题目

阅读理解 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. （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. （2） What can we infer from paragraph 3? 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. （3） What did the recent study find about iPPO? A . Its original discovery. B . Its mechanical properties. C . Its complex structure. D . Its mechanical strength. （4） What is Lipinski's attitude towards the future of iPPO? A . Doubtful. B . Promising. C . Unconcerned. D . Disapproval. 答案： C A D B

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