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R D K Misra - One of the best experts on this subject based on the ideXlab platform.

  • enhanced antibactericidal function of w4 doped titania coated Nickel Ferrite composite nanoparticles a biomaterial system
    Acta Biomaterialia, 2008
    Co-Authors: Bhanukiran Sunkara, R D K Misra
    Abstract:

    Abstract The study demonstrates a distinct enhancement of antimicrobial activity of W 4+ -doped titania that is coated on Nickel Ferrite nanoparticles in comparison to undoped titania. The composite nanoparticles were synthesized by uniquely combining reverse micelle and chemical hydrolysis synthesis methods [Rana S, Rawat J, Misra RDK, Acta Biomater 2005;1:691]. The superior antimicrobial activity of W 4+ -doped titania is related to the inhibition of electron–hole recombination and decrease in the band gap energy of titania. The function of the Ferrite is to facilitate the removal of nanoparticles from the sprayed surface using a small magnetic field. The coating of Ferrite nanoparticles with titania retains superparamagnetic character and magnetic strength of composite nanoparticles signifying non-deterioration of magnetic properties and promoting their use as removable antimicrobial photocatalyst nanoparticles.

  • anti microbial activity of doped anatase titania coated Nickel Ferrite composite nanoparticles
    Materials Science and Technology, 2007
    Co-Authors: J Rawat, S Rana, M M Sorensson, R D K Misra
    Abstract:

    AbstractIn the previous paper (S. Rana , R. S. Srivastava, M. M. Sorensson and R. D. K. Misra, Materials Science & Engineering B, 2005, 119, 144–151), the processing of composite nanoparticles consisting of a photocatalytic shell of anatase titania and a magnetic core of Nickel Ferrite by combining reverse micelle and chemical hydrolysis techniques was described. The present study demonstrates the anti-microbial performance of undoped and doped as synthesised composite nanoparticles. The doping process involved heat treatment at ∼400°C for 20 min. Heat treatment of the composite nanoparticles does not influence the magnetic characteristics of the Nickel Ferrite core.

  • antimicrobial function of nd3 doped anatase titania coated Nickel Ferrite composite nanoparticles a biomaterial system
    Acta Biomaterialia, 2006
    Co-Authors: S Rana, J Rawat, M M Sorensson, R D K Misra
    Abstract:

    Abstract The present study describes and makes a relative comparison of the antimicrobial function of undoped and neodymium-doped titania coated-Nickel Ferrite composite nanoparticles processed by uniquely combining the reverse micelle and chemical hydrolysis approaches. This methodology facilitates the formation of undoped and doped photocatalytic titania shells and a magnetic Ferrite core. The Ferrite core is needed to help in the removal of particles from the sprayed surface using a small magnetic field. Doping of the titania shell with neodymium significantly enhances the photocatalytic and anti-microbial function of the core–shell composite nanoparticles without influencing the magnetic characteristics of the Nickel Ferrite core. The increased performance is believed to be related to the inhibition of electron–hole recombination and a decrease in the band gap energy of titania. The retention of magnetic strength ensures controlled movement of the composite nanoparticles by the magnetic field, facilitating their application as removable anti-microbial photocatalyst nanoparticles. The consistent behavior of the composite nanoparticles points to the viability of the synthesis process adopted.

  • a comparative study of the gas sensing behavior of nanostructured Nickel Ferrite synthesized by hydrothermal and reverse micelle techniques
    Materials Research Bulletin, 2004
    Co-Authors: Madhusudan K Reddy, L Satyanarayana, Sunkara V Manorama, R D K Misra
    Abstract:

    Abstract A comparative study of gas sensing behavior of nanocrystalline Nickel Ferrite synthesized by micro-emulsion and hydrothermal method to liquefied petroleum gas (LPG) is presented. Nanocrystalline Nickel Ferrite synthesized by hydrothermal method indicated higher electrical conductivity and gas sensitivity at low operating temperature compared to nanocrystalline Nickel Ferrite synthesized by reverse micelle technique. This difference in the gas sensing behavior can be attributed to the presence of more oxygen vacancies (i.e. non-stoichiometry) in the hydrothermally synthesized Nickel Ferrite. Incorporation of palladium had a catalytic effect and the operating temperature was significantly reduced in both the samples. The higher operating temperature of the reverse micelle Nickel Ferrite material makes the sensor response speed faster (∼10 s) compared to the hydrothermally synthesized material (∼1 min).

