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Sample records for incorporating additional wave

  1. Incorporation of additives into polymers

    DOEpatents

    McCleskey, T. Mark; Yates, Matthew Z.

    2003-07-29

    There has been invented a method for incorporating additives into polymers comprising: (a) forming an aqueous or alcohol-based colloidal system of the polymer; (b) emulsifying the colloidal system with a compressed fluid; and (c) contacting the colloidal polymer with the additive in the presence of the compressed fluid. The colloidal polymer can be contacted with the additive by having the additive in the compressed fluid used for emulsification or by adding the additive to the colloidal system before or after emulsification with the compressed fluid. The invention process can be carried out either as a batch process or as a continuous on-line process.

  2. Additional waves in the graphene layered medium.

    PubMed

    Chern, Ruey-Lin; Han, Dezhuan; Zhang, Z Q; Chan, C T

    2014-12-29

    We investigate the features of additional waves that arise in the graphene layered medium, within the framework of nonlocal effective medium model. The additional wave is manifest on the biquadratic dispersion relation of the medium and represents as a distinctive nonlocal character at long wavelength. In particular, the reflection and transmission coefficients for the nonlocal medium are underdetermined by Maxwell's boundary conditions. An additional boundary condition based on modal expansions is proposed to derive the generalized Fresnel equations, based on which the additional wave in the graphene layered medium is determined. The additional wave tends to be significant near the effective plasma frequency, near which the graphene plasmons are excited inside the medium. PMID:25607138

  3. Accelerating procelain formation by incorporating a complex additive

    SciTech Connect

    Maslennikova, G.N.; Dubovitskii, S.A.; Moroz, I.K.

    1986-05-01

    The authors studied the influence of a complex additive consisting of oxides of calcium, zinc, and magnesium on the formaton of porcelain. In order to achieve a more uniform distribution of the complex additive in the porcelain body it was incorporated in the form of water soluble salts-nitrates, which ensured comparability of results and excluded the effect of the different types of anions. The study of the main parameters of sintering (porosity, shrinkage, and mechanical strength) for the test bodies showed that they sinter at lower temperatures and attain zero porosity, maximum shrinkage, and mechanical strength. The most typical bodies indentified in this way were investigated by methods of complex differential thermal analysis and x-ray diffraction. Thus, the introduction of complex additives consisting of calcium, zinc, and magnesium oxides contributes to the earlier formation of porcelain. With the reduction of firing temperatures by 100/sup 0/C the authors observe an improvement in the basic properties of porcelain.

  4. Self-similar blast waves incorporating deflagrations of variable speed

    NASA Technical Reports Server (NTRS)

    Guirguis, R. H.; Kamel, M. M.; Oppenheim, A. K.

    1983-01-01

    The present investigation is concerned with the development of a systematic approach to the problem of self-similar blast waves incorporating nonsteady flames. The regime covered by the presented solutions is bounded on one side by an adiabatic strong explosion and, on the other, by deflagration propagating at an infinite acceleration. Results for a representative set of accelerations are displayed, taking into account the full range of propagation speeds from zero to velocities corresponding to the Chapman-Jouguet deflagration. It is found that the distribution of stored energy in the undisturbed medium determines the acceleration of the deflagration-shock wave system. The obtained results reveal the existence of a simple relation between the location of the deflagration and its Mach number.

  5. Progressive wave tube facility with additional capabilities

    NASA Astrophysics Data System (ADS)

    Lieberman, Paul; Bocksruker, Ron; Pilgram, Mark; Vallance, Charles

    1993-01-01

    The design and development of a new acoustic progressive wave tube facility was required to test the Titan IV rocket engine. Because of the large 6 feet diameter of the nozzle closure, circular shape, high over-all sound pressure level (OASPL), and high sound pressure levels (SPLs) above 1000 Hz, the acoustic environmental tests required consideration of a custom built facility. This paper describes a new oscillating supersonic shock generator (OSSG) for developing the high OASPL, for developing the high SPLs at above 1000 Hz, and for use with a conventional acoustic modulator. Also, the new OSSG permits impedance matching to the test volume annulus via the special geometry of the annular space between the elliptical containment domes upstream of the test volume annulus. A test annulus gap that is too small causes the test article to vibrate with a severe damping imposed by the pumping of trapped air in the annulus, and too large a gap reduces the OASPL. Consideration is given to tuning the axial and circumferential resonance frequencies of the annulus test space so that there is no coincidence with the principal resonant modes of the test structure. Also consideration is given to establishing the reverberant versus propagating modes of the test annulus.

  6. 27 CFR 31.102 - Addition of partners or incorporation of partnership.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... incorporation of partnership. 31.102 Section 31.102 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS ALCOHOL BEVERAGE DEALERS Partnerships § 31.102 Addition of partners or incorporation of partnership. Where a number of persons who have filed...

  7. Incorporating fault zone head wave and direct wave secondary arrival times into seismic tomography: Application at Parkfield, California

    NASA Astrophysics Data System (ADS)

    Bennington, N. L.; Thurber, C. H.; Zhang, H.; Peng, Z.; Zhao, P.

    2011-12-01

    Large crustal faults such as the San Andreas fault (SAF) often juxtapose rocks of significantly different elastic properties, resulting in well-defined bimaterial interfaces. A sharp material contrast across the fault interface is expected to generate fault zone head waves (FZHW's) that spend a large portion of their propagation paths refracting along the bimaterial interface (Ben-Zion 1989, 1990; Ben-Zion & Aki 1990). Because of this FZHW's provide a high-resolution tool for imaging the velocity contrast across the fault. Recently, Zhao et al. (2010) systematically analyzed large data sets of near-fault waveforms recorded by several permanent and temporary seismic networks along the Parkfield section of the SAF. The local-scale tomography study of Zhang et al. (2009) for a roughly 10 km3 volume centered on SAFOD and the more regional-scale study of Thurber et al. (2006) for a 130 km x 120 km x 20 km volume centered on the 2004 Parkfield earthquake rupture provide what are probably the best 3D images of the seismic velocity structure of the area. The former shows a low velocity zone associated with the SAF extending to significant depth, and both image the well-known velocity contrast across the fault. Seismic tomography generally uses just first P and/or S arrivals because of the relative simplicity of phase picking and ray tracing. Adding secondary arrivals such as FZHW's, however, can enhance the resolution of structure and strengthen constraints on earthquake locations and focal mechanisms. We present a model of 3D velocity structure for the Parkfield region that utilizes a combination of arrival times for FZHW's and the associated direct-wave secondary arrivals as well as existing P-wave arrival time data. The resulting image provides a higher-resolution model of the SAF at depth than previously published models. In addition, we plan to measure polarizations of the direct P and S waves and FZHW's and incorporate the data into our updated velocity tomography

  8. Surface-acoustic-wave device incorporating conducting Langmuir-Blodgett films

    NASA Astrophysics Data System (ADS)

    Holcroft, B.; Roberts, G. G.; Barraud, A.; Richard, J.

    1987-04-01

    Surface-acoustic-wave devices incorporating conducting Langmuir-Blodgett films are reported for the first time. Excellent characteristics have been obtained using a mixed valence charge transfer salt of a substituted pyridinium tetracyanoquinodimethane. The control afforded by the deposition technique has enabled the fractional change in surface wave velocity due to the electrical effects to be distinguished from those due to mass loading. The resistivity of the organic surface layer is measured to be 2 ohm-cm.

  9. The Development of Love Wave-Based Humidity Sensors Incorporating Multiple Layers

    PubMed Central

    Wang, Lijun; Liu, Jiansheng; He, Shitang

    2015-01-01

    A Love wave humidity sensor is developed by using a multilayer structure consisting of PVA/SiO2 layers on an ST-90°X quartz substrate. The theoretical result shows that the sensor with such a two-layer structure can achieve a higher sensitivity and a smaller loss than the structures with a single polymer layer. Comparative experiments are performed for the sensor incorporating PVA/SiO2 layers and the sensor incorporating a PVA layer. The experimental results agree well with the theoretical predication. PMID:25875187

  10. P wave velocity structure below India and Tibet incorporating anisotropic delay time effects

    NASA Astrophysics Data System (ADS)

    Mohanty, Debasis D.; Singh, Arun; O'Driscoll, Leland J.; Ravi Kumar, M.; Srinagesh, D.; Humphreys, Eugene D.

    2016-03-01

    We incorporate the effects of anisotropy to refine the continental-scale 3-D isotropic velocity model previously produced for India and Tibet by inverting 52,050 teleseismic P wave residuals. We have exploited a total of 1648 individual SKS splitting parameters to calculate the P wave travel time corrections due to azimuthal anisotropy. Our results suggest that anisotropy affects the P wave delays significantly (-0.3 to +0.5 s). Integration of these corrections into the 3-D modeling is achieved in two ways: (a) a priori adjustment to the delay time vector and (b) inverting only for anisotropic delays by introducing strong damping above 80 km and below 360 km depths and then subtracting the obtained anisotropic artifact image from the isotropic image, to get the corrected image. Under the assumption of azimuthal anisotropy resulting from lattice preferred orientation (LPO) alignment due to horizontal flow, the bias in isotropic P wave tomographic images is clear. The anisotropy corrected velocity perturbations are in the range of ±1.2% at depths of around 150 km and reduced further at deeper levels. Although the bias due to anisotropy does not affect the gross features, it does introduce certain artifacts at deeper levels.

  11. Enhanced Sensitivity of Surface Acoustic Wave-Based Rate Sensors Incorporating Metallic Dot Arrays

    PubMed Central

    Wang, Wen; Shao, Xiuting; Liu, Xinlu; Liu, Jiuling; He, Shitang

    2014-01-01

    A new surface acoustic wave (SAW)-based rate sensor pattern incorporating metallic dot arrays was developed in this paper. Two parallel SAW delay lines with a reverse direction and an operation frequency of 80 MHz on a same X-112°Y LiTaO3 wafer are fabricated as the feedback of two SAW oscillators, and mixed oscillation frequency was used to characterize the external rotation. To enhance the Coriolis force effect acting on the SAW propagation, a copper (Cu) dot array was deposited along the SAW propagation path of the SAW devices. The approach of partial-wave analysis in layered media was referred to analyze the response mechanisms of the SAW based rate sensor, resulting in determination of the optimal design parameters. To improve the frequency stability of the oscillator, the single phase unidirectional transducers (SPUDTs) and combed transducer were used to form the SAW device to minimize the insertion loss and accomplish the single mode selection, respectively. Excellent long-term (measured in hours) frequency stability of 0.1 ppm/h was obtained. Using the rate table with high precision, the performance of the developed SAW rate sensor was evaluated experimentally; satisfactory detection sensitivity (16.7 Hz·deg·s−1) and good linearity were observed. PMID:24577520

  12. Calculation of enhanced slowing and cooling due to the addition of a traveling wave to an intense optical standing wave

    NASA Astrophysics Data System (ADS)

    Gottesman, D.; Mervis, J.; Prentiss, M.; Bigelow, N. P.

    1992-07-01

    We investigate the force on a two-level atom interacting with intense monochromatic laser fields which are combinations of standing and traveling waves. We present a continued-fraction solution to the optical Bloch equations. Using this solution to calculate the force on an atom, we have examined the slowing and cooling of a thermal Na atomic beam. We find that the addition of a traveling wave to an intense standing wave can significantly improve the slowing rate and simultaneously decrease the final velocity of the cooled beam.

  13. Aluminum bioavailability from basic sodium aluminum phosphate, an approved food additive emulsifying agent, incorporated in cheese.

    PubMed

    Yokel, Robert A; Hicks, Clair L; Florence, Rebecca L

    2008-06-01

    Oral aluminum (Al) bioavailability from drinking water has been previously estimated, but there is little information on Al bioavailability from foods. It was suggested that oral Al bioavailability from drinking water is much greater than from foods. The objective was to further test this hypothesis. Oral Al bioavailability was determined in the rat from basic [26Al]-sodium aluminum phosphate (basic SALP) in a process cheese. Consumption of approximately 1g cheese containing 1.5% or 3% basic SALP resulted in oral Al bioavailability (F) of approximately 0.1% and 0.3%, respectively, and time to maximum serum 26Al concentration (Tmax) of 8-9h. These Al bioavailability results were intermediate to previously reported results from drinking water (F approximately 0.3%) and acidic-SALP incorporated into a biscuit (F approximately 0.1%), using the same methods. Considering the similar oral bioavailability of Al from food vs. water, and their contribution to the typical human's daily Al intake ( approximately 95% and 1.5%, respectively), these results suggest food contributes much more Al to systemic circulation, and potential Al body burden, than does drinking water. These results do not support the hypothesis that drinking water provides a disproportionate contribution to total Al absorbed from the gastrointestinal tract.

  14. Incorporating clonal growth form clarifies the role of plant height in response to nitrogen addition.

    PubMed

    Gough, Laura; Gross, Katherine L; Cleland, Elsa E; Clark, Christopher M; Collins, Scott L; Fargione, Joseph E; Pennings, Steven C; Suding, Katharine N

    2012-08-01

    Nutrient addition to grasslands consistently causes species richness declines and productivity increases. Competition, particularly for light, is often assumed to produce this result. Using a long-term dataset from North American herbaceous plant communities, we tested whether height and clonal growth form together predict responses to fertilization because neither trait alone predicted species loss in a previous analysis. Species with a tall-runner growth form commonly increased in relative abundance in response to added nitrogen, while short species and those with a tall-clumped clonal growth form often decreased. The ability to increase in size via vegetative spread across space, while simultaneously occupying the canopy, conferred competitive advantage, although typically only the abundance of a single species within each height-clonal growth form significantly responded to fertilization in each experiment. Classifying species on the basis of two traits (height and clonal growth form) increases our ability to predict species responses to fertilization compared to either trait alone in predominantly herbaceous plant communities. Electronic supplementary material The online version of this article (doi:10.1007/s00442-012-2264-5) contains supplementary material, which is available to authorized users.

  15. Imaging the lithosphere beneath NE Tibet: teleseismic P and S body wave tomography incorporating surface wave starting models

    NASA Astrophysics Data System (ADS)

    Nunn, Ceri; Roecker, Steven W.; Tilmann, Frederik J.; Priestley, Keith F.; Heyburn, Ross; Sandvol, Eric A.; Ni, James F.; Chen, Yongshun John; Zhao, Wenjin; Team, The Indepth

    2014-03-01

    The northeastern margin of the Tibetan Plateau, which includes the Qiangtang and Songpan-Ganzi terranes as well as the Kunlun Shan and the Qaidam Basin, continues to deform in response to the ongoing India-Eurasia collision. To test competing hypotheses concerning the mechanisms for this deformation, we assembled a high-quality data set of approximately 14 000 P- and 4000 S-wave arrival times from earthquakes at teleseismic distances from the International Deep Profiling of Tibet and the Himalaya, Phase IV broad-band seismometer deployments. We analyse these arrival times to determine tomographic images of P- and S-wave velocities in the upper mantle beneath this part of the plateau. To account for the effects of major heterogeneity in crustal and uppermost mantle wave velocities in Tibet, we use recent surface wave models to construct a starting model for our teleseismic body wave inversion. We compare the results from our model with those from simpler starting models, and find that while the reduction in residuals and results for deep structure are similar between models, the results for shallow structure are different. Checkerboard tests indicate that features of ˜125 km length scale are reliably imaged throughout the study region. Using synthetic tests, we show that the best recovery is below ˜300 km, and that broad variations in shallow structure can also be recovered. We also find that significant smearing can occur, especially at the edges of the model. We observe a shallow dipping seismically fast structure at depths of ˜140-240 km, which dies out gradually between 33°N and 35°N. Based on the lateral continuity of this structure (from the surface waves) we interpret it as Indian lithosphere. Alternatively, the entire area could be thickened by pure shear, or the northern part could be an underthrust Lhasa Terrane lithospheric slab with only the southern part from India. We see a deep fast wave velocity anomaly (below 300 km), that is consistent with

  16. Incorporating fault zone head wave and direct wave secondary arrival times into seismic tomography: Application at Parkfield, California

    NASA Astrophysics Data System (ADS)

    Bennington, Ninfa L.; Thurber, Clifford; Peng, Zhigang; Zhang, Haijiang; Zhao, Peng

    2013-03-01

    We present a three-dimensional (3D) P wave velocity (Vp) model of the Parkfield region that utilizes existing P wave arrival time data, including fault zone head waves (FZHWs), and data from direct wave secondary arrivals (DWSAs). The first-arrival and DWSA travel times are obtained as the global- and local-minimum travel time paths, respectively. The inclusion of FZHWs and DWSAs results in as much as a 5% and a 10% increase in the across-fault velocity contrast, respectively, for the Vp model at Parkfield relative to that of Thurber et al. [2006]. Viewed along strike, three pronounced velocity contrast regions are observed: a pair of strong positive velocity contrasts (SW fast), one NW of the 1966 Parkfield earthquake hypocenter and the other SE of the 2004 Parkfield earthquake hypocenter, and a strong negative velocity contrast (NE fast) between the two hypocenters. The negative velocity contrast partially to entirely encompasses peak coseismic slip estimated in several slip models for the 2004 earthquake, suggesting that the negative velocity contrast played a part in defining the rupture patch of the 2004 Parkfield earthquake. Following Ampuero and Ben-Zion (2008), the pattern of velocity contrasts is consistent with the observed bilateral rupture propagation for the 2004 Parkfield earthquake. Although the velocity contrasts also suggest bilateral rupture propagation for the 1966 Parkfield earthquake, the fault is creeping to the NW here, i.e., exhibiting velocity-strengthening behavior. Thus, it is not surprising that rupture propagated only SE during this event.

  17. Effects of Incorporation Method of Ethoprop and Addition of Aldicarb on Potato Tuber Infection by Meloidogyne hapla

    PubMed Central

    Ingham, Russell E.; Morris, Mark; Newcomb, Gene B.

    1991-01-01

    The efficacy of controlling Meloidogyne hapla on potato with water incorporation of ethoprop was compared to physical incorporation before planting. The standard practice of aldicarb application for insect control was also evaluated for M. hapla suppression with and without ethoprop. Physical incorporation before planting by rototilling or discing reduced (P ≤ 0.05) tuber infection. Postplant water incorporation of ethoprop was not as effective as physical incorporation of ethoprop or postplant water incorporation of aldicarb and did not reduce (P ≤ 0.05) tuber infection at harvest. Ethoprop did not affect yield, whereas aldicarb increased yield in one experiment. PMID:19283186

  18. Remarkable enhancement of charge carrier mobility of conjugated polymer field-effect transistors upon incorporating an ionic additive

    PubMed Central

    Luo, Hewei; Yu, Chenmin; Liu, Zitong; Zhang, Guanxin; Geng, Hua; Yi, Yuanping; Broch, Katharina; Hu, Yuanyuan; Sadhanala, Aditya; Jiang, Lang; Qi, Penglin; Cai, Zhengxu; Sirringhaus, Henning; Zhang, Deqing

    2016-01-01

    Organic semiconductors with high charge carrier mobilities are crucial for flexible electronic applications. Apart from designing new conjugated frameworks, different strategies have been explored to increase charge carrier mobilities. We report a new and simple approach to enhancing the charge carrier mobility of DPP-thieno[3,2-b]thiophene–conjugated polymer by incorporating an ionic additive, tetramethylammonium iodide, without extra treatments into the polymer. The resulting thin films exhibit a very high hole mobility, which is higher by a factor of 24 than that of thin films without the ionic additive under the same conditions. On the basis of spectroscopic grazing incidence wide-angle x-ray scattering and atomic force microscopy studies as well as theoretical calculations, the remarkable enhancement of charge mobility upon addition of tetramethylammonium iodide is attributed primarily to an inhibition of the torsion of the alkyl side chains by the presence of the ionic species, facilitating a more ordered lamellar packing of the alkyl side chains and interchain π-π interactions. PMID:27386541

  19. Remarkable enhancement of charge carrier mobility of conjugated polymer field-effect transistors upon incorporating an ionic additive.

    PubMed

    Luo, Hewei; Yu, Chenmin; Liu, Zitong; Zhang, Guanxin; Geng, Hua; Yi, Yuanping; Broch, Katharina; Hu, Yuanyuan; Sadhanala, Aditya; Jiang, Lang; Qi, Penglin; Cai, Zhengxu; Sirringhaus, Henning; Zhang, Deqing

    2016-05-01

    Organic semiconductors with high charge carrier mobilities are crucial for flexible electronic applications. Apart from designing new conjugated frameworks, different strategies have been explored to increase charge carrier mobilities. We report a new and simple approach to enhancing the charge carrier mobility of DPP-thieno[3,2-b]thiophene-conjugated polymer by incorporating an ionic additive, tetramethylammonium iodide, without extra treatments into the polymer. The resulting thin films exhibit a very high hole mobility, which is higher by a factor of 24 than that of thin films without the ionic additive under the same conditions. On the basis of spectroscopic grazing incidence wide-angle x-ray scattering and atomic force microscopy studies as well as theoretical calculations, the remarkable enhancement of charge mobility upon addition of tetramethylammonium iodide is attributed primarily to an inhibition of the torsion of the alkyl side chains by the presence of the ionic species, facilitating a more ordered lamellar packing of the alkyl side chains and interchain π-π interactions.

  20. Remarkable enhancement of charge carrier mobility of conjugated polymer field-effect transistors upon incorporating an ionic additive.

    PubMed

    Luo, Hewei; Yu, Chenmin; Liu, Zitong; Zhang, Guanxin; Geng, Hua; Yi, Yuanping; Broch, Katharina; Hu, Yuanyuan; Sadhanala, Aditya; Jiang, Lang; Qi, Penglin; Cai, Zhengxu; Sirringhaus, Henning; Zhang, Deqing

    2016-05-01

    Organic semiconductors with high charge carrier mobilities are crucial for flexible electronic applications. Apart from designing new conjugated frameworks, different strategies have been explored to increase charge carrier mobilities. We report a new and simple approach to enhancing the charge carrier mobility of DPP-thieno[3,2-b]thiophene-conjugated polymer by incorporating an ionic additive, tetramethylammonium iodide, without extra treatments into the polymer. The resulting thin films exhibit a very high hole mobility, which is higher by a factor of 24 than that of thin films without the ionic additive under the same conditions. On the basis of spectroscopic grazing incidence wide-angle x-ray scattering and atomic force microscopy studies as well as theoretical calculations, the remarkable enhancement of charge mobility upon addition of tetramethylammonium iodide is attributed primarily to an inhibition of the torsion of the alkyl side chains by the presence of the ionic species, facilitating a more ordered lamellar packing of the alkyl side chains and interchain π-π interactions. PMID:27386541

  1. The incorporation of fault zone head wave and direct wave secondary arrival times and arrival polarizations into seismic tomography: Application to the Parkfield, California area

    NASA Astrophysics Data System (ADS)

    Bennington, N. L.; Thurber, C. H.; Peng, Z.; Zhao, P.

    2012-12-01

    We present a 3D P-wave velocity (Vp) model of the Parkfield region that utilizes existing P-wave arrival time data, including fault zone head waves (FZHW), plus new data from direct wave secondary arrivals (DWSA). The first-arrival and DWSA travel times are obtained as the global and local minimum travel time paths, respectively. The inclusion of DWSA results in as much as a 10% increase in the across-fault velocity contrast for the Vp model at Parkfield relative to Thurber et al. (2006). Viewed along strike, three pronounced velocity contrast regions are observed: a pair of strong positive velocity contrasts (SW fast), one NW of the 1966 Parkfield hypocenter and the other SE of the 2004 Parkfield hypocenter, and a strong negative velocity contrast (NE fast) between the two hypocenters. The negative velocity contrast partially to entirely encompasses peak coseismic slip estimated in several slip models for the 2004 earthquake, suggesting that the negative velocity contrast played a part in defining the rupture patch of the 2004 Parkfield earthquake. We expand on this work by modifying our seismic tomography algorithm to incorporate arrival polarizations (azimuths). Synthetic tests will be presented to demonstrate the improvements in velocity structure when arrival polarizations are incorporated. These tests will compare the synthetic model recovered when FZHW/DWSA arrivals as well as existing P-wave arrival time data are inverted to that recovered with the same dataset with the inclusion of arrival polarizations. We plan to extend this work to carry out a full scale seismic tomography/relocation inversion at Parkfield, CA utilizing arrival polarizations from all first-P arrivals, and FZHW/DWSA arrivals as well as existing P-wave arrival time data. This effort requires the determination of polarization data for all P-waves and FZHW's at Parkfield. To this end, we use changes in the arrival azimuth from fault normal to source-receiver direction to identify FZHW and

  2. Dynamic mechanical properties of a maxillofacial silicone elastomer incorporating a ZnO additive: the effect of artificial aging.

    PubMed

    Mouzakis, Dionysios E; Papadopoulos, Triantafillos D; Polyzois, Gregory L; Griniari, Panagiota G

    2010-11-01

    The main objective of the current study was to investigate the dynamic mechanical properties of a room-temperature vulcanizing silicone incorporating different fractions of zinc oxide (ZnO) after indoor and outdoor photoaging. Forty-eight samples were produced by adding different amounts of ZnO into a commercial maxillofacial silicone (EPISIL-E). The samples were divided into 4 groups containing 0.0, 0.2, 0.5, and 1 wt% ZnO additive, respectively. Samples were exposed to sunlight (subgroup 2), ultraviolet (subgroup 3), and fluorescence (subgroup 4) aging, whereas nonaged samples comprised the control subgroup (subgroup 1). Dynamic mechanical analysis was used to determine the storage modulus (E'), loss modulus (E″), and damping capacity (tanδ). General linear statistic model was conducted to evaluate the effects of aging, testing frequency, and composition on the dynamic mechanical properties of the silicone with the ZnO additive. Post hoc analysis was performed using Tukey test. Statistical analysis revealed a significant impact of composition on tanδ (P < 0.05). Aging influenced E' and E″ (P < 0.01). The combination of aging and composition had a significant effect on all dynamic properties (P < 0.01).

  3. Dynamic mechanical properties of a maxillofacial silicone elastomer incorporating a ZnO additive: the effect of artificial aging.

    PubMed

    Mouzakis, Dionysios E; Papadopoulos, Triantafillos D; Polyzois, Gregory L; Griniari, Panagiota G

    2010-11-01

    The main objective of the current study was to investigate the dynamic mechanical properties of a room-temperature vulcanizing silicone incorporating different fractions of zinc oxide (ZnO) after indoor and outdoor photoaging. Forty-eight samples were produced by adding different amounts of ZnO into a commercial maxillofacial silicone (EPISIL-E). The samples were divided into 4 groups containing 0.0, 0.2, 0.5, and 1 wt% ZnO additive, respectively. Samples were exposed to sunlight (subgroup 2), ultraviolet (subgroup 3), and fluorescence (subgroup 4) aging, whereas nonaged samples comprised the control subgroup (subgroup 1). Dynamic mechanical analysis was used to determine the storage modulus (E'), loss modulus (E″), and damping capacity (tanδ). General linear statistic model was conducted to evaluate the effects of aging, testing frequency, and composition on the dynamic mechanical properties of the silicone with the ZnO additive. Post hoc analysis was performed using Tukey test. Statistical analysis revealed a significant impact of composition on tanδ (P < 0.05). Aging influenced E' and E″ (P < 0.01). The combination of aging and composition had a significant effect on all dynamic properties (P < 0.01). PMID:21119441

  4. Control of terahertz emission in photoconductive antennas through an additional optical continuous wave.

    PubMed

    Bockelt, A; Palací, J; Vidal, B

    2013-08-15

    The manipulation of the operating conditions of photoconductive antennas by means of an additional continuous wave (CW) is reported. It is used to control a fiber-based terahertz (THz) time-domain-spectroscopy system at telecom wavelengths. The injection of an optical CW into the transmitter allows the control of the THz amplitude without causing major degradation to the system performance. This, for instance, can be exploited to perform modulation of the THz signal. PMID:24104665

  5. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  6. Incorporating Love- and Rayleigh-wave magnitudes, unequal earthquake and explosion variance assumptions and interstation complexity for improved event screening

    SciTech Connect

    Anderson, Dale N; Bonner, Jessie L; Stroujkova, Anastasia; Shumway, Robert

    2009-01-01

    Our objective is to improve seismic event screening using the properties of surface waves, We are accomplishing this through (1) the development of a Love-wave magnitude formula that is complementary to the Russell (2006) formula for Rayleigh waves and (2) quantifying differences in complexities and magnitude variances for earthquake and explosion-generated surface waves. We have applied the M{sub s} (VMAX) analysis (Bonner et al., 2006) using both Love and Rayleigh waves to events in the Middle East and Korean Peninsula, For the Middle East dataset consisting of approximately 100 events, the Love M{sub s} (VMAX) is greater than the Rayleigh M{sub s} (VMAX) estimated for individual stations for the majority of the events and azimuths, with the exception of the measurements for the smaller events from European stations to the northeast. It is unclear whether these smaller events suffer from magnitude bias for the Love waves or whether the paths, which include the Caspian and Mediterranean, have variable attenuation for Love and Rayleigh waves. For the Korean Peninsula, we have estimated Rayleigh- and Love-wave magnitudes for 31 earthquakes and two nuclear explosions, including the 25 May 2009 event. For 25 of the earthquakes, the network-averaged Love-wave magnitude is larger than the Rayleigh-wave estimate. For the 2009 nuclear explosion, the Love-wave M{sub s} (VMAX) was 3.1 while the Rayleigh-wave magnitude was 3.6. We are also utilizing the potential of observed variances in M{sub s} estimates that differ significantly in earthquake and explosion populations. We have considered two possible methods for incorporating unequal variances into the discrimination problem and compared the performance of various approaches on a population of 73 western United States earthquakes and 131 Nevada Test Site explosions. The approach proposes replacing the M{sub s} component by M{sub s} + a* {sigma}, where {sigma} denotes the interstation standard deviation obtained from the

  7. Incorporating floating surface objects into a fully dispersive surface wave model

    NASA Astrophysics Data System (ADS)

    Orzech, Mark D.; Shi, Fengyan; Veeramony, Jayaram; Bateman, Samuel; Calantoni, Joseph; Kirby, James T.

    2016-06-01

    The shock-capturing, non-hydrostatic, three-dimensional (3D) finite-volume model NHWAVE was originally developed to simulate wave propagation and landslide-generated tsunamis in finite water depth (Ma, G., Shi, F., Kirby, J. T., 2012. Ocean Model. 43-44, 22-35). The model is based on the incompressible Navier-Stokes equations, in which the z-axis is transformed to a σ-coordinate that tracks the bed and surface. As part of an ongoing effort to simulate waves in polar marginal ice zones (MIZs), the model has now been adapted to allow objects of arbitrary shape and roughness to float on or near its water surface. The shape of the underside of each floating object is mapped onto an upper σ-level slightly below the surface. In areas without floating objects, this σ-level continues to track the surface and bed as before. Along the sides of each floating object, an immersed boundary method is used to interpolate the effects of the object onto the neighboring fluid volume. Provided with the object's shape, location, and velocity over time, NHWAVE determines the fluid fluxes and pressure variations from the corresponding accelerations at neighboring cell boundaries. The system was validated by comparison with analytical solutions and a VOF model for a 2D floating box and with laboratory measurements of wave generation by a vertically oscillating sphere. A steep wave simulation illustrated the high efficiency of NHWAVE relative to a VOF model. In a more realistic MIZ simulation, the adapted model produced qualitatively reasonable results for wave attenuation, diffraction, and scattering.

  8. Attenuation of electromagnetic wave propagation in sandstorms incorporating charged sand particles

    NASA Astrophysics Data System (ADS)

    Zhou, You-He; Shu He, Qin; Zheng, Xiao Jing

    2005-06-01

    A theoretical approach for predicting the attenuation of microwave propagation in sandstorms is presented, with electric charges generated on the sand grains taken into account. It is found that the effect of electric charges distributed partially on the sand surface is notable. The calculated attenuation is in good agreement with that measured in certain conditions. The distribution of electric charges on the surface of sand grains, which is not easy to measure, can be approximately determined by measuring the attenuation value of electromagnetic waves. Some effects of sand radius, dielectric permittivity, frequency of electromagnetic wave, and visibility of sandstorms on the attenuation are also discussed quantitatively. Finally, a new electric parameter is introduced to describe the roles of scattering, absorption and effect of charges in attenuation.

  9. A theoretical study of wave dispersion and thermal conduction for HMX/additive interfaces

    NASA Astrophysics Data System (ADS)

    Long, Yao; Chen, Jun

    2014-04-01

    The wave dispersion rule for non-uniform material is useful for ultrasonic inspection and engine life prediction, and also is key in achieving an understanding of the energy dissipation and thermal conduction properties of solid material. On the basis of linear response theory and molecular dynamics, we derive a set of formulas for calculating the wave dispersion rate of interface systems, and study four kinds of interfaces inside plastic bonded explosives: HMX/{HMX, TATB, F2312, F2313}. (HMX: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; TATB: 1,3,5-triamino-2,4,6-trinitrobenzene; F2312, F2313: fluoropolymers). The wave dispersion rate is obtained over a wide frequency range from kHz to PHz. We find that at low frequency, the rate is proportional to the square of the frequency, and at high frequency, the rate couples with the molecular vibration modes at the interface. By using the results, the thermal conductivities of HMX/additive interfaces are derived, and a physical model is built for describing the total thermal conductivity of mixture explosives, including HMX multi-particle systems and {TATB, F2312, F2313}-coated HMX.

  10. Effect of incorporating carbon nanocoils on the efficiency of electromagnetic-wave shielding of carbon-nanomaterial composites

    NASA Astrophysics Data System (ADS)

    Kang, Gi-Hwan; Kim, Sung-Hoon

    2016-09-01

    Carbon nanocoils (CNCs) were deposited on Al2O3 substrates using C2H2 and H2 as source gases in a thermal chemical vapor deposition system. Composites of CNCs in polyurethane (CNC@PU) and CNCs plus other carbon-based materials, such as carbon microcoils (CMCs) and carbon nanotubes (CNTs), in polyurethane (CNC + CMC@PU, CNC + CNT@PU) was fabricated. The electromagnetic-wave-shielding effectiveness of the CNCs-incorporated composites were examined and compared with those of other carbon-based materials in the measurement-frequency range of 0.25-4.0 GHz. The incorporation of CNCs in CMC@PU composites reduced the shielding effectiveness; on the other hand, it slightly enhanced the shielding effectiveness of CNT@PU composites within the measurement frequency range of 0.5-3.0 GHz. Based on the resulting shielding effectiveness, we conclude that the incorporation of CNCs was useful for the materials that exhibited reflection-based shielding effectiveness although the CNCs themselves had poor electrical conductivity.

  11. Auxiliary Lagrangian and Conservation Laws for a Wave Equation Incorporating Dissipation

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Wei, Long

    2015-04-01

    In this work we study the Lagrangian and the conservation laws for a wave equation with a dissipative source. Using semi-inverse method, we show that the equation possesses a nonlocal Lagrangian with an auxiliary function. As a result, from a modified Noether's theorem and the nonclassical Noether symmetry generators, we construct some conservation laws for this equation, which are different from the ones obtained by Ibragimov's theorem in [Y. Wang and L. Wei, Abstr. App. Anal. 2013 (2013) 407908]. The results show that our method work for arbitrary functions f(u) and g(u) rather than special ones. Supported by National Natural Science Foundation of China under Grant No. 11101111, and Zhejiang Provincial Natural Science Foundation of China under Grant Nos. LY14A010029 and LY12A01003

  12. Methods and apparatus of suppressing tube waves within a bore hole and seismic surveying systems incorporating same

    DOEpatents

    West, Phillip B.; Haefner, Daryl

    2005-12-13

    Methods and apparatus for attenuating waves in a bore hole, and seismic surveying systems incorporating the same. In one embodiment, an attenuating device includes a soft compliant bladder coupled to a pressurized gas source. A pressure regulating system reduces the pressure of the gas from the gas source prior to entering the bladder and operates in conjunction with the hydrostatic pressure of the fluid in a bore hole to maintain the pressure of the bladder at a specified pressure relative to the surrounding bore hole pressure. Once the hydrostatic pressure of the bore hole fluid exceeds that of the gas source, bore hole fluid may be admitted into a vessel of the gas source to further compress and displace the gas contained therein. In another embodiment, a water-reactive material may be used to provide gas to the bladder wherein the amount of gas generated by the water-reactive material may depend on the hydrostatic pressure of the bore hole fluid.

  13. Methods and apparatus of suppressing tube waves within a bore hole and seismic surveying systems incorporating same

    DOEpatents

    West, Phillip B.; Haefner, Daryl

    2004-08-17

    Methods and apparatus for attenuating waves in a bore hole, and seismic surveying systems incorporating the same. In one embodiment, an attenuating device includes a soft compliant bladder coupled to a pressurized gas source. A pressure regulating system reduces the pressure of the gas from the gas source prior to entering the bladder and operates in conjunction with the hydrostatic pressure of the fluid in a bore hole to maintain the pressure of the bladder at a specified pressure relative to the surrounding bore hole pressure. Once the hydrostatic pressure of the bore hole fluid exceeds that of the gas source, bore hole fluid may be admitted into a vessel of the gas source to further compress and displace the gas contained therein. In another embodiment, a water-reactive material may be used to provide gas to the bladder wherein the amount of gas generated by the water-reactive material may depend on the hydrostatic pressure of the bore hole fluid.

  14. Mass Sensitivity Optimization of a Surface Acoustic Wave Sensor Incorporating a Resonator Configuration

    PubMed Central

    Hao, Wenchang; Liu, Jiuling; Liu, Minghua; Liang, Yong; He, Shitang

    2016-01-01

    The effect of the sensitive area of the two-port resonator configuration on the mass sensitivity of a Rayleigh surface acoustic wave (R-SAW) sensor was investigated theoretically, and verified in experiments. A theoretical model utilizing a 3-dimensional finite element method (FEM) approach was established to extract the coupling-of-modes (COM) parameters in the absence and presence of mass loading covering the electrode structures. The COM model was used to simulate the frequency response of an R-SAW resonator by a P-matrix cascading technique. Cascading the P-matrixes of unloaded areas with mass loaded areas, the sensitivity for different sensitive areas was obtained by analyzing the frequency shift. The performance of the sensitivity analysis was confirmed by the measured responses from the silicon dioxide (SiO2) deposited on different sensitive areas of R-SAW resonators. It is shown that the mass sensitivity varies strongly for different sensitive areas, and the optimal sensitive area lies towards the center of the device. PMID:27104540

  15. DNA--a molecule in search of additional functions: recipient of pool wave emissions? A hypothesis.

    PubMed

    Doerfler, Walter

    2010-09-01

    Almost the entire nucleotide sequence of human DNA is functionally unaccounted for, although large parts of the human genome are transcribed. The genes, as defined by current molecular biology, comprise about 1.5-2% of the DNA molecule. It is proposed that DNA encodes additional, hitherto unrecognized functions. In this discussion, the total information inside and outside the universe we live in is termed the pool or the sum total, known or unknown, of all laws, matter, energy, concepts and events. In a hypothetical model, a Gedankenexperiment, it is suggested that the total of all information emits pool waves of an unknown physical nature. They could be related to black energy or have completely different qualities. The designation pool waves should not imply any similarity to electromagnetism. Further, DNA is suggested to have the capability of interacting with the pool waves and thus permit humans - to some partly genetically determined and yet very limited extent - to perceive information from the pool. Pool emissions might be one of the forces that have been instrumental in and are still driving evolution from simple oligonucleotides to DNA with ever more complex recipient capacities. It will be a major challenge for researchers in the field to unravel these and less hypothetical undetected coding principles in DNA. It is uncertain whether the current trend to search the available DNA sequences with ever more refined computer technology on the basis of our present understanding of biology will detect unknown coding systems. For molecular medicine, research into the genetics of the most common human diseases could profit from the elucidation of presently still ephemeral codes in human DNA. Young scientists with a proven record of original research deserve support for the pursuit of unconventional ideas. This concept of granting priorities will be of the utmost importance in advancing the field beyond current concepts in molecular biology.

  16. Recent Additions in the Modeling Capabilities of an Open-Source Wave Energy Converter Design Tool: Preprint

    SciTech Connect

    Tom, N.; Lawson, M.; Yu, Y. H.

    2015-04-20

    WEC-Sim is a midfidelity numerical tool for modeling wave energy conversion devices. The code uses the MATLAB SimMechanics package to solve multibody dynamics and models wave interactions using hydrodynamic coefficients derived from frequency-domain boundary-element methods. This paper presents the new modeling features introduced in the latest release of WEC-Sim. The first feature discussed conversion of the fluid memory kernel to a state-space form. This enhancement offers a substantial computational benefit after the hydrodynamic body-to-body coefficients are introduced and the number of interactions increases exponentially with each additional body. Additional features include the ability to calculate the wave-excitation forces based on the instantaneous incident wave angle, allowing the device to weathervane, as well as import a user-defined wave elevation time series. A review of the hydrodynamic theory for each feature is provided and the successful implementation is verified using test cases.

  17. Nucleophilic addition to a p-benzyne derived from an enediyne: a new mechanism for halide incorporation into biomolecules.

    PubMed

    Perrin, Charles L; Rodgers, Betsy L; O'Connor, Joseph M

    2007-04-18

    Biosynthesis of haloaromatics ordinarily occurs by electrophilic attack of an activated halogen species on an electron-rich aromatic ring. We now present the discovery of a new reaction whereby a nucleophilic halide anion can be attached even to an aromatic ring without activating substituents. We show that the enediyne cyclodeca-1,5-diyn-3-ene, in the presence of lithium halide and a weak acid, is converted to 1-halotetrahydronaphthalene. The kinetics are consistent with rate-limiting cyclization to a p-benzyne biradical that rapidly adds halide and is then protonated. This reaction has interesting mechanistic features and important implications for incorporation of halide into biomolecules.

  18. Prediction of maximum P- and S-wave amplitude distributions incorporating frequency- and distance-dependent characteristics of the observed apparent radiation patterns

    NASA Astrophysics Data System (ADS)

    Takemura, Shunsuke; Kobayashi, Manabu; Yoshimoto, Kazuo

    2016-10-01

    Frequency-dependent model of the apparent radiation pattern has been extensively incorporated into engineering and scientific applications for high-frequency seismic waves, but distance-dependent properties have not yet been fully taken into account. We investigated the unified characteristics of frequency and distance dependences in both apparent P- and S-wave radiation patterns during local crustal earthquakes. Observed distortions of the apparent P- and S-wave radiation patterns could be simply modeled by using a function of the normalized hypocentral distance, which is a product of the wave number and hypocentral distance. This behavior suggests that major cause of distortion of the apparent radiation pattern is seismic wave scattering and diffraction within the heterogeneous crust. On the basis of observed normalized hypocentral distance dependency, we proposed a method for prediction of spatial distributions of maximum P- and S-wave amplitudes. Our method incorporating normalized hypocentral distance dependence of the apparent radiation pattern reproduced the observed spatial distributions of maximum P- and S-wave amplitudes over a wide frequency and distance ranges successfully.[Figure not available: see fulltext.

  19. Screening and incorporation of rust resistance from Allium cepa into bunching onion (Allium fistulosum) via alien chromosome addition.

    PubMed

    Wako, Tadayuki; Yamashita, Ken-ichiro; Tsukazaki, Hikaru; Ohara, Takayoshi; Kojima, Akio; Yaguchi, Shigenori; Shimazaki, Satoshi; Midorikawa, Naoko; Sakai, Takako; Yamauchi, Naoki; Shigyo, Masayoshi

    2015-04-01

    Bunching onion (Allium fistulosum L.; 2n = 16), bulb onion (Allium cepa L. Common onion group), and shallot (Allium cepa L. Aggregatum group) cultivars were inoculated with rust fungus, Puccinia allii, isolated from bunching onion. Bulb onions and shallots are highly resistant to rust, suggesting they would serve as useful resources for breeding rust resistant bunching onions. To identify the A. cepa chromosome(s) related to rust resistance, a complete set of eight A. fistulosum - shallot monosomic alien addition lines (MAALs) were inoculated with P. allii. At the seedling stage, FF+1A showed a high level of resistance in controlled-environment experiments, suggesting that the genes related to rust resistance could be located on shallot chromosome 1A. While MAAL, multi-chromosome addition line, and hypoallotriploid adult plants did not exhibit strong resistance to rust. In contrast to the high resistance of shallot, the addition line FF+1A+5A showed reproducibly high levels of rust resistance.

  20. Ameliorative effects of telmisartan on the inflammatory response and impaired spatial memory in a rat model of Alzheimer's disease incorporating additional cerebrovascular disease factors.

    PubMed

    Shindo, Taro; Takasaki, Kotaro; Uchida, Kanako; Onimura, Rika; Kubota, Kaori; Uchida, Naoki; Irie, Keiichi; Katsurabayashi, Shutaro; Mishima, Kenichi; Nishimura, Ryoji; Fujiwara, Michihiro; Iwasaki, Katsunori

    2012-01-01

    Telmisartan, an angiotensin type 1 receptor blocker, is used in the management of hypertension to control blood pressure. In addition, telmisartan has a partial agonistic effect on peroxisome proliferator activated receptor γ (PPARγ). Recently, the effects of telmisartan on spatial memory or the inflammatory response were monitored in a mouse model of Alzheimer's disease (AD). However, to date, no studies have investigated the ameliorative effects of telmisartan on impaired spatial memory and the inflammatory response in an AD animal model incorporating additional cerebrovascular disease factors. In this study, we examined the effect of telmisartan on spatial memory impairment and the inflammatory response in a rat model of AD incorporating additional cerebrovascular disease factors. Rats were subjected to cerebral ischemia and an intracerebroventricular injection of oligomeric or aggregated amyloid-β (Aβ). Oral administration of telmisartan (0.3, 1, 3 mg/kg/d) seven days after ischemia and Aβ treatment resulted in better performance in the eight arm radial maze task in a dose-dependent manner. Telmisartan also reduced tumor necrosis factor α mRNA expression in the hippocampal region of rats with impaired spatial memory. These effects of telmisartan were antagonized by GW9662, an antagonist of PPARγ. These results suggest that telmisartan has ameliorative effects on the impairment of spatial memory in a rat model of AD incorporating additional cerebrovascular disease factors via its anti-inflammatory effect.

  1. Screening and incorporation of rust resistance from Allium cepa into bunching onion (Allium fistulosum) via alien chromosome addition.

    PubMed

    Wako, Tadayuki; Yamashita, Ken-ichiro; Tsukazaki, Hikaru; Ohara, Takayoshi; Kojima, Akio; Yaguchi, Shigenori; Shimazaki, Satoshi; Midorikawa, Naoko; Sakai, Takako; Yamauchi, Naoki; Shigyo, Masayoshi

    2015-04-01

    Bunching onion (Allium fistulosum L.; 2n = 16), bulb onion (Allium cepa L. Common onion group), and shallot (Allium cepa L. Aggregatum group) cultivars were inoculated with rust fungus, Puccinia allii, isolated from bunching onion. Bulb onions and shallots are highly resistant to rust, suggesting they would serve as useful resources for breeding rust resistant bunching onions. To identify the A. cepa chromosome(s) related to rust resistance, a complete set of eight A. fistulosum - shallot monosomic alien addition lines (MAALs) were inoculated with P. allii. At the seedling stage, FF+1A showed a high level of resistance in controlled-environment experiments, suggesting that the genes related to rust resistance could be located on shallot chromosome 1A. While MAAL, multi-chromosome addition line, and hypoallotriploid adult plants did not exhibit strong resistance to rust. In contrast to the high resistance of shallot, the addition line FF+1A+5A showed reproducibly high levels of rust resistance. PMID:26218854

  2. Incorporation of 210Pb and 210Po to Poultry through the Addition of Dicalcium Phosphate (DCP) to the Diet

    NASA Astrophysics Data System (ADS)

    Casacuberta, N.; Masqué, P.; Garcia-Orellana, J.; Gasa, J.; Anguita, M.

    2008-08-01

    Due to the replacement of calcium by uranium in the phosphorite, sedimentary phosphate rock contains high concentrations of 238U (i.e. from 1500 Bqṡkg-1 in Morocco to 4000 Bqṡkg-1 in Tanzania ores). Dicalcium Phosphate (DCP) is produced by the wet acid digestion of the phosphorite, and is used as a source of calcium and phosphorus for livestock feed supplement. If the phosphorite acid digestion is made with hydrochloric acid, DCP may present specific activities of about 103 Bqṡkg-1 of 238U and some of its decay chain daughters. In particular, due to its radiological implications, the presence of 210Pb and 210Po in DCP is of special relevance. The aim of this work was to investigate the potential incorporation of these radionuclides to poultry through its diet. Three different diets were therefore prepared with different contents of both DCP and 210Pb and 210Po. Diet A was used as a blank, and had a 2.5% in weight of monocalcium phosphate (MCP); diet B, with a 5% in weight of DCP; and diet C, with a 2.5% of DCP. Concentrations of 210Pb were 0.93, 101.4 and 51.2 Bqṡkg-1; whereas concentrations of 210Po were 0.92, 74 and 36 Bqṡkg-1 of food for diets A, B and C, respectively. Accumulation of 210Pb and 210Po was analysed at several times during poultry growth in samples of bone, liver, kidney, muscle, excrements as well as entire animals, with a total of 30 broilers fed with the 3 different diets. Results showed clear enhancements in the accumulation of both 210Pb and 210Po in chicken for diets B and C, and in particular in liver and bone. However, total accumulation of radionuclides in chicken, and especially in edible parts, is low compared to its expulsion through excrements. These results are interpreted in terms of the potential dose through consumption of chicken.

  3. Optimization of microwave heating in an existing cubicle cavity by incorporating additional wave guide and control components

    SciTech Connect

    Erle, R.R.; Eschen, V.G.; Sprenger, G.S.

    1995-04-01

    The use of microwave energy to thermally treat Low Level (LLW), Transuranic (TRU), and mixed waste has been under development at the Rocky Flats Environmental Technology Site (Site) since 1986. During that time, the technology has progressed from bench-scale tests, through pilot-scale tests, and finally to a full-scale demonstration unit. Experimental operations have been conducted on a variety of non-radioactive surrogates and actual radioactive waste forms. Through these studies and development efforts, the Microwave Vitrification Engineering Team (MVET) at Rocky Flats has successfully proven the application of microwave energy for waste treatment operations. In the microwave solidification process, microwave energy is used to heat a mixture of waste and glass frit to produce a vitrified product that meets all the current acceptance criteria at the final disposal sites. All of the development to date has utilized a multi-mode microwave system to provide the energy to treat the materials. Currently, evaluations are underway on modifications to the full-scale demonstration system that provide a single-mode operation as a possible method to optimize the system. This poster presentation describes the modifications made to allow the single-mode operation.

  4. Resonance scattering and radiation force calculations for an elastic cylinder using the translational addition theorem for cylindrical wave functions

    SciTech Connect

    Mitri, F. G.

    2015-09-15

    The standard Resonance Scattering Theory (RST) of plane waves is extended for the case of any two-dimensional (2D) arbitrarily-shaped monochromatic beam incident upon an elastic cylinder with arbitrary location using an exact methodology based on Graf’s translational addition theorem for the cylindrical wave functions. The analysis is exact as it does not require numerical integration procedures. The formulation is valid for any cylinder of finite size and material that is immersed in a nonviscous fluid. Partial-wave series expansions (PWSEs) for the incident, internal and scattered linear pressure fields are derived, and the analysis is further extended to obtain generalized expressions for the on-axis and off-axis acoustic radiation force components. The wave-fields are expressed using generalized PWSEs involving the beam-shape coefficients (BSCs) and the scattering coefficients of the cylinder. The off-axial BSCs are expressed analytically in terms of an infinite PWSE with emphasis on the translational offset distance d. Numerical computations are considered for a zeroth-order quasi-Gaussian beam chosen as an example to illustrate the analysis. Acoustic resonance scattering directivity diagrams are calculated by subtracting an appropriate background from the expression of the scattered pressure field. In addition, computations for the radiation force exerted on an elastic cylinder centered on the axis of wave propagation of the beam, and shifted off-axially are analyzed and discussed.

  5. Resonance scattering and radiation force calculations for an elastic cylinder using the translational addition theorem for cylindrical wave functions

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.

    2015-09-01

    The standard Resonance Scattering Theory (RST) of plane waves is extended for the case of any two-dimensional (2D) arbitrarily-shaped monochromatic beam incident upon an elastic cylinder with arbitrary location using an exact methodology based on Graf's translational addition theorem for the cylindrical wave functions. The analysis is exact as it does not require numerical integration procedures. The formulation is valid for any cylinder of finite size and material that is immersed in a nonviscous fluid. Partial-wave series expansions (PWSEs) for the incident, internal and scattered linear pressure fields are derived, and the analysis is further extended to obtain generalized expressions for the on-axis and off-axis acoustic radiation force components. The wave-fields are expressed using generalized PWSEs involving the beam-shape coefficients (BSCs) and the scattering coefficients of the cylinder. The off-axial BSCs are expressed analytically in terms of an infinite PWSE with emphasis on the translational offset distance d. Numerical computations are considered for a zeroth-order quasi-Gaussian beam chosen as an example to illustrate the analysis. Acoustic resonance scattering directivity diagrams are calculated by subtracting an appropriate background from the expression of the scattered pressure field. In addition, computations for the radiation force exerted on an elastic cylinder centered on the axis of wave propagation of the beam, and shifted off-axially are analyzed and discussed.

  6. The Effect of Detonation Wave Incidence Angle on the Acceleration of Flyers by Explosives Heavily Laden with Inert Additives

    NASA Astrophysics Data System (ADS)

    Loiseau, Jason; Georges, William; Frost, David; Higgins, Andrew

    2015-06-01

    The incidence angle of a detonation wave is often assumed to weakly influence the terminal velocity of an explosively driven flyer. For explosives heavily loaded with dense additives, this may not be true due to differences in momentum and energy transfer between detonation products, additive particles, and the flyer. For tangential incidence the particles are first accelerated against the flyer via an expansion fan, whereas they are first accelerated by the detonation wave in the normal case. In the current study we evaluate the effect of normal versus tangential incidence on the acceleration of flyers by nitromethane heavily loaded with a variety of additives. Normal detonation was initiated via an explosively driven slapper. Flyer acceleration was measured with heterodyne laser interferometry (PDV). The influence of wave angle is evaluated by comparing the terminal velocity in the two cases (i.e., normal and grazing) for the heavily loaded mixtures. The decrement in flyer velocity correlated primarily with additive volume fraction and had a weak dependence on additive density or particle size. The Gurney energy of the heterogeneous explosive was observed to increase with flyer mass, presumably due to the timescale over which impinging particles could transfer momentum.

  7. Additional Radiative Cooling of the Mesopause Region due to Small-Scale Temperature Fluctuations Associated with Gravity Waves

    NASA Astrophysics Data System (ADS)

    Kutepov, A.; Feofilov, A.; Medvedev, A.; Pauldrach, A.; Hartogh, P.

    2008-05-01

    We address a previously unknown effect of the radiative cooling of the mesosphere and lower thermosphere (MLT) produced by small-scale irregular temperature fluctuations (ITFs) associated with gravity waves. These disturbances are not resolved by present GCMs, but they alter the radiative transfer and the heating/cooling rates significantly. We apply a statistical model of gravity waves superimposed on large-scale temperature profiles, and perform direct calculations of the radiative cooling/heating in the MLT in the IR bands of CO2, O3 and H2O molecules taking into account the breakdown of the local thermodynamic equilibrium (non-LTE). We found that in the periods of strong wave activity the subgrid ITFs can cause an additional cooling up to 3 K/day near the mesopause. The effect is produced mainly by the fundamental 15 μm band of the main CO2 isotope. We derived a simple expression for the correction to mean (resolved by GCMs) temperature profiles using the variance of the temperature perturbations to account for the additional cooling effect. The suggested parameterization can be applied in GCMs in conjunction with existing gravity wave drag parameterizations.

  8. Drift wave stabilized by an additional streaming ion or plasma population.

    PubMed

    Bashir, M F; Vranjes, J

    2015-03-01

    It is shown that the universally unstable kinetic drift wave in an electron-ion plasma can very effectively be suppressed by adding an extra flowing ion (or plasma) population. The effect of the flow of the added ions is essential, their response is of the type (vph-vf0)exp[-(vph-vf0)2], where vf0 is the flow speed and vph is the phase speed parallel to the magnetic field vector. The damping is strong and it is mainly due to this ion exponential term, and this remains so for vf0

  9. Market surveillance on non-halal additives incorporated in surimi based products using polymerase chain reaction (PCR)-southern hybridization analysis

    NASA Astrophysics Data System (ADS)

    Aravindran, S.; Sahilah, A. M.; Aminah, A.

    2014-09-01

    Halal surveillance on halal ingredients incorporated in surimi based products were studied using polymerase chain reaction (PCR)-southern hybridization on chip analysis. The primers used in this technique were targeted on mitochondria DNA (mtDNA) of cytochrome b (cyt b) gene sequence which able to differentiate 7 type (beef, chicken, duck, goat, buffalo, lamb and pork) of species on a single chip. 17 (n = 17*3) different brands of surimi-based product were purchased randomly from Selangor local market in January 2013. Of 17 brands, 3 (n = 3*3) brands were positive for chicken DNA, 1 (n = 1*3) brand was positive for goat DNA, and the remainder 13 brands (n = 13*3) have no DNA species detected. The sensitivity of PCR-southern hybridization primers to detect each meat species was 0.1 ng. In the present study, it is evidence that PCR-Southern Hybridization analysis offered a reliable result due to its highly specific and sensitive properties in detecting non-halal additive such as plasma protein incorporation in surimi-based product.

  10. Enhanced computational prediction of polyethylene wear in hip joints by incorporating cross-shear and contact pressure in additional to load and sliding distance: effect of head diameter.

    PubMed

    Kang, Lu; Galvin, Alison L; Fisher, John; Jin, Zhongmin

    2009-05-11

    A new definition of the experimental wear factor was established and reported as a function of cross-shear motion and contact pressure using a multi-directional pin-on-plate wear testing machine for conventional polyethylene in the present study. An independent computational wear model was developed by incorporating the cross-shear motion and contact pressure-dependent wear factor into the Archard's law, in additional to load and sliding distance. The computational prediction of wear volume was directly compared with a simulator testing of a polyethylene hip joint with a 28 mm diameter. The effect of increasing the femoral head size was subsequently considered and was shown to increase wear, as a result of increased sliding distance and reduced contact pressure. PMID:19261286

  11. Nitrogen and oxygen functionalized hollow carbon materials: The capacitive enhancement by simply incorporating novel redox additives into H2SO4 electrolyte

    NASA Astrophysics Data System (ADS)

    Nie, Yong Fu; Wang, Qian; Chen, Xiang Ying; Zhang, Zhong Jie

    2016-07-01

    In present work, we have developed a simple but effective template carbonization method for producing hollow carbon materials with high content of nitrogen and oxygen from thiocarbanilide. Among all samples, the NPC-1 exhibits high specific surface area (736 m2 g-1) and large pore volume (5.93 cm3 g-1) with high content of heteroatoms (∼11.25 at% nitrogen and ∼5.74 at% oxygen), which is conducive to the improvement of electrochemical performance. Specifically, the high specific capacitance and excellent cycling stability over 5000 cycles of the NPC-1-based electrode are achieved in 1 mol L-1 H2SO4 electrolyte. Additionally, pyrocatechol and rutin as novel redox additives that can easily cause redox-reactions have been incorporated into H2SO4 electrolyte to improve the capacitances. As a result, the NPC-1-R-0.15 and NPC-1-P-0.15 samples deliver high specific capacitances of 120.5 and 368.7 F g-1 at 2 A g-1, respectively, which are much higher than that of the NPC-1 sample (66.2 F g-1) without redox-additives at same current density. Furthermore, the large energy density of 18.9 and 11.9 Wh kg-1 of the NPC-1-based symmetric supercapacitors have been obtained in H2SO4+pyrocatechol and H2SO4+rutin electrolyte, respectively, and both samples also demonstrate excellent cyclic performance for 5000 cycles.

  12. Nitrogen [N]-incorporated ZnO piezoelectric thin films and their application for ultra-small film bulk acoustic wave resonator device fabrication

    SciTech Connect

    Lee, Eunju; Zhang Ruirui; Yoon, Giwan

    2011-10-01

    Nitrogen [N]-incorporated ZnO films with columnar grains of a preferred c-axis orientation were deposited on p-Si (100) wafers, using an RF magnetron sputter deposition technique. For the N incorporation into the ZnO films, an N{sub 2}O gas was used as a doping source and also various process conditions such as N{sub 2}O gas fraction and RF power were applied. Besides, some of the ZnO films were treated with the post annealing process. And then, the micro-structural characteristics of the N-incorporated ZnO films were investigated by a scanning electron microscope, an X-ray diffractometer, and an atomic force microscope techniques. Finally, employing the N-incorporated ZnO films, the solidly mounted resonator-type film bulk acoustic wave resonator devices were fabricated and their resonance characteristics were extracted. As a result, an excellent return loss (S{sub 11}) of- 63 dB was observed at{approx} 0.6 GHz, better than ever reported.

