题目
题型：江苏同步题难度：来源：
across an alternative source of clean energy to rival wind and solar power.
The breakthrough, which scientists say is the first new way to generate electricity in 160 years, could
lead to batteries that use water instead of poisonous substances.
The scientists made the discovery when they were investigating what happens when tap water is
forced through extremely narrow glass tubes. Water squeezed down the tubes, each of which was
narrower than a tenth the thickness of a human hair, generating a small electric current that ran the length
of the tube. To produce a larger electric current, the team tried forcing water through a glass water filte
r(滤水器) that contained thousands of narrow channels lined up side by side. "When we took a syringe (注射器) of water and squeezed it through the filter, we got enough power to light a light bulb," said
Larry Kostiuk of the University of Alberta in Canada. "The harder you push the syringe, the more electric
current you get."
The current is produced because of an effect in the glass tubes. When they are filled with water,
positively charged ions (阳离子) fixed in the tubes are washed away, leaving a slight negative charge on
the glass surface. When water is then forced along the tube, the surface repels negatively charged ions in
the water while positively charged ions are attracted down the tube. The result is a net flow of positively
charged ions that sets up an electric current.
According to Dr Kostiuk, no one has ever thought to use water to produce electricity in this way.
"The last time someone came up with a way of generating electricity was Michael Faraday in 1839," he
said. "So this is the first new way of generating electricity in 160 years, which is why we are so excited
about it."
Dr Kostiuk says water batteries might one day be used to power mobile phones and calculators, but
admitted that the engineering challenges might make other applications more realistic. "You"d need to be
sure it wouldn"t leak, and you"d need to make sure it wouldn"t freeze," he said.
More likely would be to install the electricity-generating devices where water is already being pumped, such as at city water filtration sites, he said. "It could compete with wind and solar power," he added.
B. A kind of new energy source found in tap water.
C. The breakthrough to generate electricity 160 yeas ago.
D. A kind of new battery invented without poisonous substances.
B. identifies
C. attracts
D. rebels
B. They could make an electric current to light a light bulb.
C. Their discovery could be used to invent water batteries.
D. Their discovery was made 160 years earlier than Faraday"s.
B. They have some possible disadvantages like water leaking.
C. They would be needed greatly at city water filtration sites.
D. They would be better than wind and solar power.
答案
核心考点
试题【阅读理解。 Scientists who discovered a new way of generating electricity from wat】；主要考察你对题材分类等知识点的理解。[详细]
举一反三
S.D., so commuting (经常往返) to class isn"t the problem. But he doesn"t like lectures much, isn"t a
morning person, and wants time during the day to restore motorcycles.
So Steele, a full-time senior business major, has been taking as many classes as he can from the
South Dakota State system"s online offerings. He gets better grades and learns more, he says, and
insists he isn"t missing out on the college experience.
"I still know a lot of people from my first two years living on campus, and I still meet a lot of people,"
he says. But now, he sets his own schedule.
At least 2.3 million people took some kind of online courses, according to a recent survey by The
Sloan Consortium, an online education group, and two-thirds of colleges offering "face-to-face" courses
also offer online ones. But what were once two different types of classes are looking more and more
alike and often falling into the same pool of students.
At some schools, online courses originally intended for non-traditional students living far from campus
have proved surprisingly popular with on-campus students. A recent study found 42 percent of the
students enrolled (登记) in its distance education courses were located on campus at the university that
was hosting the online courses.
Numbers vary depending on the policies of particular colleges, but other schools also have students
mixing and matching online and "face-to-face" credits. Motives range from lifestyle to adapting a job
schedule to getting into high-demand courses.
Washington State had about 325 on-campus undergraduates taking one or more distance courses last
year. As many as 9,000 students took both distance and in-person classes at Arizona State last year.
"Business is really about providing choices to their customers, and that"s really what we want to do,"
said Sheila Aaker, extended services coordinator (协调人) at Black Hills State.
