Phosphate measurement

Table 1 Discharge, nutrient concentrations, and nutrient uptake lengths for ammonium, nitrate, and phosphate measured at reaches located upstream (UP) and downstream (DW) of WWTP effluent inputs in flve European streams... 

On-line phosphate measurement is more often limited to orthophosphates, the total phosphorus measurement needing a mineralization step that is difficult to carry out on site. However, some recent works have been published [27, 28] based on the use of a biosensor or of UV spectrophotometry (after reagent addition). The limit of detection is rather high for this analyte (0.5 mg L 1 or higher). 

Mount ME. 1984. Diagnostic value of urinary dialkyl phosphate measurement in goats exposed to diazinon. Am J Vet Res 45(4) 817-24. 

Sodium citrate solution, at a concentration of 34 to 38 g/L in a ratio of 1 part to 9 parts of blood, is widely used for coagulation studies because the effect is easily reversible by addition of Ca. Because citrate chelates calcium, it is unsuitable as an anticoagulant for specimens for measurement of this element. It also inhibits aminotransferases and alkaline phosphatase but stimulates acid phosphatase when phenylphosphate is used as a substrate. Because citrate complexes molybdate, it decreases the color yield in phosphate measurements that involve molybdate ions and produces low results. 

Stickler et al. (S69) claimed that serum alkaline phosphatase is increased in all patients with vitamin D-resistant rickets and used serum alkaline phosphate measurements to diagnose familial hypophosphatemic rickets in the neonatal period (S16, S68). However, it is generally thought that vitamin D-resistant rickets is not always accompanied by serum alkaline phosphatase elevation (Mc3). 

The result of the phosphate measurement shown in Fignre 6.15 indicates that flux chamber measurements are restricted to a certain number of measurable parameters. Even more, this is true for profiling lander systems. Apart from oxygen, only pH-, pCOj-, H S and Ca-electrodes have been successfully employed on in situ lander systems (Cai et al. 1995 Hales and Emerson 1997 Wenzhofer et al. 2001a de Beer et al. 2005). There is, however, another microelectrode technique... 

Figure 1 Concentrations of cadmium vs. phosphate measured in ocean water samples worldwide. Circles = Paeifie, diamonds = Atlantic, squares = Antaretie, triangles = Indian Ocean. Reprodueed by permission from Ref. [66].

Fig. 22. Intracellular response of glucose-6-phosphate (G6P), AMP, ADP, and ATP in S. cerevisiae in response to a glucose stimulus in continuous culture (D = 0.1 h" ) measured with the aid of the stopped-flow sampling technique. Long-term glucose-6-phosphate measurements from Theobald et al. [65]...

The behavior of fertilizers in relation to crop-spraying aircraft is examined by Marshall and Neubauer (1955), who rate copper or cobalt sulfides (either on their own or in superphosphates) as unsuitable for use with galvanized steel equipment. Ammonium phosphate (measured corrosion rate 250 p,m/year) and nitrolimes (corrosion rate 300 p,m/year) can be used only with care, for short times. Salt (100 p,m/year) is better, as is calcium phosphate, while chalk and bone meal have little effect on galvanized steel. 

Van Veldhoven, P. P., and Mannaerts, G. P. (1987). Inorganic and organic phosphate measurements in the nanomolar range. Anal. Biochem. 161, 45-48. 

The oxidation to form acyl phosphates is reversible. Acyl groups may also be transferred by this enzyme. Acetyl groups are transferred from acetyl phosphate to the sulfhydryl groups of compounds such as glutathione and CoA acetyl phosphate is hydrolyzed in the presence of arsenate and the phosphate of acetyl phosphate is exchanged with inorganic phosphate (measured by labeling with These reactions... 

The reaction is terminated by the addition of trichloroacetic acid and inorganic phosphate measured by the method of Fiske and Subbarow (1925). 

The ground polymer mixed with sodium carbonate is decomposed hy igniting in an oxygen filled flask containing dilute sulfuric acid. The solution is treated with molyhdate-hydrazine reagent and the phosphate measured colorimetrically as its heteropoly-blue equivalent. 

P, mainly in the form of RNA and DNA, polyphosphates and phospholipids, with minor amounts of other P-containing cell biochemicals like adenosine phosphates. Measurement of the P content of the microbial biomass is an essential prerequisite for assessing its role in the P cycle, and its effect on plant nutrition. Until very recently, estimates of microbial P have had to be made from microbial biomass measurements, and literature values for the P contents of laboratory cultured microorganisms which can vary widely depending on growth conditions. ... 

Fig. 4. Comparison of calculated and observed CD spectra of dinucleoside phosphates. Measured ribo ApA agrees well with calculation for a single strand in RNA geometry, while the measured deoxyribo ApA agrees well with a single strand in B-form DNA geometry. (Reprinted from C.L. Cech and 1. Tinoco, Jr. Biopolymers 15 (1976).)...

Using a supporting electrolyte of 10 M in sodium chloride and in ortAo-phosphate, measure the mobility of the particles over a pH range 5.5-10. Comment on the plot mobility/pH in this case, compared to the plot obtained without phosphate. 

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