The frequency distribution of daily global irradiation at Kumasi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akuffo, F.O.; Brew-Hammond, A.

1993-02-01

Cumulative frequency distribution curves (CDC) for daily global irradiation on the horizontal produced by Liu and Jordan in 1963 have until recently been considered to have universal validity. Results obtained by Saunier et al. in 1987 and Ideriah and Suleman in 1989 for two tropical locations, Ibadan in Nigeria and Bangkok in Thailand, respectively, have thrown into question the universal validity of the Liu and Jordan generalized CDC. Saunier et al., in particular, showed that their results disagreed with the generalized CDC mainly because of differences in the values of the maximum clearness index (Kmax), as well as the underlyingmore » probability density functions. Consequently, they proposed two expressions for determining Kmax and probability densities in tropical locations. This paper presents the results of statistical analysis of daily global irradiation for Kumasi, Ghana, also a tropical location. The results show that the expressions of Saunier et al. provide a better description of the observations than the generalized CDC and, in particular, the empirical equation for Kmax may be valid for Kumasi. Furthermore, the results show that the values of the minimum clearness index (Kmin) for Kumasi are much higher than the generally accepted value of 0.05 for overcast sky conditions. A comparison of the results for Kumasi and Ibadan shows that there is satisfactory agreement when the values of Kmax and Kmin are comparable; in cases where there are discrepancies in the Kmax and Kmin values, the CDC also disagree. 13 refs., 3 figs., 5 tabs.« less

Global Mapping of Underwater UV Irradiances and DNA-Weighted Exposures using TOMS and SeaWiFS Data Products

NASA Technical Reports Server (NTRS)

Vasilkov, Alexander; Krotkov, Nickolay; Herman, Jay; McClain, Charles; Arrigo, Kevin; Robinson, Wayne

1999-01-01

The global stratospheric ozone-layer depletion results In an increase in biologically harmful ultraviolet (UV) radiation reaching the surface and penetrating to ecologically significant depths in natural waters. Such an increase can be estimated on a global scale by combining satellite estimates of UV irradiance at the ocean surface from the Total Ozone Mapping Spectrometer (TOMS) satellite instrument with the SeaWIFS satellite ocean-color measurements in the visible spectral region. In this paper we propose a model of seawater optical properties in the UV spectral region based on the Case I water model in the visible range. The inputs to the model are standard monthly SeaWiFS products: chlorophyll concentration and the diffuse attenuation coefficient at 490nm. Penetration of solar UV radiation to different depths in open ocean waters is calculated using the RT (radiative transfer) quasi-single scattering approximation (QSSA). The accuracy of the QSSA approximation in the water is tested using more accurate codes. The sensitivity study of the underwater UV irradiance to atmospheric and oceanic optical properties have shown that the main environmental parameters controlling the absolute levels of the UVB (280-320nm) and DNA-weighted irradiance underwater are: solar-zenith angle, cloud transmittance, water optical properties, and total ozone. Weekly maps of underwater UV irradiance and DNA-weighted exposure are calculated using monthly-mean SeaWiFS chlorophyll and diffuse attenuation coefficient products, daily SeaWiFS cloud fraction data, and the TOMS-derived surface UV irradiance daily maps. The final products include global maps of weekly-average UVB irradiance and DNA-weighted daily exposures at 3m and 10m, and depths where the UVB irradiance and DNA-weighted dose rate at local noon are equal to 10% of their surface values.

Empirical evaluation of global vitamin D effective ultraviolet irradiances under cloudy conditions for a subtropical southern hemisphere site.

PubMed

Turnbull, David J; Parisi, Alfio V; Schouten, Peter W

2010-05-01

This paper evaluates the global vitamin D effective UV (UV(vitd)) irradiances under cloudy conditions at a subtropical, southern hemisphere site. The UV(vitd) irradiances were analyzed on a horizontal plane and sampled at 5-min intervals over 18 months so that a wide range of parameters including cloud conditions, solar zenith angles (SZA) and ozone levels were taken into account. Cloud modification factors were determined from the influence of clouds on the global broadband solar radiation, and these were applied to the cloud-free vitamin D effective UV irradiance to evaluate the UV(vitd) irradiances on a horizontal plane for cloudy conditions. For vitamin D effective UV irradiance, cloud modification factors were found to range from 0.9 to 1.0 for no cloud and 0.4 to 0.5 for 8 octa of cloud cover. SZA played a minimal role in this variation. A comparison of the measured and calculated UV(vitd) irradiances for the 2004 data set in the range of SZA of 70 degrees or less provided an R(2) value of 0.90. The output of the model was compared to data measured during the first 6 months of 2005 for an SZA of 70 degrees or less and provided an R(2) value of approximately 0.82.

A 24.5-Year Global Dataset of Direct Normal Irradiance: Result from the Application of a Global-to-Beam Model to the NASA GEWEX SRB Global Horizontal Irradiance

NASA Astrophysics Data System (ADS)

Zhang, T.; Stackhouse, P. W.; Chandler, W.; Hoell, J. M., Jr.; Westberg, D. J.

2015-12-01

The DIRINDEX model has previously been applied to the NASA GEWEX SRB Release 3.0 global horizontal irradiances (GHIs) to derive 3-hourly, daily and monthly mean direct normal irradiances (DNIs) for the period from 2000 to 2005 (http://dx.doi.org/10.1016/j.solener.2014.09.006), though the model was originally designed to estimate hourly DNIs from hourly GHIs. Input to the DIRINDEX model comprised 1.) the 3-hourly all-sky and clear-sky GHIs from the GEWEX SRB dataset; 2.) the surface pressure and the atmospheric column water vapor from the GEOS4 dataset; and 3.) daily mean aerosol optical depth at 700 nm derived from the daily mean aerosol data from the Model of Atmospheric Transport and CHemistry (MATCH). The GEWEX SRB data is spatially available on a quasi-equal-area global grid system consisting of 44016 boxes ranging from 1 degree latitude by 1 degree longitude around the Equator to 1 degree latitude by 120 degree longitude next to the poles. The derived DNIs were on the same grid system. Due to the limited availability of the MATCH aerosol data, the model was applied to the years from 2000 to 2005 only. The results were compared with ground-based measurements from 39 sites of the Baseline Surface Radiation Network (BSRN). The comparison statistics show that the results were in better agreement with their BSRN counterparts than the current Surface meteorology and Solar Energy (SSE) Release 6.0 data (https://eosweb.larc.nasa.gov/sse/). In this paper, we present results from the model over the entire time span of the GEWEX SRB Release 3.0 data (July 1983 to December2007) in which the MERRA atmospheric data were substituted for the GEOS4 data, and the Max-Planck Aerosol Climatology Version 1 (MAC-v1) data for the MATCH data. As a consequence, we derived a 24.5-year DNI dataset of global coverage continuous from July 1983 to December 2007. Comparisons with the BSRN data show that the results are comparable in quality with that from the earlier application.

Global horizontal irradiance clear sky models : implementation and analysis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stein, Joshua S.; Hansen, Clifford W.; Reno, Matthew J.

2012-03-01

Clear sky models estimate the terrestrial solar radiation under a cloudless sky as a function of the solar elevation angle, site altitude, aerosol concentration, water vapor, and various atmospheric conditions. This report provides an overview of a number of global horizontal irradiance (GHI) clear sky models from very simple to complex. Validation of clear-sky models requires comparison of model results to measured irradiance during clear-sky periods. To facilitate validation, we present a new algorithm for automatically identifying clear-sky periods in a time series of GHI measurements. We evaluate the performance of selected clear-sky models using measured data from 30 differentmore » sites, totaling about 300 site-years of data. We analyze the variation of these errors across time and location. In terms of error averaged over all locations and times, we found that complex models that correctly account for all the atmospheric parameters are slightly more accurate than other models, but, primarily at low elevations, comparable accuracy can be obtained from some simpler models. However, simpler models often exhibit errors that vary with time of day and season, whereas the errors for complex models vary less over time.« less

Retrieving vertical ozone profiles from measurements of global spectral irradiance

NASA Astrophysics Data System (ADS)

Bernhard, Germar; Petropavlovskikh, Irina; Mayer, Bernhard

2017-12-01

A new method is presented to determine vertical ozone profiles from measurements of spectral global (direct Sun plus upper hemisphere) irradiance in the ultraviolet. The method is similar to the widely used Umkehr technique, which inverts measurements of zenith sky radiance. The procedure was applied to measurements of a high-resolution spectroradiometer installed near the centre of the Greenland ice sheet. Retrieved profiles were validated with balloon-sonde observations and ozone profiles from the space-borne Microwave Limb Sounder (MLS). Depending on altitude, the bias between retrieval results presented in this paper and MLS observations ranges between -5 and +3 %. The magnitude of this bias is comparable, if not smaller, to values reported in the literature for the standard Dobson Umkehr method. Total ozone columns (TOCs) calculated from the retrieved profiles agree to within 0.7±2.0 % (±1σ) with TOCs measured by the Ozone Monitoring Instrument on board the Aura satellite. The new method is called the Global-Umkehr method.

Solutions Network Formulation Report. Aerosol Polarimetry Sensor Measurements of Diffuse-to-Global Irradiance Ratio for Improved Forecasting of Plant Productivity and Health

NASA Technical Reports Server (NTRS)

Knowlton, Kelly; Andrews, Jane C.; Ryan, Robert E.

2007-01-01

Studies have shown that vegetation is directly sensitive to changes in the diffuse-to-global irradiance ratio and that increased percentage of diffuse irradiation can accelerate photosynthesis. Therefore, measurements of diffuse versus global irradiance could be useful for monitoring crop productivity and overall vegetative health as they relate to the total amount of particulates in the air that result from natural disasters or anthropogenic (manmade) causes. While the components of solar irradiance are measured by satellite and surface sensors and calculated with atmospheric models, disagreement exists between the results, creating a need for more accurate and comprehensive retrievals of atmospheric aerosol parameters. Two satellite sensors--APS and VIIRS--show promise for retrieving aerosol properties at an unprecedented level of accuracy. APS is expected to be launched in December 2008. The planned launch date for VIIRS onboard NPP is September 2009. Identified partners include the USDA s ARS, North Carolina State University, Purdue Climate Change Research Center, and the Cooperative Institute for Research in the Atmosphere at Colorado State University. Although at present no formal DSSs (decision support systems) require accurate values of diffuse-to-global irradiance, this parameter is sufficiently important that models are being developed that will incorporate these measurements. This candidate solution is aligned with the Agricultural Efficiency and Air Quality National Applications.

Quantitative Assessment of the Integrated Response in Global Heat and Moisture Budgets to Changing Solar Irradiance

NASA Technical Reports Server (NTRS)

White, Warren B.; Cayan, Daniel R.; Dettinger, Michael; Sharber, James (Technical Monitor)

2001-01-01

Earlier, we found time sequences of basin- and global-average upper ocean temperature (that is, diabatic heat storage above the main pycnocline) for 40 years from 1955-1994 and of sea surface temperature for 95 years from 1900-1994 associated with changes in the Sun's radiative forcing on decadal and interdecadal timescales, lagging by 10 deg.- 30 deg. of phase and confined to the upper 60-120 m. Yet, the observed changes in upper ocean temperature (approx. 0.1 K) were approximately twice those expected from the Stefan-Boltzmann black-body radiation law for the Earth's surface, with phase lags (0 deg. to 30 deg. of phase) much shorter than the 90 deg. phase shift expected as well. Moreover, White et al. (1997, 1998) found the Earth's global decadal mode in covarying SST and SLP anomalies phase locked to the decadal signal in the Sun's irradiance. Yet, Allan (2000) found this decadal signal also characterized by patterns similar to those observed on biennial and interannual time scales; that is, the Troposphere Biennial Oscillation (TBO) and the El Nino and the Southern Oscillation (ENSO). This suggested that small changes in the Sun's total irradiance could excite this global decadal mode in the Earth's ocean-atmosphere-terrestrial system similar to those excited internally on biennial and interannual period scales. This is a significant finding, proving that energy budget models (that is, models based on globally-averaged radiation balances) yield unrealistic responses. Thus, the true response must include positive and negative feedbacks in the Earth's ocean-atmosphere-terrestrial system as its internal mode (that is, the natural mode of the system) respond in damped resonance to quasi-periodic decadal changes in the Sun's irradiance. Moreover, these responses are not much different from those occurring internally on biennial and interannual period scales.

Long-term global temperature variations under total solar irradiance, cosmic rays, and volcanic activity.

PubMed

Biktash, Lilia

2017-07-01

The effects of total solar irradiance (TSI) and volcanic activity on long-term global temperature variations during solar cycles 19-23 were studied. It was shown that a large proportion of climate variations can be explained by the mechanism of action of TSI and cosmic rays (CRs) on the state of the lower atmosphere and other meteorological parameters. The role of volcanic signals in the 11-year variations of the Earth's climate can be expressed as several years of global temperature drop. Conversely, it was shown that the effects of solar, geophysical, and human activity on climate change interact. It was concluded that more detailed investigations of these very complicated relationships are required, in order to be able to understand issues that affect ecosystems on a global scale.

Using Global Total Electron Content to Understand Interminimum Changes in Solar EUV Irradiance and Thermospheric Composition

NASA Astrophysics Data System (ADS)

McDonald, S. E.; Emmert, J. T.; Krall, J.; Mannucci, A. J.; Vergados, P.

2017-12-01

To understand how and why the distribution of geospace plasma in the ionosphere/plasmasphere is evolving over multi-decadal time scales in response to solar, heliospheric and atmospheric forcing, it is critically important to have long-term, stable datasets. In this study, we use a newly constructed dataset of GPS-based total electron content (TEC) developed by JPL. The JPL Global Ionosphere Mapping (GIM) algorithm was used to generate a 35-station dataset spanning two solar minimum periods (1993-2014). We also use altimeter-derived TEC measurements from TOPEX-Poseidon and Jason-1 to construct a continuous dataset for the 1995-2014 time period. Both longterm datasets are compared to each other to study interminimum changes in the global TEC (during 1995-1995 and 2008-2009). We use the SAMI3 physics-based model of the ionosphere to compare the simulations of 1995-2014 with the JPL TEC and TOPEX/Jason-1 datasets. To drive SAMI3, we use the Naval Research Laboratory Solar Spectral Irradiance (NRLSSI) model to specify the EUV irradiances, and NRLMSIS to specify the thermosphere. We adjust the EUV irradiances and thermospheric constituents to match the TEC datasets and draw conclusions regarding sources of the differences between the two solar minimum periods.

A technique for global monitoring of net solar irradiance at the ocean surface. II - Validation

NASA Technical Reports Server (NTRS)

Chertock, Beth; Frouin, Robert; Gautier, Catherine

1992-01-01

The generation and validation of the first satellite-based long-term record of surface solar irradiance over the global oceans are addressed. The record is generated using Nimbus-7 earth radiation budget (ERB) wide-field-of-view plentary-albedo data as input to a numerical algorithm designed and implemented based on radiative transfer theory. The mean monthly values of net surface solar irradiance are computed on a 9-deg latitude-longitude spatial grid for November 1978-October 1985. The new data set is validated in comparisons with short-term, regional, high-resolution, satellite-based records. The ERB-based values of net surface solar irradiance are compared with corresponding values based on radiance measurements taken by the Visible-Infrared Spin Scan Radiometer aboard GOES series satellites. Errors in the new data set are estimated to lie between 10 and 20 W/sq m on monthly time scales.

An unsupervised method for estimating the global horizontal irradiance from photovoltaic power measurements

NASA Astrophysics Data System (ADS)

Nespoli, Lorenzo; Medici, Vasco

2017-12-01

In this paper, we present a method to determine the global horizontal irradiance (GHI) from the power measurements of one or more PV systems, located in the same neighborhood. The method is completely unsupervised and is based on a physical model of a PV plant. The precise assessment of solar irradiance is pivotal for the forecast of the electric power generated by photovoltaic (PV) plants. However, on-ground measurements are expensive and are generally not performed for small and medium-sized PV plants. Satellite-based services represent a valid alternative to on site measurements, but their space-time resolution is limited. Results from two case studies located in Switzerland are presented. The performance of the proposed method at assessing GHI is compared with that of free and commercial satellite services. Our results show that the presented method is generally better than satellite-based services, especially at high temporal resolutions.

Statistical analysis of global horizontal solar irradiation GHI in Fez city, Morocco

NASA Astrophysics Data System (ADS)

Bounoua, Z.; Mechaqrane, A.

2018-05-01

An accurate knowledge of the solar energy reaching the ground is necessary for sizing and optimizing the performances of solar installations. This paper describes a statistical analysis of the global horizontal solar irradiation (GHI) at Fez city, Morocco. For better reliability, we have first applied a set of check procedures to test the quality of hourly GHI measurements. We then eliminate the erroneous values which are generally due to measurement or the cosine effect errors. Statistical analysis show that the annual mean daily values of GHI is of approximately 5 kWh/m²/day. Daily monthly mean values and other parameter are also calculated.

A Comparison Between Heliosat-2 and Artificial Neural Network Methods for Global Horizontal Irradiance Retrievals over Desert Environments

NASA Astrophysics Data System (ADS)

Ghedira, H.; Eissa, Y.

2012-12-01

Global horizontal irradiance (GHI) retrievals at the surface of any given location could be used for preliminary solar resource assessments. More accurately, the direct normal irradiance (DNI) and diffuse horizontal irradiance (DHI) are also required to estimate the global tilt irradiance, mainly used for fixed flat plate collectors. Two different satellite-based models for solar irradiance retrievals have been applied over the desert environment of the United Arab Emirates (UAE). Both models employ channels of the SEVIRI instrument, onboard the geostationary satellite Meteosat Second Generation, as their main inputs. The satellite images used in this study have a temporal resolution of 15-min and a spatial resolution of 3-km. The objective of this study is to compare between the GHI retrieved using the Heliosat-2 method and an artificial neural network (ANN) ensemble method over the UAE. The high-resolution visible channel of SEVIRI is used in the Heliosat-2 method to derive the cloud index. The cloud index is then used to compute the cloud transmission, while the cloud-free GHI is computed from the Linke turbidity factor. The product of the cloud transmission and the cloud-free GHI denotes the estimated GHI. A constant underestimation is observed in the estimated GHI over the dataset available in the UAE. Therefore, the cloud-free DHI equation in the model was recalibrated to fix the bias. After recalibration, results over the UAE show a root mean square error (RMSE) value of 10.1% and a mean bias error (MBE) of -0.5%. As for the ANN approach, six thermal channels of SEVIRI were used to estimate the DHI and the total optical depth of the atmosphere (δ). An ensemble approach is employed to obtain a better generalizability of the results, as opposed to using one single weak network. The DNI is then computed from the estimated δ using the Beer-Bouguer-Lambert law. The GHI is computed from the DNI and DHI estimates. The RMSE for the estimated GHI obtained over an

Prediction of global solar irradiance based on time series analysis: Application to solar thermal power plants energy production planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, Luis; Marchante, Ruth; Cony, Marco

2010-10-15

Due to strong increase of solar power generation, the predictions of incoming solar energy are acquiring more importance. Photovoltaic and solar thermal are the main sources of electricity generation from solar energy. In the case of solar thermal energy plants with storage energy system, its management and operation need reliable predictions of solar irradiance with the same temporal resolution as the temporal capacity of the back-up system. These plants can work like a conventional power plant and compete in the energy stock market avoiding intermittence in electricity production. This work presents a comparisons of statistical models based on time seriesmore » applied to predict half daily values of global solar irradiance with a temporal horizon of 3 days. Half daily values consist of accumulated hourly global solar irradiance from solar raise to solar noon and from noon until dawn for each day. The dataset of ground solar radiation used belongs to stations of Spanish National Weather Service (AEMet). The models tested are autoregressive, neural networks and fuzzy logic models. Due to the fact that half daily solar irradiance time series is non-stationary, it has been necessary to transform it to two new stationary variables (clearness index and lost component) which are used as input of the predictive models. Improvement in terms of RMSD of the models essayed is compared against the model based on persistence. The validation process shows that all models essayed improve persistence. The best approach to forecast half daily values of solar irradiance is neural network models with lost component as input, except Lerida station where models based on clearness index have less uncertainty because this magnitude has a linear behaviour and it is easier to simulate by models. (author)« less

The impact of laser irradiation on global stability in patients with vertebrobasilar insufficiency: A clinical report

PubMed Central

Lukowicz, Malgorzata; Zalewski, Pawel; Bulatowicz, Irena; Buszko, Katarzyna; Klawe, Jacek J.

2011-01-01

Summary Background The purpose of our experiment was to determine whether laser stimulation can improve microcirculation in the posterior regions of the brain in patients with vertebrobasilar insufficiency (VBI). Material/Methods We studied 25 patients (20 female, 5 male, mean age 64) diagnosed with chronic VBI. All were evaluated using the De Klyn test, followed by qualitative assessment of stability using a Berg Balance Scale and evaluation of global stability using an electronic balance platform. A CTL-1100 low power laser was used with standard parameters. We established a protocol for laser irradiation at 5 points along the vertebral artery in the cervical region bilaterally. Irradiation was performed 10 times over two weeks. Results Significant improvement occurred after therapy in headache (p=0.0005), vertigo (p<0.0000), and tinnitus (p=0.0387). No significant differences were observed in nausea or nystagmus caused by head rotation. The Berg Balance Scale results showed significant differences in almost all features. There was a tendency towards improved stability in all parameters, and statistically significant differences in the total surface of support and the spread surface of support for the left foot. Conclusions Laser stimulation as applied in this study can be useful in the treatment of patients with VBI. The main reason for improvement in global stability, balance, and other VBI symptoms is better blood perfusion. PMID:21873949

Active Cavity Irradiance Monitor Satellite ACRIMSAT Artist Concept

NASA Image and Video Library

1999-12-21

The Active Cavity Irradiance Monitor Satellite, or ACRIMSAT, mission is a climate change investigation that measures changes in how much of the sun's energy reaches Earth's atmosphere. This energy, called solar irradience, creates winds, heats the land and drives ocean currents, and therefore contains significant data that climatologists can use to improve predictions of climate change and global warming. The satellite's Active Cavity Irradiance Monitor III instrument, now in its third generation, has been used since the 1980s to study solar irradiance and its impacts on global warming. Scientists, using data from the instrument, now theorize that there is a significant correlation between solar radiation and global warming. ACRIMSAT completed its five-year primary mission in 2005 when it began operating under its extended mission. http://photojournal.jpl.nasa.gov/catalog/PIA18157

Hyperspectral radiometer for automated measurement of global and diffuse sky irradiance

NASA Astrophysics Data System (ADS)

Kuusk, Joel; Kuusk, Andres

2018-01-01

An automated hyperspectral radiometer for the measurement of global and diffuse sky irradiance, SkySpec, has been designed for providing the SMEAR-Estonia research station with spectrally-resolved solar radiation data. The spectroradiometer has been carefully studied in the optical radiometry laboratory of Tartu Observatory, Estonia. Recorded signals are corrected for spectral stray light as well as for changes in dark signal and spectroradiometer spectral responsivity due to temperature effects. Comparisons with measurements of shortwave radiation fluxes made at the Baseline Surface Radiation Network (BSRN) station at Tõravere, Estonia, and with fluxes simulated using the atmospheric radiative transfer model 6S and Aerosol Robotic Network (AERONET) data showed that the spectroradiometer is a reliable instrument that provides accurate estimates of integrated fluxes and of their spectral distribution. The recorded spectra can be used to estimate the amount of atmospheric constituents such as aerosol and column water vapor, which are needed for the atmospheric correction of spectral satellite images.

Global Horizontal Irradiance Anomalies in Long Term Series Over India

NASA Astrophysics Data System (ADS)

Cony, Marco; Liria, Juan; Weisenberg, Ralf; Serrano, Enrique

2014-05-01

India has a high potential for solar energy applications due to its geographic position within the Sun Belt and the large number of cloudless days in many regions of the country. However, certain regions of India, particularly those largely populated, can exhibit large aerosol loading in the atmosphere as a consequence of anthropogenic emissions that could have a negative feedback in the solar resource potential. This effect, named as solar dimming, has already been observed in India, and in some other regions in the world, by some authors using ground data from the last two decades. The recent interest in the promotion of solar energy applications in India highlights the need of extending and improving the knowledge of the solar radiation resources in this country, since most of the long term measurements available correspond to global horizontal radiation (GHI) and most of them are also located big cities or highly populated areas. In addition, accurate knowledge on the aerosol column quantification and on its dynamical behavior with high spatial resolution is particularly important in the case of India, due to their impact on direct normal irradiation. Long term studies of solar irradiation over India can be performed using monthly means of GHI measurements from the Indian Meteorological Department. Ground data are available from 1964 till today through the World Radiation Data Centre that publish these values in the web. This work shows a long term analysis of GHI using anomalies techniques over ten different sites over India. Besides, techniques of linear trends have been applied for to show the evolution over this period. The analysis of anomalies has also found two periods of different behavior. From 1964 till 1988 the anomalies observed were positive and the last 20 years seems to be a period of negative anomalies. The results exhibit a decreasing trend and negative anomalies confirming thus the darkening effect already reported by solar dimming studies

Phytosanitary irradiation and fresh fruit quality: Cultivar and maturity effects

USDA-ARS?s Scientific Manuscript database

Irradiation is an effective quarantine treatment for global trade of fresh produce. Variation in cultivars and maturity stages can impact the tolerance of fresh fruits to irradiation for the purposes of quarantine security. Tolerance thresholds for irradiated fruit are lacking for a large number of ...

Advanced solar irradiances applied to satellite and ionospheric operational systems

NASA Astrophysics Data System (ADS)

Tobiska, W. Kent; Schunk, Robert; Eccles, Vince; Bouwer, Dave

Satellite and ionospheric operational systems require solar irradiances in a variety of time scales and spectral formats. We describe the development of a system using operational grade solar irradiances that are applied to empirical thermospheric density models and physics-based ionospheric models used by operational systems that require a space weather characterization. The SOLAR2000 (S2K) and SOLARFLARE (SFLR) models developed by Space Environment Technologies (SET) provide solar irradiances from the soft X-rays (XUV) through the Far Ultraviolet (FUV) spectrum. The irradiances are provided as integrated indices for the JB2006 empirical atmosphere density models and as line/band spectral irradiances for the physics-based Ionosphere Forecast Model (IFM) developed by the Space Environment Corporation (SEC). We describe the integration of these irradiances in historical, current epoch, and forecast modes through the Communication Alert and Prediction System (CAPS). CAPS provides real-time and forecast HF radio availability for global and regional users and global total electron content (TEC) conditions.

Phytosanitary irradiation - Development and application

NASA Astrophysics Data System (ADS)

Hallman, Guy J.; Loaharanu, Paisan

2016-12-01

Phytosanitary irradiation, the use of ionizing radiation to disinfest traded agricultural commodities of regulated pests, is a growing use of food irradiation that has great continued potential for increase in commercial application. In 2015 approximately 25,000 t of fresh fruits and vegetables were irradiated globally for phytosanitary purposes. Phytosanitary irradiation has resulted in a paradigm shift in phytosanitation in that the final burden of proof of efficacy of the treatment has shifted from no live pests upon inspection at a port of entry (as for all previous phytosanitary treatments) to total dependence on certification that the treatment for target pests is based on adequate science and is commercially conducted and protected from post-treatment infestation. In this regard phytosanitary irradiation is managed more like a hazard analysis and critical control point (HACCP) approach more consistent with food safety than phytosanitation. Thus, phytosanitary irradiation offers a more complete and rigorous methodology for safeguarding than other phytosanitary measures. The role of different organizations in achieving commercial application of phytosanitary irradiation is discussed as well as future issues and applications, including new generic doses.

Spatial And Temporal Patterns As Well As Major Influencing Factors Of Global And Diffuse Horizontal Irradiance Over China: 1960-2014

NASA Astrophysics Data System (ADS)

Wang, H.; Sun, F.

2017-12-01

Global Horizontal Irradiance (GHI) on Earth is a central element of climate systems. With changes in the climate and regional development, the patterns and influencing factors of GHI, in addition to presenting global consistency, are increasingly showing regional particularities. Based on data for GHI, Diffuse Horizontal Irradiance (DHI) and potential impact factors (geographical position, elevation, cloud cover, water vapor, and ground atmospheric transparency related variables) from 1960 to 2014 in China, we analyzed the pattern and major influencing factors of GHI and DHI. The results showed that the major influencing factors of the GHI spatial pattern were the total cloud cover (TCC) and relative humidity (RH) in China. Dividing all of China into two regions, the major factors were the water vapor pressure (WVP) in the northern region and TCC in the southern region. And we divided the GHI and DHI data into two periods (1960-1987 and 1988-2014) due to global dimming and brightening observed in China in the late 1980's. The temporal GHI showed that 31 of 58 decreased significantly with an average decreasing rate of 95 MJ.10yr-1 during the periods of 1960-2014 and 49 of 76 stations decreased significantly with an rate of 342 MJ.10yr-1 during 1960-1987, whereas 57 of 88 stations did not change and 24 stations increased significantly with an rate of 201 MJ.10yr-1 during the period of 1988-2014. The temporal DHI showed that 40 of 61sites did not change significantly from 1960 to 1987. The major influencing factors for temporal changes of GHI in nine typical cities from 1960 to 2013 were as follows: air quality-related variables in super cities, sandstorms and wind in desert oasis cities, clouds in cities with good air quality and a low cloud amount (LCA) and annual fog days (FD) in Chengdu. Overall, we identified characteristics of GHI and DHI based on global climate change and regional urban development and found that the spatial characteristics of GHI results for

Photosynthesis-irradiance parameters of marine phytoplankton: synthesis of a global data set

NASA Astrophysics Data System (ADS)

Bouman, Heather A.; Platt, Trevor; Doblin, Martina; Figueiras, Francisco G.; Gudmundsson, Kristinn; Gudfinnsson, Hafsteinn G.; Huang, Bangqin; Hickman, Anna; Hiscock, Michael; Jackson, Thomas; Lutz, Vivian A.; Mélin, Frédéric; Rey, Francisco; Pepin, Pierre; Segura, Valeria; Tilstone, Gavin H.; van Dongen-Vogels, Virginie; Sathyendranath, Shubha

2018-02-01

The photosynthetic performance of marine phytoplankton varies in response to a variety of factors, environmental and taxonomic. One of the aims of the MArine primary Production: model Parameters from Space (MAPPS) project of the European Space Agency is to assemble a global database of photosynthesis-irradiance (P-E) parameters from a range of oceanographic regimes as an aid to examining the basin-scale variability in the photophysiological response of marine phytoplankton and to use this information to improve the assignment of P-E parameters in the estimation of global marine primary production using satellite data. The MAPPS P-E database, which consists of over 5000 P-E experiments, provides information on the spatio-temporal variability in the two P-E parameters (the assimilation number, PmB, and the initial slope, αB, where the superscripts B indicate normalisation to concentration of chlorophyll) that are fundamental inputs for models (satellite-based and otherwise) of marine primary production that use chlorophyll as the state variable. Quality-control measures consisted of removing samples with abnormally high parameter values and flags were added to denote whether the spectral quality of the incubator lamp was used to calculate a broad-band value of αB. The MAPPS database provides a photophysiological data set that is unprecedented in number of observations and in spatial coverage. The database will be useful to a variety of research communities, including marine ecologists, biogeochemical modellers, remote-sensing scientists and algal physiologists. The compiled data are available at https://doi.org/10.1594/PANGAEA.874087 (Bouman et al., 2017).

Forecasting Global Horizontal Irradiance Using the LETKF and a Combination of Advected Satellite Images and Sparse Ground Sensors

NASA Astrophysics Data System (ADS)

Harty, T. M.; Lorenzo, A.; Holmgren, W.; Morzfeld, M.

2017-12-01

The irradiance incident on a solar panel is the main factor in determining the power output of that panel. For this reason, accurate global horizontal irradiance (GHI) estimates and forecasts are critical when determining the optimal location for a solar power plant, forecasting utility scale solar power production, or forecasting distributed, behind the meter rooftop solar power production. Satellite images provide a basis for producing the GHI estimates needed to undertake these objectives. The focus of this work is to combine satellite derived GHI estimates with ground sensor measurements and an advection model. The idea is to use accurate but sparsely distributed ground sensors to improve satellite derived GHI estimates which can cover large areas (the size of a city or a region of the United States). We use a Bayesian framework to perform the data assimilation, which enables us to produce irradiance forecasts and associated uncertainties which incorporate both satellite and ground sensor data. Within this framework, we utilize satellite images taken from the GOES-15 geostationary satellite (available every 15-30 minutes) as well as ground data taken from irradiance sensors and rooftop solar arrays (available every 5 minutes). The advection model, driven by wind forecasts from a numerical weather model, simulates cloud motion between measurements. We use the Local Ensemble Transform Kalman Filter (LETKF) to perform the data assimilation. We present preliminary results towards making such a system useful in an operational context. We explain how localization and inflation in the LETKF, perturbations of wind-fields, and random perturbations of the advection model, affect the accuracy of our estimates and forecasts. We present experiments showing the accuracy of our forecasted GHI over forecast-horizons of 15 mins to 1 hr. The limitations of our approach and future improvements are also discussed.

The effects of sunspots on solar irradiance

NASA Technical Reports Server (NTRS)

Hudson, H. S.; Silva, S.; Woodard, M.; Willson, R. C.

1982-01-01

It is pointed out that the darkness of a sunspot on the visible hemisphere of the sun will reduce the solar irradiance on the earth. Approaches are discussed for obtaining a crude estimate of the irradiance deficit produced by sunspots and of the total luminosity reduction for the whole global population of sunspots. Attention is given to a photometric sunspot index, a global measure of spot flux deficit, and models for the compensating flux excess. A model is shown for extrapolating visible-hemisphere spot areas to the invisible hemisphere. As an illustration, this extrapolation is used to calculate a very simple model for the reradiation necessary to balance the flux deficit.

Short-Term Global Horizontal Irradiance Forecasting Based on Sky Imaging and Pattern Recognition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodge, Brian S; Feng, Cong; Cui, Mingjian

Accurate short-term forecasting is crucial for solar integration in the power grid. In this paper, a classification forecasting framework based on pattern recognition is developed for 1-hour-ahead global horizontal irradiance (GHI) forecasting. Three sets of models in the forecasting framework are trained by the data partitioned from the preprocessing analysis. The first two sets of models forecast GHI for the first four daylight hours of each day. Then the GHI values in the remaining hours are forecasted by an optimal machine learning model determined based on a weather pattern classification model in the third model set. The weather pattern ismore » determined by a support vector machine (SVM) classifier. The developed framework is validated by the GHI and sky imaging data from the National Renewable Energy Laboratory (NREL). Results show that the developed short-term forecasting framework outperforms the persistence benchmark by 16% in terms of the normalized mean absolute error and 25% in terms of the normalized root mean square error.« less

Uncertainty Estimate of Surface Irradiances Computed with MODIS-, CALIPSO-, and CloudSat-Derived Cloud and Aerosol Properties

NASA Astrophysics Data System (ADS)

Kato, Seiji; Loeb, Norman G.; Rutan, David A.; Rose, Fred G.; Sun-Mack, Sunny; Miller, Walter F.; Chen, Yan

2012-07-01

Differences of modeled surface upward and downward longwave and shortwave irradiances are calculated using modeled irradiance computed with active sensor-derived and passive sensor-derived cloud and aerosol properties. The irradiance differences are calculated for various temporal and spatial scales, monthly gridded, monthly zonal, monthly global, and annual global. Using the irradiance differences, the uncertainty of surface irradiances is estimated. The uncertainty (1σ) of the annual global surface downward longwave and shortwave is, respectively, 7 W m-2 (out of 345 W m-2) and 4 W m-2 (out of 192 W m-2), after known bias errors are removed. Similarly, the uncertainty of the annual global surface upward longwave and shortwave is, respectively, 3 W m-2 (out of 398 W m-2) and 3 W m-2 (out of 23 W m-2). The uncertainty is for modeled irradiances computed using cloud properties derived from imagers on a sun-synchronous orbit that covers the globe every day (e.g., moderate-resolution imaging spectrometer) or modeled irradiances computed for nadir view only active sensors on a sun-synchronous orbit such as Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation and CloudSat. If we assume that longwave and shortwave uncertainties are independent of each other, but up- and downward components are correlated with each other, the uncertainty in global annual mean net surface irradiance is 12 W m-2. One-sigma uncertainty bounds of the satellite-based net surface irradiance are 106 W m-2 and 130 W m-2.

Modeling the relationship between photosynthetically active radiation and global horizontal irradiance using singular spectrum analysis

NASA Astrophysics Data System (ADS)

Zempila, Melina-Maria; Taylor, Michael; Bais, Alkiviadis; Kazadzis, Stelios

2016-10-01

We report on the construction of generic models to calculate photosynthetically active radiation (PAR) from global horizontal irradiance (GHI), and vice versa. Our study took place at stations of the Greek UV network (UVNET) and the Hellenic solar energy network (HNSE) with measurements from NILU-UV multi-filter radiometers and CM pyranometers, chosen due to their long (≈1 M record/site) high temporal resolution (≈1 min) record that captures a broad range of atmospheric environments and cloudiness conditions. The uncertainty of the PAR measurements is quantified to be ±6.5% while the uncertainty involved in GHI measurements is up to ≈±7% according to the manufacturer. We show how multi-linear regression and nonlinear neural network (NN) models, trained at a calibration site (Thessaloniki) can be made generic provided that the input-output time series are processed with multi-channel singular spectrum analysis (M-SSA). Without M-SSA, both linear and nonlinear models perform well only locally. M-SSA with 50 time-lags is found to be sufficient for identification of trend, periodic and noise components in aerosol, cloud parameters and irradiance, and to construct regularized noise models of PAR from GHI irradiances. Reconstructed PAR and GHI time series capture ≈95% of the variance of the cross-validated target measurements and have median absolute percentage errors <2%. The intra-site median absolute error of M-SSA processed models were ≈8.2±1.7 W/m2 for PAR and ≈9.2±4.2 W/m2 for GHI. When applying the models trained at Thessaloniki to other stations, the average absolute mean bias between the model estimates and measured values was found to be ≈1.2 W/m2 for PAR and ≈0.8 W/m2 for GHI. For the models, percentage errors are well within the uncertainty of the measurements at all sites. Generic NN models were found to perform marginally better than their linear counterparts.

Improvements of top-of-atmosphere and surface irradiance computations with CALIPSO-, CloudSat-, and MODIS-derived cloud and aerosol properties

NASA Astrophysics Data System (ADS)

Kato, Seiji; Rose, Fred G.; Sun-Mack, Sunny; Miller, Walter F.; Chen, Yan; Rutan, David A.; Stephens, Graeme L.; Loeb, Norman G.; Minnis, Patrick; Wielicki, Bruce A.; Winker, David M.; Charlock, Thomas P.; Stackhouse, Paul W., Jr.; Xu, Kuan-Man; Collins, William D.

2011-10-01

One year of instantaneous top-of-atmosphere (TOA) and surface shortwave and longwave irradiances are computed using cloud and aerosol properties derived from instruments on the A-Train Constellation: the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite, the CloudSat Cloud Profiling Radar (CPR), and the Aqua Moderate Resolution Imaging Spectrometer (MODIS). When modeled irradiances are compared with those computed with cloud properties derived from MODIS radiances by a Clouds and the Earth's Radiant Energy System (CERES) cloud algorithm, the global and annual mean of modeled instantaneous TOA irradiances decreases by 12.5 W m-2 (5.0%) for reflected shortwave and 2.5 W m-2 (1.1%) for longwave irradiances. As a result, the global annual mean of instantaneous TOA irradiances agrees better with CERES-derived irradiances to within 0.5W m-2 (out of 237.8 W m-2) for reflected shortwave and 2.6W m-2 (out of 240.1 W m-2) for longwave irradiances. In addition, the global annual mean of instantaneous surface downward longwave irradiances increases by 3.6 W m-2 (1.0%) when CALIOP- and CPR-derived cloud properties are used. The global annual mean of instantaneous surface downward shortwave irradiances also increases by 8.6 W m-2 (1.6%), indicating that the net surface irradiance increases when CALIOP- and CPR-derived cloud properties are used. Increasing the surface downward longwave irradiance is caused by larger cloud fractions (the global annual mean by 0.11, 0.04 excluding clouds with optical thickness less than 0.3) and lower cloud base heights (the global annual mean by 1.6 km). The increase of the surface downward longwave irradiance in the Arctic exceeds 10 W m-2 (˜4%) in winter because CALIOP and CPR detect more clouds in comparison with the cloud detection by the CERES cloud algorithm during polar night. The global annual mean surface downward longwave irradiance of

Retrieval of the aerosol optical thickness from UV global irradiance measurements

NASA Astrophysics Data System (ADS)

Costa, M. J.; Salgueiro, V.; Bortoli, D.; Obregón, M. A.; Antón, M.; Silva, A. M.

2015-12-01

The UV irradiance is measured at Évora since several years, where a CIMEL sunphotometer integrated in AERONET is also installed. In the present work, measurements of UVA (315 - 400 nm) irradiances taken with Kipp&Zonen radiometers, as well as satellite data of ozone total column values, are used in combination with radiative transfer calculations, to estimate the aerosol optical thickness (AOT) in the UV. The retrieved UV AOT in Évora is compared with AERONET AOT (at 340 and 380 nm) and a fairly good agreement is found with a root mean square error of 0.05 (normalized root mean square error of 8.3%) and a mean absolute error of 0.04 (mean percentage error of 2.9%). The methodology is then used to estimate the UV AOT in Sines, an industrialized site on the Atlantic western coast, where the UV irradiance is monitored since 2013 but no aerosol information is available.

Estimation of height-dependent solar irradiation and application to the solar climate of Iran

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samimi, J.

1994-05-01

An explicitly height-dependent model has been used to estimate the solar irradiation over Iran which has a vast range of altitudes. The parameters of the model have been chosen on general grounds and not by parameters best fitting to any of the available measured irradiation data in Iran. The estimated global solar irradiation on the horizontal surface shows a very good agreement (4.1% deviation) with the 17-year long pyranometric measurements in Tehran, and also, is in good agreement with other, shorter available measured data. The entire data base of the Iranian meteorological stations have been used to establish a simplemore » relation between the sunshine duration records and the cloud cover reports which can be utilized in solar energy estimations for sites with no sunshine duration recorders. Clear sky maps of Iran for direct solar irradiation on tracking, horizontal, and south-facing vertical planes are presented. The global solar irradiation map for horizontal surface with cloudiness is zoned into four irradiation zones. In about four-fifths of the land in Iran, the annual-mean daily global solar irradiation on horizontal surface ranges from 4.5 to 5.4 kWh/m[sup 2].« less

Implications of solar irradiance variability upon long-term changes in the Earth's atmospheric temperatures

NASA Technical Reports Server (NTRS)

Lee, Robert B., III

1992-01-01

From 1979 through 1987, it is believed that variability in the incoming solar energy played a significant role in changing the Earth's climate. Using high-precision spacecraft radiometric measurements, the incoming total solar irradiance (total amount of solar power per unit area) and the Earth's mean, global atmospheric temperatures were found to vary in phase with each other. The observed irradiance and temperature changes appeared to be correlated with the 11-year cycle of solar magnetic activity. During the period from 1979 through 1985, both the irradiance and temperature decreased. From 1985 to 1987, they increased. The irradiance changed approximately 0.1 percent, while the temperature varied as much as 0.6 C. During the 1979-1987 period, the temperatures were forecasted to rise linearly because of the anthropogenic build-up of carbon dioxide and the hypothesized 'global warming', 'greenhouse effect', scenarios. Contrary to these scenarios, the temperatures were found to vary in a periodic manner in phase with the solar irradiance changes. The observed correlations between irradiance and temperature variabilily suggest that the mean, global temperature of the Earth may decline between 1990 and 1997 as solar magnetic activity decreases.

Recent changes in solar irradiance and infrared irradiance related with air temperature and cloudiness at the King Sejong Station, Antarctica

NASA Astrophysics Data System (ADS)

Jung, Y.; Kim, J.; Cho, H.; Lee, B.

2006-12-01

The polar region play a critical role in the surface energy balance and the climate system of the Earth. The important question in the region is that what is the role of the Antarctic atmospheric heat sink of global climate. Thus, this study shows the trends of global solar irradiance, infrared irradiance, air temperature and cloudiness measured at the King Sejong station, Antarctica, during the period of 1996-2004 and determines their relationship and variability of the surface energy balance. Annual average of solar radiation and cloudiness is 81.8 Wm-2 and 6.8 oktas and their trends show the decrease of -0.24 Wm-2yr-1(-0.30 %yr-1) and 0.02 oktas yr-1(0.30 %yr-1). The change of solar irradiance is directly related to change of cloudiness and decrease of solar irradiance presents radiative cooling at the surface. Monthly mean infrared irradiance, air temperature and specific humidity shows the decrease of -2.11 Wm^{- 2}yr-1(-0.75 %yr-1), -0.07 'Cyr-1(-5.15 %yr-1) and -0.044 gkg-1yr-1(-1.42 %yr-1), respectively. Annual average of the infrared irradiance is 279.9 Wm-2 and correlated with the air temperature, specific humidity and cloudiness. A multiple regression model for estimation of the infrared irradiance using the components has been developed. Effects of the components on the infrared irradiance changes show 52 %, 19 % and 10 % for air temperature, specific humidity and cloudiness, respectively. Among the components, air temperature has a great influence on infrared irradiance. Despite the increase of cloudiness, the decrease in the infrared irradiance is due to the decrease of air temperature and specific humidity which have a cooling effect. Therefore, the net radiation of the surface energy balance shows radiative cooling of negative 11-24 Wm^{- 2} during winter and radiative warming of positive 32-83 Wm-2 during the summer. Thus, the amount of shortage and surplus at the surface is mostly balanced by turbulent flux of sensible and latent heat.

On nonstationarity and antipersistency in global temperature series

NASA Astrophysics Data System (ADS)

KäRner, O.

2002-10-01

Statistical analysis is carried out for satellite-based global daily tropospheric and stratospheric temperature anomaly and solar irradiance data sets. Behavior of the series appears to be nonstationary with stationary daily increments. Estimating long-range dependence between the increments reveals a remarkable difference between the two temperature series. Global average tropospheric temperature anomaly behaves similarly to the solar irradiance anomaly. Their daily increments show antipersistency for scales longer than 2 months. The property points at a cumulative negative feedback in the Earth climate system governing the tropospheric variability during the last 22 years. The result emphasizes a dominating role of the solar irradiance variability in variations of the tropospheric temperature and gives no support to the theory of anthropogenic climate change. The global average stratospheric temperature anomaly proceeds like a 1-dim random walk at least up to 11 years, allowing good presentation by means of the autoregressive integrated moving average (ARIMA) models for monthly series.

Global upper ocean heat storage response to radiative forcing from changing solar irradiance and increasing greenhouse gas/aerosol concentrations

NASA Astrophysics Data System (ADS)

White, Warren B.; Cayan, Daniel R.; Lean, Judith

1998-09-01

We constructed gridded fields of diabatic heat storage changes in the upper ocean from 20°S to 60°N from historical temperature profiles collected from 1955 to 1996. We filtered these 42 year records for periods of 8 to 15 years and 15 to 30 years, producing depth-weighted vertical average temperature (DVT) changes from the sea surface to the top of the main pycnocline. Basin and global averages of these DVT changes reveal decadal and interdecadal variability in phase across the Indian, Pacific, Atlantic, and Global Oceans, each significantly correlated with changing surface solar radiative forcing at a lag of 0+/-2 years. Decadal and interdecadal changes in global average DVT are 0.06°+/-0.01°K and 0.04°K+/-0.01°K, respectively, the same as those expected from consideration of the Stefan-Boltzmann radiation balance (i.e., 0.3°K per Wm-2) in response to 0.1% changes in surface solar radiative forcing of 0.2 Wm-2 and 0.15 Wm-2, respectively. Global spatial patterns of DVT changes are similar to temperature changes simulated in coupled ocean-atmosphere models, suggesting that natural modes of Earth's variability are phase-locked to the solar irradiance cycle. A trend in global average DVT of 0.15°K over this 42 year record cannot be explained by changing surface solar radiative forcing. But when we consider the 0.5 Wm-2 increase in surface radiative forcing estimated from the increase in atmospheric greenhouse gas and aerosol (GGA) concentrations over this period [Intergovernmental Panel on Climate Change, 1995], the Stefan-Boltzmann radiation balance yields this observed change. Moreover, the sum of solar and GGA surface radiative forcing can explain the relatively sharp increase in global and basin average DVT in the late 1970's.

A method for estimating direct normal solar irradiation from satellite data for a tropical environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janjai, Serm

In order to investigate a potential use of concentrating solar power technologies and select an optimum site for these technologies, it is necessary to obtain information on the geographical distribution of direct normal solar irradiation over an area of interest. In this work, we have developed a method for estimating direct normal irradiation from satellite data for a tropical environment. The method starts with the estimation of global irradiation on a horizontal surface from MTSAT-1R satellite data and other ground-based ancillary data. Then a satellite-based diffuse fraction model was developed and used to estimate the diffuse component of the satellite-derivedmore » global irradiation. Based on this estimated global and diffuse irradiation and the solar radiation incident angle, the direct normal irradiation was finally calculated. To evaluate its performance, the method was used to estimate the monthly average hourly direct normal irradiation at seven pyrheliometer stations in Thailand. It was found that values of monthly average hourly direct normal irradiation from the measurements and those estimated from the proposed method are in reasonable agreement, with a root mean square difference of 16% and a mean bias of -1.6%, with respect to mean measured values. After the validation, this method was used to estimate the monthly average hourly direct normal irradiation over Thailand by using MTSAT-1R satellite data for the period from June 2005 to December 2008. Results from the calculation were displayed as hourly and yearly irradiation maps. These maps reveal that the direct normal irradiation in Thailand was strongly affected by the tropical monsoons and local topography of the country. (author)« less

Evaluation of the Delta-T SPN1 radiometer for the measurement of solar irradiance components

NASA Astrophysics Data System (ADS)

Estelles, Victor; Serrano, David; Segura, Sara; Wood, John; Webb, Nick; Utrillas, Maria Pilar

2016-04-01

In this study we analyse the performance of an SPN1 radiometer built by Delta-T Devices Ltd. to retrieve global solar irradiance at ground and its components (diffuse, direct) in comparison with measurements from two Kipp&Zonen CMP21 radiometers and a Kipp&Zonen CHP1 pirheliometer, mounted on an active Solys-2 suntracker at the Burjassot site (Valencia, Spain) using data acquired every minute during years 2013 - 2015. The measurement site is close to sea level (60 m a.s.l.), near the Mediterranean coast (10 km) and within the metropolitan area of Valencia City (over 1.500.000 inhabitants). The SPN1 is an inexpensive and versatile instrument for the measurement of the three components of the solar radiation without any mobile part and without any need to azimuthally align the instrument to track the sun (http://www.delta-t.co.uk). The three components of the solar radiation are estimated from a combination of measurements performed by 7 different miniature thermopiles. The SPN1 pyranometer measures the irradiance between 400 and 2700 nm, and the nominal uncertainty for the individual readings is about 8% ± 10 W/m2 (5% for the daily averages). The pyranometer Kipp&Zonen CMP21 model is a secondary standard for the measurement of broadband solar global irradiance in horizontal planes. Two ventilated CMP21 are used for the measurement of the global and diffuse irradiances. The expected total daily uncertainty of the radiometer is estimated to be 2%. The pirheliometer Kipp&Zonen CHP1 is designed for the measurement of the direct irradiance. The principles are similar to the CMP21 pyranometer. The results of the comparison show that the global irradiance from the SPN1 compares very well with the CMP21, with absolute RMSD and MBD differences below the combined uncertainties (15 W/m2 and -5.4 W/m2, respectively; relative RMSD of 3.1%). Both datasets are very well correlated, with a correlation coefficient higher than 0.997 and a slope and intercept very close to 1 and 0

Use of LiDAR for calculating solar irradiance on roofs and façades of buildings at city scale: Methodology, validation, and analysis

NASA Astrophysics Data System (ADS)

Cheng, Liang; Xu, Hao; Li, Shuyi; Chen, Yanming; Zhang, Fangli; Li, Manchun

2018-04-01

As the rate of urbanization continues to accelerate, the utilization of solar energy in buildings plays an increasingly important role in sustainable urban development. For this purpose, we propose a LiDAR-based joint approach for calculating the solar irradiance incident on roofs and façades of buildings at city scale, which includes a methodology for calculating solar irradiance, the validation of the proposed method, and analysis of its application. The calculation of surface irradiance on buildings may then inform photovoltaic power generation simulations, architectural design, and urban energy planning. Application analyses of the proposed method in the experiment area found that: (1) Global and direct irradiations vary significantly by hour, day, month and season, both following the same trends; however, diffuse irradiance essentially remains unchanged over time. (2) Roof irradiation, but not façade irradiation, displays distinct time-dependent patterns. (3) Global and direct irradiations on roofs are highly correlated with roof aspect and slope, with high global and direct irradiations observed on roofs of aspect 100-250° and slopes of 0-60°, whereas diffuse irradiation on roofs is only affected by roof slope. (4) The façade of a building receives higher levels of global and direct irradiations if facing southeast, south, and southwest; however, diffuse irradiation remains constant regardless of façade orientation.

The effect of surface irradiance on the absorption spectrum of chromophoric dissolved organic matter in the global ocean

NASA Astrophysics Data System (ADS)

Swan, Chantal M.; Nelson, Norman B.; Siegel, David A.; Kostadinov, Tihomir S.

2012-05-01

The cycling pathways of chromophoric dissolved organic matter (CDOM) within marine systems must be constrained to better assess the impact of CDOM on surface ocean photochemistry and remote sensing of ocean color. Photobleaching, the loss of absorption by CDOM due to light exposure, is the primary sink for marine CDOM. Herein the susceptibility of CDOM to photobleaching by sea surface-level solar radiation was examined in 15 samples collected from wide-ranging open ocean regimes. Samples from the Pacific, Atlantic, Indian and Southern Oceans were irradiated over several days with full-spectrum light under a solar simulator at in situ temperature in order to measure photobleaching rate and derive an empirical matrix, ɛsurf (m-1 μEin-1), which quantifies the effect of surface irradiance on the spectral absorption of CDOM. Irradiation responses among the ocean samples were similar within the ultraviolet (UV) region of the spectrum spanning 300-360 nm, generally exhibiting a decrease in the CDOM absorption coefficient (m-1) and concomitant increase in the CDOM spectral slope parameter, S (nm-1). However, an unexpected irradiation-induced increase in CDOM absorption between approximately 360 and 500 nm was observed for samples from high-nutrient low-chlorophyll (HNLC) environments. This finding was linked to the presence of dissolved nitrate and may explain discrepancies in action spectra for dimethylsulfide (DMS) photobleaching observed between the Equatorial Pacific and Subtropical North Atlantic Oceans. The nitrate-to-phosphate ratio explained 27-70% of observed variability in ɛsurf at observation wavelengths of 330-440 nm, while the initial spectral slope of the samples explained up to 52% of variability in ɛsurf at observation wavelengths of 310-330 nm. These results suggest that the biogeochemical and solar exposure history of the water column, each of which influence the chemical character and thus the spectral quality of CDOM and its photoreactivity, are the

Computing diffuse fraction of global horizontal solar radiation: A model comparison.

PubMed

Dervishi, Sokol; Mahdavi, Ardeshir

2012-06-01

For simulation-based prediction of buildings' energy use or expected gains from building-integrated solar energy systems, information on both direct and diffuse component of solar radiation is necessary. Available measured data are, however, typically restricted to global horizontal irradiance. There have been thus many efforts in the past to develop algorithms for the derivation of the diffuse fraction of solar irradiance. In this context, the present paper compares eight models for estimating diffuse fraction of irradiance based on a database of measured irradiance from Vienna, Austria. These models generally involve mathematical formulations with multiple coefficients whose values are typically valid for a specific location. Subsequent to a first comparison of these eight models, three better performing models were selected for a more detailed analysis. Thereby, the coefficients of the models were modified to account for Vienna data. The results suggest that some models can provide relatively reliable estimations of the diffuse fractions of the global irradiance. The calibration procedure could only slightly improve the models' performance.

Reconstruction of solar UV irradiance since 1974

NASA Astrophysics Data System (ADS)

Krivova, N. A.; Solanki, S. K.; Wenzler, T.; Podlipnik, B.

2009-09-01

Variations of the solar UV irradiance are an important driver of chemical and physical processes in the Earth's upper atmosphere and may also influence global climate. Here we reconstruct solar UV irradiance in the range 115-400 nm over the period 1974-2007 by making use of the recently developed empirical extension of the Spectral And Total Irradiance Reconstruction (SATIRE) models employing Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) data. The evolution of the solar photospheric magnetic flux, which is a central input to the model, is described by the magnetograms and continuum images recorded at the Kitt Peak National Solar Observatory between 1974 and 2003 and by the Michelson Doppler Imager instrument on SOHO since 1996. The reconstruction extends the available observational record by 1.5 solar cycles. The reconstructed Ly-α irradiance agrees well with the composite time series by Woods et al. (2000). The amplitude of the irradiance variations grows with decreasing wavelength and in the wavelength regions of special interest for studies of the Earth's climate (Ly-α and oxygen absorption continuum and bands between 130 and 350 nm) is 1-2 orders of magnitude stronger than in the visible or if integrated over all wavelengths (total solar irradiance).

Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Habte, A.; Andreas, A.; Ottoson, L.

