某开关电源的+5伏没有输出,+24伏正常,以下故障有可能的是()。 A.输入级整流电

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问题:

某开关电源的+5伏没有输出,+24伏正常,以下故障有可能的是()。

A.输入级整流电路部分故障

B.开关管烧坏

C.输入级滤波电路部分故障

D.输出级保险烧坏

考点:数控机床装调维修工数控机床装调维修工(高级)数控机床装调维修工(高级)题库
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阅读理解。

       Why do you think people who live in some hot countries eat very spicy (辛辣的) food? Is it because the

spices make the food taste better? Is it just because their parents and grandparents and great-grandparents liked

hot food, or is there some connection between spices and healthy food?

       Researchers from Cornell University think that it is because spice plants have some important chemicals

(化学物质). These chemicals can kill bacteria (细菌) which spoil food. "Most common spices can kill 75 to 100

percent of the bacteria in food," explains one of the scientists. The bacteria grow more easily and spoil food

more quickly at higher temperatures. For this reason, it is more difficult to keep food from spoiling in hot

climates.

       Do you like your food spicy? Your answer probably tells something about the country you come from. If

you like spicy food, it is possible that hundreds of years ago, when there were no fridges, people in your

country started using spices to keep the food from spoiling. The traditional spicy dishes helped those people to

live longer, healthier lives. Today, in a time of fridges, the spices just make the food taste good.

1. The chemicals in spices keep food from spoiling by_______.[ ]

A. making food taste better

B. making food hotter

C. killing bacteria in food

D. preventing bacteria getting into food

2. Food goes bad more quickly in hot climates because _______. [ ]

A. high temperature makes more bacteria

B. high temperature helps bacteria grow faster

C. bacteria get used to hot food

D. bacteria spoil food only at high temperature

3. According to the passage, spices are useful in an the following things except _______.[ ]

A. replacing fridges

B. helping you to live longer

C. helping to keep you healthier

D. making your food taste better

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可导而下

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男,16岁,右肘部摔伤2天。右肘关节肿胀,压痛明显,活动受限,内上髁处有骨擦感。对诊断有意义的首选检查是()

A.核素骨扫描

B.X线摄片

C.B型超声

D.CT

E.MRI

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“一带一路”建设要加强双边投资保护协定、避免()磋商,保护投资者的合法权益。

A、双重征税协定

B、反复征税协定

C、重复征税协定

D、多重征税协定

题型:单项选择题

对涉及到产品性能、环保、安全的关键外购/外协件,即公司零部件分类中的A、B类产品,可对供方作哪些控制?()

A、定期(不超过1年)向本公司提供国家认定部门出具的试验报告;

B、按本公司规定检验,随产品提交规定的检验、试验数据或过程记录;

C、实施本公司规定的ISO9001/TS16949质量管理体系开发计划;

D、接受本公司或由本公司委托的第三方对质量保证能力进行现场评价。

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