【单选题】
在开关电器中,气体吹动电弧的方法为横吹时,气体吹动方向与电弧轴线相___。
A. 平行
B. 垂直
C. 倾斜30o角度
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答案
B
解析
暂无解析
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线路验电应逐相进行。同杆架设的多层电力线路验电时,先验低压后验高压、___。
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隔离开关采用操动机构进行操作,便于在隔离开关与___安装防误操作闭锁机构。
A. 母线之间
B. 断路器之间
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在一类负荷的供电要求中,允许中断供电时间在___小时以上的供电系统,可选用快速自启动的发电机组。
A. 12
B. 13
C. 14
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断路器的额定开断电流表明了断路器的___。
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作用于人体的电压升高,人体电阻还会___,致使电流更大,对人体的伤害更严重。
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当变压器过负载时,一般会发出___。
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当验明设备确已无电压后,应立即将检修设备三相短路并___。
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操作票填写中,合上或拉开的隔离开关,刀开关统称为___。
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规定在磁体外部,磁力线的方向是___。
A. 由S极到达N极
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如果忽略变压器的内损耗,可认为变压器二次输出功率___变压器一次输入功率。
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停电检修线路,应将所有___及联络断路器和隔离开关都拉开。
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隔离开关的主要作用之一是___。
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为提高功率因数;运行中可在工厂变配电所的母线上或用电设备附近装设___,用其来补偿电感性负载过大的感性电流,减小无功损耗,提高末端用电电压。
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对变配电所内的电气设备、备用设备及继电保护自动装置等需定期进行___和轮换。
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【单选题】
下列关于保护变压器的角型间隙安装位置描述正确的是___。
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【单选题】
___的作用是警告工作人员不得接近设备的带电部分,提醒工作人员在工作地点采取安全措施,以及禁止向某设备合闸送电等。
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C. 中性线(零线)N与保护线P
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F. 是部分合用的
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正常情况直线杆塔一般不承受___。
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梯子分为人字梯和___。
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作为电气工作者,员工必须熟知本工种的___和施工现场的安全生产制度,不违章作业。
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小电流真空灭弧室一般采用___触头。
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电力线路过电流保护动作时间的整定采取阶梯原则,时限阶段差Δt一般设置为___。
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电流互感器的变流比为一次绕组的___与二次绕组额定电流之比。
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断路器的关合电流是指保证断路器可靠关合而又不会发生触头熔焊或其它损伤时,断路器允许通过的___。
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断路器的额定电流是指在规定环境温度下,断路器长期允许通过的___。
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电路闭合时,电源的端电压___电源电动势减去电源的内阻压降。
A. 大于
B. 小于
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A. 1-2
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推荐试题
【单选题】
(9)Which of the following is true when drugs are selected?___
A. It has to be based in part on legal reasons.
B. It has to be based in part on ethical reasons.
C. It has to be based in part on the pharmacological evaluation in man
D. It has to be based in part on the pharmacological evaluation in animals
【单选题】
(10)Why are chemotherapeutic agents useful in therapy?___
A. They stimulate or depress biochemical or physiological function in man in a sufficiently reproducible manner to provide relief of symptoms or, ideally, to alter favorably the course of disease
B. They can produce desired effects with only tolerable undesired effects
C. They have only minimal effects on man but can destroy or eliminate parasites
D. The selectivity of their effects is one of their most important characteristics
【单选题】
1)H. Mario Geysen initially used parallel synthesis as a quick way to identify which small_____ of any given large protein bound to an antibody.___
A. division
B. pieces
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D. fragment
【单选题】
2)Chemists often start a combinatorial synthesis by attaching the first set of building blocks_____ to microscopic beads made of polystyrene.___
A. solid
B. inert
C. soft
D. active
【单选题】
3)The chemical reactions required to link compounds to the beads and later to detach them____ to the synthesis proces.___
A. induce complications
B. make easy
C. introduce complications
D. introduce easy
【单选题】
4)In a parallel synthesis, all the products are_____ separately in their own reaction vessels.___
A. combined
B. assembled
C. joined
D. assorted
【单选题】
(5)In many laboratories today, robots assist with the routine work of parallel synthesis, such as small___ amounts of reactive molecules into the appropriate wells.___
A. sending
B. transporting
C. delivering
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【单选题】
(6)Scientists can pull out from the mixture the beads that bear biologically active molecules and then,using sensitive detection techniques,___ the molecular makeup of the compound attached.___
A. determine
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C. find
D. search
【单选题】
(7)Most pharmaceutical companies today continue to___ parallel synthesis. Which of the following is not appropriate to be filled in the blank?___
A. count in
B. count on
C. depend on
D. rely on
【单选题】
(8)Once they identify a promising substance, they___ make many one-at-a-time modifications to the structure.___
A. laboriously
B. hardly
C. easy
D. effectively
【单选题】
(9)Often these procedures yield a compound having acceptable___ and safety.___
A. strength
B. effect
C. potency
D. effort
【单选题】
10)In many laboratories today, robots___ the routine work of parallel synthesis.___
A. help
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C. assist in
D. assist to
【单选题】
(1)Pharmaceutics is an interdisciplinary subject involving___
A. formulation, manufacturing, physical pharmacy, and biopharmaceutics
B. manufacturing
C. physical pharmacy
