Polar bears are not the only species in danger from global warming, a new report has warned. The US Center for Biological Diversity (CBD)claims 16 Arctic(北极的)animals are at risk from the melting ice as well as the polar bears.The animals have become a symbol of the environmental movement, as their numbers go down with the melting ice caps.
But they are not the only ones.A new report has warned that other animals are in danger of going extinct as well.Sea ice in the Arctic fell to its lowest level after records began in 2007 and scientists predict the area could be largely ice free in summer within 10 years.
Shaye Wolf, the lead author of the report, said Arctic foxes, whales, musk oxen(麝牛), walruses(海象)and four species of seals were all in danger—as well as polar bears.
“The polar bear is the best-known victim(受害者)of rapid melting in the Arctic, but if we don’t reduce greenhouse pollution, many more creatures will follow it down the path to extinction，” she said. “Some Arctic species have already experienced widespread die-offs and population becomes less after losing key habitats and food sources; others face extreme weather events or suffer new pressures from predators(食肉动物).”
The CBD is also afraid these animals could be in danger if mining for oil goes ahead in this area.It is estimated that eight of the world’s 19 polar bear populations are becoming less as they struggle to raise young and hunt for food on ice.
1. What’s the main idea of the passage?| A．Polar bears are the only species in danger from global warming. |
| B．Why all Arctic species are in danger of dying out. |
| C．We should take measures to protect Arctic animals. |
| D．Arctic foxes, whales, musk oxen, walruses and four species of seals were all in danger—as well as polar bears. |
| A．繁衍 | B．灭绝 |
| C．存在 | D．兴衰 |
| A．Nine of the world’s 19 polar bear populations are becoming less now. |
| B．Polar bears are in danger mainly because their food sources are disappearing. |
| C．If we don’t take any effective measures to protect these animals in Arctic, more and more creatures will die out in the future. |
| D．Sea ice in the Arctic fell to its lowest level before records began in 2007. |
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【推荐1】Johannes Fritz, an Austrian biologist, needed to come up with a plan again if he was going to prevent his rare and beloved birds from going extinct.
To survive the European winter, the northern bald ibis needs to migrate south for the winter over the Alps. But shifting climate patterns have delayed when the birds begin to migrate and they are now reaching the mountains too late to make it over the peaks, locking them in an icy death trap. Determined to save them, he decided to teach the birds a new, safer migration route by guiding them himself in a tiny aircraft. He was confident that he could succeed in this daring, unconventional plan.
Some 400 years ago, the Europeans hunted these birds without stopping and devoured the last in the wild, causing the birds to disappear entirely from the wild. When Mr. Fritz was born 56 years ago, the northern bald ibis could be found in Europe only in captivity (圈养).
Mr.Fritz has spent his career reintroducing the birds into the wild. Through years of trial and error, he learned to fly like a bird. He modified (改装) a lightweight aircraft so it would fly at speeds slow enough for the birds to keep up. In 2004, he led the first flock from Austria to Italy, and has since led more migrations. But the route he originally taught the ibises does not work successfully. With climate change warming the area where the birds summer, they now start their migration at the end of October instead of the end of September. The trip is expected to take about six weeks, “Still, we’re optimistic that it’ll work,” said Mr. Fritz.
His family and colleagues witnessed the risks he was taking. “But the unavoidable risks are necessary,” Mr. Fritz said. “It’s not so much a job, but my life’s purpose.”
1. What was Johannes Fritz’s plan?| A．To shorten bald ibises’ migration route. |
| B．To lead bald ibises to migrate on a new route. |
| C．To better the climate patterns for bald ibises. |
| D．To find out a safer destination for bald ibises. |
| A．Destroyed. | B．Abused. | C．Released. | D．Raised. |
| A．Owing to the long time it consumes. |
| B．For the slow speed of his modified aircraft. |
| C．Because of the toughness along the first route. |
| D．Due to higher temperatures in the summer habitat. |
| A．Honest. | B．Innovative. | C．Straightforward. | D．Demanding. |
【推荐2】Paris goes car free on September 19, 2021 as part of an event called “Joumee Paris Respire" or “Paris Breathes Day". For one day only, cars are banned from Paris. Parisians and tourists are invited to udiscover Paris in a new light".
