Air pumps are involved, but their role is limited to creating a partial vacuum in the pipes in order to reduce resistance to the capsules' movement.

也使用气泵，但作用仅限于在管道中制造半真空，以减小胶囊运行的阻力。

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The placement of the glass cup creates a partial vacuum, which is believed to stimulate muscles and blood flow, while relieving pain.

这种放置方法会形成部分真空，据说这样能舒展肌肉，促进血液流通，从而缓解疼痛。

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The flow resistance device is a important unit for achieving electron beam welding in partial vacuum.

气阻装置是实现低真空电子束焊接的重要部件。

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At certain points during the screening I attended, when the action was interrupted by major eruptions of information, a sealed chamber under partial vacuum might have described the screening room.

WSJ: Plot's Knots Bedevil 'Angels & Demons'

Among the movie's many revelations is the fact -- I'm taking the factuality on faith -- that the Vatican library's most treasured manuscripts are stored in sealed chambers under a partial vacuum.

WSJ: Plot's Knots Bedevil 'Angels & Demons'