Train Floating On Air
A train that floats on air? It's not magic—it's magnets (磁). And it's close to reality. In Virginia USA the fall of 2002, a train with no wheels traveled on air and carried college students across their campus. In Japan, a whisper-quiet railway engine hovered and raced at 350 miles per hour using magnets and electricity as the power. And in China, a magnet train line linked Shanghai with nearby Pudong Airport.
These trains use magnetic levitation (悬浮) technology, “maglev” for short. They use the same rules as the magnets you pick up at home or school: opposite poles of magnets attract each other, and like poles repel each other.
How does it work?
Powerful magnets on the bottom of the train repel magnets on the track, which is actually just a magnet-filled guiding way. With a magnetic field of sufficient force, the train will go hovering on air, which seemed impossible to us in the past.
When an electrical current is sent through the track, the train moves. Turn the current backwards and the train slows down.
Maglev doesn't rely on the friction (摩擦力) of wheels on track, so it can climb a much steeper hill than a traditional train. And it can travel easily in snow and ice, something that could bring normal trains to a screaming stop.
1. This passage is about ________.| A．maglev | B．magnets | C．levitation | D．electricity |
| A． | B． | C． | D． |
| A．A magnet filled guiding way is formed inside a maglev train. |
| B．Instead of electricity magnets are used as the power of n maglev. |
| C．Maglev trains can climb hills with the help of magnet wheels. |
| D．Electric currents decide the movements of a maglev train. |
| A．A maglev train can climb mountains without power while an ordinary one can't. |
| B．A maglev train can travel in college campus while an ordinary train is not allowed. |
| C．Travelling without a track, a maglev train is safer and smoother than an ordinary one. |
| D．Floating on a track, a maglev train is faster, quieter than an ordinary railway train. |
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【推荐1】There's a battle storming in the streets of America. Anyone who regularly rides a bicycle knows all about this. Some motorists shout at two-wheeled travelers, who slow traffic. A few will do even worse.
The New York Times reports that incidents of aggression toward bicycle riders appear to be growing. Even though actually every state allows bicyclists the same right as motorists to use the streets, many drivers still refuse to accept this. They view themselves as Kings of the Road --- an impression that has been strongly built by the transportation planning profession, which has designed our cities as if people didn't exist outside of their cars.
But a big new idea to settle this conflict and improve life in the streets for everyone is now taking root among community activists, urban planners and traffic engineers.
“Too many of our streets are designed only for speeding cars, They're unsafe for people on foot or bike. Now, in communities across the country, a movement is growing to complete the streets. States, cities and towns are asking their planners, engineers and designers to build road networks that welcome all citizens," declares the website of a new organization promoting this idea, "Complete the Streets", the best idea to hit our communities since pizza, or even the bicycle itself.
My home of Minneapolis is one of the biking capitals of America. But it hasn't always been that way. When I moved here many years ago, I was shocked at the strong hostility directed toward me whenever I dared ride my bike down the street. Drivers would suddenly turn in my direction, and then laugh as they nearly knocked me onto the ground.
As the number of bikes on Minneapolis streets has grown, people have become much more comfortable sharing the road with two-wheelers. Indeed, I get the impression that most motorists now envy rather than hate me, and can't wait to get home where they can jump on their own bikes. This will happen everywhere as more and more Americans discover biking as a great way to get around, save money, lose weight, protect the planet and have fun.
1. Who cause the traffic problem according to the motorists?| A．Bicycle riders. | B．Urban planners. |
| C．Traffic engineers. | D．Community activists. |
| A．weight losing | B．city planning |
| C．money saving | D．global warming |
| A．Relieving traffic jams. | B．Promoting walking and bicycling. |
| C．Building more road networks. | D．Assessing the impact of the conflict. |
| A．To present a problem. | B．To praise the bicyclists. |
| C．To describe a change. | D．To blame the car riders. |
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| A．in London. | B．around the UK. |
| C．all over Europe. | D．around the world. |
| A．Put them into containers. |
| B．Send them to the company. |
| C．Get them back by yourself. |
| D．Pay ￡12.5 per week for each box. |
| A．￡498. | B．￡570. | C．￡769. | D．￡869. |
【推荐3】Considered one of Europe’s two “bicycle capitals” along with Amsterdam, Copenhagen(哥本哈根) counts more bicycles than people and cycling is so popular that its numerous bike paths can become crowded. Two-wheeler traffic jams are especially regular on the main Noerrebrogade road used by around 36,000 cyclists a day. “You have to elbow your way in to go forward and some cyclists aren’t always thoughtful,” complains 22-year-old university student Lea Bresell.
