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The simulation-based artificial neural networks (ANN) program is one of the suitable candidates from artificial intelligence simulation which can work to predict important ultrasonic and mechanical parameters in the glass field. This research is focused on exploring the validity of this system by comparing the prediction values from ANN with the experimental measurements and other theoretical models. The ANN simulation was effectively applied to a binary zinc-borate glass system with the composition of zZnO−(100-z)B2O3 where z = 0, 40, 45, 50, 55, and 60 mol%, which was fabricated by using the melt-quenching techniques. The increase of ZnO content caused the ultrasonic velocity and elastic moduli of the glasses to exhibit a decreasing trend. The bond compression theoretical calculation compared with the experimental measurement was considered to be satisfactory with the value of the coefficient R2 being around 0.92452 to 0.98492. The Makishima-Mackenzie calculation model concerning the experimental measurement of the elastic moduli and Poisson's ratio were between 0.86628 to 0.99786. The coefficient R2 value from the ANN simulation displayed on the density, ultrasonic velocity, and elastic moduli graph is around 0.9999 to 1.0000, which is considered to be very reasonable. The values predicted by this remarkable model proved that ANN simulation is suitable for use in glass research.

A system of bio-silica borotellurite glasses was fabricated based on the chemical formula [(TeO2)0.7 (B2O3)0.3]1-x (SiO2)x with x = 0.1, 0.2, 0.3, and 0.4 using the melt-quenching technique using silica (98.548% SiO2, from rice husk), TeO2 (Alfar Aeser, 99.9%) and B2O3 (Alfar Aeser, 99.9%). Measurements and characterizations such as density and molar volume measurements, XRD analysis, FTIR, and UV–Vis spectroscopes were performed on the studied glasses. The objective was to determine the glasses’ applicability in optoelectronics, non-linear optics, and laser technologies through polarizability, linear electric susceptibility, and optical basicity study. Apart from confirming the amorphous nature of the glasses, the XRD analysis identified the presence of a crystalline phase of tellurium oxide (α-TeO2) formed. The FTIR spectral study revealed the presence of TeO3, BO3, and SiO4 structural units in the studied glasses. The refractive index (2.3026 – 2.2651), molar polarizability (8.0696 – 9.4334 A3), oxide ion polarizability (3.2970 – 3.6202 A3), electronic polarizability (0.2296 – 0.2335 A3), dielectric constant (5.1307 – 5.3019), optical basicity (0.6719 – 0.7998), metallization criterion (0.410853 – 0.420714) and electric susceptibility (0.3286 – 0.3422 esu) of the glasses were presented. With the high refractive index and favourable electronic/oxide ion polarizability as well as good electric susceptibility, the glasses have shown great potential for optical fibre and laser applications. Metallization criterion value falls in the range of glasses with great potentials for non-linear optical application. The dielectric value suggests the glasses represent wideband semiconducting glasses believed to be good for application in microelectronic substrates fabrication.

Erbium nano particles (NPs) doped tellurite glasses were prepared via melt-quenched technique and their chemical composition are as follows; {[(TeO2) 0.70 ( B 2 O3) 0.30 ] 0.7 (ZnO) 0.3 } y (Er2O 3 NPs) 1−y , y = 0.005, 0.01, 0.02, 0.03, 0.04 and 0.05. The amorphous state of the glass system was revealed and the structural parameters indicating the formation of non-bridging oxygen was shown. The current work underlines the spectral parameters from Judd–Ofelt (JO) studies, and upconversion spectra. The existence of erbium NPs was found experimentally using transmission electron microscopy (TEM). The Judd–Ofelt analysis suggests that the radiative probability, A rad is strong at 2H 11∕2 —> 4I 15∕2 and a longer lifetime at 4I 11∕2 —> 4I 15∕2 . The Argon laser beam was used to determine the upconversion emission peaks. The upconversion radiation emission excited at 800 nm was found in the range 390 nm.

