Urea phosphate

Mixed with additives, urea is used in soHd fertilizers of various formulations, eg, urea—ammonium phosphate (UAP), urea—ammonium sulfate (UAS), and urea—phosphate (urea + phosphoric acid). Concentrated solutions of urea and ammonium nitrate (UAN) solutions (80—85 wt%) have a high nitrogen content but low crystallization point, suitable for easy transportation, pipeline distribution, and direct spray appHcation. 

Urea—Phosphate Type. Phosphoric acid imparts flame resistance to ceUulose (16,17), but acid degradation accompanies this process. This degradation can be minimized by iacorporation of urea [57-13-6]. Ph osph oryl a ting agents for ceUulose iaclude ammonium phosphate [7783-28-0] urea—phosphoric acid, phosphoms trichloride [7719-12-2] and oxychloride [10025-87-3] monophenyl phosphate [701-64-4] phosphoms pentoxide [1314-56-3] and the chlorides of partiaUy esterified phosphoric acids (see Cellulose esters, inorganic). 

Chapter 5 Compounds which contain either an ester or an amide link in a single macrocyclic ring. This includes lactones, lactams, carbonates, carbamates, ureas, phosphates, etc. including sulfur, nitrogen and other atoms in the ring. 

Uremia is characterized by retention in the blood of urea, phosphates, proteins, amines and a number of poorly defined low-molecular-weight compounds. Despite acidemia, the pH of brain, muscle and CSF are normal in humans with renal failure. Whereas brain water, K+ and Mg2+ content are normal, Al3+ and Ca2+ concentrations are significantly increased [14]. 

Crystalline polyammonium catena-polyphosphate, (NH4) H2P 03 + 1, has been prepared by heating urea and monoammonium orthophosphate under ammonia vapor for 16 hours,1 by ammoniation of superphosphoric acid,2 by thermal condensation of urea phosphate,3 and by heating various ammonium phosphates in a current of ammonia.4,5 The procedure given below, in which crude ammonium tetrametaphosphate is reorganized and condensed to a long-chain polymer in a stream of ammonia, is straightforward and permits the use of common laboratory equipment and supplies. 

In the fourth type of fire retardants, a chemical bond between the molecules of the fire retardant and cellulose should produce a finish that strongly resists the effects of laundering and weathering. Among such retardants may be cited cellulose-ammonium phosphate, cellulose-urea phosphate, cellulose-titanium complexes cellulose-titanium-antimony finishes... 

The structures of zinc aspartate tri-hydrate, urea phosphate and cycloserine hydrochloride have been determined by 3-dimensional x-ray methods ami refined by IBM 704 least-squares computations The zinc aspartate analysis [14] reveals H positions and H-bonding which leads to a ring structure for the aspartate ion. Urea phosphate shows strong H-bond throughout the structure [15]. Seven H s are available for nine short bonds. Cycloserine hydrochloride [16, 17] shows seven short mtermolecular distances, suggesting 0—H O,... 

Sundera-Rao R. V. G., Turley J. W. Pepinsky R. The crystal structure of urea phosphate. Acta Cryst. 1957 10 435. 

As a result of GC-MS analyses, 103 metabolites were determined, of which 66 were successfully identified and 18 were used to create a diagnostic model. Of these 18 metabolites, 5 (suberic acid, glycine, L-tyrosine, L-threonine, and succinic acid) had significantly higher levels in patients with HCC than in healthy volunteers (p < 0.05). Other metabolites (oxalic acid, xylitol, urea, phosphates, propanoic acid, threonine, pimelic acid, butyric acid, trihydroxypentanoic acid, hypoxanthine, arabinofuranose, dipeptide of hydroxyproline, and tetrahydroxypentanoic acid) showed higher levels in healthy volunteers (p < 0.05). In addition, Wu et al. determined the levels of AFP using an ELISA test in serum from the same patients and healthy volunteers as in the metabolomic study of urine samples. An AFP concentration above 20 ng/mL suggests a positive result and the presence of... 

Flammability. Flammability of cotton fabrics is not a dangerous characteristic, but certain uses require flame resistance. Impregnation of fabrics with certain inorganic salts such as borax-boric acid and ammonium sulfamate and with chlorinated organic compounds has been used. Other methods have been proposed but have not become generally useful. One of these is the urea-phosphate process and another is the Erifon process. 

Gasser, J.K.P., and A, Penny. 1967. The Value of Urea Nitrate and Urea Phosphate as Nitrogen Fertilizers for Grass and Barley, Journal Agricultural Science, 69 139-146. 

MgO Urea, phosphate rock, KCl, kieserite 445 5 7 Poor... 

Ammonium polyphosphate can be obtained by the direct action of ammonia on polyphosphoric acid containing 83% P2O5. If this product is added to water, a fine precipitate of (NH4P03) is obtained. An alternative preparation (used industrially) is to heat orthophosphoric acid with urea which forms urea phosphate which in turn breaks down at a temperature too low to decompose the product. 

Other fertiliser compounds which can satisfactorily provide phosphorus and nitrogen are urea phosphate, CO(NH2)2 H3PO4, ammonium polyphosphate, [(NH4)P03] and phosphazenes such as P3N3(NH2)g (Table 12.4). Red phosphorus is slowly oxidised in damp soil and has been considered as a possible fertiliser [32,33]. 

The availability of nutrient P is >95% from the calcium phosphates, bone meal and urea phosphate, although it is somewhat lower in the other sources quoted. It is believed that the P in condensed phosphates is unavailable to non-ruminant animals. 

Disodium phosphate, Na2HP04, ammonium phosphates or urea phosphate, CO(NH2)2 H3PO4, may also be used as supplements to animal-feeding compositions. 

Associated dimer units form part of the overall H bonding scheme in urea phosphate (13.12). Larger rings are found in some structures (13.13). 

Phosphoserine N-Phosphoarginine Urea phosphate Spermine phosphate Spermidine phosphate Putrescinium phosphate... 

Productive foldamer research requires foldamers with certain backbone characteristics. The backbone must be stable, easily synthesized and have some degree of flexibility. It is also helpful to have a well-characterized conformational profile, known intermolecular interactions (such as H-bonding), and good handling characteristics, such as solubility. As shown in Tables 44.1 and 44.2, a wide variety of bond forming reactions have been used to build foldamers. The most popular, by far, is the amide bond however, other chemistry highlights include ureas, phosphate esters, ethers, aryl ethynylenes, biphenyls, and pyridines. 

Phosphorus oxynitride (PON) is the name for a family of closely related materials that have been around for over 100 years. They are not well known but are thermally very stable and may be considered as future flame retardants and for intumescent formulations since PON is analogous to ammonium polyphosphate. It can be made from inexpensive starting materials such as ammonium phosphate, melamine phosphate or urea phosphate just by prolonged and intensive heating. 

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