WorldWideScience

Sample records for electronic transition energies

  1. Variation of kinetic energy release with temperature and electron energy for unimolecular ionic transitions

    International Nuclear Information System (INIS)

    Rabia, M.A.; Fahmy, M.A.

    1992-01-01

    The kinetic energy released during seven unimolecular ionic transitions, generated from benzyl alcohol and benzyl amine have been studied as a function of ion source temperature and ionizing electron energy. Only, the kinetic energy released during H CN elimination from fragment [C 7 H 8 N]+ ion of benzyl amine displays a temperature dependence. For only two transitions, generated from benzyl alcohol, the kinetic energy released show a significant ionizing electron energy dependence. These results may reveal the role of the internal energy of reacting ions in producing the kinetic energy released some transitions produced from benzyl alcohol

  2. Influence of host matrices on krypton electron binding energies and KLL Auger transition energies

    Czech Academy of Sciences Publication Activity Database

    Inoyatov, A. K.; Perevoshchikov, L. L.; Kovalík, Alojz; Filosofov, D. V.; Yushkevich, Yu. V.; Ryšavý, Miloš; Lee, B. Q.; Kibédi, T.; Stuchbery, A. E.; Zhdanov, V. S.

    2014-01-01

    Roč. 197, DEC (2014), s. 64-71 ISSN 0368-2048 R&D Projects: GA ČR(CZ) GAP203/12/1896; GA MŠk LG14004 Institutional support: RVO:61389005 Keywords : Kr-83 * Rb-83 * Sr-83 * electron binding energy * KLL transitions * natural atomic level width * multiconfiguration Dirac-Fock calculations Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.436, year: 2014

  3. Treatment of Electronic Energy Level Transition and Ionization Following the Particle-Based Chemistry Model

    Science.gov (United States)

    Liechty, Derek S.; Lewis, Mark

    2010-01-01

    A new method of treating electronic energy level transitions as well as linking ionization to electronic energy levels is proposed following the particle-based chemistry model of Bird. Although the use of electronic energy levels and ionization reactions in DSMC are not new ideas, the current method of selecting what level to transition to, how to reproduce transition rates, and the linking of the electronic energy levels to ionization are, to the author s knowledge, novel concepts. The resulting equilibrium temperatures are shown to remain constant, and the electronic energy level distributions are shown to reproduce the Boltzmann distribution. The electronic energy level transition rates and ionization rates due to electron impacts are shown to reproduce theoretical and measured rates. The rates due to heavy particle impacts, while not as favorable as the electron impact rates, compare favorably to values from the literature. Thus, these new extensions to the particle-based chemistry model of Bird provide an accurate method for predicting electronic energy level transition and ionization rates in gases.

  4. Determination of electron bunch shape using transition radiation and phase-energy measurements

    Energy Technology Data Exchange (ETDEWEB)

    Crosson, E.R.; Berryman, K.W.; Richman, B.A. [Stanford Univ., CA (United States)] [and others

    1995-12-31

    We present data comparing microbunch temporal information obtained from electron beam phase-energy measurements with that obtained from transition radiation auto-correlation measurements. The data was taken to resolve some of the ambiguities in previous transition radiation results. By measuring the energy spectrum of the electron beam as a function of its phase relative to the accelerating field, phase-energy information was extracted. This data was analyzed using tomographic techniques to reconstruct the phase-space distribution assuming an electron energy dependence of E({var_phi}) = E{sub o} + E{sub acc}cos({var_phi}), where E{sub o} is the energy of an electron entering the field, E{sub acc} is the peak energy gain, and {var_phi} is the phase between the crest of the RF wave and an electron. Temporal information about the beam was obtained from the phase space distribution by taking the one dimensional projection along the time axis. We discuss the use of this technique to verify other transition radiation analysis methods.

  5. Determination of electron bunch shape using transition radiation and phase-energy measurements

    International Nuclear Information System (INIS)

    Crosson, E.R.; Berryman, K.W.; Richman, B.A.

    1995-01-01

    We present data comparing microbunch temporal information obtained from electron beam phase-energy measurements with that obtained from transition radiation auto-correlation measurements. The data was taken to resolve some of the ambiguities in previous transition radiation results. By measuring the energy spectrum of the electron beam as a function of its phase relative to the accelerating field, phase-energy information was extracted. This data was analyzed using tomographic techniques to reconstruct the phase-space distribution assuming an electron energy dependence of E(var-phi) = E o + E acc cos(var-phi), where E o is the energy of an electron entering the field, E acc is the peak energy gain, and var-phi is the phase between the crest of the RF wave and an electron. Temporal information about the beam was obtained from the phase space distribution by taking the one dimensional projection along the time axis. We discuss the use of this technique to verify other transition radiation analysis methods

  6. Quantum Geometry: Relativistic energy approach to cooperative electron-nucleary-transition spectrum

    Directory of Open Access Journals (Sweden)

    Ольга Юрьевна Хецелиус

    2014-11-01

    Full Text Available An advanced relativistic energy approach is presented and applied to calculating parameters of electron-nuclear 7-transition spectra of nucleus in the atom. The intensities of the spectral satellites are defined in the relativistic version of the energy approach (S-matrix formalism, and gauge-invariant quantum-electrodynamical perturbation theory with the Dirac-Kohn-Sham density-functional zeroth approximation.

  7. First principles study of electronic properties, interband transitions and electron energy loss of α-graphyne

    Science.gov (United States)

    Behzad, Somayeh

    2016-04-01

    The electronic and optical properties of α-graphyne sheet are investigated by using density functional theory. The results confirm that α-graphyne sheet is a zero-gap semimetal. The optical properties of the α-graphyne sheet such as dielectric function, refraction index, electron energy loss function, reflectivity, absorption coefficient and extinction index are calculated for both parallel and perpendicular electric field polarizations. The optical spectra are strongly anisotropic along these two polarizations. For (E ∥ x), absorption edge is at 0 eV, while there is no absorption below 8 eV for (E ∥ z).

  8. Energy transition

    International Nuclear Information System (INIS)

    Anon.

    2013-01-01

    The yearly environmental conference will hold on September 2013 to evaluate the negotiations led at the national and local levels for december 2012. The government will have then to decide of an energy programming bill which will be submitted to the Parliament at the beginning of the year 2014. 30 main propositions have emerged of the decentralised debates. One of them is the ecological taxation which raise the question of the gas oil and petrol taxation. The current environmental taxes are for almost three quarters of them taxes on energy consumptions and mainly on fossil energies. The Economic, Social and Environmental Council, gives his opinion on the way to find resources to ensure the ecological and energy transition while reducing the public deficit of the State. (O.M.)

  9. Free-Free Transitions in the Presence of Laser Fields at Very Low Incident Electron Energy

    Science.gov (United States)

    Bhatia, A. K.; Sinha, Chandana

    2010-01-01

    We study the free-free transition in electron-hydrogenic systems in ground state in presence of an external laser field at very loud incident energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The laser field is chosen to be monochromatic, linearly polarized and homogeneous. The incident electron is considered to be dressed by the laser in a nonperturbative manner by choosing a Volkov wave function for it. The scattering weave function for the electron is solved numerically by taking into account the effect of the electron exchange, short-range as well as of the long-range interactions to get the S and P wave phase shifts while for the higher angular momentum phase shifts the exchange approximation has only been considered. We calculate the laser assisted differential cross sections (LADCS) for the aforesaid free-free transition process for single photon absorption/emission. The laser intensity is chosen to be much less than the atomic field intensity. A strong suppression is noted in the LADCS as compared to the field free (FF) cross sections. Unlike the FF ones, the LADCS exhibit some oscillations having a distinct maximum at a low value of the scattering angle depending on the laser parameters as well as on the incident energies.

  10. Free-Free Transitions in the Presence of Laser Fields and Debye Potential at Very Low Incident Electron Energies

    Science.gov (United States)

    Bhatia, Anand

    2012-01-01

    We study the free-free transition in electron-helium ion in the ground state and embedded in a Debye potential in the presence of an external laser field at very low incident electron energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The laser field is chosen as monochromatic, linearly polarized and homogeneous. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing Volkov wave function for it. The scattering wave function for the incident electron on the target embedded in a Debye potential is solved numerically by taking into account the effect of electron exchange. We calculate the laser-assisted differential and total cross sections for free-free transition for absorption/emission of a single photon or no photon exchange. The results will be presented at the conference.

  11. Study of electron transition energies between anions and cations in spinel ferrites using differential UV–vis absorption spectra

    International Nuclear Information System (INIS)

    Xue, L.C.; Wu, L.Q.; Li, S.Q.; Li, Z.Z.; Tang, G.D.; Qi, W.H.; Ge, X.S.; Ding, L.L.

