[判断题]变压器运行巡视应检查变压器上层油温,正常时一般应在95℃以下-我要搜题网

[不定项选择题]共用题干 Food Fright
Experiments under way in several labs aim to create beneficial types of genetically modified(GM)foods,including starchier potatoes and caffeine-free coffee beans.Genetic engineers are even trying to transfer genes from a cold-water fish to make a frost-resistant tomato.A low-sugar GM strawberry now in the works might one day allow people with health problems such as diabetes to enjoy the little delicious red fruits again.GM beans and grains supercharged with protein might help people at risk of developing kwashiorkor. Kwashiorkor,a disease caused by severe lack of protein,is common in parts of the world where there are severe food shortages.
Commenting on GM foods,Jonathon Jones,a British researcher,said,"The future benefits will be enormous,and the best is yet to come."
To some people,GM foods are no different from unmodified foods."A tomato is a tomato," said Brian Sansoni,an American food manufacturer.
Critics of GM foods challenge Sansoni's opinion.They worry about the harm that GM crops might do to people,other animals,and plants.
In a recent lab study conducted at Cornell University,scientists tested pollen made by Bt corn,which makes up one-fourth of the U .S.corn crop.The scientist sprinkled the pollen onto milkweed,a plant that makes a milky juice and is the only known food source of the monarch but-terfly caterpillar. Within four days of munching on the milkweed leaves,almost half of a test group of caterpillars had died."Monarchs are considered to be a flagship species for conservation,"said Cornell researcher Linda Raynor."This is a warning bell."
Some insects that are not killed by GM foods might find themselves made stronger. How so? The insecticides used to protect most of today's crops are sprayed on the crops when needed and decay quickly in the environment.But GM plants produce a continuous level of insecticide.Insect species feeding on those crops may develop resistance to the plants and could do so in a hurry, say the critics.Insects may also develop a resistance to the insecticide Bt.
At the forum on GM food held last year in Canada,GM crops that have been made resistant to the herbicide might crossbreed with wild plants,creating"superweeds"that could take over whole fields.
So where do you stand?Should GM foods be banned in the United States,as they are in parts of Europe?Or do their benefits outweigh any of the risks they might carry? Paragraphs 1,2&3 try to give the idea that______.
A.GM foods are particularly good to the kwashiorkor patients
B.GM foods may have both benefits and harm
C.we cannot recognize the benefits of GM foods too early
D.GM foods may bring about great benefits to humans

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[多选题]依据《中国南方电网有限责任公司电力安全工作规程》（Q/CSG 510001—2015）第27.2.8条规定：作业现场使用的带电作业工具应放置在( )上。
A.地面
B.防潮的帆布
C.设备
D.绝缘物

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[单选题]对室内用电设备的供电，采用电缆引入方式的，以（）分界。
A.开关
B.开关箱送电端子
C.电缆终端头
D.开关箱中的电源端子

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[单选题] 依据《中国南方电网有限责任公司安全生产禁令》第三条的规定，严禁安排（）的电网运行方式。
A. 超限额
B. 安全裕度不足
C. 长时超负荷运行
D. 超能力

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[单选题]装有104型电空制动机的车辆在进行空气制动试验时，常用制动保压后自然缓解，其可能的故障部位有（）。
A.主阀故障
B.工作风缸管路或容积室有漏泄
C.单向阀有逆流
D.以上都有可能

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[填空题]键连接主要是用来实现轴与轴上零件之间的() ，并传递() 和扭矩。

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[单项选择]因电力中断影响正常运输2小时以上，或影响客车1小时以上构成行车事故，事故类型为（）
A. D9
B. D14
C. D16
D. D21