Harvard researchers have created a tough, low-cost, biodegradable (可生物降解的) m

Harvard researchers have created a tough, low-cost, biodegradable (可生物降解的) material inspired by insects" hard outer shells. The material"s inventors say it has a number of possible uses and someday could provide a more environmentally friendly alternative to plastic. The material, made from shrimp (") shells and proteins produced from silk, is called "shrilk." It is thin, clear, flexible and strong.
   A major benefit of the material is its biodegradability. Plastic"s toughness and flexibility represented a revolution in materials science during the 1950s and "60s. Decades later, however, plastic"s very durability (
耐用性) is raising questions about how appropriate it is for one-time products such as plastic bags, or short-lived consumer goods, used in the home for a few years and then cast into a landfill where they will degrade for centuries. What is the point of making something that lasts 1,000 years?
   Shrilk not only will degrade in a landfill, but its basic components are used as fertilizer (
肥料), and so will enrich the soil.
   Shrilk has great potential, the inventors said. Materials from which it is made are plentiful in nature, found in everything ranging from shrimp shells, insect bodies to living plants. That makes shrilk low cost, and its mass production possible should it be used for products demanding a lot of material.
    Work on shrilk is continuing in the lab. The inventors said the material becomes flexible when wet, so they"re exploring ways to use it in wet environments. They"re also developing simpler production processes, which could be used for non-medical products, like for computer cases and other products inside the home. They"re even exploring combining it with other materials, like carbon fibers, to give it new properties.
11: Paragraph I of the passage is mainly about shritk"s_____.

Aremarkable design

Binteresting name

Cmajor characteristics

Dbasic elements

12: What has become a concern about plastic?

AUsing it properly.                    BProducing it cheaply.

CDeveloping its properties quickly.       DEvaluating its contributions fairly.

13: According to the inventors, shrilk has great potential partly because_____.

Ait can help plastic degrade           Bit can be found in living things

Cits mass production has been realized  Dits raw materials are abundant in nature

14:What are the inventors doing in the lab?

AReplacing carbon fibers with shrilk.

BTesting ahrilk"s use in wet conditions.

CMaking shrilk out of used household goods.

DImproving shrilk"s flexibility for medical purposes.

15:Which of the following can be the best title for the passage?

ARecent Progress in Environmental Protection

BBenefits of Insects in Scientific Research

CThe Harm of One-time Products

DA Possible Alternative to Plastic

答案

CADBD

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