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A modified gas-translation (GT) model was applied for the theoretical analysis of gas permeation through microporous organosilica membranes derived from bis(triethoxysilyl)ethane (BTESE) via a sol-gel method using different water/alkoxide molar ratios. The pore sizes of BTESE-derived membranes were quantitatively determined by normalized Knudsen-based permeance analysis, which was based on a modified-GT model, using experimentally obtained permeances of He, H 2 , N 2 , C 3 H 8 , and SF 6 . The pore sizes of BTESE-derived membranes were successfully controlled from 0.65 to 0.46 nm by increasing the H 2 O/BTESE ratio from 6 to 240. Furthermore, theoretical correlations of all possible pairs of permeance ratios were calculated based on the modified-GT model. The experimental data were in good agreement with the theoretical correlation curves, indicating that the modified-GT model can clearly explain gas permeation mechanisms through microporous membranes, and, thus, can be used to predict the gas permeation properties for these membranes.

The dehydrogenation of methylcyclohexane (MCH) to toluene (TOL) for hydrogen production was theoretically and experimentally investigated in a bimodal catalytic membrane reactor (CMR), that combined Pt/Al 2 O 3 catalysts with a hydrogen-selective organosilica membrane prepared via sol-gel processing using bis(triethoxysilyl) ethane (BTESE). Effects of operating conditions on the membrane reactor performance were systematically investigated, and the experimental results were in good agreement with those calculated by a simulation model with a fitted catalyst loading. With H 2 extraction from the reaction stream to the permeate stream, MCH conversion at 250 C was significantly increased beyond the equilibrium conversion of 0.44-0.86. Because of the high H 2 selectivity and permeance of BTESE-derived membranes, a H 2 flow with purity higher than 99.8% was obtained in the permeate stream, and the H 2 recovery ratio reached 0.99 in a pressurized reactor. A system that combined the CMR with a fixed-bed prereactor was proposed for MCH dehydrogenation.

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Organosilica microporous membranes were fabricated from 1, 2-bis (triethoxysilyl) ethane (BTESE)-derived sols prepared in acidic pH via the pH-swing method. This method includes two steps whereby a specific amount of NH 3 was added into the acid sols and switched to acid after a reaction of several minutes. We found that the size of the BTESE-derived sols by pH-swing could be controlled via the H 2 O/BTESE molar ratio and the reaction time in alkali. Under the same H 2 O/BTESE ratio of 60, the BTESE-derived sols prepared in the pH-swing method showed an increase sol size in contrast with the acid method, and the sol size was easily controlled by the dominating reaction in alkali pH-the condensation reaction. Gas permeation results showed that some gases (He, H 2 , N 2 , C 3 H 8 , SF 6) permeated the membrane that was prepared using the pH-swing sols (pH-swing membrane) at approximately twice the rate shown by the membrane prepared using acid sols (acid membrane); H 2

The effectiveness of the electronic parameter on the predicting the mechanical properties of Zn system alloys for high temperature applications was evaluated in order to satisfy both the tensile strength of 200 MPa and elongation of 5%. The electronic parameter was used s-orbital energy level (ΔMk) in this study. Promising composition of alloys were Zn-4Al-7Sn, Zn-10Al-0.5Sn, Zn-10Al-2Sn and Zn-5.1Al-0.5Sn in mass%, and their ΔMk values were 0.079, 0.080, 0.089 and 0.045, respectively. The experimental results of tensile test for designed alloys showed that the tensile strength of 195-225 MPa depend on the increment of ΔMk values, and elongation are 4.5-5.1%. Optimization of composition on Zn system alloys was found to be speedy and precisely achieved using the ΔMk parameter. The wetting contact angles between Cu plate and the designed alloys of Zn-4Al-7Sn, Zn-10Al-0.5Sn, Zn-10Al-2Sn and Zn-5.1Al-0.5Sn at 973 K in the Ar stream are 33.8 , 43.3 , 50.1 and 44.3 , respectively, suggesting that the designed alloys can be practically applied at high temperature. Moreover, the thermal conductivity, tensile test of designed alloys at high temperature were also evaluated.

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