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 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 change 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：文章大意：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)理解題。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)理解題。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)理解題。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)理解題。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
One suicide and three attempted ones that left two seriously injured, all by middle school students in Shanghai last week, cast a gloom (憂郁) over an otherwise happy beginning of a new term there. The terrible things took place even as the Ministry of Education and China Central Television organized the first lesson on TV about personal safety for students last Monday, the first day of the new semester. Such things suggest that this first lesson is more than necessary. Not only should kids be taught how to protect themselves in times of emergency, they should also be made aware of the value of tile2 One student was prevented from killing himself from his school building. He said he just could not accept the fact of not being able to go tip to a higher grade with his classmates, and thus considered life meaningless. Another 12-year-old boy who jumped off a building to his death was said to have been a good student, and no one could say why he chose to end his life. Obviously, their inner worlds were seriously affected. But when they chose to take their own lives, their irresponsible choice was clearly the result of a lack of adequate understanding of the value of life.
The ancient sage Confucius (孔子) stressed that one must protect even one's hair and skin from being hurt. He meant that the sense of responsibility for one's parents was important as far as the value of life was concerned. When we talk about the enthusiasm of making contributions to our motherland, we are referring to values that constitute the nobler part of the meaning of life. The value of life should be far beyond the concern for personal interest.
Undoubtedly, those kids who chose to take their own lives were faced only with their own sadness that they could not overcome. If they had a little concern for their parents, for their parents' expectations of them or for their own potential contributions to this world in the future, they would not have gone that far. Difficulties or sufferings are supposed to help kids develop their sense of responsibility and thus help them better understand the value of life.
Too much attention and care from their parents and grandparents have made most of the only children self-centered. Many think it is natural that they deserve to be taken care of by others in whatever way they want. They expect to have their problems solved by their parents or someone else. With such a false sense, they fail to grasp the tough reality of life. They suffer from the illusion (幻覺) that their life should be nothing but plain sailing, Whenever the illusion is broken, they can hardly gather enough courage to face life as it is. So a hotline is indeed necessary to help those kids who find it hard to accept the tough reality of life. But parents and teachers also need to take lessons from the things. They need to know that life should not always be sugar-coated for kids; they should be made to taste the bitter side too as early as possible.
【小題1】From the passage we know that _________.
| A．four students took their lives in Shanghai last week |
| B．being unable to catch up with other classmates led to the 12-year-old boy killing himself |
| C．the importance of life lies in the sense of responsibility for parents |
| D．parents are supposed to tell the kids the bitter side of life as well as the sweet side |
| A．they are worried that they may fall behind others in studies |
| B．they lack the respect for their parents |
| C．they may be physically healthy, but mentally unhealthy |
| D．their parents expect too much from them |
| A．An irresponsible choice. | B．The value of life. |
| C．Weak-minded generation. | D．The reality of life. |
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科目：高中英語 來源： 題型：閱讀理解
One of our biggest fears nowadays is that our kids might some day get lost in a “sea of technology” rather than experiencing the natural world. Fear-producing TV and computer games are leading to serious disconnect between kids and the great outdoors, which will change the wild places of the world, its creatures and human health for the worse, unless adults get working on child’s play.
Each of us has a place in nature we go sometimes, even if it was torn down. We cannot be the last generation to have that place. At this rate, kids who miss the sense of wonder outdoors will not grow up to be protectors of natural landscapes. “If the decline in park use continues across North America, who will defend parks against encroachment（蠶食）?” asks Richard Louv, author of Last Child in the woods.
Without having a nature experience, kids can turn out just fine, but they are missing out a huge enrichment to their lives. Experts predict modern kids will have poorer health than their parents—and they say a lack of outside play is surely part of it; research suggests that kids do better academically in schools with a nature component and that play in nature fosters（培養(yǎng)）leadership by the smartest, not by the toughest, Even a tiny outdoor experience can create wonder in a child. The three-year-old turning over his first rock realizes be is not alone in the world. A clump of trees on the roadside can be the whole universe in his eyes. We really need to value that more.
