搜题请搜索小程序“爱下问搜题”
问题 填空题

朗伯-比耳定律可表示为A=εbc，其中b代表______，c代表______，ε称为______。

答案

参考答案：比色皿厚度(或者液层厚度)；物质的量浓度；摩尔吸光系数。

单项选择题

Visitors to this country are normally admitted for six months, but foreign students can usually stay for one year. They must (52) an educational institution, and they are required to study for a (53) of fifteen hours a week on a daytime course. Prospective students have to show that they can afford their studies, and that they have sufficient (54) resources to support themselves (55) in this country.

In order to work here the foreigner needs a work permit, (56) must be applied for by his prospective employer. The problem here is that the Department of Employment has the right to grant or (57) these permits, and there is little that can be done (58) it; it would be extremely unwise for a foreign visitor to work (59) a permit, since anyone doing so is liable to immediate deportation (驱逐出境). There are some people from the European countries, who are often given (60) residence permits of up to five years. Some other people, such as doctors, foreign journalists, authors and others can work without permits, and foreign students are normally allowed to (61) part-time jobs while they are studying here.

57().

A.receive 

B.refuse 

C.oppose 

D.accept
查看答案
多项选择题

适应电网设备状态检修工作需要，改变以（）为核心的技术监督管理模式和工作内容。

A.预防性试验

B.故障检修

C.定期计划检修

D.临时性检修
查看答案