1 . 400 million tons of plastic are generated annually, most of which comes from single-use plastic While countries are making progress in reducing this waste through paper bags and straws, there are still applications where the properties of plastic are necessary.
Transparent (透明的) wood is an alternative for such applications and is highly preferred since it prevents the harm of petroleum-derived (石油衍生的) plastic products. German scientist Siegfried Fink first created transparent wood in the year 1992, and over the past three decades it has been significantly improved by other researchers as well.
In its natural form, wood is not transparent. However, researchers have found that removing lignin, a naturally occurring biopolymer that provides structural support for the plant tissue, can make it transparent. To do so, the wood is soaked in a warm solution consisting of multiple chemicals, followed by boiling it in another solution. This removes the lignin completely and turns the wood white. However, the space that was occupied by lignin needs to be filled up to maintain structural integrity. This process is done by using a resin (树脂) at a temperature of 185 Fahrenheit (85℃).
The final product can have as much as 90 transparency, and it doesn’t break easily. More importantly, it is more biodegradable than glass or plastic.
While transparent wood isn’t commercial yet, it has been employed in a wide variety of applications ranging from construction to energy storage, making flexible electronics and packaging.
The researchers at the Indian Institute of Technology ( IIT) conducted a life-cycle analysis (LCA) of transparent wood to determine the environmental impact of its production and end-of-life (EOL) cycle. The study found that using hydrogen peroxide for delignification, followed by using epoxy for infiltration, was the most eco-friendly. When scaled up for industrial production, the former method would lower electricity consumption by as much as 98. 8 percent.
EOL analysis showed that transparent wood had a reduced ecological impact compared to polyethylene (聚乙烯), paving the way for it to be commercially adapted to replace the petroleum-based material.
1. Why is transparent wood preferred compared to plastic?A.It is easier to make. | B.It is environmentally friendly. |
C.It can be used longer. | D.It can be used repeatedly. |
A.The natural form of wood. | B.The importance of chemicals. |
C.How transparent wood is made. | D.How lignin keeps wood strong. |
A.It can be recycled. |
B.It will replace plastic soon. |
C.The most eco-friendly way to produce it. |
D.Potential damage caused by it to the environment. |
A.Promising. | B.Difficult. | C.Profitable. | D.Uncertain. |
2 . In recent years, the popular idea of reducing carbon footprints by eating locally to cut down food miles has come under close examination. However, a recent study published in Nature Food indicates that global food miles might account for as much as 20 percent of food-related emissions, a significantly higher percentage than previous estimations. This statement begs the question: Are food miles more significant than we initially believed?
Food miles represent the distance food travels from production to consumption, with previous studies suggesting that the emissions from these miles are tiny compared to the emissions produced during the food growing process. For instance, producing one kilogram of beef generates almost 99 kg of CO2, while apples only produce 0.4 kg per kilogram. If the goal is to minimize dietary carbon footprints, it would be more beneficial to choose foods with lower overall carbon footprints, even if they have to travel a distance. Therefore, reducing meat and dairy intake could prove to be a more effective strategy.
The recent study doesn’t contradict (相矛盾) this conclusion. The reason why the reported proportion is higher is that the calculation includes all transport involved, including the transportation of fertilizers, farm equipment, and pesticides (杀虫剂). Hannah Ritchie, a researcher at the University of Oxford, suggests that a term other than “food miles” would be more appropriate to avoid any confusion. If the study had followed the standard definition of food miles, the per-centage would drop to 9 percent, which corresponds more closely with the 4 to 6 percent found in prior research.
Moreover, the study theorizes that even if all food was produced in the countries where it is consumed, the reduction in emissions would only be 1.7 percent overall. This is due to the fact that a larger proportion of food would be transported by road rather than by sea, with trucks producing higher emissions per ton of cargo than ships.
“So, overall, the bottom line is still that what you eat has a much bigger impact on emissions than the distance that food has to travel to reach you,” said Ritchie.
1. What has the recent study found?A.Food production has caused a lot of carbon emissions. |
B.Carbon emissions from food miles are increasing rapidly. |
C.Carbon emission reduction largely depends on eating locally. |
D.Global food miles lead to more carbon emissions than expected. |
A.To explain the benefits of apples |
B.To highlight food production’s effect |
C.To compare beef and apple production |
D.To advocate short-distance transportation |
A.Supplying high-calory foods |
B.Upgrading food delivery systems |
C.Reducing meat and dairy consumption |
D.Avoiding chemical pesticides for plants |
A.Unfavourable. | B.Supportive. | C.Tolerant. | D.Uncertain. |
3 . As the Earth turns, its rotational axis (自转轴) naturally move a bit. Anything from ocean currents, to shifting molten rock under the crust, to the melting (融化) of glaciers caused by climate change can cause the axis to drift (飘移). Water stored in artificial lakes and seasonal changes in atmospheric winds can play a role as well.