Crowds of Parisians and tourists strolled along the Champs-Elysees avenue on Sunday as a car-free day removed most of the traffic from the French capitals usually busy streets. Pedestrians wandering along the most famous street in Paris could view the Arc de Triomphe in its temporary appearance as an ait installation. The monument has been covered in silvery wrapping, as designed by the late artist Christo.
In 2015, Paris authorities organized its first car-free day in a central zone： Paris without car, expanding the initiative in 2017 to other districts within the city limits. Paris Mayor Anne Hidalgo has sought to use the annual event to curb vehicle use and reduce air pollution.
This new and 7th edition, renamed “Joumee Paris Respire" or “Paris Breathes Day” , takes place on Sunday September 19, 2021!
For 7 hours, from 11 a.m. to 6 p.m. cars are banned from Paris ( excluding rings) , letting bicycles, rollerblades, skateboards, and pedestrians along with public transit users enjoy the city. The persons who are against the regulation might be fined €135. But emergency vehicles, ambulances, buses, cabs and private hire are authorized to drive at 30km/h （ 18. 64 mph） in the Paris Respire areas.
With this action, Paris will take the time to live without the unstopping noise of cars and to show the impacts of the traffic. According to AirParif controling the air quality, the rates of nitrogen dioxide are decreasing on these Car-free days, in comparison with the other Sundays over the year. About 7% less pollutant concentration in the air in Paris are noticed.
Rest assured, there are exemptions （豁免）if you need to go to the hospital in Paris or if you are back from a weekend getaway, but you will have to prove your credentials （证明书）and a proof of address, and respect a limit of 30km/h.
Discovering a car-free Paris, enjoying calm streets and walking the usually-car-blocked streets promises some nice moments, right?
1. What does the underlined word "curb" in Paragraph 3 mean?| A．Allow. | B．Criticize. | C．Promote. | D．Limit. |
| A．Doubtful. | B．Indifferent. | C．Supportive. | D．Negative. |
| A．Every car isn't banned from Paris on this day. |
| B．The air quality of Paris has been improved permanently due to it. |
| C．The car-free day allows tourists to experience the busy street of Paris. |
| D．People can drive in Paris freely as long as they need to go to the hospital. |
| A．Paris goes car free for a day again. |
| B．Paris included the entire city into Paris Breathes Day. |
| C．Crowds flooded into Champs-Elysees during Paris car-free day. |
| D．Essential journeys could still use the streets on the car-free day. |
【推荐3】The UK government has promised to cut the country's greenhouse gas emissions（排放）by at least 68% by 2030 compared with 1990 levels, marking a significant increase from its current goal.
The new goal comes nine days ahead of the UK hosting a “climate action summit（峰会）” to encourage other countries to declare tougher climate plans, known as Nationally Determined Contributions（NDCs）, under the Paris Agreement. Current NDCs will raise temperatures by 3℃. And stronger plans are needed to meet the Paris deal's goal of limiting global warming to 1.5℃.
“This is the most significant NDCs announcement so far from any major economy,” said Richard Black at the Energy and Climate Intelligence Unit, a UK-based think tank, in a statement.
The new goal is exactly in line with what the government's official climate adviser, the Climate Change Committee, called for in a letter published earlier today. The group said 68% would be “world-leading” compared with existing plans of governments.
The UK had previously promised a 53% cut in emissions as part of a joint（共同的）effort with the rest of the European Union, but the UK is determined to produce a new NDCs. Separately, the UK had also promised a 57% cut by 2032 domestically.
It is clear that far more action will be needed if the UK is to meet the new goal. The government's own analysis last week showed that recent major methods, such as banning new oil-fueled car sales by 2030, had failed to do enough to put the UK on track even for the old goal of 57% by 2032. The new goal obviously widens that gap further.
