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To better understand the variations in physical, mechanical, and electrical properties, (Ge 2 S 8) 100-x Te x chalcogenide glasses have been synthesized. These glasses encompass a composition range of 0 ≤ x ≤ 12. The mechanical properties have been studied by determining the longitudinal (ν L) and transverse (ν T) ultrasonic velocities. A network structure evaluation with composition has been performed via parameters like coordination number (< N r >), crosslinking density (D CL), glass transition temperature (T g), etc. Also, the elastic parameters trend values have been associated with the decrease in the cohesive energy value of the system. An overall physical analysis of the Ge-S-Te systems reveals that the system's rigidity and the cross-linking density are decreasing. Within the temperature range of 300–420 K, the temperature dependency of the dark conductivity and photoconductivity has been investigated. The intensity-dependent photoconductivity is governed by a power law, with intensity (I ph = G δ ) with δ lying between 0.5 and 1. The photosensitivity values reveal that the glassy system may be suitable for applications in optoelectronic devices. A correlation among the parameters has been established by calculating elastic parameters and conductivity measurements and evaluating the network structure theoretically. The present efforts clarify the composition-structure dependence and relationship in the Ge-S-Te glass series. [ABSTRACT FROM AUTHOR]

A series of mixed alkali-zinc borosilicate glasses with various r values (r = molar ratio of [ZnO] / ([R2O]+[ZnO])) from 0.00 to 1.00 were fabricated to probe the mixed alkali-zinc effects on thermo-mechanical properties. The nonlinear evolution of glass transition temperature (Tg) with the addition of ZnO is ascribed to the competition of two converse factors, i e, the Tg depression as one of the colligative properties for a solution, on the one hand, and the enhancement of Tg due to the higher field strength of zinc cations compared to that of alkali ions. However, the nonlinear evolution of elastic moduli and coefficients of thermal expansion with r is attributed to the variance of intermediate-range clusters, which is confirmed by infrared and Raman scattering spectra. These findings are very helpful in tailoring the performance of borosilicate glasses. [ABSTRACT FROM AUTHOR]

Abstract Wellbore stability analysis is a critical component of petroleum engineering, evaluating the risks of sanding, reservoir compaction, and casing failures. Laboratory rock mechanical measurements must be scaled up to reservoir scales to achieve accurate results. One challenge lies in upscaling dynamic measurements from petrophysical logs to pseudo-static elastic properties, which has significant implications for oil and gas operations. We present a novel approach that combines laboratory rock mechanical measurements with well-log data to develop a mechanical earth model (MEM) for an Iranian oilfield with over 350 wells. We conducted static elastic property measurements on 40 core samples from various layers and depths of carbonate and sandstone rocks, demonstrating the practical application of our approach. By integrating these measurements with dynamic log data and static-dynamic correlations, we established a framework for evaluating the mechanical properties of different layers. Our findings indicate that the safe mud weight window ranges from 41.5 to 118.59 pcf, while the stable mud weight window ranges from 41.5 to 156 pcf. We demonstrate the importance of conducting parallel rock mechanical studies on cores and logs to reduce uncertainties, costs, and risks during oil and gas operations. We also propose a novel methodology combining lithological characteristics, abnormally high pressure, and borehole instability mechanisms to evaluate the stability of borehole walls. This framework provides a fresh perspective on wellbore stability analysis and offers practical solutions for the industry. Essential novel techniques include developing a geomechanical model that integrates laboratory rock mechanical measurements with well-log data to evaluate mechanical properties and calculate safe and stable mud-weight windows. Our study advances wellbore stability analysis by providing a new method for addressing this long-standing challenge. It offers valuable insights for petroleum engineers working in the oil and gas industry.

To decipher the effects of replacing alkali with zinc on thermo-mechanical properties, a series of borosilicate glasses with the molar compositions of 70.65SiO 2 ·21.09B 2 O 3 ·1.88Al 2 O 3 ·1Li 2 O·(5.38- x)R 2 O· x ZnO (x = 0, 0.34, 0.67, 1, 1.34, 2.69, 4.04, and 5.38) were prepared. Upon adding a slight quantity of ZnO, a local extreme point for glass transition temperature (T g) appears. This behavior is deciphered to be originated from two opposite factors. On one hand, T g reduces as a characteristic of the colligative properties for a dilute solution; in addition, T g rises due to the higher field strength, bond energy and covalent characteristic of zinc cations compared to that of alkali ions. Otherwise, based on the evolution of intermediate-range clusters revealed by infrared, Raman and NMR spectra, we elucidate the atomic-scale structural origin, which leads to the nonlinear evolution of elastic moduli and coefficient of thermal expansion with the molar ratio of [ZnO]/([R 2 O]+[ZnO]). [ABSTRACT FROM AUTHOR]

In the composition range of x= 0-5 mol%, glasses in the system 60SiO2-35Pb3O4-(5-) ZnO-xMoO3 have been investigated. An amorphous network structure characterizes the glasses. The density values for the LZSM glasses scaled between 5.91 g/cm for Mo0 and 6.249 g/cm for Mo5. The ultrasonic technique indicates that the shear and longitudinal speeds (VT & VL) increase linearly as the amount of MoO3 substituted for ZnO in the fabricated glasses increases. The elastic moduli were calculated and found to be increased with an increase in both ultrasonic velocities and density of the glass, which suggests a correlation between these parameters in the fabricated glasses. The radiation attenuation capacity with the addition of MoO3 increased systematically, which indicates the role of MoO3 in modifying the glass composition and enhances its ability to attenuate against harmful radiation. Mo5 establishes excellent protective resources compared to other substances, so Mo5 develops a favorable selection for building radiation absorption blocks. Such blocks show an acute character in protecting both nature and a person's health versus the dangerous impacts of radiation exposure. [ABSTRACT FROM AUTHOR]

A comprehensive examination of the crystal structure, as well as elastic and thermal properties, of the recently created Zintl phase CsGaSb2 has been carried out using ab initio density functional theory pseudo-potential plane-wave calculations. All the provided facts presented are newly forecasted, with the exception of the structural properties under normal conditions. The calculated lattice parameters and interatomic bond lengths of the investigated material closely correspond to the actual values, indicating a high level of accuracy. Forecasts have been generated for the elastic parameters and related characteristics of both single-crystal and polycrystalline phases of CsGaSb2. The parameters encompassed in this list are elastic constants, shear modulus, bulk modulus, Poisson's ratio, Young's modulus, anisotropy indices, elastic wave velocities, Pugh's criterion, and Debye temperature. The mechanical and dynamic stability of CsGaSb2 as well as its elastic anisotropy have been established. The temperature dependence of various macroscopic properties, including bulk modulus, unit cell volume, volumetric thermal expansion coefficient, isochoric and isobaric thermal capacities, Debye temperature, Grüneisen parameter, and entropy function, was evaluated at specific pressures using Debye's quasi-harmonic approach in combination with ab initio calculations. [ABSTRACT FROM AUTHOR]

