题目
题型:不详难度:来源:
By shining a laser beam (激光束) on the tiny pieces of algae floating in the water,the researchers said they hear sound waves that tell them the type and amount of contamination (致污物) in the water.
“It is a red light,telling us that something is beginning to go wrong with the quality of water,” said Zvy Dubinsky,an aquatic biologist at Israel’s Bar Ilan University.“Algae is the first thing to be affected by a change in water quality.”“The secret,” he said,“is to measure the rate of photosynthesis (光合作用) in the algae,meaning the plant’s ability to transform light into energy.” During photosynthesis,plants also release oxygen into the air.
Dubinsky’s technique is easy to perform because of the overabundance of algae in the planet’s water.Most of the oxygen in the atmosphere comes from algae.A prototype tester that occupies about one square meter of a laboratory desktop,shoots a laser beam at water samples to stimulate photosynthesis in the algae.But not all of the laser’s heat is used.Depending on the condition of the algae and the rate of photosynthesis,some of the heat is shot back into the water,creating sound waves,Dubinsky said.With a special underwater microphone,researchers are able to analyze the strength of the sound waves and determine the health of the algae and the condition of the surrounding water.
“Algae suffering from lead poisoning,like waste discharged from battery and paint manufacturing plants,will produce a different sound than those suffering from lack of iron or exposure to other toxins,” said researcher Yulia Pinchasov.She said that testing algae photosynthesis can determine water quality more accurately and easily than laborintensive methods now used like chemical and radioactive carbon testing.
小题1:The underlined word “algae” in Paragraph 2 probably refers to a kind of________.
A.instrument | B.plant |
C.wood | D.pollutant |
A.Because it floats on the water. |
B.Because it can have photosynthesis. |
C.Because it is the first to be polluted. |
D.Because it can produce different sounds. |
A.algae can produce a loud sound when polluted |
B.algae can die easily from pollution |
C.photosynthesis of the algae can only be caused by sunlight |
D.photosynthesis of the algae is related to water quality |
A.Scientists Listen to Plants to Find Water Pollution |
B.A Prototype Tester Is Used to Determine Water Pollution |
C.The Importance of Photosynthesis of the Algae |
D.The Problem of Chemical and Radioactive Carbon Testing |
答案
小题1:B
小题2:C
小题3:D
小题4:A
解析
小题1: B
解析 词义猜测题。由文章第一句中的“what the plants”及第三段倒数第二句中“meaning the plant’s ability to transform light into energy”可推出,algae是一种植物,因为只有植物才能进行光合作用。
小题2: C
解析 细节理解题。由文章第三段第二句可知,藻类是水中最先受到污染的植物,因此科学家用它来研究并判断水的污染情况。
小题3: D
解析 推理判断题。由文章最后一段可知,通过检测藻类的光合作用可以确定水的质量,因此藻类的光合作用跟水的质量有密切关联。
小题4:A
解析 主旨大意题。概括全文可知,本文主要讲了科学家通过探听水中植物的状况来发现水污染的程度。文章第一段就点明了主旨。
核心考点
试题【Scientists in Israel have discovered a new way to test for water pollution by “l】;主要考察你对题材分类等知识点的理解。[详细]
举一反三
There are many sources of indoor air pollution in any home.These include sources such as oil,gas,coal,wood,and tobacco products,building materials,wet or damp carpet,and furniture made of certain pressed wood products,products for household cleaning and maintenance,personal care,or hobbies,central heating and cooling systems.
Immediate effects may show up after a single exposure (暴露) or repeated exposures.These include irritation of the eyes,nose,and throat,headaches,dizziness.Such immediate effects are usually shortterm and treatable.Sometimes the treatment is simply removing the person’s exposure to the source of the pollution,if it can be identified.
The likelihood of immediate reactions to indoor air pollutants depends on several factors.Age and preexisting medical conditions are two important influences.In other cases,whether a person reacts to a pollutant depends on individual sensitivity,which varies tremendously from person to person.Some people can become sensitized to biological pollutants after repeated exposures,and it appears that some people can become sensitized to chemical pollutants as well.
Certain immediate effects are similar to those from colds or other viral (病毒性的) diseases,so it is often difficult to determine if the symptoms are a result of exposure to indoor air pollution.While pollutants commonly found in indoor air are responsible for many harmful effects,there is considerable uncertainty about what concentrations or periods of exposure are necessary to produce specific health problems.People also react very differently to exposure to indoor air pollutants.Therefore,further research is needed to better understand the effects of indoor air pollution and to find efficient ways to protect our health.
