反应速率

The experiment indicates: on condition that the mole ratio is 1.1:1, temperature is 90~98℃, pH is 1~2, acid adding speed is 1 drop/(2~3) second, the yield and quality of the products can get increased when reaction liquid disposed with ultrasound wave.

实验表明：在硅酸钠与钨酸钠的物质的量比为1.1：1，控温90~98℃，pH值1~2，加酸速率1滴／(2~3)s的优化条件下，用超声波处理反应液可以增加产品的产量和质量。

The rate of TSR in geologic settings is limited by temperature and activation energy .

地质条件下热化学还原反应的速率受温度和活化能的制约。

This primary conversion of urea to unstable ammonium carbonate occurs very quickly near the soil surface The following equation illustrates the process

尿素主要在土表转化成不稳定的碳酸铵，转化速率很快，可用以下反应式表示

Apha amylase was difficult to bind with the substrate, ther fore the hydrolysis rate decreased with time.

此外，当酶水解发生到一定程度，淀粉分子链长度变得很短。alpha淀粉酶与酶作用物的结合较难，因此水解速率随着反应的进行时间下降。

After oscillating the operation parameters, the bimodal molecular weight distribution of polyethylene was generated.

通过模拟计算，分别考察了氢气、乙烯、共聚单体进料速率和反应温度的振荡操作对聚乙烯分子量分布的影响。

A three-electrode system composed of TiO2/Ni as the working electrode, porous nickel as the counter electrode and saturated calomel electrode as the reference electrode was used for the photoelectrocatalytic degradation of sulfosalicylic acid under anodic bias potential.

建立了以刮浆工艺制得的TiO2/Ni为工作电极、泡沫镍为对电极、饱和甘汞电极为参比电极的光电催化反应体系，研究了在磺基水杨酸的光电催化降解过程中，外加电压和溶液PH值对降解速率的影响。

In the batch reaction with high ratio of substrate to catalysts, the rate ?controlling step was determined by measuring the concentration variation of produced L-alanine in solution.

在近似无限浴的条件下，通过测量间歇拆分反应产生的L-丙氨酸的浓度变化规律，判断反应过程中的速率控制步骤。

In the present dissertation, a surfactant-templated mesoporous silica molecular sieve with high pore volume, high porosity and narrow bimodal mesopore size distribution was synthesized for the first time in a reaction system, which was used usually in the synthesis of mesoporous MCM-41 molecular sieves, by a judiciously controlled two-phase sol-gel processing under basic conditions.

在本论文中，我们通过对一个通常用于制备介孔MCM-41分子筛的反应体系中正硅酸乙酯水解与缩合反应相对速率的精确调控，首次在弱碱性体系中合成了一种具有高孔隙率、大孔体积和双介孔孔分布特征的新型二氧化硅分子筛材料，简记为BMS，并对BMS二氧化硅分子筛中双介孔结构形成的原因及各种可能对其结构和性质产生影响的合成因素如Ammonia／silica摩尔比、组分浓度的变化、表面活性剂烷基链长度的调节、辅助有机物均三甲苯的引入、催化剂的结构和性质、溶剂和助溶剂的极性和用量、老化和干燥条件的变化及合成后水热处理等，利用不同的测试手段如XRD，SEM，TEM，〓Si MAS NMR，TG-DTA，N〓吸附测试等进行了系统的表征研究。

The esterification reaction and itsinfluencing factors of hexanoic acid with n-butanol, catalyzed by lipaseNovozym100T, were studied in water-in-oil microemulsions formed by alkylpolyglucoside C_(12)G_(1.50)/n-butanol/cyclohexane/water system.

研究发现，十二烷基聚葡糖苷C_(12G_(1.50)／正丁醇／环己烷／H_2O体系形成的油包水微乳液中，脂肪酶Novozym100T催化正己酸和正丁醇的酯合成反应，反应初始速率V_0随正己酸的初始浓度C_~0增大而增大；随正丁醇的初始浓度C_~0的增大而减小，后V_0进入一&坪区&。

The following main results are obtained: The TiO_2 photocatalyst with small crystallite size, high surface area, narrow and uniform pore size distribution, and microporous frameworks could be prepared out by applying MW radiation in the preparation process. The microwave-induced fluorescence technique verified for the first time that microwave enhanced the formation rate of hydroxyl radical, leading to the increase in the photocatalytic efficiency. Compared with the conventional catalyst, TiO_2 prepared by MW dielectric heating owns a higher UV absorption ability, and its optical absorption edge and photovoltaic response are shifted toward the short wavelength region, resulting in increase of photooxidation efficiency. The photocatalytic conversion and the mineralization ratio of acetaldehyde are increased respectively by 30% and 40% over the TiO2 prepared by MW radiation when compared to the TiO2 prepared by the conventional heating. For the MW-assisted photocatalytic reaction over the MW-prepared TiO2, production of hydroxyl radicals is enhanced by 22.5%, and the photocatalytic conversion is accordingly increased by 20%. Similarlly, applying MW also increased the photocatalytic conversion and the mineralization ratio of acetaldehyde over TiO2/Al2O3 sample.

论文得到如下主要结果和结论：(1)微波介电加热TiO_2 溶胶可得到晶粒度小、光催化活性高、比表面积大和孔径分布窄而均一，且微孔发达的TiO_2光催化剂；在溶胶干燥处理过程中微波可使催化剂表面缺陷增加，进而导致光催化反应过程有更多的活性羟基自由基产生；(2)微波制备能显著增强TiO_2 样品的紫外光吸收率，并使其光吸收和光伏响应阈值发生蓝移，从而提高TiO_2的氧化还原能力；(3)与常规加热法所制TiO_2比较，微波法制备的TiO_2对乙醛的光催化降解转化率提高30%，CO_2生成率提高40%以上；(4)与未加微波辐射时相比，发现在光催化反应过程中施加微波，TiO_2 的羟基自由基生成速率提高了22.5%，相应CH_3CHO 光催化降解转化率提高了20%；对Al_2O_3/TiO_2催化剂，CH_3CHO 光催化降解转化率甚至提高了33%，同时CO_2 的生成率也都大幅度提高；(5)微波辐射可改变光催化降解乙醛的产物分布，推断施加微波时乙醛光催化降解按照羟基自由基引发的链式反应机理进行，微波&非热效应&起主要作用。

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％。