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Mya Le Thai is a scientist studying at the University of California. She recently discovered a process that may result in batteries that last forever. Thai said she had been frustrated that the batteries for her wireless devices degrade(退化). Over time, they fail to charge fully. She decided to do something about that problem.
At first, she and her team thought about inventing a new battery. But as they experimented, Thai discovered something that might permit lithium-ion batteries(锂电池) to last forever. Lithium-ion batteries power most wireless devices. Over time, the batteries lose the ability to hold a charge. One of the reasons lithium-ion batteries degrade is their use of nanowires(纳米线) to carry electricity. Nanowires are extremely thin. Nanowires are extremely efficient carriers of electricity, which makes them useful in batteries. But Thai said their thinness also makes them weak. “Nanowires break over time,” she said. “That’s why they lose capacity.”
But, Thai had a theory: The nanowires might last longer if covered with a gel(凝胶). She and the team tested her theory. The team tried many coverings for the wires. PMMA was one of them. The PMMA coated nanowires showed no evidence of damage. The results suggest that batteries could last forever, without losing charging ability. Thai hopes to continue her research to understand why this gel works so well and to see if any other gel could create better results.
Mya Le Thai told VOA she is enjoying the publicity about her discovery. She said she never expected her research to get media coverage. “It’s kind of cool,” she said. “I’m really glad people are showing interest in my work and not just in the work itself, but also in technology and energy.”
1.Why did Mya Le Thai make up her mind to settle the problem about her wireless devices degrade?
A.Because her wireless devices couldn’t work at all.
B.Because she discovered a new kind of battery.
C.Because the batteries for her wireless devices couldn’t last long.
D.Because she wanted to show her new research.
2.What prevents lithium-ion batteries from lasting forever?
A.PMMA. B.Nanowires.
C.Electricity. D.Power.
3.How can the scientist make the nanowires last longer?
A.By using a gel to cover them. B.By cutting them shorter.
C.By making them longer. D.By using a gel to make wire.
4.What kind of person is Mya Le Thai?
A.Generous and wise. B.Honest and wise.
C.Honest and hard-working. D.Modest and creative.
难度: 中等查看答案及解析
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What are some of your favorite memories of the University?
In preparation for each fall’s 50th reunion members of the milestone class are asked to recall campus memories for an annual Memory Book.
Here’s a small selection of some memories from the Class of 1969.
Phyllis Jo Baunach
“…I cannot forget the endless hours studying, researching, and learning in the middle of the musty books in the stacks. We did everything by hand! But the joys of ideas coming to life and understanding thorny concepts are priceless.
Additionally, I cannot forget the joyful hours of Co-Kast rehearsals for student-written-and-directed plays, and the thrill of audiences’ responses to our efforts. Nor will I ever forget taking voice lessons at the Eastman School of Music. This course gave me confidence to try new musical approaches and to think on my feet.”
Paul Boehm
“…many sweet and lasting memories-five feet of deep snow, getting stranded on the Thruway, music at Hylie Morris’s Alley, and, of course, I met my wife of 48 years, Eller Blazer Boehm from the Class of 1972, when she was a freshman and I was a senior. As a five-year chemical engineering major, I had one elective to spare, and Ellen said, ‘How about oceanography?’ So, I enrolled in oceanography with Dr. Taro Takahashi (the famous climate scientist), which awakened my environmental juices, and changed my professional direction.”
Farel Vella McClure
“…I truly loved my four undergraduate years at the University of Rochester. In fact. I loved it so much that I stayed an extra year to get a master’s degree! I was very fortunate to have been totally immersed in student life on campus. My memories include campaigning and winning a seat on the student government during my freshman year. Other memories include the Susan B. Anthony banquet, and sleeping in the comfy chairs in the library. I was also privileged to be selected as a student representative on the design team for the new Wilson Commons. I. M. Pei, the famous architect who designed the Louvre Pyramid, was the architect for Wilson Commons. We even visited his offices in New York to see the ‘master’ at work.”
1.According to the passage, Paul Boehm .
A.married Ellen Blazer in 1972
B.disliked his major in university
C.became a famous climate scientist later
D.discovered his interest in environmental science
2.What does the underlined word “comfy” in the last paragraph mean?
A.Common. B.Column.
C.Combining. D.Comfortable.
3.The three people all talked about .
A.their beloved professors
B.their great friendship
C.their learning experiences
D.their beautiful campus
难度: 简单查看答案及解析
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This little South American Magellanic penguin swims 5,000 miles, to a beach in Brazil, every year in order to be reunited with the man who saved its life. It sounds like something out of a fairy tale, but it’s true!
