To address the plastic pollution troubling the world’s seas and waterways, Cornell University chemists have developed a new polymer (聚合物) that can degrade (降解) plastic when exposed to ultraviolet radiation, according to the research published in the Journal of the American Chemical Society.
“We have created a new plastic that has the mechanical properties required by commercial fishing gear. If it eventually gets lost in the water environment, this material can degrade on a realistic time scale,” said lead researcher Bryce Lipinski, professor of chemistry and chemical biology at Cornell University. “This material could effectively reduce persistent plastic accumulation in the environment.”
Commercial fishing contributes to about half of all floating plastic waste that ends up in the oceans. Fishing nets and ropes are primarily made from three kinds of polymers, none of which easily degrade. “While research of degradable plastics has received much attention in recent years,” Lipinski said, “obtaining a material with a mechanical strength comparable to commercial plastic remains a difficult challenge.”
Coates and his research team have spent the past 15 years developing the new plastic called isotactic polypropylene oxide, or iPPO. While its original discovery was in 1949, the mechanical strength of this material was unknown before this recent work. The high isotacticity and polymer chain length of their material makes it different from previous plastics and provides its mechanical strength.
Lipinski and other scientists want no race of the polymer to be left in the environment. He notes there is precedent (先例) for the biodegradation of small chains of iPPO which could effectively make it disappear and ongoing efforts aim to prove this.
【小题1】What is the feature about the new polymer?| A．It can solve the problem of plastic consumption. |
| B．It can degrade plastic waste in the sea water. |
| C．It has been developed to solve plastic pollution. |
| D．It has been developed to lower fishing costs. |
| A．It requires great effort to invent the new plastic. |
| B．Fishing should be forbidden in the sea. |
| C．Fishing nets and ropes are not the major pollution source. |
| D．Degradable plastics were not paid attention to until recent years. |
| A．Its original discovery. | B．Its mechanical properties. |
| C．Its complex structure. | D．Its mechanical strength. |
| A．Doubtful. | B．Promising. |
| C．Unconcerned. | D．Disapproval. |
The project, called Hywind, is the world’s first large-scale deepwater wind turbine(涡轮发电机).Although it uses a fairly standard 152-ton,2.3-megawatt turbine, Hywind represents totally new technology. The turbine will be fixed 213 feet above the water on a floating spar(see picture),a technology Hywind’s creator, the Norwegian company StatoilHydro, has developed recently. The steel spar, which is filled with stones and goes 328 feet below the sea surface, will be tied to the ocean floor by three cable(缆索)；these will keep the spar stable and prevent the turbine from moving up and down in the waves. Hywind’s stability(稳定性)in the cold and rough sea would prove that even the deepest corners of the ocean are suitable for wind power. If all goes according to plan, the turbine will start producing electricity six miles off the coast of southwestern Norway as early as September.
To produce electricity on a large scale, a commercial wind farm will have to use bigger turbines than Hywind does, but it’s difficult enough to balance such a large turbine so high on a floating spar in the middle of the ocean. To make that turbine heavier, the whole spar’s to design a new kind of wind turbine, one whose gearbox(变速箱) sits at sea level rather than behind the blades (see picture )
Hywind is a test run, but the benefits for perfecting floating wind-farm technology could be extremely large. Out at sea, the wind is often stronger and steadier than close to shore, where all existing offshore windmills are planted. Deep-sea farms are invisible from land, which helps overcome the windmill-as-eyesore objection. If the technology catches on, it will open up vast areas of the planet’s surface to one of the best low-carbon power sources available.
【小题1】The Hywind project uses totally new technology to ensure the stability of _______.
| A．the cables which tie the spar to the ocean floor |
| B．the spar which is floating in deep-sea water |
| C．the blades driven by strong and steady sea wind |
| D．the stones filled in the spar below the sea surface |
| A．on the sea floor | B．on the spar top |
| C．at sea level | D．behind the blades |
| A．solve the technical problems of deepwater windmills |
| B．make financial profits by producing more turbines |
| C．settle the arguments about environmental problems |
| D．explore low-carbon power resources available at sea |
When scientists go to a forest to study monkeys and their habits and behaviors, how do they know who’s who?
In the past, scientists had to make marks on each of the animals to distinguish them. But in the future, they may have a much easier way to tell them apart thanks to facial recognition technology.
A research team from China’s Northwest University is using facial recognition technology to identify thousands of snub-nosed monkeys that live on Qinling Mountain in Shaanxi province.
Similar to human facial recognition, the technology that is used to identify monkeys uses their facial features to create a database that includes every monkey, Xinhua reported. “When the system is fully developed, we can connect it with cameras set up in the mountains. The system will automatically recognize the monkeys, name them and analyze their behavior,” said Zhang He, a member of the research team. “For each snub-nosed monkey, we have 700 to 800 image samples, and the recognition success rate is 94 percent,” Zhang added.
“We used mobile phones and portable cameras with the monkeys in tests at distances ranging from about 3 to 10 meters,” said He Gang, a member of the research team and an associate professor in the College of Life Sciences at Northwest University. “There is no need to interfere with the monkeys. Such a method of sampling is clearly non-invasive.”
Compared to humans, facial recognition technology for monkeys is more complicated because of their hairier faces. The color of their hair causes them to blend into their environment. These factors make it harder for computers to identify them.
“Monkeys do not cooperate with researchers in the same way humans do. It is difficult to take high-quality pictures and videos of them, which are needed to improve the system,” said Li Baoguo, leader of the research team.
Currently, there are about 4,000 snub-nosed monkeys living on Qinling Mountain. The team’s goal is to successfully identify every monkey that lives there.
【小题1】What problem do scientists face while studying monkeys according to the text?| A．How to mark them. | B．How to tell them apart. |
| C．How to understand their behavior. | D．How to observe them clearly |
| A．It is now widely adopted in China. |
| B．It works better than human facial recognition. |
| C．It will use monkeys’ behavior to create a database. |
| D．It can help scientists study monkeys without disturbing them. |
a. Image samples. b. Hairy faces. c. Hair color. d. The environment.
| A．ab | B．ac | C．bc | D．bd |
| A．To introduce a new way to identify monkeys. |
| B．To show the importance of studying monkeys. |
| C．To compare different ways to identify monkeys. |
| D．To explain difficulties in developing a new system. |
Technology has changed our lives and reshapes the way we live. Some of us love it and some of us are frustrated (懊恼的) with it. This is clear as most of us are guilty of being addicted to the Internet and social media.
The invention of airplanes, ships and spacecraft always allows people to visit other countries and even other planets. As long as we follow the laws of immigration, we can go to any country we like.
In addition, technology is also used by a large number of teachers to improve their teaching. It can make the lessons more interactive and interesting for students. E-learning is possible with the use of the Internet connection and computers. People wishing to study for a degree can do so at their comfortable homes.
However, we have to say that technology can be a double-edged sword. Nowadays, instead of paying attention to the conversation we are having face to face, we just take the phone. We are distracted by smartphones and technology in general. But we can’t blame technology. We should not blame ourselves, either.
| A．This gives students flexibility. |
| B．What we need to do is to find some balance. |
| C．This makes it easy for students to make progress. |
| D．Nevertheless, we have seen some benefits of technology. |
| E．When it comes to shopping, technology is also of great help. |
| F．Besides, we have suffered a lot from modern communication. |
| G．And of course, travelling can make people’s lives more colorful. |
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