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1.
People have long been interested in the coordination polymers of terbium! with carboxylic acids for those polymers often have peculiar structure and luminescent feature. They can be used as extraction and separation agents, bactericides, luminescent and functional materials. For example, they are used in the production of plastic membranes, lighting materials, developing materials and ornament materials[1~3]. In chemical literature, we can find many research reports about ternary complexes of…  相似文献   

2.
1 INTRODUCTION There is considerable interest in the heteropolymetalates in view of their potential applications in many fields, such as, catalysis, biology, medicine, magnetochemistry, and materials science[1~5]. It has been well- known that the rare earth elements are highly oxophilic and the anion of polyoxomolybdates have oxygen-rich composition, which can be used as synthons for the construction of novel heteropolymetalates. Since the structure of polyoxoanion 36-molybdate Mo36O1128…  相似文献   

3.
1 INTRODUCTION Crystal engineering and the design of solid-state architectures have recently become areas of increasing interest[1, 2]. Such crystal engineering may afford new materials with useful properties such as catalytic activity, micro-porosity, nonlinear optical activity, cooperative magnetic behavior and so on. Polynitrile-ligand is one of the ideal multi-functional ligands for crystal engineering and many complexes with polynitriles as ligands have been found to show the spe…  相似文献   

4.
<正> INTRODUCTION. In the study of synthetic methods and chemical reactions of Mo-Fe-S cluster compounds for simulation of the catalytic active center of nitrogenase, the reaction.systems of MoS_4~(2-) and varios ferric or ferrous salts have caused the interests of many chemists. We have been studying the system of ferrous thiolates and thiomolybdates and found interesting results. In a previous paper, we reported the syn-  相似文献   

5.
Polyoxometalates may be versatile inorganic building blocks for the construction of molecular-based materials. By means of their multiple coordination requirements and oxophilicity, lanthanide cations are suitable to link polyoxometalate building blocks to form new classes of materials with potentially useful magnetic and luminescent properties1-4. Peacock and Weakley studied the interactions between the [α-SiW11 O39]8? isomer and lanthanide cations5, and they reported that the [α-SiW11O39…  相似文献   

6.
Open-framework materials are of great interestfrom both the theoretical and practical points of viewdue to their catalytic, absorbent, and ion-exchangeproperties[1]. In the past decade, the study of structur-ally and chemically diverse open framework solids hasbeen flourishing[2—7]. A large variety of silicates[2],phosphates[3]and carboxylates[4]with open-frameworkstructures have been synthesized with organic amines astemplates. Ithas also been demonstrated thatother oxy-salts such as selenat…  相似文献   

7.
1 INTRODUCTION There is increasing interest in the study of orga-notin carboxylic ester compounds due to their insec-ticidal, fungicidal and antibiotic activities[1, as well 2]as structure diversity. In recent years many organo-tin carboxylic ester compounds with good biologi-cal activity have been synthesized[3, . Previous stu- 4]dies show that the coordination geometry of centralatom Sn …  相似文献   

8.
1 INTRODUCTION Organic-inorganic hybrid materials and polyoxo-metalates have received much attention because of their intriguing structural diversity and potential applications in molecular adsorption, ion exchange, heterogeneous catalysis and nanotech nology as well as in electrical, magnetic and photochemical areas[1, 2]. One of the important ad- vances in the design of new organic-inorganic hybrid materials is utilizing poly- oxometalates’ coordination ability to produce poly- oxoanio…  相似文献   

9.
1 INTRODUCTION In the last decade, cyano-bridged Prussian Blueanalogues[1] have been intensively studied from theviewpoint of application as functionalized molecule-based magnets[2], chemical sensor materials[3], fluo-rescent materials[4] and zeolitic-type materials[5, , 6]etc. In 1976, a series of cyano-bridged three-dimen-sional rare earth hexacyanometalates(IIILnM(CN)6?nH2O (M = Fe or Cr, n = 4 or 5) were crystallized andsubjected to single-crystal X-ray analysis[7]. …  相似文献   

10.
1 INTRODUCTION The binding of metal ions by proteins and pep- tides is of fundamental interest due to the impor- tance of metal ions in biological systems. Metals may be part of the active sites of enzymes, stabilize the macromolecular structure of proteins and affect enzymes or membranes to control cell metabolism[1]. Therefore, for many years there has been a great in- terest in the study of complexes able to mimic these active sites of metalloproteins. In this case, metal complexes of…  相似文献   

11.
Chromium(III)isanessentialtraceelement.Inanactiveform.chronlium(III)asacomponentofglucosetolerancefactor(GTF)canimproveinsulinbiologicalactivity.CrsupplementationinhumansandanimalsreducessymptomsofTypeIIdiabetesandhypoglycemia.Forabetterunderstandingofthenatureofbiologicallyactivechromium(ill)complex,manyGTFmodelcomplexeshavebeenstudiedpreviously'.Here,oneGTFmodelcomplexofN,N'-ethylenebis(salicylideneiminato)diaquochromium(ill)chloride,[Cr(salen)(H,O)=]CIwaspreparedandcharacterized.a…  相似文献   

12.
Eu2(p-ClC6H4COO)6(C12H8N2)2配合物热分解机理及非等温动力学   总被引:2,自引:0,他引:2  
The thermal decomposition behaviour of europium p-chlorobenzoate complex with 1, 10-phenanthroline and its kinetics were studied in nitrogen by non-isothermal thermogravimetry.Its thermal decomposition occurs mainly in three steps..The intermediate and residue for each step of decomposition were identified from TGcurve.The kinetic parameters were obtained from analysis of the TG-DTG curves by the Achar method.the Madhusudanan- Krishnan-Niman (MKN) method and Ozawa method respectively.The most probable mechanisms function for the first and second stage were suggested by comparing the kinetic parameters.  相似文献   

