Search

On the implication of tension force, viscoelastic materials deform in accordance with viscous and elastic characterization. Dilute polymer solutions portray the examples of viscoelastic liquids and Sutterby model successfully represent it due to high degree polymerization distributions. In addition, polymer aqueous solutions behave as shear thinning and thickening liquids in response to infinite shear stress so Sutterby fluid is considered as best model to depict the features of liquids at high stress magnitude. Diverse utilities of diluted polymeric solutions are encountered in industrial, biological and technological practices, for instance, agricultural sprayers, cleansing products, clay coaters, polymerized melts and many more. So, this research communicates theoretical and computational thermal assessment of Sutterby fluid containing radiation aspects over a linearly moving sheet embedded in stratified medium which exposes the novelty of work. Moreover, the impacts of magnetic field and chemical reactions are also obliged. So, the principal objective pertains to adumbrate flow behavior of Sutterby liquid in the attendance of aforementioned physical parameters. Mathematical formulation in view of governing relations are changed into non-dimensionalized form through transformation approach. Convergent and accurate solution is accessed through renowned numerical shooting procedure along with integrated Runge-Kutta scheme. The computed results of emerged parameters on velocity, concentration and thermal fields are revealed by means of snapshots. Magnitude of associated wall drag coefficient and reduced heat and mass fluxes are explained in graphical and tabular formats. The salient outcomes are as follows. Consequence of the proposed research investigation infers that augmenting power index momentum distribution decays whereas skin friction uplifts. Furthermore, it is inferred that concentration distribution amplifies against upsurging magnitude of solutal stratification parameter while opposite nature is noticed in case of temperature profile against associated stratification parameter. Additionally, it is concluded that escalating magnitude of radiation parameter tends to elevates the dimensionless temperature profile. Subsequently, rise in concentration profile against Schmidt number is observed whereas against Prandtl number temperature of fluid expressing declining aptitude. Also, declining response in momentum of fluid is manifested against Reynold and Deborah numbers.

The radiation-protection properties of the magnetic semiconducting quaternary compounds Cu2CoGeS4, Cu2CoGeSe4, and Cu2CoGeTe4 were examined in this study by using Phy-X/PSD software with the selected gamma energy (0.015–15 MeV). The radiation shielding coefficients such as mass and linear attenuation coefficients (MAC) and (LAC), half-value layer (HVL), and mean free path (MFP) of the present semiconductors were calculated. Also, the total electronic and atomic cross-sections (ECS and ACS), the effective atomic number (Zeff), the effective electron density (Neff), and the effective conductivity (Ceff) of these semiconductors were estimated to see how well they could protect against radiation. A comparative study occurred between the obtained results and the corresponding values of RS-253-G18, RS-360, RS-520 glasses, barite, chromite, and ferrite concrete. The results show that semiconducting samples with the best shielding performance outperform RS-253-G18, RS-360 glass, and RS-520 glass materials commonly used in nuclear applications. The Cu2CoGeTe4 sample had the highest MAC, LAC, and ACS, as well as the highest ECS and Zeff values. The other two semiconductor samples had the lowest MAC, ECS, and Zeff values. For photons, charged particles (electrons, protons, alpha particles), and C-ion, Phy-X/PSD allows the calculation of the Zeff quickly and precisely across the entire energy range. This study indicates that the semiconductor samples can be utilized as radiation attenuators for various nuclear fields.

Oxy-Fluoro Boro Tellurite glasses with formula (85-x) TeO2-xB2O3-5Bi2O3-5BaO-5LiF, where x = 0, 10, 20, 30, 40, 50 and 60 mol% were prepared by melt-quenching method. All the prepared glasses were extensively studied by several apparatus such as, X-ray diffraction (XRD), Fourier transform infrared spectroscopy, UV-Vis-NIR spectroscopy and differential scanning calorimetric (DSC). The optical energy gap and refractive index of the prepared glasses were estimated by UV-Vis spectra. Moreover, the thermal stability, transition activation energy, crystallization activation energy and Avrami parameter of prepared glasses were determined. The optical and thermal properties of the prepared glasses were found to be attributed to the concentrations of phase TeO4 and BO4 units in the glass network. From these results, Oxy-Fluoro Boro Tellurite glass could be used in the optical application such as fiber laser with doping rare earth.

