题目内容

对UV法进行准确度考查时,回收率一般为

A. C2%
B. 99.7%~100.3%
C. 98%~102%
D. 1%
E. 0.2%

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[α]tD

A. 百分吸收系数
B. 比旋度
C. 折光率
D. 熔点
E. 沸点

The Cold Places The Arctic is a polar region. It surrounds the North Pole. Like Antarctica, the Arctic is a land of ice and snow. Antarctica holds the record for a low temperature reading—125 Fahrenheit below zero. Readings of 85 degrees below zero are common in both the Arctic and Antarctica. Winter temperatures average 30 degrees below zero in the Arctic. At the South Pole the winter is about 73 degrees below zero. One thing alone makes it almost impossible for men to Jive in Antarctica and in parts of the Arctic. This one thing is the low temperature—the killing chili of the far North and the polar South. To survive, men must wear the warmest possible clothing. They must build windproof shelters. They must keep heaters going at all times. Not even for moment can they be unprotected against the below-zero temperature. Men have a way of providing for themselves. Polar explorers wrap themselves in warm coats and furs. The cold makes life difficult. But the explorers can stay alive. What about animals Can they survive Do we find plants Do we find life in the Arctic and the Antarctica Yes, we do. There is life in the oceans. There is life on land. Antarctica, as we have seen, is a cold place indeed. But this has not always been the case. Expedition scientists have discovered that Antarctica may have been much like our own. Explores have discovered coal in Antarctica. This leads them to believe that Antarctica at one time was a land of swamps and forests. Heat and moisture must have kept the trees in the forests alive. Despite the hostile environment, both animals and plants can be found in the oceans and on land in polar areas.

A. Right
B. Wrong
C. Not mentioned

Storms Sink Ships Rescuers have found the bodies of over 130 people killed in two ferry disasters in Bangladesh. The accidents happened during a storm that hit the country on April 21 Hundreds more are missing or feared dead. The two ferries sank in different rivers near the capital city of Dhaka as strong winds and rain hit the South Asian country. The government has since banned all ferries and other boats from travelling at night during the April-May stormy season. One of the ferries, MV Mitali, was carrying far more people than it was supposed to. About 400 passengers fitted into a space made for just 300, police said The second ferry carried about 100 passengers. "The number of deaths is certain to rise, " said an official in charge of the rescue work. "No one really knows how many people were on board the ferry or how many of them survived. " Ferries in Bangladesh don’t always keep passenger lists, making it difficult to determine the exact number of people on board. Besides the ferry accidents, at least 40 people were killed and 400 injured by lightning strikes, falling houses and trees and the sinking of small boats. Storms are common this time of year in Bangladesh, as are boating accidents. Ferry disasters take away hundreds of lives every year in a nation of 130 million people. Officials blame these river accidents on a lack of safety measures, too many passengers in boats and not enough checks on weather conditions. Ferries are a common means of transport in Bangladesh. It is a country covered by about 230 rivers. Some 20,000 ferries use the nation’s waterways(水路)every year. And many of them are dangerously overcrowded (过度拥挤). Since1977, more than 3,000 people have died in some 260 boating accidents. Which of the following statements is NOT true of the two ferry disasters

A. They traveled during the April-May stormy season
B. They sank on April 21
C. The exact number of deaths could be easily determined
D. They sank somewhere near Dhaka

The Cold Places The Arctic is a polar region. It surrounds the North Pole. Like Antarctica, the Arctic is a land of ice and snow. Antarctica holds the record for a low temperature reading—125 Fahrenheit below zero. Readings of 85 degrees below zero are common in both the Arctic and Antarctica. Winter temperatures average 30 degrees below zero in the Arctic. At the South Pole the winter is about 73 degrees below zero. One thing alone makes it almost impossible for men to Jive in Antarctica and in parts of the Arctic. This one thing is the low temperature—the killing chili of the far North and the polar South. To survive, men must wear the warmest possible clothing. They must build windproof shelters. They must keep heaters going at all times. Not even for moment can they be unprotected against the below-zero temperature. Men have a way of providing for themselves. Polar explorers wrap themselves in warm coats and furs. The cold makes life difficult. But the explorers can stay alive. What about animals Can they survive Do we find plants Do we find life in the Arctic and the Antarctica Yes, we do. There is life in the oceans. There is life on land. Antarctica, as we have seen, is a cold place indeed. But this has not always been the case. Expedition scientists have discovered that Antarctica may have been much like our own. Explores have discovered coal in Antarctica. This leads them to believe that Antarctica at one time was a land of swamps and forests. Heat and moisture must have kept the trees in the forests alive. Polar explorers can stay alive without heaters and windproof shelters.

A. Right
B. Wrong
C. Not mentioned

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