Effect of microwave and He-Ne laser on enzyme activity and biophoton emission of Isatis indigotica fort

IEECAS SKLLQG

Influence of low doses microwave radiation on activities of antioxidative enzymes of Isatis indigotica seedlings exposed to enhanced UV-B radiation

IEECAS SKLLQG

Enhancement on the hydrothermal stability of ZSM-5 zeolites by the cooperation effect of exchanged lanthanum and phosphoric species

It was explored by density functional calculations that exchanged La or P species exert great influence on the local Al sites as well as on the adjacent exchanged species. In partially exchanged La- or P/H-ZSM-5 zeolite, some of the Al sites will fall off from the zeolite framework even more easily than in H-form ZSM-5, consistent with our XRF experiments. However, when exchanged by both La and P species, Al at either of the two exchanged sites shows better stability compared to H-from. zeolite. La and P species will interact strongly with each other, as evidenced by the charge donation process and the shortening of P-O-1 bond length. It was just the cooperation of La and P species that enabled RSCC catalysts worked normally under severe conditions. (C) 2004 Elsevier B.V. All rights reserved.

Hydrothermal synthesis and characterization of microporous crystals of trivalent metal-containing zirconium phosphates

Two organically templated trivalent metal-containing crystalline zirconium phosphate materials FeZrPO-8 and AlZrPO-8 have been prepared hydrothermally by using fluoride as a mineralizer, and 1,6-diaminohexane (DAH) as templates. The powder XRD patterns indicate that the as-synthesized products are new materials. Substitutions of Al3+ or Fe3+ into Zr4+ sites were confirmed by a combination of powder X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) studies. The thermal behavior of the title compounds have been investigated using TG-DTA and X-ray thermodiffractometry, which indicated that the inorganic framework of the compounds are thermally stable up to similar to400 degreesC. (C) 2004 Elsevier B.V. All rights reserved.