WorldWideScience

Sample records for individual electronic states

  1. Current state in the research on electronic monitoring systems for the security and flow of objects and individuals

    Directory of Open Access Journals (Sweden)

    Man Dietrich Marcela

    2017-01-01

    Full Text Available This paper sets forth the current state of security systems in prisons from Romania and around the world, particularly aiming electronic systems of monitoring the flow of people, materials control and perimeter security, focusing on the research results concluded by motion detection tests and devices. The currently used systems were observed in order to put an analysis of the methodology together and implement and perfect these systems in protected areas. The protection of citizens must be performed to the extent that is allowed by the legislation.

  2. Two electron Rydberg states

    International Nuclear Information System (INIS)

    Cooke, W.E.

    1981-01-01

    This paper addresses the study of two-electron Rydberg atoms. With Multichannel Quantum Defect Theory (MQDT), there is a technique for characterizing a spectra in terms of a small number of parameters. A survey of some important effects specific to two-electon Rydberg states, using primarily the alkaline earth atoms for examples, is made. The remainder of the paper deals with a discussion of the electron-electron interaction, including some of the basic points of MQDT. Energy exchange between two electrons is also addressed

  3. Electronic-cigarette use by individuals in treatment for substance abuse: A survey of 24 treatment centers in the United States.

    Science.gov (United States)

    Gubner, Noah R; Andrews, K Blakely; Mohammad-Zadeh, Ana; Lisha, Nadra E; Guydish, Joseph

    2016-12-01

    Prevalence and reasons for using electronic cigarettes (e-cigarettes) was examined among patients enrolled in 24 substance abuse treatment centers in the United States (N=1113). Prevalence of e-cigarette use was assessed for the full sample. Bivariate analyses and multivariate logistic regression were used to identify characteristics associated with e-cigarette use among current cigarette smokers (the majority of e-cigarette users). Overall 55.5% of the sample reported lifetime use of e-cigarettes, and 30.5% reported using e-cigarettes in the past 30days (current users). The main reasons for using e-cigarettes were (a) at times/places when smoking was prohibited (53.5%), and (b) as a way to quit/reduce cigarette smoking (50.3%). Daily vs non-daily e-cigarette users were more likely to use e-cigarettes both as a way to reduce health risks, and as a way to quit/reduce cigarette smoking. A majority of e-cigarette users (87.1%) reported dual use of e-cigarettes and tobacco cigarettes during the past month. Among current cigarette smokers, those that also used e-cigarettes smoked more cigarettes per day, were more likely to have made a past year cigarette quit attempt, and to have tried nicotine replacement therapy compared to cigarette only smokers. There was a high rate of dual e-cigarette and cigarette use by persons enrolled in addiction treatment. E-cigarette users may be heavier cigarette smokers trying to quit or reduce their cigarette smoking. However, e-cigarettes were also used at times when individuals could not smoke cigarettes. Substance abuse treatment centers developing tobacco policies need to consider these potentially conflicting reasons for using e-cigarettes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Electronic-cigarette use by individuals in treatment for substance abuse: A survey of 24 treatment centers in the United States

    OpenAIRE

    Gubner, Noah R.; Andrews, K. Blakely; Mohammad-Zadeh, Ana; Lisha, Nadra E.; Guydish, Joseph

    2016-01-01

    Prevalence and reasons for using electronic cigarettes (e-cigarettes) was examined among patients enrolled in 24 substance abuse treatment centers in the United States (N=1,113). Prevalence of e-cigarette use was assessed for the full sample. Bivariate analyses and multivariate logistic regression were used to identify characteristics associated with e-cigarette use among current cigarette smokers (the majority of e-cigarette users). Overall 55.5% of the sample reported lifetime use of e-ciga...

  5. Electronic states of myricetin

    DEFF Research Database (Denmark)

    Vojta, Danijela; Karlsen, Eva; Spanget-Larsen, Jens

    2017-01-01

    Myricetin (3,3',4',5,5',7'-hexahydroxyflavone) was investigated by linear dichroism spectroscopy on molecular samples partially aligned in stretched poly(vinyl alcohol) (PVA). At least five electronic transitions in the range 40000 – 20000 cm–1 were characterized with respect to their wavenumbers......, relative intensities, and transition moment directions. The observed bands were assigned to electronic transitions predicted with TD-B3LYP/6-31+G(d,p)....

  6. Introduction to solid state electronics

    CERN Document Server

    Wang, FFY

    1989-01-01

    This textbook is specifically tailored for undergraduate engineering courses offered in the junior year, providing a thorough understanding of solid state electronics without relying on the prerequisites of quantum mechanics. In contrast to most solid state electronics texts currently available, with their generalized treatments of the same topics, this is the first text to focus exclusively and in meaningful detail on introductory material. The original text has already been in use for 10 years. In this new edition, additional problems have been added at the end of most chapters. These proble

  7. THE INDIVIDUAL RIGHTS AND THE STATE

    Directory of Open Access Journals (Sweden)

    DANA TITA

    2011-04-01

    Full Text Available The concept of man’s individual rights appeared a long time ago as a means of the individual’s protection in relationship with the others. Living in a society, man interacts with other people, and these relations are regulated by certain rules. Once the state was formed, these rules become increasingly powerful while the concept of freedom is differently acknowledged.What actually lay at the basis of individual rights’ development was the concept of natural right which appeared in ancient Greece, and which can be traced throughout history like Ariadne’s thread, guiding different thoughtschools. Human’s fundamental rights are sanctioned only after being put down in the constitutions of different states, and once regional and international protection instruments are created. Nevertheless, in countries controlled by totalitarian regimes, human rights were infringed, the individual having to obey the collective community.These regimes having collapsed, individual rights underwent a change for the better, but they also came to a standstill due to 9/11 or Ground Zero. After this event, and in the context of the fight against terrorism, individual freedom was limited in the name of freedom itself, and individual rights are currently regressing as to the possibility of being exercised.

  8. State-selective electron capture

    International Nuclear Information System (INIS)

    Dunford, R.W.; Liu, C.J.; Berry, H.G.; Pardo, R.C.; Raphaelian, M.L.A.

    1988-01-01

    We report results from a new atomic physics program using the Argonne PII ECR ion source which is being built as part of the upgrade of the Argonne Tandem-Linear Accelerator (ATLAS). Our initial experiments have been aimed at studying state-selective electron capture in ion-atom collisions using the technique of Photon Emission Spectroscopy. We are extending existing cross section measurements at low energy ( 6+ and O 7+ on He and H 2 targets in the energy range from 1-105 keV/amu. We also present uv spectra obtained in collisions of O 6+ , O 5+ and N 5+ on a sodium target. 4 refs., 2 figs., 1 tab

  9. Resting State Network Estimation in Individual Subjects

    Science.gov (United States)

    Hacker, Carl D.; Laumann, Timothy O.; Szrama, Nicholas P.; Baldassarre, Antonello; Snyder, Abraham Z.

    2014-01-01

    Resting-state functional magnetic resonance imaging (fMRI) has been used to study brain networks associated with both normal and pathological cognitive function. The objective of this work is to reliably compute resting state network (RSN) topography in single participants. We trained a supervised classifier (multi-layer perceptron; MLP) to associate blood oxygen level dependent (BOLD) correlation maps corresponding to pre-defined seeds with specific RSN identities. Hard classification of maps obtained from a priori seeds was highly reliable across new participants. Interestingly, continuous estimates of RSN membership retained substantial residual error. This result is consistent with the view that RSNs are hierarchically organized, and therefore not fully separable into spatially independent components. After training on a priori seed-based maps, we propagated voxel-wise correlation maps through the MLP to produce estimates of RSN membership throughout the brain. The MLP generated RSN topography estimates in individuals consistent with previous studies, even in brain regions not represented in the training data. This method could be used in future studies to relate RSN topography to other measures of functional brain organization (e.g., task-evoked responses, stimulation mapping, and deficits associated with lesions) in individuals. The multi-layer perceptron was directly compared to two alternative voxel classification procedures, specifically, dual regression and linear discriminant analysis; the perceptron generated more spatially specific RSN maps than either alternative. PMID:23735260

  10. Electron emission from individual indium arsenide semiconductor nanowires

    NARCIS (Netherlands)

    Heeres, E.C.; Bakkers, E.P.A.M.; Roest, A.L.; Kaiser, M.A.; Oosterkamp, T.H.; Jonge, de N.

    2007-01-01

    A procedure was developed to mount individual semiconductor indium arsenide nanowires onto tungsten support tips to serve as electron field-emission sources. The electron emission properties of the single nanowires were precisely determined by measuring the emission pattern, current-voltage curve,

  11. States of the electron in hydrocarbon liquids

    International Nuclear Information System (INIS)

    Mozumder, A.

    2005-01-01

    Some features of the stationary and dynamic states of the electron are critically examined. Outline of a quantum mechanical description of electron thermalization is attempted qualitatively. The effects of both the mean free path and the reaction inefficiency on electron-ion geminate escape probability are investigated by a recently developed Metropolis method. The trapped state is interpreted in terms of Anderson localization, yielding an approximate number of molecules interacting with the trapped electron

  12. Multiple electron generation in a sea of electronic states

    Science.gov (United States)

    Witzel, Wayne; Shabaev, Andrew; Efros, Alexander; Hellberg, Carl; Verne, Jacobs

    2009-03-01

    In traditional bulk semiconductor photovoltaics (PVs), each photon may excite a single electron-hole, wasting excess energy beyond the band-gap as heat. In nanocrystals, multiple excitons can be generated from a single photon, enhancing the PV current. Multiple electron generation (MEG) may result from Coulombic interactions of the confined electrons. Previous investigations have been based on incomplete or over-simplified electronic-state representations. We present results of quantum simulations that include hundreds of thousands of configuration states and show how the complex dynamics, even in a closed electronic system, yields a saturated MEG effect on a femtosecond timescale. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  13. Solid-state physics for electronics

    CERN Document Server

    Moliton, Andre

    2009-01-01

    Describing the fundamental physical properties of materials used in electronics, the thorough coverage of this book will facilitate an understanding of the technological processes used in the fabrication of electronic and photonic devices. The book opens with an introduction to the basic applied physics of simple electronic states and energy levels. Silicon and copper, the building blocks for many electronic devices, are used as examples. Next, more advanced theories are developed to better account for the electronic and optical behavior of ordered materials, such as diamond, and disordered ma

  14. Electron transfer from electronic excited states to sub-vacuum electron traps in amorphous ice

    International Nuclear Information System (INIS)

    Vichnevetski, E.; Bass, A.D.; Sanche, L.

    2000-01-01

    We investigate the electron stimulated yield of electronically excited argon atoms (Ar * ) from monolayer quantities of Ar deposited onto thin films of amorphous ice. Two peaks of narrow width ( - electron-exciton complex into exciton states, by the transfer of an electron into a sub-vacuum electron state within the ice film. However, the 10.7 eV feature is shifted to lower energy since electron attachment to Ar occurs within small pores of amorphous ice. In this case, the excess electron is transferred into an electron trap below the conduction band of the ice layer

  15. Electron spectroscopy of nanodiamond surface states

    Energy Technology Data Exchange (ETDEWEB)

    Belobrov, P.I.; Bursill, L.A.; Maslakov, K.I.; Dementjev, A.P

    2003-06-15

    Electronic states of nanodiamond (ND) were investigated by PEELS, XPS and CKVV Auger spectra. Parallel electron energy loss spectra (PEELS) show that the electrons inside of ND particles are sp{sup 3} hybridized but there is a surface layer containing distinct hybridized states. The CKVV Auger spectra imply that the HOMO of the ND surface has a shift of 2.5 eV from natural diamond levels of {sigma}{sub p} up to the Fermi level. Hydrogen (H) treatment of natural diamond surface produces a chemical state indistinguishable from that of ND surfaces using CKVV. The ND electronic structure forms {sigma}{sub s}{sup 1}{sigma}{sub p}{sup 2}{pi}{sup 1} surface states without overlapping of {pi}-levels. Surface electronic states, including surface plasmons, as well as phonon-related electronic states of the ND surface are also interesting and may also be important for field emission mechanisms from the nanostructured diamond surface.

  16. Hospital nurses' individual priorities, internal psychological states and work motivation.

    Science.gov (United States)

    Toode, K; Routasalo, P; Helminen, M; Suominen, T

    2014-09-01

    This study looks to describe the relationships between hospital nurses' individual priorities, internal psychological states and their work motivation. Connections between hospital nurses' work-related needs, values and work motivation are essential for providing safe and high quality health care. However, there is insufficient empirical knowledge concerning these connections for the practice development. A cross-sectional empirical research study was undertaken. A total of 201 registered nurses from all types of Estonian hospitals filled out an electronic self-reported questionnaire. Descriptive statistics, Mann-Whitney, Kruskal-Wallis and Spearman's correlation were used for data analysis. In individual priorities, higher order needs strength were negatively correlated with age and duration of service. Regarding nurses' internal psychological states, central hospital nurses had less sense of meaningfulness of work. Nurses' individual priorities (i.e. their higher order needs strength and shared values with the organization) correlated with their work motivation. Their internal psychological states (i.e. their experienced meaningfulness of work, experienced responsibility for work outcomes and their knowledge of results) correlated with intrinsic work motivation. Nurses who prioritize their higher order needs are more motivated to work. The more their own values are compatible with those of the organization, the more intrinsically motivated they are likely to be. Nurses' individual achievements, autonomy and training are key factors which influence their motivation to work. The small sample size and low response rate of the study limit the direct transferability of the findings to the wider nurse population, so further research is needed. This study highlights the need and importance to support nurses' professional development and self-determination, in order to develop and retain motivated nurses. It also indicates a need to value both nurses and nursing in

  17. Solid-state electronic devices an introduction

    CERN Document Server

    Papadopoulos, Christo

    2014-01-01

    A modern and concise treatment of the solid state electronic devices that are fundamental to electronic systems and information technology is provided in this book. The main devices that comprise semiconductor integrated circuits are covered in a clear manner accessible to the wide range of scientific and engineering disciplines that are impacted by this technology. Catering to a wider audience is becoming increasingly important as the field of electronic materials and devices becomes more interdisciplinary, with applications in biology, chemistry and electro-mechanical devices (to name a few) becoming more prevalent. Updated and state-of-the-art advancements are included along with emerging trends in electronic devices and their applications. In addition, an appendix containing the relevant physical background will be included to assist readers from different disciplines and provide a review for those more familiar with the area. Readers of this book can expect to derive a solid foundation for understanding ...

  18. Kinetic and electron-electron energies for convex sums of ground state densities with degeneracies and fractional electron number

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Mel, E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States); Department of Physics, North Carolina A and T State University, Greensboro, North Carolina 27411 (United States); Department of Chemistry, Tulane University, New Orleans, Louisiana 70118 (United States); Anderson, James S. M.; Zadeh, Farnaz Heidar; Ayers, Paul W., E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario (Canada)

    2014-05-14

    Properties of exact density functionals provide useful constraints for the development of new approximate functionals. This paper focuses on convex sums of ground-level densities. It is observed that the electronic kinetic energy of a convex sum of degenerate ground-level densities is equal to the convex sum of the kinetic energies of the individual degenerate densities. (The same type of relationship holds also for the electron-electron repulsion energy.) This extends a known property of the Levy-Valone Ensemble Constrained-Search and the Lieb Legendre-Transform refomulations of the Hohenberg-Kohn functional to the individual components of the functional. Moreover, we observe that the kinetic and electron-repulsion results also apply to densities with fractional electron number (even if there are no degeneracies), and we close with an analogous point-wise property involving the external potential. Examples where different degenerate states have different kinetic energy and electron-nuclear attraction energy are given; consequently, individual components of the ground state electronic energy can change abruptly when the molecular geometry changes. These discontinuities are predicted to be ubiquitous at conical intersections, complicating the development of universally applicable density-functional approximations.

  19. State Membership: A Question of Individual Choice

    OpenAIRE

    Duarte, Melina

    2016-01-01

    The papers I, III and IV of this thesis are not available in Munin. Paper I: I. Duarte, M.: "Right to Hospitality, Right to Membership: a Critical Review of Kant's and Benhabib's Cosmopolitan Accounts on Immigration and Borders.". Published version available in "Varieties of Liberalism: Contemporary Challenges. Alnes, J. H. and Manuel Toscano (eds.), ISBN: 978-1443858120. Newcastle: Cambridge Scholars Publishing, p.:204-222. Paper III:Duarte, M.: "State Membership: Contesting Natur...

  20. Electronic States in Thorium under Pressure

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Jan, J. P.

    1980-01-01

    We have used the local-density formalism and the atomic-sphere approximation to calculate self-consistently the electronic properties of thorium at pressures up to 400 kbar. The derived equation of state agrees very well with static pressure experiments and shock data. Below the Fermi level (EF......) the electronic band structure is formed by 7s and 6d states while the bottom of a relatively broad 5f band is positioned 0.07 Ry above EF. The calculated extremal areas of the Fermi surface and their calculated pressure dependence agree with earlier calculations and with de Haas-van Alphen measurements...

  1. Excitation of lowest electronic states of thymine by slow electrons

    Science.gov (United States)

    Chernyshova, I. V.; Kontros, E. J.; Markush, P. P.; Shpenik, O. B.

    2013-11-01

    Excitation of lowest electronic states of the thymine molecules in the gas phase is studied by elec- tron energy loss spectroscopy. In addition to dipole-allowed transitions to singlet states, transitions to the lowest triplet states were observed. The low-energy features of the spectrum at 3.66 and 4.61 eV are identified with the excitation of the first triplet states 13 A' (π → π*) and 13 A″ ( n → π*). The higher-lying features at 4.96, 5.75, 6.17, and 7.35 eV are assigned mainly to the excitation of the π → π* transitions to the singlet states of the molecule. The excitation dynamics of the lowest states is studied. It is found that the first triplet state 13 A'(π → π*) is most efficiently excited at a residual energy close to zero, while the singlet 21 A'(π → π*) state is excited with almost identical efficiency at different residual energies.

  2. Electron affinity and excited states of methylglyoxal

    Science.gov (United States)

    Dauletyarov, Yerbolat; Dixon, Andrew R.; Wallace, Adam A.; Sanov, Andrei

    2017-07-01

    Using photoelectron imaging spectroscopy, we characterized the anion of methylglyoxal (X2A″ electronic state) and three lowest electronic states of the neutral methylglyoxal molecule: the closed-shell singlet ground state (X1A'), the lowest triplet state (a3A″), and the open-shell singlet state (A1A″). The adiabatic electron affinity (EA) of the ground state, EA(X1A') = 0.87(1) eV, spectroscopically determined for the first time, compares to 1.10(2) eV for unsubstituted glyoxal. The EAs (adiabatic attachment energies) of two excited states of methylglyoxal were also determined: EA(a3A″) = 3.27(2) eV and EA(A1A″) = 3.614(9) eV. The photodetachment of the anion to each of these two states produces the neutral species near the respective structural equilibria; hence, the a3A″ ← X2A″ and A1A″ ← X2A″ photodetachment transitions are dominated by intense peaks at their respective origins. The lowest-energy photodetachment transition, on the other hand, involves significant geometry relaxation in the X1A' state, which corresponds to a 60° internal rotation of the methyl group, compared to the anion structure. Accordingly, the X1A' ← X2A″ transition is characterized as a broad, congested band, whose vertical detachment energy, VDE = 1.20(4) eV, significantly exceeds the adiabatic EA. The experimental results are in excellent agreement with the ab initio predictions using several equation-of-motion methodologies, combined with coupled-cluster theory.

  3. Excited state electron affinity calculations for aluminum

    Science.gov (United States)

    Hussein, Adnan Yousif

    2017-08-01

    Excited states of negative aluminum ion are reviewed, and calculations of electron affinities of the states (3s^23p^2)^1D and (3s3p^3){^5}{S}° relative to the (3s^23p)^2P° and (3s3p^2)^4P respectively of the neutral aluminum atom are reported in the framework of nonrelativistic configuration interaction (CI) method. A priori selected CI (SCI) with truncation energy error (Bunge in J Chem Phys 125:014107, 2006) and CI by parts (Bunge and Carbó-Dorca in J Chem Phys 125:014108, 2006) are used to approximate the valence nonrelativistic energy. Systematic studies of convergence of electron affinity with respect to the CI excitation level are reported. The calculated value of the electron affinity for ^1D state is 78.675(3) meV. Detailed Calculations on the ^5S°c state reveals that is 1216.8166(3) meV below the ^4P state.

  4. Official dosimetry with individual electronic dosemeters - the concept in Germany

    International Nuclear Information System (INIS)

    Czarwinski, R.; Kaulard, J.; Pfeffer, W.

    2005-01-01

    Full text: Presently, in Germany passive dosemeters (film batches, RPL, TLD) are used for the official individual monitoring of occupational exposed personal. The application of electronic individual dosemeters (EPD) is carried out mainly for the operative radiation protection control particularly in nuclear power engineering companies, big hospitals und research centres. This means in such institutions double monitoring exists - legally and operatively. A crucial advantage of EPD compared to passive dosemeter is the possibility to adapt the monitoring period to the working time in the control area, e.g. a job related monitoring is available. Germany started a project for an optimized implementation of EPD into the official dosimetry. Objective of the project whose results will be described in the paper is the harmonization of radiation protection of companies workers and outside workers concerning the record of individual and job related exposures. The approval of the EPD by the Federal and Laender authorities as an official dosimetric system demands the implementation of special requirements concerning the data acquisition, data transfer and data evaluation. These issues are focuses of the Federal research project, supervised by the Federal Office for Radiation Protection (BfS) and performed by the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS), Cologne to develop a concept in the first stage. (author)

  5. Correlated electron motion, flux states and superconductivity

    International Nuclear Information System (INIS)

    Lederer, P.; Poilblanc, D.; Rice, T.K.

    1989-01-01

    This paper discusses how, when the on-site correlation is strong, electrons can move by usual hopping only on to empty sites but they can exchange position with their neighbors by a correlated motion. The phase in the former process is fixed and it favors Bloch states. When the concentration of empty sites is small then the latter process dominates and one is free to introduce a phase provided it is chosen to be the same for ↑ and ↓-spin electrons. Since for a partly filled band of non-interacting electrons the introduction of a uniform commensurate flux lowers the energy, the correlated motion can lead to a physical mechanism to generate flux states. These states have a collective gauge variable which is the same for ↑ and ↓-spins and superconducting properties are obtained by expanding around the optimum gauge determined by the usual kinetic energy term. If this latter term has singularities at special fillings then these may affect the superconducting properties

  6. Probing Individual Ice Nucleation Events with Environmental Scanning Electron Microscopy

    Science.gov (United States)

    Wang, Bingbing; China, Swarup; Knopf, Daniel; Gilles, Mary; Laskin, Alexander

    2016-04-01

    Heterogeneous ice nucleation is one of the processes of critical relevance to a range of topics in the fundamental and the applied science and technologies. Heterogeneous ice nucleation initiated by particles proceeds where microscopic properties of particle surfaces essentially control nucleation mechanisms. Ice nucleation in the atmosphere on particles governs the formation of ice and mixed phase clouds, which in turn influence the Earth's radiative budget and climate. Heterogeneous ice nucleation is still insufficiently understood and poses significant challenges in predictive understanding of climate change. We present a novel microscopy platform allowing observation of individual ice nucleation events at temperature range of 193-273 K and relative humidity relevant for ice formation in the atmospheric clouds. The approach utilizes a home built novel ice nucleation cell interfaced with Environmental Scanning Electron Microscope (IN-ESEM system). The IN-ESEM system is applied for direct observation of individual ice formation events, determining ice nucleation mechanisms, freezing temperatures, and relative humidity onsets. Reported microanalysis of the ice nucleating particles (INP) include elemental composition detected by the energy dispersed analysis of X-rays (EDX), and advanced speciation of the organic content in particles using scanning transmission x-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). The performance of the IN-ESEM system is validated through a set of experiments with kaolinite particles with known ice nucleation propensity. We demonstrate an application of the IN-ESEM system to identify and characterize individual INP within a complex mixture of ambient particles.

  7. Electronic states in a quantum lens

    International Nuclear Information System (INIS)

    Rodriguez, Arezky H.; Trallero-Giner, C.; Ulloa, S. E.; Marin-Antuna, J.

    2001-01-01

    We present a model to find analytically the electronic states in self-assembled quantum dots with a truncated spherical cap (''lens'') geometry. A conformal analytical image is designed to map the quantum dot boundary into a dot with semispherical shape. The Hamiltonian for a carrier confined in the quantum lens is correspondingly mapped into an equivalent operator and its eigenvalues and eigenfunctions for the corresponding Dirichlet problem are analyzed. A modified Rayleigh-Schro''dinger perturbation theory is presented to obtain analytical expressions for the energy levels and wave functions as a function of the spherical cap height b and radius a of the circular cross section. Calculations for a hard wall confinement potential are presented, and the effect of decreasing symmetry on the energy values and eigenfunctions of the lens-shape quantum dot is studied. As the degeneracies of a semicircular geometry are broken for b≠a, our perturbation approach allows tracking of the split states. Energy states and electronic wave functions with m=0 present the most pronounced influence on the reduction of the lens height. The method and expressions presented here can be straightforwardly extended to deal with more general Hamiltonians, including strains and valence-band coupling effects in Group III--V and Group II--VI self-assembled quantum dots

  8. Electronic processes in organic electronics bridging nanostructure, electronic states and device properties

    CERN Document Server

    Kudo, Kazuhiro; Nakayama, Takashi; Ueno, Nobuo

    2015-01-01

    The book covers a variety of studies of organic semiconductors, from fundamental electronic states to device applications, including theoretical studies. Furthermore, innovative experimental techniques, e.g., ultrahigh sensitivity photoelectron spectroscopy, photoelectron yield spectroscopy, spin-resolved scanning tunneling microscopy (STM), and a material processing method with optical-vortex and polarization-vortex lasers, are introduced. As this book is intended to serve as a textbook for a graduate level course or as reference material for researchers in organic electronics and nanoscience from electronic states, fundamental science that is necessary to understand the research is described. It does not duplicate the books already written on organic electronics, but focuses mainly on electronic properties that arise from the nature of organic semiconductors (molecular solids). The new experimental methods introduced in this book are applicable to various materials (e.g., metals, inorganic and organic mater...

  9. Switching behaviour of individual Ag-TCNQ nanowires: an in situ transmission electron microscopy study

    Science.gov (United States)

    Ran, Ke; Rösner, Benedikt; Butz, Benjamin; Fink, Rainer H.; Spiecker, Erdmann

    2016-10-01

    The organic semiconductor silver-tetracyanoquinodimethane (Ag-TCNQ) exhibits electrical switching and memory characteristics. Employing a scanning tunnelling microscopy setup inside a transmission electron microscope, the switching behaviour of individual Ag-TCNQ nanowires (NWs) is investigated in detail. For a large number of NWs, the switching between a high (OFF) and a low (ON) resistance state was successfully stimulated by negative bias sweeps. Fitting the experimental I-V curves with a Schottky emission function makes the switching features prominent and thus enables a direct evaluation of the switching process. A memory cycle including writing, reading and erasing features is demonstrated at an individual NW. Moreover, electronic failure mechanisms due to Joule heating are discussed. These findings have a significant impact on our understanding of the switching behaviour of Ag-TCNQ.

  10. Nanosecond-timescale spin transfer using individual electrons in a quadruple-quantum-dot device

    Energy Technology Data Exchange (ETDEWEB)

    Baart, T. A.; Jovanovic, N.; Vandersypen, L. M. K. [QuTech and Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft (Netherlands); Reichl, C.; Wegscheider, W. [Solid State Physics Laboratory, ETH Zürich, 8093 Zürich (Switzerland)

    2016-07-25

    The ability to coherently transport electron-spin states between different sites of gate-defined semiconductor quantum dots is an essential ingredient for a quantum-dot-based quantum computer. Previous shuttles using electrostatic gating were too slow to move an electron within the spin dephasing time across an array. Here, we report a nanosecond-timescale spin transfer of individual electrons across a quadruple-quantum-dot device. Utilizing enhanced relaxation rates at a so-called hot spot, we can upper bound the shuttle time to at most 150 ns. While actual shuttle times are likely shorter, 150 ns is already fast enough to preserve spin coherence in, e.g., silicon based quantum dots. This work therefore realizes an important prerequisite for coherent spin transfer in quantum dot arrays.

  11. Electron correlations in solid state physics

    International Nuclear Information System (INIS)

    Freericks, J.K.

    1991-04-01

    Exactly solvable models of electron correlations in solid state physics are presented. These models include the spinless Falicov- Kimball model, the t-t'-J model, and the Hubbard model. The spinless Falicov-Kimball model is analyzed in one-dimension. Perturbation theory and numerical techniques are employed to determine the phase diagram at zero temperature. A fractal structure is found where the ground-state changes (discontinuously) at each rational electron filling. The t-t'-J model (strongly interacting limit of a Hubbard model) is studied on eight-site small clusters in the simple-cubic, body-centered-cubic, face-centered-cubic, and square lattices. Symmetry is used to simplify the problem and determine the exact many-body wavefunctions. Ground states are found that exhibit magnetic order or heavy-fermionic character. Attempts to extrapolate to the thermodynamic limit are also made. The Hubbard model is examined on an eight-site square-lattice cluster in the presence of and in the absence of a ''magnetic field'' that couples only to orbital motion. A new magnetic phase is discovered for the ordinary Hubbard model at half-filling. In the ''magnetic field'' case, it is found that the strongly frustrated Heisenberg model may be studied from adiabatic continuation of a tight-binding model (from weak to strong coupling) at one point. The full symmetries of the Hamiltonian are utilized to make the exact diagonalization feasibile. Finally, the presence of ''hidden'' extra symmetry for finite size clusters with periodic boundary conditions is analyzed for a variety of clusters. Moderately sized systems allow nonrigid transformations that map a lattice onto itself preserving its neighbor structure; similar operations are not present in smaller or larger systems. The additional symmetry requires particular representations of the space group to stick together explaining many puzzling degeneracies found in exact diagonalization studies

  12. Electronically shielded solid state charged particle detector

    International Nuclear Information System (INIS)

    Balmer, D.K.; Haverty, T.W.; Nordin, C.W.; Tyree, W.H.

    1996-01-01

    An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite. 1 fig

  13. Characterization of electron states in dense plasmas and its use in atomic kinetics modeling

    International Nuclear Information System (INIS)

    Fisher, D.V.; Maron, Y.

    2003-01-01

    We describe a self-consistent statistical approach to account for plasma density effects in collisional-radiative kinetics. The approach is based on the characterization of three distinct types of electron states, namely, bound, collectivized, and free, and on the formalism of the effective statistical weights (ESW) of the bound states. The present approach accounts for individual and collective effects of the surrounding electrons and ions on atomic (ionic) electron states. High-accuracy expressions for the ESWs of bound states have been derived. The notions of ionization stage population, free electron density, and rate coefficient are redefined in accordance with the present characterization scheme. The modified expressions for the probabilities of electron-impact induced transitions as well as spontaneous and induced radiative transitions are then obtained. The influence of collectivized states on a dense plasma ionization composition is demonstrated to be strong. Examples of calculated ESWs and populations of ionic quantum states for steady state and transient plasmas are given

  14. Differences Between Individual and Societal Health State Valuations

    Science.gov (United States)

    Chapman, Benjamin P.; Franks, Peter; Duberstein, Paul R.; Jerant, Anthony

    2009-01-01

    Objective The concept of “adaptation” has been proposed to account for differences between individual and societal valuations of specific health states in patients with chronic diseases. Little is known about psychological indices of adaptational capacity, which may predict differences in individual and societal valuations of health states. We investigated whether such differences were partially explained by personality traits in chronic disease patients. Research Design Analysis of baseline data of randomized controlled trial. Subjects Three hundred seventy patients with chronic disease. Measures The NEO-five factor inventory measure of personality, EuroQoL-5D (EQ-5D) societal-based, and the EQ visual analogue scale individually-based measures of health valuation. Results Regression analyses modeled Dev, a measure of difference between the EQ-Visual Analogue Scale and EQ-5D, as a function of personality traits, sociodemographic factors, and chronic diseases. Individual valuations were significantly and clinically higher than societal valuations among patients in the second and third quartile of conscientiousness (Dev = 0.08, P = 0.01); among covariates, only depression (Dev = -0.04, P = 0.046) was also associated with Dev. Conclusion Compared with societal valuations of a given health state, persons at higher quartiles of conscientiousness report less disutility associated with poor health. The effect is roughly twice that of some estimates of minimally important clinical differences on the EQ-5D and of depression. Although useful at the aggregate level, societal preference measures may systematically undervalue the health states of more conscientious individuals. Future work should examine the impact this has on individual patient outcome evaluation in clinical studies. PMID:19543121

  15. Mesoscopic Electronics in Solid State Nanostructures

    CERN Document Server

    Heinzel, Thomas

    2007-01-01

    This text treats electronic transport in the regime where conventional textbook models are no longer applicable, including the effect of electronic phase coherence, energy quantization and single-electron charging. This second edition is completely updated and expanded, and now comprises new chapters on spin electronics and quantum information processing, transport in inhomogeneous magnetic fields, organic/molecular electronics, and applications of field effect transistors. The book also provides an overview of semiconductor processing technologies and experimental techniques. With a number of

  16. Maximizing the Use of Electronic Individualized Education Program Software

    Science.gov (United States)

    More, Cori M.; Hart, Juliet E.

    2013-01-01

    With the growing use of technology in today's schools, electronic IEP programs are being adopted by many school districts around the nation as part of special education service delivery. These programs provide a useful technology that can facilitate compliance with IDEA requirements in IEP development while concurrently lessening teacher paperwork…

  17. Long-distance electron transport in individual, living cable bacteria

    DEFF Research Database (Denmark)

    Bjerg, Jesper T; Boschker, Henricus T S; Larsen, Steffen

    2018-01-01

    redox potential was detected, which immediately broke down upon removal of oxygen or laser cutting of the filaments. Without access to oxygen, a rapid shift toward more reduced cytochromes was observed, as electrons were no longer drained from the filament but accumulated in the cellular cytochromes...

  18. The effects of electron-hole separation on the photoconductivity of individual metal oxide nanowires

    International Nuclear Information System (INIS)

    Prades, J D; Hernandez-Ramirez, F; Jimenez-Diaz, R; Manzanares, M; Andreu, T; Cirera, A; Romano-Rodriguez, A; Morante, J R

    2008-01-01

    The responses of individual ZnO nanowires to UV light demonstrate that the persistent photoconductivity (PPC) state is directly related to the electron-hole separation near the surface. Our results demonstrate that the electrical transport in these nanomaterials is influenced by the surface in two different ways. On the one hand, the effective mobility and the density of free carriers are determined by recombination mechanisms assisted by the oxidizing molecules in air. This phenomenon can also be blocked by surface passivation. On the other hand, the surface built-in potential separates the photogenerated electron-hole pairs and accumulates holes at the surface. After illumination, the charge separation makes the electron-hole recombination difficult and originates PPC. This effect is quickly reverted after increasing either the probing current (self-heating by Joule dissipation) or the oxygen content in air (favouring the surface recombination mechanisms). The model for PPC in individual nanowires presented here illustrates the intrinsic potential of metal oxide nanowires to develop optoelectronic devices or optochemical sensors with better and new performances.

  19. Electron holography at atomic dimensions -- Present state

    International Nuclear Information System (INIS)

    Lehmann, M.; Lichte, H.

    1999-01-01

    An electron microscope is a wave optical instrument where the object information is carried by an electron wave. However, an important information, the phase of the electron wave, is lost, because only intensities can be recorded in a conventional electron micrograph. Off-axis electron holography solves this phase problem by encoding amplitude and phase information in an interference pattern, the so-called hologram. After reconstruction, a rather unrestricted wave optical analysis can be performed on a computer. The possibilities as well as the current limitations of off-axis electron holography at atomic dimensions are discussed, and they are illustrated at two applications of structure characterization of ε-NbN and YBCO-1237. Finally, an electron microscope equipped with a Cs-corrector, a monochromator, and a Moellenstedt biprism is outlined for subangstrom holography

  20. Coherent states of an electron in a quantized electromagnetic wave

    International Nuclear Information System (INIS)

    Bagrov, V.G.; Bukhbinder, I.L.; Gitman, D.M.; Lavrov, P.M.

    1977-01-01

    Coherent states for interacting electrons and photons in a plane elecmagnetic wave are found. Trajectories of the electron and the characteristics of the electromagnetic field are investigated. Limiting transition to the given external field is studied

  1. Spin-lattice relaxation of individual solid-state spins

    Science.gov (United States)

    Norambuena, A.; Muñoz, E.; Dinani, H. T.; Jarmola, A.; Maletinsky, P.; Budker, D.; Maze, J. R.

    2018-03-01

    Understanding the effect of vibrations on the relaxation process of individual spins is crucial for implementing nanosystems for quantum information and quantum metrology applications. In this work, we present a theoretical microscopic model to describe the spin-lattice relaxation of individual electronic spins associated to negatively charged nitrogen-vacancy centers in diamond, although our results can be extended to other spin-boson systems. Starting from a general spin-lattice interaction Hamiltonian, we provide a detailed description and solution of the quantum master equation of an electronic spin-one system coupled to a phononic bath in thermal equilibrium. Special attention is given to the dynamics of one-phonon processes below 1 K where our results agree with recent experimental findings and analytically describe the temperature and magnetic-field scaling. At higher temperatures, linear and second-order terms in the interaction Hamiltonian are considered and the temperature scaling is discussed for acoustic and quasilocalized phonons when appropriate. Our results, in addition to confirming a T5 temperature dependence of the longitudinal relaxation rate at higher temperatures, in agreement with experimental observations, provide a theoretical background for modeling the spin-lattice relaxation at a wide range of temperatures where different temperature scalings might be expected.

  2. Guide to state-of-the-art electron devices

    CERN Document Server

    2013-01-01

    Concise, high quality and comparative overview of state-of-the-art electron device development, manufacturing technologies and applications Guide to State-of-the-Art Electron Devices marks the 60th anniversary of the IEEE Electron Devices Committee and the 35th anniversary of the IEEE Electron Devices Society, as such it defines the state-of-the-art of electron devices, as well as future directions across the entire field. Spans full range of electron device types such as photovoltaic devices, semiconductor manufacturing and VLSI technology and circuits, covered by IEEE Electron and Devices Society Contributed by internationally respected members of the electron devices community A timely desk reference with fully-integrated colour and a unique lay-out with sidebars to highlight the key terms Discusses the historical developments and speculates on future trends to give a more rounded picture of the topics covered A valuable resource R&D managers; engineers in the semiconductor industry; applied scientists...

  3. Field emission from individual multiwalled carbon nanotubes prepared in an electron microscope

    NARCIS (Netherlands)

    de Jonge, N.; van Druten, N.J.

    2003-01-01

    Individual multiwalled carbon nanotube field emitters were prepared in a scanning electron microscope. The angular current density, energy spectra, and the emission stability of the field-emitted electrons were measured. An estimate of the electron source brightness was extracted from the

  4. Electronic states in systems of reduced dimensionality

    International Nuclear Information System (INIS)

    Ulloa, S.E.

    1992-01-01

    This report briefly discusses the following research: magnetically modulated systems, inelastic magnetotunneling, ballistic transport review, screening in reduced dimensions, raman and electron energy loss spectroscopy; and ballistic quantum interference effects. (LSP)

  5. Electron states in semiconductor quantum dots

    International Nuclear Information System (INIS)

    Dhayal, Suman S.; Ramaniah, Lavanya M.; Ruda, Harry E.; Nair, Selvakumar V.

    2014-01-01

    In this work, the electronic structures of quantum dots (QDs) of nine direct band gap semiconductor materials belonging to the group II-VI and III-V families are investigated, within the empirical tight-binding framework, in the effective bond orbital model. This methodology is shown to accurately describe these systems, yielding, at the same time, qualitative insights into their electronic properties. Various features of the bulk band structure such as band-gaps, band curvature, and band widths around symmetry points affect the quantum confinement of electrons and holes. These effects are identified and quantified. A comparison with experimental data yields good agreement with the calculations. These theoretical results would help quantify the optical response of QDs of these materials and provide useful input for applications

  6. All electron ab initio investigations of the electronic states of the FeC molecule

    DEFF Research Database (Denmark)

    Shim, Irene; Gingerich, Karl A.

    1999-01-01

    The low lying electronic states of the molecule FeC have been investigated by performing all electron ab initio multi-configuration self-consistent-field (CASSCF) and multi reference configuration interaction (MRCI) calculations. The relativistic corrections for the one electron Darwin contact term...

  7. All Electron ab initio Investigations of the Electronic States of the MoN Molecule

    DEFF Research Database (Denmark)

    Shim, Irene; Gingerich, Karl A.

    1999-01-01

    The low lying electronic states of the molecule MoN have been investigated by performing all electron ab initio multi-configuration self-consistent-field (CASSCF) calculations. The relativistic corrections for the one electron Darwin contact term and the relativistic mass-velocity correction have...

  8. All-electron ab initio investigations of the electronic states of the NiC molecule

    DEFF Research Database (Denmark)

    Shim, Irene; Gingerich, Karl. A.

    1999-01-01

    The low-lying electronic states of NiC are investigated by all-electron ab initio multi-configuration self-consistent-field (CASSCF) calculations including relativistic corrections. The electronic structure of NiC is interpreted as perturbed antiferromagnetic couplings of the localized angular...

  9. Electron density measurement for steady state plasmas

    International Nuclear Information System (INIS)

    Kawano, Yasunori; Chiba, Shinichi; Inoue, Akira

    2000-01-01

    Electron density of a large tokamak has been measured successfully by the tangential CO 2 laser polarimeter developed in JT-60U. The tangential Faraday rotation angles of two different wavelength of 9.27 and 10.6 μm provided the electron density independently. Two-color polarimeter concept for elimination of Faraday rotation at vacuum windows is verified for the first time. A system stability for long time operation up to ∼10 hours is confirmed. A fluctuation of a signal baseline is observed with a period of ∼3 hours and an amplitude of 0.4 - 0.7deg. In order to improve the polarimeter, an application of diamond window for reduction of the Faraday rotation at vacuum windows and another two-color polarimeter concept for elimination of mechanical rotation component are proposed. (author)

  10. Steady States in SIRS Epidemical Model of Mobile Individuals

    International Nuclear Information System (INIS)

    Zhang Duanming; He Minhua; Yu Xiaoling; Pan Guijun; Sun Hongzhang; Su Xiangying; Sun Fan; Yin Yanping; Li Rui; Liu Dan

    2006-01-01

    We consider an epidemical model within socially interacting mobile individuals to study the behaviors of steady states of epidemic propagation in 2D networks. Using mean-field approximation and large scale simulations, we recover the usual epidemic behavior with critical thresholds δ c and p c below which infectious disease dies out. For the population density δ far above δ c , it is found that there is linear relationship between contact rate λ and the population density δ in the main. At the same time, the result obtained from mean-field approximation is compared with our numerical result, and it is found that these two results are similar by and large but not completely the same.

  11. Direct conversion of graphite into diamond through electronic excited states

    CERN Document Server

    Nakayama, H

    2003-01-01

    An ab initio total energy calculation has been performed for electronic excited states in diamond and rhombohedral graphite by the full-potential linearized augmented plane wave method within the framework of the local density approximation (LDA). First, calculations for the core-excited state in diamond have been performed to show that the ab initio calculations based on the LDA describe the wavefunctions in the electronic excited states as well as in the ground state quite well. Fairly good coincidence with both experimental data and theoretical prediction has been obtained for the lattice relaxation of the core exciton state. The results of the core exciton state are compared with nitrogen-doped diamond. Next, the structural stability of rhombohedral graphite has been investigated to examine the possibility of the transition into the diamond structure through electronic excited states. While maintaining the rhombohedral symmetry, rhombohedral graphite can be spontaneously transformed to cubic diamond. Tota...

  12. Transmission Electron Microscopy Study of Individual Carbon Nanotube Breakdown Caused by Joule Heating in Air

    DEFF Research Database (Denmark)

    Mølhave, Kristian; Gudnason, S.B.; Pedersen, Anders Tegtmeier

    2006-01-01

    We present repeated structural and electrical measurements on individual multiwalled carbon nanotubes, alternating between electrical measurements under ambient conditions and transmission electron microscopy (TEM). The multiwalled carbon nanotubes made by chemical vapor deposition were manipulated...

  13. Charging of Individual Micron-Size Interstellar/Planetary Dust Grains by Secondary Electron Emissions

    Science.gov (United States)

    Tankosic, D.; Abbas, M. M.

    2012-01-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with UV/X-ray radiation, as well as by electron/ion impact. Knowledge of physical and optical properties of individual dust grains is required for understanding of the physical and dynamical processes in space environments and the role of dust in formation of stellar and planetary systems. In this paper, we discuss experimental results on dust charging by electron impact, where low energy electrons are scattered or stick to the dust grains, thereby charging the dust grains negatively, and at sufficiently high energies the incident electrons penetrate the grain leading to excitation and emission of electrons referred to as secondary electron emission (SEE). Currently, very limited experimental data are available for charging of individual micron-size dust grains, particularly by low energy electron impact. Available theoretical models based on the Sternglass equation (Sternglass, 1954) are applicable for neutral, planar, and bulk surfaces only. However, charging properties of individual micron-size dust grains are expected to be different from the values measured on bulk materials. Our recent experimental results on individual, positively charged, micron-size lunar dust grains levitated in an electrodynamic balance facility (at NASA-MSFC) indicate that the SEE by electron impact is a complex process. The electron impact may lead to charging or discharging of dust grains depending upon the grain size, surface potential, electron energy, electron flux, grain composition, and configuration (e.g. Abbas et al, 2010). Here we discuss the complex nature of SEE charging properties of individual micron-size lunar dust grains and silica microspheres.

  14. Individual Low-Energy Toroidal Dipole State in Mg 24

    Science.gov (United States)

    Nesterenko, V. O.; Repko, A.; Kvasil, J.; Reinhard, P.-G.

    2018-05-01

    The low-energy dipole excitations in Mg 24 are investigated within the Skyrme quasiparticle random phase approximation for axial nuclei. The calculations with the force SLy6 reveal a remarkable feature: the lowest IπK =1-1 excitation (E =7.92 MeV ) in Mg 24 is a vortical toroidal state (TS) representing a specific vortex-antivortex realization of the well-known spherical Hill's vortex in a strongly deformed axial confinement. This is a striking example of an individual TS which can be much more easily discriminated in experiment than the toroidal dipole resonance embracing many states. The TS acquires the lowest energy due to the huge prolate axial deformation in Mg 24 . The result persists for different Skyrme parametrizations (SLy6, SVbas, SkM*). We analyze spectroscopic properties of the TS and its relation with the cluster structure of Mg 24 . Similar TSs could exist in other highly prolate light nuclei. They could serve as promising tests for various reactions to probe a vortical (toroidal) nuclear flow.

  15. Energetic disorder and exciton states of individual molecular rings

    International Nuclear Information System (INIS)

    Herman, Pavel; Barvik, Ivan; Zapletal, David

    2006-01-01

    Exciton states in molecular rings (resembling, e.g. the B850 ring from LH2 complexes of purple bacterium Rhodopseudomonas acidophila) with strong intermolecular interaction are still a question of interest [V. Sundstrom, T. Pullerits, R. van Grondelle, J. Phys. Chem. B 103 (1999) 2327]. In our theoretical model we use the ring of two-level systems, simulating, e.g., the bacteriochlorophylls B850. The dynamical aspects in ensemble of rings are reflected in optical line shapes of electronic transitions. The observed linewidths reflect the combined influence of different types of static and dynamic disorder. To avoid the broadening of lines due to ensemble averaging one uses the single-molecule spectroscopy technique to obtain a fluorescence-excitation spectrum. For zero disorder the exciton manifold features two non-degenerate and eight pairwise degenerate states. In the presence of energetic disorder the degeneracy of the exciton states is lifted and oscillator strength is redistributed among the exciton states. A satisfactory understanding of the nature of static disorder in light-harvesting systems has not been reached [S. Jang, S.F. Dempster, R.J. Silbey, J. Phys. Chem. B 105 (2001) 6655]. In the local site basis, there can be present static disorder in both diagonal and off-diagonal Hamiltonian matrix elements. Silbey et al. [J. Phys. Chem. B 105 (2001) 6655] pointed out several questions: is former enough or the latter should be included as well? If both are considered, then there remains a question about whether they are independent or correlated. The distribution of the energetic separation E(k=+/-1) and relative orientation of the transition-dipole moments has been recently investigated [S. Jang, et al., J. Phys. Chem. B 105 (2001) 6655; C. Hofmann, T.J. Aartsma, J. Koehler, Chem. Phys. Lett. 395 (2004) 373]. In our present contribution we have extended such a type of investigation to four models of noncorrelated static disorder: (A) Gaussian disorder in the

  16. Analysis of individual environmental particles using modern methods of electron microscopy and X-ray microanalysis

    International Nuclear Information System (INIS)

    Laskin, A.; Cowin, J.P.; Iedema, M.J.

    2006-01-01

    Understanding the composition of particles in the atmosphere is critical because of their health effects and their direct and indirect effects on radiative forcing, and hence on climate. In this manuscript, we demonstrate the utility of single particle off-line analysis to investigate the chemistry of individual atmospheric particles using modern, state-of-the-art electron microscopy and time-of-flight secondary ionization mass spectrometry techniques. We show that these methods provide specific, detailed data on particle composition, chemistry, morphology, phase and internal structure. This information is crucial for evaluating hygroscopic properties of aerosols, understanding aerosol aging and reactivity, and correlating the characteristics of aerosols with their optical properties. The manuscript presents a number of analytical advances in methods of electron probe particle analysis along with a brief review of a number of the research projects carried out in the authors' laboratory on the chemical characterization of environmental particles. The obtained data offers a rich set of qualitative and quantitative information on the particle chemistry, composition and the mechanisms of gas-particle interactions which are of high importance to atmospheric processes involving particulate matter and air pollution

  17. Equilibrium state of colliding electron beams

    Directory of Open Access Journals (Sweden)

    R. L. Warnock

    2003-10-01

    Full Text Available We study a nonlinear integral equation that is a necessary condition on the equilibrium phase-space distribution function of stored, colliding electron beams. It is analogous to the Haïssinski equation, being derived from Vlasov-Fokker-Planck theory, but is quite different in form. The equation is analyzed for the case of the Chao-Ruth model of the beam-beam interaction in 1 degree of freedom, a so-called strong-strong model with nonlinear beam-beam force. We prove the existence of a unique solution, for sufficiently small beam current, by an application of the implicit function theorem. We have not yet proved that this solution is positive, as would be required to establish existence of an equilibrium. There is, however, numerical evidence of a positive solution. We expect that our analysis can be extended to more realistic models.

  18. Effect of suprathermal electrons on the impurity ionization state

    International Nuclear Information System (INIS)

    Ochando, M A; Medina, F; Zurro, B; McCarthy, K J; Pedrosa, M A; Baciero, A; Rapisarda, D; Carmona, J M; Jimenez, D

    2006-01-01

    The effect of electron cyclotron resonance heating induced suprathermal electron tails on the ionization of iron impurities in magnetically confined plasmas is investigated. The behaviour of plasma emissivity immediately after injection provides evidence of a spatially localized 'shift' towards higher charge states of the impurity. Bearing in mind that the non-inductive plasma heating methods generate long lasting non-Maxwellian distribution functions, possible implications on the deduced impurity transport coefficients, when fast electrons are present, are discussed

  19. Electron beam melting state-of-the-art 1984

    International Nuclear Information System (INIS)

    Bakish, R.

    1984-01-01

    In 1984 electron beam melting and refining appear poised for an important new growth phase. The driving force for this phase is improved production economics made possible by technological advances. There is also a new and exciting growth application for electron beam melting: its use for surface properties beneficiation. This article is based in part on the content of the Conference on Electron Beam Melting and Refining, The State-of-the-Art 1983, held in November 1983 in Reno, Nevada

  20. The Role of Perceived Substitution and Individual Culture in the Adoption of Electronic Newspapers in Scandinavia

    DEFF Research Database (Denmark)

    Pogrebnyakov, Nicolai; Buchmann, Mikael

    2014-01-01

    Introduction:This paper explores the factors behind the adoption of electronic newspapers. Adoption is hypothesized to be driven by attributes of the electronic newspaper artefact (expressed by perceived substitution) and individual cultural characteristics of potential adopters. Perceived substi...... technology over another may lead to adoption, as well as to studies that investigate the role of individual cultural characteristics in the adoption of information and communication technologies....... was used to test hypotheses. Results: The results indicate that perceived substitution explains the adoption of electronic newspapers well, while most cultural factors did not show a significant effect on adoption. Conclusion: These results add to research on how perceived substitutive functionality of one...

  1. Imaging quasiperiodic electronic states in a synthetic Penrose tiling

    Science.gov (United States)

    Collins, Laura C.; Witte, Thomas G.; Silverman, Rochelle; Green, David B.; Gomes, Kenjiro K.

    2017-06-01

    Quasicrystals possess long-range order but lack the translational symmetry of crystalline solids. In solid state physics, periodicity is one of the fundamental properties that prescribes the electronic band structure in crystals. In the absence of periodicity and the presence of quasicrystalline order, the ways that electronic states change remain a mystery. Scanning tunnelling microscopy and atomic manipulation can be used to assemble a two-dimensional quasicrystalline structure mapped upon the Penrose tiling. Here, carbon monoxide molecules are arranged on the surface of Cu(111) one at a time to form the potential landscape that mimics the ionic potential of atoms in natural materials by constraining the electrons in the two-dimensional surface state of Cu(111). The real-space images reveal the presence of the quasiperiodic order in the electronic wave functions and the Fourier analysis of our results links the energy of the resonant states to the local vertex structure of the quasicrystal.

  2. Attosecond electron pulse trains and quantum state reconstruction in ultrafast transmission electron microscopy

    Science.gov (United States)

    Priebe, Katharina E.; Rathje, Christopher; Yalunin, Sergey V.; Hohage, Thorsten; Feist, Armin; Schäfer, Sascha; Ropers, Claus

    2017-12-01

    Ultrafast electron and X-ray imaging and spectroscopy are the basis for an ongoing revolution in the understanding of dynamical atomic-scale processes in matter. The underlying technology relies heavily on laser science for the generation and characterization of ever shorter pulses. Recent findings suggest that ultrafast electron microscopy with attosecond-structured wavefunctions may be feasible. However, such future technologies call for means to both prepare and fully analyse the corresponding free-electron quantum states. Here, we introduce a framework for the preparation, coherent manipulation and characterization of free-electron quantum states, experimentally demonstrating attosecond electron pulse trains. Phase-locked optical fields coherently control the electron wavefunction along the beam direction. We establish a new variant of quantum state tomography—`SQUIRRELS'—for free-electron ensembles. The ability to tailor and quantitatively map electron quantum states will promote the nanoscale study of electron-matter entanglement and new forms of ultrafast electron microscopy down to the attosecond regime.

  3. Molecular electronics with single molecules in solid-state devices

    DEFF Research Database (Denmark)

    Moth-Poulsen, Kasper; Bjørnholm, Thomas

    2009-01-01

    The ultimate aim of molecular electronics is to understand and master single-molecule devices. Based on the latest results on electron transport in single molecules in solid-state devices, we focus here on new insights into the influence of metal electrodes on the energy spectrum of the molecule...

  4. Surface-electronic-state effects in electron emission from the Be(0001) surface

    International Nuclear Information System (INIS)

    Archubi, C. D.; Gravielle, M. S.; Silkin, V. M.

    2011-01-01

    We study the electron emission produced by swift protons impinging grazingly on a Be(0001) surface. The process is described within a collisional formalism using the band-structure-based (BSB) approximation to represent the electron-surface interaction. The BSB model provides an accurate description of the electronic band structure of the solid and the surface-induced potential. Within this approach we derive both bulk and surface electronic states, with these latter characterized by a strong localization at the crystal surface. We found that such surface electronic states play an important role in double-differential energy- and angle-resolved electron emission probabilities, producing noticeable structures in the electron emission spectra.

  5. Surface-electronic-state effects in electron emission from the Be(0001) surface

    Energy Technology Data Exchange (ETDEWEB)

    Archubi, C. D. [Instituto de Astronomia y Fisica del Espacio, casilla de correo 67, sucursal 28, C1428EGA, Buenos Aires (Argentina); Gravielle, M. S. [Instituto de Astronomia y Fisica del Espacio, casilla de correo 67, sucursal 28, C1428EGA, Buenos Aires (Argentina); Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires (Argentina); Silkin, V. M. [Donostia International Physics Center, E-20018 San Sebastian (Spain); Departamento de Fisica de Materiales, Facultad de Ciencias Quimicas, Universidad del Pais Vasco, Apartado 1072, E-20080 San Sebastian (Spain); IKERBASQUE, Basque Foundation for Science, E-48011 Bilbao (Spain)

    2011-07-15

    We study the electron emission produced by swift protons impinging grazingly on a Be(0001) surface. The process is described within a collisional formalism using the band-structure-based (BSB) approximation to represent the electron-surface interaction. The BSB model provides an accurate description of the electronic band structure of the solid and the surface-induced potential. Within this approach we derive both bulk and surface electronic states, with these latter characterized by a strong localization at the crystal surface. We found that such surface electronic states play an important role in double-differential energy- and angle-resolved electron emission probabilities, producing noticeable structures in the electron emission spectra.

  6. D-state Rydberg electrons interacting with ultracold atoms

    Energy Technology Data Exchange (ETDEWEB)

    Krupp, Alexander Thorsten

    2014-10-02

    This thesis was established in the field of ultracold atoms where the interaction of highly excited D-state electrons with rubidium atoms was examined. This work is divided into two main parts: In the first part we study D-state Rydberg molecules resulting from the binding of a D-state Rydberg electron to a ground state rubidium atom. We show that we can address specific rovibrational molecular states by changing our laser detuning and thus create perfectly aligned axial or antialigned toroidal molecules, in good agreement with our theoretical calculations. Furthermore the influence of the electric field on the Rydberg molecules was investigated, creating novel states which show a different angular dependence and alignment. In the second part of this thesis we excite single D-state Rydberg electrons in a Bose-Einstein condensate. We study the lifetime of these Rydberg electrons, the change of the shape of our condensate and the atom losses in the condensate due to this process. Moreover, we observe quadrupolar shape oscillations of the whole condensate created by the consecutive excitation of Rydberg atoms and compare all results to previous S-state measurements. In the outlook we propose a wide range of further experiments including the proposal of imaging a single electron wavefunction by the imprint of its orbit into the Bose-Einstein condensate.

  7. Localized electronic states: the small radius potential approximation

    International Nuclear Information System (INIS)

    Steslicka, M.; Jurczyszyn, L.

    1984-09-01

    Using a quasi three-dimensional crystal model we investigate the localized electronic states, generated by the crystal surface covered by foreign atoms. Two such states are found in the first forbidden energy gap and, because of their localization properties, called the Tamm-like and adsorption-like states. Using the small radius potential approximation, the properties of both types of states were discussed in detail. (author)

  8. The electronic structure of core states under extreme compressions

    International Nuclear Information System (INIS)

    Straub, G.K.

    1992-01-01

    At normal density and for modest compressions, the electronic structure of a metal can be accurately described by treating the conduction electrons and their interactions with the usual methods of band theory. The core electrons remain essentially the same as for an isolated free atom and do not participate in the bonding forces responsible for creating a condensed phase. As the density increases, the core electrons begin to ''see'' one another as the overlap of the tails of wave functions can no longer be neglected. The electronic structure of the core electrons is responsible for an effective repulsive interaction that eventually becomes free-electron-like at very high compressions. The electronic structure of the interacting core electrons may be treated in a simple manner using the Atomic Surface Method (ASM). The ASM is a first-principles treatment of the electronic structure involving a rigorous integration of the Schroedinger equation within the atomic-sphere approximation. Solid phase wave functions are constructed from isolated atom wave functions and the band width W l and the center of gravity of the band C l are obtained from simple formulas. The ASM can also utilize analytic forms of the atomic wave functions and thus provide direct functional dependence of various aspects of the electronic structure. Of particular use in understanding the behavior of the core electrons, the ASM provides the ability to analytically determine the density dependence of the band widths and positions. The process whereby core states interact with one another is best viewed as the formation of narrow electron bands formed from atomic states. As the core-core overlap increases, the bands increase in width and mean energy. In Sec.3 this picture is further developed and from the ASM one obtains the analytic dependence on density of the relative motion of the different bands. Also in Sec. 3 is a discussion of the transition to free electron bands

  9. Adsorbates in a Box: Titration of Substrate Electronic States

    Science.gov (United States)

    Cheng, Zhihai; Wyrick, Jonathan; Luo, Miaomiao; Sun, Dezheng; Kim, Daeho; Zhu, Yeming; Lu, Wenhao; Kim, Kwangmoo; Einstein, T. L.; Bartels, Ludwig

    2010-08-01

    Nanoscale confinement of adsorbed CO molecules in an anthraquinone network on Cu(111) with a pore size of ≈4nm arranges the CO molecules in a shell structure that coincides with the distribution of substrate confined electronic states. Molecules occupy the states approximately in the sequence of rising electron energy. Despite the sixfold symmetry of the pore boundary itself, the adsorbate distribution adopts the threefold symmetry of the network-substrate system, highlighting the importance of the substrate even for such quasi-free-electron systems.

  10. Training Exit Survey (TES) Individual State and Tribe

    Data.gov (United States)

    U.S. Department of Health & Human Services — The TES Individual dataset contains information at the individual-level about the persons who attend a GLS funded training event. This dataset includes variables...