  13. Additive Effects of Millimeter Waves and 2-Deoxyglucose Co-Exposure on the Human Keratinocyte Transcriptome

    PubMed Central

    Soubere Mahamoud, Yonis; Aite, Meziane; Martin, Catherine; Zhadobov, Maxim; Sauleau, Ronan; Le Dréan, Yves

    2016-01-01

    Millimeter Waves (MMW) will be used in the next-generation of high-speed wireless technologies, especially in future Ultra-Broadband small cells in 5G cellular networks. Therefore, their biocompatibilities must be evaluated prior to their massive deployment. Using a microarray-based approach, we analyzed modifications to the whole genome of a human keratinocyte model that was exposed at 60.4 GHz-MMW at an incident power density (IPD) of 20 mW/cm2 for 3 hours in athermic conditions. No keratinocyte transcriptome modifications were observed. We tested the effects of MMWs on cell metabolism by co-treating MMW-exposed cells with a glycolysis inhibitor, 2-deoxyglucose (2dG, 20 mM for 3 hours), and whole genome expression was evaluated along with the ATP content. We found that the 2dG treatment decreased the cellular ATP content and induced a high modification in the transcriptome (632 coding genes). The affected genes were associated with transcriptional repression, cellular communication and endoplasmic reticulum homeostasis. The MMW/2dG co-treatment did not alter the keratinocyte ATP content, but it did slightly alter the transcriptome, which reflected the capacity of MMW to interfere with the bioenergetic stress response. The RT-PCR-based validation confirmed 6 MMW-sensitive genes (SOCS3, SPRY2, TRIB1, FAM46A, CSRNP1 and PPP1R15A) during the 2dG treatment. These 6 genes encoded transcription factors or inhibitors of cytokine pathways, which raised questions regarding the potential impact of long-term or chronic MMW exposure on metabolically stressed cells. PMID:27529420

  14. Additive Effects of Millimeter Waves and 2-Deoxyglucose Co-Exposure on the Human Keratinocyte Transcriptome.

    PubMed

    Soubere Mahamoud, Yonis; Aite, Meziane; Martin, Catherine; Zhadobov, Maxim; Sauleau, Ronan; Le Dréan, Yves; Habauzit, Denis

    2016-01-01

    Millimeter Waves (MMW) will be used in the next-generation of high-speed wireless technologies, especially in future Ultra-Broadband small cells in 5G cellular networks. Therefore, their biocompatibilities must be evaluated prior to their massive deployment. Using a microarray-based approach, we analyzed modifications to the whole genome of a human keratinocyte model that was exposed at 60.4 GHz-MMW at an incident power density (IPD) of 20 mW/cm2 for 3 hours in athermic conditions. No keratinocyte transcriptome modifications were observed. We tested the effects of MMWs on cell metabolism by co-treating MMW-exposed cells with a glycolysis inhibitor, 2-deoxyglucose (2dG, 20 mM for 3 hours), and whole genome expression was evaluated along with the ATP content. We found that the 2dG treatment decreased the cellular ATP content and induced a high modification in the transcriptome (632 coding genes). The affected genes were associated with transcriptional repression, cellular communication and endoplasmic reticulum homeostasis. The MMW/2dG co-treatment did not alter the keratinocyte ATP content, but it did slightly alter the transcriptome, which reflected the capacity of MMW to interfere with the bioenergetic stress response. The RT-PCR-based validation confirmed 6 MMW-sensitive genes (SOCS3, SPRY2, TRIB1, FAM46A, CSRNP1 and PPP1R15A) during the 2dG treatment. These 6 genes encoded transcription factors or inhibitors of cytokine pathways, which raised questions regarding the potential impact of long-term or chronic MMW exposure on metabolically stressed cells.

  15. Additive Effects of Millimeter Waves and 2-Deoxyglucose Co-Exposure on the Human Keratinocyte Transcriptome.

    PubMed

    Soubere Mahamoud, Yonis; Aite, Meziane; Martin, Catherine; Zhadobov, Maxim; Sauleau, Ronan; Le Dréan, Yves; Habauzit, Denis

    2016-01-01

    Millimeter Waves (MMW) will be used in the next-generation of high-speed wireless technologies, especially in future Ultra-Broadband small cells in 5G cellular networks. Therefore, their biocompatibilities must be evaluated prior to their massive deployment. Using a microarray-based approach, we analyzed modifications to the whole genome of a human keratinocyte model that was exposed at 60.4 GHz-MMW at an incident power density (IPD) of 20 mW/cm2 for 3 hours in athermic conditions. No keratinocyte transcriptome modifications were observed. We tested the effects of MMWs on cell metabolism by co-treating MMW-exposed cells with a glycolysis inhibitor, 2-deoxyglucose (2dG, 20 mM for 3 hours), and whole genome expression was evaluated along with the ATP content. We found that the 2dG treatment decreased the cellular ATP content and induced a high modification in the transcriptome (632 coding genes). The affected genes were associated with transcriptional repression, cellular communication and endoplasmic reticulum homeostasis. The MMW/2dG co-treatment did not alter the keratinocyte ATP content, but it did slightly alter the transcriptome, which reflected the capacity of MMW to interfere with the bioenergetic stress response. The RT-PCR-based validation confirmed 6 MMW-sensitive genes (SOCS3, SPRY2, TRIB1, FAM46A, CSRNP1 and PPP1R15A) during the 2dG treatment. These 6 genes encoded transcription factors or inhibitors of cytokine pathways, which raised questions regarding the potential impact of long-term or chronic MMW exposure on metabolically stressed cells. PMID:27529420

  16. Traveling-wave laser-produced-plasma energy source for photoionization laser pumping and lasers incorporating said

    DOEpatents

    Sher, Mark H.; Macklin, John J.; Harris, Stephen E.

    1989-09-26

    A traveling-wave, laser-produced-plasma, energy source used to obtain single-pass gain saturation of a photoionization pumped laser. A cylindrical lens is used to focus a pump laser beam to a long line on a target. Grooves are cut in the target to present a surface near normal to the incident beam and to reduce the area, and hence increase the intensity and efficiency, of plasma formation.

  17. Fast acoustic streaming in standing waves: generation of an additional outer streaming cell.

    PubMed

    Reyt, Ida; Daru, Virginie; Bailliet, Hélène; Moreau, Solène; Valière, Jean-Christophe; Baltean-Carlès, Diana; Weisman, Catherine

    2013-09-01

    Rayleigh streaming in a cylindrical acoustic standing waveguide is studied both experimentally and numerically for nonlinear Reynolds numbers from 1 to 30 [Re(NL)=(U0/c0)(2)(R/δν)(2), with U0 the acoustic velocity amplitude at the velocity antinode, c0 the speed of sound, R the tube radius, and δν the acoustic boundary layer thickness]. Streaming velocity is measured by means of laser Doppler velocimetry in a cylindrical resonator filled with air at atmospheric pressure at high intensity sound levels. The compressible Navier-Stokes equations are solved numerically with high resolution finite difference schemes. The resonator is excited by shaking it along the axis at imposed frequency. Results of measurements and of numerical calculation are compared with results given in the literature and with each other. As expected, the axial streaming velocity measured and calculated agrees reasonably well with the slow streaming theory for small ReNL but deviates significantly from such predictions for fast streaming (ReNL>1). Both experimental and numerical results show that when ReNL is increased, the center of the outer streaming cells are pushed toward the acoustic velocity nodes until counter-rotating additional vortices are generated near the acoustic velocity antinodes.

  18. Demonstration of the Recent Additions in Modeling Capabilities for the WEC-Sim Wave Energy Converter Design Tool: Preprint

    SciTech Connect

    Tom, N.; Lawson, M.; Yu, Y. H.

    2015-03-01

    WEC-Sim is a mid-fidelity numerical tool for modeling wave energy conversion (WEC) devices. The code uses the MATLAB SimMechanics package to solve the multi-body dynamics and models the wave interactions using hydrodynamic coefficients derived from frequency domain boundary element methods. In this paper, the new modeling features introduced in the latest release of WEC-Sim will be presented. The first feature discussed is the conversion of the fluid memory kernel to a state-space approximation that provides significant gains in computational speed. The benefit of the state-space calculation becomes even greater after the hydrodynamic body-to-body coefficients are introduced as the number of interactions increases exponentially with the number of floating bodies. The final feature discussed is the capability toadd Morison elements to provide additional hydrodynamic damping and inertia. This is generally used as a tuning feature, because performance is highly dependent on the chosen coefficients. In this paper, a review of the hydrodynamic theory for each of the features is provided and successful implementation is verified using test cases.

  19. Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998-2000 tropical ozone climatology 2. Tropospheric variability and the zonal wave-one

    NASA Astrophysics Data System (ADS)

    Thompson, Anne M.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Schmidlin, Francis J.; Logan, Jennifer A.; Fujiwara, Masatomo; Kirchhoff, Volker W. J. H.; Posny, FrançOise; Coetzee, Gert J. R.; Hoegger, Bruno; Kawakami, Shuji; Ogawa, Toshihiro; Fortuin, J. P. F.; Kelder, H. M.

    2003-01-01

    The first view of stratospheric and tropospheric ozone variability in the Southern Hemisphere tropics is provided by a 3-year record of ozone soundings from the Southern Hemisphere Additional Ozonesondes (SHADOZ) network (http://croc.gsfc.nasa.gov/shadoz). Observations covering 1998-2000 were made over Ascension Island, Nairobi (Kenya), Irene (South Africa), Réunion Island, Watukosek (Java), Fiji, Tahiti, American Samoa, San Cristóbal (Galapagos), and Natal (Brazil). Total, stratospheric, and tropospheric column ozone amounts usually peak between August and November. Other features are a persistent zonal wave-one pattern in total column ozone and signatures of the quasi-biennial oscillation (QBO) in stratospheric ozone. The wave-one is due to a greater concentration of free tropospheric ozone over the tropical Atlantic than the Pacific and appears to be associated with tropical general circulation and seasonal pollution from biomass burning. Tropospheric ozone over the Indian and Pacific Oceans displays influences of the waning 1997-1998 El Niño, seasonal convection, and pollution transport from Africa. The most distinctive feature of SHADOZ tropospheric ozone is variability in the data, e.g., a factor of 3 in column amount at 8 of 10 stations. Seasonal and monthly means may not be robust quantities because statistics are frequently not Gaussian even at sites that are always in tropical air. Models and satellite retrievals should be evaluated on their capability for reproducing tropospheric variability and fine structure. A 1999-2000 ozone record from Paramaribo, Surinam (6°N, 55°W) (also in SHADOZ) shows a marked contrast to southern tropical ozone because Surinam is often north of the Intertropical Convergence Zone (ITCZ). A more representative tropospheric ozone climatology for models and satellite retrievals requires additional Northern Hemisphere tropical data.

  20. Thermal formation of PBDD/F from tetrabromobisphenol A--a comparison of polymer linked TBBP A with its additive incorporation in thermoplastics.

    PubMed

    Wichmann, H; Dettmer, F T; Bahadir, M

    2002-04-01

    For a long period, polybrominated flame retardants are under discussion because of the formation of polybrominated dibenzo-p-dioxins (PBDD)/dibenzofurans (PBDF) (PBDD/F) in case of thermal stress. Concerning polymer linked tetrabromobisphenol A (TBBP A), formation of PBDD/F was commonly presumed to be sterically hindered because of the covalent fixation into the polymer backbone. Combustion experiments with additively incorporated TBBP A compared with its polymer linkage revealed, that this assumption is incorrect and has to be revised. Under same conditions, similar PBDD/F concentrations in the range of 17.5-19.6 mg PBBD/F per kg TBBP A applied were analyzed. PBDD/F homologue distribution patterns were almost identical predominated by low brominated PBDF. These findings for PBDD/F formation have to be considered in future discussions regarding thermal stress caused by combustion or recycling processes, including other flame retardants bound in polymer matrix, e.g. polybrominated polystyrene (PS), or those with molecular structures showing less analogy to PBDD/F, like hexabromocyclododecane. The second aspect introduced, is the influence of different plastics on the formation rates of PBDD/F. In this context, combustion experiments were performed in an atmosphere consisting of synthetic air and HBr. PBDD/F concentrations were 8.47 mg/kg polyethylene, 1.67 mg/kg PS, 3.92 mg/kg phenolic resin and 18.1 mg/kg epoxy resin. Distribution patterns of PBDD/F homologues could partly be correlated with the occurrence of the precursors polybrominated benzenes and phenols.

  1. Mn incorporation in as-grown and annealed (Ga,Mn)As layers studied by x-ray diffraction and standing-wave fluorescence

    SciTech Connect

    Holy, V.; Matej, Z.; Pacherova, O.; Novak, V.; Cukr, M.; Olejnik, K.; Jungwirth, T.

    2006-12-15

    A combination of high-resolution x-ray diffraction and a technique of x-ray standing-wave fluorescence at grazing incidence is employed to study the structure of a (Ga,Mn)As-diluted magnetic semiconductor and its changes during post-growth annealing steps. We find that the film is formed by a uniform, single-crystallographic phase epilayer covered by a thin surface layer with enhanced Mn concentration to Mn atoms at random noncrystallographic positions. In the epilayer, Mn incorporated at the interstitial position has a dominant effect on lattice expansion as compared to substitutional Mn. The expansion coefficient of interstitial Mn estimated from our data is consistent with theory predictions. The concentration of interstitial Mn and the corresponding lattice expansion of the epilayer are reduced by annealing, accompanied by an increase of the density of randomly distributed Mn atoms in the disordered surface layer. Substitutional Mn atoms remain stable during the low-temperature annealing.

  2. Identifying Coronary Artery Disease in Asymptomatic Middle-Aged Sportsmen: The Additional Value of Pulse Wave Velocity

    PubMed Central

    Braber, Thijs L.; Prakken, Niek H. J.; Mosterd, Arend; Mali, Willem P. Th. M.; Doevendans, Pieter A. F. M.; Bots, Michiel L.; Velthuis, Birgitta K.

    2015-01-01

    Background Cardiovascular screening may benefit middle-aged sportsmen, as coronary artery disease (CAD) is the main cause of exercise-related sudden cardiac death. Arterial stiffness, as measured by pulse wave velocity (PWV), may help identify sportsmen with subclinical CAD. We examined the additional value of PWV measurements to traditional CAD risk factors for identifying CAD. Methods From the Measuring Athlete’s Risk of Cardiovascular events (MARC) cohort of asymptomatic, middle-aged sportsmen who underwent low-dose Cardiac CT (CCT) after routine sports medical examination (SME), 193 consecutive sportsmen (aged 55±6.6 years) were included with additional PWV measurements before CCT. Sensitivity, specificity and predictive values of PWV values (>8.3 and >7.5m/s) assessed by Arteriograph were used to identify CAD (coronary artery calcium scoring ≥100 Agatston Units or coronary CT angiography luminal stenosis ≥50%) and to assess the additional diagnostic value of PWV to established cardiovascular risk factors. Results Forty-seven sportsmen (24%) had CAD on CCT. They were older (58.9 vs. 53.8 years, p<0.001), had more hypertension (17 vs. 4%, p=0.003), higher cholesterol levels (5.7 vs. 5.4mmol/l) p=0.048), and more often were (ever) smokers (55 vs. 34%, p=0.008). Mean PWV was higher in those with CAD (8.9 vs. 8.0 m/s, p=0.017). For PWV >8.3m/s respectively >7.5m/s sensitivity to detect CAD on CT was 43% and 74%, specificity 69% and 45%, positive predictive value 31% and 30%, and negative predictive value 79% and 84%. Adding PWV to traditional risk factor models did not change the area under the curve (from 0.78 (95% CI = 0.709-0.848)) to AUC 0.78 (95% CI 0.710-0.848, p = 0.99)) for prediction of CAD on CCT. Conclusions Limited additional value was found for PWV on top of established risk factors to identify CAD. PWV might still have a role to identify CAD in middle-aged sportsmen if risk factors such as cholesterol are unknown. PMID:26147752

  3. A square-wave adsorptive stripping voltammetric method for the determination of Amaranth, a food additive dye.

    PubMed

    Alghamdi, Ahmad H

    2005-01-01

    Square-wave adsorptive stripping voltammetric (AdSV) determinations of trace concentrations of the azo coloring agent Amaranth are described. The analytical methodology used was based on the adsorptive preconcentration of the dye on the hanging mercury drop electrode, followed by initiation of a negative sweep. In a pH 10 carbonate supporting electrolyte, Amaranth gave a well-defined and sensitive AdSV peak at -518 mV. The electroanalytical determination of this azo dye was found to be optimal in carbonate buffer (pH 10) under the following experimental conditions: accumulation time, 120 s; accumulation potential, 0.0 V; scan rate, 600 mV/s; pulse amplitude, 90 mV; and frequency, 50 Hz. Under these optimized conditions the AdSV peak current was proportional over the concentration range 1 x 10(-8)-1.1 x 10(-7) mol/L (r = 0.999) with a detection limit of 1.7 x 10(-9) mol/L (1.03 ppb). This analytical approach possessed enhanced sensitivity, compared with conventional liquid chromatography or spectrophotometry and it was simple and fast. The precision of the method, expressed as the relative standard deviation, was 0.23%, whereas the accuracy, expressed as the mean recovery, was 104%. Possible interferences by several substances usually present as food additive azo dyes (E110, E102), gelatin, natural and artificial sweeteners, preservatives, and antioxidants were also investigated. The developed electroanalyticals method was applied to the determination of Amaranth in soft drink samples, and the results were compared with those obtained by a reference spectrophotometric method. Statistical analysis (paired t-test) of these data showed that the results of the 2 methods compared favorably.

  4. Influence of incorporated bromodeoxyuridine on the induction of chromosomal alterations by ionizing radiation and long-wave UV in CHO cells.

    PubMed

    Zwanenburg, T S; van Zeeland, A A; Natarajan, A T

    1985-01-01

    Incorporation of BrdUrd into nuclear DNA sensitizes CHO cells (1) to the induction of chromosomal aberrations by X-rays and 0.5 MeV neutrons and (2) to induction of chromosomal aberrations and SCEs by lw-UV. We have attempted to establish a correlation between induced chromosomal alterations and induced single- or double-strand breaks in DNA. The data show that while DSBs correlate very well with X-ray-induced aberrations, no clear correlation could be established between lw-UV induced SSBs (including alkali-labile sites) and chromosomal alterations. In addition the effect of 3-aminobenzamide (3AB) on the induction of chromosomal aberrations and SCEs induced by lw-UV has been determined. It is shown that 3AB is without any effect when lw-UV-irradiated cells are posttreated with this inhibitor. The significance of these results is discussed.

  5. Gravity and Rossby wave signatures in the tropical troposphere and lower stratosphere based on Southern Hemisphere Additional Ozonesondes (SHADOZ), 1998-2007

    NASA Astrophysics Data System (ADS)

    Thompson, Anne M.; Allen, Amber L.; Lee, Sukyoung; Miller, Sonya K.; Witte, Jacquelyn C.

    2011-03-01

    Prior investigations attempted to determine the relative influence of advection and convective processes on ozone and water vapor distributions in the tropical tropopause layer (TTL) through analyses of tracers, related physical parameters (e.g., outgoing long-wave radiation, precipitable water, and temperature), or with models. In this study, stable laminae in Southern Hemisphere Additional Ozonesonde Network (SHADOZ) ozone profiles from 1998 to 2007 are interpreted in terms of gravity waves (GW) or Rossby waves (RW) that are identified with vertical and quasi-horizontal displacements, respectively. Using the method of Pierce and Grant (1998) as applied by Thompson et al. (2007a, 2007b, 2010, 2011), amplitudes and frequencies in ozone laminae are compared among representative SHADOZ sites over Africa and the Pacific, Indian, and Atlantic oceans. GW signals maximize in the TTL and lower stratosphere. Depending on site and season, GW are identified in up to 90% of the soundings. GW are most prevalent over the Pacific and eastern Indian oceans, a distribution consistent with vertically propagating equatorial Kelvin waves. Ozone laminae from RW occur more often below the tropical tropopause and with lower frequency (<20%). Gravity wave and Rossby wave indices (GWI, RWI) are formulated to facilitate analysis of interannual variability of wave signatures among sites. GWI is positively correlated with a standard ENSO (El Niño-Southern Oscillation) index over American Samoa (14°S, 171°W) and negatively correlated at Watukosek, Java (7.5°S, 114°E), Kuala Lumpur (3°N, 102°E), and Ascension Island (8°S, 15°W). Generally, the responses of GW and RW to ENSO are consistent with prior studies.

  6. Gravity and Rossby Wave Signatures in the Tropical Troposphere and Lower Stratosphere Based on Southern Hemisphere Additional Ozonesondes (SHADOZ), 1998-2007

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Allen, Amber L.; Lee, Sukyoung; Miller, Sonya K.; Witte, Jacquelyn C.

    2011-01-01

    Prior investigations attempted to determine the relative influence of advection and convective processes on ozone and water vapor distributions in the tropical tropopause layer (TTL) through analyses of tracers, related physical parameters (e.g., outgoing long-wave radiation, precipitable water, and temperature), or with models. In this study, stable laminae in Southern Hemisphere Additional Ozonesonde Network (SHADOZ) ozone profIles from 1998 to 2007 are interpreted in terms of gravity waves (GW) or Rossby waves (RW) that are identified with vertical and quasi-horizontal displacements, respectively. Using the method of Pierce and Grant (1998) as applied by Thompson et al. (2007a, 2007b, 2010, 2011), amplitudes and frequencies in ozone laminae are compared among representative SHADOZ sites over Africa and the Pacific, Indian, and Atlantic oceans. GW signals maximize in the TTL and lower stratosphere. Depending on site and season, GW are identified in up to 90% of the soundings. GW are most prevalent over the Pacific and eastern Indian oceans, a distribution consistent with vertically propagating equatorial Kelvin waves. Ozone laminae from RW occur more often below the tropical tropopause and with lower frequency 20%). Gravity wave and Rossby wave indices (GWI, RWI) are formulated to facilitate analysis of interannual variability of wave signatures among sites. GWI is positively correlated with a standard ENSO (El Nino-Southern Oscillation) index over American Samoa (14degS, 171degW) and negatively correlated at Watukosek, Java (7.5degS, 114degE), Kuala Lumpur (3degN, 102degE), and Ascension Island (80degS, 15degW). Generally, the responses of GW and RW to ENSO are consistent with prior studies.

  7. Incorporation of {sup 210}Pb and {sup 210}Po to Poultry through the Addition of Dicalcium Phosphate (DCP) to the Diet

    SciTech Connect

    Casacuberta, N.; Masque, P.; Garcia-Orellana, J.; Gasa, J.; Anguita, M.

    2008-08-07

    Due to the replacement of calcium by uranium in the phosphorite, sedimentary phosphate rock contains high concentrations of {sup 238}U (i.e. from 1500 Bq{center_dot}kg{sup -1} in Morocco to 4000 Bq{center_dot}kg{sup -1} in Tanzania ores). Dicalcium Phosphate (DCP) is produced by the wet acid digestion of the phosphorite, and is used as a source of calcium and phosphorus for livestock feed supplement. If the phosphorite acid digestion is made with hydrochloric acid, DCP may present specific activities of about 10{sup 3} Bq{center_dot}kg{sup -1} of {sup 238}U and some of its decay chain daughters. In particular, due to its radiological implications, the presence of {sup 210}Pb and {sup 210}Po in DCP is of special relevance. The aim of this work was to investigate the potential incorporation of these radionuclides to poultry through its diet. Three different diets were therefore prepared with different contents of both DCP and {sup 210}Pb and {sup 210}Po. Diet A was used as a blank, and had a 2.5% in weight of monocalcium phosphate (MCP); diet B, with a 5% in weight of DCP; and diet C, with a 2.5% of DCP. Concentrations of {sup 210}Pb were 0.93, 101.4 and 51.2 Bq{center_dot}kg{sup -1}; whereas concentrations of {sup 210}Po were 0.92, 74 and 36 Bq{center_dot}kg{sup -1} of food for diets A, B and C, respectively. Accumulation of {sup 210}Pb and {sup 210}Po was analysed at several times during poultry growth in samples of bone, liver, kidney, muscle, excrements as well as entire animals, with a total of 30 broilers fed with the 3 different diets. Results showed clear enhancements in the accumulation of both {sup 210}Pb and {sup 210}Po in chicken for diets B and C, and in particular in liver and bone. However, total accumulation of radionuclides in chicken, and especially in edible parts, is low compared to its expulsion through excrements. These results are interpreted in terms of the potential dose through consumption of chicken.

  8. Aluminum bioavailability from the approved food additive leavening agent acidic sodium aluminum phosphate, incorporated into a baked good, is lower than from water.

    PubMed

    Yokel, Robert A; Florence, Rebecca L

    2006-10-01

    There are estimates of oral aluminum (Al) bioavailability from drinking water, but little information on Al bioavailability from foods. Foods contribute approximately 95% and drinking water 1-2% of the typical human's daily Al intake. The objectives were to estimate oral Al bioavailability from a representative food containing the food additive acidic sodium aluminum phosphate (acidic SALP), a leavening agent in baked goods. Rats were acclimated to a special diet that resulted in no stomach contents 14 h after its withdrawal. They were trained to rapidly consume a biscuit containing 1.5% acidic SALP. Oral Al bioavailability was then determined from a biscuit containing 1% or 2% acidic SALP, synthesized to contain (26)Al. The rats received concurrent (27)Al infusion. Blood was repeatedly withdrawn and serum analyzed for (26)Al by accelerator mass spectrometry. Total Al was determined by atomic absorption spectrometry. Oral (26)Al bioavailability was determined from the area under the (26)Al, compared to (27)Al, serum concentrationxtime curves. Oral Al bioavailability (F) from biscuit containing 1% or 2% acidic (26)Al-SALP averaged approximately 0.11% and 0.13%; significantly less than from water, which was previously shown to be approximately 0.3%. The time to maximum serum (26)Al concentration was 4.2 and 6h after consumption of biscuit containing 1% or 2% (26)Al-acidic SALP, respectively, compared to 1-2h following (26)Al in water. These results of oral Al bioavailability from acidic (26)Al-SALP in a biscuit (F approximately 0.1%) and results from (26)Al in water (F approximately 0.3%) x the contributions of food and drinking water to the typical human's daily Al intake ( approximately 5-10mg from food and 0.1mg from water, respectively) suggest food provides approximately 25-fold more Al to systemic circulation, and potential Al body burden, than does drinking water.

  9. Velocity structure of the NE Tibetan Plateau: P and S body wave tomographic model of the northeastern Tibetan Plateau and its margins with additional constraints from surface wave tomography

    NASA Astrophysics Data System (ADS)

    Nunn, C.; Roecker, S. W.; Tilmann, F. J.; Priestley, K. F.; Heyburn, R.; Mechie, J.; Sandvol, E. A.; Ni, J. F.; Chen, Y. J.; Zhao, W.

    2012-12-01

    The northeastern margin of the Tibetan plateau, which includes the Qiangtang and Songpan-Ganzi terranes as well as the Kunlun Shan and part of the Qaidam basin, continues to uplift and deform in response to the ongoing India-Eurasia collision. To test competing hypotheses concerning the mechanisms for this deformation, we assembled a high quality data set of more than 19,000 P- and 3,500 S-wave arrival times from earthquakes at teleseismic distances from the INDEPTH-IV and ASCENT broadband seismometer deployments. We analyze these arrival times to construct tomographic images of P- and S-wave velocities in the crust and upper mantle beneath this part of the plateau. Starting models for these inversions are generated from a combination of results from recent surface wave investigations and Moho depth maps from receiver function studies. We find that our results are largely insensitive to the choice of starting model, especially at depths greater than 125 km. Nevertheless, the incorporation of surface wave models considerably aids our interpretation of the body wave based images. Resolution tests indicate that features of 150 km length scale are reliably imaged throughout the study region, and at smaller scale in areas of good coverage, but with significant smearing in the vertical direction. Our results suggest that, south of the Qaidam basin, the underthrusting Indian plate is sub-horizontal, at least 100 km thick, and below depths of ~140km. The lower part of the Indian plate is likely to reach as far north as ~34.5°, which corresponds to the Jinsha Suture in the west and the South Kunlun Fault in the east. A structure previously thought to be down-welling Indian lithosphere is resolved in our images into two separate fast wavespeed anomalies. We see no evidence of southward-directed subduction of the Qaidam basin under the Tibetan plateau. Our models corroborate results of previous work which imaged a relatively slow wavespeed region between the basin and the

  10. INCORPORATING KINETIC PHYSICS INTO A TWO-FLUID SOLAR-WIND MODEL WITH TEMPERATURE ANISOTROPY AND LOW-FREQUENCY ALFVEN-WAVE TURBULENCE

    SciTech Connect

    Chandran, Benjamin D. G.; Dennis, Timothy J.; Quataert, Eliot; Bale, Stuart D. E-mail: tim.dennis@unh.edu E-mail: bale@ssl.berkeley.edu

    2011-12-20

    We develop a one-dimensional solar-wind model that includes separate energy equations for the electrons and protons, proton temperature anisotropy, collisional and collisionless heat flux, and an analytical treatment of low-frequency, reflection-driven, Alfven-wave (AW) turbulence. To partition the turbulent heating between electron heating, parallel proton heating, and perpendicular proton heating, we employ results from the theories of linear wave damping and nonlinear stochastic heating. We account for mirror and oblique firehose instabilities by increasing the proton pitch-angle scattering rate when the proton temperature anisotropy exceeds the threshold for either instability. We numerically integrate the equations of the model forward in time until a steady state is reached, focusing on two fast-solar-wind-like solutions. These solutions are consistent with a number of observations, supporting the idea that AW turbulence plays an important role in the origin of the solar wind.

  11. The 1998-2000 SHADOZ (Southern Hemisphere ADditional OZonesondes) Tropical Ozone Climatology. 2; Stratospheric and Tropospheric Ozone Variability and the Zonal Wave-One

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Schmidlin, Francis J.; Logan, Jennifer A.; Fujiwara, Masatomo; Kirchhoff, Volker W. J. H.; Posny, Francoise; Coetzee, Gert J. R.; Hoegger, Bruno; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    This is the second 'reference' or 'archival' paper for the SHADOZ (Southern Hemisphere Additional Ozonesondes) network and is a follow-on to the recently accepted paper with similar first part of title. The latter paper compared SHADOZ total ozone with satellite and ground-based instruments and showed that the equatorial wave-one in total ozone is in the troposphere. The current paper presents details of the wave-one structure and the first overview of tropospheric ozone variability over the southern Atlantic, Pacific and Indian Ocean basins. The principal new result is that signals of climate effects, convection and offsets between biomass burning seasonality and tropospheric ozone maxima suggest that dynamical factors are perhaps more important than pollution in determining the tropical distribution of tropospheric ozone. The SHADOZ data at () are setting records in website visits and are the first time that the zonal view of tropical ozone structure has been recorded - thanks to the distribution of the 10 sites that make up this validation network.

  12. Research of the Additional Losses Occurring in Optical Fiber at its Multiple Bends in the Range Waves 1310nm, 1550nm and 1625nm Long

    NASA Astrophysics Data System (ADS)

    Yurchenko, A. V.; Gorlov, N. I.; Alkina, A. D.; Mekhtiev, A. D.; Kovtun, A. A.

    2016-01-01

    Article is devoted to research of the additional losses occurring in the optical fiber at its multiple bends in the range waves of 1310 nanometers, 1550 nanometers and 1625 nanometers long. Article is directed on creation of the external factors methods which allow to estimate and eliminate negative influence. The automated way of calculation of losses at a bend is developed. Results of scientific researches are used by engineers of “Kazaktelekom” AS for practical definition of losses service conditions. For modeling the Wolfram|Alpha environment — the knowledge base and a set of computing algorithms was chosen. The greatest losses are noted on wavelength 1310nm and 1625nm. All dependences are nonlinear. Losses with each following excess are multiplicative.

  13. A study protocol of a randomised controlled trial incorporating a health economic analysis to investigate if additional allied health services for rehabilitation reduce length of stay without compromising patient outcomes

    PubMed Central

    2010-01-01

    controlled trial. Discussion This paper outlines the study protocol for the first fully powered randomised controlled trial incorporating a health economic analysis to establish if additional Saturday allied health services for rehabilitation inpatients reduces length of stay without compromising discharge outcomes. If successful, this trial will have substantial health benefits for the patients and for organizations delivering rehabilitation services. Clinical trial registration number Australian and New Zealand Clinical Trials Registry ACTRN12609000973213 PMID:21073703

  14. Signal-to-noise ratio in direct-detection mid-infrared Random-Modulation Continuous-Wave lidar in the presence of colored additive noise.

    PubMed

    Rybaltowski, A; Taflove, A

    2001-10-01

    We have derived the signal-to-noise ratio in direct-detection Random-Modulation Continuous-Wave (RM-CW) lidar in the presence of colored additive noise. In contrast to a known formula derived for the photon shot-noise regime, which may adequately describe experimental conditions in the near-infrared, our result is applicable mainly at longer, mid-infrared wavelengths. Unlike the former formula, our result is explicitly dependent on the pseudorandom code (PRC) used for modulation. Three known modulation codes, the M-, A1-, and A2-sequence are compared and shown to have practically equivalent signal and noise properties (provided that clutter inherent in the A1- and A2-sequence is neglected), except that the M-sequence has a near-zero-frequency noise pickup that degrades its performance in real measurement systems. This difference provides an alternative explanation of a better performance of the A1-/A2-sequence in a previous experiment [3], carried out in the near-infrared. It suggests the presence of an additive noise component and thus some applicability of our result also in near-infrared lidar. A need for balanced sequences - particularly in the mid-infrared - is explained, although in a different way than previously suggested in near-infrared, photon shot noise-limited lidar. Additional, sinusoidal carrier modulation is considered and shown to have significant drawbacks. Our results allow comparison of given modulation sequences, and construction of improved ones. Interestingly, the improved sequences will possess less "random" characteristics, seemingly against the underlying concept of random modulation.

  15. On the physics of waves in the solar atmosphere: Wave heating and wind acceleration

    NASA Technical Reports Server (NTRS)

    Musielak, Z. E.

    1994-01-01

    This paper presents work performed on the generation and physics of acoustic waves in the solar atmosphere. The investigators have incorporated spatial and temporal turbulent energy spectra in a newly corrected version of the Lighthill-Stein theory of acoustic wave generation in order to calculate the acoustic wave energy fluxes generated in the solar convective zone. The investigators have also revised and improved the treatment of the generation of magnetic flux tube waves, which can carry energy along the tubes far away from the region of their origin, and have calculated the tube wave energy fluxes for the sun. They also examine the transfer of the wave energy originated in the solar convective zone to the outer atmospheric layers through computation of wave propagation and dissipation in highly nonhomogeneous solar atmosphere. These waves may efficiently heat the solar atmosphere and the heating will be especially significant in the chromospheric network. It is also shown that the role played by Alfven waves in solar wind acceleration and coronal hole heating is dominant. The second part of the project concerned investigation of wave propagation in highly inhomogeneous stellar atmospheres using an approach based on an analytic tool developed by Musielak, Fontenla, and Moore. In addition, a new technique based on Dirac equations has been developed to investigate coupling between different MHD waves propagating in stratified stellar atmospheres.

  16. Numerical modeling of the effects of wave energy converter characteristics on nearshore wave conditions

    SciTech Connect

    Chang, G.; Ruehl, K.; Jones, C. A.; Roberts, J.; Chartrand, C.

    2015-12-24

    Modeled nearshore wave propagation was investigated downstream of simulated wave energy converters (WECs) to evaluate overall near- and far-field effects of WEC arrays. Model sensitivity to WEC characteristics and WEC array deployment scenarios was evaluated using a modified version of an industry standard wave model, Simulating WAves Nearshore (SWAN), which allows the incorporation of device-specific WEC characteristics to specify obstacle transmission. The sensitivity study illustrated that WEC device type and subsequently its size directly resulted in wave height variations in the lee of the WEC array. Wave heights decreased up to 30% between modeled scenarios with and without WECs for large arrays (100 devices) of relatively sizable devices (26 m in diameter) with peak power generation near to the modeled incident wave height. Other WEC types resulted in less than 15% differences in modeled wave height with and without WECs, with lesser influence for WECs less than 10 m in diameter. Wave directions and periods were largely insensitive to changes in parameters. Furthermore, additional model parameterization and analysis are required to fully explore the model sensitivity of peak wave period and mean wave direction to the varying of the parameters.

  17. Numerical modeling of the effects of wave energy converter characteristics on nearshore wave conditions

    DOE PAGESBeta

    Chang, G.; Ruehl, K.; Jones, C. A.; Roberts, J.; Chartrand, C.

    2015-12-24

    Modeled nearshore wave propagation was investigated downstream of simulated wave energy converters (WECs) to evaluate overall near- and far-field effects of WEC arrays. Model sensitivity to WEC characteristics and WEC array deployment scenarios was evaluated using a modified version of an industry standard wave model, Simulating WAves Nearshore (SWAN), which allows the incorporation of device-specific WEC characteristics to specify obstacle transmission. The sensitivity study illustrated that WEC device type and subsequently its size directly resulted in wave height variations in the lee of the WEC array. Wave heights decreased up to 30% between modeled scenarios with and without WECs formore » large arrays (100 devices) of relatively sizable devices (26 m in diameter) with peak power generation near to the modeled incident wave height. Other WEC types resulted in less than 15% differences in modeled wave height with and without WECs, with lesser influence for WECs less than 10 m in diameter. Wave directions and periods were largely insensitive to changes in parameters. Furthermore, additional model parameterization and analysis are required to fully explore the model sensitivity of peak wave period and mean wave direction to the varying of the parameters.« less

  18. c-axis inclined ZnO films for shear-wave transducers deposited by reactive sputtering using an additional blind

    SciTech Connect

    Link, M.; Schreiter, M.; Weber, J.; Gabl, R.; Pitzer, D.; Primig, R.; Wersing, W.; Assouar, M.B.; Elmazria, O.

    2006-03-15

    This article reports on the growth and characterization of polycrystalline ZnO films having c axis inclined up to 16 deg. with respect to the substrate normal. These films allow the excitation of shear and longitudinal waves with comparable electromechanical coupling constants and are of significant interest for thin film bulk acoustic resonators (FBARs). The films are deposited on silicon substrates covered by Al{sub 2}O{sub 3} and SiO{sub 2} buffer layers under low pressure using a modified reactive dc-pulsed magnetron sputtering system. A blind has been positioned between target and substrate, allowing oblique particle incidence without tilting the wafer. The study of structural properties of the deposited ZnO films by x-ray diffraction and scanning electron microscopy has permitted to show the presence of the inclined structure. Electromechanical coupling constants K up to 13% have been extracted for shear-mode excitation using highly overmoded FBARs.

  19. On the physics of waves in the solar atmosphere: Wave heating and wind acceleration

    NASA Technical Reports Server (NTRS)

    Musielak, Z. E.

    1993-01-01

    This paper presents work performed on the generation and physics of acoustic waves in the solar atmosphere. The investigators have incorporated spatial and temporal turbulent energy spectra in a newly corrected version of the Lighthill-Stein theory of acoustic wave generation in order to calculate the acoustic wave energy fluxes generated in the solar convective zone. The investigators have also revised and improved the treatment of the generation of magnetic flux tube waves, which can carry energy along the tubes far away from the region of their origin, and have calculated the tube energy fluxes for the sun. They also examine the transfer of the wave energy originated in the solar convective zone to the outer atmospheric layers through computation of wave propagation and dissipation in highly nonhomogeneous solar atmosphere. These waves may efficiently heat the solar atmosphere and the heating will be especially significant in the chromospheric network. It is also shown that the role played by Alfven waves in solar wind acceleration and coronal hole heating is dominant. The second part of the project concerned investigation of wave propagation in highly inhomogeneous stellar atmospheres using an approach based on an analytic tool developed by Musielak, Fontenla, and Moore. In addition, a new technique based on Dirac equations has been developed to investigate coupling between different MHD waves propagating in stratified stellar atmospheres.

  20. WindWaveFloat

    SciTech Connect

    Weinstein, Alla

    2011-11-01

    Presentation from the 2011 Water Peer Review includes in which principal investigator Alla Weinstein discusses project progress in development of a floating offshore wind structure - the WindFloat - and incorporation therin of a Spherical Wave Energy Device.

  1. DISTRIBUTED AMPLIFIER INCORPORATING FEEDBACK

    DOEpatents

    Bell, P.R. Jr.

    1958-10-21

    An improved distributed amplifier system employing feedback for stabilization is presented. In accordance with the disclosed invention, a signal to be amplified is applled to one end of a suitable terminated grid transmission line. At intervals along the transmission line, the signal is fed to stable, resistance-capacitance coupled amplifiers incorporating feedback loops therein. The output current from each amplifier is passed through an additional tube to minimize the electrostatic capacitance between the tube elements of the last stage of the amplifier, and fed to appropriate points on an output transmission line, similar to the grid line, but terminated at the opposite (input) end. The output taken from the unterminated end of the plate transmission line is proportional to the input voltage impressed upon the grid line.

  2. Hysteresis of ionization waves

    SciTech Connect

    Dinklage, A.; Bruhn, B.; Testrich, H.; Wilke, C.

    2008-06-15

    A quasi-logistic, nonlinear model for ionization wave modes is introduced. Modes are due to finite size of the discharge and current feedback. The model consists of competing coupled modes and it incorporates spatial wave amplitude saturation. The hysteresis of wave mode transitions under current variation is reproduced. Sidebands are predicted by the model and found in experimental data. The ad hoc model is equivalent to a general--so-called universal--approach from bifurcation theory.

  3. Selenium incorporation using recombinant techniques

    SciTech Connect

    Walden, Helen

    2010-04-01

    An overview of techniques for recombinant incorporation of selenium and subsequent purification and crystallization of the resulting labelled protein. Using selenomethionine to phase macromolecular structures is common practice in structure determination, along with the use of selenocysteine. Selenium is consequently the most commonly used heavy atom for MAD. In addition to the well established recombinant techniques for the incorporation of selenium in prokaryal expression systems, there have been recent advances in selenium labelling in eukaryal expression, which will be discussed. Tips and things to consider for the purification and crystallization of seleno-labelled proteins are also included.

  4. "Directed" assembly of metallacalix[n]arenes with pyrimidine nucleobase ligands of low symmetry: interchanging metals in mixed-metal metallacalix[4]arenes and incorporating additional metals at the exocyclic groups.

    PubMed

    Khutia, Anupam; Sanz Miguel, Pablo J; Lippert, Bernhard

    2011-04-01

    The pyrimidine (pym) nucleobase cytosine (H(2)C) forms cyclic ring structures ("metallacalix[n]arenes") when treated with square-planar cis-a(2)M(II) entities (M=Pt, Pd; a=NH(3) or a(2)=diamine). The number of possible linkage isomers for a given n and the number of possible rotamers can be substantially reduced if a "directed" approach is pursued. Hence, two cytosine ligands are bonded in a defined way to a kinetically robust platinum corner stone. In the accompanying paper (Part I: A. Khutia, P. J. Sanz Miguel, B. Lippert, Chem. Eur. J. 2010, 17, DOI: 10.1002/chem.2010002722) we have demonstrated this principle by allowing cis-[Pta(2)(H(2)C-N3)(2)](2+) to react with (en)Pd(II) to give cycles of (N1,N3⋅N3,N1▪)(x) (with x=2 or 3; ⋅ represents Pt(II) and ▪ represents Pd(II)). In an extension of this work we have now prepared cis-[Pta(2)(HC-N1)(2)] (1; HC=monoanion of cytosine) and treated it with (bpy)Pd(II) (bpy=2,2'-bipyridine) to give the Pt(2) Pd(2) cycle cis-[{Pt(NH(3))(2)(N1-HC-N3)(2)Pd(bpy)}(2)](NO(3))(4) ⋅13H(2)O (5) with the coordination sites of the metals inverted; hence, platinum is bonded to N1 and palladium is bonded to N3 sites. Again, not only the expected single linkage isomer is formed, but at the same time the solid-state structure and (1)H NMR spectroscopy reveal the preferential occurrence of a single rotamer (1,3-alternate). The addition of (bpy)Pd(II) to 5 led to the formation of Pd(6) Pt(2) complex 6 in which the exocyclic N4H(2) groups of the cytosine ligands have undergone deprotonation and chelate four more (bpy)Pd(II) entities through the O2 and N4H sites. With a large excess of (bpy)Pd(II) over 5 (4:1), cis-(NH(3))(2) Pt(II) is eventually substituted by (bpy)Pd(II) to give the Pd(8) complex 7. In both 6 and 7 stacks of three (bpy)Pd(II) entities occur. The linkage isomer of 5,cis-[{Pt(NH(3))(2)(N3-HC-N1)(2)Pd(bpy)}(2)](NO(3))(4) ⋅9H(2)O (8), has been structurally characterized and the two complexes compared. The acid

  5. Gravity waves

    NASA Technical Reports Server (NTRS)

    Fritts, David

    1987-01-01

    Gravity waves contributed to the establishment of the thermal structure, small scale (80 to 100 km) fluctuations in velocity (50 to 80 m/sec) and density (20 to 30%, 0 to peak). Dominant gravity wave spectrum in the middle atmosphere: x-scale, less than 100 km; z-scale, greater than 10 km; t-scale, less than 2 hr. Theorists are beginning to understand middle atmosphere motions. There are two classes: Planetary waves and equatorial motions, gravity waves and tidal motions. The former give rise to variability at large scales, which may alter apparent mean structure. Effects include density and velocity fluctuations, induced mean motions, and stratospheric warmings which lead to the breakup of the polar vortex and cooling of the mesosphere. On this scale are also equatorial quasi-biennial and semi-annual oscillations. Gravity wave and tidal motions produce large rms fluctuations in density and velocity. The magnitude of the density fluctuations compared to the mean density is of the order of the vertical wavelength, which grows with height. Relative density fluctuations are less than, or of the order of 30% below the mesopause. Such motions may cause significant and variable convection, and wind shear. There is a strong seasonal variation in gravity wave amplitude. Additional observations are needed to address and quantify mean and fluctuation statistics of both density and mean velocity, variability of the mean and fluctuations, and to identify dominant gravity wave scales and sources as well as causes of variability, both temporal and geographic.

  6. Wave Meteorology and Soaring

    NASA Technical Reports Server (NTRS)

    Wiley, Scott

    2008-01-01

    This viewgraph document reviews some mountain wave turbulence and operational hazards while soaring. Maps, photographs, and satellite images of the meteorological phenomena are included. Additionally, photographs of aircraft that sustained mountain wave damage are provided.

  7. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  8. Particle motions beneath irrotational water waves

    NASA Astrophysics Data System (ADS)

    Bakhoday-Paskyabi, Mostafa

    2015-08-01

    Neutral and buoyant particle motions in an irrotational flow are investigated under the passage of linear, nonlinear gravity, and weakly nonlinear solitary waves at a constant water depth. The developed numerical models for the particle trajectories in a non-turbulent flow incorporate particle momentum, size, and mass (i.e., inertial particles) under the influence of various surface waves such as Korteweg-de Vries waves which admit a three parameter family of periodic cnoidal wave solutions. We then formulate expressions of mass-transport velocities for the neutral and buoyant particles. A series of test cases suggests that the inertial particles possess a combined horizontal and vertical drifts from the locations of their release, with a fall velocity as a function of particle material properties, ambient flow, and wave parameters. The estimated solutions exhibit good agreement with previously explained particle behavior beneath progressive surface gravity waves. We further investigate the response of a neutrally buoyant water parcel trajectories in a rotating fluid when subjected to a series of wind and wave events. The results confirm the importance of the wave-induced Coriolis-Stokes force effect in both amplifying (destroying) the pre-existing inertial oscillations and in modulating the direction of the flow particles. Although this work has mainly focused on wave-current-particle interaction in the absence of turbulence stochastic forcing effects, the exercise of the suggested numerical models provides additional insights into the mechanisms of wave effects on the passive trajectories for both living and nonliving particles such as swimming trajectories of plankton in non-turbulent flows.

  9. Gravity Waves

    NASA Technical Reports Server (NTRS)

    Vanzandt, T. E.

    1985-01-01

    Atmospheric parameters fluctuate on all scales. In the mesoscale these fluctuations are occasionally sinusoidal so that they can be interpreted as gravity waves. Usually, however, the fluctuations are noise like, so that their cause is not immediately evident. Results of mesoscale observations in the 20 to 120 m altitude range that are suitable for incorporation into a model atmosphere are very limited. In the stratosphere and lower mesosphere observations are sparse and very little data has been summarized into appropriate form. There is much more data in the upper mesosphere and lower thermosphere, but again very little of it has been summarized. The available mesoscale spectra of horizontal wind u versus vertical wave number m in the 20 to 120 km altitude range are shown together with a spectrum from the lower atmosphere for comparison. Further information about these spectra is given. In spite of the large range of altitudes and latitudes, the spectra from the lower atmosphere (NASA, 1971 and DEWAN, 1984) are remarkably similar in both shape and amplitude. The mean slopes of -2.38 for the NASA spectrum and -2.7 for the Dewan spectra are supported by the mean slope of -2.75 found by ROSENBERG et al. (1974). The mesospheric spectrum is too short to establish a shape. Its amplitude is about an order of magnitude larger than the NASA spectrum in the same wave number range. The NASA and Dewan spectra suggest that the mesoscale spectra in the lower atmosphere are insensitive to meteorological conditions.

  10. A Study of Alfven Wave Propagation and Heating the Chromosphere

    NASA Astrophysics Data System (ADS)

    Tu, J.; Song, P.

    2013-12-01

    Alfven wave propagation, reflection and heating of the solar atmosphere are studied for a one-dimensional solar atmosphere by self-consistently solving plasma and neutral fluid equations and Maxwell's equations with incorporation of the Hall effect, strong electron-neutral, electron-ion, and ion-neutral collisions. The governing equations are very stiff because of the strong coupling between the charged and neutral fluids. We have developed a numerical model based on an implicit backward difference formula (BDF2) of second order accuracy both in time and space to overcome the stiffness. A non-reflecting boundary condition is applied to the top boundary of the simulation domain so that the wave reflection within the domain due to the density gradient can be unambiguously determined. It is shown that the Alfven waves are partially reflected throughout the chromosphere. The reflection is increasingly stronger at higher altitudes and the strongest reflection occurs at the transition region. The waves are damped in the lower chromosphere dominantly through Joule dissipation due to electron collisions with neutrals and ions. The heating resulting from the wave damping is strong enough to balance the radiation energy loss for the quiet chromosphere. The collisional dissipation of the Alfven waves in the weakly collisional corona is negligible. The heating rates are larger for weaker background magnetic fields. In addition, higher frequency waves are subject to heavier damping. There is an upper cutoff frequency, depending on the background magnetic field, above which the waves are completely damped. At the frequencies below which the waves are not strongly damped, the waves may be strongly reflected at the transition region. The reflected waves interacting with the upward propagating waves may produce power at their double frequencies, which leads to more damping. Due to the reflection and damping, the energy flux of the waves transmitted to the corona is one order of

  11. Nepal CRS project incorporates.

    PubMed

    1983-01-01

    The Nepal Contraceptive Retail Sales (CRS) Project, 5 years after lauching product sales in June 1978, incorporated as a private, nonprofit company under Nepalese management. The transition was finalized in August 1983. The Company will work through a cooperative agreement with USAID/Kathmandu to complement the national family planning goals as the program continues to provide comtraceptives through retail channels at subsidized prices. Company objectives include: increase contraceptive sales by at least 15% per year; make CRS cost effective and move towards self sufficiency; and explore the possibility of marketing noncontraceptive health products to improve primary health care. After only5 years the program can point to some impressive successes. The number of retial shops selling family planning products increased from 100 in 1978 to over 8000, extending CRS product availability to 66 of the country's 75 districts. Retail sales have climbed dramatically in the 5-year period, from Rs 46,817 in 1978 to Rs 271,039 in 1982. Sales in terms of couple year protection CYP) have grown to 24,451 CYP(1982), a 36% increase over 1980 CYP. Since the beginning of the CRS marketing program, total distribution of contraceptives--through both CRS and the Family Planning Maternal and Child Haelth (FP/MCH) Project--has been increasing. While the FP/MCH program remains the largest distributor,contribution of CRS Products is increasing, indicating that CRS is creating new product acceptors. CRS market share in 1982 was 43% for condoms and 16% for oral contraceptives (OCs). CRS markets 5 products which are subsidized in order to be affordable to consumers as well as attractive to sellers. The initial products launched in June 1978 were Gulaf standard dose OCs and Dhaal lubricated colored condoms. A less expensive lubricates, plain Suki-Dhaal condom was introduced in June 1980 in an attempt to reach poorer rural populations, but rural distribution costs are excessive and Suki

  12. Towards improved NDE and SHM methodologies incorporating nonlinear structural features

    NASA Astrophysics Data System (ADS)

    Chillara, Vamshi Krishna

    Ultrasound is widely employed in Nondestructive Evaluation (NDE) and Structural Health Monitoring (SHM) applications to detect and characterize damage/defects in materials. In particular, ultrasonic guided waves are considered a foremost candidate for in-situ monitoring applications. Conventional ultrasonic techniques rely on changes/discontinuities in linear elastic material properties, namely the Young's modulus and shear modulus to detect damage. On the other hand, nonlinear ultrasonic techniques that rely on micro-scale nonlinear material/structural behavior are proven to be sensitive to damage induced microstructural changes that precede macro-scale damage and are hence capable of early damage detection. The goal of this thesis is to investigate the capabilities of nonlinear guided waves --- a fusion of nonlinear ultrasonic techniques with the guided wave methodologies for early damage detection. To that end, the thesis focuses on two important aspects of the problem: 1. Wavemechanics - deals with ultrasonic guided wave propagation in nonlinear waveguides; 2. Micromechanics - deals with correlating ultrasonic response with micro-scale nonlinear material behavior. For the development of efficient NDE and SHM methodologies that incorporate nonlinear structural features, a detailed understanding of the above aspects is indispensable. In this thesis, the wavemechanics aspect of the problem is dealt with from both theoretical and numerical standpoints. A generalized theoretical framework is developed to study higher harmonic guided waves in plates. This was employed to study second harmonic guided waves in pipes using a large-radius asymptotic approximation. Second harmonic guided waves in plates are studied from a numerical standpoint. Theoretical predictions are validated and some key aspects of higher harmonic generation in waveguides are outlined. Finally, second harmonic guided waves in plates with inhomogeneous and localized nonlinearities are studied and

  13. Efficacy of Combined Endoscopic Lithotomy and Extracorporeal Shock Wave Lithotripsy, and Additional Electrohydraulic Lithotripsy Using the SpyGlass Direct Visualization System or X-Ray Guided EHL as Needed, for Pancreatic Lithiasis

    PubMed Central

    Ito, Ken; Igarashi, Yoshinori; Okano, Naoki; Mimura, Takahiko; Kishimoto, Yui; Hara, Seiichi; Takuma, Kensuke

    2014-01-01

    Introduction. To evaluate the efficacy of combined endoscopic lithotomy and extracorporeal shock wave lithotripsy (ESWL), and additional electrohydraulic lithotripsy (EHL) as needed, for the treatment of pancreatic duct stones, we retrospectively evaluated 98 patients with chronic pancreatitis and pancreatic lithiasis. Methods. For the management of main pancreatic duct (MPD) stones in 98 patients, we performed combined endoscopic treatment (ET)/ESWL therapy as the first treatment option. When combined ET/ESWL was unsuccessful, EHL with the SpyGlass Direct Visualization system or X-ray guided EHL was performed. Outpatient ESWL was reserved as one of the final treatment options. Results. Fragmentation was successful in 80 (81.6%) patients as follows: combined ET/ESWL: 67 cases; SpyGlass EHL: 4 cases; X-ray guided EHL: 3 cases; and outpatient ESWL: 6 cases. Successful outcome was obtained by combined ET/ESWL in 67 of the 98 patients (74.5%), by EHL in 7 of 14 patients (7.1%), and by outpatient ESWL in 6 of 6 patients (6.1%). Negotiating the guidewire through a severe MPD stricture was significantly associated with a higher rate of stone fragmentation (P = 0.0003). Conclusions. In cases where combined ET/ESWL was not successful for stone clearance, EHL using the SpyGlass system or X-ray guided EHL was effective in cases where the guidewire could be negotiated through the MPD stricture and it increased the fragmentation rate. PMID:24999474

  14. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  15. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  16. Ring Current-Electromagnetic Ion Cyclotron Waves Coupling

    NASA Technical Reports Server (NTRS)

    Khazanov, G. V.

    2005-01-01

    The effect of Electromagnetic Ion Cyclotron (EMIC) waves, generated by ion temperature anisotropy in Earth s ring current (RC), is the best known example of wave- particle interaction in the magnetosphere. Also, there is much controversy over the importance of EMIC waves on RC depletion. Under certain conditions, relativistic electrons, with energies 21 MeV, can be removed from the outer radiation belt (RB) by EMIC wave scattering during a magnetic storm. That is why the calculation of EMIC waves must be a very critical part of the space weather studies. The new RC model that we have developed and present for the first time has several new features that we have combine together in a one single model: (a) several lower frequency cold plasma wave modes are taken into account; (b) wave tracing of these wave has been incorporated in the energy EMIC wave equation; (c) no assumptions regarding wave shape spectra have been made; (d) no assumptions regarding the shape of particle distribution have been made to calculate the growth rate; (e) pitch-angle, energy, and mix diffusions are taken into account together for the first time; (f) the exact loss-cone RC analytical solution has been found and coupled with bounce-averaged numerical solution of kinetic equation; (g) the EMIC waves saturation due to their modulation instability and LHW generation are included as an additional factor that contributes to this process; and (h) the hot ions were included in the real part of dielectric permittivity tensor. We compare our theoretical results with the different EMIC waves models as well as RC experimental data.

  17. Impacts of wave spreading and multidirectional waves on estimating Stokes drift

    NASA Astrophysics Data System (ADS)

    Webb, A.; Fox-Kemper, B.

    2015-12-01

    The Stokes drift, and its leading-order approximation, for a random sea depend upon the interaction of different wave groups and the process of wave spreading. Here Stokes drift direction and magnitude from prescribed spectra, local observational buoy data, and global model WAVEWATCH III output are used to analyze approximations of Stokes drift for directional random seas in deep water. To facilitate analysis, a new approximation is defined to incorporate the systematic effects of wave spreading. Stokes drift is typically overestimated by ignoring these effects or by ignoring directional differences in swell and wind seas. These two errors are differentiated and found to be largely uncorrelated. These errors depend strongly on depth, with deeper Stokes drift favoring narrow-banded swell and shallower Stokes drift favoring wind seas. Results are consistent among the data examined. Mean Stokes drift magnitude reductions from wave spreading and multidirectional wave effects alone are 14-20% and 7-23% respectively, giving a combined reduction of 20-40% versus unidirectional waves, depending on wave age and depth. Approximations that do not include these reductions however, will on average overestimate Stokes drift by 16-26%, 26-43%, and 45-71% respectively. In addition to magnitude, the direction of Stokes drift is also affected and multidirectional waves generate a directional veer with depth: the 30/60/90% confidence intervals are bounded (approximately) by ± 0.12/0.28/0.84 radians (± 7/16/48 deg) at the surface, with smaller intervals at depth. Complementary depth-integrated approximations are also investigated and directional effects are similar with depth-dependent subsurface results. Furthermore, an optimized directional spread correction for the surface is nearly identical for global simulations and a buoy located at Ocean Weather Station P (50°N 145°W), and does not require directional wave spectrum data.

  18. Propagation of seismic waves in tall buildings

    USGS Publications Warehouse

    Safak, E.

    1998-01-01

    A discrete-time wave propagation formulation of the seismic response of tall buildings is introduced. The building is modeled as a layered medium, similar to a layered soil medium, and is subjected to vertically propagating seismic shear waves. Soil layers and the bedrock under the foundation are incorporated in the formulation as additional layers. Seismic response is expressed in terms of the wave travel times between the layers, and the wave reflection and transmission coefficients at the layer interfaces. The equations account for the frequency-dependent filtering effects of the foundation and floor masses. The calculation of seismic response is reduced to a pair of simple finite-difference equations for each layer, which can be solved recursively starting from the bedrock. Compared to the commonly used vibration formulation, the wave propagation formulation provides several advantages, including simplified calculations, better representation of damping, ability to account for the effects of the soil layers under the foundation, and better tools for identification and damage detection from seismic records. Examples presented show the versatility of the method. ?? 1998 John Wiley & Sons, Ltd.

