 800 km altitude, global observations of the spectral, polarized, and directional radiance reflected by the earth-atmosphere system for a wide range of applications. Based on the heritage of the POLDER radiometer, the MAUVE/SWIPE instrument concept combines the merits of TOMS for observing in the ultra-violet, MISR for wide field-of-view range, MODIS, for multi-spectral aspects in the visible and near infrared, and the POLDER instrument for polarization. The instruments are camera systems with 2-dimensional detector arrays, allowing a 120-degree field-of-view with adequate ground resolution (i.e., 0.4 or 0.8 km at nadir) from satellite altitude. Multi-angle viewing is achieved by the along-track migration at spacecraft velocity of the 2-dimensional field-of-view. Between the cameras' optical assembly and detector array are two filter wheels, one carrying spectral filters, the other polarizing filters, allowing measurements of the first three Stokes parameters, I. Q, and V, of the incident radiation in 16 spectral bands optimally placed in the interval 350-2200 nm. The spectral range is 350-1050 nm for the MAUVE instrument and 1050-2200 nm for the SWIPE instrument. The radiometric requirements are defined to fully exploit the multi-angular, multi-spectral, and multi-polarized capability of the instruments. These include a wide dynamic range, a signal-to-noise ratio above 500 in all channels at maximum radiance level, i.e., when viewing a surface target of albedo equal to 1, and a noise-equivalent-differential reflectance better than 0.0005 at low signal level for a sun at zenith. To achieve daily global coverage, a pair of MAUVE and SWIPE instruments would be carried by each of two mini-satellites placed on interlaced orbits. The equator crossing time of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRD..117.7207G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRD..117.7207G"><span id="translatedtitle">Retrieval of the <span class="hlt">aerosol</span> direct radiative effect over clouds from spaceborne spectrometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Graaf, M.; Tilstra, L. G.; Wang, P.; Stammes, P.</p> <p>2012-04-01</p> <p>The solar radiative absorption by an <span class="hlt">aerosol</span> layer above clouds is quantified using passive satellite spectrometry from the ultraviolet (UV) to the shortwave infrared (SWIR). UV-absorbing <span class="hlt">aerosols</span> have a strong signature that can be detected using UV reflectance measurements, even when above clouds. Since the <span class="hlt">aerosol</span> extinction optical thickness decreases rapidly with increasing wavelength for biomass burning <span class="hlt">aerosols</span>, the properties of the clouds below the <span class="hlt">aerosol</span> layer can be retrieved in the SWIR, where <span class="hlt">aerosol</span> extinction optical thickness is sufficiently small. Using radiative transfer computations, the contribution of the clouds to the reflected radiation can be modeled for the entire solar spectrum. In this way, cloud and <span class="hlt">aerosol</span> effects can be separated for a scene with <span class="hlt">aerosols</span> above clouds. <span class="hlt">Aerosol</span> microphysical assumptions and retrievals are avoided by modeling only the pure (<span class="hlt">aerosol</span>-free) cloud spectra. An algorithm was developed using the spaceborne spectrometer Scanning <span class="hlt">Imaging</span> Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). The <span class="hlt">aerosol</span> direct radiative effect (DRE) over clouds over the South Atlantic Ocean west of Africa, averaged through August 2006 was found to be 23 ± 8 Wm-2 with a mean variation over the region in this month of 22 Wm-2. The largest <span class="hlt">aerosol</span> DRE over clouds found in that month was 132 ± 8 Wm-2. The algorithm can be applied to any instrument, or a combination of instruments, that measures UV, visible and SWIR reflectances at the top of the atmosphere (TOA) simultaneously.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.usgs.gov/sim/3006/','USGSPUBS'); return false;" href="http://pubs.usgs.gov/sim/3006/"><span id="translatedtitle">Thermal Maturity Patterns (<span class="hlt">CAI</span> and %Ro) in Upper Ordovician and Devonian Rocks of the Appalachian Basin: A Major Revision of USGS Map I-917-E Using New Subsurface Collections</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Repetski, John E.; Ryder, Robert T.; Weary, David J.; Harris, Anita G.; Trippi, Michael H.</p> <p>2008-01-01</p> <p>The conodont color alteration index (<span class="hlt">CAI</span>) introduced by Epstein and others (1977) and Harris and others (1978) is an important criterion for estimating the thermal maturity of Ordovician to Mississippian rocks in the Appalachian basin. Consequently, the <span class="hlt">CAI</span> isograd maps of Harris and others (1978) are commonly used by geologists to characterize the thermal and burial history of the Appalachian basin and to better understand the origin and distribution of oil and gas resources in the basin. The main objectives of our report are to present new <span class="hlt">CAI</span> isograd maps for Ordovician and Devonian rocks in the Appalachian basin and to interpret the geologic and petroleum resource implications of these maps. The <span class="hlt">CAI</span> isograd maps presented herein complement, and in some areas replace, the <span class="hlt">CAI</span>-based isograd maps of Harris and others (1978) for the Appalachian basin. The <span class="hlt">CAI</span> data presented in this report were derived almost entirely from subsurface samples, whereas the <span class="hlt">CAI</span> data used by Harris and others (1978) were derived almost entirely from outcrop samples. Because of the different sampling methods, there is little geographic overlap of the two data sets. The new data set is mostly from the Allegheny Plateau structural province and most of the data set of Harris and others (1978) is from the Valley and Ridge structural province, east of the Allegheny structural front.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20160000375&hterms=property&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dproperty','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20160000375&hterms=property&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dproperty"><span id="translatedtitle">Volcanic <span class="hlt">Aerosol</span> Radiative Properties</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lacis, Andrew</p> <p>2015-01-01</p> <p>Large sporadic volcanic eruptions inject large amounts of sulfur bearing gases into the stratosphere which then get photochemically converted to sulfuric acid <span class="hlt">aerosol</span> droplets that exert a radiative cooling effect on the global climate system lasting for several years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatGe...8..174P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatGe...8..174P"><span id="translatedtitle">Palaeoclimate: <span class="hlt">Aerosols</span> and rainfall</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Partin, Jud</p> <p>2015-03-01</p> <p>Instrumental records have hinted that <span class="hlt">aerosol</span> emissions may be shifting rainfall over Central America southwards. A 450-year-long precipitation reconstruction indicates that this shift began shortly after the Industrial Revolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/788898','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/788898"><span id="translatedtitle">Emergency Protection from <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cristy, G.A.</p> <p>2001-11-13</p> <p>Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) <span class="hlt">aerosols</span>. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the <span class="hlt">aerosol</span> cloud. Protection factors of 800 and above were achieved.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5731374','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5731374"><span id="translatedtitle">Emergency protection from <span class="hlt">aerosols</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cristy, G.A.; Chester, C.V.</p> <p>1981-07-01</p> <p>Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) <span class="hlt">aerosols</span>. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the <span class="hlt">aerosol</span> cloud. Protection factors of 800 and above were achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/867343','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/867343"><span id="translatedtitle">Monodisperse <span class="hlt">aerosol</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ortiz, Lawrence W.; Soderholm, Sidney C.</p> <p>1990-01-01</p> <p>An <span class="hlt">aerosol</span> generator is described which is capable of producing a monodisperse <span class="hlt">aerosol</span> within narrow limits utilizing an aqueous solution capable of providing a high population of seed nuclei and an organic solution having a low vapor pressure. The two solutions are cold nebulized, mixed, vaporized, and cooled. During cooling, particles of the organic vapor condense onto the excess seed nuclei, and grow to a uniform particle size.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150000796','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150000796"><span id="translatedtitle">MISR <span class="hlt">Aerosol</span> Typing</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kahn, Ralph A.</p> <p>2014-01-01</p> <p>AeroCom is an open international initiative of scientists interested in the advancement of the understanding of global <span class="hlt">aerosol</span> properties and <span class="hlt">aerosol</span> impacts on climate. A central goal is to more strongly tie and constrain modeling efforts to observational data. A major element for exchanges between data and modeling groups are annual meetings. The meeting was held September 20 through October 2, 1014 and the organizers would like to post the presentations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1028128','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1028128"><span id="translatedtitle">RACORO <span class="hlt">aerosol</span> data processing</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Elisabeth Andrews</p> <p>2011-10-31</p> <p>The RACORO <span class="hlt">aerosol</span> data (cloud condensation nuclei (CCN), condensation nuclei (CN) and <span class="hlt">aerosol</span> size distributions) need further processing to be useful for model evaluation (e.g., GCM droplet nucleation parameterizations) and other investigations. These tasks include: (1) Identification and flagging of 'splash' contaminated Twin Otter <span class="hlt">aerosol</span> data. (2) Calculation of actual supersaturation (SS) values in the two CCN columns flown on the Twin Otter. (3) Interpolation of CCN spectra from SGP and Twin Otter to 0.2% SS. (4) Process data for spatial variability studies. (5) Provide calculated light scattering from measured <span class="hlt">aerosol</span> size distributions. Below we first briefly describe the measurements and then describe the results of several data processing tasks that which have been completed, paving the way for the scientific analyses for which the campaign was designed. The end result of this research will be several <span class="hlt">aerosol</span> data sets which can be used to achieve some of the goals of the RACORO mission including the enhanced understanding of cloud-<span class="hlt">aerosol</span> interactions and improved cloud simulations in climate models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JGRD..11010S11C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JGRD..11010S11C"><span id="translatedtitle">Variability of <span class="hlt">aerosol</span> and spectral lidar and backscatter and extinction ratios of key <span class="hlt">aerosol</span> types derived from selected <span class="hlt">Aerosol</span> Robotic Network locations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cattrall, Christopher; Reagan, John; Thome, Kurt; Dubovik, Oleg</p> <p>2005-05-01</p> <p>The lidar (extinction-to-backscatter) ratios at 0.55 and 1.02 μm and the spectral lidar, extinction, and backscatter ratios of climatically relevant <span class="hlt">aerosol</span> species are computed on the basis of selected retrievals of <span class="hlt">aerosol</span> properties from 26 <span class="hlt">Aerosol</span> Robotic Network (AERONET) sites across the globe. The values, obtained indirectly from sky radiance and solar transmittance measurements, agree very well with values from direct observations. Low mean values of the lidar ratio, Sa, at 0.55 μm for maritime (27 sr) <span class="hlt">aerosols</span> and desert dust (42 sr) are clearly distinguishable from biomass burning (60 sr) and urban/industrial pollution (71 sr). The effects of nonsphericity of mineral dust are shown, demonstrating that particle shape must be taken into account in any spaceborne lidar inversion scheme. A new <span class="hlt">aerosol</span> model representing pollution over Southeast Asia is introduced since lidar (58 sr), color lidar, and extinction ratios in this region are distinct from those over other urban/industrial centers, owing to a greater number of large particles relative to fine particles. This discrimination promises improved estimates of regional climate forcing by <span class="hlt">aerosols</span> containing black carbon and is expected to be of utility to climate modeling and remote sensing communities. The observed variability of the lidar parameters, combined with current validated <span class="hlt">aerosol</span> data products from Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), will afford improved accuracy in the inversion of spaceborne lidar data over both land and ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21399788','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21399788"><span id="translatedtitle">VUV state-selected photoionization of thermally-desorbed biomolecules by coupling an <span class="hlt">aerosol</span> source to an <span class="hlt">imaging</span> photoelectron/photoion coincidence spectrometer: case of the amino acids tryptophan and phenylalanine.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gaie-Levrel, François; Garcia, Gustavo A; Schwell, Martin; Nahon, Laurent</p> <p>2011-04-21</p> <p>Gas phase studies of biological molecules provide structural and dynamical information on isolated systems. The lack of inter- or intra-molecular interactions facilitates the interpretation of the experimental results through theoretical calculations, and constitutes an informative complement to the condensed phase. However advances in the field are partially hindered by the difficulty of vaporising these systems, most of which are thermally unstable. In this work we present a newly developed <span class="hlt">aerosol</span> mass thermodesorption setup, which has been coupled to a Velocity Map <span class="hlt">Imaging</span> (VMI) analyzer operated in coincidence with a Wiley-McLaren Time of Flight spectrometer, using synchrotron radiation as a single photon ionization source. Although it has been previously demonstrated that thermolabile molecules such as amino acids can be produced intact by the <span class="hlt">aerosol</span> vaporisation technique, we show how its non-trivial coupling to a VMI analyzer plus the use of electron/ion coincidences greatly improves the concept in terms of the amount of spectroscopic and dynamic information that can be extracted. In this manner, we report on the valence shell ionization of two amino acids, tryptophan and phenylalanine, for which threshold photoelectron spectra have been recorded within the first 3 eV above the first ionization energy using synchrotron radiation emitted from the DESIRS beamline located at SOLEIL in France. Their adiabatic ionization energies (IEs) have been measured at 7.40 ± 0.05 and 8.65 ± 0.02 eV, respectively, and their spectra analyzed using existing theoretical data from the literature. The IE values agree well with previously published ones, but are given here with a considerably reduced uncertainty by up to a factor of 5. The photostability of both amino acids is also described in detail, through the measurement of the state-selected fragmentation pathways via the use of threshold electron/ion coincidences (TPEPICO), with appearance energies for the different</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRD..11612205S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRD..11612205S"><span id="translatedtitle">Direct and semidirect <span class="hlt">aerosol</span> effects of southern African biomass burning <span class="hlt">aerosol</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sakaeda, Naoko; Wood, Robert; Rasch, Philip J.</p> <p>2011-06-01</p> <p>Direct and semidirect radiative effects of biomass burning <span class="hlt">aerosols</span> from southern African fires during July-October are investigated using 20 year runs of the Community Atmospheric Model (CAM) coupled to a slab ocean model. <span class="hlt">Aerosol</span> optical depth is constrained using observations in clear skies from Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) and for <span class="hlt">aerosol</span> layers above clouds from Cloud <span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observation (CALIPSO). Over the ocean, where the <span class="hlt">aerosol</span> layers are primarily located above cloud, negative top of atmosphere (TOA) semidirect radiative effects associated with increased low cloud cover dominate over a weaker positive all-sky direct radiative effect (DRE). In contrast, over the land where the <span class="hlt">aerosols</span> are often below or within cloud layers, reductions in cloud liquid water path (LWP) lead to a positive semidirect radiative effect that dominates over a near-zero DRE. Over the ocean, the cloud response can be understood as a response to increased lower tropospheric stability (LTS) which is caused both by radiative heating in overlying layers and surface cooling in response to direct <span class="hlt">aerosol</span> forcing. The marine cloud changes are robust to changes in the cloud parameterization (removal of the hard-wired dependence of clouds on LTS), suggesting that they are physically realistic. Over land, decreased LWP is consistent with weaker convection driven by increased static stability. Over the entire region the overall TOA radiative effect from the biomass burning <span class="hlt">aerosols</span> is almost zero due to opposing effects over the land and ocean. However, the surface forcing is strongly negative, which leads to a reduction in precipitation and also a reduction in sensible heat flux. The former is primarily realized through reductions in convective precipitation on both the southern and northern flanks of the convective precipitation region spanning the equatorial rain forest and the Intertropical Convergence Zone (ITCZ) in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/841588','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/841588"><span id="translatedtitle">Representing Cloud Processing of <span class="hlt">Aerosol</span> in Numerical Models</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mechem, D.B.; Kogan, Y.L.</p> <p>2005-03-18</p> <p>The satellite imagery in Figure 1 provides dramatic examples of how <span class="hlt">aerosol</span> influences the cloud field. <span class="hlt">Aerosol</span> from ship exhaust can serve as nucleation centers in otherwise cloud-free regions, forming ship tracks (top <span class="hlt">image</span>), or can enhance the reflectance/albedo in already cloudy regions. This <span class="hlt">image</span> is a demonstration of the first indirect effect, in which changes in <span class="hlt">aerosol</span> modulate cloud droplet radius and concentration, which influences albedo. It is thought that, through the effects it has on precipitation (drizzle), <span class="hlt">aerosol</span> can also affect the structure and persistence of planetary boundary layer (PBL) clouds. Regions of cellular convection, or open pockets of cloudiness (bottom <span class="hlt">image</span>) are thought to be remnants of strongly drizzling PBL clouds. Pockets of Open Cloudiness (POCs) (Stevens et al. 2005) or Albrecht's ''rifts'' are low cloud fraction regions characterized by anomalously low <span class="hlt">aerosol</span> concentrations, implying they result from precipitation. These features may in fact be a demonstration of the second indirect effect. To accurately represent these clouds in numerical models, we have to treat the coupled cloud-<span class="hlt">aerosol</span> system. We present the following series of mesoscale and large eddy simulation (LES) experiments to evaluate the important aspects of treating the coupled cloud-<span class="hlt">aerosol</span> problem. 1. Drizzling and nondrizzling simulations demonstrate the effect of drizzle on a mesoscale forecast off the California coast. 2. LES experiments with explicit (bin) microphysics gauge the relative importance of the shape of the <span class="hlt">aerosol</span> spectrum on the 3D dynamics and cloud structure. 3. Idealized mesoscale model simulations evaluate the relative roles of various processes, sources, and sinks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1277722','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1277722"><span id="translatedtitle">Recovery of Pasteurella hemolytica from <span class="hlt">aerosols</span> at differing temperature and humidity.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jericho, K W; Langford, E V; Pantekoek, J</p> <p>1977-01-01</p> <p>A Pasteurella hemolytica suspension with fetal calf serum was <span class="hlt">aerosolized</span> in a standard system with ambient temperature of 30 or 2 degrees C and relative humidity conditions of 90 or 60%. The number of organisms sprayed in five minutes and the number recovered from one third of the <span class="hlt">aerosol</span> during these five minutes was determined. Recoveries were influenced by temperature difference between <span class="hlt">aerosol</span> and collecting fluid. Recoveries ranged between 0.059--0.94%. <span class="hlt">Images</span> Fig. 1. PMID:861840</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20120003884&hterms=disentangling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddisentangling','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20120003884&hterms=disentangling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddisentangling"><span id="translatedtitle">Observational Evidence of <span class="hlt">Aerosol</span> Enhancement of Lightning Activity and Convective Invigoration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Yuan, Tianle; Remer, Lorraine A.; Pickering, Kenneth E.; Yu, Hongbin</p> <p>2011-01-01</p> <p>Lightning activity over the West Pacific Ocean east of the Philippines is usually much less frequent than over the nearby maritime continents. However, in 2005 the Lightning <span class="hlt">Imaging</span> Sensor (LIS) aboard the TRMM satellite observed anomalously high lightning activity in that area. In the same year the Moderate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) measured anomalously high <span class="hlt">aerosol</span> loading. The high <span class="hlt">aerosol</span> loading was traced to volcanic activity, and not to any factor linked to meteorology, disentangling the usual convolution between <span class="hlt">aerosols</span> and meteorology. We show that in general lightning activity is tightly correlated with <span class="hlt">aerosol</span> loadings at both inter-annual and biweekly time scales. We estimate that a approximately 60% increase in <span class="hlt">aerosol</span> loading leads to more than 150% increase in lightning flashes. <span class="hlt">Aerosols</span> increase lightning activity through modification of cloud microphysics. Cloud ice particle sizes are reduced and cloud glaciation is delayed to colder temperature when <span class="hlt">aerosol</span> loading is increased. TRMM precipitation radar measurements indicate that anomalously high <span class="hlt">aerosol</span> loading is associated with enhanced cloud mixed phase activity and invigorated convection over the maritime ocean. These observed associations between <span class="hlt">aerosols</span>, cloud microphysics, morphology and lightning activity are not related to meteorological variables or ENSO events. The results have important implications for understanding the variability of lightning and resulting <span class="hlt">aerosol</span>-chemistry interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011SPIE.8018E..02B&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011SPIE.8018E..02B&link_type=ABSTRACT"><span id="translatedtitle">Biological <span class="hlt">aerosol</span> background characterization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blatny, Janet; Fountain, Augustus W., III</p> <p>2011-05-01</p> <p>To provide useful information during military operations, or as part of other security situations, a biological <span class="hlt">aerosol</span> detector has to respond within seconds or minutes to an attack by virulent biological agents, and with low false alarms. Within this time frame, measuring virulence of a known microorganism is extremely difficult, especially if the microorganism is of unknown antigenic or nucleic acid properties. Measuring "live" characteristics of an organism directly is not generally an option, yet only viable organisms are potentially infectious. Fluorescence based instruments have been designed to optically determine if <span class="hlt">aerosol</span> particles have viability characteristics. Still, such commercially available biological <span class="hlt">aerosol</span> detection equipment needs to be improved for their use in military and civil applications. Air has an endogenous population of microorganisms that may interfere with alarm software technologies. To design robust algorithms, a comprehensive knowledge of the airborne biological background content is essential. For this reason, there is a need to study ambient live bacterial populations in as many locations as possible. Doing so will permit collection of data to define diverse biological characteristics that in turn can be used to fine tune alarm algorithms. To avoid false alarms, improving software technologies for biological detectors is a crucial feature requiring considerations of various parameters that can be applied to suppress alarm triggers. This NATO Task Group will aim for developing reference methods for monitoring biological <span class="hlt">aerosol</span> characteristics to improve alarm algorithms for biological detection. Additionally, they will focus on developing reference standard methodology for monitoring biological <span class="hlt">aerosol</span> characteristics to reduce false alarm rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eosweb.larc.nasa.gov/project/misr/uae/uae_aerosol_versioning','SCIGOV-ASDC'); return false;" href="https://eosweb.larc.nasa.gov/project/misr/uae/uae_aerosol_versioning"><span id="translatedtitle">MISR UAE2 <span class="hlt">Aerosol</span> Versioning</span></a></p> <p><a target="_blank" href="http://eosweb.larc.nasa.gov/">Atmospheric Science Data Center </a></p> <p></p> <p>2013-03-21</p> <p>... the MISR <span class="hlt">aerosol</span> microphysical properties are "Beta." Uncertainty envelopes for the <span class="hlt">aerosol</span> optical depths are given in  Kahn et ... particle microphysical property validation is in progress, uncertainty envelopes on particle size distribution, shape, and ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatGe...9....7Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatGe...9....7Z"><span id="translatedtitle">Atmospheric Chemistry: Nature's plasticized <span class="hlt">aerosols</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ziemann, Paul J.</p> <p>2016-01-01</p> <p>The structure of atmospheric <span class="hlt">aerosol</span> particles affects their reactivity and growth rates. Measurements of <span class="hlt">aerosol</span> properties over the Amazon rainforest indicate that organic particles above tropical rainforests are simple liquid drops.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014E%26ES...18a2085L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014E%26ES...18a2085L"><span id="translatedtitle">Preliminary results of the <span class="hlt">aerosol</span> optical depth retrieval in Johor, Malaysia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, H. Q.; Kanniah, K. D.; Lau, A. M. S.</p> <p>2014-02-01</p> <p>Monitoring of atmospheric <span class="hlt">aerosols</span> over the urban area is important as tremendous amounts of pollutants are released by industrial activities and heavy traffic flow. Air quality monitoring by satellite observation provides better spatial coverage, however, detailed <span class="hlt">aerosol</span> properties retrieval remains a challenge. This is due to the limitation of <span class="hlt">aerosol</span> retrieval algorithm on high reflectance (bright surface) areas. The aim of this study is to retrieve <span class="hlt">aerosol</span> optical depth over urban areas of Iskandar Malaysia; the main southern development zone in Johor state, using Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) 500 m resolution data. One of the important steps is the <span class="hlt">aerosol</span> optical depth retrieval is to characterise different types of <span class="hlt">aerosols</span> in the study area. This information will be used to construct a Look Up Table containing the simulated <span class="hlt">aerosol</span> reflectance and corresponding <span class="hlt">aerosol</span> optical depth. Thus, in this study we have characterised different <span class="hlt">aerosol</span> types in the study area using <span class="hlt">Aerosol</span> Robotic Network (AERONET) data. These data were processed using cluster analysis and the preliminary results show that the area is consisting of coastal urban (65%), polluted urban (27.5%), dust particles (6%) and heavy pollution (1.5%) <span class="hlt">aerosols</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1058369','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1058369"><span id="translatedtitle">Sampling Submicron T1 Bacteriophage <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Harstad, J. Bruce</p> <p>1965-01-01</p> <p>Liquid impingers, filter papers, and fritted bubblers were partial viable collectors of radioactive submicron T1 bacteriophage <span class="hlt">aerosols</span> at 30, 55, and 85% relative humidity. Sampler differences for viable collection were due to incomplete physical collection (slippage) and killing of phage by the samplers. Dynamic <span class="hlt">aerosols</span> of a mass median diameter of 0.2 μ were produced with a Dautrebande generator from concentrated aqueous purified phage suspensions containing extracellular soluble radioactive phosphate as a physical tracer. There was considerable destruction of phage by the Dautrebande generator; phage titers of the Dautrebande suspension decreased exponentially, but there was a progressive (linear) increase in tracer titers. Liquid impingers recovered the most viable phage but allowed considerable (30 to 48%) slippage, which varies inversely with the <span class="hlt">aerosol</span> relative humidity. Filter papers were virtually complete physical collectors of submicron particles but were the most destructive. Fritted bubbler slippage was more than 80%. With all samplers, phage kill was highest at 85% relative humidity and lowest at 55% relative humidity. An electrostatic precipitator was used to collect <span class="hlt">aerosol</span> samples for particle sizing with an electron microscope. The particle size was slightly larger at 85% relative humidity than at 30 or 55% relative humidity. <span class="hlt">Images</span> Fig. 1 Fig. 4 PMID:5866038</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160002232','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160002232"><span id="translatedtitle">New Petrology, Mineral Chemistry and Stable MG Isotope Compositions of an Allende <span class="hlt">CAI</span>: EK-459-7-2</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jeffcoat, C. R.; Kerekgyarto, A. G.; Lapen, T. J.; Righter, M.; Simon, J. I.; Ross, D. K.</p> <p>2016-01-01</p> <p>Calcium-aluminum-rich inclusions (<span class="hlt">CAIs</span>) are the key to understanding physical and chemical conditions in the nascent solar nebula. These inclusions have the oldest radiometric ages of solar system materials and are composed of phases that are predicted to condense early from a gas of solar composition. Thus, their chemistry and textures record conditions and processes in the earliest stages of development of the solar nebula. Type B inclusions are typically larger and more coarse grained than other types with substantial evidence that many of them were at least partially molten. Type B inclusions are further subdivided into Type B1 (possess thick melilite mantle) and Type B2 (lack melilite mantle). Despite being extensively studied, the origin of the melilite mantles of Type B1 inclusions remains uncertain. We present petrologic and chemical data for a Type B inclusion, EK-459-7-2, that bears features found in both Type B1 and B2 inclusions and likely represents an intermediate between the two types. Detailed studies of more of these intermediate objects may help to constrain models for Type B1 rim formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014SPIE.9232E..0NS&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014SPIE.9232E..0NS&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Aerosol</span> characterization with lidar methods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sugimoto, Nobuo; Nishizawa, Tomoaki; Shimizu, Atsushi; Matsui, Ichiro</p> <p>2014-08-01</p> <p><span class="hlt">Aerosol</span> component analysis methods for characterizing <span class="hlt">aerosols</span> were developed for various types of lidars including polarization-sensitive Mie scattering lidars, multi-wavelength Raman scattering lidars, and multi-wavelength highspectral- resolution lidars. From the multi-parameter lidar data, the extinction coefficients for four <span class="hlt">aerosol</span> components can be derived. The microphysical parameters such as single scattering albedo and effective radius can be also estimated from the derived <span class="hlt">aerosol</span> component distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812228M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812228M"><span id="translatedtitle">Optical properties of <span class="hlt">aerosol</span> contaminated cloud derived from MODIS instrument</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mei, Linlu; Rozanov, Vladimir; Lelli, Luca; Vountas, Marco; Burrows, John P.</p> <p>2016-04-01</p> <p>The presence of absorbing <span class="hlt">aerosols</span> above/within cloud can reduce the amount of up-welling radiation in visible (VIS) and short-wave infrared and darken the spectral reflectance when compared with a spectrum of a clean cloud observed by satellite instruments (Jethva et al., 2013). Cloud properties retrieval for <span class="hlt">aerosol</span> contaminated cases is a great challenge. Even small additional injection of <span class="hlt">aerosol</span> particles into clouds in the cleanest regions of Earth's atmosphere will cause significant effect on those clouds and on climate forcing (Koren et al., 2014; Rosenfeld et al., 2014) because the micro-physical cloud process are non-linear with respect to the <span class="hlt">aerosol</span> loading. The current cloud products like Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) ignoring the <span class="hlt">aerosol</span> effect for the retrieval, which may cause significant error in the satellite-derived cloud properties. In this paper, a new cloud properties retrieval method, considering <span class="hlt">aerosol</span> effect, based on the weighting-function (WF) method, is presented. The retrieval results shows that the WF retrieved cloud properties (e.g COT) agrees quite well with MODIS COT product for relative clear atmosphere (AOT ≤ 0.4) while there is a large difference for large <span class="hlt">aerosol</span> loading. The MODIS COT product is underestimated for at least 2 - 3 times for AOT>0.4, and this underestimation increases with the increase of AOT.