Showing papers in "Journal of Non-crystalline Solids in 2020"

Effect of chromium oxide on the physical, optical, and radiation shielding properties of lead sodium borate glasses

Abstract: In this paper, we prepared lead sodium borate glasses modified with different amount of chromium oxide according to (50-x)B2O3+ 40PbO+ 10Na2O2+ xCr2O3, where x=0, 0.5, 1, 1.5, 2, 2.5 wt%. The current glasses were prepared by melting the stoichiometry at 1050 °C, quenching into the water, and annealing for five hours at 250 °C. The amorphous state was proved by applying the X-ray diffraction test. The physical parameters such as density and molar volume were evaluated for each glass. The optical parameters such as bandgap, Urbach energy, refractive index, dielectric constant, reflection loss, molar polarizability, molar refractivity, optical dielectric constant, optical electronegativity, electron polarizability, optical basicity, metallization, and cut-off wavelength were obtained based on JASCO UV–Vis–NIR spectrophotometer. The shielding studies included gamma, electron, proton, and neutron radiations. The newly developed Phy-X/PSD and Phy‐X/ZeXTRa programs along with Geant4 simulations were used to estimate the radiation shielding parameters such as the attenuation and transmission factors. The effect of Cr2O3 content on the optical and radiation shielding properties was determined and well interpreted. The radiation shielding features of the prepared glasses were compared with those of various ordinary concretes, and Pb-free, Pb-based, and commercial glasses. The results revealed that the lead sodium borate glasses modified with chromium oxide could be useful for the shielding applications against gamma, electron, and neutron radiations, wherein the Cr2O3 content can be balanced according to the type and energy of incident radiation.

Novel vanadyl lead-phosphate glasses: P2O5–PbO–ZnO Na2O–V2O5: Synthesis, optical, physical and gamma photon attenuation properties

Abstract: A novel glass of Vanadyl lead-phosphate with the chemical formula P2O5–(40-x) PbO–ZnO Na2O–xV2O5 where x = 0, 0.2, 0.4, 0.8, 1.5, and 2 wt% have been synthesized using melt-quenching method. The amorphous nature of the prepared glasses was examined via XRD spectra. UV–vis spectra were recorded in the range of 190–1100 nm wavelength. The optical energy band gaps and refractive index via Tauc's model, absorbance spectrum fitting (ASF), and the first derivation of the absorption spectrum fitting (DASF) have been determined for all glasses. Gamma-photons shielding capability of the fabricated glasses have been evaluated using MCNP-5 code. Furthermore, different shielding factors were calculated. The geometric progress fitting parameters, exposure and energy absorption buildup factors were also computed using newly created program Phys-X/PSD. The results show that energy gaps for all glasses were close together, but the index of refraction was high. In addition, the shielding properties of the fabricated glasses decreases with increase the vanadium pentoxide content in the fabricated samples. The glasses without vanadium pentoxide had the best shielding capacity among the synthesized vanadyl lead-phosphate glasses. The buildup factors were observed to decrease with increase the vanadium pentoxide. Comparison of the synthesized glasses with standard references material and previously synthesized glasses showed that the Vanadyl lead phosphate glasses can be used as a radiation shielding material.

Investigation of optical, physical, and gamma-ray shielding features of novel vanadyl boro-phosphate glasses

Abstract: In this paper, novel vanadyl boro-phosphate glasses with the chemical formula (100 − x)(0.5V2O5 -0.5P2O5)-xB2O3 (x = 0, 2, 4, 6, 8 mol%) have been synthesized using melt-quenching method. The amorphous state of the glasses was checked through XRD measurements. UV–vis spectra were recorded in the range of 200–1100 nm wavelength. The optical energy band gaps via Tauc's model, absorbance spectrum fitting (ASF), and the first derivation of the absorption spectrum fitting (DASF) methods have been calculated for all glasses. Urbach's energy and refractive index of the prepared glasses also calculated. Gamma-photons shielding capability of the proposed glasses have been evaluated in terms of mass attenuation coefficient (μ/ρ) which calculated using WinXCOM software. Based the (μ/ρ), half value layer (HVL), mean free path (MFP), and effective atomic number (Zeff) were calculated. The results show that energy gaps for all glasses were close together, but the index of refraction was high around 4. Results of HVL, MFP, and Zeff confirmed that VPB0 glass sample (free with boron) has good attenuation capability compared to other VPB (with boron additions) glasses. Moreover, gamma-ray protection ability of the current glasses was compared with that of some commercial glasses. It can be concluded that the prepared glass samples could be useful to design or develop novel shields for radiation protection applications.

