乙酸

Naphthalene acetyl chloride was prepared firstly by the reaction betweenα-naphthylacetic acid and SOCl2 in anhydrous benzene, then reacted with potassium thiocyanate to obtainα-naphthalene acetyl isosulfocyanate, as taking an addition reaction with p-chloro benzoyl hydrazine the novel compound N-naphthalene acetyl-N'-p-chloro benzoylamino thiocarbamide was finally synthesized.

通过α-萘乙酸和SOCl2在无水苯中反应制得α-萘乙酰氯，然后与硫氰酸钾反应生成α-萘乙酸基异硫氰酸酯，再与对氯苯甲酰肼进行加成反应，生成新型化合物N-萘乙酰基－N'-对氯苯甲酰氨基硫脲。

Cellulose diacetate and cellulose triacetate, for example, are not attacked by microorganisms because most of the hydroxyl groups have been converted to acetate groups.

比方说由于大部分的羟基已经被转化成了醋酸基，双乙酸纤维素和三乙酸纤维素就不再受微生物的侵蚀。

The influences of reaction temperature and sulfuric acid concentraction on trichloroethylene conversion and chloroacetic acid recovery have been investigated.

研究了三氯乙烯水解法生产氯乙酸的工艺，并在两种不同的实验方案中考察了反应温度、硫酸浓度对三氯乙烯转化率和氯乙酸收率的影响并确定了适宜的工艺参数，可作为工业化生产研究的基础。

The reparing high molecular material was divided into absorbable and unabsorbable material,the former included polyglycolic-acid and polyglaction,the later consists of polypropylene polyester and expanded polytetrafluoroethylene.

人工高分子修补材料主要有可吸收和不可吸收两大类，前者有聚羟基乙酸和聚乳酸羟基乙酸两种，后者有聚丙烯网、膨体聚四氟乙烯片及聚酯纤维网。

The results of in vitro culture show that sodium fumarate increased NDF digestibility, total volatile fatty acid concentration and propionate proportion, decreased ammonia concentration, and acetate, butyrate, and valerate proportions, and acetate to propionate ratio when using bermudagrass hay as the substrate.

体外培养的结果显示，当使用百慕达乾草为受质时，添加延胡索酸钠，提高了中洗纤维消失率、总挥发性脂肪酸浓度和丙酸的百分比，降低了氨浓度、乙酸、丁酸和戊酸的百分比，乙酸对丙酸的比例降低。

The results show that there were no significant differences among the four forage rations in rumen pH, the concentrations of total volatile fatty acids, acetate, propionate, the ratios of acetate to propionate, butyrate, isobutyrate and valerate（P﹥0.05）. Only in 11:30, the concentrations of isovalerate caused by ration A and B were significantly higher than the other two rations(P﹤0.05).The milk yield caused by the ration C was significantly lower than the others (P﹤0.05). However, there were also no significantly differences among these four rations in the DM, fat, sugar, protein and scc of the milk. The milk fat and sugar of ration B and C were higher than ration A and D in number as well.

试验结果显示：各粗料组合日粮对各个时间点的瘤胃发酵指标：pH、TVFA、乙酸、丙酸、乙酸/丙酸、丁酸、异丁酸、戊酸浓度均无显著差异（P﹥0.05），只在11：30时，日粮A、B的异戊酸浓度显著低于日粮C、D (P﹤0.05)；日粮C的产奶量显著低于其它三个日粮，而在乳干物质、乳脂、乳糖、乳蛋白、体细胞数上，各日粮均无显著差异，从数值上看，日粮B、C的乳脂和乳糖高于A、D。

A vinegary smell is caused by acetic acid, while a nail polish aroma reflects the formation of ethyl acetate.

葡萄酒中也会闻到破败气味。像醋气味是由乙酸造成的，而指甲油味是由乙酸乙酯形成的。

Effects of catalyst dosage, kind of water carrier, ratio of raw material and reaction time were investigated.

以乙酸、甘油为原料，通过酯化反应合成乙酸甘油酯。

AbstractAIM: To study the occurrence of ocular surface diseases on staffs working in operating room and to investigate the relation between xerophthalmia occurrence and peroxyacetic acid contiguity.

目的：观察与过氧乙酸有密切接触人群的眼表情况，来分析过氧乙酸接触对干眼症发病率的影响。

A series of p-toluene sulfonylamido acetacylhydrazone derivatives were synthesized from p-toluenesulfonyl chloride which reacted with glycine to get the intermediate p-toluene sulfonylamido glycine, then through the esterification, hydrazinolysis to afford another intermediate p-toluene sulfonylamido acethydrazide, which condensed with different aldehydes to obtain the target compounds that were characterized by IR, 1H NMR, 13C NMR spectra and elemental analysis.

魏太保 ；冷艳丽；王永成；张建辉；张有明*摘要：以对甲苯磺酰氯为原料，通过与氨基乙酸反应得到中间体对甲苯磺酰氨基乙酸，再经酯化、肼解得到对甲苯磺酰氨基乙酰肼，然后与相应的醛缩合得一系列对甲苯磺酰胺基乙酰腙类化合物。其结构经元素分析， IR， 1H NMR和13C NMR确证。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