镧与L-酪氨酸和甘氨酸三元固态配合物的热化学研究

由于稀土元素镧与氨基酸形成的配合物具有抗癌、抗肿瘤活性 ,人们对稀土氨基酸配合物的研究产生了浓厚兴趣。有关这类配合物的制备和表征的研究较多[1～ 4] ,而对其热化学性质的研究较少。我们按文献[5] 方法合成了配合物Ｌａ(Ｔｙｒ)(Ｇｌｙ) 3Ｃｌ3·3Ｈ2 Ｏ(ｓ) ,在自行研制的具有恒定温度环境反应热量计上 ,分别测定了Ｌａ2 Ｏ3(ｓ)、氨基酸 [Ｌ 酪氨酸 (Ｌｙｒ) +甘氨酸 (Ｇｌｙ) ]和配合物在2ｍｏｌ·Ｌ- 1 ＨＣｌ溶液中的溶解焓 ,通过设计的热化学循环得出配合反应焓 ,进而计算出Ｌａ(Ｔｙｒ)(Ｇｌｙ) 3Ｃｌ3·3Ｈ2 Ｏ(ｓ)的标准摩尔…     

氯化镧与甘氨酸配位反应的热化学研究

The reaction enthalpy of coordination reaction of lanthanum chloride with Glycine is determined by solution calorimetry in an isoperibel reaction calorimeter. The calormetric solvent is the solution of hydrochloric acid (2 mol·L- 1), a new thermochemical cycle is designed. According to the results, the following date:()(298.2 K)=- 4.310 kJ·mol- 1()(La(Gly)3Cl3· 5H2O, s, 298.2 K)=- 4222.93 kJ·mol- 1 were obtained.     

稀土硝酸盐甘氨酸固体配合物热化学研究

稀土硝酸盐甘氨酸固体配合物热化学研究刘宗怀，宋迪生，刘翊纶（宝鸡文理学院化学化工系，宝鸡７２１００７）（西北大学化学系，西安７１００６９）本文在稀土硝酸盐甘氨酸固体配合物合成、表征工作基础上［１］，应用ＴＧ－ＤＴＧ、ＤＳＣ分析讨论了配合物热分解过程，...     

氯化钆与L-酪氨酸和甘氨酸三元固态配合物的热化学及热分解动力学研究

合成表征了氯化钆与L 酪氨酸和甘氨酸形成的三元固态配合物Gd(Tyr) (Gly) 3 Cl3 ·3H2 O .用具有恒温环境的溶解 -反应热量计 ,测定了配位反应GdCl3 ·6H2 O (s) +Tyr (s) +3Gly (s) =Gd(Tyr) (Gly) 3 Cl3 ·3H2 O (s) +3H2 O (l)在 2 98.15K时的反应焓为 ( 9.45 1± 0 .468)kJ·mol-1 .计算得配合物Gd(Tyr) (Gly) 3 Cl3 ·3H2 O (s)在 2 98.15K时的标准摩尔生成焓为ΔfH m =-( 4 2 69.7± 2 .3 )kJ·mol-1 .并用热分析手段对配合物进行了非等温热分解动力学研究 ,推断配合物第二步热分解反应机理为二级化学反应 ,其动力学方程为 :dα/dT =(A/β)exp( -E/RT) ( 1-α) 2 ,求得分解反应的表观活化能为E =2 15 .17kJ·mol-1 ,指前因子为 10 1 8.71 s-1 .     

高氯酸铒与甘氨酸和丙氨酸配合物的合成及其晶体结构

在水溶液中合成了高氯酸铒与甘氨酸和丙氨酸混配配合物［Ｅｒ＿２（Ｇｌｙ）＿４）（Ａｌａ）＿２（Ｈ＿２Ｏ）＿４］（ＣｌＯ＿４）＿６·３Ｈ＿２Ｏ，测定了其单晶结构。晶体属三斜晶系，Ｐ１空间群。晶胞参数为ａ＝１．１２８６（５）ｎｍ，ｂ＝１２４４ｂ（２）ｎｍ，ｃ＝０．９４２３（２）ｎｍ，ａ＝７７．６３（２）°，β＝７５２７（２）°，γ＝６４．４５（２）°，Ｖ＝１．１４６６（５）ｎｍ￣３Ｚ＝１，Ｄ＿ｃ＝２．１５４ｇ／ｃｍ￣３。该配合物为链状分子，甘氨酸和丙氨酸的羧基均以桥式与相邻的两个铒离子配位，铒的配位数为８，形成四方反棱柱型配位多面体。     

氯化钐与甘氨酸配合物Sm(Gly)2Cl3·3H2O热化学研究

A complex of samarium with glymine， [Sm(Gly)₂Cl₃·3H₂O]， was synthesized and characterized by DSC， TG and DTG. A possible mechanism of thermal decomposition of this complex was suggested. The heat capacities of the complex were measured by a precision adiabatic calorimeter over the temperature range from 82 to 375 K. The solution enthalpies of reactants [SmCl₃·6H₂O+2Gly] and the products [Sm(Gly)₂Cl₃·3H₂O+3H₂O] were determined by an isoperibel solution- reaction calorimeter at 298.15 K， respectively; the standard molar enthalpy of formation of [Sm(Gly)₂Cl₃·3H₂O] was calculated through a designed thermochemical cycle.     

L-丙氨酸和L-组氨酸与铜离子混配合物的热化学

合成了一种新的氨基酸与铜 (Ⅱ )混配型配合物 ,并用具有恒定温度环境反应热量计 ,测定了配合物和反应物在 2 98 2K时 2mol·L-1HCl溶液中的溶解焓 ,由设计的热化学循环得出了配合反应焓变ΔrHm =1 45 92kJ·mol-1,根据热力学原理计算出该配合物的标准摩尔生成焓ΔfHm ,[Cu(Ala·His) ]·4H2 O =-2 0 0 6 5 8kJ·mol-1,为进一步研究这类物质提供了热化学基础参数。     

量热法测定氯化钐与甘氨酸配合物的标准生成焓

稀土在生命科学领域的研究日益受到人们关注,稀土化合物所具有的抑菌、抑癌、消炎等作用及其作用机理的探讨已有报道［１～３］。最近几年稀土在生物领域中的研究又有了新的突破和进展,从稀土与氨基酸、蛋白质、膜脂及膜蛋白的作用到其对ＤＮＡ。ＲＮＡ的影响［１,４］,从稀土的分子水平、细胞及亚细胞水平到动物整体实验的系统研究［５,６］等,分别从不同的层次、不同的水平研究了稀土的生物效应。但至目前为止,稀土的生物效应机理及其对人体的影响尚未得到令人满意的解释。由于氨基酸是构成人体蛋白质的基本单位,故研究稀土与氨基…     

铈和硫代脯氨酸、水杨酸三元配合物的热化学性质

用七水合氯化铈与硫代脯氨酸(C4H7NO2S)和水杨酸(C7H6O3)合成了三元固体配合物[Ce(C7H5O3)2(C4H6NO2S)]·2H2O。根据盖斯定律设计一个热化学循环,用恒温环境的溶解―反应量热法研究得到合成反应的标准反应焓为263.12±0.95 kJ/mol,进而算出配合物298.15 K时的标准摩尔生成焓为-2785.7±3.2 kJ/mol。     

丙氨酸稀土二元和三元配合物的pH电位法研究

本文报道在生理条件下(37℃,I=150 mmol/L NaCl)用pH电位法研究Ala-Ln、GIu—Ln及Ala-Glu-Ln中(Ala=L-丙氨酸,Glu=L-谷氨酸,Ln=Ce,Pr,Nd,Y)二元及三元配合物的稳定常数,运用MINIQUAD-82A程序确定粒子组成,并由COMPLEX程序获得配位粒子分布图,结果表明,三价稀土离子形成配合物的稳定顺序为:Ce相似文献   

三元配合物Tb(Et2dtc)3(phen)的热化学性质

以铜试剂(NaEt2dtc•3H2O)和邻菲咯啉(o-phen•H2O) 与水合氯化铽(TbCl3•3.75H2O)在无水乙醇中制得了三元固态配合物.化学分析和元素分析确定其组成为Tb(Et2dtc)3(phen).IR光谱研究表明配合物中Tb3＋与NaEt2dtc中的硫原子双齿配位,同时与phen的氮原子双齿配位.用Calvet微热量计测定了298.15 K下液相生成反应的焓变ΔrHmθ(l),为(－21.819±0.055) kJ•mol－1,通过热化学循环计算了固相生成反应焓变ΔrHmθ(s),为(128.476±0.675) kJ•mol－1.改变反应温度,研究了液相生成反应的热动力学.用精密转动弹热量计测得配合物的恒容燃烧能ΔcU为(－17646.95±8.64) kJ•mol－1,经计算其标准燃烧焓ΔcHHmθ和标准生成焓ΔfHmθ分别为(－17666.16±8.64) kJ•mol－1和(－1084.04±9.49) kJ•mol－1.     

Thermochemistry of the Ternary Complex Nd（Et2dtc）3（phen）

Introduction A series of lanthanide sulfide complexes have beenlargely used for ceramics and thin film materials1 andthese complexes could be prepared from the precursorswhich are the compounds containing lanthanide-sulfurbonds.2-4 For instance, the compounds synthesized with[(alkyl)2dtc]-, phen?H2O and lanthanide salts were usedas the volatile precursors for preparing lanthanide sul-fide, its friction properties in lubricant was investigatedin literature 5 and the preparation and propertie…     

Ternary Molecular Complex in the Alternating Copolymerization of Methyl Methacrylate with Styrene Using Stannic Chloride

