12,477 research outputs found
Structures in granitic bathyliths and associated foldbelts in relation to mineral resources
There are no author-identified significant results in this report
Electron paramagnetic resonance studies of slowly tumbling vanadyl spin probes in nematic liquid crystals
An analysis of EPR line shapes by the method of Polnaszek, Bruno, and Freed is made for slowly tumbling vanadyl spin probes in viscous nematic liquid crystals. The use of typical vanadyl complexes as spin probes for nematic liquid crystals is shown to simplify the theoretical analysis and the subsequent interpretation. Rotational correlation times tau and orientational ordering parameters S sub Z where slow tumbling effects are expected to be observed in vanadyl EPR spectra are indicated in a plot. Analysis of the inertial effects on the probe reorientation, which are induced by slowly fluctuating torque components of the local solvent structure, yield quantitative values for tau and S sub Z. The weakly ordered probe VOAA is in the slow tumbling region and displays these inertial effects throughout the nematic range of BEPC and Phase V. VOAA exhibits different reorientation behavior near the isotropic-nematic transition temperature than that displayed far below this transition temperature
Development and evaluation of an intervention to improve further education students' understanding of higher education assessment criteria: three studies
Three studies about helping Further Education students prepare for study at universityThis paper reports three studies about preparing Further Education (FE) students for the transition to Higher Education (HE) by improving their understanding of HE assessment criteria. In study 1, students and tutors in both FE and HE were interviewed for a qualitative analysis of their understandings and expectations about assessment criteria. In study 2, students in FE and HE completed questionnaires measuring self-rated understanding and ability about assessment criteria, and beliefs about essay writing. Studies 1 and 2 both showed that FE students were more confident than HE students about their understanding and ability in relation to assessment criteria, but FE studentsâ understandings suggested more surface approaches to learning and more naĂŻve epistemological beliefs. In study 3, a workshop intervention to improve FE studentsâ understandings of HE assessment criteria was evaluated in a comparative longitudinal trial. The intervention reduced FE studentsâ self-rated understanding and ability, and promoted more sophisticated beliefs about essay writing, by comparison with students who received standard tuition. We concluded that interventions to develop more realistic understandings of what is required in academic writing could be used to prepare FE students more effectively for the transition to HE
Triple-Pomeron Matrix Model for Dispersive Corrections to Nucleon-Nucleus Total Cross Section
Dispersive corrections to the total cross section for high-energy scattering
from a heavy nucleus are calculated using a matrix model, based on the
triple-Pomeron behavior of diffractive scattering from a single nucleon, for
the cross section operator connecting different states of the projectile
nucleon . Energy-dependent effects due to the decrease in longitudinal momentum
transfers and the opening of more channels with increasing energy are included.
The three leading terms in an expansion in the number of inelastic transitions
are evaluated and compared to exact results for the model in the uniform
nuclear density approximation for the the scattering of nucleons from Pb^{208}
for laboratory momenta ranging from 50 to 200 GeV/c.Comment: 16 pages, 2 figures, RevTex
The phase-dependent Infrared brightness of the extrasolar planet upsilon Andromedae b
The star upsilon Andromeda is orbited by three known planets, the innermost
of which has an orbital period of 4.617 days and a mass at least 0.69 that of
Jupiter. This planet is close enough to its host star that the radiation it
absorbs overwhelms its internal heat losses. Here we present the 24 micron
light curve of this system, obtained with the Spitzer Space Telescope. It shows
a clear variation in phase with the orbital motion of the innermost planet.
This is the first demonstration that such planets possess distinct hot
substellar (day) and cold antistellar (night) faces.Comment: "Director's cut" of paper to appear in Science, 27 October, 200
Genesis Mission Bulk Metallic Glass Solar Wind Collector: Characterization of Return Samples Available for Re-Allocation
The Genesis mission collected solar wind atoms for 28 months with a variety of collectors mounted on a spacecraft. A total of fifteen pure materials were selected as collectors based on engineering and science requirements. One of the materials was the bulk metallic glass (BMG). It was intended for collecting noble gases and solar energetic particles (SEP). This material is an amorphous metal which was custom made by C.C. Hays at the California Institute of Technology. The final glass composition is Zr58.5Nb2.8Cu15.6Ni12.8Al10.3 (in atom percent). The BMG was located on top of the wafer array mechanism and was exposed for the entire time the science canister was open (~28 months). Fortunately, the BMG did not suffer any serious damage and was intact after the Genesis canisters hard-landing into the Utah desert (Fig. 1)
Middle-up-down and top-down approaches: Strategy implementation, uncertainty, structure, and foodservice segment
This study explores the relationship between various profiles of the strategy implementation process and managers\u27 perception of the task environment, complexity and dynamism. This study addresses the following research questions: Do differences exist between levels of perceived environmental change/uncertainty and users of middle-up-down and top-down strategy implementation approaches? And, does this relationship become more meaningful when ownership, firm structure and foodservice segment characteristics are considered? There has been very little research on the food service industry that assesses the relationship between eleven task environment measures of complexity and dynamism and the use of a predominately top-down or middle-up-down approach to the implementation of strategies. Using a sample of food industry managers, multiple discriminate analysis (MDA) was used to predict the use of implementation strategies. Substantive differences appear to exist between levels of perceived environmental change/uncertainty and users of middle-up-down and top-down strategy implementation approaches for foodservice firms. The ability to correctly classify users of middle-up-down and top-down approaches using a multivariate combination of environmental variables is improved radically when ownership, firm structure, and market segment classifications were are considered. Taken as a whole, the findings are most convincing and support the basic hypotheses. Study findings indicate that a broad brushstroke approach to determining whether a middle-updown or top-down is used or appropriate based on the perceived task environment may not be valuable. The results support previous findings in other industries in that the prediction is better for market segments served and the public versus private nature of the firms involved
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