If you need to create a high vacuum, there are basically two options: turbomolecular pumps and diffusion pumps. Turbomolecular pumps require rotors spinning at many thousands of rotations per minute ...
一些您可能无法访问的结果已被隐去。
显示无法访问的结果一些您可能无法访问的结果已被隐去。
显示无法访问的结果