Ascertaining plasmonic interaction induced by silver (Ag) and gold (Au) nanoparticles (NPs) in the amorphous system can open a new direction in photonics. In this outlook, various contents of Ag and Au NPs were incorporated into neodymium ions (Nd3+)-doped zinc-sulfate-magnesium-phosphate glasses via the melt-quenching method. The impact of Ag–Au plasmonic coupling on the structures and spectroscopic traits of the prepared glasses were evaluated. As-quenched samples were analyzed using XRD, HRTEM, Raman, absorption and photoluminescence (PL) spectrometer. The Judd-Ofelt (JO) theory was used to evaluate the spectroscopic quality and stimulated emission cross-section of the glasses. HRTEM micrographs verified the existence of Au and Ag NPs in the glass matrix with a mean size ranged 4.47–7.03 nm. The observed thirteen absorption bands centered around 326, 352, 430, 459, 473, 512, 52, 581, 627, 681, 744, 801, and 875 nm were corresponding to electronic transitions from the ground state (4I9/2) to the excited states of 4D7/2, 2D1/2+4D3/2+4D5/2, 2P1/2, 4G11/2, 2D3/2+2P3/2+2G9/2, 4G9/2+2K13/2, 4G7/2, 4G5/2+2G7/2, 2H11/2, 4F9/2, 4F7/2+4S3/2, 4F5/2+2H9/2 and 4F3/2 in Nd3+. Two surface plasmon resonance (SPR) bands assigned to Ag and Au NPs were probed at 442 nm and 503 nm. The addition of Au NPs causes the SPR band of Ag NPs to be red-shifted. The NIR PL bands at 878 nm, 1050 nm and 1322 nm were due to the 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 transitions, respectively. The PMZ1.5Nd0.5Ag0·1Au glass disclosed the highest bandwidth gain of 6.92, 17.05 and 9.10 ( × 10−23 cm3) corresponding to the 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 transitions. It was shown that the PL intensity of the studied glasses could be modified by varying Ag and Au NPs contents. The Ag–Au NPs plasmonic coupling inclusion inside the glass can be beneficial to develop versatile optical materials.

In this study, the effect of biscyclopentadienyl magnesium flow rate for the growth of p-type gallium nitride thin films was varied from 20 to 40 standard cubic centimeter per minute to acquire the optimum doping concentration level. The growth of semi-polar (11–22) p-type gallium nitride thin films on m-plane sapphire was accomplished via metal organic chemical vapor deposition. Atomic force microscopy reveals the occurrence of dissimilar grain size distributions upon the utilization of different dopant flow rates. Statistical data shows that the utilization of optimized biscyclopentadienyl magnesium flux of 30 standard cubic centimeter per minute would significantly reduce the grain size to as low as ∼ 550 nm (±1 nm), yielding a root mean square roughness of 6.00 nm. X-ray rocking curve analysis observed that a moderate biscyclopentadienyl magnesium flow rate of 30 standard cubic centimeter per minute leads to narrowing in full width at half maximum, indicating an enhanced crystallinity with a reduction of the basal stacking fault density of 8.18 × 104 cm−1 with the use of 30 standard cubic centimeter per minute of biscyclopentadienyl magnesium. Moreover, the mobilities and carrier concentrations were improved to as high as 1.8 cm2.V − 1.s − 1 and 5.5 × 1017 cm−3 with a moderate biscyclopentadienyl magnesium flow rate of 30 standard cubic centimeter per minute. The analysis suggests that with the optimum biscyclopentadienyl magnesium flow rate (30 standard cubic centimeter per minute), preferential sites for magnesium incorporation can be enhanced.

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.

The ores of Big Karatau are a valuable, currently unused source of rare and rare earth elements (REEs). To develop an integrated technology for processing black shale ore, it was studied using chemical, X-ray phase, infrared, mineralogical, X-ray spectral, and electron microscopic analyses. Rare and particularly REEs in the ore are found in various minerals in the form of inclusions in the siliceouscarbonaceous matrix. This explains the failures of the previously proposed processing methods, which either resulted in the incomplete extraction of the valuable components or were not profitable. For more complete extraction, novel ore processing approaches are required. A method for the early development of the original black shale ore using sintering with (NH4)2SO4 in the presence of concentrated H2SO4, followed by leaching of the cake with a diluted H2SO4 solution, is proposed. The optimal conditions for each stage are determined. The kinetic dependencies of the extraction of rare and REEs from sulfated cake under the most suitable conditions yielded maximum extractions of 98% for U, 92% for V, 89% for Mo, and 78% for the REEs. The rate constant and effective activation energy of V leaching, as the most representative of the rare and rare earth metals, were calculated. The process was limited by diffusion. After the leaching of the valuable components, the cake may be used in froth flotation enrichment to recover the carbonaceous material, and then it may be used as part of the charge to obtain ferrosilicon. The solution obtained from the leaching of the initial cake may be used to recover U, Mo, V, and the REEs using sorption.

