WorldWideScience

Sample records for two-center two-electron hybrid

  1. Evaluation of Two-center One- and Two-electron Integrals over Slater Type Orbitals

    Institute of Scientific and Technical Information of China (English)

    YAKAR Yusuf; (O)ZMEN Ayhan; ATAV (U)lfet

    2006-01-01

    A formulation previously presented by the authors for coulomb integrals was generalized to other two-center integrals, except exchange integral. Within this frame, molecular integrals were expressed in terms of some new functions closely related to the well-known incomplete gamma functions and these functions recursively evaluated.Special issues arising in the case of hybrid integrals were addressed, and the results were compared with the ones found in the literature.

  2. Evaluation of two-center Coulomb and hybrid integrals over complete orthonormal sets of Ψα-ETO using auxiliary functions.

    Science.gov (United States)

    Guseinov, Israfil I; Sahin, Ercan

    2011-04-01

    By the use of ellipsoidal coordinates, the two-center Coulomb and hybrid integrals over complete orthonormal sets of Ψα-ETO exponential type orbitals arising in ab initio calculations of molecules are evaluated, where α = 1,0, -1, -2, ...,. These integrals are expressed through the auxiliary functions Q(ns)(q) and G(-ns)(q). The comparison is made with some values of integrals for Slater type orbitals the computation results of which are in good agreement with those obtained in the literature. The relationships obtained are valid for the arbitrary quantum numbers, screening constants and location of orbitals. Closed form expressions for two-center Coulomb and hybrid integrals for 1s and 2s orbitals with α = 1 are also presented. As an example of application, the Hartree-Fock-Roothaan calculations for the ground state of H(2) molecule are carried out with α = 1 and α = 0.

  3. Benchmark values for molecular two-electron integrals arising from the Dirac equation

    Science.gov (United States)

    Baǧcı, A.; Hoggan, P. E.

    2015-02-01

    The two-center two-electron Coulomb and hybrid integrals arising in relativistic and nonrelativistic ab initio calculations on molecules are evaluated. Compact, arbitrarily accurate expressions are obtained. They are expressed through molecular auxiliary functions and evaluated with the numerical Global-adaptive method for arbitrary values of parameters in the noninteger Slater-type orbitals. Highly accurate benchmark values are presented for these integrals. The convergence properties of new molecular auxiliary functions are investigated. The comparison for two-center two-electron integrals is made with results obtained from single center expansions by translation of the wave function to a single center with integer principal quantum numbers and results obtained from the Cuba numerical integration algorithm, respectively. The procedures discussed in this work are capable of yielding highly accurate two-center two-electron integrals for all ranges of orbital parameters.

  4. Benchmark values for molecular two-electron integrals arising from the Dirac equation.

    Science.gov (United States)

    Bağcı, A; Hoggan, P E

    2015-02-01

    The two-center two-electron Coulomb and hybrid integrals arising in relativistic and nonrelativistic ab initio calculations on molecules are evaluated. Compact, arbitrarily accurate expressions are obtained. They are expressed through molecular auxiliary functions and evaluated with the numerical Global-adaptive method for arbitrary values of parameters in the noninteger Slater-type orbitals. Highly accurate benchmark values are presented for these integrals. The convergence properties of new molecular auxiliary functions are investigated. The comparison for two-center two-electron integrals is made with results obtained from single center expansions by translation of the wave function to a single center with integer principal quantum numbers and results obtained from the Cuba numerical integration algorithm, respectively. The procedures discussed in this work are capable of yielding highly accurate two-center two-electron integrals for all ranges of orbital parameters.

  5. Calculation of two-centre two-electron integrals over Slater-type orbitals revisited. I. Coulomb and hybrid integrals

    CERN Document Server

    Lesiuk, Michał

    2014-01-01

    In this paper, which constitutes the first part of the series, we consider calculation of two-centre Coulomb and hybrid integrals over Slater-type orbitals (STOs). General formulae for these integrals are derived with no restrictions on the values of the quantum numbers and nonlinear parameters. Direct integration over the coordinates of one of the electrons leaves us with the set of overlap-like integrals which are evaluated by using two distinct methods. The first one is based on the transformation to the ellipsoidal coordinates system and the second utilises a recursive scheme for consecutive increase of the angular momenta in the integrand. In both methods simple one-dimensional numerical integrations are used in order to avoid severe digital erosion connected with the straightforward use of the alternative analytical formulae. It is discussed that the numerical integration does not introduce a large computational overhead since the integrands are well-behaved functions, calculated recursively with decent...

  6. Numerical evaluation of two-center integrals over Slater type orbitals

    Science.gov (United States)

    Kurt, S. A.; Yükçü, N.

    2016-03-01

    Slater Type Orbitals (STOs) which one of the types of exponential type orbitals (ETOs) are used usually as basis functions in the multicenter molecular integrals to better understand physical and chemical properties of matter. In this work, we develop algorithms for two-center overlap and two-center two-electron hybrid and Coulomb integrals which are calculated with help of translation method for STOs and some auxiliary functions by V. Magnasco's group. We use Mathematica programming language to produce algorithms for these calculations. Numerical results for some quantum numbers are presented in the tables. Consequently, we compare our obtained numerical results with the other known literature results and other details of evaluation method are discussed.

  7. Deformed two center shell model

    CERN Document Server

    Gherghescu, R A

    2003-01-01

    A highly specialized two-center shell model has been developed accounting for the splitting of a deformed parent nucleus into two ellipsoidaly deformed fragments. The potential is based on deformed oscillator wells in direct correspondance with the shape change of the nuclear system. For the first time a potential responsible for the necking part between the fragments is introduced on potential theory basis. As a direct consequence, spin-orbit {\\bf ls} and {\\bf l$^2$} operators are calculated as shape dependent. Level scheme evolution along the fission path for pairs of ellipsoidaly deformed fragments is calculated. The Strutinsky method yields the shell corrections for different mass asymmetries from the superheavy nucleus $^{306}$122 and $^{252}$Cf all along the splitting process.

  8. Two-Centered Magical Charge Orbits

    CERN Document Server

    Andrianopoli, Laura; Ferrara, Sergio; Marrani, Alessio; Trigiante, Mario

    2011-01-01

    We determine the two-centered generic charge orbits of magical N = 2 and maximal N = 8 supergravity theories in four dimensions. These orbits are classified by seven U-duality invariant polynomials, which group together into four invariants under the horizontal symmetry group SL(2,R). These latter are expected to disentangle different physical properties of the two-centered black-hole system. The invariant with the lowest degree in charges is the symplectic product (Q1,Q2), known to control the mutual non-locality of the two centers.

  9. Two-Electron Transfer Pathways.

    Science.gov (United States)

    Lin, Jiaxing; Balamurugan, D; Zhang, Peng; Skourtis, Spiros S; Beratan, David N

    2015-06-18

    The frontiers of electron-transfer chemistry demand that we develop theoretical frameworks to describe the delivery of multiple electrons, atoms, and ions in molecular systems. When electrons move over long distances through high barriers, where the probability for thermal population of oxidized or reduced bridge-localized states is very small, the electrons will tunnel from the donor (D) to acceptor (A), facilitated by bridge-mediated superexchange interactions. If the stable donor and acceptor redox states on D and A differ by two electrons, it is possible that the electrons will propagate coherently from D to A. While structure-function relations for single-electron superexchange in molecules are well established, strategies to manipulate the coherent flow of multiple electrons are largely unknown. In contrast to one-electron superexchange, two-electron superexchange involves both one- and two-electron virtual intermediate states, the number of virtual intermediates increases very rapidly with system size, and multiple classes of pathways interfere with one another. In the study described here, we developed simple superexchange models for two-electron transfer. We explored how the bridge structure and energetics influence multielectron superexchange, and we compared two-electron superexchange interactions to single-electron superexchange. Multielectron superexchange introduces interference between singly and doubly oxidized (or reduced) bridge virtual states, so that even simple linear donor-bridge-acceptor systems have pathway topologies that resemble those seen for one-electron superexchange through bridges with multiple parallel pathways. The simple model systems studied here exhibit a richness that is amenable to experimental exploration by manipulating the multiple pathways, pathway crosstalk, and changes in the number of donor and acceptor species. The features that emerge from these studies may assist in developing new strategies to deliver multiple

  10. Resonances in the two centers Coulomb system

    Energy Technology Data Exchange (ETDEWEB)

    Seri, Marcello

    2012-09-14

    In this work we investigate the existence of resonances for two-centers Coulomb systems with arbitrary charges in two and three dimensions, defining them in terms of generalized complex eigenvalues of a non-selfadjoint deformation of the two-center Schroedinger operator. After giving a description of the bifurcation of the classical system for positive energies, we construct the resolvent kernel of the operators and we prove that they can be extended analytically to the second Riemann sheet. The resonances are then defined and studied with numerical methods and perturbation theory.

  11. Covering and piercing disks with two centers

    KAUST Repository

    Ahn, Heekap

    2013-04-01

    We give exact and approximation algorithms for two-center problems when the input is a set D of disks in the plane. We first study the problem of finding two smallest congruent disks such that each disk in D intersects one of these two disks. Then we study the problem of covering the set D by two smallest congruent disks. © 2012 Elsevier B.V.

  12. Covering and piercing disks with two centers

    KAUST Repository

    Ahn, Heekap

    2011-01-01

    We consider new versions of the two-center problem where the input consists of a set D of disks in the plane. We first study the problem of finding two smallest congruent disks such that each disk in intersects one of these two disks. Then we study the problem of covering the set D by two smallest congruent disks. We give exact and approximation algorithms for these versions. © 2011 Springer-Verlag.

  13. Angular momentum sensitive two-center interference.

    Science.gov (United States)

    Ilchen, M; Glaser, L; Scholz, F; Walter, P; Deinert, S; Rothkirch, A; Seltmann, J; Viefhaus, J; Decleva, P; Langer, B; Knie, A; Ehresmann, A; Al-Dossary, O M; Braune, M; Hartmann, G; Meissner, A; Tribedi, L C; AlKhaldi, M; Becker, U

    2014-01-17

    In quantum mechanics the Young-type double-slit experiment can be performed with electrons either traveling through a double slit or being coherently emitted from two inversion symmetric molecular sites. In the latter one the valence photoionization cross sections of homonuclear diatomic molecules were predicted to oscillate over kinetic energy almost 50 years ago. Beyond the direct proof of the oscillatory behavior of these photoionization cross sections σ, we show that the angular distribution of the emitted electrons reveals hitherto unexplored information on the relative phase shift between the corresponding partial waves through two-center interference patterns.

  14. Angular Momentum Sensitive Two-Center Interference

    Science.gov (United States)

    Ilchen, M.; Glaser, L.; Scholz, F.; Walter, P.; Deinert, S.; Rothkirch, A.; Seltmann, J.; Viefhaus, J.; Decleva, P.; Langer, B.; Knie, A.; Ehresmann, A.; Al-Dossary, O. M.; Braune, M.; Hartmann, G.; Meissner, A.; Tribedi, L. C.; AlKhaldi, M.; Becker, U.

    2014-01-01

    In quantum mechanics the Young-type double-slit experiment can be performed with electrons either traveling through a double slit or being coherently emitted from two inversion symmetric molecular sites. In the latter one the valence photoionization cross sections of homonuclear diatomic molecules were predicted to oscillate over kinetic energy almost 50 years ago. Beyond the direct proof of the oscillatory behavior of these photoionization cross sections σ, we show that the angular distribution of the emitted electrons reveals hitherto unexplored information on the relative phase shift between the corresponding partial waves through two-center interference patterns.

  15. Gravitational force between two electrons in superconductors

    CERN Document Server

    de Matos, Clovis Jacinto

    2007-01-01

    The attractive gravitational force between two electrons in superconductors is deduced from the Eddington-Dirac large number relation, together with Beck and Mackey electromagnetic model of vacuum energy in superconductors. This force is estimated to be weaker than the gravitational attraction between two electrons in the vacuum.

  16. Two-electron photoionization of endohedral atoms

    CERN Document Server

    Amusia, M Ya; Mandelzweig, V B

    2006-01-01

    Using $He@C_{60}$ as an example, we demonstrate that static potential of the fullerene core essentially alters the cross section of the two-electron ionization differential in one-electron energy $d\\sigma ^{++}(\\omega )/d\\epsilon $. We found that at high photon energy prominent oscillations appear in it due to reflection of the second, slow electron wave on the $% C_{60}$ shell, which "dies out" at relatively high $\\epsilon $ values, of about 2$\\div $3 two-electron ionization potentials. The results were presented for ratios $R_{C_{60}}(\\omega ,\\epsilon)\\equiv d\\sigma ^{++}(\\omega ,\\epsilon)/d\\sigma ^{a++}(\\omega,\\epsilon)$, where $d\\sigma ^{a++}(\\omega,\\epsilon)/d\\epsilon$ is the two-electron differential photoionization cross section. We have calculated the ratio $R_{i,ful}= \\sigma_{i} ^{++}(\\omega)/\\sigma_{i}^{a++}(\\omega)$, that accounts for reflection of both photoelectrons by the $C_{60}$ shell. We have calculated also the value of two-electron photoionization cross section $\\sigma ^{++}(\\omega)$ and fo...

  17. Two-Center Black Holes, Qubits and Elliptic Curves

    CERN Document Server

    Lévay, Péter

    2011-01-01

    We relate the U-duality invariants characterizing two-center extremal black hole solutions in the stu, st^2 and t^3 models of N=2, d=4 supergravity to the basic invariants used to characterize entanglement classes of four-qubit systems. For the elementary example of a D0D4-D2D6 composite in the t^3 model we illustrate how these entanglement invariants are related to some of the physical properties of the two-center solution. Next we show that it is possible to associate elliptic curves to charge configurations of two-center composites. The hyperdeterminant of the hypercube, a four-qubit polynomial invariant of order 24 with 2894276 terms, is featuring the j invariant of the elliptic curve. We present some evidence that this quantity and its straightforward generalization should play an important role in the physics of two-center solutions.

  18. Double ionization of two-electron systems

    Energy Technology Data Exchange (ETDEWEB)

    Ancarani, L U; Cappello, C Dal [Laboratoire de Physique Moleculaire et des Collisions, Universite Paul Verlaine - Metz, 57078 Metz (France); Gasaneo, G, E-mail: ancarani@univ-metz.f [Departamento de Fisica, Universidad Nacional del Sur and Consejo Nacional de Investigaciones CientIficas y Tecnicas, 8000 BahIa Blanca, Buenos Aires (Argentina)

    2010-02-01

    We address various issues related to the double ionization by electron impact of two-electron systems. The emphasis will be put on the theoretical description of high incident energy (e,3e) processes, for which the first Born approximation should be suitable. In the case of helium, absolute experimental data for fivefold differential cross sections are available in coplanar geometry. We will review and discuss the divergencies existing between the results obtained with different theoretical models, and those appearing when compared to the experiments in particular with respect to the absolute scale. We will then discuss some results obtained in a recently proposed out of plane geometry.

  19. Self-management of oral anticoagulant therapy in two centers

    DEFF Research Database (Denmark)

    Nilsson, Hanna; Grove, E; Larsen, Torben Bjerregaard

    Self-management of oral anticoagulant therapy in two centers: 11.000 patient-years of follow-up H Nilsson1,2,3, EL Grove2, TB Larsen3, M Maegaard1, TD Christensen1 1Department of Cardiothoracic and Vascular Surgery & Institute of Clinical Medicine, Aarhus University Hospital, Aarhus; 2Department...... of Cardiology, Aarhus University Hospital, Aarhus; 3Department of Cardiology, Aalborg Hospital & Department of Health Science and Technology, Aalborg University, Aalborg, Denmark haana_86@hotmail.com Objectives: Patient-self-management (PSM) of oral anticoagulant therapy with vitamin K antagonists have...... clinical practice. Materials and methods: A case-series study including all patients who had passed an exam in PSM in the period 1995-2012 at Aarhus University Hospital or Aalborg University Hospital, including 2200 patients and 11000 patient-years in total. The effectiveness was measured using...

  20. Some remarks on the two-electron atom

    CERN Document Server

    Apostol, M

    1996-01-01

    New, approximate, two-electron wavefunctions are introduced for the two-electron atoms (cations), which account remarkably well for the ground-state energies and the lowest-excxited states (where available). A new scheme of electronic configurations is also proposed for the multi-electron atoms.

  1. A Tale of Two Electrons: Correlation at High Density

    CERN Document Server

    Loos, Pierre-François

    2010-01-01

    We review our recent progress in the determination of the high-density correlation energy $\\Ec$ in two-electron systems. Several two-electron systems are considered, such as the well known helium-like ions (helium), and the Hooke's law atom (hookium). We also present results regarding two electrons on the surface of a sphere (spherium), and two electrons trapped in a spherical box (ballium). We also show that, in the large-dimension limit, the high-density correlation energy of two opposite-spin electrons interacting {\\em via} a Coulomb potential is given by $\\Ec \\sim -1/(8D^2)$ for any radial external potential $V(r)$, where $D$ is the dimensionality of the space. This result explains the similarity of $\\Ec$ in the previous two-electron systems for $D=3$.

  2. Natural occupation numbers in two-electron quantum rings

    Energy Technology Data Exchange (ETDEWEB)

    Tognetti, Vincent, E-mail: vincent.tognetti@univ-rouen.fr [Normandy Univ., COBRA UMR 6014 & FR 3038, Université de Rouen, INSA Rouen, CNRS, 1 rue Tesniére, 76821 Mont Saint Aignan, Cedex (France); Loos, Pierre-François [Research School of Chemistry, Australian National University, Canberra ACT 2601 (Australia)

    2016-02-07

    Natural orbitals (NOs) are central constituents for evaluating correlation energies through efficient approximations. Here, we report the closed-form expression of the NOs of two-electron quantum rings, which are prototypical finite-extension systems and new starting points for the development of exchange-correlation functionals in density functional theory. We also show that the natural occupation numbers for these two-electron paradigms are in general non-vanishing and follow the same power law decay as atomic and molecular two-electron systems.

  3. Natural occupation numbers in two-electron quantum rings

    Science.gov (United States)

    Tognetti, Vincent; Loos, Pierre-François

    2016-02-01

    Natural orbitals (NOs) are central constituents for evaluating correlation energies through efficient approximations. Here, we report the closed-form expression of the NOs of two-electron quantum rings, which are prototypical finite-extension systems and new starting points for the development of exchange-correlation functionals in density functional theory. We also show that the natural occupation numbers for these two-electron paradigms are in general non-vanishing and follow the same power law decay as atomic and molecular two-electron systems.

  4. Natural occupation numbers in two-electron quantum rings.

    Science.gov (United States)

    Tognetti, Vincent; Loos, Pierre-François

    2016-02-07

    Natural orbitals (NOs) are central constituents for evaluating correlation energies through efficient approximations. Here, we report the closed-form expression of the NOs of two-electron quantum rings, which are prototypical finite-extension systems and new starting points for the development of exchange-correlation functionals in density functional theory. We also show that the natural occupation numbers for these two-electron paradigms are in general non-vanishing and follow the same power law decay as atomic and molecular two-electron systems.

  5. On the Beebe-Linderberg two-electron integral approximation

    Science.gov (United States)

    Røeggen, I.; Wisløff-Nilssen, E.

    1986-12-01

    The Beebe-Linderberg two-electron integral approximation, which is generated by a Cholesky decomposition of the two-electron integral matrix ([μν|λσ]), is slightly modified. On the basis of test calculations, two key questions concerning this approximation are discussed: The numerical rank of the two-electron integral matrix and the relationship between the integral threshold and electronic properties. The numerical results presented in this work suggest that the modified Beebe-Linderberg approximation might be considered as an alternative to effective core potential methods.

  6. Majorana solutions to the two-electron problem

    CERN Document Server

    Esposito, S

    2012-01-01

    A review of the known different methods and results devised to study the two-electron atom problem, appeared in the early years of quantum mechanics, is given, with particular reference to the calculations of the ground state energy of helium. This is supplemented by several, unpublished results obtained around the same years by Ettore Majorana, which results did not convey in his published papers on the argument, and thus remained unknown until now. Particularly interesting, even for current research in atomic and nuclear physics, is a general variant of the variational method, developed by Majorana in order to take directly into account, already in the trial wavefunction, the action of the full Hamiltonian operator of a given quantum system. Moreover, notable calculations specialized to the study of the two-electron problem show the introduction of the remarkable concept of an effective nuclear charge different for the two electrons (thus generalizing previous known results), and an application of the pertu...

  7. Two-electron quantum ring in short pulses

    Institute of Scientific and Technical Information of China (English)

    Poonam Silotia; Rakesh Kumar Meena; Vinod Prasad

    2015-01-01

    The response of two-electron quantum ring system to the short laser pulses of different shapes in the presence of external static electric field is studied. The variation of transition probabilities of the two-electron quatum ring from ground state to excited states with a number of parameters is shown and explained. The energy levels and wavefunctions of the system in the presence of static electric field are found by solving the time-independent Schr ¨odinger equation numerically by finite difference method. The shape of the pulse plays a dominant role on the dynamics.

  8. Attosecond-correlated dynamics of two electrons in argon

    Indian Academy of Sciences (India)

    V Sharma; N Camus; B Fischer; M Kremer; A Rudenko; B Bergues; M Kuebel; N G Johnson; M F Kling; T Pfeifer; J Ullrich; R Moshammer

    2014-01-01

    In this work we explored strong field-induced decay of doubly excited transient Coulomb complex Ar** → Ar2++2. We measured the correlated two-electron emission as a function of carrier envelop phase (CEP) of 6 fs pulses in the non-sequential double ionization (NSDI) of argon. Classical model calculations suggest that the intermediate doubly excited Coulomb complex loses memory of its formation dynamics. We estimated the ionization time difference between the two electrons from NSDI of argon and it is 200 ± 100 as (N Camus et al, Phys. Rev. Lett. 108, 073003 (2012)).

  9. Excitations and benchmark ensemble density functional theory for two electrons

    CERN Document Server

    Pribram-Jones, Aurora; Trail, John R; Burke, Kieron; Needs, Richard J; Ullrich, Carsten A

    2014-01-01

    A new method for extracting ensemble Kohn-Sham potentials from accurate excited state densities is applied to a variety of two electron systems, exploring the behavior of exact ensemble density functional theory. The issue of separating the Hartree energy and the choice of degenerate eigenstates is explored. A new approximation, spin eigenstate Hartree-exchange (SEHX), is derived. Exact conditions that are proven include the signs of the correlation energy components, the virial theorem for both exchange and correlation, and the asymptotic behavior of the potential for small weights of the excited states. Many energy components are given as a function of the weights for two electrons in a one-dimensional flat box, in a box with a large barrier to create charge transfer excitations, in a three-dimensional harmonic well (Hooke's atom), and for the He atom singlet-triplet ensemble, singlet-triplet-singlet ensemble, and triplet bi-ensemble.

  10. Excitations and benchmark ensemble density functional theory for two electrons

    Energy Technology Data Exchange (ETDEWEB)

    Pribram-Jones, Aurora; Burke, Kieron [Department of Chemistry, University of California-Irvine, Irvine, California 92697 (United States); Yang, Zeng-hui; Ullrich, Carsten A. [Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211 (United States); Trail, John R.; Needs, Richard J. [Theory of Condensed Matter Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom)

    2014-05-14

    A new method for extracting ensemble Kohn-Sham potentials from accurate excited state densities is applied to a variety of two-electron systems, exploring the behavior of exact ensemble density functional theory. The issue of separating the Hartree energy and the choice of degenerate eigenstates is explored. A new approximation, spin eigenstate Hartree-exchange, is derived. Exact conditions that are proven include the signs of the correlation energy components and the asymptotic behavior of the potential for small weights of the excited states. Many energy components are given as a function of the weights for two electrons in a one-dimensional flat box, in a box with a large barrier to create charge transfer excitations, in a three-dimensional harmonic well (Hooke's atom), and for the He atom singlet-triplet ensemble, singlet-triplet-singlet ensemble, and triplet bi-ensemble.

  11. CMS: Simulated Higgs to two jets and two electrons

    CERN Multimedia

    1997-01-01

    This track is an example of simulated data modelled for the CMS detector on the Large Hadron Collider (LHC) at CERN, which will begin taking data in 2008. Here a Higgs boson is produced which decays into two jets of hadrons and two electrons. The lines represent the possible paths of particles produced by the proton-proton collision in the detector while the energy these particles deposit is shown in blue.

  12. Quantum Transport in Solids: Two-Electron Processes.

    Science.gov (United States)

    1995-06-01

    The central objective of this research program has been to study theoretically the underlying principles of quantum transport in solids. The area of...research investigated has emphasized the understanding of two electron processes in quantum transport . The problems have been treated analytically to...the extent possible through the use of dynamical localized Wannier functions. These results have been and are being incorporated in a full quantum

  13. Dissipative two-electron transfer: A numerical renormalization group study

    Science.gov (United States)

    Tornow, Sabine; Bulla, Ralf; Anders, Frithjof B.; Nitzan, Abraham

    2008-07-01

    We investigate nonequilibrium two-electron transfer in a model redox system represented by a two-site extended Hubbard model and embedded in a dissipative environment. The influence of the electron-electron interactions and the coupling to a dissipative bosonic bath on the electron transfer is studied in different temperature regimes. At high temperatures, Marcus transfer rates are evaluated, and at low temperatures, we calculate equilibrium and nonequilibrium population probabilities of the donor and acceptor with the nonperturbative numerical renormalization group approach. We obtain the nonequilibrium dynamics of the system prepared in an initial state of two electrons at the donor site and identify conditions under which the electron transfer involves one concerted two-electron step or two sequential single-electron steps. The rates of the sequential transfer depend nonmonotonically on the difference between the intersite and on-site Coulomb interaction, which become renormalized in the presence of the bosonic bath. If this difference is much larger than the hopping matrix element, the temperature as well as the reorganization energy, simultaneous transfer of both electrons between donor and acceptor can be observed.

  14. Dynamics of two-electron excitations in helium

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, C.D.; Menzel, A.; Frigo, S.P. [Univ. of Central Florida, Orlando, FL (United States)] [and others

    1997-04-01

    Excitation of both electrons in helium offers a unique window for studying electron correlation at the most basic level in an atom in which these two electrons and the nucleus form a three-body system. The authors utilized the first light available at the U-8 undulator-SGM monochromator beamline to investigate the dynamic parameters, partial cross sections, differential cross sections, and photoelectron angular distribution parameters ({beta}), with a high resolving power for the photon beam and at the highly differential level afforded by the use of their electron spectrometer. In parallel, they carried out detailed calculations of the relevant properties by a theoretical approach that is based on the hyperspherical close-coupling method. Partial photoionization cross sections {sigma}{sub n}, and photoelectron angular distributions {beta}{sub n} were measured for all possible final ionic states He{sup +}(n) in the region of the double excitations N(K,T){sup A} up to the N=5 threshold. At a photon energy bandpass of 12 meV below the thresholds N=3, 4, and 5, this level of differentiation offers the most critical assessment of the dynamics of the two-electron excitations to date. The experimental data were seen to be very well described by the most advanced theoretical calculations.

  15. On the Classification of Two Center Orbits for Magical Black Holes

    CERN Document Server

    Andrianopoli, Laura; Ferrara, Sergio

    2013-01-01

    We report on recent work [4] concerning the determination of the two-centered generic charge orbits of magical $\\mathcal{N} = 2$ and maximal $\\mathcal{N} = 8$ supergravity theories in four dimensions.

  16. Magnetic alteration of entanglement in two-electron quantum dots

    CERN Document Server

    Simonovic, N S

    2015-01-01

    Quantum entanglement is analyzed thoroughly in the case of the ground and lowest states of two-electron axially symmetric quantum dots under a perpendicular magnetic field. The individual-particle and the center-of-mass representations are used to study the entanglement variation at the transition from interacting to noninteracting particle regimes. The mechanism of symmetry breaking due to the interaction, that results in the states with symmetries related to the later representation only, being entangled even at the vanishing interaction, is discussed. The analytical expression for the entanglement measure based on the linear entropy is derived in the limit of noninteracting electrons. It reproduces remarkably well the numerical results for the lowest states with the magnetic quantum number M>2 in the interacting regime. It is found that the entanglement of the ground state is a discontinuous function of the field strength. A method to estimate the entanglement of the ground state, characterized by the quan...

  17. Frustrated double ionization in two-electron triatomic molecules

    Science.gov (United States)

    Chen, A.; Price, H.; Staudte, A.; Emmanouilidou, A.

    2016-10-01

    Using a semiclassical model, we investigate frustrated double ionization (FDI) in D3+ , a two-electron triatomic molecule, when driven by an intense, linearly polarized, near-infrared (800 nm) laser field. We compute the kinetic energy release of the nuclei and find a good agreement between experiment and our model. We explore the two pathways of FDI and show that, with increasing field strength, over-the-barrier ionization overtakes tunnel ionization as the underlying mechanism of FDI. Moreover, we compute the angular distribution of the ion fragments for FDI and identify a feature that can potentially be observed experimentally and is a signature of only one of the two pathways of FDI.

  18. Frustrated double ionization in two-electron triatomic molecules

    CERN Document Server

    Chen, A; Staudte, A; Emmanouilidou, A

    2016-01-01

    Using a semi-classical model, we investigate frustrated double ionization (FDI) in $\\mathrm{D_3^+}$, a two-electron triatomic molecule, when driven by an intense, linearly polarized, near-infrared (800 nm) laser field. We do so using a semi-classical model. We find a good agreement between experiment and our model. We explore the two pathways of FDI and show that, with increasing field strength, over-the-barrier ionization overtakes tunnel ionization as the underlying mechanism of FDI. Moreover, we compute the angular distribution of the ion fragments for FDI and identify a feature that can be observed experimentally and that is a signature of only one of the two pathways of FDI.

  19. Complex dynamics in planar two-electron quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Schroeter, Sebastian Josef Arthur

    2013-06-25

    Quantum dots play an important role in a wide range of recent experimental and technological developments. In particular they are promising candidates for realisations of quantum bits and further applications in quantum information theory. The harmonically confined Hooke's atom model is experimentally verified and separates in centre-of-mass and relative coordinates. Findings that are contradictory to this separability call for an extension of the model, in particular changing the confinement potential. In order to study effects of an anharmonic confinement potential on spectral properties of planar two-electron quantum dots a sophisticated numerical approach is developed. Comparison between the Helium atom, Hooke's atom and an anharmonic potential model are undertaken in order to improve the description of quantum dots. Classical and quantum features of complexity and chaos are investigated and used to characterise the dynamics of the system to be mixed regular-chaotic. Influence of decoherence can be described by quantum fidelity, which measures the effect of a perturbation on the time evolution. The quantum fidelity of eigenstates of the system depends strongly on the properties of the perturbation. Several methods for solving the time-dependent Schrödinger equation are implemented and a high level of accuracy for long time evolutions is achieved. The concept of offset entanglement, the entanglement of harmonic models in the noninteracting limit, is introduced. This concept explains different questions raised in the literature for harmonic quantum dot models, recently. It shows that only in the groundstate the electrons are not entangled in the fermionic sense. The applicability, validity, and origin of Hund's first rule in general quantum dot models is further addressed. In fact Hund's first rule is only applicable, and in this case also valid, for one pair of singlet and triplet states in Hooke's atom. For more realistic models of two-electron

  20. Controlling autoionization in strontium two-electron-excited states

    Science.gov (United States)

    Fields, Robert; Zhang, Xinyue; Dunning, F. Barry; Yoshida, Shuhei; Burgdörfer, Joachim

    2016-05-01

    One challenge in engineering long-lived two-electron-excited states, i.e., so-called planetary atoms, is autoionization. Autoionization, however, can be suppressed if the outermost electron is placed in a high- n, n ~ 300 - 600 , high- L state because such states have only a very small overlap with the inner electron, even when this is also excited to a state of relatively high n and hence of relatively long lifetime. Here the L-dependence of the autoionization rate for high- n strontium Rydberg atoms is examined during excitation of the core ion 5 s 2S1 / 2 - 5 p 2P3 / 2 transition. Measurements in which the angular momentum of the Rydberg electron is controlled using a pulsed electric field show that the autoionization rate decreases rapidly with increasing L and becomes very small for values larger than ~ 20 . The data are analyzed with the aid of calculations undertaken using complex scaling. Research supported by the NSF and Robert A. Welch Foundation.

  1. Linear algebra of integrals in the quantum-mechanical two-center problem

    Energy Technology Data Exchange (ETDEWEB)

    Truskova, N.F.

    1978-09-01

    By means of commutation relations a number of formulas and recurrence relations are derived which interconnect the integrals necessary for calculating matrix elements in the quantum-mechanical two-center problem. This allows us to reduce the calculation of all possible integrals of this kind to that of only a finite number of them. Relations of the type of general orthogonality relations are derived for the two-center functions; these relations are satisfied separately in each of the ranges of variation of the coordinates xi and eta.

  2. Calculation of Two-center Nuclear Attraction Integrals over Slater Type Orbitals in Molecular Coordinate System

    Institute of Scientific and Technical Information of China (English)

    MAMEDOV,B.A.

    2004-01-01

    A closed analytical relation is derived for the two-center nuclear attraction integrals over Slater type orbitals (STOs) in terms of binomial coefficients. This formula can be used in highly accurate calculations of the nuclear attraction integrals. The relationships obtained are valid for arbitrary values of quantum numbers and screening constants of STOs and location of nuclei.

  3. Two-center clinical trial of implant-retained mandibular overdentures versus complete dentures - Chewing ability

    NARCIS (Netherlands)

    Geertman, ME; Boerrigter, EM; VantHof, MA; VanWaas, MAJ; vanOort, RP; Boering, G; Kalk, W

    This study is a two-center clinical trial with the aim to assess the treatment effects of implant-retained mandibular overdentures versus conventional complete dentures. Treatment had been assigned according to a balanced allocation method. The following criteria were used to enhance the

  4. Calculation of two-center one-electron molecular integrals with STOs. [BICEN

    Energy Technology Data Exchange (ETDEWEB)

    Rico, J.F.; Lopez, R.; Paniagua, M.; Ramirez, G. (Universidad Autonoma de Madrid (Spain). Dept. de Quimica Fisica y Quimica Cuantica)

    1991-05-01

    A program for the calculation of two-center one-electron integrals (overlap, nuclear attraction and kinetic energy) between real Slater-type orbitals (STOs) is reported. The integrals are obtained by recursion over simple auxiliary matrices, whose elements are calculated in terms of further auxiliary functions evaluated in a quick and accurate way. (orig.).

  5. Non-Collision Singularities in the Planar Two-Center-Two-Body Problem

    Science.gov (United States)

    Xue, Jinxin; Dolgopyat, Dmitry

    2016-08-01

    In this paper, we study a restricted four-body problem called the planar two-center-two-body problem. In the plane, we have two fixed centers Q 1 and Q 2 of masses 1, and two moving bodies Q 3 and Q 4 of masses {μ≪ 1}. They interact via Newtonian potential. Q 3 is captured by Q 2, and Q 4 travels back and forth between two centers. Based on a model of Gerver, we prove that there is a Cantor set of initial conditions that lead to solutions of the Hamiltonian system whose velocities are accelerated to infinity within finite time avoiding all earlier collisions. This problem is a simplified model for the planar four-body problem case of the Painlevé conjecture.

  6. Two-Center Gaussian Potential Well for Studying Light Nucleus in Cluster Structure

    Directory of Open Access Journals (Sweden)

    Nafiseh Roshanbakht

    2017-01-01

    Full Text Available The clustering phenomena are very important to determine structure of light nuclei and deformation of spherical shape is inevitable. Hence, we calculated the energy levels of two-center Gaussian potential well including spin-orbit coupling by solving the Schrödinger equation in the cylindrical coordinates. This model can predict the spin and parity of the light nuclei that have two identical cluster structures.

  7. Two center shell model with Woods-Saxon potentials: adiabatic and diabatic states in fusion

    CERN Document Server

    Díaz-Torres, A; Diaz-Torres, Alexis; Scheid, Werner

    2005-01-01

    A realistic two-center shell model for fusion is proposed, which is based on two spherical Woods-Saxon potentials and the potential separable expansion method. This model describes the single-particle motion in a fusing system. A technique for calculating stationary diabatic states is suggested which makes use of the formal definition of those states, i.e., they minimize the radial nonadiabatic coupling between the adiabatic states. As an example the system $^{16}$O + $^{40}$Ca $\\to$ $^{56}$Ni is discussed.

  8. Integrability and separation of variables in Calogero-Coulomb-Stark and two-center Calogero-Coulomb systems

    CERN Document Server

    Hakobyan, Tigran

    2015-01-01

    We define the integrable N-dimensional Calogero-Coulomb-Stark and two-center Calogero-Coulomb systems and construct their constants of motion via the Dunkl operators. Their Schroedinger equations decouple in parabolic and elliptic coordinates, respectively, into the set of three differential equations like for the Coulomb-Stark and two-center Coulomb problems.

  9. Calculation of the relativistic Bethe logarithm in the two-center problem

    CERN Document Server

    Korobov, Vladimir I; Karr, Jean-Philippe

    2013-01-01

    We present a variational approach to evaluate relativistic corrections of order \\alpha^2 to the Bethe logarithm for the ground electronic state of the Coulomb two center problem. That allows to estimate the radiative contribution at m\\alpha^7 order in molecular-like three-body systems such as hydrogen molecular ions H_2^+ and HD^+, or antiprotonic helium atoms. While we get 10 significant digits for the nonrelativistic Bethe logarithm, calculation of the relativistic corrections is much more involved especially for small values of bond length R. We were able to achieve a level of 3-4 significant digits starting from R=0.2 bohr, that will allow to reach 10^{-10} relative uncertainty on transition frequencies.

  10. Calculation of the relativistic Bethe logarithm in the two-center problem

    Science.gov (United States)

    Korobov, Vladimir I.; Hilico, L.; Karr, J.-Ph.

    2013-06-01

    We present a variational approach to evaluate relativistic corrections of order α2 to the Bethe logarithm for the ground electronic state of the Coulomb two-center problem. That allows us to estimate the radiative contribution at mα7 order in molecular-like three-body systems such as hydrogen molecular ions H2+ and HD+ or antiprotonic helium atoms. While we get ten significant digits for the nonrelativistic Bethe logarithm, calculation of the relativistic corrections is much more involved, especially for small values of bond length R. We were able to achieve a level of three to four significant digits starting from R=0.2 bohr, which will allow us to reach 10-10 relative uncertainty on transition frequencies.

  11. Real-time electron dynamics simulation of two-electron transfer reactions induced by nuclear motion

    Science.gov (United States)

    Suzuki, Yasumitsu; Yamashita, Koichi

    2012-04-01

    Real-time electron dynamics of two-electron transfer reactions induced by nuclear motion is calculated by three methods: the numerically exact propagation method, the time-dependent Hartree (TDH) method and the Ehrenfest method. We find that, as long as the nuclei move as localized wave packets, the TDH and Ehrenfest methods can reproduce the exact electron dynamics of a simple charge transfer reaction model containing two electrons qualitatively well, even when nonadiabatic transitions between adiabatic states occur. In particular, both methods can reproduce the cases where a complete two-electron transfer reaction occurs and those where it does not occur.

  12. Two-electron reduction of ethylene carbonate: a quantum chemistry re-examination of mechanisms

    CERN Document Server

    Leung, Kevin

    2013-01-01

    Passivating solid-electrolyte interphase (SEI) films arising from electrolyte decomposition on low-voltage lithium ion battery anode surfaces are critical for battery operations. We review the recent theoretical literature on electrolyte decomposition and emphasize the modeling work on two-electron reduction of ethylene carbonate (EC, a key battery organic solvent). One of the two-electron pathways, which releases CO gas, is re-examined using simple quantum chemistry calculations. Excess electrons are shown to preferentially attack EC in the order (broken EC^-) > (intact EC^-) > EC. This confirms the viability of two electron processes and emphasizes that they need to be considered when interpreting SEI experiments. An estimate of the crossover between one- and two-electron regimes under a homogeneous reaction zone approximation is proposed.

  13. Vacuum polarization screening corrections to the ground state energy of two-electron ions

    CERN Document Server

    Artemiev, A N; Yerokhin, V A

    1997-01-01

    Vacuum polarization screening corrections to the ground state energy of two-electron ions are calculated in the range $Z=20-100$. The calculations are carried out for a finite nucleus charge distribution.

  14. Quantitative and qualitative assessment of structural magnetic resonance imaging data in a two-center study

    Directory of Open Access Journals (Sweden)

    Chalavi Sima

    2012-08-01

    Full Text Available Abstract Background Multi-center magnetic resonance imaging (MRI studies present an opportunity to advance research by pooling data. However, brain measurements derived from MR-images are susceptible to differences in MR-sequence parameters. It is therefore necessary to determine whether there is an interaction between the sequence parameters and the effect of interest, and to minimise any such interaction by careful choice of acquisition parameters. As an exemplar of the issues involved in multi-center studies, we present data from a study in which we aimed to optimize a set of volumetric MRI-protocols to define a protocol giving data that are consistent and reproducible across two centers and over time. Methods Optimization was achieved based on data quality and quantitative measures, in our case using FreeSurfer and Voxel Based Morphometry approaches. Our approach consisted of a series of five comparisons. Firstly, a single-center dataset was collected, using a range of candidate pulse-sequences and parameters chosen on the basis of previous literature. Based on initial results, a number of minor changes were implemented to optimize the pulse-sequences, and a second single-center dataset was collected. FreeSurfer data quality measures were compared between datasets in order to determine the best performing sequence(s, which were taken forward to the next stage of testing. We subsequently acquired short-term and long-term two-center reproducibility data, and quantitative measures were again assessed to determine the protocol with the highest reproducibility across centers. Effects of a scanner software and hardware upgrade on the reproducibility of the protocols at one of the centers were also evaluated. Results Assessing the quality measures from the first two datasets allowed us to define artefact-free protocols, all with high image quality as assessed by FreeSurfer. Comparing the quantitative test and retest measures, we found high within

  15. The clinical manifestations and survival of systemic lupus erythematosus patients in Turkey: report from two centers.

    Science.gov (United States)

    Pamuk, O N; Akbay, F G; Dönmez, S; Yilmaz, N; Calayir, G B; Yavuz, S

    2013-11-01

    Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with a variety of clinical features. Survival has become longer as a result of better treatment modalities and better supportive care. There is no information on survival of SLE patients in Turkey. We evaluated clinical features and survival in SLE patients in two rheumatology departments. All SLE patients being followed up by the Department of Rheumatology, Trakya University Medical Faculty, and the Department of Rheumatology, Marmara University Medical Faculty, over the 1996-2012 period were included. Patients were diagnosed with SLE if they fulfilled at least four American College of Rheumatology (ACR) criteria. The clinical and laboratory features, mortality data were obtained from medical charts. We had 428 SLE patients, and women (399 patients, 93.2%) far outnumbered men (29 patients, 6.8%). The mean age at the time of SLE diagnosis was 40.3 ± 12.4 years. The most frequent clinical manifestations were arthritis (76.9%) and photosensitivity (70.1%). Renal disease was present in 32.9% of patients and neurological involvement in 12.9% of patients. After a median follow-up of 60 months, 19 patients died. The most frequent causes of death were ischemic heart disease, chronic renal failure and sepsis. The rate of five-year survival was 96%; 10-year survival, 92%; and 15-year survival, 88.8%. Multivariate Cox analysis showed that serositis at the time of diagnosis, SLE disease activity index (SLEDAI) score 6, and autoimmune hemolytic anemia were independent prognostic factors. Data from two centers in Northwestern Turkey show that the mortality rate for SLE is similar to the rate in Western countries.

  16. Allograft arthrodesis treatment of bone tumors: a two-center study.

    Science.gov (United States)

    Donati, D; Giacomini, S; Gozzi, E; Salphale, Y; Mercuri, M; Mankin, Henry J; Springfield, Dempsy S; Gebhardt, Mark C

    2002-07-01

    The current study consists of an outcome review of a consecutive series of 92 patients with knee arthrodesis using an allograft, done for malignant or aggressive tumors in two centers on different continents during a period of 18 years (mean followup, 5 +/- 4 years). The data were compiled by creating a computerized file using the information provided by both centers. Seventy-five of the patients (81%) had high-grade nonmetastatic tumors (Stage II), mostly osteosarcoma. In addition seven (8%) had metastases at outset (Stage III) and the remaining 10 (11%) had benign disease, mostly giant cell tumor or revision procedures for failed allograft or total joint replacement. Seventy-two patients (78%) had distal femoral lesions (78%) whereas the proximal tibia was the site of the tumor in 20 patients (22%). The average age of the patients was 23 +/- 16 years; 51 were males and 41 were females. Tumor complications were a major problem for patients in the series. Thirty-four percent of the patients died, 47% had metastases develop, and 9% had a local recurrence. Allograft complications included an infection rate of 20%, a fracture rate of 25%, and a nonunion rate of 44%. Repeat surgery was required for more than 50% of the patients with 26 requiring one additional operation, 11 requiring two, and 10 requiring three or more operations. Nineteen of the patients required an amputation (20%), only four of which were for recurrent tumor. When these data were compared with data for a control series of 880 patients with allografts other than allograft arthrodeses, the complications were greater and the outcome less successful, suggesting that other approaches should be considered unless there are special indications for this procedure.

  17. ATLAS proton-proton event containing two electrons and two muons

    CERN Multimedia

    ATLAS Collaboration

    2011-01-01

    An event with two identified muons and two identified electrons from a proton- proton collision in ATLAS. This event is consistent with coming from two Z particles decaying: one Z decays to two muons, the other to two electrons. Such events are produced by Standard Model processes without Higgs particles. They are also a possible signature for Higgs particle production, but many events must be analysed together in order to tell if there is a Higgs signal. The two muons are picked out as red tracks penetrating right through the detector. The two electrons are picked out as green tracks in the central, inner detector, matching narrow green clusters of energy in the barrel part of the calorimeters. The inset at the bottom right shows a map of the energy seen in the detector: the two big yellow spikes correspond to the two electrons.

  18. Study of two-electron jumps in relaxation of Coulomb glasses

    Energy Technology Data Exchange (ETDEWEB)

    Bergli, J. [Department of Physics, University of Oslo, Blindern (Norway); Somoza, A.M.; Ortuno, M. [Departamento de Fisica - CIOyN, Universidad de Murcia (Spain)

    2009-12-15

    A long-standing debate in the theory of hopping insulators concerns the role of multi-electron transitions in the dynamics of the system. The natural assumption is that as temperature is lowered, two-electron transitions will play an increasingly important role since they provide a way of tunneling through additional energy barriers which would be energetically unfavorable as successive one-electron transitions. This was disputed in[1], but later it was seen in[2]. The reason for this discrepancy is not clear and deserves further attention. One point where the two approaches diverged was in the selection and weighting of the two-electron transitions relative to one-electron transitions. We present calculations of the transition rates to second order in the tunneling matrix element, which will be used in improved numerical studies. We compare results for only one-electron jumps with results including also two-electron jumps. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  19. Role of Interactions in Electronic Structure of a Two-Electron Quantum Dot Molecule

    Institute of Scientific and Technical Information of China (English)

    DONG Qing-Rui; XU Ying-Qiang; ZHANG Shi-Yong; NIU Zhi-Chuan

    2004-01-01

    @@ We have studied a two-electron quantum dot molecule in a magnetic field. The electron interaction is treated accurately by the direct diagonalization of the Hamiltonian matrix. We calculate two lowest energy levels of the two-electron quantum dot molecule in a magnetic field. Our results show that the electron interactions are significant, as they can change the total spin of the two-electron ground state of the system by adjusting the magnetic field between S = 0 and S = 1. The energy difference △E between the lowest S = 0 and S = 1 states is shown as a function of the axial magnetic field. We found that the energy difference between the lowest S = 0 and S = 1 states in the strong-B S = 0 state varies linearly. Our results provide a possible realization for a qubit to be fabricated by current growth techniques.

  20. Quantum ballistic transport by interacting two-electron states in quasi-one-dimensional channels

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Danhong [Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico 87117 (United States); Center for High Technology Materials, University of New Mexico, 1313 Goddard St SE, Albuquerque, New Mexico 87106 (United States); Gumbs, Godfrey [Center for High Technology Materials, University of New Mexico, 1313 Goddard St SE, Albuquerque, New Mexico 87106 (United States); Abranyos, Yonatan [Department of Physics and Astronomy, Hunter College of the City University of New York, 695 Park Avenue, New York, New York 10065 (United States); Pepper, Michael; Kumar, Sanjeev [Department of Electronic and Electrical Engineering, University College London, London, WC1E 7JE (United Kingdom); London Centre for Nanotechnology, 17-19 Gordon Street, London, WC1H 0AH (United Kingdom)

    2015-11-15

    For quantum ballistic transport of electrons through a short conduction channel, the role of Coulomb interaction may significantly modify the energy levels of two-electron states at low temperatures as the channel becomes wide. In this regime, the Coulomb effect on the two-electron states is calculated and found to lead to four split energy levels, including two anticrossing-level and two crossing-level states. Moreover, due to the interplay of anticrossing and crossing effects, our calculations reveal that the ground two-electron state will switch from one anticrossing state (strong confinement) to a crossing state (intermediate confinement) as the channel width gradually increases and then back to the original anticrossing state (weak confinement) as the channel width becomes larger than a threshold value. This switching behavior leaves a footprint in the ballistic conductance as well as in the diffusion thermoelectric power of electrons. Such a switching is related to the triple spin degeneracy as well as to the Coulomb repulsion in the central region of the channel, which separates two electrons away and pushes them to different channel edges. The conductance reoccurrence region expands from the weak to the intermediate confinement regime with increasing electron density.

