Energy Technology Data Exchange (ETDEWEB)
The contents include: Detailed index for 1991; Data for November 1991--Solar-terrestrial environment, IUWDS alert periods (advance and worldwide), Solar activity indices, Solar flares, Solar radio emission, Stanford mean solar magnetic field; Data for October 1991--Solar active regions, Sudden ionospheric disturbances, Solar radio spectral observations, Cosmic ray measurements by neutron monitor, Geomagnetic indices; Late data--Cosmic ray measurements by neutron monitor (Climax February and May 1990, Deep River May-August 1991), Geomagnetic indices (Sudden commencements/Solar flare effects January-May 1991); Errata--August 1991 Geomagnetic activity indices.
1991-12-01
Energy Technology Data Exchange (ETDEWEB)
Contents include: index for 1970-1980; January 1981 data -- alert periods, daily solar indices, solar flares, solar radio emission, coronal holes, inferred interplanetary magnetic field polarities, mean solar magnetic field, spacecraft observations, December 1980 data -- daily solar-activity centers, sudden ionospheric disturbances, spacecraft observations, solar radio emission, cosmic rays, geomagnetic indices, radio-propagation indices; late data -- solar radio emission November, December 1980, spacecraft observations November 1980, cosmic rays, Huancayo Oct 1980 -- climax, alert, Deep River Nov 1980.
1981-02-01
Solar neutrinos, solar flares, solar activity cycle and the proton decay
It is shown that there may be a correlation between the galactic cosmic rays and the solar neutrino
1985-01-01
The AMPTE program's contribution to studies of the solar wind-magnetosphere-ionosphere interaction
Energy Technology Data Exchange (ETDEWEB)
The Active Magnetospheric Particle Tracer Explorers (AMPTE) program provided important information on the behavior of clouds of plasma artificially injected into the solar wind and the earth's magnetosphere. Now that the releases are over, data from the satellites are being analyzed to investigate the processes by which the ambient solar wind mass, momentum, and energy are transferred to the magnetosphere. Work in progress at APL indicates that the solar wind is much more inhomogeneous than previously believed, that the solar wind constantly buffets the magnetosphere, and that ground observers may remotely sense these interactions as geomagnetic pulsations. 8 refs.
1990-12-01
International Nuclear Information System (INIS)
We present 14 years of contemporaneous photometric and spectroscopic observations of 28 solar analog stars, taken with the Tennessee State University Automatic Photometric Telescopes at Fairborn Observatory and the Solar-Stellar Spectrograph at Lowell Observatory. These are the best observed and most nearly Sun-like of the targets in our magnitude-limited (V #<=# 7.5) sample. The correlations between luminosity and activity reveal the expected inverse activity-brightness correlations for active stars. Strong direct correlations between activity and brightness are not prevalent for the less active solar age stars, but are precision limited. The Sun does not appear to have unusually low photometric variability when compared with the most Sun-like inactive ...
2009-07-01
Observing Evolution in the Supergranular Length Scale During Periods of Low Solar Activity
We present the initial results of an observational study into the variation of the dominant length-scale of quiet solar emission: supergranulation. This length-scale reflects the radiative energy in the plasma of the upper solar chromosphere and transition region at the magnetic network boundaries forming as a result of the relentless interaction of magnetic fields and convective motions of the Sun's interior. We demonstrate that a net difference of ~0.5Mm in the supergranular emission length-scale occurs when comparing observations cycle 22/23 and cycle 23/24 minima. This variation in scale is reproduced in the datasets of multiple space- and ground-based instruments and using different diagnostic measures. By means of extension, we consider the variation of the supergranular length-scale over multiple solar minima by analyzing a subset of the Mt Wilson Solar ...
2011-01-01
Astronomical and astrophysical research activities of the Institute of Astronomy
Energy Technology Data Exchange (ETDEWEB)
Observational work on quasars, galaxies, and stars is summarized. Theoretical studies covering stars and stellar evolution, galaxies, clusters and cosmology, high energy astrophysics the solar system and the Sun are described. (ESA)
1980-01-01
British Library Electronic Table of Contents (United Kingdom)
We present a forward modelling technique for calculating the surface X-ray spectra for a variety of lunar terrains. Our calculations considered variations in solar fluxes from solar quiescent condition to large flare activity (M1 flare), and expected elemental concentrations in the target, as well as yield, instrumental, and viewing geometry parameters for X-ray induced fluorescence from the lunar surface. Additionally, we present estimates of anticipated XRF signals from prominent Ka lines observable by a collimated 14cm2 X-ray detector from a 100km lunar orbit with 20km spatial resolution. Our results show that Mg, Al and Si characteristic Ka lines can be observed for all solar conditions. The Ca Ka lines line can be differentiated from a fixed background during more energetic solar cond...
2010-01-01
Solar effects on communications
International Nuclear Information System (INIS)
This paper focuses on potential effects of solar phenomena on communication systems used by the electric utility industry. It begins with a discussion of solar phenomena fundamentals and discussion of the interaction between solar emissions and the earth's ionosphere and magnetosphere. It continues with a discussion of the resulting impacts on communication systems including radio, satellite, wireline, fiber optic, and powerline systems and concludes with a discussion of mitigation techniques and a call for observers to report suspected solar impact experiencexperiences.
The genesis solar-wind sample return mission
Energy Technology Data Exchange (ETDEWEB)
The compositions of the Earth's crust and mantle, and those of the Moon and Mars, are relatively well known both isotopically and elementally. The same is true of our knowledge of the asteroid belt composition, based on meteorite analyses. Remote measurements of Venus, the Jovian atmosphere, and the outer planet moons, have provided some estimates of their compositions. The Sun constitutes a large majority, > 99%, of all the matter in the solar system. The elemental composition of the photosphere, the visible 'surface' of the Sun, is constrained by absorption lines produced by particles above the surface. Abundances for many elements are reported to the {+-}10 or 20% accuracy level. However, the abundances of other important elements, such as neon, cannot be determined in this way due to a relative lack of atomic states at low excitation energies. Additionally and most importantly, the isotopic composition of the Sun cannot be ...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
The organization of organic semiconductor molecules in the active layer of organic electronic devices has important consequences to overall device performance. This is due to the fact that molecular organization directly affects charge carrier mobility of the material. Organic field-effect transistor (OFET) performance is driven by high charge carrier mobility while bulk heterojunction (BHJ) solar cells require balanced hole and electron transport. By investigating the properties and device performance of three structural variations of the fluorenyl hexa-peri-hexabenzocoronene (FHBC) material, the importance of molecular organization to device performance was highlighted. It is clear from {sup 1}H NMR and 2D wide-angle X-ray scattering (2D WAXS) experiments that the sterically demanding 9,9-dioctylfluorene groups are preventing {pi}-{pi} intermolecular contact in the hexakis-substituted FHBC 4. For bis-substituted FHBC compounds 5 and 6, ...
2010-03-24
Energy Technology Data Exchange (ETDEWEB)
Four topics in nuclear astrophysics, namely; pulsars, star evolution, nucleosynthesis and solar neutrinos are reviewed through the discussion of the observational data.
1982-09-01
Energy Technology Data Exchange (ETDEWEB)
A new band gap profile (exponential profile) for the active layer of the a-SiGe:H single junction cell has been designed and experimentally demonstrated. By computer simulations we show how bending the grading of the band gap in the i-layer contributes to the enhancement of the carrier collection, improving the fill factor and efficiency. The differences observed between experiments and simulations are studied using Rutherford Backscattering Spectrometry (RBS). The results highlight weak points during the deposition process, whose control enables us to bring together experimental and computational results.
2004-01-25
Gamma ray observations of the solar system
Energy Technology Data Exchange (ETDEWEB)
Two general categories are discussed concerning the evolution of the solar system: the dualistic view, the planetesimal approach and the monistic view, the nebular hypothesis. The major points of each view are given and the models that are developed from these views are described. Possible applications of gamma ray astronomical observations to the question of the dynamic evolution of the solar system are discussed.
1981-01-01
Long-term modulation of cosmic rays in interplanetary magnetic turbulence
Energy Technology Data Exchange (ETDEWEB)
Long-term modulation of galactic cosmic rays in interplanetary magnetic field (IMF) turbulence is a fundamental subject for understanding the connection between cosmic ray transport and solar activity. The discovery of a new cosmic ray modulation phenomenon is reported. Analysis of neutron monitor data has revealed that the difference in amplitude of the cosmic ray diurnal anisotropy for IMF sectors directed toward and away from the Sun displays a solar cycle variation. Neutron monitor data recorded at Climax, Deep River, Hyancayo, Kiel, Mt. Washington, and Swarthmore/Newark over the period 1957 to 1988 show that the amplitude difference varied between approximately 0.1 to -0.1 percent, with peaks in 1960, 1972, and 1982. A theoretical expression for this difference was derived from a three-dimensional model. Analysis also showed that the latitudinal density gradient of cosmic rays changed between 1.6 and -1.6 percent/AU ...
1989-01-01
Energy Technology Data Exchange (ETDEWEB)
A compact and energy independent solar-powered refrigeration unit was to be developed to store and transport small quantities of high-quality commodities needing refrigeration. This unit comprises the following matched components: thermo-electrical refrigerator unit, solar generator and transport equipment. The solar generator is a specially developed panel with 36 cells. This unit may best be used in human medicine, veterinary medicine, environmental protection analysis, laboratories and leisure time activities. (BWI)
1994-01-01
Several observational studies suggest that solar wind dynamic pressure fluctuations can drive magnetospheric ultra-low frequency (ULF) waves on the dayside. To investigate this causal relationship, we present results from Lyon-Fedder-Mobarry (LFM) global, three-dimensional magnetohydrodynamic (MHD) simulations of the solar wind-magnetosphere interaction. These simulations are driven with synthetic solar wind input conditions, where idealized ULF dynamic pressure fluctuations are embedded in the upstream solar wind. In three of the simulations, a monochromatic, sinusoidal ULF oscillation is introduced into the solar wind dynamic pressure time series. In the fourth simulation, a continuum of ULF fluctuations over the 0-50 mHz frequency band is introduced into the solar wind dynamic pressure time series. In this numerical experiment, the ...
2010-01-01
Solar thermal electricity in 1998: An IEA/SolarPACES summary of status and future prospects
Energy Technology Data Exchange (ETDEWEB)
Research and development activities sponsored by countries within the International Energy Agency`s solar thermal working group. SolarPACES, have helped reduce the cost of solar thermal systems to one-fifth that of the early pilot plants. Continued technological improvements are currently being proven in next-generation demonstration plants. These advances, along with cost reductions made possible by scale-up to larger production and construction of a succession of power plants, have made solar thermal systems the lowest-cost solar energy in the world and promise cost-competitiveness with fossil-fuel plants in the future. Solar thermal technologies are appropriate for a wide range of applications, including dispatchable central-station power plants where they can meet peak-load to near-base-load needs of a utility, and distributed, modular ...
1998-07-01
A new high-temperature solar research furnace
Energy Technology Data Exchange (ETDEWEB)
A new highly concentrating solar research furnace has recently been completed at the University of Minnesota. The experimentally observed flux concentration ratio, at small aperture, of a cavity receiver is about 7000. The furnace embodies features which may be of interest to others in the solar energy community. This paper describes its construction and performance.
1983-08-01
Energy Technology Data Exchange (ETDEWEB)
A rocket borne experiment to measure the temperature structure of the inner solar corona via the doppler broadening of the resonance hydrogen Lyman-..cap alpha.. (lambda1216A) radiation scattered by ambient neutral hydrogen atoms was attempted during the 16 Feb 1980 solar eclipse. Two Nike-Black Brant V sounding rockets carrying instrumented payloads were launched into the path of the advancing eclipse umbra from the San Marco satellite launch platform 3 miles off the east coast of Kenya.
1981-01-01
Employing exergy-optimized pin fins in the design of an absorber in a solar air heater
Energy Technology Data Exchange (ETDEWEB)
Fins serve as heat transfer augmentation features in solar air heaters; however, they increase pressure drop in flow channels. Pin fins are relatively good heat transfer augmentation features with superior aerodynamic performance, and as a result find application in some solar air heaters. The exergy optimization method is employed in sizing the pin fin. Results indicate that high efficiency of the optimized fin improves the heat absorption and dissipation potential of a solar air heater. With optimum fin efficiency and superior absorptive coating quality, useful energy losses can be minimized. Some important observations pertinent in design are made. (author)
2010-02-15
Applications of solar heat in agriculture and industry
Energy Technology Data Exchange (ETDEWEB)
The production of process heat for agriculture and industry is one of the applications of solar energy which is very close to economic competitivity. Solar collectors can be produced at a reasonable cost by existing industries and are used optimally through applications which present a good time correlation between energy needs and the possible production of solar heat. This article studies heat consumption in industrial and agricultural sectors, gives hints on collectors choices, rates the different projects by simulation taking into account the nature of agricultural and industrial activities and the geographical location of the projects, examines when the equipment first competes according to hypotheses made on the various energy and collectors cost.
1980-01-01
International heliophysical year and basic space science in West Asia
This paper summarizes the IHY and BSS activities in West Asia and their importance in many Arab countries, such as Algeria, Egypt, Iraq, Jordan, Kuwait, Qatar, Saudi Arabia, UAE, etc. BSS future plans for some of these countries are as follows: It is proposed by the astronomers from the Arabian Gulf Region to build the Gulf Observatory on top of Jabal Shams (2980 msl) which will have a 2-3 m optical telescope. Libya signed a contract with a French company for building an observatory which will have a 2-m optical robotic telescope. It is also proposed to rebuild the Iraqi National Astronomical Observatory (INAO) which was destroyed during the two wars. It is planned to build a 5-6 m optical telescope and a small solar telescope on the top of Korek mountain, which has excellent observing conditions.
2007-12-01
The Development of a Neutral Particle Detector for Observations of the Thermosphere
One of the least understood regions of the upper atmosphere is the thermosphere, principally due to the difficulty of making observations. The neutral atmosphere is known to be highly variable, and its composition and density varies by several orders of magnitude due to solar activity, diurnal cycles, latitude, geomagnetic activity, and gravity waves. In the past, most in-situ measurements of the neutral atmosphere have utilized detectors that are dependent on arrival angle and energy accommodation of incoming species, so that information related to nascent velocity distribution and reactive species abundances is often masked. This paper will review design concepts and laboratory tests related to the development of a novel open-ionizer, neutral particle detector for space environment measurements which can overcome these limitations. The sensor features a very large field-of-view suitable for ...
2006-12-01
Stereoscopic observations of a solar hard x-ray flare with Ulysses, PVO, GRO and Yohkoh spacecraft
Energy Technology Data Exchange (ETDEWEB)
Hard X-ray/gamma-ray spectrometers aboard two interplanetary spacecraft, Ulysses and Pioneer Venus Orbiter (PVO), and two near-Earth spacecraft, Yohkoh and Compton Gamma Ray Observatory (GRO/BATSE), are currently in operation. A unique set of circumstances have permitted the observation of the 15 November 1991 (2238 UT) flare by all the four instruments. This intense flare (GOES class X 1.5) was associated with the bright (3B) H-alpha flare located on the disk (S13, W19) in the active region 6919. At the time of the flare, the Ulysses and PVO spacecraft were located respectively 101[degree] and 52[degree] west of the Sun-Earth line. Thus the view angles for the PVO and Ulysses instruments were quite different from those of the near-Earth instruments on GRO and Yohkoh. The preliminary photon energy spectra observed by the four instruments at different times during the flare will be presented and their implications regarding ...
1992-01-01
Energy Technology Data Exchange (ETDEWEB)
For a solar cell, in order to minimize the loss of incident light, transparent glass or plastic material is used at the incident part. When a solar cell is watched from the light incident part, a silicon base material is directly observed with either block or brown color only. This invention enables a solar cell to give brighter color on the incident surface by placing a reflective film which reflects only the light of specific wavelength, without reducing the efficiency of the solar cell. This reflective film consists of multi-layered dielectric with 12 layers and alternative combination of highly refractive and less refractive substances. Highly refractive layer is Y/sub 2/O/sub 3/ with refractive index 1.74 and the less refractive layer is SiO/sub 2/ with refractive index 1.45. (5 figs)
1987-09-19
Deep-level defects and numerical simulation of radiation damage in GaAs solar cells
Energy Technology Data Exchange (ETDEWEB)
A review of the deep-level defects observed in both electron- and proton-irradiated GaAs solar cells is presented. Studies of the effects of periodic and continuous thermal annealing on the radiation-induced electron and hole traps and the recombination parameters in GaAs solar cells were made for a wide range of electron and proton energies, fluence, annealing temperature and annealing time. A refined model for numerical simulations of the displacement damage was developed for computing the defect density and the cell parameters in the electron- and proton-irradiated GaAs solar cells. Excellent agreement was obtained between the calculated values and the experimental data for the proton-irradiated GaAs solar cells. (orig.).
1991-09-01
Thin film GaAs solar cells on glass substrates by epitaxial liftoff
Energy Technology Data Exchange (ETDEWEB)
In this work, we describe the fabrication and operating characteristics of GaAs/AlGaAs thin film solar cells processed by the epitaxial liftoff (ELO) technique. This technique allows the transfer of these cells onto glass substrates. The performance of the lifted-off solar cell is demonstrated by means of electrical measurements under both dark and illuminated conditions. We have also optimized the light trapping conditions in this direct-gap material. The results show that good solar absorption is possible in active layers as thin as 0.32 {mu}m. In such a thin solar cell, the open circuit voltage would be enhanced. We believe that the combination of an epitaxial liftoff thin GaAs film, and nano-texturing can lead to record breaking performance. {copyright} {ital 1997 American Institute of Physics.}
1997-02-01
Environmental data for sites in the National Solar Data Network
Energy Technology Data Exchange (ETDEWEB)
The Detartment of Energy's National Solar Data Program established solar energy systems in residential and commercial buildings across the United States. These solar sites are linked to Vitro Laboratories Division's computer in the National Solar Data Network (NSDN). Vitro collects and analyzes data from this network to determine the thermal performance of each of the solar systems. Environmental information collected at the sites for the month of August 1980 is presented. The environmental data for the NSDN are presented in the form of tables for each solar site. The solar sites are grouped into 12 zones, each of which consists of several adjacent states. The solar energy sites are in alphabetical sequence within each zone. The tables provide available meteorological data for reporting sites in the ...
1980-08-01
Relation Between Myocardial Infarction Deaths and Solar Activity in Mexico
We study the daily incidence of myocardial infarction deaths in Mexico for 4 years (1996-99) with a total of 129 917 cases in all the country, collected at the General Directorate of Epidemiology (National Ministry of Health). We divided the cases by sex and age and perform two kinds of analysis. First, we did an spectral analysis using the Maximum Entropy Method, considering the complete period, and minimum and maximum epochs of solar activity. The results show that the most persistent periodicity at higher frequencies in the myocardial infarction death occurrence is that of seven days. Considering the solar cycle phases, we found that during solar minimum times some frequencies are not detectable compared with solar maximum epochs, particularly that of seven days. Biological rhythms close to seven days, the circaseptans, are in general thought to be only the result of the social ...
2002-05-01
Energy Technology Data Exchange (ETDEWEB)
This paper reports the study results on the standard weather data necessary for simulation of PV power generation systems in fiscal 1994. In the study on the selection criterion of the standard weather data from the viewpoint of PV power generation systems, three typical years are used; a year with average solar radiation, and two years with extremely less and more solar radiation for safe simulation. The standard weather data are arranged for output calculation of PV power generation systems by selecting the most typical year based on long-term observation data. The data to be arranged are as follows; total, direct and scattered solar radiations incident upon a horizontal surface, solar radiation upon a slope surface, sunshine duration, air temperature, wind direction, wind velocity, amount of precipitation, and snow depth. For arrangement of the nationwide standard weather data, ...
1994-12-01
Environmental data for sites in the National Solar Data Network
Energy Technology Data Exchange (ETDEWEB)
The environmental data for the NSDN are presented in the form of tables for each solar site. The solar sites are grouped into 12 zones, each of which consists of several adjacent states. The solar energy sites are in alphabetical sequence within each zone. The tables provide available meteorological data for reporting sites in the NSDN as follows: Insolation - the insolation table presents the total, diffuse, direct, maximum, and extra-terrestrial radiation for the solar site. It also shows the ratio of total extra-terrestrial radiation, as a percent. Temperature - the temperature table gives the average, daytime, nightime, maximum, minimum and inlet-water temperatures for the solar site. Additional tables are presented for some of these NSDN sites, supplying either wind or relative humidity data, or both. Wind - all of the passive and some of the active ...
1980-12-01
Wind loss prevention for open cavity solar receivers
Energy Technology Data Exchange (ETDEWEB)
Apparatus for minimizing thermal loss in a windowless, open cavity solar receiver due to airflow at the receiver aperture includes means for deflecting wind away from the cavity opening such that flow stream reattachment occurs away from the receiver aperture to provide a dead air zone at the cavity opening. This prevents turbulent-mixing airflow exchange between ambient air and heated air within the solar receiver. The wind deflector apparatus includes either a passive annular deflection foil at the receiver aperture, or an active device for producing an outwardly projected air jet at the receiver aperture.
1982-01-26
Energy Technology Data Exchange (ETDEWEB)
Experiments were carried out to determine the adsorption capability of some commercial activated and non-activated charcoal samples with methanol to select the most favourable pair to be used in a solar adsorption refrigeration system. The results obtained are presented. A simple method has been used to enhance the adsorption capability of the lumpwood charcoal. (Author)
1994-01-01
Uncertainty analysis of high altitude aircraft air mass zero solar cell calibration
Energy Technology Data Exchange (ETDEWEB)
Recently the ISO standards organization has requested the PV community to establish AMO calibration methodologies for space solar cells. The PV community responded by organizing a series of workshops to review and recommend AMO calibration techniques. One of the activities of the workshop is to review the various calibration methodologies and conduct a comprehensive uncertainty analysis of each method. This paper outlines NASA`s methodology of AMO calibration using the high altitude aircraft method.
1997-12-31
Gas fixation solar cell using gas diffusion semiconductor electrode
Energy Technology Data Exchange (ETDEWEB)
A gas diffusion semiconductor electrode and solar cell and a process for gaseous fixation, such as nitrogen photoreduction, CO/sub 2/ photoreduction and fuel gas photo-oxidation are described. The gas diffusion photosensitive electrode has a central electrolyte porous matrix with an activated semiconductor material on one side adapted to be in contact with an electrolyte and a hydrophobic gas diffusion region on the opposite side adapted to be in contact with a supply of molecular gas.
1980-12-23
Building design using the energy nomographs
Energy Technology Data Exchange (ETDEWEB)
Today's building industry is promoting the use of renewable sources of energy to heat, cool, and illuminate commercial buildings. Societies such as the International Solar Energy Society sponsor conferences such as this one to share knowledge and experience in the area of solar energy. However, the technologies presented here assume a need for heating, cooling or illumination. A simple technique is presented for determining the actual heating, cooling, and lighting requirements for commercial buildings, and for reducing those requirements through proper building design before applying solar technologies. The energy nomographs are a graphic energy design tool developed to aid designers in making cost effective decisions about energy alternatives early in the design process. Reducing loads at this point can help reduce the expense of a passive or active solar system which is ...
1983-06-01
Early forecast of radiation-hazardous solar cosmic ray fluxes on the neutron monitors data
The system of the early forecast of radiation hazardous fluxes of solar cosmic rays in space on the basis of the real time neutron monitors data obtained by the NMDB (Neutron Monitor Data Base) network is created. The forecast system is based on a short cut technique of definition of a spectrum of solar protons from the data of the limited number of neutron monitor stations and with a simplified procedure of accounts. It is shown that the results of computations of solar proton spectra with the short-cut technique little differ from spectra obtained with a complete technique at energies less than 5 GeV. Thus the good agreement between derived from the neutron monitor data intensities of solar protons in an energy range of hundreds MeV with the data of direct measurements of solar protons at GOES-11 spacecraft is observed. The maximum of increase on neutron ...
2010-01-01
Discovery of interstellar rubidium
Energy Technology Data Exchange (ETDEWEB)
We have discovered interstellar rubidium by observing the resonance line of Rb I at 7800 A toward zeta Oph. This is the heaviest element yet detected within the interstellar medium, and our detection of this element is important for understanding the history of nucleosynthesis in the solar neighborhood.
1981-12-01
Line intensity enhancements in stellar coronal X-ray spectra due to opacity effects
Context. The I(15.01 A)/I(16.78 A) emission line intensity ratio in Fe XVII has been reported to deviate from its theoretical value in solar and stellar X-ray spectra. This is attributed to opacity in the 15.01 A line, leading to a reduction in its intensity, and was interpreted in terms of a geometry in which the emitters and absorbers are spatially distinct. Aims. We study the I(15.01 A)/I(16.78 A) intensity ratio for the active cool dwarf EV Lac, in both flare and quiescent spectra. Methods. The observations were obtained with the Reflection Grating Spectrometer on the XMM-Newton satellite. The emission measure distribution versus temperature reconstruction technique is used for our analysis. Results. We find that the 15.01 A line exhibits a significant enhancement in intensity over the optically thin value. To our knowledge, this is the first time that such an enhancement has been detected on such a sound statistical ...
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
This study describes the construction of a simple mathematical model its validation through the simulation in transient state of a real cycle performed by a solar refrigerator based on physical adsorption using an activated carbon/methanol pair. The deviation from experimental results was 4% for the cycled mass of methanol, 2.2 % for maximum collector average temperature, and 3 x 10{sup -3} for the theoretical cycle coefficient of performance. Additional simulations of the same cycle inputting values representing different types and larger amounts of activated carbon showed the possibility of increasing the cycled methanol mass up to about 150%. (author) 26 refs., 16 figs., 9 tabs.
1993-12-31
Influence of solar activity and environment on 10Be in recent natural archives
Energy Technology Data Exchange (ETDEWEB)
Understanding the link between the Sun and climate is vital in the current incidence of global climate change, and 10Be in natural archives constitutes an excellent tracer for this purpose. As cosmic rays enter the atmosphere, cosmogenic isotopes like 10Be and 14C are formed. Variations in solar activity modulate the amount of incoming cosmic rays, and thereby cosmogenic isotope production. Atmospherically produced 10Be enters natural archives such as sediments and glaciers by wet and dry deposition within about a year of production. 10Be from natural archives therefore provides information on past solar activity, and because these archives also contain climate information, solar activity and climate can be linked. One remaining question is to what degree 10Be in natural archives reflects production, and to what extent the local and regional environment ...
2009-05-15
Development of GaInAsP for GaInAsP/Ge cascade solar cells
Energy Technology Data Exchange (ETDEWEB)
Quaternary semiconductor compounds are ideal candidates for use in monolithic cascade solar cells because the lattice constant and the bandgap of such compounds can be independently varied. The quaternary semiconductor compound Ga[sub 0.83]In[sub 0.17]As[sub 0.67]P[sub 0.33] not only is lattice matched to GaAs and Ge but also provides a current matched top cell for the GaInAsP/Ge monolithic cascade solar cell. Under concentration of 100 suns, the projected efficiency for such a cell is about 34%. The growth of Ga[sub 0.83]In[sub 0.17]As[sub 0.67]P[sub 0.33] lattice matched to GaAs and Ge has been demonstrated. GaInAsP solar cells have been grown on both GaAs and Ge substrates. A GaInAsP on GaAs solar cell with an active area efficiency of 23.2% for 1 sun, AM 1.5 direct illumination has been prepared. A proposed structure for the GaInAsP/Ge cascade cell is also given.
1992-12-01
Changes in Sea-Level Pressure over South Korea Associated with High-Speed Solar Wind Events
We explore a possibility that the daily sea-level pressure (SLP) over South Korea responds to the high-speed solar wind event. This is of interest in two aspects: First, if there is a statistical association this can be another piece of evidence showing that various meteorological observables indeed respond to variations in the interplanetary environment. Second, this can be a very crucial observational constraint since most models proposed so far are expected to preferentially work in higher latitude regions than the low latitude region studied here. We have examined daily solar wind speed ${\\rm V}$, daily SLP difference ${\\rm \\Delta SLP}$, and daily ${\\rm \\log(BV^{2})}$ using the superposed epoch analysis in which the key date is set such that the daily solar wind speed exceeds 800 ${\\rm kms^{-1}}$. We find that the daily ${\\rm \\Delta SLP}$ averaged out of 12 events ...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
In this paper, we study the optical properties of indium sulfide thin films to establish the best conditions to obtain a good solar cell buffer layer. The In2S3 buffer layers have been prepared by chemical bath deposition (CBD) and thermal evaporation (PVD). Optical behavior differences have been found between CBD and PVD In2S3 thin films that have been explained as due to structural, morphological and compositional differences observed in the films prepared by both methods. The resultant refractive index difference has to be attributed to the lower density of the CBD films, which can be related to the presence of oxygen. Its higher refractive index makes PVD film better suited to reduce overall reflectance in a typical CIGS solar cell.
2008-01-01
British Library Electronic Table of Contents (United Kingdom)
PurposeTo characterize the morphology of outer retinal holes caused by solar maculopathy, using spectral-domain optical coherence tomography (SD-OCT). DesignThis study is an observational case series. MethodsThe SD-OCT findings of 3 patients (6 eyes) with chronic solar maculopathy are presented. ResultsSD-OCT demonstrates a characteristic appearance of partial-thickness hole(s) in the outer retina at the fovea. In 3 of 6 eyes, there is 1 hole directly beneath the umbo. In the remaining 3 eyes, there are multifocal holes spread across the fovea. Holes in more restricted layers, as had been previously reported with time-domain OCT, were not seen. In addition, advanced visualization of SD-OCT data demonstrates a hyperreflective ring around the outer retinal hole. ConclusionsSD-OCT can be used...
2011-01-01
...Observatory Edinburgh SkyView Virtual Observatory Solar System Simulator Space Telescope Science Institute Space Weather : A Research Perspective Subaru Telescope Project Two Micron All ...Universities for Research in Astronomy Subjects: space observation DeweyClass: 522 Resource type: index Space Weather : A Research Perspective Documents discussing space weather , the ...elements of near-Earth space, Earth-space meteorology and practical consequences of space weather . Glossary included. Author: National Academy of ...
British Library Electronic Table of Contents (United Kingdom)
The antimicrobial activity of simulated solar disinfection (SODIS) in the presence and absence of riboflavin against various protozoa and helminth organisms was investigated in this study. Assays were conducted in transparent 12 well microtitre plates containing a suspension of test organisms in the presence or absence of 250mM riboflavin. Plates were exposed to simulated sunlight at an optical irradiance of 550Wm^-^2 (watts per square metre) delivered from a SUNTEST(TM) CPS+ solar simulator. Aliquots of the test suspensions were taken at set time points and the viability of the test organisms was determined by either culture, microscopy or flow cytometry where applicable. With Acanthamoeba, Naegleria, Entamoeba and Giardia exposure to SODIS at an optical irradiance of 550Wm^-^2 for up to ...
2011-01-01
Status of research on convective losses from solar central receivers
Energy Technology Data Exchange (ETDEWEB)
Progress in the worldwide capability of predicting the convective energy loss from solar central receivers is reviewed. The significant advances in the past three years have been in experimental areas. Baseline measurements of the convective heat transfer from large high-temperature surfaces, e.g., a flat plate and a cubical cavity, have been completed and empirical correlations have been obtained. Theoretical modeling activities have not kept pace with the experimental advances, however. Currently, the primary theoretical emphasis is the development and testing of turbulence models suitable for buoyant flows. Three major needs have been identified: the measurement of convective energy losses from operating solar central receivers; the continued development of theoretical models in spite of the relatively slow progress to date; and the quantification of the effects of atmospheric turbulence.
1983-06-01
III-phosphides heterojunction solar cell interface properties from admittance spectroscopy
International Nuclear Information System (INIS)
GaInP solar cell interfaces were characterized by admittance spectroscopy. Admittance spectroscopy is shown to be sensitive to the band structure at the heterojunction interfaces. In particular, a correlation between activation energy of the capacitance step in a capacitance versus temperature plot and effective potential barrier for majority carriers is demonstrated, indicating a new method for the determination of potential barriers at heterointerfaces. Using this technique, the effective potential barrier for holes at the p-Al_0_._5_3In_0_._4_7P/p-GaAs interface is found to be equal to 0.6 eV. Effects of interface defects and spreading resistance in the emitter of solar cells are illustrated and discussed.
2009-08-21
Dynamics of photosynthetic photon flux density (PPFD) and estimates in coastal northern California
British Library Electronic Table of Contents (United Kingdom)
Plants require solar radiation for photosynthesis and their growth is directly related to the amount received, assuming that other environmental parameters are not limiting. Therefore, precise estimation of photosynthetically active radiation (PAR) is necessary to enhance overall accuracies of plant growth models. This study aimed to explore the PAR radiant flux in the San Francisco Bay Area of northern California. During the growing season (March through August) for 2?years 2007?2008, the on-site magnitudes of photosynthetic photon flux densities (PPFD) were investigated and then processed at both the hourly and daily time scales. Combined with global solar radiation (R S) and simulated extraterrestrial solar radiation, five PAR-related values were developed, i.e., flux density-based PAR ...
2011-01-01
A model for Schottky-barrier solar cell analysis
A general model for the analysis of metal-semiconductor solar cells is presented. The model takes into account the cell optical properties, carrier recombination effects, semiconductor minority-carrier properties, series resistance, cell thickness, and active surface area. Numerical methods are used to solve the appropriate continuity equations and hence compute the photocurrent density under AMO conditions. The operation of the model is demonstrated using p- and n-type Si and GaAs with Au being taken as the barrier metal. Calculations are presented showing the effect on solar energy conversion efficiency of surface recombination velocity, barrier height, minority-carrier lifetime, barrier metal thickness, collecting grid configuration, and cell thickness. A comparison of practical and computed data for the Au/n-GaAs system yields good agreement. (AIP)
1976-05-01
Investigations on solar grade silicon and process engineering of advanced silicon solar cells
Energy Technology Data Exchange (ETDEWEB)
This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference ...
2007-07-01
Development of the EE-1 small community solar thermal power system
The development status of the EE-1 Small Community Solar Thermal Power Experiment (SCSE Program) is presented. Current activities on the Phase II single module development effort are presented, together with plans for a Phase III 1 MW/sub e/ demonstration plant. A description of the various subsystems and components is given with a brief review of their development background. Latest performance figures are given for a 1 MW/sub e/ plant, based on 56 power modules, each consisting of a 12m parabolic dish concentrator, a cavity receiver, an organic Rankine power conversion subsystem and a ground-mounted solid-state rectifier.
1981-01-01
Paul Scherrer Institut Scientific Report 2001. Volume V: General Energy
Energy Technology Data Exchange (ETDEWEB)
Major advances in 'Energy and Materials Cycles' have been achieved in the removal of heavy metals from the solid residues of municipal waste incineration. It has been conclusively shown that the oxidation/reduction conditions established during the thermal treatment of filter ash have a decisive influence on the evaporation of groups of heavy metals. With respect to biomass gasification, studies have been carried out with respect to the best way of extracting pure hydrogen from the low calorific value gas that is typically obtained from a biomass gasifier. The overarching goal of the laboratory 'High Temperature Solar Technology' is the use of solar energy for the production of solar fuels, or for the reduction of CO{sub 2} emissions in large scale industrial processes that are conventionally carried out with the use of fossil fuels. In a short-term project targeted at the ...
2002-03-01
ROSAT observations of the RSCVn binary sigma Geminorum
DEFF Research Database (Denmark)
X-ray observations of the RSCVn system sigma Geminorum have been undertaken with the ROSAT observatory. Several spectra of very good signal-to-noise ratio were obtained. Spectral fitting using metal abundances amounting to 50% of solar values reveal two temperature components at 2 MK and 12 MK. Previous EXOSAT observations showed another component at 40 MK. Particular interest is focused on the temporal variations of the X-ray emission. It is found that variations occur on time scales ranging from years to hours and minutes.
1997-01-01
Design and performance of the solar-powered floor heating system in a green building
Energy Technology Data Exchange (ETDEWEB)
In the green building of Shanghai Research Institute of Building Science, the evacuated tubular solar collectors with a total area of 150 m{sup 2} were installed to provide heating for the covered area of 460 m{sup 2}. The floor heating coil pipes were made of high-quality pure copper with the dimension of {phi} 12 x 0.7 mm. Under typical weather condition of Shanghai, the average heating capacity was 25.04 kW during the working hours from 9:00 to 17:00, which was sufficient to keep indoor thermal environment. The average electric COP of the floor heating system was 19.76 during the system operation. Compared with the widely used air-source heat pump heating systems with the electric COP of 3.5 in Shanghai, the solar-powered floor heating system shows great potential in energy conservation in winter. With respect to the whole heating period, the solar fraction was 56%. According to the performance analysis of the system ...
2009-07-15
Pacific decadal oscillation hindcasts relevant to near-term climate prediction
Decadal-scale climate variations over the Pacific Ocean and its surroundings are strongly related to the so-called Pacific decadal oscillation (PDO) which is coherent with wintertime climate over North America and Asian monsoon, and have important impacts on marine ecosystems and fisheries. In a near-term climate prediction covering the period up to 2030, we require knowledge of the future state of internal variations in the climate system such as the PDO as well as the global warming signal. We perform sets of ensemble hindcast and forecast experiments using a coupled atmosphere-ocean climate model to examine the predictability of internal variations on decadal timescales, in addition to the response to external forcing due to changes in concentrations of greenhouse gases and aerosols, volcanic activity, and solar cycle variations. Our results highlight that an initialization of the upper-ocean state using historical ...