Radiation shielding features of zirconolite silicate glasses using XCOM and FLUKA simulation code

Abstract: This work aimed to investigate the ionizing radiation shielding features of zirconia silicate SiO2 Na2O CaO —xZrO2 (SCNZ) glass system The mass attenuation coefficients (μ/ρ) were generated by FLUKA Monte Carlo simulation code and the obtained data was verified via the calculated data from XCOM software over an extended photon energy range of 0015 – 20 MeV The obtained values of μ/ρ were used to evaluate several important shielding parameters such as half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), and effective electron density (Neff) Results reveal that μ/ρ, MFP, HVL, Zeff, and Neff of the investigated glasses strongly depend on photon energy and chemical composition Additionally, by using GP fitting parameters, the exposure buildup factor (EBF) of the investigated glasses were calculated Results show that the greatest values of buildup factors exhibit at higher energies for all glass samples Finally, the values of fast neutron removal cross section (ΣR) and the kinetic energy loss rate (Mass Stopping Power, MSP) of alphas and protons passing through the studied glasses were evaluated Results display that the insertion of ZrO2 improves the nuclear shielding capability of SCNZ glasses Especially, SCNZ7 glass owns superior shielding ability for charged particles as well as gamma radiation

Investigation of mechanical and radiation shielding characteristics of novel glass systems with the composition xNiO-20ZnO-60B2O3-(20-x) CdO based on nanometal oxides

Abstract: Novel glass systems with the compositions xNiO-20ZnO-60B2O3-(20-x) CdO (0 ≤ x ≤ 5 mol%) have been designed and assembled by the melt quenching technique from different nanometal oxides (NiO, ZnO, B2O3, and CdO) to serve as competitive candidates for radiation shielding. The X-ray diffraction technique was utilized to confirm the amorphous character of the samples. The target metal oxides (ZnO, NiO, CdO and B2O3) were synthesized in the nanoscale, as confirmed by SEM analysis. The mechanical properties of the new composites have been studied and their elastic moduli have been estimated. Enhancement in the elastic moduli, density and physical properties were achieved by the assembled systems. The density was varied between 3.72 and 4.27 g/cm3, whereas molar volume decreased from 22.51 to 19.53 cm3 mol−1, as the loading of NiO NPs increased from 0 to 5 mol% in the composite. The mass attenuation coefficients (µm) have been measured at different γ-ray photon energies (662, 1173 and 1332 keV) using narrow beam transmission geometry and the results have been compared with those obtained by XCOM simulation code to confirm a good match between the values. Measurements referred to the increase in some parameters of the new glasses, including the mass attenuation coefficient (µm), effective atomic number (Zeff) and effective electron density (Nel) due to the increase in NiO content from 0 to 5 mol%. Additionally, the half value layer (HVL) and the mean free path (MFP) were decreased with increasing NiO percent content. The achieved results denote that 5NiO-20ZnO-60B2O3-15CdO exhibited the best radiation shielding characteristics among the tested glasses. Finally, the radiation shielding characteristics of the new glass systems have been compared with the previously studied standard glasses to refer to the superiority of the assembled systems.

Physical and optical properties of a-Ge-Sb-Se-Te bulk and film samples: Refractive index and its association with electronic polarizability of thermally evaporated a-Ge15-xSbxSe50Te35 thin-films

Abstract: This work is dedicated to the deduction of many basic physical parameters of a-Ge15-xSbxSe50Te35 bulk and thin-film samples, GSST (0.0 ≤ x ≤ 15.0 at.wt.%). Besides, study the interrelationships among refractive index, molar refractivity and electronic polarizability of these film samples. Solid-state solutions of GSST compositions were prepared followed by melt-quenching method to get the glassy bulk samples. The thin-film samples of thickness 200 nm were fabricated by thermal evaporation technique. X-ray diffractograms revealed that all prepared GSST bulk and film samples are of non-crystalline nature. The ingots bulk Ge-Sb-Se-Te samples have been used to practically estimate the density. The refractive index of Ge15-xSbxSe50Te35 amorphous thin-films have been utilized to discuss the electronic polarizability, Covalence parameter and optical electronegativity. As well as, the deviation from stoichiometry, average heat of atomization, the overall mean bond energy and the glass transition temperature are also evaluated. All studied parameters are highly dependent on the Sb-ratio.

Role of ZnO on TeO2.Li2O.ZnO glasses for optical and nuclear radiation shielding applications utilizing MCNP5 simulations and WINXCOM program

Abstract: The role of ZnO on the [(100-(X + 15)] TeO2-15Li2O-XZnO: X = 00, 05, 10, 15, 20, and 25 mol% (TLZ) glasses for optical and gamma-rays shielding applications was investigated. Molar refraction and molar polarizability (RMolar, αMolar); Dielectric coefficients and metallization principle (eStatic, MCriterion); Optical transmission and reflection loss (TOptical, RLoss); Metallization property according to refractive index and optical energy gap (M(nLinear), M(EOptical)) were investigated. The nuclear radiation shielding features were investigated for the proposed glasses utilizing MCNP5 simulations and WinXCOM program. The mass attenuation coefficient and effective atomic number ((μ/ρ, Zeff); Half-value layer and mean free path (HVL, MFP); Energy-absorption buildup factor and exposure buildup factor (EABF, EBF) were evaluated for all TLZ glasses. Results revealed that the RMolar changed from 15.981 to 18.70 cm3/mol, while αMolar changed from 6.342 to 7.250×10−24 cm3 for TLZ60 to TLZ85. The TOptical varied from 0.751 to 0.739, while RLoss varied from 0.141 to 0.150. All studied samples are in non-metallic (insulator) nature where RMolar values are smaller than that of VMolar (24.234–27.138 cm3/mol). TLZ glasses with the highest concentrations of ZnO have the highest (µ/ρ) values and lowest HVL and MFP. Thus, TLZ glasses exhibit higher shielding capacity among other commercial materials as RS-360.

