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 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(硅片)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(电池), 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 Docera at a conference of the American Chemical Society．
An 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 prorotype(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, inexpensive catalysts．These catalysts make the energy transformation(转换)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．Besides, 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 “giving energy to the poor”, scientists believe that the new application could be widely used in developing countries, especially in India and rural China．
(1)
Which of the following order 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．
cbad
B．
cabd
C．
bcad
D．
cadb
(2)
Which of the following statements about new artificial leaves is TRUE according to the article?
[ ]
A．
They are inexpensive but unstable．
B．
They are as efficient at carrying out photosynthesis as natural leaves．
C．
They can work only in pure water．
D．
They need several catalysts to help them work efficiently．
(3)
The aim of the scientists at MIT in developing the new artificial leaves 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
To take the apple as a forbidden fruit is the most unlikely strory the Christians(基督教徒)ever cooked up．For them, the forbidden fruit from Eden is evil(邪恶的)．So when Colu brought the tomato back from South America, a land mistakenly considered to be eden, ever jumped to be the obvious conclusion．Wrongly taken as the apple of Eden, the tomato was shut o the door of Europeans．
What made it particularly terrifying was its similarity to the mandrake, a plant that was the to have come from Hell(地狱)．What earned the plant its awful reputation was its roots w looked like a dried-up human body occupied by evil spirits．Tough the tomato and the man were quite different except that both had bright red or yellow fruit, the general population consio them one and the same, to terrible to touch．
Cautious Europeans long ignored the tomato, and until the early 1700s most of the We people continued to drag their feet．In the 1880s, the daughter of a well-known plant expert that the most interestinig part of an afternoon tea at her father's house had been the “introduction this wonderful new fruit-or is it a vegetable?”As late as the twentieth century some writers classed tomatoes with mandrakes as an”evil fruit”．
But in the end tomatoes carried the day．The hero of the tomato was an American named R Johnson, and when he was publicly going to eat the tomato in 1820, people journeyed for hun of miles to watch him drop dead．”Wha are you afraid of?”he shouted．”I'll show you fools these things are good to eat!” Then he bit into the tomato．Some people fainted．But he sur and, according to a local story, set up a tomato-canning factory．
(1)
The tomato was shut out of the door of early Europeans mainly because ________．
[ ]
A．
it made Christive evil
B．
it was the apple of Eden
C．
it came from a forbidden land
D．
it was religiously unacceptable
(2)
What can we infer the underlined part in Paragraph 3?
[ ]
A．
The process of ignoring the tomato slowed down
B．
There was little pregress in the study of the tomato
C．
The tomato was still refused in most western countries
D．
Most western people continued to get rid of the tomato
(3)
What is the main reason for Robert Johnson to eat the tomato Publicly?
[ ]
A．
To manke imself a hero
B．
To remove people's fear of the tomaoto
C．
To speed up the popularityt of the tomato
D．
To persuade people to buy products fo\rom his factory
(4)
What is the main purpose of the passage?
[ ]
A．
To challenge people's fixed concept of the tomato
B．
To give an explanation to people's dislike of the tomato
C．
To present the change of people's attitudes to the tomato
D．
To show the process of freeing the tomato from religious influence
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