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This work focus on fabrication of new Gd3+-doped willemite (Zn2SiO4) glass-ceramics derived from the Gd2O3–ZnO–Al2O3–B2O3–SiO2 (Gd-ZABS) glass system by a controlled sintering process. The physical characteristic with formation of Gd3+-doped Zn2SiO4 glass-ceramic crystal phase, morphology and structural changes were examined by Archimedes method, X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Fourier-transform infrared (FTIR) reflection spectroscopy. The appearance of SiO2, ZnO4 and Zn–O–Si bands indicate that the formation of Zn2SiO4 crystal phase. As for elastic analysis, the ultrasonic velocity and elastic coefficients showed an increasing tendency with the increase in sintering temperature. The study on energy transfer has found that the optical band gap of Gd3+-doped Zn2SiO4 glass-ceramic has decreased as the sintering temperature increased. The luminescence spectra of Gd3+-doped Zn2SiO4 exhibit several strong emission peak located at 425, 447, 462, 485 and 530 nm after the samples were subjected to 310 nm excitation source. Prominent green emission of Gd3+-doped Zn2SiO4 glass-ceramic were strongly observed at 530 nm. These spectra show that when the sintering temperature increases, the luminescence performance of the glass-ceramics has improved.

A series of zinc borosilicate glass doped with dysprosium oxide (Dy-ZBS) has been successfully fabricated through the conventional melt-quench technique with the incorporation of bio-silica source from rice husk ash. The physical, structural, luminescence, and optical properties of the fabricated glass have been studied utilizing the bulk density, x-ray diffraction pattern, photoluminescence emission spectra, chromaticity coordinates, absorption spectra, and optical band gap. The bulk density improved from 3.468 gcm− 3 to 3.635 gcm− 3 as the dopant concentration increased due to the compactness of the network structure. The amorphous nature of the glass has been justified by using an X-ray diffraction pattern. Whereas the photoluminescence emission spectra have been confirmed the presence of blue and yellow colors and were intensified as the Dy3+ increases. The CCT values from chromaticity diagram of the best white light-reaching coordinates are (0.3028, 0.3334) and classified as cool white. The optical absorbance was found to be enhanced as the Dy2O3 raised from 0 wt% to 3 wt%. Meanwhile, both the direct and indirect optical band gaps were decreased consecutively. Thus, this fabricated glass is suggested to be future solid-state light materials as a white light-emitting diode (WLED) light source.

The combined effect of MWCNTs (multi-walled carbon nanotubes) and ENIAg (Electroless Nickel Immersion Silver) surface finish on the formation of interfacial microstructure and shear strength of the Sn-1.0Ag-0.5Cu (SAC105) solder was investigated in this study. Plain and composite solders (SAC-xCNT; x = 0, 0.01, 0.05 and 0.1 wt%) were successfully synthesized through the powder metallurgy route and afterwards soldered on the ENIAg surface finish and plain Cu substrates. Detailed analysis of the microstructure revealed the formation of the Cu6Sn5 IMC at the SAC solder/Cu substrate interface of the SAC-xCNT/Cu solder interconnects. Whereas, the Ni3Sn4 IMC and (Cu,Ni)6Sn5 IMC appeared at the SAC solder/ENIAg substrate interface of the SAC-xCNT/ENIAg. The MWCNTs-reinforced SAC composite solder interconnects exhibited thinner interfacial IMC layer thicknesses relative to the plain counterparts for both substrates used. Given the prospects of the ENIAg as a reliable surface finish material, the SAC-xCNT/ENIAg exhibited IMC thickness values within the range of 2.98–2.65 µm as compared to the 5.23–3.61 µm demonstrated by the SAC-xCNT/Cu. Overall, the strengthening capacity of the MWCNTs was well-defined in both sample grades, with the SAC-0.05CNT/Cu and SAC-0.05CNT/ENIAg exhibiting the highest shear strength values of 10.23 MPa and 11.14 MPa, respectively.

Four series of CaO-ZnO-B2O3-SLS (CZBS) glasses have been synthesized by using waste materials which are eggshell (EG) and soda lime silica (SLS) glass. We utilized eggshells to source calcium oxide (CaO) in this work, whereas we utilized SLS glass to substitute silica. CZBS1, CZBS2, CZBS3 and CZBS4 are the glass series containing weight percentages of CaO (15%, 20%, 25% and 30%) and SLS (70%, 65%, 60% and 55%), respectively, with the addition of 10% of B2O3 and 5% of ZnO in each sample. A conventional melt and quenching method was applied in this work to fabricate the CaO-ZnO-B2O3-SLS glass system. The glass transition temperature (Tg) was determined using differential scanning calorimetry (DSC), which revealed that the Tg increased from 714 to 735 °C, as the CaO content increased. Meanwhile, the glass structural properties were investigated, revealing an amorphous nature with no sharp peak. The experimental elastic moduli obtained by acquiring ultrasonic speeds using the ultrasonic pulse-echo method were compared to the hypothetical elastic moduli obtained by direct estimation of the hypothetical model.

