A metal plate Fresnel lens antenna with aperture dimensions 12 ft \times 12 ft , and fed by a pyramidal horn has been built for satellite TV reception at 4 GHz. When used with a commercial receiver equipped with a 120...
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A metal plate Fresnel lens antenna with aperture dimensions 12 ft \times 12 ft , and fed by a pyramidal horn has been built for satellite TV reception at 4 GHz. When used with a commercial receiver equipped with a 120K LNA it produced good video pictures from the geostationary satellite Satcom F3. We believe this to be the first application of a Fresnel lens antenna for ground-based satellite TV reception.
We investigate the impact of quantum well (QW) thickness on efficiency loss in c-plane InGaN/GaN LEDs using a small-signal electroluminescence (SSEL) technique. Multiple mechanisms related to efficiency loss are indep...
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Charge dependent directed flow is an important observable of electromagnetic fields in relativistic heavy-ion collisions. We demonstrate how the difference in charge dependent directed flows between protons and antipr...
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ZrO2 is one of the most effective and widely used nucleating agents in various families of glass-ceramics;however, its detailed mechanism remains a subject of debate. Understanding its nucleation mechanism requires a ...
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The current study explores computational models developed using the improved Scarf potential and harmonic oscillator to simulate vibrational modes in nonlinear polyatomic systems. These models are derived from the par...
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The current study explores computational models developed using the improved Scarf potential and harmonic oscillator to simulate vibrational modes in nonlinear polyatomic systems. These models are derived from the par...
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Ternary shandite compounds with the general formula T3M2X2 (T = Ni, Co, Rh or Pd;M = Sn, In, or Pb;and X = S or Se) have emerged as a large pool of topological semimetals. This family of compounds hosts different topo...
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In light of the recent data for B¯(s)→D(s)(*)P and B¯(s)→D(s)V decays, we perform a model-independent phenomenological analysis in the presence of quasielastic rescattering. With the Wilson coefficients in...
In light of the recent data for B¯(s)→D(s)(*)P and B¯(s)→D(s)V decays, we perform a model-independent phenomenological analysis in the presence of quasielastic rescattering. With the Wilson coefficients including contributions beyond the standard model, the lifetimes of the B meson and Bd0−B¯d0 mixing are investigated to clarify correlations among the observables. We show that parameter regions for quasielastic rescattering, the size of color-suppressed tree amplitudes, and new physics are constrained due to the lifetime data. As a consequence, it is revealed that this scenario can be tested by the future LHCb measurement of the width difference in Bd0−B¯d0 mixing and semileptonic CP asymmetry.
The solar energy conversion properties of thin Si and GaP nanowire photoelectrodes in photoelectrochemical cells have been examined through sets of finite-element simulations. A discussion describing the motivation be...
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The solar energy conversion properties of thin Si and GaP nanowire photoelectrodes in photoelectrochemical cells have been examined through sets of finite-element simulations. A discussion describing the motivation behind nanostructured, high aspect ratio semiconductor photoelectrode designs and a brief survey of current experimental results reported for nanostructured semiconductor photoelectrodes in photoelectrochemical cells are presented first. An analysis is then shown that outlines the primary recombination pathways governing the steady-state current-potential behaviors of thin, cylindrical nanowire photoelectrodes, with explicit expressions detailing the differences between planar and cylindrical photoelectrodes arising from the solution of carrier fluxes in planar and cylindrical geometries. Results from finite-element simulations used to model the key features of thin nanowire photoelectrodes under low-level injection conditions are shown that illustrate which recombination pathway(s) is operative under various experimental conditions. Specifically, the respective effects of non-uniform doping, tapering along the length, variation in charge carrier mobilities and lifetimes, changes in nanowire radius, and changes in the density of surface defects on the observable photocurrent-potential responses are reported. These cumulative results serve as guides for future experimental work aimed at improving the attainable solar energy conversion efficiencies of doped semiconductor nanowire photoelectrodes. Lastly, separate simulations that model lightly doped nanowire photoelectrodes under high-level injection conditions are discussed. These results suggest discrete, ohmic-selective contacts may afford a way to circumvent the stringent doping requirements discussed herein for thin nanowire photoelectrodes.
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