Judd–Ofelt (J–O) theory was used to analyze the optical properties of erbium (Er3+) ions doped zinc-sodium-tellurite glass system incorporated with titania (TiO2) nanoparticles (TNPs) for the realization of up-converted solid state lasers. Such glass systems were synthesized using melt quenching method to determine the influence of varying TNPs contents on the absorption and emission properties. J-O intensity parameters (Ω2, Ω4, Ω6), spectroscopic quality factor (χ = Ω4/Ω6), radiative transition probabilities, branching ratio, and radiative lifetime of various transitions involved in the Er3+ ions were calculated from the measured optical spectra. XRD pattern verified the amorphous nature of the prepared glass samples. TEM images manifested the growth of TNPs inside the glass matrix having mean size between 15 and 25 nm. UV–Vis–NIR spectra exhibited ten absorption bands centred at 407, 444, 452, 489, 522, 552, 653, 800, 976 and 1532 nm. Two surface plasmon resonance (SPR) bands of TNPs were evidenced at 552 nm and 580 nm. Luminescence spectra revealed three prominent peaks centred at 525, 545 and 660 nm, where the glass sample containing 0.2 mol% of TNPs displayed optimum intensity enhancement by a factor of 30.00, 28.57 and 19.60, respectively. This enhancement is primarily attributed to the TNPs surface plasmon enabled colossal localized electric field in the proximity of Er3+ ions and subsequent energy transfer to the Er3+ ions. Values of Ω2, Ω4, Ω6 and χ were ranged between (2.14−3.72)×10−20, (1.27−2.77)×10−20, (1.42−2.22)×10−20 cm2 and (0.58–1.94), respectively. Occurrence of higher values of Ω2 and Ω6 indicated the existence of lower symmetry and stronger covalency around the Er3+ ions. Furthermore, the decrease of χ values with increasing TNPs up to 0.2 mol% approved intensified lasing transition. Achieved higher values of Ω4 and Ω6 demonstrated that the present glass composition is a prospective lasing media.

Neodymium oxide doped tellurite-based glass has been widely documented for potential uses in optoelectronics, but graphene oxide (GO)-coated tellurite-based glass has rarely been reported. In this work, we compare two sets of glass series which were GO-coated and uncoated tellurite-based glass series denoted as ZBTNd-GO and ZBTNd, respectively. The two sets of glasses were fabricated via melt-quenched process. A set of glass was coated with GO using low-cost spray coating method. The structural and morphological properties of the glass samples were investigated to confirm the type of structure in glass and formation of graphene oxide on glass surface. The X-ray diffraction (XRD) pattern confirmed the amorphous structural arrangement in both sets of glass series. The morphological study proved the existence of GO layers on top of the ZBTNd-GO surface. The optical bandgap energy of ZBTNd-GO glass was found in the range of 3.253 eV–3.381 eV which was higher than ZBTNd glass. Meanwhile, the refractive index of ZBTNd-GO glass varies from 2.301 to 2.332 which was higher than ZBTNd glass due to the presence of functionalized oxygenated groups in GO structure. The oxide ion polarizability of ZBTNd-GO glass was found decreased due to the shift of optical band gap when coated with GO. This work offers a new form of glass that could be used as a new strategy to upgrade the current photonic materials.

A glass series of erbium doped zinc borotellurite glass system was prepared by using the melt-quenching method. The absorption spectra revealed several bands at visible range which correspond to the following transitions (from the ground state); 4G11/2 + 2H9/2 + 4F5/2 + 4F7/2 + 2H11/2 + 4S3/2 + 4F9/2 + 4I9/2 + 4I11/2. From the Judd–Ofelt analysis, it is found that the trend of Ω2 values is a non-linear variation along with erbium concentrations. Meanwhile, the value of Ω6 decreases as the erbium concentration increases. The photoluminescence analysis shows green emission which are attributed to the 4S3/2 level to the ground state at 4I15/2. Meanwhile, the upconversion analysis revealed several emission bands at 376 nm, 424 nm, 470 nm and 558 nm which correspond to 4G11/2 → 4I15/2, 4F3/2 → 4I15/2, 4F7/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions respectively. The non-linear refractive index spectra show self-defocusing behavior and negative nonlinear refraction (ƞ2

