查询词典 reaction rate

Since the dismutation of superoxide radicals by SOD is a reaction that is rate-limited by diffusion and enhanced by electrostatic guidance, all these structural features may be related to GP-MnSOD's high catalytic activity: first, Lys38 may increase the effective enzyme-substrate association rate by enhancing the electrostatic gradient at its substrate channel; second, an excess of acidic over basic residues makes the negative surface potential of GP-MnSOD more larger than those of other known MnSODs. This may enhance the reaction rate by reducing futile collisions of superoxide radicals with GP-MnSOD's surface.

因此，GP-MnSOD的上述结构特征可能与GP-MnSOD的较高酶活有关：首先，Lys38增加了底物通道口的正静电势梯度，从而可能促进了GP-MnSOD的活性中心与底物的有效结合速率；其次，GP-MnSOD表面覆盖的过量酸性残基使得它比其它MnSOD在底物通道以外的蛋白表面更多地被负静电势所覆盖，这可能有效地减少了超氧阴离子与GP-MnSOD表面的无效碰撞，从而提高了反应速率。

The effect of different reaction conditions,such as catalyst concentration,molar ratio of reactants,reaction temperature,reaction time,on the coupling reaction of trioxane and methyl formate synthesizing methyl glycolate and methyl methoxy acetate using sulfuric acid as catalyst has been studied.Through the analysis for the yield of products and system pressure,and comparison with other different acidity catalysts,we considered that the activation of formaldehyde was the control step of reaction rate to the...

以硫酸为催化剂，研究了三聚甲醛与甲酸甲酯偶联合成乙醇酸甲酯和甲氧基乙酸甲酯的反应中，催化剂浓度、原料配比、反应温度、反应时间等条件对反应过程的影响，通过对产物收率和系统压力变化的分析，并结合与其它不同酸强度催化剂的对比，得到甲醛的活化是偶联反应的速率控制步骤，催化剂的酸强度决定其对甲醛的活化能力，是影响偶联反应的主要因素。

This complex reaction was phenolic electronic substitution reaction, so reaction rate was related with the positive electricity of pro-electronic reagent, as well as the form of aromatic hydrocarbons. Rates of chlorination of phenol and 2-monochlorophenol were faster in alkaline water than that in weak acid water, so 2,4-dichlorophenol and 2,4,6-trichlorophenol formation concentrations increased with the reaction time.

该复合反应属于酚类电子取代反应，反应速率与亲电子试剂的阳电性以及芳香烃的形式有关，碱性水环境中氯取代苯酚和2-一氯酚的速率要快于在弱酸性水环境；随着pH的升高，2，4-DCP和2，4，6-TCP的生成浓度也不断增加。

ELISA method was used for comparison. Results The positive rate of DIGFA in testing the serum from 50 infected rats was 96.0%(48/50). The negative rate of DIGFA in healthy rats was 100%(50/50). Cross reaction with Enteroclysis (13 samples) and Tapeworm (11 sqamples) was not observed. The cross reaction rate in 18 Strongyloidiasis rats was 5.6%. The sensitivity and specificity of DIGFA is comparable with ELISA (96.7%).

结果 用DIGFA检测广州管圆线虫实验感染鼠血清50份，其阳性检出率为96.0%，50份正常鼠血清的阴性符合率达100%，DIGFA分别检测蛲虫阳性鼠血清13份，绦虫阳性鼠血清11份和粪类圆线虫阳性鼠血清18份，前二者均为阴性，后者交叉反应率为5.6%；DIGFA与ELISA平行检测30份广州管圆线虫阳性鼠血清，两法符合率达96.7%。

The results show that this reaction proceeds in two step: 1 silylene and formaldehyde form an intermediate complex, which is a kind of exothermal reaction with no barrier; 2 the intermediate complex isomerizes to sive the product. The barrier for the second step is 51.4kJ·mol^-^1 at MP2/6-31G^*//6-31G^* level (with zero-point energies correction). In view of dynamics and thermodynamics, it is between 300～400K that the reaction will have not only larger spontaneous tendency and equilibrium constant but also quicker reaction rate.