  • magnetic behavior of nanocrystalline Nickel Ferrite synthesized by the reverse micelle technique
    Journal of Magnetism and Magnetic Materials, 2004
    Co-Authors: A Kale, S Gubbala, R D K Misra
    Abstract:

    Abstract Nanocrystalline Nickel Ferrite of crystallite size 5–8 nm, synthesized by the reverse micelle technique were characterized by high-resolution transmission electron microscopy and X-ray diffraction techniques, and the magnetic behavior studied by superconducting quantum interference device. Nanocrystalline Nickel Ferrite exhibit a blocking temperature of 16 K. They do not attain saturation magnetization even at a high field of 50 kOe. The lack of saturation in high field occurs in association with high field irreversibility and open loop at 50 kOe. The saturation magnetization at 300 K is 25.4 emu/g and at 2 K is 35.5 emu/g, which is significantly lower than that reported for the multidomain bulk Nickel Ferrite (55 emu/g). This is discussed in terms of a two-component nanoparticle system consisting of a spin glass-like surface layer of a few atomic layers thick and ferrimagnetically aligned core spins.

Yoonyoung Chang - One of the best experts on this subject based on the ideXlab platform.

  • process optimization and adsorption modeling of pb ii on Nickel Ferrite reduced graphene oxide nano composite
    Journal of Molecular Liquids, 2018
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Rama Rao Karri
    Abstract:

    Abstract The presence of toxic heavy metals such as Pb(II) in aqueous environments is causing adverse health risks to human beings, motivating researchers to develop efficient techniques to remove pollutants from potable and effluent water. Adsorption was found to be an efficient technique among the various pollutant removal techniques. Efficiency of the adsorption process depends on the adsorbent and its nature. In this regard, a synthesized Nickel Ferrite-reduced graphene oxide (NFRGO) nano-composite is developed and utilized as an adsorbent to remove heavy metal ions. Since the performance of the adsorption technique depends on independent process variables, the influence of parameters such as the initial solution concentration, adsorbent dosage, and contact residence time on the removal of Pb(II) by NFRGO using a batch adsorption process are systematically studied in this work. Based on the design of experiments approach and central composite design (CCD), twenty experimental runs are performed with each process variable segregated in the experimental range. The optimal values of the independent process variables to achieve maximum removal efficiency are examined using conventional response surface methodology (RSM). A quadratic model, which consists of a first-order and second-order degree regressive model is developed using the analysis of variance (ANOVA) and RSM - CCD framework. Based on the desirability index, the optimum values were found to be an initial concentration of 18.38 mg/L, an adsorbent dose of 0.55 g/L, and a contact residence time of 83 min in order to achieve 99% removal of Pb(II) ions with 0.953 desirability.

  • preparation and characterization of porous reduced graphene oxide based inverse spinel Nickel Ferrite nanocomposite for adsorption removal of radionuclides
    Journal of Hazardous Materials, 2017
    Co-Authors: Lakshmi Prasanna Lingamdinne, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang, Yoonyoung Chang
    Abstract:

    Abstract For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel Nickel Ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel Nickel Ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with Nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41 nm and 32.16 nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333 ± 2 K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity.

  • studies on removal of pb ii and cr iii using graphene oxide based inverse spinel Nickel Ferrite nano composite as sorbent
    Hydrometallurgy, 2016
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang
    Abstract:

    Abstract Synthesis of a hybrid graphene oxide based inverse spinel Nickel Ferrite (GONF) nano-composite material and subsequent utilization in heavy metal removal from aqueous solution is described in the present study. The synthesized GONF was characterized using X-ray diffraction (XRD), Fourier transform-infrared resonance (FT-IR), and X-ray photoelectron (XPS) spectroscopies. The morphology, the surface area and pore volume of GONF were evaluated by scanning electron microscopy (SEM) and BET analysis, respectively. GONF was successfully used for the removal of Pb(II) and Cr(III) by batch adsorption techniques. Batch kinetics studies revealed that the sorption of Pb(II) and Cr(III) onto GONF was well described by a pseudo-second-order equation. The sorption equilibrium data of Pb(II) and Cr(III) was well tuned to the Langmuir isotherm model than the Freundlich and Temkin isotherm models. Hence, the sorption of Pb(II) and Cr(III) onto GONF occurred through monolayer chemisorptions on the homogeneous surface of GONF. The pH sorption results suggest that the sorption occurs through a complexed mechanism. The sorption of metal ions increased with increasing temperature, which is evident for an endothermic chemisorption by inner -sphere surface complexation. The overall obtained results demonstrated the GONF as an effective sorbent for Pb(II) and Cr(III) removal from wastewater.

Lakshmi Prasanna Lingamdinne - One of the best experts on this subject based on the ideXlab platform.