    2016-01-01

    It is very important to determine electron transition energies (E_t_r) between anions and different cations in order to understand the electrical transport and magnetic properties of a material. Many authors have analyzed UV–vis absorption spectra using the curve (αhν)"2 vs E, where α is the absorption coefficient and E(=hν) is the photon energy. Such an approach can give only two band gap energies for spinel ferrites. In this paper, using differential UV–vis absorption spectra, dα/dE vs E, we have obtained electron transition energies (E_t_r) between the anions and cations, Fe"2"+ and Fe"3"+ at the (A) and [B] sites and Ni"2"+ at the [B] sites for the (A)[B]_2O_4 spinel ferrite samples Co_xNi_0_._7_−_xFe_2_._3O_4 (0.0≤x≤0.3), Cr_xNi_0_._7Fe_2_._3_−_xO_4 (0.0≤x≤0.3) and Fe_3O_4. We suggest that the differential UV–vis absorption spectra should be accepted as a general analysis method for determining electron transition energies between anions and cations.

  12. Transition to electronic publishing

    Science.gov (United States)

    Bowning, Sam

    Previous communications have described some of the many changes that will occur in the next few months as AGU makes the transition to fully electronic publishing. With the advent of the new AGU electronic publishing system, manuscripts will be submitted, edited, reviewed, and published in electronic formats. This piece discusses how the electronic journals will differ from the print journals. Electronic publishing will require some adjustments to the ways we currently think about journals from our perspective of standard print versions. Visiting the Web site of AGU's Geochemistry, Geophysics, Geosystems (G-Cubed) is a great way to get familiar with the look and feel of electronic publishing. However, protocols, especially for citations of articles, are still evolving. Some of the biggest changes for users of AGU publications may be the lack of page numbers, the use of a unique identifier (DOI),and changes in citation style.

  13. Studies of transfer reactions of photosensitized electrons involving complexes of transition metals in view of solar energy storage

    International Nuclear Information System (INIS)

    Takakubo, Masaaki

    1984-01-01

    This research thesis addresses electron transfer reactions occurring during photosynthesis, for example, photosensitized reaction in which chlorophyll is the sensitizer. More specifically, the author studied experimentally electron photo-transfers with type D sensitizers (riboflavin, phenoxazine and porphyrin), and various complexes of transition metals. After a presentation of these experiments, the author describes the photosensitisation process (photo-physics of riboflavin, oxygen deactivation, sensitized photo-oxidation and photo-reduction). The theoretical aspect of electron transfer is then addressed: generalities, deactivation of the riboflavin triplet, initial efficiency of electron transfer. Experimental results on three basic processes (non-radiative deactivation, energy transfer, electron transfer) are interpreted in a unified way by using the non-radiative transfer theory. Some applications are described: photo-electrochemical batteries, photo-oxidation and photo-reduction of the cobalt ion

  14. Changes in core electron temperature fluctuations across the ohmic energy confinement transition in Alcator C-Mod plasmas

    International Nuclear Information System (INIS)

    Sung, C.; White, A.E.; Howard, N.T.; Oi, C.Y.; Rice, J.E.; Gao, C.; Ennever, P.; Porkolab, M.; Parra, F.; Ernst, D.; Walk, J.; Hughes, J.W.; Irby, J.; Kasten, C.; Hubbard, A.E.; Greenwald, M.J.; Mikkelsen, D.

    2013-01-01

    The first measurements of long wavelength (k y ρ s < 0.3) electron temperature fluctuations in Alcator C-Mod made with a new correlation electron cyclotron emission diagnostic support a long-standing hypothesis regarding the confinement transition from linear ohmic confinement (LOC) to saturated ohmic confinement (SOC). Electron temperature fluctuations decrease significantly (∼40%) crossing from LOC to SOC, consistent with a change from trapped electron mode (TEM) turbulence domination to ion temperature gradient (ITG) turbulence as the density is increased. Linear stability analysis performed with the GYRO code (Candy and Waltz 2003 J. Comput. Phys. 186 545) shows that TEMs are dominant for long wavelength turbulence in the LOC regime and ITG modes are dominant in the SOC regime at the radial location (ρ ∼ 0.8) where the changes in electron temperature fluctuations are measured. In contrast, deeper in the core (ρ < 0.8), linear stability analysis indicates that ITG modes remain dominant across the LOC/SOC transition. This radial variation suggests that the robust global changes in confinement of energy and momentum occurring across the LOC/SOC transition are correlated to local changes in the dominant turbulent mode near the edge. (paper)

  15. Uncorrelated electron-hole transition energy in GaN|InGaN|GaN spherical QDQW nanoparticles

    International Nuclear Information System (INIS)

    Haddou El Ghazi; Anouar Jorio and Izeddine Zorkani

    2013-01-01

    The electron (hole) energy and uncorrelated 1S e - 1S h electron-hole transition in Core(GaN)|well(In x Ga 1-x N)|shell(GaN) spherical QDQW nanoparticles is investigated as a function of the inner and the outer radii. The calculations are performed within the framework of the effective-mass approximation and the finite parabolic potential confinement barrier in which two confined parameters are taking account. The Indium composition effect is also investigated. A critical value of the outer and the inner ratio is obtained which constitutes the turning point of two indium composition behaviors. (author)

  16. The Energy Transition Chronicles

    International Nuclear Information System (INIS)

    Cappelletti, Floriane; Vallar, Jean-Pierre; Wyssling, Julia

    2015-01-01

    Energy Cities provides local authorities with support for implementing their own energy transition process. The Proposals for the energy transition of cities and towns (www.energy-cities.eu/30proposals) are illustrated with around a hundred of inspirational examples from all over Europe. In this document composed of five case reports, Energy Cities goes further and tells the tale of energy transition success stories. Because it is important to show that energy transition is 'possible'. Why, how, with whom, for what results? We interviewed local players and decision-makers to find out more. Here are their stories

  17. Electronic phase transitions

    CERN Document Server

    Kopaev, YuV

    1992-01-01

    Electronic Phase Transitions deals with topics, which are presently at the forefront of scientific research in modern solid-state theory. Anderson localization, which has fundamental implications in many areas of solid-state physics as well as spin glasses, with its influence on quite different research activities such as neural networks, are two examples that are reviewed in this book. The ab initio statistical mechanics of structural phase transitions is another prime example, where the interplay and connection of two unrelated disciplines of solid-state theory - first principle ele

  18. An investigation of the reflection of low energy electrons from the surfaces of layered transition metal dichalcogenides

    International Nuclear Information System (INIS)

    Smith, A.E.; Mohamed, M.H.; Wohlenberg, T.; Johnson, E.; Chadderton, L.T.; Moeller, P.J.

    1980-01-01

    Experimental measurements, using the total current spectroscopy (TCS) technique, on the energy dependence of the reflection of low energy electrons from clean surfaces of layered transition metal dichalcogenides are reported for the molybdenum semiconductor compounds 2H-MoS 2 and 2H-MoSe 2 . A simple model calculation involving both elastic and inelastic scattering is presented and correspondence established with the experimental spectra. In this picture information on the electronic band structure of the materials can then be extracted from the single particle component of the inelastic scattering. The model is extended to show that a feature in the 2H-MoS 2 experimental spectrum may be attributed to the excitation of an intermediate plasmon. (Auth.)

  19. The energy transition

    International Nuclear Information System (INIS)

    Passalacqua, Arnaud; Billes-Garabedian, Laurent; Jancovici, Jean-Marc; Arnoux, Mathieu; Auverlot, Dominique; Leguet, Benoit; Grandjean, Alain; Morel, Julien; Lambert, Quentin; Tranie, Jean-Pascal; Bureau, Dominique; Dron, Dominique; Beeker, Etienne

    2013-01-01

    This special dossier about energy transition is made of 10 contributions dealing with: thousands of years of energy transition (Jean-Marc Jancovici); a recurring problem after a thousand years of fight (Mathieu Arnoux); urban mobility: another energy story (Arnaud Passalacqua); an opportunity subjected to conditions for the French competitiveness (Dominique Auverlot, Benoit Leguet); Germany: an energy utopia or a role model? (Etienne Beeker); environment: the financing stakes (Dominique Dron); reconciling the economical, social and ecological stakes (Alain Grandjean); Sweden in the face of transportation challenge (Julien Morel, Quentin Lambert); India and China with a commitment to global warming (Jean-Pascal Tranie); training the energy transition managers (Dominique Bureau)

  20. A benchmark study of electronic excitation energies, transition moments, and excited-state energy gradients on the nicotine molecule

    Energy Technology Data Exchange (ETDEWEB)

    Egidi, Franco, E-mail: franco.egidi@sns.it; Segado, Mireia; Barone, Vincenzo, E-mail: vincenzo.barone@sns.it [Scuola Normale Superiore, Piazza dei Cavalieri, 7 I-56126 Pisa (Italy); Koch, Henrik [Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim (Norway); Cappelli, Chiara [Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via G. Moruzzi, 3 I-56124 Pisa (Italy)

    2014-12-14

    In this work, we report a comparative study of computed excitation energies, oscillator strengths, and excited-state energy gradients of (S)-nicotine, chosen as a test case, using multireference methods, coupled cluster singles and doubles, and methods based on time-dependent density functional theory. This system was chosen because its apparent simplicity hides a complex electronic structure, as several different types of valence excitations are possible, including n-π{sup *}, π-π{sup *}, and charge-transfer states, and in order to simulate its spectrum it is necessary to describe all of them consistently well by the chosen method.