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【单选题】
(2)Formulation is about the design, development and evaluation of dosage forms,___
A. discovery of novel drugs
B. analytical methods
C. drug delivery systems and manufacturing process
D. dosing regimen
【单选题】
(3)Biopharmaceutics mainly studies the in vivo process of drugs and metabolites in humans, animals and tissue culture, which specifically involves___
A. absorption and distribution
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【单选题】
(4)Regarding the definition of bioavailability(BA), BA is related to___
A. total plasma drug concentration only
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【单选题】
(5)Plasma drug concentration is affected by following factors such as___
A. rate of absorption
B. rate and extent of distribution
C. rate ofeli Imination
D. all ofabove
【单选题】
6)Which of the following routes of administration will involve the absorption of drugs?___
A. i.v.injection
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D. None of above
【单选题】
(7)Which of the following factors may influence the time course of a drug in the plasma and hence at its site of action?___
A. Food
B. Disease state
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【单选题】
(8)Please identify the potential biological barriers for an orally administered tablet to be absorbed into the systemic circulation___
A. Sk d dermis
B. Gastrointestinal epithelium
C. Oral mucosal membrane
D. All of above
【单选题】
(9) Given the same administration dose, which of the following will likely result in varying bioavailabilities for the same drug administered to the same person? ___
A. tablets (p.o. )vs. solutions(p0.)
B. solutions for injection(i v )vs oral solutions(p0.)
C. coated tablets (p.0. )vs hard gelatin capsules(p0.)
D. All ofabove
【单选题】
(10)Which of the following statements is true?___
A. Bioavailability is only related to the administered dose and the total drug concentration in the blood circulation.
B. Plasma protein binding does not affect the bioavailability of a specific drug.
C. A given drug in different dosage forms may show differences in bioavailability if given by the same route.
D. Biopharmaceutical studies do not involve animal experiment.
【判断题】
Much of our present physiological knowledge has been found from the experiments and studies on human beings.
A. 对
B. 错
【判断题】
Living cells break down glucose and fats to provide energy for other activities, which is called.
A. 对
B. 错
【判断题】
The right atriapumps deoxygenated blood to the lungs where it absorbs oxygen from the air.
A. 对
B. 错
【判断题】
The nervous system uses electrical signals to transmit information very rapidly to specific cells.
A. 对
B. 错
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With the level of sodium increasing extracelular fruid. the cardiac muscle cells become too excitable and may contract.
A. 对
B. 错
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A negative feedback loop is a control system that acts to maintain the level of some variables within a given range following a disturbance
A. 对
B. 错
【判断题】
(1)Pharmacodynamics, which is concerned with the study of the biochemical and physiological effects of drugs and their mechanisms of action, Is an experimental medical science.
A. 对
B. 错
【判断题】
2)It's unreasonable for a physician to be interested mainly in the effects of drugs on human beings, for the pharmacological evaluation of drugs in them may be limited due to technical, legal, and ethical reasons.
A. 对
B. 错
【判断题】
(3) As the effects of drugs are often characterized by significant interspecies variation and may be further modified by disease, clinical pharmacology has never been efibrasized.
A. 对
B. 错
【判断题】
The physician is not interested in drugs that are useful in the prevention,diagnosis,and treatment of human disease, but in chemical agents that are commonly responsible for household and industrial poisoning as well as environmental pollution.
A. 对
B. 错
【判断题】
(5)A drug is said to be useful in therapy if it has the ability to produce its desired effects with only tolerable undesired effects.
A. 对
B. 错
【判断题】
(6)Toxicology deals not only with drugs used in therapy but also with many other chemicals that may be responsible for household, environmental, or industrial intoxication.
A. 对
B. 错
【判断题】
1)With the more efficient screening tests and burgeoning knowledge about how a molecules biological activities are likely to be changed, the traditional approach of discovering new drugs has been improved.
A. 对
B. 错
【判断题】
2)With the parallel synthesis used to identify which small segment of any given large protein would bind to an antibody, Mario Geysen generated a variety of short protein fragments by combining multiple amino acids in different permutations.
A. 对
B. 错
【判断题】
)A parallel synthesis and a split-and-mix synthesis are different in that in a split-and-mix synthesis, all the products are assembled separately n their respective reaction vessels.
A. 对
B. 错
【判断题】
4) In many laboratories, robots are used in the routine work of parallel synthesis to deliver small amounts of reactive molecules into appropriate wells, thus making the process more accurate and less tedious.
A. 对
B. 错
【判断题】
5) In a parallel synthesis, each compound remains in its own container; while in a split-and-min synthesis, the related ce mpounds are mixed up in the same reaction vessel.
A. 对
B. 错
【判断题】
6)In order to solve the difficulties of identifying the compounds made in a parallel synthesis scientists pull out from the mixture the beads that bear biologically active molecules and determine the molecular makeup o d attached.
A. 对
B. 错