|
The rapid development of air filters is closely related to the development of military industry and electronic industry. In the first world war, the use of various chemical agents, asbestos fibre filter paper as the smoke filter layer of military gas masks came into being. The glass fiber filter medium is used in air filtration to obtain a patent in the United States in October 1940. In the 1950s, the United States studied the production process of glass fiber filter paper, and the air filter was improved and developed. In the 1960s, HEPA filters came out; In the 1970s, the filter paper of fine glass fiber was used as the HEPA filter of filter medium, and the filtration efficiency of particle size of 013 micron particle diameter was 99.9998%. Since the eighty s, with the emergence of new test method, use evaluation to improve and to improve the filtering performance requirements, found the HEPA filter there is a serious problem, and he had a higher ULPA filter performance. Countries are still working on it and expect more advanced air filters soon
1 Article
Homeowners are inundated with rising expenses and discovering the most recent strategy to produce free electricity using a magnetic power generator may be useful when you are saving cash on heating expenses. It differs from a solar powered form of generator. Unlike the solar, wind and water sources of generating energy, it is self-perpetuating rather than dependent on external forces.
British Glass is organising a one-day seminar on funding for decarbonisation and energy efficiency work on Thursday 2 November (north of England, venue TBC) – which will be attended by British Glass members’ and non-members.
Sometime in the late 19th century, a forgotten mechanic fastened a primitive engine with a horse drawn wagon creating the initial horseless wagon. The details happen to be lost to history but from that humble beginning, a method of automobile came to be, one that still exercises influence upon us over century later.
New Car Buying Tips--
electric machinery and power system fundamentals download
power plant electrical jobs
hydro electric power commission of ontario
top up electric key online scottish power
shandong tiejun electric power
Copyright ?1998-2017 Technews Corp, All rights reserved
|