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7416R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7416R"><span id="translatedtitle">Merging the SAGE II and OSIRIS Stratospheric <span class="hlt">Aerosol</span> Records</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rieger, Landon; Bourassa, Adam; Degenstein, Doug</p> <p>2016-04-01</p> <p>The Optical Spectrograph and InfraRed <span class="hlt">Imaging</span> System (OSIRIS) instrument on the Odin satellite, launched in 2001 and currently operational, measures limb-scattered sunlight from which profiles of stratospheric <span class="hlt">aerosol</span> extinction at 750nm are retrieved. The Stratospheric <span class="hlt">Aerosol</span> and Gas (SAGE) II instrument was operational from 1985 to 2005, and provided <span class="hlt">aerosol</span> extinction at several visible and near infrared wavelengths. This work compares the SAGE II and OSIRIS <span class="hlt">aerosol</span> extinction measurements during the four years of instrument overlap by interpolating the SAGE II data to 750nm using the 525 and 1020nm channels. Agreement is generally favourable in the tropics and mid-latitudes with differences less than 10% for the majority of the <span class="hlt">aerosol</span> layer. However, near the UTLS and outside of the tropics agreement is poorer and reasons for this are investigated. Comparisons between the OSIRIS and SAGE II <span class="hlt">aerosol</span> extinction measurements at 750nm are used to develop a merged <span class="hlt">aerosol</span> climatology as a function of time, latitude and altitude at the native SAGE II wavelength of 525nm. Error due to assumptions in the OSIRIS retrieval and wavelength conversion are explored through simulation studies over a range of particle size distributions and is found to be approximately 20% for the majority of low-to-moderate volcanic loading conditions and OSIRIS geometries. Other sources of error such as cloud contamination in the UTLS are also explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=GL-2002-002182&hterms=pollution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dpollution','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=GL-2002-002182&hterms=pollution&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dpollution"><span id="translatedtitle"><span class="hlt">Aerosol</span> pollution over Northern India and Bangladesh</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p>The skies over Northern India are filled with a thick soup of <span class="hlt">aerosol</span> particles all along the southern edge of the Himalayan Mountains, and streaming southward over Bangladesh and the Bay of Bengal. Notice that the air over the Tibetan Plateau to the north of the Himalayas is very clear, whereas the view of the land surface south of the mountains is obstructed by the brownish haze. Most of this air pollution comes from human activities. The <span class="hlt">aerosol</span> over this region is notoriously rich in sulfates, nitrates, organic and black carbon, and fly ash. These particles not only represent a health hazard to those people living in the region, but scientists have also recently found that they can have a significant impact on the region's hydrological cycle and climate (click to read the relevant NASA press release). This true-color <span class="hlt">image</span> was acquired on December 4, 2001, by the Moderate-resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. It is interesting to compare the <span class="hlt">image</span> above with this earlier MODIS <span class="hlt">image</span> over the region, acquired on October 23, 2001. Notice the difference in the clarity of the air over the region in the earlier <span class="hlt">image</span>. Under the thick plume of <span class="hlt">aerosol</span>, the Brahmaputra (upper right) and Ganges Rivers are still visible. The many mouths of the Ganges have turned the northern waters of the Bay of Bengal a murky brown as they empty their sediment-laden waters into the bay. Toward the upper lefthand corner of the <span class="hlt">image</span>, there appears to be a fresh swath of snow on the ground just south of the Himalayas.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED111337.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED111337.pdf"><span id="translatedtitle">CHARGE <span class="hlt">Image</span> Generator: Theory of Operation and Author Language Support. Technical Report 75-3.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Gunwaldsen, Roger L.</p> <p></p> <p>The <span class="hlt">image</span> generator function and author language software support for the CHARGE (Color Halftone Area Graphics Environment) Interactive Graphics System are described. Designed initially for use in computer-assisted instruction (<span class="hlt">CAI</span>) systems, the CHARGE Interactive Graphics System can provide graphic displays for various applications including…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.A53C0366L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.A53C0366L"><span id="translatedtitle"><span class="hlt">Aerosol</span> Quality Monitor (AQUAM)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liang, X.; Ignatov, A.</p> <p>2011-12-01</p> <p>The Advanced Clear-Sky Processor for Oceans (ACSPO) developed at NESDIS generates three products from AVHRR, operationally: clear sky radiances in all bands, and sea surface temperature (SST) derived from clear-sky brightness temperatures (BT) in Ch3B (centered at 3.7 μm), Ch4 (11 μm) and Ch5 (12 μm), and <span class="hlt">aerosol</span> optical depths (AOD) derived from clear-sky reflectances in Ch1 (0.63), Ch2 (0.83) and Ch3A (1.61 μm). An integral part of ACSPO is the fast Community Radiative Transfer Model (CRTM), which calculates first-guess clear-sky BTs using global NCEP forecast atmospheric and Reynolds SST fields. Simulated BTs are employed in ACSPO for improved cloud screening, physical (RTM-based) SST inversions, and to monitor and validate satellite BTs. The model minus observation biases are monitored online in near-real time using the Monitoring IR Clear-sky radiances over Oceans for SST (MICROS; http://www.star.nesdis.noaa.gov/sod/sst/micros/). A persistent positive M-O bias is observed in MICROS, partly attributed to missing <span class="hlt">aerosol</span> in CRTM input, causing "M" to be warmer than "O". It is thus necessary to include <span class="hlt">aerosols</span> in CRTM and quantify their effects on AVHRR BTs and SSTs. However, sensitivity of thermal bands to <span class="hlt">aerosol</span> is only minimal, and use of solar reflectance bands is preferable to evaluate the accuracy of CRTM modeling, with global <span class="hlt">aerosol</span> fields as input (from e.g. Goddard Chemistry <span class="hlt">Aerosol</span> Radiation and Transport, GOCART, or Navy <span class="hlt">Aerosol</span> Analysis and Prediction System, NAAPS). Once available, the corresponding M-O biases in solar reflectance bands will be added to MICROS. Also, adding CRTM simulated reflectances in ACSPO would greatly improve cloud detection, help validate CRTM in the solar reflectance bands, and assist <span class="hlt">aerosol</span> retrievals. Running CRTM with global <span class="hlt">aerosol</span> as input is very challenging, computationally. While CRTM is being optimized to handle such global scattering computations, a near-real time web-based <span class="hlt">Aerosol</span> Quality Monitor (AQUAM</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1230771','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1230771"><span id="translatedtitle">Cantera <span class="hlt">Aerosol</span> Dynamics Simulator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Moffat, Harry</p> <p>2004-09-01</p> <p>The Cantera <span class="hlt">Aerosol</span> Dynamics Simulator (CADS) package is a general library for <span class="hlt">aerosol</span> modeling to address <span class="hlt">aerosol</span> general dynamics, including formation from gas phase reactions, surface chemistry (growth and oxidation), bulk particle chemistry, transport by Brownian diffusion, thermophoresis, and diffusiophoresis with linkage to DSMC studies, and thermal radiative transport. The library is based upon Cantera, a C++ Cal Tech code that handles gas phase species transport, reaction, and thermodynamics. The method uses a discontinuous galerkin formulation for the condensation and coagulation operator that conserves particles, elements, and enthalpy up to round-off error. Both O-D and 1-D time dependent applications have been developed with the library. Multiple species in the solid phase are handled as well. The O-D application, called Tdcads (Time Dependent CADS) is distributed with the library. Tdcads can address both constant volume and constant pressure adiabatic homogeneous problems. An extensive set of sample problems for Tdcads is also provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/12492171','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/12492171"><span id="translatedtitle">Indian <span class="hlt">aerosols</span>: present status.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mitra, A P; Sharma, C</p> <p>2002-12-01</p> <p>This article presents the status of <span class="hlt">aerosols</span> in India based on the research activities undertaken during last few decades in this region. Programs, like International Geophysical Year (IGY), Monsoon Experiment (MONEX), Indian Middle Atmospheric Program (IMAP) and recently conducted Indian Ocean Experiment (INDOEX), have thrown new lights on the role of <span class="hlt">aerosols</span> in global change. INDOEX has proved that the effects of <span class="hlt">aerosols</span> are no longer confined to the local levels but extend at regional as well as global scales due to occurrence of long range transportation of <span class="hlt">aerosols</span> from source regions along with wind trajectories. The loading of <span class="hlt">aerosols</span> in the atmosphere is on rising due to energy intensive activities for developmental processes and other anthropogenic activities. One of the significant observation of INDOEX is the presence of high concentrations of carbonaceous <span class="hlt">aerosols</span> in the near persistent winter time haze layer over tropical Indian Ocean which have probably been emitted from the burning of fossil-fuels and biofuels in the source region. These have significant bearing on the radiative forcing in the region and, therefore, have potential to alter monsoon and hydrological cycles. In general, the SPM concentrations have been found to be on higher sides in ambient atmosphere in many Indian cities but the NOx concentrations have been found to be on lower side. Even in the haze layer over Indian Ocean and surrounding areas, the NOx concentrations have been reported to be low which is not conducive of O3 formation in the haze/smog layer. The acid rain problem does not seem to exist at the moment in India because of the presence of neutralizing soil dust in the atmosphere. But the high particulate concentrations in most of the cities' atmosphere in India are of concern as it can cause deteriorated health conditions. PMID:12492171</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12492171','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12492171"><span id="translatedtitle">Indian <span class="hlt">aerosols</span>: present status.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mitra, A P; Sharma, C</p> <p>2002-12-01</p> <p>This article presents the status of <span class="hlt">aerosols</span> in India based on the research activities undertaken during last few decades in this region. Programs, like International Geophysical Year (IGY), Monsoon Experiment (MONEX), Indian Middle Atmospheric Program (IMAP) and recently conducted Indian Ocean Experiment (INDOEX), have thrown new lights on the role of <span class="hlt">aerosols</span> in global change. INDOEX has proved that the effects of <span class="hlt">aerosols</span> are no longer confined to the local levels but extend at regional as well as global scales due to occurrence of long range transportation of <span class="hlt">aerosols</span> from source regions along with wind trajectories. The loading of <span class="hlt">aerosols</span> in the atmosphere is on rising due to energy intensive activities for developmental processes and other anthropogenic activities. One of the significant observation of INDOEX is the presence of high concentrations of carbonaceous <span class="hlt">aerosols</span> in the near persistent winter time haze layer over tropical Indian Ocean which have probably been emitted from the burning of fossil-fuels and biofuels in the source region. These have significant bearing on the radiative forcing in the region and, therefore, have potential to alter monsoon and hydrological cycles. In general, the SPM concentrations have been found to be on higher sides in ambient atmosphere in many Indian cities but the NOx concentrations have been found to be on lower side. Even in the haze layer over Indian Ocean and surrounding areas, the NOx concentrations have been reported to be low which is not conducive of O3 formation in the haze/smog layer. The acid rain problem does not seem to exist at the moment in India because of the presence of neutralizing soil dust in the atmosphere. But the high particulate concentrations in most of the cities' atmosphere in India are of concern as it can cause deteriorated health conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6560T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6560T"><span id="translatedtitle">Easy Volcanic <span class="hlt">Aerosol</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toohey, Matthew; Stevens, Bjorn; Schmidt, Hauke; Timmreck, Claudia</p> <p>2016-04-01</p> <p>Radiative forcing by stratospheric sulfate <span class="hlt">aerosol</span> of volcanic origin is one of the strongest drivers of natural climate variability. Transient model simulations attempting to match observed climate variability, such as the CMIP historical simulations, rely on volcanic forcing reconstructions based on observations of a small sample of recent eruptions and coarse proxy data for eruptions before the satellite era. Volcanic forcing data sets used in CMIP5 were provided either in terms of optical properties, or in terms of sulfate <span class="hlt">aerosol</span> mass, leading to significant inter-model spread in the actual volcanic radiative forcing produced by models and in their resulting climate responses. It remains therefore unclear to what degree inter-model spread in response to volcanic forcing represents model differences or variations in the forcing. In order to isolate model differences, Easy Volcanic <span class="hlt">Aerosol</span> (EVA) provides an analytic representation of volcanic stratospheric <span class="hlt">aerosol</span> forcing, based on available observations and <span class="hlt">aerosol</span> model results, prescribing the <span class="hlt">aerosol</span>'s radiative properties and primary modes of spatial and temporal variability. In contrast to regriddings of observational data, EVA allows for the production of physically consistent forcing for historic and hypothetical eruptions of varying magnitude, source latitude, and season. Within CMIP6, EVA will be used to reconstruct volcanic forcing over the past 2000 years for use in the Paleo-Modeling Intercomparison Project (PMIP), and will provide forcing sets for VolMIP experiments aiming to quantify model uncertainty in the response to volcanic forcing. Here, the functional form of EVA will be introduced, along with illustrative examples including the EVA-based reconstruction of volcanic forcing over the historical period, and that of the 1815 Tambora eruption.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.4472K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.4472K"><span id="translatedtitle">simplified <span class="hlt">aerosol</span> representations in global modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kinne, Stefan; Peters, Karsten; Stevens, Bjorn; Rast, Sebastian; Schutgens, Nick; Stier, Philip</p> <p>2015-04-01</p> <p>The detailed treatment of <span class="hlt">aerosol</span> in global modeling is complex and time-consuming. Thus simplified approaches are investigated, which prescribe 4D (space and time) distributions of <span class="hlt">aerosol</span> optical properties and of <span class="hlt">aerosol</span> microphysical properties. <span class="hlt">Aerosol</span> optical properties are required to assess <span class="hlt">aerosol</span> direct radiative effects and <span class="hlt">aerosol</span> microphysical properties (in terms of their ability as <span class="hlt">aerosol</span> nuclei to modify cloud droplet concentrations) are needed to address the indirect <span class="hlt">aerosol</span> impact on cloud properties. Following the simplifying concept of the monthly gridded (1x1 lat/lon) <span class="hlt">aerosol</span> climatology (MAC), new approaches are presented and evaluated against more detailed methods, including comparisons to detailed simulations with complex <span class="hlt">aerosol</span> component modules.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20030066709&hterms=Smith+Michael&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2528Smith%252C%2BMichael%2529','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20030066709&hterms=Smith+Michael&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2528Smith%252C%2BMichael%2529"><span id="translatedtitle">THEMIS Observations of Atmospheric <span class="hlt">Aerosol</span> Optical Depth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Smith, Michael D.; Bandfield, Joshua L.; Christensen, Philip R.; Richardson, Mark I.</p> <p>2003-01-01</p> <p>The Mars Odyssey spacecraft entered into Martian orbit in October 2001 and after successful aerobraking began mapping in February 2002 (approximately Ls=330 deg.). <span class="hlt">Images</span> taken by the Thermal Emission <span class="hlt">Imaging</span> System (THEMIS) on-board the Odyssey spacecraft allow the quantitative retrieval of atmospheric dust and water-ice <span class="hlt">aerosol</span> optical depth. Atmospheric quantities retrieved from THEMIS build upon existing datasets returned by Mariner 9, Viking, and Mars Global Surveyor (MGS). Data from THEMIS complements the concurrent MGS Thermal Emission Spectrometer (TES) data by offering a later local time (approx. 2:00 for TES vs. approx. 4:00 - 5:30 for THEMIS) and much higher spatial resolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19947117','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19947117"><span id="translatedtitle">The relation between Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) <span class="hlt">aerosol</span> optical depth and PM2.5 over the United States: a geographical comparison by U.S. Environmental Protection Agency regions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Hai; Hoff, Raymond M; Engel-Cox, Jill A</p> <p>2009-11-01</p> <p><span class="hlt">Aerosol</span> optical depth (AOD) acquired from satellite measurements demonstrates good correlation with particulate matter with diameters less than 2.5 microm (PM2.5) in some regions of the United States and has been used for monitoring and nowcasting air quality over the United States. This work investigates the relation between Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) AOD and PM2.5 over the 10 U.S. Environmental Protection Agency (EPA)-defined geographic regions in the United States on the basis of a 2-yr (2005-2006) match-up dataset of MODIS AOD and hourly PM2.5 measurements. The AOD retrievals demonstrate a geographical and seasonal variation in their relation with PM2.5. Good correlations are mostly observed over the eastern United States in summer and fall. The southeastern United States has the highest correlation coefficients at more than 0.6. The southwestern United States has the lowest correlation coefficient of approximately 0.2. The seasonal regression relations derived for each region are used to estimate the PM2.5 from AOD retrievals, and it is shown that the estimation using this method is more accurate than that using a fixed ratio between PM2.5 and AOD. Two versions of AOD from Terra (v4.0.1 and v5.2.6) are also compared in terms of the inversion methods and screening algorithms. The v5.2.6 AOD retrievals demonstrate better correlation with PM2.5 than v4.0.1 retrievals, but they have much less coverage because of the differences in the cloud-screening algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/864035','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/864035"><span id="translatedtitle">Highly stable <span class="hlt">aerosol</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>DeFord, Henry S.; Clark, Mark L.</p> <p>1981-01-01</p> <p>An improved compressed air nebulizer has been developed such that a uniform <span class="hlt">aerosol</span> particle size and concentration may be produced over long time periods. This result is achieved by applying a vacuum pressure to the makeup assembly and by use of a vent tube between the atmosphere and the makeup solution. By applying appropriate vacuum pressures to the makeup solution container and by proper positioning of the vent tube, a constant level of aspirating solution may be maintained within the aspirating assembly with aspirating solution continuously replaced from the makeup solution supply. This device may also be adapted to have a plurality of <span class="hlt">aerosol</span> generators and only one central makeup assembly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7003621','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/biblio/7003621"><span id="translatedtitle">Highly stable <span class="hlt">aerosol</span> generator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>DeFord, H.S.; Clark, M.L.</p> <p>1981-11-03</p> <p>An improved compressed air nebulizer has been developed such that a uniform <span class="hlt">aerosol</span> particle size and concentration may be produced over long time periods. This result is achieved by applying a vacuum pressure to the makeup assembly and by use of a vent tube between the atmosphere and the makeup solution. By applying appropriate vacuum pressures to the makeup solution container and by proper positioning of the vent tube, a constant level of aspirating solution may be maintained within the aspirating assembly with aspirating solution continuously replaced from the makeup solution supply. This device may also be adapted to have a plurality of <span class="hlt">aerosol</span> generators and only one central makeup assembly. 2 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20020065565&hterms=extinction+consequences&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dextinction%2Bconsequences','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20020065565&hterms=extinction+consequences&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dextinction%2Bconsequences"><span id="translatedtitle">Stratospheric <span class="hlt">Aerosol</span> Measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pueschel, Rudolf, F.; Gore, Warren J. (Technical Monitor)</p> <p>1998-01-01</p> <p>Stratospheric <span class="hlt">aerosols</span> affect the atmospheric energy balance by scattering and absorbing solar and terrestrial radiation. They also can alter stratospheric chemical cycles by catalyzing heterogeneous reactions which markedly perturb odd nitrogen, chlorine and ozone levels. <span class="hlt">Aerosol</span> measurements by satellites began in NASA in 1975 with the Stratospheric <span class="hlt">Aerosol</span> Measurement (SAM) program, to be followed by the Stratospheric <span class="hlt">Aerosol</span> and Gas Experiment (SAGE) starting in 1979. Both programs employ the solar occultation, or Earth limb extinction, techniques. Major results of these activities include the discovery of polar stratospheric clouds (PSCs) in both hemispheres in winter, illustrations of the impacts of major (El Chichon 1982 and Pinatubo 1991) eruptions, and detection of a negative global trend in lower stratospheric/upper tropospheric <span class="hlt">aerosol</span> extinction. This latter result can be considered a triumph of successful worldwide sulfur emission controls. The SAGE record will be continued and improved by SAGE III, currently scheduled for multiple launches beginning in 2000 as part of the Earth Observing System (EOS). The satellite program has been supplemented by in situ measurements aboard the ER-2 (20 km ceiling) since 1974, and from the DC-8 (13 km ceiling) aircraft beginning in 1989. Collection by wire impactors and subsequent electron microscopic and X-ray energy-dispersive analyses, and optical particle spectrometry have been the principle techniques. Major findings are: (1) The stratospheric background <span class="hlt">aerosol</span> consists of dilute sulfuric acid droplets of around 0.1 micrometer modal diameter at concentration of tens to hundreds of monograms per cubic meter; (2) Soot from aircraft amounts to a fraction of one percent of the background total <span class="hlt">aerosol</span>; (3) Volcanic eruptions perturb the sulfuric acid, but not the soot, <span class="hlt">aerosol</span> abundance by several orders of magnitude; (4) PSCs contain nitric acid at temperatures below 195K, supporting chemical hypotheses</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUSM.A51A..07S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUSM.A51A..07S"><span id="translatedtitle">Microphysical properties of transported biomass burning <span class="hlt">aerosols</span> in coastal regions, and application to improving retrievals of <span class="hlt">aerosol</span> optical depth from SeaWiFS data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.</p> <p>2013-05-01</p> <p>Due to the limited measurement capabilities of heritage and current spaceborne passive <span class="hlt">imaging</span> radiometers, algorithms for the retrieval of <span class="hlt">aerosol</span> optical depth (AOD) and related quantities must make assumptions relating to <span class="hlt">aerosol</span> microphysical properties and surface reflectance. Over the ocean, surface reflectance can be relatively well-modelled, but knowledge of <span class="hlt">aerosol</span> properties can remain elusive. Several field campaigns and many studies have examined the microphysical properties of biomass burning (smoke) <span class="hlt">aerosol</span>. However, these largely focus on properties over land and near to the source regions. In coastal and open-ocean regions the properties of transported smoke may differ, due to factors such as <span class="hlt">aerosol</span> aging, wet/dry deposition, and mixture with other <span class="hlt">aerosol</span> sources (e.g. influence of maritime, pollution, or mineral dust <span class="hlt">aerosols</span>). Hence, models based on near-source <span class="hlt">aerosol</span> observations may be less representative of such transported smoke <span class="hlt">aerosols</span>, introducing additional uncertainty into satellite retrievals of <span class="hlt">aerosol</span> properties. This study examines case studies of transported smoke from select globally-distributed coastal and island <span class="hlt">Aerosol</span> Robotic Network (AERONET) sites. These are used to inform improved models for over-ocean transported smoke <span class="hlt">aerosol</span> for AOD retrievals from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). These models are used in an updated version of the SeaWiFS Ocean <span class="hlt">Aerosol</span> Retrieval (SOAR) algorithm, which has been combined with the Deep Blue algorithm over land to create a 13-year (1997-2010) high-quality record of AOD over land and ocean. Applying these algorithms to other sensors will enable the creation of a long-term global climate data record of spectral AOD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1058438','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1058438"><span id="translatedtitle">Effect of Air Ions on Submicron T1 Bacteriophage <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Happ, John W.; Harstad, J. Bruce; Buchanan, Lee M.</p> <p>1966-01-01</p> <p>The effect of a high concentration of ionized air molecules on sampling T1 phage <span class="hlt">aerosols</span> of submicron particle size was evaluated by comparing the phage recoveries of all-glass impingers (AGI-4) and type 6 filter papers. Sampler recoveries of all ionized <span class="hlt">aerosols</span> were less than the recoveries of nonionized control <span class="hlt">aerosols</span>. These reductions in recovery were greater with positive ions than with negative ions or ions of mixed polarity. The AGI-4 allowed considerable slippage, which was not affected by the air ions. Type 6 filter paper recoveries were less than AGI-4 recoveries. The air ions did not appear to affect the <span class="hlt">aerosol</span> particle size as determined by an electron microscope. <span class="hlt">Images</span> Fig. 1 Fig. 3 PMID:16349691</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=377156','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=377156"><span id="translatedtitle">Naval Biomedical Research Laboratory, Programmed Environment, <span class="hlt">Aerosol</span> Facility</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Goldberg, L. J.</p> <p>1971-01-01</p> <p>Mathematical considerations of the behavior of <span class="hlt">aerosolized</span> particles in a rotating drum are presented, and the rotating drum as an <span class="hlt">aerosol</span>-holding device is compared with a stirred settling chamber. The basic overall design elements of a facility employing eight rotating drums are presented. This facility provides an environment in which temperature can be maintained within 0.5 F (0.25 C) of any set point over a range of 50 to 120 F (10 to 49 C); concomitantly the relative humidity within any selected drum may be controlled in a nominal range of 0 to 90%. Some of the major technical aspects of operating this facility are also presented, including handling of air support systems, <span class="hlt">aerosol</span> production, animal exposure, <span class="hlt">aerosol</span> monitoring, and sampling. <span class="hlt">Images</span> PMID:5549701</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010119957','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010119957"><span id="translatedtitle">Validation of MODIS <span class="hlt">Aerosol</span> Optical Depth Retrieval Over Land</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chu, D. A.; Kaufman, Y. J.; Ichoku, C.; Remer, L. A.; Tanre, D.; Holben, B. N.; Einaudi, Franco (Technical Monitor)</p> <p>2001-01-01</p> <p><span class="hlt">Aerosol</span> optical depths are derived operationally for the first time over land in the visible wavelengths by MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) onboard the EOSTerra spacecraft. More than 300 Sun photometer data points from more than 30 AERONET (<span class="hlt">Aerosol</span> Robotic Network) sites globally were used in validating the <span class="hlt">aerosol</span> optical depths obtained during July - September 2000. Excellent agreement is found with retrieval errors within (Delta)tau=+/- 0.05 +/- 0.20 tau, as predicted, over (partially) vegetated surfaces, consistent with pre-launch theoretical analysis and aircraft field experiments. In coastal and semi-arid regions larger errors are caused predominantly by the uncertainty in evaluating the surface reflectance. The excellent fit was achieved despite the ongoing improvements in instrument characterization and calibration. This results show that MODIS-derived <span class="hlt">aerosol</span> optical depths can be used quantitatively in many applications with cautions for residual clouds, snow/ice, and water contamination.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20030112095&hterms=Dutch&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DDutch','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20030112095&hterms=Dutch&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DDutch"><span id="translatedtitle">Measuring <span class="hlt">Aerosol</span> Optical Properties with the Ozone Monitoring Instrument (OMI)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Veefkind, J. P.; Torres, O.; Syniuk, A.; Decae, R.; deLeeuw, G.</p> <p>2003-01-01</p> <p>The Ozone Monitoring Instrument (OMI) is the Dutch-Finnish contribution to the NASA EOS-Aura mission scheduled for launch in January 2004. OM1 is an <span class="hlt">imaging</span> spectrometer that will measure the back-scattered Solar radiance between 270 an 500 nm. With its relatively high spatial resolution (13x24 sq km at nadir) and daily global coverage. OM1 will make a major contribution to our understanding of atmospheric chemistry and to climate research. OM1 will provide data continuity with the TOMS instruments. One of the pleasant surprises of the TOMS data record was its information on <span class="hlt">aerosol</span> properties. First, only the absorbing <span class="hlt">aerosol</span> index, which is sensitive to elevated lay- ers of <span class="hlt">aerosols</span> such as desert dust and smoke <span class="hlt">aerosols</span>, was derived. Recently these methods were further improved to yield <span class="hlt">aerosol</span> optical thickness and single scattering albedo over land and ocean for 19 years of TOMS data (1979-1992,1997-2002), making it one of the longest and most valuable time series for <span class="hlt">aerosols</span> presently available. Such long time series are essential to quantify the effect of <span class="hlt">aerosols</span> on the Earth& climate. The OM1 instrument is better suited to measure <span class="hlt">aerosols</span> than the TOMS instruments because of the smaller footprint, and better spectral coverage. The better capabilities of OMI will enable us to provide an improved <span class="hlt">aerosol</span> product, but the knowledge will also be used for further analysis of the <span class="hlt">aerosol</span> record from TOMS. The OM1 <span class="hlt">aerosol</span> product that is currently being developed for OM1 combines the TOMS experience and the multi-spectral techniques that are used in the visible and near infrared. The challenge for this new product is to provide <span class="hlt">aerosol</span> optical thickness and single scattering albedo from the near ultraviolet to the visible (330-500 nm) over land and ocean. In this presentation the methods for deriving the OM1 <span class="hlt">aerosol</span> product will be presented. Part of these methods developed for OM1 can already be applied to TOMS data and results of such analysis will be shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRD..120.8890R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRD..120.8890R"><span id="translatedtitle">Merging the OSIRIS and SAGE II stratospheric <span class="hlt">aerosol</span> records</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rieger, L. A.; Bourassa, A. E.; Degenstein, D. A.</p> <p>2015-09-01</p> <p>The Optical Spectrograph and InfraRed <span class="hlt">Imaging</span> System (OSIRIS) instrument on the Odin satellite, launched in 2001 and currently operational, measures limb-scattered sunlight from which profiles of stratospheric <span class="hlt">aerosol</span> extinction are retrieved. The Stratospheric <span class="hlt">Aerosol</span> and Gas Experiment (SAGE) II was launched in 1984 and provided measurements of stratospheric <span class="hlt">aerosol</span> extinction until mid-2005. This provides approximately 4 years of mission overlap which has allowed us to consistently extend the SAGE II version 7.00 record to the present using OSIRIS <span class="hlt">aerosol</span> extinction retrievals. In this work we first compare coincident <span class="hlt">aerosol</span> extinction observations during the overlap period by interpolating the SAGE II 525nm and 1020nm channels to the OSIRIS extinction wavelength of 750nm. In the tropics to midlatitudes mean differences are typically less than 10%, although larger biases are seen at higher latitudes and at altitudes outside the main <span class="hlt">aerosol</span> layer. OSIRIS <span class="hlt">aerosol</span> extinction retrievals at 750nm are used to create a monthly time series zonally averaged in 5°bins and qualitatively compared to SAGE II 525nm observations averaged in the same way. The OSIRIS time series is then translated to 525nm with an Ângström exponent relation and bias corrected. For most locations, this provides agreement during the overlap time period to better than 15%. Uncertainty in the resulting OSIRIS time series is estimated through a series of simulation studies over the range of <span class="hlt">aerosol</span> particle size distributions observed by in situ balloon instruments and is found to be approximately 20% for background and moderately volcanic <span class="hlt">aerosol</span> loading conditions for the majority of OSIRIS measurement conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AMT.....8.1157L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AMT.....8.1157L"><span id="translatedtitle">Improving satellite-retrieved <span class="hlt">aerosol</span> microphysical properties using GOCART data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, S.; Kahn, R.; Chin, M.; Garay, M. J.; Liu, Y.</p> <p>2015-03-01</p> <p>The Multi-angle <span class="hlt">Imaging</span> SpectroRadiometer (MISR) aboard the NASA Earth Observing System's Terra satellite can provide more reliable <span class="hlt">aerosol</span> optical depth (AOD) and better constraints on particle size (Ångström exponent, or ANG), sphericity, and single-scattering albedo (SSA) than many other satellite instruments. However, many <span class="hlt">aerosol</span> mixtures pass the algorithm acceptance criteria, yielding a poor constraint, when the particle-type information in the MISR radiances is low, typically at low AOD. We investigate adding value to the MISR <span class="hlt">aerosol</span> product under these conditions by filtering the list of MISR-retrieved mixtures based on agreement between the mixture ANG and absorbing AOD (AAOD) values, and simulated <span class="hlt">aerosol</span> properties from the Goddard Chemistry <span class="hlt">Aerosol</span> Radiation and Transport (GOCART) model. MISR-GOCART ANG difference and AAOD ratio thresholds for applying GOCART constraints were determined based on coincident AOD, ANG, and AAOD measurements from the <span class="hlt">AErosol</span> RObotic NETwork (AERONET). The results were validated by comparing the adjusted MISR <span class="hlt">aerosol</span> optical properties over the contiguous USA between 2006 and 2009 with additional AERONET data. The correlation coefficient (r) between the adjusted MISR ANG derived from this study and AERONET improves to 0.45, compared to 0.29 for the MISR Version 22 standard product. The ratio of the adjusted MISR AAOD to AERONET increases to 0.74, compared to 0.5 for the MISR operational retrieval. These improvements occur primarily when AOD < 0.2 for ANG and AOD < 0.5 for AAOD. Spatial and temporal differences among the <span class="hlt">aerosol</span> optical properties of MISR V22, GOCART, and the adjusted MISR are traced to (1) GOCART underestimation of AOD and ANG in polluted regions; (2) <span class="hlt">aerosol</span> mixtures lacking in the MISR Version 22 algorithm climatology; (3) low MISR sensitivity to particle type under some conditions; and (4) parameters and thresholds used in our method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1089860','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1089860"><span id="translatedtitle">Geometrical Optics of Dense <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hay, Michael J.; Valeo, Ernest J.; Fisch, Nathaniel J.