Deformcell is a python script designed to simplify and fasten routine procedure of preparing crystal structure files for calculating various mechanical properties in VASP program. The software allows users to prepare POSCAR files for calculations of different mechanical properties performing energy calculations of deformed crystallographic unit cells. It has been specially designed to allow users to automate unit cell deformation prior to energy calculations, making it useful both for scientific research and teaching computational chemistry applied to chemical materials sciences. [ABSTRACT FROM AUTHOR]

Wellbore stability analysis is a critical component of petroleum engineering, evaluating the risks of sanding, reservoir compaction, and casing failures. Laboratory rock mechanical measurements must be scaled up to reservoir scales to achieve accurate results. One challenge lies in upscaling dynamic measurements from petrophysical logs to pseudo-static elastic properties, which has significant implications for oil and gas operations. We present a novel approach that combines laboratory rock mechanical measurements with well-log data to develop a mechanical earth model (MEM) for an Iranian oilfield with over 350 wells. We conducted static elastic property measurements on 40 core samples from various layers and depths of carbonate and sandstone rocks, demonstrating the practical application of our approach. By integrating these measurements with dynamic log data and static-dynamic correlations, we established a framework for evaluating the mechanical properties of different layers. Our findings indicate that the safe mud weight window ranges from 41.5 to 118.59 pcf, while the stable mud weight window ranges from 41.5 to 156 pcf. We demonstrate the importance of conducting parallel rock mechanical studies on cores and logs to reduce uncertainties, costs, and risks during oil and gas operations. We also propose a novel methodology combining lithological characteristics, abnormally high pressure, and borehole instability mechanisms to evaluate the stability of borehole walls. This framework provides a fresh perspective on wellbore stability analysis and offers practical solutions for the industry. Essential novel techniques include developing a geomechanical model that integrates laboratory rock mechanical measurements with well-log data to evaluate mechanical properties and calculate safe and stable mud-weight windows. Our study advances wellbore stability analysis by providing a new method for addressing this long-standing challenge. It offers valuable insights for petroleum engineers working in the oil and gas industry. [ABSTRACT FROM AUTHOR]

Effects on mechanical and γ-ray shielding competence of TiO2-based glasses of chemical composition: 30PbO⋅4MoO3⋅(66 − z)B2O3⋅zTiO2 (0.0 < z < 2.0 mol%) was calculated in this report. The glass density was found to increase in the range of 4.650–4.696 g/cm3 concurrent with a decline in the oxygen molar volume (OMV) from 10.633 to10.547 cm3/mol when [Ti4+] molar fraction is increased in the glass samples. The Gibbs free energy was found to be between 20.874 and 22.586 kJ/cm3 and was found to be influenced by TiO2 concentration in these glasses and on the valance states of Ti3+ and Mo5+. The affinity of mass attenuation coefficient (MAC) values (0.039 < MAC < 6.198 g/cm3) in the examined photon energy domain 0.015 < E < 15.0 MeV has the following chronological sorting: MACT0 < MACT2 < MACT4 < MACT6 < MACT8 < MACT10 < MACT15 < MACT20. The half-value-layer (HVL) trend of Mo-glasses was balanced against two standard RS-glass systems and discovered to possess a less γ-ray shielding competence as RS-(360, 520) or concrete. Also, we found that when the [Ti3+]/[Mo5+] ratio exceeds 0.8 mol%, then both ions participate in the studied properties via de-polymerization of the glass network. These outcomes revealed that the safety effectiveness against radiation and physic-mechano-properties can be synchronized for diverse purposes. [ABSTRACT FROM AUTHOR]

This study uses density functional theory calculations to study the impact of pressure on the structural, elastic, and thermodynamic properties of CaRh2P2 and BaRh2P2 compounds. The equilibrium structural parameters closely match the experimental values. CaRh2P2 shows a greater reduction in lattice parameter "a" under pressure, while BaRh2P2 shows the opposite trend. The single-crystal elastic constants calculated for both compounds meet the criteria for mechanical stability under varying pressures up to 18 GPa. The study extends to polycrystalline elastic properties, including bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and related properties, under pressures up to 18 GPa. The Pugh ratio, Cauchy pressure, and Poisson's ratio indicate the ductile behavior of the title compounds. BaRh2P2 exhibits superconducting characteristics, unlike CaRh2P2, confirmed by interlayer PP bond length calculations. Debye's quasi-harmonic model explores the temperature dependencies of various properties, with results that align well with elastic constant data, thus validating the results. [ABSTRACT FROM AUTHOR]

The density, boron–boron separation, and molar volume of 4Al2O3–12Na2O-(18-x)SiO2-(64-x) B2O3-(2+2x)Bi2O3 (where x = 2, 4, 6 and 8 mol%) are increasing with the addition of Bi2O3. The addition of Bi2O3 results in an open network structure. The elastic moduli decrease from 34.711 to 29.875 GPa for Young modulus (E); 20.395 to 15.843 GPa for bulk modulus (B); from 15.257 to 13.494 GPa for shear modulus (G) and 40.738 to 33.836 GPa for longitudinal (L) respectively with increased Bi2O3 concentration. FTIR spectrainvestigation found BO3, BO4, SiO4, and BiO6 structural units to be present. The glasses' highest mass attenuation coefficient (MAC) is at 0.0395 MeV, the lowest energy value. It gradually decreases as energy increases. There is a decrease in the linear attenuation coefficient (LAC) values with energy. Sample Bi18 has the highest MAC and LAC values due to its high concentration of Bi2O3. Across the entire energy range, sample Bi18 has the highest effective atomic number, and the lowest half value layer and mean free path values across all energy values. The transmission factor (TF) values for Bi6 indicate that the required thickness for blocking 90% of the radiation must be greater than the thickness necessaryfor the attenuation of 50%. Bi18 has the lowest TF compared to other glass samples. The radiation protection efficiency values for Bi18 are highest, confirming their full protection ability. Bi18's is the best choice for radiation shielding.

The values of the shear v s and longitudinal v l wave velocities were calculated for 14 selected titanium oxynitrides TiN x O y using the known values of Young’s modulus and Debye temperature. The errors Δ of the calculations did not exceed ±0.01%. It turned out that some TiN x O y samples are able to compete with artificial diamonds in terms of v l values and can potentially be used in acoustic resonators for intelligent chemical and biochemical sensors. A number of elastic, thermodynamic and thermophysical quantities were calculated, and graphical dependencies between them were plotted. The established correlations were used to develop two algorithms for predicting the properties of TiN x O y alloys based on a single experimental parameter, namely the X-ray coefficient of thermal expansion or pycnometric density. The highest accuracy was shown by the method based on the experimental density, which allowed to estimate, with acceptable errors, the values of the shear v s and mean v m wave velocities (Δ = ±(1–5)%), the minimum thermal conductivity λ min within the framework of the Cahill‒Pohl model (Δ = ±(0–3)%), the isobaric C p and isochoric C V heat capacities (Δ < 1%); while the known experimental methods and alternative models for determining these quantities are characterized by wider error intervals: Δ(v s) = ±(1–10)%, Δ(λ) = ±(1–10)% and Δ(C p) = ±(1–3)%.