  19. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  20. Characterization of active paper packaging incorporated with ginger pulp oleoresin

    NASA Astrophysics Data System (ADS)

    Wiastuti, T.; Khasanah, L. U.; Atmaka Kawiji, W.; Manuhara, G. J.; Utami, R.

    2016-02-01

    Utilization of ginger pulp waste from herbal medicine and instant drinks industry in Indonesia currently used for fertilizer and fuel, whereas the ginger pulp still contains high oleoresin. Active paper packaging were developed incorporated with ginger pulp oleoresin (0%, 2%, 4%, and 6% w/w). Physical (thickness, tensile strength, and folding endurance, moisture content), sensory characteristics and antimicrobial activity of the active paper were evaluated. Selected active paper then were chemically characterized (functional groups). The additional of ginger pulp oleoresin levels are reduced tensile strength, folding endurance and sensory characteristic (color, texture and overall) and increased antimicrobial activity. Due to physical, sensory characteristic and antimicrobial activity, active paper with 2% ginger pulp oleoresin incorporation was selected. Characteristics of selected paper were 9.93% of water content; 0.81 mm of thickness; 0.54 N / mm of tensile strength; 0.30 of folding endurance; 8.43 mm inhibits the growth of Pseudomonas fluorescence and 27.86 mm inhibits the growth of Aspergillus niger (antimicrobial activity) and neutral preference response for sensory properties. For chemical characteristic, selected paper had OH functional group of ginger in 3422.83 cm-1 of wave number and indicated contain red ginger active compounds.

  1. Biological effects of laser-induced stress waves

    SciTech Connect

    Doukas, A.; Lee, S.; McAuliffe, D.

    1995-12-31

    Laser-induced stress waves can be generated by one of the following mechanisms: Optical breakdown, ablation or rapid heating of an absorbing medium. These three modes of laser interaction with matter allow the investigation of cellular and tissue responses to stress waves with different characteristics and under different conditions. The most widely studied phenomena are those of the collateral damage seen in photodisruption in the eye and in 193 run ablation of cornea and skin. On the other hand, the therapeutic application of laser-induced stress waves has been limited to the disruption of noncellular material such as renal stones, atheromatous plaque and vitreous strands. The effects of stress waves to cells and tissues can be quite disparate. Stress waves can fracture tissue, damage cells, and increase the permeability of the plasma membrane. The viability of cell cultures exposed to stress waves increases with the peak stress and the number of pulses applied. The rise time of the stress wave also influences the degree of cell injury. In fact, cell viability, as measured by thymidine incorporation, correlates better with the stress gradient than peak stress. Recent studies have also established that stress waves induce a transient increase of the permeability of the plasma membrane in vitro. In addition, if the stress gradient is below the damage threshhold, the cells remain viable. Thus, stress waves can be useful as a means of drug delivery, increasing the intracellular drug concentration and allowing the use of drugs which are impermeable to the cell membrane. The present studies show that it is important to create controllable stress waves. The wavelength tunability and the micropulse structure of the free electron laser is ideal for generating stress waves with independently adjustable parameters, such as rise time, duration and peak stress.

  2. Ring Current Dynamic in the Presence of EMIC Waves

    NASA Technical Reports Server (NTRS)

    Khazanov, G. V.; Gamayunov, K. V.

    2005-01-01

    The effect of EMIC waves, generated by a positive ion temperature anisotropy on Earth s RC ions is one of the best known examples of wave-particle interaction in the magnetosphere and the most controversial mechanism of RC losses. Under certain conditions, relativistic electrons with energy 21 MeV can be removed from the outer RB by EMIC wave scattering during a magnetic storm much faster than by any other loss mechanisms. That is why the calculation of EMIC waves is a very critical part of the NASA LWS program. The new RC model that we have developed and present for the first time has several new features that we have combine together in a one single model: (a) several lower frequency cold plasma wave modes are taken into account; (b) wave tracing of these wave has been incorporated in the energy EMIC wave equation; (c) no assumptions regarding wave shape spectra have been made; (d) no assumptions regarding the shape of particle distribution have been made to calculate the growth rate; (e) pitch- angle, energy, and mix diffusions are taken into account together for the first time; (f) the exact loss-cone RC analytical solution has been found and coupled with bounce-averaged numerical solution of kinetic equation; (g) LHW are included as an additional factor that contributes to saturation process of EMIC waves; and (h) the hot ions were included in the real part of dielectric permittivity tensor. We compare our theoretical results with the different EMIC waves models as well as RC experimental data.

  3. Making Waves.

    ERIC Educational Resources Information Center

    DeClark, Tom

    2000-01-01

    Presents an activity on waves that addresses the state standards and benchmarks of Michigan. Demonstrates waves and studies wave's medium, motion, and frequency. The activity is designed to address different learning styles. (YDS)

  4. Spectral-Element Simulations of Wave Propagation in Porous Media

    NASA Astrophysics Data System (ADS)

    Morency, C.; Tromp, J.

    2007-12-01

    Biot theory has been extensively used in the petroleum industry, where seismic surveys are performed to determine the physical properties of reservoir rocks. The theory is also of broad general interest when a physical understanding of the coupling between solid and fluid phases is desired. One fundamental result of Biot theory is the prediction of a second compressional wave, which attenuates rapidly, often referred to as "type II" or "Biot's slow compressional wave", in addition to the classical fast compressional and shear waves. The mathematical formulation of wave propagation in porous media developed by Biot is based upon the principle of virtual work, ignoring processes at the microscopic level. Moreover, even if the Biot formulations are claimed to be valid for non-uniform porosity, gradients in porosity are not explicitly incorporated in the original theory. More recent studies focused on averaging techniques to derive the macroscopic porous medium equations from the microscale, and made an attempt to derive an expression for the change in porosity, but there is still room for clarification of such an expression, and to properly integrate the effects of gradients in porosity. We aim to present a straightforward derivation of the main equations describing wave propagation in porous media, with a particular emphasis on the effects of gradients in porosity. We also present a two dimensional numerical implementation of these equations using a spectral-element method. Finally, we have performed different benchmarks to validate our method, involving acoustic-poroelastic waves interaction and wave propagation in heterogenous porous media.

  5. Promoting Additive Acculturation in Schools.

    ERIC Educational Resources Information Center

    Gibson, Margaret A.

    1995-01-01

    A study focusing on 113 ninth graders of Mexican descent indicates that most students and their parents adhere to a strategy of additive acculturation (incorporating skills of the new culture and language), but that the school curriculum and general school climate devalue Mexican culture. (SLD)

  6. Gravitational Wave Propulsion

    NASA Astrophysics Data System (ADS)

    Fontana, Giorgio

    2005-02-01

    There is only one experimental proof that gravitational waves exist. With such a limitation, it may seem premature to suggest the possibility that gravitational waves can became a preferred space propulsion technique. The present understanding of the problem indicates that this is not the case. The emission of gravitational waves from astrophysical sources has been confirmed by observation, the respective detection at large distance from the source is difficult and actually we have no confirmation of a successful detection. Therefore the required preliminary discovery has been already made. This opinion is enforced by many different proposals for building the required powerful gravitational wave generators that have recently appeared in the literature and discussed at conferences. It is no longer reasonable to wait for additional confirmation of the existence of gravitational waves to start a program for building generators and testing their possible application to space travel. A vast literature shows that gravitational waves can be employed for space propulsion. Gravitational wave rockets have been proposed, non-linearity of Einstein equations allows the conversion of gravitational waves to a static gravitational field and ``artificial gravity assist'' may become a new way of travelling in space-time. Different approaches to gravitational wave propulsion are reviewed and compared. Gravitational wave propulsion is also compared to traditional rocket propulsion and an undeniable advantage can be demonstrated in terms of efficiency and performance. Testing the predictions will require gravitational wave generators with high power and wavelength short enough for producing high energy densities. Detectors designed for the specific application must be developed, taking into account that non-linearity effects are expected. The study and development of Gravitational wave propulsion is a very challenging endeavor, involving the most complex theories, sophisticated

  7. Cycloidal Wave Energy Converter

    SciTech Connect

    Stefan G. Siegel, Ph.D.

    2012-11-30

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will

  8. Wave rotor demonstrator engine assessment

    NASA Technical Reports Server (NTRS)

    Snyder, Philip H.

    1996-01-01

    The objective of the program was to determine a wave rotor demonstrator engine concept using the Allison 250 series engine. The results of the NASA LERC wave rotor effort were used as a basis for the wave rotor design. A wave rotor topped gas turbine engine was identified which incorporates five basic requirements of a successful demonstrator engine. Predicted performance maps of the wave rotor cycle were used along with maps of existing gas turbine hardware in a design point study. The effects of wave rotor topping on the engine cycle and the subsequent need to rematch compressor and turbine sections in the topped engine were addressed. Comparison of performance of the resulting engine is made on the basis of wave rotor topped engine versus an appropriate baseline engine using common shaft compressor hardware. The topped engine design clearly demonstrates an impressive improvement in shaft horsepower (+11.4%) and SFC (-22%). Off design part power engine performance for the wave rotor topped engine was similarly improved including that at engine idle conditions. Operation of the engine at off design was closely examined with wave rotor operation at less than design burner outlet temperatures and rotor speeds. Challenges identified in the development of a demonstrator engine are discussed. A preliminary design was made of the demonstrator engine including wave rotor to engine transition ducts. Program cost and schedule for a wave rotor demonstrator engine fabrication and test program were developed.

  9. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  10. Millimeter Wave Holographical Inspection of Honeycomb Composites

    NASA Technical Reports Server (NTRS)

    Case, J. T.; Kharkovsky, S.; Zoughi, R.; Stefes, G.; Hepburn, Frank L.; Hepburn, Frank L.

    2007-01-01

    Multi-layered composite structures manufactured with honeycomb, foam or balsa wood cores are finding increasing utility in a variety of aerospace, transportation, and infrastructure applications. Due to the low conductivity and inhomogeneity associated with these composites standard nondestructive testing (NDT) methods are not always capable of inspecting their interior for various defects caused during the manufacturing process or as a result of in-service loading. On the contrary, microwave and millimeter wave NDT methods are well-suited for inspecting these structures since signals at these frequencies readily penetrate through these structures and reflect from different interior boundaries revealing the presence of a wide range of defects such as disbond, delamination, moisture and oil intrusion, impact damage, etc. Millimeter wave frequency spectrum spans 30 GHz - 300 GHz with corresponding wavelengths of 10 - 1 mm. Due to the inherent short wavelengths at these frequencies, one can produce high spatial resolution images of these composites either using real-antenna focused or synthetic-aperture focused methods. In addition, incorporation of swept-frequency in the latter method (i.e., holography) results in high-resolution three-dimensional images. This paper presents the basic steps behind producing such images at millimeter wave frequencies and the results of two honeycomb composite panels are demonstrated at Q-band (33-50 GHz). In addition, these results are compared to previous results using X-ray computed tomography.

  11. Wave turbulence

    NASA Astrophysics Data System (ADS)

    Nazarenko, Sergey

    2015-07-01

    Wave turbulence is the statistical mechanics of random waves with a broadband spectrum interacting via non-linearity. To understand its difference from non-random well-tuned coherent waves, one could compare the sound of thunder to a piece of classical music. Wave turbulence is surprisingly common and important in a great variety of physical settings, starting with the most familiar ocean waves to waves at quantum scales or to much longer waves in astrophysics. We will provide a basic overview of the wave turbulence ideas, approaches and main results emphasising the physics of the phenomena and using qualitative descriptions avoiding, whenever possible, involved mathematical derivations. In particular, dimensional analysis will be used for obtaining the key scaling solutions in wave turbulence - Kolmogorov-Zakharov (KZ) spectra.

  12. Project GlobWave

    NASA Astrophysics Data System (ADS)

    Busswell, Geoff; Ash, Ellis; Piolle, Jean-Francois; Poulter, David J. S.; Snaith, Helen; Collard, Fabrice; Sheera, Harjit; Pinnock, Simon

    2010-12-01

    The ESA GlobWave project is a three year initiative, funded by ESA and CNES, to service the needs of satellite wave product users across the globe. Led by Logica UK, with support from CLS, IFREMER, SatOC and NOCS, the project will provide free access to satellite wave data and products in a common format, both historical and in near real time, from various European and American SAR and altimeter missions. Building on the successes of similar projects for Sea Surface Temperature and ocean colour, the project aims to stimulate increased use and analysis of satellite wave products. In addition to common-format satellite data the project will provide comparisons with in situ measurements, interactive data analysis tools and a pilot spatial wave forecast verification scheme for operational forecast production centres. The project will begin operations in January 2010, with direction from regular structured user consultation.

  13. Denitrification incorporating microporous membranes

    SciTech Connect

    Reising, A.R.; Schroeder, E.D.

    1996-07-01

    A microbial system for removal of nitrate from drinking water in which the denitrification reactions are physically separated from the water being treated by a microporous membrane was studied. The experimental system was composed of two equal-volume cells separated by a 0.02 {mu}m pore size polytetrafluoroethylene membrane. No pressure difference existed across the membrane, and nitrate ions were transported through the membrane by diffusion. Results of experiments with biofilm denitrification and suspended-culture systems are presented. Deoxygenation by N{sub 2} stripping and by SO{sub 3}{sup {minus}2} produced equivalent results. Removal rates with the suspended culture systems were greater than those with biofilms. Effective membrane diffusivities calculated for suspended-culture systems were approximately the same as for sterile systems, indicating that resistance to transport was not changed by the addition of the suspended microbial culture. The methanol requirement observed in the experiments was 1.4 g total organic carbon (TOC) per g NO{sub 3}{sup {minus}}-N removed. Removal rates followed first-order pseudotransport controlled models for both the biofilm and suspended-culture systems. A prototype continuous-flow system is presented.

  14. Gravity Waves

    Atmospheric Science Data Center

    2013-04-19

    article title:  Gravity Waves Ripple over Marine Stratocumulus Clouds ... Imaging SpectroRadiometer (MISR), a fingerprint-like gravity wave feature occurs over a deck of marine stratocumulus clouds. Similar ... that occur when a pebble is thrown into a still pond, such "gravity waves" sometimes appear when the relatively stable and stratified air ...

  15. Additive concentrates for distillate fuels

    SciTech Connect

    Rossi, A.; Lewtas, K.

    1985-08-27

    An additive concentrate for incorporation into wax containing petroleum fuel oil compositions to improve low temperature flow properties comprising an oil solution containing: 3% to 90 wt. % of a C30-C300 oil-soluble nitrogen compound wax crystal growth inhibitor having at least one straight C8-C40 alkyl chain and partial esters, and at least one mole per mole of an organic acid capable of hydrogen bonding to improve the solubility in the oil.

  16. Physicochemical characterization of surfactant incorporating vesicles that incorporate colloidal magnetite.

    PubMed

    de Melo Barbosa, Raquel; Luna Finkler, Christine L; Bentley, Maria Vitória L B; Santana, Maria Helena A

    2013-03-01

    Drug administration through the transdermal route has optimized for the comfort of patients and easy application. However, the main limitation of transdermal drug delivery is the impermeability of the human skin. Recent advances on improvement of drug transport through the skin include elastic liposomes as a penetration enhancer. Entrapment of ferrofluids in the core of liposomes produces magnetoliposomes, which can be driven by a high-gradient magnetic field. The association of both strategies could enhance the penetration of elastic liposomes. This work relies on the preparation and characterization of elastic-magnetic liposomes designed to permeate through the skin. The incorporation of colloidal magnetite and the elastic component, octaethylene glycol laurate (PEG-8-L), in the structure of liposomes were evaluated. The capability of the elastic magnetoliposomes for permeation through nanopores of two stacked polycarbonate membranes was compared to conventional and elastic liposomes. Magnetite incorporation was dependent on vesicle diameter and size distribution as well as PEG-8-L incorporation into liposomes, demonstrating the capability of the fluid bilayer to accommodate the surfactant without disruption. On the contrary, PEG-8-L incorporation into magnetoliposomes promoted a decrease of average diameter and a lower PEG-8-L incorporation percentage as a result of reduction on the fluidity of the bilayer imparted by iron incorporation into the lipid structure. Elastic liposomes demonstrated an enhancement of the deformation capability, as compared with conventional liposomes. Conventional and elastic magnetoliposomes presented a reduced capability for deformation and permeation. PMID:23363304

  17. Model for small arms fire muzzle blast wave propagation in air

    NASA Astrophysics Data System (ADS)

    Aguilar, Juan R.; Desai, Sachi V.

    2011-11-01

    Accurate modeling of small firearms muzzle blast wave propagation in the far field is critical to predict sound pressure levels, impulse durations and rise times, as functions of propagation distance. Such a task being relevant to a number of military applications including the determination of human response to blast noise, gunfire detection and localization, and gun suppressor design. Herein, a time domain model to predict small arms fire muzzle blast wave propagation is introduced. The model implements a Friedlander wave with finite rise time which diverges spherically from the gun muzzle. Additionally, the effects in blast wave form of thermoviscous and molecular relaxational processes, which are associated with atmospheric absorption of sound were also incorporated in the model. Atmospheric absorption of blast waves is implemented using a time domain recursive formula obtained from numerical integration of corresponding differential equations using a Crank-Nicholson finite difference scheme. Theoretical predictions from our model were compared to previously recorded real world data of muzzle blast wave signatures obtained by shooting a set different sniper weapons of varying calibers. Recordings containing gunfire acoustical signatures were taken at distances between 100 and 600 meters from the gun muzzle. Results shows that predicted blast wave slope and exponential decay agrees well with measured data. Analysis also reveals the persistency of an oscillatory phenomenon after blast overpressure in the recorded wave forms.

  18. GRAVITY WAVES ON HOT EXTRASOLAR PLANETS. I. PROPAGATION AND INTERACTION WITH THE BACKGROUND

    SciTech Connect

    Watkins, Chris; Cho, J. Y-K. E-mail: J.Cho@qmul.ac.u

    2010-05-01

    We study the effects of gravity waves, or g-modes, on hot extrasolar planets. These planets are expected to possess stably stratified atmospheres, which support gravity waves. In this paper, we review the derivation of the equation that governs the linear dynamics of gravity waves and describe its application to a hot extrasolar planet, using HD 209458 b as a generic example. We find that gravity waves can exhibit a wide range of behaviors, even for a single atmospheric profile. The waves can significantly accelerate or decelerate the background mean flow, depending on the difference between the wave phase and mean flow speeds. In addition, the waves can provide significant heating ({approx}10{sup 2} to {approx}10{sup 3} K per planetary rotation), especially to the region of the atmosphere above about 10 scale heights from the excitation region. Furthermore, by propagating horizontally, gravity waves provide a mechanism for transporting momentum and heat from the dayside of a tidally locked planet to its nightside. We discuss work that needs to be undertaken to incorporate these effects in current atmosphere models of extrasolar planets.

  19. Reconnections of Wave Vortex Lines

    ERIC Educational Resources Information Center

    Berry, M. V.; Dennis, M. R.

    2012-01-01

    When wave vortices, that is nodal lines of a complex scalar wavefunction in space, approach transversely, their typical crossing and reconnection is a two-stage process incorporating two well-understood elementary events in which locally coplanar hyperbolas switch branches. The explicit description of this reconnection is a pedagogically useful…

  20. Frequency coded sensors incorporating tapers

    NASA Technical Reports Server (NTRS)

    Hines, Jacqueline H. (Inventor); Solie, Leland P. (Inventor)

    2010-01-01

    A surface acoustic wave device includes a piezoelectric substrate on which is formed a transducer that generates acoustic waves on the surface of the substrate from electrical waves received by the transducer. The waves are carried along an acoustic track to either a second transducer or a reflector. The transducers or transducer and reflector are formed of subsections that are constructed to operate at mutually different frequencies. The subsections of at least one of the transducers or transducer and reflector are out of alignment with respect to one another relative to the transverse of the propagation direction. The out of aligned subsections provide not only a frequency component but also a time to the signal output signal. Frequency response characteristics are improved. An alternative embodiment provides that the transducers and/or reflectors are continuously tapered instead of having discrete frequency subsections.

  1. Integrated-optic polarization controllers incorporating polymer waveguide birefringence modulators.

    PubMed

    Kim, Jun-Whee; Park, Su-Hyun; Chu, Woo-Sung; Oh, Min-Cheol

    2012-05-21

    Polarization controllers based on polymer waveguide technology are demonstrated by incorporating thermo-optic birefringence modulators (BMs) and thin-film wave plates. Highly birefringent polymer materials are used to increase the efficiency of birefringence modulation in proportion to the heating power. Thin-film quarter-wave plates are fabricated by using a crosslinkable liquid crystal, reactive mesogen, and inserted between the BMs to produce static phase retardation and polarization coupling. By applying a triangular AC signal to one BM and a DC signal to another, the polarization states of the output light are modulated to cover the entire surface of the Poincaré sphere. PMID:22714231

  2. Benefits of oxygen incorporation in atomic laminates

    NASA Astrophysics Data System (ADS)

    Dahlqvist, Martin

    2016-04-01

    Atomic laminates such as MAX phases benefit from the addition of oxygen in many ways, from the formation of a protective oxide surface layer with self-healing capabilities when cracks form to the tuning of anisotropic conductivity. In this paper oxygen incorporation and vacancy formation in M 2AlC (M  =  Ti, V, Cr) MAX phases have been studied using first-principles calculations where the focus is on phase stability and electronic structure for different oxygen and/or vacancy configurations. Oxygen prefers different lattice sites depending on M-element and this can be correlated to the number of available non-bonding M d-electrons. In Ti2AlC, oxygen substitutes carbon while in Cr2AlC it is located interstitially within the Al-layer. I predict that oxygen incorporation in Ti2AlC stabilizes the material, which explains the experimentally observed 12.5 at% oxygen (x  =  0.5) in Ti2Al(C1‑x O x ). In addition, it is also possible to use oxygen to stabilize the hypothetical Zr2AlC and Hf2AlC. Hence, oxygen incorporation may be beneficial in many ways. Not only can it make a material more stable, but it also can act as a reservoir for internal self-healing with shorter diffusion paths.

  3. Fundamental plasma emission involving ion sound waves

    NASA Technical Reports Server (NTRS)

    Cairns, Iver H.

    1987-01-01

    The theory for fundamental plasma emission by the three-wave processes L + or - S to T (where L, S and T denote Langmuir, ion sound and transverse waves, respectively) is developed. Kinematic constraints on the characteristics and growth lengths of waves participating in the wave processes are identified. In addition the rates, path-integrated wave temperatures, and limits on the brightness temperature of the radiation are derived.

  4. On wave radar measurement

    NASA Astrophysics Data System (ADS)

    Ewans, Kevin; Feld, Graham; Jonathan, Philip

    2014-09-01

    The SAAB REX WaveRadar sensor is widely used for platform-based wave measurement systems by the offshore oil and gas industry. It offers in situ surface elevation wave measurements at relatively low operational costs. Furthermore, there is adequate flexibility in sampling rates, allowing in principle sampling frequencies from 1 to 10 Hz, but with an angular microwave beam width of 10° and an implied ocean surface footprint in the order of metres, significant limitations on the spatial and temporal resolution might be expected. Indeed there are reports that the accuracy of the measurements from wave radars may not be as good as expected. We review the functionality of a WaveRadar using numerical simulations to better understand how WaveRadar estimates compare with known surface elevations. In addition, we review recent field measurements made with a WaveRadar set at the maximum sampling frequency, in the light of the expected functionality and the numerical simulations, and we include inter-comparisons between SAAB radars and buoy measurements for locations in the North Sea.

  5. Undamped electrostatic plasma waves

    SciTech Connect

    Valentini, F.; Perrone, D.; Veltri, P.; Califano, F.; Pegoraro, F.; Morrison, P. J.; O'Neil, T. M.

    2012-09-15

    Electrostatic waves in a collision-free unmagnetized plasma of electrons with fixed ions are investigated for electron equilibrium velocity distribution functions that deviate slightly from Maxwellian. Of interest are undamped waves that are the small amplitude limit of nonlinear excitations, such as electron acoustic waves (EAWs). A deviation consisting of a small plateau, a region with zero velocity derivative over a width that is a very small fraction of the electron thermal speed, is shown to give rise to new undamped modes, which here are named corner modes. The presence of the plateau turns off Landau damping and allows oscillations with phase speeds within the plateau. These undamped waves are obtained in a wide region of the (k,{omega}{sub R}) plane ({omega}{sub R} being the real part of the wave frequency and k the wavenumber), away from the well-known 'thumb curve' for Langmuir waves and EAWs based on the Maxwellian. Results of nonlinear Vlasov-Poisson simulations that corroborate the existence of these modes are described. It is also shown that deviations caused by fattening the tail of the distribution shift roots off of the thumb curve toward lower k-values and chopping the tail shifts them toward higher k-values. In addition, a rule of thumb is obtained for assessing how the existence of a plateau shifts roots off of the thumb curve. Suggestions are made for interpreting experimental observations of electrostatic waves, such as recent ones in nonneutral plasmas.

  6. Emissive sensors and devices incorporating these sensors

    DOEpatents

    Swager, Timothy M; Zhang, Shi-Wei

    2013-02-05

    The present invention generally relates to luminescent and/or optically absorbing compositions and/or precursors to those compositions, including solid films incorporating these compositions/precursors, exhibiting increased luminescent lifetimes, quantum yields, enhanced stabilities and/or amplified emissions. The present invention also relates to sensors and methods for sensing analytes through luminescent and/or optically absorbing properties of these compositions and/or precursors. Examples of analytes detectable by the invention include electrophiles, alkylating agents, thionyl halides, and phosphate ester groups including phosphoryl halides, cyanides and thioates such as those found in certain chemical warfare agents. The present invention additionally relates to devices and methods for amplifying emissions, such as those produced using the above-described compositions and/or precursors, by incorporating the composition and/or precursor within a polymer having an energy migration pathway. In some cases, the compositions and/or precursors thereof include a compound capable of undergoing a cyclization reaction.

  7. Do calcium buffers always slow down the propagation of calcium waves?

    PubMed

    Tsai, Je-Chiang

    2013-12-01

    Calcium buffers are large proteins that act as binding sites for free cytosolic calcium. Since a large fraction of cytosolic calcium is bound to calcium buffers, calcium waves are widely observed under the condition that free cytosolic calcium is heavily buffered. In addition, all physiological buffered excitable systems contain multiple buffers with different affinities. It is thus important to understand the properties of waves in excitable systems with the inclusion of buffers. There is an ongoing controversy about whether or not the addition of calcium buffers into the system always slows down the propagation of calcium waves. To solve this controversy, we incorporate the buffering effect into the generic excitable system, the FitzHugh-Nagumo model, to get the buffered FitzHugh-Nagumo model, and then to study the effect of the added buffer with large diffusivity on traveling waves of such a model in one spatial dimension. We can find a critical dissociation constant (K = K(a)) characterized by system excitability parameter a such that calcium buffers can be classified into two types: weak buffers (K ∈ (K(a), ∞)) and strong buffers (K ∈ (0, K(a))). We analytically show that the addition of weak buffers or strong buffers but with its total concentration b(0)(1) below some critical total concentration b(0,c)(1) into the system can generate a traveling wave of the resulting system which propagates faster than that of the origin system, provided that the diffusivity D1 of the added buffers is sufficiently large. Further, the magnitude of the wave speed of traveling waves of the resulting system is proportional to √D1 as D1 --> ∞. In contrast, the addition of strong buffers with the total concentration b(0)(1) > b(0,c)(1) into the system may not be able to support the formation of a biologically acceptable wave provided that the diffusivity D1 of the added buffers is sufficiently large.

  8. Wave Engine Topping Cycle Assessment

    NASA Technical Reports Server (NTRS)

    Welch, Gerard E.

    1996-01-01

    The performance benefits derived by topping a gas turbine engine with a wave engine are assessed. The wave engine is a wave rotor that produces shaft power by exploiting gas dynamic energy exchange and flow turning. The wave engine is added to the baseline turboshaft engine while keeping high-pressure-turbine inlet conditions, compressor pressure ratio, engine mass flow rate, and cooling flow fractions fixed. Related work has focused on topping with pressure-exchangers (i.e., wave rotors that provide pressure gain with zero net shaft power output); however, more energy can be added to a wave-engine-topped cycle leading to greater engine specific-power-enhancement The energy addition occurs at a lower pressure in the wave-engine-topped cycle; thus the specific-fuel-consumption-enhancement effected by ideal wave engine topping is slightly lower than that effected by ideal pressure-exchanger topping. At a component level, however, flow turning affords the wave engine a degree-of-freedom relative to the pressure-exchanger that enables a more efficient match with the baseline engine. In some cases, therefore, the SFC-enhancement by wave engine topping is greater than that by pressure-exchanger topping. An ideal wave-rotor-characteristic is used to identify key wave engine design parameters and to contrast the wave engine and pressure-exchanger topping approaches. An aerodynamic design procedure is described in which wave engine design-point performance levels are computed using a one-dimensional wave rotor model. Wave engines using various wave cycles are considered including two-port cycles with on-rotor combustion (valved-combustors) and reverse-flow and through-flow four-port cycles with heat addition in conventional burners. A through-flow wave cycle design with symmetric blading is used to assess engine performance benefits. The wave-engine-topped turboshaft engine produces 16% more power than does a pressure-exchanger-topped engine under the specified topping

  9. Lamb Wave Response of Fatigued Composite Samples

    NASA Technical Reports Server (NTRS)

    Seale, Michael; Smith, Barry T.; Prosser, William H.; Masters, John E.

    1994-01-01

    Composite materials are being more widely used today by aerospace, automotive, sports equipment, and a number of other commercial industries because of their advantages over conventional metals. Composites have a high strength-to-weight ratio and can be constructed to meet specific design needs. Composite structures are already in use in secondary parts of the Douglas MD-11 and are planned to be used in the new MD-12X. Plans also exist for their use in primary and secondary structures on the Boeing 777. Douglas proposed MD-XX may also incorporate composite materials into primary structures such as the wings and tail. Use of composites in these structures offers weight savings, corrosion resistance, and improved aerodynamics. Additionally, composites have been used to repair cracks in many B-1Bs where traditional repair techniques were not very effective. Plans have also been made to reinforce all of the remaining B-1s with composite materials. Verification of the structural integrity of composite components is needed to insure safe operation of these aerospace vehicles. One aspect of the use of these composites is their response to fatigue. To track this progression of fatigue in aerospace structures, a convenient method to nondestructively monitor this damage needs to be developed. Traditional NDE techniques used on metals are not easily adaptable to composites due to the inhomogeneous and anisotropic nature of these materials. Finding an effective means of nondestructively monitoring fatigue damage is extremely important to the safety and reliability of such structures. Lamb waves offer one method of evaluating these composite materials. As a material is fatigued, the modulus degrades. Since the Lamb wave velocity can be related to the modulus of the material, an effective tool can be developed to monitor fatigue damage in composites by measuring the velocity of these waves. In this work, preliminary studies have been conducted which monitor fatigue damage in

  10. Host thin films incorporating nanoparticles

    NASA Astrophysics Data System (ADS)

    Qureshi, Uzma

    The focus of this research project was the investigation of the functional properties of thin films that incorporate a secondary nanoparticulate phase. In particular to assess if the secondary nanoparticulate material enhanced a functional property of the coating on glass. In order to achieve this, new thin film deposition methods were developed, namely use of nanopowder precursors, an aerosol assisted transport technique and an aerosol into atmospheric pressure chemical vapour deposition system. Aerosol assisted chemical vapour deposition (AACVD) was used to deposit 8 series of thin films on glass. Five different nanoparticles silver, gold, ceria, tungsten oxide and zinc oxide were tested and shown to successfully deposit thin films incorporating nanoparticles within a host matrix. Silver nanoparticles were synthesised and doped within a titania film by AACVD. This improved solar control properties. A unique aerosol assisted chemical vapour deposition (AACVD) into atmospheric pressure chemical vapour deposition (APCVD) system was used to deposit films of Au nanoparticles and thin films of gold nanoparticles incorporated within a host titania matrix. Incorporation of high refractive index contrast metal oxide particles within a host film altered the film colour. The key goal was to test the potential of nanopowder forms and transfer the suspended nanopowder via an aerosol to a substrate in order to deposit a thin film. Discrete tungsten oxide nanoparticles or ceria nanoparticles within a titanium dioxide thin film enhanced the self-cleaning and photo-induced super-hydrophilicity. The nanopowder precursor study was extended by deposition of zinc oxide thin films incorporating Au nanoparticles and also ZnO films deposited from a ZnO nanopowder precursor. Incorporation of Au nanoparticles within a VO: host matrix improved the thermochromic response, optical and colour properties. Composite VC/TiC and Au nanoparticle/V02/Ti02 thin films displayed three useful

  11. Shear wave filtering in naturally-occurring Bouligand structures.

    PubMed

    Guarín-Zapata, Nicolás; Gomez, Juan; Yaraghi, Nick; Kisailus, David; Zavattieri, Pablo D

    2015-09-01

    Wave propagation was investigated in the Bouligand-like structure from within the dactyl club of the stomatopod, a crustacean that is known to smash their heavily shelled preys with high accelerations. We incorporate the layered nature in a unitary material cell through the propagator matrix formalism while the periodic nature of the material is considered via Bloch boundary conditions as applied in the theory of solid state physics. Our results show that these materials exhibit bandgaps at frequencies related to the stress pulse generated by the impact of the dactyl club to its prey, and therefore exhibiting wave filtering in addition to the already known mechanisms of macroscopic isotropic behavior and toughness. PMID:25983314

  12. Ion temperature effects on magnetotail Alfvén wave propagation and electron energization: ION TEMPERATURE EFFECTS ON ALFVÉN WAVES

    SciTech Connect

    Damiano, P. A.; Johnson, J. R.; Chaston, C. C.

    2015-07-01

    A new 2-D self-consistent hybrid gyrofluid-kinetic electron model in dipolar coordinates is presented and used to simulate dispersive-scale Alfvén wave pulse propagation from the equator to the ionosphere along an L = 10 magnetic field line. The model is an extension of the hybrid MHD-kinetic electron model that incorporates ion Larmor radius corrections via the kinetic fluid model of Cheng and Johnson (1999). It is found that consideration of a realistic ion to electron temperature ratio decreases the propagation time of the wave from the plasma sheet to the ionosphere by several seconds relative to a ρi=0 case (which also implies shorter timing for a substorm onset signal) and leads to significant dispersion of wave energy perpendicular to the ambient magnetic field. Additionally, ion temperature effects reduce the parallel current and electron energization all along the field line for the same magnitude perpendicular electric field perturbation.

  13. Prediction of Significant Wave Heights in Extreme Storms Affecting Far North Alaska

    NASA Astrophysics Data System (ADS)

    Cassano, E. N.; Thornbrugh, C.; Lynch, A.

    2003-12-01

    Barrow, Alaska is located at the northernmost point of the United States on the shore of the Arctic Ocean. The area surrounding Barrow is low lying and is thus vulnerable to coastal flooding via waves and storm surges. Previous modeling of flooding resulting from a storm that affected Barrow and the rest of the North Slope coast region in October 1963 did not reproduce observed flooding, which was substantially greater than modeled. It is hypothesized that because this model only incorporated storm surge and not waves, the model was unable to simulate the total amount of flooding. The current study examines a recent storm that affected the North Slope of Alaska on July 28-30, 2003, and includes prediction of wave height using the SWAN (Simulating WAves Nearshore) model. In addition this study considers the formation and development, climatological context, and community responses for this storm. Results from the wave modeling portion of this study will be incorporated into a coastal flooding model in order to better simulate the coastal environment under extreme conditions in this area.

  14. Making and Propagating Elastic Waves: Overview of the new wave propagation code WPP

    SciTech Connect

    McCandless, K P; Petersson, N A; Nilsson, S; Rodgers, A; Sjogreen, B; Blair, S C

    2006-05-09

    We are developing a new parallel 3D wave propagation code at LLNL called WPP (Wave Propagation Program). WPP is being designed to incorporate the latest developments in embedded boundary and mesh refinement technology for finite difference methods, as well as having an efficient portable implementation to run on the latest supercomputers at LLNL. We are currently exploring seismic wave applications, including a recent effort to compute ground motions for the 1906 Great San Francisco Earthquake. This paper will briefly describe the wave propagation problem, features of our numerical method to model it, implementation of the wave propagation code, and results from the 1906 Great San Francisco Earthquake simulation.

  15. Incorporating Argumentation through Forensic Science

    ERIC Educational Resources Information Center

    Wheeler, Lindsay B.; Maeng, Jennifer L.; Smetana, Lara K.

    2014-01-01

    This article outlines how to incorporate argumentation into a forensic science unit using a mock trial. Practical details of the mock trial include: (1) a method of scaffolding students' development of their argument for the trial, (2) a clearly outlined set of expectations for students during the planning and implementation of the mock…

  16. Atmospheric Waves

    NASA Technical Reports Server (NTRS)

    2007-01-01

    With its Multispectral Visible Imaging Camera (MVIC), half of the Ralph instrument, New Horizons captured several pictures of mesoscale gravity waves in Jupiter's equatorial atmosphere. Buoyancy waves of this type are seen frequently on Earth - for example, they can be caused when air flows over a mountain and a regular cloud pattern forms downstream. In Jupiter's case there are no mountains, but if conditions in the atmosphere are just right, it is possible to form long trains of these small waves. The source of the wave excitation seems to lie deep in Jupiter's atmosphere, below the visible cloud layers at depths corresponding to pressures 10 times that at Earth's surface. The New Horizons measurements showed that the waves move about 100 meters per second faster than surrounding clouds; this is about 25% of the speed of sound on Earth and is much greater than current models of these waves predict. Scientists can 'read' the speed and patterns these waves to learn more about activity and stability in the atmospheric layers below.

  17. Moreton Waves

    NASA Technical Reports Server (NTRS)

    Thompson, B. J.

    1999-01-01

    "Moreton waves," named for the observer who popularized them, are a solar phenomenon also known in scientific literature as "Moreton-Ramsey wave," "flare waves," "flare-associated waves," "MHD blast waves," "chromospheric shock fronts" and various other combinations of terms which connote violently propagating impulsive disturbances. It is unclear whether all of the observations to which these terms have been applied pertain to a single physical phenomenon: there has perhaps been some overlap between the observations and the assumed physical properties of the observed occurrence. Moreton waves are ideally observed in the wings of H alpha, and appear as semi-circular fronts propagating at speeds ranging from several hundred to over a thousand km/sec. They form an arc, or "brow shape" which can span up to 180 degrees. Extrapolating the speed and locations of the arc indicates that the phenomenon's origin intersects well with the impulsive phase of the associated H alpha flare (if the flare exhibits an impulsive phase). However, the arc may not form or may not be observable until it is tens of megameters from the flaring region, and subsequently can propagate to distances exceeding 100 megameters. The high speeds and distances of propagation, plus the associated radio and energetic particle observations, provided strong evidence of a coronal, rather than a chromospheric origin. The H alpha manifestation of the wave is assumed to be the "ground track" or "skirt" of a three-dimensional disturbance.

  18. Multicomponent Body and Surface Wave Seismic Analysis using an Urban Land Streamer System: An Integrative Earthquake Hazards Assessment Approach

    NASA Astrophysics Data System (ADS)

    Gribler, G.; Liberty, L. M.

    2014-12-01

    We present earthquake site response results from a 48-channel multicomponent seismic land streamer and large weight drop system. We acquired data along a grid of city streets in western Idaho at a rate of a few km per day where we derived shear wave velocity profiles to a depth of 40-50 m by incorporating vertical and radial geophone signals to capture the complete elliptical Rayleigh wave motion. We also obtained robust p-wave reflection and refraction results by capturing the returned signals that arrive at non-vertical incidence angles that result from the high-velocity road surface layer. By integrating the derived shear wave velocity profiles with p-wave reflection results, we include depositional and tectonic boundaries from the upper few hundred meters into our analysis to help assess whether ground motions may be amplified by shallow bedrock. By including p-wave refraction information into the analysis, we can identify zones of high liquefaction potential by comparing shear wave and p-wave velocity (Vp/Vs) measurements relative to refraction-derived water table depths. The utilization of multicomponent land streamer data improves signal-noise levels over single component data with no additional field effort. The added multicomponent data processing step can be as simple as calculating the magnitude of the vector for surface wave and refraction arrivals or rotating the reflected signals to the maximum emergence angle based on near surface p-wave velocity information. We show example data from a number of Idaho communities where historical earthquakes have been recorded. We also present numerical models and systematic field tests that show the effects of a high velocity road surface layer in surface and body wave measurements. We conclude that multicomponent seismic information derived from seismic land streamers can provide a significant improvement in earthquake hazard assessment over a standard single component approach with only a small addition in

  19. Incorporation of copper into lysyl oxidase.

    PubMed

    Kosonen, T; Uriu-Hare, J Y; Clegg, M S; Keen, C L; Rucker, R B

    1997-10-01

    Lysyl oxidase is a copper-dependent enzyme involved in extracellular processing of collagens and elastin. Although it is known that copper is essential for the functional activity of the enzyme, there is little information on the incorporation of copper. In the present study we examined the insertion of copper into lysyl oxidase using 67Cu in cell-free transcription/translation assays and in normal skin fibroblast culture systems. When a full-length lysyl oxidase cDNA was used as a template for transcription/translation reactions in vitro, unprocessed prolysyl oxidase appeared to bind copper. To examine further the post-translational incorporation of copper into lysyl oxidase, confluent skin fibroblasts were incubated with inhibitors of protein synthesis (cycloheximide, 10 microg/ml), glycosylation (tunicamycin, 10 microg/ml), protein secretion (brefeldin A, 10 microg/ml) and prolysyl oxidase processing (procollagen C-peptidase inhibitor, 2.5 microg/ml) together with 300 microCi of carrier-free 67Cu. It was observed that protein synthesis was a prerequisite for copper incorporation, but inhibition of glycosylation by tunicamycin did not affect the secretion of 67Cu as lysyl oxidase. Brefeldin A inhibited the secretion of 67Ci-labelled lysyl oxidase by 46%, but the intracellular incorporation of copper into lysyl oxidase was not affected. In addition, the inhibition of the extracellular proteolytic processing of prolysyl oxidase to lysyl oxidase had minimal effects on the secretion of protein-bound 67Cu. Our results indicate that, similar to caeruloplasmin processing [Sato and Gitlin (1991) J. Biol. Chem. 266, 5128-5134], copper is inserted into prolysyl oxidase independently of glycosylation. PMID:9355764

  20. Delaying vortex breakdown by waves

    NASA Astrophysics Data System (ADS)

    Yao, M. F.; Jiang, L. B.; Wu, J. Z.; Ma, H. Y.; Pan, J. Y.

    1989-03-01

    The effect of spiral waves on delaying vortex breakdown in a tube is studied experimentally and theoretically. When a harmonic oscillation was imposed on one of guiding vanes in the tube, the breakdown was observed to be postponed appreciately. According to the generalized Lagrangian mean theory, proper forcing spiral waves may produce an additional streaming momentum, of which the effect is favorable and similar to an axial suction at downstream end. The delayed breakdown position is further predicted by using nonlinear wave theory. Qualitative agreement between theory and experiment is obtained, and experimental comparison of the effects due to forcing spiral wave and axial suction is made.

  1. Self-Consistent Model of Magnetospheric Electric Field, Ring Current, Plasmasphere, and Electromagnetic Ion Cyclotron Waves: Initial Results

    NASA Technical Reports Server (NTRS)

    Gamayunov, K. V.; Khazanov, G. V.; Liemohn, M. W.; Fok, M.-C.; Ridley, A. J.

    2009-01-01

    Further development of our self-consistent model of interacting ring current (RC) ions and electromagnetic ion cyclotron (EMIC) waves is presented. This model incorporates large scale magnetosphere-ionosphere coupling and treats self-consistently not only EMIC waves and RC ions, but also the magnetospheric electric field, RC, and plasmasphere. Initial simulations indicate that the region beyond geostationary orbit should be included in the simulation of the magnetosphere-ionosphere coupling. Additionally, a self-consistent description, based on first principles, of the ionospheric conductance is required. These initial simulations further show that in order to model the EMIC wave distribution and wave spectral properties accurately, the plasmasphere should also be simulated self-consistently, since its fine structure requires as much care as that of the RC. Finally, an effect of the finite time needed to reestablish a new potential pattern throughout the ionosphere and to communicate between the ionosphere and the equatorial magnetosphere cannot be ignored.

  2. Imploding conical shock waves

    NASA Astrophysics Data System (ADS)

    Paton, R. T.; Skews, B. W.; Rubidge, S.; Snow, J.

    2013-07-01

    The behaviour of conical shock waves imploding axisymmetrically was first studied numerically by Hornung (J Fluid Mech 409:1-12, 2000) and this prompted a limited experimental investigation into these complex flow patterns by Skews et al. (Shock Waves 11:323-326, 2002). Modification of the simulation boundary conditions, resulting in the loss of self-similarity, was necessary to image the flow experimentally. The current tests examine the temporal evolution of these flows utilising a converging conical gap of fixed width fed by a shock wave impinging at its entrance, supported by CFD simulations. The effects of gap thickness, angle and incident shock strength were investigated. The wave initially diffracts around the outer lip of the gap shedding a vortex which, for strong incident shock cases, can contain embedded shocks. The converging shock at exit reflects on the axis of symmetry with the reflected wave propagating outwards resulting in a triple point developing on the incident wave together with the associated shear layer. This axisymmetric shear layer rolls up into a mushroom-shaped toroidal vortex ring and forward-facing jet. For strong shocks, this deforms the Mach disk to the extent of forming a second triple point with the primary shock exhibiting a double bulge. Separate features resembling the Richtmeyer-Meshkov and Kelvin-Helmholtz instabilities were noted in some tests. Aside from the incident wave curvature, the reflection patterns demonstrated correspond well with the V- and DV-types identified by Hornung although type S was not clearly seen, possibly due to the occlusion of the reflection region by the outer diffraction vortex at these early times. Some additional computational work explicitly exploring the limits of the parameter space for such systems has demonstrated the existence of a possible further reflection type, called vN-type, which is similar to the von Neumann reflection for plane waves. It is recommended that the parameter space be

  3. Cincinnati Big Area Additive Manufacturing (BAAM)

    SciTech Connect

    Duty, Chad E.; Love, Lonnie J.

    2015-03-04

    Oak Ridge National Laboratory (ORNL) worked with Cincinnati Incorporated (CI) to demonstrate Big Area Additive Manufacturing which increases the speed of the additive manufacturing (AM) process by over 1000X, increases the size of parts by over 10X and shows a cost reduction of over 100X. ORNL worked with CI to transition the Big Area Additive Manufacturing (BAAM) technology from a proof-of-principle (TRL 2-3) demonstration to a prototype product stage (TRL 7-8).

  4. Scalar Gravitational Waves

    NASA Astrophysics Data System (ADS)

    Mottola, Emil

    2016-03-01

    General Relativity receives quantum corrections relevant at macroscopic distance scales and near event horizons. These arise from the conformal scalar degree of freedom in the extended effective field theory (EFT) of gravity generated by the trace anomaly of massless quantum fields in curved space. Linearized around flat space this quantum scalar degree of freedom combines with the conformal part of the metric and predicts the existence of scalar spin-0 ``breather'' propagating gravitational waves in addition to the transverse tensor spin-2 waves of classical General Relativity. Estimates of the expected strength of scalar gravitational radiation from compact astrophysical sources are given.

  5. Self-Incorporation of Coenzymes by Ribozymes

    NASA Technical Reports Server (NTRS)

    Breaker, Ronald R.; Joyce, Gerald F.

    1995-01-01

    RNA molecules that are assembled from the four standard nucleotides contain a limited number of chemical functional groups, a characteristic that is generally thought to restrict the potential for catalysis by ribozymes. Although polypeptides carry a wider range of functional groups, many contemporary protein-based enzymes employ coenzymes to augment their capabilities. The coenzymes possess additional chemical moieties that can participate directly in catalysis and thereby enhance catalytic function. In this work, we demonstrate a mechanism by which ribozymes can supplement their limited repertoire of functional groups through RNAcatalyzed incorporation of various coenzymes and coenzyme analogues. The group I ribozyme of Tetrahymena thermophila normally mediates a phosphoester transfer reaction that results in the covalent attachment of guanosine to the ribozyme. Here, a shortened version of the ribozyme is shown to catalyze the self-incorporation of coenzymes and coenzyme analogues, such as NAD+ and dephosphorylated CoA-SH. Similar ribozyme activities may have played an important role in the "RNA world," when RNA enzymes are thought to have maintained a complex metabolism in the absence of proteins and would have benefited from the inclusion of additional functional groups.

  6. Identifying Heat Waves in Florida: Considerations of Missing Weather Data

    PubMed Central

    Leary, Emily; Young, Linda J.; DuClos, Chris; Jordan, Melissa M.

    2015-01-01

    Background Using current climate models, regional-scale changes for Florida over the next 100 years are predicted to include warming over terrestrial areas and very likely increases in the number of high temperature extremes. No uniform definition of a heat wave exists. Most past research on heat waves has focused on evaluating the aftermath of known heat waves, with minimal consideration of missing exposure information. Objectives To identify and discuss methods of handling and imputing missing weather data and how those methods can affect identified periods of extreme heat in Florida. Methods In addition to ignoring missing data, temporal, spatial, and spatio-temporal models are described and utilized to impute missing historical weather data from 1973 to 2012 from 43 Florida weather monitors. Calculated thresholds are used to define periods of extreme heat across Florida. Results Modeling of missing data and imputing missing values can affect the identified periods of extreme heat, through the missing data itself or through the computed thresholds. The differences observed are related to the amount of missingness during June, July, and August, the warmest months of the warm season (April through September). Conclusions Missing data considerations are important when defining periods of extreme heat. Spatio-temporal methods are recommended for data imputation. A heat wave definition that incorporates information from all monitors is advised. PMID:26619198

  7. PlaneWave Admittance Method- a novel approach for determining the electromagnetic modes in photonic structures.

    PubMed

    Dems, Maciej; Kotynski, Rafal; Panajotov, Krassimir

    2005-05-01

    In this article we present a novel approach for determining the electromagnetic modes of photonic multilayer structures. We combine the plane wave expansion method with the method of lines resulting in a fast and accurate computational technique which we named the plane wave admittance method. In addition, we incorporate perfectly matched layers at the boundaries parallel to the multilayer surfaces which allow for easy determination of leaky modes. The convergence of the method is verified for the case of photonic crystal slab showing very good agreement with the results obtained with full three-dimensional plane wave expansion method while the numerical effort is largely reduced. The numerical implementation of the method will be soon available on the web.

  8. A global 3-D MHD model of the solar wind with Alfven waves

    NASA Technical Reports Server (NTRS)

    Usmanov, A. V.

    1995-01-01

    A fully three-dimensional solar wind model that incorporates momentum and heat addition from Alfven waves is developed. The proposed model upgrades the previous one by considering self-consistently the total system consisting of Alfven waves propagating outward from the Sun and the mean polytropic solar wind flow. The simulation region extends from the coronal base (1 R(sub s) out to beyond 1 AU. The fully 3-D MHD equations written in spherical coordinates are solved in the frame of reference corotating with the Sun. At the inner boundary, the photospheric magnetic field observations are taken as boundary condition and wave energy influx is prescribed to be proportional to the magnetic field strength. The results of the model application for several time intervals are presented.

  9. A two-scale approximation for wave-wave interactions in an operational wave model

    NASA Astrophysics Data System (ADS)

    Perrie, Will; Toulany, Bechara; Resio, Donald T.; Roland, Aron; Auclair, Jean-Pierre

    2013-10-01

    The two-scale approximation (hereafter, TSA) to the full Boltzman integral representation of quadruplet wave-wave interactions has recently been presented as a new method to estimate nonlinear transfer rates in wind waves, and has been tested for idealized spectral data, as well as for observed field measurements. TSA has been shown to perform well for wave spectra from field measurements, even for cases with directional energy shearing, compared to the Discrete Interaction Approximation (DIA), which is used in almost all operational wave forecast models. In this study, TSA is implemented in a modern operational wave model, WAVEWATCHIII®, hereafter WW3. Tests include idealized wave spectra based on field measurements, as well as additional tests for fetch-limited wave growth, and waves generated by hurricane Juan. Generally, TSA is shown to work well when its basic assumptions are met, when its first order, broad-scale term represents most of the spectrum, and its second order term is a perturbation-scale residual representing the rest of the spectrum. These conditions are easily met for test cases involving idealized JONSWAP-type spectra and in time-stepping cases when winds are spatially and temporally constant. To some extent, they also appear to be met in more demanding conditions, when storms move through their life cycles, with winds that change speed and direction, and with complex wave spectra, involving swell-windsea interactions, multiple peaks and directional shears.

  10. Uranium incorporation into amorphous silica.

    PubMed

    Massey, Michael S; Lezama-Pacheco, Juan S; Nelson, Joey M; Fendorf, Scott; Maher, Kate

    2014-01-01

    High concentrations of uranium are commonly observed in naturally occurring amorphous silica (including opal) deposits, suggesting that incorporation of U into amorphous silica may represent a natural attenuation mechanism and promising strategy for U remediation. However, the stability of uranium in opaline silicates, determined in part by the binding mechanism for U, is an important factor in its long-term fate. U may bind directly to the opaline silicate matrix, or to materials such as iron (hydr)oxides that are subsequently occluded within the opal. Here, we examine the coordination environment of U within opaline silica to elucidate incorporation mechanisms. Precipitates (with and without ferrihydrite inclusions) were synthesized from U-bearing sodium metasilicate solutions, buffered at pH ∼ 5.6. Natural and synthetic solids were analyzed with X-ray absorption spectroscopy and a suite of other techniques. In synthetic amorphous silica, U was coordinated by silicate in a double corner-sharing coordination geometry (Si at ∼ 3.8-3.9 Å) and a small amount of uranyl and silicate in a bidentate, mononuclear (edge-sharing) coordination (Si at ∼ 3.1-3.2 Å, U at ∼ 3.8-3.9 Å). In iron-bearing synthetic solids, U was adsorbed to iron (hydr)oxide, but the coordination environment also contained silicate in both edge-sharing and corner-sharing coordination. Uranium local coordination in synthetic solids is similar to that of natural U-bearing opals that retain U for millions of years. The stability and extent of U incorporation into opaline and amorphous silica represents a long-term repository for U that may provide an alternative strategy for remediation of U contamination. PMID:24984107

  11. A study of the non-linear response of the upper atmosphere to episodic and stochastic acoustic-gravity wave forcing

    NASA Astrophysics Data System (ADS)

    Lin, C. Y. T.; Deng, Y.; Sheng, C.; Drob, D. P.

    2015-12-01

    Waves of various spatial and temporal scales, including acoustic waves, gravity waves, tides, and planetary waves, modify the dynamics of the terrestrial atmosphere at all altitudes. Perturbations caused by the natural and mankind activities on the ground, such as volcano eruptions, earthquakes, explosions, propagate upward and impact the upper atmosphere. Among these waves, propagation of the atmospheric acoustic waves is particularly sensitive to the fine structure of the background atmosphere. However, the fine-structured gravity waves (smaller than 1° x 1°) are currently poorly measured especially at the altitudes above 100 km and are computationally too expensive for most models to incorporate properly. The Global Ionosphere Thermosphere Model (GITM) allows for non-hydrostatic solutions and has a flexible resolution. Thus, it is ideal for the study of vertical propagating waves. In this study, the ionospheric and thermospheric response to acoustic-gravity waves is first presented with an artificial source of various frequencies, followed by a case study of the 2014 Tohoku tsunami. Additionally a time-varying spectral gravity wavefield propagated from the ground is implemented into GITM to capture the statistical background structures that is crucial to the upper atmospheric models. Our results show the importance of consideration of background small-scale structures to interpretation of the observed ionospheric and thermospheric perturbations, such as traveling ionospheric disturbances (TIDs) and traveling atmospheric disturbances (TADs).

  12. Probabilistic seismic hazard estimates incorporating site effects - An example from Indiana, U.S.A

    USGS Publications Warehouse

    Hasse, J.S.; Park, C.H.; Nowack, R.L.; Hill, J.R.

    2010-01-01

    The U.S. Geological Survey (USGS) has published probabilistic earthquake hazard maps for the United States based on current knowledge of past earthquake activity and geological constraints on earthquake potential. These maps for the central and eastern United States assume standard site conditions with Swave velocities of 760 m/s in the top 30 m. For urban and infrastructure planning and long-term budgeting, the public is interested in similar probabilistic seismic hazard maps that take into account near-surface geological materials. We have implemented a probabilistic method for incorporating site effects into the USGS seismic hazard analysis that takes into account the first-order effects of the surface geologic conditions. The thicknesses of sediments, which play a large role in amplification, were derived from a P-wave refraction database with over 13, 000 profiles, and a preliminary geology-based velocity model was constructed from available information on S-wave velocities. An interesting feature of the preliminary hazard maps incorporating site effects is the approximate factor of two increases in the 1-Hz spectral acceleration with 2 percent probability of exceedance in 50 years for parts of the greater Indianapolis metropolitan region and surrounding parts of central Indiana. This effect is primarily due to the relatively thick sequence of sediments infilling ancient bedrock topography that has been deposited since the Pleistocene Epoch. As expected, the Late Pleistocene and Holocene depositional systems of the Wabash and Ohio Rivers produce additional amplification in the southwestern part of Indiana. Ground motions decrease, as would be expected, toward the bedrock units in south-central Indiana, where motions are significantly lower than the values on the USGS maps.

  13. Incorporating Spirituality in Primary Care.

    PubMed

    Isaac, Kathleen S; Hay, Jennifer L; Lubetkin, Erica I

    2016-06-01

    Addressing cultural competency in health care involves recognizing the diverse characteristics of the patient population and understanding how they impact patient care. Spirituality is an aspect of cultural identity that has become increasingly recognized for its potential to impact health behaviors and healthcare decision-making. We consider the complex relationship between spirituality and health, exploring the role of spirituality in primary care, and consider the inclusion of spirituality in existing models of health promotion. We discuss the feasibility of incorporating spirituality into clinical practice, offering suggestions for physicians. PMID:26832335

  14. Nonlinear interaction of dispersive Alfven waves and magnetosonic waves in space plasma

    SciTech Connect

    Sharma, R. P.; Kumar, Sanjay; Singh, H. D.

    2009-03-15

    This paper presents the model equations governing the nonlinear interaction between dispersive Alfven wave (DAW) and magnetosonic wave in the low-{beta} plasmas ({beta}<waves) applicable to solar corona and intermediate-{beta} plasmas (m{sub e}/m{sub i}<<{beta}<<1; known as kinetic Alfven waves) applicable to solar wind in Earth's magnetosphere. When the ponderomotive nonlinearities are incorporated in the DAW dynamics, the model equations of DAW and magnetosonic wave turn out to be a modified Zakharov system of equations. Numerical solution of the problem has been obtained when the incident pump kinetic Alfven wave/inertial Alfven wave is having a small perturbation.

  15. Np Incorporation into Uranyl Alteration Phases: A Quantum Mechanical Approach

    SciTech Connect

    Shuller, Lindsay; Ewing, Rodney C. |; Becker, Udo

    2007-07-01

    Neptunium is a major contributor to the long-term radioactivity in a geologic repository for spent nuclear fuel (SNF) due to its long half-life (2.1 million years). The mobility of Np may be decreased by its incorporation into the U{sup 6+} phases that form during the corrosion of SNF. The ionic radii of Np{sup 5+} (0.089 nm) and U{sup 6+} (0.087 nm) are similar, as is their chemistry. Experimental studies have shown that Np can be incorporated into uranyl phases up to concentrations on the order of 100 ppm. The low concentration of Np in the uranyl phases complicates experimental detection and presents a significant challenge for determining the incorporation mechanism. Therefore, we have used quantum mechanical calculations to investigate incorporation mechanisms and evaluate the energetics of Np substituting for U. CASTEP, a density functional theory based code that uses plane waves to model the behavior of the valence electrons and pseudo-potentials to model the behavior of the core and inner valence electrons, was used to calculate optimal H positions, relaxed geometry, and the energy of different uranyl phases. The incorporation energy for Np into uranyl alteration phases was calculated for studtite, [(UO{sub 2})O{sub 2}(H{sub 2}O){sub 2}](H{sub 2}O){sub 2}, and boltwoodite, HK(UO{sub 2})(SiO{sub 4}) 1.5(H{sub 2}O). Studtite is the rare case of a stable, naturally-occurring peroxide mineral, in this case a uranyl hydroxyl peroxide that forms in the presence of H{sub 2}O{sub 2} from the radiolysis of H{sub 2}O. For studtite, two incorporation mechanisms were evaluated: (1) charge-balanced substitution of Np{sup 5+} and H{sup +} for one U{sup 6+}, and (2) direct substitution of Np{sup 6+} for U{sup 6+}. For boltwoodite, the H atomic positions prior to Np incorporation were determined, as well as the Np incorporation mechanisms and the corresponding substitution energies. The preferential incorporation of Np into different structure types of U{sup 6+} minerals

  16. On the use of wave parameterizations and a storm impact scaling model in National Weather Service Coastal Flood and decision support operations

    USGS Publications Warehouse

    Mignone, Anthony; Stockdon, H.; Willis, M.; Cannon, J.W.; Thompson, R.

