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Polymeric membranes are usually prepared from solvents like n-methylpyrrolidone (NMP) because of the strong dissolving power and high boiling point. Yet, the solvent is costly, toxic and has environmental issues. In this work, nontoxic solvents such as methyl l-lactate, ethyl lactate, propylene carbonate, tributyl o-acetylcitrate, tributyl citrate, triethyl phosphate, and γ-butyrolactone (GBL) were introduced during membrane preparation. It was found that all the solvents were unable to dissolve polyetherimide except GBL. The membranes made by GBL and NMP were evaluated for gas separation, and they have almost similar hydrogen-to-methane selectivity, but, hydrogen permeance was better in NMP membranes.

This study evaluated the effects of the pro-oxidant buthionine sulfoximine (BSO) and of the interaction between BSO and TETRAC, an antagonist of αvß3 integrin, on tumor development and aminopeptidase (AP) activity in a murine model of implanted Lewis's carcinoma. Male CBA-C57 mice were untreated (controls) or treated with BSO (222 mg/100 mL in drinking water), TETRAC (10 mg/kg/day, i.p.), or BSO + TETRAC. BSO for 28 days and TETRAC were given for the last 20 days. Mice were subcutaneously inoculated with 1 × 10(6) Lewis carcinoma 3LL cells into the dorsum. Study variables were tumor weight (TW); Hb, as index of tumor-mediated angiogenesis; vascular endothelial growth factor (VEGF) protein abundance; protein carbonyl content; α-tubulin abundance; and GluAp, AlaAp, and AspAp activities. BSO produced a major decrease in TW (203 ± 18 mg) with respect to controls (365 ± 26) and a reduction in Hb content. The TETRAC group also showed marked reductions in TW (129 ± 15) and Hb concentration associated with a reduced VEGF content. The BSO + TETRAC group showed a major TW reduction (125 ± 13); although, the difference with the TETRAC group was not significant. BSO treatment increased protein carbonyl and tubulin abundance in comparison to controls. The activity of all APs was increased in the three experimental groups and was strongly and negatively correlated with TW. In conclusion, administration of BSO reduced the TW, which inversely correlated with protein carbonyl content, suggesting a loss of microtubule polymerization. The finding of a negative correlation between TW and AP activity opens up new perspectives for the study of APs as tumor growth modulators.

The existence of acidic species other than those of vanadic acid is suggested to be responsible for the FCC catalyst deactivation. These species would come from SOs adsorption on the catalytic surface which would react with the most acid sites of the zeolite, ultimately leading to loss of crystallinity.