查询词典 anhydride

Maleic Anhydride is important organic raw material and the third biggest acid anhydride next to benzene anhydride and acid anhydride. In recent years, Maleic Anhydride is esterified and hydrogenised under pressure to make 1,4- butanediol butylene glycol, and it is also hydrogenised to tetrahydrofuran, which enables Maleic Anhydride to become the raw material for producing high-value-added products and to be more widely applied.

顺酐是重要的基本有机原料，也是世界上仅次于酸酐和苯酐的第三大酸酐，近年来，顺酐脂化低压加氢制1.4-丁二醇和顺酐加氢制四氢呋喃技术的开发成功，是顺酐成为生产高附加值产品的原料，应用领域有了更进一步的拓展。

In 1999, the national production capability of maleic anhydride is 166000 ton and the actual production is more than 100000 ton, With the rapid development of national economy, the down-stream products of maleic anhydride are being used in more and more fields and the market demand of maleic anhydride is increasing day by day.

随着国民经济的快速发展，顺酐下游加工产品的应用领域不断扩大，市场对顺酐原料的需求量也昌逐增长。

Cantharidin(exo,exo-2,3-Dimethyl-7-oxabicyclo[2,2,1]heptane-2,3-dicar- boxylic anhydride ) is an active principle of Lytta caragarae, Mylabris Phalerata and Epicauta gorhami, and exists in various other insect species.

中文摘要斑蝥素( Cantharidin； exo，exo-2，3-Dimethyl-7-oxabicyclo [2，2，1]heptane- 2，3-dicarboxylic anhydride )是一个来自昆虫的天然物。

Mylabris phalerata, Meloidae family of Coleoptera, has been known since antiquity to produce a potent toxic defensive agent, known as cantharidin (exo,exo-2,3-dimethyl-7-oxabicyclo [2.2.1] heptane-2,3- dicarboxylic anhydride), but well-known as Spanish Fly. In the past, Cantharidin has used as anticancer, herbicidal, pesticide and treatment of hepatic carcinoma and molluscum contagiosum activities.

中文摘要斑蝥为翘翅目芫青科斑芫青属的昆虫，主要成分为斑蝥素(Cantharidin； exo，exo-2，3-Dimethyl- 7-oxabicyclo [2，2，1] heptane-2，3-dicarboxylic anhydride)，研究中指出斑蝥素具有发泡、抗肿瘤的作用，或当作除草剂、杀虫剂、毛发生长刺激剂，目前临床上则用於治疗原发性肝癌及传染性疣。

The invention relates to polyimide molding powder with low melt viscosity and a preparation method, which uses 3,4'- diamino diphenyl ether, 3,3',4,4'-diphenyl ketone dicarboxylic anhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'- triphenyl diether dicarboxylic anhydride, 3,3',4,4'- diphenyl ether dicarboxylic anhydride and other monomers to polymerize at 100 to 140 DEG C, to get molding powder with a melt viscosity in the range of 1000Pa.s to 5000Pa.s.

本发明属于一种低熔体粘度聚酰亚胺模塑粉及制备方法，是采用3，4′-二氨基二苯醚同3，3′，4，4′-二苯酮四酸二酐、3，3′，4，4′-联苯四酸二酐、3，3′，4，4′-三苯二醚四酸二酐、3，3′，4，4′-二苯醚四酸二酐等单体在100～140℃聚合，获得熔体粘度在1000Pa.s～5000Pa.s范围内的模塑粉。

In this paper the study on optimizing the esterification of cellulose and some character of CAB(the degree of substitution of cellulose, solubility, the thermal properties and molecular weight) was discussed. The mechanism of the esterification of cellulose in butyric acid/ acetic acid/ butyric anhydride which comprises the creation of the acetic butyric anhydride, acetyl cation and butyryl cation was investigated by the study of the effect of the content of the organic acid and anhydride on the degree of acetyl and butyryl substitution of cellulose.

最后本文根据纤维素在丁酸/乙酸/丁酸酐中的酯化反应中有机酸以及酸酐的添加量对最后产物纤维素醋酸丁酸酯中乙酯或者丁酯取代度的影响，提出纤维素在丁酸/乙酸/丁酸酐中的酯化反应经历一个混和酸酐以及乙酰碳正离子、丁酰碳正离子的生成过程。

Mylabris phalerata, Meloidae family of Coleoptera, has been known since antiquity to produce a potent toxic defensive agent, known as cantharidin (exo,exo-2,3-dimethyl-7-oxabicyclo [2.2.1] heptane-2,3- dicarboxylic anhydride), but well-known as Spanish Fly. In the past, Cantharidin has used as anticancer, herbicidal, pesticide and treatment of hepatic carcinoma and molluscum contagiosum activities.

斑蝥为翘翅目芫青科斑芫青属的昆虫，主要成分为斑蝥素(Cantharidin； exo，exo-2，3-Dimethyl- 7-oxabicyclo [2，2，1] heptane-2，3-dicarboxylic anhydride)，研究中指出斑蝥素具有发泡、抗肿瘤的作用，或当作除草剂、杀虫剂、毛发生长刺激剂，目前临床上则用於治疗原发性肝癌及传染性疣。

Cis-butendioic anhydride, benzoic acid and phthalide in light fraction column T201 were removed on the column top, the overhead component: benezene anhydride 25.74%, cis-butendioic anhydride 39.11%, benzoic acid 25.37%, phthalide 9.78%.

轻组分塔T201中顺酐、苯甲酸、苯酞都在塔顶被除去，其中塔顶组成：苯酐25.74%，顺酐39.11%，苯甲酸25.37%，苯酞9.78%。

In the second part, quantum chemical AM1 methods were employedto theoretically investigate the electronic structures of maleic anhydride in ground- and excited-states. On basis of the frontier orbital theoryand three bonding principles, the possibility of reaction of active α-hydroxysuccinic anhydride carbanion and active α-hydroxy-succinic anhydride radical on polymerization process of MArespectively by alkali catalyst and by hydroxyl radical was discussed. Theanionic and radical polymerization of MA discussed also. Theoreticalstudies show that both polymerization products of MA are in the chainstructures, corresponding to the experimental findings.

第二部分用量子化学AM1方法，计算研究了马来酸酐的基态和激发态电子结构；应用前线轨道理论和成键三原则分别探讨了碱催化条件下和羟基自由基引发下马来酸酐均聚合过程中α-羟基丁二酸酐碳阴离子和α-羟基丁二酸酐碳自由基活性中间体参与反应的可能性及由它们引发的马来酸酐阴离子聚合反应机理和自由基引发聚合反应机理；理论研究表明马来酸酐的均聚合产物均为链式结构，与实验事实相相符。

A series of imides oligomers were synthesized with the phenylethynylphthalic anhydride , nadic anhydride and cyanophthalic anhydride as endcapped agents.

我们以苯乙炔苯酐、降冰片烯二酸酐和氰基苯酐为封端剂合成了一系列的酰亚胺低聚物。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。