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Dry chemical powder is used on all classes of fires. Dry chemical powder puts out the fire by coating the burning material with a thin layer of dust, thereby separating the fuel from the oxygen in the air. The powder also works to interrupt the chemical reaction of fire, so these extinguishers are extremely effective at putting out the fire.
Between 1913 and 1950 radium-228 and radium-226 were used to activate a phosphor made of silver doped zinc sulfide (ZnS:Ag), which gave a greenish glow. The phosphor is not suitable to be used in layers thicker than 25 mg/cm 2, as the self-absorption of the light then becomes a problem. Furthermore, zinc sulfide undergoes degradation of its ...
This multipurpose grenade was mostly used for signaling, smoke screens, and inflammation; it could also cause severe burns and had a psychological impact on the enemy. [129] Military uses of white phosphorus are constrained by international law. 32 P and 33 P are used as radioactive tracers in biochemical laboratories. [130]
Tritium is the only radiation source used in radioluminescent light sources today due to its low radiological toxicity and commercial availability. [3] Various preparations of the phosphor compound can be used to produce different colors of light. For example, doping zinc sulfide phosphor with different metals can change the emission wavelength ...
Hercules, Inc. was a chemical and munitions manufacturing company based in Wilmington, Delaware, United States, incorporated in 1912 as the Hercules Powder Company following the breakup of the DuPont explosives monopoly by the U.S. Circuit Court in 1911. [1]
The term phosphor had been used since the Middle Ages to describe minerals that glowed in the dark. One of the most famous, but not the first, was Bolognian phosphor. Around 1604, Vincenzo Casciarolo discovered a "lapis solaris" near Bologna, Italy. Once heated in an oxygen-rich furnace, it thereafter absorbed sunlight and glowed in the dark.
Europium(III) oxide (Eu 2 O 3), is a chemical compound of europium and oxygen.It is widely used as a red or blue phosphor in television sets and fluorescent lamps, and as an activator for yttrium-based phosphors.
It is also used as a green phosphor in projection CRTs, though its drawback is marked lowering of efficiency at higher temperatures. Variants include, for example, using praseodymium instead of terbium ( CAS registry number 68609-42-7 , EINECS number 271-826-9), or using a mixture of dysprosium and terbium for doping (CAS number 68609-40-5 ...