查询词典 olefins

The experiments for determining the reaction kinetics of Daqing atmospheric residue were performed in a continuous flow, expanded bed rector. Four-lumped reaction kinetic model was developed to account for various feed and product fractions of Daqing atmospheric residue (gases, gas oil, residue and coke). The amounts of olefins and alkyls in the gas products were further analyzed to determine reaction kinetics of gas product distributions. Hence, a combined five-lumped reaction kinetic model was obtained for catalytic pyrolysis of Daqing atmospheric residue. The kinetic constants both in four-lump model and five-lump model were evaluated. A simulator for catalytic pyrolysis process was developed by incorporating the five-lumped kinetic model into the hydrodynamic flow model.

其次利用改进的固定流化床装置考察大庆常压渣油催化裂解反应规律，筛选反应工艺参数；分析了催化裂解工艺存在的主要化学反应类型，提出了渣油一次反应和二次反应网络图；将反应原料油作为单独集总组分，而将产品中的轻质油、气体、焦炭分别作为集总，从而建立了四集总动力学模型；在此基础上，把气体产物中的目的产物低碳烯烃独立划分，得到五集总动力学模型；采用最小二乘法分析实验数据，分别得到四集总动力学模型和五集总动力学模型中各集总间相互反应转化的反应速率常数。

This novel reagent was treated with LDA to produce polystyrene-supported a-seleno carbanions, which reacted with alkyl halides and epoxides, followed by stereospecific selenoxide syn-elimination to give olefins and allylic alcohols respectively.

它与LDA反应形成α—硒基稳定的碳负离子，再与卤代烃或环氧化合物发生α—烷基化反应，烷基化后的树脂可以在30%的双氧水中进行氧化-消除，以良好产率和较高纯度合成了取代烯烃或烯丙基醇。

The C2 to C5 and heavier acetylenes and dienes in a thermally cracked feed stream are hydrogenated without significantly hydrogenating the C2 and C3 olefins.

使经过热裂解的进料物流中的C2－C5及更重的炔烃和二烯烃加氢，而不使C2和C3烯烃发生显著的加氢。

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。

They may also be converted to ethers and olefins.

醇又能转化为醚和烯烃。

The combination of these hydrides with some transition metal complexes exhibits high catalytic activity for the hydrogenation of olefins.

它们具有比一般市售碱金属氢化物高得多的反应活性，并能与过渡金属配合物组成高活性烯烃加氢催化。

This paper aimed as the separation of α-olefins from kerosine distillate of delayed-coking process and their application.

本文研究了采用尿素脱蜡工艺从延迟焦化柴油中分离出C〓-C〓的直链α烯烃和直链烷烃的工艺路线，其中采用异丙醇和水混合溶剂溶解尿素，与焦化柴油进行络合反应，这在文献中尚未见报导。

Urea adduction, in which i-propanol and water was used as mixed solvent, was introduced to separate α-olefins from coker kerosine distillate 220-320℃.

研究结果表明，采用异丙醇尿素水溶液脱蜡工艺，可从焦化柴油中成功分离得到直链α烯烃和直链烷烃，焦化柴油可作为C〓-C〓直链α烯烃与直链烷烃的一个重要来源。

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。