In this paper we re-examine the alkali dependence of the fraction of four-coordinated borons (N4) in two series of glasses: alkali borates (0·4M2O.B2O3) and mixed lithium caesium borates (0·4(xLi2O+(1-x)Cs2O). B2O3). High field B MAS-NMR experiments were performed to maximise the accuracy of the present results. We found no evidence for an alkali dependence on N4 in either system. In each case ...

Bioactive glass (BG) and glass-ceramics (GC) have been employed for bone treatment tissue engineering applications. glasses/bioglasses can be considered promising materials bone-regenerative scaffolds fabrication, owing to the adaptable properties that make them appropriately designed regarding their composition. The essential of bioactive glasses, enabling applied in tissue, explained as poten...

The objective of this work is to investigate the effect of alkali content and temperature on the microstructure of lithium borate glasses, xLi2O · (1 − x)B2O3. We have applied the molecular dynamics technique with Ewald summation and periodic boundary conditions to a collection of ca. 256 particles confined within a primitive cubic cell and interacting through a BornMayer-Huggins type of potent...

Since the discovery of fast ionic conductivity in glasses, there has been a large interest in explaining the diffusion mechanism. With this knowledge one may be able to design new glasses with optimized properties for various applications. It is well known that the ionic conductivity increases rapidly when a network glassformer is modified by the addition of a metal alkali. Despite considerable...

The dependence of the glass transition temperature on silicate composition as well as on borate composition is discussed. Some new experimental results on borosilicate glass-enamels are put together with the existing literature data. It is demonstrated that in the glass transition interval the activation energy E(Tg) for viscous flow is related to the glass transition temperature. The activatio...

The mixed glass former effect (MGFE) is defined as a nonlinear and nonadditive change in the ionic conductivity with changing glass former fraction at constant modifier composition between two binary glass forming compositions. In this study, mixed glass former (MGF) sodium borophosphate glasses, 0.35Na2O + 0.65[xB2O3 + (1 – x)P2O5], 0 ≤ x ≤ 1, have been prepared, and their sodium ionic conduct...

Zinc borate binary glasses of composition 4Zn0.3B,03 undoped and doped with 0.5% mol of Eu3' were prepared from the melt giving rise to samples of excellent optical quality. In the present work we use the spectroscopic properties of the Eu3' to obtain information about the structural and dynamic features of our system. Different optical techniques such as site selection, excitation spectroscopy...

We developed new optic devices - singly-doped luminescence glasses and nanoparticle-coated lenses that convert UV light to visible light - for improvement of visual system functions. Tb(3+) or Eu(3+) singly-doped borate glasses or CdS-quantum dot (CdS-QD) coated lenses efficiently convert UV light to 542 nm or 613 nm wavelength narrow-band green or red light, or wide-spectrum white light, and t...