  1. Relaxation and Dephasing in a Two-Electron 13C Nanotube Double Quantum Dot

    DEFF Research Database (Denmark)

    Churchill, H O H; Kuemmeth, Ferdinand; Harlow, J W;

    2009-01-01

    We use charge sensing of Pauli blockade (including spin and isospin) in a two-electron 13C nanotube double quantum dot to measure relaxation and dephasing times. The relaxation time T1 first decreases with a parallel magnetic field and then goes through a minimum in a field of 1.4 T. We attribute...

  2. Observation and spectroscopy of a two-electron Wigner molecule in an ultraclean carbon nanotube

    DEFF Research Database (Denmark)

    Pecker, S.; Kuemmeth, Ferdinand; Secchi, A.;

    2013-01-01

    Two electrons on a string form a simple model system where Coulomb interactions are expected to play an interesting role. In the presence of strong interactions, these electrons are predicted to form a Wigner molecule, separating to the ends of the string. This spatial structure is believed...

  3. Calculation of differential cross section for dielectronic recombination with two-electron uranium

    CERN Document Server

    Lyashchenko, Konstantin N

    2016-01-01

    Calculation of the differential cross section for the dielectronic recombination with two-electron uranium within the framework of QED is presented. The polarization of the emitted photon is investigated. The contributions of the Breit interaction and the interference of the photon multipoles are studied.

  4. Dimensionality effect on two-electron energy spectrum: A fractional-dimension-based formulation

    Energy Technology Data Exchange (ETDEWEB)

    Correa, R.; Gutiérrez, W.; Mikhailov, I. [Escuela de Física, Universidad Industrial de Santander, A.A. 678, Bucaramanga (Colombia); Fulla, M.R. [Escuela de Física, Universidad Nacional de Colombia, A.A. 3840, Medellín (Colombia); Marín, J.H., E-mail: jhmarin@unal.edu.co [Escuela de Física, Universidad Nacional de Colombia, A.A. 3840, Medellín (Colombia)

    2015-07-17

    We analyze the spectrum of two-electron quantum dot with anisotropic parabolic confinement by using the fractional-dimension formulation which allows us to reduce the two-particle problem to two equations for independent particles in an effective space with variable dimension, ranging between two and three for ellipsoidal-shaped quantum dots and between one and two for elliptical-shaped quantum disks. The dependencies of energy levels on the heterostructure sizes for quantum dots, disks and wires are presented. - Highlights: • We report the two-electron eigenenergies in a quantum dot with anisotropic parabolic confinement. • Our model is versatile enough to consider changes in the dimension space from 3 to 2 and 2 to 1. • The two-electron structure is calculated in integer and fractional dimensional spaces. • The two-electron energy structure is sensitive to the quantum dot size and morphology changes. • The electron–electron Coulomb interaction is strongly dependent on the space dimensionality.

  5. Highly accurate wavefunctions for two-electron systems using two parameteres

    CERN Document Server

    Chauhan, Rabeet Singh

    2015-01-01

    It is shown for two electron atoms that ground-state wavefunctions of the form $\\Psi(\\vec{r_{1}}, \\vec{r_{2}})=\\phi(\\vec{r_{1}})\\phi(\\vec{r_{2}})(\\cosh ar_{1}+\\cosh ar_{2})(1+0.5 r_{12}e^{-b r_{12}})$ where $\\vec{r_{1}}$ and $\\vec{r_{2}}$ are the coordinates of two electrons and $r_{12}=|\\vec{r_{1}}-\\vec{r_{2}}|$, can be made highly accurate by optimizing $a$, $b$ and $\\phi$. This is done by solving a variationally derived equation for $\\phi$ for a given $a$ and $b$ and finding $a$ and $b$ so that the expectation value of the Hamiltonian is minimum. For the set $\\{a, b, \\phi\\}$ the values for various quantities obtained from the above wavefunction are compared with those given by $204$-parameter wavefunction of Koga et al. and are found to be matching quite accurately(within ppm) with them.

  6. Electron Bifurcation: Thermodynamics and Kinetics of Two-Electron Brokering in Biological Redox Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    King, Paul W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lubner, Carolyn E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mulder, David W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhang, Peng [Duke University; Yuly, Jonathon [Duke University; Peters, John W. [Washington State University; Beratan, David N. [Duke University

    2017-09-06

    How can proteins drive two electrons from a redox active donor onto two acceptors at very different potentials and distances? And how can this transaction be conducted without dissipating very much energy or violating the laws of thermodynamics? Nature appears to have addressed these challenges by coupling thermodynamically uphill and downhill electron transfer reactions, using two-electron donor cofactors that have very different potentials for the removal of the first and second electron. Although electron bifurcation is carried out with near perfection from the standpoint of energy conservation and electron delivery yields, it is a biological energy transduction paradigm that has only come into focus recently. This Account provides an exegesis of the biophysical principles that underpin electron bifurcation.

  7. Coulomb barrier and exchange interaction in dynamical two-electron systems

    Science.gov (United States)

    Gregoire, Maxwell; Lougovski, Pavel; Batelaan, Herman

    2012-06-01

    Recent electron sources can produce pulses containing multiple electrons that are confined both laterally and longitudinally. Given that the highest reported degeneracy for continuous sources of free electrons is about 10-4, it would be interesting to know the degeneracy for these pulsed sources. We previously studied one-dimensional two-electron degeneracy [1], and we now study three-dimensional two-electron degeneracy as a function of time. Our primary goal is to use this project as a necessary step to studying three-dimensional n-electron degeneracy. Our second goal is to develop a theory that predicts the outcome of Hasselbach's experiment demonstrating the Hanbury Brown-Twiss Effect [2] for free electrons.[4pt] [1] Lougovski P, and Batelaan H, Phys. Rev. A 84, 023417 (2011).[0pt] [2] Kiesel H, Renz A, and Hasselbach F, Nature. 418, 392-4 (2002).

  8. A compact terahertz free-electron laser with two gratings driven by two electron-beams

    Science.gov (United States)

    Liu, Weihao; Lu, Yalin; Wang, Lin; Jia, Qika

    2017-02-01

    We proposed and investigated a novel terahertz free-electron laser, which is based on two gratings driven by two electron-beams. Two gratings are symmetrically arranged to form an open-cavity. Two electron-beams generate special Smith-Purcell radiations, respectively, from two gratings. When radiation interferes constructively, operation modes of the open-cavity are excited and then amplified by beam-wave interactions. By means of particle-in-cell simulations, we have shown that, with compact equipments and available electron-beams, this scheme can generate radiation with power and efficiency being higher than those of majority radiation sources in the vicinity region of 1 THz. It can promisingly be developed as a high-power, high-efficiency, and compact terahertz source for practice.

  9. Fourier transform technique in variational treatment of two-electron parabolic quantum dot

    Institute of Scientific and Technical Information of China (English)

    S.(S)akiro(g)lu; A.Yildiz; (U).Dogan; K.Akgüng(o)r; H.Epik; Y.Ergün; H.Sarl; I.S(o)kmen

    2009-01-01

    In this work,we propose an efficient method of reducing the computational effort of variational calculation with a Hylleraas-like trial wavefunction.The method consists of introducing integral transforms for the terms as r12k exp (-λr12)which provide the calculation of the expectation value of energy and the relevant matrix elements to be done analytically over single-electron coordinates instead of Hylleraas coordinates.We have used this method to calculate the ground state energy of a two-electron system in a spherical dot and a disk-like quantum dot separately.Under parabolic confinement potential and within effective mass approximation size and shape effects of quantum dots on the ground state energy of two electrons have been investigated.The calculation shows that our results even with a small number of basis states axe in good agreement with previous theoretical results.

  10. The structure of approximate two electron wavefunctions in intense laser driven ionization dynamics

    CERN Document Server

    Sato, Takeshi

    2014-01-01

    The structure of approximate two electron wavefunction is deeply investigated, both theoretically and numerically, in the strong-field driven ionization dynamics. Theoretical analyses clarify that for two electron singlet systems, the previously proposed time-dependent extended Hartree-Fock (TD-EHF) method [Phys. Rev. A 51, 3999 (1995)] is equivalent to the multiconfiguration time-dependent Hartree-Fock method with two occupied orbitals. The latter wavefunction is further transformed into the natural expansion form, enabling the direct propagation of the natural orbitals (NOs). These methods, as well as the conventional time-dependent Hartree-Fock (TDHF) method, are numerically assessed for the description of ionization dynamics of one-dimensional helium atom model. This numerical analysis (i) explains the reason behind the well-known failure of TDHF method to describe tunneling ionization, (ii) demonstrates the interpretive power of the TD-EHF wavefunction both in the original nonorthogonal and the NO-based ...

  11. Computation of energy states of hydrogenic quantum dot with two-electrons

    Science.gov (United States)

    Yakar, Y.; Özmen, A.; ćakır, B.

    2016-03-01

    In this study we have investigated the electronic structure of the hydrogenic quantum dot with two electrons inside an impenetrable potential surface. The energy eigenvalues and wavefunctions of the ground and excited states of spherical quantum dot have been calculated by using the Quantum Genetic Algorithm (QGA) and Hartree-Fock Roothaan (HFR) method, and the energies are investigated as a function of dot radius. The results show that as dot radius increases, the energy of quantum dot decreases.

  12. Quantum Size Effects on Two Electrons and Two Holes in Double-Layer Quantum Dots

    Institute of Scientific and Technical Information of China (English)

    XIE Wen-Fang; ZHU Wu

    2002-01-01

    We propose a procedure to solve exactly the Schrodinger equation for a system of two electrons and two holes in a double-layer quantum dot by using the method of few-body physics. The features of the low-lying spectra have been deduced based on symmetry. The binding energies of the ground state are obtained as a function of the electron-to-hole mass ratio σ for a few values of the quantum dot size.

  13. Two-Electron Energy Spectrum in a Parabolic Quantum Dot Under a Magnetic Field

    Institute of Scientific and Technical Information of China (English)

    XIE Wen-Fang

    2003-01-01

    Two interacting electrons in a harmonic oscillator potential under the influence of a perpendicular homo-geneous magnetic field are considered. The energies of two-electron quantum dots with the electron-LO-phonon couplingas a function of magnetic field are calculated. Calculations are made by using the method of few-body physics withinthe effective-mass approximation. Our results show that the electron-LO-phonon coupling effect is very important insemiconductor quantum dots.

  14. Frustrated double and single ionization in a two-electron triatomic molecule H$^+_3$

    CERN Document Server

    Chen, A; Price, H; Emmanouilidou, A

    2016-01-01

    Using a semi-classical model, we study the formation of highly excited neutral fragments during the fragmentation of $\\mathrm{H_3^+}$, a two-electron triatomic molecule, driven by an intense near-IR laser field. To do so, we first formulate a microcanonical distribution for arbitrary one-electron triatomic molecules. We then study frustrated double and single ionization in strongly-driven $\\mathrm{H_3^+}$ and compute the kinetic energy release of the nuclei for these two processes. Moreover, we investigate the dependence of frustrated ionization on the strength of the laser field as well as on the geometry of the initial molecular state.

  15. Analytic derivatives for the Cholesky representation of the two-electron integrals.

    Science.gov (United States)

    Aquilante, Francesco; Lindh, Roland; Pedersen, Thomas Bondo

    2008-07-21

    We propose a formalism for calculating analytic derivatives of the electronic energy with respect to nuclear coordinates using Cholesky decomposition of the two-electron integrals. The formalism is derived by exploiting the equivalence of Cholesky decomposition and density fitting when a suitable auxiliary basis set is used for expanding atomic orbital product densities in the latter. An implementation of gradients at the nonhybrid density functional theory level is presented, and sample calculations demonstrate that the errors in equilibrium geometries due to the Cholesky representation of the integrals can be controlled by adjusting the decomposition threshold.

  16. Effect of Coulomb Interaction on Dynamical Localization in a Two-Electron Quantum-Dot Molecule

    Institute of Scientific and Technical Information of China (English)

    WANG Li-Min; DUAN Su-Qing; ZHAO Xian-Geng; LIU Cheng-Shi

    2004-01-01

    The combined interaction of Coulomb interaction and ac fields with two electrons in a quantum dot molecule is studied respectively with numerical simulation, perturbation theory and the approximation of driven two-level model. The dynamical localization occurs with the ac field whose ratio of the amplitude to the angular frequency is a root of n-order Bessel functions, where n is determined by the Coulomb interaction energy. Such results are explained with either the driven two-level approximation or the degenerated three-level model and verified by the numerical simulations.

  17. t-SURFF: Fully Differential Two-Electron Photo-Emission Spectra

    CERN Document Server

    Scrinzi, Armin

    2012-01-01

    The time dependent surface flux (t-SURFF) method is extended to single and double ionization of two electron systems. Fully differential double emission spectra by strong pulses at extreme UV and infrared wave length are calculated using simulation volumes that only accommodate the effective range of the atomic binding potential and the quiver radius of free electrons in the external field. For a model system we find pronounced dependence of shake-up and non-sequential double ionization on phase and duration of the laser pulse. Extension to fully three-dimensional calculations is discussed.

  18. Theory of Square-Wave Voltammetry of Two-Electron Reduction with the Adsorption of Intermediate

    Directory of Open Access Journals (Sweden)

    Milivoj Lovric

    2012-01-01

    Full Text Available Thermodynamically unstable intermediate of fast and reversible two-electron electrode reaction can be stabilized by the adsorption to the electrode surface. In square-wave voltammetry of this reaction mechanism, the split response may appear if the electrode surface is not completely covered by the adsorbed intermediate. The dependence of the difference between the net peak potentials of the prepeak and postpeak on the square-wave frequency is analyzed theoretically. This relationship can be used for the estimation of adsorption constant.

  19. Dynamic Localization Condition of Two Electrons in a Strong dc-ac Biased Quantum Dot Molecule

    Institute of Scientific and Technical Information of China (English)

    WANG Li-Min; DUAN Su-Qing; ZHAO Xian-Geng; LIU Cheng-Shi

    2004-01-01

    @@ We present a perturbation investigation of dynamic localization condition of two electrons in a strong dc-ac biased quantum dot molecule. By reducing the system to an Hubbard-type effective two-site model and by applying Floquet theory, we find that the dynamical localization phenomenon occurs under certain values of the large strength of the dc and ac field. This demonstrates the possibility of using appropriate dc-ac fields to manipulate dynamical localized states in mesoscopic devices, which is an essential component of practical schemes for quantum information processing. Our conclusion is instructive to the field of quantum function devices.

  20. Two-electron Oxidation of a Twisted Non Anti-aromatic 40π Expanded Isophlorin

    Indian Academy of Sciences (India)

    PRACHI GUPTA; SANTOSH P PANCHAL; VENKATARAMANARAO G ANAND

    2016-11-01

    Expanded isophlorins are typical examples for stable anti-aromatic systems. Paratropic ring current effects are observed in their NMR spectra mainly due to their planar conformation. Herein we report the synthesis of the first twisted 40π expanded isophlorin and also its two-electron oxidation to a 38π dication. It sustains the twisted conformation for the 4nπ and (4n+2)π electrons. Due to the non-planar conformation, they do not display ring current effects in their respective 1H NMR spectrum. NICS calculations reveal the non-(anti)aromatic features for the neutral 40π and the 38π dication species.

  1. Relaxation and Dephasing in a Two-Electron 13C Nanotube Double Quantum Dot

    DEFF Research Database (Denmark)

    Churchill, H O H; Kuemmeth, Ferdinand; Harlow, J W

    2009-01-01

    We use charge sensing of Pauli blockade (including spin and isospin) in a two-electron 13C nanotube double quantum dot to measure relaxation and dephasing times. The relaxation time T1 first decreases with a parallel magnetic field and then goes through a minimum in a field of 1.4 T. We attribute...... both results to the spin-orbit-modified electronic spectrum of carbon nanotubes, which at high field enhances relaxation due to bending-mode phonons. The inhomogeneous dephasing time T2* is consistent with previous data on hyperfine coupling strength in 13C nanotubes....

  2. Comparative characterization of two-electron wavefunctions using information-theory measures

    Energy Technology Data Exchange (ETDEWEB)

    Howard, I.A., E-mail: ihoward@vub.ac.b [Department of Chemistry (ALGC), Free University of Brussels (VUB), B-1050, Brussels, Belgium/Member of the QCMM-Alliance Ghent-Brussels (Belgium); Borgoo, A.; Geerlings, P. [Department of Chemistry (ALGC), Free University of Brussels (VUB), B-1050, Brussels, Belgium/Member of the QCMM-Alliance Ghent-Brussels (Belgium); Sen, K.D. [School of Chemistry, University of Hyderabad, Hyderabad 500046 (India)

    2009-08-31

    Information-theory measures, in particular the Shannon entropy, Fisher information and statistical complexity, are used to discuss the variations among several commonly encountered model two-electron correlated wavefunctions. The Hookean, Moshinsky, and three-parameter Chandrasekhar wavefunctions are considered in real and momentum space, with further comparisons to the Hookean-Hartree-Fock (HF) wavefunction of Ragot, the numerical HF limit, and the hydrogenic (pure Coulomb) limit. The purpose of the study is to quantitatively analyze the effect of different models for inclusion of electron-electron correlation on information-theoretical measures, including statistical complexity, which characterize the electron distribution in position and momentum space.

  3. Double ionization in R -matrix theory using a two-electron outer region

    Science.gov (United States)

    Wragg, Jack; Parker, J. S.; van der Hart, H. W.

    2015-08-01

    We have developed a two-electron outer region for use within R -matrix theory to describe double ionization processes. The capability of this method is demonstrated for single-photon double ionization of He in the photon energy region between 80 and 180 eV. The cross sections are in agreement with established data. The extended R -matrix with time dependence method also provides information on higher-order processes, as demonstrated by the identification of signatures for sequential double ionization processes involving an intermediate He+ state with n =2 .

  4. Propagation and oblique collision of electron-acoustic solitons in two-electron-populated quantum plasmas

    Indian Academy of Sciences (India)

    M Akbari-Moghanjoughi; N Ahmadzadeh-Khosroshahi

    2011-08-01

    Oblique interaction of small- but finite-amplitude KdV-type electron-acoustic solitary excitations is examined in an unmagnetized two-electron-populated degenerate quantum electron–ion plasma in the framework of quantum hydrodynamics model using the extended Poincaré–Lighthill–Kuo (PLK) perturbation method. Critical plasma parameter is found to distinguish the types of solitons and their interaction phase-shifts. It is shown that, depending on the critical quantum diffraction parameter cr, both compressive and rarefactive solitary excitations may exist in this plasma and their collision phase-shifts can be either positive or negative for the whole range of collision angles 0 < θ < .

  5. Unified treatment of complex and real rotation-angular functions for two-center overlap integrals over arbitrary atomic orbitals

    CERN Document Server

    Guseinov, I I

    2010-01-01

    The new combined formulas have been established for the complex and real rotation-angular functions arising in the evaluation of two-center overlap integrals over arbitrary atomic orbitals in molecular coordinate system. These formulas can be useful in the study of different quantum mechanical problems in both the theory and practice of calculations dealing with atoms, molecules, nuclei and solids when the integer and noninteger n complex and real atomic orbitals basis sets are emploed. This work presented the development of our previous paper (I.I. Guseinov, Phys. Rev. A, 32 (1985) 1864).

  6. Bond-order conservation approach to chemisorption of polyatomic molecules: Effective partitioning of two-center bond energies

    Science.gov (United States)

    Shustorovich, Evgeny

    1988-10-01

    Within the bond-order conservation Morse-potential (BOC-MP) model of chemisorption, the analytic interrelations for diatomic admolecules (at low coverages) are rigorous. Here we extend these interrelations to treat polyatomic adsorbates partitioned into two effective fragments. We discuss a partitioning scheme involving the averaging of chemical structures representing reasonable limits (upper and lower) of two-center bond energies. It is shown that, by using this scheme, one can efficiently determine the preferred coordination modes of polyatomic adsorbates (monoversus dicoordination) and the preferred pathways of complex surface reactions (e.g. hydrogenation of CO and transformations of C 2 hydrocarbons). Relations to other theoretical approaches are briefly discussed.

  7. Nonrelativistic structure calculations of two-electron ions in a strongly coupled plasma environment

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, S.; Saha, J. K.; Mukherjee, T. K.

    2015-04-01

    In this work, the controversy between the interpretations of recent measurements on dense aluminum plasma created with the Linac coherent light source (LCLS) x-ray free electron laser (FEL) and the Orion laser has been addressed. In both kinds of experiments, heliumlike and hydrogenlike spectral lines are used for plasma diagnostics. However, there exist no precise theoretical calculations for He-like ions within a dense plasma environment. The strong need for an accurate theoretical estimate for spectral properties of He-like ions in a strongly coupled plasma environment leads us to perform ab initio calculations in the framework of the Rayleigh-Ritz variation principle in Hylleraas coordinates where an ion-sphere potential is used. An approach to resolve the long-drawn problem of numerical instability for evaluating two-electron integrals with an extended basis inside a finite domain is presented here. The present values of electron densities corresponding to the disappearance of different spectral lines obtained within the framework of an ion-sphere potential show excellent agreement with Orion laser experiments in Al plasma and with recent theories. Moreover, this method is extended to predict the critical plasma densities at which the spectral lines of H-like and He-like carbon and argon ions disappear. Incidental degeneracy and level-crossing phenomena are being reported for two-electron ions embedded in strongly coupled plasma. Thermodynamic pressure experienced by the ions in their respective ground states inside the ion spheres is also reported.

  8. Excitation energies with time-dependent density matrix functional theory: Singlet two-electron systems.

    Science.gov (United States)

    Giesbertz, K J H; Pernal, K; Gritsenko, O V; Baerends, E J

    2009-03-21

    Time-dependent density functional theory in its current adiabatic implementations exhibits three striking failures: (a) Totally wrong behavior of the excited state surface along a bond-breaking coordinate, (b) lack of doubly excited configurations, affecting again excited state surfaces, and (c) much too low charge transfer excitation energies. We address these problems with time-dependent density matrix functional theory (TDDMFT). For two-electron systems the exact exchange-correlation functional is known in DMFT, hence exact response equations can be formulated. This affords a study of the performance of TDDMFT in the TDDFT failure cases mentioned (which are all strikingly exhibited by prototype two-electron systems such as dissociating H(2) and HeH(+)). At the same time, adiabatic approximations, which will eventually be necessary, can be tested without being obscured by approximations in the functional. We find the following: (a) In the fully nonadiabatic (omega-dependent, exact) formulation of linear response TDDMFT, it can be shown that linear response (LR)-TDDMFT is able to provide exact excitation energies, in particular, the first order (linear response) formulation does not prohibit the correct representation of doubly excited states; (b) within previously formulated simple adiabatic approximations the bonding-to-antibonding excited state surface as well as charge transfer excitations are described without problems, but not the double excitations; (c) an adiabatic approximation is formulated in which also the double excitations are fully accounted for.

  9. Simulation of molecular Auger spectra using a two-electron Dyson propagator

    Energy Technology Data Exchange (ETDEWEB)

    Hori, Y.; Nishida, M.; Lim, F.H.; Ida, T., E-mail: ida@se.kanazawa-u.ac.jp; Mizuno, M.

    2016-02-15

    Highlights: • Auger electron spectra (AES) simulation using a new two-electron Dyson propagator. • Double ionization potentials can be accurately and efficiently computed. • The proposal method is useful for belonging peaks in AES of molecule. - Abstract: In order to simulate Auger electron spectra (AES), we propose the use of the two-electron Dyson propagator with the shifted denominator approximation (SD2). The double ionization potentials (DIPs) of molecules calculated using the SD2 method have shown good agreement with experimental data. This method can be used to calculate each DIP separately, and reducing the matrix dimensionality into that of only a two-hole configurations. We carried out AES simulations of water (H{sub 2}O), ethylene (C{sub 2}H{sub 4}), and formaldehyde (H{sub 2}CO) molecules and compared with the observed spectra. Furthermore Auger line shapes of glycine and hydrated glycine molecules were simulated, it found out that the peaks of nitrogen K-LL Auger were broadened due to hydration. From these results, we conclude that the SD2 method is very useful for the calculation of DIPs to investigate the properties of a double ionized molecule.

  10. Ion-acoustic solitons in negative ion plasma with two-electron temperature distributions

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, M. K.; Tiwari, R. S.; Chawla, J. K. [Department of Physics, University of Rajasthan, Jaipur-302004 (India)

    2012-06-15

    Ion-acoustic solitons in a warm positive and negative ion species with different masses, concentrations, and charge states with two electron temperature distributions are studied. Using reductive perturbation method, Korteweg de-Vries (KdV) and modified-KdV (m-KdV) equations are derived for the system. The soliton solution of the KdV and m-KdV equations is discussed in detail. It is found that if the ions have finite temperatures, then there exist two types of modes, namely slow and fast ion-acoustic modes. It is also investigated that the parameter determining the nature of soliton (i.e., whether the system will support compressive or rarefactive solitons) is different for slow and fast modes. For the slow mode, the parameter is the relative temperature of the two ion species; whereas for the fast mode, it is the relative concentration of the two ion species. At a critical concentration of negative ions, both compressive and rarefactive solitons coexist. The amplitude and width of the solitons are discussed in detail at critical concentration for m-KdV solitons. The effect of the relative temperature of the two-electron and cold-electron concentration on the characteristics of the solitons are also discussed.

  11. Two-electron electrochemical oxidation of quercetin and kaempferol changes only the flavonoid C-ring

    DEFF Research Database (Denmark)

    Jørgensen, Lars; Cornett, Claus; Justesen, Ulla

    1998-01-01

    Bulk electrolysis of the antioxidant flavonoids quercetin and kaempferol in acetonitrile both yield a single oxidation product in two-electron processes. The oxidation products are more polar than their parent compounds, with an increased molecular weight of 16g/mol, and were identified as 2......-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3 (2H)-benzofuranone and 2-(4-hydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone for quercetin and kaempferol, respectively. Two-electron oxidation of the parent flavonoid is suggested to yield a 3,4-flavandione with unchanged substitution pattern in the A- and B-ring, which...... may rearrange to form the substituted 3(2H)-benzofuranone through the chalcan-trione ring-chain tautomer. The acidity of the 3-OH group is suggested to determine the fate of the flavonoid phenoxyl radical originally formed by one-electron oxidation, as no well-defined oxidation product of luteolin...

  12. Observation of coherent population trapping in a V-type two-electron system

    CERN Document Server

    Singh, Alok K

    2015-01-01

    We observe coherent population trapping (CPT) in a two-electron atom---$^{174}$Yb---using the $\\rm {^1S_0,F=0} \\rightarrow {^3P_1,F'=1}$ transition. CPT is not possible for such a transition according to one-electron theory because the magnetic sublevels form a V-type system, but in a two-electron atom like Yb, the interaction of the electrons transforms the level structure into a $ \\Lambda $-type system, which allows the formation of a dark state and hence the observation of CPT. Since the two levels involved are degenerate, we use a magnetic field to lift the degeneracy. The single fluorescence dip then splits into five dips---the central unshifted one corresponds to coherent population oscillation, while the outer four are due to CPT. The linewidth of the CPT resonance is about 300 kHz and is limited by the natural linewidth of the excited state, which is to be expected because the excited state is involved in the formation of the dark state.

  13. Quantum Interferometry and Correlated Two-Electron Wave-Packet Observation in Helium

    CERN Document Server

    Ott, Christian; Raith, Philipp; Meyer, Kristina; Laux, Martin; Zhang, Yizhu; Hagstotz, Steffen; Ding, Thomas; Heck, Robert; Pfeifer, Thomas

    2012-01-01

    The concerted motion of two or more bound electrons governs atomic and molecular non-equilibrium processes and chemical reactions. It is thus a long-standing scientific dream to measure the dynamics of two bound correlated electrons in the quantum regime. Quantum wave packets were previously observed for single-active electrons on their natural attosecond timescales. However, at least two active electrons and a nucleus are required to address the quantum three-body problem. This situation is realized in the helium atom, but direct time-resolved observation of two-electron wave-packet motion remained an unaccomplished challenge. Here, we measure a 1.2-femtosecond quantum beating among low-lying doubly-excited states in helium to evidence a correlated two-electron wave packet. Our experimental method combines attosecond transient-absorption spectroscopy at unprecedented high spectral resolution (20 meV near 60 eV) with an intensity-tuneable visible laser field to couple the quantum states from the perturbative ...

  14. Quantum entanglement for two electrons in the excited states of helium-like systems

    CERN Document Server

    Lin, Yen-Chang

    2013-01-01

    The quantum entanglement for the two electrons in the excited states of the helium-like atom/ions is investigated using the two-electron wave functions constructed by the B-spline basis. As a measure of the spatial (electron-electron orbital) entanglement, the von Neumann entropy and linear entropy of the reduced density matrix are calculated for the 1s2s 1,3S excited states for systems with some selected Z values from Z=2 to Z=100. Results for the helium atom are compared with other available calculations. We have also investigated the entropies for these excited states when the nucleus charge is reduced from Z=2 to Z=1. At such a critical charge, all the singly-excited states of this system become unbound, and the linear entropies and the von Neumann entropies for the excited states are approaching 1/2 and 1, respectively, the limits for the entropies when one electron is bound to the nucleus, and the other being free.

  15. Charge transfer excitations from particle-particle random phase approximation-Opportunities and challenges arising from two-electron deficient systems.

    Science.gov (United States)

    Yang, Yang; Dominguez, Adriel; Zhang, Du; Lutsker, Vitalij; Niehaus, Thomas A; Frauenheim, Thomas; Yang, Weitao

    2017-03-28

    The particle-particle random phase approximation (pp-RPA) is a promising method for studying charge transfer(CT) excitations. Through a detailed analysis on two-electron deficient systems, we show that the pp-RPA is always able to recover the long-distance asymptotic -1/R trend for CT excitations as a result of the concerted effect between orbital energies and the pp-RPA kernel. We also provide quantitative results for systems with relatively short donor-acceptor distances. With conventional hybrid or range-separated functionals, the pp-RPA performs much better than time-dependent density functional theory (TDDFT), although it still gives underestimated results which are not as good as TDDFT with system-dependent tuned functionals. For pp-RPA, there remain three great challenges in dealing with CT excitations. First, the delocalized frontier orbitals in strongly correlated systems often lead to difficulty with self-consistent field convergence as well as an incorrect picture with about half an electron transferred. Second, the commonly used density functionals often underestimate the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (LUMO) for the two-electron deficient species, resulting in systems with delocalized orbitals. Third, the performance of pp-RPA greatly depends on the energy difference between the LUMO and a higher virtual orbital. However, the meaning of the orbital energies for higher virtual orbitals is still not clear. We also discuss the performance of an approximate pp-RPA scheme that uses density functional tight binding (pp-DFTB) as reference and demonstrate that the aforementioned challenges can be overcome by adopting suitable range-separated hybrid functionals. The pp-RPA and pp-DFTB are thus promising general approaches for describing charge transfer excitations.

  16. Linear and nonlinear optical absorption coefficients of two-electron spherical quantum dot with parabolic potential

    Science.gov (United States)

    Çakır, Bekir; Yakar, Yusuf; Özmen, Ayhan

    2015-02-01

    Linear and nonlinear absorption coefficients of two-electron spherical quantum dot (QD) with parabolic potential are investigated in this paper. Wave functions and energy eigenvalues of the 1s2, 1s1p, 1s1d and 1s1f electronic states have been computed by using an optimization approach, which is a combination of Quantum Genetic Algorithm (QGA) and Hartree-Fock Roothaan (HFR) method. It is found that the strength of S→P transition is stronger than P→D and D→F transitions. Also the peak positions and amplitudes of the absorption coefficients are sensitive to the electron spin. It should be noted that the peak positions and amplitudes of absorption coefficients are strongly dependent on the parabolic potential. Additionally, dot radius, impurity charge, incident optical intensity and relaxation time have a great influence on the linear and nonlinear absorption coefficients.

  17. Electronic structure of two-electron quantum dot with parabolic potential

    Science.gov (United States)

    Yakar, Yusuf; Çakır, Bekir; Özmen, Ayhan

    2015-01-01

    In this study, we investigate the parabolic potential effects on the ground and excited energy states of two-electron quantum dot with impurity inside an infinite spherical confining potential well. The wave function and energy eigenvalues were calculated using a modified variational optimization procedure based mainly on quantum genetic algorithm and Hartree-Fock-Roothaan method. The results show that the parabolic potential and impurity charge have a strong effect on the energy states and ionization energies. It is worth pointing out that as impurity charge increases, the ionization energy rises, but the ionization dot radius decreases. On the other hand, as parabolic potential increases, the ionization energy decreases, but the ionization dot radius increases.

  18. Linear and nonlinear optical absorption coefficients of two-electron spherical quantum dot with parabolic potential

    Energy Technology Data Exchange (ETDEWEB)

    Çakır, Bekir, E-mail: bcakir@selcuk.edu.tr [Physics Department, Faculty of Science, Selcuk University, Campus 42075, Konya (Turkey); Yakar, Yusuf, E-mail: yuyakar@yahoo.com [Physics Department, Faculty of Arts and Science, Aksaray University, Campus 68100, Aksaray (Turkey); Özmen, Ayhan [Physics Department, Faculty of Science, Selcuk University, Campus 42075, Konya (Turkey)

    2015-02-01

    Linear and nonlinear absorption coefficients of two-electron spherical quantum dot (QD) with parabolic potential are investigated in this paper. Wave functions and energy eigenvalues of the 1s{sup 2}, 1s1p, 1s1d and 1s1f electronic states have been computed by using an optimization approach, which is a combination of Quantum Genetic Algorithm (QGA) and Hartree–Fock Roothaan (HFR) method. It is found that the strength of S→P transition is stronger than P→D and D→F transitions. Also the peak positions and amplitudes of the absorption coefficients are sensitive to the electron spin. It should be noted that the peak positions and amplitudes of absorption coefficients are strongly dependent on the parabolic potential. Additionally, dot radius, impurity charge, incident optical intensity and relaxation time have a great influence on the linear and nonlinear absorption coefficients.

  19. Ground State of a Two-Electron Quantum Dot with a Gaussian Confining Potential

    Institute of Scientific and Technical Information of China (English)

    XIE Wen-Fang

    2006-01-01

    We investigate the ground-state properties of a two-dimensional two-electron quantum dot with a Gaussian confining potential under the influence of perpendicular homogeneous magnetic field. Calculations are carried out by using the method of numerical diagonalization of Hamiltonian matrix within the effective-mass approximation. A ground-state behaviour (singlet→triplet state transitions) as a function of the strength of a magnetic field has been found. It is found that the dot radius R of the Gaussian potential is important for the ground-state transition and the feature of ground-state for the Gaussian potential quantum dot (QD), and the parabolic potential QDs are similar when R is larger. The larger the quantum dot radius, the smaller the magnetic field for the singlet-triplet transition of the ground-state of two interacting electrons in the Gaussian quantum dot.

  20. Fast calculation of two-electron-repulsion integrals: a numerical approach

    CERN Document Server

    Lopes, Pedro E M

    2016-01-01

    An alternative methodology to evaluate two-electron-repulsion integrals based on numerical approximation is proposed. Computational chemistry has branched into two major fields with methodologies based on quantum mechanics and classical force fields. However, there are significant shadowy areas not covered by any of the available methods. Many relevant systems are often too big for traditional quantum chemical methods while being chemically too complex for classical force fields. Examples include systems in nanomedicine, studies of metalloproteins, etc. There is an urgent need to develop fast quantum chemical methods able to study large and complex systems. This work is a proof-of-concept on the numerical techniques required to develop accurate and computationally efficient algorithms for the fast calculation of electron-repulsion integrals, one of the most significant bottlenecks in the extension of quantum chemistry to large systems. All concepts and calculations were developed for the three-center integral...

  1. Ab-initio calculations on two-electron ions in strongly coupled plasma environment

    CERN Document Server

    Bhattacharyya, S; Mukherjee, T K

    2015-01-01

    In this work, the controversy between the interpretations of recent measurements on dense aluminum plasma created with Linac coherent light sources (LCLS) X-ray free electron laser (FEL) and Orion laser has been addressed. In both kind of experiments, helium-like and hydrogen-like spectral lines are used for plasma diagnostics . However, there exist no precise theoretical calculations for He-like ions within dense plasma environment. The strong need for an accurate theoretical estimates for spectral properties of He-like ions in strongly coupled plasma environment leads us to perform ab initio calculations in the framework of Rayleigh-Ritz variation principle in Hylleraas coordinates where ion-sphere potential is used. An approach to resolve the long-drawn problem of numerical instability for evaluating two-electron integrals with extended basis inside a finite domain is presented here. The present values of electron densities corresponding to disappearance of different spectral lines obtained within the fram...

  2. Exact equations of motion for natural orbitals of strongly driven two-electron systems

    CERN Document Server

    Rapp, J; Bauer, D

    2014-01-01

    Natural orbital theory is a computationally useful approach to the few and many-body quantum problem. While natural orbitals are known and applied since many years in electronic structure applications, their potential for time-dependent problems is being investigated only since recently. Correlated two-particle systems are of particular importance because the structure of the two-body reduced density matrix expanded in natural orbitals is known exactly in this case. However, in the time-dependent case the natural orbitals carry time-dependent phases that allow for certain time-dependent gauge transformations of the first kind. Different phase conventions will, in general, lead to different equations of motion for the natural orbitals. A particular phase choice allows us to derive the exact equations of motion for the natural orbitals of any (laser-) driven two-electron system explicitly, i.e., without any dependence on quantities that, in practice, require further approximations. For illustration, we solve th...

  3. Excitation, two-center interference and the orbital geometry in laser-induced nonsequential double ionization of diatomic molecules

    CERN Document Server

    Shaaran, T; Faria, C Figueira de Morisson

    2011-01-01

    We address the influence of the molecular orbital geometry and of the molecular alignment with respect to the laser-field polarization on laser-induced nonsequential double ionization of diatomic molecules for different molecular species, namely $\\mathrm{N}_2$ and $\\mathrm{Li}_2$. We focus on the recollision excitation with subsequent tunneling ionization (RESI) mechanism, in which the first electron, upon return, promotes the second electron to an excited state, from where it subsequently tunnels. We show that the electron-momentum distributions exhibit interference maxima and minima due to the electron emission at spatially separated centers. We provide generalized analytical expressions for such maxima or minima, which take into account $s$ $p$ mixing and the orbital geometry. The patterns caused by the two-center interference are sharpest for vanishing alignment angle and get washed out as this parameter increases. Apart from that, there exist features due to the geometry of the lowest occupied molecular ...

  4. Nonlocal Wigner-like correlation energy density functional: parametrization and tests on two-electron systems.

    Science.gov (United States)

    Katriel, Jacob; Bauer, Michael; Springborg, Michael; McCarthy, Shane P; Thakkar, Ajit J

    2007-07-14

    Reparametrization of Wigner's correlation energy density functional yields a very close fit to the correlation energies of the helium isoelectronic sequence. However, a quite different reparametrization is required to obtain an equally close fit to the isoelectronic sequence of Hooke's atom. In an attempt to avoid having to reparametrize the functional for different choices of the one-body potential, we propose a parametrization that depends on global characteristics of the ground-state electron density as quantified by scale-invariant combinations of expectation values of local one-body operators. This should be viewed as an alternative to the density-gradient paradigm, allowing one to introduce the nonlocal dependence of the density functional on the density in a possibly more effective way. Encouraging results are obtained for two-electron systems with one-body potentials of the form r(zeta) with zeta=-12,+12,1, which span the range between the Coulomb potential (zeta=-1) and the Hooke potential (zeta=2).

  5. Spin-orbit coupled two-electron Fermi gases of ytterbium atoms

    CERN Document Server

    Song, Bo; Zhang, Shanchao; Zou, Yueyang; Haciyev, Elnur; Huang, Wei; Liu, Xiong-Jun; Jo, Gyu-Boong

    2016-01-01

    We demonstrate the spin-orbit coupling (SOC) in a two-electron Fermi gas of $^{173}$Yb atoms by coupling two hyperfine ground states via the two-photon Raman transition. Due to the SU($N$) symmetry of the $^1$S$_0$ ground-state manifold which is insensitive to external magnetic field, an optical AC Stark effect is applied to split the ground spin states and separate an effective spin-1/2 subspace out from other hyperfine levels for the realization of SOC. With a momentum-dependent spin-orbit gap being suddenly opened by switching on the Raman transition, the dephasing of spin dynamics is observed, as a consequence of the momentum-dependent Rabi oscillations. Moreover, the momentum asymmetry of the spin-orbit coupled Fermi gas is also examined after projection onto the bare spin state and the corresponding momentum distribution is measured for different two-photon detuning. The realization of SOC for Yb fermions may open a new avenue to the study of novel spin-orbit physics with alkaline-earth-like atoms.

  6. Two-electron and one-photon transitions in highly charged nickel-like ions

    Institute of Scientific and Technical Information of China (English)

    Xie Lu-You; Dong Chen-Zhong; Jiang Jun; Wan Jian-Jie; Yan Jun

    2008-01-01

    This paper calculates the transition wavelengths and probabilities of the two-electron and one-photon(TEOP) transition from the(38-11/24dj)J:1,2 to(3p-13/24s1/2)J=1 and the(3p-11/2481/2)J=1 to(3d-1j4dj1)J=1,2 for highly charged Ni-like ions with atomic number Z in the range 47≤Z≤92.In the calculations,the multi-configuration Dirac-Fock method and corresponding program packages GRASP92 and REOS99 were used,and the relativistic effects,correlation effects and relaxation effects were considered systematically.It is found that the TEOP transitions are very sensitive to the correlation of electrons,and the probabilities will be enhanced sharply in some special Z regions along the isoelectronic sequence.The present TEOP transition wavelengths are compared with the available data from some previous publications,good agreement is obtained.

  7. Spin-orbit-coupled two-electron Fermi gases of ytterbium atoms

    Science.gov (United States)

    Song, Bo; He, Chengdong; Zhang, Shanchao; Hajiyev, Elnur; Huang, Wei; Liu, Xiong-Jun; Jo, Gyu-Boong

    2016-12-01

    We demonstrate all-optical implementation of spin-orbit coupling (SOC) in a two-electron Fermi gas of 173Yb atoms by coupling two hyperfine ground states with a narrow optical transition. Due to the SU (N ) symmetry of the S10 ground-state manifold which is insensitive to external magnetic fields, an optical ac Stark effect is applied to split the ground spin states, which exhibits a high stability compared with experiments on alkali-metal and lanthanide atoms, and separate out an effective spin-1/2 subspace from other hyperfine levels for the realization of SOC. The dephasing spin dynamics when a momentum-dependent spin-orbit gap is suddenly opened and the asymmetric momentum distribution of the spin-orbit-coupled Fermi gas are observed as a hallmark of SOC. The realization of all-optical SOC for ytterbium fermions should offer a route to a long-lived spin-orbit-coupled Fermi gas and greatly expand our capability of studying spin-orbit physics with alkaline-earth-metal-like atoms.

  8. Bovine lactoperoxidase - a versatile one- and two-electron catalyst of high structural and thermal stability.

    Science.gov (United States)

    Banerjee, Srijib; Furtmüller, Paul G; Obinger, Christian

    2011-02-01

    Lactoperoxidase (LPO), a member of the peroxidase-cyclooxygenase superfamily, is found in multiple human exocrine secretions and acts as a first line of defense against invading microorganisms by production of antimicrobial oxidants. Because of its ability to efficiently catalyze one- and two-electron oxidation reactions of inorganic and organic compounds, the heme peroxidase is widely used in food biotechnology, cosmetic industry, and diagnostic kits. In order to probe its structural integrity, conformational, and thermal stability, we have undertaken a comprehensive investigation by using complementary biophysical techniques including UV-Vis, circular dichroism and fluorescence spectroscopy as well as differential scanning calorimetry (DSC). The oxidoreductase exhibits a high chemical and thermal stability under oxidizing conditions but is significantly destabilized by addition of DTT. Due to its unique ester bonds between the prosthetic group and the protein as well as six intra-chain disulfides, unfolding of the central compact (-helical core occurs concomitantly with denaturation of the heme cavity. The corresponding enthalpic and entropic contributions to the free enthalpy of unfolding are presented. Together with spectroscopic data they will be discussed with respect to the known structure of bovine LPO and homologous myeloperoxidase as well as to its practical application.

  9. In vivo accuracy of two electronic foramen locators based on different operation systems.

    Science.gov (United States)

    Vasconcelos, Bruno Carvalho de; Araújo, Rebeca Bastos Rocha; Silva, Francisco Cláudio Fernandes Alves e; Luna-Cruz, Suyane Maria; Duarte, Marco Antonio Hungaro; Fernandes, Carlos Augusto de Oliveira

    2014-01-01

    The aim of this study was to compare in vivo the accuracy of two electronic foramen locators (EFLs) based on different operation systems - Root ZX and Propex II. Ten healthy adult patients needing premolar extractions due to orthodontic reasons participated in the study, providing a sample of 17 noncarious, non-restored, vital teeth (n= 24 canals). After coronal access preparation and cervical preflaring and prior to tooth extraction, the root canal length was measured alternating the two EFLs. All measurements were performed with K-files well fitted to the canal diameter at the level that each EFL indicated the apical foramen in their display (APEX or 0.0). The last K-file were fixed in place with cyanoacrylate, the tooth was extracted, and the apical 4 mm of each root were resected to measure the distance between the file tip and the apical foramen. The mean errors based on the absolute values of discrepancies were 0.30 ± 0.29 mm (Root ZX) and 0.32 ± 0.27 mm (Propex II). Analysis by the Wilcoxon test for paired samples showed no statistically significant differences between the electronic canal measurements performed with the EFLs (p=0.587). The apical foramen was accurately located in 75% (Root ZX) and 66.7% (Propex II) of the cases, considering a ±0.5 mm error margin, with no statistically significant difference by the chi-square test. Despite having different measurement mechanisms, both EFLs were capable of locating the apical foramen with high accuracy in vivo. Under the tested clinical conditions, Root ZX and Propex II displayed similar results.

  10. The occurrence and representation of three-centre two-electron bonds in covalent inorganic compounds.

    Science.gov (United States)

    Green, Jennifer C; Green, Malcolm L H; Parkin, Gerard

    2012-12-07

    Although compounds that feature 3-centre 2-electron (3c-2e) bonds are well known, there has been no previous effort to classify the interactions according to the number of electrons that each atom contributes to the bond, in a manner analogous to the classification of 2-centre 2-electron (2c-2e) bonds as either normal covalent or dative covalent. This article provides an extension to the Covalent Bond Classification (CBC) method by categorizing 3c-2e interactions according to whether (i) the two electrons are provided by one or by two atoms and (ii) the central bridging atom provides two, one, or zero electrons. Class I 3c-2e bonds are defined as those in which two atoms each contribute one electron to the 3-centre orbital, while Class II 3c-2e bonds are defined as systems in which the pair of electrons are provided by a single atom. Class I and Class II 3c-2e interactions can be denoted by structure-bonding representations that employ the "half-arrow" notation, which also provides a convenient means to determine the electron count at a metal centre. In contrast to other methods of electron counting, this approach provides a means to predict metal-metal bond orders that are in accord with theory. For example, compounds that feature symmetrically bridging carbonyl ligands do not necessarily have to be described as "ketone derivatives" because carbon monoxide can also serve as an electron pair donor to two metal centres. This bonding description also provides a simple means to rationalize the theoretical predictions of the absence of M-M bonds in molecules such as Fe(2)(CO)(9) and [CpFe(CO)(2)](2), which are widely misrepresented in textbooks as possessing M-M bonds.

  11. The case for synchrotron radiation studies of two-electron ions, atoms, and molecules at the ALS

    Science.gov (United States)

    Lubell, M. S.

    1995-05-01

    The theoretical description of two-electron systems has remained one of the most vexing problems in atomic physics since Bohr first introduced the concept of the quantized atom in 1913. Despite the diversity in approach, a degree of orthodoxy developed over the course of many years for characterizing and clasifying the discrete spectrum of two-electron states and for describing the features of the near-threshold double continuum. The last four years have seen this orthodoxy challenged both theoretically and experimentally. As a result, a strong need exists for additional experimental investigations of two-electron systems. We will first examine the long-held orthodox views and the recent challenges to them. We will then review the details and status of a new program at the Advanced Light Source (ALS) of Lawrence Berkeley Laboratory that has been developed by the NAU8 Collaboration to address this need.

