The effect of dentifrices and toothbrushing on the wear of enamel, exposed dentin, and cementum has been the topic of extensive experimental research.1-3 Little attempt has been made, however, to study the mechanisms that control the surface failure of enamel under an applied stress that results primarily from sliding. To identify the wear phenomenon of enamel at the level of slip or cleavage i...

The article presents the results of first study stage aimed at analyzing luminescent properties main and minor minerals composing apatite–nepheline ores host rocks in deposits Khibiny rock massif (Kola Peninsula, Russia). purpose work was a search stable identification feature providing fast safe determination fluorapatite mineral mixture solving technological tasks, namely sampling borehole wa...

the dalir phosphate horizon is located ~57 km southwest of chalous, mazandaran province. the horizon developed as stratiform within upper shale of soltanieh formation (late neoproterozoic - early cambrian). according to mineralogical data, the major minerals of the phosphate horizon are calcite, fluorapatite, dolomite, quartz, pyrite, muscovite, and illite. microscopic evidence such as existenc...

In the reverse anionic flotation of phosphate ores using phosphoric acid, it is often suggested that a selective surface passivation minerals by calcium occurs. Several species have been proposed in literature for this passivation. study, in-situ Raman spectroscopy was used to monitor as function time interaction acid with calcite and fluorapatite at fixed pH 4.5 or concentrations order identif...