ABSTRACT We investigated the effects of In3+ and Co2+ substitutions on the structural and magneti... more ABSTRACT We investigated the effects of In3+ and Co2+ substitutions on the structural and magnetic properties of Mg-Mn ferrites. The cation distribution technique was taken into account to estimate the magnetic interactions. Cation distribution was also used to investigate the ionic radii of tetrahedral and octahedral sites, oxygen positional parameter, site bond as well as edge lengths, bond lengths and bond angles. The ionic radius of tetrahedral site and octahedral site was observed to increase with the incorporation of In3+ and Co2+ ions respectively. Theoretical lattice parameter was observed to increase with the substitution of In3+ and Co2+ ions. In3+ substitution resulted in weakening of super-exchange interactions while in Co2+ substituted Mg-Mn ferrites, anisotropy was observed to play a decisive role in addition to bond lengths and bond angles.
ABSTRACT Sol-gel synthesized BaGdxFe12-xO19, (x = 0.0, 0.1, 0.2, 0.3) nanohexaferrites, have been... more ABSTRACT Sol-gel synthesized BaGdxFe12-xO19, (x = 0.0, 0.1, 0.2, 0.3) nanohexaferrites, have been explored for magnetic and microwave properties. X-ray diffraction studies revealed the hexagonal structure of the synthesized ferrites. The particle size was observed to be in the range 90–84 nm. The dc resistivity was found to be increasing with an increase in Gd3+ content and the variation of dc resistivity with temperature confirmed the semiconducting behavior of all nanohexaferrites. The observed values of saturation magnetization and coercivity, at room temperature, are 81.34 emu/g and 6020 Oe respectively which are very high as compared to the values ever reported till date. Additionally, we observed ultra-low magnetic loss (0.004 to 0.01) and dielectric loss (0.004 to 0.06) over the GHz frequency region. The obtained results make these nanohexaferrites a competent material for antenna applications up to C-band.
This paper initially highlights the rapid growth in the call centre (CC) sector in developing cou... more This paper initially highlights the rapid growth in the call centre (CC) sector in developing countries like India. It then makes a case for the investigation of human resource management (HRM) systems of call centres in India. The analysis is based on a two-phase empirical study. Phase one ...
Abstract This article considers a misspecified linear regression model in which misspecification ... more Abstract This article considers a misspecified linear regression model in which misspecification relates to the inclusion of some explanatory variables. Assuming the distribution of disturbances to be not necessarily normal, this paper investigates the ...
International journal of biological macromolecules, 2015
Nanocomposite materials are gaining grounds in the fields of medicine, environmental sciences and... more Nanocomposite materials are gaining grounds in the fields of medicine, environmental sciences and for basic studies. Herein, we have developed, a novel method for the preparation of chitosan-g-poly(acrylamide)/ZnS (abbreviated as CPAZ) nanocomposite using microwave radiations. The synthesized CPAZ nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermo gravimetric analysis (TGA). FTIR results established the grafting of acrylamide onto chitosan backbone. TEM analysis revealed the size of the CPAZ nanocomposite particles in the range of 19-26nm. XRD technique predicated the crystalline behavior of the nanocomposite. Therefore, XRD, TEM and FTIR spectrum analysis confirmed the formation of CPAZ nanocomposites. Zeta potential for CPAZ nanocomposite was found to be +28.2mV which indicated its stability. The CPAZ nanocomposites were investigated for drug release behavior and we found a maximum of 79% drug release at pH 2.2. Moreover, CPAZ nanocomposite was also found to be antimicrobial against Escherichia coli bacteria.
This paper initially highlights the rapid growth in the call centre (CC) sector in developing cou... more This paper initially highlights the rapid growth in the call centre (CC) sector in developing countries like India. It then makes a case for the investigation of human resource management (HRM) systems of call centres in India. The analysis is based on a two-phase empirical study. Phase one ...
ABSTRACT We investigated the effects of In3+ and Co2+ substitutions on the structural and magneti... more ABSTRACT We investigated the effects of In3+ and Co2+ substitutions on the structural and magnetic properties of Mg-Mn ferrites. The cation distribution technique was taken into account to estimate the magnetic interactions. Cation distribution was also used to investigate the ionic radii of tetrahedral and octahedral sites, oxygen positional parameter, site bond as well as edge lengths, bond lengths and bond angles. The ionic radius of tetrahedral site and octahedral site was observed to increase with the incorporation of In3+ and Co2+ ions respectively. Theoretical lattice parameter was observed to increase with the substitution of In3+ and Co2+ ions. In3+ substitution resulted in weakening of super-exchange interactions while in Co2+ substituted Mg-Mn ferrites, anisotropy was observed to play a decisive role in addition to bond lengths and bond angles.
ABSTRACT Sol-gel synthesized BaGdxFe12-xO19, (x = 0.0, 0.1, 0.2, 0.3) nanohexaferrites, have been... more ABSTRACT Sol-gel synthesized BaGdxFe12-xO19, (x = 0.0, 0.1, 0.2, 0.3) nanohexaferrites, have been explored for magnetic and microwave properties. X-ray diffraction studies revealed the hexagonal structure of the synthesized ferrites. The particle size was observed to be in the range 90–84 nm. The dc resistivity was found to be increasing with an increase in Gd3+ content and the variation of dc resistivity with temperature confirmed the semiconducting behavior of all nanohexaferrites. The observed values of saturation magnetization and coercivity, at room temperature, are 81.34 emu/g and 6020 Oe respectively which are very high as compared to the values ever reported till date. Additionally, we observed ultra-low magnetic loss (0.004 to 0.01) and dielectric loss (0.004 to 0.06) over the GHz frequency region. The obtained results make these nanohexaferrites a competent material for antenna applications up to C-band.
This paper initially highlights the rapid growth in the call centre (CC) sector in developing cou... more This paper initially highlights the rapid growth in the call centre (CC) sector in developing countries like India. It then makes a case for the investigation of human resource management (HRM) systems of call centres in India. The analysis is based on a two-phase empirical study. Phase one ...
Abstract This article considers a misspecified linear regression model in which misspecification ... more Abstract This article considers a misspecified linear regression model in which misspecification relates to the inclusion of some explanatory variables. Assuming the distribution of disturbances to be not necessarily normal, this paper investigates the ...
International journal of biological macromolecules, 2015
Nanocomposite materials are gaining grounds in the fields of medicine, environmental sciences and... more Nanocomposite materials are gaining grounds in the fields of medicine, environmental sciences and for basic studies. Herein, we have developed, a novel method for the preparation of chitosan-g-poly(acrylamide)/ZnS (abbreviated as CPAZ) nanocomposite using microwave radiations. The synthesized CPAZ nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermo gravimetric analysis (TGA). FTIR results established the grafting of acrylamide onto chitosan backbone. TEM analysis revealed the size of the CPAZ nanocomposite particles in the range of 19-26nm. XRD technique predicated the crystalline behavior of the nanocomposite. Therefore, XRD, TEM and FTIR spectrum analysis confirmed the formation of CPAZ nanocomposites. Zeta potential for CPAZ nanocomposite was found to be +28.2mV which indicated its stability. The CPAZ nanocomposites were investigated for drug release behavior and we found a maximum of 79% drug release at pH 2.2. Moreover, CPAZ nanocomposite was also found to be antimicrobial against Escherichia coli bacteria.
This paper initially highlights the rapid growth in the call centre (CC) sector in developing cou... more This paper initially highlights the rapid growth in the call centre (CC) sector in developing countries like India. It then makes a case for the investigation of human resource management (HRM) systems of call centres in India. The analysis is based on a two-phase empirical study. Phase one ...
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