环烯

Propylene epoxidation to propylene epoxide is one of the most important challenges in catalysis because this reaction possesses both industrial significance and academic importance.

中文摘要：丙烯环氧化制环氧丙烷具有重大的工业应用背景和重要的学术意义，开拓该反应的高效催化体系和催化剂是催化领域的最重要的挑战之一。

Epoxidation of olefins is the most important reactions in organic synthesis to approach epoxides.

合成环氧化物的重要途径是烯烃的环氧化反应。

Epoxidation of olefins is one of the most important reactions in organic synthesis,because the epoxides can be easily converted to large variety of compounds.

烯烃环氧化反应是一类重要的有机反应类型，因为环氧化物是有机合成中重要的中间体。

The preparation of epoxides by reaction between alkyl peroxides and olefins catalyzed by high-valent transition metal complexes is one of the most important means of preparation of epoxides.

以高价过渡金属配合物为催化剂，催化烯烃直接环氧化反应是合成环氧化合物的重要途径之一。

The results available now indicate that glass-like carbon synthesized from phenolic resin is a non-graphitizing carbon, and consists of both sp 2-hybridized carbon atoms that form imperfect graphite structure and sp 3-hybridized carbon atoms that are due to the presence of disordered carbon; and in the fullerene-related structure of glass-like carbon, there exist some pentagons and heptagons carbon rings.

玻璃炭作为一种特殊炭材料已广泛应用于许多领域，其制备、性质、应用以及基本结构的研究已经取得了很大的进展，已有的研究结果表明酚醛树脂基玻璃炭是一种典型的非石墨化炭材料，由 sp2杂化态碳原子和 sp3杂态碳原子组成，且在其类富勒烯结构中存在五元环和七元环。

The coupling reaction of aryl iodides, bromides and chlorides with differentolefins catalyzed by catalyst 2 and 4 was studied. It was found that compounds 2 and 4 anchored on active carbon are efficient catalyst for the Heck reaction in the case of aryl bromides and aryl chlorides as substrates (Scheme 3). It is notable that catalyst 4 has higher efficiency for aryl chlorides.___^H Cat.2 or 4, Base HXSolution, 100C or 140

以化合物2和4为代表，重点研究了活性炭负载的二茂铁亚胺环钯化合物催化碘代苯、溴代苯和氯代苯与活泼烯烃之间的偶联反应(Scheme 3)，发现活性炭负载的二茂铁亚胺环钯化合物2和4均可用于催化多种溴代和氯

In the first part of this thesis, a formal [4+2] cycloaddition of ketenes with N-benzoyldiazenes catalyzed by chiral NHCs was studied, which gave 1,3,4-oxadiazin-6-ones in very high yields and enantioselectivites.

论文的第一部分内容是在手性氮杂环卡宾的催化下，烯酮与N-苯甲酰偶氮化合物的环加成反应，合成各种手性的噁二嗪酮，它们还可以经过简单的两步一锅法制备手性氨基酯。

A highly effective and efficient phosphorus-free, nitrogen-free and biodegradable sequestering agents and detergency builders Polyepoxysuccinic acid was synthesized through negative ion synthesis.

以顺丁烯二酸酐为原料，通过环氧化反应和阴离子聚合的方法，合成了一种无磷、非氮、生物降解性好的环保型阻垢剂聚环氧琥珀酸。

The cure kinetics of naphthyl/dicyclopentadiene epoxy resin and bis-phenoxy (3-hydroxy) phosphine oxide was investigated by differential scanning calorimetry under nonisothermal and isothermal condition.

用差示扫描量热仪研究了含萘环和二环戊二烯环结构环氧树脂NDEP和BHPPO的等温和非等温固化动力学。

Many other reactions catalyzed by phosphines have also been studied.

进而用2，3-联烯酸叔丁酯来研究[3+2]环加成反应合成螺环化合物，区域选择性有很大提高，产率也很好。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。