2020届山东年上学期湖北部分重点中学高三英语新(9)

【31题详解】

推理判断题。阅读文章，并根据最后一段Despite these many examples of numerical competence in animals, this subject has not gotten many first-hand studies. 可知，本文讲述最近一项研究，动物不仅具有理解数字的能力，而且这一能力还对它们的日常生活有着巨大的影响，所以本文应该选自一篇研究论文。故选D。

D

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) when exposed to ultraviolet (紫外线的) 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 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 the 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 noted that while iPPO is stable in ordinary use, it eventually breaks down when exposed to UV light. The change in the plastic’s composition is evident in the laboratory, but “visually, it may not appear to have changed much during the process,” he said, “The rate of degradation is light intensity-

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