2010-01-01
DEFF Research Database (Denmark)
Oscillating stars in binary systems are among the most interesting stellar laboratories, as these can provide information on the stellar parameters and stellar internal structures. Here we present a red giant with solar-like oscillations in an eclipsing binary observed with the NASA Kepler satellite. We compute stellar parameters of the red giant from spectra and the asteroseismic mass and radius from the oscillations. Although only one eclipse has been observed so far, we can already determine that the secondary is a main-sequence F star in an eccentric orbit with a semi-major axis larger than 0.5 AU and orbital period longer than 75 days.
2010-01-01
Thin film solar cells and solar cell testing - photovoltaic cells, radiation damage to cadmium sulfide solar cells, and airplane testing of solar cells
1964-01-01
Why the sunspot cycle is double peaked
Many sunspot cycles are double peaked. In 1967 Gnevyshev suggested that actually all cycles have two peaks generated by different physical mechanisms, but sometimes the gap between them is too short for the maxima to be distinguished in indices of the total sunspot activity. Here we show that indeed all cycles have two peaks easily identified in sunspot activity in different latitudinal bands. We study the double peaks in the last 12 sunspot cycles and show that they are manifestation of the two surges of toroidal field - the one generated from the poloidal field advected all the way on the surface to the poles, down to the tachocline and equatorward to sunspot latitudes, and another one generated from the poloidal field diffused at midlatitudes from the surface to the tachocline and transformed there into toroidal field. The existence of these two surges of toroidal field is due to the relative magnitudes of the speed of the large-scale ...
2011-01-01
Is there an enhancement of muons at sea level from transient events?
In a recent study of a search for enhancements from the galactic center with muons at sea level using the TUPI muon telescope, we have found several ground level enhancements (GLEs) as very sharp peaks above the count rate background. This paper reports a consistent analysis of two GLEs observed in December 2003 and detected after an up-grade of the data acquisition system, which includes a noise filter and which allows us to verify that the GLEs are not mere background fluctuations. The main target of this study is a search for the origin of the GLEs. The results show that one of them has a strong correlation with a solar flare, while the other has an unknown origin, because there is neither a satellite report of a solar flare, nor prompt X-ray emission, and nor a excess of nuclei during the raster scan where the GLE was observed. Even so, two possibilities are analyzed: the solar ...
2004-01-01
One of the most interesting discoveries of the X-ray Telescope and EUV Imaging Spectrometer (EIS) on board the Hinode solar observatory is the presence of persistent high temperature high speed outflows from the edges of active regions. Measurements by EIS indicate that the outflows reach velocities of 50 km/s with spectral line asymmetries approaching 200 km/s. It has been suggested that these outflows may lie on open field lines that connect to the heliosphere, and that they could potentially be a significant source of the slow speed solar wind. A direct link has been difficult to establish, however. In this letter, we use EIS measurements of spectral line intensities that are sensitive to changes in the relative abundance of Si and S as a result of the first ionization potential (FIP) effect, to measure the chemical composition in the outflow regions of AR 10978 over a period of 5 days in December 2007. We find that Si ...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
A review of theoretical and observational research on the magnetopause during 1987-1990. Starting with recent work on magnetic reconnection, the review proceeds to magnetopause surface wave phenomena, including the controversy over the role of solar wind pressure pulses in the coupling process and in the mimicking of flux transfer events signatures, and finishes with the magnetopause structure and associated wave phenomena. Recent advances in computer modeling of the magnetopause and the pertinent processes are also discussed. 108 refs.
1991-01-01
Rayleigh Scattering in Rare Gas Liquids
The Rayleigh scattering length has been calculated for rare-gas liquids in the ultraviolet for the frequencies at which they luminesce. The calculations are based on the measured dielectric constants in the gas phase, except in the case of xenon for which measurements are available in the liquid. The scattering length mayplace constraints on the design of some large-scale detectors, using uv luminescence, being proposed to observe solar neutrinos and dark matter. Rayleigh scattering in mixtures of rare-gas mixtures is also discussed.
2002-01-01
Energy Technology Data Exchange (ETDEWEB)
The observed strength of the carbon dioxide absorption bands recorded on spectrobolograms of the transparency of the earth's atmosphere between wavelengths 300 and 2500 nanometers as part of the Smithsonian Solar Constant Program were used to extract the abundance of carbon dioxide in the atmosphere. The details of the analysis and the sources of error are discussed. 11 references, 5 figures, 1 table. (ACR)
1983-11-01
Evolution of a horizontal branch Population II star with total mass 0.63 Msub solar
The theoretical evolution of a horizontal branch star of Population II is followed through the helium burning in the core phase and is compared with the results given by other investigators. The m- fluence of different physics and interpolation schemes in the opacity tables is discussed. Some thoughts are given on the explanation of the erratic period variations observed in some of the RR Lyrae variables in the globular clusters. (auth)
1973-01-01
CORONAL OBSERVATIONS OF CMEs Report of Working Group A
imaging of the solar corona began in 1960 via a primitive pinhole camera on a ... IR wavelengths. Such data help us to study in detail the pre-eruptive ...... Schematic picture of flare loops, CME, and the current sheet between ..... As part of NASA's Living With a Star (LWS) program the planned Sentinel mission ...
Experimental and theoretical studies of solar steam reforming assisted by molten salts
Energy Technology Data Exchange (ETDEWEB)
The pathway to hydrogen generation entirely from renewable energy and material sources probably goes by a transitional period with the utilization of hybrid fossil/renewable integrated systems. Solar steam reforming of methane is set in this context, specifically suited for a country like Italy whose actual energy policy is mainly based on the imported NG, but also characterized by convenient solar radiation levels in the Southern Regions. A new solar SMR process is being developed by ENEA, using molten nitrates as solar heat carriers and storage medium at about 550 C. The potential of this process have been proved theoretically by process simulation studies. Engineering and experimental activities aimed to the development of a prototype apparatus are now in progress in ENEA's laboratories. It is remarkable that the developed technology (MS powered SMR) can find interesting ...
2010-07-01
International Nuclear Information System (INIS)
This short article describes the strategies taken into consideration by the Swiss Federal Office of Energy for the promotion of renewable forms of energy in Switzerland. Two basic models are considered and the parts to be played by the Swiss Confederation, the Swiss Cantons, Energy Agencies and professional organisations are discussed. The importance of the activities of partner organisations and actor-networks in various areas such as solar, small hydro, geothermal and wind energy are discussed, as are models for financing the necessary promotion and marketing efforts
International Nuclear Information System (INIS)
CEA is a public body devoted to technological research with 9 research centers throughout France. The activities of its 16,000 scientists, engineers, and technicians deal with new technologies for nuclear energy and alternative energies (fuel batteries, solar energy, energy storage) as well as technologies related to the new economy, in particular in the fields of microelectronics, bio-technologies, and materials. (author)
2000-10-01
The rate-limiting mechanism of transition metal gettering in multicrystalline silicon
Energy Technology Data Exchange (ETDEWEB)
Multicrystalline silicon is a very interesting material for terrestrial solar cells. Its low cost and respectable energy conversion efficiency (12-15%) makes it arguably the most cost competitive material for large-volume solar power generation. However, the solar cell efficiency of this material is severely degraded by regions of high minority carrier recombination which have been shown to possess both dislocations and microdefects. These structural defects are known to increase in recombination activity with transition metal decoration. Therefore, gettering of metal impurities from the material would be expected to greatly enhance solar cell performance. Contrary to this rationale, experiments using frontside phosphorus and/or backside aluminum treatments have been found to improve regions with low recombination activity while having little or no effect on the ...
1997-04-01
Electrochemical Solar Energy Converter
International Science & Technology Center (ISTC)
Elaboration of Electrochemical Solar Energy Converter Incorporating Cadmium Selenide Semiconductor Developed Electrochemically
Energy Technology Data Exchange (ETDEWEB)
Described herein are the results of the FY1994 research program for structural defects of silicon-based amorphous materials for solar cells. The study on light generation defects of the a-Si:H system and rejuvenation process by annealing establishes the effects of light irradiation time on changed neutral dangling bond density as a result of light irradiation at varying temperature of 77K, room temperature and 393K. The study on annealing to rejuvenate light generation defects of various types of a-Si-H systems establishes the activation energy distribution with respect to annealing to remove light-induced defects, showing that hydrogen affects the distribution of light-induced defects. The study on decaying process of light-induced ESR for undoped and N-doped a-Si:H systems observes the decaying process of light-induced ESR, after light is cut off, extending for a period of several seconds to several hours at 77K for the ...
1994-12-01
DOE education and training grant. Final report
Energy Technology Data Exchange (ETDEWEB)
The work reported included workshop-style, hands-on training sessions to reach three hundred residents of the Detroit area. The training was for teaching low-cost weatherization applications; teaching/constructing/installing thermal shades; and teaching/constructing/installing vertical wall solar air panels. All activities under the grant are summarized, including number and type of workshops, number of participants trained, etc. The organizations which actively supported and contributed to the program are identified, and the program's efforts and accomplishments are evaluated. (LEW)
1982-01-01
The Galactic Exoplanet Survey Telescope (GEST)
The Galactic Exoplanet Survey Telescope (GEST) will observe a 2 square degree field in the Galactic bulge to search for extra-solar planets using a gravitational lensing technique. This gravitational lensing technique is the only method employing currently available technology that can detect Earth-mass planets at high signal-to-noise, and can measure the frequency of terrestrial planets as a function of Galactic position. GEST's sensitivity extends down to the mass of Mars, and it can detect hundreds of terrestrial planets with semi-major axes ranging from 0.7 AU to infinity. GEST will be the first truly comprehensive survey of the Galaxy for planets like those in our own Solar System.
2002-01-01
Energy Technology Data Exchange (ETDEWEB)
The primary aims of the BESS-Polar program are precise measurements of the low-energy antiproton spectrum and search for cosmologically significant antimatter, which would provide new clues to understand the early Universe. The second flight (BESS-Polar II) over Antarctica was successfully carried out in December 2007 - January 2008. We performed 24.5 days scientific observation just at the solar minimum. The payload worked well during the flight and 4.7 billion cosmic-ray events were collected, which corresponds to 10-20 times statistics of the BESS data taken in the previous solar minimum period (1995 and 1997). Based on the BESS-Polar II data, we will present recent preliminary results of cosmic-ray antiproton measurements and sensitive search for antimatter. (authors)
2010-07-01
On the radial distribution of gamma rays in the outer galaxy
International Nuclear Information System (INIS)
The authors describe a new method which makes it possible to determine the radial distribution of the diffuse component of galactic gamma rays outside the solar circle. They use the observation that a good correlation exists between gamma-ray intensities and total column densities of the local interstellar gas and that the fractional column density of H_2<0.1 HI outside the solar circle. Thus the gamma-ray intensities are shown to be proportional to N(HI). The authors use the kinematics of the HI to determine the distances from which various fractions of the emission originate in the second and third galactic quadrants. Preliminary results of our analysis show that a significant flux of gamma rays originates from distances as large as 18 kpc from the galactic centre. (Auth.).
1982-08-04
Characterization of polymer solar cells by TOF-SIMS depth profiling
Energy Technology Data Exchange (ETDEWEB)
Solar cells consisting of polymer layers sandwiched between a transparent electrode on glass and a metal top electrode are studied using dynamic time-of-flight secondary ion mass spectrometry (TOF-SIMS) in dual-beam mode. Because depth profiling of polymers and polymer-metal stacks is a relatively new field the craters were thoroughly investigated by environmental SEM (ESEM), interferometry, surface profilometry and tapping mode AFM. A huge increase in crater bottom roughness was observed when starting from the aluminum top layer going in depth, resulting in a loss of depth resolution. It is shown that layer-to-layer diffusion and contaminants at buried interfaces can be extracted from the depth profiles when taking into account the loss of depth resolution.
2003-01-15
Energy Technology Data Exchange (ETDEWEB)
Two window layer materials, Al{sub 0.51}In{sub 0.49}P (E{sub g} = 2.3 eV) and Ga{sub 0.51}In{sub 0.49}P (E{sub g} = 1.88 eV) were compared for gas-source and solid-source MBE grown GaAs and Ga{sub 0.84}In{sub 0.16}As{sub 0.68}P{sub 0.32} (E{sub g} = 1.55 eV) solar cells. Due to the wider band-gap of Al{sub 0.51}In{sub 0.49}P, the increased spectral response was observed for both GaAs and Ga{sub 0.84}In{sub 0.16}As{sub 0.68}P{sub 0.32} material based solar cells. In the case of the GaAs cells, the short-circuit current density was observed to increase from 32.5 mA/cm{sup 2} to 34.4 mA/cm{sup 2} with the Al{sub 0.51}In{sub 0.49}P window layer at AM0. Similar improvement was observed for the Ga{sub 0.84}In{sub 0.16}As{sub 0.68}P{sub 0.32} solar cells.
1997-12-31
Polymer-metal complex as gel electrolyte for quasi-solid-state dye-sensitized solar cells
International Nuclear Information System (INIS)
A kind of polymer-metal complex gel electrolyte is successfully prepared and is used in dye-sensitized solar cells. Raman and X-ray photoelectron spectroscopy confirm the structure of this complex and is found that the metal ion reacts with nitrogen in the polymer. This novel electrolyte shows apparent diffusion coefficient of iodide of 8.37 x 10-7 cm2 s-1 and the energy conversion efficiency of 6.10% when the amount of ZnI2 is 0.04 M. By studying the dissociation active energy of the inorganic salt in electrolytes, we find that the metal salts can dissociate more easily after reacting with polymer and as a result can provide extra free iodide ion. The cell maintains ca. 93% of its initial efficiency after 20 d without further sealing, which shows good long-time stability.
2011-01-01
High concentration low wattage solar arrays and their applications
Energy Technology Data Exchange (ETDEWEB)
Midway Labs currently produces a 335x concentrator module that has reached as high as 19{percent} active area efficiency in production. The current production module uses the single crystal silicon back contact SunPower cell. The National Renewable Energy Lab has developed a multi junction cell using GalnP/GaAs technologies. The high efficiency ({gt}30{percent}) and high cell voltage offer an opportunity for Midway Labs to develop a tracking concentrator module that will provide 24 volts in the 140 to 160 watt range. This voltage and wattage range is applicable to a range of small scale water pumping applications that make up the bulk of water pumping solar panel sales. {copyright} {ital 1997 American Institute of Physics.}
1997-02-01
Magnetospheric Emissions from the Planet Orbiting tau Boo: A Multi-Epoch Search
All of the solar system gas giants produce electron cyclotron masers, driven by the solar wind impinging on their magnetospheres. Extrapolating to the planet orbiting tau Boo, various authors have predicted that it may be within the detection limits of the 4-meter wavelength (74 MHz) system on the Very Large Array. This paper reports three epochs of observations of tau Boo. In no epoch do we detect the planet; various means of determining the upper limit to the emission yield single-epoch limits ranging from 135 to 300 mJy. We develop a likelihood method for multi-epoch observations and use it to constrain various radiation properties of the planet. Assuming that the planet does radiate at our observation wavelength, its typical luminosity must be less than about 10^{16} W, unless its radiation is highly beamed into a solid angle Omega << 1 sr. While within the range of ...
2007-01-01
High-efficiency GaAs solar cells on mm and sub-mm grain-size polycrystalline Ge substrates
Energy Technology Data Exchange (ETDEWEB)
GaAs material and device structure optimization studies on optical-grade, millimeter-and-less grain-size polycrystalline Ge substrates are presented. We discuss the growth of high-quality epitaxial layers across various crystalline orientations of a polycrystalline substrate; this is important for obtaining high-performance solar cells. The GaAs solar cell on n-type poly-Ge substrate is a p-on-n type, with an undoped spacer between the p-emitter and the n-base. An experimental study of dark currents in these junctions, with and without the spacer, as a function of temperature (77K to 288K) is presented; this study suggests that the spacer reduces the tunneling contribution to dark current. In addition, we describe device-structure optimization studies that have led us to achieve an open-circuit voltage (V{sub oc}) exceeding 1 Volt and an AM1.5 efficiency of {approximately}19{percent} for a 4-cm{sup 2}-area GaAs cell on sub-mm grain-size ...
1997-02-01
One of the NASA research activities was to identify, characterize, and simulate a series of technologies that could be used for hydrogen production at NASA Kennedy Space Center (KSC) using locally available sources. This project examined the production of hydrogen from solar energy. To produce hydrogen by water splitting, the operating voltage of conventional photovoltaic (PV) cells cannot supply the overvoltage required. Thus, the objective of this project was to research and develop photoelectrochemical (PEC) cells that can supply the required voltage for water splitting by constructing a multiple bandgap tandem PV cell and a photocatalyst that can be activated by infrared (IR) photons transmitted through the PV cell. The proposed concept is different from conventional PEC water splitting by using multiple band gap combinations. The advantages for this PEC cell concept is that the PV cells are not in contact with the ...
2009-01-01
The temporal evolution of coronal loops observed by GOES-SXI
We study the temporal evolution of coronal loops using data from the Solar X-ray Imager (SXI) on board of GOES-12. This instrument allows us to follow in detail the full lifetime of coronal loops. The observed light curves suggest three somewhat distinct evolutionary phases: rise, main, and decay. The durations and characteristic timescales of these phases are much longer than a cooling time and indicate that the loop-averaged heating rate increases slowly, reaches a maintenance level, and then decreases slowly. This suggests that a single heating mechanism operates for the entire lifetime of the loop. For monolithic loops, the loop-averaged heating rate is the intrinsic energy release rate of the heating mechanism. For loops that are bundles of impulsively heated strands, it is an indication of the frequency of occurrence of individual heating events, or nanoflares. We show that the timescale of the loop-averaged heating rate is proportional ...
2006-01-01
Influence of weather on the behaviour of outdoor-wintered beef cattle in Scandinavia
British Library Electronic Table of Contents (United Kingdom)
The aim of the present investigation was to study the effect of weather and available protection on the behaviour of outdoor-wintered beef cattle (Bos taurus). A herd of 78-85 cattle head was studied during four winter months in the Southwest of Sweden. Protection was offered by coniferous forest situated on and around the 12ha pasture, which we divided into protection categories. During 240h we observed 10 cows and 10 heifers as focal animals (each 3h/month) during day time and adjusted observation times to the altitude of the sun. Close to the animals and at an unprotected spot of the pasture we measured temperature, wind speed and solar radiation and combined these variables to a single measure called Wind Chill Temperature (WCT). During observations the animals were in the forest in 12...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The article is the second part of a review dealing with latest developments in the area of solar cell technologies and application. Physical principles, design and efficiency as well as advantages and disadvantages of GaAs- and CdS-solar cells are described. Power generation solar cell systems with voltage converters, combined solar cell/solar collector systems and thermoelectric solar systems are presented in the second part of the article.
1983-04-01
Freeze protection valve and system
Energy Technology Data Exchange (ETDEWEB)
The present invention is a device for a solar heating system having a solar collector, a storage tank connected to the solar collector, a pump for circulating liquid from the tank to the solar collector, a supply of liquid at a temperature above freezing and a connection from the supply of liquid to the solar collector for replacing any liquid lost from said solar collector. The device comprises a sensor for sensing the temperature of liquid in the solar collector, and a valve for bleeding liquid from the solar collector when the sensed temperature falls below a predetermined minimum whereby cool liquid in the solar collector is automatically replaced by liquid at a temperature above freezing.
1985-12-10
Plasminogen Binding and Activation at the Surface of Helicobacter pylori CCUG 17874
UK PubMed Central (United Kingdom)
The binding of iodine-labelled plasminogen to Helicobacter pylori CCUG 17874 was characterized. Inhibition of the binding was observed after preincubation of H. pylori...Full Text Available
1998-10-01
Atmospheric chemistry in volcanic plumes
UK PubMed Central (United Kingdom)
Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to the role of chemical cycles involving halogen species and...Full Text Available
2010-04-13
Space Weather Prediction Center Education and Outreach
Education resources dealing with solar-terrestrial physics, solar effects, solar radiation, etc. Includes links to short reference papers on subjects ... ...
Solar Cell Radiation Response near the Interface of Different ...
... Solar Cell Radiation Respinnse Near the Interface o~f fliffprerv- ... 5 4. CALCUTl-ATED SOLAR CELL RLSPONSE FOR VARIOUS BASE MATERIALS ...
1971-11-01
A silicon solar cell assembly comprising a large, thin silicon solar cell bonded to a metal mount for use when there exists a mismatch in the thermal expansivities of the device and the mount.
1979-01-01
European Space Agency announces contest to "Name the Cluster Quartet"
1. Contest rules The European Space Agency (ESA) is launching a public competition to find the most suitable names for its four Cluster II space weather satellites. The quartet, which are currently known as flight models 5, 6, 7 and 8, are scheduled for launch from Baikonur Space Centre in Kazakhstan in June and July 2000. Professor Roger Bonnet, ESA Director of Science Programme, announced the competition for the first time to the European Delegations on the occasion of the Science Programme Committee (SPC) meeting held in Paris on 21-22 February 2000. The competition is open to people of all the ESA member states (*). Each entry should include a set of FOUR names (places, people, or things from history, mythology, or fiction, but NOT living persons). Contestants should also describe in a few sentences why their chosen names would be appropriate for the four Cluster II satellites. The winners will be those which are considered most suitable and relevant for the Cluster II mission. ...
2000-02-01
Cracking of Alloy 800 tubing in superheated steam in a solar receiver
Energy Technology Data Exchange (ETDEWEB)
The solar central receiver at the Barstow Pilot Plant is a once-through steam boiler consisting of vertical arrays of Alloy 800 tubes. Water/steam leaks associated with tube bends near the receiver outlet were observed after 16 service months. The leaks resulted from through-wall cracks localized in the crown of tube bends operating in the temperature range from 550 to 650/sup 0/C. Initiation occurred on the ID (steam side) of the tube and propagated transgranular through the tube wall. Cracking was axial and circumferential; in general, the circumferential cracks were more severe than the axial cracks. Thick oxide layers showed on the ID of the receiver tubes; a 25-..mu..m thick oxide layer had formed on tubing which operated at 650/sup 0/C. In addition, an enhanced oxidation layer was observed along a narrow band in the crown of the tube. This band was up to five times thicker than the oxide elsewhere in the tube. All ...
1985-10-01
International Nuclear Information System (INIS)
This paper presents case studies of economic feasibility of solar photovoltaic systems using the software AVES-F (Analysis of Economic Feasibility of Photovoltaic Systems), developed by the authors, considering cases of stand-alone and grid-connected systems. The software takes into account several factors that can influence the economic feasibility of these kind of systems, like load to be supplied, distance to the grid, the use regime of the system, applied subsidies and others. The main goal of this paper is to analyze some of these factors and to observe how they can affect the economics of PV systems for electricity generation. (authors)
2004-06-07
Computer model of high-latitude scintillation. [WBMOD program
Energy Technology Data Exchange (ETDEWEB)
The DNA Wideband satellite experiment provided extensive data on scintillation produced in high-altitude structured plasmas. A computer program, WBMOD, is being developed to summarize those data in an applications-oriented way. The program contains the phase-screen scattering theory of Rino and a morphological description of ionospheric irregularities (thus far only at auroral latitudes) based on Wideband observations. It permits a user to compute scintillation indices for both phase and intensity as a function of system operating parameters and solar-ionospheric disturbance level. Correction is made for multiple scatter, and the user may choose either one-way (communication) or two-way (radar) propagation.
1982-01-01
Computer model of high-latitude scintillation
International Nuclear Information System (INIS)
The DNA Wideband satellite experiment provided extensive data on scintillation produced in high-altitude structured plasmas. A computer program, WBMOD, is being developed to summarize those data in an applications-oriented way. The program contains the phase-screen scattering theory of Rino and a morphological description of ionospheric irregularities (thus far only at auroral latitudes) based on Wideband observations. It permits a user to compute scintillation indices for both phase and intensity as a function of system operating parameters and solar-ionospheric disturbance level. Correction is made for multiple scatter, and the user may choose either one-way (communication) or two-way (radar) propagation.
Ultraviolet radiation in Finland
Energy Technology Data Exchange (ETDEWEB)
Solar ultraviolet radiation is damaging for living organisms due to its high energy pro each photon. The UV radiation is often separated into three regions according to the wavelength: UVC (200-280 nm), UVB (280-320 nm) and UVA (320-400 nm). The most hazardous part, UVC is absorbed completely in the upper atmosphere by molecular oxygen. UVB radiation is absorbed by atmospheric ozone partly, and it is reaching Earth`s surface, as UVA radiation. Besides atmospheric ozone, very important factors in determining the intensity of UVB radiation globally are the solar zenith angle and cloudiness. It may be calculated from global ozone changes that the clear-sky UVB doses may have enhanced by 10-15 % during spring and 5-10 % during summer at the latitudes of Finland, following the decrease of total ozone between 1979-90. The Finnish ozone and UV monitoring activities have become a part of international ...
1996-12-31
We prepared submicron-scale spherical hollow particles of anatase TiO2 by using a polystyrene-bead template. The obtained particles were very uniform in size, with a diameter of 490 nm and a shell thickness of 30 nm. The Brunauer-Emmett-Teller surface area measurements revealed a large value of 70 m2/g. The photocatalytic property was investigated by the complete decomposition of gaseous isopropyl alcohol under UV irradiation. It was indicated that the activity of the hollow spheres was 1.8 times higher than that of the conventional P25 TiO2 nanoparticles with a diameter of 30 nm. Furthermore, we fabricated a dye-sensitized solar cell (DSC) using an electrode of the TiO2 hollow spheres, and examined the photovoltaic performance under simulated sunlight. Although the per-area efficiency was rather low (1.26%) because of a low area density of TiO2 on the electrode, the per-weight efficiency was 2.5 times higher than those of the conventional DSCs ...
2007-12-19
We review X-ray plasma diagnostics based on the line ratios of He-like ions. Triplet/singlet line intensities can be used to determine electronic temperature and density, and were first developed for the study of the solar corona. Since the launches of the X-ray satellites Chandra and XMM-Newton, these diagnostics have been extended and used (from CV to Si XIII) for a wide variety of astrophysical plasmas such as stellar coronae, supernova remnants, solar system objects, active galactic nuclei, and X-ray binaries. Moreover, the intensities of He-like ions can be used to determine the ionization process(es) at work, as well as the distance between the X-ray plasma and the UV emission source for example in hot stars. In the near future thanks to the next generation of X-ray satellites (e.g., Astro-H and IXO), higher-Z He-like lines (e.g., iron) will be resolved, allowing plasmas with higher temperatures and densities to be ...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The moment analysis of pulse responses was applied to a biological activated carbon (BAC) bed to evaluate the microbial activity. Glucose and activated carbon fiber (ACF) were employed in experiments as a model tracer and an activated carbon respectively. No significant difference in biodegradation rates of glucose by microorganisms attached on different solid supports such as activated carbon inactivated carbon and glass fibers was observed. However, higher microbial activity was obtained from microorganisms supported on the ACF in terms of the apparent degradation of total organic including metabolic byproducts by microorganisms, since part of the metabolic byproducts was irreversibly deposited onto the ACF. 11 refs., 6 figs.
1996-07-10
Energy Technology Data Exchange (ETDEWEB)
The article describes the Solair 1 solar cell-powered aircraft. Measures to reduce the weight of the craft are cited.
1983-03-01
A NEW FORM OF SOLID STATE SOLAR GENERATOR
... nent to the design and construction of metal-semiconductor solar cells, in that both the photovoltage and the efficiency of metal-semiconductor cells ...
1962-01-01
Space activities in the Bolivarian Republic of Venezuela
British Library Electronic Table of Contents (United Kingdom)
This paper summarizes the establishment and current development of space activities in the Bolivarian Republic of Venezuela. Space activities in Venezuela are focused on the areas of telecommunications, Earth observation and research on the physical properties of the Earth, and have as a primary goal the satisfaction of social needs. Current development of space activities started in 1999 when the new National Constitution recognized the value of outer space as the common heritage of mankind, and the key role of science and technology in promoting human welfare. The Bolivarian Agency for Space Activities (ABAE) was created in 2007. Its legal framework recognizes three key elements that drive its policy: the participation of society, capacity building and human training, and international c...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The effect of various window layers for InP solar cells are studied. Window materials that have type 1 and type 2 alignment in the window/emitter interface are compared. All window materials that form a type 2 alignment with InP, such as Al{sub 0.20}In{sub 0.80}P, Ga{sub 0.20}In{sub 0.80}P, Al{sub 0.55}In{sub 0.45}As and Al{sub 0.60}In{sub 0.40}P, cause a high interface recombination velocity, which deteriorates the carrier collection. This recombination takes place due to the spatially indirect quantum well transition between the triangular quantum wells formed in the interface. ZnSe as a window layer material with type 1 alignment does not have this problem, but still decreased response in the short wavelength region is observed due to misfit dislocation induced trap sites. Future prospects for the window layer development for InP are discussed. The discussion is extended also to other III-V semiconductor based solar cell ...
1994-12-31
Ionospheric response to the phenomena occurring below and above it: a summary
Energy Technology Data Exchange (ETDEWEB)
Some of well known F{sub 2} layer anomalies might have their origin in lower atmosphere and some have extra terrestrial sources. It has been suggested that the phenomena occurring below the ionosphere such as thunderstorms, lightning/sprites, volcanic eruptions and earthquakes and above the phenomena like corona mass ejection, solar flares and extra terrestrial events may produce F{sub 2} layer signatures. In the present paper we have tried to summarize the effect of some phenomena occurring below the ionosphere like thunderstorms, lightning/sprites and seismic activity and the phenomena such as solar flares which occur above the ionosphere, on the ionospheric electron and ion temperatures. The paper also discusses possibilities. The ionospheric electron and ion temperatures were measured by the RrPAa payload aboard the Iindian SRrOSS-C2 satellite. The normal day's ion and electron temperatures have been compared ...
2009-01-15
Power Tower Technology Roadmap and cost reduction plan.
Energy Technology Data Exchange (ETDEWEB)
Concentrating solar power (CSP) technologies continue to mature and are being deployed worldwide. Power towers will likely play an essential role in the future development of CSP due to their potential to provide dispatchable solar electricity at a low cost. This Power Tower Technology Roadmap has been developed by the U.S. Department of Energy (DOE) to describe the current technology, the improvement opportunities that exist for the technology, and the specific activities needed to reach the DOE programmatic target of providing competitively-priced electricity in the intermediate and baseload power markets by 2020. As a first step in developing this roadmap, a Power Tower Roadmap Workshop that included the tower industry, national laboratories, and DOE was held in March 2010. A number of technology improvement opportunities (TIOs) were identified at this workshop and separated into four categories associated with power ...
2011-04-01
PWR FISSION PRODUCT ACTIVITY LEVELS
Recent radiochemical investigations of the PWR reactor coolant have corfirmed earlier observations that the level of activities of 33 m Cs/sup 138/, 2.8 hr Kr , and 8.1 day 1/sup 131/ are more than ten times higher than those predicted for the estimated U contamination of the Zircaloy cladding. The present fission product activity levels have not, as yet, presented any problems in the PWR. (W.L.H.)
1958-05-01
Oxygen-induced enhancement of the adsorptive capacity of activated charcoal
Energy Technology Data Exchange (ETDEWEB)
Adsorption isotherms for phenol and o-cresol on activated charcoal at neutral pH and several dissolved oxygen concentrations were conducted at 23{degree}C. Significant improvements in capacities were observed with increasing dissolved oxygen concentrations for the two adsorbates. These statistically-significant additional capacities were not due to biological activities but merely due to surface chemical reactions. The improvement in capacity was directly related to the amount of oxygen per unit mass of GAC.
1992-02-01
Direct gamma-spectrometry of surface activity with IGC-30 HPGe detector
International Nuclear Information System (INIS)
The IGC-30 HPGe detector with MCA 'CANBERRA-10 PLUS' allows to determine surface contamination of areas of any type with a minimum error in radius 8-10 m, at a 'uniform' contamination. A modification of the CANBERRA hardware and software is described allowing determination of both the activity of a possible 'radioactive spot' and the activity of the whole observed surface. (author).
1993-12-02
Coir fibre toxicity: in vivo and in vitro studies.
The biological activity of coir fibre, coir ash and their components were investigated in vitro by measuring the haemolytic activity and macrophage cytotoxicity. In vivo studies carried out by injecting guinea pigs intratracheally with coir fibres resulted in resolving granulomas. The observed haemolytic activity and macrophage cytotoxicity was more marked with coir ash compared with coir fibres. Chemical analysis of coir ash revealed the presence of toxic chemical constituents in appreciable amounts. PMID:6283694
1982-03-01
The low-frequency spectral behavior of cosmic ray intensity
Energy Technology Data Exchange (ETDEWEB)
Power spectral analysis of cosmic ray intensity recorded by neutron monitors at Calgary and Deep River, Alberta, was carried out over a wide range of frequencies from 3 {times} 10{sup {minus}9} Hz to 6 {times} 10{sup {minus}6} Hz during the epoch 1965-1989 and revealed different behavior of the power spectral density for the three ranges of frequency domains. At low frequencies corresponding to the periodicity T {approx} 20 months the power spectrum shows an abrupt change in the level and profile of power spectral density (PSD). This indicates that the processes responsible for the long period variations are different from the one which causes short-period variations. At middle frequencies corresponding to periodicities between 6 and 18 months, the PSD indicates that the periodicities are not stable and show a transient character over the entire epochy of analysis. The PSD for periods T {approx} 27 days indicates an 11 year recurring tendency related to solar ...
1991-09-01
Theoretical study of indoline dyes for dye-sensitized solar cells
International Nuclear Information System (INIS)
Indoline dye sensitizers were designed and studied theoretically to increase molar extinction coefficients in the visible to near infrared region for solar-cell devices. To gain insight into dye sensitizers' structural, electronic, and optical properties, DFT/TDDFT calculations were performed on a series of dye sensitizers derived from the D149. The good agreement between the experimental and TDDFT calculated absorption spectra of the D149 sensitizer allowed us to provide a detailed assessment of the main spectral features of a series of dye sensitizers. Increase in the conjugation length resulted in a more red-shifted spectral response and less positive oxidation potential than that of the D149. The dye with the dimethylfluorene group showed stronger absorption bands due to a large dipole moment. The calculated dipoles for the dye series correlate well with the observed strong absorption bands of the electronic spectra. These results provided ...
2010-09-01
We analytically work out the orbital effects caused by a Rindlertype extra-acceleration ARin which naturally arises in some recent models of modified gravity at large distances. In particular, we focus on the perturbations induced by it on the two-body range {\\rho} and range-rate {\\rho}\\cdot which are commonly used in satellite and planetary investigations as primary observable quantities. The constraints obtained for ARin by comparing our calculations with the currently available range and range-rate residuals for some of the major bodies of the solar system, obtained without explicitly modeling ARin, are 1 - 2 \\times 10-13 m s-2 (Mercury and Venus), 1 \\times 10-14 m s-2 (Saturn), 1 \\times 10-15 m s-2 (Mars), while for a terrestrial Rindler acceleration we have 5 \\times 10-16 m s-2 (Moon). Another approach which could be followed consists of taking into account ARin in re-processing all the available data sets with accordingly modified ...
2010-01-01
Diurnal anisotropy of cosmic rays and the heliospheric transport parameters
Energy Technology Data Exchange (ETDEWEB)
We review the data on long-term changes in the solar diurnal variation of cosmic rays, observed at Deep River with a neutron monitor and at Embudo with an underground muon telescope, during the period 1965-1976. We show that the model proposed by Erdos and Kota (1979, Sixteenth ICCR, Kyoto. Conference Papers 4, 45). cannot explain the systematic changes seen in our data during 1971-1976. An insight gained from the diffusion-convection model enables us to obtain a unique solution for K parallel to Gsub(r) in terms of the parameters applicable to the solar wind and the diurnal anisotropy. This helps us calculate the rigidity (R) dependence of the diffusion coefficent K parallel. We find that K parallel = 1.37 x 10/sup 18/ Rsup(0.6) m/sup 2/s/sup -1/, where R is in gigavolts, and K perpendicular 1.08 x 10/sup 18/ m/sup 2/s/sup -1/. Our results are discussed.
1987-01-01
Energy Technology Data Exchange (ETDEWEB)
A combined PVD/PECVD process for the vacuum deposition of titanium containing amorphous hydrogenated carbon films is described. Elemental compositions of the deposited films have been determined by in situ core level photoelectron spectroscopy (XPS). The long-term stability of the plasma process has been demonstrated. Target poisoning has not been observed. We have fabricated optical selective surfaces by the deposition of a-C:H/Ti multilayers onto aluminum substrates. Even though we have not optimized layer thicknesses and stoichiometries so far, the experimental results are promising: solar absorptance {alpha}{sub S} of 0.876 and thermal emittance {epsilon}{sub 100C} of 0.061 have been achieved yielding an optical selectivity sis defined as{alpha}{sub S}/{epsilon}{sub 100C} of 14.4. Accelerated aging tests of these coatings have demonstrated their aging stability: the service lifetime is predicted to amount to more than 25 years. Raman ...
2000-01-31
Selective emitters for thermophotovoltaic solar energy conversion
Energy Technology Data Exchange (ETDEWEB)
The performance of a thermophotovoltaic (TPV) converter for solar energy is compared with that of direct solar energy conversion by silicon and germanium solar cells. The optical selectivity of an intermediate emitter is computed. Experimental results on selective emission, based on selectively emitting materials and on antireflection coatings on metals, are reported. For a TPV converter equipped with silicon solar cells, no selective emitter is found to yield better results than would be obtained by direct conversion. A TPV converter with germanium cells operating with a ThO/sub 2/-coated tungsten emitter, however, may achieve a conversion efficiency superior to that of direct solar energy conversion by either silicon or germanium solar cells.