结果表明，此反应历程由两步组成：1硅烯与甲醛生成一中间配合物，是一无势垒的放热反应，2中间配合物异构化为产物，此步势垒经零点能校正后只有51.4kJ·mol^-^1(MP2/6-31G^*//6-31G^*)；从热力学和动力学的综合角度考虑，该反应在300～400K温度下进行为宜，如此，反应既有较大的自发趋势和平衡常数，又具有较快的反应速率。

When the concentration of sulfur dioxide was fixed, the reaction rate increased separately with increasing oxygen content and water vapor content, when oxygen content was 20%, the reaction rate was the highest, while water vapor content was 444μmol/L, there was an optimum value for the photocatalytic degradation rate of heptene.

庚烯的降解速率随着二氧化硫浓度的增加而增加，最终趋于稳定。在二氧化硫浓度一定时，庚烯的反应速率分别随着氧气和水分子含量的增加而不断增大，氧含量为20%时速率最大；水分子含量为444μmol/L时速率最大。

Can induce the reaction of cleavage H atom from methyl on the ring of deactivated toluenes,such as nitrotoluene. The carbanions caused by base are the very important reaction intermediums, which determined the reaction rate and reaction effect.

该反应体系中，NaOH的加入对此催化反应起着相当关键的作用，研究表明强碱也能像温度一样促进苯环卜甲基的摘氢速度，使底物形成相应的硝基苯甲基阴离子，稳定的硝基苯甲基阴离子是氧化反应进行的重要中间体。

A new trick using Trichogramma brassicae asvectors to transmit Dendrolimus punctatus cypovirus was developed (called"Biological missiles Dp-Ⅰ") to control the Dendrolimus punctatus in the field. Sincethen, we collect the single caterpillar from both areas used Dp-Ⅰand controlled areasevery year, and A nested-PCR-based assay for the detection of those samples wasdeveloped, The results showed that the positive reaction rate of the first year is 40～70％; and second year is 30～80％, on the other hand, the positive reaction rate of thecontrolled areas are 10～40％and 10～20％.

第二章对马尾松毛虫质型多角体病毒的流行病做了初步的调查，应用巢式RT-PCR方法检测从野外释放&生物导弹Dp-Ⅰ&的林区采集马尾松毛虫单虫样本，结果发现：2006年释放&生物导弹Dp-Ⅰ&的王福店林区的松毛虫体内DpCPV阳性率为40～70％，平均阳性率为58％，相应对照区的阳性率为10～40％，平均阳性率为24％；2005年释放&生物导弹Dp-Ⅰ&的丁家畈林区松毛虫体内DpCPV阳性率为30～80％，平均值也为58％，相应对照区的阳性率为10～20％，平均值为16％。

The infection of the reaction rate of the virous monomers was reviewed respectively by the different THF dosage, TMEDA dosage, t-BuOK dosage, t-AmOK dosage and different temperature. The monomers apparent reaction rate constant was obtained.And the polymer composition at different conversion was reviewed, too.The effect of modifier and temperature on heat effect was also studied. In addition, the sequence structure and microstructure of the terpolymer was reviewed at different modifier dosage, and the structure was characterized by the ~1H—NMR.

分别考察了不同THF、TMEDA、t-BuOK、t-AmOK加入量以及聚合温度对各单体及总的反应速率的影响规律，得到了各单体及总的表观反应速率常数，求得了不同转化率下各单体在共聚物中的分布情况，同时考察了调节剂加入量对聚合温升热效应的影响规律；研究了在三种聚合体系下，通过~1H—NMR对共聚物的结构进行了表征，分别考察了不同调节剂加入量对共聚物的序列结构及微观结构的影响规律。

It is shown that the chlorinating process for fluorine-fixed calcine agreed well with the regional reaction rate model presented by Bagdasarym. The process consisted of two tandem steps, Erofeev Equation ln[ln(1a)]=lnk+nlnt was used to deal with the equation of reaction rate,the function between rate constant and temperature was k=2.7?07e125900/RT. The a...

结果表明：固氟焙砂的氯化反应动力学过程是区域反应速率模型，氯化反应过程经过了2个串联反应步骤，用Erofeev方程ln[ln(1a)]=lnk+nlnt处理反应速率，反应速率常数与温度T的函数关系式为k=2.7107eEa/RT，表观活化能Ea为125.9 kJ/mol，过程限制环节主要是界面化学反应控制。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。