  • process optimization and adsorption modeling of pb ii on Nickel Ferrite reduced graphene oxide nano composite
    Journal of Molecular Liquids, 2018
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Rama Rao Karri
    Abstract:

    Abstract The presence of toxic heavy metals such as Pb(II) in aqueous environments is causing adverse health risks to human beings, motivating researchers to develop efficient techniques to remove pollutants from potable and effluent water. Adsorption was found to be an efficient technique among the various pollutant removal techniques. Efficiency of the adsorption process depends on the adsorbent and its nature. In this regard, a synthesized Nickel Ferrite-reduced graphene oxide (NFRGO) nano-composite is developed and utilized as an adsorbent to remove heavy metal ions. Since the performance of the adsorption technique depends on independent process variables, the influence of parameters such as the initial solution concentration, adsorbent dosage, and contact residence time on the removal of Pb(II) by NFRGO using a batch adsorption process are systematically studied in this work. Based on the design of experiments approach and central composite design (CCD), twenty experimental runs are performed with each process variable segregated in the experimental range. The optimal values of the independent process variables to achieve maximum removal efficiency are examined using conventional response surface methodology (RSM). A quadratic model, which consists of a first-order and second-order degree regressive model is developed using the analysis of variance (ANOVA) and RSM - CCD framework. Based on the desirability index, the optimum values were found to be an initial concentration of 18.38 mg/L, an adsorbent dose of 0.55 g/L, and a contact residence time of 83 min in order to achieve 99% removal of Pb(II) ions with 0.953 desirability.

  • preparation and characterization of porous reduced graphene oxide based inverse spinel Nickel Ferrite nanocomposite for adsorption removal of radionuclides
    Journal of Hazardous Materials, 2017
    Co-Authors: Lakshmi Prasanna Lingamdinne, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang, Yoonyoung Chang
    Abstract:

    Abstract For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel Nickel Ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel Nickel Ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with Nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41 nm and 32.16 nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333 ± 2 K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity.

  • studies on removal of pb ii and cr iii using graphene oxide based inverse spinel Nickel Ferrite nano composite as sorbent
    Hydrometallurgy, 2016
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang
    Abstract:

    Abstract Synthesis of a hybrid graphene oxide based inverse spinel Nickel Ferrite (GONF) nano-composite material and subsequent utilization in heavy metal removal from aqueous solution is described in the present study. The synthesized GONF was characterized using X-ray diffraction (XRD), Fourier transform-infrared resonance (FT-IR), and X-ray photoelectron (XPS) spectroscopies. The morphology, the surface area and pore volume of GONF were evaluated by scanning electron microscopy (SEM) and BET analysis, respectively. GONF was successfully used for the removal of Pb(II) and Cr(III) by batch adsorption techniques. Batch kinetics studies revealed that the sorption of Pb(II) and Cr(III) onto GONF was well described by a pseudo-second-order equation. The sorption equilibrium data of Pb(II) and Cr(III) was well tuned to the Langmuir isotherm model than the Freundlich and Temkin isotherm models. Hence, the sorption of Pb(II) and Cr(III) onto GONF occurred through monolayer chemisorptions on the homogeneous surface of GONF. The pH sorption results suggest that the sorption occurs through a complexed mechanism. The sorption of metal ions increased with increasing temperature, which is evident for an endothermic chemisorption by inner -sphere surface complexation. The overall obtained results demonstrated the GONF as an effective sorbent for Pb(II) and Cr(III) removal from wastewater.

Jaekyu Yang - One of the best experts on this subject based on the ideXlab platform.

  • preparation and characterization of porous reduced graphene oxide based inverse spinel Nickel Ferrite nanocomposite for adsorption removal of radionuclides
    Journal of Hazardous Materials, 2017
    Co-Authors: Lakshmi Prasanna Lingamdinne, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang, Yoonyoung Chang
    Abstract:

    Abstract For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel Nickel Ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel Nickel Ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with Nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41 nm and 32.16 nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333 ± 2 K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity.