  11. Molecular electronics with single molecules in solid-state devices.

    Science.gov (United States)

    Moth-Poulsen, Kasper; Bjørnholm, Thomas

    2009-09-01

    The ultimate aim of molecular electronics is to understand and master single-molecule devices. Based on the latest results on electron transport in single molecules in solid-state devices, we focus here on new insights into the influence of metal electrodes on the energy spectrum of the molecule, and on how the electron transport properties of the molecule depend on the strength of the electronic coupling between it and the electrodes. A variety of phenomena are observed depending on whether this coupling is weak, intermediate or strong.

  12. Communication: Electronic flux induced by crossing the transition state

    Science.gov (United States)

    Jia, Dongming; Manz, Jörn; Yang, Yonggang

    2018-01-01

    We present a new effect of chemical reactions, e.g., isomerizations, that occurs when the reactants pass along the transition state, on the way to products. It is based on the well-known fact that at the transition state, the electronic structure of one isomer changes to the other. We discover that this switch of electronic structure causes a strong electronic flux that is well distinguishable from the usual flux of electrons that travel with the nuclei. As a simple but clear example, the effect is demonstrated here for bond length isomerization of Na2 (21Σu+), with adiabatic crossing the barrier between the inner and outer wells of the double minimum potential that support different "Rydberg" and "ionic" type electronic structures, respectively.

  13. Energy of ground state of laminar electron-hole liquid

    International Nuclear Information System (INIS)

    Andryushin, E.A.

    1976-01-01

    The problem of a possible existence of metal electron-hole liquid in semiconductors is considered. The calculation has been carried out for the following model: two parallel planes are separated with the distance on one of the planes electrons moving, on the other holes doing. Transitions between the planes are forbidden. The density of particles for both planes is the same. The energy of the ground state and correlation functions for such electron-and hole system are calculated. It is shown that the state of a metal liquid is more advantageous against the exciton gas. For the mass ratio of electrons and holes, msub(e)/msub(h) → 0 a smooth rearrangement of the system into a state with ordered heavy particles is observed

  14. Electronically excited negative ion resonant states in chloroethylenes

    Energy Technology Data Exchange (ETDEWEB)

    Khvostenko, O.G., E-mail: khv@mail.ru; Lukin, V.G.; Tuimedov, G.M.; Khatymova, L.Z.; Kinzyabulatov, R.R.; Tseplin, E.E.

    2015-02-15

    Highlights: • Several novel dissociative negative ion channels were revealed in chloroethylenes. • The electronically excited resonant states were recorded in all chloroethylenes under study. • The states were assigned to the inter-shell types, but not to the core-excited Feshbach one. - Abstract: The negative ion mass spectra of the resonant electron capture by molecules of 1,1-dichloroethylene, 1,2-dichloroethylene-cis, 1,2-dichloroethylene-trans, trichloroethylene and tetrachloroethylene have been recorded in the 0–12 eV range of the captured electron energy using static magnetic sector mass spectrometer modified for operation in the resonant electron capture regime. As a result, several novel low-intensive dissociation channels were revealed in the compounds under study. Additionally, the negative ion resonant states were recorded at approximately 3–12 eV, mostly for the first time. These resonant states were assigned to the electronically excited resonances of the inter-shell type by comparing their energies with those of the parent neutral molecules triplet and singlet electronically excited states known from the energy-loss spectra obtained by previous studies.

  15. Electron momentum spectroscopy of aniline taking account of nuclear dynamics in the initial electronic ground state

    International Nuclear Information System (INIS)

    Farasat, M; Golzan, M M; Shojaei, S H R; Morini, F; Deleuze, M S

    2016-01-01

    The electronic structure, electron binding energy spectrum and (e, 2e) momentum distributions of aniline have been theoretically predicted at an electron impact energy of 1.500 keV on the basis of Born–Oppenheimer molecular dynamical simulations, in order to account for thermally induced nuclear motions in the initial electronic ground state. Most computed momentum profiles are rather insensitive to thermally induced alterations of the molecular structure, with the exception of the profiles corresponding to two ionization bands at electron binding energies comprised between ∼10.0 and ∼12.0 eV (band C) and between ∼16.5 and ∼20.0 eV (band G). These profiles are found to be strongly influenced by nuclear dynamics in the electronic ground state, especially in the low momentum region. The obtained results show that thermal averaging smears out most generally the spectral fingerprints that are induced by nitrogen inversion. (paper)

  16. Direct Observation of Individual Charges and Their Dynamics on Graphene by Low-Energy Electron Holography.

    Science.gov (United States)

    Latychevskaia, Tatiana; Wicki, Flavio; Longchamp, Jean-Nicolas; Escher, Conrad; Fink, Hans-Werner

    2016-09-14

    Visualizing individual charges confined to molecules and observing their dynamics with high spatial resolution is a challenge for advancing various fields in science, ranging from mesoscopic physics to electron transfer events in biological molecules. We show here that the high sensitivity of low-energy electrons to local electric fields can be employed to directly visualize individual charged adsorbates and to study their behavior in a quantitative way. This makes electron holography a unique probing tool for directly visualizing charge distributions with a sensitivity of a fraction of an elementary charge. Moreover, spatial resolution in the nanometer range and fast data acquisition inherent to lens-less low-energy electron holography allows for direct visual inspection of charge transfer processes.

  17. State and Individuality: The New Tendencies of the State Action on Behavior

    Directory of Open Access Journals (Sweden)

    Marina Fischer Monteiro de Araujo

    2016-11-01

    Full Text Available There are several teories that seek to analyse and relate the state´s action and the conservation of individuality. With the resumption of paternalistic theories, represented by Coercive Paternalism, by Sarah Conly, and the Libertarian Paternalism by Cass Sustein and Richard Thaler, the world started to give more attention to factors such as de boundaries of tradicional sciences. This work aims to undestand better the paternalistic movement and provide examples of implementations in the brazilian reality.

  18. X-ray imaging and spectroscopy of individual cobalt nanoparticles using photoemission electron microscopy

    International Nuclear Information System (INIS)

    Fraile Rodriguez, A.; Nolting, F.; Bansmann, J.; Kleibert, A.; Heyderman, L.J.

    2007-01-01

    Photoemission electron microscopy (PEEM) was employed for X-ray imaging and absorption spectroscopy of individual cobalt nanoparticles as small as 8 nm grown using an arc ion cluster source. Using lithographic markers on the samples we were able to identify the same particles with PEEM and scanning electron microscopy. Significant variations in the shape of the X-ray absorption spectra between different cobalt particles were detected. Furthermore, our data suggest that distinctive spectral information about the individual particles, such as the quenching of oxide-related features and changes in the cobalt L 3 -edge intensity, cancel out and cannot be detected in the measurement over an ensemble of particles

  19. Kentucky's Individualized Kindergartens: A State Network Design for Early Intervention.

    Science.gov (United States)

    Bright, B.; Cansler, D. P.

    The KIK (Kentucky Individualized Kindergartens) project, a collaborative project between Kentucky's Department of Education and the Chapel Hill (NC) Training-Outreach project, is designed to serve high risk children. KIK provides early identification of high risk kindergarteners, development of individualized education programs, and implementation…

  20. Dynamic tunneling force microscopy for characterizing electronic trap states in non-conductive surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R.; Williams, C. C., E-mail: clayton@physics.utah.edu [Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112 (United States)

    2015-09-15

    Dynamic tunneling force microscopy (DTFM) is a scanning probe technique for real space mapping and characterization of individual electronic trap states in non-conductive films with atomic scale spatial resolution. The method is based upon the quantum mechanical tunneling of a single electron back and forth between a metallic atomic force microscopy tip and individual trap states in completely non-conducting surface. This single electron shuttling is measured by detecting the electrostatic force induced on the probe tip at the shuttling frequency. In this paper, the physical basis for the DTFM method is unfolded through a physical model and a derivation of the dynamic tunneling signal as a function of several experimental parameters is shown. Experimental data are compared with the theoretical simulations, showing quantitative consistency and verifying the physical model used. The experimental system is described and representative imaging results are shown.

  1. Photoionization of furan from the ground and excited electronic states.

    Science.gov (United States)

    Ponzi, Aurora; Sapunar, Marin; Angeli, Celestino; Cimiraglia, Renzo; Došlić, Nađa; Decleva, Piero

    2016-02-28

    Here we present a comparative computational study of the photoionization of furan from the ground and the two lowest-lying excited electronic states. The study aims to assess the quality of the computational methods currently employed for treating bound and continuum states in photoionization. For the ionization from the ground electronic state, we show that the Dyson orbital approach combined with an accurate solution of the continuum one particle wave functions in a multicenter B-spline basis, at the density functional theory (DFT) level, provides cross sections and asymmetry parameters in excellent agreement with experimental data. On the contrary, when the Dyson orbitals approach is combined with the Coulomb and orthogonalized Coulomb treatments of the continuum, the results are qualitatively different. In excited electronic states, three electronic structure methods, TDDFT, ADC(2), and CASSCF, have been used for the computation of the Dyson orbitals, while the continuum was treated at the B-spline/DFT level. We show that photoionization observables are sensitive probes of the nature of the excited states as well as of the quality of excited state wave functions. This paves the way for applications in more complex situations such as time resolved photoionization spectroscopy.

  2. Stability of the antiferromagnetic state in the electron doped iridates

    Science.gov (United States)

    Bhowal, Sayantika; Moradi Kurdestany, Jamshid; Satpathy, Sashi

    2018-06-01

    Iridates such as Sr2IrO4 are of considerable interest owing to the formation of the Mott insulating state driven by a large spin–orbit coupling. However, in contrast to the expectation from the Nagaoka theorem that a single doped hole or electron destroys the anti-ferromagnetic (AFM) state of the half-filled Hubbard model in the large U limit, the anti-ferromagnetism persists in the doped Iridates for a large dopant concentration beyond half-filling. With a tight-binding description of the relevant states by the third-neighbor (t 1, t 2, t 3, U) Hubbard model on the square lattice, we examine the stability of the AFM state to the formation of a spin spiral state in the strong coupling limit. The third-neighbor interaction t 3 is important for the description of the Fermi surface of the electron doped system. A phase diagram in the parameter space is obtained for the regions of stability of the AFM state. Our results qualitatively explain the robustness of the AFM state in the electron doped iridate (such as Sr2‑x La x IrO4), observed in many experiments, where the AFM state continues to be stable until a critical dopant concentration.

  3. Electron capture to autoionizing states of multiply charged ions

    International Nuclear Information System (INIS)

    Mack, E.M.

    1987-01-01

    The present thesis investigates electron capture reactions resulting from slow collisions (V q+ ) and neutral gas targets (B). The energy spectra of the emitted electrons are measured; detection angle is 50 0 . Mainly, autoionizing double capture resulting from collisions with two-electron targets (He, H 2 ) is studied; then, the emitted electrons stem from doubly excited projectile states. The projectiles used are bare C 6+ , the H-like and He-like ions of C, N and O, He-like Ne 8+ and Ne-like Ar 8+ . Excited metastable projectiles used are C 5+ (2s), He-like projectiles A q+ (1s2s 3 S) and Ar 8+ (...2p 5 3s). Comparison is made with the predictions of a recently proposed extended classical barrier model, that was developed in connection with the work. This model assumes sequential capture of the electrons ('two-step' process); it predicts the realized binding enegies of the captured electrons - which may be directly determined from the autoionization spectra using only the projectile charge, the ionization potentials of the target and the collision velocity as parameters. No adjustable parameter enters into the calculations. The term energies and decay modes of the highly excited product ions themselves are studied. Generally, the autoionizing decay of these states is found to proceed preferentially to the directly adjacent lower singly excited state. Experimental evidence is presented, that triply excited states decay by successive emission of two electrons, whenever this is energetically possible. Finally, the L-MM decay in few-electron systems is considered. 314 refs.; 96 figs.; 29 tabs

  4. Integral cross sections for electron impact excitation of vibrational and electronic states in phenol

    Energy Technology Data Exchange (ETDEWEB)

    Neves, R. F. C. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001 (Australia); Instituto Federal do Sul de Minas Gerais, Campus Poços de Caldas, Minas Gerais (Brazil); Departamento de Física, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, Minas Gerais (Brazil); Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001 (Australia); Lopes, M. C. A. [Departamento de Física, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora, Minas Gerais (Brazil); Blanco, F. [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, 28040 Madrid (Spain); García, G. [Instituto de Física Fundamental, CSIC, Serrano 113-bis, 28006 Madrid (Spain); Ratnavelu, K. [Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Brunger, M. J., E-mail: Michael.Brunger@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-05-21

    We report on measurements of integral cross sections (ICSs) for electron impact excitation of a series of composite vibrational modes and electronic-states in phenol, where the energy range of those experiments was 15–250 eV. There are currently no other results against which we can directly compare those measured data. We also report results from our independent atom model with screened additivity rule correction computations, namely, for the inelastic ICS (all discrete electronic states and neutral dissociation) and the total ionisation ICS. In addition, for the relevant dipole-allowed excited electronic states, we also report f-scaled Born-level and energy-corrected and f-scaled Born-level (BEf-scaled) ICS. Where possible, our measured and calculated ICSs are compared against one another with the general level of accord between them being satisfactory to within the measurement uncertainties.

  5. Electron momentum spectroscopy of the core state of solid carbon

    International Nuclear Information System (INIS)

    Caprari, R.S.; Clark, S.A.C.; McCarthy, I.E.; Storer, P.J.; Vos, M.; Weigold, E.

    1994-08-01

    Electron momentum spectroscopy (binary encounter (e,2e)) experimental results are presented for the core state of an amorphous carbon allotrope. The (e,2e) cross section has two identifiable regions. One is a narrow energy width 'core band peak' that does not disperse with momentum. At higher binding energies there is an energy diffuse 'multiple scattering continuum', which is a consequence of (e,2e) collisions with core electrons that are accompanied by inelastic scattering of one or more of the incoming or outgoing electrons. Comparisons of experimental momentum distributions with the Hartree-Fock atomic carbon ls orbital are presented for both regions. 16 refs., 4 figs

  6. Dipole-bound states as doorways in (dissociative) electron attachment

    International Nuclear Information System (INIS)

    Sommerfeld, Thomas

    2005-01-01

    This communication starts with a comparison of dissociative recombination and dissociative attachment placing emphasis on the role of resonances as reactive intermediates. The main focus is then the mechanism of electron attachment to polar molecules at very low energies (100 meV). The scheme considered consists of two steps: First, an electron is captured in a diffuse dipole-bound state depositing its energy in the vibrational degrees of freedom, in other words, a vibrational Feshbach resonance is formed. Then, owing to the coupling with a valence state, the electron is transferred into a compact valence orbital, and depending on the electron affinities of the valence state and possible dissociation products, as well as on the details of the intramolecular redistribution of vibrational energy, long-lived anions can be generated or dissociation reactions can be initiated. The key property in this context is the electronic coupling strength between the diffuse dipole-bound and the compact valence states. We describe how the coupling strength can be extracted from ab initio data, and present results for Nitromethane, Uracil and Cyanoacetylene

  7. Electron-nuclear magnetic resonance in the inverted state

    International Nuclear Information System (INIS)

    Ignatchenko, V.A.; Tsifrinovich, V.I.

    1975-01-01

    The paper considers the susceptibility of the electron-nucleus system of a ferromagnet when nuclear magnetization is inverted with respect to the hyperfine field direction. The inverted state is a situation in which nuclear magnetization is turned through π relative to its equilibrium orientation, whereas electron magnetization is in an equilibrium state with respect to an external magnetic field. The consideration is carried out for a thin plate magnetized in its plane. Amplification of a weak radiofrequency signal can be attained under the fulfilment of an additional inequality relating the interaction frequency with electron and nuclear relaxation parameters. The gain may exceed the gain for an inverted nuclear system in magnetically disordered substances. In the range of strong interaction between the frequencies of ferromagnetic (FMR) and nuclear magnetic (NMR) resonances the electron-nuclear magnetic resonance (ENMR) spectrum possesses a fine structure which is inverse to that obtained for the ENMR spectrum in a normal state. The inverted state ENMR line shape is analysed in detail for the case of so weak HF fields that the relaxation conditions may be regarded as stationary. The initial (linear) stages of a forced transient process arising in an electron-nuclear system under the effect of a strong HF field are briefly analysed

  8. Leaky electronic states for photovoltaic photodetectors based on asymmetric superlattices

    Science.gov (United States)

    Penello, Germano Maioli; Pereira, Pedro Henrique; Pires, Mauricio Pamplona; Sivco, Deborah; Gmachl, Claire; Souza, Patricia Lustoza

    2018-01-01

    The concept of leaky electronic states in the continuum is used to achieve room temperature operation of photovoltaic superlattice infrared photodetectors. A structural asymmetric InGaAs/InAlAs potential profile is designed to create states in the continuum with the preferential direction for electron extraction and, consequently, to obtain photovoltaic operation at room temperature. Due to the photovoltaic operation and virtual increase in the bandoffset, the device presents both low dark current and low noise. The Johnson noise limited specific detectivity reaches values as high as 1.4 × 1011 Jones at 80 K. At 300 K, the detectivity obtained is 7.0 × 105 Jones.

  9. Development of Communication Strategies for the Marketing of Electronic Banking Services for Individuals

    Directory of Open Access Journals (Sweden)

    Dunas Natalia V.

    2017-03-01

    Full Text Available The main aim of the article is to study the trends in the development of communication strategies for the marketing of electronic banking services for individuals by studying the foreign experience in Digital Banking, as well as the situation in the Ukrainian banking market. There offered a comparative characteristic of banking systems of electronic banking services for clients with the purpose of working out flexible methodological approaches for the development of marketing communication strategies for remote client servicing. The characteristic features of electronic banking services and technologies in Ukraine are determined. Comparative evaluation of positive aspects and risks of remote electronic banking systems for banks as well as their client segment is conducted. Analytical aspects of the sociological survey of European banks regarding the selection of the most important priorities of the marketing strategies of financial institutions for 2017 are presented. Also the main factors determining the development of marketing communications of banks and their clients in the field of electronic payments both in Ukraine and abroad are identified. Modern directions of development of communication strategies of marketing of electronic banking services for individuals in Ukraine are proposed.

  10. 3D structure of individual nanocrystals in solution by electron microscopy

    Science.gov (United States)

    Park, Jungwon; Elmlund, Hans; Ercius, Peter; Yuk, Jong Min; Limmer, David T.; Chen, Qian; Kim, Kwanpyo; Han, Sang Hoon; Weitz, David A.; Zettl, A.; Alivisatos, A. Paul

    2015-07-01

    Knowledge about the synthesis, growth mechanisms, and physical properties of colloidal nanoparticles has been limited by technical impediments. We introduce a method for determining three-dimensional (3D) structures of individual nanoparticles in solution. We combine a graphene liquid cell, high-resolution transmission electron microscopy, a direct electron detector, and an algorithm for single-particle 3D reconstruction originally developed for analysis of biological molecules. This method yielded two 3D structures of individual platinum nanocrystals at near-atomic resolution. Because our method derives the 3D structure from images of individual nanoparticles rotating freely in solution, it enables the analysis of heterogeneous populations of potentially unordered nanoparticles that are synthesized in solution, thereby providing a means to understand the structure and stability of defects at the nanoscale.

  11. Nanoparticle imaging. 3D structure of individual nanocrystals in solution by electron microscopy.

    Science.gov (United States)

    Park, Jungwon; Elmlund, Hans; Ercius, Peter; Yuk, Jong Min; Limmer, David T; Chen, Qian; Kim, Kwanpyo; Han, Sang Hoon; Weitz, David A; Zettl, A; Alivisatos, A Paul

    2015-07-17

    Knowledge about the synthesis, growth mechanisms, and physical properties of colloidal nanoparticles has been limited by technical impediments. We introduce a method for determining three-dimensional (3D) structures of individual nanoparticles in solution. We combine a graphene liquid cell, high-resolution transmission electron microscopy, a direct electron detector, and an algorithm for single-particle 3D reconstruction originally developed for analysis of biological molecules. This method yielded two 3D structures of individual platinum nanocrystals at near-atomic resolution. Because our method derives the 3D structure from images of individual nanoparticles rotating freely in solution, it enables the analysis of heterogeneous populations of potentially unordered nanoparticles that are synthesized in solution, thereby providing a means to understand the structure and stability of defects at the nanoscale. Copyright © 2015, American Association for the Advancement of Science.

  12. The electron transport problem sampling by Monte Carlo individual collision technique

    International Nuclear Information System (INIS)

    Androsenko, P.A.; Belousov, V.I.

    2005-01-01

    The problem of electron transport is of most interest in all fields of the modern science. To solve this problem the Monte Carlo sampling has to be used. The electron transport is characterized by a large number of individual interactions. To simulate electron transport the 'condensed history' technique may be used where a large number of collisions are grouped into a single step to be sampled randomly. Another kind of Monte Carlo sampling is the individual collision technique. In comparison with condensed history technique researcher has the incontestable advantages. For example one does not need to give parameters altered by condensed history technique like upper limit for electron energy, resolution, number of sub-steps etc. Also the condensed history technique may lose some very important tracks of electrons because of its limited nature by step parameters of particle movement and due to weakness of algorithms for example energy indexing algorithm. There are no these disadvantages in the individual collision technique. This report presents some sampling algorithms of new version BRAND code where above mentioned technique is used. All information on electrons was taken from Endf-6 files. They are the important part of BRAND. These files have not been processed but directly taken from electron information source. Four kinds of interaction like the elastic interaction, the Bremsstrahlung, the atomic excitation and the atomic electro-ionization were considered. In this report some results of sampling are presented after comparison with analogs. For example the endovascular radiotherapy problem (P2) of QUADOS2002 was presented in comparison with another techniques that are usually used. (authors)

  13. The electron transport problem sampling by Monte Carlo individual collision technique

    Energy Technology Data Exchange (ETDEWEB)

    Androsenko, P.A.; Belousov, V.I. [Obninsk State Technical Univ. of Nuclear Power Engineering, Kaluga region (Russian Federation)

    2005-07-01

    The problem of electron transport is of most interest in all fields of the modern science. To solve this problem the Monte Carlo sampling has to be used. The electron transport is characterized by a large number of individual interactions. To simulate electron transport the 'condensed history' technique may be used where a large number of collisions are grouped into a single step to be sampled randomly. Another kind of Monte Carlo sampling is the individual collision technique. In comparison with condensed history technique researcher has the incontestable advantages. For example one does not need to give parameters altered by condensed history technique like upper limit for electron energy, resolution, number of sub-steps etc. Also the condensed history technique may lose some very important tracks of electrons because of its limited nature by step parameters of particle movement and due to weakness of algorithms for example energy indexing algorithm. There are no these disadvantages in the individual collision technique. This report presents some sampling algorithms of new version BRAND code where above mentioned technique is used. All information on electrons was taken from Endf-6 files. They are the important part of BRAND. These files have not been processed but directly taken from electron information source. Four kinds of interaction like the elastic interaction, the Bremsstrahlung, the atomic excitation and the atomic electro-ionization were considered. In this report some results of sampling are presented after comparison with analogs. For example the endovascular radiotherapy problem (P2) of QUADOS2002 was presented in comparison with another techniques that are usually used. (authors)

  14. Electronic states of graphene nanoribbons and analytical solutions

    Directory of Open Access Journals (Sweden)

    Katsunori Wakabayashi, Ken-ichi Sasaki, Takeshi Nakanishi and Toshiaki Enoki

    2010-01-01

    Full Text Available Graphene is a one-atom-thick layer of graphite, where low-energy electronic states are described by the massless Dirac fermion. The orientation of the graphene edge determines the energy spectrum of π-electrons. For example, zigzag edges possess localized edge states with energies close to the Fermi level. In this review, we investigate nanoscale effects on the physical properties of graphene nanoribbons and clarify the role of edge boundaries. We also provide analytical solutions for electronic dispersion and the corresponding wavefunction in graphene nanoribbons with their detailed derivation using wave mechanics based on the tight-binding model. The energy band structures of armchair nanoribbons can be obtained by making the transverse wavenumber discrete, in accordance with the edge boundary condition, as in the case of carbon nanotubes. However, zigzag nanoribbons are not analogous to carbon nanotubes, because in zigzag nanoribbons the transverse wavenumber depends not only on the ribbon width but also on the longitudinal wavenumber. The quantization rule of electronic conductance as well as the magnetic instability of edge states due to the electron–electron interaction are briefly discussed.

  15. State surveillance as a threat to personal security of individuals

    Directory of Open Access Journals (Sweden)

    Sławomir Czapnik

    2015-12-01

    Full Text Available Changes in modern society are crucial to individuals. Article starts with analysis of control in nowadays societies. Then author tries to understand useful categories, as "Panopticon", "ban-opticon" and "synopticon". Last part is focused on stete surveillance, i.e. surveillance by American National Security Agency.

  16. In situ electron backscattered diffraction of individual GaAs nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Prikhodko, S.V. [Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 (United States)], E-mail: sergey@seas.ucla.edu; Sitzman, S. [Oxford Instruments America, Concord, MA 01742 (United States); Gambin, V. [Northrop Grumman Space Technology, Redondo Beach, CA 90278 (United States); Kodambaka, S. [Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 (United States)

    2008-12-15

    We suggest and demonstrate that electron backscattered diffraction, a scanning electron microscope-based technique, can be used for non-destructive structural and morphological characterization of statistically significant number of nanowires in situ on their growth substrate. We obtain morphological, crystal phase, and crystal orientation information of individual GaAs nanowires in situ on the growth substrate GaAs(1 1 1) B. Our results, verified using transmission electron microscopy and selected area electron diffraction analyses of the same set of wires, indicate that most wires possess a wurtzite structure with a high density of thin structural defects aligned normal to the wire growth axis, while others grow defect-free with a zincblende structure. The demonstrated approach is general, applicable to other material systems, and is expected to provide important insights into the role of substrate structure on nanowire structure on nanowire crystallinity and growth orientation.

  17. Trapped electronic states in YAG crystal excited by femtosecond radiation

    Energy Technology Data Exchange (ETDEWEB)

    Zavedeev, E.V.; Kononenko, V.V.; Konov, V.I. [General Physics Institute of RAS, Moscow (Russian Federation); National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow (Russian Federation)

    2017-07-15

    The excitation of an electronic subsystem of an yttrium aluminum garnet by 800 nm femtosecond radiation was studied theoretically and experimentally. The spatio-temporal dynamics of the refractive index (n) inside the beam waist was explored by means of the pump-probe interferometric technique with a submicron resolution. The observed increase in n indicated the formation of bound electronic states relaxed for ∝ 150 ps. We showed that the experimental data agreed with the computational simulation based on the numerical solution of the nonlinear Schroedinger equation only if these transient states were considered to arise from a direct light-induced process but not from the decay of radiatively generated free-electron-hole pairs. (orig.)

  18. Photoemission electronic states of epitaxially grown magnetite films

    International Nuclear Information System (INIS)

    Zalecki, R.; Kolodziejczyk, A.; Korecki, J.; Spiridis, N.; Zajac, M.; Kozlowski, A.; Kakol, Z.; Antolak, D.

    2007-01-01

    The valence band photoemission spectra of epitaxially grown 300 A single crystalline magnetite films were measured by the angle-resolved ultraviolet photoemission spectroscopy (ARUPS) at 300 K. The samples were grown either on MgO(0 0 1) (B termination) or on (0 0 1) Fe (iron-rich A termination), thus intentionally presenting different surface stoichiometry, i.e. also different surface electronic states. Four main features of the electron photoemission at about -1.0, -3.0, -5.5 and -10.0 eV below a chemical potential show systematic differences for two terminations; this difference depends on the electron outgoing angle. Our studies confirm sensitivity of angle resolved PES technique on subtleties of surface states

  19. Ground-state electronic structure of actinide monocarbides and mononitrides

    DEFF Research Database (Denmark)

    Petit, Leon; Svane, Axel; Szotek, Z.

    2009-01-01

    The self-interaction corrected local spin-density approximation is used to investigate the ground-state valency configuration of the actinide ions in the actinide monocarbides, AC (A=U,Np,Pu,Am,Cm), and the actinide mononitrides, AN. The electronic structure is characterized by a gradually increa...

  20. Electron beam charge state amplifier (EBQA)--a conceptual evaluation

    International Nuclear Information System (INIS)

    Dooling, J. C.

    1998-01-01

    A concept is presented for stripping low-energy, radioactive ions from 1+ to higher charge states. Referred to as an Electron Beam Charge State Amplifier (EBQA), this device accepts a continuous beam of singly-charged, radioactive ions and passes them through a high-density electron beam confined by a solenoidal magnetic field. Singly-charged ions may be extracted from standard Isotope-Separator-Online (ISOL) sources. An EBQA is potentially useful for increasing the charge state of ions prior to injection into post-acceleration stages at ISOL radioactive beam facilities. The stripping efficiency from q=1+ to 2+ (η 12 ) is evaluated as a function of electron beam radius at constant current with solenoid field, injected ion energy, and ion beam emittance used as parameters. Assuming a 5 keV, 1 A electron beam, η 12 = 0.38 for 0.1 keV, 132 Xe ions passing through an 8 Tesla solenoid, 1 m in length. Multi-pass configurations to achieve 3+ or 4+ charge states are also conceivable. The calculated efficiencies depend inversely on the initial ion beam emittances. The use of a helium-buffer-gas, ion-guide stage to improve the brightness of the 1+ beams [1] may enhance the performance of an EBQA

  1. Influence of scattering processes on electron quantum states in nanowires

    Directory of Open Access Journals (Sweden)

    Pozdnyakov Dmitry

    2007-01-01

    Full Text Available AbstractIn the framework of quantum perturbation theory the self-consistent method of calculation of electron scattering rates in nanowires with the one-dimensional electron gas in the quantum limit is worked out. The developed method allows both the collisional broadening and the quantum correlations between scattering events to be taken into account. It is an alternativeper seto the Fock approximation for the self-energy approach based on Green’s function formalism. However this approach is free of mathematical difficulties typical to the Fock approximation. Moreover, the developed method is simpler than the Fock approximation from the computational point of view. Using the approximation of stable one-particle quantum states it is proved that the electron scattering processes determine the dependence of electron energy versus its wave vector.

  2. Foucault's Pendulum, Analog for an Electron Spin State

    Science.gov (United States)

    Linck, Rebecca

    2012-11-01

    The classical Lagrangian that describes the coupled oscillations of Foucault's pendulum presents an interesting analog to an electron's spin state in an external magnetic field. With a simple modification, this classical Lagrangian yields equations of motion that directly map onto the Schrodinger-Pauli Equation. This analog goes well beyond the geometric phase, reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.

  3. Two Electron States in a Quantum Ring on a Sphere

    International Nuclear Information System (INIS)

    Kazaryan, Eduard M.; Shahnazaryan, Vanik A.; Sarkisyan, Hayk A.

    2014-01-01

    Two electron states in a quantum ring on a spherical surface are discussed. The problem is discussed within the frameworks of Russell–Saunders coupling scheme, that is, the spin–orbit coupling is neglected. Treating Coulomb interaction as a perturbation, the energy correction for different states is calculated. The dependence of the Coulomb interaction energy on external polar boundary angle of quantum ring is obtained. In analogue with the helium atom the concept of states exchange time is introduced, and its dependence on geometrical parameters of the ring is shown. (author)

  4. Foucault's pendulum, a classical analog for the electron spin state

    Science.gov (United States)

    Linck, Rebecca A.

    Spin has long been regarded as a fundamentally quantum phenomena that is incapable of being described classically. To bridge the gap and show that aspects of spin's quantum nature can be described classically, this work uses a classical Lagrangian based on the coupled oscillations of Foucault's pendulum as an analog for the electron spin state in an external magnetic field. With this analog it is possible to demonstrate that Foucault's pendulum not only serves as a basis for explaining geometric phase, but is also a basis for reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured electron spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.

  5. Assessing State Vocational Rehabilitation Performance in Serving Individuals with Disability.

    Science.gov (United States)

    Lewis, Darrell R.; Johnson, David R.; Scholl, Steven R.

    2003-01-01

    This paper reports the use of multi-attribute utility analysis for evaluating the goals and services of a state vocational rehabilitation agency. Uses included: (1) identification and clarification of agency goals and services; (2) engagement of stakeholders in the determination of measurable attributes of these goals; and (3) use of…

  6. Chemical modulation of electronic structure at the excited state

    Science.gov (United States)

    Li, F.; Song, C.; Gu, Y. D.; Saleem, M. S.; Pan, F.

    2017-12-01

    Spin-polarized electronic structures are the cornerstone of spintronics, and have thus attracted a significant amount of interest; in particular, researchers are looking into how to modulate the electronic structure to enable multifunctional spintronics applications, especially in half-metallic systems. However, the control of the spin polarization has only been predicted in limited two-dimensional systems with spin-polarized Dirac structures and is difficult to achieve experimentally. Here, we report the modulation of the electronic structure in the light-induced excited state in a typical half-metal, L a1 /2S r1 /2Mn O3 -δ . According to the spin-transport measurements, there appears a light-induced increase in magnetoresistance due to the enhanced spin scattering, which is closely associated with the excited spin polarization. Strikingly, the light-induced variation can be enhanced via alcohol processing and reduced by oxygen annealing. X-ray photoelectron spectroscopy measurements show that in the chemical process, a redox reaction occurs with a change in the valence of Mn. Furthermore, first-principles calculations reveal that the change in the valence of Mn alters the electronic structure and consequently modulates the spin polarization in the excited state. Our findings thus report a chemically tunable electronic structure, demonstrating interesting physics and the potential for multifunctional applications and ultrafast spintronics.

  7. Single-electron states near a current-carrying core

    International Nuclear Information System (INIS)

    Masale, M.

    2004-01-01

    The energy spectrum of an electron confined near a current-carrying core is obtained as a function of the azimuthal applied magnetic field within the effective-mass approximation. The double degeneracy of the non-zero electron's axial wave number (k z ) states is lifted by the current-induced magnetic field while that of the non-zero azimuthal quantum number (m) states is preserved. A further analysis is the evaluations of the oscillator strengths for optical transitions involving the lowest-order pair of the electron's energy subbands within the dipole approximation. The radiation field is taken as that of elliptically polarized light incident along the core axis. In this polarization and within the dipole approximation, the allowed transitions are only those governed by the following specific selection rules. The azimuthal quantum numbers of the initial and final states must differ by unity while the electron's axial wave number is conserved. The azimuthal magnetic field is also found to lift the multiple degeneracies of the k z ≠0 interaction integrals as well as those of the oscillator strengths for optical transitions

  8. On stationary states of electron beams in drift space

    International Nuclear Information System (INIS)

    Kovalev, N.F.

    2002-01-01

    The article is devoted to studying the conditions of formation and existence of virtual cathodes. The problem on stationary states of the strongly magnetized electron beams in the homogeneous drift channels is discussed. The problem on the planar and coaxial moduli of the drift spaces is considered. The possibility of existing the virtual cathodes in the coaxial tubular beams by the injection currents, smaller than the threshold ones is highly proved. The inaccuracy of results of a number of works, studying the properties of the virtual cathodes in the strongly magnetized electron beams, is shown [ru

  9. Surface study of liquid 3He using surface state electrons

    International Nuclear Information System (INIS)

    Shirahama, K.; Ito, S.; Suto, H.; Kono, K.

    1995-01-01

    We have measured the mobility of surface state electrons (SSE) on liquid 3 He, μ 3 , aiming to study the elementary surface excitations of the Fermi liquid. A gradual increase of μ 3 below 300 mK is attributed to the scattering of electrons by ripplons. Ripplons do exist in 3 He down to 100 mK. We observe an abrupt decrease of μ 3 , due to the transition to the Wigner solid (WS). The dependences of the WS conductivity and mobility on temperature and magnetic field differ from the SSE behavior on liquid 4 He

  10. Working memory training improves emotional states of healthy individuals

    Directory of Open Access Journals (Sweden)

    Hikaru eTakeuchi

    2014-10-01

    Full Text Available Working memory (WM capacity is associated with various emotional aspects, including states of depression and stress, reactions to emotional stimuli, and regulatory behaviors. We have previously investigated the effects of WM training (WMT on cognitive functions and brain structures. However, the effects of WMT on emotional states and related neural mechanisms among healthy young adults remain unknown. In the present study, we investigated these effects in young adults who underwent WMT or received no intervention for 4 weeks. Before and after the intervention, subjects completed self-report questionnaires related to their emotional states and underwent scanning sessions in which brain activities related to negative emotions were measured. Compared with controls, subjects who underwent WMT showed reduced anger, fatigue, and depression. Furthermore, WMT reduced activity in the left posterior insula during tasks evoking negative emotion, which was related to anger. It also reduced activity in the left frontoparietal area. These findings show that WMT can reduce negative mood and provide new insight into the clinical applications of WMT, at least among subjects with preclinical-level conditions.

  11. Evaluation of performance of electronic dosimeters for individual monitoring: tests in laboratory

    International Nuclear Information System (INIS)

    Garzon, W.J.; Khoury, H.J.; Barros, V.S.M. de; Medeiros, R.B.

    2015-01-01

    Electronic dosimeters based on direct ion storage technology are being widely used in many countries for individual monitoring in many applications of ionizing radiation. However, their use as routine dosimeter has been established in a few countries due to lack of accreditation or intercomparison programs. The objective of this study is to evaluate the performance of two direct íon storage dosimeters model available in the international market: the Miriom-Instadose-1 and RADOS DIS-1 to be eventually accepted for individual monitoring in Brazil. (author)

  12. Steady States in SIRS Epidemical Model of Mobile Individuals

    Institute of Scientific and Technical Information of China (English)

    ZHANG Duan-Ming; LIU Dan; HE Min-Hua; YU Xiao-Ling; PAN Gui-Jun; SUN Hong-Zhang; SU Xiang-Ying; SUN Fan; YIN Yan-Ping; LI Rui

    2006-01-01

    We consider an epidemical model within socially interacting mobile individuals to study the behaviors of steady statesof epidemic propagation in 2D networks. Using mean-field approximation and large scale simulations, we recover the usual epidemic behavior with critical thresholds δc and pc below which infectious disease dies out. For the population density δ far above δc, it is found that there is linear relationship between contact rate λ and the population density δ in the main. At the same time, the result obtained from mean-field approximation is compared with our numerical result, and it is found that these two results are similar by and large but not completely the same.

  13. Audit the effectiveness of the electronic system of public (state) procurement

    OpenAIRE

    Pysmenna, М.

    2017-01-01

    The study deals with the methodology of the audit the effectiveness of e-environment for public procurement. The purpose of this paper is deepening theoretical and methodological framework for auditing electronic systems for public (government) procurement. Research methods included analysis of legislation in the area of procurement, monitoring of individual transactions of public (state) procurement, interview with the responsible persons of budgetary funds on the assessment of the effective...

  14. Scanning electron microscopy of individual nanoparticle bio-markers in liquid

    Energy Technology Data Exchange (ETDEWEB)

    Liv, Nalan, E-mail: n.liv@tudelft.nl; Lazić, Ivan; Kruit, Pieter; Hoogenboom, Jacob P.

    2014-08-01

    We investigated SEM imaging of nanoparticle biomarkers suspended below a thin membrane, with the ultimate goal of integrating functional fluorescence and structural SEM measurements of samples kept at ambient or hydrated conditions. In particular, we investigated how resolving power in liquid SEM is affected by the interaction of the electron beam with the membrane. Simulations with the Geant4-based Monte Carlo scheme developed by Kieft and Bosch (2008) [1] are compared to experimental results with suspended nanoparticles. For 20 nm and 50 nm thin membranes, we found a beam broadening of 1.5 nm and 3 nm, respectively, with an excellent agreement between simulations and experiments. 15 nm Au nanoparticles and bio-functionalized core-shell quantum dots can be individually resolved in denser clusters. We demonstrated the imaging of single EGF-conjugated quantum dots docked at filopodia during cellular uptake with both fluorescence microscopy and SEM simultaneously. These results open novel opportunities for correlating live fluorescence microscopy with structural electron microscopy. - Highlights: • We investigate the achievable resolution in liquid scanning electron microscopy (SEM). • We demonstrate liquid SEM imaging of individual fluorescent nanoparticle bio-markers • We show imaging of cellular QDot uptake with simultaneous fluorescence microscopy and SEM. • The positions of individual QDots can be resolved with details on cellular structure.

  15. Scanning electron microscopy of individual nanoparticle bio-markers in liquid

    International Nuclear Information System (INIS)

    Liv, Nalan; Lazić, Ivan; Kruit, Pieter; Hoogenboom, Jacob P.

    2014-01-01

    We investigated SEM imaging of nanoparticle biomarkers suspended below a thin membrane, with the ultimate goal of integrating functional fluorescence and structural SEM measurements of samples kept at ambient or hydrated conditions. In particular, we investigated how resolving power in liquid SEM is affected by the interaction of the electron beam with the membrane. Simulations with the Geant4-based Monte Carlo scheme developed by Kieft and Bosch (2008) [1] are compared to experimental results with suspended nanoparticles. For 20 nm and 50 nm thin membranes, we found a beam broadening of 1.5 nm and 3 nm, respectively, with an excellent agreement between simulations and experiments. 15 nm Au nanoparticles and bio-functionalized core-shell quantum dots can be individually resolved in denser clusters. We demonstrated the imaging of single EGF-conjugated quantum dots docked at filopodia during cellular uptake with both fluorescence microscopy and SEM simultaneously. These results open novel opportunities for correlating live fluorescence microscopy with structural electron microscopy. - Highlights: • We investigate the achievable resolution in liquid scanning electron microscopy (SEM). • We demonstrate liquid SEM imaging of individual fluorescent nanoparticle bio-markers • We show imaging of cellular QDot uptake with simultaneous fluorescence microscopy and SEM. • The positions of individual QDots can be resolved with details on cellular structure

  16. Electron states and electron Raman scattering in semiconductor double cylindrical quantum well wire

    International Nuclear Information System (INIS)

    Munguía-Rodríguez, M; Riera, R; Betancourt-Riera, Ri; Betancourt-Riera, Re; Nieto Jalil, J M

    2016-01-01

    The differential cross section for an electron Raman scattering process in a semiconductor GaAs/AlGaAs double quantum well wire is calculated, and expressions for the electronic states are presented. The system is modeled by considering T = 0 K and also with a single parabolic conduction band, which is split into a subband system due to the confinement. The gain and differential cross-section for an electron Raman scattering process are obtained. In addition, the emission spectra for several scattering configurations are discussed, and interpretations of the singularities found in the spectra are given. The electron Raman scattering studied here can be used to provide direct information about the efficiency of the lasers. (paper)

  17. Application of the Raman technique to measure stress states in individual Si particles in a cast Al-Si alloy

    International Nuclear Information System (INIS)

    Harris, Stephen J.; O'Neill, Ann; Boileau, James; Donlon, William; Su, Xuming; Majumdar, B.S.

    2007-01-01

    While Raman spectroscopy is often used to measure stresses, the analyses are almost always limited to cases with simple stress states (uniaxial, equibiaxial). Recently we provided an experimental methodology to determine the full state of stress in Si wafers. Here we extend that methodology to interrogate stress states in Si particles embedded in an Al-Si alloy. Such determinations will ultimately be valuable for predicting ductility of cast Al, since a primary source of damage is cracking of eutectic Si particles. We combine electron back-scattered diffraction with the frequency shift, polarization and intensity of the Raman light to determine stress states. Stress states are measured both in the as-received residually stressed state and under in situ uniaxial loading. Comparison with finite element calculations shows good agreement. As an application of the technique, we show the determination of strength of an individual Si particle and compare the stress evolution with various models

  18. Electronic money in russia: current state and problems of development

    Directory of Open Access Journals (Sweden)

    T. G. Bondarenko

    2016-01-01

    Full Text Available Article is devoted to urgent problems of non-cash methods of calculation development by using electronic money – as one of the modern economically developed state strategic tasks. On modern economic science strong influence appears informatization process. The control expansion tendency, influence and distribution of commerce due to informatization of society led to emergence of the new phenomenon – information economy. Information economy brought new economic events which owing to their novelty are insufficiently studied to life. It is possible to carry electronic money to such phenomena of modern network economy Relevance and, in our opinion, timeliness of this scientific work, consisting in novelty of this non-cash payment method, its prospects and innovation within non-cash methods of calculations. Authors set as the purpose – studying of problems and the prospects of development of electronic money in the Russian Federation. In article theoretical bases of electronic money functioning are described. Determinations and classifications dismissed non-cash a method, and also the principles of electronic money functioning are considered, the questions of their historical development are raised.Authors analyzed statistical data on development of electronic services and channels of their using. Features, benefits and shortcomings of the current state of the market of electronic money are studied. The emphasis on that fact that in modern conditions considerable number of economic actors perform the activities, both in the real environment of economy, and within the virtual environment that promotes expansion of methods of their customer interaction by means of technical devices of personal computers, mobile phones is placed. In article common problems and tendencies of payments with using an electronic money are designated, the research on assessment of the current state and the prospects of electronic money

  19. Electronic and ground state properties of ThTe

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, Purvee, E-mail: purveebhardwaj@gmail.com; Singh, Sadhna, E-mail: drsadhna100@gmail.com [High Pressure Research Lab. Department of Physics Barkatullah University, Bhopal (MP) 462026 (India)

    2016-05-06

    The electronic properties of ThTe in cesium chloride (CsCl, B2) structure are investigated in the present paper. To study the ground state properties of thorium chalcogenide, the first principle calculations have been calculated. The bulk properties, including lattice constant, bulk modulus and its pressure derivative are obtained. The calculated equilibrium structural parameters are in good agreement with the available experimental and theoretical results.

  20. Electron structure of amorphous semi-conductor states

    International Nuclear Information System (INIS)

    Wiid, D.H.; Lemmer, R.H.

    1975-01-01

    The electrical properties of amorphous materials are determined by their electron states. Since the electrons are much lighter than the massive ions, the energy levels of the electrons are extremely sensitive to changes in the states of the ions, e.g. a change in their positions. A method has been developed to approximate the positional disorder inthe crystal by a compositional disorder, i.e. the substitution, in a pure crystal, of ions by impurities. The advantage of this lies in the retention of the periodicity of the lattice. This model is linked with an investigation at present under way, in which the mobility, electrical resistance, etc. of a silicon crystal is determined as a function of its amorphous state. It is for instance possible to control the degree of disorder in the crystal, and the problem is to characterise the disorder by a specific parameter. For theoretical calculations such a parameter is essential and it is therefore also the biggest shortcoming in all the theories that, as far as is known, have been developed. It is possible to set up a general phenomenological theory for, for example, electrical resistance, but in view of its complex nature only rough approximations can be made [af

  1. Engineering electronic states of periodic and quasiperiodic chains by buckling

    Science.gov (United States)

    Mukherjee, Amrita; Nandy, Atanu; Chakrabarti, Arunava

    2017-07-01

    The spectrum of spinless, non-interacting electrons on a linear chain that is buckled in a non-uniform, quasiperiodic manner is investigated within a tight binding formalism. We have addressed two specific cases, viz., a perfectly periodic chain wrinkled in a quasiperiodic Fibonacci pattern, and a quasiperiodic Fibonacci chain, where the buckling also takes place in a Fibonacci pattern. The buckling brings distant neighbors in the parent chain to close proximity, which is simulated by a tunnel hopping amplitude. It is seen that, in the perfectly ordered case, increasing the strength of the tunnel hopping (that is, bending the segments more) absolutely continuous density of states is retained towards the edges of the band, while the central portion becomes fragmented and host subbands of narrowing widths containing extended, current carrying states, and multiple isolated bound states formed as a result of the bending. A switching ;on; and ;off; of the electronic transmission can thus be engineered by buckling. On the other hand, in the second example of a quasiperiodic Fibonacci chain, imparting a quasiperiodic buckling is found to generate continuous subband(s) destroying the usual multifractality of the energy spectrum. We present exact results based on a real space renormalization group analysis, that is corroborated by explicit calculation of the two terminal electronic transport.

  2. Entanglement between electronic states in silicene and photons

    Energy Technology Data Exchange (ETDEWEB)

    Rastgoo, S. [Physics Department, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Shirkani, H. [Physics Department, Persian Gulf University, Bushehr 75169 (Iran, Islamic Republic of); Golshan, M.M., E-mail: golshan@susc.ac.ir [Physics Department, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of)

    2015-06-12

    Temporal behavior of entanglement between electrons in silicene and single mode radiations is reported. We show that the corresponding total Hamiltonian and time evolution operators are block diagonal. Initial states are divided into two categories for which buckling and the intrinsic spin–orbit effects are either of opposite or the same signs. Negativity shows that π-electrons and photons periodically become entangled for both categories. The entanglement spontaneously shows abrupt variations when buckling and the spin–orbit effects are equal but opposite in sign, leading to quantum phase transitions. As photonic excitations increase, the entanglement exhibits plateaus of constant durations for such initial states. - Highlights: • Time evolution of entanglement between π-electrons and photons in silicene is reported. • Intrinsic spin–orbit coupling (ISOC) and buckling effect (BE) are taken into account. • Initial states with ISOC and BE of opposite signs show quantum phase transitions. • Quantum phase transitions spontaneously occur when ISOC is equal to BE. • Periodic plateaus of maximal entanglement are observed for high photonic excitations.

  3. Electron-electron bound states in Maxwell-Chern-Simons-Proca QED3

    International Nuclear Information System (INIS)

    Belich, H.; Helayel-Neto, J.A.; Ferreira, M.M. Jr.; Maranhao Univ., Sao Luis, MA

    2002-10-01

    We start from a parity-breaking MCS QED 3 model with spontaneous breaking of the gauge symmetry as a framework for evaluation of the electron-electron interaction potential and for attainment of numerical values for the e - e - - bound state. Three expressions V eff↓↓ , V eff↓↑ , V eff↓↓ ) are obtained according to the polarization state of the scattered electrons. In an energy scale compatible with condensed matter electronic excitations, these potentials become degenerated. The resulting potential is implemented in the Schroedinger equation and the variational method is applied to carry out the electronic binding energy. The resulting binding energies in the scale of 10-100 meV and a correlation length in the scale of 10 - 30 Angstrom are possible indications that the MCS-QED 3 model adopted may be suitable to address an eventual case of e - e - pairing in the presence of parity-symmetry breakdown. The data analyzed here suggest an energy scale of 10-100 meV to fix the breaking of the U(1)-symmetry. (author)

  4. Integral elastic, electronic-state, ionization, and total cross sections for electron scattering with furfural

    Science.gov (United States)

    Jones, D. B.; da Costa, R. F.; Varella, M. T. do N.; Bettega, M. H. F.; Lima, M. A. P.; Blanco, F.; García, G.; Brunger, M. J.

    2016-04-01

    We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20-250 eV. Wherever possible, those results are compared to corresponding excitation cross sections in the structurally similar species furan, as previously reported by da Costa et al. [Phys. Rev. A 85, 062706 (2012)] and Regeta and Allan [Phys. Rev. A 91, 012707 (2015)]. Generally, very good agreement is found. In addition, ICSs calculated with our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section for electron-furfural scattering. Where possible, those calculated IAM-SCAR+I ICS results are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, but only for the band I and band II excited electronic states, we also present results from our Schwinger multichannel method with pseudopotentials calculations. Those results are found to be in good qualitative accord with the present experimental ICSs. Finally, with a view to assembling a complete cross section data base for furfural, some binary-encounter-Bethe-level total ionization cross sections for this collision system are presented.

  5. Electron-electron bound states in Maxwell-Chern-Simons-Proca QED{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Helayel-Neto, J.A. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil)]|[Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas]. E-mail: belich@cbpf.br; helayel@gft.ucp.br; Del Cima, O.M. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil)]. E-mail: delcima@gft.ucp.br; Ferreira, M.M. Jr. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil)]|[Maranhao Univ., Sao Luis, MA (Brazil). Dept. de Fisica]. E-mail: manojr@cbpf.br

    2002-10-01

    We start from a parity-breaking MCS QED{sub 3} model with spontaneous breaking of the gauge symmetry as a framework for evaluation of the electron-electron interaction potential and for attainment of numerical values for the e{sup -}e{sup -} - bound state. Three expressions (V{sub eff{down_arrow}}{sub {down_arrow}}, V{sub eff{down_arrow}}{sub {up_arrow}}, V{sub eff{down_arrow}}{sub {down_arrow}}) are obtained according to the polarization state of the scattered electrons. In an energy scale compatible with condensed matter electronic excitations, these potentials become degenerated. The resulting potential is implemented in the Schroedinger equation and the variational method is applied to carry out the electronic binding energy. The resulting binding energies in the scale of 10-100 meV and a correlation length in the scale of 10 - 30 Angstrom are possible indications that the MCS-QED{sub 3} model adopted may be suitable to address an eventual case of e{sup -}e{sup -} pairing in the presence of parity-symmetry breakdown. The data analyzed here suggest an energy scale of 10-100 meV to fix the breaking of the U(1)-symmetry. (author)

  6. The electronic density of states of disordered compounds

    International Nuclear Information System (INIS)

    Geertsma, W.; Dijkstra, J.

    1984-11-01

    Recently, the electronic properties of liquid alkali (Li, Na, K, Rb, Cs)-group IV (Si, Ge, Sn, Pb) alloys have been discussed by the present authors using a tight-binding model. Only anion orbitals (= group IV) are taken into account. Disorder is described by a pseudo lattice, which takes into account local coordination in one of the sublattices (cation or anion) only. In the first part of this paper it is shown that this approximation is consistent with the usual valence rules used by structural chemists for crystalline structures. In the second part of the paper the solutions for the density of states of the tight-binding Hamiltonian are studied for a number of pseudolattices. The infinite set of Green function equations is solved by using the effective transfer method, which replaces the famous Block condition. It is shown that such a model can explain the formation of bandgaps in disordered systems. By choosing the proper smallest cluster(s) of transfer loops to model the real structure by a pseudolattice, a density of states is obtained which represents properly that of the corresponding crystalline structure. Structures reminiscent to those caused by van Hove singularities already appear in the electronic density of states when relatively small cluster(s) of transfer loops are used. The approach outlined in this paper is capable of describing the electronic density of states due to various degrees of local order in a sublattice. Some of the peculiarities occurring in the solution of the density of states of certain pseudolattices, such as poles outside the band, are discussed in an appendix. (author)

  7. Electron-electron bound states in parity-preserving QED3

    International Nuclear Information System (INIS)

    Belich, H.; Helayel-Neto, J.A.; Centro Brasileiro de Pesquisas Fisicas; Cima, O.M. del; Ferreira Junior, M.M.; Maranhao Univ., Sao Luis, MA

    2002-04-01

    By considering the Higgs mechanism in the framework of a parity-preserving Planar Quantum Electrodynamics, one shows that an attractive electron-electron interaction may dominate. The e - e - interaction potential emerges as the non-relativistic limit of the Moeller scattering amplitude and it results attractive with a suitable choice of parameters. Numerically values of the e - e - binding energy are obtained by solving the two-dimensional Schroedinger equation. The existence of bound states is a strong indicative that this model may be adopted to address the pairing mechanism of high-T c superconductivity. (author)

  8. Electron-electron bound states in parity-preserving QED{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Helayel-Neto, J.A. [Universidade Catolica do Petropolis, RJ (Brazil). Grupo de Fisica Teorica]|[Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas; Cima, O.M. del [Universidade Catolica do Petropolis, RJ (Brazil). Grupo de Fisica Teorica; Ferreira Junior, M.M. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas]|[Maranhao Univ., Sao Luis, MA (Brazil). Dept. de Fisica

    2002-04-01

    By considering the Higgs mechanism in the framework of a parity-preserving Planar Quantum Electrodynamics, one shows that an attractive electron-electron interaction may dominate. The e{sup -}e{sup -} interaction potential emerges as the non-relativistic limit of the Moeller scattering amplitude and it results attractive with a suitable choice of parameters. Numerically values of the e{sup -}e{sup -} binding energy are obtained by solving the two-dimensional Schroedinger equation. The existence of bound states is a strong indicative that this model may be adopted to address the pairing mechanism of high-T{sub c} superconductivity. (author)

  9. Single electron probes of fractional quantum hall states

    Science.gov (United States)

    Venkatachalam, Vivek

    When electrons are confined to a two dimensional layer with a perpendicular applied magnetic field, such that the ratio of electrons to flux quanta (nu) is a small integer or simple rational value, these electrons condense into remarkable new phases of matter that are strikingly different from the metallic electron gas that exists in the absence of a magnetic field. These phases, called integer or fractional quantum Hall (IQH or FQH) states, appear to be conventional insulators in their bulk, but behave as a dissipationless metal along their edge. Furthermore, electrical measurements of such a system are largely insensitive to the detailed geometry of how the system is contacted or even how large the system is... only the order in which contacts are made appears to matter. This insensitivity to local geometry has since appeared in a number of other two and three dimensional systems, earning them the classification of "topological insulators" and prompting an enormous experimental and theoretical effort to understand their properties and perhaps manipulate these properties to create robust quantum information processors. The focus of this thesis will be two experiments designed to elucidate remarkable properties of the metallic edge and insulating bulk of certain FQH systems. To study such systems, we can use mesoscopic devices known as single electron transistors (SETs). These devices operate by watching single electrons hop into and out of a confining box and into a nearby wire (for measurement). If it is initially unfavorable for an electron to leave the box, it can be made favorable by bringing another charge nearby, modifying the energy of the confined electron and pushing it out of the box and into the nearby wire. In this way, the SET can measure nearby charges. Alternatively, we can heat up the nearby wire to make it easier for electrons to enter and leave the box. In this way, the SET is a sensitive thermometer. First, by operating the SET as an

  10. Electron impact excitation of xenon from the metastable state to the excited states

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Jun; Dong Chenzhong; Xie Luyou; Zhou Xiaoxin [College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Jianguo [Institute of Applied Physics and Computational Mathematic, Beijing 100088 (China)], E-mail: dongcz@nwnu.edu.cn

    2008-12-28

    The electron impact excitation cross sections from the lowest metastable state 5p{sup 5}6sJ = 2 to the six lowest excited states of the 5p{sup 5}6p configuration of xenon are calculated systematically by using the fully relativistic distorted wave method. In order to discuss the effects of target state descriptions on the electron impact excitation cross sections, two correlation models are used to describe the target states based on the multiconfiguration Dirac-Fock (MCDF) method. It is found that the correlation effects play a very important role in low energy impact. For high energy impact, however, the cross sections are not sensitive to the description of the target states, but many more partial waves must be included.

  11. Electron capture into excited states of multi-charged ions

    International Nuclear Information System (INIS)

    Dijkkamp, D.

    1985-01-01

    This thesis deals with charge exchange reactions in slow collisions of multi-charged ions with neutral atoms or molecules. These reactions proceed very efficiently via a curve crossing mechanism, which leads to preferential population of excited states of the ion. The subsequent decay of these states leads to the emission of characteristic radiation. From wavelength resolved measurements of the absolute intensity of this radiation, cross sections for selective population of the excited (n,l-) states of the ion were determined. In addition, for some systems the total capture cross section was measured directly by means of charge state analysis of the secondary projectile ions. The role of charge exchange processes in fusion plasmas and in astrophysical plasmas is indicated. An experimental set-up is described with emphasis on the Electron Cyclotron Resonance Ion Source that was used in the experiments. Results for collisions of C 6+ , N 6+ , O 6+ and Ne 6+ with He, H 2 and Ar are presented as well as for electron capture from Li atoms by C 4+ and He 2+ . The interaction of the iso-electronic sequence C 4+ , N 5+ , O 6+ with atomic hydrogen, molecular hydrogen and helium is studied. First results for partial and total cross sections in collisions of fully stripped carbon, nitrogen and oxygen ions with atomic hydrogen are presented. These data are of particular importance for applications in fusion diagnostics. The data indicate that calculations of both molecular and atomic orbital type yield correct results, if an extended basis set is used. (Auth.)

  12. Benzonitrile: Electron affinity, excited states, and anion solvation

    Science.gov (United States)

    Dixon, Andrew R.; Khuseynov, Dmitry; Sanov, Andrei

    2015-10-01

    We report a negative-ion photoelectron imaging study of benzonitrile and several of its hydrated, oxygenated, and homo-molecularly solvated cluster anions. The photodetachment from the unsolvated benzonitrile anion to the X ˜ 1 A 1 state of the neutral peaks at 58 ± 5 meV. This value is assigned as the vertical detachment energy (VDE) of the valence anion and the upper bound of adiabatic electron affinity (EA) of benzonitrile. The EA of the lowest excited electronic state of benzonitrile, a ˜ 3 A 1 , is determined as 3.41 ± 0.01 eV, corresponding to a 3.35 eV lower bound for the singlet-triplet splitting. The next excited state, the open-shell singlet A ˜ 1 A 1 , is found about an electron-volt above the triplet, with a VDE of 4.45 ± 0.01 eV. These results are in good agreement with ab initio calculations for neutral benzonitrile and its valence anion but do not preclude the existence of a dipole-bound state of similar energy and geometry. The step-wise and cumulative solvation energies of benzonitrile anions by several types of species were determined, including homo-molecular solvation by benzonitrile, hydration by 1-3 waters, oxygenation by 1-3 oxygen molecules, and mixed solvation by various combinations of O2, H2O, and benzonitrile. The plausible structures of the dimer anion of benzonitrile were examined using density functional theory and compared to the experimental observations. It is predicted that the dimer anion favors a stacked geometry capitalizing on the π-π interactions between the two partially charged benzonitrile moieties.

