An interesting two-stage adsorption mechanism, defined as “ideal adsorption” and “insertion adsorption”, was first proposed for the benzene/HY system by Metropolic Monte Carlo simulations at loadings below and above an “inflection point”.

Monte Carlo (MC) simulations were performed to study the influence of framework protons on the adsorption sites of the benzene molecule in HY zeolite with different Si:Al ratios. Eleven types of adsorption sites were observed including five reported sites (H1, H2, U4, U4­(H1), and W) and six newfound sites (W­(2H1), U4­(2H1), H1­(H2), U4­(H1,H1), H1­(H2,H1), and U4­(H1,H1,H1)), which were “supersites” with more than one proton. The stability order of the sites found in the 28Al model can be expressed as U4­(H1,H1,H1) > U4­(H1) > H1­(H2,H1) > W­(2H1) > U4­(H1,H1) > H1­(H2) > H1 > H2 > U4 > U4­(2H1) > W. Increasing number of zeolite protons resulted in an increasing proportion of supersites, which enhanced adsorption energies of sites. For HY zeolite models containing different numbers of protons with the same ratio of H1:H2, the amount of the most stable adsorption sites containing H1 proton increased, while the amount of the most stable adsorption sites containing H2 decreased, with increasing number of protons.

The effects of 18 different amino acid based ionic liquids (AAILs) on the phase behavior of an acetonitrile + water mixture were predicted through the COSMO-RS method, indicating that all investigated AAILs could enhance the relative volatility of acetonitrile and break the azeotrope, in which 1-ethyl-3-methylimidazolium proline ([EMIM][Pro]) was the most effective at a given condition. Furthermore, the properties of the interaction energy, charge-density profiles, and excess enthalpy were obtained, showing that the stronger interactions between AAIL and water lead to improvement of the separation efficiency. To verify the feasibility, the isobaric vapor−liquid equilibrium data for two ternary mixtures of acetonitrile + water + [EMIM][Pro] and + 1-ethyl-3-methylimidazolium acetate ([EMIM][OAC]) at fixed IL mole fraction (0.05 and 0.10) were measured at atmospheric pressure. The experimental results show that the two ILs can effectively enhance the relative volatility of acetonitrile and break the azeotrope at the mole fraction 0.05 and the higher the IL content in the mixture, the better the separation effect observed.

Porous fillers are considered as an effective way to improve the mechanical properties of dental composites through the interlocking with organic matrix. In this paper, mesoporous silica (mobil crystalline materials-41) of different particle sizes was synthesized, modified, and added in bisphenol-A glycidyl dimethacrylate/triethylene glycol dimethacrylate resins to obtain composites at different loading levels. The influence of mesoporous filler concentration, particle size, and surface modification on the mechanical properties (flexural strength, flexural modulus, and Vickers microhardness) of composites has been investigated in detail. Compared to nonporous silica, mesoporous silica significantly improved composites' mechanical properties. Flexural strength and flexural modulus are increased by 44.5% and 33.4%, respectively, when filler mass fraction reaches 15 wt%. Samples filled with silane-modified mesoporous silica show a higher flexural strength with the particle size decreasing from around 470 to 35 nm. The results implied potential applications for dental composites filled with porous fillers.