But global warming isn’t the only human-caused factor moving the planet’s axis as some of us believe. A new study estimates that between 1993 and 2010, the pumping of groundwater and the resulting sea-level rise caused the axis lo drift by about 2.6 feet. “Every mass moving around on the surface of the Earth can change the rotational axis,” said Ki-Weon Seo, a geophysicist at Seoul National University.
In the study, the researchers used a computer model to look at the effects of different factors on the shift of the axis. When they didn’t include groundwater removal in their model, their predictions did not match the level of shift that scientists have observed. But when they look into account the massive amount of pumped water — which totaled more than two trillion tons between 1993 and 2010 ― their model fit the real-world observations. From this analysis, the researchers estimate that the axis is moving 1.7 inches per year due to groundwater removal. Of the factors the study looked at, pumping groundwater was the second-largest contributor to the axis drifting, behind the melting Greenland ice sheet.
The paper calls attention to just how much water humans have pumped, as Clark Wilson, a geoscientist at the University of Texas, tells Science. “The precise number doesn’t matter really. What matters is that the volume is so huge that it can impact the polar drift of the Earth,” he says. “Groundwater removed from sites at the Earth’s midlatitudes (中纬度), such as in the U.S. and India, has a large impact on polar drift, compared with extraction at the equator or the poles. However, most of the pumping has occurred in these high-impact zones, causing the water removal to have a bigger effect on the axis,” says Wilson.
1. What does the author aim to do with the second paragraph?A.To correct a wrong belief. | B.To describe a phenomenon. |
C.To provide related data. | D.To test a new theory. |
A.putting it to field tests |
B.storing related information in it |
C.comparing it with real-world facts |
D.doing real-world observations with it |
A.The melting of ice sheet. | B.The atmospheric winds. |
C.The artificial lakes. | D.The groundwater pumping. |
A.Factors That Affect the Earth’s Rotation |
B.Challenges of Groundwater Our World Faces |
C.Climate Change Has Shifted the Earth’s Axis |
D.Groundwater Pumping Has Changed the Earth’s Axis |
4 . In 2008, when National Geographic Explorer and photojournalist Martin Edstrom learned about the discovery of Hang Son Doong in Vietnam, he realized the cave’s vast “room”—as large as a city block—would be a perfect showcase for the 360-degree and virtual reality(VR) technologies he was using. And while he loves heading to remote places, he doesn’t regard this part of his work as “exploration”. “I find that going to these remote and challenging places brings out the best in me creatively,” he says.
Edstrom traveled with a small team deep into the jungle to reach the remote entrance to the cave. There, they used robotic camera heads, a single DSLR and several smaller camera rigs to build immersive(沉浸的), 360-degree environments that viewers could “inhabit” via VR headsets. This technology was beginning to go mainstream, with Facebook launching their 360-video service in 2015.
The media that Edstrom and his team created allows people to have an intimate (亲密的)—though digital—experience of a natural wonder that few will ever witness firsthand. “The joy of this is really that I get to step out of these restrictions of the frame. I can put people inside the experience,” Edstrom explains. “They get to see what I see.”
Inspiring wonder of the natural world can also help catalyze positive action. The discovery of Hang Son Doong prompted great interest from investors looking to capitalize on the site’s heritage value, including one company that proposed running a cable car through a section of the cave. By drawing international attention to the cave, Edstrom’s 360-degree interactive videos may have played a part in ensuring its preservation: for now, just one tour operator is licensed by the Vietnam government to conduct expeditions to Hang Son Doong, and these are limited to four days. For Edstrom, this is exactly the kind of outcome he’s looking for.
1. Why did Edstrom travel to Hang Son Doong?A.To attend a photo exhibition. |
B.To test a new VR technology. |
C.To photograph for a magazine. |
D.To explore further into the cave. |
A.It is supported by simple equipment. |
B.It is similar to Edstrom’s technology. |
C.It is still leading the world in VR technology. |
D.It is designed for Hang Son Doong tourists. |
A.Deal with. | B.Figure out. | C.Keep up. | D.Bring about. |
A.Satisfied. | B.Confused. | C.Guilty. | D.Worried. |
5 . Ecofriendly replacement products for single-use plastics are appearing everywhere. But have you heard of edible (可食性的) straws? Now EQUO, a new eco-friendly company in Vietnam has come up with a natural edible solution to plastic or paper straws.