    2012-01-01

    National Weather Service (NWS) Weather Forecast Offices (WFO) are responsible for issuing coastal flood watches, warnings, advisories, and local statements to alert decision makers and the general public when rising water levels may lead to coastal impacts such as inundation, erosion, and wave battery. Both extratropical and tropical cyclones can generate the prerequisite rise in water level to set the stage for a coastal impact event. Forecasters use a variety of tools including computer model guidance and local studies to help predict the potential severity of coastal flooding. However, a key missing component has been the incorporation of the effects of waves in the prediction of total water level and the associated coastal impacts. Several recent studies have demonstrated the importance of incorporating wave action into the NWS coastal flood program. To follow up on these studies, this paper looks at the potential of applying recently developed empirical parameterizations of wave setup, swash, and runup to the NWS forecast process. Additionally, the wave parameterizations are incorporated into a storm impact scaling model that compares extreme water levels to beach elevation data to determine the mode of coastal change at predetermined “hotspots” of interest. Specifically, the storm impact model compares the approximate storm-induced still water level, which includes contributions from tides, storm surge, and wave setup, to dune crest elevation to determine inundation potential. The model also compares the combined effects of tides, storm surge, and the 2 % exceedance level for vertical wave runup (including both wave setup and swash) to dune toe and crest elevations to determine if erosion and/or ocean overwash may occur. The wave parameterizations and storm impact model are applied to two cases in 2009 that led to significant coastal impacts and unique forecast challenges in North Carolina: the extratropical “Nor'Ida” event during 11-14 November and

  17. Efficient way to convert propagating waves into guided waves via gradient wire structures.

    PubMed

    Chu, Hong Chen; Luo, Jie; Lai, Yun

    2016-08-01

    We propose a method for the design of gradient wire structures that are capable of converting propagating waves into guided waves along the wire. The conversion process is achieved by imposing an additional wave vector to the scattered waves via the gradient wire structure, such that the wave vector of scattered waves is beyond the wave number in the background medium. Thus, the scattered waves turn into evanescent waves. We demonstrate that two types of gradient wire structures, with either a gradient permittivity and a fixed radius, or a gradient radius and a fixed permittivity, can both be designed to realize such a wave conversion effect. The principle demonstrated in our work has potential applications in various areas including nanophotonics, silicone photonics, and plasmonics.

  18. Efficient way to convert propagating waves into guided waves via gradient wire structures.

    PubMed

    Chu, Hong Chen; Luo, Jie; Lai, Yun

    2016-08-01

    We propose a method for the design of gradient wire structures that are capable of converting propagating waves into guided waves along the wire. The conversion process is achieved by imposing an additional wave vector to the scattered waves via the gradient wire structure, such that the wave vector of scattered waves is beyond the wave number in the background medium. Thus, the scattered waves turn into evanescent waves. We demonstrate that two types of gradient wire structures, with either a gradient permittivity and a fixed radius, or a gradient radius and a fixed permittivity, can both be designed to realize such a wave conversion effect. The principle demonstrated in our work has potential applications in various areas including nanophotonics, silicone photonics, and plasmonics. PMID:27472616

  19. Surface acoustic wave stabilized oscillators: Additional aging results

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Updated aging data for SAW oscillators with aluminum transducers on ST-cut quartz, for gold transducers on ST-cut quartz, and for aluminum transducers on SiO2/LiTaO3. Devices with gold transducers age differently (both and shape of curve) from those having a aluminum transducers indicating the transducer metallization can represent an important aging mechanism.

  20. Vector plane wave spectrum of an arbitrary polarized electromagnetic wave.

    PubMed

    Guo, Hanming; Chen, Jiabi; Zhuang, Songlin

    2006-03-20

    By using the method of modal expansions of the independent transverse fields, a formula of vector plane wave spectrum (VPWS) of an arbitrary polarized electromagnetic wave in a homogenous medium is derived. In this formula VPWS is composed of TM- and TE-mode plane wave spectrum, where the amplitude and unit polarized direction of every plane wave are separable, which has more obviously physical meaning and is more convenient to apply in some cases compared to previous formula of VPWS. As an example, the formula of VPWS is applied to the well-known radially and azimuthally polarized beam. In addition, vector Fourier-Bessel transform pairs of an arbitrary polarized electromagnetic wave with circular symmetry are also derived.

  1. Vector plane wave spectrum of an arbitrary polarized electromagnetic wave

    NASA Astrophysics Data System (ADS)

    Guo, Hanming; Chen, Jiabi; Zhuang, Songlin

    2006-03-01

    By using the method of modal expansions of the independent transverse fields, a formula of vector plane wave spectrum (VPWS) of an arbitrary polarized electromagnetic wave in a homogenous medium is derived. In this formula VPWS is composed of TM- and TE-mode plane wave spectrum, where the amplitude and unit polarized direction of every plane wave are separable, which has more obviously physical meaning and is more convenient to apply in some cases compared to previous formula of VPWS. As an example, the formula of VPWS is applied to the well-known radially and azimuthally polarized beam. In addition, vector Fourier-Bessel transform pairs of an arbitrary polarized electromagnetic wave with circular symmetry are also derived.

  2. Optoelectronic devices incorporating fluoropolymer compositions for protection

    SciTech Connect

    Chen, Xuming; Chum, Pak-Wing S.; Howard, Kevin E.; Lopez, Leonardo C.; Sumner, William C.; Wu, Shaofu

    2015-12-22

    The fluoropolymer compositions of the present invention generally incorporate ingredients comprising one or more fluoropolymers, an ultraviolet light protection component (hereinafter UV protection component), and optionally one or more additional ingredients if desired. The UV protection component includes a combination of at least one hindered tertiary amine (HTA) compound having a certain structure and a weight average molecular weight of at least 1000. This tertiary amine is used in combination with at least one organic, UV light absorbing compound (UVLA compound) having a weight average molecular weight greater than 500. When the HTA compound and the UVLA compound are selected according to principles of the present invention, the UV protection component provides fluoropolymer compositions with significantly improved weatherability characteristics for protecting underlying materials, features, structures, components, and/or the like. In particular, fluoropolymer compositions incorporating the UV protection component of the present invention have unexpectedly improved ability to resist blackening, coloration, or other de gradation that may be caused by UV exposure. As a consequence, devices protected by these compositions would be expected to have dramatically improved service life. The compositions have a wide range of uses but are particularly useful for forming protective layers in optoelectronic devices.

  3. Incorporating Geospatial Technology into Teacher Professional Development

    NASA Astrophysics Data System (ADS)

    Sproles, E. A.; Songer, L.

    2009-12-01

    The need for students to think spatially and use geospatial technologies is becoming more critical as these tools and concepts are increasingly incorporated into a broad range of occupations and academic disciplines. Geospatial Teaching Across the Curriculum (Geo-STAC) is a collaborative program that provides high school teachers with mentored professional development workshops in geospatial thought and technology. The seminars, led by community college faculty, give high school teachers the ability to incorporate geospatial technology into coursework across the curriculum — in Science, Technology, Engineering, and Math (STEM) and non-STEM disciplines. Students participating in the hands-on lessons gain experience in web-based and desktop Geographic Information Systems (GIS). The goals of the workshop are for teachers to: (1) understand the importance of geospatial thinking; (2) learn how to employ geospatial thinking in each discipline; (3) learn about geospatial technologies; (4) develop a Web-based GIS lesson; and, (5) implement a Web-based GIS lesson. Additionally, Geo-STAC works with high school students so that they: (1) understand the importance of geospatial technologies and careers in future job markets; (2) learn how to use Web-based GIS to solve problems; and, (3) visit the community college GIS lab and experience using desktop GIS. Geo-STAC actively disseminates this collaborative model to colleges to community colleges and high schools across the country.

  4. Incorporation of UK Met Office's radiation scheme into CPTEC's global model

    NASA Astrophysics Data System (ADS)

    Chagas, Júlio C. S.; Barbosa, Henrique M. J.

    2009-03-01

    Current parameterization of radiation in the CPTEC's (Center for Weather Forecast and Climate Studies, Cachoeira Paulista, SP, Brazil) operational AGCM has its origins in the work of Harshvardhan et al. (1987) and uses the formulation of Ramaswamy and Freidenreich (1992) for the short-wave absorption by water vapor. The UK Met Office's radiation code (Edwards and Slingo, 1996) was incorporated into CPTEC's global model, initially for short-wave only, and some impacts of that were shown by Chagas and Barbosa (2006). Current paper presents some impacts of the complete incorporation (both short-wave and long-wave) of UK Met Office's scheme. Selected results from off-line comparisons with line-by-line benchmark calculations are shown. Impacts on the AGCM's climate are assessed by comparing output of climate runs of current and modified AGCM with products from GEWEX/SRB (Surface Radiation Budget) project.

  5. Fracture imaging with converted elastic waves

    SciTech Connect

    Nihei, K.T.; Nakagawa, S.; Myer, L.R.

    2001-05-29

    This paper examines the seismic signatures of discrete, finite-length fractures, and outlines an approach for elastic, prestack reverse-time imaging of discrete fractures. The results of this study highlight the importance of incorporating fracture-generated P-S converted waves into the imaging method, and presents an alternate imaging condition that can be used in elastic reverse-time imaging when a direct wave is recorded (e.g., for crosswell and VSP acquisition geometries).

  6. Determining wave direction using curvature parameters.

    PubMed

    de Queiroz, Eduardo Vitarelli; de Carvalho, João Luiz Baptista

    2016-01-01

    The curvature of the sea wave was tested as a parameter for estimating wave direction in the search for better results in estimates of wave direction in shallow waters, where waves of different sizes, frequencies and directions intersect and it is difficult to characterize. We used numerical simulations of the sea surface to determine wave direction calculated from the curvature of the waves. Using 1000 numerical simulations, the statistical variability of the wave direction was determined. The results showed good performance by the curvature parameter for estimating wave direction. Accuracy in the estimates was improved by including wave slope parameters in addition to curvature. The results indicate that the curvature is a promising technique to estimate wave directions.•In this study, the accuracy and precision of curvature parameters to measure wave direction are analyzed using a model simulation that generates 1000 wave records with directional resolution.•The model allows the simultaneous simulation of time-series wave properties such as sea surface elevation, slope and curvature and they were used to analyze the variability of estimated directions.•The simultaneous acquisition of slope and curvature parameters can contribute to estimates wave direction, thus increasing accuracy and precision of results. PMID:27408830

  7. Freak waves: is prediction possible?

    NASA Astrophysics Data System (ADS)

    Toffoli, A.; Lefevre, J. M.; Lehner, S.; Monbaliu, J.

    2003-04-01

    Freak waves are individual waves of exceptional height or steepness and more and more they are believed to have caused a large number of casualties to ships and offshore structures. Theoretical and experimental studies have demonstrated their existence and a number of them have been objectively recorded in situ. Ships that founder represent a great disaster both from an economical and a human point of view. Moreover the environmental collateral damages may be enormous. Therefore description of freak waves is not only important for design work but also for operational purposes it would be of great benefit if a warning might be given to mariners. Meteo-centers already add wave forecasts in the weather and sea bulletins, usually in terms of significant wave height, wave period and wave direction both for wind sea and swell conditions. These forecasts are based on spectral wave models. Although a spectrum only gives some average description of the sea-state, and therefore no details about the instantaneous position of the sea surface, it might contain additional information that points at an increased risk for the occurrence of exceptional waves. It is one of the objectives of the EU project MaxWave to investigate this. To this end a database with 650 ship accidents was extracted from the Lloyd’s Marine Information Service (LMIS) and Lloyd’s casualty reports. The database covers serious casualties, including total losses, reported to all propelled sea-going merchant ships in the world of about 100 gross tonnage and above, due to bad weather. For these accidents, wave and wind conditions were downloaded from the ECMWF-archive. The wave information included full spectra allowing to calculate additional parameters from the spectra such as the wave steepness, bandwidth, and directional spread. The correlation between casualties and sea-state may help in identifying situations of increased risk, next to ocean areas more prone to bad weather in general and abnormal waves

  8. Radiation Shielding Materials and Containers Incorporating Same

    DOEpatents

    Mirsky, Steven M.; Krill, Stephen J.; and Murray, Alexander P.

    2005-11-01

    An improved radiation shielding material and storage systems for radioactive materials incorporating the same. The PYRolytic Uranium Compound (''PYRUC'') shielding material is preferably formed by heat and/or pressure treatment of a precursor material comprising microspheres of a uranium compound, such as uranium dioxide or uranium carbide, and a suitable binder. The PYRUC shielding material provides improved radiation shielding, thermal characteristic, cost and ease of use in comparison with other shielding materials. The shielding material can be used to form containment systems, container vessels, shielding structures, and containment storage areas, all of which can be used to house radioactive waste. The preferred shielding system is in the form of a container for storage, transportation, and disposal of radioactive waste. In addition, improved methods for preparing uranium dioxide and uranium carbide microspheres for use in the radiation shielding materials are also provided.

  9. Radiation shielding materials and containers incorporating same

    DOEpatents

    Mirsky, Steven M.; Krill, Stephen J.; Murray, Alexander P.

    2005-11-01

    An improved radiation shielding material and storage systems for radioactive materials incorporating the same. The PYRolytic Uranium Compound ("PYRUC") shielding material is preferably formed by heat and/or pressure treatment of a precursor material comprising microspheres of a uranium compound, such as uranium dioxide or uranium carbide, and a suitable binder. The PYRUC shielding material provides improved radiation shielding, thermal characteristic, cost and ease of use in comparison with other shielding materials. The shielding material can be used to form containment systems, container vessels, shielding structures, and containment storage areas, all of which can be used to house radioactive waste. The preferred shielding system is in the form of a container for storage, transportation, and disposal of radioactive waste. In addition, improved methods for preparing uranium dioxide and uranium carbide microspheres for use in the radiation shielding materials are also provided.

  10. Electrostatic waves in the magnetosphere.

    NASA Technical Reports Server (NTRS)

    Scarf, F. L.; Fredricks, R. W.

    1972-01-01

    Electric dipole antennas on magnetospheric spacecraft measure E field components of many kinds of electromagnetic waves. In addition, lower hybrid resonance emissions are frequently observed well above the ionosphere. The Ogo 5 plasma wave experiment has also detected new forms of electrostatic emissions that appear to interact very strongly with the local plasma particles. Greatly enhanced wave amplitudes have been found during the expansion phases of substorms, and analysis indicates that these emissions produce strong pitch angle diffusion. Intense broadband electrostatic turbulence is also detected at current layers containing steep magnetic field gradients. This current-driven instability is operative at the bow shock and also at field null regions just within the magnetosheath, and at the magnetopause near the dayside polar cusp. The plasma turbulence appears to involve ion acoustic waves, and the wave particle scattering provides an important collisionless dissipation mechanism for field merging.

  11. Kemp Echo Lattices Incorporating Hair Cell Nonlinearities

    NASA Astrophysics Data System (ADS)

    Sellami, Louiza

    In this thesis we develop a two-part model of the inner ear that can be used to simulate Kemp echoes, in their impulse response, and from which a characterization of the cochlea can be made. To accomplish this task, in the first part, we propose a linear digital scattering model of the cochlea, based on the well known unidimensional transmission line model into which we incorporate nonuniform and loss properties. The lattice structure of the digital scattering model is obtained by rephrasing the model equations in terms of incident and reflected waves. A spectral estimation method, which treats the system as an ARMA filter with a minimum phase transfer function of unknown degree, is used to estimate the transfer function of the cochlea. This method utilizes the theory of positive real and bounded real functions and Richard's theorem on the concept of degree reduction to determine both the degree and the predictor coefficients of the filter. The scattering model is then realized, using a new synthesis technique, from the overall transfer function and the zeros of transmission, as a cascade of real lossless lattice filters of degree two, closed on a load section. To change the nature of the sections from lossless to lossy, a new method, based on the properties of the proposed lattice structure and the damping parameter of the cochlea, was developed to distribute the load factor among the sections. Each lattice filter is described by a transfer scattering matrix whose entries are functions of the mechanical and geometrical parameters of the cochlea. The proposed synthesis method leads to a systematic estimation of the parameters of the cochlea. In the second part, we introduce a nonlinear bidirectional mechano-electrical model of a hair cell, estimate its components from experimental data, analyze its behavior, simulate it, and compare the results with experimental findings. We than propose a schematic procedure to realize a nonlinear model of the cochlea by

  12. Principle of least wave change.

    PubMed

    Abramson, N

    1989-05-01

    Fermat's principle of least time has some well-known limitations. It does not, for example, apply to diffraction gratings and holograms, because it does not include the concept of waves. The substitution of least number of waves in flight for least time of flight and the addition of a term that is a function of the grating frequency result in a generalized principle. It is easy to remember because it is based on only the number of waves minus the number of grooves, and it would be especially useful when refraction and diffraction are combined, as, for example, in some holographic optical elements. PMID:2723846

  13. Direct Drive Wave Energy Buoy

    SciTech Connect

    Rhinefrank, Kenneth E.; Lenee-Bluhm, Pukha; Prudell, Joseph H.; Schacher, Alphonse A.; Hammagren, Erik J.; Zhang, Zhe

    2013-07-29

    The most prudent path to a full-scale design, build and deployment of a wave energy conversion (WEC) system involves establishment of validated numerical models using physical experiments in a methodical scaling program. This Project provides essential additional rounds of wave tank testing at 1:33 scale and ocean/bay testing at a 1:7 scale, necessary to validate numerical modeling that is essential to a utility-scale WEC design and associated certification.

  14. A maximally informative version of inelastic scattering of electromagnetic waves by Langmuir waves

    SciTech Connect

    Erofeev, V. I.

    2015-09-15

    The concept of informativeness of nonlinear plasma physics scenarios is explained. Natural ideas of developing highly informative models of plasma kinetics are spelled out. A maximally informative version of inelastic scattering of electromagnetic waves by Langmuir waves in a weakly turbulent inhomogeneous plasma is developed with consideration of possible changes in wave polarization. In addition, a new formula for wave drift in spatial positions and wave vectors is derived. New scenarios of the respective wave drift and inelastic scattering are compared with the previous visions. The results indicate the need for further revision of the traditional understanding of nonlinear plasma phenomena.

  15. 49 CFR 195.3 - Incorporation by reference.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 CFR for a listing of the earlier editions. (b) All incorporated materials are available for... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. In addition... Fittings Industry, Inc. (MSS), 127 Park Street, NE., Vienna, VA 22180. 5. American Society for Testing...

  16. 49 CFR 195.3 - Incorporation by reference.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 CFR for a listing of the earlier editions. (b) All incorporated materials are available for... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. In addition... Fittings Industry, Inc. (MSS), 127 Park Street, NE., Vienna, VA 22180. 5. American Society for Testing...

  17. 49 CFR 195.3 - Incorporation by reference.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 CFR for a listing of the earlier editions. (b) All incorporated materials are available for... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. In addition... Fittings Industry, Inc. (MSS), 127 Park Street, NE., Vienna, VA 22180. 5. American Society for Testing...

  18. Incorporating Microcomputers into Secretarial and Clerical Vocational Programs. Final Report.

    ERIC Educational Resources Information Center

    Buck, Judy; Jackson, Gloria

    A project was undertaken to review and restructure the secretarial and clerical curriculum at Sikeston Area Vocational School in Sikeston, Missouri. Input from advisory committee members, members of the business community, teachers, and published articles were synthesized to identify additional units that needed to be incorporated into the…

  19. 49 CFR 195.3 - Incorporation by reference.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 CFR for a listing of the earlier editions. (b) All incorporated materials are available for... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. In addition...: Source and name of referenced material 49 CFR reference A. Pipeline Research Council International,...

  20. On neutron surface waves

    SciTech Connect

    Ignatovich, V. K.

    2009-01-15

    It is shown that neutron surface waves do not exist. The difference between the neutron wave mechanics and the wave physics of electromagnetic and acoustic processes, which allows the existence of surface waves, is analyzed.

  1. Relativistic spherical plasma waves

    NASA Astrophysics Data System (ADS)

    Bulanov, S. S.; Maksimchuk, A.; Schroeder, C. B.; Zhidkov, A. G.; Esarey, E.; Leemans, W. P.

    2012-02-01

    Tightly focused laser pulses that diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we study theoretically and numerically relativistic spherical wake waves and their properties, including wave breaking.

  2. Wave Turbulence

    NASA Astrophysics Data System (ADS)

    Newell, Alan C.; Rumpf, Benno

    2011-01-01

    In this article, we state and review the premises on which a successful asymptotic closure of the moment equations of wave turbulence is based, describe how and why this closure obtains, and examine the nature of solutions of the kinetic equation. We discuss obstacles that limit the theory's validity and suggest how the theory might then be modified. We also compare the experimental evidence with the theory's predictions in a range of applications. Finally, and most importantly, we suggest open challenges and encourage the reader to apply and explore wave turbulence with confidence. The narrative is terse but, we hope, delivered at a speed more akin to the crisp pace of a Hemingway story than the wordjumblingtumbling rate of a Joycean novel.

  3. Twisting Neutron Waves

    NASA Astrophysics Data System (ADS)

    Pushin, Dmitry

    Most waves encountered in nature can be given a ``twist'', so that their phase winds around an axis parallel to the direction of wave propagation. Such waves are said to possess orbital angular momentum (OAM). For quantum particles such as photons, atoms, and electrons, this corresponds to the particle wavefunction having angular momentum of Lℏ along its propagation axis. Controlled generation and detection of OAM states of photons began in the 1990s, sparking considerable interest in applications of OAM in light and matter waves. OAM states of photons have found diverse applications such as broadband data multiplexing, massive quantum entanglement, optical trapping, microscopy, quantum state determination and teleportation, and interferometry. OAM states of electron beams have been used to rotate nanoparticles, determine the chirality of crystals and for magnetic microscopy. Here I discuss the first demonstration of OAM control of neutrons. Using neutron interferometry with a spatially incoherent input beam, we show the addition and conservation of quantum angular momenta, entanglement between quantum path and OAM degrees of freedom. Neutron-based quantum information science heretofore limited to spin, path, and energy degrees of freedom, now has access to another quantized variable, and OAM modalities of light, x-ray, and electron beams are extended to a massive, penetrating neutral particle. The methods of neutron phase imprinting demonstrated here expand the toolbox available for development of phase-sensitive techniques of neutron imaging. Financial support provided by the NSERC Create and Discovery programs, CERC and the NIST Quantum Information Program is acknowledged.

  4. Numeral Incorporation in Japanese Sign Language

    ERIC Educational Resources Information Center

    Ktejik, Mish

    2013-01-01

    This article explores the morphological process of numeral incorporation in Japanese Sign Language. Numeral incorporation is defined and the available research on numeral incorporation in signed language is discussed. The numeral signs in Japanese Sign Language are then introduced and followed by an explanation of the numeral morphemes which are…

  5. 49 CFR 572.190 - Incorporated materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Register approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.190 Section 572.190... Dummy, Small Adult Female § 572.190 Incorporated materials. (a) The following materials are...

  6. 49 CFR 572.30 - Incorporated materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.30 Section 572.30....30 Incorporated materials. (a) The drawings and specifications referred to in this regulation that... Federal Register has approved the materials incorporated by reference. For materials subject to...

  7. 49 CFR 587.5 - Incorporated materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 587.5 Section 587.5... Barrier § 587.5 Incorporated materials. (a) The drawings and specifications referred to in this regulation that are not set forth in full are hereby incorporated in this part by reference. These materials...

  8. 49 CFR 572.30 - Incorporated materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Incorporated materials. 572.30 Section 572.30....30 Incorporated materials. (a) The drawings and specifications referred to in this regulation that... Federal Register has approved the materials incorporated by reference. For materials subject to...

  9. 49 CFR 572.30 - Incorporated materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Incorporated materials. 572.30 Section 572.30....30 Incorporated materials. (a) The drawings and specifications referred to in this regulation that... Federal Register has approved the materials incorporated by reference. For materials subject to...

  10. 49 CFR 572.190 - Incorporated materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Register approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part... 49 Transportation 7 2014-10-01 2014-10-01 false Incorporated materials. 572.190 Section 572.190... Test Dummy, Small Adult Female § 572.190 Incorporated materials. (a) The following materials are...

  11. 49 CFR 587.5 - Incorporated materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Incorporated materials. 587.5 Section 587.5... Barrier § 587.5 Incorporated materials. (a) The drawings and specifications referred to in this regulation that are not set forth in full are hereby incorporated in this part by reference. These materials...

  12. 49 CFR 587.5 - Incorporated materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Incorporated materials. 587.5 Section 587.5... Barrier § 587.5 Incorporated materials. (a) The drawings and specifications referred to in this regulation that are not set forth in full are hereby incorporated in this part by reference. These materials...

  13. 49 CFR 587.5 - Incorporated materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Incorporated materials. 587.5 Section 587.5... Barrier § 587.5 Incorporated materials. (a) The drawings and specifications referred to in this regulation that are not set forth in full are hereby incorporated in this part by reference. These materials...

  14. 49 CFR 572.190 - Incorporated materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Register approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part... 49 Transportation 7 2011-10-01 2011-10-01 false Incorporated materials. 572.190 Section 572.190... Dummy, Small Adult Female § 572.190 Incorporated materials. (a) The following materials are...

  15. 49 CFR 572.190 - Incorporated materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Register approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part... 49 Transportation 7 2012-10-01 2012-10-01 false Incorporated materials. 572.190 Section 572.190... Dummy, Small Adult Female § 572.190 Incorporated materials. (a) The following materials are...

  16. 49 CFR 572.30 - Incorporated materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Incorporated materials. 572.30 Section 572.30....30 Incorporated materials. (a) The drawings and specifications referred to in this regulation that... Federal Register has approved the materials incorporated by reference. For materials subject to...

  17. 49 CFR 572.190 - Incorporated materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Register approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part... 49 Transportation 7 2013-10-01 2013-10-01 false Incorporated materials. 572.190 Section 572.190... Test Dummy, Small Adult Female § 572.190 Incorporated materials. (a) The following materials are...

  18. 49 CFR 572.30 - Incorporated materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Incorporated materials. 572.30 Section 572.30....30 Incorporated materials. (a) The drawings and specifications referred to in this regulation that... Federal Register has approved the materials incorporated by reference. For materials subject to...

  19. 49 CFR 587.5 - Incorporated materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Incorporated materials. 587.5 Section 587.5... Barrier § 587.5 Incorporated materials. (a) The drawings and specifications referred to in this regulation that are not set forth in full are hereby incorporated in this part by reference. These materials...

  20. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects.

  1. Spin effect on parametric interactions of waves in magnetoplasmas

    SciTech Connect

    Shahid, M.; Melrose, D. B.; Jamil, M.; Murtaza, G.

    2012-11-15

    The parametric decay instability of upper hybrid wave into low-frequency electromagnetic Shear Alfven wave and Ordinary mode radiation (O-mode) has been investigated in an electron-ion plasma immersed in the uniform external magnetic field. Incorporating quantum effect due to electron spin, the fluid model has been used to investigate the linear and nonlinear response of the plasma species for three-wave coupling in a magnetoplasma. It is shown that the spin of electrons has considerable effect on the parametric decay of upper hybrid wave into Ordinary mode radiation (O-mode) and Shear Alfven wave even in classical regime.

  2. Face Recognition Incorporating Ancillary Information

    NASA Astrophysics Data System (ADS)

    Kim, Sang-Ki; Toh, Kar-Ann; Lee, Sangyoun

    2007-12-01

    Due to vast variations of extrinsic and intrinsic imaging conditions, face recognition remained to be a challenging computer vision problem even today. This is particularly true when the passive imaging approach is considered for robust applications. To advance existing recognition systems for face, numerous techniques and methods have been proposed to overcome the almost inevitable performance degradation due to external factors such as pose, expression, occlusion, and illumination. In particular, the recent part-based method has provided noticeable room for verification performance improvement based on the localized features which have good tolerance to variation of external conditions. The part-based method, however, does not really stretch the performance without incorporation of global information from the holistic method. In view of the need to fuse the local information and the global information in an adaptive manner for reliable recognition, in this paper we investigate whether such external factors can be explicitly estimated and be used to boost the verification performance during fusion of the holistic and part-based methods. Our empirical evaluations show noticeable performance improvement adopting the proposed method.

  3. MHD Waves in the Solar Wind

    NASA Astrophysics Data System (ADS)

    Ofman, L.

    2016-02-01

    This chapter focuses on reviewing several observational aspects of magnetohydrodynamic (MHD) waves in the solar wind, in particular on Alfvén waves, Alfvénic turbulent spectrum, and their role in heating and accelerating the solar wind. It also reviews computational models that incorporate Alfvén waves as the driving source of the wind in the lower corona (coronal holes) and in the inner heliosphere, with emphasis on multi-dimensional models. Evidence for MHD waves in the solar wind is obtained from interplanetary scintillation (IPS) observations using Earth-based radio telescope observations of distant (galactic) radio sources. The solar wind electron density variability in the line of sight affects the received radio signal. The propagating fluctuations and their correlations are used to estimate the solar wind velocity and the wave amplitude in the parallel and the perpendicular directions in line of sight.

  4. Stability of steady rotational water-waves of finite amplitude on arbitrary shear currents

    NASA Astrophysics Data System (ADS)

    Seez, William; Abid, Malek; Kharif, Christian

    2016-04-01

    A versatile solver for the two-dimensional Euler equations with an unknown free-surface has been developed. This code offers the possibility to calculate two-dimensional, steady rotational water-waves of finite amplitude on an arbitrary shear current. Written in PYTHON the code incorporates both pseudo-spectral and finite-difference methods in the discretisation of the equations and thus allows the user to capture waves with large steepnesses. As such it has been possible to establish that, in a counter-flowing situation, the existence of wave solutions is not guaranteed and depends on a pair of parameters representing mass flux and vorticity. This result was predicted, for linear solutions, by Constantin. Furthermore, experimental comparisons, both with and without vorticity, have proven the precision of this code. Finally, waves propagating on top of highly realistic shear currents (exponential profiles under the surface) have been calculated following current profiles such as those used by Nwogu. In addition, a stability analysis routine has been developed to study the stability regimes of base waves calculated with the two-dimensional code. This linear stability analysis is based on three dimensional perturbations of the steady situation which lead to a generalised eigenvalue problem. Common instabilities of the first and second class have been detected, while a third class of wave-instability appears due to the presence of strong vorticity. {1} Adrian Constantin and Walter Strauss. {Exact steady periodic water waves with vorticity}. Communications on Pure and Applied Mathematics, 57(4):481-527, April 2004. Okey G. Nwogu. {Interaction of finite-amplitude waves with vertically sheared current fields}. Journal of Fluid Mechanics, 627:179, May 2009.

  5. Incorporating Yoga into College Counseling

    ERIC Educational Resources Information Center

    Adams, Christopher M.; Puig, Ana

    2008-01-01

    Yoga has become increasingly popular in the United States, and college counselors should be familiar with this practice due to its popularity among college students. This article provides a brief overview of yoga and research on its benefits for mental health concerns often experienced by college students. Additionally, it addresses methods of…

  6. EnviroAtlas: Incorporation of Community-Scale Data for Additional Communities

    EPA Science Inventory

    EnviroAtlas is ORD’s online spatial decision support tool for viewing and analyzing the supply, demand, and drivers of change related to natural and built infrastructure at multiple scales for the nation. Maps and text identify known relationships between the goods and services ...

  7. Electronically nonadiabatic wave packet propagation using frozen Gaussian scattering

    NASA Astrophysics Data System (ADS)

    Kondorskiy, Alexey D.; Nanbu, Shinkoh

    2015-09-01

    We present an approach, which allows to employ the adiabatic wave packet propagation technique and semiclassical theory to treat the nonadiabatic processes by using trajectory hopping. The approach developed generates a bunch of hopping trajectories and gives all additional information to incorporate the effect of nonadiabatic coupling into the wave packet dynamics. This provides an interface between a general adiabatic frozen Gaussian wave packet propagation method and the trajectory surface hopping technique. The basic idea suggested in [A. D. Kondorskiy and H. Nakamura, J. Chem. Phys. 120, 8937 (2004)] is revisited and complemented in the present work by the elaboration of efficient numerical algorithms. We combine our approach with the adiabatic Herman-Kluk frozen Gaussian approximation. The efficiency and accuracy of the resulting method is demonstrated by applying it to popular benchmark model systems including three Tully's models and 24D model of pyrazine. It is shown that photoabsorption spectrum is successfully reproduced by using a few hundreds of trajectories. We employ the compact finite difference Hessian update scheme to consider feasibility of the ab initio "on-the-fly" simulations. It is found that this technique allows us to obtain the reliable final results using several Hessian matrix calculations per trajectory.

  8. Electronically nonadiabatic wave packet propagation using frozen Gaussian scattering

    SciTech Connect

    Kondorskiy, Alexey D.; Nanbu, Shinkoh

    2015-09-21

    We present an approach, which allows to employ the adiabatic wave packet propagation technique and semiclassical theory to treat the nonadiabatic processes by using trajectory hopping. The approach developed generates a bunch of hopping trajectories and gives all additional information to incorporate the effect of nonadiabatic coupling into the wave packet dynamics. This provides an interface between a general adiabatic frozen Gaussian wave packet propagation method and the trajectory surface hopping technique. The basic idea suggested in [A. D. Kondorskiy and H. Nakamura, J. Chem. Phys. 120, 8937 (2004)] is revisited and complemented in the present work by the elaboration of efficient numerical algorithms. We combine our approach with the adiabatic Herman-Kluk frozen Gaussian approximation. The efficiency and accuracy of the resulting method is demonstrated by applying it to popular benchmark model systems including three Tully’s models and 24D model of pyrazine. It is shown that photoabsorption spectrum is successfully reproduced by using a few hundreds of trajectories. We employ the compact finite difference Hessian update scheme to consider feasibility of the ab initio “on-the-fly” simulations. It is found that this technique allows us to obtain the reliable final results using several Hessian matrix calculations per trajectory.

  9. Waves in Plasmas

    SciTech Connect

    Tracy, Eugene R

    2009-09-21

    Quadratic corrections to the metaplectic formulation of mode conversions. In this work we showed how to systematically deal with quadratic corrections beyond the usual linearization of the dispersion matrix at a conversion. The linearization leads to parabolic cylinder functions as the local approximation to the full-wave behavior, but these do not include the variation in amplitude associated with ray refraction in the neighborhood of the conversion. Hence, the region over which they give a good fit to the incoming and outgoing WKB solutions is small. By including higher order corrections it is possible to provide a much more robust matching. We also showed that it was possible, in principle, to extend these methods to arbitrary order. A new normal form for mode conversion. This is based upon our earlier NSF-DOE-funded work on ray helicity. We have begun efforts to apply these new ideas in practical ray tracing algorithms. Group theoretical foundation of path integrals and phase space representations of wave problems. Using the symbol theory of N. Zobin, we developed a new understanding of path integrals on phase space. The initial goal was to find practical computational tools for dealing with non-standard mode conversions. Along the way we uncovered a new way to represent wave functions directly on phase space without the intermediary of a Wigner function. We are exploring the use of these ideas for numerical studies of conversion, with the goal of eventually incorporating kinetic effects. Wave packet studies of gyroresonance crossing. In earlier work, Huanchun Ye and Allan Kaufman -- building upon ideas due to Lazar Friedland -- had shown that gyroresonance crossings could be treated as a double conversion. This perspective is one we have used for many of our papers since then. We are now performing a detailed numerical comparison between full-wave and ray tracing approaches in the study of minority-ion gyroresonance crossing. In this study, a fast magnetosonic

  10. Making Waves: Seismic Waves Activities and Demonstrations

    NASA Astrophysics Data System (ADS)

    Braile, S. J.; Braile, L. W.

    2011-12-01

    The nature and propagation of seismic waves are fundamental concepts necessary for understanding the exploration of Earth's interior structure and properties, plate tectonics, earthquakes, and seismic hazards. Investigating seismic waves is also an engaging approach to learning basic principles of the physics of waves and wave propagation. Several effective educational activities and demonstrations are available for teaching about seismic waves, including the stretching of a spring to demonstrate elasticity; slinky wave propagation activities for compressional, shear, Rayleigh and Love waves; the human wave activity to demonstrate P- and S- waves in solids and liquids; waves in water in a simple wave tank; seismic wave computer animations; simple shake table demonstrations of model building responses to seismic waves to illustrate earthquake damage to structures; processing and analysis of seismograms using free and easy to use software; and seismic wave simulation software for viewing wave propagation in a spherical Earth. The use of multiple methods for teaching about seismic waves is useful because it provides reinforcement of the fundamental concepts, is adaptable to variable classroom situations and diverse learning styles, and allows one or more methods to be used for authentic assessment. The methods described here have been used effectively with a broad range of audiences, including K-12 students and teachers, undergraduate students in introductory geosciences courses, and geosciences majors.

  11. Mesosphere Dynamics with Gravity Wave Forcing. 2; Planetary Waves

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Mengel, J. G.; Chan, K. L.; Porter, H. S.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    We present results from a non-linear, 3D, time dependent numerical spectral model (NSM) which extends from the ground up into the thermosphere and incorporates Hines' Doppler Spread Parameterization for small-scale gravity waves (GW). Our focal point is the mesosphere where wave interactions are playing a dominant role. We discuss planetary waves in the present paper and diurnal and semi-diurnal tides in the companion paper. Without external time dependent energy or momentum sources, planetary waves (PWs) are generated in the model for zonal wavenumbers 1 to 4, which have amplitudes in the mesosphere above 50 km as large as 30 m/s and periods between 2 and 50 days. The waves are generated primarily during solstice conditions, which indicates that the baroclinic instability (associated with the GW driven reversal in the latitudinal temperature gradient) is playing an important role. Results from a numerical experiment show that GWs are also involved directly in generating the PWs. For the zonal wavenumber m = 1, the predominant wave periods in summer are around 4 days and in winter between 6 and 10 days. For m = 2, the periods are in summer and close to 2.5 and 3.5 days respectively For m = 3, 4 the predominant wave periods are in both seasons close to two days. The latter waves have the characteristics of Rossby gravity waves with meridional winds at equatorial latitudes. A common feature of the PWs (m = 1 to 4) generated in summer and winter is that their vertical wavelengths throughout the mesosphere are large which indicates that the waves are not propagating freely but are generated throughout the region. Another common feature is that the PWs propagate preferentially westward in summer and eastward in winter, being launched from the westward and eastward zonal winds that prevail respectively in summer and winter altitudes below 80 km. During spring and fall, for m = 1 and 2 eastward propagating long period PWs are generated that are launched from the smaller

  12. Breaking of waves in deep water

    NASA Astrophysics Data System (ADS)

    Ruiz-Chavarria, Gerardo

    2013-11-01

    The breaking of waves is a nonlinear phenomenon during which a fraction of the energy is dissipated. In the previous stage the wave undergoes a growth of its amplitude and the wave pattern is modified in the sense that the crests become more pronounced than the troughs. The breaking has been extensively studied in the case of waves approaching the shore. However, the wave breaking in deep water remains an open problem in fluid dynamics. In this work we study the wave breaking due to focusing of an initially parabolic wave front. To this end the evolution of wave is numerically investigated using a meshless code (Smoothed Particle Hydrodynamics). We present some results about the evolution of waves excited by a parabolic wave maker, among others, the growth induced by the focusing, the behavior around the Huygens' cusp and the process of wave breaking. Then, we compare the numerical results with the criteria given in the literature about the onset of breaking and we discuss how the energy dissipates, for example by the rise of short waves. In addition we compare the numerical results with data obtained in two different experiments made by our team. Author acknowledges DGAPA-UNAM by support under project IN116312, ``Vorticidad y ondas no lineales en fluidos.''

  13. Retroviral env glycoprotein trafficking and incorporation into virions.

    PubMed

    Murakami, Tsutomu

    2012-01-01

    Together with the Gag protein, the Env glycoprotein is a major retroviral structural protein and is essential for forming infectious virus particles. Env is synthesized, processed, and transported to certain microdomains at the plasma membrane and takes advantage of the same host machinery for its trafficking as that used by cellular glycoproteins. Incorporation of Env into progeny virions is probably mediated by the interaction between Env and Gag, in some cases with the additional involvement of certain host factors. Although several general models have been proposed to explain the incorporation of retroviral Env glycoproteins into virions, the actual mechanism for this process is still unclear, partly because structural data on the Env protein cytoplasmic tail is lacking. This paper presents the current understanding of the synthesis, trafficking, and virion incorporation of retroviral Env proteins.

  14. Immediate tool incorporation processes determine human motor planning with tools.

    PubMed

    Ganesh, G; Yoshioka, T; Osu, R; Ikegami, T

    2014-01-01

    Human dexterity with tools is believed to stem from our ability to incorporate and use tools as parts of our body. However tool incorporation, evident as extensions in our body representation and peri-personal space, has been observed predominantly after extended tool exposures and does not explain our immediate motor behaviours when we change tools. Here we utilize two novel experiments to elucidate the presence of additional immediate tool incorporation effects that determine motor planning with tools. Interestingly, tools were observed to immediately induce a trial-by-trial, tool length dependent shortening of the perceived limb lengths, opposite to observations of elongations after extended tool use. Our results thus exhibit that tools induce a dual effect on our body representation; an immediate shortening that critically affects motor planning with a new tool, and the slow elongation, probably a consequence of skill related changes in sensory-motor mappings with the repeated use of the tool. PMID:25077612

  15. How Forgetful are Seismic Waves ?

    NASA Astrophysics Data System (ADS)

    Milkereit, B.

    2005-05-01

    3D surface seismic and vertical seismic profiling (VSP) techniques can be employed to image crustal structures in complex geological settings. The effects of heterogeneities on seismic wave propagation can be described in terms of different propagation regimes (Wu, 1989): quasi-homogeneous for heterogeneities too small to be seen by seismic waves, Rayleigh scattering, Mie scattering and small-angle scattering. These scattering regimes cause characteristic amplitude, phase and travel time fluctuation, which can be used to obtain estimates of scale length. Horizontal resolution of exploration seismic data is often discussed in terms of Fresnel zone. For surface and VSP data, the Fresnel radius increases with increasing depth of investigation. In addition, the lateral resolution is limited by the effective frequency content of the seismic signal. Based on strong contrast in petrophysical data, crustal exploration targets (such as gas-hydrates, permafrost or massive sulfide ores) should make strong P-wave, S-wave and converted wave reflectors against most background velocity models. In the context of realistic geological models, 3D numerical simulations are required to better assess elastic wave interactions with high acoustic impedance targets. In addition, it is important to study the influence of composition and shape of high acoustic impedance targets on the full scattered wavefield through a series of numerical modeling experiments based on the 3D elastic finite-difference (FD) method. Massive sulfide ores consisting of the end-member sulfide minerals pyrite, sphalerite, and galena, which span the full range of observed P- and S- wave velocities and densities in ore rocks, as well as gabbro inclusions, are investigated for different shapes which represent the complex morphologies often observed for ore deposits. 3D FD modeling reveals that large ore deposits lead to a strong and complex scattering response that is often dominated by shear-wave events (Bohlen et al

  16. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  17. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  18. Advances in real-time millimeter-wave imaging radiometers for avionic synthetic vision

    NASA Astrophysics Data System (ADS)

    Lovberg, John A.; Chou, Ri-Chee; Martin, Christopher A.; Galliano, Joseph A., Jr.

    1995-06-01

    Millimeter-wave imaging has advantages over conventional visible or infrared imaging for many applications because millimeter-wave signals can travel through fog, snow, dust, and clouds with much less attenuation than infrared or visible light waves. Additionally, passive imaging systems avoid many problems associated with active radar imaging systems, such as radar clutter, glint, and multi-path return. ThermoTrex Corporation previously reported on its development of a passive imaging radiometer that uses an array of frequency-scanned antennas coupled to a multichannel acousto-optic spectrum analyzer (Bragg-cell) to form visible images of a scene through the acquisition of thermal blackbody radiation in the millimeter-wave spectrum. The output from the Bragg cell is imaged by a standard video camera and passed to a computer for normalization and display at real-time frame rates. An application of this system is its incorporation as part of an enhanced vision system to provide pilots with a synthetic view of a runway in fog and during other adverse weather conditions. Ongoing improvements to a 94 GHz imaging system and examples of recent images taken with this system will be presented. Additionally, the development of dielectric antennas and an electro- optic-based processor for improved system performance, and the development of an `ultra- compact' 220 GHz imaging system will be discussed.

  19. Emergent cosmological constant from colliding electromagnetic waves

    SciTech Connect

    Halilsoy, M.; Mazharimousavi, S. Habib; Gurtug, O. E-mail: habib.mazhari@emu.edu.tr

    2014-11-01

    In this study we advocate the view that the cosmological constant is of electromagnetic (em) origin, which can be generated from the collision of em shock waves coupled with gravitational shock waves. The wave profiles that participate in the collision have different amplitudes. It is shown that, circular polarization with equal amplitude waves does not generate cosmological constant. We also prove that the generation of the cosmological constant is related to the linear polarization. The addition of cross polarization generates no cosmological constant. Depending on the value of the wave amplitudes, the generated cosmological constant can be positive or negative. We show additionally that, the collision of nonlinear em waves in a particular class of Born-Infeld theory also yields a cosmological constant.

  20. Wave chaotic experiments and models for complicated wave scattering systems

    NASA Astrophysics Data System (ADS)

    Yeh, Jen-Hao

    Wave scattering in a complicated environment is a common challenge in many engineering fields because the complexity makes exact solutions impractical to find, and the sensitivity to detail in the short-wavelength limit makes a numerical solution relevant only to a specific realization. On the other hand, wave chaos offers a statistical approach to understand the properties of complicated wave systems through the use of random matrix theory (RMT). A bridge between the theory and practical applications is the random coupling model (RCM) which connects the universal features predicted by RMT and the specific details of a real wave scattering system. The RCM gives a complete model for many wave properties and is beneficial for many physical and engineering fields that involve complicated wave scattering systems. One major contribution of this dissertation is that I have utilized three microwave systems to thoroughly test the RCM in complicated wave systems with varied loss, including a cryogenic system with a superconducting microwave cavity for testing the extremely-low-loss case. I have also experimentally tested an extension of the RCM that includes short-orbit corrections. Another novel result is development of a complete model based on the RCM for the fading phenomenon extensively studied in the wireless communication fields. This fading model encompasses the traditional fading models as its high-loss limit case and further predicts the fading statistics in the low-loss limit. This model provides the first physical explanation for the fitting parameters used in fading models. I have also applied the RCM to additional experimental wave properties of a complicated wave system, such as the impedance matrix, the scattering matrix, the variance ratio, and the thermopower. These predictions are significant for nuclear scattering, atomic physics, quantum transport in condensed matter systems, electromagnetics, acoustics, geophysics, etc.

  1. Plasma waves in the magnetotail of Uranus

    NASA Astrophysics Data System (ADS)

    Kurth, W. S.; Gurnett, D. A.; Scarf, F. L.; Mauk, B. H.

    1989-04-01

    Plasma wave phenomena observed during the Voyager 2 passing through the magnetotail of Uranus after its encounter with the planet on January 24, 1986 are described. The location of the wave events, their probable mode of propagation, and their association with various plasma and charged particle observations are presented. It was found that the most remarkable magnetotail plasma waves were inside the distance of about 23 Uranus radii, with an additional event occurring between about 48 and 56 Uranus radii. The frequency of these magnetotail plasma waves was found to be below about 100 Hz, extending down to the 10-Hz lower frequency limit of the receiver. The shape of the spectrum and the location of the wave activity near the boundary layer suggest that these waves may be similar to broadband electrostatic waves observed in similar regions of the earth's magnetotail.

  2. Refraction of coastal ocean waves

    NASA Technical Reports Server (NTRS)

    Shuchman, R. A.; Kasischke, E. S.

    1981-01-01

    Refraction of gravity waves in the coastal area off Cape Hatteras, NC as documented by synthetic aperture radar (SAR) imagery from Seasat orbit 974 (collected on September 3, 1978) is discussed. An analysis of optical Fourier transforms (OFTs) from more than 70 geographical positions yields estimates of wavelength and wave direction for each position. In addition, independent estimates of the same two quantities are calculated using two simple theoretical wave-refraction models. The OFT results are then compared with the theoretical results. A statistical analysis shows a significant degree of linear correlation between the data sets. This is considered to indicate that the Seasat SAR produces imagery whose clarity is sufficient to show the refraction of gravity waves in shallow water.

  3. Additional Types of Neuropathy

    MedlinePlus

    ... A A Listen En Español Additional Types of Neuropathy Charcot's Joint Charcot's Joint, also called neuropathic arthropathy, ... can stop bone destruction and aid healing. Cranial Neuropathy Cranial neuropathy affects the 12 pairs of nerves ...

  4. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  5. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  6. Dust-acoustic solitary waves and double layers in a magnetized dusty plasma with nonthermal ions and dust charge variation

    SciTech Connect

    El-Taibany, W.F.; Sabry, R.

    2005-08-15

    The effect of nonthermal ions and variable dust charge on small-amplitude nonlinear dust-acoustic (DA) waves is investigated. It is found that both compressive and rarefactive solitons exist and depend on the nonthermal parameter a. Using a reductive perturbation theory, a Zakharov-Kuznetsov (ZK) equation is derived. At critical value of a, a{sub c}, a modified ZK equation with third- and fourth-order nonlinearities, is obtained. Depending on a, the solution of the evolution equation reveals whether there is coexistence of both compressive and rarefactive solitary waves or double layers (DLs) with the possibility of their two kinds. In addition, for certain plasma parameters, the solitary wave disappears and a DL is expected. The variation of dust charge number, wave velocity, and soliton amplitude and its width against system parameters is investigated for the DA solitary waves. It is shown that the incorporation of both the adiabatic dust-charge variation and the nonthermal distributed ions modifies significantly the nature of DA solitary waves and DA DLs. The findings of this investigation may be useful in understanding the ion acceleration mechanisms close to the Moon and also enhances our knowledge on pickup ions around unmagnetized bodies, such as comets, Mars, and Venus.

  7. Two-wave propagation in in vitro swine distal ulna

    NASA Astrophysics Data System (ADS)

    Mano, Isao; Horii, Kaoru; Matsukawa, Mami; Otani, Takahiko

    2015-07-01

    Ultrasonic transmitted waves were obtained in an in vitro swine distal ulna specimen, which mimics a human distal radius, that consists of interconnected cortical bone and cancellous bone. The transmitted waveforms appeared similar to the fast waves, slow waves, and overlapping fast and slow waves measured in the specimen after removing the surface cortical bone (only cancellous bone). In addition, the circumferential waves in the cortical bone and water did not affect the fast and slow waves. This suggests that the fast-and-slow-wave phenomenon can be observed in an in vivo human distal radius.

  8. Quantum-mechanical evaluation of Np-incorporation into studtite

    SciTech Connect

    Shuller, Lindsay C.; Ewing, Rodney C.; Becker, Udo

    2010-08-05

    Radionuclide incorporation into the alteration products of corroded UO2 in used nuclear fuel may control the release and mobility of key radionuclides, such as the very long-lived minor actinide, 237Np (τ ½ = 2.1 Ma). Studtite, [UO2(O2)(H2O)2](H2O)2, may form in the presence of peroxide produced by radiolysis of water in contact with the spent fuel. Experiments have indicated that the studtite structure can incorporate Np; however, due to the low concentrations in the solid, the incorporation mechanism could not be determined. In this study, density functional theory is used to calculate an optimized structure, determine the electronic density of states, and calculate the energetics of the incorporation of Np 6+ vs. Np5++H+ into the studtite structure. The definition of the source/sink phase (reference phase) for the cations involved in the incorporation process greatly affects the final incorporation energy. The incorporation energy of Np into studtite based on the 4+ oxide reference phases (e.g., source/sink = NpO2/UO2) results in lower incorporation energies (-0.07 and 0.63 eV for Np6+ and Np5+ incorporation, respectively) than the incorporation energy calculated using higher-oxide reference phases (e.g., Np2O5/UO3), where the incorporation energies for Np5+ and Np5+ into studtite are 0.42 and 1.12 eV, respectively. In addition, Np6+-incorporation into studtite is energetically more favorable than Np5+-incorporation as assessed from the lower incorporation energy. Estimates of the solid-solution behavior from a combination of quantum-mechanical calculations and Monte-Carlo simulations indicate that the Np6+- and U6+-studtite solid solution is completely miscible at room temperature with

  9. MHD simple waves and the divergence wave

    SciTech Connect

    Webb, G. M.; Pogorelov, N. V.; Zank, G. P.

    2010-03-25

    In this paper we investigate magnetohydrodynamic (MHD) simple divergence waves in MHD, for models in which nablacentre dotBnot =0. These models are related to the eight wave Riemann solvers in numerical MHD, in which the eighth wave is the divergence wave associated with nablacentre dotBnot =0. For simple wave solutions, all physical variables (the gas density, pressure, fluid velocity, entropy, and magnetic field induction in the MHD case) depend on a single phase function phi. We consider the form of the MHD equations used by both Powell et al. and Janhunen. It is shown that the Janhunen version of the equations possesses fully nonlinear, exact simple wave solutions for the divergence wave, but no physically meaningful simple divergence wave solution exists for the Powell et al. system. We suggest that the 1D simple, divergence wave solution for the Janhunen system, may be useful for the testing and validation of numerical MHD codes.

  10. Head waves, diving waves, and interface waves at the seafloor

    NASA Astrophysics Data System (ADS)

    Stephen, Ralph A.

    2005-09-01

    Brekhovskikh (1960) summarizes the system of waves that arises from reflection and refraction of spherical waves at the interface between homogeneous solid half-spaces. By eliminating the shear wave potential in one half-space, the system for fluid-solid half-spaces like the seafloor is obtained. There are two cases: one where the shear speed in the bottom is less than the compressional speed in the fluid (soft sediments), and the other where the shear speed in the bottom is greater than the compressional speed in the fluid (hard volcanic basement). This model is the basis for defining interface phenomena such as evanescent waves, head waves, pseudo-Rayleigh waves, and Stoneley/Scholte waves. If a positive gradient is introduced into the compressional and shear sound speeds in the bottom, one obtains diving waves and interference head waves (Cerveny and Ravindra, 1971). There are two types of interface waves: pseudo-Rayleigh waves that are evanescent in the bottom but propagate in the water, and Stoneley/Scholte waves that are evanescent in both media. In multi-interface models there are of course normal modes. In actual seafloors, low speed layers, sound and shear speed gradients, and interface and volume lateral heterogeneities affect the characteristics of propagation and scattering. [Work supported by ONR.

  11. In vitro incorporation of LNA nucleotides.

    PubMed

    Veedu, Rakesh N; Vester, Birte; Wengel, Jesper

    2007-01-01

    An LNA modified nucleoside triphosphate 1 was synthesized in order to investigate its potential to act as substrate for DNA strand synthesis by polymerases. Primer extension assays for the incorporation experiments revealed that Phusion High Fidelity DNA polymerase is an efficient enzyme for incorporation of the LNA nucleotide and for extending strand to full length. It was also observed that pfu DNA polymerase could incorporate the LNA nucleotide but it failed to extend the strand to a full length product. PMID:18058567

  12. Questionnaire for biotechs: Vical incorporated.

    PubMed

    Bilinsky, Igor P; Smith, Larry R

    2014-01-01

    This feature contains forward-looking statements subject to risks and uncertainties that could cause actual results to differ materially from those projected. Forward-looking statements include statements about the company's focus, collaborative partners, product candidates, and developmental status. Risks and uncertainties include whether any product candidates will be shown to be safe and efficacious in clinical trials, the timing of clinical trials, whether Vical or its collaborative partners will seek or gain approval to market any product candidates, the dependence of the company on its collaborative partners, and additional risks set forth in the company's filings with the Securities and Exchange Commission. These forward-looking statements represent the company's judgment as of the date of this release. The company disclaims, however, any intent or obligation to update these forward-looking statements.

  13. Waves and Tsunami Project

    ERIC Educational Resources Information Center

    Frashure, K. M.; Chen, R. F.; Stephen, R. A.; Bolmer, T.; Lavin, M.; Strohschneider, D.; Maichle, R.; Micozzi, N.; Cramer, C.

    2007-01-01

    Demonstrating wave processes quantitatively in the classroom using standard classroom tools (such as Slinkys and wave tanks) can be difficult. For example, waves often travel too fast for students to actually measure amplitude or wavelength. Also, when teaching propagating waves, reflections from the ends set up standing waves, which can confuse…

  14. Periodontal tissue regeneration with PRP incorporated gelatin hydrogel sponges.

    PubMed

    Nakajima, Dai; Tabata, Yasuhiko; Sato, Soh

    2015-10-20

    Gelatin hydrogels have been designed and prepared for the controlled release of the transforming growth factor (TGF-b1) and the platelet-derived growth factor (PDGF-BB). PRP (Platelet rich plasma) contains many growth factors including the PDGF and TGF-b1. The objective of this study was to evaluate the regeneration of periodontal tissue following the controlled release of growth factors in PRP. For the periodontal ligament cells and osteoblast, PRP of different concentrations was added. The assessment of DNA, mitochondrial activity and ALP activity were measured. To evaluate the TGF-β1 release from PRP incorporated gelatin sponge, amounts of TGF-β1 in each supernatant sample were determined by the ELISA. Transplantation experiments to prepare a bone defect in a rat alveolar bone were an implanted gelatin sponge incorporated with different concentration PRP. In DNA assay and MTT assay, after the addition of PRP to the periodontal ligament cells and osteoblast, the cell count and mitochondrial activity had increased the most in the group with the addition of 5  ×  PRP. In the ALP assay, after the addition of PRP to the periodontal ligament cells, the cell activity had increased the most in the group with the addition of 3  ×  PRP. In the transplantation, the size of the bone regenerated in the defect with 3  ×  PRP incorporated gelatin sponge was larger than that of the other group.

  15. On a class of nonlocal wave equations from applications

    NASA Astrophysics Data System (ADS)

    Beyer, Horst Reinhard; Aksoylu, Burak; Celiker, Fatih

    2016-06-01

    We study equations from the area of peridynamics, which is a nonlocal extension of elasticity. The governing equations form a system of nonlocal wave equations. We take a novel approach by applying operator theory methods in a systematic way. On the unbounded domain ℝn, we present three main results. As main result 1, we find that the governing operator is a bounded function of the governing operator of classical elasticity. As main result 2, a consequence of main result 1, we prove that the peridynamic solutions strongly converge to the classical solutions by utilizing, for the first time, strong resolvent convergence. In addition, main result 1 allows us to incorporate local boundary conditions, in particular, into peridynamics. This avenue of research is developed in companion papers, providing a remedy for boundary effects. As main result 3, employing spherical Bessel functions, we give a new practical series representation of the solution which allows straightforward numerical treatment with symbolic computation.

  16. Nonlinear evolution of Alfven waves in a finite beta plasma

    SciTech Connect

    Som, B.K. ); Dasgupta, B.; Patel, V.L. ); Gupta, M.R. )

    1989-12-01

    A general form of the derivative nonlinear Schroedinger (DNLS) equation, describing the nonlinear evolution of Alfven waves propagating parallel to the magnetic field, is derived by using two-fluid equations with electron and ion pressure tensors obtained from Braginskii (in {ital Reviews} {ital of} {ital Plasma Physics} (Consultants Bureau, New York, 1965), Vol. 1, p. 218). This equation is a mixed version of the nonlinear Schroedinger (NLS) equation and the DNLS, as it contains an additional cubic nonlinear term that is of the same order as the derivative of the nonlinear terms, a term containing the product of a quadratic term, and a first-order derivative. It incorporates the effects of finite beta, which is an important characteristic of space and laboratory plasmas.

  17. Incorporation of polydiacetylene sensors into commercial polymers

    NASA Astrophysics Data System (ADS)

    Kauffman, Jennifer Susan

    Polydiacetylenes (PDAs) exhibit a chromatic response to solvents, temperature, strain and other environmental perturbations. When formed in a solid-state polymerization, the backbone of the polymer is planar and continuous pi-overlap is observed. However, when the PDA backbone is distorted by an outside force the extended conjugation is interrupted and an optical shift from blue to red is observed. By exploiting the PDAs properties within polymer systems, smart fibers and films have been created that enhance the original intention of the host. Under this umbrella, a strain sensitive polydiacetylene-polyurethane blend was created using 3 and 4-butoxycarbonylmethylurethane PDA and a medical grade polyurethane, TecoflexRTM. Additionally, a temperature sensitive material has been developed with the renewable resource polymer, polylactic acid (PLA) blended with 10,12-pentacosadiynoic acid (PCDA). Finally, PCDA has been incorporated into sodium alginate to be used as environmentally responsive fibers. To match the aqueous solubility of the alginate, the PCDA was forced into a micellular structure through heating and probe sonication. After crystallization and polymerization, the water-soluble micelles were combined with the sodium alginate and wet-spun into calcium alginate "smart" fibers. The visual colorimetric detection (blue to red) was monitored optically and quantitatively by absorbance and Raman spectroscopy.

