问题 问答题 简答题

水内冷汽轮发电机并列后,对长负荷的速度应考虑哪些因素?

答案

参考答案:

并列后,长负荷的速度除要考虑汽轮机和锅炉的因素外,还要考虑:①使各部件发热膨胀均匀;②应使定子端部的周期性振动缓慢增加,以保证水接头及绝缘引水管有一逐渐适应的过程,避免突然发生振动使接头焊缝开裂,造成漏水故障;③由于水内冷发电机电磁负荷大,负荷上升速度过快,会使定子端部绕组造成很大的冲击力,所以要控制并列后加负荷的速度。

选择题
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Blind photography sounds strange.But a striking exhibition of photographs in California argues that it develops as a result of the contemporary art.The show "Sight Unseen", at the California Museum of Photography until Aug.29, includes everything: underwater scenes, landscapes, abstracts and everything else you might expect from a "sighted" photographer.

How do the blind take their photographs? Some rely on assistants to set up and then describe the shots (镜头) , and others just point and shoot in the right place."Just like any good artists," says McCulloh."They have their unique ways of operating." One participating photographer is Pete Eckert, an artist with multiple degrees in design and sculpture who only turned to photography after losing his vision in the mid-1990s.He opens the shutter (快门) on his camera and then uses flashlights, lights, and candies to paint his scene on film.A former fashion photographer in Chicago, Weston, lost his vision due to AIDS in 1996 and focuses on images of destruction and disability.His photos are also a star of the show.

What do gallery-goers say? "I was very impressed by it.The technique and experience was amazingly different," says John Hesketh, a printmaker in Anaheim."You never have a sense of feeling sorry for these people because they've worked very hard to prove their value."

Beyond the praise, however, the exhibition also makes a great example for disabled people everywhere.That point was explained in early May during a discussion on the TV show.At the very end of the talk, one attendee expressed his opinion."This exhibition is extraordinary and revolutionary for many reasons.I think that by being an artist with a disability, you are continuing the work of those people who fought for basic civil rights to gain access and to have a voice.In that way, it's so wonderful that your photographs say it all."

63.From the passage we know that some blind people take photos by______

A.describing the things to their assistants

B.holding the camera and shooting randomly

C.opening the shutter with the help of others

D.using special equipment designed for them

64.We can learn from the passage that blind photographers ______

A.were not born blind               B.do jobs related to art

C.focus on different subjects           D.like photos of destruction

65.What is people's reaction to the blind photography show?

A.They admire the blind photographers' hard work.

B.They feel really sorry for those blind photographers.

C.They think some have good techniques while others not.

D.They can understand the real meaning of each photograph.

66.The significance of the exhibition lies in the fact that ______.

A.the California Museum of Photography receives praises for holding the show

B.the public have a chance to know what the blind people are concerned about

C.the blind photographers have a good place to show their works

D.the exhibition can be very inspiring to the blind in the world