The edible straws are completely plastic free, nontoxic, chemical free, and 100 percent biodegradable according to a company press release.
“It’s well known that plastic straws are harmful to the environment. Most of the 500 million used every day in America end up in oceans where they pollute water and harm marine life. Currently over eight billion straws pollute the world’s beaches,” said Marina Tran-Vu in the press release. “Although there are some plastic and paper straw alternatives on the market, most are environmentally harmful, and we were also unsatisfied with the quality and lasting of paper straws.”
All of the materials are locally from regions that support sustainable farming according to the company’s website and they struggle to have zero-net influence by” using the power of mother nature”. The name of the company was created by combining “ECO” — meaning environmentally friendly — with “STATUS QUO” — meaning the existent state. EQU stands for creating products that have minimal influence on the environment. The company was first shown on Kickstarter on May 18 and hit their funding goal in only 30 days.
Many countries are banning single-use plastics. The EU banned 10 single-use plastic products including straws that will take effect in 2021. Other items that will no longer be made of plastic include cutlery (餐具), and balloon sticks. These 10 items make up a large percentage of ocean waste that harms marine life.
So do your part, use biodegradable cutlery — you can carry your own , edible straws, and reusable water or coffee cups. These small items can contribute to reducing plastic waste.
1. What is the third paragraph mainly about?A.The popularity of plastic straws. |
B.The harm of plastic straws. |
C.The pollution of beaches. |
D.The necessity of change. |
A.It means the original aim. |
B.It means the existent state. |
C.It means how to create products. |
D.It means being good for the environment. |
A.Plastic straws will be forbidden. |
B.Edible straws will be sold cheaply. |
C.Ocean waste can be rid completely. |
D.Single-use plastic products will disappear. |
A.Skeptical. | B.Objective. | C.Tolerant. | D.Approving. |
Xixi, located less than five kilometers from the West Lake in the west of Hangzhou, is China’s first national wetland park. The area covers about 10 square kilometers and it
Wetlands themselves are one of the most biologically diverse ecosystems,
Xixi’s native vegetation,
7 . When scientists and the public worry about sea level rise, they mostly focus on when and where communities will be permanently flooded. But there’s another consequence of rising seas that will affect many more people much sooner: getting cut off from roads and other critical infrastructure (基础设施). It’s a threat that society has not paid nearly enough attention to, says Allison Reilly, a civil engineer at the University of Maryland.
In a new paper, Reilly and her colleagues show the width and pace of the isolation (隔离) threat. Inspired by her work on the eastern shore of Maryland, where people already need to adjust their travel and work schedules to account for tides that frequently flood roads, Reilly and her colleagues calculated that, with one meter of sea level rise, twice as many people across the coastal United States will be isolated than will be fully flooded.
Worse still, many places currently considered at low risk of sea level rise suddenly become much riskier when isolation is taken into account, Reilly says. While planners know that low-lying Florida will be severely flooded, Maine, with its high rocky coasts, is generally thought to be at low risk. But Reilly’s work shows many Mainers are in great danger of being cut off by flooding in coastal communities and river valleys.
This far more immediate effect of rising seas needs to become part of the broader planning process. That kind of planning is starting to happen around the Chignecto Isthmus, an interprovincial land bridge in Canada, connecting New Brunswick and Nova Scotia. The New Brunswick and Nova Scotia governments are considering a variety of plans to raise or replace the dikes (坝). For Ollerhead, a Nova Scotian, that work can’t start soon enough. “It will take a lot of sea level rise before Nova Scotia becomes an island, but you could have a storm that cuts off the major transportation links for days, weeks, or months,” he says. “It’s nearly impossible to predict when, but it will happen eventually.”
1. What is the threat Allison Reilly mentioned in paragraph 1?A.The rising sea level. | B.Flood-related isolation. |
C.Permanent flooded areas. | D.Irreparable infrastructure. |
A.Conclusions of a new paper. | B.Calculations of collected data. |
C.Situations of Eastern Maryland. | D.Influences on coastal United States. |
A.To clarify a point. | B.To offer a solution. |
C.To present an assumption. | D.To illustrate a reason. |
A.Dismissive. | B.Doubtful. | C.Favorable. | D.Unclear. |
8 . More than 80 percent of global heat is absorbed by the ocean, which has a massive capacity to store and give off heat. High sea-surface temperatures are causing long-term damage to coral reefs (珊瑚礁). Corals are dying. The IPCC (政府间气候变化专门委员会) projects that up to 90 percent of coral reefs could disappear if global warming reaches 1.5℃. Another reason corals are in trouble is because of ocean acidification. Higher carbon dioxide levels have shift ed the chemistry of the ocean, making it more acidic, and corals and sea creatures have trouble growing in acidic conditions.
