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Polyphosphates organic

These can be classified as nutrients (basically nitrogen- and phosphorus-containing species such as nitrate, nitrite, orthophosphate, polyphosphate, organic phosphate), toxic species (cyanide), and others (sulfide, sulfate, sulfite). [Pg.5056]

Conductivity Suspended Solids Orthophosphate Polyphosphate Organic Phosphate Total Organic Carbon Ceilcium, Total Calcium, Dissolved Magnesium, Total Magnesium, Dissolved Aluminum, Total Aluminum, Dissolved... [Pg.831]

Phosphorus Forms char Red phosphorus, ammonium polyphosphate, organic phosphorus compounds Red phosphorus is difficult to process and toxic. Organic phosphorus compounds are a common alternative, but generally more costly and can lower Tg. [Pg.149]

Synthetic organic chelates and natural organic complexes are sometimes more effective agronomically per unit of micronuttient than inorganic forms, but the organic materials are more expensive. The chelates can be used with both orthophosphate and polyphosphate Hquids and suspensions. [Pg.243]

The decomposition of dithionite in aqueous solution is accelerated by thiosulfate, polysulfide, and acids. The addition of mineral acid to a dithionite solution produces first a red color which turns yellow on standing subsequentiy, sulfur precipitates and evolution of sulfur dioxide takes place (346). Sodium dithionite is stabilized by sodium polyphosphate, sodium carbonate, and sodium salts of organic acids (347). [Pg.150]

Some water samples contain phosphoms forms other than phosphate, eg, polyphosphate, hexametaphosphate, and organic phosphates. These forms can be hydrolyzed to phosphate in hot sulfuric acid solution and deterrnined by the preceding method. The more refractory organic phosphates require digestion in a sulfuric acid—ammonium persulfate solution. Ion chromatography can also be used to measure at 2 to 10 ppb (21). [Pg.231]

Certain vertebrates have an astonishing ability to accumulate vanadium in their blood. For example, the ascidian seaworm Phallusia mammilata has a blood concentration of V up to 1900 ppm, which represents more than a millionfold concentration with respect to the sea-water in which it lives. The related organism Ascidia nigra has an even more spectacular accumulation with concentrations up to 1.45% V (i.e. 14 500 ppm) in its blood cells, which also contain considerable concentrations of sulfuric acid (pH 0). One possibility that has been mooted is that the ascidia accumulates vanadate and polyvanadate ions in mistake for phosphate and polyphosphates (p. 528). [Pg.999]

Quebracho-treated freshwater muds were used in drilling at shallow depths. The name of red mud comes from the deep red color imparted to the mud by quebracho. Muds treated with a mixture of lignite and quebracho, or a mixture of alkaline organic polyphosphate chemicals (alkaline-tannate treated muds), are also included in the quebracho treated muds. The quebracho thinners are very effective at low concentrations, and offer good viscosity and filtration control. The pH of red" muds should be 8.5 to 10 mud temperature should be lower than 230°F. [Pg.667]

Evaporators require the continuous low level (1-3 ppm) application of a suitable antisealant chemical treatment. Traditionally, polyphosphate has been used (sometimes in conjunction with an antifoam and/or a dispersant agent), but it generally performs poorly because of a lack of thermal stability. Treatments based on polymaleic acid (PMA) and other modem organic polymers tend to perform much better. [Pg.56]

Phosphonates are organic phosphates characterized by a C-P-O bond, which is much more resistant to hydrolysis than the polyphosphate bond (O-P-O) or the phosphate ester bond (C-O-P), making them suitable for many types of BW treatment formulation. Phosphonates were originally developed for the industrial and institutional (I I) cleaning market in the 1960s, but are commonly employed in a myriad of applications. [Pg.448]

Lipase is an enzyme which catalyzes the hydrolysis of fatty acid esters normally in an aqueous environment in living systems. However, hpases are sometimes stable in organic solvents and can be used as catalyst for esterifications and transesterifications. By utihzing such catalytic specificities of lipase, functional aliphatic polyesters have been synthesized by various polymerization modes. Typical reaction types of hpase-catalyzed polymerization leading to polyesters are summarized in Scheme 1. Lipase-catalyzed polymerizations also produced polycarbonates and polyphosphates. [Pg.207]

A similar process allows reacting triethyl phosphate and phosphorous pentoxide to form a polyphosphate in an organic solvent [871]. An excess of 1.3 moles of triethyl phosphate with respect to phosphorous pentoxide is the most preferred ratio. In the second stage, a mixture of higher aliphatic alcohols from hexanol to decanol is added in an amount of 3 moles per 1 mole phosphorous pentoxide. Aluminum sulfate is used as a crosslinker. Hexanol results in a high-temperature viscosity of the gel, while maintaining at a pumpable viscosity at ambient temperatures [870]. [Pg.110]

A gel of diesel or crude oil can be produced using a phosphate diester or an aluminum compound with phosphate diester [740]. The metal phosphate diester may be prepared by reacting a triester with phosphorous pentoxide to produce a polyphosphate, which is then reacted with an alcohol (usually hexanol) to produce a phosphate diester [870]. The latter diester is then added to the organic liquid along with a nonaqueous source of aluminum, such as aluminum isopropoxide (aluminum-triisopropylate) in diesel oil, to produce the metal phosphate diester. The conditions in the previous reaction steps are controlled to provide a gel with good viscosity versus temperature and time characteristics. All the reagents are substantially free of water and will not affect the pH. [Pg.265]

In this paper, results on the ECH of representative substrates are presented i) in order to illustrate the advantages and the limitations of the ECH at Raney metal electrodes as a method of hydrogenation of organic compounds and ii) in order to discuss some synthetic and mechanistic aspects. The Raney metal electrodes consisted of Raney metal particles embedded in a nickel matrix (1) or dispersed in a lanthanum polyphosphate matrix (2), or of pressed Raney metal alloy of which the outmost layer only has been leached (3). [Pg.4]

Tohgi H, Sasaki K, Chiba K and Nozaki Y (1990). Effect of vinpocetine on oxygen release of hemoglobin and erythrocyte organic polyphosphate concentrations in patients with vascular dementia of the Binswanger type. Arzneimittelforschung, 40, 640-643. [Pg.285]

Panswad T, Iamsamer K, Anotai J (2001) Decolorization of azo reactive dye by polyphosphate and glycogen accumulating organisms in an anaerobic aerobic sequencing batch reactor. Bioresour Technol 76 151-159... [Pg.34]

Mnkeni PNS, MacKenzie AF (1985) Retention of ortho- and polyphosphates in some Quebec soils as affected by added organic residues and calcium carbonate. Can J Soil Sci 65 575-585 Ogaard AF (1996) Effect of fresh and composted cattle manure on phosphorus retention in soil. [Pg.345]


See other pages where Polyphosphates organic is mentioned: [Pg.835]    [Pg.837]    [Pg.834]    [Pg.836]    [Pg.835]    [Pg.837]    [Pg.834]    [Pg.836]    [Pg.239]    [Pg.476]    [Pg.180]    [Pg.300]    [Pg.382]    [Pg.152]    [Pg.152]    [Pg.418]    [Pg.788]    [Pg.792]    [Pg.797]    [Pg.46]    [Pg.401]    [Pg.1530]    [Pg.127]    [Pg.128]    [Pg.105]    [Pg.110]    [Pg.291]    [Pg.475]    [Pg.91]    [Pg.371]    [Pg.107]    [Pg.140]    [Pg.563]    [Pg.645]    [Pg.51]    [Pg.6]   
See also in sourсe #XX -- [ Pg.256 ]




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Polyphosphates

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