2020英语教学资源：时文阅读|新型材料有望解决水中塑料污染问题

时文阅读|新型材料有望解决水中塑料污染问题

在世界范围内，海洋与河道中的塑料污染问题已困扰人们多年，它们给生态环境和水中的生物带来的危害是难以估量的。如今，化学家们研发出一种新型聚合物，有望解决这一难题。

阅读短文并回答问题

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 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-dependent, but under their laboratory conditions, the polymer chain lengths degraded to a quarter of their original length after 30 days of exposure.”

 Lipinski and other scientists want no trace 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 special about the new polymer?

A. It can reduce plastic consumption.

B. It is expected to lower fishing costs.

C. It can degrade plastic waste in the sea water.

D. It has been developed to solve plastic pollution.

2. What can we infer from paragraph 3?

A. Fishing should be forbidden in the sea.

B. It requires great effort to invent the new plastic.

C. Nets and ropes are not the major pollution source.

D. Degradable plastics were not studied until recently.

3. What did the recent study find about iPPO?

A. Its original use.                  

B. Its special intensity.     

C. Its mechanical strength.

D. Its complex composition.

4. What is Lipinski’s attitude towards the future of iPPO?

A. Hopeful.        B. Indifferent.        C. Skeptical.          D. Negative.

【参考答案】DBCA

 

单词学习

1. persistent  adj. 持续存在的

  Her cough grew more persistent until it never stopped.  她的咳嗽越来越频繁，直到咳个不停。

2. comparable  adj. 可比较的

  The situation in the US is not directly comparable to that in the UK.

  美国的情况与英国的不能直接相比。

3. isotactic  adj. （立体有择聚合物）全同立构的

4. polypropylene  n. 聚丙烯

5. oxide  n. 氧化物  iron oxide 氧化铁

6. mechanical strength  机械强度

7. ongoing  adj. 进行中的

  There is an ongoing debate on the issue.  关于这个问题的争论还在继续。

 

     长难句分析

To address plastic pollution troubling the world’s seas and waterways, Cornell University chemists have developed a new polymer that can degrade when exposed to ultraviolet radiation, according to the research published in the Journal of the American Chemical Society.

【分析】句子主干为“chemists have developed a polymer”；“To address plastic pollution troubling the world’s seas and waterways”为目的状语，其中“troubling the world’s seas and waterways”为现在分词作后置定语，修饰“plastic pollution”；主句中的“that can degrade when exposed to ultraviolet radiation”为定语从句，修饰先行词“polymer”，其中 “when exposed to ultraviolet radiation”为定语从句中的时间状语从句，“when”后省略了it is；“published in the Journal of the American Chemical Society”为过去分词作后置定语，修饰“the research”。

【翻译】《美国化学会志》上发表的一项研究中提到，为了解决困扰世界海洋和水道的塑料污染问题，康奈尔大学的化学家们研发了一种新的聚合物，该聚合物暴露在紫外线辐射下可降解。

 

   知识拓展

1. Cornell University  康奈尔大学，创立于1865年，位于美国纽约州伊萨卡，是一所享誉世界的顶级私立研究型大学。它是美国大学协会的十四个创始院校之一，也是著名的常春藤盟校的八个成员之一。

2. Journal of the American Chemical Society  《美国化学会志》，是美国化学学会下的期刊之一。美国化学学会是一个化学领域的专业组织，成立于1876年。

 

声明

原文选自ScienceDaily，试题与内容讲解由天学网教学研究中心编写。