共查询到18条相似文献,搜索用时 187 毫秒
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本文综述了近年基于Tian方程建立的化学反应热动力学研究法的进展。重点评述了无量纲参教法、对比进度法、模拟热谱曲线法,特征参量法和时间变量法。 相似文献
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时间参量法(Ⅳ)──对峙反应的热动力学研究 总被引:6,自引:2,他引:4
根据热动力学基本理论和对峙反应的通用微分动力学方程,将时间作为已知参量,建立了对峙反应热动力学时间参量法的数学模型,并利用该法分别研究了硝基乙烷与氨和三(羟甲基)氨基甲烷反应的热动力学. 相似文献
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根据化学反应热动力学的基本原理.推导了连续一级反应的积分和微分热动力学方程,建立了连续一级反应热动力学时间参量法的数学模型,通过对己二酸二乙酯和邻苯二甲酸二乙酯皂化反应的热动力学研究,验证了连续一级反应时间参量法的正确性. 相似文献
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根据化学反应热动力学的基本原理,推导了连续一反应的积分和微分和微分热动力学方程,建立了连续一级反应热动力学时间参量法的数学模型,通过对已二酸二乙酯和邻苯二甲酸二乙酯皂化反应的热动力学研究,验证了连续一级反应时间参量法的确定性。 相似文献
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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. 相似文献
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绝热式热动力学的研究I:可逆反应动力学的数学模型 总被引:2,自引:0,他引:2
本文提出了几类可逆反应通用的微分动力学方程.并应用无量纲参数法,建立了可逆反应动力学的数学模型.还给出了一个解析实例. 相似文献
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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。 相似文献
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Characteristic parameter method for studying kinetics of opposing reactions in calorimeter 总被引:1,自引:0,他引:1
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 tm and 2tm 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. 相似文献
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Macitentan (MAC) is a pulmonary arterial hypertension (PAH) drug marketed as a tablet and often has stability issues in the final dosage form. Quantitative determination of MAC and its associated impurities in tablet dosage form has not been previously reported. This study quantified impurities present in Macitentan tablets using a binary solvent-based gradient elution method using reversed phase-high performance liquid chromatography. The developed method was validated per International Conference on Harmonization (ICH) guidelines and the drug product was subjected to forced degradation studies to evaluate stability. The developed method efficiently separated the drug and impurities (48 min) without interference from solvents, excipients, or other impurities. The developed method met all guidelines in all characteristics with recoveries ranging from 85%-115%, linearity with r2 ≥ 0.9966, and substantial robustness. The stability-indicating nature of the method was evaluated using stressed conditions (hydrolysis:1 N HCl at 80℃/15 min; 1 N NaOH at 25℃/45 min; humidity stress (90% relative humidity) at 25℃ for 24 h, oxidation:at 6% (v/v) H2O2, 80℃/15 min, thermolysis:at 105℃/16 h and photolysis:UV light at 200 Wh/m2; Fluorescent light at 1.2 million luxh). Forced degradation experiments showed that the developed method was effective for impurity profiling. All stressed samples were assayed and mass balance was>96%. Forced degradation results indicated that MAC tablets were sensitive to hydrolysis (acid and alkali) and thermal conditions. The developed method is suitable for both assay and impurity determination, which is applicable to the pharmaceutical industry. 相似文献