Chemists have spent the past century trying to make plastics break down in seawater. Most plastics take centuries to fully break down in the ocean.
Timo Rhein Berger is a PhD student at the University of Twente in the Netherlands.
When the researchers weakened 15% of PLA’s monomer links, the PLA broke down entirely within just two weeks. When they weakened only 3% of the links, the breakdown took about two years.
| A．Plastics are useful. |
| B．Scientists created the now-popular plastic in the1930s. |
| C．So researchers have much confidence in their efforts. |
| D．That’s why plastics make up 80% of ocean trash. |
| E．His work has focused on speeding PLA’s breakdown. |
| F．This means the team can design how quickly PLA breaks down in seawater. |
| G．The more breaking points researchers added, the faster the PLA broke down. |
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【推荐1】Students in Cambodia have designed a prototype manned drone (无人机) from a rather unexpected piece of furniture — a school chair. Inspired at first by a desire to beat their city’s notorious (声名狼藉的) traffic, the group designed their prototype drone that they hope can eventually be used to ferry people around Phnom Penh and even fight fires.
With eight propellers (螺旋桨) and using a school chair for the pilot’s seat, the drone was developed by students at the National Polytechnic Institute of Cambodia (NPIC) on the outskirts of the capital. “The drone, when we see it flying without a pilot, there is a lot of shaking. But when I sit on it and fly... it becomes more stable and I feel so excited,” said LonhVannsith, 21, the pilot of the drone. “We wanted to solve some problems for our society by making a taxi drone and ... inventing drones for firefighters,” he said, noting how, for example, they hoped it could reach the upper floors of a building to bring a hose where a fire truck could not reach.
The prototype can carry a pilot weighing up to 60 kg and fly for about 10 minutes for a distance of 1 km. It took three years of research and development and cost around $20,000 to build. While the team hopes it will eventually fly far higher, when manned the drone currently only rises to as much as four meters.
The project faced delays because of lockdowns during the COVID-19 pandemic and also as components like the propellers and the frame had to be ordered abroad, said SarinSerevatha, who is NPIC’s head of research and development technology.
The team plans to improve the design to allow it to take more weight, as well as fly further and more stably at a higher level. “In principle, if we make one drone, the cost is expensive but if we make them to sell on the market, the cost will go down,” said Sarin.
1. What’s the original motivation for the design of the prototype drone?| A．To avoid the busy traffic. | B．To fight fires. |
| C．To earn plenty of money. | D．To amuse people. |
| A．The team is very pleased with it. | B．There is much room to improve it. |
| C．It is popular because of the low cost. | D．It is stable enough to carry passengers. |
| A．Brave. | B．Responsible. |
| C．Creative. | D．Caring. |
| A．A Prototype Manned Drone | B．A New Invention from Students |
| C．The Creative and Imaginative Students | D．From a School Chair to a Manned Drone |
【推荐2】While researchers have recently created soft and flexible robots, they still contain hard electric power and control systems. Now, thanks to a team led by Harvard University professors, Robert Wood and Jennifer A. Lewis, there is finally a breakthrough. The adorable autonomous octobot that stands a mere 2 cm tall has no rigid parts, enabling it to squeeze through the tiniest of spaces, just like octopuses(章鱼).
The octobot, which is mainly made of rubber, is fueled by a mixture of hydrogen peroxide and water. The liquid that is pumped into the robot’s body through a series of 3-D printed chambers(室) reacts with the spots of platinum(铂) that are planted within the octobot and forms water and oxygen. The released gas builds up the pressure in the controller and the chambers in the robot’s arms, causing them to move.
The researchers, who introduced the revolutionary robot in the scientific journal Nature, say that octobot is currently just a proof of concept and not ready for the real world. That’s because the liquid battery only provides power for about eight minutes. Additionally, it lacks controls and therefore cannot be directed in any direction. The team hopes to solve the issues in their next version of the soft robot, which will be able to move, swim, and sense objects in the environment.
Wood believes that the octobot’s easy-to-build design, low cost, and the fact that its fuel ability can be increased will encourage other scientists and roboticists to create more complex designs. The researchers say, “Although soft robotics is still in its beginning stage, it holds great potential for several applications, such as servicing, and inspecting machinery, search-and-rescue operations, and exploration.” Given how adorable they are, we agree with that statement.