Determining the elastic constants for composites with fibers is a continuous concern of researchers, being studied and analyzed different types of materials, with different topologies and geometries. In the work, these constants are determined for a composite reinforced with cylindrical fibers with a rectangular packing. The obtained results are applied for the calculation of these constants for a composite used in engineering applications. [ABSTRACT FROM AUTHOR]

In recent years, tubular nanostructures have been related to immense advances in various fields of science and technology. Considerable research efforts have been centred on the theoretical prediction and manufacturing of non-carbon nanotubes (NTs), which meet modern requirements for the development of novel devices and systems. In this context, diatomic inorganic nanotubes formed by atoms of elements from the 13th group of the periodic table (B, Al, Ga, In, Tl) and nitrogen (N) have received much research attention. In this study, the elastic properties of single-walled boron nitride, aluminium nitride, gallium nitride, indium nitride, and thallium nitride nanotubes were assessed numerically using the nanoscale continuum modelling approach (also called molecular structural mechanics). The elastic properties (rigidities, surface Young's and shear moduli, and Poisson's ratio) of nitride nanotubes are discussed with respect to the bond length of the corresponding diatomic hexagonal lattice. The results obtained contribute to a better understanding of the mechanical response of nitride compound-based nanotubes, covering a broad range, from the well-studied boron nitride NTs to the hypothetical thallium nitride NTs. [ABSTRACT FROM AUTHOR]

This work deals with the fiber ends debonding-induced elastic moduli degradation of a short fiber reinforced composite (SFRC). The strain fields of the matrix in a representative volume element (RVE) of the SFRC are determined from an imaginary fiber technique. By using the debonding boundary conditions, the debonded modulus of the composite is derived, which is affected by not only the far-field but also the transient solutions for the longitudinal strain of the matrix. Particularly, the imaginary fiber technique provides unbounded solution for a moderately large fiber aspect ratio. This is resolved by separating the RVE along the fiber direction into two domains. Combining the longitudinal strains in both domains, the longitudinal modulus is determined, and the longitudinal bridging tensor element in the micromechanics Bridging Model is amended. Five elastic moduli of an SFRC after the fiber end debonding are obtained on the amended Bridging Model. The effects of the fiber volume fraction, fiber aspect ratio, and fiber-to-matrix modulus ratio on the end-debonded longitudinal modulus, transverse modulus, and longitudinal Poisson's ratio are investigated. [ABSTRACT FROM AUTHOR]

This work studies solutions to determine the macro-elastic moduli of three-phase composite materials with imperfect interfaces in 2D. Which is based on the coated circular assemblage model of Hashin-Strikman and the polarization approximation method (PA) to develop the formulae for elastic moduli of circle inclusions with spring-layer and surface-stress imperfect interfaces. From that, explicit algebraic expressions were obtained to estimate the elastic moduli of three-phase composites with imperfect interfaces, in which two phases are different with circular inclusions distributed randomly in the matrix. Besides, the FFT algorithm and the differential approximation (DA) are also developed to determine the elastic moduli of the three-phase composite with imperfect interfaces. The results of the FFT numerical methods will be compared with the DA and PA results with different material cases to show the effectiveness of the applied methods. [ABSTRACT FROM AUTHOR]

A new formulation of the bismuth-zinc-borate glass system has been fabricated using the conventional melt-quenching method. The amorphous phase of the glass sample has been confirmed by the nonexistent of any crystalline peak presented by X-ray diffraction patterns. The Fourier-transform infrared spectroscopy result displays several bands associated with the Zn–O and B–O–B bonding. The glass samples exhibited a density increase from 3.19 to 4.28 g/cm3 and the molar volume increased from 23.48 to 31.00 cm3/mol. The density of the glasses increases due to the addition of Bi2O3 which has a higher atomic mass compared to the other elements in glass compositions. The addition of Bi2O3 contributes more mass to the glass structure, leading to an increase in overall density. The incorporated Bi2O3 reduced the longitudinal (6134.41–5121.94 ms−1) and shear (3310.50–2848.15 ms−1) velocities. The elastic moduli resulted in a decreasing behavior when Bi2O3 concentration increased, and the values ranged from 120.04 to 112.21 GPa for longitudinal modulus, 34.96–34.69 GPa for shear modulus, 73.43–65.95 GPa for bulk modulus, and 90.52–88.56 GPa for Young's modulus. The Poisson's ratio presents the same trend as the modulus, while the microhardness shows an inversely proportional trend. The BiZnB4 sample demonstrates the lowest Poisson's ratio (0.276) and highest microhardness (5.18 GPa) values. These findings show that the physio-elastic properties are composition-dependent, suggesting potential applications as flexible glass panels for dynamic building glass design. [ABSTRACT FROM AUTHOR]

This study focuses on zinc-boro-soda-lime-silica (ZnO − B2O3 − SLS) glasses produced through fast-cooling melt-quenching. The influence of Eu3+ ions on glass properties is explored. As Eu3+ concentration rises, bulk density and molar volume increase from 3.423 to 3.484 g/cm3 and 21.760 to 23.768 cm3/mol, respectively. X-ray diffraction indicates amorphous phase dominance supported by glassy surface morphology. Ultrasonic measurements show the increasing and decreasing trend for ultrasonic velocities and elastic moduli with increasing Eu3+ concentration. Poisson's ratio of the samples signifies their low cross-link density behavior. Moreover, the ZBS-3Eu presents the highest microhardness value of 4.776 GPa. The sample's fractal bond connectivity varies from 1.814 to 2.051, suggesting a 2D structure. Likewise, the ZBS-3Eu glass sample exhibits the most rigidity attributed to its highest fg value of 0.075. These findings suggest that ZBS-3Eu has the potential for applications requiring high-strength glass. [ABSTRACT FROM AUTHOR]

The composition of the pentagonal glass system, which is composed of 57B2O3-16SiO2-11BeO- (16-x) MgO-xLa2O3, x = (0 ≤ x ≤ 16 mol %), has been synthesized by the melt quench process. XRD diffractograms' wide haloes testified to the materials' amorphous state. It was discovered that, density increased in response to La2O3 concentration, whereas molar volume decreased. Additionally, the ranges of longitudinal and shear velocities are 4730 to 5085 m/s and 2685–2895 m/s, respectively. The elastic moduli for longitudinal range between 71.9–154.3 GPa, shear range between 23.2–50 GPa, bulk range between 23.2–50 GPa, and Young's range between 58.5–126 GPa, respectively. The study employed Phy-X/PSD code to examine the radiation attenuation behaviour of magnesium beryllia-borosilicate, also known as (BMBSLa) glasses, at varying concentrations of La2O3. We examined the relationship among the half value layer (HVL) and density. HVL values at a density of 3.213 g/cm3 range from 0.0087 to 11.746 cm and at density of 5.967 g/cm3 range from 0.02 to 5.727 cm at (0.015–15 MeV). Tenth value layer (TVL) and mean free path (MFP) are evaluation and comparison between HVL, TVL and MFP for the same glass at specific energy were also conducted. The glass samples under investigation are excellent candidates for usage in the field of shielding radiation because they are more transparent. [ABSTRACT FROM AUTHOR]

