CALCULATION AND ANALYSIS OF EFFECTIVE ATOMIC NUMBER USING AUTO ZEFFECTIVE METHOD FOR BORO-SILICATE GLASS SERIES GLASS [Li O – B O – SiO 2 2 3 2 – XO] WITH THIRD (5D) D-BLOCK (HF–HG) TRANSITION METALS ELEMENTS (X)

The impact of the doping of the transition metals with Lithium Oxide provides signicant data in Boro-silicate materials. Hence their comprehensive study with Lithium in Boro-silicate glass studied in the present paper. Z-effective shows non consistence in study respective to energy and even more anomalous with respective to the atomic number at lowest energy levels (0.01 MeV). Variations in Z-effective are high with increase in energy among all 5d metals used in given series of glass. For 1 to 100 MeV a small variation observed in data as it ranges 9 to 21 (Zeffective). Even variation is symmetrical within the 5d transition metals except for Hf (72) and Ta (73)

Bioactive Borate-Based Glass Coatings For Titanium Alloy Femoral Stems

Hydroxyapatite (HA)-coated Ti6Al4V stems are currently used in total hip replacement (THR) surgeries. However, the residual stress in the HA coating due to mismatch in coefficient of thermal expansion (CTE) between HA and Ti6Al4V limits their application. Borate-based glasses can be promising alternatives to HA because of their similar CTEs to that of Ti6Al4V and excellent bioactivity that can promote bone repair. In this project, six borate-based glasses (Ly-B0, Ly-B1, Ly-B2, Ly-B3, Ly-B4, Ly-B5) from the B2O3-P2O5-CaO-Na2O-TiO2-SrO series were formulated by increasing the concentration of strontium oxide (SrO)from 0 to 25 in mol% at the expense of B2O3 in the glass series. Increased SrO content induced larger amounts of non-bridging oxygens and resulted in gradual increases in glass transition temperature (Tg). Discs of each glass powder were immersed in de-ionized water under 1, 7 and 30 days, and then the water extracts were used to determine the solubility and osteo-stimulatory effect of the glasses. Sr2+ doping retarded the dissolution rate of the glasses and the higher levels of Sr2+ doping (20 mol% and 25 mol%) promoted proliferation of osteoblasts. Except for Ly-B5 (containing 25 mol% SrO), discs of each glass powder exhibited bacteriostatic behavior against Staphylococcus aureus after 24 hours exposure. The glasses were enamelled onto Ti6Al4V substrates, and then bi-layer double cantilever beam (DCB) specimens were manufactured to measure the Mode I (GIC) and Mode II (GIIC) energy release rate of the glass coating/Ti6Al4V constructs. The mean GIC values increased from 6.56 ± 0.9 to 14.6 1 ± 2.1 J/m2 with increasing SrO content from Ly-B0 to Ly-B5, and the mean GIIC values increased from 36.07 ± 3.8 to 46.92 ± 3.3 J/m2 with increasing SrO content from Ly-B0 to Ly-B5, indicating that the incorporation of 15-25 mol% SrO significantly increased the fracture toughness of the construct. Moreover, the GIC and GIIC values of the coating/substrate system for all the six glasses significantly reduced (p ≤ 0.05) due to degradation in de-ionized water.

Incorporating Germanium Oxide into the Glass Phase of Novel Zinc/Magnesium-Based GPCs Designed for Bone Void Filling: Evaluating Their Physical and Mechanical Properties

The structural role of Germanium (Ge), when substituting for Zinc (Zn) up to 8 mol % in the 0.48SiO2–0.12CaO–0.36ZnO–0.04MgO glass series, was investigated with respect to both the glass chemistry and also the properties of glass polyalkenoate cements (GPCs) manufactured from them. The Network connectivity (NC) of the glass was calculated to increase from 1.83 to 2.42 with the addition of GeO2 (0–8 mol %). Differential thermal analysis (DTA) results confirmed an increase in the glass transition temperature (Tg) of the glass series with GeO2 content. X-ray photoelectron spectroscopy (XPS) showed an increase in the ratio of bridging oxygens (BO) to non-bridging oxygens (NBO) with the addition of GeO2, supporting the NC and DTA results. 29Si magic angle spinning nuclear magnetic resonance spectroscopy (29Si MAS-NMR) determined a chemical shift from −80.3 to −83.7 ppm as the GeO2 concentration increased. These ionomeric glasses were subsequently used as the basic components in a series of GPCs by mixing them with aqueous polyacrylic acid (PAA). The handling properties of the GPCs resulting were evaluated with respect to the increasing concentration of GeO2 in the glass phase. It was found that the working times of these GPCs increased from 3 to 15 min, while their setting times increased from 4 to 18 min, facilitating the injectability of the Zn/Mg-GPCs through a 16-gauge needle. These Ge-Zn/Mg-GPCs were found to be injectable up to 96% within 12 min. Zn/Mg-GPCs containing GeO2 show promise as injectable cements for use in bone void filling.

