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The thermal stability and the kinetics of thermal decomposition of protionamide were studied by thermogravimetry. activation energy e-a of thermal decomposition of this substance was obtained to be 54.65 kj center dot mol(-1) by kissinger method and ozawa-flynn-wall method. kinetics model function and frequency factor a of protionamide were predicted with the malek method, which were f(alpha)=alpha(0.391)(1-alpha)(0.145) and ina=13.12, respectively. moreover, melting point, molar enthalpy and entropy of fusion of this compound were determined to be 414.09 k, 23.21 kj center dot mol(-1), and 56.06 j center dot mol(-1) center dot k-1, respectively.

The size of nano Fe powders was determined to be 25 nm in diameter by SEM. The isobaric molar heat capacity C-p of the nano Fe was measured with the high precision adiabatic low-temperature calorimeter in the temperature range from 84 K to 350 K. The relationship of C-p with temperature T was established as

The processes of thermal decomposition of salvianolic acid B were studied by TG-DTG. The TG-DTG curves showed that the process of mass loss of the substance proceeded in two steps. The first step could be attributed to the expulsion of water in the temperature range of 305 similar to 373 K. The second step was corresponding to the large scale degradation of salvianolic acid B in the temperature range of 413 similar to 864 K. The activation energies E of thermal degradation process of three stages were obtained by Friedman method and Ozawa-Flynn-Wall method. According to 15 mechanism functions, the possible kinetic model of thermal degradation process was estimated to be Fn-F2-F1 through the multiple linear regression method.