查询词典 chemical method

Titration is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of a known reactant.

滴定是定量化学分析中常见的实验室方法，用于测定已知反应物的未知浓度。

In the contaminated lard sample, 6 organic compounds have been thus identified to be the raw materials or byproducts in the production of organic tin compounds. Based on the identified contaminants, it can be postulated that the chemical structure of the organic tin compound is dibutyltin-bis-(2-isooctyl thioacetate). The method is simple and precise, and has not been reported in the local literature.Keywords Organic tin compound, Lard, SPME－GC－MS

经过摸索研究，采用固相微萃取方法富集挥发性杂质，直接注入色谱中，经色谱分离，质谱测定，确定了杂质的结构，由杂质成分推断生产有机锡所用的原料，然后判断合成路线，最后确定有机锡的结构，从有毒猪油中鉴定出2－巯基醋酸异辛酯、双（2－醋酸异辛酯）二硫、双醋酸异辛酯硫醚等6种与有机锡有关的杂质，并与相应的有机锡工业品对照，发现工业品中也含有这些杂质，与其合成过程的原料及副产物相符，从而确定有机锡化合物为二硫代醋酸异辛酯二丁基锡。

The limit conductivity of strong electrolyte solution was determined with classical electric chemical experiment method according to Kohlrausch's Law of Independence Migration of Ions,and indirectly the limit molar conductivity of weak electrolyte solution was calculated.

依据Kohlrausch离子独立运动定律的基本原理，采用经典的电化学实验方法，测定强电解质溶液的无限稀释摩尔电导率，间接求出弱电解质溶液的无限稀释摩尔电导率。

Inhibitor is a chemical species or admixture, which exists in the medium and can prevent from corrosion or retard corrosion. It is an effect method to use inhibitor to prevent metals and its alloys corrosion in environmental medium.316L stainless steel is an austenitic stainless steel consisting molybdenum, and its corrosion resistance was improved much than normal stainless steel.

缓蚀剂是一种以适当的浓度和和形式存在于环境中时，可以防止或减缓腐蚀的化学物质或几种化学物质的混合物，合理使用缓蚀剂是防止金属及其合金在环境介质中发生腐蚀的有效方法。

The chemical formula of the phosphor is SrMoO4:Eu. The method comprises the following concrete steps that: according to the molar ratio of 2:100:100 to 4:100:100, Eu2O3, MoO3 and SrCO3 solids are put into a mortar to be ground and fully mixed; an obtained product is placed in a crucible in a muffle furnace to be roasted for 3 to 4 hours at the temperature between 500 and 700 DEG C, and then a needed product can be obtained.

该荧光粉的化学式为：SrMoO 4 ：Eu 3 ，具体步骤为：将Eu 2 O 3 ，MoO 3 和SrCO 3 固体按照摩尔比为2∶100∶100～4∶100∶100的比例置于研钵中研磨，使其充分混合；将所得产物置于坩埚内放在马弗炉中于500℃～700℃的温度下焙烧3-4h，即得所需产品。

Thirdly, explosion ventings were simulated numerically with the constructed method since the state of chemical balance of the premixed methane-air system in a closed vessel.

接着，利用以上方法模拟了三种当量比的甲烷-空气预混气体在燃烧达到化学平衡后的泄爆过程。

The result showed that chromatogram peaks were summated,peak area increased and two new peaks were found.It suggested that the composition dissolution of RP was increased with the addition of RAT,chemical changes may be occurred after compatibility. Established the HPLC analysis method forα-asarone in RAT and researched the content change ofα-asarone after compatibility.

发现配伍后色谱峰具有加和性，峰面积增加，有两个新峰产生，提示石菖蒲能使远志中的化学成分溶出度增加，两药配伍后可能发生了复杂的化学变化；建立石菖蒲中α-细辛醚的HPLC分析方法，研究配伍远志后α-细辛醚的含量变化。

It is impossible to establish one method to applying for all of pesticides and samples, so different methods are introduced to analysis different categories of pesticides, according to different physico-chemical properties.11 Organochlorine Pesticides are detected by GC-ECD and extracted with 50ml acetone and 100ml petroleum aether in Solxhlet's extractor clean-up with oil of vitriol.

农药种类繁多，结构各异，建立一种方法适用于所有农药和样品难度极大，本文将常用农药按分子结构分为四类分别建立检测方法：采用索氏提取器，丙酮/石油醚(50：100，V：V)混合溶剂提取、磺化法净化、GC-ECD检测研究了11种有机氯农药在蔬菜、水果、粮食中残留，结果显示11中有机氯农药在五种样品上的5次重复平均回收率，从添加0.005到2.000mg/kg的回收率范围为92.4%—103.7%，平均回收率大于80%，变异系数范围在1.16—9.16%之间。

Oil-containing poly microcapsules were prepared by simple coacervation followed by the chemical cross-linking of coacervated PVA membrane with glutaric aldehyde through phase separation method.

本实验使用聚乙烯醇Poly为壳材，以香精油为核材，利用相分离原理，以简单凝胶法，以戊二醛为交联剂进行微胶囊包覆。

Th is method has also other advantages such as narrow size distribution of particles, no chemical reductants and the possibility to prepare bimetallic nanoaggregates.

该方法还具有颗粒度分布均匀、无须添加化学还原剂以及可以制备纳米合金粒子等优点。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。