2014-05-01

This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

Analysis of Global Horizontal Irradiance in Version 3 of the National Solar Radiation Database.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, Clifford; Martin, Curtis E.; Guay, Nathan Gene

We report an analysis that compares global horizontal irradiance (GHI) estimates from version 3 of the National Solar Radiation Database (NSRDB v3) with surface measurements of GHI at a wide variety of locations over the period spanning from 2005 to 2012. The NSRDB v3 estimate of GHI are derived from the Physical Solar Model (PSM) which employs physics-based models to estimate GHI from measurements of reflected visible and infrared irradiance collected by Geostationary Operational Environment Satellites (GOES) and several other data sources. Because the ground measurements themselves are uncertain our analysis does not establish the absolute accuracy for PSM GHI.more » However by examining the comparison for trends and for consistency across a large number of sites, we may establish a level of confidence in PSM GHI and identify conditions which indicate opportunities to improve PSM. We focus our evaluation on annual and monthly insolation because these quantities directly relate to prediction of energy production from solar power systems. We find that generally, PSM GHI exhibits a bias towards overestimating insolation, on the order of 5% when all sky conditions are considered, and somewhat less (-3%) when only clear sky conditions are considered. The biases persist across multiple years and are evident at many locations. In our opinion the bias originates with PSM and we view as less credible that the bias stems from calibration drift or soiling of ground instruments. We observe that PSM GHI may significantly underestimate monthly insolation in locations subject to broad snow cover. We found examples of days where PSM GHI apparently misidentified snow cover as clouds, resulting in significant underestimates of GHI during these days and hence leading to substantial understatement of monthly insolation. Analysis of PSM GHI in adjacent pixels shows that the level of agreement between PSM GHI and ground data can vary substantially over distances on the order of 2 km

Trends in Ocean Irradiance using a Radiative Model Forced with Terra Aerosols and Clouds

NASA Technical Reports Server (NTRS)

Gregg, Watson; Casey, Nancy; Romanou, Anastasia

2010-01-01

Aerosol and cloud information from MODIS on Terra provide enhanced capability to understand surface irradiance over the oceans and its variability. These relationships can be important for ocean biology and carbon cycles. An established radiative transfer model, the Ocean-Atmosphere Spectral Irradiance Model (OASIM) is used to describe ocean irradiance variability on seasonal to decadal time scales. The model is forced with information on aerosols and clouds from the MODIS sensor on Terra and Aqua. A 7-year record (2000-2006) showed no trends in global ocean surface irradiance or photosynthetic available irradiance (PAR). There were significant (P<0.05) negative trends in the Mediterranean Sea, tropical Pacific) and tropical Indian Oceans, of -7.0, -5.0 and -2.7 W/sq m respectively. Global interannual variability was also modest. Regional interannual variability was quite large in some ocean basins, where monthly excursions from climatology were often >20 W/sq m. The trends using MODIS data contrast with results from OASIM using liquid water path estimates from the International Satellite Cloud Climatology Project (ISCCP). Here, a global trend of -2 W/sq m was observed, largely dues to a large negative trend in the Antarctic -12 W/sq m. These results suggest the importance of the choice of liquid water path data sets in assessments of medium-length trends in ocean surface irradiance. The choices also impact the evaluation of changes in ocean biogeochemistry.

The Impact of Different Absolute Solar Irradiance Values on Current Climate Model Simulations

NASA Technical Reports Server (NTRS)

Rind, David H.; Lean, Judith L.; Jonas, Jeffrey

2014-01-01

Simulations of the preindustrial and doubled CO2 climates are made with the GISS Global Climate Middle Atmosphere Model 3 using two different estimates of the absolute solar irradiance value: a higher value measured by solar radiometers in the 1990s and a lower value measured recently by the Solar Radiation and Climate Experiment. Each of the model simulations is adjusted to achieve global energy balance; without this adjustment the difference in irradiance produces a global temperature change of 0.48C, comparable to the cooling estimated for the Maunder Minimum. The results indicate that by altering cloud cover the model properly compensates for the different absolute solar irradiance values on a global level when simulating both preindustrial and doubled CO2 climates. On a regional level, the preindustrial climate simulations and the patterns of change with doubled CO2 concentrations are again remarkably similar, but there are some differences. Using a higher absolute solar irradiance value and the requisite cloud cover affects the model's depictions of high-latitude surface air temperature, sea level pressure, and stratospheric ozone, as well as tropical precipitation. In the climate change experiments it leads to an underestimation of North Atlantic warming, reduced precipitation in the tropical western Pacific, and smaller total ozone growth at high northern latitudes. Although significant, these differences are typically modest compared with the magnitude of the regional changes expected for doubled greenhouse gas concentrations. Nevertheless, the model simulations demonstrate that achieving the highest possible fidelity when simulating regional climate change requires that climate models use as input the most accurate (lower) solar irradiance value.

Measurement and modeling of solar irradiance components on horizontal and tilted planes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Padovan, Andrea; Col, Davide del

2010-12-15

In this work new measurements of global and diffuse solar irradiance on the horizontal plane and global irradiance on planes tilted at 20 and 30 oriented due South and at 45 and 65 oriented due East are used to discuss the modeling of solar radiation. Irradiance data are collected in Padova (45.4 N, 11.9 E, 12 m above sea level), Italy. Some diffuse fraction correlations have been selected to model the hourly diffuse radiation on the horizontal plane. The comparison with the present experimental data shows that their prediction accuracy strongly depends on the sky characteristics. The hourly irradiance measurementsmore » taken on the tilted planes are compared with the estimations given by one isotropic and three anisotropic transposition models. The use of an anisotropic model, based on a physical description of the diffuse radiation, provides a much better accuracy, especially when measurements of the diffuse irradiance on the horizontal plane are not available and thus transposition models have to be applied in combination with a diffuse fraction correlation. This is particularly significant for the planes oriented away from South. (author)« less

Radiation-Induced Epigenetic Alterations after Low and High LET Irradiations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aypar, Umut; Morgan, William F.; Baulch, Janet E.

Epigenetics, including DNA methylation and microRNA (miRNA) expression, could be the missing link in understanding the delayed, non-targeted effects of radiation including radiationinduced genomic instability (RIGI). This study tests the hypothesis that irradiation induces epigenetic aberrations, which could eventually lead to RIGI, and that the epigenetic aberrations induced by low linear energy transfer (LET) irradiation are different than those induced by high LET irradiations. GM10115 cells were irradiated with low LET x-rays and high LET iron (Fe) ions and evaluated for DNA damage, cell survival and chromosomal instability. The cells were also evaluated for specific locus methylation of nuclear factor-kappamore » B (NFκB), tumor suppressor in lung cancer 1 (TSLC1) and cadherin 1 (CDH1) gene promoter regions, long interspersed nuclear element 1 (LINE-1) and Alu repeat element methylation, CpG and non-CpG global methylation and miRNA expression levels. Irradiated cells showed increased micronucleus induction and cell killing immediately following exposure, but were chromosomally stable at delayed times post-irradiation. At this same delayed time, alterations in repeat element and global DNA methylation and miRNA expression were observed. Analyses of DNA methylation predominantly showed hypomethylation, however hypermethylation was also observed. MiRNA shown to be altered in expression level after x-ray irradiation are involved in chromatin remodeling and DNA methylation. Different and higher incidence of epigenetic changes were observed after exposure to low LET x-rays than high LET Fe ions even though Fe ions elicited more chromosomal damage and cell killing. This study also shows that the irradiated cells acquire epigenetic changes even though they are chromosomally stable suggesting that epigenetic aberrations may arise in the cell without initiating RIGI.« less

Modelling 1-minute directional observations of the global irradiance.

NASA Astrophysics Data System (ADS)

Thejll, Peter; Pagh Nielsen, Kristian; Andersen, Elsa; Furbo, Simon

2016-04-01

Direct and diffuse irradiances from the sky has been collected at 1-minute intervals for about a year from the experimental station at the Technical University of Denmark for the IEA project "Solar Resource Assessment and Forecasting". These data were gathered by pyrheliometers tracking the Sun, as well as with apertured pyranometers gathering 1/8th and 1/16th of the light from the sky in 45 degree azimuthal ranges pointed around the compass. The data are gathered in order to develop detailed models of the potentially available solar energy and its variations at high temporal resolution in order to gain a more detailed understanding of the solar resource. This is important for a better understanding of the sub-grid scale cloud variation that cannot be resolved with climate and weather models. It is also important for optimizing the operation of active solar energy systems such as photovoltaic plants and thermal solar collector arrays, and for passive solar energy and lighting to buildings. We present regression-based modelling of the observed data, and focus, here, on the statistical properties of the model fits. Using models based on the one hand on what is found in the literature and on physical expectations, and on the other hand on purely statistical models, we find solutions that can explain up to 90% of the variance in global radiation. The models leaning on physical insights include terms for the direct solar radiation, a term for the circum-solar radiation, a diffuse term and a term for the horizon brightening/darkening. The purely statistical model is found using data- and formula-validation approaches picking model expressions from a general catalogue of possible formulae. The method allows nesting of expressions, and the results found are dependent on and heavily constrained by the cross-validation carried out on statistically independent testing and training data-sets. Slightly better fits -- in terms of variance explained -- is found using the purely

Inverse Analysis of Irradiated NuclearMaterial Gamma Spectra via Nonlinear Optimization

NASA Astrophysics Data System (ADS)

Dean, Garrett James

Nuclear forensics is the collection of technical methods used to identify the provenance of nuclear material interdicted outside of regulatory control. Techniques employed in nuclear forensics include optical microscopy, gas chromatography, mass spectrometry, and alpha, beta, and gamma spectrometry. This dissertation focuses on the application of inverse analysis to gamma spectroscopy to estimate the history of pulse irradiated nuclear material. Previous work in this area has (1) utilized destructive analysis techniques to supplement the nondestructive gamma measurements, and (2) been applied to samples composed of spent nuclear fuel with long irradiation and cooling times. Previous analyses have employed local nonlinear solvers, simple empirical models of gamma spectral features, and simple detector models of gamma spectral features. The algorithm described in this dissertation uses a forward model of the irradiation and measurement process within a global nonlinear optimizer to estimate the unknown irradiation history of pulse irradiated nuclear material. The forward model includes a detector response function for photopeaks only. The algorithm uses a novel hybrid global and local search algorithm to quickly estimate the irradiation parameters, including neutron fluence, cooling time and original composition. Sequential, time correlated series of measurements are used to reduce the uncertainty in the estimated irradiation parameters. This algorithm allows for in situ measurements of interdicted irradiated material. The increase in analysis speed comes with a decrease in information that can be determined, but the sample fluence, cooling time, and composition can be determined within minutes of a measurement. Furthermore, pulse irradiated nuclear material has a characteristic feature that irradiation time and flux cannot be independently estimated. The algorithm has been tested against pulse irradiated samples of pure special nuclear material with cooling times of

Solar spectral irradiance variability in cycle 24: observations and models

NASA Astrophysics Data System (ADS)

Marchenko, Sergey V.; DeLand, Matthew T.; Lean, Judith L.

2016-12-01

Utilizing the excellent stability of the Ozone Monitoring Instrument (OMI), we characterize both short-term (solar rotation) and long-term (solar cycle) changes of the solar spectral irradiance (SSI) between 265 and 500 nm during the ongoing cycle 24. We supplement the OMI data with concurrent observations from the Global Ozone Monitoring Experiment-2 (GOME-2) and Solar Radiation and Climate Experiment (SORCE) instruments and find fair-to-excellent, depending on wavelength, agreement among the observations, and predictions of the Naval Research Laboratory Solar Spectral Irradiance (NRLSSI2) and Spectral And Total Irradiance REconstruction for the Satellite era (SATIRE-S) models.

Spatial estimation of sub-hour Global Horizontal Irradiance based on official observations and remote sensors.

PubMed

Gutierrez-Corea, Federico-Vladimir; Manso-Callejo, Miguel-Angel; Moreno-Regidor, María-Pilar; Velasco-Gómez, Jesús

2014-04-11

This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI) observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation) with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images). The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations).

Spatial Estimation of Sub-Hour Global Horizontal Irradiance Based on Official Observations and Remote Sensors

PubMed Central

Gutierrez-Corea, Federico-Vladimir; Manso-Callejo, Miguel-Angel; Moreno-Regidor, María-Pilar; Velasco-Gómez, Jesús

2014-01-01

This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI) observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation) with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images). The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations). PMID:24732102

Comparison of High-Frequency Solar Irradiance: Ground Measured vs. Satellite-Derived

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lave, Matthew; Weekley, Andrew

2016-11-21

High-frequency solar variability is an important to grid integration studies, but ground measurements are scarce. The high resolution irradiance algorithm (HRIA) has the ability to produce 4-sceond resolution global horizontal irradiance (GHI) samples, at locations across North America. However, the HRIA has not been extensively validated. In this work, we evaluate the HRIA against a database of 10 high-frequency ground-based measurements of irradiance. The evaluation focuses on variability-based metrics. This results in a greater understanding of the errors in the HRIA as well as suggestions for improvement to the HRIA.

VIRGO: Experiment for helioseismology and solar irradiance monitoring

NASA Technical Reports Server (NTRS)

Froehlich, Claus; Andersen, Bo N.

1995-01-01

The scientific objectives of the variability of solar irradiance and gravity oscillations (VIRGO) experiment are as follows: to determine the characteristics of pressure and internal gravity oscillations by observing irradiance and radiance variations; to measure the solar total and spectral irradiance, and to quantify their variability. Helioseismological methods can be applied to these data in order to probe the solar interior. Certain convection characteristics and their interaction with magnetic fields will be studied from the results of the irradiance monitoring and from the comparison of the amplitudes and phases of the oscillations as observed from the brightness by VIRGO and from velocity by the global oscillations at low frequency (GOLF) experiment. The VIRGO experiment contains two active-cavity radiometers that monitor the solar constant, two three-channel sunphotometers that measure the spectral irradiance, and a low resolution imager with 12 pixels that measures the radiance distribution over the solar disk at 500 nm. The scientific objectives of VIRGO are presented, the instruments and the data acquisition and control system are described, and their measured performances are given.

The Thermal Regulation of Gravitational Instabilities in Protoplanetary Disks. IV. Simulations with Envelope Irradiation

NASA Astrophysics Data System (ADS)

Cai, Kai; Durisen, Richard H.; Boley, Aaron C.; Pickett, Megan K.; Mejía, Annie C.

2008-02-01

It is generally thought that protoplanetary disks embedded in envelopes are more massive and thus more susceptible to gravitational instabilities (GIs) than exposed disks. We present three-dimensional radiative hydrodynamic simulations of protoplanetary disks with the presence of envelope irradiation. For a disk with a radius of 40 AU and a mass of 0.07 M⊙ around a young star of 0.5 M⊙, envelope irradiation tends to weaken and even suppress GIs as the irradiating flux is increased. The global mass transport induced by GIs is dominated by lower order modes, and irradiation preferentially suppresses higher order modes. As a result, gravitational torques and mass inflow rates are actually increased by mild irradiation. None of the simulations produce dense clumps or rapid cooling by convection, arguing against direct formation of giant planets by disk instability, at least in irradiated disks. However, dense gas rings and radial mass concentrations are produced, and these might be conducive to accelerated planetary core formation. Preliminary results from a simulation of a massive embedded disk with physical characteristics similar to one of the disks in the embedded source L1551 IRS 5 indicate a long radiative cooling time and no fragmentation. The GIs in this disk are dominated by global two- and three-armed modes.

Estimations of the Global Distribution and Time Series of UV Noontime Irradiance (305, 310, 324, 380 nm, and Erythemal) from TOMS and SeaWiFS Data

NASA Technical Reports Server (NTRS)

Herman, J.

2004-01-01

The amount of UV irradiance reaching the Earth's surface is estimated from the measured cloud reflectivity, ozone, aerosol amounts, and surface reflectivity time series from 1980 to 1992 and 1997 to 2000 to estimate changes that have occurred over a 21-year period. Recent analysis of the TOMS data shows that there has been an apparent increase in reflectivity (decrease in W) in the Southern Hemisphere that is related to a calibration error in EP-TOMS. Data from the well-calibrated SeaWiFS satellite instrument have been used to correct the EP-TOMS reflectivity and UV time series. After correction, some of the local trend features seen in the N7 time series (1980 to 1992) have been continued in the combined time series, but the overall zonal average and global trends have changed. In addition to correcting the EP-TOMS radiance calibration, the use of SeaWiFS cloud data permits estimation of UV irradiance at higher spatial resolution (1 to 4 km) than is available from TOMS (100 km) under the assumption that ozone is slowly varying over a scale of 100 km. The key results include a continuing decrease in cloud cover over Europe and North America with a corresponding increase in UV and a decrease in UV irradiance near Antarctica.

A reconstruction of solar irradiance using a flux transport model

NASA Astrophysics Data System (ADS)

Dasi Espuig, Maria; Krivova, Natalie; Solanki, Sami K.; Jiang, Jie

2012-07-01

Solar irradiance is one of the important drivers of the Earth's global climate, but it has only been measured for the past 33 years. Its reconstructions are therefore crucial to study longer term variations relevant to climate timescales. Most successful in reproducing the measured irradiance variations have being the models that are based on the assumption that irradiance changes are caused by the evolution of the photospheric magnetic field. Our SATIRE-S model is one of these, which uses solar full-disc magnetograms as an input, and these are available for less than four decades. To reconstruct the irradiance back to times when no observed magnetograms are available, we combine the SATIRE-S model with synthetic magnetograms, produced using a surface flux transport model. The model is fed with daily, observed or modelled statistically, records of sunspot positions, areas, and tilt angles. The concept of overlapping ephemeral region cycles is used to describe the secular change in the irradiance.

A New method for identifying possible causal relationships between CO2, total solar irradiance and global temperature change

NASA Astrophysics Data System (ADS)

Seip, Knut L.; Grøn, Øyvind

2017-02-01

We apply a novel method based upon "before" and "after" relationships to investigate and quantify interconnections between global temperature anomaly (GTA), as response variable, and greenhouse gases (CO2) and total solar irradiance (TSI) as candidate causal variables for the period 1880 to 2010. The most likely interpretations of our results for the 6 to 8 years cyclic components of the variables are that during the period 1929 to 1936, CO2 significantly leads GTA. However, during the period 1960-2003, GTA apparently leads CO2, that is, the peaks (and troughs) in GTA are in front of, and close to, the peaks (and troughs) in CO2. For time windows outside these periods, we did not find significant before or after-relations. An alternative interpretation is that there is a shift between short (≈1.5 year) and long (≈5 years) durations between cause and effect. Relationships between GTA and TSI suggest that "inertia" of the global sea, land, and atmosphere system leads to delays longer than half their common cycle length of about 10 years. Based on the interaction patterns between the variables GTA, CO2, and TSI, we suggest the possibility that a new regime for how the variables interact started around 1960. From trend forms, and not considering physical mechanisms, we found that the trend in CO2 contributes ≈ 90 %, and the trend in TSI ≈ 10 %, to the trend in GTA during the last 130 years.

Decadal changes in shortwave irradiance at the surface in the period from 1960 to 2000 estimated from Global Energy Balance Archive Data

NASA Astrophysics Data System (ADS)

Gilgen, H.; Roesch, A.; Wild, M.; Ohmura, A.

2009-05-01

Decadal changes in shortwave irradiance at the Earth's surface are estimated for the period from approximately 1960 through to 2000 from pyranometer records stored in the Global Energy Balance Archive. For this observational period, estimates could be calculated for a total of 140 cells of the International Satellite Cloud Climatology Project grid (an equal area 2.5° × 2.5° grid at the equator) using regression models allowing for station effects. In large regions worldwide, shortwave irradiance decreases in the first half of the observational period, recovers from the decrease in the 1980s, and thereafter increases, in line with previous reports. Years of trend reversals are determined for the grid cells which are best described with a second-order polynomial model. This reversal of the trend is observed in the majority of the grid cells in the interior of Europe and in Japan. In China, shortwave irradiance recovers during the 1990s in the majority of the grid cells in the southeast and northeast from the decrease observed in the period from 1960 through to 1990. A reversal of the trend in the 1980s or early 1990s is also observed for two grid cells in North America, and for the grid cells containing the Kuala Lumpur (Malaysia), Singapore, Casablanca (Morocco), Valparaiso (Chile) sites, and, noticeably, the remote South Pole and American Samoa sites. Negative trends persist, i.e., shortwave radiation decreases, for the observational period 1960 through to 2000 at the European coasts, in central and northwest China, and for three grid cells in India and two in Africa.

Reconstruction of daily solar UV irradiation from 1893 to 2002 in Potsdam, Germany

NASA Astrophysics Data System (ADS)

Junk, Jürgen; Feister, Uwe; Helbig, Alfred

2007-08-01

Long-term records of solar UV radiation reaching the Earth’s surface are scarce. Radiative transfer calculations and statistical models are two options used to reconstruct decadal changes in solar UV radiation from long-term records of measured atmospheric parameters that contain information on the effect of clouds, atmospheric aerosols and ground albedo on UV radiation. Based on earlier studies, where the long-term variation of daily solar UV irradiation was derived from measured global and diffuse irradiation as well as atmospheric ozone by a non-linear regression method [Feister et al. (2002) Photochem Photobiol 76:281 293], we present another approach for the reconstruction of time series of solar UV radiation. An artificial neural network (ANN) was trained with measurements of solar UV irradiation taken at the Meteorological Observatory in Potsdam, Germany, as well as measured parameters with long-term records such as global and diffuse radiation, sunshine duration, horizontal visibility and column ozone. This study is focussed on the reconstruction of daily broad-band UV-B (280 315 nm), UV-A (315 400 nm) and erythemal UV irradiation (ER). Due to the rapid changes in cloudiness at mid-latitude sites, solar UV irradiance exhibits appreciable short-term variability. One of the main advantages of the statistical method is that it uses doses of highly variable input parameters calculated from individual spot measurements taken at short time intervals, which thus do represent the short-term variability of solar irradiance.

White Paper on SBUV/2 Solar Irradiance Measurements

NASA Technical Reports Server (NTRS)

Hilsenrath, Ernest; DeLand, Matthew T.; Cebula, Richard P.

1996-01-01

The importance of solar irradiance measurements by the Solar Backscatter Ultraviolet, Model 2 (SBUV/2) instruments on NOAA's operational satellites is described. These measurements are necessary accurately monitor the long-term changes in the global column ozone amount, the altitude distribution of ozone in the upper stratosphere, and the degree to which ozone changes are caused by anthropogenic sources. Needed to accomplish these goals are weekly solar irradiance measurements at the operational ozone wavelengths, daily measurements of the Mg II proxy index, instrument-specific Mg II scale factors, and daily measurements of the solar spectral irradiance at photochemically important wavelengths. Two solar measurement schedules are provided: (1) a baseline schedule for all instruments except the NOAA-14 instrument and (2) a modified schedule for the NOAA-14 SBUV/2 instrument. This latter schedule is needed due to the NOAA-14 grating drive problems.

Solar Spectral Irradiance Variability in Cycle 24: Model Predictions and OMI Observations

NASA Technical Reports Server (NTRS)

Marchenko, S.; DeLand, M.; Lean, J.

2016-01-01

Utilizing the excellent stability of the Ozone Monitoring Instrument (OMI), we characterize both short-term (solar rotation) and long-term (solar cycle) changes of the solar spectral irradiance (SSI) between 265-500 nanometers during the ongoing Cycle 24. We supplement the OMI data with concurrent observations from the GOME-2 (Global Ozone Monitoring Experiment - 2) and SORCE (Solar Radiation and Climate Experiment) instruments and find fair-to-excellent agreement between the observations and predictions of the NRLSSI2 (Naval Research Laboratory Solar Spectral Irradiance - post SORCE) and SATIRE-S (the Naval Research Laboratory's Spectral And Total Irradiance REconstruction for the Satellite era) models.

Dysfonctionnements radio-induits du transport colique chez le rat

NASA Astrophysics Data System (ADS)

François, A.; Lebrun, F.; Ksas, B.; Aigueperse, J.; Gourmelon, P.; MacNaughton, W. K.; Griffiths, N. M.

1998-04-01

The symptom commonly associated with whole body irradiation is diarrhoea, a still quite obscure phenomenon, which leads to decreased chance of cure of irradiated people. The aim of this study was to provide evidence for dysfunction of intestinal water and electrolyte transport regulation by the enteric nervous system after exposure to ionising radiation. This study shows decreased capacity of enteric nervous system to influence colonic transport 3days after irradiation, correlated to a diminished response to a neurotransmitter: serotonin. Radio-induced diarrhea may result from epithelial structural injury but also from impaired regulatory processes of intestinal transport. L'un des symptômes majeurs d'une irradiation corporelle totale ou abdominale est l'apparition de diarrhées, dont les causes sont encore mal connues, et qui mettent en jeu le pronostique vital de l'individu irradié. Cette étude vise à mettre en évidence l'atteinte de la régulation du transport intestinal d'eau et d'électrolytes par les rayonnements ionisants. On observe une diminution de la capacité du système nerveux entérique à influencer le transport colique 3jours après irradiation, corrélée à une diminution de la réponse épithéliale à un neurotransmetteur : la sérotonine. Les diarrhées radio-induites résulteraient d'une atteinte structurelle de l'épithélium mais également des processus de régulation du transport intestinal.

Status of FeCrAl ODS Irradiations in the High Flux Isotope Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Field, Kevin G.; Howard, Richard H.

2016-08-19

FeCrAl oxide-dispersion strengthened (ODS) alloys are an attractive sub-set alloy class of the more global FeCrAl material class for nuclear applications due to their high-temperature steam oxidation resistance and hypothesized enhanced radiation tolerance. A need currently exists to determine the radiation tolerance of these newly developed alloys. To address this need, a preliminary study was conducted using the High Flux Isotope Reactor (HFIR) to irradiate an early generation FeCrAl ODS alloy, 125YF. Preliminary post-irradiation examination (PIE) on these irradiated specimens have shown good radiation tolerance at elevated temperatures (≥330°C) but possible radiation-induced hardening and embrittlement at irradiations of 200°C tomore » a damage level of 1.9 displacement per atom (dpa). Building on this experience, a new series of irradiations are currently being conceptualized. This irradiation series called the FCAD irradiation program will irradiate the latest generation FeCrAl ODS and FeCr ODS alloys to significantly higher doses. These experiments will provide the necessary information to determine the mechanical performance of irradiated FeCrAl ODS alloys at light water reactor and fast reactor conditions.« less

A semiparametric spatio-temporal model for solar irradiance data

DOE PAGES

Patrick, Joshua D.; Harvill, Jane L.; Hansen, Clifford W.

2016-03-01

Here, we evaluate semiparametric spatio-temporal models for global horizontal irradiance at high spatial and temporal resolution. These models represent the spatial domain as a lattice and are capable of predicting irradiance at lattice points, given data measured at other lattice points. Using data from a 1.2 MW PV plant located in Lanai, Hawaii, we show that a semiparametric model can be more accurate than simple interpolation between sensor locations. We investigate spatio-temporal models with separable and nonseparable covariance structures and find no evidence to support assuming a separable covariance structure. These results indicate a promising approach for modeling irradiance atmore » high spatial resolution consistent with available ground-based measurements. Moreover, this kind of modeling may find application in design, valuation, and operation of fleets of utility-scale photovoltaic power systems.« less

Models of Solar Irradiance Variability and the Instrumental Temperature Record

NASA Technical Reports Server (NTRS)

Marcus, S. L.; Ghil, M.; Ide, K.

1998-01-01

The effects of decade-to-century (Dec-Cen) variations in total solar irradiance (TSI) on global mean surface temperature Ts during the pre-Pinatubo instrumental era (1854-1991) are studied by using two different proxies for TSI and a simplified version of the IPCC climate model.

Solar Spectral Irradiance and Climate

NASA Technical Reports Server (NTRS)

Pilewskie, P.; Woods, T.; Cahalan, R.

2012-01-01

Spectrally resolved solar irradiance is recognized as being increasingly important to improving our understanding of the manner in which the Sun influences climate. There is strong empirical evidence linking total solar irradiance to surface temperature trends - even though the Sun has likely made only a small contribution to the last half-century's global temperature anomaly - but the amplitudes cannot be explained by direct solar heating alone. The wavelength and height dependence of solar radiation deposition, for example, ozone absorption in the stratosphere, absorption in the ocean mixed layer, and water vapor absorption in the lower troposphere, contribute to the "top-down" and "bottom-up" mechanisms that have been proposed as possible amplifiers of the solar signal. New observations and models of solar spectral irradiance are needed to study these processes and to quantify their impacts on climate. Some of the most recent observations of solar spectral variability from the mid-ultraviolet to the near-infrared have revealed some unexpected behavior that was not anticipated prior to their measurement, based on an understanding from model reconstructions. The atmospheric response to the observed spectral variability, as quantified in climate model simulations, have revealed similarly surprising and in some cases, conflicting results. This talk will provide an overview on the state of our understanding of the spectrally resolved solar irradiance, its variability over many time scales, potential climate impacts, and finally, a discussion on what is required for improving our understanding of Sun-climate connections, including a look forward to future observations.

CMSAF products Cloud Fraction Coverage and Cloud Type used for solar global irradiance estimation

NASA Astrophysics Data System (ADS)

Badescu, Viorel; Dumitrescu, Alexandru

2016-08-01

Two products provided by the climate monitoring satellite application facility (CMSAF) are the instantaneous Cloud Fractional Coverage (iCFC) and the instantaneous Cloud Type (iCTY) products. Previous studies based on the iCFC product show that the simple solar radiation models belonging to the cloudiness index class n CFC = 0.1-1.0 have rRMSE values ranging between 68 and 71 %. The products iCFC and iCTY are used here to develop simple models providing hourly estimates for solar global irradiance. Measurements performed at five weather stations of Romania (South-Eastern Europe) are used. Two three-class characterizations of the state-of-the-sky, based on the iCTY product, are defined. In case of the first new sky state classification, which is roughly related with cloud altitude, the solar radiation models proposed here perform worst for the iCTY class 4-15, with rRMSE values ranging between 46 and 57 %. The spreading error of the simple models is lower than that of the MAGIC model for the iCTY classes 1-4 and 15-19, but larger for iCTY classes 4-15. In case of the second new sky state classification, which takes into account in a weighted manner the chance for the sun to be covered by different types of clouds, the solar radiation models proposed here perform worst for the cloudiness index class n CTY = 0.7-0.1, with rRMSE values ranging between 51 and 66 %. Therefore, the two new sky state classifications based on the iCTY product are useful in increasing the accuracy of solar radiation models.

Optimizing UV Index determination from broadband irradiances

NASA Astrophysics Data System (ADS)

Tereszchuk, Keith A.; Rochon, Yves J.; McLinden, Chris A.; Vaillancourt, Paul A.

2018-03-01

A study was undertaken to improve upon the prognosticative capability of Environment and Climate Change Canada's (ECCC) UV Index forecast model. An aspect of that work, and the topic of this communication, was to investigate the use of the four UV broadband surface irradiance fields generated by ECCC's Global Environmental Multiscale (GEM) numerical prediction model to determine the UV Index. The basis of the investigation involves the creation of a suite of routines which employ high-spectral-resolution radiative transfer code developed to calculate UV Index fields from GEM forecasts. These routines employ a modified version of the Cloud-J v7.4 radiative transfer model, which integrates GEM output to produce high-spectral-resolution surface irradiance fields. The output generated using the high-resolution radiative transfer code served to verify and calibrate GEM broadband surface irradiances under clear-sky conditions and their use in providing the UV Index. A subsequent comparison of irradiances and UV Index under cloudy conditions was also performed. Linear correlation agreement of surface irradiances from the two models for each of the two higher UV bands covering 310.70-330.0 and 330.03-400.00 nm is typically greater than 95 % for clear-sky conditions with associated root-mean-square relative errors of 6.4 and 4.0 %. However, underestimations of clear-sky GEM irradiances were found on the order of ˜ 30-50 % for the 294.12-310.70 nm band and by a factor of ˜ 30 for the 280.11-294.12 nm band. This underestimation can be significant for UV Index determination but would not impact weather forecasting. Corresponding empirical adjustments were applied to the broadband irradiances now giving a correlation coefficient of unity. From these, a least-squares fitting was derived for the calculation of the UV Index. The resultant differences in UV indices from the high-spectral-resolution irradiances and the resultant GEM broadband irradiances are typically within 0

Progress Towards Deriving an Improved Long-Term Global Solar Resource

NASA Technical Reports Server (NTRS)

Cox, Stephen J.; Mikovitz, J. Colleen; Zhang, Taiping; Sorlie, Susan; Stackhouse, Paul W., Jr.; Perez, Richard; Hemker, Karl, Jr.; Schlemmer, James; Kivalov, Sergey; Renne, David;

ATF Neutron Irradiation Program Irradiation Vehicle Design Concepts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geringer, J. W.; Katoh, Yutai; Howard, Richard H.

The Japan Atomic Energy Agency (JAEA) under the Civil Nuclear Energy Working Group (CNWG) is engaged in a cooperative research effort with the U.S. Department of Energy (DOE) to explore issues related to nuclear energy, including research on accident-tolerant fuels and materials for use in light water reactors. This work develops a draft technical plan for a neutron irradiation program on the candidate accident-tolerant fuel cladding materials and elements using the High Flux Isotope Reactor (HFIR). The research program requires the design of a detailed experiment, development of test vehicles, irradiation of test specimens, possible post irradiation examination and characterizationmore » of irradiated materials and the shipment of irradiated materials to Japan. This report discusses the conceptual design, the development and irradiation of the test vehicles.« less

Evaluation of solar irradiance models for climate studies

NASA Astrophysics Data System (ADS)

Ball, William; Yeo, Kok-Leng; Krivova, Natalie; Solanki, Sami; Unruh, Yvonne; Morrill, Jeff

2015-04-01

Instruments on satellites have been observing both Total Solar Irradiance (TSI) and Spectral Solar Irradiance (SSI), mainly in the ultraviolet (UV), since 1978. Models were developed to reproduce the observed variability and to compute the variability at wavelengths that were not observed or had an uncertainty too high to determine an accurate rotational or solar cycle variability. However, various models and measurements show different solar cycle SSI variability that lead to different modelled responses of ozone and temperature in the stratosphere, mainly due to the different UV variability in each model, and the global energy balance. The NRLSSI and SATIRE-S models are the most comprehensive reconstructions of solar irradiance variability for the period from 1978 to the present day. But while NRLSSI and SATIRE-S show similar solar cycle variability below 250 nm, between 250 and 400 nm SATIRE-S typically displays 50% larger variability, which is however, still significantly less then suggested by recent SORCE data. Due to large uncertainties and inconsistencies in some observational datasets, it is difficult to determine in a simple way which model is likely to be closer to the true solar variability. We review solar irradiance variability measurements and modelling and employ new analysis that sheds light on the causes of the discrepancies between the two models and with the observations.

Global Increase in UV Irradiance during the Past 30 Years (1979-2008) Estimated from Satellite Data

NASA Technical Reports Server (NTRS)

Herman, Jay R.

2010-01-01

Zonal average ultraviolet irradiance (flux ultraviolet, F(sub uv)) reaching the Earth's surface has significantly increased since 1979 at all latitudes except the equatorial zone. Changes are estimated in zonal average F(sub uv) caused by ozone and cloud plus aerosol reflectivity using an approach based on Beer's law for monochromatic and action spectrum weighted irradiances. For four different cases, it is shown that Beer's Law leads to a power law form similar to that applied to erythemal action spectrum weighted irradiances. Zonal and annual average increases in F(sub uv) were caused by decreases in ozone amount from 1979 to 1998. After 1998, midlatitude annual average ozone amounts and UV irradiance levels have been approximately constant. In the Southern Hemisphere, zonal and annual average UV increase is partially offset by tropospheric cloud and aerosol transmission decreases (hemispherical dimming), and to a lesser extent in the Northern Hemisphere. Ozone and 340 nm reflectivity changes have been obtained from multiple joined satellite time series from 1978 to 2008. The largest zonal average increases in F(sub uv) have occurred in the Southern Hemisphere. For clear-sky conditions at 50 S, zonal average F(sub uv) changes are estimated (305 nm, 23%; erythemal, 8.5%; 310 nm, 10%; vitamin D production, 12%). These are larger than at 50 N (305 nm, 9%; erythemal, 4%; 310 nm, 4%; vitamin D production, 6%). At the latitude of Buenos Aires, Argentina (34.6 S), the clear-sky Fuv increases are comparable to the increases near Washington, D. C. (38.9 N): 305 nm, 9% and 7%; erythemal, 6% and 4%; and vitamin D production, 7% and 5%, respectively.

The NASA POWER SSE: Deriving the Direct Normal Counterpart from the CERES SYN1deg Hourly Global Horizontal Irradiance during Early 2000 to Near Present

NASA Astrophysics Data System (ADS)

Zhang, T.; Stackhouse, P. W., Jr.; Westberg, D. J.

2017-12-01

The NASA Prediction of Worldwide Energy Resource (POWER) Surface meteorology and Solar Energy (SSE) provides solar direct normal irradiance (DNI) data as well as a variety of other solar parameters. The currently available DNIs are monthly means on a quasi-equal-area grid system with grid boxes roughly equivalent to 1 degree longitude by 1 degree latitude around the equator from July 1983 to June 2005, and the data were derived from the GEWEX Surface Radiation Budget (SRB) monthly mean global horizontal irradiance (GHI, Release 3) and regression analysis of the Baseline Surface Radiation Network (BSRN) data. To improve the quality of the DNI data and push the temporal coverage of the data to near present, we have applied a modified version of the DIRINDEX global-to-beam model to the GEWEX SRB (Release 3) all-sky and clear-sky 3-hourly GHI data and derived their DNI counterparts for the period from July 1983 to December 2007. The results have been validated against the BSRN data. To further expand the data in time to near present, we are now applying the DIRINDEX model to the Clouds and the Earth's Radiant Energy System (CERES) data. The CERES SYN1deg (Edition 4A) offers hourly all-sky and clear-sky GHIs on a 1 degree longitude by 1 degree latitude grid system from March 2000 to October 2016 as of this writing. Comparisons of the GHIs with their BSRN counterparts show remarkable agreements. Besides the GHIs, the inputs will also include the atmospheric water vapor and surface pressure from the Modern Era Retrospective-Analysis for Research and Applications (MERRA) and the aerosol optical depth from the Max-Planck Institute Climatology (MAC-v1). Based on the performance of the DIRINDEX model with the GEWEX SRB GHI data, we expect at least equally good or even better results. In this paper, we will show the derived hourly, daily, and monthly mean DNIs from the CERES SYN1deg hourly GHIs from March 2000 to October 2016 and how they compare with the BSRN data.

Status of Post Irradiation Examination of FCAB and FCAT Irradiation Capsules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Field, Kevin G.; Yamamoto, Yukinori; Howard, Richard H.

A series of irradiation programs are ongoing to address the need for determining the radiation tolerance of FeCrAl alloys. These irradiation programs, deemed the FCAT and FCAB irradiation programs, use the High Flux Isotope Reactor (HFIR) to irradiate second generation wrought FeCrAl alloys and early-generation powder-metallurgy (PM) oxide dispersion-strengthened (ODS) FeCrAl alloys. Irradiations have been or are being performed at temperatures of 200°C, 330°C, and 550°C from doses of 1.8 dpa up to 16 dpa. Preliminary post-irradiation examination (PIE) on low dose (<2 dpa) irradiation capsules of tensile specimens has been performed. Analysis of co-irradiated SiC thermometry have shown reasonablemore » matching between the nominal irradiation temperatures and the target irradiation temperatures. Room temperature tensile tests have shown typical radiation-induced hardening and embrittlement at irradiations of 200°C and 330°C, but a propensity for softening when irradiated to 550°C for the wrought alloys. The PM-ODS FeCrAl specimens showed less hardening compared to the wrought alloys. Future PIE includes high temperature tensile tests on the low dose irradiation capsules as well as the determination of reference fracture toughness transition temperature, T o, in alloys irradiated to 7 dpa and higher.« less

Downward solar global irradiance at the surface in São Paulo city—The climatological effects of aerosol and clouds

NASA Astrophysics Data System (ADS)

Yamasoe, M. A.; do Rosário, N. M. E.; Barros, K. M.

2017-01-01

We analyzed the variability of downward solar irradiance reaching the surface at São Paulo city, Brazil, and estimated the climatological aerosol and cloud radiative effects. Eleven years of irradiance were analyzed, from 2005 to 2015. To distinguish the aerosol from the cloud effect, the radiative transfer code LibRadtran was used to calculate downward solar irradiance. Two runs were performed, one considering only ozone and water vapor daily variability, with AOD set to zero and the second allowing the three variables to change, according to mean climatological values. The difference of the 24 h mean irradiance calculated with and without aerosol resulted in the shortwave aerosol direct radiative effect, while the difference between the measured and calculated, including the aerosol, represented the cloud effect. Results showed that, climatologically, clouds can be 4 times more effective than aerosols. The cloud shortwave radiative effect presented a maximum reduction of about -170 W m-2 in January and a minimum in July, of -37 W m-2. The aerosol direct radiative effect was maximum in spring, when the transport of smoke from the Amazon and central parts of South America is frequent toward São Paulo. Around mid-September, the 24 h radiative effect due to aerosol only was estimated to be -50 W m-2. Throughout the rest of the year, the mean aerosol effect was around -20 W m-2 and was attributed to local urban sources. The effect of the cloud fraction on the cloud modification factor, defined as the ratio of all-sky irradiation to cloudless sky irradiation, showed dependence on the cloud height. Low clouds presented the highest impact while the presence of high clouds only almost did not affect solar transmittance, even in overcast conditions.

Characterization of Irradiated and Non-Irradiated Rubber from Automotive Scrap Tires

NASA Astrophysics Data System (ADS)

Souza, Clécia Moura; Silva, Leonardo G.

The aim of this work was to characterize the samples of irradiated and non-irradiated rubber from automotive scrap tires. Rubber samples from scrap tires were irradiated at irradiation doses of 200, 400 and 600kGy in an electron beam accelerator. Subsequently, both the irradiated and non-irradiated samples were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, and Fourier transform infrared (FTIR) spectrophotometry.

Development of AM 1.5 global measurement procedures and international cell measurement round robin

NASA Technical Reports Server (NTRS)

Mueller, R.

1985-01-01

The development of the capability for measurement under global irradiance spectral distribution is reported. The airmass 1.5 global measurement procedure is given. Also given is the procedure and justification for using the large area pulsed solar simulator (LAPSS). The status of the international round robin of reference cell measurements managed by the Commission of European Communities (CEC) is described.

Rapid differentiation between gamma-irradiated and non irradiated potato tubers

NASA Astrophysics Data System (ADS)

Jona, Roberto; Fronda, Anna

The use of gamma irradiation as commercial method for the preservation of fruits and vegetables calls for methods of differentiation between irradiated and non-irradiated foodstuffs. In a previous research, the polysaccharidic content of cell walls of irradiated tissue has been investigated, but it required rather long time to reach the result. A method devised to ascertain the vitality of cells has been applied to distinguish irradiated from non-irradiated potato tubers. 500 mg of tissue excised from tubers have been infiltrated with tetrazolium chloride 0.6% in phosphate buffer, pH 7.4. After 15 hrs of incubation at 30°C the treated tissues have been extracted with 95% ethanol whose O.D. has been measured at 530 mμ wavelength. The colour intensity of the alcohol allowed a very clearcut recognition of the irradiated tubers.

Imaging Fourier Transform Spectroscopy of the Boundary Layer Plume from Laser Irradiated Polymers and Carbon Materials

DTIC Science & Technology

2014-06-16

with surface desorption of the monomer. For laser-irradiated porous graphite targets, experimental results indicated a dominant CO2 production at...global models [78, 79, 87-89]. For simplicity, established global kinetics are considered and compare with experimental results obtained from IFTS...investigated up to 3 mm away from the surface into the boundary layer. At 0.72 mm from the surface, experimental results indicated a dominant production of

Comparison of Irradiation and Wolbachia Based Approaches for Sterile-Male Strategies Targeting Aedes albopictus

PubMed Central

Atyame, Célestine M.; Labbé, Pierrick; Lebon, Cyrille; Weill, Mylène; Moretti, Riccardo; Marini, Francesca; Gouagna, Louis Clément; Calvitti, Maurizio; Tortosa, Pablo

2016-01-01

The global expansion of Aedes albopictus together with the absence of vaccines for most of the arboviruses transmitted by this mosquito has stimulated the development of sterile-male strategies aiming at controlling disease transmission through the suppression of natural vector populations. In this context, two environmentally friendly control strategies, namely the Sterile Insect Technique (SIT) and the Wolbachia-based Incompatible Insect Technique (IIT) are currently being developed in several laboratories worldwide. So far however, there is a lack of comparative assessment of these strategies under the same controlled conditions. Here, we compared the mating capacities, i.e. insemination capacity, sterilization capacity and mating competitiveness of irradiated (35 Gy) and incompatible Ae. albopictus males at different ages and ratios under laboratory controlled conditions. Our data show that there was no significant difference in insemination capacity of irradiated and incompatible males, both male types showing lower capacities than untreated males at 1 day but recovering full capacity within 5 days following emergence. Regarding mating competitiveness trials, a global observed trend is that incompatible males tend to induce a lower hatching rate than irradiated males in cage controlled confrontations. More specifically, incompatible males were found more competitive than irradiated males in 5:1 ratio regardless of age, while irradiated males were only found more competitive than incompatible males in the 1:1 ratio at 10 days old. Overall, under the tested conditions, IIT seemed to be slightly more effective than SIT. However, considering that a single strategy will likely not be adapted to all environments, our data stimulates the need for comparative assessments of distinct strategies in up-scaled conditions in order to identify the most suitable and safe sterilizing technology to be implemented in a specific environmental setting and to identify the

Image irradiance distribution in the 3MI wide field of view polarimeter

NASA Astrophysics Data System (ADS)

Gabrieli, Riccardo; Bartoli, Alessandro; Maiorano, Michele; Bruno, Umberto; Olivieri, Monica; Calamai, Luciano; Manolis, Ilias; Labate, Demetrio

2015-09-01

The Multi-Viewing, Multi-Channel, Multi-Polarisation Imager (3MI) is an imaging radiometer for the ESA/Eumetsat MeteOp-SG programme. Based on the heritage of the POLDER/PARASOL instrument, 3MI is designed to collect global observations of the top-of-atmosphere polarised bi-directional reflectance distribution function in 12 spectral bands, by observing the same target from multiple views using a pushbroom scanning concept. The demanding challenge of the 3MI optical design is represented by the polarisation and image irradiance fall-off (throughput uniformity) requirements. In a generic optical system, the image irradiance fall-off is a function of: target radiance distribution and polarisation, entrance pupil size and optical transmittance variations across the field of view (FOV), distortion and vignetting. In most applications these aspects can be considered as independent; however, when high image irradiance uniformity is required, they have to be considered as linked together. This is particularly true in case of a wide FOV polarimeter as 3MI is. In order to properly account for these aspects, an irradiance fall-off analytical model has been developed in the frame of 3MI Optics Pre-Development (OPD), whose aim is to mitigate any technological risks associated with the 3MI instrument development. It is shown how it is possible to control the image irradiance distribution acting on optical design parameters (e.g. distortion and entrance pupil size variation with FOV). Moreover, the impact of polarisation performances on irradiance fall-off is discussed.

Quality assessment of solar UV irradiance measured with array spectroradiometers

NASA Astrophysics Data System (ADS)

Egli, Luca; Gröbner, Julian; Hülsen, Gregor; Bachmann, Luciano; Blumthaler, Mario; Dubard, Jimmy; Khazova, Marina; Kift, Richard; Hoogendijk, Kees; Serrano, Antonio; Smedley, Andrew; Vilaplana, José-Manuel

2016-04-01

The reliable quantification of ultraviolet (UV) radiation at the earth's surface requires accurate measurements of spectral global solar UV irradiance in order to determine the UV exposure to human skin and to understand long-term trends in this parameter. Array spectroradiometers (ASRMs) are small, light, robust and cost-effective instruments, and are increasingly used for spectral irradiance measurements. Within the European EMRP ENV03 project "Solar UV", new devices, guidelines and characterization methods have been developed to improve solar UV measurements with ASRMs, and support to the end user community has been provided. In order to assess the quality of 14 end user ASRMs, a solar UV intercomparison was held on the measurement platform of the World Radiation Center (PMOD/WRC) in Davos, Switzerland, from 10 to 17 July 2014. The results of the blind intercomparison revealed that ASRMs, currently used for solar UV measurements, show a large variation in the quality of their solar UV measurements. Most of the instruments overestimate the erythema-weighted UV index - in particular at large solar zenith angles - due to stray light contribution in the UV-B range. The spectral analysis of global solar UV irradiance further supported the finding that the uncertainties in the UV-B range are very large due to stray light contribution in this wavelength range. In summary, the UV index may be detected by some commercially available ASRMs within 5 % compared to the world reference spectroradiometer, if well characterized and calibrated, but only for a limited range of solar zenith angles. Generally, the tested instruments are not yet suitable for solar UV measurements for the entire range between 290 and 400 nm under all atmospheric conditions.

Quality assessment of solar UV irradiance measured with array spectroradiometers

NASA Astrophysics Data System (ADS)

Egli, L.; Gröbner, J.; Hülsen, G.; Bachmann, L.; Blumthaler, M.; Dubard, J.; Khazova, M.; Kift, R.; Hoogendijk, K.; Serrano, A.; Smedley, A. R. D.; Vilaplana, J.-M.

2015-12-01

The reliable quantification of ultraviolet (UV) radiation at the Earth's surface requires accurate measurements of spectral global solar UV irradiance in order to determine the UV exposure to human skin and to understand long-term trends in this parameter. Array spectroradiometers are small, light, robust and cost effective instruments and are increasingly used for spectral irradiance measurements. Within the European EMRP-ENV03 project "Solar UV", new devices, guidelines, and characterization methods have been developed to improve solar UV measurements with array spectroradiometers and support to the end-user community has been provided. In order to assess the quality of 14 end-user array spectroradiometers, a solar UV intercomparison was held on the measurement platform of the World Radiation Center (PMOD/WRC) in Davos, Switzerland, from 10 to 17 July 2014. The results of the intercomparison revealed that array spectroradiometers, currently used for solar UV measurements, show a large variation in the quality of their solar UV measurements. Most of the instruments overestimate the erythema weighted UV index - in particular at low solar zenith angles - due to stray light contribution in the UV-B range. The spectral analysis of global solar UV irradiance further supported the finding that the uncertainties in the UV-B range are very large due to stray light contribution in this wavelength range. In summary, the UV index may be detected by some commercially available array spectroradiometer within 5 % compared to the world reference spectroradiometer, if well characterized and calibrated, but only for a limited range or solar zenith angle. Generally, the tested instruments are not yet suitable for solar UV measurements for the entire range between 290 to 400 nm under all atmospheric conditions.

Solar influences on global change

NASA Technical Reports Server (NTRS)

1994-01-01

Monitoring of the Sun and the Earth has yielded new knowledge essential to this debate. There is now no doubt that the total radiative energy from the Sun that heats the Earth's surface changes over decadal time scales as a consequence of solar activity. Observations indicate as well that changes in ultraviolet radiation and energetic particles from the Sun, also connected with the solar activity, modulate the layer of ozone that protects the biosphere from the solar ultraviolet radiation. This report reassesses solar influences on global change in the light of this new knowledge of solar and atmospheric variability. Moreover, the report considers climate change to be encompassed within the broader concept of global change; thus the biosphere is recognized to be part of a larger, coupled Earth system. Implementing a program to continuously monitor solar irradiance over the next several decades will provide the opportunity to estimate solar influences on global change, assuming continued maintenance of observations of climate and other potential forcing mechanisms. In the lower atmosphere, an increase in solar radiation is expected to cause global warming. In the stratosphere, however, the two effects produce temperature changes of opposite sign. A monitoring program that would augment long term observations of tropospheric parameters with similar observations of stratospheric parameters could separate these diverse climate perturbations and perhaps isolate a greenhouse footprint of climate change. Monitoring global change in the troposphere is a key element of all facets of the United States Global Change Research Program (USGCRP), not just of the study of solar influences on global change. The need for monitoring the stratosphere is also important for global change research in its own right because of the stratospheric ozone layer.

Tissue irradiator

DOEpatents

Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

1975-12-16

A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in- vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood- carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170.

Analysis of spatial patterns underlying the linkage between solar irradiance and near-surface air temperatures

NASA Astrophysics Data System (ADS)

Balling, Robert C.; Roy, Shouraseni Sen

2005-06-01

Many scientists have noted that global temperature anomalies were highly correlated with solar irradiance values until sometime in the 1970s, but since that time, the pronounced warming in the near-surface temperature record is not explained by variations or trends in solar receipt. In this investigation, spatial dimensions are explored in the relationship between irradiance and near-surface air temperatures. At the scale of individual 5° by 5° grid cells, the solar control on annual temperature variations is not statistically significant. When the temperature data are aggregated by 5° latitudinal bands, the solar - temperature connect is generally significant, and in every band, there is substantial evidence that a non-solar control has become dominant in recent decades. The buildup of greenhouse gases and/or some other global-scale feedback, such as widespread changes in atmospheric water vapor, emerge as potential explanations for the recent residual warming found in all latitudinal bands.

Optical imaging of irradiated and non-irradiated hearts (Conference Presentation)

NASA Astrophysics Data System (ADS)

Bolin, Stephanie; Chen, Guanchu; Medhora, Meetha M.; Camara, Amadou K. S.; Ranji, Mahsa

2016-03-01

Objective: In this study, the metabolic state of the heart tissue is studied in a rodent model of ischemia and reperfusion (IR) in rats exposed to irradiation injury using a cryofluorescence imaging technique. Mitochondrial metabolic state is evaluated by autofluorescence of mitochondrial metabolic coenzymes NADH and FAD. The redox ratio (NADH/FAD) is used as a biochemical/metabolic marker of oxidative stress, before, during and after IR. Materials and methods: Hearts were extracted from non-irradiated (control) and irradiated rats (Irr) given 15 Gy whole thorax irradiation rats (WTI). After 35 days, before the onset of radiation pneumonitis, these two groups of hearts were subjected to one of three treatments; Time control (TC; hearts perfused for the duration of the protocol without ischemia or IR), 25 minutes ischemia with no reperfusion and 25 minutes ischemia followed by 60 minutes reperfusion (IR). Hearts were removed from the Langendorff perfusion system and immediately snap frozen in liquid N2 to preserve the metabolic state after injury; 3-dimensional (3D) cryo-fluorescent imager was used to obtain in fixed time NADH and FAD fluorescence images and their distribution across the entire ventricles. In this study, a 30-μm axial resolution was used resulting in 550 cross-section images per heart. The 3D images of the redox ratio and their respective histograms were calculated in the six groups of hearts. Results: We compared the mean values of the redox ratio in each group, which demonstrate a reduced mitochondrial redox state in both irradiated and non-irradiated ischemic hearts and an oxidized mitochondrial redox state for both irradiated and non-irradiated ischemia-reperfusion hearts compared to control hearts. For non-irradiated hearts, ischemia and IR injuries resulted respectively in 61% increase and 54% decrease in redox ratio when compared with TC. For irradiated hearts, ischemia and IR injuries resulted respectively in 90% increase and 50% decrease

Irradiation hardening of pure tungsten exposed to neutron irradiation

DOE PAGES

Hu, Xunxiang; Koyanagi, Takaaki; Fukuda, Makoto; ...

2016-08-26

In this paper, pure tungsten samples have been neutron irradiated in HFIR at 90–850 °C to 0.03–2.2 dpa. A dispersed barrier hardening model informed by the available microstructure data has been used to predict the hardness. Comparison of the model predictions and the measured Vickers hardness reveals the dominant hardening contribution at various irradiation conditions. For tungsten samples irradiated in HFIR, the results indicate that voids and dislocation loops contributed to the hardness increase in the low dose region (<0.3 dpa), while the formation of intermetallic second phase precipitation, resulting from transmutation, dominates the radiation-induced strengthening beginning with a relativelymore » modest dose (>0.6 dpa). Finally, the precipitate contribution is most pronounced for the HFIR irradiations, whereas the radiation-induced defect cluster microstructure can rationalize the entirety of the hardness increase observed in tungsten irradiated in the fast neutron spectrum of Joyo and the mixed neutron spectrum of JMTR.« less

Identification of periods of clear sky irradiance in time series of GHI measurements

DOE PAGES

Reno, Matthew J.; Hansen, Clifford W.

2016-01-18

In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

Identification of periods of clear sky irradiance in time series of GHI measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reno, Matthew J.; Hansen, Clifford W.

In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

PARAFAC Modeling of Irradiation- and Oxidation-Induced Changes in Fluorescent Dissolved Organic Matter Extracted from Poultry Litter.

PubMed

Mangalgiri, Kiranmayi P; Timko, Stephen A; Gonsior, Michael; Blaney, Lee

2017-07-18

Parallel factor analysis (PARAFAC) applied to fluorescence excitation emission matrices (EEMs) allows quantitative assessment of the composition of fluorescent dissolved organic matter (DOM). In this study, we fit a four-component EEM-PARAFAC model to characterize DOM extracted from poultry litter. The data set included fluorescence EEMs from 291 untreated, irradiated (253.7 nm, 310-410 nm), and oxidized (UV-H 2 O 2 , ozone) poultry litter extracts. The four components were identified as microbial humic-, terrestrial humic-, tyrosine-, and tryptophan-like fluorescent signatures. The Tucker's congruence coefficients for components from the global (i.e., aggregated sample set) model and local (i.e., single poultry litter source) models were greater than 0.99, suggesting that the global EEM-PARAFAC model may be suitable to study poultry litter DOM from individual sources. In general, the transformation trends of the four fluorescence components were comparable for all poultry litter sources tested. For irradiation at 253.7 nm, ozonation, and UV-H 2 O 2 advanced oxidation, transformation of the humic-like components was slower than that of the tryptophan-like component. The opposite trend was observed for irradiation at 310-410 nm, due to differences in UV absorbance properties of components. Compared to the other EEM-PARAFAC components, the tyrosine-like component was fairly recalcitrant in irradiation and oxidation processes. This novel application of EEM-PARAFAC modeling provides insight into the composition and fate of agricultural DOM in natural and engineered systems.

UV-B radiation amplification factor determined based on the simultaneous observation of total ozone and global spectral irradiance

NASA Technical Reports Server (NTRS)

Ito, T.; Sakoda, Y.; Matsubara, K.; Kajihara, R.; Uekubo, T.; Kobayashi, M.; Shitamichi, M.; Ueno, T.; Ito, M.

