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The Arizona desert is really dry. Anyone stuck in it without water would die from dehydration（脱水）within three days. Unless, that is, they had one of Omar Yaghi’s next-generation water harvesters. Although daytime humidity（湿度）is only about 10 per cent, this rises to 40 per cent at night, which means there’s enough water in the atmosphere to support life — if it can be changed into liquid form.
That’s exactly what Yaghi’s device does. It’s a box about the size of a small microwave oven designed to suck the humidity from the air at night and turn it into drinking water the next day using only the heat of the sun as its power source. What makes it work is a powder called a metal-organic framework (MOF), which at normal temperatures attracts water molecules (分子) onto its surface. Warm it up and the water is released, each harvest producing one-third of a cup of pure drinking water. “With further improvements, a device, the size of a washing machine, could produce enough water for the basic needs of a household,” says Yaghi, a chemist at the University of California.
One-third of the world’s population lacks safe drinking water; for them such a device could be a lifesaver. But that’s not the limit of the MOF technology.
Just as MOFs can help solve the problem of water shortage, they offer a way of reducing a lot of greenhouse gases. In April this year, the carbon dioxide levels in the atmosphere hit an 800,000-year high, contributing to climate change. Recent research suggests ways that MOFs might be able to help mitigate（缓解）this danger to the Earth’s ecosystem.
An international team led by chemists from the University of Manchester, UK, reported in 2018 that they had developed an aluminum (Al)-based MOF that can selectively and repeatedly remove another gaseous pollutant, nitrogen dioxide (NO2), from the surrounding atmosphere. This discovery could lead to air-related technologies that seize and change large quantities of other gases, such as carbon dioxide, to reduce air pollution.
In 2017, a MOF startup pioneer NuMat Technologies employed MOFs to safely store and deliver dangerous gases. For a given pressure, a tank containing a MOF holds more gas than one without. Or, to put it another way, if a gas tank has a MOF in it, then it does not need to be as highly pressurized in order to hold the same amount of gas, making it safer and less likely to explode, and possible less expensive.
Now, about two dozen companies in the past five years are known to be pursuing MOFs, from small startups to larger chemical and automobile companies. And QYResearch forecasts that the MOF market will grow from $70 million in 2017 to $750 million in 2025. “The potential here is just endless,” says Yaghi. “As cheaper materials come into focus, there will continue to be even more opportunities for commercialization.”
1.MOF changes the sucked humidity into water by ________.
A. lowering the temperature
B. collecting carbon dioxide
C. recycling dangerous gases
D. absorbing the heat of the sun
2.Aluminum-based MOF can be used to _______.
A. reduce greenhouse gases
B. produce household water
C. deliver dangerous gases
D. release water molecules
3.It can be learned that under the same pressure, a tank with a MOF will _______.
A. cost more money B. cause more explosions
C. hold more gases D. afford more crashes
4.The main purpose of this passage is to ______.
A. explain how to use MOF
B. describe the future of MOF
C. persuade people to buy MOF
D. introduce the functions of MOF
高三英语阅读理解困难题查看答案及解析
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阅读理解。
Visitors to the dry, hot Sonoran Desert of the southern Arizona and northern Mexico are amazed at the manyarmed giants. They are the saguaro cacti (树形仙人掌), a giant which gives the landscape its _____________ appearance. In the dry desert the saguaro cacti can live for more than 200 years, grow to a ___________ of 60 feet, and have as many as 50 arms.
More __________， the saguaro cacti still persist despite the unbearable desert climate. Those that have grown to old age have ___________ droughts, freezes, flash floods, and bush fires as well as the ___________ caused by groups of rats that eat their seedlings (秧苗). Like all other desert ___________， these leafless giants can store water for use during the desert's long dry seasons by ____________ water through their long roots.