1. What is the main characteristic of the octobot compared to the former robots?| A．Shape. | B．Flexibility. | C．Driving pattern. | D．Production cost. |
| A．The octobot’s movement principle. | B．The octobot’s building materials. |
| C．The octobot’s living habits. | D．The octobot’s future market. |
| A．It is perfect in control system. | B．It is still in the step of theoretical research. |
| C．It is useless in real situations. | D．It needs a more powerful battery. |
| A．They are universal. | B．They are impractical. |
| C．They are unprofitable. | D．They are promising. |
【推荐3】Transport has a lot to answer for when it comes to harming the planet. While cars and trains are moving towards greener, electric power, emissions（排放）from air travel are expected to increase massively by 2050. If we want big green sky solutions, we need blue sky thinking. Fortunately, there's plenty of that happening right now, particularly the short - haul flights powered by batteries.
Harbour Air is the largest seaplane airline in North America, flying 30,000 commercial flights in 40 seaplanes each year. Significantly, all Harbour Air routes last less than 30 minutes, making it perfectly fit for electric engines. "As an airline, we're currently in the process of turning all our planes into electric airplanes. says CEO Greg McDougall. To make this happen, the airline has partnered up with MagniX to create the world's first commercial flight with an electric engine.
Making the skies electric isn't just good for the environment, it also makes sound financial sense： a small aircraft uses $ 400 on conventional fuel for a 100 - mile flight, while an electric one costs $ 8 12 for the same distance, and that's before you factor in the higher maintenance costs of a traditional engine. There's also the added bonus that electric planes are just much more pleasant to fly in. No loud engine noise, no smell of fuel, just environmentally friendly peace and quiet.
While there has been real progress in the e-plane industry, the technical challenges that remain are keeping everyone's feet firmly on the ground. A battery, even a lithium one, only provides 250 watt-hours per kilogram； compare this to liquid fuel, which has a specific energy of IL 890 watt-hours per kilogram. Carrying adequate batteries, however, would make the plane too heavy to get off the ground. In aircraft, where every bit of weight counts, this can't just be ignored.
The transition （过渡 ） from gas to electric in the automobile industry has been made easier by hybrids - vehicles powered by both fuel and electricity. Many believe the same pattern could be followed in the air. Fuel consumption could be reduced as the electric component is switched on at key parts of the journey, especially on take-off and landing.
It's certainly an exciting time for electric flying. With companies like Harbour Air taking the lead, battery-powered planes, especially on short-haul journeys, are set to become a reality in the next few years.
1. According to Para l, what is happening in air transport?| A．New explorations of the sky are being launched. |
| B．Pollution caused by batteries is being controlled. |
| C．Efforts are being made to make air travel greener. |
| D．Demand for short-haul flights is increasing massively. |
| A．It runs short routes. | B．It has a strong partner. |
| C．Its planes can land on the sea. | D．It has planes with powerful engines. |
| A．To improve the ground service for e-planes. |
| B．To find qualified technicians for e-plane industry. |
| C．To calculate the energy needed to power e-planes. |
| D．To balance power and weight of batteries in e-planes. |
| A．To produce new electric components. | B．To increase battery consumption. |
| C．To use mixed - power technology. | D．To expand the landing field. |
| A．Short-sighted | B．Wait-and-see | C．Optimistic | D．Skeptical |
【推荐1】"We must learn not to take traditional morals（道德）too seriously." So said the biologist J. B. S. Haldane in a 1923 talk on science and the future. Haldane forecasted that scientific progress would destroy every belief and value. The future would be bright only "if mankind can adjust its morality to its powers". Haldane had a point: our powers have led to challenges that have never existed before. Climate change is a threat unlike any we have ever seen. Our machines might become smarter than us. Genetic engineering（基因工程）could change humanity forever.
In the face of such challenges, our evolved moral sense often proves not enough. Part of the problem is scale（规模）.The anthropologist Robin Dunbar says we can keep no more than about 150 meaningful relationships at once. But today, all 7 billion of us are connected—if not in meaningful relationships, not in meaningless ones, either. “Society" is now too big a concept for our brains to analyze.
