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141.
<正>有机锡化合物因具有抗癌活性和杀菌、杀螨作用,以及结构特点多变、反应性丰富,近年来引起了人们的高度关注,已合成出许多结构新颖和性能特殊的有机锡化合物[1-4]。研究发现,有机锡化合物中,中心锡原子的配位形式取决于与锡原子直接相连的  相似文献   
142.
The tri(n-butyl)tin 3-amino-2-pyrazine formic ester polymer [n-Bu3Sn(O2CC4H2N2NH2-o)]n has been synthesized and characterized by IR, 1H NMR spectra and elemental analysis. Its crystal structure has been determined by X-ray diffraction. The crystal belongs to monoclinic space group P21/c with a=1.057 7(2) nm, b=1.083 6(2) nm, c=1.905 2(4) nm, β=100.604(3)°, Z=4, V=2.146 3(8) nm3, Dc=1.325 Mg·m-3, μ(Mo Kα)=1.202 mm-1, F(000)=880, R1=0.039 3, wR2=0.113 3. In the complex, tin atoms are five-coordinated distorted trigonal bipyramid configuration. Through the intermolecular N-H…N hydrogen bonds to form network structure with a “double bridge”. The result of analysis shows that the Sn(Ⅳ)/Sn(Ⅱ) electron transfer in electrode reaction is irreversible. CCDC: 779860.  相似文献   
143.
The title compound,[Ag(L)]·H2O,1,where HL=4-(isonicotinamido)benzoic acid,was synthesized in methanol solution and its crystal structure was determined by X-ray diffraction analysis.The crystal is of monoclinic.space group P21/c with a=0.571 8(8)nm,b=1.357 2(18)nm,c=1.5580(2)nm,β=91.090(2)°,V=1.2090(3)nm3,Z=4,Dc=2.009 g·cm-3,F(000)=722,Rint=0.042 9,R=0.027 1,wR=0.055 6.In complex 1,the Ag atoms are linearly coordinated by one O atom and one N atom of two ligand molecules.Each I- ligand in turn uses its one carboxylate group and one pyridinyl groups to connect two metal centers,then the one-dimensional (1D) chains is formed.On the other hand,the 1D chains are further connected by O1W-H1WB…O2 hydrogen bonds and Ag-O weak interactions to give a two-dimensional (2D) layer,finally,the 2D net extents to three-dimensional (3D) supramolecular framework by O1W-H1WB…O1 as well as N2-H2…O2 interactions.CCDC:762259.  相似文献   
144.
以环氧氯丙烷作交联剂合成了一种非水溶性的β-环糊精聚合物,用该聚合物作固定相研制成了柱效高、热稳定性好的玻璃SCOT柱,对丁醇异构体,二取代苯异构体,龙脑、异龙脑顺反异构体和旋光异构体进行了分离,取得令人满意的效果  相似文献   
145.
罗李平 《大学数学》2008,24(1):25-28
研究一类具有连续分布滞量的偶数阶非线性中立型泛函微分方程解的振动性,得到了该类方程的若干新的振动准则.所得结果推广和包含了已知的一些结论.  相似文献   
146.
配位聚合物由于在催化材料、磁性材料和光学材料等领域中具有广泛的应用价值,近年来已引起人们的极大关注。含氮、含氧桥联配体是合成具有  相似文献   
147.
The title complex has been synthesized by using terephthalic acid (PTA), 1,10-phenanthroline (phen) and copper monohydrate. It crystallizes in monoclinic space group C2/c with a=2.959 0(2) nm, b=1.466 4(10) nm, c=1.764 3(12) nm, β=105.593(11)°, V=7.372(9) nm3, Dc=1.489 g·cm-3, Z=8, F(000)=3 416, R1=0.043 6, wR2= 0.151 9. The crystal structure shows that the copper atom is coordinated with four nitrogen atoms from two phens and one oxygen atom from one terephthalic acid, forming a distorted square-pyramid coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 277047.  相似文献   
148.
A complex {[Co(4,4′-bipy)(H2O)4]·(α-Furacrylic acid)2·(H2O)}n with α-furacrylic acid, 4,4′-bipy and cobaltous chloride hexahydrate has been synthesized by means of hydrothermal way and characterized. Crystal data for this complex: monoclinic, space group P21/c, a=1.147 0(2) nm, b=1.099 9(2) nm, c=1.111 1(2) nm, β=97.829(3)°, V=1.388 7(5) nm3, Dc=1.429 g·cm-3, Z=2, μ(Mo Kα)=0.682 mm-1, F(000)=622, S=1.025, R1=0.035 8, wR2=0.086 1. The crystal structure shows that the cobalt(Ⅱ) ion is coordinated with two nitrogen atoms of two 4,4′-bipy molecules and four oxygen atoms from four water molecules, respectively, giving a distorted octahedral coordination geometry. Adjacent cobalt(Ⅱ) ions are bridged by 4,4′-bipy groups, resulting in a 1D chain structure. The adjacent Co(Ⅱ)-Co(Ⅱ) distance is 1.147 0 nm. The cobalt(Ⅱ) ion isn′ t coordinated with α-Furacrylic acid. The complex molecules form 2D structure through hydrogen bonds. The cyclic voltametric behavior of the complex was also investigated. CCDC: 648243.  相似文献   
149.
A manganese coordination polymer [Mn(3,5-Me2PhCO2)2(phen)]n(phen=1,10-phenanthroline) has been synthesized by hydrothermal methods. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a=0.770 3(4) nm, b=1.145 2(6) nm, c=1.537 0(9) nm, α=78.182(9)°, β=77.170(9)°, γ=89.784(9)°, V=1.292 8(12) nm3, Z=2, Mr=533.47, Dc=1.370 g·cm-3, μ=0.549 mm-1, F(000)=554, Rint=0.043 4, R=0.060 8 ,wR=0.148 4. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from phen and four oxygen atoms from four 3,5-dimethylbenzolate molecules, completing an octahedral geometry. And the title complex forms one-dimensional chain structure through bridging 3,5-dimethylbenzolate molecules. CCDC: 642920.  相似文献   
150.
一类非对称单调变分不等式的交替方向法   总被引:1,自引:0,他引:1  
对一类非对称变分不等式问题提出了交替方向法。推广了交替方向仅适用于等式约束或不等约束的情形,得出了迭代序列的一些性质及收敛性.  相似文献   
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