  1. Identification of very low energy projectile autoionizing transitions in high velocity collisions using zero-degree Auger electron spectroscopy

    International Nuclear Information System (INIS)

    Zouros, T.J.M.; Liao, C.; Montenegro, E.C.; Hagmann, S.; Richard, P.; Grabbe, S.; Bhalla, C.P.; Wong, K.L.

    1995-01-01

    The unusual looking ''mesa''-shaped cusp observed in O 3+ collisions with He [N. Stolterfoht et al., Proc. 2nd US-Mexico Symp. on Atomic and Molecular Phy. eds. A. Cisneros and T. Morgan (Instituto de Fysica, Cuernavaca, Mexico, 1986) p. 51.], has been investigated using zero-degree electron spectroscopy, in both high resolution singles measurements and lower resolution electron-projectile coincidence measurements at 10, 15 and 23 MeV. The high resolution studies indicate the ''mesa'' peak to be actually composed of primarily two (other than the cusp) very strong autoionizing peaks corresponding to energies of 60 and 100 meV in the emitter frame. The coincidence studies, indicate these lines to originate from excitation of the O 3+ ion followed by autoionization. Ongoing Hartree-Fock-Slater calculations, severely tested at these extremely small transition energies, indicate that these lines can indeed result from the autoionization of t he O 3+ (1s 2 2s2p5l) Rydberg states produced during the collision. Furthermore, the unusually sharp edges of these lines giving rise to the characteristic ''mesa''-shape look, can be explained in terms of the kinematic constraints imposed by the energy and angular acceptance range of the spectrometer. (orig.)

  2. Low-lying electronic states of the OH radical: potential energy curves, dipole moment functions, and transition probabilities

    Energy Technology Data Exchange (ETDEWEB)

    Qin, X.; Zhang, S. D. [Qufu Normal University, Qufu (China)

    2014-12-15

    The six doublet and the two quartet electronic states ({sup 2}Σ{sup +}(2), {sup 2}Σ{sup -}, {sup 2}Π(2), {sup 2}Δ, {sup 4}Σ{sup -}, and {sup 4}Π) of the OH radical have been studied using the multi-reference configuration interaction (MRCI) method where the Davidson correction, core-valence interaction and relativistic effect are considered with large basis sets of aug-cc-pv5z, aug-cc-pcv5z, and cc-pv5z-DK, respectively. Potential energy curves (PECs) and dipole moment functions are also calculated for these states for internuclear distances ranging from 0.05 nm to 0.80 nm. All possible vibrational levels and rotational constants for the bound state X{sup 2}Π and A{sup 2}Σ{sup +} of OH are predicted by numerical solving the radial Schroedinger equation through the Level program, and spectroscopic parameters, which are in good agreements with experimental results, are obtained. Transition dipole moments between the ground state X{sup 2}Π and other excited states are also computed using MRCI, and the transition probability, lifetime, and Franck-Condon factors for the A{sup 2}Σ{sup +} - X{sup 2}Π transition are discussed and compared with existing experimental values.

  3. Energy transition. Selective bibliography

    International Nuclear Information System (INIS)

    2015-10-01

    At the occasion of the promulgation on August 17, 2015 of law no. 2015-992 relative to energy transition, this bibliography reviews the legal, economical and political aspects of the recent evolutions in the energy domain. Basic and synthetic documents are listed first. Then follow documents dealing with: general data, energy models, sustainable agriculture, green technologies, energy conservation, waste processing, renewable energy sources, sustainable cities and buildings. The bibliography ends with a selection of relevant web sites

  4. Electronic Transitions of Tungsten Monosulfide

    Science.gov (United States)

    Tsang, L. F.; Chan, Man-Chor; Zou, Wenli; Cheung, Allan S. C.

    2017-06-01

    Electronic transition spectrum of the tungsten monosulfide (WS) molecule in the near infrared region between 725 nm and 885 nm has been recorded using laser ablation/reaction free-jet expansion and laser induced fluorescence spectroscopy. The WS molecule was produced by reacting laser - ablated tungsten atoms with 1% CS_{2} seeded in argon. Fifteen vibrational bands with resolved rotational structure have been recorded and analyzed, which were organized into seven electronic transition systems. The ground state has been identified to be the X^{3}Σ^{-}(0^{+}) state, and the determined vibrational frequency, ΔG_{1/2} and bond length, r_{0}, are respectively 556.7 cm^{-1} and 2.0676 Å. In addition, vibrational bands belong to another transition system involving lower state with Ω = 1 component have also been analyzed. Least-squares fit of the measured line positions yielded molecular constants for the electronic states involved. The low-lying Λ-S states and Ω sub-states of WS have been calculated using state-averaged complete active space self-consistent field (SA-CASSCF) and followed by MRCISD+Q (internally contracted multi-reference configuration interaction with singles and doubles plus Davidson's cluster correction). The active space consists of 10 electrons in 9 orbitals corresponding to the W 5d6s and S 3p shells. The lower molecular orbitals from W 5s5p and S 3s are inactive but are also correlated, and relativistic effective core potential (RECPs) are adopted to replace the core orbitals with 60 (W) and 10 (S) core electrons, respectively. Spin-orbit coupling (SOC) is calculated via the state-interaction (SI) approach with RECP spin-orbit operators using SA-CASSCF wavefunctions, where the diagonal elements in the SOC matrix are replaced by the corresponding MRCISD+Q energies calculated above. Spectroscopic constants and potential energy curves of the ground and many low-lying Λ-S states and Ω sub-states of the WS molecule are obtained. The calculated

  5. Transition densities with electron scattering

    International Nuclear Information System (INIS)

    Heisenberg, J.

    1985-01-01

    This paper reviews the ground state and transition charge densities in nuclei via electron scattering. Using electrons as a spectroscopic tool in nuclear physics, these transition densities can be determined with high precision, also in the nuclear interior. These densities generally ask for a microscopic interpretation in terms of contributions from individual nucleons. The results for single particle transitions confirm the picture of particle-phonon coupling. (Auth.)

  6. Measurement of Auger electron energies and intensities from muonic transitions in silver

    International Nuclear Information System (INIS)

    Callies, R.; Daniel, H.; Egidy, T. von; Hagn, H.; Hartmann, F.J.; Neumann, W.

    1983-01-01

    There is now general agreement that Coulomb capture of mesonic particles and deexcitation of the formed exotic atom must be accompanied by Auger electron emission. Auger electrons from a thin silver foil were counted by Si-pn-junction detectors with an extraordinarily thin dead layer. Lines could be resolved and intensity ratios determined. Two types of experiments were performed simultaneously, (I) with the slow-muon telescope in coincidence with any e - detector of the array and (II) as above but with an additional Ag X-ray coincidence from a Ge(Li) detector placed close to the target. (Auth.)

  7. Variational predictions of transition energies and electron affinities: He and Li ground states and Li, Be, and Mg core-excited states

    International Nuclear Information System (INIS)

    Fischer, C.F.

    1990-01-01

    Variational procedures for predicting energy differences of many-electron systems are investigated. Several different calculations for few-electron systems are considered that illustrate the problems encountered when a many-electron system is modeled as a core plus outer electrons. It is shown that sequences of increasingly more accurate calculations for outer correlation may converge yielding wrong transition energies. At the same time, accurate core-polarization calculations overestimate the binding energy, requiring a core-valence correction. For the high-spin, core-excited states of Li, it was found that outer correlation only predicted electron affinities as accurately as full-correlation studies. This observation suggested a prediction of the core-excited 4 P endash 4 S transition in Be - , based on observed 3 P 0 endash 3 P transition energies of the neutral species, predicted electron affinities including only outer correlation, and a core-valence correction, that is shown to be in good agreement with experiment. A similar calculation for Mg - predicts a wavelength of 2895.1 A for this transition

  8. The energy transition

    International Nuclear Information System (INIS)

