查询词典 sulfuric acid

The traditional production process for biurea is sulfuric acid method,in which such problems as serious corrosion of equipment,difficulty at sewage treatment,and expensive environmental protection exist.

传统的硫酸法联二脲生产工艺存在设备腐蚀严重、污水处理难度大、环保费用高等问题。

The results showed that more effective measures are the blading pierced seeds and sulfuric acid soaking seeds 50min.

结果表明：刀片破皮和98%浓硫酸浸种50min效果较好，处理后种子发芽率分别达到98.0%和98.7%。

Central composite design/response surface methodology can be used to evaluate the feasibility and applicable conditions of the anthrone-sulfuric acid method to determine the polysaccharide isolated from Bletilla striata using Dextron T20 as a standard substance.

星点设计－效应面法可以用于评估以葡聚糖T20为标准品、蒽酮－硫酸法测量白芨多糖含量的可行性，并优化测量含量的适用条件。

Objective: To optimize the condition of anthrone-sulfuric acid method to determine the polysaccharide isolated from Bletilla striata by central composite design/response surface methodology.

目的：采用星点设计－效应面法(Central composite design-response surface methodology， CCD-RSM)，考察蒽酮－硫酸法测量白芨多糖含量的可行性和适用条件。

Results: The optimum conditions of determination: the volume ratio of the polysaccharide and anthrone-sulfuric acid is 1:2; the time of color hydrolysis is 8.00 min; the cooling time at room temperature is 15.00min. On this condition, there was favorable correlation between the absorption of Dextron T20 and polysaccharide of Bletilla striata.

结果：当多糖溶液与蒽酮试剂比例为1：2，水解显色时间8.00min，室温冷却放置15.00min时，测定葡聚糖T20和白芨多糖含量具有良好的相关性。

A decatalytic spectrophotometric based on a copper catalyzed redox reaction between potassium peroxydisulfate and bromcresol purple has been developed for the determination of trace copper in the percent of sulfuric acid.

在酸性介质中，以K2S2O8为氧化剂，溴甲酚紫为指示物质，Cu强烈阻抑K2S2O8氧化溴甲酚紫褪色反应，褪色反应程度在一定范围内随Cu浓度增大而降低。

Some countermeasures are taken to solve the problems, such as the smaller pipeline diameter (108 mm), poorer water quality, more serious scale deposit and lower pump capacity, which are resulted from the panel cooler for concentrated sulfuric acid (32m2) instead of the calandria type cast-iron cooler for enlarging productive capacity (from 20kt/a to 40kt/a).

在硫酸装置扩能时(由20 kt/a改为40 kt/a)，选用板式浓硫酸冷却器(32m2)代替原铸铁排管冷却器。使用中发现管路直径偏小(￠108mm)，水质差结垢严重，硫酸泵扬量选择偏小等问题。提出改进措施。

Electrochemical oscillation of lead electrode in sulfuric acid has been explored with in-situ ellipsometry.Effects of improvement of electrodes properties are affected by increase or decrease of surface temperature of the samples badly during ion implantation. Some theories and methods on substance diffusion transfer have been applied to calorifics to obtain mathematical relation between the surface temperature on the samples and operation time during ion implantation.

掠射式椭圆偏振方法是本论文提出的一种全新的研究方法，为验证这种现场研究方法的可行性，本论文选择了几个用其它方法研究较为成熟的电化学体系并结合本论文研究的化学电源体系，以掠射式椭圆偏振技术进行研究，提出了改良镍电极、锌电极、铝电极和铜电极性能的具体措施或者理解这些电极表面性质和涉及它们的电极过程的实验依据，为使用这些电极的化学电源性能的提高奠定了基础。

Some coumarin derivatives are synthesized through Pechmann reaction with catalytical amount of sulfuric acid.

在催化量硫酸的存在下，用微波辐射进行Pechmann反应，制备香豆素衍生物，获得中等至良好的产率。

Octachlorodipropyl ether was extracted from tea samples using n-hexane-acetone(22∶3,V/V),purified with celite 545-sulfuric acid(1g-0.4mL) using hexane as an eluent.

茶叶样品用正己烷-丙酮(22∶3，V/V)提取，经硅藻土545-浓硫酸(1g+0.4mL)净化，以正己烷洗脱，GC-ECD检测，外标法定量。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。