One result is conflicting demands that are hard to solve. The bad situation of our fellow humans makes us use every possible way to deal with climate change. But that could hurt our own way of life. And then there's the urge to just forget all that pressure and get on a plane to somewhere sunny. Given this cognitive（认知的）overload, our original emotional responses tend to win out. We do what feels right. But such responses don't necessarily produce the best results. So how can we make sure we do what really is right?
It's a hard nut, but never fear: moral philosophers are on the case. Some, such as those based at the Centre for Effective Altruism in Oxford, UK, aim to maximize the good we can do by quantifying the results of our actions. Many of their suggestions have raised eyebrows: that it may be better to become a generous banker than work for a charity, for example.
Others suggest modifying our moral brains directly, through drugs. The difficulties with this idea are obvious: who decides what makes improvement? Given the practical difficulties of large-scale morality hacking（入侵），we should perhaps stick to education. We are not simply prisoners of our emotions: we can reason our way to workable solutions. Science alone will not get us there. So no, we shouldn't take traditional morality too seriously where it fails to address modern problems.
1. J. B. S. Haldane forecasted that scientific development would ______.| A．lead to the corruption of public morals |
| B．present a challenge to traditional morals |
| C．bring disasters and fears to human beings |
| D．affect human beings powers of adjustment |
| A．collective wisdom is a good solution to modern challenges |
| B．Robin Dunbar thinks it is hard to build up meaningful relationships |
| C．our evolved moral sense is too limited to solve the problems of modern society |
| D．the large scale of social connections makes our relationships less meaningful |
| A．Most people put the blame for modern problems on science. |
| B．Science can help with the modification of our moral brains. |
| C．The combination of reason and humanity can make more effective morality. |
| D．Human beings have a long way to go before they can overcome modern problems." |
【推荐2】Rich variety exists in primates (灵长目动物). Monkeys roll on snowy Japanese mountains, gorillas chew fruit on Sumatra, lemurs jump between trees in Madagascar, and the naked apes—humans—walk proudly on two legs worldwide. Scientists can now study the DNA differences beyond that diversity, thanks to a databank of genomes (基因组) from 233 species.
To understand the good and bad of human evolution—both our extraordinary adaptations and disease-causing changes—scientists must compare the genomes of Homo sapiens (智人) to our closest evolutionary relatives, the primates. But researchers investigating diverse topics, from contemporary genetic diseases to human origins, have long faced a roadblock when pursuing this approach: While genomic data exists from millions of people, most of the 500-plus primate species never had their genomes read. So, in 2019, Tomàs Marquès-Bonet at the Institute of Evolutionary Biology, in Barcelona, Spain, and other biologists teamed up with disease researchers at the company Illumina, determined to obtain as many primate genomes as possible.
Navigating wilderness and local permitting laws, the international researchers obtained hundreds of blood samples from wild and caged animals in South America, Africa, and Asia. Arranging DNA from these samples and adding data from previous studies, the team built a bank of 809 genomes from individual baboons, gorillas, gibbons, and more, representing nearly half the known primate species.
The data revealed insights about human origins and health, as well as primate conservation, published by more than 100 scientists across 10 papers in Science and Science Advances in June 2023. One study trained artificial intelligence to search human genomes for DNA differences likely to cause disease, based on whether nonhuman primates can live with those variants. According to Marquès-Bonet, “We now have a really good list of the foundations of our species” and a “good idea of the kind of variations that are tolerated in any primate”—including humans.
1. What can we learn from paragraph 1?| A．Primates vary mainly in habitats. |
| B．Scientists focus on the diversity of primates. |
| C．There are 233 species of primates in the world. |
| D．Primate genomes are important for studying the DNA differences. |
| A．To cure human’s various genetic diseases. |
| B．To help human adapt to the environment. |
| C．To investigate the process of human evolution. |
| D．To understand the strength and drawback of human evolution. |
| A．The reasons for building the databank. |
| B．The process of building the databank. |
| C．The impacts of building the databank. |
| D．The difficulties in building the databank. |
| A．It still needs to be improved. |
| B．It is of great value to future research. |
| C．It is of little help to future research. |
| D．It is unclear whether it’s of help to future research. |
【推荐3】Transport has a lot to answer for when it comes to harming the planet. While cars and trains are moving towards greener, electric power, emissions from air travel are expected to increase massively by 2050. If we want big green sky solutions, we need blue sky thinking. Fortunately, there’s plenty of that happening right now, particularly the short-haul flights powered by batteries.
