Question

【题目】

What will power your house in the future? Nuclear, wind, or solar power? According to scientists at the Massachusetts Institute of Technology（MIT） in the US, it might be leaves-but artificial（人造的）ones.

Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis（光合作用）. Now researchers have found a way to imitate this seemingly simple process.

The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts（催化剂）. Similar to natural leaves, it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell, which uses those two materials to produce electricity, located either on top of a house or beside the house.

Though the leaf is only about the shape of a poker card, scientists claimed that it is promising to be an inexpensive source of electricity in developing countries. "One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology，" said Nocera at a conference of the American Chemical Society.

The artificial leaf is not a new idea. The first artificial leaf was invented in 1997 but was too expensive and unstable for practical use. The new leaf, by contrast, is made of cheap materials, easy to use and highly stable. In laboratory studies, Nocera showed that an artificial leaf prototype （原型）could operate continuously for at least 45 hours without a drop in activity.

The wonderful improvements come from Nocera's recent discovery of several powerful, new and inexpensive catalysts. These catalysts make the energy transformation inside the leaf more efficient with water and sunlight. Right now, the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Be-sides, the device can run in whatever water is available; that is, it doesn't need pure water. This is important for some countries that don't have access to pure water.

With the goal to " make each home its own power station" and" give energy to the poor"，scientists believe that the new technology could be widely used in developing countries, especially in India and rural China.

【1】 Which of the following orders correctly shows how the artificial leaf is used to produce electricity?

a. artificial leaves split water into hydrogen and oxygen

b. the hydrogen and oxygen gases are stored in a fuel cell

c. the artificial leaves are put in water

d. the fuel cell uses hydrogen and oxygen to produce electricity

A. c, b，a, d

B. c, a，b, d

C. b, c，a, d

D. c, a，d, b

【2】 The purpose of the scientists at MIT in developing the new artificial leaf is to __________.

A. build up more power stations in the world

B. provide cheaper energy for developing countries

C. offer people in developing countries access to pure water

D. gain a deeper understanding of the photosynthesis process

【3】 The main idea of this passage is __________.

A. an introduction to the history of artificial leaves

B. an invention copying photosynthesis

C. giving energy to the poor

D. mixture of water power and solar energy

【4】 The underlined word " imitate" in Paragraph 2 can be replaced by "__________".

A. produce

B. hold

C. prevent

D. copy

Answer 1

【答案】【1】 B

【2】 B

【3】 B

【4】 D

【解析】文章介绍了科学家利用人造树叶仿效光合作用进行发电这一新发明。

【1】 细节理解题。文章的第三段提到人造树叶发电的过程：先把它放在一桶水里，然后树叶将水分解为氢气和氧气，而氢气和氧气被存储于燃料电池里，随后电池利用氢气和氧气的反应发电。

【2】 推理判断题。根据最后两段内容可知，人造树叶发电这一技术可以帮助发展中国家获得便宜的能源。

【3】 主旨大意题。综观全文可知，本文主要讲述了人造树叶模拟光合作用发电这一新发明。

【4】 词义猜测题。画线部分的前文介绍了什么是光合作用，后文介绍了利用人造树叶效仿这种光合作用进行发电，所以该词的含义应该是“仿效”，故D项是最佳答案。