    Defeuilley, Christophe

    2014-01-01

    In a first part, the author proposes an analysis of energy transition and of its consequences on the competitive environment. He recalls the main characteristics of energy transition and more particularly focuses on two aspects: the development of renewable energies and the management of demand. Thus, the author discusses the following issues: the relationship between the struggle against climate change and the low carbon economy, the development of renewable energies, the evolution and main actors of photovoltaic array and of wind turbine production, the distribution of photovoltaic and wind energy installed production among countries, and some key figures about the main renewable energy operators in Europe. He discusses how to manage consumptions, and operations performed. In a second part, the author addresses the impact of the German energy transition (Energiewende) on the business models of the main German energy operators (RWE and E.On). He recalls and comments the objective of this energy policy, presents the German electric and gas sector, comments the evolution of the electric utilities since 1998, more presently presents and discusses the activities of RWE and E.On, the evolution of their main financial indicators, and the levels of installed power with respect of energy sources

  9. Energy transition in France

    International Nuclear Information System (INIS)

    Grandjean, Alain

    2014-01-01

    After having recalled the main issues and stakes addressed by the French national debate on energy transition (strategic stakes, priority to a reduction of French energy consumption, options for the evolution of the French energy mix), the author comments the possible evolution of energy prices and of the energy taxing policy (evolution of oil prices, carbon price). In a second part, the author addresses the issue of financing of building and housing renovation. He shows that this operation cannot be only based on financial markets which are not efficient. This means that a public intervention is required, and different solutions are then possible. Some of them seem difficult to implement (creation of money by the central Bank, creation of a public bank which could lend money to private actors), and some others need to be further examined (creation of a financing company for energy transition, use of national savings, simplified circuits for a financing of local projects by local savings, and so on)

  10. MgH Rydberg series: Transition energies from electron propagator theory and oscillator strengths from the molecular quantum defect orbital method

    Science.gov (United States)

    Corzo, H. H.; Velasco, A. M.; Lavín, C.; Ortiz, J. V.

    2018-02-01

    Vertical excitation energies belonging to several Rydberg series of MgH have been inferred from 3+ electron-propagator calculations of the electron affinities of MgH+ and are in close agreement with experiment. Many electronically excited states with n > 3 are reported for the first time and new insight is given on the assignment of several Rydberg series. Valence and Rydberg excited states of MgH are distinguished respectively by high and low pole strengths corresponding to Dyson orbitals of electron attachment to the cation. By applying the Molecular Quantum Defect Orbital method, oscillator strengths for electronic transitions involving Rydberg states also have been determined.

  11. Energy systems in transition

    International Nuclear Information System (INIS)

    Haefele, W.

    1989-01-01

    The principal point of the author was to discuss energy systems (ES) in transition, transition addresses the next 10-25 years, and strategy of the transition. He considers different scenarios of future development of ES. Further he presents considerations elaborated during the last years on the concept of novel horizontally integrated ES which gives promise to be at least an approximation to the desired object of no emissions. The main ideas of the concept are: to decompose and thereby clean all the primary inputs before they are brought to combustion; to develop a network combining all the primary inputs to an integrated supply structure of high absorption, buffer, and storage capacity that resembles in some way the supply and utility functions of the well established electric grid but completes it at best on the basis of mass flows; to achieve a high flexibility in supplying the final energy. The author considers the long run perspective of hydrogen, solar, and nuclear energy with respect to alternative energy sources. 6 refs, 24 figs

  12. Energy transition in action

    International Nuclear Information System (INIS)

    2014-07-01

    By presenting examples and experiments implemented in France, this publication illustrates the various ways to translate the objectives of energy transition into practical actions. A first part addresses the building sector and shows how to better renovate buildings: exemplary rehabilitations, techniques of construction to decrease energy consumption and equipment to control it, insulation by vegetal fibres, control of consumption decrease. The second part addresses the development of renewable energies: a heat network for household heating, innovative use of biogas, production of hot water by using solar energy, a waste incineration plant, heating by using waste waters. The third part addresses the promotion of circular economy: a recycling project, an optics-based glass sorting system, the commitment of Parisian restaurateurs for waste valorisation, a plant for waste sorting and valorisation

  13. Calculation of nuclear excitation in an electron transition

    Energy Technology Data Exchange (ETDEWEB)

    Pisk, K. (Institut Rudjer Boskovic, Zagreb (Yugoslavia)); Kaliman, Z. (Rijeka Univ. (Yugoslavia). Faculty of Pedagogics); Logan, B.A. (Ottawa Univ., ON (Canada). Ottawa-Carleton Centre for Physics)

    1989-11-06

    We have made a theoretical investigation of nuclear excitation during an electron transition (NEET). Our approach allows us to express the NEET probabilities in terms of the excited nuclear level width, the energy difference between the nuclear and electron transition, the Coulomb interaction between the initial electron states, and the electron level width. A comparison is made with the available experimental results. (orig.).

  14. Energy: Transitions and Reshaping

    International Nuclear Information System (INIS)

    Hache, Emmanuel; Mazzucchi, Nicolas; Alex, Bastien; Tchung-Ming, Stephane; Meritet, Sophie; Mignon, Valerie; Fischer-Herzog, Claude; Baccarini, Luca; Karbuz, Sohbet; Carcanague, Samuel; Noreng, Oesteyn; Luciani, Giacomo; Criqui, Patrick

    2016-01-01

    This issue of 'Revue internationale et strategique' from Winter 2016 presents a special dossier about the geopolitics of energy in a transitional and reshaping market. Content: Introduction: A New Age for Energy Markets? (Emmanuel Hache); National vs International Oil Companies: Toward a New Balance (Nicolas Mazzucchi); Can OPEC Survive Oil Abundance? (Emmanuel Hache); Dutch Disease and Low Oil Prices: From Economic Bankruptcy to (geo)political Reshaping (Bastien Alex, Stephane Tchung-Ming); Is Energy a Driving Force in American Foreign Policy? (Sophie Meritet); Oil Prices and U.S. Dollar: Two Sides of the Same Power? (Valerie Mignon ); The EU's Energy Union: What Energy Security for Europe? (Claude Fischer-Herzog); Natural Gas Discoveries and the Future of the Eastern Mediterranean Region (Luca Baccarini, Sohbet Karbuz); The Two Years that Changed the Caspian Sea region (Samuel Carcanague); On Oil and Islam (Oeystein Noreng); Middle East: clean energy sources and the diversification of the oil economies? (Giacomo Luciani); After the Paris Agreement, the New Geopolitics of Energy Innovations (Patrick Criqui)

  15. Electronic transitions of fluorene, dibenzofuran, carbazole, and dibenzothiophene

    DEFF Research Database (Denmark)

    Nguyen, Duy Duc; Trunk, John; Nakhimovsky, Lina

    2010-01-01

    A comparative study of the electronic transitions of fluorene and its hetero-analogues dibenzofuran, carbazole, and dibenzothiophene was performed in a wide energy range. Gas phase, crystal phase, and linear dichroism electronic transmittance spectra were measured with synchrotron radiation...

  16. Energy transition and legal transition: renewable energies development in France

    International Nuclear Information System (INIS)

    Darson, Alice

    2015-01-01

    The way to an energy transition will be reached with an integration of renewable energies in our energy mix. This development includes a legal transition because the current legal context that applies to green energies is not efficient and does not contribute to this emergency. Changing the legal frame becomes a necessity and particularly the way these energies are governed, planned and supported. It's also important that administrative procedures that regulate the implantation of energies production system are set. At last, this legal transition will have to conciliate imperatives linked to the development of renewable energies with those governing the protection of surroundings, all aiming to a sustainable development. (author) [fr

  17. Surface structure determinations of crystalline ionic thin films grown on transition metal single crystal surfaces by low energy electron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Joel Glenn [Univ. of California, Berkeley, CA (United States)

    2000-05-01

    The surface structures of NaCl(100), LiF(100) and alpha-MgCl2(0001) adsorbed on various metal single crystals have been determined by low energy electron diffraction (LEED). Thin films of these salts were grown on metal substrates by exposing the heated metal surface to a molecular flux of salt emitted from a Knudsen cell. This method of investigating thin films of insulators (ionic salts) on a conducting substrate (metal) circumvents surface charging problems that plagued bulk studies, thereby allowing the use of electron-based techniques to characterize the surface.

  18. Energy levels, radiative rates and electron impact excitation rates for transitions in He-like Ga XXX, Ge XXXI, As XXXII, Se XXXIII and Br XXXIV

    International Nuclear Information System (INIS)

    Aggarwal, Kanti M; Keenan, Francis P

    2013-01-01

    We report calculations of energy levels, radiative rates and electron impact excitation cross sections and rates for transitions in He-like Ga XXX, Ge XXXI, As XXXII, Se XXXIII and Br XXXIV. The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates. For determining the collision strengths, and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) is used. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 49 levels of each ion. Additionally, theoretical lifetimes are provided for all 49 levels of the above five ions. Collision strengths are averaged over a Maxwellian velocity distribution and the effective collision strengths obtained listed over a wide temperature range up to 10 8 K. Comparisons are made with similar data obtained using the flexible atomic code (fac) to highlight the importance of resonances, included in calculations with darc, in the determination of effective collision strengths. Discrepancies between the collision strengths from darc and fac, particularly for some forbidden transitions, are also discussed. Finally, discrepancies between the present results for effective collision strengths with the darc code and earlier semi-relativistic R-matrix data are noted over a wide range of electron temperatures for many transitions in all ions. (paper)

  19. Energy levels, radiative rates and electron impact excitation rates for transitions in He-like Ga XXX, Ge XXXI, As XXXII, Se XXXIII and Br XXXIV

    Science.gov (United States)

    Aggarwal, Kanti M.; Keenan, Francis P.

