PVA高压电动机采用()保护装置作过负荷的保护,采用电流速断保护装置作相同短路保护。

题型:单项选择题

问题:

PVA高压电动机采用()保护装置作过负荷的保护,采用电流速断保护装置作相同短路保护。

A、电流速断

B、定时限过电流

C、反时限过电流

D、热过载

考点:初级维修电工初级维修电工题库
题型:单项选择题

从所给的四个选项中,选择最符合左侧图形规律的一项:()。

A.A

B.B

C.C

D.D

题型:单项选择题

桂枝功善于( )

A.回阳救逆
B.补火助阳
C.温胃止呕
D.发汗平喘
E.发表解肌

题型:单项选择题

科研不端是一个老问题,也是一个全球性的问题。近几年来,韩国首尔大学教授黄禹锡干细胞造假、日本东京大学教授多比良基因研究造假等一系列造假事件纷纷。当前。我国正处于剧烈的经济社会转变之中,科研不端之势也呈上升之势。中国科协进行的一项调查表明,近三成科技工作者认为其周围存在严重的学术不端行为,其中尤以抄袭和剽窃他人成果、伪造数据或弄虚作假、技术成果交易中夸大技术价值或隐瞒技术风险三种行为最为普遍。像“汉芯一号”这样的造假事件,已经不仅仅是学术不端行为了。

高校教师从事科学研究的职业品质是()。

A.求知创新

B.治学严谨

C.献身教育

D.甘于奉献

题型:单项选择题

社会越轨是指违反社会规范的行为,有积极性、消极性、中性三种不同类型。其中积极性社会越轨是对社会发展起积极进步作用的越轨行为。这种社会越轨是打破因循守旧、推动社会发展的动力之一。 根据以上定义,下列属于积极性社会越轨行为的是( )。

A.少年离家出走

B.未婚同居

C.年满14岁即拒绝父母抚养

D.美术教学中使用裸体模特

题型:单项选择题

The first two stages in the development of civilized man were probably the invention of primitive weapons and the discovery of fire, although nobody knows exactly when he acquired the use of the latter.
41) ______ Animals have a few cries that serve as signals, but even the highest apes have not been found able to pronounce words, even with the most intensive professional instruction. The superior brain of man is apparently a necessity for the mastering of speech. When man became sufficiently intelligent, we must suppose that he gradually increased the number of cries for different purposes. It was a great day when he discovered that speech could be used for narrative. There are those who think that in this respect picture language preceded oral language. A man could draw a picture on the wall of his cave to show in which direction he had gone, or what prey he hoped to catch. 42) ______
Two important stages came not so long before the dawn of written history. The first was the domestication of animals; the second was agriculture. Agriculture made possible an immense increase in the number of the human species in the regions where it could be successfully practiced. 43) ______
44) ______
These inventions and discoveries--fire, speech, weapons domestic animals, agriculture, and writing--made the existence of civilized communities possible. From about 3000 B. C. until the beginning of the Industrial Revolution less than two hundred years ago there was no technical advance comparable to these. During this long period man had time to become accustomed to his technique, and to develop the beliefs and political organizations appropriate to it. There was, of course, an immense extension in the area of civilized life. At first it had been confined to the Nile, the Euphrates, the Tigris, and the Indus, but at the end of the period in question it covered much the greatest part of the inhabitable globe. I do not mean to suggest that there was no technical progress during the time. 45) ______ (512 words)
Notes: ape 猿。pastoral nomad 田园式的游牧部落的人。the Euphrates 幼发拉底河。the Tigris底格里斯河。the Indus 印度河。in question 所谈的(在名词后作后置定语)。
[A] Probably picture language and. oral language developed side by side. I am inclined to think that language has been the most important single factor in the development of man.
[B] Another fundamental technical advance was writing, which, like spoken language, developed out of pictures, but as soon as it had reached a certain stage, it was possible to keep records and transmit information to people who were not present when the information was given.
[C] With the development of civilization, primitive people who lived in caves at that time badly needed a language, which would help them to communicate with one another.
[D] The origin of language is also obscure. No doubt it began very gradually.
[E] In fact, there was progress--there were even two inventions of very great importance, namely, gunpowder and the mariner’s compass--but neither of these can be compared in their revolutionary power to such things as speech and writing and agriculture.
[F] These were, at first, only those in which nature fertilized the soil after each harvest. Agriculture met with violent resistance from the pastoral nomads, but the agricultural way of life prevailed in the end because of the physical comforts it provided.
[G] But industry was a step in human progress to which subsequently there was nothing comparable until our own machine age.

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