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Moissan's fluorine cell, from his 1887 publication. Fluorine is a relatively new element in human applications. In ancient times, only minor uses of fluorine-containing minerals existed. The industrial use of fluorite, fluorine's source mineral, was first described by early scientist Georgius Agricola in the 16th century, in the context of ...
Their ultimate origin (from biological sources or geological formation) is unclear. [15] The possibility of small amounts of gaseous fluorine within crystals has been debated for many years. One form of fluorite, antozonite, has a smell suggestive of fluorine when crushed. The mineral also has a dark black color, perhaps from free calcium (not ...
Fluorine is a chemical element; ... Trace quantities of organofluorines of uncertain origin have been detected in volcanic eruptions and geothermal springs. [68]
Fluorine, in the form of fluoride, is considered to be a micronutrient for human health, necessary to prevent dental cavities, and to promote healthy bone growth. [28] The tea plant (Camellia sinensis L.) is a known accumulator of fluorine compounds, released upon forming infusions such as the common beverage. The fluorine compounds decompose ...
The history of water fluoridation can be divided into three periods. The first ( c. 1801–1933 ) was research into the cause of a form of mottled tooth enamel called the Colorado brown stain. The second ( c. 1933 –1945) focused on the relationship between fluoride concentrations, fluorosis, and tooth decay, and established that moderate ...
Introducing the carbon–fluorine bond to organic compounds is the major challenge for medicinal chemists using organofluorine chemistry, as the carbon–fluorine bond increases the probability of having a successful drug by about a factor of ten. [30] Over half of agricultural chemicals contain C-F bonds. A common example is trifluralin. [31]
Claudius Galen Guesses At It. Perhaps the most famous doctor to come out of the Roman empire, Claudius Galen acknowledges the clitoris and theorizes that “all the parts, then, that men have, women have too, the difference between them lying in only one thing, namely, that in women the parts are within, whereas in men they are outside.”
Laboratory setup for fluorine reactions, University of Freiburg. Fluorine gas may be stored in steel cylinders where the inside surface is passivated by a metal fluoride layer that resists further attack. [35] [4] Passivated steel will withstand fluorine provided the temperature is kept below 200 °C (392 °F). Above that temperature, nickel is ...