双烯

Di-cyclopentadiene deserves to be mentioned for its simple decomposed product,cyclopentadiene,and its low-price.

尤其是双环戊二烯的分解产物单纯，仅有解聚后的环戊二烯一种，且价廉、易得，值得重视。

To enable the fabrication of a thermally stable ultralow dielectric constant film, specific precursor materials are used, such as, silane derivatives, for instance, diethoxymethylsilane and organic molecules, for instance, bicycloheptadiene and cyclopentene oxide.

为了制造热稳定的超低介电常数膜，使用特殊的前体材料，如硅烷衍生物例如二乙氧基甲基硅烷和有机分子例如双环庚二烯和环戊烯氧化物。

P-Isopropylphenol was synthesized by catalytic transfer dehydrogenation with 5% Pd/C using 4-isopropylcyclohexenone as the material and the hydrogen offer, industrial dipentene as the hydrogen acceptor and the solvent.

采用5%Pd/C作为转移氢催化剂，4-异丙基环己烯酮为氢给予剂，工业双戊烯为氢接受剂和溶剂进行反应，合成了对异丙基苯酚。

Methodologies for stereoselective synthesis of alkenes are of great interest in synthetic organic chemistry since many biologically active compounds occuring in nature possess the structural skeleton of disubstituted or trisubstituted alkenes.

烯烃的立体选择合成方法学研究是有机合成化学中的重要课题，因为许多重要的天然产物中均含有双取代或三取代烯烃的结构单元。

Other methyl nucleophiles includingMeMgBr, MeCeCl2, MeTiCl3, Me3Al, Me3ZnMgCl, MeMnClwere tried, but in all these cases no detectable amount of exo-C8-methylated product was obtained. Although protecting C3-carbonyl as 1,3-dioxolanes could be achieved, the serious enolization of C8-carbonyl was still problematic. Converting C9-furan ring to α,β-butenolide did depress the enolization, but desired C8-methylation was completely replaced by migration of the double bond of the butenolide.

在本论文的早期阶段，主要着眼于解决二环[3.2.1]-C8-羰基加成甲基所遇到的C9-呋喃环差向异构化和C3与C8两个羰基之间化学选择性的问题：通过引入不同金属降低甲基试剂的碱性并没有取得甲基化的成功；通过不同的方法将C3-羰基掩蔽，但是C8-羰基的烯醇化依然无法抑制；虽然通过将呋喃环转化为α，β-不饱和-γ-丁内酯可以抑制烯醇化，但内酯环上的双键迁移又成了新的竞争反应。

In the synthesis of canthaxanthin by selective catalylitic oxidating of βcarotene,CO2 was used as acidifying or alkalizing agent,which controlled reacting system acidity and protected polyene.,producing less by-products and increasing catalylitic oxidation selectivity.In the addition reaction of isoprene with hypochloric acid,1-chloro-2-methyl-3-buten-2-ol and l-chloro-2-methyl-3-buten-4-ol were made by controlling of the acidity with carbon dioxide i...

CO2作为酸碱调节剂和惰性气体，在β-胡萝卜素催化氧化合成角黄素反应中，可以控制反应体系酸性，保护原料中的双键，减少副反应发生，提高催化氧化反应的选择性；异戊二烯氯醇化生成1-氯-2-甲基-3-丁烯-2-醇和1-氯-2-甲基-3-丁唏-4-醇反应中，CO2代替有机酸作酸碱调节剂，控制次氯酸的生成速度，达到调控反应的目的，反应条件温和，不副产固体。

The volatile components were separated and identified using GC-MS technique. RESULTS Seven ingredients were. isolated: 2-ethyl-hexyl-adipate (66.5%), 1-methoxy-4-(1-propenyl)benzene (12.5%), isopropyl isothiocyanate (6%), isobutylisothiocyanate (6%), 6-methyl-5-heptene-2-one (3.5%), benzaldehyde (1.4%), phenylacetaldehyde (0.8%).