  18. Incorporating climate change into systematic conservation planning

    USGS Publications Warehouse

    Groves, Craig R.; Game, Edward T.; Anderson, Mark G.; Cross, Molly; Enquist, Carolyn; Ferdana, Zach; Girvetz, Evan; Gondor, Anne; Hall, Kimberly R.; Higgins, Jonathan; Marshall, Rob; Popper, Ken; Schill, Steve; Shafer, Sarah L.

    2012-01-01

    The principles of systematic conservation planning are now widely used by governments and non-government organizations alike to develop biodiversity conservation plans for countries, states, regions, and ecoregions. Many of the species and ecosystems these plans were designed to conserve are now being affected by climate change, and there is a critical need to incorporate new and complementary approaches into these plans that will aid species and ecosystems in adjusting to potential climate change impacts. We propose five approaches to climate change adaptation that can be integrated into existing or new biodiversity conservation plans: (1) conserving the geophysical stage, (2) protecting climatic refugia, (3) enhancing regional connectivity, (4) sustaining ecosystem process and function, and (5) capitalizing on opportunities emerging in response to climate change. We discuss both key assumptions behind each approach and the trade-offs involved in using the approach for conservation planning. We also summarize additional data beyond those typically used in systematic conservation plans required to implement these approaches. A major strength of these approaches is that they are largely robust to the uncertainty in how climate impacts may manifest in any given region.

  19. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  20. Incorporating neurophysiological concepts in mathematical thermoregulation models

    NASA Astrophysics Data System (ADS)

    Kingma, Boris R. M.; Vosselman, M. J.; Frijns, A. J. H.; van Steenhoven, A. A.; van Marken Lichtenbelt, W. D.

    2014-01-01

    Skin blood flow (SBF) is a key player in human thermoregulation during mild thermal challenges. Various numerical models of SBF regulation exist. However, none explicitly incorporates the neurophysiology of thermal reception. This study tested a new SBF model that is in line with experimental data on thermal reception and the neurophysiological pathways involved in thermoregulatory SBF control. Additionally, a numerical thermoregulation model was used as a platform to test the function of the neurophysiological SBF model for skin temperature simulation. The prediction-error of the SBF-model was quantified by root-mean-squared-residual (RMSR) between simulations and experimental measurement data. Measurement data consisted of SBF (abdomen, forearm, hand), core and skin temperature recordings of young males during three transient thermal challenges (1 development and 2 validation). Additionally, ThermoSEM, a thermoregulation model, was used to simulate body temperatures using the new neurophysiological SBF-model. The RMSR between simulated and measured mean skin temperature was used to validate the model. The neurophysiological model predicted SBF with an accuracy of RMSR < 0.27. Tskin simulation results were within 0.37 °C of the measured mean skin temperature. This study shows that (1) thermal reception and neurophysiological pathways involved in thermoregulatory SBF control can be captured in a mathematical model, and (2) human thermoregulation models can be equipped with SBF control functions that are based on neurophysiology without loss of performance. The neurophysiological approach in modelling thermoregulation is favourable over engineering approaches because it is more in line with the underlying physiology.

  1. Incorporating neurophysiological concepts in mathematical thermoregulation models.

    PubMed

    Kingma, Boris R M; Vosselman, M J; Frijns, A J H; van Steenhoven, A A; van Marken Lichtenbelt, W D

    2014-01-01

    Skin blood flow (SBF) is a key player in human thermoregulation during mild thermal challenges. Various numerical models of SBF regulation exist. However, none explicitly incorporates the neurophysiology of thermal reception. This study tested a new SBF model that is in line with experimental data on thermal reception and the neurophysiological pathways involved in thermoregulatory SBF control. Additionally, a numerical thermoregulation model was used as a platform to test the function of the neurophysiological SBF model for skin temperature simulation. The prediction-error of the SBF-model was quantified by root-mean-squared-residual (RMSR) between simulations and experimental measurement data. Measurement data consisted of SBF (abdomen, forearm, hand), core and skin temperature recordings of young males during three transient thermal challenges (1 development and 2 validation). Additionally, ThermoSEM, a thermoregulation model, was used to simulate body temperatures using the new neurophysiological SBF-model. The RMSR between simulated and measured mean skin temperature was used to validate the model. The neurophysiological model predicted SBF with an accuracy of RMSR < 0.27. Tskin simulation results were within 0.37 °C of the measured mean skin temperature. This study shows that (1) thermal reception and neurophysiological pathways involved in thermoregulatory SBF control can be captured in a mathematical model, and (2) human thermoregulation models can be equipped with SBF control functions that are based on neurophysiology without loss of performance. The neurophysiological approach in modelling thermoregulation is favourable over engineering approaches because it is more in line with the underlying physiology.

  2. Constraints on Noun Incorporation in Korean.

    ERIC Educational Resources Information Center

    Khym, Hangyoo

    1997-01-01

    A study of the noun incorporation phenomenon in Korean suggests that noun incorporation occurs at D-structure and obeys the Head Movement Constraint syntactically, and the Theme-Only Constraint semantically. First, the structure of "sunrise"-type words is identified, showing that before derivation through nominalization of the affix "-i,"…

  3. 10 CFR 218.31 - Incorporated procedures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Incorporated procedures. 218.31 Section 218.31 Energy DEPARTMENT OF ENERGY OIL STANDBY MANDATORY INTERNATIONAL OIL ALLOCATION Procedures § 218.31 Incorporated procedures. The following subparts of part 205 of this chapter are, as appropriate, hereby made applicable...

  4. 49 CFR 572.180 - Incorporated materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51....187; (x) Drawing No. 175-6000, Pelvis Assembly, incorporated by reference in §§ 572.181 and...

  5. 49 CFR 572.180 - Incorporated materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51....187; (x) Drawing No. 175-6000, Pelvis Assembly, incorporated by reference in §§ 572.181 and...

  6. 49 CFR 572.180 - Incorporated materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... approved the materials incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51....187; (x) Drawing No. 175-6000, Pelvis Assembly, incorporated by reference in §§ 572.181 and...

  7. Incorporating Sociology into Community Service Classes

    ERIC Educational Resources Information Center

    Hochschild, Thomas R., Jr.; Farley, Matthew; Chee, Vanessa

    2014-01-01

    Sociologists and instructors who teach about community service share an affinity for understanding and addressing social problems. While many studies have demonstrated the benefits of incorporating community service into sociology courses, we examine the benefits of incorporating sociological content into community service classes. The authors…

  8. 49 CFR 572.40 - Incorporated materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.40 Section 572.40... Percentile Male § 572.40 Incorporated materials. (a) The drawings, specifications, manual, and computer... by reference. These materials are thereby made part of this regulation. The Director of the...

  9. 49 CFR 572.40 - Incorporated materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Incorporated materials. 572.40 Section 572.40... Percentile Male § 572.40 Incorporated materials. (a) The drawings, specifications, manual, and computer... by reference. These materials are thereby made part of this regulation. The Director of the...

  10. 49 CFR 572.40 - Incorporated materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 7 2014-10-01 2014-10-01 false Incorporated materials. 572.40 Section 572.40... Percentile Male § 572.40 Incorporated materials. (a) The drawings, specifications, manual, and computer... by reference. These materials are thereby made part of this regulation. The Director of the...

  11. 49 CFR 572.40 - Incorporated materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Incorporated materials. 572.40 Section 572.40... Percentile Male § 572.40 Incorporated materials. (a) The drawings, specifications, manual, and computer... by reference. These materials are thereby made part of this regulation. The Director of the...

  12. 49 CFR 572.40 - Incorporated materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Incorporated materials. 572.40 Section 572.40... Percentile Male § 572.40 Incorporated materials. (a) The drawings, specifications, manual, and computer... by reference. These materials are thereby made part of this regulation. The Director of the...

  13. Multifunctional fuel additives

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-26

    This paper discusses a composition comprising a major amount of a liquid hydrocarbyl fuel and a minor low-temperature flow properties improving amount of an additive product of the reaction of a suitable diol and product of a benzophenone tetracarboxylic dianhydride and a long-chain hydrocarbyl aminoalcohol.

  14. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  15. WAVDRAG- ZERO-LIFT WAVE DRAG OF COMPLEX AIRCRAFT CONFIGURATIONS

    NASA Technical Reports Server (NTRS)

    Craidon, C. B.

    1994-01-01

    WAVDRAG calculates the supersonic zero-lift wave drag of complex aircraft configurations. The numerical model of an aircraft is used throughout the design process from concept to manufacturing. WAVDRAG incorporates extended geometric input capabilities to permit use of a more accurate mathematical model. With WAVDRAG, the engineer can define aircraft components as fusiform or nonfusiform in terms of non-intersecting contours in any direction or more traditional parallel contours. In addition, laterally asymmetric configurations can be simulated. The calculations in WAVDRAG are based on Whitcomb's area-rule computation of equivalent-bodies, with modifications for supersonic speed. Instead of using a single equivalent-body, WAVDRAG calculates a series of equivalent-bodies, one for each roll angle. The total aircraft configuration wave drag is the integrated average of the equivalent-body wave drags through the full roll range of 360 degrees. WAVDRAG currently accepts up to 30 user-defined components containing a maximum of 50 contours as geometric input. Each contour contains a maximum of 50 points. The Mach number, angle-of-attack, and coordinates of angle-of-attack rotation are also input. The program warns of any fusiform-body line segments having a slope larger than the Mach angle. WAVDRAG calculates total drag and the wave-drag coefficient of the specified aircraft configuration. WAVDRAG is written in FORTRAN 77 for batch execution and has been implemented on a CDC CYBER 170 series computer with a central memory requirement of approximately 63K (octal) of 60 bit words. This program was developed in 1983.

  16. Geometrical versus wave optics under gravitational waves

    NASA Astrophysics Data System (ADS)

    Angélil, Raymond; Saha, Prasenjit

    2015-06-01

    We present some new derivations of the effect of a plane gravitational wave on a light ray. A simple interpretation of the results is that a gravitational wave causes a phase modulation of electromagnetic waves. We arrive at this picture from two contrasting directions, namely, null geodesics and Maxwell's equations, or geometric and wave optics. Under geometric optics, we express the geodesic equations in Hamiltonian form and solve perturbatively for the effect of gravitational waves. We find that the well-known time-delay formula for light generalizes trivially to massive particles. We also recover, by way of a Hamilton-Jacobi equation, the phase modulation obtained under wave optics. Turning then to wave optics—rather than solving Maxwell's equations directly for the fields, as in most previous approaches—we derive a perturbed wave equation (perturbed by the gravitational wave) for the electromagnetic four-potential. From this wave equation it follows that the four-potential and the electric and magnetic fields all experience the same phase modulation. Applying such a phase modulation to a superposition of plane waves corresponding to a Gaussian wave packet leads to time delays.

  17. Compaction Waves in Granular HMX

    SciTech Connect

    E. Kober; R. Menikoff

    1999-01-01

    Piston driven compaction waves in granular HMX are simulated with a two-dimensional continuum mechanics code in which individual grains are resolved. The constitutive properties of the grains are modeled with a hydrostatic pressure and a simple elastic-plastic model for the shear stress. Parameters are chosen to correspond to inert HMX. For a tightly packed random grain distribution (with initial porosity of 19%) we varied the piston velocity to obtain weak partly compacted waves and stronger fully compacted waves. The average stress and wave speed are compatible with the porous Hugoniot locus for uni- axial strain. However, the heterogeneities give rise to stress concentrations, which lead to localized plastic flow. For weak waves, plastic deformation is the dominant dissipative mechanism and leads to dispersed waves that spread out in time. In addition to dispersion, the granular heterogeneities give rise to subgrain spatial variation in the thermodynamic variables. The peaks in the temperature fluctuations, known as hot spots, are in the range such that they are the critical factor for initiation sensitivity.

  18. Incorporation of tryptophan analogues into the lantibiotic nisin.

    PubMed

    Zhou, Liang; Shao, Jinfeng; Li, Qian; van Heel, Auke J; de Vries, Marcel P; Broos, Jaap; Kuipers, Oscar P

    2016-05-01

    Lantibiotics are posttranslationally modified peptides with efficient inhibitory activity against various Gram-positive bacteria. In addition to the original modifications, incorporation of non-canonical amino acids can render new properties and functions to lantibiotics. Nisin is the most studied lantibiotic and contains no tryptophan residues. In this study, a system was constructed to incorporate tryptophan analogues into nisin, which included the modification machinery (NisBTC) and the overexpression of tryptophanyl-tRNA synthetase (TrpRS). Tryptophan and three different tryptophan analogues (5-fluoroTrp (5FW), 5-hydroxyTrp (5HW) and 5-methylTrp (5MeW)) were successfully incorporated at four different positions of nisin (I1W, I4W, M17W and V32W). The incorporation efficiency of tryptophan analogues into mutants I1W, M17W and V32W was over 97 %, while the mutant I4W showed relatively low incorporation efficiency (69-93 %). The variants with 5FW showed relatively higher production yield, while 5MeW-containing variants showed the lowest yield. The dehydration efficiency of serines or threonines was affected by the tryptophan mutants of I4W and V32W. The affinity of the peptides for the cation-ion exchange and reverse phase chromatography columns was significantly reduced when 5HW was incorporated. The antimicrobial activity of IIW and its 5FW analogue both decreased two times compared to that of nisin, while that of its 5HW analogue decreased four times. The 5FW analogue of I4W also showed two times decreased activity than nisin. However, the mutant M17W and its 5HW analogue both showed 32 times reduced activity relative to that of nisin.

  19. Incorporation of Nicotine into Silicone Coatings for Marine Applications

    NASA Astrophysics Data System (ADS)

    Jaramillo, Sandy Tuyet

    PDMS-based marine coatings presently used are limited by their inability to mitigate microfouling which limits their application to high speed vessels. PDMS coatings are favored when viable, due to their foul release properties of macrofouling organisms. Natural products have been investigated for antifouling properties for potential use in these marine antifouling coatings but few have incorporated natural products into coatings or coating systems. The purpose of the research was to establish the corrosion inhibiting properties of nicotine and to incorporate nicotine, a biodegradable and readily available natural product, into a PDMS coating to demonstrate the use of a natural product in a coating for marine applications. The corrosion inhibiting properties of nicotine was examined using potentiodynamic polarization scans, material characterization techniques such as scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction, quartz crystal microbalance and electrochemical impedance spectroscopy. Nicotine was determined to be an anodic corrosion inhibitor for mild steel immersed in simulated seawater with the ability to precipitate a protective calcium carbonate film. Electrochemical impedance spectroscopy was used to evaluate the performance of the developed nicotine incorporated coatings on mild steel immersed in simulated seawater over 21 days of immersion. The coatings with 2 wt.% of nicotine incorporated in the coating with a ratio of 1:30 of additional platinum catalyst to nicotine exhibited the best performance for intact coatings. This coating had the most favorable balance of the amount of nicotine and platinum catalyst of all the coatings evaluated. Overall, all nicotine incorporated coatings had a performance improvement when compared to the control PDMS coating. Of the nicotine incorporated coatings that were tested with an artificial pin-hole defect, the 2PDMS coating also exhibited the best performance with significant

  20. Vertical evolution of gravity wave spectra and the parameterization of associated wave drag

    NASA Astrophysics Data System (ADS)

    Medvedev, A. S.; Klaassen, G. P.

    1995-12-01

    Extensions of Weinstock's theory of nonlinear gravity waves and a parameterization of the related momentum deposition are developed. Our approach, which combines aspects of Hines' Doppler spreading theory with Weinstock's theory of nonlinear wave diffusion, treats the low-frequency part of the gravity wave spectrum as an additional background flow for higher-frequency waves. This technique allows one to calculate frequency shifting and wave amplitude damping produced by the interaction with this additional background wind. For a nearly monochromatic spectrum the parameterization formulae for wave drag coincide with those of Lindzen. It is shown that two processes should be distinguished: wave breaking due to instabilities and saturation due to nonlinear diffusionlike processes. The criteria for wave breaking and wave saturation in terms of wave spectra are derived. For a saturated spectrum the power spectral density's (PSD) dependence S(m) = AN2/m3 is obtained, where m is the vertical wavenumber and N is the Brunt-Väisäla frequency. Unlike Weinstock's original formulation, our coefficient of proportionality A is a slowly varying function of m and mean wind. For vertical wavelengths ranging from 10 km to 100 m and for typical wind shears, A varies from one half to one ninth. Calculations of spectral evolution with height as well as related profiles of wave drag are shown. These results reproduce vertical wavenumber spectral tail slopes which vary near the -3 value reported by observations. An explanation of these variations is given.

  1. A numerical study on the effects of wave-current-surge interactions on the height and propagation of sea surface waves in Charleston Harbor during Hurricane Hugo 1989

    NASA Astrophysics Data System (ADS)

    Liu, Huiqing; Xie, Lian

    2009-06-01

    The effects of wave-current interactions on ocean surface waves induced by Hurricane Hugo in and around the Charleston Harbor and its adjacent coastal waters are examined by using a three-dimensional (3D) wave-current coupled modeling system. The 3D storm surge modeling component of the coupled system is based on the Princeton Ocean Model (POM), the wave modeling component is based on the third generation wave model, Simulating WAves Nearshore (SWAN), and the inundation model is adopted from [Xie, L., Pietrafesa, L. J., Peng, M., 2004. Incorporation of a mass-conserving inundation scheme into a three-dimensional storm surge model. J. Coastal Res., 20, 1209-1223]. The results indicate that the change of water level associated with the storm surge is the primary cause for wave height changes due to wave-surge interaction. Meanwhile, waves propagating on top of surge cause a feedback effect on the surge height by modulating the surface wind stress and bottom stress. This effect is significant in shallow coastal waters, but relatively small in offshore deep waters. The influence of wave-current interaction on wave propagation is relatively insignificant, since waves generally propagate in the direction of the surface currents driven by winds. Wave-current interactions also affect the surface waves as a result of inundation and drying induced by the storm. Waves break as waters retreat in regions of drying, whereas waves are generated in flooded regions where no waves would have occurred without the flood water.

  2. Test particle method for incorporation of the kinetic effects into the envelope simulations of Raman backscattering

    SciTech Connect

    Hur, Min Sup; Suk, Hyyong

    2007-10-01

    A new test particle method is presented for self-consistent incorporation of the kinetic effects into the fluid three-wave model. One of the most important kinetic effects is the electron trapping and it has been found that the trapping affects significantly the behavior of Raman backscatter and Raman backward laser amplification. The conventional fluid three-wave model cannot reproduce the kinetic simulations in the trapping regime. The test particle scheme utilizes the same equations for the laser evolution as in the three-wave model. However, the plasma wave is treated by the envelope-kinetic equation, which consists of envelope evolution and the kinetic term. The core of the new scheme is employing test particles to compute the kinetic term self-consistently. The benchmarking results against the averaged particle-in-cell (aPIC) code show excellent agreements, and the computation speed gain over the aPIC is from 2 to 20 depending on parameters.

  3. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  4. Tackifier for addition polyimides

    NASA Technical Reports Server (NTRS)

    Butler, J. M.; St.clair, T. L.

    1980-01-01

    A modification to the addition polyimide, LaRC-160, was prepared to improve tack and drape and increase prepeg out-time. The essentially solventless, high viscosity laminating resin is synthesized from low cost liquid monomers. The modified version takes advantage of a reactive, liquid plasticizer which is used in place of solvent and helps solve a major problem of maintaining good prepeg tack and drape, or the ability of the prepeg to adhere to adjacent plies and conform to a desired shape during the lay up process. This alternate solventless approach allows both longer life of the polymer prepeg and the processing of low void laminates. This approach appears to be applicable to all addition polyimide systems.

  5. WaveAR: A software tool for calculating parameters for water waves with incident and reflected components

    NASA Astrophysics Data System (ADS)

    Landry, Blake J.; Hancock, Matthew J.; Mei, Chiang C.; García, Marcelo H.

    2012-09-01

    The ability to determine wave heights and phases along a spatial domain is vital to understanding a wide range of littoral processes. The software tool presented here employs established Stokes wave theory and sampling methods to calculate parameters for the incident and reflected components of a field of weakly nonlinear waves, monochromatic at first order in wave slope and propagating in one horizontal dimension. The software calculates wave parameters over an entire wave tank and accounts for reflection, weak nonlinearity, and a free second harmonic. Currently, no publicly available program has such functionality. The included MATLAB®-based open source code has also been compiled for Windows®, Mac® and Linux® operating systems. An additional companion program, VirtualWave, is included to generate virtual wave fields for WaveAR. Together, the programs serve as ideal analysis and teaching tools for laboratory water wave systems.

  6. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  7. Magnetic field waves at Uranus

    NASA Technical Reports Server (NTRS)

    Smith, Charles W.; Goldstein, Melvyn L.; Lepping, Ronald P.; Mish, William H.; Wong, Hung K.

    1994-01-01

    The research efforts funded by the Uranus Data Analysis Program (UDAP) grant to the Bartol Research Institute (BRI) involved the study of magnetic field waves associated with the Uranian bow shock. Upstream wave studies are motivated as a study of the physics of collisionless shocks. Collisionless shocks in plasmas are capable of 'reflecting' a fraction of the incoming thermal particle distribution and directing the resulting energetic particle motion back into the upstream region. Once within the upstream region, the backward streaming energetic particles convey information of the approaching shock to the supersonic flow. This particle population is responsible for the generation of upstream magnetic and electrostatic fluctuations known as 'upstream waves', for slowing the incoming wind prior to the formation of the shock ramp, and for heating of the upstream plasma. The waves produced at Uranus not only differed in several regards from the observations at other planetary bow shocks, but also gave new information regarding the nature of the reflected particle populations which were largely unmeasurable by the particle instruments. Four distinct magnetic field wave types were observed upstream of the Uranian bow shock: low-frequency Alfven or fast magnetosonic waves excited by energetic protons originating at or behind the bow shock; whistler wave bursts driven by gyrating ion distributions within the shock ramp; and two whistler wave types simultaneously observed upstream of the flanks of the shock and argued to arise from resonance with energetic electrons. In addition, observations of energetic particle distributions by the LECP experiment, thermal particle populations observed by the PLS experiment, and electron plasma oscillations recorded by the PWS experiment proved instrumental to this study and are included to some degree in the papers and presentations supported by this grant.

  8. Wave measurement and modeling in Chesapeake Bay

    NASA Astrophysics Data System (ADS)

    Lin, Weiqi; Sanford, Lawrence P.; Suttles, Steven E.

    2002-12-01

    Three recently measured wind and wave data sets in the northern part of Chesapeake Bay (CB) are presented. Two of the three data sets were collected in late 1995. The third one was collected in July of 1998. The analyzed wind and wave data show that waves were dominated by locally generated, fetch limited young wind seas. Significant wave heights were highly correlated to the local driving wind speeds and the response time of the waves to the winds was about 1 h. We also tested two very different numerical wave models, Simulation of WAves Nearshore (SWAN) and Great Lakes Environmental Research Laboratory (GLERL), to hind-cast the wave conditions against the data sets. Time series model-data comparisons made using SWAN and GLERL showed that both models behaved well in response to a suddenly changing wind. In general, both SWAN and GLERL over-predicted significant wave height; SWAN over-predicted more than GLERL did. SWAN had a larger scatter index and a smaller correlation coefficient for wave height than GLERL had. In addition, both models slightly under-predicted the peak period with a fairly large scatter and low correlation coefficient. SWAN predicted mean wave direction better than GLERL did. Directional wave spectral comparisons between SWAN predictions and the data support these statistical comparisons. The GLERL model was much more computationally efficient for wind wave forecasts in CB. SWAN and GLERL predicted different wave height field distributions for the same winds in deeper water areas of the Bay where data were not available, however. These differences are as yet unresolved.

  9. Subwavelength Fabry-Perot resonator: a pair of quantum dots incorporated with gold nanorod

    PubMed Central

    2012-01-01

    The two apexes of an elongated gold nanorod (GNR) irradiated by a plane wave are shown to be the hotspots at the longitudinal plasmon modes. This phenomenon implies that a pair of quantum dots (QDs) located at these apexes might be excited simultaneously if the excitation band of QDs coincides with one of these modes. Consequently, a coherent emission of the two emitters could happen subsequently. In the following coherent emission, these two-level emitters are simulated as two oscillating dipoles (bi-dipole) with some possible phase differences. Our results show that the maximum radiative and nonradiative powers of the bi-dipole occur at the longitudinal plasmon dipole, quadrupole, sextupole, and octupole modes of GNR. Moreover, the strongest emissions are induced by the in-phase bi-dipole coupled to the odd modes and the 180° out-of-phase one to the even modes, respectively. The excitation and emission behaviors of a pair of QDs incorporated with GNR demonstrate the possibility of using this structure as a subwavelength resonator of Fabry-Perot type. In addition, the correlation between these modes of the GNR and the dispersion relation of gold nanowire is also discussed. PMID:23031423

  10. Waves in Ice Forecasting for Arctic Operators

    NASA Astrophysics Data System (ADS)

    Dumont, D.; Williams, T.; Bennetts, L.

    2013-12-01

    Sea ice cover is becoming increasingly weak and fragmented during the summer in the Arctic Ocean. This presents new opportunities for offshore engineering activities and shipping routes. However, operational forecasting models do not include waves in the partially ice-covered ocean, or their impact on the ice cover, which severely compromises the safety of potential human activities in these regions. Wave-ice interactions are composed of two coupled processes. First, ice floes cause wave energy to attenuate. Second, wave motion imposes strains on the ice cover, which can fracture the ice into small floes. We have developed the first model that incorporates both wave attenuation and ice fracture. The model predicts the evolution of the wave spectrum in the ice-covered ocean and the floe size distribution in the initial 10s to 100s of kilometers of ice-covered ocean, where waves control the maximum floe size allowable. The model is currently being nested in areas of operational interest in a pan-Artic ice-ocean model.

  11. Incorporating seed orientation in brachytherapy implant reconstruction

    NASA Astrophysics Data System (ADS)

    Zhou, Yu; Jain, Ameet K.; Chirikjian, Gregory S.; Fichtinger, Gabor

    2006-03-01

    Intra-operative quality assurance and dosimetry optimization in prostate brachytherapy critically depends on the ability of discerning the locations of implanted seeds. Various methods exist for seed matching and reconstruction from multiple segmented C-arm images. Unfortunately, using three or more images makes the problem NP-hard, i.e. no polynomial-time algorithm can provably compute the complete matching. Typically, a statistical analysis of performance is considered sufficient. Hence it is of utmost importance to exploit all the available information in order to minimize the matching and reconstruction errors. Current algorithms use only the information about seed centers, disregarding the information about the orientations and length of seeds. While the latter has little dosimetric impact, it can positively contribute to improving seed matching rate and 3D implant reconstruction accuracy. It can also become critical information when hidden and spuriously segmented seeds need to be matched, where reliable and generic methods are not yet available. Expecting orientation information to be useful in reconstructing large and dense implants, we have developed a method which incorporates seed orientation information into our previously proposed reconstruction algorithm (MARSHAL). Simulation study shows that under normal segmentation errors, when considering seed orientations, implants of 80 to 140 seeds with the density of 2.0- 3.0 seeds/cc give an average matching rate >97% using three-image matching. It is higher than the matching rate of about 96% when considering only seed positions. This means that the information of seed orientations appears to be a valuable additive to fluoroscopy-based brachytherapy implant reconstruction.

  12. GRAVITATIONAL WAVES FROM STELLAR COLLAPSE

    SciTech Connect

    C. L. FRYER

    2001-01-01

    Stellar core-collapse plays an important role in nearly all facets of astronomy: cosmology (as standard candles), formation of compact objects, nucleosynthesis and energy deposition in galaxies. In addition, they release energy in powerful explosions of light over a range of energies, neutrinos, and the subject of this meeting, gravitational waves. Because of this broad range of importance, astronomers have discovered a number of constraints which can be used to help them understand the importance of stellar core-collapse as gravitational wave sources.

  13. A joint method to retrieve directional ocean wave spectra from SAR and wave spectrometer data

    NASA Astrophysics Data System (ADS)

    Ren, Lin; Yang, Jingsong; Zheng, Gang; Wang, Juan

    2016-07-01

    This paper proposes a joint method to simultaneously retrieve wave spectra at different scales from spaceborne Synthetic Aperture Radar (SAR) and wave spectrometer data. The method combines the output from the two different sensors to overcome retrieval limitations that occur in some sea states. The wave spectrometer sensitivity coefficient is estimated using an effective significant wave height (SWH), which is an average of SAR-derived and wave spectrometer-derived SWH. This averaging extends the area of the sea surface sampled by the nadir beam of the wave spectrometer to improve the accuracy of the estimated sensitivity coefficient in inhomogeneous sea states. Wave spectra are then retrieved from SAR data using wave spectrometer-derived spectra as first guess spectra to complement the short waves lost in SAR data retrieval. In addition, the problem of 180° ambiguity in retrieved spectra is overcome using SAR imaginary cross spectra. Simulated data were used to validate the joint method. The simulations demonstrated that retrieved wave parameters, including SWH, peak wave length (PWL), and peak wave direction (PWD), agree well with reference parameters. Collocated data from ENVISAT advanced SAR (ASAR), the airborne wave spectrometer STORM, the PHAROS buoy, and the European Centre for Medium-Range Weather Forecasting (ECMWF) were then used to verify the proposed method. Wave parameters retrieved from STORM and two ASAR images were compared to buoy and ECMWF wave data. Most of the retrieved parameters were comparable to reference parameters. The results of this study show that the proposed joint retrieval method could be a valuable complement to traditional methods used to retrieve directional ocean wave spectra, particularly in inhomogeneous sea states.

  14. Optofluidics incorporating actively controlled micro- and nano-particles

    PubMed Central

    Kayani, Aminuddin A.; Khoshmanesh, Khashayar; Ward, Stephanie A.; Mitchell, Arnan; Kalantar-zadeh, Kourosh

    2012-01-01

    The advent of optofluidic systems incorporating suspended particles has resulted in the emergence of novel applications. Such systems operate based on the fact that suspended particles can be manipulated using well-appointed active forces, and their motions, locations and local concentrations can be controlled. These forces can be exerted on both individual and clusters of particles. Having the capability to manipulate suspended particles gives users the ability for tuning the physical and, to some extent, the chemical properties of the suspension media, which addresses the needs of various advanced optofluidic systems. Additionally, the incorporation of particles results in the realization of novel optofluidic solutions used for creating optical components and sensing platforms. In this review, we present different types of active forces that are used for particle manipulations and the resulting optofluidic systems incorporating them. These systems include optical components, optofluidic detection and analysis platforms, plasmonics and Raman systems, thermal and energy related systems, and platforms specifically incorporating biological particles. We conclude the review with a discussion of future perspectives, which are expected to further advance this rapidly growing field. PMID:23864925

  15. Inductance of rf-wave-heated plasmas.

    PubMed

    Farshi, E; Todo, Y

    2003-03-14

    The inductance of rf-wave-heated plasmas is derived. This inductance represents the inductance of fast electrons located in a plateau during their acceleration due to electric field or deceleration due to collisions and electric field. This inductance has been calculated for small electric fields from the two-dimensional Fokker-Planck equation as the flux crossing the surface of critical energy mv(2)(ph)/2 in the velocity space. The new expression may be important for radio-frequency current drive ramp-up, current drive efficiency, current profile control, and so on in tokamaks. This inductance may be incorporated into transport codes that study plasma heating by rf waves.

  16. P-Wave Electron-Hydrogen Scattering

    NASA Technical Reports Server (NTRS)

    Bhtia, Anand

    2012-01-01

    A variational wave function incorporating short range correlations via Hylleraas type functions plus long-range polarization terms of the polarized orbital type but with smooth cut-off factors has been used to calculate P-wave phase shifts for electron-hydrogen scattering. This approach gives the direct r(exp -4) potential and a non-local optical potential which is definite. The resulting phase shifts have rigorous lower bounds and the convergence is much faster than those obtained without the modification of the target function. Final results will be presented at the conference.

  17. A Simple Wave Driver

    ERIC Educational Resources Information Center

    Temiz, Burak Kagan; Yavuz, Ahmet

    2015-01-01

    This study was done to develop a simple and inexpensive wave driver that can be used in experiments on string waves. The wave driver was made using a battery-operated toy car, and the apparatus can be used to produce string waves at a fixed frequency. The working principle of the apparatus is as follows: shortly after the car is turned on, the…

  18. Incorporating Spatial Ability Instruction in Teacher Preparation

    ERIC Educational Resources Information Center

    Sundberg, Sue E.; Goodman, Terry A.

    2005-01-01

    This article provides a picture of the learning environment that is created for the preservice mathematics teacher and how development of spatial abilities can be incorporated into courses for these students. (Contains 3 figures.)

  19. 1. Building #3, original structure and first addition, north side, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Building #3, original structure and first addition, north side, looking south. Photo shows (from left) the original 1911 structure, the 1939 infill addition, and the 1934 structure. - S. W. Shattuck Chemical Company, Incorporated, Building No. 3, 1805 South Bannock Street, Denver, Denver County, CO

  20. Teleseismic S wave microseisms.

    PubMed

    Nishida, Kiwamu; Takagi, Ryota

    2016-08-26

    Although observations of microseisms excited by ocean swells were firmly established in the 1940s, the source locations remain difficult to track. Delineation of the source locations and energy partition of the seismic wave components are key to understanding the excitation mechanisms. Using a seismic array in Japan, we observed both P and S wave microseisms excited by a severe distant storm in the Atlantic Ocean. Although nonlinear forcing of an ocean swell with a one-dimensional Earth model can explain P waves and vertically polarized S waves (SV waves), it cannot explain horizontally polarized S waves (SH waves). The precise source locations may provide a new catalog for exploring Earth's interior.

  1. Planetary plasma waves

    NASA Technical Reports Server (NTRS)

    Gurnett, Donald A.

    1993-01-01

    The primary types of plasma waves observed in the vicinity of the planets Venus, Mars, Earth, Jupiter, Saturn, Uranus, and Neptune are described. The observations are organized according to the various types of plasma waves observed, ordered according to decreasing distance from the planet, starting from the sunward side of the planet, and ending in the region near the closest approach. The plasma waves observed include: electron plasma oscillations and ion acoustic waves; trapped continuum radiation; electron cyclotron and upper hybrid waves; whistler-mode emissions; electrostatic ion cyclotron waves; and electromagnetic ion cyclotron waves.

  2. Wave energy converter effects on wave propagation: A sensitivity study in Monterey Bay, CA

    NASA Astrophysics Data System (ADS)

    Chang, G.; Jones, C. A.; Roberts, J.; Magalen, J.; Ruehl, K.; Chartrand, C.

    2014-12-01

    The development of renewable offshore energy in the United States is growing rapidly and wave energy is one of the largest resources currently being evaluated. The deployment of wave energy converter (WEC) arrays required to harness this resource could feasibly number in the hundreds of individual devices. The WEC arrays have the potential to alter nearshore wave propagation and circulation patterns and ecosystem processes. As the industry progresses from pilot- to commercial-scale it is important to understand and quantify the effects of WECs on the natural nearshore processes that support a local, healthy ecosystem. To help accelerate the realization of commercial-scale wave power, predictive modeling tools have been developed and utilized to evaluate the likelihood of environmental impact. At present, direct measurements of the effects of different types of WEC arrays on nearshore wave propagation are not available; therefore wave model simulations provide the groundwork for investigations of the sensitivity of model results to prescribed WEC characteristics over a range of anticipated wave conditions. The present study incorporates a modified version of an industry standard wave modeling tool, SWAN (Simulating WAves Nearshore), to simulate wave propagation through a hypothetical WEC array deployment site on the California coast. The modified SWAN, referred to as SNL-SWAN, incorporates device-specific WEC power take-off characteristics to more accurately evaluate a WEC device's effects on wave propagation. The primary objectives were to investigate the effects of a range of WEC devices and device and array characteristics (e.g., device spacing, number of WECs in an array) on nearshore wave propagation using SNL-SWAN model simulations. Results showed that significant wave height was most sensitive to variations in WEC device type and size and the number of WEC devices in an array. Locations in the lee centerline of the arrays in each modeled scenario showed the

  3. 49 CFR 572.80 - Incorporated materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the materials may be obtained from Rowley-Scher... 49 Transportation 7 2010-10-01 2010-10-01 false Incorporated materials. 572.80 Section 572.80... Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth...

  4. 49 CFR 572.80 - Incorporated materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the materials may be obtained from Rowley-Scher... 49 Transportation 7 2013-10-01 2013-10-01 false Incorporated materials. 572.80 Section 572.80... Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth...

  5. 49 CFR 572.80 - Incorporated materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the materials may be obtained from Rowley-Scher... 49 Transportation 7 2011-10-01 2011-10-01 false Incorporated materials. 572.80 Section 572.80... Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth...

  6. 49 CFR 572.80 - Incorporated materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the materials may be obtained from Rowley-Scher... 49 Transportation 7 2014-10-01 2014-10-01 false Incorporated materials. 572.80 Section 572.80... Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth...

  7. 49 CFR 572.80 - Incorporated materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the materials may be obtained from Rowley-Scher... 49 Transportation 7 2012-10-01 2012-10-01 false Incorporated materials. 572.80 Section 572.80... Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth...

  8. Performance Boosting Additive

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

  9. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  10. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  11. Sarks as additional fermions

    NASA Astrophysics Data System (ADS)

    Agrawal, Jyoti; Frampton, Paul H.; Jack Ng, Y.; Nishino, Hitoshi; Yasuda, Osamu

    1991-03-01

    An extension of the standard model is proposed. The gauge group is SU(2) X ⊗ SU(3) C ⊗ SU(2) S ⊗ U(1) Q, where all gauge symmetries are unbroken. The colour and electric charge are combined with SU(2) S which becomes strongly coupled at approximately 500 GeV and binds preons to form fermionic and vector bound states. The usual quarks and leptons are singlets under SU(2) X but additional fermions, called sarks. transform under it and the electroweak group. The present model explains why no more than three light quark-lepton families can exist. Neutral sark baryons, called narks, are candidates for the cosmological dark matter having the characteristics designed for WIMPS. Further phenomenological implications of sarks are analyzed i including electron-positron annihilation. Z 0 decay, flavor-changing neutral currents. baryon-number non-conservation, sarkonium and the neutron electric dipole moment.

  12. Human capital, gender, and labor force incorporation: The case of immigrants from the Former Soviet Union.

    PubMed

    Logan, John R; Rivera Drew, Julia A

    2011-02-01

    Women immigrating to the United States from the Former Soviet Union (FSU) were expected to incorporate seamlessly into the US labor force because of their strong educational and professional backgrounds. Using 2000 Census data, we find that FSU women were less successful than both FSU men and other non-Hispanic white female immigrants. After controlling for other factors, FSU women were more likely to rely on public assistance and less likely to be employed. If employed, they worked in less prestigious occupations and earned much less. These findings draw attention to the particular difficulties of incorporation of this wave of relatively advantaged immigrants.

  13. Human capital, gender, and labor force incorporation: The case of immigrants from the Former Soviet Union

    PubMed Central

    Logan, John R.; Rivera Drew, Julia A.

    2013-01-01

    Women immigrating to the United States from the Former Soviet Union (FSU) were expected to incorporate seamlessly into the US labor force because of their strong educational and professional backgrounds. Using 2000 Census data, we find that FSU women were less successful than both FSU men and other non-Hispanic white female immigrants. After controlling for other factors, FSU women were more likely to rely on public assistance and less likely to be employed. If employed, they worked in less prestigious occupations and earned much less. These findings draw attention to the particular difficulties of incorporation of this wave of relatively advantaged immigrants. PMID:24009398

  14. Gravity wave transmission diagram

    NASA Astrophysics Data System (ADS)

    Tomikawa, Yoshihiro

    2016-07-01

    A possibility of gravity wave propagation from a source region to the airglow layer around the mesopause has been discussed based on the gravity wave blocking diagram taking into account the critical level filtering alone. This paper proposes a new gravity wave transmission diagram in which both the critical level filtering and turning level reflection of gravity waves are considered. It shows a significantly different distribution of gravity wave transmissivity from the blocking diagram.

  15. The wave-induced sediment responses in the subaquous Yellow River delta, China: new insights into seabed inhomogeneity

    NASA Astrophysics Data System (ADS)

    Liu, X.; Jia, Y.; Zheng, J.; Shan, H.

    2014-12-01

    This paper presents the results of an experimental study of the wave-induced sediment responses in the subaqueous Yellow River delta. The pore pressure, sediment particle size composition, microstructure, physical and mechanical properties at different depths inside the seabed were observed during the experimental process under the weight of the soil and under the action of waves of different heights. The results showed that wave-induced sediment responses significantly controlled the occurrence and evolution of inhomogeneity in the strength and sediment distribution of a uniform-originated silty seabed. The variations in the strength, composition and structure of during the wave-sediment interaction processes are closely related to the pore water seepage inside the seabed. The driving machanism can be devided into three modes: transient seepage caused by pore pressure oscillation, seepage failure caused by pore pressure accumulation and liquefaction failure caused by pore pressure accumulation, during which the latter is the main cause of vertical transport of pore water carrying a large amount of fine particles inside the seabed of the subaqueous Yellow River delta. The array of features observed in these experiments can be incorporated into a new model of seabed stratification in uniform-originated silty sediments during wave-sediment interaction. In addition, the implications of this model for traditional sedimentology are explored from a sediment dynamic perspective.

  16. Photoelectron wave function in photoionization: plane wave or Coulomb wave?

    PubMed

    Gozem, Samer; Gunina, Anastasia O; Ichino, Takatoshi; Osborn, David L; Stanton, John F; Krylov, Anna I

    2015-11-19

    The calculation of absolute total cross sections requires accurate wave functions of the photoelectron and of the initial and final states of the system. The essential information contained in the latter two can be condensed into a Dyson orbital. We employ correlated Dyson orbitals and test approximate treatments of the photoelectron wave function, that is, plane and Coulomb waves, by comparing computed and experimental photoionization and photodetachment spectra. We find that in anions, a plane wave treatment of the photoelectron provides a good description of photodetachment spectra. For photoionization of neutral atoms or molecules with one heavy atom, the photoelectron wave function must be treated as a Coulomb wave to account for the interaction of the photoelectron with the +1 charge of the ionized core. For larger molecules, the best agreement with experiment is often achieved by using a Coulomb wave with a partial (effective) charge smaller than unity. This likely derives from the fact that the effective charge at the centroid of the Dyson orbital, which serves as the origin of the spherical wave expansion, is smaller than the total charge of a polyatomic cation. The results suggest that accurate molecular photoionization cross sections can be computed with a modified central potential model that accounts for the nonspherical charge distribution of the core by adjusting the charge in the center of the expansion.

  17. Photoelectron wave function in photoionization: plane wave or Coulomb wave?

    PubMed

    Gozem, Samer; Gunina, Anastasia O; Ichino, Takatoshi; Osborn, David L; Stanton, John F; Krylov, Anna I

    2015-11-19

    The calculation of absolute total cross sections requires accurate wave functions of the photoelectron and of the initial and final states of the system. The essential information contained in the latter two can be condensed into a Dyson orbital. We employ correlated Dyson orbitals and test approximate treatments of the photoelectron wave function, that is, plane and Coulomb waves, by comparing computed and experimental photoionization and photodetachment spectra. We find that in anions, a plane wave treatment of the photoelectron provides a good description of photodetachment spectra. For photoionization of neutral atoms or molecules with one heavy atom, the photoelectron wave function must be treated as a Coulomb wave to account for the interaction of the photoelectron with the +1 charge of the ionized core. For larger molecules, the best agreement with experiment is often achieved by using a Coulomb wave with a partial (effective) charge smaller than unity. This likely derives from the fact that the effective charge at the centroid of the Dyson orbital, which serves as the origin of the spherical wave expansion, is smaller than the total charge of a polyatomic cation. The results suggest that accurate molecular photoionization cross sections can be computed with a modified central potential model that accounts for the nonspherical charge distribution of the core by adjusting the charge in the center of the expansion. PMID:26509428

  18. Spectral-element Seismic Wave Propagation on CUDA/OpenCL Hardware Accelerators

    NASA Astrophysics Data System (ADS)

    Peter, D. B.; Videau, B.; Pouget, K.; Komatitsch, D.

    2015-12-01

    Seismic wave propagation codes are essential tools to investigate a variety of wave phenomena in the Earth. Furthermore, they can now be used for seismic full-waveform inversions in regional- and global-scale adjoint tomography. Although these seismic wave propagation solvers are crucial ingredients to improve the resolution of tomographic images to answer important questions about the nature of Earth's internal processes and subsurface structure, their practical application is often limited due to high computational costs. They thus need high-performance computing (HPC) facilities to improving the current state of knowledge. At present, numerous large HPC systems embed many-core architectures such as graphics processing units (GPUs) to enhance numerical performance. Such hardware accelerators can be programmed using either the CUDA programming environment or the OpenCL language standard. CUDA software development targets NVIDIA graphic cards while OpenCL was adopted by additional hardware accelerators, like e.g. AMD graphic cards, ARM-based processors as well as Intel Xeon Phi coprocessors. For seismic wave propagation simulations using the open-source spectral-element code package SPECFEM3D_GLOBE, we incorporated an automatic source-to-source code generation tool (BOAST) which allows us to use meta-programming of all computational kernels for forward and adjoint runs. Using our BOAST kernels, we generate optimized source code for both CUDA and OpenCL languages within the source code package. Thus, seismic wave simulations are able now to fully utilize CUDA and OpenCL hardware accelerators. We show benchmarks of forward seismic wave propagation simulations using SPECFEM3D_GLOBE on CUDA/OpenCL GPUs, validating results and comparing performances for different simulations and hardware usages.

  19. Global MHD modeling of resonant ULF waves: Simulations with and without a plasmasphere

    NASA Astrophysics Data System (ADS)

    Claudepierre, S. G.; Toffoletto, F. R.; Wiltberger, M.

    2016-01-01

    We investigate the plasmaspheric influence on the resonant mode coupling of magnetospheric ultralow frequency (ULF) waves using the Lyon-Fedder-Mobarry (LFM) global magnetohydrodynamic (MHD) model. We present results from two different versions of the model, both driven by the same solar wind conditions: one version that contains a plasmasphere (the LFM coupled to the Rice Convection Model, where the Gallagher plasmasphere model is also included) and another that does not (the stand-alone LFM). We find that the inclusion of a cold, dense plasmasphere has a significant impact on the nature of the simulated ULF waves. For example, the inclusion of a plasmasphere leads to a deeper (more earthward) penetration of the compressional (azimuthal) electric field fluctuations, due to a shift in the location of the wave turning points. Consequently, the locations where the compressional electric field oscillations resonantly couple their energy into local toroidal mode field line resonances also shift earthward. We also find, in both simulations, that higher-frequency compressional (azimuthal) electric field oscillations penetrate deeper than lower frequency oscillations. In addition, the compressional wave mode structure in the simulations is consistent with a radial standing wave oscillation pattern, characteristic of a resonant waveguide. The incorporation of a plasmasphere into the LFM global MHD model represents an advance in the state of the art in regard to ULF wave modeling with such simulations. We offer a brief discussion of the implications for radiation belt modeling techniques that use the electric and magnetic field outputs from global MHD simulations to drive particle dynamics.

  20. Instability of Wave Trains and Wave Probabilities

    NASA Astrophysics Data System (ADS)

    Babanin, Alexander

    2013-04-01

    Centre for Ocean Engineering, Science and Technology, Swinburne University of Technology, Melbourne, Australia, ababanin@swin.edu.au Design criteria in ocean engineering, whether this is one in 50 years or one in 5000 years event, are hardly ever based on measurements, and rather on statistical distributions of relevant metocean properties. Of utmost interest is the tail of distribution, that is rare events such as the highest waves with low probability. Engineers have long since realised that the superposition of linear waves with narrow-banded spectrum as depicted by the Rayleigh distribution underestimates the probability of extreme wave heights and crests, which is a critical shortcoming as far as the engineering design is concerned. Ongoing theoretical and experimental efforts have been under way for decades to address this issue. Typical approach is the treating all possible waves in the ocean or at a particular location as a single ensemble for which some comprehensive solution can be obtained. The oceanographic knowledge, however, now indicates that no single and united comprehensive solution is available. We would expect the probability distributions of wave height to depend on a) whether the waves are at the spectral peak or at the tail; b) on wave spectrum and mean steepness in the wave field; c) on the directional distribution of the peak waves; d) on whether the waves are in deep water, in intermediate depth or in shallow water; e) on wave breaking; f) on the wind, particularly if it is very strong, and on the currents if they have suitable horizontal gradients. Probability distributions in the different circumstances according to these groups of conditions should be different, and by combining them together the inevitable scatter is introduced. The scatter and the accuracy will not improve by increasing the bulk data quality and quantity, and it hides the actual distribution of extremes. The groups have to be separated and their probability

  1. Effects of simulated heat waves on ApoE-/- mice.

    PubMed

    Wang, Chunling; Zhang, Shuyu; Tian, Ying; Wang, Baojian; Shen, Shuanghe

    2014-02-01

    The effects of simulated heat waves on body weight, body temperature, and biomarkers of cardiac function in ApoE-/- mice were investigated. Heat waves were simulated in a meteorological environment simulation chamber according to data from a heat wave that occurred in July 2001 in Nanjing, China. Eighteen ApoE-/- mice were divided into control group, heat wave group, and heat wave BH4 group. Mice in the heat wave and BH4 groups were exposed to simulated heat waves in the simulation chamber. Mice in BH4 group were treated with gastric lavage with BH4 2 h prior to heat wave exposure. Results showed that the heat waves did not significantly affect body weight or ET-1 levels. However, mice in the heat wave group had significantly higher rectal temperature and NO level and lower SOD activity compared with mice in the control group (p < 0.01), indicating that heat wave had negative effects on cardiac function in ApoE-/- mice. Gastric lavage with BH4 prior to heat wave exposure significantly reduced heat wave-induced increases in rectal temperature and decreases in SOD activity. Additionally, pretreatment with BH4 further increased NO level in plasma. Collectively, these beneficial effects demonstrate that BH4 may potentially mitigate the risk of coronary heart disease in mice under heat wave exposure. These results may be useful when studying the effects of heat waves on humans. PMID:24477215

  2. Effects of simulated heat waves on ApoE-/- mice.

    PubMed

    Wang, Chunling; Zhang, Shuyu; Tian, Ying; Wang, Baojian; Shen, Shuanghe

    2014-02-01

    The effects of simulated heat waves on body weight, body temperature, and biomarkers of cardiac function in ApoE-/- mice were investigated. Heat waves were simulated in a meteorological environment simulation chamber according to data from a heat wave that occurred in July 2001 in Nanjing, China. Eighteen ApoE-/- mice were divided into control group, heat wave group, and heat wave BH4 group. Mice in the heat wave and BH4 groups were exposed to simulated heat waves in the simulation chamber. Mice in BH4 group were treated with gastric lavage with BH4 2 h prior to heat wave exposure. Results showed that the heat waves did not significantly affect body weight or ET-1 levels. However, mice in the heat wave group had significantly higher rectal temperature and NO level and lower SOD activity compared with mice in the control group (p < 0.01), indicating that heat wave had negative effects on cardiac function in ApoE-/- mice. Gastric lavage with BH4 prior to heat wave exposure significantly reduced heat wave-induced increases in rectal temperature and decreases in SOD activity. Additionally, pretreatment with BH4 further increased NO level in plasma. Collectively, these beneficial effects demonstrate that BH4 may potentially mitigate the risk of coronary heart disease in mice under heat wave exposure. These results may be useful when studying the effects of heat waves on humans.

  3. Particle current on flexible surfaces excited by harmonic waves.

    PubMed

    Verma, Neeta; DasGupta, Anirvan

    2013-11-01

    In this paper, a study on the directed particle current on flexible surfaces excited by a harmonic wave is reported. The proposed theory considers three different models for the kinematics of the surface, namely the Euler-Bernoulli, Timoshenko, and Rayleigh surface wave models. The particle-surface interaction terms in the theory incorporate Coulomb friction and inelastic collision between the particle and the surface. Three possible phases of motion, namely sticking, sliding, and jumping, are considered, and the phase transition boundaries are estimated analytically for a general surface model. The effect of various parameters on the particle current and certain statistical features of the particle motion are then studied numerically. Remarkably, the particle current spectra exhibit, in addition to resonance modes, antiresonance and secondary resonance modes and transversal zero crossings. These features have interesting implications for the particle dynamics in terms of dynamic jamming states and particle eddies, which are pointed out. Under certain restricted conditions, averaging calculations are also performed and compared with the corresponding numerical simulations. PMID:24329339

  4. Numerical Study of Stratified Charge Combustion in Wave Rotors

    NASA Technical Reports Server (NTRS)

    Nalim, M. Razi

    1997-01-01

    A wave rotor may be used as a pressure-gain combustor effecting non-steady flow, and intermittent, confined combustion to enhance gas turbine engine performance. It will be more compact and probably lighter than an equivalent pressure-exchange wave rotor, yet will have similar thermodynamic and mechanical characteristics. Because the allowable turbine blade temperature limits overall fuel/air ratio to sub-flammable values, premixed stratification techniques are necessary to burn hydrocarbon fuels in small engines with compressor discharge temperature well below autoignition conditions. One-dimensional, unsteady numerical simulations of stratified-charge combustion are performed using an eddy-diffusivity turbulence model and a simple reaction model incorporating a flammability limit temperature. For good combustion efficiency, a stratification strategy is developed which concentrates fuel at the leading and trailing edges of the inlet port. Rotor and exhaust temperature profiles and performance predictions are presented at three representative operating conditions of the engine: full design load, 40% load, and idle. The results indicate that peak local gas temperatures will result in excessive temperatures within the rotor housing unless additional cooling methods are used. The rotor itself will have acceptable temperatures, but the pattern factor presented to the turbine may be of concern, depending on exhaust duct design and duct-rotor interaction.

  5. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes. PMID:27679822

  6. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.

  7. Ion Bernstein wave heating research

    SciTech Connect

    Ono, Masayuki.

    1992-03-01

    Ion Bernstein wave heating (IBWH) utilizes the ion Bernstein wave (IBW), a hot plasma wave, to carry the radio frequency (rf) power to heat tokamak reactor core. Earlier wave accessibility studies have shown that this finite-Larmor-radius (FLR) mode should penetrate into a hot dense reactor plasma core without significant attenuation. Moreover, the IBW's low phase velocity ({omega}/k{sub {perpendicular}} {approx} V{sub Ti} {much lt} V{sub {alpha}}) greatly reduces the otherwise serious wave absorption by the 3.5 MeV fusion {alpha}-particles. In addition, the property of IBW's that k{sub {perpendicular}} {rho}{sub i} {approx} 1 makes localized bulk ion heating possible at the ion cyclotron harmonic layers. Such bulk ion heating can prove useful in optimizing fusion reactivity. In another vein, with proper selection of parameters, IBW's can be made subject to strong localized electron Landau damping near the major ion cyclotron harmonic resonance layers. This property can be useful, for example, for rf current drive in the reactor plasma core. This paper discusses this research.

  8. Ion Bernstein wave heating research

    SciTech Connect

    Ono, Masayuki

    1992-03-01

    Ion Bernstein wave heating (IBWH) utilizes the ion Bernstein wave (IBW), a hot plasma wave, to carry the radio frequency (rf) power to heat tokamak reactor core. Earlier wave accessibility studies have shown that this finite-Larmor-radius (FLR) mode should penetrate into a hot dense reactor plasma core without significant attenuation. Moreover, the IBW`s low phase velocity ({omega}/k{sub {perpendicular}} {approx} V{sub Ti} {much_lt} V{sub {alpha}}) greatly reduces the otherwise serious wave absorption by the 3.5 MeV fusion {alpha}-particles. In addition, the property of IBW`s that k{sub {perpendicular}} {rho}{sub i} {approx} 1 makes localized bulk ion heating possible at the ion cyclotron harmonic layers. Such bulk ion heating can prove useful in optimizing fusion reactivity. In another vein, with proper selection of parameters, IBW`s can be made subject to strong localized electron Landau damping near the major ion cyclotron harmonic resonance layers. This property can be useful, for example, for rf current drive in the reactor plasma core. This paper discusses this research.

  9. Wave energy and wave-induced flow reduction by full-scale model Posidonia oceanica seagrass

    NASA Astrophysics Data System (ADS)

    Manca, E.; Cáceres, I.; Alsina, J. M.; Stratigaki, V.; Townend, I.; Amos, C. L.

    2012-12-01

    This paper presents results from experiments in a large flume on wave and flow attenuation by a full-scale artificial Posidonia oceanica seagrass meadow in shallow water. Wave height and in-canopy wave-induced flows were reduced by the meadow under all tested regular and irregular wave conditions, and were affected by seagrass density, submergence and distance from the leading edge. The energy of irregular waves was reduced at all components of the spectra, but reduction was greater at the peak spectral frequency. Energy dissipation factors were largest for waves with small orbital amplitudes and at low wave Reynolds numbers. An empirical model, commonly applied to predict friction factors by rough beds, proved applicable to the P. oceanica bed. However at the lowest Reynolds numbers, under irregular waves, the data deviated significantly from the model. In addition, the wave-induced flow dissipation in the lower canopy increased with increasing wave orbital amplitude and increasing density of the mimics. The analysis of the wave-induced flow spectra confirm this trend: the reduction of flow was greatest at the longer period component of the spectra. Finally, we discuss the implications of these findings for sediment dynamics and the role of P. oceanica beds in protecting the shore from erosion.

  10. Quantifying wave-breaking dissipation using nonlinear phase-resolved wave-field simulations with a phenomenological-based wave breaking model

    NASA Astrophysics Data System (ADS)

    Qi, Yusheng; Yue, Dick

    2015-11-01

    We use direct nonlinear phase-resolved simulations based on a High-Order Spectral (HOS) method (Dommermuth & Yue 1987) to understand and quantify wave-breaking dissipation in the evolution of general irregular short-crested wave-fields. We achieve this by incorporating a robust phenomenological-based wave breaking model in HOS simulations to account for energy dissipation. This model can automatically simulate the onset of wave breaking, and the simulated wave-breaking dissipation strength differentiates corresponding to different wave breaking type (such as spilling or plunging breaking waves). The efficacy of this model is confirmed by direct comparisons against measurements for the energy loss in 2D and 3D breaking events. By comparing simulated wave-fields with and without the dissipation model in HOS, we obtain the dissipation field, which provides the times, locations and intensity of wave breaking events. From the dissipation field we further calculate the distribution of total length of breaking wave front per unit surface area per unit increment of breaking velocity (Phillips 1985), and obtain qualitative agreement with Phillips theoretical power-law.

  11. Wave-propagation formulation of seismic response of multistory buildings

    USGS Publications Warehouse

    Safak, E.

    1999-01-01

    This paper presents a discrete-time wave-propagation method to calculate the seismic response of multistory buildings, founded on layered soil media and subjected to vertically propagating shear waves. Buildings are modeled as an extension of the layered soil media by considering each story as another layer in the wave-propagation path. The seismic response is expressed in terms of wave travel times between the layers and wave reflection and transmission coefficients at layer interfaces. The method accounts for the filtering effects of the concentrated foundation and floor masses. Compared with commonly used vibration formulation, the wave-propagation formulation provides several advantages, including simplicity, improved accuracy, better representation of damping, the ability to incorporate the soil layers under the foundation, and providing better tools for identification and damage detection from seismic records. Examples are presented to show the versatility and the superiority of the method.

  12. Longitudinal nonlinear wave propagation through soft tissue.

    PubMed

    Valdez, M; Balachandran, B

    2013-04-01

    In this paper, wave propagation through soft tissue is investigated. A primary aim of this investigation is to gain a fundamental understanding of the influence of soft tissue nonlinear material properties on the propagation characteristics of stress waves generated by transient loadings. Here, for computational modeling purposes, the soft tissue is modeled as a nonlinear visco-hyperelastic material, the geometry is assumed to be one-dimensional rod geometry, and uniaxial propagation of longitudinal waves is considered. By using the linearized model, a basic understanding of the characteristics of wave propagation is developed through the dispersion relation and in terms of the propagation speed and attenuation. In addition, it is illustrated as to how the linear system can be used to predict brain tissue material parameters through the use of available experimental ultrasonic attenuation curves. Furthermore, frequency thresholds for wave propagation along internal structures, such as axons in the white matter of the brain, are obtained through the linear analysis. With the nonlinear material model, the authors analyze cases in which one of the ends of the rods is fixed and the other end is subjected to a loading. Two variants of the nonlinear model are analyzed and the associated predictions are compared with the predictions of the corresponding linear model. The numerical results illustrate that one of the imprints of the nonlinearity on the wave propagation phenomenon is the steepening of the wave front, leading to jump-like variations in the stress wave profiles. This phenomenon is a consequence of the dependence of the local wave speed on the local deformation of the material. As per the predictions of the nonlinear material model, compressive waves in the structure travel faster than tensile waves. Furthermore, it is found that wave pulses with large amplitudes and small elapsed times are attenuated over shorter spans. This feature is due to the elevated

  13. A shear wave ground surface vibration technique for the detection of buried pipes

    NASA Astrophysics Data System (ADS)

    Muggleton, J. M.; Papandreou, B.

