查询词典 allyl

Our synthesis is characteristic of ready availability of starting material (piperonal, ethyl oxalate, allyl bromide, ethyl 4-bromobutyrate), operationally simple reactions with cheap reagent chemicals, and atom economy.

在合成过程中，我们没有使用任何保护基，也没有将反应活性中心氮原子钝化；相反地，利用这一富电子活性中心的许多反应来构筑我们的三尖杉碱环系。

As a precursive work of polymerization directly from vesicles, a polymerizable surfactant, allyl dodecyl dimethylammonium bromide was synthesized, and spontaneous stable vesicles were formed from aqueous solutions of ADDB and sodium dodecyl sulfonate in equimolar composition.

作为可聚合囊泡制备的前期基础工作，研究了一种可聚合的囊泡体系：1-丙烯基－2，2，二甲基－十二烷基溴化胺和ADDB与十二烷基磺酸钠的等摩尔比混合体系。

Analysis of the material change, garlic cells bioactive aliphatic thio cysteine sulfoxide and thiosulfate propenyl cysteine sulfoxide sulfur compounds in garlic, such as the role of enzymes, the generation of thiobarbituric acid sub - ester, propylene-based thiosulfinates, allyl thiosulfinates as garlic pigment precursor substances, and further changes occurred in the green garlic.

从物质变化分析，大蒜细胞中的生物活性物质硫代脂肪族半胱氨酸亚砜和硫代丙烯基半胱氨酸亚砜等含硫化合物在蒜酶的作用下，生成硫代亚磺酸酯、丙烯基硫代亚磺酸酯、烯丙基硫代亚磺酸酯，作为大蒜色素物质的前体，进一步发生大蒜绿变。

In this thesis, three different chain length hybrid monomers, containing acrylate and propenyl ether group, was synthesized by three-step reaction through 1.3-propanediol, 1.4-butanediol, 1.6-hexanediol, allyl bromide and acryloyl chloride.

本文以1.3-丙二醇、1.4-丁二醇、1.6-己二醇、烯丙基溴及丙烯酰氯为主要原料，通过三步反应合成了三种不同链长的丙烯酸酯-丙烯基醚杂化单体。

We prepared the pyrethric acid II through four reactions: esterification, oxidation, decomposition, diesterification. And the original synthesis route of the pyrethric acidII was improved: the yield of oxidation of allyl rise through increasing the activity of Selenium dioxide; in the document, tert-butyl-trans -2, 2-dimethy1-3-(2"-methoxycarbony1-1"-propenyl)cyclopropanecarboxy late was synthesized from tert-butyl-trans-2,2-dimethyl-3-(2 -formyl-r -propenyl) cyclopropanecarboxylate with two steps, with low yield.

我们经过酯化，氧化，成双酯，热分解四步反应，成功地得到了第二菊酸，并改进了原第二菊酸的合成路线：通过改变二氧化硒的活性提高了烯丙甲基的氧化产率；将原路线中醛氧化成羧酸、羧酸酯化的两步反应改为醛和甲醇、二氧化锰等作用一步直接酯化的方法，减少了反应步骤，提高了总收率。

The company has the most advanced color plate production line, can produce allyl polystyrene, rock wool, polyurethane, glass wool as core material of high I-type, H-type color steel and sandwich the roof of corrugated board.

公司拥有最先进的彩钢板生产线，可生产聚苯烯，岩棉，聚氨酯，玻璃棉等为芯材的企口式，H式彩钢板及瓦楞夹心屋顶板。

Liquid-phase epoxidation of allyl chloride with hydrogen peroxide was carried out over Ti-MWW, a novel titanosilicate with the MWW structure, to synthesize epichiorohydrin selectively and effectively. Ti-MWW proved to be superior to the conventional TS-1 catalyst in both catalytic activity and product selectivity. Ti-MWW prefers aprotic solvents of acetone and acetonitrile, both of which can restrain the solvolysis of epichiorohydrin, whereas TS-1 favors a protic solvent of methanol.

研究了具有MWW结构的新一代钛硅分子筛Ti-MWW催化剂对烯丙基氯液相环氧化高效合成环氧氯丙烷的催化性能结果表明，Ti-MWW的催化活性以及产物选择性均优于传统的钛硅分子筛TS-1，对于Ti-MWW，合适的溶剂为非质子性溶剂丙酮和乙腈，在该溶剂中环氧化物不易发生溶剂化开环反应；而对于TS-1，合适的溶剂是质子性溶剂甲醇，但甲醇可导致醇醚副产物的生成。

Selenium, sulfur and other organic compounds in vegetables: onions, garlic is rich in sulfur, selenium and "sulfonyl allyl cysteine," can help the liver detoxify and prevent liver cancer.

五、含硒、硫等有机化合物的蔬菜：葱、蒜含丰富的硫、硒及「磺烯丙基半胱氨酸」，能帮助肝脏解毒及防止肝癌发生。

Second, using DBU as the base for enolization of propargylic esters of unsaturated acids 18e-k, we developed a tandem Ireland-Claisen rearrangement /isomerization reactions. It has been shown that the reaction sequence affords triene molecules 42a-b and 43a-b in moderated to high yields. Interestingly, with allyl hexa-3,5-dienoates 18i-j as the substrate, the rearranged products underwent further aromatization to give uniquely substituted benzyl acids 44a-b.

其次，以含有活泼质子的烯酸炔丙酯18e-k为底物，在DBU为烯醇化碱、TMSCl为硅试剂的条件下，底物18e-h发生了Ireland-Claisen重排/异构化串联反应，得到完全共轭的三烯类化合物42a-b及43a-b；而以己二烯酸炔丙基酯18i-j为底物时，重排/异构化后的产物进一步发生电环化等反应最终得到芳构化产物——取代苯甲酸类化合物44a-b。

Its beneficial widespread effect on health is attributed to sulphur compounds and particularly to thiosulfinates. Odorless and stable, alliin is the most abundant sulfur compound in whole, unbruised Garlic. When the clove of garlic is cut or crushed, the enzyme alliinase is released from its compartment and transforms S-allyl-L-cysteine sulfoxide or alliin into diallyl thiosulfinate allicin, the characteristic compound of garlic flavor. This very unstable thiosulfinate is rapidly degraded to related organosulfur compounds. Allicin is often thought of as the "active ingredient" in Garlic, and has been the subject of numerous scientific studies, but its a fairly unstable compound that likes to react with itself.

蒜氨酸(S-烯丙基-L-半胱氨酸亚砜，alliin)是完整、未受损大蒜里面含量最丰富的硫化物，并且非常稳定，它存在于大蒜的细胞质里；当细胞受损时，蒜氨酸酶从细胞液向细胞质释放，蒜氨酸和蒜氨酸酶接触被迅速转化为一系列新的化合物—蒜辣素及其相似物，蒜辣素(双烯丙基硫代亚磺酸酯，allicin)被认为是大蒜中最重要的活性成分，但它相当不稳定，易于自身反应。

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。