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111.
Prompt lepton production in hadron collisions is explained in a cluster production model, by assuming that the clusters have a small branching ratio for decay into leptons. The production of low mass and small momentum clusters, normalized to reproduce pionization, can explain the observed large increases of e/π ratio for decreasing pbdT at large angles and the decreasing values of ω/π with increasing xlab near the forward direction. The present model predicts a large increase of the e/ω ratio near the forward direction as xlab increases. 相似文献
112.
113.
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
114.
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
115.
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
116.
117.
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
118.
R H Sarma C H Lee F E Evans N Yathindra M Sundaralingam 《Journal of the American Chemical Society》1974,96(23):7337-7348
119.
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
120.
K S R Sarma K L Narasimham K Premchand S Bhuloka Reddy K Parthasaradhi V Lakshminarayana 《Pramana》1982,18(6):485-494
Total photon mass attenuation coefficients in C, Al, S, Ti, B2O3, LiF, ZnO, Y2O3 and H8O2C5 (perspex) are measured on a good geometry set-up using proportional counter, Si(Li) and Ge(Li) detecting systems in the energy
region from 6.47 to 52.014 keV employing x-rays and gamma rays from radioactive sources. The deduced photoelectric cross-sections
are found to agree with the theoretical values of Storm and Israel, Scofield and semiexperimental values of Veigele wherever
available within a few percent. The photo-electric cross-sections in elements, S, Ti and Y at their respectiveK-edges obtained by extrapolation technique agree with the theoretical values of Storm and Israel and Scofield at the respectiveK-edges except in S. In the case of S both the theoretical values atK-edges are found to be underestimations, more in the case of Scofield evaluations. 相似文献