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.
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J.Natn.Sci.Foundation Sri Lanka 2009 37(3):153-165. Phosphate mineral fertilizers, trace metals and human health. C.B.Dissanayake and Rohana Chandrajith*. Department of Geology, Faculty of Science, University of Peradeniya, Peradeniya. Abstract:Fertilizers, indispensable as they may seem, are nevertheless materials that also clearly cause
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· Phosphate rocks are a vital resource for world food supply and security. They are the primary raw material for phosphoric acid and fertilizers used in agriculture, and are increasingly considered to be
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· In Austria, 48 years of very high phosphate fertilization (175 kg P ha −1 year −1) significantly increased the aqua regia soluble trace elements in the soil. Superphosphate application led to a +25%/+22% increase of Cd and a +34%/+21% increase of U in 0–25 cm/25–50 cm soil depth at the Fuchsenbigl site.
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· These heavy metals (Cd, As, Pb, and Hg) exist as impurities and are dependent on the supply of fertilizers, which may be found in natural minerals and phosphate fertilizers (Atafar et al., 2010). The physical and chemical properties of the soil degraded, becoming saltier and forming a crust on top of the soil, reducing the plant’s
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· Phosphate groups are believed to have Lewis base properties, and thus can interact with heavy metal cations that exhibit Lewis acidity through electrostatic attraction and chelation to form highly insoluble metallic
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· Using the available (Nriagu 1974) or predictive thermochemical data, this report explores the role of the formation of base metal phosphates in the dispersion and fixation of the base metals in soils and sediments. Evidence which implicates the formation of insoluble lead phosphates in roadside soils is also considered in detail.
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Phosphorus is often present in lunar rocks and soils in bulk concentrations in excess of 0.5 wt % P205. The minerals apatite and whitlockite account for most of the phosphorus. However, it may also be present in metal grains. The relations between metal particles and the phosphates commonly found adjacent to these particles are investigated, taking into
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· In the present study, this concept of phosphate-metal minerals was applied to Pb Zn mine tailings which were finely textured (mostly < 100 μm in particle size) and rich in heavy metals (Forsyth, 2014). The Pb Ca P
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· Metrics. Phosphate minerals such as those in the apatite group tend to be the dominant forms of phosphorus in minerals on the Earth’s surface. Phosphate can be reduced to phosphides during high
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With metal cations, phosphate forms a variety of salts. These solids are polymeric, featuring P-O-M linkages. When the metal cation has a charge of 2+ or 3+, the salts are generally insoluble, hence they exist as common
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15.2.1 How SrPO 4 coatings are prepared and inhibit initial biodegradation of Mg. Metal phosphate coating is one of the important surface conversion techniques and has been commercially exploited on conventional metals, such as Zn, Fe and steel to improve their lifespan in corrosive environments.
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Indeed, many pegmatitic phosphate minerals have acquired some notoriety because of the rarer trace metals which they tend to accumulate. With the commercialization of phosphate fertilizers since the early part of the 19th century, phosphate minerals have assumed an important role in industrial chemistry and agriculture.
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· HAs demonstrate high affinity for phosphate in wastewater, and they can compete against the active adsorption sites on modified clay minerals (mCMs), thereby inhibiting phosphate removal by mCMs. Moreover, HAs have high polydispersity, and they block the mCM pores, inhibiting the entry of phosphate ions to the internal mCM
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· The environmental impacts associated with the dissolution of phosphate rocks include the release of toxic metals such as U and cadmium (Cd), as well as radionuclides from the 238 U decay series
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· Structural arrangements in selected phosphate minerals based on finite polyhedral clusters: (a) anapaite; (b) schertelite; ( c ) morinite; phosphate tetrahedra are dot-shaded, octahedra are
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· Microbial bioleaching of insoluble metal phosphate minerals is caused by protonation of the anion of the metal compound. In fungi, two mechanisms seem to be the most relevant for solubilization of phosphate minerals: (1) the H + -translocating ATPase of the plasma membrane that is a source of protons, and (2) the production of organic
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:Jerome O. NriaguPublish Year:1984 · Phosphate rock (PR) is an important mineral resource with numerous uses and applications in agriculture and the environment. PR is used in the manufacture of detergents, animal feed, and phosphate (PO43–) fertilizers. Leaching or runoff losses from PR products like PO43– fertilizers, animal feeds, and detergents could cause
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· Phosphate minerals have been shown to possess the potential to adsorb heavy metal ions from aqueous solutions. Of all the inorganic phosphate sources apatites are most readily available. High-grade rock phosphates (> 30% P 2 O 5 ) have already been utilized for the removal of heavy metal ions and have been very effective ( Ma et
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Phosphate Minerals. Phosphate minerals display a great compositional variety, as can be seen from those listed in Table 1. Some examples of common phosphate minerals are
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· Amendments used for HMs in situ immobilization in soil include phosphate compounds, liming materials, metal oxides, clay minerals, organic matter and biochar. As biochar is a new type of carbon material prepared from wood, straw and other organic matter, and contains a certain amount of organic components, it is classified as an OAs
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· Application of phosphate fertilizers not only promoted crop growth, as mentioned above, but also decreased toxic metal content in plant. Figure 2 showed that under application of phosphates to heavy metal-contaminated red soil, the concentration of Pb in rape shoot decreased by 32.6–57.9%, whereas Cd decreased by only 9.8–39.1%.
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· Metal-binding ligands play an important role to plants for the homeostasis of metals and reducing the toxicity thresholds of nonessential metals. A number of metal-binding ligands have now been recognized which help plants to sustain in the hostile environments ( Rauser, 1999 , Callahan et al., 2006 ).
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· Phosphorus makes up about 0.10 percent of the weight of Earth’s crust in the form of phosphate minerals and phosphoruscontaining organic compounds (eg, Mackey and Paytan 2009; Tiessen 2008).
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: Hideo Hashizume · phosphate mineral, any of a group of naturally occurring inorganic salts of phosphoric acid, H 3 (PO 4). More than 200 species of phosphate minerals are recognized, and structurally they
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This chapter presents a review of the physical, chemical and crystallographic properties of phosphate minerals, and discusses their general modes of occurrence. It provides the
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Keywords: Geochemical pathways, heavy metals, mineral fertilizers, superphosphates.doi :10.4038/jnsfsr.v37i3.1219 J.Natn.Sci.Foundation Sri Lanka 2009 37 (3):153-165 Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions
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· Abstract. The availability of phosphorus in soils is controlled by the ability of plants to dissolve phosphate-bearing minerals, including apatite and feldspars. To satisfy the requirement of plants for phosphate, mineral dissolution competes with precipitation such as, for example, reactions involving lead or other heavy metals.
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· Humans are constantly exposed to radioactivity present in rocks, soils, and water, mainly from materials in the Earth’s crust that contain chemical elements belonging to the radioactive series of uranium and thorium. An important anthropogenic source of these natural radioisotopes to the environment is fertilizers, widely used to increase agricultural
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Indeed, many pegmatitic phosphate minerals have acquired some notoriety because of the rarer trace metals which they tend to accumulate. With the commercialization of phosphate fertilizers since the early part of the 19th century, phosphate minerals have assumed an important role in industrial chemistry and agriculture.
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Trituradora de piedra vendida por proveedores certificados, como trituradoras de mandíbula/cono/impacto/móvil, etc.
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