1994-01-01

The Japan Meteorological Agency started the spectral observation of solar ultraviolet (UV) irradiance on 1 January 1990 at Tateno, Aerological Observatory in Tsukuba (35 deg N, 140 deg E). The observation has been carried out using the Brewer spectrophotometer for the wavelengths from 290 to 325 nm with a 0.5 nm interval every hour from 30 minutes before sunrise to 30 minutes after sunset throughout a year. Because of remarkable similarity within observed spectra, an observed spectrum can be expressed by a simple combination of a reference spectrum and two parameters expressing the deformation of the observed spectrum from the reference. By use of the relation between one of the deformation parameters and the total ozone simultaneously observed with the Dobson spectrophotometer, the possible increase of UV irradiance due to ozone depletion is estimated. For damaging UV, the irradiance possibly increases about 19 percent with the ozone depletion of 10 percent at noon throughout the year in the northern midlatitudes. DUV at noon on the summer solstice possibly increases about 5.6 percent with the ozone depletion of 10 m atm-cm for all latitudes in the Northern Hemisphere.

Annually and monthly resolved solar irradiance and atmospheric temperature data across the Hawaiian archipelago from 1998 to 2015 with interannual summary statistics.

PubMed

Bryce, Richard; Losada Carreño, Ignacio; Kumler, Andrew; Hodge, Bri-Mathias; Roberts, Billy; Brancucci Martinez-Anido, Carlo

2018-08-01

This article contains data and summary statistics of solar irradiance and dry bulb temperature across the Hawaiian archipelago resolved on a monthly basis and spanning years 1998-2015. This data was derived in association with an article titled "Consequences of Neglecting the Interannual Variability of the Solar Resource: A Case Study of Photovoltaic Power Among the Hawaiian Islands" (Bryce et al., 2018 [7]). The solar irradiance data is presented in terms of Direct Normal Irradiance (DNI), Diffuse Horizontal Irradiance (DHI), and Global Horizontal Irradiance (GHI) and was obtained from the satellite-derived data contained in the National Solar Radiation Database (NSRDB). The temperature data is also obtained from this source. We have processed the NSRDB data and compiled these monthly resolved data sets, along with interannual summary statistics including the interannual coefficient of variability.

The influence of late-stage pupal irradiation and increased irradiated: un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton.

PubMed

Helinski, M E H; Knols, B G J

2009-06-01

Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments with a higher ratio of irradiated versus un-irradiated males were performed. Second, pupae were irradiated just prior to emergence and male mating competitiveness was determined. Males were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. Pupae were irradiated aged 20-26 h (young) as routinely performed, or the pupal stage was artificially prolonged by cooling and pupae were irradiated aged 42-48 h (old). Irradiated males competed at a ratio of 3:1:1 to un-irradiated males for mates in a large cage design. At the 3:1 ratio, the number of females inseminated by males irradiated with 70 Gy as young pupae was similar to the number inseminated by un-irradiated males for the majority of the replicates. At 120 Gy, significantly fewer females were inseminated by irradiated than by un-irradiated males. The irradiation of older pupae did not result in a significantly improved male mating competitiveness compared to the irradiation of young pupae. Our findings indicate that the loss of competitiveness after pupal stage irradiation can be compensated for by a threefold increase of irradiated males, but only for the partially-sterilizing dose. In addition, cooling might be a useful tool to facilitate handling processes of large numbers of mosquitoes in genetic control programmes.

CD47 Receptor Globally Regulates Metabolic Pathways That Control Resistance to Ionizing Radiation*

PubMed Central

Miller, Thomas W.; Soto-Pantoja, David R.; Schwartz, Anthony L.; Sipes, John M.; DeGraff, William G.; Ridnour, Lisa A.; Wink, David A.; Roberts, David D.

2015-01-01

Modulating tissue responses to stress is an important therapeutic objective. Oxidative and genotoxic stresses caused by ionizing radiation are detrimental to healthy tissues but beneficial for treatment of cancer. CD47 is a signaling receptor for thrombospondin-1 and an attractive therapeutic target because blocking CD47 signaling protects normal tissues while sensitizing tumors to ionizing radiation. Here we utilized a metabolomic approach to define molecular mechanisms underlying this radioprotective activity. CD47-deficient cells and cd47-null mice exhibited global advantages in preserving metabolite levels after irradiation. Metabolic pathways required for controlling oxidative stress and mediating DNA repair were enhanced. Some cellular energetics pathways differed basally in CD47-deficient cells, and the global declines in the glycolytic and tricarboxylic acid cycle metabolites characteristic of normal cell and tissue responses to irradiation were prevented in the absence of CD47. Thus, CD47 mediates signaling from the extracellular matrix that coordinately regulates basal metabolism and cytoprotective responses to radiation injury. PMID:26311851

Wavelength Dependence of Solar Flare Irradiation and its Influence on the Thermosphere

NASA Technical Reports Server (NTRS)

Huang, Yanshi; Richmond, Arthur D.; Deng, Yue; Qian, L.; Solomon, S.; Chamberlin, P.

2012-01-01

The wavelength dependence of solar flare enhancement is one of the important factors determining how the Thermosphere-Ionosphere (T-I) system response to flares. To investigate the wavelength dependence of solar flare, the Flare Irradiance Spectral Model (FISM) has been run for 34 X-class flares. The results show that the percentage increases of solar irradiance at flare peak comparing to pre-flare condition have a clear wavelength dependence. In the wavelength range between 0 - 195 nm, it can vary from 1% to 10000%. The solar irradiance enhancement is largest ( 1000%) in the XUV range (0 - 25 nm), and is about 100% in EUV range (25 - 120 nm). The influence of different wavebands on the T-I system during the October 28th, 2003 flare (X17.2-class) has also been examined using the latest version of National Center for Atmospheric Research (NCAR) Thermosphere- Ionosphere-Electrodynamics General Circulation Model (TIE-GCM). While the globally integrated solar energy deposition is largest in the 0 - 14 nm waveband, the impact of solar irradiance enhancement on the thermosphere at 400 km is largest for 25 - 105 nm waveband. The effect of 122 - 195 nm is small in magnitude, but it decays slowly.

Mass spectrometric evidence for the modification of small molecules in a cobalt-60-irradiated rodent diet.

PubMed

Prasain, J K; Wilson, L S; Arabshahi, A; Grubbs, C; Barnes, S

2017-08-01

The purpose of this study was to investigate the effect of radiation on the content of animal diet constituents using global metabolomics. Aqueous methanolic extracts of control and cobalt-60-irradiated Teklad 7001 diets were comprehensively analyzed using nano-liquid chromatography-MS/MS. Among the over 2000 ions revealed by XCMS followed by data preprocessing, 94 positive and 143 negative metabolite ions had greater than 1.5-fold changes and p-values <0.01. Use of MetaboAnalyst statistical software demonstrated complete separation of the irradiated and non-radiated diets in unsupervised principal components analysis and supervised partial least squares discriminant analysis. Irradiation led to an increase in the content of phytochemicals such as glucosinolates and oxidized lipids in the diet. Twenty-eight metabolites that were significantly changed in the irradiated samples were putatively identified at the level of molecular formulae by MS/MS. MS/MS ALL analysis of chloroform-methanol extracts of the irradiated diet showed increased levels of a number of unique linoleic acid-derived branched fatty acid esters of hydroxy fatty acids. These data imply that gamma irradiation of animal diets causes chemical changes to dietary components, which in turn may influence the risk of mammary cancer. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Dosimetry Formalism and Implementation of a Homogenous Irradiation Protocol to Improve the Accuracy of Small Animal Whole-Body Irradiation Using a Cesium-137 Irradiator

PubMed Central

Brodin, N. Patrik; Chen, Yong; Yaparpalvi, Ravindra; Guha, Chandan; Tomé, Wolfgang A.

2015-01-01

Shielded 137Cs irradiators are routinely used in pre-clinical radiation research to perform in vitro or in vivo investigations. Without appropriate dosimetry and irradiation protocols in place, there can be large uncertainty in the delivered dose of radiation between irradiated subjects that could lead to inaccurate and possibly misleading results. Here, a dosimetric evaluation of the JL Shepard Mark I-68A 137Cs irradiator and an irradiation technique for whole-body irradiation of small animals that allows one to limit the between subject variation in delivered dose to ±3% are provided. Mathematical simulation techniques and Gafchromic EBT film were used to describe the region within the irradiation cavity with homogeneous dose distribution (100% ±5%), the dosimetric impact of varying source-to-subject distance, and the variation in attenuation thickness due to turntable rotation. Furthermore, an irradiation protocol and dosimetry formalism that allows calculation of irradiation time for whole-body irradiation of small animals is proposed, that is designed to ensure a more consistent dose delivery between irradiated subjects. To compare this protocol with the conventional irradiation protocol suggested by the vendor, high-resolution film dosimetry measurements evaluating the dose difference between irradiation subjects and the dose distribution throughout subjects was performed, using phantoms resembling small animals. Based on these results, there can be considerable variation in the delivered dose of > ±5% using the conventional irradiation protocol for whole-body irradiation doses below 5 Gy. Using the proposed irradiation protocol this variability can be reduced to within ±3% and the dosimetry formalism allows for more accurate calculation of the irradiation time in relation to the intended prescription dose. PMID:26710162

Irradiated foods

MedlinePlus

... materials that kill bacteria. The process is called irradiation. It is used to remove germs from food. ... it reduces the risk for food poisoning . Food irradiation is used in many countries. It was first ...

Influence of synoptic weather patterns on solar irradiance variability in Europe

NASA Astrophysics Data System (ADS)

Parding, Kajsa; Hinkelman, Laura; Liepert, Beate; Ackerman, Thomas; Dagestad, Knut-Frode; Asle Olseth, Jan

2014-05-01

Solar radiation is important for many aspects of existence on Earth, including the biosphere, the hydrological cycle, and creatures living on the planet. Previous studies have reported decadal trends in observational records of surface shortwave (SW) irradiance around the world, too strong to be caused by varying solar output. These observed decadal trends have been dubbed "solar dimming and brightening" and are believed to be related to changes in atmospheric aerosols and cloud cover. Because the observed solar variability coincides with qualitative air pollution histories, the dimming and brightening have become almost synonymous with shortwave attenuation by anthropogenic aerosols. However, there are indications that atmospheric circulation patterns have influenced the dimming and brightening in some regions, e.g., Alaska and Scandinavia. In this work, we focus on the role of atmospheric circulation patterns in modifying shortwave irradiance. An examination of European SW irradiance data from the Global Energy Balance Archive (GEBA) shows that while there are periods of predominantly decreasing (~1970-1985) and increasing (~1985-2007) SW irradiance, the changes are not spatially uniform within Europe and in a majority of locations not statistically significant. To establish a connection between weather patterns and sunshine, regression models of SW irradiance are fitted using a daily classification of European weather called Grosswetterlagen (GWL). The GWL reconstructions of shortwave irradiance represent the part of the solar variability that is related to large scale weather patterns, which should be effectively separated from the influence of varying anthropogenic aerosol emissions. The correlation (R) between observed and reconstruced SW irradiance is between 0.31 and 0.75, depending on station and season, all statistically significant (p<0.05, estimated with a bootstrap test). In central and eastern parts of Europe, the observed decadal SW variability is

Combined treatment of UVA irradiation and antibiotics induces greater bactericidal effects on Vibrio parahaemolyticus.

PubMed

Hou, Yanfei; Nakahashi, Mutsumi; Mawatari, Kazuaki; Shimohata, Takaaki; Uebanso, Takashi; Harada, Yumi; Tsunedomi, Akari; Emoto, Takahiro; Akutagawa, Masatake; Kinouchi, Yohsuke; Takahashi, Akira

2016-01-01

The presence of antibiotics in the environment and their subsequent impact on the development of multi-antibiotic resistant bacteria has raised concerns globally. Consequently, much research is focused on a method to produce a better disinfectant. We have established a disinfectant system using UVA-LED that inactivates pathogenic bacteria. We assessed the bactericidal efficiency of a combination of UVA-LED and antibiotics against Vibrio parahaemolyticus. Combined use of antibiotic drugs and UVA irradiation was more bactericidal than UVA irradiation or antibacterial drugs alone. The bactericidal synergy was observed at low concentrations of each drug that are normally unable to kill the bacteria. This combination has the potential to become a sterilization technology.

Use of Irradiated Foods

NASA Technical Reports Server (NTRS)

Brynjolfsson, A.

1985-01-01

The safety of irradiated foods is reviewed. Guidelines and regulations for processing irradiated foods are considered. The radiolytic products formed in food when it is irradiated and its wholesomeness is discussed. It is concluded that food irradiation processing is not a panacea for all problems in food processing but when properly used will serve the space station well.

Insufficient cure under the condition of high irradiance and short irradiation time.

PubMed

Feng, Li; Carvalho, Ricardo; Suh, Byoung I

2009-03-01

To investigate if and why a plasma arc curing (PAC) light tends to undercure methacrylate-based resins or resin composites. Model dimethacrylate resins, commercial dental adhesives, and commercial resin composites were cured using a PAC light and a halogen light with the similar radiant exposures but different combinations of irradiance and irradiation time. The degree of double bond conversion (DC) was measured with FTIR spectroscopy and analyzed as a function of radiant exposure. The PAC light produced a lower DC than the halogen light for the model resin with the lowest viscosity and for three of the four adhesives. With a high irradiance, the PAC light could cure three of the four composites as thoroughly as its halogen counterpart. When the irradiance was reduced, however, three composites yielded a lower DC. Insufficient cure by PAC lights or any curing lights with very high irradiance is likely to happen when too short an irradiation time is used. It is because under higher irradiance, the lifetime of free radicals is shorter.

Effect of Gamma Ray Irradiation on Interlaminar Shear Strength of Glass Fiber Reinforced Plastics at 77 K

NASA Astrophysics Data System (ADS)

Nishimura, A.; Nishijima, S.; Izumi, Y.

2008-03-01

It is known that an organic material is damaged by gamma ray irradiation, and the strength after irradiation has dependence on the gamma ray dose. These issues are important not only to make global understanding of electric insulating performance of glass fiber reinforced plastics (GFRP) under irradiation condition but also to develop new insulation materials. This paper presents the dependence of fracture mode and interlaminar shear strength (ILSS) on the material and the gamma ray irradiation effect on the fracture mode and the ILSS. 6 mm radius loading nose and supports were used to prompt ILS fracture for a short beam test. A 2.5 mm thick small specimen machined out of a 13 mm thick G-10CR GFRP plate (sliced specimen) showed lower ILSS and translaminar shear (TLS) fracture, although the same size specimen prepared from a 2.5 mm G-10CR GFRP plate (non-sliced specimen) showed ILS fracture and the higher ILSS. Both type of specimens showed the degradation of ILSS after gamma ray irradiation. The fracture mode of the non-sliced specimen changed from ILS to TLS fracture and no bending fracture was observed. The resistance to shear deformation of glass cloth/epoxy laminate structure would be damaged by the irradiation.

Changes in surface solar UV irradiances and total ozone during the solar eclipse of August 11, 1999

NASA Astrophysics Data System (ADS)

Zerefos, C. S.; Balis, D. S.; Meleti, C.; Bais, A. F.; Tourpali, K.; Kourtidis, K.; Vanicek, K.; Cappellani, F.; Kaminski, U.; Colombo, T.; Stübi, R.; Manea, L.; Formenti, P.; Andreae, M. O.

2000-11-01

During the solar eclipse of August 11, 1999, intensive measurements of UV solar irradiance and total ozone were performed at a number of observatories located near the path of the Moon's shadow. At the Laboratory of Atmospheric Physics (LAP) of the Aristotle University of Thessaloniki, Greece, global and direct spectra of UV solar irradiances (285-365 nm) were recorded with a double monochromator, and erythemal irradiances were measured with broadband pyranometers. In addition, higher-frequency measurements of global and direct irradiances at six UV wavelengths were performed with a single Brewer spectrophotometer. Total ozone measurements were also performed with Dobson and Brewer spectrophotometers at Hradec Kralove (Czech Republic), Ispra (Italy), Sestola (Italy), Hohenpeissenberg (Germany), Bucharest (Romania), Arosa (Switzerland), and Thessaloniki (Greece). From the spectral UV measurements the limb darkening effect of the solar disk was tentatively quantified from differences of measured solar spectral irradiances at the peak of the eclipse (near to limb conditions) and before the eclipse. Two blackbody curves were fit to the preeclipse and peak eclipse spectra, which have shown a difference in effective temperatures of about 165°K between the limb and the whole of the solar disk. The limb darkening effect is larger at the shorter UV wavelengths. The ratio of the diffuse to direct solar irradiances during the eclipse shows that the diffuse component is reduced much less compared to the decline of the direct solar irradiance at the shorter wavelengths. Moreover, a 20-min oscillation of erythemal UV-B solar irradiance was observed before and after the time of the eclipse maximum under clear skies, indicating a possible 20-min fluctuation in total ozone, presumably caused by the eclipse-induced gravity waves. This work also shows that routine total ozone measurements with a Brewer or a Dobson spectrophotometer should be used with caution during a solar eclipse

DREAMS-SIS: The Solar Irradiance Sensor on-board the ExoMars 2016 lander

NASA Astrophysics Data System (ADS)

Arruego, I.; Apéstigue, V.; Jiménez-Martín, J.; Martínez-Oter, J.; Álvarez-Ríos, F. J.; González-Guerrero, M.; Rivas, J.; Azcue, J.; Martín, I.; Toledo, D.; Gómez, L.; Jiménez-Michavila, M.; Yela, M.

2017-07-01

The Solar Irradiance Sensor (SIS) was part of the DREAMS (Dust characterization, Risk assessment, and Environment Analyzer on the Martian Surface) payload package on board the ExoMars 2016 Entry and Descent Module (EDM), "Schiaparelli". DREAMS was a meteorological station aimed at the measurement of several atmospheric parameters, as well as the presence of electric fields, during the surface operations of EDM. DREAMS-SIS is a highly miniaturized lightweight sensor designed for small meteorological stations, capable of estimating the aerosol optical depth (AOD) several times per sol, as well as performing a direct measurement of the global (direct plus scattered) irradiance on the Martian surface in the spectral range between 200 and 1100 nm. AOD is estimated from the irradiance measurements at two different spectral bands - Ultraviolet (UV) and near infrared (NIR) - which also enables color index (CI) analysis for the detection of clouds. Despite the failure in the landing of Schiaparelli, DREAMS-SIS is a valuable precursor for new developments being carried-on at present. The concept and design of DREAMS-SIS are here presented and its operating principles, supported by preliminary results from a short validation test, are described. Lessons learnt and future work towards a new generation of Sun irradiance sensors is also outlined.

Proton irradiation of simple gas mixtures: Influence of irradiation parameters

NASA Technical Reports Server (NTRS)

Sack, Norbert J.; Schuster, R.; Hofmann, A.

1990-01-01

In order to get information about the influence of irradiation parameters on radiolysis processes of astrophysical interest, methane gas targets were irradiated with 6.5 MeV protons at a pressure of 1 bar and room temperature. Yields of higher hydrocarbons like ethane or propane were found by analysis of irradiated gas samples using gas chromatography. The handling of the proton beam was of great experimental importance for determining the irradiation parameters. In a series of experiments current density of the proton beam and total absorbed energy were shown to have a large influence on the yields of produced hydrocarbons. Mechanistic interpretations of the results are given and conclusions are drawn with regard to the chemistry and the simulation of various astrophysical systems.

Simulating PACE Global Ocean Radiances

NASA Technical Reports Server (NTRS)

Gregg, Watson W.; Rousseaux, Cecile S.

2017-01-01

The NASA PACE mission is a hyper-spectral radiometer planned for launch in the next decade. It is intended to provide new information on ocean biogeochemical constituents by parsing the details of high resolution spectral absorption and scattering. It is the first of its kind for global applications and as such, poses challenges for design and operation. To support pre-launch mission development and assess on-orbit capabilities, the NASA Global Modeling and Assimilation Office has developed a dynamic simulation of global water-leaving radiances, using an ocean model containing multiple ocean phytoplankton groups, particulate detritus, particulate inorganic carbon (PIC), and chromophoric dissolved organic carbon (CDOC) along with optical absorption and scattering processes at 1 nm spectral resolution. The purpose here is to assess the skill of the dynamic model and derived global radiances. Global bias, uncertainty, and correlation are derived using available modern satellite radiances at moderate spectral resolution. Total chlorophyll, PIC, and the absorption coefficient of CDOC (aCDOC), are simultaneously assimilated to improve the fidelity of the optical constituent fields. A 5-year simulation showed statistically significant (P < 0.05) comparisons of chlorophyll (r = 0.869), PIC (r = 0.868), and a CDOC (r =0.890) with satellite data. Additionally, diatoms (r = 0.890), cyanobacteria (r = 0.732), and coccolithophores (r = 0.716) were significantly correlated with in situ data. Global assimilated distributions of optical constituents were coupled with a radiative transfer model (Ocean-Atmosphere Spectral Irradiance Model, OASIM) to estimate normalized water-leaving radiances at 1 nm for the spectral range 250-800 nm. These unassimilated radiances were within 0.074 mW/sq cm/micron/sr of MODIS-Aqua radiances at 412, 443, 488, 531, 547, and 667 nm. This difference represented a bias of 10.4% (model low). A mean correlation of 0.706 (P < 0.05) was found with global

Simulating PACE Global Ocean Radiances

PubMed Central

Gregg, Watson W.; Rousseaux, Cécile S.

2017-01-01

The NASA PACE mission is a hyper-spectral radiometer planned for launch in the next decade. It is intended to provide new information on ocean biogeochemical constituents by parsing the details of high resolution spectral absorption and scattering. It is the first of its kind for global applications and as such, poses challenges for design and operation. To support pre-launch mission development and assess on-orbit capabilities, the NASA Global Modeling and Assimilation Office has developed a dynamic simulation of global water-leaving radiances, using an ocean model containing multiple ocean phytoplankton groups, particulate detritus, particulate inorganic carbon (PIC), and chromophoric dissolved organic carbon (CDOC) along with optical absorption and scattering processes at 1 nm spectral resolution. The purpose here is to assess the skill of the dynamic model and derived global radiances. Global bias, uncertainty, and correlation are derived using available modern satellite radiances at moderate spectral resolution. Total chlorophyll, PIC, and the absorption coefficient of CDOC (aCDOC), are simultaneously assimilated to improve the fidelity of the optical constituent fields. A 5-year simulation showed statistically significant (P <0.05) comparisons of chlorophyll (r = 0.869), PIC (r = 0.868), and aCDOC (r = 0.890) with satellite data. Additionally, diatoms (r = 0.890), cyanobacteria (r = 0.732), and coccolithophores (r = 0.716) were significantly correlated with in situ data. Global assimilated distributions of optical constituents were coupled with a radiative transfer model (Ocean-Atmosphere Spectral Irradiance Model, OASIM) to estimate normalized water-leaving radiances at 1 nm for the spectral range 250–800 nm. These unassimilated radiances were within −0.074 mW cm−2 μm1 sr−1 of MODIS-Aqua radiances at 412, 443, 488, 531, 547, and 667 nm. This difference represented a bias of −10.4% (model low). A mean correlation of 0.706 (P < 0.05) was found with

KEY RESULTS FROM IRRADIATION AND POST-IRRADIATION EXAMINATION OF AGR-1 UCO TRISO FUEL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demkowicz, Paul A.; Hunn, John D.; Petti, David A.

The AGR-1 irradiation experiment was performed as the first test of tristructural isotropic (TRISO) fuel in the US Advanced Gas Reactor Fuel Development and Qualification Program. The experiment consisted of 72 right cylinder fuel compacts containing approximately 3×105 coated fuel particles with uranium oxide/uranium carbide (UCO) fuel kernels. The fuel was irradiated in the Advanced Test Reactor for a total of 620 effective full power days. Fuel burnup ranged from 11.3 to 19.6% fissions per initial metal atom and time average, volume average irradiation temperatures of the individual compacts ranged from 955 to 1136°C. This paper focuses on key resultsmore » from the irradiation and post-irradiation examination, which revealed a robust fuel with excellent performance characteristics under the conditions tested and have significantly improved the understanding of UCO coated particle fuel irradiation behavior within the US program. The fuel exhibited a very low incidence of TRISO coating failure during irradiation and post-irradiation safety testing at temperatures up to 1800°C. Advanced PIE methods have allowed particles with SiC coating failure to be isolated and meticulously examined, which has elucidated the specific causes of SiC failure in these specimens. The level of fission product release from the fuel during irradiation and post-irradiation safety testing has been studied in detail. Results indicated very low release of krypton and cesium through intact SiC and modest release of europium and strontium, while also confirming the potential for significant silver release through the coatings depending on irradiation conditions. Focused study of fission products within the coating layers of irradiated particles down to nanometer length scales has provided new insights into fission product transport through the coating layers and the role various fission products may have on coating integrity. The broader implications of these results and the application

Rescue of CD8+ T cell vaccine memory following sublethal γ irradiation.

PubMed

McFarland, Hugh I; Berkson, Julia D; Lee, Jay P; Elkahloun, Abdel G; Mason, Karen P; Rosenberg, Amy S

2015-07-31

Sublethal γ irradiation eliminates CD8+ T cell mediated memory responses. In this work, we explored how these memory responses could be rescued in the aftermath of such exposure. We utilized two models of CD8+ T cell mediated immunity: a mouse model of Listeria monocytogenes (LM) infection in which CD8+ T cells specific for LM expressed antigens (Listeriolysin O, LLO) can be tracked, and a murine skin graft model in which CD8+ T cells mediate rejection across a MHC class I (D(d)) disparity. In the LM immunized mice, LL0 specific CD8+ T memory cells were lost on irradiation, preserved with rapid revaccination with an attenuated strain 1-3 days post-irradiation (PI), and these mice survived a subsequent wild type LM challenge. A genetic "signature of rescue" identified a group of immune-associated mRNA maintained or upregulated following irradiation and rescue. A number of these factors, including IL-36γ, dectin-2 (Clec4n), and mir101c are upregulated rapidly after exposure of mice to sublethal γ radiation alone and are sustained by early, but not later rescue. Such factors will be evaluated as potential therapeutics to replace individual vaccines for global rescue of CD8+ T memory cell responses following sublethal γ irradiation. The skin allograft model mirrored that of the LM model in that the accelerated D(d) skin allograft rejection response was lost in mice exposed to sublethal γ radiation, but infusion of allogeneic D(d) expressing bone marrow cells 1-4 days PI preserved the CD8+ T memory mediated accelerated rejection response, further suggesting that innate immune responses may not always be essential to rescue of CD8+ memory T cells following γ irradiation. Published by Elsevier Ltd.

Global map of solar power production efficiency, considering micro climate factors

NASA Astrophysics Data System (ADS)

Hassanpour Adeh, E.; Higgins, C. W.

2017-12-01

Natural resources degradation and greenhouse gas emissions are creating a global crisis. Renewable energy is the most reliable option to mitigate this environmental dilemma. Abundancy of solar energy makes it highly attractive source of electricity. The existing global spatial maps of available solar energy are created with various models which consider the irradiation, latitude, cloud cover, elevation, shading and aerosols, and neglect the influence of local meteorological conditions. In this research, the influences of microclimatological variables on solar energy productivity were investigated with an in-field study at the Rabbit Hills solar arrays near Oregon State University. The local studies were extended to a global level, where global maps of solar power were produced, taking the micro climate variables into account. These variables included: temperature, relative humidity, wind speed, wind direction, solar radiation. The energy balance approach was used to synthesize the data and compute the efficiencies. The results confirmed that the solar power efficiency can be directly affected by the air temperature and wind speed.

Grafting of styrene into pre-irradiated fluoropolymer films: Influence of base material and irradiation temperature

NASA Astrophysics Data System (ADS)

Lappan, Uwe; Geißler, Uwe; Gohs, Uwe; Uhlmann, Steffi

2010-10-01

In this study, the influence of irradiation temperature on mechanical properties of three fluoropolymers and on grafting of styrene into the polymers by the pre-irradiation method was investigated. Electron paramagnetic resonance spectroscopy and infrared spectroscopy were used to characterize the irradiated polymers regarding trapped radical species and changes in the chemical structure, respectively. For poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) the irradiation temperature was found to be an important factor for tensile strength and elongation at break of the pre-irradiated film. No strong effect of irradiation temperature on the mechanical properties was noticed for poly(tetrafluoroethylene-co-ethylene) (ETFE); however the yield of grafting drops at high irradiation temperatures. Finally, mechanical properties of poly(tetrafluoroethylene) (PTFE) were found to be dramatically altered, even if the film was irradiated at elevated temperature.

The Measurement of the Solar Spectral Irradiance Variability at 782 nm during the Solar Cycle 24 using the SES on-board PICARD

NASA Astrophysics Data System (ADS)

Meftah, Mustapha; Hauchecorne, Alain; Irbah, Abdanour; Bekki, Slimane

2016-04-01

A Sun Ecartometry Sensor (SES) was developed to provide the stringent pointing requirements of the PICARD satellite. The SES sensor produced an image of the Sun at 782+/-5 nm. From the SES data, we obtained a new time series of the solar spectral irradiance at 782nm from 2010 to 2014. SES observations provided a qualitatively consistent evolution of the solar spectral irradiance variability at 782 nm during the solar cycle 24. Comparisons will be made with Spectral And Total Irradiance REconstruction for the Satellite era (SATIRE-S) semi-empirical model and with the Spectral Irradiance Monitor instrument (SIM) on-board the Solar Radiation and Climate Experiment satellite (SORCE). These data will help to improve the representation of the solar forcing in the IPSL Global Circulation Model.

Optical metabolic imaging of irradiated rat heart exposed to ischemia-reperfusion injury

NASA Astrophysics Data System (ADS)

la Cour, Mette Funding; Mehrvar, Shima; Heisner, James S.; Motlagh, Mohammad Masoudi; Medhora, Meetha; Ranji, Mahsa; Camara, Amadou K. S.

2018-01-01

Whole thoracic irradiation (WTI) is known to cause deterioration in cardiac function. Whether irradiation predisposes the heart to further ischemia and reperfusion (IR) injury is not well known. The aim of this study is to examine the susceptibility of rat hearts to IR injury following a single fraction of 15 Gy WTI and to investigate the role of mitochondrial metabolism in the differential susceptibility to IR injury. After day 35 of irradiation, ex vivo hearts from irradiated and nonirradiated rats (controls) were exposed to 25-min global ischemia followed by 60-min IR, or hearts were perfused without IR for the same protocol duration [time controls (TC)]. Online fluorometry of metabolic indices [redox state: reduced nicotinamide adenine dinucleotide (NADH), oxidized flavin adenine dinucleotide (FAD), and NADH/FAD redox ratio] and functional variables [systolic left ventricular pressure (LVP), diastolic LVP (diaLVP), coronary flow (CF), and heart rate were recorded in the beating heart; developed LVP (dLVP) and rate pressure product (RPP)] were derived. At the end of each experimental protocol, hearts were immediately snap frozen in liquid N2 for later three-dimensional imaging of the mitochondrial redox state using optical cryoimaging. Irradiation caused a delay in recovery of dLVP and RPP after IR when compared to nonirradiated hearts but recovered to the same level at the end of reperfusion. CF in the irradiated hearts recovered better than the control hearts after IR injury. Both fluorometry and 3-D cryoimaging showed that in WTI and control hearts, the redox ratio increased during ischemia (reduced) and decreased on reperfusion (oxidized) when compared to their respective TCs; however, there was no significant difference in the redox state between WTI and controls. In conclusion, our results show that although irradiation of rat hearts compromised baseline cardiovascular function, it did not alter cardiac mitochondrial redox state and induce greater

Irradiation of meat products, chicken and use of irradiated spices for sausages

NASA Astrophysics Data System (ADS)

Kiss, I. F.; Beczner, J.; Zachariev, Gy.; Kovács, S.

The shelf-life of packed minced meat has been increased at least threefold at 4°C by applying a 2 kGy dose. Results have been confirmed by detailed quatitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated samples. The optimal average dose was 4 kGy for packed-frosen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterbacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the irradiated samples. In sensory evaluations there was no significant difference between untreated and irradiated samples. In 1984-1985 5100 kg irradiated chickens were marketed labelled as radiation treated. Irradiated spices (5 kGy) were used in the production of sausages (heat-treated and non-heat-treated) under industrial conditions. The microbiological contamination of irradiated spices was lower than that of ethylene oxide treated ones. The cell count in products made with irradiated spices was lower than in those made with unirradiated spices. The sausages proved to be of very good quality. In accordance with the permission, products were marketed and because of the low ratio of spices there was no need to declare them as using irradiated spices.

Anti-inflammatory effect of 635 nm irradiations on in vitro direct/indirect irradiation model.

PubMed

Lim, WonBong; Choi, Hongran; Kim, Jisun; Kim, Sangwoo; Jeon, SangMi; Zheng, Hui; Kim, DoMan; Ko, Youngjong; Kim, Donghwi; Sohn, HongMoon; Kim, OkJoon

2015-02-01

Low-level laser therapy (LLLT) has been promoted for its beneficial effects on tissue healing and pain relief. As during laser treatment it is possible to irradiate only a small area of the surface body or wound and, correspondingly, of a very small volume of the circulating blood, it is necessary to explain how its photomodification can lead to a wide spectrum of therapeutic effects. To establish the experimental model for indirect irradiation, irradiation with 635 nm was performed on immortalized human gingival fibroblasts (IGFs) in the presence of Porphyromonas gingivalis lipopolysaccharides (LPS). The irradiated medium was transferred to non-irradiated IGFs which were compared with direct irradiated IGFs. The protein expressions were assessed by Western blot, and prostaglandin E2 (PGE2 ) was measured using an enzyme-linked immunoassay. Reactive oxygen species (ROS) were measured by DCF-DA; cytokine profiles were assessed using a human inflammation antibody array. Cyclooxygenase-2 (COX-2) protein expression and PGE2 production were significantly increased in the LPS-treated group and decreased in both direct and indirect irradiated IGFs. Unlike direct irradiated IGFs, ROS level in indirect irradiated IGFs was decreased by time-dependent manners. There were significant differences of released granulocyte colony-stimulating factor (G-CSF), regulated on activated normal T-cell expressed and secreted (RANTES), and I-TAC level observed compared with direct and indirect irradiated IGFs. In addition, in the indirect irradiation group, phosphorylations of C-Raf and Erk1/2 increased significantly compared with the direct irradiation group. Thus, we suggest that not only direct exposure with 635 nm light, but also indirect exposure with 635 nm light can inhibit activation of pro-inflammatory mediators and may be clinically useful as an anti-inflammatory tool. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Food irradiation in the United States: irradiation as a phytosanitary treatment for fresh fruits and vegetables and for the control of microorganisms in meat and poultry

NASA Astrophysics Data System (ADS)

Ross, Ralph T.; Engeljohn, Dan

2000-03-01

Recently there has been a renewed focus on food irradiation in the United States (US) for the disinfestation of fresh fruits and vegetables to eliminate pests from imported agricultural commodities that could threaten the economic viability of American agriculture and for the control of bacterium E. coli 0157:H7 in beef, a pathogen that threatens the safety of the US domestic food supply. In January 1999 USDA/APHIS published in the Federal Register a rule which authorized irradiation as a guarantee treatment for papayas for movement from Hawaii to the US mainland. This treatment was never used for a number of reasons. However, in December, 1993, the US Environmental Protection Agency (EPA) published its final rule to terminate production and consumption of methyl bromide, the only remaining broad spectrum fumigant for disinfesting agricultural commodities for pests of quarantine significance on imported and exported commodities. With increased global trade pressures and the possible loss of methyl bromide as a fumigant for regulatory pests treatment made it imperative that practical treatment options be explored including irradiation. In May 1996, USDA/APHIS published a Notice of Policy which sets forth a policy statement that share positions and policies of USDA concerning the use of irradiation as a phytosanitary treatment. Subsequently in July, 1997, USDA/APHIS amended its Hawaiian regulation by increasing the dose required for papayas intended for interstate movement and by allowing carambolas and litchis also to move interstate as well. Fruits from Hawaii to the US mainland are currently being irradiated and distributed in commerce throughout the US Irradiation treatments now afford movement of many exotic fruits to the US mainland that could not be done earlier due to the lack of available treatment methods. To help combat this potential public health problem, the US Food and Drug Administration (FDA) approved treating red meat products. This process has been

Key results from irradiation and post-irradiation examination of AGR-1 UCO TRISO fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demkowicz, Paul A.; Hunn, John D.; Petti, David A.

The AGR-1 irradiation experiment was performed as the first test of tristructural isotropic (TRISO) fuel in the US Advanced Gas Reactor Fuel Development and Qualification Program. The experiment consisted of 72 right cylinder fuel compacts containing approximately 3 × 105 coated fuel particles with uranium oxide/uranium carbide (UCO) fuel kernels. The fuel was irradiated in the Advanced Test Reactor for a total of 620 effective full power days. Fuel burnup ranged from 11.3 to 19.6% fissions per initial metal atom and time-average, volume-average irradiation temperatures of the individual compacts ranged from 955 to 1136 °C. This paper focuses on keymore » results from the irradiation and post-irradiation examination, which revealed a robust fuel with excellent performance characteristics under the conditions tested and have significantly improved the understanding of UCO coated particle fuel irradiation behavior. The fuel exhibited zero TRISO coating failures (failure of all three dense coating layers) during irradiation and post-irradiation safety testing at temperatures up to 1700 °C. Advanced PIE methods have allowed particles with SiC coating failure that were discovered to be present in a very-low population to be isolated and meticulously examined, which has elucidated the specific causes of SiC failure in these specimens. The level of fission product release from the fuel during irradiation and post-irradiation safety testing has been studied in detail. Results indicated very low release of krypton and cesium through intact SiC and modest release of europium and strontium, while also confirming the potential for significant silver release through the coatings depending on irradiation conditions. Focused study of fission products within the coating layers of irradiated particles down to nanometer length scales has provided new insights into fission product transport through the coating layers and the role various fission products may have on coating

Key results from irradiation and post-irradiation examination of AGR-1 UCO TRISO fuel

DOE PAGES

Demkowicz, Paul A.; Hunn, John D.; Petti, David A.; ...

2017-09-10

The AGR-1 irradiation experiment was performed as the first test of tristructural isotropic (TRISO) fuel in the US Advanced Gas Reactor Fuel Development and Qualification Program. The experiment consisted of 72 right cylinder fuel compacts containing approximately 3 × 105 coated fuel particles with uranium oxide/uranium carbide (UCO) fuel kernels. The fuel was irradiated in the Advanced Test Reactor for a total of 620 effective full power days. Fuel burnup ranged from 11.3 to 19.6% fissions per initial metal atom and time-average, volume-average irradiation temperatures of the individual compacts ranged from 955 to 1136 °C. This paper focuses on keymore » results from the irradiation and post-irradiation examination, which revealed a robust fuel with excellent performance characteristics under the conditions tested and have significantly improved the understanding of UCO coated particle fuel irradiation behavior. The fuel exhibited zero TRISO coating failures (failure of all three dense coating layers) during irradiation and post-irradiation safety testing at temperatures up to 1700 °C. Advanced PIE methods have allowed particles with SiC coating failure that were discovered to be present in a very-low population to be isolated and meticulously examined, which has elucidated the specific causes of SiC failure in these specimens. The level of fission product release from the fuel during irradiation and post-irradiation safety testing has been studied in detail. Results indicated very low release of krypton and cesium through intact SiC and modest release of europium and strontium, while also confirming the potential for significant silver release through the coatings depending on irradiation conditions. Focused study of fission products within the coating layers of irradiated particles down to nanometer length scales has provided new insights into fission product transport through the coating layers and the role various fission products may have on coating

Craniospinal Irradiation for Trilateral Retinoblastoma Following Ocular Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marks, Lawrence B.; Bentel, Gunilla; Sherouse, George W.

A case study is presented. Craniospinal radiotherapy and a three-field pineal boost for trilateral retinoblastoma were delivered to a patient previously irradiated for ocular retinoblastoma. The availability of CT-based three-dimensional treatment planning provided the capability of identifying the previously irradiated volume as a three-dimensional anatomic structure and of designing a highly customized set of treatment beams that minimized reirradiation of that volume.

Ion irradiation to simulate neutron irradiation in model graphites: Consequences for nuclear graphite

NASA Astrophysics Data System (ADS)

Galy, N.; Toulhoat, N.; Moncoffre, N.; Pipon, Y.; Bérerd, N.; Ammar, M. R.; Simon, P.; Deldicque, D.; Sainsot, P.

2017-10-01

Due to its excellent moderator and reflector qualities, graphite was used in CO2-cooled nuclear reactors such as UNGG (Uranium Naturel-Graphite-Gaz). Neutron irradiation of graphite resulted in the production of 14C which is a key issue radionuclide for the management of the irradiated graphite waste. In order to elucidate the impact of neutron irradiation on 14C behavior, we carried out a systematic investigation of irradiation and its synergistic effects with temperature in Highly Oriented Pyrolitic Graphite (HOPG) model graphite used to simulate the coke grains of nuclear graphite. We used 13C implantation in order to simulate 14C displaced from its original structural site through recoil. The collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic damage. However, a part of the recoil carbon atom energy is also transferred to the graphite lattice through electronic excitation. The effects of the different irradiation regimes in synergy with temperature were simulated using ion irradiation by varying Sn(nuclear)/Se(electronic) stopping power. Thus, the samples were irradiated with different ions of different energies. The structure modifications were followed by High Resolution Transmission Electron Microscopy (HRTEM) and Raman microspectrometry. The results show that temperature generally counteracts the disordering effects of irradiation but the achieved reordering level strongly depends on the initial structural state of the graphite matrix. Thus, extrapolating to reactor conditions, for an initially highly disordered structure, irradiation at reactor temperatures (200 - 500 °C) should induce almost no change of the initial structure. On the contrary, when the structure is initially less disordered, there should be a "zoning" of the reordering: In "cold" high flux irradiated zones where the ballistic damage is important, the structure should be poorly reordered; In "hot" low flux irradiated zones where the ballistic

Low Doses of Gamma-Irradiation Induce an Early Bystander Effect in Zebrafish Cells Which Is Sufficient to Radioprotect Cells

PubMed Central

Pereira, Sandrine; Malard, Véronique; Ravanat, Jean-Luc; Davin, Anne-Hélène; Armengaud, Jean; Foray, Nicolas; Adam-Guillermin, Christelle

2014-01-01

The term “bystander effect” is used to describe an effect in which cells that have not been exposed to radiation are affected by irradiated cells though various intracellular signaling mechanisms. In this study we analyzed the kinetics and mechanisms of bystander effect and radioadaptation in embryonic zebrafish cells (ZF4) exposed to chronic low dose of gamma rays. ZF4 cells were irradiated for 4 hours with total doses of gamma irradiation ranging from 0.01–0.1 Gy. In two experimental conditions, the transfer of irradiated cells or culture medium from irradiated cells results in the occurrence of DNA double strand breaks in non-irradiated cells (assessed by the number of γ-H2AX foci) that are repaired at 24 hours post-irradiation whatever the dose. At low total irradiation doses the bystander effect observed does not affect DNA repair mechanisms in targeted and bystander cells. An increase in global methylation of ZF4 cells was observed in irradiated cells and bystander cells compared to control cells. We observed that pre-irradiated cells which are then irradiated for a second time with the same doses contained significantly less γ-H2AX foci than in 24 h gamma-irradiated control cells. We also showed that bystander cells that have been in contact with the pre-irradiated cells and then irradiated alone present less γ-H2AX foci compared to the control cells. This radioadaptation effect is significantly more pronounced at the highest doses. To determine the factors involved in the early events of the bystander effect, we performed an extensive comparative proteomic study of the ZF4 secretomes upon irradiation. In the experimental conditions assayed here, we showed that the early events of bystander effect are probably not due to the secretion of specific proteins neither the oxidation of these secreted proteins. These results suggest that early bystander effect may be due probably to a combination of multiple factors. PMID:24667817

MD simulation of plastic deformation nucleation in stressed crystallites under irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korchuganov, A. V., E-mail: avkor@ispms.tsc.ru; Zolnikov, K. P., E-mail: kost@ispms.tsc.ru; Kryzhevich, D. S., E-mail: kryzhev@ispms.tsc.ru

2016-12-15

The investigation of plastic deformation nucleation in metals and alloys under irradiation and mechanical loading is one of the topical issues of materials science. Specific features of nucleation and evolution of the defect system in stressed and irradiated iron, vanadium, and copper crystallites were studied by molecular dynamics simulation. Mechanical loading was performed in such a way that the modeled crystallite volume remained unchanged. The energy of the primary knock-on atom initiating a cascade of atomic displacements in a stressed crystallite was varied from 0.05 to 50 keV. It was found that atomic displacement cascades might cause global structural transformationsmore » in a region far larger than the radiation-damaged area. These changes are similar to the ones occurring in the process of mechanical loading of samples. They are implemented by twinning (in iron and vanadium) or through the formation of partial dislocation loops (in copper).« less

Detection of low amount of irradiated ingredients in non-irradiated precooked meals

NASA Astrophysics Data System (ADS)

Marchioni, Eric; Horvatovich, Peter; Ndiaye, Bara; Miesch, Michel; Hasselmann, Claude

2002-03-01

The application of the European Standards for the detection of irradiated food by thermoluminescence of silicates, electron-spin resonance spectroscopy of bones or gas chromatography-mass spectrometry of 2-alkylcyclobutanones does not allow the detection of irradiated ingredients included in small quantity in the matrix of a food which has not been irradiated, but which could be subjected to various processing technologies such as cooking, freezing or storage. The use of an enzymatic food hydrolysis carried out at moderated temperature, for the extraction of the food-contaminating silicate minerals and bone fragments, followed by a purification of the extracts by a high-density aqueous solution of sodium polytungstate, allows a simultaneous detection of weak inclusions (0.1% m:m) of irradiated spices and mechanically deboned turkey meat (MRM) included in various precooked foods. Moreover, the use of a supercritical fluid extraction procedure for the 2-alkylcyclobutanones or an additional purification step of the lipid extracts made it possible to lower the detection limit of the 2-alkylcyclobutanones radiation-induced from triglycerides. Using gas chromatography-mass spectrometry, down to 0.5% (m:m) of irradiated MRM included in non-irradiated chicken quenelles could be detected.

Sensitivity of erythemal UV/global irradiance ratios to atmospheric parameters: application for estimating erythemal radiation at four sites in Thailand

NASA Astrophysics Data System (ADS)

Buntoung, Sumaman; Janjai, Serm; Nunez, Manuel; Choosri, Pranomkorn; Pratummasoot, Noppamas; Chiwpreecha, Kulanist

2014-11-01

Factors affecting the ratio of erythemal UV (UVER) to broadband (G) irradiance were investigated in this study. Data from four solar monitoring sites in Thailand, namely Chiang Mai, Ubon Ratchathani, Nakhon Pathom and Songkhla were used to investigate the UVER/G ratio in response to geometric and atmospheric parameters. These comprised solar zenith angle, aerosol load, total ozone column, precipitable water and clearness index. A modeling scheme was developed to isolate and examine the effect of each individual environmental parameter on the ratio. Results showed that all parameters with the exception of solar zenith angle and clearness index influenced the ratios in a linear manner. These results were also used to develop a semi-empirical model for estimating hourly erythemal UV irradiance. Data from 2009 to 2010 were used to construct the ratio model while validation was performed using erythemal UV irradiance at the above four sites in 2011. The validation results showed reasonable agreement with a root mean square difference of 13.5% and mean bias difference of - 0.5%, under all sky conditions and 10.9% and - 0.3%, respectively, under cloudless conditions.

Reconstruction of erythemal UV irradiance at Hohenpeissenberg (1968-2001) considering trends of total ozone, cloudiness, and turbidity

NASA Astrophysics Data System (ADS)

Trepte, S.; Winkler, P.

2003-04-01

The global mean total column ozone amount for the period 1997-2001 was approximately 3% below the 1964-1980 average. The largest ozone decreases in the northern hemisphere midlatitudes are observed during winter-spring (˜4%), with summer-autumn decreases approximately half as large. Total ozone measured at Hohenpeissenberg, Germany (48^oN, 11^oE) shows a strong decrease by about 10% since 1968, representing the long-term downward trend over Central Europe. The main consequence of this phenomenon is the expected increase of solar ultraviolet irradiation (UV-B) reaching the Earth's surface with the known harmful effects on the biosphere. Global data records of reliable routine observations of UV irradiance are still too short for accurate estimation of long-term UV variations and trends. While direct UV mesaurements at Hohenpeissenberg are available only since 1990, the long-term development of UV-B have to be reconstructed. Besides on the amount of total ozone the UV irradiation at the ground depends also on atmospheric turbidity and cloudiness. The reconstruction method is based on statistical correlations of measured UV-B data with the influencing parameters total ozone, turbidity and cloud modification factors derived from eye-observations in connection with total solar irradiance data. These observed data allow a realistic reconstruction of the UV-B time series, since no assumption on these influencing data have to be made. A model is presented, using hourly observed spectral UV-B irradiance (1990-1998), total solar irradiance, total ozone amount (daily mean) and clouds to derive erythemal UV irradiance and daily doses at Hohenpeissenberg in the period 1968-2001. A comparison with recorded UV data shows good agreement. Due to long-term total ozone loss, peak values of erythemal UV irradiance in spring and summer at clear-sky conditions have strongly increased (+4.2%/decade in June). Mean daily doses have also increased in this season (+5.4%/decade in May) but

Microstructure evolution during helium irradiation and post-irradiation annealing in a nanostructured reduced activation steel

NASA Astrophysics Data System (ADS)

Liu, W. B.; Ji, Y. Z.; Tan, P. K.; Zhang, C.; He, C. H.; Yang, Z. G.

2016-10-01

Severe plastic deformation, intense single-beam He-ion irradiation and post-irradiation annealing were performed on a nanostructured reduced activation ferritic/martensitic (RAFM) steel to investigate the effect of grain boundaries (GBs) on its microstructure evolution during these processes. A surface layer with a depth-dependent nanocrystalline (NC) microstructure was prepared in the RAFM steel using surface mechanical attrition treatment (SMAT). Microstructure evolution after helium (He) irradiation (24.8 dpa) at room temperature and after post-irradiation annealing was investigated using Transmission Electron Microscopy (TEM). Experimental observation shows that GBs play an important role during both the irradiation and the post-irradiation annealing process. He bubbles are preferentially trapped at GBs/interfaces during irradiation and cavities with large sizes are also preferentially trapped at GBs/interfaces during post-irradiation annealing, but void denuded zones (VDZs) near GBs could not be unambiguously observed. Compared with cavities at GBs and within larger grains, cavities with smaller size and higher density are found in smaller grains. The average size of cavities increases rapidly with the increase of time during post-irradiation annealing at 823 K. Cavities with a large size are observed just after annealing for 5 min, although many of the cavities with small sizes also exist after annealing for 240 min. The potential mechanism of cavity growth behavior during post-irradiation annealing is also discussed.

A novel procedure for generating solar irradiance TSYs

NASA Astrophysics Data System (ADS)

Fanego, Vicente Lara; Rubio, Jesús Pulgar; Peruchena, Carlos M. Fernández; Romeo, Martín Gastón; Tejera, Sara Moreno; Santigosa, Lourdes Ramírez; Balderrama, Rita X. Valenzuela; Tirado, Luis F. Zarzalejo; Pantaleón, Diego Bermejo; Pérez, Manuel Silva; Contreras, Manuel Pavón; García, Ana Bernardos; Anarte, Sergio Macías

2017-06-01

Typical Solar Years (TSYs) are key parameters for the solar energy industry. In particular, TSYs are mainly used for the design and bankability analysis of solar projects. In essence, a TSY intends to describe the expected long-term behavior of the solar resource (direct and/or global irradiance) into a condensed period of one year at the specific location of interest. A TSY differs from a conventional Typical Meteorological Year (TMY) by its absence of meteorological variables other than solar radiation. Concerning the probability of exceedance (Pe) needed for bankability, various scenarios are commonly used, with Pe90, Pe95 or even Pe99 being most usually required as unfavorable scenarios, along with the most widely used median scenario (Pe50). There is no consensus in the scientific community regarding the methodology for generating TSYs for any Pe scenario. Furthermore, the application of two different construction methods to the same original dataset could produce differing TSYs. Within this framework, a group of experts has been established by the Spanish Association for Standardization and Certification (AENOR) in order to propose a method that can be standardized. The method developed by this working group, referred to as the EVA method, is presented in this contribution. Its evaluation shows that it provides reasonable results for the two main irradiance components (direct and global), with low errors in the annual estimations for any given Pe. The EVA method also preserves the long-term statistics when the computed TSYs for a specific Pe are expanded from the monthly basis used in the generation of the TSY to higher time resolutions, such as 1 hour, which are necessary for the precise energy simulation of solar systems.

Distribution and Validation of CERES Irradiance Global Data Products Via Web Based Tools

NASA Technical Reports Server (NTRS)

Rutan, David; Mitrescu, Cristian; Doelling, David; Kato, Seiji

2016-01-01

The CERES SYN1deg product provides climate quality 3-hourly globally gridded and temporally complete maps of top of atmosphere, in atmosphere, and surface fluxes. This product requires efficient release to the public and validation to maintain quality assurance. The CERES team developed web-tools for the distribution of both the global gridded products and grid boxes that contain long term validation sites that maintain high quality flux observations at the Earth's surface. These are found at: http://ceres.larc.nasa.gov/order_data.php. In this poster we explore the various tools available to users to sub-set, download, and validate using surface observations the SYN1Deg and Surface-EBAF products. We also analyze differences found in long-term records from well-maintained land surface sites such as the ARM central facility and high quality buoy radiometers, which due to their isolated nature cannot be maintained in a similar manner to their land based counterparts.

Consumer acceptance of irradiated poultry.

PubMed

Hashim, I B; Resurreccion, A V; McWatters, K H

1995-08-01

A simulated supermarket setting (SSS) test was conducted to determine whether consumers (n = 126) would purchase irradiated poultry products, and the effects of marketing strategies on consumer purchase of irradiated poultry products. Consumer preference for irradiated poultry was likewise determined using a home-use test. A slide program was the most effective educational strategy in changing consumers' purchase behavior. The number of participants who purchased irradiated boneless, skinless breasts and irradiated thighs after the educational program increased significantly from 59.5 and 61.9% to 83.3 and 85.7% for the breasts and thighs, respectively. Using a label or poster did not increase the number of participants who bought irradiated poultry products. About 84% of the participants consider it either "somewhat necessary" or "very necessary" to irradiate raw chicken and would like all chicken that was served in restaurants or fast food places to be irradiated. Fifty-eight percent of the participants would always buy irradiated chicken if available, and an additional 27% would buy it sometimes. About 44% of the participants were willing to pay the same price for irradiated chicken as for nonirradiated. About 42% of participants were willing to pay 5% or more than what they were currently paying for nonirradiated chicken. Seventy-three percent or more of consumers who participated in the home-use test (n = 74) gave the color, appearance, and aroma of the raw poultry products a minimum rating of 7 (= like moderately). After consumers participated in a home-use test, 84 and 88% selected irradiated thighs and breasts, respectively, over nonirradiated in a second SSS test.

TUNABLE IRRADIATION TESTBED

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wootan, David W.; Casella, Andrew M.; Asner, David M.

PNNL has developed and continues to develop innovative methods for characterizing irradiated materials from nuclear reactors and particle accelerators for various clients and collaborators around the world. The continued development of these methods, in addition to the ability to perform unique scientific investigations of the effects of radiation on materials could be greatly enhanced with easy access to irradiation facilities. A Tunable Irradiation Testbed with customized targets (a 30 MeV, 1mA cyclotron or similar coupled to a unique target system) is shown to provide a much more flexible and cost-effective source of irradiating particles than a test reactor or isotopicmore » source. The configuration investigated was a single shielded building with multiple beam lines from a small, flexible, high flux irradiation source. Potential applications investigated were the characterization of radiation damage to materials applicable to advanced reactors, fusion reactor, legacy waste, (via neutron spectra tailored to HTGR, molten salt, LWR, LMR, fusion environments); 252Cf replacement; characterization of radiation damage to materials of interest to High Energy Physics to enable the neutrino program; and research into production of short lived isotopes for potential medical and other applications.« less

Estimation of atmospheric turbidity and surface radiative parameters using broadband clear sky solar irradiance models in Rio de Janeiro-Brasil

NASA Astrophysics Data System (ADS)

Flores, José L.; Karam, Hugo A.; Marques Filho, Edson P.; Pereira Filho, Augusto J.

2016-02-01

The main goal of this paper is to estimate a set of optimal seasonal, daily, and hourly values of atmospheric turbidity and surface radiative parameters Ångström's turbidity coefficient ( β), Ångström's wavelength exponent ( α), aerosol single scattering albedo ( ω o ), forward scatterance ( F c ) and average surface albedo ( ρ g ), using the Brute Force multidimensional minimization method to minimize the difference between measured and simulated solar irradiance components, expressed as cost functions. In order to simulate the components of short-wave solar irradiance (direct, diffuse and global) for clear sky conditions, incidents on a horizontal surface in the Metropolitan Area of Rio de Janeiro (MARJ), Brazil (22° 51' 27″ S, 43° 13' 58″ W), we use two parameterized broadband solar irradiance models, called CPCR2 and Iqbal C, based on synoptic information. The meteorological variables such as precipitable water ( u w ) and ozone concentration ( u o ) required by the broadband solar models were obtained from moderate-resolution imaging spectroradiometer (MODIS) sensor on Terra and Aqua NASA platforms. For the implementation and validation processes, we use global and diffuse solar irradiance data measured by the radiometric platform of LabMiM, located in the north area of the MARJ. The data were measured between the years 2010 and 2012 at 1-min intervals. The performance of solar irradiance models using optimal parameters was evaluated with several quantitative statistical indicators and a subset of measured solar irradiance data. Some daily results for Ångström's wavelength exponent α were compared with Ångström's parameter (440-870 nm) values obtained by aerosol robotic network (AERONET) for 11 days, showing an acceptable level of agreement. Results for Ångström's turbidity coefficient β, associated with the amount of aerosols in the atmosphere, show a seasonal pattern according with increased precipitation during summer months (December

A Change in the Solar He II EUV Global Network Structure as an Indicator of the Geo-Effectiveness of Solar Minima

NASA Technical Reports Server (NTRS)

Didkovsky, L.; Gurman, J. B.

