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Soil particles can be classified by their chemical composition as well as their size. The particle size distribution of a soil, its texture, determines many of the properties of that soil, in particular hydraulic conductivity and water potential, [1] but the mineralogy of those particles can strongly modify those properties. The mineralogy of ...
The amounts of the manganese and antimony activators vary between 0.05 and 0.5 mole percent. The reaction used to create halophosphor is shown below. The antimony and manganese must be incorporated in the correct trace amounts if the product is to be fluorescent. 6 CaHPO 4 + (3+x) CaCO 3 + (1−x) CaF 2 + (2x) NH 4 Cl → 2 Ca 5 (PO 4) 3 (F 1 ...
Cubic crystals up to 20 cm across have been found at Dalnegorsk, Russia. [23] The largest documented single crystal of fluorite was a cube 2.12 meters in size and weighing approximately 16 tonnes. [24] Fluorite on barite from the Berbes mine, Ribadesella, Asturias (Spain). Fluorite crystal, 2.2 cm.
Fluoride is classified as a weak base since it only partially associates in solution, but concentrated fluoride is corrosive and can attack the skin. Fluoride is the simplest fluorine anion . In terms of charge and size, the fluoride ion resembles the hydroxide ion.
The individual crystals of montmorillonite clay are not tightly bound hence water can intervene, causing the clay to swell, hence montmorillonite is a characteristic component of swelling soil. The water content of montmorillonite is variable and it increases greatly in volume when it absorbs water.
Structural and thermodynamic properties of crystal hexagonal calcium apatites, Ca 10 (PO 4) 6 (X) 2 (X= OH, F, Cl, Br), have been investigated using an all-atom Born-Huggins-Mayer potential [42] by a molecular dynamics technique. The accuracy of the model at room temperature and atmospheric pressure was checked against crystal structural data ...
Calcium fluoride is a classic example of a crystal with a fluorite structure. Crystallographic information can be collected via x-ray diffraction, providing information on the locations of electron density within a crystal structure. Using modern software such as Olex2, [4] one can solve a crystal structure from crystallographic output files.
EuF 2 can be used to dope a trivalent rare-earth fluoride, such as LaF 3, to create a vacancy-filled structure with increased conductivity over a pure crystal. Such a crystal can be used as a fluoride-specific semipermeable membrane in a fluoride selective electrode to detect trace quantities of fluoride.