  12. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  13. Subgingival topical doxycycline versus mechanical debridement for supportive periodontal therapy: a single blind randomized controlled two-center study.

    Science.gov (United States)

    Eickholz, Peter; Kim, Ti-Sun; Schacher, Beate; Reitmeir, Peter; Bürklin, Thomas; Ratka-Krüger, Petra

    2005-12-01

    To evaluate the clinical effects of topical subgingival application of a doxycycline gel compared to conventional mechanical debridement in supportive periodontal therapy. 37 patients with residual or recurring periodontitis after systematic periodontal treatment at two centers (Heidelberg, Frankfurt) participated in this study. They had to exhibit at least one single-rooted tooth with either a probing depth (PPD) = 5 mm and bleeding-on-probing (BOP) or with PPD > or = 6 mm. The patients were randomly assigned to one of the two different treatment regimes: DOXY (exclusively subgingival application of a 14% doxycycline gel) or SRP (scaling and root planing with a sonic scaler). Clinical examinations (plaque index [P1I], PPD, vertical relative attachment level [RAL-V], gingival index [GI]) were performed before, 3, and 6 months after therapy. In 37 patients (19 female), aged 30-76 years with a total of 168 teeth were treated (DOXY: 79; SRP: 89). Six months after therapy, both groups exhibited statistically significant (PDOXY: -1.43 +/- 0.22 mm; SRP: -1.14 +/- 0.18 mm) and gains of RAL-V (DOXY: 0.79 +/- 0.22 mm; SRP: 0.72 +/- 0.19 mm). Multilevel regression analyses, considering the therapy of different numbers of teeth in different patients, failed to show statistically significant differences concerning PPD reduction and RAL-V gain between both therapies (DOXY/SRP). For both therapies, PPD reduction was significantly better in deeper pockets (PPD > or = 7 mm) than in shallow pockets (PPD: 5-6 mm).

  14. Characterization of the energy response and backscatter contribution for two electronic personal dosimeter models.

    Science.gov (United States)

    Meier, Joseph; Kappadath, S Cheenu

    2015-11-08

    We characterized the energy response of personal dose equivalent (Hp(10) in mrem) and the contribution of backscatter to the readings of two electronic personal dosimeter (EPD) models with radionuclides commonly used in a nuclear medicine clinic. The EPD models characterized were the RADOS RAD-60R, and the SAIC PD-10i. The experimental setup and calculation of EPD energy response was based on ANSI/HPS N13.11-2009. Fifteen RAD-60R and 2 PD-10i units were irradiated using (99m)Tc, (131)I, and (18)F radionuclides with emission energies at 140 keV, 364 keV, and 511 keV, respectively. At each energy, the EPDs output in Hp(10) [mrem] were recorded with 15 inch thick PMMA to simulate backscatter form the torso. Simultaneous free-in-air exposure rate measurements were also performed using two Victoreen ionization survey meters to calculate the expected EPD Hp(10) values per ANSI/HPS N13.11-2009. The energy response was calculated by taking the ratio of the EPD Hp(10) readings with the expected Hp(10) readings and a two-tailed z-test was used to determine the significance of the ratio deviating away from unity. The contribution from backscatter was calculated by taking the ratio of the EPD Hp(10) readings with and without backscatter material. A paired, two-tailed t-test was used to determine the significance of change in EPD Hp(10) readings. The RAD-60R mean energy response at 140 keV was 0.85, and agreed to within 5% and 11% at 364 and 511 keV, respectively. The PD-10i mean energy response at 140 keV was 1.20, and agreed to within 5% at 364 and 511 keV, respectively. On average, in the presence of acrylic, RAD-60R values increased by 32%, 12%, and 14%, at 140, 364, and 511 keV, respectively; all increases were statistically significant. The PD-10i increased by 25%, 19%, and 10% at 140 keV, 364 keV, and 511 keV, respectively; however, only the 140 keV measurement was statistically significant. Although both EPD models performed within the manufacturers' specifications of

  15. Highly Efficient and Scalable Compound Decomposition of Two-Electron Integral Tensor and Its Application in Coupled Cluster Calculations.

    Science.gov (United States)

    Peng, Bo; Kowalski, Karol

    2017-09-12

    The representation and storage of two-electron integral tensors are vital in large-scale applications of accurate electronic structure methods. Low-rank representation and efficient storage strategy of integral tensors can significantly reduce the numerical overhead and consequently time-to-solution of these methods. In this work, by combining pivoted incomplete Cholesky decomposition (CD) with a follow-up truncated singular vector decomposition (SVD), we develop a decomposition strategy to approximately represent the two-electron integral tensor in terms of low-rank vectors. A systematic benchmark test on a series of 1-D, 2-D, and 3-D carbon-hydrogen systems demonstrates high efficiency and scalability of the compound two-step decomposition of the two-electron integral tensor in our implementation. For the size of the atomic basis set, Nb, ranging from ∼100 up to ∼2,000, the observed numerical scaling of our implementation shows [Formula: see text] versus [Formula: see text] cost of performing single CD on the two-electron integral tensor in most of the other implementations. More importantly, this decomposition strategy can significantly reduce the storage requirement of the atomic orbital (AO) two-electron integral tensor from [Formula: see text] to [Formula: see text] with moderate decomposition thresholds. The accuracy tests have been performed using ground- and excited-state formulations of coupled cluster formalism employing single and double excitations (CCSD) on several benchmark systems including the C60 molecule described by nearly 1,400 basis functions. The results show that the decomposition thresholds can be generally set to 10(-4) to 10(-3) to give acceptable compromise between efficiency and accuracy.

  16. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  17. Adiabatic potential energy curves of long-range Rydberg molecules: Two-electron R-matrix approach

    CERN Document Server

    Tarana, Michal

    2016-01-01

    We introduce a computational method developed for study of long-range molecular Rydberg states of such systems that can be approximated by two electrons in a model potential of the atomic cores. Only diatomic molecules are considered. The method is based on a two-electron \\rmath approach inside a sphere centered on one of the atoms. The wave function is then connected to a Coulomb region outside the sphere via multichannel version of the Coulomb Green's function. This approach is put into a test by its application to a study of Rydberg states of the hydrogen molecule for internuclear distances $R$ from 20 to 400 bohrs and energies corresponding to $n$ from 3 to 22. The results are compared with previous quantum chemical calculations (lower quantum numbers $n$) and computations based on contact potential models (higher quantum numbers $n$).

  18. Superlinear scaling in master-slave quantum chemical calculations using in-core storage of two-electron integrals.

    Science.gov (United States)

    Fossgård, Eirik; Ruud, Kenneth

    2006-02-01

    We describe the implementation of a parallel, in-core, integral-direct Hartree-Fock and density functional theory code for the efficient calculation of Hartree-Fock wave functions and density functional theory. The algorithm is based on a parallel master-slave algorithm, and the two-electron integrals calculated by a slave are stored in available local memory. To ensure the greatest computational savings, the master node keeps track of all integral batches stored on the different slaves. The code can reuse undifferentiated two-electron integrals both in the wave function optimization and in the evaluation of second-, third-, and fourth-order molecular properties. Superlinear scaling is achieved in a series of test examples, with speedups of up to 55 achieved for calculations run on medium-sized molecules on 16 processors with respect to the time used on a single processor.

  19. First principles calculations of double ionization energy spectra and two-electron distribution function using T-matrix theory

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Yoshifumi [Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan); Computational Materials Science Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)], E-mail: NOGUCHI.Yoshifumi@nims.go.jp; Ishii, Soh; Ohno, Kaoru [Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)

    2007-05-15

    Short-range electron correlation plays a very important role in small systems and significantly affects the double ionization energy (DIE) spectra and the two-electron distribution functions of a CO molecule, for example. In our calculations, the local density approximation (LDA) of the density functional theory is chosen as a starting point, the GW approximation (GWA) is performed in a next step, and finally the Bethe-Salpeter equation for the T-matrix, describing the particle-particle ladder diagrams up to the infinite order, is solved via the eigenvalue problem. The calculated DIE spectra, which are directly given by the eigenvalues, reflect the short-range electron correlation and are in good agreement with the experiment. We confirm that the Coulomb hole appears in the two-electron distribution function constructed from the eigenfunction.

  20. Hooke's Atom in an Arbitrary External Electric Field: Analytical Solutions of Two-Electron Problem by Path Integral Approach

    Institute of Scientific and Technical Information of China (English)

    CAI Liang; ZHANG Ping; YANG Tao; PAN Xiao-Yin

    2011-01-01

    By using the path integral approach, we investigate the problem of Hooke's atom (two electrons interacting with Coulomb potential in an external harmonic-oscillator potential) in an arbitrary time-dependent electric field. For a certain infinite set of discrete oscillator frequencies, we obtain the analytical solutions. The ground state polarization of the atom is then calculated. The same result is also obtained through linear response theory.

  1. Comments to a series of works by V.K. Mukhomorov on the theory of a continuum polaron and two-center bipolaron (axially symmetrical quasimolecular dimer)

    OpenAIRE

    2013-01-01

    Some critical remarks are made regarding a series of works by V.K. Mukhomorov dealing with polarons and oscillatory and rotational spectrum of a large-radius bipolaron near a subsidiary minimum corresponding to its two-center configuration. It is shown that V.K. Mukhomorov's conclusion that by varying the bipolaron functional one should look for a constrained rather than absolute minimum is erroneous. Consideration of interelectronic correlations corresponding to a direct dependence of the wa...

  2. Coulomb Repulsion Effect in Two-electron Non-adiabatic Tunneling through a One-level redox Molecule

    DEFF Research Database (Denmark)

    Medvedev, Igor M.; Kuznetsov, Alexander M.; Ulstrup, Jens

    2009-01-01

    is representative of electrochemical scanning tunneling microscopy or a pair of electrochemical nanoscale electrodes. The two-electron transfer molecular system also represents redox molecules with three electrochemically accessible oxidation states, rather than only two states such as comprehensively studied...... conductance/bias voltage correlation can have up to four peaks even for a single-level redox molecule. The peak position, height, and width are determined by the oxidized and reduced states of both the ionization and affinity levels of the molecule and depend crucially on the Debye screening of the electric...

  3. S-matrix theory of two-electron momentum distribution produced by double ionization in intense laser fields.

    Science.gov (United States)

    Becker, A; Faisal, F

    2001-03-26

    Recently observed momentum distribution of doubly charged recoil-ions of atoms produced by femtosecond infrared laser pulses is analyzed using the so-called intense-field many-body S-matrix theory. Observed characteristics of the momentum distributions, parallel and perpendicular to the polarization axis, are reproduced by the theory. It is shown that correlated energy-sharing between the two electrons in the intermediate state and their 'Volkov-dressing' in the final state, can explain the origin of these characteristics.

  4. Excitation and charge transfer in He/sup +/ + H collisions. A molecular approach including two-electron translation factors

    Energy Technology Data Exchange (ETDEWEB)

    Errea, L.F.; Mendez, L.; Riera, A.

    1983-06-01

    In a previous paper we have pointed out that the common-translation-factor (CTF) method is the only one which, at present, and within the framework of the molecular model of atomic collisions, can be shown to be both convergent and computationally fast, even for many-electron systems. In this Communication we check that this second statement is correct, presenting, for the first time, a molecular calculation involving two-electron translation factors, for He/sup +/ + H collisions. A careful study of the sensitivity of the calculated cross sections to the choice of the CTF is performed, and conclusions on that sensitivity are drawn, for several types of processes.

  5. Spectroscopic Studies of a Water-soluble Derivative of Hypocrellin A and Its One- and Two-Electron Reduction Products

    Institute of Scientific and Technical Information of China (English)

    胡义镇; 安静仪; 蒋丽金

    1994-01-01

    In this study the spectroscopic characteristics of a water-soluble derivative of hypocrellin A (HA), 14-dehydroxy-15-deacetyl-hypocrellin A-13-sulfonate(13-SO3Na-DDHA),and its one- and two-electron reduction products have been investigated. From the changes in absorbance with pH it was observed that the two phenolic hydroxy groups at C-3 and C-10 positions of 13-SO3Na-DDHA or HA dissociated stepwise with increase of pH values. The pKa values for 13-SO3Na-DDHA and HA were determined using an effective method established in this study. Attempts were also made to use absorption and ESR spectroscopies to study the photoreduction of 13-SO3Na-DDHA. It was found that 13-SO3Na-DDHA was directly reduced to its two-electron reduction product in buffered aqueous solution (pH 7. 7). However, in DMF-buffer (1 :1/ v : v,pH 7. 7), it proceeded with one-electron reduction to generate its semiquinone radical anions. The semiquinone radical anions decayed according to second-order kinetics. indicating that the terminatio

  6. Two-electron R-matrix approach to calculations of potential-energy curves of long-range Rydberg molecules

    Science.gov (United States)

    Tarana, Michal; Čurík, Roman

    2016-05-01

    We introduce a computational method developed for study of long-range molecular Rydberg states of such systems that can be approximated by two electrons in a model potential of the atomic cores. The method is based on a two-electron R-matrix approach inside a sphere centered on one of the atoms. The wave function is then connected to a Coulomb region outside the sphere via a multichannel version of the Coulomb Green's function. This approach is applied to a study of Rydberg states of Rb2 for internuclear separations R from 40 to 320 bohrs and energies corresponding to n from 7 to 30. We report bound states associated with the low-lying 3Po resonance and with the virtual state of the rubidium atom that turn into ion-pair-like bound states in the Coulomb potential of the atomic Rydberg core. The results are compared with previous calculations based on single-electron models employing a zero-range contact-potential and short-range modele potential. Czech Science Foundation (Project No. P208/14-15989P).

  7. Two-electron reductive carbonylation of terminal uranium(V) and uranium(VI) nitrides to cyanate by carbon monoxide.

    Science.gov (United States)

    Cleaves, Peter A; King, David M; Kefalidis, Christos E; Maron, Laurent; Tuna, Floriana; McInnes, Eric J L; McMaster, Jonathan; Lewis, William; Blake, Alexander J; Liddle, Stephen T

    2014-09-22

    Two-electron reductive carbonylation of the uranium(VI) nitride [U(Tren(TIPS))(N)] (2, Tren(TIPS)=N(CH2CH2NSiiPr3)3) with CO gave the uranium(IV) cyanate [U(Tren(TIPS))(NCO)] (3). KC8 reduction of 3 resulted in cyanate dissociation to give [U(Tren(TIPS))] (4) and KNCO, or cyanate retention in [U(Tren(TIPS))(NCO)][K(B15C5)2] (5, B15C5=benzo-15-crown-5 ether) with B15C5. Complexes 5 and 4 and KNCO were also prepared from CO and the uranium(V) nitride [{U(Tren(TIPS))(N)K}2] (6), with or without B15C5, respectively. Complex 5 can be prepared directly from CO and [U(Tren(TIPS))(N)][K(B15C5)2] (7). Notably, 7 reacts with CO much faster than 2. This unprecedented f-block reactivity was modeled theoretically, revealing nucleophilic attack of the π* orbital of CO by the nitride with activation energy barriers of 24.7 and 11.3 kcal mol(-1) for uranium(VI) and uranium(V), respectively. A remarkably simple two-step, two-electron cycle for the conversion of azide to nitride to cyanate using 4, NaN3 and CO is presented.

  8. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  9. Comment on Unified treatment for two-center one-electron molecular integrals over Slater-type orbitals with integer and noninteger principal quantum numbers

    OpenAIRE

    Guseinov, I. I.

    2005-01-01

    In a recent paper Ozdogan (Z. Naturforsch, 59a(2004)743) published formulas for evaluating the two-center overlap and nuclear attraction integrals over integer and noninteger Slater type orbitals. The purpose of this article is to point out that the same formulas have previously been established by Guseinov et al. (J.Mol.Model.,8(2002)272) by using the same method. As we demonstrated in our Comment (Int.J.Quantum Chem., 91(2003)62), the expansion formula for the product of two normalized asso...

  10. Pd(II)-catalyzed cascade Wacker-Heck reaction: chemoselective coupling of two electron-deficient reactants.

    Science.gov (United States)

    Silva, Franck; Reiter, Maud; Mills-Webb, Rebecca; Sawicki, Marcin; Klär, Daniel; Bensel, Nicolas; Wagner, Alain; Gouverneur, Véronique

    2006-10-27

    A novel palladium(II)-catalyzed oxy-carbopalladation process was developed allowing for the orchestrated union of hydroxy ynones with ethyl acrylate, two electron-deficient reactants. With beta-hydroxy ynones, this cascade Wacker-Heck process gave access to highly functionalized tri- or tetrasubstituted dihydropyranones featuring an unusual dienic system. For diastereomerically pure and for enantioenriched beta-hydroxyynones, these reactions proceed without affecting the stereochemical integrity of the existing stereocenters. In addition, tetrasubstituted furanones can be prepared when alpha-hydroxyynones and ethyl acrylate are used as starting materials. The dihydropyranones and furanones obtained upon cyclization are novel compounds, but structurally related carbohydrate derivatives featuring a similar dienic system have been used as starting materials for the construction of polyannulated products, suggesting that these cascade Pd(II)-mediated oxidative heterocyclizations are of value for various synthetic applications.

  11. Modern methods for calculations of photoionization and electron impact ionization of two-electron atoms and molecules

    CERN Document Server

    Serov, Vladislav V; Sergeeva, Tatiana A; Vinitsky, Sergue I

    2012-01-01

    A review of some recently developed methods of calculating multiple differential cross-sections of photoionization and electron impactionization of atoms and molecules having two active electrons is presented. The methods imply original approaches to calculating three-particle Coulomb wave functions. The external complex scaling method and the formalism of the Schroedinger equation with a source in the right-hand side are considered. Efficiency of the time-dependent approaches to the scattering problem, such as the paraxial approximation and the time-dependent scaling, is demonstrated. An original numerical method elaborated by the authors for solving the 6D Schroedinger equation for an atom with two active electrons, based on the Chang-Fano transformation and the discrete variable representation, is formulated. Basing on numerical simulations, the threshold behavior of angular distributions of two-electron photoionization of the negative hydrogen ion and helium atom, and multiple differential cross-sections ...

  12. Effect of Temperature and Pressure on Correlation Energy in a Triplet State of a Two Electron Spherical Quantum Dot

    Directory of Open Access Journals (Sweden)

    A. Rejo Jeice

    2013-09-01

    Full Text Available The combined effect of hydrostatic pressure and temperature on correlation energy in a triplet state of two electron spherical quantum dot with square well potential is computed. The result is presented taking GaAs dot as an example. Our result shows the correlation energies are inegative in the triplet state contrast to the singlet state ii it increases with increase in pressure  iiifurther decreases due to the application  of temperature iv it approaches zero as dot size approaches infinity and v it contribute 10% decrement in total confined energy to the narrow dots. All the calculations have been carried out with finite models and the results are compared with existing literature.

  13. [Cu13 {S2 CN(n) Bu2 }6 (acetylide)4 ](+) : A Two-Electron Superatom.

    Science.gov (United States)

    Chakrahari, Kiran Kumarvarma; Liao, Jian-Hong; Kahlal, Samia; Liu, Yu-Chiao; Chiang, Ming-Hsi; Saillard, Jean-Yves; Liu, C W

    2016-11-14

    The first structurally characterized copper cluster with a Cu13 centered cuboctahedral arrangement, a model of the bulk copper fcc structure, was observed in [Cu13 (S2 CN(n) Bu2 )6 (C≡CR)4 ](PF6 ) (R=C(O)OMe, C6 H4 F) nanoclusters. Four of the eight triangular faces of the cuboctahedron are capped by acetylide groups in μ3  fashion, and each of the six square faces is bridged by a dithiolate ligand in μ2 ,μ2 fashion, which leads to a truncated tetrahedron of twelve sulfur atoms. DFT calculations are fully consistent with the description of these Cu13 clusters as two-electron superatoms, that is, a [Cu13 ](11+) core passivated by ten monoanionic ligands, with an a1 HOMO containing two 1S jellium electrons.

  14. Role of two-electron processes in the excitation-ionization of lithium atoms by fast ion impact

    CERN Document Server

    Kirchner, T; Gulyás, L

    2015-01-01

    We study excitation and ionization in the 1.5 MeV/amu O$^{8+}$-Li collision system, which was the subject of a recent reaction-microscope-type experiment [Fischer \\textit{et al.}, Phys. Rev. Lett. \\textbf{109}, 113202 (2012)]. Starting from an independent-electron model based on determinantal wave functions and using single-electron basis generator method and continuum distorted-wave with eikonal initial-state calculations we show that pure single ionization of a lithium $K$-shell electron is too weak a process to explain the measured single differential cross section. Rather, our analysis suggests that two-electron excitation-ionization processes occur and have to be taken into account when comparing with the data. Good agreement is obtained only if we replace the independent-electron calculation by an independent-event model for one of the excitation-ionization processes and also take a shake-off process into account.

  15. Compact two-electron wave function for bond dissociation and Van der Waals interactions: A natural amplitude assessment

    Energy Technology Data Exchange (ETDEWEB)

    Giesbertz, Klaas J. H. [Theoretical Chemistry, Faculty of Exact Sciences, VU University, De Boelelaan 1083, 1081 HV Amsterdam (Netherlands); Leeuwen, Robert van [Department of Physics, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Survontie 9, Jyväskylä (Finland)

    2014-05-14

    Electron correlations in molecules can be divided in short range dynamical correlations, long range Van der Waals type interactions, and near degeneracy static correlations. In this work, we analyze for a one-dimensional model of a two-electron system how these three types of correlations can be incorporated in a simple wave function of restricted functional form consisting of an orbital product multiplied by a single correlation function f (r{sub 12}) depending on the interelectronic distance r{sub 12}. Since the three types of correlations mentioned lead to different signatures in terms of the natural orbital (NO) amplitudes in two-electron systems, we make an analysis of the wave function in terms of the NO amplitudes for a model system of a diatomic molecule. In our numerical implementation, we fully optimize the orbitals and the correlation function on a spatial grid without restrictions on their functional form. Due to this particular form of the wave function, we can prove that none of the amplitudes vanishes and moreover that it displays a distinct sign pattern and a series of avoided crossings as a function of the bond distance in agreement with the exact solution. This shows that the wave function ansatz correctly incorporates the long range Van der Waals interactions. We further show that the approximate wave function gives an excellent binding curve and is able to describe static correlations. We show that in order to do this the correlation function f (r{sub 12}) needs to diverge for large r{sub 12} at large internuclear distances while for shorter bond distances it increases as a function of r{sub 12} to a maximum value after which it decays exponentially. We further give a physical interpretation of this behavior.

  16. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  17. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  18. Emergency thoracotomies: Two center study

    Directory of Open Access Journals (Sweden)

    Sameh Ibrahim Sersar

    2013-01-01

    Full Text Available Introduction and Aim: Emergency thoracotomy is performed either immediately at the scene of injury, in the emergency department or in the operating room. It aims to evacuate the pericardial tamponade, control the haemorrhage, to ease the open cardiac massage and to cross-clamp the descending thoracic aorta to redistribute blood flow and maybe to limit sub-diaphragmatic haemorrhage, bleeding and iatrogenic injury are the common risk factors. We aimed to review our experience in the field of emergency thoracotomies, identify the predictors of death, analyze the early results, detect the risk factors and asses the mortalities and their risk factors. Patients and Methods: Our hospital records of 197 patients who underwent emergency thoracotomy were reviewed. We retrospectively analyzed a piece of the extensive experience of the Mansoura University Hospitals and Mansoura Emergency Hospital; Egypt and Saudi German Hospitals; Jeddah in the last 12 years in the management of trauma cases for whom emergency thoracotomy. The aim was to analyse the early results of such cases and to detect the risk factors of dismal prognosis. Results: Our series included 197 cases of emergency thoractomies in Mansoura; Egypt and SGH; Jeddah; KSA in the last 12 years. The mean age of the victims was 28 years and ranged between 5 and 62 years. Of the 197 patients with emergency thoracotomy, the indications were both penetrating and blunt chest trauma, iatrogenic and postoperative hemodynamito a surgical cause. The commonest indication was stab heart followed by traumatic diaphragmatic ruptures. Conclusion: The results of emergency thoracotomy in our series were cooping with the results of other reports, mainly due to our aggressive measures to achieve rapid stabilization of the hemodynamic condition. We emphasize the importance of emergency medicine education programs on rapid diagnosis of traumatic injuries with early intervention, and adequate hemodynamic and respiratory support. Emergency thoracotomy has an important role in emergency big volume hospitals and can save a lot of lives. Outcome can be improved by increasing the learning curve and the integrated cooperation of the emergency and surgical teams.

  19. FAD semiquinone stability regulates single- and two-electron reduction of quinones by Anabaena PCC7119 ferredoxin:NADP+ reductase and its Glu301Ala mutant.

    Science.gov (United States)

    Anusevicius, Zilvinas; Miseviciene, Lina; Medina, Milagros; Martinez-Julvez, Marta; Gomez-Moreno, Carlos; Cenas, Narimantas

    2005-05-15

    Flavoenzymes may reduce quinones in a single-electron, mixed single- and two-electron, and two-electron way. The mechanisms of two-electron reduction of quinones are insufficiently understood. To get an insight into the role of flavin semiquinone stability in the regulation of single- vs. two-electron reduction of quinones, we studied the reactions of wild type Anabaena ferredoxin:NADP(+)reductase (FNR) with 48% FAD semiquinone (FADH*) stabilized at the equilibrium (pH 7.0), and its Glu301Ala mutant (8% FADH* at the equilibrium). We found that Glu301Ala substitution does not change the quinone substrate specificity of FNR. However, it confers the mixed single- and two-electron mechanism of quinone reduction (50% single-electron flux), whereas the wild type FNR reduces quinones in a single-electron way. During the oxidation of fully reduced wild type FNR by tetramethyl-1,4-benzoquinone, the first electron transfer (formation of FADH*) is about 40 times faster than the second one (oxidation of FADH*). In contrast, the first and second electron transfer proceeded at similar rates in Glu301Ala FNR. Thus, the change in the quinone reduction mechanism may be explained by the relative increase in the rate of second electron transfer. This enabled us to propose the unified scheme of single-, two- and mixed single- and two-electron reduction of quinones by flavoenzymes with the central role of the stability of flavin/quinone ion-radical pair.

  20. Pairing and unpairing electron densities in organic systems: Two-electron three center through space and through bonds interactions

    Energy Technology Data Exchange (ETDEWEB)

    Lobayan, Rosana M., E-mail: rmlb@exa.unne.edu.ar [Departamento de Física, Facultad de Ciencias Exactas, Naturales y Agrimensura, Universidad Nacional del Nordeste, 3400, Corrientes (Argentina); Bochicchio, Roberto C., E-mail: rboc@df.uba.ar [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, and IFIBA, CONICET, Ciudad Universitaria, 1428, Buenos Aires (Argentina)

    2014-05-07

    Two-electron three-center bonding interactions in organic ions like methonium (CH{sub 5}{sup +}), ethonium (C{sub 2}H{sub 7}{sup +}), and protonated alkanes n−C{sub 4}H{sub 11}{sup +} isomers (butonium cations) are described and characterized within the theoretical framework of the topological analysis of the electron density decomposition into its effectively paired and unpaired contributions. These interactions manifest in some of this type of systems as a concentration of unpaired electron cloud around the bond paths, in contrast to the well known paradigmatic boron hydrids in which it is not only concentrated close to the atomic nucleus and the bond paths but out of them and over the region defined by the involved atoms as a whole. This result permits to propose an attempt of classification for these interactions based in such manifestations. In the first type, it is called as interactions through bonds and in the second type as interactions through space type.

  1. Ion-acoustic Gardner Solitons in electron-positron-ion plasma with two-electron temperature distributions

    Science.gov (United States)

    Rehman, Momin A.; Mishra, M. K.

    2016-01-01

    The ion-acoustic solitons in collisionless plasma consisting of warm adiabatic ions, isothermal positrons, and two temperature distribution of electrons have been studied. Using reductive perturbation method, Korteweg-de Vries (K-dV), the modified K-dV (m-KdV), and Gardner equations are derived for the system. The soliton solution of the Gardner equation is discussed in detail. It is found that for a given set of parameter values, there exists a critical value of β=Tc/Th, (ratio of cold to hot electron temperature) below which only rarefactive KdV solitons exist and above it compressive KdV solitons exist. At the critical value of β, both compressive and rarefactive m-KdV solitons co-exist. We have also investigated the soliton in the parametric regime where the KdV equation is not valid to study soliton solution. In this region, it is found that below the critical concentration the system supports rarefactive Gardner solitons and above it compressive Gardner solitons are found. The effects of temperature ratio of two-electron species, cold electron concentration, positron concentration on the characteristics of solitons are also discussed.

  2. Strong-field absorption and emission of radiation in two-electron systems calculated with time-dependent natural orbitals

    CERN Document Server

    Brics, M; Bauer, D

    2016-01-01

    Recently introduced time-dependent renormalized-natural-orbital theory (TDRNOT) is based on the equations of motion for the so-called natural orbitals, i.e., the eigenfunctions of the one-body reduced density matrix. Exact TDRNOT can be formulated for any time-dependent two-electron system in either spin configuration. In this paper, the method is tested against high-order harmonic generation (HHG) and Fano profiles in absorption spectra with the help of a numerically exactly solvable one-dimensional model He atom, starting from the spin-singlet ground state. Such benchmarks are challenging because Fano profiles originate from transitions involving autoionizing states, and HHG is a strong-field phenomenon well beyond linear response. TDRNOT with just one natural orbital per spin in the helium spin-singlet case is equivalent to time-dependent Hartree-Fock or time-dependent density functional theory (TDDFT) in exact exchange-only approximation. It is not unexpected that TDDFT fails in reproducing Fano profiles ...

  3. Time-dependent reduced density matrix functional theory applied to laser-driven, correlated two-electron dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Brics, Martins; Kapoor, Varun; Bauer, Dieter [Institut fuer Physik, Universitaet Rostock, 18051 Rostock (Germany)

    2013-07-01

    Time-dependent density functional theory (TDDFT) with known and practicable exchange-correlation potentials does not capture highly correlated electron dynamics such as single-photon double ionization, autoionization, or nonsequential ionization. Time-dependent reduced density matrix functional theory (TDRDMFT) may remedy these problems. The key ingredients in TDRDMFT are the natural orbitals (NOs), i.e., the eigenfunctions of the one-body reduced density matrix (1-RDM), and the occupation numbers (OCs), i.e., the respective eigenvalues. The two-body reduced density matrix (2-RDM) is then expanded in NOs, and equations of motion for the NOs can be derived. If the expansion coefficients of the 2-RDM were known exactly, the problem at hand would be solved. In practice, approximations have to be made. We study the prospects of TDRDMFT following a top-down approach. We solve the exact two-electron time-dependent Schroedinger equation for a model Helium atom in intense laser fields in order to study highly correlated phenomena such as the population of autoionizing states or single-photon double ionization. From the exact wave function we calculate the exact NOs, OCs, the exact expansion coefficients of the 2-RDM, and the exact potentials in the equations of motion. In that way we can identify how many NOs and which level of approximations are necessary to capture such phenomena.

  4. On the Evaluation of Two-Center Overlap Integrals over Integer and Noninteger -Center Overlap Integrals over Integer and Noninteger n-Slater-Type Orbitals

    Institute of Scientific and Technical Information of China (English)

    T. Ozdogan, M. Orbay; S. Gümüs

    2002-01-01

    In this study, two-center overlap integrals over Slater-type orbitals (STOs) with integer and noninteger principal quantum numbers in unaligned coordinate systems have been calculated using formulas for overlap integrals in aligned coordinate systems obtained by the author's previous work (T. Ozdogan and M. Orbay, Int. J. Quant. Chem. 87(2002) 15). The obtained results for integer case have been found to be in excellent agreement with the prior literature.On the other hand, to the best of authors knowledge, because of the scarcity of the literatures on the use of noninteger n-STOs in unaligned coordinate systems, the results for noninteger case have been tested with the limit of integer case,and good agreement has been obtained too.

  5. Electron-electron interaction in strong electromagnetic fields: the two-electron contribution to the ground-state energy in He-like uranium.

    Science.gov (United States)

    Gumberidze, A; Stöhlker, Th; Banaś, D; Beckert, K; Beller, P; Beyer, H F; Bosch, F; Cai, X; Hagmann, S; Kozhuharov, C; Liesen, D; Nolden, F; Ma, X; Mokler, P H; Orsić-Muthig, A; Steck, M; Sierpowski, D; Tashenov, S; Warczak, A; Zou, Y

    2004-05-21

    Radiative recombination transitions into the ground state of cooled bare and hydrogenlike uranium ions were measured at the storage ring ESR. By comparing the corresponding x-ray centroid energies, this technique allows for a direct measurement of the electron-electron contribution to the ionization potential in the heaviest He-like ions. For the two-electron contribution to the ionization potential of He-like uranium we obtain a value of 2248+/-9 eV. This represents the most accurate determination of two-electron effects in the domain of high-Z He-like ions, and the accuracy reaches already the size of the specific two-electron radiative QED corrections.

  6. Two-electron photo-oxidation of betanin on titanium dioxide and potential for improved dye-sensitized solar energy conversion

    OpenAIRE

    Banerji, N.; Hayes, S. C.; Knorr, Fritz J.; Melamen, Deborah J.; Mchale, Jeanne L.; Marchioro, Arianna; Moser, Jacques-Edouard

    2014-01-01

    The plant pigment betanin is investigated as a dye-sensitizer on TiO2 with regard to its potential to undergo two- electron oxidation following one-photon excitation. Electrochemical, spectroelectrochemical and transient absorption measurements provide evidence for two-electron proton-coupled photo-oxidation leading to a quinone methide interme- diate which rearranges to 2-decarboxy-2,3-dehydrobetanin. Time-resolved spectroscopy measurements of betanin on nanocrystalline TiO2 and ZrO2 films w...

  7. Two-electron photo-oxidation of betanin on titanium dioxide and potential for improved dye-sensitized solar energy conversion

    OpenAIRE

    Knorr, Fritz J.; Malamen, Deborah J.; Mchale, Jeanne L.; Marchioro, Arianna; Moser, Jacques-Edouard

    2014-01-01

    The plant pigment betanin is investigated as a dye-sensitizer on TiO2 with regard to its potential to undergo two-electron oxidation following one-photon excitation. Electrochemical, spectroelectrochemical and transient absorption measurements provide evidence for two-electron proton-coupled photo-oxidation leading to a quinone methide intermediate which rearranges to 2-decarboxy-2,3-dehydrobetanin. Time-resolved spectroscopy measurements of betanin on nanocrystalline TiO2 and ZrO2 films were...

  8. Hybrid microelectronic technology

    Science.gov (United States)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  9. Hybrid Gear

    Science.gov (United States)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  10. Hybrid Qualifications

    DEFF Research Database (Denmark)

    has turned out as a major focus of European education and training policies and certainly is a crucial principle underlying the European Qualifications Framework (EQF). In this context, «hybrid qualifications» (HQ) may be seen as an interesting approach to tackle these challenges as they serve «two...... masters», i.e. by producing skills for the labour market and enabling individuals to progress more or less directly to higher education. The specific focus of this book is placed on conditions, structures and processes which help to combine VET with qualifications leading into higher education...

  11. Theoretical analysis of the two-electron transfer reaction and experimental studies with surface-confined cytochrome c peroxidase using large-amplitude Fourier transformed AC voltammetry.

    Science.gov (United States)

    Stevenson, Gareth P; Lee, Chong-Yong; Kennedy, Gareth F; Parkin, Alison; Baker, Ruth E; Gillow, Kathryn; Armstrong, Fraser A; Gavaghan, David J; Bond, Alan M

    2012-06-26

    A detailed analysis of the cooperative two-electron transfer of surface-confined cytochrome c peroxidase (CcP) in contact with pH 6.0 phosphate buffer solution has been undertaken. This investigation is prompted by the prospect of achieving a richer understanding of this biologically important system via the employment of kinetically sensitive, but background devoid, higher harmonic components available in the large-amplitude Fourier transform ac voltammetric method. Data obtained from the conventional dc cyclic voltammetric method are also provided for comparison. Theoretical considerations based on both ac and dc approaches are presented for cases where reversible or quasi-reversible cooperative two-electron transfer involves variation in the separation of their reversible potentials, including potential inversion (as described previously for solution phase studies), and reversibility of the electrode processes. Comparison is also made with respect to the case of a simultaneous two-electron transfer process that is unlikely to occur in the physiological situation. Theoretical analysis confirms that the ac higher harmonic components provide greater sensitivity to the various mechanistic nuances that can arise in two-electron surface-confined processes. Experimentally, the ac perturbation with amplitude and frequency of 200 mV and 3.88 Hz, respectively, was employed to detect the electron transfer when CcP is confined to the surface of a graphite electrode. Simulations based on cooperative two-electron transfer with the employment of reversible potentials of 0.745 ± 0.010 V, heterogeneous electron transfer rate constants of between 3 and 10 s(-1) and charge transfer coefficients of 0.5 for both processes fitted experimental data for the fifth to eighth ac harmonics. Imperfections in theory-experiment comparison are consistent with kinetic and thermodynamic dispersion and other nonidealities not included in the theory used to model the voltammetry of surface

  12. Intuitionistic hybrid logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area.......Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area....

  13. Continuity Controlled Hybrid Automata

    OpenAIRE

    Bergstra, J. A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of hybrid automata as timed transition systems. We also relate the synchronized product operator on hybrid automata to the parallel composition operator of the process algebra. It turns out that the f...

  14. Hybridized tetraquarks

    Directory of Open Access Journals (Sweden)

    A. Esposito

    2016-07-01

    Full Text Available We propose a new interpretation of the neutral and charged X,Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules but rather a manifestation of the interplay between the two. While meson molecules need a negative or zero binding energy, its counterpart for h-tetraquarks is required to be positive. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs0π± channel by the D0 Collaboration and the negative result presented subsequently by the LHCb Collaboration are understood in this scheme, together with a considerable portion of available data on X,Z particles. Considerations on a state with the same quantum numbers as the X(5568 are also made.

  15. Hybridized Tetraquarks

    CERN Document Server

    Esposito, A.; Polosa, A.D.

    2016-01-01

    We propose a new interpretation of the neutral and charged X, Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules. The latter would require a negative or zero binding energy whose counterpart in h-tetraquarks is a positive quantity. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs pi+- channel by the D0 collaboration and the negative result presented subsequently by the LHCb collaboration are understood in this scheme, together with a considerable portion of available data on X, Z particles. Considerations on a state with the same quantum numbers as the X(5568) are also made.

  16. Explicit energy density functional for the Crandall two-electron model atom with harmonic confinement and inverse square law inter-particle repulsion

    Energy Technology Data Exchange (ETDEWEB)

    Amovilli, C., E-mail: amovilli@dcci.unipi.it [Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa (Italy); March, N.H. [Department of Physics, University of Antwerp, Antwerp (Belgium); University of Oxford, Oxford (United Kingdom)

    2014-05-01

    Though density functional theory is already developed in useful practical numerical forms, no explicit simple ground-state energy density functional exists. Here, towards establishing such a theory, we present the ground-state energy of the Crandall et al.'s two-electron spin-compensated model atom in terms of ∇{sup 2}ρ(r)/ρ(r) evaluated at r=0, where ρ(r) is the electron density.

  17. Explicit energy density functional for the Crandall two-electron model atom with harmonic confinement and inverse square law inter-particle repulsion

    Science.gov (United States)

    Amovilli, C.; March, N. H.

    2014-05-01

    Though density functional theory is already developed in useful practical numerical forms, no explicit simple ground-state energy density functional exists. Here, towards establishing such a theory, we present the ground-state energy of the Crandall et al.'s two-electron spin-compensated model atom in terms of ∇2ρ(r)/ρ(r) evaluated at r=0, where ρ(r) is the electron density.

  18. First-order density matrix as a functional of the ground-state electron density for harmonic confinement of two electrons which also interact harmonically

    Energy Technology Data Exchange (ETDEWEB)

    March, N.H

    2002-12-30

    The first-order density matrix {gamma}(r{sub 1},r{sub 2}) for the ground-state of a model two-electron atom is explicitly constructed from the electron density {rho}(r). The model has harmonic confinement plus interparticle harmonic interactions. {gamma}(r{sub 1},r{sub 2}) and {rho}(r) are related non-locally, even though no density gradients and no quadratures appear.

  19. Dual function photocatalysis of cyano-bridged heteronuclear metal complexes for water oxidation and two-electron reduction of dioxygen to produce hydrogen peroxide as a solar fuel.

    Science.gov (United States)

    Aratani, Yusuke; Suenobu, Tomoyoshi; Ohkubo, Kei; Yamada, Yusuke; Fukuzumi, Shunichi

    2017-03-25

    The photocatalytic production of hydrogen peroxide from water and dioxygen under visible light irradiation was made possible by using polymeric cyano-bridged heteronuclear metal complexes (M(II)[Ru(II)(CN)4(bpy)]; M(II) = Ni(II), Fe(II) and Mn(II)), where the photocatalytic two-electron reduction of O2 and water oxidation were catalysed by the Ru and M(II) moieties, respectively.

  20. The Three-Dimensional Structure of NAD(P)H:Quinone Reductase, a Flavoprotein Involved in Cancer Chemoprotection and Chemotherapy: Mechanism of the Two-Electron Reduction

    Science.gov (United States)

    Li, Rongbao; Bianchet, Mario A.; Talalay, Paul; Amzel, L. Mario

    1995-09-01

    Quinone reductase [NAD(P)H:(quinone acceptor) oxidoreductase, EC 1.6.99.2], also called DT diaphorase, is a homodimeric FAD-containing enzyme that catalyzes obligatory NAD(P)H-dependent two-electron reductions of quinones and protects cells against the toxic and neoplastic effects of free radicals and reactive oxygen species arising from one-electron reductions. These two-electron reductions participate in the reductive bioactivation of cancer chemotherapeutic agents such as mitomycin C in tumor cells. Thus, surprisingly, the same enzymatic reaction that protects normal cells activates cytotoxic drugs used in cancer chemotherapy. The 2.1-Å crystal structure of rat liver quinone reductase reveals that the folding of a portion of each monomer is similar to that of flavodoxin, a bacterial FMN-containing protein. Two additional portions of the polypeptide chains are involved in dimerization and in formation of the two identical catalytic sites to which both monomers contribute. The crystallographic structures of two FAD-containing enzyme complexes (one containing NADP^+, the other containing duroquinone) suggest that direct hydride transfers from NAD(P)H to FAD and from FADH_2 to the quinone [which occupies the site vacated by NAD(P)H] provide a simple rationale for the obligatory two-electron reductions involving a ping-pong mechanism.

  1. Continuity Controlled Hybrid Automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  2. Continuity controlled Hybrid Automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2008-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  3. Electron-transfer and acid-base properties of a two-electron oxidized form of quaterpyrrole that acts as both an electron donor and an acceptor.

    Science.gov (United States)

    Zhang, Min; E, Wenbo; Ohkubo, Kei; Sanchez-Garcia, David; Yoon, Dae-Wi; Sessler, Jonathan L; Fukuzumi, Shunichi; Kadish, Karl M

    2008-02-21

    Electron-transfer interconversion between the four-electron oxidized form of a quaterpyrrole (abbreviated as P4 for four pyrroles) and the two-electron oxidized form (P4H2) as well as between P4H2 and its fully reduced form (P4H4) bearing analogous substituents in the alpha- and beta-pyrrolic positions was studied by means of cyclic voltammetry and UV-visible spectroelectrochemistry combined with ESR and laser flash photolysis measurements. The two-electron oxidized form, P4H2, acts as both an electron donor and an electron acceptor. The radical cation (P4H2*+) and radical anion (P4H2*-) are both produced by photoinduced electron transfer from dimeric 1-benzyl-1,4-dihydronicotinamide to P4H2, whereas the cation radical form of the compound is also produced by electron-transfer oxidation of P4H2 with [Ru(bpy)3]3+. The ESR spectra of P4H2*+ and P4H2*- were recorded at low temperature and exhibit spin delocalization over all four pyrrole units. Thus, the two-electron oxidized form of the quaterpyrrole (P4H2) displays redox and electronic features analogous to those seen in the case of porphyrins and may be considered as a simple, open-chain model of this well-studied tetrapyrrolic macrocycle. The dynamics of deprotonation from P4H2*+ and disproportionation of P4H2 were examined by laser flash photolysis measurements of photoinduced electron-transfer oxidation and reduction of P4H2, respectively.

  4. Negative-energy states in the Dirac-Hartree-Fock problem - The effect of omission of two-electron integrals involving the small component

    Science.gov (United States)

    Dyall, Kenneth G.

    1992-01-01

    The effect of omission of two-electron integrals involving basis functions for the small component of the wavefunction on the eigenvalue spectrum in the Dirac-Hartree-Fock problem is studied. From an analysis of the Fock matrix it is shown that omission of these integrals moves the negative-energy states down, not up. Their complete omission does not give rise to intruder states. The appearance of intruder states occurs when only some of the core integrals are omitted, due to the nature of particular contraction schemes used for the core basis functions. Use of radially localized functions rather than atomic functions alleviates the intruder state problem.

  5. From hybrid swarms to swarms of hybrids

    Science.gov (United States)

    The introgression of modern humans (Homo sapiens) with Neanderthals 40,000 YBP after a half-million years of separation, may have led to the best example of a hybrid swarm on earth. Modern trade and transportation in support of the human hybrids has continued to introduce additional species, genotyp...

  6. The Hybrid Museum: Hybrid Economies of Meaning

    DEFF Research Database (Denmark)

    Vestergaard, Vitus

    2013-01-01

    this article shows that there are two different museum mindsets where the second mindset leans towards participatory practices. It is shown how a museum can support a hybrid economy of meaning that builds on both a user generated economy of meaning and an institutional economy of meaning and adds value to both....... Such a museum is referred to as a hybrid museum....

  7. Hydraulic Hybrid Vehicles

    Science.gov (United States)

    EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

  8. Hybrid Management in Hospitals

    DEFF Research Database (Denmark)

    Byrkjeflot, Haldor; Jespersen, Peter Kragh

    2010-01-01

    Artiklen indeholder et litteraturbaseret studium af ledelsesformer i sygehuse, hvor sundhedsfaglig ledelse og generel ledelse mikses til hybride ledelsesformer......Artiklen indeholder et litteraturbaseret studium af ledelsesformer i sygehuse, hvor sundhedsfaglig ledelse og generel ledelse mikses til hybride ledelsesformer...

  9. Resin Catalyst Hybrids

    Institute of Scientific and Technical Information of China (English)

    S. Asaoka

    2005-01-01

    @@ 1Introduction: What are resin catalyst hybrids? There are typically two types of resin catalyst. One is acidic resin which representative is polystyrene sulfonic acid. The other is basic resin which is availed as metal complex support. The objective items of this study on resin catalyst are consisting of pellet hybrid, equilibrium hybrid and function hybrid of acid and base,as shown in Fig. 1[1-5].

  10. Mesoscale hybrid calibration artifact

    Science.gov (United States)

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  11. Realizing the Hybrid Library.

    Science.gov (United States)

    Pinfield, Stephen; Eaton, Jonathan; Edwards, Catherine; Russell, Rosemary; Wissenburg, Astrid; Wynne, Peter

    1998-01-01

    Outlines five projects currently funded by the United Kingdom's Electronic Libraries Program (eLib): HyLiFe (Hybrid Library of the Future), MALIBU (MAnaging the hybrid Library for the Benefit of Users), HeadLine (Hybrid Electronic Access and Delivery in the Library Networked Environment), ATHENS (authentication scheme), and BUILDER (Birmingham…

  12. Homoploid hybrid expectations

    Science.gov (United States)

    Homoploid hybrid speciation occurs when a stable, fertile, and reproductively isolated lineage results from hybridization between two distinct species without a change in ploidy level. Reproductive isolation between a homoploid hybrid species and its parents is generally attained via chromosomal re...

  13. Hybrid armature projectile

    Science.gov (United States)

    Hawke, Ronald S.; Asay, James R.; Hall, Clint A.; Konrad, Carl H.; Sauve, Gerald L.; Shahinpoor, Mohsen; Susoeff, Allan R.

    1993-01-01

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasama blowby.

  14. Intraply Hybrid Composite Design

    Science.gov (United States)

    Chamis, C. C.; Sinclair, J. H.

    1986-01-01

    Several theoretical approaches combined in program. Intraply hybrid composites investigated theoretically and experimentally at Lewis Research Center. Theories developed during investigations and corroborated by attendant experiments used to develop computer program identified as INHYD (Intraply Hybrid Composite Design). INHYD includes several composites micromechanics theories, intraply hybrid composite theories, and integrated hygrothermomechanical theory. Equations from theories used by program as appropriate for user's specific applications.

