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971.
Distribution of samarium and ytterbium in rats measured by enriched stable isotope tracer technique and INAA 总被引:2,自引:0,他引:2
Fuliang Li Yuqi Wang Zhiyong Zhang Jingxin Sun Haiqing Xiao Zhifang Chai 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(3):437-441
In the present study a method using enriched stable isotope tracer and instrumental neutron activation analysis (INAA) was developed to study the dynamic distribution of rare earth elements (REEs) in a variety of organs and tissues of Wistar rats. Stable isotopes 152Sm and 168Yb were selected as tracers for the experiment. Intravenously injected 152Sm and 168Yb in chloride form could be quickly absorbed and distributed in almost all the organs and tissues of interest, including liver, skeleton, kidney, spleen, heart, lung, testicle, and blood serum. Liver and skeleton had high ability to take up 152Sm and 168Yb under the experimental conditions, whereas the contents of the elements in other organs were generally lower than 2% of the given dose during the whole experimental period. The difference in distribution of 152Sm and 168Yb in the body was also discussed. 相似文献
972.
Jingsong Sun Lin Liang Jianmin Sun Yanqiu Jiang Kaifeng Lin Xianzhu Xu Runwei Wang 《Catalysis Surveys from Asia》2011,15(1):49-54
This short review presents the recent developments in the direct synthesis of cyclic carbonates from olefins and CO2. The straightforward synthesis of cyclic carbonates from olefins instead of epoxides, also called one-pot “oxidative carboxylation”
of olefins, can be viewed as the coupling of two sequential reactions of epoxidation of olefins and CO2 cycloaddition to epoxides formed. The facile synthetic approach would make carbonate synthesis simpler and even cheaper with
industrial potential from environmental and economic points of view. Some progresses have been made on this direct synthetic
reaction for cyclic carbonates with homogeneous and heterogeneous catalysts, however, this reaction system is still at a preliminary
stage. Among the catalysts reported, only a few can be considered as effective for the direct oxidative carboxylation of olefins
to cyclic carbonates. Thus active and selective catalysts should be explored to put the direct synthesis of cyclic carbonates
into practical applications. 相似文献
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