查询词典 olefins

Based on the results and discussion of those experiments, a adoptable utilization method of the α-olefins were given

对于从焦化柴油分离得到的直链α烯烃的利用，特别是作为化工合成原料的利用，还没有人进行过比较深入的研究。

In addition, the effect of different olefins on alkylation reaction was also investigated.

另外，还考察了烯烃碳链长度对苯烷基化反应的影响。

The alkylation of benzene with long-chain olefins has been performed in the presence of ionic liquid, the reaction conditions are optimized.

研究了离子液体催化苯与烯烃的烷基化，考察了反应条件对烷基化反应的影响。

Fischer et al.in 1973. Since these compounds have various particular reactions in organic synthesis,especially in vitamins,peptides,synthesis of anti-cancer drugs and natural products,and as olefins, alkyne polymerization catalysts demonstrated its unique advantages and broad application prospects.

由于这类化合物有各种奇特的反应性能，在有机合成中，尤其是在维生素，多肽，抗癌药物和天然产物的合成，和作为烯烃，炔烃聚合催化剂方面显示出其独特的优越性和广阔的应用前景。

In particular, the production of propylene and other important olefins via olefins metathesis reaction from n -butenes feedstock has received considerable attention.

特别是在利用正丁烯生产丙烯和其它重要单烯烃方面，复分解反应受到越来越多的重视。

The effect of zeolites ion-exchanged by transition metals on thermal catalytic cracking reaction is studied. The product distributions of the cracking reactions catalyzed by theβor ZSM-5 zeolites exchanged with transition metals are different from that catalyzed by corresponding Hzeolites, which means the mechanism of cracking reactions has varied. Group Ⅷ metals Fe, Co, Ni and Cu, Zn are shown to be of strong catalytic activity of oxidative dehydrogenation, while Ti and Cr are not of oxidative activity. Catalyzed by zeolites or catalyst containing Ag, conversion of thermal catalytic cracking reactions and the yield of ethylene increase while the yield of propylene does not decrease. Silver can not only promote the formation of carbonium ion, but also convert carbonium ion into free-radical via redox reaction. The weak adsorption of olefins on silver reduces the occurrence of hydrogen transfer and dehydrogenation. As a result, the yield of light olefins is favored by silver in the catalyst.

采用过渡金属交换的分子筛作为催化剂，进行催化热裂解制取乙烯的反应，研究发现，在β沸石分子筛和ZSM-5分子筛中引入过渡金属后，催化热裂解反应的产物分布与相应的氢型分子筛相比有了较大的变化，说明过渡金属的加入对于催化热裂解反应的机理具有影响，Ⅷ族金属如Fe、Co、Ni和第Ⅰ、Ⅱ副族Cu、Zn表现出较强的氧化脱氢活性，产物中氢气、焦炭的产率很高，Ti、Cr则未表现出氧化作用：分子筛及催化剂中引入银后，催化热裂解反应的转化率和乙烯的产率有了提高，丙烯产率没有很大的变化，说明银在催化热裂解反应中能够促进正碳离子的生成，又有可能通过氧化-还原作用部分改变反应机理，促进了自由基的生成，并且由于银对烯烃的吸附很弱，其氢转移反应和脱氢、加氢活性比较低，有利于烯烃产率的提高。

The catalytic cracking of NNJ 150 over USHY, HZSM 5 and SAPO 34 catalysts presented as that the selectivity of light olefins over USHY was the lightest among the three calalysts with a quicker deactivation, while HZSM 5 showed a longer catalyst life and lower selectivity of light olefins, for SAPO 34, both the conversion and the selectivity of light olefins were the lowest.

实现吸热型碳氢燃料这种功能的关键之一是选择适当的化学反应。由于碳氢燃料的裂化是吸热反应，而催化裂化与热裂化相比，能降低反应的温度，因此催化裂化是实现吸热型碳氢燃料功能较好的途径之一。由热力学可知，燃料裂化生成乙烯、丙

Molybdophopsphoric Acid Catalysis in the Oxidative Cleavage of Olefins by the Hydrogen Peroxide Oxidative cleavage of the double bond could be catalyzed by H_3PMo_(12)O_(40) using H_2O_2 as oxidant, various trisubstituted olefins were oxidized to aldehydes or ketones in high yields. The system was not satisfied for electron-deficient olefins such as trans-(2-nitrovinyl) benzol or chalcone. The reaction of aliphatic olefins did not occur under the same conditions.

二、磷钼酸催化过氧化氢对烯烃的氧化断裂反应用过氧化氢(30％)作为氧化剂，磷钼酸可以催化氧化碳碳双键的断裂反应，三取代的烯烃被氧化生成醛或酮，产率较高；此体系对于缺电子烯烃如查尔酮，不饱和硝基化合物的断裂反应效果较差，脂肪族烯烃在此体系下的氧化并不发生。

Herein the latest developments of olefin aqueous polymerization which are mainly promoted by late- transition metal catalysts are reviewed including ethylene,α-olefins, cyclo-olefins and dienes polymerization, along with ROMP of cyclo-olefins and CO/olefins copolymerization.

本文综述了后过渡金属催化剂水相催化烯烃配位聚合的一些新进展，内容包括烯、α-烯烃、环烯烃、二烯烃的聚合反应和环烯烃的开环聚合反应以及CO/烯烃的共聚反应等方面。

However, there is little work reported on the separation ofα-olefins and other internal olefins.

对于不同烯烃之间的分离，特别是沸点相近的同分异构体烯烃之间的分离，国内外报道均不多。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。