Deactivation mechanism of Cr-Al2O3catalyst and the interaction of Cr-A1 in the dehydrogenation of isobutane, as well as the nature of the catalytic active center, were studied using XRD, SEM, XPS, H2-TPR, isobutane-TP...Deactivation mechanism of Cr-Al2O3catalyst and the interaction of Cr-A1 in the dehydrogenation of isobutane, as well as the nature of the catalytic active center, were studied using XRD, SEM, XPS, H2-TPR, isobutane-TPR and TPO techniques. The results revealed that the deactivation of Cr-Al2O3 catalyst was mainly caused by carbon deposition on its surface. The Cr3＋ ion could not be reduced by hydrogen but could be reduced to Cr2＋ by hydrocarbons and monoxide carbon. The active center for isobutane dehydrogenation could be Cr2＋/Cr3＋ produced from Cr6＋ by the on line reduction of hydrocarbon and carbon monoxide. The binding energy of Al3＋ was strongly affected by the state of chromium cations in the catalysts.展开更多
The present objective is to observe the side effects and complications of fem ale tubalsterilization by phenol-atabrinepaste (PAP) and phenolm ucilage (PM). 1 705 eligible w om en w ere divided random ly into tw o g...The present objective is to observe the side effects and complications of fem ale tubalsterilization by phenol-atabrinepaste (PAP) and phenolm ucilage (PM). 1 705 eligible w om en w ere divided random ly into tw o groups, 871 usinig PAP and 834 w om en using PM. Results: Thefeverratesw ere8.0and 4.4( P< 0.01 ) respec- tively in group PAP and group PM. Infection rates of the appendages w ere 2.3 and 1.2 respectively. The incidence of chem ical peritonitis, w ithin the lim its of pelvic cavity, w ere 1.1and 2.4respectively. Perforation of uterus, pelvic ab- scessand ectopicpregnancy w ere notfound during thisobservation. Slightabdom inal pain after the proceduresw ere 33.6and 30.8respectively. Slightvaginalbleed- ing after the procedure w as 23.2 and 18.0 respectively. Menstruation of the w om en w as not affected by the instillation. This five-year follow -up study neither show ed a positivePap testnor a potentialdeseasecaused by thesterilizing agents. This technique isa safe and efficientm ethod for fem ale sterilization.展开更多
基金supported by the Natural Science Foundation of Shandong Provence of China(ZR2013BM008)
文摘Deactivation mechanism of Cr-Al2O3catalyst and the interaction of Cr-A1 in the dehydrogenation of isobutane, as well as the nature of the catalytic active center, were studied using XRD, SEM, XPS, H2-TPR, isobutane-TPR and TPO techniques. The results revealed that the deactivation of Cr-Al2O3 catalyst was mainly caused by carbon deposition on its surface. The Cr3＋ ion could not be reduced by hydrogen but could be reduced to Cr2＋ by hydrocarbons and monoxide carbon. The active center for isobutane dehydrogenation could be Cr2＋/Cr3＋ produced from Cr6＋ by the on line reduction of hydrocarbon and carbon monoxide. The binding energy of Al3＋ was strongly affected by the state of chromium cations in the catalysts.
文摘The present objective is to observe the side effects and complications of fem ale tubalsterilization by phenol-atabrinepaste (PAP) and phenolm ucilage (PM). 1 705 eligible w om en w ere divided random ly into tw o groups, 871 usinig PAP and 834 w om en using PM. Results: Thefeverratesw ere8.0and 4.4( P< 0.01 ) respec- tively in group PAP and group PM. Infection rates of the appendages w ere 2.3 and 1.2 respectively. The incidence of chem ical peritonitis, w ithin the lim its of pelvic cavity, w ere 1.1and 2.4respectively. Perforation of uterus, pelvic ab- scessand ectopicpregnancy w ere notfound during thisobservation. Slightabdom inal pain after the proceduresw ere 33.6and 30.8respectively. Slightvaginalbleed- ing after the procedure w as 23.2 and 18.0 respectively. Menstruation of the w om en w as not affected by the instillation. This five-year follow -up study neither show ed a positivePap testnor a potentialdeseasecaused by thesterilizing agents. This technique isa safe and efficientm ethod for fem ale sterilization.