1983-12-01
Comparison of advanced engines for parabolic dish solar thermal power plants
A paraboloidal dish solar thermal power plant produces electrical energy by a two-step conversion process. The collector subsystem is composed of a two-axis tracking paraboloidal concentrator and a cavity receiver. The concentrator focuses intercepted sunlight (direct, normal insolation) into a cavity receiver whose aperture encircles the focal point of the concentrator. At the internal wall of the receiver the electromagnetic radiation is converted to thermal energy. A heat engine/generator assembly, which is mounted directly behind th receiver, then converts the thermal energy captured by the receiver to electricity. Developmental activity has been concentrated on relatively small power modules which employ 11- to 12-m-diam dishes to generate nominal power levels of approximately 20 kW. A comparison of advanced heat engines for use on the dish power module is presented in terms of the performance potential of each engine as weighed against ...
1982-09-01
Carmanah Technologies Corporation 2004 annual report
International Nuclear Information System (INIS)
British Columbia-based Carmanah Technologies is a world leader in the design, manufacture and supply of patented solar-powered light emitting diode (LED) lighting solutions. As a leading alternative energy manufacturer, it was the first company to integrate LEDs with solar chargers and battery power storage. Carmanah products have high-end assembly, minimal size, maximized performance and field-proven reliability. The products have been used in public transit applications, roadway lighting, and for general aviation lighting solutions. In 2004, their products saved the equivalent of 6,705 metric tonnes of carbon dioxide. This annual report includes information on the company's net earnings and investor profiles. The company has large markets for its products with little competition. It has a strong management team and its funding places it in a position to capitalize on current and emerging technologies. The company's energy resource ...
2005-01-01
Energy Technology Data Exchange (ETDEWEB)
Chromium containing amorphous hydrogenated carbon films (a-C : H/Cr) have been prepared by simultaneous rf plasma activated chemical vapour deposition of methane and magnetron sputtering of a chromium target. During deposition the substrates were heated (up to 300C) and DC biased (-200 and -600 V) in order to obtain films with high chemical stability. Constant temperature tests were performed at 250C in air with coatings deposited on silicon substrates. The degradation of the coatings was monitored by Raman spectroscopy and reflectance and transmission measurements. The main degradation mechanisms are discussed and the relevant parameters which improve the durability of the coatings are presented. Furthermore, the durability of solar selective, multilayered coatings which were deposited on copper sheets was investigated. Based on accelerated aging tests at different temperature loads in air (at 220C, 250C and 300C) and in a humid environment ...
1998-07-13
Energy Technology Data Exchange (ETDEWEB)
An analysis was perfonned on the mid-latitude scintillation and coherence frequency bandwidth (Fcoh) using transionospheric VHF signal data. The data include 1062 events spanning from November 1997 to June 2002. Each event records FORTE satellite received VHF signals from LAPP located at Los Alamos, New Mexico. Fcohs were derived to study scintillation characteristics on diurnal and seasonal variations, as well as changes due to solar and geomagnetic activities. Comparisons to the VHFIUHF coherence frequency bandwidth studies previously reported at equatorial and mid-latitude regions are made using a 4th power frequency dependence relationship. Furthennore, a wideband ionospheric scintillation model, WBMOD, was used to estimate Fcohs and compared with our VHF Fcoh values. Our analysis indicates mid-latitude scintillation characteristics that are not previously revealed. At the VHF bottom frequency range (3035 MHz), distinguished smaller Fcohs ...
2008-01-01
Renewable energy forecasts for solar applications : an Environment Canada perspective
Energy Technology Data Exchange (ETDEWEB)
The Meteorological Service of Canada has made weather datasets available in real-time on the Internet, for use by those with an interest in solar applications. Ensemble weather models can be used to produce medium range forecasts of weather events and to predict the likely available kilowatt-hours (kWhrs) of solar energy. As such, solar sites can maximize their harvest and use of solar energy. This presentation highlighted several different types of renewable energy forecasts obtained from weather models, including forecasts of expected kWhrs from solar panels and wind turbines, daily forecasts of expected solar heated water volumes and forecasts of water collection potential from impending precipitation events. The value of renewable energy forecasts in helping the solar energy sector monitor daily energy loads as well as daily and weekly ...
2006-07-01
Activation of Polymethyl-Methacrylate by Proton Beam
International Nuclear Information System (INIS)
Activation has been used for many kinds of useful applications, such as use of the radioisotopes for diagnosis and treatment of cancer, and wear (or corrosion) investigation for using thin layer activation (TLA) technique, etc. But activation also has severe problems for the post-processing of the samples; such as time-loss, inconvenience of sample handling, personal radiation safety, etc. For in-vitro experiments, we observed death of tumor cells by proton irradiation. The use of large activated container material can cause erroneous results in this case. To solve these problems, we studied why the samples were activated and how the level of the activation could be reduced. In proton beam irradiation experiments, the target materials could be defined as the container and sample itself. We could easily reduce activation ...
2010-10-01
Catalytic desulfurization of organic sulfur compounds over zeolite catalysts
Energy Technology Data Exchange (ETDEWEB)
In the dehydrodesulfurization of ethanethiol at 400/sup 0/C, the activities of sodium X, Y, and A zeolites decreased in the order given as did the activities of nickel, cobalt, zinc, cadmium, copper, silver, lead, manganese, barium, calcium, sodium, and iron Y zeolite catalysts. A volcano-shape order was observed between the catalytic activity and the electronegativity of the metal ions. The changes in the activity of hydrogen Y zeolite catalyst in ethanethiol dehydrodesulfurization and cumene dealkylation by calcination agreed with the decrease in the Broensted acidity but were independent of Lewis acidity. For hydrodesulfurization of thiophene, the activities of nickel, cobalt, copper, and silver Y zeolite catalysts decreased in the order given and were greater than for a commercial hydrodesulfurization catalyst; reduced and presulfided catalysts showed ...
1980-01-01
Solar flux distribution in cavity receivers with parabolic dish collector
Energy Technology Data Exchange (ETDEWEB)
Thermal absorption with its combined thermal and mechanical loads in a solar receiver does depend significantly on the distribution of incident solar radiation. For a cavity receiver with paraboloid collectar a method is derived which enables the calculation of solar radiation distribution on the areas inside the receiver. The theoretical bases are presented first, and a subsequent example shows the influence of the most important geometric parameters on the distribution of solar radiation.
1982-01-01
Energy Technology Data Exchange (ETDEWEB)
This book comprises an up-to-date description of the astrophysical characteristics of the sun, including modern techniques used in solar research. Provides an historical background of solar research and techniques and covers the necessary astrophysics for solar studies, energy generation in the interior, the convection zone, the non- thermally heated layers, and solar wind are described in detail. Also considers the sun in relation to other stars, including information on its variable outputs of light, charged particles, and fields.
1990-01-01
Drying of medicinal plants with solar energy utilization
Energy Technology Data Exchange (ETDEWEB)
In the paper, a potential of solar energy for drying of medicinal plants in Polish conditions is estimated and development of solar drying technologies is presented. The results of economic assessment of flat-plate solar collectors applied for drying of medicinal plants on a farm are promising. In some specific conditions, e.g. drying of wild grown medicinal plants in remote areas, even application of photovoltaic modules for driving of a fan of a solar dryer is a profitable option and enables easy control of the drying air temperature.
1997-10-01
The physical properties of extra-solar planets
International Nuclear Information System (INIS)
Tremendous progress in the science of extrasolar planets has been achieved since the discovery of a Jupiter orbiting the nearby Sun-like star 51 Pegasi in 1995. Theoretical models have now reached enough maturity to predict the characteristic properties of these new worlds, mass, radius, atmospheric signatures, and can be confronted with available observations. We review our current knowledge of the physical properties of exoplanets, internal structure and composition, atmospheric signatures, including expected biosignatures for exo-Earth planets, evolution, and the impact of tidal interaction and stellar irradiation on these properties for the short-period planets. We discuss the most recent theoretical achievements in the field and the still pending questions. We critically analyze the different solutions suggested to explain abnormally large radii of a significant fraction of transiting exoplanets. Special attention is devoted to the recently discovered ...
2010-01-01
The data obtained by the recent modern sky surveys enable detailed studies of the stellar distribution in the multi-dimensional space spanned by spatial coordinates, velocity and metallicity, from the solar neighborhood all the way out to the outer Milky Way halo. While these results represent exciting observational breakthroughs, their interpretation is not simple. For example, traditional decomposition of the thin and thick disks predicts a strong correlation in metallicity and kinematics at $\\sim$1 kpc from the Galactic plane; however, recent SDSS--based work has demonstrated an absence of this correlation for disk stars. Instead, the variation of the metallicity and rotational velocity distributions can be modeled using non--Gaussian functions that retain their shapes and only shift as the distance from the mid--plane increases. To fully contextualize these recent observational results, a detailed comparison with ...
2008-01-01
Kepler Mission Stellar and Instrument Noise Properties
Kepler Mission results are rapidly contributing to fundamentally new discoveries in both the exoplanet and asteroseismology fields. The data returned from Kepler are unique in terms of the number of stars observed, precision of photometry for time series observations, and the temporal extent of high duty cycle observations. As the first mission to provide extensive time series measurements on thousands of stars over months to years at a level hitherto possible only for the Sun, the results from Kepler will vastly increase our knowledge of stellar variability for quiet solar-type stars. Here we report on the stellar noise inferred on the timescale of a few hours of most interest for detection of exoplanets via transits. By design the data from moderately bright Kepler stars are expected to have roughly comparable levels of noise intrinsic to the stars and arising from a combination of fundamental ...
2011-01-01
New sets of cross sections for the production of krypton isotopes from targets of Rb, Sr, Y, and Zr were constructed primarily on the bases of experimental excitation functions for Kr production from Y. These cross sections were used to calculate galactic-cosmic-ray and solar-proton production rates for Kr isotopes in the moon. Spallation Kr data obtained from ilmenite separates of rocks 10017 and 10047 are reported. Production rates and isotopic ratios for cosmogenic Kr observed in ten well-documented lunar samples and in ilmenite separates and bulk samples from several lunar rocks with long but unknown irradiation histories were compared with predicted rates and ratios. The agreements were generally quite good. Erosion of rock surfaces affected rates or ratios for only near-surface samples, where solar-proton production is important. There were considerable spreads in predicted-to-observed production ...
1979-01-01
Wounding Nicotiana tabacum Leaves Causes a Decline in Endogenous Indole-3-Acetic Acid 1
UK PubMed Central (United Kingdom)
We have previously observed that auxin can act as a repressor of the wound-inducible activation of a chimeric potato proteinase inhibitor II-CAT chimeric gene (pin2-CAT) in transgenic...Full Text Available
1991-07-01
... time, sucrase activity, a marker of intestinal epithelium (Matsushita, 1983) was observed in epithelial cells with CdxA ... PubMed, CSAIshii, Y., K. Fukuda, H. Saiga, S. Matsushita, and S. Yasugi. 1997. E...
Stabilization of lignin peroxidases in white rot fungi by tryptophan.
UK PubMed Central (United Kingdom)
Supplementation of various cultures of white rot fungi with tryptophan was found to have a large stimulatory effect on lignin peroxidase activity levels. This enhancement was greater than that observed...Full Text Available
1997-07-01
UK PubMed Central (United Kingdom)
IntroductionPrevious observations suggest that active systemic juvenile idiopathic arthritis (sJIA) is associated with a prominent erythropoiesis gene-expression signature. The aim...Full Text Available
2010-01-01
Far-Red Light-Induced Changes in Intracellular Potentials of Spinach Mesophyll Cells
UK PubMed Central (United Kingdom)
In green plants, the large bioelectric changes that photosynthetically active light stimulates make it difficult to observe electrical potential changes related to phytochrome photoconversion. As a...Full Text Available
1983-11-01
Sep 9, 2009... a French Ariane rocket successfully launched a new Earth-observing satellite ... The payload is a pair of identical sensors known as "high-resolution ... the resulting image) are activated simultaneously by incoming radiation; ...
UK PubMed Central (United Kingdom)
Curcumin is a natural product currently in human clinical trials for a variety of neoplastic, preneoplastic, and inflammatory conditions. We previously observed that, in cultured cells, curcumin exhibits...Full Text Available
2009-01-08
UK PubMed Central (United Kingdom)
BackgroundVariable platelet response to clopidogrel has been widely observed. Studies have shown that the mean aggregation response to clopidogrel can be changed...Full Text Available
2009-05-01
Carbon Dioxide Fixation in Soybean Roots and Nodules
UK PubMed Central (United Kingdom)
These studies demonstrate that soybean (Merr) roots and nodules possess an active system for fixing CO2. The maximum rates of CO2 fixation observed for roots and nodules of intact...Full Text Available
1981-04-01
Thermal convection loop study of corrosion of alloy 800 in molten NaNO/sub 3/-KNO/sub 3/
Energy Technology Data Exchange (ETDEWEB)
Maximum metal loss rate of Alloy 800 coupons was about 0.5 mil/year and occurred at the maximum temperature of 600/sup 0/C. Significantly greater oxide penetration into the alloy occurred in unabraded as-received tubing. Since the corrosion rate of unabraded tubing was less temperature sensitive than polished coupons, and attained a maximum value at temperatures in the range of 550 to 565/sup 0/C, a value of 1 mil/year should be used as the corrosion rate for design purposes. Because daily thermal cycling is inherent in solar central receiver operation, oxidation and chromium depletion rates can be expected to increase if surface oxide layers spall. The oxide layers formed on Alloy 800 appeared to be adherent, and adherence will benefit further from growth-derived compressive stresses in oxide layers on the salt-exposed inner diameter of receiver tubes. Since the lower duty factor in diurnal solar service may offset the accelerated metal loss ...
1983-01-01
The cometary activity of Centaur P/2004 A1 (LONEOS)
British Library Electronic Table of Contents (United Kingdom)
Abstract P/2004 A1 (LONEOS) is one of the few active objects in the dynamical class of Centaurs. It has been recently injected into an inner orbit with a perihelion distance-q-= 5.5 au. The aim of this paper is to characterize the dust coma of this peculiar object, 2.5 yr after its first -new- perihelion passage inside the Solar system. Broad-band visible images taken at the TNG telescope in 2007 February were analysed in order to characterize the dust coma of the Centaur: it was still quite active at-rh-= 6.5 au post-perihelion, with a coma and a well-developed wide tail-like structure, with a measured-R-Af= 162 10-cm in an aperture radius = 104 km. The (V---R) colour and the reddening values depict a scenario of a slightly red dust coma. A dust mass-loss rate of--= 133 kg-s-1 is derived ...
2011-01-01
International Nuclear Information System (INIS)
High-resolution observations are presented of the 300-kpc jet in the giant radio galaxy NGC 6251. The width of the jet is resolved over most of its length, and the axis of the jet wiggles with an amplitude increasing linearly with distance from the nucleus. Polarization data are used to derive densities of cold matter in the jet and, from the argument that the jet must form the lobe in a time equal to the age of the lobe, the speed of the jet is estimated as c/20. The energetics of the jet are then dominated by the bulk flow along it of cold matter at a rate of 1 solar mass yr"-"1. The jet appears to be confined; the wiggle of its axis is probably due to oscillations of the direction of the collimator with a period of about 6 x 10"6 yr. (author).
The dark matter halos of Draco and Ursa Minor
International Nuclear Information System (INIS)
Published density profiles and central velocity dispersions place important constraints on the stellar velocity ellipsoid and on the distribution of dark matter (DM) in the dwarf spheroidal galaxies Draco and Ursa Minor. Central velocity dispersions of 9 km/s are adopted for Draco and 11 km/s for Ursa Minor. Then, for an isotropic stellar velocity distribution, the central DM densities are 0.8 and 1.0 solar mass/cu pc, respectively, if visible and dark matter have the same core radius. If DM has a much larger core radius than visible matter but nevertheless dominates the potential, these densities are reduced by a factor of 2. Central DM densities can be lower than this only if the stellar velocity distribution is anisotropic. Simple two-component King models are used to investigate this and to look for the smallest DM densities that are consistent with the observations. 36 refs.
Simple chemical method for nanoporous network of In2S3 platelets for buffer layer in CIS solar cells
British Library Electronic Table of Contents (United Kingdom)
Indium sulfide thin films consisting of porous network of nanoplatelets, have been deposited using chemical bath deposition (CBD) method onto the tin-doped indium oxide (ITO) coated glass substrate. Aqueous solutions of indium sulfate and thioacetamide have been used as indium and sulfur precursors. As a complexing agent, acetic acid was used. The chemically deposited indium sulfide thin films were examined for their structural, surface morphological and optical characterizations. The X-ray diffraction analysis revealed the formation of the cubic b-In2S3 onto the substrate. From scanning electron micrograph, it is observed that the surface of substrate is covered by nanoporous platelets type morphology. The optical studies showed a direct band gap of 2.84eV for indium sulfide platelets. Ph...
2008-01-01
British Library Electronic Table of Contents (United Kingdom)
Possible factors regulating phytoplankton variability in the Arabian (Persian) Gulf were analyzed on the basis of satellite observations and meteorological data (1997-2009), including remotely-sensed chlorophyll a concentration (CHL), sea surface temperature, wind, solar radiation, precipitation, and aerosols. Shallow waters of northwestern Gulf influenced by Shatt Al-Arab River discharge were more productive than open Gulf waters, although seasonal CHL patterns in this and other shallow regions looked unrealistic likely because the CHL signal was obscured by bottom reflection. Therefore our further analyses focused on the open Gulf waters, which show a subtropical seasonal CHL cycle with maximum in winter and minimum in spring-summer. This cycle, however, was decoupled from the seasonal e...
2010-01-01
Progress Report Towards the ICANOE Detector
We present a proposal for a combined ICARUS & NOE general purpose detector, to be installed in Hall B of the Gran Sasso Laboratory.The main scientific goal is the one of elucidating in a comprehensive way the pattern of neutrino $9 masses and mixings, following both (1) the S-KAM results and (2) the predictions on atmospheric neutrinos of the large solution of the Solar Neutrinos deficit. To achieve these goals, the experimental method is based upon the $9 complementary and simultaneous detection of CERN beam (CNGS) and cosmic ray (CR) events. This is made possible because of the complete isotropy of the detection technique. For the currently allowed values of the S-KAM results, both $9 CNGS and cosmic ray data will give independent measurements and provide a precise $(sin^{2}2\\theta; \\Delta m^{2})$ determination rather than a wide band of allowed values. Since we can observe and unambiguously identify $9 $\
1999-01-01
On the disrupted magnetic braking model for the period gap of cataclysmic variables
International Nuclear Information System (INIS)
The disrupted magnetic braking theory for the period gap of cataclysmic variable systems is used to study the binary evolution of low-mass main-sequence-like stars with white dwarf companions. The model is able to reproduce the observed location and width of the gap provided that the average mass transfer rates above the upper edge of the gap are greater than about 1.9 x 10 to the -9th solar masses/yr. For the case of angular momentum loss by magnetic braking, the slope of the mass transfer rate with respect to orbital period is shown to range from 3.4 to 3.7. For the evolutionary sequences considered, the He-3 abundance at the surface of the secondary exceeds 0.0015 after the complete mixing phase, resulting in modifications in the nuclear burning development of nova explosions. 31 refs.
Energy Technology Data Exchange (ETDEWEB)
Water vapor is well known to be a critical component in many aspects of atmospheric research, such as radiative transfer and cloud and aerosol processes. This requires both improved measurements of the columnar water vapor and its profiles in the atmosphere in a wide range of conditions, and adjustment of water vapor parameterizations in radiation codes including the perfection of spectroscopic parameters. In this paper we will present the results of comparison of our calculations and downward solar fluxes measured with Rotating Shadowband Spectroradiometer under conditions of horizontally homogeneous clouds. We also will discuss the sensitivity of atmospheric radiation characteristics to variations of water vapor in the band 940 nm: these results may be useful for development of new methods of retrieval of the total column water vapor content (WVC) in the atmosphere from data of radiation observations.
2005-03-18
Energy Technology Data Exchange (ETDEWEB)
Lifetime observations on a group of 358 rhesus monkeys indicate that life expectancy loss from exposure to protons in the energy range encountered in the Van Allen belts and solar proton events is influenced primarily by the dose rather than the energy of radiation. After 24 years, life expectancy losses from similar surface doses of low-LET (138-2300 MeV) and high-LET (32-55 MeV) protons are not significantly different, but the high-LET protons are associated with more deaths in the early years, while the low-LET protons contribute more to mortality in later years. In males, the most significant cause of life shortening is nonleukemia cancers.
1990-05-01
Lithium abundances of southern F, G, and K dwarfs
Energy Technology Data Exchange (ETDEWEB)
Observations are reported of the lithium feature (6708 A) in some bright southern stars, most of which are F, G, or K dwarfs. Three of these stars have been suggested as belonging to the Ursa Major Group. Two of these three have the large Li abundance and strong Ca II H and K emission expected of such young stars. The third potential Ursa Major Group member has little Li, but is also not a true kinematic member. No stars were found with abnormal (Li-6)/(Li-7) ratios, in accord with other recent analyses. Thus it appears that all stars have (Li-6)/(Li-7) near the solar/terrestrial value of 0.08. 31 references.
1985-01-01
Interactions of SO{sub x} and NO{sub x} with soot
Energy Technology Data Exchange (ETDEWEB)
Studies of the adsorption of oxides of sulfur and nitrogen, and their coadsorption, on black carbon in the form of n-hexane soot have been carried out by microgravimetry, EPR and FTIR spectroscopy over a wide range of experimental conditions. The mechanisms of adsorption of O{sub 2} and NO{sub 2} are entirely different, as reflected by adsorption isotherms, the behavior of carbon`s unpaired electrons, the spectral features of surface species formed, mass changes during adsorption-desorption cycles, and an essential lack of competition for surface sites. Significant effects of temperature, water, SO{sub 2} and NO{sub 2} concentration, O{sub 2}, simulated solar radiation, and the presence of trace metals, have been observed and interpreted.
1996-10-01
Constraining SN Ia Models Using X-ray Spectra of Clusters of Galaxies
We present constraints on theoretical models of Type Ia SNe using spatially resolved ASCA X-ray spectroscopy of four galaxy clusters: Abell 496, Abell 2199, Abell 3571 & Perseus. All four clusters have central Fe abundance enhancements and an ensemble of abundance ratios are used to show that most of the Fe in the central regions of the clusters comes from SN Ia. At the center of each cluster, simultaneous analysis of spectra from all ASCA instruments shows that the Ni to Fe abundance ratio (normalized by the solar ratio) is ~ 4. We use the Ni/Fe ratio as a discriminator between SN Ia explosion models: the Ni/Fe ratio of ejecta from the "Convective Deflagration" model W7 is consistent with the observations, while those of "delayed detonation" models are not consistent at the 90% confidence level.
2000-01-01
Comparative planetology, climatology and biology of Venus, Earth and Mars
British Library Electronic Table of Contents (United Kingdom)
Spacecraft studies of the three terrestrial planets with atmospheres have made it possible to make meaningful comparisons that shed light on their common origin and divergent evolutionary paths. Early in their histories, all three apparently had oceans and extensive volcanism; Mars and Earth, at least, had magnetic fields, and Earth, at least, had life. All three currently have climates determined by energy balance relationships involving carbon dioxide, water and aerosols, regulated by solar energy deposition, atmospheric and ocean circulation, composition, and cloud physics and chemistry. This paper addresses the extent to which current knowledge allows us to explain the observed state of each planet, its planetology, climatology and biology, within a common framework. Areas of ignorance...
2011-01-01
A satellite born charged particles telescope for the study of cosmic ray nuclei
Energy Technology Data Exchange (ETDEWEB)
The description of the high energy particle telescope NINA for the study of cosmic ray nuclei is presented. The instrument will be installed on board of the Resource 01 satellite and will fly on a polar orbit at 690 Km. The telescope consists on a pile of 16 detecting planes each of them is composed by two silicon strip detectors with perpendicular strips and has a total area of 60x60mm{sup 2}. The experiment goals are the study of cosmic ray protons and nuclei in the energy range 12-100 MeV/amu. It will be sensitive to the anomalous component and will also make the observation of the large solar flare events and geophysical phenomena as well. This experiment is the first step of the program RIM whose goal is the satellite study of anti particles in primary cosmic rays.
1995-09-01
Wafer and Solar Cell Characterization by GT-PVSCAN6000
The PVSCAN is an instrument designed to characterize silicon solar cell materials and devices. It performs a host of measurements that yield spatial maps of dislocation density, grain distribution, reflectance, and photoresponses from near-junction and the bulk of a solar cell.
2002-08-01
Changes of the electron density distribution during MHD activity in CHS
Energy Technology Data Exchange (ETDEWEB)
Density oscillations induced by MHD activities were observed in NBI heated plasmas on CHS by using an HCN laser interferometer. The accompanied changes of the density profiles were also observed. The oscillations are composition of m=0 sawteeth like crash and m=2 sinusoidal oscillations as a post courser of the crash. Possible models of the oscillation structure are examined in order to explain experimental data of the interferometer. Rotating plasma core, which is hollow profile and keeps constant elongation of the flux surface can explain amplitude and phase distribution of the sinusoidal oscillation. (author)
2000-09-01
Bone scanning after muscle-pedicle bone graft for femoral neck fracture, (1). Preliminary report
Energy Technology Data Exchange (ETDEWEB)
sup(99m)Tc-MDP bone scintigraphy was performed on patients who received muscle-pedicle bone graft. In each of the bone head and the bone graft, a time-activity curve was obtained. In this muscle-pedicle bone graft, active revascularization and marked osteogenesis, which suggested rapid bone repairing, were observed. The bone scintigraphy was considered to be useful in observing the result of bone grafts, blood circulation, and time of bone fusion, and of value for early detection of secondary changes.
1982-04-01
International Nuclear Information System (INIS)
This paper reviews three key initiatives undertaken in the historical city of Oxford to bring about reductions in energy-related CO_2 emissions on a city-wide scale. The author has been part of all the three initiatives. In 2002, a collaborative partnership between academia, industry and city council started the Oxford Solar Initiative (OSI) which uses a community-based approach to help households and organisations in Oxford, financially and technically, to install solar energy systems and energy efficiency measures in buildings. So far OSI has facilitated the installation of 80 active solar systems, over 450 energy efficiency measures and 3,000 low energy bulbs. The scientific basis of OSI is a GIS-based DECoRuM model which estimates and maps baseline energy use and CO_2 emissions on a house-by house level, identifies 'pollution' hotspots, predicts the potential for reductions in CO_2 emissions and ...
2007-06-04
The solar energy in Lebanon: an inexhaustible and economical energy
International Nuclear Information System (INIS)
The article describes the energy in Lebanon. In 1995, 97% of the imported energy was based on hydrocarbons. Fuel and gas oil present 66% of the final energy. Air pollution is mainly caused by the transportation sector (vehicles and buses...) which presents 70% of the global atmospheric pollution. Renewable energy such as biomass, fossil energy, hydro-energy, solar energy... are also described. The solar energy was defined as a best solution that preserve health in Lebanon. The different applications of the solar for energy production is discussed: photovoltaic , thermal heating, sanitary hot water, electrical heaters, solar water heaters...In conclusion, solar heaters economize 80% of the annual energy expenses
1997-06-01
British Library Electronic Table of Contents (United Kingdom)
A detailed knowledge about the dynamics of phytoplanktonic photosynthesis and respiration is crucial for the determination of primary productivity in open oceans as well as for biotechnological applications. The dynamics are best studied in photobioreactors that are able to simulate natural conditions in such, that light can be modulated not only diurnally but also mimicking effects of solar elevation angle from sunrise to sunset, variable cloudiness, light modulation in refractory sun flecks due to water waves, or light intermittence due to turbulent flow in dense suspensions. In addition, high performance photobioreactors ought to be able to monitor in real time photosynthetic and respiratory activities as well as culture growth. Here, we demonstrate performance of a newly designed bench...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
A new band gap profile (exponential profile) for the active layer of the a-SiGe:H single junction cell has been designed and experimentally demonstrated. In this paper we compare its optical and electrical characteristics with the two more common profiles: the U- and V-shapes. As predicted by the simulations, the new profile combines the advantages of both profiles. Like the V-shape, the exponential shape reduces the amount of Ge in the i-layer, decreasing both the space charge defect density inside the i-layer and the recombination losses. It also improves the electric field. At the same time, the exponential shape generates the same current density as the U-shape.
2002-04-01
FY 1992 Measurements and Characterization Branch annual report
Energy Technology Data Exchange (ETDEWEB)
The Measurements and Characterization Branch actively supports the advancement of DOE/NREL goals for the development and implementation of the solar photovoltaic (PV) technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility that Is capable of providing information on the full range of PV components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of Pv technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. The Measurements and Characterization Branch encompasses seven coordinated research groups, providing integrated research and development that covers all aspects of photovoltaic materials/devices ...
1993-03-01
Three generation vacuum oscillations and the solar neutrino problem
We investigate the solar neutrino problem in the scenario of three generation neutrino oscillation hypothesis, taking into account other phenomenological constraints to the neutrino mixing and mass parameters.
1994-01-01
The formation and degradation of Ti-Ag and Ti-Pd-Ag solar cell contacts
Ti-Ag and Ti-Pd-Ag solar cell contacts structure and degradation dependence on high temperature and humidity environmental exposure
1970-01-01
Energy Technology Data Exchange (ETDEWEB)
A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror thereby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.
1981-07-01
Energy Technology Data Exchange (ETDEWEB)
Conference paper regarding research in the use of freeze prevention for passive solar domestic water heating systems.
2006-05-01
NASA - Pico-Satellite Solar Cell Experiment (PSSC)
Jun 10, 2011 ... The PSSC is a picosatellite designed to test the space environment by providing a testbed to gather data on new solar cell technologies.
Laser-assisted solar cell metallization processing - NASA ...
Oct 15, 1985 ... Title: Laser-assisted solar cell metallization processing. No Digital Version Available: Go to Tips on Ordering ...
High-Temperature Solar Cell Development - GLTRS - NASA
High-Temperature Solar Cell Development. Geoffrey A. Landis,. NASA John Glenn Research Center. 21000 Brookpark Road, Cleveland, OH 44135. Danielle ...
Foveo-macular retinitis, solar retinopathy, and trauma.
UK PubMed Central (United Kingdom)
Three patients are described with foveal lesions resembling minute holes following trauma. The similarity of the lesions to foveomacular retinitis and solar retinopathy suggests that all these conditions...Full Text Available
1978-08-01
Division of Solar Energy - NASA Technical Reports Server
Metal-semiconductor solar cells reported to date exhibit inherently low output voltages. This effect isa consequence of high diode "saturation" ...
Sputtering of glass coatings on cadmium sulfide thin film solar cells
1965-01-01
BIG BEAR SOLAR OBSERVATORY - NASA Technical Report Server (NTRS)
replacing the KDP crystal, and introducing computer programs for accumulation of an almost unlimited number of frames. The calibration procedure using solar ...
Galactic deuterium abundance as a test of cosmological models
Energy Technology Data Exchange (ETDEWEB)
The problem on change of deuterium abundance in the process of galactic evolution (star evolution, supernova explosions, nucleosynthesis in supermassive objects) is considered. It is shown that the observable deuterium quantity in the interstellar medium must correspond to its cosmological abundance. This conclusion is independent of the rate of accretion of intergalactic gas by Galaxy. The effect of hypothetical pregalactic active objects on cosmological deuterium is small. It is poind out that observations of interstellar deuterium in absorbtion at lambda=91.6 cm are significant.
1982-02-01
In this activity, students will make a turbidity current. They will discover how fluids of differing densities interact with one another, learn some ways the densities of fluids can be changed and observe how density currents transport and deposit tremendous amounts of sediment in lakes and in the ocean. Additional options allow students to create and observe different kinds of density currents.
Radon transport in an activated charcoal canister
Energy Technology Data Exchange (ETDEWEB)
The transport of Rn through activated charcoal was modelled for a charcoal canister used for surface emanation measurements. Derived Rn concentration distributions in full and half charcoal charges were compared with measured Rn profiles. The distributions were also compared with an empirical expression for the measured profiles. Close agreement was observed between the measured, empirically generated and derived profiles. The influence of temperature and humidity on Rn accumulation and transport is also discussed.
1989-02-01
Active Site of ?-Chymotrypsin Activation by Association-Desolvation
UK PubMed Central (United Kingdom)
High reactivity toward α-chymotrypsin is observed for derivatives of β-arylpropionic acids of varied structure—L-α-acylamido compounds, D-cyclized compounds, and, now,...Full Text Available
1970-06-01
Optimizing the design of solar energy greenhouses
Energy Technology Data Exchange (ETDEWEB)
In Canada, the cost of heating is a major expense in the operation of greenhouses in the winter season, inhibiting greenhouse production in winter months in most part of the country. Alternative energy sources, such as solar energy and biomass energy may offer an economically feasible heating alternative. A solar energy greenhouse technology developed in northern China for winter vegetable production has demonstrated good potential for Manitoba winter conditions. The design and performance of solar energy greenhouses depend on the geographical location. Therefore, in order to optimize the design of solar greenhouses with respect to the latitude of the location for maximum solar radiation gain, a theoretical analysis was performed that analyzed parameters such as greenhouse length and the roof slope. This paper described the methodology of the study, including a description of ...
2006-07-01
One-electron reduction of chloroperoxidase by radiolytically generated electrons
Energy Technology Data Exchange (ETDEWEB)
Upon irradiation of aqueous ethylene glycol/water solutions of native chloroperoxidase (CPO) with {sup 60}Co-gamma rays at 77K one observes the one-electron reduction of the enzyme active site by radiolytically generated thermolyzed electrons. In the present study the first absorption spectrum of a low-spin ferrous form of CPO is reported which has peaks at 438, 532 and 563 nm, similar to those observed previously for cytochrome P-450. All previously described ferrous forms of CPO are high spin. In order to observe the final results of the CPO reaction with electrons, the spectral changes of native enzyme after room temperature-gamma-irradiation have also been investigated. Evidence of changes is also presented probably connected with disruption of the tertiary structure of enzyme, correlated with decrease of enzyme activity.
1990-05-16
One-electron reduction of chloroperoxidase by radiolytically generated electrons
International Nuclear Information System (INIS)
Upon irradiation of aqueous ethylene glycol/water solutions of native chloroperoxidase (CPO) with "6"0Co-gamma rays at 77K one observes the one-electron reduction of the enzyme active site by radiolytically generated thermolyzed electrons. In the present study the first absorption spectrum of a low-spin ferrous form of CPO is reported which has peaks at 438, 532 and 563 nm, similar to those observed previously for cytochrome P-450. All previously described ferrous forms of CPO are high spin. In order to observe the final results of the CPO reaction with electrons, the spectral changes of native enzyme after room temperature-gamma-irradiation have also been investigated. Evidence of changes is also presented probably connected with disruption of the tertiary structure of enzyme, correlated with decrease of enzyme activity.
1990-05-01
GRBs Light Curves - Another Clue on the Inner Engine
The nature of the `inner engine' that accelerate and collimate the relativistic flow at the cores of GRBs is the most interesting current puzzle concerning GRBs. Numerical simulations have shown that the internal shocks' light curve reflects the activity of this inner engine. Using a simple analytic toy model we clarify the relations between the observed $ \\gamma $-rays light curve and the inner engine's activity and the dependence of the light curves on the inner engine's parameters. This simple model also explains the observed similarity between the observed distributions of pulses widths and the intervals between pulses and the correlation between the width of a pulse and the length of the preceding interval. Our analysis suggests that the variability in the wind's Lorentz factors arises due to a modulation of the mass injected into a constant energy flow.
2002-01-01
Structure and properties of Li2Zn2(MoO4)3 crystals activated with copper and chromium ions
British Library Electronic Table of Contents (United Kingdom)
Based on the corrected phase diagrams proper growth conditions for Li2Zn2(MoO4)3 crystals are selected. Large crystals (up to 100 mm), both impurity-free and activated by transition metal ions (Cu, Cr), are grown by the low-gradient Czochralski method. By the EPR method the charge state and structural position of copper and chromium ions are determined. The performed studies of luminescent properties show that for impurity-free crystals luminescence with ? = 388 nm with a two-exponential luminescence decay with ?1 = 2 ns and ?2 = 6 ns is observed at room temperature. At 77 K for both impurity-free crystals and those activated with transition metal ions luminescence with ? = 560 nm and the luminescence lifetime ? = 100 ns is observed, the intensity of luminescence with ? = 560 nm depending ...
2011-01-01
Caburization kinetics of alloy-800 in liquid sodium at 550_0C
International Nuclear Information System (INIS)
Preliminary observations on the isothermal carbon transfer in low-carbon Alloy-800 exposed in sodium with AISI-304 type of steel at 550_0 are reported. The alloy was found to undergo a carburization comparable or slightly lower than that observed for the AISI-304 stainless steel for carbon activities above 6 x 10 /sup -3/ at 550_0C, but was not found to decarburize below such a carbon activity value. In the examined range the chemical composition of the alloys does not affect the process out of the experimental uncertainty of measure. Conclusions concerning the effective diffusion for carbon in the alloy are formulated. Preliminary relationships were found for an empirical evaluation of the carburization of the Alloy-800 in sodium of known carbon activity.
