液—液萃取是分离液体混合物的单元操作,它利用液体混合物中各组分在溶剂中溶解度的差异而

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问题:

液—液萃取是分离液体混合物的单元操作,它利用液体混合物中各组分在溶剂中溶解度的差异而达到分离的目的。由于所选用的溶剂与被分离的混合物形成互不相容或部分互溶的两相,其中一相以萃取剂为主(),另一相以被分离组分中某组分为主(),通过两相的分离达到混合物分离的目的。

考点:丁二烯装置操作工丁二烯装置操作工题库
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Part B: Vocabulary 9%

A.claim

B.second

C.opposite

D.count E. bestF. negative       G. failures         H. defined          I. mark          J. reliable  

We might be surprised at the progress made in every field of study, but the methods of testing a person’s knowledge and ability remain as primitive as ever they were. It is really extraordinary that after all years, educationists have still failed to devise something more 41 than examinations. For all the 42 that examinations test what you know, it is common knowledge that they more often do the exact 43. They may be a good means of testing memory, or the knack of working rapidly under extreme pressure, but they can tell you nothing about a person’s true ability.

As anxiety-makers, examinations are 44 to none. That is because so much depends on them. They are the 45 of success or failure in our society. Your whole future may be decided in one fateful day. It doesn’t matter that you weren’t feeling very well, or that your mother died. Little things like that don’t 46: the exam goes on. No one can bring out the 47 in him when he is in terror, or after a sleepless night, yet this is precisely what the examination system expects him to do. The moment a child begins school, he enters a world of fierce competition where success and failure are clearly 48 and measured. Can we wonder at the increasing number of “dropouts”: young people who are written off as 49 before they have started a career? Can we be surprised at the suicide rate among students?

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《生活垃圾填埋污染控制标准》(GB 16889—1997)适用于( )。

A.生活垃圾填埋处置场所
B.工业固体废物填埋处置场所
C.危险废物填埋处置场所
D.放射性固体废物填埋处置场所

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男性,21岁。近半年来反复心悸、胸痛、劳力性呼吸困难。时有头晕或短暂神志丧失。体检发现:心脏轻度增大,心尖部有2级收缩期杂音和第四心音,胸骨左缘第3~4肋间闻及较粗糙的喷射性收缩期杂音。

最可能的诊断是()。

A.冠心病心绞痛

B.二尖瓣关闭不全

C.主动脉瓣狭窄

D.肥厚型梗阻性心肌病

E.病毒性心肌炎

题型:填空题

下列各项中,不属于企业会计基本准则的内容是( )。

A.财务会计报告目标

B.会计报表具体格式

C.会计基本假设和会计基础

D.会计信息质量要求

题型:填空题

更换CD10电磁操动机构的分闸线圈时,应测量分闸线圈的()。

A.直流电阻

B.直流耐压

C.绝缘电阻

D.绝缘,直流电阻,极性

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