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Suche nach „[2012]“ hat 123 Publikationen gefunden
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    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    Gerhard, R., Basso, H.C., R.A.C. Altafim, M. Melzer, Wirges, W., Dmitry Rychkov, Altafim, R.A.P.

    Laminated tubular-channel ferroelectret systems from low-density polyethylene films and from fluoroethylene-propylene copolymer films-A comparison

    IEEE Transactions on Dielectrics and Electrical Insulation, vol. 19, no. 4, pp. 1116-1123

    2012

    DOI: 10.1109/TDEI.2012.6259978

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    H. Stoyanov, McCarthy, D.N., M. Melzer, H. Ragusch, Dmitry Rychkov, G. Kofod

    Increased permittivity nanocomposite dielectrics by controlled interfacial interactions

    Composites Science and Technology, vol. 72, no. 6, pp. 731-736

    2012

    DOI: 10.1016/j.compscitech.2012.01.026

    Abstract anzeigen

    The use of nanoparticles in polymer composite dielectrics has promised great improvements, but useful results have been elusive. Here, the importance of the interfacial interactions between the nanoparticles and the polymer matrix are investigated in TiO2 nanocomposites for dielectric materials using surface functionalisation. The interface is observed to dominate the nanocomposite properties and leads to a threefold increase in permittivity at volume fractions as low as 10%. Surface functionalisation of the filler nanoparticles with silanes allows control of this interface, avoiding significant degradation of the other important material properties, particularly electrical breakdown strength, and resulting in a material that is demonstrated successfully as an active material in a dielectric elastomer actuator application with increased work output compared to the pure polymer. Although further permittivity increases are observed when the interface regions have formed a percolation network, the other material properties deteriorate. The observation of percolation behaviour allows the interface thickness to be estimated.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    Gerhard, R., Qiu, X., Dmitry Rychkov, Altafim, R.A.P.

    Treatment with orthophosphoric acid enhances the thermal stability of the piezoelectricity in low-density polyethylene ferroelectrets

    Journal of Applied Physics, vol. 111, no. 12

    2012

    DOI: 10.1063/1.4729866

    Abstract anzeigen

    Ferroelectrets have been fabricated from low-density polyethylene (LDPE) films by means of a template-based lamination. The temperature dependence of the piezoelectric d33 coefficient has been investigated. It was found that low-density polyethylene ferroelectrets have rather low thermal stability with the piezoelectric coefficient decaying almost to zero already at 100 °C. This behavior is attributed to the poor electret properties of the polyethylene films used for the fabrication of the ferroelectrets. In order to improve the charge trapping and the thermal stability of electret charge and piezoelectricity, LDPE ferroelectrets were treated with orthophosphoric acid. The treatment resulted in considerable improvements of the charge stability in LDPE films and in ferroelectret systems made from them. For example, the charge and piezoelectric-coefficient decay curves shifted to higher temperatures by 60 K and 40 K, respectively. It is shown that the decay of the piezoelectric coefficient in LDPE ferroelectrets is governed by the relaxation of less stable positive charges. The treatment also leads to noticeable changes in the chemical composition of the LDPE surface. Infrared spectroscopy reveals absorption bands attributed to phosphorus-containing structures, while scanning electron microscopy shows new island-like structures, 50–200 nm in diameter, on the modified surface.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    Gerhard, R., Ivanov, V., Dmitry Rychkov, Rychkov, A. A.

    Enhanced electret charge stability on polyethylene films treated with titanium-tetrachloride vapor

    IEEE Transactions on Dielectrics and Electrical Insulation, vol. 19, no. 4, pp. 1305-1311

    2012

    DOI: 10.1109/TDEI.2012.6260005

    Abstract anzeigen

    Low-density polyethylene (LDPE) films have been treated with titanium-tetrachloride vapor by means of the molecular-layer-deposition method. It is shown that such a treatment leads to a considerable improvement of the electret properties for both positively and negatively charged films. The temperature stability of the electret homo-charge has been increased by approximately 60°C. At the same time, the temporal stability of charge is also considerably improved. Modified low-density polyethylene films show no “cross-over phenomenon” when charged to higher voltages. Thus, it is now possible to produce electrets from polyethylene films with high initial charge densities, but without a strongly reduced charge stability. The influence of a chemical treatment with titanium-tetrachloride vapor on charge injection from aluminum electrodes into polyethylene films was also investigated. It is found that the interface between an aluminum electrode and a modified LDPE surface layer has different injection properties for positive and negative charges. Electrons can be injected across the modified interface, whereas injection of holes is either very limited or non-existent.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    Yablokov, M., Dmitry Rychkov, Rychkov, A. A.

