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第一章半导体的特性

半导体中的电子状态课堂练习

1、单选题：
‏1、以下关于本征半导体的说法，哪个是不正确的​
选项：
A: 本征半导体就是不掺杂的半导体
B: 本征半导体中的载流子是由于本征激发产生的
C: 本征激发产生的载流子多少只和温度有关 
D: 本征激发产生的电子和空穴总是一样多
答案: 【 本征激发产生的载流子多少只和温度有关 】点我阅读全文

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第一章 绪论

单元测验

1、单选题：
​关于信息社会，下列说法不正确的是(   )‌
选项：
A: 计算机的发明和广泛使用是人类社会进入信息社会的唯一标志。
B: 信息社会中所有的工业生产都是自动化的。
C: 在信息社会，信息技术催生大批新兴产业，同时，传统产业也普遍实行技术改造。
D: 信息社会中信息产业高度发展，在产业结构优势的地位日益突出。
E: 在信息社会，信息、知识成为重要的生产力要素。
F: 信息社会是从20世纪中叶开始的，又称后工业社会。
G: 计算机的发明是第三次科技革命的重要标志，是人类文明史上继蒸汽技术革命和电力技术革命之后科技领域里的又一次重大飞跃。
答案: 【 计算机的发明和广泛使用是人类社会进入信息社会的唯一标志。;
信息社会中所有的工业生产都是自动化的。】点我阅读全文

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第一单元

ExercisesforUnitOne&Two

1、单选题：
Part one: There are five sentences in this section. Read and decide whether they are fact or opinion. (10 points, two for each)‍1.China is a developing country.‍​‍
选项：
A: fact
B: opinion
C: none
D: none
答案: 【 fact】点我阅读全文

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第一章 构成概述

1.1构成的概念和历史发展

1、填空题：
1、构成艺术的形式分为_、_、_ 。‎‏‎
答案: 【 平面构成、色彩构成、立体构成】点我阅读全文

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1.宴会设计前准备？

单元测验1

1、单选题：
​宴会销售人员的第一素质要求是（      ）。‏
选项：
A: 具备公关意识   
B: 品质优良
C: 讲究礼貌
D: 掌握餐饮知识
答案: 【 讲究礼貌】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1周体育健康促进概述

单元测验

1、单选题：
‌早在20世纪70年代人们就已发现，高达（     ）的疾病或死亡因素与“行为及不健康的生活方式”有关？‍
选项：
A: 50%‍
B: 50%
C: 30.58%‍
D: 45%
E: 25%
F: 15%
答案: 【 50%‍;
50%】点我阅读全文

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第一章金融法学概述

第一章金融法学概述单元测验题

1、单选题：
‎世界上第一家股份制银行是（  ）​
选项：
A: 英格兰银行
B: 花旗银行
C: 德意志银行
D: 荷兰银行
答案: 【 英格兰银行】点我阅读全文

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第一章 卫生法概述

第一章 单元测试

1、单选题：
‏下列属于平权型法律关系特征的是‌‏‌
选项：
A: 主体双方的法律地位不平等
B: 法律关系主体意思自治
C: 双方的权利义务不对等
D: 双方的权利义务具有法定性
答案: 【 法律关系主体意思自治】点我阅读全文

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第二章工业设计中的心理学

第二章单元测试

1、单选题：
‌以下对自然匹配原则理解正确的是：‌
选项：
A: 设计产品时，需考虑如何利用物理环境类比和文化标准理念，设计出让用户一看就明白如何使用该产品
B: 设计产品时，需要遵循材料的自然属性
C: 设计产品时，要了解目标用户需求与产品的匹配度
D: 设计产品时，不能打破该产品的传统形式
答案: 【 设计产品时，需考虑如何利用物理环境类比和文化标准理念，设计出让用户一看就明白如何使用该产品】点我阅读全文

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