题目
题型：不详难度：来源：
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.
小题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. |
| 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. |
| 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. |
| 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. |
| 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 |
答案
小题1:D
小题2:C
小题3:B
小题4:D
小题5:B
解析
试题分析：来自不同地方的钻石可能看起来是一样的，如何识别宝石的家？这篇文章主要是介绍一种使用激光技术识别宝石来源的方法。
小题1:细节题：从文章第一段的句子：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.可知来自不同地方的钻石可能看起来是一样的，选D
小题2:细节题：从文章第三段的句子：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.可知为什么美国政府要求出售宝石的公司确定宝石的来源，是为了减少血矿石的交易。选C
小题3:细节题：从文章第五段的句子：but McManus and her team say that gemstones from the same area produce similar patterns.可知最能够帮助McManus和她的团队识别石头的来源的是来自同样地区的宝石有相似的光谱，选 B
小题4:细节题：从文章最后两段的句子：In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. 和“This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.可知激光技术将在识别矿物质的来源中带来革命性的改变，选D
小题5:写作意图题：从文章第二段的句子：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.可知作者写这篇文章主要是介绍一种使用激光技术识别宝石来源的方法。选B
核心考点
试题【Most people know precious gemstones (宝石) by their appearances. An emerald flashe】；主要考察你对题材分类等知识点的理解。[详细]
举一反三
But just what does it mean to say someone is “cool”? Most would answer that it is something to do with being independent-minded and not following the crowd.
Yale University art professor Robert Farris Thompson says that the term “cool” goes back to 15th century West African philosophy(哲学). “Cool” relates to ideas of grace(优雅) under pressure.
“In Africa, ” he writes, “coolness is a positive quality which combines calmness, silence, and life.”
The modern idea of “cool” developed largely in the US in the period after World War II. “Post-war ‘cool’ was in part an expression of war-weariness (n. 厌战情绪)
. . . it went against the strict social rules of the time,” write sociologists Dick Pountain and David Robins in Cool Rules:Anatomy of an Attitude.
But it was the American actor James Dean who became the symbol for “cool” in the hugely successful 1955 movie Rebel without a Cause. Dean plays a tough guy who disobeys his parents and the authorities. He always gets the girl, smokes cigarettes, wears a leather jacket and beats up bullies(欺凌弱小者). In the movie, Dean showed what “cool” would mean to American young people for the next 60 years.
Today the focus of “cool” has changed to athletics (体育运动) stars. Often in movies about schools, students gain popularity on the athletics field more than in the classroom. This can be seen quite clearly in movies like Varsity Blues and John Tucker Must Die.
But many teenagers also think being smart is cool. Chess and other thinking games have been becoming more popular in schools.
“Call it the Harry Potterization of America—a time when being smart is the new cool,” writes journalist Joe Sunnen.
小题1:Barack Obama, Lady Gaga and Steve Jobs are mentioned in the first paragraph to ________.
| A．introduce the topic | B．draw our attention |
| C．tell us what they have in common | D．tell us what is “cool” |
| A．thought and acted differently from the majority |
| B．had a calm and quiet attitude towards life |
| C．didn’t observe rules and authorities |
| D．had all kinds of “bad” manners |
| A．do very well in their studies |
| B．are very skilled at sports |
| C．are good at chess and other thinking games. |
| D．have supernatural powers like Harry Potter |
| A．It is generally considered “cool” to be independent-minded and not to follow the crowd. |
| B．“Cool” was used as early as the 15th century. |
| C．Disobeying one’s parents and the authorities is considered “cool” among American young people nowadays. |
| D．Getting the first place in an exam can also be considered “cool”. |
| A．The origin of the word “cool”. |
| B．The kinds of people who are “cool”. |
| C．The changing meaning of the word “cool”. |
| D．How to be a “ cool” person. |
Zhong Nanshan, a deputy to the NPC and a member of the CAE, said recently when the concentration of PM2.5 rises by 10 micrograms per cubic meter, hospitalization may rise by as much as 3.1 percent. Meanwhile, when the concentration of PM2.5 rises from 25 mgs per cubic meter to 200, the average daily death rate may rise to 11 percent.
Zhi Xiuyi, a leading expert in lung cancer treatment and also vice-president of the CATS, said medical authorities used to focus on tobacco control as a primary means of preventing lung cancer. "But in fact, air pollution is no less harmful than smoking and our research team released a report earlier this year showing that the cancer rate in Beijing is closely related to industrialization," he said.
The report, conducted by the Beijing Institute of Cancer Research, shows that the number of cancer patients in China has increased markedly during the past ten years. Chaoyang District, the city"s main area of industrialization, has the highest incidence of cancer, almost double that of Yanqing, an area on the outskirts of the city. About four out of 1000 Chaoyang residents have some form of the disease, with lung cancer at the top of the list.
"The risk of having cancer largely depends on the length of exposure and the concentration of noxious gases(有毒气体的浓度)," said Zhi. In response to the doubt whether seven years" exposure to poor air quality will almost result in cancer, Zhi said the time scale was taken from research overseas that suggested the rate of incidence generally peaked in the seventh year of exposure to a heavily polluted environment.
小题1: What is the passage mainly about?
| A．Medical researches on environment. |
| B．The disadvantages in big cities. |
| C．The only reason for the lung cancer. |
| D．Poor air quality contributing to lung cancer. |
| A．Compared with smoking, air pollution is more harmful. |
| B．Air pollution is as harmful as smoking. |
| C．It is very important to prevent people from smoking. |
| D．People realize the importance of keeping healthy. |
| A．16000 | B．12000 | C．8000 | D．7500 |
| A．Industrialization has its weakness as well as strengths. |
| B．The average death rate rises with different ages and places. |
| C．The air in Beijing is much more polluted than that in the other cities. |
| D．The more heavily-polluted air you breathe in, the sooner you’ll have cancer. |
Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis (光合作用)．Now researchers have found a way to imitate this seemingly simple process.