</p> <p>2013-04-24</p> <p>Assembling a free-standing, sharp-edged slab of homogeneous material that is much denser than gas, but much more rare ed than a solid, is an outstanding technological challenge. The solution may lie in focusing a dense <span class="hlt">aerosol</span> to assume this geometry. However, whereas the geometrical optics of dilute <span class="hlt">aerosols</span> is a well-developed fi eld, the dense <span class="hlt">aerosol</span> limit is mostly unexplored. Yet controlling the geometrical optics of dense <span class="hlt">aerosols</span> is necessary in preparing such a material slab. Focusing dense <span class="hlt">aerosols</span> is shown here to be possible, but the nite particle density reduces the eff ective Stokes number of the flow, a critical result for controlled focusing. __________________________________________________</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRD..117.4209N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRD..117.4209N"><span id="translatedtitle">Simulation of South Asian <span class="hlt">aerosols</span> for regional climate studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nair, Vijayakumar S.; Solmon, Fabien; Giorgi, Filippo; Mariotti, Laura; Babu, S. Suresh; Moorthy, K. Krishna</p> <p>2012-02-01</p> <p>Extensive intercomparison of columnar and near-surface <span class="hlt">aerosols</span>, simulated over the South Asian domain using the <span class="hlt">aerosol</span> module included in the regional climate model (RegCM4) of the Abdus Salam International Centre for Theoretical Physics (ICTP) have been carried out using ground-based network of Sun/sky <span class="hlt">Aerosol</span> Robotic Network (AERONET) radiometers, satellite sensors such as Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) and Multiangle <span class="hlt">Imaging</span> Spectroradiometer (MISR), and ground-based black carbon (BC) measurements made at <span class="hlt">Aerosol</span> Radiative Forcing over India (ARFI) network stations. In general, RegCM4 simulations reproduced the spatial and seasonal characteristics of <span class="hlt">aerosol</span> optical depth over South Asia reasonably well, particularly over west Asia, where mineral dust is a major contributor to the total <span class="hlt">aerosol</span> loading. In contrast, RegCM4 simulations drastically underestimated the BC mass concentrations over most of the stations, by a factor of 2 to 5, with a large spatial variability. Seasonally, the discrepancy between the measured and simulated BC tended to be higher during winter and periods when the atmospheric boundary layer is convectively stable (such as nighttime and early mornings), while during summer season and during periods when the boundary layer is convectively unstable (daytime) the discrepancies were much lower, with the noontime values agreeing very closely with the observations. A detailed analysis revealed that the model does not reproduce the nocturnal high in BC, observed at most of the Indian sites especially during winter, because of the excessive vertical transport of <span class="hlt">aerosols</span> under stable boundary layer conditions. As far as the vertical distribution was concerned, the simulated vertical profiles of BC agreed well with airborne measurements during daytime. This comprehensive validation exercise reveals the strengths and weaknesses of the model in simulating the spatial and temporal heterogeneities of the <span class="hlt">aerosol</span> fields over</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1250847','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1250847"><span id="translatedtitle"><span class="hlt">Image</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Marsh, Amber; Harsch, Tim; Pitt, Julie; Firpo, Mike; Lekin, April; Pardes, Elizabeth</p> <p>2007-08-31</p> <p>The computer side of the <span class="hlt">IMAGE</span> project consists of a collection of Perl scripts that perform a variety of tasks; scripts are available to insert, update and delete data from the underlying Oracle database, download data from NCBI's Genbank and other sources, and generate data files for download by interested parties. Web scripts make up the tracking interface, and various tools available on the project web-site (<span class="hlt">image</span>.llnl.gov) that provide a search interface to the database.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970024878','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970024878"><span id="translatedtitle">Satellite Estimates of the Direct Radiative Forcing of Biomass Burning <span class="hlt">Aerosols</span> Over South America and Africa</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Christopher, Sundar A.; Wang, Min; Kliche, Donna V.; Berendes, Todd; Welch, Ronald M.; Yang, S.K.</p> <p>1997-01-01</p> <p>Atmospheric <span class="hlt">aerosol</span> particles, both natural and anthropogenic are important to the earth's radiative balance. Therefore it is important to provide adequate validation information on the spatial, temporal and radiative properties of <span class="hlt">aerosols</span>. This will enable us to predict realistic global estimates of <span class="hlt">aerosol</span> radiative effects more confidently. The current study utilizes 66 AVHRR LAC (Local Area Coverage) and coincident Earth Radiation Budget Experiment (ERBE) <span class="hlt">images</span> to characterize the fires, smoke and radiative forcings of biomass burning <span class="hlt">aerosols</span> over four major ecosystems of South America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37.1552K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37.1552K"><span id="translatedtitle">Mesospheric <span class="hlt">aerosol</span> sampling spectrometer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knappmiller, Scott; Robertson, Scott; Sternovsky, Zoltan; Horanyi, Mihaly; Kohnert, Rick</p> <p></p> <p>. The Mesospheric <span class="hlt">Aerosol</span> Sampling Spectrometer (MASS) instrument has been launched on two sounding rockets in August, 2007 from Andoya, Norway to detect charged sub-visible <span class="hlt">aerosol</span> particles in the polar mesosphere. The MASS instrument is designed to collect charged <span class="hlt">aerosols</span>, cluster ions, and electrons on four pairs of graphite electrodes, three of which are biased with increasing voltage. The design of the MASS instrument was complicated by the short mean free path in the mesosphere. The opening to MASS was deliberately built to increase the mean free path and to reduce the shock wave within the instrument. The design procedure began with aerodynamics simulations of the flow through the instrument using Direct Simulation Monte Carlo (DSMC) in 3-D. The electric fields within the instrument were calculated using a Laplace solver in 3-D. With the aerodynamic and electric field simulations completed, an algorithm was created to find the trajectories of charged <span class="hlt">aerosols</span> including collisions within MASS. Using this algorithm the collection efficiencies for each electrode was calculated as a function of the charge to mass ratio of the incoming particle. The simulation results have been confirmed experimentally using an Argon RF ion beam. The data from the August launches have been analyzed and the initial results show the MASS instrument operated as expected. Additional studies are underway to determine if there were effects from payload charging or spurious charge generation within the instrument. This project is supported by NASA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008PhDT........60D&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008PhDT........60D&link_type=ABSTRACT"><span id="translatedtitle">An experimental study of dense <span class="hlt">aerosol</span> aggregations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dhaubhadel, Rajan</p> <p></p> <p>We demonstrated that an <span class="hlt">aerosol</span> can gel. This gelation was then used for a one-step method to produce an ultralow density porous carbon or silica material. This material was named an <span class="hlt">aerosol</span> gel because it was made via gelation of particles in the <span class="hlt">aerosol</span> phase. The carbon and silica <span class="hlt">aerosol</span> gels had high specific surface area (200--350 sq m2/g for carbon and 300--500 sq m2/g for silica) and an extremely low density (2.5--6.0 mg/cm3), properties similar to conventional aerogels. Key aspects to form a gel from an <span class="hlt">aerosol</span> are large volume fraction, ca. 10-4 or greater, and small primary particle size, 50 nm or smaller, so that the gel time is fast compared to other characteristic times. Next we report the results of a study of the cluster morphology and kinetics of a dense aggregating <span class="hlt">aerosol</span> system using the small angle light scattering technique. The soot particles started as individual monomers, ca. 38 nm radius, grew to bigger clusters with time and finally stopped evolving after spanning a network across the whole system volume. This spanning is <span class="hlt">aerosol</span> gelation. The gelled system showed a hybrid morphology with a lower fractal dimension at length scales of a micron or smaller and a higher fractal dimension at length scales greater than a micron. The study of the kinetics of the aggregating system showed that when the system gelled, the aggregation kernel homogeneity lambda attained a value 0.4 or higher. The magnitude of the aggregation kernel showed an increase with increasing volume fraction. We also used <span class="hlt">image</span> analysis technique to study the cluster morphology. From the digitized pictures of soot clusters the cluster morphology was determined by two different methods: structure factor and perimeter analysis. We find a hybrid, superaggregate morphology characterized by a fractal dimension of Df ≈ to 1.8 between the monomer size, ca. 50 nm, and 1 mum micron and Df ≈ to 2.6 at larger length scales up to ˜ 10 mum. The superaggregate morphology is a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4448264','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4448264"><span id="translatedtitle">New breast cancer prognostic factors identified by computer-aided <span class="hlt">image</span> analysis of HE stained histopathology <span class="hlt">images</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chen, Jia-Mei; Qu, Ai-Ping; Wang, Lin-Wei; Yuan, Jing-Ping; Yang, Fang; Xiang, Qing-Ming; Maskey, Ninu; Yang, Gui-Fang; Liu, Juan; Li, Yan</p> <p>2015-01-01</p> <p>Computer-aided <span class="hlt">image</span> analysis (<span class="hlt">CAI</span>) can help objectively quantify morphologic features of hematoxylin-eosin (HE) histopathology <span class="hlt">images</span> and provide potentially useful prognostic information on breast cancer. We performed a <span class="hlt">CAI</span> workflow on 1,150 HE <span class="hlt">images</span> from 230 patients with invasive ductal carcinoma (IDC) of the breast. We used a pixel-wise support vector machine classifier for tumor nests (TNs)-stroma segmentation, and a marker-controlled watershed algorithm for nuclei segmentation. 730 morphologic parameters were extracted after segmentation, and 12 parameters identified by Kaplan-Meier analysis were significantly associated with 8-year disease free survival (P < 0.05 for all). Moreover, four <span class="hlt">image</span> features including TNs feature (HR 1.327, 95%CI [1.001 - 1.759], P = 0.049), TNs cell nuclei feature (HR 0.729, 95%CI [0.537 - 0.989], P = 0.042), TNs cell density (HR 1.625, 95%CI [1.177 - 2.244], P = 0.003), and stromal cell structure feature (HR 1.596, 95%CI [1.142 - 2.229], P = 0.006) were identified by multivariate Cox proportional hazards model to be new independent prognostic factors. The results indicated that <span class="hlt">CAI</span> can assist the pathologist in extracting prognostic information from HE histopathology <span class="hlt">images</span> for IDC. The TNs feature, TNs cell nuclei feature, TNs cell density, and stromal cell structure feature could be new prognostic factors. PMID:26022540</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26022540','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26022540"><span id="translatedtitle">New breast cancer prognostic factors identified by computer-aided <span class="hlt">image</span> analysis of HE stained histopathology <span class="hlt">images</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Jia-Mei; Qu, Ai-Ping; Wang, Lin-Wei; Yuan, Jing-Ping; Yang, Fang; Xiang, Qing-Ming; Maskey, Ninu; Yang, Gui-Fang; Liu, Juan; Li, Yan</p> <p>2015-05-29</p> <p>Computer-aided <span class="hlt">image</span> analysis (<span class="hlt">CAI</span>) can help objectively quantify morphologic features of hematoxylin-eosin (HE) histopathology <span class="hlt">images</span> and provide potentially useful prognostic information on breast cancer. We performed a <span class="hlt">CAI</span> workflow on 1,150 HE <span class="hlt">images</span> from 230 patients with invasive ductal carcinoma (IDC) of the breast. We used a pixel-wise support vector machine classifier for tumor nests (TNs)-stroma segmentation, and a marker-controlled watershed algorithm for nuclei segmentation. 730 morphologic parameters were extracted after segmentation, and 12 parameters identified by Kaplan-Meier analysis were significantly associated with 8-year disease free survival (P < 0.05 for all). Moreover, four <span class="hlt">image</span> features including TNs feature (HR 1.327, 95%CI [1.001-1.759], P = 0.049), TNs cell nuclei feature (HR 0.729, 95%CI [0.537-0.989], P = 0.042), TNs cell density (HR 1.625, 95%CI [1.177-2.244], P = 0.003), and stromal cell structure feature (HR 1.596, 95%CI [1.142-2.229], P = 0.006) were identified by multivariate Cox proportional hazards model to be new independent prognostic factors. The results indicated that <span class="hlt">CAI</span> can assist the pathologist in extracting prognostic information from HE histopathology <span class="hlt">images</span> for IDC. The TNs feature, TNs cell nuclei feature, TNs cell density, and stromal cell structure feature could be new prognostic factors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.9605K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.9605K"><span id="translatedtitle">Development of <span class="hlt">aerosol</span> retrieval algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Mijin; Kim, Jhoon; Park, Sang Seo; Jeong, Ukkyo; Ahn, Changwoo; Bhartia, Pawan. K.; Torres, Omar; Song, Chang-Keun; Han, Jin-Seok</p> <p>2014-05-01</p> <p>A scanning UV-Visible spectrometer, the GEMS (Geostationary Environment Monitoring Spectrometer) onboard the GEO-KOMPSAT2B (Geostationary Korea Multi-Purpose Satellite) is planned to be launched in geostationary orbit in 2018. The GEMS employs hyper-spectral <span class="hlt">imaging</span> with 0.6 nm resolution to observe solar backscatter radiation in the UV and Visible range. In the UV range, the low surface contribution to the backscattered radiation and strong interaction between <span class="hlt">aerosol</span> absorption and molecular scattering can be advantageous in retrieving <span class="hlt">aerosol</span> optical properties such as <span class="hlt">aerosol</span> optical depth (AOD) and single scattering albedo (SSA). This study presents a UV-VIS algorithm to retrieve AOD and SSA from GEMS. The algorithm is based on the general inversion method, which uses pre-calculated look-up table (LUT) with assumed <span class="hlt">aerosol</span> properties and measurement condition. To calculate LUT, <span class="hlt">aerosol</span> optical properties over Asia [70°E-145°E, 0°N-50°N] are obtained from AERONET inversion data (level 2.0) at 46 AERONET sites, and are applied to VLIDORT (spur, 2006). Because the backscattering radiance in UV-Visible range has significant sensitivity to radiance absorptivity and size distribution of loading <span class="hlt">aerosol</span>, <span class="hlt">aerosol</span> types are classified from AERONET inversion data by using <span class="hlt">aerosol</span> classification method suggested in Lee et al. (2010). Then the LUTs are calculated with average optical properties for each <span class="hlt">aerosol</span> type. The GEMS <span class="hlt">aerosol</span> algorithm is tested with OMI level-1B dataset, a provisional data for GEMS measurement. The <span class="hlt">aerosol</span> types for each measured scene are selected by using both of UVAI and VISAI, and AOD and SSA are simultaneously retrieved by comparing simulated radiance with selected <span class="hlt">aerosol</span> type and the measured value. The AOD and SSA retrieved from GEMS <span class="hlt">aerosol</span> algorithm are well matched with OMI products, although the retrieved AOD is slightly higher than OMI value. To detect cloud pixel, spatial standard deviation test of radiance is applied in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20160012702&hterms=Ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DOcean','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20160012702&hterms=Ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DOcean"><span id="translatedtitle"><span class="hlt">Aerosol</span> Optical Depth Distribution in Extratropical Cyclones over the Northern Hemisphere Oceans</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Naud, Catherine M.; Posselt, Derek J.; van den Heever, Susan C.</p> <p>2016-01-01</p> <p>Using Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer and an extratropical cyclone database,the climatological distribution of <span class="hlt">aerosol</span> optical depth (AOD) in extratropical cyclones is explored based solely on observations. Cyclone-centered composites of <span class="hlt">aerosol</span> optical depth are constructed for the Northern Hemisphere mid-latitude ocean regions, and their seasonal variations are examined. These composites are found to be qualitatively stable when the impact of clouds and surface insolation or brightness is tested. The larger AODs occur in spring and summer and are preferentially found in the warm frontal and in the post-cold frontal regions in all seasons. The fine mode <span class="hlt">aerosols</span> dominate the cold sector AODs, but the coarse mode <span class="hlt">aerosols</span> display large AODs in the warm sector. These differences between the <span class="hlt">aerosol</span> modes are related to the varying source regions of the <span class="hlt">aerosols</span> and could potentially have different impacts on cloud and precipitation within the cyclones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.2259M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.2259M"><span id="translatedtitle">Spatial boundaries of <span class="hlt">Aerosol</span> Robotic Network observations over the Mediterranean basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mishra, A. K.; Rudich, Y.; Koren, I.</p> <p>2016-03-01</p> <p>Accurate knowledge of <span class="hlt">aerosol</span> variability on a relatively high spatiotemporal scale is needed for better assessment of <span class="hlt">aerosol</span> radiative effects and <span class="hlt">aerosol</span>-climate interactions. We investigated the spatial boundaries of the <span class="hlt">Aerosol</span> Robotic Network (AERONET) observations over the Mediterranean basin using a statistical approach. We used 13 years (2002-2014) of <span class="hlt">aerosol</span> optical depth (AOD) measurements from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) and 15 AERONET sites around the Mediterranean basin. The gridded correlation maps show moderate to high correlations (R > 0.5) around each AERONET site up to ~200-500 km radius depending on location. Such analyses provide information on the spatial domain in which the AERONET measurements can be reliably used per site. The statistical model provides a better daytime AOD product on finer temporal resolution with higher spatial coverage as compared to using AERONET/MODIS observations separately. The findings from this study can be useful for the assimilation-based model forecasting of <span class="hlt">aerosol</span> properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.A11E0090P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.A11E0090P"><span id="translatedtitle">MISR <span class="hlt">Aerosol</span> Air Mass Type Mapping over Mega-City: Validation and Applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patadia, F.; Kahn, R. A.</p> <p>2010-12-01</p> <p>Most <span class="hlt">aerosol</span> air-quality monitoring in mega-city environments is done from scattered ground stations having detailed chemical and optical sampling capabilities. Satellite instruments such as the Multi-angle <span class="hlt">Imaging</span> SpectroRadiometer (MISR) can retrieve total-column <span class="hlt">Aerosol</span> Optical Depth (AOD), along with some information about particle microphysical properties. Although the particle property information from MISR is much less detailed than that obtained from the ground sampling stations, the coverage is extensive, making it possible to put individual surface observations into the context of regional <span class="hlt">aerosol</span> air mass types. This paper presents an analysis of MISR <span class="hlt">aerosol</span> observations made coincident with aircraft and ground-based instruments during the INTEX-B field campaign. These detailed comparisons of satellite <span class="hlt">aerosol</span> property retrievals against dedicated field measurements provide the opportunity to validate the retrievals quantitatively at a regional level, and help to improve <span class="hlt">aerosol</span> representation in retrieval algorithms. Validation of MISR retrieved AOD and other <span class="hlt">aerosol</span> properties over the INTEX-B study region in and around Mexico City will be presented. MISR’s ability to distinguish among <span class="hlt">aerosol</span> air mass types will be discussed. The goal of this effort is to use the MISR <span class="hlt">aerosol</span> property retrievals for mapping both <span class="hlt">aerosol</span> air mass type and AOD gradients in mega-city environments over the decade-plus that MISR has made global observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150019918','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150019918"><span id="translatedtitle">Retrieving the Height of Smoke and Dust <span class="hlt">Aerosols</span> by Synergistic Use of VIIRS, OMPS, and CALIOP Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lee, Jaehwa; Hsu, N. Christina; Bettenhausen, Corey; Sayer, Andrew M.; Seftor, Colin J.; Jeong, Myeong-Jae</p> <p>2015-01-01</p> <p><span class="hlt">Aerosol</span> Single scattering albedo and Height Estimation (ASHE) algorithm was first introduced in Jeong and Hsu (2008) to provide <span class="hlt">aerosol</span> layer height as well as single scattering albedo (SSA) for biomass burning smoke <span class="hlt">aerosols</span>. One of the advantages of this algorithm was that the <span class="hlt">aerosol</span> layer height can be retrieved over broad areas, which had not been available from lidar observations only. The algorithm utilized <span class="hlt">aerosol</span> properties from three different satellite sensors, i.e., <span class="hlt">aerosol</span> optical depth (AOD) and Ångström exponent (AE) from Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), UV <span class="hlt">aerosol</span> index (UVAI) from Ozone Monitoring Instrument (OMI), and <span class="hlt">aerosol</span> layer height from Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization (CALIOP). Here, we extend the application of the algorithm to Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS) and Ozone Mapping and Profiler Suite (OMPS) data. We also now include dust layers as well as smoke. Other updates include improvements in retrieving the AOD of nonspherical dust from VIIRS, better determination of the <span class="hlt">aerosol</span> layer height from CALIOP, and more realistic input <span class="hlt">aerosol</span> profiles in the forward model for better accuracy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21096848','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21096848"><span id="translatedtitle">New principles in nuclear medicine <span class="hlt">imaging</span>: a full aperture stereoscopic <span class="hlt">imaging</span> technique.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Strocovsky, Sergio G; Otero, Dino</p> <p>2010-01-01</p> <p>In nuclear medicine, <span class="hlt">images</span> of planar scintigraphy and single photon emission computerized tomography (SPECT) obtained through gamma camera (GC) appear to be blurred. Alternatively, coded aperture <span class="hlt">imaging</span> (<span class="hlt">CAI</span>) can surpass the quality of GC <span class="hlt">images</span>, but still it is not extensively used due to the decoding complexity of some <span class="hlt">images</span> and the difficulty in controlling the noise. Summing up, the <span class="hlt">images</span> obtained through GC are low quality and it is still difficult to implement <span class="hlt">CAI</span> technique. Here we present a full aperture <span class="hlt">imaging</span> (FAI) technique which overcomes the problems of <span class="hlt">CAI</span> ordinary systems. The gamma radiation transmitted through a large single aperture is edge-encoded, taking advantage of the fact that nuclear radiation is spatially incoherent. The novel technique is tested by means of Monte Carlo method with simple and complex sources. Spatial resolution tests and parallax tests of GC versus FAI were made, and three-dimensional capacities of GC versus FAI were analyzed. Simulations have allowed comparison of both techniques under ideal, identical conditions. The results show that FAI technique has greater sensitivity (approximately 100 times) and greater spatial resolution (>2.6 times at 40 cm source-detector distance) than that of GC. FAI technique allows to obtain <span class="hlt">images</span> with typical resolution of GC short source-detector distance but at longer source-detector distance. The FAI decoding algorithm simultaneously reconstructs four different projections, while GC produces only one projection per acquisition. Our results show it is possible to apply an extremely simple encoded <span class="hlt">imaging</span> technique, and get three-dimensional radioactivity information. Thus GC-based systems could be substituted, given that FAI technique is simple and it produces four <span class="hlt">images</span> which may feed stereoscopic systems, substituting in some cases, tomographic reconstructions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20030112782&hterms=competence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcompetence','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20030112782&hterms=competence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcompetence"><span id="translatedtitle">Synergism of MODIS <span class="hlt">Aerosol</span> Remote Sensing from Terra and Aqua</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ichoku, Charles; Kaufman, Yoram J.; Remer, Lorraine A.</p> <p>2003-01-01</p> <p>The MODerate-resolution <span class="hlt">Imaging</span> Spectro-radiometer (MODIS) sensors, aboard the Earth Observing System (EOS) Terra and Aqua satellites, are showing excellent competence at measuring the global distribution and properties of <span class="hlt">aerosols</span>. Terra and Aqua were launched on December 18, 1999 and May 4, 2002 respectively, with daytime equator crossing times of approximately 10:30 am and 1:30 pm respectively. Several <span class="hlt">aerosol</span> parameters are retrieved at 10-km spatial resolution from MODIS daytime data over land and ocean surfaces. The parameters retrieved include: <span class="hlt">aerosol</span> optical thickness (AOT) at 0.47, 0.55 and 0.66 micron wavelengths over land, and at 0.47, 0.55, 0.66, 0.87, 1.2, 1.6, and 2.1 microns over ocean; Angstrom exponent over land and ocean; and effective radii, and the proportion of AOT contributed by the small mode <span class="hlt">aerosols</span> over ocean. Since the beginning of its operation, the quality of Terra-MODIS <span class="hlt">aerosol</span> products (especially AOT) have been evaluated periodically by cross-correlation with equivalent data sets acquired by ground-based (and occasionally also airborne) sunphotometers, particularly those coordinated within the framework of the <span class="hlt">AErosol</span> Robotic NETwork (AERONET). Terra-MODIS AOT data have been found to meet or exceed pre-launch accuracy expectations, and have been applied to various studies dealing with local, regional, and global <span class="hlt">aerosol</span> monitoring. The results of these Terra-MODIS <span class="hlt">aerosol</span> data validation efforts and studies have been reported in several scientific papers and conferences. Although Aqua-MODIS is still young, it is already yielding formidable <span class="hlt">aerosol</span> data products, which are also subjected to careful periodic evaluation similar to that implemented for the Terra-MODIS products. This paper presents results of validation of Aqua-MODIS <span class="hlt">aerosol</span> products with AERONET, as well as comparative evaluation against corresponding Terra-MODIS data. In addition, we show interesting independent and synergistic applications of MODIS <span class="hlt">aerosol</span> data from</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.3521W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.3521W"><span id="translatedtitle">Anthropogenic <span class="hlt">Aerosols</span> and Tropical Precipitation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, C.; Kim, D.; Ekman, A. M. L.; Barth, M. C.; Rasch, P. J.</p> <p>2009-04-01</p> <p>Anthropogenic <span class="hlt">aerosols</span> can affect the radiative balance of the Earth-atmosphere system and precipitation by acting as cloud condensation nuclei (CCN) or ice nuclei (IN) and thus modifying the optical and microphysical properties as well as lifetimes of clouds. Recent studies have also suggested that the direct radiative effect of anthropogenic <span class="hlt">aerosols</span>, particularly absorbing <span class="hlt">aerosols</span>, can perturb the large-scale circulation and cause a significant change in both quantity and distribution of critical tropical precipitation systems ranging from Pacific and Indian to Atlantic Oceans. This effect of <span class="hlt">aerosols</span> on precipitation often appears in places away from <span class="hlt">aerosol</span>-concentrated regions and current results suggest that the precipitation changes caused by it could be much more substantial than that by the microphysics-based <span class="hlt">aerosol</span> effect. To understand the detailed mechanisms and strengths of such a "remote impact" and the climate response/feedback to anthropogenic <span class="hlt">aerosols</span> in general, an interactive <span class="hlt">aerosol</span>-climate model has been developed based on the Community Climate System Model (CCSM) of NCAR. Its <span class="hlt">aerosol</span> module describes size, chemical composition, and mixing states of various sulfate and carbonaceous <span class="hlt">aerosols</span>. Several model processes are derived based on 3D cloud-resolving model simulations. We have conducted a set of long integrations using the model driven by radiative effects of different combinations of various carbonaceous and sulfate <span class="hlt">aerosols</span> and their mixtures. The responses of tropical precipitation systems to the forcing of these <span class="hlt">aerosols</span> are analyzed using both model and observational data. Detailed analyses on the <span class="hlt">aerosol</span>-precipitation causal relations of two systems: i.e., the Indian summer monsoon and Pacific ITCZ will be specifically presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACP....15.5903P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACP....15.5903P"><span id="translatedtitle">A multi-model evaluation of <span class="hlt">aerosols</span> over South Asia: common problems and possible causes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pan, X.; Chin, M.; Gautam, R.; Bian, H.; Kim, D.; Colarco, P. R.; Diehl, T. L.; Takemura, T.; Pozzoli, L.; Tsigaridis, K.; Bauer, S.; Bellouin, N.</p> <p>2015-05-01</p> <p>Atmospheric pollution over South Asia attracts special attention due to its effects on regional climate, water cycle and human health. These effects are potentially growing owing to rising trends of anthropogenic <span class="hlt">aerosol</span> emissions. In this study, the spatio-temporal <span class="hlt">aerosol</span> distributions over South Asia from seven global <span class="hlt">aerosol</span> models are evaluated against <span class="hlt">aerosol</span> retrievals from NASA satellite sensors and ground-based measurements for the period of 2000-2007. Overall, substantial underestimations of <span class="hlt">aerosol</span> loading over South Asia are found systematically in most model simulations. Averaged over the entire South Asia, the annual mean <span class="hlt">aerosol</span> optical depth (AOD) is underestimated by a range 15 to 44% across models compared to MISR (Multi-angle <span class="hlt">Imaging</span> SpectroRadiometer), which is the lowest bound among various satellite AOD retrievals (from MISR, SeaWiFS (Sea-Viewing Wide Field-of-View Sensor), MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) Aqua and Terra). In particular during the post-monsoon and wintertime periods (i.e., October-January), when agricultural waste burning and anthropogenic emissions dominate, models fail to capture AOD and <span class="hlt">aerosol</span> absorption optical depth (AAOD) over the Indo-Gangetic Plain (IGP) compared to ground-based <span class="hlt">Aerosol</span> Robotic Network (AERONET) sunphotometer measurements. The underestimations of <span class="hlt">aerosol</span> loading in models generally occur in the lower troposphere (below 2 km) based on the comparisons of <span class="hlt">aerosol</span> extinction profiles calculated by the models with those from Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization (CALIOP) data. Furthermore, surface concentrations of all <span class="hlt">aerosol</span> components (sulfate, nitrate, organic <span class="hlt">aerosol</span> (OA) and black carbon (BC)) from the models are found much lower than in situ measurements in winter. Several possible causes for these common problems of underestimating <span class="hlt">aerosols</span> in models during the post-monsoon and wintertime periods are identified: the <span class="hlt">aerosol</span> hygroscopic growth and formation of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=169768','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=169768"><span id="translatedtitle">Bedding disposal cabinet for containment of <span class="hlt">aerosols</span> generated by animal cage cleaning procedures.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Baldwin, C L; Sabel, F L; Henke, C B</p> <p>1976-01-01</p> <p>Laboratory tests with <span class="hlt">aerosolized</span> spores and animal room tests with uranine dye indicate the effectiveness of a prototype bedding disposal cabinet in reducing airborne contamination generated by cage cleaning procedures. <span class="hlt">Images</span> PMID:826219</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980018611','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980018611"><span id="translatedtitle">First Estimates of the Radiative Forcing of <span class="hlt">Aerosols</span> Generated from Biomass Burning using Satellite Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chistopher, Sundar A.; Kliche, Donna V.; Chou, Joyce; Welch, Ronald M.</p> <p>1996-01-01</p> <p>Collocated measurements from the Advanced Very High Resolution Radiometer (AVHRR) and the Earth Radiation Budget Experiment (ERBE) scanner are used to examine the radiative forcing of atmospheric <span class="hlt">aerosols</span> generated from biomass burning for 13 <span class="hlt">images</span> in South America. Using the AVHRR, Local Area Coverage (LAC) data, a new technique based on a combination of spectral and textural measures is developed for detecting these <span class="hlt">aerosols</span>. Then, the instantaneous shortwave, longwave, and net radiative forcing values are computed from the ERBE instantaneous scanner data. Results for the selected samples from 13 <span class="hlt">images</span> show that the mean instantaneous net radiative forcing for areas with heavy <span class="hlt">aerosol</span> loading is about -36 W/sq m and that for the optically thin <span class="hlt">aerosols</span> are about -16 W/sq m. These results, although preliminary, provide the first estimates of radiative forcing of atmospheric <span class="hlt">aerosols</span> from biomass burning using satellite data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970020060','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970020060"><span id="translatedtitle">First Estimates of the Radiative Forcing of <span class="hlt">Aerosols</span> Generated from Biomass Burning Using Satellite Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Christopher, Sundar A.; Kliche, Donna A.; Chou, Joyce; Welch, Ronald M.