  13. Electronic structures of interfacial states formed at polymeric semiconductor heterojunctions

    Science.gov (United States)

    Huang, Ya-Shih; Westenhoff, Sebastian; Avilov, Igor; Sreearunothai, Paiboon; Hodgkiss, Justin M.; Deleener, Caroline; Friend, Richard H.; Beljonne, David

    2008-06-01

    Heterojunctions between organic semiconductors are central to the operation of light-emitting and photovoltaic diodes, providing respectively for electron-hole capture and separation. However, relatively little is known about the character of electronic excitations stable at the heterojunction. We have developed molecular models to study such interfacial excited electronic excitations that form at the heterojunction between model polymer donor and polymer acceptor systems: poly(9,9-dioctylfluorene-co-bis-N,N-(4-butylphenyl)-bis-N,N-phenyl-1,4-phenylenediamine) (PFB) with poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT), and poly(9,9-dioctylfluorene-co-N-(4-butylphenyl)diphenylamine) (TFB) with F8BT. We find that for stable ground-state geometries the excited state has a strong charge-transfer character. Furthermore, when partly covalent, modelled radiative lifetimes (~10-7s) and off-chain axis polarization (30∘) match observed `exciplex' emission. Additionally for the PFB:F8BT blend, geometries with fully ionic character are also found, thus accounting for the low electroluminescence efficiency of this system.

  14. Electronic excited states and relaxation dynamics in polymer heterojunction systems

    Science.gov (United States)

    Ramon, John Glenn Santos

    , we examine the effect of the nanoscale interfacial morphology and solvation on the electronic excited states of TFB/F8BT. Here, we employ time-dependent density functional theory (TD-DFT) to investigate the relevant excited states of two stacking configurations. We show that the calculated states agree with the excited states responsible for the experimentally observed emission peaks and that these states are blue shifted relative to those of the isolated chain. Furthermore, slight lateral shifts in the stacking orientation not only shift the excited state energies; more importantly, they alter the nature of these states altogether. Lastly, we see that solvation greatly stabilizes the charge-transfer states.

  15. Electron scattering from the ground state of mercury

    International Nuclear Information System (INIS)

    Fursa, D.; Bray, I.

    2000-01-01

    Full text: Close-coupling calculations have been performed for electron scattering from the ground state of mercury. We have used non-relativistic convergent close-coupling computer code with only minor modifications in order to account for the most prominent relativistic effects. These are the relativistic shift effect and singlet-triplet mixing. Very good agreement with measurements of differential cross sections for elastic scattering and excitation of 6s6p 1 P state at all energies is obtained. It is well recognised that a consistent approach to electron scattering from heavy atoms (like mercury, with nuclear charge Z=80) must be based on a fully relativistic Dirac equations based technique. While development of such technique is under progress in our group, the complexity of the problem ensures that results will not be available in the near future. On other hand, there is considerable interest in reliable theoretical results for electron scattering from heavy atoms from both applications and the need to interpret existing experimental data. This is particularly the case for mercury, which is the major component in fluorescent lighting devices and has been the subject of intense experimental study since nineteen thirties. Similarly to our approach for alkaline-earth atoms we use a model of two valence electrons above an inert Hartree-Fock core to describe the mercury atom. Note that this model does not account for any core excited states which are present in the mercury discrete spectrum. The major effect of missing core-excited states is substantial underestimation of the static dipole polarizability of the mercury ground state (34 a.u.) and consequent underestimation of the forward scattering elastic cross sections. We correct for this by adding in the scattering calculations a phenomenological polarization potential. In order to obtain correct ground state ionization energy for mercury one has to account for the relativistic shift effect. We model this

  16. Integral elastic, electronic-state, ionization, and total cross sections for electron scattering with furfural

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Costa, R. F. da [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, Campinas, 13083-859 São Paulo (Brazil); Departamento de Física, Universidade Federal do Espírito Santo, 29075-910, Vitória, Espírito Santo (Brazil); Varella, M. T. do N. [Instituto de Física, Universidade de São Paulo, CP 66318, 05315-970 São Paulo (Brazil); Bettega, M. H. F. [Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-990 Curitiba, Paraná (Brazil); Lima, M. A. P. [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, Campinas, 13083-859 São Paulo (Brazil); Blanco, F. [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid E-28040 (Spain); García, G. [Instituto de Física Fundamental, CSIC, Serrano 113-bis, 28006 Madrid (Spain); Brunger, M. J., E-mail: Michael.Brunger@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2016-04-14

    We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20–250 eV. Wherever possible, those results are compared to corresponding excitation cross sections in the structurally similar species furan, as previously reported by da Costa et al. [Phys. Rev. A 85, 062706 (2012)] and Regeta and Allan [Phys. Rev. A 91, 012707 (2015)]. Generally, very good agreement is found. In addition, ICSs calculated with our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section for electron–furfural scattering. Where possible, those calculated IAM-SCAR+I ICS results are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, but only for the band I and band II excited electronic states, we also present results from our Schwinger multichannel method with pseudopotentials calculations. Those results are found to be in good qualitative accord with the present experimental ICSs. Finally, with a view to assembling a complete cross section data base for furfural, some binary-encounter-Bethe-level total ionization cross sections for this collision system are presented.

  17. Integral elastic, electronic-state, ionization, and total cross sections for electron scattering with furfural

    International Nuclear Information System (INIS)

    Jones, D. B.; Costa, R. F. da; Varella, M. T. do N.; Bettega, M. H. F.; Lima, M. A. P.; Blanco, F.; García, G.; Brunger, M. J.

    2016-01-01

    We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20–250 eV. Wherever possible, those results are compared to corresponding excitation cross sections in the structurally similar species furan, as previously reported by da Costa et al. [Phys. Rev. A 85, 062706 (2012)] and Regeta and Allan [Phys. Rev. A 91, 012707 (2015)]. Generally, very good agreement is found. In addition, ICSs calculated with our independent atom model (IAM) with screening corrected additivity rule (SCAR) formalism, extended to account for interference (I) terms that arise due to the multi-centre nature of the scattering problem, are also reported. The sum of those ICSs gives the IAM-SCAR+I total cross section for electron–furfural scattering. Where possible, those calculated IAM-SCAR+I ICS results are compared against corresponding results from the present measurements with an acceptable level of accord being obtained. Similarly, but only for the band I and band II excited electronic states, we also present results from our Schwinger multichannel method with pseudopotentials calculations. Those results are found to be in good qualitative accord with the present experimental ICSs. Finally, with a view to assembling a complete cross section data base for furfural, some binary-encounter-Bethe-level total ionization cross sections for this collision system are presented.

  18. Electron-phonon interactions and intrinsic nonadiabatic state of superconductors

    International Nuclear Information System (INIS)

    Banacky, Pavol

    2007-01-01

    Study of band structure of YBa 2 Cu 3 O 7 has shown that electron coupling to A g , B 2g and B 3g modes results in fluctuation of saddle point of one of the CuO plane d-pσ band in Y point of 1st BZ across Fermi level. It represents breakdown of adiabatic Born-Oppenheimer approximation and transition of the system into intrinsic nonadiabatic state, ω > E F . Results show that system is stabilized in this state at distorted nuclear geometry. Stabilization effect is mainly due to strong dependence of the electronic motion on instantaneous nuclear momenta. On the lattice scale, the intrinsic nonadiabatic state is geometrically degenerate at broken translation symmetry - system has fluxional nuclear configuration of O2, O3 atoms in CuO planes. It enables formation of mobile bipolarons that can move in the lattice without dissipation. Described effects are absent in non-superconducting YBa 2 Cu 3 O 6

  19. Electron phonon interactions and intrinsic nonadiabatic state of superconductors

    Science.gov (United States)

    Baňacký, Pavol

    2007-09-01

    Study of band structure of YBa 2Cu 3O 7 has shown that electron coupling to A g, B 2g and B 3g modes results in fluctuation of saddle point of one of the CuO plane d-pσ band in Y point of 1st BZ across Fermi level. It represents breakdown of adiabatic Born-Oppenheimer approximation and transition of the system into intrinsic nonadiabatic state, ω > EF. Results show that system is stabilized in this state at distorted nuclear geometry. Stabilization effect is mainly due to strong dependence of the electronic motion on instantaneous nuclear momenta. On the lattice scale, the intrinsic nonadiabatic state is geometrically degenerate at broken translation symmetry - system has fluxional nuclear configuration of O2, O3 atoms in CuO planes. It enables formation of mobile bipolarons that can move in the lattice without dissipation. Described effects are absent in non-superconducting YBa 2Cu 3O 6.

  20. The New Czech State Citizenship Act: the Further Liberalization of Individual Rights or the Enpowerment of State Authority?

    Czech Academy of Sciences Publication Activity Database

    Emmert, František

    2014-01-01

    Roč. 5, č. 1 (2014), s. 187-193 ISSN 2042-6402 Institutional support: RVO:68378122 Keywords : State Citizenship Act; * ius sanguinis * individual rights * Czech citizens Subject RIV: AG - Legal Sciences

  1. Using Electronic Health Record Data to Measure Care Quality for Individuals with Multiple Chronic Medical Conditions.

    Science.gov (United States)

    Bayliss, Elizabeth A; McQuillan, Deanna B; Ellis, Jennifer L; Maciejewski, Matthew L; Zeng, Chan; Barton, Mary B; Boyd, Cynthia M; Fortin, Martin; Ling, Shari M; Tai-Seale, Ming; Ralston, James D; Ritchie, Christine S; Zulman, Donna M

    2016-09-01

    To inform the development of a data-driven measure of quality care for individuals with multiple chronic conditions (MCCs) derived from an electronic health record (EHR). Qualitative study using focus groups, interactive webinars, and a modified Delphi process. Research department within an integrated delivery system. The webinars and Delphi process included 17 experts in clinical geriatrics and primary care, health policy, quality assessment, health technology, and health system operations. The focus group included 10 individuals aged 70-87 with three to six chronic conditions selected from a random sample of individuals aged 65 and older with three or more chronic medical conditions. Through webinars and the focus group, input was solicited on constructs representing high-quality care for individuals with MCCs. A working list was created of potential measures representing these constructs. Using a modified Delphi process, experts rated the importance of each possible measure and the feasibility of implementing each measure using EHR data. High-priority constructs reflected processes rather than outcomes of care. High-priority constructs that were potentially feasible to measure included assessing physical function, depression screening, medication reconciliation, annual influenza vaccination, outreach after hospital admission, and documented advance directives. High-priority constructs that were less feasible to measure included goal setting and shared decision-making, identifying drug-drug interactions, assessing social support, timely communication with patients, and other aspects of good customer service. Lower-priority domains included pain assessment, continuity of care, and overuse of screening or laboratory testing. High-quality MCC care should be measured using meaningful process measures rather than outcomes. Although some care processes are currently extractable from electronic data, capturing others will require adapting and applying technology to

  2. Solid state lasers: a major direction in quantum electronics

    International Nuclear Information System (INIS)

    Shcherbakov, I.A.

    2004-01-01

    The aim of the report is to analyze development of solid-state lasers (SSL) as one of the most important avenues of the quantum electronics. The obtained intensity of a laser radiation at the focus equal to 5x10 1 0 W/cm 2 (the field intensity equal to about 5x10 1 0 V/cm 2 ) is noted to enable to observe nonlinear quantum- electrodynamic effects. Besides, one managed to increase the SSL efficiency conventionally equal to maximum 3% up to 48-50%. Paper describes new types of SSLs, namely, the crystalline fiber lasers with the lateral gradient of the index of refraction [ru

  3. Parallelization for first principles electronic state calculation program

    International Nuclear Information System (INIS)

    Watanabe, Hiroshi; Oguchi, Tamio.

    1997-03-01

    In this report we study the parallelization for First principles electronic state calculation program. The target machines are NEC SX-4 for shared memory type parallelization and FUJITSU VPP300 for distributed memory type parallelization. The features of each parallel machine are surveyed, and the parallelization methods suitable for each are proposed. It is shown that 1.60 times acceleration is achieved with 2 CPU parallelization by SX-4 and 4.97 times acceleration is achieved with 12 PE parallelization by VPP 300. (author)

  4. Modeling the high-energy electronic state manifold of adenine: Calibration for nonlinear electronic spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nenov, Artur, E-mail: Artur.Nenov@unibo.it; Giussani, Angelo; Segarra-Martí, Javier; Jaiswal, Vishal K. [Dipartimento di Chimica “G. Ciamician,” Università di Bologna, Via Selmi 2, IT-40126 Bologna (Italy); Rivalta, Ivan [Université de Lyon, CNRS, Institut de Chimie de Lyon, École Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07 (France); Cerullo, Giulio [Dipartimento di Fisica, Politecnico di Milano, IFN-CNR, Piazza Leonardo Da Vinci 32, IT-20133 Milano (Italy); Mukamel, Shaul [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States); Garavelli, Marco, E-mail: marco.garavelli@unibo.it, E-mail: marco.garavelli@ens-lyon.fr [Dipartimento di Chimica “G. Ciamician,” Università di Bologna, Via Selmi 2, IT-40126 Bologna (Italy); Université de Lyon, CNRS, Institut de Chimie de Lyon, École Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07 (France)

    2015-06-07

    Pump-probe electronic spectroscopy using femtosecond laser pulses has evolved into a standard tool for tracking ultrafast excited state dynamics. Its two-dimensional (2D) counterpart is becoming an increasingly available and promising technique for resolving many of the limitations of pump-probe caused by spectral congestion. The ability to simulate pump-probe and 2D spectra from ab initio computations would allow one to link mechanistic observables like molecular motions and the making/breaking of chemical bonds to experimental observables like excited state lifetimes and quantum yields. From a theoretical standpoint, the characterization of the electronic transitions in the visible (Vis)/ultraviolet (UV), which are excited via the interaction of a molecular system with the incoming pump/probe pulses, translates into the determination of a computationally challenging number of excited states (going over 100) even for small/medium sized systems. A protocol is therefore required to evaluate the fluctuations of spectral properties like transition energies and dipole moments as a function of the computational parameters and to estimate the effect of these fluctuations on the transient spectral appearance. In the present contribution such a protocol is presented within the framework of complete and restricted active space self-consistent field theory and its second-order perturbation theory extensions. The electronic excited states of adenine have been carefully characterized through a previously presented computational recipe [Nenov et al., Comput. Theor. Chem. 1040–1041, 295-303 (2014)]. A wise reduction of the level of theory has then been performed in order to obtain a computationally less demanding approach that is still able to reproduce the characteristic features of the reference data. Foreseeing the potentiality of 2D electronic spectroscopy to track polynucleotide ground and excited state dynamics, and in particular its expected ability to provide

  5. State-level public policy as a predictor of individual and family well-being.

    Science.gov (United States)

    Zimmerman, S L

    1987-01-01

    This exploratory study examines the relationship between state-level public policy and individual and family well-being and factors that affect it. The inquiry, based on exchange and choice theories, assumes that state-level public policy reflects states' awareness of the needs of individuals and families, their ability to predict the future in failing to meet them, and the extent to which the norm of reciprocity prevails in the 50 states. Measures of states' collective choices were states' per capita expenditures for public welfare, education, and health, and per capita taxes in 1980; measures of states' individual and well- or ill-being, or social malaise, were states' teenage birthrates, infant death rates, and suicide rates. Taken into account as antecedent and intervening variables were age, gender, and racial composition, income distribution, marital, socioeconomic, and employment status of states' populations, and attitudes toward public spending. The findings show that higher state expenditures for public welfare and for education indeed contribute to individual and family well-being as measured by lower state rates of suicide and teenage births. States per capita spending for education, which together with state per capita spending for public welfare was a positive predictor of school completion rates and positively associated with states' income level, accounted for almost all of the variance in states' per capita taxes. State spending for public welfare was not a predictor of state per capita taxes. These findings are cause for considerable concern given the reduced role of the federal government in human affairs, particularly in states whose choices violate the assumptions underlying exchange and choice theories and the norm of reciprocity which says that people should help, not hurt, others.

  6. Bound states in strongly correlated magnetic and electronic systems

    International Nuclear Information System (INIS)

    Trebst, S.

    2002-02-01

    A novel strong coupling expansion method to calculate two-particle spectra of quantum lattice models is developed. The technique can be used to study bosonic and fermionic models and in principle it can be applied to systems in any dimension. A number of strongly correlated magnetic and electronic systems are examined including the two-leg spin-half Heisenberg ladder, the dimerized Heisenberg chain with a frustrating next-nearest neighbor interaction, coupled Heisenberg ladders, and the one-dimensional Kondo lattice model. In the various models distinct bound states are found below the two-particle continuum. Quantitative calculations of the dispersion, coherence length and binding energy of these bound states are used to describe spectroscopic experiments on (Ca,La) 14 Cu 24 O 41 and NaV 2 O 5 . (orig.)

  7. Revealing energy level structure of individual quantum dots by tunneling rate measured by single-electron sensitive electrostatic force spectroscopy.

    Science.gov (United States)

    Roy-Gobeil, Antoine; Miyahara, Yoichi; Grutter, Peter

    2015-04-08

    We present theoretical and experimental studies of the effect of the density of states of a quantum dot (QD) on the rate of single-electron tunneling that can be directly measured by electrostatic force microscopy (e-EFM) experiments. In e-EFM, the motion of a biased atomic force microscope cantilever tip modulates the charge state of a QD in the Coulomb blockade regime. The charge dynamics of the dot, which is detected through its back-action on the capacitavely coupled cantilever, depends on the tunneling rate of the QD to a back-electrode. The density of states of the QD can therefore be measured through its effect on the energy dependence of tunneling rate. We present experimental data on individual 5 nm colloidal gold nanoparticles that exhibit a near continuous density of state at 77 K. In contrast, our analysis of already published data on self-assembled InAs QDs at 4 K clearly reveals discrete degenerate energy levels.

  8. Electron paramagnetic resonance detection of carotenoid triplet states

    International Nuclear Information System (INIS)

    Frank, H.A.; Bolt, J.D.; deCosta, S.M.; Sauer, K.

    1980-01-01

    Triplet states of carotenoids have been detected by X-band electron paramagnetic resonance (EPR) and are reported here for the first time. The systems in which carotenoid triplets are observed include cells of photosynthetic bacteria, isolated bacteriochlorophyll-protein complexes, and detergent micelles which contain β-carotene. It is well known that if electron transfer is blocked following the initial acceptor in the bacterial photochemical reaction center, back reaction of the primary radical pair produces a bacteriochlorophyll dimer triplet. Previous optical studies have shown that in reaction centers containing carotenoids the bacteriochlorophyll dimer triplet sensitizes the carotenoid triplet. We have observed this carotenoid triplet state by EPR in reaction centers of Rhodopseudomonas sphaeroides, strain 2.4.1 (wild type), which contain the carotenoid spheroidene. The zero-field splitting parameters of the triplet spectrum are /D/ = 0.0290 +- 0.0005 cm -1 and /E/ = 0.0044 +-0.0006 cm -1 , in contrast with the parameters of the bacteriochlorophyll dimer triplet, which are /D/ = 0.0189 +- 0.0004 cm -1 and /E/ = 0.0032 +- 0.004 cm -1 . Bacteriochlorophyll in a light harvesting protein complex from Rps. sphaeroides, wild type, also sensitizes carotenoid triplet formation. In whole cells the EPR spectra vary with temperature between 100 and 10 K. Carotenoid triplets also have been observed by EPR in whole cells of Rps. sphaeroides and cells of Rhodospirillum rubrum which contain the carotenoid spirilloxanthin. Attempts to observe the triplet state EPR spectrum of β-carotene in numerous organic solvents failed. However, in nonionic detergent micelles and in phospholipid bilayer vesicles β-carotene gives a triplet state spectrum with /D/ = 0.0333 +- 0.0010 cm -1 and /E/ = 0.0037 +- 0.0010 cm -1 . 6 figures, 1 table

  9. Electron-impact excitation and ionization cross sections for ground state and excited helium atoms

    International Nuclear Information System (INIS)

    Ralchenko, Yu.; Janev, R.K.; Kato, T.; Fursa, D.V.; Bray, I.; Heer, F.J. de

    2008-01-01

    Comprehensive and critically assessed cross sections for the electron-impact excitation and ionization of ground state and excited helium atoms are presented. All states (atomic terms) with n≤4 are treated individually, while the states with n≥5 are considered degenerate. For the processes involving transitions to and from n≥5 levels, suitable cross section scaling relations are presented. For a large number of transitions, from both ground and excited states, convergent close coupling calculations were performed to achieve a high accuracy of the data. The evaluated/recommended cross section data are presented by analytic fit functions, which preserve the correct asymptotic behavior of the cross sections. The cross sections are also displayed in graphical form

  10. Joint estimation over multiple individuals improves behavioural state inference from animal movement data.

    Science.gov (United States)

    Jonsen, Ian

    2016-02-08

    State-space models provide a powerful way to scale up inference of movement behaviours from individuals to populations when the inference is made across multiple individuals. Here, I show how a joint estimation approach that assumes individuals share identical movement parameters can lead to improved inference of behavioural states associated with different movement processes. I use simulated movement paths with known behavioural states to compare estimation error between nonhierarchical and joint estimation formulations of an otherwise identical state-space model. Behavioural state estimation error was strongly affected by the degree of similarity between movement patterns characterising the behavioural states, with less error when movements were strongly dissimilar between states. The joint estimation model improved behavioural state estimation relative to the nonhierarchical model for simulated data with heavy-tailed Argos location errors. When applied to Argos telemetry datasets from 10 Weddell seals, the nonhierarchical model estimated highly uncertain behavioural state switching probabilities for most individuals whereas the joint estimation model yielded substantially less uncertainty. The joint estimation model better resolved the behavioural state sequences across all seals. Hierarchical or joint estimation models should be the preferred choice for estimating behavioural states from animal movement data, especially when location data are error-prone.

  11. Selective coupling of individual electron and nuclear spins with integrated all-spin coherence protection

    Science.gov (United States)

    Terletska, Hanna; Dobrovitski, Viatcheslav

    2015-03-01

    The electron spin of the NV center in diamond is a promising platform for spin sensing. Applying the dynamical decoupling, the NV electron spin can be used to detect the individual weakly coupled carbon-13 nuclear spins in diamond and employ them for small-scale quantum information processing. However, the nuclear spins within this approach remain unprotected from decoherence, which ultimately limits the detection and restricts the fidelity of the quantum operation. Here we investigate possible schemes for combining the resonant decoupling on the NV spin with the decoherence protection of the nuclear spins. Considering several schemes based on pulse and continuous-wave decoupling, we study how the joint electron-nuclear spin dynamics is affected. We identify regimes where the all-spin coherence protection improves the detection and manipulation. We also discuss potential applications of the all-spin decoupling for detecting spins outside diamond, with the purpose of implementing the nanoscale NMR. This work was supported by the US Department of Energy Basic Energy Sciences (Contract No. DE-AC02-07CH11358).

  12. Two dimensional electron systems for solid state quantum computation

    Science.gov (United States)

    Mondal, Sumit

    Two dimensional electron systems based on GaAs/AlGaAs heterostructures are extremely useful in various scientific investigations of recent times including the search for quantum computational schemes. Although significant strides have been made over the past few years to realize solid state qubits on GaAs/AlGaAs 2DEGs, there are numerous factors limiting the progress. We attempt to identify factors that have material and design-specific origin and develop ways to overcome them. The thesis is divided in two broad segments. In the first segment we describe the realization of a new field-effect induced two dimensional electron system on GaAs/AlGaAs heterostructure where the novel device-design is expected to suppress the level of charge noise present in the device. Modulation-doped GaAs/AlGaAs heterostructures are utilized extensively in the study of quantum transport in nanostructures, but charge fluctuations associated with remote ionized dopants often produce deleterious effects. Electric field-induced carrier systems offer an attractive alternative if certain challenges can be overcome. We demonstrate a field-effect transistor in which the active channel is locally devoid of modulation-doping, but silicon dopant atoms are retained in the ohmic contact region to facilitate low-resistance contacts. A high quality two-dimensional electron gas is induced by a field-effect that is tunable over a density range of 6.5x10 10cm-2 to 2.6x1011cm-2 . Device design, fabrication, and low temperature (T=0.3K) characterization results are discussed. The demonstrated device-design overcomes several existing limitations in the fabrication of field-induced 2DEGs and might find utility in hosting nanostructures required for making spin qubits. The second broad segment describes our effort to correlate transport parameters measured at T=0.3K to the strength of the fractional quantum Hall state observed at nu=5/2 in the second Landau level of high-mobility GaAs/AlGaAs two dimensional

  13. Theoretical description of high-lying two-electrons states

    International Nuclear Information System (INIS)

    Greene, C.H.; Cavagnero, M.; Sadeghpour, H.R.

    1993-01-01

    Within the past two years, experiments on high-lying doubly-excited states in He and H- have shown spectra at energies near excited hydrogenic thresholds having principal quantum numbers in the range N=5--9. While they display some nontrivial complexities, the spectra are tremendously simpler than might be anticipated on the basis of independent electron models, in that only a small fraction of the total number of anticipated resonances are observed experimentally. Moreover, for principal quantum number N that are not too high, specifically N - , the resonance positions are described accurately by adiabatic calculations using hyperspherical coordinates and can be parametrized by a remarkably simple two-electron Rydberg formula. The observed propensity for excitation of only a small subset of the possible resonance states has been codified by several groups into approximate selection rules based on alternative (but apparently equivalent) classification schemes. Comparatively few attempts have been made at quantitative tests of the validity of these rules. The present review describes recent efforts to quantify their accuracy and limitations using R-matrix and quantum defect techniques, and Smith's delay-time matrix. Prospensity rules for exciting different degrees of freedom are found to differ greatly in their degree of validity

  14. Electronic States of IC60BA and PC71BM

    International Nuclear Information System (INIS)

    Sheng Chun-Qi; Wang Peng; Shen Ying; Li Wen-Jie; Li Hong-Nian; Zhang Wen-Hua; Zhu Jun-Fa; Lai Guo-Qiao

    2013-01-01

    We investigate the electronic states of IC 60 BA and PC 71 BM using first-principles calculations and photoelectron spectroscopy (PES) measurements. The energy level structures for all possible isomers are reported and compared with those of C 60 , C 70 and PC 61 BM. The attachment of the side chains can raise the LUMO energies and decrease the HOMO-LUMO gaps, and thus helps to increase the power-conversion efficiency of bulk heterojunction solar cells. In the PES studies, we prepared IC 60 BA and PC 71 BM films on Si:H(111) substrates to construct adsorbate/substrate interfaces describable with the integer charge-transfer (ICT) model. Successful measurements then revealed that one of the most important material properties for an electron acceptor, the energy of the negative integer charge-transfer state (E ICT− ), is 4.31 eV below the vacuum level for PC 71 BM. The E ICT− of IC 60 BA is smaller than 4.14 eV

  15. Single-molecule electronics: Cooling individual vibrational modes by the tunneling current.

    Science.gov (United States)

    Lykkebo, Jacob; Romano, Giuseppe; Gagliardi, Alessio; Pecchia, Alessandro; Solomon, Gemma C

    2016-03-21

    Electronic devices composed of single molecules constitute the ultimate limit in the continued downscaling of electronic components. A key challenge for single-molecule electronics is to control the temperature of these junctions. Controlling heating and cooling effects in individual vibrational modes can, in principle, be utilized to increase stability of single-molecule junctions under bias, to pump energy into particular vibrational modes to perform current-induced reactions, or to increase the resolution in inelastic electron tunneling spectroscopy by controlling the life-times of phonons in a molecule by suppressing absorption and external dissipation processes. Under bias the current and the molecule exchange energy, which typically results in heating of the molecule. However, the opposite process is also possible, where energy is extracted from the molecule by the tunneling current. Designing a molecular "heat sink" where a particular vibrational mode funnels heat out of the molecule and into the leads would be very desirable. It is even possible to imagine how the vibrational energy of the other vibrational modes could be funneled into the "cooling mode," given the right molecular design. Previous efforts to understand heating and cooling mechanisms in single molecule junctions have primarily been concerned with small models, where it is unclear which molecular systems they correspond to. In this paper, our focus is on suppressing heating and obtaining current-induced cooling in certain vibrational modes. Strategies for cooling vibrational modes in single-molecule junctions are presented, together with atomistic calculations based on those strategies. Cooling and reduced heating are observed for two different cooling schemes in calculations of atomistic single-molecule junctions.

  16. Does state-level context matter for individuals' knowledge about abortion, legality and health? Challenging the 'red states v. blue states' hypothesis.

    Science.gov (United States)

    Bessett, Danielle; Gerdts, Caitlin; Littman, Lisa L; Kavanaugh, Megan L; Norris, Alison

    2015-01-01

    Recently, the hypothesis that state-level political context influences individuals' cultural values--the 'red states v. blue states' hypothesis--has been invoked to explain the hyper-polarisation of politics in the USA. To test this hypothesis, we examined individuals' knowledge about abortion in relation to the political context of their current state of residence. Drawing from an internet-survey of 586 reproductive-age individuals in the USA, we assessed two types of abortion knowledge: health-related and legality. We found that state-level conservatism does not modify the existing relationships between individual predictors and each of the two types of abortion knowledge. Hence, our findings do not support the 'red states' versus 'blue states' hypothesis. Additionally, we find that knowledge about abortion's health effects in the USA is low: 7% of our sample thought abortion before 12 weeks gestation was illegal.

  17. COMPARATIVE ANALYSIS OF COMPETITIVE STATE ANXIETY AMONG TEAM SPORT AND INDIVIDUAL SPORT ATHLETES IN IRAN

    OpenAIRE

    Soltani Hossein; Hojati Zahra; Reza Attarzadeh Hossini Seyed

    2016-01-01

    Purpose: With respect to the fact that every sport field has its own special nature, the aim of present study was to compare competitive state anxiety among team sport and individual sport athletes in Iran. Material: The statistic sample included 120 male athletes, 60 athletes in individual sports (wrestling, taekwondo and karate) and 60 athletes in team sports (futsal, volleyball and basketball). The research instrument employed was the Persian version of the Competitive State Anxiety Invent...

  18. The relation between the (N) and (N-1) electrons atomic ground state

    International Nuclear Information System (INIS)

    Briet, P.

    1984-05-01

    The relation between the ground state of an N and (N-1) electrons atomic system are studied. We show that in some directions of the configuration space, the ratio of the N electrons atomic ground state to the one particle density is asymptotically equivalent to the (N-1) electrons atomic ground state

  19. Morphology, Composition, and Mixing State of Individual Aerosol Particles in Northeast China during Wintertime

    Directory of Open Access Journals (Sweden)

    Liang Xu

    2017-02-01

    Full Text Available Northeast China is located in a high latitude area of the world and undergoes a cold season that lasts six months each year. Recently, regional haze episodes with high concentrations of fine particles (PM2.5 have frequently been occurring in Northeast China during the heating period, but little information has been available. Aerosol particles were collected in winter at a site in a suburban county town (T1 and a site in a background rural area (T2. Morphology, size, elemental composition, and mixing state of individual aerosol particles were characterized by transmission electron microscopy (TEM. Aerosol particles were mainly composed of organic matter (OM and S-rich and certain amounts of soot and K-rich. OM represented the most abundant particles, accounting for 60.7% and 53.5% at the T1 and T2 sites, respectively. Abundant spherical OM particles were likely emitted directly from coal-burning stoves. Soot decreased from 16.9% at the T1 site to 4.6% at the T2 site and sulfate particles decrease from 35.9% at the T2 site to 15.7% at the T1 site, suggesting that long-range transport air masses experienced more aging processes and produced more secondary particles. Based on our investigations, we proposed that emissions from coal-burning stoves in most rural areas of the west part of Northeast China can induce regional haze episodes.

  20. Electronic individual identification of zebrafish using radio frequency identification (RFID) microtags.

    Science.gov (United States)

    Cousin, Xavier; Daouk, Tarek; Péan, Samuel; Lyphout, Laura; Schwartz, Marie-Elise; Bégout, Marie-Laure

    2012-08-15

    Although individual electronic tagging using passive integrated acoustic (PIT) tags is established, it is mainly for fish >60 mm in length and is unsuitable for fish of RFID) microtags (1 mm in diameter and 6 mm in length, with a mass of ~10 mg) to individually identify juvenile zebrafish (length 16-42 mm, mass 138-776 mg) for the first time, and studied the effects of intracoelomic implantation on fish survival and microtag loss, growth, spawning and exploratory behaviour. After 5.5 months, both high survival (82%) and low microtag loss (11%) were achieved. The smallest surviving fish weighed 178 mg, and success in microtag reading was 73% for the size class 350-450 mg (26 mm). Greater success was achieved when fish were larger at the time of tagging but no negative effects on growth were observed for any size class and some tagged fish spawned. No significant differences in behavioural responses could be detected between tagged fish and untagged controls after 2 months. Overall, the results suggest that the tagging method is highly suitable for fish as small as zebrafish juveniles. We think this method will provide significant advances for researchers of the ever-growing fish model community and more generally for all small-fish users. Tagging is essential when one needs to identify fish (e.g. particular genotypes with no external cue), to run longitudinal monitoring of individual biological traits (e.g. growth) or to repeat assays with the same individual at discrete points in time (e.g. behaviour studies). Such a method will find applications in physiology, genetics, behaviour and (eco)toxicology fields.

  1. Tunneling electron induced molecular electroluminescence from individual porphyrin J-aggregates

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qiushi; Zhang, Chao; Zhang, Yang, E-mail: zhyangnano@ustc.edu.cn, E-mail: zcdong@ustc.edu.cn; Zhang, Yao; Liao, Yuan; Dong, Zhenchao, E-mail: zhyangnano@ustc.edu.cn, E-mail: zcdong@ustc.edu.cn [Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2015-07-27

    We investigate molecular electroluminescence from individual tubular porphyrin J-aggregates on Au(111) by tunneling electron excitations in an ultrahigh-vacuum scanning tunneling microscope (STM). High-resolution STM images suggest a spiral tubular structure for the porphyrin J-aggregate with highly ordered “brickwork”-like arrangements. Such aggregated nanotube is found to behave like a self-decoupled molecular architecture and shows red-shifted electroluminescence characteristics of J-aggregates originated from the delocalized excitons. The positions of the emission peaks are found to shift slightly depending on the excitation sites, which, together with the changes in the observed spectral profiles with vibronic progressions, suggest a limited exciton coherence number within several molecules. The J-aggregate electroluminescence is also found unipolar, occurring only at negative sample voltages, which is presumably related to the junction asymmetry in the context of molecular excitations via the carrier injection mechanism.

  2. [Electronic and structural properties of individual nanometer-size supported metallic clusters

    International Nuclear Information System (INIS)

    Reifenberger, R.

    1993-01-01

    This report summarizes the work performed under contract DOE-FCO2-84ER45162. During the past ten years, our study of electron emission from laser-illuminated field emission tips has taken on a broader scope by addressing problems of direct interest to those concerned with the unique physical and chemical properties of nanometer-size clusters. The work performed has demonstrated that much needed data can be obtained on individual nanometer-size clusters supported on a wide-variety of different substrates. The work was performed in collaboration with R.P. Andres in the School of Chemical Engineering at Purdue University. The Multiple Expansion Cluster Source developed by Andres and his students was essential for producing the nanometer-size clusters studied. The following report features a discussion of these results. This report provides a motivation for studying the properties of nanometer-size clusters and summarizes the results obtained

  3. [Electronic and structural properties of individual nanometer-size supported metallic clusters]. Final performance report

    Energy Technology Data Exchange (ETDEWEB)

    Reifenberger, R.

    1993-09-01

    This report summarizes the work performed under contract DOE-FCO2-84ER45162. During the past ten years, our study of electron emission from laser-illuminated field emission tips has taken on a broader scope by addressing problems of direct interest to those concerned with the unique physical and chemical properties of nanometer-size clusters. The work performed has demonstrated that much needed data can be obtained on individual nanometer-size clusters supported on a wide-variety of different substrates. The work was performed in collaboration with R.P. Andres in the School of Chemical Engineering at Purdue University. The Multiple Expansion Cluster Source developed by Andres and his students was essential for producing the nanometer-size clusters studied. The following report features a discussion of these results. This report provides a motivation for studying the properties of nanometer-size clusters and summarizes the results obtained.

  4. Electron localization, polarons and clustered states in manganites

    International Nuclear Information System (INIS)

    Mannella, N.

    2004-01-01

    Full text: A recent multi-spectroscopic study of prototypical colossal magnetoresistance (CMR) compounds La 1-x Sr x MnO 3 (LSMO, x = 0.3, 0.4) using photoemission (PE), x-ray absorption (XAS), x-ray emission (XES) and extended x-ray absorption e structure (EXAFS) has exposed a dramatic change in the electronic structure on crossing the ferromagnetic-to-paramagnetic transition temperature (T C ). In particular, this investigation revealed an increase of the Mn magnetic moment by ca. 1 Bohr magneton and charge transfer to the Mn atom on crossing T C concomitant with the presence of Jahn-Teller distortions, thus providing direct evidence of lattice polaron formation. These results thus challenge the belief of some authors that the LSMO compounds are canonical double-exchange (DE) systems in which polaron formation is unimportant, and thus help to unify the theoretical description of the CMR oxides. The relationship of these data to other recent work suggesting electron localization, polarons and phase separation, along with additional measurements of magnetic susceptibility indicating the formation of ferromagnetic clusters in the metallic paramagnetic state above T C will be discussed

  5. The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier

    Energy Technology Data Exchange (ETDEWEB)

    J.G. Kulpin, K.J. Kleman, R.A. Legg

    2012-07-01

    A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

  6. Enabling Collaborative Analysis: State Evaluation Groups, the Electronic State File, and Collaborative Analysis Tools

    International Nuclear Information System (INIS)

    Eldridge, C.; Gagne, D.; Wilson, B.; Murray, J.; Gazze, C.; Feldman, Y.; Rorif, F.

    2015-01-01

    The timely collection and analysis of all safeguards relevant information is the key to drawing and maintaining soundly-based safeguards conclusions. In this regard, the IAEA has made multidisciplinary State Evaluation Groups (SEGs) central to this process. To date, SEGs have been established for all States and tasked with developing State-level approaches (including the identification of technical objectives), drafting annual implementation plans specifying the field and headquarters activities necessary to meet technical objectives, updating the State evaluation on an ongoing basis to incorporate new information, preparing an annual evaluation summary, and recommending a safeguards conclusion to IAEA senior management. To accomplish these tasks, SEGs need to be staffed with relevant expertise and empowered with tools that allow for collaborative access to, and analysis of, disparate information sets. To ensure SEGs have the requisite expertise, members are drawn from across the Department of Safeguards based on their knowledge of relevant data sets (e.g., nuclear material accountancy, material balance evaluation, environmental sampling, satellite imagery, open source information, etc.) or their relevant technical (e.g., fuel cycle) expertise. SEG members also require access to all available safeguards relevant data on the State. To facilitate this, the IAEA is also developing a common, secure platform where all safeguards information can be electronically stored and made available for analysis (an electronic State file). The structure of this SharePoint-based system supports IAEA information collection processes, enables collaborative analysis by SEGs, and provides for management insight and review. In addition to this common platform, the Agency is developing, deploying, and/or testing sophisticated data analysis tools that can synthesize information from diverse information sources, analyze diverse datasets from multiple viewpoints (e.g., temporal, geospatial

  7. Electron momentum spectroscopy of dimethyl ether taking account of nuclear dynamics in the electronic ground state

    International Nuclear Information System (INIS)

    Morini, Filippo; Deleuze, Michael Simon; Watanabe, Noboru; Kojima, Masataka; Takahashi, Masahiko

    2015-01-01

    The influence of nuclear dynamics in the electronic ground state on the (e,2e) momentum profiles of dimethyl ether has been analyzed using the harmonic analytical quantum mechanical and Born-Oppenheimer molecular dynamics approaches. In spite of fundamental methodological differences, results obtained with both approaches consistently demonstrate that molecular vibrations in the electronic ground state have a most appreciable influence on the momentum profiles associated to the 2b 1 , 6a 1 , 4b 2 , and 1a 2 orbitals. Taking this influence into account considerably improves the agreement between theoretical and newly obtained experimental momentum profiles, with improved statistical accuracy. Both approaches point out in particular the most appreciable role which is played by a few specific molecular vibrations of A 1 , B 1 , and B 2 symmetries, which correspond to C–H stretching and H–C–H bending modes. In line with the Herzberg-Teller principle, the influence of these molecular vibrations on the computed momentum profiles can be unraveled from considerations on the symmetry characteristics of orbitals and their energy spacing

  8. The electron-furfural scattering dynamics for 63 energetically open electronic states

    International Nuclear Information System (INIS)

    Costa, Romarly F. da; Varella, Márcio T. do N; Bettega, Márcio H. F.; Neves, Rafael F. C.; Lopes, Maria Cristina A.; Blanco, Francisco; García, Gustavo; Jones, Darryl B.

    2016-01-01

    We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (C 5 H 4 O 2 ). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (N open ) at either the static-exchange (N open  ch-SE) or the static-exchange-plus-polarisation (N open  ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channel coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections.

  9. The electron-furfural scattering dynamics for 63 energetically open electronic states

    Science.gov (United States)

    da Costa, Romarly F.; do N. Varella, Márcio T.; Bettega, Márcio H. F.; Neves, Rafael F. C.; Lopes, Maria Cristina A.; Blanco, Francisco; García, Gustavo; Jones, Darryl B.; Brunger, Michael J.; Lima, Marco A. P.

    2016-03-01

    We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (C5H4O2). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (Nopen) at either the static-exchange (Nopen ch-SE) or the static-exchange-plus-polarisation (Nopen ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channel coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections.

  10. The electron-furfural scattering dynamics for 63 energetically open electronic states

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Romarly F. da [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, Campinas, São Paulo 13083-859 (Brazil); Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210-580 (Brazil); Varella, Márcio T. do N [Instituto de Física, Universidade de São Paulo, CP 66318, São Paulo, São Paulo 05315-970 (Brazil); Bettega, Márcio H. F. [Departamento de Física, Universidade Federal do Paraná, CP 19044, Curitiba, Paraná 81531-990 (Brazil); Neves, Rafael F. C. [Instituto Federal do Sul de Minas Gerais, Campus Poços de Caldas, Minas Gerais (Brazil); Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-900 (Brazil); Lopes, Maria Cristina A. [Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-900 (Brazil); Blanco, Francisco [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid E-28040 (Spain); García, Gustavo [Instituto de Física Fundamental, CSIC, Serrano 113-bis, 28006 Madrid (Spain); Jones, Darryl B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); and others

    2016-03-28

    We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (C{sub 5}H{sub 4}O{sub 2}). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (N{sub open}) at either the static-exchange (N{sub open} ch-SE) or the static-exchange-plus-polarisation (N{sub open} ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channel coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections.

  11. Do psychobiosocial states mediate the relationship between perceived motivational climate and individual motivation in youngsters?

    Science.gov (United States)

    Bortoli, Laura; Bertollo, Maurizio; Filho, Edson; Robazza, Claudio

    2014-01-01

    Grounded in achievement goal theory and self-determination theory, this cross-sectional study examined the relationship between perceived motivational climate and individuals' motivation as well as the mediation effect of psychobiosocial states as conceptualised within the individual zones of optimal functioning (IZOF) model. Young students (N = 167, age range 14-15 years) taking part in physical education classes completed measures of teacher-initiated motivational climate, task and ego orientation, motivation and psychobiosocial states. Simple and serial mediation analyses indicated that a perceived mastery climate and individuals' task orientation were related to intrinsic motivation and identified regulation through the mediation of pleasant/functional psychobiosocial states. In contrast, a perceived performance climate was related to external regulation and amotivation through the mediation of unpleasant/dysfunctional psychobiosocial states. Regression analysis results also showed that discrete psychobiosocial states accounted for a significant proportion of variance in motivational variables. Taken together, findings highlight the role of psychobiosocial states as mediators of the relationship between motivational climate and an individual's motivation, and suggest that educators should consider a wide range of individual's functional and dysfunctional reactions deriving from their instructional activity.

  12. Solid-State Photomultiplier with Integrated Front End Electronics

    Science.gov (United States)

    Christian, James; Stapels, Christopher; Johnson, Erik; Mukhopadhyay, Sharmistha; Jie Chen, Xiao; Miskimen, Rory

    2009-10-01

    The instrumentation cost of physics experiments has been reduced per channel, by the use of solid-state detectors, but these cost-effective techniques have not been translated to scintillation-based detectors. When considering photodetectors, the cost per channel is determined by the use of high-voltage, analog-to-digital converters, BNC cables, and any other ancillary devices. The overhead associated with device operation limits the number of channels for the detector system, while potentially limiting the scope of physics that can be explored. The PRIMEX experiment at JLab, which is being designed to measure the radiative widths of the η and η' pseudo-scalar mesons for a more comprehensive understanding of QCD at low energies, is an example where CMOS solid-state photomultipliers (SSPMs) can be implemented. The ubiquitous nature of CMOS allows for on-chip signal processing to provide front-end electronics within the detector package. We present the results of the device development for the PRIMEX calorimeter, discussing the characteristics of SSPMs, the potential cost savings, and experimental results of on-chip signal processing.

  13. Quantification of entanglement entropies for doubly excited resonance states in two-electron atomic systems

    International Nuclear Information System (INIS)

    Ho, Yew Kam; Lin, Chien-Hao

    2015-01-01

    In this work, we study the quantum entanglement for doubly excited resonance states in two-electron atomic systems such as the H - and Ps - ions and the He atom by using highly correlated Hylleraas type functions The resonance states are determined by calculation of density of resonance states with the stabilization method. The spatial (electron-electron orbital) entanglement entropies (linear and von Neumann) for the low-lying doubly excited states are quantified using the Schmidt-Slater decomposition method. (paper)

  14. Metastable State Diamond Growth and its Applications to Electronic Devices.

    Science.gov (United States)

    Jeng, David Guang-Kai

    Diamond which consists of a dense array of carbon atoms joined by strong covalent bonds and formed into a tetrahedral crystal structure has remarkable mechanical, thermal, optical and electrical properties suitable for many industrial applications. With a proper type of doping, diamond is also an ideal semiconductor for high performance electronic devices. Unfortunately, natural diamond is rare and limited by its size and cost, it is not surprising that people continuously look for a synthetic replacement. It was believed for long time that graphite, another form of carbon, may be converted into diamond under high pressure and temperature. However, the exact condition of conversion was not clear. In 1939, O. I. Leipunsky developed an equilibrium phase diagram between graphite and diamond based on thermodynamic considerations. In the phase diagram, there is a low temperature (below 1000^ circC) and low pressure (below 1 atm) region in which diamond is metastable and graphite is stable, therefore establishes the conditions for the coexistence of the two species. Leipunsky's pioneer work opened the door for diamond synthesis. In 1955, the General Electric company (GE) was able to produce artificial diamond at 55k atm pressure and a temperature of 2000^ circC. Contrary to GE, B. Derjaguin and B. V. Spitzyn in Soviet Union, developed a method of growing diamonds at 1000^circC and at a much lower pressure in 1956. Since then, researchers, particularly in Soviet Union, are continuously looking for methods to grow diamond and diamond film at lower temperatures and pressures with slow but steady progress. It was only in the early 80's that the importance of growing diamond films had attracted the attentions of researchers in the Western world and in Japan. Recent progress in plasma physics and chemical vapor deposition techniques in integrated electronics technology have pushed the diamond growth in its metastable states into a new era. In this research, a microwave plasma

  15. 75 FR 3463 - Cross-Media Electronic Reporting Rule State Authorized Program Revision Approval: State of North...

    Science.gov (United States)

    2010-01-21

    ... consideration of the electronic document receiving systems that the state, tribe, or local government will use... for its Integrated Build Environment for Application Management (IBEAM) electronic document receiving... to assure that electronic documents are as legally dependable as their paper counterparts. Subpart D...

  16. Resting State EEG-based biometrics for individual identification using convolutional neural networks.

    Science.gov (United States)

    Lan Ma; Minett, James W; Blu, Thierry; Wang, William S-Y

    2015-08-01

    Biometrics is a growing field, which permits identification of individuals by means of unique physical features. Electroencephalography (EEG)-based biometrics utilizes the small intra-personal differences and large inter-personal differences between individuals' brainwave patterns. In the past, such methods have used features derived from manually-designed procedures for this purpose. Another possibility is to use convolutional neural networks (CNN) to automatically extract an individual's best and most unique neural features and conduct classification, using EEG data derived from both Resting State with Open Eyes (REO) and Resting State with Closed Eyes (REC). Results indicate that this CNN-based joint-optimized EEG-based Biometric System yields a high degree of accuracy of identification (88%) for 10-class classification. Furthermore, rich inter-personal difference can be found using a very low frequency band (0-2Hz). Additionally, results suggest that the temporal portions over which subjects can be individualized is less than 200 ms.

  17. The use of multiple imputation for the accurate measurements of individual feed intake by electronic feeders.

    Science.gov (United States)

    Jiao, S; Tiezzi, F; Huang, Y; Gray, K A; Maltecca, C

    2016-02-01

    Obtaining accurate individual feed intake records is the key first step in achieving genetic progress toward more efficient nutrient utilization in pigs. Feed intake records collected by electronic feeding systems contain errors (erroneous and abnormal values exceeding certain cutoff criteria), which are due to feeder malfunction or animal-feeder interaction. In this study, we examined the use of a novel data-editing strategy involving multiple imputation to minimize the impact of errors and missing values on the quality of feed intake data collected by an electronic feeding system. Accuracy of feed intake data adjustment obtained from the conventional linear mixed model (LMM) approach was compared with 2 alternative implementations of multiple imputation by chained equation, denoted as MI (multiple imputation) and MICE (multiple imputation by chained equation). The 3 methods were compared under 3 scenarios, where 5, 10, and 20% feed intake error rates were simulated. Each of the scenarios was replicated 5 times. Accuracy of the alternative error adjustment was measured as the correlation between the true daily feed intake (DFI; daily feed intake in the testing period) or true ADFI (the mean DFI across testing period) and the adjusted DFI or adjusted ADFI. In the editing process, error cutoff criteria are used to define if a feed intake visit contains errors. To investigate the possibility that the error cutoff criteria may affect any of the 3 methods, the simulation was repeated with 2 alternative error cutoff values. Multiple imputation methods outperformed the LMM approach in all scenarios with mean accuracies of 96.7, 93.5, and 90.2% obtained with MI and 96.8, 94.4, and 90.1% obtained with MICE compared with 91.0, 82.6, and 68.7% using LMM for DFI. Similar results were obtained for ADFI. Furthermore, multiple imputation methods consistently performed better than LMM regardless of the cutoff criteria applied to define errors. In conclusion, multiple imputation

  18. Observation of Zero-Dimensional States in a One-Dimensional Electron Interferometer

    NARCIS (Netherlands)

    Wees, B.J. van; Kouwenhoven, L.P.; Harmans, C.J.P.M.; Williamson, J.G.; Timmering, C.E.; Broekaart, M.E.I.; Foxon, C.T.; Harris, J.J.

    1989-01-01

    We have studied the electron transport in a one-dimensional electron interferometer. It consists of a disk-shaped two-dimensional electron gas, to which quantum point contacts are attached. Discrete zero-dimensional states are formed due to constructive interference of electron waves traveling along

  19. Evaluation of performance of electronic dosimeters for individual monitoring: tests in laboratory; Avaliacao do desempenho de dosimetros eletronicos para monitoracao individual: testes em laboratorio

    Energy Technology Data Exchange (ETDEWEB)

    Garzon, W.J.; Khoury, H.J.; Barros, V.S.M. de, E-mail: wjaramig@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife (Brazil). Departamento de Energia Nuclear. Laboratorio de Metrologia das Radiacoes Ionizantes; Medeiros, R.B. [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Departamento de Diagnostico por Imagem

    2015-07-01

    Electronic dosimeters based on direct ion storage technology are being widely used in many countries for individual monitoring in many applications of ionizing radiation. However, their use as routine dosimeter has been established in a few countries due to lack of accreditation or intercomparison programs. The objective of this study is to evaluate the performance of two direct íon storage dosimeters model available in the international market: the Miriom-Instadose-1 and RADOS DIS-1 to be eventually accepted for individual monitoring in Brazil. (author)

  20. Electronic cigarette initiation among minority youth in the United States.

    Science.gov (United States)

    Hammig, Bart; Daniel-Dobbs, Page; Blunt-Vinti, Heather

    2017-05-01

    Electronic cigarettes (e-cigarette) use among youth is a pressing public health issue, with prevalence of use surpassing that of tobacco cigarettes. While research concerning e-cigarettes has proliferated in recent years, there is a dearth of information regarding those whose first exposure to tobacco products was an e-cigarette. To examine factors associated with e-cigarette initiation among minority youth in the United States. Data on minority students in middle and high schools in the United States derived from the 2014 National Youth Tobacco Survey (NYTS) were sampled (weighted N = 27,294,454). We examined e-cigarette initiation among minority youth using logistic regression models to identify related factors. In 2014, 736,158 minority youth were e-cigarette initiators. Odds of e-cigarette initiation was highest among Hispanic youth [adjusted odds ratio (AOR) = 2.70; 95% confidence interval (CI) = 1.60-4.56]. Exposure to e-cigarette advertising (AOR = 1.64; 95% CI = 1.07-2.50), perceptions of little to no harm (AOR = 7.08; 95% CI = 4.03-12.46), and believing e-cigarettes were less addictive than tobacco (AOR = 2.15; 95% CI = 1.52-3.02) were associated with e-cigarette initiation. Odds of initiating e-cigarette use was highest among Hispanic youth. Among minority youth, e-cigarette initiation was associated with perceptions of harm and addiction potential, as well as exposure to e-cigarette advertising. Therefore, prevention efforts targeting minority youth who are at risk of becoming e-cigarette initiators may benefit by incorporating these factors into prevention campaigns.

  1. The Impact of State Medical Malpractice Reform on Individual-Level Health Care Expenditures.

    Science.gov (United States)

    Yu, Hao; Greenberg, Michael; Haviland, Amelia

    2017-12-01

    Past studies of the impact of state-level medical malpractice reforms on health spending produced mixed findings. Particularly salient is the evidence gap concerning the effect of different types of malpractice reform. This study aims to fill the gap. It extends the literature by examining the general population, not a subgroup or a specific health condition, and controlling for individual-level sociodemographic and health status. We merged the Database of State Tort Law Reforms with the Medical Expenditure Panel Survey between 1996 and 2012. We took a difference-in-differences approach to specify a two-part model for analyzing individual-level health spending. We applied the recycled prediction method and the bootstrapping technique to examining the difference in health spending growth between states with and without a reform. All expenditures were converted to 2010 U.S. dollars. Only two of the 10 major state-level malpractice reforms had significant impacts on the growth of individual-level health expenditures. The average annual expenditures in states with caps on attorney contingency fees increased less than that in states without the reform (p negligence rule, the average annual expenditures increased more in both states with a pure comparative fault reform (p < .05) and states with a comparative fault reform that barred recovery if the plaintiff's fault was equal to or greater than the defendant's (p < .05). A few state-level malpractice reforms had significantly affected the growth of individual-level health spending, and the direction and magnitude of the effects differed by type of reform. © Health Research and Educational Trust.

  2. Overlap of electron core states for very high compressions

    International Nuclear Information System (INIS)

    Straub, G.

    1985-01-01

    At normal density and for modest compressions, the electronic structure of a metal can be accurately described by treating the conduction electrons and their interactions with the usual methods of band theory. The core electrons remain essentially the same as for an isolated free atom and do not participate in the bonding forces responsible for creating a condensed phase. As the density increases, the core electrons begin to ''see'' one another as the overlap of the tails of wave functions can no longer be neglected. The electronic structure of the core electrons is responsible for an effective repulsive interaction that eventually becomes free-electron-like at very high compressions. The electronic structure of the interacting core electrons may be treated in a simple manner using the Atomic Surface Method (ASM). The ASM is a first-principles treatment of the electronic structure involving a rigorous integration of the Schroedinger equation within the atomic-sphere approximation. Solid phase wave functions are constructed from isolated atom wave functions and the band width W/sub l/ and the center of gravity of the band C/sub l/ are obtained from simple formulas. The ASM can also utilize analytic forms of the atomic wave functions and thus provide direct functional dependence of various aspects of the electronic structure. Of particular use in understanding the behavior of the core electrons, the ASM provides the analytic density dependence of the band widths and positions. 8 refs., 2 figs., 1 tab

  3. Cluster model calculations of the solid state materials electron structure

    International Nuclear Information System (INIS)

    Pelikan, P.; Biskupic, S.; Banacky, P.; Zajac, A.; Svrcek, A.; Noga, J.

    1997-01-01

    Materials of the general composition ACuO 2 are the parent compounds of so called infinite layer superconductors. In the paper presented the electron structure of the compounds CaCuO 2 , SrCuO2, Ca 0.86 Sr 0.14 CuO2 and Ca 0.26 Sr 0.74 CuO 2 were calculated. The cluster models consisting of 192 atoms were computed using quasi relativistic version of semiempirical INDO method. The obtained results indicate the strong ionicity of Ca/Sr-O bonds and high covalency of Cu-bonds. The width of energy gap at the Fermi level increases as follows: Ca 0.26 Sr 0.74 CuO 2 0.86 Sr 0.14 CuO2 2 . This order correlates with the fact that materials of the composition Ca x Sr 1-x CuO 2 have have the high temperatures of the superconductive transition (up to 110 K). Materials partially substituted by Sr 2+ have also the higher density of states in the close vicinity at the Fermi level that ai the additional condition for the possibility of superconductive transition. It was calculated the strong influence of the vibration motions to the energy gap at the Fermi level. (authors). 1 tabs., 2 figs., 10 refs

  4. Electron Beam Melting Manufacturing Technology for Individually Manufactured Jaw Prosthesis: A Case Report.

    Science.gov (United States)

    Suska, Felicia; Kjeller, Göran; Tarnow, Peter; Hryha, Eduard; Nyborg, Lars; Snis, Anders; Palmquist, Anders

    2016-08-01

    In the field of maxillofacial reconstruction, additive manufacturing technologies, specifically electron beam melting (EBM), offer clinicians the potential for patient-customized design of jaw prostheses, which match both load-bearing and esthetic demands. The technique allows an innovative, functional design, combining integrated porous regions for bone ingrowth and secondary biological fixation with solid load-bearing regions ensuring the biomechanical performance. A patient-specific mandibular prosthesis manufactured using EBM was successfully used to reconstruct a patient's mandibular defect after en bloc resection. Over a 9-month follow-up period, the patient had no complications. A short operating time, good esthetic outcome, and high level of patient satisfaction as measured by quality-of-life questionnaires-the European Organisation for Research and Treatment of Cancer QLQ-C30 (30-item quality-of-life core questionnaire) and H&N35 (head and neck cancer module)-were reported for this case. Individually planned and designed EBM-produced prostheses may be suggested as a possible future alternative to fibular grafts or other reconstructive methods. However, the role of porosity, the role of geometry, and the optimal combination of solid and porous parts, as well as surface properties in relation to soft tissues, should be carefully evaluated in long-term clinical trials. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Source identification of individual soot agglomerates in Arctic air by transmission electron microscopy

    Science.gov (United States)

    Weinbruch, S.; Benker, N.; Kandler, K.; Schütze, K.; Kling, K.; Berlinger, B.; Thomassen, Y.; Drotikova, T.; Kallenborn, R.

    2018-01-01

    Individual soot agglomerates collected at four different locations on the Arctic archipelago Svalbard (Norway) were characterised by transmission electron microscopy and energy-dispersive X-ray microanalysis. For source identification of the ambient soot agglomerates, samples from different local sources (coal burning power plants in Longyearbyen and Barentsburg, diesel and oil burning for power generation in Sveagruva and Ny Ålesund, cruise ship) as well as from other sources which may contribute to Arctic soot concentrations (biomass burning, aircraft emissions, diesel engines) were investigated. Diameter and graphene sheet separation distance of soot primary particles were found to be highly variable within each source and are not suited for source identification. In contrast, concentrations of the minor elements Si, P, K, Ca and Fe showed significant differences which can be used for source attribution. The presence/absence of externally mixed particle groups (fly ashes, tar balls, mercury particles) gives additional hints about the soot sources. Biomass/wood burning, ship emissions and coal burning in Barentsburg can be excluded as major source for ambient soot at Svalbard. The coal power plant in Longyearbyen is most likely a major source of soot in the settlement of Longyearbyen but does not contribute significantly to soot collected at the Global Atmosphere Watch station Zeppelin Mountain near Ny Ålesund. The most probable soot sources at Svalbard are aircraft emissions and diesel exhaust as well as long range transport of coal burning emissions.

