The parameters of unit cell, structure, refractive index, solubility data, PO4/CO3 ratio, surface area, etc., are important parameters for characterization of phosphate rocks. Third chapter of this book …

Apatite ( Fig. 1.12) is a group of natural calcium mineral±fluorine and chlorine (Ca 5 (PO 4) 3 (F, Cl, OH)). The mineral primarily occurs as phosphate rock. The large apatite deposits are located in China, Canada, the United States, Europe, Russia, and India. Apatite is used as a source of phosphorus, phosphoric acid, and fertilizers.

Illustration of apatite formation in two distinct contexts: (a) Homogeneous nucleation by precipitation, where an aqueous solution comprising phosphate ions are …

Calcium phosphate apatites offer outstanding biological adaptability that can be attributed to their specific physico-chemical and structural properties. The aim of this review is to summarize and discuss the specific characteristics of calcium phosphate apatite biominerals in vertebrate hard tissues (bone, dentine and enamel). Firstly, the …

Cu-containing, apatite-type phosphate–silicate solid solutions, Lax Ca10−x (PO4)6−x (SiO4)x Cuy Oz (x = 3, 5, and 6), were synthesized by an impregnating method into the channels of apatite ...

Data input. For this paper, we will build upon our earlier work on the apatite family of crystal structures 16.The apatite crystal structure has the general formula of A 5 (BO 4) 3 X, with A ...

apatite. An apatite crystal excavated in Durango, Mex. Apatite is a member of a group of structurally related minerals having compositions symbolized A5 ( B O 4) 3X, in which A is a metal, …

Indeed, some evidence suggests that much apatite formation may proceed through the production of kinetically labile precursors like octacalcium phosphate or other amorphous phases (Morse and Casey ...

Phosphate, (MAP), NH4(H2PO4), Di-Ammonium Phosphate (DAP), (NH4)2HPO4, are produced by the reaction of ammonia on phosphoric acid solution. The slurry is then …

Weyl points and spin-orbit coupling in copper-substituted lead ...

Apatite is the most abundant phosphate mineral which include more than 95% of al phosphorus in the Earth´s crust. The seventh chapter of this book provides brief description of sedimentary and igneous phosphate rocks and introduces basic ideas for characterization and classification of phosphate rocks. The chapter continues with …

The 2D 31 P-13 C DCP spectrum shown in Fig. 8a exhibits cross peaks between crystalline apatite phosphate resonance at 2.8 ppm (along the vertical axis) ... de Bruyn, J. R. et al. Dynamic ...

Apatite is the mineral used for the hardness of 5 in the Mohs Scale. It is popular as a gemstone. Its most important uses are in the production of fertilizer and phosphoric acid for the chemical industry. ... Apatite is the name of a group of phosphate minerals with similar chemical compositions and physical properties. They are an important ...

1. Introduction. Biological apatite is an inorganic calcium phosphate salt (CaPs) in apatite form with a biological derivation. As the main inorganic component of both bones and teeth, it is distributed in the organic constituents with certain sequence and direction [].By serving as the fillers in such biological tissues, biological apatite is critical …

La solution de calcium est versée dans la solution d'ions phosphate et carbonate. L'excès de ces ions permet de tamponner la solution à un pH physiologique …

Croissance de cristal in vivo additifs biologiques 10 mM de Ca2+ et CO32- → CaCO3 Quand on ajoute des additifs biologiques, ça change complètement le processus de minéralisation. La structure et la croissance ne sont pas homogènes, le cristal va se déformer. Les molécules biologiques interfèrent sur la croissance du cristal.

Several sequential processes occurring during thermal treatment of biological apatite from mineralized tissues can be attributed to the following temperature …

Various other complex ions have been inferred and/or reported to be part of the biological apatite's crystal lattice, such as "labile CO 3 2− ", "non-apatitic CO 3 2− ", "labile PO 4 3− ", "labile HPO 4 2− ", and "non-apatitic HPO 4 2− " (e.g., [30], [34], [43], [44], [45]).In contradiction to the claims that these ionic entities are part of the crystalline bone ...