</p> <p>1996-01-01</p> <p>Collocated measurements from the Advanced Very High Resolution Radiometer (AVHRR) and the Earth Radiation Budget Experiment (ERBE) scanner are used to examine the radiative forcing of atmospheric <span class="hlt">aerosols</span> generated from biomass burning for 13 <span class="hlt">images</span> in South America. Using the AVHRR, Local Area Coverage (LAC) data, a new technique based on a combination of spectral and textural measures is developed for detecting these <span class="hlt">aerosols</span>. Then, the instantaneous shortwave, longwave, and net radiative forcing values are computed from the ERBE instantaneous scanner data. Results for the selected samples from 13 <span class="hlt">images</span> show that the mean instantaneous net radiative forcing for areas with heavy <span class="hlt">aerosol</span> loading is about -36 W/sq m and that for the optically thin <span class="hlt">aerosols</span> are about -16 W/sq m. These results, although preliminary, provide the first estimates of radiative forcing of atmospheric <span class="hlt">aerosols</span> from biomass burning using satellite data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030067938','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030067938"><span id="translatedtitle">Longwave Radiative Forcing of Saharan Dust <span class="hlt">Aerosols</span> Estimated from MODIS, MISR and CERES Observations on Terra</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhang, Jiang-Long; Christopher, Sundar A.</p> <p>2003-01-01</p> <p>Using observations from the Multi-angle <span class="hlt">Imaging</span> Spectroradiometer (MISR), the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), and the Clouds and the Earth's Radiant Energy System (CERES) instruments onboard the Terra satellite; we present a new technique for studying longwave (LW) radiative forcing of dust <span class="hlt">aerosols</span> over the Saharan desert for cloud-free conditions. The monthly-mean LW forcing for September 2000 is 7 W/sq m and the LW forcing efficiency' (LW(sub eff)) is 15 W/sq m. Using radiative transfer calculations, we also show that the vertical distribution of <span class="hlt">aerosols</span> and water vapor are critical to the understanding of dust <span class="hlt">aerosol</span> forcing. Using well calibrated, spatially and temporally collocated data sets, we have combined the strengths of three sensors from the same satellite to quantify the LW radiative forcing, and show that dust <span class="hlt">aerosols</span> have a "warming" effect over the Saharan desert that will counteract the shortwave "cooling effect" of <span class="hlt">aerosols</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4126729','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4126729"><span id="translatedtitle">Exhaled <span class="hlt">Aerosol</span> Pattern Discloses Lung Structural Abnormality: A Sensitivity Study Using Computational Modeling and Fractal Analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xi, Jinxiang; Si, Xiuhua A.; Kim, JongWon; Mckee, Edward; Lin, En-Bing</p> <p>2014-01-01</p> <p>Background Exhaled <span class="hlt">aerosol</span> patterns, also called <span class="hlt">aerosol</span> fingerprints, provide clues to the health of the lung and can be used to detect disease-modified airway structures. The key is how to decode the exhaled <span class="hlt">aerosol</span> fingerprints and retrieve the lung structural information for a non-invasive identification of respiratory diseases. Objective and Methods In this study, a CFD-fractal analysis method was developed to quantify exhaled <span class="hlt">aerosol</span> fingerprints and applied it to one benign and three malign conditions: a tracheal carina tumor, a bronchial tumor, and asthma. Respirations of tracer <span class="hlt">aerosols</span> of 1 µm at a flow rate of 30 L/min were simulated, with exhaled distributions recorded at the mouth. Large eddy simulations and a Lagrangian tracking approach were used to simulate respiratory airflows and <span class="hlt">aerosol</span> dynamics. <span class="hlt">Aerosol</span> morphometric measures such as concentration disparity, spatial distributions, and fractal analysis were applied to distinguish various exhaled <span class="hlt">aerosol</span> patterns. Findings Utilizing physiology-based modeling, we demonstrated substantial differences in exhaled <span class="hlt">aerosol</span> distributions among normal and pathological airways, which were suggestive of the disease location and extent. With fractal analysis, we also demonstrated that exhaled <span class="hlt">aerosol</span> patterns exhibited fractal behavior in both the entire <span class="hlt">image</span> and selected regions of interest. Each exhaled <span class="hlt">aerosol</span> fingerprint exhibited distinct pattern parameters such as spatial probability, fractal dimension, lacunarity, and multifractal spectrum. Furthermore, a correlation of the diseased location and exhaled <span class="hlt">aerosol</span> spatial distribution was established for asthma. Conclusion <span class="hlt">Aerosol</span>-fingerprint-based breath tests disclose clues about the site and severity of lung diseases and appear to be sensitive enough to be a practical tool for diagnosis and prognosis of respiratory diseases with structural abnormalities. PMID:25105680</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010017159','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010017159"><span id="translatedtitle">How Well Will MODIS Measure Top of Atmosphere <span class="hlt">Aerosol</span> Direct Radiative Forcing?</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Remer, Lorraine A.; Kaufman, Yoram J.; Levin, Zev; Ghan, Stephen; Einaudi, Franco (Technical Monitor)</p> <p>2000-01-01</p> <p>The new generation of satellite sensors such as the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) will be able to detect and characterize global <span class="hlt">aerosols</span> with an unprecedented accuracy. The question remains whether this accuracy will be sufficient to narrow the uncertainties in our estimates of <span class="hlt">aerosol</span> radiative forcing at the top of the atmosphere. Satellite remote sensing detects <span class="hlt">aerosol</span> optical thickness with the least amount of relative error when <span class="hlt">aerosol</span> loading is high. Satellites are less effective when <span class="hlt">aerosol</span> loading is low. We use the monthly mean results of two global <span class="hlt">aerosol</span> transport models to simulate the spatial distribution of smoke <span class="hlt">aerosol</span> in the Southern Hemisphere during the tropical biomass burning season. This spatial distribution allows us to determine that 87-94% of the smoke <span class="hlt">aerosol</span> forcing at the top of the atmosphere occurs in grid squares with sufficient signal to noise ratio to be detectable from space. The uncertainty of quantifying the smoke <span class="hlt">aerosol</span> forcing in the Southern Hemisphere depends on the uncertainty introduced by errors in estimating the background <span class="hlt">aerosol</span>, errors resulting from uncertainties in surface properties and errors resulting from uncertainties in assumptions of <span class="hlt">aerosol</span> properties. These three errors combine to give overall uncertainties of 1.5 to 2.2 Wm-2 (21-56%) in determining the Southern Hemisphere smoke <span class="hlt">aerosol</span> forcing at the top of the atmosphere. The range of values depend on which estimate of MODIS retrieval uncertainty is used, either the theoretical calculation (upper bound) or the empirical estimate (lower bound). Strategies that use the satellite data to derive flux directly or use the data in conjunction with ground-based remote sensing and <span class="hlt">aerosol</span> transport models can reduce these uncertainties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999GBioC..13..383S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999GBioC..13..383S"><span id="translatedtitle">Global distribution of <span class="hlt">aerosols</span> over the open ocean as derived from the Coastal Zone Color Scanner</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stegmann, P. M.; Tindale, N. W.</p> <p>1999-06-01</p> <p>Climatological maps of monthly mean <span class="hlt">aerosol</span> radiance levels derived from the coastal zone color scanner (CZCS) were constructed for the world's ocean basins. This is the first study to use the 7.5-year CZCS data set to examine the distribution and seasonality of <span class="hlt">aerosols</span> over the open ocean on a global scale. Examination of our satellite <span class="hlt">images</span> found the most prominent large-scale patch of elevated <span class="hlt">aerosol</span> radiances in each month off the coast of northwest Africa. The well-known, large-scale plumes of elevated <span class="hlt">aerosol</span> levels in the Arabian Sea, the northwest Pacific, and off the east coast of North America were also successfully captured. Radiance data were extracted from 13 major open-ocean zones, ranging from the subpolar to equatorial regions. Results from these extractions revealed the <span class="hlt">aerosol</span> load in both subpolar and subtropical zones to be higher in the Northern Hemisphere than in the Southern Hemisphere. <span class="hlt">Aerosol</span> radiances in the subtropics of both hemispheres were about 2 times higher in summer than in winter. In subpolar regions, <span class="hlt">aerosol</span> radiances in late spring/early summer were almost 3 times that observed in winter. In general, the <span class="hlt">aerosol</span> signal was higher during the warmer months and lower during the cooler months, irrespective of location. A comparison between our mean monthly <span class="hlt">aerosol</span> radiance maps with mean monthly chlorophyll maps (also from CZCS) showed similar seasonality between <span class="hlt">aerosol</span> and chlorophyll levels in the subpolar zones of both hemispheres, i.e., high levels in summer, low levels in winter. In the subtropics of both hemispheres, however, chlorophyll levels were higher in winter months which coincided with a depressed <span class="hlt">aerosol</span> signal. Our results indicate that the near-IR channel on ocean color sensors can be used to successfully capture well-known, large-scale <span class="hlt">aerosol</span> plumes on a global scale and that future ocean color sensors may provide a platform for long-term synoptic studies of combined <span class="hlt">aerosol</span>-phytoplankton productivity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20000120582&hterms=zones+ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dzones%2Bocean','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20000120582&hterms=zones+ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dzones%2Bocean"><span id="translatedtitle">Global Distribution of <span class="hlt">Aerosols</span> Over the Open Ocean as Derived from the Coastal Zone Color Scanner</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stegmann, P. M.; Tindale, N. W.</p> <p>1999-01-01</p> <p>Climatological maps of monthly mean <span class="hlt">aerosol</span> radiance levels derived from the coastal zone color scanner (CZCS) were constructed for the world's ocean basins. This is the first study to use the 7.5.-year CZCS data set to examine the distribution and seasonality of <span class="hlt">aerosols</span> over the open ocean on a global scale. Examination of our satellite <span class="hlt">images</span> found the most prominent large-scale patch of elevated <span class="hlt">aerosol</span> radiances in each month off the coast of northwest Africa. The well-known, large-scale plumes of elevated <span class="hlt">aerosol</span> levels in the Arabian Sea, the northwest Pacific, and off the east coast of North America were also successfully captured. Radiance data were extracted from 13 major open-ocean zones, ranging from the subpolar to equatorial regions. Results from these extractions revealed the <span class="hlt">aerosol</span> load in both subpolar and subtropical zones to be higher in the Northern Hemisphere than in the Southern Hemisphere. <span class="hlt">Aerosol</span> radiances in the subtropics of both hemispheres were about 2 times higher in summer than in winter. In subpolar regions, <span class="hlt">aerosol</span> radiances in late spring/early summer were almost 3 times that observed in winter. In general, the <span class="hlt">aerosol</span> signal was higher during the warmer months and lower during the cooler months, irrespective of location. A comparison between our mean monthly <span class="hlt">aerosol</span> radiance maps with mean monthly chlorophyll maps (also from CZCS) showed similar seasonality between <span class="hlt">aerosol</span> and chlorophyll levels in the subpolar zones of both hemispheres, i.e., high levels in summer, low levels in winter. In the subtropics of both hemispheres, however, chlorophyll levels were higher in winter months which coincided with a depressed <span class="hlt">aerosol</span> signal. Our results indicate that the near-IR channel on ocean color sensors can be used to successfully capture well-known, large-scale <span class="hlt">aerosol</span> plumes on a global scale and that future ocean color sensors may provide a platform for long-term synoptic studies of combined <span class="hlt">aerosol</span>-phytoplankton productivity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmEn.135...84C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmEn.135...84C"><span id="translatedtitle">Graphical <span class="hlt">aerosol</span> classification method using <span class="hlt">aerosol</span> relative optical depth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Qi-Xiang; Yuan, Yuan; Shuai, Yong; Tan, He-Ping</p> <p>2016-06-01</p> <p>A simple graphical method is presented to classify <span class="hlt">aerosol</span> types based on a combination of <span class="hlt">aerosol</span> optical thickness (AOT) and <span class="hlt">aerosol</span> relative optical thickness (AROT). Six <span class="hlt">aerosol</span> types, including maritime (MA), desert dust (DD), continental (CO), sub-continental (SC), urban industry (UI) and biomass burning (BB), are discriminated in a two dimensional space of AOT440 and AROT1020/440. Numerical calculations are performed using MIE theory based on a multi log-normal particle size distribution, and the AROT ranges for each <span class="hlt">aerosol</span> type are determined. More than 5 years of daily observations from 8 representative <span class="hlt">aerosol</span> sites are applied to the method to confirm spatial applicability. Finally, 3 individual cases are analyzed according to their specific <span class="hlt">aerosol</span> status. The outcomes indicate that the new graphical method coordinates well with regional characteristics and is also able to distinguish <span class="hlt">aerosol</span> variations in individual situations. This technique demonstrates a novel way to estimate different <span class="hlt">aerosol</span> types and provide information on radiative forcing calculations and satellite data corrections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/2707210','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/2707210"><span id="translatedtitle">Exposures to acidic <span class="hlt">aerosols</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Spengler, J D; Keeler, G J; Koutrakis, P; Ryan, P B; Raizenne, M; Franklin, C A</p> <p>1989-02-01</p> <p>Ambient monitoring of acid <span class="hlt">aerosols</span> in four U.S. cities and in a rural region of southern Ontario clearly show distinct periods of strong acidity. Measurements made in Kingston, TN, and Steubenville, OH, resulted in 24-hr H+ ion concentrations exceeding 100 nmole/m3 more than 10 times during summer months. Periods of elevated acidic <span class="hlt">aerosols</span> occur less frequently in winter months. The H+ determined during episodic conditions in southern Ontario indicates that respiratory tract deposition can exceed the effects level reported in clinical studies. Observed 12-hr H+ concentrations exceeded 550 nmole/m3 (approximately 27 micrograms/m3 H2SO4). The maximum estimated 1-hr concentration exceeded 1500 nmole/m3 for H+ ions. At these concentrations, an active child might receive more than 2000 nmole of H+ ion in 12 hr and in excess of 900 nmole during the hour when H2SO4 exceeded 50 micrograms/m3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1020729','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1020729"><span id="translatedtitle"><span class="hlt">Aerosol</span> Observing System (AOS) Handbook</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jefferson, A</p> <p>2011-01-17</p> <p>The <span class="hlt">Aerosol</span> Observing System (AOS) is a suite of in situ surface measurements of <span class="hlt">aerosol</span> optical and cloud-forming properties. The instruments measure <span class="hlt">aerosol</span> properties that influence the earth’s radiative balance. The primary optical measurements are those of the <span class="hlt">aerosol</span> scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. <span class="hlt">Aerosol</span> optical measurements are useful for calculating parameters used in radiative forcing calculations such as the <span class="hlt">aerosol</span> single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AtmEn..83...43Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AtmEn..83...43Z"><span id="translatedtitle">Optical properties and radiative forcing of urban <span class="hlt">aerosols</span> in Nanjing, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhuang, B. L.; Wang, T. J.; Li, S.; Liu, J.; Talbot, R.; Mao, H. T.; Yang, X. Q.; Fu, C. B.; Yin, C. Q.; Zhu, J. L.; Che, H. Z.; Zhang, X. Y.</p> <p>2014-02-01</p> <p>Continuous measurements of atmospheric <span class="hlt">aerosols</span> were made in Nanjing, a megacity in China, from 18 January to 18 April, 2011 (Phase 1) and from 22 April 2011 to 21 April 2012 (Phase 2). <span class="hlt">Aerosol</span> characteristics, optical properties, and direct radiative forcing (DRF) were studied through interpretations of these measurements. We found that during Phase 1, mean PM2.5, black carbon (BC), and <span class="hlt">aerosol</span> scattering coefficient (Bsp) in Nanjing were 76.1 ± 59.3 μg m-3, 4.1 ± 2.2 μg m-3, and 170.9 ± 105.8 M m-1, respectively. High pollution episodes occurred during Spring and Lantern Festivals when hourly PM2.5 concentrations reached 440 μg m-3, possibly due to significant discharge of fireworks. Temporal variations of PM2.5, BC, and Bsp were similar to each other. It is estimated that inorganic scattering <span class="hlt">aerosols</span> account for about 49 ± 8.6% of total <span class="hlt">aerosols</span> while BC only accounted for 6.6 ± 2.9%, and nitrate was larger than sulfate. In Phase 2, optical properties of <span class="hlt">aerosols</span> show great seasonality. High relative humidity (RH) in summer (June, July, August) likely attributed to large optical depth (AOD) and small Angstrom exponent (AE) of <span class="hlt">aerosols</span>. Due to dust storms, AE of total <span class="hlt">aerosols</span> was the smallest in spring (March, April, May). Annual mean 550-nm AOD and 675/440-nm AE were 0.6 ± 0.3 and 1.25 ± 0.29 for total <span class="hlt">aerosols</span>, 0.04 ± 0.02 and 1.44 ± 0.50 for absorbing <span class="hlt">aerosols</span>, 0.48 ± 0.29 and 1.64 ± 0.29 for fine <span class="hlt">aerosols</span>, respectively. Annual single scattering albedo of <span class="hlt">aerosols</span> ranged from 0.90 to 0.92. Real time wavelength-dependent surface albedo from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) was used to assess <span class="hlt">aerosol</span> DRFs. Both total and absorbing <span class="hlt">aerosol</span> DRFs had significant seasonal variations in Nanjing and they were the strongest in summer. Annual mean clear sky TOA DRF (including daytime and nighttime) of total and absorbing <span class="hlt">aerosols</span> was about -6.9 and +4.5 W m-2, respectively. <span class="hlt">Aerosol</span> DRFs were found to be sensitive to surface</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999SPIE.3533...43D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999SPIE.3533...43D"><span id="translatedtitle">Biological <span class="hlt">aerosol</span> trigger</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DeSha, Michael S.</p> <p>1999-01-01</p> <p>In recent history, manmade and natural events have shown us the every-present need for systems to monitor the troposphere for contaminates. These contaminants may take either a chemical or biological form, which determines the methods we use to monitor them. Monitoring the troposphere for biological contaminants is of particular interest to my organization. Whether manmade or natural, contaminants of a biological origin share similar constituents; typically the aromatic amino acids tryptophan, phenylalanine, and tyrosine. All of these proteinaceous compounds autofluorescence when exposed to UV radiation and this established the basis of the laser-induced fluorescence technique we use to detect biological contaminants. This technique can be employed in either point or remote detection schemes and is a valuable tool for discriminating proteinaceous form non-proteinaceous <span class="hlt">aerosols</span>. For this particular presentation I am going to describe a breadboard point sensor we designed and fabricated to detect proteinaceous <span class="hlt">aerosols</span>. Previous point sensor designs relied on convoluted flow paths to concentrate the <span class="hlt">aerosols</span> into a solution. Other systems required precise beam alignment to evenly distribute the energy irradiating the detector elements. Our objective was to build a simple system where beam alignment is not critical, and the flow is straight and laminar. The breadboard system was developed over a nine- month period and its performance assessed at a recent test at Dugway Proving Grounds in Utah. In addition, we have performed chamber experiments in an attempt to establish a baseline for the systems. The results of these efforts are presented here.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1230771-cantera-aerosol-dynamics-simulator','SCIGOV-ESTSC'); return false;" href="http://www.osti.gov/scitech/biblio/1230771-cantera-aerosol-dynamics-simulator"><span id="translatedtitle">Cantera <span class="hlt">Aerosol</span> Dynamics Simulator</span></a></p> <p><a target="_blank" href=""></a></p> <p></p> <p>2004-09-01</p> <p>The Cantera <span class="hlt">Aerosol</span> Dynamics Simulator (CADS) package is a general library for <span class="hlt">aerosol</span> modeling to address <span class="hlt">aerosol</span> general dynamics, including formation from gas phase reactions, surface chemistry (growth and oxidation), bulk particle chemistry, transport by Brownian diffusion, thermophoresis, and diffusiophoresis with linkage to DSMC studies, and thermal radiative transport. The library is based upon Cantera, a C++ Cal Tech code that handles gas phase species transport, reaction, and thermodynamics. The method uses a discontinuous galerkinmore » formulation for the condensation and coagulation operator that conserves particles, elements, and enthalpy up to round-off error. Both O-D and 1-D time dependent applications have been developed with the library. Multiple species in the solid phase are handled as well. The O-D application, called Tdcads (Time Dependent CADS) is distributed with the library. Tdcads can address both constant volume and constant pressure adiabatic homogeneous problems. An extensive set of sample problems for Tdcads is also provided.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770008620','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770008620"><span id="translatedtitle">Atmospheric <span class="hlt">aerosols</span>: Their Optical Properties and Effects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1976-01-01</p> <p>Measured properties of atmospheric <span class="hlt">aerosol</span> particles are presented. These include <span class="hlt">aerosol</span> size frequency distribution and complex retractive index. The optical properties of <span class="hlt">aerosols</span> are computed based on the presuppositions of thermodynamic equilibrium and of Mie-theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17776243','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17776243"><span id="translatedtitle">Volcanic <span class="hlt">aerosols</span> and lunar eclipses.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Keen, R A</p> <p>1983-12-01</p> <p>The moon is visible during total lunar eclipses due to sunlight refracted into the earth's shadow by the atmosphere. Stratospheric <span class="hlt">aerosols</span> can profoundly affect the brightness of the eclipsed moon. Observed brightnesses of 21 lunar eclipses during 1960-1982 are compared with theoretical calculations based on refraction by an <span class="hlt">aerosol</span>-free atmosphere to yield globally averaged <span class="hlt">aerosol</span> optical depths. Results indicate the global <span class="hlt">aerosol</span> loading from the 1982 eruption of El Chichón is similar in magnitude to that from the 1963 Agung eruption.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/17776243','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/17776243"><span id="translatedtitle">Volcanic <span class="hlt">aerosols</span> and lunar eclipses.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Keen, R A</p> <p>1983-12-01</p> <p>The moon is visible during total lunar eclipses due to sunlight refracted into the earth's shadow by the atmosphere. Stratospheric <span class="hlt">aerosols</span> can profoundly affect the brightness of the eclipsed moon. Observed brightnesses of 21 lunar eclipses during 1960-1982 are compared with theoretical calculations based on refraction by an <span class="hlt">aerosol</span>-free atmosphere to yield globally averaged <span class="hlt">aerosol</span> optical depths. Results indicate the global <span class="hlt">aerosol</span> loading from the 1982 eruption of El Chichón is similar in magnitude to that from the 1963 Agung eruption. PMID:17776243</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19790031093&hterms=climatic+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dclimatic%2Bchange','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19790031093&hterms=climatic+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dclimatic%2Bchange"><span id="translatedtitle">Stratospheric <span class="hlt">aerosols</span> and climatic change</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Toon, O. B.; Pollack, J. B.</p> <p>1978-01-01</p> <p>Stratospht1ic sulfuric acid particles scatter and absorb sunlight and they scatter, absorb and emit terrestrial thermal radiation. These interactions play a role in the earth's radiation balance and therefore affect climate. The stratospheric <span class="hlt">aerosols</span> are perturbed by volcanic injection of SO2 and ash, by aircraft injection of SO2, by rocket exhaust of Al2O3 and by tropospheric mixing of particles and pollutant SO2 and COS. In order to assess the effects of these perturbations on climate, the effects of the <span class="hlt">aerosols</span> on the radiation balance must be understood and in order to understand the radiation effects the properties of the <span class="hlt">aerosols</span> must be known. The discussion covers the <span class="hlt">aerosols</span>' effect on the radiation balance. It is shown that the <span class="hlt">aerosol</span> size distribution controls whether the <span class="hlt">aerosols</span> will tend to warm or cool the earth's surface. Calculations of <span class="hlt">aerosol</span> properties, including size distribution, for various perturbation sources are carried out on the basis of an <span class="hlt">aerosol</span> model. Calculations are also presented of the climatic impact of perturbed <span class="hlt">aerosols</span> due to volcanic eruptions and Space Shuttle flights.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Cinnamon&id=ED229789','ERIC'); return false;" href="http://eric.ed.gov/?q=Cinnamon&id=ED229789"><span id="translatedtitle"><span class="hlt">CAI</span> Invention Strategies.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Rodrigues, Raymond J.; Rodrigues, Dawn</p> <p></p> <p>Prewriting programs using computers fall into two broad categories: interactive and noninteractive. An early example of a noninteractive program is that of Ellen Nold, called "Cinnamon." Its purpose was to present the student with a series of content questions. In answering such questions, the student would be accumulating a set of data that could…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=cathode+AND+ray+AND+tube&pg=2&id=EJ020346','ERIC'); return false;" href="http://eric.ed.gov/?q=cathode+AND+ray+AND+tube&pg=2&id=EJ020346"><span id="translatedtitle"><span class="hlt">CAI</span> Physics Experiments</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Lindsay, Robert E.</p> <p>1970-01-01</p> <p>Describes a novel instructional method for physics involving the use of a computer assisted instruction system equipped with cathode-ray-tube terminals, light pen, and keyboard input. Discusses exercises with regard to content, mediation, scoring and control. Several examples of exercises are given along with results from student evaluation. (LC)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AMTD....7.8945L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AMTD....7.8945L"><span id="translatedtitle">Improving satellite retrieved <span class="hlt">aerosol</span> microphysical properties using GOCART data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, S.; Kahn, R.; Chin, M.; Garay, M. J.; Chen, L.; Liu, Y.</p> <p>2014-09-01</p> <p>The Multi-Angle <span class="hlt">Imaging</span> Spectro-Radiometer (MISR) instrument on NASA's Terra satellite can provide more reliable <span class="hlt">Aerosol</span> Optical Depth (AOD, τ) and more particle information, such as constraints on particle size (Angström exponent or ANG, α), particle shape, and single-scattering albedo (SSA, ω), than many other satellite instruments. However, MISR's ability to retrieve <span class="hlt">aerosol</span> properties is weakened at low AOD levels. When <span class="hlt">aerosol</span>-type information content is low, many candidate <span class="hlt">aerosol</span> mixtures can match the observed radiances. We propose an algorithm to improve MISR <span class="hlt">aerosol</span> retrievals by constraining MISR mixtures' ANG and absorbing AOD (AAOD) with Goddard Chemistry <span class="hlt">Aerosol</span> Radiation and Transport (GOCART) model-simulated <span class="hlt">aerosol</span> properties. To demonstrate this approach, we calculated MISR <span class="hlt">aerosol</span> optical properties over the contiguous US from 2006 to 2009. Sensitivities associated with the thresholds of MISR-GOCART differences were analyzed according to the agreement between our results (AOD, ANG, and AAOD) and <span class="hlt">AErosol</span> RObotic NETwork (AERONET) observations. Overall, our AOD has a good agreement with AERONET because the MISR AOD retrieval is not sensitive to different mixtures under many retrieval conditions. The correlation coefficient (r) between our ANG and AERONET improves to 0.45 from 0.29 for the MISR Version 22 standard product and 0.43 for GOCART when all data points are included. However, when only cases having AOD > 0.2, the MISR product itself has r ~ 0.40, and when only AOD > 0.2 and the best-fitting mixture are considered, r ~ 0.49. So as expected, the ANG improvement occurs primarily when the model constraint is applied in cases where the particle type information content of the MISR radiances is low. Regression analysis for AAOD shows that MISR Version 22 and GOCART misestimate AERONET by a ratio (mean retrieved AAOD to mean AERONET AAOD) of 0.5; our method improves this ratio to 0.74. Large discrepancies are found through an inter</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20150007827&hterms=3d+camera&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D3d%2Bcamera','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20150007827&hterms=3d+camera&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3D3d%2Bcamera"><span id="translatedtitle">3D Radiative Transfer Effects in Multi-Angle/Multi-Spectral Radio-Polarimetric Signals from a Mixture of Clouds and <span class="hlt">Aerosols</span> Viewed by a Non-<span class="hlt">Imaging</span> Sensor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Davis, Anthony B.; Garay, Michael J.; Xu, Feng; Qu, Zheng; Emde, Claudia</p> <p>2013-01-01</p> <p>When observing a spatially complex mix of <span class="hlt">aerosols</span> and clouds in a single relatively large field-of-view, nature entangles their signals non-linearly through polarized radiation transport processes that unfold in the 3D position and direction spaces. In contrast, any practical forward model in a retrieval algorithm will use only 1D vector radiative transfer (vRT) in a linear mixing technique. We assess the difference between the observed and predicted signals using synthetic data from a high-fidelity 3D vRT model with clouds generated using a Large Eddy Simulation model and an <span class="hlt">aerosol</span> climatology. We find that this difference is signal--not noise--for the <span class="hlt">Aerosol</span> Polarimetry Sensor (APS), an instrument developed by NASA. Moreover, the worst case scenario is also the most interesting case, namely, when the <span class="hlt">aerosol</span> burden is large, hence hase the most impact on the cloud microphysics and dynamics. Based on our findings, we formulate a mitigation strategy for these unresolved cloud adjacency effects assuming that some spatial information is available about the structure of the clouds at higher resolution from "context" cameras, as was planned for NASA's ill-fated Glory mission that was to carry the APS but failed to reach orbit. Application to POLDER (POLarization and Directionality of Earth Reflectances) data from the period when PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) was in the A-train is briefly discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A51A0001K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A51A0001K"><span id="translatedtitle">Developments of <span class="hlt">aerosol</span> retrieval algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS) and the retrieval accuracy test</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>KIM, M.; Kim, J.; Jeong, U.; Ahn, C.; Bhartia, P. K.; Torres, O.