  6. Electron Paramagnetic Resonance of a Single NV Nanodiamond Attached to an Individual Biomolecule.

    Science.gov (United States)

    Teeling-Smith, Richelle M; Jung, Young Woo; Scozzaro, Nicolas; Cardellino, Jeremy; Rampersaud, Isaac; North, Justin A; Šimon, Marek; Bhallamudi, Vidya P; Rampersaud, Arfaan; Johnston-Halperin, Ezekiel; Poirier, Michael G; Hammel, P Chris

    2016-05-10

    Electron paramagnetic resonance (EPR), an established and powerful methodology for studying atomic-scale biomolecular structure and dynamics, typically requires in excess of 10(12) labeled biomolecules. Single-molecule measurements provide improved insights into heterogeneous behaviors that can be masked in ensemble measurements and are often essential for illuminating the molecular mechanisms behind the function of a biomolecule. Here, we report EPR measurements of a single labeled biomolecule. We selectively label an individual double-stranded DNA molecule with a single nanodiamond containing nitrogen-vacancy centers, and optically detect the paramagnetic resonance of nitrogen-vacancy spins in the nanodiamond probe. Analysis of the spectrum reveals that the nanodiamond probe has complete rotational freedom and that the characteristic timescale for reorientation of the nanodiamond probe is slow compared with the transverse spin relaxation time. This demonstration of EPR spectroscopy of a single nanodiamond-labeled DNA provides the foundation for the development of single-molecule magnetic resonance studies of complex biomolecular systems. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  7. In situ tensile testing of individual Co nanowires inside a scanning electron microscope

    International Nuclear Information System (INIS)

    Zhang Dongfeng; Breguet, Jean-Marc; Clavel, Reymond; Phillippe, Laetitia; Utke, Ivo; Michler, Johann

    2009-01-01

    Uniaxial quasi-static tensile testing on individual nanocrystalline Co nanowires (NWs), synthesized by electrochemical deposition process (EDP) in porous templates, was performed inside a scanning electron microscope (SEM) using a microfabricated tensile stage consisting of a comb drive actuator and a clamped-clamped beam force sensor. A 'three-beam structure' was fabricated by focused ion beam induced deposition (FIBID) on the stage, from which the specimen elongation and the tensile force could be measured simultaneously from SEM images at high magnification. A novel strategy of modifying device topography, e.g. in the form of trenches and pillars, was proposed to facilitate in situ SEM pick-and-place nanomanipulation, which could achieve a high yield of about 80% and reduce the difficulties in specimen preparation for tensile testing at the nanoscale. The measured apparent Young's modulus (75.3 ± 14.6) GPa and tensile strength (1.6 ± 0.4) GPa are significantly lower than the bulk modulus and the theoretical strength of monocrystalline samples, respectively. This result is important for designing Co NW-based devices. The origins of these distinctions are discussed in terms of the stiffnesses of the soldering portions, specimen misalignment, microstructure of the NWs and the experimental measurement uncertainty.

  8. Ultrafast electronic relaxation of excited state vitamin B12 in the gas phase

    International Nuclear Information System (INIS)

    Shafizadeh, Niloufar; Poisson, Lionel; Soep, Benoit

    2008-01-01

    The time evolution of electronically excited vitamin B 12 (cyanocobalamin) has been observed for the first time in the gas phase. It reveals an ultrafast decay to a state corresponding to metal excitation. This decay is interpreted as resulting from a ring to metal electron transfer. This opens the observation of the excited state of other complex biomimetic systems in the gas phase, the key to the characterisation of their complex evolution through excited electronic states

  9. Anomalous Ground State of the Electrons in Nano-confined Water

    Science.gov (United States)

    2016-06-13

    Anomalous ground state of the electrons in nano -confined water G. F. Reiter1*, Aniruddha Deb2*, Y. Sakurai3, M. Itou3, V. G. Krishnan4, S. J...electronic ground state of nano -confined water must be responsible for these anomalies but has so far not been investigated. We show here for the first time...using x-ray Compton scattering and a computational model, that the ground state configuration of the valence electrons in a particular nano

  10. Differences between individual and societal health state valuations: any link with personality?

    Science.gov (United States)

    Chapman, Benjamin P; Franks, Peter; Duberstein, Paul R; Jerant, Anthony

    2009-08-01

    The concept of "adaptation" has been proposed to account for differences between individual and societal valuations of specific health states in patients with chronic diseases. Little is known about psychological indices of adaptational capacity, which may predict differences in individual and societal valuations of health states. We investigated whether such differences were partially explained by personality traits in chronic disease patients. Analysis of baseline data of randomized controlled trial. Three hundred seventy patients with chronic disease. The NEO-five factor inventory measure of personality, EuroQoL-5D (EQ-5D) societal-based, and the EQ visual analogue scale individually-based measures of health valuation. Regression analyses modeled Dev, a measure of difference between the EQ-Visual Analogue Scale and EQ-5D, as a function of personality traits, sociodemographic factors, and chronic diseases. Individual valuations were significantly and clinically higher than societal valuations among patients in the second and third quartile of conscientiousness (Dev = 0.08, P = 0.01); among covariates, only depression (Dev = -0.04, P = 0.046) was also associated with Dev. Compared with societal valuations of a given health state, persons at higher quartiles of conscientiousness report less disutility associated with poor health. The effect is roughly twice that of some estimates of minimally important clinical differences on the EQ-5D and of depression. Although useful at the aggregate level, societal preference measures may systematically undervalue the health states of more conscientious individuals. Future work should examine the impact this has on individual patient outcome evaluation in clinical studies.

  11. Athermal electron distribution probed by femtosecond multiphoton photoemission from image potential states

    International Nuclear Information System (INIS)

    Ferrini, Gabriele; Giannetti, Claudio; Pagliara, Stefania; Banfi, Francesco; Galimberti, Gianluca; Parmigiani, Fulvio

    2005-01-01

    Image potential states are populated through indirect, scattering-mediated multiphoton absorption induced by femtosecond laser pulses and revealed by single-photon photoemission. The measured effective mass is significantly different from that obtained with direct, resonant population. These features reveal a strong coupling of the electrons residing in the image potential state, outside the solid, with the underlying hot electron population created by the laser pulse. The coupling is mediated by a many-body scattering interaction between the image potential state electrons and bulk electrons in highly excited states

  12. Does the Higgs mechanism favour electron-electron bound states in Maxwell-Chern-Simons QED3?

    International Nuclear Information System (INIS)

    Belich, Humberto; Helayeel-Neto, Jose Abdalla; Ferreira Junior, Manoel Messias

    2000-01-01

    Full text follows: We show that low-energy electron-electron bound states appear in the Maxwell-Chern-Simons (MCS) planar QED. In spite of the repulsive interaction mediated by the MCS gauge field, a net attractive interaction stems due to the Higgs mechanism through an Yukawa-type interaction. The spontaneous breaking of a local U(1)-symmetry is realized by a γ 6 -type potential. We conclude, by using the Schroedinger equation associated to the net attractive scattering potential, that electron-electron bound states arise in the model. Therefore, the Higgs mechanism overcomes the difficulties found out by Girotti et al. (Phys. Rev. Lett. 69 (1992) 2623) in searching for bound states in the MCS planar QED. (author)

  13. National estimates of healthcare utilization by individuals with hepatitis C virus infection in the United States.

    Science.gov (United States)

    Galbraith, James W; Donnelly, John P; Franco, Ricardo A; Overton, Edgar T; Rodgers, Joel B; Wang, Henry E

    2014-09-15

    Hepatitis C virus (HCV) infection is a major public health problem in the United States. Although prior studies have evaluated the HCV-related healthcare burden, these studies examined a single treatment setting and did not account for the growing "baby boomer" population (individuals born during 1945-1965). Data from the National Ambulatory Medical Care Survey, the National Hospital Ambulatory Medical Care Survey, and the Nationwide Inpatient Sample were analyzed. We sought to characterize healthcare utilization by individuals infected with HCV in the United States, examining adult (≥18 years) outpatient, emergency department (ED), and inpatient visits among individuals with HCV diagnosis for the period 2001-2010. Key subgroups included persons born before 1945 (older), between 1945 and 1965 (baby boomer), and after 1965 (younger). Individuals with HCV infection were responsible for >2.3 million outpatient, 73 000 ED, and 475 000 inpatient visits annually. Persons in the baby boomer cohort accounted for 72.5%, 67.6%, and 70.7% of care episodes in these settings, respectively. Whereas the number of outpatient visits remained stable during the study period, inpatient admissions among HCV-infected baby boomers increased by >60%. Inpatient stays totaled 2.8 million days and cost >$15 billion annually. Nonwhites, uninsured individuals, and individuals receiving publicly funded health insurance were disproportionately affected in all healthcare settings. Individuals with HCV infection are large users of outpatient, ED, and inpatient health services. Resource use is highest and increasing in the baby boomer generation. These observations illuminate the public health burden of HCV infection in the United States. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  14. State selective single-electron capture in O6++Nacollisions

    NARCIS (Netherlands)

    Knoop, S; Keim, M; Ludde, HJ; Kirchner, T; Morgenstern, [No Value; Hoekstra, R

    2005-01-01

    Single-electron capture in O6+ + Na collisions at 1-9 keV/amu collision energy has been studied both experimentally and theoretically. Partial cross sections for electron capture into n = 5, 6, 7, 8 and n >= 9 have been obtained from target recoil momenta measured by the technique of MOTRIMS and are

  15. Electron dynamics in solid state via time varying wavevectors

    Science.gov (United States)

    Khaneja, Navin

    2018-06-01

    In this paper, we study electron wavepacket dynamics in electric and magnetic fields. We rigorously derive the semiclassical equations of electron dynamics in electric and magnetic fields. We do it both for free electron and electron in a periodic potential. We do this by introducing time varying wavevectors k(t). In the presence of magnetic field, our wavepacket reproduces the classical cyclotron orbits once the origin of the Schröedinger equation is correctly chosen to be center of cyclotron orbit. In the presence of both electric and magnetic fields, our equations for wavepacket dynamics differ from classical Lorentz force equations. We show that in a periodic potential, on application of electric field, the electron wave function adiabatically follows the wavefunction of a time varying Bloch wavevector k(t), with its energies suitably shifted with time. We derive the effective mass equation and discuss conduction in conductors and insulators.

  16. All Electron ab initio Investigations of the Three Lowest Lying Electronic States of the RuC Molecule

    DEFF Research Database (Denmark)

    Shim, Irene; Gingerich, K. A.

    2000-01-01

    The three lowest-lying electronic states of RuC, (1)Sigma(+), (3)Delta, and (1)Delta, have been investigated by performing all-electron ab initio multi-configuration self-consistent-field (CASSCF) and multi-reference configuration interaction (MRCI) calculations including relativistic corrections....... The electronic ground state is derived as (1)Sigma(+) with the spectroscopic constants r(e) = 1.616 Angstrom and omega(e) = 1085 cm(-1). The lowest-lying excited state, (3)Delta, has r(e) = 1.632 Angstrom, omega(e) = 1063 cm(-1), and T-e = 912 cm(-1). These results are consistent with recent spectroscopic values....... The chemical bonds in all three lowest-lying states are triple bonds composed of one sigma and two pi bonds. (C) 2000 Elsevier Science B.V. All rights reserved....

  17. Proton-coupled electron transfer versus hydrogen atom transfer: generation of charge-localized diabatic states.

    Science.gov (United States)

    Sirjoosingh, Andrew; Hammes-Schiffer, Sharon

    2011-03-24

    The distinction between proton-coupled electron transfer (PCET) and hydrogen atom transfer (HAT) mechanisms is important for the characterization of many chemical and biological processes. PCET and HAT mechanisms can be differentiated in terms of electronically nonadiabatic and adiabatic proton transfer, respectively. In this paper, quantitative diagnostics to evaluate the degree of electron-proton nonadiabaticity are presented. Moreover, the connection between the degree of electron-proton nonadiabaticity and the physical characteristics distinguishing PCET from HAT, namely, the extent of electronic charge redistribution, is clarified. In addition, a rigorous diabatization scheme for transforming the adiabatic electronic states into charge-localized diabatic states for PCET reactions is presented. These diabatic states are constructed to ensure that the first-order nonadiabatic couplings with respect to the one-dimensional transferring hydrogen coordinate vanish exactly. Application of these approaches to the phenoxyl-phenol and benzyl-toluene systems characterizes the former as PCET and the latter as HAT. The diabatic states generated for the phenoxyl-phenol system possess physically meaningful, localized electronic charge distributions that are relatively invariant along the hydrogen coordinate. These diabatic electronic states can be combined with the associated proton vibrational states to generate the reactant and product electron-proton vibronic states that form the basis of nonadiabatic PCET theories. Furthermore, these vibronic states and the corresponding vibronic couplings may be used to calculate rate constants and kinetic isotope effects of PCET reactions.

  18. Bayesian analysis of multi-state data with individual covariates for estimating genetic effects on demography

    Science.gov (United States)

    Converse, Sarah J.; Royle, J. Andrew; Urbanek, Richard P.

    2012-01-01

    Inbreeding depression is frequently a concern of managers interested in restoring endangered species. Decisions to reduce the potential for inbreeding depression by balancing genotypic contributions to reintroduced populations may exact a cost on long-term demographic performance of the population if those decisions result in reduced numbers of animals released and/or restriction of particularly successful genotypes (i.e., heritable traits of particular family lines). As part of an effort to restore a migratory flock of Whooping Cranes (Grus americana) to eastern North America using the offspring of captive breeders, we obtained a unique dataset which includes post-release mark-recapture data, as well as the pedigree of each released individual. We developed a Bayesian formulation of a multi-state model to analyze radio-telemetry, band-resight, and dead recovery data on reintroduced individuals, in order to track survival and breeding state transitions. We used studbook-based individual covariates to examine the comparative evidence for and degree of effects of inbreeding, genotype, and genotype quality on post-release survival of reintroduced individuals. We demonstrate implementation of the Bayesian multi-state model, which allows for the integration of imperfect detection, multiple data types, random effects, and individual- and time-dependent covariates. Our results provide only weak evidence for an effect of the quality of an individual's genotype in captivity on post-release survival as well as for an effect of inbreeding on post-release survival. We plan to integrate our results into a decision-analytic modeling framework that can explicitly examine tradeoffs between the effects of inbreeding and the effects of genotype and demographic stochasticity on population establishment.

  19. Horizontal and vertical individualism and collectivism among college students in the United States, Taiwan, and Argentina.

    Science.gov (United States)

    Chiou, J S

    2001-10-01

    Among college students in the United States, Taiwan, and Argentina, the author examined the strength of 4 cultural patterns (horizontal collectivism, vertical collectivism, horizontal individualism, vertical individualism; H. C. Triandis, 1995). A 3-group confirmatory factor analysis established the measurement equivalence among the 3 samples before the comparison. The Taiwanese and the Argentine samples were more vertically collectivist than the U.S. sample. The U.S. and the Taiwanese samples were more vertically individualistic than the Argentine sample. The U.S. sample was more horizontally individualistic than the Argentine sample, which, in turn, was more horizontally individualistic than the Taiwanese sample.

  20. Dynamics of photoionization from molecular electronic wavepacket states in intense pulse laser fields: A nonadiabatic electron wavepacket study.

    Science.gov (United States)

    Matsuoka, Takahide; Takatsuka, Kazuo

    2017-04-07

    A theory for dynamics of molecular photoionization from nonadiabatic electron wavepackets driven by intense pulse lasers is proposed. Time evolution of photoelectron distribution is evaluated in terms of out-going electron flux (current of the probability density of electrons) that has kinetic energy high enough to recede from the molecular system. The relevant electron flux is in turn evaluated with the complex-valued electronic wavefunctions that are time evolved in nonadiabatic electron wavepacket dynamics in laser fields. To uniquely rebuild such wavefunctions with its electronic population being lost by ionization, we adopt the complex-valued natural orbitals emerging from the electron density as building blocks of the total wavefunction. The method has been implemented into a quantum chemistry code, which is based on configuration state mixing for polyatomic molecules. Some of the practical aspects needed for its application will be presented. As a first illustrative example, we show the results of hydrogen molecule and its isotope substitutes (HD and DD), which are photoionized by a two-cycle pulse laser. Photon emission spectrum associated with above threshold ionization is also shown. Another example is taken from photoionization dynamics from an excited state of a water molecule. Qualitatively significant effects of nonadiabatic interaction on the photoelectron spectrum are demonstrated.

  1. Electron states in thulium and other rare-earth metals

    International Nuclear Information System (INIS)

    Strange, P.; Fairbairn, W.M.; Lee, P.M.

    1983-01-01

    The LMTO method has been applied to calculate band structures for the heavier rare-earth metals. The calculations are relativistic. Thulium in particular has been considered, where a frozen core approximation is used, and the outer electrons are treated selfconsistently. Problems associated with the localisation and interactions of the 4f electrons are discussed. Teh comparisons between experimental data and calculated quantities are encouraging, but more data on high-purity single crystals would be helpful. (author)

  2. An exciton approach to the excited states of two electron atoms. I Formalism and interpretation

    International Nuclear Information System (INIS)

    Schipper, P.E.

    1985-01-01

    The exciton model is formally applied to a description of the excited states of two electron atoms with the explicit inclusion of exchange. The model leads to a conceptually simple framework for the discussion of the electronic properties of the archetypical atomic electron pair

  3. Equation of state for electron gas in the presence of electron-positron pairs

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, D; Nomoto, K [Tokyo Univ. (Japan). Coll. of General Education

    1975-12-01

    Fermi-Dirac integrals for partially relativistic, partially degenerate, electron gas are tabulated, especially for the region of electron-positron pair-creation in equilibrium with radiation field. Electrons are treated to be non-interacting particles. Independent entries for the table are non-dimensional temperature and a degeneracy parameter which is related directly with matter density. Thermodynamical quantities and their partial derivatives with respect to density and temperature are also given in table, which are intended for use in computing stellar evolution by means of a Henyey-type technique. This table is a supplement to one published earlier, in which only electrons were taken into account explicitly.

  4. Deconvolution of overlapping features in electron energy-loss spectra: the determination of absolute differential cross sections for electron-impact excitation of electronic states of molecules

    International Nuclear Information System (INIS)

    Campbell, L.; Brunger, M.J.; Teubner, O.J.P.; Mojarrabi, B.

    1996-06-01

    A set of three computer programs is reported which allow for the deconvolution of overlapping molecular electronic state structure in electron energy-loss spectra, even in highly perturbed systems. This procedure enables extraction of absolute differential cross sections for electron-impact excitation of electronic states of diatomic molecules from electron energy-loss spectra. The first code in the sequence uses the Rydberg-Klein-Rees procedure to generate potential energy curves from spectroscopic constants, while the second calculates Franck-Condon factors by numerical solution of the Schroedinger equation, given the potential energy curves. The third, given these Franck-Condon factors, the previously calculated relevant energies for the vibrational levels of the respective electronic states and the experimental energy-loss spectra, extracts the differential cross sections for each state. Each program can be run independently, or the three can run in sequence to determine these cross sections from the spectroscopic constants and the experimental energy-loss spectra. The application of these programs to the specific case of electron scattering from nitric oxide (NO) is demonstrated. 25 refs., 2 tabs., 2 figs

  5. Correlative scanning-transmission electron microscopy reveals that a chimeric flavivirus is released as individual particles in secretory vesicles.

    Directory of Open Access Journals (Sweden)

    Julien Burlaud-Gaillard

    Full Text Available The intracellular morphogenesis of flaviviruses has been well described, but flavivirus release from the host cell remains poorly documented. We took advantage of the optimized production of an attenuated chimeric yellow fever/dengue virus for vaccine purposes to study this phenomenon by microscopic approaches. Scanning electron microscopy (SEM showed the release of numerous viral particles at the cell surface through a short-lived process. For transmission electron microscopy (TEM studies of the intracellular ultrastructure of the small number of cells releasing viral particles at a given time, we developed a new correlative microscopy method: CSEMTEM (for correlative scanning electron microscopy - transmission electron microscopy. CSEMTEM analysis suggested that chimeric flavivirus particles were released as individual particles, in small exocytosis vesicles, via a regulated secretory pathway. Our morphological findings provide new insight into interactions between flaviviruses and cells and demonstrate that CSEMTEM is a useful new method, complementary to SEM observations of biological events by intracellular TEM investigations.

  6. Ethics, Economics and Dentistry for Individuals with Disabilities in New York State.

    Science.gov (United States)

    Waldman, H Barry; Perlman, Steven P

    2016-03-01

    The ADA Principles of Ethics and Code of Professional Conduct is an expression of the obligation occurring between the profession and society to meet the oral health needs of the public. At a time of economic concerns for the profession, suggestions are made to bring together the ethics of the profession and the need to expand services to underserved populations, including individuals with disabilities and the poor. The profession's effort to secure economic support for such an effort is possible with increased legislative awareness of the magnitude of the problem. To this end, the number of individuals with disabilities was developed for each Congressional district in New York State in an effort to challenge members of Congress to recognize the need in terms of their constituents, rather than in terms of the tens of millions with disabilities in the United States-which become "just numbers," not actual people.

  7. COMPARATIVE ANALYSIS OF COMPETITIVE STATE ANXIETY AMONG TEAM SPORT AND INDIVIDUAL SPORT ATHLETES IN IRAN

    Directory of Open Access Journals (Sweden)

    Soltani Hossein

    2016-10-01

    Full Text Available Purpose: With respect to the fact that every sport field has its own special nature, the aim of present study was to compare competitive state anxiety among team sport and individual sport athletes in Iran. Material: The statistic sample included 120 male athletes, 60 athletes in individual sports (wrestling, taekwondo and karate and 60 athletes in team sports (futsal, volleyball and basketball. The research instrument employed was the Persian version of the Competitive State Anxiety Inventory-2. This inventory was distributed among the subjects about 30 minutes before the first competition. Finally by one-way ANOVA data was analyzed. Results: The results indicated that the mean score of somatic anxiety and cognitive anxiety among individual sport athletes was significantly higher than that of team sport athletes (p0.05. Conclusion: It seems the being part of a team alleviates some of the pressure experienced by those who compete alone. It seems the individual sport athletes may be more exposed to evaluation and more engaged in their own skills and abilities than team sport athletes given that responsibility for performance is not distributed across several performers.

  8. Individual differences in the interoceptive states of hunger, fullness and thirst.

    Science.gov (United States)

    Stevenson, Richard J; Mahmut, Mehmet; Rooney, Kieron

    2015-12-01

    Interoception is the ability to perceive internal bodily states. This involves the detection and awareness of static and changing afferent signals from the viscera, motivational states, affective reactions, and associated cognitions. We examined whether there are individual differences in any or all of these aspects of ingestion-related interoception and their possible causes. Individual variation in almost all aspects of interoception was documented for hunger, fullness and thirst - including how participants use, prioritise and integrate visceral, motivational, affective and cognitive information. Individual differences may arise from multiple causes, including genetic influences, developmental changes hypothesised to result from child feeding practices, and from conditions such as depression, anxiety, eating disorders and certain subtypes of obesity. A nutritionally poor diet, and dietary restraint, may also affect ingestion-related interoception. Finally, certain forms of brain injury, notably to the medial temporal lobes are associated with impaired ingestion-related interoception. We conclude by examining the practical and theoretical consequences of these individual differences. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Electronic states and nature of bonding of the molecule PdGe by all electron ab initio HF–CI calculations and mass spectrometric equilibrium experiments

    DEFF Research Database (Denmark)

    Shim, Irene; Kingcade, Joseph E. , Jr.; Gingerich, Karl A.

    1986-01-01

    In the present work we present all-electron ab initio Hartree–Fock (HF) and configuration interaction (CI) calculations of six electronic states of the PdGe molecule. The molecule is predicted to have a 3Pi ground state and two low-lying excited states 3Sigma− and 1Sigma+. The electronic structure...

  10. Quantitative detection of gold nanoparticles on individual, unstained cancer cells by Scanning Electron Microscopy

    NARCIS (Netherlands)

    Hartsuiker, Liesbeth; van Es, Peter; Petersen, Wilhelmina; van Leeuwen, Ton; Terstappen, Leonardus Wendelinus Mathias Marie; Otto, Cornelis

    2011-01-01

    Gold nanoparticles are rapidly emerging for use in biomedical applications. Characterization of the interaction and delivery of nanoparticles to cells through microscopy is important. Scanning electron microscopes have the intrinsic resolution to visualize gold nanoparticles on cells. A novel sample

  11. Quantitative detection of gold nanoparticles on individual, unstained cancer cells by scanning electron microscopy

    NARCIS (Netherlands)

    Hartsuiker, L.; van Es, P.; Petersen, W.; van Leeuwen, T. G.; Terstappen, L. W. M. M.; Otto, C.

    2011-01-01

    Gold nanoparticles are rapidly emerging for use in biomedical applications. Characterization of the interaction and delivery of nanoparticles to cells through microscopy is important. Scanning electron microscopes have the intrinsic resolution to visualize gold nanoparticles on cells. A novel sample

  12. Contribution from individual nearby sources to the spectrum of high-energy cosmic-ray electrons

    International Nuclear Information System (INIS)

    Sedrati, R.; Attallah, R.

    2014-01-01

    In the last few years, very important data on high-energy cosmic-ray electrons and positrons from high-precision space-born and ground-based experiments have attracted a great deal of interest. These particles represent a unique probe for studying local comic-ray accelerators because they lose energy very rapidly. These energy losses reduce the lifetime so drastically that high-energy cosmic-ray electrons can attain the Earth only from rather local astrophysical sources. This work aims at calculating, by means of Monte Carlo simulation, the contribution from some known nearby astrophysical sources to the cosmic-ray electron/positron spectra at high energy (≥10GeV). The background to the electron energy spectrum from distant sources is determined with the help of the GALPROP code. The obtained numerical results are compared with a set of experimental data

  13. Contribution from individual nearby sources to the spectrum of high-energy cosmic-ray electrons

    Energy Technology Data Exchange (ETDEWEB)

    Sedrati, R., E-mail: rafik.sedrati@univ-annaba.org; Attallah, R.

    2014-04-01

    In the last few years, very important data on high-energy cosmic-ray electrons and positrons from high-precision space-born and ground-based experiments have attracted a great deal of interest. These particles represent a unique probe for studying local comic-ray accelerators because they lose energy very rapidly. These energy losses reduce the lifetime so drastically that high-energy cosmic-ray electrons can attain the Earth only from rather local astrophysical sources. This work aims at calculating, by means of Monte Carlo simulation, the contribution from some known nearby astrophysical sources to the cosmic-ray electron/positron spectra at high energy (≥10GeV). The background to the electron energy spectrum from distant sources is determined with the help of the GALPROP code. The obtained numerical results are compared with a set of experimental data.

  14. All-electron ab initio investigation of the electronic states of the PdC molecule

    DEFF Research Database (Denmark)

    Shim, Irene; Gingerich, Karl A.

    2001-01-01

    The electronic structure of transition metal containing molecules are extremely complicated and extensive calculations are required for reliable descriptions. In spite of this the results can often be interpreted in simple terms. The electronic structure of PdC is consistent with the molecular or...

  15. S-band 300 W pulsed solid state microwave amplifier development for driving high power klystrons for electron accelerators

    International Nuclear Information System (INIS)

    Mohania, Praveen; Shrivastava, Purushottam; Hannurkar, P.R.

    2005-01-01

    S-Band Microwave electron accelerators like microtrons and linear accelerators need pulsed microwaves from few megawatts to tens of megawatts to accelerator the electrons to desired energy and intensity. Klystron tube based driver amplifiers were used to drive the high power klystrons, which need microwave power from few tens of watts to 1 kW depending on tube output power and gain. A endeavour was initiated at Centre for Advanced Technology to develop state of art solid state S-band microwave amplifiers indigenously to drive the klystron tubes. A modular design approach was used and individual modules up to 160 W power levels were developed and tested. Finally combining 160 W modules will give up to 300 W output power. Several more modules can be combined to achieve even high power levels. Present paper describes the developmental efforts of 300 W S-band solid-state amplifiers and related microwave technologies. (author)

  16. Electronic states of emodin and its conjugate base

    DEFF Research Database (Denmark)

    Nguyen, Son Chi; Hansen, Bjarke Knud Vilster; Hoffmann, Søren Vrønning

    2008-01-01

    The electronic transitions of emodin (1,3,8-trihydroxy-6-methyl-9,10-anthraquinone, E) and its conjugate base (3-oxido-6-methyl-1,8-dihydroxy-9,10-anthraquinone, Ecb) were investigated by UV-Vis linear dichroism (LD) spectroscopy on molecular samples aligned in stretched poly(vinylalcohol). The e......The electronic transitions of emodin (1,3,8-trihydroxy-6-methyl-9,10-anthraquinone, E) and its conjugate base (3-oxido-6-methyl-1,8-dihydroxy-9,10-anthraquinone, Ecb) were investigated by UV-Vis linear dichroism (LD) spectroscopy on molecular samples aligned in stretched poly...

  17. Laboratory Measurements on Charging of Individual Micron-Size Apollo-11 Dust Grains by Secondary Electron Emissions

    Science.gov (United States)

    Tankosic, D.; Abbas, M. M.

    2012-01-01

    Observations made during Apollo missions, as well as theoretical models indicate that the lunar surface and dust grains are electrostatically charged, levitated and transported. Lunar dust grains are charged by UV photoelectric emissions on the lunar dayside and by the impact of the solar wind electrons on the nightside. The knowledge of charging properties of individual lunar dust grains is important for developing appropriate theoretical models and mitigating strategies. Currently, very limited experimental data are available for charging of individual micron-size size lunar dust grains in particular by low energy electron impact. However, experimental results based on extensive laboratory measurements on the charging of individual 0.2-13 micron size lunar dust grains by the secondary electron emissions (SEE) have been presented in a recent publication. The SEE process of charging of micron-size dust grains, however, is found to be very complex phenomena with strong particle size dependence. In this paper we present some examples of the complex nature of the SEE properties of positively charged individual lunar dust grains levitated in an electrodynamic balance (EDB), and show that they remain unaffected by the variation of the AC field employed in the above mentioned measurements.

  18. Electronic states of 1,4-bis(phenylethynyl)benzene

    DEFF Research Database (Denmark)

    Nguyen, Duy Duc; Jones, Nykola; Hoffmann, Søren Vrønning

    2012-01-01

    The electronic transitions of 1,4-bis(phenylethynyl)benzene (BPEB) were investigated by UV synchrotron radiation linear dichroism (SRLD) spectroscopy in the range 25,000 – 58,000 cm–1 (400 – 170 nm) on molecular samples aligned in stretched polyethylene. The investigation was supported by variable...

  19. Ground state of the electron gas by a stochastic method

    International Nuclear Information System (INIS)

    Ceperley, D.M.; Alder, B.J.

    1980-05-01

    An exact stochastic simulation of the Schroedinger equation for charged Bosons and Fermions was used to calculate the correlation energies, to locate the transitions to their respective crystal phases at zero temperature within 10%, and to establish the stability at intermediate densities of a ferromagnetic fluid of electrons

  20. State and Trait Effects on Individual Differences in Children's Mathematical Development

    Science.gov (United States)

    Bailey, Drew H.; Watts, Tyler W.; Littlefield, Andrew K.; Geary, David C.

    2015-01-01

    Substantial longitudinal relations between children's early mathematics achievement and their much later mathematics achievement are firmly established. These findings are seemingly at odds with studies showing that early educational interventions have diminishing effects on children's mathematics achievement across time. We hypothesized that individual differences in children's later mathematical knowledge are more an indicator of stable, underlying characteristics related to mathematics learning throughout development than of direct effects of early mathematical competency on later mathematical competency. We tested this hypothesis in two longitudinal data sets, by simultaneously modeling effects of latent traits (stable characteristics that influence learning across time) and states (e.g., prior knowledge) on children's mathematics achievement over time. Latent trait effects on children's mathematical development were substantially larger than state effects. Approximately 60% of the variance in trait mathematics achievement was accounted for by commonly used control variables, such as working memory, but residual trait effects remained larger than state effects. Implications for research and practice are discussed. PMID:25231900

  1. Detection of water and its derivatives on individual nanoparticles using vibrational electron energy-loss spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Crozier, Peter A., E-mail: crozier@asu.edu [School for the Engineering of Matter, Transport and Energy, Arizona State University, 501 E. Tyler Mall, Tempe, AZ 85287-6106 (United States); Aoki, Toshihiro [LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, AZ 85287-1704 (United States); Liu, Qianlang [School for the Engineering of Matter, Transport and Energy, Arizona State University, 501 E. Tyler Mall, Tempe, AZ 85287-6106 (United States)

    2016-10-15

    Understanding the role of water, hydrate and hydroxyl species on nanoparticle surfaces and interfaces is very important in both physical and life sciences. Detecting the presence of oxygen-hydrogen species with nanometer resolution is extremely challenging at present. Here we show that the recently developed vibrational electron energy-loss spectroscopy using subnanometer focused electron beams can be employed to spectroscopically identify the local presence and variation of OH species on nanoscale surfaces. The hydrogen-oxygen fingerprint can be correlated with highly localized structural and morphological information obtained from electron imaging. Moreover, the current approach exploits the aloof beam mode of spectral acquisition which does not require direct electron irradiation of the sample thus greatly reducing beam damage to the OH bond. These findings open the door for using electron microscopy to probe local hydroxyl and hydrate species on nanoscale organic and inorganic structures. - Highlights: • High spatial resolution spectroscopic detection of water related species in nanoparticles. • Detection of OH stretch modes with vibrational EELS. • Differentiation between hydrate and hydroxide species on or on nanoparticles. • Detection of hydrate on a single 60 nm oxide nanoparticle of MgO. • Use of aloof beam EELS to minimize radiation damage.

  2. Individual monitoring with official electronic dosemeters in Germany - concepts and reality

    International Nuclear Information System (INIS)

    Martini, E.; Wahl, W.; Huebner, S.; Freynhagen, D.; Staemmler, M.

    2005-01-01

    Full text: Active (electronic) personal dosemeters (APD) are radiometers, which are equipped as active or passive dosimeters. They can directly indicate a dose rate and/or the dose integrated during a certain period (direct-indicating, active electronic personal dosemeters mentioned) or only over a separate reader (direct-selectable, passive electronic personal dosemeters mentioned). A concept is presented for the use of passive or active electronic personal dosemeters in Germany as official dosemeters, e.g. in hospitals. The concept features a net-based approach for secure data communication between readers for passive and active electronic personal dosemeters und the official personal dosimetry monitoring service(s), taking the German policies (StrISchV und RoeV in hospitals) into account. The net-based solution includes a processor controlled interface via TCP/IP connected to the dosimetry reader(s), und reader interfaces, an official interim data bank and all the necessary equipment such as PC, Raid-configuration, USV support, network connection and further details. Investigations have been started to achieve highest-level data manipulation security, data completeness und data correctness. (author)

  3. Two-state model of excess electron relaxation and geminate recombination in water and aqueous solutions

    International Nuclear Information System (INIS)

    Fedorenko, S.G.

    2010-01-01

    Graphical abstract: After photo-induced ionization a free electron suffers a quick conversion to a solvated state, and then recombines with the parent atom or ion. However, high mobility and reactivity of a free electron can allow the electron to delocalize and recombine in the free state. The theory of two channel processes of geminate electron recombination is developed and applied to the experiment of three-pulse generation of excess electrons in water. - Abstract: After photo-induced ionization a free electron suffers a quick conversion to a solvated state, and then can recombine with the parent atom or ion. However, high mobility and reactivity of a free electron can allow the electron to delocalize and recombine in the free state. The theory of two channel processes of geminate electron recombination is developed here for the general type of the Markovian motion of reactants. A contact model is used for analytical solution of the problem of geminate recombination of neutral and charged reactants. The theory is applied to the experiment of three-pulse generation of excess electrons in water.

  4. Tuning of few-electron states and optical absorption anisotropy in GaAs quantum rings.

    Science.gov (United States)

    Wu, Zhenhua; Li, Jian; Li, Jun; Yin, Huaxiang; Liu, Yu

    2017-11-15

    The electronic and optical properties of a GaAs quantum ring (QR) with few electrons in the presence of the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI) have been investigated theoretically. The configuration interaction (CI) method is employed to calculate the eigenvalues and eigenstates of the multiple-electron QR accurately. Our numerical results demonstrate that the symmetry breaking induced by the RSOI and DSOI leads to an anisotropic distribution of multi-electron states. The Coulomb interaction offers additional modulation of the electron distribution and thus the optical absorption indices in the quantum rings. By tuning the magnetic/electric fields and/or electron numbers in a quantum ring, one can change its optical properties significantly. Our theory provides a new way to control the multi-electron states and optical properties of a QR by hybrid modulations or by electrical means only.

  5. Quantum tunneling of electron snake states in an inhomogeneous magnetic field

    Science.gov (United States)

    Hoodbhoy, Pervez

    2018-05-01

    In a two dimensional free electron gas subjected to a perpendicular spatially varying magnetic field, the classical paths of electrons are snake-like trajectories that weave along the line where the field crosses zero. But quantum mechanically this system is described by a symmetric double well potential which, for low excitations, leads to very different electron behavior. We compute the spectrum, as well as the wavefunctions, for states of definite parity in the limit of nearly degenerate states, i.e. for electrons sufficiently far from the B z   =  0 line. Transitions between the states are shown to give rise to a tunneling current. If the well is made asymmetrical by a time-dependent parity breaking perturbation then Rabi-like oscillations between parity states occur. Resonances can be excited and used to stimulate the transfer of electrons from one side of the potential barrier to the other through quantum tunneling.

  6. Quantum tunneling of electron snake states in an inhomogeneous magnetic field.

    Science.gov (United States)

    Hoodbhoy, Pervez

    2018-05-10

    In a two dimensional free electron gas subjected to a perpendicular spatially varying magnetic field, the classical paths of electrons are snake-like trajectories that weave along the line where the field crosses zero. But quantum mechanically this system is described by a symmetric double well potential which, for low excitations, leads to very different electron behavior. We compute the spectrum, as well as the wavefunctions, for states of definite parity in the limit of nearly degenerate states, i.e. for electrons sufficiently far from the B z   =  0 line. Transitions between the states are shown to give rise to a tunneling current. If the well is made asymmetrical by a time-dependent parity breaking perturbation then Rabi-like oscillations between parity states occur. Resonances can be excited and used to stimulate the transfer of electrons from one side of the potential barrier to the other through quantum tunneling.

  7. Construction of an individual trajectory of learning computer science using an electronic database of educational material

    Directory of Open Access Journals (Sweden)

    Алексей Андреевич Заславский

    2010-09-01

    Full Text Available In this paper the approach for the use of automated information system directly in the classroom to form a personal set of tasks for a particular student and build individual trajectory of its development.

  8. Electron impact excitation of autoionising states of krypton

    Science.gov (United States)

    Srivastava, S. K.; Trajmar, S.

    1978-01-01

    Energy-loss spectra of krypton in the region between 21 and 29 eV have been obtained at electron impact energies of 30, 60 and 100 eV. For each energy, the angular distribution of intensities has been measured at 5, 10 and 15 deg scattering angles. Assignments of spectral features found in this region are suggested and a comparison is made with previous measurements.

  9. 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.

  10. Mental Health Correlates of Cigarette Use in LGBT Individuals in the Southeastern United States.

    Science.gov (United States)

    Drescher, Christopher F; Lopez, Eliot J; Griffin, James A; Toomey, Thomas M; Eldridge, Elizabeth D; Stepleman, Lara M

    2018-05-12

    Smoking prevalence for lesbian, gay, bisexual, and transgender (LGBT) individuals is higher than for heterosexual, cisgender individuals. Elevated smoking rates have been linked to psychiatric comorbidities, substance use, poverty, low education levels, and stress. This study examined mental health (MH) correlates of cigarette use in LGBT individuals residing in a metropolitan area in the southeastern United States. Participants were 335 individuals from an LGBT health needs assessment (mean age 34.7; SD = 13.5; 63% gay/lesbian; 66% Caucasian; 81% cisgender). Demographics, current/past psychiatric diagnoses, number of poor MH days in the last 30, the Patient Health Questionnaire (PHQ) 2 depression screener, the Three-Item Loneliness Scale, and frequency of cigarette use were included. Analyses included bivariate correlations, analysis of variance (ANOVA), and regression. Multiple demographic and MH factors were associated with smoker status and frequency of smoking. A logistic regression indicated that lower education and bipolar disorder were most strongly associated with being a smoker. For smokers, a hierarchical regression model including demographic and MH variables accounted for 17.6% of the variance in frequency of cigarette use. Only education, bipolar disorder, and the number of poor MH days were significant contributors in the overall model. Conclusions/Importance: Less education, bipolar disorder, and recurrent poor MH increase LGBT vulnerability to cigarette use. Access to LGBT-competent MH providers who can address culturally specific factors in tobacco cessation is crucial to reducing this health disparities.

  11. Two-state Markov-chain Poisson nature of individual cellphone call statistics

    Science.gov (United States)

    Jiang, Zhi-Qiang; Xie, Wen-Jie; Li, Ming-Xia; Zhou, Wei-Xing; Sornette, Didier

    2016-07-01

    Unfolding the burst patterns in human activities and social interactions is a very important issue especially for understanding the spreading of disease and information and the formation of groups and organizations. Here, we conduct an in-depth study of the temporal patterns of cellphone conversation activities of 73 339 anonymous cellphone users, whose inter-call durations are Weibull distributed. We find that the individual call events exhibit a pattern of bursts, that high activity periods are alternated with low activity periods. In both periods, the number of calls are exponentially distributed for individuals, but power-law distributed for the population. Together with the exponential distributions of inter-call durations within bursts and of the intervals between consecutive bursts, we demonstrate that the individual call activities are driven by two independent Poisson processes, which can be combined within a minimal model in terms of a two-state first-order Markov chain, giving significant fits for nearly half of the individuals. By measuring directly the distributions of call rates across the population, which exhibit power-law tails, we purport the existence of power-law distributions, via the ‘superposition of distributions’ mechanism. Our findings shed light on the origins of bursty patterns in other human activities.

  12. The impact and implications of undocumented immigration on individual and collective health in the United States.

    Science.gov (United States)

    Hilfinger Messias, DeAnne K; McEwen, Marylyn Morris; Clark, Lauren

    2015-01-01

    A nation of immigrants, the United States currently has more foreign-born residents than any other country; approximately 28% of these foreign-born residents are undocumented immigrants--individuals who either entered or are currently residing in the country without valid immigration or residency documents. The complex and constantly changing social, political, and economic context of undocumented migration has profound effects on individuals, families, and communities. The lack of demographic and epidemiologic data on undocumented immigrants is a major public health challenge. In this article, we identify multiple dimensions of vulnerability among undocumented persons; examine how undocumentedness impacts health and health care access and utilization; and consider the professional, practice, and policy issues and implications for nurses. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    CERN Document Server

    Gumberidze, A; Barnás, D; Beckert, Karl; Beller, Peter; Beyer, H F; Bosch, F; Cai, X; Stöhlker, T; Hagmann, S; Kozhuharov, C; Liesen, D; Nolden, F; Ma, X; Mokler, P H; Orsic-Muthig, A; Steck, Markus; Sierpowski, D; Tashenov, S; Warczak, A; Zou, Y

    2004-01-01

    Radiative recombination transitions into the ground state of cooled bare and hydrogen-like 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.

  14. Income inequality and mortality: a multilevel prospective study of 521 248 individuals in 50 US states.

    Science.gov (United States)

    Backlund, Eric; Rowe, Geoff; Lynch, John; Wolfson, Michael C; Kaplan, George A; Sorlie, Paul D

    2007-06-01

    Some of the most consistent evidence in favour of an association between income inequality and health has been among US states. However, in multilevel studies of mortality, only two out of five studies have reported a positive relationship with income inequality after adjustment for the compositional characteristics of the state's inhabitants. In this study, we attempt to clarify these mixed results by analysing the relationship within age-sex groups and by applying a previously unused analytical method to a database that contains more deaths than any multilevel study to date. The US National Longitudinal Mortality Study (NLMS) was used to model the relationship between income inequality in US states and mortality using both a novel and previously used methodologies that fall into the general framework of multilevel regression. We adjust age-sex specific models for nine socioeconomic and demographic variables at the individual level and percentage black and region at the state level. The preponderance of evidence from this study suggests that 1990 state-level income inequality is associated with a 40% differential in state level mortality rates (95% CI = 26-56%) for men 25-64 years and a 14% (95% CI = 3-27%) differential for women 25-64 years after adjustment for compositional factors. No such relationship was found for men or women over 65. The relationship between income inequality and mortality is only robust to adjustment for compositional factors in men and women under 65. This explains why income inequality is not a major driver of mortality trends in the United States because most deaths occur at ages 65 and over. This analysis does suggest, however, the certain causes of death that occur primarily in the population under 65 may be associated with income inequality. Comparison of analytical techniques also suggests coefficients for income inequality in previous multilevel mortality studies may be biased, but further research is needed to provide a definitive

  15. ELECTRONIC PROFESSIONAL EDITIONS IN THE SYSTEM OF SCIENTIFIC PERIODICALS: STATE AND PROSPECTS

    Directory of Open Access Journals (Sweden)

    Nataliia M. Kropocheva

    2014-02-01

    Full Text Available The article highlights relevant current problems concerning the formation, present state and prospects of the development of the native electronic professional editions on pedagogy. The historical overview of the development of the electronic books in the world and in Ukraine in general, and also including the professional editions was made. It was conducted the analysis of national and international legal framework for existing electronic editions, as well as researched the structure and software of the native electronic professional editions on pedagogy. Based on the results, it was formulated the conclusions and developed some suggestions for the improvement of electronic editions.

  16. Resting-state low-frequency fluctuations reflect individual differences in spoken language learning

    Science.gov (United States)

    Deng, Zhizhou; Chandrasekaran, Bharath; Wang, Suiping; Wong, Patrick C.M.

    2016-01-01

    A major challenge in language learning studies is to identify objective, pre-training predictors of success. Variation in the low-frequency fluctuations (LFFs) of spontaneous brain activity measured by resting-state functional magnetic resonance imaging (RS-fMRI) has been found to reflect individual differences in cognitive measures. In the present study, we aimed to investigate the extent to which initial spontaneous brain activity is related to individual differences in spoken language learning. We acquired RS-fMRI data and subsequently trained participants on a sound-to-word learning paradigm in which they learned to use foreign pitch patterns (from Mandarin Chinese) to signal word meaning. We performed amplitude of spontaneous low-frequency fluctuation (ALFF) analysis, graph theory-based analysis, and independent component analysis (ICA) to identify functional components of the LFFs in the resting-state. First, we examined the ALFF as a regional measure and showed that regional ALFFs in the left superior temporal gyrus were positively correlated with learning performance, whereas ALFFs in the default mode network (DMN) regions were negatively correlated with learning performance. Furthermore, the graph theory-based analysis indicated that the degree and local efficiency of the left superior temporal gyrus were positively correlated with learning performance. Finally, the default mode network and several task-positive resting-state networks (RSNs) were identified via the ICA. The “competition” (i.e., negative correlation) between the DMN and the dorsal attention network was negatively correlated with learning performance. Our results demonstrate that a) spontaneous brain activity can predict future language learning outcome without prior hypotheses (e.g., selection of regions of interest – ROIs) and b) both regional dynamics and network-level interactions in the resting brain can account for individual differences in future spoken language learning success

  17. Resting-state low-frequency fluctuations reflect individual differences in spoken language learning.

    Science.gov (United States)

    Deng, Zhizhou; Chandrasekaran, Bharath; Wang, Suiping; Wong, Patrick C M

    2016-03-01

    A major challenge in language learning studies is to identify objective, pre-training predictors of success. Variation in the low-frequency fluctuations (LFFs) of spontaneous brain activity measured by resting-state functional magnetic resonance imaging (RS-fMRI) has been found to reflect individual differences in cognitive measures. In the present study, we aimed to investigate the extent to which initial spontaneous brain activity is related to individual differences in spoken language learning. We acquired RS-fMRI data and subsequently trained participants on a sound-to-word learning paradigm in which they learned to use foreign pitch patterns (from Mandarin Chinese) to signal word meaning. We performed amplitude of spontaneous low-frequency fluctuation (ALFF) analysis, graph theory-based analysis, and independent component analysis (ICA) to identify functional components of the LFFs in the resting-state. First, we examined the ALFF as a regional measure and showed that regional ALFFs in the left superior temporal gyrus were positively correlated with learning performance, whereas ALFFs in the default mode network (DMN) regions were negatively correlated with learning performance. Furthermore, the graph theory-based analysis indicated that the degree and local efficiency of the left superior temporal gyrus were positively correlated with learning performance. Finally, the default mode network and several task-positive resting-state networks (RSNs) were identified via the ICA. The "competition" (i.e., negative correlation) between the DMN and the dorsal attention network was negatively correlated with learning performance. Our results demonstrate that a) spontaneous brain activity can predict future language learning outcome without prior hypotheses (e.g., selection of regions of interest--ROIs) and b) both regional dynamics and network-level interactions in the resting brain can account for individual differences in future spoken language learning success

  18. A completely CAD/CAM individual transmission device for electronic mandible movement registration.

    Science.gov (United States)

    Krey, Karl-Friedrich; Kordaß, Bernd; Ruge, Sebastian

    The connection of a device for the registration of mandibular movements depends on the coupling of the teeth with a paraocclusal adapter. This is normally done by individualizing a prefabricated metal support, either directly on the patient or in the dental laboratory. The goal was to create an individual paraocclusal adapter by means of additive computer-assisted design/computer-assisted manufacturing (CAD/CAM) procedures, and to test it clinically. Starting from intraoral scans of the maxillary and mandibular teeth, an individual paraocclusal adapter was constructed by combining an adapter piece adapted to the tooth and jaw shape with a prefabricated standard part. This article describes step by step the design using the 3D CAD software, up until production by means of 3D printing. Initial clinical experience is also discussed.

  19. Comparison of visual and electronic devices for individual identification of dromedary camels under different farming conditions.

    Science.gov (United States)

    Caja, G; Díaz-Medina, E; Salama, A A K; Salama, O A E; El-Shafie, M H; El-Metwaly, H A; Ayadi, M; Aljumaah, R S; Alshaikh, M A; Yahyahoui, M H; Seddik, M M; Hammadi, M; Khorchani, T; Amann, O; Cabrera, S

    2016-08-01

    The camel industry uses traditional (i.e., iron brands and ear tags) and modern (i.e., microchips) identification (ID) systems without having performance results of reference. Previously iron-branded ( = 45; 1 yr) and microchipped ( = 59; 7 yr) camels showed problems of healing (8.6% of brands) and reading (only 42.9% of brands and 69.5% of microchips were readable), which made their use inadvisable. With the aim of proposing suitable ID systems for different farming conditions, an on-field study was performed using a total of 528 dromedaries at 4 different locations (Egypt, = 83; Spain, = 304; Saudi Arabia, = 90; and Tunisia, = 51). The ID devices tested were visual (button ear tags, 28.5 mm diameter, = 178; double flag ear tags, 50 by 15 mm, = 83; both made of polyurethane) and electronic (ear tags, = 90, and rumen boluses, = 555). Electronic ear tags were polyurethane-loop type (75 by 9 mm) with a container in which a 22-mm transponder of full-duplex technology was lodged. Electronic boluses of 7 types, varying in dimensions (50 to 76 mm length, 11 to 21 mm width, and 12.7 to 82.1 g weight) and specific gravity (SG; 1.49 to 3.86) and each of them containing a 31-mm transponder of half-duplex technology, were all administered to the dromedaries at the beginning of the study. When a low-SG bolus was lost, a high-SG bolus was readministered. Readability rates of each ID system were evaluated during 1 to 3 yr, according to device and location, and yearly values were estimated for comparison. On a yearly basis, visual ear tag readability was not fully satisfactory; it was lower for rectangular ear tags (66.3%) than for button ear tags (80.9%). Yearly readability of electronic ear tags was 93.7%. Bolus readability dramatically varied according to their SG; the SG 3.0 boluses were efficiently retained (99.6 to 100%) at all locations. In conclusion, according to the expected long lifespan of camels, low ID performances were observed for iron brands, injectable

  20. State of the art of High Temperature Power Electronics

    OpenAIRE

    Buttay , Cyril; Planson , Dominique; Allard , Bruno; Bergogne , Dominique; Bevilacqua , Pascal; Joubert , Charles; Lazar , Mihai; Martin , Christian; Morel , Hervé; Tournier , Dominique; Raynaud , Christophe

    2009-01-01

    International audience; High temperature power electronics has become possible with the recent availability of silicon carbide devices. This material, as other wide-bandgap semiconductors, can operate at temperatures above 500°C, whereas silicon is limited to 150-200°C. Applications such as transportation or deep oil and gas wells drilling can benefit. A few converters operating above 200°C have been demonstrated, but work is still ongoing to design and build a power system able to operate in...

  1. On genealogy of defect electron states in semiconductor materials

    International Nuclear Information System (INIS)

    Makhmudov, A.Sh.

    1984-01-01

    Main factors of formation of defect electron structure in semiconductors are considered. It is concluded on the basis of analysis of papers published earlier that it is necessary to take account of two factors: long- and short-range orders i.e. the nature of the atom interaction with the several nearest neighbours as well as crystal periodicity, correctly formulated boundary conditions. One of possible wayes of the given task realization is the combination of a traditional scheme of the solid body theory- the Green function method and the semiempirical quantum-chemical method of equivalent orbitales

  2. Electronic States and Persistent Currents in Nanowire Quantum Ring

    Science.gov (United States)

    Kokurin, I. A.

    2018-04-01

    The new model of a quantum ring (QR) defined inside a nanowire (NW) is proposed. The one-particle Hamiltonian for electron in [111]-oriented NW QR is constructed taking into account both Rashba and Dresselhaus spin-orbit coupling (SOC). The energy levels as a function of magnetic field are found using the exact numerical diagonalization. The persistent currents (both charge and spin) are calculated. The specificity of SOC and arising anticrossings in energy spectrum lead to unusual features in persistent current behavior. The variation of magnetic field or carrier concentration by means of gate can lead to pure spin persistent current with the charge current being zero.

  3. The diffusion of electronic business in the United States

    OpenAIRE

    Emin M. Dinlersoz; Rubén Hernández-Murillo

    2005-01-01

    The authors provide a recent account of the diffusion of electronic business in the U.S. economy using new data from the U.S. Bureau of the Census. They document the extent of the diffusion in three main sectors of the economy: retail, services, and manufacturing. For manufacturing, they also analyze plants' patterns of adoption of several Internet-based processes and conclude with a look at the future of the Internet's diffusion and a prospect for further data collection by the U.S. Census B...

  4. Electronic-state control of amino acids on semiconductor surfaces

    International Nuclear Information System (INIS)

    Oda, Masato; Nakayama, Takashi

    2005-01-01

    Electronic structures of amino acids on the Si(1 1 1) surfaces are investigated by using ab initio Hartree-Fock calculations. It is shown that among various polar amino acids, a histidine is the only one that can be positively ionized when hole carriers are supplied in the Si substrate, by transferring the hole charge from Si substrate to an amino acid. This result indicates that the ionization of a histidine, which will activate the protein functions, can be controlled electrically by producing amino acid/Si junctions

  5. Empty-electronic-state evolution for Sc and electron dynamics at the 3p-3d giant dipole resonance

    International Nuclear Information System (INIS)

    Hu, Y.; Wagener, T.J.; Gao, Y.; Weaver, J.H.

    1989-01-01

    Inverse photoemission has been used to study the developing electronic states of an early transition metal, Sc, during thin-film growth and to investigate the effects of these states on the 3p-3d giant dipole resonance. Energy- and coverage-dependent intensity variations of the empty Sc states show that the 3d maximum moves 1.1 eV toward the Fermi level as the thickness of the Sc film increases from 1 to 300 A as measured with an incident electron energy of 41.25 eV, an effect attributed to metallic band formation via hybridization of atomic 4s and 3d states. Incident-energy-dependent intensity variations for these empty Sc features show resonant photon emission for incident electron energies above the 3p threshold, with maxima at 43 and 44 eV for 300- and 5-A-thick films, respectively. Considerations of hybridization-induced energy shifts of the empty Sc 3d states demonstrate that the radiative energy changes very little with Sc coverages. These studies indicate coupling of decay channels involving the inverse photoemission continuum and the recombination of the atomic 3p-3d giant dipole transition, the energy of the latter being determined by atomic 3p-3d excitation processes

  6. 42 CFR 435.230 - Aged, blind, and disabled individuals in States that use more restrictive requirements for...

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Aged, blind, and disabled individuals in States... Coverage of the Aged, Blind, and Disabled § 435.230 Aged, blind, and disabled individuals in States that... for aged, blind, and disabled SSI recipients using more restrictive requirements than those used under...

  7. Critical Electronic Data Loss Perceptions of United States Military Contractors

    Science.gov (United States)

    Singletary, Tod J.

    2017-01-01

    The United States Military has become increasingly dependent upon technology to meet its mission objectives with a consequence being greater dependence on civilian defense contractors to provide specialized services in support of high-tech mission requirements. Modern military defense contractors have also become dependent upon reliable and secure…

  8. Electronic Timekeeping: North Dakota State University Improves Payroll Processing.

    Science.gov (United States)

    Vetter, Ronald J.; And Others

    1993-01-01

    North Dakota State University has adopted automated timekeeping to improve the efficiency and effectiveness of payroll processing. The microcomputer-based system accurately records and computes employee time, tracks labor distribution, accommodates complex labor policies and company pay practices, provides automatic data processing and reporting,…

  9. Anisotropy of electronic states excited in ion-atom collisions

    International Nuclear Information System (INIS)

    Boskamp, E.B.

    1983-01-01

    The author reports coincidence measurements made on the He + + Ne and He + + He systems. The complex population amplitudes for the magnetic sublevels of the investigated excited states, Ne(2p 4 3s 2 ) 1 D and He(2p 2 ) 1 D, were completely determined and possible excitation mechanisms are described. (Auth.)

  10. Development of an electronic monitor for the determination of individual radon and thoron exposure

    Energy Technology Data Exchange (ETDEWEB)

    Irlinger, Josef

    2015-06-11

    The carcinogenic effect of the radio isotope {sup 222}Rn of the noble gas radon and its progeny, as well as its residential distribution, are well studied. In contrast, the knowledge about the effects and average dwelling concentration levels of its radio isotope {sup 220}Rn (thoron) is still limited. Generally, this isotope has been assumed to be a negligible contributor to the effective annual dose. However, only recently it has been pointed out in several international studies, that the dose due to thoron exceeds the one from {sup 222}Rn under certain conditions. Additionally, radon monitors may show a considerable sensitivity towards thoron which was also not accounted for in general. Therefore a reliable, inexpensive exposimeter, which allows to distinguish between decays of either radon and thoron, is required to conduct further studies. The scope of this thesis was to develop an electronic radon/thoron exposimeter which features small size, low weight and minimal power consumption. The design is based on the diffusion chamber principle and employs state-of-the-art alpha particle spectroscopy to measure activity concentrations. The device was optimized via inlet layout and filter selection for high thoron diffusion. Calibration measurements showed a similar sensitivity of the monitor towards radon and thoron, with a calibration factor of cf{sup {sub 2}{sub 2}{sub 2Rn}} = 16.2 ± 0.9 Bq m{sup -3}/cph and cf{sup {sub 2}{sub 2}{sub 0Rn}} = 14.4 ± 0.8 Bq m{sup -3}/cph, respectively. Thus, the radon sensitivity of the device was enhanced by a factor two compared to a previous prototype. The evaluation method developed in this work, in accordance with ISO 11665 standards, was validated by intercomparison measurements. The detection limits for radon and thoron were determined to be C{sup {sub 2}{sub 2}{sub 2Rn}} = 44.0 Bq m{sup -3} and C{sup {sub 2}{sub 2}{sub 0Rn}} = 40.0 Bq m{sup -3}, respectively, in case of a low radon environment, a one-hour measurement

  11. Development of an electronic monitor for the determination of individual radon and thoron exposure

    International Nuclear Information System (INIS)

    Irlinger, Josef

    2015-01-01

    The carcinogenic effect of the radio isotope 222 Rn of the noble gas radon and its progeny, as well as its residential distribution, are well studied. In contrast, the knowledge about the effects and average dwelling concentration levels of its radio isotope 220 Rn (thoron) is still limited. Generally, this isotope has been assumed to be a negligible contributor to the effective annual dose. However, only recently it has been pointed out in several international studies, that the dose due to thoron exceeds the one from 222 Rn under certain conditions. Additionally, radon monitors may show a considerable sensitivity towards thoron which was also not accounted for in general. Therefore a reliable, inexpensive exposimeter, which allows to distinguish between decays of either radon and thoron, is required to conduct further studies. The scope of this thesis was to develop an electronic radon/thoron exposimeter which features small size, low weight and minimal power consumption. The design is based on the diffusion chamber principle and employs state-of-the-art alpha particle spectroscopy to measure activity concentrations. The device was optimized via inlet layout and filter selection for high thoron diffusion. Calibration measurements showed a similar sensitivity of the monitor towards radon and thoron, with a calibration factor of cf 222 Rn = 16.2 ± 0.9 Bq m -3 /cph and cf 220 Rn = 14.4 ± 0.8 Bq m -3 /cph, respectively. Thus, the radon sensitivity of the device was enhanced by a factor two compared to a previous prototype. The evaluation method developed in this work, in accordance with ISO 11665 standards, was validated by intercomparison measurements. The detection limits for radon and thoron were determined to be C 2 22 Rn = 44.0 Bq m -3 and C 2 20 Rn = 40.0 Bq m -3 , respectively, in case of a low radon environment, a one-hour measurement interval, and a background count rate of zero. In contrast, in mixed radon/thoron concentrations where the 212 Po peak must

  12. Creation of paired electron states in the gap of semiconducting carbon nanotubes by correlated hydrogen adsorption

    International Nuclear Information System (INIS)

    Buchs, Gilles; Krasheninnikov, Arkady V; Ruffieux, Pascal; Groening, Pierangelo; Foster, Adam S; Nieminen, Risto M; Groening, Oliver

    2007-01-01

    The specific, local modification of the electronic structure of carbon nanomaterials is as important for novel electronic device fabrication as the doping in the case of silicon-based electronics. Here, we report low temperature scanning tunneling microscopy and spectroscopy study of semiconducting carbon nanotubes subjected to hydrogen-plasma treatment. We show that plasma treatment mostly results in the creation of paired electronic states in the nanotube band gap. Combined with extensive first-principle simulations, our results provide direct evidence that these states originate from correlated chemisorption of hydrogen adatoms on the tube surface. The energy splitting of the paired states is governed by the adatom-adatom interaction, so that controlled hydrogenation can be used for engineering the local electronic structure of nanotubes and other sp 2 -bonded nanocarbon systems

  13. Experimental efforts at NIST towards one-electron ions in circular Rydberg states

    International Nuclear Information System (INIS)

    Tan, Joseph N; Guise, Nicholas D; Brewer, Samuel M

    2011-01-01

    Experimental effort is underway at NIST to enable tests of theory with one-electron ions synthesized in circular Rydberg states from captured bare nuclei. Problematic effects that limit the accuracy of predicted energy levels for low-lying states are vanishingly small for high-angular-momentum (high-L) states; in particular, the nuclear size correction for high-L states is completely negligible for any foreseeable improvement of measurement precision. As an initial step towards realizing such states, highly charged ions are extracted from the NIST electron beam ion trap (EBIT) and steered through the electrodes of a Penning trap. The goal is to capture bare nuclei in the Penning trap for experiments to make one-electron atoms in circular Rydberg states with dipole (E1) transitions in the optical domain accessible to a frequency comb.

