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Steam CO 2 reforming of methane was carried out over cerium substituted perovskite catalysts. Among the catalysts studied, La 0.9 Ce 0.1 NiO 3 showed the best performance with 49% of methane and 14% of CO 2 conversion under the tested conditions. The chemical and structural properties of the catalysts before and after the reaction were studied by N 2 physisorption, X-ray diffraction, CO 2 -TPD, TPH, TPR, TGA and TEM. It was found that most of Ce existed as CeO 2 rather than being incorporated in perovskite lattice because of large difference in ionic radii between La 3+ and Ce 4+ . Few substitution of Ce in A site resulted in high degree of reduction for active Ni species with good catalytic activity which was further decreased with increasing Ce concentration; substitution of large amount of Ce species led to methanation of CO 2 and formation of large nickel cluster. TPH and TGA analysis revealed that Ce substituted catalyst has better resistance to coke deposition compared to non-promoted perovskite catalyst. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Patrinia scabiosaefolia Fisch is used in folk medicines to treat intestinal abscesses, acute appendicitis, and dysentery in Asia. Although recent reports indicate that Patrinia scabiosaefolia has sedative and anti-tumor effects, its effects on ulcerative colitis have not been previously explored. Aim of the study: To determine the effects and the mode of action of the methanol extract of the roots of Patrinia scabiosaefolia (PME) on a model of colitis in mice induced by dextran sulfate sodium (DSS). Materials and methods: We induced colitis using DSS in 5-week-ICR mice over 7 days and estimated disease activity index (DAI), which took into account body weight, stool consistency, gross bleeding, and tissue myeloperoxidase (MPO) accumulation. Colon lengths and spleen weights were measured. Histological changes were observed by H&E staining. Pro-inflammatory mediators, namely, nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), were determined using Griess assays, immunoassays, and by quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR), respectively. Results: PME significantly attenuated DSS-induced DAI scores and tissue MPO accumulation, which implied that it suppressed weight loss, diarrhea, gross bleeding, and the infiltrations of immune cells. PME administration also effectively and dose-dependently prevented shortening of colon length and enlargement of spleen size. Histological examinations indicated that PME suppressed edema, mucosal damage, and the loss of crypts induced by DSS. Furthermore, PME inhibited the abnormal secretions and mRNA expressions of pro-inflammatory cytokines, such as, TNF-α, IL-1β, and IL-6. Conclusion: These results suggest that PME has an anti-inflammatory effect at colorectal sites that is due to the down-regulations of the productions and expressions of inflammatory mediators, and that it may have therapeutic value in the setting of inflammatory bowel disease (IBD). [Copyright &y& Elsevier]

Steam reforming of methane (SRM) was performed over a mixed Ni/MgAl + CrFe 3 O 4 catalyst. The catalyst was prepared by physical mixing method and it was compared to Ni/MgAl and iron or chromium promoted M/Ni/MgAl catalysts prepared by impregnation method. Catalysts were characterized by various analytical techniques such as nitrogen physisorption, TPR, XRD, TGA and SEM. The catalytic activity in a fixed-bed reactor was investigated at a temperature range of 500–700 °C, 1 bar pressure and feed molar ratio of H 2 O/CH 4 = 2. TPR and XRD illustrated that segregated Ni particles were observed with promoted M-Ni/MgAl catalysts and it leads to reduce the active Ni metal. The addition of the Cr/Fe 3 O 4 catalyst activates steam and easily reacts with methane. Consequently, physically mixed catalysts showed higher hydrogen selectivity and methane conversion than the other catalysts. [ABSTRACT FROM AUTHOR]