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991.
A new fluorinated polystyrene bearing a p-sulbstiuted perfluoro[1-(2-fluorosulfonylethoxy)]ethyl group was synthesized via one-electron oxidation of polystyrene by perfluoro[2-(2-fluorosulfonylethoxy)]propionyl peroxide at different peroxide to polystyrene molar ratios.The yield of perfluoroalkylation decreases with the increase of the reactant molar ratio.The modified polymer has been characterized by various techniques:the ring pefluoro[1-(2-fluorosulfonylethoxy)]ethylation has been proved by FT-IR and ^19FNMR;the X-ray photoelectron spectra(XPS) show the maximum binding energy of F18,O18,C18(two kinds of carbon atoms,namely C-H and C-F)and S2p,respectively; desulfonylation of the fluorinated polystyrene appearing at 217℃ has been found by its thermogravimetric analysis (TGA).The determinations of contact angle,refractive index and glass transition temperature of the modified polymer have disclosed that when the contact angle increases with the increase of the molar ratio,the refractive index and glass transition temperature decrease.The polydispersity values indicate that the degradation of the polymer chains did not occur during the reaction. 相似文献
992.
Synthesis and Structural Characterization of [Mn(sapn)(H2O)2]Br 总被引:1,自引:0,他引:1
1 INTRODUCTION Many of the recent advances in the coordination chemistry of manganese have been driven by the involvement of the manganese in several biological redox-active systems[1,2], of which the most important is the oxygen-evolving complex (EOC) of photosystem II (PS II) in green plants [3]. Since the preparations and structural characterizations of the complexes containing N,O-donor ligands have been studied extensively as simple active-site models for the photosystem II[4,5]… 相似文献
993.
994.
YingChunLIU GuoZhenXIAO QiWANG 《中国化学快报》2004,15(7):879-882
The diffusivity and viscosity of water confined in micropores were studied by molecular dynamics simulations. The effects of pore width and density were analyzed at pore widths from 0.9 to 2.6nm. The diffusivity in micropores is lower than that of the bulk, and it decreases as pore width decreases and as density increases. But the viscosity in micropores is much larger than that of the bulk, and it increases as pore width decreases and as density increases. The diffusivity in channel parallel direction is obviously larger than that in channel perpendicular directions. 相似文献
995.
稀土氨基酸固体络合物的合成及结构分析进展 总被引:16,自引:2,他引:16
本文综述了稀土氨基酸络合物的合成,以及应用红外、核磁、X-射线衍射、热分析等方法进行结构分析研究的进展情况。 相似文献
996.
反-1,2-双[2-(5-取代苯基恶唑基)]环丙烷的合成与光性能的研究 总被引:2,自引:0,他引:2
合成了8个反 -1,2-双[2-(5-取代苯基恶唑基)]环丙烷和2个1,2-双[2-取代苯基恶唑基)]乙烷,其中9个为新化合物.讨论了化合物的结构与其电子光谱及荧光量子产率间的关系.发现恶唑环与三元环间存在一定程度的共轭,并解释了上述化合物荧光量子产率较低的现象. 相似文献
997.
γ-[SiW10O36]8-夹心型稀土元素单取代多酸化合物的合成与表征 总被引:2,自引:0,他引:2
利用缺位填充法合成了12个γ-[SiW10O36]8-夹心型稀土元素单取代多酸化合物K13[Ln(SiW10O36)2]·nH2O(Ln=La3+,Ce3+,Pr3+,Nd3+,Sm3+,Eu3+,Gd3+,Tb3+,Dy3+,Ho3+,Er3+,Yb3+).通过元素分析确定其组成,由红外光谱、紫外-可见吸收光谱、循环伏安及室温磁化率测定结果确认稀土离子与γ-[SiW10O36]8-相配位;183WNMR及荧光光谱结果则表明,稀土离子处于2个γ-[SiW10O36]8-构成的八配位环境中,标题化合物具有夹心型D2d对称性结构. 相似文献
998.
ZHANG Gai LIANG Yong-Qing ZHANG Rong-Lan ZHANG Wei-Hai ZHAO Jian-She GUO Zhi-An 《结构化学》2005,24(7):783-789
A new quinazolinone compound 2,3-dihydro-2-(2-hydroxyphenyl)-3-phenylquinazolin-4(IH)-one 3 ([C2oH16O2N2]-C2H5OH, Mr = 362.42) and compound 2-(2-hydroxybenzylidene-amino)-N-phenyl-benzamide 2 (C2oH16O2N2, Mr = 316.34) were prepared from a precursor of 2-amino-N-phenyl-benzamide 1 (C13H12ON2, Mr = 212.25). Compound 3 was characterized by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic,space group Pbca with a = 1.2889(11), b = 1.6170(14), c = 1.7729(15) nm, V= 3.695(6) nm^3, Z= 8, F(000) = 1536, Mr = 362.42, Dc = 1.303 g/cm^3, μ(MoKa) = 0.087 mm^-1, R = 0.0447 and wR= 0.0879. The crystal structure analysis indicates that the title compound has a two-dimensional network structure formed by hydrogen bonds and electrostatic interactions. 相似文献
999.
A series of Mo-impregnated Hβ samples, with MoO3 loading in Hβ zeolite in the mass fraction range of 0. 5%-6.0%, were studied by means of XRD and IR in order to characterize their structures. Mo/Hβ sampies‘ crystallinity almost linearly decreases with increasing the amount of MoO3 loaded, The IR spectra and XRD patterns suggest that the progressive destabilization of the Hβ zeolite structure is caused by increasing Mo loading in (MoO3 Hβ zeolite). During the calcination, Al2(MoO4)3 formed from the dealumination of Hβ zeolite, causes the substantially partial breakdown of the zeolite framework when the Mo loading in MoO3 Hβ is relatively high. 相似文献
1000.
Chun Xia Tan Ruo Fei Feng Xiao Xia Peng 《中国化学快报》2007,18(5):505-508
By the condensation of 2,6-bis(4-amino-5-mercapto-[1,2,4]-triazoles-2)pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis(6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl)pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity. 相似文献