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A novel bimetallic porphyrin complex salt, {[MnTPP(CH3OH)2]3Fe(CN)6}·13H2O (TPP = tetraphenylporphyrin), has been synthesized and structurally characterized by X-ray diffraction analysis. The crystal is of trigonal, space group R-3 with a = b = 31.0618(10), c = 11.8366(8) (A), Z = 3, V = 9890.3(8) (A)3, C144H134FeMn3N18O19, Mr = 2641.36, Dc = 1.330 g/cm3, μ(MoΚα) = 0.463 mm-1, F(000) = 4131, R = 0.0525 and wR = 0.1382 for 3045 observed reflections (I > 2((I)). The title complex is composed of one [Fe(CN)6]3- anion, three [MnTPP(CH3OH)2] cations and thirteen water molecules, which are connected by multiform hydrogen bonds leading to a 3D supramolecular network structure. 相似文献
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A substituted polyacetylene bearing a furan ring, poly(2-propynyl 2-furoate) (PPF), was synthesized for the first time with palladium acetylide complex catalysts in CHCl3 at 60℃ to give a soluble and stable polymer with a yield of ca.75%. Some features for polymerization of 2-propynyl 2-furoate are described and discussed. The resulting polymer was characterized by IR, GPC and ^1H-NMR analysis. 相似文献
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ErS+-doped phosphor-tellurite glass for broadband short-length Er3+-doped fiber amplifier (EDFA) is fabricated and characterized. The differential value (△T) of onset crystalline temperature (Tx) and glass transition temperature (Ts) is 206°C. 相似文献
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纯正半群上的同余扩张(一) 总被引:1,自引:1,他引:0
刻划半群上的同余及其扩张是半群的代数理论中的一个非常重要的课题.本文讨论了带上的同余的正规性和不变性以及在其Hall半群上的扩张,从同余扩张的角度刻划了带上的同余的性质,给出了扩张的极大、极小同余的描述. 相似文献
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Grafting polymer glycols onto nano-silica surface through one-step procedure was investigated. The major characteristic of this procedure is that all the materials and reagents (silica, PEG, TDI, DBTDL, solvent) required for grafting were added simultaneously into the reaction vessel. TDI and DBTDL were used as coupling agent and catalyst, respectively.The products were characterized by FTIR, TGA, elemental analyses and TEM, giving evidence for successful grafting of PEG. Possible mechanism of this grafting was studied and two grafting processes were proposed. The process through which the grafting proceeds depends on the reaction temperature. Effect of molecular weight of PEG on grafting was also investigated. 相似文献
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A model compound for the active sites of Fe-only hydrogenases,[Fe2(SCH2)2N(3-PhCF3)(CO)6]2,has been synthesized and structurally characterized by single-crystal X-ray diffraction.It crystallizes in tetragonal,space group P43,with a = 12.6324(3),b = 12.6324(3),c=24.0453(12) (A),V = 3837.1(2) (A)3,Z = 4,Fe4S4N2C30O12F6H16,Mr= 1062.09,Dc= 1.839 g/cm3,μ(MoKa) = 1.791 mm-1,F(000) = 2112,T= 293(2) K,Flack = 0.034(9),R= 0.0282 and wR =0.0685 for 8148 observed reflections with I > 2σ(I).In the title compound,each Fe1 atom is coordinated by three terminal carbonyl C atoms (Fe-C:1.783(3)~ 1.816(3)(A)),two bridging S atoms (Fe-S:2.2609(7)~2.2757(8)(A)) and another Fe atom (Fe-Fe 2.5011(5) (A)),adopting a distorted octahedral geometry with trans angles ranging from 152.45( 11 ) to 157.77(10)°. 相似文献
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LI Xue-Mei ZENG Cheng-Chu JIAO Zi-Guo YAN Hong ZHONG Ru-Gang 《结构化学》2007,26(6):669-673
The title compound 7-acetamido-5-chloro-8-(p-methyloxybenzenesulfonyloxy)-2- styrylquinoline 4 (C26H21ClN2O5S, Mr = 508.96) has been synthesized and characterized by 1H- NMR, IR, ESI-MS and single-crystal X-ray diffraction techniques. The crystal belongs to orthorhombic, space group Pca21, with a = 7.920(3), b = 10.672(5), c = 28.008(12) , V = 2367.3(17) 3, Z = 4, Dc = 1.425 g/cm3, μ = 0.290 mm-1, F(000) = 1056, R = 0.0323 and wR = 0.0692 for 3895 unique reflections with 3127 observed ones (I > 2σ(I)). X-ray analysis reveals that the styrylquinoline subunit adopts a coplanar conformation, where the benzene ring and quinoline are in trans configuration. 相似文献