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61.
Using the ligand pyridazine-3,6-dicarboxylate (H2pzdc), a coordination polymer [Cd2(pzdc)2(H2O)4] was synthesized and characterized by elemental analysis, thermal analysis, IR and single-crystal X-ray diffraction. The complex crystallizes in the tetragonal system with space group I41/a. The crystallographic data are: a=1.470 6(4) nm, c=1.489 8(6) nm, V=3.222 0(19) nm3, Z=16, μ=2.725 mm-1, Dc=2.594 g·cm-3, R1=0.017 8, wR2=0.044 6. In the complex, the cadmium(Ⅱ) ions with the eight-coordinated dodecahedral geometry are linked by the pzdc ligands to generate one-dimensional chains, which are associated into the three-dimensional architecture via O-H…O hydrogen bonding. CCDC: 658853. 相似文献
62.
63.
α—甲基苯乙烯离子聚合体分子量分布 总被引:1,自引:0,他引:1
聚α-甲基苯乙烯-丁二烯-α-甲基苯乙烯嵌段共聚物是一种性能优异的热塑性弹性体。常温下,α-甲基苯乙烯的聚合是在极性添加剂存在下进行的,添加剂的种类,用量及聚合温度不仅影响聚合动力学,尚且影响聚合物分子量及其分布,控制α-甲基苯乙烯聚合速率、 相似文献
64.
JianXinPU JingFengZHAO XiaoDongYANG ShuangXiMEI HongBinZHANG LiangLI 《中国化学快报》2004,15(12):1454-1456
A new sesquiterpene lactone, Ainsliaolide A, was isolated from Ainsliaea bonatii. The structure was determined on the basis of spectral data. 相似文献
65.
66.
The utility of ring-fused 2,3-oxazolidinone derivatives of 2-amino-2-deoxy-thioglycosides in the synthesis of glycopeptide intermediates and building blocks for the synthesis of heparan sulfate oligosaccharides is reported. These unique ring-fused monosaccharides afford a novel and efficient route to alpha-O-linked 2-amino-2-deoxy amino acid derivatives and heparan sulfate oligosaccharide intermediates. 相似文献
67.
AB5型球形合金粉的表面处理研究 总被引:2,自引:0,他引:2
由雾化(Gas-atomization)技术制备的AB5型球形合金粉,作为镍氢电池负极材料具有很多优点:粉粒呈球状便于在多孔基片内装填;耐压耐磨性好;抗碱能力强且不易解胶.但它的电化学初活性差,难于活化.有碍电池中的应用.采用适宜的氧化剂(铜盐水溶液)处理,使球粒表面形成一个富铜、富镍亚层,显著地改善了合金粉的电化学活性.经处理的MlNi3.8CO0.5Mn0.3Al0.4球形合金粉,仅3次充放电循环其放电量便可达到240mA·h·g-1;而未经处理的同一合金粉即便经6次充放电循环其放电量也只有103mA·h·g-1. 相似文献
68.
69.
Yong Ding Baochun Ma Qiang Gao Guixian Li Liang Yan Jishuan Suo 《Journal of molecular catalysis. A, Chemical》2005,230(1-2):121-128
The epoxidation of cyclopentene with hydrogen peroxide catalyzed by 12-heteropolyacids of molybdenum and tungsten (H3PMo12−nWnO40, n = 1–11), 12-tungstophosphoric acid and 12-molybdophosphoric acid combined with cetylpyridinium bromide as a phase transfer reagent was carried out in acetonitrile. Among 13 heteropolyacids investigated, catalyst of H3PMo6W6O40 showed the highest activity, giving a conversion of 60% and a selectivity of 95% in the epoxidation of cyclopentene. The fresh catalysts and the catalysts under reaction condition were characterized by UV–vis, FT-IR and 31P NMR spectroscopy, which has revealed that all of the molybdotungstophosphoric acids were degraded in the presence of hydrogen peroxide to form a considerable amount of phosphorus-containing species. The active species resulted from H3PMo6W6O40 are new kinds of phosphorus-containing species, which is different from {PO4[WO(O2)2]4}3−. 相似文献
70.
The first examples of mononuclear, structurally characterized triarylphosphine complexes of zirconium and hafnium are reported. The metathetical reactions of MCl4(THF)2 (M = Zr, Hf) with [iPrNP]Li(THF)2 ([iPrNP]- = N-(2-(diphenylphosphino)phenyl)-2,6-diisopropylanilide) or [MeNP]Li(THF)2 ([MeNP]- = N-(2-(diphenylphosphino)phenyl)-2,6-dimethylanilide) in toluene at -35 degrees C produced the corresponding [iPrNP]MCl3(THF) and [MeNP]2MCl2, respectively, in high yield. In contrast, attempts to prepare [MeNP]MCl3(THF) and [iPrNP]2MCl2 led to the concomitant formation of mono- and bis-ligated complexes, from which purification proved rather ineffective. The solution and solid-state structures of [iPrNP]MCl3(THF) and [MeNP]2MCl2 were studied by multinuclear NMR spectroscopy and X-ray crystallography. The geometry of these six-coordinate complexes is best described as a distorted octahedron in which the chloride ligands in [iPrNP]MCl3(THF) adopt a virtually meridional coordination mode whereas those in [MeNP]2MCl2 are trans to each other. 相似文献