Search Results - (Author, Cooperation:M. Bartkowiak)
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1S. R. Giblin, M. Twengström, L. Bovo, M. Ruminy, M. Bartkowiak, P. Manuel, J. C. Andresen, D. Prabhakaran, G. Balakrishnan, E. Pomjakushina, C. Paulsen, E. Lhotel, L. Keller, M. Frontzek, S. C. Capelli, O. Zaharko, P. A. McClarty, S. T. Bramwell, P. Henelius, and T. Fennell
American Physical Society (APS)
Published 2018Staff ViewPublication Date: 2018-08-08Publisher: American Physical Society (APS)Print ISSN: 0031-9007Electronic ISSN: 1079-7114Topics: PhysicsKeywords: Condensed Matter: Electronic Properties, etc.Published by: -
2M. Roffet-Salque ; M. Regert ; R. P. Evershed ; A. K. Outram ; L. J. Cramp ; O. Decavallas ; J. Dunne ; P. Gerbault ; S. Mileto ; S. Mirabaud ; M. Paakkonen ; J. Smyth ; L. Soberl ; H. L. Whelton ; A. Alday-Ruiz ; H. Asplund ; M. Bartkowiak ; E. Bayer-Niemeier ; L. Belhouchet ; F. Bernardini ; M. Budja ; G. Cooney ; M. Cubas ; E. M. Danaher ; M. Diniz ; L. Domboroczki ; C. Fabbri ; J. E. Gonzalez-Urquijo ; J. Guilaine ; S. Hachi ; B. N. Hartwell ; D. Hofmann ; I. Hohle ; J. J. Ibanez ; N. Karul ; F. Kherbouche ; J. Kiely ; K. Kotsakis ; F. Lueth ; J. P. Mallory ; C. Manen ; A. Marciniak ; B. Maurice-Chabard ; M. A. Mc Gonigle ; S. Mulazzani ; M. Ozdogan ; O. S. Peric ; S. R. Peric ; J. Petrasch ; A. M. Petrequin ; P. Petrequin ; U. Poensgen ; C. J. Pollard ; F. Poplin ; G. Radi ; P. Stadler ; H. Stauble ; N. Tasic ; D. Urem-Kotsou ; J. B. Vukovic ; F. Walsh ; A. Whittle ; S. Wolfram ; L. Zapata-Pena ; J. Zoughlami
Nature Publishing Group (NPG)
Published 2015Staff ViewPublication Date: 2015-11-13Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Africa, Northern ; Animals ; Archaeology ; Beekeeping/*history ; *Bees ; Ceramics/chemistry/history ; Europe ; Farmers/history ; Geographic Mapping ; History, Ancient ; Lipids/analysis/chemistry ; Middle East ; Spatio-Temporal Analysis ; Waxes/*analysis/chemistry/*historyPublished by: -
3Bartkowiak, M. ; Mahan, G. D. ; Modine, F. A. ; Alim, M. A. ; Lauf, R. ; McMillan, A.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Electrical transport in zinc oxide varistors is simulated using two-dimensional Voronoi networks. The networks are assumed to contain randomly distributed grain boundaries of three electrical types: (1) high nonlinearity (i.e., "good'') junctions; (2) poor nonlinearity (i.e., "bad'') junctions; and (3) linear with low-resistivity (i.e., ohmic) junctions. These type classifications are those found in experimental measurements. By varying the type concentrations, the simulated current density versus electric field (J–E) characteristics can be made to conform to the different experimentally observed characteristics of ZnO varistors. These characteristics include the sharpness of switching at the transition between ohmic and nonlinear J–E response (i.e., knee region), as well as the degree of nonlinearity. It is shown that the reduction of the nonlinearity coefficient of bulk varistors, relative to that of isolated grain boundaries, can be explained only by the presence of "bad'' varistor junctions. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
4Bartkowiak, M. ; Comber, M. G. ; Mahan, G. D.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Thermal and mechanical behavior of high power ZnO surge arresters under current pulses of various magnitude and duration is simulated. By solving heat transfer equations for a varistor disk with nonuniform electrical properties, we compute the time dependence of the temperature profile and the distribution of thermal stresses. The simulations identify failure processes and determine energy handling capability of varistor elements as a function of the applied current. The results are in good agreement with the experimental data and explain the energy handling dependence upon the surge intensity and duration. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