1. Why did the UK declare its new goal before "climate action summit”?| A．To show its former plans are based on facts. |
| B．To blame other countries for their low goals. |
| C．To call on other countries to take bigger steps. |
| D．To take the lead in controlling greenhouse gas emissions. |
| A．15%. | B．68%. | C．57%. | D．53%. |
| A．Opposed. | B．Subjective. |
| C．Indifferent. | D．Doubtful. |
| A．A new goal will be put forward on “climate action summit”. |
| B．UK came up with a common goal under the Paris Agreement. |
| C．UK's recent major policies are far from its pre-determined goal. |
| D．UK sets an ambitious climate goal of 68% emissions cut by 2030. |
【推荐1】Scientists say they have found high levels of small plastic particles(颗粒) in Arctic snow. A German-Swiss research team collected snow samples(样本）from the Arctic and other areas. They included northern Germany, the Bavarian and Swiss Alps, and the North Sea island of Heligoland.When the researchers examined the samples in a laboratory, they were surprised to find very high levels of microplastics.
Microplastics are very small pieces of plastic. These plastic particles are generally smaller than 5 millimeters in length. They come from the breakdown of man-made plastic products and industrial waste.
The study found the highest levels of microplastics came from the Bavarian Alps. One snow sample from the area had 154,000 microplastic particles per liter. Samples collected from the Arctic had much lower levels. However, even samples from the Arctic contained up to 14,000 particles per liter.
The study also attempted to explore how some of the material could have been carried in the atmosphere. A limited number of earlier studies did find microplastics in the air of some cities, including Paris, Tehran and Dongguan, China.
Bergmann Melanie co-wrote the report on the new study. She believes the new study clearly shows that “the majority of the microplastic in the snow comes from the air.” The new study suggests that much of the microplastic found in Europe and the Arctic comes from the atmosphere and snow.
While there is growing concern about the effect of microplastics on the environment, scientists are still studying their possible harmful effects on humans and animals. “I hope the new study will lead to more research on this issue. I think microscopic plastic particles should be included in worldwide observations of air pollution levels.We really need to know what effects microplastics have on humans, especially if inhaled with the air that we breathe.” Bergmann said.
1. Why did scientists collect samples from so many places in paragragh 1?| A．To make the research convincing. |
| B．To attract people to explore there. |
| C．To measure the length of microplastics . |
| D．To examine the samples easily in the lab. |
| A．The risks of microplastics. |
| B．The transport of microplastics. |
| C．The breakdown of plastic products. |
| D．The description of microplastics. |
| A．Many people threw them away at the Alps. |
| B．They were delivered to remote areas through air. |
| C．They could be caught sight of in the air. |
| D．They had no great effect on the environment. |
| A．Scientists are worried about the the influence of microplastics. |
| B．We have found a practical solution to the environment problem. |
| C．The effect of microplastics on human must be urgently researched. |
| D．There is no need to change observations of air pollution levels. |
【推荐2】Cathy Winston is a sports nutritionist. Among her regulars are athletes. Cathy thrives on the variety, with each new sport providing new challenges and a renewed appreciation of her chosen field of expertise. In her view, dealing with athletes from various sport backgrounds helps her become seasoned, which is a key part of being a successful nutritionist. “You have to understand nutrition and people, and then you can begin to work in this field,” she says. “Besides, in tennis you must learn to be reactive, because you don’t know how long the match lasts. However, it’s 90 minutes in football. So you know what you’re fueling for.”
Regardless of the sport, Cathy’s attitude remains the same any athlete failing to respect nutrition is one who is failing to fulfill their potential. It’s a key part of the training process. It’s not just something that you take casually. She advises her athletes to hold nutrition in the same regard as they do their most crucial bit of equipment. “Just as you wouldn’t forget to put your shin pads(护腿板)or your boots in your kit bag, don’t forget to put in your drinks and your snacks. That informs how well you train, because you can’t get out if you haven’t put in.”
