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A sol-gel route to synthesize nanocrystalline praseodymium-, samarium- and gadolinium-doped ceria powders for solid oxides fuel Cells SOFCs is presented. The method involves metal nitrates with propionic acid (both as chelating ligand and solvent), gel formation, liquid nitrogen quenching, drying at 150 °C/24 h, and finally decomposition at 450 °C in nitrogen followed by calcination at 650 °C in air. TG-DTA, BET, XRD, FTIR, UV-vis and catalytic tests were used to characterize the samples. CePrO sample exhibited the best catalytic performance in methane steam reforming under water deficient conditions, closely followed by CeGdO, CeSmO and CeGdO catalysts. The superior catalytic performance of CePrO sample was attributed to the existence of praseodymium species (Pr/Pr) strongly interacting with ceria. The two systems act synergistically in the catalytic steam reforming of methane. [ABSTRACT FROM AUTHOR]

Compares the benefits between highly purified follicle-stimulating hormone (H.P. FSH) and human menopausal gonadotrophin (hMG) for ovarian hyperstimulation in women aged 37-41 years. Procedures of hormonal treatment; Difference regarding fertilization rates per oocyte retrieved; Implantation rates of each groups; Efficacy of H.P. FSH over hMG.

Presents a study of the prognostic factors of in vitro fertilization outcome in women with elevated follicle-stimulating hormone (FSH) levels. Effect of a combination of gonadotropin-releasing hormone agonist/human menopausal gonadotropin on FSH level; Pregnancy rates of patients with growing follicles during stimulation.