2013-01-01

Solar activity during 2007 - 2009 was very low, causing anomalously low thermospheric density. A comparison of solar extreme ultraviolet (EUV) irradiance in the He II spectral band (26 to 34 nm) from the Solar Extreme ultraviolet Monitor (SEM), one of instruments on the Charge Element and Isotope Analysis System (CELIAS) on board the Solar and Heliospheric Observatory (SOHO) for the two latest solar minima showed a decrease of the absolute irradiance of about 15 +/- 6 % during the solar minimum between Cycles 23 and 24 compared with the Cycle 22/23 minimum when a yearly running-mean filter was used. We found that some local, shorter-term minima including those with the same absolute EUV flux in the SEM spectral band show a higher concentration of spatial power in the global network structure from the 30.4 nm SOHO/Extreme ultraviolet Imaging Telescope (EIT) images for the local minimum of 1996 compared with the minima of 2008 - 2011.We interpret this higher concentration of spatial power in the transition region's global network structure as a larger number of larger-area features on the solar disk. These changes in the global network structure during solar minima may characterize, in part, the geo-effectiveness of the solar He II EUV irradiance in addition to the estimations based on its absolute levels.

Proposal and Evaluation of Subordinate Standard Solar Irradiance Spectra: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Habte, Aron M; Wilbert, Stefan; Jessen, Wilko

This paper introduces a concept for global tilted irradiance (GTI) subordinate standard spectra to supplement the current standard spectra used in solar photovoltaic applications as defined in ASTM G173 and IEC60904. The proposed subordinate standard spectra correspond to atmospheric conditions and tilt angles that depart significantly from the main standard spectrum, and they can be used to more accurately represent various local conditions. For the definition of subordinate standard spectra cases with an elevation 1.5 km above sea level, the question arises whether the air mass should be calculated including a pressure correction or not. This study focuses on themore » impact of air mass used in standard spectra, and it uses data from 29 locations to examine which air mass is most appropriate for GTI and direct normal irradiance (DNI) spectra. Overall, it is found that the pressure-corrected air mass of 1.5 is most appropriate for DNI spectra. For GTI, a non-pressure-corrected air mass of 1.5 was found to be more appropriate.« less

Spatial interpolation of solar irradiation data over complex orography: Solar map of Canaries Islands

NASA Astrophysics Data System (ADS)

Ortegón Gallego, A.

2010-09-01

In this paper, we describe the calculation methodology we used to determine the spatial structure of solar irradiation over a very complex orography, such as the Canary archipelago, that is broken in seven islands, with only 7500 km2, and with heights in some of the islands upper than 1800 m, that reach to 3718 m in the case of Tenerife island. Starting with the method of Cumulative Semivariograms1, already used to face the irradiation spatial interpolation problem, although not for a complex orography. In this sense, some major modifications are introduced to deal with our needs, which can be summarized as: a) interpolation of clearness index data (Kcd, defined as the division of the global horizontal data, between the corresponding clear sky global horizontal values, obtained from a suitable model) instead of solar irradiation data; b) topographic considerations are included in the clear sky model, such as topographics shadows. This impacts directly over direct component of solar irradiation, and has a minor effect over the diffuse component, arising from a non plane visible horizon; c) the meteorological stations are selected by a criteria of weather proximity, instead of geographic proximity as it was proposed in the original methodology of Cumulative Semivariograms; d) the final result is obtained as the composition of various maps obtained from error minimization within a neighborhood of each available station, instead of using irradiation isolines. A preliminary result with data registered only by Canary Islands Institute of Technology's stations, spread over the whole archipelago, is showed. From our results we can see both, the power of the developed methodology and some limitations due to the extremely complex orography as it is the case of Canary Islands, which consists of a wide variety of microclimate regions. Whenever additional information is available, either in the form of empiric knowledge of the local weather, or in the form of other available

Effects of Neutron Irradiation and Post-irradiation Annealing on the Microstructure of HT-UPS Stainless Steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Chi; Chen, Wei-Ying; Zhang, Xuan

Microstructural changes resulted from neutron irradiation and post-irradiation annealing in a high-temperature ultra-fine precipitate strengthened (HT-UPS) stainless steel were characterized using transmission electron microscopy (TEM) and atom probe tomography (APT). Three HT-UPS samples were neutron-irradiated to 3 dpa at 500 °C, and after irradiation, two of them were annealed for 1 h at 600 °C and 700 °C, respectively. Frank dislocation loops were the dominant defect structure in both the as-irradiated and 600 °C post-irradiation-annealed (PIAed) samples, and the loop sizes and densities were similar in these two samples. Unfaulted dislocation loops were observed in the 700 °C PIAed sample, and the loop density was greatly reducedmore » in comparison with that in the as-irradiated sample. Nano-sized MX precipitates were observed under TEM in the 700 °C PIAed sample, but not in the 600 °C PIAed or the as-irradiated samples. The titanium-rich clusters were identified in all three samples using APT. The post-irradiation annealing (PIA) caused the growth of the Ti-rich clusters with a stronger effect at 700 °C than at 600 °C. The irradiation caused elemental segregations at the grain boundary and the grain interior, and the grain boundary segregation behavior is consistent with observations in other irradiated austenitic steels. APT results showed that PIA reduced the magnitude of irradiation induced segregations.« less

Irradiation subassembly

DOEpatents

Seim, O.S.; Filewicz, E.C.; Hutter, E.

1973-10-23

An irradiation subassembly for use in a nuclear reactor is described which includes a bundle of slender elongated irradiation -capsules or fuel elements enclosed by a coolant tube and having yieldable retaining liner between the irradiation capsules and the coolant tube. For a hexagonal bundle surrounded by a hexagonal tube the yieldable retaining liner may consist either of six segments corresponding to the six sides of the tube or three angular segments each corresponding in two adjacent sides of the tube. The sides of adjacent segments abut and are so cut that metal-tometal contact is retained when the volume enclosed by the retaining liner is varied and Springs are provided for urging the segments toward the center of the tube to hold the capsules in a closely packed configuration. (Official Gazette)

Methods for routine control of irradiated food: Determination of the irradiation status of shellfish by thermoluminescence analysis

NASA Astrophysics Data System (ADS)

Schreiber, G. A.; Hoffmann, A.; Helle, N.; Bögl, K. W.

1994-06-01

In some countries, clearance has been given for treating certain types of shellfish by ionizing radiation in order to increase the shelf-life and to reduce health hazards which might be caused by contaminating microorganisms. In the present study, thermoluminescence (TL) analysis was used to examine the irradiation status of shellfish products purchased from local suppliers. For analysis minerals were isolated from the guts of the animals. Although on none of the examined products an irradiation treatment prior to analysis could be shown, the results obtained on non-irradiated and irradiated products have revealed that irradiation within the commercially used dose range can clearly be detected. Already first glow TL intensities of minerald indicated irradiation treatments. Normalized TL signals of non-irradiated and irradiated samples were clearly separated. By calculation of differences of TL intensities and TL signals between non-irradiated and irradiated samples in dependency of integration temperature an optimized integration area for glow curves was determined. The result of this study agree well with results obtained by two large-scale intercomparisons between food control laboratories to detect irradiation treatment of spices and herbal products as well as of fruit and vegetables by TL analysis of contaminating minerals.

Isoconversional approach for non-isothermal decomposition of un-irradiated and photon-irradiated 5-fluorouracil.

PubMed

Mohamed, Hala Sh; Dahy, AbdelRahman A; Mahfouz, Refaat M

2017-10-25

Kinetic analysis for the non-isothermal decomposition of un-irradiated and photon-beam-irradiated 5-fluorouracil (5-FU) as anti-cancer drug, was carried out in static air. Thermal decomposition of 5-FU proceeds in two steps. One minor step in the temperature range of (270-283°C) followed by the major step in the temperature range of (285-360°C). The non-isothermal data for un-irradiated and photon-irradiated 5-FU were analyzed using linear (Tang) and non-linear (Vyazovkin) isoconversional methods. The results of the application of these free models on the present kinetic data showed quite a dependence of the activation energy on the extent of conversion. For un-irradiated 5-FU, the non-isothermal data analysis indicates that the decomposition is generally described by A3 and A4 modeles for the minor and major decomposition steps, respectively. For a photon-irradiated sample of 5-FU with total absorbed dose of 10Gy, the decomposition is controlled by A2 model throughout the coversion range. The activation energies calculated in case of photon-irradiated 5-FU were found to be lower compared to the values obtained from the thermal decomposition of the un-irradiated sample probably due to the formation of additional nucleation sites created by a photon-irradiation. The decomposition path was investigated by intrinsic reaction coordinate (IRC) at the B3LYP/6-311++G(d,p) level of DFT. Two transition states were involved in the process by homolytic rupture of NH bond and ring secession, respectively. Published by Elsevier B.V.

Commercial implementation of food irradiation

NASA Astrophysics Data System (ADS)

Welt, M. A.

In July 1981, the first specifically designed multi-purpose irradiation facility for food irradiation was put into service by the Radiation Technology, Inc. subsidiary Process Technology, Inc. in West Memphis, Arkansas. The operational experience gained, resulted in an enhanced design which was put into commercial service in Haw River, North Carolina, by another subsidiary, Process Technology (N.C.), Inc. in October 1983. These facilities have enabled the food industry to assess the commercial viability of food irradiation. Further impetus towards commercialization of food irradiation was gained in March 1981 with the filing in the Federal Register, by the FDA, of an Advanced Proposed Notice of Rulemaking for Food Irradiation. Two years later in July 1983, the FDA approved the first food additive regulation involving food irradiation in nineteen years, when they approved the Radiation Technology, Inc. petition calling for the sanitization of spices, onion powder and garlic powder at a maximum dosage of 10 kGy. Since obtaining the spice irradiation approval, the FDA has accepted four additional petitions for filing in the Federal Register. One of the petitions which extended spice irradiation to include insect disinfestation has issued into a regulation while the remaining petitions covering the sanitization of herbs, spice blends, vegetable seasonings and dry powdery enzymes as well as the petition to irradiate hog carcasses and pork products for trichinae control at 1 kGy, are expected to issue either before the end of 1984 or early in 1985. More recently, food irradiation advocates in the United States received another vote of confidence by the announcement that a joint venture food irradiation facility to be constructed in Hawaii by Radiation Technology, is backed by a contractual committment for the processing of 40 million pounds of produce per year. Another step was taken when the Port of Salem, New Jersey announced that the Radiation Technology Model RT-4104

Final Report on MEGAPIE Target Irradiation and Post-Irradiation Examination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yong, Dai

2015-06-30

Megawatt pilot experiment (MEGAPIE) was successfully performed in 2006. One of the important goals of MEGAPIE is to understand the behaviour of structural materials of the target components exposed to high fluxes of high-energy protons and spallation neutrons in flowing LBE (liquid lead-bismuth eutectic) environment by conducting post-irradiation examination (PIE). The PIE includes four major parts: non-destructive test, radiochemical analysis of production and distribution of radionuclides produced by spallation reaction in LBE, analysis of LBE corrosion effects on structural materials, T91 and SS 316L steels, and mechanical testing of the T91 and SS 316L steels irradiated in the lower partmore » of the target. The non-destructive test (NDT) including visual inspection and ultrasonic measurement was performed in the proton beam window area of the T91 calotte of the LBE container, the most intensively irradiated part of the MEGAPIE target. The visual inspection showed no visible failure and the ultrasonic measurement demonstrated no detectable change in thickness in the beam window area. Gamma mapping was also performed in the proton beam window area of the AlMg 3 safety-container. The gamma mapping results were used to evaluate the accumulated proton fluence distribution profile, the input data for determining irradiation parameters. Radiochemical analysis of radionuclides produced by spallation reaction in LBE is to improve the understanding of the production and distribution of radionuclides in the target. The results demonstrate that the radionuclides of noble metals, 207Bi, 194Hg/Au are rather homogeneously distributed within the target, while radionuclides of electropositive elements are found to be deposited on the steel-LBE interface. The corrosion effect of LBE on the structural components under intensive irradiation was investigated by metallography. The results show that no evident corrosion damages. However, unexpected deep cracks were found in the

Effect of irradiation temperature on microstructural changes in self-ion irradiated austenitic stainless steel

NASA Astrophysics Data System (ADS)

Jin, Hyung-Ha; Ko, Eunsol; Lim, Sangyeob; Kwon, Junhyun; Shin, Chansun

2017-09-01

We investigated the microstructural and hardness changes in austenitic stainless steel after Fe ion irradiation at 400, 300, and 200 °C using transmission electron microscopy (TEM) and nanoindentation. The size of the Frank loops increased and the density decreased with increasing irradiation temperature. Radiation-induced segregation (RIS) was detected across high-angle grain boundaries, and the degree of RIS increases with increasing irradiation temperature. Ni-Si clusters were observed using high-resolution TEM in the sample irradiated at 400 °C. The results of this work are compared with the literature data of self-ion and proton irradiation at comparable temperatures and damage levels on stainless steels with a similar material composition with this study. Despite the differences in dose rate, alloy composition and incident ion energy, the irradiation temperature dependence of RIS and the size and density of radiation defects followed the same trends, and were very comparable in magnitude.

A stochastic post-processing method for solar irradiance forecasts derived from NWPs models

NASA Astrophysics Data System (ADS)

Lara-Fanego, V.; Pozo-Vazquez, D.; Ruiz-Arias, J. A.; Santos-Alamillos, F. J.; Tovar-Pescador, J.

2010-09-01

Solar irradiance forecast is an important area of research for the future of the solar-based renewable energy systems. Numerical Weather Prediction models (NWPs) have proved to be a valuable tool for solar irradiance forecasting with lead time up to a few days. Nevertheless, these models show low skill in forecasting the solar irradiance under cloudy conditions. Additionally, climatic (averaged over seasons) aerosol loading are usually considered in these models, leading to considerable errors for the Direct Normal Irradiance (DNI) forecasts during high aerosols load conditions. In this work we propose a post-processing method for the Global Irradiance (GHI) and DNI forecasts derived from NWPs. Particularly, the methods is based on the use of Autoregressive Moving Average with External Explanatory Variables (ARMAX) stochastic models. These models are applied to the residuals of the NWPs forecasts and uses as external variables the measured cloud fraction and aerosol loading of the day previous to the forecast. The method is evaluated for a set one-moth length three-days-ahead forecast of the GHI and DNI, obtained based on the WRF mesoscale atmospheric model, for several locations in Andalusia (Southern Spain). The Cloud fraction is derived from MSG satellite estimates and the aerosol loading from the MODIS platform estimates. Both sources of information are readily available at the time of the forecast. Results showed a considerable improvement of the forecasting skill of the WRF model using the proposed post-processing method. Particularly, relative improvement (in terms of the RMSE) for the DNI during summer is about 20%. A similar value is obtained for the GHI during the winter.

Irradiation Creep in Graphite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ubic, Rick; Butt, Darryl; Windes, William

2014-03-13

An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarlymore » characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.« less

Thermoluminescence of irradiated foodstuffs

NASA Astrophysics Data System (ADS)

Oduko, J. M.; Spyrou, N. M.

Measurements have been made of the thermoluminescent response of a number of foodstuffs, namely spices, chicken bone, eggshell and strawberries. From the results, irradiated samples can be clearly distinguished from unirradiated ones for several weeks after irradiation of 5-10 kGy, or in the case of some spices for up to 20 months. It is concluded that measurement of thermoluminescence is a promising technique for detecting the irradiation of foodstuffs.

Irradiation effects in monazite-(Ce) and zircon: Raman and photoluminescence study of Au-irradiated FIB foils

NASA Astrophysics Data System (ADS)

Nasdala, Lutz; Akhmadaliev, Shavkat; Artac, Andreas; Chanmuang N., Chutimun; Habler, Gerlinde; Lenz, Christoph

2018-05-01

Lamellae of 1.5 µm thickness, prepared from well-crystallised monazite-(Ce) and zircon samples using the focused-ion-beam technique, were subjected to triple irradiation with 1 MeV Au+ ions (15.6% of the respective total fluence), 4 MeV Au2+ ions (21.9%) and 10 MeV Au3+ ions (62.5%). Total irradiation fluences were varied in the range 4.5 × 1012 - 1.2 × 1014 ions/cm2. The highest fluence resulted in amorphisation of both minerals; all other irradiations (i.e. up to 4.5 × 1013 ions/cm2) resulted in moderate to severe damage. Lamellae were subjected to Raman and laser-induced photoluminescence analysis, in order to provide a means of quantifying irradiation effects using these two micro-spectroscopy techniques. Based on extensive Monte Carlo calculations and subsequent defect-density estimates, irradiation-induced spectroscopic changes are compared with those of naturally self-irradiated samples. The finding that ion irradiation of monazite-(Ce) may cause severe damage or even amorphisation, is in apparent contrast to the general observation that naturally self-irradiated monazite-(Ce) does not become metamict (i.e. irradiation-amorphised), in spite of high self-irradiation doses. This is predominantly assigned to the continuous low-temperature damage annealing undergone by this mineral; other possible causes are discussed. According to cautious estimates, monazite-(Ce) samples of Mesoproterozoic to Cretaceous ages have stored only about 1% of the total damage experienced. In contrast, damage in ion-irradiated and naturally self-irradiated zircon is on the same order; reasons for the observed slight differences are discussed. We may assess that in zircon, alpha decays create significantly less than 103 Frenkel-type defect pairs per event, which is much lower than previous estimates. Amorphisation occurs at defect densities of about 0.10 dpa (displacements per lattice atom).

CYCLIC THERMAL SIGNATURE IN A GLOBAL MHD SIMULATION OF SOLAR CONVECTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cossette, Jean-Francois; Charbonneau, Paul; Smolarkiewicz, Piotr K.

Global magnetohydrodynamical simulations of the solar convection zone have recently achieved cyclic large-scale axisymmetric magnetic fields undergoing polarity reversals on a decadal time scale. In this Letter, we show that these simulations also display a thermal convective luminosity that varies in-phase with the magnetic cycle, and trace this modulation to deep-seated magnetically mediated changes in convective flow patterns. Within the context of the ongoing debate on the physical origin of the observed 11 yr variations in total solar irradiance, such a signature supports the thesis according to which all, or part, of the variations on decadal time scales and longermore » could be attributed to a global modulation of the Sun's internal thermal structure by magnetic activity.« less

Development of radiation indicators to distinguish between irradiated and non-irradiated herbal medicines using HPLC and GC-MS.

PubMed

Kim, Min Jung; Ki, Hyeon A; Kim, Won Young; Pal, Sukdeb; Kim, Byeong Keun; Kang, Woo Suk; Song, Joon Myong

2010-09-01

The effects of high dose γ-irradiation on six herbal medicines were investigated using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). Herbal medicines were irradiated at 0-50 kGy with (60)Co irradiator. HPLC was used to quantify changes of major components including glycyrrhizin, cinnamic acid, poncirin, hesperidin, berberine, and amygdalin in licorice, cinnamon bark, poncirin immature fruit, citrus unshiu peel, coptis rhizome, and apricot kernel. No significant differences were found between gamma-irradiated and non-irradiated samples with regard to the amounts of glycyrrhizin, berberine, and amygdalin. However, the contents of cinnamic acid, poncirin, and hesperidin were increased after irradiation. Volatile compounds were analyzed by GC/MS. The relative proportion of ketone in licorice was diminished after irradiation. The relative amount of hydrocarbons in irradiated cinnamon bark and apricot kernel was higher than that in non-irradiated samples. Therefore, ketone in licorice and hydrocarbons in cinnamon bark and apricot kernel can be considered radiolytic markers. Three unsaturated hydrocarbons, i.e., 1,7,10-hexadecatriene, 6,9-heptadecadiene, and 8-heptadecene, were detected only in apricot kernels irradiated at 25 and 50 kGy. These three hydrocarbons could be used as radiolytic markers to distinguish between irradiated (>25 kGy) and non-irradiated apricot kernels.

Irradiated ready-to-eat spinach leaves: How information influences awareness towards irradiation treatment and consumer's purchase intention

NASA Astrophysics Data System (ADS)

Finten, G.; Garrido, J. I.; Agüero, M. V.; Jagus, R. J.

2017-01-01

This article aims to clarify and supply further information on food irradiation acceptance, with particular focus on Argentina and irradiated ready-to-eat (RTE) spinach leaves through an open web-online survey. Results showed that half of respondents did not know food irradiation, but the other half demonstrated uncertainty despite they declared they had knowledge about it; thus, confirming little awareness towards this technology. Respondents who believed in the misleading myth about food irradiation represented 39%, while roughly the same number was doubtful. On the other hand, after supplying informative material, respondents were positively influenced and an increase in acceptance by 90% was found. Finally, 42% of respondents were willing to consume/purchase irradiated RTE spinach leaves, and 35% remained doubtful. Respondents who did not exclude to accept irradiated spinach could be considered potential consumers if intensive campaigns about the benefits of food irradiation were carried out by reliable actors. If the Argentinean RTE market grew, following the world consumption trend towards these products, irradiated spinach leaves could be successfully introduced by making better efforts to inform consumers about food irradiation.

Irradiation stability and thermo-mechanical properties of NITE-SiC irradiated to 10 dpa

DOE PAGES

Terrani, Kurt A.; Ang, Caen; Snead, Lance L.; ...

2017-11-24

In this study, five variants of nano-infiltration transient eutectic (NITE) SiC were prepared using nanopowder feedstock and sintering additive contents of <10 wt%. The dense monolithic materials were subsequently irradiated to 2 and 10 dpa in a mixed spectrum fission reactor at nominally 400 and 700°C. The evolution in swelling, strength, and thermal conductivity of these materials were examined after irradiation, where in all cases properties saturated at < 2dpa, without appreciable change for further irradiation to 10 dpa. Swelling behavior appeared similar to high-purity chemical vapor deposition (CVD) SiC within measurement uncertainty. The strength roughly doubled after irradiation. Finally,more » thermal resistivity increase as a result of irradiation was ~20% higher when compared to CVD-SiC.« less

Irradiation stability and thermo-mechanical properties of NITE-SiC irradiated to 10 dpa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terrani, Kurt A.; Ang, Caen; Snead, Lance L.

In this study, five variants of nano-infiltration transient eutectic (NITE) SiC were prepared using nanopowder feedstock and sintering additive contents of <10 wt%. The dense monolithic materials were subsequently irradiated to 2 and 10 dpa in a mixed spectrum fission reactor at nominally 400 and 700°C. The evolution in swelling, strength, and thermal conductivity of these materials were examined after irradiation, where in all cases properties saturated at < 2dpa, without appreciable change for further irradiation to 10 dpa. Swelling behavior appeared similar to high-purity chemical vapor deposition (CVD) SiC within measurement uncertainty. The strength roughly doubled after irradiation. Finally,more » thermal resistivity increase as a result of irradiation was ~20% higher when compared to CVD-SiC.« less

Deployment and early results from the CanSIM (Canadian Solar Spectral Irradiance Meter) network

NASA Astrophysics Data System (ADS)

Tatsiankou, Viktar; Hinzer, Karin; Schriemer, Henry; McVey-White, Patrick; Beal, Richard

2017-09-01

Three of seven stations have been deployed as part of the Canadian Solar Spectral Irradiance (CanSIM) network situated in Ottawa, Varennes and Egbert to measure long term spectral variation of the direct normal (DNI) and global horizontal irradiances (GHI) across the country. Every station is equipped with a solar tracker, SolarSIM-D2+, SolarSIM-G+, and SR20 pyranometer, reporting the spectral DNI, GHI, diffuse horizontal irradiance (DHI) and aerosol optical depth in the 280-4000 nm range, broadband DNI, GHI, and DHI, atmospheric total column ozone and water vapour amounts. The spectral GHI as measured by the SolarSIM-G+ was within 5% as compared to EKO MS-700 spectroradiometer in 350-1050 nm range on 17 March 2017. The difference in the GHI as reported by SolarSIM-G+ and SR20 pyranometer from all stations was within 2% on 14 April 2017. Furthermore, on this day, the daily GHI sum for the Ottawa, Varennes, and Egbert stations was 7.01, 6.95, and 7.11 kWh/m2, respectively, while the daily DNI sum was 10.65, 10.86, 10.04 kWh/m2, respectively.

How to improve the irradiation conditions for the International Fusion Materials Irradiation Facility

NASA Astrophysics Data System (ADS)

Daum, Eric

2000-12-01

The accelerator-based intense D-Li neutron source International Fusion Materials Irradiation Facility (IFMIF) provides very suitable irradiation conditions for fusion materials development with the attractive option of accelerated irradiations. Investigations show that a neutron moderator made of tungsten and placed in the IFMIF test cell can further improve the irradiation conditions. The moderator softens the IFMIF neutron spectrum by enhancing the fraction of low energy neutrons. For displacement damage, the ratio of point defects to cascades is more DEMO relevant and for tritium production in Li-based breeding ceramic materials it leads to a preferred production via the 6Li(n,t) 4He channel as it occurs in a DEMO breeding blanket.

High resolution laser beam induced current images under trichromatic laser radiation: approximation to the solar irradiation.

PubMed

Navas, F J; Alcántara, R; Fernández-Lorenzo, C; Martín-Calleja, J

2010-03-01

A laser beam induced current (LBIC) map of a photoactive surface is a very useful tool when it is necessary to study the spatial variability of properties such as photoconverter efficiency or factors connected with the recombination of carriers. Obtaining high spatial resolution LBIC maps involves irradiating the photoactive surface with a photonic beam with Gaussian power distribution and with a low dispersion coefficient. Laser emission fulfils these characteristics, but against it is the fact that it is highly monochromatic and therefore has a spectral distribution different to solar emissions. This work presents an instrumental system and procedure to obtain high spatial resolution LBIC maps in conditions approximating solar irradiation. The methodology developed consists of a trichromatic irradiation system based on three sources of laser excitation with emission in the red, green, and blue zones of the electromagnetic spectrum. The relative irradiation powers are determined by either solar spectrum distribution or Planck's emission formula which provides information approximate to the behavior of the system if it were under solar irradiation. In turn, an algorithm and a procedure have been developed to be able to form images based on the scans performed by the three lasers, providing information about the photoconverter efficiency of photovoltaic devices under the irradiation conditions used. This system has been checked with three photosensitive devices based on three different technologies: a commercial silicon photodiode, a commercial photoresistor, and a dye-sensitized solar cell. These devices make it possible to check how the superficial quantum efficiency has areas dependent upon the excitation wavelength while it has been possible to measure global incident photon-to-current efficiency values approximating those that would be obtained under irradiation conditions with sunlight.

Survival after total body irradiation: Effects of irradiation of exteriorized small intestine. (Reannouncement with new availability information)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vriesendorp, H.M.; Vigneulle, R.M.; Kitto, G.

1993-12-31

Rats receiving lethal irradiation to their exteriorized small intestine with pulsed 18 MVp bremsstrahlung radiation live about 4 days longer than rats receiving a dose of total-body irradiation (TBI) causing intestinal death. The LD50 for intestinal irradiation is approximately 6 Gy higher than the LD50 for intestinal death after TBI. Survival time after exteriorized intestinal irradiation can be decreased, by adding abdominal irradiation. Adding thoracic or pelvic irradiation does not alter survival time. Shielding of large intestine improves survival after irradiation of the rest of the abdomen while the small intestine is also shielded. The kinetics of histological changes inmore » small intestinal tissues implicate the release of humoral factors after irradiation of the abdomen. Radiation injury develops faster in the first (proximal) 40 cm of the small intestine and is expressed predominantly as shortening in villus height. In the last (distal) 40 cm of the small intestine, the most pronounced radiation effect is a decrease in the number of crypts per millimeter. Irradiation (20 Gy) of the proximal small intestine causes 92 % mortality (median survival 10 days). Irradiation (20 Gy) of the distal small intestine causes 27% mortality (median survival > 30 days). In addition to depletion of crypt stem cells in the small intestine, other issues (humoral factors, irradiated subsection of the small intestine and shielding of the large intestine) appear to influence radiation-induced intestinal mortality.« less

TU-H-CAMPUS-TeP2-02: FLASH Irradiation Improves the Therapeutic Index Following GI Tract Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schueler, E; Trovati, S; King, G

Purpose: To investigate and characterize the radiobiological effectiveness of very high dose rate radiotherapy (FLASH) compared to conventional irradiation in an in vivo model. Methods: The gastrointestinal (GI) tract of C57BL/6 mice were irradiated with doses ranging between 10 and 18 Gy using a custom stereotactic jig. A Varian Clinac 21EX was modified to allow dose rates ranging from 0.05 to 240 Gy/s at the position of the mirror. With the gantry at 180 degrees, the jig holding the individual animals was placed above the mirror to take advantage of the reduced source to target distance. Mice were irradiated withmore » 20MeV electrons. Following irradiation, the mice were monitored twice daily for morbidity and daily for weight changes. Results: Mice irradiated with FLASH irradiation had lower weight loss compared to the mice receiving conventional irradiation. Following FLASH irradiation, a maximum weight loss of ∼20% was observed at day 6 with subsequent recovery, while following conventional irradiation, higher weight losses was observed with fewer instances of recovery. Concerning survival, all mice in the conventionally irradiated groups had a 100% mortality in the range of 15.5–18 Gy, while the mice irradiated with FLASH irradiation had a 100% survival in the same range. Conclusion: These results have demonstrated proof of principle that FLASH irradiations have a dramatic impact on the overall survival of mice following GI tract irradiations. If the increase in the therapeutic window can be validated and understood, this would revolutionize the field of radiation oncology and lead to increased cure rates with reduced side effects following treatment, resulting in increased quality of life for cancer survivors. Funding: DoD, Award#:W81XWH-14-1-0014, Weston Havens Foundation, Bio-X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation; BL and PM

Blood Irradiator Interactive Tool Beta Version

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howington, John; Potter, Charles; DeGroff, Tavias

The “Blood Irradiator Interactive Tool” compares a typical Cs-137 Blood Irradiator with that of the capabilities of an average X-ray Irradiator. It is designed to inform the user about the potential capabilities that an average X-ray Irradiator could offer them. Specifically the tool compares the amount of blood bags that can be irradiated by the users’ machine with that of the average X-ray capability. It also forcasts the amount of blood that can be irradiated on yearly basis for both the users’ machine and an average X-ray Device. The Average X-ray capabilities are taken from the three X-ray devices currentlymore » on the market: The RS 3400 Rad Source X-ray Blood Irradiator and both the 2.0L and 3.5 L versions of the Best Theratronis Raycell MK2« less

IRRADIATION AND TISSUE IMMUNITY. II. RESPONSE TO INJECTION OF STAPHYLOCOCCI IN X IRRADIATED SKIN AREAS OF RABBITS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kahn, R.L.

1963-03-01

Twenty-four hrs after 1000-r x irradiation of a small area of the skin of rabbits, they were injected with a suspension of staphylococci subcutaneously in the irradiated area and in a nonirradiated control area. Localized lesions were most marked in nonirradiated areas and in some animals no visible lesions were noted in irradiated areas. The mild inflammatory lesions in irradiated areas corroborate the point of view, that irradiation is anti-inflammatory. The reason for mild lesions must be the reduced localization of staphylococci in irradiated areas and their escape from those areas. It is suggested that the antilocalizing property of irradiationmore » is probably the basis for the antiinflammatory action. When the concentration of organisms injected in the irradiated area was high (10 billion), septicemia and death of the rabbits occurred, presumably as a result of the antilocalizing property of irradiation, which permitted the escape of the organisms from the injected area. In animals injected in irradiated areas with either 0.5 or 5 billion organisms, no septicemia was observed, presumably because of the high natural immunity of rabbits to staphylococci. (TCO)« less

Pyruvate kinase M2 interacts with DNA damage-binding protein 2 and reduces cell survival upon UV irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Xiao; Wang, Mingsong; Mei, Ju, E-mail: jumei_xinhua@163.com

Pyruvate Kinase M2 (PKM2) is highly expressed in many solid tumors and associated with metabolism reprogramming and proliferation of tumors. Here, we report that PKM2 can bind to DNA Damage-Binding Protein 2 (DDB2), which is necessary for global nucleotide excision repair of UV induced DNA damage. The binding is promoted by UV irradiation and K433 acetylation of PKM2. Over expression of PKM2 facilitates phosphorylation of DDB2 and impairs DDB2-DDB1 binding. Furthermore, knocking down of PKM2 increases cell survival upon UV irradiation, while over expression of PKM2 reduces cell survival and over expression of DDB2-DDB1 reverts this effect. These results revealmore » a previously unknown regulation of PKM2 on DDB2 and provide a possible mechanism for UV induced tumorigenesis. - Highlights: • PKM2 interacts with DDB2. • UV irradiation increases PKM2-DDB2 binding via up regulation of PKM2 K433 acetylation. • PKM2 facilitates DDB2 phosphorylation and impairs DDB2-DDB1 binding. • PKM2 reduces cell survival upon UV irradiation.« less

Estimating solar ultraviolet irradiance (290-385 nm) by means of the spectral parametric models: SPCTRAL2 and SMARTS2

NASA Astrophysics Data System (ADS)

Foyo-Moreno, I.; Vida, J.; Olmo, F. J.; Alados-Arboledas, L.

2000-11-01

Since the discovery of the ozone depletion in Antarctic and the globally declining trend of stratospheric ozone concentration, public and scientific concern has been raised in the last decades. A very important consequence of this fact is the increased broadband and spectral UV radiation in the environment and the biological effects and heath risks that may take place in the near future. The absence of widespread measurements of this radiometric flux has lead to the development and use of alternative estimation procedures such as the parametric approaches. Parametric models compute the radiant energy using available atmospheric parameters. Some parametric models compute the global solar irradiance at surface level by addition of its direct beam and diffuse components. In the present work, we have developed a comparison between two cloudless sky parametrization schemes. Both methods provide an estimation of the solar spectral irradiance that can be integrated spectrally within the limits of interest. For this test we have used data recorded in a radiometric station located at Granada (37.180°N, 3.580°W, 660 m a.m.s.l.), an inland location. The database includes hourly values of the relevant variables covering the years 1994-95. The performance of the models has been tested in relation to their predictive capability of global solar irradiance in the UV range (290-385 nm). After our study, it appears that information concerning the aerosol radiative effects is fundamental in order to obtain a good estimation. The original version of SPCTRAL2 provides estimates of the experimental values with negligible mean bias deviation. This suggests not only the appropriateness of the model but also the convenience of the aerosol features fixed in it to Granada conditions. SMARTS2 model offers increased flexibility concerning the selection of different aerosol models included in the code and provides the best results when the selected models are those considered as urban

AGC-2 Irradiation Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rohrbaugh, David Thomas; Windes, William; Swank, W. David

The Next Generation Nuclear Plant (NGNP) will be a helium-cooled, very high temperature reactor (VHTR) with a large graphite core. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor (HTGR) designs.[ , ] Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphites have been developed and are considered suitable candidates for the new NGNP reactor design. To support the design and licensing of NGNP core components within a commercial reactor, a completemore » properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade with a specific emphasis on data related to the life limiting effects of irradiation creep on key physical properties of the NGNP candidate graphites. Based on experience with previous graphite core components, the phenomenon of irradiation induced creep within the graphite has been shown to be critical to the total useful lifetime of graphite components. Irradiation induced creep occurs under the simultaneous application of high temperatures, neutron irradiation, and applied stresses within the graphite components. Significant internal stresses within the graphite components can result from a second phenomenon—irradiation induced dimensional change. In this case, the graphite physically changes i.e., first shrinking and then expanding with increasing neutron dose. This disparity in material volume change can induce significant internal stresses within graphite components. Irradiation induced creep relaxes these large internal stresses, thus reducing the risk of crack formation and component failure. Obviously, higher irradiation creep levels tend to relieve more internal stress, thus allowing the

MASSIVE LEAKAGE IRRADIATOR

DOEpatents

Wigner, E.P.; Szilard, L.; Christy, R.F.; Friedman, F.L.

1961-05-30

An irradiator designed to utilize the neutrons that leak out of a reactor around its periphery is described. It avoids wasting neutron energy and reduces interference with the core flux to a minimum. This is done by surrounding all or most of the core with removable segments of the material to be irradiated within a matrix of reflecting material.

Positron irradiation effect on positronium formation in gamma-irradiated LDPE and unplasticized PVC

NASA Astrophysics Data System (ADS)

Yang, J.; Zang, P.; Cao, X. Z.; Yu, R. S.; Wang, B. Y.

2017-06-01

Positron irradiation effects on positronium formation in low-density polyethylene (LDPE), gamma-irradiated LDPE and unplasticized PVC (UPVC) are studied. At least in one of the three different measurements, i.e., prolonged positron annihilation measurement at room temperature, low temperature in darkness and subsequent measurement under light, changes in o-Ps intensity are observed in non-irradiated LDPE and gamma-irradiated LDPE. While in UPVC, change in o-Ps intensity is hardly observable in all the above-mentioned three measurements. Reduction of o-Ps intensity by light indicates that positronium formation via the recombination of a positron and a trapped electron exists in LDPE and gamma-irradiated LDPE. The absence of light bleaching effect, together with the fact that the value of o-Ps intensity in heating and cooling process of a thermal circle is nearly the same, indicates that in UPVC, positronium can not be formed through trapped electron mechanism. This study highlights the speciality of positronium formation in UPVC, positronium is formed exclusively by the recombination of electron-positron pairs with short separations.

A new multipurpose gamma-irradiation facility

NASA Astrophysics Data System (ADS)

Huebner, G.

In the past 3 yr much work has been done in the G.D.R. on food irradiation. The experiments have shown that this treatment gives favourable results in many products such as spices, onions, potatoes, chicken, animal feeds, fodder yeast, drugs and vaccines. Economic aspects of food irradiation require the effective use of an irradiation plant and cobalt-60. Therefore, a new multipurpose irradiation facility was developed, applicable as an onion irradiator with a capacity of about 15 ton/h and for the simultaneous irradiation of different products (spices, animal feed, chicken, etc.) in closed product ☐es with a size of 1.2 m x 1.0 m x 1.2 m. A microcomputer controls the transport of product ☐es around the gamma sources.

Recent Trends in Global Ocean Chlorophyll

NASA Technical Reports Server (NTRS)

Gregg, Watson; Casey, Nancy

2004-01-01

Recent analyses of SeaWiFS data have shown that global ocean chlorophyll has increased more than 5% since 1998. The North Pacific ocean basin has increased nearly 19%. To understand the causes of these trends we have applied the newly developed NASA Ocean Biogeochemical Assimilation Model (OBAM), which is driven in mechanistic fashion by surface winds, sea surface temperature, atmospheric iron deposition, sea ice, and surface irradiance. The mode1 utilizes chlorophyll from SeaWiFS in a daily assimilation. The model has in place many of the climatic variables that can be expected to produce the changes observed in SeaWiFS data. Ths enables us to diagnose the model performance, the assimilation performance, and possible causes for the increase in chlorophyll.

Solar Irradiance Data Products at the LASP Interactive Solar IRradiance Datacenter (LISIRD)

NASA Astrophysics Data System (ADS)

Ware Dewolfe, A.; Wilson, A.; Lindholm, D. M.; Pankratz, C. K.; Snow, M. A.; Woods, T. N.

2010-12-01

The Laboratory for Atmospheric and Space Physics (LASP) has developed the LASP Interactive Solar IRradiance Datacenter (LISIRD) to provide access to a comprehensive set of solar irradiance measurements. LISIRD has recently been updated to serve many new datasets and models, including data from SORCE, UARS-SOLSTICE, SME, and TIMED-SEE, and model data from the Flare Irradiance Spectral Model (FISM). The user interface emphasizes web-based interactive visualizations, allowing users to explore and compare this data before downloading it for analysis. The data provided covers a wavelength range from soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as wavelength-independent Total Solar Irradiance (TSI). Combined data from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments provide continuous coverage from 1981 to the present, while Lyman-alpha measurements, FISM daily data, and TSI models date from the 1940s to the present. LISIRD will also host Glory TSI data as part of the SORCE data system. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD’s interfaces.

Proton irradiation impacts age-driven modulations of cancer progression influenced by immune system transcriptome modifications from splenic tissue.

PubMed

Wage, Justin; Ma, Lili; Peluso, Michael; Lamont, Clare; Evens, Andrew M; Hahnfeldt, Philip; Hlatky, Lynn; Beheshti, Afshin

2015-09-01

Age plays a crucial role in the interplay between tumor and host, with additional impact due to irradiation. Proton irradiation of tumors induces biological modulations including inhibition of angiogenic and immune factors critical to 'hallmark' processes impacting tumor development. Proton irradiation has also provided promising results for proton therapy in cancer due to targeting advantages. Additionally, protons may contribute to the carcinogenesis risk from space travel (due to the high proportion of high-energy protons in space radiation). Through a systems biology approach, we investigated how host tissue (i.e. splenic tissue) of tumor-bearing mice was altered with age, with or without whole-body proton exposure. Transcriptome analysis was performed on splenic tissue from adolescent (68-day) versus old (736-day) C57BL/6 male mice injected with Lewis lung carcinoma cells with or without three fractionations of 0.5 Gy (1-GeV) proton irradiation. Global transcriptome analysis indicated that proton irradiation of adolescent hosts caused significant signaling changes within splenic tissues that support carcinogenesis within the mice, as compared with older subjects. Increases in cell cycling and immunosuppression in irradiated adolescent hosts with CDK2, MCM7, CD74 and RUVBL2 indicated these were the key genes involved in the regulatory changes in the host environment response (i.e. the spleen). Collectively, these results suggest that a significant biological component of proton irradiation is modulated by host age through promotion of carcinogenesis in adolescence and resistance to immunosuppression, carcinogenesis and genetic perturbation associated with advancing age. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Electron irradiation of dry food products

NASA Astrophysics Data System (ADS)

Grünewald, Th.

The interest of the industrial food producer is increasing in having the irradiation facility installed in the food processing chain. The throughput of the irradiator should be high and the residence time of the product in the facility should be short. These conditions can be accomplished by electron irradiators. To clarify the irradiation conditions spices taken out of the industrial process, food grade salt, sugar, and gums as models of dry food products were irradiated. With a radiation dose of 10 kGy microbial load can be reduced on 10∗∗4 microorganisms/g. The sensory properties of the spices were not changed in an atypical way. For food grade salt and sugar changes of colour were observed which are due to lattice defects or initiated browning. The irradiation of several gums led only in some cases to an improvement of the thickness properties in the application below 50°C, in most cases the thickness effect was reduced. The products were packaged before irradiation. But it would be possible also to irradiate the products without packaging moving the product through the iradiation field in a closed conveyor system.

Cherry Irradiation Studies. 1984 annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eakin, D.E.; Hungate, F.P.; Tingey, G.L.

1985-04-01

Fresh cherries, cherry fruit fly larvae, and codling moth larvae were irradiated using the PNL cobalt-60 facility to determine the efficacy of irradiation treatment for insect disinfestation and potential shelf life extension. Irradiation is an effective disinfestation treatment with no significant degradation of fruit at doses well above those required for quarantine treatment. Sufficient codling moth control was achieved at projected doses of less than 25 krad; cherry fruit fly control, at projected doses of less than 15 krad. Dose levels up to 60 krad did not adversely affect cherry quality factors tested. Irradiation above 60 krad reduced the firmnessmore » of cherries but had no significant impact on other quality factors tested. Irradiation of cherries below 80 krad did not result in any significant differences in sensory evaluations (appearance, flavor, and firmness) in tests conducted at OSU. Irradiation up to 200 krad at a temperature of about 25/sup 0/C (77/sup 0/F) did not measurably extend shelf life. Irradiation at 500 krad at 25/sup 0/C (77/sup 0/F) increased mold and rotting of cherries tested. There is no apparent advantage of irradiation over low-temperature fumigation.« less

UV spectral irradiance measurements in New Zealand: Effects of Pinatubo volcanic aerosol

NASA Technical Reports Server (NTRS)

Mckenzie, Richard L.

1994-01-01

Since late 1989, regular UV spectral irradiance measurements have been made at Lauder, New Zealand (45 deg S, 170 deg E), whenever weather permits. Here, the instrumentation and measurement strategy are outlined, and early results are discussed. Following the eruption of Mt Pinatubo in June 1991, large amounts of volcanic aerosol were injected into the stratosphere and were subsequently transported to New Zealand's latitudes in the latter half of 1991. This provides an opportunity to investigate the effects of volcanic aerosols on UV irradiances measured at this clean-air site. Although changes in global (sum of diffuse plus direct) irradiances were below the detection threshold, there were significant changes in the partitioning of radiation between the direct beam and diffuse skylight. Decreases by nearly a factor of two in the direct/diffuse ratio were observed at longer wavelengths, and at smaller solar zenith angles (sza's). The aerosol optical depth due to volcanic aerosol over Lauder in December 1991 was 0.15 plus or minus 0.02 at 450 nm, with lower values at shorter wavelengths. Although effects were relatively small in the UVB region, an implication of the changes is that the contrast between shade and direct sun is reduced, so that shaded areas received relatively more radiation in the summer of 1991/92 in New Zealand.

Clear-sky irradiance simulation using GMAO products and its comparison to ground and CERES satellite observation

NASA Astrophysics Data System (ADS)

Ham, S. H.; Loeb, N. G.; Kato, S.; Rose, F. G.; Bosilovich, M. G.; Rutan, D. A.; Huang, X.; Collow, A.

2017-12-01

Global Modeling Assimilation Office (GMAO) GEOS assimilated datasets are used to describe temperature and humidity profiles in the Clouds and the Earth's Radiant Energy System (CERES) data processing. Given that advance versions of the assimilated data sets known as of Forward Processing (FP), FP Parallel (FPP), and Modern-Era Retrospective Analysis for Research and Applications version 2 (MERRA-2) datasets are available, we examine clear-sky irradiance calculation to see if accuracy is improved with these newer versions of GMAO datasets when their temperature and humidity profiles are used in computing irradiances. Two older versions, GEOS-5.2.0 and GEOS-5.4.1 are used for producing, respectively, Ed3 and Ed4 CERES data products. For the evaluation, CERES-derived TOA irradiances and observed ground-based surface irradiances are compared with the computed irradiances for clear skies identified by Moderate Resolution Imaging Spectroradiometer (MODIS). Surface type dependent spectral emissivity is taken from an observationally-based monthly gridded emissivity dataset. TOA longwave (LW) irradiances computed with GOES-5.2.0 temperature and humidity profiles are biased low, up to -5 Wm-2, compared to CERES-derived TOA longwave irradiance over tropical oceans. In contrast, computed longwave irradiances agree well with CERES observations with the biases less than 2 W m-2 when GOES-5.4.1, FP v5.13, or MERRA-2 temperature and humidity are used. The negative biases of the TOA LW irradiance computed with GOES-5.2.0 appear to be related to a wet bias at 500-850 hPa layer. This indicates that if the input of CERES algorithm switches from GOES-5.2.0 to FP v5.13 or MERRA-2, the bias in clear-sky longwave TOA fluxes over tropical oceans is expected to be smaller. At surface, downward LW irradiances computed with FP v5.13 and MERRA-2 are biased low, up to -10 Wm-2, compared to ground observations over tropical oceans. The magnitude of the bias in the longwave surface irradiances

Irradiation of northwest agricultural products

NASA Astrophysics Data System (ADS)

Eakin, D. E.; Tingey, G. I.

1985-02-01

Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect ocntrol procedures are developed and followed. Due to the recognized potential benefits of irradiation, this program was conducted to evaluate the benefits of using irradiation on Northwest agricultural products. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

An Estimate of Changes in the Sun's Total Irradiance Caused by UV Irradiance Variations from 1874 to 1988

NASA Technical Reports Server (NTRS)

Lean, J.

1990-01-01

Enhanced emission from bright solar faculae is a source of significant variation in the sun's total irradiance. Relative to the emission from the quiet sun, facular emission is known to be considerably greater at UV wavelengths than at visible wavelengths. Determining the spectral dependence of facular emission is of interest for the physical insight this may provide to the origin of the sun's irradiance variations. It is also of interest because solar radiation at lambda less than 300 nm is almost totally absorbed in the Earth's atmosphere. Depending on the magnitude of the UV irradiance variations, changes in the sun's irradiance that penetrates to the Earth's surface may not be equivalent to total irradiance variations measured above the Earth's atmosphere. Using an empirical model of total irradiance variations which accounts separately for changes caused by bright faculae from those associated with dark sunspots, the contribution of UV irradiance variations to changes in the sun's total irradiance is estimated during solar cycles 12 to 21.

Dyeing of γ-irradiated cotton with natural flavonoid dye extracted from irradiated onion shells (Allium cepa) powder

NASA Astrophysics Data System (ADS)

Rehman, Fazal-ur; Adeel, Shahid; Shahid, Muhammad; Bhatti, Ijaz Ahmad; Nasir, Faiza; Akhtar, Nasim; Ahmad, Zulfiqar

2013-11-01

Powder of Onion shells as a source of natural flavonoid dye (Quercetin) and cotton fabrics were exposed to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Irradiated and un-irradiated dye powder was used for extraction of quercetin as well as antibacterial, hemolytic and antioxidant activities were also determined to observe the effect of radiation. Furthermore, color strength and colourfastness of irradiated fabrics were improved by using pre and post-mordants such as alum and iron. It is found that 4 kGy is the optimal absorbed dose for extraction of natural quercetin extracted from onion shells while maximum color strength and acceptable fastness properties are obtained on dyeing of irradiated fabric at 60 °C keeping M:L of 1:30 using 10% alum as pre-mordant and 6% alum as post-mordant. Gamma irradiation has not only improved the color strength of the dye using irradiated cotton but also that of colourfastness properties.

Annealing characteristics of amorphous silicon alloy solar cells irradiated with 1.00 MeV protons

NASA Technical Reports Server (NTRS)

Abdulaziz, Salman S.; Woodyard, James R.

1991-01-01

Amorphous Si:H and amorphous Si sub x, Ge sub (1-x):H solar cells were irradiated with 1.00 MeV proton fluences in the range of 1.00E14 to 1.25E15 cm (exp -2). Annealing of the short circuit current density was studied at 0, 22, 50, 100, and 150 C. Annealing times ranged from an hour to several days. The measurements confirmed that annealing occurs at 0 C and the initial characteristics of the cells are restored by annealing at 200 C. The rate of annealing does not appear to follow a simple nth order reaction rate model. Calculations of the short-circuit current density using quantum efficiency measurements and the standard AM1.5 global spectrum compare favorably with measured values. It is proposed that the degradation in J sub sc with irradiation is due to carrier recombination through the fraction of D (o) states bounded by the quasi-Fermi energies. The time dependence of the rate of annealing of J sub sc does appear to be consistent with the interpretation that there is a thermally activated dispersive transport mechanism which leads to the passivation of the irradiation induced defects.

AMINO ACIDURIA IN PRIMATES FOLLOWING IRRADIATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunter, C.G.

The daily urine amino N excretion of 4 monkeys was followed before and after whole body irradiation with doses in the lower lethal range. In 2 non- survivors, there was little change in the daily quantity excreted until terminally. In 2 survivors given the same food intakes as in the irradiated study and sham irradiated, the daily urine amino N excretion during the first week differed but slightly from the values after irradiation, but in the second week more amino N was excreted after irradiation in one animal and less in the other. It would appear that amino aciduria inmore » primates irradiated with doses in the lower lethal range is inseparable from the natural response of the over-all protein metabolism associated with any injury. (auth)« less

Implication of global environmental changes on chemical toxicity-effect of water temperature, pH, and ultraviolet B irradiation on acute toxicity of several pharmaceuticals in Daphnia magna.

PubMed

Kim, Jungkon; Park, Jeongim; Kim, Pan-Gyi; Lee, Chulwoo; Choi, Kyunghee; Choi, Kyungho

2010-04-01

Global environmental change poses emerging environmental health challenges throughout the world. One of such threats could be found in chemical safety in aquatic ecosystem. In the present study, we evaluated the effect of several environmental factors, such as water pH, temperature and ultraviolet light on the toxicity of pharmaceutical compounds in water, using freshwater invertebrate Daphnia magna. Seven pharmaceuticals including ibuprofen, acetaminophen, lincomycin, ciprofloxacin, enrofloxacin, chlortetracycline and sulfathiazole were chosen as test compounds based on their frequent detection in water. The experimental conditions of environmental parameters were selected within the ranges that could be encountered in temperate environment, i.e., water temperature (15, 21, and 25 degrees C), pH (7.4, 8.3, and 9.2), and UV-B light intensity (continuous irradiation of 15.0 microW/cm(2)). For acetaminophen, enrofloxacin and sulfathiazole, decrease in water pH generally led to increase of acute lethal toxicity, which could be explained by the unionized fraction of pharmaceuticals. Increase of water temperature enhanced the acute toxicity of the acetaminophen, enrofloxacin and chlortetracycline, potentially due to alteration in toxicokinetics of chemicals as well as impact on physiological mechanisms of the test organism. The presence of UV-B light significantly increased the toxicity of sulfathiazole, which could be explained by photo-modification of this chemical that lead to oxidative stress. Under the UV light, however, acute toxicity of enrofloxacin decreased, which might be due to photo-degradation. Since changing environmental conditions could affect exposure and concentration-response profile of environmental contaminants, such conditions should be identified and evaluated in order to better manage ecosystem health under changing global environment.

Rapid detection of irradiated frozen hamburgers

NASA Astrophysics Data System (ADS)

Delincée, Henry

2002-03-01

DNA comet assay can be employed as a rapid and inexpensive screening test to check whether frozen ground beef patties (hamburgers) have been irradiated as a means to increase their safety by eliminating pathogenic bacteria, e.g. E. coli O157:H7. Such a detection procedure will provide an additional check on compliance with existing regulations, e.g. enforcement of labelling and rules in international trade. Frozen ready prepared hamburgers from the market place were `electron irradiated' with doses of 0, 1.3, 2.7, 4.5 and 7.2kGy covering the range of potential commercial irradiation. DNA fragmentation in the hamburgers was made visible within a few hours using the comet assay, and non-irradiated hamburgers could be easily discerned from the irradiated ones. Even after 9 months of frozen storage, irradiated hamburgers could be identified. Since DNA fragmentation may also occur with other food processes (e.g. temperature abuse), positive screening tests shall be confirmed using a validated method to specifically prove an irradiation treatment, e.g. EN 1784 or EN 1785.

Thermal analysis applied to irradiated propolis

NASA Astrophysics Data System (ADS)

Matsuda, Andrea Harumi; Machado, Luci Brocardo; del Mastro, Nélida Lucia

2002-03-01

Propolis is a resinous hive product, collected by bees. Raw propolis requires a decontamination procedure and irradiation appears as a promising technique for this purpose. The valuable properties of propolis for food and pharmaceutical industries have led to increasing interest in its technological behavior. Thermal analysis is a chemical analysis that gives information about changes on heating of great importance for technological applications. Ground propolis samples were 60Co gamma irradiated with 0 and 10 kGy. Thermogravimetry curves shown a similar multi-stage decomposition pattern for both irradiated and unirradiated samples up to 600°C. Similarly, through differential scanning calorimetry , a coincidence of melting point of irradiated and unirradiated samples was found. The results suggest that the irradiation process do not interfere on the thermal properties of propolis when irradiated up to 10 kGy.

Irradiation Microstructure of Austenitic Steels and Cast Steels Irradiated in the BOR-60 Reactor at 320°C

NASA Astrophysics Data System (ADS)

Yang, Yong; Chen, Yiren; Huang, Yina; Allen, Todd; Rao, Appajosula

Reactor internal components are subjected to neutron irradiation in light water reactors, and with the aging of nuclear power plants around the world, irradiation-induced material degradations are of concern for reactor internals. Irradiation-induced defects resulting from displacement damage are critical for understanding degradation in structural materials. In the present work, microstructural changes due to irradiation in austenitic stainless steels and cast steels were characterized using transmission electron microscopy. The specimens were irradiated in the BOR-60 reactor, a fast breeder reactor, up to 40 dpa at 320°C. The dose rate was approximately 9.4x10-7 dpa/s. Void swelling and irradiation defects were analyzed for these specimens. A high density of faulted loops dominated the irradiated-altered microstructures. Along with previous TEM results, a dose dependence of the defect structure was established at 320°C.

Think the way to measure the Earth Radiation Budget and the Total Solar Irradiance with a small satellites constellation

NASA Astrophysics Data System (ADS)

Meftah, M.; Keckhut, P.; Damé, L.; Bekki, S.; Sarkissian, A.; Hauchecorne, A.

2018-05-01

Within the past decade, satellites constellations have become possible and practical. One of the interest to use a satellites constellation is to measure the true Earth Radiation Imbalance, which is a crucial quantity for testing climate models and for predicting the future course of global warming. This measurement presents a high interest because the 2001-2010 decade has not shown the accelerating pace of global warming that most models predict, despite the fact that the greenhouse-gas radiative forcing continues to rise. All estimates (ocean heat content and top of atmosphere) show that over the past decade the Earth radiation imbalance ranges between 0.5 to 1W-2. Up to now, the Earth radiation imbalance has not been measured directly. The only way to measure the imbalance with sufficient accuracy is to measure both the incoming solar radiations (total solar irradiance) and the outgoing terrestrial radiations (top of atmosphere outgoing longwave radiations and shortwave radiations) onboard the same satellite, and ideally, with the same instrument. The incoming solar radiations and the outgoing terrestrial radiations are of nearly equal magnitude of the order of 340.5W-2. The objective is to measure these quantities over time by using differential Sun-Earth measurements (to counter calibration errors) with an accuracy better than 0.05Wm-2 at 1σ. It is also necessary to have redundant instruments to track aging in space in order to measure during a decade and to measure the global diurnal cycle with a dozen satellites. Solar irradiance and Earth Radiation Budget (SERB) is a potential first in orbit demonstration satellite. The SERB nano-satellite aims to measure on the same platform the different components of the Earth radiation budget and the total solar irradiance. Instrumental payloads (solar radiometer and Earth radiometers) can acquire the technical maturity for the future large missions (constellation that insure global measurement cover) by flying in a

Proton irradiation study of GFR candidate ceramics

NASA Astrophysics Data System (ADS)

Gan, Jian; Yang, Yong; Dickson, Clayton; Allen, Todd

2009-06-01

This work investigated the microstructural response of SiC, ZrC and ZrN irradiated with 2.6 MeV protons at 800 °C to a fluence of 2.75 × 10 19 protons/cm 2, corresponding to 0.71-1.8 displacement per atom (dpa), depending on the material. The change of lattice constant evaluated using HOLZ patterns is not observed. In comparison to Kr ion irradiation at 800 °C to 10 dpa from the previous studies, the proton irradiated ZrC and ZrN at 1.8 dpa show less irradiation damage to the lattice structure. The proton irradiated ZrC exhibits faulted loops which are not observed in the Kr ion irradiated sample. ZrN shows the least microstructural change from proton irradiation. The microstructure of 6H-SiC irradiated to 0.71 dpa consists of black dot defects at high density.