Kids are not to blame. They are over-protected and frightened. It is dangerous out there from time to time but repetitive stress from computers is replacing breaking an arm as a childhood rite（儀式）of passage.
Everyone, from developers, to schools and outdoorsy citizens, should help regain for our kids some of the freedom and joy of exploring, taking friendship in fields and woods that strengthen love, respect and need for the landscapes. As parents, we should devote some of our energy to taking our kids into nature. This could yet be our greatest cause.
【小題1】 According to the author, what causes kids’ getting lost in a “sea of technology”?
| A．The wild places of the world |
| B．The kids themselves |
| C．The outdoor activities |
| D．TV and computer games |
| A．a(chǎn) hill | B．a(chǎn) library | C．a(chǎn) bar | D．a(chǎn) classroom |
| A．the fault on the part of their parents |
| B．the natural experience in their growing up |
| C．the result of their own carelessness in play |
| D．the effect of stress from computer |
| A．It leads to children’s escape from school. |
| B．It’s helpful only in a limited way. |
| C．It helps develop children from all sides. |
| D．It increases the chance of getting injured. |
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科目：高中英語 來源： 題型：完型填空
It is nice to know what the weather will be like when we plan a trip. Do you know anything about the history of weather? Don’t look at the sky. Don’t look for old weather reports. Looking at the tree rings is more important. Correct weather reports date back only one century, but some trees can provide an exact record of weather even further back.
It is natural that a tree would grow best in a climate with plenty of sunlight and rainfall. It is also expected that little sunlight or rainfall would reduce the growth of a tree. The change from a favorable to an unfavorable climate can be found out by the reading pattern of rings in a tree trunk. To find out the weather of ten years ago, you can count the rings of a tree trunk from the outside to the inside. If the tenth ring is far from the other rings, then it is certain that plenty of sunny and rainy weather occurred. If the rings are close together, then the climate was bad for the tree.
Studying trees is important not only for the history of weather, but also for the history of man. In an area of New Mexico you can find only sand — no trees or people. However, many centuries ago a large population lived there. They left suddenly. Why?
A scientist studied the pattern of the rings of dead trees that had grown there. He made up his mind that the people had to leave because they had cut down all the trees. Trees were necessary to make fires and buildings. So, after the people destroyed the trees, they had to move.
In this example studying tree rings uncovered an exciting fact about the history of man.
【小題1】We can find out the weather of five years ago by counting the rings of a tree trunk ____.
| A．from the left to the right |
| B．from the right to the left |
| C．from the inside to the outside |
| D．from the outside to the inside |
| A．bad | B．sunny | C．favorable | D．rainy |
| A．why the people had to leave |
| B．where the people had to go |
| C．what the people had to eat |
| D．how the people left |
| A．trees provided an exact record of weather for research |
| B．trees could supply them with fruit and food to live on |
| C．trees could supply them with shades |
| D．trees were materials for fires and buildings |
| A．trees can’t live in the area without population |
| B．that studying trees is important for the history of man and weather. |
| C．what the real relation is between tree rings and the history of man and weather |
| D．the history of man is important for the history of trees |
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科目：高中英語 來源： 題型：閱讀理解
It is widely known that any English conversation begins with The Weather. Such a fixation with the weather finds expression in Dr.Johnson’s famous comment that “When two English meet, their first talk is of weather.” Though Johnson’s observation is as accurate now as it was over two hundred years ago, most commentators fail to come up with a convincing explanation for this English weather-speak.
Bill Bryson, for ezample, concludes that,as the English weather is not at all exciting,the obsession with it can hardly be understood. He argues that”To an outsider,the most striking thing about the English weather is that there is not very much of it.” Simply, the reason is that the unusual and unpredictable weather is almost unknown in the British Isles.