  14. Final state interactions in electron induced trinucleon breakup reactions

    International Nuclear Information System (INIS)

    Meijgaard, E. van.

    1989-01-01

    This thesis presents an exact analysis of the electromagnetic breakup process of a trinucleon system. The one-photon exchange mechanism is reviewed. The relevant components of the nuclear current are discussed and the off-shell one-body current matrix elements are derived to accommodate the evaluation of the trinucleon nuclear structure functions. The Faddeev equations are introduced. To facilitate the numerical evaluations the unitary pole expansion (UPE) is employed to describe a local S-wave spin-dependent interaction in a series of separable potential terms. The UPE convergence properties for the trinucleon bound state as well as for the N-N and N-d scattering observables are investigated. In view of the electromagnetic two-body and three-body breakup analysis the half off-shell wave functions for 3N→Nd and 3N→3N scattering are calculated. The nuclear structure functions of the electromagnetic two-body breakup structure functions of the electromagnetic two-body breakup processes are derived and exactly calculated. Results are presented and discussed for several kinetamic configurations. The nuclear response functions of the trinucleon breakup processes are calculated for a momentum transfer Q = 400 MeV/c. The results are compared with recent experimental data for the longitudinal and transverse response of both trinucleon systems. The three-body contributions to the response functions result from an essentially fourfold numerical integration of the invariant electromagnetic three-body breakup amplitude. A detailed derivation of this amplitude is presented and the treatment of the subsequent integration is discussed. An extension is formulated to include D-state components in the trinucleon bound state as well as in the disconnected final state components for the two-body breakup process. One kinematic situation is studied with the D-state extension. For the three-body breakup processes only the PWIA response is determined with the D-state component in the

  15. Electron spin exchange of shallow donor muonium states

    International Nuclear Information System (INIS)

    Senba, Masayoshi

    2005-01-01

    Shallow donor muonium states with small hyperfine frequencies, recently observed in II-VI semiconductor compounds, have a number of unique features that present both opportunities and challenges in understanding muon spin dynamics in the presence of Heisenberg spin exchange. First, the shallow muonium state in CdSe with hyperfine frequency ω 0 /2π ∼ 0.1 MHz is already in the high field regime even in the earth's magnetic field, where only two precession frequencies are observable by the muon spin rotation (μSR) technique. Second, unlike in the case of more conventional muonium species with a larger hyperfine frequency, the μSR signal of shallow muonium states can be observed even in the transition region, between the slow spin-flip regime and the fast spin-flip regime, where the spin-flip rate and the hyperfine frequency are comparable. The muon spin dynamics in the transition region has not been theoretically explored previously, mainly because normal muonium in vacuum gives no observable signal in this region. Third, in the case of shallow muonium states, the incoherent process defined to be those spin-flip collisions that cause changes in muon spin precession frequencies, becomes crucially important in the transition region, where the incoherent process is entirely negligible in more conventional muonium species. By taking incoherent multiple collisions into account, an analytical expression for the time evolution of the muon spin polarization in Mu is derived, where Mu undergoes repeated spin-flip collisions. Comparisons with Monte Carlo calculations show that the analytical expression obtained in this work can reliably be used to analyse experimental data for shallow donor states not only in the slow spin-flip regime, but also in the transition region up to the onset of the fast regime. The present work confirms a recent experimental finding that, in the transition region, the initial phases of the two precession components of shallow donor states

  16. Dipole-resonance assisted isomerization in the electronic ground state using few-cycle infrared pulses.

    Science.gov (United States)

    Skocek, Oliver; Uiberacker, Christoph; Jakubetz, Werner

    2011-06-30

    A computational investigation of HCN → HNC isomerization in the electronic ground state by one- and few-cycle infrared pulses is presented. Starting from a vibrationally pre-excited reagent state, isomerization yields of more than 50% are obtained using single one- to five-cycle pulses. The principal mechanism includes two steps of population transfer by dipole-resonance (DR), and hence, the success of the method is closely linked to the polarity of the system and, in particular, the stepwise change of the dipole moment from reactant to transition state and on to products. The yield drops massively if the diagonal dipole matrix elements are artificially set to zero. In detail, the mechanism includes DR-induced preparation of a delocalized vibrational wavepacket, which traverses the barrier region and is finally trapped in the product well by DR-dominated de-excitation. The excitation and de-excitation steps are triggered by pulse lobes of opposite field direction. As the number of optical cycles is increased, the leading field lobes prepare a vibrational superposition state by off-resonant ladder climbing, which is then subjected to the three steps of the principal isomerization mechanism. DR excitation is more efficient from a preformed vibrational wavepacket than from a molecular eigenstate. The entire process can be loosely described as Tannor-Kosloff-Rice type transfer mechanism on a single potential surface effected by a single pulse, individual field lobes assuming the roles of pump- and dump-pulses. Pre-excitation to a transient wavepacket can be enhanced by applying a separate, comparatively weak few-cycle prepulse, in which the prepulse prepares a vibrational wavepacket. The two-pulse setup corresponds to a double Tannor-Kosloff-Rice control scheme on a single potential surface.

  17. [Electronic cigarette : state of the science about toxicological aspects].

    Science.gov (United States)

    Deville, M; Charlier, C

    2017-01-01

    Electronic cigarettes (e-cigarettes) are presented as a healthier alternative to tobacco smoking. They are designed to contain a solution which is heated to produce an aerosol inhaled by the user. The liquid is mainly composed of propylene glycol, glycerol, flavours and, in some cases, nicotine. Except for nicotine, which can be fatal when ingested at high dose, these components are generally considered as safe. However, the potential effect of long term exposure to inhaled propylene glycol is unknown at this time. As an advantage, toxic compounds responsible for the noxiousness of tobacco smoking (nitrosamines, metals, formaldehyde, carbon monoxide …) are either absent, or present in the smoke of e-cigarette at levels far less compared to conventional cigarette smoke. Finally, efficacy of e-cigarette as a tool for smoking cessation stays to be proven.

  18. Coupled state analysis of electron excitations in asymmetric collision systems

    International Nuclear Information System (INIS)

    Mehler, G.; Reus, T. de; Mueller, U.; Reinhardt, J.; Mueller, B.; Greiner, W.; Soff, G.

    1985-01-01

    A coupled channel formalism is presented, using relativistic basis states of the target atom. Screening effects are incorporated by means of an effective potential of Hartree-Fock-Slater type. Relativistic wave packets are employed for the description of the continuum. The impact parameter dependence of the K-hole production in p-Ag collisions is calculated, including quadrupole contributions of the projectile Coulomb potential. The results are compared with experimental data. (orig.)

  19. Electronic Democracy and Environmental Governance: A Survey of the States

    OpenAIRE

    Beierle, Thomas; Cahill, Sarah

    2000-01-01

    Just as information technology is rapidly changing how we work, shop, and play, it is changing how we practice democracy. This paper focuses on one area where the Internet is broadening public participation in governance: the administration of environmental laws and regulations. It describes a survey of how each of the 50 states is using the Internet to provide citizens with environmental information, gather public input on agency decisions, and foster networks of interested citizens. As "lab...

  20. Opto-electronic conversion logic behaviour through dynamic modulation of electron/energy transfer states at the TiO2-carbon quantum dot interface.

    Science.gov (United States)

    Wang, Fang; Zhang, Yonglai; Liu, Yang; Wang, Xuefeng; Shen, Mingrong; Lee, Shuit-Tong; Kang, Zhenhui

    2013-03-07

    Here we show a bias-mediated electron/energy transfer process at the CQDs-TiO(2) interface for the dynamic modulation of opto-electronic properties. Different energy and electron transfer states have been observed in the CQDs-TNTs system due to the up-conversion photoluminescence and the electron donation/acceptance properties of the CQDs decorated on TNTs.

  1. Constrained State Estimation for Individual Localization in Wireless Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Xiaoxue Feng

    2014-11-01

    Full Text Available Wireless body sensor networks based on ultra-wideband radio have recently received much research attention due to its wide applications in health-care, security, sports and entertainment. Accurate localization is a fundamental problem to realize the development of effective location-aware applications above. In this paper the problem of constrained state estimation for individual localization in wireless body sensor networks is addressed. Priori knowledge about geometry among the on-body nodes as additional constraint is incorporated into the traditional filtering system. The analytical expression of state estimation with linear constraint to exploit the additional information is derived. Furthermore, for nonlinear constraint, first-order and second-order linearizations via Taylor series expansion are proposed to transform the nonlinear constraint to the linear case. Examples between the first-order and second-order nonlinear constrained filters based on interacting multiple model extended kalman filter (IMM-EKF show that the second-order solution for higher order nonlinearity as present in this paper outperforms the first-order solution, and constrained IMM-EKF obtains superior estimation than IMM-EKF without constraint. Another brownian motion individual localization example also illustrates the effectiveness of constrained nonlinear iterative least square (NILS, which gets better filtering performance than NILS without constraint.

  2. Constrained State Estimation for Individual Localization in Wireless Body Sensor Networks

    Science.gov (United States)

    Feng, Xiaoxue; Snoussi, Hichem; Liang, Yan; Jiao, Lianmeng

    2014-01-01

    Wireless body sensor networks based on ultra-wideband radio have recently received much research attention due to its wide applications in health-care, security, sports and entertainment. Accurate localization is a fundamental problem to realize the development of effective location-aware applications above. In this paper the problem of constrained state estimation for individual localization in wireless body sensor networks is addressed. Priori knowledge about geometry among the on-body nodes as additional constraint is incorporated into the traditional filtering system. The analytical expression of state estimation with linear constraint to exploit the additional information is derived. Furthermore, for nonlinear constraint, first-order and second-order linearizations via Taylor series expansion are proposed to transform the nonlinear constraint to the linear case. Examples between the first-order and second-order nonlinear constrained filters based on interacting multiple model extended kalman filter (IMM-EKF) show that the second-order solution for higher order nonlinearity as present in this paper outperforms the first-order solution, and constrained IMM-EKF obtains superior estimation than IMM-EKF without constraint. Another brownian motion individual localization example also illustrates the effectiveness of constrained nonlinear iterative least square (NILS), which gets better filtering performance than NILS without constraint. PMID:25390408

  3. Different nutritional-state indicators of HIV-positive individuals undergoing antiretroviral therapy

    Directory of Open Access Journals (Sweden)

    J. Geraix

    2008-01-01

    Full Text Available This study aimed at learning about the nutritional profile of HIV-positive individuals undergoing antiretroviral therapy and at comparing the performance of nutritional-state indicators. A transversal study was performed on 94 patients attending the Tropical Diseases Outpatient Hospital of Botucatu Medical School (FMB - UNESP. The body mass index (BMI and the classification by Papini-Berto (PB were used to evaluate nutritional state, aiming at detecting malnutrition and obesity. The waist-to-hips ratio (W/HR and waist circumference (WC were adopted for identification of abdominal obesity and lipodystrophy. According to BMI, most of the individuals were eutrophic, followed by 30.9% overweight and 6.4% malnourished. By using the PB classification, the frequency of malnourished increased (22.3%. The analysis of the PB classification in relation to BMI indicated that the former presented high sensitivity and good specificity for malnutrition diagnosis, namely 100% and 83%, respectively. The prevalence of abdominal obesity was 7.44% according to WC, and a higher prevalence (38.3% was observed when taking W/HR into account. There was significant positive association between nutritional diagnosis according to PB and T CD4+ lymphocyte. The results support the use of PB classification for malnutrition detection as well as that of BMI and W/HR for overweight and fat redistribution.

  4. Constrained state estimation for individual localization in wireless body sensor networks.

    Science.gov (United States)

    Feng, Xiaoxue; Snoussi, Hichem; Liang, Yan; Jiao, Lianmeng

    2014-11-10

    Wireless body sensor networks based on ultra-wideband radio have recently received much research attention due to its wide applications in health-care, security, sports and entertainment. Accurate localization is a fundamental problem to realize the development of effective location-aware applications above. In this paper the problem of constrained state estimation for individual localization in wireless body sensor networks is addressed. Priori knowledge about geometry among the on-body nodes as additional constraint is incorporated into the traditional filtering system. The analytical expression of state estimation with linear constraint to exploit the additional information is derived. Furthermore, for nonlinear constraint, first-order and second-order linearizations via Taylor series expansion are proposed to transform the nonlinear constraint to the linear case. Examples between the first-order and second-order nonlinear constrained filters based on interacting multiple model extended kalman filter (IMM-EKF) show that the second-order solution for higher order nonlinearity as present in this paper outperforms the first-order solution, and constrained IMM-EKF obtains superior estimation than IMM-EKF without constraint. Another brownian motion individual localization example also illustrates the effectiveness of constrained nonlinear iterative least square (NILS), which gets better filtering performance than NILS without constraint.

  5. Multi-state systems with selective propagated failures and imperfect individual and group protections

    International Nuclear Information System (INIS)

    Levitin, Gregory; Xing Liudong; Ben-Haim, Hanoch; Da, Yuanshun

    2011-01-01

    The paper presents an algorithm for evaluating performance distribution of complex series–parallel multi-state systems with propagated failures and imperfect protections. The failure propagation can have a selective effect, which means that the failures originated from different system elements can cause failures of different subsets of elements. Individual elements or some disjoint groups of elements can be protected from propagation of failures originated outside the group. The protections can fail with given probabilities. The suggested algorithm is based on the universal generating function approach and a generalized reliability block diagram method. The performance distribution evaluation procedure is repeated for each combination of propagated failures and protection failures. Both an analytical example and a numerical example are provided to illustrate the suggested algorithm. - Highlights: ► Systems with propagated failures and imperfect protections are considered. ► Failures originated from different elements can affect different subsets of elements. ► Protections of individual elements or groups of elements can fail with given probabilities. ► An algorithm for evaluating multi-state system performance distribution is suggested.

  6. Present state and progress of industrial electron processing systems in Japan

    International Nuclear Information System (INIS)

    Sakamoto, I.; Mizusawa, K.

    1983-01-01

    A summary is given of the state of utilisation of electron processing systems in Japan, mainly for (1) cross-linking of wire and cable insulator, (2) heat shrinkable tube and sheet, (3) foamed polyethylene, and (4) curing of paint coats. Details are given of some of the electron processing systems. (U.K.)

  7. Investigation of the hadronic final state in electron-proton interactions at HERA

    International Nuclear Information System (INIS)

    Dake, A.

    1995-01-01

    The main subject of this thesis is the study of the hardronic final state in deep-inelastic electron-proton scattering. Theexperiment described in this thesis is performed with such a high resolution that the substructure of the proton is probed by the electron beam with a resolution of less than 10 -15 cm. (orig./HSI)

  8. Magnetic translation group and classification of states of an itinerant electron

    International Nuclear Information System (INIS)

    Wal, Andrzej

    2006-01-01

    We consider an itinerant electron on two-dimensional finite square lattice in a magneticfield. A magnetic translation group (MTG) for this system with the periodic Born- Karman conditions has been introduced. The irreducible representation of MTG is used for classification of energy levels of electron states for this model

  9. Investigation of the hadronic final state in electron-proton interactions at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Dake, A

    1995-09-18

    The main subject of this thesis is the study of the hardronic final state in deep-inelastic electron-proton scattering. Theexperiment described in this thesis is performed with such a high resolution that the substructure of the proton is probed by the electron beam with a resolution of less than 10{sup -15} cm. (orig./HSI).

  10. Measurement of single electron and nuclear spin states based on optically detected magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Gennady P [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Bishop, Alan R [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Chernobrod, Boris M [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hawley, Marilyn E [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Brown, Geoffrey W [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Tsifrinovich, Vladimir I [Polytechnic University, Brooklyn, NY 11201 (United States)

    2006-05-15

    A novel approach for measurement of single electron and nuclear spin states is suggested. Our approach is based on optically detected magnetic resonance in a nano-probe located at the apex of an AFM tip. The method provides single electron spin sensitivity with nano-scale spatial resolution.

  11. Measurement of single electron and nuclear spin states based on optically detected magnetic resonance

    International Nuclear Information System (INIS)

    Berman, Gennady P; Bishop, Alan R; Chernobrod, Boris M; Hawley, Marilyn E; Brown, Geoffrey W; Tsifrinovich, Vladimir I

    2006-01-01

    A novel approach for measurement of single electron and nuclear spin states is suggested. Our approach is based on optically detected magnetic resonance in a nano-probe located at the apex of an AFM tip. The method provides single electron spin sensitivity with nano-scale spatial resolution

  12. In situ transmission electron microscopy of individual carbon nanotetrahedron/ribbon structures in bending

    Energy Technology Data Exchange (ETDEWEB)

    Kohno, Hideo, E-mail: kohno.hideo@kochi-tech.ac.jp [School of Environmental Science and Engineering, Kochi University of Technology, Kami, Kochi 782-8502 (Japan); Masuda, Yusuke [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

    2015-05-11

    When the direction of flattening of a carbon nanotube changes during growth mediated by a metal nanoparticle, a carbon nanotetrahedron is formed in the middle of the carbon nanoribbon. We report the bending properties of the carbon nanotetrahedron/nanoribbon structure using a micro-manipulator system in a transmission electron microscope. In many cases, bending occurs at an edge of the carbon nanotetrahedron. No significant change is observed in the tetrahedron's shape during bending, and the bending is reversible and repeatable. Our results show that the carbon nanotetrahedron/nanoribbon structure has good durability against mechanical bending.

  13. Binding of two-electron metastable states in semiconductor quantum dots under a magnetic field

    Science.gov (United States)

    Garagiola, Mariano; Pont, Federico M.; Osenda, Omar

    2018-04-01

    Applying a strong enough magnetic field results in the binding of few-electron resonant states. The mechanism was proposed many years ago but its verification in laboratory conditions is far more recent. In this work we study the binding of two-electron resonant states. The electrons are confined in a cylindrical quantum dot which is embedded in a semiconductor wire. The geometry considered is similar to the one used in actual experimental setups. The low-energy two-electron spectrum is calculated numerically from an effective-mass approximation Hamiltonian modelling the system. Methods for binding threshold calculations in systems with one and two electrons are thoroughly studied; in particular, we use quantum information quantities to assess when the strong lateral confinement approximation can be used to obtain reliable low-energy spectra. For simplicity, only cases without bound states in the absence of an external field are considered. Under these conditions, the binding threshold for the one-electron case is given by the lowest Landau energy level. Moreover, the energy of the one-electron bounded resonance can be used to obtain the two-electron binding threshold. It is shown that for realistic values of the two-electron model parameters it is feasible to bind resonances with field strengths of a few tens of tesla.

  14. Coherent electron - hole state and femtosecond cooperative emission in bulk GaAs

    International Nuclear Information System (INIS)

    Vasil'ev, Petr P; Kan, H; Ohta, H; Hiruma, T

    2002-01-01

    The conditions for obtaining a collective coherent electron - hole state in semiconductors are discussed. The results of the experimental study of the regime of cooperative recombination of high-density electrons and holes (more than 3 x 10 18 cm -3 ) in bulk GaAs at room temperature are presented. It is shown that the collective pairing of electrons and holes and their condensation cause the formation of a short-living coherent electron - hole BCS-like state, which exhibits radiative recombination in the form of high-power femtosecond optical pulses. It is experimentally demonstrated that almost all of the electrons and holes available are condensed at the very bottoms of the bands and are at the cooperative state. The average lifetime of this state is measured to be of about 300 fs. The dependences of the order parameter (the energy gap of the spectrum of electrons and holes) and the Fermi energy of the coherent BCS state on the electron - hole concentration are obtained. (special issue devoted to the 80th anniversary of academician n g basov's birth)

  15. The effect of weather and its changes on emotional state - individual characteristics that make us vulnerable

    Science.gov (United States)

    Spasova, Z.

    2011-03-01

    Given the proven effects of weather on the human organism, an attempt to examine its effects on a psychological and emotional level has been made. Emotions affect the bio tone, working ability, and concentration; hence their significance in various domains of economic life such as health care, education, transportation, and tourism. The present pilot study was conducted in Sofia, Bulgaria over a period of eight months, using five psychological methods: Eysenck Personality Questionnaire, State-Trait Anxiety Inventory, Test for Self-assessment of the emotional state, Test for evaluation of moods and Test ''Self-confidence-Activity-Mood''. The Fiodorov-Chubukov's complex-climatic method was used to characterize meteorological conditions in order to include a maximal number of meteorological elements in the analysis. Sixteen weather types are defined depending on the meteorological elements values according to this method. Abrupt weather changes from one day to another, defined by the same method, were also considered. The results obtained by t-test showed that the different categories of weather led to changes in the emotional status, which indicates a character either positive or negative for the organism. The abrupt weather changes, according to expectations, have negative effects on human emotions - but only when a transition to the cloudy weather or weather type, classified as ''unfavorable'', has been realized. The relationship between weather and human emotions is rather complicated since it depends on individual characteristics of people. One of these individual psychological characteristics, marked by the dimension ''neuroticism'', has a strong effect on emotional reactions in different weather conditions. Emotionally stable individuals are more ''resistant'' to the weather influence on their emotions, while those who are emotionally unstable have a stronger dependence on the impacts of weather.

  16. Hygroscopic analysis of individual Beijing haze aerosol particles by environmental scanning electron microscopy

    Science.gov (United States)

    Bai, Zhangpeng; Ji, Yuan; Pi, Yiqun; Yang, Kaixiang; Wang, Li; Zhang, Yinqi; Zhai, Yadi; Yan, Zhengguang; Han, Xiaodong

    2018-01-01

    Investigating the hygroscopic behavior of haze aerosol particles is essential for understanding their physicochemical properties and their impacts on regional weather and visibility. An environmental scanning electron microscope equipped with a home-made transmission-scattering electron imaging setup and an energy dispersive spectrometer was used for in-situ observations of pure water-soluble (WS) salts and Beijing haze particles. This imaging setup showed obvious advantages for improving the resolution and acquiring internal information of mixed particles in hydrated environments. We measured the deliquescence relative humidity of pure NaCl, NH4NO3, and (NH4)2SO4 by deliquescence-crystallization processes with an accuracy of up to 0.3% RH. The mixed haze particles showed hygroscopic activation like water uptake and morphological changes when they included WS components such as nitrates, sulfates, halides, ammoniums, and alkali metal salts. In addition, the hygroscopic behavior provides complementary information for analyzing possible phases in mixed haze particles.

  17. Bound Electron States in Skew-symmetric Quantum Wire Intersections

    Science.gov (United States)

    2014-01-01

    STATEMENT OF THE PROBLEM 29 proper normalization, the H = 32 ma2 γ 2 + 2γ + 3 6 + 11γ (2.29) Consequently, we are looking to the variational parameter γ...E0 = H = 32 ma2 3(γ + 1) 11 = 6 11 2 mγ2 (γ + 1) = 1.058 2 ma2 (2.33) This result is obviously an approximation. The true value of the ground...state energy is less than E0. However, the obtained energy values is below the threshold energy obtained in the previous section: Ecr = π 2 8 2 ma2

  18. [COMPUTER ASSISTED DESIGN AND ELECTRON BEAMMELTING RAPID PROTOTYPING METAL THREE-DIMENSIONAL PRINTING TECHNOLOGY FOR PREPARATION OF INDIVIDUALIZED FEMORAL PROSTHESIS].

    Science.gov (United States)

    Liu, Hongwei; Weng, Yiping; Zhang, Yunkun; Xu, Nanwei; Tong, Jing; Wang, Caimei

    2015-09-01

    To study the feasibility of preparation of the individualized femoral prosthesis through computer assisted design and electron beammelting rapid prototyping (EBM-RP) metal three-dimensional (3D) printing technology. One adult male left femur specimen was used for scanning with 64-slice spiral CT; tomographic image data were imported into Mimics15.0 software to reconstruct femoral 3D model, then the 3D model of individualized femoral prosthesis was designed through UG8.0 software. Finally the 3D model data were imported into EBM-RP metal 3D printer to print the individualized sleeve. According to the 3D model of individualized prosthesis, customized sleeve was successfully prepared through the EBM-RP metal 3D printing technology, assembled with the standard handle component of SR modular femoral prosthesis to make the individualized femoral prosthesis. Customized femoral prosthesis accurately matching with metaphyseal cavity can be designed through the thin slice CT scanning and computer assisted design technology. Titanium alloy personalized prosthesis with complex 3D shape, pore surface, and good matching with metaphyseal cavity can be manufactured by the technology of EBM-RP metal 3D printing, and the technology has convenient, rapid, and accurate advantages.

  19. Method for reducing power consumption in a state retaining circuit, state reaining circuit and electronic device.

    NARCIS (Netherlands)

    2006-01-01

    A method for reducing the power consumption in a state retaining circuit during a standby mode is disclosed comprising, in an active state, providing a regular power supply (VDD) and a standby power supply (VDD STANDBY) to the state retaining circuit; for a transition from an active state to a

  20. Efficiency at rest: magnetoencephalographic resting-state connectivity and individual differences in verbal working memory.

    Science.gov (United States)

    del Río, David; Cuesta, Pablo; Bajo, Ricardo; García-Pacios, Javier; López-Higes, Ramón; del-Pozo, Francisco; Maestú, Fernando

    2012-11-01

    Inter-individual differences in cognitive performance are based on an efficient use of task-related brain resources. However, little is known yet on how these differences might be reflected on resting-state brain networks. Here we used Magnetoencephalography resting-state recordings to assess the relationship between a behavioral measurement of verbal working memory and functional connectivity as measured through Mutual Information. We studied theta (4-8 Hz), low alpha (8-10 Hz), high alpha (10-13 Hz), low beta (13-18 Hz) and high beta (18-30 Hz) frequency bands. A higher verbal working memory capacity was associated with a lower mutual information in the low alpha band, prominently among right-anterior and left-lateral sensors. The results suggest that an efficient brain organization in the domain of verbal working memory might be related to a lower resting-state functional connectivity across large-scale brain networks possibly involving right prefrontal and left perisylvian areas. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. One-dimensional electron transport and thermopower in an individual InSb nanowire

    International Nuclear Information System (INIS)

    Zhou, F; Seol, J H; Moore, A L; Shi, L; Ye, Q L; Scheffler, R

    2006-01-01

    We have measured the electrical conductance and thermopower of a single InSb nanowire in the temperature range from 5 to 340 K. Below temperature (T) 220 K, the conductance (G) shows a power-law dependence on T and the current (I)-voltage (V) curve follows a power-law dependence on V at large bias voltages. These features are the characteristics of one-dimensional Luttinger liquid (LL) transport. The thermopower (S) also shows linear temperature dependence for T below 220 K, in agreement with the theoretical prediction based on the LL model. Above 220 K, the power law and linear behaviours respectively in the G-T and S-T curves persist but with different slopes from those at low temperatures. The slope changes can be explained by a transition from a single-mode LL state to a multi-mode LL state

  2. Two-electron states in double quantum dot in direct electric field

    International Nuclear Information System (INIS)

    Burdov, V.A.

    2001-01-01

    One determined analytically the wave functions of stationary states and the spectrum of two-electron system in symmetric binary quantum point. It is shown that in the normal state at the absence of external electric field the electrons due to the Coulomb blockade can not be collectively in one quantum point. In the external electric field the situation changes. When a certain critical value of field intensity is reached the probability of detection of both electrons in one quantum point by a jump increases from zero up to 1 [ru

  3. The Development Strategies of Electronic Records: United States, Canada, United Kingdom and Australia as Examples

    Directory of Open Access Journals (Sweden)

    Chiao-Min Lin

    2004-09-01

    Full Text Available The development of electronic records have been an indicator of modern government all over the world. The format of public records of government agencies have been gradually transformed to digitalform. How to manage the life cycle of electronic records have became an important issue. In this paper, the development strategies in electronic records of the United States, Canada, United Kingdom and Australia are taken as examples to explain their state-of-the-art. Several suggestions are proposed as the reference for Taiwan’s government. [Article content in Chinese

  4. Development of a SEM-based low-energy in-line electron holography microscope for individual particle imaging.

    Science.gov (United States)

    Adaniya, Hidehito; Cheung, Martin; Cassidy, Cathal; Yamashita, Masao; Shintake, Tsumoru

    2018-05-01

    A new SEM-based in-line electron holography microscope has been under development. The microscope utilizes conventional SEM and BF-STEM functionality to allow for rapid searching of the specimen of interest, seamless interchange between SEM, BF-STEM and holographic imaging modes, and makes use of coherent low-energy in-line electron holography to obtain low-dose, high-contrast images of light element materials. We report here an overview of the instrumentation and first experimental results on gold nano-particles and carbon nano-fibers for system performance tests. Reconstructed images obtained from the holographic imaging mode of the new microscope show substantial image contrast and resolution compared to those acquired by SEM and BF-STEM modes, demonstrating the feasibility of high-contrast imaging via low-energy in-line electron holography. The prospect of utilizing the new microscope to image purified biological specimens at the individual particle level is discussed and electron optical issues and challenges to further improve resolution and contrast are considered. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Three-dimensional imaging of individual point defects using selective detection angles in annular dark field scanning transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Jared M.; Im, Soohyun; Windl, Wolfgang; Hwang, Jinwoo, E-mail: hwang.458@osu.edu

    2017-01-15

    We propose a new scanning transmission electron microscopy (STEM) technique that can realize the three-dimensional (3D) characterization of vacancies, lighter and heavier dopants with high precision. Using multislice STEM imaging and diffraction simulations of β-Ga{sub 2}O{sub 3} and SrTiO{sub 3}, we show that selecting a small range of low scattering angles can make the contrast of the defect-containing atomic columns substantially more depth-dependent. The origin of the depth-dependence is the de-channeling of electrons due to the existence of a point defect in the atomic column, which creates extra “ripples” at low scattering angles. The highest contrast of the point defect can be achieved when the de-channeling signal is captured using the 20–40 mrad detection angle range. The effect of sample thickness, crystal orientation, local strain, probe convergence angle, and experimental uncertainty to the depth-dependent contrast of the point defect will also be discussed. The proposed technique therefore opens new possibilities for highly precise 3D structural characterization of individual point defects in functional materials. - Highlights: • A new electron microscopy technique that can visualize 3D position of point defect is proposed. • The technique relies on the electron de-channeling signals at low scattering angles. • The technique enables precise determination of the depth of vacancies and lighter impurity atoms.

  6. Differential cross sections for intermediate-energy electron scattering from α-tetrahydrofurfuryl alcohol: Excitation of electronic-states

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, L.; Jones, D. B.; Thorn, P. A.; Pettifer, Z. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Duque, H. V. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG (Brazil); Silva, G. B. da [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Universidade Federal de Mato Grosso, Barra do Garças, Mato Grosso (Brazil); Limão-Vieira, P. [Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Duflot, D. [Laboratoire de Physique des Lasers, Atomes et Molécules, UMR CNRS 8523, Université Lille, F-59655 Villeneuve d’Ascq Cedex (France); Hubin-Franskin, M.-J.; Delwiche, J. [Départment de Chimie, Université de Liège, Institut de Chimie-Bât. B6C, B-4000 Liège 1 (Belgium); Blanco, F. [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid E-28040 (Spain); García, G. [Instituto de Física Fundamental, CSIC, Madrid E-28006 (Spain); and others

    2014-07-14

    We report on measurements of differential cross sections (DCSs) for electron impact excitation of a series of Rydberg electronic-states in α-tetrahydrofurfuryl alcohol (THFA). The energy range of these experiments was 20–50 eV, while the scattered electron was detected in the 10°–90° angular range. There are currently no other experimental data or theoretical computations against which we can directly compare the present measured results. Nonetheless, we are able to compare our THFA DCSs with earlier cross section measurements for Rydberg-state electronic excitation for tetrahydrofuran, a similar cyclic ether, from Do et al. [J. Chem. Phys. 134, 144302 (2011)]. In addition, “rotationally averaged” elastic DCSs, calculated using our independent atom model with screened additivity rule correction approach are also reported. Those latter results give integral cross sections consistent with the optical theorem, and supercede those from the only previous study of Milosavljević et al. [Eur. Phys. J. D 40, 107 (2006)].

  7. Coupling-Induced Bipartite Pointer States in Arrays of Electron Billiards: Quantum Darwinism in Action?

    Science.gov (United States)

    Brunner, R.; Akis, R.; Ferry, D. K.; Kuchar, F.; Meisels, R.

    2008-07-01

    We discuss a quantum system coupled to the environment, composed of an open array of billiards (dots) in series. Beside pointer states occurring in individual dots, we observe sets of robust states which arise only in the array. We define these new states as bipartite pointer states, since they cannot be described in terms of simple linear combinations of robust single-dot states. The classical existence of bipartite pointer states is confirmed by comparing the quantum-mechanical and classical results. The ability of the robust states to create “offspring” indicates that quantum Darwinism is in action.

  8. Incident ion charge state dependence of electron emission during slow multicharged ion-surface interactions

    International Nuclear Information System (INIS)

    Hughes, I.G.; Zeijlmans van Emmichoven, P.A.; Havener, C.C.; Overbury, S.H.; Robinson, M.T.; Zehner, D.M.; Meyer, F.W.

    1992-01-01

    Characteristic variations in the total electron yield γ as a function of crystal azimuthal orientation are reported for slow N 2+ , N 5+ and N 6+ ions incident on a Au(011) single crystal, together with measurements of γ as a function of incident ion velocity. Kinetic electron emission is shown to arise predominantly in close collisions between incident ions and target atoms, and potential electron emission is found to be essentially constant within our present velocity range. The incident ion charge state is shown to play no role in kinetic electron emission. Extremely fast neutralization times of the order of 10 - 15 secs are needed to explain the observations

  9. Electronic and structural ground state of heavy alkali metals at high pressure

    Science.gov (United States)

    Fabbris, G.; Lim, J.; Veiga, L. S. I.; Haskel, D.; Schilling, J. S.

    2015-02-01

    Alkali metals display unexpected properties at high pressure, including emergence of low-symmetry crystal structures, which appear to occur due to enhanced electronic correlations among the otherwise nearly free conduction electrons. We investigate the high-pressure electronic and structural ground state of K, Rb, and Cs using x-ray absorption spectroscopy and x-ray diffraction measurements together with a b i n i t i o theoretical calculations. The sequence of phase transitions under pressure observed at low temperature is similar in all three heavy alkalis except for the absence of the o C 84 phase in Cs. Both the experimental and theoretical results point to pressure-enhanced localization of the valence electrons characterized by pseudogap formation near the Fermi level and strong s p d hybridization. Although the crystal structures predicted to host magnetic order in K are not observed, the localization process appears to drive these alkalis closer to a strongly correlated electron state.

  10. Cyclic electron flow is redox-controlled but independent of state transition.

    Science.gov (United States)

    Takahashi, Hiroko; Clowez, Sophie; Wollman, Francis-André; Vallon, Olivier; Rappaport, Fabrice

    2013-01-01

    Photosynthesis is the biological process that feeds the biosphere with reduced carbon. The assimilation of CO2 requires the fine tuning of two co-existing functional modes: linear electron flow, which provides NADPH and ATP, and cyclic electron flow, which only sustains ATP synthesis. Although the importance of this fine tuning is appreciated, its mechanism remains equivocal. Here we show that cyclic electron flow as well as formation of supercomplexes, thought to contribute to the enhancement of cyclic electron flow, are promoted in reducing conditions with no correlation with the reorganization of the thylakoid membranes associated with the migration of antenna proteins towards Photosystems I or II, a process known as state transition. We show that cyclic electron flow is tuned by the redox power and this provides a mechanistic model applying to the entire green lineage including the vast majority of the cases in which state transition only involves a moderate fraction of the antenna.

  11. Visualizing One-Dimensional Electronic States and their Scattering in Semi-conducting Nanowires

    Science.gov (United States)

    Beidenkopf, Haim; Reiner, Jonathan; Norris, Andrew; Nayak, Abhay Kumar; Avraham, Nurit; Shtrikman, Hadas

    One-dimensional electronic systems constitute a fascinating playground for the emergence of exotic electronic effects and phases, within and beyond the Tomonaga-Luttinger liquid paradigm. More recently topological superconductivity and Majorana modes were added to that long list of phenomena. We report scanning tunneling microscopy and spectroscopy measurements conducted on pristine, epitaxialy grown InAs nanowires. We resolve the 1D electronic band structure manifested both via Van-Hove singularities in the local density-of-states, as well as by the quasi-particle interference patterns, induced by scattering from surface impurities. By studying the scattering of the one-dimensional electronic states off various scatterers, including crystallographic defects and the nanowire end, we identify new one-dimensional relaxation regimes and yet unexplored effects of interactions. Some of these may bear implications on the topological superconducting state and Majorana modes therein. The authors acknowledge support from the Israeli Science Foundation (ISF).

  12. Statistical electron correlation coefficients for the five lowest states of the heliumlike ions

    International Nuclear Information System (INIS)

    Thakkar, A.J.; Smith, V.H. Jr.

    1981-01-01

    Statistical correlation coefficients were introduced by Kutzelnigg, Del Re, and Berthier to provide overall measures of the difference between the electron pair density and the product of one-electron densities in atoms and molecules. Some properties of these coefficients are discussed, and it is shown that an angular correlation coefficient is experimentally accessible. Radial and angular correlation coefficients are computed from highly accurate wave functions for the 1 1 S, 2 3 S, 2 1 S, 2 3 P, and 2 1 P states of the heliumlike ions from He through Mg 10+ . It is found that positive angular correlation coefficients occur in the 2 1 P state of the two-electron positive ions but not in neutral helium. Moreover, the angular correlation coefficients for the 2 1 S and 2 3 S states of the positively charged two-electron ions show that a previously proposed reformulation of Hund's rule is incorrect

  13. Inferential statistics of electron backscatter diffraction data from within individual crystalline grains

    DEFF Research Database (Denmark)

    Bachmann, Florian; Hielscher, Ralf; Jupp, Peter E.

    2010-01-01

    -spatial statistical analysis adapts ideas borrowed from the Bingham quaternion distribution on . Special emphasis is put on the mathematical definition and the numerical determination of a `mean orientation' characterizing the crystallographic grain as well as on distinguishing several types of symmetry......Highly concentrated distributed crystallographic orientation measurements within individual crystalline grains are analysed by means of ordinary statistics neglecting their spatial reference. Since crystallographic orientations are modelled as left cosets of a given subgroup of SO(3), the non...... of the orientation distribution with respect to the mean orientation, like spherical, prolate or oblate symmetry. Applications to simulated as well as to experimental data are presented. All computations have been done with the free and open-source texture toolbox MTEX....

  14. Systemic Case Formulation, Individualized Process Monitoring, and State Dynamics in a Case of Dissociative Identity Disorder.

    Science.gov (United States)

    Schiepek, Günter K; Stöger-Schmidinger, Barbara; Aichhorn, Wolfgang; Schöller, Helmut; Aas, Benjamin

    2016-01-01

    Objective: The aim of this case report is to demonstrate the feasibility of a systemic procedure (synergetic process management) including modeling of the idiographic psychological system and continuous high-frequency monitoring of change dynamics in a case of dissociative identity disorder. The psychotherapy was realized in a day treatment center with a female client diagnosed with borderline personality disorder (BPD) and dissociative identity disorder. Methods: A three hour long co-creative session at the beginning of the treatment period allowed for modeling the systemic network of the client's dynamics of cognitions, emotions, and behavior. The components (variables) of this idiographic system model (ISM) were used to create items for an individualized process questionnaire for the client. The questionnaire was administered daily through an internet-based monitoring tool (Synergetic Navigation System, SNS), to capture the client's individual change process continuously throughout the therapy and after-care period. The resulting time series were reflected by therapist and client in therapeutic feedback sessions. Results: For the client it was important to see how the personality states dominating her daily life were represented by her idiographic system model and how the transitions between each state could be explained and understood by the activating and inhibiting relations between the cognitive-emotional components of that system. Continuous monitoring of her cognitions, emotions, and behavior via SNS allowed for identification of important triggers, dynamic patterns, and psychological mechanisms behind seemingly erratic state fluctuations. These insights enabled a change in management of the dynamics and an intensified trauma-focused therapy. Conclusion: By making use of the systemic case formulation technique and subsequent daily online monitoring, client and therapist continuously refer to detailed visualizations of the mental and behavioral network and

  15. Systemic Case Formulation, Individualized Process Monitoring, and State Dynamics in a Case of Dissociative Identity Disorder.

    Directory of Open Access Journals (Sweden)

    Guenter Karl Schiepek

    2016-10-01

    Full Text Available Objective. The aim of this case report is to demonstrate the feasibility of a systemic procedure (synergetic process management including modeling of the idiographic psychological system and continuous high-frequency monitoring of change dynamics in a case of dissociative identity disorder. The psychotherapy was realized in a day treatment center with a female client diagnosed with borderline personality disorder (BPD and dissociative identity disorder. Methods. A three hour long co-creative session at the beginning of the treatment period allowed for modeling the systemic network of the client’s dynamics of cognitions, emotions, and behavior. The components (variables of this idiographic system model (ISM were used to create items for an individualized process questionnaire for the client. The questionnaire was administered daily through an internet-based monitoring tool (Synergetic Navigation System, SNS, to capture the client’s individual change process continuously throughout the therapy and after-care period. The resulting time series were reflected by therapist and client in therapeutic feedback sessions. Results. For the client it was important to see how the personality states dominating her daily life were represented by her idiographic system model and how the transitions between each state could be explained and understood by the activating and inhibiting relations between the cognitive-emotional components of that system. Continuous monitoring of her cognitions, emotions, and behavior via SNS allowed for identification of important triggers, dynamic patterns, and psychological mechanisms behind seemingly erratic state fluctuations. These insights enabled a change in management of the dynamics and an intensified trauma-focused therapy. Conclusion. By making use of the systemic case formulation technique and subsequent daily online monitoring, client and therapist continuously refer to detailed visualizations of the mental and

  16. Electronic interconnects and devices with topological surface states and methods for fabricating same

    Science.gov (United States)

    Yazdani, Ali; Ong, N. Phuan; Cava, Robert J.

    2016-05-03

    An interconnect is disclosed with enhanced immunity of electrical conductivity to defects. The interconnect includes a material with charge carriers having topological surface states. Also disclosed is a method for fabricating such interconnects. Also disclosed is an integrated circuit including such interconnects. Also disclosed is a gated electronic device including a material with charge carriers having topological surface states.

  17. A new method for detecting the contribution of high Rydberg states to electron-ion recombination

    International Nuclear Information System (INIS)

    Orban, I; Boehm, S; Fogle, M; Paal, A; Schuch, R

    2007-01-01

    A position sensitive detector for measuring field ionized electrons in the fringe field of a dipole magnet is presented. The detector provides a means to study, in a state selective fashion, recombination into high Rydberg states and offers a new method to investigate recombination enhancement effects. Several experimental considerations and possibilities are discussed in the text

  18. Electronic interconnects and devices with topological surface states and methods for fabricating same

    Energy Technology Data Exchange (ETDEWEB)

    Yazdani, Ali; Ong, N. Phuan; Cava, Robert J.

    2017-04-04

    An interconnect is disclosed with enhanced immunity of electrical conductivity to defects. The interconnect includes a material with charge carriers having topological surface states. Also disclosed is a method for fabricating such interconnects. Also disclosed is an integrated circuit including such interconnects. Also disclosed is a gated electronic device including a material with charge carriers having topological surface states.

  19. Protecting the privacy of individual general practice patient electronic records for geospatial epidemiology research.

    Science.gov (United States)

    Mazumdar, Soumya; Konings, Paul; Hewett, Michael; Bagheri, Nasser; McRae, Ian; Del Fante, Peter

    2014-12-01

    General practitioner (GP) practices in Australia are increasingly storing patient information in electronic databases. These practice databases can be accessed by clinical audit software to generate reports that inform clinical or population health decision making and public health surveillance. Many audit software applications also have the capacity to generate de-identified patient unit record data. However, the de-identified nature of the extracted data means that these records often lack geographic information. Without spatial references, it is impossible to build maps reflecting the spatial distribution of patients with particular conditions and needs. Links to socioeconomic, demographic, environmental or other geographically based information are also not possible. In some cases, relatively coarse geographies such as postcode are available, but these are of limited use and researchers cannot undertake precision spatial analyses such as calculating travel times. We describe a method that allows researchers to implement meaningful mapping and spatial epidemiological analyses of practice level patient data while preserving privacy. This solution has been piloted in a diabetes risk research project in the patient population of a practice in Adelaide. The method offers researchers a powerful means of analysing geographic clinic data in a privacy-protected manner. © 2014 Public Health Association of Australia.

  20. Towards weighing individual atoms by high-angle scattering of electrons

    Energy Technology Data Exchange (ETDEWEB)

    Argentero, G.; Mangler, C.; Kotakoski, J.; Eder, F.R.; Meyer, J.C., E-mail: Jannik.Meyer@univie.ac.at

    2015-04-15

    We consider theoretically the energy loss of electrons scattered to high angles when assuming that the primary beam can be limited to a single atom. We discuss the possibility of identifying the isotopes of light elements and of extracting information about phonons in this signal. The energy loss is related to the mass of the much heavier nucleus, and is spread out due to atomic vibrations. Importantly, while the width of the broadening is much larger than the energy separation of isotopes, only the shift in the peak positions must be detected if the beam is limited to a single atom. We conclude that the experimental case will be challenging but is not excluded by the physical principles as far as considered here. Moreover, the initial experiments demonstrate that the separation of gold and carbon based on a signal that is related to their mass, rather than their atomic number. - Highlights: • We explore how energy loss spectroscopy could be used to obtain information about the mass, rather than the charge, of atoms. • The dose and precision that would be needed to distinguish between the two isotopes of carbon, C12 and C13, is estimated. • Signal broadening due to phonons is included in the calculation. • Initial experiments show the separation between gold and carbon based on their mass rather than charge.

  1. Coherence Properties of Individual Femtosecond Pulses of an X-ray Free-Electron Laser

    Energy Technology Data Exchange (ETDEWEB)

    Vartanyants, I.A.; /DESY /Moscow Phys. Eng. Inst.; Singer, A.; Mancuso, A.P.; Yefanov, O.M.; /DESY; Sakdinawat, A.; Liu, Y.; Bang, E.; /UC, Berkeley; Williams, G.J.; /SLAC; Cadenazzi, G.; Abbey, B.; /Melbourne U.; Sinn, H.; /European XFEL, Hamburg; Attwood, D.; /UC, Berkeley; Nugent, K.A.; /Melbourne U.; Weckert, E.; /DESY; Wang, T.; Zhu, D.; Wu, B.; Graves, C.; Scherz, A.; Turner, J.J.; Schlotter, W.F.; /SLAC /LERMA, Ivry /Zurich, ETH /LBL, Berkeley /ANL, APS /Argonne /SLAC /LLNL, Livermore /Latrobe U. /SLAC /SLAC /European XFEL, Hamburg /SLAC /Hamburg U.

    2012-06-06

    Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in 'diffract-and-destroy' mode. We determined a coherence length of 17 {micro}m in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.

  2. Broadband 2D Electronic Spectroscopy Reveals Coupling Between Dark 1Bu- State of Carotenoid and Qx State of Bacteriochlorophyll

    Directory of Open Access Journals (Sweden)

    Scholes Gregory D.

    2013-03-01

    Full Text Available The study of LH2 protein of purple bacteria by broadband 2D electronic spectroscopy is presented. The dark 1Bu- carotenoid state is directly observed in 2D spectra and its role in carotenoid-bacteriochlorophyll interaction is discussed.

  3. Toward the Computational Representation of Individual Cultural, Cognitive, and Physiological State: The Sensor Shooter Simulation; TOPICAL

    International Nuclear Information System (INIS)

    RAYBOURN, ELAINE M.; FORSYTHE, JAMES C.

    2001-01-01

    This report documents an exploratory FY 00 LDRD project that sought to demonstrate the first steps toward a realistic computational representation of the variability encountered in individual human behavior. Realism, as conceptualized in this project, required that the human representation address the underlying psychological, cultural, physiological, and environmental stressors. The present report outlines the researchers' approach to representing cognitive, cultural, and physiological variability of an individual in an ambiguous situation while faced with a high-consequence decision that would greatly impact subsequent events. The present project was framed around a sensor-shooter scenario as a soldier interacts with an unexpected target (two young Iraqi girls). A software model of the ''Sensor Shooter'' scenario from Desert Storm was developed in which the framework consisted of a computational instantiation of Recognition Primed Decision Making in the context of a Naturalistic Decision Making model[1]. Recognition Primed Decision Making was augmented with an underlying foundation based on our current understanding of human neurophysiology and its relationship to human cognitive processes. While the Gulf War scenario that constitutes the framework for the Sensor Shooter prototype is highly specific, the human decision architecture and the subsequent simulation are applicable to other problems similar in concept, intensity, and degree of uncertainty. The goal was to provide initial steps toward a computational representation of human variability in cultural, cognitive, and physiological state in order to attain a better understanding of the full depth of human decision-making processes in the context of ambiguity, novelty, and heightened arousal

  4. Model of charge-state distributions for electron cyclotron resonance ion source plasmas

    Directory of Open Access Journals (Sweden)

    D. H. Edgell

    1999-12-01

    Full Text Available A computer model for the ion charge-state distribution (CSD in an electron cyclotron resonance ion source (ECRIS plasma is presented that incorporates non-Maxwellian distribution functions, multiple atomic species, and ion confinement due to the ambipolar potential well that arises from confinement of the electron cyclotron resonance (ECR heated electrons. Atomic processes incorporated into the model include multiple ionization and multiple charge exchange with rate coefficients calculated for non-Maxwellian electron distributions. The electron distribution function is calculated using a Fokker-Planck code with an ECR heating term. This eliminates the electron temperature as an arbitrary user input. The model produces results that are a good match to CSD data from the ANL-ECRII ECRIS. Extending the model to 1D axial will also allow the model to determine the plasma and electrostatic potential profiles, further eliminating arbitrary user input to the model.

  5. Chirality-Assisted Electronic Cloaking of Confined States in Bilayer Graphene

    Science.gov (United States)

    Gu, Nan; Rudner, Mark; Levitov, Leonid

    2011-10-01

    We show that the strong coupling of pseudospin orientation and charge carrier motion in bilayer graphene has a drastic effect on transport properties of ballistic p-n-p junctions. Electronic states with zero momentum parallel to the barrier are confined under it for one pseudospin orientation, whereas states with the opposite pseudospin tunnel through the junction totally uninfluenced by the presence of confined states. We demonstrate that the junction acts as a cloak for confined states, making them nearly invisible to electrons in the outer regions over a range of incidence angles. This behavior is manifested in the two-terminal conductance as transmission resonances with non-Lorentzian, singular peak shapes. The response of these phenomena to a weak magnetic field or electric-field-induced interlayer gap can serve as an experimental fingerprint of electronic cloaking.

  6. Determination of many-electron basis functions for a quantum Hall ground state using Schur polynomials

    Science.gov (United States)

    Mandal, Sudhansu S.; Mukherjee, Sutirtha; Ray, Koushik

    2018-03-01

    A method for determining the ground state of a planar interacting many-electron system in a magnetic field perpendicular to the plane is described. The ground state wave-function is expressed as a linear combination of a set of basis functions. Given only the flux and the number of electrons describing an incompressible state, we use the combinatorics of partitioning the flux among the electrons to derive the basis wave-functions as linear combinations of Schur polynomials. The procedure ensures that the basis wave-functions form representations of the angular momentum algebra. We exemplify the method by deriving the basis functions for the 5/2 quantum Hall state with a few particles. We find that one of the basis functions is precisely the Moore-Read Pfaffian wave function.

  7. Electronic Entanglement Concentration for the Concatenated Greenberger-Horne-Zeilinger State

    Science.gov (United States)

    Ding, Shang-Ping; Zhou, Lan; Gu, Shi-Pu; Wang, Xing-Fu; Sheng, Yu-Bo

    2017-06-01

    Concatenated Greenberger-Horne-Zeilinger (C-GHZ) state, which encodes many physical qubits in a logic qubit will have important applications in both quantum communication and computation. In this paper, we will describe an entanglement concentration protocol (ECP) for electronic C-GHZ state, by exploiting the electronic polarization beam splitters (PBSs) and charge detection. This protocol has several advantages. First, the parties do not need to know the exact coefficients of the initial less-entangled C-GHZ state, which makes this protocol feasible. Second, with the help of charge detection, the distilled maximally entangled C-GHZ state can be remained for future application. Third, this protocol can be repeated to obtain a higher success probability. We hope that this protocol can be useful in future quantum computation based on electrons.

  8. Spin eigen-states of Dirac equation for quasi-two-dimensional electrons

    Energy Technology Data Exchange (ETDEWEB)

    Eremko, Alexander, E-mail: eremko@bitp.kiev.ua [Bogolyubov Institute for Theoretical Physics, Metrologichna Sttr., 14-b, Kyiv, 03680 (Ukraine); Brizhik, Larissa, E-mail: brizhik@bitp.kiev.ua [Bogolyubov Institute for Theoretical Physics, Metrologichna Sttr., 14-b, Kyiv, 03680 (Ukraine); Loktev, Vadim, E-mail: vloktev@bitp.kiev.ua [Bogolyubov Institute for Theoretical Physics, Metrologichna Sttr., 14-b, Kyiv, 03680 (Ukraine); National Technical University of Ukraine “KPI”, Peremohy av., 37, Kyiv, 03056 (Ukraine)

    2015-10-15

    Dirac equation for electrons in a potential created by quantum well is solved and the three sets of the eigen-functions are obtained. In each set the wavefunction is at the same time the eigen-function of one of the three spin operators, which do not commute with each other, but do commute with the Dirac Hamiltonian. This means that the eigen-functions of Dirac equation describe three independent spin eigen-states. The energy spectrum of electrons confined by the rectangular quantum well is calculated for each of these spin states at the values of energies relevant for solid state physics. It is shown that the standard Rashba spin splitting takes place in one of such states only. In another one, 2D electron subbands remain spin degenerate, and for the third one the spin splitting is anisotropic for different directions of 2D wave vector.

  9. Evaluation of behavioral states among morning and evening active healthy individuals

    Directory of Open Access Journals (Sweden)

    M.P. Hidalgo

    2002-07-01

    Full Text Available The Horne-Östberg questionnaire partly covers some factors that may be important determinants of peak time and characterize patterns of behavior. We conducted a study for the evaluation of self-reported behavioral states (hunger sensation, availability for study, physical exercise, solving daily problems, and time preferences as expressions of underlying cyclic activity. Three hundred and eighteen community subjects without history of medical, psychiatric, or sleep disorders were evaluated in a cross-sectional design. A self-report about daily highest level of activity was used to categorize individuals into morning, evening, and indifferently active. Time-related behavioral states were evaluated with 23 visual analog questions. The responses to most analogic questions were significantly different between morning and evening active subjects. Logistic regression analysis identified a group of behaviors more strongly associated with the self-reported activity pattern (common wake up time, highest subjective fatigue, as well as wake up, bedtime, exercise and study preferences. These findings suggested that the patterns of activity presented by normal adults were related to specific common behavioral characteristics that may contribute to peak time.

  10. A simple parameter-free wavefunction for the ground state of two-electron atoms

    International Nuclear Information System (INIS)

    Ancarani, L U; Rodriguez, K V; Gasaneo, G

    2007-01-01

    We propose a simple and pedagogical wavefunction for the ground state of two-electron atoms which (i) is parameter free (ii) satisfies all two-particle cusp conditions (iii) yields reasonable ground-state energies, including the prediction of a bound state for H - . The mean energy, and other mean physical quantities, is evaluated analytically. The simplicity of the result can be useful as an easy-to-use wavefunction when testing collision models

  11. Antiferroic electronic structure in the nonmagnetic superconducting state of the iron-based superconductors.

    Science.gov (United States)

    Shimojima, Takahiro; Malaeb, Walid; Nakamura, Asuka; Kondo, Takeshi; Kihou, Kunihiro; Lee, Chul-Ho; Iyo, Akira; Eisaki, Hiroshi; Ishida, Shigeyuki; Nakajima, Masamichi; Uchida, Shin-Ichi; Ohgushi, Kenya; Ishizaka, Kyoko; Shin, Shik

    2017-08-01

    A major problem in the field of high-transition temperature ( T c ) superconductivity is the identification of the electronic instabilities near superconductivity. It is known that the iron-based superconductors exhibit antiferromagnetic order, which competes with the superconductivity. However, in the nonmagnetic state, there are many aspects of the electronic instabilities that remain unclarified, as represented by the orbital instability and several in-plane anisotropic physical properties. We report a new aspect of the electronic state of the optimally doped iron-based superconductors by using high-energy resolution angle-resolved photoemission spectroscopy. We find spectral evidence for the folded electronic structure suggestive of an antiferroic electronic instability, coexisting with the superconductivity in the nonmagnetic state of Ba 1- x K x Fe 2 As 2 . We further establish a phase diagram showing that the antiferroic electronic structure persists in a large portion of the nonmagnetic phase covering the superconducting dome. These results motivate consideration of a key unknown electronic instability, which is necessary for the achievement of high- T c superconductivity in the iron-based superconductors.

  12. Determination of the individual atomic site contribution to the electronic structure of 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA)

    Energy Technology Data Exchange (ETDEWEB)

    Cho, S. W., E-mail: dio8027@yonsei.ac.kr, E-mail: ksmith@bu.edu [Department of Physics, Yonsei University, Wonju, Gangwon-do 220-710 (Korea, Republic of); Newby, D.; DeMasi, A.; Smith, K. E., E-mail: dio8027@yonsei.ac.kr, E-mail: ksmith@bu.edu [Department of Physics, Boston University, 590 Commonwealth Ave., Boston, Massachusetts 02215 (United States); Piper, L. F. J. [Department of Physics, Applied Physics, and Astronomy, Binghamton University, State University of New York, Binghamton, New York 13902 (United States); Jones, T. S. [Department of Chemistry, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2013-11-14

    We have studied the element and orbital-specific electronic structure of thin films of 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) using a combination of synchrotron radiation-exited resonant x-ray emission spectroscopy, x-ray absorption spectroscopy, x-ray photoelectron spectroscopy, as well as density functional theory calculations. Resonant and non-resonant x-ray emission spectroscopies were used to measure the C and O 2p partial densities of state in PTCDA. Furthermore, resonant x-ray emission at the C and O K-edges is shown to be able to measure the partial densities of states associated with individual atomic sites. The flat molecular orientation of PTCDA on various substrates is explained in terms of the carbonyl O atom acting as a hydrogen-bond acceptor leading to multiple in-plane intermolecular C=O···H−C hydrogen bonding between carbonyl groups and the perylene core of the neighboring PTCDA molecules. We support this conclusion by comparison of our calculations to measurements of the electronic structure using element-, site-, and orbital-selective C and O K-edge resonant x-ray emission spectroscopy, and photoemission spectroscopy.

  13. At loggerheads or in dovetails? The individual and the State from early modern jurisprudence to contemporary international jurisprudence.

    OpenAIRE

    De Lucca, Jean-Paul; Works in Progress Seminars Series

    2012-01-01

    A Works in Progress Seminars Series lecture entitled: At Loggerheads or in dovetails? The individual and the State from early modern jurisprudence to contemporary international jurisprudence. This talk is delivered by Dr Jean Paul De Lucca.

  14. β-globin haplotypes in normal and hemoglobinopathic individuals from Reconcavo Baiano, State of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Wellington dos Santos Silva

    2010-01-01

    Full Text Available Five restriction site polymorphisms in the β-globin gene cluster (HincII-5'ε, HindIII-Gγ, HindIII-ªγ, HincII-'ψβ1 and HincII-3''ψβ1 were analyzed in three populations (n = 114 from Reconcavo Baiano, State of Bahia, Brazil. The groups included two urban populations from the towns of Cachoeira and Maragojipe and one rural Afro-descendant population, known as the "quilombo community", from Cachoeira municipality. The number of haplotypes found in the populations ranged from 10 to 13, which indicated higher diversity than in the parental populations. The haplotypes 2 (+----,3(----+,4(-+--+and6(-++-+onthe βA chromosomes were the most common, and two haplotypes, 9 (-++++and 14 (++--+, were found exclusively in the Maragojipe population. The other haplotypes (1, 5, 9, 11, 12, 13, 14 and 16 had lower frequencies. Restriction site analysis and the derived haplotypes indicated homogeneity among the populations. Thirty-two individuals with hemoglobinopathies (17 sickle cell disease, 12 HbSC disease and 3 HbCC disease were also analyzed. The haplotype frequencies of these patients differed significantly from those of the general population. In the sickle cell disease subgroup, the predominant haplotypes were BEN (Benin and CAR (Central African Republic, with frequencies of 52.9% and 32.4%, respectively. The high frequency of the BEN haplotype agreed with the historical origin of the afro-descendant population in the state of Bahia. However, this frequency differed from that of Salvador, the state capital, where the CAR and BEN haplotypes have similar frequencies, probably as a consequence of domestic slave trade and subsequent internal migrations to other regions of Brazil.

