查询词典 reaction rate

The effect to rate of production of the reaction active of different alkaline earth, the reaction efficiency of different low-carbon alcohols and reaction time were investigated.

考察了不同碱土金属、不同低碳醇及反应时间对醇盐产率的影响。

The results indicate that the optimized sulfonylation reaction time is 4 h, the materiel rate of chlorosulfonic acid and 2-chloroimidazo[1,2-α]pyridine is 1.2 : 1, with ethylamine the yield increasing from 15.4% to above 70%; the optimized ammonolysis reaction time is 3 h and the reaction temperature is 27℃, with the acetonitrile yield increasing from 60.1% to above 79.6%.

实验结果表明，磺酰化反应的最佳反应时间为4 h，氯磺酸与2-氯咪唑并[1，-α]吡啶的用量比为1.2：1，加入三乙胺可将收率由15.4%提高到70%以上；氨解反应的最佳反应时间为3 h，反应温度为27 ℃，加入乙腈可将收率由60.1%提高到79.6%；方案经改进后，总反应时间缩短3 h，收率提高了5.5%。

On the basis of HPLC analytical results, a reaction mechanism between chlorine dioxide and phenol had been proposed. The rate control step in the process of reaction was studied by using ab initio method. Opmital geometry of every species in reaction was caculated by the available gratient optimum software. The result of harmonic vibrational frequencies indicated that phenolate radical was a stable intermediale product.

根据对ClO〓氧化苯酚后的高压液相色谱图，提出了ClO〓与苯酚氧化反应的机理，并对反应机理中的速度控制步骤进行量子化学理论剖析，利用梯度优化软件计算了参加反应物种的平衡几何构型，振动频率分析的结果表明：酚氧自由基是稳定的反应中间体，利用ab initio计算软件计算了参加反应物种的总能量，酚盐负离子中的氧原子电荷密度，布居数和前线轨道。

Methods:all patients with ptb were received ppd test,according to the outcome of test,the cases were divided into negative reaction group,positive reaction group and strong positive reaction group.all patients were received antituberculotic treatment.the rate of sputum corersion,cavity closing up and focus absorption were observed.

将所有列入观察组的肺结核患者进行ppd试验，并根据皮试结果表现分为阴性反应组、阳性反应组以及强阳性反应组，分别给以抗结核治疗，观察不同ppd反应患者的痰菌转阴速度、空洞闭和速度以及疗程结束时病灶的吸收速度。

The analysis of thermal behavior and chemical structure show that the three main reactions do not initiate simultaneously. Dehydrogenization and cyclization reactions begin at the initial stage of stabilization, while oxidation reaction takes place on the precondition of cyclization reaction. Cyclization reaction has induction period that is influenced by temperature and heating rate.

热分析和化学结构分析的结果表明，预氧化过程中的三大主要反应并非同时进行，脱氢反应和环化反应从预氧化初期开始，而氧化反应需要以环化反应为前提条件，随后进行；环化反应具有一定的诱导期；在氧化性气氛中，首先发生脱氢反应，氧对环化反应起到了阻碍作用，使整个过程顺利可控。

Isoamyl isovalerate was synthesized through esterification reaction by using isovaleric acid and isoamyl alcohol as raw materials and nano-H4SiW12O40/SiO2 as catalyst, the influencing factors in the reaction were studied, and the results showed that the esterification rate could reach 98.6 % under the conditions of the ratio of alcohol-acid 1.4∶1, the use level of catalyst 5 %, and the reaction time 1.5 h.

以纳米复合钨硅杂多酸为催化剂，异戊酸和异戊醇为原料，通过酯化反应合成苹果油，对酯化反应的影响因素进行了研究，结果表明，在醇酸物质的量比为1.4∶1，催化剂用量5%，反应时间1.5h的条件下，酯化率可达98.6%。

To get more insight into the mechanism and kinetics of the RAFT process,it would be helpful to build a small molecular model reaction mimicking the RAFT process but free of a chain-propagation event. We hereby propose a model cross reaction between dithioester and alkoxyamine as a probe of the RAFT process,in which the alkoxyamine plays the role of the radical source.The generating rate of the transient alkyl radical and the nitroxyl radical can be described by the law of persistent radical effect.Thus,the advantage of the model cross reaction is that it affords a radical concentration determined by the known equation of the persistent radical effect.

为了更深入的理解RAFT聚合过程，我们构建了一个模型反应：即由烷氧基胺与双硫酯进行交换反应，烷氧基胺均裂产生的烷基自由基将会向双硫酯进行链转移，双硫酯的引入对纯烷氧基胺分解动力学造成的影响可以提供RAFT过程的许多信息。

Firstly, the reaction thermodynamics was analyzed. Then, the reaction mechanism was studied, and the results are as following:① Ca moves to the surface of Dy〓O〓 by vapor phase;② Dy〓O〓 reduced to Dy by Ca is fast;③ Dy moves to the Fe surface mainly by vapor and various Dy-Fe alloys are produced gradually;④ The forming process of DyFe〓 may be described by Contracting Core Model;⑤ The rate-controlling step of the reaction is the Dy diffusing toward contracted and nonreaction nuclear center Fe.

首先考察反应的热力学可能性；其次探讨反应机理；通过实验确定：①Ca主要以气态形式迁移到Dy〓O〓表面参与反应；②Dy〓O〓被Ca还原为Dy的速度很快；③Dy主要以气态形式迁移到Fe表面逐级生成Dy-Fe合金；④DyFe〓的形成过程可以应用收缩核模型来描述；⑤Dy通过DyFe〓产物层向缩小的未反应核中心Fe的扩散是反应的控速步骤，通过动力学计算确定：还原扩散反应的表观活化能E〓=45kJ/mol。

Adopted with the study mode of Reaction Times and the technique of Event-related Potentials, the paper compared the difference of the reaction times, accuracy rate,latency,amplitude of ERP components of athletes and undergraduate students during the process of choice reaction to stimuli which were presented at different field of vision, in order to explore the variety characteristics of brain nerve activity of spatial perception of athletes.

采用反应时研究范式和事件相关电位技术，通过比较运动员与普通大学生对不同视野刺激进行知觉选择反应的反应时间、反应准确率及所诱发的ERP成分的潜伏期和波幅的差异，来揭示对抗性项目运动员空间知觉的脑神经活动变化特点。

Because the techniques of the biochemical waste treatment are very important, the techniques of the cultivation of the microorganism have received more attention in recent years. A study is conducted to analyze the steady states and dynamic bechavior of the reactions of the cell-substrate and the prey-predator interaction in two chemostats in series. For the reaction of cell-substrate in two chemostats in series, if the specific growth rate of the Monod model is used for the cell , there are three types of steady states for this reaction system. These three types of steady states and stability are analyzed in detail. The dynamic behavior of this reaction system is analyzed by the numerical method and computer graphs. The results show that the dynamic behavior of this system consists of stable steady states.

由於生物废弃物的处理技术相当重要，故最近几年来微生物的混合培养技术深受大家的重视，本研究实施菌类－基质(Cell-Substrate)和被捕食者－捕食者(Prey-Predator)相互作用之生化反应在两个生化反应槽串联之稳定状态和动态分析，对於菌类－基质之生化反应，若以Monod模式来表示菌类之比生长速率，则此两个生化反应槽串联之反应系统共有三种型态之稳定状态，本研究对此三种型态之稳定状态和稳定度作深入的分析，对於此反应系统之动态行为，则由电脑运用数值分析的方法及电脑绘图进行分析工作，动态分析的结果显示此生化反应系统之动态行为，以稳定之稳态为主。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。