The structural, physical, mechanical, and radiation shielding characteristics of the glass system consisting of 27SiO2-53B2O3- 2ZnF2- (18-x) Li2O-xV2O5 (0 ≤ x ≤ 2) were studied. The glasses were fabricated using the melt-quench method. It was found that the density and molar volume of the current glasses were influenced by the V2O5 content. The structural characteristics were investigated using X-ray diffraction (XRD). Using the pulse-echo method, longitudinal and shear velocities were measured to study elastic characteristics. The radiation shielding characteristics were determined using the Phy-X program for γ rays. The densities varied from 3090 kgm−3 to 4140 kgm−3, whereas molar volume varied from 19.6 × 10–6 m3 mol−1 to 15.36 × 10–6 m3 mol−1. With the addition of V2O5, ultrasonic velocities, elastic moduli (experimentally and theoretically), hardness (H), and Debye temperature ( θ D ) were increased. It is noteworthy that the theoretically predicted elastic moduli, obtained using the (MMM) model, exhibits a remarkable agreement with the experimentally determined elastic moduli. This consistency is further corroborated by the shielding properties of the borosilicate glasses. As the V2O5 content increases and the Li2O decreases, the MAC values increase suggesting greater radiation shielding capacities. It's observed that the MAC values for G5 are higher than those for G1. Therefore, it is a great choice for application in the field of radiation shielding. [ABSTRACT FROM AUTHOR]

In the present work, the density functional theory calculation has been performed for RbMgF 3-x H x with GGA-PBE approximation implemented in CASTEP code. First time the structural, mechanical, electronic and optical properties of perovskite RbMgF 3-x H x (x = 0, 0.3, 0.6, 0.9, 1.2, 1.5, 1.65, 1.80, 1.95, 2.25, 2.55, 2.85 and 3.0) has been investigated in details along with hydrogen storage applications. The results of formation enthalpy and elastic constants indicate that the materials are synthesizable. It has been found that the concentration of hydrogen storage decreases the elastic moduli and anisotropy whereas the bandgap becomes narrow because of the shifting of conduction band toward the fermi level. This indicates that hydrogen inclusion altered the electronic properties of the material and material can also be used in various optoelectronic devices alongwith hydrogen storage application. The crystal structure shifted from cubic to tetragonal during the hydrogen storage. The optical properties were thoroughly investigated between 0 and 10 eV. It has been found optical properties are enhanced with the doping concentration of hydrogen, which makes them good candidates for optoelectronic devices. The gravimetric ratio of hydrogen increased up to 2.61% with hydrogen incorporation. The presented material is an efficient material not only for opto-electronic applications but also for hydrogen storage as well. • Electronic and optical properties of H-doped RbMgF 3 are studied. • All studied materials are indirect band gap semiconductors. • Density of states were investigated with reduction of band gap from 6.263 to 2.124 eV. • The RbMgF 3-x H x is a good transmitter and shows good optical response in the visible region. • The gravimetric storage capacity (%) values are varied from 0.39 % to 2.61 %. [ABSTRACT FROM AUTHOR]

This study investigates the effects of increasing PbO concentration on the Al2O3–PbO–B2O3–SiO2 glasses' physical, mechanical and gamma ray shielding properties. PbO addition leads to higher density and molar mass, making the glass denser. However, molar volume decreases, indicating a more compact structure. Interatomic distances and ion concentration change, strengthening atomic interactions. Oxygen molar volume increases, but packing density drops with more PbO, impacting the glass lattice. Optical basicity rises, suggesting improved electron transport and optical behavior. Electronegativity decreases, and electronic polarizability increases with higher PbO content, rendering the glass more electron-donating and sensitive to external electric fields.This study investigates glass mechanical properties using the Makishima–Mackenzie model. As PbO concentration rises, elastic moduli consistently decrease, signifying increased flexibility in glass structures. The mass attenuation coefficients (MAC) of the chosen glasses were evaluated in the 0.284–1.333 MeV energy range. It was found that increased PbO content leads to a corresponding MAC enhancement. The MAC values at 0.284 MeV were 0.297 and 0.349 cm2/g, while at 0.511 MeV they varied between 0.124 and 0.135 cm2/g. It was found that Glass Pb47.5 sample, which contains a higher amount of PbO compared to the other glasses, had the highest MAC at all energies. The results showed that the PbO has a notable impact on the MAC and thus on the radiation attenuation performance at lower energy. Moreover, increased glass density led to a corresponding LAC increase, which at 0.284 MeV increased from 1.269 cm−1 for Pb32.5 to 1.898 cm−1 for Pb47.5. According to the LAC results, one simple means of enhancing the glasses' radiation shielding properties is utilizing a high PbO percentage. This paper aims to illuminate silicate glasses' radiation shielding abilities. The paper will investigate the efficiency under specific conditions, like high-energy radiation. Moreover, it will explore innovative methods to enhance their shielding competence, concreting the way for a better yet effective radiation shielding approach. [ABSTRACT FROM AUTHOR]

The application of pultruded glass fibre-reinforced polymer composites (PGFRPC) as a replacement material for conventional wooden cross-arm in high transmission towers is relatively new. Although there are several studies on enhancement of the cross-arm structure, there is still a lack of study on the elastic properties of a full-scale PGFRPC cross-arm enhanced with honeycomb sandwich structure. To full-fill the gap, this paper describes an experimental methodology used to obtain the elastic properties of the cross-arm using a three-point bending (3-PB) flexural test by following ASTM D790 standard for deflection behaviour and flexural creep response. The investigation involved several cross-arm members subjected to loading across different span lengths by propose two methods in order to measure the effective cross-arm member section flexural modulus (Ec) and shear modulus (Gc). The creep behaviour of the panels was successfully modeled using Findley's power law, confirming the ability of this empirical approach to simulate the viscoelastic response of the cross-arm. Next predictions were made for up to 50 years of service and the results shows the elastic modulus reduction for the enhanced cross-arm with the honeycomb sandwich structure was approximately reduce to 70 % compare with existing cross-arm which reduce almost 75 % at 50 years of application. The enhanced cross-arm exhibited lower deflection and better creep resistance and increased the bending strength of the cross-arm as well as extended its potential lifespan. Predictions indicated that the enhanced cross-arm maintained better mechanical properties over time compared to the existing one.