Zinc borotellurite glasses doped with lanthanum oxide were successfully prepared through melt-quenching technique. The amorphous nature of the glass system was validated by the presence of a broad hump in the XRD result. The refractive index of the prepared glass samples was calculated by using the equation proposed by Dimitrov and Sakka. The theoretical value of molar refraction, electronic polarizability, oxide ion polarizability and metallization criterion were calculated by using Lorentz-Lorenz equation. Meanwhile, expression proposed by Duffy and Ingram for the theoretical value of optical basicity of multi-component glasses were applied to obtain energy band gap based optical basicity and refractive index based optical basicity. The optical basicity of prepared glasses decreased with the increasing concentration of lanthanum oxide. Metallization criterion on the basis of refractive index showed an increasing trend while energy band gap based metallization criterion showed a decreasing trend. The small metallization criterion values of the glass samples represent that the width of the conduction band becomes larger which increase the tendency for metallization of the glasses. The results obtained indicates that the fabricated glasses have high potential to be applied on optical limiting devices in photonic field. Keywords: Borotellurite glasses, Refractive index, Electronic polarizability, Oxide ion polarizability, Optical basicity, Metallization criterion

Efficient, inexpensive and eye−safe new host glass as up−conversion (UC) emission solid−state laser media became demanding. Nanoparticles (NPs) of various noble metals have been inserted into the phosphate−based amorphous host matrix to enhance the rare-earth ions (REIs) stimulated emission cross−section. Furthermore, only a few reports exist on the combined influences of neodymium ions (Nd3+) and pure silver (Ag) NPs on the structural and optical response of magnesium zinc sulfophosphate (MZSP) glasses. In this view, a series of MZSP glasses were doped by Nd3+ ions and pure Ag NPs (at different concentrations) to improve their structural and optical properties. Such melt−quench synthesized glasses were characterized at room temperature using diverse analytical measurement tools. The XRD pattern of as−quenched samples approved their amorphous nature. The FTIR and Raman spectra of glasses revealed the presence of characteristic bonding vibrations of different functional groups. The TEM images showed the existence of spherical Ag NPs (mean size of 8.34 nm) in the host glass matrix. The surface plasmon resonance (SPR) band of Ag NPs was detected around 451 nm. The UV–Vis–NIR absorption and PL emission spectra of glasses were utilized to evaluate the Judd−Ofelt (JO) intensity parameters ( Ω 2 , Ω 4 and Ω 6 ) and radiative properties. The observed fluctuation in the Ω 2 values with the increase in Ag NPs contents was attributed to the dynamic change of ligands symmetry around Nd3+ inside the glass network. Variations in the Ω 4 and Ω 6 values with the increase in Ag NPs contents indicated a considerable reduction in the glass rigidity. The PL spectra of glasses exhibited a prominent band around 576–584 nm corresponding to the 2G7/2 +4G5/2 → 4I9/2 transition in Nd3+. Glass prepared with 0.5 mol% of Ag NPs disclosed the highest PL enhancement (≈19 times) and largest emission cross−section (≈4.35 × 10−24 cm2) which was ascribed to the synergism between Ag NPs SPR mediated strong local field effect (LFE) and the subsequent energy transfer to Nd3+ appeared in the proximity of NPs. It was concluded that the proposed glass composition can lead to the development of UC solid−state laser compared to many other reported glass system.

In this work, we synthesize graphene oxide (GO)-coated tellurite glass for the improved optical performance of fiber optics. A series of tellurite glass system with composition of {[(TeO2)0.7 (B2O3)0.3]0.7 (ZnO) 0.3}1-y (Er2O3) y where y (mol%) = 0.005, 0.01, 0.02, 0.03, 0.04and 0.05 mol% was successfully fabricated and coated with GO by using melt-quenching and spray coating methods. The structural properties were characterized by using XRD analysis and FESEM. The XRD patterns indicated that the tellurite glass were amorphous. The FTIR transmissions images revealed the surface morphology of GO on the glass surface. The optical band gap energy was found enhanced from 3.392 to 3.495 eV. The refractive index was found improved from 2.275 to 2.299 with the existence of GO. Hence, these results were useful for the application of fiber optics.

