Most people know precious gemstones (寶石) 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 (線索) 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.
【小題1】We learn from Paragraph 1 that __________________.
| A．a(chǎn)n emerald and a ruby are names of diamonds. |
| B．it’s not difficult to tell where the gem was mined. |
| C．a(chǎn)ppearances 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．a(chǎn)ttract our attention to reducing trade in blood minerals |
【小題1】D
【小題2】C
【小題3】B
【小題4】D
【小題5】B
解析試題分析：來自不同地方的鉆石可能看起來是一樣的，如何識別寶石的家？這篇文章主要是介紹一種使用激光技術(shù)識別寶石來源的方法。
【小題1】細節(jié)題：從文章第一段的句子：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.可知來自不同地方的鉆石可能看起來是一樣的，選D
【小題2】細節(jié)題：從文章第三段的句子：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.可知為什么美國政府要求出售寶石的公司確定寶石的來源，是為了減少血礦石的交易。選C
【小題3】細節(jié)題：從文章第五段的句子：but McManus and her team say that gemstones from the same area produce similar patterns.可知最能夠幫助McManus和她的團隊識別石頭的來源的是來自同樣地區(qū)的寶石有相似的光譜，選 B
【小題4】細節(jié)題：從文章最后兩段的句子：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.可知激光技術(shù)將在識別礦物質(zhì)的來源中帶來革命性的改變，選D
【小題5】寫作意圖題：從文章第二段的句子：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.可知作者寫這篇文章主要是介紹一種使用激光技術(shù)識別寶石來源的方法。選B
考點：考查科普類短文
科目：高中英語 來源： 題型：閱讀理解
It is difficult for doctors to help a person with a damaged brain. Without enough blood, the brain lives for only three to five minutes. More often the doctors can't fix the damage. Sometimes they are afraid to try something to help because it is dangerous to work on the brain. The doctors might make the person worse if he operates on the brain.
Dr. Robert White, a famous professor and doctor, thinks he knows a way to help. He thinks doctors should make the brain very cold. If it is very cold, the brain can live without blood for 30 minutes. This gives the doctor a longer time to do something for the brain.
Dr. White tried his idea on 13 monkeys. First he taught them to do different jobs, then he operated on them. He made the monkeys' blood go through a machine. The machine cooled the blood. Then the machine sent the blood back to the monkeys' brains. When the brain's temperature was 10°C, Dr. White stopped the blood to the brain. After 30 minutes he turned the blood back on. He warmed the blood again. After their operations the monkeys were like they had been before. They were healthy and busy. Each one could still do the jobs the doctor had taught them.
【小題1】The biggest difficulty in operating on the damaged brain is that _______.
| A．the time is too short for doctors |
| B．the patients are often too nervous |
| C．the damage is extremely hard to fix |
| D．the blood-cooling machine might break down |
| A．taking the blood out of the brain |
| B．trying the operation on monkeys first |
| C．having the blood go through a machine |
| D．lowering the brain' s temperature |
| A．can last as long as 30 minutes |
| B．can keep the brain' s blood warm |
| C．can keep the patient' s brain healthy |
| D．can help monkeys do different jobs |
| A．a(chǎn),b,c,d | B．c,a,b,d | C．c, b, d, a | D．b, c, d, a |
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科目：高中英語 來源： 題型：閱讀理解
When author Nicholas Carr began researching his book on whether the Internet is ruining our minds，he restricted his online access and email.His new book argues the latest technology renders us less capable of deep thinking.Carr found himself so distracted(分心的) that he couldn’t work on the book while staying as connected.After first feeling confused by his sudden lack of online connection，he was able to stay focused on one task for a long period within several weeks.
Reading on the Internet has changed how we use our brains.Facing a lot of texts，video，music and links to other web pages and blogs，our minds have become used to skimming and scanning information.As a result，we have developed sharper skills at making fast decisions，particularly visual ones，Carr wrote.
But now most of us seldom read books or long articles that would help us focus.We are becoming more like librarians—able to find information quickly and see clearly the best nuggets(有價值的資料)．That lack of focus hinders(阻礙) our longterm memory，leading many of us to feel distracted，he wrote.
“What we are losing is a whole other set of mental skills，which require not the shifting of our focus but the maintaining of our focus，” Carr said，adding that for centuries books protected our brains from distraction and focused our minds on one topic at a time.
