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131.
A high pressure-high temperature cell which permitsin-situ pressure and temperature calibration is described. The cell is in an opposed anvil configuaration, and houses two samples
with four probes each along with a miniature furnace and a thermocouple. The pressure and temperature capability of the cell
are 100 kbar and 1000°C respectively. This cell was developed to study the electrical resistivity of metals and alloys at
high pressure and high temperature. Bismuth was used to calibrate the cell. We report in this paper the design details and
the performance of this cell. Ni has been chosen as a test problem and the observed behaviour is indicated to show the quality
of data. 相似文献
132.
Shadowing effects in deep-inelastic lepton-nucleus scattering probe the mass spectrum of diffractive leptoproduction from individual nucleons. We explore this relationship using current experimental information on both processes. In recent data from the NMC and E665 collaboration, taken at small x ? 0.1 and Q 2 ? 1 GeV 2, shadowing is dominated by the diffractive excitation and coherent interaction of low mass vector mesons. If shadowing is explored at small x ? 0.1 but large Q 2 ? 1 GeV 2 as discussed at HERA, the situation is different. Here dominant contributions come from the coherent interaction of diffractively produced heavy mass states. Furthermore we observe that the energy dependence of shadowing is directly related to the mass dependence of the diffractive production cross section for free nucleon targets. 相似文献
133.
Transparent conductive ZnO/Ag/ZnO multilayer electrodes having much lower electrical resistance than the widely used transparent electrodes were prepared by simultaneous RF magnetron sputtering of ZnO and DC magnetron sputtering of Ag. An Ag film with different thickness was used as intermediate metallic layers. The optimum thickness of Ag thin films was determined to be 6 nm for high optical transmittance and good electrical conductivity. With about 20-25 nm thick ZnO films, the multilayer showed high optical transmittance in the visible range of the spectrum and had color neutrality. The electrical and optical properties of the multilayers were changed mainly by Ag film properties. A high quality transparent electrode, having sheet resistance as low as 3 ohm/sq and high transmittance of 90% at 580 nm, was obtained and could be reproduced by controlling the preparation parameter properly. The above property is suitable as transparent electrode for dye sensitized solar cells (DSSC). 相似文献
134.
Bibhuti B. Samal Sagarika Sahu Braja B. Chinara S. Nanda P. K. Otta L. M. Mohapatro Trijama R. Mohanty A. R. Ray K. C. Singh 《Journal of polymer science. Part A, Polymer chemistry》1988,26(12):3159-3166
Graft copolymerization of acrylonitrile (AN) onto sisal fibers (chemically modified) was studied using the Mn(III)/EDTA redox system in aqueous solution. The effects of time, monomer (AN), metal ion [Mn(III)] substrate [ethylene diamine tetraacetic acid (EDTA)], temperature, and acid concentration on graft yield have been studied. The effects of thiourea on the graft yield has also been studied. A suitable mechanism is proposed. 相似文献
135.
136.
137.
The catalytic effect of Dy2O3 on the isothermal decomposition of sodium bromate has been investigated at 613.0 K. The data are analyzed in the light of various topochemical models. Dy2O3, being a p-type semiconductor, accelerates the decomposition of bromate by favoring the electron transfer reaction involved in the process. The plausible mechanism of the catalytic activity on the decomposition process is discussed. 相似文献
138.
The synthesis
of conducting polymers based on m-nitroaniline, m-chloroaniline and m-aminophenol
by aniline initiated ammonium peroxydisulfate oxidation, has been attempted.
The IR spectra of the polymers have been studied. Thermogravimetric analysis
of the conducting polymers has been followed using a computer analysis method
LOTUS PACKAGE, developed by us for assigning the degradation mechanism. A
number of equations have been used to evaluate the kinetic parameters. The
mechanism of degradation of the conducting polymers has been explained on
the basis of their kinetic parameters. 相似文献
139.
Keith A. Earle Laxman Mainali Indra Dev Sahu David J. Schneider 《Applied magnetic resonance》2010,37(1-4):865-880
Methods of statistical geometry are introduced which allow one to estimate, on the basis of computable criteria, the conditions under which maximally informative data may be collected. We note the important role of constraints which introduce curvature into parameter space and discuss the appropriate mathematical tools for treating curvature effects. Channel capacity, a term from communication theory, is suggested as a useful figure of merit for estimating the information content of spectra in the presence of noise. The tools introduced here are applied to the case of a model nitroxide system as a concrete example, but we stress that the methods described here are of general utility. 相似文献
140.