Newly developed tellurium oxide glasses for nuclear shielding applications: An extended investigation

Abstract: Newly developed glasses were produced using different compositions as follows (in wt.%): (85TeO2-15ZnO, 85.00TeO2-12.95ZnO-2.05Al2O3, 85.40TeO2–3.20PbO-6.97ZnO-4.43Na2O, 83.5TeO2-16.5BaO, 82.77TeO2–17.23Nb2O5, 54.6TeO2-22.6WO3-22.8Bi2O3). The acquired mass attenuation coefficients (μ/ρ) were used to determine another vital parameters for gamma-ray shielding performance namely mean free path (MFP), half value layer (HVL), tenth value layer (TVL), energy absorption buildup factor (EABF), exposure buildup factor (EBF), effective atomic number (Zeff), respectively. Simultaneously, effective removal cross section (∑R) values for fast neutrons, proton projected range (PPR), alpha projected range (APR), proton mass stopping power (PMSP), alpha mass stopping power (AMSP), neutron absorption parameters (absorption neutron scattering cross section (σabs)), SAFE factors and relative dose distribution (RDD) have been investigated for fabricated glass samples. The results showed that the 54.6TeO2-22.6WO3-22.8Bi2O3 composition has the best performance in terms of nuclear shielding purposes. It is worth recommending the continuous investigations on chemical combinations and changes of TeO2 concentration for future applications.

Structural, mechanical and radiation shielding properties of newly developed tungsten lithium borate glasses: An experimental study

Abstract: The melt quench technique was used to fabricate the (25-x)Li2O-75B2O3-xWO3 (x = 1, 3, 5 and 7.5 mol%). The mass attenuation coefficients (μm) of the studied glasses were obtained by using the Gamma (γ) rays spectrometer (CANBERRA photo multiplier tube base model 802) which includes a detector (3 × 3 in.) NaI(Tl) crystal and the multichannel analyzer. The measured values have been compared with XCOM program at selected photon energies. Geometric progression (G–P) fitting method has been used to calculate the exposure build-up factor (EBF) and energy absorption build-up factor (EABF) in the energy range of 0.015–15 MeV. Moreover, EBF and EABF values have been applied to compute the specific fraction of absorbed energy (Sfae) and relative dose distribution (Rdd). The pulse-echo technique has been used to measure the elastic moduli for glass samples. The TBL4 glass sample shows the highest μm, effective atomic number (Zeff) and Young moduli values and lowest half value layer (HVL), mean free path (MFP), EBF, EABF, Sfae and Rdd values. The results of this investigations revealed that the fabricated TBL4 glass sample could be potentially utilized as an efficient and desirable kind of glass material as gamma shield to reduce the deleterious effects of radiation.

Bi2O3 effect on physical, optical, structural and radiation safety characteristics of B2O3[sbnd]Na2O-ZnO[sbnd]CaO glass system

Abstract: Novel transparent glasses with nominal composition of 50B2O3 +15Na2O+15ZnO+(20−x)CaO+xBi2O3; x = 0, 5, 10, 15, and 20 were synthesized using melt quenching method. The molar volume and density of the produced glasses with boosting the substitution ratio of Bi2O3 were measured. X-ray diffraction (XRD) patterns of the glasses were obtained for confirming their amorphous structure. UV–Vis spectra of the prepared samples were detected over the range of 190–1100 nm. By using UV–Vis results, Fermi level energy (Ef), refractive index (n), optical energy gap (Eg), Urbach's energy (Eu), and optical dispersion parameters were estimated. Results exposed that the optical energy gap (Eg) and single-oscillator energy (Eo) were decreased however other parameters increased with increasing Bi2O3 content. Mass attenuation coefficient (μ/ρ), as an essential variable for photon protecting research, was attained at 0.015–15 MeV photon energies for investigated glasses. Other relevant variables that can define the photon protecting features like Mean Free Path (MFP), Half Value Layer (HVL), equivalent atomic number (Zeq), gamma-ray exposure buildup factor (EBF), energy-absorption buildup factor (EABF) were obtained for the prepared glasses. The corollaries revealed that the BCNZB20.0 glass can be a strong shield material against gamma radiation. Finally, the proficiency of proposed glasses to stop fast neutrons charged alpha and proton particles was explored utilizing effective removal cross section (ΣR) and Mass Stopping Power (MSP) parameters. The glass with 20% Bi2O3 (BCNZB20.0) addition is very effective in preventing charged and uncharged particles. The addition of Bi2O3 to the studied glass system not only improved the optical and structural features but also the nuclear radiation shielding properties.

