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Thermal activation currents of biocompatible nanocrystalline calcium hydroxyapatite Ca10(PO4)6(OH)2

“…In accordance with [18,19], two types of pro cesses corresponding to peak appearance can be dis tinguished for TST spectra. First, these are the pro cesses due to both adsorption of water and air oxygen by means of the defect structure of the NCHA surface and participation in the thermal activation processes of structured water and water formed as a result of thermal HA decomposition.…”

“…Interpretation of the physical nature of the temper ature dependences of NCHA TST may be obtained by analogy with the interpretation of thermal activation processes in microcrystalline HA studied using ther mally stimulated exoelectron emission (TSEE) [18,19]. In accordance with [18,19], two types of pro cesses corresponding to peak appearance can be dis tinguished for TST spectra.…”

“…For the problem under consideration, participation of the adsorbed and structured molecules of H 2 O and O 2 and also OH -and O -radicals in appearance of the low temperature peak (Fig. 1) is especially probable as related to the results of the physico chemical analysis of the studied object: NCHA with the gross formula of Second, apart from the effect of adsorption on TST, the active role in thermal activation processes is played by phase transitions in the studied objects accompa nied by distortions in the crystal lattice (formation of stresses and cracks under plastic deformation in the course of thermal expansion) [18,19]. The high tem Table 3.…”

“…Thermal activation current spec troscopy opens wide possibilities for determination of the fundamental relationships between the composi tion, structure, and properties, allowing estimating energy processes occurring in the substance and estab lishing their physical nature [2,3].…”

“…were Ca(OH) 2 and H 3 PO 4 (high purity grade) and distilled water. X ray phase analysis (XRD) and determination of crystallographic characteristics and crystal dimen sions was carried out using a DRON 4 automated dif fractometer (CuK α radiation, a graphite monochro mator, the EXPRESS master program).…”