In this work, linear and nonlinear optical parameters of zinc borotellurite glasses doped with Gd3+ have been studied for all-optical switching applications. A series of gadolinium zinc borotellurite glasses were synthesized by using conventional melt quenching technique. Optical absorption spectra were recorded by UV–vis spectroscopy. From the optical absorption spectra, the cut-off wavelength, optical band gap, Urbach energy and refractive index have been determined and are related to the structural changes in the glass systems. The nonlinear optical properties of Gd3+ doped glasses are investigated by using Z-scan technique. The values of nonlinear refractive index and absorption coefficient with closed and opened apertures of the Z-scan, respectively, were determined for proper utilization in nonlinear optical devices. Keywords: Gadolinium, Rare earth, Borotellurite glass, Optical band gap, Refractive index, Nonlinear optical properties

A series of neodymium NPs doped tellurite glass with composition of (TeO2)0.7(B2O3)0.3]0.7 (ZnO)0.3}1- x (Nd2O3 NPs) x (x = 0.005, 0.01, 0.02, 0.03, 0.04 and 0.05 mol%) was fabricated via melt-quenching method. Density and molar volume were measured and analyzed for the glass series. The optical properties of neodymium NPs doped tellurite glass were measured by UV–Vis spectrometer, photoluminescence and Z-scan technique. The optical band gap energy of the glass network was in the range of 3.178–3.209 eV. The upconversion emission of the laser glass excited at 800 nm was found in the ultraviolet region. Electronic polarizability, oxide ion polarizability, optical basicity and metallization criterion were calculated. Moreover, linear absorption coefficient, α, nonlinear refractive index ƞ (cm2/W), nonlinear absorption, β (x 10−3) and third order susceptibilities, χ (x 10−6) were measured. The optical efficiency of neodymium NPs doped tellurite glass exhibited excellent properties for its application in laser glass.

Successful extraction of high purity SiO2 (about 99%) from rice husk (waste) was achieved in this work using the cold acid leaching method. Glass series [(TeO2)0.7 (B2O3)0.3]1-x (SiO2)x were fabricated using the rice husk silicate (RHS) by melt-quenching method. The samples were subjected to X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) characterization to study the structural nature of the glass system. Density and ultrasonic velocities were measured to obtain the elastic constants for the various silicate proportions in the glass using ultrasonic data obtained from non-destructive ultrasonic probing technique. The elastic moduli calculated from the obtained data were found to have increased with the addition of more RHS in the glass. Other parameters studied include the microhardness (H), Poisson's ratio (σ), softening temperature (ϴD) and fractal bond connectivity (d) and the fluctuation free volume (fugacity, fg). A very unusual occurrence was observed as microhardness value decreases in the glass system as more RHS (SiO2) is introduced. The quality of the glass in terms of elastic behavior improved with addition of RHS in the borotellurite glass network.

The glass series with composition of {[(TeO 2 ) 0.70 (B 2 O 3 ) 0.30 ] 0.7 (ZnO) 0.3 } 1-y (Nd 2 O 3 ) y where, y = 0.005, 0.01, 0.02, 0.03, 0.04 and 0.05; was fabricated via melt-quenched technique. The third-order optical nonlinearity was observed by using Z-scan technique. Polarizability and third-order nonlinearity of borotellurite glass doped with neodymium (Nd 3+ ) will be reported. This work presents the effect of neodymium ions on the linear and nonlinear optical performance of borotellurite glass for potential photonics applications. The structure and optical performance of the resulting transparent neodymium doped borotellurite glass are characterized. The reduction of optical band gap energy, E g is observed which shows the alteration of tellurite structure by the Nd 3+ . The values of electronic polarizability are enhanced with an increase of Nd 3+ ions. The enhancement of electronic polarizability provides an excellent medium for nonlinear optical applications. The optical basicity of the investigated materials shows non-linear trend along with Nd 3+ ions concentration. The Z-scan data for third-order optical nonlinearities suggest that the glass materials are excellent to be used as a medium in nonlinear optical fiber. Therefore, the investigated glass materials may provide a good material for photonic applications.