    2013-04-01

    We report calculations of energy levels, radiative rates and electron impact excitation cross sections and rates for transitions in He-like Ga XXX, Ge XXXI, As XXXII, Se XXXIII and Br XXXIV. The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates. For determining the collision strengths, and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) is used. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest 49 levels of each ion. Additionally, theoretical lifetimes are provided for all 49 levels of the above five ions. Collision strengths are averaged over a Maxwellian velocity distribution and the effective collision strengths obtained listed over a wide temperature range up to 108 K. Comparisons are made with similar data obtained using the flexible atomic code (fac) to highlight the importance of resonances, included in calculations with darc, in the determination of effective collision strengths. Discrepancies between the collision strengths from darc and fac, particularly for some forbidden transitions, are also discussed. Finally, discrepancies between the present results for effective collision strengths with the darc code and earlier semi-relativistic R-matrix data are noted over a wide range of electron temperatures for many transitions in all ions.

  20. Electronic transitions and intermolecular forces

    International Nuclear Information System (INIS)

    Hemert, M.C. van.

    1981-01-01

    This thesis describes two different subjects - electronic transitions and intermolecular forces - that are related mainly by the following observation: The wavenumber at which an electronic transition in an atom or molecule occurs, depends on the environment of that atom or molecule. This implies, for instance, that when a molecule becomes solvated its absorption spectrum may be shifted either to the blue or to the red side of the original gasphase spectrum. In part I attention is paid to the experimental aspects of VUV spectroscopy, both in the gasphase and in the condensed phase. In part II a series of papers are presented, dealing with the calculation of intermolecular forces (and some related topics) both for the ground state and for the excited state interactions, using different non-empirical methods. The calculations provide, among other results, a semiquantitative interpretation of the spectral blue shifts encountered in our experiments. (Auth.)

  1. Energy transition, is it now?

    International Nuclear Information System (INIS)

    Combe, Matthieu; Thouverez, Pierre

    2016-06-01

    As French energy policy is now defined for energy transition, the contributions of this publication discuss implemented measures, what new laws will change, and what will be the consequences for industry. A first set of articles thus comments evolutions related to the implementation of energy transition in the building sector, how energy transition wants to get rid of wastage, how energy transition will impact the transport sector (public transports, car-pool and car sharing, bicycle, retail sector, airfields), and outline that President Hollande has fulfilled (nearly) all his commitments. The next article comments changes and critics made by the French constitutional Council on the law for energy transition. The next set of articles comments the results of an ADEME's study on bicycle kilometre allowance, discusses the issue of energy safety, and comments statements made by candidates to the French President election of 2012 on nuclear energy after the Fukushima accident

  2. Philosophical explorations on energy transition

    NARCIS (Netherlands)

    Geerts, Robert-Jan

    2017-01-01

    This dissertation explores energy transition from a philosophical perspective. It puts forward the thesis that energy production and consumption are so intimately intertwined with society that the transition towards a sustainable alternative will involve more than simply implementing novel

  3. Morocco: an unbiased energy transition

    International Nuclear Information System (INIS)

    Lavergne, Richard

    2015-01-01

    In October 2014, the International Energy Agency presented its first in depth report 'Morocco 2014 Energy Policy Review' of Morocco's energy policy, an evaluation and recommendations, with as reference the shared goals of the Agency. The accent was placed on renewable energies energy efficiency and climate change. The 'Moroccan way' of energy transition merits the attention of energy economists and of the negotiators involved in COP21. (authors)

  4. Free-Free Transitions of the e-H System Inside a Dense Plasma Irradiated by a Laser Field at Very Low Incident-Electron Energies

    Science.gov (United States)

    Bhatia, A. K.; Sinha, C.

    2012-01-01

    The free-free transition is studied for an electron-hydrogen atom in ground state when a low-energy electron (external) is injected into hydrogenic plasma in the presence of an external homogenous, monochromatic, and linearly polarized laser field. The effect of plasma screening is considered in the Debye-Huckel approximation. The calculations are performed in the soft photon limit. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing the Volkov solutions in both the initial and final channels. The space part of the scattering wave function for the electron is solved numerically by taking into account the electron exchange. The laser-assisted differential and total cross sections are calculated for single-photon absorption or emission and no-photon exchange in the soft photon limit, the laser intensity being much less than the atomic field intensity. The calculations have been carried out for various values of Debye parameter, ranging from 0.005 to 0.12. A strong suppression is noted in the laser-assisted cross sections as compared to the field-free situation. A significant difference is noted for the singlet and triplet cross sections. The suppression is much more in the triplet states.

  5. For a citizen energy transition

    International Nuclear Information System (INIS)

    Geze, Patrick; Bernon, Francoise; Alphandery, Claude; Albizzati, Amandine; Ballandras, Marc; Berland, Olivier; Peullemeulle, Justine; Causse, Laurent; Olivier, Dominique; Damerval, Francois; Lepage, Corinne; Dughera, Jacques; Bouchart, Christiane; Duracka, Nicolas; Ferrari, Albert; Noe, Julien; Soulias, Emmanuel; Gaspard, Albane; Greenwood, Marianne; Guy, Lionel; Kretzschmar, Cyril; Lalu, Delphine; Naett, Caroline; Raguet, Alex; Rouchon, Jean-Philippe; Ruedinger, Andreas; Sautter, Christian; Tudor, Ivan; Vaquie, Pierre-Francois; Vernier, Christophe; Youinou, Jean-Michel; Verny, Emmanuel; Claustre, Raphael; Leclercq, Michel

    2015-09-01

    This publication by a think tank specialised in social and solidarity economy first outlines that energy transition means a transition from the present energy model to a new model based on three pillars: a drastic reduction of energy consumption through sobriety (energy saving, struggle against wastage), an improvement of energy efficiency, and an energy mix based on renewable and sustainable resources. A first part proposes a discussion of what 'citizen' energy transition can be: general framework of energy transition, pioneering examples in Europe, citizen empowerment, importance of a decentralised model which is anchored in territories, general interest as a priority. Each of these issues and aspects is illustrated by examples. Then, as this evolution towards a citizen-based model requires a change of scale, the authors discuss how to involve public authorities and to adapt regulation, how to develop financing tools, how to support the emergence and development of projects, and how to be part of international dynamics. The author then discuss what their think tank can do to accelerate energy transition. Proposals made in the different chapters are then summarized

  6. Macroeconomic models and energy transition

    International Nuclear Information System (INIS)

    Douillard, Pierre; Le Hir, Boris; Epaulard, Anne

    2016-02-01

    As a new policy for energy transition has just been adopted, several questions emerge about the best way to reduce CO 2 emissions, about policies which enable this reduction, and about their costs and opportunities. This note discusses the contribution macro-economic models may have in this respect, notably in the definition of policies which trigger behaviour changes, and those which support energy transition. The authors first discuss the stakes of the assessment of energy transition, and then describe macro-economic models which can be used for such an assessment, give and comment some results of simulations performed for France by using four of these models (Mesange, Numesis, ThreeME, and Imaclim-R France). The authors finally draw lessons about the way to use these models and to interpret their results within the frame of energy transition

  7. Hydrogen in energy transition

    International Nuclear Information System (INIS)

    2016-02-01

    This publication proposes a rather brief overview of challenges related to the use of hydrogen as an energy vector in the fields of transports and of energy storage to valorise renewable energies. Processes (steam reforming of natural gas or bio-gas, alkaline or membrane electrolysis, biological production), installation types (centralised or decentralised), raw materials and/or energy (natural gas, water, bio-gas, electricity, light), and their respective industrial maturity are indicated. The role of hydrogen to de-carbonate different types of transports is described (complementary energy for internal combustion as well as electrical vehicles) as well as its role in the valorisation and integration of renewable energies. The main challenges faced by the hydrogen sector are identified and discussed, and actions undertaken by the ADEME are indicated

  8. Energy innovation and transition

    DEFF Research Database (Denmark)

    Rønne, Anita

    Given pressing climate challenges such as global warming, air pollution, and pressure on natural resources, greening energy is at the very forefront of the political agenda. The energy sector and its regulation in the European Union, its member states, and indeed in the world in general...... of climate change. What are the goals and what changes are necessary in the future supply and consumption of fuels and energy if it is to live up to the mantra of becoming ‘smart’? Focus will address the shift towards a more intelligent and sustainable society improving the way people may live in cities...