[Display omitted] For the first time, the elastic constants c 11 , c 12 , and c 44 of disordered cubic titanium monoxide TiO y were determined depending on the oxygen content y in the homogeneity region from TiO 0.80 to TiO 1.25. It has been established that the values of the elastic moduli depend on the oxygen content y and the crystallographic direction [ hkl ]. Large changes in the elastic characteristics of TiO y depending on the [ hkl ] direction indicate a strong anisotropy of the elasticity of disordered cubic titanium monoxide. [ABSTRACT FROM AUTHOR]

The pyrolite model, which can reproduce the upper-mantle seismic velocity and density profiles, was suggested to have significantly lower velocities and density than seismic models in the lower mantle transition zone (MTZ). This argument has been taken as mineral-physics evidence for a compositionally distinct lower MTZ. However, previous studies only estimated the pyrolite velocities and density along a one-dimension (1D) geotherm and never considered the effect of lateral temperature heterogeneity. Because the majorite-perovskite-akimotoite triple point is close to the normal mantle geotherm in the lower MTZ, the lateral low-temperature anomaly can result in the presence of a significant fraction of akimotoite in pyrolitic lower MTZ. In this study, we reported the elastic properties of Fe-bearing akimotoite based on first-principles calculations. Combining with literature data, we found that the seismic velocities and density of the pyrolite model can match well those in the lower MTZ when the lateral temperature heterogeneity is modeled by a Gaussian distribution with a standard deviation of ∼100 K and an average temperature of dozens of K higher than the triple point of MgSiO3. We suggest that a harzburgite-rich lower MTZ is not required and the whole mantle convection is expected to be more favorable globally.

Two-dimensional (2D) nanostructures of aluminum nitride (AlN) and gallium nitride (GaN), called nanosheets, have a graphene-like atomic arrangement and represent novel materials with important upcoming applications in the fields of flexible electronics, optoelectronics, and strain engineering, among others. Knowledge of their mechanical behavior is key to the correct design and enhanced functioning of advanced 2D devices and systems based on aluminum nitride and gallium nitride nanosheets. With this background, the surface Young's and shear moduli of AlN and GaN nanosheets over a wide range of aspect ratios were assessed using the nanoscale continuum model (NCM), also known as the molecular structural mechanics (MSM) approach. The NCM/MSM approach uses elastic beam elements to represent interatomic bonds and allows the elastic moduli of nanosheets to be evaluated in a simple way. The surface Young's and shear moduli calculated in the current study contribute to building a reference for the evaluation of the elastic moduli of AlN and GaN nanosheets using the theoretical method. The results show that an analytical methodology can be used to assess the Young's and shear moduli of aluminum nitride and gallium nitride nanosheets without the need for numerical simulation. An exploratory study was performed to adjust the input parameters of the numerical simulation, which led to good agreement with the results of elastic moduli available in the literature. The limitations of this method are also discussed. [ABSTRACT FROM AUTHOR]

This work examines a number of synthetic glasses with the molecular compositions 60B2O3, 5CaO, 5Bi2O3, and xEr2O3 (BBCEr-x, where x = 0.0–2.0 mol%) to determine their structural, optical, mechanical, physical, and γ-rays protective properties. Glass was shown to be in an amorphous state by XRD measurements. The density (ρ) of BBCEr-x grew from 3.14 to 3.32 g/cm3 when the molar addition of Er3+ ions increased from 0.0 to 2.0 mol%. The absorbance spectra of the BBCEr-x samples showed seven absorption bands related to the Er3 + electronic transitions (4f–4f). It has been evaluated the dependency of elastic moduli, including Poisson's ratio (σ), and the efficacy of shielding against incoming gamma rays on [Er2O3] mol%. The Makishima-Mackenzie theory was used to calculate the mechanical parameters. As a function of [Er2O3] mol%, the micro-hardness (H) of the Vickers increases while the ratio of the Passion decreases. The mass attenuation coefficient (MAC) has been calculated in the energy range of 0.015–15 MeV using the XCOM and Phys-X/PSD programs and has been compared with Monte Carlo simulations performed using the Geant4 code. The linear attenuation coefficient (LAC), transmission factor (TF), and fast neutron removal cross-sections (ΣR) all showed monotonic dependence on [Er2O3] mol%. With photon energies of 0.015–15 MeV, the sample BBCEr-0.0 had the lowest values of MAC, measuring 34.418–0.029 cm2/g. This result reflects the interaction between density and [Er2O3] impacts on the mechanical and radiation shielding capabilities of the synthesized glasses. The greatest MAC values were found in the BBCEr-2.0 sample, which ranged from 39.6 to 0.037 cm2/g. It was found that ΣR approximates the molar volume (Vm) and exhibits the same trending behavior. This study demonstrated that radiation shielding and mechanical properties could both be customized for indoor or outdoor scientific or industrial usage. [ABSTRACT FROM AUTHOR]

Abstract—The paper presents an attempt to estimate the contribution of thermal processes in the Earth's crust to earthquake generation. As a case study, the seismically active junction zone of the Chu depression and Kyrgyz ridge of the Northern Tien Shan is considered. The analysis is based on the previously constructed models of temperature, petrophysical characteristics, and elastic moduli. The silica content model derived from seismic tomography data is used to build a lithotype model. The thermal conductivity model is constructed and used in conjunction with the temperature model to create a depth model of the heat flow density. The shear stress and thermoelastic stress models derived from density, elastic moduli, and temperature models are compared with the distribution of earthquake hypocenters in the region. The comparison suggests that on the scale of the seismically active junction zone of the Chu depression and the Kyrgyz ridge of the Northern Tien Shan, seismicity is mainly determined by thermomechanical effect induced by hot ascending flow of acid magma rising from the upper mantle beneath the Muyunkum–Narat median massif. [ABSTRACT FROM AUTHOR]

Particle shape variability is a key to understanding the rich behavior of granular materials. Polyhedra are among the most common particle shapes due to their ubiquitous origins in nature such as rock fragmentation and mineral crystallisation. Because of their faceted shape, polyhedral particles tend to assemble in jammed structures in which face-face and face-edge contacts between particles control the packing-level properties. In this paper, we use tri-periodic particle dynamics simulations to derive for the first time a generic analytical expression of the elastic moduli of polyhedral and spherical particle packings subjected to triaxial compression as a function of two contact network variables: (1) a "constraint number" that accounts for the face-face and edge-face contacts between polyhedra and is reduced to the coordination number in the case of spherical particles, and (2) the contact orientation anisotropy induced by compression. This expression accurately predicts the simulated evolution of elastic moduli during compression, revealing thereby the origins of the higher elastic moduli of polyhedral particle packings. We show that particle shape affects the elastic moduli through its impact on the contact network and the level of nonaffine particle displacements is the same for the simulated shapes. Its nearly constant value during compression underlies the constant values of our model parameters. By connecting the elastic moduli to the contact network through parameters that depend on particle shape, our model makes it possible to extract both the connectivity and anisotropy of granular materials from the knowledge of particle shape and measurements of elastic moduli. [ABSTRACT FROM AUTHOR]