Nutritionists are sometimes unfairly represented as militant(斗志昂扬的)types telling what athletes can and can’t eat. But Cathy insists that when to eat is more important than what. “It’s about when’s the right time to have it in,” she says. It’s a message that Cathy says can take a while to sink in. “A lot of boxers say, ‘but bananas make you fat, right?’, and there’s this inherent belief that we mustn’t eat those kinds of things. But it’s not about what to cut out. It’s about making sure that you’ve got the foundation right for health and performance. It’s that one size fits one. It’s what works for you. To be an excellent athlete, you really need to be an exceptional eater.”
1. What does Cathy think about her job?| A．It highly values experience and flexibility. |
| B．It mainly focuses on the duration of matches. |
| C．It merely needs to understand nutrition and people. |
| D．It hardly faces new challenges in every competition. |
| A．By telling a story. | B．By making a comparison. |
| C．By providing data. | D．By analyzing a phenomenon. |
| A．Focusing on the timing of the diet. | B．Increasing the variety of foods. |
| C．Following a strict and militant diet plan. | D．Cutting out specific foods from the diet. |
| A．A good eater is a great athlete. |
| B．Nutritionists act as unsung heroes behind athletes. |
| C．Nutrition determines the results in the competition. |
| D．Food is less important than skills in the sports field. |
【推荐3】Many people treat “life” as something that happens to them. They think they are the victims.
Choose your friends carefully. As they say, “
When you go your own way, everyone will tell you that you’re wrong at first. But when they find actually they are wrong, they will all come back around.
In order to get to where you know you can go, you have to say “no” a hundred times more than you say the word “yes”.
| A．Everybody sets goals. |
| B．They create the life they want to live. |
| C．Some people just don’t know when to quit. |
| D．They will see the life you’ve built for yourself. |
| E．You must be faithful to yourself and your goal. |
| F．When things go wrong, they think it’s someone else’s fault. |
| G．You are a reflection of those who you spend the most time with. |
【推荐1】“Old wives’ tales” are beliefs passed down from one generation to another. For example,most of us remember our parents’ telling us to eat more of certain foods or not to do certain things. Is there any truth in these teachings? Some of them agree with present medical thinking,but others have not passed the test of time.
Did your mother ever tell you to eat your carrots because they are good for your eyes? Scientists now report that eating carrots can help prevent a serious eye disease called macular degeneration. Eating just one carrot a day can reduce the possibility of getting this disease by 40%. Garlic is good for you,too. It can kill the type of virus that causes colds.
Unfortunately, not all of Mom’s advice passed the test of medical studies. For example, generations of children have been told not to go swimming within an hour after eating. But research suggests that there is no danger in doing so. Do sweets cause tooth problems?Well, yes and no. Sticky sweets made with grains(谷物) tend to cause more problems than sweets made with simple sugars.
Even though science can tell us that some of our traditional beliefs don’t hold_water,_there is still a lot of truth in the old wives’ tales. After all, much of this knowledge has been accumulated (积累) from thousands of years of experience in family health care. We should respect this body of knowledge even as we search for clear scientific support to prove it true or false.
1. Which of the following is TRUE according to the text?| A．Sticky sweets are damaging to our teeth. |
| B．Eating garlic is good for our eyes. |
| C．Swimming after a meal is dangerous. |
| D．Carrots prevent people from catching colds. |
| A．by cause and effect |
| B．by order in space |
| C．by examples |
| D．by order in time |
| A．to be valuable |
| B．to be believable |
| C．to be admirable |
| D．to be suitable |
| A．Subjective(主观的). |
| B．Objective(客观的). |
| C．Dissatisfied. |
| D．Curious. |
【推荐2】People who play drums regularly for years differ from unmusical people in their brain structure and function. The results of a study by researchers from Bochum suggest that they have fewer, but thicker fibers in the main connecting tract between the brain hemispheres(半球). In addition, their motor brain areas are organized more efficiently. This is the conclusion drawn by a research team headed by Dr. Lara. It was published in the journal Brain and Behavior, online on 4 December 2019.
