链二烯

The cytotoxicity of these compounds were valuated by MTT and SRB methods using three cancer cell lines: HL-60, A-549, P-388. Cyclo-shikonin, and cyclo-alkannin have high cytotoxicity against HL-60.The chiral center of side chain has no effect on their activity. 2- 1-(Acetyloxy-4-methyl-3-pentenyl -5, 8-dihydroxy-1, 4-naphthoquinone (105) has strong inhibition effect on P-388 cells. 2- 1-(isooctyloxy-4-methyl-3-pentenyl -5, 8-dihydroxy-1, 4-naphthoquinone (108) and 2- 1-(2-furoyloxy-4-methyl-3-pentenyl -5, 8-dihydroxy-1, 4-naphthoquinone (112) have high inhibition on A-549.Shikonin (1), alkannin (2), and their derivatives have the structural features of a planar chromophores and short side chain. We examined the ability to inhibit the telomerase.

抗肿瘤活性初步筛选测试采用小鼠白血病P-388肿瘤细胞和人肺癌A-549肿瘤细胞进行，结果表明侧链羟基的手性对抗肿瘤活性无明显影响；有数个化合物具有很好的体外抑制活性，特别是化合物2-（1-异辛酰氧基-4-甲基-3-戊烯基）-5，8-二羟基-1，4-萘醌（108）和2-[1-（2-呋喃甲酰氧基）-4-甲基-3-戊烯基]-5，8-二羟基-1，4-萘醌（112）体外显示对人肺癌A-549肿瘤细胞有强效；2-（1-乙酰氧基-4-甲基-3-戊烯基）-5，8-二羟基-1，4-萘醌（105）对小鼠白血病P-388肿瘤细胞有强效；环紫草素和环异紫草素对人白血病HL-60细胞有强烈抑制作用。

Because of its structure, the length of the different isoprenoid side chain can form different coenzyme Q.

因其结构中，类异戊二烯侧链的长度不同，可形成不同的辅酶Q。

The properties of single-chain and pauci-chain polystyrene microspheres and recent results on the electron microscopy and selected area electron diffraction of single-chain monocrystals of polyethylene oxide, isotactic polystyrene, cis-1, 4-polybutadiene and guttapercha are presented and discussed.

介绍和讨论了单链和寡链聚苯乙烯玻璃体微球的性质以及聚环氧乙烷、全同立构聚苯乙烯、顺-1， 4-聚丁二稀、反-1， 4-聚异戊二烯单链单晶电子显微镜和选区电子衍射观察的最新结果。

In addition nC〓, nC〓, two isomers of C〓 sterene and three isomers of C〓 isoprenoid hydrocarbons were also identified from aliphatic fraction of pyrolyzed product at 200℃. After pyrolyzed at 300℃, the main aliphatic hydrocarbons were normal alkanes ranged from C〓 to C〓, with C〓 as the main peak and C〓 as the second main peak. Meanwhile, pristane, phytane and C〓 sterane were also detected. In the pyrolysates at 400℃ and 500℃, the content of saturated hydrocarbons decreased, the range of normal alkanes distribution became narrow and the main peak was nC〓. Low concentration of C〓-C〓 steranes was detected and the content of C〓-C〓 increased more.

在200℃热模拟产物饱和烃馏分中除检测出两种长链烯烃外，还检测到正十九碳单烯烃、正三十五碳双烯烃、两个碳二十八甾烯的同分异构体和三个C〓类异戊二烯烷烃化合物同分异构体。300℃模拟产物饱和烃主要为正烷烃，正烷烃的碳数分布范围为C〓-C〓，以C〓为主峰、C〓为次主峰；另外，样品中还检出姥鲛烷、植烷和C〓甾烷等化合物。400和500℃热模拟产物中的饱和烃含量下降，正烷烃系列碳数分布范围变窄，主峰碳后移至C〓，检测到低浓度的C〓-C〓甾烷系列化合物，另外，C〓-C〓藿烷系列化合物含量进一步增加。

Retene, simonellite, pimarene and long side chain indanes were identified in algal pyrolysates for the first time.

首次在藻类热模拟产物中检测到惹烯、西蒙内利烯、海松烯及长侧链二氢化茚类化合物。

The properties of single chain and pauci chain polystyrene microspheres and recent results on the electron microscopy and selected area electron diffraction of single chain monocrystals of polyethylene oxide, isotactic polystyrene, cis1,4 polybutadiene and gutta percha are presented and discussed.

介绍和讨论了单链和寡链聚苯乙烯玻璃体微球的性质以及聚环氧乙烷、同立构聚苯乙烯、－，4－丁二稀、－，4－异戊二烯单链单晶电子显微镜和选区电子衍射观察的最新结果。

From the experiment discovered for the first time the dimethyl ether may substitute CO to take the chain-carrying agent of the peroxy free radical chemistry amplifier system, and optimized the CH_3OCH_3-NO-HO_2 chemistry amplifying system determination condition, the CH_3OCH_3 best density is 1.876 ppmv, the NO best density is 1.3ppmv, and obtained this method chain length CL=124, 5 parallel determinations densities of HO_2 are the 44.0pptv, the relatively standard deviation is smaller than 4%; Although chemistry box model computed result indicated the dimethyl ether, the ethene, the propene and the ethanol all can take the chain-carrying agent of the peroxy free radical chemistry amplifier system, and their simulation chain length all grows up compared to the CO-NO-HO_2 chemistry amplifying systems, but experiments proved the ethene, the propene and the ethanol have not suit the chain-carrying agents.

首次从实验上发现二甲醚可以替代CO作为过氧自由基化学放大系统的链传递试剂，并优化了CH_3OCH_3-NO-HO_2化学放大系统的测定条件，CH_3OCH_3的最佳浓度是1876ppmv，NO的最佳浓度为1.3ppmv，并得到了这一方法的链反应长度(CL=124)，5次平行测定浓度为44.0pptv的HO_2自由基，相对标准偏差＜4％；虽然化学盒子模式计算结果表明二甲醚、乙烯、丙烯和乙醇都能作为过氧自由基化学放大系统的链传递试剂，并且它们的模拟链长都比CO-NO-HO_2化学放大体系的链长大，但是实验证明乙烯、丙烯和乙醇不适合作为过氧自由基化学放大系统的链传递试剂。

The reason for inelastic deformation of unvulcanized rubber can be found in its chemical structure: rubber is composed of long polymer chains.

二烯烃类化合物在经过聚合后，主要生成的是线形的高分子长链。

The result of potassium malonyloxyborohydride as a new hydroboration reagent reacts with terminal alkenes and alkynes is described.

介绍新的硼氢化试剂丙二酰氧基硼氢化钾与链端烯炔烃的作用，烯烃的硼氢化物在PTC条件下，插入∶CCl2 ，可得饱和羧酸；炔烃则难以与之硼氢化。

Alkylation of C6D6 with 1-dodecene using Br-ALCl3 as a catalyst was firstly carried out. Molecular structures of products, dodecylbenzene isomers, were analyzed by GC-MS and NMR, and the deuterated atom in the dodecylbenzenes was verified to be connected with 1-carbon of the side chain.

首先进行了Br-AlCl3催化氘代苯与1-十二烯烃的反应，通过GC-MS及NMR分析产物十二烷基苯同分异构体的结构，验证了氘原子与产物侧链1-位碳相连的结论。

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。