Optical and nuclear radiation shielding properties of zinc borate glasses doped with lanthanum oxide

Abstract: In this study, structure, optical and nuclear radiation shielding behaviors of (50-x)B2O3-30PbO-20ZnO-xLa2O3, (x = 0, 1.5, 3, 4.5, and 6) wt% glasses with various La2O3 concentrations were measured for their nuclear radiation shielding applications. Moreover, UV–visible absorption spectrum and the glass optical parameters were measured. The band gaps of optical energy for direct transition decreased from 3.90 eV for BPZLa1 glass sample to 2.78 eV for BPZLa5 glass, while it decreased from 2.58 eV to 1.83 eV glass for the indirect transition. The mass attenuation coefficient (μm) was experimentally measured using the HPGe spectrometer. The experimental results of shielding parameters were compared with values obtained using the XCOM program and FLUKA simulation code. The nuclear radiation shielding properties such as μm, HVL, Zeff, EBF and EABF were calculated for all glasses with various La2O3 concentrations. The results showed that μm and Zeff increased as the La2O3 concentration increased. The BPZLa5 glass sample had the minimum HVL, EBF and EABF. The BPZLa5 sample had the largest μm, Zeff.

Structural, elastic, optical and γ-ray shielding behavior of Dy3+ ions doped heavy metal incorporated borate glasses

Abstract: The effect of modifier ions in different basis have been analyzed through a new series of heavy metals incorporated borate based glasses 39H3BO3+30PbO+20MO+10Bi2O3 +1Dy2O3 (where M=Ca,Sr,Ba,Na and K) which are synthesized following melt quenching technique for radiation screening applications. The potentiality of glasses to withstand the penetration of fast moving neutrons is checked by various studies. Functional groups are identified through different stretching and bending modes of vibrations within the glass membrane through FTIR spectral analysis. In addition to that, other structural properties like Boron-Boron distance (dB−B), molar volume of oxygen (Vo), Oxygen Packing Density (OPD), optical basicity (Λth) and Bond density (nb) are calculated theoretically. The bonding nature (β) and nephelauxetic ratio (δ) values reveals that the glasses possess more of ionic linkages. The high density value exhibited by the Bismuth lead borate glasses indicates their capability to act as a good shielding material in reactors emitting hazardous radiation. Different moduli of elasticity (E, K, G, σ) values for the present glasses are calculated and the results reveal the enhancement in shielding performances when compared to other existing glasses and a comparative study is made on it. Optical studies are carried out and the absorption of Dy3+ions to different energy levels is observed and optical band gap (Eopt) values of the synthesized glasses are calculated along with the Urbach energy (ΔE) values. Radiation shielding properties of the produced glasses were investigated in terms of the mass attenuation coefficients (µm), transmission fraction (T), half value layer (HVL) and effective atomic number (Zeff) parameters. The results attained in the shielding study indicated that glass specimen with M = Ba exhibits enhanced shielding behavior as Ba owns high atomic number (Z) compared to other elements. Glass specimen with M = Na shows the poorest shielding characteristics due to the low Z of Na.

Machine learning on density and elastic property of oxide glasses driven by large dataset

Abstract: We conduct a comprehensive machine learning study on predicting the oxide glasses density, Young's modulus, shear modulus, and Poisson's ratio given compositions, by leveraging the large dataset collected at Corning Incorporated. The density and elastic property datasets have the size of 24,858 and 8519, respectively. Our results show that random forest, K-Nearest neighbor, and neural networks consistently deliver good performance, while support vector machine consistently underperforms. Lasso linear regression works best for density prediction, while Poisson's ratio is extremely challenging to predict with the best R2 score achieved to be around 0.7 by random forest. Additionally, feature importance analysis shows that La2O3 and BaO are the top two features for density prediction, while Na2O and B2O3 for Young's modulus and shear modulus prediction, and CaO and SiO2 for Poisson's ratio prediction. The study could be potentially leveraged as the baseline by future studies given the large dataset we trained on.

Radiation shielding, structural, physical, and optical properties for a series of borosilicate glass

Abstract: The current study explores the effect of BaO content on the shielding, optical, structural, and physical features of 10TiO2–10SiO2-(80-x)B2O3-xBaO (10 ≤ x ≤ 30) glass samples for their ability to be used as radiation shielding substances. X-ray diffraction spectra affirmed the amorphous state for all prepared samples. A series of physical parameters confirm the stability of the prepared glasses. The optical properties confirm the forming of non-bridging oxygens and these results are in line with the physical and structural properties and FTIR results. Regarding the shielding properties, the mass attenuation coefficient was measured experimentally and compared with the compatible values obtained from the XCOM program. Furthermore, other photon shielding properties, such as radiation protection efficiency, mean free path, exposure buildup factor, and energy absorption buildup factor, were calculated within the energy range of 15 keV-15 MeV. It was determined that this glass composition is suitable for photon radiation shielding applications.