    2014-07-01

    A major UK initiative, entitled 'Mapping the Underworld' aims to develop and prove the efficacy of a multi-sensor device for accurate remote buried utility service detection, location and, where possible, identification. One of the technologies to be incorporated in the device is low-frequency vibro-acoustics; the application of this technology for detecting buried infrastructure, in particular pipes, is currently being investigated. Here, a shear wave ground vibration technique for detecting buried pipes is described. For this technique, shear waves are generated at the ground surface, and the resulting ground surface vibrations measured. Time-extended signals are employed to generate the illuminating wave. Generalized cross-correlation functions between the measured ground velocities and a reference measurement adjacent to the excitation are calculated and summed using a stacking method to generate a cross-sectional image of the ground. To mitigate the effects of other potential sources of vibration in the vicinity, the excitation signal can be used as an additional reference when calculating the cross-correlation functions. Measurements have been made at two live test sites to detect a range of buried pipes. Successful detection of the pipes was achieved, with the use of the additional reference signal proving beneficial in the noisier of the two environments.

  14. Electron acceleration by inertial Alfven waves

    SciTech Connect

    Thompson, B.J.; Lysak, R.L.

    1996-03-01

    Alfven waves reflected by the ionosphere and by inhomogeneities in the Alfven speed can develop an oscillating parallel electric field when electron inertial effects are included. These waves, which have wavelengths of the order of an Earth radius, can develop a coherent structure spanning distances of several Earth radii along geomagnetic field lines. This system has characteristic frequencies in the range of 1 Hz and can exhibit electric fields capable of accelerating electrons in several senses: via Landua resonance, bounce or transit time resonance as discussed by Andre and Eliasson or through the effective potential drop which appears when the transit time of the electrons is much smaller than the wave period, so that the electric fields appear effectively static. A time-dependent model of wave propagation is developed which represents inertial Alfven wave propagation along auroral field lines. The disturbance is modeled as it travels earthward, experiences partial reflections in regions of rapid variation, and finally reflects off a conducting ionosphere to continue propagating antiearthward. The wave experiences partial trapping by the ionospheric and the Alfven speed peaks discussed earlier by Polyakov and Rapoport and Trakhtengerts and Feldstein and later by Lysak. Results of the wave simulation and an accompanying test particle simulation are presented, which indicate that inertial Alfven waves are a possible mechanism for generating electron conic distributions and field-aligned particle precipitation. The model incorporates conservation of energy by allowing electrons to affect the wave via Landau damping, which appears to enhance the effect of the interactions which heat electron populations. 22 refs., 14 figs.

  15. Pressure waves in a supersaturated bubbly magma

    USGS Publications Warehouse

    Kurzon, I.; Lyakhovsky, V.; Navon, O.; Chouet, B.

    2011-01-01

    We study the interaction of acoustic pressure waves with an expanding bubbly magma. The expansion of magma is the result of bubble growth during or following magma decompression and leads to two competing processes that affect pressure waves. On the one hand, growth in vesicularity leads to increased damping and decreased wave amplitudes, and on the other hand, a decrease in the effective bulk modulus of the bubbly mixture reduces wave velocity, which in turn, reduces damping and may lead to wave amplification. The additional acoustic energy originates from the chemical energy released during bubble growth. We examine this phenomenon analytically to identify conditions under which amplification of pressure waves is possible. These conditions are further examined numerically to shed light on the frequency and phase dependencies in relation to the interaction of waves and growing bubbles. Amplification is possible at low frequencies and when the growth rate of bubbles reaches an optimum value for which the wave velocity decreases sufficiently to overcome the increased damping of the vesicular material. We examine two amplification phase-dependent effects: (1) a tensile-phase effect in which the inserted wave adds to the process of bubble growth, utilizing the energy associated with the gas overpressure in the bubble and therefore converting a large proportion of this energy into additional acoustic energy, and (2) a compressive-phase effect in which the pressure wave works against the growing bubbles and a large amount of its acoustic energy is dissipated during the first cycle, but later enough energy is gained to amplify the second cycle. These two effects provide additional new possible mechanisms for the amplification phase seen in Long-Period (LP) and Very-Long-Period (VLP) seismic signals originating in magma-filled cracks.

  16. Generalized Langmuir Waves in Magnetized Kinetic Plasmas

    NASA Technical Reports Server (NTRS)

    Willes, A. J.; Cairns, Iver H.

    2000-01-01

    The properties of unmagnetized Langmuir waves and cold plasma magnetoionic waves (x, o, z and whistler) are well known. However, the connections between these modes in a magnetized kinetic plasma have not been explored in detail. Here, wave properties are investigated by numerically solving the dispersion equation derived from the Vlasov equations both with and without a beam instability present. For omega(sub p)>Omega(sub e), it is shown that the generalized Langmuir mode at oblique propagation angles has magnetic z-mode characteristics at low wave numbers and thermal Langmuir mode characteristics at high wave numbers. For omega(sub p)wave numbers. The transition from the Langmuir/z mode to the Langmuir/whistler mode near omega(sub p) = Omega(sub e) is rapid. In addition, the effects on wave dispersion and polarization after adding a beam are investigated. Applications of this theory to magnetized Langmuir waves in Earth's foreshock and the solar wind, to waves observed near the plasma frequency in the auroral regions, and to solar type III bursts are discussed.

  17. PDII- Additional discussion of the dynamic aperture

    SciTech Connect

    Norman M. Gelfand

    2002-07-23

    This note is in the nature of an addition to the dynamic aperture calculations found in the report on the Proton Driver, FERMILAB-TM-2169. A extensive discussion of the Proton Driver lattice, as well as the nomenclature used to describe it can be found in TM-2169. Basically the proposed lattice is a racetrack design with the two arcs joined by two long straight sections. The straight sections are dispersion free. Tracking studies were undertaken with the objective of computing the dynamic aperture for the lattice and some of the results have been incorporated into TM-2169. This note is a more extensive report of those calculations.

  18. Rust inhibiting additive compositions for oils

    SciTech Connect

    Haugen, H.

    1980-09-23

    Compositions which include mixtures of a calcium hydroxide overbased oil-soluble calcium sulfonate, hexylene glycol and a surfactant consisting of an ethoxylated aliphatic amine, particularly, diethoxylated cocoamine or diethoxylated soyamine, are useful as rust inhibiting additives for oils and the like. By incorporating these compositions in petroleum based oils such as petroleum based oils of lubricating oil quality which come into contact with metal surfaces under conditions such that the metal surfaces tend to rust or otherwise be subject to deterioration it is possible to inhibit rust formation on such metal surfaces.

  19. Models and Observations of Shock Wave Propagation in Volcanic Settings

    NASA Astrophysics Data System (ADS)

    Anderson, J.; Johnson, J. B.; Ruiz, M. C.; Steele, A.

    2013-12-01

    High-amplitude air waves (shock waves) propagate nonlinearly; although this strongly affects recorded signals, it is not commonly modeled in studies of volcanic explosions. Failure to account for the shock wave component of air waves can lead to underestimation of source power and inaccurate source times. Additionally, propagation effects can significantly alter waveforms from the original source signals. In order to permit more accurate studies of shock wave sources, we examine modeling techniques and observations of shock waves. Shock wave signals begin with strong, abrupt compressions that, compared to typical sound waves, propagate and decay more quickly. Because of the high-amplitude discontinuities, numerical methods that are commonly used to study linear sound waves become unstable and inaccurate when applied to shock waves. We discuss the use of other techniques that are capable of modeling shock wave propagation. Equations relating wave speed to the difference of various physical quantities across the shock (such as pressure, density, and particle velocity) are useful for modeling these waves. Addressing the shock explicitly as such, in conjunction with use of traditional numerical methods for the remainder of the signal, permits modeling of full shock waveforms. Additionally, we present examples of recorded volcanic signals that propagate nonlinearly and demonstrate propagation effects on amplitude, waveform, and spectrum.

  20. 3D-additive manufactured optical mount

    NASA Astrophysics Data System (ADS)

    Mammini, Paul V.; Ciscel, David; Wooten, John

    2015-09-01

    The Area Defense Anti-Munitions (ADAM) is a low cost and effective high power laser weapon system. It's designed to address and negate important threats such as short-range rockets, UAVs, and small boats. Many critical optical components operate in the system. The optics and mounts must accommodate thermal and mechanical stresses, plus maintain an exceptional wave front during operation. Lockheed Martin Space Systems Company (LMSSC) developed, designed, and currently operates ADAM. This paper covers the design and development of a key monolithic, flexured, titanium mirror mount that was manufactured by CalRAM using additive processes.

  1. Herbicidal effects of soil-incorporated wheat.

    PubMed

    Mathiassen, Solvejg K; Kudsk, Per; Mogensen, Betty B

    2006-02-22

    The hydroxamic acid 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) and the benzoxazolinones benzoxazolin-2-one (BOA) and 6-methoxybenzoxazolin-2-one (MBOA) have been identified as important allelochemicals in wheat. This study examines the possibility of exploiting the allelopathic properties of wheat as a weed control strategy by cultivating wheat as a precrop and incorporating plant residues into the soil before the next crop is sown. Different wheat varieties were cultivated in field plots during two seasons in both conventional and organic farming systems. Plants were sampled at various growth stages, and their contents of DIMBOA, MBOA, and BOA were determined by chemical analyses. The wheat samples were incorporated into soil, and the effect on germination and growth of 12 different weed species was examined in pot experiments under controlled conditions. In some cases significant effects were obtained, but the results were inconsistent and the effects were not correlated to the content of DIMBOA, MBOA, and BOA in the incorporated wheat plants. ED50 doses of the pure compounds were estimated in dose-response experiments in Petri dishes, and these turned out to be much higher than the predicted maximum concentrations of DIMBOA, MBOA, and BOA in the soil water following incorporation. The study shows that a prerequisite for exploiting the incorporation of wheat residues as a weed control strategy is the development of wheat varieties with an increased content of allelochemicals.

  2. Millimeter-wave studies

    NASA Technical Reports Server (NTRS)

    Allen, Kenneth C.

    1988-01-01

    Progress on millimeter-wave propagation experiments in Hawaii is reported. A short path for measuring attenuation in rain at 9.6, 28.8, 57.6, and 96.1 GHz is in operation. A slant path from Hilo to the top of Mauna Kea is scheduled. On this path, scattering from rain and clouds that may cause interference for satellites closely spaced in geosynchronous orbit will be measured at the same frequencies at 28.8 and 96.1 GHz. In addition the full transmission matrix will be measured at the same frequencies on the slant path. The technique and equipment used to measure the transmission matrix are described.

  3. Internal waves interacting with particles in suspension

    NASA Astrophysics Data System (ADS)

    Micard, Diane

    2016-04-01

    Internal waves are produced as a consequence of the dynamic balance between buoy- ancy and gravity forces when a particle of fluid is vertically displaced in a stable stratified environment. Geophysical systems such as ocean and atmosphere are naturally stratified and therefore suitable for internal waves to propagate. Furthermore, these two environ- ments stock a vast amount of particles in suspension, which present a large spectrum of physical properties (size, density, shape), and can be organic, mineral or pollutant agents. Therefore, it is reasonable to expect that internal waves will have an active effect over the dynamics of these particles. In order to study the interaction of internal waves and suspended particles, an ide- alized experimental setup has been implemented. A linear stratification is produced in a 80×40×17 cm3 tank, in which two dimensional plane waves are created thanks to the inno- vative wave generator GOAL. In addition, a particle injector has been developed to produce a vertical column of particles within the fluid, displaying the same two-dimensional sym- metry as the waves. The particle injector allows to control the volumic fraction of particles and the size of the column. The presence of internal waves passing through the column of particles allowed to observe two main effects: The column oscillates around an equilibrium position (which is observed in both, the contours an the interior of the column), and the column is displaced as a whole. The column is displaced depending on the characteristics of the column, the gradient of the density, and the intensity and frequency of the wave. When displaced, the particles within the column are sucked towards the source of waves. The direction of the displacement of the column is explained by computing the effect of the Lagrangian drift generated by the wave over the time the particles stay in the wave beam before settling.

  4. Reasons for the formation of incoherent additional microwaves in fresh ice under plastic deformation

    NASA Astrophysics Data System (ADS)

    Bordonskiy, G. S.

    2016-08-01

    It is supposed that incoherent additional waves that appear in fresh ice in the microwave range are associated with the spontaneous decomposition of an unstable phase. This decomposition produces periodic phases. The unstable phase may result from the plastic deformation of the ice, from vapor condensation on a cold substrate, or from other effects causing spinodals. Experimental data obtained for millimeter and centimeter waves have been presented that support the above supposition regarding the formation of the incoherent additional waves.

  5. Wave Propagation in Bimodular Geomaterials

    NASA Astrophysics Data System (ADS)

    Kuznetsova, Maria; Pasternak, Elena; Dyskin, Arcady; Pelinovsky, Efim

    2016-04-01

    Observations and laboratory experiments show that fragmented or layered geomaterials have the mechanical response dependent on the sign of the load. The most adequate model accounting for this effect is the theory of bimodular (bilinear) elasticity - a hyperelastic model with different elastic moduli for tension and compression. For most of geo- and structural materials (cohesionless soils, rocks, concrete, etc.) the difference between elastic moduli is such that their modulus in compression is considerably higher than that in tension. This feature has a profound effect on oscillations [1]; however, its effect on wave propagation has not been comprehensively investigated. It is believed that incorporation of bilinear elastic constitutive equations within theory of wave dynamics will bring a deeper insight to the study of mechanical behaviour of many geomaterials. The aim of this paper is to construct a mathematical model and develop analytical methods and numerical algorithms for analysing wave propagation in bimodular materials. Geophysical and exploration applications and applications in structural engineering are envisaged. The FEM modelling of wave propagation in a 1D semi-infinite bimodular material has been performed with the use of Marlow potential [2]. In the case of the initial load expressed by a harmonic pulse loading strong dependence on the pulse sign is observed: when tension is applied before compression, the phenomenon of disappearance of negative (compressive) strains takes place. References 1. Dyskin, A., Pasternak, E., & Pelinovsky, E. (2012). Periodic motions and resonances of impact oscillators. Journal of Sound and Vibration, 331(12), 2856-2873. 2. Marlow, R. S. (2008). A Second-Invariant Extension of the Marlow Model: Representing Tension and Compression Data Exactly. In ABAQUS Users' Conference.

  6. Converted-waves Imaging Condition for Elastic Reverse-Time Migration with Decomposed Wavefields

    NASA Astrophysics Data System (ADS)

    Kim, B.; Choi, H.; Seol, S. J.; Byun, J.

    2015-12-01

    To successfully deal with responses from the elastic earth, imaging techniques need to incorporate the elastic wave equation. Elastic Reverse-Time Migration (ERTM) with separating-while-imaging approach is capable of yielding physically meaningful PP, PS, SP, and SS images from multicomponent data. Even in PP images, ERTM has brought enhancements comparing to those from acoustic RTM because ERTM can handle converted waves. Converted-wave images, core results of ERTM, however, have two major problems related to characteristics of S-waves. First, polarity reversals according to propagation directions of S-waves cause destructive effect to final PS and SP images while each migrated result is stacked over the shots. In addition, non-existent spurious events which are produced by crosscorrelating downgoing S-waves in source wavefields and reflections associated with downgoing P-waves in receiver wavefields lead masking effects over true reflection events in SP and SS images. In this study, we adopt a wavefield decomposition method to solve the polarity problems and derive a new converted-wave imaging condition for SP and SS images to alleviate the generation of spurious events. The acceleration vector wavefield decomposition method used in our ERTM has advantages over the conventional wavefield separation method based on the Helmholtz decomposition because the wavefield decomposition can automatically compensate polarity changes in PS and SP images when the zero-lag crosscorrelation for vector wavefields is applied. To suppress spurious events in SP and SS images, our imaging condition is designed to make images only where S- and converted P-waves from source wavefields are coexisted with decomposed wavefields from receiver wavefields at reflection boundaries. To verify our new imaging condition, we tested our algorithm with OBC (Ocean Bottom Cable) data from elastic Marmousi-II model and compared the migrated images with those from ERTM with the zero

  7. High field side launch of RF waves: A new approach to reactor actuators

    NASA Astrophysics Data System (ADS)

    Wallace, G. M.; Baek, S. G.; Bonoli, P. T.; Faust, I. C.; LaBombard, B. L.; Lin, Y.; Mumgaard, R. T.; Parker, R. R.; Shiraiwa, S.; Vieira, R.; Whyte, D. G.; Wukitch, S. J.

    2015-12-01

    Launching radio frequency (RF) waves from the high field side (HFS) of a tokamak offers significant advantages over low field side (LFS) launch with respect to both wave physics and plasma material interactions (PMI). For lower hybrid (LH) waves, the higher magnetic field opens the window between wave accessibility (n∥≡c k∥/ω >√{1 -ωpi 2/ω2+ωpe 2/ωce 2 }+ωp e/|ωc e| ) and the condition for strong electron Landau damping (n∥˜√{30 /Te } with Te in keV), allowing LH waves from the HFS to penetrate into the core of a burning plasma, while waves launched from the LFS are restricted to the periphery of the plasma. The lower n∥ of waves absorbed at higher Te yields a higher current drive efficiency as well. In the ion cyclotron range of frequencies (ICRF), HFS launch allows for direct access to the mode conversion layer where mode converted waves absorb strongly on thermal electrons and ions, thus avoiding the generation of energetic minority ion tails. The absence of turbulent heat and particle fluxes on the HFS, particularly in double null configuration, makes it the ideal location to minimize PMI damage to the antenna structure. The quiescent SOL also eliminates the need to couple LH waves across a long distance to the separatrix, as the antenna can be located close to plasma without risking damage to the structure. Improved impurity screening on the HFS will help eliminate the long-standing issues of high Z impurity accumulation with ICRF. Looking toward a fusion reactor, the HFS is the only possible location for a plasma-facing RF antenna that will survive long-term. By integrating the antenna into the blanket module it is possible to improve the tritium breeding ratio compared with an antenna occupying an equatorial port plug. Blanket modules will require remote handling of numerous cooling pipes and electrical connections, and the addition of transmission lines will not substantially increase the level of complexity. The obvious engineering

  8. Interfacial wave theory for dendritic structure of a growing needle crystal. I - Local instability mechanism. II - Wave-emission mechanism at the turning point

    NASA Technical Reports Server (NTRS)

    Xu, Jian-Jun

    1989-01-01

    The complicated dendritic structure of a growing needle crystal is studied on the basis of global interfacial wave theory. The local dispersion relation for normal modes is derived in a paraboloidal coordinate system using the multiple-variable-expansion method. It is shown that the global solution in a dendrite growth process incorporates the morphological instability factor and the traveling wave factor.

  9. Dust-Acoustic Waves: Visible Sound Waves

    SciTech Connect

    Merlino, Robert L.

    2009-11-10

    A historical overview of some of the early theoretical and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some of the theoretical refinements that have been made, including the effects of collisions, plasma absorption, dust charge fluctuations, particle drifts and strong coupling effects are discussed. Some recent experimental findings and outstanding problems are also presented.

  10. Nonlinear scattering of acoustic waves by vibrating obstacles

    NASA Astrophysics Data System (ADS)

    Piquette, J. C.

    1983-06-01

    The problem of the generation of sum- and difference-frequency waves produced via the scattering of an acoustic wave by an obstacle whose surface vibrates harmonically was studied both theoretically and experimentally. The theoretical approach involved solving the nonlinear wave equation, subject to appropriate boundary conditions, by the use of a perturbation expansion of the fields and a Green's function method. In addition to ordinary rigid-body scattering, Censor predicted nongrowing waves at frequencies equal to the sum and to the difference of the frequencies of the primary waves. The solution to the nonlinear wave equation also yields scattered waves at the sum and difference frequencies. However, the nonlinearity of the medium causes these waves to grow with increasing distance from the scatter's surface and, after a very small distance, dominate those predicted by Censor. The simple-source formulation of the second-order nonlinear wave equation for a lossless fluid medium has been derived for arbitrary primary wave fields. This equation was used to solve the problem of nonlinear scattering of acoustic waves by a vibrating obstacle for three geometries: (1) a plane-wave scattering by a vibrating plane, (2) cylindrical-wave scattering by a vibrating cylinder, and (3) plane-wave scattering by a vibrating cylinder. Successful experimental validation of the theory was inhibited by previously unexpected levels of nonlinearity in the hydrophones used. Such high levels of hydrophone nonlinearity appeared in hydrophones that, by their geometry of construction, were expected to be fairly linear.

  11. Therapy for incorporated radionuclides: scope and need

    SciTech Connect

    Smith, V.H.

    1981-03-01

    In the United States the recent termination of funding for research on therapy for incorporated radionuclides has virtually halted progress on improved or new agents and procedures for removing radioactivity from the body. Research was eliminated, but is still needed on new removal agents, improved delivery system, in vitro test systems, and the toxicology of treatments. For many radionuclides, no adequate therapy exists. The relationship between radionuclide removal and reduction in cancer risk is still unanswered. Without proper research support, needed improvements in the treatment for incorporated radionuclides in the US are uncertain.

  12. 48 CFR 52.102 - Incorporating provisions and clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... incorporated by reference to the maximum practical extent, rather than being incorporated in full text, even if... provide the full text of any provision or clause incorporated by reference. (c) Agency approved provisions... subpart 52.3 to be incorporated by reference, need not be incorporated in full text, provided...

  13. 48 CFR 52.102 - Incorporating provisions and clauses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... incorporated by reference to the maximum practical extent, rather than being incorporated in full text, even if... provide the full text of any provision or clause incorporated by reference. (c) Agency approved provisions... subpart 52.3 to be incorporated by reference, need not be incorporated in full text, provided...

  14. Role of Hydraulic Geometry in Flood Wave Propagation

    NASA Astrophysics Data System (ADS)

    Orlandini, S.

    2010-12-01

    The role of hydraulic geometry in flood wave propagation is investigated by using a diffusion wave model with inertial effects. Power function relationships W = a’Qb’ and kS = r’Qy’ are used to reproduce the at-a-station variations of water-surface width W and Gauckler-Strickler conductance coefficient kS (the inverse of Manning resistance coefficient) with flow discharge Q. Downstream variations of coefficients a’ and r’ are not considered in this study. The considered hydraulic geometry relationships are incorporated into a diffusion wave model in which the term (1 - Ve2), Ve being the Vedernikov number, multiplies the Hayami’s diffusivity Q/(2WS0), S0 being the channel bed slope. This mathematical model is solved numerically by using a matched artificial diffusivity method. Numerical experiments are carried out by evaluating peak attenuation and mean peak celerity of flood waves propagating along channel reaches characterized by coefficients a’ and r’ equal to the average values observed in natural rivers, by all the combinations of exponents b’ and y’ laying in the range 0-0.5, and by values of S0 laying in the range 0.000125-0.032. It is found that: (1) peak attenuation and mean peak celerity display the minimum values for b’ = 0.5 and y’ = 0, (2) for high values of y’, Ve displays values greater than 1 indicating physical instability of flood waves, and (3) around the condition b’ = 0 and y’ = 0, for high values of Q/W and low values of S0, the Peclet number Pe (evaluated over the channel reach length) displays values less than 2 indicating unrealistic hydraulic diffusion (more storage effects than those produced by a reservoir). The region of the plane b’y’ representing relevant flood waves lays therefore between the instability region Ve > 1, where unstable flood waves are physically possible but rarely observed in natural channels and not reproducible with the considered model, and the region of unrealistic diffusion Pe

  15. Raman spectroscopy of hypersonic shock waves

    PubMed

    Ramos; Mate; Tejeda; Fernandez; Montero

    2000-10-01

    Raman spectroscopy is shown to be an efficient diagnostic methodology for the study of hypersonic shock waves. As a test, absolute density and rotational population profiles have been measured across five representative normal shock waves of N2 generated in a free jet, spanning the Mach number range 7.7waves shows a largely bimodal rotational distribution function with additional contribution of scattered molecules, in close analogy with the velocity distribution function known from helium shock waves [G. Pham-Van-Diep et al., Science 245, 624 (1989)]. Quantitative data on invariance trends of density profiles and properties of the wake beyond the shock waves are reported.

  16. Pulse Wave Propagation in the Arterial Tree

    NASA Astrophysics Data System (ADS)

    van de Vosse, Frans N.; Stergiopulos, Nikos

    2011-01-01

    The beating heart creates blood pressure and flow pulsations that propagate as waves through the arterial tree that are reflected at transitions in arterial geometry and elasticity. Waves carry information about the matter in which they propagate. Therefore, modeling of arterial wave propagation extends our knowledge about the functioning of the cardiovascular system and provides a means to diagnose disorders and predict the outcome of medical interventions. In this review we focus on the physical and mathematical modeling of pulse wave propagation, based on general fluid dynamical principles. In addition we present potential applications in cardiovascular research and clinical practice. Models of short- and long-term adaptation of the arterial system and methods that deal with uncertainties in personalized model parameters and boundary conditions are briefly discussed, as they are believed to be major topics for further study and will boost the significance of arterial pulse wave modeling even more.

  17. Inertio Gravity Waves in the Upper Mesosphere

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Mengel, J. G.; Talaat, E. L.; Porter, H. S.; Chan, K. L.

    2003-01-01

    In the polar region of the upper mesosphere, horizontal wind oscillations have been observed with periods around 10 hours (Hernandez et al., 1992). Such waves are generated in our Numerical Spectral Model (NSM) and appear to be inertio gravity waves (IGW). Like the planetary waves (PW) in the model, the IGWs are generated by instabilities that arise in the mean zonal circulation. In addition to stationary waves for m = 0, eastward and westward propagating waves for m = 1 to 4 appear above 70 km that grow in magnitude up to about 110 km, having periods between 9 and 11 hours. The m = 1 westward propagating IGWs have the largest amplitudes, which can reach at the poles 30 m/s. Like PWs, the IGWs are intermittent but reveal systematic seasonal variations, with the largest amplitudes occurring generally in winter and spring. The IGWs propagate upward with a vertical wavelength of about 20 km.

  18. Rogue waves of the Kundu-Eckhaus equation in a chaotic wave field.

    PubMed

    Bayindir, Cihan

    2016-03-01

    In this paper we study the properties of the chaotic wave fields generated in the frame of the Kundu-Eckhaus equation (KEE). Modulation instability results in a chaotic wave field which exhibits small-scale filaments with a free propagation constant, k. The average velocity of the filaments is approximately given by the average group velocity calculated from the dispersion relation for the plane-wave solution; however, direction of propagation is controlled by the β parameter, the constant in front of the Raman-effect term. We have also calculated the probabilities of the rogue wave occurrence for various values of propagation constant k and showed that the probability of rogue wave occurrence depends on k. Additionally, we have showed that the probability of rogue wave occurrence significantly depends on the quintic and the Raman-effect nonlinear terms of the KEE. Statistical comparisons between the KEE and the cubic nonlinear Schrödinger equation have also been presented.

  19. Analytic methods for design of wave cycles for wave rotor core engines

    NASA Technical Reports Server (NTRS)

    Resler, Edwin L., Jr.; Mocsari, Jeffrey C.; Nalim, M. R.

    1993-01-01

    A procedure to design a preliminary wave rotor cycle for any application is presented. To complete a cycle with heat addition there are two separate but related design steps that must be followed. The 'wave' boundary conditions determine the allowable amount of heat added in any case and the ensuing wave pattern requires certain pressure discharge conditions to allow the process to be made cyclic. This procedure, when applied, gives a first estimate of the cycle performance and the necessary information for the next step in the design process, namely the application of a characteristic based or other appropriate detailed one dimensional wave calculation that locates the proper porting around the periphery of the wave rotor. Four examples of the design procedure are given to demonstrate its utility and generality. These examples also illustrate the large gains in performance that could be realized with the use of wave rotor enhanced propulsion cycles.

  20. The Virtual Wave Observatory (VWO): A Portal to Heliophysics Wave Data

    NASA Technical Reports Server (NTRS)

    Fung, Shing F.

    2010-01-01

    The Virtual Wave Observatory (VWO) is one of the discipline-oriented virtual observatories that help form the nascent NASA Heliophysics Data environment to support heliophysics research. It focuses on supporting the searching and accessing of distributed heliophysics wave data and information that are available online. Since the occurrence of a natural wave phenomenon often depends on the underlying geophysical -- i.e., context -- conditions under which the waves are generated and propagate, and the observed wave characteristics can also depend on the location of observation, VWO will implement wave-data search-by-context conditions and location, in addition to searching by time and observing platforms (both space-based and ground-based). This paper describes the VWO goals, the basic design objectives, and the key VWO functionality to be expected. Members of the heliophysics community are invited to participate in VWO development in order to ensure its usefulness and success.

  1. Rogue waves of the Kundu-Eckhaus equation in a chaotic wave field

    NASA Astrophysics Data System (ADS)

    Bayindir, Cihan

    2016-03-01

    In this paper we study the properties of the chaotic wave fields generated in the frame of the Kundu-Eckhaus equation (KEE). Modulation instability results in a chaotic wave field which exhibits small-scale filaments with a free propagation constant, k . The average velocity of the filaments is approximately given by the average group velocity calculated from the dispersion relation for the plane-wave solution; however, direction of propagation is controlled by the β parameter, the constant in front of the Raman-effect term. We have also calculated the probabilities of the rogue wave occurrence for various values of propagation constant k and showed that the probability of rogue wave occurrence depends on k . Additionally, we have showed that the probability of rogue wave occurrence significantly depends on the quintic and the Raman-effect nonlinear terms of the KEE. Statistical comparisons between the KEE and the cubic nonlinear Schrödinger equation have also been presented.

  2. Detonation Wave Profile

    SciTech Connect

    Menikoff, Ralph

    2015-12-14

    The Zel’dovich-von Neumann-Doering (ZND) profile of a detonation wave is derived. Two basic assumptions are required: i. An equation of state (EOS) for a partly burned explosive; P(V, e, λ). ii. A burn rate for the reaction progress variable; d/dt λ = R(V, e, λ). For a steady planar detonation wave the reactive flow PDEs can be reduced to ODEs. The detonation wave profile can be determined from an ODE plus algebraic equations for points on the partly burned detonation loci with a specified wave speed. Furthermore, for the CJ detonation speed the end of the reaction zone is sonic. A solution to the reactive flow equations can be constructed with a rarefaction wave following the detonation wave profile. This corresponds to an underdriven detonation wave, and the rarefaction is know as a Taylor wave.

  3. Traveling Wave Demonstration.

    ERIC Educational Resources Information Center

    Kluger-Bell, Barry

    1995-01-01

    Describes a traveling-wave demonstration that uses inexpensive materials (crepe-paper streamers) and is simple to assemble and perform. Explains how the properties of light waves are illustrated using the demonstration apparatus. (LZ)

  4. A new car-following model with the consideration of incorporating timid and aggressive driving behaviors

    NASA Astrophysics Data System (ADS)

    Peng, Guanghan; He, Hongdi; Lu, Wei-Zhen

    2016-01-01

    In this paper, a new car-following model is proposed with the consideration of the incorporating timid and aggressive behaviors on single lane. The linear stability condition with the incorporating timid and aggressive behaviors term is obtained. Numerical simulation indicates that the new car-following model can estimate proper delay time of car motion and kinematic wave speed at jam density by considering the incorporating the timid and aggressive behaviors. The results also show that the aggressive behavior can improve traffic flow while the timid behavior deteriorates traffic stability, which means that the aggressive behavior is better than timid behavior since the aggressive driver makes rapid response to the variation of the velocity of the leading car. Snapshot of the velocities also shows that the new model can approach approximation to a wide moving jam.

  5. Kinetics of Incorporation of Structural Proteins into Sindbis Virions

    PubMed Central

    Scheele, Christina M.; Pfefferkorn, E. R.

    1969-01-01

    The morphogenesis of Sindbis virus was studied by determining the kinetics with which newly synthesized nucleocapsid and envelope proteins appeared in virions released into the extracellular medium. Assembly of the nucleocapsid was more rapid than modification of the cellular membrane by the addition of the viral envelope protein. However, both viral structural proteins were efficiently incorporated into virions; a 0.5-hr pulse-labeling period resulted in the release of maximally labeled virus during the next hour. When protein synthesis was inhibited, release of virus soon declined even though large amounts of both viral structural proteins were present within the cell and ribonucleic acid replication was unaffected. PMID:5771964

  6. Incorporation Of Nanocrystalline Silver on Carbon Nanotubes by Electrodeposition Technique

    NASA Astrophysics Data System (ADS)

    Hussain, S.; Pal, A. K.

    2008-10-01

    Nanocrystalline silver incorporated carbon nanotubes were grown on Si (001) substrate from an electrolytic bath containing acetonitrile (1% v/v) and water with appropriate amount of silver acetate at an applied d.c. potential ˜20V. The films were characterized by measuring their microstructural properties, FTIR and Raman studies. HRTEM image indicated that the diameter of the nanotubes as ˜5 nm and the d spacing as ˜0.34 nm for (002) plane of CNT. With the addition of nanocrystalline silver, the intensity of G-band decreases while the D-band located ˜1352 cm-1 becomes sharper.

  7. Constructing the frequency and wave normal distribution of whistler-mode wave power

    NASA Astrophysics Data System (ADS)

    Watt, C. E. J.; Degeling, A. W.; Rankin, R.

    2013-05-01

    We introduce a new methodology that allows the construction of wave frequency distributions due to growing incoherent whistler-mode waves in the magnetosphere. The technique combines the equations of geometric optics (i.e., raytracing) with the equation of transfer of radiation in an anisotropic lossy medium to obtain spectral energy density as a function of frequency and wavenormal angle. We describe the method in detail and then demonstrate how it could be used in an idealized magnetosphere during quiet geomagnetic conditions. For a specific set of plasma conditions, we predict that the wave power peaks off the equator at ˜15° magnetic latitude. The new calculations predict that wave power as a function of frequency can be adequately described using a Gaussian function, but as a function of wavenormal angle, it more closely resembles a skew normal distribution. The technique described in this paper is the first known estimate of the parallel and oblique incoherent wave spectrum as a result of growing whistler-mode waves and provides a means to incorporate self-consistent wave-particle interactions in a kinetic model of the magnetosphere over a large volume.

  8. Direct incorporation of GDP into microtubules without GTP hydrolysis

    SciTech Connect

    Lin, C.M.; Hamel, E.

    1987-05-01

    Tubulin bearing (8-/sup 14/C)GDP in the exchangeable nucleotide binding site was prepared, and its polymerization was examined with microtubule-associated proteins containing minimal nucleoside diphosphate kinase and nonspecific phosphatase contamination. Although microtubule assembly required GTP, significant incorporation of tubulin-bound GDP into microtubules without exchange of the radiolabeled GDP for GTP was observed under reaction conditions which favored an increased proportion of tubulin x GDP relative to tubulin x GTP. These were low GTP concentrations, low Mg/sup 2 +/ concentrations, high tubulin concentrations, and exogenous GDP in the reaction mixture. The minimum tubulin x GTP:tubulin x GDP ratio required for microtubule assembly was determined to establish the relative importance of the two tubulin species in the initiation of assembly and was found to be about 2:1. In addition, the relative efficiency with which tubulin x GTP and tubulin x GDP were incorporated into microtubules was determined. They found that tubulin x GDP was incorporated into polymer about half as efficiently as tubulin x GTP.

  9. Bioactivity of 2′-deoxyinosine-incorporated aptamer AS1411

    PubMed Central

    Fan, Xinmeng; Sun, Lidan; Wu, Yun; Zhang, Lihe; Yang, Zhenjun

    2016-01-01

    Aptamers can be chemically modified to enhance nuclease resistance and increase target affinity. In this study, we performed chemical modification of 2′-deoxyinosine in AS1411, an anti-proliferative G-rich oligodeoxynucleotide aptamer, which binds selectively to the nucleolin protein. Its function was augmented when 2′-deoxyinosine was incorporated at positions 12, 13, 15, and 24 of AS1411, respectively. In addition, double incorporation of 2′-deoxyinosine at positions 12 and 24 (FAN-1224dI), 13 and 24 (FAN-1324dI), and 15 and 24 (FAN-1524dI) promoted G-quartet formation, as well as inhibition of DNA replication and tumor cell growth, and induced S-phase cell cycle arrest. In further animal experiments, FAN-1224dI, FAN-1324dI and FAN-1524dI resulted in enhanced treatment effects than AS1411 alone. These results suggested that the position and number of modification substituents in AS1411 are critical parameters to improve the diagnostic and therapeutic function of the aptamer. Structural investigations of the FAN-1524dI/nucleolin complex structure, using molecular dynamics simulation, revealed the critical interactions involving nucleolin and 2′-dI incorporated AS1411 compared with AS1411 alone. These findings augment understanding of the role of 2′-deoxyinosine moieties in interactive binding processes. PMID:27194215

  10. Bioactivity of 2'-deoxyinosine-incorporated aptamer AS1411.

    PubMed

    Fan, Xinmeng; Sun, Lidan; Wu, Yun; Zhang, Lihe; Yang, Zhenjun

    2016-05-19

    Aptamers can be chemically modified to enhance nuclease resistance and increase target affinity. In this study, we performed chemical modification of 2'-deoxyinosine in AS1411, an anti-proliferative G-rich oligodeoxynucleotide aptamer, which binds selectively to the nucleolin protein. Its function was augmented when 2'-deoxyinosine was incorporated at positions 12, 13, 15, and 24 of AS1411, respectively. In addition, double incorporation of 2'-deoxyinosine at positions 12 and 24 (FAN-1224dI), 13 and 24 (FAN-1324dI), and 15 and 24 (FAN-1524dI) promoted G-quartet formation, as well as inhibition of DNA replication and tumor cell growth, and induced S-phase cell cycle arrest. In further animal experiments, FAN-1224dI, FAN-1324dI and FAN-1524dI resulted in enhanced treatment effects than AS1411 alone. These results suggested that the position and number of modification substituents in AS1411 are critical parameters to improve the diagnostic and therapeutic function of the aptamer. Structural investigations of the FAN-1524dI/nucleolin complex structure, using molecular dynamics simulation, revealed the critical interactions involving nucleolin and 2'-dI incorporated AS1411 compared with AS1411 alone. These findings augment understanding of the role of 2'-deoxyinosine moieties in interactive binding processes.

  11. Many-body wave functions

    SciTech Connect

    Chasman, R.R.

    1995-08-01

    In the past few years, we developed many-body variational wave functions that allow one to treat pairing and particle-hole two-body interactions on an equal footing. The complexity of these wave functions depends on the number of levels included in the valence space, but does not depend on the number of nucleons in the system. By using residual interaction strengths (e.g. the quadrupole interaction strength or pairing interaction strength) as generator coordinates, one gets many different wave functions, each having a different expectation value for the relevant interaction mode. These wave functions are particularly useful when one is dealing with a situation in which the mean-field approximation is inadequate. Because the same basis states are used in the construction of the many-body wave functions, it is possible to calculate overlaps and interaction matrix elements for the many-body wave functions (which are not in general orthogonal) easily. The valence space can contain a large number of single-particle basis states, when there are constants of motion that can be used to break the levels up into groups. We added a cranking term to the many-body Hamiltonian and modified the projection procedure to get states of good signature before variation. In our present implementation, each group is limited to eight pairs of single-particle levels. We are working on ways of increasing the number of levels that can be included in each group. We are also working on including particle-particle residual interaction modes, in addition to pairing, in our Hamiltonian.

  12. Wave climatology of Lake Erie based on an unstructured-grid wave model

    NASA Astrophysics Data System (ADS)

    Niu, Qianru; Xia, Meng

    2016-08-01

    Hindcast of wave dynamics in Lake Erie during 2002 to 2012 was conducted using a state-of-art finite-volume coastal ocean surface wave model (FVCOM-SWAVE). After model calibration, the surface gravity wave dynamics were examined from the aspects of wave climate and seasonality, inter-basin wave interactions, as well as its potential susceptibility to regional climate change. Compared to the Central and Eastern Basins, the Western Basin has relatively gentle wave climate. The Western Basin and the nearshore areas are most susceptible to the wave-induced bottom orbital oscillations on the seasonal mean scale, and the offshore Central Basin is sensitive to them as well during episodic events. Profound seasonality was found in both mean and extreme wave dynamics during ice-free cycles. Mean significant wave height (SWH) is highest during fall with more occurrences of extreme events (SWH > 3.1 m) and is lowest during summer, which is controlled by wind speed and direction collectively. Besides, swells generated in the Central and Eastern Basins could interact with each other under various wind directions, whereas wave generated in the Central Basin could hardly propagate into the Western Basin. In addition, the regression analysis of surrounding meteorological stations indicates increasing SWH in the Western Basin and decreasing SWH in the Eastern Basin.

  13. Wave climatology of Lake Erie based on an unstructured-grid wave model

    NASA Astrophysics Data System (ADS)

    Niu, Qianru; Xia, Meng

    2016-10-01

    Hindcast of wave dynamics in Lake Erie during 2002 to 2012 was conducted using a state-of-art finite-volume coastal ocean surface wave model (FVCOM-SWAVE). After model calibration, the surface gravity wave dynamics were examined from the aspects of wave climate and seasonality, inter-basin wave interactions, as well as its potential susceptibility to regional climate change. Compared to the Central and Eastern Basins, the Western Basin has relatively gentle wave climate. The Western Basin and the nearshore areas are most susceptible to the wave-induced bottom orbital oscillations on the seasonal mean scale, and the offshore Central Basin is sensitive to them as well during episodic events. Profound seasonality was found in both mean and extreme wave dynamics during ice-free cycles. Mean significant wave height (SWH) is highest during fall with more occurrences of extreme events (SWH > 3.1 m) and is lowest during summer, which is controlled by wind speed and direction collectively. Besides, swells generated in the Central and Eastern Basins could interact with each other under various wind directions, whereas wave generated in the Central Basin could hardly propagate into the Western Basin. In addition, the regression analysis of surrounding meteorological stations indicates increasing SWH in the Western Basin and decreasing SWH in the Eastern Basin.

  14. Oceanic wave measurement system

    NASA Technical Reports Server (NTRS)

    Holmes, J. F.; Miles, R. T. (Inventor)

    1980-01-01

    An oceanic wave measured system is disclosed wherein wave height is sensed by a barometer mounted on a buoy. The distance between the trough and crest of a wave is monitored by sequentially detecting positive and negative peaks of the output of the barometer and by combining (adding) each set of two successive half cycle peaks. The timing of this measurement is achieved by detecting the period of a half cycle of wave motion.

  15. Heat waves in the United States: definitions, patterns and trends.

    PubMed

    Smith, Tiffany T; Zaitchik, Benjamin F; Gohlke, Julia M

    2013-06-01

    High temperatures and heat waves are related but not synonymous concepts. Heat waves, generally understood to be acute periods of extreme warmth, are relevant to a wide range of stakeholders because of the impacts that these events have on human health and activities and on natural environments. Perhaps because of the diversity of communities engaged in heat wave monitoring and research, there is no single, standard definition of a heat wave. Experts differ in which threshold values (absolute versus relative), duration and ancillary variables to incorporate into heat wave definitions. While there is value in this diversity of perspectives, the lack of a unified index can cause confusion when discussing patterns, trends, and impacts. Here, we use data from the North American Land Data Assimilation System to examine patterns and trends in 15 previously published heat wave indices for the period 1979-2011 across the Continental United States. Over this period the Southeast region saw the highest number of heat wave days for the majority of indices considered. Positive trends (increases in number of heat wave days per year) were greatest in the Southeast and Great Plains regions, where more than 12 % of the land area experienced significant increases in the number of heat wave days per year for the majority of heat wave indices. Significant negative trends were relatively rare, but were found in portions of the Southwest, Northwest, and Great Plains.

  16. Heat waves in the United States: definitions, patterns and trends

    PubMed Central

    Zaitchik, Benjamin F.; Gohlke, Julia M.

    2012-01-01

    High temperatures and heat waves are related but not synonymous concepts. Heat waves, generally understood to be acute periods of extreme warmth, are relevant to a wide range of stakeholders because of the impacts that these events have on human health and activities and on natural environments. Perhaps because of the diversity of communities engaged in heat wave monitoring and research, there is no single, standard definition of a heat wave. Experts differ in which threshold values (absolute versus relative), duration and ancillary variables to incorporate into heat wave definitions. While there is value in this diversity of perspectives, the lack of a unified index can cause confusion when discussing patterns, trends, and impacts. Here, we use data from the North American Land Data Assimilation System to examine patterns and trends in 15 previously published heat wave indices for the period 1979–2011 across the Continental United States. Over this period the Southeast region saw the highest number of heat wave days for the majority of indices considered. Positive trends (increases in number of heat wave days per year) were greatest in the Southeast and Great Plains regions, where more than 12 % of the land area experienced significant increases in the number of heat wave days per year for the majority of heat wave indices. Significant negative trends were relatively rare, but were found in portions of the Southwest, Northwest, and Great Plains. PMID:23869115

  17. Semiconducting compounds and devices incorporating same

    SciTech Connect

    Marks, Tobin J; Facchetti, Antonio; Boudreault, Pierre-Luc; Miyauchi, Hiroyuki

    2014-06-17

    Disclosed are molecular and polymeric compounds having desirable properties as semiconducting materials. Such compounds can exhibit desirable electronic properties and possess processing advantages including solution-processability and/or good stability. Organic transistor and photovoltaic devices incorporating the present compounds as the active layer exhibit good device performance.

  18. Incorporating the Aesthetic Dimension into Pedagogy

    ERIC Educational Resources Information Center

    Webster, R. Scott; Wolfe, Melissa

    2013-01-01

    This paper reports on a case study that was undertaken to discover not only the belief and intent behind the everyday opportunities that four exemplary teachers offered their high performing students but what activities they incorporated into their everyday lessons in an attempt to make sense of how aesthetic experiences may enhance learning. The…

  19. Incorporating PACER into an Inclusive Basketball Unit

    ERIC Educational Resources Information Center

    Cervantes, Carlos M.; Cohen, Rona; Hersman, Bethany L.; Barrett, Tim

    2007-01-01

    Cooperative learning is an instructional method designed to teach students to work together in small, structured, heterogeneous teams to achieve a common goal. The Performer and Coach Earn Rewards (PACER) system is a new way to incorporate cooperative learning in the gymnasium. It consists of six components that help teachers to introduce new…

  20. Incorporating Feminism into Rehabilitation Counselor Education

    ERIC Educational Resources Information Center

    Jeon, Mookyong

    2015-01-01

    Purpose: The author describes how rehabilitation counselor educators can incorporate the feminist perspective in teaching rehabilitation counselors-in-training by exploring history, core values, and training methods of feminism. Method: Based on a literature review, the author compares philosophy and concepts of rehabilitation counseling and…

  1. 49 CFR 572.180 - Incorporated materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CFR part 51. Copies of the materials may be inspected at the Department of Transportation, Docket.... 175-6000 Pelvis Assembly; (xi) Drawing No. 175-7000-1, Leg Assembly—left; (xii) Drawing No. 175-7000-2...; (x) Drawing No. 175-6000, Pelvis Assembly, incorporated by reference in §§ 572.181 and 572.188;...

  2. Experience with an ICD incorporating biventricular pacing.

    PubMed

    Kühlkamp, V; Dörnberger, V; Rüb, N; Eigenberger, B; Kettering, K; Bosch, R; Mewis, C

    2003-04-01

    Biventricular pacing for cardiac resynchronization is a promising therapy for symptomatic improvement in selected patients with underlying severe congestive heart failure. ICD treatment has been shown to prolong life in patients with life threatening ventricular tachyarrhythmias, but it does not improve quality of life. This review discusses current experience with ICD's incorporating biventricular pacing.

  3. Incorporating Engineering Design Challenges into STEM Courses

    ERIC Educational Resources Information Center

    Householder, Daniel L., Ed.; Hailey, Christine E., Ed.

    2012-01-01

    Successful strategies for incorporating engineering design challenges into science, technology, engineering, and mathematics (STEM) courses in American high schools are presented in this paper. The developers have taken the position that engineering design experiences should be an important component of the high school education of all American…

  4. Incorporating Mobile Learning into Athletic Training Education

    ERIC Educational Resources Information Center

    Davie, Emily

    2009-01-01

    Objective: To introduce and present techniques for incorporating mobile learning into athletic training education. Background: The matriculation of digital natives into college has stimulated the identification and development of new teaching and learning strategies. Electronic learning (e-learning), including the use of learning management…

  5. Incorporating the Internet into Traditional Library Instruction.

    ERIC Educational Resources Information Center

    Fonseca, Tony; King, Monica

    2000-01-01

    Presents a template for teaching traditional library research and one for incorporating the Web. Highlights include the differences between directories and search engines; devising search strategies; creating search terms; how to choose search engines; evaluating online resources; helpful Web sites; and how to read URLs to evaluate a Web site's…

  6. Incorporating Social Media in the Classroom

    ERIC Educational Resources Information Center

    McMeans, April

    2015-01-01

    Incorporating social media into the classroom will provide a positive, upbeat learning environment that students are engaged in on a regular basis. In doing this, educators will be ensuring discussion, collaboration, critical thinking, and creativity amongst their students. Social media is a knowledgeable topic for our students, and it is an…

  7. Semiconducting compounds and devices incorporating same

    DOEpatents

    Marks, Tobin J.; Facchetti, Antonio; Boudreault, Pierre-Luc; Miyauchi, Hiroyuki

    2016-01-19

    Disclosed are molecular and polymeric compounds having desirable properties as semiconducting materials. Such compounds can exhibit desirable electronic properties and possess processing advantages including solution-processability and/or good stability. Organic transistor and photovoltaic devices incorporating the present compounds as the active layer exhibit good device performance.

  8. Design of Schools to Incorporate Fallout Protection.

    ERIC Educational Resources Information Center

    Folley, Milo D.

    Means are suggested by which a school district may incorporate low-cost fallout protection in a school construction program, through construction of an underground shelter beneath the concrete slab foundation. Ways of controlling distribution and filtering air are discussed. The author also suggests consideration of a completely underground…

  9. Combined cycle power plant incorporating coal gasification

    DOEpatents

    Liljedahl, Gregory N.; Moffat, Bruce K.

    1981-01-01

    A combined cycle power plant incorporating a coal gasifier as the energy source. The gases leaving the coal gasifier pass through a liquid couplant heat exchanger before being used to drive a gas turbine. The exhaust gases of the gas turbine are used to generate both high pressure and low pressure steam for driving a steam turbine, before being exhausted to the atmosphere.

  10. The Incorporation and Abjection of Official Knowledge

    ERIC Educational Resources Information Center

    Kearl, Benjamin Kelsey

    2012-01-01

    In this essay, the author analyzes two theoretical perspectives--incorporation and abjection--that inform official knowledge generally and high school American history textbooks specifically. While contemporary textbooks increasingly depict the experiences of historically marginalized groups such as women, African Americans, Latinos, American…

  11. Enhanced Sensitive Love Wave Surface Acoustic Wave Sensor Designed for Immunoassay Formats

    PubMed Central

    Puiu, Mihaela; Gurban, Ana-Maria; Rotariu, Lucian; Brajnicov, Simona; Viespe, Cristian; Bala, Camelia

    2015-01-01

    We report a Love wave surface acoustic wave (LW-SAW) immunosensor designed for the detection of high molecular weight targets in liquid samples, amenable also for low molecular targets in surface competition assays. We implemented a label-free interaction protocol similar to other surface plasmon resonance bioassays having the advantage of requiring reduced time analysis. The fabricated LW-SAW sensor supports the detection of the target in the nanomolar range, and can be ultimately incorporated in portable devices, suitable for point-of-care testing (POCT) applications. PMID:25951337

  12. Enhanced sensitive love wave surface acoustic wave sensor designed for immunoassay formats.

    PubMed

    Puiu, Mihaela; Gurban, Ana-Maria; Rotariu, Lucian; Brajnicov, Simona; Viespe, Cristian; Bala, Camelia

    2015-05-05

    We report a Love wave surface acoustic wave (LW-SAW) immunosensor designed for the detection of high molecular weight targets in liquid samples, amenable also for low molecular targets in surface competition assays. We implemented a label-free interaction protocol similar to other surface plasmon resonance bioassays having the advantage of requiring reduced time analysis. The fabricated LW-SAW sensor supports the detection of the target in the nanomolar range, and can be ultimately incorporated in portable devices, suitable for point-of-care testing (POCT) applications.

  13. Waves of Hanta

    NASA Astrophysics Data System (ADS)

    Abramson, Guillermo

    2003-03-01

    A spatially extended model of the hantavirus infection in deer mice is analyzed. Traveling waves solutions of the infected and susceptible populations are studied in different regimes, controlled by an environmental parameter. The wave of infection is shown to lag behind the wave of susceptible population, and the delay between the two is analyzed numerically and through a piecewise linearization.

  14. Additional calculations of triton moments

    NASA Astrophysics Data System (ADS)

    Lally, D. F.; Levinger, J. S.

    1982-02-01

    The formalism of hyperspherical harmonics is used to calculate several moments of the triton photoeffect for a Volkov potential with Serber exchange. The accuracy of Clare's calculations of moments σ0 and σ1 is improved by including more terms in the hyperspherical harmonic expansion of the potential and of the ground state wave function. The moment σ2=8.9×104 MeV3 mb is calculated using one term in the hyperspherical harmonic expansions of the potential and wave function. We invert four moments and find reasonable agreement with Gorbunov's measurements of the 3He photoeffect. NUCLEAR REACTIONS Triton photoeffect, hyperspherical harmonics, moments of photoeffect, inversion of moments.

  15. A metasurface carpet cloak for electromagnetic, acoustic and water waves.

    PubMed

    Yang, Yihao; Wang, Huaping; Yu, Faxin; Xu, Zhiwei; Chen, Hongsheng

    2016-01-29

    We propose a single low-profile skin metasurface carpet cloak to hide objects with arbitrary shape and size under three different waves, i.e., electromagnetic (EM) waves, acoustic waves and water waves. We first present a metasurface which can control the local reflection phase of these three waves. By taking advantage of this metasurface, we then design a metasurface carpet cloak which provides an additional phase to compensate the phase distortion introduced by a bump, thus restoring the reflection waves as if the incident waves impinge onto a flat mirror. The finite element simulation results demonstrate that an object can be hidden under these three kinds of waves with a single metasurface cloak.

  16. A metasurface carpet cloak for electromagnetic, acoustic and water waves

    PubMed Central

    Yang, Yihao; Wang, Huaping; Yu, Faxin; Xu, Zhiwei; Chen, Hongsheng

    2016-01-01

    We propose a single low-profile skin metasurface carpet cloak to hide objects with arbitrary shape and size under three different waves, i.e., electromagnetic (EM) waves, acoustic waves and water waves. We first present a metasurface which can control the local reflection phase of these three waves. By taking advantage of this metasurface, we then design a metasurface carpet cloak which provides an additional phase to compensate the phase distortion introduced by a bump, thus restoring the reflection waves as if the incident waves impinge onto a flat mirror. The finite element simulation results demonstrate that an object can be hidden under these three kinds of waves with a single metasurface cloak. PMID:26822429

  17. A metasurface carpet cloak for electromagnetic, acoustic and water waves

    NASA Astrophysics Data System (ADS)

    Yang, Yihao; Wang, Huaping; Yu, Faxin; Xu, Zhiwei; Chen, Hongsheng

    2016-01-01

    We propose a single low-profile skin metasurface carpet cloak to hide objects with arbitrary shape and size under three different waves, i.e., electromagnetic (EM) waves, acoustic waves and water waves. We first present a metasurface which can control the local reflection phase of these three waves. By taking advantage of this metasurface, we then design a metasurface carpet cloak which provides an additional phase to compensate the phase distortion introduced by a bump, thus restoring the reflection waves as if the incident waves impinge onto a flat mirror. The finite element simulation results demonstrate that an object can be hidden under these three kinds of waves with a single metasurface cloak.

  18. A metasurface carpet cloak for electromagnetic, acoustic and water waves.

    PubMed

    Yang, Yihao; Wang, Huaping; Yu, Faxin; Xu, Zhiwei; Chen, Hongsheng

    2016-01-01

    We propose a single low-profile skin metasurface carpet cloak to hide objects with arbitrary shape and size under three different waves, i.e., electromagnetic (EM) waves, acoustic waves and water waves. We first present a metasurface which can control the local reflection phase of these three waves. By taking advantage of this metasurface, we then design a metasurface carpet cloak which provides an additional phase to compensate the phase distortion introduced by a bump, thus restoring the reflection waves as if the incident waves impinge onto a flat mirror. The finite element simulation results demonstrate that an object can be hidden under these three kinds of waves with a single metasurface cloak. PMID:26822429

  19. Incorporating Hydroepidemiology into the Epidemia Malaria Early Warning System

    NASA Astrophysics Data System (ADS)

    Wimberly, M. C.; Merkord, C. L.; Henebry, G. M.; Senay, G. B.

    2014-12-01

    Early warning of the timing and locations of malaria epidemics can facilitate the targeting of resources for prevention and emergency response. In response to this need, we are developing the Epidemic Prognosis Incorporating Disease and Environmental Monitoring for Integrated Assessment (EPIDEMIA) computer system. EPIDEMIA incorporates software for capturing, processing, and integrating environmental and epidemiological data from multiple sources; data assimilation techniques that continually update models and forecasts; and a web-based interface that makes the resulting information available to public health decision makers. The system will enable forecasts that incorporate lagged responses to environmental risk factors as well as information about recent trends in malaria cases. Because the egg, larval, and pupal stages of mosquito development occur in aquatic habitats, information about the spatial and temporal distributions of stagnant water bodies is critical for modeling malaria risk. Potential sources of hydrological data include satellite-derived rainfall estimates, evapotranspiration (ET) calculated using a simplified surface energy balance model, and estimates of soil moisture and fractional water cover from passive microwave radiometry. We used partial least squares regression to analyze and visualize seasonal patterns of these variables in relation to malaria cases using data from 49 districts in the Amhara region of Ethiopia. Seasonal patterns of rainfall were strongly associated with the incidence and seasonality of malaria across the region, and model fit was improved by the addition of remotely-sensed ET and soil moisture variables. The results highlight the importance of remotely-sensed hydrological data for modeling malaria risk in this region and emphasize the value of an ensemble approach that utilizes multiple sources of information about precipitation and land surface wetness. These variables will be incorporated into the forecasting models at

  20. 14 CFR 253.5 - Notice of incorporated terms.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... contract, passengers may inspect the full text of each term incorporated by reference at the carrier's... service the full text of each such incorporated term; (b) The incorporated terms may include...

  1. 14 CFR 253.5 - Notice of incorporated terms.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... contract, passengers may inspect the full text of each term incorporated by reference at the carrier's... service the full text of each such incorporated term; (b) The incorporated terms may include...

  2. 14 CFR 253.5 - Notice of incorporated terms.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... contract, passengers may inspect the full text of each term incorporated by reference at the carrier's... service the full text of each such incorporated term; (b) The incorporated terms may include...

  3. Wave Power Demonstration Project at Reedsport, Oregon

    SciTech Connect

    Mekhiche, Mike; Downie, Bruce

    2013-10-21

    Ocean wave power can be a significant source of large‐scale, renewable energy for the US electrical grid. The Electrical Power Research Institute (EPRI) conservatively estimated that 20% of all US electricity could be generated by wave energy. Ocean Power Technologies, Inc. (OPT), with funding from private sources and the US Navy, developed the PowerBuoy to generate renewable energy from the readily available power in ocean waves. OPT's PowerBuoy converts the energy in ocean waves to electricity using the rise and fall of waves to move the buoy up and down (mechanical stroking) which drives an electric generator. This electricity is then conditioned and transmitted ashore as high‐voltage power via underwater cable. OPT's wave power generation system includes sophisticated techniques to automatically tune the system for efficient conversion of random wave energy into low cost green electricity, for disconnecting the system in large waves for hardware safety and protection, and for automatically restoring operation when wave conditions normalize. As the first utility scale wave power project in the US, the Wave Power Demonstration Project at Reedsport, OR, will consist of 10 PowerBuoys located 2.5 miles off the coast. This U.S. Department of Energy Grant funding along with funding from PNGC Power, an Oregon‐based electric power cooperative, was utilized for the design completion, fabrication, assembly and factory testing of the first PowerBuoy for the Reedsport project. At this time, the design and fabrication of this first PowerBuoy and factory testing of the power take‐off subsystem are complete; additionally the power take‐off subsystem has been successfully integrated into the spar.

