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A series of sodium cadmium phosphate glasses was prepared in a platinum crucible by melt quench technique. These glasses contain a mole% composition of x%Na₂O-(50-x)%CdO-50%P₂O₅, where the quantity x lies in 0–40 mole%. In this work the physical properties of these glasses were studied, which are reported as mass density ρ, oxygen packing density, molar volume, sodium ion concentration, modulus of rigidity η, coefficient of linear expansion α, transition temperature T_g, and softening temperature T_s. The mass density, oxygen packing density, modulus rigidity, transition temperature and softening temperature show decreasing trend with increasing concentration of sodium ions in these glasses, whereas molar volume and coefficient of linear expansion indicate an increase with increasing concentration of sodium oxide.

The dissolution of xCaO · (90-x)P₂O₅ · 10K₂O glasses (x≤35 mol%) in simulated biological media (decationized water, physiological serum and chlorine acid, pH=1.5), at room temperature, in static regime during 24 h was investigated. The data indicates that the corrosion behavior of the samples depends on the pH of the solutions, glass composition and local structure. In the investigated time range, one observes two leaching stages relative to the incipient dissolution. In the first stage, the lowest release rate is obtained from the potassium-phosphate matrix in decationized water, while for the whole time the lowest leaching rate is recorded again in decationized water but from the sample containing small amount of lime, with CaO/P₂O₅ ratio of 0.06. When the substitution of P₂O₅ by CaO exceeds 50%, the release behavior changes in the investigated media.

Frequency dependence of AC conductivity of four different solid electrolyte materials (covering electronic conduction, mixed conduction and ionic conduction) have been performed and the experimental data were analyzed according to a power law, which were frequently referred to as the so-called universal dynamic response (UDR). Results indicated for the four different materials, the power law exponent first decreases with increasing temperature. At a certain temperature, it exhibits a minimum and then increases again. For this novel phenomenon, the preliminary theoretical explanations and predictions also have been presented.

Phosphate glasses doped with Dy${}^{3+}$ ions and containing silver nanoparticles (SNPs) were synthesized in the present work. We report photoluminescence characterization by absorption and emission spectra. The effect of Ag concentration on the thermoluminescence (TL) glow curves was studied. The scanning electron microscopy (SEM) shows the formation of SNP. Absorption spectra of the samples show the influence of the SNP in the bands 350nm at 425nm associated with the Dy${}^{3+}$, in the same spectra we can see the bands 750, 800, 875, 1098, 1278nm and 1675nm belonging to the Dy${}^{3+}$. Emission spectra show two prominent bands at 480nm and 574nm and one faint band at 665nm corresponding to ⁴F${}_{9∕2}{\to }^6$H${}_{15∕2}$, ⁴F${}_{9∕2}{\to }^6$H${}_{13∕2}$ and ⁴F${}_{9∕2}{\to }^6$H${}_{11∕2}$ transitions, respectively. All bands under 364nm pumping, and the fluorescence in the 550nm and 590nm spectral range enhanced four times. The Commission Internationale de 1’Eclairage (CIE) color coordinates were evaluated from the emission spectra to simulate white light emission from the phosphate glasses. The photostability of the samples was also studied in the UVA (315–403nm) and UVB (280–315nm) ranges. TL due to ultraviolet radiation (UVR) was studied; the glow curves show significant dependence of the TL intensity with the increment of SNPs in the samples. These results show the phosphate glasses doped with Dy${}^{3+}$ and containing SNP as a potential candidate have to be used in solid-state illumination and retrospective dosimetry.

Phosphate glasses are of a great interest for bone substitution materials, due to their chemistry close to that of the inorganic phase of bone and their unique property of being completely soluble. The aim of this study is to evaluate the kinetics of dissolution and the evolution of the mechanical properties of a phosphate glass in the system P₂O₅-CaO-Na₂O when kept in simulated body fluid (SBF). The results showed that the dissolution presented two different stages. In the first stage, the glass showed a mass loss varying at a rate proportional to t^0.55 and, after a certain time, the kinetics turn to linear dissolution. The mechanical properties during the dissolution of the glass showed values of E between 48 and 57 GPa and σ_f between 130 and 167 MPa. The glass showed no significant decrease of its mechanical properties after 8 weeks in SBF. The properties obtained are really promising for the use of phosphate glasses as a bone substitute in certain surgical applications.