</p> <p>2013-12-01</p> <p>A scanning UV-Visible spectrometer, the GEMS (Geostationary Environment Monitoring Spectrometer) onboard the GEO-KOMPSAT2B (Geostationary Korea Multi-Purpose Satellite) is planned to be launched in geostationary orbit in 2018. The GEMS employs hyper-spectral <span class="hlt">imaging</span> with 0.6 nm resolution to observe solar backscatter radiation in the UV and Visible range. In the UV range, the low surface contribution to the backscattered radiation and strong interaction between <span class="hlt">aerosol</span> absorption and molecular scattering can be advantageous in retrieving <span class="hlt">aerosol</span> optical properties such as <span class="hlt">aerosol</span> optical depth (AOD) and single scattering albedo (SSA). By taking the advantage, the OMI UV <span class="hlt">aerosol</span> algorithm has provided information on the absorbing <span class="hlt">aerosol</span> (Torres et al., 2007; Ahn et al., 2008). This study presents a UV-VIS algorithm to retrieve AOD and SSA from GEMS. The algorithm is based on the general inversion method, which uses pre-calculated look-up table with assumed <span class="hlt">aerosol</span> properties and measurement condition. To obtain the retrieval accuracy, the error of the look-up table method occurred by the interpolation of pre-calculated radiances is estimated by using the reference dataset, and the uncertainties about <span class="hlt">aerosol</span> type and height are evaluated. Also, the GEMS <span class="hlt">aerosol</span> algorithm is tested with measured normalized radiance from OMI, a provisional data set for GEMS measurement, and the results are compared with the values from AERONET measurements over Asia. Additionally, the method for simultaneous retrieve of the AOD and <span class="hlt">aerosol</span> height is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015EGUGA..1714619S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2015EGUGA..1714619S&link_type=ABSTRACT"><span id="translatedtitle">Spatial and Temporal Monitoring of <span class="hlt">Aerosol</span> over Selected Urban Areas in Egypt</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shokr, Mohammed; El-Tahan, Mohammed; Ibrahim, Alaa</p> <p>2015-04-01</p> <p>We utilize remote sensing data of atmospheric <span class="hlt">aerosols</span> from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) aboard the Terra and Aqua satellites to explore spatio-temporal patterns over selected urban sites in Egypt during 2000-2015. High resolution (10 x 10 km^2) Level 2, collection 5, quality-controlled product was used. The selected sites are characterized by different human and industrial activities as well as landscape and meteorological attributes. These have impacts on the dominant types and intensity of <span class="hlt">aerosols</span>. <span class="hlt">Aerosol</span> robotic network (AERONET) data were used to validate the calculations from MODIS. The suitability of the MODIS product in terms of spatial and temporal coverage as well as accuracy and robustness has been established. Seasonal patterns of <span class="hlt">aerosol</span> concentration are identified and compared between the sites. Spatial gradient of <span class="hlt">aerosol</span> is assessed in the vicinity of major <span class="hlt">aerosol</span>-emission sites (e.g. Cairo) to determine the range of influence of the generated pollution. Peak <span class="hlt">aerosol</span> concentrations are explained in terms of meteorological events and land cover. The limited trends found in the temporal records of the <span class="hlt">aerosol</span> measurements will be confirmed using calibrated long-term ground observations. The study has been conducted under the PEER 2-239 research project titled "The Impact of Biogenic and Anthropogenic Atmospheric <span class="hlt">Aerosols</span> to Climate in Egypt". Project website is CleanAirEgypt.org</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRD..121.6459Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRD..121.6459Y"><span id="translatedtitle">Distinct impact of different types of <span class="hlt">aerosols</span> on surface solar radiation in China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Xin; Zhao, Chuanfeng; Zhou, Lijing; Wang, Yang; Liu, Xiaohong</p> <p>2016-06-01</p> <p>Observations of surface direct solar radiation (DSR) and visibility, particulate matter with aerodynamic diameters less than 2.5 µm (PM2.5), together with the <span class="hlt">aerosol</span> optical thickness (AOT) taken from Moderate-Resolution <span class="hlt">Imaging</span> Spectroradiometer and Multiangle <span class="hlt">Imaging</span> Spectroradiometer, were investigated to gain insight into the impact of <span class="hlt">aerosol</span> pollution on surface solar radiation in China. The surface DSR decreased during 2004-2014 compared with 1993~2003 over eastern China, but no clear reduction was observed in remote regions with cleaner air. Significant correlations of visibility, PM2.5, and regionally averaged AOT with the surface DSR over eastern China indicate that <span class="hlt">aerosol</span> pollution greatly affects the energy available at the surface. The net loss of surface solar radiation also reduces the surface ground temperature over eastern China. However, the slope of the linear variation of the radiation with respect to atmospheric visibility is distinctly different at different stations, implying that the main <span class="hlt">aerosol</span> type varies regionally. The largest slope value occurs at Zhengzhou and indicates that the <span class="hlt">aerosol</span> absorption in central China is the highest, and lower slope values suggest relatively weakly absorbing types of <span class="hlt">aerosols</span> at other locations. The spatial distribution of the linear slopes agrees well with the geographical distribution of the absorbing <span class="hlt">aerosols</span> derived from the Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observations and Ozone Monitoring Instrument over China. The regional correlation between a larger slope value and higher absorbance properties of <span class="hlt">aerosols</span> indicates that the net effects of <span class="hlt">aerosols</span> on the surface solar energy and corresponding climatic effects are dependent on both <span class="hlt">aerosol</span> amount and optical properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.8348P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.8348P"><span id="translatedtitle">Evolution of <span class="hlt">aerosol</span> loading in Santiago de Chile between 1997 and 2014</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pistone, Kristina; Gallardo, Laura</p> <p>2015-04-01</p> <p>While <span class="hlt">aerosols</span> produced by major cities are a significant component of anthropogenic climate forcing as well as an important factor in public health, many South American cities have not been a major focus of <span class="hlt">aerosol</span> studies due in part to relatively few long-term observations in the region. Here we present a synthesis of the available data for the emerging megacity of Santiago, Chile. We report new results from a recent NASA AERONET (<span class="hlt">AErosol</span> RObotic NETwork) site in the Santiago basin, combining these with previous AERONET observations in Santiago as well as with a new assessment of the 11-station air quality monitoring network currently administered by the Chilean Environment Ministry (MMA, Ministerio del Medio Ambiente) to assess changes in <span class="hlt">aerosol</span> composition since 1997. While the average surface concentration of pollution components (specifically PM2.5 and PM10) has decreased, no significant change in total <span class="hlt">aerosol</span> optical depth was observed. However, changes in <span class="hlt">aerosol</span> size and composition are suggested by the proxy measurements. Previous studies have revealed limitations in purely satellite-based studies over Santiago due to biases from high surface reflection in the region, particularly in summer months (e.g. Escribano et al 2014). To overcome this difficulty and certain limitations in the air quality data, we next incorporate analysis of <span class="hlt">aerosol</span> products from the Multi-angle <span class="hlt">Imaging</span> SpectroRadiometer (MISR) instrument along with those from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) instrument, both on NASA's Terra satellite, to better quantify the high bias of MODIS. Thus incorporating these complementary datasets, we characterize the <span class="hlt">aerosol</span> over Santiago over the period 1997 to 2014, including the evolution of <span class="hlt">aerosol</span> properties over time and seasonal dependencies in the observed trends. References: Escribano et al (2014), "Satellite Retrievals of <span class="hlt">Aerosol</span> Optical Depth over a Subtropical Urban Area: The Role of Stratification and Surface</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AIPC.1531...31L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AIPC.1531...31L"><span id="translatedtitle">Growing up MODIS: Towards a mature <span class="hlt">aerosol</span> climate data record</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Levy, Robert C.</p> <p>2013-05-01</p> <p><span class="hlt">Aerosols</span> are major players within the Earth's climate system, affecting the radiation budget, clouds and the hydrological cycle. In high concentrations near the surface, <span class="hlt">aerosols</span> (or particulate matter, PM) affect visibility, impact air quality, and can contribute to poor health. Among others, Yoram Kaufman recognized the importance of <span class="hlt">aerosols</span> to climate, and helped to design new instrumentation and algorithms to retrieve and quantify global <span class="hlt">aerosol</span> properties. One instrument, known as the Moderate <span class="hlt">Imaging</span> Resolution Spectro-radiometer (MODIS), was deployed on the AM-1 satellite (later known as Terra), part of NASA's Earth Observing System (EOS). In 1998, armed with an M.S. and job experience in neither <span class="hlt">aerosols</span> nor satellites, I was looking for a new job. I somehow found my way to the MODIS <span class="hlt">Aerosol</span> team. It was only a year before Terra launch, and most major decisions about the MODIS <span class="hlt">aerosol</span> retrieval algorithms had been finalized. Since then, we worked through launch, initial evaluation of the product with AERONET and field deployments, and continued efforts to understand the product and refine retrieval algorithms. I have had opportunities to participate in field experiments, write papers, and earn my PhD. The "second generation" algorithm for <span class="hlt">aerosol</span> retrieval over land has been hugely successful. We have collected nearly a half-million collocations with AERONET and other dataseis, made new discoveries, and have contributed to research and operational projects globally. Due to the dedication of the entire team, the MODIS <span class="hlt">aerosol</span> product now is one of the highlights of NASA's EOS program. It is used for climate research and air quality forecasting, as well for applications not even considered before the MODIS era. More recently, a focus is on stitching the MODIS <span class="hlt">aerosol</span> product into the "climate data record" (CDR) for global <span class="hlt">aerosol</span>, determining whether the product has sufficient length, consistency and continuity to determine climate variability and change</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A21D3070K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A21D3070K"><span id="translatedtitle">Retrieval of <span class="hlt">Aerosol</span> information from UV measurement by using optimal estimation method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>KIM, M.; Kim, J.; Jeong, U.; Kim, W. V.; Kim, S. K.; Lee, S. D.; Moon, K. J.</p> <p>2014-12-01</p> <p>An algorithm to retrieve <span class="hlt">aerosol</span> optical depth (AOD), single scattering albedo (SSA), and <span class="hlt">aerosol</span> loading height is developed for GEMS (Geostationary Environment Monitoring Spectrometer) measurement. The GEMS is planned to be launched in geostationary orbit in 2018, and employs hyper-spectral <span class="hlt">imaging</span> with 0.6 nm resolution to observe solar backscatter radiation in the UV and Visible range. In the UV range, the low surface contribution to the backscattered radiation and strong interaction between <span class="hlt">aerosol</span> absorption and molecular scattering can be advantageous in retrieving <span class="hlt">aerosol</span> information such as AOD and SSA [Torres et al., 2007; Torres et al., 2013; Ahn et al., 2014]. However, the large contribution of atmospheric scattering results in the increase of the sensitivity of the backward radiance to <span class="hlt">aerosol</span> loading height. Thus, the assumption of <span class="hlt">aerosol</span> loading height becomes important issue to obtain accurate result. Accordingly, this study focused on the simultaneous retrieval of <span class="hlt">aerosol</span> loading height with AOD and SSA by utilizing the optimal estimation method. For the RTM simulation, the <span class="hlt">aerosol</span> optical properties were analyzed from AERONET inversion data (level 2.0) at 46 AERONET sites over ASIA. Also, 2-channel inversion method is applied to estimate a priori value of the <span class="hlt">aerosol</span> information to solve the Lavenberg Marquardt equation. The GEMS <span class="hlt">aerosol</span> algorithm is tested with OMI level-1B dataset, a provisional data for GEMS measurement, and the result is compared with OMI standard <span class="hlt">aerosol</span> product and AERONET values. The retrieved AOD and SSA show reasonable distribution compared with OMI products, and are well correlated with the value measured from AERONET. However, retrieval uncertainty in <span class="hlt">aerosol</span> loading height is relatively larger than other results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16076949','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16076949"><span id="translatedtitle">The effect of smoke, dust, and pollution <span class="hlt">aerosol</span> on shallow cloud development over the Atlantic Ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaufman, Yoram J; Koren, Ilan; Remer, Lorraine A; Rosenfeld, Daniel; Rudich, Yinon</p> <p>2005-08-01</p> <p>Clouds developing in a polluted environment tend to have more numerous but smaller droplets. This property may lead to suppression of precipitation and longer cloud lifetime. Absorption of incoming solar radiation by <span class="hlt">aerosols</span>, however, can reduce the cloud cover. The net <span class="hlt">aerosol</span> effect on clouds is currently the largest uncertainty in evaluating climate forcing. Using large statistics of 1-km resolution MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) satellite data, we study the <span class="hlt">aerosol</span> effect on shallow water clouds, separately in four regions of the Atlantic Ocean, for June through August 2002: marine <span class="hlt">aerosol</span> (30 degrees S-20 degrees S), smoke (20 degrees S-5 degrees N), mineral dust (5 degrees N-25 degrees N), and pollution <span class="hlt">aerosols</span> (30 degrees N- 60 degrees N). All four <span class="hlt">aerosol</span> types affect the cloud droplet size. We also find that the coverage of shallow clouds increases in all of the cases by 0.2-0.4 from clean to polluted, smoky, or dusty conditions. Covariability analysis with meteorological parameters associates most of this change to <span class="hlt">aerosol</span>, for each of the four regions and 3 months studied. In our opinion, there is low probability that the net <span class="hlt">aerosol</span> effect can be explained by coincidental, unresolved, changes in meteorological conditions that also accumulate <span class="hlt">aerosol</span>, or errors in the data, although further in situ measurements and model developments are needed to fully understand the processes. The radiative effect at the top of the atmosphere incurred by the <span class="hlt">aerosol</span> effect on the shallow clouds and solar radiation is -11 +/- 3 W/m2 for the 3 months studied; 2/3 of it is due to the <span class="hlt">aerosol</span>-induced cloud changes, and 1/3 is due to <span class="hlt">aerosol</span> direct radiative effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/16076949','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/16076949"><span id="translatedtitle">The effect of smoke, dust, and pollution <span class="hlt">aerosol</span> on shallow cloud development over the Atlantic Ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaufman, Yoram J; Koren, Ilan; Remer, Lorraine A; Rosenfeld, Daniel; Rudich, Yinon</p> <p>2005-08-01</p> <p>Clouds developing in a polluted environment tend to have more numerous but smaller droplets. This property may lead to suppression of precipitation and longer cloud lifetime. Absorption of incoming solar radiation by <span class="hlt">aerosols</span>, however, can reduce the cloud cover. The net <span class="hlt">aerosol</span> effect on clouds is currently the largest uncertainty in evaluating climate forcing. Using large statistics of 1-km resolution MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) satellite data, we study the <span class="hlt">aerosol</span> effect on shallow water clouds, separately in four regions of the Atlantic Ocean, for June through August 2002: marine <span class="hlt">aerosol</span> (30 degrees S-20 degrees S), smoke (20 degrees S-5 degrees N), mineral dust (5 degrees N-25 degrees N), and pollution <span class="hlt">aerosols</span> (30 degrees N- 60 degrees N). All four <span class="hlt">aerosol</span> types affect the cloud droplet size. We also find that the coverage of shallow clouds increases in all of the cases by 0.2-0.4 from clean to polluted, smoky, or dusty conditions. Covariability analysis with meteorological parameters associates most of this change to <span class="hlt">aerosol</span>, for each of the four regions and 3 months studied. In our opinion, there is low probability that the net <span class="hlt">aerosol</span> effect can be explained by coincidental, unresolved, changes in meteorological conditions that also accumulate <span class="hlt">aerosol</span>, or errors in the data, although further in situ measurements and model developments are needed to fully understand the processes. The radiative effect at the top of the atmosphere incurred by the <span class="hlt">aerosol</span> effect on the shallow clouds and solar radiation is -11 +/- 3 W/m2 for the 3 months studied; 2/3 of it is due to the <span class="hlt">aerosol</span>-induced cloud changes, and 1/3 is due to <span class="hlt">aerosol</span> direct radiative effect. PMID:16076949</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJMPB..2930003C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJMPB..2930003C"><span id="translatedtitle"><span class="hlt">Aerosol</span> synthesis and application of folded graphene-based materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Yantao; Wang, Zhongying; Qiu, Yang</p> <p>2015-12-01</p> <p>Graphene oxide colloid has been widely used in the synthesis of various graphene-based materials. Graphene oxide sheets, with a low bending rigidity, can be folded when assembled in aqueous phase. A simple but industrial scalable way, <span class="hlt">aerosol</span> processing, can be used to fabricate folded graphene-based materials. These folded materials can carry various cargo materials and be used in different applications such as time-controlled drug release, medical <span class="hlt">imaging</span> enhancement, catalyst support and energy related areas. The <span class="hlt">aerosol</span> synthesis of folded graphene-based materials can also be easily extended to fabricate hybrid nanomaterials without any complicated chemistries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=65916&keyword=understanding+AND+Reader&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78932969&CFTOKEN=27610184','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=65916&keyword=understanding+AND+Reader&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78932969&CFTOKEN=27610184"><span id="translatedtitle">INDOOR <span class="hlt">AEROSOLS</span> AND EXPOSURE ASSESSMENT</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This chapter provides an overview of both indoor <span class="hlt">aerosol</span> concentration measurements, and the considerations for assessment of exposure to <span class="hlt">aerosols</span> in non-occupational settings. The fixed-location measurements of concentration at an outdoor location, while commuting inside an a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900002762','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900002762"><span id="translatedtitle"><span class="hlt">Aerosol</span> in the Pacific troposphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Clarke, Antony D.</p> <p>1989-01-01</p> <p>The use of near real-time optical techniques is emphasized for the measurement of mid-tropospheric <span class="hlt">aerosol</span> over the Central Pacific. The primary focus is on measurement of the <span class="hlt">aerosol</span> size distribution over the range of particle diameters from 0.15 to 5.0 microns that are essential for modeling CO2 backscatter values in support of the laser atmospheric wind sounder (LAWS) program. The measurement system employs a LAS-X (Laser <span class="hlt">Aerosol</span> Spectrometer-PMS, Boulder, CO) with a custom 256 channel pulse height analyzer and software for detailed measurement and analysis of <span class="hlt">aerosol</span> size distributions. A thermal preheater system (Thermo Optic <span class="hlt">Aerosol</span> Descriminator (TOAD) conditions the <span class="hlt">aerosol</span> in a manner that allows the discrimination of the size distribution of individual <span class="hlt">aerosol</span> components such as sulfuric acid, sulfates and refractory species. This allows assessment of the relative contribution of each component to the BCO2 signal. This is necessary since the different components have different sources, exhibit independent variability and provide different BCO2 signals for a given mass and particle size. Field activities involve experiments designed to examine both temporal and spatial variability of these <span class="hlt">aerosol</span> components from ground based and aircraft platforms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19820061330&hterms=1092&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2526%25231092','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19820061330&hterms=1092&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3D%2526%25231092"><span id="translatedtitle">Mount Saint Helens <span class="hlt">aerosol</span> evolution</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Oberbeck, V. R.; Farlow, N. H.; Snetsinger, K. G.; Ferry, G. V.; Fong, W.; Hayes, D. M.</p> <p>1982-01-01</p> <p>Stratospheric <span class="hlt">aerosol</span> samples were collected using a wire impactor during the year following the eruption of Mt. St. Helens. Analysis of samples shows that <span class="hlt">aerosol</span> volume increased for 6 months due to gas-to-particle conversion and then decreased to background levels in the following 6 months.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011686','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011686"><span id="translatedtitle"><span class="hlt">Aerosol</span> Remote Sensing</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lenoble, Jacqueline (Editor); Remer, Lorraine (Editor); Tanre, Didier (Editor)</p> <p>2012-01-01</p> <p>This book gives a much needed explanation of the basic physical principles of radia5tive transfer and remote sensing, and presents all the instruments and retrieval algorithms in a homogenous manner. For the first time, an easy path from theory to practical algorithms is available in one easily accessible volume, making the connection between theoretical radiative transfer and individual practical solutions to retrieve <span class="hlt">aerosol</span> information from remote sensing. In addition, the specifics and intercomparison of all current and historical methods are explained and clarified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvL.106a5502R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvL.106a5502R"><span id="translatedtitle">Thermophoretically Dominated <span class="hlt">Aerosol</span> Coagulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosner, Daniel E.; Arias-Zugasti, Manuel</p> <p>2011-01-01</p> <p>A theory of <span class="hlt">aerosol</span> coagulation due to size-dependent thermophoresis is presented. This previously overlooked effect is important when local temperature gradients are large, the sol population is composed of particles of much greater thermal conductivity than the carrier gas, with mean diameters much greater than the prevailing gas mean free path, and an adequate “spread” in sizes (as in metallurgical mists or fumes). We illustrate this via a population-balance analysis of the evolution of an initially log-normal distribution when this mechanism dominates ordinary Brownian diffusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19980227623&hterms=scanning+lidar&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dscanning%2Blidar','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19980227623&hterms=scanning+lidar&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dscanning%2Blidar"><span id="translatedtitle">CART and GSFC raman lidar measurements of atmospheric <span class="hlt">aerosol</span> backscattering and extinction profiles for EOS validation and ARM radiation studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ferrare, R. A.; Turner, D. D.; Melfi, S. H.; Whiteman, D. N.; Schwenner, G.; Evans, K. D.; Goldsmith, J. E. M.; Tooman, T.</p> <p>1998-01-01</p> <p>The <span class="hlt">aerosol</span> retrieval algorithms used by the Moderate-Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) and Multi-Angle <span class="hlt">Imaging</span> SpectroRadiometer (MISR) sensors on the Earth Observing Satellite (EOS) AM-1 platform operate by comparing measured radiances with tabulated radiances that have been computed for specific <span class="hlt">aerosol</span> models. These <span class="hlt">aerosol</span> models are based almost entirely on surface and/or column averaged measurements and so may not accurately represent the ambient <span class="hlt">aerosol</span> properties. Therefore, to validate these EOS algorithms and to determine the effects of <span class="hlt">aerosols</span> on the clear-sky radiative flux, we have begun to evaluate the vertical variability of ambient <span class="hlt">aerosol</span> properties using the <span class="hlt">aerosol</span> backscattering and extinction profiles measured by the Cloud and Radiation Testbed (CART) and NASA Goddard Space Flight Center (GSFC) Raman Lidars. Using the procedures developed for the GSFC Scanning Raman Lidar (SRL), we have developed and have begun to implement algorithms for the CART Raman Lidar to routinely provide profiles of <span class="hlt">aerosol</span> extinction and backscattering during both nighttime and ,daytime operations. <span class="hlt">Aerosol</span> backscattering and extinction profiles are computed for both lidar systems using data acquired during the 1996 and 1997 Water Vapor Intensive Operating Periods (IOPs). By integrating these <span class="hlt">aerosol</span> extinction profiles, we derive measurements of <span class="hlt">aerosol</span> optical thickness and compare these with coincident sun photometer measurements. We also use these measurements to measure the <span class="hlt">aerosol</span> extinction/backscatter ratio S(sub a) (i.e. 'lidar ratio'). Furthermore, we use the simultaneous water vapor measurements acquired by these Raman lidars to investigate the effects of water vapor on <span class="hlt">aerosol</span> optical properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeCoA.189...70K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeCoA.189...70K"><span id="translatedtitle">A link between oxygen, calcium and titanium isotopes in 26Al-poor hibonite-rich <span class="hlt">CAIs</span> from Murchison and implications for the heterogeneity of dust reservoirs in the solar nebula</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kööp, Levke; Davis, Andrew M.; Nakashima, Daisuke; Park, Changkun; Krot, Alexander N.; Nagashima, Kazuhide; Tenner, Travis J.; Heck, Philipp R.; Kita, Noriko T.</p> <p>2016-09-01</p> <p>PLACs (platy hibonite crystals) and related hibonite-rich calcium-, aluminum-rich inclusions (<span class="hlt">CAIs</span>; hereafter collectively referred to as PLAC-like <span class="hlt">CAIs</span>) have the largest nucleosynthetic isotope anomalies of all materials believed to have formed in the solar system. Most PLAC-like <span class="hlt">CAIs</span> have low inferred initial 26Al/27Al ratios and could have formed prior to injection or widespread distribution of 26Al in the solar nebula. In this study, we report 26Al-26Mg systematics combined with oxygen, calcium, and titanium isotopic compositions for a large number of newly separated PLAC-like <span class="hlt">CAIs</span> from the Murchison CM2 chondrite (32 <span class="hlt">CAIs</span> studied for oxygen, 26 of these also for 26Al-26Mg, calcium and titanium). Our results confirm (1) the large range of nucleosynthetic anomalies in 50Ti and 48Ca (our data range from -70‰ to +170‰ and -60‰ to +80‰, respectively), (2) the substantial range of Δ17O values (-28‰ to -17‰, with Δ17O = δ17O - 0.52 × δ18O), and (3) general 26Al-depletion in PLAC-like <span class="hlt">CAIs</span>. The multielement approach reveals a relationship between Δ17O and the degree of variability in 50Ti and 48Ca: PLAC-like <span class="hlt">CAIs</span> with the highest Δ17O (∼-17‰) show large positive and negative 50Ti and 48Ca anomalies, while those with the lowest Δ17O (∼-28‰) have small to no anomalies in 50Ti and 48Ca. These observations could suggest a physical link between anomalous 48Ca and 50Ti carriers and an 16O-poor reservoir. We suggest that the solar nebula was isotopically heterogeneous shortly after collapse of the protosolar molecular cloud, and that the primordial dust reservoir, in which anomalous carrier phases were heterogeneously distributed, was 16O-poor (Δ17O ⩾ -17‰) relative to the primordial gaseous (CO + H2O) reservoir (Δ17O < -35‰). However, other models such as CO self-shielding in the protoplanetary disk are also considered to explain the link between oxygen and calcium and titanium isotopes in PLAC-like <span class="hlt">CAIs</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JGR...10515329D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JGR...10515329D"><span id="translatedtitle">Estimate of the <span class="hlt">aerosol</span> properties over the ocean with POLDER</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deuzé, J. L.; Goloub, P.; Herman, M.; Marchand, A.; Perry, G.; Susana, S.; Tanré, D.</p> <p>2000-06-01</p> <p>The wide field of view <span class="hlt">imaging</span> spectroradiometer Polarization and Directionality of the Earth's Reflectance (POLDER) developed by Centre National d'Etudes Spatiales and operated aboard the Japanese heliosynchronous platform Advanced Earth Observation Satellite (ADEOS) from October 30, 1996, to June 30, 1997, provided the first global systematic measurements of the spectral, directional, and polarized characteristics of the solar radiation reflected by the Earth/atmosphere system. These original observational capabilities offer an opportunity to enhance the characterization of several components of the global environment, especially the oceanic and terrestrial vegetal primary production, the <span class="hlt">aerosol</span> physical and optical properties, and the tridimensional structure and microphysics of clouds. Here we examine the remote sensing of <span class="hlt">aerosols</span> over the oceans. In a first step the <span class="hlt">aerosol</span> optical thickness and Ångström exponent are derived from the radiance measurements. In a second step the polarization measurements are used for the retrieval of the <span class="hlt">aerosol</span> refractive index. The inversion algorithm assumes spherical, nonabsorbing particles with monomodal lognormal size distribution. The adequacy of this modeling is discussed for a representative set of <span class="hlt">aerosol</span> observations. Successful retrieval is generally achieved in the presence of small <span class="hlt">aerosols</span> with Ångström exponent larger than ˜1.0. For such particles, polarization may provide information on the particle refractive index. As the Ångstrom exponent of the particle decreases, the data fitting residual errors increase, especially in polarized light, which prevents the retrieval of the <span class="hlt">aerosol</span> refractive index. The trends of the discrepancies point out two shortcomings of the <span class="hlt">aerosol</span> modeling. The theoretical results systematically underestimate the contribution of small polarizing particles in the polarization measurements for side-scattering angles ranging from 80° to 120°. This indicates very probably that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016tac..confE..30S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016tac..confE..30S"><span id="translatedtitle"><span class="hlt">Aerosols</span> optical propertites in Titan's Detached Haze Layer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seignovert, Benoît; Rannou, Pascal; Lavvas, Panayotis; Cours, Thibaud; West, Robert A.</p> <p>2016-06-01</p> <p>Titan's Detached Haze Layer (DHL) first observed in 1983 by Rages and Pollack during the Voyager 2 [1] is a consistent spherical haze feature surrounding Titan's upper atmosphere and detached from the main haze. Since 2005, the <span class="hlt">Imaging</span> Science Subsystem (ISS) instrument on board the Cassini mission performs a continuous survey of the Titan's atmosphere and confirmed its persistence at 500 km up to the equinox (2009) before its drop and disappearance in 2012 [2]. Previous analyses showed, that this layer corresponds to the transition area between small spherical <span class="hlt">aerosols</span> and large fractal aggregates and play a key role in the <span class="hlt">aerosols</span> formation in Titan's atmosphere [3-5]. In this study we perform UV photometric analyses on ISS observations taken from 2005 to 2007 based on radiative transfer inversion to retrieve <span class="hlt">aerosols</span> particles properties in the DHL (bulk and monomer size, fractal dimension and local density).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26698808','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26698808"><span id="translatedtitle">Atmospheric <span class="hlt">aerosol</span> monitoring by an elastic Scheimpflug lidar system.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mei, Liang; Brydegaard, Mikkel</p> <p>2015-11-30</p> <p>This work demonstrates a new approach - Scheimpflug lidar - for atmospheric <span class="hlt">aerosol</span> monitoring. The atmospheric backscattering echo of a high-power continuous-wave laser diode is received by a Newtonian telescope and recorded by a tilted <span class="hlt">imaging</span> sensor satisfying the Scheimpflug condition. The principles as well as the lidar equation are discussed in details. A Scheimpflug lidar system operating at around 808 nm is developed and employed for continuous atmospheric <span class="hlt">aerosol</span> monitoring at daytime. Localized emission, atmospheric variation, as well as the changes of cloud height are observed from the recorded lidar signals. The extinction coefficient is retrieved according to the slope method for a homogeneous atmosphere. This work opens up new possibilities of using a compact and robust Scheimpflug lidar system for atmospheric <span class="hlt">aerosol</span> remote sensing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26698808','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26698808"><span id="translatedtitle">Atmospheric <span class="hlt">aerosol</span> monitoring by an elastic Scheimpflug lidar system.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mei, Liang; Brydegaard, Mikkel</p> <p>2015-11-30</p> <p>This work demonstrates a new approach - Scheimpflug lidar - for atmospheric <span class="hlt">aerosol</span> monitoring. The atmospheric backscattering echo of a high-power continuous-wave laser diode is received by a Newtonian telescope and recorded by a tilted <span class="hlt">imaging</span> sensor satisfying the Scheimpflug condition. The principles as well as the lidar equation are discussed in details. A Scheimpflug lidar system operating at around 808 nm is developed and employed for continuous atmospheric <span class="hlt">aerosol</span> monitoring at daytime. Localized emission, atmospheric variation, as well as the changes of cloud height are observed from the recorded lidar signals. The extinction coefficient is retrieved according to the slope method for a homogeneous atmosphere. This work opens up new possibilities of using a compact and robust Scheimpflug lidar system for atmospheric <span class="hlt">aerosol</span> remote sensing. PMID:26698808</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFM.A23Q..07M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2014AGUFM.A23Q..07M&link_type=ABSTRACT"><span id="translatedtitle">Novel Measurements of <span class="hlt">Aerosol</span> Particle Interfaces Using Biphasic Microfluidics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Metcalf, A. R.; Dutcher, C. S.</p> <p>2014-12-01</p> <p>Secondary organic <span class="hlt">aerosol</span> (SOA) particles are nearly ubiquitous in the atmosphere and yet there remains large uncertainties in their formation processes and ambient properties. These particles are complex microenvironments, which can contain multiple interfaces due to internal aqueous-organic phase partitioning and to the external liquid-vapor surface. These <span class="hlt">aerosol</span> interfaces can profoundly affect the fate of condensable organic compounds emitted into the atmosphere by altering the way in which organic vapors interact with the ambient <span class="hlt">aerosol</span>. <span class="hlt">Aerosol</span> interfaces affect particle internal structure, species uptake, equilibrium partitioning, activation to cloud condensation or ice nuclei, and optical properties. For example, organic thin films can shield the core of the <span class="hlt">aerosol</span> from the ambient environment, which may disrupt equilibrium partitioning and mass transfer. To improve our ability to accurately predict the fate of SOA in the atmosphere, we must improve our knowledge of <span class="hlt">aerosol</span> interfaces and their interactions with the ambient environment. Few technologies exist to accurately probe <span class="hlt">aerosol</span> interfaces at atmospherically-relevant conditions. In this talk, a novel method using biphasic microscale flows will be introduced for generating, trapping, and perturbing complex interfaces at atmospherically relevant conditions. These microfluidic experiments utilize high-speed <span class="hlt">imaging</span> to monitor interfacial phenomena at the microscale and are performed with phase contrast and fluorescence microscopy on a temperature-controlled inverted microscope stage. From these experiments, interfacial thermodynamic properties such as surface tension, rheological properties such as interfacial moduli, and kinetic properties such as mass transfer coefficients can be measured or inferred. Chemical compositions of the liquid phases studied here span a range of viscosities and include electrolyte and water soluble organic acid species often observed in the atmosphere, such as mixtures</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7028557','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/7028557"><span id="translatedtitle">Mexico City <span class="hlt">aerosol</span> study</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Falcon, Y.I. ); Ramirez, C.R. )</p> <p>1988-01-01</p> <p>Mexico City is located in a valley at high elevation (2,268 m) and is subject to atmospheric inversion related problems similar to those found in Denver, Colorado. In addition, Mexico City has a tropical climate (latitude 19{degrees} 25 minutes N), and therefore has more sunlight available for production of photochemical smog. There are approximately 9.5 million people spread in a 1,500 km{sup 2} (25 sq. mi) urban area, and more than two million automobiles (D.G.P.T. 1979) which use leaded gasoline. Furthermore, Mexico City is the principal industrial center in the country with more than 131,000 industries. The growth of the city has led to a serious air pollution problem, and there is concern over the possible pollutant effects on human health. The authors discuss work done to characterize the chemical composition of the <span class="hlt">aerosol</span>. It is shown that many of the organic compounds which have been detected in urban <span class="hlt">aerosols</span> are carcinogens.