But with devices such as Apple’s iPad becoming common，Carr predicts books also will change.“New forms of reading always require new forms of writing，” he said.Carr has a suggestion for those who feel web surfing has left them incapable of concentration—slow down，turn off the Internet and practice the skills of contemplation(沉思) and reflection.“It is pretty clear from the brain science that if you don’t exercise particular cognitive skills，you are going to lose them，” he said.“If you are constantly distracted，you are not going to think in the same way that you would think if you paid attention.”
【小題1】What topic is Nicholas Carr’s new book mainly concentrating on?
| A．Whether there is any need for us to surf the Internet. |
| B．How the Internet changes our way of thinking. |
| C．What we should do when we are surfing the Internet. |
| D．Whether our minds are being influenced by the Internet. |
| A．Anxious. | B．Relaxed. |
| C．Concentrated. | D．Puzzled. |
| A．prevents | B．causes |
| C．protects | D．sharpens |
| A．They should read more books besides surfing the Internet. |
| B．They should often slow down their pace of modern living. |
| C．They should often get away from the disturbing of the Internet. |
| D．They should spend more time thinking while surfing the Internet. |
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科目：高中英語 來源： 題型：閱讀理解
Fish species are expected to shrink in size by up to 24% because of global warming, say scientists.
The scientists argue that failure to control greenhouse gas emissions will have a greater effect on marine ecosystems than previously thought. Previous research has suggested that changing ocean temperatures would affect both the distribution and the reproductive abilities of many species of fish. This new work suggests that fish size would also be heavily affected.
The researchers built a model to see how fish would react to lower levels of oxygen in the water. As ocean temperatures increase, so do the body temperatures of fish. But, according to lead author, Dr William Cheung, from the University of British Columbia, the lower level of oxygen in the water is key. Warmer waters could decrease ocean oxygen levels and greatly reduce fish body weight. On the other hand, rising temperatures directly increase the metabolic rate of the fish's body function. This leads to an increase in oxygen demand for normal body activities. So the fish will run out of oxygen for growth at a smaller body size.
The research team also used its model to predict fish movements as a result of warming waters. The group believes that most fish populations will move towards the Earth's poles at a rate of up to 35km per decade. "So in, say, the North Sea," says Dr Cheung," one would expect to see more smaller-body fish from tropical waters in the future."
Taking these factors into consideration, the research team concludes that fish body size will shrink between 14% and 24%, with the largest decreases in the Indian and Atlantic oceans.
When compared with actual observations of fish sizes, the model seems to underestimate what's actually happening in the seas. The researchers looked at two case studies involving North Atlantic cod and haddock. They found that recorded data on these fish showed greater decreases in body size than the models had predicted.
Dr Alan Baudron, from the University of Aberdeen, UK, believes smaller-sized fish could seriously affect the ability of fish to reproduce. "Smaller fish produce fewer and smaller eggs which could affect the reproductive potential of fish stocks," he said.
【小題1】What's the main idea of the passage?
| A．Global warming makes fish smaller. |
| B．Global warming makes fish decrease in numbers. |
| C．Global warming affects the fish distribution. |
| D．Global warming affects the ability of fish to reproduce. |
| A．The rising body temperatures. |
| B．The lower level of oxygen in the water. |
| C．The increasing metabolic rate. |
| D．The normal body activities. |
| A．more big fish will be born in the sea |
| B．fish tend to swim towards the shore |
| C．fish tend to move towards the warm areas |
| D．fish tend to move towards the colder areas |
| A．make an exact prediction of | B．make too low an estimate of |
| C．make too high an estimate of | D．make a careful study of |
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科目：高中英語 來源： 題型：閱讀理解
The art of reading fiction is largely a matter of inferring meanings. To infer means to understand facts which are not directly stated---only suggested. Inference is one of the commonest ways of knowing things: a child holds his knee and cries; this action implies his feeling; an observer infers that the child is hurt. To infer accurately in everyday life requires caution in observing; to infer skillfully in fiction requires caution in reading; both require disciplined imagination.
The short-story reader can expect to find certain basic elements in any story. For example, all stories involve a person or persons, in a particular setting, faced with a demand for a response. The response called for may be a physical action, such as defeating an adversary(對手) or escaping from a danger; or it may be a mental action, such as adjusting to others or within oneself. In either case, the short story is a description in two ways: first, it shows the motives for a given human action; second, it makes a point about the general human situation. Such descriptions, however, rather than being stated directly, usually are implied by the elements of the story.
