查询词典 chemical synthesis

D-lactic acid is considered to be a very important chemical compound as a chiral material or intermediate in organic synthesis. D-LA is a prosoma of many chiral compounds with applications not only in the pharmaceutical and cosmetic industry but also in highly efficient and lowly toxic pesticide and herbicide.

D-乳酸是重要的手性中间体与有机合成原料，是多种手性物质的前体，广泛应用于制药、化妆品和高效低毒农药及除草剂等领域的手性合成。

The thesis was designed to optimize the cultures of producing D-LA bySporolactobacillus sp. and analyze the effects on fermentation in order to produceD-LA effectively.D-lactic acid is considered to be a very important chemical compoundas a chiral material or intermediate in organic synthesis. D-LA is a prosoma of manychiral compounds with applications not only in the pharmaceutical and cosmetic industry but alsoin highly efficient and lowly toxic pesticide and herbicide.

本研究的目的是通过对芽孢乳杆菌发酵工艺的研究，建立一条产物光学纯度高、工艺简单，成本较低的D-乳酸生产路线。D-乳酸是重要的手性中间体与有机合成原料，是多种手性物质的前体，广泛应用于制药、化妆品和高效低毒农药及除草剂等领域的手性合成。

Preparation of pyruvate can be achieved by chemical catalytic synthesis, microbial fermentation and biocatalysis.

丙酮酸的生产方法主要有化学催化合成法、微生物发酵法和生物催化法。

This thesis is aimming at the synthetic study of Cephalotaxine, construction of Stenine skeleton and consists of the following three parts:In Charpter 1 the isolation, chemical structure identification, biological activities of Cephalotaxine was described and reviewed total synthesis of Cephalotaxine via spiro compound.

本论文以三尖杉碱的合成及百部碱骨架的构筑为研究核心，共分为以下三部分内容。

After chemistry and ~1H-NMR,~(13)C-NMR、GC-MR、UV, IR Spectral analysis instrument synthesis appraisal compoundⅠ,Ⅱ,ⅢRespectively isβ-Sitosterol, oleanolic acid , ursolic acid; compoundⅣ,The structure is being appraised. CompoundⅠand compoundⅢare discovered for the first time from Radix Rosa davurica pall. Through pharmacognosy research and the chemical composition carries on the system to the root of Rosa davurica pall.

经化学及~1H-NMR、~(13)C-NMR、GC-MR、UV、IR等光谱分析仪器综合鉴定化合物Ⅰ、Ⅱ、Ⅲ分别为β-谷甾醇、齐墩果酸、熊果酸，其中化合物Ⅰ和化合物Ⅲ为首次从山刺枚根中发现。

Emphasis on reaction mechanisms, synthesis, stereochemistry, as well as chemical and spectroscopic methods of analysis.

课程重点在反应机构、合成、立体化学、化学分析及仪器分析方法。

For each group of compounds, their nomenclature, chemical physical properties, synthesis,reactions, and stereochemistry are taught.

针对每一类别的有机化合物，教导内容包含命名原则、合成方法、化学与物理特性、反应机制及立体结构。

Possessing the characters of high hardness, low density and inert chemical properties, boron suboxide is the best candidate for super-hard films. The synthesis technique of boron suboxide film is hotpressing.

硼的亚氧化物是坚硬薄膜材料的最佳侯选物之一，具有高硬度，低密度，稳定的化学性质及很多有意思的物理性质等特质。

Being a subproblem of process systems engineering, synthesis of operating procedures for chemical processes has great theoretical significance and practical value.

作为过程系统工程领域的一个子课题，化工过程操作程序的设计有着重大的理论意义与实用价值。

Phenyl or m -tolyl selenoamides reacted with functionalized α-haloacetic acid in 1∶1 or 1∶2 molar ratio with no catalyst in various alcohols to undergo a selenium transfer reaction. This reaction in dif-ferent molar ratios furnished the same C—Se—Se—C coupling products with a special structure bis diselenide. A new and facile method for synthesis of such bis(alkoxycarbonyl-methyl) diselenides with the advantages of mild reaction conditions, high yields, easy availability of starting materials and good chemical selectivity was provided.

芳基硒代酰胺与氯乙酸在各种醇中无催化剂下以1∶1和1∶2的比例投入，发生硒转移反应，不同原料投入比下的反应生成了同一种C—Se—Se—C偶联产物——具有多功能团的二烷氧羰基甲基二硒醚，提供了一种新的合成二烷氧羰基甲基二硒醚的简便方法，且反应具有条件温和、产率高、原料易得和选择性好等优点。

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