影响炸药爆速的因素有？
参考答案：
1、装药直径的影响成正比
2、装药密度的影响增大装药密度，可使炸药的爆轰压力增大，化学反应速度加快，爆热增大，爆速提高。
3、炸药粒度的影响，减小炸药粒度能够提高化学反应的速度，减小反应时间很反应区厚度，爆速提高。
4、装药外壳的影响，当装药直接较小，爆速远小于理想爆速时，增加外壳可以提高爆速。
5、起爆冲能的影响，要使炸药达到稳定爆轰，必须供给炸药足够的起爆能，激发冲击波速度必须大于炸药的临界爆速。
请认真阅读下面短文,并根据所读内容在文章后的空格内填入最恰当的单词. 每空格1个单词，不得用文章中的单词。 A scientist once said that studying the stars from the earth is something like looking up at the sky from the bottom of a swimming pool. Even on the clearest night the earth’s dense atmosphere will dim stars in the sky as it screens out (遮挡) 30 percent of their light. Air turbulence (湍流) causes stars to winkle. Through a telescope, the stars seem to jump around dizzily. Because the moon has no atmosphere, astronomers are looking forward to setting up an observatory there. On the moon, there will be no clouds to obscure the view. The sky will appear dark at all times, so astronomers can work twenty-four hours a day. Because there is not air turbulence, the stars will steady through a telescope. Because the moon is relatively near the earth, moon-based astronomers will see the stars in familiar patterns known on earth. They will not need new star maps of the sky. Stars seen from the moon will appear to move very slowly. Because the earth rotates (自转) on its axis once every twenty-four hours, earth-based astronomers see the stars hurry across the sky each night. The moon rotates on its axis only once a month. To astronomers on the moon, the stars will appear to stand almost still. Moon-based astronomers will have much more time to focus their telescopes and take time ---exposure photographs. On the earth, man-made radio noises jam the airwaves and interfere with the reception of radio signals from certain stars. A radio telescope located on the far side of the moon will be permanently protected from such interference. It won’t be easy to put telescopes on the moon. However, astronomers are certain the job can be done. They are convinced that the moon is an ideal place to set up an observatory. Title : The Reasons for establishing an observatory on the moon
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