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胺类、氮杂环的N-烷基化和硫醇的S-烷基化
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作者 moghaddam FM 张绍静(摘) 《中国医药工业杂志》 CAS CSCD 北大核心 2008年第5期327-327,共1页
胺类、酰胺类、氮杂环或硫醇的乙腈溶液中,加入KF/碱性氧化铝,回流搅拌20min,冷至室温,加入卤代烷,回流反应1~2.5h,得到相应的N-烷基化产物,13例收率54%~95%,或S-烷基化产物,12例收率73%~93%。
关键词 酰胺类 氮杂环 S-烷基化 N-烷基化 硫醇 烷基化产物 回流反应 乙腈溶液
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Energy budget and economic analysis in conventional and organic rice production systems and organic scenarios in the transition period in Iran
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作者 Hamed MANSOORI Parviz Rezvani +1 位作者 moghaddam Rooholla MORADI 《Frontiers in Energy》 CSCD 2012年第4期341-350,共10页
Compared to conventional agriculture, organic agriculture is reported to be more efficient and effective in reducing water and soil pollution, greenhouse gases (GHGs) emission and risk of human health. In additional... Compared to conventional agriculture, organic agriculture is reported to be more efficient and effective in reducing water and soil pollution, greenhouse gases (GHGs) emission and risk of human health. In additional, field management under organic condition can be useful for increasing energy efficiency. Rice is one of the important crops which are cultivated in two forms, organic and conventional, in Iran. In order to compare the energy efficiency and economic analysis of rice production in organic and conventional systems in Iran, needed informa- tion was collected by face-to-face questionnaire in 2011 and three scenarios were designed to predict the changes of energy budget and economic analysis in the transition period that included: 25%, 50% and 75% organic management in rice production. The results showed that all energy indexes were improved in organic rice production compared to conventional condition. Higher values of benefit to cost ratio, gross and net return and lower value of total cost of production were obtained from organic rice production which indicated that the organic management of farm improved economically in compar- ison with the conventional rice production system. The shares of direct and renewable energies were increased by approach to organic management. Increase in energy efficiency and productivity was predicted for the transition period but decrease trend in economic indexes was projected for this period in all scenarios. The main reason for decreasing economic indexes in organic scenarios was that the market price of organic rice was the same as that of conventional rice in the transition period. 展开更多
关键词 energy efficiency specific energy net return Cobb-Douglas function
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