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An extensive grand canonical Monte Carlo (GCMC) simulation combined with quantum mechanics calculations has been conducted to investigate the dependency of the adsorption isotherms, local density profiles, and orientational behaviors of HCFC-22 confined in pillared clays on pore width, porosity, pressure, and the density of the activated sites at 300 K. The calculated results suggest that there are optimal pore width and pressure for adsorption, and the effects of porosity and the activated sites on adsorption are significant at low pressure and become weaker with increasing pressure. A combination of the GCMC simulation and the quantum mechanics calculation results shows that hydrogen atom is the adsorption site of an HCFC-22 molecule adsorbed on the pillared clay walls and most of the molecules in the contact layers orient perpendicularly to the walls in the direction of C 3 H when physical adsorption is predominant, and the orientation changes with increasing pressure.

Atomistic molecular dynamics simulations were performed to investigate the dependence of the self-diffusivity of liquid carbon tetrachloride (CCl4) confined in pillared pore materials on the pore width, porosityand the surface heterogeneityof the solid walls. The simulated results show that the self-diffusivityof liquid CCl4 does not increase monotonicallywith the pore width, but in an cillatorymanner to approach the bulk diffusivity. Moreover, the presence of activated sites characterizing the surface heterogeneity and the pillars reduces the self-diffusivityof liquid CCl4 confined in pillared pores. The effects of these factors on the self-diffusivityof fluids should be taken into account when a porous nanomaterial is designed or chosen for a certain process, in addition to their effects on other properties such as the adsorption capability.

A quantitative structure-activity relationship (QSAR) study on inhibitory activities of 1-phenylbenzimidazoles against the platelet-derived growth factor receptor (PDGFR) was carried out in this work, and a QSAR model was developed. It gives an r2 of 0.78 for the training set of 55 active compounds, and an r2 of 0.75 for the test set of 24 active compounds. The new model was further applied to predict inhibitory activities of additional 44 inactive compounds, and very good agreement with experimental observations was obtained. The new model requires only variable connectivity indices and two position indices as input parameters, which is simple and easy to apply. The new model is useful for developing new anticancer drugs, which also demonstrates that the recently developed variable connectivity indices are very useful structural descriptors in the QSAR studies in the fields of pharmaceutics and biochemistry.

On the basis of White's theory, an improved renormalization group～RG! theory is developed for chain bonding fluids inside the critical region. Outside the critical region, the statistical associating fluid theory based on the first-order mean sphere approximation @Fluid Phase Equilibria 171, 27～2000 is adopted and all the microscopic parameters are taken directly from its earlier application of real fluids. Inside the critical region, the RG transformation for long-range density fluctuation is derived in the k space, which illustrates explicitly the contributions from the mean-field term, the local density fluctuation, and the nonlocal density fluctuation. The RG theory is applied to describe physical behavior of ten n alkanes (C1-C10) both near to and far from the critical point. With no additional parameters for chain bonding fluids, good results are obtained for critical specific heat and phase coexistence curves and the resulting critical exponents are in good agreement with the reported nonclassic values.