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101.
102.
L3VV Auger transitions of copper alloys show a feature due to a band-like states, the shape and intensity of which depend on
the composition. The energy separation between this feature and the L3M4·5M4·5 peak increases progressively with Cu concentration. 相似文献
103.
A three-unit standby redundant system has been studied. All the random variables involved are discrete. The life time of a unit while online is an arbitrarily distributed random variable. Also it is assumed that the probability of the repair completion is a constant. Using the regeneration point technique, the availability of the system is derived. 相似文献
104.
Reductive removal of an allylic functional group proceeds most easily and efficiently with nickel boride as the bond being cleaved becomes a better leaving group (e.g. OCH3<OH <OSiMe3<OCOCH3<OCOCF3) 相似文献
105.
The data on the excitation functions of24Mg+24Mg elastic and inelastic (24Mg +24Mg*(2+),24Mg*(2+)+24Mg*(2+),24Mg+24Mg*(4+),24Mg*(4+)+24Mg*(2+),24Mg+24Mg*(6+)) scattering fromE c.m=42 to 56 MeV have been subjected to a statistical analysis consisting of calculations of deviation function, cross-correlation function, cross-channel correlation coefficients, coherence widths, and the distribution of cross sections. On the basis of the analysis resonant structures atE c.m=45.70, 46.65, 47.35 and 47.75 MeV have been confirmed. Two new resonant structures atE c.m=44.55 and 50.50 MeV have been identified. 相似文献
106.
107.
We investigate the possibility that in a heavy nucleus a few nucleons exist in a state of total deconfinement. The constituents of these deconfined nucleons are regarded as a mixture of quark-and gluon-gases in thermal equilibrium at a fixed temperatureT. This approach reproduces the observed softening of the valence quarks in heavy nuclei and predicts fewer gluons atx<1 and an exponential decrease of the structure functions atx>1. 相似文献
108.
This paper discusses two models of two-unit standby redundant systems in which the switchover time is a random variable and the repair facility is not available for a random time immediately after each repair completion. In model I the probability distributions of the life time of the online unit and switchover time are general while all the other distributions are exponential. Model II is a cold standby system in which the probability distributions of the “preparation time” of the repair facility is exponential and all the other distributions are general. Using the regeneration point technique the availability functions of the two systems are determined. Several special cases are also discussed. 相似文献
109.
R H Sarma C H Lee F E Evans N Yathindra M Sundaralingam 《Journal of the American Chemical Society》1974,96(23):7337-7348
110.
Zhang J Sarma KD Curran TT Belmont DT Davidson JG 《The Journal of organic chemistry》2005,70(15):5890-5895
Lewis acid catalyzed addition of active methylene compounds to mucochloric acid (1) and mucobromic acid (2) affording Knoevenagel aldol adducts, gamma-substituted gamma-butenolides, has been explored. Catalytic efficiencies of various Lewis acids have been compared. Indium acetate (0.25-5 mol %) was found to be the most efficient catalyst. 相似文献