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991.
Dinuclear iron(II)-cyanocarbonyl complex [PPN](2)[Fe(CN)(2)(CO)(2)(mu-SEt)](2) (1) was prepared by the reaction of [PPN][FeBr(CN)(2)(CO)(3)] and [Na][SEt] in THF at ambient temperature. Reaction of complex 1 with [PPN][SEt] produced the triply thiolate-bridged dinuclear Fe(II) complex [PPN][(CN)(CO)(2)Fe(mu-SEt)(3)Fe(CO)(2)(CN)] (2) with the torsion angle of two CN(-) groups (C(5)N(2) and C(3)N(1)) being 126.9 degrees. The extrusion of two sigma-donor CN(-) ligands from Fe(II)Fe(II) centers of complex 1 as a result of the reaction of complex 1 and [PPN][SEt] reflects the electron-rich character of the dinuclear iron(II) when ligated by the third bridging ethylthiolate. The Fe-S distances (2.338(2) and 2.320(3) A for complexes 1 and 2, respectively) do not change significantly, but the Fe(II)-Fe(II) distance contracts from 3.505 A in complex 1 to 3.073 A in complex 2. The considerably longer Fe(II)-Fe(II) distance of 3.073 A in complex 2, compared to the reported Fe-Fe distances of 2.6/2.62 A in DdHase and CpHase, was attributed to the presence of the third bridging ethylthiolate, instead of pi-accepting CO-bridged ligand as observed in [Fe] hydrogenases. Additionally, in a compound of unusual composition ([Na.(5)/(2)H(2)O][(CN)(CO)(2)Fe(mu-SEt)(3)Fe(CO)(2)(CN)])(n)((1)/(2)O(Et)(2))(n) (3), the Na(+) cations and H(2)O molecules combining with dinuclear [(CN)(CO)(2)Fe(mu-SEt)(3)Fe(CO)(2)(CN)](-) anions create a polymeric framework wherein two CN(-) ligands are coordinated via CN(-)-Na(+)/CN(-)-(Na(+))(2) linkages, respectively. 相似文献
992.
993.
Pal R Yang M Lin R Johnson BN Srivastava N Razzacki SZ Chomistek KJ Heldsinger DC Haque RM Ugaz VM Thwar PK Chen Z Alfano K Yim MB Krishnan M Fuller AO Larson RG Burke DT Burns MA 《Lab on a chip》2005,5(10):1024-1032
An integrated microfluidic device capable of performing a variety of genetic assays has been developed as a step towards building systems for widespread dissemination. The device integrates fluidic and thermal components such as heaters, temperature sensors, and addressable valves to control two nanoliter reactors in series followed by an electrophoretic separation. This combination of components is suitable for a variety of genetic analyses. As an example, we have successfully identified sequence-specific hemagglutinin A subtype for the A/LA/1/87 strain of influenza virus. The device uses a compact design and mass production technologies, making it an attractive platform for a variety of widely disseminated applications. 相似文献
994.
An enhancive synthesis of (±)-1β, 11-diol-4-en-eudesmol,starting from 2-chloroacrylonitrile, is described. The effect oftemperature on the Diels-Alder reaction of 2-chloroacrylonitrilewith 2-methylfuran and the condition of cationic cyclization ofdiene were discussed in detail. 相似文献
995.
Song C Wang D Gu G Lin Y Yang J Chen L Fu X Hu Z 《Journal of colloid and interface science》2004,272(2):340-344
Silver-coated poly(methyl acrylic acid) (PSA) core-shell colloid particles were prepared by an in situ chemical reduction method. Crystalline silver/titania composite hollow spheres were obtained by coating the as-prepared PSA/silver particles with an amorphous titania layer and subsequently calcining in Ar atmosphere. SEM and TEM investigation indicated that the size of the as-prepared PSA/silver and PSA/silver/TiO(2) core-shell particles and silver/titania composite hollow particles was fairly uniform and the wall thickness of the hollow spheres was in the range of 40-80 nm. UV-vis absorption spectra were recorded to investigate their optical properties. 相似文献
996.
Xiaofeng Zhang Shen Lin Xinqing Chen Jiebo Chen Liuyi Yang Minghong Luo 《Frontiers of Chemistry in China》2007,2(4):419-421
Mesoporous aluminophosphate was prepared by using G4.0 poly(amido amine)dendrimer as a template and characterized by Fourier
transform infrared spectrometer (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and N2 adsorption/desorption methods. Results show that the title compound exhibits a typical mesoporous structure with the average
pore size from 5 to 8 nm. The formation mechanism of the nanoporous structure using dendrimer as a template was also discussed.
__________
Translated from Journal of Fujian Normal University (Natural Science Edition), 2007, 23(2): 67–70 [译自: 福建师范大学学报 (自然科学版)] 相似文献
997.
三效催化剂作用下的NO+CO催化反应机理 总被引:1,自引:0,他引:1
NO与CO在Pt/Rh/Pd及载体组成的三效催化剂上的氧化还原应用是控制汽车尾气对空气污染的一个关键反应,这一反应随着近年来对环境保护的日益重视而成为国内外研究的热点,本文主要综述了NO及CO在Pt,Rh,Pd上的吸附及反应机理的实验及理论研究现状,总结得出:在三效催化剂对NO CO的催化反应中,Pt,Pd对CO的催化氧化起主要作用,而Rh对NO的解离有很好的活化作用。 相似文献
998.
999.
1000.
壳聚糖季铵盐的合成及结构表征 总被引:39,自引:4,他引:39
用异相法合成了水溶性壳聚糖季铵盐衍生物,并用红外光谱及核磁共振谱进行结构表征。结果表明:在中性反应条件下,壳聚糖分子的季铵盐衍生化反应主要发生于亲该中心C2位的氨基上,所合成的壳聚糖季铵盐衍生物可直接溶解于水。其水溶液可以任意比例与乙醇、丙二醇、甘油等混溶。 相似文献