  9. Auroral electron energies

    International Nuclear Information System (INIS)

    McEwan, D.J.; Duncan, C.N.; Montalbetti, R.

    1981-01-01

    Auroral electron characteristic energies determined from ground-based photometer measurements of the ratio of 5577 A OI and 4278 A N 2 + emissions are compared with electron energies measured during two rocket flights into pulsating aurora. Electron spectra with Maxwellian energy distributions were observed in both flights with an increase in characteristic energy during each pulsation. During the first flight on February 15, 1980 values of E 0 ranging from 1.4 keV at pulsation minima to 1.8 keV at pulsation maxima were inferred from the 5577/4278 ratios, in good agreement with rocket measurements. During the second flight on February 23, direct electron energy measurements yielded E 0 values of 1.8 keV rising to 2.1 keV at pulsation maxima. The photometric ratio measurements in this case gave inferred E 0 values about 0.5 keV lower. This apparent discrepancy is considered due to cloud cover which impaired the absolute emission intensity measurements. It is concluded that the 5577/4278 ratio does yield a meaningful measure of the characteristic energy of incoming electrons. This ratio technique, when added to the more sensitive 6300/4278 ratio technique usable in stable auroras can now provide more complete monitoring of electron influx characteristics. (auth)

  10. Energy in transition

    International Nuclear Information System (INIS)

    Williams, L.O.

    1986-01-01

    A plentiful, benign supply of energy is essential for a high standard of living. The current temporary oil surplus will soon be exhausted. Because of air pollution and the possible climatic changes which may be caused by increasing carbon dioxide in the atmosphere, fossil fuel combustion should be reduced. Oil and coal extraction also damage the environment. Fission nuclear energy has problems, fusion research lacks research funds. Renewable energy systems have not shown much promise for large-scale use. New energy systems must be developed and implemented. A system with fusion as the primary source and hydrogen (from the electrolysis of water) as the storage and distribution medium, is suggested as a potential system. (U.K.)

  11. Another transition in energy

    International Nuclear Information System (INIS)

    Beltran, A.

    2006-01-01

    Turmoil in macro-energy is occurring along with institutional changes that the French do not always unanimously follow. Habituated to the French public service model, which has maintained a fair level of prices and a constant supply of energy insofar as possible, the French are discovering a complex system that hinges ever more on services rather than prices: the culture of competition, complementarity and service. We must learn to sell and not just produce, to accept newcomers and become flexible. (author)

  12. Free-Free Transitions of e-H System Inside a Dense Plasma Irradiated by a Laser Field at Very Low Incident Electron Energies

    Science.gov (United States)

    Bhatia, A. K.; Sinha, C.

    2012-01-01

    The free-free transition is studied for an electron-hydrogen in the ground state at low incident energies in the presence of an external homogenous, monochromatic, and linearly polarized laser-field inside a hot dense plasma.The effect of plasma screening is considered in the Debye-Huckel approximation. The calculations are performed in the soft photon limit, assuming that the plasma frequency is much higher than the laser frequency. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing the Volkov solutions in both the initial and final channels. The space part of the scattering wave function for the electron is solved numerically by taking into account the electron exchange. The laser-assisted differential and total cross sections are calculated for single-photon absorption /emission and no photon exchange in the soft photon limit, the laser intensity being much less than the atomic field intensity. The calculations have been carried out for various values of Debye parameter, ranging from 0.005 to 0.12. A strong suppression is noted in the laser-assisted cross sections as compared to the field-free situation. A significant difference is noted for the singlet and triplet cross sections. The suppression is much more in the triplet states.

  13. Energy efficiency: Lever for the Energy Transition

    International Nuclear Information System (INIS)

    2012-12-01

    The Eco-electric industry group (FFIE, FGME, Gimelec, IGNES, SERCE) has conducted a study to evaluate the energy saving potential of active energy efficiency solutions in the residential and commercial building sectors. Based on field implementations and demonstrators, it has been demonstrated that active energy efficiency can sustainably achieve substantial savings for households, companies and public authorities. Energy Efficiency - Lever for the energy transition presents the results and conclusions of that study, alongside with recommendations for public authority in terms of building retrofit policy for putting France on the best possible 'trajectory' from a budgetary and environmental point of view. (author)

  14. Hydrogen: energy transition under way

    International Nuclear Information System (INIS)

    Franc, Pierre-Etienne; Mateo, Pascal

    2015-01-01

    Written by a representative of Air Liquide with the help of a free lance journalist, this book proposes an overview of the technological developments for the use of hydrogen as a clean energy with its ability to store primary energy (notably that produced by renewable sources), and its capacity of energy restitution in combination with a fuel cell with many different applications (notably mobility-related applications). The authors outline that these developments are very important in a context of energy transition. They also outline what is left to be done, notably economically and financially, for hydrogen to play its role in the energy revolution which is now under way

  15. Electron energies in metals

    International Nuclear Information System (INIS)

    Mahan, G.D.; Tennessee Univ., Knoxville, TN

    1991-01-01

    The modern era of electron-electron interactions began a decade ago. Plummer's group initiated a program of using angular resolved photoemission to examine the band structure of the simple metals. Beginning with aluminum, and carrying on to sodium and potassium, they always found that the occupied energy bands were much narrower than expected. For example, the compressed energy bands for metallic potassium suggest a band effective mass of m* = 1.33m e . This should be compared to the band mass found from optical conductivity m*/m e = 1.01 ± 0.01. The discrepancy between these results is startling. It was this great difference which started my group doing calculations. Our program was two-fold. On one hand, we reanalyzed the experimental data, in order to see if Plummer's result was an experimental artifact. On the other hand, we completely redid the electron-electron self-energy calculations for simple metals, using the most modern choices of local-field corrections and vertex corrections. Our results will be reported in these lectures. They can be summarized as following: Our calculations give the same effective masses as the older calculations, so the theory is relatively unchanged; Our analysis of the experiments suggests that the recent measurements of band narrowing are an experimental artifact. 38 refs., 9 figs

  16. Anomalous High-Energy Waterfall-Like Electronic Structure in 5 d Transition Metal Oxide Sr2IrO4 with a Strong Spin-Orbit Coupling

    Science.gov (United States)

    Liu, Yan; Yu, Li; Jia, Xiaowen; Zhao, Jianzhou; Weng, Hongming; Peng, Yingying; Chen, Chaoyu; Xie, Zhuojin; Mou, Daixiang; He, Junfeng; Liu, Xu; Feng, Ya; Yi, Hemian; Zhao, Lin; Liu, Guodong; He, Shaolong; Dong, Xiaoli; Zhang, Jun; Xu, Zuyan; Chen, Chuangtian; Cao, Gang; Dai, Xi; Fang, Zhong; Zhou, X. J.

    2015-08-01

    The low energy electronic structure of Sr2IrO4 has been well studied and understood in terms of an effective Jeff = 1/2 Mott insulator model. However, little work has been done in studying its high energy electronic behaviors. Here we report a new observation of the anomalous high energy electronic structure in Sr2IrO4. By taking high-resolution angle-resolved photoemission measurements on Sr2IrO4 over a wide energy range, we have revealed for the first time that the high energy electronic structures show unusual nearly-vertical bands that extend over a large energy range. Such anomalous high energy behaviors resemble the high energy waterfall features observed in the cuprate superconductors. While strong electron correlation plays an important role in producing high energy waterfall features in the cuprate superconductors, the revelation of the high energy anomalies in Sr2IrO4, which exhibits strong spin-orbit coupling and a moderate electron correlation, points to an unknown and novel route in generating exotic electronic excitations.

  17. Anomalous High-Energy Waterfall-Like Electronic Structure in 5 d Transition Metal Oxide Sr2IrO4 with a Strong Spin-Orbit Coupling.

    Science.gov (United States)

    Liu, Yan; Yu, Li; Jia, Xiaowen; Zhao, Jianzhou; Weng, Hongming; Peng, Yingying; Chen, Chaoyu; Xie, Zhuojin; Mou, Daixiang; He, Junfeng; Liu, Xu; Feng, Ya; Yi, Hemian; Zhao, Lin; Liu, Guodong; He, Shaolong; Dong, Xiaoli; Zhang, Jun; Xu, Zuyan; Chen, Chuangtian; Cao, Gang; Dai, Xi; Fang, Zhong; Zhou, X J

    2015-08-12

    The low energy electronic structure of Sr2IrO4 has been well studied and understood in terms of an effective Jeff = 1/2 Mott insulator model. However, little work has been done in studying its high energy electronic behaviors. Here we report a new observation of the anomalous high energy electronic structure in Sr2IrO4. By taking high-resolution angle-resolved photoemission measurements on Sr2IrO4 over a wide energy range, we have revealed for the first time that the high energy electronic structures show unusual nearly-vertical bands that extend over a large energy range. Such anomalous high energy behaviors resemble the high energy waterfall features observed in the cuprate superconductors. While strong electron correlation plays an important role in producing high energy waterfall features in the cuprate superconductors, the revelation of the high energy anomalies in Sr2IrO4, which exhibits strong spin-orbit coupling and a moderate electron correlation, points to an unknown and novel route in generating exotic electronic excitations.

