A correlation for estimation of the aqueous solubility of organic compounds that is based on a training set of 120 chemicals is proposed. The new model proposed is predictive and requires only molecular connectivity indices in the calculations. The calculated results of the new model are comparable to those from the existing general solubility equation (GSE) and the Klopman-Zhu models. The new model was also applied to a testing set of 80 compounds, and the predictions show that the new model is reliable with good predictive accuracy. Because the new model does not require any experimental physicochemical properties in the calculation, it is simple and easy to apply. This work shows again that molecular connectivity indices are useful structural descriptors in quantitative structure-property (QSPR) studies in pharmaceutical research.

An open-cell model equation of state has been proposed, which relaxes the restrictions of the cell theory and allows more flexibilities in describing the structure of liquids. To test its capability, this equation has been applied to a variety of liquids, including 17 heavy molecular weight hydrocarbons, 10 organic solvents, and 15 polymers, in particular. The calculated density grand average AADp for the equation proposed here are 0.062, 0.057, and 0.054 per cent against the results for the equation of state by Simha and Somcynsky, 0.081, 0.093, and 0.072 percent for the above three groups of liquids, respectively. Good agreement between our calculated results and experimental data indicates that our model is an improvement over the Simha and Somcynsky equation of state, which has been evaluated as one of the best equations. Moreover, this equation can be easily extended to describe the properties of polymer solutions and polymer blends, which will be addressed in our subsequent paper.

Aqueous liquefaction of Cunninghamia lanceolata, Fraxinus mandshurica, Pinus massoniana Lamb. and Populus tomentosa Carr. was carried out in an autoclave in the reaction temperature range of 553. 15-633. 15 K, where both non-catalytic and catalytic liquefaction were performed. The experimental results show that the lignin content has a large effect on the yield of liquefaction products in the noncatalytic liquefaction. The addition of K2CO3 as a catalyst can significantly reduce the residue yield for all the woods tested, while its effect on the heavy oil yield becomes weaker with decreasing amounts of lignin. The present study shows that a heavy oil yield of 30% coupled with a residue yield of less than 10% can be obtained for all the wood samples tested in the catalytic liquefaction.

A modified adjacency matrix was developed to delineate the chemical graph of a compound, in which the element aii along the diagonal of the matrix reflects the numbers of the lone-pair electrons and

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.