氯乙酸

P chlorophenoxyacetic sodium was synthesized by p chlorophenol with 2 chloroacetic acid in the 20% hydroxide sodium aqueous solution.

采用一步法由氯乙酸与对氯苯酚在氢氧化钠质量分数为 0 2的水溶液中的反应制得。

When the molar ratio of 2 chloroacetic acid∶ p chlorophenol is 1.25 and pH=5～7 at 104 ℃ reaction for 20 min in the 20% NaOH solation,the yield of PCPA can be reached 90%.

氯乙酸∶对氯苯酚为 1 2 5 ，质量分数为 0 2的氢氧化钠溶液中，pH值在 5～ 7之间，温度在 10 4℃左右为宜，反应时间为 2 0min ，PCPA收率为 90 3%。

Production technology of synthesis of allantoin are reviewed, including glyoxal oxidation, electrochemical synthesis, calcium glyoxylate synthesis, dichloroacetic acid synthesis, acetochloral method, and oxidative decarboxylation.

评述了乙二醛氧化法、电化学法、乙醛酸钙法、尿素三氯乙醛合成法、尿酸二氯乙酸法和尿酸氧化脱羧法等合成尿囊素的各种工艺。

By single factor experiment,experiment studied on the effect on the dosage of NaOH、CHPTMA、sodium chloroacetate 、temperature and time to reaction.

并通过单因素实验讨论了NaOH用量、氯乙酸钠用量、3-氯-2-羟丙基三甲基氯化铵用量、反应温度和反应时间等对合成反应的影响。

Production technology of synthesis of allantoin are reviewed, including glyoxal oxidation, electrochemical synthesis, calcium glyoxylate synthesis, dichloroacetic acid synthesis, ace-tochloral method, and oxidative decarboxylation.

评述了乙二醛氧化法、化学法、醛酸钙法、素三氯乙醛合成法、酸二氯乙酸法和尿酸氧化脱羧法等合成尿囊素的各种工艺。

The difficulty of route is the refinement of products. There is a lot of sodium chloride in solution. In order to refine the glycolic acid, the methods of vacuum distillation and organic solvent extraction are adopted.

水解合成后得到的是羟基乙酸的水溶液，其中含有大量的氯化钠和少量未水解的氯乙酸及其它杂质，采用减压蒸馏及有机溶剂萃取方法进行精制是比较适宜。

An coupling apparatus with a chlorination reactor and a melt crystallizer was built,which was used in chlorination of acetic acid and separation of monochloroacetic acidby crystalliza- tion at the same time.

用氯化反应与熔融结晶耦合装置，进行乙酸氯化与产物氯乙酸的结晶分离，避免了 MCA 的深度氯化，从而提高了 MCA 的收率。

The extraction of Pr3+was studied by using heptane containing bis(2-ethylhexyl)phosphinic acid in sodium perchlorate,chloroacetic acid and citric acid medium ,respectively.

研究了二(2-乙基己基)膦酸(PIA-8)的庚烷溶液分别在高氯酸钠、氯乙酸、柠檬酸介质中对Pr3+的萃取。

The distillation column with a single photochlorination reactor was built in this paper, which is used in the laboratory study. In light initiation, the semi-continuous operation was applied to study the influence of the chlorine flow, the reflux and the height of the packing on photochlorination of acetic acid. Crude MCA with a purity of 90% or more was attained and the feasibility of this technology was proved.

本文建立了适合实验室研究的背包式光氯化反应精馏耦合装置，采用半连续操作的方法，在光引发条件下，考察了氯气流量、回流量和填料高度对乙酸光氯化反应的影响，得到了含量达90％以上的氯乙酸粗品，证实了工艺的可行性。

The biogenic amines in test samples were extracted by 10% trichloroacetic acid and then derived with benzoyl chloride. The HPLC analysis for the samples were conducted as the following condition: mobile phase was a gradient elution program of methanol and water, the flow rate was 0.8 mL/min.

用10%的三氯乙酸提取样品中的生物胺，采用苯甲酰氯衍生处理后，以甲醇/水为流动相，进行梯度洗脱，流速0.8 mL/min，紫外检测器波长为254 nm。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。