  18. Electronic structure of hcp transition metals

    DEFF Research Database (Denmark)

    Jepsen, O.; Andersen, O. Krogh; Mackintosh, A. R.

    1975-01-01

    Using the linear muffin-tin-orbital method described in the previous paper, we have calculated the electronic structures of the hcp transition metals, Zr, Hf, Ru, and Os. We show how the band structures of these metals may be synthesized from the sp and d bands, and illustrate the effects...... of hybridization, relativistic band shifts, and spin-orbit coupling by the example of Os. By making use of parameters derived from the muffin-tin potential, we discuss trends in the positions and widths of the energy bands, especially the d bands, as a function of the location in the periodic table. The densities...... of states of the four metals are presented, and the calculated heat capacities compared with experiment. The Fermi surfaces of both Ru and Os are found to be in excellent quantitative agreement with de Haas-van Alphen measurements, indicating that the calculated d-band position is misplaced by less than 10...

  19. Energy transition: towards landscape devastation?

    International Nuclear Information System (INIS)

    Posokhow, Andre

    2013-09-01

    The author criticizes some aspects of the content of the French policy for energy transition. He states that the objective of reduction of greenhouse emissions is unreachable and moreover useless when China keeps on opening new coal-fired power stations. He states that temperatures do not increase any longer and that it is not sure that CO 2 emissions are responsible for past increases. He outlines that the power of wind turbines is only a quarter of their theoretical one, that replacing nuclear energy by wind energy would require the installation of 33.000 wind turbines. He states that objectives of energy saving are not credible, and that the energy mix predictions are fuzzy. He outlines contradictions about the nuclear power station life duration, states that the installation of 210 wind turbines per district would devastate the French landscape

  20. Shedding light on energy transition

    DEFF Research Database (Denmark)

    Markovska, Natasa; Duić, Neven; Mathiesen, Brian Vad

    2018-01-01

    -carbon technologies in energy supply, buildings, transport, and industry, as well as address other key issues like demand response, co-benefits to other energy policies objectives, the role of declining costs for renewables and markets - all needed to facilitate energy sector transition. This editorial outlines......Ever since 2002, when the first Conference on Sustainable Development of Energy, Water and Environment Systems (SDEWES) was held in Dubrovnik, the SDEWES conferences series has been providing a forum for world-wide scientists and those interested in learning about the sustainability of development...... into account its economic, environmental and social pillars, as well as methods for assessing and measuring sustainability of development, regarding energy, transport, water, food production and environment systems and their many combinations. SDEWES has maintained high publishing standard as nearly 1100...

  1. Three laws of energy transitions

    International Nuclear Information System (INIS)

    Bashmakov, Igor

    2007-01-01

    The paper formulates and explores a hypothesis on three general energy transition laws: the law of stable long-term energy costs to income ratio; the law of improving energy quality; and the law of growing energy productivity. These laws are essential for shaping long-term projections and checking for their consistency. All three are rooted in amazingly stable in time and universal across countries energy costs to income ratios. Limited energy purchasing power sets up thresholds, which, if exceeded, bring asymmetry to energy demand to price elasticity. The author believes, that the theoretical postulate on the substantial substitution among production factors, which is used in the production functions theory, may be incorrect. In reality, innovations mainly lead to the substitution of a low-quality production factor with the same yet of a better-quality. Improving energy quality with stable costs to income ratio is accompanied by growing energy productivity. Energy costs to income thresholds are indicators allowing for better projections of oil prices

  2. Which energy transition for France?

    International Nuclear Information System (INIS)

    Criqui, Patrick

    2014-01-01

    While recalling the five main objectives of the French bill project for energy transition, the author proposes some critical reflections. He notices that economic, political and financial means to reach the expected decrease of energy consumption are not sufficient. He notably comments the content of the various retained scenarios, discusses and explains the fact that there will always be a gap between the expected optimal energy efficiency and the obtained results: economic actors are not ready to make the required investments, France lacks of a culture of territorial energy governance, and a way of paying the produced carbon emissions is missing. He discusses the introduction of a carbon tax. He states that the Efficiency scenario seems difficult to be reached and briefly discusses the associated consequences. He finally outlines that the nuclear issue is not clearly addressed, either in the Ademe's scenario or by the bill project

  3. Correlated electron pseudopotentials for 3d-transition metals

    International Nuclear Information System (INIS)

    Trail, J. R.; Needs, R. J.

    2015-01-01

    A recently published correlated electron pseudopotentials (CEPPs) method has been adapted for application to the 3d-transition metals, and to include relativistic effects. New CEPPs are reported for the atoms Sc − Fe, constructed from atomic quantum chemical calculations that include an accurate description of correlated electrons. Dissociation energies, molecular geometries, and zero-point vibrational energies of small molecules are compared with all electron results, with all quantities evaluated using coupled cluster singles doubles and triples calculations. The CEPPs give better results in the correlated-electron calculations than Hartree-Fock-based pseudopotentials available in the literature

  4. Smart Energy Systems and Energy Transition

    International Nuclear Information System (INIS)

    Duic, N.

    2016-01-01

    Transition to decarbonized energy systems is becoming more attractive with fall of investment costs of renewables and volatile prices and political insecurity of fossil fuels. Improving energy efficiency, especially of buildings and transport, is important, but due to long life of buildings, it will be a slow way of decarbonization. The renewable energy resources are bountiful, especially wind and solar, while integrating them into current energy systems is proving to be a challenge. Solar has reached grid parity making it cheapest electricity source for retail customers in most of the World, creating new prosumer markets. It has started to reach cost parity in sunny countries, and soon solar energy will be cheapest everywhere. The limit of cheap and easy integration for wind is around 20% of yearly electricity generation, while a combined wind and solar may reach 30%. Going any further asks for implementation of completely free energy markets (involving day ahead, intraday and various reserve and ancillary services markets), demand response, coupling of wholesale and retail energy prices, and it involves integration between electricity, heat, water and transport systems. The cheapest and simplest way of increasing further the penetration of renewables is integrating power and heating/cooling systems through the use of district heating and cooling (which may be centrally controlled and may have significant heat storage capacity), since power to heat technologies are excellent for demand response. District cooling is of particular importance to historic cities that want to remove split systems from their facades. In countries with low heat demand water supply system may be used to increase the penetration of renewables, by using water at higher potential energy as storage media, or in dry climates desalination and stored water may be used for those purposes, and reversible hydro may be used as balancing technology. Electrification of personal car transport allows

  5. High energy leptons from muons in transit

    International Nuclear Information System (INIS)

    Bulmahn, Alexander; Reno, Mary Hall

    2010-01-01

    The differential energy distribution for electrons and taus produced from lepton pair production from muons in transit through materials is numerically evaluated. We use the differential cross section to calculate underground lepton fluxes from an incident atmospheric muon flux, considering contributions from both conventional and prompt fluxes. An approximate form for the charged current differential neutrino cross section is provided and used to calculate single lepton production from atmospheric neutrinos. We compare the fluxes of underground leptons produced from incident muons with those produced from incident neutrinos and photons from muon bremsstrahlung. We discuss their relevance for underground detectors.

  6. Electronic and thermodynamic properties of transition metal elements and compounds

    International Nuclear Information System (INIS)

    Haeglund, J.

    1993-01-01

    This thesis focuses on the use of band-structure calculations for studying thermodynamic properties of solids. We discuss 3d-, 4d- and 5d-transition metal carbides and nitrides. Through a detailed comparison between theoretical and experimental results, we draw conclusions on the character of the atomic bonds in these materials. We show how electronic structure calculations can be used to give accurate predictions for bonding energies. Part of the thesis is devoted to the application of the generalized gradient approximation in electronic structure calculations on transition metals. For structures with vibrational disorder, we present a method for calculating averaged phonon frequencies without using empirical information. For magnetic excitations, we show how a combined use of theoretical results and experimental data can yield information on magnetic fluctuations at high temperatures. The main results in the thesis are: Apart for an almost constant shift, theoretically calculated bonding energies for transition metal carbides and nitrides agree with experimental data or with values from analysis of thermochemical information. The electronic spectrum of transition metal carbides and nitrides can be separated into bonding, antibonding and nonbonding electronic states. The lowest enthalpy of formation for substoichiometric vanadium carbide VC 1-X at zero temperature and pressure occurs for a structure containing vacancies (x not equal to 0). The generalized gradient approximation improves theoretical calculated cohesive energies for 3d-transition metals. Magnetic phase transitions are sensitive to the description of exchange-correlation effects in electronic structure calculations. Trends in Debye temperatures can be successfully analysed in electronic structure calculations on disordered lattices. For the elements, there is a clear dependence on the crystal structure (e.g., bcc, fcc or hcp). Chromium has fluctuating local magnetic moments at temperatures well above

  7. Relaxation dynamics following transition of solvated electrons

    International Nuclear Information System (INIS)

    Barnett, R.B.; Landman, U.; Nitzan, A.

