【单选题】
电流表的读数是4A，则电路中电流表的读数是 ___
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【单选题】
在R、L、C串联电路中，已知＝3Ω，＝5Ω，＝8Ω，则电路的性质为 ___。
A. 感性
B. 容性
C. 阻性
D. 不能确定
【单选题】
工业生产中大量的设备均为感性负载，功率因数往往很低，常采取___的方法来提高电网的功率因数。
A. 并联电容
B. 串联电容
C. 串联电感
D. 并联电感
【单选题】
交流电压表及电流表指示的数值是___
A. 平均值
B. 有效值
C. 最大值
D. 瞬时值
【单选题】
RLC串联电路发生谐振，，R=10Ω，Ω，则谐振时的感抗为___
A. 10Ω
B. 40Ω
C. 20Ω
D. 30Ω
【单选题】
RL从电路获得最大功率，此时RL=___。
【单选题】
使用电解电容时___。
A. 负极接高电位，正极接低电位
B. 正极接高电位，负极接低电位
C. 正极接高电位，负极也可以接高电位
D. 不分正负极
【单选题】
开关接1时，电压表的读数为___。
A. 0V
B. 0.2V
C. 1.96V
D. 2V
【单选题】
开关接2时，电流表的电流为___。
A. 0A
B. 10A
C. 0.2A
D. 约等于0.2A
【单选题】
开关接1时，电流表中流过的短路电流为___。
A. 0A
B. 0.2A
C. 10A
D. 约等于0.2A
【单选题】
正弦交流电常用的表达方法有___。
A. 解析式表示法
B. 波形图表示法
C. 相量表示法
D. 以上都是
【单选题】
电感两端的电压相位超前电流___。
A. 90°
B. 180°
C. 360°
D. 30°
【单选题】
电容两端的电压相位滞后电流___。
A. 30°
B. 90°
C. 180°
D. 360°
【单选题】
应用戴维南定理求含源二端网络的输入等效电阻是将网络内各电动势___
【单选题】
LC 选频振荡电路，当电路频率等于谐振频率时，电路性质为___。
A. 电阻性
B. 感性
C. 容性
D. 纯电容性
【单选题】
阻值为4Ω的电阻和容抗为3Ω的电容串联，总复数阻抗为___
A. 3+j4
B. 3-j4
C. 4+j3
D. 4-j3
【单选题】
电动势为10V，内阻为2Ω的电压源变换成电流源时，电流源的电流和内阻是___
A. 10A，2Ω
B. 20A，2Ω
C. 5A，2Ω
D. 2A，5Ω
【单选题】
电流为5A，内阻为2Ω的电流源变换成一个电压源时，电压源的电动势和内阻为___
A. 10V，2Ω
B. 2.5V，2Ω
C. 0.4V，2Ω
D. 4V，2Ω
【单选题】
额定电压都为220V的40W、60W、100W三灯泡串联在220V的电源中，它们的发热量由大到小排列为___
A. 100W 60W 40W
B. 40W 60W 100W
C. 100W 40W 60W
D. 60W 100W 40W
【单选题】
在正弦交流电的解析式i=ImSin(ωt +φ)中，φ表示___
A. 频率
B. 相位
C. 初相位
D. 相位差
【单选题】
正弦交流电压u=100Sin(628t + 600)V，它的最大值为___。
A. 100 V
B. 100 V
C. 60V
D. 628 V
【单选题】
能表示容性电路电压与电流关系的相量图是___。
【单选题】
电路中___定律指出：流入任意一节点的电流必定等于流出该节点的电流。
A. 欧姆
B. 基尔霍夫电流
C. 楞次
D. 基尔霍夫电压
【单选题】
已知电源电压为12 V ,四只相同灯泡的工作电压都是6 V，要使灯泡都能正常工作，则灯泡应___
A. 全部串联
B. 两只并联后与另两只串联
C. 两两串联后再并联
D. 全部并联
【单选题】
用戴维南定理分析电路“入端电阻”时，应将内部的电流源___处理。
【单选题】
任何一个含源二端网络都可以用一个适当的理想电压源与一电阻___来代替。
A. 串联
B. 并联
C. 串联或并联
D. 随意联接
【单选题】
用交流电流表测得交流电流10A，则电路中电流的最大值为___。
A. 10A
B. 14.1A
C. 20A
D. 70.7A
【单选题】
如右图所示电路中，已知各支路的电流I1=I2=10A， 则电路的总电流I为___。
A. 20A
B. 0 A
C. 14.1A
D. 50A
【单选题】
1杂质半导体中多数载流子的浓度取决于___
【单选题】
2在电场作用下，空穴与自由电子运动形成的电流方向___
【单选题】
4下列半导体材料哪一种的热敏性突出“导电性受温度影响最大”？___
A. 本征半导体
B. N型半导体质
C. P型半导体
【单选题】
5用万用表电阻挡检测某一个二极管时，发现其正、反电阻均近于1000KΩ，这说明该二极管是属于___。
A. 短路状态；
B. 完好状态；
C. 断路状态；
D. 极性搞错。
【单选题】
6稳压二极管是一个可逆击穿二极管，稳压时工作在___状态。
【单选题】
7三端集成稳压器CW7812的输出电压是___。
【单选题】
8三端集成稳压器CXX7805的输出电压是___
【单选题】
9一个平衡PN结，用导线将P区和N区连起来，而导线中___。
A. 有微弱电流
B. 无电流
C. 有瞬间微弱电流
【单选题】
10二极管两端正向电压大于___电压时，二极管才导通。
【单选题】
11当温度升高时，二极管的反向饱和电流 ___ 。
A. 增大；
B. 减小；
C. 不变；
D. 无法判定。
【单选题】
12硅二极管的正向导通压降比锗二极管的___ 。
推荐试题
【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
B. the preparing, compounding, and dispensing of medicines
C. dosage forms of medicines available
D. the therapeutic and other uses of medicines
【单选题】
(6) What is a main unique aspect of pharmacodynamics?___
A. Pharmacodynamics is an experimental medical science
B. Pharmacodynamics is focused on the characteristics of drugs