Influence of local waste burning on atmospheric aerosol properties in urban environment
International Nuclear Information System (INIS)
Aerosols affect the radiative energy budget on both the regional and global scales. The wavelength-dependent aerosol optical depth (AOD) is a fundamental determinant of the amount by which extra-terrestrial incoming sunlight and outgoing terrestrial radiation are being attenuated in the atmosphere. The present study addresses the influence of local waste burning on aerosol characteristics, black carbon (BC) aerosol mass concentration and spectral solar irradiance using ground-based measurements over the tropical urban environment of Hyderabad, India. AOD has been observed to be maximum during burning days compared to normal days. Aerosol size spectra suggest bimodal distributions during pre-and post-burning periods and trimodal distributions during burning periods. Angstrom wavelength exponent estimated from spectral variation of AOD suggested dominance of accumulation mode particle loading during burning days compared to normal days. Diurnal ...
2006-03-01
Spatial Damping of Propagating Kink Waves Due to Resonant Absorption: Effect of Background Flow
Observations show the ubiquitous presence of propagating magnetohydrodynamic (MHD) kink waves in the solar atmosphere. Waves and flows are often observed simultaneously. Due to plasma inhomogeneity in the perpendicular direction to the magnetic field, kink waves are spatially damped by resonant absorption. The presence of flow may affect the wave spatial damping. Here, we investigate the effect of longitudinal background flow on the propagation and spatial damping of resonant kink waves in transversely nonuniform magnetic flux tubes. We combine approximate analytical theory with numerical investigation. The analytical theory uses the thin tube (TT) and thin boundary (TB) approximations to obtain expressions for the wavelength and the damping length. Numerically, we verify the previously obtained analytical expressions by means of the full solution of the resistive MHD eigenvalue problem beyond the TT and TB approximations. ...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The Atmospheric Radiation Monitor (ARM) uninhabited aerospace vehicle (UAV) program aims to develop measurement techniques and instruments suitable for a new class of high altitude, long endurance UAVs while supporting the climate community with valuable data sets. Using the Scaled Composites Proteus aircraft, ARM UAV participated in Mixed-Phase Arctic Cloud Experiment (M-PACE), obtaining unique data to help understand the interaction of clouds with solar and infrared radiation. Many measurements obtained using the Proteus were coincident with in-situ observations made by the UND Citation. Data from M-PACE are needed to understand interactions between clouds, the atmosphere and ocean in the Arctic, critical interactions given large-scale models suggest enhanced warming compared to lower latitudes is occurring.
2005-03-18
A Chandra Observation of Supernova Remnant G350.1-0.3 and Its Central Compact Object
We present a new Chandra observation of supernova remnant (SNR) G350.1-0.3. The high resolution X-ray data reveal previously unresolved filamentary structures and allow us to perform detailed spectroscopy in the diffuse regions of this SNR. Spectral analysis demonstrates that the region of brightest emission is dominated by hot, metal-rich ejecta while the ambient material along the perimeter of the ejecta region and throughout the remnant's western half is mostly low-temperature, shocked interstellar/circumstellar medium (ISM/CSM) with solar-type composition. The data reveal that the emission extends far to the west of the ejecta region and imply a lower limit of 6.6 pc on the diameter of the source (at a distance of 4.5 kpc). We show that G350.1-0.3 is likely in the free expansion (ejecta-dominated) stage and calculate an age of 600-1200 years. The derived relationship between the shock velocity and the electron/proton temperature ratio is ...
2011-01-01
Thermal performance of solar air collectors with a passive heat transfer augmentation technique
Energy Technology Data Exchange (ETDEWEB)
One of the main disadvantages of solar air collectors in practical applications is their relatively low efficiency. In this experimental investigation, the shape and arrangement of absorber surfaces of the collectors were reorganized to provide better heat transfer surfaces suitable for the passive heat transfer augmentation techniques. The performance of such solar air collectors with staggered absorber sheets was tested. The experimental results show that it is possible to provide 10 to 25% enhancement in the efficiency compared to the conventional solar air collectors. (authors)
2000-07-01
Energy Technology Data Exchange (ETDEWEB)
The conception of a solar receiver intended to equip a tower power-station has to combine multiple requirements: very highly concentrated solar flux, unsteady in time and space; necessity to obtain a high efficiency; respect of the physical limits of the materials and of the fluid. The description of Themis solar receiver and of its operation is preceded by considerations which have led to the choice of the cavity, of the fluid and of its circulation.
1982-01-01
Testing of solar cells for communication satellites
International Nuclear Information System (INIS)
... cadmium sulfides communications electrons performance testing physical
Tehachapi solar thermal system first annual report
Energy Technology Data Exchange (ETDEWEB)
The staff of the Southwest Technology Development Institute (SWTDI), in conjunction with the staff of Industrial Solar Technology (IST), have analyzed the performance, operation, and maintenance of a large solar process heat system in use at the 5,000 inmate California Correctional Institution (CCI) in Tehachapi, CA. This report summarizes the key design features of the solar plant, its construction and maintenance histories through the end of 1991, and the performance data collected at the plant by a dedicated on-site data acquisition system (DAS).
1993-05-01
Solar Radiation Pressure Binning for the Geosynchronous Orbit
Orbital maintenance parameters for individual satellites or groups of satellites have traditionally
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
This report contains a set of nomographs which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.
1982-09-01
Energy Technology Data Exchange (ETDEWEB)
A set of nomographs is presented which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.
1982-09-01
Simplified solar fraction estimation for space and water heating at DOD installations. Final report
Energy Technology Data Exchange (ETDEWEB)
A set of nomographs is provided which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorption coefficient, and collector overall loss coefficient.
1982-09-01
Development of solar agricultural dryers combined with PV modules and solar collectors
Energy Technology Data Exchange (ETDEWEB)
The intention of the research carried out was to develop photovoltaic driven solar heating systems applied for drying of medicinal plants in remote areas. Identification of hybrid photovoltaic - photothermal systems was done and discussion of technical features and applicability of such systems in agriculture is presented. Detail technical specification of PV powered medicinal plants solar dryer and cost effectiveness parameters are given. Operational and economic results obtained during testing of the dryer are promising. (orig.) 4 refs.
1997-12-31
Design of solar receivers for chemical energy storage and pyroheliometallurgy applications
Energy Technology Data Exchange (ETDEWEB)
A preliminary study of two different kinds of solar receivers (a rotating cavity receiver and a volumetric receiver) suitable to operate in the 1 kW solar facility at the University of Rome is presented. Possible applications of solar energy in the aluminum extraction from leucite and chemical storage by the CuO/Cu[sub 2]O cycle are presented and discussed. (author).
1992-01-01
The impact of solar flares and magnetic storms on humans
International Nuclear Information System (INIS)
Three classes of solar emanations, namely, photon radiation from solar flares, solar energetic particles, and inhomogeneities in the solar wind that drive magnetic storms, are examined, and their effects on humans and technological systems are discussed. Solar flares may disrupt radio communications in the HF and VLF ranges. Energetic particles pose a special hazard at low-earth orbit and above, where they can penetrate barriers such as spacesuits and aluminum and destroy cells and solid state electronics. Energetic solar particles also influence terrestrial radio waves propagating through polar regions. Magnetic storms may disturb the operation of navigation instruments, power lines and pipelines, and satellites; they give rise to ionospheric storms which affect radio communication at all latitudes. There is also a growing body of evidence that changes in the ...
Energy Technology Data Exchange (ETDEWEB)
A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the ...
2007-09-18
Rankine-Brayton engine powered solar thermal aircraft
Energy Technology Data Exchange (ETDEWEB)
A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, ...
2009-12-29
1-MW(th) solar-thermal conversion full-system experiment
Progress made during the first phase effort of the Solar-Thermal Full-System Experiment is summarized. This is one of a number of projects in the Solar-Thermal Subprogram involved with the development of solar central receiver hardware and systems for future use by utilities. The main emphasis is on systems that use Brayton-Cycle (gas turbine) equipment. The project summarized involves the planning and design of a complete Brayton-Cycle solar central receiver experimental system that would include all components of a commercial-size electric utility solar power plant. The objective of the overall project is to demonstrate the technical feasibility of a complete Brayton-Cycle, solar-fossil hybrid central receiver system. Major objectives of the Phase I effort summarized are to plan and design the experiment in detail and to organize a utility Test and Operating ...
1982-08-01
Cosmological Questions for the European Southern Observatory Very Large Telescope
The next decade promises an observational revolution which will change cosmology forever. The precise measurement of the angular anisotropy of the cosmic microwave background should specify to a few percent all of the parameters of the cosmological model which effect astrophysics. The growth of structure will then be determined (but not yet observed) until gravitational collapse becomes highly non-linear and stars, galaxies and active galactic nuclei (AGN) form. These processes are hard to model with basic physics because they are complex and allow a rich variety of expression. Instead observations will determine when the first stars and quasars formed, and how and when galaxies assembled. If we can reconcile the numerous contradictions which characterize the subject today, cosmology will become a mature subject, founded on the agreement between detailed, inclusive and realistic models, which make ...
1996-01-01
Energy Technology Data Exchange (ETDEWEB)
Three agricultural applications in a specially designed greenhouse solar system functioning as a multi-purpose solar air collector for crop production and curing/drying processes are examined. An automated hydroponic crop production system is proposed for the greenhouse solar system. Design criteria of the proposed system and its utilization of solar energy for root-zone warming are presented and discussed. Based upon limited testing of the hydroponic system considered, hydroponic production of greenhouse crops is believed reasonable to complement the year-round use of the greenhouse solar system. The hardware/software design features of a microcomputer-based control system applied in the greenhouse solar barn are presented and discussed. On-line management and utilization of incident solar energy by the microcomputer system are investigated ...
1987-01-01
Solar energy in buildings; L'energie solaire dans le batiment
Energy Technology Data Exchange (ETDEWEB)
This document gathers the presentations given at the first French national meetings of solar energy for the development of solar systems in buildings. The meeting was organized over two days. The first day comprises 4 workshops about: urbanism and planning, cultural acceptability of solar energy in buildings (the OPAC 38 housing association, point of view on an energy information point, the Freiburg (Germany) solar region and marketing examples), technical integration to the structure (Clipsol solutions), and economical criteria (compared impacts of R and D public photovoltaic programs (USA, Japan, Germany, France, Italy), financing of rehabilitation projects, global approach of solar photovoltaic energy, technical solutions and strategy of products development, why and how to make an economical analysis of solar energy applications in the building industry). ...
2003-07-01
Fractal properties of spatial distributions of aftershocks and active faults
Energy Technology Data Exchange (ETDEWEB)
The relationship between the fractal dimensions of spatial distributions of aftershocks and pre-existing active faults is examined. Fourteen mainshocks taking place in Japan were followed by aftershocks, and the aftershocks occur in swarms around the mainshocks. The epicentral distributions of the aftershocks exhibit fractal properties, and the fractal dimensions are estimated by using the two-point correlation integral. The pre-existing active fault systems observed in the 14 aftershock regions have fractal structures, and the fractal dimensions are estimated by using the box-counting method. A positive correlation between the estimated fractal dimensions is found, and it is independent on the mainshock magnitude. The correlation shows that aftershock distributions become less clustered with increasing the fractal dimensions of active fault systems. Namely, the fractal clusters of aftershocks are put ...
2004-01-01
International Nuclear Information System (INIS)
10%Pt/C catalysts were prepared by liquid reduction method. PTFE and Pt/ C catalysts were adhered to porous metal and hydrophobic Pt/C/PTFE catalysts were prepared. The structure and size of Pt crystal particles of Pt/C catalysts were analyzed by XRD, and their mean size was 3.1 nm. The dispersion state of Pt/C and PTFE was analyzed by SEM, and they had good dispersion mostly, but PTFE membrane could be observed on local parts of Pt/C/PTFE surface. Because of low hydrophobicity, Pt/C/ PTFE catalysts have low activity when the mass ratio of PTFE and Pt/C is 0.5: 1, and their catalytic activity increases markedly when the ratio is 1:1. When the ratio increases again, more Pt active sites would be covered by PTFE and interior diffusion effect would increase, which result in the decrease of catalytic activity of Pt/C/PTFE. By PTFE pretreatment of porous metal carrier, the ...
2007-09-01
Solar power station. Sonnenkraftwerk
Energy Technology Data Exchange (ETDEWEB)
The invention concerns a solar power station with a hollow solar heater, which has reflected radiation coming in, focussed by a mirror through the inlet opening. To match the differing solar radiation during the day, the inlet opening can be adjusted by changing its cross-section. This is done by at least two thick flat circular parts which can move relative to each other which are preferably movable relative to each other in pairs on a common rail and which are cooled by a coolant which is the working medium for absorbing solar energy.
1982-02-25
This report provides test results on the thermal performance of an Owens-Illinois Sunpak liquid, evacuated tube, solar collector under simulated conditions. The test was conducted using the Marshall Space Flight Center Solar Simulator in accordance with the test requirements specified in ASHRAE 93-77 (Method of Testing to Determine the Thermal Performance of Solar Collectors) and the procedures contained in MTCP-FA-SHAC-400 (Procedure for Operation of the MSFC Solar Simulator Facility). The tests were performed on a module used on the early demonstration projects. A current production module is undergoing tests with results to be in a subsequent report.
1979-10-10
Recent progress in a-Si solar cells
Energy Technology Data Exchange (ETDEWEB)
As concern regarding global environmental problems such as the greenhouse effect and acid rain has increased, so too has the demand for commercially viable solar cells as a clean energy source. Interest in amorphous silicon (a-Si) solar cells has been particularly high, due to their low cost. Technological developments in the field of a-Si solar cells are discussed from the viewpoints of fabrication process, materials, and cell structures. Various applications and systems that take advantage of the a-Si solar cell are then introduced. Finally, future prospects are mentioned
1997-04-14
Practical antireflection coatings for metal-semiconductor solar cells
The metal-semiconductor solar cell is a potential candidate for converting solar energy to electrical energy for space and terrestrial application. In this paper, a method for obtaining parameters of practical antireflection (AR) coatings for the metal-semiconductor solar cells is given. This method utilizes the measured equivalent index of refraction obtained from ellipsometry, since the surface to be AR coated has a multilayer structure. Both the experimental results and theoretical calculations of optical parameters for Ta/sub 2/O/sub 5/ AR coatings on Au-GaAs and Au-GaAs/sub 0.78/P/sub 0.22/ solar cells are presented for comparison. (AIP)
1976-09-01
Low temperature solar-to-electric power conversion system
An electric power generating apparatus is described, including: a solar collector; a primary thermal loop including primary thermal fluid; a cavity receiver to receive reflected solar energy from the solar reflector, convert the solar energy into thermal energy, and transmit the thermal energy to the primary thermal fluid by heating the primary thermal fluid not to exceed a given temperature, the given temperature being substantially equal to 700 F; a Stirling engine receiving the primary thermal fluid heated by the cavity receiver, including means to generate mechanical power and means to generate electrical power from the means to generate mechanical power.
1993-07-20
Historical Analysis of Investment in Solar Energy Technologies (2000-2007)
Energy Technology Data Exchange (ETDEWEB)
The solar energy industry experienced unprecedented growth in the eight years from 2000 to 2007, with explosive growth occurring in the latter half of this period. From 2004 to 2007, global private sector investment in solar energy increased by almost twenty-fold, marking a dramatic increase in the short span of four years. This paper examines the timing, magnitude, focus and location of various forms of investment in the solar energy sector. It analyzes their trends to provide an understanding of the growth of the solar industry during the past eight years and to identify emerging themes in this rapidly evolving industry.
2008-12-01
British Library Electronic Table of Contents (United Kingdom)
Nanoparticle metal oxides offer a wide variety of potential applications in medicine due to the unprecedented advances in nanobiotechnology research. In this work, the effect of zinc oxide (ZnO) nanoparticles prepared by mechano-chemical method on the antibacterial activity of different antibiotics was evaluated using disk diffusion method against Staphylococcus aureus and Escherichia coli. The average size of ZnO nanoparticles was between 20 nm and 45 nm. Although ZnO nanoparticles (500 mg/disk) decreased the antibacterial activity of amoxicillin, penicillin G, and nitrofurantoin in S. aureus, the antibacterial activity of ciprofloxacin increased in the presence of ZnO nanoparticles in both test strains. A total of 27% and 22% increase in inhibition zone areas was observed for ciprofloxac...
2010-01-01
International Nuclear Information System (INIS)
A new in vivo method has been developed for the precise observation of RES activity. Both Escherichia coli endotoxin 100 #mu#g/100 g i.v. (LPS) and radiodetoxified endotoxin 100 #mu#g/100 g body weight i.v. (RD-LPS, TOLERIN) increased the granulopectic activity of RES. The RD-LPS was more effective. The preparation containing trace elements also increased the activity of RES. The treatment consisting of the use of both trace elements and RD-LPS proved to be the most effective. The activity of RES was inversely proportional to various doses of X-ray irradiation (7, 8, 9 Gy). Trace elements and RD-LPS even improved the immunity system of animals having deteriorated RES. (N.T.).
Pinealectomy completely prevented gonadal regression as well as reduction in body weight and white adipose tissue content of the gonadal and retroperitoneal fat deposits in male meadow voles transferred from long to short day lengths. Pineal influences on pelage characteristics depended on which parameter was assessed. For instance, the increase in guard hair length observed in short-day control voles was blocked by pinealectomy; however, a similar increase in underhair length was unaffected by removal of the pineal gland. Photoperiod-dependent changes in fat deposition, testicular activity, and guard hair length presumably rely on altered pineal secretory activity to transduce the effects of day length on the neuroendocrine axis; however, mechanisms independent of pineal activity may be capable of mediating photoperiodic control of underhair growth. PMID:2979644
1988-01-01
British Library Electronic Table of Contents (United Kingdom)
The present study was designed with an aim to analyze the effect of acute aluminium phosphide (ALP) exposure (10mg/kg b.wt, intragastrically) on the kinetic characteristics of cytochrome oxidase and energy metabolism in male Wistar rat liver mitochondria. Liver mitochondrial preparations from ALP-treated rats exhibited significant decrease (66%) in the activity of cytochrome oxidase suggesting that there was a decrease in the catalytic efficiency of the active oxidase molecules on ALP treatment. The decreased activity of cytochrome oxidase with altered NADH and succinic dehydrogenase activities might have contributed towards a significant decline in state 3 and state 4 respiration as observed. These alterations in the electron transport chain complexes in turn adversely affected the ATP sy...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
The growth response, total hemocyte count (THC), respiratory burst (release of superoxide anion), phenoloxidase (PO) activity, superoxide dismutase (SOD) activity, nitric oxide synthase (NOS) activity as well as resistance to the pathogen Vibrio alginolyticus were measured in Litopenaeus vannamei, which had been fed diets supplemented with glycyrrhizin (the aqueous extract of licorice, Glycyrrhiza glabra, roots) at 0, 50, 100, 150, and 200 mg/kg of feed for 8 wk. In the feeding trial, there was no significant difference in survival rate (P > 0.05). Significant higher specific growth rate was observed in treatments with dietary glycyrrhizin than that in the control group (P < 0.05). Shrimp fed a diet with 200 mg/kg of glycyrrhizin had significant higher THC, PO activity, respiratory burst a...
2010-01-01
Solar thermal production of zinc: Program strategy
Energy Technology Data Exchange (ETDEWEB)
The solar thermal production of zinc is considered for the conversion of solar energy into storable and transportable chemical fuels. The ultimate objective is to develop a technically and economically viable technology that can produce solar zinc. The program strategy for achieving such a goal involves research on two paths: a direct path via the solar thermal splitting of ZnO in the absence of fossil fuels, and an indirect path via the solar carbothermal/CH{sub 4}-thermal reduction of Zn O, with fossil fuels (coke or natural gas) as chemical reducing agents. Both paths make use of concentrated solar energy for high-temperature process heat. The direct path brings us to the complete substitution of fossil fuels with solar fuels for a sustainable energy supply system. The indirect path creates a link between today`s fossil-fuel-based ...
1999-08-01
Design and performance of a solar-powered air-conditioning system in a green building
Energy Technology Data Exchange (ETDEWEB)
A solar-powered adsorption air-conditioning system was designed and installed in the green building of Shanghai Research Institute of Building Science. The system contained 150 m{sup 2} solar collectors and two adsorption chillers with nominal refrigeration capacity of 8.5 kW. Based on performance characteristics of the adsorption chiller, the operation mode of the solar-powered air-conditioning system was optimized by maintaining a phase shift of 540 s between the two adsorption chillers. Thereafter, the whole system realized stable operation by the balance of heat consumption and refrigeration output. From June to August of 2005, the solar-powered air-conditioning system continuously ran between 9:00 and 17:00. The operation performance of the system under representative working condition showed that the average refrigeration output of the solar-powered air-conditioning system was ...
2008-05-15
High variability in Vela X-1: giant flares and off states
We investigate the spectral and temporal behavior of the high mass X-ray binary Vela X-1 during a phase of high activity, with special focus on the observed giant flares and off states. INTEGRAL observed Vela X-1 in a long almost uninterrupted observation for two weeks in 2003 Nov/Dec. The data were analyzed with OSA 7.0 and FTOOLS 6.2. We derive the pulse period, light curves, spectra, hardness ratios, and hardness intensity diagrams, and study the eclipse. In addition to an already high activity level, Vela X-1 exhibited several intense flares, the brightest ones reaching a maximum intensity of more than 5 Crab in the 20-40 keV band and several off states where the source was no longer detected by INTEGRAL. We determine the pulse period to be 283.5320+/-0.0002 s, which is stable throughout the entire observation. Analyzing the eclipses provided an improvement ...
2008-01-01
Novel high-throughput screening system for identifying STAT3-SH2 antagonists
International Nuclear Information System (INIS)
Constitutive activation of the oncogenic transcription factor STAT3 frequently occurs in various human malignancies. STAT3 activation involves dimerization via intermolecular pTyr-SH2 interaction. Thus, antagonizing this interaction is a feasible approach to inhibit STAT3 activation for cancer therapy. In order to identify selective STAT3 inhibitors, we developed a biochemical HTS system based on AlphaScreen technology, which measures the abilities of test compounds to antagonize pTyr-SH2 interactions. We screened our chemical libraries using this system and identified 5,15-diphenylporphyrin (5,15-DPP) as a selective STAT3-SH2 antagonist. Selective inhibition of STAT3 nuclear translocation and DNA biding activity was observed in cells treated with 5,15-DPP. IL-6-dependent dimerization of STAT3, c-myc promoter binding and c-myc protein expression were all suppressed by 5,15-DPP, ...
2009-03-13
Energy Technology Data Exchange (ETDEWEB)
2,6-Dinitrotoluene (2,6-DNT) and pentachlorophenol (PCP) are used for industrial purposes and are found in the environment as hazardous contaminants. Because concurrent exposure to both compounds can occur, it is of interest to determine if organochlorine compounds potentiate the effect of nitroaromatic chemicals. A significant increase in mutagenicity was observed in urines from mice treated with 2,6-DNT alone and in combination with PCP. By week 4, mice that received both 2,6-DNT and PCP excreted urine that was more mutagenic than that from animals which received only 2,6-DNT. At weeks 2 and 4, mice were sacrificed and intestinal enzyme activities (nitroreductase, azo reductase, {beta}-glucuronidase, dechlorinase, and dehydrochlorinase) were quantitated. The enhanced genotoxicity observed in urines from 2,6-DNT/PCP-treated mice coincided with a decrease in nitroreductase and an increase in {beta}-glucuronidase ...
1991-01-01
Change in pore structure of coals by activation with KOH; KOH fukatsushita sekitan no saiko kozo
Energy Technology Data Exchange (ETDEWEB)
Three typical Japanese coals of non-coking coal, coking coal and anthracite were heat-treated with KOH, and change in their pore structure was examined by absorption of N2, X-ray diffraction and TEM observation. In addition, the relation between a coal rank and pore structure was also studied by absorption experiment of N2. In experiment, the mixture of coal and KOH in a nickel holder was heat-treated in N2 gas flow at heating rate of 2{degree}C/min, and held at a fixed temperature for one hour. To clarify the pore structure, N2 absorption isotherms were measured at -196{degree}C under nearly 76cmHg using a commercially available full-automatic absorption measurement equipment. Based on the X-ray diffraction and TEM observation results on activated coals, the relation between the N2 absorption and pore structure was studied. The results are summarized as follows: (1) The yield and absorption ability of coals increase with a ...
1996-10-28
Energy Technology Data Exchange (ETDEWEB)
The elastic behaviour of YBaCuO specimens has been studied by very low-frequency isothermal internal-friction measurements. A relaxation peak is observed which is attributed to oxygen atom jumps, between A(1/2 0 0) and B(0 1/2 0) sites, in the CuO planes of the orthorhombic phase. A limit relaxation time {tau}{sub 0}, 2.6 {center dot} 10{sup -15}s, and an activation energy, 1.3eV, have been obtained from the shift of the maximum damping frequency observed when the measurement temperature is changed. The proposed values for the limit relaxation time and the activation energy are in good agreement with those previously proposed in the literature.
1992-02-07
Point defect supersaturation and enhanced diffusion in SPE regrown silicon
Energy Technology Data Exchange (ETDEWEB)
Transient, greatly enhanced diffusion has been observed on annealing solid-phase-epitaxial (SPE) grown Si-Sb alloys. This is shown to be due to a high concentration of interstitials being trapped during SPE regrowth. The migration enthalpy, for diffusion of Sb by an interstitialcy mechanism was measured as 1.8 +/- 0.2 eV. The interstitials eventually condensed into loops, marking the end of the transient. In a SPE grown Si-Bi alloy a similar transient enhanced diffusion was observed, with an activation energy of 2.0 +/- 0.2 eV, but no loops formed. 8 figures, 7 references.
1984-01-01
Point defect supersaturation and enhanced diffusion in SPE regrown silicon
International Nuclear Information System (INIS)
Transient, greatly enhanced diffusion has been observed on annealing solid-phase-epitaxial (SPE) grown Si-Sb alloys. This is shown to be due to a high concentration of interstitials being trapped during SPE regrowth. The migration enthalpy, for diffusion of Sb by an interstitialcy mechanism was measured as 1.8 +/- 0.2 eV. The interstitials eventually condensed into loops, marking the end of the transient. In a SPE grown Si-Bi alloy a similar transient enhanced diffusion was observed, with an activation energy of 2.0 +/- 0.2 eV, but no loops formed. 8 figures, 7 references.
Energy Technology Data Exchange (ETDEWEB)
The article provides a 1998 updated picture of Italy's and the world's photovoltaic market in terms of produced modules and total installed capacity, as well as market growth forecasts up to 2010. After a short description of the state-of-the-art of cell and module manufacturing, ana analysis of the cost of producing a photovoltaic kw is reported for different plant types: stand-alone plants with energy storage batteries, plants connected to low low voltage networks or intended for supporting medium voltage networks, hybrid plants with diesel sets. The article is concluded by illustrating ENEL's (Electric Power Production Company) engagement in the field of photovoltaic solar energy as regards theoretical studies, research and testing of new technologies, and installing plants; over nearly twenty years of activity, ENEL has designed and built a few hundreds of photovoltaic plants for a total capacity of about 4.000 ...
1999-04-01
Energy Technology Data Exchange (ETDEWEB)
The in vivo toxic effects of hexavalent chromium (20 mg/liter) on hemolymph glucose, tissue glycogen, total free sugars, and active and total phosphorylases of an edible, freshwater crab Barytelphusa guerini were studied. In a 15-day exposure span followed by a 15-day postexposure recovery, the time-course alterations in these constituent segments of the glycogen metabolism indicate an inconsistent depletion in metabolite levels and elevated enzyme activities during exposure period as well as hyperglycemia. An insignificant recovery was observed in these parameters on the 15th day of the postexposure phase.
1990-08-01
British Library Electronic Table of Contents (United Kingdom)
An experimental investigation on the thermal decomposition of CH4 into C and H2 was carried out using a 5kW particle-flow solar chemical reactor tested in a solar furnace in the 1300-1600K range. The reactor features a continuous flow of CH4 laden with mm-sized carbon black particles, confined to a cavity receiver and directly exposed to concentrated solar irradiation of up to 1720 suns. The reactor performance was examined for varying operational parameters, namely the solar power input, seed particle volume fraction, gas volume flow rate, and CH4 molar concentration. Methane conversion and hydrogen yield exceeding 95% were obtained at residence times of less than 2.0s. A solar-to-chemical energy conversion efficiency of 16% was experimentally reached, and a maximum value of 31% was numer...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
This research report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the feasibility of setting up 'MINERGIE' low-energy-consumption module standards for the production of heat in small residential buildings. The aims of the standards and the basic idea behind the MINERGIE-modules are discussed. The concepts of the modules for heat pumps and wood-fired heating systems and their combination with solar installations are examined, as are their areas of application. The requirements placed on the modules are listed. System concepts, including simple schematics for typical installations, are presented for wood-log, wood-chippings and pellets-fired systems as well as for ground-loop and air-water heat pump systems as well as their solar-aided counterparts. The results of cost-benefit analyses are presented and questions regarding system guarantee and liability are examined.
2005-07-01
Laser beam apparatus and method for analyzing solar cells
Energy Technology Data Exchange (ETDEWEB)
A laser beam apparatus and method for analyzing, inter alia, the current versus voltage curve at the point of illumination on a solar cell and the open circuit voltage of a solar cell. The apparatus incorporates a lock-in amplifier, and a laser beam light chopper which permits the measurement of the AC current of the solar cell at an applied DC voltage at the position on the solar cell where the cell is illuminated and a feedback scheme which permits the direct scanning measurements of the open circuit voltage. The accuracy of the measurement is a function of the intensity and wavelength of the laser light with respect to the intensity and wavelength distribution of sunlight and the percentage the dark current is at the open circuit voltage to the short circuit current of the solar cell.
1980-01-01
British Library Electronic Table of Contents (United Kingdom)
This study addresses the solar thermal decomposition of natural gas for the co-production of hydrogen, as well as Carbon Black as a high-value nano-material, with the bonus of zero CO2 emissions. The work focused on the development of a medium-scale solar reactor (10kW) based on the concept of indirect heating. The solar reactor is composed of a cubic cavity receiver (20cm side), which absorbs concentrated solar irradiation through a quartz window via a 9cm-diameter aperture. The reacting gas flows inside four graphite tubular reaction zones that are settled vertically inside the cavity. Experimental results were as follows: methane conversion and hydrogen yield of up to 98% and 90%, respectively, were achieved at 1770K, and acetylene was the most important by-product, with a mole fraction...
2009-01-01
The Magdalena Ridge Observatory 2.4 m Telescope
EOS Technologies has been commissioned to design and build a unique 2.4m astronomical telescope for the Magdalena Ridge Observatory. This telescope utilizes a high quality primary mirror and cell from a now decommissioned military application. This paper describes the project and gives an overview of the telescope design. The Magdalena Ridge Observatory (MRO) 2.4 meter telescope will be primarily utilized to observe, track, and characterize solar system astronomical targets, Earth satellites, space vehicles, and terrestrial military targets. The telescope's rapid tracking (slew rates are 10o/sec) will allow it to move to any target and acquire data within one minute of receipt of notice. In this way, the telescope will be used to capitalize on targets of opportunity that occur in asteroid studies (e.g., Near Earth Objects) and in astrophysics, such as gamma ray bursts and other transient phenomena. Planned instrumentation includes a CCD imager, ...
2006-07-01
The Effect of Lunar-like Satellites on the Orbital Infrared Light Curves of Earth-analog Planets
We investigate the influence of lunar-like satellites on the infrared orbital light curves of Earth-analog extra-solar planets. Such light curves will be obtained by NASA's Terrestrial Planet Finder (TPF) and ESA's Darwin missions as a consequence of repeat observations to confirm the companion status of a putative planet. We use an energy balance model to calculate disk-averaged infrared (bolometric) fluxes from planet-satellite systems over a full orbital period (one year). The satellites are assumed to lack an atmosphere, have a low thermal inertia like that of the Moon and span a range of plausible radii. The planets are assumed to have thermal and orbital properties that mimic those of the Earth while their obliquities and orbital longitudes of inferior conjunction remain free parameters. Even if the gross thermal properties of the planet can be independently constrained (e.g. via spectroscopy or visible-wavelength detection of specular ...
2008-01-01
We present metallicity estimates for seven open clusters based on spectrophotometric indices from moderate-resolution spectroscopy. Observations of field giants of known metallicity provide a correlation between the spectroscopic indices and the metallicity of open cluster giants. We use \\chi^2 analysis to fit the relation of spectrophotometric indices to metallicity in field giants. The resulting function allows an estimate of the target-cluster giants' metallicities with an error in the method of \\pm0.08 dex. We derive the following metallicities for the seven open clusters: NGC 1245, [m/H]=-0.14\\pm0.04; NGC 2099, [m/H]=+0.05\\pm0.05; NGC 2324, [m/H]=-0.06\\pm0.04; NGC 2539, [m/H]=-0.04\\pm0.03; NGC 2682 (M67), [m/H]=-0.05\\pm0.02; NGC 6705, [m/H]=+0.14\\pm0.08; NGC 6819, [m/H]=-0.07\\pm0.12. These metallicity estimates will be useful in planning future extra-solar planet transit searches since planets may form more readily in metal-rich ...
2005-01-01
Outdoor air quality and health effects : a case study
Energy Technology Data Exchange (ETDEWEB)
This paper presents the results of a study carried out at three sites in Madurai, India in order to assess ambient air quality levels and their impact on public health in urban areas. Indicators of public health were sought through primary and secondary health data and blood lead concentrations of male and female inhabitants and shopkeepers. Lean concentrations in blood samples were examined according to distance from the road, age, smoking status, hours of stay per day in the city, and period of stay in years in Madurai. Ambient air quality level indicators included the level of gaseous and particulate pollution using Central Pollution Control Board standard estimation methods. Observed atmospheric conditions across the three sites are examined according to mean solar insolation, mean temperature, mean relative humidity and mean wind velocity. The study concluded that pollution abatement measures must be implemented to safeguard public health ...
2005-07-01
Energy Technology Data Exchange (ETDEWEB)
Glacier fluctuations exclusively due to internal variations in the climate system are simulated using downscaled integrations of the ECHAM4/OPYC coupled general circulation model (GCM). A process-based modeling approach using a mass balance model of intermediate complexity and a dynamic ice flow model considering simple shearing flow and sliding are applied. Multi-millennia records of glacier length fluctuations for Nigardsbreen (Norway) and Rhonegletscher (Switzerland) are simulated using auto-regressive processes determined by statistically downscaled GCM experiments. Return periods and probabilities of specific glacier length changes using GCM integrations excluding external forcings such as solar irradiation changes, volcanic or anthropogenic effects are analyzed and compared to historical glacier length records. Preindustrial fluctuations of the glaciers as far as observed or reconstructed, including their advance during the ...
2001-08-01
Designing Surveys for Tests of Gravity
Modified gravity theories may provide an alternative to dark energy to explain cosmic acceleration. We argue that the observational program developed to test dark energy needs to be augmented to capture new tests of gravity on astrophysical scales. Several distinct signatures of gravity theories exist outside the linear regime, especially owing to the screening mechanism that operates inside halos like the Milky Way to ensure that gravity tests in the solar system are satisfied. This opens up several decades in length scale and new classes of galaxies at low-redshift that can be exploited by surveys. While theoretical work on models of gravity is in the early stages, we can already identify new regimes which cosmological surveys could target to test gravity. These include: 1. A small scale component that focuses on the interior and vicinity of galaxy and cluster halos. 2. Spectroscopy of low redshift galaxies, especially galaxies smaller than ...
2011-01-01
Upper Limits from HESS Observations of AGN in 2005-2007
Very high energy (VHE; >100 GeV) observations of a sample of selected active galactic nuclei (AGN) were performed between January 2005 and April 2007 with the High Energy Stereoscopic System (HESS), an array of imaging atmospheric-Cherenkov telescopes. Significant detections are reported elsewhere for many of these objects. Here, integral flux upper limits for twelve candidate very high energy (VHE; >100 GeV) gamma-ray emitters are presented. In addition, results from HESS observations of four known VHE-bright AGN are given although no significant signal is measured. For three of these AGN (1ES 1101-232, 1ES 1218+304, and Mkn 501) simultaneous data were taken with the Suzaku X-ray satellite.
2007-01-01
Strong coupled organic microcavities
International Nuclear Information System (INIS)
Strong coupled organic-inorganic microcavities device has been realized and studied. One of the two cavities contains an organic thin film of tetrakis(4-methoxyphenyl)porphyrin, whereas the other microcavity is a dielectric structure coupled to the organic one by means of a LiF/ZnS Bragg mirror. Reflectivity spectra show the presence of two well defined cavity dips. We observe an energy splitting of the two cavity-modes. Despite only one cavity contains the active layer, the photoluminescence spectra display two peaks at the same energy of the reflectivity dips. These observations indicate the strong coupling of the two cavities. The comparison of the diagonalized effective Hamiltonian with the observed resonances further confirms the strong coupling.
