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Arutiun Papken Ehiasarian - One of the best experts on this subject based on the ideXlab platform.

  • high power impulse magnetron sputtering hipims and traditional pulsed sputtering dcmsp ag surfaces leading to e coli inactivation
    2012
    Co-Authors: O. Baghriche, Ewelina Kusiaknejman, Antoni W. Morawski, Arutiun Papken Ehiasarian, Cesar Pulgarin, Rosendo Sanjines, John Kiwi
    Abstract:

    This study addresses the high power impulse magnetron sputtering (HIPIMS) deposition of Ag-nanoparticle films on polyester and the comparison with films deposited by direct current pulsed magnetron sputtering (DCMSP). The first evidence is presented for the Escherichia coli bacterial inactivation by HIPIMS sputtered polyester compared to Ag-polyester sputtered by DCMSP. HIPIMS layers were significantly thinner than the DCMSP sputtered layers needing a much lower Ag-loading to inactivate E. coil within the same time scale. The Ag-nanoparticle films sputtered by DCMSP at 300 mA for 160 s was observed to inactivate completely E. coil within 2 h having a content of 0.205% Ag wt%/polyester wt%. HIPIMS-sputtered at 5 A for 75 s led to complete E. colt bacterial inactivation also within 2 h having a content Ag 0.031% Ag wt%/polyester wt%. The atomic rate of deposition with DCMSP is 6.2 x 10(15) atoms Ag/cm(2) s while with HPIMS this rate was 2.7 x 10(15) atoms Ag/cm(2) s. The degree of ionization of Ag+/Ag2+ and Ar+/Ar2+ was proportional to the target current applied during HIPIMS-sputtering as determined by mass spectroscopy. These experiments reveal significant differences at the higher end of the currents applied during HIPIMS sputtering as illustrated by the ion-Flux Composition. X-ray photoelectron spectroscopy (XPS) was used to determine the surface atomic concentration of 0, Ag, and C on the Ag-polyester. These surface atomic concentrations were followed during the E. colt inactivation time providing the evidence for the E. coli oxidation on the Ag-polyester. X-ray diffraction shows Ag-metallic character for DCMSP sputtered samples for longer times compared to the Ag-clusters sputtered by HIPIMS leading to Ag-clusters aggregates. Ag-nanoparticle films on polyester sputtered by HIPIMS contain less Ag and are thinner compared to Ag-nanoparticle films sputtered by DCMSP. (C) 2011 Elsevier B.V. All rights reserved.

  • the ion energy distributions and ion Flux Composition from a high power impulse magnetron sputtering discharge
    2006
    Co-Authors: Johan Bohlmark, Arutiun Papken Ehiasarian, Martina Lattemann, Jon Tomas Gudmundsson, Aranda Y Gonzalvo, Nils Brenning, Ulf Helmersson
    Abstract:

    The energy distribution of sputtered and ionized metal atoms as well as ions from the sputtering gas is reported for a high power impulse magnetron sputtering (HIPIMS) discharge. High power pulses ...

John Kiwi - One of the best experts on this subject based on the ideXlab platform.

  • high power impulse magnetron sputtering hipims and traditional pulsed sputtering dcmsp ag surfaces leading to e coli inactivation
    2012
    Co-Authors: O. Baghriche, Ewelina Kusiaknejman, Antoni W. Morawski, Arutiun Papken Ehiasarian, Cesar Pulgarin, Rosendo Sanjines, John Kiwi
    Abstract:

    This study addresses the high power impulse magnetron sputtering (HIPIMS) deposition of Ag-nanoparticle films on polyester and the comparison with films deposited by direct current pulsed magnetron sputtering (DCMSP). The first evidence is presented for the Escherichia coli bacterial inactivation by HIPIMS sputtered polyester compared to Ag-polyester sputtered by DCMSP. HIPIMS layers were significantly thinner than the DCMSP sputtered layers needing a much lower Ag-loading to inactivate E. coil within the same time scale. The Ag-nanoparticle films sputtered by DCMSP at 300 mA for 160 s was observed to inactivate completely E. coil within 2 h having a content of 0.205% Ag wt%/polyester wt%. HIPIMS-sputtered at 5 A for 75 s led to complete E. colt bacterial inactivation also within 2 h having a content Ag 0.031% Ag wt%/polyester wt%. The atomic rate of deposition with DCMSP is 6.2 x 10(15) atoms Ag/cm(2) s while with HPIMS this rate was 2.7 x 10(15) atoms Ag/cm(2) s. The degree of ionization of Ag+/Ag2+ and Ar+/Ar2+ was proportional to the target current applied during HIPIMS-sputtering as determined by mass spectroscopy. These experiments reveal significant differences at the higher end of the currents applied during HIPIMS sputtering as illustrated by the ion-Flux Composition. X-ray photoelectron spectroscopy (XPS) was used to determine the surface atomic concentration of 0, Ag, and C on the Ag-polyester. These surface atomic concentrations were followed during the E. colt inactivation time providing the evidence for the E. coli oxidation on the Ag-polyester. X-ray diffraction shows Ag-metallic character for DCMSP sputtered samples for longer times compared to the Ag-clusters sputtered by HIPIMS leading to Ag-clusters aggregates. Ag-nanoparticle films on polyester sputtered by HIPIMS contain less Ag and are thinner compared to Ag-nanoparticle films sputtered by DCMSP. (C) 2011 Elsevier B.V. All rights reserved.

Feng Lin - One of the best experts on this subject based on the ideXlab platform.

Sujit Kumar Majumdar - One of the best experts on this subject based on the ideXlab platform.

  • combined effect of Flux and welding parameters on chemical Composition and mechanical properties of submerged arc weld metal
    2006
    Co-Authors: P Kanjilal, Tapan Kumar Pal, Sujit Kumar Majumdar
    Abstract:

    Abstract Rotatable designs based on statistical experiments for mixtures have been developed to predict the combined effect of Flux mixture and welding parameters on submerged arc weld metal chemical Composition and mechanical properties. Bead-on-plate weld deposits on low carbon steel plates were made at different Flux Composition and welding parameter combinations. The results show that Flux mixture related variables based on individual Flux ingredients and welding parameters have individual as well as interaction effects on responses, viz. weld metal chemical Composition and mechanical properties. In general, two factor interaction effect are higher than the individual effect of mixture related variables. Amongst welding parameters, polarity is found to be important for all responses under study.

Mercouri G Kanatzidis - One of the best experts on this subject based on the ideXlab platform.