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41.
Ju Tao LIU Xiao Hong WANG Jing Fu LIU Faculty of Chemistry Northeast Normal University Changchun 《中国化学快报》2004,15(7):859-862
A novel vanadate decamer, involving all vanadium atoms present in +5 oxidation and one formhydroxamic acid dimer cation readical, has been synthesized. The single-crystal X-ray diffraction shows that the orange crystal is formed in the triclinic system, space group Pi, a = 8. 4960 (17), b = 10.447 (2), c = 11.299 (2) A, α= 68. 82 (3)°,β= 87.35 (3)°, γ = 66.97(3)°. V = 855. 3(3) A3, Z = 8, R1 = 0. 0857, wR2=0. 2551. X-ray crystallographic and packing in superlattice studies showed that the crystal structure was constructed by electrostatic attraction of O-H…O hydrogen bonds between formhydroxamic acid dimer cation and decavanadate polyanion. Formhydroxamic acid dimer is got through controlling the condition of the reaction using formhydroxamic acid. 相似文献
42.
1 INTRODUCTION In 1984, thiolate ligand was successfully introduced into molybdenum carbonyl compound by the reaction of Mo(CO)6 with [Et4N]SR( R = C6H5, But) in a moderate condition[1]. From then on, a series of dinuclear molybdenum(0) carbonyl thiolate compounds have been synthesized and characterized by using a variety of thiolate ligands in our research group. It was found that a planar Mo2S2 unit is in the compound [Et4N]2[Mo2(CO)8(SC6H4-CH_3-p)2][2] (2) and a "butterfly" t… 相似文献
43.
N,N′—1,2—丙水杨酰胺合铜(Ⅱ)酸根的双核Cu(Ⅱ)配合物的合成与磁性 总被引:1,自引:0,他引:1
合成了一类新的金属配合物[Cu(sampn)CuL](sampn^4-:N,N′-1,2-丙水杨酰胺根离子;L:2,2-联吡啶或1,10-菲绕啉),经元素分析、IR、电子光谱等手段推定配合物具有酚氧桥结构,Cu(Ⅱ)离子和配位环境为畸变四方构型,测定了配合物的变温磁化率,其数值用量二乘法与修正的Bleaney-Bowers方程拟合,从中得到较大的θ值,表明双核分子间有较大的分子间相互作用。 相似文献
44.
A vinyl monomer having an electron-donating moiety, p-(N,N-dimethylamino)styrenc (DMAS),was synthesized. It was combined with benzoyl peroxide (BPO) to form a redox initiation system to initiatethe polymerization of methyl methacrylate (MMA). UV spectra measurements show that DMAS enters thePMMA chain as well. Both DMAS and its polymer P(DMAS) display strong fluorescence, and thefluorescence can be quenched by electron-deficient compounds such as methacrylonitrile, fumaronitrile andmethyl methacrylate etc. Moreover, DMAS can also form charge transfer complex (CTC) with strongelectron acceptors such as tetracyanoethylene (TCNE). The difference between the photochemical propertiesof DMAS and P(DMAS) were explained in terms of molecular structure change and polymer conformationeffect in solution. In addition, the CTC and exciplex formation of DMAS or P(DMAS) with C_(60) were alsostudied. 相似文献
45.
N-甲基吡咯烷酮、α-吡咯烷酮合成物系气相色谱分析 总被引:1,自引:0,他引:1
This paper describes a GC analytical method in the synthes is of N-methyl pyrrolidone of a-pyrrolidone.This procedure was performed with a column packed with 6%OV-17/silanized 101 support and FID detec-tor. Calibration factors and detection conditions are given,The coefficients of variation of NMP and a-P were0.6%and 0.5%respectively. The relative errors of all the components were not more than±3.0%,Thequantitative analysis is fast,simple and accurate. 相似文献
46.
疏水缔合型增稠剂聚(丙烯酰胺-丙烯酸高级酯)的合成及增稠性能研究 总被引:5,自引:0,他引:5
采用沉淀聚合法合成了聚(丙烯酰胺-丙烯酸十四酯),聚(丙烯酰胺-丙烯酸十六酯)和聚(丙烯酰胺-丙烯酸十八酯),重点讨论了共聚物中疏水基团数量及疏水基团链长对增稠性能的影响。采用凯达尔定氮法和动态热分析(DMTA)测定了共聚物的组成及玻璃化温度。 相似文献
47.
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49.
高效液相色谱法测定橡胶促进剂TBBS 总被引:3,自引:0,他引:3
采用反相高效液相色谱法(HPLC)测定了橡胶促进剂N-叔丁基-2-苯并噻唑次磺酰胺(TBBS)的纯度,标准偏差小于0.3。 相似文献
50.
Oneofthemostimportantaimsofphotochemistryisthedesignandconstructionofmoleculardevicesforener gyconversionandinformationprocessing .Thephotoactivemoleculardevicesarebasedonthephotoinducedelectrontransferbetweendonor acceptortypeorganiccompoundsandaccept… 相似文献