2010-02-01
Energy Technology Data Exchange (ETDEWEB)
The programme 'Solarthermie 2000' aimed at the testing and optimization of active solar systems, especially for service water heating. Sub-programme 2 was to provide the technical fundamentals and achieve a certain degree of standardization in order to make the technology economically competitive. This necessitated long-term monitoring of a representative number of systems. [German] Im Rahmen des Foerder- und Demonstrationsprogramms Solarthermie 2000, Teilprogramm 2 erfolgt durch die Foerderung von bis zu 100 solarthermischer Anlagen mit Schwerpunkt in den neuen Bundeslaendern eine umfassende Erprobung und Optimierung von Systemen zur aktiven thermischen Sonnenenergienutzung vorwiegend zur Brauchwassererwaermung. Mit dem Teilprogramm 2 sollen die technischen Voraussetzungen fuer einen kuenftigen wirksamen Beitrag der Solarthermie zur Energieversorgung geschaffen und durch Systemstandardisierung die wirtschaftliche ...
2000-07-01
Genotoxic effects of sunlight-activated waste waters
Energy Technology Data Exchange (ETDEWEB)
Natural sunlight induces a genotoxic response in cultured CHO cells pre-treated with shale oil retort process water. Near ultraviolet light (NUV) component of the solar spectrum is the apparent radiation responsible for photoactivation. Cultured human skin fibroblasts are acutely sensitive to the genotoxic effects of photoactivated process water. The mutagenic potential of photoactivated process water in human cells is the same as that witnessed for an equivalent killing dose of the potent skin carcinogen FUV. DNA repair processes are involved in modulating genotoxic effects of this photo-induced process. The exact magnitude of the potential health-related and environmental risks resulting from photoactivation of retort process waters and other oil shale by-products is unassessed at this time. Our demonstration that a significant rate of mutation occurs in cultured human cells exposed to high dilutions of process waters and fluences of NUV comparable to that ...
1981-01-01
The influence of chlorine on the fate and activity of alkali metals during the gasification of wood
Energy Technology Data Exchange (ETDEWEB)
Chlorine clearly inhibits the CO{sub 2}-gasification reaction of charcoal at 800{sup o}C. From this and other observations the picture emerges that the reduction in the gasification reactivity of the charcoal is intimately related to the deactivation of the catalytically active alkali metals residing in the wood due to the formation of the chloride salt. It is argued that the heavy metal chlorides will likely transfer the chlorine to the indigenous alkali metals during the pyrolysis stage of the wood. The fate of the thus formed alkali metal chlorides can then be either their removal from the sample (evaporation), or, when present at the gasification stage, re-activation (i.e., de-chlorination) under our gasification conditions. (author) 3 figs., 4 refs.
1999-08-01
The effect of excimer laser pretreatment on diffusion and activation of boron implanted in silicon
International Nuclear Information System (INIS)
We have investigated the effect of excimer laser annealing (ELA) on transient enhanced diffusion (TED) and activation of boron implanted in Si during subsequent rapid thermal annealing (RTA). It is observed that ELA with partial melting of the implanted region causes reduction of TED in the region that remains solid during ELA, where the diffusion length of boron is reduced by a factor of #approx#4 as compared to the as-implanted sample. This is attributed to several mechanisms such as liquid-state annealing of a fraction of the implantation induced defects, introduction of excess vacancies during ELA, and solid-state annealing of the defects beyond the maximum melting depth by the heat wave propagating into the Si wafer. The ELA pretreatment provides a substantially improved electrical activation of boron during subsequent RTA.
2005-11-07
Spin dynamics in Ho{sub 2}Ru{sub 2}O{sub 7}
Energy Technology Data Exchange (ETDEWEB)
The spin relaxation processes within the pyrochlore Ho{sub 2}Ru{sub 2}O{sub 7} have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy {delta} = (329 {+-} 6) K and characteristic relaxation time {tau}{sub 0} (5.2 {+-} 0.3) x 10{sup -12} s in the paramagnetic state, akin to those found in the spin ice, Ho{sub 2}Ti{sub 2}O{sub 7}. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.
2005-11-09
International Nuclear Information System (INIS)
The spin relaxation processes within the pyrochlore Ho_2Ru_2O_7 have been investigated by neutron scattering and bulk property techniques. A single-ion process, that is thermally activated, dominates the spin-spin relaxation spectrum above 2 K. Assuming Arrhenius behaviour, we found an activation energy #DELTA# = (329 #+-# 6) K and characteristic relaxation time #tau#_0 (5.2 #+-# 0.3) x 10"-"1"2 s in the paramagnetic state, akin to those found in the spin ice, Ho_2Ti_2O_7. Atlow temperature (T<95 K) the activation energy lowers and below 20 K the entropy and ac susceptibility are similar to that observed in other spin ice compounds within a 10 kOe field.
2005-11-09
Multi walled carbon nanotubes/epilson polylysine nanocomposite with enhanced antibacterial activity
British Library Electronic Table of Contents (United Kingdom)
Abstract Aims: To develop a new nano composite of multi walled carbon nanotubes (MWNTs) with enhanced antimicrobial activity. Methods and Results: A novel antimicrobial nanocomposite [MWNT epilson polylysine (MEPs)] was synthesized via covalent attachment of epilson polylysine on MWNTs with hexamethylene diisocyanate (HDI) as the coupling agent. UV visible spectra and Fourier transform infrared spectra (FT IR) investigations indicate that MEPs is stable, with epilson polylysine leaching effectively eliminated. When compared to MWNTs, the new nano composite MEPs exhibits enhanced antimicrobial activities. In 20 mg l 1 suspensions, significant increases of 72 1, 64 5 and 69% against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus can be observed. The deposited film of MEPs...
2011-01-01
High temperature deformation behaviour of Ti-10V Alloy and associated activation energy
International Nuclear Information System (INIS)
High temperature deformation behaviour of an experimental Beta-titanium alloy Ti-10V has been studied in the temperature range 800 to 945 degree C by using the method of crosshead speed cycling. Although subgrain formation was observed but the alloy did not exhibit superplastic behaviour in the entire temperature range studied. A very large initial grain size and elongation of grains during the deformation are considered the main factors responsible for absence of superplastic behaviour. The activation energy values for regions II and III of the ln sigma vs. ln small epsilon plots are close to the lower of the two activation energy values proposed together to describe self diffusion in beta-phase suggesting that the rate controlling mechanism is that for lattice diffusion rather then grain boundary diffusion. (author)
2004-06-01
Glutathione peroxidase activity in the selenium-treated alga Scenedesmus quadricauda
British Library Electronic Table of Contents (United Kingdom)
The function of selenium in an organism is mediated mostly by selenoproteins including glutathione peroxidase. Glutathione peroxidase is a potent anti-oxidative enzyme, scavenging a variety of peroxides. The green alga Scenedesmus quadricauda was used to investigate the relationship between the toxicity of selenium and the glutathione peroxidase activity. Selenium resistant strains SeIV and SeVI were synchronized and grown in high concentrations of Se (selenite or selenate). As a measure of selenium toxicity the EC50 values were determined. During growth of the untreated wild type, glutathione peroxidase activity increased slightly and then declined gradually until the end of the cell cycle. A similar pattern was observed in untreated resistant strains and when resistant strains were grown...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
From their genesis by weathering and sedimentation, bauxites, the principal aluminium ores, contain appreciable amounts of uranium and thorium. High resolution gamma spectrometry with a high purity germanium detector was used for an analysis of four industrially used bauxites from Gondama, Sierra Leone; Boke, Guinea; Weipa, Queensland, Australia; Gove, Northern Territory, Australia. Significant differences in uranium to thorium ratios and in activities of the uranium and thorium daughters were observed for the four bauxites. It was found that the bauxite from Gondama, Sierra Leone has an activity of only 10% compared with the others. Red mud tailings from such a bauxite may well be used as an additive to bricks, which is now illegal for normal red mud from more active bauxites. (author).
1992-01-01
International Nuclear Information System (INIS)
From their genesis by weathering and sedimentation, bauxites, the principal aluminium ores, contain appreciable amounts of uranium and thorium. High resolution gamma spectrometry with a high purity germanium detector was used for an analysis of four industrially used bauxites from Gondama, Sierra Leone; Boke, Guinea; Weipa, Queensland, Australia; Gove, Northern Territory, Australia. Significant differences in uranium to thorium ratios and in activities of the uranium and thorium daughters were observed for the four bauxites. It was found that the bauxite from Gondama, Sierra Leone has an activity of only 10% compared with the others. Red mud tailings from such a bauxite may well be used as an additive to bricks, which is now illegal for normal red mud from more active bauxites. (author).
British Library Electronic Table of Contents (United Kingdom)
Nitric oxide (NO) is a gas produced through the action of nitric oxide synthase that acts as a neurotransmitter in the central nervous system (CNS) of adult gastropod mollusks. There are no known reports of the presence of NOS-containing neurons and glial cells in young and adult Megalobulimus abbreviatus. Therefore, NADPH-d histochemistry was employed to map the nitrergic distribution in the CNS of young and adult snails in an attempt to identify any transient enzymatic activity in the developing CNS. Reaction was observed in neurons and fibers in all CNS ganglia of both age groups, but in the pedal and cerebral ganglia, positive neurons were more intense than in other ganglia, forming clusters symmetrically located in both paired ganglia. However, neuronal NADPH-d activity in the mesocer...
2010-01-01
International Nuclear Information System (INIS)
The activity of tyrosine aminotransferase (TAT) in the liver of mice subjected simultaneously to ionizing radiation and to local inflammatory process showed in the first 24 hours of the experiment statistically significant changes resulting from summation of the harmful effects of both factors. In the second 24-hour period an evident tendency was observed for return of a normal circadian rhythm of the enzyme. This points to presence of an endogenous mechanism of suppression of the manifestations of significant desynchronization of the circadian rhythm. The paper contains also a trial of mathematical analysis of changes in TAT activity in the circadian rhythm, a description and analysis or the suppression process, qualitative and quantitative determination of the phenomenon of cumulation of the effects of powerful stress factors acting on the animal organism. The obtained results were compared with the results of ...
1980-01-01
British Library Electronic Table of Contents (United Kingdom)
Measurement of serum biochemical parameters in response to metal exposures can be especially useful to help identify target organs of toxicity as well as the general health status of animals. Oreochromis niloticus were exposed to 5.0?mg/L?Zn, 1.0?mg/L?Cd, and 5.0?mg/L?Zn?+?1.0?mg/L?Cd mixture for 7 and 28?days, and alterations in serum enzyme activities and ion levels were measured. Significant changes in all the biochemical parameters were found to be time dependent. Following metal exposure, alkaline phosphatase activity was elevated at both exposure periods. No changes in activities of lactate dehydrogenase and lipase were observed in response to single or combined Zn and Cd exposure at 7?days while they increased at 28?days. Fish exposed to metals showed a decrease in cholinesterase ac...
2010-01-01
Basic research of the structure and electronic properties of a-Si:H is reported with particular emphasis on the role of defects. The main findings are as follows: (1) low defect density material can be deposited at a high rate using SiH/sub 4/ diluted in He or Ne. Using Ar or Kr results in a high defect density and columnar material; (2) an electrical bias during deposition modifies the band gap, hydrogen concentration and structure; (3) the clustering of hydrogen in the regions between the columns is confirmed; (4) hydrogen diffusion is observed by NMR; (5) the oxidation of an a-Si:H surface results in approx. 3 x 10/sup 11/ cm/sup -2/ dangling bonds at the interface; (6) auger recombination of photoexcited carriers is a significant non-radiative mechanism at low temperatures; (7) non-radiative recombination by diffusion and capture at dangling bonds is observed at temperatures above 50 to 100/sup 0/K; (8) the defect density in doped and ...
1981-08-01
WIRE-SPEC-003 Wide-Field Infrared Explorer ... - sunland - NASA
Oct 20, 1997 ... The following requirements apply to the solar array: ..... housings will be coated with material meeting the program's outgassing requirements. ... The solar array temperature testing requirements will be determined by analysis. .... The ADS also generates attitude products for the project and science team. ...
Thermal energy considerations on solar cavity wall building
Energy Technology Data Exchange (ETDEWEB)
The dwelling is equipped with solar collectors which heat the air circulating in the cavity walls and the space beneath the floors. The thermal aspects of such a building are described. Heat balance, losses, heating by the sun in different seasons are described. Different measures taken to reduce the energy losses are described.
1983-02-01
Energy Technology Data Exchange (ETDEWEB)
A discussion is given in a popular manner of the solar powered aircraft Solair I. The achievements of the designer are detailed, and trial runs leading up to the first successful flight are given. Technical data of Solair I are listed, and brief news items about it are presented.
1983-03-01
Telephone, mail, and personal questionnaires for data collection. [For heating and cooling
Energy Technology Data Exchange (ETDEWEB)
Forms used in conducting a national survey about solar energy are presented. Forms for representatives from the domestic, commercial, and industrial sectors, owners and non-owners of solar equipment, are shown. Participants were to be contacted by telephone, mail, and personal visits. (MCW)
1980-02-20
Synchronous orbit performance of Hughes Aircraft Company solar arrays - update
Energy Technology Data Exchange (ETDEWEB)
The synchronous orbit performance of Hughes Aircraft Company solar arrays is presented and compared with the results of ground based predictions for orbital durations of almost 11 years. Performances of the Intelsat IV*, IVA*, and Telesat (Anik) solar arrays are detailed. This paper is an update of the in-orbit performances previously reported in 1976 (1). The in-space performance data indicate solar array power degradation of 16.7 percent for Intelsat IV F-2 after 130 months in orbit, and 13.0 percent for Telesat F-1 after 85 months in orbit. The predicted output of each of these solar arrays is within 2 percent of the actual in-orbit performance of these systems. The Intelsat IV F-2 experienced the 4 August 1972 solar flare. The ability to accurately predict the performance of solar arrays within telemetry accuracy is demonstrated. This ability combines the ...
1982-08-01
Some design considerations for solar-powered aircraft
Energy Technology Data Exchange (ETDEWEB)
Performance and operating characteristics are presented for a solar powered aircraft intended to remain aloft for long periods. The critical technologies which limit the performance are identified. By using the techniques presented, the effects of variation in the system parameters are studied. Practical design consideration are discussed.
1980-06-01
Solar System Test Kit Baldwin 3rd grade - Night Sky Network
Astronomical Society of Northern New England: Solar System Test Kit Baldwin 3rd grade Astronomical Society of Northern New England ...
Energy Technology Data Exchange (ETDEWEB)
A brief overview of the conceptual design of a solar central receiver system integrated with an existing cogeneration facility is provided. A synopsis of the performance and economic evaluation, and an assessment of the concept from the site owner's perspective are given.
1981-08-07
SUN WORSHIPER: McCready's Solar Challenger flies over the English Channel
Energy Technology Data Exchange (ETDEWEB)
The background for the project of a solar-powered aircraft, designed and built by Dr. Paul McCready of California, is reported with details on the aircraft design and its flight across the English Channel.
1983-12-01
Energy Technology Data Exchange (ETDEWEB)
Conference paper regarding research in freeze-protection methods that could extend market acceptance for passive solar domestic water heating systems in more northern climates if the U.S.
2006-05-01
NREL: News Feature - Solar and Hydrogen Car Races Spark Imaginations
car running down the track." Choosing to focus on the design of a hydrogen fuel cell model car rather than a solar race car was a deliberate decision for team, "Larry the...
2011-08-27
NREL preprints for the 23rd IEEE Photovoltaic Specialists Conference
Energy Technology Data Exchange (ETDEWEB)
Topics covered include various aspects of solar cell fabrication and performance. Aluminium-gallium arsenides, cadmium telluride, amorphous silicon, and copper-indium-gallium selenides are all characterized in their applicability in solar cells.
1993-05-01
Method of restoring degraded solar cells
Energy Technology Data Exchange (ETDEWEB)
Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200.degree. C. for at least 30 minutes restores their efficiency.
1983-01-01
Laser-assisted solar-cell metallization processing
Energy Technology Data Exchange (ETDEWEB)
Laser assisted solar cell metallization processing which is a one step process is examined. The potential advantages of laser disposition techniques for photovoltaic systems are: a high resolution, no photolithography, clean and contamination free, in-situ sintering, and low contact resistance.
1984-03-01
Laser-assisted solar cell metallization processing. Quarterly Report, December 1984-February 1985
Energy Technology Data Exchange (ETDEWEB)
Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are being investigated, developed, and characterized. The tasks comprising these investigations are outlined.
1985-04-01
The applicability of isothermal solidification as a contacting method for solar cells was proved for the systems AgSn and AuIn. The process is advantageous in that it requires no fluxes, no inert gases, and no pretreatment of the components. The IE contac...
1993-01-01
High-Speed Ultrahigh-Resolution Optical Coherence Tomography Findings in Chronic Solar Retinopathy
UK PubMed Central (United Kingdom)
PurposeTo describe ocular findings for a 34-year-old man with chronic solar retinopathy using high-speed ultrahigh-resolution (UHR) optical coherence tomography (OCT).Full Text Available
2008-01-01
High Efficiency Thin-Fili, GaAs Solar Cells - NASA Technical ...
Metal-Semiconductor Solar Cells," J. Appl. Phys. 46,. 1286 (1975). 12) H. B. Kim , G. G. Sweeney and I. S. Heng, "Analysis of ...
High Efficiency Solar Cell on Low Cost Metal Foil Substrate
During Phase II multi-junction solar cell will be grown on the large grain thin film produced during Phase I on flexible/low cost metal foil substrate. ...
Energy Technology Data Exchange (ETDEWEB)
The purpose of this solar energy project was to design, manufacture, install, maintain and evaluate solar heating systems in order to stimulate community acceptance of the practicality of solar applications, reduce non-renewable energy resource consumption, and decrease residential expenditures for energy. The project also provided skill training and experience for CETA employees in the design, manufacture, and installation of solar energy equipment systems. CDC's contract had four separate solar energy projects; namely: Domestic Water Heating Systems for four Single-Family Homes; Domestic Water Heating for an industrial building; Domestic Water Heating for a (4) unit apartment complex (includes (12) supplemental space heating units); and Integral Passive Water Heaters and Energy Conservation Devices for (8) one bedroom homes. CDC staff designed all ...
1983-10-19
Development and Evaluation of a Reflective Solar Disinfection Pouch for Treatment of Drinking Water
UK PubMed Central (United Kingdom)
A second-generation solar disinfection (SODIS) system (pouch) was constructed from food-grade, commercially available packaging materials selected to fully transmit and amplify the antimicrobial properties...Full Text Available
2004-04-01
Calibration of the solar UV radiometers in Finland
Energy Technology Data Exchange (ETDEWEB)
In this report, the main emphasis is given to (1) the problems associated with the basic calibration of the spectroradiometer and (2) the year-to-year variability of the calibrations of the solar UV network radiometers. Also, the results from intercomparisons of the Brewer and OL 742 spectroradiometers are included
1996-12-31
5 - NASA Technical Reports Server
The mission includes a reflected solar instrument retrieving at-sensor .... incoming solar radiation. This direct aerosol radiative forcing (DARF) ... examining the behavior of geosynchronous rocket bodies and non-stabilized payloads as ...
2005 NASA Executive Capability Roadmap Report
ADVANCED MODELING, S IMULATION, AND ANALYSIS (ROADMAP 14). ...... Metal/Silicon Extraction from Regolith & manufacturing ..... addresses solar power, energy storage (in conjunction with solar power and as a prime source of ...
Extratropical Forcing of Convectively Coupled Kelvin Waves during Austral Winter.
Observations are presented that link extratropical Rossby wave disturbances excited in the Southern Hemisphere subtropical jet to the initiation of convectively coupled Kelvin waves in the Pacific intertropical convergence zone (ITCZ) during austral winter. A baroclinic, zonal wavenumber 6, eastward-propagating Rossby wave train in the subtropical jet turns northeastward in the vicinity of Australia, inducing upper tropospheric divergence and vertical motion fields that spread equatorward and induce cloudiness anomalies in the Tropics. Lower tropospheric pressure surges excited from the extratropics also induce Kelvin wave-like geopotential height and temperature anomalies at the surface, providing additional lower tropospheric convergence and vertical motion forcing. The tropical outgoing longwave radiation (OLR) and circulation fields propagate eastward in tandem with the extratropical Rossby wave train at approximately 17 m s-1. Kelvin wave ...
2003-02-01
Regulation of starch synthesis in potato tubers
Energy Technology Data Exchange (ETDEWEB)
Following tuber excision from the mother plant sucrose synthase activity fell from 3,120 to 960 nmol/g.f. wt./h within 7 days and starch synthesis ({sup 14}C sucrose incorporated into isolated discs) from 23 to 7 nmol/g.f. wt./h. While the maximum catalytic activity of sucrose synthase was more than sufficient to account for the observed rate of starch synthesis a maximum of 27% of sucrose incorporated by discs was converted into starch within 3 h. This compared with 80% conversion of {sup 14}C glucose incorporated. Tuber excision also reduced the rate of starch biosynthesis with glucose as a substrate (from 206 to 64 nmol/g.f. wt./h). The activities of UDPG-pyrophosphorylase, PPi-PFK, ATP-PFK, starch synthase and hexokinase (glucose or fructose substrates) were unaffected by tuber removal. ADPG pyrophosphorylase activity was reduced from 8,000 to 4,500 nmol/g.f. wt./h. Preliminary ...
1990-05-01
Morusin induces apoptosis and suppresses NF-#kappa#B activity in human colorectal cancer HT-29 cells
International Nuclear Information System (INIS)
Morusin is a pure compound isolated from root bark of Morusaustralis (Moraceae). In this study, we demonstrated that morusin significantly inhibited the growth and clonogenicity of human colorectal cancer HT-29 cells. Apoptosis induced by morusin was characterized by accumulation of cells at the sub-G_1 phase, fragmentation of DNA, and condensation of chromatin. Morusin also inhibited the phosphorylation of IKK-#alpha#, IKK-#beta# and I#kappa#B-#alpha#, increased expression of I#kappa#B-#alpha#, and suppressed nuclear translocation of NF-#kappa#B and its DNA binding activity. Dephosphorylation of NF-#kappa#B upstream regulators PI3K, Akt and PDK1 was also displayed. In addition, activation of caspase-8, change of mitochondrial membrane potential, release of cytochrome c and Smac/DIABLO, and activation of caspase-9 and -3 were observed at the early time point. Downregulation in the expression of Ku70 and ...
2008-07-18
International Nuclear Information System (INIS)
The efficacy of gamma irradiation as a method of decontamination for food and herbal materials is well established. In the present study, Glycyrrhiza glabra roots were irradiated at doses 5, 10, 15, 20 and 25 kGy in a cobalt-60 irradiator. The irradiated and un-irradiated control samples were evaluated for phenolic contents, antimicrobial activities and DPPH scavenging properties. The result of the present study showed that radiation treatment up to 20 kGy does not affect the antifungal and antibacterial activity of the plant. While sample irradiated at 25 kGy does showed changes in the antibacterial activity against some selected pathogens. No significant differences in the phenolic contents were observed for control and samples irradiated at 5, 10 and 15 kGy radiation doses. However, phenolic contents increased in samples treated with 20 and 25 kGy doses. The DPPH scavenging ...
2010-04-01
cookers can reach in a specified period of time. The students will also look at solar pasteurization of water and learn how the sun can ...
United States Gypsum Plant Solar Retrofit Program
Energy Technology Data Exchange (ETDEWEB)
A conceptual design of a solar retrofit to US Gypsum's plant at Sweetwater, Texas, has been developed which provides heated air to a large gypsum board drying kiln that is currently under construction. The solar heated air displaces natural gas normally used for the process heat. The solar retrofit is composed of a tower focus collector with a cavity receiver which uses air as the heat transfer fluid. An executive summary of the conceptual design, system performance, economics, and development plan is presented. (WHK)
1980-07-01
Transient behaviour of solar heated radiation receivers for small gas turbine power plants
Energy Technology Data Exchange (ETDEWEB)
Solar heating of gas turbine plants steps back more and more into the focus of current research. The mainly instationary operation of solar turbine power plants can only be predicted with sufficient accuracy if the transient behaviour of the receiver for the solar radiation is known. Therefore the transient behaviour of cavity receivers of different design is investigated. The mathematical model used for the simulation of the heat transfer and energy storage processes is illustrated. Computed results for receivers with various inner lining are compared and evaluated concerning their use in practice.
1987-03-01
Transient behavior of solar heated radiation receivers for small gas turbine power plants
Energy Technology Data Exchange (ETDEWEB)
Solar heating of gas turbine plants is moving back to the focus of current research. The mainly unsteady operation of solar turbine power plants can only be predicted with sufficient accuracy if the transient behavior of the solar radiation receiver is known. Therefore the transient behavior of cavity receivers of different designs is investigated. The mathematical model used to simulate heat transfer and energy storage is illustrated. Computed results for two receivers with different inner lining are compared and evaluated concerning their use in practice.
1987-01-01
Energy Technology Data Exchange (ETDEWEB)
In this note it is suggested that binuclear platinum(II) complexes with a solely inorganic bridging pyrophosphito ligand also possess many of the complementary advantages of inorganic and organic dyes. They are evaluated for their potential use as a luminescent solar concentrator material. The disadvantages include: the high cost of platinum; the absorption spectra in solution shows a weaker absorption at 452 nm which may cause reabsorption of emitted light; the positions of the absorption and emission maxima are not at the optimal wavelengths for absorption of sunlight and emission to a solar cell. In spite of these drawbacks the author believes the platinum complexes merit consideration for fabrication of solar concentrator devices.
1986-01-01
Solar energy receiver for a Stirling engine
Energy Technology Data Exchange (ETDEWEB)
A solar energy receiver is described including a separable endless wall formed of a ceramic material having defined therein a cavity of a substantially cylindrical configuration for entrapping solar flux, and an acceptance aperture adapted to admit to the cavity a concentrated beam of solar energy, said wall being characterized by at least a pair of contiguously related segments separated by lines of cleavage intercepting said aperture, at least one of the segments being supported for pivotal displacement, and a thermal responsive actuator adapted to respond to excessive temperatures within the cavity for initiating pivotal displacement of said one segment, whereby thermal flux is permitted to escape from the cavity.
1980-12-02
Plastics with a bright future; Kunststoffe mit leuchtender Zukunft
Energy Technology Data Exchange (ETDEWEB)
Flexible solar cells or luminous foils have become reality with organic electronic systems.
2010-07-01
British Library Electronic Table of Contents (United Kingdom)
The Monte Carlo ray-tracing method is applied and coupled with optical properties to predict the radiation performance of solar concentrator/cavity receiver systems. Several different cavity geometries are compared on the radiation performance. A flux density distribution measurement system for dish parabolic concentrators is developed. The contours of the flux distribution for target placements at different distances from the dish vertex of a solar concentrator are taken by using an indirect method with a Lambert and a charge coupled device (CCD) camera. Further, the measured flux distributions are compared with a Monte Carlo-predicted distribution. The results can be a valuable reference for the design and assemblage of the solar collector system.
2010-01-01
MILSTAR's flexible substrate solar array: Lessons learned, addendum
MILSTAR's Flexible Substrate Solar Array (FSSA) is an evolutionary development of the lightweight, flexible substrate design pioneered at Lockheed during the seventies. Many of the features of the design are related to the Solar Array Flight Experiment (SAFE), flown on STS-41D in 1984. FSSA development has created a substantial technology base for future flexible substrate solar arrays such as the array for the Space Station Freedom. Lessons learned during the development of the FSSA can and should be applied to the Freedom array and other future flexible substrate designs.
1990-01-01
International Science & Technology Center (ISTC)
The Development of Basic Plasma-Chemical Technology for Manufacture of Low Cost Crystal Silicon for Solar Power Plants.
Laser-assisted solar cell metallization processing. Quarterly report, December 1984-February 1985
Energy Technology Data Exchange (ETDEWEB)
Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are investigated, developed, and characterized. The tasks comprising these investigations are outlined. A new batch of solar cells was processed using the laser decomposition of spun-on silver neodecanoate to metallize cells. Decomposition of silver neodecanoate was carried out at different laser powers on different cells on a given wafer to determine whether this would have any effect on cell performance. Solar cells which were written with laser powers of 5 to 8 watts, gave excellent results with cell efficiencies in the range of 14 to 16%.
1985-04-04
Energy Technology Data Exchange (ETDEWEB)
The performance of a solar chemical heat pipe was studied using CO{sub 2}reforming of methane as the endothermic reaction. A directly heated vertical reactor, packed with a rhodium catalyst was used. The solar tests were carried out in the Schaeffer solar furnace of the Weizmann Institute of Science. The power absorbed was up to 6.3 KW, the maximal flow rates of the gases reached 11,000 1/h, and the methane conversions reached 85%. A computer model was developed to simulate the process. Agreement of the calculations with the experimental results was quite satisfactory.
1992-01-01
Energy Technology Data Exchange (ETDEWEB)
This proceedings volume contains contributions by about 70 authors on market trends, funding, marketing, boundary conditions and sales promotion of thermal solar energy and photovoltaic systems. The contributions reflect the diversity of authors, e.g. consultants, advocates and agents of solar technology producers and financial organisations. Central issues were markets in and outside Europe, quality assurance, interdepartmental cooperations, and marketing strategies of the solar industry. The proceedings volume also contains the conference schedule and self-descriptions of the authors' institutions. (orig.)
2002-07-01
International Nuclear Information System (INIS)
The investigation of important wear processes in the railway technique, especially the differentiation of the parameters influencing the wear process, requires extensive test programmes and thus high resolving methods to determine the wear. Radiometric methods enable considerably greater measuring accuracy with the help of the activation of materials than an observation of measurement or measuring changes. (orig./LH).
1975-04-03
Washboard modes as ELM-related events in JET
Energy Technology Data Exchange (ETDEWEB)
Washboard (WB) modes (Smeulders P et al 1999 Plasma Phys. Control. Fusion 41 1303) are a very common edge instability regularly observed in the H-mode regime in JET. They are detected as (normally several) bands of continuously fluctuating magnetic activity rotating in the direction of the electron diamagnetic drift with typical frequencies in the range of 10-90 kHz. The time evolution of the WB mode frequency is found to follow qualitatively the evolution of the electron temperature measured near the pedestal top, probably due to the strong diamagnetic drift associated with the large pedestal gradients. Evidence for their involvement in the pedestal and ELM dynamics will be presented. Increasing WB mode amplitude is correlated with an increase in the time between consecutive type-I ELMs. In situations in which a sudden increase (decrease) of WB mode activity is observed, the build-up of the pedestal ...
2004-01-01
Transient enhanced diffusion and deactivation of ion-implanted As in strained Si
International Nuclear Information System (INIS)
First results on the effects of strain on transient enhanced diffusion and deactivation of As-implanted ultrashallow junctions are presented. A significant effect of strain on the magnitude and timescale of transient enhanced diffusion is observed, which is consistent with the stabilization of interstitial-type defects by tensile strain. Our results show no significant impact of strain on As electrical activity during the deactivation timescale accessed in this study.
2005-08-01
Radiation-annealing hardening of vanadium
International Nuclear Information System (INIS)
A study is made of the mechanical properties of vanadium irradiated with fast neutrons up to dose 8.6.10"-"4 dpa, as a function of the temperature of post-radiation annealing. The radiation-annealing hardening (RAH) effect is observed at 300"oC, in agreement with previous studies. It is established for the first time that RAH is accompanied by fall in ductility. A phenomenological model is described which explains the dependence of RAH on radiation dose and temperature, as well as on the content of chemically active alloying impurities. (author).
Radiation-annealing hardening of vanadium
International Nuclear Information System (INIS)
Mechanical properties of vanadium, irradiated with fast neutrons up to 8.6x10"-"4 dpa depending on postirradiation annealing temperature, are studied. It is shown that radiation-annealing hardening (RAH) is observed at 300 deg C, which agrees with earlier performed studies. It is first stated that RAH is accompanied by plasticity decrease. Phenomenological model permitting to explain RAH dependence on irradiation temperature and dose and also on content of chemically active alloying impurities is suggested.
Primary structure of streptococcal Pep M5 protein: Absence of extensive sequence repeats
UK PubMed Central (United Kingdom)
Extensive sequence repeats have been observed in a biologically active fragment of type 24 streptococcal M protein, namely Pep M24 [Beachey, E. H., Sayer, J. M. & Kang, A. H. (1978) Proc....Full Text Available
1983-09-01
Mobilization of plutonium burdens during pregnancy
International Nuclear Information System (INIS)
The mobilization and distribution of previously deposited "2"3"9Pu was compared in pregnant rats (15 and 20 days of gestation) and nonpregnant controls. Pregnancy had little effect on "2"3"9Pu tissue burdens and only minimal activity appeared in the fetoplacental unit. Marked differences were observed in tracer "4"5Ca deposition patterns between the experimental groups.
1977-05-01
Lipase catalyzed esterification in AOT reverse micelles: a structural study.
AOT reverse micelles are used to cosolubilize hydrophilic and hydrophobic reactants of lipase catalysed esterification. Depending on the nature of the alcohol, a drastic change of the initial rate of the esterification is observed. A structural study of the micellar system with and without reactant is undertaken to explain the change in the activity with the various alcohols. PMID:7832997
1995-01-01
Fluctuations of the energy of Stokes pulses of resonance coherent SRS
International Nuclear Information System (INIS)
An analytic solution is obtained for the equations of resonance coherent SRS by neglecting the population of the final level of the Raman transition for the systems with the active-medium length that is smaller than the wavelength of the incident light. For the extended systems, a numerical solution is obtained. The energy distribution of the Stokes pulses is found. The large-scale (about 100%) fluctuations of the Stokes radiation energy were observed in the case of unsaturated amplified spontaneous emission. (nonlinear optical phenomena)
2000-11-30
The renaissance of solar homes; Le renouveau des maisons solaires
Energy Technology Data Exchange (ETDEWEB)
This publication of the Areva Group, a world nuclear industry leader, provides information on the energy in many domains. This issue deals with the nuclear fuel cycle, the biofuels, the everyday geothermal power, the Unites States energy supply and types, the Bertrand Picard solar aircraft, the kyoto protocol and the wind power leaders. A special chapter is devoted to the renaissance of solar homes. (A.L.B.)
2004-07-01
Solar-powered humidification dehumidification desalination system
Energy Technology Data Exchange (ETDEWEB)
Presented are some preliminary studies made in preparation for the design of a solar powered loop for desalination by humidification - dehumidification process. The studies concentrated on the evaluation of different parameters affecting the performance of the combination of different components in such a loop in the hope of outlining the most decisive factors for the choice or design of solar collectors or heat source. The results presented relate to the performance of two of the most important components in a loop of such purpose, that is: the humidifying and the dehumidifying columns or stacks. 4 refs.
1980-01-01
Solar aeroplane. Solair I: the answer for alternative flying
Energy Technology Data Exchange (ETDEWEB)
In December 1980, Guenther Rochelt from Munich (FRG) managed the first flight in a solar aircraft. Energy was supplied by 2,500 solar cells with a rated power of 2.2 kW. Self-starting and flying were made possible by a special aircraft construction with an electromotor with a gross power of 1.8 and a rated voltage of 88 V.
1981-03-01
Energy Technology Data Exchange (ETDEWEB)
Literature summarizing a study on the Saudi Arabian solar controlled environment agriculture system is presented. Specifications and performance requirements for the system components are revealed. Detailed performance and cost analyses are used to determine the optimum design. A preliminary design of an engineering field test is included. Some weather data are provided for Riyadh, Saudi Arabia. (BCS)
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
This volume on specifications for the Saguaro Power Plant includes the following: subsystem interface definition document; solar collector subsystem specification; receiver specification; thermal energy storage specification; solar steam generator specification; and master control system specification.
1983-09-01
Performance testing of the FMC Fresnel-Belt Concentrating Solar Collector
Energy Technology Data Exchange (ETDEWEB)
The results of tests performed on the FMC Fresnel-Belt Solar Collector at the Midtemperature Solar Systems Test Facility are summarized. Tests were conducted over a temperature range from 100 to 250/sup 0/C. Test objectives are defined, test procedures are described, and test results and conclusions are given.
1980-01-01
Performance estimates for attached-sunspace passive solar heated buildings
Energy Technology Data Exchange (ETDEWEB)
Performance predictions have been made for attached-sunspace types of passively solar heated buildings. The predictions are based on hour-by-hour computer simulations using computer models developed in the framework of PASOLE, the Los Alamos Scientific Laboratory (LASL) passive solar energy simulation program. The models have been validated by detailed comparison with actual hourly temperature measurements taken in attached-sunspace test rooms at LASL.
1980-01-01
Impact of lateral junction on selective emitter solar cell performance
Energy Technology Data Exchange (ETDEWEB)
Investigation of selective emitter solar cells has been undertaken using both device fabrication and accurate two-dimensional simulation program. Our results show that selective emitter solar cells exhibit a relatively low fill factor because of minority carriers crowding at the lateral junction. It is also found that carrier recombination in the space-charge region of the lateral junction limits open-circuit voltage improvements
1998-09-14
Heat exchange in a multi-cavity volumetric solar receiver
Energy Technology Data Exchange (ETDEWEB)
The concept of a multi-cavity volumetric solar receiver is very attractive for the profitability of certain of its characteristics such as high efficiency and economy. The absorber is based on a pack of small ceramic cavities which intercept and absorb the inherent high solar flux reflected from an array of mirrors. Atmospheric air acts as a coolant medium when it is drawn through the pack. A model for an overall heat transfer performance of the receiver is given and numerically solved.
1991-01-01
Final report - Sundyne Company
Energy Technology Data Exchange (ETDEWEB)
Solar cookers offer a viable alternative to conventional cooking methods in many areas, and can be an effective tool in the fight against the deforestation and desertification that plague many developing countries. However, there have been numerous obstacles to the successful dissemination of solar cookers in the past. The purpose of this paper is to identify opportunities, review constraints and develop a marketing strategy to disseminate the Sundyne Solar Cooker (SSC) in developing countries.
