一水合碱式苯甲酸铁(Ⅲ)的流变相法合成及热分解研究

芳香族羧酸配合物有许多特殊的功能,如稀土离子芳香族羧酸配合物在紫外线的激发下可产生稀土离子的特征跃迁发光,这类配合物可用于制造照明材料、增感材料、显示材料及装饰用材料。芳香族羧酸配合物在热分解过程中产生各种分子片,利用热分解生成的分子片使合成新型芳香族有机金属化合物和一些新的功能材料成为可能[1-7],对碱土金属、稀土金属苯甲酸盐的热分解机理已有报道[8-12],这类配合物的热分解可能为某些有机化合物的合成提供简便易行的绿色合成方法[7]。为了系统地探索金属苯甲酸盐的热分解规律,我们选用铁的苯甲酸配合物为研究对象,…     

稀土氨基酸配合物RE(Val)Cl3•6H2O(RE = Nd，Sm)的热分解动力学

合成了稀土氨基酸配合物晶体——三氯化缬氨酸六水合钕、钐，对合成样品进行了EDTA滴定、元素分析、红外光谱分析、热重、差热分析以及熔点测定，推测了配合物的热分解机理，采用Achar法和Coats-Redfern法研究了配合物热分解的非等温动力学过程，给出了各配合物样品失水阶段第一步反应和氨基酸骨架断裂阶段第一步反应的活化能（E）、指前因子的对数值（ln(A)）及热分解反应动力学方程式.     

Er2(PhCH2COO)6·4H2O的结构及热分析

用X-射线四圆衍射仪测定了Er_2(PhCH_2COO)_6·4H_2O的晶体结构。配合物属于单斜晶系, 空间群为P2_1/α, 晶胞参数:α=0.9008(3) nm, b=1.4243(5) nm, c=1.8437(7) nm, β=98.80(3)°, V=2.337(1) nm~3, Z=4. 采用TG-DTG-DTA研究了配合物的热分解过程, 确定了热分解机理。采用Freeman-Carroll方法计算了配合物脱水过程的活化能和反应级数。用DSC测定了配合物脱水, 熔化过程的焓变。     

含能配位聚合物[Cu(tza)2]n的晶体结构、热分析、感度和催化性能

以碱式碳酸铜和四氮唑乙酸在水中反应制备得到四唑乙酸铜(II)含能配位聚合物, 并培养出单晶. 运用元素分析, FT-IR分析和X-射线单晶衍射对标题配合物的组成和结构进行了全面的表征. 采用差示扫描量热分析(DSC)和热重-微分热重分析(TG-DTG)研究了标题配合物的热分解过程, 表明标题配合物的热分解主要包含三个放热峰. 用Kissinger和Ozawa-Doyle法对标题配合物的第一放热分解过程进行了动力学研究, 计算得到其活化能为356.1 kJ/mol. 对配合物的撞击、摩擦、火焰感度和5s爆发点测试表明该配合物具有一定的感度, 有望作为含能材料应用于相关领域. 同时研究了标题配合物对RDX热分解的影响, 结果表明: 标题配合物可以使RDX的放热分解峰的温度提前16.4 ℃,分解速度加快, 对RDX具有良好的催化作用.     

配合{Cd（phen）[（C6H5）2C（OH）COO]2}2·H2O的合成、晶体结构及荧光性质

羧酸配合物在配位化学中占有重要地位。羧酸配合物有丰富的拓扑结构、较高的稳定性,在磁学、光学、催化、生物等诸多领域有广泛的应用前景,羧酸配合物引起了人们广泛的兴趣和极大的关注^[1-3]。近年来,我们用小位阻的羧酸配体合成了一些羧酸配合物^[4-6],而对于大位阻的羧酸配体体系我们研究很少。     

铜(Ⅱ)与N-(2-羟基乙基)水杨醛亚胺配合物热分解非等温动力学的研究

本文利用TG,DTG技术研究了铜(Ⅱ)与N-(2-羟基乙基)水杨醛亚胺配合物的热分解过程,借助TG,DTG曲线,采用Achar法和Coats-Redfern法, 通过对比不同机理时的动力学参数,推断出第一,三两步热分解反应的可能机理, 求出了该配合物热分解的非等温动力学数据.其机理为三维扩散,#D(圆柱形对称)     

配合物{Cd(phen)[(C6H5)2C(OH)COO]2}2·H2O的合成、晶体结构及荧光性质

羧酸配合物在配位化学中占有重要地位.羧酸配合物有丰富的拓扑结构、较高的稳定性,在磁学、光学、催化、生物等诸多领域有广泛的应用前景,羧酸配合物引起了人们广泛的兴趣和极大的关注[1～3].近年来,我们用小位阻的羧酸配体合成了一些羧酸配合物[4～6],而对于大位阻的羧酸配体体系我们研究很少.二苯乙醇酸是一种大位阻的柔性芳香羧酸,文献报道的二苯乙醇酸配合物不多[7-9].     