  • studies on removal of pb ii and cr iii using graphene oxide based inverse spinel Nickel Ferrite nano composite as sorbent
    Hydrometallurgy, 2016
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang
    Abstract:

    Abstract Synthesis of a hybrid graphene oxide based inverse spinel Nickel Ferrite (GONF) nano-composite material and subsequent utilization in heavy metal removal from aqueous solution is described in the present study. The synthesized GONF was characterized using X-ray diffraction (XRD), Fourier transform-infrared resonance (FT-IR), and X-ray photoelectron (XPS) spectroscopies. The morphology, the surface area and pore volume of GONF were evaluated by scanning electron microscopy (SEM) and BET analysis, respectively. GONF was successfully used for the removal of Pb(II) and Cr(III) by batch adsorption techniques. Batch kinetics studies revealed that the sorption of Pb(II) and Cr(III) onto GONF was well described by a pseudo-second-order equation. The sorption equilibrium data of Pb(II) and Cr(III) was well tuned to the Langmuir isotherm model than the Freundlich and Temkin isotherm models. Hence, the sorption of Pb(II) and Cr(III) onto GONF occurred through monolayer chemisorptions on the homogeneous surface of GONF. The pH sorption results suggest that the sorption occurs through a complexed mechanism. The sorption of metal ions increased with increasing temperature, which is evident for an endothermic chemisorption by inner -sphere surface complexation. The overall obtained results demonstrated the GONF as an effective sorbent for Pb(II) and Cr(III) removal from wastewater.

Janardhan Reddy Koduru - One of the best experts on this subject based on the ideXlab platform.

  • process optimization and adsorption modeling of pb ii on Nickel Ferrite reduced graphene oxide nano composite
    Journal of Molecular Liquids, 2018
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Rama Rao Karri
    Abstract:

    Abstract The presence of toxic heavy metals such as Pb(II) in aqueous environments is causing adverse health risks to human beings, motivating researchers to develop efficient techniques to remove pollutants from potable and effluent water. Adsorption was found to be an efficient technique among the various pollutant removal techniques. Efficiency of the adsorption process depends on the adsorbent and its nature. In this regard, a synthesized Nickel Ferrite-reduced graphene oxide (NFRGO) nano-composite is developed and utilized as an adsorbent to remove heavy metal ions. Since the performance of the adsorption technique depends on independent process variables, the influence of parameters such as the initial solution concentration, adsorbent dosage, and contact residence time on the removal of Pb(II) by NFRGO using a batch adsorption process are systematically studied in this work. Based on the design of experiments approach and central composite design (CCD), twenty experimental runs are performed with each process variable segregated in the experimental range. The optimal values of the independent process variables to achieve maximum removal efficiency are examined using conventional response surface methodology (RSM). A quadratic model, which consists of a first-order and second-order degree regressive model is developed using the analysis of variance (ANOVA) and RSM - CCD framework. Based on the desirability index, the optimum values were found to be an initial concentration of 18.38 mg/L, an adsorbent dose of 0.55 g/L, and a contact residence time of 83 min in order to achieve 99% removal of Pb(II) ions with 0.953 desirability.

  • preparation and characterization of porous reduced graphene oxide based inverse spinel Nickel Ferrite nanocomposite for adsorption removal of radionuclides
    Journal of Hazardous Materials, 2017
    Co-Authors: Lakshmi Prasanna Lingamdinne, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang, Yoonyoung Chang
    Abstract:

    Abstract For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel Nickel Ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel Nickel Ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with Nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41 nm and 32.16 nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333 ± 2 K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity.

  • studies on removal of pb ii and cr iii using graphene oxide based inverse spinel Nickel Ferrite nano composite as sorbent
    Hydrometallurgy, 2016
    Co-Authors: Lakshmi Prasanna Lingamdinne, Yoonyoung Chang, Janardhan Reddy Koduru, Yulim Choi, Jaekyu Yang
    Abstract:

    Abstract Synthesis of a hybrid graphene oxide based inverse spinel Nickel Ferrite (GONF) nano-composite material and subsequent utilization in heavy metal removal from aqueous solution is described in the present study. The synthesized GONF was characterized using X-ray diffraction (XRD), Fourier transform-infrared resonance (FT-IR), and X-ray photoelectron (XPS) spectroscopies. The morphology, the surface area and pore volume of GONF were evaluated by scanning electron microscopy (SEM) and BET analysis, respectively. GONF was successfully used for the removal of Pb(II) and Cr(III) by batch adsorption techniques. Batch kinetics studies revealed that the sorption of Pb(II) and Cr(III) onto GONF was well described by a pseudo-second-order equation. The sorption equilibrium data of Pb(II) and Cr(III) was well tuned to the Langmuir isotherm model than the Freundlich and Temkin isotherm models. Hence, the sorption of Pb(II) and Cr(III) onto GONF occurred through monolayer chemisorptions on the homogeneous surface of GONF. The pH sorption results suggest that the sorption occurs through a complexed mechanism. The sorption of metal ions increased with increasing temperature, which is evident for an endothermic chemisorption by inner -sphere surface complexation. The overall obtained results demonstrated the GONF as an effective sorbent for Pb(II) and Cr(III) removal from wastewater.