The researchers were interested in drummers because their movement control far surpasses that of untrained people. "Most people can only perform fine motor tasks with one hand and have problems playing different rhythms with both hands at the same time," explains Lara, "Drummers can do things that are impossible for untrained people."
The team intended to gain new insights into the organization of complex motor processes in the brain by identifying the changes in the brain caused by this training. The researchers tested 20 professional drummers who have played their instrument for an average of 17 years and currently practice for more than ten hours per week. They examined them using various MRI imaging techniques that provide insights into the structure and function of the brain. They then compared the data with measurements of 24 unmusical control subjects. Both groups had to play drums to test their abilities and were then examined in the MRI scanner.
Drummers presented clear differences in the front part of the corpus callosum(胼胝体)responsible for motor planning. The data indicated that the drummers had fewer but thicker fibers in this important connecting tract. This allows musicians to exchange information between the hemispheres more quickly than the controls.
Although drummers might be good at motor coordination, they are less active in motor tasks than that of control subjects. This phenomenon indicates that a more efficient brain organization in the areas leads to less activation in professionals.
1. Which has the closest meaning with the underlined word in Paragraph 2?| A．Correspond with. | B．Go beyond | C．Differ from. | D．Fall behind. |
| A．By analyzing previous study. |
| B．By organizing complex motor tasks. |
| C．By testing their abilities and scanning the brains. |
| D．By comparing amateur drummers and unmusical people. |
| A．They are more active in motor tasks. |
| B．They can play rhythms more quickly. |
| C．They have better imagination and insights. |
| D．They have more efficient brain organization. |
| A．Playing drums changes the brain. |
| B．Playing drums can be trained. |
| C．Playing music makes you active. |
| D．Playing music brings benefits. |
【推荐3】Years ago when I was at the Grand Canyon, I remember someone coming up to the canyon's edge, taking a shot with their camera and then walking away, like ‘got it- done’, barely even glancing at the magnificent scene sprawling in front of them,” Linda Henkel, a scientist at Fairfield University, US told Live Science.
Henkel was surprised by how obsessed people are with taking pictures these days—before dinner, during friends' birthday parties, on museum tours and so on. You know people just like that, don’t you?
They keep taking pictures because they think that it helps record the moment, but as Henkel's latest study has just found out, this obsession may prevent their brains from remembering what actually happened, reported the Guardian.
In her study, Henkel led a group of college students around a museum and asked them to simply observe 15 objects and to photograph 15 others. The next day the students' memory of the tour was tested, and the results showed that they were less accurate in recognizing the objects and they remembered fewer details about them if they photographed them.
“When people rely on technology to remember for them—counting on the camera to record the event and thus not needing to attend to it fully themselves, it can have a negative impact on how well they remember their experiences,” Henkel explained.
But there is also an exception: if students zoomed in to photograph part of an object, their memory actually improved, and those who focused the lens on a specific area could even recall parts that weren’t in the frame.
So basically, this study is saying that constantly taking pictures can harm your memory. But shouldn't reviewing pictures we have taken help wake up our memories? This is true, but only if we spend enough time doing it.
“In order to remember, we have to access and interact with the photos, rather than just collecting them,” Henkel told The Telegraph. However, previous research has shown that most people never take the time to look over their digital pictures simply because there are too many of them and they aren't usually very organized on their computers.