1994-09-27
Evaluation of alternative battery technologies for a solar assist plug-in hybrid electric tractor
British Library Electronic Table of Contents (United Kingdom)
This paper looks at the various battery technologies available for use in solar assist plug-in hybrid electric tractors In this context, solar assist plug-in hybrid electric tractors are those that may be used in light-duty agricultural operations. To determine the most suitable battery, four common technologies are analyzed looking at the environmental life-cycle effects and costs.
2010-01-01
Environmental data for sites in the national solar data network
Energy Technology Data Exchange (ETDEWEB)
The Department of Energy's National Solar Data Program established solar energy systems in residential and commercial buildings across the United States. These solar sites are linked to Vitro Laboratories Division's computer in the National Solar Data Network (NSDN). Vitro collects and analyzes data from this network to determine the thermal performance of each of the solar systems. The network consists of: (1) sensors which measure key performance parameters at a selected site; (2) a Site Data Acquisition Subsystem (SDAS); (3) telephone transmission circuits; and (4) a Central Data Processing System (CDPS). For the majority of parameters, raw data is collected approximately every five minutes. Solar insolation and certain other parameters, which are subject to rapid variance, are sampled every 32 seconds. Environmental information collected at ...
1980-07-01
Dynamic behavior of a solar-heated receiver of a gas turbine plant
Energy Technology Data Exchange (ETDEWEB)
The mainly nonstationary operation of a solar-heated receiver can be simulated with sufficient accuracy only if data about the dynamic behavior are available. For this reason, the dynamic behavior of a solar cavity receiver with parabolic dish collector is investigated. The development of a mathematical simulation considering heat transfer and storage processes is presented and the procedure for a numerical solution is illustrated. The performance of the calculation method is finally demonstrated by simulating the passage of a cloud.
1987-01-01
Dynamic behavior of a solar heated receiver of a gas turbine plant
Energy Technology Data Exchange (ETDEWEB)
The mainly instationary operation of a solar heated receiver can be simulated with sufficient accuracy only if data about the dynamic behavior are available. For this reason, the dynamic behavior of a solar cavity receiver with parabolic dish collector is investigated. The development of a mathematical simulation considering heat transfer and storage processes is presented and the procedure for a numerical solution is illustrated. The performance of the calculation method is finally demonstrated by simulating the passage of a cloud.
1986-01-01
Energy Technology Data Exchange (ETDEWEB)
Installation of the electrical equipment at the Barstow Solar Pilot Plant is the concern of this construction package. Technical specifications for power and instrument cables, meteorological instruments, and control cables are defined. The documentation requirements are briefly discussed.
1980-07-01
Energy Technology Data Exchange (ETDEWEB)
A strong dependence of thermal activation energy (TAE) on infrared (IR) stimulation time for the infrared stimulated luminescence (IRSL) signal was observed for K-feldspar grains extracted from several sediments and granites from China. A TAE value as low as {approx}0.1 eV was observed at the beginning of IR stimulation and increased to {approx}0.45 eV after 90 s. For a trap depth of {approx}2 eV below the conduction band for the IRSL traps, the TAE value of {approx}0.45 eV is consistent with the energy gap between the excited states ({approx}0.5 eV below the conduction band) and conduction band. This phenomenon is explained as the result of the coexistence of thermally assisted recombination via conduction band or band-tail states hopping and athermal tunnelling recombination of electrons from the excited states under IR stimulation, leading to the observation of a higher anomalous fading rate in the ...
2010-08-15
Some highlights of phase-C commissioning of Tarapur-4 the first to be synchronized 540 MWe PHWR
International Nuclear Information System (INIS)
Commissioning of a Pressurized heavy water reactor (PHWR) plant of NPCIL involves three phases viz phase-A which consist of pre-criticality activities such as hydro test, air hold test, no load test of motors etc., phase-B consist of criticality and post criticality physics experiments. The phase-C, which is considered the major phase, consist of initial power raise to about 10 % , TG rolling, synchronization, going to significant power in steps and performance tests such as load rejection tests from various power levels. In order to have smooth commissioning for the Phase-C, an integrated team consisting of engineers from various design and analysis groups of NPCIL headquarters was formed to participate along with site O and M engineers, closely observe and coordinate phase-C commissioning activities. During this commissioning some major events and observations took place. An attempt is made to bring ...
2006-11-13
DEFF Research Database (Denmark)
Connective tissue in biopsy specimens taken from the lower part of the uterine cervix in 40 pregnant women at various gestational ages was compared to that in similar biopsy specimens from 15 nonpregnant women. The concentrations of collagen, sulfated glycosaminoglycans, and hyaluronic acid decreased during pregnancy. At the gestational age of 10 weeks, the collagen concentration was 70%, and at term 30%, of that in the nonpregnant cervix. After delivery, no further decrease was observed. The extractability of collagen increased during pregnancy, as well as during labor. Also, the water concentration increased. An increase in the collagenolytic activity was observed with advancing gestational age. The 2,4-dinitrophenyl-Pro-Gln-Gly-Ile-Ala-Gly-Gin-D-Arg hydrolytic activity (collagenase) and the concentration of leukocyte elastase increased gradually by a factor of 10. The physiologic importance of the ...
1983-01-01
International Nuclear Information System (INIS)
Chorismate mutase, a branch-point enzyme in the aromatic amino acid pathway of Saccharomyces cerevisiae, and also a mutant chorismate mutase with a single amino acid substitution in the C-terminal part of the protein have been purified approximately 20-fold and 64-fold from overproducing strains, respectively. The wild-type enzyme is activated by tryptophan and subject to feedback inhibition by tyrosine, whereas the mutant enzyme does not respond to activation by tryptophan nor inhibition by tyrosine. Both enzymes are dimers consisting of two identical subunits of M_r 30,000, each one capable of binding one substrate and one activator molecule. Each subunit of the wild-type enzyme also binds one inhibitor molecule, whereas the mutant enzyme lost this ability. The enzyme reaction was observed by "1H NMR and shows a direct and irreversible conversion of chorismate to prephenate without the accumulation of ...
Thermal performance simulation of a solar cavity receiver under windy conditions
British Library Electronic Table of Contents (United Kingdom)
Solar cavity receiver plays a dominant role in the light-heat conversion. Its performance can directly affect the efficiency of the whole power generation system. A combined calculation method for evaluating the thermal performance of the solar cavity receiver is raised in this paper. This method couples the Monte-Carlo method, the correlations of the flow boiling heat transfer, and the calculation of air flow field. And this method can ultimately figure out the surface heat flux inside the cavity, the wall temperature of the boiling tubes, and the heat loss of the solar receiver with an iterative solution. With this method, the thermal performance of a solar cavity receiver, a saturated steam receiver, is simulated under different wind environments. The highest wall temperature of the boi...
2011-01-01
Thermal gradient humidification-dehumidification desalination system
Energy Technology Data Exchange (ETDEWEB)
A solar energy desalination process utilizing solar radiation directly for the evaporation of salt water is described. Ambient air takes on water vapor as the air passes through an evaporative medium. It is then directed between a saline water-covered, solar absorbing surface and a solar collecting housing. The resulting heated and moisture-saturated air is cooled in a heat exchange means where condensation of fresh water occurs. Simultaneously, cool salt water is utilized as the cooling water in the heat exchange means, and takes on the heat of condensation given up by the condensing vapor. The heated salt water from the heat exchange means is partially directed over the solar absorbing surface, and at least a portion of it is also directed to wet the evaporative medium. Several optional sub-processes are described for operation of the system during periods of reduced insolation, ...
1982-12-14
British Library Electronic Table of Contents (United Kingdom)
In the last years, the growing demand for air conditioning has caused a significant increase in demand for primary energy resources. Solar-powered cooling is one of the technologies which allows to obtain, by using the renewable solar source, an important energy saving compared to traditional air conditioning plants. The paper describes different technical installations for solar cooling, their way of operation, advantages and limits. The objective of the present study has been to analyze the technical and economic feasibility of solar absorption cooling systems, designed for two different application fields: industrial refrigeration and air conditioning. The possibility to replace or integrate the existing plants is studied, by considering the refrigeration requirements of a company, whic...
2009-01-01
Solar energy apparatus with apertured shield
Energy Technology Data Exchange (ETDEWEB)
This paper describes in an apparatus for absorbing a beam of concentrated solar energy and which includes a cavity receiver with an inlet for transmission thereinto of solar radiation, a protective apertured shield means about the inlet. It comprises: rigid support means fixed to the periphery of the inlet and projecting radially inwardly therefrom to define a generally central aperture area through which the solar radiation can pass into the cavity receiver; and non-structural blanket means spread over the rigid support means between the periphery of the inlet and the aperture area, the material having a high temperature capability and providing for infra-red radiation insulation, while remaining relatively cool when subjected to solar radiation.
1989-07-25
Radiative properties of a solar cavity receiver/reactor with quartz window
British Library Electronic Table of Contents (United Kingdom)
An energy transfer and conversion model for high-temperature solar cavity receivers has been developed using the transport behaviour of solar radiation as described by the spectral radiative exchange factors. A Monte-Carlo ray-tracing method coupled with optical properties was adopted, to predict radiation characteristics of the solar collector system by calculating radiative exchange factors. A cavity receiver with a plano-convexo quartz window was proposed, based upon the directional characteristics of the focal flux and the redistribution effect of the quartz window. Parametric studies on the windowed receiver provided a more uniform flux distribution, higher efficiency and lower loss than the windowless receivers. The predicted results serve as a design reference for the solar receiver...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
This is a process for manufacturing a semi-rigid, folding solar generator manufactured from several coated solar cells (Cics), which has at least two folding parts connected together so as to turn by hinges, characterized by the following stages of the process: a) On the back of matrix subsections, in order to cover the connector, carbon fibre strips are glued on, which project over the upper or lower edge of each matrix subsection. b) The projecting ends of adjacent carbon fiber strips are connected with two carbon fibre strips. c) At least two matrix subsections are fixed in separately manufactured carbon fiber frames, and d) the carbon fiber frames, together with the matrix subsections are connected via hinges to a solar generator.
1985-10-31
Passive solar design handbooks: Vol III: passive solar design analysis and supplement
Energy Technology Data Exchange (ETDEWEB)
This book applies the Los Alamos Solar Load Ratio (SLR) method to the design of passive solar heating systems, with an emphasis on the average annual heating energy consumption. Recommendations are given on minimizing heating energy consumption by appropriate choices of conservation level and solar system parameters. Analytical methods and supporting tables are presented which enable simple, fast estimates of the heating energy consumption as part of the design process. Topics considered include SLR correlations, the load collector ratio (LCR) method, sensitivity data, cooling considerations, conservation formulas, design procedure, life-cycle costs, high-mass direct gain buildings, low-mass sun-tempered buildings, sunspaces, off-reference night insulation, correlation equations, and mixed systems.
1983-01-01
Glass-heat-pipe evacuated-tube solar collector
A glass heat pipe is adapted for use as a solar energy absorber in an evacuated tube solar collector and for transferring the absorbed solar energy to a working fluid medium or heat sink for storage or practical use. A capillary wick is formed of granular glass particles fused together by heat on the inside surface of the heat pipe with a water glass binder solution to enhance capillary drive distribution of the thermal transfer fluid in the heat pipe throughout the entire inside surface of the evaporator portion of the heat pipe. Selective coatings are used on the heat pipe surface to maximize solar absorption and minimize energy radiation, and the glass wick can alternatively be fabricated with granular particles of black glass or obsidian.
1981-08-06
Experimental Investigation of Solar Drying for Orange Peels by Forced convection
International Nuclear Information System (INIS)
Solar drier does not degrade any more the dried products with the manner of the products dried at the natural sun. The drying unit is composed mainly of a solar air collector and an enclosure of drying. The transformation of the solar radiation into heat is done thanks to the solar collector whose effectiveness is increased by the addition of suitable baffles in the mobile air vein. The efficiency of the collector reaches then 80. The hot air on the outlet side of the collector arrives in the enclosure of drying where the heat transfer with the product to be dried is done by convection. The kinetics drying study shows that in addition to the dependence of the temperature and air velocity of drying, the speed of drying also depends on fragmentation on the product to dry, and mainly, of the product surface in contact with the drying air. Thus, the hygrometry is reduced from 76 to 13 pour cent in one day.. ...
2009-01-30
Exergy analysis of the solar multi-effect humidification?dehumidification desalination process
British Library Electronic Table of Contents (United Kingdom)
An exergy analysis method is presented of the solar multi-effect humidification?dehumidification desalination (HDD) process. Pinch technology is used in the humidification process to determine the maximum possible saturated air temperature and the temperature of water rejected from the unit, and then the dehumidification process to determine the temperature of water leaving from the heat exchanger. The formulae to calculate the exergy of water and saturated air are given. The solar plane collector is used. From exergy analysis, the solar collector has the lowest exergy efficiency; the HDD process has a lower exergy efficiency, and the water rejected has also a large exergy loss. The energy and exergy recovery rate of the desalination process is also lower. The solar multi-effect HDD proces...
2007-01-01
Design of a GaAs/Ge solar array for unmanned aerial vehicles
Energy Technology Data Exchange (ETDEWEB)
Unmanned Aerial Vehicles (UAV) are being proposed for many applications including surveillance, mapping and atmospheric studies. These applications require a lightweight, low speed, medium to long duration airplane. Due to the weight, speed, and altitude constraints imposed on such aircraft, solar array generated electric power is a viable alternative to air-breathing engines. Development of such aircraft is currently being funded under the Environmental Research Aircraft and Sensor Technology (ERAST) program. NASA Lewis Research Center (LeRC) is currently building a Solar Electric Airplane to demonstrate UAV technology. This aircraft utilizes high efficiency Applied Solar Energy Corporation (ASEC) GaAs/Ge space solar cells. The cells have been provided by the Air Force through the ManTech Office. Expected completion of the plane is early 1995, with the airplane currently undergoing flight testing using ...
1995-03-01
Comparison of a cavity solar receiver numerical model and experimental data
Energy Technology Data Exchange (ETDEWEB)
Results from a numerical model of axisymmetric solar cavity receivers are compared with experimental data for tests of a novel test bed receiver in the Saudi National Laboratories solar furnace. The computed energy transfer rates and temperatures are compared with the experimental data for different receiver geometries, aperture sizes, and operating conditions. In general, the agreement between the numerical model and the experimental data is better for the small-to-midsized apertures than for the large apertures. The analysis indicates that for the larger apertures, the convective heat losses are overpredicted. It also suggests that these losses could be better characterized. Sensitivity analyses show that both the total solar energy input rate and the convective heat-loss coefficient significantly affect the receiver thermal performance and that the distribution of the input solar flux significantly ...
1990-08-01
Aerodynamic and structural design of a solar-powered micro unmanned air vehicle
Energy Technology Data Exchange (ETDEWEB)
The field of micro unmanned aerial vehicles ({mu}UAVs) has advanced rapidly in recent years. This paper studies the design and construction of a small solar-powered aircraft near the size range of current {theta}UAVs. A number of aspects of their design were analysed, including structural, aerodynamic and propulsion system considerations. The effect of small-scale, low Reynolds number aerodynamics was investigated, and the performance of a range of candidate aerofoils was compared. The integration of a solar power source into the aircraft system was considered a key design issue. Consequently, a number of aircraft configurations were examined, with the intention of optimising the application of solar power in a miniature aircraft. Investigation of improved system components suggests that a practical solar-powered aircraft in the size range below 500 mm maximum linear dimension should be viable given ...
2000-04-01
A study of solar-powered, high-altitude unmanned aerial vehicles
British Library Electronic Table of Contents (United Kingdom)
Purpose ? Aims to present a methodology for analysing a solar-electric, high-altitude, long-endurance, unmanned aircraft. Design/methodology/approach ? The study focuses on the aerodynamics, flight performance and power requirements of a heavier-than-air, solar-electric, HALE UAV. The methodology is founded on using an analytical approach to determine the power required to undertake various flight manoeuvres. An analytical approach is also undertaken in determining the intensity of the solar radiation available to the aircraft. Finally to demonstrate the methodology, a HALE concept was generated and evaluated. Findings ? When using estimates of current solar-electric propulsion and energy conversion efficiencies, the HALE concept was only able to sustain year round, level flight up to lati...
2006-01-01
British Library Electronic Table of Contents (United Kingdom)
This paper presents a hybrid solar desalination process of the multi-effect humidification dehumidification and the basin-type unit. The sketch of the hybrid solar desalination process is given. The solar vacuated tube collector is employed in the desalination system, multi-effect humidification dehumidification desalination (HDD) process is plotted according to pinch technology, and then the water rejected from multi-effect HDD process is reused to desalinate in a basin-type unit further. The gain output ratio (GOR) of this system will rise by 2?3 at least through reusing the rejected water. The research proves that the multi-effect HDD has much room to be improved. A hybrid solar desalination process of the multi-effect humidification dehumidification and the basin-type unit should be no...
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
The paper reported the results of fiscal 1994 studies on solar energy in the New Sunshine Project. Relating to the technical development for the practical use of photovoltaic power systems, the development of manufacturing technologies for low-cost substrates and the development of element technology for manufacturing low-cost polycrystalline cells/modules were reported as the development of technology for thin substrate polycrystalline solar cells for practical use. As to the research on fabrication technology for thin film solar cells for practical use, reports were made on the research on low-cost fabrication technology for large-area modules and the technological development for qualitative improvement, etc. In respect to the technological development for super-high efficiency solar cells, reported were the technological development for super-high efficiency single crystalline silicon ...
1994-12-01
Energy Technology Data Exchange (ETDEWEB)
At COP3 in 1997, an agreement was made to the innovative technical development/promotion by international cooperation, and the promotion of transfer of environmental technology to developing countries. Under the agreement, a feasibility study of international cooperation was made, and especially a study was conducted of the utilization/development of solar energy by the innovative solar thermochemical process. The main reason for global warming is emissions of a large amount of CO2 caused by the direct combustion of fossil fuels. Therefore, a CO2 recycle system taken up in the study enables a more substantial decline in CO2 emission (kg/kWh) per unit generation than the conventional thermal power system by composing solar methanol or solar dimethyl ether using fossil fuels including coal, water, CO2, etc. as raw materials and using solar energy as heat source, and by using this as ...
1998-03-01
IL-4/Stat6 activities correlate with apoptosis and metastasis in colon cancer cells
International Nuclear Information System (INIS)
IL-4-induced Stat6 signaling is active in a variety of cell types and plays a role in cell proliferation/growth and resistance to apoptosis. Using EMSA, we identified differential IL-4/Stat6 activities in colorectal cancer cell lines, HT-29 being active Stat6"h"i"g"h phenotype and Caco-2 being defective Stat6"n"u"l"l phenotype, respectively. Active Stat6"h"i"g"h HT-29 cells exhibited resistance to apoptosis by flowcytometry and aggressive metastasis by Transwell assay compared with defective Stat6"n"u"l"l Caco-2 cells. Comparing one another using RT-PCR, Stat6"h"i"g"h HT-29 cells expressed more mRNA of anti-apoptotic and pro-metastatic genes Survivin, MDM2, and TMPRSS4, while Stat6"n"u"l"l Caco-2 cells expressed more mRNA of pro-apoptotic and anti-metastatic genes BAX, CAV1, and P53, respectively. This is the first study describing correlations of IL-4/Stat6 activities with ...
2008-05-02
Turning the Moon into a Solar Photovoltaic Paradise
Lunar resource utilization has focused principally on the extraction of oxygen from the lunar regolith. A number of schemes have been proposed for oxygen extraction from Ilmenite and Anorthite. Serendipitously, these schemes have as their by-products (or more directly as their "waste products"), materials needed for the fabrication of thin film silicon solar cells. Thus lunar surface possesses both the elemental components needed for the fabrication of silicon solar cells and a vacuum environment that allows for vacuum deposition of thin film solar cells directly on the surface of the Moon without the need for vacuum chambers. In support of the US space exploration initiative a new architecture for the production of thin film solar cells on directly on the lunar surface is proposed. The paper discusses experimental data on the fabrication and properties of lunar glass substrates, evaporated lunar ...
2006-01-01
The Role of Massive Agb Stars in the Early Solar System Composition
We demonstrate that a massive asymptotic giant branch (AGB) star is a good candidate as the main source of short-lived radionuclides in the early solar system. Recent identification of massive (4-8 solar masses) AGB stars in the Galaxy, which are both lithium- and rubidium-rich, demonstrates that these stars experience proton captures at the base of the convective envelope (hot bottom burning), together with high-neutron density nucleosynthesis with 22Ne as a neutron source in the He shell and efficient dredge-up of the processed material. A model of a 6.5 solar masses star of solar metallicity can simultaneously match the abundances of 26Al, 41Ca, 60Fe, and 107Pd inferred to have been present in the solar nebula by using a dilution factor of 1 part of AGB material per 300 parts of original solar nebula material, and taking into account a time interval between ...
2008-01-01
Energy Technology Data Exchange (ETDEWEB)
An experimental investigation of a humidification-dehumidification desalination (HDD) process using solar energy at the weather conditions of Suez City, Egypt, is presented. A test rig is designed and constructed to conduct this investigation under different environmental and operating conditions. The test rig consists of a solar water heater (concentrator solar collector type), solar air heater (flat plate solar collector type), humidifier tower and dehumidifier exchanger. Different variables are examined including the feed water flow rate, the air flow rate, the cooling water flow rate in the dehumidifier and the weather conditions. Comparisons between the experimental results and other published results are presented. It is found that the results of the developed mathematical model by the same authors are in good agreement with the experimental results. The tested results show ...
2004-05-01
International Nuclear Information System (INIS)
An experimental investigation of a humidification-dehumidification desalination (HDD) process using solar energy at the weather conditions of Suez City, Egypt, is presented. A test rig is designed and constructed to conduct this investigation under different environmental and operating conditions. The test rig consists of a solar water heater (concentrator solar collector type), solar air heater (flat plate solar collector type), humidifier tower and dehumidifier exchanger. Different variables are examined including the feed water flow rate, the air flow rate, the cooling water flow rate in the dehumidifier and the weather conditions. Comparisons between the experimental results and other published results are presented. It is found that the results of the developed mathematical model by the same authors are in good agreement with the experimental results. The tested results show ...
2004-05-01
Energy Technology Data Exchange (ETDEWEB)
An experimental investigation of a humidification-dehumidification desalination (HDD) process using solar energy at the weather conditions of Suez City, Egypt, is presented. A test rig is designed and constructed to conduct this investigation under different environmental and operating conditions. The test rig consists of a solar water heater (concentrator solar collector type), solar air heater (flat plate solar collector type), humidifier tower and dehumidifier exchanger. Different variables are examined including the feed water flow rate, the air flow rate, the cooling water flow rate in the dehumidifier and the weather conditions. Comparisons between the experimental results and other published results are presented. It is found that the results of the developed mathematical model by the same authors are in good agreement with the experimental results. The tested results show ...
2004-05-01
Solar desalination using humidification dehumidification processes. Pt. 1. A numerical investigation
Energy Technology Data Exchange (ETDEWEB)
A numerical investigation of a humidification dehumidification desalination (HDD) process using solar energy is presented. The HDD system consists mainly of a concentrating solar water heating collector, flat plate solar air heating collector, humidifying tower and dehumidifying exchanger. Two separate circulating loops constitute the HDD system, the first for heating the feed water and the second for heating air. A mathematical model is developed, simulating the HDD system, to study the influence of the different system configurations, weather and operating conditions on the system productivity. The model validity is examined by comparing the theoretical and experimental results of the same authors. It is found that the results of the developed mathematical model are in good agreement with the experimental results and other published works. The results show also that the productivity of the unit is strongly influenced by ...
2004-05-01
Energy Technology Data Exchange (ETDEWEB)
A numerical investigation of a humidification dehumidification desalination (HDD) process using solar energy is presented. The HDD system consists mainly of a concentrating solar water heating collector, flat plate solar air heating collector, humidifying tower and dehumidifying exchanger. Two separate circulating loops constitute the HDD system, the first for heating the feed water and the second for heating air. A mathematical model is developed, simulating the HDD system, to study the influence of the different system configurations, weather and operating conditions on the system productivity. The model validity is examined by comparing the theoretical and experimental results of the same authors. It is found that the results of the developed mathematical model are in good agreement with the experimental results and other published works. The results show also that the productivity of the unit is strongly influenced by ...
2004-05-01
High-efficiency GaAs solar cells
Energy Technology Data Exchange (ETDEWEB)
An updated review of the state of the art in the development of GaAs solar cells is provided, with emphasis on AlGaAs-GaAs cells suitable for space applications. A set of theoretically derived characteristics is given for this type of solar cell. Comparison of measured performance with theory shows excellent agreement. Data on the effects of radiation damage (high-energy electrons, protons, and neutrons) is also integrated into a form useful for evaluation purposes. Techniques for fabricating (AlGa)As-GaAs solar cells in quantities large enough for practical applications are discussed and are shown to have been demonstrated. The possibility of extending these techniques to the fabrication of very thin low-weight cells for space applications is also considered. Finally, the results obtained to date in the development of GaAs solar cells for applications requiring concentrated sunlight are reviewed, for ...
1984-05-01
Fly on the wings of the sun - a study of solar-powered aircraft
Energy Technology Data Exchange (ETDEWEB)
Solar High Altitude Powered Platform (Solar HAPP) aircraft are unmanned remote sensing vehicles designed for cruises lasting up to one year at 20-km altitude, while carrying up to 250 pounds of cameras and electrooptic sensors in an underslung payload pod. It is anticipated that real time IR and UV images of earth features may be more inexpensively and accurately obtained by this means than by the conventional geosynchronous earth resources satellites. Solar HAPPs, with wing spans of over 300 ft and weights of only 2000 lb, require ultralight composite structures with external wire bracing. Solar cells will cover both sides of the vertical wing stabilizers and wing tips, which hinge up in daytime to capture the maximum amount of sunlight. A 15-hp electric propulsion unit drives a low-rpm, large diameter propeller; power will be derived from the solar cells diurnally, and from ...
1985-06-01
Energy Technology Data Exchange (ETDEWEB)
The aim of this research is to experimentally study the efficiency of a new-design plate collector used to heat air in a new desalination humidification-dehumidification process. In fact, in such processes, the air solar collectors work at unusual experimental parameters (forced convection, elevated air humidity, high solar irradiation). At these stressed experimental conditions, few published works are available in literature. Furthermore, the comparison of the efficiency of collectors running with normal air humidity content (about 10-20 g kg{sup -1}) and air of elevated humidity (20-50 g kg{sup -1}) have not been published to our knowledge. In the present investigation, a new air solar plate collector was designed and developed for its use in a desalination process. Moreover, a characterization of such collector was performed under different experimental conditions. The effect of different parameters, namely: the ...
2005-07-01
Irradiation hardening of reduced activation martensitic steels
International Nuclear Information System (INIS)
Irradiation response on the tensile properties of 9Cr-2W steels has been investigated following FFTF/MOTA irradiations at temperatures between 646 and 873 K up to doses between 10 and 59 dpa. The largest irradiation hardening accompanied by the largest decrease in the elongation is observed for the specimens irradiated at 646 K at doses between 10 and 15 dpa. The irradiation hardening appears to saturate at a dose of around 10 dpa at the irradiation temperature. No hardening but softening was observed in the specimens irradiated at above 703 K to doses of 40 and 59 dpa. Microstructural observation by transmission electron microscope (TEM) revealed that the dislocation loops with the a left angle 100 right angle type Burgers vector and small precipitates which were identified to be M_6C type carbides existed after the irradiation at below 703 K. As for the void formation, the average size of voids increased with increasing ...
Clinical study of p-aminobenzoic acid-N-xyloside Na in advanced cancer patients
Energy Technology Data Exchange (ETDEWEB)
Therapeutic effect of p-aminobenzoic acid-N-xyloside Na (K-247) were studied. Eleven patients with a variety of solid tumors were treated with K-247 alone. K-247 was given orally 800 mg daily for 4 weeks. As for side effect of the drug, only mild gastritis was observed in a few patients. Partial response (over 25% reduction of tumor size) with a median duration of two months was observed in 3 patients. These cases were metastatic tumor of lung from the carcinoma of thyroid, metastatic tumors of lung from the carcinoma of kidney, and mediastinal tumor. In eight patients the response was classified as no change and in one patient there was progressive disease. Thus K-247 has some therapeutic activity in patients with solid tumor. Combination therapy of irradiation and administration of K-247 were also studied. In the twelve patients receiving the combination therapy, partial response was observed in 7 ...
1982-02-01
Accretion onto Supermassive Black Holes in Quasars: Learning from Optical/UV Observations
Accretion processes in quasars and active galactic nuclei are still poorly understood, especially as far as the connection between observed spectral properties and physical parameters is concerned. Quasars show an additional degree of complexity compared to stars that is related to anisotropic emission/obscuration influencing the observed properties in most spectral ranges. This complicating factor has hampered efforts to define the equivalent of an Hertzsprung-Russel diagram for quasars. Even if it has recently become possible to estimate black hole mass and Eddington ratio for sources using optical and UV broad emission lines, the results are still plagued by large uncertainties. Nevertheless, robust trends are emerging from multivariate analysis of large spectral datasets of quasars. A firm observational basis is being laid out by accurate measurements of broad emission line properties especially ...
2006-01-01
Gene rearrangement and radiation carcinogenesis
International Nuclear Information System (INIS)
The development of leukemia and thyroid cancer is characterized by activation of the abl oncogene and ret oncogene, respectively. In order to clarify the relationship between these gene aberrations and radiation, the pro-myelogenous leukemia-derived cell line HL60 and the thyroid cancer-derived cell line 8505C, were irradiated in vitro with 100Gy of X-rays. RNA was then extracted from 10"8 cells of the respective cell lines and examined by the reverse transcription PCR method for rearrangements of abl and ret genes. Five kinds of positive bands were observed in the HL-60 cells irradiated with 100Gy of X-ray. Similarly, six positive bands were also observed in the 8505C cells irradiated with 100Gy. In vitro X-irradiation activation of oncogenes found in radiation induced cancers imply that gene rearrangement by X-rays is involved in the development of malignant tumors. Furthermore, in an experiment to ...
1993-11-01
Electronic properties of doped CuPc layers
Energy Technology Data Exchange (ETDEWEB)
Doping of molecular organic materials is important for the functionality of organic electronic devices as e.g solar cells. We investigated the doping behaviour of the acceptor molecules Cl{sub 2}-DCNQI and F{sub 16}CuPc incorporated into a CuPc matrix. In-situ XPS/UPS measurements were performed on coevaporated films. Doping by Cl{sub 2}-DCNQI was not successful. The molecule lost its chlorine atoms during thermal evaporation. For pristine F{sub 16}CuPc layers we observe a strong broadening of the photoemission features with increasing deposition rate indicating different domains probably of different molecular structure of differing electric interface potential. F{sub 16}CuPc incorporated into CuPc shows sharp photoemission features. With increasing F{sub 16}CuPc content Fermi level shifts are observed in both phases. In CuPc the maximum shift is about 0.45 eV towards the HOMO level indicating p-doping. Simultaneously the ...
2009-07-01
Decoherence, chaos, quantum-classical correspondence and the arrow of time
Energy Technology Data Exchange (ETDEWEB)
The environment - external or internal degrees of freedom coupled to the object of interest - can, in effect, monitor some of its observables. As a result, the eigenstates of these observables decohere and behave like classical states. Continuous destruction of superpositions leads to the effective environment-induced superselection (einselection), which is beginning to be recognized as a key step in the transition from quantum to classical. We investigate it here in the context of quantum chaos. I show that the evolution of a chaotic macroscopic system is not just difficult to predict (requiring accuracy exponentially increasing with time) but quickly ceases to be deterministic in principle as a result of the Heisenberg uncertainty (which limits the available resolution). This happens after a time t{sub {Dirac_h}} which is only logarithmic in the Planck constant. For example, various components of the solar system are ...
1998-12-01
Energy Technology Data Exchange (ETDEWEB)
Twenty-four patients were studied with both /sup 201/Tl-thallus chloride and /sup 99m/Tc-TBI scintigraphy following exercise. Comparison of the two agents in detecting segmental myocardial ischemia and scar was made in 18 patients with evidence of coronary artery disease on /sup 201/Tl-thallous chloride scintigraphy. Agreement between the two studies was observed in 77% (125 of 162) of left ventricular segments, suggesting that /sup 99m/Tc-TBI can be used as a myocardial perfusion agent. Limitations were related to early high background activity from lungs and liver. The high lung activity and early myocardial redistribution within the 1st hour contributed to the failure of /sup 99m/Tc-TBI to detect 16 segmental defects seen in the immediate post-exercise thallous chloride scan. Persistently high liver activity additionally affected accurate interpretation in the left ventricular segments close to the ...
1986-10-01
The seeded growth of calcium sulfate dihydrate crystals in NaCl solutions up to 6 m and 90 C
Energy Technology Data Exchange (ETDEWEB)
The kinetics of calcium sulfate crystal growth is of importance in various fields, such as geochemistry, desalination technology, petroleum industry, and water and wastewater treatment. The seeded crystal growth rate of calcium sulfate dihydrate was measured as a function of supersaturation in NaCl electrolyte solutions from 0 to 6 m at temperatures of 25, 50, 70, and 90 C. The growth followed a second-order parabolic rate law with activation energies greater than 53 kJ/mol which suggested the surface reaction as the rate-limiting step. It was observed that the rate constant and the activation energy are solution composition dependent. The rate constant increases with NaCl concentration up to 3 molal and then begins to fall slightly. The activation energy dropped from 61 kJ/mol in the pure Ca-SO[sub 4]H[sub 2]O system to 53 kJ/mol in 3.0 m NaCl solutions. The electrolyte effect was similar to the ...
1994-03-15
International Nuclear Information System (INIS)
Samples from 314 broiler chickens at 2 months age were analyzed for blood serum level of lysozyme and 311 of them were analyzed also for activity of alternative path-way of complement activity (APCA). Chickens were hatched from eggs, irradiated immediately before incubation with different doses of gamma-rays using Rocus M device - group 1 - control (non irradiated), and groups 2, 3 and 4 - irradiated with doses of 0.15, 0.30 and 0.60 Gy, respectively. Lysozyme concentration was highest for the control group, and for the experimental ones it was lower (p<0.001) which is an indication of the strongly negative effect of gamma-rays on this indicator. For APCA the oppsite relationship was observed - increasing of its activity with increasing of irradiation dose (from p<0.05 to p<0.001) which gave reason to suggest that this phenomenon is due to the irradiation. 12 refs., 2 tabs. (author).
Energy Technology Data Exchange (ETDEWEB)
In 10 cases of femoral neck fracture treated with prosthetic replacement, the preoperative sup(99m)Tc-MDP scintigraphs were investigated and then compared with each histological findings of the extracted femoral head. The appearances of the scintigraphs were classified into following 3 patterns; increased activity pattern of sup(99m)Tc-MDP uptake in the overall femoral head (type I) in 4 cases, deficient activity pattern at the lateral side correspond to weight-bearing area (type II) in 2 cases and considerably deficient activity pattern in the whole femoral head (type III) in remaining 4 cases. Histological examination of the extracted femoral heads revealed the narrow part of ischemic necrosis in type I. However type II showed extensive necrosis in the portion of deficient activity by scintigraphs and in type III, the femoral heads except articular cartilage were entirely necrotic. This classification ...
1984-06-01
Scintigraphical observation of femoral head in femoral neck fractures
International Nuclear Information System (INIS)
In IO cases of femoral neck fracture treated with prosthetic replacement, the preopera tive sup(99m)Tc-MDP scintigraphs were investigated and then compared with each histological findings of the extracted femoral head. The appearances of the scintigraphs were classified into following 3 patterns; increased activity pattern of sup(99m)Tc-MDP uptake in the overall femoral head (type I) in 4 cases, deficient activity pattern at the lateral side correspond to weight-bearing area (type II) in 2 cases and considerably deficient activity pattern in the whole femoral head (type III) in remaining 4 cases. Histological examination of the extracted femoral heads revealed the narrow part of ischemic necrosis in type I. However type II showed extensive necrosis in the portion of deficient activity by scintigraphs and in type III, the femoral heads except articular cartilage were entirely necrotic. This ...
Energy Technology Data Exchange (ETDEWEB)
Water from small scale purification plants is a low cost alternative for consumers in comparison to the bottled commercial presentations. Because of its low cost per liter, the consumption of this product has increased in recent years, stimulating in turn the installation of purification systems for these small businesses. The purpose of this study was to estimate the efficiency of small scale purification systems located in the cities of Zacatecas and Guadalupe, Zacatecas, to reduce the radioactive content of water. It was measured the total alpha and beta activity in water samples of entry and exit to process, through the liquid scintillation technique. In general it was observed that the process is more efficient in removing alpha that beta activity. The fraction of total alpha activity removed varied between 27 and 100%, while between 0 and 77% of the total beta activity was ...
2009-10-15
Cyclopropane isomerization over Eu[sup 3+]NaX zeolites
Energy Technology Data Exchange (ETDEWEB)
Cyclopropane isomerization to propylene over various Eu[sup 3+] loadings in NaX zeolite have been studied by measurements of steady-state and transient kinetics and by Fourier transform infrared spectroscopy. As Eu[sup 3+] loading increases, the rate of deactivation increases, the conversion increases, apparent activation energies are lowered, and Bronsted acid site strength and amounts increase. Apparent activation energies of 13-15 kcal/mol for propylene formation have been observed for these systems, consistent with literature reports for other metal supported heterogeneous catalyst systems. Deactivation studies have shown that activity can be restored by heating in He at 380[degrees]C between various temperature runs, and that gases desorbed during regeneration are predominantly propylene. Poisoning studies of Bronsted sites with Na vapor lead to deactivation of these catalysts. A reaction mechanism ...