  15. Identifying individuals with antisocial personality disorder using resting-state FMRI.

    Directory of Open Access Journals (Sweden)

    Yan Tang

    Full Text Available Antisocial personality disorder (ASPD is closely connected to criminal behavior. A better understanding of functional connectivity in the brains of ASPD patients will help to explain abnormal behavioral syndromes and to perform objective diagnoses of ASPD. In this study we designed an exploratory data-driven classifier based on machine learning to investigate changes in functional connectivity in the brains of patients with ASPD using resting state functional magnetic resonance imaging (fMRI data in 32 subjects with ASPD and 35 controls. The results showed that the classifier achieved satisfactory performance (86.57% accuracy, 77.14% sensitivity and 96.88% specificity and could extract stabile information regarding functional connectivity that could be used to discriminate ASPD individuals from normal controls. More importantly, we found that the greatest change in the ASPD subjects was uncoupling between the default mode network and the attention network. Moreover, the precuneus, superior parietal gyrus and cerebellum exhibited high discriminative power in classification. A voxel-based morphometry analysis was performed and showed that the gray matter volumes in the parietal lobule and white matter volumes in the precuneus were abnormal in ASPD compared to controls. To our knowledge, this study was the first to use resting-state fMRI to identify abnormal functional connectivity in ASPD patients. These results not only demonstrated good performance of the proposed classifier, which can be used to improve the diagnosis of ASPD, but also elucidate the pathological mechanism of ASPD from a resting-state functional integration viewpoint.

  16. Exact many-electron ground states on diamond and triangle Hubbard chains

    International Nuclear Information System (INIS)

    Gulacsi, Zsolt; Kampf, Arno; Vollhardt, Dieter

    2009-01-01

    We construct exact ground states of interacting electrons on triangle and diamond Hubbard chains. The construction requires (1) a rewriting of the Hamiltonian into positive semidefinite form, (2) the construction of a many-electron ground state of this Hamiltonian, and (3) the proof of the uniqueness of the ground state. This approach works in any dimension, requires no integrability of the model, and only demands sufficiently many microscopic parameters in the Hamiltonian which have to fulfill certain relations. The scheme is first employed to construct exact ground state for the diamond Hubbard chain in a magnetic field. These ground states are found to exhibit a wide range of properties such as flat-band ferromagnetism and correlation induced metallic, half-metallic or insulating behavior, which can be tuned by changing the magnetic flux, local potentials, or electron density. Detailed proofs of the uniqueness of the ground states are presented. By the same technique exact ground states are constructed for triangle Hubbard chains and a one-dimensional periodic Anderson model with nearest-neighbor hybridization. They permit direct comparison with results obtained by variational techniques for f-electron ferromagnetism due to a flat band in CeRh 3 B 2 . (author)

  17. Coherent control of two individual electron spins and influence of hyperfine coupling in a double quantum dot

    International Nuclear Information System (INIS)

    Tarucha, S; Obata, T; Pioro-Ladriere, M; Brunner, R; Shin, Y-S; Kubo, T; Tokura, Y

    2011-01-01

    Electric dipole spin resonance of two individual electrons and the influence of hyperfine coupling on the spin resonance are studied for a double quantum dot equipped with a micro-magnet. The spin resonance occurs by oscillating the electron in each dot at microwave (MW) frequencies in the presence of a micro-magnet induced stray field. The observed continuous wave (CW) and time-resolved spin resonances are consistent with calculations in which the MW induced AC electric field and micro-magnet induced stray field are taken into account. The influence of hyperfine coupling causes an increase and broadening of the respective CW spin resonance peaks through dynamical nuclear polarization when sweeping up the magnetic field. This behaviour appears stronger for the larger of the two spin resonance peaks and in general becomes more pronounced as the MW power increases, both reflecting that the electron-nuclei interaction is more efficient for the stronger spin resonance. In addition the hyperfine coupling effect only becomes pronounced when the MW induced AC magnetic field exceeds the fluctuating nuclear field.

  18. Individual, social, and physical environment factors associated with electronic media use among children: sedentary behavior at home.

    Science.gov (United States)

    Granich, Joanna; Rosenberg, Michael; Knuiman, Matthew W; Timperio, Anna

    2011-07-01

    Individual, home social and physical environment correlates of electronic media (EM) use among children were examined and pattern of differences on school and weekend days. Youth (n = 298) aged 11 to 12 years self-reported time spent using EM (TV, video/DVD, computer use, and electronic games) on a typical school and a weekend day, each dichotomized at the median to indicate heavy and light EM users. Anthropometric measurements were taken. Logistic regression examined correlates of EM use. In total, 87% of participants exceeded electronic media use recommendations of ≤ 2 hrs/day. Watching TV during breakfast (OR = 3.17) and after school (OR = 2.07), watching TV with mother (OR = 1.96), no rule(s) limiting time for computer game usage (OR = 2.30), having multiple (OR = 2.99) EM devices in the bedroom and BMI (OR = 1.15) were associated with higher odds of being heavy EM user on a school day. Boys (OR = 2.35) and participants who usually watched TV at midday (OR = 2.91) and late at night (OR = 2.04) had higher odds of being a heavy EM user on the weekend. Efforts to modify children's EM use should focus on a mix of intervention strategies that address patterns and reinforcement of TV viewing, household rules limiting screen time, and the presence of EM devices in the child's bedroom.

  19. InN/GaN quantum dot superlattices: Charge-carrier states and surface electronic structure

    Science.gov (United States)

    Kanouni, F.; Brezini, A.; Djenane, M.; Zou, Q.

    2018-03-01

    We have theoretically investigated the electron energy spectra and surface states energy in the three dimensionally ordered quantum dot superlattices (QDSLs) made of InN and GaN semiconductors. The QDSL is assumed in this model to be a matrix of GaN containing cubic dots of InN of the same size and uniformly distributed. For the miniband’s structure calculation, the resolution of the effective mass Schrödinger equation is done by decoupling it in the three directions within the framework of Kronig-Penney model. We found that the electrons minibands in infinite ODSLs are clearly different from those in the conventional quantum-well superlattices. The electrons localization and charge-carrier states are very dependent on the quasicrystallographic directions, the size and the shape of the dots which play a role of the artificial atoms in such QD supracrystal. The energy spectrum of the electron states localized at the surface of InN/GaN QDSL is represented by Kronig-Penney like-model, calculated via direct matching procedure. The calculation results show that the substrate breaks symmetrical shape of QDSL on which some localized electronic surface states can be produced in minigap regions. Furthermore, we have noticed that the surface states degeneracy is achieved in like very thin bands located in the minigaps, identified by different quantum numbers nx, ny, nz. Moreover, the surface energy bands split due to the reduction of the symmetry of the QDSL in z-direction.

  20. The steady-state pharmacokinetics of nevirapine during once daily and twice daily dosing in HIV-1-infected individuals

    NARCIS (Netherlands)

    van Heeswijk, R. P.; Veldkamp, A. I.; Mulder, J. W.; Meenhorst, P. L.; Wit, F. W.; Lange, J. M.; Danner, S. A.; Foudraine, N. A.; Kwakkelstein, M. O.; Reiss, P.; Beijnen, J. H.; Hoetelmans, R. M.

    2000-01-01

    OBJECTIVE: To investigate and to compare the steady-state plasma pharmacokinetics of nevirapine in a dosing regimen of 400 mg once daily versus 200 mg twice daily in HIV-1-infected individuals. DESIGN: Open-label, randomized, cross-over study. METHODS: Twenty HIV-1-infected individuals who already

  1. 26 CFR 1.6013-6 - Election to treat nonresident alien individual as resident of the United States.

    Science.gov (United States)

    2010-04-01

    ... reason of the individual's domicile, residence, or citizenship. Under article 4 (1) of the treaty, W is a... both the United States and country X by reason of article 4 (1), the individual shall be deemed to be a... spouses legally separate under a degree of divorce or of separate maintenance. An election that terminates...

  2. Third-order polynomial model for analyzing stickup state laminated structure in flexible electronics

    Science.gov (United States)

    Meng, Xianhong; Wang, Zihao; Liu, Boya; Wang, Shuodao

    2018-02-01

    Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded, twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Third-order polynomials are used to describe the displacement field, and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bi-material region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future.

  3. Ground state of a hydrogen ion molecule immersed in an inhomogeneous electron gas

    International Nuclear Information System (INIS)

    Diaz-Valdes, J.; Gutierrez, F.A.; Matamala, A.R.; Denton, C.D.; Vargas, P.; Valdes, J.E.

    2007-01-01

    In this work we have calculated the ground state energy of the hydrogen molecule, H 2 + , immersed in the highly inhomogeneous electron gas around a metallic surface within the local density approximation. The molecule is perturbed by the electron density of a crystalline surface of Au with the internuclear axis parallel to the surface. The surface spatial electron density is calculated through a linearized band structure method (LMTO-DFT). The ground state of the molecule-ion was calculated using the Born-Oppenheimer approximation for a fixed-ion while the screening effects of the inhomogeneous electron gas are depicted by a Thomas-Fermi like electrostatic potential. We found that within our model the molecular ion dissociates at the critical distance of 2.35a.u. from the first atomic layer of the solid

  4. The influence of autoionizing states on the excitation of helium by electrons

    International Nuclear Information System (INIS)

    Ittersum, T. van

    1976-01-01

    The work described in this thesis deals with resonance effects in the scattering of electrons by helium at energies near the threshold of the autoionizing states (50-70 eV). The investigation is performed by studying light emission following the excitation of singly excited states. In some cases, the polarization of the radiation was also investigated. The purpose of the research was (i) to enlarge our knowledge of triply excited negative ion states, i.e. resonance states which are formed by temporary binding of the incident electron to a doubly excited (autoionizing) state of neutral helium, and (ii) to clear up the nature of some resonance structures which could not be explained in terms of negative ion resonances

  5. The role of the excited electronic states in the C++H2O reaction

    International Nuclear Information System (INIS)

    Flores, Jesus R.; Gonzalez, Adan B.

    2008-01-01

    The electronic excited states of the [COH 2 ] + system have been studied in order to establish their role in the dynamics of the C + +H 2 O→[COH] + +H reaction, which is a prototypical ion-molecule reaction. The most relevant minima and saddle points of the lowest excited state have been determined and energy profiles for the lowest excited doublet and quartet electronic states have been computed along the fragmentation and isomerization coordinates. Also, nonadiabatic coupling strengths between the ground and the first excited state have been computed where they can be large. Our analysis suggests that the first excited state could play an important role in the generation of the formyl isomer, which has been detected in crossed beam experiments [D. M. Sonnenfroh et al., J. Chem. Phys. 83, 3985 (1985)], but could not be explained in quasiclassical trajectory computations [Y. Ishikawa et al., Chem. Phys. Lett. 370, 490 (2003); J. R. Flores, J. Chem. Phys. 125, 164309 (2006)

  6. Electronic states in crystals of finite size quantum confinement of bloch waves

    CERN Document Server

    Ren, Shang Yuan

    2017-01-01

    This book presents an analytical theory of the electronic states in ideal low dimensional systems and finite crystals based on a differential equation theory approach. It provides precise and fundamental understandings on the electronic states in ideal low-dimensional systems and finite crystals, and offers new insights into some of the basic problems in low-dimensional systems, such as the surface states and quantum confinement effects, etc., some of which are quite different from what is traditionally believed in the solid state physics community. Many previous predictions have been confirmed in subsequent investigations by other authors on various relevant problems. In this new edition, the theory is further extended to one-dimensional photonic crystals and phononic crystals, and a general theoretical formalism for investigating the existence and properties of surface states/modes in semi-infinite one-dimensional crystals is developed. In addition, there are various revisions and improvements, including us...

  7. Key electronic states in lithium battery materials probed by soft X-ray spectroscopy

    International Nuclear Information System (INIS)

    Yang, Wanli; Liu, Xiaosong; Qiao, Ruimin; Olalde-Velasco, Paul; Spear, Jonathan D.; Roseguo, Louis; Pepper, John X.; Chuang, Yi-de; Denlinger, Jonathan D.; Hussain, Zahid

    2013-01-01

    Highlights: •Key electronic states in battery materials revealed by soft X-ray spectroscopy. •Soft X-ray absorption consistently probes Mn oxidation states in different systems. •Soft X-ray absorption and emission fingerprint battery operations in LiFePO 4 . •Spectroscopic guidelines for selecting/optimizing polymer materials for batteries. •Distinct SEI formation on same electrode material with different crystal orientations. -- Abstract: The formidable challenges for developing a safe, low-cost, high-capacity, and high-power battery necessitate employing advanced tools that are capable of directly probing the key electronic states relevant to battery performance. Synchrotron based soft X-ray spectroscopy directly measures both the occupied and unoccupied states in the vicinity of the Fermi level, including transition-metal-3d and anion-p states. This article presents the basic concepts on how fundamental physics in electronic structure could provide valuable information for lithium-ion battery applications. We then discuss some of our recent studies on transition-metal oxide based cathodes, silicon based anode, and solid-electrolyte-interphase through soft X-ray absorption and emission spectroscopy. We argue that spectroscopic results reveal the evolution of electronic states for fingerprinting, understanding, and optimizing lithium-ion battery operations

  8. Theoretical study of the lowest-lying electronic states of Aluminium monoiodide

    International Nuclear Information System (INIS)

    Taher, F.; Kabbani, A.; Ani-El Houte, W.

    2004-01-01

    Full text.The spectroscopic study of Aluminium monohalides, especially the Aluminium monoiodide, is important for monitoring such species in high temperature fast-flow reactors. Theoretical calculations of AlI are not available, whereas several studies have been done for the other aluminium monohalides. In this work, CAS-SCF/MRCI calculations are performed for the lowest-lying electronic states of AlI in a range of internuclear distance between 2.30 A and 2.80 A. Ab-initio calculations have been effectuated by using the computational chemistry program Molpro. The basis set used in this study for aluminium atom is that used by Langhoff for aluminium monohalides, of contractions using atomic natural orbitals and a pseudopotential is used for iode. Accurate theoretical spectroscopic constants and potential curves are obtained for the ground state X 1 Σ + and the first excited states a 3 Π and A 1 Π. The calculated values of Te, ωe, ωexe and re of these states are compatible with the experimental results. An ordering of states is represented for the lowest five predicted singlet and lowest five predicted triplet states. These results provide a big support to determine the analogy in the ordering of the electronic states in AlF, AlBr and AlI respectively at lower energies. These theoretical results identify a set of electronic singlet and triplet states unobserved experimentally

  9. Theory of Correlated Pairs of Electrons Oscillating in Resonant Quantum States to Reach the Critical Temperature in a Metal

    OpenAIRE

    Aroche, Raúl Riera; Rosas-Cabrera, Rodrigo Arturo; Burgos, Rodrigo Arturo Rosas; Betancourt-Riera, René; Betancourt-Riera, Ricardo

    2017-01-01

    The formation of Correlated Electron Pairs Oscillating around the Fermi level in Resonant Quantum States (CEPO-RQS), when a metal is cooled to its critical temperature T=Tc, is studied. The necessary conditions for the existence of CEPO-RQS are analyzed. The participation of electron-electron interaction screened by an electron dielectric constant of the form proposed by Thomas Fermi is considered and a physical meaning for the electron-phonon-electron interaction in the formation of the CEPO...

  10. Nanoscale probing of bandgap states on oxide particles using electron energy-loss spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qianlang [School for the Engineering of Matter, Transport and Energy, Arizona State University, 85287 AZ (United States); March, Katia [Laboratoire de Physique des Solides, Bâtiment 510, Université Paris-Sud, 91405 Orsay Cedex (France); Crozier, Peter A., E-mail: CROZIER@asu.edu [School for the Engineering of Matter, Transport and Energy, Arizona State University, 85287 AZ (United States)

    2017-07-15

    Surface and near-surface electronic states were probed with nanometer spatial resolution in MgO and TiO{sub 2} anatase nanoparticles using ultra-high energy resolution electron energy-loss spectroscopy (EELS) coupled to a scanning transmission electron microscope (STEM). This combination allows the surface electronic structure determined with spectroscopy to be correlated with nanoparticle size, morphology, facet etc. By acquiring the spectra in aloof beam mode, radiation damage to the surface can be significantly reduced while maintaining the nanometer spatial resolution. MgO and TiO{sub 2} showed very different bandgap features associated with the surface/sub-surface layer of the nanoparticles. Spectral simulations based on dielectric theory and density of states models showed that a plateau feature found in the pre-bandgap region in the spectra from (100) surfaces of 60 nm MgO nanocubes is consistent with a thin hydroxide surface layer. The spectroscopy shows that this hydroxide species gives rise to a broad filled surface state at 1.1 eV above the MgO valence band. At the surfaces of TiO{sub 2} nanoparticles, pronounced peaks were observed in the bandgap region, which could not be well fitted to defect states. In this case, the high refractive index and large particle size may make Cherenkov or guided light modes the likely causes of the peaks. - Highlights: • Bandgap states detected with aloof beam monochromated EELS on oxide nanoparticle surfaces. • Dielectric theory applied to simulate the spectra and interpret surface structure. • Density of states models also be employed to understand the surface electronic structure. • In MgO, one states associate with water species was found close to the valence band edge. • In anatase, two mid-gap states associated with point defects were found.

  11. Construction of Vibronic Diabatic Hamiltonian for Excited-State Electron and Energy Transfer Processes.

    Science.gov (United States)

    Xie, Yu; Jiang, Shengshi; Zheng, Jie; Lan, Zhenggang

    2017-12-21

    Photoinduced excited-state electron and energy transfer processes are crucial in biological photoharvesting systems and organic photovoltaic devices. We discuss the construction of a diabatic vibronic Hamiltonian for the proper treatment of these processes involving the projection approach acting on both electronic wave functions and vibrational modes. In the electronic part, the wave function projection approach is used to construct the diabatic Hamiltonian in which both local excited states and charge-transfer states are included on the same footing. For the vibrational degrees of freedom, the vibronic couplings in the diabatic Hamiltonian are obtained in the basis of the pseudonormal modes localized on each monomer site by applying delocalized-to-localized mode projection. This systematic approach allows us to construct the vibronic diabatic Hamiltonian in molecular aggregates.

  12. Enhancing the Electronic Conductivity of Vanadium-tellurite Glasses by Tuning the Redox State

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Yue, Yuanzheng

    Transition metal oxides are used in a variety of electronic purposes, e.g., vanadium tellurite as cathode material in high-power demanding batteries. By tuning the redox state of vanadium, it is possible to achieve a lower internal resistance within the entire battery unit, thus a higher capacity....... In this work we vary the redox state of a given vanadium tellurite system by performing post heat-treatment in controlled atmosphere. This process is in theory not limited only to varying electronic conductivity, but also varying the glass structure, and hence, changing properties of the glasses, e.g, thermal...... and mechanical properties. Finally we give insight into the relation between the redox state and electronic conductivity....

  13. 45 CFR 261.61 - How must a State document a work-eligible individual's hours of participation?

    Science.gov (United States)

    2010-10-01

    ... individual who is self-employed, the documentation must comport with standards set forth in the State's approved Work Verification Plan. Self-reporting by a participant without additional verification is not... case file. In accordance with § 261.62, a State must describe in its Work Verification Plan the...

  14. Dissociative electron attachment to vibrationally excited H2 molecules involving the 2Σg+ resonant Rydberg electronic state

    International Nuclear Information System (INIS)

    Celiberto, R.; Janev, R.K.; Wadehra, J.M.; Tennyson, J.

    2012-01-01

    Graphical abstract: Dissociative electron attachment cross sections as a function of the incident electron energy and for the initial vibration levels v i = 0–5, 10 of the H 2 molecule. Highlights: ► We calculated electron–hydrogen dissociative attachment cross sections and rates coefficients. ► Collision processes occurring through a resonant Rydberg state are considered. ► Cross sections and rates were obtained for vibrationally excited hydrogen molecules. ► The cross sections exhibit pronounced oscillatory structures. ► A comparison with the process involving the electron–hydrogen resonant ground state is discussed. - Abstract: Dissociative electron attachment cross sections (DEA) on vibrationally excited H 2 molecule taking place via the 2 Σ g + Rydberg-excited resonant state are studied using the local complex potential (LCP) model for resonant collisions. The cross sections are calculated for all initial vibrational levels (v i = 0–14) of the neutral molecule. In contrast to the previously noted dramatic increase in the DEA cross sections with increasing v i , when the process proceeds via the X 2 Σ u + shape resonance of H 2 , for the 2 Σ g + Rydberg resonance the cross sections increase only gradually up to v i = 3 and then decrease. Moreover, the cross sections for v i ⩾ 6 exhibit pronounced oscillatory structures. A discussion of the origin of the observed behavior of calculated cross sections is given. The DEA rate coefficients for all v i levels are also calculated in the 0.5–1000 eV temperature range.

  15. Hybridization of electron states in a step quantum well in a magnetic field

    International Nuclear Information System (INIS)

    Barseghyan, M.G.; Kirakosyan, A.A.

    2005-01-01

    The quantum states and energy levels of an electrion in a rectangular step quantum well in a magnetic field parallel to the plane of two-dimentional electron gas are investigated. It is shown that the joint effect of the magnetic field and confining potential of the quantum well results in redical change of the electron spectrum. The dependence of the electron energy levels on the quantum well parameters, magnetic field induction and projection of the wave-vector along the magnetic field induction are calculated. Numerical calculations are carried out for a AlAs/GaAlAs/GaAs/AlAs step quantum well

  16. State-specific transport properties of electronically excited Ar and C

    Science.gov (United States)

    Istomin, V. A.; Kustova, E. V.

    2018-05-01

    In the present study, a theoretical model of state-resolved transport properties in electronically excited atomic species developed earlier is applied to argon and carbon atomic species. It is shown that for Ar and C, similarly to the case of atomic nitrogen and oxygen, the Slater-like models can be applied to calculate diameters of electronically excited atoms. Using the Slater-like model it is shown that for half-filled N (2 px1py1pz1) and full-filled Ar (3 px2py2pz2) electronic shells the growth of atomic radius goes slowly compared to C (2 px1py1) and O (2 px2py1pz1). The effect of collision diameters on the transport properties of Ar and C is evaluated. The influence of accounted number of electronic levels on the transport coefficients is examined for the case of Boltzmann distributions over electronic energy levels. It is emphasized that in the temperature range 1000-14000 K, for Boltzmann-like distributions over electronic states the number of accounted electronic levels do not influence the transport coefficients. Contrary to this, for higher temperatures T > 14000 K this effect becomes of importance, especially for argon.

  17. Entanglement purification and concentration of electron-spin entangled states using quantum-dot spins in optical microcavities

    International Nuclear Information System (INIS)

    Wang Chuan; Zhang Yong; Jin Guangsheng

    2011-01-01

    We present an entanglement purification protocol and an entanglement concentration protocol for electron-spin entangled states, resorting to quantum-dot spin and optical-microcavity-coupled systems. The parity-check gates (PCGs) constructed by the cavity-spin-coupling system provide a different method for the entanglement purification of electron-spin entangled states. This protocol can efficiently purify an electron ensemble in a mixed entangled state. The PCGs can also concentrate electron-spin pairs in less-entangled pure states efficiently. The proposed methods are more flexible as only single-photon detection and single-electron detection are needed.

  18. Using Emotion as Information in Future-Oriented Cognition: Individual Differences in the Context of State Negative Affect

    Science.gov (United States)

    Marroquín, Brett; Boyle, Chloe C.; Nolen-Hoeksema, Susan; Stanton, Annette L.

    2016-01-01

    Predictions about the future are susceptible to mood-congruent influences of emotional state. However, recent work suggests individuals also differ in the degree to which they incorporate emotion into cognition. This study examined the role of such individual differences in the context of state negative emotion. We examined whether trait tendencies to use negative or positive emotion as information affect individuals' predictions of what will happen in the future (likelihood estimation) and how events will feel (affective forecasting), and whether trait influences depend on emotional state. Participants (N=119) reported on tendencies to use emotion as information (“following feelings”), underwent an emotion induction (negative versus neutral), and made likelihood estimates and affective forecasts for future events. Views of the future were predicted by both emotional state and individual differences in following feelings. Whereas following negative feelings affected most future-oriented cognition across emotional states, following positive feelings specifically buffered individuals' views of the future in the negative emotion condition, and specifically for positive future events, a category of future-event prediction especially important in psychological health. Individual differences may confer predisposition toward optimistic or pessimistic expectations of the future in the context of acute negative emotion, with implications for adaptive and maladaptive functioning. PMID:27041783

  19. Studies of isotopic effects in the excited electronic states of molecular systems

    International Nuclear Information System (INIS)

    1982-01-01

    Rare gas halogen (RGH) lasers serve as convenient tools for a range of photophysical processes which exhibit isotope effects. This document summarizes progress in the production of molecular systems in their electronic excited states with the aid of RGH lasers, and the various isotopic effects one can study under these conditions. We conclude that the basic physical mechanisms involved in the isotopically sensitive characteristics of excited molecular electronic states are sufficiently selective to be useful in both the detection and separation of many atomic materials

  20. Initial state dependence of low-energy electron emission in fast ion atom collisions

    International Nuclear Information System (INIS)

    Moshammer, R.; Schmitt, W.; Kollmus, H.; Ullrich, J.; Fainstein, P.D.; Hagmann, S.

    1999-06-01

    Single and multiple ionization of Neon and Argon atoms by 3.6 MeV/u Au 53+ impact has been explored in kinematically complete experiments. Doubly differential cross sections for low-energy electron emission have been obtained for defined charge state of the recoiling target ion and the receding projectile. Observed target specific structures in the electron continuum are attributable to the nodal structure of the initial bound state momentum distribution. The experimental data are in excellent accord with CDW-EIS single ionization calculations if multiple ionization is considered appropriately. (orig.)

  1. Surface Relaxation and Electronic States of Pt(111) Surface with Varying Slab Thickness

    International Nuclear Information System (INIS)

    Kaushal, Ashok K.; Mullick, Shanta; Ahluwalia, P. K.

    2011-01-01

    Surface relaxation and electronic DOS's of Pt(111) surface have been studied with varying slab thickness using ab-initio SIESTA method. We found the expansion in the top layer and contraction in the subsurface layers of Pt(111) surface. Our results match with the experimental results. Also observing electronic density of states we found that as we increase the thickness of slab, the PDOS of Pt(111) surface goes towards the bulk density of states and Fermi energy shifts towards the bulk fermi energy.

  2. Electronic structure of molecular Rydberg states of some small molecules and molecular ion

    International Nuclear Information System (INIS)

    Sun Biao; Li Jiaming

    1993-01-01

    Based on an independent-particle-approximation (i.e. the multiple scattering self-consistent-field theory), the electronic structures of Rydberg states of the small diatomic molecules H 2 , He 2 and the He 2 + molecular ion were studied. The principal quantum number of the first state of the Rydberg series is determined from a convention of the limit of the molecular electronic configuration. The dynamics of the excited molecules and molecular ion has been elucidated. The theoretical results are in fair agreement with the existing experimental measurements, thus they can serve as a reliable basis for future refined treatment such as the configuration interaction calculation

  3. Regional homogeneity of the resting-state brain activity correlates with individual intelligence.

    Science.gov (United States)

    Wang, Leiqiong; Song, Ming; Jiang, Tianzi; Zhang, Yunting; Yu, Chunshui

    2011-01-25

    Resting-state functional magnetic resonance imaging has confirmed that the strengths of the long distance functional connectivity between different brain areas are correlated with individual differences in intelligence. However, the association between the local connectivity within a specific brain region and intelligence during rest remains largely unknown. The aim of this study is to investigate the relationship between local connectivity and intelligence. Fifty-nine right-handed healthy adults participated in the study. The regional homogeneity (ReHo) was used to assess the strength of local connectivity. The associations between ReHo and full-scale intelligence quotient (FSIQ) scores were studied in a voxel-wise manner using partial correlation analysis controlling for age and sex. We found that the FSIQ scores were positively correlated with the ReHo values of the bilateral inferior parietal lobules, middle frontal, parahippocampal and inferior temporal gyri, the right thalamus, superior frontal and fusiform gyri, and the left superior parietal lobule. The main findings are consistent with the parieto-frontal integration theory (P-FIT) of intelligence, supporting the view that general intelligence involves multiple brain regions throughout the brain. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  4. Electronic structure and the mechanism of autoionization for doubly excited states

    International Nuclear Information System (INIS)

    Komninos, Y.; Makri, N.; Nicolaides, C.A.

    1986-01-01

    Apart from pure phenomenology, the rigorous and quantitative study of many-electron autoionizing states presents intriguing questions as regards their structure and dynamics. In this paper we present an analysis of such states within a state specific theory with application to five low-lying doubly excited states (DES) of He. The zeroth order description is multiconfigurational and is obtained numerically at the MCHF level. In this way, major radial and angular correlations are accounted for accurately, and reliable predictions can be made without the requirement of large computations. The additional localized correlation is obtained by optimizing variationally analytic virtual orbitals. (orig./WL)

  5. Gray matter deficits and altered resting-state connectivity in the superior temporal gyrus among individuals with problematic hypersexual behavior.

    Science.gov (United States)

    Seok, Ji-Woo; Sohn, Jin-Hun

    2018-04-01

    Neuroimaging studies on the characteristics of hypersexual disorder have been accumulating, yet alternations in brain structures and functional connectivity in individuals with problematic hypersexual behavior (PHB) has only recently been studied. This study aimed to investigate gray matter deficits and resting-state abnormalities in individuals with PHB using voxel-based morphometry and resting-state connectivity analysis. Seventeen individuals with PHB and 19 age-matched healthy controls participated in this study. Gray matter volume of the brain and resting-state connectivity were measured using 3T magnetic resonance imaging. Compared to healthy subjects, individuals with PHB had significant reductions in gray matter volume in the left superior temporal gyrus (STG) and right middle temporal gyrus. Individuals with PHB also exhibited a decrease in resting-state functional connectivity between the left STG and left precuneus and between the left STG and right caudate. The gray matter volume of the left STG and its resting-state functional connectivity with the right caudate both showed significant negative correlations with the severity of PHB. The findings suggest that structural deficits and resting-state functional impairments in the left STG might be linked to PHB and provide new insights into the underlying neural mechanisms of PHB. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Helical edge states and fractional quantum Hall effect in a graphene electron-hole bilayer.

    Science.gov (United States)

    Sanchez-Yamagishi, Javier D; Luo, Jason Y; Young, Andrea F; Hunt, Benjamin M; Watanabe, Kenji; Taniguchi, Takashi; Ashoori, Raymond C; Jarillo-Herrero, Pablo

    2017-02-01

    Helical 1D electronic systems are a promising route towards realizing circuits of topological quantum states that exhibit non-Abelian statistics. Here, we demonstrate a versatile platform to realize 1D systems made by combining quantum Hall (QH) edge states of opposite chiralities in a graphene electron-hole bilayer at moderate magnetic fields. Using this approach, we engineer helical 1D edge conductors where the counterpropagating modes are localized in separate electron and hole layers by a tunable electric field. These helical conductors exhibit strong non-local transport signals and suppressed backscattering due to the opposite spin polarizations of the counterpropagating modes. Unlike other approaches used for realizing helical states, the graphene electron-hole bilayer can be used to build new 1D systems incorporating fractional edge states. Indeed, we are able to tune the bilayer devices into a regime hosting fractional and integer edge states of opposite chiralities, paving the way towards 1D helical conductors with fractional quantum statistics.

  7. The reliability of assigning individuals to cognitive states using the Mini Mental-State Examination: a population-based prospective cohort study

    OpenAIRE

    Marioni, Riccardo E.; Chatfield, Mark; Brayne, Carol; Matthews, Fiona E.; Med Res Council

    2011-01-01

    Abstract Background Previous investigations of test re-test reliability of the Mini-Mental State Examination (MMSE) have used correlations and statistics such as Cronbach's α to assess consistency. In practice, the MMSE is usually used to group individuals into cognitive states. The reliability of this grouping (state based approach) has not been fully explored. Methods MMSE data were collected on a subset of 2,275 older participants (≥ 65 years) from the population-based Medical Research Cou...

  8. State laws prohibiting sales to minors and indoor use of electronic nicotine delivery systems--United States, November 2014.

    Science.gov (United States)

    Marynak, Kristy; Holmes, Carissa Baker; King, Brian A; Promoff, Gabbi; Bunnell, Rebecca; McAfee, Timothy

    2014-12-12

    Electronic nicotine delivery systems (ENDS), including electronic cigarettes (e-cigarettes) and other devices such as electronic hookahs, electronic cigars, and vape pens, are battery-powered devices capable of delivering aerosolized nicotine and additives to the user. Experimentation with and current use of e-cigarettes has risen sharply among youths and adults in the United States. Youth access to and use of ENDS is of particular concern given the potential adverse effects of nicotine on adolescent brain development. Additionally, ENDS use in public indoor areas might passively expose bystanders (e.g., children, pregnant women, and other nontobacco users) to nicotine and other potentially harmful constituents. ENDS use could have the potential to renormalize tobacco use and complicate enforcement of smoke-free policies. State governments can regulate the sales of ENDS and their use in indoor areas where nonusers might be involuntarily exposed to secondhand aerosol. To learn the current status of state laws regulating the sales and use of ENDS, CDC assessed state laws that prohibit ENDS sales to minors and laws that include ENDS use in conventional smoking prohibitions in indoor areas of private worksites, restaurants, and bars. Findings indicate that as of November 30, 2014, 40 states prohibited ENDS sales to minors, but only three states prohibited ENDS use in private worksites, restaurants, and bars. Of the 40 states that prohibited ENDS sales to minors, 21 did not prohibit ENDS use or conventional smoking in private worksites, restaurants, and bars. Three states had no statewide laws prohibiting ENDS sales to minors and no statewide laws prohibiting ENDS use or conventional smoking in private worksites, restaurants, and bars. According to the Surgeon General, ENDS have the potential for public health harm or public health benefit. The possibility of public health benefit from ENDS could arise only if 1) current smokers use these devices to switch completely

  9. Determination of the specific resistance of individual freestanding ZnO nanowires with the low energy electron point source microscope

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Dirk Henning; Beyer, Andre; Voelkel, Berthold; Goelzhaeuser, Armin [Physik Supramolekularer Systeme, Universitaet Bielefeld (Germany); Schlenker, Eva; Bakin, Andrey; Waag, Andreas [Institut fuer Halbleitertechnik, Technische Universitaet Braunschweig (Germany)

    2008-07-01

    A low energy electron point source (LEEPS) microscope is used to determine the electrical conductivity of individual freestanding ZnO nanowires in UHV. The nanowires were contacted with a manipulation tip and I-V curves were taken at different wire lengths. From those, the specific resistance was calculated and separated from the contact resistance. By comparing the specific resistances of ZnO nanowires with diameters between 1100 and 48 nm, a large surface contribution for the thin nanowires was found. A geometric model for separation between surface and bulk contributions is given. The results of electrical transport measurements on vapor phase grown ZnO nanowires are discussed, as well as the size dependence of the wire resistance.

  10. Electron transfer reactions induced by the triplet state of thiacarbocyanine dimers

    International Nuclear Information System (INIS)

    Chibisov, Alexander K.; Slavnova, Tatyana D.; Goerner, Helmut

    2004-01-01

    The photoinduced electron transfer between either cationic 5,5 ' -dichloro-3,3 ' ,9-triethylthiacarbocyanine (1) or a structurally similar anionic dye (2) and appropriate donors, e.g. ascorbic acid, and acceptors, e.g. methyl viologen, was studied by ns-laser photolysis. In aqueous solution the dyes in the ground state are present as an equilibrated mixture of dimers and monomers, whereas the triplet state is mainly populated from dimers. The triplet states of both dimers and monomers are quenched by electron donors or acceptors and the rate constant for quenching is generally 2-4 times higher for dimers than for monomers. The kinetics of triplet decay and radical formation and decay as a result of primary and secondary electron transfer were analyzed. While the one-electron reduced dimer decays due to back reactions, the one-electron oxidized dimer rapidly dissociates into the monomer and the monomeric dye radical. For the dimeric dye/donor/acceptor systems the primary photoinduced electron transfer occurs either from the donor or to the acceptor yielding the dimeric dye radicals. The one-electron reduced dimer can be efficiently oxidized by acceptors, e.g. the rate constant for reaction of the dimeric dye radical of 1 with methyl viologen (photoreductive pathway of sensitization) is 1.6x10 9 M -1 s -1 . The photooxidative pathway of sensitization is more complicated; after dissociation of the dimeric dye radical, the monomeric dye radical is reduced in a secondary electron transfer from ascorbic acid, e.g. with a rate constant of 1x10 9 M -1 s -1 for 2, yielding the monomer. On increasing the donor concentration the photooxidative pathway of sensitization is switched to a photoreductive one

  11. One-dimensional versus two-dimensional electronic states in vicinal surfaces

    International Nuclear Information System (INIS)

    Ortega, J E; Ruiz-Oses, M; Cordon, J; Mugarza, A; Kuntze, J; Schiller, F

    2005-01-01

    Vicinal surfaces with periodic arrays of steps are among the simplest lateral nanostructures. In particular, noble metal surfaces vicinal to the (1 1 1) plane are excellent test systems to explore the basic electronic properties in one-dimensional superlattices by means of angular photoemission. These surfaces are characterized by strong emissions from free-electron-like surface states that scatter at step edges. Thereby, the two-dimensional surface state displays superlattice band folding and, depending on the step lattice constant d, it splits into one-dimensional quantum well levels. Here we use high-resolution, angle-resolved photoemission to analyse surface states in a variety of samples, in trying to illustrate the changes in surface state bands as a function of d

  12. Brain state-dependence of electrically evoked potentials monitored with head-mounted electronics.

    Science.gov (United States)

    Richardson, Andrew G; Fetz, Eberhard E

    2012-11-01

    Inferring changes in brain connectivity is critical to studies of learning-related plasticity and stimulus-induced conditioning of neural circuits. In addition, monitoring spontaneous fluctuations in connectivity can provide insight into information processing during different brain states. Here, we quantified state-dependent connectivity changes throughout the 24-h sleep-wake cycle in freely behaving monkeys. A novel, head-mounted electronic device was used to electrically stimulate at one site and record evoked potentials at other sites. Electrically evoked potentials (EEPs) revealed the connectivity pattern between several cortical sites and the basal forebrain. We quantified state-dependent changes in the EEPs. Cortico-cortical EEP amplitude increased during slow-wave sleep, compared to wakefulness, while basal-cortical EEP amplitude decreased. The results demonstrate the utility of using portable electronics to document state-dependent connectivity changes in freely behaving primates.

  13. Electronically excited states of vitamin B12 and methylcobalamin: theoretical analysis of absorption, CD, and MCD data.

    Science.gov (United States)

    Solheim, Harald; Kornobis, Karina; Ruud, Kenneth; Kozlowski, Pawel M

    2011-02-03

    Linear and quadratic response time-dependent density functional theory (TD-DFT) has been applied to investigate absorption (Abs), circular dichroism (CD), and magnetic CD (MCD) spectra of cyanocobalamin (CNCbl) and methylcobalamin (MeCbl). Although electronically excited states of both cobalamins have been probed by applying different experimental techniques, their exact nature remains poorly understood from an electronic structure point of view. Recent theoretical studies have revealed a lot of relevant information about their properties but also left some unresolved issues related to the nature of individual transitions. In this contribution, not only Abs but also CD and MCD spectra of both cobalamins were computed for direct comparison with experiment. The results were evaluated with respect to the choice of exchange-correlation functional, basis set, and the environment (gas phase or solvent) used in the calculation. Taking into account the complexity of the CNCbl and MeCbl systems, reliable agreement between theory and experiment was achieved based on calculations employing the BP86 functional, particularly for the low-energy α/β bands. This spectral range has been traditionally interpreted as a vibrational progression associated with a single electronic excitation, but according to the present analysis for both cobalamins, these bands are best interpreted as consisting of multiple electronic transitions.

  14. Low-Lying Electronic States of AlZn Calculated by MRCI+Q Method

    Science.gov (United States)

    Zhang, Shudong; Wang, Mingxu; Wang, Zifan; Hu, Kun; Dong, Jingping

    2017-07-01

    Some low-lying electronic states of AlZn have been studied by the ab initio calculation method of multireference configuration interaction (MRCI). The complete potential energy curves (PECs) of the three lowest doublet states (X2Π, A2Σ+, and B2Π) and the two lowest quartet states (a4Σ- and b4Π) are computed in the range of R = 0.1-0.9 nm and these states are correlated to three dissociation limits, X2Π and A2Σ+ to Zn(4s2,1S) + Al(3s23p1,2P), a4Σ- and b4Π to Zn(4s2,1S) + Al(3s13p2,4P), and B2Π to Zn(4s14p1,3P) + Al(3s23p1,2P). The calculated PECs indicate that the A2Σ+ state has a very shallow potential well and the other states show significant binding-state characteristics. The equilibrium internuclear distances Re, dissociation energies De, and term energies Te for the electronic excited states were obtained. All the possible vibrational levels, rotational constants, and spectral constants for the four bound states were computed by solving the radial Schrödinger equation of nuclear motion with the Level8.0 program provided by Le Roy.

  15. Multi-Center Electronic Structure Calculations for Plasma Equation of State

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B G; Johnson, D D; Alam, A

    2010-12-14

    We report on an approach for computing electronic structure utilizing solid-state multi-center scattering techniques, but generalized to finite temperatures to model plasmas. This approach has the advantage of handling mixtures at a fundamental level without the imposition of ad hoc continuum lowering models, and incorporates bonding and charge exchange, as well as multi-center effects in the calculation of the continuum density of states.

  16. Atypical extended electronic states in an infinite Vicsek fractal: An exact result

    International Nuclear Information System (INIS)

    Chakrabarti, A.; Bhattacharyya, B.

    1996-01-01

    We present a class of extended electronic wave functions on a Vicsek fractal. The transmittivity of arbitrarily large fractal lattices corresponding to these particular extended-state eigenvalues exhibits a power-law decay with increasing system size. The eigenvalues corresponding to the above extended states as well as the scaling law for the transmittivity have been exactly calculated using a real-space renormalization-group method. copyright 1996 The American Physical Society

  17. High-frequency two-electron photoionization cross section of triplet states

    International Nuclear Information System (INIS)

    Krivec, R.; Amusia, M.Ya.; Mandelzweig, V.B.

    2003-01-01

    Using high precision wave functions describing the triplet ground and excited 3 S states of the He atom and heliumlike ions, the cross sections of single- and double-electron photoionization are calculated. The dependence of the ratio R of the double and single ionization cross sections on the nuclear charge Z and the principal quantum number of excitation n is studied. The results obtained are compared to those for previously studied singlet states

  18. Many electron variational ground state of the two dimensional Anderson lattice

    International Nuclear Information System (INIS)

    Zhou, Y.; Bowen, S.P.; Mancini, J.D.

    1991-02-01

    A variational upper bound of the ground state energy of two dimensional finite Anderson lattices is determined as a function of lattice size (up to 16 x 16). Two different sets of many-electron basis vectors are used to determine the ground state for all values of the coulomb integral U. This variational scheme has been successfully tested for one dimensional models and should give good estimates in two dimensions

  19. Steady states of a diode with counterstreaming electron and positron beams

    Energy Technology Data Exchange (ETDEWEB)

    Ender, A. Ya.; Kuznetsov, V. I., E-mail: victor.kuznetsov@mail.ioffe.ru; Gruzdev, A. A. [Russian Academy of Sciences, Ioffe Institute (Russian Federation)

    2016-10-15

    Steady states of a plasma layer with counterstreaming beams of oppositely charged particles moving without collisions in a self-consistent electric field are analyzed. The study is aimed at clarifying the mechanism of generation and reconstruction of pulsar radiation. Such a layer also models the processes occurring in Knudsen plasma diodes with counterstreaming electron and ion beams. The steady-state solutions are exhaustively classified. The existence of several solutions at the same external parameters is established.

  20. Generation of human auditory steady-state responses (SSRs). II: Addition of responses to individual stimuli.

    Science.gov (United States)

    Santarelli, R; Maurizi, M; Conti, G; Ottaviani, F; Paludetti, G; Pettorossi, V E

    1995-03-01

    In order to investigate the generation of the 40 Hz steady-state response (SSR), auditory potentials evoked by clicks were recorded in 16 healthy subjects in two stimulating conditions. Firstly, repetition rates of 7.9 and 40 Hz were used to obtain individual middle latency responses (MLRs) and 40 Hz-SSRs, respectively. In the second condition, eight click trains were presented at a 40 Hz repetition rate and an inter-train interval of 126 ms. We extracted from the whole train response: (1) the response-segment taking place after the last click of the train (last click response, LCR), (2) a modified LCR (mLCR) obtained by clearing the LCR from the amplitude enhancement due to the overlapping of the responses to the clicks preceding the last within the stimulus train. In comparison to MLRs, the most relevant feature of the evoked activity following the last click of the train (LCRs, mLCRs) was the appearance in the 50-110 ms latency range of one (in 11 subjects) or two (in 2 subjects) additional positive-negative deflections having the same periodicity as that of MLR waves. The grand average (GA) of the 40 Hz-SSRs was compared with three predictions synthesized by superimposing: (1) the GA of MLRs, (2) the GA of LCRs, (3) the GA of mLCRs. Both the MLR and mLCR predictions reproduced the recorded signal in amplitude while the LCR prediction amplitude resulted almost twice that of the 40 Hz-SSR. With regard to the phase, the MLR, LCR and mLCR closely predicted the recorded signal. Our findings confirm the effectiveness of the linear addition mechanism in the generation of the 40 Hz-SSR. However the responses to individual stimuli within the 40 Hz-SSR differ from MLRs because of additional periodic activity. These results suggest that phenomena related to the resonant frequency of the activated system may play a role in the mechanisms which interact to generate the 40 Hz-SSR.

  1. Physical reason for quantum behaviour of the electron and stability of the main state of the hydrogen atom

    International Nuclear Information System (INIS)

    Rangelov, J.M.

    1986-01-01

    An electron model is proposed explaining the physical reasons for its nonrelativistic quantum-mechanical behaviour, the origin of its own mechanical and magnetic momentum and field energy. As an example the main electron state in hydrogen atom is obtained

  2. Spectroscopic Diagnosis of Excited-State Aromaticity: Capturing Electronic Structures and Conformations upon Aromaticity Reversal.

    Science.gov (United States)

    Oh, Juwon; Sung, Young Mo; Hong, Yongseok; Kim, Dongho

    2018-03-06

    Aromaticity, the special energetic stability derived from cyclic [4 n + 2]π-conjugated electronic structures, has been the topic of intense interest in chemistry because it plays a critical role in rationalizing molecular stability, reactivity, and physical/chemical properties. Recently, the pioneering work by Colin Baird on aromaticity reversal, postulating that aromatic (antiaromatic) character in the ground state reverses to antiaromatic (aromatic) character in the lowest excited triplet state, has attracted much scientific attention. The completely reversed aromaticity in the excited state provides direct insight into understanding the photophysical/chemical properties of photoactive materials. In turn, the application of aromatic molecules to photoactive materials has led to numerous studies revealing this aromaticity reversal. However, most studies of excited-state aromaticity have been based on the theoretical point of view. The experimental evaluation of aromaticity in the excited state is still challenging and strenuous because the assessment of (anti)aromaticity with conventional magnetic, energetic, and geometric indices is difficult in the excited state, which practically restricts the extension and application of the concept of excited-state aromaticity. Time-resolved optical spectroscopies can provide a new and alternative avenue to evaluate excited-state aromaticity experimentally while observing changes in the molecular features in the excited states. Time-resolved optical spectroscopies take advantage of ultrafast laser pulses to achieve high time resolution, making them suitable for monitoring ultrafast changes in the excited states of molecular systems. This can provide valuable information for understanding the aromaticity reversal. This Account presents recent breakthroughs in the experimental assessment of excited-state aromaticity and the verification of aromaticity reversal with time-resolved optical spectroscopic measurements. To

  3. Soft x-ray spectroscopy for probing electronic and chemical states of battery materials

    International Nuclear Information System (INIS)

    Yang Wanli; Qiao Ruimin

    2016-01-01

    The formidable challenge of developing high-performance battery system stems from the complication of battery operations, both mechanically and electronically. In the electrodes and at the electrode–electrolyte interfaces, chemical reactions take place with evolving electron states. In addition to the extensive studies of material synthesis, electrochemical, structural, and mechanical properties, soft x-ray spectroscopy provides unique opportunities for revealing the critical electron states in batteries. This review discusses some of the recent soft x-ray spectroscopic results on battery binder, transition-metal based positive electrodes, and the solid-electrolyte-interphase. By virtue of soft x-ray’s sensitivity to electron states, the electronic property, the redox during electrochemical operations, and the chemical species of the interphases could be fingerprinted by soft x-ray spectroscopy. Understanding and innovating battery technologies need a multimodal approach, and soft x-ray spectroscopy is one of the incisive tools to probe the chemical and physical evolutions in batteries. (topical review)

  4. Towards native-state imaging in biological context in the electron microscope

    Science.gov (United States)

    Weston, Anne E.; Armer, Hannah E. J.

    2009-01-01

    Modern cell biology is reliant on light and fluorescence microscopy for analysis of cells, tissues and protein localisation. However, these powerful techniques are ultimately limited in resolution by the wavelength of light. Electron microscopes offer much greater resolution due to the shorter effective wavelength of electrons, allowing direct imaging of sub-cellular architecture. The harsh environment of the electron microscope chamber and the properties of the electron beam have led to complex chemical and mechanical preparation techniques, which distance biological samples from their native state and complicate data interpretation. Here we describe recent advances in sample preparation and instrumentation, which push the boundaries of high-resolution imaging. Cryopreparation, cryoelectron microscopy and environmental scanning electron microscopy strive to image samples in near native state. Advances in correlative microscopy and markers enable high-resolution localisation of proteins. Innovation in microscope design has pushed the boundaries of resolution to atomic scale, whilst automatic acquisition of high-resolution electron microscopy data through large volumes is finally able to place ultrastructure in biological context. PMID:19916039

  5. Abortion in Turkey: a matter of state, family or individual decision.

    Science.gov (United States)

    Gürsoy, A

    1996-02-01

    This paper gives a historical, international and cultural outlook on the debate related to the 1982 legalization of abortion in the modern democratic republic of Turkey. A belief that the country is under-populated and subsequent pro-natalist concerns of the turn of the century seem to have strongly influenced the legal prohibition of abortion. The paper first discusses the widespread social practice and the permissive attitudes towards abortion in the late Ottoman Empire and in contemporary Turkey. The contrast between the above social situation and until recently the strict, non-permissive religious and secular attitudes are presented with a discussion of the effects of the westernization and secularization processes in the late Ottoman Empire. Moral concerns and judgements regarding abortion seem to have penetrated Ottoman society as part of the above processes beginning in the nineteenth century. The present day official religious interpretations seem to conform with the more conservative Islamic schools of thought rather than the more liberal Islamic interpretations. Furthermore, the 1982 laws which legalize abortion until the eight week of pregnancy consider family planning to be a family issue and bring the restriction of making married women have their husband's permission before preceding with abortion. As such, the present legal platform opens to question the rationales and population control motives behind the law and the importance of who it is that can make the decision to proceed with abortion. Thus, in the last 70 years a historical and ideological progression can be discerned in the line of assuming first the state and then the family to have decision making legitimacy as regards reproductive choices. Today, the platform of radical discussion has shifted to evaluating the importance of individual women in making this reproductive choice. In this context, in conclusion, the paper discussed the rationale and the logic behind and the implications for

  6. Peculiarities of resonant tunneling of electrons through the triply degenerate state of a quantum well

    International Nuclear Information System (INIS)

    Jermakov, V.M.

    1997-01-01

    In the case of low transparency of barriers, tunneling of electrons through a double barrier system with account their Coulomb interaction in the inter barrier space (quantum well) is considered. The quantum state of the well is supposed to be triply degenerated. It was shown that the dependence of quantum well accupation on the applied bias has a step like character at low temperatures, and there is a threshold value in the region of small applied bias. These properties can be explained by splitting of states in the well due to the electron interaction. The considered system also has bistability properties. This is due to the possibility for electrons to occupy upper levels in the well while lower levels remain empty. Charge fluctuations in the well are also discussed

  7. Fine structures of atomic excited states: precision atomic spectroscopy and electron-ion collision process

    International Nuclear Information System (INIS)

    Gao Xiang; Cheng Cheng; Li Jiaming

    2011-01-01

    Scientific research fields for future energies such as inertial confinement fusion researches and astrophysics studies especially with satellite observatories advance into stages of precision physics. The relevant atomic data are not only enormous but also of accuracy according to requirements, especially for both energy levels and the collision data. The fine structure of high excited states of atoms and ions can be measured by precision spectroscopy. Such precision measurements can provide not only knowledge about detailed dynamics of electron-ion interactions but also a bench mark examination of the accuracy of electron-ion collision data, especially incorporating theoretical computations. We illustrate that by using theoretical calculation methods which can treat the bound states and the adjacent continua on equal footing. The precision spectroscopic measurements of excited fine structures can be served as stringent tests of electron-ion collision data. (authors)

  8. Modeling and Simulation of DC Power Electronics Systems Using Harmonic State Space (HSS) Method

    DEFF Research Database (Denmark)

    Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth

    2015-01-01

    based on the state-space averaging and generalized averaging, these also have limitations to show the same results as with the non-linear time domain simulations. This paper presents a modeling and simulation method for a large dc power electronic system by using Harmonic State Space (HSS) modeling......For the efficiency and simplicity of electric systems, the dc based power electronics systems are widely used in variety applications such as electric vehicles, ships, aircrafts and also in homes. In these systems, there could be a number of dynamic interactions between loads and other dc-dc....... Through this method, the required computation time and CPU memory for large dc power electronics systems can be reduced. Besides, the achieved results show the same results as with the non-linear time domain simulation, but with the faster simulation time which is beneficial in a large network....

  9. Carrier emission from the electronic states of self-assembled indium arsenide quantum dots

    International Nuclear Information System (INIS)

    Lin, S.W.; Song, A.M.; Missous, M.; Hawkins, I.D; Hamilton, B.; Engstroem, O.; Peaker, A.R.

    2006-01-01

    We have used the new technique of high resolution (Laplace) transient spectroscopy to examine the electronic states of ensembles of self-assembled quantum dots of InAs in a GaAs matrix. These have been produced by solid source MBE. We have monitored the s and p state occupancies as a function of time under thermal excitation over a range of temperatures after electrons have been captured by the quantum dots with different Fermi level positions. This can provide more information about the interaction of the dots with the host matrix than is possible with optical techniques and gives new fundamental insights into how such dots may operate in electronic devices such as memory and sensors. The increase in resolution of Laplace transient spectroscopy over conventional experiments reveals quite specific rates of carrier loss which we attribute to tunnelling at low temperatures and a combination of thermal emission and tunnelling as the temperature is increased

  10. Theory of life time measurements with the scanning electron microscope: steady state

    NARCIS (Netherlands)

    Berz, F.; Kuiken, H.K.

    1976-01-01

    A theoretical steady state analysis is given of the scanning electron microscope method of measuring bulk life time in diodes, where the plane of the junction is perpendicular to the surface. The current in the junction is obtained as a function of the beam power, the beam penetration into the

  11. Managing Selection for Electronic Resources: Kent State University Develops a New System to Automate Selection

    Science.gov (United States)

    Downey, Kay

    2012-01-01

    Kent State University has developed a centralized system that manages the communication and work related to the review and selection of commercially available electronic resources. It is an automated system that tracks the review process, provides selectors with price and trial information, and compiles reviewers' feedback about the resource. It…

  12. Implications of electron attachment to highly-excited states in pulsed-power discharges

    International Nuclear Information System (INIS)

    Pinnaduwage, L.A.; Univ. of Tennessee, Knoxville, TN

    1997-01-01

    The author points out the possible implications of electron attachment to highly-excited states of molecules in two pulsed power technologies. One involves the pulsed H 2 discharges used for the generation of H ion beams for magnetic fusion energy and particle accelerators. The other is the power modulated plasma discharges used for material processing

  13. Nanoscale probing of bandgap states on oxide particles using electron energy-loss spectroscopy.

    Science.gov (United States)

    Liu, Qianlang; March, Katia; Crozier, Peter A

    2017-07-01

    Surface and near-surface electronic states were probed with nanometer spatial resolution in MgO and TiO 2 anatase nanoparticles using ultra-high energy resolution electron energy-loss spectroscopy (EELS) coupled to a scanning transmission electron microscope (STEM). This combination allows the surface electronic structure determined with spectroscopy to be correlated with nanoparticle size, morphology, facet etc. By acquiring the spectra in aloof beam mode, radiation damage to the surface can be significantly reduced while maintaining the nanometer spatial resolution. MgO and TiO 2 showed very different bandgap features associated with the surface/sub-surface layer of the nanoparticles. Spectral simulations based on dielectric theory and density of states models showed that a plateau feature found in the pre-bandgap region in the spectra from (100) surfaces of 60nm MgO nanocubes is consistent with a thin hydroxide surface layer. The spectroscopy shows that this hydroxide species gives rise to a broad filled surface state at 1.1eV above the MgO valence band. At the surfaces of TiO 2 nanoparticles, pronounced peaks were observed in the bandgap region, which could not be well fitted to defect states. In this case, the high refractive index and large particle size may make Cherenkov or guided light modes the likely causes of the peaks. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Jumping magneto-electric states of electrons in semiconductor multiple quantum wells

    International Nuclear Information System (INIS)

    Pfeffer, Pawel; Zawadzki, Wlodek

    2011-01-01

    Orbital and spin electron states in semiconductor multiple quantum wells in the presence of an external magnetic field transverse to the growth direction are considered. Rectangular wells of GaAs/GaAlAs and InAs/AlSb are taken as examples. It is shown that, in addition to magneto-electric states known from one-well systems, there appear magneto-electric states having a much stronger dependence of energies on a magnetic field and exhibiting an interesting anti-crossing behavior. The origin of these states is investigated and it is shown that the strong field dependence of the energies is related to an unusual 'jumping' behavior of their wavefunctions between quantum wells as the field increases. The ways of investigating the jumping states by means of interband magneto-luminescence transitions or intraband cyclotron-like transitions are considered and it is demonstrated that the jumping states can be observed. The spin g factors of electrons in the jumping states are calculated using the real values of the spin–orbit interaction and bands' nonparabolicity for the semiconductors in question. It is demonstrated that the jumping states offer a wide variety of the spin g factors

  15. Electron Elevator: Excitations across the Band Gap via a Dynamical Gap State.

    Science.gov (United States)

    Lim, A; Foulkes, W M C; Horsfield, A P; Mason, D R; Schleife, A; Draeger, E W; Correa, A A

    2016-01-29

    We use time-dependent density functional theory to study self-irradiated Si. We calculate the electronic stopping power of Si in Si by evaluating the energy transferred to the electrons per unit path length by an ion of kinetic energy from 1 eV to 100 keV moving through the host. Electronic stopping is found to be significant below the threshold velocity normally identified with transitions across the band gap. A structured crossover at low velocity exists in place of a hard threshold. An analysis of the time dependence of the transition rates using coupled linear rate equations enables one of the excitation mechanisms to be clearly identified: a defect state induced in the gap by the moving ion acts like an elevator and carries electrons across the band gap.

  16. Electron-photon angular correlation measurements for the 2 1P state of helium

    International Nuclear Information System (INIS)

    Slevin, J.; Porter, H.Q.; Eminyan, M.; Defrance, A.; Vassilev, G.

    1980-01-01

    Electron-photon angular correlations have been measured by detecting in delayed coincidence, electrons inelastically scattered from helium and photons emitted in decays from the 2 1 P state at incident electron energies of 60 and 80 eV. Analysis of the data yields values for the ratio lambda of the differential cross sections for magnetic sublevel excitations and the phase difference X between the corresponding probability amplitudes. The measurements extend over the angular range 10-120 0 of electron scattering angles. The present data are in good agreement with the experimental results of Hollywood et al, (J. Phys. B.; 12: 819 (1979)), and show a marked discrepancy at large scattering angles with the recent data of Steph and Golde. (Phys. Rev.; A in press (1980)). The experimental results are compared with some recent theories. (author)

  17. Solid state effects on the electronic structure of H2OEP.

    Science.gov (United States)

    Marsili, M; Umari, P; Di Santo, G; Caputo, M; Panighel, M; Goldoni, A; Kumar, M; Pedio, M

    2014-12-28

    We present the results of a joint experimental and theoretical investigation concerning the effect of crystal packing on the electronic properties of the H2OEP molecule. Thin films, deposited in ultra high vacuum on metal surfaces, are investigated by combining valence band photoemission, inverse photoemission, and X-ray absorption spectroscopy. The spectra of the films are compared, when possible, with those measured in the gas phase. Once many-body effects are included in the calculations through the GW method, the electronic structure of H2OEP in the film and gas phase are accurately reproduced for both valence and conduction states. Upon going from an isolated molecule to the film phase, the electronic gap shrinks significantly and the lowest unoccupied molecular orbital (LUMO) and LUMO + 1 degeneracy is removed. The calculations show that the reduction of the transport gap in the film is entirely addressable to the enhancement of the electronic screening.

