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Nonionic water soluble complex Ru 3(CO) 9(PETPP) 3 with the function of thermoregulated phase transfer catalysis was prepared. The catalytic activity and the recycle effect of Ru 3(CO) 9(PETPP) 3 for hydrogenation of styrene in aqueous/organic biphase catalysis system were studied. In addition, effects of reaction temperature, hydrogen pressure and reaction time were also investigated. The results showed that the reaction takes place mainly in organic phase at higher temperature (80 ℃). Under the conditions of θ =80 ℃, p (H 2)=2 MPa and t =3 h, both the PhCH∶CH 2 conversion and PhC 2H 5 selectivity are 100%. The PhCH∶CH 2 conversion is still 98 2% after reuse of the catalyst for 20 times. The catalytic performance of Ru 3(CO) 9(TPPTS) 3, Ru 3(CO) 9(PETPP) 3, Ru 3(CO) 9(TPPMS) 3 and Ru 3(CO) 9(TPP) 3 for biphase hydrogenation of styrene was compared. The experimental results for Ru 3(CO) 9(PETPP) 3 verified that there is a thermoregulated phase transfer catalysis process in the reaction system. 相似文献
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甲醇水蒸气重整制氢Pd/ZnO催化剂的研究 总被引：3，自引：2，他引：3
采用并流共沉淀法制备Pd／ZnO甲醇水蒸气重整制氢催化剂,考察了Pd的质量分数和还原温度对催化剂性能的影响。结果表明,当Pd质量分数为15．9％,还原温度为573K时,催化剂有较好的甲醇转化率及二氧化碳选择性。TPR结果表明,PdO在室温下被还原为金属Pd,在440K开始有部分ZnO被还原。XRD分析结果表明,PdZn合金是甲醇水蒸气重整反应的活性中心;在21．9％Pd／ZnO催化剂上出现了Pd2Zn合金相,导致催化剂的活性下降;反应过程中还原催化剂形成PdZn合金,其活性不如相同条件下纯氢还原的。15．9％Pd／ZnO催化剂及工业铜基催化剂的初始稳定性结果显示,在8h内,15．9％Pd／ZnO催化剂上甲醇转化率保持在66％以上,而铜基催化剂的活性下降了14．4％。 相似文献
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21世纪,将是世界科学技术快速发展的时代,也是人才竞争的时代,因而也必将是人类智力突飞猛进的发展时期。世纪的未来主人,正是今天朝气蓬勃的儿童。如何使他们的智力得到开发,成为时代的优秀人才,是我们广大教育工作者义不容辞的责任,特别是对我们担负幼儿教育的一线教师来说,更是一个神圣 相似文献
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数字音频矩阵是广播电台广播中心技术的数字化、网络化核心枝术系统、了解数字音频矩阵的性能与使用在数字化设备改造过程中非常重要。 相似文献
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