Irradiation induced kyphosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Riseborough, E.J.

1977-10-01

Eighty-one patients with Wilms tumor treated by irradiation and chemotherapy were studied. Despite the fact that multiple portals for irradiation were used, each crossing the midline, the amount of irradiation delivered to different parts of the vertebral body varied and it was this variation in delivered dose which produced axial skeletal deformities in 70% of the patients. Of the 57 patients with these deformities, 32 had scoliosis, 22 kyphoscoliosis and 3 patients pure kyphosis; 12 patients had a kyphotic deformity of over 25 degrees, 7 patients requiring surgical correction. A high incidence of pseudarthrosis following posterior fusion has led tomore » the preference of a 2-stage procedure, anterior interbody fusion followed by a posterior fusion with Harrington rods after 2 weeks of correction in halo femoral traction.« less

Embrittlement behavior of neutron irradiated RAFM steels

NASA Astrophysics Data System (ADS)

Gaganidze, E.; Schneider, H.-C.; Dafferner, B.; Aktaa, J.

2007-08-01

The effects of neutron irradiation on the embrittlement behavior of reduced activation ferritic/martensitic (RAFM) steel EUROFER97 for different heat treatment conditions have been investigated. The irradiation to 16.3 dpa at different irradiation temperatures (250-450 °C) was carried out in the Petten High Flux Reactor in the framework of the HFR Phase-IIb (SPICE) irradiation project. Several reference RAFM steels (F82H-mod, OPTIFER-Ia, GA3X) and MANET-I were also irradiated at selected temperatures. The embrittlement behavior and hardening were investigated by instrumented Charpy-V tests with subsize specimens. The neutron irradiation induced embrittlement and hardening of as-delivered EUROFER97 are comparable to those of investigated reference steels, being mostly pronounced for 250 °C and 300 °C irradiation temperatures. Heat treatment of EUROFER97 at higher austenization temperature substantially improves the embrittlement behavior at irradiation temperatures of 250 °C and 350 °C.

Design of YCF-1 mobile γ irradiator

NASA Astrophysics Data System (ADS)

Hehu, Zhang; Chuanzhen, Wang

1993-07-01

YCF-1 Mobile irradiator is designed by BINE of China. It has been put into running in YanJi city of Jilin province. It is able to be moved to border and distance places and area lumped and spreading out of agricultural products to service. It can play a important role in demonstration and extending irradiation technology in food irradiation, disinfestation, sterilization and quarantine, etc. This paper describes the features and design considerations of mobile irradiator. This irradiator adopted Cesium-137 source. The design capacity of loading source is 9.25PBq (250kCi), A half-time of Cs- 137 is 30.2 years long, exchanging source is not needed utilization rate of energy is higher, and the shielding is thinner, The Weight is lighter, The dose rate on the surface of it is 0.0025mSv/h in accordance with national standard. The internal size of irradiation room is 1800×1800×900mm (L×W×H), The sheilding of irradiation room is a steel shell filled with lead. The thickness of lead is 18cm. The irradiator is installed on a special flat truck. The size of the truck is 7000×3400×4200mm (L×W×H). The weight of irradiator is more than 80 150kw. The main components and parts of irradiator are: source, source racks and hoist, irradiation chamber, storage source chamber, the product's transport system, dose monitoring system, ventilation system and safety interlock system, etc.

Plasmodium falciparum: attenuation by irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waki, S.; Yonome, I.; Suzuki, M.

The effect of irradiation on the in vitro growth of Plasmodium falciparum was investigated. The cultured malarial parasites at selected stages of development were exposed to gamma rays and the sensitivity of each stage was determined. The stages most sensitive to irradiation were the ring forms and the early trophozoites; late trophozoites were relatively insensitive. The greatest resistance was shown when parasites were irradiated at a time of transition from the late trophozoite and schizont stages to young ring forms. The characteristics of radiosensitive variation in the parasite cycle resembled that of mammalian cells. Growth curves of parasites exposed tomore » doses of irradiation upto 150 gray had the same slope as nonirradiated controls but parasites which were exposed to 200 gray exhibited a growth curve which was less steep than that for parasites in other groups. Less than 10 organisms survived from the 10(6) parasites exposed to this high dose of irradiation; the possibility exists of obtaining radiation-attenuated P. falciparum.« less

Mechanical properties of irradiated beryllium

NASA Astrophysics Data System (ADS)

Beeston, J. M.; Longhurst, G. R.; Wallace, R. S.; Abeln, S. P.

1992-10-01

Beryllium is planned for use as a neutron multiplier in the tritium breeding blanket of the International Thermonuclear Experimental Reactor (ITER). After fabricating samples of beryllium at densities varying from 80 to 100% of the theoretical density, we conducted a series of experiments to measure the effect of neutron irradiation on mechanical properties, especially strength and ductility. Samples were irradiated in the Advanced Test Reactor (ATR) to a neutron fluence of 2.6 × 10 25 n/m 2 ( E > 1 MeV) at an irradiation temperature of 75°C. These samples were subsequently compression-tested at room temperature, and the results were compared with similar tests on unirradiated specimens. We found that the irradiation increased the strength by approximately four times and reduced the ductility to approximately one fourth. Failure was generally ductile, but the 80% dense irradiated samples failed in brittle fracture with significant generation of fine particles and release of small quantities of tritium.

Irradiation preservation of seafood: Literature review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Molton, P.M.

1987-10-01

The application of gamma-irradiation for extending the shelf life of seafood has been of interest for many years. This report reviews a number of studies on seafood irradiation conducted over the past several years. Topics covered include seafood irradiation techniques and dosages, species applicability and differences, the effects of packaging on seafood preservation, and changes in organoleptic acceptability as a result of irradiation. Particular attention is given to radiation effects (likely and unlikely) of concern to the public. These include the potential for generation of toxic chemical products, botulinum toxin production, and other health concerns. No scientifically defensible evidence ofmore » any kind was found for any harmful effect of irradiation of seafoods at the doses being considered (less than 300 krad), and all indications are that irradiation is an acceptable and needed additional tool for seafood preservation. 49 refs., 14 figs., 14 tabs.« less

Progress of food irradiation in the United States

NASA Astrophysics Data System (ADS)

Derr, D. D.; Engeljohn, D. L.; Griffin, R. L.

1995-02-01

Irradiated foods have not yet made a significant impact in the United States marketplace. What progress has occurred to facilitate their commercialization? Irradiated produce has been sold in small quantities since 1992 and irradiated poultry was introduced in the marketplace in 1993. Federal inspection of irradiated commodities has settled into a regular routine. What must occur to further expand irradiated foods in the marketplace? Petitions to permit irradiation of red meats and seafood are being considered by the Food and Drug Administration (FDA) and a petition to permit the irradiation of shell eggs is being prepared for submission to FDA. In addition, the U.S. Department of Agriculture (USDA) has accelerated efforts to develop the policies and regulatory structure needed to facilitate the approval of new irradiation treatments for imported plant products regulated by quarantine. When will greater commercialization occur? More positive coverage to food irradiation in recent months by both the trade and popular press indicates a change in attitude towards irradiated foods by both consumers and the food industry. Finally, actual consumer response to available irradiated foods casts a favorable light on the potential for increased marketing of value-added irradiated foods.

Comminuting irradiated ferritic steel

DOEpatents

Bauer, Roger E.; Straalsund, Jerry L.; Chin, Bryan A.

1985-01-01

Disclosed is a method of comminuting irradiated ferritic steel by placing the steel in a solution of a compound selected from the group consisting of sulfamic acid, bisulfate, and mixtures thereof. The ferritic steel is used as cladding on nuclear fuel rods or other irradiated components.

Irradiation-induced effects of proton irradiation on zirconium carbides with different stoichiometries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Y. Huang; B.R. Maier; T.R. Allen

2014-10-01

Zirconium carbide (ZrC) is being considered for utilization in deep burn TRISO fuel particles for hightemperature, gas-cooled reactors. Zirconium carbide has a cubic B1 type crystal structure along with a very high melting point (3420 ?C), exceptional hardness and good thermal and electrical conductivities. Understanding the ZrC irradiation response is crucial for establishing ZrC as an alternative component in TRISO fuel. Until now, very few studies on irradiation effects on ZrC have been released and fundamental aspects of defect evolution and kinetics are not well understood although some atomistic simulations and phenomenological studies have been performed. This work was carriedmore » out to understand the damage evolution in float-zone refined ZrC with different stoichiometries. Proton irradiations at 800 ?C up to doses of 3 dpa were performed on ZrCx (where x ranges from 0.9 to 1.2) to investigate the damage evolution. The irradiation-induced defects, such as density of dislocation loops, at different stoichiometries and doses which were characterized by transmission electron microscopy (TEM) is presented and discussed.« less

On the causal structure between CO2 and global temperature

PubMed Central

Stips, Adolf; Macias, Diego; Coughlan, Clare; Garcia-Gorriz, Elisa; Liang, X. San

2016-01-01

We use a newly developed technique that is based on the information flow concept to investigate the causal structure between the global radiative forcing and the annual global mean surface temperature anomalies (GMTA) since 1850. Our study unambiguously shows one-way causality between the total Greenhouse Gases and GMTA. Specifically, it is confirmed that the former, especially CO2, are the main causal drivers of the recent warming. A significant but smaller information flow comes from aerosol direct and indirect forcing, and on short time periods, volcanic forcings. In contrast the causality contribution from natural forcings (solar irradiance and volcanic forcing) to the long term trend is not significant. The spatial explicit analysis reveals that the anthropogenic forcing fingerprint is significantly regionally varying in both hemispheres. On paleoclimate time scales, however, the cause-effect direction is reversed: temperature changes cause subsequent CO2/CH4 changes. PMID:26900086

Void swelling and irradiation creep in austenitic and martensitic stainless steels under cyclic irradiation

NASA Astrophysics Data System (ADS)

Zhiyong, Zhu; Jung, Peter; Klein, Horst

1993-07-01

A high purity austenitic FeCrNiMo alloy and DIN 1.4914 martensitic stainless steel were irradiated with 6.2 MeV protons. The pulsed operation of a tokamak fusion reactor was simulated by simultaneous cycling of beam, temperature and stress similar to that anticipated in the NET (Next European Torus) design. Void swelling and irradiation creep of the FeCrNiMo alloy under cyclic and stationary conditions were identical within the experimental error. The martensitic steel showed no swelling at the present low doses (~0.2 dpa). The plastic deformation under continuous and cyclic irradiation was essentially determined by thermal creep. During irradiation the electrical resistivity of FeCrNiMo slightly increased, probably due to swelling, while that of DIN 1.4914 linearly decreased, probably due to segregation effects.

Global / globalizing cities.

PubMed

Yeoh, B S

1999-01-01

Along with the rise in research on globalization, the concept of globalization has become a subject to a more critical scrutiny. While majority agree that it represents a serious challenge to the state-centrist assumptions of most previous social science, doubts about its newness, inevitability and epoch-making qualities are also being raised. Others argue that the globalization literature neglects issues of social regulation by the nation-state, while some critics view it as a discourse drawn upon to legitimize particular political and economic agendas. Debates focus on metropolitan manifestations and impacts. Moving from this background, the paper presents three sociospatial urban configurations that have emerged in the literature. Alongside attempts at identifying globalizing cities and transnational urban networks as new theoretical subjects, another significant vein in the literature focuses on the complex forces of globalization and the production of new urban spaces in these cities. In addition, economic conceptions of globalization is now being pushed beyond adding sociocultural or sociopolitical dimensions and argue instead for the need to theorize globalization as a discursive formation. The global city as a discursive category conjures up imaginary concepts of high modernity, megadevelopment, 21st century urbanity. However, it is noted that the way forward is to focus on the distinctive ways in which urban actors engage in specific processes of economic and social reflexivity. There exists an urgent task for theorizations of the global city, which weave together historical, economic, cultural, sociopolitical and discursive dimensions.

Irradiation doses on thyroid gland during the postoperative irradiation for breast cancer.

PubMed

Akın, Mustafa; Ergen, Arzu; Unal, Aysegul; Bese, Nuran

2014-01-01

Thyroid gland is one of the radiosensitive endocrine organs in the body. It has been shown that direct irradiation of thyroid with total doses of 26 to 30 Gy can lead to functional abnormalities. In this study, irradiation doses on thyroid gland of the patients who received postoperative chest-wall/breast and regional nodal irradiation were assessed. Retrospective analyses of treatment plans from 122 breast cancer patients who were treated with 3D conformal radiotherapy (3D CRT) planning was performed. All patients received irradiation to supraclavicular/level III lymph nodes in addition to chest-wall/breast. A total dose of 46 Gy was delivered in 25 days to supraclavicular/level III lymph node region while a total dose of 50 Gy was delivered to whole breast/chest-wall. Thyroid gland was contoured on 2-5 mm thickness of computed tomography scans. Absolute thyroid volume, mean thyroid doses were calculated. The mean thyroid volume of all patients was 16.7 cc (min: 1.9 cc, max: 41.6 cc). The mean irradiation dose on was 22.5 Gy (0.32 Gy-46.5 Gy). The level of dose was higher than 26 Gy in 44% of the patients. In majority of the node-positive breast cancer patients treated with 3D CRT, the thyroid gland was exposed to considerable doses. On the other hand, for 44% of the patients are at risk for developing thyroid function abnormalities which should be considered during the routine follow-up.

The present situation of the irradiation application industry and irradiation facilities in Japan

NASA Astrophysics Data System (ADS)

Mizusawa, K.; Baba, T.

2003-08-01

The irradiation application industry and irradiation facilities in Japan have been making slow but steady progress for the past 2-3 years. Beside conventional applications, new ones such as carbon fibers and membrane filters have come into the market. There are a lot of new applications about to emerge. PE tubing, already is in the European market, is being evaluated by end users in Japan. Cleaning of dioxin in exhaust gas was successfully tested at a pilot plant. Cross-linked PTFE and polyamide are waiting customers' evaluations as an engineering plastic. Surface cross-linking of artificial polycarbonate teeth has yielded remarkable experimental results. Cross-linking of polycaprolactone will be useful for biodegradable products. Being aware of the future growth of irradiation industry, contract service providers opened new facilities or increased their capability. Beside in-house facilities, there are now three Co-60 facilities and nine EB facilities available for contract irradiation in Japan.

DNA repair factor XPC is modified by SUMO-1 and ubiquitin following UV irradiation

PubMed Central

Wang, Qi-En; Zhu, Qianzheng; Wani, Gulzar; El-Mahdy, Mohamed A.; Li, Jinyou; Wani, Altaf A.

2005-01-01

Nucleotide excision repair (NER) is the major DNA repair process that removes diverse DNA lesions including UV-induced photoproducts. There are more than 20 proteins involved in NER. Among them, XPC is thought to be one of the first proteins to recognize DNA damage during global genomic repair (GGR), a sub-pathway of NER. In order to study the mechanism through which XPC participates in GGR, we investigated the possible modifications of XPC protein upon UV irradiation in mammalian cells. Western blot analysis of cell lysates from UV-irradiated normal human fibroblast, prepared by direct boiling in an SDS lysis buffer, showed several anti-XPC antibody-reactive bands with molecular weight higher than the original XPC protein. The reciprocal immunoprecipitation and siRNA transfection analysis demonstrated that XPC protein is modified by SUMO-1 and ubiquitin. By using several NER-deficient cell lines, we found that DDB2 and XPA are required for UV-induced XPC modifications. Interestingly, both the inactivation of ubiquitylation and the treatment of proteasome inhibitors quantitatively inhibited the UV-induced XPC modifications. Furthermore, XPC protein is degraded significantly following UV irradiation in XP-A cells in which sumoylation of XPC does not occur. Taken together, we conclude that XPC protein is modified by SUMO-1 and ubiquitin following UV irradiation and these modifications require the functions of DDB2 and XPA, as well as the ubiquitin–proteasome system. Our results also suggest that at least one function of UV-induced XPC sumoylation is related to the stabilization of XPC protein. PMID:16030353

Calculating Irradiance For Photosynthesis In The Ocean

NASA Technical Reports Server (NTRS)

Collins, Donald J.; Davis, Curtiss O.; Booth, C. Rockwell; Kiefer, Dale A.; Stallings, Casson

1990-01-01

Mathematical model predicts available and usable irradiances. Yields estimates of irradiance available for photosynthesis (Epar) and irradiance usable for photosynthesis (Epur) as functions of depth in ocean. Describes Epur and Epar in terms of spectral parameters measured remotely (from satellites or airplanes). These irradiances useful in studies of photosynthetic productivity of phytoplankton in euphotic layer.

Global conditions in the solar corona from 2010 to 2017

PubMed Central

Morgan, Huw; Taroyan, Youra

2017-01-01

Through reduction of a huge data set spanning 2010–2017, we compare mean global changes in temperature, emission measure (EM), and underlying photospheric magnetic field of the solar corona over most of the last activity cycle. The quiet coronal mean temperature rises from 1.4 to 1.8 MK, whereas EM increases by almost a factor of 50% from solar minimum to maximum. An increased high-temperature component near 3 MK at solar maximum drives the increase in quiet coronal mean temperature, whereas the bulk of the plasma remains near 1.6 MK throughout the cycle. The mean, spatially smoothed magnitude of the quiet Sun magnetic field rises from 1.6 G in 2011 to peak at 2.0 G in 2015. Active region conditions are highly variable, but their mean remains approximately constant over the cycle, although there is a consistent decrease in active region high-temperature emission (near 3 MK) between the peak of solar maximum and present. Active region mean temperature, EM, and magnetic field magnitude are highly correlated. Correlation between sunspot/active region area and quiet coronal conditions shows the important influence of decaying sunspots in driving global changes, although we find no appreciable delay between changes in active region area and quiet Sun magnetic field strength. The hot coronal contribution to extreme ultraviolet (EUV) irradiance is dominated by the quiet corona throughout most of the cycle, whereas the high variability is driven by active regions. Solar EUV irradiance cannot be predicted accurately by sunspot index alone, highlighting the need for continued measurements. PMID:28740861

Irradiation effects on hydrases for biomedical applications

NASA Astrophysics Data System (ADS)

Furuta, Masakazu; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio

2000-03-01

To apply an irradiation technique to sterilize "Hybrid" biomedical materials including enzymes, we selected papain, a well-characterized plant endopeptidase as a model to examine durability of enzyme activity under the practical irradiation condition in which limited data were available for irradiation inactivation of enzymes. Dry powder and frozen aqueous solution of papain showed significant durability against 60Co-gamma irradiation suggesting that, the commercial irradiation sterilizing method is applicable without modification. Although irradiation of unfrozen aqueous papain solution showed an unusual change of the enzymatic activity with the increasing doses, and was totally inactivated at 15 kGy, we managed to keep the residual activity more than 50% of initial activity after 30-kGy irradiation, taking such optimum conditions as increasing enzyme concentration from 10 to 100 mg/ml and purging with N 2 gas to suppress the formation of free radicals.

Particular applications of food irradiation fresh produce

NASA Astrophysics Data System (ADS)

Prakash, Anuradha

2016-12-01

On fresh fruits and vegetables, irradiation at low and medium dose levels can effectively reduce microbial counts which can enhance safety, inhibit sprouting to extend shelf-life, and eliminate or sterilize insect pests which can serve to facilitate trade between countries. At the dose levels used for these purposes, the impact on quality is negligible. Despite the fact that regulations in many countries allow the use of irradiation for fresh produce, the technology remains under-utilized, even in the light of an increase in produce related disease outbreaks and the economic benefits of extended shelf life and reduced food waste. Putative concerns about consumer acceptance particularly for produce that is labeled as irradiated have deterred many companies from using irradiation and retailers to carry irradiated produce. This section highlights the commercial use of irradiation for fresh produce, other than phytosanitary irradiation which is covered in supplementary sections.

Uncertainty in regional and zonal monthly mean downward surface irradiances from Edition 4.0 CERES Energy Balanced and Filled (EBAF) data product

NASA Astrophysics Data System (ADS)

Kato, S.; Rutan, D. A.; Rose, F. G.; Loeb, N. G.

2017-12-01

The surface of the Earth receives solar radiation (shortwave) and emission from the atmosphere (longwave). At a global and annual mean approximately 12% of solar radiation incident on the surface is reflected and the rest is absorbed by the surface. The surface emits radiation proportional to the forth power of the temperature. Although the uncertainty in global and annual mean surface irradiances is estimated in earlier studies (Zhang et al. 1995, 2004; L'Ecuyer et al. 2008; Stephens et al. 2012; Kato et al. 2012), only a few studies estimated the uncertainty in computed surface irradiances at smaller spatial and temporal scales (Zhang et al. 1995, 2004; Kato et al. 2012). We use surface observations at 46 buoys and 36 land sites and newly released the Edition 4.0 Clouds and the Earth's Radiant Energy System (CERES) Energy Balanced and Filled (EBAF)-surface data product to estimate the uncertainty in regional and zonal monthly mean downward shortwave and longwave surface irradiances. The root-mean-square difference of monthly mean computed and observed irradiances is used for the regional uncertainty. The uncertainty is separated into bias and spatially random components. The random component decreases when irradiances are averaged over a larger area, nearly inversely proportional to the number of surface observation sites. The presentation provides the uncertainty in the regional and zonal monthly mean downward surface irradiances over ocean and land. ReferencesKato, S. and N.G.Loeb, D. A.Rutan, F. G. Rose, S. Sun-Mack,W.F.Miller, and Y. Chen, 2012. Surv. Geophys., 33, 395-412, doi:10.1007/s10712-012-9179-x. L'Ecuyer, T. S., N. B. Wood, T. Haladay, G. L. Stephens, and P. W. Stackhouse Jr., 2008, J. Geophys. Res., 113, D00A15, doi:10.1029/2008JD009951. Stephens, G. L. and Coauthors, 2012, Nat. Geosci., 5, 691-696, doi:10.1038/ngeo1580. Zhang, Y., W. B. Rossow, A. A. Lacis, V. Oinas, and M. I. Mishchenko, 2004, J. Geophys. Res., 109, D19105, doi:10.1029/2003JD

Free radical kinetics on irradiated fennel

NASA Astrophysics Data System (ADS)

Yamaoki, Rumi; Kimura, Shojiro; Ohta, Masatoshi

2008-09-01

Herein, an electron spin resonance study on the behavior of organic radicals in fennel before and after irradiation is reported. The spectrum of irradiated fennel composed of the spectrum component derived from the un-irradiated sample (near g=2.005) and the spectra components derived from carbohydrates. The time decay of intensity spectral components was well explained by first-order kinetics with a variety of rate constants. Especially, the signal at near g=2.02 ascribed to stable cellulose-derivative components is expected to be a good indicator in the identification of irradiated plant samples.

ATF Neutron Irradiation Program Technical Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geringer, J. W.; Katoh, Yutai

The Japan Atomic Energy Agency (JAEA) under the Civil Nuclear Energy Working Group (CNWG) is engaged in a cooperative research effort with the U.S. Department of Energy (DOE) to explore issues related to nuclear energy, including research on accident-tolerant fuels and materials for use in light water reactors. This work develops a draft technical plan for a neutron irradiation program on the candidate accident-tolerant fuel cladding materials and elements using the High Flux Isotope Reactor (HFIR). The research program requires the design of a detailed experiment, development of test vehicles, irradiation of test specimens, possible post-irradiation examination and characterization ofmore » irradiated materials and the shipment of irradiated materials to JAEA in Japan. This report discusses the technical plan of the experimental study.« less

Food irradiation: Standards, regulations and world-wide trade

NASA Astrophysics Data System (ADS)

Roberts, Peter B.

2016-12-01

There is an established framework of international standards for food irradiation covering human health, plant protection, labelling, dose delivery, quality assurance and facility management. Approximately 60 countries permit irradiation of one or more food or food classes. National regulations are briefly reviewed. Decontamination of spices, herbs and condiments remains the single largest application of irradiation. However, in recent years the market for irradiated fresh and processed meat has become firmly established in several countries including China and the USA. At least 10 countries have recently established bi-lateral agreements for trade in irradiated fresh fruits and vegetables using phytosanitary irradiation. Irradiated fresh produce volumes now exceed 20,000 t per year. Rationalization and greater consistency in labelling regulations would be advantageous to the future growth of applications of food irradiation.

Effect of gamma-irradiation on degradation of alginate.

PubMed

Lee, Dong Wook; Choi, Won Seok; Byun, Myung Woo; Park, Hyun Jin; Yu, Yong-Man; Lee, Chong M

2003-07-30

The aqueous solution of alginate was irradiated by 60Co gamma-rays in the dose range of 10-500 kGy. To assess the effect of irradiation on the degradation of alginate, the irradiation-induced changes in the viscosity, molecular weight, color, monomer composition, and sequence were measured. The molecular weight of raw alginate was reduced from 300000 to 25000 when irradiated at 100 kGy. The degradation rate decreased and the chain breaks per molecule increased with increasing irradiation dose. The viscosity of irradiated alginate solution reached a near minimum as low as at 10 kGy. No appreciable color changes were observed in the samples irradiated at up to 100 kGy, but intense browning occurred beyond 200 kGy. The 13C NMR spectra showed that homopolymeric blocks, MM and GG, increased and the M/G ratio decreased with irradiation. Considering both the level of degradation and the color change of alginate, the optimum irradiation dose was found to be 100 kGy.

The Next Spaceflight Solar Irradiance Sensor: TSIS

NASA Astrophysics Data System (ADS)

Kopp, Greg; Pilewskie, Peter; Richard, Erik

2016-05-01

The Total and Spectral Solar Irradiance Sensor (TSIS) will continue measurements of the solar irradiance with improved accuracies and stabilities over extant spaceflight instruments. The two TSIS solar-observing instruments include the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM) for measuring total- and spectral- solar-irradiance, respectively. The former provides the net energy powering the Earth’s climate system while the latter helps attribute where that energy is absorbed by the Earth’s atmosphere and surface. Both spaceflight instruments are assembled and being prepared for integration on the International Space Station. With operations commencing in late 2017, the TSIS is intended to overlap with NASA’s ongoing SOlar Radiation and Climate Experiment (SORCE) mission, which launched in 2003 and contains the first versions of both the TIM and SIM instruments, as well as with the TSI Calibration Transfer Experiment (TCTE), which began total solar irradiance measurements in 2013. We summarize the TSIS’s instrument improvements and intended solar-irradiance measurements.

Analysis of direct solar ultraviolet irradiance measurements in the French Alps. Retrieval of turbidity and ozone column amount.

PubMed

Lenoble, Jacqueline; de la Casinière, Alain; Cabot, Thierry

2004-05-20

Direct ultraviolet spectral solar irradiance is regularly obtained by the difference between global and diffuse irradiances at the French Alpine station of Briançon; the data of years 2001 and 2002 are analyzed in this paper. Comparison with modeled values is used for cloud screening, and an average UV-A aerosol optical depth is used as an index of turbidity; it is found to be around 0.05 for the clear winter days and around 0.2 in summer. Langley plots are used to verify the instrument calibration; they confirm the expected uncertainty smaller than 5%. The ozone total column amount is estimated with an uncertainty between -3 and Dobson units; comparisons with TOMS (Total Ozone Mapping Spectrometer) overpass values shows agreement within the expected uncertainties of both instruments.

Thermoluminscence of irradiated herbs and spices

NASA Astrophysics Data System (ADS)

Mamoon, A.; Abdul-Fattah, A. A.; Abulfaraj, W. H.

1994-07-01

Several types of herbs and spices from the local market were irradiated with different doses of γ radiations. Doses varied from a few kilograys to 10 kilograys. Thermoluminescence of the irradiated samples and their controls was investigated. For the same type of herb or spice glow curves of different magnitudes, corresponding somewhat to the doses given, were obtained from the irradiated samples. Most control samples gave little or insignificant glow. Glow curves from different herbs and spices irradiated with the same doses were not similar in the strength of the glow signal given. Samples of the black pepper obtained from different packages sometimes give glow curves of very different intensities. Samples from irradiated black pepper were found to show little fading of their glow curves even at 9 months postirradiation. All irradiations were done under the same experimental conditions and at a dose rate of approximately 1 kGy h-1. The glow curves were obtained using a heating rate of about 9°C s-1 and a constant nitrogen flow rate.

The LASP Interactive Solar IRradiance Datacenter (LISIRD)

NASA Astrophysics Data System (ADS)

Pankratz, C. K.; Lindholm, D. M.; Snow, M.; Knapp, B.; Woodraska, D.; Templeman, B.; Woods, T. N.; Eparvier, F. G.; Fontenla, J.; Harder, J.; McClintock, W. E.

2007-12-01

The Laboratory for Atmospheric and Space Physics (LASP) has been making space-based measurements of solar irradiance for many decades, and thus has established an extensive catalog of past and ongoing space- based solar irradiance measurements. In order to maximize the accessibility and usability of solar irradiance data and information from multiple missions, LASP is developing the LASP Interactive Solar IRradiance Datacenter (LISIRD) to better serve the needs of researchers, educators, and the general public. This data center is providing interactive and direct access to a comprehensive set of solar spectral irradiance measurements from the soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as state-of-the-art measurements of Total Solar Irradiance (TSI). LASP researchers are also responsible for an extensive set of solar irradiance models and historical solar irradiance reconstructions, which will also be accessible via this data center over time. LISIRD currently provides access to solar irradiance data sets from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments, spanning 1981 to the present, as well as a Lyman Alpha composite that is available from 1947 to the present. LISIRD also provides data products of interest to the space weather community, whose needs demand high time cadence and near real-time data delivery. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD's various interfaces.

Does gamma irradiation affect physicochemical properties of honey?

PubMed

Hussein, S Z; Yusoff, K M; Makpol, S; Mohd Yusof, Y A

2014-01-01

Honey is a supersaturated solution of sugars, enriched with proteins, minerals, vitamins, organic acids and polyphenols. Gamma irradiation is a physical technique of food preservation which protects the honey from insects' and microbial contamination during storage. We investigated the effect of gamma irradiation on physicochemical properties in two types of Malaysian honey, Gelam and Nenas. Both honeys were irradiated at the dose 25 kGy in a cobalt-60 irradiator. The physicochemical properties pH, moisture, acidity, color, and sugar content as well as vitamins C and E, hydroxymethylfurfural (HMF) and mineral contents, for the irradiated and non-irradiated honeys were assessed. The results revealed that pH, acidity, minerals and sugar contents in both types of honey were not affected significantly by gamma irradiation, while moisture, vitamin E contents and HMF level decreased significantly with gamma irradiation. However, significant increased in color intensity and vitamin C were observed after gamma irradiation for both types of honey. In summary, gamma irradiation treatment of honey (in the dose mentioned above) did not cause significant changes in the physicochemical and mineral contents, except for significant alterations in color intensity, moisture, vitamins (C and E), and HMF contents.

Clear-Sky Longwave Irradiance at the Earth's Surface--Evaluation of Climate Models.

NASA Astrophysics Data System (ADS)

Garratt, J. R.

2001-04-01

An evaluation of the clear-sky longwave irradiance at the earth's surface (LI) simulated in climate models and in satellite-based global datasets is presented. Algorithm-based estimates of LI, derived from global observations of column water vapor and surface (or screen air) temperature, serve as proxy `observations.' All datasets capture the broad zonal variation and seasonal behavior in LI, mainly because the behavior in column water vapor and temperature is reproduced well. Over oceans, the dependence of annual and monthly mean irradiance upon sea surface temperature (SST) closely resembles the observed behavior of column water with SST. In particular, the observed hemispheric difference in the summer minus winter column water dependence on SST is found in all models, though with varying seasonal amplitudes. The analogous behavior in the summer minus winter LI is seen in all datasets. Over land, all models have a more highly scattered dependence of LI upon surface temperature compared with the situation over the oceans. This is related to a much weaker dependence of model column water on the screen-air temperature at both monthly and annual timescales, as observed. The ability of climate models to simulate realistic LI fields depends as much on the quality of model water vapor and temperature fields as on the quality of the longwave radiation codes. In a comparison of models with observations, root-mean-square gridpoint differences in mean monthly column water and temperature are 4-6 mm (5-8 mm) and 0.5-2 K (3-4 K), respectively, over large regions of ocean (land), consistent with the intermodel differences in LI of 5-13 W m2 (15-28 W m2).

AGR-1 Post Irradiation Examination Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demkowicz, Paul Andrew

The post-irradiation examination (PIE) of the Advanced Gas Reactor (AGR)-1 experiment was a multi-year, collaborative effort between Idaho National Laboratory (INL) and Oak Ridge National Laboratory (ORNL) to study the performance of UCO (uranium carbide, uranium oxide) tristructural isotropic (TRISO) coated particle fuel fabricated in the U.S. and irradiated at the Advanced Test Reactor at INL to a peak burnup of 19.6% fissions per initial metal atom. This work involved a broad array of experiments and analyses to evaluate the level of fission product retention by the fuel particles and compacts (both during irradiation and during post-irradiation heating tests tomore » simulate reactor accident conditions), investigate the kernel and coating layer morphology evolution and the causes of coating failure, and explore the migration of fission products through the coating layers. The results have generally confirmed the excellent performance of the AGR-1 fuel, first indicated during the irradiation by the observation of zero TRISO coated particle failures out of 298,000 particles in the experiment. Overall release of fission products was determined by PIE to have been relatively low during the irradiation. A significant finding was the extremely low levels of cesium released through intact coatings. This was true both during the irradiation and during post-irradiation heating tests to temperatures as high as 1800°C. Post-irradiation safety test fuel performance was generally excellent. Silver release from the particles and compacts during irradiation was often very high. Extensive microanalysis of fuel particles was performed after irradiation and after high-temperature safety testing. The results of particle microanalysis indicate that the UCO fuel is effective at controlling the oxygen partial pressure within the particle and limiting kernel migration. Post-irradiation examination has provided the final body of data that speaks to the quality of the AGR-1 fuel

Rheological changes in irradiated chicken eggs

NASA Astrophysics Data System (ADS)

Ferreira, Lúcia F. S.; Del Mastro, Nélida L.

1998-06-01

Pathogenic bacteria may cause foodborne illnesses. Humans may introduce pathogens into foods during production, processing, distribution and or preparation. Some of these microorganisms are able to survive conventional preservation treatments. Heat pasteurization, which is a well established and satisfactory means of decontamination/disinfection of liquid foods, cannot efficiently achieve a similar objective for solid foods. Extensive work carried out worldwide has shown that irradiation is efficient in eradicating foodborne pathogens like Salmonella spp. that can contaminate poultry products. In this work Co-60 gamma irradiation was applied to samples of industrial powder white, yolk and whole egg at doses between 0 and 25 kGy. Samples were rehydrated and the viscosity measured in a Brookfield viscosimeter, model DV III at 5, 15 and 25°C. The rheological behaviour among the various kinds of samples were markedly different. Irradiation with doses up to 5 kGy, known to reduced bacterial contamination to non-detectable levels, showed almost no variation of viscosity of irradiated egg white samples. On the other hand, whole or yolk egg samples showed some changes in rheological properties depending on the dose level, showing the predominance of whether polimerization or degradation as a result of the irradiation. Additionally, irradiation of yolk egg powder reduced yolk color as a function of the irradiation exposure implemented. The importance of these results are discussed in terms of possible industrial applications.

AGC-2 Specimen Post Irradiation Data Package Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Windes, William Enoch; Swank, W. David; Rohrbaugh, David T.

This report documents results of the post-irradiation examination material property testing of the creep, control, and piggyback specimens from the irradiation creep capsule Advanced Graphite Creep (AGC)-2 are reported. This is the second of a series of six irradiation test trains planned as part of the AGC experiment to fully characterize the neutron irradiation effects and radiation creep behavior of current nuclear graphite grades. The AGC-2 capsule was irradiated in the Idaho National Laboratory Advanced Test Reactor at a nominal temperature of 600°C and to a peak dose of 5 dpa (displacements per atom). One-half of the creep specimens weremore » subjected to mechanical stresses (an applied stress of either 13.8, 17.2, or 20.7 MPa) to induce irradiation creep. All post-irradiation testing and measurement results are reported with the exception of the irradiation mechanical strength testing, which is the last destructive testing stage of the irradiation testing program. Material property tests were conducted on specimens from 15 nuclear graphite grades using a similar loading configuration as the first AGC capsule (AGC-1) to provide easy comparison between the two capsules. However, AGC-2 contained an increased number of specimens (i.e., 487 total specimens irradiated) and replaced specimens of the minor grade 2020 with the newer grade 2114. The data reported include specimen dimensions for both stressed and unstressed specimens to establish the irradiation creep rates, mass and volume data necessary to derive density, elastic constants (Young’s modulus, shear modulus, and Poisson’s ratio) from ultrasonic time-of-flight velocity measurements, Young’s modulus from the fundamental frequency of vibration, electrical resistivity, and thermal diffusivity and thermal expansion data from 100–500°C. No data outliers were determined after all measurements were completed. A brief statistical analysis was performed on the irradiated data and a limited comparison

Identification of irradiated mushrooms (in French)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bugyaki, L.

1973-01-01

From international colloquium: the identification of irradiated foodstuffs; Karlsruhe, Germany (24 Oct 1973). Cuttings from non-irradiated mushrooms, when kept at normal or sub-zero temperatares, produce new hyphae in solld culture media even after slx days, thus proving that they are living. On the other hand, cultures from mushrooms irradiated with 250 krad never show any sign of cellular proliferation. (auth)

Elective ilioingunial lymph node irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henderson, R.H.; Parsons, J.T.; Morgan, L.

1984-06-01

Most radiologists accept that modest doses of irradiation (4500-5000 rad/4 1/2-5 weeks) can control subclinical regional lymph node metastases from squamous cell carcinomas of the head and neck and adenocarcinomas of the breast. There have been few reports concerning elective irradiation of the ilioinguinal region. Between October 1964 and March 1980, 91 patients whose primary cancers placed the ilioinguinal lymph nodes at risk received elective irradiation at the University of Florida. Included are patients with cancers of the vulva, penis, urethra, anus and lower anal canal, and cervix or vaginal cancers that involved the distal one-third of the vagina. Inmore » 81 patients, both inguinal areas were clinically negative; in 10 patients, one inguinal area was positive and the other negative by clinical examination. The single significant complication was a bilateral femoral neck fracture. The inguinal areas of four patients developed mild to moderate fibrosis. One patient with moderate fibrosis had bilateral mild leg edema that was questionably related to irradiation. Complications were dose-related. The advantages and dis-advantages of elective ilioinguinal node irradiation versus elective inguinal lymph node dissection or no elective treatment are discussed.« less

Learning to Plunder: Global Education, Global Inequality and the Global City

ERIC Educational Resources Information Center

Tannock, Stuart

2010-01-01

Most research and policy discussions of education in the global city have focused on the ways in which globalization and the emergence of global or globalizing cities can create social, economic and educational inequality locally, within the global city itself. Global cities, however, are, by definition, powerful places, where the core…

Synthesis of Creatine in X-irradiated Rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nerurkar, M. K.; Sahasrabudhe, M. B.

1960-01-01

BS>Synthesis and excretion of creatine and creatinine in total-body x- irradiated (600 n) rats were investigated. Irradiated rats exhibited a marked creatinuria, whereas creatinine excretion was only slightly increased in comparison to that of non-irradiated control animals. The increased creatine excretion after irradiation was ascribed to accelerated synthesis in the liver and greater release from the muscle. In vitro studies on the synthesis of creatine in liver homogenates revealed that the synthetic activity decreased immediately after irradiation but at later intervals showed a marked rise. The immediate fall in the creatine synthesis was not due to decreased availability of ATPmore » or glutathione. Administration of nicotinamide to animals, to inhibit the new creatine synthesis in the liver. indicated that although the creatine formation in the liver of x-irradiated rats was elevated. it could not account for more than a small fraction of the creatinuria observed. Most of the urinary creatine originated from the muscle, probably because of the impaired reconversion of creatine to phosphocreatine. Since the muscle ATP-creatine transphosphorylase activity was not affected by irradiation, it is suggested that the mobilization of muscle creatine to cause creatinuria is probably due to the diminution of glycolysis in the muscle of irradiated animals.« less

Food irradiation: Technology transfer to developing countries

NASA Astrophysics Data System (ADS)

Kunstadt, Peter

This paper discusses Nordion's experiences to-date with the Food Irradiation Project in Thailand (1987-1990). This project will enable the Government of Thailand and the Thai food industry to benefit from established Canadian technology in food irradiation. It includes the design and the construction in Thailand of a multipurpose irradiation facility, similar to the Canadian Irradiation Centre. In addition Canada provides the services, for extended periods of time, of construction and installation management and experts in facility operation, maintenance and training. The Technology Transfer component is a major part of the overall Thai Food Irradiation Project. Its purpose is to familiarize Thai government and industry personnel with Canadian requirements in food regulations and distribution and to conduct market and consumer tests of selected Thai irradiated food products in Canada, once the products have Canadian regulatory approval. On completion of this project, Thailand will have the necessary facility, equipment and training to continue to provide leadership in food irradiation research, as well as scientific and technical support to food industries not only in Thailand by also in the ASEAN region.

Quality of mixed tropical fruit following irradiation treatment

USDA-ARS?s Scientific Manuscript database

Irradiation can be used to control quarantine insect pests of fresh fruits and vegetables. The economic viability of irradiation improves if a diversity of crops can be treated, but the quality of irradiated produce determines market acceptance. Many tropical fruit tolerate irradiation doses less th...

Regional Nodal Irradiation in Early-Stage Breast Cancer.

PubMed

Whelan, Timothy J; Olivotto, Ivo A; Parulekar, Wendy R; Ackerman, Ida; Chua, Boon H; Nabid, Abdenour; Vallis, Katherine A; White, Julia R; Rousseau, Pierre; Fortin, Andre; Pierce, Lori J; Manchul, Lee; Chafe, Susan; Nolan, Maureen C; Craighead, Peter; Bowen, Julie; McCready, David R; Pritchard, Kathleen I; Gelmon, Karen; Murray, Yvonne; Chapman, Judy-Anne W; Chen, Bingshu E; Levine, Mark N

2015-07-23

Most women with breast cancer who undergo breast-conserving surgery receive whole-breast irradiation. We examined whether the addition of regional nodal irradiation to whole-breast irradiation improved outcomes. We randomly assigned women with node-positive or high-risk node-negative breast cancer who were treated with breast-conserving surgery and adjuvant systemic therapy to undergo either whole-breast irradiation plus regional nodal irradiation (including internal mammary, supraclavicular, and axillary lymph nodes) (nodal-irradiation group) or whole-breast irradiation alone (control group). The primary outcome was overall survival. Secondary outcomes were disease-free survival, isolated locoregional disease-free survival, and distant disease-free survival. Between March 2000 and February 2007, a total of 1832 women were assigned to the nodal-irradiation group or the control group (916 women in each group). The median follow-up was 9.5 years. At the 10-year follow-up, there was no significant between-group difference in survival, with a rate of 82.8% in the nodal-irradiation group and 81.8% in the control group (hazard ratio, 0.91; 95% confidence interval [CI], 0.72 to 1.13; P=0.38). The rates of disease-free survival were 82.0% in the nodal-irradiation group and 77.0% in the control group (hazard ratio, 0.76; 95% CI, 0.61 to 0.94; P=0.01). Patients in the nodal-irradiation group had higher rates of grade 2 or greater acute pneumonitis (1.2% vs. 0.2%, P=0.01) and lymphedema (8.4% vs. 4.5%, P=0.001). Among women with node-positive or high-risk node-negative breast cancer, the addition of regional nodal irradiation to whole-breast irradiation did not improve overall survival but reduced the rate of breast-cancer recurrence. (Funded by the Canadian Cancer Society Research Institute and others; MA.20 ClinicalTrials.gov number, NCT00005957.).

Post-irradiation-examination of irradiated fuel outside the hot cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawn E. Janney; Adam B. Robinson; Thomas P. O'Holleran

Because of their high radioactivity, irradiated fuels are commonly examined in a hot cell. However, the Idaho National Laboratory (INL) has recently investigated irradiated U-Mo-Al metallic fuel from the Reduced Enrichment for Research and Test Reactors (RERTR) project using a conventional unshielded scanning electron microscope outside a hot cell. This examination was possible because of a two-step sample-preparation approach in which a small volume of fuel was isolated in a hot cell and shielding was introduced during later stages of sample preparation. The resulting sample contained numerous sample-preparation artifacts but allowed analysis of microstructures from selected areas.

Study of irradiation damage induced by He2+ ion irradiation in Ni62Ta38 metallic glass and W metal

NASA Astrophysics Data System (ADS)

Zhang, Xiaonan; Mei, Xianxiu; Zhang, Qi; Li, Xiaona; Wang, Yingmin; Wang, Younian

2017-09-01

Metallic glasses are considered to possess good resistant against irradiation due to their inherent structural long-range disorder and a lack of grain boundaries. The He2+ with an energy of 300 keV was used to irradiate Ni62Ta38 binary metallic glass to investigate its resistance against the irradiation, and the irradiated behaviour of the metallic glass was compared with that of W metal. The irradiation fluence range over 2.0 × 1017 ions/cm2-1.6 × 1018 ions/cm2. The TEM results show that nanocrystals of μ-NiTa phase and Ni2Ta phase appeared in Ni62Ta38 metallic glass under the irradiation fluence of 1.6 × 1018 ions/cm2. The SEM results show that the surfaces of Ni62Ta38 metallic glasses maintained flat and smooth, whereas a large area of blisters with peeling formed on the surface of W metal at the irradiation fluence of 1.0 × 1018 ions/cm2. It indicates that the critical irradiation fluence of surface breakage of the Ni62Ta38 metallic glass is higher than that of W metal. After the irradiation, stress was generated in the surface layer of W metal, leading to the increase of the hardness of W metal.

Biological Response of Cancer and Normal Cells on Irradiation from Electrons with Energies up to 200 keV.

NASA Astrophysics Data System (ADS)

Prilepskiy, Yuriy

2007-03-01

This paper presents continuation data of the series of experiments with the electron gun of the CEBAF machine at Jefferson Lab (Newport News, VA), which is capable of delivering electrons with energies up to 200 keV. This 1.5 GHz beam permits to generate cellular damage within minutes. We have performed irradiation of cancer and normal cells with different electron energies and currents to investigate cell biological responses. The biological response is measured through proteomics analysis before and after irradiation. The living cells are encased in special air containers allowing proper positioning in vacuum where the electrons are present. The containers receive the irradiation from the mono energetic electrons with energy up to 120 keV, resulting in an irradiation from both electrons and a small number of photons from the original beam passing through the thin container window. This window allows approximately half of the beam to come through. The study will permit to address the physical processes involved in the RBE and LET at a level that supersedes current data listed in the literature. We will discuss the experimental setup and the second stage of data collected with the new more developed system. This research is part of a global program to provide detailed information for the understanding of radiation based cancer treatments.

Microarchitecture of irradiated bone: comparison with healthy bone

NASA Astrophysics Data System (ADS)

Bléry, Pauline; Amouriq, Yves; Guédon, Jeanpierre; Pilet, Paul; Normand, Nicolas; Durand, Nicolas; Espitalier, Florent; Arlicot, Aurore; Malard, Olivier; Weiss, Pierre

2012-03-01

The squamous cell carcinomas of the upper aero-digestive tract represent about ten percent of cancers. External radiation therapy leads to esthetic and functional consequences, and to a decrease of the bone mechanical abilities. For these patients, the oral prosthetic rehabilitation, including possibilities of dental implant placement, is difficult. The effects of radiotherapy on bone microarchitecture parameters are not well known. Thus, the purpose of this study is to assess the effects of external radiation on bone micro architecture in an experimental model of 25 rats using micro CT. 15 rats were irradiated on the hind limbs by a single dose of 20 Grays, and 10 rats were non irradiated. Images of irradiated and healthy bone were compared. Bone microarchitecture parameters (including trabecular thickness, trabecular number, trabecular separation, connectivity density and tissue and bone volume) between irradiated and non-irradiated bones were calculated and compared using a Mann and Whitney test. After 7 and 12 weeks, images of irradiated and healthy bone are different. Differences on the irradiated and the healthy bone populations exhibit a statistical significance. Trabecular number, connectivity density and closed porosity are less important on irradiated bone. Trabecular thickness and separation increase for irradiated bone. These parameters indicate a decrease of irradiated bone properties. Finally, the external irradiation induces changes on the bone micro architecture. This knowledge is of prime importance for better oral prosthetic rehabilitation, including implant placement.

Solar Irradiance Data Products at the LASP Interactive Solar IRradiance Datacenter (LISIRD)

NASA Astrophysics Data System (ADS)

Lindholm, D. M.; Ware DeWolfe, A.; Wilson, A.; Pankratz, C. K.; Snow, M. A.; Woods, T. N.

2011-12-01

The Laboratory for Atmospheric and Space Physics (LASP) has developed the LASP Interactive Solar IRradiance Datacenter (LISIRD, http://lasp.colorado.edu/lisird/) web site to provide access to a comprehensive set of solar irradiance measurements and related datasets. Current data holdings include products from NASA missions SORCE, UARS, SME, and TIMED-SEE. The data provided covers a wavelength range from soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as Total Solar Irradiance (TSI). Other datasets include solar indices, spectral and flare models, solar images, and more. The LISIRD web site features updated plotting, browsing, and download capabilities enabled by dygraphs, JavaScript, and Ajax calls to the LASP Time Series Server (LaTiS). In addition to the web browser interface, most of the LISIRD datasets can be accessed via the LaTiS web service interface that supports the OPeNDAP standard. OPeNDAP clients and other programming APIs are available for making requests that subset, aggregate, or filter data on the server before it is transported to the user. This poster provides an overview of the LISIRD system, summarizes the datasets currently available, and provides details on how to access solar irradiance data products through LISIRD's interfaces.

Update on meat irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olson, D.G.

1997-12-01

The irradiation of meat and poultry in the United States is intended to eliminate pathogenic bacteria from raw product, preferably after packaging to prevent recontamination. Irradiation will also increase the shelf life of raw meat and poultry products approximately two to three times the normal shelf life. Current clearances in the United States are for poultry (fresh or frozen) at doses from 1.5 to 3.0 kGy and for fresh pork at doses from 0.3 to 1.0 kGy. A petition for the clearance of all red meat was submitted to the Food and Drug Administration (FDA) in July 1994. The petitionmore » is for clearances of fresh meat at doses from 1.5 to 4.5 kGy and for frozen meat at {approximately}2.5 to 7.5 kGy. Clearance for red meat is expected before the end of 1997. There are 28 countries that have food irradiation clearances, of which 18 countries have clearances for meat or poultry. However, there are no uniform categories or approved doses for meat and poultry among the countries that could hamper international trade of irradiated meat and poultry.« less

Intracranial meningiomas related to external cranial irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spallone, A.; Gagliardi, F.M.; Vagnozzi, R.

1979-08-01

Three cases are presented of meningiomas following small-dose external cranial irradiation in which several features clearly indicate a causal relationship between radiotherapy and tumor development. The length of the latent period separates meningiomas following high-dose irradiation from those which followed small-dose irradiation. Therefore the oncogenic mechanism seems to act differently in the two groups. This demonstration that multiple meningiomas can occur in patients irradiated for Tinea capitis should enable other similar cases to be recognized.

Neutron irradiation effects on plasma facing materials

NASA Astrophysics Data System (ADS)

Barabash, V.; Federici, G.; Rödig, M.; Snead, L. L.; Wu, C. H.

2000-12-01

This paper reviews the effects of neutron irradiation on thermal and mechanical properties and bulk tritium retention of armour materials (beryllium, tungsten and carbon). For each material, the main properties affected by neutron irradiation are described and the specific tests of neutron irradiated armour materials under thermal shock and disruption conditions are summarized. Based on current knowledge, the expected thermal and structural performance of neutron irradiated armour materials in the ITER plasma facing components are analysed.

In Search of Sun-Climate Connection Using Solar Irradiance Measurements and Climate Records

NASA Technical Reports Server (NTRS)

Kiang, Richard K.; Kyle, H. Lee

2000-01-01

The Earth's temperature has risen approximately 0.5 degree-C in the last 150 years. Because the atmospheric concentration of carbon dioxide has increased nearly 30% since the industrial revolution, a common conjecture, supported by various climate models, is that anthropogenic greenhouse gases have contributed to global warming. Another probable factor for the warming is the natural variation of solar irradiance. Although the variation is as small as 0.1 % it is hypothesized that it contributes to part of the temperature rise. Warmer or cooler ocean temperature at one part of the Globe may manifest as abnormally wet or dry weather patterns some months or years later at another part of the globe. Furthermore, the lower atmosphere can be affected through its coupling with the stratosphere, after the stratospheric ozone absorbs the ultraviolet portion of the solar irradiance. In this paper, we use wavelet transforms based on Morlet wavelet to analyze the time-frequency properties in several datasets, including the Radiation Budget measurements, the long-term total solar irradiance time series, the long-term temperature at two locations for the North and the South Hemisphere. The main solar cycle, approximately 11 years, are identified in the long-term total solar irradiance time series. The wavelet transform of the temperature datasets show annual cycle but not the solar cycle. Some correlation is seen between the length of the solar cycle extracted from the wavelet transform and the North Hemisphere temperature time series. The absence of the 11-year cycle in a time series does not necessarily imply that the geophysical parameter is not affected by the solar cycle; rather it simply reflects the complex nature of the Earth's response to climate forcings.

Irradiation creep of dispersion strengthened copper alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pokrovsky, A.S.; Barabash, V.R.; Fabritsiev, S.A.

1997-04-01

Dispersion strengthened copper alloys are under consideration as reference materials for the ITER plasma facing components. Irradiation creep is one of the parameters which must be assessed because of its importance for the lifetime prediction of these components. In this study the irradiation creep of a dispersion strengthened copper (DS) alloy has been investigated. The alloy selected for evaluation, MAGT-0.2, which contains 0.2 wt.% Al{sub 2}O{sub 3}, is very similar to the GlidCop{trademark} alloy referred to as Al20. Irradiation creep was investigated using HE pressurized tubes. The tubes were machined from rod stock, then stainless steel caps were brazed ontomore » the end of each tube. The creep specimens were pressurized by use of ultra-pure He and the stainless steel caps subsequently sealed by laser welding. These specimens were irradiated in reactor water in the core position of the SM-2 reactors to a fluence level of 4.5-7.1 x 10{sup 21} n/cm{sup 2} (E>0.1 MeV), which corresponds to {approx}3-5 dpa. The irradiation temperature ranged from 60-90{degrees}C, which yielded calculated hoop stresses from 39-117 MPa. A mechanical micrometer system was used to measure the outer diameter of the specimens before and after irradiation, with an accuracy of {+-}0.001 mm. The irradiation creep was calculated based on the change in the diameter. Comparison of pre- and post-irradiation diameter measurements indicates that irradiation induced creep is indeed observed in this alloy at low temperatures, with a creep rate as high as {approx}2 x 10{sup {minus}9}s{sup {minus}1}. These results are compared with available data for irradiation creep for stainless steels, pure copper, and for thermal creep of copper alloys.« less

The irradiation hardening of Ni-Mo-Cr and Ni-W-Cr alloy under Xe26+ ion irradiation

NASA Astrophysics Data System (ADS)

Chen, Huaican; Hai, Yang; Liu, Renduo; Jiang, Li; Ye, Xiang-xi; Li, Jianjian; Xue, Wandong; Wang, Wanxia; Tang, Ming; Yan, Long; Yin, Wen; Zhou, Xingtai

2018-04-01

The irradiation hardening of Ni-Mo-Cr and Ni-W-Cr alloy was investigated. 7 MeV Xe26+ ion irradiation was performed at room temperature and 650 °C with peak damage dose from 0.05 to 10 dpa. With the increase of damage dose, the hardness of Ni-Mo-Cr and Ni-W-Cr alloy increases, and reaches saturation at damage dose ≥1 dpa. Moreover, the damage dose dependence of hardness in both alloys can be described by the Makin and Minter's equation, where the effective critical volume of obstacles can be used to represent irradiation hardening resistance of the alloys. Our results also show that Ni-W-Cr alloy has better irradiation hardening resistance than Ni-Mo-Cr alloy. This is ascribed to the fact that the W, instead of Mo in the alloy, can suppress the formation of defects under ion irradiation.

Irradiation Induced Microstructure Evolution in Nanostructured Materials: A Review

PubMed Central

Liu, Wenbo; Ji, Yanzhou; Tan, Pengkang; Zang, Hang; He, Chaohui; Yun, Di; Zhang, Chi; Yang, Zhigang

2016-01-01

Nanostructured (NS) materials may have different irradiation resistance from their coarse-grained (CG) counterparts. In this review, we focus on the effect of grain boundaries (GBs)/interfaces on irradiation induced microstructure evolution and the irradiation tolerance of NS materials under irradiation. The features of void denuded zones (VDZs) and the unusual behavior of void formation near GBs/interfaces in metals due to the interactions between GBs/interfaces and irradiation-produced point defects are systematically reviewed. Some experimental results and calculation results show that NS materials have enhanced irradiation resistance, due to their extremely small grain sizes and large volume fractions of GBs/interfaces, which could absorb and annihilate the mobile defects produced during irradiation. However, there is also literature reporting reduced irradiation resistance or even amorphization of NS materials at a lower irradiation dose compared with their bulk counterparts, since the GBs are also characterized by excess energy (compared to that of single crystal materials) which could provide a shift in the total free energy that will lead to the amorphization process. The competition of these two effects leads to the different irradiation tolerance of NS materials. The irradiation-induced grain growth is dominated by irradiation temperature, dose, ion flux, character of GBs/interface and nanoprecipitates, although the decrease of grain sizes under irradiation is also observed in some experiments. PMID:28787902

7 CFR 305.9 - Irradiation treatment requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 5 2014-01-01 2014-01-01 false Irradiation treatment requirements. 305.9 Section 305... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.9 Irradiation treatment requirements. Irradiation, carried out in accordance with the provisions of this section, is approved as a...

