采用固体多核13C,27Al及29Si MAS NMR结合吸附气体Xe后的129Xe NMR,详细研究了乙烯和2-丁烯歧化生成丙烯反应过程中6%Mo/Hβ-Al2O3催化剂上积炭的类型和落位.结果表明,积炭以饱和烷烃为主,并随着反应的进行生成更多的支链烷烃,积炭主要...采用固体多核13C,27Al及29Si MAS NMR结合吸附气体Xe后的129Xe NMR,详细研究了乙烯和2-丁烯歧化生成丙烯反应过程中6%Mo/Hβ-Al2O3催化剂上积炭的类型和落位.结果表明,积炭以饱和烷烃为主,并随着反应的进行生成更多的支链烷烃,积炭主要分布在Hβ分子筛上,并主要落位在分子筛的交叉孔道处.展开更多
法国科学家伊夫·肖万(Yves Chauvin)和美国科学家罗伯特·格拉布(Robert H Grubbs)、理查德·施罗克(Richard R Schrock)3人因为发展了烯烃复分解反应在有机合成中的应用,而共享了2005年度的诺贝尔化学奖。简要介绍了烯烃...法国科学家伊夫·肖万(Yves Chauvin)和美国科学家罗伯特·格拉布(Robert H Grubbs)、理查德·施罗克(Richard R Schrock)3人因为发展了烯烃复分解反应在有机合成中的应用,而共享了2005年度的诺贝尔化学奖。简要介绍了烯烃复分解反应的原理、应用和发展简况,以及发现过程。展开更多
A series of novel calix[4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by ~1H NMR,^（13）C NMR and ESI-HRMS.Th...A series of novel calix[4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by ~1H NMR,^（13）C NMR and ESI-HRMS.Their complexation property towards cesium ion was studied by ^1H NMR technique.Two-phase extraction of alkali metal ions using UV-vis spectroscopy revealed remarkably different extractabilities.These results indicate that the complexation capacities towards cesium ions can be tuned and controlled through cooperative regulation of the strain of the loop and conformational change of calixcrown skelton.展开更多
文摘采用固体多核13C,27Al及29Si MAS NMR结合吸附气体Xe后的129Xe NMR,详细研究了乙烯和2-丁烯歧化生成丙烯反应过程中6%Mo/Hβ-Al2O3催化剂上积炭的类型和落位.结果表明,积炭以饱和烷烃为主,并随着反应的进行生成更多的支链烷烃,积炭主要分布在Hβ分子筛上,并主要落位在分子筛的交叉孔道处.
文摘法国科学家伊夫·肖万(Yves Chauvin)和美国科学家罗伯特·格拉布(Robert H Grubbs)、理查德·施罗克(Richard R Schrock)3人因为发展了烯烃复分解反应在有机合成中的应用,而共享了2005年度的诺贝尔化学奖。简要介绍了烯烃复分解反应的原理、应用和发展简况,以及发现过程。
基金financially supported by Institute of Nuclear Physics and Chemistry of CAEP(NoHG2008061)
文摘A series of novel calix[4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by ~1H NMR,^（13）C NMR and ESI-HRMS.Their complexation property towards cesium ion was studied by ^1H NMR technique.Two-phase extraction of alkali metal ions using UV-vis spectroscopy revealed remarkably different extractabilities.These results indicate that the complexation capacities towards cesium ions can be tuned and controlled through cooperative regulation of the strain of the loop and conformational change of calixcrown skelton.
