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Dating in central fl xxx

Dating in central fl xxx-63

Fluorocarbon gases are generally greenhouse gases with global-warming potentials 100 to 20,000 times that of carbon dioxide.

Fluorite, the primary mineral source of fluorine which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb meaning "flow" gave the mineral its name. Pharmaceuticals such as atorvastatin and fluoxetine also contain fluorine, and the fluoride ion inhibits dental cavities, and so finds use in toothpaste and water fluoridation. Global fluorochemical sales amount to more than US$15 billion a year. Industrial production of fluorine gas for uranium enrichment, its largest application, began during the Manhattan Project in World War II. Owing to the expense of refining pure fluorine, most commercial applications use fluorine compounds, with about half of mined fluorite used in steelmaking. The rest of the fluorite is converted into corrosive hydrogen fluoride en route to various organic fluorides, or into cryolite which plays a key role in aluminium refining.

Organic fluorides have very high chemical and thermal stability; their major uses are as refrigerants, electrical insulation and cookware, the last as PTFE (Teflon). "Some experiments and observations on the substances produced in different chemical processes on fluor spar".

Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its compounds, and several early experimenters died or sustained injuries from their attempts.

Only in 1886 did French chemist Henri Moissan isolate elemental fluorine using low-temperature electrolysis, a process still employed for modern production. "Solid State Molecular Structures of Transition Metal Hexafluorides".

Haiti's capital of Port-au-Prince lies at the eastern end of the notch-like bay named Canal de Saint-Marc. Satellite radar topographic view of the island of Hispaniola.

The devastating earthquake at Port-au-Prince, Haiti, on 12 January 2010, occurred on the Enriquillo-Plantain Garden fault, visible here as a prominent linear landform immediately southwest of the city of Port-au-Prince and as a series of fault traces extending westward along the full length of the southern Tiburon Peninsula. The northwest peninsula of Haiti and the Gulf of Gonave are visible in this northeast-looking view.

two equal horizontal bands of blue (top) and red with a centered white rectangle bearing the coat of arms, which contains a palm tree flanked by flags and two cannons above a scroll bearing the motto L'UNION FAIT LA FORCE (Union Makes Strength); the colors are taken from the French Tricolor and represent the union of blacks and mulattoes The Caribbean island of Hispaniola, jointly occupied by Haiti and the Dominican Republic, dominates this space station view of the earth.