University of Minnesota Twin Cities College of Science and Engineering researchers have invented a cheaper, safer, and simpler technology that will allow a “stubborn” group of metals and metal oxides to be made into thin films used in many electronics, computer components, and other applications. The researchers applied for a patent for the technology and have already gained interests from industry.
Many metals and their compounds must be made into thin films before they can be used in technological products like electronics. “Stubborn” metals are very difficult to convert into thin films because they require extremely high temperatures (usually more than 2, 000 degrees Celsius) to evaporate (蒸发). Typically, scientists combine these metal films using techniques like sputtering and electron beam evaporation (溅射和电子束蒸发). The latter consists of melting and evaporating metals at high temperatures and allowing a film to form on the top. But, this conventional method is very expensive, uses a lot of energy, and may also be unsafe due to the high voltage used.
Now, University of Minnesota researchers have developed a way to evaporate these metals at significantly lower temperatures, fewer than 200 degrees Celsius instead of several thousands. By designing and adding organic ligands (配体)—combinations of carbon, hydrogen, and oxygen atoms—to the metals, the researchers were able to substantially increase the materials' vapor pressures, making them easier to evaporate at lower temperatures. Not only is their new technique simpler, but it also makes higher quality materials that are easily expanding.
“The ability to make new materials with ease and control is essential to transition into a new era of energy economy,” said Bharat Jalan, the senior author of the study. “There is already a historical link between the innovation (革新) in synthesis science and the development of new technology. Millions of dollars go into making materials for various applications. Now, we've come up with a simpler and cheaper technology that enables better materials with atomic accuracy.”
These metals are used to make many products, from semiconductors for computer applications to display technology. We hope to see renewed interest in the more complex materials which contain these stubborn metals.
1. What does the author mean by saying “stubborn” metals?| A．The metals are complex to use. | B．It is expensive to patent the metals. |
| C．It is dangerous to create the metals. | D．The metals are hard to be made into thin films. |
| A．They increase the voltage while sputtering. |
| B．They raise the temperature to 2, 000 degrees Celsius. |
| C．They reduce the temperature to 200 degrees Celsius. |
| D．They add the atomic combinations to metals. |
| A．By making comparisons. | B．By describing process. |
| C．By giving examples. | D．By stating arguments. |
| A．New Technology to Use Metals | B．New Time of Energy Economy |
| C．New Products Made from Metals | D．New Links between Creation and Tradition |
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【推荐1】What can technology do to make your world better?Three young people are starting new businesses to answer that question.
Mateusz Mach
Eighteen-year-old Mateusz Mach was the youngest person in Poland to receive money from investors to expand his company.He started Five,a mobile messaging application,or app,for deaf people.The app lets deaf people create their own hand signs to communicate with friends.The app now has more than 10,000 deaf users.And Mach thinks there will be about 150,000 more deaf users in the U.S. next year.There are many different sign languages in various parts of the world.Mach will be working with the United Nations in New York.He says,"I love to create.And I think that the creation of things will be my passion to the end of my life."
William Zhou
William Zhou is the co-founder and leader of Chalk.com.The education software company helps teachers from the kindergarten level to 12th grade,or the end of secondary school.Zhou was born in Beijing,China,grew up in the Canadian city of Vancouver and founded his first company when he was still in high school.Zhou sold the company when he was studying computer science at Canada's University of Waterloo.But he strongly wanted to make a change in education,From his dorm room,Zhou created Chalk.It is a group of programs that supports individual teaching and learning.Based in Canada,Chalk is now used in 20,000 schools by more than 100,000 users worldwide. Zhou says building startups is a difficult process because it could last years."It's only worth it if you find something you truly care about—something you're passionate about.Otherwise,you may just end up crashing."
George Mtemaharji
George Mtemahanji was born in the African country of Tanzania and moved with his family to Italy in 2002, where he attended the Technical Institute of Alfredo Ferrari in Maranello.There he learned about renewable energy and began thinking that solar energy would be easier to use in Africa than in Europe.After graduation,he returned to Tanzania in 2014 to start his own solar energy company—Sun Sweet Solar—in partnership with his friend Manuel Rolando.He explains that he could not understand why,in a place with bright sunshine,"more than 90 percent of people had no access to electricity.So when I returned to Italy I spoke with Manuel on the huge electricity demand in Tanzania and to the possibility to open a business there."Sun Sweet Solar found early success in rural areas of Tanzania.Since then,the company has been expanding.He hopes to create jobs and help build his country in the process.He understands the process will take time."But I think we are on the right path."
