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91.
J. Wright D.C. Darvill M. Davenport F. Foster G. Hughes J.V. Morris J. Allison B. Dickinson S. Hill M. Ibbotson A. Latham H.E. Mills K. Stephens R. Thompson O. Vapenikova 《Nuclear Physics B》1981,181(3):403-420
The ratio of π? to π+ electroproduction cross sections from deuterons has been measured in the resonance region at an average four-momentum transfer squared of 0.5 (GeV/c)2. Results are presented over a wide range of pion production angles and comparisons are made with theoretical predictions based on SU(6)w symmetry and the Melosh transformation. 相似文献
92.
In this article we examine the electron emission accompanying the fracture of filled elastomers, where in previous work we have shown the emission to be intense and due predominately to interfacial failure. In this study we show that there is a strong velocity dependence on the rate of electron emission during the propagation of a crack in filled silicone rubber and polybutadiene filled with glass beads. This dependence cannot be explained by a simple proportionality between emission rate and rate of surface area production. We propose that the concentration of free radicals produced by crack propagation increases rapidly with crack velocity which in turn produces more intense electron emission by a chemiemission mechanism. 相似文献
93.
94.
R.O. Ansell T. Dickinson A.F. Povey P.M.A. Sherwood 《Journal of Electron Spectroscopy and Related Phenomena》1977,11(3):301-313
The relative photoionisation cross-sections of the tin 3d and 4d electrons are determined and combined with angular variation studies to establ 相似文献
95.
96.
97.
Potentiostatic polarisation studies have been made on iron in 10% Na2SO4 at sweep rates of 0.3–30 mV s?1 and at temperatures of 20–200°C using a platinum-platinum oxide reference electrode. The sweeps showed characteristic features of anodic dissolution and passivation. Oxide removal was evident on the cathodic sweeps. As noted by previous workers two anodic dissolution peaks were observed with clean electrode surfaces, but only one occurred when the surface was covered with oxide. The number of dissolution peaks was also found to depend on sweep rate. In contrast to other work which suggested that there was no passive region above 95°C, passivation was shown to occur even at 200°C. 相似文献
98.
The mastering and replication of video discs is described. Mastering involves exposing a photoresist-coated plate to a focused, modulated laser beam. After development, a layer of nickel is grown on the photoresist surface. The nickel layer forms a negative copy of the master plate. This nickel copy may then be used to emboss into plastic sheet a positive replica of the original master. This paper emphasizes the critical parameters involved in the process. 相似文献
99.
T. Dickinson A.F. Povey P.M.A. Sherwood 《Journal of Electron Spectroscopy and Related Phenomena》1973,2(4):441-447
An ESCA study of some “intermediate” conductors demonstrates a differential charging effect when the sample block is biased. The variation of the intensity and width of the peak from silver 3d electrons in silver iodide is used to show how the flux of the beam, the conductivity of the sample, the size and polarity of the bias and the grid mounting alter the effect. The results suggest that in unbiased samples differential sample charging contributes significantly to the width of peaks. 相似文献
100.
The decomposition of formic acid was studied on a clean Ru(101̄0) surface adsorption temperature between 100 and 460 K by means of flash thermal desorption. The decomposition products observed were H2, CO2, H2O and CO. HCOOH itself was also desorbed, although at low exposures no formic acid was observed. The H2 and CO2 products were desorbed in identical first order peaks, with a peak temperature of 395 K. The H2O product desorbed in a second order peak at 813 K, in contrast to H2O desorption from low coverage H2O adsorption which occurs in two peaks in the region of 220 and 265 K. The CO product desorbed in a first order peak at 488 K, identical to CO from CO adsorption. The dependence of the product peaks on adsorption temperature of the Ru surface was also studied. These results suggest a model involving the formation and decomposition of a surface intermediate species. 相似文献