异戊酸

Based on the analysis of the chromatogram of flavoring compositions of Taishan Tequ, 13 kinds of flavoring compositions including n-propanol, isoamyl alcohol, ethyl caproate, ethyl lactate, ethyl acetate, ethyl butyrate, caproic acid, acetic acid, butyric acid, acetaldehyde, acetal, total acids and total esters were determined as the chromatogram skeleton compositions of Taishan Tequ. The physiochemical indexes of Taishan Tequ could be under proper control through the stipulation of the content range of the above flavoring compositions, which is an effective way to liquor quality improvement and stability and has greatly improved the blending techniques of Taishan Tequ.

以泰山特曲酒香气成分色谱分析结果为基础，确定了正丙醇、异戊醇、己酸乙酯、乳酸乙酯、乙酸乙酯、丁酸乙酯、己酸、乙酸、丁酸、乙醛、乙缩醛、总酸、总酯这13种香味成分作为泰山特曲的色谱骨架成分来控制成品酒理化指标，并制订了控制范围，使泰山特曲的勾兑技术有了飞跃的发展，成为提高与稳定产品质量的有效方法。

Methods: The effects of the ratio of reactants, the amount of the catalyst used, the reaction time and the amount of an water-taking agent on synthesizing isoamyl cinnamate were investigated to obtain a suitable condition for synthesizing the ester.

考察了醇酸比、反应时间、带水剂用量等因素对合成肉桂酸异戊酯的影响，得到合成该酯的较适宜条件。结果：最佳反应条件为n：n=5：1，催化剂用量为肉桂酸用量的20%，反应时间2h，反应温度110～118℃，酯收率可达76.6%。

The result was shown as follows:compared with the good quality beer,the diacetyl,aldehyde,islobutyl alcohol,isoamyl alcohol and total acid were higher,however,propyl alcohol and ethyl butyrate were lower

研究中还发现污染细菌后的发酵过程中的pH下降迅速，降糖加快，最终得到的啤酒中双乙酰、乙醛、异戊醇、异丁醇和总酸偏高，而正丙醇、丁酸乙酯含量偏低。

The mass transter can be enhanced ,when we introduce sulfuric acid and cuprous oxide into this system.The model is formed to describe the transference of the martial between the four phases: gas-liquid-liquid-gas, which can explain some problems. We analyze the dead of the catalyst, and make a conclusion that the surface of the catalyst is covered with some compounds such as bluestone, which lessen the activity points of the catalyst and debase the activity.

在SO_4~(2-)／ZrO_2-La_2O_3催化的反应系统中加入稀硫酸和氧化亚铜促进了异丁烯和一氧化碳的传质、使反应得以快速，高选择性的进行，异丁烯的转化率达95％以上，特戊酸的收率达47％；讨论了g-l-l-s传质过程；对催化剂作了失活分析，催化剂失活的原因是因为反应后的催化剂表面覆盖了一层硫酸盐，使催化剂的活性中心数减少，活性降低。

In comparison with the organic solvents as reaction medium, higher conversion was achieved the tert-ethyl valerate could be formed in the ionic liquid medium.

当反应体系中存在水时，有特戊酸生成。表明反应中2，2，4-三甲基戊烷首先发生β-断裂反应，生成叔丁基正碳离子和异丁烯。

The Rhizopus delemar lipase catalyzed synthesis of isoamyl valerate in organic solvents was studied, and the optimum condition for the esterification was acquired.

德氏根霉菌经固态发酵生产脂肪酶，以此酶为催化剂，在非水介质中合成了正戊酸异戊酯。

Both star copolymer precursors are hydrolyzed in the acidic conditions, then the corresponding recovered star copolymers of EO and glycidol with multi pending hydroxylmethyls are esterified with 2-bromoisobutyryl bromide to produce the ATRP macroinitiators with multi pending bromoisobutyryl groups . Then the latters initiate the polymerization of styrene to form the corresponding amphiphilic three- and four-arm star PEO-g-PS.

在阴离子共聚EPEE单体和环氧乙烷单体的过程中，通过变换引发剂体系中的醇的结构(由原来的二元醇变成多元醇，如三羟甲基丙烷和季戊四醇)，合成了星形结构的共聚物，通过水解反应脱去保护基团后，再与2-溴异丁酰溴反应，得到链的侧端挂有很多2-溴异丁酸酯基的星形大分子引发剂，通过ATRP聚合机理引发苯乙烯聚合得到PEO为主链，PS为侧链的星形一接枝共聚物。

Several routes for synthesizing methyl isopropyl ketone were introduced, including the main methods based on isobutyl aldehyde-acetic acid, isobutyric acid -acetic acid, methyl ethyl ketone-formaldehyde and isoprene.

介绍了甲基异丙酮的多种合成路线，主要有异丁醛-乙酸法、异丁酸-乙酸法、甲基乙基酮-甲醛法和异戊二烯法。

The resin which was synthesized by the materials of hydroxy silicone oil , 1, 6-hexamethylene diisocyanate, tolylene diisocyanate, pentaerythritol triarylate and 2-hydroxy ethyl acrylate is able to cure rapidly at room temperature by UV.

本实验采用溶液聚合的方法，以端羟基硅油、甲苯二异氰酸酯、六亚甲基二异氰酸酯、丙烯酸—2—羟基乙酯和季戊四醇三丙烯酸酯为原料制备出了新型能够进行快速固化、高效的三官能度封端的光固化反应体系。

This article has carried on an overview of biosynthetic pathway of terpenoids and the HMG-CoA reductases.

人参皂苷等萜类生物合成分为甲羟戊酸和丙酮酸两种途径，两者都是以异戊烯基焦磷酸为主要的中间产物。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。