空气包为什么能基本稳定压力和流量，其原理是什么？
参考答案：
吸入空气包和排出空气包都是一个内部充以一定压力的氮气或空气的密闭容器，其基本功能是利用气体的可压缩性，随着吸入压力和排出压力的变化，自动地向泵（吸入时）或排出管（排出时）供给液体，或者储存一部分来自吸入管（吸入时）或泵（排出时）的液体，使吸入总管内或排出总管内液流均匀，惯性力减小，从而降低压力波动。
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| Tolstoy, the great Russian writer, liked to walk about in a railway station near his home. One day when he was walking up and down as 1 , looking at people getting on and off the 2 , he heard a lady 3 after him, "Hey, you old fellow, go and bring back my handbag in the 4 room which I 5 there." Tolstoy 6 there. He 7 the bag up and walked quickly along the platform. At the same time the lady was waiting beside the carriage, looking 8 . When at last the old man gave the bag back to her, she opened it to 9 sure nothing was 10 .""Good, old man." said the woman. "You are just as quick as I can expect. Here you are."She gave a copper coin to him. Tolstoy 11 the coin and put it into his pocket with a smile. But the woman was very 12 when she heard he was Tolstoy, the author of the great novel WAR AND PEACE. She returned to Tolstoy and said,"Oh, excuse me... Oh, how silly I was to 13 you as a porter. Please throw back that coin if you forgive me." "Oh, madam, why? You have done 14 wrong." Tolstoy laughed."The coin is given for my work, so I 'll 15 it. Thank you, madam!" | ||||
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