Jeremy Paxman, however, disagrees with Bryson, arguing that the English weather is by nature attractive. Bryson is wrong, he says,because the English preference for the weather has nothing to do with the natural phenomena.”The interest is less in the phenomena themselves, but in uncertainty.” According to him, the weather in England is very changeable and uncertain and it attracts the English as well as the outsider.
Bryson and Paxman stand for common misconceptions about the weather-speak among the English. Both commentators, somehow, are missing the point. The English weather conversation is not really about the weather at all. English weather-speak is a system of signs ,which is developed to help the speakers overcome the natural reserve and actually talk to each other. Everyone knows conversations starting with weather-speak are not requests for weather data. Rather, they are routine greetings,conversation starters or the blank”fillers”, In other words, English weather-speak is a means of social bonding.
【小題1】The author mentions Dr.Johnson’s comment to show that________.
| A．most commentators agree with Dr.Johnson |
| B．Dr.Johnson is famous for his weather observation |
| C．the comment was accurate two hundred years ago |
| D．English conversations usually start with the weather |
| A．A social trend. | B．An emotional state. |
| C．A historical concept. | D．An unknown phenomenon. |
| A．Bill Bryson has little knowledge of the weather |
| B．there is nothing special about the English weather |
| C．the English weather attracts people to the British Isles |
| D．English people talk about the weather for its unccrtainty |
| A．To explain what English weather-speak is about. |
| B．To analyse misconceptions about the English weather. |
| C．To find fault with both Bill Bryson and Jeremy Paxman. |
| D．To convince people that the English weather is changeable. |
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科目：高中英語 來源： 題型：閱讀理解
Air pollution is a leading cause of cancer and classified among top human carcinogens (致癌物質(zhì)), said the International Agency for Research on Cancer (IARC), which is the World Health Organization's (WHO) cancer agency, on Oct 17,2013.“Our task was to evaluate the air everyone breathes rather than focus on specific air pollutants,” the IARC's Dana Loomis said in a statement. “The results from the reviewed studies point in the same direction the risk of developing lung cancer is significantly increased in people exposed to air pollution.”
In 2010, lung cancer resulting from air pollution killed 223,000 people worldwide, and there was also convincing evidence that it increases the risk of bladder (膀胱) cancer. Loomis said people in Asia, Eastern North America, some places in Central America and Mexico, as well as North Africa have relatively high exposure(暴露). Developing countries with large populations and booming manufacturing sectors, such as China, are particularly at risk. This week, Harbin, the capital city of Heilongjiang province, became the first Chinese city to officially suspend classes due to serious smog, really good for teachers and students.
Many developed countries face similar problems, although to a lesser（較少的、次要的） degree than most developing nations. Between 91 and 96 percent of Europeans living in cities are exposed to levels of PM2.5—tiny particles with a diameter of less than 2.5 micrometers—that are higher than the WHO safety limits.
Although both the composition and levels of air pollution can vary dramatically from one location to the other, the IARC said its conclusions apply to all areas of the world. “Given the scale of the exposure affecting people worldwide, this report should send a strong signal to the international community to take action without further delay,” said Christopher Wild, director of the IARC.
【小題1】What’s the main task of IARC?
| A．To focus on cancer-causing substances. |
| B．To evaluate the air quality. |
| C．To study the developing risk of cancer. |
| D．To send signals to the international community. |
| A．a(chǎn)ccelerate | B．a(chǎn)cknowledge |
| C．delay | D．decline |
| A．A large number of people worldwide are exposed to air pollution. |
| B．More and more people in developing countries are exposed to air pollution. |
| C．Developed countries face air pollution, the level of which is higher than the safety limits. |
| D．The composition and levels of air pollution vary from place to place. |
| A．PM2.5，bad effect. |
| B．Safety limits of air pollution. |
| C．Signals of air pollution. |
| D．Air pollution, cancer risk. |
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科目：高中英語 來源： 題型：閱讀理解
Last night’s meteor(流星) shower left many people in the community dissatisfied and demanding answers. According to Gabe Rothsclild, Emerald Valley’s mayor, people gathered in the suburbs of the city, carrying heavy telescopes, expecting to watch the brightly burning meteors passing through the sky. What they found instead was a sky so brightened by the city’s lights that it darkened the light of the meteors passing overhead.