小题1:According to the first paragraph,which of the following is NOT true?
A.People often fail to notice indoor air pollution. |
B.Indoor air pollution sometimes is more dangerous than outdoor air pollution. |
C.Outdoor air pollution may not be so serious as indoor air pollution. |
D.It is obvious that people have been paying more attention to indoor air pollution. |
A.Building materials. | B.Wet carpet. |
C.Cooling system. | D.Refrigerators. |
A.Bad intention. | B.Much sensitivity. |
C.Injury. | D.Carelessness. |
A.Reactions of Pollution | B.Danger from Home |
C.Pollution Resources | D.Different Pollutions |
Robotic technology,in particular,holds much promise,McAteer says,especially when it comes to mapping mines and rescuing trapped miners—the special operations of the mining industry.
One of the first mining robots was developed five years ago at CarnegieMellon University’s Robotics Institute.It was called Groundhog and it looked like a golf cart.It used lasers(激光器) to “see” in dark tunnels and map abandoned mines—some of the most dangerous work in the business.
The latest design is called Cave Crawler.It’s a bit smaller than Groundhog,and even more advanced.It can take photos and video and has sensors mounted(增加) that can detect the presence of dangerous gases.Incredibly,the robot has a real sense of logic.If it comes across an obstacle it gets confused.It has to think through the process and where to go next,and sometimes it throws_a_fit just like a real person.
The biggest obstacle,though,is cost.The original research project was federally funded,but that money has dried up,and it’s not clear where future funding will come from. Partly for that reason,and partly because of advances in safety,mining is not nearly as dangerous as it was in the past.Since 1990,fatalities(致命性) have declined by 67 percent and injuries by 51 percent,according to the National Mining Association.
Some experts predict that robots in mines will serve much of the same function that they do in the automotive industry.The robots do the most repetitive and dangerous jobs,but don’t eliminate(消除) the need for human workers.
小题1:The underlined phrase “throws a fit” in Paragraph 4 probably means “________”.
A.gets angry | B.gets sick |
C.becomes hungry | D.becomes cheerful |
A.robots in mines will serve much in the automotive industry |
B.there will be no need for human workers in mines |
C.the mine robots will have a very bright future |
D.robots in mines have a long way to go |
A.Mining robots do most of the mining work at present. |
B.Groundhog can discover the presence of dangerous gases. |
C.Experts are trying to make robots save miners in danger. |
D.Robots cannot do dangerous work in dark areas. |
A.Mining Accidents in America |
B.Could Robots Replace Humans in Mines? |
C.Cave Crawler,the Latest Robot |
D.The Development of Robots |
Two thirds of customers say that environmental considerations inform their purchases to the same degree as they did a year ago,while more than a quarter say that they are now even better aware of the environmental effect on what they buy.
This may help to influence how shops store goods on their shelves.And the companies should still make efforts to become more environmentally friendly.Two out of three people think it is important to buy from environmentally responsible companies,with about one in seven saying that they had even decided to take their custom elsewhere if they felt a company’s environmental reputation was not good enough.
Harry Morrison,chief executive(主管)of the Carbon Trust,sympathizes:“I understand this situation where survival is very important now.But from environmental considerations,the clock is ticking—we don’t have much time.In addition,cutting carbon has an immediate effect as costs drop and a mediumterm benefit for the brand.”
Larger companies have an extra motivation to look at reducing their carbon footprint,as new rules next year will require businesses to buy carbon allowances to make up for their emissions(排放).Those that have taken early action will have a head start.More than two thirds of consumers are not clear about which companies are environmentally responsible.This suggests that firms that are able to relay clearly their message to the public will be in a pole position to attract shoppers.
The Carbon Trust believes that it can help by informing customers about the good work companies are doing.“When companies are granted(授予) the standard,they can use a logo(标识) in all their marketing which makes it clear that they are working towards cutting emissions,” Mr.Morrison said. (2010·福建,C)
小题1:What’s the main idea of the passage?