Novel transparent glasses and glass-ceramics were fabricated by using melt-quenching technique with the following composition: TeO2–WO3–Nb2O5–KF–La2O3 doped with Tm2O3. Different properties and physical parameters of these glasses were investigated. As the concentration of Tm3+ ions increases, the linear refractive index increases while the optical energy gap decreases. With high Tm3+ ion concentration creates nucleation in the glass matrix this was investigated by x-ray diffraction. The Judd-Ofelt parameters used to calculate the electric and magnetic dipole transition probabilities, branching ratios, and radiative lifetimes of various excited states of Tm3+-doped parent glass. The emission cross section values for the 3F4→3H6 transition computed by using the McCumber hypothesis. The stimulated emission cross section σeFL(λ) and gain values of fabricated glass increase with Tm3+ ions. The spectroscopic quality and figure of merit (FOM) gain (σeFL(λ)×τR) factors were evaluated for the prepared transparent glass. Furthermore, the produced glasses were demonstrated to have low OH content and they have high fluoride ion content. These important properties of the glasses and glass-ceramics make them suitable for use in photonic applications.

This research investigates the influence of the concentration of Sm+3 ions on the properties of a new borosilicate glass system with the composition 50B2O3– 14SiO2- 20Li2O– 15Na2O– 1.0Al2O3-x(Sm2O3), where × = 100, 200, 300, 400, and 500 ppm. The glasses are characterized by XRD, FTIR, UV– Vis-NIR, and photoluminescence spectra. The XRD results proved that all glasses prepared are amorphous. Moreover, it was found that the values of density (ρ), and refractive index (n), rise with increasing of Sm+3 content. Otherwise, the value of molar volume, optical energy gap, and boron-boron distance decrease by increasing Sm+3 concentration. The structure of glasses studied was investigated by computing Internuclearri, Polaron radius rp, field strength F and the deconvolution of FTIR spectra. Judd-Ofelt theory was applied to clarify the structural changes and nature of the bonds of glasses prepared. Moreover, a spectroscopic quality factor, the branching ratio (βr), and lifetime (τ) are calculated with the use of Judd-Ofelt parameters. The color chromaticity of the glasses confirmed that the emission in the white-reddish orange region under 402 nm excitation is affected by the concentration of Sm3+ ions. The results of photoluminescence emission stimulated emission cross-section, and CIE chromaticity leads to the conclusion that the glass BSLNA5 are promising candidates as laser material for light-emitting diode (LED).

We manufactured a new series of borosilicate glass doped with Dy3+ ions using a glass-quenching technique. To achieve the unique luminescence properties of our prepared glass, rare earth (Dy2O3) was incorporated into the glass matrix. The photoluminescence spectrum revealed five intense emission bands allocated at wavelengths 483 nm, 575 nm, 665 nm, 712 nm, and 752 nm, attributed to the transition from 4F9/2 → 6H15/2, 4F9/2 → 6H13/2, 4F9/2→ 6H11/2, 4F9/2→ 6F3/2, and 4F9/2→ 6H9/2 respectively. From the emission results of prepared glass at excitation wavelength 350 nm, we used our glass as a new solid laser source for the production of white light. From radiative properties measurements, the luminescence performance of fabricated samples showed a strong transition, with limited transition life and high values of branching ratio. Additional physical parameters were evaluated, such as density, optical packing density, and molar volume. By X-ray diffraction, we observed that all the prepared samples were of the amorphous phase. Fourier Transform Infrared Spectroscopy demonstrated the effect of incorporating Dy2O3 on the structure of our prepared glass. From the spectrum of absorption transitions, optical band gap Eg, refractive index (n), and Urbach energy (ΔE) were obtained. To research glass bonding nature, Judd-Ofelt strength parameters (Ωλ and λ = 2, 4, 6) were obtained; these parameters were used to achieve the spectroscopic efficiency factor, branching ratios (βr), and lifetime (τ). Moreover, the cross-sections of emission and absorption of our prepared glass was estimated. Finally, our cumulative study findings indicate that these manufactured samples may be used in luminescent display devices as a white light laser diode (W-LED).

Tellurite glass (TLZNT) with compositions 75TeO2–5Li2O–10ZnO–(10–x) Nb2O5−x Tm2O3, (doped with x = 0, 0.5, 1.0, 1.5, 2, and 2.5 in mol%) were prepared through the melt quenching technique. In the present work, the glass transition value slightly decreased from 351 to 347 °C otherwise thermal stability ΔTchangesfrom118to164°C of (TLZNT) glasses, investigated by using differential scanning calorimetry (DSC). The influence of Tm3+ ions (RE) on the structure of the TLZNT glasses was studied through different techniques such as X-ray pattern diffraction and Raman/Fourier transform infrared spectra. Moreover, the ratio of the relative bridging oxygen (BO) to non-bridging oxygen (NBO) in the prepared glass network was determined. Next, the packing density of oxygen, density, molar refraction, molar volumes, metallization criterion, molar polarizability, and linear refractive index of the prepared glasses were computed. The optical energy gap, the Judd–Ofelt parameters (J–O), the radiative branching ratio (βR), and the radiative lifetime (τR) of Tm3+ in TLZNT glasses were determined. The absorption cross section (σABS), emission cross section (σEMIS), and gain coefficient (σGA) were evaluated in the range wavelength of 1500–2000 nm. The high value of σEMIS(1.50 × 10−20 cm2) of the 3H6 → 3F4 transition of TLZNT3 glass was reported. We produced TLZNT glasses in which the addition of Tm2O3 improved the ΔT against nucleation and crystallization what is in good agreement with the decrease of the average force constant (F-) from 225 to 221.7 N/m with increasing Tm2O3. For the 1870 nm emission band, the emission cross section was determined to be approximately 1.5 × 10−20 cm2. Finally, the results herein will denote that the TLZNT glasses are a promising solid material for optical applications that could be excited by a commercial laser diode (LD).