1. The author mentioned Henkel's trip to the Grand Canyon at the beginning to _______.| A．describe the great view of the Grand Canyon. |
| B．complain about some tourists bad habits. |
| C．point out people’s obsession with taking pictures. |
| D．give suggestions on how to enjoy one’s tour. |
| A．Taking pictures in a museum tour helps students recognize objects better. |
| B．Reviewing pictures always helps people bring back memories. |
| C．Pictures that focus on the details of objects are likely to improve people’s memories. |
| D．People should spend more time taking pictures than studying real objects. |
| A．People who tend to use cameras to catch the moment will remember the experience. |
| B．People should collect many pictures to remember the experience. |
| C．Taking pictures have negative impact on remembering the experience. |
| D．Reviewing pictures constantly can help remembering the experience. |
| A．Some skills to learn for taking pictures. |
| B．People's obsession with taking pictures and its influence. |
| C．How pictures remind us of our past. |
| D．How to deal with pictures after taking trips. |
【推荐1】People speak English in different parts of the world. The same words can be used in different ways, depending on where you live. People can also have completely different ways of saying the same thing.
The Oxford English Dictionary (OED) is asking the public to help it add new words. Editors want to find the regional differences in English around the world. They want to expand its record of the language.
Last year, the OED, BBC Radio and the Forward Arts Foundation teamed up to find local words in the United Kingdom. It resulted in more than 100 regional words and phrases being added to the dictionary. One was “cuddy wifter”, which means a left-handed person.
Now, the OED is widening its search to English speakers around the world. Eleanor Maier, an editor at OED, said the response has been great. Editors are listing a bunch of suggestions to include in the dictionary.
These include Hawaii’s “hammajang”, which means “in a disorderly state”. Another is the word for a swimming costume, “dookers” or “duckers”. It is used in Scotland.
The OED also might include the word “frog-drowner”, which Americans might use to describe a downpour of rain. Another possibility is “brick”. It means “very cold” to people in New Jersey and New York City.
The dictionary has already found that, depending on location, a picture hanging off center might be described as “agley”. It might also be called “catawampous” or “ahoo”.
“The OED aims to cover all types of English,” Maier said. That includes scientific words, slang and regional language. Maier also said that it can be difficult for the OED’s editors to identify regional words. The terms are more often spoken than written down.
The appeal is called Words Where You Are. It is looking for more suggestions. “We were surprised and pleased by the number of regional words we were able to include,” said Maier.
1. Which local word of the following most likely comes from one region of the United Kingdom?| A．Hammajang. | B．Dookers. |
| C．Catawampous. | D．Frog-drowner. |
| A．It is challenging to create a complete collection of regional words. |
| B．People are not enthusiastic about the appeal for regional words. |
| C．Regional words are more used orally than in written form. |
| D．Understanding regional words can be helpful when communicating. |
| A．It’s time to track where the local words come from. |
| B．The same English words can be used to say different things. |
| C．OED aims to expand its collection to attract locals. |
| D．OED will include more regional words from around the globe. |
| A．Entertainment. | B．Sports. |
| C．Culture. | D．Health. |
【推荐2】 We have encountered a crisis around the corner. You mean global warming? The world economy? No, the decline of reading. People are just not doing it anymore, especially the young. Who’s responsible?
Actually, it’s more like, what is responsible? The Internet, of course, and everything that comes with it – Facebook, Twitter . You can write your own list.
There’s been a warning about the imminent death of literate civilization for a long time. In the 20th century, first it was the movies, then radio, then television that seemed to spell doom for the written world. None did. Reading survived; in fact it not only survived, it has flourished. The world is more literate than ever before – there are more and more readers, and more and more books.
The fact that we often get our reading material online today is not something we should worry over. The electronic and digital revolution of the last two decades has arguably shown the way forward for reading and for writing. Take the arrival of e-book readers as an example.
Devices like Kindle make reading more convenient and are a lot more environmentally friendly than the traditional paper book.
As technology makes new ways of writing possible, new ways of reading are possible. Interconnectivity allows for the possibility of a reading experience that was barely imaginable before. Where traditional books had to make do with photographs and illustrations, an e-book can provide readers with an unlimited number of links: to texts, pictures, and videos. In the future, the way people write novels, history, and philosophy will resemble nothing seen in the past.
