• Effect of annealing temperature on Cu2O thin films prepared by thermal oxidation methodEffect of annealing temperature on Cu2O thin films prepared by thermal oxidation method

    Abstract: We report a facile process to fabricate cuprous thin films by thermal oxidation of copper substrates. Structure and phase identification were studied by X-ray diffraction measurement and Raman spectroscopy. Scanning electron microscopy was utilized to study surface morphology of the as-fabricated thin films and optical properties of th...

    pdf6 trang | Chia sẻ: thanhle95 | Ngày: 13/07/2021 | Lượt xem: 282 | Lượt tải: 0

  • Investigation on structure of TeO2-B2O3-SiO2-Al2O3-KF glassesInvestigation on structure of TeO2-B2O3-SiO2-Al2O3-KF glasses

    1. Introduction In recent decades, there has been an increasing attraction in synthesis and studies of structural and physical properties of heavy metal oxide glasses due to their diversity applications in optical field [1- 3]. Among these glasses, tellurite glasses are technologically and scientifically important due to their outstanding prope...

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  • Study of structure transition and crystallization of amorphous silica under compressionStudy of structure transition and crystallization of amorphous silica under compression

    Abstract: In this work, we use molecular dynamic (MD) simulation to study the structure transition and crystallization of amorphous silica (SiO2) under compression. The structural evolution of amorphous SiO2 is explained through radial distribution function, coordination number distribution, bond angle distribution and visualization. Simulation ...

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  • Real-life task in mathematics teaching: A case of statistics teaching in order to educate some economic knowledge for students at high schoolReal-life task in mathematics teaching: A case of statistics teaching in order to educate some economic knowledge for students at high school

    Tóm tắt: Dạy học toán gắn với thực tiễn đang là một yêu cầu, một xu hướng trong dạy học Toán ở trường phổ thông của Việt Nam. Những luận giải về vấn đề “thực tiễn” và việc khai thác các “nhiệm vụ thực tiễn” trong dạy học môn Toán hiện còn nhiều điều chưa thực sự rõ ràng. Nghiên cứu này góp phần đưa ra những quan điểm về “nhiệm vụ thực tiễn” và v...

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  • Investigation of pressure effect on the structure of 3Al2O3.2SiO2 systemInvestigation of pressure effect on the structure of 3Al2O3.2SiO2 system

    Abstract: This paper studies the structure of the Mullite system (3Al2O3.2SiO2) by Molecular Dynamics simulation (MDs) using the Born–Mayer–Huggins pair interaction and periodic boundary conditions. The simulation was performed with model of 5250 atoms at different pressure and at 3500 K temperature. The structural properties of the system were ...

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  • Influences of PbS quantum dot layers on power conversion efficiency of single junction GaAs solar cellsInfluences of PbS quantum dot layers on power conversion efficiency of single junction GaAs solar cells

    Abstract: This paper investigates how PbS coating layers influence the characteristics of GaAs single junction solar cells through I-V characteristic measurements, optical reflectance spectra, and quantum efficiencies. To determine the expected influence, PbS quantum dots were coated on the surface of single junction GaAs solar cells by a drop c...

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  • Optical properties and white light emission of Dy3+doped alumino boro-tellurite glassesOptical properties and white light emission of Dy3+doped alumino boro-tellurite glasses

    Abstract: Dy3+doped alumino boro-tellurite (ABT) glasses xB2O3+(80-x)TeO2+10Al2O3+10CaO+ 0.5Dy2O3 (where x = 35; 45 and 55) have been prepared by melting method. Their optical properties were studied through absorption, luminescence spectra and decay time measurements. Judd-Ofelt (JO) intensity parameters (Ωλ, λ = 2, 4 and 6) were determined usi...

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  • Improvement of critical current density in Bi-2223 superconductor by Ag-dopingImprovement of critical current density in Bi-2223 superconductor by Ag-doping

    Abstract: In this study, high-Tc superconducting polycrystalline Bi-2223 undoped sample (A0) and 5wt.% Ag-doped sample (A5) were prepared by solid-state reaction method at 8550C with sintering time of 8 days. The X-ray powder diffraction (XRD) results show that the major phase of these samples was Bi-2223. The volume ratio of Bi-2223 phase incre...

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  • Synthesis and Characterization of Ni2+-Doped SnO2 PowdersSynthesis and Characterization of Ni2+-Doped SnO2 Powders

    Abstract: In this study, SnO2:Ni2+ powders with dopant contents ranging from 0.0 to 12 mol% were synthesized by sol-gel method. The samples were characterized by X-ray diffraction (XRD) Raman spectroscopy, energy-dispersive X-ray spectrometer (EDS) and photoluminescense (PL) spectra. The XRD analysis shows that the samples doped with low Ni- con...

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  • Cremona group functor and its lie algebraCremona group functor and its lie algebra

    Abstract. Let Crn(k) = Bir(Pn k ) denote the set of all birational maps of the projective space Pn k over a field k. It is clear that Crn(k) is a group under composition of dominant rational maps; called the Cremona group of order n. This group is not an algebraic group. It was studied for the first time by Luigi Cremona (1830 - 1903), an Italia...

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