Calcium hydrogen phosphate

Description of Method. Salt substitutes, which are used in place of table salt for individuals on a low-sodium diet, contain KCI. Depending on the brand, fumaric acid, calcium hydrogen phosphate, or potassium tartrate also may be present. Typically, the concentration of sodium in a salt substitute is about 100 ppm. The concentration of sodium is easily determined by flame atomic emission. Because it is difficult to match the matrix of the standards to that of the sample, the analysis is accomplished by the method of standard additions. 

Calcium Pyrophosphates. As is typical of the pyrophosphate salts of multiple-charged or heavy-metal ions, the calcium pyrophosphates are extremely insoluble ia water. Calcium pyrophosphate exists ia three polymorphic modifications, each of which is metastable at room temperature. These are formed progressively upon thermal dehydration of calcium hydrogen phosphate dihydrate as shown below. Conversion temperatures indicated are those obtained from thermal analyses (22,23). The presence of impurities and actual processing conditions can change these values considerably, as is tme of commercial manufacture. 

The weakness of this cement was its tendency to dissolve in water. This was prevented by including rosin (mainly abietic acid) or hydrogenated rosin in the formulation (Brauer, Simon Sangermano, 1962). Rosin and fused quartz or calcium hydrogen phosphate monohydrate were added to... 

LETS A process for making triple superphosphate (a calcium hydrogen phosphate). Developed by the J. R. Simplot Company in 1976. 

Synonyms calcium hydrogen phosphate secondary calcium phosphate bicalcium phosphate... 

Dibasic calcium hydrogen phosphate may be prepared by several methods. It is precipitated by mixing solutions of calcium chloride and disodium hydrogen phospate ... 

Back titration with EDTA is used in the pharmacopoeial assays of aluminium glycinate, aluminium hydroxide, aluminium sulphate, calcium hydrogen phosphate. 

Still another type of porosimetry curve has recently been reported. Figure 11.5 illustrates mercury intrusion into distinct pore sizes in crystals of calcium hydrogen phosphate. The vertical steps on the curve indicate very narrow bands of pore radii between which no pores exist. Therefore, pores do not always exist over a continuum of radii. 

If the same formula is compressed to half of the weight (formula 9 vs. formula 8), the dissolution rate increases (f50=1.78 h for formula 8, /50= 1.15 h for formula 9). There are two ways to reduce this dissolution rate (1) increasing the amount of HPMC by about 100% (formula 10, 50=1.46 h), but, with such an augmentation, the dissolution rate does not increase very much, and compression is more difficult (2) increasing the amount of calcium hydrogen phosphate in the granulate, before addition of HPMC and lubricants (formula 11, /50=1.93 h). 

If the quantity of HPMC is increased by threefold (formula 13), the quantity of calcium hydrogen phosphate must be augmented to obtain a compressible granulate. In this case, dissolution is only slightly reduced (t50=2.50 h, Fig. 8). 

Because of the toxicity of cadmium, its use was abandoned in the 1980 s. Nevertheless, by improving the quality of the raw materials and changing the reaction stoichiometry, it was possible to reproduce the quantum yield of the halophosphates, even without the addition of cadmium [5.373]. The absorption of the exciting UV radiation is strongly dependent on the particle size of halophosphate phosphors and decreases rapidly for particles larger than 3 pm. The particle size is influenced to some extent by the particle size of raw materials (calcium hydrogen phosphate) in the firing mixture. Mechanical separation processes (sieves) are used to free the fired product from undesired coarse and fine particles. 

Type II diabetes Stimulating the release of insulin from the pancreas. ATP-dependent K-channel blocker Calcium hydrogen phosphate, MCC, maize starch, polacrilin, potassium, povidone, glycerol (85%), magnesium stearate, meglumine, poloxamer Novo Nordisk... 

Fuji Chemical Industry Co. 1996. Calcium hydrogen phosphate, a method for preparing it and an excipient utilizing it. U.S. patent no. 5,486,365. 

THE COMPOSITION OF SOLUTIONS SATURATED WITH CALCIUM HYDROGEN PHOSPHATES.3... 

The System Lime and Phosphoric Acid —Solubility of Calcium Phosphates— Conditions of Formation of Basic and Acid Calcium Phosphates—Composition of Solutions Saturated with Calcium Hydrogen Phosphates—Equilibria between Solid Phases and Solutions at Various Temperatures—Changes during Neutralisation—The Acid Phosphates—Manufacture of Superphosphate—Retrogression—Treatment of Special Ores—Phosphoric Acid— Commercial Preparation and Extraction from Rook—The History and Technology of Superphosphate Manufacture—Mixed and Concentrated Phosphorio Fertilisers—Potassium Phosphates—Ammonium Phosphates. 

Phosphors used in the production of fluorescent lamps are of the calcium halophosphate type, prepared by firing together calcium hydrogen phosphate, calcium carbonate and a lesser amount of calcium fluoride. The phosphor (0.25 g) can be dissolved in a small amount of concentrated... 

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