The thermal properties and the kinetic parameters of TeO2–Li2O–ZnO–Nb2O5–Yb2O3 glass series have been evaluated as a function of increasing Yb2O3 content. The theoretical elastic properties and the quantitative analysis (the link between the elastic features and the changed chemical composition of the glass) have been determined by the use of bond compression and Makishima–Mackenzie models. The thermal analysis Differential Scanning Calorimetry (DSC) test was used for estimating the glass characteristics temperatures, thermal stability, and non-isothermal kinetic parameters at the heating rates (β) 10, 15, 20 and 25 K/min. The activation energies of the glass transition 〈Eg〉 and crystallization 〈Ec〉, as well as the order of the crystallization reaction (n), have been computed by different models with clear consistency and harmony between them. It was found that the characteristics temperatures of transition (Tg), softening (Ts), the onset of the crystallization (Tx) and the crystallization (Tc) increased with increasing the heating rate. Also, the results showed the higher thermal stability values (>100 K) for the understudied glass which is confirmed by KSP and ((Tc–Tg)/Tg) parameters values. Calculating of (n) showed that the crystallization started with surface nucleation and finished with bulk volume nucleation with rising Yb2O3 (mol %). The computed elastic moduli were linked with the interpretation of the thermal parameters to give a comprehensive image of the studied glass system.

This article aims to study the detailed thermal behavior, characterization of kinetics and the luminescence properties of TeO2–Li2O–ZnO–Nb2O5–Er2O3 glass system as a function of increasing Er2O3 (mol%). Kinetic parameters of the glass series have been studied by the data obtained from the differential scanning calorimetry (DSC) under non-isochronal circumstances at heating rates (β) 10, 15, 20 and 25 K min−1 using the continuous-heating technique. The glass thermal stability (ΔT), the thermal relaxation resistance (ΔS) and the glass stability parameter (KSP) have been calculated to state the applicability of using the glass in specific fields and applications. Activation energies of both the glass transition (Eg) and crystallization (Ec) processes were determined from the shift of the transition (Tg) and crystallization (Tc) temperatures with the different heating rates using Kissinger’s and Ozawa’s techniques. The kinetic Avrami number (order of the crystallization reaction) (n) was also calculated to define the mechanism of the crystallization process. Quantitative interpretation of the kinetic parameters (the relation between thermal and structural properties with changing the chemical composition) also has been provided. The luminescence properties showed that the glass with the least concentration of Er2O3 (0.5 mol %) exhibited the higher emission intensity which might be a suitable candidate for the green laser applications. Keywords: Tellurite glass, Kinetics, Luminescence, Erbium

The prepared glass samples within the composition (85-x) TeO2-xB2O3-5Bi2O3-5SrCl2-5LiF (TBBSL) with x = 0, 10, 20, 30, 40, 50 and 60 mol% were synthesized. The X-ray diffraction patterns (XRD) showed the amorphous nature of the system. The density (ρ), molar volume (vm) and oxygen packing density (OPD) have been measured and calculated. The Fourier Transform Infrared (FTIR) of TBBSL glasses showed the presence of TeO3, TeO4, BO3, BO4, LiF, SrO and BiO6. Also, FTIR spectra identified that the substitution of B2O3 with TeO2 in glass system led to convert the TeO4 to TeO3 and the formation of bridging structure Te-O-B with increasing the B2O3 mol%, consequently the BO4 units convert to BO3 and so the number of non-bridging oxygen (NBO) increases. The optical band gaps (Eopt), the Urbach energy (ΔE) and refractive index (n) have been calculated from optical absorption spectra. Thermal characterization was determined by using Differential Scanning Calorimetry (DSC) at different heating rates 10, 15, 20, 25 °C/min. The prepared glasses showed high thermal stability. High reflective index and higher thermal stability made the synthesized glass system is a suitable candidate for the large bulk glass and optical fiber production. Keywords: Oxyhalide tellurite glasses, FTIR, Uv–vis spectroscopy, Thermal analysis