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991.
Nagata, I., Tamura, K. and Tokuriki, S., 1982. Excess enthalpies for the systems acetonitrile-benzene-tetrachloromethane and acetonitrile-dichloromethane-tetrachloromethane at 298.15 K. Fluid Phase Equilibria, 8: 75-86Excess enthalpies at 298.15 K are reported for the binary mixtures acetonitrile-benzene, acetonitrile-tetrachloromethane, benzene-tetrachloromethane, acetonitrile-dichloromethane and dichloromethane-tetrachloromethane, and for the ternary mixtures acetonitrile-benzene-tetrachloromethane and acetonitrile-dichloromethane-tetrachloromethane. The results are analysed by means of an associated-solution theory which includes two types of self-association for acetonitrile, the formation of binary complexes CH3CN·C6H6, CH3CN·CH2Cl2 and C6H6·CCl4, and a physical-contribution term expressed by the NRTL equation. 相似文献
992.
993.
Noritaka Miyoshi Tetsuya Yamamoto Nobuaki Kambe Shinji Murai Noboru Sonoda 《Tetrahedron letters》1982,23(46):4813-4816
Treatment of ketones or aldehydes with selenium dioxide and diphenyl diselenide in the presence of acid catalyst afforded the corresponding α-phenylselenenyl carbonyl compounds in good yields. 相似文献
994.
By applying the path integral method to two interacting systems, we derive a novel form of the semiclassical quantization rule including the topological phase which was recently found in certain quantum adiabatic processes. 相似文献
995.
Shinji Fujimoto Hajime Ohtani Shin Tsuge 《Fresenius' Journal of Analytical Chemistry》1988,331(3-4):342-350
Summary Thermal degradation of various polysiloxanes was studied by pyrolysis-gas chromatography with a fused silica capillary column. The peak identification was carried out by a directly coupled gas chromatography-mass spectrometry system. Generally, polysiloxanes were thermally degraded to cyclic oligomers along with a small amount of the compounds formed through elimination and/or recombination of the pendent substituents. Most of the degradation products including possible stereo- and structural isomers were completely separated in the high-resolution pyrograms which reflect the original stereoregularities and sequence distributions in the polysiloxane chains. Furthermore, relative peak intensities of the characteristic cyclic oligomers observed were successfully interpreted in terms of the compositions of some kinds of siloxane copolymers.
Dedicated to Prof. Dr. W. Fresenius on the occasion of his 75th birthday 相似文献
Charakterisierung von Polysiloxanen durch hochauflösende Pyrolyse-GC-MS
Dedicated to Prof. Dr. W. Fresenius on the occasion of his 75th birthday 相似文献
996.
A CB(v,k,λ) means a cyclic 2-design of block size k coincidence number λ, and with v points. In this paper, a recursive construction of a CB(v,k,λ) from two or three cyclic 2-designs is given. 相似文献
997.
Selenocarboxamides have been found to be efficient reagents for converting epoxides into olefins stereospecifically in high yields under mild conditions. 相似文献
998.
A π‐conjugated polymer‐iridium complex containing the ligand in the main chain was synthesized by the Suzuki coupling method, and was applied to organic light‐emitting devices (OLEDs) as the emitter material. The polymer‐iridium complex showed red photoluminescence and electroluminescence with the maximum external quantum efficiency of ca. 3% by using 4,4′‐N,N′‐dicarbazole‐biphenyl and 2‐(4‐biphenylyl)‐5‐(4‐tert‐butyl‐phenyl)‐1,3,4‐oxadiazole blended into the polymer emitter layer. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
999.
1000.
Given ann × n matrixM and ann-dimensional vectorq, the problem of findingn-dimensional vectorsx andy satisfyingy = Mx + q, x 0,y 0,x
i
y
i
= 0 (i = 1, 2,,n) is known as a linear complementarity problem. Under the assumption thatM is positive semidefinite, this paper presents an algorithm that solves the problem in O(n
3
L) arithmetic operations by tracing the path of centers,{(x, y) S: x
i
y
i
= (i = 1, 2,,n) for some > 0} of the feasible regionS = {(x, y) 0:y = Mx + q}, whereL denotes the size of the input data of the problem. 相似文献