一种精密零件按5:1画在图上长是1厘米,实际长度是()cm,如果实际宽是0.1c

题型:填空题

问题:

一种精密零件按5:1画在图上长是1厘米,实际长度是(    )cm,如果实际宽是0.1cm,那么图上宽是(    )cm。

考点:比例尺
题型:填空题

正方形的边长是质数,则它的周长和面积一定是[ ]

A.质数 

B.合数

C.既不是质数也不是合数

题型:填空题

下列变化属于化学变化的是[ ]

A.酒精挥发

B.铁铸成锅

C.大米酿酒

D.胆矾研碎

题型:填空题

既往有哮喘病史的甲亢患者,不宜使用下列哪种药物

A.甲巯咪唑(他巴唑)
B.卡比马唑(甲亢平)
C.丙基硫氧嘧啶
D.普奈洛尔
E.复方碘溶液

题型:填空题

Small, pink and very ugly. Hardly the qualities of a star, but they describe the deformed mouse that was the media darling at a recent science exhibition in Beijing. With a complex tissue structure in the shape of a human ear grafted on to its back, the rosy rodent was a stunning symbol of the serious strides China is making in the field of biotechnology.

China is fast applying the latest life-science techniques learned from the West to aggressively pursue genome research. It’s establishing its own centers of technical excellence to build a scientific base to compete directly with the United States and Europe. With a plentiful supply of smart young scientists at home and lots of interest abroad biotechnology is on the brink of a boom in China. And in the view of foreign scientists, Beijing is playing a clever hand, maximizing the opportunities open to them.

For the moment, the cooperation exists mostly with Europe and the U. S. But Asia’s other biotech leaders, Japan, Singapore and Korea, also are recognizing China’s potential as an attractive low-cost base to conduct research. These partnerships—and China’s advancement in the field of biotechnology—could help benefit the rest of Asia: China’s rapid progress in improving crop yields will address food-security concerns in the region. In addition, China is more likely to focus on developing cheap technology that its predominantly poor population and those of other Asian countries—can afford.

There remain, however, serious barriers to the development of a p biotech industry. Among them are a poor domestic legal framework, weak enforcement of intellectual-property rights and loose adherence to international standards. China is a signatory of the International Bio Safely Protocol, which should mean adherence to global standards governing the conduct of field trials. But some observers are skeptical. "The regulations look good, but I haven’t met one scientist who believes they are being fully adhered to," says a European science analyst.

If shortcuts are taken, then some of the recent scientific achievements trumpeted in the official press may never make it to market. But no matter how strict lab test are, other problems lie in wait. For example, there is a number of tasks it would take years to fulfill in the patents office, says one lawyer, leaving innovators with little protection if they take a product to market in China.

The mouse on display is most significant in that ().

A. it has an ear in the shape of a human ear

B. it is unusually small and ugly as a star

C. it is the focus of the media at the exhibition

D. it indicates China’s progress in biotechnology

题型:填空题

在冰雪道路上行车时,车辆的稳定性降低,加速过急时车轮极易空转或溜滑。

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