If air weren't admitted into the bell jar the electric bell in the bell jar would not ring because of a lack of a medium.
如果我们不让空气进入铃罩，铃罩中的电铃一定会因缺少介质而不响了。
If air weren't admitted into the bell jar, the electric bell in the bell jar would not ring because of a lack of a medium.
如果我们不让空气进入铃罩，铃罩中的电铃一定会因缺少介质而不响了。
A toughness cushion ring is arranged at the bottom of the threaded column on the jar lid.
在坛盖上螺纹拄的底部，有一韧性垫圈。
The utility model comprises a jar body, a jar lid, an air hole, a cushion ring, internal screw threads and external screw threads.
本实用新型由坛体、坛盖、透气孔、垫圈、内螺纹和外螺纹构成。
The utility model comprises a jar body, a jar lid, an air hole, a cushion ring, internal screw threads and external screw threads.
本实用新型由坛体、坛盖、透气孔、垫圈、内螺纹和外螺纹构成。
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