  15. Hybrid quantum information processing

    Energy Technology Data Exchange (ETDEWEB)

    Furusawa, Akira [Department of Applied Physics, School of Engineering, The University of Tokyo (Japan)

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  16. The hydrogen hybrid option

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.R.

    1993-10-15

    The energy efficiency of various piston engine options for series hybrid automobiles are compared with conventional, battery powered electric, and proton exchange membrane (PEM) fuel cell hybrid automobiles. Gasoline, compressed natural gas (CNG), and hydrogen are considered for these hybrids. The engine and fuel comparisons are done on a basis of equal vehicle weight, drag, and rolling resistance. The relative emissions of these various fueled vehicle options are also presented. It is concluded that a highly optimized, hydrogen fueled, piston engine, series electric hybrid automobile will have efficiency comparable to a similar fuel cell hybrid automobile and will have fewer total emissions than the battery powered vehicle, even without a catalyst.

  17. Hybridization and extinction.

    Science.gov (United States)

    Todesco, Marco; Pascual, Mariana A; Owens, Gregory L; Ostevik, Katherine L; Moyers, Brook T; Hübner, Sariel; Heredia, Sylvia M; Hahn, Min A; Caseys, Celine; Bock, Dan G; Rieseberg, Loren H

    2016-08-01

    Hybridization may drive rare taxa to extinction through genetic swamping, where the rare form is replaced by hybrids, or by demographic swamping, where population growth rates are reduced due to the wasteful production of maladaptive hybrids. Conversely, hybridization may rescue the viability of small, inbred populations. Understanding the factors that contribute to destructive versus constructive outcomes of hybridization is key to managing conservation concerns. Here, we survey the literature for studies of hybridization and extinction to identify the ecological, evolutionary, and genetic factors that critically affect extinction risk through hybridization. We find that while extinction risk is highly situation dependent, genetic swamping is much more frequent than demographic swamping. In addition, human involvement is associated with increased risk and high reproductive isolation with reduced risk. Although climate change is predicted to increase the risk of hybridization-induced extinction, we find little empirical support for this prediction. Similarly, theoretical and experimental studies imply that genetic rescue through hybridization may be equally or more probable than demographic swamping, but our literature survey failed to support this claim. We conclude that halting the introduction of hybridization-prone exotics and restoring mature and diverse habitats that are resistant to hybrid establishment should be management priorities.

  18. Spoof Plasmon Hybridization

    CERN Document Server

    Zhang, Jingjing; Luo, Yu; Shen, Xiaopeng; Maier, Stefan A; Cui, Tie Jun

    2016-01-01

    Plasmon hybridization between closely spaced nanoparticles yields new hybrid modes not found in individual constituents, allowing for the engineering of resonance properties and field enhancement capabilities of metallic nanostructure. Experimental verifications of plasmon hybridization have been thus far mostly limited to optical frequencies, as metals cannot support surface plasmons at longer wavelengths. Here, we introduce the concept of 'spoof plasmon hybridization' in highly conductive metal structures and investigate experimentally the interaction of localized surface plasmon resonances (LSPR) in adjacent metal disks corrugated with subwavelength spiral patterns. We show that the hybridization results in the splitting of spoof plasmon modes into bonding and antibonding resonances analogous to molecular orbital rule and plasmonic hybridization in optical spectrum. These hybrid modes can be manipulated to produce enormous field enhancements (larger than 5000) by tuning the separation between disks or alte...

  19. Enhanced Constraints for Accurate Lower Bounds on Many-Electron Quantum Energies from Variational Two-Electron Reduced Density Matrix Theory.

    Science.gov (United States)

    Mazziotti, David A

    2016-10-07

    A central challenge of physics is the computation of strongly correlated quantum systems. The past ten years have witnessed the development and application of the variational calculation of the two-electron reduced density matrix (2-RDM) without the wave function. In this Letter we present an orders-of-magnitude improvement in the accuracy of 2-RDM calculations without an increase in their computational cost. The advance is based on a low-rank, dual formulation of an important constraint on the 2-RDM, the T2 condition. Calculations are presented for metallic chains and a cadmium-selenide dimer. The low-scaling T2 condition will have significant applications in atomic and molecular, condensed-matter, and nuclear physics.

  20. Enhanced Constraints for Accurate Lower Bounds on Many-Electron Quantum Energies from Variational Two-Electron Reduced Density Matrix Theory

    Science.gov (United States)

    Mazziotti, David A.

    2016-10-01

    A central challenge of physics is the computation of strongly correlated quantum systems. The past ten years have witnessed the development and application of the variational calculation of the two-electron reduced density matrix (2-RDM) without the wave function. In this Letter we present an orders-of-magnitude improvement in the accuracy of 2-RDM calculations without an increase in their computational cost. The advance is based on a low-rank, dual formulation of an important constraint on the 2-RDM, the T 2 condition. Calculations are presented for metallic chains and a cadmium-selenide dimer. The low-scaling T 2 condition will have significant applications in atomic and molecular, condensed-matter, and nuclear physics.

  1. Performance Limits of Photoelectrochemical CO2 Reduction Based on Known Electrocatalysts and the Case for Two-Electron Reduction Products

    DEFF Research Database (Denmark)

    Vesborg, Peter Christian Kjærgaard; Seger, Brian

    2016-01-01

    Solar-drivenreduction of CO2 to solar fuels as an alternative to H2 via water splitting is an intriguing proposition. We modelthe solar-to-fuel (STF) efficiencies using realistic parameters basedon recently reported CO2 reduction catalysts with a highperformance tandem photoabsorber structure. CO...... and formate, whichare both two-electron reduction products, offer STF efficiencies (20.0%and 18.8%) competitively close to that of solar H2 (21.8%)despite markedly worse reduction catalysis. The slightly lower efficiencytoward carbon products is mainly due to electrolyte resistance, notoverpotential. Using...... a cell design where electrolyte resistance isminimized makes formate the preferred product from an efficiency standpoint(reaching 22.7% STF efficiency). On the other hand, going beyond a2 electron reduction reaction, the more highly reduced products seemunviable with presently available electrocatalysts...

  2. Time-dependent renormalized natural orbital theory applied to the two-electron spin-singlet case: ground state, linear response, and autoionization

    CERN Document Server

    Brics, M

    2013-01-01

    Favorably scaling numerical time-dependent many-electron techniques such as time-dependent density functional theory (TDDFT) with adiabatic exchange-correlation potentials typically fail in capturing highly correlated electron dynamics. We propose a method based on natural orbitals, i.e., the eigenfunctions of the one-body reduced density matrix, that is almost as inexpensive numerically as adiabatic TDDFT, but which is capable of describing correlated phenomena such as doubly excited states, autoionization, Fano profiles in the photoelectron spectra, and strong-field ionization in general. Equations of motion (EOM) for natural orbitals and their occupation numbers have been derived earlier. We show that by using renormalized natural orbitals (RNO) both can be combined into one equation governed by a hermitian effective Hamiltonian. We specialize on the two-electron spin-singlet system, known as being a "worst case" testing ground for TDDFT, and employ the widely used, numerically exactly solvable, one-dimens...

  3. Zn-catalyzed enantio- and diastereoselective formal [4 + 2] cycloaddition involving two electron-deficient partners: asymmetric synthesis of piperidines from 1-azadienes and nitro-alkenes.

    Science.gov (United States)

    Chu, John C K; Dalton, Derek M; Rovis, Tomislav

    2015-04-08

    We report a catalytic asymmetric synthesis of piperidines through [4 + 2] cycloaddition of 1-azadienes and nitro-alkenes. The reaction uses earth abundant Zn as catalyst and is highly diastereo- and regioselective. A novel BOPA ligand (F-BOPA) confers high reactivity and enantioselectivity in the process. The presence of ortho substitution on the arenes adjacent to the bis(oxazolines) was found to be particularly impactful, due to limiting the undesired coordination of 1-azadiene to the Lewis acid and thus allowing the reaction to be carried out at lower temperature. A series of secondary kinetic isotope effect studies using a range of ligands implicates a stepwise mechanism for the transformation, involving an initial Michael-type addition of the imine to the nitro-alkene followed by a cyclization event. The stepwise mechanism obviates the electronic requirement inherent to a concerted mechanism, explaining the successful cycloaddition between two electron-deficient partners.

  4. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is

  5. Henkin and Hybrid Logic

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Huertas, Antonia; Manzano, Maria;

    2014-01-01

    Leon Henkin was not a modal logician, but there is a branch of modal logic that has been deeply influenced by his work. That branch is hybrid logic, a family of logics that extend orthodox modal logic with special proposition symbols (called nominals) that name worlds. This paper explains why...... Henkin’s techniques are so important in hybrid logic. We do so by proving a completeness result for a hybrid type theory called HTT, probably the strongest hybrid logic that has yet been explored. Our completeness result builds on earlier work with a system called BHTT, or basic hybrid type theory...... is due to the first-order perspective, which lies at the heart of Henin’s best known work and hybrid logic....

  6. BSA Hybrid Synthesized Polymer

    Institute of Scientific and Technical Information of China (English)

    Zong Bin LIU; Xiao Pei DENG; Chang Sheng ZHAO

    2006-01-01

    Bovine serum albumin (BSA), a naturally occurring biopolymer, was regarded as a polymeric material to graft to an acrylic acid (AA)-N-vinyl pyrrolidone (NVP) copolymer to form a biomacromolecular hybrid polymer. The hybrid polymer can be blended with polyethersulfone (PES) to increase the hydrophilicity of the PES membrane, which suggested that the hybrid polymer might have a wide application in the modification of biomaterials.

  7. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    a differential action, which allows differential equations as primitive actions. The extension allows us to model hybrid systems with both continuous and discrete behaviour. The main result of this paper is an extension of such a hybrid action system with parallel composition. The extension does not change...... the original meaning of the parallel composition, and therefore also the ordinary action systems can be composed in parallel with the hybrid action systems....

  8. HYBRID VEHICLE CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    V. Dvadnenko

    2016-06-01

    Full Text Available The hybrid vehicle control system includes a start–stop system for an internal combustion engine. The system works in a hybrid mode and normal vehicle operation. To simplify the start–stop system, there were user new possibilities of a hybrid car, which appeared after the conversion. Results of the circuit design of the proposed system of basic blocks are analyzed.

  9. Nanoscale Organic Hybrid Electrolytes

    KAUST Repository

    Nugent, Jennifer L.

    2010-08-20

    Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Hybrid radiator cooling system

    Science.gov (United States)

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  11. Hybrid Unifying Variable Supernetwork Model

    Institute of Scientific and Technical Information of China (English)

    LIU; Qiang; FANG; Jin-qing; LI; Yong

    2015-01-01

    In order to compare new phenomenon of topology change,evolution,hybrid ratio and network characteristics of unified hybrid network theoretical model with unified hybrid supernetwork model,this paper constructed unified hybrid variable supernetwork model(HUVSM).The first layer introduces a hybrid ratio dr,the

  12. Large Unifying Hybrid Supernetwork Model

    Institute of Scientific and Technical Information of China (English)

    LIU; Qiang; FANG; Jin-qing; LI; Yong

    2015-01-01

    For depicting multi-hybrid process,large unifying hybrid network model(so called LUHNM)has two sub-hybrid ratios except dr.They are deterministic hybrid ratio(so called fd)and random hybrid ratio(so called gr),respectively.

  13. Hybrid Rocket Technology

    National Research Council Canada - National Science Library

    Sankaran Venugopal; K K Rajesh; V Ramanujachari

    2011-01-01

    With their unique operational characteristics, hybrid rockets can potentially provide safer, lower-cost avenues for spacecraft and missiles than the current solid propellant and liquid propellant systems...

  14. Hybrid FOSS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Armstrong researchers are continuing their efforts to further develop FOSS technologies. A hybrid FOSS technique (HyFOSS) employs conventional continuous grating...

  15. From hybrid swarms to swarms of hybrids

    Science.gov (United States)

    Stohlgren, Thomas J.; Szalanski, Allen L; Gaskin, John F.; Young, Nicholas E.; West, Amanda; Jarnevich, Catherine S.; Tripodi, Amber

    2015-01-01

    Science has shown that the introgression or hybridization of modern humans (Homo sapiens) with Neanderthals up to 40,000 YBP may have led to the swarm of modern humans on earth. However, there is little doubt that modern trade and transportation in support of the humans has continued to introduce additional species, genotypes, and hybrids to every country on the globe. We assessed the utility of species distributions modeling of genotypes to assess the risk of current and future invaders. We evaluated 93 locations of the genus Tamarix for which genetic data were available. Maxent models of habitat suitability showed that the hybrid, T. ramosissima x T. chinensis, was slightly greater than the parent taxa (AUCs > 0.83). General linear models of Africanized honey bees, a hybrid cross of Tanzanian Apis mellifera scutellata and a variety of European honey bee including A. m. ligustica, showed that the Africanized bees (AUC = 0.81) may be displacing European honey bees (AUC > 0.76) over large areas of the southwestern U.S. More important, Maxent modeling of sub-populations (A1 and A26 mitotypes based on mDNA) could be accurately modeled (AUC > 0.9), and they responded differently to environmental drivers. This suggests that rapid evolutionary change may be underway in the Africanized bees, allowing the bees to spread into new areas and extending their total range. Protecting native species and ecosystems may benefit from risk maps of harmful invasive species, hybrids, and genotypes.

  16. How is the water molecule activated on metalloporphyrins? Oxygenation of substrates induced through one-photon/two-electron conversion in artificial photosynthesis by visible light.

    Science.gov (United States)

    Shimada, Tetsuya; Kumagai, Akihiro; Funyu, Shigeaki; Takagi, Shinsuke; Masui, Dai; Nabetani, Yu; Tachibana, Hiroshi; Tryk, Donald A; Inoue, Haruo

    2012-01-01

    The reaction mechanism of the highly efficient (phi = 0.60), selective photochemical epoxidation of alkenes sensitized by CO-coordinated tetra(2,4,6-trimethyl)phenylporphyrinatoruthenium(II) (Ru(II)TMP(CO)), with water acting both as an electron and oxygen atom donor, was investigated. The steady-state light irradiation of the reaction mixture indicated the formation of the Ru(II)TMP (CO) cation radical under neutral conditions, which was effectively trapped by an hydroxide ion to regenerate the starting sensitizer. By means of a laser flash photolysis experiment, the formation of the cation radical as the primary process from the triplet excited state of Ru(II)TMP(CO) was clearly observed. Four kinds of transients were detected in completely different ranges of the delay time: the excited triplet state of Ru(II)TMP(CO) [delay time region reaction mechanism was revealed that involves RuTMP(CO) cation radical formation from the triplet excited state of the sensitizer, followed by attack of an hydroxide ion to form an hydroxyl-coordinated Ru-porphyrin (Intermediate [I]) and subsequent reaction with cyclohexene to form Intermediate [II]. The kinetics for each step of the successive processes was carefully analyzed and their rate constants were determined. The two-electron oxidation of water by one-photon irradiation, as revealed in the photochemical epoxidation, is proposed to be one of the more promising candidates to get through the bottleneck of water oxidation in artificial photosynthesis.

  17. Influence of variations in the electron-electron interaction on the ground state metric space "band structure" of a two-electron magnetic system

    Science.gov (United States)

    Sharp, P. M.; D'Amico, I.

    2016-02-01

    We consider a model system of two electrons confined in a two-dimensional harmonic oscillator potential, with the electrons interacting via an α / r2 potential, and subject to a magnetic field applied perpendicular to the plane of confinement. Our results show that variations in the strength of the electron-electron interaction generate a "band structure" in ground state metric spaces, which shares many characteristics with those generated as a result of varying the confinement potential. In particular, the metric spaces for wavefunctions, particle densities, and paramagnetic current densities all exhibit distinct "bands" and "gaps". The behavior of the polar angle of the bands also shares traits with that obtained by varying the confinement potential, but the behavior of the arc lengths of the bands on the metric space spheres can be seen to be different for the two cases and opposite for a large range of angular momentum values. The findings here and in Refs. [1,2] demonstrate that the "band structure" that arises in ground state metric spaces when a magnetic field is applied is a robust feature.

  18. Ytterbocenes as one- and two-electron reductants in their reactions with diazadienes: YbIII mixed-ligand bent-sandwich complexes containing a dianion of diazabutadiene.

    Science.gov (United States)

    Trifonov, Alexander A; Borovkov, Ivan A; Fedorova, Elena A; Fukin, Georgii K; Larionova, Joulia; Druzhkov, Nikolai O; Cherkasov, Vladimir K

    2007-01-01

    Ytterbocene [Yb(C(5)MeH(4))(2)(thf)(2)] reacts with diazabutadiene 2,6-iPr(2)C(6)H(3)-N=CH-CH=N-C(6)H(3)iPr(2)-2,6 (DAD) as a one-electron reductant to afford a bis(cyclopentadienyl) Yb(III) derivative containing a DAD radical anion [Yb(C(5)MeH(4))(2)(dad(-.))]. However, ytterbocenes [YbCp*(2)(thf)(2)] (Cp*=C(5)Me(5), C(5)Me(4)H) coordinated by sterically demanding cyclopentadienyl ligands act as two-electron reductants in their reactions with DAD. These reactions occur by abstraction of one Cp* ring and result in the formation of novel Yb(III) mixed-ligand bent-sandwich complexes, [YbCp*(dad)(thf)], in which the dianion of DAD has an uncommon terminal eta(4)-coordination to the ytterbium atom. The variable-temperature magnetic measurements of complex [Yb(C(5)Me(5))(dad)(thf)] suggest the existence of redox tautomerism for this compound.

  19. Investigations of the Lamb shift in heavy one and two electron systems; Untersuchungen zur Lamb-Verschiebung in schweren Ein- und Zwei-Elektronen-Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Reuschl, Regina

    2008-07-01

    Experiments on the 1s Lamb-shift in heavy H-like ions and on the intra-shell transitions in heavy He-like systems have been performed. These investigations are of particular interest to verify the validity of quantum electrodynamics (QED) in extremely strong Coulomb fields. In addition, in heavy systems not only QED but also relativistic effects start to play a key role. The experiments have been performed at the gas-jet target of the experimental storage ring (ESR) at GSI. In an experiment with He-like uranium we were able to directly measure the intra-shell transition 2{sup 3}P{sub 2}{yields}2{sup 3}S{sub 1}, in a high-Z system for the very first time. This has been achieved by combining the results from a high-resolution Bragg crystal-spectrometer and a standard planar Germanium detector. A fit of the experimental spectrum with data obtained from a simulation shows, the theoretical predictions describe the transition dynamics very well in this two-electron system. Another experiment has been performed on H-like lead to investigate the 1s Lamb-shift in heavy H-like systems. Here, a high-resolution Laue crystal-spectrometer has been commissioned together with novel high-resolution two dimensional micro-strip Ge-detectors. The combination of both instruments is a very promising tool for future high-precision X-ray experiments. (orig.)

  20. Optimization of levulinic acid from lignocellulosic biomass using a new hybrid catalyst.

    Science.gov (United States)

    Ya'aini, Nazlina; Amin, Nor Aishah Saidina; Asmadi, Mohd

    2012-07-01

    Conversion of glucose, empty fruit bunch (efb) and kenaf to levulinic acid over a new hybrid catalyst has been investigated in this study. The characterization and catalytic performance results revealed that the physico-chemical properties of the new hybrid catalyst comprised of chromium chloride and HY zeolite increased the levulinic acid production from glucose compared to the parent catalysts. Optimization of the glucose conversion process using two level full factorial designs (2(3)) with two center points reported 55.2% of levulinic acid yield at 145.2 °C, 146.7 min and 12.0% of reaction temperature, reaction time and catalyst loading, respectively. Subsequently, the potential of efb and kenaf for producing levulinic acid at the optimum conditions was established after 53.2% and 66.1% of efficiencies were reported. The observation suggests that the hybrid catalyst has a potential to be used in biomass conversion to levulinic acid.

  1. Cardiac hybrid imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

    2014-05-15

    Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)

  2. Hybrid intelligent engineering systems

    CERN Document Server

    Jain, L C; Adelaide, Australia University of

    1997-01-01

    This book on hybrid intelligent engineering systems is unique, in the sense that it presents the integration of expert systems, neural networks, fuzzy systems, genetic algorithms, and chaos engineering. It shows that these new techniques enhance the capabilities of one another. A number of hybrid systems for solving engineering problems are presented.

  3. A Hybrid Imagination

    DEFF Research Database (Denmark)

    Jamison, Andrew; Christensen, Steen Hyldgaard; Botin, Lars

    contexts, or sites, for mixing scientific knowledge and technical skills from different fields and social domains into new combinations, thus fostering what the authors term a “hybrid imagination”. Such a hybrid imagination is especially important today, as a way to counter the competitive and commercial...

  4. Hybrid trajectory spaces

    NARCIS (Netherlands)

    Collins, P.J.

    2005-01-01

    In this paper, we present a general framework for describing and studying hybrid systems. We represent the trajectories of the system as functions on a hybrid time domain, and the system itself by its trajectory space, which is the set of all possible trajectories. The trajectory space is given a na

  5. Editorial: Hybrid Systems

    DEFF Research Database (Denmark)

    Olderog, Ernst-Rüdiger; Ravn, Anders Peter

    2007-01-01

    An introduction to three papers in a special issue on Hybrid Systems. These paper were first presented at an IFIP WG 2.2 meeting in Skagen 2005.......An introduction to three papers in a special issue on Hybrid Systems. These paper were first presented at an IFIP WG 2.2 meeting in Skagen 2005....

  6. Hybrid reactors. [Fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  7. Hybrid propulsion technology program

    Science.gov (United States)

    1990-01-01

    Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

  8. Universal transport signatures in two-electron molecular quantum dots: gate-tunable Hund's rule, underscreened Kondo effect and quantum phase transitions.

    Science.gov (United States)

    Florens, Serge; Freyn, Axel; Roch, Nicolas; Wernsdorfer, Wolfgang; Balestro, Franck; Roura-Bas, Pablo; Aligia, A A

    2011-06-22

    We review here some universal aspects of the physics of two-electron molecular transistors in the absence of strong spin-orbit effects. Several recent quantum dot experiments have shown that an electrostatic backgate could be used to control the energy dispersion of magnetic levels. We discuss how the generally asymmetric coupling of the metallic contacts to two different molecular orbitals can indeed lead to a gate-tunable Hund's rule in the presence of singlet and triplet states in the quantum dot. For gate voltages such that the singlet constitutes the (non-magnetic) ground state, one generally observes a suppression of low voltage transport, which can yet be restored in the form of enhanced cotunneling features at finite bias. More interestingly, when the gate voltage is controlled to obtain the triplet configuration, spin S = 1 Kondo anomalies appear at zero bias, with non-Fermi liquid features related to the underscreening of a spin larger than 1/2. Finally, the small bare singlet-triplet splitting in our device allows fine-tuning with the gate between these two magnetic configurations, leading to an unscreening quantum phase transition. This transition occurs between the non-magnetic singlet phase, where a two-stage Kondo effect occurs, and the triplet phase, where the partially compensated (underscreened) moment is akin to a magnetically 'ordered' state. These observations are put theoretically into a consistent global picture by using new numerical renormalization group simulations, tailored to capture sharp finite-voltage cotunneling features within the Coulomb diamonds, together with complementary out-of-equilibrium diagrammatic calculations on the two-orbital Anderson model. This work should shed further light on the complicated puzzle still raised by multi-orbital extensions of the classic Kondo problem.

  9. Two-electron reduced density matrices from the anti-Hermitian contracted Schrodinger equation: enhanced energies and properties with larger basis sets.

    Science.gov (United States)

    Mazziotti, David A

    2007-05-14

    Two-electron reduced density matrices (2-RDMs) have recently been directly determined from the solution of the anti-Hermitian contracted Schrodinger equation (ACSE) to obtain 95%-100% of the ground-state correlation energy of atoms and molecules, which significantly improves upon the accuracy of the contracted Schrodinger equation (CSE) [D. A. Mazziotti, Phys. Rev. Lett. 97, 143002 (2006)]. Two subsets of the CSE, the ACSE and the contraction of the CSE onto the one-particle space, known as the 1,3-CSE, have two important properties: (i) dependence upon only the 3-RDM and (ii) inclusion of all second-order terms when the 3-RDM is reconstructed as only a first-order functional of the 2-RDM. The error in the 1,3-CSE has an important role as a stopping criterion in solving the ACSE for the 2-RDM. Using a computationally more efficient implementation of the ACSE, the author treats a variety of molecules, including H2O, NH3, HCN, and HO3-, in larger basis sets such as correlation-consistent polarized double- and triple-zeta. The ground-state energy of neon is also calculated in a polarized quadruple-zeta basis set with extrapolation to the complete basis-set limit, and the equilibrium bond length and harmonic frequency of N2 are computed with comparison to experimental values. The author observes that increasing the basis set enhances the ability of the ACSE to capture correlation effects in ground-state energies and properties. In the triple-zeta basis set, for example, the ACSE yields energies and properties that are closer in accuracy to coupled cluster with single, double, and triple excitations than to coupled cluster with single and double excitations. In all basis sets, the computed 2-RDMs very closely satisfy known N-representability conditions.

  10. Hybrid electric vehicles TOPTEC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-06-21

    This one-day TOPTEC session began with an overview of hybrid electric vehicle technology. Updates were given on alternative types of energy storage, APU control for low emissions, simulation programs, and industry and government activities. The keynote speech was about battery technology, a key element to the success of hybrids. The TOPEC concluded with a panel discussion on the mission of hybrid electric vehicles, with a perspective from industry and government experts from United States and Canada on their view of the role of this technology.

  11. Hybrid systems with constraints

    CERN Document Server

    Daafouz, Jamal; Sigalotti, Mario

    2013-01-01

    Control theory is the main subject of this title, in particular analysis and control design for hybrid dynamic systems.The notion of hybrid systems offers a strong theoretical and unified framework to cope with the modeling, analysis and control design of systems where both continuous and discrete dynamics interact. The theory of hybrid systems has been the subject of intensive research over the last decade and a large number of diverse and challenging problems have been investigated. Nevertheless, many important mathematical problems remain open.This book is dedicated mainly to

  12. Hybrid Bloch Brane

    CERN Document Server

    Bazeia, D; Losano, L

    2016-01-01

    This work reports on models described by two real scalar fields coupled with gravity in the five-dimensional spacetime, with a warped geometry involving one infinite extra dimension. Through a mechanism that smoothly changes a thick brane into a hybrid brane, one investigates the appearance of hybrid branes hosting internal structure, characterized by the splitting on the energy density and the volcano potential, induced by the parameter which controls interactions between the two scalar fields. In particular, we investigate distinct symmetric and asymmetric hybrid brane scenarios.

  13. Hybrid Bloch brane

    Energy Technology Data Exchange (ETDEWEB)

    Bazeia, D.; Lima, Elisama E.M.; Losano, L. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, PB (Brazil)

    2017-02-15

    This work reports on models described by two real scalar fields coupled with gravity in the five-dimensional spacetime, with a warped geometry involving one infinite extra dimension. Through a mechanism that smoothly changes a thick brane into a hybrid brane, one investigates the appearance of hybrid branes hosting internal structure, characterized by the splitting on the energy density and the volcano potential, induced by the parameter which controls interactions between the two scalar fields. In particular, we investigate distinct symmetric and asymmetric hybrid brane scenarios. (orig.)

  14. Hybrid silicon evanescent devices

    Directory of Open Access Journals (Sweden)

    Alexander W. Fang

    2007-07-01

    Full Text Available Si photonics as an integration platform has recently been a focus of optoelectronics research because of the promise of low-cost manufacturing based on the ubiquitous electronics fabrication infrastructure. The key challenge for Si photonic systems is the realization of compact, electrically driven optical gain elements. We review our recent developments in hybrid Si evanescent devices. We have demonstrated electrically pumped lasers, amplifiers, and photodetectors that can provide a low-cost, scalable solution for hybrid integration on a Si platform by using a novel hybrid waveguide architecture, consisting of III-V quantum wells bonded to Si waveguides.

  15. Chaotic mixer improves microarray hybridization.

    Science.gov (United States)

    McQuain, Mark K; Seale, Kevin; Peek, Joel; Fisher, Timothy S; Levy, Shawn; Stremler, Mark A; Haselton, Frederick R

    2004-02-15

    Hybridization is an important aspect of microarray experimental design which influences array signal levels and the repeatability of data within an array and across different arrays. Current methods typically require 24h and use target inefficiently. In these studies, we compare hybridization signals obtained in conventional static hybridization, which depends on diffusional target delivery, with signals obtained in a dynamic hybridization chamber, which employs a fluid mixer based on chaotic advection theory to deliver targets across a conventional glass slide array. Microarrays were printed with a pattern of 102 identical probe spots containing a 65-mer oligonucleotide capture probe. Hybridization of a 725-bp fluorescently labeled target was used to measure average target hybridization levels, local signal-to-noise ratios, and array hybridization uniformity. Dynamic hybridization for 1h with 1 or 10ng of target DNA increased hybridization signal intensities approximately threefold over a 24-h static hybridization. Similarly, a 10- or 60-min dynamic hybridization of 10ng of target DNA increased hybridization signal intensities fourfold over a 24h static hybridization. In time course studies, static hybridization reached a maximum within 8 to 12h using either 1 or 10ng of target. In time course studies using the dynamic hybridization chamber, hybridization using 1ng of target increased to a maximum at 4h and that using 10ng of target did not vary over the time points tested. In comparison to static hybridization, dynamic hybridization reduced the signal-to-noise ratios threefold and reduced spot-to-spot variation twofold. Therefore, we conclude that dynamic hybridization based on a chaotic mixer design improves both the speed of hybridization and the maximum level of hybridization while increasing signal-to-noise ratios and reducing spot-to-spot variation.

  16. UC Davis Fuel Cell, Hydrogen, and Hybrid Vehicle (FCH2V) GATE Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, Paul

    2012-05-31

    This is the final report of the UC Davis Fuel Cell, Hydrogen, and Hybrid Vehicle (FCH2V) GATE Center of Excellence which spanned from 2005-2012. The U.S. Department of Energy (DOE) established the Graduate Automotive Technology Education (GATE) Program, to provide a new generation of engineers and scientists with knowledge and skills to create advanced automotive technologies. The UC Davis Fuel Cell, Hydrogen, and Hybrid Vehicle (FCH2V) GATE Center of Excellence established in 2005 is focused on research, education, industrial collaboration and outreach within automotive technology. UC Davis has had two independent GATE centers with separate well-defined objectives and research programs from 1998. The Fuel Cell Center, administered by ITS-Davis, has focused on fuel cell technology. The Hybrid-Electric Vehicle Design Center (HEV Center), administered by the Department of Mechanical and Aeronautical Engineering, has focused on the development of plug-in hybrid technology using internal combustion engines. The merger of these two centers in 2005 has broadened the scope of research and lead to higher visibility of the activity. UC Davis's existing GATE centers have become the campus's research focal points on fuel cells and hybrid-electric vehicles, and the home for graduate students who are studying advanced automotive technologies. The centers have been highly successful in attracting, training, and placing top-notch students into fuel cell and hybrid programs in both industry and government.

  17. Hybrid polymer microspheres

    Science.gov (United States)

    Rembaum, A.

    1980-01-01

    Techniques have been successfully tested for bonding polymeric spheres, typically 0.1 micron in diameter, to spheres with diameter up to 100 microns. Hybrids are being developed as improved packing material for ion-exchange columns, filters, and separators.

  18. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  19. Hybrid photon detectors

    CERN Document Server

    D'Ambrosio, C

    2003-01-01

    Hybrid photon detectors detect light via vacuum photocathodes and accelerate the emitted photoelectrons by an electric field towards inversely polarized silicon anodes, where they are absorbed, thus producing electron-hole pairs. These, in turn, are collected and generate electronic signals on their ohmic contacts. This review first describes the characteristic properties of the main components of hybrid photon detectors: light entrance windows, photocathodes, and silicon anodes. Then, essential relations describing the trajectories of photoelectrons in electric and magnetic fields and their backscattering from the silicon anodes are derived. Depending on their anode configurations, three families of hybrid photon detectors are presented: hybrid photomultiplier tubes with single anodes for photon counting with high sensitivity and for gamma spectroscopy; multi-anode photon detector tubes with anodes subdivided into square or hexagonal pads for position-sensitive photon detection; imaging silicon pixel array t...

  20. Functional hybrid materials

    National Research Council Canada - National Science Library

    Fahmi, Amir; Pietsch, Torsten; Mendoza, Cesar; Cheval, Nicolas

    2009-01-01

    .... This paper describes our group's achievements towards the development of multifunctional nanostructures via self-assembly of hybrid systems based on the block copolymer PS-b-P4VP and inorganic nanoparticles (NPs...

  1. Hybrid Rocket Technology

    Directory of Open Access Journals (Sweden)

    Sankaran Venugopal

    2011-04-01

    Full Text Available With their unique operational characteristics, hybrid rockets can potentially provide safer, lower-cost avenues for spacecraft and missiles than the current solid propellant and liquid propellant systems. Classical hybrids can be throttled for thrust tailoring, perform in-flight motor shutdown and restart. In classical hybrids, the fuel is stored in the form of a solid grain, requiring only half the feed system hardware of liquid bipropellant engines. The commonly used fuels are benign, nontoxic, and not hazardous to store and transport. Solid fuel grains are not highly susceptible to cracks, imperfections, and environmental temperature and are therefore safer to manufacture, store, transport, and use for launch. The status of development based on the experience of the last few decades indicating the maturity of the hybrid rocket technology is given in brief.Defence Science Journal, 2011, 61(3, pp.193-200, DOI:http://dx.doi.org/10.14429/dsj.61.518

  2. Nitrous Paraffin Hybrid Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nitrous Oxide Paraffin Hybrid engine (N2OP) is a proposed technology designed to provide small launch vehicles with high specific impulse, indefinitely storable...

  3. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  4. Bromine oxidation of a nickel(II) bis(oxime-imine) complex. Evidence for a single-step outer-sphere two-electron transfer

    Energy Technology Data Exchange (ETDEWEB)

    Lappin, A.G.; Osvath, P.; Baral, S.

    1987-09-23

    The kinetics and mechanism of the two-electron oxidation of the sexidentate bis(oxime-imine) complex of nickel(II), (Ni/sup II/L) (I), by bromine have been investigated in bromide ion media over the pH range 3.1-7.6 at 25/sup 0/C and 1.0 M ionic strength. In the presence of an excess of bromine or nickel(II), oxidation is monophasic, and the initial product is (Ni/sup IV/L)/sup 2 +/, a formal nickel(IV) species that undergoes subsequent reactions to give an unknown oxidation product with excess bromine at pH > 6 or to give (Ni/sup III/L)/sup +/ by comproportionation with excess nickel(II) at pH > 5. The sole kinetically important oxidant is Br/sub 2/, and second-order rate constants for reaction of (Ni/sup II/L) and its protonated form (Ni/sup II/LH)/sup +/ are 2.1 x 10/sup 7/ and 7.1 x 10/sup 5/ M/sup -1/ s/sup -1/, respectively. These rate constants are in line with a rate-determining single-electron-transfer reaction, and the proposed mechanism involves formation of a transient ion pair (Ni/sup III/L/sup +/,Br/sub 2//sup -/ in which the rate of subsequent electron transfer is comparable with the rate of ion-pair dissociation. In addition, the pulse-radiolysis technique has been used to investigate the reactions of nickel(II) with Br/sub 2//sup -/ to give (Ni/sup III/L)/sup +/, and rate constants for (Ni/sup II/L) and (Ni/sup II/LH)/sup +/ are 8.5 x 10/sup 8/ and 2.7 x 10/sup 8/ M/sup -1/ S/sup -1/, respectively, at 21/sup 0/C. 34 references, 3 figures, 3 tables.

  5. Hybridity in Disgrace

    Institute of Scientific and Technical Information of China (English)

    刘建平

    2015-01-01

    John Maxwell Coetzee's masterpiece-Disgrace is the representative work about post colonialism.The novel describes a series of disgraceful events happened between the white and the black in the post apartheid South Africa.The famous literature theory-hybridity of Homi K.Bhabha is the very key theory to analyze the work.In post apartheid South Africa,hybridity is the only way for the white and the black to coexist.

  6. Hybrid Baryon Signatures

    CERN Document Server

    Page, P R

    2000-01-01

    We discuss whether a low-lying hybrid baryon should be defined as a three quark - gluon bound state or as three quarks moving on an excited adiabatic potential. We show that the latter definition becomes exact, not only for very heavy quarks, but also for specific dynamics. We review the literature on the signatures of hybrid baryons, with specific reference to strong hadronic decays, electromagnetic couplings, diffractive production and production in psi decay.

  7. Hybrid vertical cavity laser

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2010-01-01

    A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide.......A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide....

  8. Requirements for Hybrid Cosimulation

    Science.gov (United States)

    2014-08-16

    hybrid cosimulation version of the Functional Mockup Interface (FMI) standard. A cosimulation standard de nes interfaces that enable diverse simulation...cosimulation standards, and specifically provides guidance for development of a hybrid cosimulation version of the Functional Mockup Interface (FMI) standard...V. Peetz, and S. Wolf. The functional mockup interface for tool independent exchange of simulation models. In Proc. of the 8-th International

  9. The Hybrids of Postmodernism

    Directory of Open Access Journals (Sweden)

    Dana BĂDULESCU

    2014-09-01

    Full Text Available Hybridization is a fundamental characteristic of postmodernism, included by Ihab Hassan in his “catena” of features. This paper looks into the hybrids of postmodernism, which are the result of migration, displacement and uprooting, the re-visitation of myths, folklore and legends, or projections of their author’s imagination. The hybrids used as examples here are drawn from several novels written by Salman Rushdie, especially The Satanic Verses, two short stories, one by Márquez and the other by Donald Barthelme, Borges’s Book of Imaginary Beings, Cărtărescu’s Encyclopaedia of Dragons and Michelle Cliff’s No Telephone to Heaven. Diverse as they may be, these hybrids emphasize a defining characteristic of postmodernism, which is its pluralism. I conclude that the hybrids of postmodernism are aesthetically or politically subversive. Besides, what makes them difficult to grasp is their unfixed and protean nature. They ask for high leaps of the imagination, a total suspension of disbelief and a complete surrender to the powerful seduction of imagination on the reader’s part.

  10. Research on Hybrid Vehicle Drivetrain

    Science.gov (United States)

    Xie, Zhongzhi

    Hybrid cars as a solution to energy saving, emission reduction measures, have received widespread attention. Motor drive system as an important part of the hybrid vehicles as an important object of study. Based on the hybrid electric vehicle powertrain control system for permanent magnet synchronous motor as the object of study. Can be applied to hybrid car compares the characteristics of traction motors, chose permanent magnet synchronous Motors as drive motors for hybrid vehicles. Building applications in hybrid cars in MATLAB/Simulink simulation model of permanent-magnet synchronous motor speed control system and analysis of simulation results.

  11. for hybrid dynamical systems

    Directory of Open Access Journals (Sweden)

    Wassim M. Haddad

    2001-01-01

    Full Text Available In this paper we develop a unified dynamical systems framework for a general class of systems possessing left-continuous flows; that is, left-continuous dynamical systems. These systems are shown to generalize virtually all existing notions of dynamical systems and include hybrid, impulsive, and switching dynamical systems as special cases. Furthermore, we generalize dissipativity, passivity, and nonexpansivity theory to left-continuous dynamical systems. Specifically, the classical concepts of system storage functions and supply rates are extended to left-continuous dynamical systems providing a generalized hybrid system energy interpretation in terms of stored energy, dissipated energy over the continuous-time dynamics, and dissipated energy over the resetting events. Finally, the generalized dissipativity notions are used to develop general stability criteria for feedback interconnections of left-continuous dynamical systems. These results generalize the positivity and small gain theorems to the case of left-continuous, hybrid, and impulsive dynamical systems.

  12. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Rönnkö, M.; Ravn, Anders Peter; Sere, K.

    2003-01-01

    In this paper we investigate the use of action systems with differential actions in the specifcation of hybrid systems. As the main contribution we generalize the definition of a differential action, allowing the use of arbitrary relations over model variables and their time-derivatives in modell......In this paper we investigate the use of action systems with differential actions in the specifcation of hybrid systems. As the main contribution we generalize the definition of a differential action, allowing the use of arbitrary relations over model variables and their time...... parallel composition. Moreover, as the strength of the action system formalism is the support for stepwise development by refinement, we investigate refinement involving a differential action. We show that, due to the predicate transformer semantics, standard action refinement techniques apply also...... to the differential action, thus, allowing stepwise development of hybrid systems Udgivelsesdato: JAN 1...

  13. Conditional Hybrid Nonclassicality

    Science.gov (United States)

    Agudelo, E.; Sperling, J.; Costanzo, L. S.; Bellini, M.; Zavatta, A.; Vogel, W.

    2017-09-01

    We derive and implement a general method to characterize the nonclassicality in compound discrete- and continuous-variable systems. For this purpose, we introduce the operational notion of conditional hybrid nonclassicality which relates to the ability to produce a nonclassical continuous-variable state by projecting onto a general superposition of discrete-variable subsystem. We discuss the importance of this form of quantumness in connection with interfaces for quantum communication. To verify the conditional hybrid nonclassicality, a matrix version of a nonclassicality quasiprobability is derived and its sampling approach is formulated. We experimentally generate an entangled, hybrid Schrödinger cat state, using a coherent photon-addition process acting on two temporal modes, and we directly sample its nonclassicality quasiprobability matrix. The introduced conditional quantum effects are certified with high statistical significance.

  14. Porosity in hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, D.W.; Beaucage, G.; Loy, D. [Sandia National Labs., Albuquerque, NM (United States)

    1995-12-31

    Multicomponent, or hybrid composites are emerging as precursors to porous materials. Sacrifice of an ephemeral phase can be used to generate porosity, the nature of which depends on precursor structure. Retention of an organic constituent, on the other hand, can add desirable toughness to an otherwise brittle ceramic. We use small-angle x-ray and neutron scattering to examine porosity in both simple and hybrid materials. We find that microphase separation controls porosity in almost all systems studied. Pore distributions are controlled by the detailed bonding within and between phases as well as the flexibility of polymeric constituents. Thus hybridization opens new regions of pore distributions not available in simple systems. We look at several sacrificial concepts and show that it is possible to generate multimodal pore size distributions due to the complicated phase structure in the precursor.

  15. Photoproduction of Hybrid Mesons

    CERN Document Server

    Barnes, T

    1998-01-01

    In this contribution I discuss prospects for photoproducing hybrid mesons at CEBAF, based on recent model results and experimental indications of possible hybrids. One excellent opportunity appears to be a search for the I=1, JPC=2+-, neutral "(b2)o" hybrid in (a2 pi)o through diffractive photoproduction. Other notable possibilities accessible through pi+ or pio exchange photoproduction are I=1, JPC=1-+, charged "pi1+" in f1 pi+, (b1 pi)+ and (rho pi)+; piJ(1770)+ in f2 pi+ and (b1 pi)+; pi(1800)+ in f0 pi+, f2 pi+, omega rho+ and (rho pi)+; a1 in f1 pi+ and f2 pi+; and omega in (rho pi)o, omega eta and (K1 K)o.

  16. Smart hybrid rotary damper

    Science.gov (United States)

    Yang, C. S. Walter; DesRoches, Reginald

    2014-03-01

    This paper develops a smart hybrid rotary damper using a re-centering smart shape memory alloy (SMA) material as well as conventional energy-dissipating metallic plates that are easy to be replaced. The ends of the SMA and steel plates are inserted in the hinge. When the damper rotates, all the plates bend, providing energy dissipating and recentering characteristics. Such smart hybrid rotary dampers can be installed in structures to mitigate structural responses and to re-center automatically. The damaged energy-dissipating plates can be easily replaced promptly after an external excitation, reducing repair time and costs. An OpenSEES model of a smart hybrid rotary was established and calibrated to reproduce the realistic behavior measured from a full-scale experimental test. Furthermore, the seismic performance of a 3-story moment resisting model building with smart hybrid rotary dampers designed for downtown Los Angeles was also evaluated in the OpenSEES structural analysis software. Such a smart moment resisting frame exhibits perfect residual roof displacement, 0.006", extremely smaller than 18.04" for the conventional moment resisting frame subjected to a 2500 year return period ground motion for the downtown LA area (an amplified factor of 1.15 on Kobe earthquake). The smart hybrid rotary dampers are also applied into an eccentric braced steel frame, which combines a moment frame system and a bracing system. The results illustrate that adding smart hybrid rotaries in this braced system not only completely restores the building after an external excitation, but also significantly reduces peak interstory drifts.

  17. Analog and hybrid computing

    CERN Document Server

    Hyndman, D E

    2013-01-01

    Analog and Hybrid Computing focuses on the operations of analog and hybrid computers. The book first outlines the history of computing devices that influenced the creation of analog and digital computers. The types of problems to be solved on computers, computing systems, and digital computers are discussed. The text looks at the theory and operation of electronic analog computers, including linear and non-linear computing units and use of analog computers as operational amplifiers. The monograph examines the preparation of problems to be deciphered on computers. Flow diagrams, methods of ampl

  18. Hybrid Weyl semimetal

    Science.gov (United States)

    Li, Fei-Ye; Luo, Xi; Dai, Xi; Yu, Yue; Zhang, Fan; Chen, Gang

    2016-09-01

    We construct a tight-binding model realizing one pair of Weyl nodes and three distinct Weyl semimetals. In the type-I (type-II) Weyl semimetal, both nodes belong to type-I (type-II) Weyl nodes. In addition, there exists a third type, previously undiscovered and dubbed "hybrid Weyl semimetal", in which one Weyl node is of type I while the other is of type II. For the hybrid Weyl semimetal, we further demonstrate the bulk Fermi surfaces and the topologically protected surface states, analyze the unique Landau-level structure and quantum oscillation, and discuss the conditions for possible material realization.

  19. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  20. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  1. THERMALLY CLEAVABLE HYBRID MATERIALS

    Directory of Open Access Journals (Sweden)

    Constantin Gaina

    2011-12-01

    Full Text Available Thermally cleavable hybrid materials were prepared by the Diels-Alder cycloaddition reaction of poly(vinyl furfural to N phenylmaleimido-N’-(triethoxysilylpropylurea followed by the sol-gel condensation reaction of trietoxysilyl groups with water and acetic acid. Thermal and dynamic mechanical analysis, dielectric and FTIR spectroscopy were used to characterize the structure and properties of the composites. The size of the inorganic silica particles in the hybrid material varied dependent on the silica content. The DSC study of the prepared materials revealed that the cleavage process of the formed cycloadducts takes place at temperatures varying between 143-165°C and is an endothermic process.

  2. The hybrid BCI

    Directory of Open Access Journals (Sweden)

    Gert Pfurtscheller

    2010-04-01

    Full Text Available Nowadays, everybody knows what a hybrid car is. A hybrid car normally has 2 engines, its main purpose being to enhance energy efficiency and reduce CO2 output. Similarly, a typical hybrid brain-computer interface (BCI is also composed of 2 BCIs or at least one BCI and another system. Such a hybrid BCI, like any BCI, must fulfil the following four criteria: (i the device must rely on signals recorded directly from the brain; (ii there must be at least one recordable brain signal that the user can intentionally modulate to effect goal-directed behaviour; (iii real time processing; and (iv the user must obtain feedback. This paper introduces some hybrid BCIs which have already been published or are currently in development or validation, and some concepts for future work. The BCIs described classify 2 EEG patterns: One is the event-related (desynchronisation (ERD, ERS of sensorimotor rhythms, and the other is the steady-state visual evoked potential (SSVEP. The hybrid BCI can either have more than one input whereby the inputs are typically processed simultaneously or operate 2 systems sequentially, whereby the first system can act as a “brain switch”. In the case of self-paced operation of a SSVEP-based hand orthosis control with an motor imagery-based switch it was possible to reduce the rate of false positives during resting periods by about 50% compared to the SSVEP BCI alone. It is shown that such a brain switch can also rely on hemodynamic changes measured through near-infrared spectroscopy (NIRS. Another interesting approach is a hybrid BCI with simultaneous operations of ERD- and SSVEP-based BCIs. Here it is important to prove the existing promising offline simulation results with online experiments. Hybrid BCIs can also use one brain signal and another input. Such an additional input can be a physiological signal like the heart rate but also a signal from an external device like, an eye gaze control system.

  3. A Mathematical Approach to Hybridization

    Science.gov (United States)

    Matthews, P. S. C.; Thompson, J. J.

    1975-01-01

    Presents an approach to hybridization which exploits the similarities between the algebra of wave functions and vectors. This method will account satisfactorily for the number of orbitals formed when applied to hybrids involving the s and p orbitals. (GS)

  4. Hybrid Ventilation Air Flow Process

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols

    The scope of this annex is therefore to obtain better knowledge of the use of hybrid ventilation technologies. The annex focus on development of control strategies for hybrid ventilation, on development of methods to predict hybrid ventilation performance in office buildings and on implementation...

