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101.
Shastin A. V. Nenajdenko V. G. Korotchenko V. N. Balenkova E. S. 《Russian Chemical Bulletin》2001,50(8):1401-1405
A new stereoselective method was developed for the synthesis of -bromostyrenes (E/Z > 5/1) starting from hydrazones of aromatic aldehydes and bromoform in the presence of CuCl. 相似文献
102.
A. Yu. Tyurin A. M. Churakov S. L. Ioffe Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》1997,46(3):592-594
The reactions of 1-aryl-2-bromodiazene 1-oxides with HCl in nonaqueous media give aryldiazonium chlorides, while 1,3,3-substituted
triazenes-1 are formed in the reactions with secondary amines. Using 2-{15N} label, it was shown that the aryl group does not migrate in these reactions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 613–615, March, 1997. 相似文献
103.
Colourless single crystals of [Hg(OH)](NO3)(H2O) were obtained by slow evaporation of an aqueous solution of Hg(NO3)2 and Bi(NO3)3. The crystal structure (orthorhombic, Pbca, Z = 8, a = 943.2(2), b = 697.6(1), c = 1349.0(2) pm, R1(all) = 0.0780) contains [Hg(OH)] = …OH–Hg–OH–Hg… zig zag chains (O–Hg–O angle: 168°, Hg–O–Hg angle: 112°, Hg–OH distance: 212 pm) to which one water molecule is attached loosely. The [Hg(OH)](H2O) chains are connected via bis‐monodentate‐bridging nitrate ions to corrugated layers that are stacked in the [001] direction. Hg2+ has an effective 2+2+2(+1) coordination. 相似文献
104.
A. Kolker L. P. S. Safonova A. N. Kinchin G. A. Krestov 《Journal of solution chemistry》1990,19(10):975-994
Experimentally determined are the enthalpies of solution of 12 electrolytes (LiBr, LiI, NaBr, NaI, NaBPh4, Et4NCl, Et4NBr, Pr4Br, Bu4NBr, Am4NBr, Ph4PCl, Ph4PBr) in ethanol at –50 to 55°C. sHo values obtained on the basis of four different extrapolation equations are analyzed. The effect of temperature changes on the thermodynamic parameters of solvation indindividual ions are calculated using thermodynamic data for the salt crystals (lattice) with the assumption that solvC
p
o
(Ph4P+)=solvC
p
o
(Ph4P-). 相似文献
105.
以Ce ZrO2为基体,通过复合不同加入量的第二相CePO4颗粒,研究了陶瓷材料力学性能的变化,并借助加载能谱仪(EDS)的扫描电子显微镜(SEM)对材料弯曲断口及压痕裂纹扩展方式进行分析。当CePO4加入量为25%时,虽然材料力学性能有一定下降,但已经能用WC刀具进行加工。材料的弯曲断口显示,CePO4在两相体系中的断裂呈层片状形式;加入CePO4后,由于两相之间弱结合界面的存在,压痕裂纹扩展形式发生明显变化,由连续扩展机制过渡为不连续扩展。由这两种机制形成的材料断裂过程是阶段性的,在实际中可以用作材料最终破坏前的预报。 相似文献
106.
The thermal analysis of CoC2O4·2H2O, Co(HCOO)2·2H2O and Co(CH3COO)2·4H2O was carried out with simultaneous TG-DTG-DTA measurements under non-isothermal conditions in air and argon atmospheres.
The intermediates and the end products of decomposition were characterised by X-ray diffraction and IR and UV-VIS spectroscopy.
The decomposition of the studied compounds occur in several stages. The first stage of dissociation of each compound is dehydration
both in air and argon. The next stages differ in air and argon. The final product of the decomposition of each compound in
air is Co3O4. In argon it is a mixture of Co and CoO for cobalt(II) oxalate and cobalt(II) formate but CoO for cobalt(II) acetate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
107.
A. V. Lesiv S. L. Ioffe Yu. A. Strelenko V. M. Danilenko 《Russian Chemical Bulletin》2004,53(10):2233-2240
Coupling of N,N-bis(silyloxy)enamines with tertiary amines and nitrogen-containing heterocycles affording the corresponding functionalized ammonium or iminium salts was studied. The area of its application was determined, and optimal procedures for the synthesis of the target products were proposed. The mechanism including the formation of conjugated nitroso alkene or a silylnitrosonium cation as key intermediates is discussed.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2137–2143, October, 2004. 相似文献
108.
109.
Xin Wang 《Journal of organometallic chemistry》2005,690(12):2934-2940
Preparation of two imidazolium salts, two monomeric nickel(II) and one cobalt(II) complexes bearing imidazolium ligands is described, The solid-state structures of these compounds have determined by single-crystal X-ray diffraction. After activation with methylaluminoxane (MAO) the nickel complexes show moderate catalytic activities of up to 6 × 105 g PE mol−1Ni h−1 for polymerization of ethylene. Catalytic activities, molecular weights have been investigated under the various reaction conditions. 相似文献
110.
Vladimir A. KaminskiiOleg Yu. Slabko Andrey V. Kachanov Boris V. Buhvetskii 《Tetrahedron letters》2003,44(1):139-140
A simple and convenient route for the synthesis of 1,1,2,3,3-pentacyanopropene salts is reported. These salts are formed by interaction of malononitrile with SeO2 in presence of organic N-containing bases or pyridinium salts. 相似文献