Physical, structural, optical, and radiation shielding properties of B2O3- 20Bi2O3- 20Na2O2- Sb2O3 glasses: Role of Sb2O3

Abstract: This paper focuses on the role of antimony oxide (up to 15 wt%) in the physical, structural, optical, and radiation attenuating characteristics of boro-bismuth glasses within B2O3-20Bi2O3- 20Na2O2- Sb2O3 system. This glass system was prepared by melting at 1250°C and quenching into water. The physical properties were studied by measuring the density, molar volume, and x-ray diffraction for the prepared glass system. The structural features were investigated by determining packing density, passion ratio, oxygen packing density, and oxygen molar volume. The optical attributes were explored by evaluating bandgap, Urbach energy, refractive index, and other related parameters such as dielectric constant, reflection loss, molar polarizability, molar refractivity, optical dielectric constant, optical electronegativity, electron polarizability, optical basicity, metallization, and cut-off wavelength. On the other hand, the shielding properties of the prepared glasses were studied against different types of radiation such as gamma, electron, proton, and neutron beams. The radiation studies were carried out by utilizing Geant4 simulations and the newly developed Phy-X/PSD program. The radiation-shielding characteristics of the present samples were examined in terms of mass attenuation coefficient, stopping power, half value layer, removal cross section, mean free path, and effective atomic number of gamma, electron, and proton beams. The results showed that antimony oxide content had an important influence on the shielding ability against all of the types of radiations. Additionally, the obtained results were compared with those of standard radiation shields. It can be concluded that the present glasses have a promising future to be used as radiation shielding material, wherein the antimony oxide concentration can be balanced according to the desired application.

The role of CuCl2 in tuning the physical, structural and optical properties of some Al2O3–B2O3 glasses

Abstract: To study the effects of copper cations on some properties of a glass system, new glass formulation [75% B2O3 – 5% Al2 O3 – (20 - x) % Na2O – (x) % CuCl2], where x = 0.0, 1.0, 2.0, 3.5 and 4.5 mol.% was obtained via melt quenching method. X-Ray Diffraction (XRD) results emphasize the samples amorphous nature. The glasses internal structure was scrutinized via Fourier Transform Infrared Spectroscopy (FTIR). The dependence of density (⍴), boron to boron separation (dB-B), molar volume (Vm), optical absorbance (A), transmission (T), Urbach energy (EU), refractive index (n) and metallization criterion (M) on CuCl2 content was scrutinized. The trend of density (⍴), boron-boron separation (dB-B), molar volume (Vm), optical absorbance (A), Urbach energy (EU) and refractive index (n) show increasing behavior, while band gap (Eg) and metallization criterion (M) show decrement behavior with CuCl2 content. According to the obtained results (e.g. absorbance), these samples are probable candidates for some optical applications.

Physical, structural, optical and gamma radiation attenuation properties of germanate-tellurite glasses for shielding applications

Abstract: Germanate-tellurite glasses with a composition of (75-x) TeO2-xGeO2–125ZnO-125BaO, where x = 0, 5, 10, and 20 mol%, were synthesized A traditional melt-quenching-annealing process was used to fabricate these glasses, at 1000 °C for melting and 300 °C for five hours for annealing X-ray diffraction was used to investigate the structural features of each sample between 10 °C and 80 °C to prove the amorphous nature of these glasses Moreover, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) was employed to explore the functional groups of Te, Ge, and other elements To study the transparency, cut-off wavelength, and other optical properties of the glasses, such as indirect, direct, and Urbach energy band gaps, optical absorption was measured in the range of 200–800 nm Additionally, the radiation shielding properties for the germanium based-tellurite glasses were calculated using Monte Carlo N particle transport code (MCNP-5) The simulated results were compared with XCOM software and the results between the two methods closely agreed The maximum mass attenuation coefficient varied between 47305 and 50620 cm2g − 1 for TG1 and TG4 glasses respectively at 0015 MeV The effective atomic number (Zeff) for the prepared germanium based-tellurite glasses was evaluated and the results revealed that the maximum Zeff values were found at 004 MeV, varying between 4824 and 4998 for TG4 and TG1

The impact of barium oxide on physical, structural, optical, and shielding features of sodium zinc borate glass

Abstract: The study illustrates the impact of barium oxide (BaO) on structural, physical, optical, and radiation shielding features of a series of multi-component of barium-containing borate-based glasses, namely Sodium Zinc Borate Glass. The amorphous nature of each glass material was confirmed by X-ray diffraction (XRD) analysis. Fourier-Transform-Infrared (FTIR) was used to identify the BO3-BO4 distribution and how the variation of Ba-concentrations affects this distribution. The results show that the increase of barium content increases the density of glasses and, in turn, reduces their bandgap. The investigation of the shielding properties at different energies (0.01–10 MeV) by Phy-X program indicates that the high-density of Ba-30 exhibited the best performance in terms of attenuation factor. On the other hand, the samples Ba-0 and Ba-15 show the highest durability results (lowest dissolving rate). These outcomes indicate that the glass samples exhibited promising radiation shielding properties for different applications.