Naturally, the great saguaro cacti are a(n) __________ part of the desert life. Actually the giants may be ___________ to many animals, including woodpeckers, owls, doves, bats and insects. In addition, after a saguaro __________ the age of 50 or so, coldresistant flowers ___________ at the top of the plants once a year. These flowers ____________ birds, bats and bees, which come for the honey and for the tasty flowers with their black seeds.
___________ the splendid saguaros are plentiful in the Southwest, they are unfortunately ___________. These giant cacti have great value in landscape gardening, and the thieves can earn thousands of dollars by uprooting and __________ them to nurseries (苗圃). To protect these southwestern ___________， agents for the Arizona Department of Agriculture go around and __________ the desert. It's a most important job though a hard one. But without the saguaro cacti, many desert animals would suffer a lack of __________ and loss of nesting sites. The Southwest, too, would ____________ something of unique importance, since these desert giants have become a ____________ of the dry region.
1.A.general B．basic C．unique D．lovely
2.A.length B．height C．size D．width
3.A.pleasingly B．inspiringly C．interestingly D．amazingly
4.A.lived through B．broken through C．cut through D．got through
5.A.crisis B．damage C．destruction D．load
6.A.plants B．lives C．animals D．creatures
7.A.pouring B．squeezing C．pumping D．absorbing
8.A.independent B．vital C．original D．mysterious
9.A.spot B．field C．home D．camp
10.A.turns B．takes C．meets D．gains
11.A.come up B．come out C．show off D．show up
12.A.call B．trap C．fascinate D．stick
13.A.As B．But C．Although D．Yet
14.A.in danger B．in demand C．in need D．in control
15.A.exchanging B．trading C．offering D．selling
16.A.treasures B．decorations C．possessions D．creations
17.A.look over B．hand over C．watch over D．turn over
18.A.food B．scenery C．water D．flavor
19.A.affect B．abandon C．increase D．lose
20.A.signal B．sign C．mark D．symbol
高三英语完形填空中等难度题查看答案及解析
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No matter how________, it is not necessarily lifeless.
A. a desert may be dry B. dry a desert may be
C. may a desert be dry D. dry may a desert be
高三英语单项填空简单题查看答案及解析
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No matter how________ , it is not necessarily lifeless.
A. a desert may be dry B. dry a desert may be
C. may a desert be dry D. dry may a desert be
高三英语单项填空中等难度题查看答案及解析
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No matter how________, it is not necessarily lifeless.
A.dry may a desert be B.a desert may be dry
C.may a desert be dry D.dry a desert may be
高三英语单项填空中等难度题查看答案及解析
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No matter how________, it is not necessarily lifeless.
A. dry a desert may be B. a desert may be dry
C. may a desert be dry D. dry may a desert be
高三英语单项填空困难题查看答案及解析
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In the dry Namib Desert on the west coast of Africa, one type of beetle has found a special way of surviving. When the morning arrives, the Namib Beetle collects water drops on its bumpy(起伏不平的) back, then lets the water roll down into its mouth, allowing it to drink in an area without flowing water.
Shreerang Chhatre wants to use what nature has developed to help the world’s poor. Chhatre is an engineer at MIT who works on fog harvesting, the equipment that, like the beetle, attracts water drops. This way, poor villagers could collect clean water near their homes, instead of spending hours carrying water from distant wells or rivers.
Access to water is a serious global issue. According to the World Health Organization and UNICEF, nearly 900 million people worldwide live without safe drinking water. The burden of finding and transporting water falls heavily on women and children. “As a middle-class person, I think it’s terrible that the poor have to spend hours a day walking just to obtain a basic necessity,” Chhatre says.
A fog-harvesting machine consists of a fence-like mesh panel(网状面板), which attracts drops, connected to containers into which water falls. Chhatre has improved the materials used in these machines. He is continuing his work at MIT Sloan and the Legaturn Center in order to develop a workable business plan for applying fog-harvesting machines.
Interest in fog harvesting dates back to the 1990s, and has increased since new research on the Namib Beetle became famous in 2001. A few technologists saw potential in the concept for people. One Canadian charitable organization, FogQuest, has tested projects in Chile and Guatemala.