The influence of inserting WO3 in a barium-phosphate glass system (BaWP) with the chemical composition of (50-x)BaO+ (x + y)WO3 + (50-y)P2O5, where x = y and x + y = 10, 20, 30, 40, 50, and 60 mol% was evaluated. Makishima-Mackenzie's theory was applied to describe the tested BaWP glasses’ mechanical properties. The mechanical moduli (Young's, shear, bulk, and longitudinal) were predicted based on packing factor, coordination number, and the ionic radius of elements constituting the current glasses. Moreover, The shielding ability of the investigated glass samples was assessed using the Monte Carlo. The simulated results showed the best mass attenuation coefficient recorded for the BaWP7 glass sample. It is ranged between 0.3191 and 0.0517 cm2/g for gamma photons ranging from 0.284 to 1.406 MeV, respectively.

This research reports the optical and luminescence properties of new tellurite glass system with nominal composition of x(Sm2O3)–10MgO–30B2O3−(60−x)TeO2, where x = 0, 0.5, 1.0, 2.0 and 3.0 mol% synthesized via fast cooling melt-quenching method. The physical characteristic, UV–visible, refractive index, and photoluminescence spectroscopy techniques were used to examine the structural changes and optical performance of the glasses. No sharp peak appeared in the diffraction of XRD region proved the amorphous state of the glasses. The bulk density of the prepared glass samples presented an increasing trend from 4.105 to 4.403 g/cm3 meanwhile the molar volume showed opposite pattern with range value of 28.69–29.39 cm3/mol. The highest density governed by glass sample with concentration of samarium ions at 3.0 mol%, which is 4.403 g/cm3. The optical absorption spectra were characterized to determine the energy band gap, Urbach energy, and refractive index of the glasses. The obtained values for refractive index is in between 2.481 and 2.575 meanwhile for Urbach energy is 0.238–0.319 eV. The optical absorption spectra reveal eleven energy transitions bands centered at 4G9/2, 4I11/2, 4F3/2, 4G5/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2, 6F1/2 from ground state of 6H5/2. Four strong emission peaks occurred in photoluminescence, with the highest red emission peak at 600 nm. Chromaticity coordinates of the glass samples were determined as well as the dominant wavelength and colour purity, using CIE Chromaticity diagram 1931.

In this study, a promising relationship between antibacterial zone and radiation attenuation properties was investigated in Ag2O doped bioactive glasses with a chemical composition of xAg2O–20Li2O–25TeO2-(55-x)B2O3 (where x = 0, 0.5, 1.0, 1.5, and 2.0 mol%). For this aim, a wide-ranging radiation attenuation characterization procedure was performed on Ag2O substituted bioactive glasses. The general-purpose Monte Carlo code MCNPX (v.2.7.0) was used to model bioactive glasses. The mass attenuation coefficients were calculated using a gamma-ray transmission setup. The coefficients obtained were used to determine other important attenuation properties. Finally, for particular behaviors, exposure (EBF) and energy absorption (EABF) build-up factors were calculated for specific attitudes of Ag2O substitutions in bioactive glasses during the interaction process. The results showed that there is direct relationship between Ag2O substitution amount and radiation attenuation properties. In addition to its well-behaviors on inhibition zone against bacterial occurrences, it can be concluded that increasing Ag2O would increase the gamma-ray attenuation properties of studied bioactive glass system.

With the trend for green technology, the study focused on utilizing a forgotten herb to produce an eco-friendly coating. Andrographis paniculata or the kalmegh leaves extract (KLE) has been investigated for its abilities in retarding the corrosion process due to its excellent anti-oxidative and antimicrobial properties. Here, KLE was employed as a novel additive in coatings and formulations were made by varying its wt%: 0, 3, 6, 9, and 12. These were applied to stainless steel 316L immersed in seawater for up to 50 days. The samples were characterized and analyzed to measure effectiveness of inhibition of corrosion and microbial growth. The best concentration was revealed to be 6 wt% KLE; it exhibited the highest performance in improving the ionic resistance of the coating and reducing the growth of bacteria.

