郑西（郑州-西安）高速铁路客运专线已于2010年2月6日建成通车．_爱下问搜题

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问题问答题

郑西（郑州-西安）高速铁路客运专线已于2010年2月6日建成通车．专线全长505km，承担运行任务的“和谐号”动车组，最高车速可达350km/h．为了确保行车安全，列车上的监控系统，通过对高速运转车轮的热辐射产生的一种不可见光进行检测，实现对车轮温度的实时监控．这种不可见光是______．

答案

车轮高速转动时，温度较高，辐射红外线的本领增强，可以实现对车轮温度的实时监控．

故答案为：红外线．

完形填空

Computers can injure (伤害) you. Most other injuries happen suddenly. For example, if you fall over a bike and break your arms, it happens very     . But computer injuries happen slowly. You probably know how to ride a bike safely. Now learn to use a computer safely.
Your eyes     light can injure your eyes,      never sit too close to a computer screen. Your eyes should be       50centimeters（厘米）on the screen.      remember to look away from it. This gives your eyes a rest. When you use a computer, the window         be on your left or your right. If it is behind you, the light will reflect on（反射）the screen. If the window is in front of you, the sun and the screen will        shine into your eyes.
Your hands and wrists(手腕)
Hand and wrist injuries can happen because the hands and wrists are moved in the same way. Hundreds of times. If you use a keyboard for a long time,         these three rules: 1）Rest your wrists on something. 2）Keep your elbows（肘）at the same height as the keyboard. 3）Stop sometimes and exercise your hands, wrists and fingers in a different way.
Your back
Some people sit for many hours in front of a computer. If you sit in the wrong way, you can injure your back or your neck. So you should sit with your back straight. The top part of the screen should be in front of your eyes. Your forearms, wrists, hands and the upper part of your legs should all be parallel（平行）to the floor. If you are sitting for a long time, get up every 30 minutes and        your arms, legs and neck.      your computer, but use it safely.

A．much quickly

单项选择题

送电线路的杆塔总体来说分为（）

A.直线型耐张型

B.直线型耐张型转角型

C.直线型和转角型