Phosphates in nature

Solubilities and stabilities of calcium phosphates in natural waters have been described (735), as have the nucleation and growth of calcium phosphate from solution (736). Several species have long been known to inhibit the precipitation of calcium phosphates, for example carbohydrates (646) and statherin, the tyrosine-rich peptide which occurs in saliva (737). The role of... 

J. P., A modified single solution method for the determination of phosphate in natural waters , pp. 31-6, copyright 1962, with permission from Elsevier. 

Zhang, J. Z. and Chi, J. (2002). Automated analysis of nanomolar concentrations of phosphate in natural waters with liquid waveguide. Environmental Science and Technology 36 1048-1053. 

Evidence of metal phosphates in natural and anthropogenically contaminated... 

Although the anomeric configuration of the glycosyl phosphate in natural lipid A had not been elucidated at that time, it was assumed to be a and we employed a sufficient long reaction time for this phosphorylation to secure formation of a-phosphates in the following synthesis. Meanwhile the natural glycosyl configuration was established to be a (6) and our choice is fortunately correct. 

McCain, S. Davies, M.S. (1984). Effects of pretreatment with phosphate in natural populations of Agrostis capillaris. New Phytologist 96, 589-99. 

Froelich, P.N. (1988) Kinetic control of dissolved phosphate in natural rivers and estuaries a primer on the phosphate buffer mechanism. Limnol. Oceanogr. 33, 649-668. 

Colman A. S., Karl D. M., Fogel M. L., and Blake R. E. (2000) A new technique for the measurement of phosphate oxygen isotopes of dissolved inorganic phosphate in natural waters. EOS, Trans., AGU, F176. 

Pomeroy L. R. (1960) Residence time of dissolved phosphate in natural waters. Science 131, 1731-1732. 

Fig. 3.1.1. Transitional paths of phosphates in nature. Dashed lines indicate paths instituted by man.

Johnson, D. L., 1971, Simultaneous determination of arsenate and phosphate in natural waters Environmental Science Technology, v. 5, p. 411-414. 

The methods involving basic dyes have been used for determining phosphate in natural waters [38,39,41,43,48,55,59,142], biological materials [47,50,52], soils [45,51], uranium [37], iron [46,49], and nickel, cobalt, copper, and zinc [46]. The FIA technique has also been applied [40,43,48]. 

On-line monitoring of phosphate in natural water and effluent stream by the molybdenum blue method using sequential injection analysis has been described [1]. The detection limit of 0.5 mg r P04 was reported. 

The fluorimetric determination of silicate and phosphate in natural waters based on the different rates of formation of their molybdate heteropolyacids [51]. 

R.N. Fernandes, B.F. Reis, Flow system exploiting multicommutation to increase sample residence time for improved sensitivity. Simultaneous determination of ammonium and ortho-phosphate in natural water, Talanta 58 (2002) 729. 

An alternative interference removal step was developed by Ledo de Medina et al. who developed an IC method for phosphate in natural waters in the presence of high concentration of sulphates. This interference was avoided by first precipitating sulphate as lead sulphate prior to 1C analysis. Samples with high iron content were investigated by Simon. Interferences caused by the precipitation of iron hydroxides from air oxidation of ferrous iron in anoxic water samples and from the alkaline eluent used in IC, were found to affect the determination of phosphate and other inorganic anions in riverine sediment interstitial water samples with high concentrations of dissolved iron (0.5 to 2.0 mmol/1). To eliminate this interference the complexation of iron with cyanide was used prior to IC analysis. ... 

For determination of low concentrations of phosphate in natural waters, the selective preconcentration of phosphate may be required. An example of this was recently shown by Yuchi et al. who used a chelating column loaded with Zr for this purpose (TSK gel AF-chelate Toyopearl 650, 40-90 /rm, containing 30 /rmol/g iminodiacetic acid group). ... 

Byrappa K (1983) The possible reasons for absence of condertsed phosphates in Nature. Bhys Chem Minerals 10 94-95... 

France-Lanord C, Derry LA (1994) 5 C of organic carbon in the Bengal fan Source evolution and transport of C3 and C4 plant carbon to marine sediments. Geochim Cosmochim Acta 58 4809-4814 Froelich PN (1988) Kinetic controls of dissolved phosphate in natural rivers and estuaries A primer on the phosphate buffer mechanism. Littmol Oceanogr 33 649-668 Froelich PN, Bender ML, Heath GR (1977) Phosphoras accumulation rates in metalliferous sediments on the East Pacific Rise. Earth Planet Sci Lett 34 351-359 Froelich PN, Bender ML, Luedtke NA, Heath GR, DeVries T (1982) The marine phosphoras cycle. Am J Sci 282 474-511... 

L.J. Gimbert, P.M. Haygarth, P.J. Worsfold, Determination of nanomolar concentrations of phosphate in natural waters using flow injection with a long path length liquid waveguide capillary cell and soUd-state spectrophotometric detection, Talanta 71 (2007) 1624-1628. 

J.F. van Staden, R.E. Taljaard, Online monitoring of phosphate in natural water and effluent streams using sequential injection analysis, Microchim. Acta 128 (1998) 223-228. 

Fusheng, W., Zhongxiang, W., and Enjiang, T., The determination of trace amounts of phosphate in natural water by flow injection fluorimetry. Analytical Letters 22, 3081,1989. 

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