7 CFR 305.9 - Irradiation treatment requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 5 2011-01-01 2011-01-01 false Irradiation treatment requirements. 305.9 Section 305... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.9 Irradiation treatment requirements. Irradiation, carried out in accordance with the provisions of this section, is approved as a...

7 CFR 305.9 - Irradiation treatment requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 5 2013-01-01 2013-01-01 false Irradiation treatment requirements. 305.9 Section 305... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.9 Irradiation treatment requirements. Irradiation, carried out in accordance with the provisions of this section, is approved as a...

Biological effects of ultraviolet irradiation on bees

DOE Office of Scientific and Technical Information (OSTI.GOV)

Es`kov, E.K.

1995-09-01

The influence of natural solar and artificial ultraviolet irradiation on developing bees was studied. Lethal exposures to irradiation at different stages of development were determined. The influence of irradiation on the variability of the morphometric features of bees was revealed. 5 refs., 1 fig.

Nanoindentation of ion-irradiated reactor pressure vessel steels - model-based interpretation and comparison with neutron irradiation

NASA Astrophysics Data System (ADS)

Röder, F.; Heintze, C.; Pecko, S.; Akhmadaliev, S.; Bergner, F.; Ulbricht, A.; Altstadt, E.

2018-04-01

Ion-irradiation-induced hardening is investigated on six selected reactor pressure vessel (RPV) steels. The steels were irradiated with 5 MeV Fe2+ ions at fluences ranging from 0.01 to 1.0 displacements per atom (dpa) and the induced hardening of the surface layer was probed with nanoindentation. To separate the indentation size effect and the substrate effect from the irradiation-induced hardness profile, we developed an analytic model with the plastic zone of the indentation approximated as a half sphere. This model allows the actual hardness profile to be retrieved and the measured hardness increase to be assigned to the respective fluence. The obtained values of hardness increase vs. fluence are compared for selected pairs of samples in order to extract effects of the RPV steel composition. We identify hardening effects due to increased levels of copper, manganese-nickel and phosphorous. Further comparison with available neutron-irradiated conditions of the same heats of RPV steels indicates pronounced differences of the considered effects of composition for irradiation with neutrons vs. ions.

Global solar wind variations over the last four centuries.

PubMed

Owens, M J; Lockwood, M; Riley, P

2017-01-31

The most recent "grand minimum" of solar activity, the Maunder minimum (MM, 1650-1710), is of great interest both for understanding the solar dynamo and providing insight into possible future heliospheric conditions. Here, we use nearly 30 years of output from a data-constrained magnetohydrodynamic model of the solar corona to calibrate heliospheric reconstructions based solely on sunspot observations. Using these empirical relations, we produce the first quantitative estimate of global solar wind variations over the last 400 years. Relative to the modern era, the MM shows a factor 2 reduction in near-Earth heliospheric magnetic field strength and solar wind speed, and up to a factor 4 increase in solar wind Mach number. Thus solar wind energy input into the Earth's magnetosphere was reduced, resulting in a more Jupiter-like system, in agreement with the dearth of auroral reports from the time. The global heliosphere was both smaller and more symmetric under MM conditions, which has implications for the interpretation of cosmogenic radionuclide data and resulting total solar irradiance estimates during grand minima.

Global solar wind variations over the last four centuries

PubMed Central

Owens, M. J.; Lockwood, M.; Riley, P.

2017-01-01

The most recent “grand minimum” of solar activity, the Maunder minimum (MM, 1650–1710), is of great interest both for understanding the solar dynamo and providing insight into possible future heliospheric conditions. Here, we use nearly 30 years of output from a data-constrained magnetohydrodynamic model of the solar corona to calibrate heliospheric reconstructions based solely on sunspot observations. Using these empirical relations, we produce the first quantitative estimate of global solar wind variations over the last 400 years. Relative to the modern era, the MM shows a factor 2 reduction in near-Earth heliospheric magnetic field strength and solar wind speed, and up to a factor 4 increase in solar wind Mach number. Thus solar wind energy input into the Earth’s magnetosphere was reduced, resulting in a more Jupiter-like system, in agreement with the dearth of auroral reports from the time. The global heliosphere was both smaller and more symmetric under MM conditions, which has implications for the interpretation of cosmogenic radionuclide data and resulting total solar irradiance estimates during grand minima. PMID:28139769

Phytosanitary irradiation in south Asia

USDA-ARS?s Scientific Manuscript database

Irradiation has the potential to solve phytosanitary problems related to trade in south Asia. In general, it is the phytosanitary treatment most tolerated by fresh agricultural commodities. Irradiation technology is available in some countries of the region but is only used for phytosanitary purpos...

Accessing Solar Irradiance Data Products From the LASP Interactive Solar IRradiance Datacenter (LISIRD)

NASA Astrophysics Data System (ADS)

Ware Dewolfe, A.; Wilson, A.; Lindholm, D. M.; Pankratz, C. K.; Snow, M.; Woods, T. N.

2009-12-01

The Laboratory for Atmospheric and Space Physics (LASP) is enhancing the LASP Interactive Solar IRradiance Datacenter (LISIRD) to provide access to a comprehensive set of solar spectral irradiance measurements. LISIRD has recently been updated to serve many new datasets and models, including sunspot index, photometric sunspot index, Lyman-alpha, and magnesium-II core-to-wing ratio. A new user interface emphasizes web-based interactive visualizations, allowing users to explore and compare this data before downloading it for analysis. The data provided covers a wavelength range from soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as wavelength-independent Total Solar Irradiance (TSI). Combined data from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments provide almost continuous coverage from 1981 to the present, while Hydrogen Lyman-alpha (121.6 nm) measurements / models date from 1947 to the present. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD interfaces at http://lasp.colorado.edu/lisird/.

[Near infrared light irradiator using halogen lamp].

PubMed

Ide, Yasuo

2012-07-01

The practical electric light bulb was invented by Thomas Alva Edison in 1879. Halogen lamp is the toughest and brightest electric light bulb. With light filter, it is used as a source of near infrared light. Super Lizer and Alphabeam are made as near infrared light irradiator using halogen lamp. The light emmited by Super Lizer is linear polarized near infrared light. The wave length is from 600 to 1,600 nm and strongest at about 1,000 nm. Concerning Super Lizer, there is evidence of analgesic effects and normalization of the sympathetic nervous system. Super Lizer has four types of probes. SG type is used for stellate ganglion irradiation. B type is used for narrow area irradiation. C and D types are for broad area irradiation. The output of Alphabeam is not polarized. The wave length is from 700 to 1,600 nm and the strongest length is about 1,000nm. Standard attachment is used for spot irradiation. Small attachment is used for stellate ganglion irradiation. Wide attachment is used for broad area irradiation. The effects of Alphabeam are thought to be similar to that of Super Lizer.

Solar Spectral Irradiance Reconstruction over 9 Millennia from a Composite 14C and 10Be Series

NASA Astrophysics Data System (ADS)

Wu, C. J.; Usoskin, I. G.; Krivova, N.; Kovaltsov, G.; Solanki, S. K.

2017-12-01

The Sun is the main external energy source to the Earth and thus the knowledge of solar variability on different time scales is important for understanding the solar influence on the terrestrial atmosphere and climate. The overall energy input and its spectral distribution are described by the total (TSI) and spectral (SSI) solar irradiance, respectively. Direct measurements of the solar irradiance provide information on solar variability on the decadal and shorter time scales, while the sunspot number record covers four centuries. On yet longer time scales only indirect proxies can be used, such as the concentrations of the cosmogenic isotopes 10Be and 14C in terrestrial archives. These isotopes are produced in the terrestrial atmosphere by impinging cosmic rays, whose flux is modulated by solar activity. Therefore the isotope data retrieved from various natural archives around the globe show a very high degree of similarity reflecting changes in the solar activity. Nevertheless, significant short-term deviations can be observed due to the different geochemical production processes and local climatic conditions. We will present the newest TSI/SSI reconstruction over the last 9000 years based on a new consistent composite multi-isotope proxy series. The solar irradiance reconstruction reveals the global and robust pattern of solar variability in the past.

Measurements of global UV irradiance at Terranova Bay, Antactica, by a home made narrow band filter radiometer

NASA Astrophysics Data System (ADS)

Salvatore, Scaglione; di Sarcina, Ilaria; Flori, Daniele; Menchini, Francesca

2010-05-01

Filter radiometers measure the solar radiation in several channels (typically 4 to 7) with a bandwith from 2 to 10 nm. They require less maintenance than the spectroradiometer and they are able to work in hostile environment as for instance the polar regions. The spectral resolution depends on the width at half maximum (FWHM) of the filters and is generally lower than the spectroradiometer resolution (0.5 nm). Other than the robustness of this instruments, the main advantage of the filter radiometers is the high frequency with which all wavelengths can be measured, making this class of instrument well suited for investigating short term irradiance variation. In this work is presented the results of UV irradiance measurements performed by a very narrow band (FWHM less than 1 nm) filter radiometer at Antarctica Italia Base, Mario Zucchelli Station, Terranova Bay, lat. 74° 41.6084' south and lon. 164° 05.9224' est. All-dielectric Fabry-Perot filters were manufactured in the laboratories of the Optical Coating Group, ENEA, by the ion beam assistance physical vapor deposition technique. Nine filters select nine different wavelengths in the UV spectral range from 296.5 nm to 377 nm with about 1 minute of measurement period, i.e. each wavelength is measured about 1250 times per day. At the moment the radiometer are permanently located near MZS and the data are daily downloaded in ENEA, Rome, by a dedicated satellite channel. During the Antarctica winter the radiometer will be in standby mode, in this season MZS is closed, and it will be start to measure again in the Antarctica spring.

High-dose neutron irradiation embrittlement of RAFM steels

NASA Astrophysics Data System (ADS)

Gaganidze, E.; Schneider, H.-C.; Dafferner, B.; Aktaa, J.

2006-09-01

Neutron irradiation-induced embrittlement of the reduced-activation ferritic/martensitic (RAFM) steel EUROFER97 was studied under different heat treatment conditions. Irradiation was performed in the Petten High Flux Reactor within the HFR Phase-IIb (SPICE) irradiation project up to 16.3 dpa and at different irradiation temperatures (250-450 °C). Several reference RAFM steels (F82H-mod, OPTIFER-Ia, GA3X and MANET-I) were also irradiated at selected temperatures. The impact properties were investigated by instrumented Charpy-V tests with subsize specimens. Embrittlement and hardening of as-delivered EUROFER97 steel are comparable to those of reference steels. Heat treatment of EUROFER97 at a higher austenitizing temperature substantially improves the embrittlement behaviour at low irradiation temperatures. Analysis of embrittlement in terms of the parameter C = ΔDBTT/Δ σ indicates hardening-dominated embrittlement at irradiation temperatures below 350 °C with 0.17 ⩽ C ⩽ 0.53 °C/MPa. Scattering of C at irradiation temperatures above 400 °C indicates no hardening embrittlement.

Thermal conductivity of electron-irradiated graphene

NASA Astrophysics Data System (ADS)

Weerasinghe, Asanka; Ramasubramaniam, Ashwin; Maroudas, Dimitrios

2017-10-01

We report results of a systematic analysis of thermal transport in electron-irradiated, including irradiation-induced amorphous, graphene sheets based on nonequilibrium molecular-dynamics simulations. We focus on the dependence of the thermal conductivity, k, of the irradiated graphene sheets on the inserted irradiation defect density, c, as well as the extent of defect passivation with hydrogen atoms. While the thermal conductivity of irradiated graphene decreases precipitously from that of pristine graphene, k0, upon introducing a low vacancy concentration, c < 1%, in the graphene lattice, further reduction of the thermal conductivity with the increasing vacancy concentration exhibits a weaker dependence on c until the amorphization threshold. Beyond the onset of amorphization, the dependence of thermal conductivity on the vacancy concentration becomes significantly weaker, and k practically reaches a plateau value. Throughout the range of c and at all hydrogenation levels examined, the correlation k = k0(1 + αc)-1 gives an excellent description of the simulation results. The value of the coefficient α captures the overall strength of the numerous phonon scattering centers in the irradiated graphene sheets, which include monovacancies, vacancy clusters, carbon ring reconstructions, disorder, and a rough nonplanar sheet morphology. Hydrogen passivation increases the value of α, but the effect becomes very minor beyond the amorphization threshold.

Whole-Body Imaging of High-Dose Ionizing Irradiation-Induced Tissue Injuries Using 99mTc-Duramycin

PubMed Central

Johnson, Steven E.; Li, Zhixin; Liu, Yu; Moulder, John E.; Zhao, Ming

2013-01-01

be useful for global, whole-body, assessment of tissue damage after radiation exposure. These data, in turn, will contribute to our general knowledge of tissue susceptibility to ionizing irradiation, as well as the onset and progression of tissue injuries. PMID:23804327

Study into the identification of irradiation ground paprika

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beczner, J.; Farkas, J.; Kiss, I.

From international colloquium: the identification of irradiated foodstuffs; Karlsruhe, Germany (24 Oct 1973). Several methods for the demonstration of irradiation in ground paprika were tested. In carbonyl compounds extracted by steam distillation unambiguous changes, which might have served as a basis for detecting irradiation, were not observed. Derivatography did not prove suitable either. On the basis of the size of ESR signal, the control sample and the irradiated one could be distinguished 2 to 3 weeks after irradiation. After a longer storage period, the size of the signal is irrelevant. Further study of the shape of the ESR signals maymore » yield valuable information in experiments on the demonstration of irradiation. (GE)« less

Microstructural evolution of nanochannel CrN films under ion irradiation at elevated temperature and post-irradiation annealing

NASA Astrophysics Data System (ADS)

Tang, Jun; Hong, Mengqing; Wang, Yongqiang; Qin, Wenjing; Ren, Feng; Dong, Lan; Wang, Hui; Hu, Lulu; Cai, Guangxu; Jiang, Changzhong

2018-03-01

High-performance radiation tolerance materials are crucial for the success of future advanced nuclear reactors. In this paper, we present a further investigation that the "vein-like" nanochannel films can enhance radiation tolerance under ion irradiation at high temperature and post-irradiation annealing. The chromium nitride (CrN) nanochannel films with different nanochannel densities and the compact CrN film are chosen as a model system for these studies. Microstructural evolution of these films were investigated using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Elastic Recoil Detection (ERD) and Grazing Incidence X-ray Diffraction (GIXRD). Under the high fluence He+ ion irradiation at 500 °C, small He bubbles with low bubble densities are observed in the irradiated nanochannel CrN films, while the aligned large He bubbles, blistering and texture reconstruction are found in the irradiated compact CrN film. For the heavy Ar2+ ion irradiation at 500 °C, the microstructure of the nanochannel CrN RT film is more stable than that of the compact CrN film due to the effective releasing of defects via the nanochannel structure. Under the He+ ion irradiation and subsequent annealing, compared with the compact film, the nanochannel films have excellent performance for the suppression of He bubble growth and possess the strong microstructural stability. Basing on the analysis on the sizes and number densities of bubbles as well as the concentrations of He retained in the nanochannel CrN films and the compact CrN film under different experimental conditions, potential mechanism for the enhanced radiation tolerance are discussed. Nanochannels play a crucial role on the release of He/defects under ion irradiation. We conclude that the tailored "vein-like" nanochannel structure may be used as advanced radiation tolerance materials for future nuclear reactors.

Total ozone column retrieval from UV-MFRSR irradiance measurements: evaluation at Mauna Loa station

NASA Astrophysics Data System (ADS)

Zempila, Melina Maria; Fragkos, Konstantinos; Davis, John; Sun, Zhibin; Chen, Maosi; Gao, Wei

2017-09-01

The USDA UV-B Monitoring and Research Program (UVMRP) comprises of 36 climatological sites along with 4 long-duration research sites, in 27 states, one Canadian province, and the south island of New Zealand. Each station is equipped with an Ultraviolet multi-filter rotating shadowband radiometer (UV-MFRSR) which can provide response-weighted irradiances at 7 wavelengths (300, 305.5, 311.4, 317.6, 325.4, and 368 nm) with a nominal full width at half maximun of 2 nm. These UV irradiance data from the long term monitoring station at Mauna Loa, Hawaii, are used as input to a retrieval algorithm in order to derive high time frequency total ozone columns. The sensitivity of the algorithm to the different wavelength inputs is tested and the uncertainty of the retrievals is assessed based on error propagation methods. For the validation of the method, collocated hourly ozone data from the Dobson Network of the Global Monitoring Division (GMD) of the Earth System Radiation Laboratory (ESRL) under the jurisdiction of the US National Oceanic & Atmospheric Administration (NOAA) for the period 2010-2015 were used.

THE EFFECT OF IRRADIATION ON REPRODUCTION BY THE HETEROGENETIC GENERATION OF STRONGYLOIDES PAPILLOSUS. I. IRRADIATION OF MALES AND FEMALES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katz, F.F.

1960-06-01

Fourth and fifth stage male and third and fourth stage female S. papillosus were subjected to various doses of Co/sup 60/ gamma irradiation and cultured in vitro with controls of the opposite sex. Fewer offspring were produced in cultures containing irradiated males than in cultures of irradiated females. A single experiment involving several doses and one control gave a more linear picture of the effects of irradiation than individual experiments carried out at various times for different dose levels. In the former, larvae were obtained in cultures of nematodes exposed to 20 kr but not to 40, 60, 80 ormore » 100 kr; in the latter, larvae occurred in cultures of males irradiated at 42 kr and in cultures of females exposed to 50 kr but not at the higher levels employed. With increased doses of irradiation, there was a decrease in the percentage of eggs hatching. The dominant lethal effect was observed in cultures with males exposed to 20 kr and higher doses. In cultures with irradiated females, this phenomenon was observed at 40 kr and higher levels. (auth)« less

Emulation of reactor irradiation damage using ion beams

DOE PAGES

Was, G. S.; Jiao, Z.; Getto, E.; ...

2014-06-14

The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide,more » irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiation and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiation establishes the capability of tailoring ion irradiation to emulate the reactor-irradiated microstructure.« less

Food irradiation for phytosanitary and quarantine treatment

USDA-ARS?s Scientific Manuscript database

Irradiation at doses less than 1 kGy is an effective phytosanitary measure with minimal adverse effects on the quality of most fresh produce. There are internationally recognized guidelines for the use of irradiation as a phytosanitary measure and for the conduct of trade in irradiated fresh produce...

Reconstruction of solar spectral surface UV irradiances using radiative transfer simulations.

PubMed

Lindfors, Anders; Heikkilä, Anu; Kaurola, Jussi; Koskela, Tapani; Lakkala, Kaisa

2009-01-01

UV radiation exerts several effects concerning life on Earth, and spectral information on the prevailing UV radiation conditions is needed in order to study each of these effects. In this paper, we present a method for reconstruction of solar spectral UV irradiances at the Earth's surface. The method, which is a further development of an earlier published method for reconstruction of erythemally weighted UV, relies on radiative transfer simulations, and takes as input (1) the effective cloud optical depth as inferred from pyranometer measurements of global radiation (300-3000 nm); (2) the total ozone column; (3) the surface albedo as estimated from measurements of snow depth; (4) the total water vapor column; and (5) the altitude of the location. Reconstructed daily cumulative spectral irradiances at Jokioinen and Sodankylä in Finland are, in general, in good agreement with measurements. The mean percentage difference, for instance, is mostly within +/-8%, and the root mean square of the percentage difference is around 10% or below for wavelengths over 310 nm and daily minimum solar zenith angles (SZA) less than 70 degrees . In this study, we used pseudospherical radiative transfer simulations, which were shown to improve the performance of our method under large SZA (low Sun).

Cost effective alternative to low irradiance measurements

NASA Technical Reports Server (NTRS)

Oleary, Scott T.

1988-01-01

Martin Marietta's Space Simulation Laboratory (SSL) has a Thermal Environment Simulator (TES) with 56 individually controlled heater zones. The TES has a temperature range of approximately minus 129 C to plus 149 C. Because of the ability of TES to provide complex irradiance distributions, it is necessary to be able to measure a wide range of irradiance levels. SSL currently uses ambient temperature controlled radiometers with the capacity to measure sink irradiance levels of approximately 42.6 mw/sq cm, sink temperature equals 21 C and up. These radiometers could not be used to accurately measure the lower irradiance levels of the TES. Therefore, it was necessary to obtain a radiometer or develop techniques which could be used to measure lower irradiance levels.

Classification of daily solar irradiation by fractional analysis of 10-min-means of solar irradiance

NASA Astrophysics Data System (ADS)

Harrouni, S.; Guessoum, A.; Maafi, A.

2005-02-01

This paper deals with fractal analysis of daily solar irradiances measured with a time step of 10 minutes at Golden and Boulder located in Colorado. The aim is to estimate the fractal dimensions in order to perform classification of daily solar irradiances. The estimated fractal dimension hat{D} and the clearness index KT are used as classification criteria. The results show that these criteria lead to three classes: clear sky, partially covered sky and overcast sky. The results also show that the evaluation of the fractal dimension of the irradiance signal based on a data set with 10 minutes time step is possible.

10 CFR 36.69 - Irradiation of explosive or flammable materials.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Irradiation of explosive or flammable materials. 36.69... IRRADIATORS Operation of Irradiators § 36.69 Irradiation of explosive or flammable materials. (a) Irradiation... cause radiation overexposures of personnel. (b) Irradiation of more than small quantities of flammable...

10 CFR 36.69 - Irradiation of explosive or flammable materials.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Irradiation of explosive or flammable materials. 36.69... IRRADIATORS Operation of Irradiators § 36.69 Irradiation of explosive or flammable materials. (a) Irradiation... cause radiation overexposures of personnel. (b) Irradiation of more than small quantities of flammable...

10 CFR 36.69 - Irradiation of explosive or flammable materials.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Irradiation of explosive or flammable materials. 36.69... IRRADIATORS Operation of Irradiators § 36.69 Irradiation of explosive or flammable materials. (a) Irradiation... cause radiation overexposures of personnel. (b) Irradiation of more than small quantities of flammable...

10 CFR 36.69 - Irradiation of explosive or flammable materials.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Irradiation of explosive or flammable materials. 36.69... IRRADIATORS Operation of Irradiators § 36.69 Irradiation of explosive or flammable materials. (a) Irradiation... cause radiation overexposures of personnel. (b) Irradiation of more than small quantities of flammable...

10 CFR 36.69 - Irradiation of explosive or flammable materials.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Irradiation of explosive or flammable materials. 36.69... IRRADIATORS Operation of Irradiators § 36.69 Irradiation of explosive or flammable materials. (a) Irradiation... cause radiation overexposures of personnel. (b) Irradiation of more than small quantities of flammable...

A Practical Irradiance Model for Bifacial PV Modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marion, Bill; MacAlpine, Sara; Deline, Chris

2017-06-21

A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of configuration factors to determine the fraction of a source of irradiance that is received by the backside of the PV module. Backside irradiances are modeled along the sloped height of the PV module, but assumed not to vary along the length of the PV row. The backside irradiances are corrected for angle-of-incidence losses and may be added tomore » the front side irradiance to determine the total irradiance resource for the PV cell. Model results are compared with the measured backside irradiances for NREL and Sandia PV systems, and with results when using ray tracing software.« less

DYNAMIC MECHANICAL STUDIES OF IRRADIATED POLYPROPYLENE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sauer, J.A.; Merrill, L.J.; Woodward, A.E.

1962-04-01

The internal friction and the dynamic modulus of isotactic polypropylene samples subject to varying degrees of pile irradiation were studied at low audio frequencies and over the temperature range from 100 to over 400 deg K. The radiation dosages used varied from 5.4 x lO/sup 17/ to 14 x lO/sup 18/ nvt. For irradiation doses up to about 3 x lO/sup 18/ nvt, one observed change is a decrease in the temperature at which the final upswing in damping and drop in modulus occurs, presumably as a result of defects produced in the crystallites by the irradiation. As the irradiationmore » dose increases above 3 x lO/sup 18/ nvt, all evidence of crystallinity is lost, and the internal friction peak which occurs in the neighborhood of 300 deg K and which is associated with the glass transition of the amorphous regions moves to higher temperatures as a result of the increasing chain-stiffening effect due to crosslinking. The secondary loss peak at 250 deg K attributed to the motion of a small number of segraents in the amorphous regions is found to increase in magnitude with increasing dose. The results of density determinations raade before and after irradiation and also after subsequent exposure of the irradiated samples to melting temperatures and of solvent extraction studies of the irradiated samples confirm the simultaneous occurrence of crosslinking and of crystalline degradation upon pile irradiation of polypropylene samples. (auth)« less

Study of properties of tungsten irradiated in hydrogen atmosphere

NASA Astrophysics Data System (ADS)

Tazhibayeva, I.; Skakov, M.; Baklanov, V.; Koyanbayev, E.; Miniyazov, A.; Kulsartov, T.; Ponkratov, Yu.; Gordienko, Yu.; Zaurbekova, Zh.; Kukushkin, I.; Nesterov, E.

2017-12-01

The paper presents the results of the experiments with DF (double forged) tungsten samples irradiated at the WWR-K research reactor in hydrogen and helium atmospheres. The irradiation time was 3255 h (135.6 d). After reactor irradiation, W samples have been subjected to investigations of their activity level, hardness, and microstructure, as well as x-ray and texture observations. The hydrogen yield released from irradiated tungsten samples have been measured using TDS-method. The hydrogen concentration in the tungsten samples irradiated in hydrogen was higher than that in the samples irradiated in helium atmosphere. It is shown that the surface microstructure of tungsten samples irradiated in hydrogen is characterized by micro-pits, inclusions and blisters in the form of bubbles, which were not observed earlier for tungsten irradiated in hydrogen.

FOOD IRRADIATION REACTOR

DOEpatents

Leyse, C.F.; Putnam, G.E.

1961-05-01

An irradiation apparatus is described. It comprises a pressure vessel, a neutronic reactor active portion having a substantially greater height than diameter in the pressure vessel, an annular tank surrounding and spaced from the pressure vessel containing an aqueous indium/sup 1//sup 1//sup 5/ sulfate solution of approximately 600 grams per liter concentration, means for circulating separate coolants through the active portion and the space between the annular tank and the pressure vessel, radiator means adapted to receive the materials to be irradiated, and means for flowing the indium/sup 1//sup 1//sup 5/ sulfate solution through the radiator means.

RESULTS OF THE CANADIAN PILOT SCALE POTATO IRRADIATION PROGRAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1963-04-01

ABS>A potato irradiation program using a Mobile Cobalt-60 Irradiator was carried out in four provinces of Eastern Canada during the 1961-82 season in cooperation with twenty-six members of the potato industry. A total of 400 tons of potatoes was irradiated over a four months' period extending from October to February. Regular observations on both control and irradiated potatoes were conducted during storage by the Fruit and Vegetable Division of the Canada Department of Agriculture until final shipment to consumer markets or processing plants. The dose of 8,000 rads used in the program provided excellent control of sprouting in all storagesmore » regardless of variety, storage temperature, date of irradiation, method of storage or length of storage. When good material suitable for long term storage was irradiated and not mishandled during treatment, there was no effect on the rate of breakdown during storage. Irradiated potatoes were successfully processed into potato chips, instant mashed potato flakes, frozen french fries and pre-peeled fresh boilers. Irradiated potatoes were sold to Canadian consumers in the form of table stock and processed products. No complaints of any kind were received or reported regarding the acceptability of the irradiated potatoes. There was no unfavorable public reaction to the first irradiated food offered for sale in Canada. The results of the potato irradiation program have created a favorable climate for the future of potato irradiation in Canada. The operation of full scale irradiation facilities is envisaged within the next two years. (auth)« less

IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS

DOEpatents

Allen, A.O.; Caffrey, J.M. Jr.

1960-10-11

A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

Patterns and Variability in Global Ocean Chlorophyll: Satellite Observations and Modeling

NASA Technical Reports Server (NTRS)

Gregg, Watson

2004-01-01

Recent analyses of SeaWiFS data have shown that global ocean chlorophyll has increased more than 4% since 1998. The North Pacific ocean basin has increased nearly 19%. These trend analyses follow earlier results showing decadal declines in global ocean chlorophyll and primary production. To understand the causes of these changes and trends we have applied the newly developed NASA Ocean Biogeochemical Assimilation Model (OBAM), which is driven in mechanistic fashion by surface winds, sea surface temperature, atmospheric iron deposition, sea ice, and surface irradiance. The model utilizes chlorophyll from SeaWiFS in a daily assimilation. The model has in place many of the climatic variables that can be expected to produce the changes observed in SeaWiFS data. This enables us to diagnose the model performance, the assimilation performance, and possible causes for the increase in chlorophyll. A full discussion of the changes and trends, possible causes, modeling approaches, and data assimilation will be the focus of the seminar.

Focal exposure of limited lung volumes to high-dose irradiation down-regulated organ development-related functions and up-regulated the immune response in mouse pulmonary tissues.

PubMed

Kim, Bu-Yeo; Jin, Hee; Lee, Yoon-Jin; Kang, Ga-Young; Cho, Jaeho; Lee, Yun-Sil

2016-01-27

neighboring areas of lung tissue, indicating a global lung response to focal high-dose irradiation.

Identification of gamma-irradiated papaya, melon and watermelon

NASA Astrophysics Data System (ADS)

Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

2004-09-01

Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

The status of food irradiation technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sivinski, J.S.

1989-01-01

Irradiation is a mature technology for many uses, such as medical product sterilization, crosslinking of plastics, application of coatings, stabilization of natural and synthetic rubbers prior to vulcanization, and in plant genetics. It also has many potential applications in the food and agriculture industries, especially in the postharvest activities associated with processing, storing, and distribution and in utilization and consumption. The safety of food irradiation has been thoroughly studied and established by distinguished scientists of international stature and unimpeachable credentials. Approximately 30 countries permit food irradiation and it is commercially used in 21. Parasites are of serious concern since theirmore » impact on human health and economic productivity is significant, especially in developing countries with sanitation and food control problems. Parasites in meat and fish can be rendered sterile or inactivated with irradiation, and the potential for improved human health is significant. The second area for immediate use of irradiation is in meeting plant quarantine requirements. The benefits described above and the approval of the scientific community are moving the technology toward greater utilization.« less

Food irradiation: Public opinion surveys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kerr, S.D.

The Canadian government are discussing the legislation, regulations and practical protocol necessary for the commercialization of food irradiation. Food industry marketing, public relations and media expertise will be needed to successfully introduce this new processing choice to retailers and consumers. Consumer research to date including consumer opinion studies and market trials conducted in the Netherlands, United States, South Africa and Canada will be explored for signposts to successful approaches to the introduction of irradiated foods to retailers and consumers. Research has indicated that the terms used to describe irradiation and information designed to reduce consumer fears will be important marketingmore » tools. Marketers will be challenged to promote old foods, which look the same to consumers, in a new light. Simple like or dislike or intention to buy surveys will not be effective tools. Consumer fears must be identified and effectively handled to support a receptive climate for irradiated food products. A cooperative government, industry, health professional, consumer association and retailer effort will be necessary for the successful introduction of irradiated foods into the marketplace. Grocery Products Manufacturers of Canada is a national trade association of more than 150 major companies engaged in the manufacture of food, non-alcoholic beverages and array of other national-brand consumer items sold through retail outlets.« less

Solar EUV irradiance for space weather applications

NASA Astrophysics Data System (ADS)

Viereck, R. A.

2015-12-01

Solar EUV irradiance is an important driver of space weather models. Large changes in EUV and x-ray irradiances create large variability in the ionosphere and thermosphere. Proxies such as the F10.7 cm radio flux, have provided reasonable estimates of the EUV flux but as the space weather models become more accurate and the demands of the customers become more stringent, proxies are no longer adequate. Furthermore, proxies are often provided only on a daily basis and shorter time scales are becoming important. Also, there is a growing need for multi-day forecasts of solar EUV irradiance to drive space weather forecast models. In this presentation we will describe the needs and requirements for solar EUV irradiance information from the space weather modeler's perspective. We will then translate these requirements into solar observational requirements such as spectral resolution and irradiance accuracy. We will also describe the activities at NOAA to provide long-term solar EUV irradiance observations and derived products that are needed for real-time space weather modeling.

Position of the American Dietetic Association: food irradiation.

PubMed

Wood, O B; Bruhn, C M

2000-02-01

Food irradiation has been identified a sa safe technology to reduce the risk of foodborne illness as part of high-quality food production, processing, handling, and preparation. Food irradiation's history of scientific research , evaluation, and testing spans more than 40 countries around the world and it has been endorsed or support by numerous national and international food and organizations and professional groups. Food irradiation utilizes a source of ionizing energy that passes through food to destroy harmful bacteria and other organism. Often referred to as "cold pasteurization," food irradiation offers negligible loss of nutrients or sensory qualities in food as it does not substantially raise the temperature of the food during processing. Food irradiation does not replace proper food production, processing, handling, or preparation, nor can it enhance the quality of or prevent contact with foodborne bacteria after irradiation. In the United States, manufacturers are required to identify irradiated food sold to consumers with an international symbol (Radura) and and terminology describing the process on product labels. In addiction, food irradiation facilities are thoroughly regulated and monitored for worker and environmental safety. Members of The American Dietetic Association (ADA) and other food, nutrition, and health professionals have a responsibility to educate consumers, food processors, manufacturers and retailers about the safety and application of the technology. When consumers are educated about food irradiation, many prefer irradiated products because of their increased safety. It is the position of ADA that food irradiation enhances the safety and quality of the food supply and helps protect consumers from foodborne illness. The ADA encourages the government, food manufactures, food commodity groups, and qualified food and nutrition professionals to work together to educate consumers about this additional food safety tool and make this choice

Effect of gamma irradiation on Korean traditional multicolored paintwork

NASA Astrophysics Data System (ADS)

Yoon, Minchul; Kim, Dae-Woon; Choi, Jong-il; Chung, Yong-Jae; Kang, Dai-Ill; Hoon Kim, Gwang; Son, Kwang-Tae; Park, Hae-Jun; Lee, Ju-Woon

2015-10-01

Gamma irradiation can destroy fungi and insects involved in the bio-deterioration of organic cultural heritages. However, this irradiation procedure can alter optical and structural properties of historical pigments used in wooden cultural heritage paintings. The crystal structure and color centers of these paintings must be maintained after application of the irradiation procedure. In this study, we investigated the effects of gamma irradiation on Korean traditional multicolored paintwork (Dancheong) for the preservation of wooden cultural heritages. The main pigments in Korean traditional wooden cultural heritages, Sukganju (Hematite; Fe2O3), Jangdan (Minium; Pb3O4), Whangyun (Crocoite; PbCrO4), and Jidang (Rutile; TiO2), were irradiated by gamma radiation at doses of 1, 5, and 20 kGy. After irradiation, changes in Commision Internationale d'Eclairage (CIE) color values (L*, a*, b*) were measured using the color difference meter, and their structural changes were analyzed using X-ray diffraction (XRD) analysis. The slightly change in less than 1 dE* unit by gamma irradiation was observed, and structural changes in the Dancheong were stable after exposure to 20 kGy gamma irradiation. In addition, gamma irradiation could be applied to painted wooden cultural properties from the Korean Temple. Based on the color values, gamma irradiation of 20 kGy did not affect the Dancheong and stability was maintained for five months. In addition, the fungicidal and insecticidal effect by less than 5 kGy gamma irradiation was conformed. Therefore, the optical and structural properties of Dancheong were maintained after gamma irradiation, which suggested that gamma irradiation can be used for the preservation of wooden cultural heritages painted with Dancheong.

Preservation of food products by irradiation.

PubMed

McGivney, W T

1988-01-01

The use of irradiation to preserve food has the potential to significantly enhance our capacity to maximize the quality and quantity of the food we consume. In a world in which distribution of food occurs across continents and in which malnourished populations are in dire need of basic food products, any safe, effective, and efficient means of preserving food is more than welcome. Irradiation, as a method for food preservation, has been studied for more than 30 years. This discussion focuses on this most recent method for the preservation of food with particular emphasis on its effects on the safety, nutritive, and aesthetic values of the food preserved by irradiation. The use of ionizing radiation as a method to preserve foods is one that has been demonstrated to be effective for a variety of food classes. Irradiation offers a means to decontaminate, disinfest, and retard the spoilage of the food supply. At the same time, it appears that the wholesomeness of these food products is maintained. Nutritive value can be sustained by use of effective doses of radiation. Concerns over the safety of irradiated food are rooted in questions regarding the potential induction of radioactivity, harmful radiolytic products, and pathogenic radiation-resistant or mutant strains of microorganisms. Research findings have allayed concerns over safety. However, more research is necessary to conclusively resolve these safety issues. Food irradiation is a promising technology that has and will contribute to our ability to feed the people of this world. This technology is but one of many available ways to preserve our greatest natural resource, the food supply. Enhancement of the ability to preserve food by irradiation will facilitate the distribution of food from fertile developed regions to the malnourished peoples of underdeveloped countries. It is in diminishing the problem of malnourishment and starvation that irradiation as a means to preserve food may find the greatest acceptance.

High accuracy diffuse horizontal irradiance measurements without a shadowband

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlemmer, J.A; Michalsky, J.J.

1995-12-31

The standard method for measuring diffuse horizontal irradiance uses a fixed shadowband to block direct solar radiation. This method requires a correction for the excess skylight blocked by the band, and this correction varies with sky conditions. Alternately, diffuse horizontal irradiance may be calculated from total horizontal and direct normal irradiance. This method is in error because of angular (cosine) response of the total horizontal pyranometer to direct beam irradiance. This paper describes an improved calculation of diffuse horizontal irradiance from total horizontal and direct normal irradiance using a predetermination of the angular response of the total horizontal pyranometer. Wemore » compare these diffuse horizontal irradiance calculations with measurements made with a shading-disk pyranometer that shields direct irradiance using a tracking disk. Results indicate significant improvement in most cases. Remaining disagreement most likely arises from undetected tracking errors and instrument leveling.« less

Low dose irradiation facilitates hepatocellular carcinoma genesis involving HULC.

PubMed

Li, Yuan; Ge, Chang; Feng, Guoxing; Xiao, Huiwen; Dong, Jiali; Zhu, Changchun; Jiang, Mian; Cui, Ming; Fan, Saijun

2018-03-24

Irradiation exposure positive correlates with tumor formation, such as breast cancer and lung cancer. However, whether low dose irradiation induces hepatocarcinogenesis and the underlying mechanism remain poorly defined. In the present study, we reported that low dose irradiation facilitated the proliferation of hepatocyte through up-regulating HULC in vitro and in vivo. Low dose irradiation exposure elevated HULC expression level in hepatocyte. Deletion of heightened HULC erased the cells growth accelerated following low dose irradiation exposure. CDKN1, the neighbor gene of HULC, was down-regulated by overexpression of HULC following low dose irradiation exposure via complementary base pairing, resulting in promoting cell cycle process. Thus, our findings provide new insights into the mechanism of low dose irradiation-induced hepatocarcinogenesis through HULC/CDKN1 signaling, and shed light on the potential risk of low dose irradiation for the development of hepatocellular carcinoma in pre-clinical settings. © 2018 Wiley Periodicals, Inc.

Data on total and spectral solar irradiance

NASA Technical Reports Server (NTRS)

Mecherikunnel, A. T.; Gatlin, J. A.; Richmond, J. C.

1983-01-01

This paper presents a brief survey of the data available on solar constant and extraterrestrial solar spectral irradiance. The spectral distribution of solar radiation at ground surface, computed from extraterrestrial solar spectral irradiance for several air mass values and for four levels of atmospheric pollution, is also presented. The total irradiance at ground level is obtained by integration of the area under the spectral irradiance curves. It is significant that, as air mass increases or as turbidity increases, the amount of energy in the infrared relative to the total increases and that the energy in the UV and visible decreases.

Quantitative assessment of drivers of recent global temperature variability: an information theoretic approach

NASA Astrophysics Data System (ADS)

Bhaskar, Ankush; Ramesh, Durbha Sai; Vichare, Geeta; Koganti, Triven; Gurubaran, S.

2017-12-01

Identification and quantification of possible drivers of recent global temperature variability remains a challenging task. This important issue is addressed adopting a non-parametric information theory technique, the Transfer Entropy and its normalized variant. It distinctly quantifies actual information exchanged along with the directional flow of information between any two variables with no bearing on their common history or inputs, unlike correlation, mutual information etc. Measurements of greenhouse gases: CO2, CH4 and N2O; volcanic aerosols; solar activity: UV radiation, total solar irradiance ( TSI) and cosmic ray flux ( CR); El Niño Southern Oscillation ( ENSO) and Global Mean Temperature Anomaly ( GMTA) made during 1984-2005 are utilized to distinguish driving and responding signals of global temperature variability. Estimates of their relative contributions reveal that CO2 ({˜ } 24 %), CH4 ({˜ } 19 %) and volcanic aerosols ({˜ }23 %) are the primary contributors to the observed variations in GMTA. While, UV ({˜ } 9 %) and ENSO ({˜ } 12 %) act as secondary drivers of variations in the GMTA, the remaining play a marginal role in the observed recent global temperature variability. Interestingly, ENSO and GMTA mutually drive each other at varied time lags. This study assists future modelling efforts in climate science.

Effects of Normothermic Conditioned Microwave Irradiation on Cultured Cells Using an Irradiation System with Semiconductor Oscillator and Thermo-regulatory Applicator

PubMed Central

Asano, Mamiko; Sakaguchi, Minoru; Tanaka, Satoshi; Kashimura, Keiichiro; Mitani, Tomohiko; Kawase, Masaya; Matsumura, Hitoshi; Yamaguchi, Takako; Fujita, Yoshikazu; Tabuse, Katsuyoshi

2017-01-01

We investigated the effects of microwave irradiation under normothermic conditions on cultured cells. For this study, we developed an irradiation system constituted with semiconductor microwave oscillator (2.45 GHz) and thermos-regulatory applicator, which could irradiate microwaves at varied output powers to maintain the temperature of cultured cells at 37 °C. Seven out of eight types of cultured cells were killed by microwave irradiation, where four were not affected by thermal treatment at 42.5 °C. Since the dielectric properties such as ε’, ε” and tanδ showed similar values at 2.45 GHz among cell types and media, the degree of microwave energy absorbed by cells might be almost the same among cell types. Thus, the vulnerability of cells to microwave irradiation might be different among cell types. In HL-60 cells, which were the most sensitive to microwave irradiation, the viability decreased as irradiation time and irradiation output increased; accordingly, the decrease in viability was correlated to an increase in total joule. However, when a high or low amount of joules per minute was supplied, the correlation between cellular viability and total joules became relatively weak. It is hypothesized that kinds of cancer cells are efficiently killed by respective specific output of microwave under normothermic cellular conditions. PMID:28145466

Irradiation and post-irradiation examination of uranium-free nitride fuel

NASA Astrophysics Data System (ADS)

Hania, P. R.; Klaassen, F. C.; Wernli, B.; Streit, M.; Restani, R.; Ingold, F.; Fedorov, A. V.; Wallenius, J.

2015-11-01

Two identical Phénix-type 15-15Ti steel pinlets each containing a 70 mm Pu0.3Zr0.7N fuel stack in a 1-bar helium atmosphere have been irradiated in the HFR Petten at medium high linear power (46-47 kW/m at BOL) and an average cladding temperature of 505 °C. The pins were irradiated to a plutonium burn-up of 9.7% (88 MWd/kgHM) in 170 full power days. Both pins remained fully intact. Post-irradiation examination performed at NRG and PSI showed that the overall swelling rate of the fuel was 0.92 vol-%/%FIHMA. Fission gas release was 5-6%, while helium release was larger than 50%. No fuel restructuring was observed, and only mild cracking. EPMA measurements show a burn-up increase toward the pellet edge of up to 4 times. All investigated fission products except to some extent the noble metals were found to be evenly distributed over the matrix, indicating good solubility. Local formation of a secondary phase with high Pu content and hardly any Zr was observed. A general conclusion of this investigation is that ZrN is a suitable inert matrix for burning plutonium at high destruction rates.

EFFECTS OF IN VITRO RADIOCOBALT IRRADIATION OF RABBIT OVA ON SUBSEQUENT DEVELOPMENT IN VIVO WITH SPECIAL REFERENCE TO THE IRRADIATION OF MATERNAL ORGANISM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, M.C.; Hunt, D.M.

Fertilized rabbit ova recovered one to six days after mating were irradiated in vitro from a radiocobalt source and then transplanted into recipient animals. When examined 22 to 28 days later 44, 33, 8 and 0% of ova irradiated respectively at 50, 100, 1,000 and 5,000 r developed into apparently normal fetuses without external or internal malformation. No significant differential sensitivity was apparent in ova irradiated at different ages. It was found further that 34, 36, 19 and 10% of two-, 4-, and 6-day ova irradiated respectively in vitro at 200, 400, 600, and 800 r developed into "normal" fetuses.more » Again no malformation of fetuses and no differential radiosensitivity between ova of different ages were observed. Following whole body irradiation at 400 r, it was found that 40% of non-irradiated ova developed into normal fetuses when transplanted into recipient animals that had been irradiated (vs. 36% in the irradiation of ova alone). However, only 17% of estimated ova developed into "normal" fetuses when pregnant rabbits were irradiated 2, 4 or 6 days after insemination (vs. 64% in the control). It appears that irradiation of the maternal organism influences embryonic development and that irradiation of pregnant animals exerts a combination of ill effects, on the ova and on their environment. Cytological study of irradiated blastocysts revealed no chromosomal breakage immediately after irradiation. Chromosomal abnormalities, fragmentation and condensation of chromatin were observed during the culture of irradiated blastocysts in accordance with the dosages applied. From this study it is concluded that (1) although 50 r may affect embryonic development, there seems to be no differential effect up to 400 r, above which greater prenatal death occurs; (2) before implantation, irradiated ova either die or develop into apparently normal fetuses and there is no evidence of differential radiosensitivity at various stages of development; (3) irradiation of the

Ultrastructural properties of laser-irradiated and heat-treated dentin.

PubMed

Rohanizadeh, R; LeGeros, R Z; Fan, D; Jean, A; Daculsi, G

1999-12-01

Previous studies using scanning electron microscopy and infrared absorption spectroscopy reported that laser irradiation causes compositional changes in enamel. The purpose of this study was to evaluate the ultrastructural and compositional changes in dentin caused by irradiation with a short-pulse laser (Q-switched Nd:YAG). The irradiated and non-irradiated areas of the lased dentin samples were investigated by scanning (SEM) and transmission electron microscopy (TEM), micro-micro electron diffraction, and electron microprobe analysis of dispersive energy (EDX). Heat-treated dentin was similarly investigated. This study demonstrated that laser irradiation resulted in the recrystallization of dentin apatite and in the formation of additional calcium phosphate phases consisting of magnesium-substituted beta-tricalcium phosphate, beta-TCMP, beta-(Ca,Mg)3(PO4)2, and tetracalcium phosphate, TetCP, Ca4(PO4)O. TEM analyses of the modified and unmodified zones of the irradiated areas showed two types of crystal populations: much larger crystals from the modified zone and crystals with size and morphology similar to those of dentin apatite in the unmodified zone. The morphology of crystals in the modified zones in the irradiated dentin resembled those of dentin sintered at 800 or 950 degrees C. In the irradiated areas (modified and unmodified zones), the Ca/P ratio was lower compared with that in the non-irradiated dentin. The Mg/Ca ratio in the modified zones was higher than that in the unmodified zones and in the non-irradiated dentin. In sintered dentin, the Mg/Ca ratio increased as a function of sintering temperature. The ultrastructural and compositional changes observed in laser-irradiated dentin may be attributed to high temperature and high pressure induced by microplasma during laser irradiation. These changes may alter the solubility of the irradiated dentin, making it less susceptible to acid dissolution or to the caries process.

Spectral solar UV irradiance data for cycle 21

NASA Astrophysics Data System (ADS)

DeLand, Matthew T.; Cebula, Richard P.

2001-10-01

The Nimbus 7 Solar Backscatter Ultraviolet (SBUV) instrument, which began taking data in November 1978, was the first instrument to make solar UV irradiance measurements covering both the minimum and maximum activity levels of a solar cycle. The currently archived irradiance data set was processed with an instrument characterization which fails to completely account for sensor degradation in the later part of the data record, thus limiting the accuracy of estimated long-term solar activity variations and the scientific value of the data. In this paper, we describe an improved Nimbus 7 SBUV spectral irradiance data set, which utilizes a more accurate model for instrument sensitivity and treats other time-dependent problems in the archived data. Estimated long-term irradiance changes during solar cycle 21 are 8.3(+/-2.6%) at 205 nm, and 4.9(+/-1.8)% at 240 nm. The revised Nimbus 7 SBUV irradiance data are in good agreement with predictions of solar cycle variations from the Mg II index proxy model. These solar irradiance changes are also consistent with overlapping irradiance data from the declining phase of solar cycle 21 measured by the Solar Mesosphere Explorer (SME). The Nimbus 7 SBUV irradiance data represent the earliest component of a 20+ year continuous record of solar spectral UV activity.

Luminescence properties after X-ray irradiation for dosimetry

NASA Astrophysics Data System (ADS)

Hong, Duk-Geun; Kim, Myung-Jin

2016-05-01

To investigate the luminescence characteristics after exposure to X-ray radiation, we developed an independent, small X-ray irradiation system comprising a Varian VF-50J mini X-ray generator, a Pb collimator, a delay shutter, and an Al absorber. With this system, the apparent dose rate increased linearly to 0.8 Gy/s against the emission current for a 50 kV anode potential when the shutter was delayed for an initial 4 s and the Al absorber was 300 µm thick. In addition, an approximately 20 mm diameter sample area was irradiated homogeneously with X rays. Based on three-dimensional (3D) thermoluminescence (TL) spectra, the small X-ray irradiator was considered comparable to the conventional 90Sr/90Y beta source even though the TL intensity from beta irradiation was higher than that from X-ray irradiation. The single aliquot regenerative (SAR) growth curve for the small X-ray irradiator was identical to that for the beta source. Therefore, we concluded that the characteristics of the small X-ray irradiator and the conventional 90Sr/90Y beta source were similar and that X ray irradiation had the potential for being suitable for use in luminescence dosimetry.

Identification of irradiated strawberries (in French)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deschreider, A.R.; Vigneron, J.M.

1973-01-01

From international colloquium: the identification of irradiated foodstuffs; Karlsruhe, Germany (24 0ct 1973). Packaged strawberries were irradiated with doses of 100, 200, and 500 krad of /sup 60/Co gamma rays. The irradiation of the fruit at these levels could not be detected either by measuring of the coloration of the anthocyanin extraction or the radioactivity of the phenylalanine-ammonia-lyase. If there is any plastic in the packaging material, examination under close infrared light reveals spectral modification when the dose level reaches 200 krad. (GE)

Comparison of irradiation behaviour of HTR graphite grades

NASA Astrophysics Data System (ADS)

Heijna, M. C. R.; de Groot, S.; Vreeling, J. A.

2017-08-01

The INNOGRAPH irradiations were executed in the High Flux Reactor (HFR) in Petten by NRG supported by the European Framework programs HTR-M, RAPHAEL, and ARCHER to generate data on the irradiation behaviour of graphite grades for High Temperature Reactor (HTR) application available at that time. Samples of the graphite grades NBG-10, NBG-17, NBG-18, NBG-20, NBG-25, PCEA, PPEA, PCIB, and IG-110 have been irradiated at 750 °C and 950 °C. The inherent scatter induced by the probabilistic material behaviour of graphite requires uncertainty and scatter induced by test conditions and post-irradiation examination to be minimized. The INNOGRAPH irradiations supplied an adequate number of irradiated samples to enable accurate determination of material properties and their evolution under irradiation. This allows comparison of different graphite grades and a qualitative assessment of their appropriateness for HTR applications, as a basis of selection, design and core component lifetime. The results indicate that coarse grained graphite grades exhibit more favourable behaviour for application in HTRs due to their low dimensional anisotropy and fracture propagation resilience.

Modelling rotational and cyclical spectral solar irradiance variations

NASA Astrophysics Data System (ADS)

Unruh, Yvonne

Solar irradiance changes are highly wavelength dependent: solar-cycle variations in the UV can be on the order of tens of percent, while changes in the visible are typically only of the order of one or two permille. With the launch of a number of instruments to measure spectral solar irradiance, we are now for a first time in a good position to explore the changing solar irradiance over a large range of wavelengths and to test our irradiance models as well as some of their underlying assumptions. I will introduce some of the current modelling approaches and present model-data comparisons, using the SATIRE irradiance model and SORCE/SIM measurements as an example. I will conclude by highlighting a number of outstanding questions regarding the modelling of spectral irradiance and current approaches to address these.

High accuracy diffuse horizontal irradiance measurements without a shadowband

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlemmer, J.A.; Michalsky, J.J.

1995-10-01

The standard method for measuring diffuse horizontal irradiance uses a fixed shadowband to block direct solar radiation. This method requires a correction for the excess skylight blocked by the band, and this correction varies with sky conditions. Alternately, diffuse horizontal irradiance may be calculated from the total horizontal and direct normal irradiance. This method is in error because of the angular (often referred to as cosine) response of the total horizontal pyranometer to direct beam irradiance. This paper describes an improved calculation of diffuse horizontal irradiance from total horizontal and direct normal irradiance using a predetermination of the angular responsemore » of the total horizontal pyranometer. The authors compare these diffuse horizontal irradiance calculations with measurements made with a shading-disk pyranometer that shields direct irradiance using a tracking disk. The results indicate significant improvement in most cases. The remaining disagreement most likely arises from undetected tracking errors and instrument leveling.« less

Understanding and simulating the material behavior during multi-particle irradiations

PubMed Central

Mir, Anamul H.; Toulemonde, M.; Jegou, C.; Miro, S.; Serruys, Y.; Bouffard, S.; Peuget, S.

2016-01-01

A number of studies have suggested that the irradiation behavior and damage processes occurring during sequential and simultaneous particle irradiations can significantly differ. Currently, there is no definite answer as to why and when such differences are seen. Additionally, the conventional multi-particle irradiation facilities cannot correctly reproduce the complex irradiation scenarios experienced in a number of environments like space and nuclear reactors. Therefore, a better understanding of multi-particle irradiation problems and possible alternatives are needed. This study shows ionization induced thermal spike and defect recovery during sequential and simultaneous ion irradiation of amorphous silica. The simultaneous irradiation scenario is shown to be equivalent to multiple small sequential irradiation scenarios containing latent damage formation and recovery mechanisms. The results highlight the absence of any new damage mechanism and time-space correlation between various damage events during simultaneous irradiation of amorphous silica. This offers a new and convenient way to simulate and understand complex multi-particle irradiation problems. PMID:27466040

Irradiation-induced phenomena in carbon nanomaterials

NASA Astrophysics Data System (ADS)

Krasheninnikov, Arkady

2008-03-01

The irradiation of solids with energetic particles such as electrons or ions is associated with disorder, normally an undesirable phenomenon. However, recent experiments [for an overview, see A.V Krasheninnikov, F. Banhart, Nature Materials, 6 (2007) 723] on bombardment of carbon nanostructures with energetic particles demonstrate that irradiation can have beneficial effects and that electron or ion beams may serve as tools to change the morphology and tailor mechanical, electronic and even magnetic properties of nanostructured carbon systems. We systematically study irradiation effects in carbon nanotubes and other forms of nano-structured carbon experimentally and theoretically by employing various atomistic models ranging from empirical potentials to time-dependent density functional theory. In my presentation, I will briefly review the recent progress in our understanding of ion-irradiation-induced phenomena in nano-structured carbon and present our recent theoretical [A.V Krasheninnikov, et al., Phys. Rev. Lett., 99 (2007) 016104, A. Tolvanen et al, Appl. Phys. Lett. 91 (2007) 173109.] and experimental [O. Lehtinen et al., to be published] results. I dwell on the ``beneficial'' role of defects and impurities in nanotubes and related systems. Finally, I will present the results of simulations of irradiation-induced pressure build-up inside nanotubes encapsulated with metals [L. Sun, et al., Science 312 (2006) 1199]. Electron irradiation of such composite systems in the transmission electron microscope gives rise to contraction of nanotube shells and thus to high pressure. The irradiation-stimulated pressure can be as high as 40 GPa, which makes it possible to study phase transformations at the nanoscale with high spatial resolution. I will also address the mechanisms of plastic deformation of small metal particles inside carbon shells at high temperatures, which may be important for understanding catalytic growth of carbon nanotubes.

The Role of DNA Methylation Changes in Radiation-Induced Bystander Effects in cranial irradiated Mice

NASA Astrophysics Data System (ADS)

Zhang, Meng; Sun, Yeqing; Xue, Bei; Wang, Xinwen; Wang, Jiawen

2016-07-01

Heavy-ion radiation could lead to bystander effect in neighboring non-hit cells by signals released from directly-irradiated cells. The exact mechanisms of radiation-induced bystander effect in distant organ remain obscure, yet accumulating evidence points to the role of DNA methylation changes in bystander effect. To identify the molecular mechanism that underlies bystander effects of heavy-ion radiation, the male Balb/c and C57BL mice were cranial exposed to 40, 200, 2000mGy dose of carbon heavy-ion radiation, while the rest of the animal body was shielded. The γH2AX foci as the DNA damage biomarker in directly irradiation organ ear and the distant organ liver were detected on 0, 1, 2, 6, 12 and 24h after radiation, respectively. Methylation-sensitive amplifcation polymorphism (MSAP) was used to monitor the level of polymorphic genomic DNA methylation changed with dose and time effects. The results show that cranial irradiated mice could induce the γH2AX foci and genomic DNA methylation changes significantly in both the directly irradiation organ ear and the distant organ liver. The percent of DNA methylation changes were time-dependent and tissue-specific. Demethylation polymorphism rate were highest separately at 1 h in 200 mGy and 6 h in 2000 mGy after irradiation in ear. The global DNA methylation changes tended to occur in the CG sites. We also found that the numbers of γH2AX foci and the genomic methylation changes of heavy-ion radiation-induced bystander effect in liver could be obvious 1 h after radiation and achieved the maximum at 6 h, while the changes could recover gradually at 12 h. The results suggest that mice head exposed to heavy-ion radiation can induce damage and methylation pattern changed in both directly radiation organ ear and distant organ liver. Moreover, our findings are important to understand the molecular mechanism of radiation induced bystander effects in vivo. Keywords: Heavy-ion radiation; Bystander effect; DNA methylation; γH2

Quality-of-life results for accelerated partial breast irradiation with interstitial brachytherapy versus whole-breast irradiation in early breast cancer after breast-conserving surgery (GEC-ESTRO): 5-year results of a randomised, phase 3 trial.