    Chemical and physical surface modification of PTFE films—an approach to produce stable electrets

    Applied Physics A - Materials Science and Processing, vol. 107, no. 3, pp. 589-596

    2012

    DOI: 10.1007/s00339-012-6834-5

    Abstract anzeigen

    The thermal stability of positive charge has been investigated in chemically and physically treated polytetrafluoroethylene (PTFE) films. It has been found that virgin films, oriented by the manufacturer, display an increase in thermal stability of positive charge with an increase of the initial value of surface potential. Such an anomalous behavior is explained by the influence of a negative tribocharge, trapped some small distance below the surface. In PTFE samples treated with orthophosphoric acid and with tetraethoxysilane, a considerable improvement of positive charge stability has been achieved, but no influence of the initial value of surface potential has been observed. However, this influence should be kept in mind when comparing charge stability in virgin and modified samples. In nonoriented PTFE films, no influence of the initial value of surface potential on charge stability has been observed. This could be due to the fact that these films did not possess a noticeable negative tribocharge. After the treatment in glow-discharge defluorination, oxidation and appearance of polar groups have been detected on the surface. These changes in chemical composition of a PTFE surface resulted in a noticeable improvement in thermal stability of positively charged electrets. This improvement is attributed to the formation of deeper traps on the modified surface.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Patent

    Dmitry Rychkov, Rychkov, A. A., Dergachev, V.F., et al.

    Method of film electret production, involves applying fluoropolymer layer on metal electrode surface with electreting and applying discrete layer on fluoropolymer surface with nanosized aggregates of titan-containing nanostructures

    2012

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Bestimmung des Bewegungsverhaltens eines Kraftstoffinjektors basierend auf dem zeitlichen Abstand zwischen den ersten beiden Spannungspulsen in einer Haltephase

    2012

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Bestimmung des Bewegungsverhaltens eines Kraftstoffinjektors basierend auf dem zeitlichen Abstand zwischen den ersten beiden Spannungsimpulsen in einer Haltephase [EN] Determination of the movement ...

    2012

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Bestimmung des Standardserien-Öffnungsverhaltens eines Kraftstoffinjektors basierend auf einem Test-Öffnungsverhalten unter dem Einfluss eines Testpulses mit konstanter Spannung [EN] Determination ...

    2012

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Bestimmung des Standardserien-Öffnungsverhaltens eines Kraftstoffinjektors basierend auf einem Test-Öffnungsverhalten unter dem Einfluss eines Testpulses mit konstanter Spannung

    2012

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Charakterisierung einer Bewegung eines Kraftstoffinjektors mittels Erfassung und Auswertung einer magnetischen Hysteresekurve [EN] Method for determining time point of beginning of movement of ...

    2012

    TC Cham

    Patent

    Continental Automotive GmbH, M. Glötzl, Frank Denk

    Method for determining winding temperature of magnetic coil of injector for injecting fuel into internal combustion engine, involves supplying injector with current during injection process, and determining internal resistor of injector

    2012

    DigitalMaschinenbau und Mechatronik

    Zeitschriftenartikel

    Jochen Hiller, L. Reindl

    A computer simulation platform for the estimation of measurement uncertainties in dimensional X-ray computed tomography