On the other hand, there is the danger of trivialization. One Twitter group is offering its followers single-sentence-long “digests” of the great novels. War and Peace in a sentence? You must be joking. We should fear the fragmentation of reading. There is the danger that the high-speed connectivity of the Internet will reduce our attention span—that we will be incapable of reading anything of length or which requires deep concentration.
In such a fast-changing world, in which reality seems to be remade each day, we need the ability to focus and understand what is happening to us. This has always been the function of literature and we should be careful not to let it disappear. Our society needs to be able to imagine the possibility of someone utterly in tune with modern technology but able to make sense of a dynamic, confusing world.
In the 15th century, Johannes Guttenberg’s invention of the printing press in Europe had a huge impact on civilization. Once upon a time the physical book was a challenging thing. We should remember this before we assume that technology is out to destroy traditional culture.
1. The following are all cited as advantages of e-books EXCEPT _____.| A．multimodal content | B．environmental friendliness |
| C．convenience for readers | D．imaginative design |
| A．Ironic | B．Worried. |
| C．Impersonal | D．Doubtful. |
| A．good judgment | B．high sensitivity |
| C．good imagination | D．the ability to focus |
| A．Technology pushes the way forward for reading and writing. |
| B．Interconnectivity is a feature of new reading experience. |
| C．Technology is an opportunity and a challenge for traditional reading. |
| D．Technology offers a greater variety of reading practice. |
【推荐3】If you live in a desert, maintaining a supply of fresh water is a challenge. One answer is desalination, but that needs a source from which to get the salt away—which in turn requires that your desert be near the sea. The other is related to moisture. Even in inland deserts, though, moisture is often present in the air as water vapour (水蒸气).
The problem is how to get this vapour effectively and cheaply from the desert air. And that is what two groups of researchers have managed to do.
The ease with which water can be won from air depends on that air’s relative humidity. This is a measure of its current vapour content as a percentage of its maximum possible vapour content at its current temperature. A relative humidity of 100% means the air in question is holding as much water vapour as it possibly can. A good way to get air to give up some of its moisture is therefore to cool it to the point where its relative humidity is more than 100%. Sometimes this happens naturally at night, causing mist and dew to form. These can be collected in special traps in areas where liquid water is otherwise rarer. But, if night cooling does not bring air all the way up to 100% relative humidity, building water traps out of special materials might give nature a helping hand.
Adsorption (吸附) is a process which pulls water molecules from air that has less than 100% relative humidity by attaching them to the surface of a solid material. The molecules are held there by electrostatic (静电的) connections called Van der Waals forces that link them with the molecules of the related surface. To collect a lot of water this way therefore requires a material that has two features. One is a large surface area. The other is an appropriate Van der Waals response. Experimental traps that employ this principle have been made using substances called metal-organic frameworks. These are porous (多孔的) molecular networks through which air can circulate. Their porosity gives them a huge surface area. And by picking the right ingredients, such as zirconium, they can be given the necessary Van der Waals features. Zirconium is, however, costly. Moreover, once absorbed, the water must then be released. This means warming the absorptive material—the warmth being provided by the sun, once it has risen. Here, metal-organic frameworks present a problem. They tend to reflect sunlight rather than absorb it, and so don’t heat up well. To overcome this, engineers build a solid device made of copper into the system. This works, but adding such devices makes an already costly technology even dearer.
1. What is the meaning of the underlined word in Paragraph 1?| A．The irrigation of sea water. | B．The import of sea water. |
| C．The removal of salt in sea water. | D．The purification of sea water. |
| A．Air quality. | B．Relative humidity. |
| C．Current vapour content. | D．Current temperature. |
| A．Water drops are the major existence of moisture in the air. |
| B．Getting vapour in the air naturally usually happens when the relative humidity is below 100%. |
| C．The more holes a certain material has, the huger surface area it has. |
| D．Zirconium is chosen because it’s cheap. |
| A．Maintaining-fresh water in the desert. |
| B．Introducing a way to get water in the air of the desert. |
| C．Promoting an experimental trap to get water in the air. |
| D．Offering a way to increase adsorption in the air. |