C. Pharmacodynamics borrows freely from both the subject matter and the experimenta techniques of physiology, biochemistry, microbiology, genetics and pathology
D. Pharmacodynamics correlates the entire field of preclinical medicine
【单选题】
7) What time of history does pharmacodynamics date back to?___
A. the second half of the seventeenth century
B. the second half of the eighteenth century
C. the second half of the nineteenth century
D. the second half of the twentieth century
【单选题】
8)What does the research on pharmacodynamics focus on?___
A. study of clinical effect of drugs
B. study of the process of drugs in the body
C. study of the effect and the mechanism of drugs on the body
D. study of the correlation of the actions and effects of drugs with their chemical structure
【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
C. part
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
D. giving
【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
B. make sure
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
B. assist with
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
D. biopharmaceutics
【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
B. absorption, distribution, metabolism, and excretion
C. metabolism and excretion
D. absorption and excretion
【单选题】
(4)Regarding the definition of bioavailability(BA), BA is related to___
A. total plasma drug concentration only
B. unbound drug concentration in the plasma
C. unbound drug concentration at the target site
D. total plasma drug concentration, and the administered drug dose
【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
B. i.v.infusion
C. Subcutaneous injection, transdermal and oral
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
C. Route of administration
D. All of above
【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.
【判断题】
Living cells break down glucose and fats to provide energy for other activities, which is called.
【判断题】
The right atriapumps deoxygenated blood to the lungs where it absorbs oxygen from the air.
【判断题】
The nervous system uses electrical signals to transmit information very rapidly to specific cells.
【判断题】
With the level of sodium increasing extracelular fruid. the cardiac muscle cells become too excitable and may contract.
【判断题】
A negative feedback loop is a control system that acts to maintain the level of some variables within a given range following a disturbance
【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.
【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.
【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.
【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.
【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.
【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.
【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.