1. We can infer from paragraph 2 that.| A．Mach believes helping deaf people is where his interest lies |
| B．Mach wants to attract more investment |
| C．Mach will try to make Five available to people from different countries |
| D．the number of deaf users of the app will surely increase |
| A．William Zhou founded Chalk.com with his own efforts and passion. |
| B．Chalk.com is a group of programs that helps teaching and learning through to university level. |
| C．Zhou believes building a company is hard because you may just end up in failure. |
| D．William Zhou created Chalk.com.with the purpose of improving education. |
| A．George Mtemahanji's schooling in the institute helped form his idea of starting his business |
| B．George Mtemahanji co-founded Sun Sweet Solar together with his friend Manuel Rolando |
| C．after its early success in rural areas of Tanzania,Sun Sweet Solar has been going downward |
| D．George Mtemahanji's efforts will be long-lasting and beneficial to his people and country |
【推荐2】The US scientists at the University of Vermont and Tufts University who created the first living robots say the life forms, known as xenobots, can now reproduce — and in a way not seen in plants and animals.
Formed from the stem cells of the African clawed frog (Xenopus laevis) from which it takes its name, xenobots are less than a millimeter (0.04 inches) wide. The tiny blob were first brought out in 2020 after experiments showed that they could move, work together in groups and self-heal.
“I was shocked by it,” said Michael Levin, a professor of biology and director of the Allen Discovery Center at Tufts University who was co-lead author of the new research, adding that when you free the cells from the rest of the frogs’ embryo(胚胎) and you give them a chance to figure out how to be in a new environment and a new way to reproduce.
“In that way it’s a robot but it’s also clearly an organism made from genetically unmodified frog cell.” said Josh Bongard, a computer science professor and robotics expert at the University of Vermont and lead author of the study.
Bongard said they found that the xenobots, which were initially sphere-shaped and made from around 3,000 cells, could replicate(复制). But it happened rarely and only in specific situations. The xenobots used “active replication” — a process that is known to occur at the molecular(分子的) level but has never been observed before at the scale of whole cells or organisms.
The xenobots are very early technology — think of a 1940s computer — and don’t yet have any practical applications. However, this combination of molecular biology and artificial intelligence could potentially be used in a host of tasks in the body and the environment, according to Bongard. This may include things like collecting microplastics in the oceans, inspecting root systems and regenerative medicine.
1. What can we learn from the first two paragraphs?| A．American scientists found that African clawed frog can reproduce. |
| B．Xenobots got its name because they are less than a millimeter wide. |
| C．Xenobots are an entirely new life form different from any animal or plant. |
| D．African clawed frog could move, work together in groups, self-heal and reproduce. |
| A．He was surprised by what have been found. |
| B．Xenobots could replicate only in particular circumstances. |
| C．The cells from frogs figure out a new way to move and reproduce. |
| D．Xenobots are very early technology that have a few actual applications. |
| A．Unfavorable. | B．Concerned. |
| C．Indifferent. | D．Positive. |
| A．The explanation of xenobots’ difference. |
| B．The introduction to the first living robots. |
| C．The amazement of the creation of xenobots. |
| D．The presentation of molecular active replication. |
【推荐3】AlphaGo is a computer program that plays the board game Go.
In March, 2016, the pride of humankind was crushed (粉碎) by a computer. Google’s AlphaGo defeated the South Korean grandmaster (围棋大师) Lee Sedol four games to one, as the world looked on with shock and awe (敬畏). Artificial intelligence (AI, 人工智能) had suddenly reached a new and unexpected height.
But as smart as AlphaGo is, it’s no longer the best Go “player” in the world. Google’s artificial intelligence group, DeepMind, has created the next generation of its Go-playing program, called AlphaGo Zero. The new AI program is unique in the way it learned to play Go. Instead of learning from thousands of human matches, as its predecessor (前任) did, AlphaGo Zero mastered Go in just two days without any human knowledge of the game and defeated AlphaGo by day three, reported The Guardian. It then went on to defeat AlphaGo 100 games to zero.
To learn how to play Go, AlphaGo Zero played millions of matches against itself using only the basic rules of the game to rapidly create its own knowledge of it. Like the previous version, it used “reinforcement (增强) learning to become its own teacher,” according to DeepMind’s website.
