查询词典 distillation method

Coumarin in melilotus was extracted in the method of steam distillation, and the content of coumarin in product was less than 2% and plentiful tar as the by-product was found at the same time.

采用水蒸气蒸馏法对草木樨中的香豆素进行提取，其提取物中香豆素的含量不到2%，并伴有大量的焦油产生。

An improved method of synthesizing trimethyl orthoformate through azeotropic distillation by taking sodium methoxide in methanol and chloroform as raw materials has been presented by the author.

摘 要：介绍了以甲醇钠甲醇溶液与氯仿为原料，采用共沸蒸馏法制备原甲酸三甲酯的改进工艺。

A method for the determination of phenol and catechol in tobacco leaf by high performance liquid chromatography with methanol and 0.05 mol/L of monopotassium phosphate as mobile phase at a flow rate of 0.5 mL/min was described. Phenol and catechol were extracted from tobacco sample by distillation and solid phase extraction with Sep Park C 18 cartridge.

引 言挥发酚是烟草中一类重要的成分，它在烟草燃烧时直接进入烟气，大多有不好的气味，而且很难被掩盖；特别是苯酚和儿茶酚对呼吸系统有腐蚀作用和助癌作用，近年来逐渐引起了烟草化学工作者的注意〔1〕。

Objective:To study the extraction technology of paeonol from Cortex Moutan,and improve the extraction method of steam distillation with ultrasonic assistance.

目的：对牡丹皮中丹皮酚的提取工艺进行研究，考察超声辅助水蒸气蒸馏提取的效果，改进提取工艺。

A new method is presented for synthesis of organosilicon compounds directly from precipitated white carbon black by reduced pressure distillation.

该文研究了以沉淀白炭黑为原料，采用减压蒸馏法直接合成六配位体有机硅化合物的新方法。

The method comprises heating up the lactic acid solution to gasify at 150-200 degree C, mixing the obtained mixed vapour of lactic acid and water with the carrier gas, entering into gas-solid catalytic reactor to get the reaction product gas by the action of a modified Y zeolite molecular sieve catalytic agent and dewatering after heating up the mixed gas to 200-450 degree C, obtaining the propenoic acid solution through gas-liquid dissociation after cooling the reaction product gas, obtaining coarse propenoic acid products form the propenoic acid solution by gas stripping, azeotropic distillation, extraction and rectification in turns.

其特征在于将乳酸水溶液加热至150～200℃气化得到的乳酸-水混合蒸气与载气混合，将混合后的气体继续加热到200～450℃后进入气-固相催化反应器中经改性Y沸石分子筛催化剂作用脱水得反应产物气体，反应产物气体冷却后经气液分离得到丙烯酸溶液，丙烯酸溶液再依次经过气提、共沸蒸馏或萃取、精馏得到粗丙烯酸产品。

A desulfurization method is proposed for the removal of sulfur compounds from FCC gasoline by alkylation reaction of thiophenic sulfur with olefins over acid catalysts, and the higher boiling sulfur-containing products are removed by fractional distillation.

选择以噻吩的甲基取代衍生物(包括 2-甲基噻吩、3-甲基噻吩及 2，5-二甲基噻吩)与异丁烯的烷基化反应为模型反应，考察了经三氯化铝气相固载法改性的 CT175 树脂催化剂催化噻吩的甲基取代衍生物与烯烃的烷基化反应性能。

The distillation-nitration method is a new process for nitrating toluenc toTNT.

引言 TNT是近代军事上应用最广泛的猛炸药之一。

The methods of extracting and refining tellurium presently were mainly soda roasting,autoclaving in general basic solution,sulfating roasting,oxidative leaching in acid solution, solvent extraction ,emulsion liquid membrane,microbial method,electrorefining,vacuum distillation and zone melting etc.

目前分离提纯碲的方法主要有苏打粉焙烧法、碱性高压浸出法、硫酸化焙烧法、氧化酸浸法、萃取法、液膜法、微生物法、电解精炼法、真空蒸馏法、区熔精炼法等，其中电解精炼法得到的碲的纯度达到99.99%，真空蒸馏碲的纯度达到99.999%，区熔精炼碲的纯度可达99.999995%，本文综述了以上分离提纯碲的方法。

The distillation analysis, which is slow, harmful to human and would bring rather large error according to the used analyzing method, was used before in Coke Plant, Handan Iron and Steel Company for analysis of light benzene .

邯钢焦化厂的轻苯分析以往采用的是蒸馏分析法，其速度慢，分析时受方法的限制误差很大，且对人身体造成很大伤害。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。