Vacuum engineering
Vacuum technology is a method used to evacuate air from a closed volume by creating a pressure differential from the closed volume to some vent, the ultimate vent being the open atmosphere. When using an industrial vacuum system, a vacuum pump or generator creates this pressure differential. A variety of technical inventions were created based on the idea of vacuum discovered during the 17th century. These range from vacuum generation pumps to X-ray tubes, which were later introduced to the medical field for use as sources of X-ray radiation. The vacuum environment has come to play an important role in scientific research as new discoveries are being made by looking back to the basic fundamentals of pressure. The idea of “perfect vacuum” cannot be realized, but very nearly approximated by the technological discoveries of the early 20th century. Vacuum engineering today uses a range of different material, from aluminum to zirconium and just about everything in between. There may be the popular belief that vacuum technology deals only with valves, flanges, and other vacuum components, but novel scientific discoveries are often made with the assistance of these traditional vacuum technologies, especially in the realm of high-tech. Vacuum engineering is used for compound semiconductors, power devices, memory logic, and photovoltaics.
Vortex tube
The vortex tube was invented in 1931 by French physicist Georges J. Ranque. It was rediscovered by Paul Dirac in 1934 while he was searching for a device to perform isotope separation, see Helikon vortex separation process. German physicist improved the design and published a widely read paper in 1947 on the device, which he called a "Wirbelrohr" (literally, whirl pipe). 
In 1954, Westley published a comprehensive survey entitled ‘‘A bibliography and survey of the vortex tube’’, which included over 100 references. In 1951 Curley and McGree , in 1956 Kalvinskas , in 1964 Dobratz , in 1972 Nash , and in 1979 Hellyar made important contribution to the RHVT literature by their extensive reviews on the vortex tube and its applications.
From 1952 to 1963, C. Darby Fulton, Jr. obtained four U.S. patents relating to the development of the vortex tube. In 1961, Fulton began manufacturing the vortex tube under the company name Fulton Cryogenics. Dr. Fulton sold the company to Vortec, Inc. The vortex tube was used to separate gas mixtures, oxygen and nitrogen, carbon dioxide and helium, carbon dioxide and air in 1967 by Linderstrom-Lang.