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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
The best fruit you are able to eat to offer yourself an athletic boost is banana. It comes with a considerable amount of protein, some healthy fat and greater volume of potassium, that's extremely essential for method of getting nutrients to the muscles with the body. Therefore, when after having a workout a sports athlete feels depleted of your energy, the ultimate way to boost it would be to consume a banana or two.
Before discuss nursing position, let us know about the secret: small ears inside the baby's ears into three parts of outer ear, middle ear, inner ear, the middle ear is a relatively sealed chamber, in the front wall there is a small tube connected to the nose pharynx ministry, is called the eustachian tube.
Stainless steel brush filter type: fully automatic stainless steel brush filter, hand-shaking stainless steel brush filter. Its main function is to remove the suspended material in the water, reduce the concentration of suspended material in the water, the particulate matter, reduce turbidity, purify water quality, reduce system dirt, algae, rust, purify water quality, etc.
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