A Study on the Thermal Properties of Dibasic Calcium Hydrogen Phosphate and Monobasic Calcium Phosphate.

Abstract The conversion of calcium phosphate into calcium diphosphate through cyanate in an aqueous suspension, discovered by Miller and Parris [1], has been reinvestigated thor-oughly. The reaction is initiated through the disproportionation of calcium hydrogen phosphate to give hydroxylapatite and calcium dihydrogen phosphate, which reacts with cyanate via carbamoylphosphate to yield calcium diphosphate and urea. In particular, it could be shown that the process of phosphate condensation may also be initiated when cyanate is generated by a photochemical oxidation of hydrocyanic acid. -The importance of this reaction with respect to the prebiotic synthesis of biopolymers is discussed.

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Optical and thermal properties of binary calcium phosphate and barium phosphate glasses

Optical Materials ◽

10.1016/j.optmat.2004.12.010 ◽

2006 ◽

Vol 28 (3) ◽

pp. 200-206 ◽

Cited By ~ 37

Author(s):

E.T.Y. Lee ◽

E.R.M. Taylor

Keyword(s):

Thermal Properties ◽

Calcium Phosphate ◽

Phosphate Glasses

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The Influence of Three Additives on the Setting Reaction Kinetics and Mechanical Strength Evolution of [Alpha]-Tricalcium Phosphate Cements

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.493-494.397 ◽

2011 ◽

Vol 493-494 ◽

pp. 397-402

Author(s):

H.A.I. Cardoso ◽

M. Motisuke ◽

Cecília A.C. Zavaglia

Keyword(s):

Calcium Phosphate ◽

Mechanical Strength ◽

Reaction Kinetics ◽

Tricalcium Phosphate ◽

Hydrogen Phosphate ◽

Disodium Hydrogen Phosphate ◽

Setting Reaction ◽

Calcium Phosphate Cements ◽

Strength Evolution ◽

Low Load

Among the calcium phosphate cements, the system based on alpha-tricalcium phosphate (α-TCP) combines several interesting properties. However, these cements have their use limited to low load applications. The main objective of this study is to evaluate the influence of three different additives on the setting reaction kinetics and mechanical strength evolution of calcium phosphate cements as a function of time. The cement was obtained by mixing α-TCP powder with four different aqueous solutions containing or not containing disodium hydrogen phosphate (Na2HPO4), citric acid (C6H8O7) and/or tannic acid (C76H52O46). It was observed that two cement samples, one of them containing Na2HPO4 and C6H8O7 and another containingNa2HPO4 and C76H52O46 in the liquid phase, presented faster setting reaction and higher mechanical properties. These cements are more suitable for application as bone cement.

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Comments on AOAC Dry Ash Method for Digestion of Mineral-Mix Feeds

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/71.4.854 ◽

1988 ◽

Vol 71 (4) ◽

pp. 854-854

Author(s):

George W Latimer ◽

Wayne Ilger ◽

Heron Hinojosa ◽

Marta Roth

Keyword(s):

High Temperature ◽

Calcium Phosphate ◽

Aoac Method ◽

Monobasic Calcium Phosphate

Abstract Phosphorus in feeds or mineral mixes containing monobasic calcium phosphate cannot be determined accurately if the sample is subjected to the dry ash procedure described in AOAC method 7.125-7.128. HCl-insoluble calcium metaphosphates are formed at the high temperature required for ashing.

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