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1001114','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1001114"><span id="translatedtitle">How Important Is Organic <span class="hlt">Aerosol</span> Hygroscopicity to <span class="hlt">Aerosol</span> Indirect Forcing?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, Xiaohong; Wang, Jian</p> <p>2010-12-07</p> <p>Organics are among the most abundant <span class="hlt">aerosol</span> components in the atmosphere. However, there are still large uncertainties with emissions of primary organic <span class="hlt">aerosol</span> (POA) and volatile organic compounds (VOCs) (precursor gases of secondary organic <span class="hlt">aerosol</span>, SOA), formation and yield of SOA, and chemical and physical properties (e.g., hygroscopicity) of POA and SOA. All these may have significant impacts on <span class="hlt">aerosol</span> direct and indirect forcing estimated from global models. In this study a modal <span class="hlt">aerosol</span> module (MAM) in the NCAR Community Atmospheric Model (CAM) is used to examine sensitivities of <span class="hlt">aerosol</span> indirect forcing to hygroscopicity (“κ” value) of POA and SOA. Our model simulation indicates that in the present-day condition changing “κ” value of POA from 0 to 0.1 increases the number concentration of cloud condensational nuclei (CCN) at supersaturation S=0.1% by 40-60% over the POA source regions, while changing “κ” value of SOA by ±50% (from 0.14 to 0.07 and 0.21) changes the CCN within 30%. Changes in the in-cloud droplet number concentrations (CDNC) are within 20% in most locations on the globe with the above changes in “κ” value of POA and SOA. Global annual mean anthropogenic <span class="hlt">aerosol</span> indirect forcing (AIF) between present-day (PD) and pre-industrial (PI) conditions change by 0.4 W m-2 with the control run of -1.3 W m-2. AIF reduces with the increase hygroscopicity of organic <span class="hlt">aerosol</span>, indicating the important role of natural organic <span class="hlt">aerosol</span> in buffering the relative change of CDNC from PI to PD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRD..108.8441R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRD..108.8441R"><span id="translatedtitle">PMSE dependence on <span class="hlt">aerosol</span> charge number density and <span class="hlt">aerosol</span> size</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rapp, Markus; Lübken, Franz-Josef; Hoffmann, Peter; Latteck, Ralph; Baumgarten, Gerd; Blix, Tom A.</p> <p>2003-04-01</p> <p>It is commonly accepted that the existence of polar mesosphere summer echoes (PMSEs) depends on the presence of charged <span class="hlt">aerosols</span> since these are comparatively heavy and reduce the diffusion of free electrons due to ambipolar forces. Simple microphysical modeling suggests that this diffusivity reduction is proportional to rA2 (rA = <span class="hlt">aerosol</span> radius) but only if a significant amount of charges is bound on the <span class="hlt">aerosols</span> such that NA∣ZA∣/ne > 1.2 (NA = number of <span class="hlt">aerosols</span>, ZA = <span class="hlt">aerosol</span> charge, ne = number of free electrons). The fact that the background electron profile frequently shows large depletions ("biteouts") at PMSE altitudes is taken as a support for this idea since within biteouts a major fraction of free electrons is missing, i.e., bound on <span class="hlt">aerosols</span>. In this paper, we show from in situ measurements of electron densities and from radar and lidar observations that PMSEs can also exist in regions where only a minor fraction of free electrons is bound on <span class="hlt">aerosols</span>, i.e., with no biteout and with NA∣ZA∣/ne ≪ 1. We show strong experimental evidence that it is instead the product NA∣ZA∣rA2 that is crucial for the existence of PMSEs. For example, small <span class="hlt">aerosol</span> charge can be compensated by large <span class="hlt">aerosol</span> radius. We show that this product replicates the main features of PMSEs, in particular the mean altitude distribution and the altitude of PMSEs in the presence of noctilucent clouds (NLCs). We therefore take this product as a "proxy" for PMSE. The agreement between this proxy and the main characteristics of PMSEs implies that simple microphysical models do not satisfactorily describe PMSE physics and need to be improved. The proxy can easily be used in models of the upper atmosphere to better understand seasonal and geographical variations of PMSEs, for example, the long debated difference between Northern and Southern hemisphere PMSEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991PhDT........90W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991PhDT........90W"><span id="translatedtitle">Inorganic Components of Atmospheric <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wexler, Anthony Stein</p> <p></p> <p>The inorganic components comprise 15% to 50% of the mass of atmospheric <span class="hlt">aerosols</span>. For about the past 10 years the mass of these components was predicted assuming thermodynamic equilibrium between the volatile <span class="hlt">aerosol</span> -phase inorganic species NH_4NO _3 and NH_4Cl and their gas-phase counterparts NH_3, HNO_3, and HCl. In this thesis I examine this assumption and prove that (1) the time scales for equilibration between the gas and <span class="hlt">aerosol</span> phases are often too long for equilibrium to hold, and (2) even when equilibrium holds, transport considerations often govern the size distribution of these <span class="hlt">aerosol</span> components. Water can comprise a significant portion of atmospheric <span class="hlt">aerosols</span> under conditions of high relative humidity, whereas under conditions of sufficiently low relative humidity atmospheric <span class="hlt">aerosols</span> tend to be dry. The deliquescence point is the relative humidity where the <span class="hlt">aerosol</span> goes from a solid dry phase to an aqueous or mixed solid-aqueous phase. In this thesis I derive the temperature dependence of the deliquescence point and prove that in multicomponent solutions the deliquescence point is lower than for corresponding single component solutions. These theories of the transport, thermodynamic, and deliquescent properties of atmospheric <span class="hlt">aerosols</span> are integrated into an <span class="hlt">aerosol</span> inorganics model, AIM. The predictions of AIM compare well to fundamental thermodynamic measurements. Comparison of the prediction of AIM to those of other <span class="hlt">aerosol</span> equilibrium models shows substantial disagreement in the predicted water content at lower relative humidities. The disagreement is due the improved treatment in AIM of the deliquescence properties of multicomponent solutions. In the summer and fall of 1987 the California Air Resources Board conducted the Southern California Air Quality Study, SCAQS, during which atmospheric <span class="hlt">aerosols</span> were measured in Los Angeles. The size and composition of the <span class="hlt">aerosol</span> and the concentrations of their gas phase counterparts were measured. When the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22415968','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22415968"><span id="translatedtitle">Electron mean free path from angle-dependent photoelectron spectroscopy of <span class="hlt">aerosol</span> particles</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Goldmann, Maximilian; Miguel-Sánchez, Javier; West, Adam H. C.; Yoder, Bruce L.; Signorell, Ruth</p> <p>2015-06-14</p> <p>We propose angle-resolved photoelectron spectroscopy of <span class="hlt">aerosol</span> particles as an alternative way to determine the electron mean free path of low energy electrons in solid and liquid materials. The mean free path is obtained from fits of simulated photoemission <span class="hlt">images</span> to experimental ones over a broad range of different <span class="hlt">aerosol</span> particle sizes. The principal advantage of the <span class="hlt">aerosol</span> approach is twofold. First, <span class="hlt">aerosol</span> photoemission studies can be performed for many different materials, including liquids. Second, the size-dependent anisotropy of the photoelectrons can be exploited in addition to size-dependent changes in their kinetic energy. These finite size effects depend in different ways on the mean free path and thus provide more information on the mean free path than corresponding liquid jet, thin film, or bulk data. The present contribution is a proof of principle employing a simple model for the photoemission of electrons and preliminary experimental data for potassium chloride <span class="hlt">aerosol</span> particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19151835','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19151835"><span id="translatedtitle">Satellite remote sensing of dust <span class="hlt">aerosol</span> indirect effects on ice cloud formation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ou, Steve Szu-Cheng; Liou, Kuo-Nan; Wang, Xingjuan; Hansell, Richard; Lefevre, Randy; Cocks, Stephen</p> <p>2009-01-20</p> <p>We undertook a new approach to investigate the <span class="hlt">aerosol</span> indirect effect of the first kind on ice cloud formation by using available data products from the Moderate-Resolution <span class="hlt">Imaging</span> Spectrometer (MODIS) and obtained physical understanding about the interaction between <span class="hlt">aerosols</span> and ice clouds. Our analysis focused on the examination of the variability in the correlation between ice cloud parameters (optical depth, effective particle size, cloud water path, and cloud particle number concentration) and <span class="hlt">aerosol</span> optical depth and number concentration that were inferred from available satellite cloud and <span class="hlt">aerosol</span> data products. Correlation results for a number of selected scenes containing dust and ice clouds are presented, and dust <span class="hlt">aerosol</span> indirect effects on ice clouds are directly demonstrated from satellite observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9882E..0QS','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9882E..0QS"><span id="translatedtitle">Precipitation-<span class="hlt">aerosol</span> relationship over the Indian region during drought and excess summer monsoon years</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Surendran, Sajani; Rajendran, Kavirajan; V. B., Arya</p> <p>2016-05-01</p> <p>This study investigates the <span class="hlt">aerosols</span>-rainfall interaction during Indian summer monsoon and characterizes their difference in drought and excess summer monsoon years, based on MODIS (MODerate Resolution <span class="hlt">Imaging</span> Spectro-radiometer) derived <span class="hlt">Aerosol</span> Optical Depth (AOD) at 550 nm. AOD has been estimated using Level-2 MODIS Terra Data Version 6. AOD in drought years is found to be higher over India compared to excess monsoon years. The total effect of <span class="hlt">aerosols</span> causes reduction of summer rainfall but with distinct differences in their impact during strong and weak summer monsoon years, due to the changes in clouds, radiation, large-scale circulation, and convection. <span class="hlt">Aerosol</span> and cloud characteristics exhibit strong association to rainfall variability in interannual time scales. Variability in cloud effective radius and cloud optical thickness is found to be consistent with <span class="hlt">aerosol</span> effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRD..120.8372L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRD..120.8372L"><span id="translatedtitle">Retrieving the height of smoke and dust <span class="hlt">aerosols</span> by synergistic use of VIIRS, OMPS, and CALIOP observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Jaehwa; Hsu, N. Christina; Bettenhausen, Corey; Sayer, Andrew M.; Seftor, Colin J.; Jeong, Myeong-Jae</p> <p>2015-08-01</p> <p>This study extends the application of the previously developed <span class="hlt">Aerosol</span> Single-scattering albedo and layer Height Estimation (ASHE) algorithm, which was originally applied to smoke <span class="hlt">aerosols</span> only, to both smoke and dust <span class="hlt">aerosols</span> by including nonspherical dust properties in the retrieval process. The main purpose of the algorithm is to derive <span class="hlt">aerosol</span> height information over wide areas using <span class="hlt">aerosol</span> products from multiple satellite sensors simultaneously: <span class="hlt">aerosol</span> optical depth (AOD) and Ångström exponent from the Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS), UV <span class="hlt">aerosol</span> index from the Ozone Mapping and Profiler Suite (OMPS), and total backscatter coefficient profile from the Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization (CALIOP). The case studies suggest that the ASHE algorithm performs well for both smoke and dust <span class="hlt">aerosols</span>, showing root-mean-square error of the retrieved <span class="hlt">aerosol</span> height as compared to CALIOP observations from 0.58 to 1.31 km and mean bias from -0.70 to 1.13 km. In addition, the algorithm shows the ability to retrieve single-scattering albedo to within 0.03 of <span class="hlt">Aerosol</span> Robotic Network inversion data for moderate to thick <span class="hlt">aerosol</span> loadings (AOD of ~1.0). For typical single-layered <span class="hlt">aerosol</span> cases, the estimated uncertainty in the retrieved height ranges from 1.20 to 1.80 km over land and from 1.15 to 1.58 km over ocean when favorable conditions are met. Larger errors are observed for multilayered <span class="hlt">aerosol</span> events, due to the limited sensitivities of the passive sensors to such cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8921M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8921M"><span id="translatedtitle">Evaluation of a size-resolved <span class="hlt">aerosol</span> model based on satellite and ground observations and its implication on <span class="hlt">aerosol</span> forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Xiaoyan; Yu, Fangqun</p> <p>2016-04-01</p> <p>The latest AeroCom phase II experiments have showed a large diversity in the simulations of <span class="hlt">aerosol</span> concentrations, size distribution, vertical profile, and optical properties among 16 detailed global <span class="hlt">aerosol</span> microphysics models, which contribute to the large uncertainty in the predicted <span class="hlt">aerosol</span> radiative forcing and possibly induce the distinct climate change in the future. In the last few years, we have developed and improved a global size-resolved <span class="hlt">aerosol</span> model (Yu and Luo, 2009; Ma et al., 2012; Yu et al., 2012), GEOS-Chem-APM, which is a prognostic multi-type, multi-component, size-resolved <span class="hlt">aerosol</span> microphysics model, including state-of-the-art nucleation schemes and condensation of low volatile secondary organic compounds from successive oxidation aging. The model is one of 16 global models for AeroCom phase II and participated in a couple of model inter-comparison experiments. In this study, we employed multi-year <span class="hlt">aerosol</span> optical depth (AOD) data from 2004 to 2012 taken from ground-based <span class="hlt">Aerosol</span> Robotic Network (AERONET) measurements and Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), Multiangle <span class="hlt">Imaging</span> SpectroRadiometer (MISR) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite retrievals to evaluate the performance of the GEOS-Chem-APM in predicting <span class="hlt">aerosol</span> optical depth, including spatial distribution, reginal variation and seasonal variabilities. Compared to the observations, the modelled AOD is overall good over land, but quite low over ocean possibly due to low sea salt emission in the model and/or higher AOD in satellite retrievals, specifically MODIS and MISR. We chose 72 AERONET sites having at least 36 months data available and representative of high spatial domain to compare with the model and satellite data. Comparisons in various representative regions show that the model overall agrees well in the major anthropogenic emission regions, such as Europe, East Asia and North America. Relative to the observations, the modelled AOD is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015539','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015539"><span id="translatedtitle">International Cooperative for <span class="hlt">Aerosol</span> Prediction Workshop on <span class="hlt">Aerosol</span> Forecast Verification</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Benedetti, Angela; Reid, Jeffrey S.; Colarco, Peter R.</p> <p>2011-01-01</p> <p>The purpose of this workshop was to reinforce the working partnership between centers who are actively involved in global <span class="hlt">aerosol</span> forecasting, and to discuss issues related to forecast verification. Participants included representatives from operational centers with global <span class="hlt">aerosol</span> forecasting requirements, a panel of experts on Numerical Weather Prediction and Air Quality forecast verification, data providers, and several observers from the research community. The presentations centered on a review of current NWP and AQ practices with subsequent discussion focused on the challenges in defining appropriate verification measures for the next generation of <span class="hlt">aerosol</span> forecast systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19890057240&hterms=sage+journals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsage%2Bjournals','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19890057240&hterms=sage+journals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsage%2Bjournals"><span id="translatedtitle">SAGE II <span class="hlt">aerosol</span> data validation based on retrieved <span class="hlt">aerosol</span> model size distribution from SAGE II <span class="hlt">aerosol</span> measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, Pi-Huan; Mccormick, M. P.; Mcmaster, L. R.; Chu, W. P.; Swissler, T. J.; Osborn, M. T.; Russell, P. B.; Oberbeck, V. R.; Livingston, J.; Rosen, J. M.</p> <p>1989-01-01</p> <p>Consideration is given to <span class="hlt">aerosol</span> correlative measurements experiments for the Stratospheric <span class="hlt">Aerosol</span> and Gas Experiment (SAGE) II, conducted between November 1984 and July 1986. The correlative measurements were taken with an impactor/laser probe, a dustsonde, and an airborne 36-cm lidar system. The primary <span class="hlt">aerosol</span> quantities measured by the ground-based instruments are compared with those calculated from the <span class="hlt">aerosol</span> size distributions from SAGE II <span class="hlt">aerosol</span> extinction measurements. Good agreement is found between the two sets of measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23581749','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23581749"><span id="translatedtitle">Evaluating UVA <span class="hlt">aerosol</span> optical depth using a smartphone camera.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Igoe, Damien P; Parisi, Alfio V; Carter, Brad</p> <p>2013-01-01</p> <p>This research evaluates a smartphone complementary metal oxide semiconductor (CMOS) <span class="hlt">image</span> sensor's ability to detect and quantify incident solar UVA radiation and subsequently, <span class="hlt">aerosol</span> optical depth at 340 and 380 nm. Earlier studies revealed that the consumer grade CMOS sensor has inherent UVA sensitivities, despite attenuating effects of the lens. Narrow bandpass and neutral density filters were used to protect the <span class="hlt">image</span> sensor and to not allow saturation of the solar <span class="hlt">images</span> produced. Observations were made on clear days, free from clouds. The results of this research demonstrate that there is a definable response to changing solar irradiance and <span class="hlt">aerosol</span> optical depth can be measured within 5% and 10% error margins at 380 and 340 nm respectively. The greater relative error occurs at lower wavelengths (340 nm) due to increased atmospheric scattering effects, particularly at higher air masses and due to lower signal to noise ratio in the <span class="hlt">image</span> sensor. The relative error for solar irradiance was under 1% for observations made at 380 nm. The results indicate that the smartphone <span class="hlt">image</span> sensor, with additional external narrow bandpass and neutral density filters can be used as a field sensor to evaluate solar UVA irradiance and <span class="hlt">aerosol</span> optical depth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.A53A0249C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.A53A0249C"><span id="translatedtitle">Validations of GOES-R ABI <span class="hlt">Aerosol</span> Products</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ciren, P.; Laszlo, I.; Kondragunta, S.; Liu, H.; Zhou, M.</p> <p>2009-12-01</p> <p>High temporal resolution observations from geostationary platform provide unique benefits for monitoring the development of air pollution event. Especially, observations of multi-visible channels in the future GOES-R ABI provide more capability for characterizing air quality. GOES-R ABI Air Quality products include <span class="hlt">Aerosol</span> detection product and suspended matter/AOD product. The first one is to detect the presence of smoke/dust; the second one is to quantify the amount of particles in the air in terms of light attenuation, and consequently inferred concentration of particles. In this presentation, we focus on the demonstration of the performance of the developed products through a comprehensive validation process. In the current pre-launch stage, MODIS radiances at bands similar to those of ABI are used as proxy. As for the suspended matter/AOD product, truth data include observations from ground-based instruments at the AERONET stations, MODIS collection 5 <span class="hlt">aerosol</span> products, and <span class="hlt">aerosol</span> product from CALIPSO (Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observation). For <span class="hlt">aerosol</span> detection product, truth data include MODIS RGB <span class="hlt">images</span> and CALIPO Vertical Feature Mask Products. Through comparisons with global observations from MODIS, point observations from AERONET, and narrow-track observations from CALIPSO, accuracy and precision (for AOD only) are evaluated for both products. In addition, a validation system which includes not only the evaluation with historical data, but also monitoring the products qualities with near-real time observations, is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22486582','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22486582"><span id="translatedtitle">SU-C-201-03: Coded Aperture Gamma-Ray <span class="hlt">Imaging</span> Using Pixelated Semiconductor Detectors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Joshi, S; Kaye, W; Jaworski, J; He, Z</p> <p>2015-06-15</p> <p>Purpose: Improved localization of gamma-ray emissions from radiotracers is essential to the progress of nuclear medicine. Polaris is a portable, room-temperature operated gamma-ray <span class="hlt">imaging</span> spectrometer composed of two 3×3 arrays of thick CdZnTe (CZT) detectors, which detect gammas between 30keV and 3MeV with energy resolution of <1% FWHM at 662keV. Compton <span class="hlt">imaging</span> is used to map out source distributions in 4-pi space; however, is only effective above 300keV where Compton scatter is dominant. This work extends <span class="hlt">imaging</span> to photoelectric energies (<300keV) using coded aperture <span class="hlt">imaging</span> (<span class="hlt">CAI</span>), which is essential for localization of Tc-99m (140keV). Methods: <span class="hlt">CAI</span>, similar to the pinhole camera, relies on an attenuating mask, with open/closed elements, placed between the source and position-sensitive detectors. Partial attenuation of the source results in a “shadow” or count distribution that closely matches a portion of the mask pattern. Ideally, each source direction corresponds to a unique count distribution. Using backprojection reconstruction, the source direction is determined within the field of view. The knowledge of 3D position of interaction results in improved <span class="hlt">image</span> quality. Results: Using a single array of detectors, a coded aperture mask, and multiple Co-57 (122keV) point sources, <span class="hlt">image</span> reconstruction is performed in real-time, on an event-by-event basis, resulting in <span class="hlt">images</span> with an angular resolution of ∼6 degrees. Although material nonuniformities contribute to <span class="hlt">image</span> degradation, the superposition of <span class="hlt">images</span> from individual detectors results in improved SNR. <span class="hlt">CAI</span> was integrated with Compton <span class="hlt">imaging</span> for a seamless transition between energy regimes. Conclusion: For the first time, <span class="hlt">CAI</span> has been applied to thick, 3D position sensitive CZT detectors. Real-time, combined <span class="hlt">CAI</span> and Compton <span class="hlt">imaging</span> is performed using two 3×3 detector arrays, resulting in a source distribution in space. This system has been commercialized by H3D, Inc. and is being acquired for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1077560','SCIGOV-DOEDE'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1077560"><span id="translatedtitle">AERONET: The <span class="hlt">Aerosol</span> Robotic Network</span></a></p> <p><a target="_blank" href="http://www.osti.gov/dataexplorer">DOE Data Explorer</a></p> <p></p> <p></p> <p>The AERONET (<span class="hlt">AErosol</span> RObotic NETwork) program is a federation of ground-based remote sensing <span class="hlt">aerosol</span> networks established by NASA and LOA-PHOTONS (CNRS) and is greatly expanded by collaborators from national agencies, institutes, universities, individual scientists, and partners. The program provides a long-term, continuous and readily accessible public domain database of <span class="hlt">aerosol</span> optical, mircrophysical and radiative properties for <span class="hlt">aerosol</span> research and characterization, validation of satellite retrievals, and synergism with other databases. The network imposes standardization of instruments, calibration, processing and distribution. AERONET collaboration provides globally distributed observations of spectral <span class="hlt">aerosol</span> optical Depth (AOD), inversion products, and precipitable water in diverse <span class="hlt">aerosol</span> regimes. <span class="hlt">Aerosol</span> optical depth data are computed for three data quality levels: Level 1.0 (unscreened), Level 1.5 (cloud-screened), and Level 2.0 (cloud screened and quality-assured). Inversions, precipitable water, and other AOD-dependent products are derived from these levels and may implement additional quality checks.[Copied from http://aeronet.gsfc.nasa.gov/new_web/system_descriptions.html</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AMTD....810319N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AMTD....810319N"><span id="translatedtitle">Monitoring and tracking the trans-Pacific transport of <span class="hlt">aerosols</span> using multi-satellite <span class="hlt">aerosol</span> optical depth retrievals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Naeger, A. R.; Gupta, P.; Zavodsky, B.; McGrath, K. M.</p> <p>2015-10-01</p> <p>The primary goal of this study was to generate a near-real time (NRT) <span class="hlt">aerosol</span> optical depth (AOD) product capable of providing a comprehensive understanding of the <span class="hlt">aerosol</span> spatial distribution over the Pacific Ocean in order to better monitor and track the trans-Pacific transport of <span class="hlt">aerosols</span>. Therefore, we developed a NRT product that takes advantage of observations from both low-earth orbiting and geostationary satellites. In particular, we utilize AOD products from the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) and Suomi National Polar-orbiting Partnership (NPP) Visible Infrared <span class="hlt">Imaging</span> Radiometer Suite (VIIRS) satellites. Then, we combine these AOD products with our own retrieval algorithms developed for the NOAA Geostationary Operational Environmental Satellite (GOES-15) and Japan Meteorological Agency (JMA) Multi-functional Transport Satellite (MTSAT-2) to generate a NRT daily AOD composite product. We present examples of the daily AOD composite product for a case study of trans-Pacific transport of Asian pollution and dust <span class="hlt">aerosols</span> in mid-March 2014. Overall, the new product successfully tracks this <span class="hlt">aerosol</span> plume during its trans-Pacific transport to the west coast of North America. However, we identify several areas across the domain of interest from Asia to North America where the new product can encounter significant uncertainties due to the inclusion of the geostationary AOD retrievals. The uncertainties associated with geostationary AOD retrievals are expected to be minimized after the successful launch of the next-generation advanced NOAA GOES-R and recently launched JMA Himawari satellites. Observations from these advanced satellites will ultimately provide an enhanced understanding of the spatial and temporal distribution of <span class="hlt">aerosols</span> over the Pacific.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20030112964&hterms=lighthouse&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dlighthouse','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20030112964&hterms=lighthouse&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dlighthouse"><span id="translatedtitle">Towards Improved MODIS <span class="hlt">Aerosol</span> Retrieval over the US East Coast Region: Re-examining the <span class="hlt">Aerosol</span> Model and Surface Assumptions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Levy, R. C.; Remer, L. A.; Kaufman, Y. J.; Holben, B. N.</p> <p>2002-01-01</p> <p>The MODerate resolution <span class="hlt">Imaging</span> Spectrometer (MODIS) aboard the Terra and recently the Aqua platform, produces a set of <span class="hlt">aerosol</span> products over both ocean and land regions. Previous validation efforts have shown that from a global perspective, <span class="hlt">aerosol</span> optical depth (AOD) is successfully retrieved from MODIS. Even over coastal regions, the over- land and over-ocean retrievals are consistent with each other, and well matched with ground-based sunphotometer measurements (such as AERONET). However, the East Coast of the United States is one region where there is consistently a discrepancy between land and ocean retrievals. Over the ocean, MODIS AODs are consistent with coastal sunphotometer measurements, but over land, AODs are consistently over- estimated. In this study we use field data from the Chesapeake Lighthouse and Aircraft Measurements for Satellites experiment (CLAMS), (held during summer 2001) to determine the <span class="hlt">aerosol</span> properties at a number of sites. Using the 6-S radiative transfer package, we compute simulated satellite radiances and compare them with observed MODIS radiances. We believe that the AOD over-estimation is not likely due to an incorrect choice of the urban/industrial <span class="hlt">aerosol</span> models. Using 6-S to do an atmospheric correction for a very low AOD case, we show rather, that the discrepancies are likely a result of incorrect assumptions about the surface reflectance properties. Understanding and improving MODIS retrievals over the East Coast will not only improve the global quality of MODIS, but also would enable the use of MODIS as a tool for monitoring regional <span class="hlt">aerosol</span> events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1012284','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1012284"><span id="translatedtitle">The effect of <span class="hlt">aerosol</span> vertical profiles on satellite-estimated surface particle sulfate concentrations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, Yang; Wang, Zifeng; Wang, Jun; Ferrare, Richard A.; Newsom, Rob K.; Welton, Ellsworth J.</p> <p>2011-02-15</p> <p>The <span class="hlt">aerosol</span> vertical distribution is an important factor in determining the relationship between satellite retrieved <span class="hlt">aerosol</span> optical depth (AOD) and ground-level fine particle pollution concentrations. We evaluate how <span class="hlt">aerosol</span> profiles measured by ground-based lidar and simulated by models can help improve the association between AOD retrieved by the Multi-angle <span class="hlt">Imaging</span> Spectroradiometer (MISR) and fine particle sulfate (SO4) concentrations using matched data at two lidar sites. At the Goddard Space Flight Center (GSFC) site, both lidar and model <span class="hlt">aerosol</span> profiles marginally improve the association between SO4 concentrations and MISR fractional AODs, as the correlation coefficient between cross-validation (CV) and observed SO4 concentrations changes from 0.87 for the no-scaling model to 0.88 for models scaled with <span class="hlt">aerosol</span> vertical profiles. At the GSFC site, a large amount of urban <span class="hlt">aerosols</span> resides in the well-mixed boundary layer so the column fractional AODs are already excellent indicators of ground-level particle pollution. In contrast, at the Atmospheric Radiation Measurement Program (ARM) site with relatively low <span class="hlt">aerosol</span> loadings, scaling substantially improves model performance. The correlation coefficient between CV and observed SO4 concentrations is increased from 0.58 for the no-scaling model to 0.76 in the GEOS-Chem scaling model, and the model bias is reduced from 17% to 9%. In summary, despite the inaccuracy due to the coarse horizontal resolution and the challenges of simulating turbulent mixing in the boundary layer, GEOS-Chem simulated <span class="hlt">aerosol</span> profiles can still improve methods for estimating surface <span class="hlt">aerosol</span> (SO4) mass from satellite-based AODs, particularly in rural areas where <span class="hlt">aerosols</span> in the free troposphere and any long-range transport of <span class="hlt">aerosols</span> can significantly contribute to the column AOD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRD..117.3202W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRD..117.3202W"><span id="translatedtitle">Critical reflectance derived from MODIS: Application for the retrieval of <span class="hlt">aerosol</span> absorption over desert regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wells, Kelley C.; Martins, J. Vanderlei; Remer, Lorraine A.; Kreidenweis, Sonia M.; Stephens, Graeme L.</p> <p>2012-02-01</p> <p>The determination of <span class="hlt">aerosol</span> direct radiative forcing over desert regions requires accurate information about the <span class="hlt">aerosol</span> single-scattering albedo (SSA); however, the brightness of desert surfaces in the visible and near-IR range complicates the retrieval of <span class="hlt">aerosol</span> optical properties using passive space-based measurements. Here we use the critical reflectance method to retrieve spectral <span class="hlt">aerosol</span> absorption from space over North Africa, a desert region that is predominantly impacted by absorbing dust and biomass burning <span class="hlt">aerosol</span>. We examine the sensitivity of the critical reflectance parameter to <span class="hlt">aerosol</span> physical and optical properties that are representative of the region, and we find that the critical reflectance has low sensitivity to assumptions of <span class="hlt">aerosol</span> size and refractive index for dust-like particles, except at scattering angles near 180°, which should be avoided with this method. We use our findings to retrieve spectral SSA from critical reflectance derived from Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) reflectances in the vicinity of two <span class="hlt">Aerosol</span> Robotic Network (AERONET) stations: Tamanrasset, in the Algerian Sahara, and Banizoumbou, in the Sahel. We retrieve lower <span class="hlt">aerosol</span> SSAs at Banizoumbou, which is often impacted by dust-smoke mixtures, and higher SSAs at Tamanrasset, where pure desert dust is the dominant <span class="hlt">aerosol</span>. Our results generally fall within the AERONET uncertainty envelopes, although at Banizoumbou we retrieve a spectral dependence different from that of AERONET. On the basis of our analysis, we expect to be able to retrieve SSA from critical reflectance for pure dust with an uncertainty of 0.02 and to provide spatial and spectral SSA information that will help reduce current uncertainties in the <span class="hlt">aerosol</span> radiative forcing over desert regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeCoA.183..176H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeCoA.183..176H"><span id="translatedtitle">Microstructural constraints on complex thermal histories of refractory <span class="hlt">CAI</span>-like objects in an amoeboid olivine aggregate from the ALHA77307 CO3.0 chondrite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Han, Jangmi; Brearley, Adrian J.