A novel process for preparing tin oxide thin films directly on copper foil by electrodeposition was developed. An optimal preparation technology to obtain SnOz thin films was proposed with current density of 8 mA/cm^2...A novel process for preparing tin oxide thin films directly on copper foil by electrodeposition was developed. An optimal preparation technology to obtain SnOz thin films was proposed with current density of 8 mA/cm^2, the time of deposition of 120 min, the concentration of tin dichloride of 0.02 mol/L and the concentration of dissociated acid of 0. 03 mol/L. The phase identification, microstructure and morphology of the thin films were investigated by thermogravimetric analysis and differential thermal analysis, X-ray diffraction, Fourier transform infrared spectra,scanning electron microscopy and transmission electron microscopy. The as-deposited thin film was composed of SnO2·xH2O was obtained by drying at room temperature. Nanocrystalline SnO2 thin film having tetragonal structure with average grain size in the range of 8 to 20 nm and porous, uniform surface was obtained by heat-treating the as-deposited film at 400 ℃ for 2 h. Electrochemical characterization shows that SnO2 film can deliver a discharge capacity of 798 mAh/g and the SnO2 film with smooth surface and annealed at 400 ℃ for 2 h has better cycle performance than that with rough surface and annealed at 150℃ for 10 h.展开更多
AIM: Smallanthus sonchifolius (Yacon) has been used as a food and folk medicine in the Andes region. It was screened the pharmacological effects of a 50% ethanol extract of Yacon on spermatogenesis in rats. This study...AIM: Smallanthus sonchifolius (Yacon) has been used as a food and folk medicine in the Andes region. It was screened the pharmacological effects of a 50% ethanol extract of Yacon on spermatogenesis in rats. This study is carried out to evaluate the possibility of using Yacon tubers extracts as a fertility agent to treat infertility caused by spermatogenic disorders. METHODS: The dried, pulverized Yacon tubers were extracted with 50% ethanol at 50 ℃ for 5 h under sonication. The Yacon extracts were analyzed by using HPLC system on a Kromasil C18 column (250 mm×4.6 mm). The Yacon tubers extracts, chlorogenic acid and ferulic acid were administrated to rats once daily by oral gavage. The number of sperm heads in the testis was assessed by counting the number of sperm heads using slight modification of the procedure reported by Toth et al (1989). RESULTS: After administration of chlorogenic acid and Yacon tuber extracts to rat for 5 weeks, the number of sperm in epididymis were increased by 20.33% and 34.48%, respectively. The ferulic acid which was reported as a metabolite of chlorogenic acid and constituent of Yacon to estimate the spermatogenic activity was also administered. After administration of ferulic acid and Yacon tubers extracts, the sperm number were increased by 37.87% and 43.33%, respectively. Spermatogenic effects of chlorogenic acid and ferulic acid were 0.59 times and 0.87 times of Yacon tubers extracts, respectively. CONCLUSION: The spermatogenic effect of Yacon tubers extracts may result from the combined effect of chlorogenic acid or its analogues and their metabolites.展开更多
文摘A novel process for preparing tin oxide thin films directly on copper foil by electrodeposition was developed. An optimal preparation technology to obtain SnOz thin films was proposed with current density of 8 mA/cm^2, the time of deposition of 120 min, the concentration of tin dichloride of 0.02 mol/L and the concentration of dissociated acid of 0. 03 mol/L. The phase identification, microstructure and morphology of the thin films were investigated by thermogravimetric analysis and differential thermal analysis, X-ray diffraction, Fourier transform infrared spectra,scanning electron microscopy and transmission electron microscopy. The as-deposited thin film was composed of SnO2·xH2O was obtained by drying at room temperature. Nanocrystalline SnO2 thin film having tetragonal structure with average grain size in the range of 8 to 20 nm and porous, uniform surface was obtained by heat-treating the as-deposited film at 400 ℃ for 2 h. Electrochemical characterization shows that SnO2 film can deliver a discharge capacity of 798 mAh/g and the SnO2 film with smooth surface and annealed at 400 ℃ for 2 h has better cycle performance than that with rough surface and annealed at 150℃ for 10 h.
文摘AIM: Smallanthus sonchifolius (Yacon) has been used as a food and folk medicine in the Andes region. It was screened the pharmacological effects of a 50% ethanol extract of Yacon on spermatogenesis in rats. This study is carried out to evaluate the possibility of using Yacon tubers extracts as a fertility agent to treat infertility caused by spermatogenic disorders. METHODS: The dried, pulverized Yacon tubers were extracted with 50% ethanol at 50 ℃ for 5 h under sonication. The Yacon extracts were analyzed by using HPLC system on a Kromasil C18 column (250 mm×4.6 mm). The Yacon tubers extracts, chlorogenic acid and ferulic acid were administrated to rats once daily by oral gavage. The number of sperm heads in the testis was assessed by counting the number of sperm heads using slight modification of the procedure reported by Toth et al (1989). RESULTS: After administration of chlorogenic acid and Yacon tuber extracts to rat for 5 weeks, the number of sperm in epididymis were increased by 20.33% and 34.48%, respectively. The ferulic acid which was reported as a metabolite of chlorogenic acid and constituent of Yacon to estimate the spermatogenic activity was also administered. After administration of ferulic acid and Yacon tubers extracts, the sperm number were increased by 37.87% and 43.33%, respectively. Spermatogenic effects of chlorogenic acid and ferulic acid were 0.59 times and 0.87 times of Yacon tubers extracts, respectively. CONCLUSION: The spermatogenic effect of Yacon tubers extracts may result from the combined effect of chlorogenic acid or its analogues and their metabolites.
