| 单词 |
preliminary vacuum |
| 释义 |
Preliminary Vacuum Preliminary Vacuum (Russian forvakuum), the state of a gas at pressures from 1 to 10–3 mm Hg (102-10–1 newtons per m2), produced in a vacuum system by special pumps prior to the activation of high-vacuum pumps and maintained at the outlet of the latter (seeVACUUM TECHNOLOGY and VACUUM PUMP). |
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