When ocean water warms, it expands in volume. This is a major cause of the rise in sea levels, along with the water added to the ocean by the melting of land-based glaciers (冰川). The sea level has risen by an average of 20 centimeters since the late 19th century, and the research by scientists studying the last 25 years of satellite data found that the ocean water is rising faster and faster. If it continues at its current rate, the rise in sea level by 2100 will be more than double the current estimates. Sea level rise leads to the destruction of coastal wetlands, flooding and damage to water ecosystems.
Temperature and precipitation (沉淀) are key elements of climate. A warmer climate means that more water rises from both the land and ocean, and a warmer atmosphere holds more of that water. Scientists have noticed that there are more heavy rainfall events. Additionally, higher water temperature in streams, lakes, and rivers lead to lower levels of dissolved oxygen in the water, which impacts the survival and populations of fish and other sea life.
Especially troubling are the extreme weather events that are happening more often around the world. Hurricanes are ramping up in intensity, particularly in North Atlantic. The year 2017 was a busy one for Atlantic hurricanes. Meanwhile, in the western United States, the state of California has had record-setting drought conditions, which began in 2012.
1. What does the author intend to tell us in Paragraph 1?A.Global warming has little damage to the land. | B.Ocean acidification affects the sea temperature. |
C.Coral reefs are in danger of disappearing. | D.Corals and sea creatures need critical surroundings. |
A.Sea level rise has positive effect on sea animals. |
B.By 2100 the sea level will rise 20 centimeters. |
C.Global heating is the direct cause of wetlands destruction. |
D.The rise of sea level is beyond our imagination. |
A.Increasing. | B.Failing. | C.Appearing. | D.Changing. |
A.High Sea-surface Temperatures to Creatures | B.Global Warming, What Damages It Causes |
C.Ways to Stop High Sea-surface Temperatures | D.Extreme Weather Events and Global Warming |
1. What is the campaign’s main goal?
A.To encourage people to reduce garbage. |
B.To ask people to protect the environment. |
C.To warn people of the bad effects of cars. |
A.Planting trees. | B.Painting posters. | C.Collecting garbage. |
A.Hang posters. | B.Stop driving cars. | C.Decorate classrooms. |
A.Impractical. | B.Confusing. | C.Wonderful. |
10 . We’re all familiar with the idea of climate change and how our planet is warming. Extremes in temperature have become more commonplace, making parts of the world difficult to live in. But one place where extreme heat is making life very uncomfortable is our cities. Luckily, innovation might be keeping it under control.
As thermometers(温度计) record temperatures, sometimes above 50 degrees Celsius, solutions are being sought to cool the air in our cities. In India, for example, heatwaves and rapid urbanization have led to a big rise in the use of air-conditioning units, adding to CO2 emissions. So, architects, looking for a sustainable cooling solution, are copying an ancient lattice (框架) design, used in old buildings like the Taj Mahal, to construct comfortable,low-carbon buildings. Yatin Pandya told the BBC: “Traditional architectural forms have proven their performance in combating environmental conditions.”
In America, about 80% of the population lives in cities, and it’s these cities that suffer from an urban heat island effect, caused by factors such as trapped waste heat, concrete structures and pavements absorbing the sun and tall buildings blocking the wind. Residents and developers have tried to cool these places by planting large trees that offer shade and putting plants and gardens on top of roofs to help trap heat. And in Los Angeles, there’s a experiment to cover street s with light-coloured material that reflects rather than absorbs the sun and so they remain cooler than typical black roads.
But it’s satellites in space that are really giving us the best picture of our over-heated cities. Glynn Hulley, who is leading an image-capturing project, called the Land Surface Temperature Monitoring mission, told the BBC: “The data can be used to identify hot spots, weak regions, and assess the cooling impacts of heat mitigation (缓解) approaches.” It’s already found how green spaces, white roads and water features, have helped prevent our cities from boiling over. But with extreme heat still posing a threat to our lives, more solutions are still needed.
1. What leads to the increase of CO₂ emissions?A.Invention of thermometers. | B.Imitation of traditional architecture. |
C.Building of concrete structures. | D.Application of air-conditioning units. |
A.To prove it is miserable to suffer from heat. | B.To show people are trying to solve problem. |
C.To demonstrate the benefit of modern buildings. | D.To support the idea of low-carbon construction. |
A.Evaluating the cooling effect. | B.Identifying city features |
C.Emphasizing threats to lives | D.Testing image capturing technology. |
A.Cities in Danger | B.Dramatic Climate Change |
C.Temperature Monitoring Mission | D.Cooling Hot Cities |