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11.
12.
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
13.
14.
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
15.
研究了酚醛型吸附树脂JDW 2在非水体系中对吡啶和N ,N 二甲基苯胺的静态吸附 .由实验结果推论正己烷中树脂对吡啶和N ,N 二甲基苯胺的吸附是以氢键吸附机理为主进行的 ,JDW 2酚醛型吸附树脂在正己烷中 ,等温吸附吡啶和N ,N 二甲基苯胺的平衡吸附数据符合Langmuir方程 ,相关系数在 0 99以上 ,因此 ,酚醛型吸附树脂在正己烷中吸附吡啶和N ,N 二甲基苯胺属单分子层吸附 ;同时对非水体系中乙醇或乙酸乙酯的含量对树脂吸附吡啶和N ,N 二甲基苯胺的影响进行了研究 相似文献
16.
The title compound,[Cu2(CH3COO)4(C8H10N2)]n·nCH3CN1 (C8H10N2,4,4'-bipy = 4,4'-bipyridine),has been solvothermally synthesized in CH3CN and characterized by X-ray diffraction.The crystal is of monoclinic,space group Cc with a = 22.626(6),b = 14.012(4),c =15.106(4) (A),β = 107.610(3)°,V = 4565(2) (A)3,C20H23Cu2N3O8,Mr = 560.49,Z = 8,Dc = 1.631 g/cm3,μ = 1.914 mm-1,Flack parameter = 0.48(1),F(000) = 2288,R = 0.042 and wR = 0.)98 for 8887 observed reflections (I > 2σ(I)).It consists of nearly linear one-dimensional chains [Cu2(CH3COO)4(C8H10N2)]n derived from paddle-wheel [Cu2(CH3COO)4] unit linked by 4,4'-bipy,and CH3CN as guest molecule regularly decorates between the chains. 相似文献
17.
In this study, a variational approach to the settlement analysis of an axially loaded pier embedded in a multi-layered soil
profile is presented. In this method, the soil profile and the embedded pier are divided into a number of sub-layers according
to the actual number of soil layers observed in the field. The displacement shape function of each soil layer is given as
a product of an exponential equation along the pier depth and the Bessel's solution in the radial direction. The displacement
relationship among the layers can be derived through the transformation matrices. One of the major features of this method
is that the total number of pier elements is the same as that of soil sub-layers. All the field components, such as the displacement,
stress, and strain in the soil, can be calculated by closed-form solutions except that the only unknown variable is the value
β which can be determined by iteration techniques. Comparisons were made with the results of finite element analysis and the
field observation in pile-loaded tests. 相似文献
18.
We report on a study of the proton induced hyperon production reactions. We discuss the theoretical efforts made towards understanding
the existing data and the uncertainties involved in the calculations. Our recent calculations of the missing mass spectra
for the pp → K
+ Λp reaction which involve a proper coupled channel treatment of the final state Λp interaction are presented. Significant differences in the results using different models of the hyperon-nucleon interaction
are found. 相似文献
19.
20.
I. P. Denissova 《Theoretical and Mathematical Physics》1997,112(3):1199-1207
A particular solution of the equations of the relativistic theory of gravity describing the gravitational field of an infinitely
thin source arranged along the z-axis is obtained by the indefinite coordinate method. In this field, the motion of massive
particles is studied.
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 112, No. 3, pp. 501–512, September, 1997. 相似文献