The adsorption of isomaltotriose from aqueous solution on Ca2+ resin was investigated. The adsorption isotherm and the rate curve were determined. The pseudo-first-order model, pseudo-second-order model and the intraparticle diffusion model were used to predict the rate constants of adsorption. The activation energy of adsorption has been also evaluated using the pseudo-second-order rate constants. The results showed that the adsorption of isomaltotriose onto Ca2+ resin is an exothermically activated process. The adsorption isotherm can be described by Langmuir equation. The pseudo-second-order model can fit well to the adsorption rate curve of isomaltotriose onto Ca2+ resin. It suggests that the adsorption of isomaltotriose onto Ca2+ resin involve chemical adsorption.
The interactions of HF, H2O and NH3 with Br2 are investigated at the MP2（full）/ aug-cc-pVDZ level. It is found that two kinds of stable complexes, halogen-bonded and hydrogen-bonded complexes, exist between Br2 and HF and between Br2 and H2O. The interaction energy analysis and natural population analysis （NPA） are conducted to these two kinds of complexes, indicating the halogen-bonded complexes are more stable than the corresponding hydrogen-bonded ones, and the binding energies of the former increase in the order HFH2O for the latter.