“My family was so frustrated,” admitted town resident Duane Cosby, “We wanted to make this an unforgettable family outing, but it turned out to be a huge disappointments.”
Astronomers---scientists who study stars and planets----have been complaining about this problem for decades.They say that light pollution prevents them from seeing objects in the sky that they could see quite easily in the past. They call on people and the government to take measures to fight against it.
There is yet a population besides professional and amateur star observers that suffers even more from light pollution. This population consists of birds,bats frogs,snakes,etc. For example,outdoor lighting severely affects migrating(遷徙的)birds. According to the International Dark-Sky Association. “100 million birds a year throughout North America die in crashes with lighted buildings and towers.”
Countless more animals casualties(傷亡）result from the use of artificial lighting. Clearly, people enjoy the benefits of lighting their evenings,but some scientists think it can be harmful for humans,too. They worry that exposure to light while sleeping can increase person’s chances of getting cancer.
Emerald Valley is only one community that is becoming aware of the negative effects of hight pollution. For years, Flagstaff,Arizona, has enforced lighting regulations in its city in order to help astronomers at the Lowell Observatory. Similar efforts have been made worldwide, and a movement is underway to remind us to turn off lights when we are not using them, so that other creatures can share the night.
【小題1】It happened last night that __________ .
| A．the city light show attracted many people |
| B．the meteors flew past before being noticed |
| C．the city’s lights affected the meteor watching |
| D．the meteor watching ended up a social outing |
| A．Light pollution has remained unsolved for years |
| B．Their observation equipment is in poor repair |
| C．Meteor showers occur less often than before |
| D．Their eyesight is failing due to artificial lighting |
| A．Birds may take other migration paths |
| B．Animal’living habits may change suddenly |
| C．Varieties of animals will become sharply reduced |
| D．Animals’survival is threatened by outdoor lighting |
| A．Lessen the chance of getting cancer |
| B．ensure citizens a good sleep at night |
| C．create an ideal observation condition |
| D．enable all creatures to live in harmony |
| A．Saving wildlife is saving ourselves |
| B．Human activities should be environmentally friendly |
| C．Great efforts should be made to save energy |
| D．New equipment should be introduced for space study |
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科目：高中英語 來源： 題型：閱讀理解
When women sit together to watch a movie on TV, they usually talk simultaneously(同時地) about a variety of subjects, including children, men, careers and what’s happening in their lives. When groups of men and women watch a movie together, the men usually end up telling the women to shut up. Men can either talk or watch the screen—they can’t do both—and they don’t understand that women can. Besides, women consider that the point of all getting together is to have a good time and develop relationships—not just to sit there like couch potatoes staring at the screen.
During the ad breaks, a man often asks a woman to explain the plot and tell him where the relationship between the characters is going. He is unable, unlike women, to read the subtle body language signals that reveal how the characters are feeling emotionally. Since women originally spent their days with the other women and children in the group, they developed the ability to communicate successfully in order to maintain relationships. For a woman, speech continues to have such a clear purpose: to build relationships and make friends. For men, to talk is to relate the facts.
Men see the telephone as a communication tool for sending facts and information to other people, but a woman sees it as a means of bonding（連接). A woman can spend two weeks on vacation with her girlfriend and, when she returns home, telephone the same girlfriend and talk for another two hours.
