Phosphates, analysis

Analysis. Excellent reviews of phosphate analysis are available (28). SoHds characterization methods such as x-ray powder diffraction (xrd) and thermal gravimetric analysis (tga) are used for the identification of individual crystalline phosphates, either alone or in mixtures. These techniques, along with elemental analysis and phosphate species deterrnination, are used to identify unknown phosphates and their mixtures. Particle size analysis, surface area, microscopy, and other standard soHds characterizations are useful in relating soHds properties to performance. SoHd-state nmr is used with increasing frequency. 

Persson, K. B. (1997), Soil phosphate analysis A new technique for measurement in the field using a test strip, Archaeometry 39, 441-443. 

Woods, W. I. (1977), The soil phosphate analysis of anthropic soils, Am. Antiquity 42, 248-252. 

Bethell, P. and Mate, I. (1989). The use of soil phosphate analysis in archaeology a critique. In Scientific Analysis in Archaeology, ed. Henderson, J., Monograph 19, Oxford, Oxford University Committee for Archaeology, pp. 1-29. 

Environmental water samples to be analyzed for phosphate are not stored in plastic bottles unless kept frozen, because phosphates can be absorbed onto the walls of plastic bottles. Mercuric chloride, used as a preservative and acid (such as the nitric acid suggested for metals above), should not be used unless total phosphorus is determined. All containers used for water samples to be used for phosphate analysis should be acid rinsed, and commercial detergents containing phosphates should not be used to clean sample containers or laboratory glassware. 

It has been shown8263 that the analysis of iron in uteroferrin is dependent on the presence of phosphate. Analysis of the native enzyme with one tightly bound phosphate gives an incorrect low answer suggesting the presence of only one iron. 

Pesticides can be analyzed on a C18 column, the chlorinated hydrocarbon type (chlordane) at 80% An/water UV, 220 nm, the carbamate type (sevin) at 40% An/water UV, 254 nm, and the organic phospahate (malathion) at 50% An/water with UV, 192 nm or with a CAD. The organic phosphate types are hard to detect at low concentration and various phosphate analysis techniques have been evaluated. LC/MS, where available, is the technique of choice for analyzing all of these pesticides, but especially the organic phosphates, in a general gradient HPLC scheme. 

Phenanthroline (o-phenan-throline), complex cation with nickel(II), 5 193n., 195 1-Phenylbiguanide complexes with eobalt(III), 6 71 Phosphate glasses, 3 88 Phosphates, analysis of mixtures of soluble, 3 91... 

Because of the low phosphate analysis of SSP (20% P2Os), economics favor shipping the rock (32% P2Os) to local plants and producing the superphosphate there. A majority of the producers use the locally produced SSP in formulations for granular NPK fertilizers made in an ammoniation-granulation process. The maximum amount of SSP possible is... 

Organic Phosphorus Compounds, Determination of, by Phosphate Analysis... 

Phosphate Analysis, Determination of Organic Phosphorus Compound by (Lindberg... 

The silicate in the injected reagent cannot react in the sample stream because the oxalic acid added upstream of the injector destroys the excess molybdate. However, the quenching of the silicate reaction before injection of the reagent is not essential. Automatic refractive index matching also works well in the phosphate analysis (Figures 4 and 5). Any phosphate in the injected reductant is reactive in this case. The additional phosphate will only make the peaks proportionately larger. Standards must be analyzed by the same procedure used for the samples. 

Salinity was obtained using the Harvey method (9) and was checked with a hand-held refractometer (9). Sihcate and phosphate analysis were obtained by a Technicon AutoAnalyzer II using standard procedures described in the EPA Methods Manual (10). 

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