71-year-old retired brick worker Joao, who lives in an island village just outside Rio de Janeiro, Brazil, found the small Magellanic penguin lying on rocks at his local beach in 2011. The penguin was covered in oil and running out of time fast. Joao rescued the penguin, naming it Din, cleaned the oil off its feathers and fed him a daily diet of fish to rebuild its strength. After a week of recovery, Joao attempted to release the penguin back into the wild. However, Din had already formed a family bond with his rescuer and wouldn’t leave.
“He stayed with me for 11 months and then, just after he changed his coat with new feathers, he disappeared,” Joao recalls. “I love the penguin like it’s my own child and I believe the penguin loves me,” Joao told Globo TV. “No one else is allowed to touch him. He pecks (啄) them if they do. He lies on my lap, lets me give him showers, and allows me to feed him.”
Professor Krajewski, a biologist who interviewed the fisherman for Globo TV, told The Independent: “I have never seen anything like this before. I think the penguin believes Joao is part of his family and probably a penguin as well.”
However, environmentalists warn that, while hundreds of the Magellanic species are known to naturally migrate (迁徙) thousands of miles north in search of food, there has been a worrying rise in the phenomenon of oceanic creatures washing up on Brazil’s beaches. Professor David Zee from Rio de Janeiro’s State University, said the increase is due in part to global climatic changes. Professor Zee added that sea animals face increased danger from leaked tanker oil.
Luckily the ending for Joao and Din has been a happy one, even though it is illegal in Brazil to keep wild animals as pets.
Professor Krajewski said: “Professionals who work with animals try to avoid relationships like this occurring so they are able to reintroduce the animal into the wild. But in this single case the authorities allowed Din to stay with Joao because of his kindness.”
1.Every year Din swims a long distance to a beach in Brazil to ______.
A.avoid being killed B.meet his rescuer
C.escape from ocean currents D.find much more fish
2.When Din was found in 2011 ______.
A.he was dying B.he was running on the beach
C.he was resting on a rock D.he was cleaning oil off his feathers
3.What can we learn about Joao from the passage?
A.He is not allowed to keep the penguin as a pet by the authorities.
B.He overprotects the penguin by keeping him away from others.
C.His contact with the penguin is encouraged by professionals.
D.His kindness wins the penguin’s trust.
4.The story in the passage mainly shows ______.
A.the environmental impact on wildlife
B.the love between humans and wildlife
C.the tendency of wildlife to bond with humans
D.the protection of threatened wildlife by mankind
难度: 中等查看答案及解析
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Most people aren’t good at creative problem solving for two reasons: (1) They are not trained in how to be creative. (2) They don’t understand group strength well enough to harness (驾驭) their power to maximize group creativity.
A key element of creativity is applying existing knowledge to a new problem. The more people getting involved in solving it, the more knowledge there is to work on it. Unfortunately, research shows that the traditional brainstorming methods fail to achieve that goal. When groups get together to exchange ideas, they actually come up with fewer ideas overall than if they each had worked alone.
To fix this problem, you should consider the two stages of group problem-solving: divergence (分散) and convergence (集中). Divergence happens when the group considers as many different potential solutions as possible. Convergence happens when the various proposed solutions are evaluated and reduced to a smaller set of candidate solutions to the current problem.
The essential principle of group creativity is that individuals working alone diverge, whereas group members working together converge. In groups, once a member states a potential solution, that makes others think about the problem similarly. That is why groups working together diverge less than individuals working alone.
Therefore, be aware of when to diverge and when to converge. For example, early in the problem-solving process, have group members work alone to write down statements describing the problem. Then get them back to discuss their descriptions. The group discussion will lead everyone to accept one or a small number of these statements to work on — this is healthy convergence.
When starting to generate solutions, you again want divergence. Have people work alone to start. Then collect people’s initial ideas and send them around to others and allow the divergence to continue as everyone individually builds on the ideas of other members.
Finally, let the group discuss the resulting ideas. This discussion will gradually lead the group to converge on a small number of candidate solutions.
This simple method works effectively, because it respects what individuals and groups do best.
1.According to Para. 4, when a member presents an idea, others tend to_____.
A.think the other way round
B.follow his way of thinking
C.be more confident in their own ideas
D.be less willing to share their own ideas
2.What should group members first do early in the problem-solving process?
A.Discuss the problem.
B.Simplify the problem.
C.Put down group statements together.
D.Write down their individual descriptions.
3.How can each group member make changes to his initial solution?
A.By adding in collected evidence.
B.By reorganizing his own words.
C.By drawing on others’ ideas.
D.By making his statement briefer.
4.What is the author’s purpose in writing the passage?
A.To advocate a way to make group thinking more effective.
B.To demonstrate the difficulty in organizing group thinking.
C.To highlight the differences between divergence and convergence.
D.To show the advantage of group thinking over individual thinking.
难度: 中等查看答案及解析