Phosphorus content

Phosphorus content No phosphorus compound should be present ... 

Phosphor-gehalt, m. phosphorus content, -geruch, m. phosphorus odor, -geschoss, n. phosphorus bullet, incendiary bullet, -gruppe, /. phosphorus group, -guano, m. phosphatic guano. 

With a phosphorus content of 7.9%, PCP showed FR behavior mainly in oxygenated polymers. This is in agreement with the well-known fact that phosphorus compounds are more effective in oxygenated polymers in bringing out flame retardancy than in other polymers [177]. Thus, Table 10 shows that at 20% loading, PCP... 

The presence of active sulphate-reducing bacteria usually results in graphitic corrosion and this has led to a useful method of diagnosing this cause of corrosion. The leaching out of iron from the graphitic residue which is responsible for the characteristic appearance of this type of corrosion leads to an enriched carbon, silicon and phosphorus content in the residue as compared with the original content of these elements in the cast iron. Sulphur is usually lost to some extent but when active sulphate-reducing bacteria are present, this loss is offset by the accumulation of ferrous sulphide in the residue with a consequent increase in the sulphur content of the residue out... 

One disadvantage of tough pitch coppers is the embrittlement that is liable to occur when they are heated in atmospheres containing hydrogen. For many purposes, therefore, and particularly where fabrication is involved, deoxidised coppers are preferred. The usual deoxidising agent is phosphorus, and specifications require residual phosphorus contents of between... 

Phosphonobutane-l,2,4-tricarboxylic acid (PBTC) is the most expensive of the commonly used phosphonates. However it is excellent at providing calcium carbonate control under highly stressed operating conditions. It is most resistant to the problem of calcium phosphonate precipitation and, from an environmental position, has the lowest phosphorus content of the common phosphonates. The acid material has a MW of 270. PBTC has a sequestration value of 280 mg CaC03/g product at a pH level of 11. It is very stable and can operate under very high pH conditions. However, it may also attack copper. Examples include Bayhibit AM, Mayoquest 2100, Phos -9, and Codex 551. 

PCA 16 is available as Beldene 161/164 (50/35% w/w solids), Acumer 4161 (50%), and Polysperse (50%). These are low-phosphorus content materials that have found application in boiler FW formulations because of excellent sludge conditioning and particulate dispersion properties. The number 16 represents a 16 1 w/w ratio of acrylic acid and sodium hypophosphite, giving PCA 16 a MW range of 3,300 to 3,900. PCA 16 is particularly effective for the control of calcium carbonate and sulfate deposition. It is usually incorporated with other polymers in formulations and is approved for use under U.S. CFR 21, 173.310. 

When there is a limitation of the phosphorus content in detergents of 1%, then addition of phosphonates can act as an alternative solution in combination with other polyvalent ion-binding substances. Especially when magnesium is a cause of water hardness the zeoliths can form precipitations. But phosphonates, like hydroxyethanephosphonic acid (HEDP) and ethylenediaminetetra-methylenephosphonic acid (EDTMP), are able to sequester magnesium ions as well. 

The analysis of phosphates and phosphonates is a considerably complex task due to the great variety of possible molecular structures. Phosphorus-containing anionics are nearly always available as mixtures dependent on the kind of synthesis carried out. For analytical separation the total amount of phosphorus in the molecule has to be ascertained. Thus, the organic and inorganic phosphorus is transformed to orthophosphoric acid by oxidation. The fusion of the substance is performed by the addition of 2 ml of concentrated sulfuric acid to — 100 mg of the substance. The black residue is then oxidized by a mixture of nitric acid and perchloric acid. The resulting orthophosphate can be determined at 8000 K by atom emission spectroscopy. The thermally excited phosphorus atoms emit a characteristic line at a wavelength of 178.23 nm. The extensity of the radiation is used for quantitative determination of the phosphorus content. 

The outlined scheme can also be used to calculate the amount of phosphoric acid triesters. In that case the difference must be formed of the total phosphorus content minus that of free phosphoric acid, phosphoric acid monoester, and phosphoric acid diester. The resulting value is then multiplied with the calculated molecular mass of the triester. 

