环二酯

Steam distillation essential oil principal constituent is bornyl acetate, borneol,2,3-dimethyl-bicyclo , hept-2-ene,caryophyllene,camphene,d-d-cadinene,?

水蒸气蒸馏所得的冷杉精油主要成分为：乙酸龙脑酯，龙脑，2，3-二甲基-双环[2.2.1]-庚-2-烯，石竹烯，莰烯，杜松烯，？

Compareing with essential oil of the steam distillation method and the bensine solvent extraction method through GC-MS analysis .The result showed that:the essential oil principal constituent extracted by benzine is camphene,a-pinene,bornyl acetate, limonene, 1-methyl-4-(1-methylethyl)-1,4-cyclohexadiene, myrcene, caryophyllene, borneol.

对巴山冷杉针叶水蒸气蒸馏和石油醚萃取所得精油的GC-MS 分析对比研究结果表明：石油醚萃取精油主要成分为：莰烯，a-蒎烯，乙酸龙脑酯，柠檬烯，1-甲基-4-异丙基-1，4-环己二烯，月桂烯，石竹烯，龙脑。

In the process of producing soft urethane polyester foamed plasics,CFCs as forming agent are replaced by cyclopentane whose value of ozone depletion is zero to decrease the destruction of environment,and the modified poly-ether-alcohol is used as reactants through one-step reaction.

为了解决软质聚氨酯泡沫塑料生产过程中的环保问题，采用臭氧消耗值为零的环戊烷为物理发泡剂替代严重破坏臭氧层的氯氟烃，以改性聚醚多元醇与甲苯二异氰酸酯等为主要反应物，一步法反应研制试产了软质聚氨酯泡沫塑料。

The effects of larium salt, cerium salt and praseodymium salt on thermal stability of PVC were studied, the synergistic effects of rare earth stabilizers with PDOP,β- diketone and ESO were also investigated by heat aging test, witheness test, conductivity test and TG analysis.

通过热老化测试、白度测试、电导率测试和热重分析，研究了镧、铈、镨盐对PVC热稳定性能的影响，同时考察了辅助热稳定剂亚磷酸酯、β-二酮和环氧大豆油与稀土类稳定剂的协同效应。

In our research on study chemical reaction of active methylene compounds and brom-acetophenone. Because of brom-acetophenone is compound that contain carbonyl and halogen ,which will take place electrophilic substitution and nucleophilic addition. When active methylene compounds are ethyl acetoacetate and β-diketone, controlling reaction condition, we have found that mono-substitution's production and di-substitution's. production is isolated; active methylene compounds are acetoacetanilide and acetoacetanilide derivate, pyrrolidin-2-one derivants were obtained by substitution and close-ring reaction .but there is no report about it.

本文是让活泼亚甲基类化合物与溴代苯乙酮发生化学反应，由于溴代苯乙酮是含有羰基的卤代烃结构，它可以发生亲电取代和亲核加成反应，当活泼亚甲基类化合物为乙酰乙酸乙酯和β-二酮时，控制反应条件可以发生单取代和双取代两种产物；当活泼亚甲基类化合物为乙酰乙酰芳胺类化合物来反应时，溴代苯乙酮中的羰基与氨基会发生分子内的关环反应生成吡咯烷-2-酮衍生物，这在以前的研究中是没有发现的。

Complex 9 was characterized by IR and elemental analysis. Structure determination revealed it is a dimer.

配合物9是二聚体，它对己内酯的开环聚合没有催化活性。

The main photoproducts in dioxane and hexane are 2-chloro benzamide and 4-chlorophenyl isocyanate.

在二氧六环及正己烷中的主要光解产物为邻氯苯甲酰胺和对氯苯基异氰酸酯。

Polyfluoroalkyl iodides could react with unsaturated olefin acids in the presence of sodium dithionite by radical addition to give adducts. It was found that these adducts could form polyfluoroalkyl substituted γ or δ-lactones due to intramolecular nucleophilic substitution in the alkali solution.

研究发现：多氟烷基碘化物在连二亚硫酸钠存在下与不饱和烯酸经自由基加成得到的产物，能在碱性条件下进行分子内亲核取代反应形成五元或六元环的含氟内酯类化合物。

Bromo-5-formyl -3-methylpyrrole is an important intermediate of tolyporohin. On the base of introducing the present research and development of tolypo- rohin and pyrroles ramification at home and abroad, an emphasis was made on synthesis of 2-Bromo-5-formyl -3-methylpyrrole and the technical conditions of all steps, which was described as follows. Diethyl 3,5-dimethylpyrrole-2,4-dicarboxylate was made by nitrification, reduction and cycle of ethyl acetoacetate.

由于2-溴-5-甲酰基-3-甲基吡咯是合成托尼卟吩的重要中间体，本文在阐述了当前托尼卟吩及吡咯衍生物的国内外研究和开发的基础上，重点研究了2-溴-5-甲酰基-3-甲基吡咯的合成，并对各步反应进行了工艺研究，具体合成步骤如下：本文通过对乙酰乙酸乙酯的亚硝化、还原、成环，反应生成吡咯单环衍生物2，4-二乙氧羰基-3，5-二甲基吡咯。

Bromo-5-formyl -3-methylpyrrole is an important intermediate of tolyporohin. On the base of introducing the present research and development of tolypo- rohin and pyrroles ramification at home and abroad, an emphasis was made on synthesis of 2-Bromo-5-formyl -3-methylpyrrole and the technical conditions of all steps, which was described as follows.

由于2-溴-5-甲基-3-甲基咯是合成托尼吩的重要中间体，本文在阐述了当前托尼吩及咯衍生物的国内外研究和开发的基础上，重点研究了2-溴-5-甲基-3-甲基咯的合成，并对各步反应进行了工艺研究，具体合成步骤如下：本文通过对乙乙酸乙酯的亚硝化、还原、成环，反应生成咯单环衍生物2，4-二乙氧羰基-3，5-二甲基咯。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。