Many schools, such as Washington State and Arizona State, let departments and academic units
decide who can take an online course. They say students with legitimate academic needs-a conflict with
another class, a course they need to graduate that is full-often get permission, though they still must take
some key classes in person.
B. To tell us about the development of campus courses.
C. To show the differences between campus courses and online courses.
D. To show more on-campus students are taking online courses.
B. knows none of his classmates
C. wants to have his own lifestyle
D. doesn"t get good marks
B. It is expected that distance education is popular with on-campus students.
C. About 325 on-campus undergraduates took online courses in Washington last year.
D. Different colleges have different policies about online courses.
B. colleges should provide more majors for students
C. where the similarity between business and colleges lies
D. why colleges offer online courses to on-campus students
you probably sing or whistle when you are happy.
Some scientists believe that birds do sing some of the time just because they are happy. However,
they sing most of the time for a very different reason. Their singing is actually a warning to other birds to
stay out of their territory.
Do you know what a "territory" is? A territory is an area that an animal, usually the male, claims as its
own. Only he and his family are welcome there. No other families of the same species are welcome.
Your yard and house are your territory where only your family and friends are welcome. If a stranger
should enter your territory and threaten you, you might shout. Probably this would be enough to frighten
him away.
If so, you have actually scared the stranger away without having to fight him. A bird does the same
thing. But he expects an outsider almost any time, especially at nesting season. So he is screaming all the
time, whether he can see an outsider or not. This screaming is what we call a bird"s song, and it is usually
enough to keep an outsider away.
Birds sing loudest in the spring when they are trying to attract a mate and warn others not to enter the
territory of theirs.
You can see that birds have a language all their own. Most of it has to do with attracting mates and
setting up territories.
B. a way of warning
C. an expression of anger
D. a way of greeting
B. A place where a bird may shout at the top of its voice.
C. An area for which birds fight against each other.
D. An area which a bird considers to be its own.
B. Because their singing helps frighten outsiders away.
C. Because they want to find outsiders around.
D. Because their singing helps get rid of their fears.
B. By reporting experiment results.
C. By describing birds" daily life.
D. By telling a bird"s story.
technique that could help track the movements of criminal suspects or unidentified murder victims.
The method relies on measuring how chemical variations in drinking water show up in people"s hair.
"You"re what you eat and drink, and that"s recorded in your hair," said Thure Cerling, a geologist at
the University of Utah.
While U.S diet is relatively identical, water supplies vary. The differences result from weather patterns. The chemical composition of rainfall changes slightly as rain clouds move.
Most hydrogen and oxygen atoms in water are stable, but traces of both elements are also present as
heavier isotopes (同位素). The heaviest rain falls first. As a result, storms that form over the Pacific
deliver heavier water to California than to Utah.
Similar patterns exist throughout the U.S. By measuring the proportion of heavier hydrogen and
oxygen isotopes along a strand of hair, scientists can construct a geographic timeline. Each inch of hair
corresponds to about two months.
Cerling"s team collected tap water samples from 600 cities and constructed a map of the regional
differences. They checked the accuracy of the map by testing 200 hair samples collected from 65 barber
shops. They were able to accurately place the hair samples in broad regions roughly corresponding to
the movement of rain systems.
"It"s not good for pinpointing (精确定位)," Cerling said. "It"s good for eliminating many possibilities."
Todd Park, a local detective, said the method has helped him learn more about an unidentified woman whose skeleton was found near Great Salt Lake.
The woman was 5 feet tall. Police recovered 26 bones, a T-shirt and several strands of hair.
When Park heard about the research, he gave the hair samples to the researchers.
Chemical testing showed that over the two years before her death, she moved about every two
months.
She stayed in the Northwest, although the test could not be more specific than somewhere between
eastern Oregon and western Wyoming.
"It"s still a substantial area," Park said "But it narrows it way down for me."
