直流电动机拖动同轴提升机时的效率为()。 A.0.85~0.9 B.0.95~1 C

题型:单项选择题

问题:

直流电动机拖动同轴提升机时的效率为()。

A.0.85~0.9

B.0.95~1

C.1

D.1~1.5

考点:矿井维修电工矿井维修电工(高级技师)矿井维修电工(高级技师)题库
题型:单项选择题
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题型:单项选择题
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题型:单项选择题

The Internet, mobile phones and iPads are part of our lives now. Technology is greatly affecting all ways of our lives, from the ways we work to the ways we play. And it even causes a number of social problems such as cloning humans.

We have had lots of technology and it has changed our lives a lot. There is no doubt that humans will continue to use more and more technology. Here are some examples of modern technology that will change our ideas and will affect our lives greatly.

Global Positioning System (GPS) (全球定位系统)

It’s a system that uses radio signals from satellites to show exact (精确的) information. It tells you where the user is on the earth in all weather conditions. It’s made up of three parts: satellites, control equipments (设备) on land and receivers.

Space Technology

Russian and American scientists have worked together for the International Space Station (ISS) for a long time. They hope the ISS will provide a long-lasting lab. Such a lab will bring humans limitless (无限的) advantages. It’s even hoped that one day space technology will take humans to their new houses in space.

Underwater Robot

Hercules is a kind of underwater robot with some high technology equipments. It will be used to search for ancient ships which were destroyed into the deep sea during their journey long ago.

The world is changing so quickly that it’s hard for us to catch up with all the new inventions because they seem to come out every month. It’s important for us to learn about new technology and the role that it plays in our lives. So we should be willing to accept modern technology, or we will fall behind the times.

小题1:                  can tell you where the user is on the earth exactly.

A.Satellites

B.Receivers

C.Global Positioning System

D.Underwater Robot小题2:According to the passage, which is NOT true about the ISS?

A.It has carried people to other planets.

B.It will provide a long-lasting lab for us.

C.Russia and America are working for it.

D.Humans will get a lot of advantages from it.小题3:Hercules is used to                   .

A.save lives in the sea

B.take pictures in the sea

C.repair the broken ships

D.look for the ancient ships in the sea小题4:From the passage, we know that                   .

A.the use of GPS is affected by the weather conditions

B.it’s very important for us to learn about new technology

C.it’s easy for us to catch up with all the new inventions

D.technology brings us many advantages such as cloning humans小题5:What is the purpose of the passage?

A.To help us study some new technology.

B.To tell us technology is changing the world.

C.To help solve the problems that technology causes.

D.To remind us the advantages of technology are limitless.

题型:单项选择题

患者女,42岁,因“乏力,伴轻微恶心、食欲减退6个月余”来诊。查体:P80次/min,BP140/70mmHg;轻度贫血貌;心、肺未见明显异常;双下肢不肿。实验室检查:Hb101g/L,SCr260μmol/L;尿蛋白(+++),尿隐血(+)。

为进一步明确诊断,相关检查不包括()

A.24h尿蛋白定量

B.泌尿系统超声

C.肾穿刺活检

D.血液免疫学检查

E.静脉肾盂造影

题型:单项选择题

戒烟项目中完全不吸烟属于()

A.无转变打算阶段

B.打算转变阶段

C.转变准备阶段

D.转变行为阶段

E.行为维持阶段

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