The creation of bike highways “comes right on time”, says Danish Cyclist Federation Spokesman Frits Bredal. “Copenhagen’s roads are overloaded with people who want to ride their bicycles in all kinds of weather,” he says. “If in the 1960s Danes viewed the car as the symbol of freedom, the bicycles have supposed that role today,” Bredal says. “It’s a mode of transportation used by all social classes, even politicians ride bikes,” he says.
It is on crowded Noerrebrogade—the busiest bicycle street in Europe, according to the cyclist association—that city planners have decided to build the first of Copenhagen’s environmentally friendly roads. The jammed bike paths will be widened up to four metres on either side of the road, which itself will be reserved for bikes only. The idea is to make Noerrebrogade “Europe’s great cycling street”, says Andreas Roehl, Copenhagen government’s bicycle program manager who is also known as “Mr. Bike”.
But Roehl is not content with making life easier for Copenhagen’s inner-city cyclists: He wants to get suburbanites(郊区居民) out of their cars and onto two wheels as well. His goal is to hike the percentage of suburban commuters cycling to and from the city from the 37 percent it is today to 50 percent by 2015.
1. Why does Copenhagen plan to build the first bike highway?| A．Because bike highways are environmentally friendly. |
| B．Because it’s a part of the city’s development program. |
| C．Because the inner-city commuters urge that it should be built. |
| D．Because too many bicycles cause the paths to be crowded. |
| A．Because the price of petrol has been going up all the time. |
| B．Because the bicycle is viewed as the symbol of freedom nowadays. |
| C．Because it’s hard for people to find parking space in crowded streets. |
| D．Because politicians ride bikes and commuters enjoy following them. |
| A．fashion | B．improvement |
| C．reform | D．law |
| A．The former jammed bike paths will be widened. |
| B．Noerrebrogade is to be made “Europe’s great cycling street”. |
| C．All commuters will be pushed to leave their cars at home. |
| D．More suburbanites will be got out of their cars and onto two wheels. |
【推荐1】A team of researchers led by engineers from Penn State University has created the first material that heals itself in the presence of water, according to a study published in Scientific Reports. The material, inspired by squid (鱿鱼)teeth, could be used to repair instruments in water-filled environments that are difficult to access, such as the human body, or the bottom of the sea.
The researchers had been studying squids' ring teeth, which are uniquely strong and can change state from liquid to solid in the presence of water. After testing ring teeth samples from several species of squid found all over the world, the researchers uncovered the genetic code for the proteins (蛋白质)that allow the teeth to heal themselves when broken. They then changed the genetic structure of bacteria to produce the proteins so they could conduct more tests.
The researchers then made the proteins into a rubbery plastic by mixing them with a solvent (溶 剂)and letting the solvent change into a gas. The resulting material combines a soft, shapeless part of the protein that gives the plastic its self-healing characteristics and a more structured sheet of amino acids(氨基酸)that give it a solid structure.
To test the material's strength, the researchers cut it, and then put the two pieces back together with a drop of water. They found that the material healed best at 113 degrees Fahrenheit, a little warmer than the temperature of the human body, and with slight pressure from a metal tool. The material was just as strong, and able to hold the same amount of weight, before and after it was cut.
Material that heals itself in the presence of water could expand the usability of biomedical implants (移植). Of course, this material is nowhere near ready for that application, and the researchers didn't test whether the constant presence of water degrades (降低)the plastic's ability to heal itself. The researchers next plan to study how their technology could help heal wounds.
