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91.
The paper reported the synthetic procedure and character of Copper(Ⅱ) binuclear coordination compound of 1,4-bis-(1′-phenyl-3′-methyl-5′-pyrazolone-4′)-1,4-butanedione. The non-isothermal kinetic of the thermal decomposition of the complex has been studied from the TG-DTG curves by means of the Achar et al and Coats-Redfern methods. The electrochemical characterization of the complex were studied by means of powder microelectrodes technique.  相似文献   
92.
A novel coordination polymer of [Sr2(4-CPOA)2(H2O)5]n (where 4-CPOA2- is 4-carboxylphenoxyacetate) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex belongs to monoclinic system with space group C2/c, a=2.563 9(5) nm, b=1.162 7(2) nm, c=0.742 96(15) nm, β=99.64(3)°. V=2.183 5(7) nm3, Z=4, Mr=653.60, Dc=1.988 g·cm-3, R=0.027 8, wR=0.058 1. The strontium atom has a bicapped triangular prismatic coordination geometry, involving four oxoacetate oxygen atoms, one ether oxygen atom from different 4-CPOA2- ligands and three water molecules. The strontium(Ⅱ) ions are linked by 4-CPOA2- ligands and water molecules to form a 3D network structure. CCDC: 223313.  相似文献   
93.
Dinuclear silver (I) six‐membered ring complex [Ag2 (bta)2 ‐(hmbta)2] (ClO4)2 (3) has been synthesized by the reaction of benzotriazole (bta) (1) and 1‐hydroxymethyl benzotriazole (hmbta) (2) with Ag (CH3CN)4ClO4. The structures of compound 2 and Complex 3 have been studied by single crystal X‐ray diffraction analysis. The change of luminescent intensity of 1, 2 and 3 was reported. Compound 2 crystallizes in the monoclinic system with space group P2 (1)/c, a = 0.7655 (10) nm, b = 1.0126 (14) nm, c =0.9502 (13) nm, β = 95.07 (2)°, V = 0.7337 (17) nm3 and Z = 4. Complex 3 crystallizes in the triclinic system with space group P1, a = 0.73611 (18) nm, b = 0.9152 (2) nm, c = 1.2277 (3) nm, β = 87.170 (5)°, V = 0.8221 (3) nm3 and Z = 1. The main structural feature of complex 3 is a symmetric dinuclear six‐membered ring formed by two silver (I) atoms and four N‐atoms from two benzotriazoles. The second structural feature of complex 3 is the τ‐τ stacking interaction between two adjacent molecular planes, which forms the two‐dimentional layer structure. Besides, compared with 2, the luminescent intensity of complex 3 shows a remarkable enhancement.  相似文献   
94.
A novel 1-D Cd(Ⅱ) coordination polymer, [Cd(p-BDOA)·2H2O]n(I) ( p-BDOA2-=benzene-1,4-dioxyacetate dianion) has been synthesized and characterized by elemental analysis, IR, PL, TG and X-ray single crystal diffraction. The Crystal crystallizes in monoclinic system, the space group is C2/c, with the crystal cell parameters a=1.175 1(1) nm, b=0.551 0(1) nm, c=1.827 7(2) nm, β=96.14(2)°, and V=1.176 6(3) nm3,, Mr=372.60, R=0.045 9, wR=0.127 9. The Cd(Ⅱ) ion has a trigonal prism coordination configuration that defined by four carboxyl O atoms from two different p-BDOA2- ligands and two water molecules. Adjacent Cd(Ⅱ) ions are linked by carboxylate groups with the bidentate coordination mode, giving rise to a chain structure with the adjacent Cd…Cd distance of 1.526 3(5) nm. Furthermore, such chains are linked by hydrogen bonds to form supramolecular network. The results of PL and TG show that the complex exhibits intense fluorescent emissions and its chain skeleton is thermally stable up to 419 K. CCDC: 220443.  相似文献   
95.
96.
In the title compound, poly[μ5‐pyrazine‐2,3‐dicarboxyl­ato‐cadmium(II)], [Cd(C6H2N2O4)]n or [Cd(pdc)]n, where pdc is the pyrazine‐2,3‐dicarboxyl­ate anion, the CdII atom is six‐coordinated by five carboxyl­ate O atoms and one N atom from five different pdc ligands in a distorted octa­hedral CdO5N coordination geometry. Two CdII atoms are bridged by carboxyl­ate groups of the pdc ligands to create a dimeric unit. The dimeric units are further connected by the pdc ligands to generate an inter­esting two‐dimensional structure.  相似文献   
97.
98.
5‐Sulfosalicylic acid (5‐SSA) and 3‐aminopyridine (3‐APy) crystallize in the same solvent system, resulting in two kinds of 1:1 proton‐transfer organic adduct, namely 3‐aminopyridinium 3‐carboxy‐4‐hydroxybenzenesulfonate monohydrate, C5H7N2+·C7H5O6S·H2O or 3‐APy·5‐SSA·H2O, (I), and the anhydrous adduct, C5H7N2+·C7H5O6S or 3‐APy·5‐SSA, (II). Both compounds have extensively hydrogen‐bonded three‐dimensional layered polymer structures, with interlayer homo‐ and heterogeneous π–π interactions in (I) and (II), respectively.  相似文献   
99.
We have performed parallel tempering Monte Carlo simulations using a simple continuum heteropolymer model for proteins. All 10 heteropolymer sequences which we have studied have shown first-order transitions at low temperature to ordered states dominated by single chain conformations. These results are in contrast with the theoretical predictions of the random energy model for heteropolymers, from which we would expect continuous transitions to glassy behavior at low temperatures.  相似文献   
100.
通过考虑气候和经济社会因素,将气候因素与函数综合考虑并进行分析,构建“经济气候”模型,分析并得出气候因素对安徽省中药材产业影响程度,利用所构建BP神经网络模型,分析数据,对气象因素对中药材产业的影响结果进行预测。通过分析安徽省气候变化的特点与方向,确定气候因素对中药材产业的影响程度,为中药材产业发展提供一定的数据分析支撑,为有针对性的管理中药材产业提供方法与数据基础,同时对降低严重气象灾害对中药材生产带来的负面作用具有一定的理论与实践意义。  相似文献   
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