A Battery's Nightmare Portable electronics that can be carried about easily are only as good as their batteries and, let's face it, batteries aren't very good, especially when compared with, say, petrol, which packs 100 times a battery's energy into an equal space. That's why a large group of mechanical engineers (centered at the Massachusetts Institute of Technology, but with partners at other universities and companies) are hard at work in an effort to replace batteries with a tiny engine that runs on fuel. Imagine a battery-free life! When the fuel runs out in your mobile phone, you just fill up and go. The engine---about the size of a ten-cent coin---starts with a combustion chamber that burns hydrogen. Its tiny parts are etched onto silicon wafers in the same manner that computer parts are etched onto integrated circuits . The first engine is made up of five wafers. And since these wafers could be produced in much the same way as computer chips, they could probably be produced quite cheaply. But the _ in all this nice detail is efficiency. Tiny engine parts don't always behave like the bigger parts of the first engine. Something between the parts can slow down the works, according to Columbia University Professor LucFrechette, one of the engine's designers. Extreme heat from the combustion chamber is also a problem, often leaking to other parts of the engine. The scientists' goal is to create an engine that will operate 10 times better than batteries operate. Frechette says that a complete system, with all parts in place and working, will be set up in the next couple of years, but commercial models aren't likely until at least the end of the next ten years. According to the passage, the title suggests that _ . A) batteries should be greatly improved B) petrol will be used instead of batteries C) the time of batteries will be gone forever D) pollution problems caused by batteries must be solved
C
(Question)
One baby born with a defective windpipe now has hope of breathing normally thanks to 3-D printing technology, NPR reported. Garrett Peterson, now 18 months old, was born with tracheomalacia , leaving him unable to breathe. The condition terrified his parents, who turned to specialist Dr. Glenn Green at the University of Michigan for a possible treatment. Along with Scott Hollister, a biomedical engineer who runs the university's 3-D printing lab, Green designed a device that can hold open Garrett's windpipe until it's strong enough to function independently. After taking a CT scan of Garrett's windpipe to make a replica of it, they made the "splint" with a 3-D printer. "It's like a protective shell that goes on the outside of the windpipe, and it allows the windpipe to be tacked to the inside of that shell to open it up directly," Green told NPR. On January 31, Garrett had his surgery. Surgeon Dr. Richard Ohye opened up Garrett's chest and saw that his windpipe had completely collapsed and one of his lungs was completely white -- a condition Ohye had only seen in dead bodies. After eight hours of surgery and careful placement of a splint on either side of Garrett's windpipe, it was time for the big test: What would happen when they let air flow through the windpipe into Garrett's lungs? Though he still remains in the hospital, Garrett has gotten stronger and needs less assistance breathing in the weeks since his surgery. His parents are overjoyed, saying he's starting to act more interactive and alert. As Garrett grows, the splint will expand and eventually dissolve in his body as his own windpipe strengthens enough to work independently. 3-D printing technology has allowed doctors to help patients in ways that they hope will continue to grow. "We're talking about taking something like dust and converting it into body parts," Green said. "And we're able to do things that were never possible before." We can learn from the passage that _ . A) Garrett is out of hospital with the help of 3-D printing technology. B) The splint will exist in Garrett's body for ever. C) It is difficult to operate the 3-D printer. D) Garrett's condition is critical.
(Answer)
D
Ques: The 2016 Rio Olympic Games have come to an end. Without doubt, many Chinese sports fans sat in front of the TV and cheered our athletes on, hoping that they would get as many gold medals as possible. But sometimes our desire for gold medals can result in the sadness of failure. When Liu Xiang, China's track hero, pulled out of the Beijing Olympics due to injury, he greatly disappointed many Chinese sports fans. But things are different now. In the 2016 Rio Olympic Games, we saw a healthier and more _ Chinese attitude toward the sportspeople, fully in line with the Olympic spirit. China didn't win any gold medals on the first day. But, instead of criticizing the athletes who failed to finish on top of the podium , the majority of fans were happy with their efforts. "Reacting in the right way when an athlete misses out on gold shows the maturity of a person, and is also a challenge for a country to face up to in the process of development," commented CRI. Swimmer Fu Yuanhui won fans' hearts, even if she only won a bronze medal in the 100m backstroke final. Her fans on her Sina Weibo micro blog have increased 100,000 to over 6 million. Many sports fans appreciated her straightforward character and attitude toward competition. "The warm support from Internet users shows that public attitude toward competitive sport and the Olympics have gotten to a higher level," said an article in the People's Daily. From passage 2, what can we know about Liu Xiang? A) He is still a famous athlete. B) He didn't complete his event in the Beijing Olympics. C) The audience desired him little. D) He was required to give up the competition.
Ans: B
Question: Opened in 1883, the Brooklyn Bridge was the first longspan bridge to carry motor traffic, and it quickly became the model for the great suspension bridges of the following century. Spanning New York's East River, it provided the first traffic artery between Manhattan Island and Brooklyn. Before that, the only transportation was by ferries, which were slow and could be dangerous in winter. The construction of a bridge over the EastRiver had been discussed since the early 19th century, but the outbreak of the Civil War in 1861 _ all consideration of the project. When the war ended in 1865, the bridge became an important issue once more. In 1867, the New York State passed an act setting up the New York Bridge Company for the purpose of constructing a bridge between Manhattan Island and Brooklyn. John Augustus Roebling was chosen to design the bridge. Born in Germany in 1806, he held aggressive views as a student and was listed by the German police as a dangerous figure. He emigrated to America in 1830 to escape political discrimination. Roebling proposed a bridge with a span of 1,500 feet (465 m), with two towers in the East River serving as the main piers. The bridge that was actually built is longer--1,597 feet (486 m), the longest suspension bridge at that time. Which of the following is TRUE about the Brooklyn Bridge? A) It was built in 1865. B) It is shorter than originally planned. C) It was first proposed after the Civil War. D) It was built by the New York Bridge Company.
Answer:
D