A.Businesses are finding ways to send their message to the shoppers. |
B.Companies will soon get information about cutting carbon emissions. |
C.Firms are making efforts to encourage customers to keep goods at home. |
D.Firms are urged to cut carbon emissions by shoppers’ environmental awareness. |
A.affect | B.change | C.disturb | D.reject |
A.will benefit from cutting carbon emissions |
B.should buy carbon allowances for shoppers |
C.are required to make up for their carbon emissions |
D.have encouraged shoppers to take their custom elsewhere |
A.have a strong desire to reduce costs |
B.use the same logo in their marketing |
C.gain advantages by taking early action |
D.attract more shoppers by storing goods |
A study of a group of 3,500 people showed that those who scored high for pessimism on a standardized personality test had a 30 percent increased risk of developing dementia 30 to 40 years later.
Those scoring very high on both anxiety and pessimism scales had a 40 percent higher risk,the study showed.
“There appears to be a doseresponse pattern.That is,the higher the scores,the higher the risk of dementia,”Dr Yonas Geda,a neuropsychiatrist at the Mayo Clinic in Rochester,Minnesota who led the study,said in a statement.
Geda and his colleagues looked at the medical records of 3,500 men and women who lived near the clinic between 1962 and 1965.
They all took the Minnesota Multiphasic Personality Inventory,a standard personality and life experience test,Geda’s team told a meeting of the American Academy of Neurology in Miami.
In 2004,the team interviewed the participants or family members.
Those who scored higher for anxiety and pessimism on the test were more likely,as a group,to have developed dementia by 2004,including Alzheimer’s disease and vascular (血管的) dementia.
This did not mean a person who is pessimistic could assume he or she has a higher risk of developing dementia.
“One has to be cautious in interpreting a study like this,”Geda said.
“One cannot make a leap from group level data to the individual.Certainly the last thing you want to do is to say,‘Well,I am a pessimist;thus,I am doomed to develop dementia 20 or 30 years later,’because this may end up becoming a selffulfilling prophecy (预言).”
And there is NOT any specific way to prevent dementia,although many studies have shown that a healthy diet,exercise,keeping active in other ways,doing puzzles and other activities lower the risk.
小题1:What is the passage mainly about?
A.It is impossible for people to avoid dementia. |
B.People who always have negative feelings may have a higher risk of getting dementia. |
C.If we have a healthy diet,we would have no chance of getting dementia. |
D.A person who is pessimistic has a higher risk of developing dementia. |
A.There are many ways to prevent dementia effectively. |
B.A person who is pessimistic is sure to get dementia. |
C.Those who lead a happy life will not get dementia when they are old. |
D.Those who scored high for pessimism might have a higher risk of dementia. |
A.A healthy diet. | B.Proper exercises. |
C.Doing puzzles. | D.Getting up early. |
A.Cheerless. | B.Optimistic. |
C.Unhappy. | D.Upset. |
Compared with Chinese libraries,college libraries in the US and UK tend to offer more resources.A postgraduate at Yale University can borrow as many as 225 books at a time.
In addition to borrowing books,there are online and electronic resources.These include a database search of popular and academic material,such as LexisNexis Academic,which offers items from newspapers and magazines.
Although books and articles are the items that students ask for most frequently,some libraries provide audio and video recordings,maps and sheet music(活页乐谱).At some schools,teachers and tutors put electronic copies of their teaching PPTs on the library web to give easier access for students.
Another useful service in western college libraries is the Interlibrary Loan.This allows a student at one school to borrow books from another school.The loan request is made through the student’s college library,which gets the book,gives it to the user,and arranges for its return.
Technology has brought more services to students and has made libraries attractive.Some universities have services for students to send messages through the computer or mobile texts to ask the library staff for information.
Earlier this year,Harvard University introduced a new Scan and Deliver service,allowing students to make requests for parts of books and articles.Requests made through the system are handled by library staff.The student receives an email with an Internet link to the scanned pages.The service is free and all material comes within four days.
It used to be that libraries didn’t allow food or drinks.But that rule is changing and many of them now contain a café so students can spend as much time as they want in the library.
Actually,some US university libraries are now allnight affairs,or have at least one study room open all night.
小题1:In western college libraries a postgraduate can ________.
A.have a free drink or a meal |
B.borrow as many books as they want |
C.ask questions and get answers from their tutors |
D.access not only books but other study resources |
A.guide | B.library |
C.database | D.university |
A.Books and articles. |
B.Audio and video recordings. |
C.Maps and sheet music. |
D.Tutors’ teaching PPTs. |
A.Chinese library services are better than western ones. |
B.Library staff play an important role in college library service. |
C.Postgraduates can post their own PPTs on the library website. |
D.24hour services are adopted in all western libraries nowadays. |
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