Germanate oxide impacts on the optical and gamma radiation shielding properties of TeO2-ZnO-Li2O glass system

Abstract: In this work, a series of tellurite glass combined with various concentrations of germanium oxide was fabricated according to the formula of (70-x)TeO2-xGeO2–20ZnO-10Li2O where x = 5, 10, 15 and 20 mol% via utilizing the melt-quench method for possible use in a radiation shielding applications. X-ray diffraction and Attenuated Total Reflectance Fourier Transform Infrared was employed to investigate the structure of the synthesized glasses. The density and Poisson's ratio for current samples reduced gradually from 5.221–5.008 g.cm−3 and 0.134–0.131, respectively, while the enhancement in bandgap values from 3.700–3.872 eV with addition of GeO2 is observed. The linear attenuation coefficient values at 0.015 MeV are 230.123 and 236.832 cm−1 for samples TG1 and TG4, respectively. Moreover, the lowest half-value layer attained via TG1 and raises from 0.0030 to 3.6684 cm while the highest HVL attained by TG4 and raises from 0.0029 to 3.9696 cm.

Effect of MgO and BaO on viscosity and structure of blast furnace slag

Abstract: The viscosity was measured by the cylinder method to investigate the effect of MgO and BaO on the viscous behavior of CaO-SiO2-Al2O3-MgO-BaO slags (CaO/SiO2 = 1.05, 7–10 wt%MgO, 0–3.5 wt%BaO). Based on the experimental data, the free running temperature and the activation energy were calculated to analyze the changes of characteristic of viscosity flow. The Fourier transformation infrared (FTIR) and Raman spectra were used to provide the information about the variation of slag structure. The results indicate that the viscosity, free running temperature, as well as activation energy decrease with the increase of MgO content in range of 7 wt%–10 wt%, and increase at BaO content from 0 wt% to 3.5 wt%. MgO provides free oxygen (O2−) to reduce the polymerization degree of slag and decreases the viscosity. However, the addition of BaO tends to form complicated structure and increase the viscosity. When BaO is added into slag, Ba2+ and O2− simultaneously influence the slag structure. O2− can break the Si-O bonds, and thus decrease the polymerization degree of slag. On the other hand, the charge compensation of Ba2+ can form complex aluminate-silicate structure and increase the viscosity of the slag. And the strong charge compensation effect that BaO acted is more dominated in the changes of slag structure.

Effect of Ge-addition on physical and optical properties of chalcogenide Pb10Se90-xGex bulk glasses and thin films

Abstract: Several substantial physical and optical properties of non-crystalline Pb10Se90-xGex bulk glasses and thin-films (0.0 ≤ x ≤ 10 at.%) have been studied. Bulk and film samples were synthesized via melt-quench and thermal-evaporation processes, respectively. The films were fabricated on pre-cleaned glass substrates under vacuum ≈5 × 10−4 Pa. The non-crystallinity of studied samples has investigated by X-ray diffractograms. A good-matching between selected compositional elements and those measured experimentally was confirmed by energy-dispersive X-ray analysis. The absorption nature of samples was studied in detail, where absorbance, absorption coefficient, skin depth and skin effect were discussed. The indirect transition bandgap energy was studied and its value decreases as Ge-content increases. Cohesive energy, average coordinate number, average atomization heat, lone-pair electrons, mean-bond energy, and others were discussed. Based on density values, many parameters were estimated and studied, like compactness, packing density, atomic densities, polaron radius, field strength. All studied characterizations are strongly dependent upon Ge-percentages.

Optical, structural and nuclear radiation security properties of newly fabricated V2O5-SrO-PbO glass system

Abstract: In this work, strontium vanadate glasses with the nominal composition (V2O5)60+ (SrO)40-x+(PbO)x (where, x = 0, 5, 10, 20, 30 and 40) were fabricated and their optical, structural, physical and nuclear radiation shielding qualities were examined. Amorphous structures of the vanadate glasses were demonstrated by XRD analysis. With the insertion of PbO into the glasses, the density of the glasses was raised from 3.455 to 4.581 g/cm3, while molar volumes were reduced from 43.57 to 43.27 cm3/mol. It was found that as the addition of PbO is enhanced, the optical band gap energy is declined in the range of 3.96–3.55 eV. The UV- absorption spectra of the strontium vanadate glasses containing PbO were recorded in the wavelength range 200–1100 nm. The refractive indices of the VSP glasses proved that the proposed glass system can be considered as promising materials for photoelectronic and optical filter devices. Finally, nuclear radiation shielding attributes of strontium vanadate glasses with lead oxide additive were determined for gamma photons and fast neutrons. The mass attenuation coefficients (μ/ρ) were obtained working WinXCOM data. With PbO content progressive rising from 0 to 40 wt%, the μ/ρ values were increased. Then other related parameters such as HVL, Zeq, EABF and EBF for gamma-ray shielding were found. With PbO added content instead of SrO, the Zeq values increased while HVL, EBF, and EABF values reduced. In addition, since the addition of PbO was enhanced the density, the capacity of VSP glasses to retain fast neutrons was also increased.

