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　　A collective term for various equipment used by individuals to prevent damage from toxic agents, biological warfare agents, and radioactive dust. Also known as personal defense equipment. There are mainly: gas masks, gas cloaks, gas gloves, and ga...

　　Many ordinary people know that taking more CT and ultrasound scans can cause radiation to the human body. Naturally, when they hear the new term "nuclear medicine", some people turn pale when talking about it. In fact, nuclear medicine is not a com...

　　What is electromagnetic radiation?　　The interaction between electric and magnetic fields generates electromagnetic waves, and the phenomenon of electromagnetic waves emitting or leaking into the air is called electromagnetic radiation. Electromagne...

　　Examples of electromagnetic radiation hazards to the human body around us:On January 5, 2005, the first electromagnetic radiation health hotline in Sichuan Province was officially opened, and experts and scholars from universities such as the Unive...

　　The various objects that exist in nature, big like planets in the universe and small like cells in the body, are all composed of various different substances.　　Matter is composed of countless small particles, which are called "atoms". Several atoms...