</p> <p>2016-06-01</p> <p>We have carried out a FIB/TEM study of refractory <span class="hlt">CAI</span>-like objects in one AOA from the ALHA77307 CO3.0 chondrite. The <span class="hlt">CAI</span>-like objects in the AOA consist of a zoned sequence with a spinel-rich core through an intergrowth layer of spinel and Al-Ti-rich diopside to a diopside rim. The spinel-rich core consists of polycrystalline aggregates of spinel and ±minor melilite showing equilibrated grain boundary textures. The intergrowth layer contains fine-grained diopside and spinel with minor anorthite with highly curved and embayed grain boundaries. The diopside rim consists of polycrystalline aggregates of diopside. The compositions of pyroxene change significantly outward from Al-Ti-rich diopside in contact with the spinel-rich core to Al-Ti-poor diopside next to the surrounding olivine of the AOA. Overall microstructural and chemical characteristics suggest that the spinel-rich core formed under equilibrium conditions whereas the intergrowth layer is the result of reactions that occurred under conditions that departed significantly from equilibrium. The remarkable changes in formation conditions of the <span class="hlt">CAI</span>-like objects may have been achieved by transport and injection of refractory objects into a region of a partially-condensed, Ca,Ti-saturated gas which reacted with spinel and melilite to form Al-Ti-rich diopside. Crystallographically-oriented TiO2 nanoparticles decorate the grain boundaries between spinel grains and between spinel and Al-Ti-rich diopside grains. During the disequilibrium back-reaction of spinel with a partially-condensed, Ca,Ti-saturated gas, metastable TiO2 nanoparticles may have condensed by an epitaxial nucleation mechanism and grown on the surface of spinel. These TiO2 nanoparticles are disordered intergrowths of the two TiO2 polymorphs, anatase and rutile. These nanoparticles are inferred to have nucleated as anatase that underwent partial transformation into rutile. The local presence of the TiO2 nanoparticles and intergrowth of anatase and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23382231','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23382231"><span id="translatedtitle"><span class="hlt">Aerosol</span> growth in Titan's ionosphere.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lavvas, Panayotis; Yelle, Roger V; Koskinen, Tommi; Bazin, Axel; Vuitton, Véronique; Vigren, Erik; Galand, Marina; Wellbrock, Anne; Coates, Andrew J; Wahlund, Jan-Erik; Crary, Frank J; Snowden, Darci</p> <p>2013-02-19</p> <p>Photochemically produced <span class="hlt">aerosols</span> are common among the atmospheres of our solar system and beyond. Observations and models have shown that photochemical <span class="hlt">aerosols</span> have direct consequences on atmospheric properties as well as important astrobiological ramifications, but the mechanisms involved in their formation remain unclear. Here we show that the formation of <span class="hlt">aerosols</span> in Titan's upper atmosphere is directly related to ion processes, and we provide a complete interpretation of observed mass spectra by the Cassini instruments from small to large masses. Because all planetary atmospheres possess ionospheres, we anticipate that the mechanisms identified here will be efficient in other environments as well, modulated by the chemical complexity of each atmosphere. PMID:23382231</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1224026','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1224026"><span id="translatedtitle">eDPS <span class="hlt">Aerosol</span> Collection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Venzie, J.</p> <p>2015-10-13</p> <p>The eDPS <span class="hlt">Aerosol</span> Collection project studies the fundamental physics of electrostatic <span class="hlt">aerosol</span> collection for national security applications. The interpretation of <span class="hlt">aerosol</span> data requires understanding and correcting for biases introduced from particle genesis through collection and analysis. The research and development undertaken in this project provides the basis for both the statistical correction of existing equipment and techniques; as well as, the development of new collectors and analytical techniques designed to minimize unwanted biases while improving the efficiency of locating and measuring individual particles of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A23L..03P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A23L..03P"><span id="translatedtitle"><span class="hlt">Aerosol</span> Climate Time Series Evaluation In ESA <span class="hlt">Aerosol</span>_cci</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Popp, T.; de Leeuw, G.; Pinnock, S.</p> <p>2015-12-01</p> <p>Within the ESA Climate Change Initiative (CCI) <span class="hlt">Aerosol</span>_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of <span class="hlt">aerosol</span> information from European sensors. By the end of 2015 full mission time series of 2 GCOS-required <span class="hlt">aerosol</span> parameters are completely validated and released: <span class="hlt">Aerosol</span> Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing <span class="hlt">Aerosol</span> Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary <span class="hlt">aerosol</span> properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer), absorption information and <span class="hlt">aerosol</span> layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which are also validated. The paper will summarize and discuss the results of major reprocessing and validation conducted in 2015. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension with successor instruments of the Sentinel family will be described and the complementarity of the different satellite <span class="hlt">aerosol</span> products</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005PNAS..10211207K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005PNAS..10211207K"><span id="translatedtitle">The effect of smoke, dust, and pollution <span class="hlt">aerosol</span> on shallow cloud development over the Atlantic Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaufman, Yoram J.; Koren, Ilan; Remer, Lorraine A.; Rosenfeld, Daniel; Rudich, Yinon</p> <p>2005-08-01</p> <p>Clouds developing in a polluted environment tend to have more numerous but smaller droplets. This property may lead to suppression of precipitation and longer cloud lifetime. Absorption of incoming solar radiation by <span class="hlt">aerosols</span>, however, can reduce the cloud cover. The net <span class="hlt">aerosol</span> effect on clouds is currently the largest uncertainty in evaluating climate forcing. Using large statistics of 1-km resolution MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer) satellite data, we study the <span class="hlt">aerosol</span> effect on shallow water clouds, separately in four regions of the Atlantic Ocean, for June through August 2002: marine <span class="hlt">aerosol</span> (30°S-20°S), smoke (20°S-5°N), mineral dust (5°N-25°N), and pollution <span class="hlt">aerosols</span> (30°N- 60°N). All four <span class="hlt">aerosol</span> types affect the cloud droplet size. We also find that the coverage of shallow clouds increases in all of the cases by 0.2-0.4 from clean to polluted, smoky, or dusty conditions. Covariability analysis with meteorological parameters associates most of this change to <span class="hlt">aerosol</span>, for each of the four regions and 3 months studied. In our opinion, there is low probability that the net <span class="hlt">aerosol</span> effect can be explained by coincidental, unresolved, changes in meteorological conditions that also accumulate <span class="hlt">aerosol</span>, or errors in the data, although further in situ measurements and model developments are needed to fully understand the processes. The radiative effect at the top of the atmosphere incurred by the <span class="hlt">aerosol</span> effect on the shallow clouds and solar radiation is -11 ± 3 W/m2 for the 3 months studied; 2/3 of it is due to the <span class="hlt">aerosol</span>-induced cloud changes, and 1/3 is due to <span class="hlt">aerosol</span> direct radiative effect. Author contributions: Y.J.K., I.K., L.A.R., D.R., and Y.R. designed research; Y.J.K., I.K., and L.A.R. performed research; Y.J.K., I.K., and L.A.R. analyzed data; Y.J.K. wrote the paper; I.K. and L.A.R. also participated in writing the paper; D.R. provided cloud physics context for the analysis; and D.R. and Y.R. participated in data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A43A0262J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A43A0262J"><span id="translatedtitle">Characterization of smoke <span class="hlt">aerosols</span> over the Indochina Peninsula from multi-platform satellite observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jeong, M. J.; Hsu, N. Y. C.; Lee, J.; Sayer, A. M.; Bettenhausen, C.; Huang, J.</p> <p>2015-12-01</p> <p>Multi-faceted near-simultaneous observations from the sensors aboard multiple satellite platforms, so called the A-Train, are utilized to characterize the spatial distributions and the optical properties of smoke <span class="hlt">aerosols</span> over the Indochina Peninsula. Observations from the A-Train sensors, especially, MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), Ozone Monitoring Instrument (OMI), and Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization (CALIOP), are synthesized to retrieve single-scattering albedo (SSA) and effective <span class="hlt">aerosol</span> layer height (ALH) of BBS <span class="hlt">aerosols</span> in the region. The retrieval algorithm extracts the absorption and height information about smoke <span class="hlt">aerosols</span>, which is lumped into ultraviolet spectra at the top of the atmosphere, by taking the most reliable information contents that each satellite measurement can deliver. The results of retrieved SSA and ALH showed reasonable agreements with in-situ measurements, <span class="hlt">AEROsol</span> Robotic NETwork (AERONET) data, and lidar-based observations. The uncertainty and sensitivity of the retrieval algorithm are also presented. The retrieved quantities are then used together with other satellite datasets to characterize the three-dimensional distributions of smoke <span class="hlt">aerosols</span> over the Indochina Peninsular during the boreal spring time. Given the frequent horizontal collocations of smoke and clouds in the region, implication of smoke vertical distributions for long-range transports is also discussed. The results of this study are anticipated to advance our understanding on the climatic impacts of the smoke <span class="hlt">aerosols</span> in the region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.A23A0263M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.A23A0263M"><span id="translatedtitle">MODIS <span class="hlt">aerosol</span> product at 3 km spatial resolution for urban and air quality studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mattoo, S.; Remer, L. A.; Levy, R. C.; Holben, B. N.; Smirnov, A.</p> <p>2008-12-01</p> <p>The MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) aboard the Terra and Aqua satellites has been producing an <span class="hlt">aerosol</span> product since early 2000. The original product reports <span class="hlt">aerosol</span> optical depth and a variety of other <span class="hlt">aerosol</span> parameters at a spatial resolution of 10 km over both land and ocean. The 10 km product is actually constructed from 500 m pixels, which permits a strict selection process to choose the "best" or "cleanest" pixels in each 10 km square for use in the <span class="hlt">aerosol</span> retrieval. Thus, the original 10 km product provides a useful product, accurate in many applications. However, the 10 km product can miss narrow <span class="hlt">aerosol</span> plumes and the spatial variability associated with urban air pollution. The MODIS <span class="hlt">aerosol</span> team will be introducing a finer resolution <span class="hlt">aerosol</span> product over land regions in the next release of the product (Collection 6). The new product will be produced at 3 km resolution. It is based on the same procedures as the original product and benefits from the same spatial variability criteria for finding and masking cloudy pixels. The 3 km product does capture the higher spatial variability associated with individual <span class="hlt">aerosol</span> plumes. However, it is noisier than the 10 km product. Both products will be available operationally in Collection 6. The new 3km product offers new synergistic possibilities with PM2.5 monitoring networks, AERONET and various air quality models such as CMAQ.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008491','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008491"><span id="translatedtitle">Biomass Burning <span class="hlt">Aerosol</span> Absorption Measurements with MODIS Using the Critical Reflectance Method</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhu, Li; Martins, Vanderlei J.; Remer, Lorraine A.</p> <p>2010-01-01</p> <p>This research uses the critical reflectance technique, a space-based remote sensing method, to measure the spatial distribution of <span class="hlt">aerosol</span> absorption properties over land. Choosing two regions dominated by biomass burning <span class="hlt">aerosols</span>, a series of sensitivity studies were undertaken to analyze the potential limitations of this method for the type of <span class="hlt">aerosol</span> to be encountered in the selected study areas, and to show that the retrieved results are relatively insensitive to uncertainties in the assumptions used in the retrieval of smoke <span class="hlt">aerosol</span>. The critical reflectance technique is then applied to Moderate Resolution <span class="hlt">Imaging</span> Spectrometer (MODIS) data to retrieve the spectral <span class="hlt">aerosol</span> single scattering albedo (SSA) in South African and South American 35 biomass burning events. The retrieved results were validated with collocated <span class="hlt">Aerosol</span> Robotic Network (AERONET) retrievals. One standard deviation of mean MODIS retrievals match AERONET products to within 0.03, the magnitude of the AERONET uncertainty. The overlap of the two retrievals increases to 88%, allowing for measurement variance in the MODIS retrievals as well. The ensemble average of MODIS-derived SSA for the Amazon forest station is 0.92 at 670 nm, and 0.84-0.89 for the southern African savanna stations. The critical reflectance technique allows evaluation of the spatial variability of SSA, and shows that SSA in South America exhibits higher spatial variation than in South Africa. The accuracy of the retrieved <span class="hlt">aerosol</span> SSA from MODIS data indicates that this product can help to better understand 44 how <span class="hlt">aerosols</span> affect the regional and global climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AtmRe..84..201B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AtmRe..84..201B"><span id="translatedtitle"><span class="hlt">Aerosol</span> climatology from ground-based measurements for the southern North Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Behnert, Irina; Matthias, Volker; Doerffer, Roland</p> <p>2007-05-01</p> <p>An <span class="hlt">aerosol</span> climatology over the southern North Sea region has been set up using <span class="hlt">aerosol</span> optical properties derived from regular sunphotometer (AERONET) and lidar (EARLINET) measurements between April and September for the years 2000-2003. Data from four AERONET sites in the North Sea coastal region (Helgoland Island, Oostende, Hamburg and Lille) and, for comparison purposes, also from two "maritime sites" (Rame Head and Azores Island) are selected. The variability of the <span class="hlt">aerosol</span> optical depth τa(500) and the spatial distribution of <span class="hlt">aerosol</span> optical depth τa(500), Ångström wavelength exponent α440-870 , as well as of retrieved microphysical <span class="hlt">aerosol</span> parameters (single scattering albedo, index of refraction, particle size distribution) are studied. The 4 years of observations show great similarities between the North Sea coastal sites and Helgoland Island. Although 70 km separated from the coast, the <span class="hlt">aerosol</span> optical properties found at the island are much closer to those at Hamburg, Oostende and Lille than at the maritime sites Rame Head and Azores. Compared to the standard <span class="hlt">aerosol</span> models differences in the Ångström wavelength exponent α440-870 , the single scattering albedo and the refractive index are detected. Based on these observations a new <span class="hlt">aerosol</span> model for the atmospheric correction of coastal water reflectance spectra of the <span class="hlt">imaging</span> spectrometer MERIS/ENVISAT was set up, which meets in particular the higher Ångström wavelength exponent of the coastal sites compared to standard maritime conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A31B0036L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A31B0036L"><span id="translatedtitle">Observationally-constrained estimates of <span class="hlt">aerosol</span> optical depths (AODs) over East Asia via data assimilation techniques</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, K.; Lee, S.; Song, C. H.</p> <p>2015-12-01</p> <p>Not only <span class="hlt">aerosol</span>'s direct effect on climate by scattering and absorbing the incident solar radiation, but also they indirectly perturbs the radiation budget by influencing microphysics and dynamics of clouds. <span class="hlt">Aerosols</span> also have a significant adverse impact on human health. With an importance of <span class="hlt">aerosols</span> in climate, considerable research efforts have been made to quantify the amount of <span class="hlt">aerosols</span> in the form of the <span class="hlt">aerosol</span> optical depth (AOD). AOD is provided with ground-based <span class="hlt">aerosol</span> networks such as the <span class="hlt">Aerosol</span> Robotic NETwork (AERONET), and is derived from satellite measurements. However, these observational datasets have a limited areal and temporal coverage. To compensate for the data gaps, there have been several studies to provide AOD without data gaps by assimilating observational data and model outputs. In this study, AODs over East Asia simulated with the Community Multi-scale Air Quality (CMAQ) model and derived from the Geostationary Ocean Color <span class="hlt">Imager</span> (GOCI) observation are interpolated via different data assimilation (DA) techniques such as Cressman's method, Optimal Interpolation (OI), and Kriging for the period of the Distributed Regional <span class="hlt">Aerosol</span> Gridded Observation Networks (DRAGON) Campaign (March - May 2012). Here, the interpolated results using the three DA techniques are validated intensively by comparing with AERONET AODs to examine the optimal DA method providing the most reliable AODs over East Asia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1652..183R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1652..183R"><span id="translatedtitle">Stratospheric <span class="hlt">aerosol</span> geoengineering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robock, Alan</p> <p>2015-03-01</p> <p>The Geoengineering Model Intercomparison Project, conducting climate model experiments with standard stratospheric <span class="hlt">aerosol</span> injection scenarios, has found that insolation reduction could keep the global average temperature constant, but global average precipitation would reduce, particularly in summer monsoon regions around the world. Temperature changes would also not be uniform; the tropics would cool, but high latitudes would warm, with continuing, but reduced sea ice and ice sheet melting. Temperature extremes would still increase, but not as much as without geoengineering. If geoengineering were halted all at once, there would be rapid temperature and precipitation increases at 5-10 times the rates from gradual global warming. The prospect of geoengineering working may reduce the current drive toward reducing greenhouse gas emissions, and there are concerns about commercial or military control. Because geoengineering cannot safely address climate change, global efforts to reduce greenhouse gas emissions and to adapt are crucial to address anthropogenic global warming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22391276','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22391276"><span id="translatedtitle">Stratospheric <span class="hlt">aerosol</span> geoengineering</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Robock, Alan</p> <p>2015-03-30</p> <p>The Geoengineering Model Intercomparison Project, conducting climate model experiments with standard stratospheric <span class="hlt">aerosol</span> injection scenarios, has found that insolation reduction could keep the global average temperature constant, but global average precipitation would reduce, particularly in summer monsoon regions around the world. Temperature changes would also not be uniform; the tropics would cool, but high latitudes would warm, with continuing, but reduced sea ice and ice sheet melting. Temperature extremes would still increase, but not as much as without geoengineering. If geoengineering were halted all at once, there would be rapid temperature and precipitation increases at 5–10 times the rates from gradual global warming. The prospect of geoengineering working may reduce the current drive toward reducing greenhouse gas emissions, and there are concerns about commercial or military control. Because geoengineering cannot safely address climate change, global efforts to reduce greenhouse gas emissions and to adapt are crucial to address anthropogenic global warming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/231056','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/231056"><span id="translatedtitle"><span class="hlt">Aerosol</span> lidar ``M4``</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shelevoy, C.D.; Andreev, Y.M. |</p> <p>1994-12-31</p> <p>Small carrying <span class="hlt">aerosol</span> lidar in which is used small copper vapor laser ``Malachite`` as source of sounding optical pulses is described. The advantages of metal vapor laser and photon counting mode in acquisition system of lidar gave ability to get record results: when lidar has dimensions (1 x .6 x .3 m) and weight (65 kg), it provides the sounding of air industrial pollutions at up to 20 km range in scanning sector 90{degree}. Power feed is less than 800 Wt. Lidar can be disposed as stationary so on the car, helicopter, light plane. Results of location of smoke tails and city smog in situ experiments are cited. Showed advantages of work of acquisition system in photon counting mode when dynamic range of a signal is up to six orders.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4885103','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4885103"><span id="translatedtitle"><span class="hlt">Aerosol</span> Transmission of Filoviruses</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mekibib, Berhanu; Ariën, Kevin K.</p> <p>2016-01-01</p> <p>Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013–2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of <span class="hlt">aerosol</span> transmission of filoviruses. PMID:27223296</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27223296','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27223296"><span id="translatedtitle"><span class="hlt">Aerosol</span> Transmission of Filoviruses.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mekibib, Berhanu; Ariën, Kevin K</p> <p>2016-01-01</p> <p>Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013-2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of <span class="hlt">aerosol</span> transmission of filoviruses. PMID:27223296</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACPD...15.7933P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACPD...15.7933P"><span id="translatedtitle">Utilization of O4 slant column density to derive <span class="hlt">aerosol</span> layer height from a spaceborne UV-visible hyperspectral sensor: sensitivity and case study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Park, S. S.; Kim, J.; Lee, H.; Torres, O.; Lee, K.-M.; Lee, S. D.</p> <p>2015-03-01</p> <p>The sensitivities of oxygen-dimer (O4) slant column densities (SCDs) to changes in <span class="hlt">aerosol</span> layer height are investigated using simulated radiances by a radiative transfer model, Linearized Discrete Ordinate Radiative Transfer (LIDORT), and Differential Optical Absorption Spectroscopy (DOAS) technique. The sensitivities of the O4 SCDs to <span class="hlt">aerosol</span> types and optical properties are also evaluated and compared. Among the O4 absorption bands at 340, 360, 380, and 477 nm, the O4 absorption band at 477 nm is found to be the most suitable to retrieve the <span class="hlt">aerosol</span> effective height. However, the O4 SCD at 477 nm is significantly influenced not only by the <span class="hlt">aerosol</span> layer effective height but also by <span class="hlt">aerosol</span> vertical profiles, optical properties including single scattering albedo (SSA), <span class="hlt">aerosol</span> optical depth (AOD), and surface albedo. Overall, the error of the retrieved <span class="hlt">aerosol</span> effective height is estimated to be 414 m (16.5%), 564 m (22.4%), and 1343 m (52.5%) for absorbing, dust, and non-absorbing <span class="hlt">aerosol</span>, respectively, assuming knowledge on the <span class="hlt">aerosol</span> vertical distribution type. Using radiance data from the Ozone Monitoring Instrument (OMI), a new algorithm is developed to derive the <span class="hlt">aerosol</span> effective height over East Asia after the determination of the <span class="hlt">aerosol</span> type and AOD from the MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS). The retrieved <span class="hlt">aerosol</span> effective heights are lower by approximately 300 m (27 %) compared to those obtained from the ground-based LIDAR measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/5007941','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/5007941"><span id="translatedtitle">Regional comparison of technetium-99m DTPA <span class="hlt">aerosol</span> and radioactive gas ventilation (xenon and krypton) studies in patients with suspected pulmonary embolism</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ramanna, L.; Alderson, P.O.; Waxman, A.D.; Berman, D.S.; Brachman, M.B.; Kroop, S.A.; Goldsmith, M.; Tanasescu, D.E.</p> <p>1986-09-01</p> <p>The regional distribution of (99mTc)DTPA <span class="hlt">aerosol</span> was compared with that of /sup 133/Xe (n = 30) and krypton (n = 24) in a group of patients with suspected pulmonary embolism. All patients had an <span class="hlt">aerosol</span> study using a recently available commercial generator system, a ventilation study with one of the gases, and perfusion <span class="hlt">imaging</span>. Regional information was assessed visually on xenon, krypton, and <span class="hlt">aerosol</span> studies independently by considering each lung as three equal-sized zones. In addition, gas ventilation findings peripheral to regions of <span class="hlt">aerosol</span> turbulence (hot spots) were evaluated. Only 64% of the zones were in complete agreement on xenon and <span class="hlt">aerosol</span>. Most of the discordance between xenon and <span class="hlt">aerosol</span> was accounted for by minor degrees of /sup 133/Xe washout retention in zones that appeared normal in the <span class="hlt">aerosol</span> study. An agreement rate of 85% was noted between 81mKr and <span class="hlt">aerosol</span> regionally. The regions of discordance between <span class="hlt">aerosol</span> and gas studies, however, usually were associated with unimpressive perfusion defects that did not change the scintigraphic probability for pulmonary embolism in any patient. Regarding zones of <span class="hlt">aerosol</span> hyperdeposition, 76% had associated washout abnormalities on xenon; however, there was no correlation between the presence of these abnormalities or perfusion abnormalities. The results confirm the high sensitivity of /sup 133/Xe washout <span class="hlt">imaging</span>, but suggest that radioaerosol <span class="hlt">imaging</span> will detect most parenchymal abnormalities associated with perfusion defects of significance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GMD.....9.2377W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GMD.....9.2377W"><span id="translatedtitle">Multi-sensor cloud and <span class="hlt">aerosol</span> retrieval simulator and remote sensing from model parameters - Part 2: <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wind, Galina; da Silva, Arlindo M.; Norris, Peter M.; Platnick, Steven; Mattoo, Shana; Levy, Robert C.</p> <p>2016-07-01</p> <p>The Multi-sensor Cloud Retrieval Simulator (MCRS) produces a "simulated radiance" product from any high-resolution general circulation model with interactive <span class="hlt">aerosol</span> as if a specific sensor such as the Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) were viewing a combination of the atmospheric column and land-ocean surface at a specific location. Previously the MCRS code only included contributions from atmosphere and clouds in its radiance calculations and did not incorporate properties of <span class="hlt">aerosols</span>. In this paper we added a new <span class="hlt">aerosol</span> properties module to the MCRS code that allows users to insert a mixture of up to 15 different <span class="hlt">aerosol</span> species in any of 36 vertical layers.This new MCRS code is now known as MCARS (Multi-sensor Cloud and <span class="hlt">Aerosol</span> Retrieval Simulator). Inclusion of an <span class="hlt">aerosol</span> module into MCARS not only allows for extensive, tightly controlled testing of various aspects of satellite operational cloud and <span class="hlt">aerosol</span> properties retrieval algorithms, but also provides a platform for comparing cloud and <span class="hlt">aerosol</span> models against satellite measurements. This kind of two-way platform can improve the efficacy of model parameterizations of measured satellite radiances, allowing the assessment of model skill consistently with the retrieval algorithm. The MCARS code provides dynamic controls for appearance of cloud and <span class="hlt">aerosol</span> layers. Thereby detailed quantitative studies of the impacts of various atmospheric components can be controlled.In this paper we illustrate the operation of MCARS by deriving simulated radiances from various data field output by the Goddard Earth Observing System version 5 (GEOS-5) model. The model <span class="hlt">aerosol</span> fields are prepared for translation to simulated radiance using the same model subgrid variability parameterizations as are used for cloud and atmospheric properties profiles, namely the ICA technique. After MCARS computes modeled sensor radiances equivalent to their observed counterparts, these radiances are presented as input to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmRe.171...31Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmRe.171...31Y"><span id="translatedtitle">A new method of satellite-based haze <span class="hlt">aerosol</span> monitoring over the North China Plain and a comparison with MODIS Collection 6 <span class="hlt">aerosol</span> products</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yan, Xing; Shi, Wenzhong; Luo, Nana; Zhao, Wenji</p> <p>2016-05-01</p> <p>With worldwide urbanization, hazy weather has been increasingly frequent, especially in the North China Plain. However, haze <span class="hlt">aerosol</span> monitoring remains a challenge. In this paper, MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) measurements were used to develop an enhanced haze <span class="hlt">aerosol</span> retrieval algorithm (EHARA). This method can work not only on hazy days but also on normal weather days. Based on 12-year (2002-2014) <span class="hlt">Aerosol</span> Robotic Network (AERONET) <span class="hlt">aerosol</span> property data, empirical single scattering albedo (SSA) and asymmetry factor (AF) values were chosen to assist haze <span class="hlt">aerosol</span> retrieval. For validation, EHARA <span class="hlt">aerosol</span> optical thickness (AOT) values, along with MODIS Collection 6 (C6) dark-pixel and deep blue <span class="hlt">aerosol</span> products, were compared with AERONET data. The results show that the EHARA can achieve greater AOT spatial coverage under hazy conditions with a high accuracy (73% within error range) and work a higher resolution (1-km). Additionally, this paper presents a comprehensive discussion of the differences between and limitations of the EHARA and the MODIS C6 DT land algorithms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRD..112.2206D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRD..112.2206D"><span id="translatedtitle">Analysis of reflectance spectra of UV-absorbing <span class="hlt">aerosol</span> scenes measured by SCIAMACHY</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Graaf, M.; Stammes, P.; Aben, E. A. A.</p> <p>2007-01-01</p> <p>Reflectance spectra from 280-1750 nm of typical desert dust <span class="hlt">aerosol</span> (DDA) and biomass burning <span class="hlt">aerosol</span> (BBA) scenes over oceans are presented, measured by the space-borne spectrometer Scanning <span class="hlt">Imaging</span> Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY). DDA and BBA are both UV-absorbing <span class="hlt">aerosols</span>, but their effect on the top-of-atmosphere (TOA) reflectance is different due to differences in the way mineral <span class="hlt">aerosols</span> and smoke reflect and absorb radiation. Mineral <span class="hlt">aerosols</span> are typically large, inert particles, found in warm, dry continental air. Smoke particles, on the other hand, are usually small particles, although often clustered, chemically very active and highly variable in composition. Moreover, BBA are hygroscopic and over oceans BBA were invariably found in cloudy scenes. TOA reflectance spectra of typical DDA and BBA scenes were analyzed, using radiative transfer simulations, and compared. The DDA spectrum was successfully simulated using a layer with a bimodal size distribution of mineral <span class="hlt">aerosols</span> in a clear sky. The spectrum of the BBA scene, however, was determined by the interaction between cloud droplets and smoke particles, as is shown by simulations with a model of separate <span class="hlt">aerosol</span> and cloud layers and models with internally and externally mixed <span class="hlt">aerosol</span>/cloud layers. The occurrence of clouds in smoke scenes when sufficient water vapor is present usually prevents the detection of optical properties of these <span class="hlt">aerosol</span> plumes using space-borne sensors. However, the Absorbing <span class="hlt">Aerosol</span> Index (AAI), a UV color index, is not sensitive to scattering <span class="hlt">aerosols</span> and clouds and can be used to detect these otherwise obscured <span class="hlt">aerosol</span> plumes over clouds. The amount of absorption of radiation can be expressed using the absorption optical thickness. The absorption optical thickness in the DDA case was 0.42 (340 nm) and 0.14 (550 nm) for an <span class="hlt">aerosol</span> layer of optical thickness 1.74 (550 nm). In the BBA case the absorption optical thickness was 0.18 (340 nm) and 0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=dolphin+AND+language&pg=2&id=ED287161','ERIC'); return false;" href="http://eric.ed.gov/?q=dolphin+AND+language&pg=2&id=ED287161"><span id="translatedtitle">Cost-Benefit Analysis for ECIA Chapter 1 and State DPPF Programs Comparing Groups Receiving Regular Program Instruction and Groups Receiving Computer Assisted Instruction/Computer Management System (<span class="hlt">CAI</span>/CMS). 1986-87.