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Bone-ash

Industrially. phosphoric(V) acid is manufactured by two processes. In one process phosphorus is burned in air and the phos-phorus(V) oxide produced is dissolved in water. It is also manufactured by the action of dilute sulphuric acid on bone-ash or phosphorite, i.e. calcium tetraoxophosphate(V). Ca3(P04)2 the insoluble calcium sulphate is filtered off and the remaining solution concentrated. In this reaction, the calcium phosphate may be treated to convert it to the more soluble dihydrogenphosphatc. CafHjPOjj. When mixed with the calcium sulphate this is used as a fertiliser under the name "superphosphate . [Pg.246]

Bone-ash, calcium phosphate, is used to create fine chinaware and to produce mono-calcium phosphate, used in baking powder. [Pg.37]

Bone ash Bone black Bone cement Bone coal Bone density... [Pg.121]

The fire assay, the antecedents of which date to ancient Egypt, remains the most rehable method for the accurate quantitative determination of precious metals ia any mixture for concentrations from 5 ppm to 100%. A sample is folded iato silver-free lead foil cones, which are placed ia bone-ash cupels (cups) and heated to between 1000 and 1200°C to oxidize the noimoble metals. The oxides are then absorbed iato a bone-ash cupel (ca 99%) and a shiny, uniformly metaUic-colored bead remains. The bead is bmshed clean, roUed fiat, and treated with CP grade nitric acid to dissolve the silver. The presence of trace metals ia that solution is then determined by iastmmental techniques and the purity of the silver determined by difference. [Pg.85]

Knochen-asche,/. bone ash. -band, n. (Anat.) ligament. [Pg.248]

Treib-alkohol, m. power alcohol, -arbeit, /. cupellation. -asche, /. cupel ashes, bone ash. -brhhe,/. Tech.) old liquor, -eiscn, n. white pig iron,... [Pg.451]

Nineteen bone samples were prepared for analysis of the trace elements strontium (Sr), rubidium (Rb), and zinc (Zn). The outer surface of each bone was removed with an aluminum oxide sanding wheel attached to a Dremel tool and the bone was soaked overnight in a weak acetic acid solution (Krueger and Sullivan 1984, Price et al. 1992). After rinsing to neutrality, the bone was dried then crushed in a mill. Bone powder was dry ashed in a muffle furnace at 700°C for 18 hours. Bone ash was pressed into pellets for analysis by x-ray fluorescence spectrometry. Analyses were carried out in the Department of Geology, University of Calgary. [Pg.5]

The element phosphorus, like nitrogen, is essential to plant and animal life. Although phosphorus was not identified and isolated until 1669, phosphorus-containing materials have been used as fertilizers since ancient times, usually from bird droppings, fish, and bone. The first phosphoric acid was made by treating bone ashes with sulfuric acid. This marked the beginning of the commercial fertilizer industry. Eventually, mined phosphate rock, a poor fertilizer by itself, was substituted for bones as a raw material for phosphoric acid in the mid-1880s. [Pg.25]

Chorionic gonadotropin. Follicle stimulating hormone Urea, Uric add. Bilirubin, Cortisol, n-Maimitol. n-Glucose, Sodium pyruvate, 4-hydroxy-3-methoxy mandelic add, 4-Nitro-phenol, 17 Amino adds in HQ, Angiotensin-I, Tripahnitin, Bone meal (8 elements), Bone ash (8 elements), lithium carbonate Luteinizing hormone. Thyroid stimulating hormone... [Pg.210]

Precious metals such as silver and gold, which are seldom oxidized even at high temperatures, are often refined by cupellation, a process for removing from them base metal impurities such as lead and tin, with which they are associated in many ores. Hot lead and tin are easily oxidized. In the cupellation process, a crude, impure precious metal is placed in a shallow cup or crucible made of bone ash, known as a cupel, and is then heated by a blast of hot air. At high temperatures, the base metal impurities are oxidized by oxygen in the hot air, and the oxides thus formed are absorbed by the porous bone ash. The Chaldeans are said to have been the first to have utilized (ca. 2500 b.c.e.) cupellation to remove lead and purify silver from lead-silver ores. [Pg.189]

The overall distribution of lanthanides in bone may be influenced by the reactions between trivalent cations and bone surfaces. Bone surfaces accumulate many poorly utilized or excreted cations present in the circulation. The mechanisms of accumulation in bone may include reactions with bone mineral such as adsorption, ion exchange, and ionic bond formation (Neuman and Neuman, 1958) as well as the formation of complexes with proteins or other organic bone constituents (Taylor, 1972). The uptake of lanthanides and actinides by bone mineral appears to be independent of the ionic radius. Taylor et al. (1971) have shown that the in vitro uptakes on powdered bone ash of 241Am(III) (ionic radius 0.98 A) and of 239Pu(IV) (ionic radius 0.90 A) were 0.97 0.016 and 0.98 0.007, respectively. In vitro experiments by Foreman (1962) suggested that Pu(IV) accumulated on powdered bone or bone ash by adsorption, a relatively nonspecific reaction. On the other hand, reactions with organic bone constituents appear to depend on ionic radius. The complexes of the smaller Pu(IV) ion and any of the organic bone constituents tested thus far were more stable (as determined by gel filtration) than the complexes with Am(III) or Cm(III) (Taylor, 1972). [Pg.41]

The results of experiments conducted by MacKenzie and McCollum (15) indicate that the effect of dietary oxalic acid on the rat depends on the composition of the diet. There was no effect on rate of growth or calcium excretion of 50 g rats fed for 10 weeks a diet containing 0.6% calcium, 0.7% phosphorus, and optimum vitamin D, when levels of potassium oxalate up to 2.5% were fed. The percent bone ash on the 2.5% oxalate diet was somewhat lower than on the control diet. On a 0.35% calcium, 0.35% phosphorus, and vitamin D-free diet, 1.7% potassium oxalate resulted in restricted growth and bone formation of weanling rats. [Pg.107]

The selectivity (or specificity ratio) is useful for defining the magnitude of an analytical interference for real situations. Photon ratios serve only to demonstrate the demands upon the spectrometer. The selectivity ratio is the concentration of interfer-ent that causes a unit concentration error in the analyte. If the selectivity ratio of 2000 (defined as adequate by industry)(41) is used, the apparent lead concentration in the bone ash will be 250 ppm. A calcium/lead selectivity ratio of 5,000,000 is required to achieve an analytical accuracy of 10 per cent for one ppm lead in bone ash. (The authors are aware of a lead analysis for bone ash containing approximately 30 ppm lead that was reported by an ICP laboratory to contain approximately 550 ppm lead.) In this instance the selectivity ratio was only 1 x 103. [Pg.122]

A common source of organic phosphorus is bone meal (approximately 9-14% P) and bone ash (approximately 18%). The bird excrement guano contains about 2-3% P as ammonium and calcium phosphates. Fresh solid dairy cattle manure has approximately 0.13% P (moisture = 81.7%), and solid swine manure has about 0.33% P (moisture = 71.8%), which will be in both organic and mineral forms. [Pg.112]

Petrow HG, Strehlow CD. 1967. Spectrophotometric determination of thorium in bone ash using arsenazo. 3. Anal Chem 39 265-267. [Pg.148]

Synonyms calcium orthophosphate calcium phosphate tricalcium phosphate tertiary calcium phosphate precipitated calcium phosphate bone ash (technical product). [Pg.174]


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