PubMed

Schäfer, Rebekka; Strnad, Vratislav; Polgár, Csaba; Uter, Wolfgang; Hildebrandt, Guido; Ott, Oliver J; Kauer-Dorner, Daniela; Knauerhase, Hellen; Major, Tibor; Lyczek, Jaroslaw; Guinot, Jose Luis; Dunst, Jürgen; Miguelez, Cristina Gutierrez; Slampa, Pavel; Allgäuer, Michael; Lössl, Kristina; Kovács, György; Fischedick, Arnt-René; Fietkau, Rainer; Resch, Alexandra; Kulik, Anna; Arribas, Leo; Niehoff, Peter; Guedea, Ferran; Schlamann, Annika; Gall, Christine; Polat, Bülent

2018-04-20

Previous results from the GEC-ESTRO trial showed that accelerated partial breast irradiation (APBI) using multicatheter brachytherapy in the treatment of early breast cancer after breast-conserving surgery was non-inferior to whole-breast irradiation in terms of local control and overall survival. Here, we present 5-year results of patient-reported quality of life. We did this randomised controlled phase 3 trial at 16 hospitals and medical centres in seven European countries. Patients aged 40 years or older with 0-IIA breast cancer were randomly assigned (1:1) after breast-conserving surgery (resection margins ≥2 mm) to receive either whole-breast irradiation of 50 Gy with a boost of 10 Gy or APBI using multicatheter brachytherapy. Randomisation was stratified by study centre, tumour type, and menopausal status, with a block size of ten and an automated dynamic algorithm. There was no masking of patients or investigators. The primary endpoint of the trial was ipsilateral local recurrence. Here, we present 5-year results of quality of life (a prespecified secondary endpoint). Quality-of-life questionnaires (European Organisation for Research and Treatment of Cancer QLQ-C30, breast cancer module QLQ-BR23) were completed before radiotherapy (baseline 1), immediately after radiotherapy (baseline 2), and during follow-up. We analysed the data according to treatment received (as-treated population). Recruitment was completed in 2009, and long-term follow-up is continuing. The trial is registered at ClinicalTrials.gov, number NCT00402519. Between April 20, 2004, and July 30, 2009, 633 patients had accelerated partial breast irradiation and 551 patients had whole-breast irradiation. Quality-of-life questionnaires at baseline 1 were available for 334 (53%) of 663 patients in the APBI group and 314 (57%) of 551 patients in the whole-breast irradiation group; the response rate was similar during follow-up. Global health status (range 0-100) was stable in both groups: at

Irradiation creep of various ferritic alloys irradiated at {approximately}400{degrees}C in the PFR and FFTF reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toloczko, M.B.; Garner, F.A.; Eiholzer, C.R.

1997-04-01

Three ferritic alloys were irradiated in two fast reactors to doses of 50 dpa or more at temperatures near 400{degrees}C. One martensitic alloy, HT9, was irradiated in both the FFTF and PFR reactors. PFR is the Prototype Fast Reactor in Dourneay, Scotland, and FFTF is the Fast Flux Test Facility in Richland, WA. D57 is a developmental alloy that was irradiated in PFR only, and MA957 is a Y{sub 2}O{sub 3} dispersion-hardened ferritic alloy that was irradiated only in FFTF. These alloys exhibited little or no void swelling at {approximately}400{degrees}C. Depending on the alloy starting condition, these steels develop amore » variety of non-creep strains early in the irradiation that are associated with phase changes. Each of these alloys creeps at a rate that is significantly lower than that of austenitic steels irradiated in the same experiments. The creep compliance for ferritic alloys in general appears to be {approximately}0.5 x 10{sup {minus}6} MPa{sup {minus}1} dpa{sup {minus}1}, independent of both composition and starting state. The addition of Y{sub 2}O{sub 3} as a dispersoid does not appear to change the creep behavior.« less

Research trends with food irradiation in Japan (in Japanese)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sato, T.

Potatoes and onions are irradiated to prevent their germination for 8 months after harvest. Twenty-seven tons of potatoes were exposed to /sup 60/Co gamma irradiation at a dose rate of 7 x 10/sup 4/ R/hr. Potatoes irradiated with a dose of 7 to 15 Krads were stored for 8 months at room temperature, and were suitable market produce. Sapporo yellow onions, produced in Hokkaido and which passed the year-end for storage, were mainly studied. It was possible to prevent germination of the onions if irradiated at a dose of 3 to 10 Krads within the dormant period. Concerning rice, itmore » was suggested that prevention of the main harmful insects of rice, such as rice weevil, Sordidus zeamais and Sordidus oryzal, was possible by sterilization and inactivation through irradiation at a dose of 15 Krads. The sterilization dose for harmful insects of wheat was 5 to 7 Krads. Theoff flavor in the wheat was recognized immediately after irradiation at a dose of 20 Krads, but after three months wheat did not show off flavor even with 50 Krads irradiation. As a result, the volume of bread was larger in irradiated bread rather than in nonirradiated bread. Vienna sausage without preservatives was irradiated in 500 Krads under the condition of being kept in cold storage at 10 deg C. Its decomposition was delayed one week. The proper dose for boiled fishpaste was determined to be 300 Krads, and its preservation period was prolonged from 7 to 10 days to 21 days by irradiation. In mandarin oranges, off flavor was caused by a dose level of 50 Krads of /sup 60/Co gamma radiation. Therefore, irradiation of mandarin oranges has to depend on electron irnadiation, but problems remain regarding the irradiation technique. In a study of the safety of irradiated food, potato irradiation was permitted by the Ministry of Health and Welfare at a dose of 15 Knads in August of 1972. Lastly, the condition of potato irradiation in the producing and consuming districts and economic problems are discussed

COBALT-60 Gamma Irradiation of Shrimp.

NASA Astrophysics Data System (ADS)

Sullivan, Nancy L. B.

Meta- and ortho-tyrosine were measured using high performance liquid chromatography (HPLC) in conjunction with electrochemical detection in shrimp irradiated using cobalt-60 gamma radiation in the absorbed dose range 0.8 to 6.0 kGy, in nonirradiated shrimp, and in bovine serum albumin (BSA) irradiated in dilute aqueous solution at 25.0 kGy. Ortho-tyrosine was measured in nonirradiated BSA. Para-, meta-, and ortho-tyrosine were measured using HPLC in conjunction with uv-absorption detection in dilute aqueous solutions of phenylalanine irradiated in the absorbed dose range 16.0 to 195.0 kGy. The measured yields of tyrosine isomers were approximately linear as a function of absorbed dose in shrimp, and in irradiated solutions of phenylalanine up to 37.0 kGy. The occurrence of meta- and ortho-tyrosine, which had formerly been considered unique radiolytic products, has not previously been reported in nonirradiated shrimp or BSA. The conventional hydrolyzation and analytical techniques used in the present study to measure meta- and ortho-tyrosine may provide the basis for a method to detect and determine the dose used in food irradiation.

Irradiation of municipal sludge for agricultural use

NASA Astrophysics Data System (ADS)

Ahlstrom, Scott B.

Research has demonstrated that irradiation is an effective means for reducing pathogens in sewage sludge to levels where sludge reuse in public areas meets criteria for protection of the public health. Complementary research has demonstrated the value of the irradiated sludge in both agronomic and animal science applications. The benefits of sludge application to cropland are well documented. The irradiation process does not increase the extractability and plant uptake of a broad range of nutrients and heavy metals from sludge-amended soils. However, it does eliminate the hazards associated with pathogen contamination when applying sludge to agricultural land. Irradiated sludge has also been evaluated as a supplemental foodstuff for cattle and sheep. The data indicate that products derived from raw sewage may have a substantial nutritive value for ruminant animals. Irradiation of sewage sludge is a practical means of sludge disinfection. Where a highly disinfected sludge is required, it should be considered as a viable sludge management alternative. Evaluation of sludge irradiation technology and its associated costs must be done with consideration of other sludge treatment processes to develop an acceptable sludge management system.

Microbiological decontamination of natural honey by irradiation

NASA Astrophysics Data System (ADS)

Migdał, W.; Owczarczyk, H. B.; K ȩdzia, B.; Hołderna-K ȩdzia, E.; Madajczyk, D.

2000-03-01

Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator "Elektronika 10-10" at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

Effects of alpha-lipoic acid on associative and spatial memory of sham-irradiated and 56Fe-irradiated C57BL/6J male mice.

PubMed

Villasana, Laura E; Rosenthal, Rosalind A; Doctrow, Susan R; Pfankuch, Timothy; Zuloaga, Damian G; Garfinkel, Alexandra Maccoll; Raber, Jacob

2013-01-01

Cranial irradiation with (56)Fe, a form of space radiation, causes hippocampus-dependent cognitive changes. (56)Fe irradiation also increases reactive oxygen species (ROS) levels, which may contribute to these changes. Therefore, we investigated the effects of the antioxidant alpha lipoic acid (ALA) on cognition following sham-irradiation and irradiation. Male mice were irradiated (brain only) with (56)Fe (3 Gy) or sham-irradiated at 6-9 months of age. Half of the mice remained fed a regular chow and the other half of the mice were fed a caloric-matched diet containing ALA starting two-weeks prior to irradiation and throughout cognitive testing. Following cognitive testing, levels of 3-nitrotyrosine (3NT), a marker of oxidative protein stress, and levels of microtubule-associated protein (MAP-2), a dendritic protein important for cognition, were assessed using immunohistochemistry and confocal microscopy. ALA prevented radiation-induced impairments in spatial memory retention in the hippocampal and cortical dependent water maze probe trials following reversal learning. However, in sham-irradiated mice, ALA treatment impaired cortical-dependent novel object recognition and amygdala-dependent cued fear conditioning. There was a trend towards lower 3NT levels in irradiated mice receiving a diet containing ALA than irradiated mice receiving a regular diet. In the hippocampal dentate gyrus of mice on regular diet, irradiated mice had higher levels of MAP-2 immunoreactivity than sham-irradiated mice. Thus, ALA might have differential effects on the brain under normal physiological conditions and those involving environmental challenges such as cranial irradiation. Copyright © 2012 Elsevier Inc. All rights reserved.

Re-crystallization of ITO films after carbon irradiation

NASA Astrophysics Data System (ADS)

Usman, Muhammad; Khan, Shahid; Khan, Majid; Abbas, Turab Ali

2017-01-01

2.0 MeV carbon ion irradiation effects on Indium Tin Oxide (ITO) thin films on glass substrate are investigated. The films are irradiated with carbon ions in the fluence range of 1 × 1013 to 1 × 1015 ions/cm2. The irradiation induced effects in ITO are compared before and after ion bombardment by systematic study of structural, optical and electrical properties of the films. The XRD results show polycrystalline nature of un-irradiated ITO films which turns to amorphous state after 1 × 1013 ions/cm2 fluence of carbon ions. Further increase in ion fluence to 1 × 1014 ions/cm2 re-crystallizes the structure and retains for even higher fluences. A gradual decrease in the electrical conductivity and transmittance of irradiated samples is observed with increasing ion fluence. The band gap of the films is observed to be decreased after carbon irradiation.

Post-irradiation examinations of Li 4SiO 4 pebbles irradiated in the EXOTIC-7 experiment

NASA Astrophysics Data System (ADS)

Piazza, G.; Scaffidi-Argentina, F.; Werle, H.

2000-12-01

Extraction of tritium in ceramics-7 (EXOTIC-7) was the first in-pile test with 6Li-enriched (50%) lithium orthosilicate (Li 4SiO 4) pebbles and with DEMO representative Li-burnup. Post-irradiation examinations (PIEs) of the Li 4SiO 4 have been performed at the Forschungszentrum Karlsruhe (FZK) to investigate the tritium release kinetics, the effects of Li-burnup, of the contact with beryllium during irradiation and the changes in the mechanical stability of the pebbles due to irradiation. Based on these data one can conclude that neither the contact with beryllium nor a burnup up to 13% have a detrimental effect on the tritium release of Li 4SiO 4 pebbles, but at 18% Li-burnup the residence time is increased by about a factor of 3. The mechanical strength of both irradiated and unirradiated pebbles has been examined by means of crush tests. According to the PIE no significant changes in the mechanical stability of the pebbles have been observed.

Assessment of global solar radiation to examine the best locations to install a PV system in Tunisia

NASA Astrophysics Data System (ADS)

Belkilani, Kaouther; Ben Othman, Afef; Besbes, Mongi

2018-02-01

The study of the solar radiation is the starting point of any investigation for a new energy, to study and search the best location to install a PV system. A very important factor in the assessment of solar potential is the availability of data for global solar radiation that must be coherent and of high quality. In this paper, we analyze the estimation result of the monthly global solar radiation for three different locations, Bizerte in Northern Tunisia, Kairouan in Middle Eastern Tunisia, and Tozeur in Southern Tunisia, measured on the surface by the National Institute of Meteorology and the meteorological year irradiation based on satellite imagery result PVGIS radiation databases. To get the right measurements with minimum error, we propose a numerical model used to calculate the global solar radiation in the indicated three sites. The results show that the model can estimate the global solar radiation (kWh/m²) at a specific station and over most area of Tunisia. The model gives a good estimation for solar radiation where error between the measured values and those calculated are negligible.

10 GY TOTAL BODY IRRADIATION INCREASES RISK OF CORONARY SCLEROSIS, DEGENERATION OF HEART STRUCTURE AND FUNCTION IN A RAT MODEL

PubMed Central

Baker, John E; Fish, Brian L; Su, Jidong; Haworth, Steven T; Strande, Jennifer L; Komorowski, Richard A; Migrino, Raymond Q; Doppalapudi, Anil; Harmann, Leanne; Li, X Allen; Hopewell, John W; Moulder, John E

2009-01-01

Purpose To determine the impact of 10 Gy total body irradiation (TBI) or local thorax irradiation, a dose relevant to a radiological terrorist threat, on lipid and liver profile, coronary microvasculature and ventricular function. Materials and methods WAG/RijCmcr rats received 10 Gy TBI followed by bone marrow transplantation, or 10 Gy local thorax irradiation. Age-matched, non-irradiated rats served as controls. The lipid profile and liver enzymes, coronary vessel morphology, nitric oxide synthase (NOS) isoforms, protease activated receptor (PAR)-1 expression and fibrinogen levels were compared. Two dimensional strain echocardiography assessed global radial and circumferential strain on the heart. Results TBI resulted in a sustained increase in total and low density lipoprotein (LDL) cholesterol (190±8 vs. 58±6; 82±8 vs. 13±3 mg/dL, respectively). The density of small coronary arterioles was decreased by 32%. Histology revealed complete blockage of some vessels while cardiomyocytes remained normal. TBI resulted in cellular peri-arterial fibrosis whereas control hearts had symmetrical penetrating vessels with less collagen and fibroblasts. TBI resulted in a 32±4% and 28±3% decrease in endothelial NOS and inducible NOS protein respectively, and a 21±4% and 35±5% increase in fibrinogen and PAR-1 protein respectively, after 120 days. TBI reduced radial strain (19±8 vs. 46±7%) and circumferential strain (-8±3 vs. −15±3%) compared to controls. Thorax-only irradiation produced no changes over the same time frame. Conclusions TBI with 10 Gy, a dose relevant to radiological terrorist threats, worsened lipid profile, injured coronary microvasculature, altered endothelial physiology and myocardial mechanics. These changes were not manifest with local thorax irradiation. Non-thoracic circulating factors may be promoting radiation-induced injury to the heart. PMID:19995235

Effect of gamma irradiation on the photoluminescence of porous silicon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elistratova, M. A., E-mail: Marina.Elistratova@mail.ioffe.ru; Romanov, N. M.; Goryachev, D. N.

The effect of gamma irradiation on the luminescence properties of porous silicon produced by the electrochemical technique is studied. Changes in the photoluminescence intensity between irradiation doses and over a period of several days after the last irradiation are recorded. The quenching of photoluminescence at low irradiation doses and recovery after further irradiation are registered. It is found that porous silicon is strongly oxidized after gamma irradiation and the oxidation process continues for several days after irradiation. It is conceived that the change in the photoluminescence spectra and intensity of porous silicon after gamma irradiation is caused by a changemore » in the passivation type of the porous surface: instead of hydrogen passivation, more stable oxygen passivation is observed. To stabilize the photoluminescence spectra of porous silicon, the use of fullerenes is proposed. No considerable changes in the photoluminescence spectra during irradiation and up to 18 days after irradiation are detected in a porous silicon sample with a thermally deposited fullerene layer. It is shown that porous silicon samples with a deposited C{sub 60} layer are stable to gamma irradiation and oxidation.« less

Health protection and food preservation by gamma irradiation

NASA Technical Reports Server (NTRS)

1976-01-01

Results of several major studies on food systems for space missions beginning with Apollo 12 through Apollo-Soyuz and investigations of the application of irradiation to food for manned space flight are reported. The study of flight food systems involved the application of radurization (pasteurizing levels) doses of gamma irradiation to flour and bread supplied by Pepperidge Farms in advance of the missions. All flights from Apollo 12 through 17 carried irradiated fresh bread. On Apollo 17, cooperation with Natick Laboratories permitted the introduction of a ham sandwich using irradiated bread and irradiated sterile ham. Investigations centered on irradiated bread were conducted during the course of these missions. Studies were applied to the concept of improving fresh bread from the point of view of mold inhibition. The studies considered how irradiation could best be applied at what levels and on a variety of bread types. Throughout the studies of the application of gamma irradiation the emphasis was placed upon using low levels of irradiation in the pasteurizing or radurizing doses--under a Megarad. The primary goal was to determine if a public health benefit could be demonstrated using radurization along with food preservation and food quality improvements. The public health benefit would be parallel to that of pasteurization of milk as a concept. Publications are included providing the details of these observations, one dealing with the flour characteristics and the other dealing with the influence on fresh bread types. These demonstrate the major findings noted during the period of the studies examining bread.

Internal contamination of an irradiator discovered during security enhancement.

PubMed

Harvey, R P

2014-08-01

High-risk radioactive sources regulated under Increased Controls Regulations have been protected by licensed facilities, but the federal government has placed significant emphasis on these sources and has developed initiatives to assist radioactive material licensees. The Department of Energy's Global Threat Reduction Initiative (GTRI) Domestic Threat Reduction Program is a voluntary federally funded program for security enhancements of high-risk radiological material. During the hardening or security enhancement process by the United States Department of Energy (U.S. DOE) contractors, a small amount of radioactive contamination was discovered in a Cesium irradiator. Ultimately, it was decided to pursue disposal with U.S. DOE's Off-Site Recovery Program (OSRP). Radiological devices may have a leaking source or known internal contamination that may cause difficulty during security enhancement. If the licensee understands this, it may provide facilities the opportunity to plan and prepare for unusual circumstances.

[Effect of electromagnetic pulse irradiation on mice reproduction].

PubMed

Wang, Shui-ming; Wang, De-wen; Peng, Rui-yun; Chen, Hao-yu; Gao, Ya-bing; Cao, Xiao-zhe; Cui, Xue-mei; Zhao, Mei-lan

2003-10-01

To evaluate the effect of electromagnetic pulse (EMP) irradiation on mice reproduction. Female/male Kunming mice, 6 - 8 weeks old, prior to mating, or female after pregnancy were treated with whole body irradiation by 6 x 10(4) V/m electromagnetic pulse (EMP) for five times. The pregnant mice were killed on the 18th days, and teratological markers were analysed. EMP irradiation caused no significant changes in most of female organ weight and organ/body weight ratio. But it caused significant shortening in tail length of live foetus in the female mice before conception (prior to mating) or after pregnancy (P < 0.05), and obvious decrease in male offspring ratio (0.85 +/- 0.09 vs 1.09 +/- 0.17, P < 0.05). The male offspring ratio also significantly decreased (0.76 +/- 0.18 vs 1.09 +/- 0.17, P < 0.01) after male mice irradiated by EMP. The tail length of live foetus was shortened and male offspring sex ratio was increased after both male and female mice were irradiated by EMP. EMP irradiation also caused a significantly higher fetal death rate than normal control (P < 0.05). The embryo absorption rate was increased after irradiation except that was decreased in male mice. EMP irradiation has effect on pregnancy and offspring development in both male and female mice before mating and in female mice after pregnancy.

Randomized study of whole-abdomen irradiation versus pelvic irradiation plus cyclophosphamide in treatment of early ovarian cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sell, A.; Bertelsen, K.; Andersen, J.E.

From 1 September 1981 to 1 January 1987, 118 patients with FIGO Stage IB, IC, IIA, IIB, and IIC epithelial ovarian cancer were randomized to abdominal irradiation or pelvic irradiation + cyclophosphamide. There was no difference between the regimens with respect to recurrence-free survival (55%) and 4-year overall survival (63%). At routine second-look laparotomy, 16% of patients without clinical detectable tumor showed recurrence. Twenty-five percent of the patients treated with pelvic irradiation + cyclophosphamide had hemorrhagic cystitis, probably caused by radiation damage and cyclophosphamide cystitis. Eight percent had late gastrointestinal symptoms requiring surgery.

EFFECTS OF CHRONIC IRRADIATION ON EINKORN WHEAT (in Japanese)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsumura, S.; Fujii, T.

1963-01-01

An experiment was carried out with seedlings of einkorn wheat ( Triticum monococcum flavescens), planted at the stage of 3 to 4 foilage leaves on Feb 23rd at several distances from the source and irradiated with varying dose rates and dosages. The plants wer irradiated during their growth and harvested on June 21st. Regular irradiation followed the routine of the gamma field; that is it was applied 20 hr per day starting from April 1st, but before that time, irradiation was occasionally given for mearsurement of dosage or dose rates and checks of the apparatus. Therefore, total irradiation time frommore » planting to harvest amounted to 1843 hours. Total dosages were calculated as 369 r minimum and 4608 r maximum, intensity being 4 to 50 r/20 hr. Survival rate clearly decreased at the highest dosage, while there was no marked difference between the other five irradiated lots and the nonirradiated one. On the other hand, seed fertility was nonlinearly (gradually at higher dosages) decreased with increasing dosage and reached to about one-half of that of the control lot at the highest dosage. For comparison, seedlings of the same kind were irradiated by 0.5 and 1 kr acute gamma rays (1 kr/hr) 16 days after sowing. Survival rate and fertility markedly decreased at 1-kr irradiation. The results were not easily comparable with those of chronic irradiation because acute irradiation was done only in the early seedling stage. Acute 1-kr irradiation showed severe effects and a similar effect was seen at the highest dosage of chronic irradiation (4607 r). Thus, the plants must be more tolerant to higher dosage when radiation intensity is low. (P.C.H.)« less

Structural responses of metallic glasses under neutron irradiation.

PubMed

Yang, L; Li, H Y; Wang, P W; Wu, S Y; Guo, G Q; Liao, B; Guo, Q L; Fan, X Q; Huang, P; Lou, H B; Guo, F M; Zeng, Q S; Sun, T; Ren, Y; Chen, L Y

2017-12-01

Seeking nuclear materials that possess a high resistance to particle irradiation damage is a long-standing issue. Permanent defects, induced by irradiation, are primary structural changes, the accumulation of which will lead to structural damage and performance degradation in crystalline materials served in nuclear plants. In this work, structural responses of neutron irradiation in metallic glasses (MGs) have been investigated by making a series of experimental measurements, coupled with simulations in ZrCu amorphous alloys. It is found that, compared with crystalline alloys, MGs have some specific structural responses to neutron irradiation. Although neutron irradiation can induce transient vacancy-like defects in MGs, they are fully annihilated after structural relaxation by rearrangement of free volumes. In addition, the rearrangement of free volumes depends strongly on constituent elements. In particular, the change in free volumes occurs around the Zr atoms, rather than the Cu centers. This implies that there is a feasible strategy for identifying glassy materials with high structural stability against neutron irradiation by tailoring the microstructures, the systems, or the compositions in alloys. This work will shed light on the development of materials with high irradiation resistance.

Facilities for studing radiation damage in nonmetals during irradiation

NASA Astrophysics Data System (ADS)

Levy, P. W.

1984-08-01

Two facilities were developed for making optical absorption, luminescence and other measurements on a single sample before, during and after irradiation. One facility uses Co-60 gamma rays and the other 0.5 to 3 MeV electrons from an accelerator. Optical relays function as spectrophotometers, luminescence detectors, etc. All radiation sensitive components are outside of walk-in irradiation chambers; all measurement control and data recording is computerized. Irradiations are made at controlled temperatures between 5 K and 900 C. The materials studied include glasses, quartz, alkali halides (especially natural rock salt), organic crystals, etc. As determined from color center measurements the damage formation rate in all materials studied at 25 C or above is strongly temperature dependent. The defect concentration during irradiation is usually much greater than that measured after irradiation. The fraction of defects annealing after irradiation and the annealing rate usually increases as the irradiation temperature increases. The completed studies demonstrate that, in most cases, the extent of maximum damage and the damage formation and annealing kinetics can be determined only by making measurements during irradiation.

Dose controlled low energy electron irradiator for biomolecular films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumar, S. V. K., E-mail: svkk@tifr.res.in; Tare, Satej T.; Upalekar, Yogesh V.

2016-03-15

We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at −20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface weremore » developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.« less

Diamond structure recovery during ion irradiation at elevated temperatures

NASA Astrophysics Data System (ADS)

Deslandes, Alec; Guenette, Mathew C.; Belay, Kidane; Elliman, Robert G.; Karatchevtseva, Inna; Thomsen, Lars; Riley, Daniel P.; Lumpkin, Gregory R.

2015-12-01

CVD diamond is irradiated by 5 MeV carbon ions, with each sample held at a different temperature (300-873 K) during irradiations. The defect structures resulting from the irradiations are evident as vacancy, interstitial and amorphous carbon signals in Raman spectra. The observed variation of the full width at half maximum (FWHM) and peak position of the diamond peak suggests that disorder in the diamond lattice is reduced for high temperature irradiations. The dumbbell interstitial signal is reduced for irradiations at 873 K, which suggests this defect is unstable at these temperatures and that interstitials have migrated to crystal surfaces. Near edge X-ray absorption fine structure (NEXAFS) spectroscopy results indicate that damage to the diamond structure at the surface has occurred for room temperature irradiations, however, this structure is at least partially recovered for irradiations performed at 473 K and above. The results suggest that, in a high temperature irradiation environment such as a nuclear fusion device, in situ annealing of radiation-created defects can maintain the diamond structure and prolong the lifetime of diamond components.

Regulation of tomato fruit ascorbate content is more highly dependent on fruit irradiance than leaf irradiance.

PubMed

Gautier, Hélène; Massot, Capucine; Stevens, Rebecca; Sérino, Sylvie; Génard, Michel

2009-02-01

The mechanisms involving light control of vitamin C content in fruits are not yet fully understood. The present study aimed to evaluate the impact of fruit and leaf shading on ascorbate (AsA) accumulation in tomato fruit and to determine how fruit sugar content (as an AsA precursor) affected AsA content. Cherry tomato plants were grown in a glasshouse. The control treatment (normally irradiated fruits and irradiated leaves) was compared with the whole-plant shading treatment and with leaf or fruit shading treatments in fruits harvested at breaker stage. In a second experiment, the correlation between sugars and AsA was studied during ripening. Fruit shading was the most effective treatment in reducing fruit AsA content. Under normal conditions, AsA and sugar content were correlated and increased with the ripening stage. Reducing fruit irradiance strongly decreased the reduced AsA content (-74 %), without affecting sugars, so that sugar and reduced AsA were no longer correlated. Leaf shading delayed fruit ripening: it increased the accumulation of oxidized AsA in green fruits (+98 %), whereas it decreased the reduced AsA content in orange fruits (-19 %), suggesting that fruit AsA metabolism also depends on leaf irradiance. Under fruit shading only, the absence of a correlation between sugars and reduced AsA content indicated that fruit AsA content was not limited by leaf photosynthesis or sugar substrate, but strongly depended on fruit irradiance. Leaf shading most probably affected fruit AsA content by delaying fruit ripening, and suggested a complex regulation of AsA metabolism which depends on both fruit and leaf irradiance and fruit ripening stage.

Infrared Irradiation: Toward Green Chemistry, a Review.

PubMed

Escobedo, René; Miranda, René; Martínez, Joel

2016-03-26

This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included.

Infrared Irradiation: Toward Green Chemistry, a Review

PubMed Central

Escobedo, René; Miranda, René; Martínez, Joel

2016-01-01

This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included. PMID:27023535

[Identification of irradiated abalone by ESR spectroscopy].

PubMed

Song, Yeping; Wang, Chuanxian; Yang, Zhenyu; Zhong, Weike; Geng, Jinpei; Lu, Di; Ding, Zhuoping

2012-05-01

To establish an analytical method for the detection and identification of irradiated abalone by electron spin resonance spectroscopy. Electron spin resonance (ESR) was used to study the spectral characteristics of abalone and the characteristic peak for quantitation. There were obvious different ESR spectra between unirradiated and irradiated abalone. The g factor for unirradiated abalone was 2.0055-2.0060, the g1 and g2 factor for irradiated abalone were (2.0027 +/- 0.0001) and (1.9994 +/- 0.0001), respectively. The ESR signal intensity of characteristic peak was positively correlated with absorbed dose in the range of 0.5 - 10 kGy, left peak was the characteristic peak for quantitation and the detection limit was < or = 0.5 kGy. It was difficult to quantitate when the absorbed dose was over 10 kGy. ESR characteristic peak and g factor were able to qualitatively determine the irradiation of abalone. ESR spectroscopy is an effective method to determine whether the abalone being irradiated or not.

Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33 secreted from impaired vessels in the skin compared to fractionated irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Eun-Jung, E-mail: forejs2@yuhs.ac; Kim, Jun Won, E-mail: JUNWON@yuhs.ac; Yoo, Hyun, E-mail: gochunghee@yuhs.ac

We have revealed in a porcine skin injury model that eosinophil recruitment was dose-dependently enhanced by a single high-dose irradiation. In this study, we investigated the underlying mechanism of eosinophil-associated skin fibrosis and the effect of high-dose-per-fraction radiation. The dorsal skin of a mini-pig was divided into two sections containing 4-cm{sup 2} fields that were irradiated with 30 Gy in a single fraction or 5 fractions and biopsied regularly over 14 weeks. Eosinophil-related Th2 cytokines such as interleukin (IL)-4, IL-5, and C–C motif chemokine-11 (CCL11/eotaxin) were evaluated by quantitative real-time PCR. RNA-sequencing using 30 Gy-irradiated mouse skin and functional assays in amore » co-culture system of THP-1 and irradiated-human umbilical vein endothelial cells (HUVECs) were performed to investigate the mechanism of eosinophil-mediated radiation fibrosis. Single high-dose-per-fraction irradiation caused pronounced eosinophil accumulation, increased profibrotic factors collagen and transforming growth factor-β, enhanced production of eosinophil-related cytokines including IL-4, IL-5, CCL11, IL-13, and IL-33, and reduced vessels compared with 5-fraction irradiation. IL-33 notably increased in pig and mouse skin vessels after single high-dose irradiation of 30 Gy, as well as in irradiated HUVECs following 12 Gy. Blocking IL-33 suppressed the migration ability of THP-1 cells and cytokine secretion in a co-culture system of THP-1 cells and irradiated HUVECs. Hence, high-dose-per-fraction irradiation appears to enhance eosinophil-mediated fibrotic responses, and IL-33 may be a key molecule operating in eosinophil-mediated fibrosis in high-dose-per fraction irradiated skin. - Highlights: • Single high-dose irradiation aggravates eosinophil-mediated fibrosis through IL-33. • Vascular endothelial cells damaged by high-dose radiation secrete IL-33. • Blocking IL-33 suppressed migration of inflammatory cells and cytokine secretion

Comparison of magnetic properties of austenitic stainless steel after ion irradiation

NASA Astrophysics Data System (ADS)

Xu, Chaoliang; Liu, Xiangbing; Xue, Fei; Li, Yuanfei; Qian, Wangjie

2018-07-01

Specimens of austenitic stainless steel (ASS) were irradiated with H, Fe and Xe ions at room temperature. The vibrating sample magnetometer (VSM) and grazing incidence X-ray diffraction (GIXRD) were used to analyze the magnetic properties and martensite formation. The magnetic hysteresis loops indicated that higher irradiation damage causes more significant magnetization phenomenon. Under the same damage level, Xe irradiation causes the most significant magnetization, Fe irradiation is the second, and H irradiation is the least. A similar martensite amount variation with irradiation can be obtained. The coercivity Hc increases first to 2 dpa and then decreases continuously with irradiation damage for Xe irradiation. At the same damage lever, H irradiation causes a largest Hc and Xe irradiation causes a minimal one.

EFFECT OF $gamma$-RAY IRRADIATION ON RED SEAWEEDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katsuura, K.; Suzuki, S.; Okano, T.

1962-07-01

The influence of gamma irradiation on chemical composition and physical properties, especially on jelly-forming ability, of red seaweeds (Rhodophyceae) was studied. Kirinsai (Eucheuma spinosum) and Ogonori (Gracilaria confervoides) were used as the samples of red seaweeds, and the raw seaweeds and the extracted mucilage from Kirinsai were irradiated by Co/sup 60/ gamma rays at doses ranging from 10/sup 4/ to 10/sup 7/ r After irradiation the relations between irradiation dosage and jelly strength, viscosity, and sulfate and carboxyl group content of the mucilage were examined. It was observed that irradiation did not increase jelly strength owing to the de-esterification ofmore » sulfate group, but it led to degradation of the main chain. From the results of fractionation experiments and the decrease of carboxyl group by irradiation, it was concluded that Kirinsai consists of the various kinds of polysaccharide and is not a polymer of a single component such as is true of Ogonori mucilage. (H.H.D.)« less

Reconstruction of solar spectral irradiance since the Maunder minimum

NASA Astrophysics Data System (ADS)

Krivova, N. A.; Vieira, L. E. A.; Solanki, S. K.

2010-12-01

Solar irradiance is the main external driver of the Earth's climate. Whereas the total solar irradiance is the main source of energy input into the climate system, solar UV irradiance exerts control over chemical and physical processes in the Earth's upper atmosphere. The time series of accurate irradiance measurements are, however, relatively short and limit the assessment of the solar contribution to the climate change. Here we reconstruct solar total and spectral irradiance in the range 115-160,000 nm since 1610. The evolution of the solar photospheric magnetic flux, which is a central input to the model, is appraised from the historical record of the sunspot number using a simple but consistent physical model. The model predicts an increase of 1.25 W/m2, or about 0.09%, in the 11-year averaged solar total irradiance since the Maunder minimum. Also, irradiance in individual spectral intervals has generally increased during the past four centuries, the magnitude of the trend being higher toward shorter wavelengths. In particular, the 11-year averaged Ly-α irradiance has increased by almost 50%. An exception is the spectral interval between about 1500 and 2500 nm, where irradiance has slightly decreased (by about 0.02%).

Void growth and coalescence in irradiated copper under deformation

NASA Astrophysics Data System (ADS)

Barrioz, P. O.; Hure, J.; Tanguy, B.

2018-04-01

A decrease of fracture toughness of irradiated materials is usually observed, as reported for austenitic stainless steels in Light Water Reactors (LWRs) or copper alloys for fusion applications. For a wide range of applications (e.g. structural steels irradiated at low homologous temperature), void growth and coalescence fracture mechanism has been shown to be still predominant. As a consequence, a comprehensive study of the effects of irradiation-induced hardening mechanisms on void growth and coalescence in irradiated materials is required. The effects of irradiation on ductile fracture mechanisms - void growth to coalescence - are assessed in this study based on model experiments. Pure copper thin tensile samples have been irradiated with protons up to 0.01 dpa. Micron-scale holes drilled through the thickness of these samples subjected to uniaxial loading conditions allow a detailed description of void growth and coalescence. In this study, experimental data show that physical mechanisms of micron-scale void growth and coalescence are similar between the unirradiated and irradiated copper. However, an acceleration of void growth is observed in the later case, resulting in earlier coalescence, which is consistent with the decrease of fracture toughness reported in irradiated materials. These results are qualitatively reproduced with numerical simulations accounting for irradiation macroscopic hardening and decrease of strain-hardening capability.

Irradiation enhancement of biomass conversion

NASA Astrophysics Data System (ADS)

Smith, G. S.; Kiesling, H. E.; Galyean, M. L.; Bader, J. R.

The vast supply of cellulosic agricultural residues and industrial by-products that is produced each year is a prospective resource of biomass suitable for conversion to useful products such as feedstock for the chemicals industry and feedstuffs for the livestock industry. Conversions of such biomass is poor at present, and utilization is inefficient, because of physio-chemical barriers to biological degradation and (or) anti-quality components such as toxicants that restrict biological usages. Improvements in biodegradability of ligno-cellulosic materials have been accomplished by gamma-ray and electron-beam irradiation at intermediate dosage (˜ 50 Mrad; .5 MGy); but applications of the technology have been hampered by questionable interpretations of results. Recent research with organic wastes such as sewage sludge and straw suggests opportunity for important applications of irradiation technology in enhancement of biomass conversion. Data from experiments using irradiated straw as feed for ruminants are presented and discussed in relation to research on prospective usage of sewage products as feed for ruminants. Findings are discussed in regard to prospective applications in industrial fermentation processes. Possible usage of irradiation technology for destruction of toxicants in exotic plants is considered in regard to prospective new feedstuffs.

A Practical Irradiance Model for Bifacial PV Modules: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marion, Bill; MacAlpine, Sara; Deline, Chris

2017-06-15

A model, suitable for a row or multiple rows of photovoltaic (PV) modules, is presented for estimating the backside irradiance for bifacial PV modules. The model, which includes the effects of shading by the PV rows, is based on the use of configuration factors (CFs) to determine the fraction of a source of irradiance that is received by the backside of the PV module. Backside irradiances are modeled along the sloped height of the PV module, but assumed not to vary along the length of the PV row. The backside irradiances are corrected for angle-of-incidence losses and may be addedmore » to the front side irradiance to determine the total irradiance resource for the PV cell. Model results are compared with the measured backside irradiances for NREL and Sandia PV systems, and with results when using the RADIANCE ray tracing program.« less

NSUF Irradiated Materials Library

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cole, James Irvin

The Nuclear Science User Facilities has been in the process of establishing an innovative Irradiated Materials Library concept for maximizing the value of previous and on-going materials and nuclear fuels irradiation test campaigns, including utilization of real-world components retrieved from current and decommissioned reactors. When the ATR national scientific user facility was established in 2007 one of the goals of the program was to establish a library of irradiated samples for users to access and conduct research through competitively reviewed proposal process. As part of the initial effort, staff at the user facility identified legacy materials from previous programs thatmore » are still being stored in laboratories and hot-cell facilities at the INL. In addition other materials of interest were identified that are being stored outside the INL that the current owners have volunteered to enter into the library. Finally, over the course of the last several years, the ATR NSUF has irradiated more than 3500 specimens as part of NSUF competitively awarded research projects. The Logistics of managing this large inventory of highly radioactive poses unique challenges. This document will describe materials in the library, outline the policy for accessing these materials and put forth a strategy for making new additions to the library as well as establishing guidelines for minimum pedigree needed to be included in the library to limit the amount of material stored indefinitely without identified value.« less

Focal brain lesions induced with ultraviolet irradiation.

PubMed

Nakata, Mariko; Nagasaka, Kazuaki; Shimoda, Masayuki; Takashima, Ichiro; Yamamoto, Shinya

2018-05-22

Lesion and inactivation methods have played important roles in neuroscience studies. However, traditional techniques for creating a brain lesion are highly invasive, and control of lesion size and shape using these techniques is not easy. Here, we developed a novel method for creating a lesion on the cortical surface via 365 nm ultraviolet (UV) irradiation without breaking the dura mater. We demonstrated that 2.0 mWh UV irradiation, but not the same amount of non-UV light irradiation, induced an inverted bell-shaped lesion with neuronal loss and accumulation of glial cells. Moreover, the volume of the UV irradiation-induced lesion depended on the UV light exposure amount. We further succeeded in visualizing the lesioned site in a living animal using magnetic resonance imaging (MRI). Importantly, we also observed using an optical imaging technique that the spread of neural activation evoked by adjacent cortical stimulation disappeared only at the UV-irradiated site. In summary, UV irradiation can induce a focal brain lesion with a stable shape and size in a less invasive manner than traditional lesioning methods. This method is applicable to not only neuroscientific lesion experiments but also studies of the focal brain injury recovery process.

Application of gamma irradiation for inhibition of food allergy

NASA Astrophysics Data System (ADS)

Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Jo, Cheorun; Kim, Hee-Yun

2002-03-01

This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk β-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods.

Food irradiation in the UK and the European Directive

NASA Astrophysics Data System (ADS)

Woolston, John

2000-03-01

Food irradiation in the UK has been authorised since the early 1990s. In principle it is possible to irradiate a wide range of foods for a variety of purposes. In practice food irradiation is virtually non-existent. The structure of food retailing in the UK, a continual stream of food safety scares and a developing public 'crisis of confidence' in the food producer/supply chain have combined to make the future for food irradiation look bleak. The new European Directive on Food Irradiation is unlikely to alter this outlook.

Total body calcium analysis. [neutron irradiation

NASA Technical Reports Server (NTRS)

Lewellen, T. K.; Nelp, W. B.

1974-01-01

A technique to quantitate total body calcium in humans is developed. Total body neutron irradiation is utilized to produce argon 37. The radio argon, which diffuses into the blood stream and is excreted through the lungs, is recovered from the exhaled breath and counted inside a proportional detector. Emphasis is placed on: (1) measurement of the rate of excretion of radio argon following total body neutron irradiation; (2) the development of the radio argon collection, purification, and counting systems; and (3) development of a patient irradiation facility using a 14 MeV neutron generator. Results and applications are discussed in detail.

ARTERIAL HYPERTENSION AND IRRADIATION DAMAGE TO THE NERVOUS SYSTEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Asscher, A.W.; Anson, S.G.

1962-12-29

On the basis of previous studies it appeared that irradiation damage to the nervous system might be more severe and more easily produced in hypertensive than in normotensive subjects. This hypothesis was investigated by studying the frequency of neurological complications and vascular lesions in the spinal cord after x irradiation of the cord in hypertensive and normotensive rats. Two weeks before irradiation of the spinal cord, a clip was applied to the right renal artery of the animals to produce hypertension. Single doses of 1500, 2000, or 3000 r were administered to the spinal cord in the cervical and uppermore » thoracic region of hypertensive rats (systolic blood pressure higher than 145 mm Hg) and normotensive rats. After 1500 r to spinal cord, no abnormalities were noted in the normotensive controls during the period of observation. Some hypertensive animaIs showed transient abnormalities of gait, and during the following week died suddenly. Those remaining died unexpectedly 35-259 days after irradiation without apparent preceding neurological manifestations, although acute vascular lesions were found in the irradiated regions of the spinal cord. The normotensive controls of the 2000-r group showed no abnormalities of gait or of tail sensation, but the hypertensive rats died 67-243 days after irradiation, and ntaxic episodes preceding these unexpected deaths in one animal. Ristologically, the irradiated segments of the cords showed multiple focal acute vascular necrosis. The smaller arteries in irradiated segments of the cords showed hyaline thickening; some of the smaller vessels were widely dilated and filled with blood, and their walls were necrotic. The white matter of the irradiated parts of these cords showed numerous holes (status spongiosus) in the lateral and dorsal columns. The anterior-horn cells in the irradiated zones were swollen, their nuclei pyknotic and cytoplasm devoid of Nissl granules. No abnormalities, besides thickening of the

Extreme ultraviolet spectral irradiance measurements since 1946

NASA Astrophysics Data System (ADS)

Schmidtke, G.

2015-03-01

irradiance camera (STI-Cam) and also be used investigating real-time space weather effects and deriving more detailed correction procedures for the evaluation of Global Navigation Satellite System (GNSS) signals. Progress in physics goes with achieving higher accuracy in measurements. This review historically guides the reader on the ways of exploring the impact of the variable solar radiation in the extreme ultraviolet spectral region on our upper atmosphere in the altitude regime from 80 to 1000 km.

Crystal plasticity modeling of irradiation growth in Zircaloy-2

DOE PAGES

Patra, Anirban; Tome, Carlos; Golubov, Stanislav I.

2017-05-10

A reaction-diffusion based mean field rate theory model is implemented in the viscoplastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. A novel scheme is proposed to model the evolution (both number density and radius) of irradiation-induced dislocation loops that can be informed directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behavior of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, texture, and external stress onmore » the coupled irradiation growth and creep behavior are also studied.« less

Crystal plasticity modeling of irradiation growth in Zircaloy-2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patra, Anirban; Tome, Carlos; Golubov, Stanislav I.

A reaction-diffusion based mean field rate theory model is implemented in the viscoplastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. A novel scheme is proposed to model the evolution (both number density and radius) of irradiation-induced dislocation loops that can be informed directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behavior of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, texture, and external stress onmore » the coupled irradiation growth and creep behavior are also studied.« less

Fuel or irradiation subassembly

DOEpatents

Seim, O.S.; Hutter, E.

1975-12-23

A subassembly for use in a nuclear reactor is described which incorporates a loose bundle of fuel or irradiation pins enclosed within an inner tube which in turn is enclosed within an outer coolant tube and includes a locking comb consisting of a head extending through one side of the inner sleeve and a plurality of teeth which extend through the other side of the inner sleeve while engaging annular undercut portions in the bottom portion of the fuel or irradiation pins to prevent movement of the pins.

Detection of irradiated fruits by gas-chromatographic methods.

PubMed

el-Dien, S; Farag, A

1996-06-01

To detect those fruits which have been subjected to low-dose irradiation (0.5-3 kGy), two methods of chromatography (GC-MS and LC-LC-GC-FID) were used to determine the radiolytic compounds of lipids formed after irradiation, such as alkanes and alkenes. Extraction of volatile hydrocarbon compounds from some parts of irradiated fruits, e.g. the flesh (avocado), seeds (papaya) and kernels (mango and apricot) was carried out. The analysis of hydrocarbons by GC-MS proved the suitability of using C17:1, C16:2, C15:0 and C14:1 as markers for avocados irradiated with a low dose (0.75 kGy). The same indicators appeared following the analysis of papayas and mangoes irradiated with 1.5, and 3.0 kGy. Also, C15:0, C14:1 and C16:3 can be used to identify apricots irradiated with a low dose (0.5 kGy). The detection of alkenes was only improved by a more selective isolation, e.g. of dienes or trienes by LC-LC-GC-FID. Within a few minutes, apricots and avocados irradiated at low doses (0.5 and 0.75 kGy) can be recognized by the indicators C16:2, C17:2 and C16:3, without interfering peaks. In all cases, C16:1, C16:2, C16:3 as well as significant amounts of C17:2 can be used as markers for fruit irradiation.

A methodology for the stochastic generation of hourly synthetic direct normal irradiation time series

NASA Astrophysics Data System (ADS)

Larrañeta, M.; Moreno-Tejera, S.; Lillo-Bravo, I.; Silva-Pérez, M. A.

2018-02-01

Many of the available solar radiation databases only provide global horizontal irradiance (GHI) while there is a growing need of extensive databases of direct normal radiation (DNI) mainly for the development of concentrated solar power and concentrated photovoltaic technologies. In the present work, we propose a methodology for the generation of synthetic DNI hourly data from the hourly average GHI values by dividing the irradiance into a deterministic and stochastic component intending to emulate the dynamics of the solar radiation. The deterministic component is modeled through a simple classical model. The stochastic component is fitted to measured data in order to maintain the consistency of the synthetic data with the state of the sky, generating statistically significant DNI data with a cumulative frequency distribution very similar to the measured data. The adaptation and application of the model to the location of Seville shows significant improvements in terms of frequency distribution over the classical models. The proposed methodology applied to other locations with different climatological characteristics better results than the classical models in terms of frequency distribution reaching a reduction of the 50% in the Finkelstein-Schafer (FS) and Kolmogorov-Smirnov test integral (KSI) statistics.

LOCAL ANESTHESIA IN IRRADIATED ANIMALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lazovskaya, A.V.

1964-03-01

Experiments were conducted on animals subjected to x irradistion. A study was made of the features peculiar to the effect of local anesthetizing agents in various types of anesthesia. As revealed, the effect of decicaine on the cornea of the eye (terminal anesthesia) became intensified during the first hours after the irradiation of the animals (rabbits-- 1000 r) and reduced by the end of the first 24 hr. The initial value of the effect was restored by the third day. The extent of novocaine block of the sensitive conductors (conduction anesthesia) is greater in irradiated animals (frog- 5000 r) thanmore » that in nonirradiated ones. The analgesic effect of anesthetics (novocaine, benzocaine, mesocaine) weakened during infiltration anesthesia administered to the irradiated animals (guinea pigs--350 r). (auth)« less

Renal effects of renal x irradiation and induced autoallergic glomerulonephritis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rappaport, D.S.; Casarett, G.W.

1979-09-01

This study was conducted to determine what influence a single large x-ray exposure of kidney has on the development and course of an experimental autoallergic glomerulonephritis (EAG) in rats. EAG was induced in female Sprague-Dawley rats by immunization with Bordetella pertussis vaccine and homogenate of homologous kidney tissue and Freund's complete adjuvant. Progressive arteriolonephrosclerosis (ANS) was observed in right (irradiated) kidneys following unilateral renal irradiation (1500 rad). Rats were either immunized, sham-immunized, irradiated, sham-irradiated, or both immunized and irradiated. Light and immunofluorescent microscopic observation, urine protein content, and kidney weights were evaluated. In immunized-irradiated animals the effects of irradiation andmore » immunization were largely additive. Immunization did not considerably influence the development and course of ANS and irradiation did not considerably influence the development and course of EAG.« less

Crystal plasticity modeling of irradiation growth in Zircaloy-2

NASA Astrophysics Data System (ADS)

Patra, Anirban; Tomé, Carlos N.; Golubov, Stanislav I.

2017-08-01

A physically based reaction-diffusion model is implemented in the visco-plastic self-consistent (VPSC) crystal plasticity framework to simulate irradiation growth in hcp Zr and its alloys. The reaction-diffusion model accounts for the defects produced by the cascade of displaced atoms, their diffusion to lattice sinks and the contribution to crystallographic strain at the level of single crystals. The VPSC framework accounts for intergranular interactions and irradiation creep, and calculates the strain in the polycrystalline ensemble. A novel scheme is proposed to model the simultaneous evolution of both, number density and radius, of irradiation-induced dislocation loops directly from experimental data of dislocation density evolution during irradiation. This framework is used to predict the irradiation growth behaviour of cold-worked Zircaloy-2 and trends compared to available experimental data. The role of internal stresses in inducing irradiation creep is discussed. Effects of grain size, texture and external stress on the coupled irradiation growth and creep behaviour are also studied and compared with available experimental data.

A Retailer's Experience with Irradiated Foods

DOE Office of Scientific and Technical Information (OSTI.GOV)

James P. Corrigan

2000-11-12

A food irradiation success story comes from Northbrook, Illinois, where Carrot Top, Inc., has been routinely carrying irradiated food for more than 7 yr. This paper presents the experiences of Carrot Top during those years, details the marketing approaches used, and summarizes the resulting sales figures.

Schedule and status of irradiation experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowcliffe, A.F.; Grossbeck, M.L.; Robertson, J.P.

1998-09-01

The current status of reactor irradiation experiments is presented in tables summarizing the experimental objectives, conditions, and schedule. Currently, the program has one irradiation experiment in reactor and five experiments in the design or construction stages. Postirradiation examination and testing is in progress on ten experiments.

Consumer acceptance of irradiated food: theory and reality

NASA Astrophysics Data System (ADS)

Bruhn, Christine M.

1998-06-01

For years most consumers have expressed less concern about food irradiation than other food processing technologies. Attitude studies have demonstrated that when given science-based information, from 60% to 90% of consumers prefer the advantages irradiation processing provides. When information is accompanied by samples, acceptance may increase to 99%. Information on irradiation should include product benefits, safety and wholesomeness, address environmental safety issues, and include endorsements by recognized health authorities. Educational and marketing programs should now be directed toward retailers and processors. Given the opportunity, consumers will buy high quality, safety-enhanced irradiated food.

Food irradiation: Technology transfer in Asia, practical experiences

NASA Astrophysics Data System (ADS)

Kunstadt, Peter; Eng, P.

1993-10-01

Nordion International Inc., in cooperation with the Thai Office of Atomic Energy for Peace (OAEP) and the Canadian International Development Agency (CIDA) recently completed a unique food irradiation technology transfer project in Thailand. This complete food irradiation technology transfer project included the design and construction of an automatic multipurpose irradiation facility as well as the services of construction and installation management and experts in facility operation, maintenance and training. This paper provides an insight into the many events that led to the succesful conclusion of the world's first complete food irradiation technology transfer project.

Cost of irradiating bacon and the associated energy savings. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brynjolfsson, A.

1979-03-01

This paper is about costs and energy savings obtained by irradiating bacon. Sterilized by irradiation (25 kGy), bacon without added nitrite does not contain nitrosamines and does not constitute botulism hazard. If bacon is irradiation sterilized while refrigerated, the cost of irradiation is about $0.08/lb; if irradiation-sterilized while frozen, the costs of irradiation and freezing would be about $0.03/lb. Substerilizing irradiation doses of 7.5 to 15 kGy would give about 80 days extension of bacon stored and distributed refrigerated. The irradiation costs, in this case, would be about $0.07/lb.

IRRADIATION-CAPSULE STUDY OF URANIUM MONOCARBIDE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, R.B.; Stahl, D.; Stang, J.H.

1960-03-01

Small cylindrical specimens of enriched UC were irradiated to evaluate usefulness as a high-temperature fuel for stationary power reactors. Detailed thermal and nuclear analyses were made to arrive at an appropriate capsule design on the basis of target specimen center-line temperature ( approximately 1500 deg F), specimen surface temperature (1100 deg F), specimen composition (U--5 wt.% C), and acapsule o.d. of 1.125 in. Temperature data from thermocouples inside the capsule indicated that five of the six capsules irradiated operated at close to the design conditions. Irradiation periods for individual capsules were varied to give burnups ranging from 1,000 to 20,000more » Mwd/t of U. Preliminary evidence indicates that this range of burnups was achieved. By using temperature and heat-flux data from the actual irradiations to estimate effective in-pile specimen thermal conductivities, it was found that the conductivity did not appear to vary during the exposures. (auth)« less

X-ray irradiation of yeast cells

NASA Astrophysics Data System (ADS)

Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

1997-10-01

Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

Regulation of tomato fruit ascorbate content is more highly dependent on fruit irradiance than leaf irradiance

PubMed Central

Gautier, Hélène; Massot, Capucine; Stevens, Rebecca; Sérino, Sylvie; Génard, Michel

2009-01-01

Background and Aims The mechanisms involving light control of vitamin C content in fruits are not yet fully understood. The present study aimed to evaluate the impact of fruit and leaf shading on ascorbate (AsA) accumulation in tomato fruit and to determine how fruit sugar content (as an AsA precursor) affected AsA content. Methods Cherry tomato plants were grown in a glasshouse. The control treatment (normally irradiated fruits and irradiated leaves) was compared with the whole-plant shading treatment and with leaf or fruit shading treatments in fruits harvested at breaker stage. In a second experiment, the correlation between sugars and AsA was studied during ripening. Key Results Fruit shading was the most effective treatment in reducing fruit AsA content. Under normal conditions, AsA and sugar content were correlated and increased with the ripening stage. Reducing fruit irradiance strongly decreased the reduced AsA content (−74 %), without affecting sugars, so that sugar and reduced AsA were no longer correlated. Leaf shading delayed fruit ripening: it increased the accumulation of oxidized AsA in green fruits (+98 %), whereas it decreased the reduced AsA content in orange fruits (−19 %), suggesting that fruit AsA metabolism also depends on leaf irradiance. Conclusions Under fruit shading only, the absence of a correlation between sugars and reduced AsA content indicated that fruit AsA content was not limited by leaf photosynthesis or sugar substrate, but strongly depended on fruit irradiance. Leaf shading most probably affected fruit AsA content by delaying fruit ripening, and suggested a complex regulation of AsA metabolism which depends on both fruit and leaf irradiance and fruit ripening stage. PMID:19033285

Antimicrobial properties of natural substances in irradiated fresh poultry

NASA Astrophysics Data System (ADS)

Mahrour, A.; Lacroix, M.; Nketsa-Tabiri, J.; Calderon, N.; Gagnon, M.

1998-06-01

This study was undertaken to determine if a combined treatment (marinating in natural plant extracts or vacuum) with irradiation could have a synergetic effect, in order to reduce the dose required for complete elimination of Salmonella on fresh poultry. The effect of these combined treatments on the shelf-life extension was also evaluated. The fresh chicken legs were irradiated at 0, 3 and 5 kGy. The poultry underwent microbial analysis(mesophilic and Salmonella detection). For each treatment, the total microbial count decreased with increase of irradiation dose. The marinating treatment have a synergistic effect with irradiation treatment to reduce the total microbial count and controlling the proliferation during storage at 4°C. Irradiation of fresh chicken pieces with a dose of 3 kGy appears to be able to extend the microbial shelf-life by a factor of 2. When the chicken is marinating and irradiated at 3 kGy or when irradiated at 5 kGy without marinating, the microbial shelf-life is extended by a factor of 7 to 8. No Salmonella was found during all the experiment in the chicken in air and marinated. However, a presence of Salmonella was found in samples irradiated at 5 kGy under vacuum, in unirradiated samples and samples irradiated at 3kGy in air and under vacuum.