  4. Standing gravitational waves from domain walls

    SciTech Connect

    Gogberashvili, Merab; Myrzakul, Shynaray; Singleton, Douglas

    2009-07-15

    We construct a plane symmetric, standing gravitational wave for a domain wall plus a massless scalar field. The scalar field can be associated with a fluid which has the properties of 'stiff' matter, i.e., matter in which the speed of sound equals the speed of light. Although domain walls are observationally ruled out in the present era, the solution has interesting features which might shed light on the character of exact nonlinear wave solutions to Einstein's equations. Additionally this solution may act as a template for higher dimensional 'brane-world' model standing waves.

  5. Electrostatic waves in the magnetosphere of Uranus

    NASA Technical Reports Server (NTRS)

    Kurth, W. S; Gurnett, D. A.; Barbosa, D. D.; Scarf, F. L.

    1987-01-01

    Observations of electrostatic waves in the magnetosphere of Uranus are discussed with attention focused on the Bernstein emissions. The most intense Bernstein waves were observed near the magnetic equator of the planet, even though the tilt of the Uranian magnetic moment is very large relative to the rotational axis. In addition to the Bernstein modes, a number of highly sporadic emissions were detected in the vicinity of the Miranda L shell.

  6. Spiral waves in a model of myocardium

    NASA Astrophysics Data System (ADS)

    Tyson, John J.; Keener, James P.

    1987-11-01

    Myocardial tissue is an excitable medium through which propagate waves of electrical stimulation and muscular contraction. In addition to radially expanding waves of neuromuscular activity characterizing the normal heartbeat, myocardial tissue may also support high frequency, rotating spiral waves of activity which are associated with cardiac pathologies (flutter and fibrillation). Recently Pertsov, Ermakova and Panfilov have presented a numerical study of rotating spiral waves in a two-dimensional excitable medium modeled on the FitzHugh-Nagumo equations, suitably modified to reflect the electrical properties of myocardium. We show that some of their principal numerical results can be reproduced in quantitative detail by a general theory of rotating spiral waves in excitable media. The critical ingredients of our theory are the dispersion of nonlinear plane waves and the effects of curvature on the propagation of wave fronts in two-dimensional media. The close comparison of our analytical results with numerical simulations of the full reaction-diffusion equations lends credence to our theoretical description of spiral waves in excitable media.

  7. Mucosal Wave Measurement and Visualization Techniques

    PubMed Central

    Krausert, Christopher R.; Olszewski, Aleksandra E.; Taylor, Lindsay N.; McMurray, James S.; Dailey, Seth H.; Jiang, Jack J.

    2010-01-01

    Organized vibration of the vocal folds is critical to high quality voice production. When the vocal folds oscillate, the superficial tissue of the vocal fold is displaced in a wave-like fashion, creating the so called “mucosal wave”. Because the mucosal wave is dependent on vocal fold structure, physical alterations of that structure cause mucosal wave abnormalities. Visualization and quantification of mucosal wave properties have become useful parameters in diagnosing and managing vocal fold pathology. Mucosal wave measurement provides information about vocal fold characteristics that cannot be determined with other assessment techniques. Here, we discuss the benefits, disadvantages, and clinical applicability of the different mucosal wave measurement techniques, such as electroglottography (EGG), photoglottography (PGG), and ultrasound and visualization techniques that include videokymography (VKG), stroboscopy, and high-speed digital imaging (HSDI). The various techniques and their specific uses are reviewed with the intention of helping researchers and clinicians choose a method for a given situation and understand its limitations as well as its potential applications. Recent applications of these techniques for quantitative assessment demonstrate that additional research must be conducted to realize the full potential of these tools. Evaluations of existing research and recommendations for future research are given to promote both the quantitative study of the mucosal wave through accurate and standardized measurement of mucosal wave parameters and the development of reliable methods with which physicians can diagnose vocal disorders. PMID:20471798

  8. Wave turbulence in annular wave tank

    NASA Astrophysics Data System (ADS)

    Onorato, Miguel; Stramignoni, Ettore

    2014-05-01

    We perform experiments in an annular wind wave tank at the Dipartimento di Fisica, Universita' di Torino. The external diameter of the tank is 5 meters while the internal one is 1 meter. The tank is equipped by two air fans which can lead to a wind of maximum 5 m/s. The present set up is capable of studying the generation of waves and the development of wind wave spectra for large duration. We have performed different tests including different wind speeds. For large wind speed we observe the formation of spectra consistent with Kolmogorv-Zakharov predictions.

  9. Partial Wave Dispersion Relations: Application to Electron-Atom Scattering

    NASA Technical Reports Server (NTRS)

    Temkin, A.; Drachman, Richard J.

    1999-01-01

    In this Letter we propose the use of partial wave dispersion relations (DR's) as the way of solving the long-standing problem of correctly incorporating exchange in a valid DR for electron-atom scattering. In particular a method is given for effectively calculating the contribution of the discontinuity and/or poles of the partial wave amplitude which occur in the negative E plane. The method is successfully tested in three cases: (i) the analytically solvable exponential potential, (ii) the Hartree potential, and (iii) the S-wave exchange approximation for electron-hydrogen scattering.

  10. Simulation of the collapse and dissipation of Langmuir wave packets

    NASA Technical Reports Server (NTRS)

    Newman, D. L.; Winglee, R. M.; Robinson, P. A.; Glanz, J.; Goldman, M. V.

    1990-01-01

    Particle-in-cell (PIC) simulations and Zakharov's partial differential equations (PDEs) are used to investigate the collapse of isolated Langmuir wave packets in two dimensions. Collapse thresholds are determined numerically, and the roles of enhanced Langmuir wave damping and nonlinearities not included in the standard Zakharov equations are discussed. The Langmuir wave and ion dynamics in PIC simulations are compared with the predictions of PDE simulations incorporating enhanced Langmuir damping. Electron heating and coherent acceleration in the PIC simulations are discussed and compared with predictions of the transit-time theory.

  11. High-efficiency, 200 watt, 12-gigahertz traveling wave tube

    NASA Technical Reports Server (NTRS)

    Kosmahl, H. G.; Mcnary, B. D.; Sauseng, O.

    1974-01-01

    Design and performance of a highly efficient experimental 200-watt traveling wave tube for space communications are described. The tube uses a coupled cavity slow wave structure with periodic permanent magnet focusing. A two-step velocity taper is incorporated in the slow wave structure for velocity resynchronization with the modulated beam. The spent beam is reconditioned in a refocusing section before it is collected in a novel multistage depressed collector. The collector is radiation cooled and heat insulated from the tube body. At saturation the tube provides peak output power of 240 watts with a 35-db gain and an overall maximum efficiency of 56 percent.

  12. Interaction and generation of small-scale waves by medium-scale waves in the MLT region.

    NASA Astrophysics Data System (ADS)

    Heale, C. J.; Snively, J. B.

    2015-12-01

    Interactions between gravity waves of different scales are frequent in the mesosphere and lower thermosphere (MLT) region of Earth's atmosphere. Recent coordinated observational studies [e.g., Fritts et al. 2014, Taylor et al. 2015, Bossert et al. 2015 ] have identified numerous cases where small-scale waves (~10s km wavelength, minute periods) are found to be propagating within strong medium-scale wave fields (~100s km wavelength and intrinsic periods of approximately hours). Despite this, it is unclear to what extent the small-scale waves are generated from the same source, are ambient in the atmosphere as generated by other sources, or are generated in-situ by the medium-scale wave and its interactions. A 2D compressible, nonlinear model is used to simulate cases of (1) the refractive effects of medium scale wave-like wind and temperature fields in addition to (2) the full dynamic interactions between small scale and medium scale waves under realistic atmospheric conditions. We investigate possible mechanisms for the medium scale wave to provide favorable regions of propagation for smaller scale waves from other sources in contrast to scenarios favoring in-situ wave generation or the generation of smaller-scale wavelike features. We also examine the propagation of small-scale waves generated from the same source location as the medium-scale waves, and how the propagation characteristics of waves determine which parts of the gravity wave spectrum may be susceptible to possible interactions. Small scale waves are shown to have a significant impact on the momentum and energy budget of the MLT through dissipation, filtering, and instability mechanisms [e.g. Fritts and Alexander 2003, Fritts et al. 2014]. Understanding and separating the roles of larger scale waves in refracting, interacting with, or generating smaller scale waves will be crucial in predicting the location and distribution of small-scale wave energy and momentum depositions and the resulting local

  13. A Reaction-Diffusion Model of Cholinergic Retinal Waves

    PubMed Central

    Lansdell, Benjamin; Ford, Kevin; Kutz, J. Nathan

    2014-01-01

    Prior to receiving visual stimuli, spontaneous, correlated activity in the retina, called retinal waves, drives activity-dependent developmental programs. Early-stage waves mediated by acetylcholine (ACh) manifest as slow, spreading bursts of action potentials. They are believed to be initiated by the spontaneous firing of Starburst Amacrine Cells (SACs), whose dense, recurrent connectivity then propagates this activity laterally. Their inter-wave interval and shifting wave boundaries are the result of the slow after-hyperpolarization of the SACs creating an evolving mosaic of recruitable and refractory cells, which can and cannot participate in waves, respectively. Recent evidence suggests that cholinergic waves may be modulated by the extracellular concentration of ACh. Here, we construct a simplified, biophysically consistent, reaction-diffusion model of cholinergic retinal waves capable of recapitulating wave dynamics observed in mice retina recordings. The dense, recurrent connectivity of SACs is modeled through local, excitatory coupling occurring via the volume release and diffusion of ACh. In addition to simulation, we are thus able to use non-linear wave theory to connect wave features to underlying physiological parameters, making the model useful in determining appropriate pharmacological manipulations to experimentally produce waves of a prescribed spatiotemporal character. The model is used to determine how ACh mediated connectivity may modulate wave activity, and how parameters such as the spontaneous activation rate and sAHP refractory period contribute to critical wave size variability. PMID:25474327

  14. Energy Efficient Electrochromic Windows Incorporating Ionic Liquids

    SciTech Connect

    Cheri Boykin; James Finley; Donald Anthony; Julianna Knowles; Richard Markovic; Michael Buchanan; Mary Ann Fuhry; Lisa Perrine

    2008-11-30

    One approach to increasing the energy efficiency of windows is to control the amount of solar radiation transmitted through a window by using electrochromic technology. What is unique about this project is that the electrochromic is based on the reduction/oxidation reactions of cathodic and anodic organic semi-conducting polymers using room temperature ionic liquids as ion transport electrolytes. It is believed that these types of coatings would be a lower cost alternative to traditional all inorganic thin film based electrochromic technologies. Although there are patents1 based on the proposed technology, it has never been reduced to practice and thoroughly evaluated (i.e. durability and performance) in a window application. We demonstrate that by using organic semi-conductive polymers, specific bands of the solar spectrum (specifically visible and near infrared) can be targeted for electrochemical variable transmittance responsiveness. In addition, when the technology is incorporated into an insulating glass unit, the energy parameters such as the solar heat gain coefficient and the light to solar gain ratio are improved over that of a typical insulating glass unit comprised of glass with a low emissivity coating. A minimum of {approx}0.02 quads of energy savings per year with a reduction of carbon emissions for electricity of {approx}320 MKg/yr benefit is achieved over that of a typical insulating glass unit including a double silver low-E coating. Note that these values include a penalty in the heating season. If this penalty is removed (i.e. in southern climates or commercial structures where cooling is predominate year-round) a maximum energy savings of {approx}0.05 quad per year and {approx}801 MKg/yr can be achieved over that of a typical insulating glass unit including a double silver low-E coating. In its current state, the technology is not durable enough for an exterior window application. The primary downfall is that the redox chemistry fails to

  15. Incorporation of TGF-beta 3 within collagen-hyaluronic acid scaffolds improves their chondrogenic potential.

    PubMed

    Matsiko, Amos; Levingstone, Tanya J; Gleeson, John P; O'Brien, Fergal J

    2015-06-01

    Incorporation of therapeutics in the form of growth factors within biomaterials can enhance their biofunctionality. Two methods of incorporating transforming growth factor-beta 3 within collagen-hyaluronic acid scaffolds are described, markedly improving mesenchymal stem cell-mediated chondrogenic differentiation and matrix production. Such scaffolds offer control over the release of therapeutics, demonstrating their potential for repair of complex chondral defects requiring additional stimuli.

  16. Incorporation of Helium Demixing in Interior Structure Models of Saturn

    NASA Astrophysics Data System (ADS)

    Tian, Bob; Stanley, Sabine; Valencia, Diana

    2015-04-01

    Experiments and ab initio calculations of hydrogen-helium mixtures predict a phase separation at pressure-temperature conditions relevant to Saturn's interior. At depths where this occurs, droplets of helium form out of the mixture and sink towards the deep interiors where it re-mixes again, thereby depleting the helium above the layer over time while enriching the concentration below the layer. In dynamo modelling, the axisymmetric nature of Saturn's magnetic field is so far best explained by the inclusion of a stably stratified layer just below the depth at which hydrogen metallizes (approximately 0.65RS). Stable stratification at that depth could occur if the compositional gradients produced by the helium rain process described above is great enough to suppress convection in the de-mixing layers. Thus, we first developed a range of interior structure models consistent with available constraints of the gravity field and atmospheric composition. The hydrogen-helium de-mixing curve was then incorporated in calculations of some of these models to assess its feasibility in compositionally stratifying the top of the dynamo source region. We found that when helium rain is taken into account, a stably stratified layer approximately 0.1 - 0.15RS in thickness can exist atop the dynamo source region, consistent with thicknesses needed in dynamo models to axisymmetrize the observable magnetic field. Furthermore, inertial gravity waves could be excited in such thick stably stratified regions. These may be detectable by asteroseismology techniques, or by analysis of wave modes' gravitational interaction with Saturn's ring particles. Thus, profiles of sound speed and Brunt-Vaisala frequencies were also calculated for all of the interior structures models studied to be used for comparison with possible seismic studies in the future.

  17. Waves of energy

    SciTech Connect

    Smith, F.G.W.; Charlier, R.H.

    1981-05-01

    Possible means for harnessing the energy contained in ocean waves are considered. Problems associated with the low-grade nature of wave energy and the rate at which wave crests approach are pointed out, and simple devices already in use for the supply of energy to bell buoys, whistle buoys and lighted buoys are noted. Attention is then given to wave energy conversion systems based on the focusing of waves onto a narrow ramp leading to a reservoir from which water is released to power a turbine generator: a slightly submerged circular shell which directs waves into its center cavity where waves act to turn a turbine (the Dam-Atoll), a long vertical pipe with an internal valve allowing water to move in an upward direction (the Isaacs wave-energy pump), a turbine located at the bottom of an open-topped pipe (the Masuda buoy), a completely submerged closed air chamber from which runs a large pipe open to the sea, a wave piston which acts by the compression of air to drive a turbine, a massive structure with upper and lower reservoirs (the Russel rectifier), and devices which consist of floating or submerged objects which transfer wave energy to pumps (the Salter duck and Cockerell raft). It is concluded that although wave-powered generators are not likely to become competitive in the near future or provide more than a small portion of world demand, they may be found useful under special conditions.

  18. Waves of energy

    NASA Astrophysics Data System (ADS)

    Smith, F. G. W.; Charlier, R. H.

    1981-06-01

    Possible means for harnessing the energy contained in ocean waves are considered. Problems associated with the low-grade nature of wave energy and the rate at which wave crests approach are pointed out, and simple devices already in use for the supply of energy to bell buoys, whistle buoys and lighted buoys are noted. Attention is then given to wave energy conversion systems based on the focusing of waves onto a narrow ramp leading to a reservoir from which water is released to power a turbine generator; a slightly submerged circular shell which directs waves into its center cavity where waves act to turn a turbine (the Dam-Atoll); a long vertical pipe with an internal valve allowing water to move in an upward direction (the Isaacs wave-energy pump); a turbine located at the bottom of an open-topped pipe (the Masuda buoy); a completely submerged closed air chamber from which runs a large pipe open to the sea; a wave piston which acts by the compression of air to drive a turbine; a massive structure with upper and lower reservoirs (the Russel rectifier); and devices which consist of floating or submerged objects which transfer wave energy to pumps (the Salter duck and Cockerell raft.) It is concluded that although wave-powered generators are not likely to become competitive in the near future or provide more than a small portion of world demand, they may be found useful under special conditions.

  19. Bound infragravity waves

    NASA Astrophysics Data System (ADS)

    Okihiro, Michele; Guza, R. T.; Seymour, R. J.

    1992-07-01

    Model predictions of bound (i.e., nonlinearly forced by and coupled to wave groups) infragravity wave energy are compared with about 2 years of observations in 8- to 13-m depths at Imperial Beach, California, and Barbers Point, Hawaii. Frequency-directional spectra of free waves at sea and swell frequencies, estimated with a small array of four pressure sensors, are used to predict the bound wave spectra below 0.04 Hz. The predicted total bound wave energy is always less than the observed infragravity energy, and the underprediction increases with increasing water depth and especially with decreasing swell energy. At most half, and usually much less, of the observed infragravity energy is bound. Bound wave spectra are also predicted with data from a single wave gage in 183-m depth at Point Conception, California, and the assumption of unidirectional sea and swell. Even with energetic swell, less than 10% of the total observed infragravity energy in 183-m depth is bound. Free waves, either leaky or edge waves, are more energetic than bound waves at both the shallow and deep sites. The low level of infragravity energy observed in 183-m depth compared with 8- to 13-m depths, with similarly moderate sea and swell energy, suggests that leaky (and very high-mode edge) waves contribute less than 10% of the infragravity energy in 8-13 m. Most of the free infragravity energy in shallow water is refractively trapped and does not reach deep water.

  20. Influence of artificially generated air bubbles on a wave breaking

    NASA Astrophysics Data System (ADS)

    Merkoune, D.; Ezersky, A.; Abcha, N.; Amine, F.; Mouazé, D.

    2011-12-01

    We report experimental results on influence of air bubbles curtain on wave breaking. It was found that position of wave breaking point depends on bubble concentration in water. It was revealed that the effect of wave breaking is very sensitive to the concentration of air bubbles which are situated near free surface of water. We showed that small concentration of artificially created bubbles do not lead to additional dissipation of energy in surface waves but change sufficiently the position of breaking point. This phenomenon could synchronize the breaking of irregular surface waves in the ocean and lead to the generation of spatially inhomogeneous turbulence in the upper layer of the ocean.

  1. Teleseismic S wave microseisms

    NASA Astrophysics Data System (ADS)

    Nishida, Kiwamu; Takagi, Ryota

    2016-08-01

    Although observations of microseisms excited by ocean swells were firmly established in the 1940s, the source locations remain difficult to track. Delineation of the source locations and energy partition of the seismic wave components are key to understanding the excitation mechanisms. Using a seismic array in Japan, we observed both P and S wave microseisms excited by a severe distant storm in the Atlantic Ocean. Although nonlinear forcing of an ocean swell with a one-dimensional Earth model can explain P waves and vertically polarized S waves (SV waves), it cannot explain horizontally polarized S waves (SH waves). The precise source locations may provide a new catalog for exploring Earth’s interior.

  2. Blast wave energy diagnostic.

    PubMed

    Tierney, Thomas E; Tierney, Heidi E; Idzorek, George C; Watt, Robert G; Peterson, Robert R; Peterson, Darrell L; Fryer, Christopher L; Lopez, Mike R; Jones, Michael C; Sinars, Daniel; Rochau, Gregory A; Bailey, James E

    2008-10-01

    The distance radiation waves that supersonically propagate in optically thick, diffusive media are energy sensitive. A blast wave can form in a material when the initially diffusive, supersonic radiation wave becomes transonic. Under specific conditions, the blast wave is visible with radiography as a density perturbation. [Peterson et al., Phys. Plasmas 13, 056901 (2006)] showed that the time-integrated drive energy can be measured using blast wave positions with uncertainties less than 10% at the Z Facility. In some cases, direct measurements of energy loss through diagnostic holes are not possible with bolometric and x-ray radiometric diagnostics. Thus, radiography of high compression blast waves can serve as a complementary technique that provides time-integrated energy loss through apertures. In this paper, we use blast waves to characterize the energy emerging through a 2.4 mm aperture and show experimental results in comparison to simulations. PMID:19044574

  3. Teleseismic S wave microseisms.

    PubMed

    Nishida, Kiwamu; Takagi, Ryota

    2016-08-26

    Although observations of microseisms excited by ocean swells were firmly established in the 1940s, the source locations remain difficult to track. Delineation of the source locations and energy partition of the seismic wave components are key to understanding the excitation mechanisms. Using a seismic array in Japan, we observed both P and S wave microseisms excited by a severe distant storm in the Atlantic Ocean. Although nonlinear forcing of an ocean swell with a one-dimensional Earth model can explain P waves and vertically polarized S waves (SV waves), it cannot explain horizontally polarized S waves (SH waves). The precise source locations may provide a new catalog for exploring Earth's interior. PMID:27563094

  4. Diffusion Driven Combustion Waves in Porous Media

    NASA Technical Reports Server (NTRS)

    Aldushin, A. P.; Matkowsky, B. J.

    2000-01-01

    the wave velocity. In addition to the reaction and diffusion layers, the uniformly propagating wave structure includes a layer with a pressure gradient, where the gas motion is induced by the production or consumption of the gas in the reaction as well as by thermal expansion of the gas. The width of this zone determines the scale of the combustion wave in the porous medium.

  5. Incorporation of continuous student assessment into lectures in engineering education

    NASA Astrophysics Data System (ADS)

    Myllymäki, S.

    2013-08-01

    A continuous student assessment system was incorporated into an advanced microelectronic course. This study investigated the relationship between the continuous assessment system based on home exams and individual student achievement. The perspective was based on the learning frameworks of the social constructivist theory. Six fourth-year engineering students participated in the study, which covered 13 lectures and 5 home exams. Feedback sessions concerning the particular exam were held after every exam. Correlations between the exams, the feedback, and individual student achievement were computed. The results indicated a positive correlation between continuous assessment and student achievement. Rather than being improved a lot, student achievement stabilised statistically at a higher level. Additionally, student's absence was very low (5%) despite the voluntary participation in the course. Continuous assessment realised with home exams induced two-way discussions between the teacher and the students. Unprompted, the students learned additional material and discussed it in the exam essays, confirming the principles of social constructivist theory.

  6. Incorporating Active Runway Crossings in Airport Departure Scheduling

    NASA Technical Reports Server (NTRS)

    Gupta, Gautam; Malik, Waqar; Jung, Yoon C.

    2010-01-01

    A mixed integer linear program is presented for deterministically scheduling departure and ar rival aircraft at airport runways. This method addresses different schemes of managing the departure queuing area by treating it as first-in-first-out queues or as a simple par king area where any available aircraft can take-off ir respective of its relative sequence with others. In addition, this method explicitly considers separation criteria between successive aircraft and also incorporates an optional prioritization scheme using time windows. Multiple objectives pertaining to throughput and system delay are used independently. Results indicate improvement over a basic first-come-first-serve rule in both system delay and throughput. Minimizing system delay results in small deviations from optimal throughput, whereas minimizing throughput results in large deviations in system delay. Enhancements for computational efficiency are also presented in the form of reformulating certain constraints and defining additional inequalities for better bounds.

  7. Additional Arctic observations improve weather and sea-ice forecasts for the Northern Sea Route

    NASA Astrophysics Data System (ADS)

    Inoue, Jun; Yamazaki, Akira; Ono, Jun; Dethloff, Klaus; Maturilli, Marion; Neuber, Roland; Edwards, Patti; Yamaguchi, Hajime

    2015-11-01

    During ice-free periods, the Northern Sea Route (NSR) could be an attractive shipping route. The decline in Arctic sea-ice extent, however, could be associated with an increase in the frequency of the causes of severe weather phenomena, and high wind-driven waves and the advection of sea ice could make ship navigation along the NSR difficult. Accurate forecasts of weather and sea ice are desirable for safe navigation, but large uncertainties exist in current forecasts, partly owing to the sparse observational network over the Arctic Ocean. Here, we show that the incorporation of additional Arctic observations improves the initial analysis and enhances the skill of weather and sea-ice forecasts, the application of which has socioeconomic benefits. Comparison of 63-member ensemble atmospheric forecasts, using different initial data sets, revealed that additional Arctic radiosonde observations were useful for predicting a persistent strong wind event. The sea-ice forecast, initialised by the wind fields that included the effects of the observations, skilfully predicted rapid wind-driven sea-ice advection along the NSR.

  8. Additional Arctic observations improve weather and sea-ice forecasts for the Northern Sea Route.

    PubMed

    Inoue, Jun; Yamazaki, Akira; Ono, Jun; Dethloff, Klaus; Maturilli, Marion; Neuber, Roland; Edwards, Patti; Yamaguchi, Hajime

    2015-01-01

    During ice-free periods, the Northern Sea Route (NSR) could be an attractive shipping route. The decline in Arctic sea-ice extent, however, could be associated with an increase in the frequency of the causes of severe weather phenomena, and high wind-driven waves and the advection of sea ice could make ship navigation along the NSR difficult. Accurate forecasts of weather and sea ice are desirable for safe navigation, but large uncertainties exist in current forecasts, partly owing to the sparse observational network over the Arctic Ocean. Here, we show that the incorporation of additional Arctic observations improves the initial analysis and enhances the skill of weather and sea-ice forecasts, the application of which has socioeconomic benefits. Comparison of 63-member ensemble atmospheric forecasts, using different initial data sets, revealed that additional Arctic radiosonde observations were useful for predicting a persistent strong wind event. The sea-ice forecast, initialised by the wind fields that included the effects of the observations, skilfully predicted rapid wind-driven sea-ice advection along the NSR. PMID:26585690

  9. Additional Arctic observations improve weather and sea-ice forecasts for the Northern Sea Route

    PubMed Central

    Inoue, Jun; Yamazaki, Akira; Ono, Jun; Dethloff, Klaus; Maturilli, Marion; Neuber, Roland; Edwards, Patti; Yamaguchi, Hajime

    2015-01-01

    During ice-free periods, the Northern Sea Route (NSR) could be an attractive shipping route. The decline in Arctic sea-ice extent, however, could be associated with an increase in the frequency of the causes of severe weather phenomena, and high wind-driven waves and the advection of sea ice could make ship navigation along the NSR difficult. Accurate forecasts of weather and sea ice are desirable for safe navigation, but large uncertainties exist in current forecasts, partly owing to the sparse observational network over the Arctic Ocean. Here, we show that the incorporation of additional Arctic observations improves the initial analysis and enhances the skill of weather and sea-ice forecasts, the application of which has socioeconomic benefits. Comparison of 63-member ensemble atmospheric forecasts, using different initial data sets, revealed that additional Arctic radiosonde observations were useful for predicting a persistent strong wind event. The sea-ice forecast, initialised by the wind fields that included the effects of the observations, skilfully predicted rapid wind-driven sea-ice advection along the NSR. PMID:26585690

  10. Additional Arctic observations improve weather and sea-ice forecasts for the Northern Sea Route.

    PubMed

    Inoue, Jun; Yamazaki, Akira; Ono, Jun; Dethloff, Klaus; Maturilli, Marion; Neuber, Roland; Edwards, Patti; Yamaguchi, Hajime

    2015-01-01

    During ice-free periods, the Northern Sea Route (NSR) could be an attractive shipping route. The decline in Arctic sea-ice extent, however, could be associated with an increase in the frequency of the causes of severe weather phenomena, and high wind-driven waves and the advection of sea ice could make ship navigation along the NSR difficult. Accurate forecasts of weather and sea ice are desirable for safe navigation, but large uncertainties exist in current forecasts, partly owing to the sparse observational network over the Arctic Ocean. Here, we show that the incorporation of additional Arctic observations improves the initial analysis and enhances the skill of weather and sea-ice forecasts, the application of which has socioeconomic benefits. Comparison of 63-member ensemble atmospheric forecasts, using different initial data sets, revealed that additional Arctic radiosonde observations were useful for predicting a persistent strong wind event. The sea-ice forecast, initialised by the wind fields that included the effects of the observations, skilfully predicted rapid wind-driven sea-ice advection along the NSR.

  11. Design of the NASA Lewis 4-Port Wave Rotor Experiment

    NASA Technical Reports Server (NTRS)

    Wilson, Jack

    1997-01-01

    Pressure exchange wave rotors, used in a topping stage, are currently being considered as a possible means of increasing the specific power, and reducing the specific fuel consumption of gas turbine engines. Despite this interest, there is very little information on the performance of a wave rotor operating on the cycle (i.e., set of waves) appropriate for use in a topping stage. One such cycle, which has the advantage of being relatively easy to incorporate into an engine, is the four-port cycle. Consequently, an experiment to measure the performance of a four-port wave rotor for temperature ratios relevant to application as a topping cycle for a gas turbine engine has been designed and built at NASA Lewis. The design of the wave rotor is described, together with the constraints on the experiment.

  12. Remote Sensing Characteristics of Wave Breaking Rollers

    NASA Astrophysics Data System (ADS)

    Haller, M. C.; Catalan, P.

    2006-12-01

    The wave roller has a primary influence on the balances of mass and momentum in the surf zone (e.g. Svendsen, 1984; Dally and Brown, 1995; Ruessink et al., 2001). In addition, the roller area and its angle of inclination on the wave front are important quantities governing the dissipation rates in breaking waves (e.g Madsen et al., 1997). Yet, there have been very few measurements published of individual breaking wave roller geometries in shallow water. A number of investigators have focused on observations of the initial jet-like motion at the onset of breaking before the establishment of the wave roller (e.g. Basco, 1985; Jansen, 1986), while Govender et al. (2002) provide observations of wave roller vertical cross-sections and angles of inclination for a pair of laboratory wave conditions. Nonetheless, presently very little is known about the growth, evolution, and decay of this aerated region of white water as it propagates through the surf zone; mostly due to the inherent difficulties in making the relevant observations. The present work is focused on analyzing observations of the time and space scales of individual shallow water breaking wave rollers as derived from remote sensing systems. Using a high-resolution video system in a large-scale laboratory facility, we have obtained detailed measurements of the growth and evolution of the wave breaking roller. In addition, by synchronizing the remote video with in-situ wave gages, we are able to directly relate the video intensity signal to the underlying wave shape. Results indicate that the horizontal length scale of breaking wave rollers differs significantly from the previous observations of Duncan (1981), which has been a traditional basis for roller model parameterizations. The overall approach to the video analysis is new in the sense that we concentrate on individual breaking waves, as opposed to the more commonly used time-exposure technique. In addition, a new parameter of interest, denoted Imax, is

  13. Toxicity of sediment-incorporated drilling fluids

    SciTech Connect

    Clark, J.R.; Patrick, J.M.

    1987-01-01

    The 24, 96, or 168-h LC50s of four used drilling fluids or barite incorporated into sediment were determined in toxicity tests with lancelets (Branchiostoma caribaeum), a benthic chordate. The number of lancelets that did not burrow into contaminated sediments was used to calculate EC50s at the same times that LC50s were determined. Observations of the burrowing behavior allowed quantitation of effects after 24-h exposures to each of the drilling fluids whereas lancelet mortality was sufficient to calculate 24-h LC50s for only one drilling fluid. Drilling fluids were less toxic to lancelets when incorporated into sediments than to mysids (Mysidopsis bahia) or benthic invertebrate communities in water-column exposures.

  14. Incorporating Nonchemical Stressors Into Cumulative Risk Assessments

    PubMed Central

    Rider, Cynthia V.; Dourson, Michael L.; Hertzberg, Richard C.; Mumtaz, Moiz M.; Price, Paul S.; Simmons, Jane Ellen

    2012-01-01

    The role of nonchemical stressors in modulating the human health risk associated with chemical exposures is an area of increasing attention. On 9 March 2011, a workshop titled “Approaches for Incorporating Nonchemical Stressors into Cumulative Risk Assessment” took place during the 50th Anniversary Annual Society of Toxicology Meeting in Washington D.C. Objectives of the workshop included describing the current state of the science from various perspectives (i.e., regulatory, exposure, modeling, and risk assessment) and presenting expert opinions on currently available methods for incorporating nonchemical stressors into cumulative risk assessments. Herein, distinct frameworks for characterizing exposure to, joint effects of, and risk associated with chemical and nonchemical stressors are discussed. PMID:22345310

  15. Comparative Incorporation of PNA into DNA Nanostructures.

    PubMed

    Pedersen, Ronnie O; Kong, Jing; Achim, Catalina; LaBean, Thomas H

    2015-09-23

    DNA has shown great promise as a building material for self-assembling nanoscale structures. To further develop the potential of this technology, more methods are needed for functionalizing DNA-based nanostructures to increase their chemical diversity. Peptide nucleic acid (PNA) holds great promise for realizing this goal, as it conveniently allows for inclusion of both amino acids and peptides in nucleic acid-based structures. In this work, we explored incorporation of a positively charged PNA within DNA nanostructures. We investigated the efficiency of annealing a lysine-containing PNA probe with complementary, single-stranded DNA sequences within nanostructures, as well as the efficiency of duplex invasion and its dependence on salt concentration. Our results show that PNA allows for toehold-free strand displacement and that incorporation yield depends critically on binding site geometry. These results provide guidance for the design of PNA binding sites on nucleic acid nanostructures with an eye towards optimizing fabrication yield.

  16. Unsteadiness effects in wave-current interaction in the nearshore

    NASA Astrophysics Data System (ADS)

    Haller, Merrick; Phaksopa, Jitraporn; Ozkan-Haller, Tuba

    2016-04-01

    Typical analyses of wave-current interaction assume the current field to be quasi-stationary and the absolute wave frequency to be time invariant. However, theory tells us that unsteady currents will induce a time variation in the absolute frequency and wavenumber. In this work we first demonstrate, through a large-scale laboratory experiment, observations of absolute wave frequency modulations. The frequency modulations are shown to be caused by both unsteady water depth and unsteady currents due to the presence of low-frequency standing waves in large wave flume. These observations allow a unique verification of the theoretical predictions. New analytic solutions for the variations in frequency and wave height induced by the unsteady currents are then given via a perturbation analysis and the importance of this phenomenon in natural situations is discussed. Next, we perform a more sophisticated numerical analysis using a coupled model system consisting of the time-integrated Navier-Stokes equations and the wave-action-balance equation including wave breaking dissipation. The model setup again involves standing long waves in an enclosed basin but here the waves and currents are fully coupled. The standing long waves are driven by wave breaking of the incident regular wave field. The coupled numerical system is used to verify the findings from the analytic work regarding variations in absolute frequency. In addition, from this analysis both positive and negative feedbacks between waves and currents are identified and shown to depend on the normalized bed slope. Specifically, for small normalized slopes, the negative feedback reduces the magnitudes of the standing long waves, while on steep slopes the long waves are amplified. The feedback dynamics are shown to correlate with the surf beat similarity introduced by Baldock (2012). This parameter also helps to distinguish between the forcing mechanisms of bound wave release versus time-varying breakpoint forcing.

  17. Incorporation of squalene into rod outer segments

    SciTech Connect

    Keller, R.K.; Fliesler, S.J. )

    1990-08-15

    We have reported previously that squalene is the major radiolabeled nonsaponifiable lipid product derived from ({sup 3}H)acetate in short term incubations of frog retinas. In the present study, we demonstrate that newly synthesized squalene is incorporated into rod outer segments under similar in vitro conditions. We show further that squalene is an endogenous constituent of frog rod outer segment membranes; its concentration is approximately 9.5 nmol/mumol of phospholipid or about 9% of the level of cholesterol. Pulse-chase experiments with radiolabeled precursors revealed no metabolism of outer segment squalene to sterols in up to 20 h of chase. Taken together with our previous absolute rate studies, these results suggest that most, if not all, of the squalene synthesized by the frog retina is transported to rod outer segments. Synthesis of protein is not required for squalene transport since puromycin had no effect on squalene incorporation into outer segments. Conversely, inhibition of isoprenoid synthesis with mevinolin had no effect on the incorporation of opsin into the outer segment. These latter results support the conclusion that the de novo synthesis and subsequent intracellular trafficking of opsin and isoprenoid lipids destined for the outer segment occur via independent mechanisms.

  18. Incorporating OASIS into the Visiting Nurses Association.

    PubMed

    Clark, L L

    1998-01-01

    Beginning in 1994, the Visiting Nurses Association, Western Pennsylvania, began to investigate incorporating an outcome measurement system within its organization for the purposes of marketing quality results, benchmarking achievements, and defining quality of care for both internal and external review groups. In the fall of 1995, this agency was accepted into the Outcome Based Quality Improvement (OBQI) Demonstration Project, also known as the Medicare Quality Assurance Project, which the Health Care Financing Administration has funded for the purpose of measuring clinical and utilization outcomes in the home care arena. This article reviews the processes the agency used to develop and incorporate the entire OBQI process into its systems, including the incorporation of the Outcome Assessment Information Set (OASIS). The OASIS is a set of outcome measurement questions developed by Dr. Peter Shaughnessy at the Center for Health Policy Research in Denver. The process also includes training of staff and development of forms, point-of-care software with a vendor, and plans of action for improving outcomes that have been quantified through OBQI efforts.

  19. Fundamental formulae for wave-energy conversion.

    PubMed

    Falnes, Johannes; Kurniawan, Adi

    2015-03-01

    The time-average wave power that is absorbed from an incident wave by means of a wave-energy conversion (WEC) unit, or by an array of WEC units-i.e. oscillating immersed bodies and/or oscillating water columns (OWCs)-may be mathematically expressed in terms of the WEC units' complex oscillation amplitudes, or in terms of the generated outgoing (diffracted plus radiated) waves, or alternatively, in terms of the radiated waves alone. Following recent controversy, the corresponding three optional expressions are derived, compared and discussed in this paper. They all provide the correct time-average absorbed power. However, only the first-mentioned expression is applicable to quantify the instantaneous absorbed wave power and the associated reactive power. In this connection, new formulae are derived that relate the 'added-mass' matrix, as well as a couple of additional reactive radiation-parameter matrices, to the difference between kinetic energy and potential energy in the water surrounding the immersed oscillating WEC array. Further, a complex collective oscillation amplitude is introduced, which makes it possible to derive, by a very simple algebraic method, various simple expressions for the maximum time-average wave power that may be absorbed by the WEC array. The real-valued time-average absorbed power is illustrated as an axisymmetric paraboloid defined on the complex collective-amplitude plane. This is a simple illustration of the so-called 'fundamental theorem for wave power'. Finally, the paper also presents a new derivation that extends a recently published result on the direction-average maximum absorbed wave power to cases where the WEC array's radiation damping matrix may be singular and where the WEC array may contain OWCs in addition to oscillating bodies.

  20. Fundamental formulae for wave-energy conversion

    PubMed Central

    Falnes, Johannes; Kurniawan, Adi

    2015-01-01

    The time-average wave power that is absorbed from an incident wave by means of a wave-energy conversion (WEC) unit, or by an array of WEC units—i.e. oscillating immersed bodies and/or oscillating water columns (OWCs)—may be mathematically expressed in terms of the WEC units' complex oscillation amplitudes, or in terms of the generated outgoing (diffracted plus radiated) waves, or alternatively, in terms of the radiated waves alone. Following recent controversy, the corresponding three optional expressions are derived, compared and discussed in this paper. They all provide the correct time-average absorbed power. However, only the first-mentioned expression is applicable to quantify the instantaneous absorbed wave power and the associated reactive power. In this connection, new formulae are derived that relate the ‘added-mass’ matrix, as well as a couple of additional reactive radiation-parameter matrices, to the difference between kinetic energy and potential energy in the water surrounding the immersed oscillating WEC array. Further, a complex collective oscillation amplitude is introduced, which makes it possible to derive, by a very simple algebraic method, various simple expressions for the maximum time-average wave power that may be absorbed by the WEC array. The real-valued time-average absorbed power is illustrated as an axisymmetric paraboloid defined on the complex collective-amplitude plane. This is a simple illustration of the so-called ‘fundamental theorem for wave power’. Finally, the paper also presents a new derivation that extends a recently published result on the direction-average maximum absorbed wave power to cases where the WEC array's radiation damping matrix may be singular and where the WEC array may contain OWCs in addition to oscillating bodies. PMID:26064612

  1. Diffuse scattered field of elastic waves from randomly rough surfaces using an analytical Kirchhoff theory

    NASA Astrophysics Data System (ADS)

    Shi, F.; Lowe, M. J. S.; Xi, X.; Craster, R. V.

    2016-07-01

    We develop an elastodynamic theory to predict the diffuse scattered field of elastic waves by randomly rough surfaces, for the first time, with the aid of the Kirchhoff approximation (KA). Analytical expressions are derived incorporating surface statistics, to represent the expectation of the angular distribution of the diffuse intensity for different modes. The analytical solutions are successfully verified with numerical Monte Carlo simulations, and also validated by comparison with experiments. We then apply the theory to quantitatively investigate the effects of the roughness and the shear-to-compressional wave speed ratio on the mode conversion and the scattering intensity, from low to high roughness within the valid region of KA. Both the direct and the mode converted intensities are significantly affected by the roughness, which leads to distinct scattering patterns for different wave modes. The mode conversion effect is very strong around the specular angle and it is found to increase as the surface appears to be more rough. In addition, the 3D roughness induced coupling between the out-of-plane shear horizontal (SH) mode and the in-plane modes is studied. The intensity of the SH mode is shown to be very sensitive to the out-of-plane correlation length, being influenced more by this than by the RMS value of the roughness. However, it is found that the depolarization pattern for the diffuse field is independent of the actual value of the roughness.

  2. Role of electromagnetically induced transparency in resonant four-wave-mixing schemes

    NASA Astrophysics Data System (ADS)

    Petch, J. C.; Keitel, C. H.; Knight, P. L.; Marangos, J. P.

    1996-01-01

    The effect of electromagnetically induced transparency in resonant four-wave-mixing schemes is investigated in an analysis that goes beyond perturbation theory in the coherent driving field. In addition we examine the case where the two-photon pump field is sufficiently strong to necessitate a nonperturbative treatment. This allows us to examine the cases where either one or both of the driving fields are strong. Phase matching is included in a plane-wave propagation treatment that matches the situation most likely to be encountered in actual experiments. The calculations are in part intended to model real experimental situations and thus incorporate driving and pump-field linewidths via the phase-diffusion model and Doppler broadening. With a strong pump-field laser, large enhancements in the efficiency of light generation occur at frequencies corresponding to the Autler-Townes satellites induced by the strong driving field. In this situation gain and high four-wave-mixing efficiency are simultaneously present, resulting in the production of a large intensity of coherent radiation.

  3. Effects of Emic Waves on the Outer Electron Radiation Belt.

    NASA Astrophysics Data System (ADS)

    Horne, R. B.; Kersten, T.; Glauert, S.; Meredith, N. P.; Fraser, B. J.; Grew, R. S.

    2014-12-01

    Over the last few years there has been substantial progress to incorporate wave-particle interactions into global simulation models of the radiation belts. Models of plasmaspheric hiss and whistler mode chorus make a huge impact on the variability of the relativistic electron flux. Electromagnetic Ion Cyclotron (EMIC) waves also cause electron loss from the radiation belts but their effectiveness has not been fully quantified. Here we present the results of simulations using a new chorus diffusion matrix and demonstrate that in principle the outer electron radiation belt can be formed by wave acceleration from a soft electron spectrum. We also describe a new model for EMIC waves. Wave data derived from the fluxgate magnetometer on CRRES was used to define the power spectrum as a function of geomagnetic activity, L* and magnetic local time for Hydrogen and Helium band waves. We show that wave power depends on activity as measured by AE and Kp. Using an assumed ion composition, and previously defined plasma density models the PADIE code was used to calculate bounce and drift averaged diffusion rates for EMIC waves and incorporated into the BAS Radiation Belt Model together with whistler mode chorus, plasmaspheric hiss and radial diffusion. Thus the model can be driven by a time sequence of Kp with appropriate boundary conditions. By simulating a 100 day period in 1990 we show that the model can produce electron flux up to energies of several MeV. When EMIC waves are included they cause a significant reduction in the electron flux for energies greater than 2 MeV but only for pitch angles lower than about 60 degrees. The simulations show that the distribution of electrons left behind in space looks like a pancake distribution at MeV energies. We show that EMIC waves cannot remove electrons at all pitch angles even at 30 MeV and are therefore unlikely to set an upper energy limit to the outer radiation belt.

  4. 33 CFR 101.310 - Additional communication devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... to augment communication, and may be one of the communication methods listed in a vessel security plan under part 104 of this subchapter. See 33 CFR part 164 for additional information on AIS device... SOLAS Chapter XI-2, Regulation 6 (Incorporated by reference, see § 101.115), may be used to...

  5. 33 CFR 101.310 - Additional communication devices.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to augment communication, and may be one of the communication methods listed in a vessel security plan under part 104 of this subchapter. See 33 CFR part 164 for additional information on AIS device... SOLAS Chapter XI-2, Regulation 6 (Incorporated by reference, see § 101.115), may be used to...

  6. Analysis of waves in the plasma guided by a periodical vane-type slow wave structure

    SciTech Connect

    Wu, T.J.; Kou, C.S.

    2005-10-01

    In this study, the dispersion relation has been derived to characterize the propagation of the waves in the plasma guided by a periodical vane-type slow wave structure. The plasma is confined by a quartz plate. Results indicate that there are two different waves in this structure. One is the plasma mode that originates from the plasma surface wave propagating along the interface between the plasma and the quartz plate, and the other is the guide mode that originally travels along the vane-type slow wave structure. In contrast to its original slow wave characteristics, the guide mode becomes a fast wave in the low-frequency portion of the passband, and there exists a cut-off frequency for the guide mode. The vane-type guiding structure has been shown to limit the upper frequency of the passband of the plasma mode, compared with that of the plasma surface wave. In addition, the passband of the plasma mode increases with the plasma density while it becomes narrower for the guide mode. The influences of the parameters of the guiding structure and plasma density on the propagation of waves are also presented.

  7. Water wave metamaterials

    NASA Astrophysics Data System (ADS)

    Petitjeans, Philippe; Palacios, Carmen; Maurel, Agnès; Pagneux, Vincent

    2012-11-01

    The phenomenon of water wave deviation in a bended wave-guide has been studied experimentally. We propose a theoretical analogy to electromagnetism, from which we derive the mathematical tools to design a water wave-deviator. To obtain the effect of metamaterial in the case of surface waves, one has to design a water-bed consisting of periodic layers of two different heights inclined with a specific angle with respect to the direction of propagation of waves. We designed and built (using rapid prototyping) deviators with progressively increasing angles of bending, and their homologue wave-guides with a flat bottom. The wave elevation was measured with good accuracy in time and in space by an optical method. Results show a good efficiency of the wave-deviator. The wavefront maintains its original inclination once the wave crosses the bend (in contrary to the wave-guide with a flat bottom), however departs from the predicted behavior as the wavefront advances. The analysis of harmonics shows a reduction of backwards reflection and a strong decrease in higher modes excitation after the bend. The results are optimistic and might open new possibilities; ultimately those regarding the cloaking of floating structures which could, in the future, be used for coastal protection.

  8. The Coordinated Ocean Wave Climate Project

    NASA Astrophysics Data System (ADS)

    Hemer, Mark; Dobrynin, Mikhail; Erikson, Li; Lionello, Piero; Mori, Nobuhito; Semedo, Alvaro; Wang, Xiaolan

    2016-04-01

    Future 21st Century changes in wind-wave climate have broad implications for marine and coastal infrastructure and ecosystems. Atmosphere-ocean general circulation models (GCM) are now routinely used for assessing and providing future projections of climatological parameters such as temperature and precipitation, but generally these provide no information on ocean wind-waves. To fill this information gap a growing number of studies are using GCM outputs and independently producing global and regional scale wind-wave climate projections. Furthermore, additional studies are actively coupling wind-wave dependent atmosphere-ocean exchanges into GCMs, to improve physical representation and quantify the impact of waves in the coupled climate system, and can also deliver wave characteristics as another variable in the climate system. To consolidate these efforts, understand the sources of variance between projections generated by different methodologies and International groups, and ultimately provide a robust picture of the role of wind-waves in the climate system and their projected changes, we present outcomes of the JCOMM supported Coordinated Ocean Wave Climate Project (COWCLIP). The objective of COWCLIP is twofold: to make community based ensembles of wave climate projections openly accessible, to provide the necessary information to support diligent marine and coastal impacts of climate change studies; and to understand the effects and feedback influences of wind-waves in the coupled ocean-atmosphere climate system. We will present the current status of COWCLIP, providing an overview of the objectives, analysis and results of the initial phase - now complete - and the progress of ongoing phases of the project.

  9. Cyanoethylated Compounds as Additives in Lithium/Lithium Ion Batteries

    SciTech Connect

    Nagasubramanian, Ganesan

    1998-05-08

    The power loss of lithium/lithium ion battery cells is significantly reduced, especially at low temperatures, when about 1% by weight of an additive is incorporated in the electrolyte layer of the cells. The usable additives are organic solvent soluble cyanoethylated polysaccharides and poly(vinyl alcohol). The power loss decrease results primarily from the decrease in the charge transfer resistance at the interface between the electrolyte and the cathode.

  10. Cyanoethylated compounds as additives in lithium/lithium batteries

    DOEpatents

    Nagasubramanian, Ganesan

    1999-01-01

    The power loss of lithium/lithium ion battery cells is significantly reduced, especially at low temperatures, when about 1% by weight of an additive is incorporated in the electrolyte layer of the cells. The usable additives are organic solvent soluble cyanoethylated polysaccharides and poly(vinyl alcohol). The power loss decrease results primarily from the decrease in the charge transfer resistance at the interface between the electrolyte and the cathode.

  11. Ion acoustic wave collapse via two-ion wave decay: 2D Vlasov simulation and theory

    NASA Astrophysics Data System (ADS)

    Chapman, Thomas; Berger, Richard; Banks, Jeffrey; Brunner, Stephan

    2015-11-01

    The decay of ion acoustic waves (IAWs) via two-ion wave decay may transfer energy from the electric field of the IAWs to the particles, resulting in a significant heating of resonant particles. This process has previously been shown in numerical simulations to decrease the plasma reflectivity due to stimulated Brillouin scattering. Two-ion wave decay is a fundamental property of ion acoustic waves that occurs over most if not all of the parameter space of relevance to inertial confinement fusion experiments, and can lead to a sudden collapse of IAWs. The treatment of all species kinetically, and in particular the electrons, is required to describe the decay process correctly. We present fully kinetic 2D+2V Vlasov simulations of IAWs undergoing decay to a highly nonlinear turbulent state using the code LOKI. The scaling of the decay rate with characteristic plasma parameters and wave amplitude is shown. A new theory describing two-ion wave decay in 2D, that incorporates key kinetic properties of the electrons, is presented and used to explain quantitatively for the first time the observed decay of IAWs. Work performed under auspices of U.S. DoE by LLNL, Contract DE-AC52-07NA2734. Funded by LDRD 15-ERD-038 and supported by LLNL Grand Challenge allocation.

  12. Magnetic field waves at Uranus

    NASA Technical Reports Server (NTRS)

    Smith, Charles W.; Goldstein, Melvyn L.; Lepping, Ronald P.; Mish, William H.; Wong, Hung K.

    1991-01-01

    The proposed research efforts funded by the UDAP grant to the BRI involve the study of magnetic field waves associated with the Uranian bow shock. This is a collaborative venture bringing together investigators at the BRI, Southwest Research Institute (SwRI), and Goddard Space Flight Center (GSFC). In addition, other collaborations have been formed with investigators granted UDAP funds for similar studies and with investigators affiliated with other Voyager experiments. These investigations and the corresponding collaborations are included in the report. The proposed effort as originally conceived included an examination of waves downstream from the shock within the magnetosheath. However, the observations of unexpected complexity and diversity within the upstream region have necessitated that we confine our efforts to those observations recorded upstream of the bow shock on the inbound and outbound legs of the encounter by the Voyager 2 spacecraft.

  13. Controls on flood and sediment wave propagation

    NASA Astrophysics Data System (ADS)

    Bakker, Maarten; Lane, Stuart N.; Costa, Anna; Molnar, Peter

    2015-04-01

    The understanding of flood wave propagation - celerity and transformation - through a fluvial system is of generic importance for flood forecasting/mitigation. In association with flood wave propagation, sediment wave propagation may induce local erosion and sedimentation, which will affect infrastructure and riparian natural habitats. Through analysing flood and sediment wave propagation, we gain insight in temporal changes in transport capacity (the flood wave) and sediment availability and transport (the sediment wave) along the river channel. Heidel (1956) was amongst the first to discuss the progressive lag of sediment concentration behind the corresponding flood wave based on field measurements. Since then this type of hysteresis has been characterized in a number of studies, but these were often based on limited amount of floods and measurement sites, giving insufficient insight into associated forcing mechanisms. Here, as part of a project concerned with the hydrological and geomorphic forcing of sediment transfer processes in alpine environments, we model the downstream propagation of short duration, high frequency releases of water and sediment (purges) from a flow intake in the Borgne d'Arolla River in south-west Switzerland. A total of >50 events were measured at 1 minute time intervals using pressure transducers and turbidity probes at a number of sites along the river. We show that flood and sediment wave propagation can be well represented through simple convection diffusion models. The models are calibrated/validated to describe the set of measured waves and used to explain the observed variation in wave celerity and diffusion. In addition we explore the effects of controlling factors including initial flow depth, flood height, flood duration, bed roughness, bed slope and initial sediment concentration, on the wave propagation processes. We show that the effects of forcing mechanisms on flood and sediment wave propagation will lead to different

  14. 46 CFR 61.03-1 - Incorporation by reference.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Incorporation by reference. 61.03-1 Section 61.03-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PERIODIC TESTS AND INSPECTIONS Incorporation of Standards § 61.03-1 Incorporation by reference. (a) Certain material is incorporated by reference into this part with...

  15. Geometric optics radome analysis wall incorporating effects of wall curvature

    NASA Astrophysics Data System (ADS)

    Kozakoff, Dennis J.

    1993-07-01

    In this research, a principal unmodeled error contributor in radome analysis is identified as the local plane approximation at the ray intercept point. An improved approach to modeling and computing the effects of the radome wall was developed which improves the radome wall transmission wall analysis in three respects: use of surface integration, utilization of a divergence factor (DF) to account for wall curvature, and incorporation of the effects of multiple refraction (MR). Modeling an incident plane wave on an external reference plane as an ensemble of Huygen's sources, geometric optics is used to trace the fields from the reference plane through the radome wall to a receiving monopulse antenna, where the wall transmissions on each ray are collected. The fact that the integration of a bundle of rays through the radome wall, as opposed to a single ray, more densely samples the curvature variation results in a more robust model. A DF derived from Snell's law for spherical shells accounts for the local wall curvature at the ray intercept point. To validate the approach, a microwave measurement setup was assembled around a network analyzer. Swept frequency data were obtained for similar monolithic wall dielectric panels but with different wall curvatures. Comparisons were then with measured data and the predictions of the model herein.

  16. Influence of and additives on acetylene detonation

    NASA Astrophysics Data System (ADS)

    Drakon, A.; Emelianov, A.; Eremin, A.

    2014-03-01

    The influence of and admixtures (known as detonation suppressors for combustible mixtures) on the development of acetylene detonation was experimentally investigated in a shock tube. The time-resolved images of detonation wave development and propagation were registered using a high-speed streak camera. Shock wave velocity and pressure profiles were measured by five calibrated piezoelectric gauges and the formation of condensed particles was detected by laser light extinction. The induction time of detonation development was determined as the moment of a pressure rise at the end plate of the shock tube. It was shown that additive had no influence on the induction time. For , a significant promoting effect was observed. A simplified kinetic model was suggested and characteristic rates of diacetylene formation were estimated as the limiting stage of acetylene polymerisation. An analysis of the obtained data indicated that the promoting species is atomic chlorine formed by pyrolysis, which interacts with acetylene and produces radical, initiating a chain mechanism of acetylene decomposition. The results of kinetic modelling agree well with the experimental data.

  17. Wave data processing toolbox manual

    USGS Publications Warehouse

    Sullivan, Charlene M.; Warner, John C.; Martini, Marinna A.; Lightsom, Frances S.; Voulgaris, George; Work, Paul

    2006-01-01

    Researchers routinely deploy oceanographic equipment in estuaries, coastal nearshore environments, and shelf settings. These deployments usually include tripod-mounted instruments to measure a suite of physical parameters such as currents, waves, and pressure. Instruments such as the RD Instruments Acoustic Doppler Current Profiler (ADCP(tm)), the Sontek Argonaut, and the Nortek Aquadopp(tm) Profiler (AP) can measure these parameters. The data from these instruments must be processed using proprietary software unique to each instrument to convert measurements to real physical values. These processed files are then available for dissemination and scientific evaluation. For example, the proprietary processing program used to process data from the RD Instruments ADCP for wave information is called WavesMon. Depending on the length of the deployment, WavesMon will typically produce thousands of processed data files. These files are difficult to archive and further analysis of the data becomes cumbersome. More imperative is that these files alone do not include sufficient information pertinent to that deployment (metadata), which could hinder future scientific interpretation. This open-file report describes a toolbox developed to compile, archive, and disseminate the processed wave measurement data from an RD Instruments ADCP, a Sontek Argonaut, or a Nortek AP. This toolbox will be referred to as the Wave Data Processing Toolbox. The Wave Data Processing Toolbox congregates the processed files output from the proprietary software into two NetCDF files: one file contains the statistics of the burst data and the other file contains the raw burst data (additional details described below). One important advantage of this toolbox is that it converts the data into NetCDF format. Data in NetCDF format is easy to disseminate, is portable to any computer platform, and is viewable with public-domain freely-available software. Another important advantage is that a metadata

  18. RADIATION WAVE DETECTION

    DOEpatents

    Wouters, L.F.

    1960-08-30

    Radiation waves can be detected by simultaneously measuring radiation- wave intensities at a plurality of space-distributed points and producing therefrom a plot of the wave intensity as a function of time. To this end. a detector system is provided which includes a plurality of nuclear radiation intensity detectors spaced at equal radial increments of distance from a source of nuclear radiation. Means are provided to simultaneously sensitize the detectors at the instant a wave of radiation traverses their positions. the detectors producing electrical pulses indicative of wave intensity. The system further includes means for delaying the pulses from the detectors by amounts proportional to the distance of the detectors from the source to provide an indication of radiation-wave intensity as a function of time.

  19. A pitfall in shallow shear-wave refraction surveying

    USGS Publications Warehouse

    Xia, J.; Miller, R.D.; Park, C.B.; Wightman, E.; Nigbor, R.

    2002-01-01

    The shallow shear-wave refraction method works successfully in an area with a series of horizontal layers. However, complex near-surface geology may not fit into the assumption of a series of horizontal layers. That a plane SH-wave undergoes wave-type conversion along an interface in an area of nonhorizontal layers is theoretically inevitable. One real example shows that the shallow shear-wave refraction method provides velocities of a converted wave rather than an SH- wave. Moreover, it is impossible to identify the converted wave by refraction data itself. As most geophysical engineering firms have limited resources, an additional P-wave refraction survey is necessary to verify if velocities calculated from a shear-wave refraction survey are velocities of converted waves. The alternative at this time may be the surface wave method, which can provide reliable S-wave velocities, even in an area of velocity inversion (a higher velocity layer underlain by a lower velocity layer). ?? 2002 Elsevier Science B.V. All rights reserved.

  20. Modulation of chorus intensity by ULF waves deep in the inner magnetosphere

    NASA Astrophysics Data System (ADS)

    Xia, Zhiyang; Chen, Lunjin; Dai, Lei; Claudepierre, Seth G.; Chan, Anthony A.; Soto-Chavez, A. R.; Reeves, G. D.

    2016-09-01

    Previous studies have shown that chorus wave intensity can be modulated by Pc4-Pc5 compressional ULF waves. In this study, we present Van Allen Probes observation of ULF wave modulating chorus wave intensity, which occurred deep in the magnetosphere. The ULF wave shows fundamental poloidal mode signature and mirror mode compressional nature. The observed ULF wave can modulate not only the chorus wave intensity but also the distribution of both protons and electrons. Linear growth rate analysis shows consistence with observed chorus intensity variation at low frequency (f <˜ 0.3fce), but cannot account for the observed higher-frequency chorus waves, including the upper band chorus waves. This suggests the chorus waves at higher-frequency ranges require nonlinear mechanisms. In addition, we use combined observations of Radiation Belt Storm Probes (RBSP) A and B to verify that the ULF wave event is spatially local and does not last long.