结果 分离出7个成分，采用峰面积归一化法确定了各成分的相对含量，分别为66.5%双－2-乙基己基－己二酸、12.5%1-甲氧基－4-（1-丙烯基）苯、6%异硫氰酸异丙酯6%、6%异硫氰酸异丁酯、3.5%6-甲基－5-庚烯－2-酮、1.4%苯甲醛、0.8%苯乙醛。

A similar reaction of the sulfur analog gave only the product of tetramethylene bridged bisdititanium halides.

在企图合成硫桥环戊二烯基化合物时，得到的却是四亚甲基桥联双环戊二烯基金属衍生物。

85 And 119486/79. They are a novel type of antibiotic having both the wide antibacterial spectrum and high safety of penicillin and cephem antibiotics belonging to beta -lactam antibiotics, as well as the potent antibacterial activity and high beta -lactamase stability of carbapenem antibiotics.Sodium-(5R, 6S)-6-[-1-hydroxyethyl]-7-oxo-3- [-2-tetrahydrofuryl]-4-thia-1-azabicyclo [3.2.0] hept-2-ene-2-carboxylate 5/2 hydrate (faropenem sodium, hereinafter referred to as compound 1) is currently used as an oral drug for various infectious diseases and is reported to show potent antibacterial activity against not only methicillin-sensitive Staphylococcus aureus, Streptococcus pyrogenes and Streptococcus pneumoniae but also gram-positive bacteria for which conventional beta -lactam drugs have proved ineffective such as penicillin-resistant pneumococci, oral staphylococci and enterococci, also showing a wide antibacterial spectrum covering gram-negative bacteria such as Haemophilus influenzae and anaerobic bacteria such as the genus Bacteroides, which activity is due to its novel skeleton penem ring (Kagaku Ryoho no Ryoiki The Field of Chemotherapy, Vol.

他们是一种新型的抗生素都具有广泛的抗菌谱和高度的安全青霉素和cephem抗生素，属于β-内酰胺类抗生素，以及作为强大的抗菌活性和高β-内酰胺酶稳定的碳青霉烯类antibiotics.sodium -（ 5 R ， 6 S ）-6 -[ - 1 -羟乙基] - 7 -氧- 3 - [ - 2 - t etrahydrofuryl] - 4 -硫杂- 1 -氮杂双环[ 3 。2.0]庚- 2 -节能- 2 -羧酸5 / 2水合物（法罗培南钠，以下简称为化合物1 ）是目前用来作为口服药物，为各种传染病和报道，以显示强大的抗菌活性，不仅对甲氧敏感的金黄色葡萄球菌，链球菌pyrogenes和肺炎链球菌，但也克阳性菌为常规β-内酰胺类药物已证明无效，如青霉素耐药pneumococci ，口腔葡萄球菌和肠球菌，也显示出广泛的抗菌谱，包括革兰阴性菌如流感嗜血杆菌和厌氧菌如属杆菌，这活动是由于其新颖的骨架青霉烯环（（化学ryoho没有ryoiki领域的化疗），第13卷，第10号，第74-80 ， 1997年）。

The results suggested that the reaction temperature, the ratio of oil to water, the amount of ethyl cellulose as dispersant, initial monomers composition, the drop manner and the amount of initiator, the stirring speed, the pH of the buffer and the elution process have great influence on the morphology such as diameter of the hydrogel beads.

研究结果表明，采用反相悬浮聚合法，以丙烯酰胺和N-乙烯基吡咯烷酮为共聚单体，N，N'-亚甲基双丙烯酰胺为交联剂，牛血清白蛋白为模板，可以制备BSA印迹共聚物微球；反应温度、水油比、乙基纤维素分散剂用量、初始共聚单体配比、引发剂用量和加入方式、搅拌速度、水相pH值以及后续洗脱条件等均对粒径等微球结构和形态产生明显影响。

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。