Effect of post-irradiation annealing on the irradiated microstructure of neutron-irradiated 304L stainless steel

NASA Astrophysics Data System (ADS)

Jiao, Z.; Hesterberg, J.; Was, G. S.

2018-03-01

Post-irradiation annealing was performed on a 304L SS that was irradiated to 5.9 dpa in the Barsebäck 1 BWR reactor. Evolution of dislocation loops, radiation-induced solute clusters and radiation-induced segregation at the grain boundary was investigated following thermal annealing at 500 °C and 550 °C up to 20 h. Dislocation loops, Ni-Si and Al-Cu clusters, and enrichment of Ni, Si and depletion of Cr at the grain boundary were observed in the as-irradiated condition. Dislocation loop size did not change significantly after annealing at 550 °C for 5 h but the loop number density decreased considerably and loops mostly disappeared after annealing at 550 °C for 20 h. The average size of Ni-Si and Al-Cu clusters increased while the number density decreased with annealing. The increase in cluster size was due to diffusion of solutes rather than cluster coarsening. Significant volume fractions of Ni-Si and Al-Cu clusters still remained after annealing at 550 °C for 20 h. Substantial recovery of Cr and Ni at the grain boundary was observed after annealing at 550 °C for 5 h but neither Cr nor Ni was fully recovered after 20 h. Annihilation of dislocation loops, driven by the thermal vacancy concentration gradient caused by the strain field and stacking fault associated with the loops appeared to be faster than annihilation of solute clusters and recovery of Ni and Si at the grain boundary, both of which are driven by the solute concentration gradients.

RESULTS OF THE CANADIAN POTATO IRRADIATION PROGRAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hetherington, C.H.; MacQueen, K.F.

1963-01-01

Results of test irradiations of potatoes in Canada between October 1961 and March 1962 are reviewed. Completely effective sprout inhibition was obtained in all cases. Radiation treatment was observed to be more effective than other methods. A lower dosage level would probably be satisfactory on a commercial basis. There was no internal sprouting and irradiated potatoes remained firmer than controls. Some dry rot was present in both control and treated potatoes. Irradiated potatoes were found to be more resistant to light greening. The quality of chips, instant mashed potatoes, frozen French fries, and fresh boilers produced from irradiated potatoes wasmore » found to be good. Implications and plans for commercialization of the process are discussed. (H.M.G.)« less

Performance of irradiated CVD diamond micro-strip sensors

NASA Astrophysics Data System (ADS)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L. S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J. L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R. J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.; Plano, R.; Somalwar, S. V.; Thomson, G. B.

2002-01-01

CVD diamond detectors are of interest for charged particle detection and tracking due to their high radiation tolerance. In this article, we present, for the first time, beam test results from recently manufactured CVD diamond strip detectors and their behavior under low doses of electrons from a β-source and the performance before and after intense (>10 15/cm 2) proton- and pion-irradiations. We find that low dose irradiation increase the signal-to-noise ratio (pumping of the signal) and slightly deteriorate the spatial resolution. Intense irradiation with protons 2.2×10 15 p/ cm2 lowers the signal-to-noise ratio slightly. Intense irradiation with pions 2.9×10 15 π/ cm2 lowers the signal-to-noise ratio more. The spatial resolution of the diamond sensors improves after irradiations.

Commercial scale irradiation for insect disinfestation preserves peach quality

NASA Astrophysics Data System (ADS)

McDonald, Heather; McCulloch, Mary; Caporaso, Fred; Winborne, Ian; Oubichon, Michon; Rakovski, Cyril; Prakash, Anuradha

2012-06-01

Irradiation is approved as a generic quarantine treatment by the US Department of Agriculture, Animal and Plant Health Inspection Service. Due to the effectiveness of irradiation in controlling insects on commodities, there is a growing need to understand the effects of low dose irradiation on fruit quality. The goal of this study was to determine the sensitivity of peaches (Prunus persica) to irradiation, and secondly, to determine the effect of commercial scale treatment on shelf-life, overall quality and consumer liking. Six varieties of peaches were irradiated in small batches at 0.29, 0.49, 0.69 and 0.90 kGy to observe the sensitivity of peaches at different dose levels. Changes in quality were evaluated by 8 trained panelists using descriptive analysis. Sensory characteristics (color, smoothness, aroma, touch firmness, mouth firmness, graininess, overall flavor and off-flavor) were evaluated at 2-4 day intervals and untreated samples served as control. To simulate commercial treatment, peaches were irradiated in pallet quantities at a target dose level of 0.4 kGy. The average absorbed dose was 0.66 kGy with an average dose uniformity ratio of 1.57. Commercially treated peaches were evaluated by 40-80 untrained consumers for acceptability routinely throughout the shelf life. Titratable acidity, Brix, texture and weight loss were also monitored for both commercial and small scale irradiated peaches. There was no dose effect on TA, Brix and weight loss due to irradiation. Peaches irradiated at 0.69 and 0.90 kGy were darker in flesh color, more juicy and less firm as determined by the trained panel and analytical pressure tests. Commercial scale irradiation did not adversely affect shelf life but was seen to enhance ripening. This, however, was perceived as a positive change by consumers. Overall, consumers rated the acceptability of irradiated peaches higher than untreated peaches. Statistical analysis was performed using linear mixed models to find determinates

Identification of irradiated mushrooms (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muenzner, R.

1973-01-01

A very simple method is described using a 2,3,5-triphenyltetrazolium chloride solution as an indicator. The experiments have shown that only non- irradiated mushrooms could reduce the indicator solution to the red triphenylfornsazane. In the case of irradiated mushrooms, the solution retains its brown color. (GE)

Electron beam irradiation effects on ethylene-tetrafluoroethylene copolymer films

NASA Astrophysics Data System (ADS)

Nasef, Mohamed Mahmoud; Saidi, Hamdani; Dahlan, Khairul Zaman M.

2003-12-01

The effects of electron beam irradiation on ethylene-tetrafluoroethylene copolymer (ETFE) films were studied. Samples were irradiated in air at room temperature by a universal electron beam accelerator for doses ranging from 100 to 1200 kGy. Irradiated samples were investigated with respect to their chemical structure, thermal characteristics, crystallinity and mechanical properties using FTIR, differential scanning calorimeter (DSC) and universal mechanical tester. The interaction of electron irradiation with ETFE films was found to induce dose-dependent changes in all the investigated properties. A mechanism for electron-induced reactions is proposed to explain the structure-property behaviour of irradiated ETFE films.

Validation of gamma irradiator controls for quality and regulatory compliance

NASA Astrophysics Data System (ADS)

Harding, Rorry B.; Pinteric, Francis J. A.

1995-09-01

Since 1978 the U.S. Food and Drug Administration (FDA) has had both the legal authority and the Current Good Manufacturing Practice (CGMP) regulations in place to require irradiator owners who process medical devices to produce evidence of Irradiation Process Validation. One of the key components of Irradiation Process Validation is the validation of the irradiator controls. However, it is only recently that FDA audits have focused on this component of the process validation. What is Irradiator Control System Validation? What constitutes evidence of control? How do owners obtain evidence? What is the irradiator supplier's role in validation? How does the ISO 9000 Quality Standard relate to the FDA's CGMP requirement for evidence of Control System Validation? This paper presents answers to these questions based on the recent experiences of Nordion's engineering and product management staff who have worked with several US-based irradiator owners. This topic — Validation of Irradiator Controls — is a significant regulatory compliance and operations issue within the irradiator suppliers' and users' community.

Gamma irradiation reduces the immunological toxicity of doxorubicin, anticancer drug

NASA Astrophysics Data System (ADS)

Kim, Jae-Hun; Sung, Nak-Yun; Raghavendran, H. Balaji; Yoon, Yohan; Song, Beom-Seok; Choi, Jong-il; Yoo, Young-Choon; Byun, Myung-Woo; Hwang, Young-Jeong; Lee, Ju-Woon

2009-07-01

Doxorubicin (DOX) is a widely used anticancer agent, but exhibits some immunological toxicity to patients during chemotherapy. The present study was conducted to evaluate the effect of gamma irradiation on the immunological response and the inhibition activity on in vivo tumor mass of DOX. The results showed that DOX irradiated at 10 and 20 kGy reduce the inhibition of mouse peritoneal macrophage proliferation and induce the release of cytokines (TNF-α and IL-6) when compared with non-irradiated DOX. The cytotoxicity against human breast (MCF-7), murine colon adenocarcinoma (Colon 26) and human monocytic (THP-1) tumor cell were not significantly different between non-irradiated and irradiated DOX ( P<0.05). In vivo study on the tumor mass inhibition, gamma-irradiated DOX showed a considerable inhibition of tumor mass and this effect was statistically non-significant as compared with non-irradiated DOX. In conclusion, gamma irradiation could be regarded as a potential method for reducing the immunological toxicity of DOX. Further researches is needed to reveal the formation and activity of radiolysis products by gamma irradiation.

Electron spin resonance identification of irradiated fruits

NASA Astrophysics Data System (ADS)

Raffi, Jacques J.; Agnel, Jean-Pierre L.

The electron spin resonance spectrum of achenes, pips, stalks and stones from irradiated fruits (strawberry, raspberry, red currant, bilberry, apple, pear, fig, french prune, kiwi, water-melon and cherry) always displays, just after γ-treatment, a weak triplet ( aH≈30 G) due to a cellulose radical; its left line (lower field) can be used as an identification test of irradiation, at least for strawberries, rapsberries, red currants or bilberries irradiated in order to improve their storage time.

Proton irradiation effects on beryllium - A macroscopic assessment

NASA Astrophysics Data System (ADS)

Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; Camino, Fernando

2016-10-01

Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting its lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This paper focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.

High Fidelity Ion Beam Simulation of High Dose Neutron Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Was, Gary; Wirth, Brian; Motta, Athur

The objective of this proposal is to demonstrate the capability to predict the evolution of microstructure and properties of structural materials in-reactor and at high doses, using ion irradiation as a surrogate for reactor irradiations. “Properties” includes both physical properties (irradiated microstructure) and the mechanical properties of the material. Demonstration of the capability to predict properties has two components. One is ion irradiation of a set of alloys to yield an irradiated microstructure and corresponding mechanical behavior that are substantially the same as results from neutron exposure in the appropriate reactor environment. Second is the capability to predict the irradiatedmore » microstructure and corresponding mechanical behavior on the basis of improved models, validated against both ion and reactor irradiations and verified against ion irradiations. Taken together, achievement of these objectives will yield an enhanced capability for simulating the behavior of materials in reactor irradiations.« less

Whole-body γ-irradiation decelerates rat hepatocyte polyploidization.

PubMed

Ikhtiar, Adnan M

2015-07-01

To characterize hepatocyte polyploidization induced by intermediate dose of γ-ray. Male Wistar strain rats were whole-body irradiated (WBI) with 2 Gy of γ-ray at the age of 1 month, and 5-6 rats were sacrificed monthly at 0-25 months after irradiation. The nuclear DNA content of individual hepatocytes was measured by flow cytometry, then hepatocytes were classified into various ploidy classes. Survival percentage, after exposure up to the end of the study, did not indicate any differences between the irradiated groups and controls. The degree of polyploidization in hepatocytes of irradiated rats, was significantly lower than that for the control after 1 month of exposure, and it continued to be lower after up to 8 months. Thereafter, the degree of polyploidization in the irradiated group slowly returned to the control level when the irradiated rats reached the age of 10 months. Intermediate dose of ionizing radiation, in contrast to high doses, decelerate hepatocyte polyploidization, which may coincides with the hypothesis of the beneficial effects of low doses of ionizing radiation.

Correlations Between Variations in Solar EUV and Soft X-Ray Irradiance and Photoelectron Energy Spectra Observed on Mars and Earth

NASA Technical Reports Server (NTRS)

Peterson, W. K.; Brain, D. A.; Mitchell, D. L.; Bailey, S. M.; Chamberlin, P. C.

2013-01-01

Solar extreme ultraviolet (EUV; 10-120 nm) and soft X-ray (XUV; 0-10 nm) radiation are major heat sources for the Mars thermosphere as well as the primary source of ionization that creates the ionosphere. In investigations of Mars thermospheric chemistry and dynamics, solar irradiance models are used to account for variations in this radiation. Because of limited proxies, irradiance models do a poor job of tracking the significant variations in irradiance intensity in the EUV and XUV ranges over solar rotation time scales when the Mars-Sun-Earth angle is large. Recent results from Earth observations show that variations in photoelectron energy spectra are useful monitors of EUV and XUV irradiance variability. Here we investigate photoelectron energy spectra observed by the Mars Global Surveyor (MGS) Electron Reflectometer (ER) and the FAST satellite during the interval in 2005 when Earth, Mars, and the Sun were aligned. The Earth photoelectron data in selected bands correlate well with calculations based on 1 nm resolution observations above 27 nm supplemented by broadband observations and a solar model in the 0-27 nm range. At Mars, we find that instrumental and orbital limitations to the identifications of photoelectron energy spectra in MGS/ER data preclude their use as a monitor of solar EUV and XUV variability. However, observations with higher temporal and energy resolution obtained at lower altitudes on Mars might allow the separation of the solar wind and ionospheric components of electron energy spectra so that they could be used as reliable monitors of variations in solar EUV and XUV irradiance than the time shifted, Earth-based, F(10.7) index currently used.

Correlations between variations in solar EUV and soft X-ray irradiance and photoelectron energy spectra observed on Mars and Earth

NASA Astrophysics Data System (ADS)

Peterson, W. K.; Brain, D. A.; Mitchell, D. L.; Bailey, S. M.; Chamberlin, P. C.

2013-11-01

extreme ultraviolet (EUV; 10-120 nm) and soft X-ray (XUV; 0-10 nm) radiation are major heat sources for the Mars thermosphere as well as the primary source of ionization that creates the ionosphere. In investigations of Mars thermospheric chemistry and dynamics, solar irradiance models are used to account for variations in this radiation. Because of limited proxies, irradiance models do a poor job of tracking the significant variations in irradiance intensity in the EUV and XUV ranges over solar rotation time scales when the Mars-Sun-Earth angle is large. Recent results from Earth observations show that variations in photoelectron energy spectra are useful monitors of EUV and XUV irradiance variability. Here we investigate photoelectron energy spectra observed by the Mars Global Surveyor (MGS) Electron Reflectometer (ER) and the FAST satellite during the interval in 2005 when Earth, Mars, and the Sun were aligned. The Earth photoelectron data in selected bands correlate well with calculations based on 1 nm resolution observations above 27 nm supplemented by broadband observations and a solar model in the 0-27 nm range. At Mars, we find that instrumental and orbital limitations to the identifications of photoelectron energy spectra in MGS/ER data preclude their use as a monitor of solar EUV and XUV variability. However, observations with higher temporal and energy resolution obtained at lower altitudes on Mars might allow the separation of the solar wind and ionospheric components of electron energy spectra so that they could be used as reliable monitors of variations in solar EUV and XUV irradiance than the time shifted, Earth-based, F10.7 index currently used.

Aviation Security Cooperation: Advancing Global Vigilance, Global Reach, and Global Power in a Dynamic World

DTIC Science & Technology

2014-10-01

Views September–October 2014 Air & Space Power Journal | 92 Aviation Security Cooperation Advancing Global Vigilance, Global Reach, and Global Power...2014 to 00-00-2014 4. TITLE AND SUBTITLE Aviation Security Cooperation: Advancing Global Vigilance, Global Reach, and Global Power in a Dynamic

LIGHT SCATTERING PROPERTIES OF GLIADIN AFTER X-RAY IRRADIATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, J.

1962-01-01

The gliadin portion of wheat gluten prepared in 60% ethanol solution was investigated for its light scattering properties after x irradiation. Results show that the effect of irradiation depends on the quality of the sample, such as dry or wet. The average molecular weight of liadin decreased in accordance with the time of irradiation. The longer the irradiated time, the more SH groups were setfree. (P.C.H.)

Trehalose Dimycolate Enhances Survival of Fission Neutron-Irradiated Mice and Klebsiella pneumoniae-Challenged Irradiated Mice

DTIC Science & Technology

1990-01-01

SR90-5 Trehalose Dimycolate Enhances Survival of Fission Neutron-Irradiated Mice and Kiebsiella pneumoniae-Challenged Irradiated Mice 1’ 2 D. (. M...doses kines and immunomodulators of nonspecific resistance to of fission neutron radiation is increased when trehalose dimycol- infection might have... trehalose day before exposure to radiation. TDM in an emulsion of squa- dimycolate (TDM) have been shown to be effective in in- lene. Tween 80, and saline

Low irradiance losses of photovoltaic modules

DOE PAGES

Mavromatakis, F.; Vignola, F.; Marion, Bill

2017-09-01

Here, the efficiency of a photovoltaic cell/module changes, as the intensity of incident irradiance decreases, in a non linear way and these changes are referred to as low irradiance losses. In this study data from field experiments, developed and organized by the National Renewable Energy Laboratory, are used to evaluate the low irradiance losses for a variety of module technologies. The results demonstrate that the ratio of the normalized power divided by the normalized short circuit current provide a good measure of the module's low light efficiency losses after both the maximum power and the short circuit current are adjustedmore » for temperature effects. The normalized efficiencies determined through the field data, spanning for several months, are in good agreement with those determined under controlled conditions in a solar simulator. An analytical relation for the normalized efficiency is proposed based on existing formulation for the fill factor. Despite the approximate nature of the fill factor relation, this approach produces reliable results. It will be shown that a normalized efficiency curve can be used to extract information on the series and shunt resistances of the PV module and that the shunt resistance as a function of solar irradiance can be studied. Alternately, this formulation can be used to study the low irradiance losses of a module when the internal resistances are known.« less

Low irradiance losses of photovoltaic modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mavromatakis, F.; Vignola, F.; Marion, Bill

Here, the efficiency of a photovoltaic cell/module changes, as the intensity of incident irradiance decreases, in a non linear way and these changes are referred to as low irradiance losses. In this study data from field experiments, developed and organized by the National Renewable Energy Laboratory, are used to evaluate the low irradiance losses for a variety of module technologies. The results demonstrate that the ratio of the normalized power divided by the normalized short circuit current provide a good measure of the module's low light efficiency losses after both the maximum power and the short circuit current are adjustedmore » for temperature effects. The normalized efficiencies determined through the field data, spanning for several months, are in good agreement with those determined under controlled conditions in a solar simulator. An analytical relation for the normalized efficiency is proposed based on existing formulation for the fill factor. Despite the approximate nature of the fill factor relation, this approach produces reliable results. It will be shown that a normalized efficiency curve can be used to extract information on the series and shunt resistances of the PV module and that the shunt resistance as a function of solar irradiance can be studied. Alternately, this formulation can be used to study the low irradiance losses of a module when the internal resistances are known.« less

A hybrid system for solar irradiance specification

NASA Astrophysics Data System (ADS)

Tobiska, W.; Bouwer, S.

2006-12-01

Space environment research and space weather operations require solar irradiances in a variety of time scales and spectral formats. We describe the development of solar irradiance characterization using four models and systems that are also used for space weather operations. The four models/systems include SOLAR2000 (S2K), SOLARFLARE (SFLR), APEX, and IDAR, which are used by Space Environment Technologies (SET) to provide solar irradiances from the soft X-rays through the visible spectrum. SFLR uses the GOES 0.1 0.8 nm X-rays in combination with a Mewe model subroutine to provide 0.1 30.0 nm irradiances at 0.1 nm spectral resolution, at 1 minute time resolution, and in a 6-hour XUV EUV spectral solar flare evolution forecast with a 7 minute latency and a 2 minute cadence. These irradiances have been calibrated with the SORCE XPS observations and we report on the inclusion of these irradiances into the S2K model. The APEX system is a real-time data retrieval system developed in conjunction with the University of Southern California Space Sciences Center (SSC) to provide SOHO SEM data processing and distribution. SSC provides the updated SEM data to the research community and SET provides the operational data to the space operations community. We describe how the SOHO SEM data, and especially the new S10.7 index, is being integrated directly into the S2K model for space weather operations. The IDAR system has been developed by SET to extract coronal hole boundaries, streamers, coronal loops, active regions, plage, network, and background (internetwork) features from solar images for comparison with solar magnetic features. S2K, SFLR, APEX, and IDAR outputs are integrated through the S2K solar irradiance platform that has become a hybrid system, i.e., a system that is able to produce irradiances using different processes, including empirical and physics-based models combined with real-time data integration.

TECHNOLOGICAL EFFECTS OF GAMMA IRRADIATION OF WHEAT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Milner, M.

Extensive literature appearing in the past six years suggests that few if any useful modifications of wheat and flour are produced by gamma irradiation. Deinfestation by treatments of 25,000 to 50,000 rep was proposed, but more information is needed about possible deleterious effects. Fungi, the cause of deterioration of damp grain, can be eliminated by irradiation levels around 250,000 rep, but damage to germination, starch, and protein, as well as darkening due to non-enzymatic browning, question the practicality of such treatment for improving storage properties. A decrease in power consumption in milling occurs, probably related to radiation-splitting of starch, whichmore » also involves decrease in dextrin chain length and gelatinization viscosity, as well as increases in maltose value. An increase in the soluble pentosans and loss of their gelling characteristic when treated with oxidizing agents is also observed, paralleling the appearance of major deterioration in breadmaking quality and loss of bromate response. Reduction of grain viability with irradiation is not paralleled by a corresponding drop in formazan production from TTC, due apparently to the formation of browning products, reducing in character (reductones), at high radiation levels. Evidence concerning the effects of irradiation on dough and breadmaking properties is conflicting but the improvement claimed in weak wheats can be explained on the basis of a stimulation in gas production during dough fermentation due to increase in starch degradation products; probably it does not involve beneficial modification of the gluten. Thus, when irradiated flours are baked with optimum quantities of sugar, amylase supplements and oxidizing agents, no improving effect due to irradiation is observed and the damage to bread properties is progressive; it is reversible in terms of loaf volume but not crumb grain by treatment with potassium bromate, but only at moderate irradiation levels. Reduction of dough

Effects of gamma irradiation on deteriorated paper

NASA Astrophysics Data System (ADS)

Bicchieri, Marina; Monti, Michela; Piantanida, Giovanna; Sodo, Armida

2016-08-01

Even though gamma radiation application, also at the minimum dosage required for disinfection, causes depolymerization and degradation of the paper substrate, recently published papers seemed, instead, to suggest that γ-rays application could be envisaged in some conditions for Cultural Heritage original documents and books. In some of the published papers, the possible application of γ-rays was evaluated mainly by using mechanical tests that scarcely reflect the chemical modifications induced in the cellulosic support. In the present article the effect of low dosage γ-irradiation on cellulosic substrates was studied and monitored applying different techniques: colorimetry, spectroscopic measurements, carbonyl content and average viscometric degree of polymerization. Two different papers were investigated, a non-sized, non-filled cotton paper, and a commercial permanent paper. To simulate a real deteriorated document, which could need γ-rays irradiation, some samples were submitted to a hydrolysis treatment. We developed a treatment based on the exposition of paper to hydrochloric acid vapors, avoiding any contact of the samples with water. This method induces a degradation similar to that observed on original documents. The samples were then irradiated with 3 kGy γ-rays at a 5258 Gy/h rate. The aforementioned analyses were performed on the samples just irradiated and after artificial ageing. All tests showed negative effects of gamma irradiation on paper. Non-irradiated paper preserves better its appearance and chemical properties both in the short term and after ageing, while the irradiated samples show appreciable color change and higher oxidation extent. Since the Istituto centrale restauro e conservazione patrimonio archivistico e librario is responsible for the choice of all restoration treatments that could be applied on library and archival materials under the protection of the Italian State (http://www.icpal.beniculturali.it/allegati/DM-7

Solar total and spectral irradiance reconstruction over last 9000 years

NASA Astrophysics Data System (ADS)

Wu, Chi-Ju; Usoskin, Ilya; Krivova, Natalie; Solanki, Sami K.

2016-07-01

Although the mechanisms of solar influence on Earth climate system are not yet fully understood, solar total and spectral irradiance are considered to be among the main determinants. Solar total irradiance is the total flux of solar radiative energy entering Earth's climate system, whereas the spectral irradiance describes this energy is distributed over the spectrum. Solar irradiance in the UV band is of special importance since it governs chemical processes in the middle and upper atmosphere. On timescales of the 11-year solar cycle and shorter, solar irradiance is measured by space-based instruments while models are needed to reconstruct solar irradiance on longer timescale. The SATIRE-M model (Spectral And Total Irradiance Reconstruction over millennia) is employed in this study to reconstruct solar irradiance from decadal radionuclide isotope data such as 14C and 10Be stored in tree rings and ice cores, respectively. A reconstruction over the last 9000 years will be presented.

Solar Total and Spectral Irradiance Reconstruction over Last 9000 Years

NASA Astrophysics Data System (ADS)

Wu, C. J.; Krivova, N.; Solanki, S. K.; Usoskin, I. G.

2016-12-01

Although the mechanisms of solar influence on Earth climate system are not yet fully understood, solar total and spectral irradiance are considered to be among the main determinants. Solar total irradiance is the total flux of solar radiative energy entering Earth's climate system, whereas the spectral irradiance describes this energy is distributed over the spectrum. Solar irradiance in the UV band is of special importance since it governs chemical processes in the middle and upper atmosphere. On timescales of the 11-year solar cycle and shorter, solar irradiance is measured by space-based instruments while models are needed to reconstruct solar irradiance on longer timescale. The SATIRE-M model (Spectral And Total Irradiance Reconstruction over millennia) is employed in this study to reconstruct solar irradiance from decadal radionuclide isotope data such as 14C and 10Be stored in tree rings and ice cores, respectively. A reconstruction over the last 9000 years will be presented.

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Richard W., E-mail: rich.wilson.smith@gmail.com; Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario; Seymour, Colin B.

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyedmore » eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent

EXPERIMENTS ON THE PRESERVATION OF FRESH FRUIT BY IRRADIATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

de Zeeuw, D.

1961-01-01

Soft fruits, such as strawberries, raspberries and plums, were irradiated by means of an electron accelerator. The fruits were placed in small plastic boxes and irradiated on both sides with 1 Mev-electrons. The irradiation dosages varied from 0 to 700 kilorads. The storage temperature was usually 15 deg C. In general the consistency of soft fruits, irradiated with dosages of 300 to 700 kilorads, was superior to that of the non-irradiated fruits. It seems that a medium dose treatment affects both the shelf-life time and the ripening of fruit. In order to investigate the effect of ionizing radiation on themore » ripening process of fruit, experiments were carried out with tomatoes in different stages of maturity. In these investigations tomatoes were used because they do not get mouldy during a long storage period. Consequently, there is no interference of the metabolism of the micro-organisms with that of the tomato. In measuring the CO/sub 2/ production, it appeared that with mature green tomatoes this was considerably increased immediately after irradiation. However, there was no difference between the CO/sub 2/ production of irradiated and non-irradiated tomatoes of the turning mature stage. (auth)« less

Potential chemical markers for the identification of irradiated sausages.

PubMed

Kwon, Joong Ho; Akram, Kashif; Nam, Ki Chang; Min, Byungrok; Lee, Eun Joo; Ahn, Dong U

2012-09-01

Hydrocarbons, gas compounds, and off-odor volatiles were determined for irradiated (0 or 5 kGy) commercial sausages with different fat contents (16% and 29%) during a 60-d storage period at 4 °C. Total of 4 hydrocarbons (C14:1, C15:0, C16:2, and C17:1) were detected only in irradiated sausages: the amount of C16:2 was the highest, followed by C17:1, C14:1, and C15:0. The concentrations of hydrocarbons decreased significantly (P < 0.05) with storage, but were still detectable at the end of 60-d storage. Irradiated sausages produced significantly higher amounts of CO than the nonirradiated ones. CH(4) was detected only in irradiated sausages. Dimethyl disulfide was detected only in irradiated sausages and its concentration decreased significantly (P < 0.05) with storage. Fat content of sausages showed a significant effect on the production and retention of hydrocarbons, gas compounds, and sulfur volatiles in irradiated sausages during storage. Some hydrocarbons (C16:2, C17:1, C14:1, and C15:0), CH(4) , and dimethyl disulfide were only found in irradiated sausages indicating that these compounds can be used as potential markers for irradiated sausages. © 2012 Institute of Food Technologists®

Precipitation in Ni-Si during electron and ion irradiation

NASA Astrophysics Data System (ADS)

Lucas, G. E.; Zama, T.; Ishino, S.

1986-11-01

This study was undertaken to further investigate how the nature of the irradiation condition affects precipitation in a dilute Ni-Si system. Transmission electron microscopy (TEM) discs of a solution annealed Ni alloy containing 5 at% Si were irradiated with 400 keV Ar + ions, 200 keV He + ions and 1 MeV electrons at average displacement rates in the range 2 × 10 -5dpa/s to 2 × 10 -3dpa/s at temperatures in the range 25°C to 450°C. Samples irradiated with electrons were observed in situ in an HVEM, while ion irradiated specimens were examined in a TEM after irradiation. Precipitation of Ni 3Si was detected by the appearance of superlattice spots in the electron diffraction patterns. It was found that as the mass of the irradiating species increased, the lower bound temperature at which Ni 3Si precipitation was first observed increased. For electron irradiation, the lower bound temperature at 2 × 10 -3dpa/s was ˜125°C, whereas for 400 keV Ar + irradiation at a similar average displacement rate the lower boundary was approximately 325°C. This suggests that cascade disordering competes with radiation induced solute segregation.

Irradiation testing of high density uranium alloy dispersion fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, S.L.; Trybus, C.L.; Meyer, M.K.

1997-10-01

Two irradiation test vehicles have been designed, fabricated, and inserted into the Advanced Test Reactor in Idaho. Irradiation of these experiments began in August 1997. These irradiation tests were designed to obtain irradiation performance information on a variety of potential new, high-density dispersion fuels. Each of the two irradiation vehicles contains 32 microplates. Each microplate is aluminum clad, having an aluminum matrix phase and containing one of the following compositions as the fuel phase: U-10Mo, U-8Mo, U-6Mo, U-4Mo, U-9Nb-3Zr, U-6Nb-4Zr, U-5Nb-3Zr, U-6Mo-1Pt, U-6Mo-0.6Ru, U-10Mo-0.05Sn, U{sub 2}Mo, or U{sub 3}Si{sub 2}. These experiments will be discharged at peak fuel burnups ofmore » 40% and 80%. Of particular interest is the fission gas retention/swelling characteristics of these new fuel alloys. This paper presents the design of the irradiation vehicles and the irradiation conditions.« less

Establishment and development of irradiation technology industry in Shenzhen

NASA Astrophysics Data System (ADS)

Shou-yi, Lu

1993-07-01

This paper discusses the establishment and development of radiation processing—the new technology industry in Shenzhen special economic zone, China, from importing a complete set of irradiation equipment to establishing an industrial system of irradiation commercialization. Through the organization of irradiation production, the safety operation of the equipment, the development of irradiation products, the pioneering of technical markets, the increase of economic benefit and the reveal of social benefit, the irradiation technology industry in Shenzhen has formed a productive capacity of 1 million curies of Cobalt-60 just in a few years. This shows a bright future of the new technical industry. This paper also points out that the radiation sterilization is a ripe and practical technology in the present irradiation technology industry. The academic circles and industrial circles in the world now should closely cooperate to make the superior sterilization technology convinced by the public. The appropriate administrative measures should be taken to make it extended and popularized. This not only increases the level of social medical health, but also urges the irradiation technology to have an outstanding development in commercialization.

Spectral irradiance standard for the ultraviolet - The deuterium lamp

NASA Technical Reports Server (NTRS)

Saunders, R. D.; Ott, W. R.; Bridges, J. M.

1978-01-01

A set of deuterium lamps is calibrated as spectral irradiance standards in the 200-350-nm spectral region utilizing both a high accuracy tungsten spectral irradiance standard and a newly developed argon mini-arc spectral radiance standard. The method which enables a transfer from a spectral radiance to a spectral irradiance standard is described. The following characteristics of the deuterium lamp irradiance standard are determined: sensitivity to alignment; dependence on input power and solid angle; reproducibility; and stability. The absolute spectral radiance is also measured in the 167-330-nm region. Based upon these measurements, values of the spectral irradiance below 200 nm are obtained through extrapolation.

Recommendations to mitigate against human health risks incurred due to energetic particle irradiation beyond low earth orbit/BLEO

NASA Astrophysics Data System (ADS)

McKenna-Lawlor, Susan; Bhardwaj, Anil; Ferrari, Franco; Kuznetsov, Nikolay; Lal, Ajay K.; Li, Yinghui; Nagamatsu, Aiko; Nymmik, Rikho; Panasyuk, Michael; Petrov, Vladislav; Reitz, Günther; Pinsky, Lawrence; Shukor, Muszaphar (Sheikh); Singhvi, Ashok K.; Straube, Ulrich; Tomi, Leena; Lawrence, Townsend

2015-04-01

An account is provided of the main sources of energetic particle radiation in interplanetary space (Galactic Cosmic Radiation and Solar Energetic Particles) and career dose limits presently utilized by NASA to mitigate against the cancer and non-cancer effects potentially incurred by astronauts due to irradiation by these components are presented. Certain gaps in knowledge that presently militate against mounting viable human exploration in deep space due to the inherent health risks are identified and recommendations made as to how these gaps might be closed within a framework of global international cooperation.

Physiological activity of irradiated green tea polyphenol on the human skin.

PubMed

An, Bong-Jeun; Kwak, Jae-Hoon; Son, Jun-Ho; Park, Jung-Mi; Lee, Jin-Young; Park, Tae Soon; Kim, So-Yeun; Kim, Yeoung-Sun; Jo, Cheorun; Byun, Myung-Woo

2005-01-01

Physiological activity of irradiated green tea polyphenol on the human skin was investigated for further industrial application. The green tea polyphenol was separated and irradiated at 40 kGy by y-ray. For an anti-wrinkle effect, the collagenase inhibition effect was higher in the irradiated sample (65.3%) than that of the non-irradiated control (56.8%) at 200 ppm of the concentration (p < 0.05). Collagen biosynthesis rates using a human fibroblast were 19.4% and 16.3% in the irradiated and the non-irradiated polyphenols, respectively. The tyrosinase inhibition effect, which is related to the skin-whitening effect, showed a 45.2% and 42.9% in the irradiated and the non-irradiated polyphenols, respectively, at a 100 ppm level. A higher than 90% growth inhibition on skin cancer cells (SK-MEL-2 and G361) was demonstrated in both the irradiated and the non-irradiated polyphenols. Thus, the irradiation of green tea polyphenol did not change and even increased its anti-wrinkle, skin-whitening and anticancer effects on the human skin. The results indicated that irradiated green tea polyphenol can be used as a natural ingredient with excellent physiological functions for the human skin through cosmetic or food composition.

Irradiation dose detection of irradiated milk powder using visible and near-infrared spectroscopy and chemometrics.

PubMed

Kong, W W; Zhang, C; Liu, F; Gong, A P; He, Y

2013-08-01

The objective of this study was to examine the possibility of applying visible and near-infrared spectroscopy to the quantitative detection of irradiation dose of irradiated milk powder. A total of 150 samples were used: 100 for the calibration set and 50 for the validation set. The samples were irradiated at 5 different dose levels in the dose range 0 to 6.0 kGy. Six different pretreatment methods were compared. The prediction results of full spectra given by linear and nonlinear calibration methods suggested that Savitzky-Golay smoothing and first derivative were suitable pretreatment methods in this study. Regression coefficient analysis was applied to select effective wavelengths (EW). Less than 10 EW were selected and they were useful for portable detection instrument or sensor development. Partial least squares, extreme learning machine, and least squares support vector machine were used. The best prediction performance was achieved by the EW-extreme learning machine model with first-derivative spectra, and correlation coefficients=0.97 and root mean square error of prediction=0.844. This study provided a new approach for the fast detection of irradiation dose of milk powder. The results could be helpful for quality detection and safety monitoring of milk powder. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

[Changes in cellular radiosensitivity after low dose irradiation].

PubMed

Pelevina, I I; Aleshchenko, A V; Antoshchina, M M; Kudriashova, O V; Riabchenko, N I; Akleev, A V

2012-01-01

When the adaptive response (AR) was studied on human blood lymphocytes, a new dependence was discovered. This dependence defines the direction of the radiosensitivity change after a low dose of irradiation. Using micronucleus (MN) test with cytochalasin B the dependence between the cell reaction after low level irradiation and radiosensititvity (the effect after irradiation at the dose of 1 Gy) was observed. The negative correlation between the frequency of AR manifestation, sensibilization, intermediate links and radiosensitivity was discovered. This regularity is observed in the population of Moscow, Obninsk, Chelyabinsk region (irradiated and control) inhabitants, Chernobyl accident liquidators, Moscow children, in individuals with Hodgkin's lymphoma before and during treatment. The negative correlation is also noted by AR determination with two irradiation schemes: in one or two different cell cycle phases (G1-G1 or G1-G2). Similar links are observed using the chromosome methaphase analysis (the frequency of cells with chromosome aberrations). So, the results of the experiments conducted allow us to suppose that the connection between the cell radiosensitivity and a different type of reaction after low dose irradiation--from AR to the increase in radiosensitivity (sensibilization) is a general regularity. AR is induced by low level irradiation and high cell radiosensitivity, while sensibilization is induced by low radiosensitivity. Since AR and sensibilization can be induced not only by irradiation, but many different chemicals and physical agents, the described correlation can be observed in the case of different exposures. Cellular AR and sensibilization are integral indexes depending on many genetic and epigenetic factors, as well as on the initiation of a large number of events. However, the discovered mechanisms of interrelations are still difficult to explain.

Characterization of irradiated blends of alpha-tocopherol and UHMWPE.

PubMed

Oral, Ebru; Greenbaum, Evan S; Malhi, Arnaz S; Harris, William H; Muratoglu, Orhun K

2005-11-01

Adhesive/abrasive wear in ultra-high molecular weight polyethylene (UHMWPE) has been minimized by radiation cross-linking. Irradiation is followed by melting to eliminate residual free radicals and avoid long-term oxidative embrittlement. However, post-irradiation melting reduces the crystallinity of the polymer and hence its strength and fatigue resistance. We proposed an alternative to post-irradiation melting to be the incorporation of the antioxidant alpha-tocopherol into UHMWPE prior to consolidation. alpha-Tocopherol is known to react with oxygen and oxidized lipids, stabilizing them against further oxidative degradation reactions. We blended GUR 1050 UHMWPE resin powder with alpha-tocopherol at 0.1 and 0.3 wt% and consolidated these blends. Then we gamma-irradiated these blends to 100-kGy. We characterized the effect of alpha-tocopherol on the cross-linking efficiency, oxidative stability, wear behavior and mechanical properties of the blends. (I) The cross-link density of virgin, 0.1 and 0.3 wt% alpha-tocopherol blended, 100-kGy irradiated UHMWPEs were 175+/-19, 146+/-4 and 93+/-4 mol/m3, respectively. (II) Maximum oxidation indices for 100-kGy irradiated UHMWPE previously blended with 0, 0.1 and 0.3 wt% alpha-tocopherol that were subjected to accelerated aging at 80 degrees C in air for 5 weeks were 3.32, 0.09, and 0.05, respectively. (III) The pin-on-disc wear rates of 100-kGy irradiated UHMWPE previously blended with 0.1 and 0.3 wt% alpha-tocopherol that were subjected to accelerated aging at 80 degrees C in air for 5 weeks were 2.10+/-0.17 and 5.01+/-0.76 mg/million cycles, respectively. (IV) Both accelerated aged, alpha-tocopherol-blended 100-kGy irradiated UHMWPEs showed higher ultimate tensile strength, higher yield strength, and lower elastic modulus when compared to 100-kGy irradiated, virgin UHMWPE. These results showed that alpha-tocopherol-blended 100-kGy irradiated UHMWPEs were not cross-linked to the same extent as the 100-kGy irradiated

Imaging Fourier transform spectroscopy of the boundary layer plume from laser irradiated polymers and carbon materials

NASA Astrophysics Data System (ADS)

Acosta, Roberto I.

The high-energy laser (HEL) lethality community needs for enhanced laser weapons systems requires a better understanding of a wide variety of emerging threats. In order to reduce the dimensionality of laser-materials interaction it is necessary to develop novel predictive capabilities of these events. The objective is to better understand the fundamentals of laser lethality testing by developing empirical models from hyperspectral imagery, enabling a robust library of experiments for vulnerability assessments. Emissive plumes from laser irradiated fiberglass reinforced polymers (FRP), poly(methyl methacrylate) (PMMA) and porous graphite targets were investigated primarily using a mid-wave infrared (MWIR) imaging Fourier transform spectrometer (FTS). Polymer and graphite targets were irradiated with a continuous wave (cw) fiber lasers. Data was acquired with a spectral resolution of 2 cm-1 and spatial resolution as high as 0.52 mm2 per pixel. Strong emission from H2O, CO, CO2 and hydrocarbons were observed in the MWIR between 1900-4000 cm-1. A single-layer radiative transfer model was developed to estimate spatial maps of temperature and column densities of CO and CO2 from the hyperspectral imagery of the boundary layer plume. The spectral model was used to compute the absorption cross sections of CO and CO2, using spectral line parameters from the high temperature extension of the HITRAN. Also, spatial maps of gas-phase temperature and methyl methacrylate (MMA) concentration were developed from laser irradiated carbon black-pigmented PMMA at irradiances of 4-22 W/cm2. Global kinetics interplay between heterogeneous and homogeneous combustion kinetics are shown from experimental observations at high spatial resolutions. Overall the boundary layer profile at steady-state is consistent with CO being mainly produced at the surface by heterogeneous reactions followed by a rapid homogeneous combustion in the boundary layer towards buoyancy.

Guide to solar reference spectra and irradiance models

NASA Astrophysics Data System (ADS)

Tobiska, W. Kent

The international standard for determining solar irradiances was published by the International Standards Organization (ISO) in May 2007. The document, ISO 21348 Space Environment (natural and artificial) - Process for determining solar irradiances, describes the process for representing solar irradiances. We report on the next progression of standards work, i.e., the development of a guide that identifies solar reference spectra and irradiance models for use in engineering design or scientific research. This document will be produced as an AIAA Guideline and ISO Technical Report. It will describe the content of the reference spectra and models, uncertainties and limitations, technical basis, data bases from which the reference spectra and models are formed, publication references, and sources of computer code for reference spectra and solar irradiance models, including those which provide spectrally-resolved lines as well as solar indices and proxies and which are generally recognized in the solar sciences. The document is intended to assist aircraft and space vehicle designers and developers, heliophysicists, geophysicists, aeronomers, meteorologists, and climatologists in understanding available models, comparing sources of data, and interpreting engineering and scientific results based on different solar reference spectra and irradiance models.

Detection of irradiated spices using photo-stimulated luminescence technique (PSL)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi; Othman, Zainon

2014-09-03

Photo-stimulated luminescence (PSL) technique was applied to detect irradiated black pepper (Piper nigrum), cinnamon (Cinnamomum verum) and turmeric (Curcuma longa) after dark storage for 1 day, 3 and 6 months. Using screening and calibrated PSL, all samples were correctly discriminated between non-irradiated and spices irradiated with doses 1, 5 and 10 kGy. The PSL photon counts (PCs) of irradiated spices increased with increasing dose, with turmeric showing highest sensitivity index to irradiation compared to black pepper and cinnamon. The differences in response are possibly attributed to the varying quantity and quality of silicate minerals present in each spice sample. PSLmore » signals of all irradiated samples reduced after 3 and 6 months storage. The results of this study provide a useful database on the applicability of PSL technique for the detection of Malaysian irradiated spices.« less

Detection of irradiated spices using photo-stimulated luminescence technique (PSL)

NASA Astrophysics Data System (ADS)

Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi; Othman, Zainon; Abdullah, Wan Saffiey Wan

2014-09-01

Photo-stimulated luminescence (PSL) technique was applied to detect irradiated black pepper (Piper nigrum), cinnamon (Cinnamomum verum) and turmeric (Curcuma longa) after dark storage for 1 day, 3 and 6 months. Using screening and calibrated PSL, all samples were correctly discriminated between non-irradiated and spices irradiated with doses 1, 5 and 10 kGy. The PSL photon counts (PCs) of irradiated spices increased with increasing dose, with turmeric showing highest sensitivity index to irradiation compared to black pepper and cinnamon. The differences in response are possibly attributed to the varying quantity and quality of silicate minerals present in each spice sample. PSL signals of all irradiated samples reduced after 3 and 6 months storage. The results of this study provide a useful database on the applicability of PSL technique for the detection of Malaysian irradiated spices.

Understanding the Irradiation Behavior of Zirconium Carbide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Motta, Arthur; Sridharan, Kumar; Morgan, Dane

2013-10-11

Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known aboutmore » basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC-based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation

Constant-dose microwave irradiation of insect pupae

NASA Astrophysics Data System (ADS)

Olsen, Richard G.

Pupae of the yellow mealworm Tenebrio molitor L. were subjected to microwave irradiation for 1.5-24 hours at power density levels adjusted to produce a total dosage of approximately 1123 J/g in each insect for every experiment. Insects without visible blemishes were exposed in a standing wave irradiation system such that half of them were exposed in the plane of maximum electric field (E field) and the other half were exposed in the plane of maximum magnetic field (H field). Both E field and H field insects exhibited nearly the same specific absorption rate (SAR) for pupal orientation parallel to the magnetic field vector at 5.95 GHz. Irradiations were conducted both with and without the use of a ventilating fan to control the temperature rise in the irradiation chamber. Abnormal development as a result of the microwave exposure was seen only in the high-power, short-duration experiment without chamber ventilation. This result suggests a thermal interaction mechanism for explanation of observed microwave-induced abnormalities. A study of the time course of the average temperature rise in the irradiated insects indicates that teratological effects for this configuration have a temperature threshold of approximately 40°C.

Carotid artery disease following external cervical irradiation.

PubMed Central

Elerding, S C; Fernandez, R N; Grotta, J C; Lindberg, R D; Causay, L C; McMurtrey, M J

1981-01-01

A retrospective study of 910 patients surviving at least five years after cervical irradiation for Hodgkin's disease, non-Hodgkin's lymphoma, or primary head an neck neoplasms showed the incidence of stroke following cervical irradiation was 63 of 910 patients (6.3%) during a mean period of observation of nine years. This represents a trend toward an increased risk for this population observed over the same period of time (p = 0.39). A prospective study of 118 similar patients currently living five years after cervical radiotherapy was performed to determine the incidence of carotid artery disease occurring as a consequence of neck irradiation. Abnormal carotid phonangiograms (CPA) were found in 25% of the patients and abnormal oculoplethysmographs (OPG) were found in 17%. These studies represent significant carotid lesions that are not expected in such a population. It is concluded that the carotid stenoses demonstrated are most likely a consequence of prior irradiation. Patients that are five-year survivors of cervical irradiation should have noninvasive vascular laboratory studies performed as part of their routine follow-up examinations in order to detect these carotid lesions while they are occult. PMID:7294930

Ultrasonic Transducer Irradiation Test Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daw, Joshua; Palmer, Joe; Ramuhalli, Pradeep

2015-02-01

Ultrasonic technologies offer the potential for high-accuracy and -resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other ongoing efforts include an ultrasonic technique to detect morphology changesmore » (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. For this reason, the Pennsylvania State University (PSU) was awarded an ATR NSUF project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 10 21 n/cm 2. The goal of this research is to characterize and demonstrate magnetostrictive and piezoelectric transducer operation during irradiation, enabling the development of novel radiation-tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. To date, one piezoelectric transducer and two

Long-term reconstructions of total solar irradiance

NASA Astrophysics Data System (ADS)

Krivova, Natalie; Solanki, Sami K.; Dasi Espuig, Maria

2012-07-01

Solar irradiance is the main external driver of the Earth's climate, although its relative contribution compared to other internal and anthropogenic factors is not yet well determined. Variations of total solar irradiance have being measured for over three decades and are relatively well understood. Reconstructions of the irradiance into the past remain, however, rather uncertain. In particular, the magnitude of the secular change is highly debated. The reason is the lack of direct and well-sampled proxies of solar magnetic activity on time scales longer than a few decades. Reconstructions on time scales of centuries rely on sunspot observations available since 1610. Reconstructions on millennial time scales use concentrations of the cosmogenic isotopes in terrestrial archives. We will review long-term reconstructions of the solar irradiance using the SATIRE set of models, compare them with other recent models and discuss the remaining uncertainties.

Backscattering measuring system for optimization of intravenous laser irradiation dose

NASA Astrophysics Data System (ADS)

Rusina, Tatyana V.; Popov, V. D.; Melnik, Ivan S.; Dets, Sergiy M.

1996-11-01

Intravenous laser blood irradiation as an effective method of biostimulation and physiotherapy becomes a more popular procedure. Optimal irradiation conditions for each patient are needed to be established individually. A fiber optics feedback system combined with conventional intravenous laser irradiation system was developed to control of irradiation process. The system consists of He-Ne laser, fiber optics probe and signal analyzer. Intravenous blood irradiation was performed in 7 healthy volunteers and 19 patients with different diseases. Measurements in vivo were related to in vitro blood irradiation which was performed in the same conditions with force-circulated venous blood. Comparison of temporal variations of backscattered light during all irradiation procedures has shown a strong discrepancy on optical properties of blood in patients with various health disorders since second procedure. The best cure effect was achieved when intensity of backscattered light was constant during at least five minutes. As a result, the optical irradiation does was considered to be equal 20 minutes' exposure of 3 mW He-Ne laser light at the end of fourth procedure.

Computation of diffuse sky irradiance from multidirectional radiance measurements

NASA Technical Reports Server (NTRS)

Ahmad, Suraiya P.; Middleton, Elizabeth M.; Deering, Donald W.

1987-01-01

Accurate determination of the diffuse solar spectral irradiance directly above the land surface is important in characterizing the reflectance properties of these surfaces, especially vegetation canopies. This determination is also needed to infer the net radiation budget of the earth-atmosphere system above these surfaces. An algorithm is developed here for the computation of hemispheric diffuse irradiance using the measurements from an instrument called PARABOLA, which rapidly measures upwelling and downwelling radiances in three selected wavelength bands. The validity of the algorithm is established from simulations. The standard reference data set of diffuse radiances of Dave (1978), obtained by solving the radiative transfer equation numerically for realistic atmospheric models, is used to simulate PARABOLA radiances. Hemispheric diffuse irradiance is estimated from a subset of simulated radiances by using the algorithm described. The algorithm is validated by comparing the estimated diffuse irradiance with the true diffuse irradiance of the standard data set. The validations include sensitivity studies for two wavelength bands (visible, 0.65-0.67 micron; near infrared, 0.81-0.84 micron), different atmospheric conditions, solar elevations, and surface reflectances. In most cases the hemispheric diffuse irradiance computed from simulated PARABOLA radiances and the true irradiance obtained from radiative transfer calculations agree within 1-2 percent. This technique can be applied to other sampling instruments designed to estimate hemispheric diffuse sky irradiance.

Stability of zinc stearate under alpha irradiation in the manufacturing process of SFR nuclear fuels

NASA Astrophysics Data System (ADS)

Gracia, J.; Vermeulen, J.; Baux, D.; Sauvage, T.; Venault, L.; Audubert, F.; Colin, X.

2018-03-01

The manufacture of new fuels for sodium-cooled fast reactors (SFRs) will involve powders derived from recycling existing fuels in order to keep on producing electricity while saving natural resources and reducing the amount of waste produced by spent MOX fuels. Using recycled plutonium in this way will significantly increase the amount of 238Pu, a high energy alpha emitter, in the powders. The process of shaping powders by pressing requires the use of a solid lubricant, zinc stearate, to produce pellets with no defects compliant with the standards. The purpose of this study is to determine the impact of alpha radiolysis on this additive and its lubrication properties. Experiments were conducted on samples in contact with PuO2, as well as under external helium ion beam irradiation, in order to define the kinetics of radiolytic gas generation. The yield results relating to the formation of these gases (G0) show that the alpha radiation of plutonium can be simulated using external helium ion beam irradiation. The isotopic composition of plutonium has little impact on the yield. However, an increased yield was globally observed with increasing the mean linear energy transfer (LET). A radiolytic degradation process is proposed.

RERTR-12 Insertion 2 Irradiation Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

D. M. Perez; G. S. Chang; D. M. Wachs

2012-09-01

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

Wavelength Dependence of Solar Irradiance Enhancement During X-Class Flares and Its Influence on the Upper Atmosphere

NASA Technical Reports Server (NTRS)

Huang, Yanshi; Richmond, Arthur D.; Deng, Yue; Chamberlin, Phillip C.; Qian, Liying; Solomon, Stanley C.; Roble, Raymond G.; Xiao, Zuo

2013-01-01

The wavelength dependence of solar irradiance enhancement during flare events is one of the important factors in determining how the Thermosphere-Ionosphere (T-I) system responds to flares. To investigate the wavelength dependence of flare enhancement, the Flare Irradiance Spectral Model (FISM) was run for 61 X-class flares. The absolute and the percentage increases of solar irradiance at flare peaks, compared to pre-flare conditions, have clear wavelength dependences. The 0-14 nm irradiance increases much more (approx. 680% on average) than that in the 14-25 nm waveband (approx. 65% on average), except at 24 nm (approx. 220%). The average percentage increases for the 25-105 nm and 122-190 nm wavebands are approx. 120% and approx. 35%, respectively. The influence of 6 different wavebands (0-14 nm, 14-25 nm, 25-105 nm, 105- 120 nm, 121.56 nm, and 122-175 nm) on the thermosphere was examined for the October 28th, 2003 flare (X17-class) event by coupling FISM with the National Center for Atmospheric Research (NCAR) Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIE-GCM) under geomagnetically quiet conditions (Kp=1). While the enhancement in the 0-14 nm waveband caused the largest enhancement of the globally integrated solar heating, the impact of solar irradiance enhancement on the thermosphere at 400 km is largest for the 25-105 nm waveband (EUV), which accounts for about 33 K of the total 45 K temperature enhancement, and approx. 7.4% of the total approx. 11.5% neutral density enhancement. The effect of 122-175 nm flare radiation on the thermosphere is rather small. The study also illustrates that the high-altitude thermospheric response to the flare radiation at 0-175 nm is almost a linear combination of the responses to the individual wavebands. The upper thermospheric temperature and density enhancements peaked 3-5 h after the maximum flare radiation.

Wavelength Dependence of Solar Irradiance Enhancement During X-class Flares and Its Influence on the Upper Atmosphere

NASA Technical Reports Server (NTRS)

Huang, Yanshi; Richmond, A. D.

2013-01-01

The wavelength dependence of solar irradiance enhancement during flare events is one of the important factors in determining how the Thermosphere-Ionosphere (TI) system responds to flares. To investigate the wavelength dependence of flare enhancement, the Flare Irradiance Spectral Model (FISM) was run for 61X-class flares. The absolute and the percentage increases of solar irradiance at flare peaks, compared to pre-flare conditions, have clear wavelength dependences. The 0-4 nm irradiance increases much more ((is) approximately 680 on average) than that in the 14-25 nm waveband ((is) approximately 65 on average), except at 24 nm ( (is) approximately 220). The average percentage increases for the 25-105 nm and 122-190 nm wave bands are approximately 120 and approximately 35, respectively. The influence of 6 different wavebands (0-14 nm, 14-25 nm, 25-105 nm, 105-120 nm, 121.56 nm,and122-175 nm) on the thermosphere was examined for the October 28th, 2003 flare (X17-class) event by coupling FISM with the National Center for Atmospheric Research (NCAR) Thermosphere-Ionosphere-Electrodynamics General Circulation Model(TIE-GCM) under geomagnetically quiet conditions (Kp=1). While the enhancement in the0-14nm waveband caused the largest enhancement of the globally integrated solar heating, the impact of solar irradiance enhancement on the thermosphere at 400 km is largest for the 25-105 nm waveband (EUV), which accounts for about 33 K of the total 45 K temperature enhancement, and approximately 7.4% of the total approximately 11.5% neutral density enhancement. The effect of 122-175 nm flare radiation on the thermosphere is rather small. The study also illustrates that the high-altitude thermospheric response to the flare radiation at 0-175 nm is almost a linear combination of the responses to the individual wavebands. The upper thermospheric temperature and density enhancements peaked 3-5 h after the maximum flare radiation.

Mechanisms of phosphenes in irradiated patients

PubMed Central

Mathis, Thibaud; Vignot, Stephane; Leal, Cecila; Caujolle, Jean-Pierre; Maschi, Celia; Mauget-Faÿsse, Martine; Kodjikian, Laurent; Baillif, Stéphanie; Herault, Joel; Thariat, Juliette

2017-01-01

Anomalous visual perceptions have been reported in various diseases of the retina and visual pathways or can be experienced under specific conditions in healthy individuals. Phosphenes are perceptions of light in the absence of ambient light, occurring independently of the physiological and classical photonic stimulation of the retina. They are a frequent symptom in patients irradiated in the region of the central nervous system (CNS), head and neck and the eyes. Phosphenes have historically been attributed to complex physical phenomena such as Cherenkov radiation. While phosphenes are related to Cherenkov radiation under high energy photon/electron irradiation conditions, physical phenomena are unlikely to be responsible for light flashes at energies used for ocular proton therapy. Phosphenes may involve a direct role for ocular photoreceptors and possible interactions between cones and rods. Other mechanisms involving the retinal ganglion cells or ultraweak biophoton emission and rhodopsin bleaching after exposure to free radicals are also likely to be involved. Despite their frequency as shown in our preliminary observations, phosphenes have been underreported probably because their mechanism and impact are poorly understood. Recently, phosphenes have been used to restore the vision and whether they might predict vision loss after therapeutic irradiation is a current field of investigation. We have reviewed and also investigated here the mechanisms related to the occurrence of phosphenes in irradiated patients and especially in patients irradiated by proton therapy for ocular tumors. PMID:28969095