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91.
Koosam Mahendar A. V. S. Sarma P. Raghavaiah Mannepalli Lakshmi Kantam Kenneth J. Klabunde 《Helvetica chimica acta》2011,94(8):1533-1542
Aldol‐type reaction between electron deficient aldehydes and sulfonium salts to afford the corresponding β‐hydroxy α‐sulfanyl esters in moderate‐to‐good yields by using nanocrystalline MgO is described. The sulfanyl group is a useful group for further transformations in organic synthesis. Low Rf‐value isomer is anti‐configured as revealed by X‐ray diffraction study and consistent with the assignment of 1H‐NMR spectrum. 相似文献
92.
93.
The ruthenium(II) complex [RuI2(Me2SO)4] was synthesized and characterized. The Me2SO ligands are all S-bonded. Reactions of RuI2(Me2SO)4 with ligands containing P, N and S donor atoms have been carried out and the complexes obtained were characterized using different physical methods. [RuI2L4] (L= CH3CN, Me2SO and py), [RuI2(CH3CN)2(PPh3)2] and [RuI2(CS)(PPh3)3] have been synthesized using RuI3 as the source material and characterized as above. 相似文献
94.
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
95.
96.
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
97.
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
98.
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
99.
100.
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