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11.
YANG Hong-Tao LIU Jun GENG Qing-Xi LIU Chang-Qin ZHANG Pin GAO Xiao-Yu ZHA Min JING Gui-Ru JING Cai-Liu ZHU Qing-Qi Cheung T Leung K NG L 《中国物理C(英文版)》2006,30(6):497-500
The lg Ne-Nμ relationship has been studied from 4.4×104 events (total observation time is 2.9×106s)collected from Mt. Liang Wang Array (24.5°N, 102.9°E, 2720m above sea level). In order to study the mass composition at the knee, Monte-Carlo simulations for the EAS development and detection under same event selection criteria as used in the experimental data have been performed. The result shows that the mass composition of primary cosmic rays has no obvious change and the dominant component is light nuclei around the knee. 相似文献
12.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
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NG Seik Weng 《结构化学》2014,(2)
The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis(diethyldicarbamato)nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [(3-formyl-4- hydroxyphenyl)methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5'(based on a combined set of diffraction indices) and PLATON(based on one set of diffraction indices) routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{(E)-(4-aminophenyl)diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly. 相似文献
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NG Seik Weng 《结构化学》2010,29(10):1584-1586
Dimethyltin dichloride-dibenzyl sulfoxide,((CH3)2SnCl2·O=S(CH2C6H5)2),crystallizes in the orthorhombic space group P212121 with a superstructure of dimensions a = 11.9290(1),b = 19.50490(1),c = 55.7390(6) ; Z = 28. The geometry of the five-coordinated tin atom in each of the seven independent adduct molecules is a square pyramid that is displaced towards a cis-trigonal bipyramid; the extent of displacement along the Berry pseudorotation pathway ranges from 20 to 45%. 相似文献
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Presented is a study of the general features of rotationally inelastic atom-symmetric top collision systems. This was made possible by employing a newly-developed exponential distorted wave procedure to calculate cross sections rapidly and accurately. It is demonstrated that consideration of the symmetry properties of symmetric tops leads to a reduction in the dimensionality of scattering equations and significant labor savings. Physical trends observed in cross sections and rate constants are shown to be understandable in terms of energetic and coupling concepts. 相似文献
20.
Alan R. Katritzky Richard D. Tarr Steven M. Heilmann Jerald K. Rasmussen Larry R. Krepski 《Journal of polymer science. Part A, Polymer chemistry》1988,26(12):3323-3336
The following reactions of pyrylium salts with amines are described: (1)bis(pyrylium salts) with amines; (2) diamines with pyrylium salts; and (3) bis(pyrylium salts) with diamines. Both (1) and (2) give bis(pyridinium salts) in high yields, and (3) gives the corresponding polymers which are isolated and characterized. This procedure was applied to cationic bis(pyrylium salts) to give cationic dimers and polymers, and further to zwitterionic bis(pyrylium salts) to yield the corresponding zwitterionic dimers and polymers. 相似文献