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The present work studies the effect of CeO2 additions on the structure, properties, and shielding ability against radiation of the 30CaO–20MgO–5P2O5–45SiO2 (mol%) glass system. Five glass samples, depending on the CeO2 doping of 0.5, 1.5, 3, and 5 g on a 100% glass batch, prepared through the conventional melting process. The glasses examined using XRD, DTA, and FTIR spectroscopies with measurements of density (ρ), molar volume (Vm), and crystalline volume (Vc). Different effective radiation shielding parameters also computed via Phy-X/PSD software. The amorphous character is dominant in all tested samples. As well, CeO2 additions increase the values of ρ, Vm, and Vc. The sample coded as GCe5 (doped with 5 g of CeO2) possessed the highest values of the mass-absorption coefficient (MAC) and the sample GCe0 (free with CeO2) possessed the lowest values. The linear-absorption coefficient (LAC) parameter has the same trend of MAC. Therefore, (MAC and LAC)GCe0 < (MAC and LAC)GCe0.5 < (MAC and LAC)GCe1.5 < (MAC and LAC)GCe3 < (MAC and LAC)GCe5. Half value layers (HVLs) for the investigated glasses have an opposite trend as CeO2 increasing in the glass networks. Thus, (HVL)GCe0 > (HVL)GCe0.5 > (HVL)GCe1.5 > (HVL)GCe3 > (HVL)GCe5. Both effective atomic number (Zeff) and effective conductivity (Ceff) parameters have the same trend of MAC and LAC. Results confirmed that the investigated glasses are superior as γ-ray shields compared to some commercial concrete. Therefore, CeO2 was found in the silicate glass network as a former oxide in tetrahedral units (CeO4) and increased the bridging bonds in place of NBO in the glass network, which led to a significant increase in the γ-ray shielding properties around silicate atoms. [ABSTRACT FROM AUTHOR]

Sodium calcium silicate glasses with CdO and Fe2O3 heavy transition metals in the 16Na2O–(34 − x) CaO − xCdO–(50 − y) SiO2–yFe2O3 compositions (x = 8.50, and 17.0 mol %, and y = 2.5, 5, and 10 mol%) have been prepared using traditional melting technique. The optical properties of the prepared glasses were investigated using a UV–Visible spectrophotometer. Gamma-ray buildup factors were calculated using Phy-X/PSD software. The results of X-ray diffraction exhibited the amorphous nature for all synthesized glasses. The effect of the CdO/CaO and Fe2O3/SiO2 replacements on the linear optical properties and γ-ray buildup factors along with different mean free path values (0.5–40 mfp) of the prepared glasses has been examined. The values of the direct optical gap (Eg(d)) varied from 5.035 ± 0.001 eV to 3.94 ± 0.001 eV. The Urbach's energy EU varied randomly when using CdO and Fe2O3 instead of CaO and SiO2, which confirms a change in structural disorder in the investigated glasses. The refractive index (n) of the glass samples increased from 2.666 ± 0.001 to 3.174 ± 0.001 with the introduction of CdO and Fe2O3 into the glass matrix. The sample 16Na2O–17CaO–17CdO–47.5SiO2–2.5Fe2O3 possessed the highest values of the equivalent atomic number (Zeq) at high photon energies. In terms of exposure (EBF) and energy absorption (EABF) buildup factors, the sample coded as D6 had the lowest EBF and EABF values among all the samples examined. Overall, the findings indicate that CdO/CaO and Fe2O3/SiO2 replacements improve enhancing optical and radiation shielding abilities. Finally, these findings have the potential to position these newly prepared glasses as promising optical and shielding materials with the lowest fabrication cost for various protective applications in different fields. [ABSTRACT FROM AUTHOR]

In the present study, a novel glass system containing Neodymium(III) oxide with BaO, Al2O3, and B2O3 were created via a popular melt-quenching technique. Nd2O3 were added, in different concentrations, instead of B2O3 to study its impact on the crystallization, and electro-magnetic behaviors of the prepared poly-crystalline materials. Thermal characteristics via DTA, XRD and SEM techniques were involved to explore the crystallization and structural properties. The magnetic parameters of the prepared glass–ceramics were studied by VSM measurements. As well the electric properties were also explored. BaB2O4 and Al(BO3) phases were firstly crystallized then Ba3Nd(BO3)3 phase was incompletely precipitated instead of BaB2O4 phase owing to Nd2O3 additions. As well, the internal structure was modified from coarse crystals to fine grain microstructure. The crystallization study proved that the addition of neodymium improved the crystallization process of the BaO–Al2O3–B2O3 glass system. The VSM and conductivity analysis for the crystalline materials proved that the Nd2O3/B2O3 substitutions led to an increase in the electrical and magnetic parameters of the investigated materials. The data obtained from the prepared crystalline specimen showed that these materials are with a distinct and promising ferro-electrical property for use in diverse modern applications. [ABSTRACT FROM AUTHOR]