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Chamberlain, Ed</p> <p></p> <p>A cost benefit study was conducted to determine the effectiveness of a computer assisted instruction/computer management system (<span class="hlt">CAI</span>/CMS) as an alternative to conventional methods of teaching reading within Chapter 1 and DPPF funded programs of the Columbus (Ohio) Public Schools. The Chapter 1 funded Compensatory Language Experiences and Reading…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910018326','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910018326"><span id="translatedtitle">Background stratospheric <span class="hlt">aerosol</span> reference model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccormick, M. P.; Wang, P.</p> <p>1989-01-01</p> <p>In this analysis, a reference background stratospheric <span class="hlt">aerosol</span> optical model is developed based on the nearly global SAGE 1 satellite observations in the non-volcanic period from March 1979 to February 1980. Zonally averaged profiles of the 1.0 micron <span class="hlt">aerosol</span> extinction for the tropics and the mid- and high-altitudes for both hemispheres are obtained and presented in graphical and tabulated form for the different seasons. In addition, analytic expressions for these seasonal global zonal means, as well as the yearly global mean, are determined according to a third order polynomial fit to the vertical profile data set. This proposed background stratospheric <span class="hlt">aerosol</span> model can be useful in modeling studies of stratospheric <span class="hlt">aerosols</span> and for simulations of atmospheric radiative transfer and radiance calculations in atmospheric remote sensing.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3023421','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3023421"><span id="translatedtitle">Mycobacterial <span class="hlt">Aerosols</span> and Respiratory Disease</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2003-01-01</p> <p>Environmental opportunistic mycobacteria, including Mycobacterium avium, M. terrae, and the new species M. immunogenum, have been implicated in outbreaks of hypersensitivity pneumonitis or respiratory problems in a wide variety of settings. One common feature of the outbreaks has been exposure to <span class="hlt">aerosols</span>. <span class="hlt">Aerosols</span> have been generated from metalworking fluid during machining and grinding operations as well as from indoor swimming pools, hot tubs, and water-damaged buildings. Environmental opportunistic mycobacteria are present in drinking water, resistant to disinfection, able to provoke inflammatory reactions, and readily <span class="hlt">aerosolized</span>. In all outbreaks, the water sources of the <span class="hlt">aerosols</span> were disinfected. Disinfection may select for the predominance and growth of mycobacteria. Therefore, mycobacteria may be responsible, in part, for many outbreaks of hypersensitivity pneumonitis and other respiratory problems in the workplace and home. PMID:12890314</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19760087420&hterms=climatic+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dclimatic%2Bchange','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19760087420&hterms=climatic+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dclimatic%2Bchange"><span id="translatedtitle">Stratospheric <span class="hlt">aerosols</span> and climatic change</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Baldwin, B.; Pollack, J. B.; Summers, A.; Toon, O. B.; Sagan, C.; Van Camp, W.</p> <p>1976-01-01</p> <p>Generated primarily by volcanic explosions, a layer of submicron silicate particles and particles made of concentrated sulfuric acids solution is present in the stratosphere. Flights through the stratosphere may be a future source of stratospheric <span class="hlt">aerosols</span>, since the effluent from supersonic transports contains sulfurous gases (which will be converted to H2SO4) while the exhaust from Space Shuttles contains tiny aluminum oxide particles. Global heat balance calculations have shown that the stratospheric <span class="hlt">aerosols</span> have made important contributions to some climatic changes. In the present paper, accurate radiative transfer calculations of the globally-averaged surface temperature (T) are carried out to estimate the sensitivity of the climate to changes in the number of stratospheric <span class="hlt">aerosols</span>. The results obtained for a specified model atmosphere, including a vertical profile of the <span class="hlt">aerosols</span>, indicate that the climate is unlikely to be affected by supersonic transports and Space Shuttles, during the next decades.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810023137','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810023137"><span id="translatedtitle">Satellite measurements of tropospheric <span class="hlt">aerosols</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Griggs, M.</p> <p>1981-01-01</p> <p>This investigation uses LANDSAT 2 radiance data and ground-truth measurements of the <span class="hlt">aerosol</span> optical thickness, obtained previously from five inland sites, to study the usefulness and limitations of the near infrared radiance over inland bodies of water. The linear relationship between LANDSAT 2 MSS7 and <span class="hlt">aerosol</span> content found in this study can be used to estimate the <span class="hlt">aerosol</span> content with a standard deviation of 0.42N. Analysis of the data for MSS6 and MSS7 suggest that the larger uncertainty is mostly due to water turbidity, with little contribution from the adjacency effect. The relationship found is best applied to determine an average <span class="hlt">aerosol</span> content over a period of time at a given target, or an area average at a given time over several targets close together.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/861062','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/861062"><span id="translatedtitle"><span class="hlt">AEROSOL</span>, CLOUDS, AND CLIMATE CHANGE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>SCHWARTZ, S.E.</p> <p>2005-09-01</p> <p>Earth's climate is thought to be quite sensitive to changes in radiative fluxes that are quite small in absolute magnitude, a few watts per square meter, and in relation to these fluxes in the natural climate. Atmospheric <span class="hlt">aerosol</span> particles exert influence on climate directly, by scattering and absorbing radiation, and indirectly by modifying the microphysical properties of clouds and in turn their radiative effects and hydrology. The forcing of climate change by these indirect effects is thought to be quite substantial relative to forcing by incremental concentrations of greenhouse gases, but highly uncertain. Quantification of <span class="hlt">aerosol</span> indirect forcing by satellite- or ground-based remote sensing has proved quite difficult in view of inherent large variation in the pertinent observables such as cloud optical depth, which is controlled mainly by liquid water path and only secondarily by <span class="hlt">aerosols</span>. Limited work has shown instances of large magnitude of <span class="hlt">aerosol</span> indirect forcing, with local instantaneous forcing upwards of 50 W m{sup 66}-2. Ultimately it will be necessary to represent <span class="hlt">aerosol</span> indirect effects in climate models to accurately identify the anthropogenic forcing at present and over secular time and to assess the influence of this forcing in the context of other forcings of climate change. While the elements of <span class="hlt">aerosol</span> processes that must be represented in models describing the evolution and properties of <span class="hlt">aerosol</span> particles that serve as cloud condensation particles are known, many important components of these processes remain to be understood and to be represented in models, and the models evaluated against observation, before such model-based representations can confidently be used to represent <span class="hlt">aerosol</span> indirect effects in climate models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/867559','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/867559"><span id="translatedtitle">Method for producing monodisperse <span class="hlt">aerosols</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ortiz, Lawrence W.; Soderholm, Sidney C.</p> <p>1990-01-01</p> <p>An <span class="hlt">aerosol</span> generator is described which is capable of producing a monodisperse <span class="hlt">aerosol</span> within narrow limits utilizing an aqueous solution capable of providing a high population of seed nuclei and an organic solution having a low vapor pressure. The two solutions are cold nebulized, mixed, vaporized, and cooled. During cooling, particles of the organic vapor condense onto the excess seed nuclei, and grow to a uniform particle size.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20020064477&hterms=Seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DSeasons','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20020064477&hterms=Seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DSeasons"><span id="translatedtitle">Coordinated Airborne, Spaceborne, and Ground-Based Measurements of Massive, Thick <span class="hlt">Aerosol</span> Layers During the Dry Season in Southern Africa</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schmid, B.; Redemann, J.; Russell, P. B.; Hobbs, P. V.; Hlavka, D. L.; McGill, M. J.; Holben, B. N.; Welton, E. J.; Campbell, J.; Torres, O.; Hipskind, R. Stephen (Technical Monitor)</p> <p>2002-01-01</p> <p>During the dry-season airborne campaign of the Southern African Regional Science Initiative (SAFARI 2000), unique coordinated observations were made of massive, thick <span class="hlt">aerosol</span> layers. These layers were often dominated by <span class="hlt">aerosols</span> from biomass burning. We report on airborne Sunphotometer measurements of <span class="hlt">aerosol</span> optical depth (lambda=354-1558 nm), columnar water vapor, and vertical profiles of <span class="hlt">aerosol</span> extinction and water vapor density that were obtained aboard the University of Washington's Convair-580 research aircraft. We compare these with ground-based AERONET Sun/sky radiometer results, with ground based lidar data MPL-Net), and with measurements from a downward-pointing lidar aboard the high-flying NASA ER-2 aircraft. Finally, we show comparisons between <span class="hlt">aerosol</span> optical depths from the Sunphotometer and those retrieved over land and over water using four spaceborne sensors (TOMS (Total Ozone Mapping Spectrometer), MODIS (Moderate Resolution <span class="hlt">Imaging</span> Spectrometer), MISR (Multiangle <span class="hlt">Imaging</span> Spectroradiometer) and ATSR-2 (Along Track Scanning Radiometer)).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20160005005&hterms=imaging+polarimeter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dimaging%2Bpolarimeter','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20160005005&hterms=imaging+polarimeter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dimaging%2Bpolarimeter"><span id="translatedtitle">Space-Based Remote Sensing of Atmospheric <span class="hlt">Aerosols</span>: The Multi-Angle Spectro-Polarimetric Frontier</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kokhanovsky, A. A.; Davis, A. B.; Cairns, B.; Dubovik, O.; Hasekamp, O. P.; Sano, I.; Mukai, S.; Rozanov, V. V.; Litvinov, P.; Lapyonok, T.; Martin, W.; Wasilewski, A.; Xu, F.; Natraj, V.</p> <p>2015-01-01</p> <p>The review of optical instrumentation, forward modeling, and inverse problem solution for the polarimetric <span class="hlt">aerosol</span> remote sensing from space is presented. The special emphasis is given to the description of current airborne and satellite <span class="hlt">imaging</span> polarimeters and also to modern satellite <span class="hlt">aerosol</span> retrieval algorithms based on the measurements of the Stokes vector of reflected solar light as detected on a satellite. Various underlying surface reflectance models are discussed and evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140012646','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140012646"><span id="translatedtitle">Application of Spectral Analysis Techniques in the Intercomparison of <span class="hlt">Aerosol</span> Data: Part III. Using Combined PCA to Compare Spatiotemporal Variability of MODIS, MISR and OMI <span class="hlt">Aerosol</span> Optical Depth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Li, Jing; Carlson, Barbara E.; Lacis, Andrew A.</p> <p>2014-01-01</p> <p>Satellite measurements of global <span class="hlt">aerosol</span> properties are very useful in constraining <span class="hlt">aerosol</span> parameterization in climate models. The reliability of different data sets in representing global and regional <span class="hlt">aerosol</span> variability becomes an essential question. In this study, we present the results of a comparison using combined principal component analysis (CPCA), applied to monthly mean, mapped (Level 3) <span class="hlt">aerosol</span> optical depth (AOD) product from Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), Multiangle <span class="hlt">Imaging</span> Spectroradiometer (MISR), and Ozone Monitoring Instrument (OMI). This technique effectively finds the common space-time variability in the multiple data sets by decomposing the combined AOD field. The results suggest that all of the sensors capture the globally important <span class="hlt">aerosol</span> regimes, including dust, biomass burning, pollution, and mixed <span class="hlt">aerosol</span> types. Nonetheless, differences are also noted. Specifically, compared with MISR and OMI, MODIS variability is significantly higher over South America, India, and the Sahel. MODIS deep blue AOD has a lower seasonal variability in North Africa, accompanied by a decreasing trend that is not found in either MISR or OMI AOD data. The narrow swath of MISR results in an underestimation of dust variability over the Taklamakan Desert. The MISR AOD data also exhibit overall lower variability in South America and the Sahel. OMI does not capture the Russian wild fire in 2010 nor the phase shift in biomass burning over East South America compared to Central South America, likely due to cloud contamination and the OMI row anomaly. OMI also indicates a much stronger (boreal) winter peak in South Africa compared with MODIS and MISR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRD..119.4017L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRD..119.4017L"><span id="translatedtitle">Application of spectral analysis techniques in the intercomparison of <span class="hlt">aerosol</span> data: Part III. Using combined PCA to compare spatiotemporal variability of MODIS, MISR, and OMI <span class="hlt">aerosol</span> optical depth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Jing; Carlson, Barbara E.; Lacis, Andrew A.</p> <p>2014-04-01</p> <p>Satellite measurements of global <span class="hlt">aerosol</span> properties are very useful in constraining <span class="hlt">aerosol</span> parameterization in climate models. The reliability of different data sets in representing global and regional <span class="hlt">aerosol</span> variability becomes an essential question. In this study, we present the results of a comparison using combined principal component analysis (CPCA), applied to monthly mean, mapped (Level 3) <span class="hlt">aerosol</span> optical depth (AOD) product from Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS), Multiangle <span class="hlt">Imaging</span> Spectroradiometer (MISR), and Ozone Monitoring Instrument (OMI). This technique effectively finds the common space-time variability in the multiple data sets by decomposing the combined AOD field. The results suggest that all of the sensors capture the globally important <span class="hlt">aerosol</span> regimes, including dust, biomass burning, pollution, and mixed <span class="hlt">aerosol</span> types. Nonetheless, differences are also noted. Specifically, compared with MISR and OMI, MODIS variability is significantly higher over South America, India, and the Sahel. MODIS deep blue AOD has a lower seasonal variability in North Africa, accompanied by a decreasing trend that is not found in either MISR or OMI AOD data. The narrow swath of MISR results in an underestimation of dust variability over the Taklamakan Desert. The MISR AOD data also exhibit overall lower variability in South America and the Sahel. OMI does not capture the Russian wild fire in 2010 nor the phase shift in biomass burning over East South America compared to Central South America, likely due to cloud contamination and the OMI row anomaly. OMI also indicates a much stronger (boreal) winter peak in South Africa compared with MODIS and MISR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSM.A54B..04B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSM.A54B..04B"><span id="translatedtitle">Effect of <span class="hlt">Aerosols</span> on Surface Radiation and Air Quality in the Central American Region Estimated Using Satellite UV Instruments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhartia, P. K.; Torres, O.; Krotkov, N. A.</p> <p>2007-05-01</p> <p>Solar radiation reaching the Earth's surface is reduced by both <span class="hlt">aerosol</span> scattering and <span class="hlt">aerosol</span> absorption. Over many parts of the world the latter effect can be as large or larger than the former effect, and small changes in the <span class="hlt">aerosol</span> single scattering albedo can either cancel the former effect or enhance it. In addition, absorbing <span class="hlt">aerosols</span> embedded in clouds can greatly reduce the amount of radiation reaching the surface by multiple scattering. Though the potential climatic effects of absorbing <span class="hlt">aerosols</span> have received considerable attention lately, their effect on surface UV, photosynthesis, and photochemistry can be equally important for our environment and may affect human health and agricultural productivity. Absorption of all <span class="hlt">aerosols</span> commonly found in the Earth's atmosphere becomes larger in the UV and blue wavelengths and has a relatively strong wavelength dependence. This is particularly true of mineral dust and organic <span class="hlt">aerosols</span>. However, these effects have been very difficult to estimate on a global basis since the satellite instruments that operate in the visible are primarily sensitive to <span class="hlt">aerosol</span> scattering. A notable exception is the UV <span class="hlt">Aerosol</span> Index (AI), first produced using NASA's Nimbus-7 TOMS data. AI provides a direct measure of the effect of <span class="hlt">aerosol</span> absorption on the backscattered UV radiation in both clear and cloudy conditions, as well as over snow/ice. Although many types of <span class="hlt">aerosols</span> produce a distinct color cast in the visible <span class="hlt">images</span>, and <span class="hlt">aerosols</span> absorption over clouds and snow/ice could, in principle be detected from their color, so far this technique has worked well only in the UV. In this talk we will discuss what we have learned from the long-term record of AI produced from TOMS and Aura/OMI about the possible role of <span class="hlt">aerosols</span> on surface radiation and air quality in the Central American region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20110016153&hterms=right+view&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dright%2Bview','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20110016153&hterms=right+view&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dright%2Bview"><span id="translatedtitle">Global View of <span class="hlt">Aerosol</span> Vertical Distributions from CALIPSO Lidar Measurements and GOCART Simulations: Regional and Seasonal Variations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Yu, Hongbin; Chin, Mian; Winker, David M.; Omar, Ali H.; Liu, Zhaoyan; Kittaka, Chieko; Diehl, Thomas</p> <p>2010-01-01</p> <p>This study examines seasonal variations of the vertical distribution of <span class="hlt">aerosols</span> through a statistical analysis of the Cloud-<span class="hlt">Aerosol</span> Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) lidar observations from June 2006 to November 2007. A data-screening scheme is developed to attain good quality data in cloud-free conditions, and the polarization measurement is used to separate dust from non-dust <span class="hlt">aerosol</span>. The CALIPSO <span class="hlt">aerosol</span> observations are compared with <span class="hlt">aerosol</span> simulations from the Goddard Chemistry <span class="hlt">Aerosol</span> Radiation Transport (GOCART) model and <span class="hlt">aerosol</span> optical depth (AOD) measurements from the MODerate resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS). The CALIPSO observations of geographical patterns and seasonal variations of AOD are generally consistent with GOCART simulations and MODIS retrievals especially near source regions, while the magnitude of AOD shows large discrepancies in most regions. Both the CALIPSO observation and GOCART model show that the <span class="hlt">aerosol</span> extinction scale heights in major dust and smoke source regions are generally higher than that in industrial pollution source regions. The CALIPSO <span class="hlt">aerosol</span> lidar ratio also generally agrees with GOCART model within 30% on regional scales. Major differences between satellite observations and GOCART model are identified, including (1) an underestimate of <span class="hlt">aerosol</span> extinction by GOCART over the Indian sub-continent, (2) much larger <span class="hlt">aerosol</span> extinction calculated by GOCART than observed by CALIPSO in dust source regions, (3) much weaker in magnitude and more concentrated <span class="hlt">aerosol</span> in the lower atmosphere in CALIPSO observation than GOCART model over transported areas in midlatitudes, and (4) consistently lower <span class="hlt">aerosol</span> scale height by CALIPSO observation than GOCART model. Possible factors contributing to these differences are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130013402','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130013402"><span id="translatedtitle">Satellite Remote Sensing: <span class="hlt">Aerosol</span> Measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kahn, Ralph A.</p> <p>2013-01-01</p> <p><span class="hlt">Aerosols</span> are solid or liquid particles suspended in the air, and those observed by satellite remote sensing are typically between about 0.05 and 10 microns in size. (Note that in traditional <span class="hlt">aerosol</span> science, the term "<span class="hlt">aerosol</span>" refers to both the particles and the medium in which they reside, whereas for remote sensing, the term commonly refers to the particles only. In this article, we adopt the remote-sensing definition.) They originate from a great diversity of sources, such as wildfires, volcanoes, soils and desert sands, breaking waves, natural biological activity, agricultural burning, cement production, and fossil fuel combustion. They typically remain in the atmosphere from several days to a week or more, and some travel great distances before returning to Earth's surface via gravitational settling or washout by precipitation. Many <span class="hlt">aerosol</span> sources exhibit strong seasonal variability, and most experience inter-annual fluctuations. As such, the frequent, global coverage that space-based <span class="hlt">aerosol</span> remote-sensing instruments can provide is making increasingly important contributions to regional and larger-scale <span class="hlt">aerosol</span> studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17842894','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17842894"><span id="translatedtitle">Climate forcing by anthropogenic <span class="hlt">aerosols</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Charlson, R J; Schwartz, S E; Hales, J M; Cess, R D; Coakley, J A; Hansen, J E; Hofmann, D J</p> <p>1992-01-24</p> <p>Although long considered to be of marginal importance to global climate change, tropospheric <span class="hlt">aerosol</span> contributes substantially to radiative forcing, and anthropogenic sulfate <span class="hlt">aerosol</span> in particular has imposed a major perturbation to this forcing. Both the direct scattering of shortwavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate <span class="hlt">aerosol</span> particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square meter, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the <span class="hlt">aerosol</span> forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. <span class="hlt">Aerosol</span> effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of <span class="hlt">aerosol</span> climate forcing and on the controlling chemical and physical processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992Sci...255..423C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992Sci...255..423C"><span id="translatedtitle">Climate Forcing by Anthropogenic <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Charlson, R. J.; Schwartz, S. E.; Hales, J. M.; Cess, R. D.; Coakley, J. A., Jr.; Hansen, J. E.; Hofmann, D. J.</p> <p>1992-01-01</p> <p>Although long considered to be of marginal importance to global climate change, tropospheric <span class="hlt">aerosol</span> contributes substantially to radiative forcing, and anthropogenic sulfate <span class="hlt">aerosol</span> in particular has imposed a major perturbation to this forcing. Both the direct scattering of short-wavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate <span class="hlt">aerosol</span> particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square meter, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the <span class="hlt">aerosol</span> forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. <span class="hlt">Aerosol</span> effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of <span class="hlt">aerosol</span> climate forcing and on the controlling chemical and physical processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20050156628&hterms=remote+work&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dremote%2Bwork','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20050156628&hterms=remote+work&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dremote%2Bwork"><span id="translatedtitle">Passive Remote Sensing of <span class="hlt">Aerosols</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>King, Michael D.</p> <p>2005-01-01</p> <p>Remote sensing of <span class="hlt">aerosol</span> optical and microphysical properties got a resurgence in the 1970s when John Reagan and Ben Herman initiated a program to develop and implement a surface-based sunphotometer system to monitor spectral <span class="hlt">aerosol</span> optical thickness at the University of Arizona. In this presentation I will review the state of the technology used to monitor <span class="hlt">aerosol</span> optical and microphysical properties, including the determination of spectral <span class="hlt">aerosol</span> optical thickness and total ozone content. This work continued with John Reagan developed a surface-based spectral flux radiometer to implement Ben Herman's idea to determine the imaginary part of the complex refractive index of <span class="hlt">aerosols</span> using the recently developed diffuse-direct technique. Progress made both in surface-based instrumentation, inversion theory for analyzing such data, and in satellite observations of <span class="hlt">aerosol</span> optical and microphysical properties will be reviewed to highlight the state of knowledge after 30 years of expanded capability and introduction of novel new capabilities, both from the ground and from spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19920039724&hterms=greenhouse+gases+climate+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dgreenhouse%2Bgases%2Bclimate%2Bchange','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19920039724&hterms=greenhouse+gases+climate+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dgreenhouse%2Bgases%2Bclimate%2Bchange"><span id="translatedtitle">Climate forcing by anthropogenic <span class="hlt">aerosols</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Charlson, R. J.; Schwartz, S. E.; Hales, J. M.; Cess, R. D.; Coakley, J. A., Jr.; Hansen, J. E.; Hofmann, D. J.</p> <p>1992-01-01</p> <p>Although long considered to be of marginal importance to global climate change, tropospheric <span class="hlt">aerosol</span> contributes substantially to radiative forcing, and anthropogenic sulfate <span class="hlt">aerosol</span>, in particular, has imposed a major perturbation to this forcing. Both the direct scattering of short-wavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate <span class="hlt">aerosol</span> particles increase planetary albedo, thereby exerting a cooling influence on the planet. Current climate forcing due to anthropogenic sulfate is estimated to be -1 to -2 watts per square meter, globally averaged. This perturbation is comparable in magnitude to current anthropogenic greenhouse gas forcing but opposite in sign. Thus, the <span class="hlt">aerosol</span> forcing has likely offset global greenhouse warming to a substantial degree. However, differences in geographical and seasonal distributions of these forcings preclude any simple compensation. <span class="hlt">Aerosol</span> effects must be taken into account in evaluating anthropogenic influences on past, current, and projected future climate and in formulating policy regarding controls on emission of greenhouse gases and sulfur dioxide. Resolution of such policy issues requires integrated research on the magnitude and geographical distribution of <span class="hlt">aerosol</span> climate forcing and on the controlling chemical and physical processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JGRD..113.7206L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JGRD..113.7206L"><span id="translatedtitle">Synthesis of information on <span class="hlt">aerosol</span> optical properties</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Hongqing; Pinker, R. T.; Chin, M.; Holben, B.; Remer, L.</p> <p>2008-04-01</p> <p>In a previous study (Liu et al., 2005) obtained are global scale estimates of <span class="hlt">aerosol</span> optical depth at 0.55 μm based on spatial and temporal variation patterns from models and satellite observations, regulated by the <span class="hlt">Aerosol</span> Robotic Network (AERONET) measurements. In this study an approach is developed to obtain information on global distribution of the single scattering albedo (ω0), the asymmetry parameter (g), and the normalized extinction coefficient over shortwave (SW) spectrum. Since space observations of ω0 are in early stages of development and none are available for g, first an approach was developed to infer them from relevant information from the Global Ozone Chemistry <span class="hlt">Aerosol</span> Radiation and Transport (GOCART) model, Moderate Resolution <span class="hlt">Imaging</span> Spectroradiometer (MODIS) and AERONET retrievals. The single scattering albedo is generated by extending GOCART ω0 at 0.55 μm to the entire SW spectrum using spectral dependence derived from AERONET retrievals. The asymmetry parameter over the solar spectrum is derived from the MODIS Ångström wavelength exponent, utilizing a relationship based on AERONET almucantar observations. The normalized extinction coefficient is estimated from the MODIS Ångström wavelength exponent. The methodology was implemented as a "proof of concept" with one year of data. The approach described here is a step in preparedness for utilizing information from new observing systems (e.g., MISR, A-Train constellation) when available. The impact of the newly derived information on the quality of satellite based estimates of surface radiative fluxes was evaluated and is presented by Liu and Pinker (2008).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20160011400&hterms=Ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DOcean','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20160011400&hterms=Ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DOcean"><span id="translatedtitle">The Role of Cloud Contamination, <span class="hlt">Aerosol</span> Layer Height and <span class="hlt">Aerosol</span> Model in the Assessment of the OMI Near-UV Retrievals Over the Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gasso, Santiago; Torres, Omar</p> <p>2016-01-01</p> <p>Retrievals of <span class="hlt">aerosol</span> optical depth (AOD) at 388 nm over the ocean from the Ozone Monitoring Instrument (OMI) two-channel near-UV algorithm (OMAERUV) have been compared with independent AOD measurements. The analysis was carried out over the open ocean (OMI and MODerate-resolution <span class="hlt">Imaging</span> Spectrometer (MODIS) AOD comparisons) and over coastal and island sites (OMI and AERONET, the <span class="hlt">AErosol</span> RObotic NETwork). Additionally, a research version of the retrieval algorithm (using MODIS and CALIOP (Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization) information as constraints) was utilized to evaluate the sensitivity of the retrieval to different assumed <span class="hlt">aerosol</span> properties. Overall, the comparison resulted in differences (OMI minus independent measurements) within the expected levels of uncertainty for the OMI AOD retrievals (0.1 for AOD less than 0.3, 30% for AOD greater than 0.3). Using examples from case studies with outliers, the reasons that led to the observed differences were examined with specific purpose to determine whether they are related to instrument limitations (i.e., pixel size, calibration) or algorithm assumptions (such as <span class="hlt">aerosol</span> shape, <span class="hlt">aerosol</span> height). The analysis confirms that OMAERUV does an adequate job at rejecting cloudy scenes within the instrument's capabilities. There is a residual cloud contamination in OMI pixels with quality flag 0 (the best conditions for <span class="hlt">aerosol</span> retrieval according to the algorithm), resulting in a bias towards high AODs in OMAERUV. This bias is more pronounced at low concentrations of absorbing <span class="hlt">aerosols</span> (AOD 388 nm approximately less than 0.5). For higher <span class="hlt">aerosol</span> loadings, the bias remains within OMI's AOD uncertainties. In pixels where OMAERUV assigned a dust <span class="hlt">aerosol</span> model, a fraction of them (less than 20 %) had retrieved AODs significantly lower than AERONET and MODIS AODs. In a case study, a detailed examination of the <span class="hlt">aerosol</span> height from CALIOP and the AODs from MODIS, along with sensitivity tests, was carried out by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AMT.....9.3031G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AMT.....9.3031G"><span id="translatedtitle">The role of cloud contamination, <span class="hlt">aerosol</span> layer height and <span class="hlt">aerosol</span> model in the assessment of the OMI near-UV retrievals over the ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gassó, Santiago; Torres, Omar</p> <p>2016-07-01</p> <p>Retrievals of <span class="hlt">aerosol</span> optical depth (AOD) at 388 nm over the ocean from the Ozone Monitoring Instrument (OMI) two-channel near-UV algorithm (OMAERUV) have been compared with independent AOD measurements. The analysis was carried out over the open ocean (OMI and MODerate-resolution <span class="hlt">Imaging</span> Spectrometer (MODIS) AOD comparisons) and over coastal and island sites (OMI and AERONET, the <span class="hlt">AErosol</span> RObotic NETwork). Additionally, a research version of the retrieval algorithm (using MODIS and CALIOP (Cloud-<span class="hlt">Aerosol</span> Lidar with Orthogonal Polarization) information as constraints) was utilized to evaluate the sensitivity of the retrieval to different assumed <span class="hlt">aerosol</span> properties. Overall, the comparison resulted in differences (OMI minus independent measurements) within the expected levels of uncertainty for the OMI AOD retrievals (0.1 for AOD < 0.3, 30 % for AOD > 0.3). Using examples from case studies with outliers, the reasons that led to the observed differences were examined with specific purpose to determine whether they are related to instrument limitations (i.e., pixel size, calibration) or algorithm assumptions (such as <span class="hlt">aerosol</span> shape, <span class="hlt">aerosol</span> height). The analysis confirms that OMAERUV does an adequate job at rejecting cloudy scenes within the instrument's capabilities. There is a residual cloud contamination in OMI pixels with quality flag 0 (the best conditions for <span class="hlt">aerosol</span> retrieval according to the algorithm), resulting in a bias towards high AODs in OMAERUV. This bias is more pronounced at low concentrations of absorbing <span class="hlt">aerosols</span> (AOD 388 nm ˜ < 0.5). For higher <span class="hlt">aerosol</span> loadings, the bias remains within OMI's AOD uncertainties. In pixels where OMAERUV assigned a dust <span class="hlt">aerosol</span> model, a fraction of them (< 20 %) had retrieved AODs significantly lower than AERONET and MODIS AODs. In a case study, a detailed examination of the <span class="hlt">aerosol</span> height from CALIOP and the AODs from MODIS, along with sensitivity tests, was carried out by varying the different assumed parameters in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815690W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815690W"><span id="translatedtitle">Holistic <span class="hlt">aerosol</span> evaluation using s