Newly developed Zinc-Tellurite glass system: An experimental investigation on impact of Ta2O5 on nuclear radiation shielding ability

Abstract: In this paper, the nuclear shielding properties of newly fabricated Zinc-Tellurite glasses doped with Ta2O5 with a composition (25ZnO.75TeO2)100-x.(Ta2O5)x (x=0, 1, 2, 3 mol%) were studied. Ta2O5 doped Zinc-Tellurite glasses prepared by the traditional melt quenching method. The mass attenuation coefficients were achieved for prepared glasses at 0.081-0.383 MeV photon energies employing experimental transmission measurements, which were performed with 3 Ci Ba-133 point source and Ultra Ge detector. The experimental results were compared with simulated MCNPX and theoretical WinXCOM data. Moreover, another important nuclear shielding parameters such as mass attenuation coefficient, half value layer, effective atomic number, effective electron density, equivalent atomic numbers, alpha and proton projected ranges, mass stopping power in the protection of gamma, neutron, alpha and proton radiation were calculated. In addition, buildup factors of investigated glasses were determined by using the G-P fitting method. Moreover, effective removal cross section ΣR and transition factors were determined. According to the results, the addition of Ta2O5 to the glass samples has a positive effect on the performance of nuclear shielding effects of the glass samples. It can be concluded that ZTT3 glass sample with the highest Ta2O5 contribution has excellent nuclear radiation shielding ability among the other fabricated glass samples.

Evaluation of photon, neutron, and charged particle shielding competences of TeO2-B2O3-Bi2O3-TiO2 glasses

Abstract: In this study, photon, neutron and charged particle shielding competences of five different glass systems which have the common chemical composition TeO2-B2O3-Bi2O3-TiO2 and contain different mole ratios of TeO2 in each sample were studied comprehensively. The fundamental photon shielding parameters, mass attenuation coefficient (µ/ρ), half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), and electron density (Neff) were evaluated in the range of 0.015–20 MeV. The µ/ρ values of all investigated glasses were simulated by using Geant4 Monte Carlo simulation code. Besides, the simulation work was supported utilizing the web version of XCOM code and the outcomes from two methods were compared. A good agreement between two methods was observed. Results reveal that µ/ρ, MFP, HVL, Zeff and Neff parameters of the investigated glasses strongly depend on photon energy and chemical composition. Also, the energy absorption buildup factors (EABF) and exposure buildup factors (EBF) of the proposed glasses were calculated via G-P fitting parameters for photon energies in between 0.15 and 15 MeV. Results show that the greatest values of buildup factors take place at higher energies for all glasses. Finally, calculation of the fast neutron removal cross section (ΣR) values of the glasses were performed. According to our calculations, ΣR values vary between 0.1169 cm−1 for TBBT30 sample with TeO2 = 30 mol% (ρ = 6.39 g/cm3) and 0.1048 cm−1 for TBBT88 sample with TeO2 = 88 mol% (ρ = 5.39 g/cm3). Consequently, it can be said that the TBBT30 glass seems to be the most promising shield to be utilized for both gamma and neutron shielding implementations among investigated TBBT glasses.

Dry sliding wear behaviors of Fe-based amorphous metallic coating synthesized by D-gun spray

Abstract: The Fe-based amorphous coating has been successfully deposited on a 9Ni steel substrate by d -gun spray. The microstructure and wear behaviors of the coating were studied in detail under dry sliding condition in a ball-on-disk mode by using Si3N4 ball as the counterpart. The results show that the Fe-based amorphous coating has a substantially complete amorphous structure, and the thickness, porosity, and surface hardness are 200 ± 30 µm, and 822 ± 10 Hv0.1, respectively. Therefore, the coating presented pretty good wear-resistant properties under dry sliding wear conditions with wear rates of (2.74~16.30) × 10−6 mm3N−1m−1. Besides, the results show that the wear rate of coatings is more sensitive to the applied sliding speed than the normal load. As the sliding speed changes from low (0.1 m s − 1) to high (1.0 m s − 1), the wear mechanism of the present Fe-based amorphous coating changes from oxidative wear to delamination wear.

TeO2-Ga2O3-ZnO ternary tellurite glass doped with Tm3+ and Ho3+ for 2 µm fiber lasers

Abstract: The glass-forming region of TeO2-Ga2O3-ZnO (TGZ) ternary tellurite glass was predicted via a thermodynamic method and then confirmed by a few experiments. Upon cooling the melts at a rate of ~20 K/s, the glass formation was observed within the range of 60–97 TeO2, 0–20 Ga2O3, and 0–40 ZnO (in mol%). For a better understanding of their fundamental physical, thermal and optical properties, the density, characteristic temperatures, Abbe number, linear and nonlinear refractive indices were comprehensively investigated. The possibility of TGZ glass host for 2 µm fiber lasers was studied through Tm3+ and Ho3+ doping and rare-earth sensitization. The results show such newly developed TGZ glass owns high thermal stability, low phonon energy and efficient 2 µm fluorescence, which enriches the tellurite glass system and may contribute to the research of high gain fiber lasers.