  18. The Effects of State Medicaid Expansion on Low-Income Individuals' Access to Health Care: Multilevel Modeling.

    Science.gov (United States)

    Choi, Sunha; Lee, Sungkyu; Matejkowski, Jason

    2018-06-01

    This study aimed to examine how states' Medicaid expansion affected insurance status and access to health care among low-income expansion state residents in 2015, the second year of the expansion. Data from the 2012 and 2015 Behavioral Risk Factor Surveillance System were linked to state-level data. A nationally representative sample of 544,307 adults (ages 26-64 years) from 50 states and Washington, DC were analyzed using multilevel modeling. The results indicate substantial increases in health care access between 2012 and 2015 among low-income adults in Medicaid expansion states. The final conditional multilevel models with low-income adults who had income at or below 138% of the poverty line indicate that, after controlling for individual- and state-level covariates, those who resided in the Medicaid expansion states were more likely to have health insurance (OR = 1.97, P income residents in non-expansion states in 2015. Moreover, the significant interaction terms indicate that adults living in non-expansion states with income below 100% of the poverty line are the most vulnerable compared with their counterparts in expansion states and with those with income between 100%-138% of the poverty line. This study demonstrates that state-level Medicaid expansion improved health care access among low-income US residents. However, residents with income below 100% of the poverty line in non-expansion states were disproportionately negatively affected by states' decision to not expand Medicaid coverage.

  19. State of the art in atomic resolution off-axis electron holography

    International Nuclear Information System (INIS)

    Linck, Martin; Freitag, Bert; Kujawa, Stephan; Lehmann, Michael; Niermann, Tore

    2012-01-01

    As proposed by Hannes Lichte, to resolve structure–property relations not only the question “Which atom is where?” but also the question “Which fields are around?” has to be answered. High-resolution off-axis electron holography opens up an access to these key questions in that it allows accessing the complete exit-wave of the object provided within the information limit of the microscope, i.e. amplitude and phase including atomic details such as position and species, and moreover, information about large area electric potentials and magnetic fields, which a conventional transmission electron microscope is blind for—also when using a Cs-corrector. For an excellent object exit-wave reconstruction, special care has to be taken on the hologram quality, i.e. interference fringe contrast and electron dose. Severe restrictions are given to signal resolution by the limited brightness of the electron source. Utilizing a new high-brightness Schottky field electron emitter in a state-of-the-art transmission electron microscope operated at 300 kV, the phase signal resolution at atomic resolution can significantly be enhanced. An improvement by at least a factor of 2.88 compared to the most recently reported single hologram at atomic resolution is found. To proof the applicability of this setup to real materials science problems, a grain boundary of gold has been investigated holographically. -- Highlights: ► Impact of the brightness on the reconstructed signal in electron holography. ► Factor 2.8 gain in signal quality by setup with a high brightness electron gun. ► Investigation of a grain boundary in gold with a state-of-the-art holography setup. ► A-posteriori aberration fine-tuning for true one Angstrom resolution in the object wave. ► Mistilt analysis on the atomic scale by numerical wave optics.

  20. Calculation of Vibrational and Electronic Excited-State Absorption Spectra of Arsenic-Water Complexes Using Density Functional Theory

    Science.gov (United States)

    2016-06-03

    Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6390--16-9681 Calculation of Vibrational and Electronic Excited -State Absorption Spectra...NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Calculation of Vibrational and Electronic Excited -State Absorption Spectra of Arsenic-Water Complexes Using...Unclassified Unlimited Unclassified Unlimited 59 Samuel G. Lambrakos (202) 767-2601 Calculations are presented of vibrational and electronic excited -state

  1. The electronic structure of VO in its ground and electronically excited states: A combined matrix isolation and quantum chemical (MRCI) study

    International Nuclear Information System (INIS)

    Hübner, Olaf; Hornung, Julius; Himmel, Hans-Jörg

    2015-01-01

    The electronic ground and excited states of the vanadium monoxide (VO) molecule were studied in detail. Electronic absorption spectra for the molecule isolated in Ne matrices complement the previous gas-phase spectra. A thorough quantum chemical (multi-reference configuration interaction) study essentially confirms the assignment and characterization of the electronic excitations observed for VO in the gas-phase and in Ne matrices and allows the clarification of open issues. It provides a complete overview over the electronically excited states up to about 3 eV of this archetypical compound

  2. An all-silicon laser by coupling between electronic localized states and defect states of photonic crystal

    Energy Technology Data Exchange (ETDEWEB)

    Huang Weiqi, E-mail: WQHuang2001@yahoo.com [Institute of Nanophotonic Physics, Key Laboratory of Photoelectron Technology and Application, Guizhou University, Guiyang 550025 (China); Huang Zhongmei; Miao Xinjiang; Cai Chenlan; Liu Jiaxin; Lue Quan [Institute of Nanophotonic Physics, Key Laboratory of Photoelectron Technology and Application, Guizhou University, Guiyang 550025 (China); Liu Shirong, E-mail: Shirong@yahoo.com [State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550003 (China); Qin Chaojian [State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550003 (China)

    2012-01-15

    In a nano-laser of Si quantum dots (QD), the smaller QD fabricated by nanosecond pulse laser can form the pumping level tuned by the quantum confinement (QC) effect. Coupling between the active centers formed by localized states of surface bonds and the two-dimensional (2D) photonic crystal is used to select model in the nano-laser. The experimental demonstration is reported in which the peaks of stimulated emission at about 600 nm and 700 nm were observed on the Si QD prepared in oxygen after annealing which improves the stimulated emission. It is interesting to make a comparison between the localized electronic states in gap due to defect formed by surface bonds and the localized photonic states in gap of photonic band due to defect of 2D photonic crystal.

  3. Antibonding intermediate state in the theory of vibrational excitation of diatomic molecules by slow electrons

    International Nuclear Information System (INIS)

    Kazanskii, A.K.

    1982-01-01

    An exactly solvable model is constructed for the description of the processes that take place when a slow electron collides with a diatomic molecule (vibrational excitation, associative detachment, and dissociative attachment). As a particular model of the variant, the case of an antibonding (virtual) state of an intermediate state is considered, and a term of this state is parametrized in a very simple manner. The vibrational excitation and dissociative attachment are calculated for a system corresponding to the HCl molecule. The results are in good qualitative agreement with experiment

  4. Electron-tunneling observation of localized excited states in superconducting manganese-doped lead

    International Nuclear Information System (INIS)

    Tsang, J.; Ginsberg, D.M.

    1980-01-01

    We have made electron-tunneling measurements on a dilute, superconducting lead-manganese alloy. A well-defined structure was observed in the ac-conductance--voltage curves, indicating excited states within the BCS energy gap. These states were partially accounted for by Shiba theory when spin-dependent s-, p-, and d-wave scattering were included. The phase shifts used in doing that were the results of band calculations. The experimental data also show the existence of a broad background density of states in the energy gap, which cannot be accounted for by the theory

  5. Multi-state models for clustered duration data: an application to workplace effects on individual sickness absenteeism

    OpenAIRE

    Lindeboom, Maarten; Kerkhofs, Marcel

    1998-01-01

    In this paper we specify and estimate three state duration models of work, sickness and exit from the job to explain individual absenteeism behaviour of primary school teachers. There is a large variation of sickness absenteeism records across schools and absenteeism records of workers within a school appear to be related. This clustering of individual absenteeism data may to a large extend be caused by workplace effects. Since it will be difficult to fully capture workplace effects with obse...

  6. Influence of metallic surface states on electron affinity of epitaxial AlN films

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Monu; Krishna, Shibin; Aggarwal, Neha [Advanced Materials and Devices Division, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Marg, New Delhi110012 (India); Academy of Scientific and Innovative Research (AcSIR), CSIR-NPL Campus, Dr. K.S. Krishnan Marg, New Delhi 110012 (India); Gupta, Govind, E-mail: govind@nplindia.org [Advanced Materials and Devices Division, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Marg, New Delhi110012 (India); Academy of Scientific and Innovative Research (AcSIR), CSIR-NPL Campus, Dr. K.S. Krishnan Marg, New Delhi 110012 (India)

    2017-06-15

    The present article investigates surface metallic states induced alteration in the electron affinity of epitaxial AlN films. AlN films grown by plasma-assisted molecular beam epitaxy system with (30% and 16%) and without metallic aluminium on the surface were probed via photoemission spectroscopic measurements. An in-depth analysis exploring the influence of metallic aluminium and native oxide on the electronic structure of the films is performed. It was observed that the metallic states pinned the Fermi Level (FL) near valence band edge and lead to the reduction of electron affinity (EA). These metallic states initiated charge transfer and induced changes in surface and interface dipoles strength. Therefore, the EA of the films varied between 0.6–1.0 eV due to the variation in contribution of metallic states and native oxide. However, the surface barrier height (SBH) increased (4.2–3.5 eV) adversely due to the availability of donor-like surface states in metallic aluminium rich films.

  7. Rotational and fine structure of open-shell molecules in nearly degenerate electronic states

    Science.gov (United States)

    Liu, Jinjun

    2018-03-01

    An effective Hamiltonian without symmetry restriction has been developed to model the rotational and fine structure of two nearly degenerate electronic states of an open-shell molecule. In addition to the rotational Hamiltonian for an asymmetric top, this spectroscopic model includes the energy separation between the two states due to difference potential and zero-point energy difference, as well as the spin-orbit (SO), Coriolis, and electron spin-molecular rotation (SR) interactions. Hamiltonian matrices are computed using orbitally and fully symmetrized case (a) and case (b) basis sets. Intensity formulae and selection rules for rotational transitions between a pair of nearly degenerate states and a nondegenerate state have also been derived using all four basis sets. It is demonstrated using real examples of free radicals that the fine structure of a single electronic state can be simulated with either a SR tensor or a combination of SO and Coriolis constants. The related molecular constants can be determined precisely only when all interacting levels are simulated simultaneously. The present study suggests that analysis of rotational and fine structure can provide quantitative insights into vibronic interactions and related effects.

  8. Regimes of radiative and nonradiative transitions in transport through an electronic system in a photon cavity reaching a steady state

    Science.gov (United States)

    Gudmundsson, Vidar; Jonsson, Thorsteinn H.; Bernodusson, Maria Laura; Abdullah, Nzar Rauf; Sitek, Anna; Goan, Hsi-Sheng; Tang, Chi-Shung; Manolescu, Andrei

    2017-01-01

    We analyze how a multilevel many-electron system in a photon cavity approaches the steady state when coupled to external leads. When a plunger gate is used to lower cavity photon dressed one- and two-electron states below the bias window defined by the external leads, we can identify one regime with nonradiative transitions dominating the electron transport, and another regime with radiative transitions. Both transitions trap the electrons in the states below the bias bringing the system into a steady state. The order of the two regimes and their relative strength depends on the location of the bias window in the energy spectrum of the system and the initial conditions.

  9. Vibrational states in deformed nuclei. Chaos, order and individual nature of nuclei

    International Nuclear Information System (INIS)

    Soloviev, V.G.

    1993-01-01

    General properties of the vibrational states in doubly-even well-deformed are formulated. The large many-quasiparticle components of the wave functions of the neutron resonance state are responsible for enhance E1- and M1-transitions rates from the neutron resonances states to the levels lying 1-2 MeV below them. 44 refs.; 4 tabs

  10. Electronic health record-based patient identification and individualized mailed outreach for primary cardiovascular disease prevention: a cluster randomized trial.

    Science.gov (United States)

    Persell, Stephen D; Lloyd-Jones, Donald M; Friesema, Elisha M; Cooper, Andrew J; Baker, David W

    2013-04-01

    Many individuals at higher risk for cardiovascular disease (CVD) do not receive recommended treatments. Prior interventions using personalized risk information to promote prevention did not test clinic-wide effectiveness. To perform a 9-month cluster-randomized trial, comparing a strategy of electronic health record-based identification of patients with increased CVD risk and individualized mailed outreach to usual care. Patients of participating physicians with a Framingham Risk Score of at least 5 %, low-density lipoprotein (LDL)-cholesterol level above guideline threshold for drug treatment, and not prescribed a lipid-lowering medication were included in the intention-to-treat analysis. Patients of physicians randomized to the intervention group were mailed individualized CVD risk messages that described benefits of using a statin (and controlling hypertension or quitting smoking when relevant). The primary outcome was occurrence of a LDL-cholesterol level, repeated in routine practice, that was at least 30 mg/dl lower than prior. A secondary outcome was lipid-lowering drug prescribing. Clinicaltrials.gov identifier: NCT01286311. Fourteen physicians with 218 patients were randomized to intervention, and 15 physicians with 217 patients to control. The mean patient age was 60.7 years and 77% were male. There was no difference in the primary outcome (11.0 % vs. 11.1 %, OR 0.99, 95 % CI 0.56-1.74, P = 0.96), but intervention group patients were twice as likely to receive a prescription for lipid-lowering medication (11.9 %, vs. 6.0 %, OR 2.13, 95 % CI 1.05-4.32, p = 0.038). In post hoc analysis with extended follow-up to 18 months, the primary outcome occurred more often in the intervention group (22.5 % vs. 16.1 %, OR 1.59, 95 % CI 1.05-2.41, P = 0.029). In this effectiveness trial, individualized mailed CVD risk messages increased the frequency of new lipid-lowering drug prescriptions, but we observed no difference in proportions lowering LDL

  11. Population of nitrogen molecule electron states and structure of the fast ionization wave

    CERN Document Server

    Pancheshnyi, S V; Starikovskii, A Y

    1999-01-01

    The excitation of N sub 2 (C sup 3 supPI sub u , nu=0) and N sup + sub 2 (B sup 2 supSIGMA sup + sub u , nu=0) electron states has been studied by using a time-resolved emission spectroscopy technique. To excite the above states, the nanosecond, high-voltage, periodic impulsed discharge at low pressures in the form of the fast ionization wave (FIW) was used. The electron concentration and the average energy, electric field were found on the basis of experimental data. The spacial-temporal structure of the FIW front was investigated. It has been shown that the generation of the required electron concentration, as well as the electron level population take place behind the FIW front in residual fields. Sections corresponding to the 'electric' and 'luminous' FIW fronts are essentially separated in space. The proposed modelling electron energy distribution function describes qualitatively general regularities of the breakdown propagation in the whole range of parameters under study. (author)

  12. Topographic and spectroscopic characterization of electronic edge states in CVD grown graphene nanoribbons.

    Science.gov (United States)

    Pan, Minghu; Girão, E Costa; Jia, Xiaoting; Bhaviripudi, Sreekar; Li, Qing; Kong, Jing; Meunier, V; Dresselhaus, Mildred S

    2012-04-11

    We used scanning tunneling microscopy and spectroscopy (STM/S) techniques to analyze the relationships between the edge shapes and the electronic structures in as-grown chemical vapor deposition (CVD) graphene nanoribbons (GNRs). A rich variety of single-layered graphene nanoribbons exhibiting a width of several to 100 nm and up to 1 μm long were studied. High-resolution STM images highlight highly crystalline nanoribbon structures with well-defined and clean edges. Theoretical calculations indicate clear spin-split edge states induced by electron-electron Coulomb repulsion. The edge defects can significantly modify these edge states, and different edge structures for both sides of a single ribbon produce asymmetric electronic edge states, which reflect the more realistic features of CVD grown GNRs. Three structural models are proposed and analyzed to explain the observations. By comparing the models with an atomic resolution image at the edge, a pristine (2,1) structure was ruled out in favor of a reconstructed edge structure composed of 5-7 member rings, showing a better match with experimental results, and thereby suggesting the possibility of a defective morphology at the edge of CVD grown nanoribbons. © 2012 American Chemical Society

  13. Bimolecular Excited-State Electron Transfer with Surprisingly Long-Lived Radical Ions

    KAUST Repository

    Alsam, Amani Abdu

    2015-09-02

    We explored the excited-state interactions of bimolecular, non-covalent systems consisting of cationic poly[(9,9-di(3,3’-N,N’-trimethyl-ammonium) propyl fluorenyl-2,7-diyl)-alt-co-(9,9-dioctyl-fluorenyl-2,7-diyl)] diiodide salt (PFN) and 1,4-dicyanobenzene (DCB) using steady-state and time-resolved techniques, including femto- and nanosecond transient absorption and femtosecond infrared spectroscopies with broadband capabilities. The experimental results demonstrated that photo-induced electron transfer from PFN to DCB occurs on the picosecond time scale, leading to the formation of PFN+• and DCB-• radical ions. Interestingly, real-time observations of the vibrational marker modes on the acceptor side provided direct evidence and insight into the electron transfer process indirectly inferred from UV-Vis experiments. The band narrowing on the picosecond time scale observed on the antisymmetric C-N stretching vibration of the DCB radical anion provides clear experimental evidence that a substantial part of the excess energy is channeled into vibrational modes of the electron transfer product and that the geminate ion pairs dissociate. More importantly, our nanosecond time-resolved data indicate that the charge-separated state is very long lived ( 30 ns) due to the dissociation of the contact radical ion pair into free ions. Finally, the fast electron transfer and slow charge recombination anticipate the current donor−acceptor system with potential applications in organic solar cells.

  14. Bimolecular Excited-State Electron Transfer with Surprisingly Long-Lived Radical Ions

    KAUST Repository

    Alsam, Amani Abdu; Aly, Shawkat Mohammede; Usman, Anwar; Parida, Manas R.; Del Gobbo, Silvano; Alarousu, Erkki; Mohammed, Omar F.

    2015-01-01

    We explored the excited-state interactions of bimolecular, non-covalent systems consisting of cationic poly[(9,9-di(3,3’-N,N’-trimethyl-ammonium) propyl fluorenyl-2,7-diyl)-alt-co-(9,9-dioctyl-fluorenyl-2,7-diyl)] diiodide salt (PFN) and 1,4-dicyanobenzene (DCB) using steady-state and time-resolved techniques, including femto- and nanosecond transient absorption and femtosecond infrared spectroscopies with broadband capabilities. The experimental results demonstrated that photo-induced electron transfer from PFN to DCB occurs on the picosecond time scale, leading to the formation of PFN+• and DCB-• radical ions. Interestingly, real-time observations of the vibrational marker modes on the acceptor side provided direct evidence and insight into the electron transfer process indirectly inferred from UV-Vis experiments. The band narrowing on the picosecond time scale observed on the antisymmetric C-N stretching vibration of the DCB radical anion provides clear experimental evidence that a substantial part of the excess energy is channeled into vibrational modes of the electron transfer product and that the geminate ion pairs dissociate. More importantly, our nanosecond time-resolved data indicate that the charge-separated state is very long lived ( 30 ns) due to the dissociation of the contact radical ion pair into free ions. Finally, the fast electron transfer and slow charge recombination anticipate the current donor−acceptor system with potential applications in organic solar cells.

  15. Frequency Domain Modeling and Simulation of DC Power Electronic Systems Using Harmonic State Space Method

    DEFF Research Database (Denmark)

    Kwon, Jun Bum; Wang, Xiongfei; Blaabjerg, Frede

    2017-01-01

    For the efficiency and simplicity of electric systems, the dc power electronic systems are widely used in a variety of applications such as electric vehicles, ships, aircraft and also in homes. In these systems, there could be a number of dynamic interactions and frequency coupling between network...... with different switching frequency or harmonics from ac-dc converters makes that harmonics and frequency coupling are both problems of ac system and challenges of dc system. This paper presents a modeling and simulation method for a large dc power electronic system by using Harmonic State Space (HSS) modeling...

  16. Structure functions and final-state properties in deeply inelastic electron-proton scattering

    International Nuclear Information System (INIS)

    Kharraziha, H.

    1997-01-01

    In this thesis, we give a description of the detailed structure of the proton and a description of the final-state properties in electron-proton scattering. Qualitative results, in a purely gluonic scenario with the leading log approximation, and quantitative results, where quarks are included and some sub-leading corrections have been made, are presented. The quantitative results are in fair agreement with available experimental data and a Monte Carlo event generator for electron-proton scattering is presented. Further, a computer program for calculating QCD colour factors is presented

  17. Determination of electronic states in crystalline semiconductors and metals by angle-resolved photoemission

    International Nuclear Information System (INIS)

    Mills, K.A.

    1979-08-01

    An important part of the theoretical description of the solid state is band structure, which relies on the existence of dispersion relations connecting the electronic energy and wavevector in materials with translational symmetry. These relations determine the electronic behavior of such materials. The elaboration of accurate band structures, therefore, is of considerable fundamental and practical importance. Angle-resolved photoemission (ARP) spectroscopy provides the only presently available method for the detailed experimental investigation of band structures. This work is concerned with its application to both semiconducting and metallic single crystals

  18. Resonant Ion Pair Formation in Electron Collisions with Ground State Molecular Ions

    International Nuclear Information System (INIS)

    Zong, W.; Dunn, G.H.; Djuric, N.; Greene, C.H.; Neau, A.; Zong, W.; Larsson, M.; Al-Khalili, A.; Neau, A.; Derkatch, A.M.; Vikor, L.; Shi, W.; Rosen, S.; Le Padellec, A.; Danared, H.; Ugglas, M. af

    1999-01-01

    Resonant ion pair formation from collisions of electrons with ground state diatomic molecular ions has been observed and absolute cross sections measured. The cross section for HD + is characterized by an abrupt threshold at 1.9thinspthinspeV and 14 resolved peaks in the range of energies 0≤E≤14 eV . The dominant mechanism responsible for the structures appears to be resonant capture and stabilization, modified by two-channel quantum interference. Data on HF + show structure correlated with photoionization of HF and with dissociative recombination of electrons with this ion. copyright 1999 The American Physical Society

  19. A New Proxy Electronic Voting Scheme Achieved by Six-Particle Entangled States

    Science.gov (United States)

    Cao, Hai-Jing; Ding, Li-Yuan; Jiang, Xiu-Li; Li, Peng-Fei

    2018-03-01

    In this paper, we use quantum proxy signature to construct a new secret electronic voting scheme. In our scheme, six particles entangled states function as quantum channels. The voter Alice, the Vote Management Center Bob, the scrutineer Charlie only perform two particles measurements on the Bell bases to realize the electronic voting process. So the scheme reduces the technical difficulty and increases operation efficiency. We use quantum key distribution and one-time pad to guarantee its unconditional security. The significant advantage of our scheme is that transmitted information capacity is twice as much as the capacity of other schemes.

  20. Hydrodynamic Relaxation of an Electron Plasma to a Near-Maximum Entropy State

    International Nuclear Information System (INIS)

    Rodgers, D. J.; Servidio, S.; Matthaeus, W. H.; Mitchell, T. B.; Aziz, T.; Montgomery, D. C.

    2009-01-01

    Dynamical relaxation of a pure electron plasma in a Malmberg-Penning trap is studied, comparing experiments, numerical simulations and statistical theories of weakly dissipative two-dimensional (2D) turbulence. Simulations confirm that the dynamics are approximated well by a 2D hydrodynamic model. Statistical analysis favors a theoretical picture of relaxation to a near-maximum entropy state with constrained energy, circulation, and angular momentum. This provides evidence that 2D electron fluid relaxation in a turbulent regime is governed by principles of maximum entropy.

  1. Study of the Effects of the Electric Field on Charging Measurements on Individual Micron-size Dust Grains by Secondary Electron Emissions

    Science.gov (United States)

    Tankosic, D.; Abbas, M. M.

    2013-01-01

    The dust charging by electron impact is an important dust charging process in Astrophysical, Planetary, and the Lunar environments. Low energy electrons are reflected or stick to the grains charging the dust grains negatively. At sufficiently high energies electrons penetrate the grain leading to excitation and emission of electrons referred to as secondary electron emission (SEE). Available theoretical models for the calculation of SEE yield applicable for neutral, planar or bulk surfaces are generally based on Sternglass Equation. However, viable models for charging of individual dust grains do not exist at the present time. Therefore, the SEE yields have to be obtained by some experimental methods at the present time. We have conducted experimental studies on charging of individual micron size dust grains in simulated space environments using an electrodynamic balance (EDB) facility at NASA-MSFC. The results of our extensive laboratory study of charging of individual micron-size dust grains by low energy electron impact indicate that the SEE by electron impact is a very complex process expected to be substantially different from the bulk materials. It was found that the incident electrons may lead to positive or negative charging of dust grains depending upon the grain size, surface potential, electron energy, electron flux, grain composition, and configuration. In this paper we give a more elaborate discussion about the possible effects of the AC field in the EDB on dust charging measurements by comparing the secondary electron emission time-period (tau (sub em) (s/e)) with the time-period (tau (sub ac) (ms)) of the AC field cycle in the EDB that we have briefly addressed in our previous publication.

  2. Selective excitation of a vibrational level within the electronic ground state of a polyatomic molecule with ultra pulses

    CSIR Research Space (South Africa)

    de Clercq, L

    2010-09-01

    Full Text Available Coherent control of the upper vibrational level populations in the electronic ground state of a polyatomic molecule was simulated. Results indicate that selective excitation of a specific upper state level is possible...

  3. Free electron lasers and short wavelengths: state of the art and prospects

    International Nuclear Information System (INIS)

    Couprie, M.E.

    2003-01-01

    Free electron lasers generate coherent and adjustable radiation that is based on the interaction of a light wave with a relativistic electron beam circulating in a periodic and permanent magnetic field produced by an ondulator. The light wave comes from either - synchrotron radiation emitted by the electron packet at each round in the case of SASE (self amplified spontaneous emission) operating more, or - synchrotron radiation stored in an optic cavity in the case of oscillator operating mode, or - an external laser wave in the case of harmonic generation operating mode. Under particular conditions the light wave is amplified to the detriment of the kinetic energy of the electrons which leads to the laser effect. 5 free electron lasers are operating in the world: Super-Aco in France, Elettra in Italy, NIJI-4 and Uvsor in Japan, and Duke in Usa. The state of the art of free electron lasers in the UV, VUV range is presented and the different configurations associated to storage rings, linac and ERL (energy recovery linacs) are described. (A.C.)

  4. Electron impact excitation cross sections and rates from the ground state of atomic calcium

    CERN Document Server

    Samson, A M

    2001-01-01

    New R-matrix calculations are presented for electron excitation of atomic calcium. The target state expansion includes 22 states: 4s sup 2 sup 1 S; 4snl sup 1 sup , sup 3 L, where nl is 3d, 4p, 5s, 5p, 4d and 4f; 3d4p sup 1 sup , sup 3 P,D,F; and 4p sup 2 sup 3 P, sup 1 D, sup 1 S terms. The calculation is in LS coupling, and configuration interaction involving 3p subshell correlation is included. Electron impact excitation cross sections from the 4s sup 2 ground state to the next 10 states are tabulated for low energies, and thermally averaged effective collision strengths are tabulated over a range of electron temperatures from 1000 to 10,000 K. Comparisons are made with previous cross sections calculations for the 4s sup 2 -4s4p sup 3 P deg. transition; excellent agreement is found with experimentally derived rates for 4s sup 2 -4s4p sup 1 P deg

  5. Reaction of H2 with O2 in Excited Electronic States: Reaction Pathways and Rate Constants.

    Science.gov (United States)

    Pelevkin, Alexey V; Loukhovitski, Boris I; Sharipov, Alexander S

    2017-12-21

    Comprehensive quantum chemical analysis with the use of the multireference state-averaged complete active space self-consistent field approach was carried out to study the reactions of H 2 with O 2 in a 1 Δ g , b 1 Σ g + , c 1 Σ u - , and A' 3 Δ u electronically excited states. The energetically favorable reaction pathways and possible intersystem crossings have been revealed. The energy barriers were refined employing the extended multiconfiguration quasi-degenerate second-order perturbation theory. It has been shown that the interaction of O 2 (a 1 Δ g ) and O 2 (A' 3 Δ u ) with H 2 occurs through the H-abstraction process with relatively low activation barriers that resulted in the formation of the HO 2 molecule in A″ and A' electronic states, respectively. Meanwhile, molecular oxygen in singlet sigma states (b 1 Σ g + and c 1 Σ u - ) was proved to be nonreactive with respect to the molecular hydrogen. Appropriate rate constants for revealed reaction and quenching channels have been estimated using variational transition-state theory including corrections for the tunneling effect, possible nonadiabatic transitions, and anharmonicity of vibrations for transition states and reactants. It was demonstrated that the calculated reaction rate constant for the H 2 + O 2 (a 1 Δ g ) process is in reasonable agreement with known experimental data. The Arrhenius approximations for these processes have been proposed for the temperature range T = 300-3000 K.

  6. Coupling a Surface Acoustic Wave to an Electron Spin in Diamond via a Dark State

    Directory of Open Access Journals (Sweden)

    D. Andrew Golter

    2016-12-01

    Full Text Available The emerging field of quantum acoustics explores interactions between acoustic waves and artificial atoms and their applications in quantum information processing. In this experimental study, we demonstrate the coupling between a surface acoustic wave (SAW and an electron spin in diamond by taking advantage of the strong strain coupling of the excited states of a nitrogen vacancy center while avoiding the short lifetime of these states. The SAW-spin coupling takes place through a Λ-type three-level system where two ground spin states couple to a common excited state through a phonon-assisted as well as a direct dipole optical transition. Both coherent population trapping and optically driven spin transitions have been realized. The coherent population trapping demonstrates the coupling between a SAW and an electron spin coherence through a dark state. The optically driven spin transitions, which resemble the sideband transitions in a trapped-ion system, can enable the quantum control of both spin and mechanical degrees of freedom and potentially a trapped-ion-like solid-state system for applications in quantum computing. These results establish an experimental platform for spin-based quantum acoustics, bridging the gap between spintronics and quantum acoustics.

  7. The reliability of assigning individuals to cognitive states using the Mini Mental-State Examination: a population-based prospective cohort study.

    Science.gov (United States)

    Marioni, Riccardo E; Chatfield, Mark; Brayne, Carol; Matthews, Fiona E

    2011-09-06

    Previous investigations of test re-test reliability of the Mini-Mental State Examination (MMSE) have used correlations and statistics such as Cronbach's α to assess consistency. In practice, the MMSE is usually used to group individuals into cognitive states. The reliability of this grouping (state based approach) has not been fully explored. MMSE data were collected on a subset of 2,275 older participants (≥ 65 years) from the population-based Medical Research Council Cognitive Function and Ageing Study. Two measurements taken approximately two months apart were used to investigate three state-based categorisations. Descriptive statistics were used to determine how many people remained in the same cognitive group or went up or down groups. Weighted logistic regression was used to identify predictive characteristics of those who moved group. The proportion of people who remained in the same MMSE group at screen and follow-up assessment ranged from 58% to 78%. The proportion of individuals who went up one or more groups was roughly equal to the proportion that went down one or more groups; most of the change occurred when measurements were close to the cut-points. There was no consistently significant predictor for changing cognitive group. A state-based approach to analysing the reliability of the MMSE provided similar results to correlation analyses. State-based models of cognitive change or individual trajectory models using raw scores need multiple waves to help overcome natural variation in MMSE scores and to help identify true cognitive change.

  8. Experimental pain processing in individuals with cognitive impairment: current state of the science

    DEFF Research Database (Denmark)

    Defrin, R; Amanzio, Martina; de Tomasso, M

    2015-01-01

    Cognitive impairment (CI) can develop during the course of ageing and is a feature of many neurological and neurodegenerative diseases. Many individuals with CI have substantial, sustained and complex healthcare needs which frequently include pain. However, individuals with CI can have difficulty...... of neurological and neurodegenerative disorders in which CI is typically present. Overall, the existing data suggest that pain processing is altered in most individuals with CI compared to cognitively intact matched controls. The precise nature of these alterations varies with the type of CI (or associated...... to cognitively unimpaired individuals. Our current understanding of the neurobiological mechanisms underpinning these alterations is limited, but may be enhanced through the use of animal models of CI which also exhibit alterations in nociceptive responding. Further research employing additional behavioural...

  9. Individual differences in approach motivation, resting-state frontal cortical activity and attentional scope

    NARCIS (Netherlands)

    Boksem, M.A.S.; Kostermans, E.; Tops, M.; de Cremer, D.

    2012-01-01

    Recent research has demonstrated that individual differences in approach motivation modulate attentional scope. In turn, approach and inhibition have been related to different neural systems that are associated with asymmetries in relative frontal activity (RFA). Here, we investigated whether such

  10. Electron Microscopic Recording of the Power and Recovery Strokes of Individual Myosin Heads Coupled with ATP Hydrolysis: Facts and Implications

    Directory of Open Access Journals (Sweden)

    Haruo Sugi

    2018-05-01

    Full Text Available The most straightforward way to get information on the performance of individual myosin heads producing muscle contraction may be to record their movement, coupled with ATP hydrolysis, electron-microscopically using the gas environmental chamber (EC. The EC enables us to visualize and record ATP-induced myosin head movement in hydrated skeletal muscle myosin filaments. When actin filaments are absent, myosin heads fluctuate around a definite neutral position, so that their time-averaged mean position remains unchanged. On application of ATP, myosin heads are found to move away from, but not towards, the bare region, indicating that myosin heads perform a recovery stroke (average amplitude, 6 nm. After exhaustion of ATP, myosin heads return to their neutral position. In the actin–myosin filament mixture, myosin heads form rigor actin myosin linkages, and on application of ATP, they perform a power stroke by stretching adjacent elastic structures because of a limited amount of applied ATP ≤ 10 µM. The average amplitude of the power stroke is 3.3 nm and 2.5 nm at the distal and the proximal regions of the myosin head catalytic domain (CAD, respectively. The power stroke amplitude increases appreciably at low ionic strength, which is known to enhance Ca2+-activated force in muscle. In both the power and recovery strokes, myosin heads return to their neutral position after exhaustion of ATP.

  11. Modeling duration choice in space–time multi-state supernetworks for individual activity-travel scheduling

    NARCIS (Netherlands)

    Liao, F.

    2016-01-01

    Multi-state supernetworks have been advanced recently for modeling individual activity-travel scheduling decisions. The main advantage is that multi-dimensional choice facets are modeled simultaneously within an integral framework, supporting systematic assessments of a large spectrum of policies

  12. Induced Rashba splitting of electronic states in monolayers of Au, Cu on a W(110) substrate

    International Nuclear Information System (INIS)

    Shikin, A M; Rybkina, A A; Rybkin, A G; Marchenko, D; Korshunov, A S; Kudasov, Yu B; Frolova, N V; Sánchez-Barriga, J; Varykhalov, A; Rader, O

    2013-01-01

    The paper sums up a theoretical and experimental investigation of the influence of the spin–orbit coupling in W(110) on the spin structure of electronic states in deposited Au and Cu monolayers. Angle-resolved photoemission spectroscopy reveals that in the case of monolayers of Au and Cu spin–orbit split bands are formed in a surface-projected gap of W(110). Spin resolution shows that these states are spin polarized and that, therefore, the spin–orbit splitting is of Rashba type. The states evolve from hybridization of W 5d, 6p-derived states with the s, p states of the deposited metal. Interaction with Au and Cu shifts the original W 5d-derived states from the edges toward the center of the surface-projected gap. The size of the spin–orbit splitting of the formed states does not correlate with the atomic number of the deposited metal and is even higher for Cu than for Au. These states can be described as W-derived surface resonances modified by hybridization with the p, d states of the adsorbed metal. Our electronic structure calculations performed in the framework of the density functional theory correlate well with the experiment and demonstrate the crucial role of the W top layer for the spin–orbit splitting. It is shown that the contributions of the spin–orbit interaction from W and Au act in opposite directions which leads to a decrease of the resulting spin–orbit splitting in the Au monolayer on W(110). For the Cu monolayer with lower spin–orbit interaction the resulting spin splitting is higher and mainly determined by the W. (paper)

  13. Quasi 2D electronic states with high spin-polarization in centrosymmetric MoS2 bulk crystals

    Science.gov (United States)

    Gehlmann, Mathias; Aguilera, Irene; Bihlmayer, Gustav; Młyńczak, Ewa; Eschbach, Markus; Döring, Sven; Gospodarič, Pika; Cramm, Stefan; Kardynał, Beata; Plucinski, Lukasz; Blügel, Stefan; Schneider, Claus M.

    2016-06-01

    Time reversal dictates that nonmagnetic, centrosymmetric crystals cannot be spin-polarized as a whole. However, it has been recently shown that the electronic structure in these crystals can in fact show regions of high spin-polarization, as long as it is probed locally in real and in reciprocal space. In this article we present the first observation of this type of compensated polarization in MoS2 bulk crystals. Using spin- and angle-resolved photoemission spectroscopy (ARPES), we directly observed a spin-polarization of more than 65% for distinct valleys in the electronic band structure. By additionally evaluating the probing depth of our method, we find that these valence band states at the point in the Brillouin zone are close to fully polarized for the individual atomic trilayers of MoS2, which is confirmed by our density functional theory calculations. Furthermore, we show that this spin-layer locking leads to the observation of highly spin-polarized bands in ARPES since these states are almost completely confined within two dimensions. Our findings prove that these highly desired properties of MoS2 can be accessed without thinning it down to the monolayer limit.

  14. Electronic structure and charge transfer excited states of endohedral fullerene containing electron donoracceptor complexes utilized in organic photovoltaics

    Science.gov (United States)

    Amerikheirabadi, Fatemeh

    Organic Donor-Acceptor complexes form the main component of the organic photovoltaic devices (OPVs). The open circuit voltage of OPVs is directly related to the charge transfer excited state energies of these complexes. Currently a large number of different molecular complexes are being tested for their efficiency in photovoltaic devices. In this work, density functional theory as implemented in the NRLMOL code is used to investigate the electronic structure and related properties of these donor-acceptor complexes. The charge transfer excitation energies are calculated using the perturbative delta self-consistent field method recently developed in our group as the standard time dependent density functional approaches fail to accurately provide them. The model photovoltaics systems analyzed are as follows: Sc3N C 80--ZnTPP, Y3 N C80-- ZnTPP and Sc3 N C80-- ZnPc. In addition, a thorough analysis of the isolated donor and acceptor molecules is also provided. The studied acceptors are chosen from a class of fullerenes named trimetallic nitride endohedral fullerenes. These molecules have shown to possess advantages as acceptors such as long lifetimes of the charge-separated states.

  15. Ab initio/interpolated quantum dynamics on coupled electronic states with full configuration interaction wave functions

    International Nuclear Information System (INIS)

    Thompson, K.; Martinez, T.J.

    1999-01-01

    We present a new approach to first-principles molecular dynamics that combines a general and flexible interpolation method with ab initio evaluation of the potential energy surface. This hybrid approach extends significantly the domain of applicability of ab initio molecular dynamics. Use of interpolation significantly reduces the computational effort associated with the dynamics over most of the time scale of interest, while regions where potential energy surfaces are difficult to interpolate, for example near conical intersections, are treated by direct solution of the electronic Schroedinger equation during the dynamics. We demonstrate the concept through application to the nonadiabatic dynamics of collisional electronic quenching of Li(2p). Full configuration interaction is used to describe the wave functions of the ground and excited electronic states. The hybrid approach agrees well with full ab initio multiple spawning dynamics, while being more than an order of magnitude faster. copyright 1999 American Institute of Physics

  16. Space-group approach to two-electron states in unconventional superconductors

    International Nuclear Information System (INIS)

    Yarzhemsky, V. G.

    2008-01-01

    The direct application of the space-group representation theory, makes possible to obtain limitations for the symmetry of SOP on lines and planes of symmetry in one-electron Brillouin zone. In the case of highly symmetric UPt 3 only theoretical nodal structure of IR E 2u is in agreement with all the experimental results. On the other hand, in the case of high-T c superconductors the two electron description of Cooper pairs in D 2h symmetry is not sufficient to describe experimental nodal structure. It was shown that in this case, the nodal structure is the result of underlying interactions between two-electron states and hidden symmetry D-4 h . (author)

  17. Photo- and radiation chemical studies of intermediates involved in excited-state electron-transfer reactions

    International Nuclear Information System (INIS)

    Hoffman, M.Z.

    1985-01-01

    Excited-state inter- and intramolecular electron-transfer reactions lie at the heart of the most photochemical solar energy conversion schemes. The authors research, which has utilized the techniques of continuous and pulsed photolysis and radiolysis, has focused on three general aspects of these reactions involving transition metal coordination complexes and electron donor-acceptor complexes: i) the effect of solution medium on the properties and quenching of the excited states; ii) the control of the quantum yields of formation of redox products; iii) the mechanism by which reduced species interact with water to yield H 2 homogeneously and heterogeneously. EDTA is among the most popular sacrificial electron donors used in model systems. Its role is to scavenge the oxidized form of the photosensitizer in order to prevent its rapid reaction with the reduced form of the electron relay species that results from the electron-transfer quenching of the excited photosensitizer. In systems involving MV 2+ , the radicals resulting from the oxidation of EDTA can eventually lead to the generation of a second equivalent of MV + ; the reducing agent is believed to be a radical localized on the carbon atom alpha to the carboxylate group. The reaction of radiolytically-generated OH/H with EDTA produces this radical directly via H-abstraction or indirectly via deprotonation of the carbon atom adjacent to the nitrogen radical site in the oxidized amine moiety; it reduces MV 2+ with rate constants of 2.8 x 10 9 , 7.6 x 10 9 , and 8.5 x 10 6 M -1 s -1 at pH 12.5, 8.3, and 4.7, respectively. Degradative decarboxylation of EDTA-radicals and their back electron-transfer reactions are enhanced in acidic solution causing the yield of MV + to be severely diminished

  18. Hybridized electronic states in potassium-doped picene probed by soft x-ray spectroscopies

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yamane

    2012-12-01

    Full Text Available The electronic structure of the unoccupied and occupied states of potassium (K-doped and undoped picene crystalline films has been investigated by using the element-selective and bulk-sensitive photon-detection methods of X-ray absorption and emission spectroscopies. We observed the formation of the doping-induced unoccupied and occupied electronic states in K-doped picene. By applying the inner-shell resonant-excitation experiments, we observed the evidence for the orbital hybridization between K and picene near the Fermi energy. Furthermore, the resonant X-ray emission experiment suggests the presence of the Raman-active vibronic interaction in K-doped picene. These experimental evidences play a crucial role in the superconductivity of K-doped picene.

  19. Inner Sound: Altered States of Consciousness in Electronic Music and Audio-Visual Media

    DEFF Research Database (Denmark)

    Weinel, Jonathan

    Over the last century, developments in electronic music and art have enabled new possibilities for creating audio and audio-visual artworks. With this new potential has come the possibility for representing subjective internal conscious states, such as the experience of hallucinations, using...... the creative influence of ASCs, from Amazonian chicha festivals to the synaesthetic assaults of neon raves; and from an immersive outdoor electroacoustic performance on an Athenian hilltop to a mushroom trip on a tropical island in virtual reality. Beginning with a discussion of consciousness, the book...... explores how our subjective realities may change during states of dream, psychedelic experience, meditation, and trance. Taking a broad view across a wide range of genres, Inner Sound draws connections between shamanic art and music, and the modern technoshamanism of psychedelic rock, electronic dance...

  20. Electronic states of zigzag graphene nanoribbons with edges reconstructed with topological defects

    Energy Technology Data Exchange (ETDEWEB)

    Pincak, R., E-mail: pincak@saske.sk [Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 043 53 Kosice (Slovakia); Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation); Smotlacha, J., E-mail: smota@centrum.cz [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation); Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Brehova 7, 110 00 Prague (Czech Republic); Osipov, V.A., E-mail: osipov@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation)

    2015-10-15

    The energy spectrum and electronic density of states (DOS) of zigzag graphene nanoribbons with edges reconstructed with topological defects are investigated within the tight-binding method. In case of the Stone–Wales zz(57) edge the low-energy spectrum is markedly changed in comparison to the pristine zz edge. We found that the electronic DOS at the Fermi level is different from zero at any width of graphene nanoribbons. In contrast, for ribbons with heptagons only at one side and pentagons at another one the energy gap at the Fermi level is open and the DOS is equal to zero. The reason is the influence of uncompensated topological charges on the localized edge states, which are topological in nature. This behavior is similar to that found for the structured external electric potentials along the edges.

  1. Proceedings of the workshop on 'anomalous electronic states and physical properties in high-temperature superconductors'

    International Nuclear Information System (INIS)

    Arai, Masatoshi; Kajimoto, Ryoichi

    2007-03-01

    A workshop entitled 'Anomalous Electronic States and Physical Properties in High-Temperature Superconductors' was held on November 7-8, 2006 at Institute for Materials Research, Tohoku University. In the workshop, leading scientists in the field of high-T c superconductivity, both experimentalists and theorists, gathered in a hall to report the recent progress of the study, clarify the problems to be solved, and discuss the future prospects. The workshop was jointly organized by Specially Promoted Research of MEXT, Development of the 4D Spaces Access Neutron Spectrometer and Elucidation of the Mechanism of Oxide High-T c Superconductivity' (repr. by M. Arai, JAEA) and by the Inter-university Cooperative Research Program of the Institute for Materials Research, Tohoku University, 'Anomalous Electronic States and Physical Properties in High-Temperature Superconductors' (repr. by T. Tohyama, Kyoto Univ.). This report includes abstracts and materials of the presentations in the workshop. (author)

  2. Cognitive benefit and cost of acute stress is differentially modulated by individual brain state.

    Science.gov (United States)

    Kohn, Nils; Hermans, Erno J; Fernández, Guillén

    2017-07-01

    Acute stress is associated with beneficial as well as detrimental effects on cognition in different individuals. However, it is not yet known how stress can have such opposing effects. Stroop-like tasks typically show this dissociation: stress diminishes speed, but improves accuracy. We investigated accuracy and speed during a stroop-like task of 120 healthy male subjects after an experimental stress induction or control condition in a randomized, counter-balanced cross-over design; we assessed brain-behavior associations and determined the influence of individual brain connectivity patterns on these associations, which may moderate the effect and help identify stress resilience factors. In the mean, stress was associated to increase in accuracy, but decrease in speed. Accuracy was associated to brain activation in a distributed set of brain regions overlapping with the executive control network (ECN) and speed to temporo-parietal activation. In line with a stress-related large-scale network reconfiguration, individuals showing an upregulation of the salience and down-regulation of the executive-control network under stress displayed increased speed, but decreased performance. In contrast, individuals who upregulate their ECN under stress show improved performance. Our results indicate that the individual large-scale brain network balance under acute stress moderates cognitive consequences of threat. © The Author (2017). Published by Oxford University Press.

  3. Cognitive benefit and cost of acute stress is differentially modulated by individual brain state

    Science.gov (United States)

    Hermans, Erno J.; Fernández, Guillén

    2017-01-01

    Abstract Acute stress is associated with beneficial as well as detrimental effects on cognition in different individuals. However, it is not yet known how stress can have such opposing effects. Stroop-like tasks typically show this dissociation: stress diminishes speed, but improves accuracy. We investigated accuracy and speed during a stroop-like task of 120 healthy male subjects after an experimental stress induction or control condition in a randomized, counter-balanced cross-over design; we assessed brain–behavior associations and determined the influence of individual brain connectivity patterns on these associations, which may moderate the effect and help identify stress resilience factors. In the mean, stress was associated to increase in accuracy, but decrease in speed. Accuracy was associated to brain activation in a distributed set of brain regions overlapping with the executive control network (ECN) and speed to temporo-parietal activation. In line with a stress-related large-scale network reconfiguration, individuals showing an upregulation of the salience and down-regulation of the executive-control network under stress displayed increased speed, but decreased performance. In contrast, individuals who upregulate their ECN under stress show improved performance. Our results indicate that the individual large-scale brain network balance under acute stress moderates cognitive consequences of threat. PMID:28402480

  4. Sensitive plant (Mimosa pudica hiding time depends on individual and state

    Directory of Open Access Journals (Sweden)

    Sarah Reed-Guy

    2017-07-01

    Full Text Available The decisions animals make to adjust their antipredator behavior to rapidly changing conditions have been well studied. Inducible defenses in plants are an antipredator behavior that acts on a longer time scale, but sensitive plants, Mimosa pudica, have a much more rapid antipredator response; they temporarily close their leaves when touched. The time they remain closed is defined as hiding time. We studied hiding time in sensitive plants and found that individual plants differed significantly in their hiding times. We then showed that the effect of individual explained substantial variation in hiding time on a short time scale. Finally, on a longer time scale, individuality persisted but the amount of variation attributed to individual decreased. We hypothesized that variation in plant condition might explain this change. We therefore manipulated sunlight availability and quantified hiding time. When deprived of light for 6 h, sensitive plants significantly shortened their hiding times. But when only half a plant was deprived of light, hiding times on the deprived half and light exposed half were not significantly different. This suggests that overall condition best explains variation in sensitive plant antipredator behavior. Just like in animals, sensitive plant antipredator behavior is condition dependent, and, just like in animals, a substantial amount of the remaining variation is explained by individual differences between plants. Thus, models designed to predict plasticity in animal behavior may be successfully applied to understand behavior in other organisms, including plants.

  5. Two-dimensional electron states bound to an off-plane donor in a magnetic field

    International Nuclear Information System (INIS)

    Bruno-Alfonso, A; Candido, L; Hai, G-Q

    2010-01-01

    The states of an electron confined in a two-dimensional (2D) plane and bound to an off-plane donor impurity center, in the presence of a magnetic field, are investigated. The energy levels of the ground state and the first three excited states are calculated variationally. The binding energy and the mean orbital radius of these states are obtained as a function of the donor center position and the magnetic field strength. The limiting cases are discussed for an in-plane donor impurity (i.e. a 2D hydrogen atom) as well as for the donor center far away from the 2D plane in strong magnetic fields, which corresponds to a 2D harmonic oscillator.

  6. Excited-state dynamics of oxazole: A combined electronic structure calculations and dynamic simulations study

    International Nuclear Information System (INIS)

    Cao, Jun; Xie, Zhi-Zhong; Yu, Xiaodong

    2016-01-01

    In the present work, the combined electronic structure calculations and surface hopping simulations have been performed to investigate the excited-state decay of the parent oxazole in the gas phase. Our calculations show that the S_2 state decay of oxazole is an ultrafast process characterized by the ring-opening and ring-closure of the five-membered oxazole ring, in which the triplet contribution is minor. The ring-opening involves the O−C bond cleavage affording the nitrile ylide and airine intermediates, while the ring-closure gives rise to a bicyclic species through a 2−5 bond formation. The azirine and bicyclic intermediates in the S_0 state are very likely involved in the phototranspositions of oxazoles. This is different from the previous mechanism in which these intermediates in the T_1 state have been proposed for these phototranspositions.

  7. In-medium scaling law and electron scattering from high-spin states in 208Pb

    International Nuclear Information System (INIS)

    Arias de Saavedra, F.; Lallena, A.M.

    1994-01-01

    The effects of the environment modifications in the structure of the low-lying high-spin states of 208 Pb are studied by analyzing how the in-medium scaling law works on the excitation energies, wave functions, and electron scattering form factors corresponding to these states. It is shown that the consideration of f π * in addition to the effective ρ-meson mass does not affect too much most of the states analyzed. However, some of them appear to be extremely sensitive to its inclusion in the residual nucleon-nucleon interaction. As a result, a value of m ρ * /m ρ ∼f π * /f π ∼0.91 gives a good description of the (e,e') form factors of these particular states without any quenching factor. This value is in agreement with the one found for 48 Ca in a similar analysis performed in a previous work

  8. Excited-state dynamics of oxazole: A combined electronic structure calculations and dynamic simulations study

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Jun [Guizhou Provincial Key Laboratory of Computational Nano-material Science, Guizhou Education University, Guiyang, Guizhou 550018 (China); Guizhou Synergetic Innovation Center of Scientific Big Data for Advanced Manufacturing Technology, Guizhou Education University, Guiyang 550018 (China); Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Xie, Zhi-Zhong [Department of Chemistry, School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070 (China); Yu, Xiaodong, E-mail: yuxdhy@163.com [Department of Architecture and Chemical Engineering, Tangshan Polytechnic College, Tangshan 063020 (China)

    2016-08-02

    In the present work, the combined electronic structure calculations and surface hopping simulations have been performed to investigate the excited-state decay of the parent oxazole in the gas phase. Our calculations show that the S{sub 2} state decay of oxazole is an ultrafast process characterized by the ring-opening and ring-closure of the five-membered oxazole ring, in which the triplet contribution is minor. The ring-opening involves the O−C bond cleavage affording the nitrile ylide and airine intermediates, while the ring-closure gives rise to a bicyclic species through a 2−5 bond formation. The azirine and bicyclic intermediates in the S{sub 0} state are very likely involved in the phototranspositions of oxazoles. This is different from the previous mechanism in which these intermediates in the T{sub 1} state have been proposed for these phototranspositions.

  9. The use of quadratic forms in the calculation of ground state electronic structures

    International Nuclear Information System (INIS)

    Keller, Jaime; Weinberger, Peter

    2006-01-01

    There are many examples in theoretical physics where a fundamental quantity can be considered a quadratic form ρ=Σ i ρ i =vertical bar Ψ vertical bar 2 and the corresponding linear form Ψ=Σ i ψ i is highly relevant for the physical problem under study. This, in particular, is the case of the density and the wave function in quantum mechanics. In the study of N-identical-fermion systems we have the additional feature that Ψ is a function of the 3N configuration space coordinates and ρ is defined in three-dimensional real space. For many-electron systems in the ground state the wave function and the Hamiltonian are to be expressed in terms of the configuration space (CS), a replica of real space for each electron. Here we present a geometric formulation of the CS, of the wave function, of the density, and of the Hamiltonian to compute the electronic structure of the system. Then, using the new geometric notation and the indistinguishability and equivalence of the electrons, we obtain an alternative computational method for the ground state of the system. We present the method and discuss its usefulness and relation to other approaches

  10. On the bonding nature of electron states for the Fe-Mo double perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Carvajal, E.; Cruz-Irisson, M. [ESIME-Culhuacán, Instituto Politécnico Nacional, Av. Santa Ana 1000, C.P. 04430, México, D.F. (Mexico); Oviedo-Roa, R. [Programa de Investigación en Ingeniería Molecular, Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, C.P. 07730, México, D.F. (Mexico); Navarro, O. [Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, A.P. 70-360, 04510, México, D.F. (Mexico)

    2014-05-15

    The electronic transport as well as the effect of an external magnetic field has been investigated on manganese-based materials, spinels and perovskites. Potential applications of double perovskites go from magnetic sensors to electrodes in solid-oxide fuel cells; besides the practical interests, it is known that small changes in composition modify radically the physical properties of double perovskites. We have studied the Sr{sub 2}FeMoO{sub 6} double perovskite compound (SFMO) using first-principles density functional theory. The calculations were done within the generalized gradient approximation (GGA) scheme with the Perdew-Burke-Ernzerhof (PBE) functional. We have made a detailed analysis of each electronic state and the charge density maps around the Fermi level. For the electronic properties of SFMO it was used a primitive cell, for which we found the characteristic half-metallic behavior density of states composed by e{sub g} and t{sub 2g} electrons from Fe and Mo atoms. Those peaks were tagged as bonding or antibonding around the Fermi level at both, valence and conduction bands.

  11. Is the Spencer-Attix cavity equation applicable for solid-state detectors irradiated in megavoltage electron beams?

    International Nuclear Information System (INIS)

    Mobit, P.N.; Sandison, G.A.; Calgary Univ., AB

    2001-01-01

    The applicability of the Spencer-Attix cavity equation in determining absorbed doses in water using solid state detectors irradiated by megavoltage electron beams have been examined. The calculations were performed using the EGSnrc Monte Carlo code. This work is an extension of a recently published article examining the perturbation of dose by solid state detectors in megavoltage electron beams. (orig.)

  12. 76 FR 82279 - Electronic Delivery of Search Results From the United States Patent and Trademark Office to the...

    Science.gov (United States)

    2011-12-30

    ...] Electronic Delivery of Search Results From the United States Patent and Trademark Office to the European... United States Patent and Trademark Office (USPTO) has recently begun electronic delivery of search... the search results from a previously filed patent application to which the European patent application...

  13. Doubly excited 3Pe resonance states of two-electron positive ions in Debye plasmas

    International Nuclear Information System (INIS)

    Hu, Xiao-Qing; Wang, Yang; Kar, Sabyasachi; Jiang, Zishi; Jiang, Pinghui

    2015-01-01

    We investigate the doubly excited 3 P e resonance states of two-electron positive ions Li + , Be 2+ , B 3+ , and C 4+ by employing correlated exponential wave functions. In the framework of the stabilization method, we calculate two series (3pnp and 3dnd) of 3 P e resonances below the N = 3 threshold. The 3 P e resonance parameters (resonance energies and widths) are reported for the first time as a function of the screening parameter. For free-atomic cases, comparisons are made with the reported results and few resonance states are reported for the first time

  14. Obstacles and opportunities in the commercialization of the solid-state-electronic fluorescent-lighting ballast

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R.; Marcus, A.A.; Campbell, R.S.; Sommers, P.; Skumatz, L.; Berk, B.; Petty, P.; Eschbach, C.

    1981-10-01

    The Solid State Ballast (SSB) Program, aimed at improving the efficiency of fluorescent lights, is described. The first generation of solid state electronic ballasts has been developed and the technology has been transferred to the private sector. This report examines the opportunities for rapid dissemination of this technology into the marketplace. It includes a description of product characteristics and their influence on the commercialization of the SSB, a description of the technology delivery system presently used by the ballast industry, an analysis of the market for SSB, and identification of some high-leverage opportunities to accelerate the commercialization process. (MCW)

  15. The Generalized Coherent State ansatz: Application to quantum electron-vibrational dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Borrelli, Raffaele, E-mail: raffaele.borrelli@unito.it [DISAFA, Università di Torino, I-10095 Grugliasco (Italy); Gelin, Maxim F. [Departement of Chemistry, Technische Universität München, D-85747 Garching (Germany)

    2016-12-20

    A new ansatz for molecular vibronic wave functions based on a superposition of time-dependent Generalized Coherent States is developed and analysed. The methodology is specifically tailored to describe the time evolution of the wave function of a system in which several interacting electronic states are coupled to a bath of harmonic oscillators. The equations of motion for the wave packet parameters are obtained by using the Dirac–Frenkel time-dependent variational principle. The methodology is used to describe the quantum dynamical behavior of a model polaron system and its scaling and convergence properties are discussed and compared with numerically exact results.

  16. Numerology, hydrogenic levels, and the ordering of excited states in one-electron atoms

    Science.gov (United States)

    Armstrong, Lloyd, Jr.

    1982-03-01

    We show that the observed ordering of Rydberg states of one-electron atoms can be understood by assuming that these states are basically hydrogenic in nature. Much of the confusion concerning this point is shown to arise from the failure to differentiate between hydrogenic ordering as the nuclear charge approaches infinity, and hydrogenic ordering for an effective charge of one. The origin of κ ordering of Rydberg levels suggested by Sternheimer is considered within this picture, and the predictions of κ ordering are compared with those obtained by assuming hydrogenic ordering.

  17. Are cultures becoming individualistic? A cross-temporal comparison of individualism-collectivism in the United States and Japan.

    Science.gov (United States)

    Hamamura, Takeshi

    2012-02-01

    Individualism-collectivism is one of the best researched dimensions of culture in psychology. One frequently asked but underexamined question regards its cross-temporal changes: Are cultures becoming individualistic? One influential theory of cultural change, modernization theory, predicts the rise of individualism as a consequence of economic growth. Findings from past research are generally consistent with this theory, but there is also a body of evidence suggesting its limitations. To examine these issues, cross-temporal analyses of individualism-collectivism in the United States and Japan were conducted. Diverging patterns of cultural changes were found across indices: In both countries, some of the obtained indices showed rising individualism over the past several decades, supporting the modernization theory. However, other indices showed patterns that are best understood within the frameworks of a shifting focus of social relationships and a persisting cultural heritage. A comprehensive theory of cultural change requires considerations of these factors in addition to the modernization effect.

  18. Quantum State Transfer from a Single Photon to a Distant Quantum-Dot Electron Spin

    Science.gov (United States)

    He, Yu; He, Yu-Ming; Wei, Yu-Jia; Jiang, Xiao; Chen, Kai; Lu, Chao-Yang; Pan, Jian-Wei; Schneider, Christian; Kamp, Martin; Höfling, Sven

    2017-08-01

    Quantum state transfer from flying photons to stationary matter qubits is an important element in the realization of quantum networks. Self-assembled semiconductor quantum dots provide a promising solid-state platform hosting both single photon and spin, with an inherent light-matter interface. Here, we develop a method to coherently and actively control the single-photon frequency bins in superposition using electro-optic modulators, and measure the spin-photon entanglement with a fidelity of 0.796 ±0.020 . Further, by Greenberger-Horne-Zeilinger-type state projection on the frequency, path, and polarization degrees of freedom of a single photon, we demonstrate quantum state transfer from a single photon to a single electron spin confined in an InGaAs quantum dot, separated by 5 m. The quantum state mapping from the photon's polarization to the electron's spin is demonstrated along three different axes on the Bloch sphere, with an average fidelity of 78.5%.

  19. Spin-state blockade in Te6+-substituted electron-doped LaCoO3

    Science.gov (United States)

    Tomiyasu, Keisuke; Koyama, Shun-Ichi; Watahiki, Masanori; Sato, Mika; Nishihara, Kazuki; Onodera, Mitsugi; Iwasa, Kazuaki; Nojima, Tsutomu; Yamasaki, Yuuichi; Nakao, Hironori; Murakami, Youichi

    2015-03-01

    Perovskite-type LaCoO3 (Co3+: d6) is a rare inorganic material with sensitive and characteristic responses among low, intermediate, and high spin states. For example, in insulating nonmagnetic low-spin states below about 20 K, light hole doping (Ni substitution) induces much larger magnetization than expected; over net 10μB/hole (5μB/Ni) for 1μB/hole (1μB/Ni), in which the nearly isolated dopants locally change the surrounding Co low-spin states to magnetic ones and form spin molecules with larger total spin. Further, the former is isotropic, whereas the latter exhibits characteristic anisotropy probably because of Jahn-Teller distortion. In contrast, for electron doping, relatively insensitive spin-state responses were reported, as in LaCo(Ti4+) O3, but are not clarified, and are somewhat controversial. Here, we present macroscopic measurement data of another electron-doped system LaCo(Te6+) O3 and discuss the spin-state responses. This study was financially supported by Grants-in-Aid for Young Scientists (B) (No. 22740209 and 26800174) from the MEXT of Japan.

