Journal Articles - Natural Science - 2022
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PublicationSome estimates for rough Hausdorff operators on the Heisenberg group( 2022)The purposes of this article is to establish some necessary and sufficient conditions for the boundedness of the rough Hausdorff operators on weighted Herz, central Morrey and Morrey–Herz spaces on the Heisenberg group. By applying the block decomposition method, the authors also obtain the boundedness of the rough Hausdorff operators on weighted Herz spaces for the case p 2 ð0; 1Þ.
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PublicationBoundedness of Hardy–Ces`aro operators on variable exponent Morrey–Herz spaces( 2022)In this paper, we give the necessary and sufficient conditions for the boundedness of Hardy–Ces`aro operators on some weighted function spaces such as the weighted central Morrey, weighted local central Morrey, weighted non-local central Morrey, weighted Herz and weighted Morrey–Herz type spaces with variable exponent
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PublicationEnabling Cognitive Radio in NOMA Assisted Reconfigurable Intelligent Surfaces: Outage Performance Analysis( 2022)We have derived the closed-form expressions for outage probability (OP) at both the users and compared their performance in the presence of CR networks. The results show that, in the presence of CR, the number of meta-surfaces in RIS can significantly enhance the outage performance of the users. The comparison of both users’ performance has manifested that near users will have better outage performance compared to the far users.
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PublicationJudd-Ofelt analysis of Eu3+ and adjustable emission in Eu3+/Eu2+ co-doped sodium aluminosilicate glasses( 2022)Europium-doped sodium aluminosilicate glasses were synthesized by using the melt quenching technique. X-ray diffraction, photoluminescence spectra and luminescence decay of Eu3+ ions in glasses were investigated to estimate structural and optical properties of the prepared glasses. Phonon energies, Judd-Ofelt (JO) intensity parameters Ωλ (λ = 2, 4, 6) and radiative properties such as transition probability (A), radiative lifetime (τ), and branching ratio (βR) of Eu3+ ions in the prepared glasses were determined and Eu3+ emission may be suggested for suitable laser applications because of its high value of βR = 70.8%. The adjustable emission of Eu3+/Eu2+ from red light to blue light can be reached by heating the prepared glasses in H2 gas with various temperature and heating time. The reduction process from Eu3+ to Eu2+ ions in the glasses increases and maximum of Eu2+ emission shifts to the long wavelength with the increasing of temperature and heating time, that indicated the increase of the crystal field of sodium aluminosilicate heated in H2 gas.
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PublicationMesoporous alumina: A comprehensive review on synthesis strategies, structure, and applications as support for enhanced H2 generation via CO2-CH4 reforming( 2022)Lately, the generation of hydrogen out from carbon dioxide (CO2) - methane (CH4) reforming has been touted as a feasible option for reducing two of the most harmful greenhouse gases (CO2 and CH4) in the atmosphere. However, this technology typically suffered from catalyst deactivation triggered by sintering and coke deposition. Therefore, designing a feasible catalyst by making efficient support selections is vital for overcoming this challenge. Mesoporous alumina (MA) has aroused great attraction attributed to their potential applications as catalysis supports resulted from their high surface areas combined with tunable, narrow, and uniform pore size distribution, as well as their ability to constrain active metal from sintered and deactivated during the reaction. These materials' morphology, composition, and pore structure can be directly tailored during synthesis by altering the synthesis parameters like the type of the surfactants/templates employed, pH conditions, or selection of alumina precursors. As a result, this review's major focus is on synthesizing unique MA using a range of synthesis routes and conditions. Apart from that, this review also focuses on the applications and performance of MA as catalyst support during the CO2-CH4 reforming. We believe that this effort provides the complete grasp of MA contribution towards improving the CO2-CH4 reforming activity.