Caesium phosphide formula12/3/2023 The Permian Phosphoria Formation of the western United States represents some 15 million years of sedimentation. Phosphorites are known from Proterozoic banded iron formations in Australia, but are more common from Paleozoic and Cenozoic sediments. Peloidal or pelletal phosphorites occur normally whereas oolitic phosphorites are not common. Phosphatic grains may be accompanied by organic matter, clay minerals, silt-sized detrital grains, and pyrite. This means that their textures are similar to that of collophane, or fine micrite-like texture. There are some phosphorites that are very small and have no distinctive granular textures. They also can be composed of peloids, ooids, fossils, and clasts that are made up of apatite. These layers contain the same textures and structures as fine-grained limestones and may represent diagenetic replacements of carbonate minerals by phosphates. Phosphatic sedimentary rocks are commonly accompanied by or interbedded with shales, cherts, limestone, dolomites and sometimes sandstone. Although these thick beds can exist, they are rarely only composed of phosphatic sedimentary rocks. Phosphate-rich sedimentary rocks can occur in dark brown to black beds, ranging from centimeter-sized laminae to beds that are several meters thick. Limestones and mudstones are common phosphate-bearing rocks. Phosphorite deposits often occur in extensive layers, which cumulatively cover tens of thousands of square kilometres of the Earth's crust. Other sources also include chemically dissolved phosphate minerals from igneous and metamorphic rocks. It is also present as hydroxyapatite Ca 5(PO 4) 3OH or Ca 10(PO 4) 6(OH) 2, which is often dissolved from vertebrate bones and teeth, whereas fluorapatite can originate from hydrothermal veins. The phosphate is present as fluorapatite Ca 5(PO 4) 3F typically in cryptocrystalline masses (grain sizes < 1 μm) referred to as collophane-sedimentary apatite deposits of uncertain origin. By comparison, the average phosphorus content of sedimentary rocks is less than 0.2%. This occurs through washing, screening, de-liming, magnetic separation or flotation. Marketed phosphate rock is enriched ("beneficiated") to at least 28%, often more than 30% P 2O 5. The phosphate content of phosphorite (or grade of phosphate rock) varies greatly, from 4% to 20% phosphorus pentoxide (P 2O 5). Phosphorite, phosphate rock or rock phosphate is a non- detrital sedimentary rock that contains high amounts of phosphate minerals. Fossiliferous peloidal phosphorite, (4.7 cm across), Yunnan Province, China. Experiments described in this paper have allowed the development of a structural model of the β-CN(1-25)-amorphous calcium phosphate nanocomplex.Sedimentary rock containing large amounts of phosphate minerals Peloidal phosphorite, Phosphoria Formation, Simplot Mine, Idaho. Total correlation spectroscopy and nuclear Overhauser effect spectroscopy spectra were acquired and sequentially assigned. (1)H NMR spectra were well resolved, and (3)JH(N)-H(α) measurements ranged from a low of 5.5 Hz to a high of 8.1 Hz. Translational diffusion measurements indicated that the β-CN(1-25)-ACP nanocomplex has a hydrodynamic radius of 1.526 ± 0.044 nm at pH 6.0, which increases to 1.923 ± 0.082 nm at pH 9.0. We have studied the structure of the complexes formed by the CPP with calcium phosphate using a variety of nuclear magnetic resonance (NMR) techniques. The calcium phosphate in these complexes is biologically available for intestinal absorption and remineralization of subsurface lesions in tooth enamel. The CPP stabilize calcium and phosphate ions through the formation of complexes. Tryptic digestion of the calcium-sensitive caseins yields casein phosphopeptides (CPP) that contain clusters of phosphorylated seryl residues.
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