Abstract. Biological apatite is an inorganic calcium phosphate salt in apatite form and nano size with a biological derivation. It is also the main inorganic …

Abstract Apatite calcium phosphates have been synthesized at pH 9–11, Ca/P = 1.50–1.67 under variable isolation conditions. A complex procedure for identification of inclusion of amorphous calcium phosphate by precipitation of hydroxyapatite under non-equilibrium conditions, including XRD/FTIR/DTA methods. The maximal stabilization of …

A Review of Rare-Earth Elements Extraction with Emphasis on Non-conventional Sources: Coal and Coal Byproducts, Iron Ore Tailings, Apatite, and Phosphate Byproducts

2.1.1. Igneous apatite geochemistry. In magmatic rocks apatite is a minor yet ubiquitous accessory phase. Apatite is occasionally a rock forming mineral in some cumulates and rare igneous rock types such as nelsonites and certain pegmatites (Piccoli and Candela, 2002), while it may be absent in some S-type granitoids in which the high solubility of …

Using a bone-mimetic, apatite-polymer nanocomposite, we have studied the initial crystallisation steps during the transformation …

In order to define the role of fluids in the formation of (Y + REE) phosphate minerals associated with apatite, a series of experiments covering a wide ranges of temperature (900−300 oC) and ...

Apatite is the most common phosphate mineral, and is the main source of the phosphorus required by plants. The bones and teeth of most animals, including humans, are composed of calcium phosphate, which is the same material as Apatite. (These biological Apatites are almost exclusively the Hydroxylapatite type.) Chemical Formula.

Among possible precursors, amorphous calcium phosphate (ACP) and octacalcium phosphate (OCP, triclinic) are two potential candidates [29, 34] that have already been suggested as precursors of bone-apatite in vivo [35, 36]. After their formation, both compounds may then be hydrolyzed to apatite in a subsequent step.

A scheme of formation and thermal transformations of apatitic calcium phosphates under different equilibrium and formation conditions has been suggested …

EMI-S4-GPI -NADIFI Abderrahim Procédés Industriels 1 Synthèse de l'acide phosphorique par voie humide Généralités septembre 2015 A.Nadifi 1 Vue d'ensemble usines acide sulfurique – Utilités - acide phosphorique - engrais septembre 2015 A.Nadifi 2 septembre 2015 A.Nadifi 3 Généralités 1/ Les phosphates Le phosphore élément indispensable à la …

Calcium phosphate apatites are inorganic compounds encountered in many different mineralized tissues. Bone mineral, for example, is constituted of …

Reimphoto / Getty Images Apatite (Ca 5 (PO 4) 3 F) is a key part of the phosphorus cycle. It is widespread but uncommon in igneous and metamorphic rocks. Apatite is a family of minerals centered around fluorapatite, or calcium phosphate with a bit of fluorine, with the formula Ca 5 (PO 4) 3 F. Other members of the apatite group have …

Hydroxyapatite (HA) was prepared by stirring amorphous calcium phosphate (ACP), which contained occluded Cl− as a tracer ion, in distilled water buffered to pH 7.4 by tris-HCl at 25, 37, 60, 80 and 100°. HA made in this manner contained from less than 1% (25°) to 11% (100°) of the amount originally occluded in the precursor ACP. These results suggest …

Using FTIR spectroscopy, Coscas et al. [195] have demonstrated that free DNA could be involved in arterial calcification formation by precipitating calcium phosphate apatite crystals in the vessel ...

Apatite is the name given to a group of phosphate minerals, usually referring to hydroxylapatite (or hydroxyapatite), fluoroapatite (or fluorapatite), and chloroapatite (or chlorapatite).They are named for the presence of hydroxide (OH-), fluoride (F-), and chloride (Cl-) ions, respectively, in the crystal lattice. These three forms of apatite are …