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Papers by Asghari Maqsood
Key Engineering Materials, May 22, 2012
ABSTRACT
Indian Journal of Physics, Mar 14, 2014
Journal of Alloys and Compounds, Oct 1, 2010
Journal of Magnetism and Magnetic Materials, Sep 1, 2007
Sr-hexa ferrites with the addition of Si (0.5 wt%) and Ca (0.5 wt%) have been prepared by solid-s... more Sr-hexa ferrites with the addition of Si (0.5 wt%) and Ca (0.5 wt%) have been prepared by solid-state reaction method with sintering time variation ranging from 2 to 10 h. The structural characterization of the samples confirmed the major phase of Sr-hexa ferrite. Average grain size was found within the range of 1-4 μm. Vicker hardness increased from 512 to 1187 Hv. The coercivity and remanence had the ranges from 596 to 4255 Oe and 324 to 516 G, respectively. The DC electrical resistivity measurements were carried out by two-probe method as a function of temperature from 303 to 723 K. The room temperature DC resistivity increased from 1.67×10 6 to 2.89×10 8 Ω cm in turn the activation energy also increased from 0.314 to 0.495 eV. The DC electrical resistivity decreased while drift mobility increased with the rise in temperature, ensuring the semi-conducting behavior. Dielectric properties were studied as a function of frequency in the range of 80 Hz to 1 MHz at room temperature.
Journal of Superconductivity and Novel Magnetism, 2008
ABSTRACT Superconducting samples with nominal composition Bi1.3V0.3Pb0.4Sr2Ca2Cu3O δ are prepared... more ABSTRACT Superconducting samples with nominal composition Bi1.3V0.3Pb0.4Sr2Ca2Cu3O δ are prepared by the solid state reaction method. The samples are characterized by X-ray diffraction, scanning electron microscopy, DC electrical resistivity, critical current density, AC magnetic susceptibility, thermal conductivity and thermoelectric measurements. The room temperature X-ray diffraction pattern of the sample indicated the presence of large amount of Bi-(2223) phase along with minor amount of Bi-(2212) phase. The standard four-probe technique is applied to measure DC electrical resistivity in the temperature range from 300 to 77 K. The onset temperature T c (onset) and zero resistivity critical temperature T c (R=0) are found to be 112±1 K and 106±1 K, respectively. The low field AC magnetic susceptibility is also measured as a function of temperature. Thermal conductivity and thermoelectric power of large disc-shaped cylindrical samples are measured as a function of temperature from 300 to 77 K. The increase in thermal conductivity is observed below and above T c (R=0). The estimation of the resistivity change due to scattering by phonons and impurities has been discussed.
Electronic Materials Letters, 2012
Journal of Alloys and Compounds
Microelectronics International, 2005
ABSTRACT
Crystal Research and Technology
Two-source thermal evaporation technique was used to prepare HgxCd1-xTe thin films onto scratch f... more Two-source thermal evaporation technique was used to prepare HgxCd1-xTe thin films onto scratch free transparent glass substrates. The structural investigations revealed that thin films were polycrystalline in nature. Transmittance measurements in the wavelength range (500-2700 nm) were used to calculate optical constants. The analysis of the optical absorption data showed that the optical band gap was of indirect type. In the composition range 0.05< x < 0.25 the films exhibited an optical band gap between 1.29 and 0.98 eV. In the same composition range the films were p-type and exhibited a resistivity, which varied between 102 and 10-1 Ω-cm.
Key Engineering Materials, May 22, 2012
ABSTRACT
Indian Journal of Physics, Mar 14, 2014
Journal of Alloys and Compounds, Oct 1, 2010
Journal of Magnetism and Magnetic Materials, Sep 1, 2007
Sr-hexa ferrites with the addition of Si (0.5 wt%) and Ca (0.5 wt%) have been prepared by solid-s... more Sr-hexa ferrites with the addition of Si (0.5 wt%) and Ca (0.5 wt%) have been prepared by solid-state reaction method with sintering time variation ranging from 2 to 10 h. The structural characterization of the samples confirmed the major phase of Sr-hexa ferrite. Average grain size was found within the range of 1-4 μm. Vicker hardness increased from 512 to 1187 Hv. The coercivity and remanence had the ranges from 596 to 4255 Oe and 324 to 516 G, respectively. The DC electrical resistivity measurements were carried out by two-probe method as a function of temperature from 303 to 723 K. The room temperature DC resistivity increased from 1.67×10 6 to 2.89×10 8 Ω cm in turn the activation energy also increased from 0.314 to 0.495 eV. The DC electrical resistivity decreased while drift mobility increased with the rise in temperature, ensuring the semi-conducting behavior. Dielectric properties were studied as a function of frequency in the range of 80 Hz to 1 MHz at room temperature.
Journal of Superconductivity and Novel Magnetism, 2008
ABSTRACT Superconducting samples with nominal composition Bi1.3V0.3Pb0.4Sr2Ca2Cu3O δ are prepared... more ABSTRACT Superconducting samples with nominal composition Bi1.3V0.3Pb0.4Sr2Ca2Cu3O δ are prepared by the solid state reaction method. The samples are characterized by X-ray diffraction, scanning electron microscopy, DC electrical resistivity, critical current density, AC magnetic susceptibility, thermal conductivity and thermoelectric measurements. The room temperature X-ray diffraction pattern of the sample indicated the presence of large amount of Bi-(2223) phase along with minor amount of Bi-(2212) phase. The standard four-probe technique is applied to measure DC electrical resistivity in the temperature range from 300 to 77 K. The onset temperature T c (onset) and zero resistivity critical temperature T c (R=0) are found to be 112±1 K and 106±1 K, respectively. The low field AC magnetic susceptibility is also measured as a function of temperature. Thermal conductivity and thermoelectric power of large disc-shaped cylindrical samples are measured as a function of temperature from 300 to 77 K. The increase in thermal conductivity is observed below and above T c (R=0). The estimation of the resistivity change due to scattering by phonons and impurities has been discussed.
Electronic Materials Letters, 2012
Journal of Alloys and Compounds
Microelectronics International, 2005
ABSTRACT
Crystal Research and Technology
Two-source thermal evaporation technique was used to prepare HgxCd1-xTe thin films onto scratch f... more Two-source thermal evaporation technique was used to prepare HgxCd1-xTe thin films onto scratch free transparent glass substrates. The structural investigations revealed that thin films were polycrystalline in nature. Transmittance measurements in the wavelength range (500-2700 nm) were used to calculate optical constants. The analysis of the optical absorption data showed that the optical band gap was of indirect type. In the composition range 0.05< x < 0.25 the films exhibited an optical band gap between 1.29 and 0.98 eV. In the same composition range the films were p-type and exhibited a resistivity, which varied between 102 and 10-1 Ω-cm.