  5. (Hybrid) Baryons Symmetries and Masses

    CERN Document Server

    Page, P R

    1999-01-01

    We construct (hybrid) baryons in the flux-tube model of Isgur and Paton. In the limit of adiabatic quark motion, we build proper eigenstates of orbital angular momentum and construct the flavour, spin and J^P of hybrid baryons from the symmetries of the system. The lowest mass hybrid baryon is estimated at approximately 2 GeV.

  6. Improved hybrid rocket fuel

    Science.gov (United States)

    Dean, David L.

    1995-01-01

    McDonnell Douglas Aerospace, as part of its Independent R&D, has initiated development of a clean burning, high performance hybrid fuel for consideration as an alternative to the solid rocket thrust augmentation currently utilized by American space launch systems including Atlas, Delta, Pegasus, Space Shuttle, and Titan. It could also be used in single stage to orbit or as the only propulsion system in a new launch vehicle. Compared to solid propellants based on aluminum and ammonium perchlorate, this fuel is more environmentally benign in that it totally eliminates hydrogen chloride and aluminum oxide by products, producing only water, hydrogen, nitrogen, carbon oxides, and trace amounts of nitrogen oxides. Compared to other hybrid fuel formulations under development, this fuel is cheaper, denser, and faster burning. The specific impulse of this fuel is comparable to other hybrid fuels and is between that of solids and liquids. The fuel also requires less oxygen than similar hybrid fuels to produce maximum specific impulse, thus reducing oxygen delivery system requirements.

  7. Workshop on hybrid rice

    Institute of Scientific and Technical Information of China (English)

    TANZhijun

    1994-01-01

    FAO, in collaboration with FEDEARROZ in Colombia and EMBRAPA / CNPAF in Brail, organized a workshop on the Establishment of a Coorperative Research Network on Hybrid Rice in Latin America and the Caribbean held from Mar 16 to 18, 1994 at EMBRAPA/CNPAF in Brazil. Dr MAO Changxiang,

  8. Teelt van hybride wintertarwerassen

    NARCIS (Netherlands)

    Timmer, R.D.; Paauw, J.G.M.

    2003-01-01

    Om de mogelijkheden van de teelt van hybride wintertarwerassen onder Nederlandse omstandigheden in beeld te brengen zijn er van 2000-2002 proeven uitgevoerd op het PPO-proefbedrijf te Lelystad. In deze proeven zijn een 4-tal hybriderassen (Hybnos, Hyno-braba, Hyno-esta, Mercury) vergeleken met een s

  9. Organics go hybrid

    Science.gov (United States)

    Lanzani, Guglielmo; Petrozza, Annamaria; Caironi, Mario

    2017-01-01

    From displays to solar cells, the field of organic optoelectronics has come a long way over the past 50 years, but the realization of an electrically pumped organic laser remains elusive. The answer may lie with hybrid organic-inorganic materials called perovskites.

  10. Hybrid-secure MPC 

    DEFF Research Database (Denmark)

    Lucas, Christoph; Raub, Dominik; Maurer, Ueli

    2010-01-01

    Most protocols for distributed, fault-tolerant computation, or multi-party computation (MPC), provide security guarantees in an all-or-nothing fashion. In contrast, a hybrid-secure protocol provides different security guarantees depending on the set of corrupted parties and the computational powe...

  11. Indexical Hybrid Tense Logic

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Jørgensen, Klaus Frovin

    2012-01-01

    In this paper we explore the logic of now, yesterday, today and tomorrow by combining the semantic approach to indexicality pioneered by Hans Kamp [9] and refined by David Kaplan [10] with hybrid tense logic. We first introduce a special now nominal (our @now corresponds to Kamp’s original now...

  12. Nuclear hybrid energy infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Vivek; Tawfik, Magdy S.

    2015-02-01

    The nuclear hybrid energy concept is becoming a reality for the US energy infrastructure where combinations of the various potential energy sources (nuclear, wind, solar, biomass, and so on) are integrated in a hybrid energy system. This paper focuses on challenges facing a hybrid system with a Small Modular Reactor at its core. The core of the paper will discuss efforts required to develop supervisory control center that collects data, supports decision-making, and serves as an information hub for supervisory control center. Such a center will also be a model for integrating future technologies and controls. In addition, advanced operations research, thermal cycle analysis, energy conversion analysis, control engineering, and human factors engineering will be part of the supervisory control center. Nuclear hybrid energy infrastructure would allow operators to optimize the cost of energy production by providing appropriate means of integrating different energy sources. The data needs to be stored, processed, analyzed, trended, and projected at right time to right operator to integrate different energy sources.

  13. Hybrid printed electronics

    NARCIS (Netherlands)

    Koetse, M.; Smits, E.; Rubingh, E.; Teunissen, P.; Kusters, R.; Abbel, R.; Brand, J. van den

    2016-01-01

    Although many electronic functionalities can be realized by printed or organic electronics, short-term marketable products often require robust, reproducible, and nondisturbing technologies. In this chapter we show how hybrid electronics, a combination of printed circuitry, thin-film electronics,

  14. Hybrid keyword search auctions

    KAUST Repository

    Goel, Ashish

    2009-01-01

    Search auctions have become a dominant source of revenue generation on the Internet. Such auctions have typically used per-click bidding and pricing. We propose the use of hybrid auctions where an advertiser can make a per-impression as well as a per-click bid, and the auctioneer then chooses one of the two as the pricing mechanism. We assume that the advertiser and the auctioneer both have separate beliefs (called priors) on the click-probability of an advertisement. We first prove that the hybrid auction is truthful, assuming that the advertisers are risk-neutral. We then show that this auction is superior to the existing per-click auction in multiple ways: 1. We show that risk-seeking advertisers will choose only a per-impression bid whereas risk-averse advertisers will choose only a per-click bid, and argue that both kind of advertisers arise naturally. Hence, the ability to bid in a hybrid fashion is important to account for the risk characteristics of the advertisers. 2. For obscure keywords, the auctioneer is unlikely to have a very sharp prior on the click-probabilities. In such situations, we show that having the extra information from the advertisers in the form of a per-impression bid can result in significantly higher revenue. 3. An advertiser who believes that its click-probability is much higher than the auctioneer\\'s estimate can use per-impression bids to correct the auctioneer\\'s prior without incurring any extra cost. 4. The hybrid auction can allow the advertiser and auctioneer to implement complex dynamic programming strategies to deal with the uncertainty in the click-probability using the same basic auction. The per-click and per-impression bidding schemes can only be used to implement two extreme cases of these strategies. As Internet commerce matures, we need more sophisticated pricing models to exploit all the information held by each of the participants. We believe that hybrid auctions could be an important step in this direction. The

  15. A two-center comparative study of plastic and lumen-apposing large diameter self-expandable metallic stents in endoscopic ultrasound-guided drainage of pancreatic fluid collections

    Science.gov (United States)

    Ang, Tiing Leong; Kongkam, Pradermchai; Kwek, Andrew Boon Eu; Orkoonsawat, Piyachai; Rerknimitr, Rungsun; Fock, Kwong Ming

    2016-01-01

    Background and Objectives: Endoscopic ultrasound-guided drainage of walled-off pancreatic fluid collections (PFCs) (pseudocyst [PC]; walled-off necrosis [WON]) utilizes double pigtail plastic stents (PS) and the newer large diameter fully covered self-expandable stents (FCSEMS) customized for PFC drainage. This study examined the impact of type of stent on clinical outcomes and costs. Patients and Methods: Retrospective two-center study. Outcome variables were technical and clinical success, need for repeat procedures, need for direct endoscopic necrosectomy (DEN), and procedure-related costs. Results: A total of 49 (PC: 31, WON: 18) patients were analyzed. Initially, PS was used in 37 and FCSEMS in 12. Repeat transmural drainage was required in 14 (PS: 13 [9 treated with PS, 4 treated with FCSEMS]; FCSEMS: 1 [treated with PS]) due to stent migration (PS: 3; FCSEMS: 1) or inadequate drainage (PS: 10). Technical success was 100%. Initial clinical success was 64.9% (25/38) for PS versus 91.7% (11/12) for FCSEMS (P = 0.074). With repeat transmural stenting, final clinical success was achieved in 94.6% and 100%, respectively (P = 0.411). Compared to FCSEMS, PS was associated with greater need for repeat drainage (34.2% vs. 6.3%, P = 0.032). The need for and frequency of DEN was similar between both groups, but PS required more frequent balloon dilatation. PS was significantly cheaper for noninfected PC. Costs were similar for infected PC and WON. Conclusion: PS was associated with a higher need for a second drainage procedure to achieve clinical success. The use of FCSEMS did not increase procedural costs for infected PC and WON.

  16. Experimental cross sections for two-electron capture into nitrogen autoionising states in Nsup(q+) (q=6,7) on He and H/sub 2/ collisions at 10. 5q keV

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, A.; Benoit-Cattin, P.; Gleizes, A.; Marrakchi, A.I.; Dousson, S.; Hitz, D.

    1985-07-01

    Singly differential cross sections for two-electron capture into autoionising states (nl,n'l') with n=2,3,4 and n'>=n in Nsup(q+) (q=6,7) on He and H/sub 2/ collisions have been measured at 10,5q ke V collision energy and an observation angle thetasub(lab)=11.6/sup 0/. Total cross sections are estimated assuming isotropic angular distributions. (orig.).

  17. Ants exhibit asymmetric hybridization in a mosaic hybrid zone.

    Science.gov (United States)

    Purcell, Jessica; Zahnd, Sacha; Athanasiades, Anouk; Türler, Rebecca; Chapuisat, Michel; Brelsford, Alan

    2016-10-01

    Research on hybridization between species provides unparalleled insights into the pre- and postzygotic isolating mechanisms that drive speciation. In social organisms, colony-level incompatibilities may provide additional reproductive barriers not present in solitary species, and hybrid zones offer an opportunity to identify these barriers. Here, we use genotyping-by-sequencing to sequence hundreds of markers in a hybrid zone between two socially polymorphic ant species, Formica selysi and Formica cinerea. We characterize the zone, determine the frequency of hybrid workers, infer whether hybrid queens or males are produced and investigate whether hybridization is influenced by colony social organization. We also compare cuticular hydrocarbon profiles and aggression levels between the two species. The hybrid zone exhibits a mosaic structure. The asymmetric distribution of hybrids skewed towards F. cinerea suggests a pattern of unidirectional nuclear gene flow from F. selysi into F. cinerea. The occurrence of backcrossed individuals indicates that hybrid queens and/or males are fertile, and the presence of the F. cinerea mitochondrial haplotype in 97% of hybrids shows that successful F1 hybrids will generally have F. cinerea mothers and F. selysi fathers. We found no evidence that social organization contributes to speciation, because hybrids occur in both single-queen and multiple-queen colonies. Strongly differentiated cuticular hydrocarbon profiles and heightened interspecific aggression further reveal that species recognition cues are both present and perceived. The discovery of fertile hybrids and asymmetrical gene flow is unusual in ants, and this hybrid zone will therefore provide an ideal system with which to investigate speciation in social insects.

  18. Energy Efficiency Comparison between Hydraulic Hybrid and Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jia-Shiun Chen

    2015-05-01

    Full Text Available Conventional vehicles tend to consume considerable amounts of fuel, which generates exhaust gases and environmental pollution during intermittent driving cycles. Therefore, prospective vehicle designs favor improved exhaust emissions and energy consumption without compromising vehicle performance. Although pure electric vehicles feature high performance and low pollution characteristics, their limitations are their short driving range and high battery costs. Hybrid electric vehicles (HEVs are comparatively environmentally friendly and energy efficient, but cost substantially more compared with conventional vehicles. Hydraulic hybrid vehicles (HHVs are mainly operated using engines, or using alternate combinations of engine and hydraulic power sources while vehicles accelerate. When the hydraulic system accumulator is depleted, the conventional engine reengages; concurrently, brake-regenerated power is recycled and reused by employing hydraulic motor–pump modules in circulation patterns to conserve fuel and recycle brake energy. This study adopted MATLAB Simulink to construct complete HHV and HEV models for backward simulations. New European Driving Cycles were used to determine the changes in fuel economy. The output of power components and the state-of-charge of energy could be retrieved. Varying power component models, energy storage component models, and series or parallel configurations were combined into seven different vehicle configurations: the conventional manual transmission vehicle, series hybrid electric vehicle, series hydraulic hybrid vehicle, parallel hybrid electric vehicle, parallel hydraulic hybrid vehicle, purely electric vehicle, and hydraulic-electric hybrid vehicle. The simulation results show that fuel consumption was 21.80% lower in the series hydraulic hybrid vehicle compared to the series hybrid electric vehicle; additionally, fuel consumption was 3.80% lower in the parallel hybrid electric vehicle compared to the

  19. Phoxonic Hybrid Superlattice.

    Science.gov (United States)

    Alonso-Redondo, Elena; Huesmann, Hannah; El Boudouti, El-Houssaine; Tremel, Wolfgang; Djafari-Rouhani, Bahram; Butt, Hans-Juergen; Fytas, George

    2015-06-17

    We studied experimentally and theoretically the direction-dependent elastic and electromagnetic wave propagation in a supported film of hybrid PMMA (poly[methyl-methacrylate])-TiO2 superlattice (SL). In the direction normal to the layers, this one-dimensional periodic structure opens propagation band gaps for both hypersonic (GHz) phonons and near-UV photons. The high mismatch of elastic and optical impedance results in a large dual phoxonic band gap. The presence of defects inherent to the spin-coating fabrication technique is sensitively manifested in the band gap region. Utilizing Brillouin light scattering, phonon propagation along the layers was observed to be distinctly different from propagation normal to them and can, under certain conditions (SL thickness and substrate elasticity), reveal the nanomechanical properties of the constituent layers. Besides the first realization of unidirectional phoxonic behavior, hybrid (soft-hard) periodic materials are a promising simple platform for opto-acoustic interactions and applications such as filters and Bragg mirrors.

  20. The Power of Hybridization

    CERN Document Server

    CERN. Geneva

    2011-01-01

    Programming languages always seem to do some things well but not others: Python punts when it comes to user interfaces, Java’s artificial complexity prevents rapid development and produces tangles, and it will be awhile before we see benefits from C++ concurrency work. The cognitive load of languages and their blind spots increases the cost of experimentation, impeding your ability to fail fast and iterate. If you use a single language to solve your problem, you are binding yourself to the worldview limitations and the mistakes made by the creator of that language. Consider increasing your wiggle room by crossing language boundaries, complementing a language that is powerful in one area with a different language powerful in another. Language hybridization can speed development to quickly discover your real problems, giving you more time to fix them. After making a case for hybridizing your thinking in general, I will present a number of simple examples; first showing the benefits of using other languages...

  1. A Pseudoscalar Hybrid Meson?

    CERN Document Server

    Page, P R

    1996-01-01

    New experimental information on the non--exotic J^{PC} = 0^{-+} isovector seen at 1.8 GeV by VES yields convincing evidence of its excited gluonic (hybrid) nature when a critical study of alternative quarkonium assignments is made in the context of ^3 P_0 decay by flux--tube breaking. Production of this gluonic excitation via meson exchange is promising, although its two photon production vanishes.

  2. Military Hybrid Vehicle Survey

    Science.gov (United States)

    2011-08-03

    Furthermore, a standard duty cycle that is accepted for measuring fuel economy does not exist nor does a focus towards a particular technology. This...expanded into mild hybrid with the addition of a clutch connecting the generator to the transmission and additional energy storage [16-17...speed control and one for engine/generator torque [35]. Urban, Highway, Composite 33%, 27.9%, 49% General vehicle simulation [30]. Urban 19.0

  3. Fibonacci-Pell Hybridities

    Science.gov (United States)

    Koshy, Thomas; Gao, Zhenguang

    2012-01-01

    We develop a recurrence satisfied by the Fibonacci and Pell families. We then use it to find explicit formulae and generating functions for the hybrids "F[subscript n]P[subscript n]", "L[subscript n]P[subscript n]", "F[subscript n]Q[subscript n]" and "L[subscript n]Q[subscript n]", where "F[subscript n]", "L[subscript n]", "P[subscript n]" and…

  4. Hybrid electroluminescent devices

    Science.gov (United States)

    Shiang, Joseph John; Duggal, Anil Raj; Michael, Joseph Darryl

    2010-08-03

    A hybrid electroluminescent (EL) device comprises at least one inorganic diode element and at least one organic EL element that are electrically connected in series. The absolute value of the breakdown voltage of the inorganic diode element is greater than the absolute value of the maximum reverse bias voltage across the series. The inorganic diode element can be a power diode, a Schottky barrier diode, or a light-emitting diode.

  5. Hybrid undulator numerical optimization

    Energy Technology Data Exchange (ETDEWEB)

    Hairetdinov, A.H. [Kurchatov Institute, Moscow (Russian Federation); Zukov, A.A. [Solid State Physics Institute, Chernogolovka (Russian Federation)

    1995-12-31

    3D properties of the hybrid undulator scheme arc studied numerically using PANDIRA code. It is shown that there exist two well defined sets of undulator parameters which provide either maximum on-axis field amplitude or minimal higher harmonics amplitude of the basic undulator field. Thus the alternative between higher field amplitude or pure sinusoidal field exists. The behavior of the undulator field amplitude and harmonics structure for a large set of (undulator gap)/(undulator wavelength) values is demonstrated.

  6. Asymmetric Hybrid Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Chumanov, George [Clemson Univ., SC (United States)

    2015-11-05

    Hybrid Nanoparticles (AHNs) are rationally-designed multifunctional nanostructures and novel building blocks for the next generation of advanced materials and devices. Nanoscale materials attract considerable interest because of their unusual properties and potential for practical applications. Most of the activity in this field is focused on the synthesis of homogeneous nanoparticles from metals, metal oxides, semiconductors, and polymers. It is well recognized that properties of nanoparticles can be further enhanced if they are made as hybrid structures. This program is concerned with the synthesis, characterization, and application of such hybrid structures termed AHNs. AHNs are composed of a homogeneous core and several caps of different materials deposited on its surface (Fig. 1). Combined properties of the core and the caps as well as new properties that arise from core-cap and cap-cap interactions render AHNs multifunctional. In addition, specific chemical reactivity of the caps enables directional self-assembly of AHNs into complex architectures that are not possible with only spherical nanoparticles.

  7. Hybrid Keyword Search Auctions

    CERN Document Server

    Goel, Ashish

    2008-01-01

    Search auctions have become a dominant source of revenue generation on the Internet. Such auctions have typically used per-click bidding and pricing. We propose the use of hybrid auctions where an advertiser can make a per-impression as well as a per-click bid, and the auctioneer then chooses one of the two as the pricing mechanism. We assume that the advertiser and the auctioneer both have separate beliefs (called priors) on the click-probability of an advertisement. We first prove that the hybrid auction is truthful, assuming that the advertisers are risk-neutral. We then show that this auction is superior to the existing per-click auction in multiple ways: 1) It takes into account the risk characteristics of the advertisers. 2) For obscure keywords, the auctioneer is unlikely to have a very sharp prior on the click-probabilities. In such situations, the hybrid auction can result in significantly higher revenue. 3) An advertiser who believes that its click-probability is much higher than the auctioneer's es...

  8. Printed hybrid systems

    Science.gov (United States)

    Karioja, Pentti; Mäkinen, Jukka-Tapani; Keränen, Kimmo; Aikio, Janne; Alajoki, Teemu; Jaakola, Tuomo; Koponen, Matti; Keränen, Antti; Heikkinen, Mikko; Tuomikoski, Markus; Suhonen, Riikka; Hakalahti, Leena; Kopola, Pälvi; Hast, Jukka; Liedert, Ralf; Hiltunen, Jussi; Masuda, Noriyuki; Kemppainen, Antti; Rönkä, Kari; Korhonen, Raimo

    2012-04-01

    This paper presents research activities carried out at VTT Technical Research Centre of Finland in the field of hybrid integration of optics, electronics and mechanics. Main focus area in our research is the manufacturing of electronic modules and product structures with printed electronics, film-over-molding and polymer sheet lamination technologies and the goal is in the next generation of smart systems utilizing monolithic polymer packages. The combination of manufacturing technologies such as roll-to-roll -printing, injection molding and traditional component assembly is called Printed Hybrid Systems (PHS). Several demonstrator structures have been made, which show the potential of polymer packaging technology. One demonstrator example is a laminated structure with embedded LED chips. Element thickness is only 0.3mm and the flexible stack of foils can be bent in two directions after assembly process and was shaped curved using heat and pressure. The combination of printed flexible circuit boards and injection molding has also been demonstrated with several functional modules. The demonstrators illustrate the potential of origami electronics, which can be cut and folded to 3D shapes. It shows that several manufacturing process steps can be eliminated by Printed Hybrid Systems technology. The main benefits of this combination are small size, ruggedness and conformality. The devices are ideally suited for medical applications as the sensitive electronic components are well protected inside the plastic and the structures can be cleaned easily due to the fact that they have no joints or seams that can accumulate dirt or bacteria.

  9. Hybrid2 - The hybrid power system simulation model

    Energy Technology Data Exchange (ETDEWEB)

    Baring-Gould, E.I.; Green, H.J.; Dijk, V.A.P. van [National Renewable Energy Lab., Golden, CO (United States); Manwell, J.F. [Univ. of Massachusetts, Amherst, MA (United States)

    1996-12-31

    There is a large-scale need and desire for energy in remote communities, especially in the developing world; however the lack of a user friendly, flexible performance prediction model for hybrid power systems incorporating renewables hindered the analysis of hybrids as options to conventional solutions. A user friendly model was needed with the versatility to simulate the many system locations, widely varying hardware configurations, and differing control options for potential hybrid power systems. To meet these ends, researchers from the National Renewable Energy Laboratory (NREL) and the University of Massachusetts (UMass) developed the Hybrid2 software. This paper provides an overview of the capabilities, features, and functionality of the Hybrid2 code, discusses its validation and future plans. Model availability and technical support provided to Hybrid2 users are also discussed. 12 refs., 3 figs., 4 tabs.

  10. Electrochemical transduction of DNA hybridization at modified electrodes by using an electroactive pyridoacridone intercalator.

    Science.gov (United States)

    Bouffier, Laurent; Wang, Bingquan Stuart; Roget, André; Livache, Thierry; Demeunynck, Martine; Mailley, Pascal

    2014-02-01

    A synthetic redox probe structurally related to natural pyridoacridones was designed and electrochemically characterised. These heterocycles behave as DNA intercalators due to their extended planar structure that promotes stacking in between nucleic acid base pairs. Electrochemical characterization by cyclic voltammetry revealed a quasi-reversible electrochemical behaviour occurring at a mild negative potential in aqueous solution. The study of the mechanism showed that the iminoquinone redox moiety acts similarly to quinone involving a two-electron reduction coupled with proton transfer. The easily accessible potential region with respect to aqueous electro-inactive window makes the pyridoacridone ring suitable for the indirect electrochemical detection of chemically unlabelled DNA. Its usefulness as electrochemical hybridization indicator was assessed on immobilised DNA and compared to doxorubicin. The voltamperometric response of the intercalator acts as an indicator of the presence of double-stranded DNA at the electrode surface and allows the selective transduction of immobilised oligonucleotide hybridization at both macro- and microscale electrodes.

  11. Hybrid CPU/GPU Integral Engine for Strong-Scaling Ab Initio Methods.

    Science.gov (United States)

    Kussmann, Jörg; Ochsenfeld, Christian

    2017-07-11

    We present a parallel integral algorithm for two-electron contributions occurring in Hartree-Fock and hybrid density functional theory that allows for a strong scaling parallelization on inhomogeneous compute clusters. With a particular focus on graphic processing units, we show that our approach allows an efficient use of CPUs and graphics processing units (GPUs) simultaneously, although the different architectures demand conflictive strategies in order to ensure efficient program execution. Furthermore, we present a general strategy to use large basis sets like quadruple-ζ split valence on GPUs and investigate the balance between CPUs and GPUs depending on l-quantum numbers of the corresponding basis functions. Finally, we present first illustrative calculations using a hybrid CPU/GPU environment and demonstrate the strong-scaling performance of our parallelization strategy also for pure CPU-based calculations.

  12. First-Order Hybrid Logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Hybrid logic is an extension of modal logic which allows us to refer explicitly to points of the model in the syntax of formulas. It is easy to justify interest in hybrid logic on applied grounds, with the usefulness of the additional expressive power. For example, when reasoning about time one...... often wants to build up a series of assertions about what happens at a particular instant, and standard modal formalisms do not allow this. What is less obvious is that the route hybrid logic takes to overcome this problem often actually improves the behaviour of the underlying modal formalism....... For example, it becomes far simpler to formulate proof-systems for hybrid logic, and completeness results can be proved of a generality that is simply not available in modal logic. That is, hybridization is a systematic way of remedying a number of known deficiencies of modal logic. First-order hybrid logic...

  13. Hybridization in geese: a review

    OpenAIRE

    Ottenburghs, Jente; Van Hooft, Pim; van Wieren, Sipke E.; Ydenberg, Ronald C; Herbert H. T. Prins

    2016-01-01

    The high incidence of hybridization in waterfowl (ducks, geese and swans) makes this bird group an excellent study system to answer questions related to the evolution and maintenance of species boundaries. However, knowledge on waterfowl hybridization is biased towards ducks, with a large knowledge gap in geese. In this review, we assemble the available information on hybrid geese by focusing on three main themes: (1) incidence and frequency, (2) behavioural mechanisms leading to hybridizatio...

  14. Hybrid solar lighting distribution systems and components

    Science.gov (United States)

    Muhs, Jeffrey D.; Earl, Dennis D.; Beshears, David L.; Maxey, Lonnie C.; Jordan, John K.; Lind, Randall F.

    2011-07-05

    A hybrid solar lighting distribution system and components having at least one hybrid solar concentrator, at least one fiber receiver, at least one hybrid luminaire, and a light distribution system operably connected to each hybrid solar concentrator and each hybrid luminaire. A controller operates all components.

  15. Hybrid solar lighting systems and components

    Science.gov (United States)

    Muhs, Jeffrey D.; Earl, Dennis D.; Beshears, David L.; Maxey, Lonnie C.; Jordan, John K.; Lind, Randall F.

    2007-06-12

    A hybrid solar lighting system and components having at least one hybrid solar concentrator, at least one fiber receiver, at least one hybrid luminaire, and a light distribution system operably connected to each hybrid solar concentrator and each hybrid luminaire. A controller operates each component.

  16. The governance of hybrid organisations

    DEFF Research Database (Denmark)

    Spear, Roger; Cornforth, Chris

    2010-01-01

    The focus of this chapter is on the governance of third sector organizations (TSOs) and the challenges that are raised by hybridity. In particular it will focus on the question how does hybridity affect governance structures and processes and the challenges that governing bodies face?......The focus of this chapter is on the governance of third sector organizations (TSOs) and the challenges that are raised by hybridity. In particular it will focus on the question how does hybridity affect governance structures and processes and the challenges that governing bodies face?...

  17. Efficacy of topical 10% urea-based lotion in patients with ichthyosis vulgaris: a two-center, randomized, controlled, single-blind, right-vs.-left study in comparison with standard glycerol-based emollient cream.

    Science.gov (United States)

    Tadini, Gianluca; Giustini, Sandra; Milani, Massimo

    2011-12-01

    Ichthyoses are genetic disorders of keratinization which are uncomfortable due to their conspicuous scaling, itching and cosmetic problems. Ichthyoses can lead to social discrimination and psychological problems. Ichthyosis vulgaris (IV) is the most common form of these geno-dermatoses. IV is a chronic disorder that often requires continuous therapy. Emollient and keratolytic products are the mainstay treatments of IV. It is important that efficient, safe and well tolerated therapies should be available. Direct comparative data regarding efficacy of different emollient products in IV patients are very few. The aim of the study was to investigate the keratolytic and moisturizing properties as well as the tolerance of a new urea topical formulation (Ureadin Rx10) when applied to hyperkeratotic and dry skin in patients with (IV) in comparison with a standard emollient cream. The study was conducted as a two-center, randomized, controlled, single-blind, intra-patient (right-vs.-left) trial design. A total of 30 patients with IV between 8 and 65 (mean age: 25 years) treated with a 10% urea-based lotion, Ureadin Rx 10 * *Ureadin RX 10 is a registered trade name of ISDIN, Spain. (URx), for 4 weeks or a glycerol-based emollient cream, Dexeryl † †Dexeryl is a registered trade name of Pierre Fabre Dermatologie. (DC), in a right-vs.-left study design. Primary outcome was a 5-point SRRC Index score (evaluating scaling roughness, redness and cracks) evaluated at baseline and after 2 and 4 weeks of treatment. As secondary endpoints patients evaluated also the global efficacy (GE) and global tolerability (GT) scores with the help of a 10 cm visual analogue scale (0 = no efficacy at all/very bad tolerability; 10: excellent efficacy/excellent tolerability). At baseline the mean (SD) SRRC score was 9.5 (1.9) in the URx treated sites and 9.5 (1.9) in the DC treated sites. A total of 27 patients (90%) concluded the study period. Three patients were withdrawn prematurely

  18. Cryogenic Hybrid Magnetic Bearing

    Science.gov (United States)

    Meeks, Crawford R.; Dirusso, Eliseo; Brown, Gerald V.

    1994-01-01

    Cryogenic hybrid magnetic bearing is example of class of magnetic bearings in which permanent magnets and electromagnets used to suspend shafts. Electromagnets provide active control of position of shaft. Bearing operates at temperatures from -320 degrees F (-196 degrees C) to 650 degrees F (343 degrees C); designed for possible use in rocket-engine turbopumps, where effects of cryogenic environment and fluid severely limit lubrication of conventional ball bearings. This and similar bearings also suitable for terrestrial rotating machinery; for example, gas-turbine engines, high-vacuum pumps, canned pumps, precise gimbals that suspend sensors, and pumps that handle corrosive or gritty fluids.

  19. Hybrid power semiconductor

    Science.gov (United States)

    Chen, D. Y.

    1985-10-01

    The voltage rating of a bipolar transistor may be greatly extended while at the same time reducing its switching time by operating it in conjunction with FETs in a hybrid circuit. One FET is used to drive the bipolar transistor while the other FET is connected in series with the transistor and an inductive load. Both FETs are turned on or off by a single drive signal of load power, the second FET upon ceasing conductions, rendering one power electrode of the bipolar transistor open. Means are provided to dissipate currents which flow after the bipolar transistor is rendered nonconducting.

  20. Hybrid Random Fields

    CERN Document Server

    Freno, Antonino

    2011-01-01

    This book presents an exciting new synthesis of directed and undirected, discrete and continuous graphical models. Combining elements of Bayesian networks and Markov random fields, the newly introduced hybrid random fields are an interesting approach to get the best of both these worlds, with an added promise of modularity and scalability. The authors have written an enjoyable book---rigorous in the treatment of the mathematical background, but also enlivened by interesting and original historical and philosophical perspectives. -- Manfred Jaeger, Aalborg Universitet The book not only marks an

  1. Reflections on Intellectual Hybridity

    Directory of Open Access Journals (Sweden)

    Kimala Price

    2012-05-01

    Full Text Available Drawing from the growing literature on interdisciplinarity and my own experiences as an intellectual hybrid, I discuss the personal and institutional challenges inherent in crossing disciplinary boundaries in the academy. I argue that boundary crossing is a natural occurrence and that the issue of (interdisciplinarity is a matter of degree and of determining who gets to define the boundaries. Defining boundaries is not merely an intellectual enterprise, but also a political act that delineates what is, or is not, legitimate scholarship. This issue is especially salient to women's and gender studies during times of economic distress and educational budget cuts.

  2. Hybrid Keyword Search Auctions

    OpenAIRE

    Goel, Ashish; Munagala, Kamesh

    2008-01-01

    Search auctions have become a dominant source of revenue generation on the Internet. Such auctions have typically used per-click bidding and pricing. We propose the use of hybrid auctions where an advertiser can make a per-impression as well as a per-click bid, and the auctioneer then chooses one of the two as the pricing mechanism. We assume that the advertiser and the auctioneer both have separate beliefs (called priors) on the click-probability of an advertisement. We first prove that the ...

  3. Hybrid optofluidic biosensors

    Science.gov (United States)

    Parks, Joshua W.

    Optofluidics, born of the desire to create a system containing microfluidic environments with integrated optical elements, has seen dramatic increases in popularity over the last 10 years. In particular, the application of this technology towards chip based molecular sensors has undergone significant development. The most sensitive of these biosensors interface liquid- and solid-core antiresonant reflecting optical waveguides (ARROWs). These sensor chips are created using conventional silicon microfabrication. As such, ARROW technology has previously been unable to utilize state-of-the-art microfluidic developments because the technology used--soft polydimethyl siloxane (PDMS) micromolded chips--is unamenable to the silicon microfabrication workflows implemented in the creation of ARROW detection chips. The original goal of this thesis was to employ hybrid integration, or the connection of independently designed and fabricated optofluidic and microfluidic chips, to create enhanced biosensors with the capability of processing and detecting biological samples on a single hybrid system. After successful demonstration of this paradigm, this work expanded into a new direction--direct integration of sensing and detection technologies on a new platform with dynamic, multi-dimensional photonic re-configurability. This thesis reports a number of firsts, including: • 1,000 fold optical transmission enhancement of ARROW optofluidic detection chips through thermal annealing, • Detection of single nucleic acids on a silicon-based ARROW chip, • Hybrid optofluidic integration of ARROW detection chips and passive PDMS microfluidic chips, • Hybrid optofluidic integration of ARROW detection chips and actively controllable PDMS microfluidic chips with integrated microvalves, • On-chip concentration and detection of clinical Ebola nucleic acids, • Multimode interference (MMI) waveguide based wavelength division multiplexing for detection of single influenza virions,

  4. Hybrid vehicle potential assessment. Volume 7. Hybrid vehicle review

    Energy Technology Data Exchange (ETDEWEB)

    Leschly, K.O.

    1979-09-30

    Review of hybrid vehicles (HVs) built during the past ten years or planned to be built in the near future is presented. An attempt is made to classify and analyze these vehicles to get an overall picture of their key characteristics. The review includes on-road hybrid passenger cars, trucks, vans, and buses.

  5. Hybrid vehicle potential assessment. Volume 7: Hybrid vehicle review

    Science.gov (United States)

    Leschly, K. O.

    1979-01-01

    Review of hybrid vehicles built during the past ten years or planned to be built in the near future is presented. An attempt is made to classify and analyze these vehicles to get an overall picture of their key characteristics. The review includes onroad hybrid passenger cars, trucks, vans, and buses.

  6. The Hybrid Advantage: Graduate Student Perspectives of Hybrid Education Courses

    Science.gov (United States)

    Hall, Sarah; Villareal, Donna

    2015-01-01

    Hybrid courses combine online and face-to-face learning environments. To organize and teach hybrid courses, instructors must understand the uses of multiple online learning tools and face-toface classroom activities to promote and monitor the progress of students. The purpose of this phenomenological study was to explore the perspectives of…

  7. Analysis of hybrid viscous damper by real time hybrid simulations

    DEFF Research Database (Denmark)

    Brodersen, Mark Laier; Ou, Ge; Høgsberg, Jan Becker

    2016-01-01

    Results from real time hybrid simulations are compared to full numerical simulations for a hybrid viscous damper, composed of a viscous dashpot in series with an active actuator and a load cell. By controlling the actuator displacement via filtered integral force feedback the damping performance...... of the hybrid viscous damper is improved, while for pure integral force feedback the damper stroke is instead increased. In the real time hybrid simulations viscous damping is emulated by a bang-bang controlled Magneto-Rheological (MR) damper. The controller activates high-frequency modes and generates drift...... in the actuator displacement, and only a fraction of the measured damper force can therefore be used as input to the investigated integral force feedback in the real time hybrid simulations....

  8. Arabidopsis hybrid speciation processes.

    Science.gov (United States)

    Schmickl, Roswitha; Koch, Marcus A

    2011-08-23

    The genus Arabidopsis provides a unique opportunity to study fundamental biological questions in plant sciences using the diploid model species Arabidopsis thaliana and Arabidopsis lyrata. However, only a few studies have focused on introgression and hybrid speciation in Arabidopsis, although polyploidy is a common phenomenon within this genus. More recently, there is growing evidence of significant gene flow between the various Arabidopsis species. So far, we know Arabidopsis suecica and Arabidopsis kamchatica as fully stabilized allopolyploid species. Both species evolved during Pleistocene glaciation and deglaciation cycles in Fennoscandinavia and the amphi-Beringian region, respectively. These hybrid studies were conducted either on a phylogeographic scale or reconstructed experimentally in the laboratory. In our study we focus at a regional and population level. Our research area is located in the foothills of the eastern Austrian Alps, where two Arabidopsis species, Arabidopsis arenosa and A. lyrata ssp. petraea, are sympatrically distributed. Our hypothesis of genetic introgression, migration, and adaptation to the changing environment during the Pleistocene has been confirmed: We observed significant, mainly unidirectional gene flow between the two species, which has given rise to the tetraploid A. lyrata. This cytotype was able to escape from the narrow ecological niche occupied by diploid A. lyrata ssp. petraea on limestone outcrops by migrating northward into siliceous areas, leaving behind a trail of genetic differentiation.

  9. Suppression subtractive hybridization.

    Science.gov (United States)

    Ghorbel, Mohamed T; Murphy, David

    2011-01-01

    Comparing two RNA populations that differ from the effects of a single independent variable, such as a drug treatment or a specific genetic defect, can establish differences in the abundance of specific transcripts that vary in a population dependent manner. There are different methods for identifying differentially expressed genes. These methods include microarray, Serial Analysis of Gene Expression (SAGE), and quantitative Reverse-Transcriptase Polymerase Chain Reaction (qRT-PCR). Herein, the protocol describes an easy and cost-effective alternative that does not require prior knowledge of the transcriptomes under examination. It is specifically relevant when low levels of RNA starting material are available. This protocol describes the use of Switching Mechanism At RNA Termini Polymerase Chain Reaction (SMART-PCR) to amplify cDNA from small amounts of RNA. The amplified cDNA populations under comparison are then subjected to Suppression Subtractive Hybridization (SSH-PCR). SSH-PCR is a technique that couples subtractive hybridization with suppression PCR to selectively amplify fragments of differentially expressed genes. The resulting products are cDNA populations enriched for significantly overrepresented transcripts in either of the two input RNAs. These cDNA populations can then be cloned to generate subtracted cDNA library. Microarrays made with clones from the subtracted forward and reverse cDNA libraries are then screened for differentially expressed genes using targets generated from tester and driver total RNAs.

  10. Landmarks in Hybrid Planning

    Directory of Open Access Journals (Sweden)

    Mohamed Elkawkagy

    2013-11-01

    Full Text Available Although planning techniques achieved a significant progress during recent years, solving many planning problem still difficult even for modern planners. In this paper, we will adopt landmark concept to hybrid planning setting - a method that combines reasoning about procedural knowledge and causalities. Land-marks are a well-known concept in the realm of classical planning. Recently, they have been adapted to hierarchical approaches. Such landmarks can be extracted in a pre-processing step from a declarative hierarchical planning domain and problem description. It was shown how this technique allows for a considerable reduction of the search space by eliminating futile plan development options before the actual planning. Therefore, we will present a new approach to in¬tegrate landmark pre-processing technique in the context of hierarchical planning with landmark technique in the classical planning. This integration allows to incorporate the ability of using extracted landmark tasks from hierarchical domain knowledge in the form of HTN and using landmark literals from classical planning. To this end, we will construct a transformation technique to transform the hybrid planning domain into a classical domain model. The method¬ologies in this paper have been implemented successfully, and we will present some experimental results that give evidence for the consid-erable performance increase gained through planning system.

  11. Overview on hybrid propulsion

    Science.gov (United States)

    Calabro, M.

    2011-10-01

    Aside of research works, this historical survey shows propulsion units used by students for small satellites and for gas generation, or those for the Space Ship One, even if LOx/HTPB was studied and tested in large motors for its potential very low cost; however, this combination highlights a series of technical problems without any performance advantage over the existing LOx/Kerosene family and never been operational for ETO applications. The particularity of hybrid propulsion is to use the state-of-the-art of both liquids and solids; the only show stopper is the propellant itself. The past work focused on LOx/HTPB (selected for its low cost) appears to be a dead-end (combustion problems and global low performances resulting from a high level of residuals). The solution that appears through the past experience is the addition of hydrides to a binder (HTPB or other) or to a binder and a homogeneous fuel or a mixture of both, with or without others additives; within these solutions some will not present any manufacturing problem and some may have a low cost. Nevertheless, the studies of the following phases have to demonstrate the compatibility of the potential regression rate range with a high-performance global design of a hybrid Motor and the manufacturing at a reasonable cost of a hydride giving a high level of performances.

  12. Hybrid Turbine Electric Vehicle

    Science.gov (United States)

    Viterna, Larry A.

    1997-01-01

    Hybrid electric power trains may revolutionize today's ground passenger vehicles by significantly improving fuel economy and decreasing emissions. The NASA Lewis Research Center is working with industry, universities, and Government to develop and demonstrate a hybrid electric vehicle. Our partners include Bowling Green State University, the Cleveland Regional Transit Authority, Lincoln Electric Motor Division, the State of Ohio's Department of Development, and Teledyne Ryan Aeronautical. The vehicle will be a heavy class urban transit bus offering double the fuel economy of today's buses and emissions that are reduced to 1/10th of the Environmental Protection Agency's standards. At the heart of the vehicle's drive train is a natural-gas-fueled engine. Initially, a small automotive engine will be tested as a baseline. This will be followed by the introduction of an advanced gas turbine developed from an aircraft jet engine. The engine turns a high-speed generator, producing electricity. Power from both the generator and an onboard energy storage system is then provided to a variable-speed electric motor attached to the rear drive axle. An intelligent power-control system determines the most efficient operation of the engine and energy storage system.

  13. Hybrid internet access

    Science.gov (United States)

    Arora, Vivek; Baras, John S.; Dillon, Douglas; Falk, Aaron; Suphasindhu, Narin

    1995-01-01

    Access to the Internet is either too slow (dial-up SLIP) or too expensive (switched 56 kbps, frame relay) for the home user or small enterprise. The Center for Satellite and Hybrid Communication Networks and Hughes Network Systems have collaborated using systems integration principles to develop a prototype of a low-cost hybrid (dial-up and satellite) newtork terminal which can deliver data from the Internet to the user at rates up to 160 kbps. An asymmetric TCP/IP connection is used breaking the network link into two physical channels: a terrestrial dial-up for carrying data from the terminal into the Internet and a receive-only satellite link carrying IP packets from the Internet to the user. With a goal of supporting bandwidth hungry Internet applications such as Mosaic, Gopher, and FTP, this system has been designed to support any Intel 80386/486 PC, any commercial TCP/IP package, any unmodified host on the Internet, and any of the routers, etc., within the Internet. The design exploits the following three observations: 1) satellites are able to offer high bandwidth connections to a large geographical area, 2) a receive-only VSAT is cheap to manufacture and easier to install than one which can also transmit, and 3) most computer users, especially those in a home environment, will want to consume much more information than they generate. IP encapsulation, or tunneling, issued to manipulate the TCP/IP protocols to route packets asymmetrically.

  14. Unified Hybrid Network Theoretical Model Trilogy

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The first of the unified hybrid network theoretical model trilogy (UHNTF) is the harmonious unification hybrid preferential model (HUHPM), seen in the inner loop of Fig. 1, the unified hybrid ratio is defined.

  15. Chaotic Dynamics in Hybrid Systems

    NARCIS (Netherlands)

    P.J. Collins (Pieter)

    2008-01-01

    htmlabstractIn this paper we give an overview of some aspects of chaotic dynamics in hybrid systems, which comprise different types of behaviour. Hybrid systems may exhibit discontinuous dependence on initial conditions leading to new dynamical phenomena. We indicate how methods from topological

  16. Chaotic dynamics in hybrid systems

    NARCIS (Netherlands)

    P.J. Collins (Pieter)

    2008-01-01

    htmlabstractIn this paper we give an overview of some aspects of chaotic dynamics in hybrid systems, which comprise different types of behaviour. Hybrid systems may exhibit discontinuous dependence on initial conditions leading to new dynamical phenomena. We indicate how methods from topological

  17. The governance of hybrid organisations

    DEFF Research Database (Denmark)

    Spear, Roger; Cornforth, Chris

    2010-01-01

    The focus of this chapter is on the governance of third sector organizations (TSOs) and the challenges that are raised by hybridity. In particular it will focus on the question how does hybridity affect governance structures and processes and the challenges that governing bodies face?...

  18. Expanding Discourse Repertoires with Hybridity

    Science.gov (United States)

    Kelly, Gregory J.

    2012-01-01

    In "Hybrid discourse practice and science learning" Kamberelis and Wehunt present a theoretically rich argument about the potential of hybrid discourses for science learning. These discourses draw from different forms of "talk, social practice, and material practices" to create interactions that are "intertextually complex" and "interactionally…

  19. Design Principles for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system -Hybrid Ventilation....... The hybrid ventilation concepts, design challenges and - principles are discussed and illustrated by four building examples....

  20. Hybridity in Embedded Computing Systems

    Institute of Scientific and Technical Information of China (English)

    虞慧群; 孙永强

    1996-01-01

    An embedded system is a system that computer is used as a component in a larger device.In this paper,we study hybridity in embedded systems and present an interval based temporal logic to express and reason about hybrid properties of such kind of systems.

  1. Electric/Hybrid Vehicle Simulation

    Science.gov (United States)

    Slusser, R. A.; Chapman, C. P.; Brennand, J. P.

    1985-01-01

    ELVEC computer program provides vehicle designer with simulation tool for detailed studies of electric and hybrid vehicle performance and cost. ELVEC simulates performance of user-specified electric or hybrid vehicle under user specified driving schedule profile or operating schedule. ELVEC performs vehicle design and life cycle cost analysis.

  2. Hybrid Charmonium from Lattice QCD

    CERN Document Server

    Luo, X Q

    2006-01-01

    We review our recent results on the JPC = 0¡¡ exotic hybrid charmonium mass and JPC = 0¡+, 1¡¡ and 1++ nonexotic hybrid charmonium spectrum from anisotropic improved lattice QCD and discuss the relevance to the recent discovery of the Y(4260) state and future experimental search for other states.

  3. Hybrid spread spectrum radio system

    Science.gov (United States)

    Smith, Stephen F [London, TN; Dress, William B [Camas, WA

    2010-02-09

    Systems and methods are described for hybrid spread spectrum radio systems. A method, includes receiving a hybrid spread spectrum signal including: fast frequency hopping demodulating and direct sequence demodulating a direct sequence spread spectrum signal, wherein multiple frequency hops occur within a single data-bit time and each bit is represented by chip transmissions at multiple frequencies.

  4. Hybrid laser-arc welding

    DEFF Research Database (Denmark)

    Hybrid laser-arc welding (HLAW) is a combination of laser welding with arc welding that overcomes many of the shortfalls of both processes. This important book gives a comprehensive account of hybrid laser-arc welding technology and applications. The first part of the book reviews...... the characteristics of the process, including the properties of joints produced by hybrid laser-arc welding and ways of assessing weld quality. Part II discusses applications of the process to such metals as magnesium alloys, aluminium and steel as well as the use of hybrid laser-arc welding in such sectors as ship...... building and the automotive industry. With its distinguished editor and international team of contributors, Hybrid laser-arc welding, will be a valuable source of reference for all those using this important welding technology. Professor Flemming Ove Olsen works in the Department of Manufacturing...

  5. Detecting hybridization using ancient DNA.

    Science.gov (United States)

    Schaefer, Nathan K; Shapiro, Beth; Green, Richard E

    2016-06-01

    It is well established that related species hybridize and that this can have varied but significant effects on speciation and environmental adaptation. It should therefore come as no surprise that hybridization is not limited to species that are alive today. In the last several decades, advances in technologies for recovering and sequencing DNA from fossil remains have enabled the assembly of high-coverage genome sequences for a growing diversity of organisms, including many that are extinct. Thanks to the development of new statistical approaches for detecting and quantifying admixture from genomic data, genomes from extinct populations have proven useful both in revealing previously unknown hybridization events and informing the study of hybridization between living organisms. Here, we review some of the key recent statistical innovations for detecting ancient hybridization using genomewide sequence data and discuss how these innovations have revised our understanding of human evolutionary history.

  6. Variables Affecting Two Electron Transport System Assays

    OpenAIRE

    Burton, G. Allen; Lanza, Guy R.

    1986-01-01

    Several methodological variables were critical in two commonly used electron transport activity assays. The dehydrogenase assay based on triphenyl formazan production exhibited a nonlinear relationship between formazan production (dehydrogenase activity) and sediment dilution, and linear formazan production occurred for 1 h in sediment slurries. Activity decreased with increased time of sediment storage at 4°C. Extraction efficiencies of formazan from sediment varied with alcohol type; methan...

