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【单选题】
If good intentions and good ideas were all it took to save the deteriorating atmosphere, the planet's fragile layer of air would be as good as fixed. The two great dangers threatening the blanket of gases that nurtures and protects life on earth—global warming and the thinning ozone layer—have been identified. Better yet, scientists and policymakers have come up with effective though expensive countermeasures. But that doesn't mean these problems are anywhere close to being solved. The stratospheric ozone layer, for example, is still getting thinner, despite the 1987 international agreement known as the Montreal Protocol, which calls for a phase-out of chlorofluorocarbons (CFCs) and other ozone-depleting chemicals by the year 2006. CFCs—first fingered as dangerous in the 1970s by Sherwood Rowland and Mario Molina, two of this year's Nobel—prizewinning chemists—have been widely used for refrigeration and other purposes. If uncontrolled, the CFC assault on the ozone layer could increase the amount of hazardous solar ultraviolet light that reaches the earth's surface, which would, among other things, damage crops and cause cancer in humans. Thanks to a sense of urgency triggered by the 1085 detection of what has turned out to be an annual 'hole' in the especially vulnerable ozone over Antarctica, the Montreal accords have spurred industry to replace CFCs with safer substances. Yet the CFCs already in the air are still doing their dirty work. The Antarctic ozone hole is more severe this year than ever before, and ozone levels over temperate regions are dipping as well. If the CFC phase-out proceeds on schedule, the atmosphere should start repairing itself by the year 2000, say scientists. Nonetheless, observes British Antarctic Survey meteorologist Jonathan Shanklin: 'It will be the middle of the next century before things are back to where they were in the 1970s'. Developing countries were given more time to comply with the Montreal Protocol and were promised that they would receive $250 million from richer nations to pay for the CFC phase-out. At the moment, though, only 60% of those funds has been forthcoming. Says Nelson Sabogal of the U.N. Environment Program: 'If developed countries don't come up with the money, the ozone layer will not recuperate. This is a crucial time'. It is also a critical time for warding off potentially catastrophic climate change. Waste gases such as carbon dioxide, methane and the same CFCs that wreck the ozone layer all tend to trap sunlight and warm the earth. The predicted results: an eventual melting of polar ice caps, rises in sea levels and shifts in climate patterns. The author asserts that remedying the earth atmosphere will depend upon other measures than ______.
A.
quick responses.
B.
energy efficiency.
C.
great initiatives.
D.
scientific analysis.
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【单选题】两相继电器接线的过电流保护装置( )。
A.
既可以作相间短路保护,又可以作单相短路保护
B.
只能作相间短路保护,不能作单相短路保护
C.
只能作单相短路保护,不能作相间短路保护
D.
既不可作相间短路保护,又不可作单相短路保护
【单选题】()接线的主变压器的电流速断及过电流保护应采用“和电流”接线的过电流保护(即将两个开关的电流互感器中的二次电流相加后接入继电器或数字式保护装置)。桥开关可以不再装设保护。
A.
双母线
B.
单母线
C.
内桥
D.
分段单母线
【判断题】过电流的继电保护装置接线方式只有两相两继电器式和两相一继电器式两种接线方式。
A.
正确
B.
错误
【单选题】两相两继电器接线的过电流保护装置()
A.
既可以作相间短路保护,又可以作单相短路保护;
B.
只能作相间短路保护,不能作单相短路保护;
C.
只能作单相短路保护,不能作相间短路保护。
【多选题】以下属于分部工程的是
A.
某住宅楼的砌筑工程
B.
某车间的土石方工程
C.
某工厂的礼堂
D.
某体育馆的金属结构工程
E.
某医院的住院大楼
【单选题】两相两继电器接线的过电流保护装置( )。
A.
既可以作相间短路保护,又可以作单相短路保护
B.
只能作相间短路保护,不能作单相短路保护
C.
只能作单相短路保护,不能作相间短路保护
D.
以上都不是
【多选题】斯腾伯格的爱情三元论认为爱情包含( )
A.
依恋
B.
激情
C.
承诺
D.
亲密
【简答题】某10kV线路,采用两相两继电器式接线的去分流跳闸的反时限过电流保护装置,电流互感器的变流比为200/5A,线路的最大负荷电流(含尖峰电流)为180A,线路首端的三相短路电流有效值为2.8kA,末端的三相短路电流有效值为1kA。试整定该线路采用的GL-15/10型电流继电器的动作电流和速断电流倍数,并检验其保护灵敏度。
【多选题】以下属于分部工程的是
A.
建筑工程
B.
基础工程
C.
屋面工程
D.
挖基槽
【多选题】以下属于分部工程的是( )
A.
某商住楼的砌筑工程
B.
某车间的土石方工程
C.
某工厂的礼堂
D.
某医院的住院大楼
E.
某体育馆的金属结构工程
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