题目内容

A technique that controls immediate gas explosions by spraying them with large droplets of water is being tested by scientists at the University of Wales, United Kingdom.Instead of using the traditional fine water sprays when a gas leak is detected, the researchers have discovered that large droplets help to draw in some of the force of any explosion and provide a better way of controlling fire.

The research is based on studies made of the Piper Alpha oil rig (油井) explosion that occurred in the North Sea nine years ago killing 167 workers.The Welsh team found that by covering the gas-leak area with water droplets, the explosion and its effect can be greatly reduced.

Dr Gerand Thomas, a good lecturer in physics at the university’s Center for Explosion Studies, said that it was impossible to deal with gas explosions in the same way as fires because the whole event may only last a quarter of a second and normal water sprays do not have time to be effective.

Using the droplets of water to hold explosions resulted in the water being turned into a mist that allows some force of the explosion to be reduced.The mist slows down the combustion (燃烧) process and can stop a large amount of the gas igniting (点火,燃烧), thus greatly reducing damage by limiting pressure development.With such a system, the operator has to decide at what point after a gas leak to activate the sprays.

The Center for Explosion Studies is the first of its kind in the UK and has been purposely-built for the study and implication of industrial explosions on land and sea.Research is developed to the causes of accidental explosions and they might be prevented.Full-sized imitative buildings can be built at the center where explosions and fires are created to test preventative equipment using sensors to monitor their efficiency.

Another area that the Welsh researchers have been looking at is how materials respond to explosions.The center also carries out research requested by individual customers.

Which of the following would be the best title for the passage?

     A.Piper Alpha Oil Rig Explosion

     B.Large Droplets of Water

     C.A New Way of Controlling Gas Explosions

     D.The center for Explosion Studies

The research finds that _____ in holding immediate explosion.

     A.small water sprays are better than large droplets of water

     B.small water sprays are not as good as large droplets of water

     C.both small water sprays and large droplets of water are good

     D.neither small water sprays nor large droplets of water is good

Dr Geraint Thomas implies that ______.

     A.normal water sprays can put out fire effectively

     B.gas explosions break out more quickly than fires

     C.fires are easier to be held than explosions

     D.gas explosions break out so quickly that there is no way to control it

Which of the following is not included in the research area of the Center for Explosion Studies?

     A.To test the result of gas explosion.

     B.To get some implications of industrial explosions on land and sea.

     C.To find out how materials respond to explosions.

    D.To find out when material respond to explosions.

【小题1】C

【小题2】B

【小题3】B

【小题4】A


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In the 1960s, many young Americans were dissatisfied with American society. They wanted to end the Vietnam War and to make all of the people in the U.S. equal. Some of them decided to "drop out" of American society and form their own societies. They formed utopian communities, which they called “communes”, where they could follow their philosophy of “do your own thing”. A group of artists founded a commune in southern Colorado called "Drop City." Following the ideas of philosopher and architect Buckminster Fuller, they built dome-shaped houses from pieces of old cars. Other groups, such as author Ken Kesey’s Merry Pranksters, the followers of San Francisco poet Steve Gakin, and a group that called itself the Hog Farm, lived in old school houses and traveled around the United States. The Hog Farm became famous when they helped organize the Woodstock Rock Festival in 1969. Steve Gaskin’s followers tried to settle down on a farm in Tennessee, but they had to leave when some members of the group were arrested for growing marijuana.

  Not all communes believed in the philosophy of “do your own thing”. However, Twin Oaks, a commune founded in Virgiania in the late 1960s, was based on the ideas of psychologist B.F.Skinner. The people who lived at Twin Oaks were carefully controlled by Skinner’s “conditioning” techniques to do things that were good for the community. In 1972, Italian architect Paolo Soleri began to build Arcosanti, a utopian city Arizsona where 2500 people will live closely together in one large building called an “archeology”. Soleri believes that people must live closely together so that they will all become one.

Why did some young Americans decide to “drop out” of society during the 1960s?

  A. They were not satisfied with American society.

  B. They wanted to grow marijuana.

  C. They wanted to go to the Vietnam War.

  D. They did not want all people to be equal.

Where did the members of the Hog Farm commune live?

  A. In dome-shaped house.         B. In old school houses.

  C. On a farm in Tennessee.        D. In an archeology in Arizona.

Who gave the people of Drop City the idea to build dome-shaped house?

  A. Paolo Soleri.                B. B.G.Skinner.

  C. Steve Gaskin.                D. Buckminster Fuller.

What was the Twin Oaks commune based on?

  A. The philosophy of “do your own thing”.

  B. Virginia in the late 1960s.

  C. The ideas of psychologist.

  D. The belief that people must live closely together.

What is an “archeology”?

