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Fluorine biology is also relevant to a number of cutting-edge technologies. PFCs (perfluorocarbons) are capable of holding enough oxygen to support human liquid breathing. Organofluorine in the form of its radioisotope 18 F is also at the heart of a modern medical imaging technique known as positron emission tomography (PET).
Chemically, it is 2-deoxy-2- [18F]fluoro-D-glucose, a glucose analog, with the positron -emitting radionuclide fluorine-18 substituted for the normal hydroxyl group at the C-2 position in the glucose molecule. The uptake of [18 F]FDG by tissues is a marker for the tissue uptake of glucose, which in turn is closely correlated with certain types ...
Fluorine. cubic. Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen [note 1] and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases.
Fluorine compounds. Fluorine forms a great variety of chemical compounds, within which it always adopts an oxidation state of −1. With other atoms, fluorine forms either polar covalent bonds or ionic bonds. Most frequently, covalent bonds involving fluorine atoms are single bonds, although at least two examples of a higher order bond exist. [2]
Fluoride or fluorine deficiency is a disorder which may cause increased dental caries [1] and possibly osteoporosis, [2] [3] due to a lack of fluoride in diet. [ 4 ] [ 5 ] Common dietary sources of fluoride include tea, grape juice, wine, raisins, some seafood, coffee, and tap water that has been fluoridated . [ 6 ]
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 smelting. The name "fluorite" (and later "fluorine ...
As a result, the physical and chemical properties of organofluorines can be distinctive in comparison to other organohalogens. The carbon–fluorine bond is one of the strongest in organic chemistry (an average bond energy around 480 kJ/mol [ 1 ]). This is significantly stronger than the bonds of carbon with other halogens (an average bond ...
About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium. All 11 are necessary for life. The remaining elements are trace elements, of which more than a dozen are ...