  7. Molecular evidence for hybridization in Colias (Lepidoptera: Pieridae): are Colias hybrids really hybrids?

    Science.gov (United States)

    Dwyer, Heather E; Jasieniuk, Marie; Okada, Miki; Shapiro, Arthur M

    2015-01-01

    Gene flow and hybridization among species dramatically affect our understanding of the species as a biological unit, species relationships, and species adaptations. In North American Colias eurytheme and Colias eriphyle, there has been historical debate over the extent of hybridization occurring and the identity of phenotypically intermediate individuals as genetic hybrids. This study assesses the population structure of these two species to measure the extent of hybridization and the genetic identity of phenotypic intermediates as hybrids. Amplified fragment length polymorphism (AFLP) marker analysis was performed on 378 specimens collected from northern California and Nevada. Population structure was inferred using a Bayesian/Markov chain Monte Carlo method, which probabilistically assigns individuals to genetic clusters. Three genetic clusters provided the best fit for the data. C. eurytheme individuals were primarily assigned to two closely related clusters, and C. eriphyle individuals were mostly assigned to a third, more distantly related cluster. There appeared to be significant hybridization between the two species. Individuals of intermediate phenotype (putative hybrids) were found to be genetically indistinguishable from C. eriphyle, indicating that previous work based on the assumption that these intermediate forms are hybrids may warrant reconsideration. PMID:26306172

  8. Hybrid Natural Inflation

    Science.gov (United States)

    Ross, Graham G.; Germán, Gabriel; Vázquez, J. Alberto

    2016-05-01

    We construct two simple effective field theory versions of Hybrid Natural Inflation (HNI) that illustrate the range of its phenomenological implications. The resulting inflationary sector potential, V = Δ4(1 + acos( ϕ/f)), arises naturally, with the inflaton field a pseudo-Nambu-Goldstone boson. The end of inflation is triggered by a waterfall field and the conditions for this to happen are determined. Also of interest is the fact that the slow-roll parameter ɛ (and hence the tensor r) is a non-monotonic function of the field with a maximum where observables take universal values that determines the maximum possible tensor to scalar ratio r. In one of the models the inflationary scale can be as low as the electroweak scale. We explore in detail the associated HNI phenomenology, taking account of the constraints from Black Hole production, and perform a detailed fit to the Planck 2015 temperature and polarisation data.

  9. Auditing Hybrid IT Environments

    Directory of Open Access Journals (Sweden)

    Georgiana Mateescu

    2014-01-01

    Full Text Available This paper presents a personal approach of auditing the hybrid IT environments consisting in both on premise and on demand services and systems. The analysis is performed from both safety and profitability perspectives and it aims to offer to strategy, technical and business teams a representation of the value added by the cloud programme within the company’s portfolio. Starting from the importance of the IT Governance in the actual business environments, we presented in the first section the main principles that drive the technology strategy in order to maximize the value added by IT assets in the business products. Section two summarizes the frameworks leveraged by our approach in order to implement the safety and profitability computation algorithms described in the third section. The paper concludes with benefits of our personal frameworks and presents the future developments.

  10. Hybrid Noncoherent Network Coding

    CERN Document Server

    Skachek, Vitaly; Nedic, Angelia

    2011-01-01

    We describe a novel extension of subspace codes for noncoherent networks, suitable for use when the network is viewed as a communication system that introduces both dimension and symbol errors. We show that when symbol erasures occur in a significantly large number of different basis vectors transmitted through the network and when the min-cut of the networks is much smaller then the length of the transmitted codewords, the new family of codes outperforms their subspace code counterparts. For the proposed coding scheme, termed hybrid network coding, we derive two upper bounds on the size of the codes. These bounds represent a variation of the Singleton and of the sphere-packing bound. We show that a simple concatenated scheme that represents a combination of subspace codes and Reed-Solomon codes is asymptotically optimal with respect to the Singleton bound. Finally, we describe two efficient decoding algorithms for concatenated subspace codes that in certain cases have smaller complexity than subspace decoder...

  11. Nanoporous hybrid electrolytes

    KAUST Repository

    Schaefer, Jennifer L.

    2011-01-01

    Oligomer-suspended SiO2-polyethylene glycol nanoparticles are studied as porous media electrolytes. At SiO2 volume fractions, , bracketing a critical value y ≈ 0.29, the suspensions jam and their mechanical modulus increase by more than seven orders. For >y, the mean pore diameter is close to the anion size, yet the ionic conductivity remains surprisingly high and can be understood, at all , using a simple effective medium model proposed by Maxwell. SiO 2-polyethylene glycol hybrid electrolytes are also reported to manifest attractive electrochemical stability windows (0.3-6.3 V) and to reach a steady-state interfacial impedance when in contact with metallic lithium. © 2010 The Royal Society of Chemistry.

  12. Hybrid vehicle control

    Energy Technology Data Exchange (ETDEWEB)

    Shallvari, Iva; Velnati, Sashidhar; DeGroot, Kenneth P.

    2015-07-28

    A method and apparatus for heating a catalytic converter's catalyst to an efficient operating temperature in a hybrid electric vehicle when the vehicle is in a charge limited mode such as e.g., the charge depleting mode or when the vehicle's high voltage battery is otherwise charge limited. The method and apparatus determine whether a high voltage battery of the vehicle is incapable of accepting a first amount of charge associated with a first procedure to warm-up the catalyst. If it is determined that the high voltage battery is incapable of accepting the first amount of charge, a second procedure with an acceptable amount of charge is performed to warm-up the catalyst.

  13. Hybrid vehicle control

    Science.gov (United States)

    Shallvari, Iva; Velnati, Sashidhar; DeGroot, Kenneth P.

    2015-07-28

    A method and apparatus for heating a catalytic converter's catalyst to an efficient operating temperature in a hybrid electric vehicle when the vehicle is in a charge limited mode such as e.g., the charge depleting mode or when the vehicle's high voltage battery is otherwise charge limited. The method and apparatus determine whether a high voltage battery of the vehicle is incapable of accepting a first amount of charge associated with a first procedure to warm-up the catalyst. If it is determined that the high voltage battery is incapable of accepting the first amount of charge, a second procedure with an acceptable amount of charge is performed to warm-up the catalyst.

  14. Hybrid Batch Bayesian Optimization

    CERN Document Server

    Azimi, Javad; Fern, Xiaoli

    2012-01-01

    Bayesian Optimization aims at optimizing an unknown non-convex/concave function that is costly to evaluate. We are interested in application scenarios where concurrent function evaluations are possible. Under such a setting, BO could choose to either sequentially evaluate the function, one input at a time and wait for the output of the function before making the next selection, or evaluate the function at a batch of multiple inputs at once. These two different settings are commonly referred to as the sequential and batch settings of Bayesian Optimization. In general, the sequential setting leads to better optimization performance as each function evaluation is selected with more information, whereas the batch setting has an advantage in terms of the total experimental time (the number of iterations). In this work, our goal is to combine the strength of both settings. Specifically, we systematically analyze Bayesian optimization using Gaussian process as the posterior estimator and provide a hybrid algorithm t...

  15. Photochromic mesoporous hybrid coatings

    Science.gov (United States)

    Raboin, L.; Matheron, M.; Gacoin, T.; Boilot, J.-P.

    2008-09-01

    Spirooxazine (SO) photochromic molecules were trapped in sol-gel matrices. In order to increase the colourability and improve mechanical properties of sol-gel photochromic films, we present an original strategy in which SO photochromic molecules were dispersed in mesoporous organized films using the impregnation technique. Well-ordered organosilicate mesoporous coatings with the 3D-hexagonal symmetry were prepared by the sol-gel technique. These robust mesoporous films, which contain high amounts of hydrophobic methyl groups at the pore surface, offer optimized environments for photochromic dyes dispersed by impregnation technique. After impregnation by a spirooxazine solution, the photochromic response is only slightly slower when compared with mesostructured or soft sol-gel matrices, showing that mesoporous organized hybrid matrix are good host for photochromic dyes. Moreover, the molecular loading in films is easily adjustable in a large range using multi-impregnation procedure and increasing the film thickness leading to coatings for optical switching devices.

  16. Hybrid Heat Exchangers

    Science.gov (United States)

    Tu, Jianping Gene; Shih, Wei

    2010-01-01

    A hybrid light-weight heat exchanger concept has been developed that uses high-conductivity carbon-carbon (C-C) composites as the heat-transfer fins and uses conventional high-temperature metals, such as Inconel, nickel, and titanium as the parting sheets to meet leakage and structural requirements. In order to maximize thermal conductivity, the majority of carbon fiber is aligned in the fin direction resulting in 300 W/m.K or higher conductivity in the fin directions. As a result of this fiber orientation, the coefficient of thermal expansion (CTE) of the C-C composite in both non-fiber directions matches well with the CTE of various high-temperature metal alloys. This allows the joining of fins and parting sheets by using high-temperature braze alloys.

  17. From hybrid-media system to hybrid-media politicians

    DEFF Research Database (Denmark)

    Eberholst, Mads Kæmsgaard; Ørsten, Mark; Burkal, Rasmus

    2017-01-01

    An increasingly complex hybrid system of social- and traditional-news media surrounds Nordic election campaigns as politically experienced incumbents favour traditional news media, and younger, lesser-known candidates’ social media. Despite little evidence for hybrid-media politicians, politicians......’ media use is changing rapidly; 15%–16% of Danish candidates used Twitter in 2011 but 68% in 2015. In this large-sample content analysis, party leaders have high traditional-news-media and low Twitter presence, and younger candidates visa-versa, but some politicians have high presence in both. Hybrid...

  18. Hybrid Filter Membrane

    Science.gov (United States)

    Laicer, Castro; Rasimick, Brian; Green, Zachary

    2012-01-01

    Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

  19. Wankel engine for hybrid powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Butti, A. [Univ. of Florence (Italy); Site, V.D.

    1995-12-31

    The Wankel engine is suited to be used to drive hybrid propulsion systems. The main disadvantage of hybrid propulsion systems is the complexity that causes a high weight and large dimensions. For these reason hybrid systems are more suitable for large size vehicle (buses, vans) rather than for small passenger cars. A considerable reduction of hybrid systems weight and dimensions can be obtained using a Wankel rotary engine instead of a conventional engine. The Wankel engine is light, compact, simple, and produces low noise and low vibrations. Therefore a Wankel engine powered hybrid system is suited to be used on small cars. In this paper a 1,000 kg parallel hybrid car with continuously variable transmission and a 6,000 kg series hybrid minibus both equipped with Wankel engines are considered. The Wankel engine works at steady state to minimize fuel consumption and exhaust emissions. The simulation of the behavior of these two vehicles during a ECE + EUDC test cycle is presented in order to evaluate the performances of the systems.

  20. Fabrication of Hybrid Petroelectric Vehicle

    Directory of Open Access Journals (Sweden)

    G. Adinarayana

    2014-10-01

    Full Text Available In automobile sector, the need for alternative fuel as a replacement of conventional fossil fuel, due to its depletion and amount of emission has given way for new technologies like Fuel cells vehicles, Electric vehicles. Still a lot of advancement has to take place in these technologies for commercialization. The gap between the current fossil fuel technology and zero emission vehicles can be bridged by hybrid technology. Hybrid vehicles are those which can run on two or more powering sources/fuels. Feasibility of this technology is been proved in four wheelers and automobile giants like Toyota, Honda, and Hyundai have launched successful vehicles like Toyota prius, Honda insight etc. This technology maximizes the advantages of the two fuels and minimizes the disadvantages of the same. The best preferred hybrid pair is electric and fossil fuel. This increases the mileage of the vehicle twice the existing and also reduces the emission to half. At present, we like to explore the hybrid technology in the two wheeler sector and its feasibility on road. This paper deals with an attempt to make a hybrid with electric start and petrol run. Further a design of basic hybrid elements like motor, battery, and engine. As on today, hybrid products are one of the best solutions for all pollution hazards at a fairly nominal price. An investment within the means of a common man that guarantees a better environment to live in.

  1. Hybrid Vehicle Program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1984-06-01

    This report summarizes the activities on the Hybrid Vehicle Program. The program objectives and the vehicle specifications are reviewed. The Hybrid Vehicle has been designed so that maximum use can be made of existing production components with a minimum compromise to program goals. The program status as of the February 9-10 Hardware Test Review is presented, and discussions of the vehicle subsystem, the hybrid propulsion subsystem, the battery subsystem, and the test mule programs are included. Other program aspects included are quality assurance and support equipment. 16 references, 132 figures, 47 tables.

  2. Pseudovector mesons, hybrids and glueballs

    CERN Document Server

    Burakovsky, L; Burakovsky, Leonid; Page, Philip R.

    2000-01-01

    We consider glueball- (hybrid) meson mixing for the low-lying four pseudovector states. The h_1'(1380) decays dominantly to K*K with some presence in rho pi and omega eta. The newly observed h_1(1600) has a D- to S-wave width ratio to omega eta which does not enable differentiation between a conventional and hybrid meson interpretation. We predict the decay pattern of the isopartner conventional or hybrid meson b_1(1650). A notably narrow s sbar partner h_1'(1810) is predicted.

  3. Completeness in Hybrid Type Theory

    DEFF Research Database (Denmark)

    Areces, Carlos; Blackburn, Patrick Rowan; Huertas, Antonia;

    2014-01-01

    We show that basic hybridization (adding nominals and @ operators) makes it possible to give straightforward Henkin-style completeness proofs even when the modal logic being hybridized is higher-order. The key ideas are to add nominals as expressions of type t, and to extend to arbitrary types...... the way we interpret @i in propositional and first-order hybrid logic. This means: interpret @iαa , where αa is an expression of any type a , as an expression of type a that rigidly returns the value that αa receives at the i-world. The axiomatization and completeness proofs are generalizations of those...

  4. Hybrid codes: Methods and applications

    Energy Technology Data Exchange (ETDEWEB)

    Winske, D. (Los Alamos National Lab., NM (USA)); Omidi, N. (California Univ., San Diego, La Jolla, CA (USA))

    1991-01-01

    In this chapter we discuss hybrid'' algorithms used in the study of low frequency electromagnetic phenomena, where one or more ion species are treated kinetically via standard PIC methods used in particle codes and the electrons are treated as a single charge neutralizing massless fluid. Other types of hybrid models are possible, as discussed in Winske and Quest, but hybrid codes with particle ions and massless fluid electrons have become the most common for simulating space plasma physics phenomena in the last decade, as we discuss in this paper.

  5. Hybrid laser-arc welding

    DEFF Research Database (Denmark)

    the characteristics of the process, including the properties of joints produced by hybrid laser-arc welding and ways of assessing weld quality. Part II discusses applications of the process to such metals as magnesium alloys, aluminium and steel as well as the use of hybrid laser-arc welding in such sectors as ship...... building and the automotive industry. With its distinguished editor and international team of contributors, Hybrid laser-arc welding, will be a valuable source of reference for all those using this important welding technology. Professor Flemming Ove Olsen works in the Department of Manufacturing...

  6. HYBRIDIZATION AND CHAMELEONIC JOURNALISM

    Directory of Open Access Journals (Sweden)

    Adriana Schryver Kurtz

    2016-12-01

    Full Text Available O texto aborda a crescente hibridização entre o Jornalismo e demais formatos midiáticos como resultado natural de um processo que já está na própria raiz da comunicação enquanto atividade histórica. A lógica interna e as potencialidades estéticas e discursivas do fenômeno são analisadas a partir das convergências entre jornalismo e cinema. Para tanto, utiliza o falso documentário Zelig (1983, texto fílmico de Woody Allen, híbrido por natureza, postulado como um microcosmo rico em pistas e sugestões para refletir sobre a fusão entre conteúdos informativos e não informativos.   PALAVRAS-CHAVE: Hibridização; Jornalismo; Cinema; Zelig.       ABSTRACT The text discusses the growing hybridization between journalism and other media formats as a natural result of a process that is already in the very root of communication while historical activity. The internal logic and the aesthetic and discursive potential of the phenomenon are analyzed through the convergences between journalism and cinema. Therefore, uses the mockumentary Zelig (1983, filmic text of Woody Allen, hybrid by nature, postulated as a microcosm rich in clues and suggestions to reflect about the merger between informative and uninformative content.      KEYWORDS: Hybridization; Journalism; Cinema; Zelig.     RESUMEN El texto aborda la creciente hibridación entre el periodismo y otros formatos de medios como um resultado natural de un proceso que ya está en la raíz misma de la comunicación mientras actividad histórica. Se analizan la lógica interna y el potencial estético y discursivo del fenómeno a través de las convergencias entre el periodismo y el cine. Para ello, utiliza el falso documental Zelig (1983, texto fílmico de Woody Allen, híbrido en su naturaleza, postulado como un microcosmos rico en pistas y sugerencias para reflexionar sobre la fusión entre contenidos informativos y no informativos.      PALABRAS CLAVE: Hibridaci

  7. Advanced Hybrid Computer Systems. Software Technology.

    Science.gov (United States)

    This software technology final report evaluates advances made in Advanced Hybrid Computer System software technology . The report describes what...automatic patching software is available as well as which analog/hybrid programming languages would be most feasible for the Advanced Hybrid Computer...compiler software . The problem of how software would interface with the hybrid system is also presented.

  8. How common is homoploid hybrid speciation?

    Science.gov (United States)

    Schumer, Molly; Rosenthal, Gil G; Andolfatto, Peter

    2014-06-01

    Hybridization has long been considered a process that prevents divergence between species. In contrast to this historical view, an increasing number of empirical studies claim to show evidence for hybrid speciation without a ploidy change. However, the importance of hybridization as a route to speciation is poorly understood, and many claims have been made with insufficient evidence that hybridization played a role in the speciation process. We propose criteria to determine the strength of evidence for homoploid hybrid speciation. Based on an evaluation of the literature using this framework, we conclude that although hybridization appears to be common, evidence for an important role of hybridization in homoploid speciation is more circumscribed.

  9. Real and Hybrid Atomic Orbitals.

    Science.gov (United States)

    Cook, D. B.; Fowler, P. W.

    1981-01-01

    Demonstrates that the Schrodinger equation for the hydrogenlike atom separates in both spheroconal and prolate spheroidal coordinates and that these separations provide a sound theoretical basis for the real and hybrid atomic orbitals. (Author/SK)

  10. Hybrid-Vehicle Transmission System

    Science.gov (United States)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  11. Hybrid Fuel Cell Technology Overview

    Energy Technology Data Exchange (ETDEWEB)

    None available

    2001-05-31

    For the purpose of this STI product and unless otherwise stated, hybrid fuel cell systems are power generation systems in which a high temperature fuel cell is combined with another power generating technology. The resulting system exhibits a synergism in which the combination performs with an efficiency far greater than can be provided by either system alone. Hybrid fuel cell designs under development include fuel cell with gas turbine, fuel cell with reciprocating (piston) engine, and designs that combine different fuel cell technologies. Hybrid systems have been extensively analyzed and studied over the past five years by the Department of Energy (DOE), industry, and others. These efforts have revealed that this combination is capable of providing remarkably high efficiencies. This attribute, combined with an inherent low level of pollutant emission, suggests that hybrid systems are likely to serve as the next generation of advanced power generation systems.

  12. Hybrid models for complex fluids

    CERN Document Server

    Tronci, Cesare

    2010-01-01

    This paper formulates a new approach to complex fluid dynamics, which accounts for microscopic statistical effects in the micromotion. While the ordinary fluid variables (mass density and momentum) undergo usual dynamics, the order parameter field is replaced by a statistical distribution on the order parameter space. This distribution depends also on the point in physical space and its dynamics retains the usual fluid transport features while containing the statistical information on the order parameter space. This approach is based on a hybrid moment closure for Yang-Mills Vlasov plasmas, which replaces the usual cold-plasma assumption. After presenting the basic properties of the hybrid closure, such as momentum map features, singular solutions and Casimir invariants, the effect of Yang-Mills fields is considered and a direct application to ferromagnetic fluids is presented. Hybrid models are also formulated for complex fluids with symmetry breaking. For the special case of liquid crystals, a hybrid formul...

  13. Annular Hybrid Rocket Motor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Engineers at SpaceDev have conducted a preliminary design and analysis of a proprietary annular design concept for a hybrid motor. A U.S. Patent application has been...

  14. Design Procedure for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per; Tjelflaat, Per Olaf

    Mechanical and natural ventilation systems have developed separately during many years. The natural next step in this development is development of ventilation concepts that utilises and combines the best features from each system into a new type of ventilation system - Hybrid Ventilation....... Buildings with hybrid ventilation often include other sustainable technologies and an energy optimisation requires an integrated approach in the design of the building and its mechanical systems. Therefore, the hybrid ventilation design procedure differs from the design procedure for conventional HVAC....... The first ideas on a design procedure for hybrid ventilation is presented and the different types of design methods, that is needed in different phases of the design process, is discussed....

  15. Towards Modelling of Hybrid Systems

    DEFF Research Database (Denmark)

    Wisniewski, Rafal

    2006-01-01

    The article is an attempt to use methods of category theory and topology for analysis of hybrid systems. We use the notion of a directed topological space; it is a topological space together with a set of privileged paths. Dynamical systems are examples of directed topological spaces. A hybrid...... system consists of a number of dynamical systems that are glued together according to information encoded in the discrete part of the system. We develop a definition of a hybrid system as a functor from the category generated by a transition system to the category of directed topological spaces. Its...... directed homotopy colimit (geometric realization) is a single directed topological space. The behavior of hybrid systems can be then understood in terms of the behavior of dynamical systems through the directed homotopy colimit....

  16. Hybrid-Vehicle Transmission System

    Science.gov (United States)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  17. Hybrid Platforms, Tools, and Resources

    Science.gov (United States)

    Linder, Kathryn E.; Bruenjes, Linda S.; Smith, Sarah A.

    2017-01-01

    This chapter discusses common tools and resources for building a hybrid course in a higher education setting and provides recommendations for best practices in Learning Management Systems and Open Educational Resources.

  18. A hybrid base isolation system

    Energy Technology Data Exchange (ETDEWEB)

    Hart, G.C. [Univ. of California, Los Angeles, CA (United States); Lobo, R.F.; Srinivasan, M. [Hart Consultant Group, Santa Monica, CA (United States); Asher, J.W. [kpff Engineers, Santa Monica, CA (United States)

    1995-12-01

    This paper proposes a new analysis procedure for hybrid base isolation buildings when considering the displacement response of a base isolated building to wind loads. The system is considered hybrid because of the presence of viscous dampers in the building above the isolator level. The proposed analysis approach incorporates a detailed site specific wind study combined with a dynamic nonlinear analysis of the building response.

  19. Ion-atom hybrid systems

    CERN Document Server

    Willitsch, Stefan

    2014-01-01

    The study of interactions between simultaneously trapped cold ions and atoms has emerged as a new research direction in recent years. The development of ion-atom hybrid experiments has paved the way for investigating elastic, inelastic and reactive collisions between these species at very low temperatures, for exploring new cooling mechanisms of ions by atoms and for implementing new hybrid quantum systems. The present lecture reviews experimental methods, recent results and upcoming developments in this emerging field.

  20. Information component of hybrid war

    OpenAIRE

    Bohdanov, Aleksander

    2015-01-01

    A hybrid warfare in the three-dimensional coordinate system «Matter-Information-measure» is considering. In particular, the information component is highlighted and analyzed. The factors of preparation of information operations is defined, which are disclosed as an example of experience of volunteer group information warfare of Institute of special communication and information security of NTUU «KPI».Keywords: coordinate system «Matter-Information-Measure» hybrid warfare, information componen...

  1. Formal Description of Hybrid Systems

    DEFF Research Database (Denmark)

    Zhou, Chaochen; Ji, Wang; Ravn, Anders P.

    1996-01-01

    A language to describe hybrid systems, i.e. networks of communicating discrete and continuous processes, is proposed. A semantics of the language is given in Extended Duration Calculus, a real-time interval logic with a proof system that allows reasoning in mathematical analysis about continuous ...... processes to be embedded into the logic. The semantics thus provides a secure link to hybrid system models based on a general theory of dynamical systems....

  2. Hybrid particles and associated methods

    Science.gov (United States)

    Fox, Robert V; Rodriguez, Rene; Pak, Joshua J; Sun, Chivin

    2015-02-10

    Hybrid particles that comprise a coating surrounding a chalcopyrite material, the coating comprising a metal, a semiconductive material, or a polymer; a core comprising a chalcopyrite material and a shell comprising a functionalized chalcopyrite material, the shell enveloping the core; or a reaction product of a chalcopyrite material and at least one of a reagent, heat, and radiation. Methods of forming the hybrid particles are also disclosed.

  3. Hybrid cluster identification

    Science.gov (United States)

    Martín-Herrero, J.

    2004-10-01

    I present a hybrid method for the labelling of clusters in two-dimensional lattices, which combines the recursive approach with iterative scanning to reduce the stack size required by the pure recursive technique, while keeping its benefits: single pass and straightforward cluster characterization and percolation detection parallel to the labelling. While the capacity to hold the entire lattice in memory is usually regarded as the major constraint for the applicability of the recursive technique, the required stack size is the real limiting factor. Resorting to recursion only for the transverse direction greatly reduces the recursion depth and therefore the required stack. It also enhances the overall performance of the recursive technique, as is shown by results on a set of uniform random binary lattices and on a set of samples of the Ising model. I also show how this technique may replace the recursive technique in Wolff's cluster algorithm, decreasing the risk of stack overflow and increasing its speed, and the Hoshen-Kopelman algorithm in the Swendsen-Wang cluster algorithm, allowing effortless characterization during generation of the samples and increasing its speed.

  4. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

    Stanley J. Miller; Grant L. Schelkoph; Grant E. Dunham

    2000-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and recollection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hour parametric tests and 100-hour proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency.

  5. Hybrid superconductor magnet bearings

    Science.gov (United States)

    Chu, Wei-Kan

    1995-01-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  6. Hybrid manifold embedding.

    Science.gov (United States)

    Liu, Yang; Liu, Yan; Chan, Keith C C; Hua, Kien A

    2014-12-01

    In this brief, we present a novel supervised manifold learning framework dubbed hybrid manifold embedding (HyME). Unlike most of the existing supervised manifold learning algorithms that give linear explicit mapping functions, the HyME aims to provide a more general nonlinear explicit mapping function by performing a two-layer learning procedure. In the first layer, a new clustering strategy called geodesic clustering is proposed to divide the original data set into several subsets with minimum nonlinearity. In the second layer, a supervised dimensionality reduction scheme called locally conjugate discriminant projection is performed on each subset for maximizing the discriminant information and minimizing the dimension redundancy simultaneously in the reduced low-dimensional space. By integrating these two layers in a unified mapping function, a supervised manifold embedding framework is established to describe both global and local manifold structure as well as to preserve the discriminative ability in the learned subspace. Experiments on various data sets validate the effectiveness of the proposed method.

  7. Hybrid Power Management (HPM)

    Science.gov (United States)

    Eichenberg, Dennis J.

    2007-01-01

    The NASA Glenn Research Center s Avionics, Power and Communications Branch of the Engineering and Systems Division initiated the Hybrid Power Management (HPM) Program for the GRC Technology Transfer and Partnership Office. HPM is the innovative integration of diverse, state-of-the-art power devices in an optimal configuration for space and terrestrial applications. The appropriate application and control of the various power devices significantly improves overall system performance and efficiency. The advanced power devices include ultracapacitors and fuel cells. HPM has extremely wide potential. Applications include power generation, transportation systems, biotechnology systems, and space power systems. HPM has the potential to significantly alleviate global energy concerns, improve the environment, and stimulate the economy. One of the unique power devices being utilized by HPM for energy storage is the ultracapacitor. An ultracapacitor is an electrochemical energy storage device, which has extremely high volumetric capacitance energy due to high surface area electrodes, and very small electrode separation. Ultracapacitors are a reliable, long life, maintenance free, energy storage system. This flexible operating system can be applied to all power systems to significantly improve system efficiency, reliability, and performance. There are many existing and conceptual applications of HPM.

  8. Hybrid power source

    Science.gov (United States)

    Singh, Harmohan N.

    2012-06-05

    A hybrid power system is comprised of a high energy density element such as a fuel-cell and high power density elements such as a supercapacitor banks. A DC/DC converter electrically connected to the fuel cell and converting the energy level of the energy supplied by the fuel cell. A first switch is electrically connected to the DC/DC converter. First and second supercapacitors are electrically connected to the first switch and a second switch. A controller is connected to the first switch and the second switch, monitoring charge levels of the supercapacitors and controls the switching in response to the charge levels. A load is electrically connected to the second switch. The first switch connects the DC/DC converter to the first supercapacitor when the second switch connects the second supercapacitor to the load. The first switch connects the DC/DC converter to the second supercapacitor when the second switch connects the first supercapacitor to the load.

  9. Hybrid spacecraft attitude control system

    Directory of Open Access Journals (Sweden)

    Renuganth Varatharajoo

    2016-02-01

    Full Text Available The hybrid subsystem design could be an attractive approach for futurespacecraft to cope with their demands. The idea of combining theconventional Attitude Control System and the Electrical Power System ispresented in this article. The Combined Energy and Attitude ControlSystem (CEACS consisting of a double counter rotating flywheel assemblyis investigated for small satellites in this article. Another hybrid systemincorporating the conventional Attitude Control System into the ThermalControl System forming the Combined Attitude and Thermal ControlSystem (CATCS consisting of a "fluid wheel" and permanent magnets isalso investigated for small satellites herein. The governing equationsdescribing both these novel hybrid subsystems are presented and theironboard architectures are numerically tested. Both the investigated novelhybrid spacecraft subsystems comply with the reference missionrequirements.The hybrid subsystem design could be an attractive approach for futurespacecraft to cope with their demands. The idea of combining theconventional Attitude Control System and the Electrical Power System ispresented in this article. The Combined Energy and Attitude ControlSystem (CEACS consisting of a double counter rotating flywheel assemblyis investigated for small satellites in this article. Another hybrid systemincorporating the conventional Attitude Control System into the ThermalControl System forming the Combined Attitude and Thermal ControlSystem (CATCS consisting of a "fluid wheel" and permanent magnets isalso investigated for small satellites herein. The governing equationsdescribing both these novel hybrid subsystems are presented and theironboard architectures are numerically tested. Both the investigated novelhybrid spacecraft subsystems comply with the reference missionrequirements.

  10. Optimal control of hybrid vehicles

    CERN Document Server

    Jager, Bram; Kessels, John

    2013-01-01

    Optimal Control of Hybrid Vehicles provides a description of power train control for hybrid vehicles. The background, environmental motivation and control challenges associated with hybrid vehicles are introduced. The text includes mathematical models for all relevant components in the hybrid power train. The power split problem in hybrid power trains is formally described and several numerical solutions detailed, including dynamic programming and a novel solution for state-constrained optimal control problems based on Pontryagin’s maximum principle.   Real-time-implementable strategies that can approximate the optimal solution closely are dealt with in depth. Several approaches are discussed and compared, including a state-of-the-art strategy which is adaptive for vehicle conditions like velocity and mass. Two case studies are included in the book: ·        a control strategy for a micro-hybrid power train; and ·        experimental results obtained with a real-time strategy implemented in...

  11. Hybridization in a warmer world.

    Science.gov (United States)

    Chunco, Amanda J

    2014-05-01

    Climate change is profoundly affecting the evolutionary trajectory of individual species and ecological communities, in part through the creation of novel species assemblages. How climate change will influence competitive interactions has been an active area of research. Far less attention, however, has been given to altered reproductive interactions. Yet, reproductive interactions between formerly isolated species are inevitable as populations shift geographically and temporally as a result of climate change, potentially resulting in introgression, speciation, or even extinction. The susceptibility of hybridization rates to anthropogenic disturbance was first recognized in the 1930s. To date, work on anthropogenically mediated hybridization has focused primarily on either physical habitat disturbance or species invasion. Here, I review recent literature on hybridization to identify how ecological responses to climate change will increase the likelihood of hybridization via the dissolution of species barriers maintained by habitat, time, or behavior. Using this literature, I identify several cases where novel hybrid zones have recently formed, likely as a result of changing climate. Future research should focus on identifying areas and taxonomic groups where reproductive species interactions are most likely to be influenced by climate change. Furthermore, a better understanding of the evolutionary consequences of climate-mediated secondary contact is urgently needed. Paradoxically, hybridization is both a major conservation concern and an important source of novel genetic and phenotypic variation. Hybridization may therefore both contribute to increasing rates of extinction and stimulate the creation of novel phenotypes that will speed adaptation to novel climates. Predicting which result will occur following secondary contact will be an important contribution to conservation for many species.

  12. Copper-Catalyzed Aerobic Oxidations of Organic Molecules: Pathways for Two-Electron Oxidation with a Four-Electron Oxidant and a One-Electron Redox-Active Catalyst.

    Science.gov (United States)

    McCann, Scott D; Stahl, Shannon S

    2015-06-16

    Selective oxidation reactions have extraordinary value in organic chemistry, ranging from the conversion of petrochemical feedstocks into industrial chemicals and polymer precursors to the introduction of heteroatom functional groups into pharmaceutical and agrochemical intermediates. Molecular oxygen (O2) would be the ideal oxidant for these transformations. Whereas many commodity-scale oxidations of simple hydrocarbon feedstocks employ O2 as an oxidant, methods for selective oxidation of more complex molecules bearing diverse functional groups are often incompatible with existing aerobic oxidation methods. The latter limitation provides the basis for our interest in the development of new catalytic transformations and the elucidation of mechanistic principles that underlie selective aerobic oxidation reactions. One challenge inherent in such methods is the incommensurate redox stoichiometry associated with the use of O2, a four-electron oxidant, in reactions that achieve two-electron oxidation of organic molecules. This issue is further complicated by the use of first-row transition-metal catalysts, which tend to undergo facile one-electron redox steps. In recent years, we have been investigating Cu-catalyzed aerobic oxidation reactions wherein the complexities just noted are clearly evident. This Account surveys our work in this area, which has emphasized three general classes of reactions: (1) single-electron-transfer reactions for oxidative functionalization of electron-rich substrates, such as arenes and heterocycles; (2) oxidative carbon-heteroatom bond-forming reactions, including C-H oxidations, that proceed via organocopper(III) intermediates; and (3) methods for aerobic oxidation of alcohols and amines that use Cu(II) in combination with an organic redox-active cocatalyst to dehydrogenate the carbon-heteroatom bond. These reaction classes demonstrate three different pathways to achieve two-electron oxidation of organic molecules via the cooperative

  13. Direct Observation by Rapid-Scan FT-IR Spectroscopy of Two-Electron-Reduced Intermediate of Tetraaza Catalyst [Co(II)N4H(MeCN)](2+) Converting CO2 to CO.

    Science.gov (United States)

    Sheng, Hua; Frei, Heinz

    2016-08-10

    In the search for the two-electron-reduced intermediate of the tetraaza catalyst [Co(II)N4H(MeCN)](2+) (N4H = 2,12-dimethyl-3,7,11,17-tetraazabicyclo[11.3.1]heptadeca-1(17),2,11,13,15-pentaene) for CO2 reduction and elementary steps that result in the formation of CO product, rapid-scan FT-IR spectroscopy of the visible-light-sensitized catalysis, using Ir(ppy)3 in wet acetonitrile (CD3CN) solution, led to the observation of two sequential intermediates. The initially formed one-electron-reduced [Co(I)N4H](+)-CO2 adduct was converted by the second electron to a transient [Co(I)N4H](+)-CO2(-) complex that spontaneously converted CO2 to CO in a rate-limiting step on the second time scale in the dark under regeneration of the catalyst (room temperature). The macrocycle IR spectra of the [Co(I)N4H](+)-CO2(-) complex and the preceding one-electron [Co(I)N4H](+)-CO2 intermediate show close similarity but distinct differences in the carboxylate modes, indicating that the second electron resides mainly on the CO2 ligand. Vibrational assignments are corroborated by (13)C isotopic labeling. The structure and stability of the two-electron-reduced intermediate derived from the time-resolved IR study are in good agreement with recent predictions by DFT electronic structure calculations. This is the first observation of an intermediate of a molecular catalyst for CO2 reduction during the bond-breaking step producing CO. The reaction pathway for the Co tetraaza catalyst uncovered here suggests that the competition between CO2 reduction and proton reduction of a macrocyclic multi-electron catalyst is steered toward CO2 activation if the second electron is directly captured by an adduct of CO2 and the one-electron-reduced catalyst intermediate.

  14. DC and AC voltammetry of a free-base porphyrin adsorbed onto basal-plane graphite under acidic conditions: An example of a close to ideal reversible two-electron surface-confined redox process at sub-monolayer coverages

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Barry D. [School of Chemistry, Monash University, Wellington Rd, Clayton, Victoria 3800 (Australia)], E-mail: barry.fleming@sci.monash.edu.au; Bond, Alan M. [School of Chemistry, Monash University, Wellington Rd, Clayton, Victoria 3800 (Australia)], E-mail: alan.bond@sci.monash.edu.au

    2009-04-01

    The free-base porphyrin, 5,10,15,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphine (H{sub 2}TMPyP), adsorbs onto a basal-plane graphite electrode. Under DC cyclic voltammetric conditions, the fully protonated dication, [H{sub 4}TMPyP(0)]{sup 2+}, undergoes an apparently close to ideal surface-confined two-electron reduction to the neutral [H{sub 4}TMPyP(-II)] species when the supporting electrolyte consists of aqueous 1 M HCl and 1 M NaCl and coverages are sub-monolayer. The reversible potential calculated from the average of the oxidation and reduction peak potentials is 0.138 {+-} 0.002 V (vs Ag/AgCl, 3 M NaCl) whilst their separation {delta}E{sub p}, approaches 0 mV at slow scan rates, as expected theoretically for an ideal surface-confined electron transfer process. Comparisons of simulated and experimental data imply that the increase in {delta}E{sub p} observed at scan rates above 10 V s{sup -1} is consistent with uncompensated Ohmic IR{sub u} drop effects, and not limitations imposed by electron transfer kinetics. Analysis of fundamental and higher harmonic components derived from large-amplitude sine-wave AC voltammetry is consistent with a very fast electron transfer rate constant, k{sup 0}, in excess of 10{sup 6} s{sup -1} for the overall two-electron process. However, careful comparison with AC theory highlights minor levels of non-ideality not attributable to purely capacitative background or uncompensated resistance effects. These are particularly evident when greater than monolayer surface coverages are employed. It is likely that subtle contributions from heterogeneity in the adsorbed layer and complexities in the reaction mechanism are present in this close to ideal surface-confined process, but they are more readily detected under conditions of large-amplitude Fourier transformed AC cyclic voltammetry than with the conventionally used DC cyclic format.

  15. Hybrid origins of cultivated potatoes.

    Science.gov (United States)

    Rodríguez, Flor; Ghislain, Marc; Clausen, Andrea M; Jansky, Shelley H; Spooner, David M

    2010-10-01

    Solanum section Petota is taxonomically difficult, partly because of interspecific hybridization at both the diploid and polyploid levels. The taxonomy of cultivated potatoes is particularly controversial. Using DNA sequence data of the waxy gene, we here infer relationships among the four species of cultivated potatoes accepted in the latest taxonomic treatment (S. ajanhuiri, S. curtilobum, S. juzepczukii and S. tuberosum, the latter divided into the Andigenum and Chilotanum Cultivar Groups). The data support prior ideas of hybrid origins of S. ajanhuiri from the S. tuberosum Andigenum Group (2x = S. stenotomum) × S. megistacrolobum; S. juzepczukii from the S. tuberosum Andigenum Group (2x = S. stenotomum) × S. acaule; and S. curtilobum from the S. tuberosum Andigenum Group (4x = S. tuberosum subsp. andigenum) × S. juzepczukii. For the tetraploid cultivar-groups of S. tuberosum, hybrid origins are suggested entirely within much more closely related species, except for two of three examined accessions of the S. tuberosum Chilotanum Group that appear to have hybridized with the wild species S. maglia. Hybrid origins of the crop/weed species S. sucrense are more difficult to support and S. vernei is not supported as a wild species progenitor of the S. tuberosum Andigenum Group.

  16. Somatic hybridization in higher plants.

    Science.gov (United States)

    Constabel, F

    1976-11-01

    Somatic hybridization in higher plants has come into focus since methods have been established for protoplast fusion and uptake of foreign DNA and organelles by protoplasts. Polyethylene glycol (PEG) was an effective agent for inducing fusion. Treatment of protoplasts with PEG resulted in 5 to 30% heterospecific fusion products. Protoplasts of different species, genera and even families were compatible when fused. A number of protoplast combinations (soybean + corn, soybean + pea, soybean + tobacco, carrot + barley, etc.) provided fusion products which underwent cell division and callus formation. Fusion products initially were heterokaryocytes. In dividing heterokaryocytes, random distribution of mitotic nuclei was observed to be accompanied by multiple wall formation and to result in chimeral callus. Juxtaposition of mitotic nuclei suggested nuclear fusion and hybrid formation. Fusion of heterospecific interphase nuclei was demonstrated in soybean + pea and carrot + barley heterokaryons. Provided parental protoplasts carry suitable markers, the fusion products can be recognized. For the isolation and cloning of hybrid cells, fusion experiments must be supplemented with a selective system. Complementation of two non-allelic genes that prevent or inhibit growth under special culture conditions appears as the principle on which to base the selection of somatic hybrids. As protoplasts of some species have been induced to regenerate entire plants, the development of hybrid plants from protoplast fusion products is feasible and has already been demonstrated for tobacco.

  17. Symbolic Algorithmic Analysis of Rectangular Hybrid Systems

    Institute of Scientific and Technical Information of China (English)

    Hai-Bin Zhang; Zhen-Hua Duan

    2009-01-01

    This paper investigates symbolic algorithmic analysis of rectangular hybrid systems. To deal with the symbolic reachability problem, a restricted constraint system called hybrid zone is formalized for the representation and manipulation of rectangular automata state-spaces. Hybrid zones are proved to be closed over symbolic reachability operations of rectangular hybrid systems. They are also applied to model-checking procedures for verifying some important classes of timed computation tree logic formulas. To represent hybrid zones, a data structure called difference constraint matrix is defined.These enable us to deal with the symbolic algorithmic analysis of rectangular hybrid systems in an efficient way.

  18. Enhanced computational efficiency in the direct determination of the two-electron reduced density matrix from the anti-Hermitian contracted Schrödinger equation with application to ground and excited states of conjugated π-systems

    Energy Technology Data Exchange (ETDEWEB)

    Sand, Andrew M.; Mazziotti, David A., E-mail: damazz@uchicago.edu [Department of Chemistry and The James Franck Institute, The University of Chicago, Chicago, Illinois 60637 (United States)

    2015-10-07

    Determination of the two-electron reduced density matrix (2-RDM) from the solution of the anti-Hermitian contracted Schrödinger equation (ACSE) yields accurate energies and properties for both ground and excited states. Here, we develop a more efficient method to solving the ACSE that uses second-order information to select a more optimal step towards the solution. Calculations on the ground and excited states of water, hydrogen fluoride, and conjugated π systems show that the improved ACSE algorithm is 10-20 times faster than the previous ACSE algorithm. The ACSE can treat both single- and multi-reference electron correlation with the initial 2-RDM from a complete-active-space self-consistent-field (CASSCF) calculation. Using the improved algorithm, we explore the relationship between truncation of the active space in the CASSCF calculation and the accuracy of the energy and 2-RDM from the ACSE calculation. The accuracy of the ACSE, we find, is less sensitive to the size of the active space than the accuracy of other wavefunction methods, which is useful when large active space calculations are computationally infeasible.

  19. Density functional theory and atoms-in-molecule study on the role of two-electron stabilizing interactions in retro Diels-Alder reaction of cycloadducts derived from substituted cyclopentadiene and p-benzoquinone.

    Science.gov (United States)

    Patil, Mahendra P; Sunoj, Raghavan B

    2006-11-07

    A systematic investigation on the cycloreversion reaction of the cycloadduct formed between substituted cyclopentadiene and p-benzoquinone (1-19) is reported at the B3LYP/6-311+G**//B3LYP/6-31G* level of theory. The computed activation barrier exhibits a fairly high sensitivity to the nature of substituents at the C7-position. Gibbs free energy of activation for 1 and 19 are found to be 20.3 and 30.1 kcal mol(-1), respectively, compared to 7, which is estimated to be 24.7 kcal mol(-1). Quantitative analysis of the electronic effects operating in both the cycloadduct as well as the corresponding transition state for the retro Diels-Alder (rDA) reaction performed using the natural bond orbital (NBO) and atoms in molecule (AIM) methods have identified important two-electron stabilizing interactions. Among four major delocalizations, sigma(C7-X) to sigma*(C1-C5) [and to sigma*(C2-C6)] is identified as the key contributing factor responsible for ground state C1-C5 bond elongation, which in turn is found to be crucial in promoting the rDA reaction. A good correlation between the population of antibonding orbital [sigma*(C1-C5)] of the ground state cycloadduct and Gibbs free energy of activation is observed. The importance of factors that modulate ground state structural features in controlling the energetics of rDA reaction is described.

  20. Enhanced computational efficiency in the direct determination of the two-electron reduced density matrix from the anti-Hermitian contracted Schrödinger equation with application to ground and excited states of conjugated π-systems.

    Science.gov (United States)

    Sand, Andrew M; Mazziotti, David A

    2015-10-01

    Determination of the two-electron reduced density matrix (2-RDM) from the solution of the anti-Hermitian contracted Schrödinger equation (ACSE) yields accurate energies and properties for both ground and excited states. Here, we develop a more efficient method to solving the ACSE that uses second-order information to select a more optimal step towards the solution. Calculations on the ground and excited states of water, hydrogen fluoride, and conjugated π systems show that the improved ACSE algorithm is 10-20 times faster than the previous ACSE algorithm. The ACSE can treat both single- and multi-reference electron correlation with the initial 2-RDM from a complete-active-space self-consistent-field (CASSCF) calculation. Using the improved algorithm, we explore the relationship between truncation of the active space in the CASSCF calculation and the accuracy of the energy and 2-RDM from the ACSE calculation. The accuracy of the ACSE, we find, is less sensitive to the size of the active space than the accuracy of other wavefunction methods, which is useful when large active space calculations are computationally infeasible.

  1. DNA-based hybrid catalysis.

    Science.gov (United States)

    Rioz-Martínez, Ana; Roelfes, Gerard

    2015-04-01

    In the past decade, DNA-based hybrid catalysis has merged as a promising novel approach to homogeneous (asymmetric) catalysis. A DNA hybrid catalysts comprises a transition metal complex that is covalently or supramolecularly bound to DNA. The chiral microenvironment and the second coordination sphere interactions provided by the DNA are key to achieve high enantioselectivities and, often, additional rate accelerations in catalysis. Nowadays, current efforts are focused on improved designs, understanding the origin of the enantioselectivity and DNA-induced rate accelerations, expanding the catalytic scope of the concept and further increasing the practicality of the method for applications in synthesis. Herein, the recent developments will be reviewed and the perspectives for the emerging field of DNA-based hybrid catalysis will be discussed.

  2. Model Reduction of Hybrid Systems

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza

    systems are derived in this thesis. The results are used for output feedback control of switched nonlinear systems. Model reduction of piecewise affine systems is also studied in this thesis. The proposed method is based on the reduction of linear subsystems inside the polytopes. The methods which......High-Technological solutions of today are characterized by complex dynamical models. A lot of these models have inherent hybrid/switching structure. Hybrid/switched systems are powerful models for distributed embedded systems design where discrete controls are applied to continuous processes...... of hybrid systems, designing controllers and implementations is very high so that the use of these models is limited in applications where the size of the state space is large. To cope with complexity, model reduction is a powerful technique. This thesis presents methods for model reduction and stability...

  3. Additive Manufacturing of Hybrid Circuits

    Science.gov (United States)

    Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David; Hirschfeld, Deidre; Hall, Aaron C.; Bell, Nelson S.

    2016-07-01

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.

  4. Intercalated hybrid graphite fiber composite

    Science.gov (United States)

    Gaier, James R. (Inventor)

    1993-01-01

    The invention is directed to a highly conductive lightweight hybrid material and methods of producing the same. The hybrid composite is obtained by weaving strands of a high strength carbon or graphite fiber into a fabric-like structure, depositing a layer of carbon onto the structure, heat treating the structure to graphitize the carbon layer, and intercalating the graphitic carbon layer structure. A laminate composite material useful for protection against lightning strikes comprises at least one layer of the hybrid material over at least one layer of high strength carbon or graphite fibers. The composite material of the present invention is compatible with matrix compounds, has a coefficient of thermal expansion which is the same as underlying fiber layers, and is resistant to galvanic corrosion in addition to being highly conductive. These materials are useful in the aerospace industry, in particular as lightning strike protection for airplanes.

