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This paper is an interim report of our inferences about the hydrostatic structure of the Sun, following the first report of the GONG team in Science (Gough et al., 1996). That work confirms that the spherically averaged structure of the Sun is more or less in agreement with current standard solar models. However, there remain some significant deviations which we regard as important clues to the existence of dynamical phenomena which are not taken into account in standard solar modelling.
Mid-infrared (MIR) quasar spectra exhibit a suite of emission features including high ionization coronal lines from the narrow line region (NLR) illuminated by the ionizing continuum, and hot dust features from grains, as well as polycyclic aromatic hydrocarbons (PAH) features from star formation in the host galaxy. Few features are detected in most spectra because of typically low signal-to-noise ratio (S/N) data. By generating spectral composites in three different luminosity bins from over 180 Spitzer Ifnfrared Spectrograph (IRS) observations, we boost the S/N and reveal important features in the complex spectra. We detect high-ionization, forbidden emission lines in all templates, PAH features in all but the most luminous objects, and broad silicate and graphite features in emission whose strength increases relative to the continuum with luminosity. We find that the intrinsic quasar spectrum for all luminosity templates is consistent, and the differences in the spectra can be explained by host galaxy contamination in the lower luminosity templates. We also posit that star formation may be active in most quasar host galaxies, but the spectral features of star formation are only detectable if the quasar is faint.
Pulsed d.c Magnetron Sputtering (PdcMS) has been investigated for the first time to study the deposition of copper indium gallium diselenide (CIGS) thin films for photovoltaic applications. Pulsing the d.c. in the mid frequency region enhances the ion intensity and enables long term arc-free operation for the deposition of high resistivity materials such as CIGS. It has the potential to produce films with good crystallinity, even at low substrate temperatures. However, the technique has not generally been applied to the absorber layers for photovoltaic applications. The growth of stoichiometric p-type CIGS with the desired electro-optical properties has always been a challenge, particularly over large areas, and has involved multiple steps often including a dangerous selenization process to compensate for selenium vacancies. The films deposited by PdcMS had a nearly ideal composition (Cu0.75In0.88Ga0.12Se2) as deposited at substrate temperatures ranging from no intentional heating to 400 °C. The films were found to be very dense and pin-hole free. The stoichiometry was independent of heating during the deposition, but the grain size increased with substrate temperature, reaching about ∼ 150 nm at 400 °C. Hot probe analysis showed that the layers were p-type. The physical, structural and optical properties of these films were analyzed using SEM, EDX, XRD, and UV-VIS-NIR spectroscopy. The material characteristics suggest that these films can be used for solar cell applications. This novel ion enhanced single step low temperature deposition technique may have a critical role in flexible and tandem solar cell applications compared to other conventional techniques which require higher temperatures.
Faecal moisture content can determine whether faeces appear soft or firm, and faecal character can influence whether owners are satisfied with a dog food. In a previous study, dogs appeared to produce softer faeces after noon. The purpose of the present study was to determine whether time of defecation affected canine faecal water content. A total of eight hound dogs were fed one of four canned diets as a single meal each morning for 1 week per diet in a Latin square design. All four diets contained approximately 77 % moisture and, on a DM basis, 24 MJ/kg gross energy, 23 % crude protein, 32 % crude fat, 31 % N-free extract and 1 % crude fibre. The proportion of dietary protein from soya-derived texturised vegetable protein (TVP):beef was 0:100, 14:86, 29:71 and 57:43, respectively. Soya carbohydrate partially replaced maize starch as TVP increased. Faeces were collected by direct catch during the sixth morning and afternoon of each diet period. Mean faecal moisture content was greater in the afternoon than in the morning (79 v. 71 %; P = 0·01) and increased with dietary TVP (P ≤ 0·0001), and there was an interaction between time of day and percentage TVP (P = 0·003). Faecal moisture content differed from morning to afternoon only with TVP in the diet. Faecal wet weight was similar from morning to afternoon. This suggests that time of day and presence of TVP from soya should be taken into account when evaluating the effect of a diet on faecal form and moisture content in dogs fed once daily.
Computer graphics systems that provide interactive display and manipulation of three-dimensional data are powerful tools for the analysis and communication of technical information required for characterization and design of a geologic repository for nuclear waste. Greater understanding of site performance and repository design information is possible when performance-assessment modeling results can be visually analyzed in relation to site geologic and hydrologic information and engineering data for surface and subsurface facilities. In turn, this enhanced visualization capability provides better communication between technical staff and program management with respect to analysis of available information and prioritization of program planning.
A commercially-available computer system was used to demonstrate some of the current technology for three-dimensional visualization within the architecture of information systems for nuclear waste management. This computer system was used to interactively visualize and analyze the information for two examples: 1) site-characterization and engineering data for a potential geologic repository at Yucca Mountain, Nevada; and 2) three-dimensional simulations of a hypothetical release and transport of contaminants from a source of radionuclides to the vadose zone. Users may assess the three-dimensional distribution of data and modeling results by interactive zooming, rotating, slicing, and peeling operations. For those parts of the database where information is sparse or not available, the software incorporates models for the interpolation and extrapolation of data over the three-dimensional space of interest.
A series of metals was examined for suitability for the Wheel Abrasion Experiment, one of ten microrover experiments of the Mars Pathfinder Mission. The seven candidate metals were: Ag, Al, Au, Cu, Ni, Pt, and W. Thin films of candidate metals from 0.1 to 1.0 micrometer thick were deposited on black anodized aluminum coupons by e-beam and resistive evaporation and chemical vapor deposition. Optical, corrosion, abrasion, and adhesion criteria were used to select Al, Ni, and Pt. A description is given of the deposition and testing of thin films, followed by a presentation of experimental data and a brief discussion of follow-on testing and flight qualification.
The Magnetism in Massive Stars (MiMeS) Project is a consensus collaboration among many of the foremost international researchers of the physics of hot, massive stars, with the basic aim of understanding the origin, evolution and impact of magnetic fields in these objects. At the time of writing, MiMeS Large Programs have acquired over 950 high-resolution polarised spectra of about 150 individual stars with spectral types from B5-O4, discovering new magnetic fields in a dozen hot, massive stars. The quality of this spectral and magnetic matériel is very high, and the Collaboration is keen to connect with colleagues capable of exploiting the data in new or unforeseen ways. In this paper we review the structure of the MiMeS observing programs and report the status of observations, data modeling and development of related theory.
Division X provides a common theme for astronomers using radio techniques to study a vast range of phenomena in the Universe, from exploring the Earth's ionosphere or making radar measurements in the Solar System, via mapping the distribution of gas and molecules in our own Galaxy and in other galaxies, to study the vast explosive processes in radio galaxies and QSOs and the faint afterglow of the Big Bang itself.