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Fluorine: A nonmetallic, diatomic gas that is a trace element and member of the halogen family. It is used in dentistry as flouride (FLUORIDES) to prevent dental caries.Fluorine Compounds: Inorganic compounds that contain fluorine as an integral part of the molecule.Halogenation: Covalent attachment of HALOGENS to other compounds.Fluorine Radioisotopes: Unstable isotopes of fluorine that decay or disintegrate emitting radiation. F atoms with atomic weights 17, 18, and 20-22 are radioactive fluorine isotopes.Fluoroacetates: Derivatives of acetic acid with one or more fluorines attached. They are almost odorless, difficult to detect chemically, and very stable. The acid itself, as well as the derivatives that are broken down in the body to the acid, are highly toxic substances, behaving as convulsant poisons with a delayed action. (From Miall's Dictionary of Chemistry, 5th ed)Hydrocarbons, FluorinatedCalcium Fluoride: Calcium fluoride. Occurring in nature as the mineral fluorite or fluorspar. It is the primary source of fluorine and its compounds. Pure calcium fluoride is used as a catalyst in dehydration and dehydrogenation and is used to fluoridate drinking water. (From Merck Index, 11th ed)Fluorides: Inorganic salts of hydrofluoric acid, HF, in which the fluorine atom is in the -1 oxidation state. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Sodium and stannous salts are commonly used in dentifrices.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Fluorocarbons: Liquid perfluorinated carbon compounds which may or may not contain a hetero atom such as nitrogen, oxygen or sulfur, but do not contain another halogen or hydrogen atom. This concept includes fluorocarbon emulsions and fluorocarbon blood substitutes.Wettability: The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.Sodium Fluoride: A source of inorganic fluoride which is used topically to prevent dental caries.Photoelectron Spectroscopy: The study of the energy of electrons ejected from matter by the photoelectric effect, i.e., as a direct result of absorption of energy from electromagnetic radiation. As the energies of the electrons are characteristic of a specific element, the measurement of the energy of these electrons is a technique used to determine the chemical composition of surfaces.3-Deazauridine: 4-Hydroxy-1-(beta-D-ribofuranosyl)-2-pyridinone. Analog of uridine lacking a ring-nitrogen in the 3-position. Functions as an antineoplastic agent.Argon: Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.Agave: A genus known for fibers obtained from their leaves: sisal from A. sisalana, henequen from A. fourcroyoides and A. cantala, or Manila-Maguey fiber from A. cantala. Some species provide a sap that is fermented to an intoxicating drink, called pulque in Mexico. Some contain agavesides.Polyketides: Natural compounds containing alternating carbonyl and methylene groups (beta-polyketones), bioenergenetically derived from repeated condensation of acetyl coenzyme A via malonyl coenzyme A, in a process similar to fatty acid synthesis.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Stainless Steel: Stainless steel. A steel containing Ni, Cr, or both. It does not tarnish on exposure and is used in corrosive environments. (Grant & Hack's Chemical Dictionary, 5th ed)Hydrolyzable Tannins: Polymeric derivatives of GALLIC ACID that are esters of a sugar.Spectrometry, Mass, Secondary Ion: A mass-spectrometric technique that is used for microscopic chemical analysis. A beam of primary ions with an energy of 5-20 kiloelectronvolts (keV) bombards a small spot on the surface of the sample under ultra-high vacuum conditions. Positive and negative secondary ions sputtered from the surface are analyzed in a mass spectrometer in regards to their mass-to-charge ratio. Digital imaging can be generated from the secondary ion beams and their intensity can be measured. Ionic images can be correlated with images from light or other microscopy providing useful tools in the study of molecular and drug actions.Radioisotopes: Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Magnesium Compounds: Inorganic compounds that contain magnesium as an integral part of the molecule.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Isotope Labeling: Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.Romania