  5. Optimizing Hybrid Spreading in Metapopulations

    CERN Document Server

    Zhang, Changwang; Cox, Ingemar J; Chain, Benjamin M

    2014-01-01

    Epidemic spreading phenomena are ubiquitous in nature and society. Examples include the spreading of diseases, information, and computer viruses. Epidemics can spread by \\textit{local spreading}, where infected nodes can only infect a limited set of direct target nodes and \\textit{global spreading}, where an infected node can infect every other node. In reality, many epidemics spread using a hybrid mixture of both types of spreading. In this study we develop a theoretical framework for studying hybrid epidemics, and examine the optimum balance between spreading mechanisms in terms of achieving the maximum outbreak size. In a metapopulation, made up of many weakly connected subpopulations, we show that one can calculate an optimal tradeoff between local and global spreading which will maximise the extent of the epidemic. As an example we analyse the 2008 outbreak of the Internet worm Conficker, which uses hybrid spreading to propagate through the internet. Our results suggests that the worm would have been eve...

  6. New Supercapacitors of Hybrid Configurations

    Directory of Open Access Journals (Sweden)

    Wako Naoi

    2013-01-01

    Full Text Available In recent years, the improvement of the energydensity of nano-composite battery materials hasbeen object of great study. Hybridizing battery andcapacitor materials overcome the energy densitylimitation of existing generation-I capacitors withoutmuch sacrificing the cycling performances. Normalbattery-capacitor hybrids employ high-energy &sluggish redox electrode and low-energy & fastdouble-layer electrodes, possibly producing a largerworking voltage and higher over-all capacitance. Inorder to smoothly operate such asymmetric systems,however, the rates of the two different electrodes mustbe highly balanced. Especially, the redox rates of thebattery electrodes must be substantially increasedto the levels of double-layer process. In this report,we attempt to identify the essential issues for therealizable hybrids and suggest ways to overcomethe rate enhancement by exemplifying ultrafastperformance of the Li4Ti5O12 nanocrystal preparedvia a unique in-situ material processing technologyunder ultra-centrifuging.

  7. Genomic networks of hybrid sterility.

    Directory of Open Access Journals (Sweden)

    Leslie M Turner

    2014-02-01

    Full Text Available Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci ("Dobzhansky-Muller incompatibilities". The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL. Many trans eQTL cluster into eleven 'hotspots,' seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL-but not cis eQTL-were substantially lower when mapping was restricted to a 'fertile' subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is

  8. Genomic networks of hybrid sterility.

    Science.gov (United States)

    Turner, Leslie M; White, Michael A; Tautz, Diethard; Payseur, Bret A

    2014-02-01

    Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci ("Dobzhansky-Muller incompatibilities"). The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus) provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven 'hotspots,' seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL-but not cis eQTL-were substantially lower when mapping was restricted to a 'fertile' subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is applicable in a broad

  9. Interspecific Hybridization within Ornamental Plants

    DEFF Research Database (Denmark)

    Kuligowska, Katarzyna

    The economic importance of the ornamental plant industry requires constant development of novel and high quality varieties. Traits attractive for production of new ornamental plants may not be available within the commercial cultivars, but broad genetic variation is present within the plant genera...... commercially important genera of ornamental plants: Kalanchoë and Hibiscus. The nature of hybridization barriers hampering hybrid production was investigated during pre- and post-fertilization stages. For each genus the interspecific crosses of Kalanchoë species and Hibiscus species, abnormal germination...

  10. Essentialism, hybridism and cultural critique

    DEFF Research Database (Denmark)

    Frello, Birgitta

    2007-01-01

    to social and cultural critique. Through a critical discussion of the concept of hybridity, I argue that rather than expecting to find definite emancipating or suppressing capacities connected to constructions of the ‘hybrid' and the ‘pure', we should focus on how these two poles are invested with meaning...... assuming that certain social forms carry a critical, emancipating or suppressing potential per se....... and related to power. Hence, while insisting on Cultural Studies' commitment to social and cultural critique, I argue that this critique would benefit from an analytical sensitivity towards the uses and abuses of the discursive power to designate meaningful and legitimate subject positions, rather than...

  11. Towards an expansive hybrid psychology

    DEFF Research Database (Denmark)

    Brinkmann, Svend

    2011-01-01

    This article develops an integrative theory of the mind by examining how the mind, understood as a set of skills and dispositions, depends upon four sources of mediators. Harré’s hybrid psychology is taken as a meta-theoretical starting point, but is expanded significantly by including the four...... sources of mediators that are the brain, the body, social practices and technological artefacts. It is argued that the mind is normative in the sense that mental processes do not simply happen, but can be done more or less well, and thus are subject to normative appraisal. The expanded hybrid psychology...

  12. Hybrid Simulation of Composite Structures

    DEFF Research Database (Denmark)

    Høgh, Jacob Herold

    Hybrid simulation is a substructural method combining a numerical simulation with a physical experiment. A structure is thereby simulated under the assumption that a substructure’s response is well known and easily modelled while a given substructure is studied more accurately in a physical...... of freedom. In this dissertation the main focus is to develop hybrid simulation for composite structures e.g. wind turbine blades where the boundary between the numerical model and the physical experiment is continues i.e. in principal infinite amount of degrees of freedom. This highly complicates...

  13. Charge Qubit-Atom Hybrid

    CERN Document Server

    Yu, Deshui; Hufnagel, C; Kwek, L C; Amico, Luigi; Dumke, R

    2016-01-01

    We investigate a novel hybrid system of a superconducting charge qubit interacting directly with a single neutral atom via electric dipole coupling. Interfacing of the macroscopic superconducting circuit with the microscopic atomic system is accomplished by varying the gate capacitance of the charge qubit. To achieve strong interaction, we employ two Rydberg states with an electric-dipole-allowed transition, which alters the polarizability of the dielectric medium of the gate capacitor. Sweeping the gate voltage with different rates leads to a precise control of hybrid quantum states. Furthermore, we show a possible implementation of a universal two-qubit gate.

  14. Position list word aligned hybrid

    DEFF Research Database (Denmark)

    Deliege, Francois; Pedersen, Torben Bach

    2010-01-01

    Compressed bitmap indexes are increasingly used for efficiently querying very large and complex databases. The Word Aligned Hybrid (WAH) bitmap compression scheme is commonly recognized as the most efficient compression scheme in terms of CPU efficiency. However, WAH compressed bitmaps use a lot...... of storage space. This paper presents the Position List Word Aligned Hybrid (PLWAH) compression scheme that improves significantly over WAH compression by better utilizing the available bits and new CPU instructions. For typical bit distributions, PLWAH compressed bitmaps are often half the size of WAH...

  15. Interspecific Hybridization within Ornamental Plants

    DEFF Research Database (Denmark)

    Kuligowska, Katarzyna

    The economic importance of the ornamental plant industry requires constant development of novel and high quality varieties. Traits attractive for production of new ornamental plants may not be available within the commercial cultivars, but broad genetic variation is present within the plant genera...... commercially important genera of ornamental plants: Kalanchoë and Hibiscus. The nature of hybridization barriers hampering hybrid production was investigated during pre- and post-fertilization stages. For each genus the interspecific crosses of Kalanchoë species and Hibiscus species, abnormal germination...

  16. Hybrid winding concept for toroids

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold;

    2013-01-01

    This paper proposes a hybrid winding concept for toroids using the traces in a printed circuit board to make connection to bended copper foil cutouts. In a final product a number of strips with a certain thickness would be held by a former and the whole assembly could be placed by pick...... and placement machinery. This opens up the possibility for both an automated manufacturing process and an automated production process of toroidal magnetics such as power inductors, filtering inductors, air core inductors, transformers etc. Both the proposed hybrid and the common wire wound winding...

  17. Energy Efficiency Comparison between Hydraulic Hybrid and Hybrid Electric Vehicles

    OpenAIRE

    Jia-Shiun Chen

    2015-01-01

    Conventional vehicles tend to consume considerable amounts of fuel, which generates exhaust gases and environmental pollution during intermittent driving cycles. Therefore, prospective vehicle designs favor improved exhaust emissions and energy consumption without compromising vehicle performance. Although pure electric vehicles feature high performance and low pollution characteristics, their limitations are their short driving range and high battery costs. Hybrid electric vehicles (HEVs) ar...

  18. ADVANCED HYBRID PARTICULATE COLLECTOR

    Energy Technology Data Exchange (ETDEWEB)

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  19. Hybrid Power Management System and Method

    Science.gov (United States)

    Eichenberg, Dennis J. (Inventor)

    2008-01-01

    A system and method for hybrid power management. The system includes photovoltaic cells, ultracapacitors, and pulse generators. In one embodiment, the hybrid power management system is used to provide power for a highway safety flasher.

  20. Field errors in hybrid insertion devices

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, R.D. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Hybrid magnet theory as applied to the error analyses used in the design of Advanced Light Source (ALS) insertion devices is reviewed. Sources of field errors in hybrid insertion devices are discussed.

  1. How to distinguish Hybrids from Radial Quarkonia

    CERN Document Server

    Close, Francis Edwin; Close, Frank E; Page, Philip R.

    1997-01-01

    We present arguments that reinforce the hybrid interpretation of pi(1800) and we establish that the rho(1450) and the omega(1420) can be interpreted as radial-hybrid mixtures. Some questions for future experiments are raised.

  2. Modeling and analysis using hybrid Petri nets

    CERN Document Server

    Ghomri, Latéfa

    2007-01-01

    This paper is devoted to the use of hybrid Petri nets (PNs) for modeling and control of hybrid dynamic systems (HDS). Modeling, analysis and control of HDS attract ever more of researchers' attention and several works have been devoted to these topics. We consider in this paper the extensions of the PN formalism (initially conceived for modeling and analysis of discrete event systems) in the direction of hybrid modeling. We present, first, the continuous PN models. These models are obtained from discrete PNs by the fluidification of the markings. They constitute the first steps in the extension of PNs toward hybrid modeling. Then, we present two hybrid PN models, which differ in the class of HDS they can deal with. The first one is used for deterministic HDS modeling, whereas the second one can deal with HDS with nondeterministic behavior. Keywords: Hybrid dynamic systems; D-elementary hybrid Petri nets; Hybrid automata; Controller synthesis

  3. Fundamentals of Hybrid Teaching and Learning

    Science.gov (United States)

    Linder, Kathryn E.

    2017-01-01

    This chapter provides definitions and distinguishing characteristics of the various terms used in the context of hybrid education. The author also offers an overview of the recent literature on hybrid teaching and learning.

  4. Distant hybridization leads to different ploidy fishes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (♂), and RCC (2n=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including

  5. Distant hybridization leads to different ploidy fishes.

    Science.gov (United States)

    Liu, ShaoJun

    2010-04-01

    Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (female) x common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (male), and RCC (2n=100) (female) x blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (male) are described. In the distant hybridization of RCC (female) x CC (male), bisexual fertile F(3)-F(18) allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (female) x BSB (male), different ploidy fishes were

  6. Continuity and invariance in hybrid automata

    OpenAIRE

    Lygeros, John; Johansson, Karl H.; Simic, Slobodan; ZHANG, JUN; Sastry, Shankar

    2001-01-01

    Hybrid automata have been proposed as a language for modelling and analysing the interaction of digital and analogue dynamics in embedded computer systems. In the paper, hybrid automata are studied from a dynamical systems perspective. Extending earlier work on conditions for existence and uniqueness of executions of hybrid automata, we characterise a class of hybrid automata whose executions depend continuously on the initial state. The continuity conditions are subsequently used to derive a...

  7. Advanced Digital Signal Processing for Hybrid Lidar

    Science.gov (United States)

    2014-10-30

    Technical 4. TITLE AND SUBTITLE Advance Digital Signal Processing for Hybrid Lidar 6. AUTHOR(S) William D. Jemison 7. PERFORMING ORGANIZATION NAME(S...development of signed processing algorithms for hybrid lidar - radar designed to improve detection performance. 15. SUBJECT TERMS Hybrid Lidar - Radar 16...Award Number N000141110371 Title of Research Advanced Digital Signal Processing for Hybrid Lidar Principal Investigator William D. Jemison

  8. Hybrid Warfare: Implications for CAF Force Development

    Science.gov (United States)

    2014-08-01

    also McCulloh and Johnson who demonstrate throughout their study that context is critical . Indeed, their summary statement for “hybrid warfare theory ...Muhr, eds., Hybrid and Cyber War as Consequences of the Asymmetry, Frankfurt : Peter Lang, 2011, p.95. Interestingly, the CFD Hybrid Warfare Concept...the highest political and military levels. The study of hybrid-type case studies yields the critical lesson that: “leadership is essential to victory

  9. Contribution of interspecific hybridization to sunflower breeding

    OpenAIRE

    Christov M.

    2012-01-01

    This investigation is directed at improving sunflower using hybrid forms resulted from interspecific hybridization. The aim is to create new B/A and R lines from interspecific hybrid forms that are resistant to diseases, the parasite broomrape, herbicides, and other stress factors and are characterized with high combining ability and to obtain on this basis highly productive oilseed sunflower hybrids with varied fatty acid composition of oil. The investigat...

  10. The Hybrid Automobile and the Atkinson Cycle

    Science.gov (United States)

    Feldman, Bernard J.

    2008-01-01

    The hybrid automobile is a strikingly new automobile technology with a number of new technological features that dramatically improve energy efficiency. This paper will briefly describe how hybrid automobiles work; what are these new technological features; why the Toyota Prius hybrid internal combustion engine operates on the Atkinson cycle…

  11. Hybrid Logical Analyses of the Ambient Calculus

    DEFF Research Database (Denmark)

    Bolander, Thomas; Hansen, Rene Rydhof

    2010-01-01

    In this paper, hybrid logic is used to formulate three control flow analyses for Mobile Ambients, a process calculus designed for modelling mobility. We show that hybrid logic is very well-suited to express the semantic structure of the ambient calculus and how features of hybrid logic can...

  12. The Hybrid Automobile and the Atkinson Cycle

    Science.gov (United States)

    Feldman, Bernard J.

    2008-01-01

    The hybrid automobile is a strikingly new automobile technology with a number of new technological features that dramatically improve energy efficiency. This paper will briefly describe how hybrid automobiles work; what are these new technological features; why the Toyota Prius hybrid internal combustion engine operates on the Atkinson cycle…

  13. Dynamical investigation of macromolecular hybridization bioassays

    CERN Document Server

    Bittner, R; Wixforth, A

    2002-01-01

    A novel sensoric technique for the dynamical in situ investigation of a hybridization bio assay is presented, which utilizes a metal bead labeling method. Therein, hybridization results in an increased metal coverage on parts of a substrate, where it takes place. Our sensing principle relies on the measurement of the radio frequency impedance of the hybridization spots. We propose several examples for sensor devices.

  14. Internal combustion engines in hybrid vehicles

    NARCIS (Netherlands)

    Mourad, S.; Weijer, C.J.T. van de; Beckman, D.E.

    1998-01-01

    In this paper the use of internal combustion engines in hybrid powertrains is investigated. The substantial difference between the use of internal combustion engines in conventional and in hybrid vehicles mean that engines for hybrid vehicles should be designed specifically for the purpose. At the

  15. Hybrid Doctoral Program: Innovative Practices and Partnerships

    Science.gov (United States)

    Alvich, Dori; Manning, JoAnn; McCormick, Kathy; Campbell, Robert

    2012-01-01

    This paper reflects on how one mid-Atlantic University innovatively incorporated technology into the development of a hybrid doctoral program in educational leadership. The paper describes a hybrid doctoral degree program using a rigorous design; challenges of reworking a traditional syllabus of record to a hybrid doctoral program; the perceptions…

  16. Inference in hybrid Bayesian networks

    DEFF Research Database (Denmark)

    Lanseth, Helge; Nielsen, Thomas Dyhre; Rumí, Rafael

    2009-01-01

    Since the 1980s, Bayesian Networks (BNs) have become increasingly popular for building statistical models of complex systems. This is particularly true for boolean systems, where BNs often prove to be a more efficient modelling framework than traditional reliability-techniques (like fault trees...... decade's research on inference in hybrid Bayesian networks. The discussions are linked to an example model for estimating human reliability....

  17. Hybrid Rice for Dry Regions

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Luo Lijun, director of the Shanghai Agrobiological Gene Center, recently announced that Hanyou No. 3 - a genetically modified rice capable of producing high yields in dry areas - has been developed at the center.The hybrid yields 7,571 kilograms per hectare, about the same as ordinary rice.

  18. Yeast two-hybrid screen.

    Science.gov (United States)

    Makuch, Lauren

    2014-01-01

    Yeast two-hybrid is a method for screening large numbers of gene products (encoded by cDNA libraries) for their ability to interact with a protein of interest. This system can also be used for characterizing and manipulating candidate protein: protein interactions. Interactions between proteins are monitored by the growth of yeast plated on selective media.

  19. Comparative genomic hybridization: practical guidelines.

    NARCIS (Netherlands)

    Jeuken, J.W.M.; Sprenger, S.H.; Wesseling, P.

    2002-01-01

    Comparative genomic hybridization (CGH) is a technique used to identify copy number changes throughout a genome. Until now, hundreds of CGH studies have been published reporting chromosomal imbalances in a large variety of human neoplasms. Additionally, technical improvements of specific steps in a

  20. Multifunctional hybrids for electromagnetic absorption

    Energy Technology Data Exchange (ETDEWEB)

    Huynen, I. [Research Center in Micro and Nanoscopic Materials and Electronic Devices, CeRMiN, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Quievy, N. [Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Bailly, C. [Research Center in Micro and Nanoscopic Materials and Electronic Devices, CeRMiN, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Mechanics, Materials and Civil Engineering (iMMC), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Bollen, P. [Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Condensed Matter and Nanosciences (IMCN), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Institute of Mechanics, Materials and Civil Engineering (iMMC), Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Detrembleur, C. [Center for Education and Research on Macromolecules (CERM), University of Liege, Sart-Tilman B6a, 4000 Liege (Belgium); Eggermont, S.; Molenberg, I. [Information and Communications Technologies, Electronics and Applied Mathematics (ICTEAM), Microwave Laboratory, Universite catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Thomassin, J.M.; Urbanczyk, L. [Center for Education and Research on Macromolecules (CERM), University of Liege, Sart-Tilman B6a, 4000 Liege (Belgium)

    2011-05-15

    Highlights: > EM absorption requires low dielectric constant and {approx}1 S/m electrical conductivity. > New hybrids were processed with CNT-filled polymer foam inserted in Al honeycomb. > The EM absorption in the GHz range is superior to any known material. > A closed form model is used to guide the design of the hybrid. > The architectured material is light with potential for thermal management. - Abstract: Electromagnetic (EM) interferences are ubiquitous in modern technologies and impact on the reliability of electronic devices and on living cells. Shielding by EM absorption, which is preferable over reflection in certain instances, requires combining a low dielectric constant with high electrical conductivity, which are antagonist properties in the world of materials. A novel class of hybrid materials for EM absorption in the gigahertz range has been developed based on a hierarchical architecture involving a metallic honeycomb filled with a carbon nanotube-reinforced polymer foam. The waveguide characteristics of the honeycomb combined with the performance of the foam lead to unexpectedly large EM power absorption over a wide frequency range, superior to any known material. The peak absorption frequency can be tuned by varying the shape of the honeycomb unit cell. A closed form model of the EM reflection and absorption provides a tool for the optimization of the hybrid. This designed material sets the stage for a new class of sandwich panels combining high EM absorption with mass efficiency, stiffness and thermal management.

  1. Hybrid Model of Content Extraction

    DEFF Research Database (Denmark)

    Qureshi, Pir Abdul Rasool; Memon, Nasrullah

    2012-01-01

    We present a hybrid model for content extraction from HTML documents. The model operates on Document Object Model (DOM) tree of the corresponding HTML document. It evaluates each tree node and associated statistical features like link density and text distribution across the node to predict signi...

  2. A HYBRID DYNAMIC PROGRAM SLICING

    Institute of Scientific and Technical Information of China (English)

    Yi Tong; Wu Fangjun

    2005-01-01

    This letter proposes a hybrid method for computing dynamic program slicing. The key element is to construct a Coverage-Testing-based Dynamic Dependence Graph (CTDDG),which makes use of both dynamic and static information to get execution status. The approach overcomes the limitations of previous dynamic slicing methods, which have to redo slicing if slice criterion changes.

  3. Hybrid Magnetics and Power Applications

    DEFF Research Database (Denmark)

    Mo, Wai Keung; Paasch, Kasper

    A hybrid magnetic approach, merging two different magnetic core properites such as ferrite and iron powder cores, is an effective solution for power converter applications. It can offer similar magnetic properties to that of magnetic powder cores but showing less copper loss than powder cores...

  4. Hybrid winding concept for toroids

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold;

    2013-01-01

    This paper proposes a hybrid winding concept for toroids using the traces in a printed circuit board to make connection to bended copper foil cutouts. In a final product a number of strips with a certain thickness would be held by a former and the whole assembly could be placed by pick and placem...

  5. Sugar pine and its hybrids

    Science.gov (United States)

    W. B. Critchfield; B. B. Kinloch

    1986-01-01

    Unlike most white pines, sugar pine (Pinus lambertiana) is severely restricted in its ability to hybridize with other species. It has not been successfully crossed with any other North American white pine, nor with those Eurasian white pines it most closely resembles. Crosses with the dissimilar P. koraiensis and P....

  6. Organic and hybrid solar cells

    CERN Document Server

    Huang, Hui

    2014-01-01

    This book delivers a comprehensive evaluation of organic and hybrid solar cells and identifies their fundamental principles and numerous applications. Great attention is given to the charge transport mechanism, donor and acceptor materials, interfacial materials, alternative electrodes, device engineering and physics, and device stability. The authors provide an industrial perspective on the future of photovoltaic technologies.

  7. Expanding discourse repertoires with hybridity

    Science.gov (United States)

    Kelly, Gregory J.

    2012-09-01

    In "Hybrid discourse practice and science learning" Kamberelis and Wehunt present a theoretically rich argument about the potential of hybrid discourses for science learning. These discourses draw from different forms of "talk, social practice, and material practices" to create interactions that are "intertextually complex" and "interactionally dynamic." The hybrid discourse practices are described as involving the dynamic interplay of at least three key elements: "the lamination of multiple cultural frames, the shifting relations between people and their discourse, and the shifting power relations between and among people." Each of these elements requires a respective unit of analysis and are often mutually reinforcing. The authors present a theoretically cogent argument for the study of hybrid discourse practices and identify the potential such discourses may have for science education. This theoretical development leads to an analysis of spoken and written discourse around a set of educational events concerning the investigation of owl pellets by two fifth grade students, their classmates, and teacher. Two discourse segments are presented and analyzed by the authors in detail. The first is a discourse analysis of the dissection of the owl pellet by two students, Kyle and Max. The second analysis examines the science report of these same two students. In this article, I pose a number of questions about the study with the hope that by doing so I expand the conversation around the insightful analysis presented.

  8. 32 tesla hybrid magnet system

    Energy Technology Data Exchange (ETDEWEB)

    Leupold, M.J.; Iwasa, Y.; Weggel, R.J. (MIT Cambridge (U.S.A.))

    1984-01-01

    The paper describes the design and construction of a hybrid magnet system to generate 32T with 9MW of electrical power. The system consist of an 11T niobium-titanium superconducting magnet, a 1.8K/4.2K cryostat, and a high-performance, water-cooled Bitter magnet, all of which are discussed in the paper.

  9. Hybrid origin of Audubon's warbler.

    Science.gov (United States)

    Brelsford, Alan; Milá, Borja; Irwin, Darren E

    2011-06-01

    Several animal species have recently been shown to have hybrid origins, but no avian examples have been documented with molecular evidence. We investigate whether the Audubon's warbler (Dendroica auduboni), one of four visually distinct species in the yellow-rumped warbler complex, has originated through hybridization between two other species in this group, the myrtle warbler (D. coronata) and black-fronted warbler (D. nigrifrons). Analysis of nuclear amplified fragment length polymorphism (AFLP) and sequence markers shows that Audubon's warblers are genetically intermediate and carry a mixture of alleles otherwise found only in one or the other of their putative parental species. Audubon's warblers also carry two deeply divergent mitochondrial DNA lineages, each shared with only one putative parental form. Broad clines between Audubon's and black-fronted warblers in AFLP markers call into question the validity of these two forms as full species; nevertheless, our results suggest that the Audubon's warbler probably originated through hybridization between two long-diverged species. It is likely that more cases of avian species of hybrid origin will be revealed by surveys of variation in nuclear DNA and other traits. © 2011 Blackwell Publishing Ltd.

  10. Transgressive Hybrids as Hopeful Monsters.

    Science.gov (United States)

    Dittrich-Reed, Dylan R; Fitzpatrick, Benjamin M

    2013-06-01

    The origin of novelty is a critical subject for evolutionary biologists. Early geneticists speculated about the sudden appearance of new species via special macromutations, epitomized by Goldschmidt's infamous "hopeful monster". Although these ideas were easily dismissed by the insights of the Modern Synthesis, a lingering fascination with the possibility of sudden, dramatic change has persisted. Recent work on hybridization and gene exchange suggests an underappreciated mechanism for the sudden appearance of evolutionary novelty that is entirely consistent with the principles of modern population genetics. Genetic recombination in hybrids can produce transgressive phenotypes, "monstrous" phenotypes beyond the range of parental populations. Transgressive phenotypes can be products of epistatic interactions or additive effects of multiple recombined loci. We compare several epistatic and additive models of transgressive segregation in hybrids and find that they are special cases of a general, classic quantitative genetic model. The Dobzhansky-Muller model predicts "hopeless" monsters, sterile and inviable transgressive phenotypes. The Bateson model predicts "hopeful" monsters with fitness greater than either parental population. The complementation model predicts both. Transgressive segregation after hybridization can rapidly produce novel phenotypes by recombining multiple loci simultaneously. Admixed populations will also produce many similar recombinant phenotypes at the same time, increasing the probability that recombinant "hopeful monsters" will establish true-breeding evolutionary lineages. Recombination is not the only (or even most common) process generating evolutionary novelty, but might be the most credible mechanism for sudden appearance of new forms.

  11. Review of laser hybrid welding

    DEFF Research Database (Denmark)

    Bagger, Claus

    2004-01-01

    In this artucle an overview og the hybrid welding process is given. After a short historic overview, a review of the fundamental phenomenon taking place when a laser (CO2 or Nd:YAG) interacts in the same molten pool as a more conventional source of energy, e.g. tungsten in-active gas, plasma...

  12. Review of laser hybrid welding

    DEFF Research Database (Denmark)

    Bagger, Claus

    2004-01-01

    In this artucle an overview og the hybrid welding process is given. After a short historic overview, a review of the fundamental phenomenon taking place when a laser (CO2 or Nd:YAG) interacts in the same molten pool as a more conventional source of energy, e.g. tungsten in-active gas, plasma...

  13. Hybrid Magnetics and Power Applications

    DEFF Research Database (Denmark)

    Mo, Wai Keung; Paasch, Kasper

    2017-01-01

    . In order to prevent ferrite core saturation, placing an effective air gap within the ferrite core is a key method to obtain optimum hybrid magnetic performance. Furthermore, a relatively large inductance at low loading current is an excellent way to minimze power loss in order to achieve high efficiency...

  14. Accessibility Considerations for Hybrid Courses

    Science.gov (United States)

    Behling, Kirsten

    2017-01-01

    This chapter explores the central questions and issues that faculty and administrators need to consider when designing and implementing hybrid courses to ensure that all students, including those with disabilities, have equal access. The author offers resources on faculty development programs, accessibility checklists, and online resources on…

  15. 1997 hybrid electric vehicle specifications

    Energy Technology Data Exchange (ETDEWEB)

    Sluder, S.; Larsen, R.; Duoba, M.

    1996-10-01

    The US DOE sponsors Advanced Vehicle Technology competitions to help educate the public and advance new vehicle technologies. For several years, DOE has provided financial and technical support for the American Tour de Sol. This event showcases electric and hybrid electric vehicles in a road rally across portions of the northeastern United States. The specifications contained in this technical memorandum apply to vehicles that will be entered in the 1997 American Tour de Sol. However, the specifications were prepared to be general enough for use by other teams and individuals interested in developing hybrid electric vehicles. The purpose of the specifications is to ensure that the vehicles developed do not present a safety hazard to the teams that build and drive them or to the judges, sponsors, or public who attend the competitions. The specifications are by no means the definitive sources of information on constructing hybrid electric vehicles - as electric and hybrid vehicles technologies advance, so will the standards and practices for their construction. In some cases, the new standards and practices will make portions of these specifications obsolete.

  16. 高校图书馆电子阅览室二室三制管理的服务创新%Service Innovation of Implementing Three Kinds of Management Modes in Two Electronic Reading Rooms

    Institute of Scientific and Technical Information of China (English)

    祁家能

    2012-01-01

    After going through the rising,developing and perfecting stages,the development of electronic reading rooms in college libraries now faces many new difficulties.So it is necessary to reconsider and reform the construction of the electronic reading room.It is advised to divide two electronic reading rooms into three areas which can offer free service,information retrieval service and special service respectively,so as to implement three kinds of management modes to meet the demands of different readers.The method is helpful to solve the development dilemma of the electronic reading rooms and give full play to the resources and facilities of the library.%高校图书馆电子阅览室从兴起、快速发展、成熟完善,到现在面临的诸多困境,促使我们对电子阅览室的建设要重新认识和进行理念创新。应该把两个电子阅览室分成辅助教学及读者自主学习区,信息检索学习区和个性化特色服务区三个区域,实行三种管理模式,满足不同读者的需求,走出电子阅览室发展的困境,使图书馆资源和设备发挥最大作用。

  17. Shape Memory Composite Hybrid Hinge

    Science.gov (United States)

    Fang, Houfei; Im, Eastwood; Lin, John; Scarborough, Stephen

    2012-01-01

    There are two conventional types of hinges for in-space deployment applications. The first type is mechanically deploying hinges. A typical mechanically deploying hinge is usually composed of several tens of components. It is complicated, heavy, and bulky. More components imply higher deployment failure probability. Due to the existence of relatively moving components among a mechanically deploying hinge, it unavoidably has microdynamic problems. The second type of conventional hinge relies on strain energy for deployment. A tape-spring hinge is a typical strain energy hinge. A fundamental problem of a strain energy hinge is that its deployment dynamic is uncontrollable. Usually, its deployment is associated with a large impact, which is unacceptable for many space applications. Some damping technologies have been experimented with to reduce the impact, but they increased the risks of an unsuccessful deployment. Coalescing strain energy components with shape memory composite (SMC) components to form a hybrid hinge is the solution. SMCs are well suited for deployable structures. A SMC is created from a high-performance fiber and a shape memory polymer resin. When the resin is heated to above its glass transition temperature, the composite becomes flexible and can be folded or packed. Once cooled to below the glass transition temperature, the composite remains in the packed state. When the structure is ready to be deployed, the SMC component is reheated to above the glass transition temperature, and it returns to its as-fabricated shape. A hybrid hinge is composed of two strain energy flanges (also called tape-springs) and one SMC tube. Two folding lines are placed on the SMC tube to avoid excessive strain on the SMC during folding. Two adapters are used to connect the hybrid hinge to its adjacent structural components. While the SMC tube is heated to above its glass transition temperature, a hybrid hinge can be folded and stays at folded status after the temperature

  18. Reproduction and hybrid load in all-hybrid populations of Rana esculenta water frogs in Denmark

    DEFF Research Database (Denmark)

    Christiansen, Ditte Guldager; Fog, Kåre; Pedersen, Bo Vest;

    2005-01-01

    All-hybrid populations of the water frog, Rana esculenta, are exceptional in consisting of independently and to some extent sexually reproducing interspecific hybrids. In most of its range R. esculenta reproduces hemiclonally with one of the parental species, R. lessonae or R. ridibunda, but viable...... gametogenesis and mating between frogs with incompatible gametes induce a significant hybrid load in all-hybrid populations of R. esculenta, and we discuss compensating advantages and potential evolutionary trajectories to reduce this hybrid load....

  19. SCAN-based hybrid and double-hybrid density functionals from models without fitted parameters

    OpenAIRE

    Hui, Kerwin; Chai, Jeng-Da

    2015-01-01

    By incorporating the nonempirical SCAN semilocal density functional [Sun, Ruzsinszky, and Perdew, Phys. Rev. Lett. 115, 036402 (2015)] in the underlying expression of four existing hybrid and double-hybrid models, we propose one hybrid (SCAN0) and three double-hybrid (SCAN0-DH, SCAN-QIDH, and SCAN0-2) density functionals, which are free from any fitted parameters. The SCAN-based double-hybrid functionals consistently outperform their parent SCAN semilocal functional for self-interaction probl...

  20. Self-management of oral anticoagulant therapy in two centers

    DEFF Research Database (Denmark)

    Nilsson, Hanna; Grove, E; Larsen, Torben Bjerregaard

    of Cardiology, Aarhus University Hospital, Aarhus; 3Department of Cardiology, Aalborg Hospital & Department of Health Science and Technology, Aalborg University, Aalborg, Denmark haana_86@hotmail.com Objectives: Patient-self-management (PSM) of oral anticoagulant therapy with vitamin K antagonists have...... demonstrated efficacy in randomized clinical trials. An important question remains about its clinical effectiveness. We hypothesized that implementation of PSM in everyday clinical practice could improve the quality of treatment. The aim of this study was to evaluate the effectiveness of PSM in everyday...... clinical practice. Materials and methods: A case-series study including all patients who had passed an exam in PSM in the period 1995-2012 at Aarhus University Hospital or Aalborg University Hospital, including 2200 patients and 11000 patient-years in total. The effectiveness was measured using...

  1. Two-center-multipole expansion method: application to macromolecular systems

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Yakubovich, Alexander V.; Solov'yov, Andrey V.;

    2007-01-01

    We propose a theoretical method for the calculation of the interaction energy between macromolecular systems at large distances. The method provides a linear scaling of the computing time with the system size and is considered as an alternative to the well-known fast multipole method. Its...

  2. Bounded hybrid superiority in an avian hybrid zone: effects of mate, diet, and habitat choice.

    Science.gov (United States)

    Good, T P; Ellis, J C; Annett, C A; Pierotti, R

    2000-10-01

    There has been considerable debate in the study of hybrid zones as to whether hybrids may be superior to parental types within the area of contact (bounded hybrid superiority). In birds, naturally occurring hybridization is relatively common, and hybridization within this group always involves mate choice. If hybrids are superior, females choosing heterospecific mates should be expected to show higher fitness under the conditions prevalent in the hybrid zone. Hybrid superiority under these circumstances would reduce reinforcement and thereby help to maintain the hybrid zone. To examine this issue, we studied reproductive performances of hybrids and parental species of gulls (Larus occidentalis and Larus glaucescens) at two colonies within a linear hybrid zone along the west coast of the United States. This hybrid zone contains predominantly gulls of intermediate phenotype. Previous studies indicated that hybrids were superior to one or both parental types, but provided no data on possible mechanisms that underlie this hybrid superiority. Using a hybrid index designed specifically for these species, we identified to phenotype more than 300 individuals associated with nests, including both individual males and females within 73 pairs in the central portion of the hybrid zone and 74 pairs in the northern portion of the hybrid zone. There was little evidence of assortative mating, and what little there was resulted solely because of pairings within intergrades. In the central hybrid zone, females paired with hybrid males produced larger clutches and hatched and fledged more chicks compared with females paired to western gull males. This was a result of heavy predation on eggs in sand habitat, where male western gulls established territories. In contrast, many hybrid males established territories in vegetated cover that was less vulnerable to predation. In the northern part of the hybrid zone, clutch size did not differ among pair categories, however, there were

  3. Gasoline hybrid pneumatic engine for efficient vehicle powertrain hybridization

    OpenAIRE

    Dimitrova, Zlatina; Maréchal, François

    2015-01-01

    The largest applied convertors in passenger cars are the internal combustion engines – gasoline, diesel, adapted also for operating on alternative fuels and hybrid modes. The number of components that are necessary to realize modern future propulsion system is inexorably increasing. The need for efficiency improvement of the vehicle energy system induces the search for an innovative methodology during the design process. In this article the compressed air is investigated as an innovative solu...

  4. Towards stable silicon nanoarray hybrid solar cells.

    Science.gov (United States)

    He, W W; Wu, K J; Wang, K; Shi, T F; Wu, L; Li, S X; Teng, D Y; Ye, C H

    2014-01-16

    Silicon nanoarray hybrid solar cells benefit from the ease of fabrication and the cost-effectiveness of the hybrid structure, and represent a new research focus towards the utilization of solar energy. However, hybrid solar cells composed of both inorganic and organic components suffer from the notorious stability issue, which has to be tackled before the hybrid solar cells could become a viable alternative for harvesting solar energy. Here we show that Si nanoarray/PEDOT:PSS hybrid solar cells with improved stability can be fabricated via eliminating the water inclusion in the initial formation of the heterojunction between Si nanoarray and PEDOT:PSS. The Si nanoarray hybrid solar cells are stable against rapid degradation in the atmosphere environment for several months without encapsulation. This finding paves the way towards the real-world applications of Si nanoarray hybrid solar cells.

  5. Hybrid methods for cybersecurity analysis :

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Warren Leon,; Dunlavy, Daniel M.

    2014-01-01

    Early 2010 saw a signi cant change in adversarial techniques aimed at network intrusion: a shift from malware delivered via email attachments toward the use of hidden, embedded hyperlinks to initiate sequences of downloads and interactions with web sites and network servers containing malicious software. Enterprise security groups were well poised and experienced in defending the former attacks, but the new types of attacks were larger in number, more challenging to detect, dynamic in nature, and required the development of new technologies and analytic capabilities. The Hybrid LDRD project was aimed at delivering new capabilities in large-scale data modeling and analysis to enterprise security operators and analysts and understanding the challenges of detection and prevention of emerging cybersecurity threats. Leveraging previous LDRD research e orts and capabilities in large-scale relational data analysis, large-scale discrete data analysis and visualization, and streaming data analysis, new modeling and analysis capabilities were quickly brought to bear on the problems in email phishing and spear phishing attacks in the Sandia enterprise security operational groups at the onset of the Hybrid project. As part of this project, a software development and deployment framework was created within the security analyst work ow tool sets to facilitate the delivery and testing of new capabilities as they became available, and machine learning algorithms were developed to address the challenge of dynamic threats. Furthermore, researchers from the Hybrid project were embedded in the security analyst groups for almost a full year, engaged in daily operational activities and routines, creating an atmosphere of trust and collaboration between the researchers and security personnel. The Hybrid project has altered the way that research ideas can be incorporated into the production environments of Sandias enterprise security groups, reducing time to deployment from months and

  6. Enhanced catalytic four-electron dioxygen (O2) and two-electron hydrogen peroxide (H2O2) reduction with a copper(II) complex possessing a pendant ligand pivalamido group.

    Science.gov (United States)

    Kakuda, Saya; Peterson, Ryan L; Ohkubo, Kei; Karlin, Kenneth D; Fukuzumi, Shunichi

    2013-05-01

    A copper complex, [(PV-tmpa)Cu(II)](ClO4)2 (1) [PV-tmpa = bis(pyrid-2-ylmethyl){[6-(pivalamido)pyrid-2-yl]methyl}amine], acts as a more efficient catalyst for the four-electron reduction of O2 by decamethylferrocene (Fc*) in the presence of trifluoroacetic acid (CF3COOH) in acetone as compared with the corresponding copper complex without a pivalamido group, [(tmpa)Cu(II)](ClO4)2 (2) (tmpa = tris(2-pyridylmethyl)amine). The rate constant (k(obs)) of formation of decamethylferrocenium ion (Fc*(+)) in the catalytic four-electron reduction of O2 by Fc* in the presence of a large excess CF3COOH and O2 obeyed first-order kinetics. The k(obs) value was proportional to the concentration of catalyst 1 or 2, whereas the k(obs) value remained constant irrespective of the concentration of CF3COOH or O2. This indicates that electron transfer from Fc* to 1 or 2 is the rate-determining step in the catalytic cycle of the four-electron reduction of O2 by Fc* in the presence of CF3COOH. The second-order catalytic rate constant (k(cat)) for 1 is 4 times larger than the corresponding value determined for 2. With the pivalamido group in 1 compared to 2, the Cu(II)/Cu(I) potentials are -0.23 and -0.05 V vs SCE, respectively. However, during catalytic turnover, the CF3COO(-) anion present readily binds to 2 shifting the resulting complex's redox potential to -0.35 V. The pivalamido group in 1 is found to inhibit anion binding. The overall effect is to make 1 easier to reduce (relative to 2) during catalysis, accounting for the relative k(cat) values observed. 1 is also an excellent catalyst for the two-electron two-proton reduction of H2O2 to water and is also more efficient than is 2. For both complexes, reaction rates are greater than for the overall four-electron O2-reduction to water, an important asset in the design of catalysts for the latter.

  7. One-photon two-electron processes in helium close to the double ionization threshold; Diexcitation electronique de l'helium par un photon au voisinage du seuil de double ionisation

    Energy Technology Data Exchange (ETDEWEB)

    Bouri, C

    2007-04-15

    This work presents a study of the {sup 1}P{sup 0} excited states of He that can be reached by absorption of a single photon carrying an energy close to the double ionization threshold (DIT) (79 eV). Above the DIT, these states are the double continuum states; below, they are the double excited states. These two types of states are tightly coupled to the single continuum states with or without excitation of the residual ion He{sup +}, owing to their degeneracy in energy. In a one-photon process, these states can only be formed owing to the electronic correlations in the system which must be well described to obtain quantitative good results. Our study is a part of the work which aims at a united description of all these doubly excited, ionized-excited, and double continuum states. We use the Hyperspherical R-Matrix with Semiclassical Outgoing Waves (HRM-SOW) method, initially dedicated to double photoionization studies. We extend it to extract information on the single continuum. This extension allows us to compute cross sections of single photoionization with or without excitation up to n 50 for an excess of 100 meV just above the double ionization threshold. A deep insight into this process is given by a partial waves analysis. The results obtained shed light on the key role of angular and radial correlations. The numerous data we obtain on double and single ionization allow us to establish a continuity relation between these two processes. We show that single ionization with an infinite excitation of the residual ion merges into double photoionization when the excess energy is redistributed between the two electrons. It appears that this relation is valid not only for low but also for high photon energies. Since the HRM-SOW can produce the integrated cross section for double photoionization with high accuracy in the low energy domain, we check the Wannier threshold law. The parameters extracted support strongly this threshold law, and are in good agreement with

  8. Clinical Role of Hybrid Imaging.

    Science.gov (United States)

    Hsiao, Edward M; Ali, Bilal; Dorbala, Sharmila

    2010-10-01

    Recent technological advances have fueled the growth in hybrid radionuclide and CT imaging of the heart. Noninvasive imaging studies are reliable means to diagnose coronary artery disease (CAD), stratify risk, and guide clinical management. Myocardial perfusion scintigraphy is a robust, widely available noninvasive modality for the evaluation of ischemia from known or suspected CAD. Cardiac CT (coronary artery calcium score and coronary CT angiography) has emerged as a clinically robust noninvasive anatomic imaging test, capable of rapidly diagnosing or excluding obstructive CAD. Both anatomic and functional modalities have strengths and weaknesses, and can complement each other by offering integrated structural and physiologic information. As we discuss below, in selected patients, hybrid imaging may facilitate more accurate diagnosis, risk stratification, and management in a "one-stop shop" setting.

  9. Photoelastic tomography as hybrid mechanics

    Directory of Open Access Journals (Sweden)

    Errapart A.

    2010-06-01

    Full Text Available Photoelastic tomography is a non-destructive method of 3D stress analysis. It permits determination of normal stress distribution in an arbitrary section of a 3D test object. In case of axial symmetry also the shear stress distribution can be determined directly from the measurement data. To determine also the other stress components one can use equations of the theory of elasticity. Such a combined application of experimental measurements and numerical handling of the equations of the theory of elasticity is named hybrid mechanics. It is shown that if stresses are due to external loads, the hybrid mechanics algorithm is based on the equations of equilibrium and compatibility. In the case of the measurement of the residual stress in glass the compatibility equation can not be applied. In this case a new relationship of axisymmetric thermoelasticity, the generalized sum rule can be applied.

  10. Photoelastic tomography as hybrid mechanics

    Science.gov (United States)

    Aben, H.; Ainola, L.; Errapart, A.

    2010-06-01

    Photoelastic tomography is a non-destructive method of 3D stress analysis. It permits determination of normal stress distribution in an arbitrary section of a 3D test object. In case of axial symmetry also the shear stress distribution can be determined directly from the measurement data. To determine also the other stress components one can use equations of the theory of elasticity. Such a combined application of experimental measurements and numerical handling of the equations of the theory of elasticity is named hybrid mechanics. It is shown that if stresses are due to external loads, the hybrid mechanics algorithm is based on the equations of equilibrium and compatibility. In the case of the measurement of the residual stress in glass the compatibility equation can not be applied. In this case a new relationship of axisymmetric thermoelasticity, the generalized sum rule can be applied.

  11. Atom-Light Hybrid Interferometer.

    Science.gov (United States)

    Chen, Bing; Qiu, Cheng; Chen, Shuying; Guo, Jinxian; Chen, L Q; Ou, Z Y; Zhang, Weiping

    2015-07-24

    A new type of hybrid atom-light interferometer is demonstrated with atomic Raman amplification processes replacing the beam splitting elements in a traditional interferometer. This nonconventional interferometer involves correlated optical and atomic waves in the two arms. The correlation between atoms and light developed with the Raman process makes this interferometer different from conventional interferometers with linear beam splitters. It is observed that the high-contrast interference fringes are sensitive to the optical phase via a path change as well as the atomic phase via a magnetic field change. This new atom-light correlated hybrid interferometer is a sensitive probe of the atomic internal state and should find wide applications in precision measurement and quantum control with atoms and photons.

  12. Hybrid metric-Palatini gravity

    CERN Document Server

    Capozziello, Salvatore; Koivisto, Tomi S; Lobo, Francisco S N; Olmo, Gonzalo J

    2015-01-01

    Recently, the phenomenology of f(R) gravity has been scrutinized motivated by the possibility to account for the self-accelerated cosmic expansion without invoking dark energy sources. Besides, this kind of modified gravity is capable of addressing the dynamics of several self-gravitating systems alternatively to the presence of dark matter. It has been established that both metric and Palatini versions of these theories have interesting features but also manifest severe and different downsides. A hybrid combination of theories, containing elements from both these two formalisms, turns out to be also very successful accounting for the observed phenomenology and is able to avoid some drawbacks of the original approaches. This article reviews the formulation of this hybrid metric-Palatini approach and its main achievements in passing the local tests and in applications to astrophysical and cosmological scenarios, where it provides a unified approach to the problems of dark energy and dark matter.

  13. Segmented Hybrid Gasostatic Bearing Optimization

    Directory of Open Access Journals (Sweden)

    Prodan Nikolay Vasilevich

    2014-07-01

    Full Text Available The purpose of research-development of methods of numerical optimization rotatable support pads gasostatic hybrid bearing. In the world‘s aerospace engineering the gas-dynamic bearings are currently most common. They are characterized by the supporting layer of different designs, which ensures the workability of the rotors during starts and stops. The main problem of this bearing type, apart from the construction complexity is the wear of this supporting layer. Gas-static bearing has no such defect, since there is no physical contact between solid surfaces. This study presents the results of the hybrid bearing’s calculation, combining both technologies. The slotted nozzle of non-conventional shape that mirrors the solution of Reynolds equation’s isoline is studied. The dependences of the main parameters on the speed of the shaft’s rotation are discussed. The aerodynamic resistance of pads for different regimes of operation is investigated.

  14. Hybrid power plants; Thermische Hybridkraftwerke

    Energy Technology Data Exchange (ETDEWEB)

    Tuschy, I. [ALSTOM Power Support, Mannheim (Germany). Bereiche Forschung und Entwicklung/Ingenieurdienstleistungen; Franke, U. [Fachhochschule Flensburg (Germany). Thermodynamik

    2002-07-01

    New German laws concerning the use of biomass and other renewable energy sources have improved the conditions for power generation with renewable energies. A promising alternative to common small-scale (combined-heat-and-) power plants could be found in so-called hybrid power plants which use renewable energies and fossil fuels in combination. A thermodynamic process analysis shows how to determine the renewable energies' portion of a hybrid power plant's total output. [German] Mit den veraenderten gesetzlichen Rahmenbedingungen erhoeht sich die Motivation, regenerative Energiequellen zur Stromerzeugung zu nutzen. Neben dem exklusiven Einsatz in kleineren (Heiz-) Kraftwerken bietet sich die gemeinsame Nutzung mit fossilen Energietraegern in sogenannten Hybridkraftwerken an. Hier stellt sich die Frage, wie der Anteil der regenerativen Energien an der Gesamt-Stromproduktion des Hybridkraftwerkes zu ermitteln ist. Eine thermodynamische Prozessanalyse kann darueber Aufschluss geben.

  15. Hybrid Maritime Satellite Communication Antenna

    DEFF Research Database (Denmark)

    Smith, Thomas Gunst

    Hybrid antennas for a maritime satellite communication terminal with simultaneous operation at L- and Ka-band have been investigated. The frequency bands of interest are 1; 525:0 1; 660:5 MHz (RX+TX, RHCP), 19:7 20:2 (RX, LHCP) and 29:5 30:0 GHz (TX, RHCP), which are all part of the Inmarsat BGAN...