13.
用磷钼酸与咪唑合成了一种新的杂多酸-有机电荷转移盐(C3H5N2H)3[PMo12O40]。通过元素分析、红外光谱、固体漫反射光谱、电子自旋共振及热分析等测试技术对其进行了表征,用单扫描法(Achar法和Coats-Redfern法)对合成化合物的TG分析结果进行了非等温热分解动力学研究。推断结果表明,合成化合物的第1步热分解为球对称的三维扩散机理(n=2),其动力学方程为dα/dt=1.58×108[1-(1-α)1/3]-1(1-α)2/3exp(-40931.0/T),求得分解反应的表观活化能E=340.30kJ/mol,指前因子A=1.05×108s-1。标题化合物对紫外光具有光致变色性质,用固体漫反射光谱研究了其光致变色反应动力学。结果显示,其光致变色反应表现为一级或准一级动力学,速率常数k=9.80×10-5s-1。  相似文献   

14.
Studies of the non-isothermal decomposition of M (mnt) (5-NO2-phen) (M=CoII, CuII, ZnII) were carried out by thermogravimetry. The thermal decomposition mechanisms and associated kinetics have been investigated. The kinetic parameters were obtained from an analysis of the TG–DTG curves by integral and differential methods. The most probable kinetic model functions were suggested by comparison of the kinetic parameters. Mathematical expressions for the kinetic compensation effect were derived.  相似文献   

15.
Zr(OH)4的热分解及ZrO2的相变过程   总被引:1,自引:0,他引:1  
利用TG-TDG-DTA热分析技术研究了由Zr(OH)4热分解制备ZrO2的脱水过程,并结合X射线粉末衍射技术研究了ZrO2的相变过程.发现在82℃的吸热峰对应Zr(OH)4的脱水,而435℃附近出现的放热峰则为四方ZrO2向单斜ZrO2的晶相转变.采用外推法确定了Zr(OH)4脱水过程遵循三维扩散机理,其函数方程为g(α)=[{1/(1-α)}^1/3-1]^2.以实验获得的动力学参数ln A和E为基础,用最小二乘法对ln A和E进行线性拟合,得到动力学补偿效应表达式为ln A=0.437E-20.69.  相似文献   

16.
The thermal decomposition of Eu2(BA)6(bipy)2 (BA=C2H5N 2, benzoate; bipy=C10H8N2, 2,2'-bipyridine)and its kinetics were studied under the non-isothermal condition by TG-DTG, IR and SEM methods. The kinetic parameters were obtained from analysis of the TG-DTG curves by the Achar method, the Madhusudanan-Krishnan-Ninan (MKN) method, the Ozawa method and the Kissinger method. The most probable mechanism function was suggested by comparing the kinetic parameters. The kinetic equation for the first stage can be expressed as: dα/dt=Aexp(–E/RT)3(1–α)2/3. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Barium(II) tetraphenylborate, Ba(Bph4))2·4H2O was prepared, and its decomposition mechanism was studied by means of TG and DTA. The products of thermal decomposition were examined by means of gas chromatography and chemical methods. A kinetic analysis of the first stage of thermal decomposition was made on the basis of TG and DTG curves and kinetic parameters were obtained from an analysis of the TG and DTG curves using integral and differential methods. The most probable kinetic function was suggested by comparison of kinetic parameters. A mathematical expression was derived for the kinetic compensation effect.  相似文献   

18.
HRh[(C_6H_5)_2PCH_2CH_2P(C_6H_5)_2]_2(分子量900.8)晶体属单斜晶系,空间群P21/n,晶胞参数a=21.319(2),b=20.844(2),c=10.130(3),β=91.255(2)°,V=4500.4,Z=4,D_c=1.15g·cm~(-3),F(000)=1864,μ(CuKα)=44.97cm~(-1)。共收集独立衍射点数7636个,其I>3σ(1)的衍射点数6810个。最终的R=0.045,R_w=0.050(W=1/σ~2(F)+(F)+g|F|~2)。其分子结构呈畸变的三角双锥构型。  相似文献   

19.
The thermal analysis of Ni(II) and Pd(II) complexes with thiophene-2-carboxaldehyde thiosemicarbazone have been studied using TG technique. Their decompositions are subjected to critical evaluation using the equations of Coats-Redfern, Horowitz-Metzger and modified Horowitz-Metzger and the kinetic parameters (non-isothermal method) have been evaluated for each step of decomposition by the method of weighted least-squares.  相似文献   

20.
本文报告用单晶X-射线衍射法测定[Nd_2O(C-5H_5)_6](C_(12)H_9N_2)_3C1·mC_4H_5O的晶体结构。晶体属于单斜晶系,空间群为P2-1/c,晶胞参数为a=20.982(15),b=11.217(7),c=32.954(32),β=104.17(7)°;Z=4。Nd和C1原子坐标用直接法定出,其他原子坐标以差Fourier方法求得,经过最小二乘法修正,R因子为0.159。在分子中三个茂环皆通过η~5。键与Nd原子配位,两个Nd原子间存在桥氧原子,因而形成(Nd_2O(C_5H_5)_6)~(2-)阴离子,Nd-C键基本上属于离子键。三个邻菲罗啉基团通过氢键与C1原子连接形成大的阳离子[(C_(12)H_9N_2)3-C1]~(2+)。  相似文献   

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