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The Creation of Ultrahigh Vacuum

Early in the 17th century, there was still vigorous disagreement as to the feasibility of empty space Descartes denied the possibility of a vacuum. The matter was put to the test for the first time by Otto von Guericke (1602-1686), a German politician who devoted his brief leisure to scientific experimentation (Krafft 1970-1980). He designed a crude suction pump using a cylinder and piston and two flap valves, and [Pg.404]

With the rotary and diffusion pumps in tandem, aided by a liquid-nitrogen trap, a vacuum of 10 Torr became readily attainable between the wars by degrees, as oils and vacuum greases improved, this was inched up towards 10 Torr (a hundred-billionth of atmospheric pressure), but there it stuck. These low pressures were beyond the range of the McLeod gauge and even beyond the Pirani gauge based on heat conduction from a hot filament (limit Torr), and it was necessary to [Pg.405]

Such vessels can also be baked at a temperature of several hundred degrees, to drive off any gas adsorbed on metal surfaces. The pumping function of an ion gauge was developed into efficient ionic pumps and turbomolecular pumps , supplemented by low-temperature traps and cryopumps. Finally, sputter-ion pumps, which rely on sorption processes initiated by ionised gas, were introduced. A vacuum of 10 -10 Torr, true UHV, became routinely accessible in the late 1950s, and surface science could be launched. [Pg.406]

An early account of UHV and its requirements is by Redhead et al. (1962) an even earlier summary of progress in vacuum technology, with perhaps the first tentative account of UHV, was by Pollard (1959). A lively popular account is by [Pg.406]

Steinherz and Redhead (1962), while advances in vacuum techniques from a specifically chemical viewpoint were discussed by Roberts (1960). [Pg.407]


See other pages where The Creation of Ultrahigh Vacuum is mentioned: [Pg.391]    [Pg.404]   


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