查询词典 fractional distillation

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。

After the comparation with the experimental results of these four catalyzers,we declare that C-4 is a catalyzer of good catalytic activity and good recovery ratio.The mixed oil抯 recovery ratio is up to 71.46%,65.OO% and 50.OO%.After fractional distillation gasoline and diesel come up to 90 and 0抯 standard by the test of Kunming Product Quality Inspection Bureau.

将这四种催化剂的实验结果进行对比分析，判定C-4是一种裂化活性好、油品收率高的催化剂，在C-4 催化剂的作用下，三种原料的混合油出率分别达到71.46％、65.00％、 50.00％，混合油分馏出的汽油、柴油经昆明市产品质量监督检验所检验，分别达到90号和0号的标准！

Low-boiling phenols in low-temperature coal tar are important chemical raw materials. For the identification and determination of the individual phenol boiling below 210℃ in the low temperature coal tar, the methods of gas chromatography, liquid-liquid chromatography followed by ultra-violet analysis and fractional distillation followed by infrared analysis were evaluated and compared.

随着煤炼油工业的发展，煤焦油中的酚类，特别是低級酚，作为化工原料的利用很重要，我們应用(1)气液色譜法，(2)液液色譜与紫外光譜法結合及(3)精餾与紅外光譜法結合三种不同方法对210°以前的低級酚进行了各种异构体的成分分析，比較分析結果：三种方法对同一样品进行分析时，最大絕对誤差在2％以内，其中以气液色譜法最为快速，液液色譜法次之，精餾-紅外光譜法費时間較多；但后二种方法所得数据較完全。

wax-sweating ; two-stage sweating ; fractional distillation ; low-melting ; dewaxing foots oil ; semi-refined

以石蜡发汗方法生产熔点低于50℃、含油量1.5%以下的低熔点半精炼产品是十分经济的。1原料选择石蜡发汗工艺以酮苯脱蜡后产生的蜡膏为原料进行生产

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。