The torsion problem for a radially inhomogeneous transversely isotropic cylinder of small thickness was investigated by the method of asymptotic integration of elasticity theory equations. It is assumed that the side part of the cylinder is stress-free, and boundary conditions are set at the ends of the cylinder, leaving the cylinder in equilibrium. The elastic moduli are thought to be arbitrary continuous functions of the variable along the cylinder radius. The formulated boundary value problem is reduced to a spectral problem containing a small parameter characterizing the thin-walledness of the cylinder. Homogeneous solutions are built, i.e. any solutions of the equilibrium equation satisfying the condition of no stresses on the side surfaces. It is shown that the solution of the torsion problem consists of a penetrating solution and a boundary layer character solution similar to Saint-Venant’s edge effect in the theory of inhomogeneous plates. The penetrating solution determines the internal stress-strain state of a radially inhomogeneous cylinder. The stress state determined by the penetrating solution is equivalent to the torsional moments of stresses acting in the cross-section perpendicular to the cylinder axis. Solutions having the boundary layer character are localized at the ends of the cylinder and decrease exponentially with distance from the ends. These solutions are absent in applied shell theories. Asymptotic formulas for displacement and stresses are built, which make it possible to calculate the three-dimensional stress-strain state of a radially inhomogeneous transversely isotropic cylinder of small thickness. Based on the obtained asymptotic expansions, it is possible to assess the applicability of applied theories and build a refined applied theory for radially inhomogeneous cylindrical shells. [ABSTRACT FROM AUTHOR]

This work investigates the structural and elastic properties of x PbF 2 – 20 Bi 2 O 3 – 10 MoO 3 – (70-x) B 2 O 3 (where x = 0, 5, 10, 15, and 20 mol%) glasses with an emphasis on the effects of different PbF 2 concentrations. Amorphousness of the samples is confirmed by X-ray diffraction (XRD) inspection because no identifiable peaks are present. Changes in the connectivity and structure of the glass network can be detected by the observed 17 % increase in glass density from 4.1024 g/cm3 to 4.7956 g/cm3 as PbF 2 concentration increases. FTIR and Raman spectroscopy investigations revealed the increase of PbF 2 results in the creation of Pb 1 / 2 2 + [F-BO 4/2 ], [PbF9+] units and the conversion of BO 3 to BO 4 units. These structural changes are emphasised by the shift towards higher wavenumbers and the progressive widening of the bands from 1200 cm−1 to 1500 cm−1. The results show an increase in the proportion of N 4 with additional PbF 2 , which affects the elastic properties of the glass. The computed elastic moduli demonstrate that the increase in [PbF9+] structural units caused by PbF 2 addition causes polymerization in the molybdenum bismuth-borate network. The increasing rigidity of the glass network is further increased by the formation of highly coordinated [PbF9+] and by the increasing parameters of K MM and K BC. [ABSTRACT FROM AUTHOR]

The successful synthesis of the novel composition glass system with the empirical formula (9CdO + 11SiO2 + 64B2O3 +(2-x) LiF +(14+x) MoO3 for x = 0, 0.5, 1, 1.5, and 2 mole %) has been fabricated. The density increased from 2.87 to 3.25 g/cm3 while the molar volume decreased from 29.04 to 26.37 m3/mol. The longitudinal ( V l ) increase from 4740 to 4855 m/s and shear ( V t ) velocity increase from 2635 to 2745 m/s. Elastic moduli of the glass sample also exhibit an increasing behavior with greater MoO3 concentration. Studies comparing experimental and theoretical elastic moduli reveal the same behavior. The Phy-X/PSD database was utilized to calculate the radiation protection values. With the substitution of MoO3 for LiF, the fundamental radiation shielding and significant parameters ( M A C , L A C , Z eff , and ∑ R ) increase as G 5> G 4 > G 3 > G 2 > G 1. According to the results, the G 5 sample had the lowest HVL, TVL, and MFP of all the glasses, which can be ascribed to the sample's high density due to its high MoO3 content. According to this investigation, the G5 sample has the best radiation properties when photon energy is increased. [ABSTRACT FROM AUTHOR]

Role of V2O5 as a strong network glass modifier on the optical, elastic, physical, and radiation protection performance of V2O5-based glasses in form 10CaF2-(20-x)Bi2O3-60P2O5-10B2O3:xV2O5, x = 0.0, 0.5, 1.0, 1.2, 0.2, and 2.5 mol% was investigated in this article. The studied glasses have been synthesized using the melt-quenching technique. The investigated samples coded as V0, V1, V2, V3, V4, and V5 according to x values. Difference theoretical approaches have been utilized to achieve these goals including: radiation shielding calculations, optical, and elasto-mechanical properties. The optical basicity (Λ(Eg)) was found to decrease from 0.5630 to 0.5593 with increasing the mol% of [V4+] in the glass samples. The density was decreased from 4.134 to 3.817 g cm−3 associated with a simultaneous decrease in the oxygen molar volume (OMV) from 12.5 to 12.25 cm3/mol as the mol% of [V4+] increased in the samples. The Vicker's hardness was found to be diminished with increasing V2O5 content in the investigated glasses. All elastic moduli were reduced as V2O5 increased. Refractive index increased from 2.20 to 2.63, while metallization criterion decreased from 0.341 to 0252. The observed trend of mass attenuation coefficient (MAC) values in the tested energy spectrum followed the sequence: (MAC)v0 > (MAC)v1 > (MAC)v2 > (MAC)v3 > (MAC)v4 > (MAC)v5. Also, we found that linear attenuation coefficient (LAC) increased, while the half value layer (HVL), and transmission coefficient (TF%) were also decreased. The HVL values of the current samples were compared with standard glasses, and it found that V2O5-based samples possess a comparable photon protection capacity as commercial RS-360 and RS-520 glasses. [ABSTRACT FROM AUTHOR]

Condition assessment and maintenance of vast road networks is a challenge both technically and financially in many low and middle-income countries (LMICs). It often requires rapid data collection techniques, quick analysis of the data, accurate defect identification, and appropriate allocation of scarce funds. The Falling Weight Deflectometer (FWD) equipment can be used for rapid non-destructive techniques of assessing the condition of road pavement layers. Many road agencies in LMICs are acquiring FWDs and Pavement Management Systems (PMS) for data collection and maintenance planning. The analysis of FWD data requires rigorous backcalculation techniques that cannot be easily integrated into PMS. Surface deflection bowl parameters (DBP) have since been used for classification of pavement conditions. However, DBP do not yield values of layer elastic moduli, that are increasingly being used in rehabilitation design. Moreover, the DBP that are currently in use are applicable to roads with at least 50 mm asphalt concrete surfacing and have not been checked for validity on roads incorporating thin bituminous seals such as chip seal, and cape seal. Thus, a system that rapidly estimates layer elastic moduli from DBP and that can be easily integrated into PMS is required now and in the near future, for LMICs. Defective sections or pavement layers identified through this approach can then undergo more rigorous analysis using FWD specialist back-calculation software. This study developed equations that reliably estimate the layer moduli from DBP of pavements surfaced with thin bituminous seals. This was done through conducting FWD tests on selected road sections, conducting back-calculation using specialist software, and testing which DBP best correlates with the back-calculated elastic moduli. These equations are used to rapidly identify pavement layers and sections that are deteriorating season by season, and hence, target and plan appropriate maintenance interventions. [ABSTRACT FROM AUTHOR]