  A. A person who studies archaeology.

  B. A large building where people live closely together.

  C. A city in Arizona.

  D. A technique to control people.

It’s impossible to determine how many people would have lost their lives without the contribution of African-American inventor Dr Charles Drew.
Charles Drew was born on June 3, 1904, in Washington, DC. His early interest was in education, but he was also an outstanding athlete. While in college, he was awarded as the man who contributed the most to sports during his four years in school. Drew’s sister Elsie suffered from tuberculosis(肺结核) and died in 1920. Her death influenced his decision to study medicine.
After becoming a doctor and working as a college instructor, Drew went to Columbia University, where he earned his Doctor of Medical Science degree. During this time he became involved in research on blood and blood transfusions.
At Columbia, he wrote a paper on “banked blood”, in which he described a technique he developed for the long-term preservation of blood plasma. Before his discovery, blood could not be stored for more than two days because of the rapid breakdown of red blood cells. Drew had discovered that by separating the plasma from the whole blood and then refrigerating them separately, they could be combined a week later for a blood transfusion. Drew became the first African American to receive a PhD in medical science.
After World War II broke out, Drew was called upon to put his techniques into practice. He was named a project director for the American Red Cross but soon quit his post after the government issued an order that blood taken from white donors should be separated from that of black donors.
On April 1, 1950, after he attended the annual free clinic at the John A. Andrew Memorial Hospital, he and other three physicians decided to drive back home. As he was tired from spending the night before in the operating room, he lost control of his car. Drew was badly injured and was taken to Alamance General Hospital in Burlington, North Carolina. He was pronounced dead half an hour after he first received medical attention. Drew's funeral was held on April 5, 1950, at the Nineteenth Street Baptist Church in Washington, DC.
But contrary to popular thought, he was not refused a blood transfusion by an all-white hospital. He indeed received a transfusion but was beyond the help of the doctors attending to him. As Dr. John Ford, one of the doctors who survived the accident, later explained, “We all received the very best of care. The fact that he was a Black did not in any way limit the care that was given to him.” Over the years, Drew has been considered one of the most honored figures in the medical field.
【小题1】According to the passage, ________ might have contributed to the invention of blood banks.

A.the combination of blood cells
B.the rapid breakdown of red blood cells
C.the development of refrigerating technique
D.the technique of separating plasma from the whole blood
【小题2】By saying “contrary to the popular thought” in the last paragraph, the writer _______.      
A.can’t understand the doctors’ decision
B.indicates his concern about the popular thought
C.feels disappointed with the all-white hospital
D.means what the doctors did was out of expectation
【小题3】We can learn from the passage that Dr Charles Drew is best remembered by people as _______.       .
A.an outstanding athleteB.a college instructor
C.a medical researcherD.a project director
【小题4】What conclusion can we draw from the passage?
A. Charles Drew died in a medical accident.
B. African Americans were still treated unfairly in the 1940s.
C. Charles Drew was the first African American to receive a PhD.
D. Physicians refused to give Charles Drew medical attention because he was a black.
【小题5】In which section of a magazine can we most probably find the passage?
A.PeopleB.HealthC.CultureD.Entertainment

Books are not Nadia Konyk's thing. Her mother brings them home from the library, but Nadia rarely shows interest. Instead, like so many other teenagers, Nadia, 15, is addicted to the Internet. She regularly spends at least six hours a day in front of the computer, spending most of her time reading and commenting on stories written by other users. Her mother, Deborah Konyk, would prefer that Nadia read books for a change.
As teenagers' scores on reading tests have declined, some argue that the hours spent surfing the Internet are the enemy of reading—destroying a precious common culture that exists only through the reading of books. Critics have warned that electronic media would destroy reading.
Others say the Internet has created a new kind of reading. The Web inspires a teenager like Nadia, who might otherwise spend most of her leisure time watching television, to read and write. What is different now, some literacy experts say, is that spending time on the Web engages viewers with text.
Web supporters believe that strong readers on the Web may eventually surpass those who rely on books. Reading five Web sites, experts say, can be more enriching than reading one book. "It takes a long time to read a 400-page book," said Spiro. "In a tenth of the time," he said, the Internet allows a reader to "cover a lot more of the topic from different points of view."
Some literacy experts say that reading itself should be redefined. Interpreting videos or pictures, they say, may be as important a skill as analyzing a novel or a poem. "Kids are using sound and images so they have a world of ideas to put together," said Donna Alvermann, a professor of literacy education at the University of Georgia. "Books aren't out of the picture, but they're only one way of experiencing information in the world today."
Next year, the Organization for Economic Cooperation and Development, which gives reading, math and science tests to 15-year-old students in more than 50 countries, will add an electronic reading component(软件). The United States says it will not participate because an additional test would overburden schools.
【小题1】Why are books not the thing of Nadia Konyk?