5Bartkowiak, M. ; Mahan, G. D. ; Modine, F. A. ; Alim, M. A.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: A realistic model of transport properties of zinc oxide varistors is constructed from two-dimensional Voronoi networks and studied via computer simulations. In agreement with experimental microcontact measurements made on individual junctions, the networks are assumed to contain randomly distributed microjunctions of two types: (1) electrically active with highly nonlinear current-voltage (I-V) characteristics and (2) ohmic, i.e., with linear I-V characteristics. Effects of the ohmic grain boundaries in the network are simulated for various concentrations and resistivities. Shapes of the simulated I-V characteristics and current dependence of the coefficient of nonlinearity of the network are in good agreement with those experimentally observed for thin varistor samples and in the measurements employing various surface electrode patterns. It is found that the breakdown voltage of the networks increases with the number of the ohmic grain boundaries, except when their resistivity is so low that it becomes comparable with that of the ZnO grains. The maximal value of the coefficient of nonlinearity of the network is shown to be insensitive to the presence of the ohmic grain boundaries, regardless of their resistivity and concentration. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
6Mahan, G. D. ; Sofo, J. O. ; Bartkowiak, M.
[S.l.] : American Institute of Physics (AIP)
Published 1998Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: A new method of refrigeration is proposed. Cooling is obtained by thermionic emission of electrons over periodic barriers in a multilayer geometry. These could be either Schottky barriers between metals and semiconductors or else barriers in a semiconductor superlattice. The same device is an efficient power generator. A complete theory is provided. © 1998 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
7Staff View
ISSN: 1077-3118Source: AIP Digital ArchiveTopics: PhysicsNotes: The full equations are derived for the resistances to the transport of heat and electricity through boundaries of thermoelectrics. We show that the boundary resistances of heat and electricity are proportional. This relationship is a boundary form of the Wiedemann–Franz law. We also show there is a boundary Seebeck coefficient. © 1999 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
8Staff View
ISSN: 0009-2614Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
9Staff View
ISSN: 0009-2614Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
10Staff View
ISSN: 0009-2614Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
11Staff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
12Staff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
13Staff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
14Staff View
ISSN: 0375-9601Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
15Staff View
ISSN: 1572-8943Keywords: diamond ; fullerene ; graphite ; heat capacity ; polyethylene ; poly(ethylene terephthalate) ; polypropylene ; selenium ; solid state ; Tarasov equation ; vibrational spectraSource: Springer Online Journal Archives 1860-2000Topics: Chemistry and PharmacologyNotes: Abstract The general Tarasov function is fitted to the skeletal heat capacities of materials with widely different crystal structures. Examples are chosen from flexible macromolecules (polyethylene, polypropylene, poly(ethylene terephthalate), selenium, rigid macromolecules (diamond and graphite), and a small molecule (fullerene, C60). A new optimization approach using the MathematicaTM software is developed. It results in one-, two-, and three-dimensional Debye temperatures, Θ1, Θ2 and Θ3 the fitting parameters of the Tarasov function. In addition to the Tarasov function, the evaluation of the heat capacities makes use of approximate group-vibrational spectra. The results support the earlier assumption that Θ2=Θ3 for simple, solid, linear macromolecules. In more complicated bonding situations, Θ1, Θ2 and Θ3 are used as averaging fitting parameters. This general approach provides an improvement in the quantitative thermal analyses of polymers and other substances included in the ATHAS Data Bank. Sufficient programming information is provided to enable anyone the computation with a copy of the popular MathematicaTM software. The programming file is also downloadable from the WWW.Type of Medium: Electronic ResourceURL: