20,184 research outputs found
Wide-range dynamic pressure sensor
Transducer measures pressure by sensing the damping of a vibrating diaphragm immersed in the atmosphere to be measured. Improved sensor can be included in rugged, lightweight package for use aboard aircraft, meteorological vehicles, and space probes
Electronic structure and magnetism in two-dimensional hexagonal 5d transition metal carbides, Tan+1Cn (n=1,2,3)
Density functional calculations are used to investigate the electronic
structure of two-dimensional 5d tantalum carbides with honeycomb-like lattice
structures. We focus on changes in the low-energy bands near the Fermi level
with dimensionality. We find that the Ta 5d states dominate, but the extended
nature of the wavefunctions makes them weakly correlated. The carbide sheets
are prone to long range magnetic order. We evaluate the stability of these
states to enhanced electron--electron interactions through a Hubbard U
correction. Lastly, we find spin orbit interactions strongly renormalize the
band structure for n=2, but play a minor role in n=1 and 3.Comment: 4 pages, 4 figure
Space Station Spartan study
The required extension, enhancement, and upgrading of the present Spartan concept are described to conduct operations from the space station using the station's unique facilities and operational features. The space station Spartan (3S), the free flyer will be deployed from and returned to the space station and will conduct scientific missions of much longer duration than possible with the current Spartan. The potential benefits of a space station Spartan are enumerated. The objectives of the study are: (1) to develop a credible concept for a space station Spartan; and (2) to determine the associated requirements and interfaces with the space station to help ensure that the 3S can be properly accommodated
ECON 6250
The purpose of this course is to give students an overview of the major economic considerations in the health care industry and to demonstrate how economic ideas are crucial to an understanding of the functioning of the health care system from both policy (external) and health care management (internal) points of view. There will be a strong emphasis both on economic theory and on empirical studies of the various topics
ECON 4250
The purpose of this course is to give students an overview of the major economic considerations in the health care industry and to demonstrate how economic ideas are crucial to an understanding of the functioning of the health care system from both policy (external) and health care management (internal) points of view. There will be a strong emphasis both on economic theory and on empirical studies of the various topics
ECON 6250
The purpose of this course is to give students an overview of the major economic considerations in the health care industry and to demonstrate how economic ideas are crucial to an understanding of the functioning of the health care system from both policy (external) and health care management (internal) points of view. There will be a strong emphasis both on economic theory and on empirical studies of the various topics
Use of combinatorial analysis for the study of new material for solar cells applications
This paper presents a combinatorial method for the deposition and
characterization of new metallic precursors for photovoltaic materials.
Onedimensional thin film alloy “libraries” were electrodeposited on Mo-coated
glass. The library elements were deposited in two consecutive baths and then
heated in a reducing atmosphere to promote interdiffusion of the elements. At
the end of this process, the libraries possessed a composition gradient along
their lengths, with single elements at their two opposite ends and one or more
alloys and/or a solid state solution in between. This continuous range of
compositions can therefore be considered a collection of specific precursors
that can be interrogated by examining their corresponding locations, with the
crystallographic structure along the library changing in accordance with the
phase diagram for the metals. The libraries were then sulphurised or selenised
by heating in a sulphur-rich or selenium rich atmosphere; this converted the
metallic precursors in a continuous range of materials, candidates for potential
solar cells absorbers. The libraries were analysed by X-ray diffraction and
energy dispersive X-ray spectrometry. The X-ray diffraction results show phase
changes across the libraries, which can be correlated with the original
precursor concentration at that particular p
Observations of the Io plasma torus
The short wavelength spectrography on the IUE satellite was used to obtain spectra of the plasma torus near the orbit of Io about Jupiter. Three exposures of about 8 hours each taken in March and May 1979 show emission features due to SII, SIII, and OIII. The absence of features at other wavelengths permits upper limits to be other species in the torus
Observations of polar aurora on Jupiter
North-south spatial maps of Jupiter were obtained with the SWP camera in IUE observations of 10 December 1978, 19 May 1979, and 7 June 1979. Bright auroral emissions were detected from the north and south polar regions at H Ly alpha (1216 A) and in the H2 Lyman bands (1250-1608 A) on 19 May 1979; yet no enhanced polar emission was detected on the other days. The relationship between the IUE observing geometry and the geometry of the Jovian magnetosphere is discussed
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