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Tensile strength
Tensile strength measures the force required to pull something such as rope, wire, or a structural beam to the point where it breaks. The tensile strength of a material is the maximum amount of ... > more -
Polychlorinated biphenyl
Polychlorinated biphenyls (PCBs) are a class of organic compounds with 1 to 10 chlorine atoms attached to biphenyl. Although the physical and chemical properties vary widely across the class, PCBs ... > more -
Nitrogen oxide
NOx is a generic term for the various nitrogen oxides produced during combustion. They are believed to aggravate asthmatic conditions, react with the oxygen in the air to produce ozone, which is also ... > more -
Ultrasound
Ultrasound is sound with a frequency greater than the upper limit of human hearing, approximately 20 kilohertz (20,000 hertz). Some animals, such as dogs, dolphins, bats, and mice have an upper limit ... > more
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