  16. Performance of hybrid photovoltaic collector

    OpenAIRE

    Garbisu Eugui, Josu

    2010-01-01

    The aim of the present project is the study of the performance of a combined photovoltaic-thermal plant, called also hybrid system, located in south Italy, evaluating the efficiency of the photovoltaic and thermal systems and the advantage respect to the two single plants (photovoltaic and thermal ). This research project has two objectives fundamentals of efficiency improvement energy from solar photovoltaic panels. On one hand, increase photovoltaic efficiency, at the same time an...

  17. Hybrid Systems: Computation and Control.

    Science.gov (United States)

    2007-11-02

    elbow) and a pinned first joint (shoul- der) (see Figure 2); it is termed an underactuated system since it is a mechanical system with fewer...Montreal, PQ, Canada, 1998. [10] M. W. Spong. Partial feedback linearization of underactuated mechanical systems . In Proceedings, IROS󈨢, pages 314-321...control mechanism and search for optimal combinations of control variables. Besides the nonlinear and hybrid nature of powertrain systems , hardware

  18. Hybrid and hierarchical composite materials

    CERN Document Server

    Kim, Chang-Soo; Sano, Tomoko

    2015-01-01

    This book addresses a broad spectrum of areas in both hybrid materials and hierarchical composites, including recent development of processing technologies, structural designs, modern computer simulation techniques, and the relationships between the processing-structure-property-performance. Each topic is introduced at length with numerous  and detailed examples and over 150 illustrations.   In addition, the authors present a method of categorizing these materials, so that representative examples of all material classes are discussed.

  19. Hybrid optical acoustic seafloor mapping

    Science.gov (United States)

    Inglis, Gabrielle

    The oceanographic research and industrial communities have a persistent demand for detailed three dimensional sea floor maps which convey both shape and texture. Such data products are used for archeology, geology, ship inspection, biology, and habitat classification. There are a variety of sensing modalities and processing techniques available to produce these maps and each have their own potential benefits and related challenges. Multibeam sonar and stereo vision are such two sensors with complementary strengths making them ideally suited for data fusion. Data fusion approaches however, have seen only limited application to underwater mapping and there are no established methods for creating hybrid, 3D reconstructions from two underwater sensing modalities. This thesis develops a processing pipeline to synthesize hybrid maps from multi-modal survey data. It is helpful to think of this processing pipeline as having two distinct phases: Navigation Refinement and Map Construction. This thesis extends existing work in underwater navigation refinement by incorporating methods which increase measurement consistency between both multibeam and camera. The result is a self consistent 3D point cloud comprised of camera and multibeam measurements. In map construction phase, a subset of the multi-modal point cloud retaining the best characteristics of each sensor is selected to be part of the final map. To quantify the desired traits of a map several characteristics of a useful map are distilled into specific criteria. The different ways that hybrid maps can address these criteria provides justification for producing them as an alternative to current methodologies. The processing pipeline implements multi-modal data fusion and outlier rejection with emphasis on different aspects of map fidelity. The resulting point cloud is evaluated in terms of how well it addresses the map criteria. The final hybrid maps retain the strengths of both sensors and show significant improvement

  20. Complex hybrid inflation and baryogenesis.

    Science.gov (United States)

    Delepine, David; Martínez, Carlos; Ureña-López, L Arturo

    2007-04-20

    We propose a hybrid inflation model with a complex waterfall field which contains an interaction term that breaks the U(1) global symmetry associated with the waterfall field charge. We show that the asymmetric evolution of the real and imaginary parts of the complex field during the phase transition at the end of inflation translates into a charge asymmetry. The latter strongly depends on the vacuum expectation value of the waterfall field, which is well constrained by diverse cosmological observations.

  1. Hybrid Tower, Designing Soft Structures

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette; Tamke, Martin; Holden Deleuran, Anders;

    2015-01-01

    predictions about the inherent interdependency and material dependent performance of the hybrid structure and (2) the inter-scalar design strategies for specification and fabrication. The first investigation focuses on the design pipelines developed between the implementation of realtime physics...... (membrane reinforcement strategy) and micro scale (design of bespoke textile membrane). The paper concludes with a post construction analysis. Comparing structural and environmental data, the predicted and the actual performance of tower are evaluated and discussed....

  2. CERN manufactured hybrid photon detectors

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    These hybrid photon detectors (HPDs) produce an electric signal from a single photon. An electron is liberated from a photocathode and accelerated to a silicon pixel array allowing the location of the photon on the cathode to be recorded. The electronics and optics for these devices have been developed in close collaboration with industry. HPDs have potential for further use in astrophysics and medical imaging.

  3. Hybrid metric-Palatini stars

    CERN Document Server

    Danila, Bogdan; Lobo, Francisco S N; Mak, M K

    2016-01-01

    We consider the internal structure and the physical properties of specific classes of neutron, quark and Bose-Einstein Condensate stars in the hybrid metric-Palatini gravity theory, which is a combination of the metric and Palatini $f(R)$ formalisms. The theory is very successful in accounting for the observed phenomenology, since it unifies local constraints at the Solar System level and the late-time cosmic acceleration, even if the scalar field is very light. We derive the equilibrium equations for a spherically symmetric configuration (mass continuity and Tolman-Oppenheimer-Volkoff) in the framework of hybrid metric-Palatini theory, and we investigate their solutions numerically for different equations of state of neutron and quark matter, by adopting for the scalar field potential a Higgs-type form. Stellar models, described by the stiff fluid, radiation-like, the bag model and the Bose-Einstein Condensate equations of state are explicitly constructed in both General Relativity and hybrid metric-Palatini...

  4. Electroactive functional hybrid layered nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Destri, Giovanni Li; Torrisi, Vanna; Marletta, Giovanni [Laboratory for Molecular Surfaces and Nanotechnology (LAMSUN) - University of Catania and CSGI - Catania (Italy)

    2012-07-11

    Two methodologies to build new nanostructured hybrid layered nanocomposites are presented. The first one involves the preparation of hybrid metal/polymer nanolayers (NLs) by combining two monolayer preparation techniques: Horizontal Precipitation Langmuir Blodgett method (HP-ML), for copolymer monolayers and sputter deposition technique, for Au NLs deposition. The second methodology is aimed to prepare regular arrays of nanopores, with diameter ranging between 40-100 nm, in ultra-thin films of electroactive polymers, to obtain embedded regular arrays of nanopores filled by a further electroactive organic component. The produced hybrid MLs have been characterized by means of X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and Grazing Incidence X-ray Diffraction (GI-XRD). In the first case, current-voltage (I-V) measurements demonstrate that the multilayers exhibit a bipolar conduction behaviour (electrons and holes carriers), with a peculiar transition in the nature of the majority carriers (from holes to electrons) above a threshold number of bilayers. In the second case, it is found that the degree of pore filling, as well as the polymer crystallinity can be easily modulated, prompting the tuning of the photoresponse of the nanocomposites.

  5. Gravity localization on hybrid branes

    Energy Technology Data Exchange (ETDEWEB)

    Veras, D.F.S., E-mail: franklin@fisica.ufc.br [Universidade Federal do Ceará (UFC), Departamento de Física, Campus do Pici, Caixa Postal 6030, 60455-760, Fortaleza, Ceará (Brazil); Cruz, W.T., E-mail: wilamicruz@gmail.com [Instituto Federal de Educação, Ciência e Tecnologia do Ceará (IFCE), Campus Juazeiro do Norte, 63040-540 Juazeiro do Norte, Ceará (Brazil); Maluf, R.V., E-mail: r.v.maluf@fisica.ufc.br [Universidade Federal do Ceará (UFC), Departamento de Física, Campus do Pici, Caixa Postal 6030, 60455-760, Fortaleza, Ceará (Brazil); Almeida, C.A.S., E-mail: carlos@fisica.ufc.br [Universidade Federal do Ceará (UFC), Departamento de Física, Campus do Pici, Caixa Postal 6030, 60455-760, Fortaleza, Ceará (Brazil)

    2016-03-10

    This work deals with gravity localization on codimension-1 brane worlds engendered by compacton-like kinks, the so-called hybrid branes. In such scenarios, the thin brane behavior is manifested when the extra dimension is outside the compact domain, where the energy density is non-trivial, instead of asymptotically as in the usual thick brane models. The zero mode is trapped in the brane, as required. The massive modes, although not localized in the brane, have important phenomenological implications such as corrections to the Newton's law. We study such corrections in the usual thick domain wall and in the hybrid brane scenarios. By means of suitable numerical methods, we attain the mass spectrum for the graviton and the corresponding wavefunctions. The spectra possess the usual linearly increasing behavior from the Kaluza–Klein theories. Further, we show that the 4D gravitational force is slightly increased at short distances. The first eigenstate contributes highly for the correction to the Newton's law. The subsequent normalized solutions have diminishing contributions. Moreover, we find out that the phenomenology of the hybrid brane is not different from the usual thick domain wall. The use of numerical techniques for solving the equations of the massive modes is useful for matching possible phenomenological measurements in the gravitational law as a probe to warped extra dimensions.

  6. Gravity localization on hybrid branes

    Science.gov (United States)

    Veras, D. F. S.; Cruz, W. T.; Maluf, R. V.; Almeida, C. A. S.

    2016-03-01

    This work deals with gravity localization on codimension-1 brane worlds engendered by compacton-like kinks, the so-called hybrid branes. In such scenarios, the thin brane behavior is manifested when the extra dimension is outside the compact domain, where the energy density is non-trivial, instead of asymptotically as in the usual thick brane models. The zero mode is trapped in the brane, as required. The massive modes, although not localized in the brane, have important phenomenological implications such as corrections to the Newton's law. We study such corrections in the usual thick domain wall and in the hybrid brane scenarios. By means of suitable numerical methods, we attain the mass spectrum for the graviton and the corresponding wavefunctions. The spectra possess the usual linearly increasing behavior from the Kaluza-Klein theories. Further, we show that the 4D gravitational force is slightly increased at short distances. The first eigenstate contributes highly for the correction to the Newton's law. The subsequent normalized solutions have diminishing contributions. Moreover, we find out that the phenomenology of the hybrid brane is not different from the usual thick domain wall. The use of numerical techniques for solving the equations of the massive modes is useful for matching possible phenomenological measurements in the gravitational law as a probe to warped extra dimensions.

  7. The plus-hybrid effect on the grain yield of two ZP maize hybrids

    Directory of Open Access Journals (Sweden)

    Božinović Sofija

    2010-01-01

    Full Text Available The combined effect of cytoplasmic male sterility and xenia on maize hybrid traits is referred to as the plus-hybrid effect. Two studied ZP hybrids differently responded to this effect for grain yield. All plus-hybrid combinations of the firstly observed hybrid had a higher yield than their fertile counterparts, but not significantly, while only one combination of the second hybrid positively responded, also without statistical significance. It seems that the observed effect mostly depended on the genotype of the female component.

  8. Hybrid metric-Palatini stars

    Science.gov (United States)

    Danilǎ, Bogdan; Harko, Tiberiu; Lobo, Francisco S. N.; Mak, M. K.

    2017-02-01

    We consider the internal structure and the physical properties of specific classes of neutron, quark and Bose-Einstein condensate stars in the recently proposed hybrid metric-Palatini gravity theory, which is a combination of the metric and Palatini f (R ) formalisms. It turns out that the theory is very successful in accounting for the observed phenomenology, since it unifies local constraints at the Solar System level and the late-time cosmic acceleration, even if the scalar field is very light. In this paper, we derive the equilibrium equations for a spherically symmetric configuration (mass continuity and Tolman-Oppenheimer-Volkoff) in the framework of the scalar-tensor representation of the hybrid metric-Palatini theory, and we investigate their solutions numerically for different equations of state of neutron and quark matter, by adopting for the scalar field potential a Higgs-type form. It turns out that the scalar-tensor definition of the potential can be represented as an Clairaut differential equation, and provides an explicit form for f (R ) given by f (R )˜R +Λeff, where Λeff is an effective cosmological constant. Furthermore, stellar models, described by the stiff fluid, radiation-like, bag model and the Bose-Einstein condensate equations of state are explicitly constructed in both general relativity and hybrid metric-Palatini gravity, thus allowing an in-depth comparison between the predictions of these two gravitational theories. As a general result it turns out that for all the considered equations of state, hybrid gravity stars are more massive than their general relativistic counterparts. Furthermore, two classes of stellar models corresponding to two particular choices of the functional form of the scalar field (constant value, and logarithmic form, respectively) are also investigated. Interestingly enough, in the case of a constant scalar field the equation of state of the matter takes the form of the bag model equation of state describing

  9. A "Hybrid" Approach for Synthesizing Optimal Controllers of Hybrid Systems

    DEFF Research Database (Denmark)

    Zhao, Hengjun; Zhan, Naijun; Kapur, Deepak

    2012-01-01

    We propose an approach to reduce the optimal controller synthesis problem of hybrid systems to quantifier elimination; furthermore, we also show how to combine quantifier elimination with numerical computation in order to make it more scalable but at the same time, keep arising errors due...... to discretization manageable and within bounds. A major advantage of our approach is not only that it avoids errors due to numerical computation, but it also gives a better optimal controller. In order to illustrate our approach, we use the real industrial example of an oil pump provided by the German company HYDAC...

  10. Hybrid Airy Plasmons with Dynamically Steerable Trajectories

    CERN Document Server

    Li, Rujiang; Lin, Xiao; Wang, Huaping; Xu, Zhiwei; Chen, Hongsheng

    2016-01-01

    With the intriguing properties of diffraction-free, self-accelerating, and self-healing, Airy plasmons are promising to be used in the trapping, transporting, and sorting of micro-objects, imaging, and chip scale signal processing. However, the high dissipative loss and the lack of dynamical steerability restrict the implementation of Airy plasmons in these applications. Here we reveal the hybrid Airy plasmons for the first time by taking a hybrid graphene-based plasmonic waveguide in the terahertz (THz) domain as an example. Due to the coupling between an optical mode and a plasmonic mode, the hybrid Airy plasmons can have large propagation lengths and effective transverse deflections, where the transverse waveguide confinements are governed by the hybrid modes with moderate quality factors. Meanwhile, the propagation trajectories of hybrid Airy plasmons are dynamically steerable by changing the chemical potential of graphene. These hybrid Airy plasmons may promote the further discovery of non-diffracting be...

  11. Hybrid Airy plasmons with dynamically steerable trajectories.

    Science.gov (United States)

    Li, Rujiang; Imran, Muhammad; Lin, Xiao; Wang, Huaping; Xu, Zhiwei; Chen, Hongsheng

    2017-01-26

    With their intriguing diffraction-free, self-accelerating, and self-healing properties, Airy plasmons show promise for use in the trapping, transporting, and sorting of micro-objects, imaging, and chip scale signal processing. However, high dissipative loss and lack of dynamical steerability restrict the implementation of Airy plasmons in these applications. Here we reveal hybrid Airy plasmons for the first time by taking a hybrid graphene-based plasmonic waveguide in the terahertz (THz) domain as an example. Due to coupling between optical modes and plasmonic modes, the hybrid Airy plasmons can have large propagation lengths and effective transverse deflections, where the transverse waveguide confinements are governed by the hybrid modes with moderate quality factors. Meanwhile, the propagation trajectories of the hybrid Airy plasmons are dynamically steerable by changing the chemical potential of graphene. These hybrid Airy plasmons may promote the further discovery of non-diffracting beams along with the emerging developments of optical tweezers and tractor beams.

  12. A Hybrid Architecture Approach for Quantum Algorithms

    Directory of Open Access Journals (Sweden)

    Mohammad R.S. Aghaei

    2009-01-01

    Full Text Available Problem statement: In this study, a general plan of hybrid architecture for quantum algorithms is proposed. Approach: Analysis of the quantum algorithms shows that these algorithms were hybrid with two parts. First, the relationship of classical and quantum parts of the hybrid algorithms was extracted. Then a general plan of hybrid structure was designed. Results: This plan was illustrated the hybrid architecture and the relationship of classical and quantum parts of the algorithms. This general plan was used to increase implementation performance of quantum algorithms. Conclusion/Recommendations: Moreover, simulation results of quantum algorithms on the hybrid architecture proved that quantum algorithms can be implemented on the general plan as well.

  13. Hybrid soft computing approaches research and applications

    CERN Document Server

    Dutta, Paramartha; Chakraborty, Susanta

    2016-01-01

    The book provides a platform for dealing with the flaws and failings of the soft computing paradigm through different manifestations. The different chapters highlight the necessity of the hybrid soft computing methodology in general with emphasis on several application perspectives in particular. Typical examples include (a) Study of Economic Load Dispatch by Various Hybrid Optimization Techniques, (b) An Application of Color Magnetic Resonance Brain Image Segmentation by ParaOptiMUSIG activation Function, (c) Hybrid Rough-PSO Approach in Remote Sensing Imagery Analysis,  (d) A Study and Analysis of Hybrid Intelligent Techniques for Breast Cancer Detection using Breast Thermograms, and (e) Hybridization of 2D-3D Images for Human Face Recognition. The elaborate findings of the chapters enhance the exhibition of the hybrid soft computing paradigm in the field of intelligent computing.

  14. Flight Testing of Hybrid Powered Vehicles

    Science.gov (United States)

    Story, George; Arves, Joe

    2006-01-01

    Hybrid Rocket powered vehicles have had a limited number of flights. Most recently in 2004, Scaled Composites had a successful orbital trajectory that put a private vehicle twice to over 62 miles high, the edge of space to win the X-Prize. This endeavor man rates a hybrid system. Hybrids have also been used in a number of one time launch attempts - SET-1, HYSR, HPDP. Hybrids have also been developed for use and flown in target drones. This chapter discusses various flight-test programs that have been conducted, hybrid vehicles that are in development, other hybrid vehicles that have been proposed and some strap-on applications have also been examined.

  15. [Hybridization of crucian carp, Carassius carassius (Linnaeus, 1758), in Ukrainian reservoirs and genetic structure of hybrids].

    Science.gov (United States)

    Mezhzheryn, S V; Kokodyĭĭ, S V; Kulysh, A V; Verlat'iĭĭ, D B; Fedorenko, L V

    2012-01-01

    Hybridization of crucian carps Carassius carassius in polyspecific crucian populations of reservoirs of Ukraine and genetic structure of the hybrids were investigated using biochemical gene marking and cytometric procedure. The fact of wide hybridization between C. auratus and C. carassius was proved to be true by large number of hybrids which can form populations consisting only from hybrid individuals. Hybrids C. auratus x C. carassius were diploid, tryploid and in exceptional cases tetraploid; females and males which most likely breed by hybridogenesis. Besides, some clonal hybrids C. carassius x C. gibelio-1 appearing as tetraploid females, and one triploid female C. carassius x Tinca tinca were revealed. It is supported that hybridization of alien C. auratus with endemic C. carassius became one of mechanisms of replacement and depressions of populations of the last.

  16. Parallel Hybrid Vehicle Optimal Storage System

    Science.gov (United States)

    Bloomfield, Aaron P.

    2009-01-01

    A paper reports the results of a Hybrid Diesel Vehicle Project focused on a parallel hybrid configuration suitable for diesel-powered, medium-sized, commercial vehicles commonly used for parcel delivery and shuttle buses, as the missions of these types of vehicles require frequent stops. During these stops, electric hybridization can effectively recover the vehicle's kinetic energy during the deceleration, store it onboard, and then use that energy to assist in the subsequent acceleration.

  17. Hybrid and Plug-in Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-05-20

    Hybrid and plug-in electric vehicles use electricity either as their primary fuel or to improve the efficiency of conventional vehicle designs. This new generation of vehicles, often called electric drive vehicles, can be divided into three categories: hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles(PHEVs), and all-electric vehicles (EVs). Together, they have great potential to reduce U.S. petroleum use.

  18. Genomic Prediction of Barley Hybrid Performance

    Directory of Open Access Journals (Sweden)

    Norman Philipp

    2016-07-01

    Full Text Available Hybrid breeding in barley ( L. offers great opportunities to accelerate the rate of genetic improvement and to boost yield stability. A crucial requirement consists of the efficient selection of superior hybrid combinations. We used comprehensive phenotypic and genomic data from a commercial breeding program with the goal of examining the potential to predict the hybrid performances. The phenotypic data were comprised of replicated grain yield trials for 385 two-way and 408 three-way hybrids evaluated in up to 47 environments. The parental lines were genotyped using a 3k single nucleotide polymorphism (SNP array based on an Illumina Infinium assay. We implemented ridge regression best linear unbiased prediction modeling for additive and dominance effects and evaluated the prediction ability using five-fold cross validations. The prediction ability of hybrid performances based on general combining ability (GCA effects was moderate, amounting to 0.56 and 0.48 for two- and three-way hybrids, respectively. The potential of GCA-based hybrid prediction requires that both parental components have been evaluated in a hybrid background. This is not necessary for genomic prediction for which we also observed moderate cross-validated prediction abilities of 0.51 and 0.58 for two- and three-way hybrids, respectively. This exemplifies the potential of genomic prediction in hybrid barley. Interestingly, prediction ability using the two-way hybrids as training population and the three-way hybrids as test population or vice versa was low, presumably, because of the different genetic makeup of the parental source populations. Consequently, further research is needed to optimize genomic prediction approaches combining different source populations in barley.

  19. Hybrid synchronization of hyperchaotic Lu system

    Indian Academy of Sciences (India)

    K Sebastian Sudheer; M Sabir

    2009-10-01

    In this paper, we study the hybrid synchronization between two identical hyperchaotic Lu systems. Hybrid synchronization of hyperchaotic Lu system is achieved through synchronization of two pairs of states and anti-synchronization of the other two pairs of states. Active controls are designed to achieve hybrid synchronization between drive and response systems using the sum and difference of relevant variables of the chaotic systems. Numerical simulations are presented to evaluate the analysis and effectiveness of the controllers.

  20. Heavy Duty Diesel Truck and Bus Hybrid Powertrain Study

    Science.gov (United States)

    2012-03-01

    include utility boom trucks and beverage haulers. Eaton Corp. manufactures a parallel hybrid-electric drivetrain that is used by many of the truck...Original Equipment Manufacturers (OEMs). Most of the hybrid buses use series hybrid-electric drivetrains , and key manufacturers are BAE Systems, ISE...Competing Alternatives to Diesel-Electric Hybrid Powertrains ............................................ 153 6.1 Hydraulic Hybrid Drivetrains

  1. Nanostructured organic and hybrid solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Weickert, Jonas; Dunbar, Ricky B.; Hesse, Holger C.; Wiedemann, Wolfgang; Schmidt-Mende, Lukas [Department of Physics and Center for NanoScience (CeNS), Ludwig-Maximilians University (LMU) Munich, Amalienstr. 54, 80799 Munich (Germany)

    2011-04-26

    This progress report highlights recent developments in nanostructured organic and hybrid solar cells. The authors discuss novel approaches to control the film morphology in fully organic solar cells and the design of nanostructured hybrid solar cells. The motivation and recent results concerning fabrication and effects on device physics are emphasized. The aim of this review is not to give a summary of all recent results in organic and hybrid solar cells, but rather to focus on the fabrication, device physics, and light trapping properties of nanostructured organic and hybrid devices. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Cluster Tree Based Hybrid Document Similarity Measure

    Directory of Open Access Journals (Sweden)

    M. Varshana Devi

    2015-10-01

    Full Text Available hybrid similarity measure is established to measure the hybrid similarity. In cluster tree, the hybrid similarity measure can be calculated for the random data even it may not be the co-occurred and generate different views. Different views of tree can be combined and choose the one which is significant in cost. A method is proposed to combine the multiple views. Multiple views are represented by different distance measures into a single cluster. Comparing the cluster tree based hybrid similarity with the traditional statistical methods it gives the better feasibility for intelligent based search. It helps in improving the dimensionality reduction and semantic analysis.

  3. Organic/inorganic hybrid coatings for anticorrosion

    Science.gov (United States)

    He, Zhouying

    Compared to organic coatings, organic-inorganic hybrid coatings can potentially improve the anticorrosion performance. The organic phase provides the excellent mechaincal and barrier properties while the inorganic phase acts as an adhesion promoter and corrosion inhibitor. Despite that many studies on alkoxylsilane-based hybrid coatings have been developed and studied, their weatherability and anticorrosion performance has been rarely evaluated. On the other hand, organic-inorganic hybrid coatings based on mixed sol-gel precursors have received much less attention compared to alkoxylsilane-based hybrid coatings. In the first part, polyurethane hybrid coatings with a unique hybrid crosslinked structure as an improved unicoat were successfully prepared. The effect of polyesters on physical properties of the hybrid coatings was studied. Polyurethane coatings derived from cycloaliphatic polyester show comparable properties than those derived from the commercially viable aromatic polyester. Introducing the polysiloxane part into the polyurethane coatings enhanced the crosslinking density, Tg, mechanical properties, and general coating properties. The increased adhesion between the hybrid coating and the substrate make the hybrid coating a good candidate for anticorrosion application, which is shown by electrochemical impedance spectroscopy (EIS). The degradation mechanism of the polyurethane/polysiloxane hybrid coatings under various weathering conditions was shown to be the scission of the urethane and ester groups in the organic phase along with reorganizing and rearranging of the inorganic phase. The anticorrosion performance of the cycloaliphatic hybrid was much better than that of aromatic based hybrid under outdoor weathering based on visual observation and EIS analysis. Acid undercutting is an issue for TEOS based hybrid coating. In the second part, design of experiments (DOEs) was used to statistically investigate on the effect of sol-gel precursors. The

  4. Trends in the Development of Hybrid Drives

    National Research Council Canada - National Science Library

    Josef Morkus

    2016-01-01

    .... This paper deals with the growth in sales of vehicles with hybrid propulsion, the directions of their technological development, new solutions for transmission systems, the capacity and location...

  5. Consensus of Hybrid Multi-Agent Systems.

    Science.gov (United States)

    Zheng, Yuanshi; Ma, Jingying; Wang, Long

    2017-01-27

    In this brief, we consider the consensus problem of hybrid multiagent systems. First, the hybrid multiagent system is proposed, which is composed of continuous-time and discrete-time dynamic agents. Then, three kinds of consensus protocols are presented for the hybrid multiagent system. The analysis tool developed in this brief is based on the matrix theory and graph theory. With different restrictions of the sampling period, some necessary and sufficient conditions are established for solving the consensus of the hybrid multiagent system. The consensus states are also obtained under different protocols. Finally, simulation examples are provided to demonstrate the effectiveness of our theoretical results.

  6. Hybrid slab-microchannel gel electrophoresis system

    Science.gov (United States)

    Balch, Joseph W.; Carrano, Anthony V.; Davidson, James C.; Koo, Jackson C.

    1998-01-01

    A hybrid slab-microchannel gel electrophoresis system. The hybrid system permits the fabrication of isolated microchannels for biomolecule separations without imposing the constraint of a totally sealed system. The hybrid system is reusable and ultimately much simpler and less costly to manufacture than a closed channel plate system. The hybrid system incorporates a microslab portion of the separation medium above the microchannels, thus at least substantially reducing the possibility of non-uniform field distribution and breakdown due to uncontrollable leakage. A microslab of the sieving matrix is built into the system by using plastic spacer materials and is used to uniformly couple the top plate with the bottom microchannel plate.

  7. Development of a Hybrid Photopolymer for Stereolithography

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    New liquid free radical-cationic hybrid photopolymer, consisting of acrylate-based photocurable resin and epoxy-based photosensitive resin for stereolithography by UV laser was developed.The experiment results indicated that the hybrid photopolymer exhibits advantages of both the acrylate- based photosensitive resin and the epoxy- based photosensitive polymer contained in the hybrid system with relatively high photospeed and low linear shrinkage.Stereolithography parts without obvious distortion were built on the stereolithography apparatus HRPLAI from this hybrid resin successfully and efficiently.

  8. On Hybrid and mixed finite element methods

    Science.gov (United States)

    Pian, T. H. H.

    1981-01-01

    Three versions of the assumed stress hybrid model in finite element methods and the corresponding variational principles for the formulation are presented. Examples of rank deficiency for stiffness matrices by the hybrid stress model are given and their corresponding kinematic deformation modes are identified. A discussion of the derivation of general semi-Loof elements for plates and shells by the hybrid stress method is given. It is shown that the equilibrium model by Fraeijs de Veubeke can be derived by the approach of the hybrid stress model as a special case of semi-Loof elements.

  9. Hybrid Dynamical Systems Modeling, Stability, and Robustness

    CERN Document Server

    Goebel, Rafal; Teel, Andrew R

    2012-01-01

    Hybrid dynamical systems exhibit continuous and instantaneous changes, having features of continuous-time and discrete-time dynamical systems. Filled with a wealth of examples to illustrate concepts, this book presents a complete theory of robust asymptotic stability for hybrid dynamical systems that is applicable to the design of hybrid control algorithms--algorithms that feature logic, timers, or combinations of digital and analog components. With the tools of modern mathematical analysis, Hybrid Dynamical Systems unifies and generalizes earlier developments in continuous-time and discret

  10. Techno-economic comparison of series hybrid, plug-in hybrid, fuel cell and regular cars

    NARCIS (Netherlands)

    van Vliet, O.P.R.|info:eu-repo/dai/nl/288519361; Kruithof, T.; Turkenburg, W.C.|info:eu-repo/dai/nl/073416355; Faaij, A.P.C.|info:eu-repo/dai/nl/10685903X

    2010-01-01

    We examine the competitiveness of series hybrid compared to fuel cell, parallel hybrid, and regular cars. We use public domain data to determine efficiency, fuel consumption, total costs of ownership and greenhouse gas emissions resulting from drivetrain choices. The series hybrid drivetrain can be

  11. Techno-economic comparison of series hybrid, plug-in hybrid, fuel cell and regular cars

    NARCIS (Netherlands)

    van Vliet, O.P.R.; Kruithof, T.; Turkenburg, W.C.; Faaij, A.P.C.

    2010-01-01

    We examine the competitiveness of series hybrid compared to fuel cell, parallel hybrid, and regular cars. We use public domain data to determine efficiency, fuel consumption, total costs of ownership and greenhouse gas emissions resulting from drivetrain choices. The series hybrid drivetrain can be

  12. Hybrid-Source Impedance Networks

    DEFF Research Database (Denmark)

    Li, Ding; Gao, Feng; Loh, Poh Chiang;

    2010-01-01

    the cascaded networks would have a higher output voltage gain and other unique advantages that currently have not been investigated yet. It is anticipated that these advantages would help the formed inverters find applications in photovoltaic and other renewable systems, where a high voltage gain is usually......Hybrid-source impedance networks have attracted attention among researchers because of their flexibility in performing buck-boost energy conversion. To date, three distinct types of impedance networks can be summarized for implementing voltage-type inverters with another three types summarized...

  13. Essentialism, hybridism and cultural critique

    DEFF Research Database (Denmark)

    Frello, Birgitta

    2007-01-01

    Transgression concepts - such as ‘hybridity', ‘diaspora', ‘creolization', ‘transculturalization' and ‘syncretism' - have to an increasing extent become key concepts in various attempts at escaping the problems of suppression and exclusion involved in notions of purity - be it the purity of race......, culture or whatever. The purpose of focusing on concepts of transgression is usually to try to develop conceptual spaces within which it is possible to grasp and to study cultural identity without resorting to cultural essentialism. These attempts open up new possibilities but also new problems - e...

  14. Hybrid winding concept for toroids

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold

    2013-01-01

    and placement machinery. This opens up the possibility for both an automated manufacturing process and an automated production process of toroidal magnetics such as power inductors, filtering inductors, air core inductors, transformers etc. Both the proposed hybrid and the common wire wound winding...... implementation is simulated using finite element modeling and the DC and AC resistance of the inductors are verified with experimental measurements on prototypes. It is found that commercial available layer thickness of printed circuit boards is a bottleneck for high power applications. Furthermore, the winding...

  15. Coordinated hybrid automatic repeat request

    KAUST Repository

    Makki, Behrooz

    2014-11-01

    We develop a coordinated hybrid automatic repeat request (HARQ) approach. With the proposed scheme, if a user message is correctly decoded in the first HARQ rounds, its spectrum is allocated to other users, to improve the network outage probability and the users\\' fairness. The results, which are obtained for single- and multiple-antenna setups, demonstrate the efficiency of the proposed approach in different conditions. For instance, with a maximum of M retransmissions and single transmit/receive antennas, the diversity gain of a user increases from M to (J+1)(M-1)+1 where J is the number of users helping that user.

  16. Hydrostatic and hybrid bearing design

    CERN Document Server

    Rowe, W B

    1983-01-01

    Hydrostatic and Hybrid Bearing Design is a 15-chapter book that focuses on the bearing design and testing. This book first describes the application of hydrostatic bearings, as well as the device pressure, flow, force, power, and temperature. Subsequent chapters discuss the load and flow rate of thrust pads; circuit design, flow control, load, and stiffness; and the basis of the design procedures and selection of tolerances. The specific types of bearings, their design, dynamics, and experimental methods and testing are also shown. This book will be very valuable to students of engineering des

  17. IMPULSE CONTROL HYBRID ELECTRICAL SYSTEM

    Directory of Open Access Journals (Sweden)

    A. A. Lobaty

    2016-01-01

    Full Text Available This paper extends the recently introduced approach for modeling and solving the optimal control problem of fixedswitched mode DC-DC power converter. DCDC converters are a class of electric power circuits that used extensively in regulated DC power supplies, DC motor drives of different types, in Photovoltaic Station energy conversion and other applications due to its advantageous features in terms of size, weight and reliable performance. The main problem in controlling this type converters is in their hybrid nature as the switched circuit topology entails different modes of operation, each of it with its own associated linear continuous-time dynamics.This paper analyses the modeling and controller synthesis of the fixed-frequency buck DC-DC converter, in which the transistor switch is operated by a pulse sequence with constant frequency. In this case the regulation of the DC component of the output voltage is via the duty cycle. The optimization of the control system is based on the formation of the control signal at the output.It is proposed to solve the problem of optimal control of a hybrid system based on the formation of the control signal at the output of the controller, which minimizes a given functional integral quality, which is regarded as a linear quadratic Letov-Kalman functional. Search method of optimal control depends on the type of mathematical model of control object. In this case, we consider a linear deterministic model of the control system, which is common for the majority of hybrid electrical systems. For this formulation of the optimal control problem of search is a problem of analytical design of optimal controller, which has the analytical solution.As an example of the hybrid system is considered a step-down switching DC-DC converter, which is widely used in various electrical systems: as an uninterruptible power supply, battery charger for electric vehicles, the inverter in solar photovoltaic power plants.. A

  18. Hybrid Model of Content Extraction

    DEFF Research Database (Denmark)

    Qureshi, Pir Abdul Rasool; Memon, Nasrullah

    2012-01-01

    We present a hybrid model for content extraction from HTML documents. The model operates on Document Object Model (DOM) tree of the corresponding HTML document. It evaluates each tree node and associated statistical features like link density and text distribution across the node to predict...... model outperformed other existing content extraction models. We present a browser based implementation of the proposed model as proof of concept and compare the implementation strategy with various state of art implementations. We also discuss various applications of the proposed model with special...

  19. Hybrid Chernoff Tau-Leap

    KAUST Repository

    Moraes, Alvaro

    2014-01-06

    Markovian pure jump processes can model many phenomena, e.g. chemical reactions at molecular level, protein transcription and translation, spread of epidemics diseases in small populations and in wireless communication networks among many others. In this work we present a novel hybrid algorithm for simulating individual trajectories which adaptively switches between the SSA and the Chernoff tauleap methods. This allows us to: (a) control the global exit probability of any simulated trajectory, (b) obtain accurate and computable estimates for the expected value of any smooth observable of the process with minimal computational work.

  20. Hybrid Chernoff Tau-Leap

    KAUST Repository

    Moraes, Alvaro

    2015-01-07

    Markovian pure jump processes can model many phenomena, e.g. chemical reactions at molecular level, protein transcription and translation, spread of epidemics diseases in small populations and in wireless communication networks among many others. In this work we present a novel hybrid algorithm for simulating individual trajectories which adaptively switches between the SSA and the Chernoff tauleap methods. This allows us to: (a) control the global exit probability of any simulated trajectory, (b) obtain accurate and computable estimates for the expected value of any smooth observable of the process with minimal computational work.

  1. Hybrid Chernoff Tau-Leap

    KAUST Repository

    Moraes, Alvaro

    2016-01-06

    Markovian pure jump processes can model many phenomena, e.g. chemical reactions at molecular level, protein transcription and translation, spread of epidemics diseases in small populations and in wireless communication networks among many others. In this work we present a novel hybrid algorithm for simulating individual trajectories which adaptively switches between the SSA and the Chernoff tauleap methods. This allows us to: (a) control the global exit probability of any simulated trajectory, (b) obtain accurate and computable estimates for the expected value of any smooth observable of the process with minimal computational work.

  2. Nanofabrication of Hybrid Optoelectronic Devices

    Science.gov (United States)

    Dibos, Alan Michael

    The material requirements for optoelectronic devices can vary dramatically depending on the application. Often disparate material systems need to be combined to allow for full device functionality. At the nanometer scale, this can often be challenging because of the inherent chemical and structural incompatibilities of nanofabrication. This dissertation concerns the integration of seemingly dissimilar materials into hybrid optoelectronic devices for photovoltaic, plasmonic, and photonic applications. First, we show that combining a single strip of conjugated polymer and inorganic nanowire can yield a nanoscale solar cell, and modeling of optical absorption and exciton diffusion in this device can provide insight into the efficiency of charge separation. Second, we use an on-chip nanowire light emitting diode to pump a colloidal quantum dot coupled to a silver waveguide. The resulting device is an electro-optic single plasmon source. Finally, we transfer diamond waveguides onto near-field avalanche photodiodes fabricated from GaAs. Embedded in the diamond waveguides are nitrogen vacancy color centers, and the mapping of emission from these single-photon sources is demonstrated using our on-chip detectors, eliminating the need for external photodetectors on an optical table. These studies show the promise of hybrid optoelectronic devices at the nanoscale with applications in alternative energy, optical communication, and quantum optics.

  3. Quantum technologies with hybrid systems.

    Science.gov (United States)

    Kurizki, Gershon; Bertet, Patrice; Kubo, Yuimaru; Mølmer, Klaus; Petrosyan, David; Rabl, Peter; Schmiedmayer, Jörg

    2015-03-31

    An extensively pursued current direction of research in physics aims at the development of practical technologies that exploit the effects of quantum mechanics. As part of this ongoing effort, devices for quantum information processing, secure communication, and high-precision sensing are being implemented with diverse systems, ranging from photons, atoms, and spins to mesoscopic superconducting and nanomechanical structures. Their physical properties make some of these systems better suited than others for specific tasks; thus, photons are well suited for transmitting quantum information, weakly interacting spins can serve as long-lived quantum memories, and superconducting elements can rapidly process information encoded in their quantum states. A central goal of the envisaged quantum technologies is to develop devices that can simultaneously perform several of these tasks, namely, reliably store, process, and transmit quantum information. Hybrid quantum systems composed of different physical components with complementary functionalities may provide precisely such multitasking capabilities. This article reviews some of the driving theoretical ideas and first experimental realizations of hybrid quantum systems and the opportunities and challenges they present and offers a glance at the near- and long-term perspectives of this fascinating and rapidly expanding field.

  4. Quantum technologies with hybrid systems

    Science.gov (United States)

    Kurizki, Gershon; Bertet, Patrice; Kubo, Yuimaru; Mølmer, Klaus; Petrosyan, David; Rabl, Peter; Schmiedmayer, Jörg

    2015-01-01

    An extensively pursued current direction of research in physics aims at the development of practical technologies that exploit the effects of quantum mechanics. As part of this ongoing effort, devices for quantum information processing, secure communication, and high-precision sensing are being implemented with diverse systems, ranging from photons, atoms, and spins to mesoscopic superconducting and nanomechanical structures. Their physical properties make some of these systems better suited than others for specific tasks; thus, photons are well suited for transmitting quantum information, weakly interacting spins can serve as long-lived quantum memories, and superconducting elements can rapidly process information encoded in their quantum states. A central goal of the envisaged quantum technologies is to develop devices that can simultaneously perform several of these tasks, namely, reliably store, process, and transmit quantum information. Hybrid quantum systems composed of different physical components with complementary functionalities may provide precisely such multitasking capabilities. This article reviews some of the driving theoretical ideas and first experimental realizations of hybrid quantum systems and the opportunities and challenges they present and offers a glance at the near- and long-term perspectives of this fascinating and rapidly expanding field. PMID:25737558

  5. Hybrid polypeptides having cellobiohydrolase activity and polynucleotides encoding same

    Science.gov (United States)

    Liu, Ye; Shaghasi, Tarana

    2016-11-01

    The present invention provides hybrid polypeptides having cellobiohydrolase activity. The present invention also provides polynucleotides encoding the hybrid polypeptides; nucleic acid constructs, vectors and host cells comprising the polynucleotides; and processes of using the hybrid polypeptides.

  6. Tunnel and electrostatic coupling in graphene-LaAlO3/SrTiO3 hybrid systems

    Directory of Open Access Journals (Sweden)

    I. Aliaj

    2016-06-01

    Full Text Available We report on the transport properties of hybrid devices obtained by depositing graphene on a LaAlO3/SrTiO3 oxide junction hosting a 4 nm-deep 2-dimensional electron system. At low graphene-oxide inter-layer bias, the two electron systems are electrically isolated, despite their small spatial separation. A very efficient reciprocal gating of the two neighboring 2-dimensional systems is shown. A pronounced rectifying behavior is observed for larger bias values and ascribed to the interplay between electrostatic field-effects and tunneling across the LaAlO3 barrier. The relevance of these results in the context of strongly coupled bilayer systems is discussed.

  7. Control for a class of hybrid systems

    NARCIS (Netherlands)

    J.H. van Schuppen (Jan)

    1997-01-01

    textabstractA hybrid control system is a control theoretic model for a computer controlled engineering system. A definition of a hybrid control system is formulated that consists of a product of a finite state automaton and of a family of continuous control systems. An example of a transportation

  8. Hybrid Therapy Regimen for Helicobacter Pylori Eradication

    Directory of Open Access Journals (Sweden)

    Zhi-Qiang Song

    2016-01-01

    Conclusions: Hybrid therapy showed wide differences in the efficacy but consistently good compliance and safety across different regions. Dual clarithromycin and metronidazole resistance were the key factor to efficacy. Hybrid therapy was similar to sequential or concomitant therapy in the efficacy, safety, and compliance.

  9. Hybrid Compounding in New Zealand English

    Science.gov (United States)

    Degani, Marta; Onysko, Alexander

    2010-01-01

    This study investigates hybrid compound formation of Maori and English terms in present day New Zealand English (NZE). On the background of Maori and English language contact, the phenomenon of hybrid compounding emerges as a process that, on the one hand, symbolizes the vitality of the Maori element in NZE and, on the other hand, marks the…

  10. DSP Control of Line Hybrid Active Filter

    DEFF Research Database (Denmark)

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.;

    2005-01-01

    Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter ...

  11. (Hybrid) Baryons Quantum Numbers and Adiabatic Potentials

    CERN Document Server

    Page, P R

    1999-01-01

    We construct (hybrid) baryons in the flux-tube model of Isgur and Paton. In the limit of adiabatic quark motion, we build proper eigenstates of orbital angular momentum and indicate the flavour, spin, chirality and J^P of (hybrid) baryons. The adiabatic potential is calculated as a function of the quark positions.

  12. Symmetry reduction for stochastic hybrid systems

    NARCIS (Netherlands)

    Bujorianu, L.M.; Katoen, J.P.

    2009-01-01

    This paper is focused on adapting symmetry reduction, a technique that is highly successful in traditional model checking, to stochastic hybrid systems. We first show that performability analysis of stochastic hybrid systems can be reduced to a stochastic reachability analysis (SRA). Then, we genera

  13. Symmetry Reduction For Stochastic Hybrid Systems

    NARCIS (Netherlands)

    Bujorianu, L.M.; Katoen, J.P.

    2008-01-01

    This paper is focused on adapting symmetry reduction, a technique that is highly successful in traditional model checking, to stochastic hybrid systems. To that end, we first show that performability analysis of stochastic hybrid systems can be reduced to a stochastic reachability analysis (SRA). Th

  14. Hybrid Composite of Polyaniline Containing Carbon Nanotube

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Carbon nanotube-polyaniline hybrid material was synthesized by emulsion polymerization in-situ. The morphology of hybrid material was studied by TEM and X-ray diffraction. The conductivity of nanocomposite increases with the increasing of carbon nanotube content because of the new conductivity passageways formed by carbon nanotubes.

  15. Computer code for intraply hybrid composite design

    Science.gov (United States)

    Chamis, C. C.; Sinclair, J. H.

    1981-01-01

    A computer program has been developed and is described herein for intraply hybrid composite design (INHYD). The program includes several composite micromechanics theories, intraply hybrid composite theories and a hygrothermomechanical theory. These theories provide INHYD with considerable flexibility and capability which the user can exercise through several available options. Key features and capabilities of INHYD are illustrated through selected samples.

  16. Next-generation hybridization and introgression

    Science.gov (United States)

    Twyford, A D; Ennos, R A

    2012-01-01

    Hybridization has a major role in evolution—from the introgression of important phenotypic traits between species, to the creation of new species through hybrid speciation. Molecular studies of hybridization aim to understand the class of hybrids and the frequency of introgression, detect the signature of ancient hybridization, and understand the behaviour of introgressed loci in their new genomic background. This often involves a large investment in the design and application of molecular markers, leading to a compromise between the depth and breadth of genomic data. New techniques designed to assay a large sub-section of the genome, in association with next-generation sequencing (NGS) technologies, will allow genome-wide hybridization and introgression studies in organisms with no prior sequence data. These detailed genotypic data will unite the breadth of sampling of loci characteristic of population genetics with the depth of sequence information associated with molecular phylogenetics. In this review, we assess the theoretical and methodological constraints that limit our understanding of natural hybridization, and promote the use of NGS for detecting hybridization and introgression between non-model organisms. We also make recommendations for the ways in which emerging techniques, such as pooled barcoded amplicon sequencing and restriction site-associated DNA tags, should be used to overcome current limitations, and enhance our understanding of this evolutionary significant process. PMID:21897439

  17. Hybrid logics with infinitary proof systems

    NARCIS (Netherlands)

    Kooi, Barteld; Renardel de Lavalette, Gerard; Verbrugge, Rineke

    2006-01-01

    We provide a strongly complete infinitary proof system for hybrid logic. This proof system can be extended with countably many sequents. Thus, although these logics may be non-compact, strong completeness proofs are provided for infinitary hybrid versions of non-compact logics like ancestral logic a

  18. Evaluating the Pedagogical Potential of Hybrid Models

    Science.gov (United States)

    Levin, Tzur; Levin, Ilya

    2013-01-01

    The paper examines how the use of hybrid models--that consist of the interacting continuous and discrete processes--may assist in teaching system thinking. We report an experiment in which undergraduate students were asked to choose between a hybrid and a continuous solution for a number of control problems. A correlation has been found between…

  19. Hybrid reactors: Nuclear breeding or energy production?

    Energy Technology Data Exchange (ETDEWEB)

    Piera, Mireia [UNED, ETSII-Dp Ingenieria Energetica, c/Juan del Rosal 12, 28040 Madrid (Spain); Lafuente, Antonio; Abanades, Alberto; Martinez-Val, J.M. [ETSII-UPM, c/Jose Gutierrez Abascal 2, 28006 Madrid (Spain)

    2010-09-15

    After reviewing the long-standing tradition on hybrid research, an assessment model is presented in order to characterize the hybrid performance under different objectives. In hybrids, neutron multiplication in the subcritical blanket plays a major role, not only for energy production and nuclear breeding, but also for tritium breeding, which is fundamental requirement in fusion-fission hybrids. All three objectives are better achieved with high values of the neutron multiplication factor (k-eff) with the obvious and fundamental limitation that it cannot reach criticality under any event, particularly, in the case of a loss of coolant accident. This limitation will be very important in the selection of the coolant. Some general considerations will be proposed, as guidelines for assessing the hybrid potential in a given scenario. Those guidelines point out that hybrids can be of great interest for the future of nuclear energy in a framework of Sustainable Development, because they can contribute to the efficient exploitation of nuclear fuels, with very high safety features. Additionally, a proposal is presented on a blanket specially suited for fusion-fission hybrids, although this reactor concept is still under review, and new work is needed for identifying the most suitable blanket composition, which can vary depending on the main objective of the hybrid. (author)

  20. Turbo Codes with Hybrid Interleaving Mode

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In the investigation of turbo codes, either random interleavers or structured interleavers are used. Combined two kinds of interleavers in one turbo encoder, a hybrid interleaving mode is proposed in this paper. Computer simulations show that the performance of turbo codes with the hybrid interleaving mode is better than that with the typical interleaving mode.