维生素C片剂分解动力学研究

A STUDY ON THE DECOMPOSITION KINETICS OF VITAMIN C TABLET

在相对湿度小于临界相对湿度的条件下,在温度为60～90℃、相对湿度为60～80％范围内测定了维生素C片剂的色泽(以相对反射率R表示)变化速率,含量C变化速率及片剂溶液的色泽(以透光率T表示)变化速率。三者的表观速率常数k与热力学温度T和相对湿度RH的关系通式为k=k’exp(-E/RT)exp(mRH),k’和m为常数,E为表观活化能。不同速率常数的k’,m和E值均不同。

Under the condition of relative humidity less than the critical relative humidity,the discoloration rate and decomposition rate of vitamin C tablet and the discoloration rate of vitamin Ctablet in solution were studied at temperatures 60～90°C and relative humidities 60%～80%. Thegeneral equation of the relationship between the apparent rate constant k, absolute temperature T andrelative humidity RH is: k=k′exp(-E/RT) exp(mRH) ,where k′and m are constants,E is apparentactivation energy. The values of k′, m and E for discoloration, decomposition and discoloration insolution are different.