Bioactive Borate-Based Glass Coatings For Titanium Alloy Femoral Stems

Hydroxyapatite (HA)-coated Ti6Al4V stems are currently used in total hip replacement (THR) surgeries. However, the residual stress in the HA coating due to mismatch in coefficient of thermal expansion (CTE) between HA and Ti6Al4V limits their application. Borate-based glasses can be promising alternatives to HA because of their similar CTEs to that of Ti6Al4V and excellent bioactivity that can promote bone repair. In this project, six borate-based glasses (Ly-B0, Ly-B1, Ly-B2, Ly-B3, Ly-B4, Ly-B5) from the B2O3-P2O5-CaO-Na2O-TiO2-SrO series were formulated by increasing the concentration of strontium oxide (SrO)from 0 to 25 in mol% at the expense of B2O3 in the glass series. Increased SrO content induced larger amounts of non-bridging oxygens and resulted in gradual increases in glass transition temperature (Tg). Discs of each glass powder were immersed in de-ionized water under 1, 7 and 30 days, and then the water extracts were used to determine the solubility and osteo-stimulatory effect of the glasses. Sr2+ doping retarded the dissolution rate of the glasses and the higher levels of Sr2+ doping (20 mol% and 25 mol%) promoted proliferation of osteoblasts. Except for Ly-B5 (containing 25 mol% SrO), discs of each glass powder exhibited bacteriostatic behavior against Staphylococcus aureus after 24 hours exposure. The glasses were enamelled onto Ti6Al4V substrates, and then bi-layer double cantilever beam (DCB) specimens were manufactured to measure the Mode I (GIC) and Mode II (GIIC) energy release rate of the glass coating/Ti6Al4V constructs. The mean GIC values increased from 6.56 ± 0.9 to 14.6 1 ± 2.1 J/m2 with increasing SrO content from Ly-B0 to Ly-B5, and the mean GIIC values increased from 36.07 ± 3.8 to 46.92 ± 3.3 J/m2 with increasing SrO content from Ly-B0 to Ly-B5, indicating that the incorporation of 15-25 mol% SrO significantly increased the fracture toughness of the construct. Moreover, the GIC and GIIC values of the coating/substrate system for all the six glasses significantly reduced (p ≤ 0.05) due to degradation in de-ionized water.

Incorporating Germanium Oxide into the Glass Phase of Novel Zinc/Magnesium-Based GPCs Designed for Bone Void Filling: Evaluating Their Physical and Mechanical Properties

The structural role of Germanium (Ge), when substituting for Zinc (Zn) up to 8 mol % in the 0.48SiO2–0.12CaO–0.36ZnO–0.04MgO glass series, was investigated with respect to both the glass chemistry and also the properties of glass polyalkenoate cements (GPCs) manufactured from them. The Network connectivity (NC) of the glass was calculated to increase from 1.83 to 2.42 with the addition of GeO2 (0–8 mol %). Differential thermal analysis (DTA) results confirmed an increase in the glass transition temperature (Tg) of the glass series with GeO2 content. X-ray photoelectron spectroscopy (XPS) showed an increase in the ratio of bridging oxygens (BO) to non-bridging oxygens (NBO) with the addition of GeO2, supporting the NC and DTA results. 29Si magic angle spinning nuclear magnetic resonance spectroscopy (29Si MAS-NMR) determined a chemical shift from −80.3 to −83.7 ppm as the GeO2 concentration increased. These ionomeric glasses were subsequently used as the basic components in a series of GPCs by mixing them with aqueous polyacrylic acid (PAA). The handling properties of the GPCs resulting were evaluated with respect to the increasing concentration of GeO2 in the glass phase. It was found that the working times of these GPCs increased from 3 to 15 min, while their setting times increased from 4 to 18 min, facilitating the injectability of the Zn/Mg-GPCs through a 16-gauge needle. These Ge-Zn/Mg-GPCs were found to be injectable up to 96% within 12 min. Zn/Mg-GPCs containing GeO2 show promise as injectable cements for use in bone void filling.

