【判断题】
10kV 三相供电系统一般采用中性点不接地或高电阻接地方式。
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人体触电时 , 大脑易损期最为敏感 , 也最容易受到伤害而发生昏迷 , 而导致血液循环中止死亡。
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变压器型号中横短线后面的数字表示变压器的额定容量 , 其单位是 kVA。
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工作许可制度是指在电气设备上进行任何电气作业,都必须填写工作票,并根据工作票布置安全措施和办理开工,终结等手续
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干式变压器所在环境的相对湿度应不大于 50%
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变压器利用电磁感应原理,把交流输入电压升高降低为不同频率的交流输出电压
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高压验电器每六个月要进行一次预防性实验
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在中性点不接地系统中发生单相间歇性电弧接地时,可能会产生电弧接地过电压
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合金绞线( LHJ)常用于 110kV 及以上的输电线路上
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弹簧操作机构是利用弹簧瞬间释放的能量完成断路器的合闸的
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在有可燃气体的环境中,为了防止静电火花引燃爆炸,应采用天然橡胶或者高阻抗的人造橡胶作为地板装修材料
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气体继电器是针对变压器内部故障安装的保护装置
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在变压器的保护中,过电流保护是位于后备保护
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电压互感器的熔丝熔断时,备用电源的自动装置不应动作
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输出电路与输入电路共用了发射极,简称共发射极电路
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工作票是准许在电气设备上工作的书面命令,是执行保证安全技术措施的书面依据,一般有三种格式
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绝缘鞋可作为防护跨步电压的基本安全用具
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合金绞线( THJ)常用于 110kV 及以上的输电线路上
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巡视并联使用的电缆有无因过负荷分配不均匀而导致某根电缆过热是电缆线路日常巡视检查的内容之一
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钳表铁芯内的剩磁只影响大电流测量,而对小电流测量无影响
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用数字万用表测量直流电压时,极性接反会损坏数字万用表
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操作开关时,由于开关的灭弧能力不够强,触头在断开瞬间有可能发生电弧燃烧引起操作过电压
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供电系统中三相电压对称度一般不应超过额定电压的 5%
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推荐试题
【单选题】
In the eyes of the author, a successful engineering student is expected ______________.___
A. to be imaginative with a value system to guide him
B. to be a technical genius with a wide vision
C. to have an excellent academic record
D. to be wise and mature
【单选题】
The author's experience shows that he was ________.___
A. creative
B. ambitious
C. irrational
D. unrealistic
【单选题】
The underlined word "they" in "... together they threaten to confuse." (Para.5) refers to ____________.___
A. practicality and rationality
B. engineering and the liberal arts
C. reality and noble ideals
D. flexibility and a value system
【单选题】
It can be learned from the passage that the Ouchidas' house __________.___
A. failed to meet energy conservation standards
B. was designed and constructed in a scientific way
C. is well worth the money spent on its construction
D. is almost faultless from the point of energy conservation
【单选题】
What made the Ouchidas' new house a horrible dream?___
A. Lack of fresh air.
B. Gas leakage in the kitchen.
C. The newly painted walls.
D. Poor quality of building materials.
【单选题】
The underlined word "accentuate" (Para. 3) most probably means "________".___
A. worsen
B. accelerate
C. relieve
D. improve
【单选题】
Why were cracks in old houses not a big concern?___
A. Because environmental protection was given top priority.
B. Because indoor cleanness was not emphasized.
C. Because they were technically unavoidable.
D. Because energy used to be inexpensive.
【单选题】
This passage is most probably taken from an article entitled "_________".___
A. Energy Conservation
B. Air Pollution Indoors
C. House Building Crisis
D. Traps in Building Construction
【单选题】
We need to plan ahead in order to ___________.___
A. keep a record of all the events
B. better organize our activities
C. store everything in our head
D. pile up little tasks neatly
【单选题】
Strategic times are best for us to ___________.___
A. save energy
B. check e-mails
C. study efficiently
D. organize activities
【单选题】
Which of the following could be used as a motivation to do our assignments?___
A. Remembering our urgent tasks.
B. Any activities we're eager to do.
C. Taking a break in the afternoon.
D. The promise to study efficiently.
【单选题】
What can help us to keep refreshed throughout the day?___
A. Doing some physical exercise.
B. Taking a short nap in the afternoon.
C. Rushing through some assignments.
D. Playing a game of chess with a friend.
【单选题】
Which of the following could be the best title for this article?___
A. Study Habits and Time Management
B. Business Management and Leadership
C. University Education and Campus Life
D. Life Goals and Academic Development
【单选题】
It is implied in the text that it is hard to ________.___
A. carry life learning though
B. tell the nature of life learning
C. learn without going to school
D. find a specially trained teacher
【单选题】
According to the author, the schooling framework often ________.___
A. produces slow students with poor memories
B. ignores some parts of the official curriculum
C. fails to provide enough knowledge about life
D. gives little care to the quality of teaching materials
【单选题】
Life learners recognize that learning will not be difficult if they are _________.___
A. clear about why to learn
B. careful to make a time table
C. able to respect other people
D. cautious about any mistakes
【单选题】
According to the author, life learning ________.___
A. could prevent one from running risks
B. could be a road full of trials and errors
C. makes a kid independent of his parents
D. teaches a kid how to avoid being scorned
【单选题】
Through life learning, children ________.___
A. will grow without the assistance from parents
B. will learn to communicate with the real world
C. will be driven to learn necessary life knowledge
D. will be isolated from the negative side of society
【单选题】
A good title for this passage is __________.___
A. Sleep
B. Good Health
C. Dreams
D. Work and Rest
【单选题】
The word drowsy in the last paragraph means __________.___
A. sick
B. stand up
C. asleep
D. a little sleepy
【单选题】
This passage suggests that not getting enough sleep might make you ___________.___
A. dream more often
B. have poor health
C. nervous
D. breathe quickly
【单选题】
During REM, ___________ .___
A. your eyes move quickly
B. you dream
C. you are restless
D. both A and B
【单选题】
The average number of hours of sleep that an adult needs is __________.___
A. approximately six hours
B. around ten hours
C. about eight hours
D. not stated here
【填空题】
4、Sjogren syndrome___
【填空题】
2、唇腭裂治疗的新概念是___,即___。常包括以下医师:___及___、___、___。
【填空题】
3、颌面部外伤后易出现两类窒息:阻塞性窒息和___、阻塞性窒息常见于三种情况:___、___、___。