There is no convincing evidence that social conditioning, the fact that girls’ mothers talked to them more, is the reason why girls talk more than boys. Psychiatrist Dr Michael Lewis, author of Social Behaviour and Language Acquisition, conducted experiments that found mothers talked to, and looked at, baby girls more often than baby boys. Scientific evidence shows parents respond to the brains of their children. Since a girl’s brain is better organized to send and receive speech, we therefore talk to them more. Consequently, mothers who try to talk to their sons are usually disappointed to receive only short grunts(哼哼聲） in reply.
【小題1】While watching TV with others, women usually talk a lot because they .
| A．a(chǎn)re afraid of awkward silence with their families and friends |
| B．can both talk and watch the screen at the same time |
| C．think they can have a good time and develop relationships |
| D．have to explain the plot and body language to their husbands |
| A．experience the happy time again |
| B．keep a close tie with her |
| C．recommend her a new scenic spot |
| D．remind her of something forgotten |
| A．Women’s brains are better organized for language and communication. |
| B．Women love to talk because they are more sociable than men. |
| C．Men do not like talking because they rely more on facts. |
| D．Social conditioning is not the reason why women love talking. |
| A．Women are Socially Trained to Talk |
| B．Talking Maintains Relationships |
| C．Women Love to Talk |
| D．Men Talk Differently from Women |
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科目：高中英語 來源： 題型：閱讀理解
The sound of a mosquito can mean trouble in many parts of the world. The bite of the mosquito can be deadly. The insects carry serious diseases like malaria. It is estimated that almost 630,000 people died from malaria and malaria-related causes in 2012, and most of these cases were in African countries.
In the United States, a group of California scientists is working to develop a more effective and less costly substance(物質(zhì))to protect people from mosquitoes. The researchers are investigating the sense of smell in mosquitoes. They found the insects use the same receptor(感受器)for identifying carbon dioxide in human breath as they do for the smell of our skin. Anandasankar Ray, who is leading the investigation, says scientists tested more than a million chemical compounds(化合物)until they found a substance called Ethyl pyruvate. He says Ethyl pyruvate makes the mosquitoes' receptor inactive. ”When we apply Ethyl pyruvate to a human arm and offer it to hungry mosquitoes in a cage, very few of the mosquitoes are attracted to the human arm because only a few of them are able to smell it out,” said Ray.
Genevieve Tauxe, a member of the research team, says it was not easy to find the neurons (神經(jīng)元)of nose cells that recognise both the smell of human breath and skin. "With the device used to examine mosquitoes, we are able to insert a very small electrode(電極)into the part of the mosquitoes' nose, where its smelling neurons are and where the smell is happening," said Tauxe.
Anandasankar Ray says a product based on Ethyl pyruvate may cost less to produce than DEFT，the most effective chemical treatment now in use. He says DEFT is too costly for most people who live in areas affected by malaria.
“Perhaps by finding smells that can attack other target receptors, we will be able to improve upon DEFT and finally have the next generation of insect behavior control products," said Ray.
【小題1】The best title for the passage is most probably _______________________________.
| A．Scientists Find New Substance to Fight Mosquitoes |
| B．A New Generation of DEET Has Been Developed to Kill Mosquitoes |
| C．Malaria一a Serious Disease Causing 630,000 Deaths |
| D．Ethyl Pyruvate一an Insect Behavior Control Product |
| A．kill the mosquitoes' smelling neurons |
| B．cause the mosquitoes to lose their sense of smell |
| C．result in the inactiveness of the mosquitoes' receptor |
| D．make the mosquitoes uninterested in human breath and skin smell |
| A．inform readers of the new development in fighting mosquitoes |
| B．praise the achievements made in the battle against malaria |
| C．introduce a cheaper product in fighting mosquitoes |
| D．tell the differences between Ethyl Pyruvate and DEET |
| A．the column of newspaper ads |
| B．the health column of a magazine |
| C．a(chǎn) textbook of medical schools |
| D．a(chǎn) collection of doctors' essays |
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