味精生产中无菌压缩空气的作用是什么？

简述固定支承、可调支承、自位支承、辅助支承的特点。

The first time Luca heard the Island of Inventions, he was very young, but the wonders he heard about sounded so unbelievable to him that they were forever kept in his memory. Since then, he never stopped searching clues which might lead him to that place of wonder. He read widely to collect information.

Taking a little from here and there, he got quite a clear idea of what the Island was really like. It was a secret place, where all the great men learn and invent together. To be able to join that select club, you had to have created great inventions. Only then could you receive the invitation.

To get a chance, Luca spend the years studying and inventing. Every new idea he got, he made it into an invention, and if there were anything he didn’t understand, he would seek help. Soon he met other brilliant inventors too, and he told them of the secrets of the Island. These young inventors would likewise dream of being sent “the letter”.

As time passed, the disappointment of not being sent the letter gave rise to even greater cooperation and help between them. Their inventions soon became known throughout the world.

But no invention came.

They didn’t lose heart. They continued learning and inventing, trying to come up with better ideas. Fresh talent was added to their group. One day, Luca, already very old, was speaking with a brilliant young man who had written to join their group. Luca told the young man the secrets of the Island, and of how he was sure that they would receive an invitation. Surprised, the young inventor said: “What? You mean this isn’t really the Island of Inventions?”

It inspired Luca and he realized that his dream had become true.

小题1:Luca read widely to ________.

A．get information about the great inventions

B．get clear ideas about the island for vacations

C．seek massages about the secret club of inventions

D．get more knowledge for the benefit of his inventions小题2:Luca and other brilliant inventors around him shared a dream of _______.

A．being great inventors of worldwide fame

B．being accepted as members of the Island of Inventions

C．being inventors envied by members of the Island of Inventions

D．being remembered for the contribution to scientific development小题3:What is the effect of their not being given “the letter”?

A．They were disappointed, while it encouraged them to work harder.

B．They became desperate and decided to have another way of living.

C．They changed their strategy and promote their inventions publicly.

D．They gave up their dream while continued their inventions together.

某客户每天要进行备份的应用多达25个，每个应用需要备份的数据量都不大。之前采用物理磁带库进行数据备份，配置了2个LTO3的磁带驱动器。据用户反映，目前存在备份窗口内无法完成备份任务的问题。在这种情况下，推荐用户怎样解决当前问题？（）

A.将LTO3磁带驱动器替换为LTO4

B.再增加2个LTO4磁带驱动器

C.增加磁带槽位

D.推荐用户使用虚拟带库提高并行备份任务数

液压马达和液压泵从原理上讲具有可逆性，有的既可当泵用，又可当马达用。

在不影响使用功能的情况下，易接近的机械零部件应避免（）、粗糙的表面、穿出部分和可能刮伤身体部分或衣服的开口。尤其应注意金属薄片的棱边必须倒钝、折边或修边。可能引起”刮”伤的开口管端应包覆

A.复杂形状

B.锐边尖角

C.鲜明颜色

D.材质坚硬