312 research outputs found

    Critical dynamics of diluted relaxational models coupled to a conserved density (diluted model C)

    Full text link
    We consider the influence of quenched disorder on the relaxational critical dynamics of a system characterized by a non-conserved order parameter coupled to the diffusive dynamics of a conserved scalar density (model C). Disorder leads to model A critical dynamics in the asymptotics, however it is the effective critical behavior which is often observed in experiments and in computer simulations and this is described by the full set of dynamical equations of diluted model C. Indeed different scenarios of effective critical behavior are predicted.Comment: 4 pages, 5 figure

    The Effect of Fused 12-Membered Nickel Metallacrowns on DNA and their Antibacterial Activity

    Get PDF
    The synthesis, characterization and the biological study of a series of Ni(ll)2(carboxylato)2 [12- MCNi(II)N(shi)2(pko)2-4][12-MCNi(ii)N(sh03(pko)-4] (CH3OH)3(H3O) fused 12-membered metallacrowns with 10 metal ions and commercial available herbicides or anti-inflammatory drugs as carboxylato ligands are reported. All the compounds have a mixed ligand composition with salicylhydroxamic acid and di-2-pyridylketonoxime as chelate agents. The compounds construct metallacrown cores {[12-MCNi(n)N(sj02(pko)2-4][12-MCNi(ll)N(shO3(pko)-4]}2+ following the pattern [-Ni-O-N-]4. The neutral decanuclear [Ni(II)(A)]2[12-MCNi(II)N(shi)2(pko)2-4][12-MCNi(II)N(pko)3(pko)-4] fused metallacrown, consists of two [12-MCM(ox)N(ligand)-4] units the {Ni(ll)(A)[12-MCNi(II)N(shi)2(pko)2-4]} and {Ni(II)(A)[12-MCNi(II)N(shi)3(pko)-4]} with 1+ and 1- charge, respectively. Each metallacrown unit has four ring Ni(II) ions and one additional encapsulated Ni(II) ion in planar arrangement. The anionic unit is bonded with cationic one creating binuclear moieties. The herbicide or antiiflammatory carboxylato ligands are bridging the central octahedral nickel atom with a ring metal ion in a bindetate fashion. The effect on DNA and their antibacterial activity was examined. The changes in the mobility can be attributed to the altered structures of the pDNA treated with Ni(II) complexes. Evaluating the data of the antibacterial activity of the compounds tested, we can conclude that nickel complexes present strong antibacterial activity

    Non-Markovian Dynamics of Charge Carriers in Quantum Dots

    Full text link
    We have investigated the dynamics of bound particles in multilevel current-carrying quantum dots. We look specifically in the regime of resonant tunnelling transport, where several channels are available for transport. Through a non-Markovian formalism under the Born approximation, we investigate the real-time evolution of the confined particles including transport-induced decoherence and relaxation. In the case of a coherent superposition between states with different particle number, we find that a Fock-space coherence may be preserved even in the presence of tunneling into and out of the dot. Real-time results are presented for various asymmetries of tunneling rates into different orbitals.Comment: 9 pages, 3 figures, International Workshop on Physics-Based Mathematical Models for Low-Dimensional Semiconductor Nanostructures. BIRS, November 18-23, 200

    Persistent Spin Currents in Helimagnets

    Full text link
    We demonstrate that weak external magnetic fields generate dissipationless spin currents in the ground state of systems with spiral magnetic order. Our conclusions are based on phenomenological considerations and on microscopic mean-field theory calculations for an illustrative toy model. We speculate on possible applications of this effect in spintronic devices.Comment: 9 pages, 6 figures, updated version as published, Journal referenc

    Singlet-triplet transition in a single-electron transistor at zero magnetic field

    Full text link
    We report sharp peaks in the differential conductance of a single-electron transistor (SET) at low temperature, for gate voltages at which charge fluctuations are suppressed. For odd numbers of electrons we observe the expected Kondo peak at zero bias. For even numbers of electrons we generally observe Kondo-like features corresponding to excited states. For the latter, the excitation energy often decreases with gate voltage until a new zero-bias Kondo peak results. We ascribe this behavior to a singlet-triplet transition in zero magnetic field driven by the change of shape of the potential that confines the electrons in the SET.Comment: 4 p., 4 fig., 5 new ref. Rewrote 1st paragr. on p. 4. Revised author list. More detailed fit results on page 3. A plotting error in the horizontal axis of Fig. 1b and 3 was corrected, and so were the numbers in the text read from those fig. Fig. 4 was modified with a better temperature calibration (changes are a few percent). The inset of this fig. was removed as it is unnecessary here. Added remarks in the conclusion. Typos are correcte

    Drivers of spatial change in urban housing submarkets

    Get PDF
    Spatial urban housing submarkets are now widely used constructs. Recent housing market modelling strategies have emphasised the need for flexibility in modelling approaches in order to best accommodate submarkets which account for spatial variations in hedonic prices. But this raises important unanswered questions concerning the stability of submarket structures over time, and the role of housing market dynamics in breaking down or shifting submarket boundaries. The influence of new supply, in particular, may have a stabilising or destabilising effect on differences in hedonic prices, depending on the wider housing market context. In this paper we examine the temporal influence of new supply, intra‐urban migration and socio‐economic change as a means of understanding the impact of key drivers of submarket boundary change. Using the Greater Perth region of Western Australia as a case study, we estimate income elasticities of demand for housing services that vary spatially within the urban area. We find evidence that higher income elasticities, new development, socio‐economic change and intra‐urban migration are associated with changes in the spatial structure of housing prices within the metropolitan housing market

    GEOMATICS AND CIVIL ENGINEERING INNOVATIVE RESEARCH ON HERITAGE: INTRODUCING THE “ENGINEER” PROJECT

    Get PDF
    This paper aims to introduce the concept and objectives of a recently supported European project entitled “Geomatics and Civil Engineering Innovative Research on Heritage”, in short ENGINEER. The ENGINEER project visions to enhance and extend inter-departmental multidisciplinary research activities of the Department of Civil Engineering & Geomatics of the Cyprus University of Technology through coordination and support actions as well as through targeted research activities with the support of European leading institutions. Project tasks aim to fill research multidisciplinary gaps, push, and extend knowledge into new and innovative fields dealing with the monitoring, digitization, visualization, and preservation of ancient monuments and cultural heritage sites, assisting their protection, promotion, and safeguarding
    corecore