较快反应的热动力学天空

根据热导式热量计的工作原理,提出了热导式热量计的界面模型,建立了感温滞后条件下热量计的理论方程,从而提出了一种较快反应的热动力学研究法---失真热谱曲线修正法,并利用该法成功地研究了几个较快的准一级和等浓度二级反应的热动力学。     

较快一级化学反应的热动力学研究法: 热弛豫法

分析了非稳态传热情况下热导式热量计的动态性能,通过对输出信号的剖析,建立了热导式热量计冷却常数的经验动态模型。通过对热弛豫现象的分析,建立了可用于研究快速化学反应的热动力学研究法-热弛豫法,应用此种量热研究法可用于研究速率常数小于5s^-^1的一级化学反应。研究了25℃下乙酸甲酯、甲酸乙酯和甲酸甲酯在水溶液中的皂化反应,其计算结果与文献值相吻合,从而验证了热弛豫法的正确性。     

热动力学对比进度法IV. 热导式热量计的单参数理论模型与热谱重建

本文建立了热导式热量计的单参数理论模型, 在此基础上系统地提出了热谱重建法, 并结合热动力学对比进度法, 对几个化学反应体系进行了热动力学研究。实验结果验证了本文方法及其理论基础的正确性。     

热动力学对比进度法IV. 热导式热量计的单参数理论模型与热谱重建

本文建立了热导式热量计的单参数理论模型, 在此基础上系统地提出了热谱重建法, 并结合热动力学对比进度法, 对几个化学反应体系进行了热动力学研究。实验结果验证了本文方法及其理论基础的正确性。     

热动力学对比进度法V. 连续一级反应的热动力学研究法

本文导出了连续一级反应动力学和热动力学的对比进度方程, 建立了连续一级反应热动力学的数学模型。根据该模型, 可由一次实验的热谱数据同时解析出两步反应的速率常数和摩尔反应焓。采用热导式热量计研究了己二酸二乙酯皂化反应的热动力学, 实验结果验证了本文热动力学模型的正确性。     

热动力学对比进度法V. 连续一级反应的热动力学研究法

本文导出了连续一级反应动力学和热动力学的对比进度方程, 建立了连续一级反应热动力学的数学模型。根据该模型, 可由一次实验的热谱数据同时解析出两步反应的速率常数和摩尔反应焓。采用热导式热量计研究了己二酸二乙酯皂化反应的热动力学, 实验结果验证了本文热动力学模型的正确性。     

微量热法研究黄嘌呤氧化酶反应

在热导工热量计双参数理论模型的基础上，建立了较快酶仲反应研究的双参数初始速度法的热动力学模型，用微量热法研究了黄嘌呤氧化酶催化氧化黄嘌呤的热动力学，该较快酶促反应遵循Ｍｉｃｈａｅｌｉｓ－Ｍｅｎｔｅｎ这，在２９８．１５Ｋ和ＰＨ＝７．５时，其米氏常数为１．０４×１０＾－３ｍｏｌ．Ｌ＾－１，与文献结果相符。     

N-溴代丁二酰亚胺氧化异丙醇反应的热动力学研究

利用Batch型热导式热量计测定了N-溴代丁二酰亚胺(NBS)氧化异丙醇反应的热谱曲线,并分别利用简单级数反应和连续一级反应热动力学特征对比参量法的数学模型计算了反应的动力学参数,计算结果表明:利用连续一级反应热动力学研究法处理得到的动力学参数与文献通过碘量法的测定值是吻合的,因此,在质子性溶剂中的NBS氧化异丙醇反应遵从连续一级反应的动力学规律。     

热动力学对比进度法(Ⅲ)——2-Ⅰ型可逆反应的热动力学研究

本文建立了2-Ⅰ型可逆反应的热动力学对比进度方程和热动力学模型。用热导式自动热量计研究了一个2-Ⅰ型吸热反应体系,并对结果进行了讨论。     

热动力学对比进度法VI. 单底物酶促反应的热动力学研究

本文导出了单底物酶促反应的热力学变换方程组, 建立了单底物酶促反应动力学的对比进度方程和热动力学的数学模型。根据此模型, 可由一次反应的热谱曲线同时解析出动力学参数(K~m, V~m)和反应的摩尔焓(△H)。用热导式热量计研究了α-糜蛋白酶催化N-乙酰基-L-酪氨酸乙酯水解的热动力学。并对本文建立的热动力学研究法的特点作了详尽的讨论。     

Thermokinetic Research Method for Faster First-order Reaction. Double-parameter method

This paper presents a novel data processing method for thermokinetics of faster first-order reaction on the basis of the double-parameter theoretical model of a conduction calorimeter, in which the rate constant of a first-order reaction can be calculated from only four peak height data from the same thermoanalytical curve without using any peak-area. The saponifications of ethyl acetate and methyl acetate in aqueous solution and ethyl benzoate in aqueous alcohol have been studied to test the validity of this method. The rate constants calculated with this method are in fair agreement with those in literature; hence the validity of this method is demonstrated. This revised version was published online in August 2006 with corrections to the Cover Date.     