A.She does reading mainly through electronic media.
B.Her mother doesn’t provide her with enough books.
C.She has become addicted to playing games on the web.
D.Like many youngsters, she has lost interest in reading.
【小题2】How many hours does Nadia spend in front of the computer in a week?
A.Exactly forty-two hoursB.Usually fifty hours
C.More than forty hoursD.At most thirty-six hours
【小题3】Which of the following statements is correct according to the passage?
A.To search for information on the web engages viewers without text.
B.To explain videos is a technique more important than analyzing a novel.
C.Children using sound and images may lose their interest in movies.
D.People reading well online may surpass those who rely on books.
【小题4】Why did the US refuse to participate in the tests with an added electronic reading component?       It is because ______.
A.the teachers and students considered it useless
B.such a test would give schools more extra work
C.they thought reading was the only way to get information
D.none of them showed interest in such an additional test

If you want to improve your child’s results at school, you could do a lot worse than ensuring that they do plenty of exercise. Scientists have already shown that physical activity can make you brainier. But a team in America has used scans to show that an important part of the brain actually grows in children who are fit. These youngsters tend to be more intelligent and have better memories than those who are inactive.
  Scientists also found that one of the most important parts of their brains was 12 percent larger than those of unfit children. They believe that encouraging children to take exercise from a very young age could help them do better at school later. Researchers from the University of Illinois, in the U.S., studied the brains of 49 children aged nine and ten using a magnetic resonance imaging scan (核磁共振摄影扫描), a technique which provides very detailed pictures of organs and tissues in the body.
  They also tested the fitness levels of the children by making them run on a treadmill (跑步机). The scientists found that the hippocampus, a part of the brain responsible for memory and learning, was around 12 percent larger in the fitter children.
  Professor Art Kramer, who led the study published in the journal Brain Research, said the findings had important implications for encouraging individuals to take part in sport from a young age. “We knew that experience and environmental factors and socioeconomic status all impact brain development,” he said. “If you get some terrible genes from your parents, you can’t really fix that, and it’s not easy to do something about your economic status. But here’s something that we can do something about.”
【小题1】 If you want to improve your children’s result in school, ____________.

A.it is worse to ensure that they do plenty of exercise
B.you can have their brain scanned
C.it could be better to make sure that they do a lot of exercise
D.you can do a lot except ensuring that they do exercise
【小题2】 According to the passage, which of the following statements is NOT true?
A.The fitness level of the children is linked to their intelligence.
B.Children who have a larger hippocampus will probably have better memories.
C.You can do something about the genes from your parents.
D.Unhealthy children will probably have a smaller hippocampus than others.
【小题3】All the following factors that have some influence on one’s brain are mentioned EXCEPT ____________.
A.genetic factorB.economic statusC.physical fitnessD.economic development

Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.

Beneath the surface of a gemstone, on the tiny level of atoms and molecules(分子), lie clues (线索) to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.

Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.

To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles(微粒)called electrons separate from atoms.

The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements(元素)produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.

In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.

Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.

1.We learn from Paragraph 1 that __________________.

A. an emerald and a ruby are names of diamonds.

B. it’s not difficult to tell where the gem was mined.

C. appearances help to identify the origin of gemstones.?

D. diamonds from different places may appear the same.

2.Why did the U.S. government pass law that requires companies selling gemstones to determine the origins of their stones?

A. To look for more gemstones.?????????????

B. To encourage violent civil wars.

C. To reduce the trade in blood minerals.??????

D. To develop the economy.

3.Which of the following facts most probably helps McManus and her team in identifying the origin of stones?

A. Heat can turn ice into water or water into steam.

B. Gemstones from the same area produce similar light patterns.

C. Laser can changes a miniscule part of the gemstone into plasma.

D. Materialytics has already collected patterns from thousands of gemstones.

4.From the last two paragraphs, what can be inferred about the laser technique?

A. It is ready for commercial use.

B. People can use the new tool to find more gemstones.

C. It can significantly reduce the gemstones trade in blood minerals.

D. It will bring about a revolutionary change in identifying the origin of minerals.

5.The author wrote this passage mainly to ________.

A. tell us how to identify the origin of diamonds.

B. introduce a laser technique in identifying a stone’s origin

C. prove identifying the origin of gemstones are difficult

D. attract our attention to reducing trade in blood minerals

 

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