Using the method of asymptotic integration of the equations of the theory of elasticity, the axisym- metric problem of the theory of elasticity for a radially inhomogeneous transversally isotropic cylinder of small thickness is studied. Suppose that the elastic moduli are arbitrary continuous functions of the radius of the cylinder. It is assumed that the side part of the cylinder is fixed, and stresses are set at the ends of the cylinder, leaving the cylinder in equilibrium. Solutions have been determined having the nature of a boundary layer and are localized at the ends of the cylinder. The first terms of its asymptotic expansion coincide with the Saint-Venant edge effect in the theory of plates. The nature of the stress-strain state has been studied. It is shown that some boundary layer solutions may not be extinguished by propagating far from the ends. [ABSTRACT FROM AUTHOR]

This paper is the continuation of a previous study, which highlighted some inconsistencies in the RILEM guidelines for the interpretation of the diagonal compression test. Although improved compared to the ASTM guidelines, in fact, the RILEM guidelines underestimate the state of hydrostatic stress induced by the diagonal compression test at the center of the wallette. The new interpretation of the diagonal compression test proposed in this article shows that the RILEM guidelines actually underestimate both the hydrostatic and the deviatoric stress states at the center of the wallette. The new formulation complies with the linear elastic theory and allows us to use the diagonal compression test to identify the three elastic coefficients of masonry. In particular, it allows the identification of the Poisson ratio, which instead takes on a conventional value in the RILEM and ASTM guidelines. The difference of one order of magnitude between the conventional and proposed Poisson's ratio is in agreement with the experimental results on another brittle material, namely concrete. Finally, the new proposal fills the gap between the results provided by the two tests usually performed to identify the shear behavior of masonry: the diagonal compression test and the shear-compression test. [ABSTRACT FROM AUTHOR]

A theoretical model of the equation of state based on Eulerian finite theory for high pressure has recently been reported by Singh et al. The adopted model successfully predicted the elastic properties of geophysical minerals and prototype solids and the results were also found favourable with experimental data. We have derived the expression for pressure dependence elastic moduli using the proposed model of the equation of state. In this study, the elastic constants of two hcp-transition metals ∼ Co and Re as function of pressure are computed using these formulated expressions. The obtained high-pressure elastic constants are found to be well consistent with the previous theoretical results and show a good agreement with the experimental results. As a result, the present study may play a vital role in geophysical applications.

In the event of unanticipated events or emergency situations, such as equipment malfunctions or accidents, it is crucial for radiation shielding materials to preserve their structural integrity. Enhancing the fracture resistance of glasses has a wide range of benefits that extend to safety, durability, cost savings, energy efficiency, environmental considerations, technological innovation, consumer confidence, manufacturing efficiency, and reduced downtime. This research examines the characteristics of sodium-borate glasses with a nominal composition of 25Na2O-xGa2O3-(75-x)B2O3, (where x: 5, 10, 15, 20, 25, 27.5, and 30 mol%). The aim is to enhance fracture resistant qualities and radiation absorption with the addition of Ga2O3 into the glass composition. In addition to elastic moduli and mechanical properties, gamma-ray and fast neutron removal cross section values are determined for each glass sample. In addition to enhancing mechanical characteristics and elastic moduli, the use of Ga2O3 reinforcement has shown notable improvements in the gamma-ray and fast neutron absorption properties of sodium-borate glass samples. The NGB31.4 sample demonstrated the highest level of improvement in gamma-ray and neutron absorption characteristics. For example, the mass attenuation coefficients were calculated as 1.86645 cm2/g, 1.92189 cm2/g, 1.98875 cm2/g, 2.04052 cm2/g, 2.10506 cm2/g, 2.16271 cm2/g, and 2.17266 cm2/g for NGB5, NGB10, NGB15, NGB20, NGB25, NGB30.5, and NGB31.4 at 15 MeV photon energy, respectively. This enhancement was accomplished by incorporating Ga2O3 into the baseline sample at a mole percentage of 31.4 %. Hence, it can be concluded that the incorporation of Ga2O3 into sodium-borate glasses has the potential to serve as a systematic mechanism, leading to enhancements in mechanical strength and radiation absorption characteristics, thereby making these glasses more suitable for their intended applications. Among these samples, the greatest level of integration observed was 31.4 % mole Ga2O3. The lack of ability to examine the behavioral alterations resulting from higher Ga2O3 content in sodium-borate glasses may be regarded as a limitation of the present study. However, it is very advisable to do more research among the scientific community to thoroughly explore the potential impact of Ga2O3 on sodium-borate glasses.

The utilization of pultruded glass fibre-reinforced polymer composites (PGFRPC) to replace traditional wooden cross-arms in high transmission towers is a relatively recent development. While there have been numerous investigations into enhancing cross-arm structures, there remains a notable absence of research focused on the elastic characteristics of a full-scale PGFRPC cross-arm, particularly one enhanced with a honeycomb sandwich structure. To full-fill the gap, this paper presents an experimental and numerical study through cantilever beam flexural tests on assembled cross-arm condition to examine deflection behavior and the flexural creep response. For deflection behavior, the load was applied up to actual working load. For creep behavior, the hanging load was applied for 1000 h in open area condition followed ASTM D2990 standards. By using Findley's power law, confirming the ability of this empirical approach to simulate the viscoelastic response of the cross-arm. The results obtained prove that the addition of a honeycomb sandwich structure reduced deflection and improved resilience against bending forces, enhancing specific points' elastic modulus slightly. Long-term creep tests revealed Point Y3 had the highest strain, but the enhanced cross-arm displayed superior resistance and a shorter viscoelastic transition period, indicating increased stability. Besides that, the Findley's Power Law Model effectively represented creep behavior for both cross-arm types, with low errors. Over 50 years, both versions showed a significant reduction in average elastic modulus, with the enhanced variant 20 % stronger due to the honeycomb structure. In conclusion, this study validates the superior creep properties of the enhanced PGFRPC cross-arm and demonstrates the honeycomb sandwich structure's substantial role in increasing strength and extending the cross-arm's lifespan, making it a valuable enhancement for such applications.