Glass formation, production and superior properties of Zr-based thin film metallic glasses (TFMGs): A status review

Abstract: Regarding the metallic glasses, the analysis of their unique structural, thermal and mechanical properties in the form of thin films metallic glasses (TFMGs) indicates a new class of materials with superior properties. These characteristics made TFMGs indispensable and promising in many areas. Recently, Zr-based TFMGs have particularly attracted the attention with their good mechanical and fatigue properties, corrosion resistance and thermal stability. In this review, we briefly talked about bulk and thin film forms of metallic glasses and reviewed recent significant and interesting results about TFMG with Zr content. In the last part of the study, the production and advantages of Zr-based bulk and thin film metallic glasses were discussed.

Physical, structural and optical properties of bio-silica borotellurite glass system doped with samarium oxide nanoparticles

Abstract: Glasses with chemical composition {[(TeO₂)0.7 (B₂O₃)0.3]0.8 [SiO₂]0.2}1-x {Sm₂O₃ NPs}x where x = 0.01 to 0.05 molar fraction have been fabricated using conventional melt-quenching method. Fourier transform infrared (FTIR) spectra reveal the presence of TeO3, SiO2 and BO3 structural units in the glass network. The existence of samarium oxide nanoparticles was recorded through high resolution transmission electron microscopy (HR-TEM) with particle size of 71.74 nm. Meanwhile, the optical properties of fabricated samples were determined by UV–vis analysis. The variation in the optical band gap identifies the modification in the glass network to the formation of bridging oxygen (BO) and non-bridging oxygen (NBO). Other optical parameter including refractive index, Urbach energy, electronic polarizability, oxide ion polarizability and optical basicity were determined. The metallization criterion values obtained is in the range of 0.403 to 0.409, which suggest that the glass material has a huge potential applications, in non-linear optics fields.

Synthesis, structural, optical and radiation shielding features of tungsten trioxides doped borate glasses using Monte Carlo simulation and phy-X program

Abstract: A novel glass system consists of six glasses was fabricated using melt quenching process according the chemical formula (60-x) B2O3+20Na2O2+20Bi2O3 +xWO3: x = 0, 1, 2, 3, 4 and 5 wt%. Archimedes method was used to determine the density and molar volume of the fabricated glasses. Moreover, the X-ray diffraction technique was used to show the variation of the amorphous phase with the addition of WO3 contents for the fabricated glasses. The optical features such as the refractive index (n), energy gap (Eg), distribution energy (Ed) and oscillation energy (Eo) were calculated based on the absorbance obtained from the UV-visible spectrum. The electromagnetic radiation (gamma ray) shielding capacity was evaluated using Monte Carlo simulation (MCNP 5) code in addition to Phy-X program. The results showed that the highest linear attenuation coefficient (LAC) occurred at 0.015 MeV and increased from 99.532 to 138.656 cm−1 for glasses coded as W 1 and W 6 respectively. The obtained results showed an enhancement of gamma ray shielding capacity with the addition of WO3 (wt%) to the fabricated glasses. Based on the estimated LAC, other shielding properties were calculated such as the glass half value layer (HVL), mean free path (MFP) and effective atomic number (Zeff). Finally, the ability of the fabricated glasses to resist the charged particles (alpha and proton) and uncharged neutrons were also estimated using SRIM program and theoretical calculation. The obtained results refer that the insertion of WO3 contents improves the shielding capacity for alpha and protons while it reduces the effective removal cross section of the fabricated glasses.

Unravelling the effect of nano-heterogeneity on the viscosity of silicate melts: Implications for glass manufacturing and volcanic eruptions

Abstract: Traditionally depicted as homogeneous materials, manmade and volcanic glasses are often subjected to nanostructuration during demixing and crystallization of their parental melt While the controlled formation of nanocrystals has been exploited for decades in the industrial production of glass-ceramics to obtain materials with superior properties, nano-heterogeneities have been recently recognized in volcanic products erupted explosively Here, a multi-pronged approach is adopted to highlight how the emergence of nano-heterogeneities exerts a previously unexplored influence on the viscosity of multicomponent silicate melts Calorimetry and viscometry provide evidence of how the formation of TiO2- and FeO-bearing nanocrystals increases the effective viscosity of suspensions Raman spectroscopy and transmission electron microscopy allow the correlation between the increase in viscosity and the degree of sample modification This study has implications for glass and glass-ceramics manufacturing and for the development of better numerical models of volcanic eruptions, which are key for the operational assessment of volcanic risk