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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
On October 21, 1879, Edison's electric lighting experiment could be regarded as modern technology research
Beijing international automobile exhibition since its inception, the scale expands unceasingly, the exhibition features from the past simple product display, develop to become the enterprise development strategy today distribution and comprehensive image display window; The world's most cutting-edge technology innovation information exchange platform; The most efficient brand promotion stage. The quality of the exhibits has been improved, and the impact is also becoming more and more widespread. Many multinational auto companies have listed the Beijing auto show as the global a-level auto show. Receives exhibits fine and brand, the international exhibition concept and characteristic, the Beijing auto show has become the brand of has higher popularity in the international exhibition, for the development of China's automobile industry, the establishment and development of independent brands play an important role, and to promote exchange and cooperation of Chinese and foreign automobile industry, for the rapid development of Chinese exhibition economy has made a positive contribution
When you receive your copilot license, you accept certain responsibilities and agree to try taking a little actions while you're sitting in the passenger seat. For one thing, you agree to collaborate with all the driver in efforts to keep up road concentration, in addition to safety vigilance. This means that you have to be vigil all the time and become mindful of the conditions on the road and warn the driving force of the potential dangers that could jeopardize your safety. Furthermore, you might be in charge of helping the trucker avoid all sorts of distractions, like adjusting certain devices in a car, or another technical matters, along with giving assistance during parking or lane changes. If the driving force has to make use of the GPS, adjust the car stereo, or the vehicle's air conditioning, you must do that rather than them, so that they can keep their on the job the tyre as well as their eyes on the highway.
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