Harbour Air is the largest seaplane airline in North America, flying 30, 000 commercial flights in 40 seaplanes each year. Significantly, all Harbour Air routes last less than 30 minutes, making it perfectly fit for electric engines. “As an airline, we’re currently in the process of turning all our planes into electric airplanes.” says CEO Greg Mc Dougall.
Making the skies electric isn’t just good for the environment, it also makes sound financial sense: a small aircraft uses $400 on conventional fuel for a 100-mile flight, while an electric one costs $8-12 for the same distance, and that’s before you factor in the higher maintenance costs of a traditional engine. There’s also the added bonus that electric planes are just much more pleasant to fly in. No loud engine noise, no smell of fuel, just environmentally friendly peace and quiet.
While there has been real progress in the e-plane industry, the technical challenges that remain are keeping everyone’s feet firmly on the ground. A battery, even a lithium one, only provides 250 watt-hours per kilogram; compare this to liquid fuel, which has a specific energy of 11, 890 watt-hours per kilogram. Carrying adequate batteries, however, would make the plane too heavy to get off the ground. In aircraft, where every bit of weight counts, this can’t just be ignored.
The transition from gas to electric in the automobile industry has been made easier by hybrids-vehicles powered by both fuel and electricity. Many believe the same pattern could be followed in the air. Fuel consumption could be reduced as the electric component is switched on at key parts of the journey, especially on take-off and landing.
It’s certainly an exciting time for electric flying. With companies like Harbour Air taking the lead, battery-powered planes, especially on short-haul journeys, are set to become a reality in the next few years.
1. According to Para. l, what is happening in air transport?| A．New explorations of the sky are being launched. |
B．Pollution caused by batteries is being controlled |
| C．Efforts are being made to make air travel greener. |
| D．Demand for short-haul flights is increasing massively. |
| A．give passengers more pleasant views |
| B．bring airlines more financial benefits |
| C．offer more enjoyable flying experiences |
| D．cost less in maintenance than traditional ones |
| A．To improve the ground service for e-planes. |
| B．To find qualified technicians for e-plane industry. |
| C．To calculate the energy needed to power e-planes. |
| D．To balance power and weight of batteries in e-planes. |
| A．To produce new electric components. |
| B．To increase battery consumption. |
| C．To use mixed-power technology. |
| D．To expand the landing field. |
| A．Short-sighted. | B．Wait-and-see | C．Optimistic. | D．Skeptical. |
【推荐1】A team led by researchers from the UK examined waterbird data from 1506 protected areas and analyzed more than 27, 000 bird populations across the world. They compared waterbird populations before and after the establishment of protected areas and also compared trends of similar populations within and outside of protected areas.
“Our study shows that, while many protected areas are working well, many others are failing to have a positive effect, ” lead author Hannah Wauchope says in a statement. “In the majority of places we looked, bird populations were stable or were increasing, but some of them weren’t doing any better than in unprotected areas, “ she adds. “That’s disappointing, but not surprising. There seems to be the disconnection between people talking about how much land is protected and whether those areas are actually doing anything positive. ”
This study comes ahead of a United Nations meeting in China to discuss biodiversity goals for the next decade. Several countries have already committed to protecting 30 percent of the planet by 2030, yet the researchers say this alone does not necessarily guarantee positive out- comes for species.
“An obsession(迷恋)with reaching a certain area-based target-such as 30 percent by 2030-without focus on managing existing protected areas appropriately will achieve little, ” co-author Julia Jones says. “When world leaders gather in China later this year to set targets for the next decade, I really hope to see a change of their focus, rather than simply saying how much surface area they are going to protect. ”
According to Thomas Brooks, chief scientist at the International Union for Conservation of Nature, who was not involved in the study, waterbirds are a good example of a group facing the consequences of human behaviors that cause biodiversity loss. These animals respond quickly to changes in site quality and are broadly distributed, clearly reflecting the impact of protected areas.
