中文摘要：

采用平衡吸附法测定了苏云金芽胞杆菌库斯塔克亚种（Btk）蛋白在红壤和棕壤中的吸附等温线，并依据等温线进行了吸附平衡常数和热力学参数计算。在278K～318K范围内, Bt杀虫蛋白在红壤和棕壤中的吸附等温线符合Langmuir方程（R2〉0.994 1），随着吸附温度升高，Bt杀虫蛋白的吸附量和吸附平衡常数下降，而吸附分离因子RL升高。红壤吸附Bt蛋白的RL值在0.218 1～0.580 1之间，棕壤吸附Bt蛋白的RL值在0.361 7～0.754 1之间，均属于优惠吸附。Bt杀虫蛋白在红壤和棕壤中的吸附是一个自发、放热、熵增过程，红壤吸附Bt杀虫蛋白的活化能在13.43～14.78 kJ mol-1之间，棕壤吸附Bt蛋白的活化能在10.89～11.47 kJ mol-1之间。随着温度升高，活化能和吸附自由能绝对值变大，提示土壤对Bt杀虫蛋白的吸附由物理吸附向化学吸附转变。

英文摘要：

Adsorption isotherms of the insecticidal protein of Bacillus thuringiensis subsp. kurstaki （Btk） in red soil and brown soil were determined using the equilibrium adsorption method. Based on the isothems, their adsorption equilibrium constants and thermodynamic parameters were calculated. Results show that in the range between 278K and 318K, the Btk protein adsorption isotherms in red soil and brown soil followed the Langmuir equation （R2﹥0.994 1）, showing that Bt adsorption and adsorption equilibrium constant decreased with rising temperature, but separation factor constant （RL） increased in the range of 0.218 1～0.580 1 in red soil and of 0.361 7～0.754 1 in brown soil, indicating that both were of preferential adsorption. Btk protein adsorption in the two soils was a spontaneous, exothermic, entropy-increasing process. In red soil the activation energy of adsorbed Btk protein ranged from 13.43～14.78 kJ mol-1, while in brown soil it did from 10.89～11.47 kJ mol-1. Under rising temperature, it increased along with adsorption free energy, which suggests that the adsorption of Btk protein by the soils is turning from a physical process into a chemical one.