对甲苯基烷基亚砜与钯(Ⅱ)配合物的合成及热分析研究

对甲苯基烷基亚砜(RSOPhCH_3)对钯的萃取研究及其与钯(Ⅱ)的固体配合物的合成迄今尚未见报道。本文首次制备了五种不同取代烷基的系列配体的钯(Ⅱ)配合物(R=n-C_4H_9,C_6H_(13),C_8H_(17),C_(10)H_(21)和C_(12)H_(25)),采用元素分析、红外光谱等方法鉴定其组成。由于研究该系列配合物的性质,如热稳定性等能有助于对它们萃取机理的进一步探索,因此,本文应用热重分析法(TG-DTG)研究了配合物的热分解过程,分别应用Freeman-Carroll,Coats-Redfern和Kissinger方程获得了它们的热分解活化能,并讨论了配合物的热分解行为与配合物配体中取代烷基之间的关系。     

配合物[Eu(4-MOBA)3(terpy)(H2O)]2的合成、表征、热分解机理及性质

合成了一个新的配合物[Eu(4-MOBA)₃(terpy)(H₂O)]₂ (4-MOBA:4-甲氧基苯甲酸根, terpy:2, 2':6', 2"-三联吡啶)。采用傅里叶变换红外(FTIR)光谱、元素分析和X射线粉末衍射(XRD)技术对标题配合物进行了表征,用X射线单晶衍射仪测定了配合物的晶体结构,在配合物中每个Eu³⁺离子与一个三联吡啶分子、一个水分子和三个羧酸分子结合,配位数为9,羧酸基团的配位模式包含三种:双齿螯合,桥连双齿,单齿。根据热重-差示扫描量热/傅里叶变换红外(TG-DSC/FTIR)联用技术,研究了配合物的热分解机理。配合物的发射光谱显示出Eu³⁺离子的特征荧光发射,表明三联吡啶和4-甲氧基苯甲酸在该体系中可作为敏化集团。另外,文中还讨论了配合物对白色念珠菌和大肠杆菌的抑菌活性。     

含能钴配合物的催化燃烧性能研究

水热条件下合成了一个四唑含能配合物[Co(pzta)(H_2O)_2](pzta=5-吡嗪基四唑)。运用TG-DSC热分析仪研究了配合物的热分解行为;在非等温条件下,采用Kissinger's和Ozawa-Doyle's两种方法,对配合物进行了非等温动力学研究,得到它的表观活化能(E=153.63 k J mol-1)。利用DSC技术分析了配合物对AP和HMX热分解行为的影响,结果表明:配合物的加入对于HMX的放出的热量和峰温影响不大;使AP的分解峰温提前不多,但是加入配合物后呈现出的剧烈放热过程,放热量增加,因此配合物对AP具有较好的催化燃烧效果。     

Kinetics of the non-isothermal decomposition of Cu-and Co-itaconato complexes

The kinetics of the thermal decomposition of Cu- and Co-itaconato complexes were studied using dynamic thermogravimetric techniques. The dehydration process was found to proceed in a one-stage reaction, while the thermal decomposition of the anhydrous salts was followed a two-stage reaction. The first stage is the decomposition of the complex to metal carbonate, whereas the second stage is the decomposition of the formed carbonate to the oxide. Kinetic analysis of the dynamic TG curves were discussed with reference to a composite integral method on comparison with the integral methods of Coats and Redfern and Ozawa. The activation parameters were calculated and discussed for each decomposition step.     

TG,DTA and electrical conductance properties of some Cu(II) AND Mn(II) bisazo- dianils complexes

The TG and DTA of a new series of Mn(II) and Cu(II) complexes with a number of newly prepared bisazo-dianil ligands were studied in the temperature range (20-700°C). The TG and DTG curves display to main steps, the first one within the temperature range (25-330°C) correspond to the elimination of water or and ethanol from the complexes. The second step within the range (350-625°C) is due to the decomposition of the complexes yielding the metal oxides as the final product. The rate constants of the dehydration and decomposition reactions were determined, from which some kinetic parameters were evaluated. The DTA curves show that the dehydration of the metal complexes is an endothermic reaction. In all cases the anhydrous metal complexes undergo exothermic decomposition reactions to give the metal oxide. The thermodynamic parameters (ΔE, ΔH, ΔS, ΔG) for the occurring processes are calculated. The electrical conductivities of the solid complexes were measured and the activation energy of the complex and its free ligand are also calculated. This revised version was published online in August 2006 with corrections to the Cover Date.     

