Phosphate extractants

Phosphorus (P), 19 1-19. See also GaAsP system Gallium phosphide (GaP) semiconductor InGaAsP alloy Organophosphorus extractants Phosphate fertilizers atomized, 18 820... 

Consequently, very little money has been sunk into extracting phosphate rock in Florida or in increasing nitrogen fertilizer capacities, for a new ammonia and urea unit can cost as much as 250 to 500 million to build in the U.S., depending on the state of the existing infrastructure. 

Trace phosphate determination is effected by extraction with an organic solution of a quaternary ammonium salt, silylation of the extracted phosphate directly in the organic layer and gas-chromatographic measurement with FID or FPD ... 

Onken, A.B., and R.L. Matheson. 1982. Dissolution rate of EDTA-extractable phosphate from soils. Soil Sci. Soc. Am. J. 46 276-279. 

Morei ef a/. (1996) [5] Chioroform iiquid and vapour, 75 min thereafter 40 h equilibration prior to extraction Deionized water, 16 h,1 10 0-50 mg P/kg soil during 24 h equilibration and 16 h extraction Phosphate None... 

Myers ef a/. (1999) [7] Hexanoi liquid, 24 h Fe-coated paper or HCO3-resin strips, 24 h 25 mg P/kg during extraction Phosphate None... 

Haynes, R.J. and Swift, R.S. (1985) Effects of airdrying on the adsorption and desorption of phosphate and levels of extractable phosphate in a group of New Zealand soils. Geoderma 35, 145-157. 

Pardo, P., J. F. L6pez-Sinchez, G. Rauret, V. Ruban, H. Muntau P. Quevauviller, 1999. Study of the stability of extractable phosphate content in a candidate reference material using a modified Williams extraction procedure. Analyst 124 407-41. 

Fig. 8 Colony formation assay of tin-zinc alloy film SS400 [18]. Each extract was added to the supernatant of V79 culture plate (the ratio of extract to supernatant was 2 5). After a 5-day culture, each culture plate was stained with Giemsa dye and we counted the number of colonies formed in each culture condition (n = 3). 1 No extract (phosphate buffer was added in spite of extract) 2 Added extract of zinc-plating SS400 3 Added extract of SnZn layered SS400 (no heat treatment) 4 Added extract of SnZn-250 5 Added extract of SnZn-350 6 Added extract of SnZn-450. and show p < 0.05 v.s. SnZn-350 and p < 0.01 v.s. SnZn-350 of the result of Student s t test respectively...

Twenty per cent TBF dissolved In kerosene was used as extractant. The partition coefficient, increases with Increased TBF concentration. Increases with increased pH, and decreases with increased sulfate concentration. Vanadium and Iron (ill) are appreciably extracted by TBP from thiocyanate solutions. Copper, titanium, cobalt are weakly extracted. Iron (ll), cadmium, molybdenum, magnesium and aluminum are essentially not extracted. Phosphate Ion may cause the precipitation of uranium or complex formation when present in large amounts. Okada, et al. report the extraction of uranium by TBP, mesityl oxide, and methyl ethyl ketone from phosphoric acid solutions having 20 times as much ammonium thiocyanate as uranium. 

Validation of P NMR as a quantitative analytical procedure requires the determination of T, and NOE values of the muscle extract phosphates (Table I). The T, values of Table I can be compared with the data determined on pure aqueous solutions in the case of five of the compounds. The... 

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