Structures and Dissolution Behaviors of Quaternary CaO-SrO-P2O5-TiO2 Glasses

Calcium phosphate glasses have a high potential for use as biomaterials because their composition is similar to that of the mineral phase of bone. Phosphate glasses can dissolve completely in aqueous solution and can contain various elements owing to their acidity. Thus, the glass can be a candidate for therapeutic ion carriers. Recently, we focused on the effect of strontium ions for bone formation, which exhibited dual effects of stimulating bone formation and inhibiting bone resorption. However, large amounts of strontium ions may induce a cytotoxic effect, and there is a need to control their releasing amount. This work reports fundamental data for designing quaternary CaO-SrO-P2O5-TiO2 glasses with pyro- and meta-phosphate compositions to control strontium ion-releasing behavior. The glasses were prepared by substituting CaO by SrO using the melt-quenching method. The SrO/CaO mixed composition exhibited a mixed cation effect on the glassification degree and ion-releasing behavior, which showed non-linear properties with mixed cation compositions of the glasses. Sr2+ ions have smaller field strength than Ca2+ ions, and the glass network structure may be weakened by the substitution of CaO by SrO. However, glassification degree and chemical durability of pyro- and meta-phosphate glasses increased with substituted all CaO by SrO. This is because titanium groups in the glasses are closely related to their glass network structure by SrO substitution. The P-O-Ti bonds in pyrophosphate glass series and TiO4 tetrahedra in metaphosphate glass series increased with substitution by SrO. The titanium groups in the glasses were crosslink and/or coordinate phosphate groups to improve glassification degree and chemical durability. Sr2+ ion releasing amount of pyrophosphate glasses with >83% SrO substitution was larger than 0.1 mM at day seven, an amount that reported enhanced bone formation by stimulation of osteogenic markers.

Comprehensive Comparison on Optical Properties of Samarium Oxide (Micro/nano) Particles Doped Tellurite Glass for Optoelectronics Applications

Rare-earth oxides microparticles doped tellurite-based glass have been studied extensively to improve the capability of optoelectronic devices. We report a detailed comparison between two sets of glass series containing samarium microparticles and nanoparticles denoted as ZBTSm-MPs and ZBTSm-NPs respectively. The two sets of glass have been successfully fabricated via melt-quenching technique with chemical formula {[(TeO2)0.70 (B2O3)0.30]0.7 (ZnO)0.3}1-y (Sm2O3 (MPs/NPs)) y with y = 0.005, 0.01, 0.02, 0.03, 0.04 and 0.05 mol fraction. The TEM analysis confirmed the existence and formation of nanoparticles in ZBTSm-NPs glasses. The density of ZBTSm-NPs glasses was found higher than ZBTSm-MPs glasses due to the distributions of nano-scale particles in tellurite glass network. There was a linear trend of increment in the refractive index in both sets of glass series along with the concentrations of dopants. The refractive index of ZBTSm-NPs glasses was found higher than ZBTSm-MPs glasses due to the shift in compactness of glass structure with nano-scale particles. In comparison, the absorption peaks of ZBTSm-MPs glasses were greater than ZBTSm-NPs glasses which were mainly due to the restriction of electrons mobility in glass network with nano-scale particles. The optical band gap energy in ZBTSm-NPs glasses was found greater than ZBTSm-MPs glasses which correspond to the widening of forbidden gap with nano-scale particles. The polarizability of ZBTSm-NPs and ZBTSm-MPs was found in non-linear trend along with dopant concentrations. Based on these findings, the improvement of optical properties have been made by introducing samarium oxide nanoparticles in tellurite glass which is beneficial for optoelectronic devices.

Incorporating Germanium Oxide into the Glass Phase of Novel Zinc/Magnesium-Based GPCs Designed for Bone Void Filling: Evaluating Their Physical and Mechanical Properties

The structural role of Germanium (Ge), when substituting for Zinc (Zn) up to 8 mol % in the 0.48SiO2–0.12CaO–0.36ZnO–0.04MgO glass series, was investigated with respect to both the glass chemistry and also the properties of glass polyalkenoate cements (GPCs) manufactured from them. The Network connectivity (NC) of the glass was calculated to increase from 1.83 to 2.42 with the addition of GeO2 (0–8 mol %). Differential thermal analysis (DTA) results confirmed an increase in the glass transition temperature (Tg) of the glass series with GeO2 content. X-ray photoelectron spectroscopy (XPS) showed an increase in the ratio of bridging oxygens (BO) to non-bridging oxygens (NBO) with the addition of GeO2, supporting the NC and DTA results. 29Si magic angle spinning nuclear magnetic resonance spectroscopy (29Si MAS-NMR) determined a chemical shift from −80.3 to −83.7 ppm as the GeO2 concentration increased. These ionomeric glasses were subsequently used as the basic components in a series of GPCs by mixing them with aqueous polyacrylic acid (PAA). The handling properties of the GPCs resulting were evaluated with respect to the increasing concentration of GeO2 in the glass phase. It was found that the working times of these GPCs increased from 3 to 15 min, while their setting times increased from 4 to 18 min, facilitating the injectability of the Zn/Mg-GPCs through a 16-gauge needle. These Ge-Zn/Mg-GPCs were found to be injectable up to 96% within 12 min. Zn/Mg-GPCs containing GeO2 show promise as injectable cements for use in bone void filling.