When the reader of a story understands all the facts and their interrelationships, he is ready to infer the significance of the story as a whole---its comment on the human situation. This comment, or theme, is the seed from which the story grew. It is also the idea by which all the separate elements of the story are governed, while these in turn further shape and modify the theme. In addition to action, character, and setting, these elements include structure, mood, tone, and point of view.
Fiction reading requires an awareness of all the ways in which a story communicates. It also requires attention to detail. What the author provides is a network of points which serve as clues to his meaning. He invites the reader to develop the meaning by inference, actually to create much of the story himself and so make it part of his own experience.
【小題1】According to the author, "infer" means ________ .
| A．knowingfactsbeyondthestatement |
| B．lookingformoreevidencesforthestatement |
| C．findingoutadifferentmeaningfromthestatement |
| D．a(chǎn)ddingsomefactstothestatement |
| A．Readers’guessing. |
| B．Thebasicelementsofthestory. |
| C．Thesettingofthestory. |
| D．Theinterrelationshipsbetweenpeopleinthestory. |
| A．Inferringcanreallyhelpthereaderdevelopimaginationandenrichhimself. |
| B．Inferringcanhelpthereaderwriteastoryofhisown. |
| C．Thereadershouldlookforanexperiencedescribedinthestoryhereads. |
| D．Theexperiencedescribedinthestorywillleaveagreatimpactonitsreader. |
| A．Inferringisanartofwriting. |
| B．Inferringisaneedinfictionwriting. |
| C．Inferringisthebasicskillinreadingfiction. |
| D．Inferringiscommoninreading. |
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科目：高中英語 來源： 題型：閱讀理解
Way back in 1662，John Evelyn，a brilliant Englishman known for his detailed diaries，wrote about disastrous effects of coal-burning on the city of London .In it,he described an infernal scene of smog．a(chǎn)ir filled with “Columns and Clouds of Smoke’’given out by small industries and residences that burned coal for fuel．
I found the description in the 2003 book When Smoke Ran like Water，by epidemiologist(流行病學(xué)家)and environmental advocator(倡導(dǎo)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(轉(zhuǎn)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
【小題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．a(chǎn)dventurous | C．unbelievable | D．a(chǎn)nnoying |
| A．people burned wood for fuel |
| B．a(chǎn) forest fire created a black cloud over the city |
| C．the government ignored the smog |
| D．most people went abouttheirbusine00 |
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科目：高中英語 來源： 題型：閱讀理解
Have you ever wondered why birds sing? Maybe you thought that they were just happy．After all，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(聲稱)as its own．Only he and his family are welcome there．No other families of the same species(物種)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(筑巢) 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 something to do with attracting mates and setting up territories．
【小題1】Some scientists believe that most of the time birds’singing is actually ．
| A．a(chǎn) way of warning | B．a(chǎn)n expression of happiness |
| C．a(chǎn)n expression of anger | D．a(chǎn) way of greeting |
| A．A place where families of other species are not accepted． |
| B．An area which a bird considers to be its own． |
| C．An area for which birds fight against each other． |
| D．A place where a bird may shout at the top of its Voice． |
| A．Because they want to invite more friends |
| B．Because they want to find outsiders around． |
| C．Because their singing helps frighten outsiders away． |
| D．Because their singing helps get rid of their fears． |
| A．By comparing birds with human beings． |
| B．By reporting experiment results． |
| C．By describing birds’ daily fife． |
| D．By telling a bird's story． |
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科目：高中英語 來源： 題型：閱讀理解
Two new studies suggest that modern running shoes could increase the risk of injuries to runners.
One study involved sixty-eight healthy young women and men who ran at least twenty-four kilometers a week. The runners were observed on a treadmill machine (跑步機). Sometimes they wore running shoes. Other times they ran barefoot (赤腳).
Researchers from the JKM Technologies company in Virginia, the University of Virginia and the University of Colorado did the study.
They found that running shoes create more stress that could damage knees, hips and ankle joints than running barefoot. They observed that the effect was even greater than the effect reported earlier for walking in high heels.
