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891.
近年来对溶剂革取过程中有机相形成微乳状液的研究正引起人们的重视同,我们曾用付里叶变换红外光谱法研究过钢皂及钾皂2一乙基已基股酸单·2一乙基已基酯(简写为NaA及KA下同)加水形成微乳状液的过程,观察到P二0,P-0-C,P-0-HH-0-H和0-H等基团吸收谱带频率或强度的变化[‘剑.本文进一步对#、销和钾三种碱金属皂化2一乙基已基胁酸单一2一乙基已基酯有机相微乳状液的形成及其红外光谱作深入研究.1实验部分五.1样品的制备问将金属捏、销和钾各置于2一乙基巴基磷酸单一2一乙基已基酯(以HA表示,下同)一正庚烷中加热回流… 相似文献
892.
893.
ZHU Jun ZHANG Yun CHEN Hao CHE Yun-Xia ZHENG Ji-Min ② 《结构化学》2006,25(8):1011-1013
1 INTRODUCTION Nonlinear optics (NLO) is at the forefront of cur- rent researches because of its importance in provi- ding the key functions of frequency shifting, optical modulation, optical switching, optical logic and op- tical memory for the emerging … 相似文献
894.
Gunter Zwilling 《Monatshefte für Chemie / Chemical Monthly》1981,112(2):157-165
The anodic overvoltage on carbon and platinum electrodes in the electrochemical production of high purity gadolinium from molten 75 LiF-25 mol% GdF3 solutions is discussed. At the cell temperature of 840°C calciumimpregnated anodes led to the reduction of inert electrode films and to a current yield of nearly 100%.The deposited gadolinium contained 75, 22, 54 and less than 100 ppm of the interstitial elements H, N, O and C respectively; the concentrations of the highest other analysed impurities were: Si (89), Fe (15), Y (5), Zr (3), Nd (3), Tb (71), Ta (49), W (23) and Re (<3 ppm).Partly performed at the Ames Laboratory—U.S. Department of Energy. 相似文献
895.
896.
The electronic effect on the regioselectivity in the alkynylation of phenyloxiranes was investigated using three kinds of metal acetylides. BF3 mediated lithium acetylide provided either the α- or β-alkynylated products by controlling the effect of the para-substituents of the phenyloxiranes. LiClO4 mediated lithium acetylide and titanium acetylide, on the other hand, afforded predominantly the β- and α-products, respectively. 相似文献
897.
The new Pd(II), Pt(II), Re(V), Mo(VI) and W(VI) complexes of 2-hydroxynicotinic acid (H2nicO), trans-[PdCl(HnicO)(PPh3)2]·0.75CH3CN (1), K[PdCl(HnicO)2]·H2O (2), [Pd(HnicO)2(bipy)] (3), cis-[PtCl(HnicO)(PPh3)2]·0.75CH3OH·0.5H2O (4), [PtCl(HnicO)(bipy)] (5), cis-[ReOI2(HnicO)(PPh3)] (6), Na2[Mo2O6(HnicO)2]·5H2O (7), Na2[Mo4O12(HnicO)2]·2H2O (8) and Na2[W2O6(HnicO)2]·5H2O (9) have been prepared. The crystal structures of 1 and 4, were determined by X-ray diffraction and show the HnicO− ligand coordinated to palladium or platinum through the nitrogen atom only. Infrared, Raman, 1H and 13C{1H} NMR spectroscopic data for the complexes are presented and are in agreement with the crystallographic results. 相似文献
898.
J. Baran A. J. Barnes M. K. Marchewka A. Pietraszko H. Ratajczak 《Journal of Molecular Structure》1997,416(1-3):33-42
The crystal structure of bis(betaine)-selenic acid has been determined by X-ray diffraction as orthorhombic, space group Pbca, with a = 11.591(2), b = 22.930(5), c = 12.045(2) Å and Z = 8. The crystal comprises hydrogen selenate ions, HSeO−4, and two distinct betaine molecules, which are held together into a complex by short hydrogen bonds. One of the betaine molecules is present as the zwitterion form (CH3)3N+---CH2---COO− and the second occurs as the protonated form (CH3)3N+---CH2---COOH. Powder FTIR and Raman spectra were measured. An assignment of the observed bands to vibrations of the hydrogen bonds and internal vibrations of the hydrogen selenate ion and the betaine molecules is proposed. 相似文献
899.
用从头计算方法对硝基氢(HNO2)体系的异构化及分解反应进行了研究,在6-31G水平上,该化合物异构化为反式来酸的势垒为292kJ/mol,且不易分解为H+NO2或O+HNO。 相似文献
900.
Ab initio calculations on vinyldifluoroborane yield a -contribution of 23 kJ/mol (5.5 kcal/mol) mainly due to the C=C bond and not to the lone pairs of the fluorine atoms. The rotational barrier was also determined. The force field calculations favour the interpretation of the bond structure derived from the theab initio results. 相似文献