Optical absorption and ESR spectra of reduced vanadium centres in Ca2NaMg2VjOlz are reported. The spectra are interpreted as arising from tetrahedrally coordinated V" and octahedrally coordinated V". The ESR and optical data are correlated using molecular orbital (MO) theory. The composition of the flux-grown single crystals is analysed and discussed.

Observations by transmission electron microscopy show that lamellae of clinoenstatite are present in diopside grains of the Alpe Arami garnet lherzolite of the Swiss Alps. The simplest interpretation of the orientation, crystallography, and microstructures of the lamellae and the phase relationships in this system is that the lamellae originally exsolved as the high-pressure C-centered form of ...

Electrical conductivity of minerals is sensitive to water content and hence can be used to infer the water content in the mantle. However, previous studies to infer the water content in the upper mantle were based on pure olivine model of the upper mantle. Influence of other minerals particularly that of orthopyroxene needs to be included to obtain a better estimate of water content in view of ...

Theoretical simulations of temperature elevations in root dentin are performed to evaluate how heating protocols affect the efficacy of using Er,Cr;YSGG pulsed lasers for bacterial disinfection during root canal treatments. The theoretical models are generated based on microCT scans of extracted human teeth. Heat transfer simulations are performed using the Pennes bioheat equation to determine ...

Ce3+-activated Gd3Al5O12 garnet, effectively stabilized by Lu3+ doping, has been developed for new yellow-emitting phosphors. The powder processing of [(Gd1-x Lu x ) 1-y Ce y ]3Al5O12 solid solutions was achieved through precursor synthesis via carbonate precipitation, followed by annealing. The resultant (Gd,Lu)AG:Ce3+ phosphor particles exhibit typical yellow emission at ∼570 nm (5d-4f transi...

A garnetite that occurs locally in phyllitic schists exposed by the Santorini caldera consists mainly of euhedral garnet crystals showing alternating isotropic and birefringent lamellae. X-ray diffraction revealed two garnets with unit cell dimensions a of I2.o52:ko-oo2 and I~'984-ko-oo5 A, corresponding respectively to almost pure andradite and a granditic phase. Mean compositions determined b...