The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts (催化剂)．Similar to natural leaves，it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell，which uses those two materials to produce electricity，located either on top of a house or beside the house.
Though the leaf is only about the shape of a poker card，scientists claimed that it is promising to be an inexpensive source of electricity in developing countries. “One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology,” said Nocera at a conference of the American Chemical Society.
The artificial leaf is not a new idea. The first artificial leaf was invented in 1997 but was too expensive and unstable for practical use. The new leaf，by contrast，is made of cheap materials，easy to use and highly stable. In laboratory studies，Nocera showed that an artificial leaf prototype (原型) could operate continuously for at least 45 hours without a drop in activity.
The wonderful improvements come from Nocera"s recent discovery of several powerful，new and inexpensive catalysts. These catalysts make the energy transformation inside the leaf more efficient with water and sunlight. Right now，the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Besides，the device can run in whatever water is available；that is，it doesn"t need pure water. This is important for some countries that don"t have access to pure water.
With the goal to “make each home its own power station” and “give energy to the poor”，scientists believe that the new technology could be widely used in developing countries，especially in India and rural China.
小题1:Which of the following orders correctly shows how the artificial leaf is used to produce electricity?
a．artificial leaves split water into hydrogen and oxygen
b．the hydrogen and oxygen gases are stored in a fuel cell
c．the artificial leaves are put in water
d．the fuel cell uses hydrogen and oxygen to produce electricity
| A．c，a，b，d | B．c，b，a，d |
| C．b，c，a，d | D．c，a，d，b |
| A．build up more power stations in the world |
| B．provide cheaper energy for developing countries |
| C．offer people in developing countries access to pure water |
| D．gain a deeper understanding of the photosynthesis process |
| A．an introduction to the history of artificial leaves |
| B．a mixture of water power and solar energy |
| C．giving energy to the poor |
| D．an invention copying photosynthesis |
A study found that people decide where they stand based on a micro social status，established within seconds of entering the lift.
Rebekah Rousi．a Ph. D．student in cognitive(认知)science，conducted an ethnographic(人种论)
Study of elevator behaviour in two of the tallest office buildings in Adelaide，Australia.As part of her research，she took a total of 30 lift rides in the two buildings，and discovered .There was an established order to where people tended to stand
In a blog she writes that more senior men seemed to direct themselves towards the back of the elevator She said：“In front of them were younger men，and in front of them were women of aII ages.”She also notice there
was a difference in where people directed their gaze(注视)half way through the ride．“Men watched the monitors，looked in the side mirrors(in one building)to see themseIves．And in the door mirrors(of the other building)to also watch others Women would watch the monitors and avoid eye contact with other users(unless in conversation)and the mirrors，”she writes．
She concluded it could be that people who are shyer stand toward the front，where they can’t see other passengers，whereas confident people stand in the back，where they have a view of everyone else.
小题1:The passage is mainly about
A. elevator riding manners
B communication in the elevator
C. elevator riders’ standing positions
D. micro social status in the elevator
小题2:The underlined word“it”in the first paragraph probably refers to“ ”
| A．an elevator | B．the new research | C．eye contact | D．social status |
A confident B shy C honest
小题4:The conclusion of the research in the passage is
A. subjective B．objective C critical D doubtful
I found the description in the 2003 book When Smoke Ran like Water，by epidemiologist(流行病学家)and environmental advocator(倡导者)Devra Davis．In it,Davis looks back at several historic pollution events and their disastrous effect on human human health-and at how these phenomena were often Ignored or even actively covered up by then people in charge at that time.
As Davis points out，John Evelyn was ahead of his time when writing about how London’s polluted air affected the well-being of its residents．It wasn’t until nearly 300 years later,after what became well-known as the Great Smog of 1952，that the government began to address the problem in a systematic way．
For four days．Between December 5th“and 9th“，due to all accident of the weather pattern，the city was buried in a heavy fog .People were still burning coal for fuel，and low-grade coal at that time， because 0f wartime condition．A temperature inversion(转向)trapped the smoke from the city’s fires， creating a black cloud in which people could barely find their way down the most familiar streets
Some tried to protect themselves，but most people simply went about their business. But l952’s fog was far worse than any other in memory．In the same week of the previous year, 1852 people had died in London；inl952，that number was 4703 And the deaths didn’t stop when the weather changed and the fog lifted．Davis and her colleagues analyzed data from the next several months and found that about 13000 more people died between December and March than one would have predicted from historical averages Many of them died of pneumonia(肺炎)．The government，she writes．Tried to blame a bad flu season．Her detailed analysis found that explanation simply did
not pan out．
Davis writes that even today in this country ,we still have not completely absorbed the lessons of similar events．Sixty years the killer fog lifted in London，people are dying preventable deaths and suffering life．changing illnesses，simply because they must breathe the air of the cities where they live
小题1:The passage is written to
| A．warn people of the danger from air pollution |
| B．introduce London’s Great Smog of l952 |
| C．blame the government for the smog |
| D．explain the reasons for air pollution |
| A．imaginary | B．adventurous | C．unbelievable | D．annoying |
| A．people burned wood for fuel |
| B．a forest fire created a black cloud over the city |
| C．the government ignored the smog |
| D．most people went abouttheirbusine00 |
A. lndifferent B Concerned C．Hopeless．D. Panic
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