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抗药性(resistance)
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参考解析
解析：病原体经长期应用化疗药物后对药物反应性降低。
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Please explain how we describe the resistance in semiconductor. Compare the resistance of a metal,poly and diffusion in tranditional CMOS process.（威盛笔试题circuit design-beijing-03.11.09）
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共用题干
第二篇Superconducting Ceramic（陶瓷）An underaround revolution beqins this winter. With the flip（轻击）of a switch, 30,000 homes in one part of Detroit will soon become the first in the country to receive electricity transmitted by ice-cold high-performance cables.Other American cities are expected to follow Detroit's example in the years ahead,which could conserve enormousamounts of rower.The new electrical cables at the Frisbie power station in Detroit are revolutionary because they are made of superconductors.A superconductor is a material that transmits electricity with little or no resistance.Resistance is the degree to which a substance resists electric current.All common electrical conductors have a certain amount of electrical resistance.They convert at least some of the electrical energy passing through them into waste heat.Superconductors don't.No one understands how superconductivity works.It just does.Making superconductors isn't easy.A superconducting material has to be cooled to an extremely low temperature to lose its resistance.The first superconductors,made more than 50 years ago,had to be cooled to -263 degrees Celsius before they lost their resistance.Newer superconducting materials lose their resistance at-143 degrees Celsius.The superconductors cable installed at the Frisbie station is made of a ceramic material that contains copper,oxygen,bismuth（秘）,strontium（锶）and calcium (钙）.A ceramic is a hard,strong compound made from clay or minerals.The superconducting ceramic has been fashioned into a tape that is wrapped lengthwise around a long tube filled with liquid nitrogen.Liquid nitrogen is supercold and lowers the temperature of the ceramic tape to the point where it conveys electricity with zero resistance.The United States loses an enormous amount of electricity each year to resistance. Because cooled superconductors have no resistance,they waste much less power. Other cities are watching the Frisbie experiment in the hope that they might switch to superconducting cable and conserve power,too.Compared to common electrical conductors,superconductorsA:have little or no electrical resistance.B:can be used for a long time.C:are not energy-efficient.D:can be made easily.
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MRC是什么的缩写？（）A、Modular Radio ConnectB、Modular Resistance CabinetC、Modular Radio CabinetD、Modular Resistance Connect
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According to Ohm’s Law， which of the following is correct？（）A、As voltage increases， resistance decreasesB、As amperage decreases， resistance decreasesC、As resistance decreases， amperage increasesD、As resistance increases， voltage increases
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When replacing a power supply， what MUST the technician observe？（）A、voltageB、currentC、wattageD、resistance
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单选题If a voltmeter is connected across a line, it must be protected with a（）A
shuntB
high-resistance coil in the armature circuitC
low-resistance coil in the armature circuitD
shunt and a coil of high resistance
考题
单选题For practical purposes, in a simple series circuit, the source voltage will be dropped across one resistor if it has（）.A
half the resistance of the other resistorB
a resistance equal to the otherC
at least ten times the resistance of the otherD
a partial short circuit
考题
单选题According to Ohm’s Law， which of the following is correct？（）A
As voltage increases， resistance decreasesB
As amperage decreases， resistance decreasesC
As resistance decreases， amperage increasesD
As resistance increases， voltage increases
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单选题Which of the following statements is true concerning simple parallel resistance circuits?（）A
The total current flow equals the sum of the individual currentsB
The total current flow equals the reciprocal of the sum of the individual currentsC
The total resistance equals the sum of the individual resistanceD
The total voltage equals the sum of the individual voltages across each resistance
考题
单选题A resistance in a circuit of unknown value is to be tested using the voltmeter/ammeter methodTherefore, the meters should be connected with（）.A
both meters in series with the resistanceB
both meters in parallel with the resistanceC
the ammeter in series and the voltmeter in parallel with the resistanceD
the ammeter in parallel and the voltmeter in series with the resistance
考题
单选题Most conducting materials such as copper, aluminum, iron, nickel, and tungsten （）.A
increase in resistance with increased temperatureB
increase in resistance with decreased temperatureC
decrease in resistance with increased temperatureD
increase in conductance with increased temperature
考题
名词解释题非寄主抗性（non-host-resistance）
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