Introduction: The volatile component of apatite [Ca5(PO4)3(F,Cl,OH)] makes it a popular choice for studying the abundance and distribution of indigenous lunar volatiles [e.g. 1-5]. The thermodynamic behavior of volatile partitioning into apatite is, however, poorly constrained. Limited experimental studies of apatite/melt partitioning have focused on terrestrial systems [6], chlorine-brine syst...

The hydrothermal syntheses of hydroxyapatite and polymer composite materials were studied. The apatite precursor slurry was prepared by agitating a mixture of CaCO3 and CaHPO4·2H2O, and 3 kinds of polymeric fibers were added. The mixture was treated under hydrothermal conditions at 180 °C for 5 hours. The XRD patterns of the products showed that the products were well-crystallized hydroxyapatit...

Carbonated hydroxyapatite is the mineral found in vertebrate bones and teeth, whereas invertebrates utilize calcium carbonate in their mineralized organs. In particular, stable amorphous calcium carbonate is found in many crustaceans. Here we report on an unusual, crystalline enamel-like apatite layer found in the mandibles of the arthropod Cherax quadricarinatus (freshwater crayfish). Despite ...

A new method for altered enamel surface remineralization has been proposed . To this aim carbonate-hydroxyapatite nanocrystals which mimic for composition, structure, nanodimensions, and morphology dentine apatite crystals and resemble closely natural apatite chemical-physical properties have been used The results underline the differences induced by the use of fluoride ions and hydroxyapatite ...

A series of nanocrystalline calcium hydroxyapatites was prepared by dry milling and characterized using proton and 31P MAS NMR, TEM, and TGA methods. The samples contained stubby rod-shaped crystals, which length and width varied in the 130-30 and 95-20 nm ranges, respectively. It was confirmed that concentration of structural hydroxyl groups in nanocrystalline apatites decreases with the decre...

Supercritical water was used as a modification method of electrochemically deposited apatite on pure titanium. The apatites were coated on a commercially pure titanium plate using a hydrothermal-electrochemical method. A constant direct current at 12.5mA/cm2 was loaded for 1hr at 25, 60, 100, 150 and 200•Ž in an electrolyte containing calcium and phosphate ions. The deposited apatite on the tit...

Enamel, the outermost layer of teeth, is an acellular mineralized tissue that cannot regenerate; the mature tissue is composed of high aspect ratio apatite nanocrystals organized into rods and inter-rod regions. Amelogenin constitutes 90% of the protein matrix in developing enamel and plays a central role in guiding the hierarchical organization of apatite crystals observed in mature enamel. To...

Many proteins in the inorganic/organic matrix of bone induce or modulate or inhibit mineralization of apatite in vivo. Many attempts have been made to mimic and understand this mechanism as part of bone formation, and ectopic mineralization and control thereof. Many attempts have also been made to use such proteins or protein fragments to harness their potential for improved mineralization. Suc...

objective(s): hardystonite (ht) is zn-modified silicate bioceramics with promising results for bone tissue regeneration. however, ht possesses no obvious apatite formation. thus, in this study we incorporated sr and ti into ht to prepare sr-ti-hardystonite (sr-ti-ht) nanocomposite and evaluated its in vitro bioactivity with the purpose of developing a more bioactive bone substitute material. ma...