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71.
72.
Introduction The studies of diorganotin(IV) complexes are of current interest owing to their wide range of applica-tions such as biocides and homogeneous catalysts in industry.1 In recent years there have been more and more reports on the synthesis, antitumour activities and structural elucidation of various diorganotin(IV) deriva-tives of carboxylic acid.2-5 In particular, people take considerable interest in structural studies of diorgano-tin(IV) complexes of carboxylic acid, because there… 相似文献
73.
Jun Xiang Ge 《International Journal of Infrared and Millimeter Waves》1994,15(10):1681-1688
In 1991, we developed a new type of quasi-optical power combiner, called a compound quasi-optical power combiner, at Ka-band. In this paper, the circuit of such a compound quasi-optical power combiner is analysed. Its equivalent circuit model is proposed. The circuit equations, the balance condition, the injection locking and the stabilized condition of the compound quasi-optical power combiner are studed by the equivalent circuit model. As an example, a compound quasi-optical power combiner which consists of two single—cavity, two—device power combiners is analysed 相似文献
74.
75.
Xia Yin Weiguang Zhang Qijiao Zhang Jun Fan Chian Sing Lai Edward R. T. Tiekink 《应用有机金属化学》2004,18(3):139-140
The centrosymmetric structure of {Cd[S2CN(CH2Ph)2]2}2 features both bridging and chelating dithiocarbamate ligands so that a square pyramidal S5 coordination geometry results. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
76.
从4~10周龄药物流产胚胎的生殖嵴和肠系膜组织中分离原始生殖细胞(primordial germ cells,PGCs),培养在添加人重组白血病抑制因子(rh LIF)、人重组碱性成纤维细胞生长因子(rh bFGF)和Forskolin的小鼠饲养层细胞上.经过4~7 d培养,PGCs形成典型的鸟巢状集落.集落在传代过程中保持碱性磷酸酶活性,且胚胎阶段性特异抗原1(SSEA-1)、胚胎阶段性特异抗原3(SSEA-3)免疫荧光染色呈阳性.具有分化潜能的PGCs能在体外连续传代培养12代.结果表明从药物流产胚胎中分离的人类PGCs可以在体外培养成为具有分化潜能的多能性干细胞. 相似文献
77.
A polymerized quaternary ammonium salt polydiallyldimethylammonium chloride, exhibiting high stability to heat and base, was prepared and applied as phase-transfer catalyst (PTC) in halogen-exchange (Halex) fluorination of chloronitrobenzenes to give excellent yields of corresponding fluoronitrobenzenes. Dimethyl sulfoxide was found to be the best solvent when microwave was applied as heating resource. 相似文献
78.
Jun Jiao Lifeng Dong Sean Foxley Catherine L Mosher David W Tuggle 《Microscopy and microanalysis》2003,9(6):516-521
In this article, we report a technique for growing carbon nanotubes in a more controllable fashion, which enables us to synthesize nanotubes directly in various forms of designed patterns. This nanofabrication process is based on a combination of focused ion beam (FIB) and chemical vapor deposition (CVD) techniques. In this process, arrays of conductive patterns were first deposited on silicon substrates by directing a gaseous compound (C(9)H(16)Pt) via the capillary needle-sized nozzles within a FIB system. The substrates were then coated with catalyst and further modified by the FIB to localize the position of the catalyst. Finally, the growth of carbon nanotubes on the designed substrates was carried out by CVD of hydrocarbon gases. This fabrication technique has the advantage of positioning carbon nanotubes in selected locations. This may open up opportunities for the direct synthesis of carbon nanotubes onto almost any substrate material, thus allowing fabrication of carbon nanotube-based devices. 相似文献
79.
In the crystal of the title compound, the quinone fragment of the host (1) participates in weak D-A interactions with a neighboring naphthalene moiety of 1 and with the guest molecule via fairly short intermolecular face-to-face contacts. An intermolecular electrostatic interaction between a quinone-oxygen atom and a neighboring quinone ring is suggested by short O...C contacts. There exist several C-H...O hydrogen bonds, one of which seems to contribute to the formation of a centrosymmetric dimer of 1. 相似文献
80.
Three mechanisms to reduce threading dislocations(TDs) in GaN films as the epitaxial films grow thicker are suggested by SEM and TEM 相似文献