“It’s more powerful than previous approaches,” David Silver, AlphaGo’s lead researcher, told The Guardian, “because by not using human data, or human expertise in any fashion, we’ve removed the constraints (约束) of human knowledge and it is able to create knowledge itself.”
AlphaGo Zero’s approach to self-learning is a significant advancement in AI that could be applied to help solve some of the world’s biggest problems, according to a recent research report published in the journal Nature. For example, DeepMind co-founder Demis Hassabis argues that AlphaGo Zero could probably find cures for a number of serious diseases within weeks, according to The Telegraph. Indeed, the AI is now being used to study protein folding, which is connected to diseases such as Parkinson’s and Alzheimer’s.
So now that AI has exceeded (超过) the bounds of human knowledge, perhaps the question is not about what AI can learn from humans, but what humans can learn from AI. We can only wait and see.
1. What can we learn from the first three paragraphs?| A．AlphaGo defeated Lee Sedol five games to zero. |
| B．AlphaGo Zero defeated AlphaGo within one day. |
| C．AlphaGo Zero is the first program to defeat a human at Go. |
| D．AlphaGo Zero has become the new best Go player. |
| A．It can collect human knowledge automatically. |
| B．It can create knowledge without human limits. |
| C．It can become its own teacher in learning Go skills. |
| D．It can play many matches without a break. |
| A．Treating diseases. | B．Making new Go rules. |
| C．Solving math problems. | D．Creating new proteins. |
| A．Mixed. | B．Hopeful. | C．Doubtful. | D．Worried. |
【推荐1】Just like his parents and grandparents before him, Alaska teenager Carl Smith lives off the land, whether it’s catching salmon (鮭鱼) for dinner or collecting wood to keep warm in winter.
But the climate emergency is threatening the way Carl and his Yupik Eskimo family members have lived for generations, prompting (促使) the teenager to step into a role he never imagined he’d have: that of climate activist.
“I wanted to get the word out,” Carl, 18, tells People for the Earth Day special. “Nobody really knows what’s happening out here in rural Alaska.”
For Carl, home is Akiak, a small village of about 400 people who rely on the Kuskokwim River for salmon in the summer, and geese and moose (驼鹿) hunting in the spring and fall to keep their stomachs fed.
But as global temperatures rise, Alaska’s winters are getting shorter, and the permafrost (永冻土层) near Akiak is melting, causing large waves in the river that have been eroding (侵蚀) the shoreline as they crash; Carl estimates they’ve so far lost about 100 feet of land.
Carl’s concerns received national attention in 2019, when he and 15 other teenagers filed a landmark complaint with the United Nations Committee on the Rights of the Child, charging five countries with violating their rights as children by not doing enough to end the climate crisis and the threat it poses to their futures.
The complaint was spearheaded by attorney Michael Hausfeld, who says Carl stood out because climate change is directly affecting his life. “He’s experiencing it firsthand. He is watching his life slowly diminish (缩小) and disappear, M Hausfeld tells People. “Carl could become an icon for the concept of intergenerational equity (公正), which is an obligation of states to secure a living planet for the next generations.”
Carl traveled to New York for the Human Rights Day Summit, where he met fellow activists like Greta Thunberg and Alexandria Villasenor, who are also part of the complaint.
“When I heard the stories from people around the world, I felt like I was with them,” he says. “We’re experiencing different things, but in a way, it’s all the same. I just felt connected to them in some way.”
“I’m going to keep telling everyone that climate’s coming, climate’s changing, and it’s happening everywhere in the world,” he says. “If we don’t do anything about it, we won’t have a home to live in. I just hope everyone listens.”
