戊烯

Natural rubber which is cis 1,4 - polyisoprene is composed of isopentenyl pyrophosphate In Hevea brasiliensis.

巴西橡胶树中的天然橡胶是顺式-1，4-聚异戊二烯（cis-1，4-polyisoprene），其基本组成单元是异戊烯基焦磷酸(isopentenyl diphosphate ，IPP)。

The biosynthesis of the quinoid nucleus are the same in all coenzyme Qs. The biosynthesis of the isoprenoid side chain determine the kind of coenzyme Q.

芳香环的合成在所有的辅酶Q族物质中都是相同的，异戊烯基侧链的长度则决定了辅酶Q的种类，这里存在一个关键酶，即异戊烯焦磷酸合成酶。

The conversion of cyclyopentadiene reached 100%, and the selectivity to cyclyopentadiene was over 99%.

结果表明环戊二烯的转化率可达到100％，环戊烯的选择性和收率都达到99％以上。

In this paper, a series of 4,5-dithiacrown ether annulated 1,3-dithiole-2-thiones 8a~8d were prepared via condensing 4,5-bis-1,3-dithiole-2-thione (7) with 1,ω-dimercapto polyglycol derivatives in high dilution. The obvious template effect was found during the synthesis of 8c-8d.

在高度稀释条件下，经4，5-二溴甲基-1，3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1，ω-二巯基衍生物的缩合反应，方便地合成了4，5-位带二硫杂冠醚残基的2-硫代-1，3-二硫杂环戊烯的衍生物8a~8d，中间体硫杂冠醚8c~8d的合成中有明显的&模板效应&。

In this paper, a series of 4,5-dithiacrown ether annulated 1,3-dithiole-2-thiones 8a~8d were prepared via condensing 4,5-bis-1,3-dithiole-2-thione (7) with 1,ω-dimercapto polyglycol derivatives in high dilution. The obvious template effect was found during the synthesis of 8c-8d.

在高度稀释条件下，经4，5-二溴甲基-1，3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1，ω-二巰基衍生物的缩合反应，方便地合成了4，5-位带二硫杂冠醚残基的2-硫代-1，3-二硫杂环戊烯的衍生物8a~8d，中间体硫杂冠醚8c~8d的合成中有明显的&模板效应&。

Cyclopentenopyridine(3) in yield of 65% was synthesized from acrolein ,cyclopentanone and NH3 by heterogeneous catalysis reaction through a fixed bed reactor.

以丙烯醛和环戊酮为原料，用固定床多相催化法合成了2，3-环戊烯并吡啶，收率65%，含量高于50%。

From comparative research of synchronous and asynchronous reaction of dehydrogenation and cracking of dipentene,it is shown that farraginous extent of by-products from synchronous reaction is relatively high.

双戊烯脱氢裂解的同步反应和异步反应对比研究显示，双戊烯脱氢裂解的同步反应产物比较混杂，反应产物中甲苯的相对含量仅为24。

Selective hydrogenation for pentadiene in FCC C 5 fractions and hydroetherification of tertiary pentanes with methanol were investigated.

采用离子交换法制备了Pd/D0 0 5树脂催化剂，对催化裂化C5 馏分中戊二烯的选择性加氢和叔戊烯与甲醇的临氢醚化反应进行了研究。

A Pd /D005 resin catalyst was prepared by using ion exchangemethod.Selective hydrogenation for pentadiene in FCC C5 fractions and hydroetherification of tertiary pentanes with methanol were investigated.

采用离子交换法制备了Pd/D005树脂催化剂，对催化裂化C5馏分中戊二烯的选择性加氢和叔戊烯与甲醇的临氢醚化反应进行了研究。

A Pd /D005 resin catalyst was prepared by using ion exchange method.Selective hydrogenation for pentadiene in FCC C5 fractions and hydroetherification of tertiary pentanes with methanol were investigated.

摘 要：采用离子交换法制备了Pd/D005树脂催化剂，对催化裂化C5馏分中戊二烯的选择性加氢和叔戊烯与甲醇的临氢醚化反应进行了研究。

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。