Characteristic parameter method for studying chemical kinetics in calorimeter

A novel thermokinetic research method for determination of rate constants of simple-order reaction in batch conduction calorimeter under isothermal condition, the characteristic parameter method, is proposed in this paper. Only needing the characteristic time parameter tm obtained from the measured thermoanalytical curve, the kinetic parameters of reactions studied can be calculated conveniently with this method. The saponifications of ethyl propionate and ethyl acetate in aqueous ethanol solvent, the polymerization of acrylamide in aqueous solution, the ring opening reaction of epichlorohydrin with hydrobromic acid have been studied. The experimental results indicate that the characteristic parameter method for simple-order reaction is correct. This revised version was published online in August 2006 with corrections to the Cover Date.     

连续一级反应的热动力学研究法: 自函数回归法

根据热动力学基本理论,推导出了热导式量热计测量的连续一级反应的热谱曲线的动力学解析方程,并推出了连续一级反应热动力学的自函数递推方程,由此建立了一种研究连续一级反应的热动力学新方法-自函数回归法。通过对丁二酸二乙酯和邻苯二甲酸二乙酯的皂化反应的热谱曲线分析,验证了自函数回归法的正确性。     

热动力学对比参量法 --简单级数反应

根据化学反应动力学和热动力学基本理论, 建立了简单级数反应的热动力学对比参量方程, 提出了一种新的热动力学研究法--对比参量法. 利用该法可以从一张热谱图上同时解析出化学反应的速率常数、半衰期和热动力学体系的冷却常数. 实验结果验证了方法的正确性.     

热导式热量计特征热谱方程的建立

Based on the interfacial model of a conduction calorimeter, a characteristic thermogram equation is suggested in this paper. Measurements of only two quantities such as the maximum peak height △m and its time tm, enables us to calculate the peak height at any interval by using this model. Thermograms of alkaline hydrolysis of ethyl propionate and ethyl acetate have been measured at 25℃, respectively. The themographic data calculated by using the characteristic thermogram equation are in reasonable agreement with those read from the thermograms.     

Characteristic parameter method for studying kinetics of opposing reactions in calorimeter

According to the theoretical basis of thermokinetics, the integral and differential thermokinetic equations of opposing reactions have been derived, and a novel thermokinetic research method, the characteristic parameter method for opposing reactions which taking place in a batch conduction calorimeter under isothermal condition, has been proposed in this paper. Only needing the characteristic thermoanalytical data corresponding to t_m and 2t_m from the same curve, the rate constants of forward and backward reactions and equilibrium constant can be calculated simultaneously with this method. In order to test the validity of this method, the proton-transfer reactions of nitroethane with ammonia at 15 and 25°C, and with trihydroxymethyl aminomethane (Tris) at 15 and 30°C have been studied, respectively. The results of rate constants and equilibrium constants calculated with this method are in agreement with those in the literature. Therefore, the characteristic parameter method for opposing reaction is believed to be correct.This revised version was published online in November 2005 with corrections to the Cover Date.     

慢对峙反应的热动力学对比参量法

根据热动力学基本理论,推导了对峙反应的热动力学对比参量方程,建立了对峙反应对比参量法的数学模型。该法利用特征时间t~m和2t~m时对应的热谱数据计算反应的对比参量,进而解析出较慢对峙反应的速率常数和平衡常数。利用该法分别研究了硝基乙烷与氨和三(羟甲基)氨基甲烷质子转移反应的热动力学,实验结果表明了较慢对峙反应对比参量法的正确性。     

Thermokinetics of the ethyl acetate acid and alkaline hydrolysis by differential scanning calorimetry

The kinetic investigation of thermoanalytical curves for the ethyl acetate and alkaline hydrolysis, requires tedious calculations of several mathematical expressions, to establish the correlation between the thermochemical and kinetic parameters. Using the DSC measured data for the heat flow-temperature dependence of the studied reactions, we have obtained the kinetic bulk parameters and the dependencek=k(T) for the basic and acid hydrolysis of ethyl acetate.     

Calorimetric Reaction Rate Determination with the Characteristic Kinetic Parameter Method

On the basis of the theory of thermokinetics proposed in the literature, a novel thermokinetic method for determination of the reaction rate, the characteristic parameter method, is proposed in this paper. Mathematical models were established to determine the kinetic parameters and rate constants. In order to test the validity of this method, the saponifications of ethyl benzoate, ethyl acetate and ethyl propionate, and the formation of hexamethylenetetramine were studied with this method. The rate constants calculated with this method are in agreement with those in the literature, and the characteristic parameter method is therefore believed to be correct.In the light of the characteristic parameter method, we have developed further two thermo-kinetic methods, the thermoanalytical single and multi-curve methods, which are convenient for simultaneous determination of the reaction order and the rate constant. The reaction orders and rate constants of the saponifications of ethyl acetate and ethyl butyrate and the ring-opening reaction of epichlorohydrin with hydrobromic acid were determined with these methods, and their validity was verified by the experimental results.This revised version was published online in November 2005 with corrections to the Cover Date.