mooc标签存档

第一章 文献检索概论

第一章文献检索概论单元测验

1、单选题：
‌文献的检索中以主题词进行检索的途径是‍
选项：
A: 主题途径
B: 著者途径
C: 号码途径
D: 分类途径
答案: 【 主题途径】点我阅读全文

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第1周 认识大漆

漆艺概述

1、单选题：
​漆画在何时发展成绘画？​
选项：
A: 20世纪30年代
B: 20世纪50-60年代
C: 20世纪60-70年代
D: 20世纪90年代
答案: 【 20世纪50-60年代】点我阅读全文

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1.巴赫复调钢琴作品的演奏

巴赫复调钢琴作品的演奏单元测验

1、填空题：
​巴赫被称为_______‍
答案: 【 西方音乐之父】点我阅读全文

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第六章 含卤有机化合物

6-10 卤代烃与金属的反应

1、单选题：
​合成格氏试剂一般在下列哪一溶剂中反应? ‍
选项：
A: 醇
B: 醚
C: 酯
D: 石油醚
答案: 【 醚】点我阅读全文

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第1章 城市轨道交通概述

交通方式与城市发展

1、判断题：
地铁和轻轨同属于城市轨道交通的一部分，是具有快速、安全、能耗低、污染小的绿色交通方式。‏‌‏
选项：
A: 正确
B: 错误
答案: 【 正确】点我阅读全文

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第一章 口腔颌面部发育

单元测验

1、单选题：
‏面部的发育从胚胎哪一周开始出现面突的分化​
选项：
A: 1
B: 2
C: 3
D: 4
答案: 【 3】点我阅读全文

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Lesson 2

Scanning

1、单选题：
‎Read the passage "The Discovery of X-rays" quickly and choose the paragraph(s) which contain(s) the answer(s). You may choose more than one answer for question 3. ​‎​The Discovery of X-rays​‎ ​Par. 1 Except for a brief description of the Compton effect, and a few other remarks, we have postponed the discussion of X-rays until the present chapter because it is particularly convenient to treat X-ray spectra after treating optical spectra. Although this ordering may have given the reader a distorted impression of the historical importance of X-rays, this impression will be corrected shortly as we describe the crucial role played by X-rays in the development of modern physics.​Par. 2 X-rays were discovered in 1895 by Roentgen while studying the phenomena of gaseous discharge. Using a cathode ray tube with a high voltage of several tens of kilovolts, he noticed that salts of barium would fluoresce when brought near the tube, although nothing visible was emitted by the tube. This effect persisted when the tube was wrapped with a layer of black cardboard. Roentgen soon established that the agency responsible for the fluorescence originated at the point at which the stream of energetic electrons struck the glass wall of the tube. Because of its unknown nature, he gave this agency the name X-rays. He found that X-rays could manifest themselves by darkening wrapped photographic plates, discharging charged electroscopes, as well as by causing fluorescence in a number of different substances. He also found that X-rays can penetrate considerable thicknesses of materials of low atomic number, whereas substances of high atomic number are relatively opaque. Roentgen took the first steps in identifying the nature of X-rays by using a system of slits to show that (1) they travel in straight lines, and that (2) they are uncharged, because they are not deflected by electric or magnetic fields.​Par. 3 The discovery of X-rays aroused the interest of all physicists, and many joined in the investigation of their properties. In 1899 Haga and Wind performed a single slit diffraction experiment with X-rays which showed that (3) X-rays are a wave motion phenomenon, and, from the size of the diffraction pattern, their wavelength could be estimated to be 10-8 cm. In 1906 Barkla proved that (4) the waves are transverse by showing that they can be polarized by scattering from many materials.​Par. 4 There is, of course, no longer anything unknown about the nature of X-rays. They are electromagnetic radiation of exactly the same nature as visible light, except that their wavelength is several orders of magnitude shorter. This conclusion follows from comparing properties 1 through 4 with the similar properties of visible light, but it was actually postulated by Thomson several years before all these properties were known. Thomson argued that X-rays are electromagnetic radiation because such radiation would be expected to be emitted from the point at which the electrons strike the wall of a cathode ray tube. At this point, the electrons suffer very violent accelerations in coming to a stop and, according to classical electromagnetic theory, all accelerated charged particles emit electromagnetic radiations. We shall see later that this explanation of the production of X-rays is at least partially correct.​Par. 5 In common with other electromagnetic radiations, X-rays exhibit particle-like aspects as well as wave-like aspects. The reader will recall that the Compton effect, which is one of the most convincing demonstrations of the existence of quanta, was originally observed with electromagnetic radiation in the X-ray region of wavelengths.​‎​‎When were X-rays discovered?​
选项：
A: Par. 1
B: Par. 2
C: Par. 3
D: Par. 4
E: Par. 5
答案: 【 Par. 2】点我阅读全文

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项目三 丰田U341E型自动变速器的认识与拆装

项目三-单元测验

1、单选题：
‏关于U341E型自动变速器，下列说法错误的是         。‌‌‏‌
选项：
A: 有2个行星齿轮排
B: 有四个前进挡
C: 有6个换挡执行元件
D: 为电控自动变速器
答案: 【 有6个换挡执行元件】点我阅读全文

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第一章 会计法律制度

第一单元测试

1、单选题：
‌2018年4月，ABC公司内部机构调整：会计小张调离会计工作岗位，离岗前与接替者小江在财务科长的监交下办理了会计工作交接手续。下列说法正确的为（ ）。‍
选项：
A: 小张与小江办理会计工作交接时还应该有公司人事部门派人参加监交
B: 小张与小江的会计工作交接不符合规定
C: 小张与小江的会计工作交接符合规定
D: 小张与小江办理会计工作交接时还应该有公司经理在场监交
答案: 【 小张与小江的会计工作交接符合规定】点我阅读全文

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