This study presents the utilization of mill scale waste, which has attracted much attention due to its high content of magnetite (Fe3O4). This work focuses on the extraction of Fe3O4 from mill scale waste via magnetic separation, and ball milling was used to fabricate a microwave absorber. The extracted magnetic powder was ground-milled using two different techniques: (i) a conventional milling technique (CM) and (ii) mechanical alloying (MM) process. The Fe3O4/CM samples were prepared by a conventional milling process using steel pot ball milling, while the Fe3O4/MM samples were prepared using a high-energy ball milling (HEBM) method. The effect of milling time on the structural, phase composition, and electromagnetic properties were examined using X-ray diffraction (XRD) and a vector network analyzer (VNA). XRD confirmed the formation of magnetite after both the magnetic separation and milling processes. The results revealed that Fe3O4 exhibited excellent microwave absorption properties because of the synergistic characteristics of its dielectric and magnetic loss. The results showed that the Fe3O4/CM particle powder had a greater absorption power (reflection loss: <−10 dB) with 99.9% absorption, a minimum reflection loss of −30.83 dB, and an effective bandwidth of 2.30 GHz for 2 mm thick samples. The results revealed the Fe3O4/MM powders had higher absorption properties, including a higher RL of −20.59 dB and a broader bandwidth of 2.43 GHz at a matching thickness of only 1 mm. The higher microwave absorption performance was attributed to the better impedance matching property caused by the porous microstructure. Furthermore, the magnetite, Fe3O4 showed superior microwave absorption characteristics because of the lower value of permittivity, which resulted in better impedance matching. This study presents a low-cost approach method by reutilizing mill scale waste to fabricate a high purity crystalline Fe3O4 with the best potential for designing magnetic nano-size

In this paper, the structural and optical properties of ZnO-SiO2-based ceramics fabricated from oil palm empty fruit bunch (OPEFB) were investigated. The OPEFB waste was burned at 600, 700 and 800 °C to form palm ash and was then treated with sulfuric acid to extract silica from the ash. X-ray fluorescence (XRF) and X-ray diffraction (XRD) analyses confirmed the existence of SiO2 in the sample. Field emission scanning electron microscopy (FESEM) showed that the particles displayed an irregular shape and became finer after leaching. Then, the solid-state method was used to produce the ZnO-SiO2 composite and the samples were sintered at 600, 800, 1000, 1200 and 1400 °C. The XRD peaks of the Zn2SiO4 showed high intensity, which indicated high crystallinity of the composite. FESEM images proved that the grain boundaries were larger as the temperature increased. Upon obtaining the absorbance spectrum from ultraviolet–visible (UV–Vis) spectroscopy, the energy band gaps obtained were 3.192, 3.202 and 3.214 eV at room temperature, 600 and 800 °C, respectively, and decreased to 3.127, 2.854 and 2.609 eV at 1000, 1200 and 1400 °C, respectively. OPEFB shows high potential as a silica source in producing promising optical materials.

Novel zinc alumina bismuth borate glass system was fabricated according to the empirical formula x(ZnO)–5(Al2O3)–30(BiO3)–65-x(B2O3) with x = 0, 5, 10, 15, 20, 25 and 30 mol% using conventional glass melt-quenching technique. The structural, elastic and shielding properties of the ZnO–Al2O3–BiO3–B2O3 glasses were examined by X-ray diffraction (XRD), density, molar volume, ultrasonic velocities, and EPICS2017 simulation. The glass structure's amorphous phase was confirmed by XRD measurement. From the density measurement, the addition of ZnO will increase the density from 4.275 to 5.018 g/cm3 and the molar volume decreased from 44.479 to 38.595 cm3/mol. In addition, the OPD is decreased from 67.45 to 62.19 mol/cm3. The elastic properties approximated from measured shear (VS) and longitudinal (VL) ultrasonic velocities indicated that the decrease of B2O3 in glass network cause the rigidity of glasses increased from 2300 to 2621 m/s and 4082–4540 m/s when the ZnO content increased. Meanwhile, the longitudinal (L), shear (G), bulk (K) and Young's (E) modulus increased from 71.23 to 103.43 GPa, 22.61–34.47 GPa, 41.08–57.47 GPa and 57.29 and 86.18 GPa. Besides, Poisson's ratio decreased from 0.267 to 0.250 and micro hardness increased from 3.51 to 5.75 GPa. The EPICS2017 simulation program is used to determine the radiation shielding of the glasses. The results show a very interesting results where the replacement of B2O3 by ZnO causes an improvement of the attenuation competence for the glasses.