风冷干式变风机自动启、停及超温报警、跳闸的温度设定()℃风机停;()℃风机启;130

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风冷干式变风机自动启、停及超温报警、跳闸的温度设定()℃风机停;()℃风机启;130℃报警;150℃跳闸。

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“金蝉脱壳”的壳在生物学上是指      

A.皮肤

B.甲壳

C.外骨骼

D.鳞片

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美国发明了月球制氧机,它利用聚焦太阳光产生的高温使月球土壤发生化学反应放出氧气.由此可推测月球土壤中一定含有

[ ]

A.氧元素

B.氧分子

C.水分子

D.氯酸钾

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武松杀嫂故事中出现的小厮名叫()。

A、牛二

B、郓哥

C、唐牛儿

D、李狗儿

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不属于动力燃烧特点的是()。

A、边混合边燃烧

B、燃烧反应快

C、温度高

D、火焰传播速度快

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(四)

With only about 1 000 pandas left in the world, China is desperately trying to clone the animal and save the endangered species. That’s a move similar to what a Texas A & M University researchers have been undertaking for the past five years in a project called "Noah’s Ark’.

Noah’s Ark is aimed at collecting eggs, embryos, semen and DNA of endangered animals and storing them in liquid nitrogen. If certain species, should become extinct, Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.

It is estimated that as many as 2000 species of mammals, birds reptiles will become extinct in over 100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.

This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.

The entire procedure could take from three to five years to complete.

"The nuclear transfer of one species to another is not easy, and the lack of available(capable of being used) panda eggs could he a major problem," Kraemer believes. "They will probably have to do several hundred transfers to result in one pregnancy(having a baby). It takes a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort," adds Kraemer, who is one of the leaders of the Project at Texas A & M, the first-ever attempt at cloning a dog.

"They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed. \

The best title for the passage may be ().

A.China’s Success in Pandas Cloning

B.The First Cloned Panda in the World

C.Exploring the Possibility to Clone Pandas

D.China—the Native Place of Pandas Forever

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