1. What can be learned about protected areas from the study?| A．They have a negative effect on wildlife. |
| B．Their bird populations are increasing. |
| C．Their problems went unnoticed at all. |
| D．They don’t always help waterbirds. |
| A．Expanding protected areas. |
| B．Organizing the meeting. |
| C．Talking about biodiversity. |
| D．Making a big promise. |
| A．Try to set targets for the next ten years. |
| B．Focus on the effectiveness of protected areas. |
| C．Face the consequences of human behaviors. |
| D．Have a deep understanding of biodiversity. |
| A．Pioneering. | B．Disappointing. |
| C．Convincing. | D．Unsatisfying. |
【推荐2】Heritage on the Edge
In an effort to preserve some of the world’s most famous landmarks，Google has announced a new project to transform a few of the most endangered by climate change into interactive 3D models，just in case one or all is irreparably(不能恢复地)damaged in the coming decades.
Edinburgh Castle
Edinburgh Castle comprises 27 buildings on top of an extinct volcano. It was home to many kings and queens. But old roofs and rainwater management systems will become insufficient as they will be unable to deal with the level of storm water associated with extreme weather events. Besides，if temperatures continue to rise，the rate of decay(腐烂)will increase further.
Kilwa Kisiwani
Kilwa Kisiwani was a regional center of the medieval trading civilization along the East African Coast. Its permanent architecture included ports，Muslim buildings，and the unique“stone houses”. However，the drier weather and subsequently heavy rainfall is threatening the stability of the ruins，causing the worsening of this exposed heritage site.
Mosque City of Bagherat
The Mosque City of Bagherat was once a lost city. It has many Muslim buildings，bridges，roads and palaces. A recent report stressed the increasing impacts of sea level rise and changes in salinity(盐度)on this community. Increased salinity not only makes much of the water undrinkable but damages structures.
Chan Chan
Chan Chan was the capital city of Chimu empire，stretching for nearly a thousand kilometers along the coastline. The city planning reflects a strict political and social strategy. But site managers today face challenges in rainfall and droughts due to El Nino events and climate change that threaten to gradually wash the ancient city away.
1. What do we know about Edinburgh Castle?| A．It was built along the coast. | B．It is the largest castle in the world. |
| C．It is in danger of being washed away. | D．It used to be the home of royal families. |
| A．Water pollution. | B．Water’s becoming salty. |
| C．Water shortage. | D．Water’s being overused. |
| A．Temperature rises. | B．Volcanic eruptions. |
| C．Sea water. | D．Environmental damage. |
【推荐3】A United Nations-backed mission is recommending that the Great Barrier Reef(大堡礁) should be added to the list of endangered World Heritage sites, warning that without “ambitious, rapid and sustained”climate action the world’s largest coral reef is in peril.
The warning came in a report published Monday following a 10-day mission to the reef last March by officials from UNESCO and the International Union for Conservation of Nature.
The reef, a living place of great variety and beauty on the north-east coast of Australia, has been on UNESCO’s World Heritage List since 1981.
Australia’s federal government and Queensland’s state authorities should adopt more ambitious emission reduction targets, in line with international efforts to limit future warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since pre-industrial times, according to the report.
Feedback from Australian officials, both at the federal and state level, will also be reviewed before UNESCO, the U.N.’s Paris-based cultural agency, makes any official proposal to the World Heritage Committee.
The text is criticizing about recent efforts to stop mass bleaching(褪色) and prevent pollution from ruining the reef’s natural waters, saying they have not been fast nor effective enough. Unlimited emissions lead to increased water acidity, which can be poisonous.
More money should be found to increase the water quality and stop the site’s decline, the report concludes.
In an email to AP, the U.N. cultural agency said: “In recent months, we have had a constructive dialogue with Australian authorities. But there is still work to be done.”
1. What does the underlined word “in peril” mean in paragraph 1?| A．in short | B．in need | C．in action | D．in danger |
| A．It needs to be examined by UNESCO. |
| B．It covers successful emission reduction targets. |
| C．It includes many effective measures to protect the reef. |
| D．It has been submitted to the World Heritage Committee. |
| A．Australian authorities’ efforts. | B．Unlimited emissions. |
| C．United Nations’ warning. | D．Money for increasing the water quality. |
| A．Doubtful. | B．Satisfied. |
| C．Objective. | D．Uncaring. |