The study appeared in the official scientific journal of The American Academy of Physical Medicine.
The other study appeared in the journal Nature. It compared runners in the United States and Kenya. The researchers were from Harvard University in Massachusetts, Moi University in Kenya and the University of Glasgow in Scotland.
They divided the runners into three groups. One group had always run shoeless. Another group had always run with shoes. And the third group had changed to shoeless running.
Runners who wear shoes usually come down heel first. That puts great force on the back of the foot. But the study found that barefoot runners generally land on the front or middle of their foot. That way they ease into their landing and avoid striking their heel.
Harvard’s Daniel Lieberman led the study. He says the way most running shoes are designed may explain why those who wear them land on their heels. The heel of the shoe is bigger and heavier than other parts of the shoe, so it would seem more likely to come down first. Also, the heel generally has thick material under it to soften landings.
But the researchers do not suggest that runners immediately start running barefoot. They say it takes some training. And there can be risks, like running when your feet are too cold to feel if you get injured.
The study was partly supported by Vibram, which makes a kind of footwear that it says is like running barefoot. The findings have gotten a lot of attention. But the researchers say there are many problems in the way the press has reported in their paper. So they have tried to explain their findings on a Harvard Website.
【小題1】What’s the main idea of the passage?
| A．Walking in high heels could cause less serious effects than running barefoot. |
| B．Two new discoveries encourage people to run in high heels. |
| C．Running in shoes is partly good to runners. |
| D．Two new studies prove running without shoes is beneficial to runners in most cases. |
| A．Toes. | B．Hips. | C．Feet. | D．Legs. |
| A．The way that we run by landing on the front or middle of our foot could avoid damaging our heel. |
| B．We should start running barefoot in no time. |
| C．Running in modern running shoes could cause more serious effects than running in high heels. |
| D．We won’t be injured if we run barefoot. |
| A．Persuasive. | B．Negative. | C．Objective. | D．Supportive. |
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科目：高中英語 來源： 題型：閱讀理解
Today, when a fire breaks out, you can be sure a citizen with a cell-phone camera has posted it to Facebook or Twitter, or sent it to the media. But up to now, that citizen has not been able to easily send images and details of what is happening to the people who need it most: police, firefighters and building-security people who must respond, and whose ability to help is often measured in minutes, if not seconds.
That's about to change. A one-year old company called Elerts has developed a system that's designed to mobile and social technologies to speed the flow of information between citizens and emergency workers in time of danger. The system involves free mobile applications—iPhone and iPad app（應(yīng)用軟件）is available now—that eyewitnesses can use to report incidents and get public-safety warnings. And Elerts is offering a management console（控制臺）for security firms and universities to receive the reports and distribute warnings and instructions, like a map with the best evacuation route（疏散路線）.
The service is the brainchild of Chris Russo, deputy fire chief in the coastal town of Hull, Mass. As mobile communications sped up, he grew increasingly frustrated by his inability to communicate effectively with colleagues and the public, particularly with people who are at the scene and might be able to provide help.
"Remembering situations when communications failed puts a pit in my stomach," Mr. Russo says. Last summer, he was in a search at a beach for a missing boy, who went into a bathhouse but didn't come out. First responders feared an abduction （綁架） on the beach or shark attack. The child's mother, who didn't speak English well, was so sad that she couldn't remember what color shorts he had on. Mr. Russo had no photo of the child, and no ability to turn to beachgoers.
Two long hours later, the boy was spotted by a low-flying helicopter lost and alone on the beach crying—a lucky break. "If 5 percent of beachgoers had an app to receive a message and send in sightings of a lost boy, the happy ending might have come much sooner," Mr. Russo said.
【小題1】What is the passage mainly about?
| A．A moving story of Chris Russo． | B．An app for reporting emergency． |
| C．A cell-phone instant service． | D．An app for firm management． |
| A．Makes me feel frustrated． | B．Causes a stomachache． |
| C．Arouses my interest． | D．Leaves a hole in my stomach． |
| A．have to carry out rescue work in minutes |
| B．must send images and details immediately |
| C．need images and detailed information badly |
| D．have to turn to Facebook and Twitter for details |
| A．a(chǎn)dvertise his creativity in communication |
| B．show readers the working principle of the new system |
| C．make the passage more interesting to read |
| D．inform readers how Russo got the idea of the service |
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