天然紫外线的重要来源是______，地球周围大气层上部的______可吸_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

天然紫外线的重要来源是______，地球周围大气层上部的______可吸收紫外线，使得阳光中的紫外线大部分不能到达地面，这样就防止人类受过量的紫外线照射．一块玻璃能透过所有色光，则玻璃是______色的；有一种治疗近视眼的手术，采用激光对角膜进行处理，使晶状体和角膜构成的透镜对光的偏折能力变得______些（选填“强”或“弱”）．

答案

位于红光外侧的是红外线，位于紫光外侧的是紫外线，它们都属于不可见光，地球上的天然紫外线主要来源于太阳光；

适当的紫外线照射对地球上的生物没有太大的伤害，但过量的紫外线会使人体皮肤粗糙，甚至患上皮肤癌．正是由于大气层中的臭氧层能够吸收大部分的紫外线，才得以保护地球上生物受到紫外线的伤害．

物体能透过所有的色光，这个物体是无色透明的物体．

近视眼是像成在视网膜前，原因是晶状体过厚或眼睛的前后距离过长，若是晶状体过厚，可以对晶状体和角膜构成的透镜进行手术，使其变薄，对光的偏折能力变弱，使成的像后移，直到移到视网膜上．

故答案为：太阳、臭氧、无色、弱．

单项选择题

GFS和Bigtable是依靠（）的存储模型和实现.

A.内存

B.闪存

C.外存（硬盘）

D.光盘存储

完形填空

Tom was a middle-aged leather trader (皮货商) whose repeated failure in career made him a depressed man, often __21_ that he had been cheated by others. One day he told his wife he was so __22__ with the city that he had to leave.
So his family moved to another city. It was the evening of a weekend. When Tom and his wife were busily _23_ up their new home, the light suddenly __24_. Tom was regretful to have forgotten to bring along 25__ and had to wait _26_ in a low mood. Just then he heard light, hesitant 27_ on his door that were clearly audible (听到) in the __28__ night.
“Who’s it?” he wondered, since Tom was a _29__ to this city. And this was the moment he especially hated to be __30__, so he went to the door and opened it __31_. At the door was a little girl, shyly asking, “Sir, do you have candles? I’m your neighbor. ” “No,” answered Tom in anger and shut the door __32__. “What a nuisance (麻烦事)!” He complained over it with his wife. “No sooner had we settled down than the neighbor came to _33__ things.”
After a while, the door was knocked again. He opened it and found the same girl outside. __34_ this time she was _35__ two candles, saying, “My grandma told me the new neighbor downstairs might need candles. She _36_ me here to give you these.” Tom was very _37__ by what he saw. At that moment he suddenly realized what caused his _38__ in life. It was his _39_ and harshness (刻薄) with other people. The person who had cheated him in life was _40__ nobody else but himself, for his eyes had been blurred (蒙蔽) by his unsympathetic （无同情心的）mind.

A．complaining

小题2:A. pleased B disappointed C. exhausted D. encouraged

D．went through

D．flashlights

A．surprisingly

B．delightedly

C．impatiently

D．determination