1992-11-01
The aqueous fraction (AF) of an ethanolic extract from Chrysanthemum indicum was evaluated for analgesic activity in mice using chemical and thermal models of nociception. Given orally, AF at doses of 300 and 600 mg/kg produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid, subplantar formalin/capsaicin injections and on thermal nociception in the tail-flick test and in the hot plate test. In the pentobarbital sodium-induced sleeping time test and the open-field test, AF neither significantly enhanced the pentobarbital sodium-induced sleeping time nor impaired the motor performance, indicating that the observed analgesic activity was unlikely due to sedation or motor abnormality. In a measurement of core body temperature, AF did not affect temperature within 80 min. Moreover, the effective dose (600 mg/kg) also showed no toxicity within 7 days. These results suggested further that AF ...
2011-07-01
A rapid, radiometric assay for sucrose synthase
Energy Technology Data Exchange (ETDEWEB)
Investigations of sucrose synthase in maize root tips have required development of a means to circumvent the rapid decline of activity observed after extraction dialysis and either synthetic or degradative assays. Several protease inhibitors were tested; although PMSF increased initial activity, no inhibitor prevented the drop in activity with time. Western blot analysis indicated that activity decline was not associated with protein degradation. Therefore, a procedure was developed which (1) shortened extraction-to-assay period from ca. 24 hours to 7 minutes, (2) simplified previous assays and (3) reduced the amount of tissue required. Extract was desalted with spun columns and the {sup 14}C-UDPG product recovered with DEAE ion exchange paper. The minute quantities of product recovered can be concealed by the presence of trace impurities in the {sup 14}C-sucrose utilized. DEAE ion ...
1990-05-01
TIME EVOLUTION OF CORONAL MAGNETIC HELICITY IN THE FLARING ACTIVE REGION NOAA 10930
International Nuclear Information System (INIS)
To study the three-dimensional (3D) magnetic field topology and its long-term evolution associated with the X3.4 flare of 2006 December 13, we investigate the coronal relative magnetic helicity in the flaring active region (AR) NOAA 10930 during the time period of December 8-14. The coronal helicity is calculated based on the 3D nonlinear force-free magnetic fields reconstructed by the weighted optimization method of Wiegelmann, and is compared with the amount of helicity injected through the photospheric surface of the AR. The helicity injection is determined from the magnetic helicity flux density proposed by Pariat et al. using Solar and Heliospheric Observatory/Michelson Doppler Imager magnetograms. The major findings of this study are the following. (1) The time profile of the coronal helicity shows a good correlation with that of the helicity accumulation by injection through the surface. (2) The coronal helicity of the AR is estimated to ...
2010-09-10
Energy Technology Data Exchange (ETDEWEB)
Analyses of process system properties were continued for important chemical materials involved in the several processes under consideration for semiconductor and solar cell grade silicon production. Major activities were devoted to physical, thermodynamic and transport property data for silicon. Property data are reported for vapor pressure heat of vaporization, heat of sublimation, liquid heat capacity and solid heat capacity as a function of temperature to permit rapid usage in engineering. Chemical engineering analysis of the HSC process (Hemlock Semiconductor Corporation) for production of silicon was initiated. The process is based on hydrogen reduction of dichlorosilane (DCS) to produce the polysilicon. The chemical vapor deposition reaction for DCS is faster in rate than the conventional process route which utilizes trichlorosilane (TCS) as the silicon raw material. Status and progress are reported for primary ...
1980-03-01
Energy Technology Data Exchange (ETDEWEB)
This report for the Swiss Federal Office of Energy (SFOE) presents the overview reports made by SFOE Heads of Program on work done in 2007. Projects reported on in the natural gas-fired fuel cell area include the EU-project REAL-SFOC, the long-term testing of anode-supported SOFC stacks, intermediate-temperature fuel cells based on proton conducting electrolytes, the interdisciplinary ONEBAT project and lifetime-enhancement of SOFC stacks for CHP applications. In the polymer-electrolyte fuel cell (PEFC) area, projects concerning proton-conducting polymer membranes, factors limiting the lifetime of fuel cell membranes, a new highly active oxygen reduction electrode for PEM fuel cell and zinc/air battery applications, the enhancement of PEFC durability and reliability, model-based investigation of PEFC performance, and local gas analysis of PE fuel cells are briefly reported on. Long-term research activities in the hydrogen technology area ...
2008-07-01
Video and seismic observations of Strombolian eruptions at Erebus volcano, Antarctica
British Library Electronic Table of Contents (United Kingdom)
Between 1986 and 1990 the eruptive activity of Erebus volcano was monitored by a video camera with on-screen time code and recorded on video tape. Corresponding seismic and acoustic signals were recorded from a network of 6 geophones and 2 infrasonic microphones. Two hundred Strombolian explosions and three lava flows which were erupted from 7 vents were captured on video. In December 1986 the Strombolian eruptions ejected bombs and ash. In November 1987 large bubble-bursting Strombolian eruptions were observed. The bubbles burst when the bubble walls thinned to ?20?cm. Explosions with bomb flight-times up to 14.5?s were accompanied by seismic signals with our local size estimate, ?unified magnitudes?? (mu), up to 2.3. Explosions in pools of lava formed by flows in the Inner Crater were co...
2008-01-01
Understanding the volatility smile of options markets through microsimulation
In this work, we aim to gain a better understanding of the volatility smile observed in options markets through microsimulation (MS). We adopt two types of active traders in our MS model: speculators and arbitrageurs, and call and put options on one underlying asset. Speculators make decisions based on their expectations of the asset price at the option expiration time. Arbitrageurs trade at different arbitrage opportunities such as violation of put-call parity. Difference in liquidity among options is also included. Notwithstanding its simplicity, our model can generate implied volatility (IV) curves similar to empirical observations. Our results suggest that the volatility smile is related to the competing effect of heterogeneous trading behavior and the impact of differential liquidity.
2007-01-01
Spatial fluorescence cross correlation spectroscopy by means of a spatial light modulator
Spatial Fluorescence Cross Correlation Spectroscopy is a rarely investigated version of Fluorescence Correlation Spectroscopy, in which the fluorescence signals from differ-ent observation volumes are cross-correlated. In the reported experiments, two observation volumes, typically shifted by a few $\\mu$m, are produced, with a Spatial Light Modulator and two adjustable pinholes. We illustrated the feasibility and potentiality of this technique by: i) measuring molecular flows, in the range 0.2 - 1.5 $\\mu$m/ms, of solutions seeded with fluorescent nanobeads or rhodamine molecules (simulating active transport phenomenons); ii) investigating the perme-ability of phospholipidic membrane of Giant Unilamellar Vesicles versus hydrophilic or hydrophobic molecules (in that case the laser spots were set on both sides of the mem-brane). Theoretical descriptions are proposed together with a discussion about FCS based, alternative ...
2008-01-01
International Nuclear Information System (INIS)
Ozone is a principal component of photochemical air pollution endogenous to numerous metropolitan areas. It is primarily formed by the oxidation of NOx in the presence of sunlight and reactive organic compounds. Ozone is a highly active oxidizing agent capable of causing injury to the lung. Lung injury may take the form of irritant effects on the respiratory tract that impair pulmonary function and result in subjective symptoms of respiratory discomfort. These symptoms include, but are not limited to, cough and shortness of breath, and they can limit exercise performance. The effects of ozone observed in humans have been primarily limited to alterations in respiratory function, and a range of respiratory physiological parameters have been measured as a function of ozone exposure in adults and children. These affects have been observed under widely varying (clinical experimental and environmental settings) conditions
1994-07-01
International Nuclear Information System (INIS)
Synergism has been observed during inhibiting initiated oxidation of styrene or tetralin by organic phosphites in the presence of complex compounds of some transition metals. The results are given of non-additive intensification of antioxidative activity of triphenylphosphite (TPP) and tri-(4-methyl-6-tert.-- butyl)-phenyl-phosphite (TMBP) in the process of initiated oxidation of styrene or tetralin with addition of acetylacetonates of cobalt and vanadyl. During styrene oxidation, inhibition of the reaction with chelate complex of vanadyl is weakened considerably when phosphite is added into the reaction system. During tetralin oxidation, postcatalytic (or branched) oxidation is observed only for large concentration of vanadyl complex. Addition of TPP to above complex sharply increases the induction period. When the induction period is completed, oxidation of tetralin follows the mechanism of usual, i.e. initiated, ...
Energy Technology Data Exchange (ETDEWEB)
In order to promote environmental damage monitoring and environmental impacts assessment caused by mining in China, the most significant project that uses advanced Earth Observation technology to assess environmental impacts caused by mining, namely MINEO (assessment and monitoring the environmental impact of mining activities in Europe using advanced Earth Observation technology) was introduced and its enlightenment to China were investigated. It was proposed that an integrated technical framework of monitoring environmental impacts caused by mining be designed, quantitative inversion of biological and environmental parameters from RS data be emphasised, hyperspectral Remote Sensing be applied, RS and GIS be integrated with professional models, multi-object applications of RS be implemented, and related standards and specification be drawn up based on typical case study sites. 23 refs., 1 fig.
2008-01-15
International Nuclear Information System (INIS)
The Monte-Carlo method and experimental methods were used to determine the neutron fluxes in the irradiation channels of the Ghana Research Reactor -1. The MCNP5 code was used for this purpose to simulate the radial and axial distribution of the neutron fluxes within all the ten irradiation channels. The results obtained were compared with the experimental results. After the MCNP simulation and experimental procedure, it was observed that axially, the fluxes rise to a peak before falling and then finally leveling out. Axially and radially, it was also observed that the fluxes in the centre of the channels were lower than on the sides. Radially, the fluxes dip in the centre while it increases steadily towards the sides of the channels. The results have shown that there are flux variations within the irradiation channels both axially and radially. (au)
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
Examination is made of the main features of the physical and chemical preignition processes within homogeneous mixtures of air and gaseous fuels, such as propane, methane and hydrogen in a motored engine, while employing detailed chemical kinetics in a one zone analytical model. The changes in the compression temperature and pressure due to the admission of gaseous fuels, energy release during the preingition reactions and the contributions of heat transfer and residual gases to the preignition reaction activity were followed over a number of consecutive cycles until the occurrence of autoignition. Some of the observed differences in engine behaviour when operating on methane, propane and hydrogen were discussed with particular reference to the observed trends in dual fuel engine operation. Calculated results showed good agreement with some corresponding experimental trends. 14 refs., 9 figs.
1994-10-01
Energy Technology Data Exchange (ETDEWEB)
The growth of the Pd{sub 2}Si thin fllms on Si(111) substrates has been monitored by an {ital in} {ital situ} x-ray diffraction technique in vacuum and in helium atmosphere from 160 to 250 {degree}C. A familiar parabolic growth rate was found, confirming the diffusion-controlled film growth process. The activation energies were found to be 1.34 and 1.37 eV for the measurements performed in vacuum and helium environment, respectively. Stress relaxation in the growing Pd{sub 2}Si fllm was observed when the reaction temperature exceeds 200 {degree}C. The relaxed films showed a higher degree of texture as evidenced by the rocking curve measurements.
1990-04-15
The growth of the Pd{sub 2}Si thin fllms on Si(111) substrates has been monitored by an {ital in} {ital situ} x-ray diffraction technique in vacuum and in helium atmosphere from 160 to 250 {degree}C. A familiar parabolic growth rate was found, confirming the diffusion-controlled film growth process. The activation energies were found to be 1.34 and 1.37 eV for the measurements performed in vacuum and helium environment, respectively. Stress relaxation in the growing Pd{sub 2}Si fllm was observed when the reaction temperature exceeds 200 {degree}C. The relaxed films showed a higher degree of texture as evidenced by the rocking curve measurements.
1990-04-15
International Nuclear Information System (INIS)
A study on the distribution of "1"3"7Cs in coastal waters up to a distance of 15 km was undertaken for a decade (1995-2004) and observed that the activity has reduced by 15-20 fold. Statistical and trend analysis was carried out to resolve the contribution of different facilities at a distance of 5 km (north and south) from the discharge point by log normal probability analysis and found that at 5 km south, the median value of "1"3"7Cs due to TAPS and FRP discharges were 3.7 mBq/l and 1.50 mBq/l respectively. The observed levels of "1"3"7Cs are of no consequences from the point of view of dose to members of the public. (author)
2005-11-23
["3H]Indole-3-acetyl-myo-inositol hydrolysis by extracts of Zea mays L. vegetative tissue
International Nuclear Information System (INIS)
["3H]Indole-3-acetyl-myo-inositol was hydrolyzed by buffered extracts of acetone powders prepared from 4 day shoots of dark grown Zea mays L. seedlings. The hydrolytic activity was proportional to the amount of extract added and was linear for up to 6 hours at 37"0C. Boiled or alcohol denatured extracts were inactive. Analysis of reaction mixtures by high performance liquid chromatography demonstrated that not all isomers of indole-3-acetyl-myo-inositol were hydrolyzed at the same rate. Buffered extracts of acetone powders were prepared from coleoptiles and mesocotyls. The rates of hydrolysis observed with coleoptile extracts were greater than those observed with mesocotyl extracts. Active extracts also catalyzed the hydrolysis of esterase substrates such as #alpha#-naphthyl acetate and the methyl esters of indoleacetic acid and naphthyleneacetic acid. Attempts to purify the indole-3-acetyl-myo-inositol ...
Kelvin-day function for climatic solar heating design
Energy Technology Data Exchange (ETDEWEB)
A method of Kelvin-day function for climatic solar heating design is presented. The long term temperature distribution is used to find the solar fraction for building heating. A solar heating system is considered to provide heat needed up to an auxiliary heater cut-in temperature which is determined by both heat gain of solar heating system and overall heat loss coefficient of the building. The amount of auxiliary heat needed is calculated from a Kelvin-day value at this cut-in temperature. The cut-in temperature will change from different solar heating system designs, and the Kelvin-day value at this cut-in temperature will be varied. By using the numerical curve-fitting method, the Kelvin-day value at any temperature base can be expressed into a second order algebraic equation, thus, the whole data need not be put into computer storage. It will be very convenient to determine the ...
1981-01-01
Stimulation of Erwinia sp. fumarase and aspartase synthesis by changing medium components.
The optimal concentrations of nutrient medium components, aeration conditions, and pH providing for maximum biomass yields, as well as fumarase and L-aspartase activities, during submerged cultivation of Erwinia sp. were determined. The data showed that different concentrations of carbon source (molasses) and pH of the nutrient medium were required to reach the maximum fumarase and L-aspartase activities. Calculations performed by application of the additive lattice model suggested that the combination of these optimized factors would result in 3.2-, 3.4-, and 3.8-fold increases as compared to the experimental means in Erwinia sp. biomass, and L-aspartase and fumarase activities, respectively. The conditions of the fumaric acid biotransformations into L-malic and L-aspartic acids were optimized on the basis of intact Erwinia sp. cells, a fumarase and L-aspartase producer. In the cases of fumarate transformation into L-malic ...
2005-05-01
International Nuclear Information System (INIS)
The objective was to study the brain areas which are activated when normal subjects make moral judgments. Ten normal adults underwent BOLD functional magnetic resonance imaging (fMRI) during the auditory presentation of sentences that they were instructed to silently judge as either 'right' or 'wrong'. Half of the sentences had an explicit moral content ('We break the law when necessary'), the other half comprised factual statements devoid of moral connotation ('Stones are made of water'). After scanning, each subject rated the moral content, emotional valence, and judgment difficulty of each sentence on Likert-like scales. To exclude the effect of emotion on the activation results, individual responses were hemo dynamically modeled for event-related f MRI analysis. The general linear model was used to evaluate the brain areas activated by moral judgment. Regions activated during moral judgment included ...
2001-09-01
Background: Protein disulfide isomerase (PDI) controls platelet integrin function, tissue-factor (TF) activation, and concentrates at fibrin and thrombus formation sites of vascular injury. Objective: We investigated involvement of surface thiol isomerases and especially PDI, in thrombin-mediated thrombin amplification on human platelets. Methods/Results: Using a new developed thrombin-dependent platelet thrombin generation assay we observed that the feedback activation of thrombin generation on the platelet surface does not depend on TF, as anti-TF antibodies inhibiting TF-induced thrombin formation in platelet-depleted plasma had no effect compared to vehicle-treated controls. Feedback activation of thrombin generation in the presence of platelets was significantly diminished by membrane impermeant thiol blockers or by the thiol isomerase-inhibitors bacitracin and anti-PDI antibody RL90, respectively. ...
2011-09-19
Based on a collisional-radiative model, an atomic-kinetic calculation of the gains on the 41.8-nm transitions of Pd-like xenon was performed for the plasma produced due to the interaction of a femtosecond laser pulse with gaseous xenon. The gains g(z,{tau}) averaged over the spatial and temporal coordinates were compared with the known gains which had been measured experimentally in Xe{sup 8+}. The amplification was shown to occur under the conditions of ionisation of the working ions, and the time of output radiation saturation depends on the time of Xe{sup 8+} transformation to higher-ionised ions. Our theoretical investigation enables determining the optimal pump parameters, at which the product of the gain g by the active medium length L is about 20, which exceeds the experimental gL value. (active media)
2004-11-30
International Nuclear Information System (INIS)
Based on a collisional-radiative model, an atomic-kinetic calculation of the gains on the 41.8-nm transitions of Pd-like xenon was performed for the plasma produced due to the interaction of a femtosecond laser pulse with gaseous xenon. The gains g(z,?) averaged over the spatial and temporal coordinates were compared with the known gains which had been measured experimentally in Xe8+. The amplification was shown to occur under the conditions of ionisation of the working ions, and the time of output radiation saturation depends on the time of Xe8+ transformation to higher-ionised ions. Our theoretical investigation enables determining the optimal pump parameters, at which the product of the gain g by the active medium length L is about 20, which exceeds the experimental gL value. (active media)
2004-11-30
The influence of ultrasound on the fluoroquinolones antibacterial activity
British Library Electronic Table of Contents (United Kingdom)
In this work, the antibacterial effect of fluoroquinolones (FQs) upon Escherichia coli (E.coli) was measured with and without application of 40kHz ultrasound (US) stimulation. The research results demonstrated that simultaneous application of 40kHz US apparently enhanced the antibacterial effectiveness of FQs. That is, the synergistic effect was observed and the bacterial viability was reduced when FQs and US were combined. In addition, various influencing factors, such as FQs drug concentration, US irradiation time and solution temperature, on the inhibition of E.coli were also investigated. The antibacterial activity was enhanced apparently with increasing of FQs drug concentration, US irradiation time and solution temperature. Furthermore, we discussed preliminarily the mechanism of US ...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
We revisit a recently proposed agent-based model of active biological motion and compare its predictions with own experimental findings for the speed distribution of bacterial cells, Salmonella typhimurium. Agents move according to a stochastic dynamics and use energy stored in an internal depot for metabolism and active motion. We discuss different assumptions of how the conversion from internal to kinetic energy d(v) may depend on the actual speed, to conclude that d 2 v ? with either ? = 2 or 1 ? < 2 are promising hypotheses. To test these, we compare the model?s prediction with the speed distribution of bacteria which were obtained in media of different nutrient concentration and at different times. We find that both hypotheses are in line with the experimental observations, with ? bet...
2011-01-01
Sucrose accumulation in mature sweet melon fruits. [Cucumis melo
Energy Technology Data Exchange (ETDEWEB)
Mesocarp tissue from sucrose-accumulating sweet melon (Cucumis melo cv. Galia) showed sucrose synthase activity (ca 1 nkat/gfw) while soluble acid invertase and sucrose phosphate synthase activities were not observed. Sucrose uptake into mesocarp discs was linear with sucrose concentration (1-500 mM) and unaffected by PCMBS and CCCP. Sucrose compartmentation into the vacuole also increased linearly with sucrose concentration as indicated by compartmental efflux kinetics. Mesocarp discs incubated in /sup 14/C-fructose + UDP-glu synthesized /sup 14/C-sucrose and efflux kinetics indicated that the /sup 14/C-sucrose was compartmentalized. These data support the hypothesis that two mechanisms are involved in sucrose accumulation in sweet melon: (1) compartmentation of intact sucrose and (2) synthesis of sucrose via sucrose synthase and subsequent compartmentation in the vacuole.
1987-04-01
Spatio-temporal variation of vegetation in an arid and vulnerable coal mining region
British Library Electronic Table of Contents (United Kingdom)
Environmental assessment in an arid coal mining area requires an understanding of the influences of coal mining, the arid climate and ecological remediation. To that end, we selected vegetation as the key environmental factor to observe. Remote sensing approaches to monitoring the spatio-temporal variation of vegetation caused by mining activities, the arid climate and ecological remediation in the Shengdong coal mining area are described. Over a large regional scale it was found that the vegetation was improved as a result of ecological remediation activities. At the local scale, however, the vegetation coverage and soil moisture in the mined areas were slightly lower than those in un-mined areas due to mining subsidence. These differences are partly attributed to ground fissures that inj...
2010-01-01
Septal stimulation inhibits spinal cord dorsal horn neuronal activity
British Library Electronic Table of Contents (United Kingdom)
Deep brain stimulation (DBS) has been used for relieving chronic pain in patients that have been through other existing options. The septum has been one of the targets for such treatment. The purpose of this study was to determine the inhibitory effect of electrical stimulation in the medial septum diagonal band of broca (MSDB) on neuronal activity in the spinal cord of rats anesthetized with sodium pentobarbital. While unilaterally stimulating the MSDB, wide dynamic range neurons in the lumbar region of the spinal cord were recorded in response to graded mechanical stimulation of the hind paws (brush, pressure, and pinch). Stimulation was at 1, 5, 10, and 20V, at 100Hz, and 0.1ms duration. Significant bilateral reduction was observed in response to pressure (ipsilaterally: 0.90+/-0.05, 0....
2011-01-01
Radiation protection and the role of TSOs in Kenya
International Nuclear Information System (INIS)
Since the late '60s and through the early '90s Kenya has always recognized and appreciated the need for support from Technical and Scientific Support Organizations (TSOs) for activities geared towards enhancing nuclear and radiation safety. The TSOs have since then gained increasing importance for provision of technical and scientific basis for policy formulation, implementation and legislation with regard to radiation safety. National and specific operator programmes on safety and security of radiation source and radioactive waste recognize and encourage the active participation of TSOs. Due to the role they play, technical competence, transparency and the observance of ethical practices have become essential both for the regulator and the regulated. In this respect, interaction and cooperation between stake holders (regulatory authorities, users of radiation, generators of radioactive waste, professional organizations) ...
2007-08-01
Measurement of induced radioactivity in materials found around a neutron generator
The induced radioactivity in the construction materials of a Cockcroft-- Walton type neutron generator was measured. Major activation products (/sup 24/ Na, /sup 28/Al, /sup 56/Mn, /sup 64/Cu, /sup 65/Ni, /sup 69m/Zn, /sup 88/Rb /sup 91/Sr /sup 101/Mo, /sup 187/W/ and resulting doses are tabulated. Results show that the highest gamma activities would be observed in the fluorescent bulbs, copper pipe, aluminum lattice rod, and the aluminum pipe clamp. Thermoluminescent dosimeter readings yield the highest doses for the copper pipe tee, copper pipe, and aluminum lattice rod. Results of measuremerts of the neutron and gamma dose profiles of the facility are shown. However the indication is clearly that the tritium target, compared to other components, is the major source of radiation both during and after shutdown. (UK)
1974-01-01
Investigation of Hg volatile losses from samples and standards during neutron activation analysis
International Nuclear Information System (INIS)
The losses of Hg from phenol formaldehyde resin - bound standards and hair samples in neutron activation analysis in case of their irradiation in the water filled nuclear reactor channel is studied. The mean losses of Hg during 20-30 hrs irradiation at (2-3)x10"1"8 n/cm"2 are 15-20% with their stopping at double Al-covers. The mean losses of Hg from standards at 200, 250 and 300 deg C are 30, 61 and 86% respectively and do not occur at 150 deg C after their 5 hour heating. The losses of Hg from hair samples packed in polyethylene tubes through the package walls in experimental conditions are not observed.
Impregnation of silver nanoparticles into bacterial cellulose for antimicrobial wound dressing
British Library Electronic Table of Contents (United Kingdom)
Bacterial cellulose was produced by Acetobacter xylinum (strain TISTR 975). Bacterial cellulose is an interesting material for using as a wound dressing since it provides moist environment to a wound resulting in a better wound healing. However, bacterial cellulose itself has no antimicrobial activity to prevent wound infection. To achieve antimicrobial activity, silver nanoparticles were impregnated into bacterial cellulose by immersing bacterial cellulose in silver nitrate solution. Sodium borohydride was then used to reduce the absorbed silver ion (Ag+) inside of bacterial cellulose to the metallic silver nanoparticles (Ag0). Silver nanoparticles displayed the optical absorption band around 420nm. The red-shift and broadening of the optical absorption band was observed when the mole rat...
2008-01-01
GREEN TEA PHENOLS INTERFERENCE IN THE GLUCOSE OXIDASE/PEROXIDASE TEST
British Library Electronic Table of Contents (United Kingdom)
Abstract Green tea extract showed false-negative results in the determination of glucose via glucose oxidase (GOD) test. This investigation was undertaken to verify and find out the precise mechanism underlying this interference by determining the reaction kinetics of production and reduction of end-point chromophore. The peroxidase step of the GOD test was found to be interfered and phenols of the green tea were the interfering compounds. Green tea interfered and exerted its influence in a dual fashion. A part of the interference was observed as a result of the reduction of the finally formed chromophore, whereas the other form of interference was due to its hydrogen peroxide/free radical-scavenging activity. Reducing potential and the free radical-scavenging activity of the phenols in th...
2011-01-01
Exploring the patterns and causes of land use changes in south-west Sweden
British Library Electronic Table of Contents (United Kingdom)
To study the causes of agricultural declines in south-west Sweden, a multi-proxy study including pollen analysis, bog surface wetness indicators and aeolian sediment influx reconstructions was carried out on the Store Mosse Bog, situated on the coastal plain of Halland. Patterns of agricultural changes during the past 6,000?years from this study were compared to one additional site on the coastal plain (Undarsmosse Bog) and to four sites in the forested upland region. First, we compared land use activity on the coastal plain and in upland regions of south-west Sweden. Three periods with reduced agricultural activities were observed, primarily in records from the coastal plain. Next, the causes for these declines were studied by comparing land use indicators in the pollen records from the S...
2011-01-01
Enhanced antibacterial activity of bifunctional Fe3O4-Ag core-shell nanostructures
British Library Electronic Table of Contents (United Kingdom)
We describe a simple one-pot thermal decomposition method for the production of a stable colloidal suspension of narrowly dispersed superparamagnetic Fe3O4-Ag core-shell nanostructures. These biocompatible nanostructures are highly toxic to microorganisms. Antimicrobial activity studies were carried out on both Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus megaterium and Staphylococcus aureus) bacterial strains. Efforts have been made to understand the underlying molecular mechanism of such antibacterial actions. The effect of the core-shell nanostructures on Gram negative strains was found to be better than that observed for silver nanoparticles. The minimum inhibitory concentration (MIC) values of these nanostructures were found to be considerably lowe...
2009-01-01
British Library Electronic Table of Contents (United Kingdom)
The endophytic fungus Trichothecium roseum LZ93 from Maytenus hookeri was found to antagonize other pathogenic fungi in vitro. To identify which compound contributed substantially to the antagonism, we fermented the strain and purified its fermentation products. Eleven compounds were obtained, including two trichothecenes, five rosenonolactones, two cardiotonic cyclodepsipeptides, and two sterols. Compound 11?-hydroxyrosenonolactone (1) was assigned according to 1D and 2D-NMR data for the first time. At the same time, the 1H and 13C-NMR assignments for 6?-hydroxyrosenonolactone (2) were revised. Of all of them, only trichothecin (6) showed strong antifungal activity. Based on our observations of the antagonistic activity and the other experimental results, we suggest that the antifungal co...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
This study describes the effect of treatment of Bis(3-triethoxysilyl propyl)tetrasulfane (silane coupling agent, Si69, TESPT) on in situ sodium activated, organo modified bentonite clay - styrene butadiene rubber (SBR) nanocomposite. transmission electron microscopy and Wide angle X-ray diffraction indicated the intercalation as well as partial exfoliation in both the organoclay and silane treated organoclay compound. It was found that about 5% of silane with respect to clay was the optimum dose for the treatment. Around 15% improvement in tensile and tear strength was observed due to silane treatment. Silane treated organoclay exhibited substantial improvement of the fatigue life, compression set, and rebound property. A detailed study of physical property was carried out. A comparison wi...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then trow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs grain size shows a plateau for grains below critical size : these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected from the Yangsan fault system. ESR dates from the this fault system range from 870 to 240 ka. Results of this research suggest that long-term cyclic fault activity continued into the pleistocene.
2002-03-15
Development of Ultra-Fast Silicon Switches for Active X-Band High Power RF Compression Systems
Energy Technology Data Exchange (ETDEWEB)
We present the recent results of our research on the high power ultra-fast silicon RF switches. This switch is composed of a group of PIN diodes on a high purity silicon wafer. The wafer is inserted into a cylindrical waveguide under TE{sub 01} mode, performing switching by injecting carriers into the bulk silicon. Our current design uses a CMOS compatible process and the device was fabricated at SNF (Stanford Nanofabrication Facility). 300 ns switching time has been observed, while the switching speed can be improved further with 3-D device structure and faster driving circuit. Power handling capacity of the switch is at the level of 10 MW. The switch was designed for active X-band RF pulse compression systems--especially for NLC, but it is also possible to be modified for other applications and other frequencies.
2006-03-06
Determination of radon and thoron permeability through some plastics by track technique
Energy Technology Data Exchange (ETDEWEB)
Experiments have been performed to study the usefulness of several types of plastic foils as filter to separate radon and thoron. Time-integrated alpha-activity measurements have been carried out by using the so-called ''can-technique'' equipped with both LR-115 and CR-39 track detectors. The track density observed on the detectors, taken as a measure of radon activity concentration, has been determined as a function of the thickness of filter foils. The radon permeability and the thoron separation factors have been determined. It is shown that various plastic foils exhibit considerable differences in radon diffusion coefficient owing to their different chemical structures. Among the plastic foils investigated the polyethylene proved to have the highest gas diffusion coefficient.
1986-01-01
An improved noise-robust voice activity detector based on hidden semi-Markov models
British Library Electronic Table of Contents (United Kingdom)
To improve the performance of voice activity detector (VAD) in noisy environments, this paper concentrates on three critical aspects related to noise robustness including speech features, feature distributions and temporal dependence. Based on the statistic on TIMIT and NOIZEUS, Mel-frequency cepstrum coefficients (MFCCs) are selected as speech features, Gaussian Mixture distributions (GMD) are applied to associate the observations in MFCC domain with both speech and non-speech states, and Weibull and Gamma distributions are used to explicitly model noise and speech durations, respectively. To integrate these aspects into VAD, the hidden semi-Markov model (HSMM) as a generalized hidden Markov model (HMM) is introduced first. Then the VAD decision is made according to the likelihood ratio t...
2011-01-01
Adsorption of hexavalent chromium from aqueous solution by using activated red mud
Energy Technology Data Exchange (ETDEWEB)
Adsorption by activated red mud (ARM) is investigated as a possible alternative to the conventional methods of Cr(VI) removal from aqueous synthetic solutions and industrial effluents. Adsorption characteristics suggest the heterogenous nature of the adsorbent surface sites with respect to the energy of adsorption. Various factors such as pH, contact time, Cr(VI) concentration, amount of adsorbent, and temperature are taken into account, and promising results are obtained. The applicability of the Langmuir as well as Freundlich adsorption isotherms for the present system is tested. The loading factor (i.e., milligrams Cr(VI) adsorbed per gram of ARM) increased with initial Cr(VI) concentration, whereas a negative trend was observed with increasing temperature. The influence of the addition of anions on the adsorption of Cr(VI) depends on the relative affinity of the anions for the surface and the relative concentrations of the anions.
1999-09-01
A simple model for AGN feedback in nearby early-type galaxies
British Library Electronic Table of Contents (United Kingdom)
Abstract Recent work (Schawinski et al.) indicates that star-forming early-type galaxies residing in the blue cloud migrate rapidly to the red sequence within around a Gyr, passing through several phases of increasingly strong active galactic nucleus (AGN) activity in the process. We show that natural depletion of the cold gas reservoir through star formation (i.e. in the absence of any feedback from the AGN) induces a blue-to-red reddening rate that is several factors lower than that observed by Schawinski et al. This is because the gas depletion rate due to star formation alone is too slow, implying that another process needs to be invoked to remove cold gas from the system and accelerate the reddening rate. We develop a simple phenomenological model, in which a fraction of the AGN-s lum...
2011-01-01
A radon anomaly in soil gas at Cazzaso, NE Italy, as a precursor of an M_L = 5.1 earthquake
International Nuclear Information System (INIS)
At Cazzaso (Friuli) in northeast Italy, radon ("2"2"2Rn) activity concentration in soil gas in a borehole at a depth of 80 cm has been monitored continuously (at a frequency of once an hour) since May 2004, using a Barasol probe (Algade, France). In addition, environmental parameters (air and soil temperature, barometric pressure) have been recorded. The results have been evaluated and the relationship between radon levels and seismic activity is discussed. Correlation between radon concentration and barometric pressure has been observed. Preliminary results have shown a distinct radon anomaly prior to some earthquakes. (authors)
2009-05-10
British Library Electronic Table of Contents (United Kingdom)
A new microbial transglutaminase (MTGase or MTG, EC 2.3.2.13) from a Streptomyces sp. strain isolated from Brazilian soil samples was characterized in crude and purified forms. The aim of this work is to provide relevant information about a new transglutaminase and to compare its characteristics with the well-known commercial transglutaminase from Ajinomoto Co. Inc. (Activa? TG-BP). The enzyme from Streptomyces sp., in both crude and pure forms, exhibited optimal activity in the 6.0?6.5 pH range and at 35?40?C. The results for the commercial enzyme were the same. A second maximum of activity was observed at pH?10.0 with both the crude Streptomyces sp. enzyme and the commercial enzyme. This interesting fact has not been reported in the literature previously. The fact that this second maximu...
2010-01-01
International Nuclear Information System (INIS)
The tissue distribution of "1"3"1I-transferrin ("1"3"1I-Tf) was studied in athymic nude mice having s.c. human colonic adenocarcinoma HT-29 xenografts. Four days after "1"3"1I-Tf injection, the "1"3"1I specific activity measured in the HT-29 tumor, i.e. amount of radioactivity per gram of fresh tissue, represented 0.31 #+-# 0.09% of the injected radioactivity and was 1.90 fold more than that measured in the murine colon (P < 0.05). After correction for intravascular "1"3"1I-Tf as estimated by mean of "9"9"mTc-Sn in vivo labeling of red blood cells, the "1"3"1I specific activity observed in the HT-29 tumor was 7.21 fold more than that observed in the murine colon. This subtracting method enabled us to localize a HT-29 tumor xenograft by #gamma# scintigraphy of the entire animal and demonstrated that "1"3"1I-Tf could be a non-specific but potent marker for human colon cancer. (author).
Recent Progress in the Growth of Mid-Infrared Emitters by Metal-Organic Chemical Vapor Deposition
We report on recent progress and improvements in the metal-organic chemical vapor deposition (MOCVD) growth of mid-infrared lasers and using a high speed rotating disk reactor (RDR). The devices contain AlAsSb active regions. These lasers have multi-stage, type I InAsSb/InAsP quantum well active regions. A semi-metal GaAsSb/InAs layer acts as an internal electron source for the multi-stage injection lasers and AlAsSb is an electron confinement layer. These structures are the first MOCVD multi-stage devices. Growth in an RDR was necessary to avoid the previously observed Al memory effects found in conventional horizontal reactors. A single stage, optically pumped laser yielded improved power (greater than 650 mW/facet) at 80K and 3.8um. A multi-stage 3.8-3.9um laser structure operated up to T=170K. At 80K, peak power greater than 100mW and a high slope- efficiency were observed in gain guided lasers.
1998-01-01
Fixed time and fixed point observation of environmental radioactivities in Tokyo
Energy Technology Data Exchange (ETDEWEB)
A measurement of environmental radioactivity in Tokyo was started from 1974. We have been executing fixed time and fixed point observation since 1983 in Tokyo continuously. Measurement item is rain water, airborne dust, activated sludge at sewage treatment plants and external dose rate. Measurement data from 1983 to 1995 is reported in this paper. Moreover, we have been carried out the measurement of radon concentration in air from 1988 to 1991 in different types of residental buildings. The measurement results of rain water, airborne dust, external dose rate were approximately a background level respectively except for the Chernobyl nuclear power plant accident. Radionuclides used as radiopharmaceuticals were detected in the activated sludge at every sewage treatment plant but its concentration was lower than concentration limit in Japan. From a result of radon concentration measurements, there were no place which exceeds ...
1997-03-01
Energy Technology Data Exchange (ETDEWEB)
The authors investigate the optimisation of solar-heated cavity receivers in which solar energy collected by a paraboloid collector is converted into electrical energy. The focussed solar energy enters the receiver through an aperture to heat the working fluid, which flows inside the receiver tubes and is compressed by the compressor of a gas turbine system, to the highest process temperature. A method of calculating the distribution on the inner receiver surfaces of the solar radiation reflected by the paraboloid collector is presented to begin with. The interchange of radiant energy inside the receiver cavity can be calculated on this basis, including the radiation loads, the temperatures of the inner receiver walls, and the radiative and convective losses. The temperature fields in the tube walls must be known for determining the strength required of receiver tubes; they can be derived from the ...
