著者

松浦 巌 清家 康子 川真田 正信

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.103, no.1, pp.85-93, 1983-01-25 (Released:2008-05-30)

参考文献数

14

被引用文献数

1 1

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Kinetic analysis of thermal decomposition was carried out using thermogravimetry (TG) and differential scanning calorimetry (DSC). The linear equations of n order, phase-boundary, nucleation growth and diffusion-controlled reaction under linear heating conditions were derived for the estimation of the rate constant and the activation energy. The method to determine the reaction mechanism was shown by evaluation of linearity. The equations were applied to the TG and DSC curves of dehydration of calcium oxalate monohydrate and elimination of carbon monoxide from calcium oxalate. The dehydration was fit to two-dimensional phase-boundary reaction and the activation energy was calculated as 85 kJ/mol. But the dehydration at a high-speed heating rate proceeded as apparent three-dimensional diffusion-controlled reaction. The elimination of carbon monoxide from calcium oxalate was fit to phase-boundary reaction and the activation energy was calculated as 196 kJ/mol for three-dimensional phase-boundary reaction and 182 kJ/mol for two-dimensional phase-boundary reaction.

著者

山口 寿 川真田 正信 仲井 由宣 山本 恵司

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.102, no.5, pp.463-468, 1982-05-25 (Released:2008-05-30)

参考文献数

8

被引用文献数

1 1

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By use of X-ray diffractometry, thermal analysis and infrared spectroscopy, the crystal forms of N-(2, 6-dimethylphenyl)-Δ8-dihydroabietamide were investigated. Two polymorphic forms (form I and II), two solvates (cyclohexane and CCl4), and an amorphous form were identified. Heating of form II induced a solid transformation to form I. The transition of form I and II to the amorphous form was observed by grinding. Each solvate contained 9.0% cyclohexane and 16.0% CCl4 respectively, i.e., drug : solvent=2 : 1. The activation energy of the desolvation was determined from TG curves by using Ozawa's method, and calculated as 72.2 kcal/mol for the cyclohexar solvente, and 35.5 kcal/mol for the CCl4 solvate.