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981.
合成了三(三苯基氧膦)合硝酸镧络合物, 经鉴定确定络合物化学式为La(NO_3)_3·3ph_3PO·C_2H_5OH·CHCl_3。其中C_2H_5OH和CHCl_3为溶剂化分子。经X射线单晶衍射, 测定了该络合物属单斜晶系P2_1/n空间群, 晶体学参数如下a=1.3111(5) nm Z=4b=2.5075(10) nm F(000)=2687.65c=1.8725(6) nm μ吸收系数=9.83(cm~(-1))β=98.53(3)° d计算=1.45 gcm~(-3)V=6.088 nm d实验=1.43 gcm~(-3)La与9个氧直接配位, 其中六个氧来自三个双卤配位硝酸根, 另三个氧分别由三个苯基氧膦上的膦酰基所提供。La-O平均键长0.2549 nm。 相似文献
982.
河豚鱼脂肪酸的气相色谱—质谱分析 总被引:10,自引:0,他引:10
采用GC/MS技术对2种河豚鱼(黄鳍、红鳍)脂肪提取物中的脂肪酸进行定性定量分析,共鉴别出24种脂肪酸。多不饱和脂肪酸尤其是二十二碳六烯酸(DHA)的含量很高,在黄猪中相对含量达32.32%,在红鳍中达24.11%。检出了在其它海产品中较少发现的15-二十四烯酸(神经酸),是人体生长发育不可缺少的一种脂肪酸。对鱼肉脂肪提取方法及不同极性毛细管柱分离情况进行了讨论。 相似文献
983.
The reactions of 1,4-bis(phenylthio)butane (L) with Ag(I) salts in varied conditions (varying the solvents, metal-to-ligand ratios, and counteranions) lead to the formation of four new two-dimensional (2D) coordination polymers with different network structures: [Ag(2)L(3)(ClO(4))(2)](infinity) 1, [Ag(2)L(3)(ClO(4))(2) x CH(3)OH](infinity) 2, [[AgL(2)](ClO(4))](infinity) 3, and [AgLNO(3)](infinity) 4. All the structures were established by single-crystal X-ray diffraction analysis. Crystal data for 1: triclinic, P-1, a = 11.0253(9) A, b = 11.3455(9) A, c = 11.5231(9) A, alpha = 93.931(2) degrees, beta = 92.689(2) degrees, gamma = 112.9810(10) degrees, Z = 2. 2: triclinic, P-1, a = 11.9147(13) A, b = 16.1534(17) A, c = 16.2259(17) A, alpha = 74.977(2) degrees, beta = 69.030(2) degrees, gamma = 69.986(2) degrees, Z = 2. 3: triclinic, P-1, a = 12.1617(9) A, b = 12.5054(10) A, c = 13.1547(10) A, alpha = 64.3370(10) degrees, beta =85.938 (2) degrees, gamma = 69.3010(10) degrees, Z = 2. 4: monoclinic, P2(1)/c, a = 5.4032(17) A, b = 16.974(6) A, c = 19.489(6) A, beta = 94.234(6) degrees, Z = 4. In all four complexes, each Ag(I) center has a tetracoordination geometry, and the 2D networks consist of fused large macrometallacyclic ring systems. The "hexagonal" 42-membered rings, Ag(6)L(6), observed in 1 and 2 are nearly identical, which could be considered as unique examples of self-sustaining noninterpenetrated frameworks formed with flexible ligands. The repeating rectangular 28-membered macrometallacycle, Ag(4)L(4), is the basis for the network of 3, in which the perchlorate anions occupy the voids to prevent the ring from collapsing. In 4, columns of the fused rectangular 22-membered rings, Ag(4)L(2)(NO(3))(2), are cross-linked through the L ligands to form a unique 2D network consisting of two types of 22-membered repeating units. 相似文献
984.
985.
The photoluminescence of Co-Al-layered double hydroxide 总被引:1,自引:0,他引:1
Shuai Sun Wan Guo Hou 《中国化学快报》2007,18(11):1371-1373
We report a new optical behaviour of pure Co-Al-layered double hydroxide (LDH).It was found that the Co-Al-LDH sample could emit fluorescence without any fluorescent substances intercalated.Its excitation spectrum shows a maximum peak near the wavelength 370nm,the maximum emission peak appears at 430 nm and the photoluminescence colour of the Co-Al-LDH sample is blue.This new optical property will be expected to extend the potential applications of LDHs in optical materials field. 相似文献
986.
Peiguang Zhou Harry L. Frisch H. Ghiradella 《Journal of polymer science. Part A, Polymer chemistry》1992,30(5):835-843
Simultaneous interpenetrating polymer networks (IPN's), pseudo IPN's, and liner blends of aliphatic poly(carbonate-urethane) (PCU) and polyvinyl pyridine (PVP) have been prepared and characterized by DSC, DMA, and TEM. The full IPN's of PCU and PVP had a single phase morphology only above 50 wt % PCU, as determined by both DSC and DMA and confirmed by transmission electron microscopy (TEM). However, in both pseudo IPN's of PCU and PVP and in their linear blends there exist multiple glass transitions and melting points seen by DSC and DMA indicating phase incompatibility. The full IPN's exhibited superior ultimate mechanical properties and solvent resistance as compared to the pseudo IPN's, liner blends, and the pure crosslinked PCU and PVP networks. 相似文献
987.
988.
We consider some wide class of general systems of Korteweg-de Vries equations which contain nonlinear terms with derivatives of higher order, we have proved the existence of generalized solution for this system and the asymptotic behavior ast and blow up property of the solution are discussed. 相似文献
989.
羧基丙烯酸酯涂料合成及其防雾性能研究 总被引:3,自引:2,他引:3
采用种子乳液聚合法合成了一种互穿网络型羧基丙烯酸酯类聚物乳液,研究了加料方式对羧基分布的影响,结果表明丙烯酸加入到核单体中有利于羧基分布在乳胶粒表面。在体系中引入离子键交联结构提高了乳液涂料的硬度和耐水性能,离子键交联PILN型涂料具有优良的防雾性能。 相似文献
990.
A new polysiloxane with pendent sugar units was prepared by a two-step method: the preparation of the polysiloxane with amino groups on the side chain and then the copolysiloxane reacted with glucosyl isothiocyanate. All polymers were characterized by FT-IR 1H-NMR, 1H-1H-COSY, 13C-NMR, and DEPT respectively. In the same time, Platinum oxide was found to be a versatile and powerful hydrosilation catalyst in the hydrosilylation reaction of aminotrimethylenepolysiloxanes with heptamethylcyclotetrasiloxane (D4H). 相似文献