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发布时间：2006-06-21 20:41     点击：

Pollution

The most serlous result of air pollution is from its harmful effect, on human

health. Both gases and particuiates burn people's eyes and irritate the lungs.

Particulates can settle in 1ungs and worsen such respiratory diseases as asthma and

bronchitis. Some expers even beIieve that particulates may cause such diseases as

cancer emphysema and pneumonla. '

Air pollution also harm plans. Poisonoas gases in the air will turn into acid

rain which spread over thou'ands of square kilometers and restric the growth and

even,ually kill nearly all kinds of plants.

Polluted air can corrode such hard and strong materials as concrete and steel .

which are widely used in building houses and constructions. In some cities. statues

and other sculptares and art obiects outdoors have dislntegrated as a result of

erosion by polluted air.'

But advance in controlling exhaust from automobiles has been limited. Filters

used inare not efficient in absorbing poisonous gase. and particulates To reduce

hazardous. experts resort to new types of engines and new fuel.. The idea and

prototypes of engincs have long been proposed and tested. Fuel in the turbine engine

can be burned almostly completely . producing more power, releasing less unburned

hydrocarbons and almost no carbon monoxide

The harnessing of the new energy

With the increasing concern over hazardous environmental consequences caused by

burn-ing fos.il fuel. fuel cells now win favor in Japan and the U. S. . Experts

predict that fuel cellswill eventually replace nuclear plants in 20 to 30 years,

supplying eiectricity to households.and they will be used in cars and in space

stations, as the major engines. Researchers are working hard to reduce their volume

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