Mention has already been made of the application of alkoxycyclophos-phazenes, [NP(OR)2] , as flame retardants in rayon. Although the methoxy-derivatives, with their high phosphorus content, were expected to be most efficient in this respect, their water solubility proved a major shortcoming. However, the n-propoxy series, [NP(OPr )2] ( mainly 3—6), were found to impart excellent flame resistance and were well retained by rayon. The cyclophosphazene alkoxides were obtained by the addition of sodium-n-propoxide to the chloride homologues, (NPCl2)n, and were added to the viscose dope before the rayon was spun. The flame resistance imparted by various amino- and thioalkoxy-derivatives was also tested, but found to be inferior to the results obtained with alkoxy-deriva-tives. Several patent applications have resulted from work on this topic. ... 

Many more papers deal with rhizosphere phosphatase activity (63-83) in the presence of a number of different plant species this will partly be due to the simplicity of the enzyme activity assay (85,86) and the generally reported, well-correlated variation trends among organic and inorganic phosphorus content and phosphatase activity. More precisely, closer to the roots, the inorganic P depletion zone in comparison with bulk soil is more pronounced in addition, organic and inorganic P contents are inversely correlated, and the mineralization rate of or-... 

Sulfur and phosphorus content Coals should assay low in these harmful impurities as they have adverse effects on the properties of the metal. Moreover, gases produced from sulfur- and phosphorusbearing coals are corrosive to equipment and pollute the atmosphere. 

Purity It should have moisture, ash, sulfur and phosphorus contents as low as possible. 

The silicon map shows the distribution of slag inclusions, while the position of the weld lines can be seen to be marked by boundaries between areas of high and low phosphorus content and by enrichments of nickel and/or arsenic at the weld lines. Higher resolution maps can be made of welds to reveal their fine structure. 

The rising cost of scrap and waste disposal, the scarcity of onsite landfill space, and potential environmental liabilities make it an economic necessity to recover iron units from dust and sludge. However, recycling to the blast furnace raises the hot metal phosphorus content to undesirable levels. 

Phosphorus accounts for 2 1% of the dry weight of living cells. The phosphorus content of the environment can be the life-conserving or life-limiting factor (Karl, 2000). 

Fig. 16.2 A 3-year on-farm comparison study in Switzerland where microbial activity in orchard soils (expressed as the ratio of microbial bound carbonmitrogen) was higher (low values indicate higher bacterial presence and activity) in organic (filled symbols) than in integrated (open symbols) managed orchards (same symbol shape = orchards in the same village), (a) A clear correlation between the Cmic Nmic ratio to phosphorus content of the fruit flesh was found which (b) in turn was correlated with the fruit quality index (including sugar and acidity content and fruit flesh firmness) P = phosphorus content of the fruit fresh in mg/kg dry matter.

Cymbaluk, N.F. and G.I. Christison. 1989. Effects of dietary energy and phosphorus content on blood chemistry and development of growing horses. Jour. Anim. Sci. 67 951-958. 

Total phosphorus content of phosphate rocks is relatively unimportant, since what really matters is its reactivity in the soil, which in turn depends on the soil itself, the rock mineralogy and the level of rock grinding. 

Total oxidation reactions, in the presence of water, 19 87 Total oxygen demand (TOD) in wastewater treatment, 25 885 Total phosphorus content, determining,... 

A sample of phosphonic acid resin Diaion CRP200 in wet Na+ form was kindly provided from Mitsubishi Chemical Co. Ltd. This wet resin sample was dried in vacuum, and then the resin with particle sizes of 60 - 32 mesh was selected by meshing. The selected resin was conditioned by treatment with 1 M HC1, water, 2 M NaOH, water, 1 M HC1, and water in successive. Finally, thus, the resin was changed into H+ form. The phosphorus content and acid capacity of the selected resin in the H+ form were measured according to the reported methods and were 4.6 mmol/g and 8.8 meq/g, respectively. Wet volume of the resin was 2.6 ml/g. Hereafter, this is abbreviated as CRP200 for simplicity. 

Exchangers Phosphorus content Sulfur content Acid capacity... 

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