慕课标签存档

第一讲  走进思维导图

1.1.4测测你对思维导图的认识

1、判断题：
‌思维导图可以将人们的思维过程和思考结果可视化。‎
选项：
A: 正确
B: 错误
答案: 【 正确】点我阅读全文

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1- 初识模拟电子技术从二极管开始

1 测试进阶

1、单选题：
‎PN结加正向电压时，空间电荷区将‎
选项：
A: 变窄
B: 变宽
C: 不变
D: 不确定
答案: 【 变窄】点我阅读全文

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第二章货币法

第二章货币法测验题

1、单选题：
‍中国的法定货币是（  ）‎
选项：
A: 美元
B: 人民币
C: 欧元
D: 港币
答案: 【 人民币】点我阅读全文

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第一单元 心理健康与我

单元测验

1、判断题：
​一个人，只要身体没病就是健康。​
选项：
A: 正确
B: 错误
答案: 【 错误】点我阅读全文

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第二周生物制药工艺技术基础

第一、二单元测验

1、单选题：
​以下能用重组DNA技术生产的药物为（）‍
选项：
A: 维生素 
B: 人生长素   
C: 肝素     
D: 链霉素
答案: 【 人生长素   】点我阅读全文

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第1章丝绸历史与文化

随堂测验

1、单选题：
《雍正像耕织图册》分为（ ）和（ ）两部分。‌‏‌
选项：
A: 织图、练图
B: 织图、染图
C: 耕图、染图
D: 耕图、织图 
答案: 【 耕图、织图  】点我阅读全文

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Lesson2

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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第一章脑卒中(俗称中风)防治入门知识

第一单元测试

1、单选题：
‌脑卒中是哪个疾病的学名？ ‌
选项：
A: 脑梗死
B: 脑出血
C: 脑中风
D: 脑栓塞
答案: 【 脑中风】点我阅读全文

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第九讲

第一次单元测验

1、单选题：
‍下列哪项财务指标侧重衡量企业的偿债能力状况？‎‍‎‍‎
选项：
A: 总资产周转率
B: 流动比率
C: 净利润
D: 流动资产周转率
答案: 【 流动比率】点我阅读全文

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第1章 绪论

1.4 行政管理学的研究对象与研究方法

1、单选题：
‎德国学者冯· 史坦因（Lorenzvon Stein）。他于1865年撰写了《行政学》一书，但他当时主要是在（）的意义上使用“行政学”一词的‎
选项：
A: 民法
B: 行政法
C: 经济法
D: 程序法
答案: 【 行政法】点我阅读全文

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