Thermal Studies on Solid Complexes of Uracil With Some Divalent Transition Metal Ions

The thermal behaviour of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pd(II) complexes of uracil was studied by TG, DTG and DTA in a dynamic nitrogen atmosphere. Two processes occur in the isolated uracil complexes: dehydration and pyrolytic decomposition. In the hydrated complexes, the first stage observed was the loss of water molecules, which was followed by decomposition of the uracil. The thermal dehydration of the complexes occurred in from one to three steps. The final decomposition products were found to be the respective metal oxides, except in the cases of the Co(II) and Pd(II) complexes, which produced metallic cobalt and palladium, respectively. The order of reaction and energy of activation for the dehydration stage were evaluated.This revised version was published online in November 2005 with corrections to the Cover Date.     

Thermal decomposition of scandium(III) benzenetricarboxylates in air and nitrogen atmospheres

The conditions of thermal decomposition of scandium(III) hemimellitate, trimellitate and trimezinate in air and nitrogen atmospheres have been studied. On heating, the benzene-tricarboxylates of Sc(III) decompose in two stages. First, the hydrated complexes lose crystallization water; heating in air finally yields Sc₂O₃, and heating in a nitrogen atmosphere Sc₂O₃ and C. The dehydration of the complexes is associated with strong endothermic effects. The decomposition of benzenetricarboxylates in air is accompanied by an exothermic effect and in nitrogen by an endothermic effect. The activation energies of the dehydration and decomposition reactions have been calculated for the Sc(III) benzenetricarboxylates.     

Structural and thermal decomposition characteristics of mixed-ligand complexes of Cu(II), Ni(II), Co(II) and Zn(II)

Mixed-ligand complexes of Cu(II), Ni(II), Co(II) and Zn(II) with 8-hydroxyquinoline and thiophene-2-carboxylic acid as two different ligands, have been isolated in pure state. The formation of these complexes has been inferred potentiometrically. The isolated complexes have been characterized by their elemental analyses, IR and electronic spectra, conductivity and magnetic measurements. Solid state dehydration of the hydrated complexes and subsequent decomposition of the anhydrous complexes have been studied by simultaneous DTA and TG techniques. The thermal stability order of the hydrated compounds is Cu>Co>Ni>Zn, but in the decomposition process the trend observed is Co>Zn>Ni>Cu. Some parameters like activation energy and order of reaction for each process have been computed.     

Thermal decomposition of 8-hydroxyquinoline complexes with aluminium,cobalt, manganese and nickel

The conditions of thermal decomposition of aluminium(III), cobalt(II), manganese(II) and nickel(II) 8-hydroxyquinoline complexes have been studied by TG-DSC analysis. The thermal decomposition of these complexes has two stages: dehydration and loss of 8-hydroxyquinoline. The final solid product is an oxide.     

Preparation, thermal decomposition and lifetime of europium tris(dibenzoylmethanato)phenanthroline complex doped xerogel

The Eu tris(dibenzoylmethanato)phenanthroline complex doped xerogel has been synthesized by a catalyst-free sol-gel roure. The non-isothermal kinetic analysis is calculated by Friedman isoconversional method and multivariate non-linear regression method. The overall decomposition process below 600°C is fitted by an Fn model (n order reaction), corresponding to the dehydration of the matrix, and a two-step consecutive reaction of Cn model (n order autocatalytic reaction), corresponding to the decomposition of organic complex. Correlation coefficient is 0.99986. The lifetime values of xerogel, defined as the 5% decomposition of europium organic complex, indicate that the xerogel can find application at near room temperature.     

Thermal Studies on Solid Complexes of Saccharin with Divalent Transition Metal Ions

The thermal decompositions of Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes of saccharin were studied in static air atmosphere. All of the complexes contain four molecules of coordination water and two molecules of crystallization water. The water molecules were removed in a single stage, except from the Zn(II) complex, which exhibited two endothermic effects. The dehydration process was usually accompanied by a sharp colour change. The anhydrous complexes exhibited a phase transition and the decomposition or combustion of saccharin occurred in the second and subsequent stages. The final decomposition products were identified by XRPD as the respective metal oxides. The kinetic parameters, such as the order of reaction and energy of activation for the dehydration stage, were evaluated and the thermal stabilities of the complexes are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermogravimetric analysis: temperature limits and rate of heating

In the case of the decomposition of carbonates and hydrates, the Polanyi-Wigner equation often applies. A mathematical expression relating the temperature at a given stage of the reaction to the rate of decomposition, fraction of reactant left, initial weight and area of the compound and finally the rate of heating has been derived from the above equation. For a given thermobalance the minimum detectable rate of decomposition and fraction of reactant left are fixed so that the observed final decomposition temperature is a function of the rate of heating for a constant weight and area of material. Using this equation, values for the final decomposition temperatures have been calculated and compared with data found in the literature for the decomposition of calcium carbonate and for the dehydration of potassium chrome alum and orthoboric acid. The equation also has been applied to the dehydration of 5-nitrobarbituric acid trihydrate as determined by us.