1. According to paragraph 3, the rubbery plastic become self-healing in combination with.| A．amino acids | B．another kind of rubber |
| C．a mixture of gases | D．some protein |
| A．was fit for human body |
| B．would melt at high temperatures |
| C．could be connected with the metal |
| D．would recover its original strength after healing itself |
| A．Positive. | B．Objective. | C．Doubtful. | D．Critical. |
| A．A kind of self-healing teeth was made from squids' ring teeth. |
| B．The genetic code of squids' special teeth has been uncovered. |
| C．Super-strong material inspired by squid teeth is self-healing. |
| D．A special rubbery plastic is used to replace squids' teeth. |
【推荐2】Smart and highly sensitive (灵敏的), a new soft sensor developed by UBC (University of British Columbia) and Honda researchers opens the door to a wide range of applications in robotics and prosthetics (假肢).
When applied to the surface of prosthetic or robotic arms, the sensor skin provides touch sensitivity and flexibility, making it possible for difficult tasks to be completed by machines, such as picking up a piece of soft fruit. The sensor is also soft to the touch, like human skin, which helps make human interactions safer and more lifelike.
“Our sensor uses weak electric fields to sense objects, even at a distance, much as touchscreens do. But unlike touchscreens, this sensor is soft and can detect (检测) forces into and along its surface,” explained Dr. John Madden, senior study author and a professor of electrical and computer engineering who leads the Advanced Materials and Process Engineering Laboratory at UBC.
The UBC team developed the technology in cooperation with Frontier Robotics, Honda’s research institute. Honda has been innovating in humanoid robotics since the 1980s, and developed the well-known ASIMO (Advanced Step in Innovative Mobility) robot. It has also developed devices to assist walking and the emerging Honda Avatar Robot.
“Dr. Madden’s lab has significant expertise in flexible sensors and we’re happy to cooperate with this team in developing touch sensors that can be applied to robots.” said Mr. Ishizaki Ryusuke, one of the study’s lead authors and chief engineer at Frontier Robotics.
Dr. Madden said. “Human skin has a hundred times more sensing point s on a fingertip than our technology does, making it easier to light a match or sew. As sensors continue to develop to be more skin-like, and can also detect temperature and even damage, there is a need for robots to be smarter about which sensors to pay attention to and how to respond. Developments in sensors and artificial intelligence will need to go hand in hand.”
1. What do we know about the new sensor?| A．Its surface feels soft. | B．It is far from sensitive. |
| C．Its interaction with humans seems unsafe. | D．It is unable to pick up a piece of fruit. |
| A．Its types. | B．Its structures. |
| C．Its advantages. | D．Its directions for use. |
| A．Doubtful. | B．Positive. |
| C．Unconcerned. | D．Unclear. |
| A．Human skin is easily hurt. | B．A fingertip has few sensing points. |
| C．Sensors can light matches easily. | D．Robots need further improvement. |
【推荐3】Even in the most speculative reaches of science fiction, there is no escaping humanity’s dependence on liquid water. The residents of the desert world Arrakis, accessible to anyone with a copy of Frank Herbert’s novel “Dune”, use windtraps to steal precious liquid from the air.
Collecting water from the air is nothing new. The Inca, who are widely thought to have invented the technique,placed buckets under trees to collect the condensation from heavy fog drifting in off the sea. People dwelling in the arid mountains of Oman have long built cisterns under trees for the same reason.
Instead of using leaves as condensation traps, however, which drip over an impractically large area, modern traps instead consist of sheets of very fine polymer mesh. As fog flows through the sheets, tiny droplets of water stick to the polymer fibres. These droplets grow until gravity pulls them into a compact trough and, thence, a reservoir. While collectors vary in size, a 40-metres-square collector in a reasonably foggy area yields around 200 litres a day, enough to supply 60 people with drinking water.
