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91.
Sunil H. Chaki Mahesh D. Chaudhary M. P. Deshpande 《中国物理快报》2014,(10):89-92
Single crystals of pure SnS, indium (In) and antimony (Sb) doped SnS are grown by the direct vapor transport technique. Two doping concentrations of 5 at. % and 15 at. % are employed for both In and Sb dopants. In total, five samples are studied, i.e., pure SnS, 5at.% In-doped SnS, 15at.% In-doped SnS, 5at.% Sb-doped SnS and 15at.% Sb-doped SnS single crystals. The energy dispersive analysis of x-ray (EDAX) and x-ray diffraction (XRD) analysis show that all the five as-grown single crystal samples possess near perfect stoichiometry and orthorhombic structure, respectively. The doping of In and Sb in SnS is established from the EDAX data and from the shift in the peak positions in XRD. Photoeleetroehemical (PEC) solar cells are fabricated by using the as- grown single crystal samples along with iodine/iodide electrolytes. Mott-Schottky plots for different compositions of iodine/iodide electrolytes show that O. 025 M 12 + 1 M Nal+2 M Na2 S04 +0.5 M 1-12 S04 will be the most suitable electrolyte. Study of efficiency (η) and fill factor for different intensities of illuminations at room temperature is carried out for the five samples. The In-doped SnS single crystals show better PEC efficiency than the undoped and Sl〉doped SnS single crystals. 相似文献
92.
Z. Wei V.S. Deshpande K.P. Dharmasena H.N.G. Wadley R.K. Elzey Y. Chen K. Kiddy 《Journal of the mechanics and physics of solids》2008,56(5):2074-2091
The responses of metallic plates and sandwich panels to localized impulse are examined by using a dynamic plate test protocol supported by simulations. The fidelity of the simulation approach is assessed by comparing predictions of the deformations of a strong-honeycomb-core panel with measurements. The response is interpreted by comparing and contrasting the deformations with those experienced by the same sandwich panel (and an equivalent solid plate) subjected to a planar impulse. Comparisons based on the center point displacement reveal the following paradox. The honeycomb panel is superior to a solid plate when subjected to a planar impulse, but inferior when localized. The insights gained from an interpretation of these results are used to demonstrate that a new design with a doubly-corrugated soft core outperforms solid plates both for planar and localized impulses. 相似文献
93.
The dynamic response of fully clamped, monolithic and sandwich plates of equal areal mass has been measured by loading rectangular plates over a central patch with metal foam projectiles. All plates are made from AISI 304 stainless steel, and the sandwich topologies comprise two identical face-sheets and either Y-frame or corrugated cores. The resistance to shock loading is quantified by the permanent transverse deflection at mid-span of the plates as a function of projectile momentum. At low levels of projectile momentum both types of sandwich plate deflect less than monolithic plates of equal areal mass. However, at higher levels of projectile momentum, the sandwich plates tear while the monolithic plates remain intact. Three-dimensional finite element (FE) calculations adequately predict the measured responses, prior to the onset of tearing. These calculations also reveal that the accumulated plastic strains in the front face of the sandwich plates exceed those in the monolithic plates. These high plastic strains lead to failure of the front face sheets of the sandwich plates at lower values of projectile momentum than for the equivalent monolithic plates. 相似文献
94.
Dynamic mechanical studies of cholesteric liquid crystalline substances in the solid state have been reported using Du Pont's Dynamic Mechanical Analyser, DMA-981. All the substances showed multiple transitions. There is no common transition though the parent structure was similar in the compounds. These weak transitions are not detectable by DSC and hence appear to be second order transitions possibly arising due to rotation of the molecules around the long axis. Alternatively the lattice defects may also be responsible for such transitions. 相似文献
95.
N. G. Deshpande 《Pramana》2003,60(2):353-362
We briefly discuss measurements of angles β and α of the unitarity triangle. We then review rate asymmetries usingSU(3) relationships in the standard model (SM). Some methods to measure angle y usingSU(3) are then discussed. We note that rate forb →
sγ can be used to set limits on extra dimensions in which standard model particles propagate. 相似文献
96.
B. D. Gupta S. Deshpande † R. E. Jones T. J. Borys E. W. Abrahamson ‡; 《Photochemistry and photobiology》1986,43(5):529-533
Abstract— A fast light-induced light scattering transient in the presence of Mg2+ and GTP is observed from bovine rod outer segment suspension. This transient is studied at various temperatures, degrees of photo-bleaching and GTP concentration. The kinetic analysis of this signal at low photo-bleaching (∼ 5%) reveals two different processes which are consecutive rather than simultaneous. The rate of both processes depends upon the extent of photo-bleaching and indicates that each process requires a photolyzed rhodopsin intermediate. At low temperature, the rate constant of both the processes increases with the extent of photo-bleaching while at higher temperatures it decreases. The calculated activation energy of both processes decreases with increasing photo-bleaching. It has also been observed that with decreasing GTP concentration, the rates of both processes decrease indicating that the two processes though first order are most likely bimolecular, first order in both GTP and the photolytic rhodopsin intermediate (metarhodopsin II) 相似文献
97.
The dielectric relaxation studies of 4-ethylphenol-methanol mixtures have been carried out at various temperatures ranging
from 10°C to 40°C using time domain reflectometry in the frequency range 10 MHz to 10 GHz. The relaxation mechanism in these
systems is explained by Cole-Davidson model. The excess dielectric parameters, Kirkwood correlation factor and activation
energy have been calculated and discussed with respect to molecular arrangements, and microdynamics of the binary mixture
composed of both the associative type of liquids. 相似文献
98.
We have studied five-dimensional homogeneous cosmological models with variableG and bulk viscosity in Lyra geometry. Exact solutions for the field equations have been obtained and physical properties of
the models are discussed. It has been observed that the results of new models are well within the observational limit. 相似文献
99.
100.