1984-01-01
High-efficiency solar cell and method for fabrication
A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction ...
1999-08-31
Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in the Corning design, whereas heat is conducted through a single glass wall to an external heat exchanger plate in the Philips collector. In comparison with conventional flat-plate collectors, both types show reduced heat losses and improved efficiency. For space heating and hot water supply in winter, the solar delivery efficiency of the Corning collector ranged from 49% to 60% of the incident solar energy. The ...
1979-01-01
A partitioned central solar receiver
International Nuclear Information System (INIS)
Else of solar energy as substitute for conventional fuels at a competitive cost requires efficient conversion from solar radiation to usable forms of energy. In solar thermal or thermochemical applications, high efficiency usually re- quires high temperature and high concentration of incoming radiation. The main form of energy loss from high temperature solar central receivers is thermal emission ('re radiation'), at an effective temperature close to the maximum receiver temperature. This loss is reduced if the aperture is divided into segments, most of which are maintained at lower temperatures. A two-stage partitioned receiver demonstrating this concept is under construction at the Weizman Solar Tower. The high-temperature stage is the DIAPR (Directly Irradiated Annular Pressurized Receiver). The low-temperature stage is made of tubular cavity receivers of simpler design. ...
1996-05-01
Energy Technology Data Exchange (ETDEWEB)
The National Center for Photovoltaics sponsored the 15th Workshop on Crystalline Silicon Solar Cells & Modules: Materials and Processes, held in Vail, CO, August 7-10, 2005. This meeting provided a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. The workshop addressed the fundamental properties of PV silicon, new solar cell designs, and advanced solar cell processing techniques. A combination of oral presentations by invited speakers, poster sessions, and discussion sessions reviewed recent advances in crystal growth, new cell designs, new processes and process characterization techniques, and cell fabrication approaches suitable for future manufacturing demands. The theme of this year's meeting was 'Providing the Scientific Basis for Industrial Success.' Specific sessions during ...
2005-11-01
Thermal degradation and crystallisation studies of reactively compatibilised polymer blends
British Library Electronic Table of Contents (United Kingdom)
The thermal degradation and crystallisation behaviours of polyamide12/isotactic polypropylene (PA12/PP) blends were studied. Effects of blend ratio and compatibiliser concentration on the thermal degradation properties of the blends were analysed. The activation energy for degradation in compatibilised and uncompatibilised blends computed using Horowitz-Metzger equation was reported. The blend ratio as well as the presence of compatibiliser has significant effect on the thermal stability of the blends. Phase morphology was found to be one of the decisive factors that affected the thermal stability of both uncompatibilised and compatibilised blends. Melting and crystallisation behaviours of the blends in the presence and absence of compatibiliser were evaluated. It was observed that blendin...
2008-01-01
Sunyaev-Zel'dovich Effects from Quasars Shining in Galaxies and Groups
The energy fed by active galactic nuclei to the surrounding diffuse baryons changes the latter's amount, temperature, and distribution; so in groups and in member galaxies it affects the X-ray luminosity and also the Sunyaev-Zel'dovich effect. Here we compute how the latter is enhanced by the transient blastwave driven by a shining quasar, and is depressed when the equilibrium is recovered with a depleted density. We constrain such depressions and enhancements with the masses of relic black holes in galaxies and the X-ray luminosities in groups. We discuss how all these linked observables can tell the quasar contribution to the thermal history of the baryons pervading galaxies and groups.
2003-01-01
Partial oxidation of 2-propanol on perovskites
Energy Technology Data Exchange (ETDEWEB)
Partial oxidation of 2-propanol was carried out on AB{sub 1-x}B`{sub x}O{sub 3} (A=Ba, B=Pb, Ce, Ti; B`=Bi, Sb and Cu) type perovskite oxides. Acetone was the major product observed on all the catalysts. All the catalysts underwent partial reduction during the reaction depending on the composition of the reactant, nature of the B site cation and the extent of substitution at B site. The catalytic activity has been correlated with the reducibility of the perovskite oxides determined from Temperature Programmed Reduction (TPR) studies. (orig.)
1998-12-31
Orthophosphoric acid interactions with ultrastable zeolite Y: Infrared and NMR studies
Energy Technology Data Exchange (ETDEWEB)
Zeolite Y is the active component of most commercial cracking catalysts. Interaction of H[sub 3]PO[sub 4] with extraframework aluminum of ultra-stable zeolite (USY) leads to the formation of different types of aluminum phosphates, while there is no indication of the formation of SAPO zeotype structures. The total acidity of USY slightly decreases upon the H[sub 3]PO[sub 4] treatment, while the maximum in the distribution of acid strength is shifted to milder acidities. Dealumination of the zeolite and creation of POH sites associated with AIPO[sub 4] are responsible for the modifications observed. 37 refs., 8 figs., 3 tabs.
1994-01-01
Neutron activation analysis of trace elements in Japanese hormesis cosmetics
International Nuclear Information System (INIS)
In Japan, cosmetics claiming hormesis effect are available through Internet. Although these cosmetics show the contents, they never mention the minor elements and radioactive sources. The existence of radioisotopes, however, was observed by measurements of the gamma-rays with a HPGe detector. In this study, in order to clarify the contents of trace elements, the hormesis cosmetics including radioactive sources were analyzed using INAA, PGAA and NAA with multiple gamma-ray detection (NAAMG). Nineteen elements were analyzed quantitatively in hormesis cosmetics by INAA, PGAA and NAAMG and 16 elements were detected qualitatively by SEM-EPMA. (author)
2008-12-01
NMR study of one-dimensional ionic conductor with hollandite-type structure (IV) Rb-priderite
International Nuclear Information System (INIS)
Conduction properties of Rb"+ ion in Rb-Al-priderite and K"+ ion and Rb"+ ion in (K,Rb)-Al-priderite, were investigated by NMR using "2"7Al in the framework as a probe. Size effect was observed remarkably in the activation energies. Frequency dependence of T_1 in Rb-Al-priderite at a low temperature indicates that the relaxation behavior of "2"7Al in Rb-Al-priderite can be described by the continuum model. Barrier height distributions and 'attempt frequencies' in both samples obtained by a curve-fitting method are discussed in comparison with those of K-Al-priderite. (orig.).
1985-08-18
Daya Bay reactor anti-neutrino experiment
International Nuclear Information System (INIS)
The Daya Bay Reactor Anti-Neutrino Experiment is a neutrino oscillation experiment designed to observe and measure the neutrino mixing angle ?13. The sensitivity goal is 0.01 in sin 22?13 at the 90% confidence level, a significant improvement over the current limit. This will be accomplished by measuring the relative rates and energy spectra of reactor electron antineutrinos with multiple detectors positioned at different baselines. Civil construction is currently under-way as detector designs and planning near completion. Commissioning activities should be completed by the end of 2010, followed by a three-year run.
2008-11-01
The surface composition and composition near the surface and properties of high-silica zeolites of the TsVK-1 type were studied by XPES, IRS, and low-temperature adsorption of N/sub 2/. It was found that changing the sequence of operations during preparation of the H form of the zeolites results in a different set of acid centers on their surface, caused by migration of cations into the bulk of the zeolites. Migration of elements is also observed during the catalytic reaction of conversion of ethanol.
1988-08-01
Energy Technology Data Exchange (ETDEWEB)
Hydrogen and helium cosmic ray nuclei spectra gathered from 1976 to 1993 have been corrected to the top of the atmosphere and normalized at high rigidities. The variation of these primary cosmic ray fluxes above 400 MeV/nucleon has been examined as a function of the phase of the solar cycle with the force-field approximation model. The intensity of the normalized fluxes between solar maximum and minimum conditions varies by a factor of 6 for hydrogen and a factor of 4.3 for helium at the lowest rigidities considered.
1995-09-01
Solar cells in architecture; Solceller i arkitekturen
Energy Technology Data Exchange (ETDEWEB)
This book contains the results of an architectural evaluation of building examples with integrated photovoltaic. Danish Building and Urban Research and Danish Technological Institute conducted the work within the framework of Solar Energy Centre Denmark. Seven examples are selected to inspire Danish architects and building owners to use PV in the building environment. The examples come from Denmark and countries (the Netherlands and Germany) with similar building traditions, climate and solar conditions. All the examples demonstrate architectural concepts that integrate photovoltaic as a natural part of the building envelope. (BA)
2002-07-01
Review of the application of molecular beam epitaxy for high efficiency solar cell research
Energy Technology Data Exchange (ETDEWEB)
In the last two years, rapid progress has been made in the energy conversion efficiencies of GaAs solar cells fabricated from molecular beam epitaxy (MBE) material. The efficiencies of cells fabricated from MBE material are now comparable with those fabricated from metal-organic chemical vapor deposition material, even for cells of dimension 2 cmx4 cm. This paper reviews the progress in MBE cell efficiencies. Also discussed is the role oval defects play in GaAs diode and solar cell performance. (orig.).
1991-05-01
Partial inhibition of in vitro pollen germination by simulated solar ultraviolet-B radiation
Energy Technology Data Exchange (ETDEWEB)
Pollen from four temperate-latitude taxa were treated with UV radiation in a portion of the UV-B (280-320 nm) waveband during in vitro germination. Inhibition of germination was noted in this pollen compared to samples treated identically except for the exclusion of the UV-B portion of the spectrum. Levels similar to maximum solar UV-B found in temperate-latitude areas failed to inhibit pollen germination significantly, while levels similar to maximum solar UV-B found in equatorial alpine locations caused partial inhibition of germination in three of the four taxa examined.
1984-01-01
Mobile-mirror concentrators for solar thermal power plants
Energy Technology Data Exchange (ETDEWEB)
Seven central-receiver, solar-thermal power plants with heliostat concentrators have been built around the world in the last two decades. This technology has proven to be much too expensive for commercial power plants and efforts to reduce the cost have reached an impasse. It is the nature of the solar concentrators which makes it so expensive. There are two types of concentrators: those, called heliostats, with mirrors on stationary supports, and those with mirrors on mobile supports. Mobile mirrors are potentially much cheaper than heliostats.
1999-11-01
Method of forming solar cells by grid contact isolation
Energy Technology Data Exchange (ETDEWEB)
A solar cell structure is produced by a method comprising baking the solar cell, containing a gridded top layer of cuprous sulfide formed on a base of cadmium sulfide, for 20 minutes to 10 hours, to produce a copper doped cds electrically insulating region in the cadmium sulfide base near the interface of the cuprous sulfide and the cadmium sulfide; removing the cuprous sulfide, and the copper doped cds insulating region not covered by the grid, to provide a bare cadmium sulfide areas; and then forming a cuprous sulfide layer on the exposed areas not covered by the grid.
1982-03-16
Laser-assisted solar cell metallization processing
In this contract, Laser-assisted processing techniques for producing high-quality solar cell metallization patterns are being investigated, developed, and characterized. The tasks comprising these investigations are outlined. Four new batches of solar cells were processed, in addition to several test runs on wafers, using the laser decomposition of spun-on silver neodecanoate to metallize cells. Decomposition of silver neodecanoate was carried out at different laser powers on different cells on a given wafer to determine whether this would have any effect on cell performance. A one watt laser power gave an electroplated linewidth of 50 microns , while at 8 watts the line width was 90 microns.
1986-01-01
Hybrid solar/combustion powered receiver
Energy Technology Data Exchange (ETDEWEB)
An improved hybrid solar/combustion powered receiver of the type having an insulated housing with a front end and a rear end, a heat exchanger positioned adjacent the rear housing end for extracting heat energy out of the receiver, the insulated housing surrounding the heat exchanger and forming a receiver cavity, the housing also including an aperature having an aperture axis, the aperture located in the front housing end for admitting solar radiation to the cavity to impinge upon the heat exchanger, and a plurality of gas burners to provide combustion gases within the receiver.
1986-07-29
High efficiency GaInP/GaAs tandem solar cells
Energy Technology Data Exchange (ETDEWEB)
We report on multijunction GaInP/GaAs photovoltaic cells with total-area efficiencies of 29.5% at one-sun concentration and air mass (AM) 1.5 global and 25.7% one-sun, AM0. These values represent the highest efficiencies achieved by any solar cell under these illumination conditions. Three key areas in this technology are identified and discussed: the grid design, front surface passivation of the top cell, and bottom surface passivation of both cells. Aspects of cell design related to its operation under different solar spectra and under concentration are also discussed.
1994-06-30
Experimental studies on non-parabolic asymmetrical solar concentrators with evacuated receivers
Energy Technology Data Exchange (ETDEWEB)
Asymmetrical solar concentrators may offer significant advantages over symmetrical ones by the higher yearly average energy input per unit aperture area and the wider range of flexibilities in the design and operation. This paper describes the design, construction and performance evaluation of a non-parabolic asymmetrical solar concentrator with an evacuated receiver. The concentrator has a concentration ratio of 3.25 and a theoretical optical efficiency of 0.67. Collector efficiency test results are presented and compared with another similar concentrator without an evacuated receiver.
1983-06-01
Design criterion for tubed solar-heated cavity receivers
Energy Technology Data Exchange (ETDEWEB)
Solar energy can be economically converted into electrical energy for small and medium power outputs. A typical solar power plant consists of a parabolic dish, cavity receiver and gas turbine. To obtain high gas turbine efficiences, the working fluid used has to be heated to high temperatures. This necessitates the use of expensive high-quality materials for the tubes in the receiver. This expense must be kept to a minimum. The present paper demonstrates how this aim can be achieved by meeting the so-called Bammert Criterion.
1986-07-01
Design criterion for tubed solar-heated cavity receivers
Energy Technology Data Exchange (ETDEWEB)
Solar energy can be economically converted into electrical energy for small and medium power outputs. A typical solar power plant consists of a parabolic dish, cavity receiver and gas turbine. To obtain high gas turbine efficiencies, the working fluid used has to be heated to high temperatures. This necessitates the use of expensive high-quality materials for the tubes in the receiver. This expense must be kept to a minimum. The present paper demonstrates how this aim can be achieved by meeting the so-called Bammert Criterion.
1986-01-01
Analysis of the thermal performance of dynamic solar systems
Energy Technology Data Exchange (ETDEWEB)
This article proposes a model for estimating the effect of the overall thermal resistance of the absorber and the coolant on a solar thermal energy system utilizing advanced heat transfer mediums. Two equations can be used to model a dynamic system: one for the maximum conversion efficiency and one to specify the constraint that, in quasi-steady state, the net energy collected must be transferred to the coolant. These two equations define a constrained optimization problem in two variables, the fluid and the absorber temperatures. The results present interesting implications for liquid metal, direct absorption, and solar evaporating systems.
1996-03-01
A mathematical model for simulating shallow solar ponds for treatment of industrial wastewater
Energy Technology Data Exchange (ETDEWEB)
This paper presents a mathematical model to analyze the solar evaporation in a shallow pond in steady state, when the inlet flow rate, concentration, surface area and solar radiation are given. The simultaneous heat and mass transfer mechanisms are considered for quantifying the amount of evaporated water to the atmosphere and the actual absorbed heat by wastewater is calculated to obtain the bottom temperature of water pond. The heat losses to air by radiation and convection mechanisms are considered and the heat transmission across the water film is evaluated by the forced convection mechanism. 6 refs., 5 figs., 1 tab.
1996-12-31
Biological Surface-Active Substance
International Science & Technology Center (ISTC)
Development of biological preparation with surfactant activity
Locally Optimally-emitting Clouds and the Narrow Emission Lines in Seyfert Galaxies
The narrow emission line spectra of active galactic nuclei are not accurately described by simple photoionization models of single clouds. Recent Hubble Space Telescope images of Seyfert 2 galaxies show that these objects are rich with ionization cones, knots, filaments, and strands of ionized gas. Here we extend to the narrow line region the ``locally optimally emitting cloud'' (LOC) model, in which the observed spectra are predominantly determined by powerful selection effects. We present a large grid of photoionization models covering a wide range of physical conditions and show the optimal conditions for producing many of the strongest emission lines. We show that the integrated narrow line spectrum can be predicted by an integration of an ensemble of clouds, and we present these results in the form of diagnostic line ratio diagrams making comparisons with observations. We also predict key diagnostic line ratios as a ...
1997-01-01
Implications of the dwarfs spheroidal galaxy mass-metallicity relation
International Nuclear Information System (INIS)
The properties of the mass-metallicity relation among dwarf spheroidal galaxies are discussed in terms of a model which assumes that the internal chemical evolution of the dwarf spheroidals was promoted by supernova activity. The model can be used to explain the observed dwarf spheroidal mass-metallicity relation assuming the present mass of these systems M sub s is proportional to their initial masses M as M sub s varies according to a power-law index of exp 7/4. It is inferred from the power-law dependence of M on the proto-cloud radius that the most massive dwarf spheroids were formed from the densest clouds. The observed slope of the mass-metallicity relation for dwarf spheroidal galaxies is found to be significantly different from theoretical estimates of this slope for elliptical galaxies. It is suggested that the difference may imply that spheroidal dwarfs and elliptical galaxies had different formation histories, ...
Exploring Quantum Gravity with Very-High-Energy Gamma-Ray Instruments - Prospects and Limitations
Some models for quantum gravity (QG) violate Lorentz invariance and predict an energy dependence of the speed of light, leading to a dispersion of high-energy gamma-ray signals that travel over cosmological distances. Limits on the dispersion from short-duration substructures observed in gamma-rays emitted by gamma-ray bursts (GRBs) at cosmological distances have provided interesting bounds on Lorentz invariance violation (LIV). Recent observations of unprecedentedly fast flares in the very-high energy gamma-ray emission of the active galactic nuclei (AGNs) Mkn 501 in 2005 and PKS 2155-304 in 2006 resulted in the most constraining limits on LIV from light-travel observations, approaching the Planck mass scale, at which QG effects are assumed to become important. I review the current status of LIV searches using GRBs and AGN flare events, and discuss limitations of light-travel time analyses and ...
2009-01-01
Excess of seminomas observed in Vietnam service U.S. military workingn> dogs.
During the Vietnam War, US military working dogs served with their companion dog handlers in close proximity, sharing common exposures to war-related activity, many zoonotic infectious agents, chemical pesticides, phenoxy herbicides, and extensive use of therapeutic drugs. To gain insight into the effects of the Vietnam experience, we investigated the occurrence of neoplasms in military working dogs based on standard necropsy examination by the Armed Forces Institute of Pathology. We observed that these dogs experienced significant elevated risks for testicular seminoma and, independently, testicular dysfunction. Experimental evidence shows testicular dysfunction and impaired spermatogenesis in laboratory animals exposed to phenoxy herbicides, dioxin, or tetracycline, and antibiotic used extensively in military working dogs in Vietnam. Because an unexplained significant decrease in sperm quality in Vietnam veterans has been ...
1990-06-20
We report the results of mapping observations of the bipolar nebula with SiO maser emission, IRAS 19312+1950, in the CO (J=1-0 and J=2-1), 13CO (J=1-0 and J=2-1), C18O (J=1-0), CS (J=2-1), SO (J_K=3_2-2_1) and HCO+ (J=3-2) lines with the Berkeley-Illinois-Maryland Association array. Evolutional status of this source has been evoking a controversy since its discovery, though SiO maser sources are usually identified as late-type stars with active mass loss. In line profiles, two kinematical components are found as reported in previous single-dish observations: a broad pedestal component and a narrow component. Spatio-kinetic properties of a broad component region traced by 12CO lines are roughly explained by a simple spherical outflow model with a typical expanding velocity of an AGB star, though some properties of the broad component region still conflict with properties of a typical AGB spherical outflow. A narrow component ...
2005-01-01
An alternative explanation of the COBE data
Energy Technology Data Exchange (ETDEWEB)
The COBE data on cosmic background radiation (CBR) isotropy and spectrum are generally considered to be explicable only in the context of the Big Bang theory and to be confirmation of that theory. However, this data can also be explained by an alternative, non-Big Bang model which hypothesizes an intergalactic radio-absorbing and scattering medium. Dense, force-free magnetic filaments generated by quasars, active galactic nuclei and Herbig-Haro objects can remain stable in the intergalactic medium for many Gy. They will be opaque to radiation with wavelengths longer than 100--400 microns, and essentially transparent to shorter wavelengths. They are thus capable of thermalizing and isotropizing the cosmic background radiation, and of accounting for the observed decrease of radio luminosity of galaxies within increasing distance from earth. A simple, inhomogeneous model of such an absorbing medium can reproduce both the isotropy and spectrum of ...
1994-12-31
Energy Technology Data Exchange (ETDEWEB)
The possibility of improving the cold formability of wrought magnesium alloys is considered in light of their good hot forming characteristics. Magnesium alloy AZ31B sheet is selected as a model system. Parameters affecting formability, such as strain hardening rate, strain rate sensitivity, and the degree of anisotropy are examined systematically by conducting tensile tests over a range of temperatures (room temperature to 250 C) and strain rates (1 x 10{sup -5} to 0.1 s{sup -1}). The plastic anisotropy and deformation texture evolution are examined in samples aligned with the sheet rolling and transverse directions. Polycrystal plasticity simulations using a viscoplastic self-consistent (VPSC) formulation are used to model the observed anisotropy and texture evolution. The adjustable parameters in the model are the relative critical resolved shear stresses of the dislocation mechanisms known to operate within magnesium. The experimental results suggest that an ...
2003-07-01
VIS harvesting unsymmetrical squaraine dye for dye-sensitized solar cells
British Library Electronic Table of Contents (United Kingdom)
An unsymmetrical squaraine dye which contains an arylamino group was synthesized and used in dye-sensitized solar cells. The molar extinction coefficient of the dye is 77793 M-1 cm-1. Because our synthesized molecule may have no diradical character or the contribution of the diradicaloid component to resonance is quite small, the newly designed squaraine dye has a maximum absorption at 546 nm in the visible region compared with the NIR squaraine sensitizers. Cyclic voltammetry and time dependent density function theory calculation were accomplished to scrutinize the sensitized performance of the dye. Meanwhile, the novel sensitizer has been used to sensitize nanocrystalline TiO2-based solar cell. Under standard global AM 1.5 solar conditions, the squaraine dye-sensitized cell gives a short...
2012-01-01
British Library Electronic Table of Contents (United Kingdom)
This paper presents a two-stage solar multi-effect humidification dehumidification desalination process plotted from pinch analysis. The sketch of two-stage solar multi-effect humidification dehumidification desalination process is given. The solar vacuated tube collector is employed in the desalination system, multi-effect humidification dehumidification desalination (HDD) process are plotted two different temperature range according to pinch technology. The higher temperature range is from 60 to 80?C, and the lower is from 30 to 60?C. The mass flow rates of dry air in the two stage desalination units are different. The pinch analysis chart is given. According to the pinch chart, the energy recover rate could get higher according to working temperature range. The research proves that the ...
2008-01-01
System performance of a solar thermophotovoltaic system for space and terrestrial application
Energy Technology Data Exchange (ETDEWEB)
Solar thermophotovoltaics (STPV) potentially have high system power efficiency together with other attractive attributes for both space and terrestrial applications. This paper presents a summary of work that has been conducted by NASA Lewis Research Center (LeRC) and McDonnell Douglas Aerospace (MDA). The paper discusses analytical modeling and subsystem testing, laboratory, and field testing that has been conducted. The features which make solar thermophotovoltaics attractive for both space and terrestrial applications are discussed. Based upon these investigations and the work of others, a conceptual design has been formulated, and an estimate of system performance is presented. This estimate indicates a solar thermophotovoltaics system can result in competitive energy costs for the utility electrical market applications and a high power-to-mass ratio for space power applications.
1995-12-31
Space Science - NASA Headquarters
Canada will provide telescope baffles and fine error sensor assemblies. ..... ( Ongoing) Flight tests aboard sounding rockets and balloon planned for FY 1995. .... the effects of incoming energetic particles and solar radiation on the ...
Solar distillation as an appropriate technology tool in Haiti
Energy Technology Data Exchange (ETDEWEB)
Source Philippe (on the island of La Govave, near Haiti) is described in terms of climatic, sociological, agricultural and technical background. Because of drought conditions, it became necessary to develop a solar still to provide the town with sufficient fresh water. The still, which has been in operation since 1969, is described in some detail as is the construction process. Brackish and sea water are used to produce more than 1250 liters of fresh water each day. A windmill is used to pump the brackish water from a well to an elevated storage tank; it flows by gravity to solar still basins where it is vaporized, then condensed on a sloping glass surface and collected. Benefits of the solar still to the town's economy and health are discussed. Cost of the project was $17,000. 10 references. (MJJ)
1980-06-01
Renewable energy technology for off-grid power generation solar hybrid system
International Nuclear Information System (INIS)
Off-grid power generation is meant to supply remote or rural area, where grid connection is almost impossible in terms of cost and geography, such as island, aborigine's villages, and areas where nature preservation is concern. Harnessing an abundance renewable energy sources using versatile hybrid power systems can offer the best, least-cost alternative solution for extending modern energy services to remote and isolated communities. The conventional method for off-grid power generation is using diesel generator with a renewable energy (RE) technology utilizing solar photovoltaic, wind, biomass, biogas and/or mini/micro hydro. A hybrid technology is a combination of multiple source of energy; such as RE and diesel generator and may also include energy storage such as battery. In our design, the concept of solar hybrid system is a combination of solar with diesel genset and battery as an energy storage. The main objective ...
2006-12-01
Remote Sensing Tutorial ... - The Remote Sensing Tutorial - NASA
The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...
Power efficiency for very high temperature solar thermal cavity receivers
This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the absorber. With this arrangement, a high percentage of the ...
1984-01-01
Power efficiency for very high temperature solar thermal cavity receivers
Energy Technology Data Exchange (ETDEWEB)
This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the absorber. With this arrangement, a high percentage of the ...
1984-10-30
NOTICE THIS DOCUMENT HAS BEEN REPRODUCED FROM - NASA Technical ...
COATINGS FOR THE METAL-SEMICONDUCTOR SOLAR CELLS 3S GIVEN. THIS METHOD UTILIZES THE MEASURED EQUIVALENT INDEX OF. REFRACTION OBTAINED FROM ELLIPSOMETRY ...
NASA Orbiter Finds Possible Cave Skylights on Mars - Solar System ...
Sep 21, 2007... at night," said Glen Cushing of the U.S. Geological Survey's Astrogeology Team and of Northern Arizona University, Flagstaff, Ariz. ...
NASA Blueshift - Astrophysics Science Division - NASA
We here at Blueshift do our best to cover all things astrophysics, which we rather loosely define as 'anything and everything outside the Solar System. ...
Measured Temperatures of Solid Rocket Motors Dump Stored ...
... TARGET SENSOR-MK 80 SERIES BOMBS ... 5-inch-, and 2.75-inch- diameter rocket motors that ... balance when compared to incoming solar radiation ...
1989-07-01
Previous experimental data and theoretical analysis have demonstrated that ... products of a technological process) but also other contaminants. ..... Thorough outgassing of solar array surfaces may result in significant decrease of arc ...
Long-term storage of solar heat
Energy Technology Data Exchange (ETDEWEB)
Stochastic models for the simulation of global radiation are discussed. Thermal transients in the ground are analyzed. The performance of buried-pipe storage and a space heating system with long-term storage is described.
1981-06-01
Jupiter Solar Mission Alternative Feasibility Study
Because of its direct energy conversion techniques, AMTEC is the front runner today. However, because these systems are now only in the preliminary design ...
Improved power efficiency for very-high-temperature solar-thermal-cavity receivers
Energy Technology Data Exchange (ETDEWEB)
This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positiond in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts radiation from the front of the absorber. With this arrangement, a high percentage of the ...
1982-04-14
Energy Technology Data Exchange (ETDEWEB)
Cavity type receivers are used extensively in concentrating solar thermal energy collecting systems. The Solar Total Energy Project (STEP) in Shenandoah, Georgia is a large scale field test for the collection of solar thermal energy. The STEP experiment consists of a large field array of solar collectors used to supplement the process steam, cooling and other electrical power requirements of an adjacent knitwear manufacturing facility. The purpose of the tests, conducted for this study, was to isolate and quantify the radiative, conductive, and convective components of total heat loss, and to determine the effects of operating temperature, receiver angle, and aperture size on cavity heat loss. An analytical model for radiative heat loss was developed and compared with two other methods used to determine radiative heat loss. A proposed convective heat loss correlation, including effects of aperture size, ...
1995-12-01
Genesis : Search for Origins | JPL | NASA
(telescopes, cameras, mirrors, solar cookers); Explain to students that the Genesis spacecraft has a concentrator that collects special types of atoms from ...
General Disclaimer One or more of the Following Statements may ...
LASERASSISTED SOLAR CELL METALLIZATION PROCESSING DOE/JPL/956615--84/3. S. Dutta and P. G. McMullin. Quarterly Report for the period March 13 ...
EUROPEAN SPACE AGENCY Extension of the SOHO Mission
closure of the BISON network, GOLF and VIRGO will remain the only instruments ...... Faraday Cup solar wind instrument as described in Ipavich et al (1998). ...
Direct solar thermal-to-electric energy conversion using thermophotovoltaics
Energy Technology Data Exchange (ETDEWEB)
Thermophotovoltaic energy conversion achieves direct conversion of thermal energy to electricity without the need for complex dynamic machinery operating in one of several possible thermodynamic cycles. This paper presents an analysis of a hybrid solar thermophotovoltaic (STPV) energy conversion system in which a receiver/photovoltaic (PV) array subsystem is powered by either a solar concentrator or a fossil fuel combustion source. The overall TPV system efficiency is calculated using an appropriate selective emitter and a spectrally tuned solar cell designed to achieve maximum conversion efficiency in the narrow band emitted by the selective emitter. Two limiting cases are examined to place upper and lower bounds on system performance. The estimates of system performance are based on actual experimental data from PV cells and selective emitters.
1995-10-01
Development of a solar thermal storage system suitable for the farmhouse heating in northeast China
Energy Technology Data Exchange (ETDEWEB)
This study reported on the performance of a passive solar radiant floor heating system designed for standard energy-saving farmhouses in northeast China. Weather data in the region was analyzed in terms of solar radiation, temperature, humidity and light levels. The heating characteristics of the building materials such as windows, doors, walls and roofs were also analyzed along with the indoor thermal environment of the farmhouse. The heating load was then calculated along with the size of the thermal storage element and the area of the collector element. The passive solar radiant floor heating system was designed for heating during the winter and cooling in summer. According to the results, the heating characteristics of the system have the potential to improve farming villages environment and the use of renewable energy.
2010-07-01
Development of a greenhouse-type solar dryer for medicinal plants and herbs
Energy Technology Data Exchange (ETDEWEB)
The economy of medicinal plant production is burdened considerably by the energy costs of drying. To substitute fossil energy, a solar heated dryer was developed, taking a plastic film greenhouse as superstructure to lower the initial costs. The solar air heaters, being incorporated into the roof, consist of a black absorber tissue, which is placed between the transparent cover of the greenhouse and an insulating air-bubble foil. To obtain a modular design, the system is structured along the ridge into segments of 2 m width. Each segment forms an independent solar air heater/batch dryer unit and is operated by a fan with a power consumption of 500 W. A prototype was tested in Yugoslavia, drying mint, sage and hops. (author).
1989-01-01
International Nuclear Information System (INIS)
1971. Australia Dorman, LI Yakhno, OI AN SSSR, Moscow. Inst. Zemnogo
1971-08-16
DOE Solar Decathlon: News Blog
shading trellis. This array powers all of the electric appliances, including an oven, cooktop, dishwasher, clothes washer and dryer, home entertainment systems (television and...
2011-09-04
Convective losses from solar central receivers: proceedings of a DOE/SERI/SNLL workshop
Energy Technology Data Exchange (ETDEWEB)
Separate abstracts were prepared for 13 papers in these proceedings. Also included is an overview speech and a panel discussion. (LEW)
1981-10-01
Contamination Effects of Satellite Material Outgassing ...
... A detailed analysis of QCM errors is ... Surface Effects of Satellite Outgassing Products." AIAA Journal ... 9. Rauschenbach, H. S. Solar Cell Array Design ...
1990-12-01
Comparative study in supplying electrical energy to small remote loads in Libya
Energy Technology Data Exchange (ETDEWEB)
The main sources of energy that might be available in remote low populated areas of Libya are either diesel generating units or wind mills for water pumping. Several problems in the working performance of these two types of energy production may arise due to environmental conditions. Direct conversion of solar energy can replace other ways of energy delivery or production, especially in this country where the solar radiation all year is relatively high. Direct conversion of solar energy is relatively expensive, however the cost of erecting long feeders and supervising them may be much more expensive than the usage of solar systems. This paper investigates the economics associated with either solutions of energy production. A case study is given in detail to supply one of the remote areas with a population of about 250. (author)
1998-05-01
Bawolek - Solar System Exploration - NASA
She completed Northern Arizona University's post-baccalaureate program, and received her M.E.d from Arizona State University with a focus in cognitive ...
An exergy based test protocol for truncated pyramid type solar box cooker
British Library Electronic Table of Contents (United Kingdom)
Developing a test standard/protocol for solar box type cookers has drawn a considerable interest among the researchers throughout the world. Recent publications on solar cookers emphasize the need of introducing the thermal performance indicators determined through exergy analysis. In the present paper, the time variation of instantaneous exergy output and energy output as function of its temperature and also of the instantaneous ambient temperature have been reported for truncated pyramid type solar box cooker and compared with those of box type cooker. Further, variations in the exergy lost with temperature difference have been depicted for the selected water temperature range from 60 degreeC to 95 degreeC. Based on this study, quality factor, exergy temperature difference gap product, a...
2011-01-01
Vestibular dysfunction was chemically induced in male meadow voles (Microtus pennsylvanicus) by intratympanic injections (30 mg per side) of sodium arsanilate (atoxyl). The control group received intratympanic injections of isotonic saline. After a one-week recovery period the voles were behaviorally assayed for integrity of their labyrinthine systems. All subjects were tested for the presence of the air-righting reflex and body rotation-induced nystagmus. Three weeks later a multivariate assessment of spontaneous motor activity of the voles was carried out in the automated Digiscan Activity Monitor. In addition, the swimming behavior of the voles was examined. Voles with vestibular dysfunction exhibited pronounced postural abnormalities (head dorsiflexion), were not able to swim with their nose above the water for a 1 min test period, and displayed disorientation and thrashing movements. In the Digiscan activity test the ...
1992-03-15
International Nuclear Information System (INIS)
A selected series of 24 patients with displaced medial femoral neck fracture, treated with closed reduction and osteosynthesis with cancellous bone screws (ASIF), were investigated. During an observation period of 6 to 26 months, serial hip joint scintigraphies were performed and compared with serial X-ray examinations. At the first scintigraphic examination performed on average 5-6 weeks after the fracture, two separate investigators found a decreased amount of activity or no activity in the femoral head of 10 and 8 patients, respectively. At the second scintigraphic examination performed on average 11.1 weeks after the fracture both investigators found no activity or a decreased amount of activity in 8 patients. This figure declined to 7 during the following period, because one patient with decreased activity was recorded as having normal ...
Catalysis on Mo(CO)/sub 6/-derived supported molybdenum catalysts: CO oxidation with N/sub 2/O
Energy Technology Data Exchange (ETDEWEB)
The catalytic nature of Mo(CO)/sub 6/ supported on ..gamma..-Al/sub 2/O/sub 3/, KOH-doped ..gamma..-Al/sub 2/O/sub 3/, and HY-zeolite was investigated in CO oxidation with N/sub 2/O in comparison with that of a conventional partially reduced MoO/sub 3//..gamma..-Al/sub 2/O/sub 3/ catalyst. Kinetic parameters of this reaction were obtained in the range 0 to 100/sup 0/C; the rate law r = kP/sub N/sub 2/O//sup 1/P/sub CO//sup 0/ was found on all catalysts, and the activation energy was estimated to be 9.1 kcal/mol on the Mo(CO)/sub 6/-derived catalysts and 7.1 kcal/mol on the partially reduced MoO/sub 3//..gamma..-Al/sub 2/O/sub 3/ catalyst. Maximum catalytic activities were obtained by activating the Mo(CO)/sub 6/-derived catalysts at 400/sup 0/C. To obtain similar activity on the MoO/sub 3//..gamma..-Al/sub 2/O/sub 3/ catalyst, it was necessary to reduce at 600/sup 0/C. The former catalysts were ...
1988-05-01
A simple template-free approach to TiO2 hollow spheres with enhanced photocatalytic activity.
Mesporous anatase-phase TiO(2) hollow spheres with high photocatalytic activity were prepared by hydrothermal treatment and self-transformation of amorphous TiO(2) solid spheres in an NH(4)F aqueous solution. The prepared samples were characterized by X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, N(2) adsorption-desorption isotherms and UV-vis absorption spectroscopy. The photocatalytic activity was evaluated by photocatalytic oxidation decomposition of acetone in air under UV irradiation. It is found that F(-) plays an essential role in the formation of TiO(2) hollow spheres. F(-) not only induces the hollowing of TiO(2) solid spheres, but also promotes the crystallization of anatase TiO(2) nanocrystals. A possible formation mechanism for the TiO(2) hollow spheres by localized Ostwald ripening or chemically induced self-transformation is proposed based on the experimental ...
2010-05-27
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