    Measurement, vol. 45, no. 8, pp. 2166-2182

    2012

    DOI: 10.1016/j.measurement.2012.05.030

    GesundAngewandte Gesundheitswissenschaften

    Zeitschriftenartikel

    S. Kuphal, L. Vardimon, Melanie Kappelmann-Fenzl, S. Meierjohann, B. Spangler, B. Schittek, A. Bosserhoff

    ETS‐1/RhoC signaling regulates the transcription factor c‐Jun in melanoma

    International Journal of Cancer, vol. 130, no. 12, pp. 2801-2811

    2012

    DOI: 10.1002/ijc.26277

    Abstract anzeigen

    Recently, we discovered that the loss of E‐cadherin induces c‐Jun protein expression, which is a member of the AP‐1 transcription factor family and a key player in the processes of cell proliferation and tumor development and also found in elevated levels in melanomas. Notably, the mRNA level of c‐Jun was not affected, suggesting that c‐Jun is regulated at post‐transcriptional level. Here, we present data that suggest that the dynamic cytoskeletal network, linked to E‐cadherin, is involved in the regulation of the c‐Jun protein and transcriptional activity. In a signaling cascade, the loss of E‐cadherin activates the transcriptional regulator ETS‐1 and consequently leads to the induction of RhoC expression that stabilizes c‐Jun in melanoma. The link between RhoC and c‐Jun seems to be indirect via the cytoskeleton. We conclude that the loss of E‐cadherin mediated cell‐adhesion induces c‐Jun protein expression in a multistep process, offering several possibilities for therapeutic intervention.

    MobilEuropan Campus Rottal-Inn

    Georg Steckenbauer

    Ergebnisse Evaluierung touristischer Aspekte von E-Mobilität Niederösterreich

    Forschungsbericht

    2012

    NachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    A. Milosavljević, M. Mátéfi-Tempfli, K. Schiessl, J. Burgdörfer, C. Lemell, B. Marinković, Stefan Mátéfi-Tempfli, K. Tökési

    Charging dynamics in electron transmission through Al2O3 capillaries

    Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, vol. 279, pp. 190-193

    2012

    Abstract anzeigen

    We have measured the transmission of low-energy electrons through insulating Al2O3 nanocapillaries. We find that transmission at the incident energy is quickly suppressed with increasing tilt angle of the capillary axis relative to the incoming electron beam while inelastic transmission becomes more important. For small angles of incidence charging dynamics lead to a decrease of total transmission (elastic and inelastic) with time. Our results are interpreted on the basis of a microscopic model for the electron transport within the capillary including also close interactions with the capillary wall.

    DigitalGesundEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    Georgi Chaltikyan, D. Gasparyan, R. Hovhannisyan, A. Haroyan, A. Avoyan, T. Saghatelyan

    Outcomes of the First Armenian International Congress on Telemedicine and eHealth "ARMTELEMED: Road to the Future" (October 14-16, 2011; Yerevan, Armenia)

    Telemedicine Journal and e-Health : The Official Journal of the American Telemedicine Association, vol. 18, no. 5, pp. 400-402

    2012

    DOI: 10.1089/tmj.2012.9993

    GesundAngewandte GesundheitswissenschaftenEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    Irmgard Tischner, H. Malson

    Deconstructing health and the un/healthy ‘fat’ woman

    Journal of Community & Applied Social Psychology, vol. 22, no. 1, pp. 50-62

    2012

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Zeitschriftenartikel

    D. Walcyk, T. Blomberg, Günther Ruhl, M. Lukosius, C. Wenger

    Metal-Insulator-Metal capacitors with ALD grown SrTiO3: Influence of Pt electrodes

    IOP Conference Series: Materials Science and Engineering, vol. 41

    2012

    Abstract anzeigen

    Metal-Insulator-metal (MIM) capacitors with atomic layer deposited (ALD) single SrTiO3 dielectric have been investigated in this work. Structural and electrical properties were studied after the formation of the MIM stack consisting of the platinum (Pt) bottom electrode, 50 nm SrTiO3 layer and the top Pt electrode. The as deposited films were amorphous and had a dielectric constant of ~ 10, whereas the annealing of the samples in the nitrogen (N2) or oxygen (O2) atmosphere at 550-600 °C led to the crystallization of the SrTiO3 and therefore to the increased dielectric constant of ~ 85. In addition, the electrical results revealed that the combination of SrTiO3 with the high work function electrode like Pt, provided better leakage current performance in comparison with TiN/ SrTiO3 stacks. The values as low as ~ 10−7 A/cm2 at 2 V were observed for both in N2 or O2 annealed SrTiO3 layers. On the other hand, the samples annealed in O2 atmosphere at 600 °C possessed lower capacitance-voltage nonlinearity coefficients (−645 ppm/V2) than the ones for N2 annealed samples (-2700 ppm/V2).