  20. GOVERNMENT ELECTRONIC PURCHASING: AN ASSESSMENT OF BRAZILIAN STATE GOVERNMENTS' E-PROCUREMENT WEBSITES

    OpenAIRE

    Alves, Tomaz Rodrigo; Universidade de São Paulo; Souza, Cesar Alexandre; Universidade de São Paulo

    2011-01-01

    One of the electronic government applications that has been fast developing in Brazil is e-procurement. It’s a field that allows relatively objective measuring, regarding price cuts and savings generated by the reduction of bureaucracy. This research evaluated the quality of the e-procurement portals of the 26 Brazilian state governments and also the Federal District, considering primarily features that could be useful to suppliers. In order to do so, a scoring method was developed, in which ...

  1. Changes of surface electron states of InP under soft X-rays irradiation

    International Nuclear Information System (INIS)

    Yang Zhian; Yang Zushen; Jin Tao; Qui Rexi; Cui Mingqi; Liu Fengqin

    1999-01-01

    Changes of surface electronic states of InP under 1 keV X-ray irradiation is studied by X-ray photoelectron spectroscopy (XPS) and ultraviolet ray energy spectroscopy (UPS). The results show that the soft X-ray irradiation has little effect on In atoms but much on P atoms. The authors analysed the mechanism of irradiation and explained the major effect

  2. Potential energy curve of Be2 in its ground electronic state

    Czech Academy of Sciences Publication Activity Database

    Špirko, Vladimír

    2006-01-01

    Roč. 235, č. 2 (2006), s. 268-270 ISSN 0022-2852 R&D Projects: GA AV ČR(CZ) IAA400550511 Institutional research plan: CEZ:AV0Z40550506 Keywords : ground electronic state of Be2 * MR-CI ab initio potentials * reduced potential curves Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.260, year: 2006

  3. Electron density of states in a one-dimensional distorted system with impurities: Coherent potential approximation

    International Nuclear Information System (INIS)

    Bulka, B.R.

    1982-04-01

    A tight-binding one-dimensional distorted system with impurities is considered and the electron density of states is calculated in the coherent potential approximation. It is shown that two types of impurities, an impurity built in a chain and a domain wall (a soliton), play the essential role and a drastic reduction of the energy gap is observed for a few per cent of impurities. The experimental situation in polyacetylene is also discussed. (author)

  4. Individual behaviour of Baltic cod (Gadus morhua) in relation to sex and reproductive state

    DEFF Research Database (Denmark)

    Nielsen, Birgitte; Hüssy, Karin; Neuenfeldt, Stefan

    2013-01-01

    between sexes in the timing of the onset of migration and the duration of migration from feeding grounds to the spawning area. While there was no significant difference in duration of the spawning period between females and males, the histological indices suggest that females finish spawning before males...... of the spawning period differs between sexes, as does the level of activity during spawning events. Not all individuals followed the general pattern; a considerable number of individuals were found to spawn in shallow water in the Arkona Basin, and juvenile fish undertook the migration without spawning...

  5. Electronic states of aryl radical functionalized graphenes: Density functional theory study

    Science.gov (United States)

    Tachikawa, Hiroto; Kawabata, Hiroshi

    2016-06-01

    Functionalized graphenes are known as a high-performance molecular device. In the present study, the structures and electronic states of the aryl radical functionalized graphene have been investigated by the density functional theory (DFT) method to elucidate the effects of functionalization on the electronic states of graphene (GR). Also, the mechanism of aryl radical reaction with GR was investigated. The benzene, biphenyl, p-terphenyl, and p-quaterphenyl radicals [denoted by (Bz) n (n = 1-4), where n means numbers of benzene rings in aryl radical] were examined as aryl radicals. The DFT calculation of GR-(Bz) n (n = 1-4) showed that the aryl radical binds to the carbon atom of GR, and a C-C single bond was formed. The binding energies of aryl radicals to GR were calculated to be ca. 6.0 kcal mol-1 at the CAM-B3LYP/6-311G(d,p) level. It was found that the activation barrier exists in the aryl radical addition: the barrier heights were calculated to be 10.0 kcal mol-1. The electronic states of GR-(Bz) n were examined on the basis of theoretical results.

  6. Progress in increasing electronic reporting of laboratory results to public health agencies--United States, 2013.

    Science.gov (United States)

    2013-09-27

    Electronic reporting of laboratory results to public health agencies can improve public health surveillance for reportable diseases and conditions by making reporting more timely and complete. Since 2010, CDC has provided funding to 57 state, local, and territorial health departments through the Epidemiology and Laboratory Capacity for Infectious Diseases cooperative agreement to assist with improving electronic laboratory reporting (ELR) from clinical and public health laboratories to public health agencies. As part of this agreement, CDC and state and large local health departments are collaborating to monitor ELR implementation in the United States by developing data from each jurisdiction regarding total reporting laboratories, laboratories sending ELR by disease category and message format, and the number of ELR laboratory reports compared with the total number of laboratory reports. At the end of July 2013, 54 of the 57 jurisdictions were receiving at least some laboratory reports through ELR, and approximately 62% of 20 million laboratory reports were being received electronically, compared with 54% in 2012. Continued progress will require collaboration between clinical laboratories, laboratory information management system (LIMS) vendors, and public health agencies.

  7. Hydrogen treatment as a detergent of electronic trap states in lead chalcogenide nanoparticles

    Science.gov (United States)

    Voros, Marton; Brawand, Nicholas; Galli, Giulia

    Lead chalcogenide (PbX) nanoparticles are promising materials for solar energy conversion. However, the presence of trap states in their electronic gap limits their usability, and developing a universal strategy to remove trap states is a persistent challenge. Using calculations based on density functional theory, we show that hydrogen acts as an amphoteric impurity on PbX nanoparticle surfaces; hydrogen atoms may passivate defects arising from ligand imbalance or off-stoichiometric surface terminations, irrespective of whether they originate from cation or anion excess. In addition, we show, using constrained density functional theory calculations, that hydrogen treatment of defective nanoparticles is also beneficial for charge transport in films. We also find that hydrogen adsorption on stoichiometric nanoparticles leads to electronic doping, preferentially n-type. Our findings suggest that post-synthesis hydrogen treatment of lead chalcogenide nanoparticle films is a viable approach to reduce electronic trap states or to dope well-passivated films. Work supported by the Center for Advanced Solar Photophysics, an Energy Frontier Research Center funded by the US Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences (NB) and U.S. DOE under Contract No. DE-AC02-06CH11357 (MV).

  8. Electronically excited states of chloroethylenes: Experiment and DFT calculations in comparison

    International Nuclear Information System (INIS)

    Khvostenko, O.G.

    2014-01-01

    Highlights: • B3LYP/6-311 + G(d,p) calculations of chloroethylenes molecules were performed. • Calculations were correlated with experiment on the molecules ground and excited states. • The general pattern of electron structure of chloroethylenes was obtained. • Necessity of this data for chloroethylenes negative ions study was noted. - Abstract: B3LYP/6-311 + G(d,p) calculations of ground and electronically excited states of ethylene, chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene-cis, 1,2-dichloroethylene-trans trichloroethylene and tetrachloroethylene molecules have been performed. Molecular orbitals images and orbital correlation diagram are given. The calculation results for chloroethylenes electronically excited states were compared with experimental data from the energy-loss spectra obtained and generally considered previously by C.F. Koerting, K.N. Walzl and A. Kupperman. Several new additional triplet and singlet transitions were pointed out in these spectra considering the calculation results. The finding of the additional transitions was supported by the UV absorption spectrum of trichloroethylene recorded in big cuvette (10 cm), where the first three triplet and two low-intensive forbidden singlet transitions were registered. The first triplet of this compound was recorded to be at the same energy as was found with the energy-loss spectroscopy

  9. Electronically excited states of chloroethylenes: Experiment and DFT calculations in comparison

    Energy Technology Data Exchange (ETDEWEB)

    Khvostenko, O.G., E-mail: khv@mail.ru

    2014-08-15

    Highlights: • B3LYP/6-311 + G(d,p) calculations of chloroethylenes molecules were performed. • Calculations were correlated with experiment on the molecules ground and excited states. • The general pattern of electron structure of chloroethylenes was obtained. • Necessity of this data for chloroethylenes negative ions study was noted. - Abstract: B3LYP/6-311 + G(d,p) calculations of ground and electronically excited states of ethylene, chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene-cis, 1,2-dichloroethylene-trans trichloroethylene and tetrachloroethylene molecules have been performed. Molecular orbitals images and orbital correlation diagram are given. The calculation results for chloroethylenes electronically excited states were compared with experimental data from the energy-loss spectra obtained and generally considered previously by C.F. Koerting, K.N. Walzl and A. Kupperman. Several new additional triplet and singlet transitions were pointed out in these spectra considering the calculation results. The finding of the additional transitions was supported by the UV absorption spectrum of trichloroethylene recorded in big cuvette (10 cm), where the first three triplet and two low-intensive forbidden singlet transitions were registered. The first triplet of this compound was recorded to be at the same energy as was found with the energy-loss spectroscopy.

  10. Electronic states of carbon alloy catalysts and nitrogen substituent effects on catalytic activity

    Science.gov (United States)

    Hata, Tomoyuki; Ushiyama, Hiroshi; Yamashita, Koichi

    2013-03-01

    In recent years, Carbon Alloy Catalysts (CACs) are attracting attention as a candidate for non-platinum-based cathode catalysts in fuel cells. Oxygen reduction reactions at the cathode are divided into two elementary processes, electron transfer and oxygen adsorption. The electron transfer reaction is the rate-determining, and by comparison of energy levels, catalytic activity can be evaluated quantitatively. On the other hand, to begin with, adsorption mechanism is obscure. The purpose of this study is to understand the effect of nitrogen substitution and oxygen adsorption mechanism, by first-principle electronic structure calculations for nitrogen substituted models. To reproduce the elementary processes of oxygen adsorption, we assumed that the initial structures are formed based on the Pauling model, a CACs model and nitrogen substituted CACs models in which various points are replaced with nitrogen. When we try to focus only on the DOS peaks of oxygen, in some substituted model that has high adsorption activity, a characteristic partial occupancy state was found. We conclude that this state will affect the adsorption activity, and discuss on why partially occupied states appear with simplification by using an orbital correlation diagram.

  11. Existence of ground state of an electron in the BDF approximation

    Science.gov (United States)

    Sok, Jérémy

    2014-05-01

    The Bogoliubov-Dirac-Fock (BDF) model allows us to describe relativistic electrons interacting with the Dirac sea. It can be seen as a mean-field approximation of Quantum Electrodynamics (QED) where photons are neglected. This paper treats the case of an electron together with the Dirac sea in the absence of any external field. Such a system is described by its one-body density matrix, an infinite rank, self-adjoint operator. The parameters of the model are the coupling constant α > 0 and the ultraviolet cut-off Λ > 0: we consider the subspace of squared integrable functions made of the functions whose Fourier transform vanishes outside the ball B(0, Λ). We prove the existence of minimizers of the BDF energy under the charge constraint of one electron and no external field provided that α, Λ-1 and α log(Λ) are sufficiently small. The interpretation is the following: in this regime the electron creates a polarization in the Dirac vacuum which allows it to bind. We then study the non-relativistic limit of such a system in which the speed of light tends to infinity (or equivalently α tends to zero) with αlog(Λ) fixed: after rescaling and translation the electronic solution tends to a Choquard-Pekar ground state.

  12. An experimental and theoretical investigation into the excited electronic states of phenol

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D. B.; Chiari, L. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Silva, G. B. da [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Universidade Federal de Mato Grosso, Barra do Garças, Mato Grosso (Brazil); Neves, R. F. C. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Departamento de Física, UFJF, Juiz de Fora, MG (Brazil); Instituto Federal do Sul de Minas Gerais, Campus Poços de Caldas, Minas Gerais (Brazil); Duque, H. V. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Departamento de Física, UFJF, Juiz de Fora, MG (Brazil); Oliveira, E. M. de; Lima, M. A. P. [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, 13083-859 Campinas, São Paulo (Brazil); Lopes, M. C. A. [Departamento de Física, UFJF, Juiz de Fora, MG (Brazil); Costa, R. F. da [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, 09210-580 Santo André, São Paulo (Brazil); Varella, M. T. do N. [Instituto de Física, Universidade de São Paulo, CP 66318, 05315-970 São Paulo (Brazil); Bettega, M. H. F. [Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-990 Curitiba, Paraná (Brazil); and others

    2014-08-21

    We present experimental electron-energy loss spectra (EELS) that were measured at impact energies of 20 and 30 eV and at angles of 90° and 10°, respectively, with energy resolution ∼70 meV. EELS for 250 eV incident electron energy over a range of angles between 3° and 50° have also been measured at a moderate energy resolution (∼0.9 eV). The latter spectra were used to derive differential cross sections and generalised oscillator strengths (GOS) for the dipole-allowed electronic transitions, through normalization to data for elastic electron scattering from benzene. Theoretical calculations were performed using time-dependent density functional theory and single-excitation configuration interaction methods. These calculations were used to assign the experimentally measured spectra. Calculated optical oscillator strengths were also compared to those derived from the GOS data. This provides the first investigation of all singlet and triplet excited electronic states of phenol up to the first ionization potential.

  13. Correlated electron state in CeCu2Si2 controlled through Si to P substitution

    Science.gov (United States)

    Lai, Y.; Saunders, S. M.; Graf, D.; Gallagher, A.; Chen, K.-W.; Kametani, F.; Besara, T.; Siegrist, T.; Shekhter, A.; Baumbach, R. E.

    2017-08-01

    CeCu2Si2 is an exemplary correlated electron metal that features two domes of unconventional superconductivity in its temperature-pressure phase diagram. The first dome surrounds an antiferromagnetic quantum critical point, whereas the more exotic second dome may span the termination point of a line of f -electron valence transitions. This behavior has received intense interest, but what has been missing are ways to access the high pressure behavior under milder conditions. Here we study Si → P chemical substitution, which compresses the unit cell volume but simultaneously weakens the hybridization between the f - and conduction electron states and encourages complex magnetism. At concentrations that show magnetism, applied pressure suppresses the magnetic ordering temperature and superconductivity is recovered for samples with low disorder. These results reveal that the electronic behavior in this system is controlled by a nontrivial combination of effects from unit cell volume and electronic shell filling. Guided by this topography, we discuss prospects for uncovering a valence fluctuation quantum phase transition in the broader family of Ce-based ThCr2Si2 -type materials through chemical substitution.

  14. Vibrational frequencies and dephasing times in excited electronic states by femtosecond time-resolved four-wave mixing

    Science.gov (United States)

    Joo, Taiha; Albrecht, A. C.

    1993-06-01

    Time-resolved degenerate four-wave mixing (TRDFWM) for an electronically resonant system in a phase-matching configuration that measures population decay is reported. Because the spectral width of input light exceeds the vibrational Bohr frequency of a strong Raman active mode, the vibrational coherence produces strong oscillations in the TRDFWM signal together with the usual population decay from the excited electronic state. The data are analyzed in terms of a four-level system: ground and excited electronic states each split by a vibrational quantum of a Raman active mode. Absolute frequencies and their dephasing times of the vibrational modes at ≈590 cm -1 are obtained for the excited as well as the ground electronic state. The vibrational dephasing rate in the excited electronic state is about an order of magnitude faster than that in the ground state, the origin of which is speculated upon.

  15. Multitudes of Stable States in a Periodically Driven Electron-Nuclear Spin System in a Quantum Dot

    OpenAIRE

    Korenev, V. L.

    2010-01-01

    The periodical modulation of circularly polarized light with a frequency close to the electron spin resonance frequency induces a sharp change of the single electron spin orientation. Hyperfine interaction provides a feedback, thus fixing the precession frequency of the electron spin in the external and the Overhauser field near the modulation frequency. The nuclear polarization is bidirectional and the electron-nuclear spin system (ENSS) possesses a few stable states. A similar frequency-loc...

  16. Structure-phase states evolution in Al-Si alloy under electron-beam treatment and high-cycle fatigue

    International Nuclear Information System (INIS)

    Konovalov, Sergey; Alsaraeva, Krestina; Gromov, Victor; Semina, Olga; Ivanov, Yurii

    2015-01-01

    By methods of scanning and transmission electron diffraction microscopy the analysis of structure-phase states and defect substructure of silumin subjected to high-intensity electron beam irradiation in various regimes and subsequent fatigue loading up to failure was carried out. It is revealed that the sources of fatigue microcracks are silicon plates of micron and submicron size are not soluble in electron beam processing. The possible reasons of the silumin fatigue life increase under electron-beam treatment are discussed

  17. Electronic state of ruthenium deposited onto oxide supports: An XPS study taking into account the final state effects

    International Nuclear Information System (INIS)

    Larichev, Yurii V.; Moroz, Boris L.; Bukhtiyarov, Valerii I.

    2011-01-01

    The electronic state of ruthenium in the supported Ru/EO x (EO x = MgO, Al 2 O 3 or SiO 2 ) catalysts prepared by with the use of Ru(OH)Cl 3 or Ru(acac) 3 (acac = acetylacetonate) and reduced with H 2 at 723 K is characterized by X-ray photoelectron spectroscopy (XPS) in the Ru 3d, Cl 2p and O 1s regions. The influence of the final state effects (the differential charging and variation of the relaxation energy) on the binding energy (BE) of Ru 3d 5/2 core level measured for supported Ru nanoparticles is estimated by comparison of the Fermi levels and the modified Auger parameters determined for the Ru/EO x samples with the corresponding characteristics of the bulk Ru metal. It is found that the negative shift of the Ru 3d 5/2 peak which is observed in the spectrum of ruthenium deposited onto MgO (BE = 279.5-279.7 eV) with respect to that of Ru black (BE = 280.2 eV) or ruthenium supported on γ-Al 2 O 3 and SiO 2 (BE = 280.4 eV) is caused not by the transfer of electron density from basic sites of MgO, as considered earlier, but by the differential charging of the supported Ru particles compared with the support surface. Correction for the differential charging value reveals that the initial state energies of ruthenium in the Ru/EO x systems are almost identical (BE = 280.5 ± 0.1 eV) irrespectively of acid-base properties of the support, the mean size of supported Ru crystallites (within the range of 2-10 nm) and the surface Cl content. The results obtained suggest that the difference in ammonia synthesis activity between the Ru catalysts supported on MgO and on the acidic supports is accounted for by not different electronic state of ruthenium on the surface of these oxides but by some other reasons.

  18. Tract- and county-level income inequality and individual risk of obesity in the United States.

    Science.gov (United States)

    Fan, Jessie X; Wen, Ming; Kowaleski-Jones, Lori

    2016-01-01

    We tested three alternative hypotheses regarding the relationship between income inequality and individual risk of obesity at two geographical scales: U.S. Census tract and county. Income inequality was measured by Gini coefficients, created from the 2000 U.S. Census. Obesity was clinically measured in the 2003-2008 National Health and Nutrition Examination Survey (NHANES). The individual measures and area measures were geo-linked to estimate three sets of multi-level models: tract only, county only, and tract and county simultaneously. Gender was tested as a moderator. At both the tract and county levels, higher income inequality was associated with lower individual risk of obesity. The size of the coefficient was larger for county-level Gini than for tract-level Gini; and controlling income inequality at one level did not reduce the impact of income inequality at the other level. Gender was not a significant moderator for the obesity-income inequality association. Higher tract and county income inequality was associated with lower individual risk of obesity, indicating that at least at the tract and county levels and in the context of cross-sectional data, the public health goal of reducing the rate of obesity is in line with anti-poverty policies of addressing poverty through mixed-income development where neighborhood income inequality is likely higher than homogeneous neighborhoods. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Cognitive benefit and cost of acute stress is differentially modulated by individual brain state

    NARCIS (Netherlands)

    Kohn, N.; Hermans, E.J.; Fernandez, G.

    2017-01-01

    Acute stress is associated with beneficial as well as detrimental effects on cognition in different individuals. However, it is not yet known how stress can have such opposing effects. Stroop-like tasks typically show this dissociation: stress diminishes speed, but improves accuracy. We investigated

  20. The separation of vibrational coherence from ground- and excited-electronic states in P3HT film

    International Nuclear Information System (INIS)

    Song, Yin; Hellmann, Christoph; Stingelin, Natalie; Scholes, Gregory D.

    2015-01-01

    Concurrence of the vibrational coherence and ultrafast electron transfer has been observed in polymer/fullerene blends. However, it is difficult to experimentally investigate the role that the excited-state vibrational coherence plays during the electron transfer process since vibrational coherence from the ground- and excited-electronic states is usually temporally and spectrally overlapped. Here, we performed 2-dimensional electronic spectroscopy (2D ES) measurements on poly(3-hexylthiophene) (P3HT) films. By Fourier transforming the whole 2D ES datasets (S(λ 1 ,T ~ 2 ,λ 3 )) along the population time (T ~ 2 ) axis, we develop and propose a protocol capable of separating vibrational coherence from the ground- and excited-electronic states in 3D rephasing and nonrephasing beating maps (S(λ 1 ,ν ~ 2 ,λ 3 )). We found that the vibrational coherence from pure excited electronic states appears at positive frequency (+ν ~ 2 ) in the rephasing beating map and at negative frequency (−ν ~ 2 ) in the nonrephasing beating map. Furthermore, we also found that vibrational coherence from excited electronic state had a long dephasing time of 244 fs. The long-lived excited-state vibrational coherence indicates that coherence may be involved in the electron transfer process. Our findings not only shed light on the mechanism of ultrafast electron transfer in organic photovoltaics but also are beneficial for the study of the coherence effect on photoexcited dynamics in other systems

  1. The separation of vibrational coherence from ground- and excited-electronic states in P3HT film

    KAUST Repository

    Song, Yin

    2015-06-07

    © 2015 AIP Publishing LLC. Concurrence of the vibrational coherence and ultrafast electron transfer has been observed in polymer/fullerene blends. However, it is difficult to experimentally investigate the role that the excited-state vibrational coherence plays during the electron transfer process since vibrational coherence from the ground- and excited-electronic states is usually temporally and spectrally overlapped. Here, we performed 2-dimensional electronic spectroscopy (2D ES) measurements on poly(3-hexylthiophene) (P3HT) films. By Fourier transforming the whole 2D ES datasets (S (λ 1, T∼ 2, λ 3)) along the population time (T∼ 2) axis, we develop and propose a protocol capable of separating vibrational coherence from the ground- and excited-electronic states in 3D rephasing and nonrephasing beating maps (S (λ 1, ν∼ 2, λ 3)). We found that the vibrational coherence from pure excited electronic states appears at positive frequency (+ ν∼ 2) in the rephasing beating map and at negative frequency (- ν∼ 2) in the nonrephasing beating map. Furthermore, we also found that vibrational coherence from excited electronic state had a long dephasing time of 244 fs. The long-lived excited-state vibrational coherence indicates that coherence may be involved in the electron transfer process. Our findings not only shed light on the mechanism of ultrafast electron transfer in organic photovoltaics but also are beneficial for the study of the coherence effect on photoexcited dynamics in other systems.

  2. Bulk and interface quantum states of electrons in multi-layer heterostructures with topological materials

    Science.gov (United States)

    Nikolic, Aleksandar; Zhang, Kexin; Barnes, C. H. W.

    2018-06-01

    In this article we describe the bulk and interface quantum states of electrons in multi-layer heterostructures in one dimension, consisting of topological insulators (TIs) and topologically trivial materials. We use and extend an effective four-band continuum Hamiltonian by introducing position dependence to the eight material parameters of the Hamiltonian. We are able to demonstrate complete conduction-valence band mixing in the interface states. We find evidence for topological features of bulk states of multi-layer TI heterostructures, as well as demonstrating both complete and incomplete conduction-valence band inversion at different bulk state energies. We show that the linear k z terms in the low-energy Hamiltonian, arising from overlap of p z orbitals between different atomic layers in the case of chalcogenides, control the amount of tunneling from TIs to trivial insulators. Finally, we show that the same linear k z terms in the low-energy Hamiltonian affect the material’s ability to form the localised interface state, and we demonstrate that due to this effect the spin and probability density localisation in a thin film of Sb2Te3 is incomplete. We show that changing the parameter that controls the magnitude of the overlap of p z orbitals affects the transport characteristics of the topologically conducting states, with incomplete topological state localisation resulting in increased backscattering.

  3. Charge-state dependence of binary-encounter-electron cross sections and peak energies

    International Nuclear Information System (INIS)

    Hidmi, H.I.; Richard, P.; Sanders, J.M.; Schoene, H.; Giese, J.P.; Lee, D.H.; Zouros, T.J.M.; Varghese, S.L.

    1993-01-01

    The charge-state dependence of the binary-encounter-electron (BEE) double-differential cross section (DDCS) at 0 degree with respect to the beam direction resulting from collisions of 1 MeV/amu H + , C q+ , N q+ , O q+ , F q+ , Si q+ , and Cl q+ , and 0.5 MeV/amu Cu q+ with H 2 is reported. The data show an enhancement in the BEE DDCS as the charge state of the projectile is decreased, in agreement with the data reported by Richard et al. [J. Phys. B 23, L213 (1990)]. The DDCS enhancement ratios observed for the three-electron isoelectronic sequence C 3+ :C 6+ , N 4+ :N 7+ , O 5+ :O 8+ , and F 6+ :F 9+ are about 1.35, whereas a DDCS enhancement of 3.5 was observed for Cu 4+ . The BEE enhancement with increasing electrons on the projectile has been shown by several authors to be due to the non-Coulomb static potential of the projectile and additionally to the e-e exchange interaction. An impulse-approximation (IA) model fits the shape of the BEE DDCS and predicts a Z p 2 dependence for the bare-ion cross sections. The IA also predicts a binary peak energy that is independent of q and Z p and below the classical value of 4t, where t is the energy of electrons traveling with the projectile velocity. We observed a BEE energy shift ΔE (ΔE=4t-E peak , where E peak is the measured energy at the peak of the binary encounter electrons) that is approximately independent of q for the low-Z p ions, whereas the measured ΔE values for Si, Cl, and Cu were found to be q dependent

  4. Spectroscopy of weakly-bound complexes in highly excited electronic states: the He-I2(E3Πg) ion-pair state

    International Nuclear Information System (INIS)

    Prosmiti, Rita; Valdés, Álvaro; Kalemost, Apostolos

    2014-01-01

    The study of electronically excited van der Waals (vdW) systems presents a challenge for the theory of intermolecular interactions, and here we show how far ab initio computations can go. We found that the interaction energies for such electronically excited systems can indeed be determined, providing a reliable and accurate description for the E state potential of the HeI 2 , that in combination with the ground X and electronic excited B state of the complex, is useful to model experimental data related with potential minima and also predict higher vibrational vdW states

  5. Mapping Catalytically Relevant Edge Electronic States of MoS2

    Science.gov (United States)

    2018-01-01

    Molybdenum disulfide (MoS2) is a semiconducting transition metal dichalcogenide that is known to be a catalyst for both the hydrogen evolution reaction (HER) as well as for hydro-desulfurization (HDS) of sulfur-rich hydrocarbon fuels. Specifically, the edges of MoS2 nanostructures are known to be far more catalytically active as compared to unmodified basal planes. However, in the absence of the precise details of the geometric and electronic structure of the active catalytic sites, a rational means of modulating edge reactivity remain to be developed. Here we demonstrate using first-principles calculations, X-ray absorption spectroscopy, as well as scanning transmission X-ray microscopy (STXM) imaging that edge corrugations yield distinctive spectroscopic signatures corresponding to increased localization of hybrid Mo 4d states. Independent spectroscopic signatures of such edge states are identified at both the S L2,3 and S K-edges with distinctive spatial localization of such states observed in S L2,3-edge STXM imaging. The presence of such low-energy hybrid states at the edge of the conduction band is seen to correlate with substantially enhanced electrocatalytic activity in terms of a lower Tafel slope and higher exchange current density. These results elucidate the nature of the edge electronic structure and provide a clear framework for its rational manipulation to enhance catalytic activity. PMID:29721532

  6. Defect induced electronic states and magnetism in ball-milled graphite.

    Science.gov (United States)

    Milev, Adriyan; Dissanayake, D M A S; Kannangara, G S K; Kumarasinghe, A R

    2013-10-14

    The electronic structure and magnetism of nanocrystalline graphite prepared by ball milling of graphite in an inert atmosphere have been investigated using valence band spectroscopy (VB), core level near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and magnetic measurements as a function of the milling time. The NEXAFS spectroscopy of graphite milled for 30 hours shows simultaneous evolution of new states at ~284.0 eV and at ~290.5 eV superimposed upon the characteristic transitions at 285.4 eV and 291.6 eV, respectively. The modulation of the density of states is explained by evolution of discontinuities within the sheets and along the fracture lines in the milled graphite. The magnetic measurements in the temperature interval 2-300-2 K at constant magnetic field strength show a correlation between magnetic properties and evolution of the new electronic states. With the reduction of the crystallite sizes of the graphite fragments, the milled material progressively changes its magnetic properties from diamagnetic to paramagnetic with contributions from both Pauli and Curie paramagnetism due to the evolution of new states at ~284 and ~290.5 eV, respectively. These results indicate that the magnetic behaviour of ball-milled graphite can be manipulated by changing the milling conditions.

  7. Electronic relaxation of deep bulk trap and interface state in ZnO ceramics

    International Nuclear Information System (INIS)

    Yang Yan; Li Sheng-Tao; Ding Can; Cheng Peng-Fei

    2011-01-01

    This paper investigates the electronic relaxation of deep bulk trap and interface state in ZnO ceramics based on dielectric spectra measured in a wide range of temperature, frequency and bias, in addition to the steady state response. It discusses the nature of net current flowing over the barrier affected by interface state, and then obtains temperature-dependent barrier height by approximate calculation from steady I—V (current—voltage) characteristics. Additional conductance and capacitance arising from deep bulk trap relaxation are calculated based on the displacement of the cross point between deep bulk trap and Fermi level under small AC signal. From the resonances due to deep bulk trap relaxation on dielectric spectra, the activation energies are obtained as 0.22 eV and 0.35 eV, which are consistent with the electronic levels of the main defect interstitial Zn and vacancy oxygen in the depletion layer. Under moderate bias, another resonance due to interface relaxation is shown on the dielectric spectra. The DC-like conductance is also observed in high temperature region on dielectric spectra, and the activation energy is much smaller than the barrier height in steady state condition, which is attributed to the displacement current coming from the shallow bulk trap relaxation or other factors. (fluids, plasmas and electric discharges)

  8. Excitation and characterization of image potential state electrons on quasi-free-standing graphene

    Science.gov (United States)

    Lin, Yi; Li, Yunzhe; Sadowski, Jerzy T.; Jin, Wencan; Dadap, Jerry I.; Hybertsen, Mark S.; Osgood, Richard M.

    2018-04-01

    We investigate the band structure of image potential states in quasi-free-standing graphene (QFG) monolayer islands using angle-resolved two-photon-photoemission spectroscopy. Direct probing by low-energy electron diffraction shows that QFG is formed following oxygen intercalation into the graphene-Ir(111) interface. Despite the apparent decoupling of the monolayer graphene from the Ir substrate, we find that the binding energy of the n =1 image potential state on these QFG islands increases by 0.17 eV, as compared to the original Gr/Ir(111) interface. We use calculations based on density-functional theory to construct an empirical, one-dimensional potential that quantitatively reproduces the image potential state binding energy and links the changes in the interface structure to the shift in energy. Specifically, two factors contribute comparably to this energy shift: a deeper potential well arising from the presence of intercalated oxygen adatoms and a wider potential well associated with the increase in the graphene-Ir distance. While image potential states have not been observed previously on QFG by photoemission, our paper now demonstrates that they may be strongly excited in a well-defined QFG system produced by oxygen intercalation. This opens an opportunity for studying the surface electron dynamics in QFG systems, beyond those found in typical nonintercalated graphene-on-substrate systems.

  9. Real-space Mapping of Surface Trap States in CIGSe Nanocrystals using 4D Electron Microscopy

    KAUST Repository

    Bose, Riya

    2016-05-26

    Surface trap states in semiconductor copper indium gallium selenide nanocrystals (NCs) which serve as undesirable channels for non-radiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with sub-picosecond temporal and nanometer spatial resolutions. Here, we precisely map the surface charge carrier dynamics of copper indium gallium selenide NCs before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs.

  10. Real-space Mapping of Surface Trap States in CIGSe Nanocrystals using 4D Electron Microscopy

    KAUST Repository

    Bose, Riya; Bera, Ashok; Parida, Manas R.; Adhikari, Aniruddha; Shaheen, Basamat; Alarousu, Erkki; Sun, Jingya; Wu, Tao; Bakr, Osman; Mohammed, Omar F.

    2016-01-01

    Surface trap states in semiconductor copper indium gallium selenide nanocrystals (NCs) which serve as undesirable channels for non-radiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with sub-picosecond temporal and nanometer spatial resolutions. Here, we precisely map the surface charge carrier dynamics of copper indium gallium selenide NCs before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs.

  11. SUPRATHERMAL ELECTRONS IN THE SOLAR CORONA: CAN NONLOCAL TRANSPORT EXPLAIN HELIOSPHERIC CHARGE STATES?

    International Nuclear Information System (INIS)

    Cranmer, Steven R.

    2014-01-01

    There have been several ideas proposed to explain how the Sun's corona is heated and how the solar wind is accelerated. Some models assume that open magnetic field lines are heated by Alfvén waves driven by photospheric motions and dissipated after undergoing a turbulent cascade. Other models posit that much of the solar wind's mass and energy is injected via magnetic reconnection from closed coronal loops. The latter idea is motivated by observations of reconnecting jets and also by similarities of ion composition between closed loops and the slow wind. Wave/turbulence models have also succeeded in reproducing observed trends in ion composition signatures versus wind speed. However, the absolute values of the charge-state ratios predicted by those models tended to be too low in comparison with observations. This Letter refines these predictions by taking better account of weak Coulomb collisions for coronal electrons, whose thermodynamic properties determine the ion charge states in the low corona. A perturbative description of nonlocal electron transport is applied to an existing set of wave/turbulence models. The resulting electron velocity distributions in the low corona exhibit mild suprathermal tails characterized by ''kappa'' exponents between 10 and 25. These suprathermal electrons are found to be sufficiently energetic to enhance the charge states of oxygen ions, while maintaining the same relative trend with wind speed that was found when the distribution was assumed to be Maxwellian. The updated wave/turbulence models are in excellent agreement with solar wind ion composition measurements

  12. States with stronger health insurance rate review authority experienced lower premiums in the individual market in 2010-13.

    Science.gov (United States)

    Karaca-Mandic, Pinar; Fulton, Brent D; Hollingshead, Ann; Scheffler, Richard M

    2015-08-01

    States have varying degrees of review authority over health insurance carriers' rates, including prior approval authority over proposed rates and requirements for loss ratios, the proportion of premium revenues spent on medical claims. The Affordable Care Act (ACA) requires carriers in certain categories of health insurance to provide public justification for rate increases of 10 percent or more. We collected data on how states changed their rate review authority and requirements during 2010-13, the years immediately after enactment of the ACA, and we combined these data with carrier filings. We found that adjusted premiums in the individual market in states that had prior-approval authority combined with loss ratio requirements were lower in 2010-13 ($3,489) than premiums in states with no rate review authority or that had only file-and-use regulations, which gave the states no authority to block rate increases ($3,617). Adjusted premiums declined modestly in prior-approval states with loss ratio requirements, from $3,526 in 2010 to $3,452 in 2013, while premiums increased from $3,422 to $3,683 in states with no rate review authority or file-and-use regulations only. Our findings suggest that states with prior approval authority and loss ratio requirements constrained health insurance premium increases. Project HOPE—The People-to-People Health Foundation, Inc.

  13. Individualized fracture risk assessment: State-of-the-art and room for improvement

    Directory of Open Access Journals (Sweden)

    Tuan V. Nguyen

    2018-03-01

    Full Text Available Fragility fracture is a serious clinical event, because it is associated with increased risk of mortality and reduced quality of life. The risk of fracture is determined by multiple risk factors, and their effects may be interactional. Over the past 10 years, a number of predictive models (e.g., FRAX, Garvan Fracture Risk Calculator, and Qfracture have been developed for individualized assessment of fracture risk. These models use different risk profiles to estimate the probability of fracture over 5- and 10-year period. The ability of these models to discriminate between those individuals who will and will not have a fracture (i.e., area under the receiver operating characteristic curve [AUC] is generally acceptable-to-good (AUC, 0.6 to 0.8, and is highly variable between populations. The calibration of existing models is poor, particularly in Asian populations. There is a strong need for the development and validation of new prediction models based on Asian data for Asian populations. We propose approaches to improve the accuracy of existing predictive models by incorporating new markers such as genetic factors, bone turnover markers, trabecular bone score, and time-variant factors. New and more refined models for individualized fracture risk assessment will help identify those most likely to sustain a fracture, those most likely to benefit from treatment, and encouraging them to modify their risk profile to decrease risk. Keywords: Osteoporosis, Fracture, Fracture risk assessment, Genetic profiling, FRAX, Garvan

  14. Electronic properties of excited states in single InAs quantum dots

    International Nuclear Information System (INIS)

    Warming, Till

    2009-01-01

    The application of quantum-mechanical effects in semiconductor nanostructures enables the realization of novel opto-electronic devices. Examples are given by single-photon emitters and emitters of entangled photon pairs, both being essential for quantum cryptography, or for qubit systems as needed for quantum computing. InAs/GaAs quantum dots are one of the most promising candidates for such applications. A detailed knowledge of the electronic properties of quantum dots is a prerequisite for this development. The aim of this work is an experimental access to the detailed electronic structure of the excited states in single InAs/GaAs quantum dots including few-particle effects and in particular exchange interaction. The experimental approach is micro photoluminescence excitation spectroscopy (μPLE). One of the main difficulties using μPLE to probe single QDs is the unambiguous assignment of the observed resonances in the spectrum to specific transitions. By comparing micro photoluminescence (μPL) and μPLE spectra, the identification of the main resonances becomes possible. The key is given by the fine structure of the hot trion. Excitation spectroscopy on single charged QDs enables for the first time the complete observation of a non-trivial fine structure of an excitonic complex in a QD, the hot trion. Modelling based on eight-band k.p theory in combination with a configuration interaction scheme is in excellent agreement. Therewith the simulation also enables realistic predictions on the fine structure of the ground-state exciton which is of large importance for single quantum dot devices. Theory concludes from the observed transitions that the structural symmetry of the QDs is broken. Micro photoluminescence excitation spectroscopy combined with resonantly excited micro photoluminescence enables an optical access to the single particle states of the hole without the influence of few-particle coulomb interactions. Based on this knowledge the exciton binding

  15. Measurement of Electronic States of PbS Nanocrystal Quantum Dots Using Scanning Tunneling Spectroscopy: The Role of Parity Selection Rules in Optical Absorption

    Science.gov (United States)

    Diaconescu, Bogdan; Padilha, Lazaro A.; Nagpal, Prashant; Swartzentruber, Brian S.; Klimov, Victor I.

    2013-03-01

    We study the structure of electronic states in individual PbS nanocrystal quantum dots by scanning tunneling spectroscopy (STS) using one-to-two monolayer nanocrystal films treated with 1, 2-ethanedithiols (EDT). Up to six individual valence and conduction band states are resolved for a range of quantum dot sizes. The measured states’ energies are in good agreement with calculations using the k·p four-band envelope function formalism. A comparison of STS and optical absorption spectra indicates that some of the absorption features can only be explained by asymmetric transitions involving the states of different symmetries (e.g., S and P or P and D), which points towards the relaxation of the parity selection rules in these nanostructures. STS measurements also reveal a midgap feature, which is likely similar to one observed in previous charge transport studies of EDT-treated quantum dot films.

  16. Cancer treatment disparities in HIV-infected individuals in the United States.

    Science.gov (United States)

    Suneja, Gita; Shiels, Meredith S; Angulo, Rory; Copeland, Glenn E; Gonsalves, Lou; Hakenewerth, Anne M; Macomber, Kathryn E; Melville, Sharon K; Engels, Eric A

    2014-08-01

    HIV-infected individuals with cancer have worse survival rates compared with their HIV-uninfected counterparts. One explanation may be differing cancer treatment; however, few studies have examined this. We used HIV and cancer registry data from Connecticut, Michigan, and Texas to study adults diagnosed with non-Hodgkin's lymphoma, Hodgkin's lymphoma, or cervical, lung, anal, prostate, colorectal, or breast cancers from 1996 to 2010. We used logistic regression to examine associations between HIV status and cancer treatment, adjusted for cancer stage and demographic covariates. For a subset of local-stage cancers, we used logistic regression to assess the relationship between HIV status and standard treatment modality. We identified predictors of cancer treatment among individuals with both HIV and cancer. We evaluated 3,045 HIV-infected patients with cancer and 1,087,648 patients with cancer without HIV infection. A significantly higher proportion of HIV-infected individuals did not receive cancer treatment for diffuse large B-cell lymphoma (DLBCL; adjusted odds ratio [aOR], 1.67; 95% CI, 1.41 to 1.99), lung cancer (aOR, 2.18; 95% CI, 1.80 to 2.64), Hodgkin's lymphoma (aOR, 1.77; 95% CI, 1.33 to 2.37), prostate cancer (aOR, 1.79; 95% CI, 1.31 to 2.46), and colorectal cancer (aOR, 2.27; 95% CI, 1.38 to 3.72). HIV infection was associated with a lack of standard treatment modality for local-stage DLBCL (aOR, 2.02; 95% CI, 1.50 to 2.72), non-small-cell lung cancer (aOR, 2.43; 95% CI, 1.46 to 4.03), and colon cancer (aOR, 4.77; 95% CI, 1.76 to 12.96). Among HIV-infected individuals, factors independently associated with lack of cancer treatment included low CD4 count, male sex with injection drug use as mode of HIV exposure, age 45 to 64 years, black race, and distant or unknown cancer stage. HIV-infected individuals are less likely to receive treatment for some cancers than uninfected people, which may affect survival rates. © 2014 by American Society of Clinical

  17. Recent advances in the 5f-relevant electronic states and unconventional superconductivity of actinide compounds

    International Nuclear Information System (INIS)

    Haga, Yoshinori; Sakai, Hironori; Kambe, Shinsaku

    2007-01-01

    Recent advances in the understanding of the 5f-relevant electronic states and unconventional superconducting properties are reviewed in actinide compounds of UPd 2 Al 3 . UPt 3 , URu 2 Si 2 , UGe 2 , and PuRhGa 5 . These are based on the experimental results carried out on high-quality single crystal samples, including transuranium compounds, which were grown by using combined techniques. The paring state and the gap structure of these superconductors are discussed, especially for the corresponding Fermi surfaces which were clarified by the de Haas-van Alphen experiment and the energy band calculations. A detailed systematic study using the NQR/NMR spectroscopy reveals the d-wave superconductivity in PuRhGa 5 and the difference of magnetic excitations due to the difference of ground states in U-, Np-, and Pu-based AnTGa 5 (T: transition metal) compounds. (author)

  18. Perpendicular State of an Electronically Excited Stilbene: Observation by Femtosecond-Stimulated Raman Spectroscopy.

    Science.gov (United States)

    Quick, Martin; Dobryakov, Alexander L; Ioffe, Ilya N; Granovsky, Alex A; Kovalenko, Sergey A; Ernsting, Nikolaus P

    2016-10-20

    In the photoisomerization path of stilbene, a perpendicular state P on the S 1 potential energy surface is expected just before internal conversion through a conical intersection S 1 /S 0 . For decades the observation of P was thwarted by a short lifetime τ P in combination with slow population flow over a barrier. But these limitations can be overcome by ethylenic substitution. Following optical excitation of trans-1,1'-dicyanostilbene, P is populated significantly (τ P = 27 ps in n-hexane) and monitored by an exited-state absorption band at 370 nm. Here we report stimulated Raman lines of P. The strongest, at 1558 cm -1 , is attributed to stretching vibrations of the phenyl rings. Transient electronic states, resonance conditions, and corresponding Raman signals are discussed.

  19. Electron states in quantum rings with structural distortions under axial or in-plane magnetic fields

    International Nuclear Information System (INIS)

    Planelles, J; Rajadell, F; Climente, J I

    2007-01-01

    A comprehensive study of anisotropic quantum rings, QRs, subject to axial and in-plane magnetic field, both aligned and transverse to the anisotropy direction, is carried out. Elliptical QRs for a wide range of eccentricity values and also perfectly circular QRs including one or more barriers disturbing the QR current are considered. These models mimic anisotropic geometry deformations and mass diffusion occurring in the QR fabrication process. Symmetry considerations and simplified analytical models supply physical insight into the obtained numerical results. Our study demonstrates that, except for unusual extremely large eccentricities, QR geometry deformations only appreciably influence a few low-lying states, while the effect of barriers disturbing the QR current is stronger and affects all studied states to a similar extent. We also show that the response of the electron states to in-plane magnetic fields provides accurate information on the structural anisotropy

  20. Multifractal character of the electronic states in disordered two-dimensional systems

    International Nuclear Information System (INIS)

    Tit, N.; Schreiber, M.

    1994-08-01

    The nature of electronic states in disordered two-dimensional (2D) systems is investigated. To this aim, we present our calculations of both density of states and dc-conductivity for square lattices modelling the Anderson Hamiltonian with on-site energies randomly chosen from a box distribution of width W. For weak disorder (W), the eigenfunctions calculated by means of the Lanczos diagonalization algorithm display spatial fluctuations reflecting their (multi)fractal behaviour. For increasing disorder or energy the observed increase of the curdling of the wavefunction reflects its stronger localization. Our dc-conductivity results suggest a critical fractal dimension d * c =1.48±0.05 to discriminate between the exponentially and the power-law localized states. Consequences of the localization on transport properties are also discussed. (author). 30 refs, 10 figs, 1 tab

  1. Initial state dependence of nonlinear kinetic equations: The classical electron gas

    International Nuclear Information System (INIS)

    Marchetti, M.C.; Cohen, E.G.D.; Dorfman, J.R.; Kirkpatrick, T.R.

    1985-01-01

    The method of nonequilibrium cluster expansion is used to study the decay to equilibrium of a weakly coupled inhomogeneous electron gas prepared in a local equilibrium state at the initial time, t=0. A nonlinear kinetic equation describing the long time behavior of the one-particle distribution function is obtained. For consistency, initial correlations have to be taken into account. The resulting kinetic equation-differs from that obtained when the initial state of the system is assumed to be factorized in a product of one-particle functions. The question of to what extent correlations in the initial state play an essential role in determining the form of the kinetic equation at long times is discussed. To that end, the present calculations are compared wih results obtained before for hard sphere gases and in general with strong short-range forces. A partial answer is proposed and some open questions are indicated

  2. 78 FR 17882 - Recreational Closure Authority Specific to Federal Waters Off Individual States for the...

    Science.gov (United States)

    2013-03-25

    ... support of this emergency rule, which include an environmental assessment, may be obtained from the... Louisiana and Florida have recently indicated they will implement inconsistent recreational red snapper... reductions would be needed if other Gulf states (Mississippi and Alabama) also implement inconsistent...

  3. Individuals with Mental Retardation and the Criminal Justice System: The View from States' Attorneys General.

    Science.gov (United States)

    McAfee, James K.; Gural, Michele

    1988-01-01

    Results of a survey of state attorneys general (N=46) found that, with few exceptions, identification of persons with mental retardation in criminal justice is neither systematic nor probable. Protections lie in statutes pertaining to mental illness rather than to mental retardation. (Author/DB)

  4. Insular Activity during Passive Viewing of Aversive Stimuli Reflects Individual Differences in State Negative Affect

    Science.gov (United States)

    Meriau, Katja; Wartenburger, Isabell; Kazzer, Philipp; Prehn, Kristin; Villringer, Arno; van der Meer, Elke; Heekeren, Hauke R.

    2009-01-01

    People differ with regard to how they perceive, experience, and express negative affect. While trait negative affect reflects a stable, sustained personality trait, state negative affect represents a stimulus limited and temporally acute emotion. So far, little is known about the neural systems mediating the relationship between negative affect…

  5. Present status of practical aspects of individual dosimetry. Pt. 1. EC Member States

    International Nuclear Information System (INIS)

    Goeksu, H.Y.; Regulla, D.; Drexler, G.

    1995-01-01

    The study reviews the present status of radiation protection practices of occupationally exposed persons in the Member States of the European Communities by taking account of the new legislative changes. A special emphasis is given to identify and describe the difference in procedures and methods of personnel monitoring, dose assessment, record keeping and collective dose assessment in each country. (orig./HP)

  6. Potential curves and spectroscopic study of the electronic states of the molecular ion LiCs+

    International Nuclear Information System (INIS)

    Moughrabi, A.; Korek, M.; Allouche, A.R.

    2004-01-01

    Full text.Due to a very accurate high-resolution techniques and to the spectacular developments in ultracold alkali atom trapping developments which are at the root of photo association spectroscopy there has been a renewed interest on the spectroscopic study of alkali dimers. The existence of new experimental data on these species has stimulated theoretical approaches, necessary to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. With the aim of improving the accuracy of predictions we will perform a theoretical study of the electronic structure of the molecular ion LiCs + , using a method mainly in the way by which core-valence effects are taken into account. To investigate the electronic structure of LiCs + we will use the package CIPSI (Configuration Interaction by Perturbation of a multiconfiguration wave function Selected Interactively) of the Laboratoire de Physique Quantique (Toulouse, France). The atoms Li and Cs will be treated through non-empirical effective one electron core potentials of Durand and Barthelat type. Molecular orbitals for LiCs + will be derived from Self Consistent Field Calculations (SCF) and full valence Configuration Interaction (IC) calculations. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. Potential energy calculations will be performed for different molecular states, for numerous values of the inter-nuclear distance R in a wide range. Spectroscopic constants have been derived for the bound states with a regular shape A ro vibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants. A calculation for the transition dipole moment and matrix elements have been done for the bound states

  7. The reliability of assigning individuals to cognitive states using the Mini Mental-State Examination: a population-based prospective cohort study

    Directory of Open Access Journals (Sweden)

    Brayne Carol

    2011-09-01

    Full Text Available Abstract Background Previous investigations of test re-test reliability of the Mini-Mental State Examination (MMSE have used correlations and statistics such as Cronbach's α to assess consistency. In practice, the MMSE is usually used to group individuals into cognitive states. The reliability of this grouping (state based approach has not been fully explored. Methods MMSE data were collected on a subset of 2,275 older participants (≥ 65 years from the population-based Medical Research Council Cognitive Function and Ageing Study. Two measurements taken approximately two months apart were used to investigate three state-based categorisations. Descriptive statistics were used to determine how many people remained in the same cognitive group or went up or down groups. Weighted logistic regression was used to identify predictive characteristics of those who moved group. Results The proportion of people who remained in the same MMSE group at screen and follow-up assessment ranged from 58% to 78%. The proportion of individuals who went up one or more groups was roughly equal to the proportion that went down one or more groups; most of the change occurred when measurements were close to the cut-points. There was no consistently significant predictor for changing cognitive group. Conclusion A state-based approach to analysing the reliability of the MMSE provided similar results to correlation analyses. State-based models of cognitive change or individual trajectory models using raw scores need multiple waves to help overcome natural variation in MMSE scores and to help identify true cognitive change.

  8. Dynamic Electron Correlation Effects on the Ground State Potential Energy Surface of a Retinal Chromophore Model.

    Science.gov (United States)

    Gozem, Samer; Huntress, Mark; Schapiro, Igor; Lindh, Roland; Granovsky, Alexander A; Angeli, Celestino; Olivucci, Massimo

    2012-11-13

    The ground state potential energy surface of the retinal chromophore of visual pigments (e.g., bovine rhodopsin) features a low-lying conical intersection surrounded by regions with variable charge-transfer and diradical electronic structures. This implies that dynamic electron correlation may have a large effect on the shape of the force fields driving its reactivity. To investigate this effect, we focus on mapping the potential energy for three paths located along the ground state CASSCF potential energy surface of the penta-2,4-dieniminium cation taken as a minimal model of the retinal chromophore. The first path spans the bond length alternation coordinate and intercepts a conical intersection point. The other two are minimum energy paths along two distinct but kinetically competitive thermal isomerization coordinates. We show that the effect of introducing the missing dynamic electron correlation variationally (with MRCISD) and perturbatively (with the CASPT2, NEVPT2, and XMCQDPT2 methods) leads, invariably, to a stabilization of the regions with charge transfer character and to a significant reshaping of the reference CASSCF potential energy surface and suggesting a change in the dominating isomerization mechanism. The possible impact of such a correction on the photoisomerization of the retinal chromophore is discussed.

  9. Theoretical study of the electronic structure of different states of the KRb+ molecular ion

    International Nuclear Information System (INIS)

    Korek, M.; Younis, G.

    2000-01-01

    Full text.The molecular activities in ultra-cold alkali atom trapping stimulate theoretical developments to compute relevant adiabatic potential curves, especially in the framework of the pseudopotential methods. For these methods the molecular ion KRb+ is treated as system with one active electron moving in a field of two ionic cores, where core valence electron interactions are presented by an effective potential. Potential energies have been calculated over a wide range of internuclear distance (5.0-60a o ) for the lowest states of symmetry 2 Σ, 2 Π, 2 Δ and Ω for the molecular ion KRb+. To avoid an over estimation of the dissociation energy the perturbative treatment is replaced by an l-dependent core-polarization potential of the Foucrault et al. For the one valence electron of the two considered atoms, we recalculated the polarization potential cut-off parameters r k l , and r R b l by taking l=0,1,2 and r i 2 =r i 3 . Molecular orbital for the molecular ion KRb+ were derived from Self Consistent Field calculations (SCF), and full valence Configuration Interaction (IC) calculations were performed. Extensive tables of energy values versus internuclear distance are displayed and molecular spectroscopic constants have been derived, for the first time, for the bound states with regular shape

  10. INFLUENCE OF THE SKELETON HIERARCHICAL ORGANIZATION ON ELECTRONIC STATE OF IONS IN BONE MATRIX

    Directory of Open Access Journals (Sweden)

    A. S. Avrunin

    2016-01-01

    Full Text Available The authors suggested the 3D-superlattice (3DSL model to describe the effect of coplanar assembly of the hydroxyapatite (HA nanocrystallites on local electronic state of ions in mineralized bone. This model is based on the main structural and functional relationships between adjacent levels of the hierarchical organization of bone tissue. In the framework of the 3DSL model the authors predicted the distinct assembly-to-crystal red shift of the unoccupied electronic states located near the bottom of the conduction band in HA and dependence of this shift on the ratio of the thickness of the hydrated layer to the crystallite size. To check these predictions the experimental X-ray absorption studies of native bone are performed near the Ca2р1/2,3/2-, P2р1/2,3/2- и O1s edges. Comparison of the measured spectra with the known spectra of the reference compounds has confirmed appearance of the distinct assembly-to-crystal red shift. The observed effect is the ground for development of new diagnostic methods for bone status and imaging changes in the local electronic structure of bone tissue by using ultrasoft X-ray absorption spectroscopy and measuring the assembly-tocrystal shifts. The experimental data analysis proved the applicability of the 3DSL model for better understanding of the hierarchical organization of bone at nanolevel.

  11. Superatom spectroscopy and the electronic state correlation between elements and isoelectronic molecular counterparts.

    Science.gov (United States)

    Peppernick, Samuel J; Gunaratne, K D Dasitha; Castleman, A W

    2010-01-19

    Detailed in the present investigation are results pertaining to the photoelectron spectroscopy of negatively charged atomic ions and their isoelectronic molecular counterparts. Experiments utilizing the photoelectron imaging technique are performed on the negative ions of the group 10 noble metal block (i.e. Ni-, Pd-, and Pt-) of the periodic table at a photon energy of 2.33 eV (532 nm). The accessible electronic transitions, term energies, and orbital angular momentum components of the bound electronic states in the atom are then compared with photoelectron images collected for isoelectronic early transition metal heterogeneous diatomic molecules, M-X- (M = Ti,Zr,W; X = O or C). A superposition principle connecting the spectroscopy between the atomic and molecular species is observed, wherein the electronic structure of the diatomic is observed to mimic that present in the isoelectronic atom. The molecular ions studied in this work, TiO-, ZrO-, and WC- can then be interpreted as possessing superatomic electronic structures reminiscent of the isoelectronic elements appearing on the periodic table, thereby quantifying the superatom concept.

  12. Low levels of maximal aerobic power impair the profile of mood state in individuals with temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Rodrigo Luiz Vancini

    2015-01-01

    Full Text Available Objective To investigate the correlation between cardiorespiratory fitness and mood state in individuals with temporal lobe epilepsy (TLE. Method Individuals with TLE (n = 20 and healthy control subjects (C, n = 20 were evaluated. Self-rating questionnaires were used to assess mood (POMS and habitual physical activity (BAECKE. Cardiorespiratory fitness was evaluated by a maximal incremental test. Results People with TLE presented lower cardiorespiratory fitness; higher levels of mood disorders; and lower levels of vigor when compared to control health subjects. A significant negative correlation was observed between the levels of tension-anxiety and maximal aerobic power. Conclusion Low levels of cardiorespiratory fitness may modify the health status of individuals with TLE and it may be considered a risk factor for the development of mood disorders.

  13. Modelling individual preferences, State of the art, recent advances and future directions

    DEFF Research Database (Denmark)

    Cherchi, Elisabetta

    2012-01-01

    Fadden, 1999). The reason for this dominance is that economic theory has provided an elegant, rigorous and at the same time relatively easy to implement model, designed to describe individuals’ decisions and to provide quantitative forecasts with well-defined statistical properties. On the other hand, although...... limitations in the capability of microeconomic theory to explain individual choices and that we are still far from having a satisfactory representation (through known variables) of the real phenomenon. In fact, although RUM “takes a nod towards psychological theory” (Batley and Daly, 2006), the error term...

  14. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Five: Relationships of Current, Voltage, and Resistance. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on the relationships of current, voltage, and resistance is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptaticn to vocational instructional and curriculum development in a civilian setting.…

  15. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Fourteen: Parallel AC Resistive-Reactive Circuits. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on parallel alternating current resistive-reaction circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian…

  16. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Six: Parallel Circuits. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on parallel circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Four lessons are included in the…

  17. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Ten: Transformers. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on transformers is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Six lessons are included in the module:…

  18. Individual differences in the radiosensitivity of hematopoietic progenitor cells detected in steady-state human peripheral blood

    International Nuclear Information System (INIS)

    Oriya, Asami; Takahashi, Kenji; Kashiwakura, Ikuo; Inanami, Osamu; Kuwabara, Mikinori; Miura, Toshiaki; Abe, Yoshinao

    2008-01-01

    The aim of this study is to evaluate the individual differences in radiosensitivity of lineage-committed myeloid hematopoietic progenitors, colony-forming cells (CFC), detected in steady-state human peripheral blood (PB). Mononuclear cells were prepared from the buffy-coat of 30 individuals PB, and were assayed for CFC by semi-solid culture supplemented with cytokines. X irradiation was performed in the range of 0.5-4 Gy at a dose rate of about 80 cGy/min. The mean number of hematopoietic progenitor cells is 5866±3408 in 1 ml of buffy-coat, suggesting that the erythroid progenitor cells are the major population. The total CFC radiosensitivity parameter D 0 and n value are 1.18±0.24 and 1.89±0.98, respectively. Using a linear regression analysis, a statistically significant correlation is observed between the D 0 value and the surviving fraction at 4 Gy (r=0.611 p 0 parameter and the level of antioxidants, plasma uric acid, plasma bilirubin, and intracellular glutathione. The present study demonstrates that there are large individual differences in the radiosensitivity of hematopoietic progenitor cells as detected in steady-state human PB. These differences demonstrate almost no correlation with plasma or intracellular antioxidants. The prediction of individual differences in radiosensitivity of CFC can only be measured by 4 Gy irradiation. (author)

  19. Projectile- and charge-state-dependent electron yields from ion penetration of solids as a probe of preequilibrium stopping power

    DEFF Research Database (Denmark)

    Rothard, H.; Schou, Jørgen; Groeneveld, K.-O.

    1992-01-01

    Kinetic electron-emission yields gamma from swift ion penetration of solids are proportional to the (electronic) stopping power gamma approximately Beta-S*, if the preequilibrium evolution of the charge and excitation states of the positively charged ions is taken into account. We show...... by investigating the "transport factor" beta, the energy spectrum of directly ejected recoil electrons and the evolution of ionic charge state inside solids. Estimates of the energy-loss fraction leading to electron emission and the effective charges of the ions near the surface allow a quantitative description...

  20. Amygdala volume linked to individual differences in mental state inference in early childhood and adulthood

    Directory of Open Access Journals (Sweden)

    Katherine Rice

    2014-04-01

    Full Text Available We investigated the role of the amygdala in mental state inference in a sample of adults and in a sample of children aged 4 and 6 years. This period in early childhood represents a time when mentalizing abilities undergo dramatic changes. Both children and adults inferred mental states from pictures of others’ eyes, and children also inferred the mental states of others from stories (e.g., a false belief task. We also collected structural MRI data from these participants, to determine whether larger amygdala volumes (controlling for age and total gray matter volume were related to better face-based and story-based mentalizing. For children, larger amygdala volumes were related to better face-based, but not story-based, mentalizing. In contrast, in adults, amygdala volume was not related to face-based mentalizing. We next divided the face-based items into two subscales: cognitive (e.g., thinking, not believing versus affective (e.g., friendly, kind items. For children, performance on cognitive items was positively correlated with amygdala volume, but for adults, only performance on affective items was positively correlated with amygdala volume. These results indicate that the amygdala's role in mentalizing may be specific to face-based tasks and that the nature of its involvement may change over development.