41 research outputs found

    An experimental and theoretical study of transient negative ions in Mg, Zn, Cd and Hg

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    A range of experimental and theoretical techniques have been applied to the study of transient negative ions (resonances) formed in electron scattering from the Group II metals Mg, Zn, Cd, and Hg at incident electron energies below the first ionization potential. A wealth of resonance structures have been observed and from the experimental observations and theoretical information, classifications are proposed for some of these negative ion states

    HopScotch - a low-power renewable energy base station network for rural broadband access

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    The provision of adequate broadband access to communities in sparsely populated rural areas has in the past been severely restricted. In this paper, we present a wireless broadband access test bed running in the Scottish Highlands and Islands which is based on a relay network of low-power base stations. Base stations are powered by a combination of renewable sources creating a low cost and scalable solution suitable for community ownership. The use of the 5~GHz bands allows the network to offer large data rates and the testing of ultra high frequency ``white space'' bands allow expansive coverage whilst reducing the number of base stations or required transmission power. We argue that the reliance on renewable power and the intelligent use of frequency bands makes this approach an economic green radio technology which can address the problem of rural broadband access

    Ionization of Atoms with Spin Polarized Electrons

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    The most detailed insight into the process of electron impact-induced ionization of atomic species is provided by measurements in which both kinematical and quantum mechanical variables are determined. Here we describe recent (e,2e) experimental and theoretical studies involving the ionization of xenon and argon by spin-polarized electrons in which the fine-structure levels of the ion are energetically resolved. Such investigations shed light on the mechanisms driving the ionization reaction and the role of exchange and relativistic processes

    Recent Progress in Quantum-State Resolved Ionization Experiments

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    Photosynthetic reaction center/graphene bio-hybrid for low-power optoelectronics

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    Photosynthetic reaction center (pRC) purified from Rhodobacter sphaeroides 2.4.1 purple bacteria was deposited on a graphene carrier exfoliated from the liquid phase and layered on the surface of SiO2/Si substrate for optoelectronic application. Light-induced changes in the drain-source current vs. gate voltage are demonstrated. Dried photosynthetic reaction centers/graphene composite on SiO2/Si shows a photochemical/-physical activity, as a result of interaction with the current flow in the graphene carrier matrix. The current changes are sensitive to light, due to the contribution from the charge separation in the pRC, and to the applied gate and drain-source voltages

    Photosynthetic reaction center/graphene bio-hybrid for low-power optoelectronics

    No full text
    Photosynthetic reaction center (pRC) purified from Rhodobacter sphaeroides 2.4.1 purple bacteria was deposited on a graphene carrier exfoliated from the liquid phase and layered on the surface of SiO2/Si substrate for optoelectronic application. Light-induced changes in the drain-source current vs. gate voltage are demonstrated. Dried photosynthetic reaction centers/graphene composite on SiO2/Si shows a photochemical/-physical activity, as a result of interaction with the current flow in the graphene carrier matrix. The current changes are sensitive to light, due to the contribution from the charge separation in the pRC, and to the applied gate and drain-source voltages

    An experimental and theoretical study of transient negative ions in Mg, Zn, Cd and Hg

    Get PDF
    A range of experimental and theoretical techniques have been applied to the study of transient negative ions (resonances) formed in electron scattering from the Group II metals Mg, Zn, Cd, and Hg at incident electron energies below the first ionization potential. A wealth of resonance structures have been observed and from the experimental observations and theoretical information, classifications are proposed for some of these negative ion states

    Experimental and theoretical cross sections for elastic electron scattering from zinc

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    10 pags., 3 figs., 3 tabs.We report on experimental elastic differential and integral cross sections for electron scattering from zinc. The energy range of these measurements is 10-100 eV, while the scattered electron angular range in the differential cross-section data is 10°-150°. We also supplement our measured data with applications of our optical potential and relativistic optical potential approaches to this problem. Where possible, the present results are compared against those from earlier B-spline R-matrix [O. Zatsarinny and K. Bartschat, Phys. Rev. A 71, 022716 (2005)10.1103/PhysRevA.71.022716] and convergent close coupling [D. V. Fursa, I. Bray, R. Panajotović, D. Šević, V. Pejčev, D. M. Filipović, and B. P. Marinković, Phys. Rev. A 72, 012706 (2005)PLRAAN1050-294710.1103/PhysRevA.72.012706] computations. Good overall qualitative accord is typically observed.This work was financially supported, in part, by the Spanish Ministerio de Ciencia, Innovacion y Universidades (Project No. FIS2016-80440), the Australian Research Council (Projects No. DP160102787 and No. DP180101655), and the Ministry of Education, Science, and Technological Development(ProjectNo.OI171020)of the Republic of Serbia
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