Glasses with desirable structural, thermal, and microhardness properties were prepared in the 16Na2O-(34-x)CaO-xCdO-(50-y)SiO2-yFe2O3 system, where x = 0, 8.5, and 17; Y = 2.5, 5, and 10 mol.%. The glasses were synthesized using the melting method and characterized via x-ray diffraction (XRD), Fourier transform infrared (FTIR), and differential thermal analysis (DTA). Physical properties such as density (ρ) and molar volume (Vm) were shown to be compositionally dependent on the CdO and Fe2O3 content. Thermal characteristics were demonstrated as well. The XRD patterns confirmed the amorphous nature of all glasses. The density (ρ) increased from 2.75 g/cm3 to 3.38 g/cm3, whereas the molar volume (Vm) decreased from 57 cm3/mol to 36 cm3/mol, both of which exhibited the great compactness of the glass structure. The composition of the studied glass was modified using cadmium and iron oxides instead of CaO and SiO2 , leading to a decrease in glass transition (Tg) and crystallization (Tc) temperatures and enhanced devitrification. This was accomplished by increasing the thermal expansion coefficient (α) values (from 33 × 10–7 C−1 to 72 × 10–7 C−1). Consequently, Vickers microhardness (Hv) values were found to decrease gradually from 5243 MPa to 4174 MPa. The mass attenuation coefficient (MAC) was enhanced by increasing the density and Fe2O3 content in the proposed glasses. The half-value layer (HVL) followed the trend (HVL)D1 > (HVL)D2 > (HVL)D3 > (HVL)D4 > (HVL)D5 > (HVL)D6. The mean free path (MFP) showed a similar trend as the HVL. The trend of the effective atomic number (Zeff) was the same for both MACs. Results confirm that the proposed glasses (D1–D6) can be applied as radiation shielding materials in the medical and industrial fields. [ABSTRACT FROM AUTHOR]

The main goal of this study is to comprehend the effect of the composition change on crystallization characteristics, thermal, physical, and magnetic properties of glasses with the general formula (35 − x) Li2O − (5 + x) NiO − 60 P2O5 (x = 5, 10, and 15 mol%). The XRD results indicated that Li4P4O12, Li6P6O18, Ni2P2O7, Ni2P4O12, and Li3P crystalline phases were formed in the glass ceramics. The NiO/Li2O replacement led to an increase in the coherence of the glass structure. Density values for the glass and glass–ceramic samples ranged from 2.38 to 2.49 g/cm3 and from 2.41 to 2.53 g/cm3, respectively. Coefficients of thermal expansion CTE of the glasses were varied from 157 × 10−7 to 96 × 10−7 °C over the temperature range of 25–250 °C. However, CTE of the glass–ceramic was ranged from 183 × 10−7 to 129 × 10−7 °C over the temperature range of 25–500 °C. VSM analysis for the glasses revealed that the NiO/Li2O replacement led to a decrease in the magnetic parameters of the materials. Contrariwise from VSM hysteresis loops of glass–ceramic, it was found that the magnetic parameters increased with the addition NiO instead of Li2O. The results indicated a great potential of the prepared glasses and glass ceramics as promising soft ferromagnetic materials that can be used in different magnetic applications. [ABSTRACT FROM AUTHOR]

Glasses having a chemical composition based on combeite [Na2Ca2Si3O9]–fluoroapatite [Ca5(PO4)3F] and forsterite [Mg2SiO4] system were crystallized through controlled heat-treatment. Two forms of sodium calcium silicate e.g. combeite Na2Ca2Si3O9 and pectolite Na2CaSi3O8, were formed together with diopside (CaMgSi2O6) and monticellite (CaMgSiO4) in addition to fluoroapatite (Ca5(PO4)3F) phases by thermal treatment of the glasses. Selected glass–ceramics were exposed to a simulated body fluid solution (SBF) which is close to human plasma for 3 weeks. Energy dispersive X-ray analysis (EDX) and inductive coupled plasma (ICP) analysis confirmed the formation of an apatite layer which indicate bioactivity in the all crystallized sample. A decreasing of surface bioactivity with increasing Mg2SiO4/Na2Ca2Si3O9 replacement was observed as indicated by the decrease in the amount of apatite layer on the surface of the crystallized specimens. The Vicker’s microhardness of the studied glass–ceramic materials are between 5,047 and 6,781 MPa. [ABSTRACT FROM AUTHOR]

The inhibitive and adsorptive characteristics of ethanol extract of fennel seeds for the corrosion of 304 stainless steel (SS) in 1M HCl solutions have been studied using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy, and electrochemical frequency modulation methods for monitoring corrosion. Ethanol extract of fennel is a good adsorption inhibitor for the corrosion of 304 SS in HCl. The inhibitive property of the extract is attributed to the presence of anethol and fenchone as major constituents in the extract. Inhibition efficiency increased with increasing concentration of the extract but decreased by increasing the temperature. Adsorption studies revealed that Langmuir adsorption isotherm is the best adsorption model applicable to the adsorption of fennel extract on 304 SS surface. Activation and adsorption parameters were evaluated and discussed. Potentiodynamic polarization measurements indicated that the inhibitor is of mixed type. The results obtained from these techniques were in good agreement to prove the validity of these tools in the measurements of the tested inhibitor. [ABSTRACT FROM AUTHOR]