查询词典 reaction

Preparation of the lateral chain-4-benzyloxy-3-hydroxy butyronitrile is introduced as the substrate, the REFORMATSKY reaction is performed, then obtains the dicarbonyl ester, in the structure of which containing a chiral hydroxyl group, then performs the chiral reduction, take off the benzyl group after the protection reaction with acetonylidene,then obtains the lateral chain by oxidation.

手性侧链醛的合成：采用-4-苄氧基-3-羟基丁腈作为底物，通过REFORMATSKY反应缩合得到含有手性羟基的二羰物酯，再手性还原，丙酮叉保护后氢解脱苄，最后氧化得到侧链醛。

The E-TOF will also be feasible and practical to assist chemists in screening the optimal reaction condition or evaluating the overall efficiency of different catalytic systems for a specific asymmetric reaction.4.For the first time,we explored chiralγ-hydroxy-α,β-acetylenic esters,which were prepared via asymmetric alkynylation,as key intermediates to the synthesis of chiralγ-butyrolactones. This convergent and enantioselective approach to chiralγ-butyrolactones is practical and easily handled with protecting group free.

这一概念包括反应产率、对映选择性、配体用量以及反应时间四个重要反应参数，不仅适用同一反应不同催化体系的横向综合性评价，而且适用于某一特定反应催化体系的优化过程，有助于研究人员选择最佳的反应条件。4、我们发展了以手性γ-羟基-α，β-炔酸酯为关键中间体完成了手性γ-丁内酯类天然产物的对映立体选择性全合成，该关键中间体能够以我们的催化体系方便的对映选择性合成，之后的官能团转换方法成熟，易于操作，无需进行繁琐的官能团保护和脱保护过程，绿色经济。

The ingredients defining the propellant are transformed adiabatically and irreversibly to reactions product constituents in the amounts fixed by equilibrium relations, chamber pressure, and mass balance at a reaction temperature fixed by the available energy of reaction.

成分确定推进剂转化adiabatically和不可逆转的反应，产品在功能组别的金额由平衡关系，商会的压力，和质量平衡，在反应温度固定由现有的能源反应。

The results are as following:(1) The relationship between verb and its direct object affects the ASDs\' reaction times significantly;(2) The same as on mentally retarded group, the sentence continuity, decided by the combining of verb and following noun/adject, has a significant influence on ASDs\' reading process and reaction time, indicating that the vocabulary information of verb is involved at the early stage of ASDs\' sentence reading.

研究结果表明：(1)动词和直接宾语之间的搭配关系显著影响自闭症组被试的反应时；(2)与弱智组一样，动词与后接名词和形容词所形成的句子的可继续性显著影响自闭症组的阅读过程和反应时，表明动词的词汇信息在自闭症谱系障碍学生句子分析早期便参与句子的分析理解。

When AlCA reacts with HPAM, the lower the pH value of AlCA, the faster the rate of gelling reaction. At a certain pH value, the smaller the ratio of /, the slower the rate of the gelling reaction.

结果表明，柠檬酸铝在碱性条件下的稳定性、热稳定性及室温下的放置稳定性均随／的减小而提高，pH值过高或过低的柠檬酸铝均不能长期稳定存在。

The experiment proves the reaction of glue of enzymatic catalysis bee is an oscillation reaction, accord with human body to draw the rule to alimental.

实验证实酶催化蜂胶的反应是一个振荡反应，符合人体对食物的吸收规律。

The effects of reaction time, temperature, alkalic degree and the feed ratio on the hydrolysis reaction were investigated by means of the orthogonal design method. And the optimum operating conditions were got. Polyacrylate sodium was prepared under the optimum conditions.

利用正交设计，讨论了反应时间、温度、碱浓度、投料比等因素对水解反应的影响，获得了优化的水解反应条件，并在最优化的条件下制得聚丙烯酸钠。

Experimental results showed that such as pH value, charging ratio and method, reaction temperature and reaction time, concentration of material, assistflocculant and resting period can all influnce the alkalization degree of product.

结果表明pH值、加料方式、反应温度、反应时间、原料浓度、助聚剂、存放时间等均会影响盐基度。

1A series ofω-alkylmercapo acid were synthesized by two methods:one involved the reaction of the appropriateω-bromoalkyl acid with mercaptide under the presence of base;the other method was used only for the long alkyl compound by the reaction ofω-alkenyl acid and alkanethiol in the presence of AIBN.

正是基于以上考虑，本论文探索了合成下沿带有硫醚官能团，而上沿带有偶氮官能团的杯[4]芳烃衍生物的方法，进行了以下研究： 1采用ω-溴代羧酸和烃基硫醇在碱性条件下发生反应，或由ω-烯基羧酸和硫醇在AIBN的存在下反应，得到了ω-硫醚羧酸，使用氯化亚砜将羧酸转化为酰氯。

Advancing the temperature can increase its molecular weight, the best reaction temperature is 60℃, following by IR, the mechanism of HC1 is the hydrolyzation of alkoxy in 1 hour, and then condensation reaction.

升高温度有利于生成大相对分子量的聚合物，其水解缩合的最佳温度为60℃，通过IR对反应物的跟踪，在水解缩合过程中盐酸作为催化剂先是烷氧机硅烷的水解作用，1小时内就可以完成，之后再发生缩合反应。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。