Steklo i Keramika (Glass and Ceramics). Monthly scientific, technical and industrial journal

 

ISSN 0131-9582 (Online)

VOL 99, No. 5 (2026)

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  • LUMINESCENT WAVEGUIDES IN BI-DOPED QUARTZOID GLASS, WRITTEN BY FEMTOSECOND LASER PULSES

    • Pages: 3-9
    • Views: 25
    The formation of waveguides in the bulk of sintered nanoporous glass pre-impregnated in a bismuth nitrate solution was demonstrated. The influence of laser irradiation regimes on the refractive index change and luminescence intensity in fs laser beam-written tracks was studied. It was shown that the relative luminescence intensity of the formed waveguides depends significantly on the impregnating bismuth nitrate solution concentration. The waveguides exhibit broadband (FWHM ~150 nm) luminescence in the near infrared region (1200…1500 nm) when pumped at a wavelength of 808 nm. This indicates potential for using the formed waveguides as the active medium of waveguide laser amplifiers.
  • ELECTRICAL PROPERTIES OF OXIDE CERAMICS WITH PYROCHLORE STRUCTURE CONTAINING MANGANESE AND NICKEL

    • Pages: 10-17
    • Views: 24
    The electrical properties of bidoped oxide pyrochlore Bi6/5Mn1/3Ni1/3Ta4/3O6+? (sp. gr. Fd-3m, a = 10.5038(9) ?), synthesized for the first time by the solid-phase method, were studied. According to scanning electron microscopy data, the ceramics is characterized by a porous microstructure formed by randomly oriented grains of an elongated shape. The average crystallite size determined by X-ray diffraction is 65 nm. The electrical properties of the samples were studied using an immittance analyzer at temperatures of 100…450 °C in the frequency range of 25…106 Hz. An electrical model of the sample was constructed in the form of an equivalent circuit, on the basis of which the relative permittivity (?25), the dielectric loss tangent (4 10–3 at a frequency of 106 Hz) and the activation energy of through conductivity (0.7 eV) were calculated. Two polarization mechanisms were established. Electronic polarization dominates in the high-frequency region. At low frequencies, ion-migration polarization is observed, with parameters close to the Warburg theoretical model.
  • INFLUENCE OF FUNCTIONAL ADHESIVE SUBLAYERS ON THE INTEGRITY OF HETEROGENEOUS COMPOSITIONS OF AIRCRAFT GLAZING

    • Pages: 18-23
    • Views: 38
    In this paper the effect of chemical modification of the surface of monolithic polycarbonate on the adhesive strength of heterogeneous laminated glass are considered. The effect of chemical modification of the surface on ensuring stable adhesion between transparent chemically and physically incompatible materials is shown. The use of chemical surface modification in the production of heterogeneous aircraft glazing is proposed to improve its operational reliability and safety.
  • STUDY OF THE HOMOGENEITY OF THE CHEMICAL COMPOSITION OF LEAD-GERMANATE GLASSES BY LASER-INDUCED BREAKDOWN SPECTROSCOPY METHOD

    • Pages: 24-38
    • Views: 38
    Lead-germanate glasses are a promising material for creating optical elements. However, producing such glasses with a high degree of homogeneity is associated with several technological challenges. During synthesis, phase separation can occur, in which the glass separates into several amorphous phases with different chemical compositions, negatively affecting its optical properties (scattering, absorption). Determining the exact composition is further complicated by the high lead content, which can distort analytical results. Uneven evaporation of components from the glass surface and insufficient mixing of the melting during synthesis can also lead to local variations in composition. To address these issues, a method for chemical composition mapping based on laser-induced breakdown spectroscopy (LIBS) is proposed, allowing for the visualization of the spatial distribution of elements on the sample surface. This paper presents the results of a LIBS study of lead-germanate glass samples of various compositions and demonstrates the differences in the results obtained depending on the spectral data processing method.
  • INVESTIGATION OF THE EFFECT OF MECHANOACTIVATION OF LOCAL RAW MATERIALS ON THE STRENGTH PROPERTIES OF SULFURE CONCRETE

    • Pages: 39-44
    • Views: 23
    Technological solutions have been developed to produce composite sulfur-containing building materials based on local mineral raw materials with a high level of technical properties for use in the climatic conditions of the North and the Arctic. The use of methods of mechanical activation of mineral fillers of sulfur binder allows the use of substandard mineral raw materials in the technologies of sulfur concrete and to obtain sulfur concrete materials with a high level of physical and mechanical properties and with a strength class up to B45. The influence of the method of mechanical activation of mineral powders from natural zeolite on the formation of the structure of concretes based on sulfur binder and limestone crushing screens has been established. The effects of activation time on the properties of the developed composites have been studied, and the advantage of using the method of mechanical activation of mineral powders from natural zeolite for obtaining stable sulfur binders and concretes based on them with a high range of technical properties has been demonstrated. The use of filler mechanoactivation techniques allows for the use of substandard mineral raw materials in seroconcrete technologies, resulting in materials with high levels of physical and mechanical properties.
  • DEVELOPMENT OF NANOMODIFIED CEMENT USING MICROSILICA, POLYCARBOXYLATE AND DUNE SAND: OPTIMIZATION OF COMPOSITION AND STRENGTH CHARACTERISTICS

    • Pages: 45-61
    • Views: 20
    This study presents the development and experimental validation of nanomodified cement obtained by joint grinding of clinker, gypsum, microsilica, polycarboxylate superplasticizer, and dune sand. The optimal composition and technological parameters providing increased strength and performance properties of the binder were studied. A series of cement systems with varying clinker and sand content was prepared, while the amount of gypsum (5 %) and modifier (10 %) remained constant. The results showed that mechanical activation in a ball mill for 110 minutes provided a nanostructured material with a specific surface area of 5500…5700 and an average particle size of 3.5…3.7 ?m. Strength tests have shown that the optimal clinker content is 70...80 %, while replacing up to 20 % of clinker with dune sand does not reduce strength. In this composition, the 28-day compressive strength reached 110…115 МПа, exceeding the control samples by 25…30 %. It was also established that the optimal water-to-cement ratio (W/C = 0.18…0.20) ensures dense microstructure and maximum strength, while higher W/C values lead to increased porosity and strength loss. The findings highlight the potential of nanomodified cement technology for reducing clinker consumption, improving performance, and enhancing the environmental sustainability of cement production.
  • DIELECTRIC PROPERTIES OF MANGANESE-DOPED ZINC TITANATE (MnxZn1-xTiO3, x = 0.1; 0.3, & 0.5) CERAMICS FOR HIGH K-MICROWAVE APPLICATIONS

    • Pages: 62-64
    • Views: 35

    The microstructure and dielectric properties of manganese-doped zinc titanate (MnxZn1–xTiO3) ceramic samples were investigated as a function of manganese concentration (x = 0.1; 0.3, & 0.5). XRD analysis confirmed that the samples exhibited an ilmenite hexagonal structure, indicating the structural evolution of the material. The dielectric constant was influenced by the Mn content and increased with increasing temperature and decreased with increasing frequency. According to the findings, the dielectric loss and dielectric constant increased with temperature and decreased with frequency. The addition of trace amounts of zinc to the manganese titanate ceramics resulted in a substantial increase in the dielectric constant. The substitution of zinc ions for manganese ions effectively enhanced the dielectric properties of the ceramic samples, which highlights their potential for advanced applications.