  1. Kinesthetic Transverse Wave Demonstration

    NASA Astrophysics Data System (ADS)

    Pantidos, Panagiotis; Patapis, Stamatis

    2005-09-01

    This is a variation on the String and Sticky Tape demonstration "The Wave Game," suggested by Ron Edge. A group of students stand side by side, each one holding a card chest high with both hands. The teacher cues the first student to begin raising and lowering his card. When he starts lowering his card, the next student begins to raise his. As succeeding students move their cards up and down, a wave such as that shown in the figure is produced. To facilitate the process, students' motions were synchronized with the ticks of a metronome (without such synchronization it was nearly impossible to generate a satisfactory wave). Our waves typically had a frequency of about 1 Hz and a wavelength of around 3 m. We videotaped the activity so that the students could analyze the motions. The (17-year-old) students had not received any prior instruction regarding wave motion and did not know beforehand the nature of the exercise they were about to carry out. During the activity they were asked what a transverse wave is. Most of them quickly realized, without teacher input, that while the wave propagated horizontally, the only motion of the transmitting medium (them) was vertical. They located the equilibrium points of the oscillations, the crests and troughs of the waves, and identified the wavelength. The teacher defined for them the period of the oscillations of the motion of a card to be the total time for one cycle. The students measured this time and then several asserted that it was the same as the wave period. Knowing the length of the waves and the number of waves per second, the next step can easily be to find the wave speed.

  2. Internal Waves, Indian Ocean

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This photograph, taken in sunglint conditions, captures open ocean internal waves which are diffracting around shoals south of the Seychelle islands (4.5S, 55.5E) and recombining to form interference patterns. The clouds to the north of the waves cover two of the Seychelle islands: Silhouette and Mahe. Mahe is the main island of the archipelago. The small rocky island surrounded by reef around which the waves diffract is Platte Island.

  3. Hydrodynamic waves in an anomalous charged fluid

    NASA Astrophysics Data System (ADS)

    Abbasi, Navid; Davody, Ali; Hejazi, Kasra; Rezaei, Zahra

    2016-11-01

    We study the collective excitations in a relativistic fluid with an anomalous U (1) current. In 3 + 1 dimensions at zero chemical potential, in addition to ordinary sound modes we find two propagating modes in presence of an external magnetic field. The first one which is a transverse degenerate mode, propagates with a velocity proportional to the coefficient of gravitational anomaly; this is in fact the Chiral Alfvén wave recently found in [1]. Another one is a wave of density perturbation, namely a chiral magnetic wave (CMW). The velocity dependence of CMW on the chiral anomaly coefficient is well known. We compute the dependence of CMW's velocity on the coefficient of gravitational anomaly as well. We also show that the dissipation splits the degeneracy of CAW. At finite chiral charge density we show that in general there may exist five chiral hydrodynamic waves. Of these five waves, one is the CMW while the other four are mixed Modified Sound-Alfvén waves. It turns out that in propagation transverse to the magnetic field no anomaly effect appears while in parallel to the magnetic field we find sound waves become dispersive due to anomaly.

  4. Nonlinear noise waves in soft biological tissues

    NASA Astrophysics Data System (ADS)

    Rudenko, O. V.; Gurbatov, S. N.; Demin, I. Yu.

    2013-09-01

    The study of intense waves in soft biological tissues is necessary both for diagnostics and therapeutic aims. Tissue represents an inherited medium with frequency-dependent dissipative properties, in which waves are described by nonlinear integro-differential equations. The equations for such waves are well known. Their group analysis has been performed, and a number of exact solutions have been found. However, statistical problems for nonlinear waves in tissues have hardly been studied. As well, for medical applications, both intense noise waves and waves with fluctuating parameters can be used. In addition, statistical solutions are simpler in structure than regular solutions; they are useful for understanding the physics of processes. Below a general approach is described for solving nonlinear statistical problems applied to the considered mathematical models of biological tissues. We have calculated the dependences of the intensities of the narrowband noise harmonics on distance. For wideband noise, we have calculated the dependence of the spectral integral intensity on distance. In all cases, wave attenuation is determined both by the specific dissipative properties of the tissue and the nonlinearity of the medium.

  5. Millimeter wave dosimetry of human skin.

    PubMed

    Alekseev, S I; Radzievsky, A A; Logani, M K; Ziskin, M C

    2008-01-01

    To identify the mechanisms of biological effects of mm waves it is important to develop accurate methods for evaluating absorption and penetration depth of mm waves in the epidermis and dermis. The main characteristics of mm wave skin dosimetry were calculated using a homogeneous unilayer model and two multilayer models of skin. These characteristics included reflection, power density (PD), penetration depth (delta), and specific absorption rate (SAR). The parameters of the models were found from fitting the models to the experimental data obtained from measurements of mm wave reflection from human skin. The forearm and palm data were used to model the skin with thin and thick stratum corneum (SC), respectively. The thin SC produced little influence on the interaction of mm waves with skin. On the contrary, the thick SC in the palm played the role of a matching layer and significantly reduced reflection. In addition, the palmar skin manifested a broad peak in reflection within the 83-277 GHz range. The viable epidermis plus dermis, containing a large amount of free water, greatly attenuated mm wave energy. Therefore, the deeper fat layer had little effect on the PD and SAR profiles. We observed the appearance of a moderate SAR peak in the therapeutic frequency range (42-62 GHz) within the skin at a depth of 0.3-0.4 mm. Millimeter waves penetrate into the human skin deep enough (delta = 0.65 mm at 42 GHz) to affect most skin structures located in the epidermis and dermis.

  6. Nonlinear waves and coherent structures in the quantum single-wave model

    SciTech Connect

    Tzenov, Stephan I.; Marinov, Kiril B.

    2011-10-15

    Starting from the von Neumann-Maxwell equations for the Wigner quasi-probability distribution and for the self-consistent electric field, the quantum analog of the classical single-wave model has been derived. The linear stability of the quantum single-wave model has been studied, and periodic in time patterns have been found both analytically and numerically. In addition, some features of quantum chaos have been detected in the unstable region in parameter space. Further, a class of standing-wave solutions of the quantum single-wave model has also been found, which have been observed to behave as stable solitary-wave structures. The analytical results have been finally compared to the exact system dynamics obtained by solving the corresponding equations in Schrodinger representation numerically.

  7. Dispersion of waves in porous cylinders with patchy saturation Part I. Formulaton and torsional waves

    SciTech Connect

    Berryman, J G; Pride, S R

    2004-07-28

    Laboratory experiments on wave propagation through saturated and partially saturated porous media have often been conducted on porous cylinders that were initially fully saturated and then allowed to dry while continuing to acquire data on the wave behavior. Since it is known that drying typically progresses from outside to inside, a sensible physical model of this process is concentric cylinders having different saturation levels--the simplest example being a fully dry outer cylindrical shell together with a fully wet inner cylinder. We use this model to formulate the equations for wave dispersion in porous cylinders for patchy saturation (i.e. drainage) conditions. In addition to multiple modes of propagation obtained numerically from these dispersion relations, we find two distinct analytical expressions for torsional wave modes. We solve the dispersion relation for torsional waves for two examples: Massillon sandstone and Sierra White granite. The drainage analysis appears to give improved agreement with the data for both these materials.

  8. Optical rogue waves.

    PubMed

    Solli, D R; Ropers, C; Koonath, P; Jalali, B

    2007-12-13

    Recent observations show that the probability of encountering an extremely large rogue wave in the open ocean is much larger than expected from ordinary wave-amplitude statistics. Although considerable effort has been directed towards understanding the physics behind these mysterious and potentially destructive events, the complete picture remains uncertain. Furthermore, rogue waves have not yet been observed in other physical systems. Here, we introduce the concept of optical rogue waves, a counterpart of the infamous rare water waves. Using a new real-time detection technique, we study a system that exposes extremely steep, large waves as rare outcomes from an almost identically prepared initial population of waves. Specifically, we report the observation of rogue waves in an optical system, based on a microstructured optical fibre, near the threshold of soliton-fission supercontinuum generation--a noise-sensitive nonlinear process in which extremely broadband radiation is generated from a narrowband input. We model the generation of these rogue waves using the generalized nonlinear Schrödinger equation and demonstrate that they arise infrequently from initially smooth pulses owing to power transfer seeded by a small noise perturbation.

  9. Thermal-Wave Microscope

    NASA Technical Reports Server (NTRS)

    Jones, Robert E.; Kramarchuk, Ihor; Williams, Wallace D.; Pouch, John J.; Gilbert, Percy

    1989-01-01

    Computer-controlled thermal-wave microscope developed to investigate III-V compound semiconductor devices and materials. Is nondestructive technique providing information on subsurface thermal features of solid samples. Furthermore, because this is subsurface technique, three-dimensional imaging also possible. Microscope uses intensity-modulated electron beam of modified scanning electron microscope to generate thermal waves in sample. Acoustic waves generated by thermal waves received by transducer and processed in computer to form images displayed on video display of microscope or recorded on magnetic disk.

  10. Incorporating social concerns in environmental impact assessments

    SciTech Connect

    Wolfe, A.K.

    1990-03-01

    Social impact assessments most often focus on the population-driven impacts of projects. Such impacts may be insignificant when compared with social structural impacts of complex, controversial projects. This set of impacts includes social disruption, social group formation, and stigma effects. The National Environmental Policy Act does not explicitly call for assessment of, and assessors often are reluctant to address, these complex issues. This paper discusses why such impacts are critical to assess and gives examples of how they have been incorporated into environmental assessment documents. 6 refs.

  11. Valve system incorporating single failure protection logic

    DOEpatents

    Ryan, Rodger; Timmerman, Walter J. H.

    1980-01-01

    A valve system incorporating single failure protective logic. The system consists of a valve combination or composite valve which allows actuation or de-actuation of a device such as a hydraulic cylinder or other mechanism, integral with or separate from the valve assembly, by means of three independent input signals combined in a function commonly known as two-out-of-three logic. Using the input signals as independent and redundant actuation/de-actuation signals, a single signal failure, or failure of the corresponding valve or valve set, will neither prevent the desired action, nor cause the undesired action of the mechanism.

  12. Radiation collimator and systems incorporating same

    DOEpatents

    Norman, Daren R.; Yoon, Woo Y.; Jones, James L.; Haskell, Kevin J.; Bennett, Brion D.; Tschaggeny, Charles W.; Jones, Warren F.

    2011-09-13

    A collimator including a housing having disposed therein a shield element surrounding a converter core in which a photon beam is generated from electrons emanating from a linear accelerator. A beam channeler longitudinally adjacent the shield element has a beam aperture therethrough coaxially aligned with, and of the same diameter as, an exit bore of the converter core. A larger entry bore in the converter core is coaxial with, and longitudinally separated from, the exit bore thereof. Systems incorporating the collimator are also disclosed.

  13. Carbazole incorporated ratiometric chemosensor for Zn2+

    NASA Astrophysics Data System (ADS)

    Helal, Aasif; Kim, Hong-Seok

    2013-03-01

    An electron donating carbazole incorporated thiazole (3) based Zn2+ selective intrinsic chemosensor has been synthesized and investigated. It was found that electron donating substituents such as methyl and carbazole on chemosensor (1) produce remarkable red shift in emission upon complexation with Zn2+. The sensor shows a selective fluorescence response with Zn2+ over biologically relevant cations (Ca2+, Mg2+, Na+, and K+) and biologically non-relevant cations (Cd2+, In3+ and Ga3+) in an aqueous ethanol system. It also produce an enhancement in the quantum yield and a longer emission wavelength shift on Zn2+ binding with the potential of a ratiometric assay.

  14. Incorporation of noble metals into aerogels

    DOEpatents

    Hair, Lucy M.; Sanner, Robert D.; Coronado, Paul R.

    1998-01-01

    Aerogels or xerogels containing atomically dispersed noble metals for applications such environmental remediation. New noble metal precursors, such as Pt--Si or Pd(Si--P).sub.2, have been created to bridge the incompatibility between noble metals and oxygen, followed by their incorporation into the aerogel or xerogel through sol-gel chemistry and processing. Applications include oxidation of hydrocarbons and reduction of nitrogen oxide species, complete oxidation of volatile organic carbon species, oxidative membranes for photocatalysis and partial oxidation for synthetic applications.

  15. Incorporating opponent models into adversary search

    SciTech Connect

    Carmel, D.; Markovitch, S.

    1996-12-31

    This work presents a generalized theoretical framework that allows incorporation of opponent models into adversary search. We present the M* algorithm, a generalization of minimax that uses an arbitrary opponent model to simulate the opponent`s search. The opponent model is a recursive structure consisting of the opponent`s evaluation function and its model of the player. We demonstrate experimentally the potential benefit of using an opponent model. Pruning in M* is impossible in the general case. We prove a sufficient condition for pruning and present the {alpha}{beta}* algorithm which returns the M* value of a tree while searching only necessary branches.

  16. Incorporation of radioactive wastes into styrenated polyester

    SciTech Connect

    Ikladious, N.E.; Ghattas, N.K.; Eskander, S.B.

    1986-01-01

    Styrenated polyester (poly(oxydiethylene maleate)) is examined as a medium for immobilization of simulated spent-ion exchange resin used at Inshas Reactor (Egypt). Compressive strength and hardness values illustrated the stability of the final products towards radiation. TG, DTG, and DTA diagrams showed the thermal instability of the final waste form at about 375/sup 0/C. Leaching experiment on incorporated blocks of active resin labelled with /sup 137/Cs, /sup 144/Ce, and /sup 106/Ru showed that the cumulative leaching rate for Ce is lower than those for Ru and Cs.

  17. Incorporation of Nanosensors into Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J.

    2007-01-01

    Traditional sensors are too big and heavy for installation in space vehicles, including the Space Shuttle Orbiter as well as future manned and unmanned vehicles currently in the early design phase. Advances in nanotechnology have led to the availability of smaller and more accurate sensors. Multiple and redundant nanosensors can be used to conduct more accurate and comprehensive measurements in a space vehicle. Early planning can lead to the relatively easy incorporation of miniature sensors sharing power and communication lines, thus reducing the requirement for large amount of electrical and/or optical cabling.

  18. Incorporation of noble metals into aerogels

    DOEpatents

    Hair, L.M.; Sanner, R.D.; Coronado, P.R.

    1998-12-22

    Aerogels or xerogels containing atomically dispersed noble metals for applications such as environmental remediation are disclosed. New noble metal precursors, such as Pt--Si or Pd(Si--P){sub 2}, have been created to bridge the incompatibility between noble metals and oxygen, followed by their incorporation into the aerogel or xerogel through sol-gel chemistry and processing. Applications include oxidation of hydrocarbons and reduction of nitrogen oxide species, complete oxidation of volatile organic carbon species, oxidative membranes for photocatalysis and partial oxidation for synthetic applications.

  19. Incorporation of aluminum nanopowder into NTO.

    SciTech Connect

    Lee, K. Y.; Kennedy, J. E.; Peterson, P. D.; Asay, B. W.

    2004-01-01

    Most insensitive high explosives have relatively low output and the user is forced to choose between enhancing operational safety and meeting ordnance performance requirements. The goals of this project are to investigate ways to incorporate Al nanopowder in NTO and to devise formulations that are insensitive and that exhibit high performance. In this paper, the novel method for the preparation of nanoNTO and its formulation with Al nanopowder will be presented, together with the characterization test results. Data from minisandwich velocity test on NTO and NTO/Al mix and the techniques used to verify the potential encapsulation of Al in NTO will also be presented.

  20. Staphylococcus aureus Sortase A-Mediated Incorporation of Peptides: Effect of Peptide Modification on Incorporation

    PubMed Central

    Hansenová Maňásková, Silvie; Nazmi, Kamran; van ‘t Hof, Wim; van Belkum, Alex; Martin, Nathaniel I.; Bikker, Floris J.; van Wamel, Willem J. B.; Veerman, Enno C. I.

    2016-01-01

    The endogenous Staphylococcus aureus sortase A (SrtA) transpeptidase covalently anchors cell wall-anchored (CWA) proteins equipped with a specific recognition motif (LPXTG) into the peptidoglycan layer of the staphylococcal cell wall. Previous in situ experiments have shown that SrtA is also able to incorporate exogenous, fluorescently labelled, synthetic substrates equipped with the LPXTG motif (K(FITC)LPETG-amide) into the bacterial cell wall, albeit at high concentrations of 500 μM to 1 mM. In the present study, we have evaluated the effect of substrate modification on the incorporation efficiency. This revealed that (i) by elongation of LPETG-amide with a sequence of positively charged amino acids, derived from the C-terminal domain of physiological SrtA substrates, the incorporation efficiency was increased by 20-fold at 10 μM, 100 μM and 250 μM; (ii) Substituting aspartic acid (E) for methionine increased the incorporation of the resulting K(FITC)LPMTG-amide approximately three times at all concentrations tested; (iii) conjugation of the lipid II binding antibiotic vancomycin to K(FITC)LPMTG-amide resulted in the same incorporation levels as K(FITC)LPETG-amide, but much more efficient at an impressive 500-fold lower substrate concentration. These newly developed synthetic substrates can potentially find broad applications in for example the in situ imaging of bacteria; the incorporation of antibody recruiting moieties; the targeted delivery and covalent incorporation of antimicrobial compounds into the bacterial cell wall. PMID:26799839

  1. Wave-climate assessment by satellite remote sensing

    SciTech Connect

    Barstow, S.; Krogstad, H.E.

    1995-10-01

    Satellite remote sensing based on radar altimetry and the synthetic aperture radar (SAR) can be used for accurate ocean-wave climatology globally. The altimeter provides significant wave height and wind speed whereas SAR in principle gives the full wave spectrum. Over the next few years, altimeter-derived wave heights will become the basic data sources for open-ocean statistics and SAR, in combination with results from global wave models, will provide the corresponding directional statistics. In addition, SAR may be used for studying wave conditions in near coastal areas. In the Norwegian Sea and elsewhere, real-time SAT and altimeter data are now being used operationally for forecasting and assimilation into numerical wave models.

  2. Generalized theory of helicon waves. I. Normal modes

    SciTech Connect

    Chen, F.F.; Arnush, D.

    1997-09-01

    The theory of helicon waves is extended to include finite electron mass. This introduces an additional branch to the dispersion relation that is essentially an electron cyclotron or Trivelpiece{endash}Gould (TG) wave with a short radial wavelength. The effect of the TG wave is expected to be important only for low dc magnetic fields and long parallel wavelengths. The normal modes at low fields are mixtures of the TG wave and the usual helicon wave and depend on the nature of the boundaries. Computations show, however, that since the TG waves are damped near the surface of the plasma, the helicon wave at high fields is almost exactly the same as is found when the electron mass is neglected. {copyright} {ital 1997 American Institute of Physics.}

  3. Lamb Wave Assessment of Fiber Volume Fraction in Composites

    NASA Technical Reports Server (NTRS)

    Seale, Michael D.; Smith, Barry T.; Prosser, W. H.; Zalameda, Joseph N.

    1998-01-01

    Among the various techniques available, ultrasonic Lamb waves offer a convenient method of examining composite materials. Since the Lamb wave velocity depends on the elastic properties of a material, an effective tool exists to evaluate composites by measuring the velocity of these waves. Lamb waves can propagate over long distances and are sensitive to the desired in-plane elastic properties of the material. This paper discusses a study in which Lamb waves were used to examine fiber volume fraction variations of approximately 0.40-0.70 in composites. The Lamb wave measurements were compared to fiber volume fractions obtained from acid digestion tests. Additionally, a model to predict the fiber volume fraction from Lamb wave velocity values was evaluated.

  4. Localization of Waves in Merged Lattices.

    PubMed

    Alagappan, G; Png, C E

    2016-01-01

    This article describes a new two-dimensional physical topology-merged lattice, that allows dense number of wave localization states. Merged lattices are obtained as a result of merging two lattices of scatters of the same space group, but with slightly different spatial resonances. Such merging creates two-dimensional scattering "beats" which are perfectly periodic on the longer spatial scale. On the shorter spatial scale, the systematic breakage of the translational symmetry leads to strong wave scattering, and this causes the occurrences of wave localization states. Merged Lattices promises variety of localization states including tightly confined, and ring type annular modes. The longer scale perfect periodicity of the merged lattice, enables complete prediction and full control over the density of the localization states and its' quality factors. In addition, the longer scale periodicity, also allows design of integrated slow wave components. Merged lattices, thus, can be engineered easily to create technologically beneficial applications. PMID:27535096

  5. Comment on ``Atomic gravitational wave interferometric sensor''

    NASA Astrophysics Data System (ADS)

    Bender, Peter L.

    2011-07-01

    The use of laser interferometers for detecting and studying gravitational-wave signals from many types of astronomical sources is being pursued actively by a number of groups in different countries. However, it has been suggested recently that cooled atom clouds in atom interferometers could be used to replace the test masses in space-based gravitational-wave detectors and the end mirrors in ground-based detectors [S. Dimopoulos, P. W. Graham, J. M. Hogan, M. A. Kasevich, and S. Rajendran, Phys. Rev. DPRVDAQ1550-7998 78, 122002 (2008).10.1103/PhysRevD.78.122002]. Some new error sources that apparently have not been included in proposals of atom interferometer gravitational-wave detectors will be discussed in this comment. They are based on additional effects of aberrations in the laser wave fronts that interact with the atom clouds.

  6. Localization of Waves in Merged Lattices

    PubMed Central

    Alagappan, G.; Png, C. E.

    2016-01-01

    This article describes a new two–dimensional physical topology–merged lattice, that allows dense number of wave localization states. Merged lattices are obtained as a result of merging two lattices of scatters of the same space group, but with slightly different spatial resonances. Such merging creates two–dimensional scattering “beats” which are perfectly periodic on the longer spatial scale. On the shorter spatial scale, the systematic breakage of the translational symmetry leads to strong wave scattering, and this causes the occurrences of wave localization states. Merged Lattices promises variety of localization states including tightly confined, and ring type annular modes. The longer scale perfect periodicity of the merged lattice, enables complete prediction and full control over the density of the localization states and its’ quality factors. In addition, the longer scale periodicity, also allows design of integrated slow wave components. Merged lattices, thus, can be engineered easily to create technologically beneficial applications. PMID:27535096

  7. Steepening of waves at the duskside magnetopause

    NASA Astrophysics Data System (ADS)

    Plaschke, F.; Kahr, N.; Fischer, D.; Nakamura, R.; Baumjohann, W.; Magnes, W.; Burch, J. L.; Torbert, R. B.; Russell, C. T.; Giles, B. L.; Strangeway, R. J.; Leinweber, H. K.; Bromund, K. R.; Anderson, B. J.; Le, G.; Chutter, M.; Slavin, J. A.; Kepko, E. L.

    2016-07-01

    Surface waves at the magnetopause flanks typically feature steeper, i.e., more inclined leading (antisunward facing) than trailing (sunward facing) edges. This is expected for Kelvin-Helmholtz instability (KHI) amplified waves. Very rarely, during northward interplanetary magnetic field (IMF) conditions, anomalous/inverse steepening has been observed. The small-scale tetrahedral configuration of the Magnetospheric Multiscale spacecraft and their high time resolution measurements enable us to routinely ascertain magnetopause boundary inclinations during surface wave passage with high accuracy by four-spacecraft timing analysis. At the dusk flank magnetopause, 77%/23% of the analyzed wave intervals exhibit regular/inverse steepening. Inverse steepening happens during northward IMF conditions, as previously reported and, in addition, during intervals of dominant equatorial IMF. Inverse steepening observed under the latter conditions may be due to the absence of KHI or due to instabilities arising from the alignment of flow and magnetic fields in the magnetosheath.

  8. Localization of Waves in Merged Lattices

    NASA Astrophysics Data System (ADS)

    Alagappan, G.; Png, C. E.

    2016-08-01

    This article describes a new two-dimensional physical topology-merged lattice, that allows dense number of wave localization states. Merged lattices are obtained as a result of merging two lattices of scatters of the same space group, but with slightly different spatial resonances. Such merging creates two-dimensional scattering “beats” which are perfectly periodic on the longer spatial scale. On the shorter spatial scale, the systematic breakage of the translational symmetry leads to strong wave scattering, and this causes the occurrences of wave localization states. Merged Lattices promises variety of localization states including tightly confined, and ring type annular modes. The longer scale perfect periodicity of the merged lattice, enables complete prediction and full control over the density of the localization states and its’ quality factors. In addition, the longer scale periodicity, also allows design of integrated slow wave components. Merged lattices, thus, can be engineered easily to create technologically beneficial applications.

  9. Gravitational waves in fourth order gravity

    NASA Astrophysics Data System (ADS)

    Capozziello, S.; Stabile, A.

    2015-08-01

    In the post-Minkowskian limit approximation, we study gravitational wave solutions for general fourth-order theories of gravity. Specifically, we consider a Lagrangian with a generic function of curvature invariants . It is well known that when dealing with General Relativity such an approach provides massless spin-two waves as propagating degree of freedom of the gravitational field while this theory implies other additional propagating modes in the gravity spectra. We show that, in general, fourth order gravity, besides the standard massless graviton is characterized by two further massive modes with a finite-distance interaction. We find out the most general gravitational wave solutions in terms of Green functions in vacuum and in presence of matter sources. If an electromagnetic source is chosen, only the modes induced by are present, otherwise, for any gravity model, we have the complete analogy with tensor modes of General Relativity. Polarizations and helicity states are classified in the hypothesis of plane wave.

  10. Localization of Waves in Merged Lattices.

    PubMed

    Alagappan, G; Png, C E

    2016-08-18

    This article describes a new two-dimensional physical topology-merged lattice, that allows dense number of wave localization states. Merged lattices are obtained as a result of merging two lattices of scatters of the same space group, but with slightly different spatial resonances. Such merging creates two-dimensional scattering "beats" which are perfectly periodic on the longer spatial scale. On the shorter spatial scale, the systematic breakage of the translational symmetry leads to strong wave scattering, and this causes the occurrences of wave localization states. Merged Lattices promises variety of localization states including tightly confined, and ring type annular modes. The longer scale perfect periodicity of the merged lattice, enables complete prediction and full control over the density of the localization states and its' quality factors. In addition, the longer scale periodicity, also allows design of integrated slow wave components. Merged lattices, thus, can be engineered easily to create technologically beneficial applications.

  11. Accurate and efficient modeling of global seismic wave propagation for an attenuative Earth model including the center

    NASA Astrophysics Data System (ADS)

    Toyokuni, Genti; Takenaka, Hiroshi

    2012-06-01

    We propose a method for modeling global seismic wave propagation through an attenuative Earth model including the center. This method enables accurate and efficient computations since it is based on the 2.5-D approach, which solves wave equations only on a 2-D cross section of the whole Earth and can correctly model 3-D geometrical spreading. We extend a numerical scheme for the elastic waves in spherical coordinates using the finite-difference method (FDM), to solve the viscoelastodynamic equation. For computation of realistic seismic wave propagation, incorporation of anelastic attenuation is crucial. Since the nature of Earth material is both elastic solid and viscous fluid, we should solve stress-strain relations of viscoelastic material, including attenuative structures. These relations represent the stress as a convolution integral in time, which has had difficulty treating viscoelasticity in time-domain computation such as the FDM. However, we now have a method using so-called memory variables, invented in the 1980s, followed by improvements in Cartesian coordinates. Arbitrary values of the quality factor (Q) can be incorporated into the wave equation via an array of Zener bodies. We also introduce the multi-domain, an FD grid of several layers with different grid spacings, into our FDM scheme. This allows wider lateral grid spacings with depth, so as not to perturb the FD stability criterion around the Earth center. In addition, we propose a technique to avoid the singularity problem of the wave equation in spherical coordinates at the Earth center. We develop a scheme to calculate wavefield variables on this point, based on linear interpolation for the velocity-stress, staggered-grid FDM. This scheme is validated through a comparison of synthetic seismograms with those obtained by the Direct Solution Method for a spherically symmetric Earth model, showing excellent accuracy for our FDM scheme. As a numerical example, we apply the method to simulate seismic

  12. Toxicity and immunogenicity of Neisseria meningitidis lipopolysaccharide incorporated into liposomes.

    PubMed

    Petrov, A B; Semenov, B F; Vartanyan, Y P; Zakirov, M M; Torchilin, V P; Trubetskoy, V S; Koshkina, N V; L'Vov, V L; Verner, I K; Lopyrev, I V

    1992-09-01

    To obtain nontoxic and highly immunogenic lipopolysaccharide (LPS) for immunization, we incorporated Neisseria meningitidis LPS into liposomes. Native LPS and its salts were incorporated by the method of dehydration-rehydration of vesicles or prolonged cosonication. The most complete incorporation of LPS into liposomes and a decrease in toxicity were achieved by the method of dehydration-rehydration of vesicles. Three forms of LPS (H+ form, Mg2+ salt, and triethanolamine salt) showed different solubilities in water, the acidic form of LPS, with the most pronounced hydrophobic properties, being capable of practically complete association with liposomal membranes. An evaluation of the activity of liposomal LPS in vitro (by the Limulus amoebocyte test) and in vivo (by monitoring the pyrogenic reaction in rabbits) revealed a decrease in endotoxin activity of up to 1,000-fold. In addition, the pyrogenic activity of liposomal LPS was comparable to that of a meningococcal polysaccharide vaccine. Liposomes had a pronounced adjuvant effect on the immune response to LPS. Thus, the level of anti-LPS plaque-forming cells in the spleens of mice immunized with liposomal LPS was 1 order of magnitude higher and could be observed for a longer time (until day 21, i.e., the term of observation) than in mice immunized with free LPS. The same regularity was revealed in a study done with an enzyme-linked immunosorbent assay. This study also established that antibodies induced by immunization belonged to the immunoglobulin M and G classes, which are capable of prolonged circulation. Moreover, liposomal LPS induced a pronounced immune response in CBA/N mice (defective in B lymphocytes of the LyB-5+ subpopulation). The latter results indicate that the immunogenic action of liposomal LPS occurs at an early age.

  13. Toxicity and immunogenicity of Neisseria meningitidis lipopolysaccharide incorporated into liposomes.

    PubMed Central

    Petrov, A B; Semenov, B F; Vartanyan, Y P; Zakirov, M M; Torchilin, V P; Trubetskoy, V S; Koshkina, N V; L'Vov, V L; Verner, I K; Lopyrev, I V

    1992-01-01

    To obtain nontoxic and highly immunogenic lipopolysaccharide (LPS) for immunization, we incorporated Neisseria meningitidis LPS into liposomes. Native LPS and its salts were incorporated by the method of dehydration-rehydration of vesicles or prolonged cosonication. The most complete incorporation of LPS into liposomes and a decrease in toxicity were achieved by the method of dehydration-rehydration of vesicles. Three forms of LPS (H+ form, Mg2+ salt, and triethanolamine salt) showed different solubilities in water, the acidic form of LPS, with the most pronounced hydrophobic properties, being capable of practically complete association with liposomal membranes. An evaluation of the activity of liposomal LPS in vitro (by the Limulus amoebocyte test) and in vivo (by monitoring the pyrogenic reaction in rabbits) revealed a decrease in endotoxin activity of up to 1,000-fold. In addition, the pyrogenic activity of liposomal LPS was comparable to that of a meningococcal polysaccharide vaccine. Liposomes had a pronounced adjuvant effect on the immune response to LPS. Thus, the level of anti-LPS plaque-forming cells in the spleens of mice immunized with liposomal LPS was 1 order of magnitude higher and could be observed for a longer time (until day 21, i.e., the term of observation) than in mice immunized with free LPS. The same regularity was revealed in a study done with an enzyme-linked immunosorbent assay. This study also established that antibodies induced by immunization belonged to the immunoglobulin M and G classes, which are capable of prolonged circulation. Moreover, liposomal LPS induced a pronounced immune response in CBA/N mice (defective in B lymphocytes of the LyB-5+ subpopulation). The latter results indicate that the immunogenic action of liposomal LPS occurs at an early age. PMID:1500196

  14. The next wave: confexting.

    PubMed

    Lm, Shah; Ep, Quigley; Rh, Wiggins

    2012-02-01

    Radiology conferences enable participants the opportunity to ask experts questions through question and answer (Q and A) sessions or individually. Given the time limitations and intimidating circumstances, we incorporated conference text messaging (confexting) as a method of increasing interactivity between the audience and speakers. During a 5-day radiology conference, text messaging was utilized for anonymous interactivity between the audience and speakers during Q and A sessions. There were 324 text messages; 76 of these were either follow-up statements or questions related to earlier text messages. Forty-two questions were submitted via paper notes. There was a general trend of an increasing number of text messages and a decreasing number of paper notes. The anonymous text messaging system was found to be an effective method for interactivity between the audience and the speakers. The questions and answers could be presented in a PowerPoint format at the formal Q and A sessions. Questions texted to the authors during their talks could be immediately answered or addressed in subsequent talks. Although difficult for some individuals to embrace technology, confexting allows for interactivity and prompts discussion. Confexting is an effective method for interactivity between the audience and speakers not previously utilized in a conference setting. The anonymity and asynchronous communication enable conference participants to submit more questions than in the traditional setting. The speakers may be able to explain more thoroughly difficult concepts more thoroughly with additional slides at Q and A sessions or may immediately answer texted questions during their talks. PMID:21748414

  15. Incorporation of l-[14C]leucine into egg proteins by liver slices from cod

    PubMed Central

    Plack, P. A.; Fraser, N. W.

    1971-01-01

    1. Liver slices from cod (Gadus morhua L.) were incubated with l-[14C]leucine and the incorporation of label into total protein, precipitated with trichloroacetic acid, and into egg proteins, precipitated with an antibody after addition of carrier egg proteins, was measured. 2. Liver slices from immature male or female cod, and from male fish with developing testes, did not incorporate significant amounts of l-[14C]leucine into egg proteins, whereas with slices from female cod with developing ovaries the rate of incorporation into egg proteins was 8% of the rate of incorporation into total protein. 3. Liver slices from immature male or female fish that had received an intramuscular injection of oestradiol benzoate (1mg/kg) 5–8 days previously incorporated l-[14C]leucine into egg proteins at about 26% of the rate of incorporation into total protein. 4. Incorporation into total protein and into egg proteins was inhibited by puromycin, and 1.2 and 0.13μg of puromycin/mg of tissue protein, respectively, gave 50% inhibition. PMID:16742749

  16. Cell-free unnatural amino acid incorporation with alternative energy systems and linear expression templates.

    PubMed

    Shrestha, Prashanta; Smith, Mark Thomas; Bundy, Bradley Charles

    2014-01-25

    Site-specific incorporation of unnatural amino acids (uAAs) during protein synthesis expands the proteomic code through the addition of unique residue chemistry. This field provides a unique tool to improve pharmacokinetics, cancer treatments, vaccine development, proteomics and protein engineering. The limited ability to predict the characteristics of proteins with uAA-incorporation creates a need for a low-cost system with the potential for rapid screening. Escherichia coli-based cell-free protein synthesis is a compelling platform for uAA incorporation due to the open and accessible nature of the reaction environment. However, typical cell-free systems can be expensive due to the high cost of energizing reagents. By employing alternative energy sources, we reduce the cost of uAA-incorporation in CFPS by 55%. While alternative energy systems reduce cost, the time investment to develop gene libraries can remain cumbersome. Cell-free systems allow the direct use of PCR products known as linear expression templates, thus alleviating tedious plasmid library preparations steps. We report the specific costs of CFPS with uAA incorporation, demonstrate that LETs are suitable expression templates with uAA-incorporation, and consider the substantial reduction in labor intensity using LET-based expression for CFPS uAA incorporation.

  17. Transient Wave Envelope Elements for Wave Problems

    NASA Astrophysics Data System (ADS)

    Astley, R. J.

    1996-04-01

    A novel family of infinite wave envelope elements is described which can be used in conjunction with conventional finite elements to model the transient wave equation in unbounded regions. The elements are obtained by applying an inverse Fourier transformation to a mapped wave envelope formulation in the frequency domain. The discrete transient equations obtained in this way can be applied to two-dimensional and three-dimensional problems without restriction, being valid over a full range of excitation frequencies. The effectiveness and accuracy of the method is demonstrated in application to simple test cases which involve the calculation of transient sound fields generated by pulsating spheres and cylinders excited from rest in an unbounded region. Test solutions are compared to analytic solutions and to finite element solutions obtained by using large computational grids which extend beyond the region influenced by the transient disturbance.

  18. Full-wave and half-wave rectification in second-order motion perception

    NASA Technical Reports Server (NTRS)

    Solomon, J. A.; Sperling, G.

    1994-01-01

    Microbalanced stimuli are dynamic displays which do not stimulate motion mechanisms that apply standard (Fourier-energy or autocorrelational) motion analysis directly to the visual signal. In order to extract motion information from microbalanced stimuli, Chubb and Sperling [(1988) Journal of the Optical Society of America, 5, 1986-2006] proposed that the human visual system performs a rectifying transformation on the visual signal prior to standard motion analysis. The current research employs two novel types of microbalanced stimuli: half-wave stimuli preserve motion information following half-wave rectification (with a threshold) but lose motion information following full-wave rectification; full-wave stimuli preserve motion information following full-wave rectification but lose motion information following half-wave rectification. Additionally, Fourier stimuli, ordinary square-wave gratings, were used to stimulate standard motion mechanisms. Psychometric functions (direction discrimination vs stimulus contrast) were obtained for each type of stimulus when presented alone, and when masked by each of the other stimuli (presented as moving masks and also as nonmoving, counterphase-flickering masks). RESULTS: given sufficient contrast, all three types of stimulus convey motion. However, only one-third of the population can perceive the motion of the half-wave stimulus. Observers are able to process the motion information contained in the Fourier stimulus slightly more efficiently than the information in the full-wave stimulus but are much less efficient in processing half-wave motion information. Moving masks are more effective than counterphase masks at hampering direction discrimination, indicating that some of the masking effect is interference between motion mechanisms, and some occurs at earlier stages. When either full-wave and Fourier or half-wave and Fourier gratings are presented simultaneously, there is a wide range of relative contrasts within which the

  19. Bleustein-Gulyaev-Shimizu surface acoustic waves in two-dimensional piezoelectric phononic crystals.

    PubMed

    Hsu, Jin-Chen; Wu, Tsung-Tsong

    2006-06-01

    In this paper, we present a study on the existence of Bleustein-Gulyaev-Shimizu piezoelectric surface acoustic waves in a two-dimensional piezoelectric phononic crystal (zinc oxide, ZnO, and cadmium-sulfide, CdS) using the plane wave expansion method. In the configuration of ZnO (100)/CdS(100) phononic crystal, the calculated results show that this type of surface waves has higher acoustic wave velocities, high electromechanical coupling coefficients, and larger band gap width than those of the Rayleigh surface waves and pseudosurface waves. In addition, we find that the folded modes of the Bleustein-Gulyaev-Shimizu surface waves have higher coupling coefficients.

  20. [Patch-testing methods: additional specialised or additional series].

    PubMed

    Cleenewerck, M-B

    2009-01-01

    The tests in the European standard battery must occasionally be supplemented by specialised or additional batteries, particularly where the contact allergy is thought to be of occupational origin. These additional batteries cover all allergens associated with various professional activities (hairdressing, baking, dentistry, printing, etc.) and with different classes of materials and chemical products (glue, plastic, rubber...). These additional tests may also include personal items used by patients on a daily basis such as cosmetics, shoes, plants, textiles and so on.

  1. Leading Wave Amplitude of a Tsunami

    NASA Astrophysics Data System (ADS)

    Kanoglu, U.

    2015-12-01

    Okal and Synolakis (EGU General Assembly 2015, Geophysical Research Abstracts-Vol. 17-7622) recently discussed that why the maximum amplitude of a tsunami might not occur for the first wave. Okal and Synolakis list observations from 2011 Japan tsunami, which reached to Papeete, Tahiti with a fourth wave being largest and 72 min later after the first wave; 1960 Chilean tsunami reached Hilo, Hawaii with a maximum wave arriving 1 hour later with a height of 5m, first wave being only 1.2m. Largest later waves is a problem not only for local authorities both in terms of warning to the public and rescue efforts but also mislead the public thinking that it is safe to return shoreline or evacuated site after arrival of the first wave. Okal and Synolakis considered Hammack's (1972, Ph.D. Dissertation, Calif. Inst. Tech., 261 pp., Pasadena) linear dispersive analytical solution with a tsunami generation through an uplifting of a circular plug on the ocean floor. They performed parametric study for the radius of the plug and the depth of the ocean since these are the independent scaling lengths in the problem. They identified transition distance, as the second wave being larger, regarding the parameters of the problem. Here, we extend their analysis to an initial wave field with a finite crest length and, in addition, to a most common tsunami initial wave form of N-wave as presented by Tadepalli and Synolakis (1994, Proc. R. Soc. A: Math. Phys. Eng. Sci., 445, 99-112). We compare our results with non-dispersive linear shallow water wave results as presented by Kanoglu et al. (2013, Proc. R. Soc. A: Math. Phys. Eng. Sci., 469, 20130015), investigating focusing feature. We discuss the results both in terms of leading wave amplitude and tsunami focusing. Acknowledgment: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no 603839 (Project ASTARTE - Assessment, Strategy and Risk

  2. Modal Waves Solved in Complex Wave Number

    NASA Astrophysics Data System (ADS)

    Xu, W.-J.; Jenot, F.; Ourak, M.

    2005-04-01

    A numerical algorithm is proposed for the resolution in complex domain of the ultrasonic modal waves from the characteristic equation of elastic structures. The method is applicable to any numerically available function given explicitly or implicitly. The complex root loci of the modal waves are constructed by varying other parameters. Different situations which can cause the roots searching and following failure are analysed and the corresponding solutions are proposed. The computation examples are given for a three layered adhesive joint and a composite plate.

  3. Additive manufacturing of optical components

    NASA Astrophysics Data System (ADS)

    Heinrich, Andreas; Rank, Manuel; Maillard, Philippe; Suckow, Anne; Bauckhage, Yannick; Rößler, Patrick; Lang, Johannes; Shariff, Fatin; Pekrul, Sven

    2016-08-01

    The development of additive manufacturing methods has enlarged rapidly in recent years. Thereby, the work mainly focuses on the realization of mechanical components, but the additive manufacturing technology offers a high potential in the field of optics as well. Owing to new design possibilities, completely new solutions are possible. This article briefly reviews and compares the most important additive manufacturing methods for polymer optics. Additionally, it points out the characteristics of additive manufactured polymer optics. Thereby, surface quality is of crucial importance. In order to improve it, appropriate post-processing steps are necessary (e.g. robot polishing or coating), which will be discussed. An essential part of this paper deals with various additive manufactured optical components and their use, especially in optical systems for shape metrology (e.g. borehole sensor, tilt sensor, freeform surface sensor, fisheye lens). The examples should demonstrate the potentials and limitations of optical components produced by additive manufacturing.

  4. Incorporating Experience Curves in Appliance Standards Analysis

    SciTech Connect

    Garbesi, Karina; Chan, Peter; Greenblatt, Jeffery; Kantner, Colleen; Lekov, Alex; Meyers, Stephen; Rosenquist, Gregory; Buskirk, Robert Van; Yang, Hung-Chia; Desroches, Louis-Benoit

    2011-10-31

    The technical analyses in support of U.S. energy conservation standards for residential appliances and commercial equipment have typically assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. There is, however, considerable evidence that this assumption does not reflect real market prices. Costs and prices generally fall in relation to cumulative production, a phenomenon known as experience and modeled by a fairly robust empirical experience curve. Using price data from the Bureau of Labor Statistics, and shipment data obtained as part of the standards analysis process, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These allow us to develop more representative appliance price projections than the assumption-based approach of constant prices. These experience curves were incorporated into recent energy conservation standards for these products. The impact on the national modeling can be significant, often increasing the net present value of potential standard levels in the analysis. In some cases a previously cost-negative potential standard level demonstrates a benefit when incorporating experience. These results imply that past energy conservation standards analyses may have undervalued the economic benefits of potential standard levels.

  5. Incorporation of Xenon in magmas at depth

    NASA Astrophysics Data System (ADS)

    Leroy, C.; Sanloup, C.; Bureau, H.; Schmidt, B.; Konopkova, Z.; Raepsaet, C.

    2014-12-01

    Incorporation of volatile elements in magmas is enhanced at high pressure. The dissolved volatiles affect in turn the physical and chemical properties of silicate melts. Understanding volatiles incorporation in magmas and their effect on the melt's structure can be approached by in situ characterizations such as X-ray diffraction or Raman spectroscopy.Here, we focus on Xenon (Xe) in order to constrain its past and modern geochemical cycles. Indeed the 129I/129Xe extinct isotopic system is used to constrain planetary and atmosphere formation models. Moreover, some studies propose that Xe is currently recycled from the atmosphere to the mantle.To study the solubility of Xe in silicate melts, we have performed in situ X-ray diffraction experiments on the synchrotron beam line P02 in PetraIII (DESY, Hamburg). Experiments were carried out using resistive heating diamond-anvil cells up to 7 GPa and 1300°C. Two compositions have been studied: a hydrous haplogranite (HPG) reference and a hydrous HPG doped with Xe. This composition is a magma analogue that is extremely well documented by petrological studies. Xenon can be identified on the radial distribution functions obtained by processing the x-ray diffraction data. Solubility mechanisms of Xe in silicate melts at depth will be discussed.

  6. Incorporating Plant Hydraulics Into Phenological Modeling

    NASA Astrophysics Data System (ADS)

    Savoy, P.; Mackay, D. S.

    2014-12-01

    Vegetation phenology is well studied in systems where temperature is the primary driver of change, such as temperate and boreal ecosystems. In order to accurately model phenology in water-limited systems it is necessary to consider the role of water stress on mediating phenology. While it is possible to use proxies for water stress, such as vapor pressure deficit (VPD), it is preferable to have a more direct link to the effects of water stress on plant physiology. One possible approach is to incorporate the physiological responses of plants to water stress into phenological models. The goal of this study is to examine the use of plant hydraulics to help predict phenology instead of using only meteorological variables. We used an ecosystem process model that incorporates plant hydraulics, the Terrestrial Regional Ecosystem Exchange Simulator (TREES), in order to model plant phenology based on hydraulic stress. Phenology submodels implemented within TREES included both those driven purely from environmental variables as well those modulated by plant hydraulics. Results showed that the use of plant hydraulics to predict phenology, instead of using VPD as a proxy of plant water stress, performed favorably in comparison to models driven by meteorological variables alone. The need for better representation of moisture stress on phenology was particularly apparent in water-limited systems and the inclusion of plant hydraulics into phenology models improved the predictions in these systems.

  7. Incorporating intelligence into structured radiology reports

    NASA Astrophysics Data System (ADS)

    Kahn, Charles E.

    2014-03-01

    The new standard for radiology reporting templates being developed through the Integrating the Healthcare Enterprise (IHE) and DICOM organizations defines the storage and exchange of reporting templates as Hypertext Markup Language version 5 (HTML5) documents. The use of HTML5 enables the incorporation of "dynamic HTML," in which documents can be altered in response to their content. HTML5 documents can employ JavaScript, the HTML Document Object Model (DOM), and external web services to create intelligent reporting templates. Several reporting templates were created to demonstrate the use of scripts to perform in-template calculations and decision support. For example, a template for adrenal CT was created to compute contrast washout percentage from input values of precontrast, dynamic postcontrast, and delayed adrenal nodule attenuation values; the washout value can used to classify an adrenal nodule as a benign cortical adenoma. Dynamic templates were developed to compute volumes and apply diagnostic criteria, such as those for determination of internal carotid artery stenosis. Although reporting systems need not use a web browser to render the templates or their contents, the use of JavaScript creates innumerable opportunities to construct highly sophisticated HTML5 reporting templates. This report demonstrates the ability to incorporate dynamic content to enhance the use of radiology reporting templates.

  8. Incorporated of tritiated water in fish

    SciTech Connect

    Sprous, D.G.; Fox, J.E.; Jackson, B.A.

    1989-01-01

    Tritiated water {sup 3}H{sub 2}O is routinely discharged into the environment near nuclear power plants and reactors. The radioactive water is rapidly equilibriated with cell water in the aquatic life forms. The purpose of this study was to determine the uptake of the radioactive hydrogen into the various lipid classes. Oak Ridge National Laboratory has been discharging tritiated water into White Oak Lake. Blue gill and mosquito fish from White Oak Lake were analyzed. An experimental fish tank with water having a specific activity of 1.2 {times} 10{sup 6} dpm of {sup 3}H/mL was set up. Mosquito fish were exposed to this level of radioactivity for thirty days. After this time the fish were lypolyzed an the lipids were extracted. The phospholipid fraction incorporated the greatest percentage of the radioactivity. Significant incorporation of activity was also seen in the triglyceride and cholesterol fractions. Phospholipids and cholesterol are important structural components of the cell, insuring persistence of the radioactivity in the organism. The long term effects are not known.

  9. Flexible ultrasonic transducers incorporating piezoelectric fibres.

    PubMed

    Harvey, Gerald; Gachagan, Anthony; Mackersie, John W; McCunnie, Thomas; Banks, Robert

    2009-09-01

    It is possible to produce a high-performance, flexible 1-3 connectivity piezoelectric ceramic composite with conventional methods but the process is difficult and time-consuming. Extensive finite element modeling was used to design a piezocomposite structure which incorporated randomly positioned piezoceramic fibers in a polymer matrix. Simple manufacturing techniques were developed which resulted in the production of large numbers of fully populated fiber composites that offered performance comparable with a conventional 1-3 piezocomposite. A modified process facilitated the production of efficient fiber piezocomposite elements separated by polymer channels which conformed to a highly flexible (13 mm radius of curvature), 2-D matrix array configuration. This arrangement has been termed a Composite Element Composite Array Transducer, or CECAT. These devices were evaluated in terms of their impedance spectra, pulse-echo response, and surface displacement characteristics. The random piezoceramic fiber arrangements showed comparable sensitivity and bandwidth to periodic devices while minimizing the parasitic interpillar modes associated with periodic structures. Investigations have indicated that CECAT arrays constructed with 250 microm diameter fibers can be operated at frequencies of up to 3 MHz and transducers incorporating 10 microm diameter fibers can extend the frequency range above 6 MHz. Conversely, improved low-frequency devices can be produced with taller pillars than possible with conventional manufacturing techniques. PMID:19812003

  10. Surface-Engineered Graphene Quantum Dots Incorporated into Polymer Layers for High Performance Organic Photovoltaics

    PubMed Central

    Kim, Jung Kyu; Kim, Sang Jin; Park, Myung Jin; Bae, Sukang; Cho, Sung-Pyo; Du, Qing Guo; Wang, Dong Hwan; Park, Jong Hyeok; Hong, Byung Hee

    2015-01-01

    Graphene quantum dots (GQDs), a newly emerging 0-dimensional graphene based material, have been widely exploited in optoelectronic devices due to their tunable optical and electronic properties depending on their functional groups. Moreover, the dispersibility of GQDs in common solvents depending on hydrophobicity or hydrophilicity can be controlled by chemical functionalization, which is particularly important for homogeneous incorporation into various polymer layers. Here we report that a surface-engineered GQD-incorporated polymer photovoltaic device shows enhanced power conversion efficiency (PCE), where the oxygen-related functionalization of GQDs enabled good dispersity in a PEDOT:PSS hole extraction layer, leading to significantly improved short circuit current density (Jsc) value. To maximize the PCE of the device, hydrophobic GQDs that are hydrothermally reduced (rGQD) were additionally incorporated in a bulk-heterojunction layer, which is found to promote a synergistic effect with the GQD-incorporated hole extraction layer. PMID:26392211

  11. Strain engineering to prevent norleucine incorporation during recombinant protein production in Escherichia coli.

    PubMed

    Veeravalli, Karthik; Laird, Michael W; Fedesco, Mark; Zhang, Yu; Yu, X Christopher

    2015-01-01

    Incorporation of norleucine in place of methionine residues during recombinant protein production in Escherichia coli is well known. Continuous feeding of methionine is commonly used in E. coli recombinant protein production processes to prevent norleucine incorporation. Although this strategy is effective in preventing norleucine incorporation, there are several disadvantages associated with continuous feeding. Continuous feeding increases the operational complexity and the overall cost of the fermentation process. In addition, the continuous feed leads to undesirable dilution of the fermentation medium possibly resulting in lower cell densities and recombinant protein yields. In this work, the genomes of three E. coli hosts were engineered by introducing chromosomal mutations that result in methionine overproduction in the cell. The recombinant protein purified from the fermentations using the methionine overproducing hosts had no norleucine incorporation. Furthermore, these studies demonstrated that the fermentations using one of the methionine overproducing hosts exhibited comparable fermentation performance as the control host in three different recombinant protein production processes. PMID:25315437

  12. Non-local crime density estimation incorporating housing information

    PubMed Central

    Woodworth, J. T.; Mohler, G. O.; Bertozzi, A. L.; Brantingham, P. J.

    2014-01-01

    Given a discrete sample of event locations, we wish to produce a probability density that models the relative probability of events occurring in a spatial domain. Standard density estimation techniques do not incorporate priors informed by spatial data. Such methods can result in assigning significant positive probability to locations where events cannot realistically occur. In particular, when modelling residential burglaries, standard density estimation can predict residential burglaries occurring where there are no residences. Incorporating the spatial data can inform the valid region for the density. When modelling very few events, additional priors can help to correctly fill in the gaps. Learning and enforcing correlation between spatial data and event data can yield better estimates from fewer events. We propose a non-local version of maximum penalized likelihood estimation based on the H1 Sobolev seminorm regularizer that computes non-local weights from spatial data to obtain more spatially accurate density estimates. We evaluate this method in application to a residential burglary dataset from San Fernando Valley with the non-local weights informed by housing data or a satellite image. PMID:25288817

  13. Incorporating computational resources in a cancer research program

    PubMed Central

    Woods, Nicholas T.; Jhuraney, Ankita; Monteiro, Alvaro N.A.

    2015-01-01

    Recent technological advances have transformed cancer genetics research. These advances have served as the basis for the generation of a number of richly annotated datasets relevant to the cancer geneticist. In addition, many of these technologies are now within reach of smaller laboratories to answer specific biological questions. Thus, one of the most pressing issues facing an experimental cancer biology research program in genetics is incorporating data from multiple sources to annotate, visualize, and analyze the system under study. Fortunately, there are several computational resources to aid in this process. However, a significant effort is required to adapt a molecular biology-based research program to take advantage of these datasets. Here, we discuss the lessons learned in our laboratory and share several recommendations to make this transition effectively. This article is not meant to be a comprehensive evaluation of all the available resources, but rather highlight those that we have incorporated into our laboratory and how to choose the most appropriate ones for your research program. PMID:25324189

  14. Incorporation of small molecular weight active agents into polymeric components.

    PubMed

    Iconomopoulou, Sofia M; Kallitsis, Joannis K; Voyiatzis, George A

    2008-01-01

    The incorporation of small molecular weight active agents into polymeric matrixes bearing controlled release characteristics represents an interesting strategy with numerous useful applications. Antimicrobials, biocides, fungicides or drugs, encapsulated into erodible or non-erodible polymeric micro-spheres, micro-capsules and micro-shells or/and embedded into continuous polymeric matrixes, are controlled released either by particular degradation routes or/and by specific stimuli. Cross-linking, curing or micro-porosity generating agents acting during polymerization impart additional controlled encapsulation characteristics to the active substances. Release modulating agents, like retardants or carrier materials used as vehicles are often encapsulated into microspheres or dispersed within polymeric compositions for the controlled introduction of an active agent into a liquid-based medium. The aim of this review is to reveal relevant strategies reported in recent patents on the encapsulation or incorporation of low molecular weight active agents into the matrix of polymers bearing controlled release characteristics. The inventions described implicate the formation of both erodible and non erodible polymer microparticles that contain active ingredients. Modification of polymer matrix and inorganic porous carriers represent pertinent major strategies that have been also developed and patented.

  15. Low coefficient of thermal expansion polyimides containing metal ion additives

    NASA Technical Reports Server (NTRS)

    Stoakley, D. M.; St. Clair, A. K.

    1992-01-01

    Polyimides have become widely used as high performance polymers as a result of their excellent thermal stability and toughness. However, lowering their coefficient of thermal expansion (CTE) would increase their usefulness for aerospace and electronic applications where dimensional stability is a requirement. The incorporation of metal ion-containing additives into polyimides, resulting in significantly lowered CTE's, has been studied. Various metal ion additives have been added to both polyamic acid resins and soluble polyimide solutions in the concentration range of 4-23 weight percent. The incorporation of these metal ions has resulted in reductions in the CTE's of the control polyimides of 12 percent to over 100 percent depending on the choice of additive and its concentration.

  16. 15 Years of Wave Height Data Assimilation

    NASA Astrophysics Data System (ADS)

    Janssen, P.

    2006-07-01

    Over the past fiffteen years there has been a continuous interplay between ocean wave forecasting and altimeter data resulting in improvemen ts in both. The prospect of global observations of wind and waves gave a significan t stimulus to wave model development, while the need to have reliab le wav e predictions stimu lated the d evelopment of altimeter wind and wave products. This p aper covers the following: - Altimeter W ave Height D ata Assimilation of altimeter wave height data is of vital importance for the quality of the wave analysis and ocean wave forecasting. In addition, these data are a great h elp in diagnosing wave model problems. Furthermore th ey have great value in ob taining a g lobal wave climato logy. -Altimeter W ind Sp eed D ata Wind speed data are important for mon itor ing the quality of modelled surface w ind. Recen tly, the 'classical' W itter and Ch elton (1991) retriev al algorithm for wind speed (σ0 = ƒ(U10))has been extended by includ ing sea state eff ects and has been in troduced for Jason. On the other hand, th e classical scheme was improved by Abdalla (2006) and introduced for ENVISAT. Th e Abdalla algorithm is shown to perform better, however . Altimeter w indspeed data h ave the potential to be of great value in hurricane conditions as w ell. -Tsunamis An altimeter can ind eed observe tsunami even ts, but there is doubt th at this may be of value for an early warning system.

  17. Oceanic-wave-measurement system

    NASA Technical Reports Server (NTRS)

    Holmes, J. F.; Miles, R. T.

    1980-01-01

    Barometer mounted on bouy senses wave heights. As wave motion raises and lowers barometer, pressure differential is proportional to wave height. Monitoring circuit samples barometer output every half cycle of wave motion and adds magnitudes of adjacent positive and negative peaks. Resulting output signals, proportional to wave height, are transmitted to central monitoring station.

  18. Structure of velocity distributions in shock waves in granular gases with extension to molecular gases

    NASA Astrophysics Data System (ADS)

    Vilquin, A.; Boudet, J. F.; Kellay, H.

    2016-08-01

    Velocity distributions in normal shock waves obtained in dilute granular flows are studied. These distributions cannot be described by a simple functional shape and are believed to be bimodal. Our results show that these distributions are not strictly bimodal but a trimodal distribution is shown to be sufficient. The usual Mott-Smith bimodal description of these distributions, developed for molecular gases, and based on the coexistence of two subpopulations (a supersonic and a subsonic population) in the shock front, can be modified by adding a third subpopulation. Our experiments show that this additional population results from collisions between the supersonic and subsonic subpopulations. We propose a simple approach incorporating the role of this third intermediate population to model the measured probability distributions and apply it to granular shocks as well as shocks in molecular gases.

  19. Structure of velocity distributions in shock waves in granular gases with extension to molecular gases.

    PubMed

    Vilquin, A; Boudet, J F; Kellay, H

    2016-08-01

    Velocity distributions in normal shock waves obtained in dilute granular flows are studied. These distributions cannot be described by a simple functional shape and are believed to be bimodal. Our results show that these distributions are not strictly bimodal but a trimodal distribution is shown to be sufficient. The usual Mott-Smith bimodal description of these distributions, developed for molecular gases, and based on the coexistence of two subpopulations (a supersonic and a subsonic population) in the shock front, can be modified by adding a third subpopulation. Our experiments show that this additional population results from collisions between the supersonic and subsonic subpopulations. We propose a simple approach incorporating the role of this third intermediate population to model the measured probability distributions and apply it to granular shocks as well as shocks in molecular gases. PMID:27627378

  20. A mesoscale gravity wave event observed during CCOPE. III - Wave environment and probable source mechanisms

    NASA Technical Reports Server (NTRS)

    Koch, Steven E.; Dorian, Paul B.

    1988-01-01

    The multiscale environment of gravity wave events and the probable mechanisms of their origin are examined on the basis of observations taken during the Cooperative Convective Precipitation Experiment in extreme eastern Montana, during the period from 1200 UTC July 11, 1981, to 0500 UTC July 12. During this time, two distinct gravity wave episodes were diagnosed. The results of the analysis of the evolving structures in the subsynoptic-scale and mesoscale environments indicate that the observed mesoscale gravity waves were generated by geostrophic adjustment processes, with additional energy supplied through interaction with the critical level; their coherence was maintained through a ducting mechanism.