B. A person"s hair may reveal where they have lived.
C. Hair analysis accurately identifies criminal suspects..
D. The chemical composition of hair varies from person to person.
B. Food and drink preferences vary with individuals.
C. Food and drink leave traces in one"s body tissues.
D. Food and drink are essential to one"s existence.
B. The water it delivers becomes lighter when it moves inland.
C. Its chemical composition is less stable than in other areas.
D. It gathers more light isotopes as it moves eastward.
B. It helps the police determine where a crime is committed.
C. It helps the police narrow down possibilities in detective work.
D. It helps identify the drinking habits of the person under investigation.
It is not that newspapers are a necessity. Even now some people get most of their news from television or
radio. Many buy a paper only on Saturdays or Sundays. But for most people,reading a newspaper has
become a habit passed down from generation to generation.
The nature(特征) of what is news may change. What basically makes news is what affects our
lives-the big political stories,the coverage(报道) of the wars,earthquakes and other disasters,will
continue much the same. I think there will be more coverage of scientific research,though,the research
happening in areas that may directly affect our lives,like genetic(基因) engineering. In the future,I think
there will be more coverage of scientific explanations of why we feel as we do-as we develop a better
understanding of how the brain operates and what our feelings really are.
It"s quite possible that in the next century,newspapers will be transmitted (传输)electronically from
the Fleet Street and printed out in our own home. In fact,I"m pretty sure how it will happen in the future.
You will probably be able to choose from a menu and make up your own newspaper by picking out the
things you want to read-say,sports,international news,ect.
I think people have got it wrong when they talk about competition between the different media. They
actually feed-off(依靠) each other. Some people once foresaw(预见) that television would kill off
newspapers,but that hasn"t happened. What is read on the printed page lasts longer than pictures flashed
up on a screen or sounds lost in the air. And as for the Internet,it"s never really pleasant to read something
just on a screen.
B. The Changes of Media
C. Make Your Own Newspaper
D. The Future of Newspaper
B. newspapers will not be printed in publishing houses any longer
C. newspapers will cover more scientific research
D. more and more people will read newspapers
B. A menu of important news.
C. The most important news.
D. What you are interested in.
庭的) DNA testing so that an individual can be identified by a single cell.
Ian Findlay, from the Australian Genome Research Facility at the University of Queensland, said
current DNA testing required 200 to 500 cells to gain a similar level of accuracy. "What we have done
has brought that down to one cell," Dr Findlay said after releasing details of his DNA testing technique
at a Sydney conference.
The technology could allow investigators to pick up DNA identities from plastic cards and even build
up a complete history of the people who have handled a paper document.
"You"d have to wear a space suit to stop yourself from leaving traces. You can identify cells on the
paper, so you can work out where it"s come from and who"s touched it," he said.
The technique could also be used to trace the thrower of a punch (打孔) from cells left behind on the
skin of their victim. Even the wearing of latex(橡胶)gloves would not help: small cells can pass through
the gloves, and the constant flow of genetic material given off by the human body would leave further
evidence.
"We gained a skin cell from a document dating back 30 years and managed to gain a DNA
fingerprint. DNA evidence can remain fresh for decades, perhaps even centuries," Dr Findlay said. "The
potential for this technology to solve unsolved crimes is great, "he said.
But Dr Findlay, named scientist of the year in 1998 by the European Society of Human Genetics, said
the new testing needed to be scientifically validated, which would take up to five years.
He said, "There are serious consequences taking on technologies too early. The public has to be sure
that they have the utmost confidence in the security and court systems."
B. a single cell can identify an individual
C. a higher level of accuracy can be acquired with a single cell
D. it needs less than 200 cells to gain a certain level of accuracy
B. imagined good
C. supposed commonly
D. criticized strongly
B. make the process of DNA testing much more simplified
C. help to pick up DNA identities more easily
D. be widely used in five years at most
B. the public have acknowledged the new testing technology
C. it is safe to put the new technology into use now
D. Dr Findlay is quite sure of his new technology
B. inform us of the wide use of DNA testing
C. report a piece of interesting news
D. tell us a recent improvement in DNA testing
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