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To support commercialization of the MgO–Al2O3–B2O–SiO2‐based low‐dielectric glass fibers, crystallization characteristics of the relevant glasses was investigated under various heat‐treatment conditions. The study focused on the effects of iron on the related thermal properties and crystallization kinetics. Both air‐cooled and nucleation‐treated samples were characterized by using the differential thermal analysis/differential scanning calorimeter method between room temperature and 1200°C. A collected set of properties covers glass transition temperature (Tg), maximum crystallization temperature (Tp), specific heat (ΔCp), enthalpy of crystallization (ΔHcryst), and thermal stability (ΔT=Tp—Tg). Using the Kinssiger method, the activation energy of crystallization was determined. Crystalline phases in the samples having various thermal histories were determined using powder X‐ray diffraction (XRD) and/or in situ high‐temperature XRD method. Selective scanning electron microscope/energy‐dispersive spectroscopy analysis provided evidence that crystal density in the glass is affected by the iron concentration. Glass network structures, for air‐cooled and heat‐treated samples, were examined using a midinfrared spectroscopic method. Combining all of the results from our study, iron in glass is believed to function as a nucleation agent enhancing crystal population density in the melt without altering a primary phase field. By comparing the XRD data of the glasses in two forms (bulk versus powder), the following conclusions can be reached. The low‐dielectric glass melt in commercial operation should be resistant to crystallization above 1100°C. Microscopic amorphous phase separation, possibly a borate‐enriched phase separating from the silicate‐enriched continuous phase can occur only if the melt is held at temperatures below 1100°C, that is, below the glass immiscibility temperature. The study concludes that neither crystallization nor amorphous phase separation will be expected for drawing fibers between 1200°C and 1300°C in a commercial operation.

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The development of new, advanced shielding materials has attracted great interest among scientists and engineers. Recently, various shielding materials have been developed, which could replace the toxic, heavy, and costly conventional shielding materials. In this paper, we present our new computational software, MIKE, to assist researchers in the process of calculating and analyzing different radiation shielding parameters, such as the linear attenuation coefficient, mass attenuation coefficient, and half-value layer. The shielding parameter equations were coded using MATLAB. Additionally, the computational tool can be used to calculate the physical and optical properties of the selected composition, such as the average molar weight, molar volume, and molar electronic polarizability. Moreover, this tool allows the user to analyze the shielding parameters and the transmission factors for a selected material against a wide range of ionizing radiation energies. The newly developed computational software has been compared with existing radiation-shielding codes, including Phy-X/PSD and WinXcom, in addition to the available experimental data in the literature. The computed values produced using the MIKE software show good agreement with values calculated using the available competitor software programs (WinXcom, Phy-X/PSD, and the Monte Carlo method) with percentage differences of less than 0.2%. Our user-friendly computational software could help researchers evaluate whether various shielding materials meet the requirements of radiation applications, such as diagnostic and therapy applications including mammography, general radiography, computed tomography (CT), nuclear medicine, and high-energy photons used in radiotherapy applications.

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This paper is focused on the design, fabrication and characterization of tellurite glass of composition TeO2–WO3–PbO in terms of La2O3addition.

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