A team led by Dr Stachewicz found that the sheet could be made even more productive by changing the way in which its polymer threads were manufactured. Dr Stachewicz theorized that careful manufacture via a process known as electrospinning could lend the sheet a slight electrical charge that would prove attractive to water droplets in fog. In experiments conducted in 2021 she and a team of colleagues found that such sheets yielded 50%more water.
This past August, Dr Stachewicz reported further improvements by adding TiO₂ to the mesh. Previous work had shown that TiO₂ could be intensely attractive to water upon exposure to ultraviolet light-a hindrance under extremely foggy conditions, as water would stick to the mesh rather than trickle into the cistern. When fog was light, however, Dr Stachewicz and Mr Parisi found that a TiO₂-enhanced mesh became 30% more effective. Her fog collectors are now being used at sites on three continents.
This technology suggests a brighter future is possible. Areas so dry as to have gone without rainfall since modern records began may one day yield enough water to sustain settlement. And not just on a fictional planet.
1. Why did the writer mention a copy of Frank Herber’s novel?| A．Because the characters also get water from the air. |
| B．Because people in the novel also live without water. |
| C．Because it sets an opposite example of getting water. |
| D．Because the engineers got the inspiration of inventing traps from the novel. |
| A．Water from leaves drips over a large area. |
| B．Gravity pulls the droplets into a container. |
| C．Fog streams through sheets of polymer mesh and adhere to it. |
| D．Fog flows through sheets of polymer mesh and the polymer fibres. |
| A．It purifies water droplets. |
| B．It appeals to water droplets. |
| C．It fights against water droplets. |
| D．It blocks the fog from flowing. |
| A．How to capture water from the air. |
| B．A solution to relieving water stress. |
| C．Getting water from the air with different methods. |
| D．Using windtraps to steal precious liquid from the air. |
【推荐1】Health experts have long known that vitamin D is important healthy bones and teeth. It may also help to protect the body against disease such as diabetes and cancer. And now, researchers say vitamin D might help fight brain diseases called dementia (痴呆).
Dementia is a brain disease that damages thinking and memory processes, which scientists call “cognitive (认知) abilities” Dementia is difficult to treat. Taking care of someone who has dementia is extremely demanding. And the disease is very frightening to sufferers. Chris Roberts suffers from dementia He says the worst part of living with this disease was getting lost while driving. “The worst thing that I found was getting lost in the car, not just forgetting where I was going-I wouldn't know where I was.” More than 47 million people around the world suffer from dementia. The World Health Organization reports that 60 percent of them live in low-and-middle-income countries.
We get vitamin D from some foods like nuts, some peas and fatty fish. We also get vitamin D from the sun. But that is not dependable. In some parts of the world, there is not enough sunlight to provide enough vitamin D. Also, sunblock prevents the vitamin from entering the body. To add to the problem, the skin's ability to process vitamin D weakens as a person ages.
Researchers at Rutgers University in New Jersey are exploring the relationship between vitamin D and dementia. The team recently measured vitamin D levels and cognitive ability in older people. Nutritional science professor Joshua Miller led the team. He said cognitive abilities differed among the study subjects. He said tests showed that about 60 percent of the group was low in vitamin D.
1. Which of the following is true about vitamin D?| A．Vitamin D can decrease people's risk of heart diseases. |
| B．Vitamin D helps the body fight against cancer. |
| C．Vitamin D is mainly obtained from the sun. |
| D．The need for Vitamin D decreases as people age. |
| A．Boring but rewarding. | B．Disturbing and frightening. |
| C．Disgusting and stressful. | D．Hard and tiresome. |
| A．How vitamin D affects people's health. |
| B．Where people get vitamin D. |
| C．Whether sunlight can produce vitamin. |
| D．Why people’s age influences the production of vitamin D. |
| A．Travel handbook. | B．Food magazine. |
| C．Science journal. | D．Commercial advertisement. |
【推荐2】Automatic dishwashers have been around for more than 100 years. It started in 1886 with Josephine Cochrane, a woman in Shelbyville, Illinois. She was a rich woman who could afford servants to wash her dishes, so she really didn’t mind the work. What she did mind was that her servants broke the dishes. She hosted quite a few dinner parties, and after every party the servants broke more of her expensive dishes.
