二聚

The aim of this study was to develop a novel amphiphilic functional block poly(ε-caprolactone) bearing ketone groups MPEG-b-P(OPD-co-CL. 2-oxepane-1, 5-dione was copolymerized with ε-caprolatone in which methoxy poly (MPEG, Mn=5 000) and stannous octoate were used as initiator and catalyst, respectively. The syntheses were conducted by bulk and solution polymerization. 1H NMR results showed that peak position and splitting of the polymers synthesized through solution polymerization were consistent with theoretical data, demonstrating the products were designed block copolymers. While in the bulk polymerization, polymer peak position was changed due to their high reaction temperature, suggesting their structural variation.

将带有羰基官能团的4-羰基己内酯和ε-己内酯分别在甲氧基聚乙二醇(MPEG，Mn=5 000)为引发剂，异辛酸亚锡为催化剂溶液和本体体系中开环聚合，合成了两亲性侧基带有羰基官能团的聚己内酯嵌段共聚物MPEG-b-P(OPD-co-CL.1H NMR结果表明采用溶液聚合法合成的聚合物各峰的峰位置和分裂情况与理论一致，证明了产物是实验所设计的嵌段共聚物，而采用本体聚合法合成的聚合物由于温度的影响，聚合物各峰的峰位置发生了变化，说明其结构发生了变化；差示扫描量热法分析结果表明随着OPD单体含量的增加，聚合物的熔点，玻璃化转变温度和熔融焓增加；热失重测试结果表明OPD单体的引入增加了聚合物的热敏感性。

Linear and star-shaped hydroxy-terminated polys were synthesized by reacting L-lactide with co-initiators such as poly,hydroxyethyl methycrylate,trimethylolpropane,mannitol and sorbierite in the presence of stannous octoate as catalyst.

以辛酸亚锡为催化剂，分别以聚乙二醇、甲基丙烯酸羟乙酯、三羟甲基丙烷、季戊四醇、甘露醇和山梨醇等和L-丙交酯反应，得到末端为羟基的线形和星形聚L-丙交酯。

As one of aliphatic polyether-ester, poly (p-dioxanone) shows not only excellent biodegradability, biocompatibility and bio-absorbability, but also good flexility, tensile strength and knot strength. The PPDO has already been used in some biomedical materials such as suture, bone repair device and may have potential application in peroral or parenteral drug delivery systems.

聚对二氧环己酮是脂肪族聚醚酯的一种，不仅具有优良的生物降解性、生物相容性和生物可吸收性，而且具有出色的柔韧性、抗拉强度和结节强度，可应用于生物医用材料，例如手术缝合线、骨科修复材料等，并在口腔和非肠道给药系统中具有潜在的应用前景。

In the presence of Pt catalyst, polyhydrodimethylsiloxane reacted with allyl polyoxyethylenepolyoxypropylene ether (F-6) by hydrosilylation to form an intermediate polyether silicone, which further undergo phosphation reaction with phosphorous pentoxide, a kind of phosphate modified polyethersiloxane surfactant was prepared.

采用铂作催化剂，通过含氢硅油和端烯基聚醚（F-6）的硅氢化加成反应先制得聚醚硅油中间体，再将其和五氧化二磷进行酯化反应，制得了一种磷酸酯型有机硅表面活性剂。

The spectral test results indicate that besides polyphosphoric acid,silicon phosphates on silica supported H_3PO_4 are also formed.On silica supported NaH_2PO_4 only sodium polyphosphates are present.

光谱试验结果显示，在二氧化硅负载的磷酸上，除了聚磷酸外，还有硅磷酸盐的存在；在二氧化硅负载的磷酸二氢钠上，仅发现聚磷酸钠存在。

A flame retarding and smoke suppressing agent polyphosphoric cyanamine urea was prepared with phosphoric acid,melamine and urea as the raw materials.

以磷酸、三聚氰胺、尿素为原料制备阻燃抑烟剂聚磷酰氰胺脲，然后将其应用于TDE-85#环氧树脂中，以顺丁烯二酸酐为固化剂制备了阻燃抑烟环氧树脂。

Polyvinylidene Fluoride PVDF homopolymer conforming to ASTM D-3222, Type I, Grade 2, is a tough, abrasion-resistant fluorocarbon material that has a design stress of 1,360 psi at 73°F and a maximum service temperature of 280°F.

聚偏二氟乙烯PVDF均聚物，符合ASTM D-3222，类别1，等级2标准，是一种坚固的、耐磨的碳氟化合物材料，在22oC下，其设计应力为1，360 psi，最高工作温度达到137oC。

Tri-cyanurate as a excellent additional retardant was synthesized by using cyanuric chloride_3,tribromophenol as main materials and under the condition of sodium hydroxide,dichloromethane,toluene as solvent respectively.

以三聚氯氰3和三溴苯酚为主要原料，在碱性条件下，分别以二氯甲烷、甲苯作为溶剂，合成了一种性能优良的添加型阻燃剂三三聚氰酸酯。

BR is embedded in the purple membrane and organized in trimeric unit arranged in a hexagonal twodimensional crystalline lattice, there are about 30 lipid molecules surrounding a BR trimer.

BR分子在紫膜中以三聚体的形式存在，并形成二维的六角型晶格，每个三聚体周围约有30个脂质分子。

Next, another novel diamine, 5-5-(4-phenyl-1,3,4-oxadiazol-2-ylbenzene-1,3-diamine, was prepared and polymerization was carried out in the same way to obtain polyimides containig triphenylamine units and 1,3,4-oxadiazole moieties in the side chain .

接下来，合成另一个新型双胺5-5-(4-phenyl-1，3，4-oxadiazol-2-ylbenzene-1，3-diamine后，以相同方法进聚缩合反应，可制得另一系列三苯胺和1，3，4-恶二唑为侧链的聚醯亚胺。

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。