Among all the active confinement techniques, the use of pre-tensioned stainless steel straps has recently gained much attention. The flexibility of the stainless steel straps allows us to bend and pass them through the thickness of the masonry, thus creating a three-dimensional strengthening system between the two opposite facings. The use of the same perforation for the passage of several straps closed in a loop generates a continuous strengthening system that prevents parts of the structure from falling and injuring the occupants during seismic events. However, the perforations can nullify the in-plane strengthening, as they act as cylindrical hinges and make the reinforcement system labile for certain strap arrangements. Diagonal compression tests on square masonry panels performed in the present study show that the straps improve neither strength nor ductility when running along the mortar head and bed joints, arranged in square meshes. Conversely, they improve both strength and ductility when the straps make angles of ±45° with the mortar joints. Furthermore, the experimental results show that the straps exert an anisotropic effect that decreases the apparent in-plane Poisson ratio. They also provide new insights into the diagonal compression test and allow formulating a new proposal for the pseudo-ductility factor. [ABSTRACT FROM AUTHOR]

Silicate glasses containing sodium, calcium, and phosphorus are known as bioactive glasses, which are utilized in the human body to support and fulfill living tissue functions. These glasses exhibit excellent physical and mechanical properties, making them suitable for radiation shielding applications. This study focuses on investigating the radiation absorption parameters of seven bioglasses. The densities of the samples were found to increase from 2.6383 to 3.2218 g/cm3 as the ZnO increased from 0.0 to 15 mol%. Also, the mass-attenuation-coefficient (i.e., MAC) was calculated via the Phys-X simulation code in the photonic-energy domain of 0.015–15.0 MeV, and the outcomes were compared with XCOM data. The computed MAC values have the following sequential order: MAC46MBG-0Zn < MAC65MBG-5Zn < MAC64MBG-7Zn < MAC60MBG-15Zn < MAC45MBG-4Zn < MAC44MBG-7Zn < MAC40MBG-15Zn. Other important parameters, such as the half- and tenth-value-layer (i.e., HVL, and TVL), mean-free-path (MFP), and effective-atomic-number (Zeff), were also determined. Among the bioactive-glasses studied, the bioglass encoded as 60MBG-15Zn, which contains uppermost amounts of silicate and zinc, had the lowest MFP, HVL, and TVL values but the highest Zeff values. Effective removal cross-section values (ΣR) were determined to assess the neutron safety effectiveness of the bio-glasses, and the results indicated that 60MBG-15Zn ([ZnO]/[SiO2] = 0.258) and 40MBG-15Zn ([ZnO]/[SiO2] = 0.375) had advanced neutron lessening character. The exposure- and adsorption-buildup factor (i.e., EBF and EABF) values were also calculated using the G-P least-square-fit model, which depends on the photon energy and MFP. The bioglasses with higher equivalent-atomic numbers were found to have the lowest EBF, and EABF values. Also, the calculated elastic-mechanical intrinsic of the bio-glasses, including the molar volume (Vm), which increased from 16.680 to 20.128, and the dissociation-energy (G), which varied from 56.012 to 63.771 kJ/cm3 were found to depend on ([ZnO]/[SiO2] molar ratio. [ABSTRACT FROM AUTHOR]

Samarium oxide (Sm2O3) and ytterbium oxide (Yb2O3) doped tungsten-tellurite glasses (TWSm), (TWYb) in the forms of 80 (TeO2)-(20−x)(WO3)−x(Sm2O3) and 80 (TeO2)-(20−x)(WO3)−x(Yb2O3) with x = 0,1.0,2.0,3.0,4.0 and 5.0 mol% were prepared by the melt-quenching technique. The XRD analysis for the two prepared glass systems verified the samples’ amorphous nature. The glass density (ρ) was measured by the Archimedes method. Both (ρ) and the molar volume (VM) of the two prepared systems showed an increase with increasing the concentrations of dopants Sm3+ and Yb3+. Longitudinal VL and shear VS wave velocities were measured at 5 MHz frequency using the pulse-echo technique. Longitudinal (L), shear (G), bulk (K), and Young’s moduli (E) have been founded. Moreover, Poisson’s (σ), Debye temperature (θD), softening temperature (TS), micro-hardness (H) have been founded for every glass sample. Elastic moduli showed an increase with increasing dopants concentration of (Sm2O3) or (Yb2O3). Moreover, the bulk modulus of (TWSm) glasses was higher than (TWYb) glasses. Mechanical properties of (TWSm) and (TWYb) are crucial parameter in manufacturing optical fibers. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate the transition metal oxides (CuO, TiO2) induced structural, optical, luminescence and elastic characteristics of (60 − x)B2O3 + 20K2O + 10ZnO + 10ZnF2 + xTMO glasses produced via the melt-quenching process. The prepared glass samples were comprehensively studied through various characterization techniques systematically using XRD, FTIR, and UV–Visible spectroscopic techniques. In addition, the elastic properties were evaluated using the Makishima–Mackenzie theoretical model. It was found from the structural studies by XRD show that the glass samples exhibit amorphous characteristics even after doping with TMOs. There is no significant variation in the physical parameters upon adding TMOs, indicating the structural stability of the prepared glasses and the occurrence of non-bridging oxygens in the glass matrix. while FTIR analysis revealed the predominance of borate groups for all the prepared samples. UV–Visible absorption spectral studies demonstrate the presence of prominent electronic transitions originated by incorporating dopant (CuO) in the case of BCu glass samples. In contrast, other glasses (B and BTi) show no signatures. Further, the estimated indirect energy band gap and Urbach energy values were higher than the base (host) glass. The elastic properties such as estimated elastic moduli describe the elastic behaviour of the prepared glasses. Among all the glasses, BCu glass stands out for its exceptional optical and elastic qualities. [ABSTRACT FROM AUTHOR]

The current research report aimed the use of a bioactive glass systems of the chemical composition (80-x)SiO2–15CaO–5P2O5–xB2O3; 0 (MBG) ≤ x ≤ 15 (15.0B-MBG) mol% as radiation protection candidate for γ-rays. The density (ρ) of the investigated glasses reduced slightly from 2.6785 to 2.6637 g/cm3 and the molar volume (Vm) increased from 23.7353 to 24.4042 cm3/mol. The mass attenuation coefficient (MAC) for photon energies ranging from 15 keV to 100 keV using the XCOM code and Phys-X software was estimated. The highest discrepancy among the MAC values calculated by XCOM and Phys-X was found less than 2.5% at 15.0 keV and 5% at 100 keV. In terms of the effective-atomic-number (Zeff), it found that the sample encoded as MBG had the uppermost Zeff. In general, the analysis showed that the selected MBG-15.0B-MBG glasses provide adequate protection against low-energy photons (i.e., E < 30 keV), but their shielding ability decreases at high energies (60 < E < 100 keV). In addition, the various elastic-mechanical intrinsic of samples were calculated, including the total dissociation energy (G), which decreased from 65.425 to 57.565 kJ/cm3 as the B2O3 content increased from 0.0 to 15.0 mol%. The Poisson's ratio (σ) improved from 0.41253 to 0.41603 and Young's modulus reduced from 79.110 to 72.510 GPa. Results shows a significantly impact of B2O3 insertion into the investigated glasses network. [ABSTRACT FROM AUTHOR]