Finally, Cochrane took action. First, she measured her dishes and bent wire into racks to hold them. Next, she put the racks on a wheel in a large copper boiler. Then, the boiler sprayed hot, soapy water on the dishes as a motor turned the wheel. After a hot water rinse(冲洗), the dishes were clean!
Josephine Cochrane’s friends were impressed with the machine and asked her to build more. After that, word got out fast. Soon hotel and restaurant owners who didn’t like broken dishes also were interested. Cochrane then knew that she had a wonderful machine, so she received a patent from the government, which said that only the inventor can make money from an invention. Then in 1893 Chicago held a World’s Fair where inventions from all over the world were shown. Cochrane’s labor-saving machine was a big hit. Her dishwasher won the highest award.
Cochrane’s company came out with a smaller machine in 1914. It was supposed to be for the ordinary home, but it wasn’t an immediate success. Many homes couldn’t produce the extremely hot water it needed. Also, in most homes, dishwashing wasn’t considered very difficult compared to most other housework. In fact some people liked to relax at the sink after a hard day! Sales of the home model finally picked up in the 1950s when people had more money and wanted to have more time to enjoy themselves. Now many homes have electric dishwashers that aren’t very different from the one Josephine Cochrane invented more than 100 years ago.
1. Why did Josephine Cochrane invent the dishwasher?| A．To reduce the number of servants. |
| B．To avoid possible damage to the dishes. |
| C．To host more dinner parties. |
| D．To make the dishes cleaner. |
| A．The machine wasn’t as efficient as described. |
| B．Josephine Cochrane could no longer keep it a secret. |
| C．Josephine’s friends soon began to talk about the new machine. |
| D．The invention drew immediate attention of the public. |
| A．people’s living conditions improved |
| B．hot water was not needed |
| C．housework became easier |
| D．people had more relaxing jobs |
| A．cost less money |
| B．are quite different |
| C．wash many other things |
| D．are much the same |
【推荐3】We’ve been told since we were children that “It’s good to share”. Parents and teachers keep reminding us to share toys and books. When we grow up, we share photos, life stories and opinions with people around us and with those we don’t know via social media. Psychologists believe that the behavior of sharing is beneficial to setting up positive emotional connection.
Today, the action of sharing takes on extra meaning. It has spread to almost every aspect of our lives. We are using technology to reduce the money that we spend on goods and services, or to make money out of those that we don’t use ourselves at all. These differ from car shares to home shares, and even to pet shares. The sharing economy is creating new ways of thinking and is providing services to people when and where they want them.
This popular ways of sharing is a response to our increasing demand for quality goods and services at competitive prices, all delivered at the click of a button. Whether we’re a lender or a borrower, it’s a win-win situation. What’s more, sharing encourages us to reuse items, thereby cutting down on waste. And set-ups such as bike and car sharing do a further favor for the environment by reducing the number of polluting vehicles on the road.
But the sharing economy is not without its problems. The sharing economy is developing faster than existing regulations and related laws are still on the way. Some companies are taking unfair advantage of this situation to expand their share of the market, often at the expense of more traditional companies. In addition, the sharing economy is subject to abuse of trust. Some people have experienced damage to their properties while renting out their homes, and others have found themselves victims of theft or attack while sharing rides. Finally, personal data is not yet safe. Sharing platforms collect personal information about almost every part of our lives.
Nonetheless, there is no doubt that the sharing economy is increasingly relevant to our daily lives as well as to the global economy. it is growing at such a rate that we can only imagine what it will be like in the future.
1. Paragraph 2 and 3 are mainly about the ________ of sharing economy.| A．definition | B．benefits | C．technology | D．development |
| A．rules | B．ideas | C．conditions | D．ways |
| A．lead to unfairness among strangers |
| B．cause distrust to traditional companies |
| C．bring about safety problems to users |
| D．limit the awareness of self-protection |
| A．Negative. | B．Doubtful. | C．Positive. | D．Unclear. |