1. What does the underlined phrase “get the word out” in paragraph 3 probably mean?| A．Let people know about something. |
| B．Conduct research on something. |
| C．Stop something from happening. |
| D．Go out for an adventure. |
| A．Five countries ignored the climate crisis. |
| B．The Eskimos lived on what nature gave them. |
| C．The Eskimos’ overuse of natural resources caused damages. |
| D．Some countries were charged with violating international obligations. |
| A．The population is decreasing. |
| B．Some species are going extinct. |
| C．More and more land is being lost. |
| D．Forests are being destroyed. |
| A．Doubtful. | B．Critical. | C．Supportive. | D．Worried. |
| A．To call attention to the climate crisis. |
| B．To protect children from violence. |
| C．To voice support for Eskimo children. |
| D．To raise money for his hometown. |
| A．Optimistic. | B．Generous. | C．Modest. | D．Responsible. |
【推荐2】Set 40 kilometers northeast of the city of Ambatondrazaka, Madagascar, the Zahamena National Park has overall land coverage of 643 square kilometers, but only about 420 square kilometers is open to the public. It receives an average rainfall level of around 6 feet every year and experiences frequent rain showers even during the dry season between April and October. And elevations (海拔) inside the park range from 250 to 1,560 meters, which has resulted in a diversity (多样性) of climates.
One really interesting thing about the Zahamena National Park is its unique highland landform (高地地貌). The development of several ecosystems that all together exist within its area greatly depends on it. And this is also the reason why the types of wildlife living in one area of its wide range are different in another, which makes it quite exciting to explore.
This protected region’s main area is divided into two parts: the eastern and western areas, with a separate piece of ground in the middle where many small villages are located. Zahamena means “red trees”, which suggests a tree species scientifically called Diatum unifoliatum. It lives only in Zahamena and is characterized by its typically deep reddish-orange color.
Established as a strict natural highland habitat for nature conservation (保护) in 1927, the Zahamena National Park was officially awarded the honorary title of national park in 1997 and was finally opened to the public. Due to its amazing landform and unique local biodiversity, this national park was later listed as a key part of the Rainforests of the Atsinanana in 2007.
Unluckily, there are no hotels or restaurants around the national park. So Zahamena is not an easy rainforest—this national park needs people with a high level of fitness and people with low requirements concerning accommodations. Everyone who is not discouraged by this will be able to expect an amazing rainforest experience in a location which has a small number of tourists.
1. What do we know about the Zahamena National Park?| A．It is hard to reach due to conservation rules. |
| B．It has changeable weather all year round. |
| C．It has a great difference in elevations. |
| D．It is famous for its traditional villages. |
| A．The complete food chain of wildlife there. |
| B．The wet weather condition there. |
| C．The conservation efforts there. |
| D．The special landform there. |
| A．A cultural belief. | B．A local tree species. |
| C．The unique geography. | D．The local village group. |
| A．The tough condition of Zahamena. | B．People’s high level of fitness. |
| C．Its geographical location. | D．The diversity of climates. |
【推荐3】Vaping (吸电子烟) is becoming booming these days. The basic idea behind this is simple: vaping is a way of taking in nicotine (and other substances) that is far safer than smoking, because vapes produce far lower levels of the most harmful chemicals than cigarettes, as the World Health Organization notes. But there are several obvious issues with this.
Firstly, there is enormous variability in vaping products and devices. The market is largely unregulated, which means the term “vape” covers everything from solid, reliable devices to something that will explode when you put it in your mouth.
Switching from smoking to vaping is probably good for your health, but the epidemiological (流行病学的) evidence shows that most people become what’s known as “dual users” who both vape and smoke in differing amounts. Because of their different smoking regimes (养生法，方法), the evidence on whether dual use is more beneficial than just smoking is unclear.
Vaping is obviously worse for your health than quitting completely. In an experimental study led by Prof David Thickett in the University of Birmingham, the researchers designed a mechanical procedure to mimic (模拟) vaping in the laboratory, using lung tissue samples provided by eight nonsmokers. They found that vapor (蒸汽，雾) of vaping damaged the activity of alveolar macrophages (肺泡巨噬细胞), cells that remove potentially damaging dust particles and bacteria. They said some of the effects were similar to those seen in regular smokers and people with chronic lung disease. Moreover, there’s pretty good evidence that vaping nicotine products is habit-forming and addictive, and there’s a great deal of concern among epidemiologists that in young people vaping can lead to smoking, which is obviously a bad thing.
1. Which of the following is the most harmful to our health according to most people?| A．Smoking. | B．Vaping. |
| C．Dual use of both vaping and smoking. | D．Nonsmoking. |
| A．Vaping does less harm to health than smoking. | B．Vaping can make one addicted to it. |
| C．Vaping is a bad thing. | D．Vaping is safer than smoking. |
| A．travel | B．sports | C．health | D．music |
| A．Supportive. | B．Indifferent. | C．Favorable. | D．Disapproving. |
