Plastic is nearly everywhere — in shoes, clothes, refrigerators and construction materials. But this highly useful material can have a major defect. Made from oil and slow to break down, conventional plastic is not environmentally friendly. Today, researchers discuss inventing what they say should be a safer, biodegradable (可生物降解的) alternative made from fish waste— heads, bones and skin— that would otherwise likely be thrown out.
If developed successfully, fish-oil-based plastic could help meet the considerable need for more sustainable plastic, says Francesca Kerton, the project’s investigator. Previously, others have developed new plastic using plant-based oils. However, this too comes with a disadvantage: the crops that produce these oils require land that could otherwise be used to grow food.
Leftover fish struck Kerton as a promising alternative. Salmon (鲑鱼) farming is a major industry for coastal Newfoundland, where her university is located. After the fish are processed, leftover parts are often thrown away. Kerton and her colleagues developed a process for turning this fish oil into a plastic-like material. But does the plastic smell fishy? “When we start the process with the fish oil a slight kind of fish smell, but as we go through the steps, that smell disappears,” Kerton says.
In other experiments, they have begun examining how quickly the new material would likely break down once its useful life is over. Kerton put pieces of it in water, and to speed up the degradation for some pieces, she added a chemical capable of breaking down fats like those in the fish oil. Under a microscope, she later saw microbial (微生物的)growth on all of the samples, even those that had been in plain water, an encouraging sign that the new material might biodegrade quickly, Kerton says.
Kerton now intends to study the material’s physical properties to see how it might in real-world applications, such as in packaging or fibers for clothing.
12. What does the underlined word “defect” in paragraph 1 mean?
A.Mistake. | B.Burden. | C.Difficulty. | D.Disadvantage. |
13. What is wrong with using plant-based oils to make plastic?
A.It causes damage to the soil. | B.It needs a large amount of land. |
C.It produces an unpleasant smell. | D.It increases the price of cooking oils. |
14. What do we know about this new plastic?
A.It can break down easily. | B.It has a very short useful life. |
C.It is hard to mix with plain water. | D.It proved a good packaging material. |
15. What is the text mainly about?
A.A living trend. | B.A fishing method. |
C.A scientific project. | D.A biological phenomenon. |