The equimolar alternating copolymerization of methyl methacrylate (MMA) with styrene (St) in the presence of stannic chloride in toluene (Tl) is investigated kinetically. The concentrations of the ternary molecular complexes, [SnCl₄-MMA … St] and [SnCl₄-MMA … T1], are calculated by use of the formation constants of the ternary molecular complexes. The rates of copolymerization under photo-irradiation and with tri-n-butyl boron-benzoyl peroxide as an initiator are proportional to the 1.5th order and 1. Oth order, respectively, of the concentration of the ternary molecular complex [SnCl₄ · MMA … St]. The alternating copolymerization precedes the homopolymerization of the methyl methacrylate charged in excess. The alternating regulation of the copolymerization is ascribed to the homopolymerization of the ternary molecular complex from the kinetic results. The magnitudes of the shifts for     

铕-8-羟基喹啉-噻吩甲酰基三氟丙酮三元固体配合物的合成和表征

以8-羟基喹啉(8HOQ)、噻吩甲酰基三氟丙酮(TTA)为配体合成了稀土固体三元配合物。元素分析表明配合物的组成为Eu(TTA)(8HOQ)2·H2O。红外光谱、紫外光谱分析表明配合物中配体TTA和8HOQ均与稀土螯合配位。荧光光谱分析表明,合成的配合物根据激发光的不同,可发射蓝光和红光。以326nm激发时,发射415nm左右的蓝光和617nm的红光的混合光;以348nm激发时,主要发射618nm的红光。蓝光来自配体8HOQ的发射,而红光来自稀土离子的发射。配体TTA和稀土Eu3+之间存在高效率的能量传递。     

Spectrophotometric Determination of Molybdenum(VI) as a Ternary Complex with 4-Nitrocatechol and Benzalkonium Chloride

A new liquid—liquid extraction system for molybdenum(VI) was studied. It contains 4-nitrocatechol (4NC) as a complexing chromogenic reagent and benzalkonium chloride (BZC) as a source of heavy cations (BZ⁺), which are prone to form chloroform-extractable ion-association complexes. The optimum conditions for the determination of trace molybdenum(VI) were found: concentrations of 4NC and BZC (7.5 × 10⁻⁴ mol dm⁻³ and 1.9 × 10⁻⁴ mol dm⁻³, respectively), acidity (3.75 × 10⁻² mol dm⁻³ H₂SO₄), extraction time (3 min), and wavelength (439 nm). The molar absorptivity, limit of detection, and linear working range were 5.5 × 10⁴ dm³ mol⁻¹ cm⁻¹, 5.6 ng cm⁻³, and 18.6–3100 μg cm⁻³, respectively. The effect of foreign ions was examined, and the developed procedure was applied to the analysis of synthetic mixtures and real samples (potable waters and steels). The composition of the extracted complex was 1:1:2 (Mo:4NC:BZ). Three possible structures of its anionic part [Mo^VI(4NC)O₂(OH)₂]²⁻ were discussed based on optimizations at the B3LYP/3-21G level of theory, and simulated UV/Vis absorption spectra were obtained with the TD Hamiltonian.     

Phase Chemistry and Thermochemstry on Coordination Behavior of Zinc Chloride with Leucine

The solubility property of the ZnCl2-Leu-H2O(Leu=L-a-leucine) system at 298.15K in the whole concentration range was investigatey by the semimicro-phase equilibrium method.The corresponding solubility diagram and refractive index diagram were constructed.The results indicated that there was one complex formed in this system.namely,Zn(Leu)Cl2.The complex is congruently soluble in water.Based on Phase equilibrium data,the complex was prepared.Its composition and properties were characterized by chemical analysis,elemental analysis,IR spectra,and TG-DTG.The thermochemical properties of coordination reaction of zinc chloride with L-a-leucine were investigated by a microcalorimeter.The enthalpies of solution of L-a-leucine in water and its zinc complex at infinite dilution and the enthalpy change of solid-liquid reaction wrer determined at 298.15K.The enthalpy change of soild phase reaction and the standard enthalpy of formation of zinc complex were claculated.On the basis of experimental and calculated results,three thermodynamic parameters(the activation enthalpy,the activation entropy and the activation free energy),the rate constant and three kinetic parameters(the activation energy,the preexponential constant and the reaction order) of the reaction,and the standard enthalpy of formation of Zn(Leu)^2 (aq) were obtained.The results showed that the title reaction took place easily at studied temperature.     

Thermochemistry on Coordination Behavior of Praseodymium Chloride Hydrate with Diethylammonium Diethyldithiocarbamate

The complex of praseodymium chloride lower hydrate with diethylammonium diethyldithiocarbamate (D-DDC) has been synthesized conveniently in absolute alcohol and dry N2 atmosphere. The title complex was identified as Et2NH2[Pr(S2CNEt2)4] by chemical and elemental analyses, the bonding characteristics of which were characterized by IR spectrum.The enthalpy of solution for praseodymium chloride hydrate and D-DDC in absolute alcohol at 298.15 K, and the enthalpy changes of liquid-phase reaction of formation for Et2NH2 [ Pr(S2CNEt2)4] at different temperatures were determined by miccocalorimetry. On the basis of experimental and calculated resuits, three thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy),the rate constant and three kinetic parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of liquid phase reaction of formation were obtained. The enthalpy change of the solid-phase title reaction at 298.15 K was calculated by a thermochemical cycle.