高温、高压、低温、低压是近代新兴的四门边缘科学技术。低压即真空技术。它出世于二十世纪初,到四十年代后才有了飞速的发展。随着原子能、半导体、宇宙航行、电子计算技术的发展,真空技术有了迅速的发展,而且成为实现四大尖端技术必不可少的重要手段。真空技术在国民经济中的 High temperature, high pressure, low temperature, low pressure is a new four-edge science and technology in modern times. Low pressure is vacuum technology. It was born in the early twentieth century and developed rapidly after the forties. With the development of atomic energy, semiconductors, astronautics and electronic computing technology, vacuum technology has developed rapidly and has become an indispensable and important means of realizing the four cutting-edge technologies. Vacuum technology in the national economy