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A．mentally B．artificially C．manually D．automatically
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A．financial B．original C．social D．historical
Superconducting Ceramic (陶瓷)
An underground revolution begins thiswinter. With the flip (轻击) of a switch,30,000homes in one part of Detroitwill soon become the first in the country to receive electricity transmitted byice-cold high-performance cables. Other American cities are expected to follow Detroit's example in theyears ahead, which could conserve enormous amounts of power.
The new electrical cables at the Frisbiepower station in Detroitare revolutionary because they are made of superconductors. A superconductor isa material that transmits electricity with little or no resistance. Resistanceis the degree to which a substance resists electric current. All commonelectrical conductors have a certain amount of electrical resistance. Theyconvert 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. Asuperconducting material has to be cooled to an extremely low temperature tolose 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 theFrisbie station is made of a ceramic materialthat contains copper, oxygen, bismuth (铋), strontium (锶), andcalcium (钙). A ceramic is a hard, strong compound madefrom clay or minerals. The superconducting ceramic has been fashioned into atape that is wrapped lengthwise around a long tube filled with liquid nitrogen.Liquid nitrogen is supercold and lowers the temperature of the ceramic tape tothe point where it conveys electricity with zero resistance.
The United States loses an enormousamount of electricity each year to resistance.Because cooled superconductorshave no resistance, they waste much less power.Other cities are watching theFrisbie experiment in the hope that they might switch to superconducting cableand conserve power, too.
第 31 题 What is the benefit of the revolutionmentioned in the first paragraph？
Amanda Symcheck was having a party in the basement when the StOrm began.
Science and Truth
"FINAGLE" (欺骗)is not a word that most people associate with science. One reason is that the image of the scientist is of one who always__________ (51) data in an impartial (不偏不倚的) search for truth. In any debate --_________(52) intelligence,schooling,energy -- the phrase "science says" usually disarms opposition.
But scientists have long acknowledged the existence of a "finagle factor'—a tendency by many scientists to give a helpful change to the data to__________ (53)desired results. The latest of the finagle factor in action comes from Stephen Jay Gould, a Harvard biologist, who has__________ (54) the important 19th century work of Dr.Samuel George Morton. Morton was famous in his time for analysing the brain__________ (55) of the skulls as a measure of intelligence. He concluded that whites had the largest brains, that the brains of Indians and blacks were smaller, and __________ (56), that whites constitute a superior race.
Gould went back to Morton's original data and concluded that the__________ (57)were an example of the finagle at work. He found that Morton's "discovery" was made by leaving out embarrassing data, __________ (58) incorrect procedures, and changing his criteria -- again, always in favour of his argument. Morton has been thoroughly discredited by now and scientists do not believe that brain size reflects __________ (59).
But Gould went on to say Morton's story is only an example of a common problem in __________ (60) work. Some of the leading figures in science are__________ (61) to have used the finagle factor. Gould says that Isaac Newton fudged out (捏造) to support at least three central statements that he could not prove. And so __________ (62)Laudius Ptolemy, the Greek astronomer, whose master work, Almagest, summed up the case for a solar system that had the earth as its centre. Recent__________ (63)indicate that Ptolemy either faked some key data or resorted heavily to the finagle factor.
All this is import.ant because the finagle factor is still at work. For example, in the artificial sweetener controversy, for example, it is__________ (64) that all the studies sponsored by the sugar industry find that the artificial sweetener is unsafe, __________ (65) all the studies sponsored by the diet food industry find nothing wrong with it.
第 51 题
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