【单选题】
汽轮机启动进入___时，零部件的热应力值最大。
A. 极热态；
B. 热态；
C. 稳态；
D. 准稳态。
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答案
D
解析
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【单选题】
当汽轮发电机组转轴发生动静摩擦时，___。
A. 振动的相位角是不变的；
B. 振动的相位角是变化的；
C. 振动的相位角有时变有时不变；
D. 振动的相位角起始变化缓慢，以后加剧。
【单选题】
当转轴发生自激振荡时，___。
A. 转轴的转动中心是不变的；
B. 转轴的转动中心围绕几何中心发生涡动；
C. 转轴的转动中心围绕汽缸轴心线发生涡动；
D. 转轴的转动中心围绕转子质心发生涡动。
【单选题】
给水泵在运行中的振幅不允许超过0.05mm，是为了___。
A. 防止振动过大，引起给水压力降低；
B. 防止振动过大，引起基础松动；
C. 防止轴承外壳遭受破坏；
D. 防止泵轴弯曲或轴承油膜破坏造成轴瓦烧毁。
【单选题】
汽轮机发生水冲击时，导致轴向推力急剧增大的原因是___。
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【单选题】
国产300、600MW汽轮机参加负荷调节时，机组的热耗表现为___。
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B. 三阀全开复合变压运行比纯变压运行高；
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作真空系统严密性试验时，如果凝汽器真空下降过快或凝汽器真空值低于___MPa，应立即开启抽气器空气泵，停止试验。
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【多选题】
运行中通过监视调节级压力的变化可以判断___
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B. 通流部分是否存在结垢、损坏及堵塞
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【多选题】
汽轮机运行中发生振动，可能的原因有___
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【多选题】
运行中给水温度下降的原因有___
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(1)Whieh of the following descriptions about the characteristics of physiology is wrong？___
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【单选题】
(2) Which of the following are specialized in producing force and movement?___
A. muscle cells
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【单选题】
(3)The fluid environment surrounding each cell is called the___
A. intracellular fluid
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【单选题】
(4) Which of the following is not the fundamental characteristic of living organisms?___
A. metabolism
B. adaption
C. reproduction
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【单选题】
(5)Whicl of the following is a physiological process with negative feedback?___
A. blood coagulation
B. process of passing urine
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【单选题】
(6)Which of the following is not the characteristic of regulation by hormone?___
A. diffusenin nature
B. longer in duration
C. accurate in action
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【单选题】
7)Which of the following is not the characteristic of cells?___
A. They are bound by the plasma membrane
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C. They possess a nucleus which contains genetic information in the form of deoxyribonucleicacid(DNA).
D. Living cells can not transform materials.
【单选题】
8)The breakdown of large molecules to smaller ones is called___
A. respiration
B. anabolism
C. catabolism
D. absorption
【单选题】
9) Which of the following descriptions about the characteristics of nervous regulation is wrong?___
A. It responds fast
B. It acts exactly
C. It responds slowly.D.
D. uration is short
【单选题】
10)Which of the following descriptions about the control of body function is wrong?___
A. Homeostasis is kept by feedback control.
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C. Positive feedback is not useful.
D. Feed-forward makes human body foresee and adapt itself to the environment promptly.
【单选题】
(1)Which of the following parts of knowledge of drugs should be included in pharmacology?___
A. The effects of drugs on man
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【单选题】
(2)Which of the following is what a clinician is primarily interested in according to the text?___
A. Drugs which can be reasonably limited to those aspects that provide the basis for their rational clinical use
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D. rugs which are useful in the prevention, diagnosis and treatment of human disease, or in the prevention of pregnancy.
【单选题】
(3)Why was the physician not interested in pharmacognosy?___
A. He didn't have to select the proper plants for his prescription
B. He had a broad botanical knowledge
C. Fewer drugs were obtained from natural sources
D. Natural drugs had little difference with synthetic ones
【单选题】
(4)Which of the following is the best way of studying pharmacology for medical students and practitioners?___
A. to have a broad botanical knowledge
B. to select a plant and its preparation
C. to have the ability to purify natural plants
D. to have curiosity that stimulates them to learn about sources of drugs
【单选题】
(5)What are the tasks related to medicines almost complete!y delegated to the pharmacists now?___
A. the physical and chemical properties of medicines
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C. dosage forms of medicines available
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【单选题】
(6) What is a main unique aspect of pharmacodynamics?___
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