498 research outputs found
Surface studies of chemical vapor deposited and natural (100) diamond
The vibrational structure and phonon character of hydrogen terminated and hydrogen free polycrystalline chemical vapor deposited (CVD) diamond was investigated using high resolution electron energy loss spectroscopy (HREELS). The experiments were conducted at a variety of incident energies: 8.8 eV, 6.0 eV, 3.2 eV, and 1.5 eV. HREELS of polycrystalline CVD diamond reveals a strong band at 2900 cm-1 with two maxima and a broad shoulder on the energy loss tail. The two maxima represent monohydride stretches on {111} and {100} crystal facets, while the broad shoulder is attributed to olefinic stretches associated with defects on {111} surfaces. Three strong phonon features were observed at 400 cm-1, 700 cm-1, and 1100 cm-1. The 1100 cm-1 band is difficult to resolve from the C-H bending mode at 1200 cm-1 unless the sample is first desorbed or the incident energy lowered below 6.0 eV. It was found that the 400 cm-1 band continued to increase in intensity as the beam energy was lowered. No compelling evidence of energy dependent dispersion was observed for any of the phonon bands.
The chemistry of chlorine interacting with CVD diamond films and natural C(100) diamond was also investigated. The reaction of the CVD surface with atomic chlorine removes all monohydride vibrational structure except that associated with {111} defects, whose intensity remains unchanged. Only a small feature near 800 cm-1 is evident as a possible C-Cl stretch. Auger spectroscopy and secondary ion mass spectrometry (SIMS) confirm the presence of chemisorbed chlorine on both C(100) and CVD diamond. Auger spectroscopy reveals a strong preference for chlorine addition to {100} facets, but the only detectable chlorine containing species as noted by SIMS is C2H4Cl+ for both C(100) and CVD diamond. It is suggested that chlorine primarily adsorbs to {100} surfaces by substituting for surface hydrogen, whereas sp2 hydrogen terminated defects near 3000 cm-1 appear to be unreactive to chlorine substitution.
Water has been implicated as important in low temperature growth of CVD diamond with oxygen addition. Water has also been reported to react dissociatively with diamond (100) single crystal and diamond powder to produce hydroxyl, ether, and carbonyl surface groups. The reactivity of water with hydrogen free CVD diamond was investigated using high resolution electron energy loss spectroscopy and Auger electron spectroscopy. No evidence was found for a dissociative reaction. In an effort to increase the functionality of diamond toward water addition, the CVD samples were first reacted with atomic chlorine. Again no evidence was noted of water dissociation on diamond. The chlorine terminated diamond surface was also reacted with molecular methanol, and once again no evidence of hydroxyl termination was observed. The temperature dependence of the C1 Auger signal was compared with the results of water and methanol addition. It was observed that any chlorine loss could be explained by simple thermal desorption rather than a chemical interaction between the C1 terminated diamond surface and dose gas
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A computer-based application for core course outcomes assessment and program continuous improvement using an integrative business plan — an empirical evaluation
Outcomes assessment and continuous program improvement has become an increasingly important topic in higher education. ASCSB and governmental bodies often require this type of self-analysis. This paper presents and examines a model of business common core course assessment and improvement using an integrated business plan in the upper division strategic management capstone course. An emphasis is placed demonstrating how computer and information technology is used for instruction and as a means for outcomes assessment. Also, an evaluation of empirical data developed over a one-year period is presented. The manuscript also reflects on some of the problems and issues engendered by any formal and required outcomes assessment program. It is the authors hope that this approach will serve as one model in the development of outcomes assessment and quality control programs in Colleges of Business Administration
Matched detectors as definers of force
Although quantum states nicely express interference effects, outcomes of
experimental trials show no states directly; they indicate properties of
probability distributions for outcomes. We prove categorically that probability
distributions leave open a choice of quantum states and operators and
particles, resolvable only by a move beyond logic, which, inspired or not, can
be characterized as a guess. By recognizing guesswork as inescapable in
choosing quantum states and particles, we free up the use of particles as
theoretical inventions by which to describe experiments with devices, and
thereby replace the postulate of state reductions by a theorem. By using the
freedom to invent probe particles in modeling light detection, we develop a
quantum model of the balancing of a light-induced force, with application to
models and detecting devices by which to better distinguish one source of weak
light from another. Finally, we uncover a symmetry between entangled states and
entangled detectors, a dramatic example of how the judgment about what light
state is generated by a source depends on choosing how to model the detector of
that light.Comment: 30 pages, 4 figs, LaTeX; new Introduction; new material in Secs. 4 &
5; new Sec. 6; 1 new figure, added reference
Parallel FPGA Programming over Backplane Chassis
For systems with a large number of FPGAs, where a design is instantiated across multiple FPGAs in a chassis, an efficient mechanism of programming the FPGA devices is needed. The mechanism described herein allows multiple FPGAs to be programmed across a backplane. Only a single configuration PROM is required to store the configuration for the multiple instances of the design. When the system boots, all FPGAs are programmed in parallel. This design is applicable to any system which contains a multiple board system which has instances of identical FPGA implementations distributed across the boards. Signal integrity of signals is considered
The Otterbein Miscellany - May 1965
https://digitalcommons.otterbein.edu/miscellany/1011/thumbnail.jp
Exile Vol. III No. 1
The Dreamer by Jesse Matlack 8-11
And Now a Response by John Kenower 12-16
Two Scenes from a Play by Robert Whitlatch 17-21
The Urgency of the Situation by Jim Gallant 22-23
James Branch Cabell by Robert Canary 24-29
Was Rasselt Im Stroh by Carol Dugle 30-31
Three Stops for an Artist by Nicos Stangos 32-36
POETRY
Of Darkness by Burnell Chaney 16
Wolf in Sheep\u27s Clothing by Ellen Moore 21
Fresh Snow OR The Stars Have Fallen by Thomas Turnbull 29
When I Left Home by Yoko Kuyama 37
Standing Under a Tall Bare Tree by Yoko Kuyama 38
I Have Been Alone Too Long by Ellen Moore 40
Dirge: For Myself by Ellen Moore 40
In this issue the editors of EXILE are proud to publish Three Stops for an Artist by Nicos Stangos. This story has been awarded the semi-annual Denison Book Store - EXILE Creative Writing Prize
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