But fog harvesting remains in its childhood, technologically and commercially, as Chhatre readily recognizes. “It still faces some open problems,” he says. “But it’s a work in progress.” After all, the water that fills our rivers and lakes comes from air.
1.Which of the following is TRUE of Shreerang Chhatre?
A. He is an African engineer.
B. He is researching on the Namib Beetle.
C. He has made the first fog-harvesting machines to use.
D. He is trying to put fog-harvesting machines to use.
2.Why is Namib Beetle mentioned in the passage?
A. To describe the severe conditions in Namib Desert.
B. To introduce the diversity of species in Namib Desert.
C. To inform how animal nature can be used to benefit people.
D. To raise the awareness of accessing clean drinking water in poor areas.
3.The underlined word “it” in the last paragraph refers to _________.
A. UNICEF B. the beetle
C. fog harvesting D. a Canadian charitable organization
4.The author’s main purpose in writing the text is to ________.
A. stress the importance of saving water
B. show the Namib Beetle’s special way of surviving
C. introduce a new machine for collecting water from air
D. inform people of the serious water problem in Africa
高三英语阅读理解中等难度题查看答案及解析
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The worst outbreak of desert locusts (蝗虫) in decades is presently underway in the Horn of Africa. It is the biggest of its kind in 25 years for Ethiopia and Somalia — and the worst Kenya has seen for 70 years.
What we are seeing in East Africa today is unlike anything we’ve seen in a very long time. Its destructive potential is enormous, and it’s taking place in a region where farmers need every gram of food to feed themselves and their families. Most of the countries hardest hit are those where millions of people are already vulnerable (脆弱的) or in serious humanitarian need, as they endure the impact of violence, drought, and floods.
We have acted quickly to respond to this outbreak. The primary method of battling locusts is the aerial spraying of pesticides (杀虫剂). FAO’s “Locust Watch” service explains that “although giant nets, flamethrowers, lasers, and huge vacuums have been proposed in the past, these are not in use for locust control. People and birds often eat locusts but usually not enough to significantly reduce population levels over large areas.”
The UN’s Office for the Coordination of Humanitarian Affairs has released $10 million from its Central Emergency Relief Fund to fund a huge scale-up in aerial operations to manage the outbreak.
But the window to contain this crisis is closing fast. We only have until the beginning of March to bring this infestation under control as that is when the rain and planting season begins. If left unchecked — and with expected additional rains — locust numbers in East Africa could increase 500 times by June.
We must act now to avoid a full-blown catastrophe. And we will. At the same time, we need to pay attention to a bigger picture. This is not the first time the Greater Horn of Africa has seen locust outbreak approach this scale, but the current situation is the worst in decades. This is linked to climate change. Warmer seas mean more tropical storms, generating the perfect breeding conditions for locusts.
1.What is implied in paragraph 2?
A.People in East Africa are suffering drought.
B.People in East Africa are going through floods.
C.The locust outbreak will cause crop failure.
D.The locust outbreak is worsening locals’ life.
2.What can we learn from the last paragraph?
A.We need a bigger picture to study the disaster.
B.It is the second outbreak of locusts in East Africa.
C.It is the largest outbreak of locusts ever in history.
D.The outbreak of locusts is fueled by global warming.
3.What is the purpose of the text?
A.To analyse and compare. B.To inform and call for.
C.To argue and discuss. D.To introduce and assess.
4.Where does the text probably come from?
A.A guidebook. B.A health magazine.
C.A news report. D.A chemistry paper.
高三英语阅读理解中等难度题查看答案及解析
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Living alone in the central desert in Australia has its problems,________obtaining water is not the least.
A. of which B. for what C. as D. whose
高三英语单项填空中等难度题查看答案及解析
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Having been stuck in the cave for six days without food or water, the young man lay on the ground, _____.
A．considerate
B．conscious
C．senseless
D．sensitive
高三英语单项填空简单题查看答案及解析