    1989-01-01

    Relaxation dynamics following an electronic transition of an excess solvated electron in clusters and in bulk water is studied using an adiabatic simulation method. In this method the solvent evolves classically and the electron is constrained to a specified state. The coupling between the solvent and the excess electron is evaluated via the quantum expectation value of the electron--water molecule interaction potential. The relaxation following excitation (or deexcitation) is characterized by two time scales: (i) a very fast (/similar to/20--30 fs) one associated with molecular rotations in the first solvation shell about the electron, and (ii) a slower stage (/similar to/200 fs), which is of the order of the longitudinal dielectric relaxation time. The fast relaxation stage exhibits an isotope effect. The spectroscopical consequences of the relaxation dynamics are discussed

  8. Energy storage. A challenge for energy transition

    International Nuclear Information System (INIS)

    Bart, Jean-Baptiste; Nekrasov, Andre; Pastor, Emmanuel; Benefice, Emmanuel; Brincourt, Thierry; Brisse, Annabelle; Cagnac, Albannie; Delille, Gauthier; Hinchliffe, Timothee; Lancel, Gilles; Jeandel, Elodie; Lefebvre, Thierry; Loevenbruck, Philippe; Penneau, Jean-Francois; Soler, Robert; Stevens, Philippe; Radvanyi, Etienne; Torcheux, Laurent

    2017-06-01

    Written by several EDF R and D engineers, this book aims at presenting an overview of knowledge and know-how of EDF R and D in the field of energy storage, and at presenting the different technologies and their application to electric power systems. After a description of the context related to a necessary energy transition, the authors present the numerous storage technologies. They distinguish direct storage of power (pumped storage water stations, compressed air energy storage, flywheels, the various electrochemical batteries, metal-air batteries, redox flow batteries, superconductors), thermal storage (power to heat, heat to power) and hydrogen storage (storage under different forms), and propose an overview of the situation of standardisation of storage technologies. In the next part, they give an overview of the main services provided by storage to the electric power system: production optimisation, frequency adjustment, grid constraint resolution, local smoothing of PV and wind production, supply continuity. The last part discusses perspectives regarding the role of tomorrow's storage in the field of electrical mobility, for emerging markets, and with respect to different scenarios

  9. Electronic topological transitions in Zn under compression

    Science.gov (United States)

    Kechin, Vladimir V.

    2001-01-01

    The electronic structure of hcp Zn under pressure up to 10 GPa has been calculated self-consistently by means of the scalar relativistic tight-binding linear muffin-tin orbital method. The calculations show that three electronic topological transitions (ETT's) occur in Zn when the c/a axial ratio diminishes under compression. One transition occurs at c/a~=1.82 when the ``needles'' appear around the symmetry point K of the Brillouin zone. The other two transitions occur at c/a~=3, when the ``butterfly'' and ``cigar'' appear simultaneously both around the L point. It has been shown that these ETT's are responsible for a number of anomalies observed in Zn at compression.

  10. First-principles determination of band-to-band electronic transition energies in cubic and hexagonal AlGaInN alloys

    Directory of Open Access Journals (Sweden)

    F. L. Freitas

    2016-08-01

    Full Text Available We provide approximate quasiparticle-corrected band gap energies for quaternary cubic and hexagonal AlxGayIn1–x–yN semiconductor alloys, employing a cluster expansion method to account for the inherent statistical disorder of the system. Calculated values are compared with photoluminescence measurements and discussed within the currently accepted model of emission in these materials by carrier localization. It is shown that bowing parameters are larger in the cubic phase, while the range of band gap variation is bigger in the hexagonal one. Experimentally determined transition energies are mostly consistent with band-to-band excitations.

  11. First-principles determination of band-to-band electronic transition energies in cubic and hexagonal AlGaInN alloys

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, F. L., E-mail: felipelopesfreitas@gmail.com; Marques, M.; Teles, L. K. [Grupo de Materiais Semicondutores e Nanotecnologia, Instituto Tecnológico de Aeronáutica, 12228-900 São José dos Campos, SP (Brazil)

    2016-08-15

    We provide approximate quasiparticle-corrected band gap energies for quaternary cubic and hexagonal Al{sub x}Ga{sub y}In{sub 1–x–y}N semiconductor alloys, employing a cluster expansion method to account for the inherent statistical disorder of the system. Calculated values are compared with photoluminescence measurements and discussed within the currently accepted model of emission in these materials by carrier localization. It is shown that bowing parameters are larger in the cubic phase, while the range of band gap variation is bigger in the hexagonal one. Experimentally determined transition energies are mostly consistent with band-to-band excitations.

  12. Energy Transition Initiative: Islands Playbook (Book)

    Energy Technology Data Exchange (ETDEWEB)

    2015-01-01

    The Island Energy Playbook (the Playbook) provides an action-oriented guide to successfully initiating, planning, and completing a transition to an energy system that primarily relies on local resources to eliminate a dependence on one or two imported fuels. It is intended to serve as a readily available framework that any community can adapt to organize its own energy transition effort.

  13. Nuclear energy in transition countries

    International Nuclear Information System (INIS)

    Knapp, V.

    2000-01-01

    Transition countries, respectively the countries that have in the year's 89/90 broken with the communist political and economy system are passing through difficult years. From their traditional markets within the closely interconnected socialist economy system, which has disintegrated, they have to reorient themselves to new, often saturated and sophisticated markets. To integrate into Europe as equal partners, rather then remain poor relatives, they must reduce this development gap in a reasonable time, not longer than 15 years. Slower pace would not give acceptable perspective to their young people and they would look for it elsewhere, thereby reducing creative forces for progress. Examples of economic development show that sustained growth of GDP is impossible without similar industrial growth, which, in turn, requires corresponding increase of energy use. In the same time these countries are the parts of densely populated European region and are subject to emission restriction of effluents with local or global effects. It is difficult to see how these countries could attain their development goals, whilst respecting their Kyoto obligations, without supplying increased energy demand from nuclear sources. (author)

  14. The energy transition in Sweden

    International Nuclear Information System (INIS)

    Cruciani, Michel

    2016-06-01

    relative to GDP it is exactly equal to the average for Western Europe (EU 15). Regarding emissions of greenhouse gases, the country had the lowest carbon footprint in 2013 within the EU15, both in terms of GDP and per capita use. Moreover, while environmental taxes raise the price of gas for industry substantially, they do not affect fuel prices overly. Nor do taxes prevent electricity prices from being among the cheapest in Europe, both for industry and for households. The current situation seems to be excellent. As a result, Sweden's political leaders have chosen to keep its underlying foundations and to carry out only moderate changes. Thus, while stating their preference for renewable energy, the major political parties have found common ground to reduce tax pressures on nuclear power, since 2014. In June 2016, the Parliamentary majority and opposition parties signed an agreement to modernize Sweden's fleet of reactors, thus further demonstrating their sense of compromise. This solution is designed to limit the rise in electricity costs and to lengthen the period available for alternative energy sources to reach maturity. In addition, the agreement extends the provisions promoting renewable power, but it also emphasizes the importance of managing the demand for capacity as well as the efficient use of electricity, giving consumers of power an active role, be they industrial or domestic users. In short, Sweden seems to have taken measure of the difficulties faced by some European countries which are already engaged in the energy transition and is trying to avoid them. Its political actors have been careful not to adopt excessively restrictive short-term goals and are content with general guidelines: they are betting on innovation to move forward. In this regard, Sweden has a major advantage, alongside the efforts made for several years, favouring research and development in a very structured way. The recent agreement consolidates these efforts. (author)

  15. Electron transfer by excited benzoquinone anions: slow rates for two-electron transitions.

    Science.gov (United States)

    Zamadar, Matibur; Cook, Andrew R; Lewandowska-Andralojc, Anna; Holroyd, Richard; Jiang, Yan; Bikalis, Jin; Miller, John R

    2013-09-05

    Electron transfer (ET) rate constants from the lowest excited state of the radical anion of benzoquinone, BQ(-•)*, were measured in THF solution. Rate constants for bimolecular electron transfer reactions typically reach the diffusion-controlled limit when the free-energy change, ΔG°, reaches -0.3 eV. The rate constants for ET from BQ(-•)* are one-to-two decades smaller at this energy and do not reach the diffusion-controlled limit until -ΔG° is 1.5-2.0 eV. The rates are so slow probably because a second electron must also undergo a transition to make use of the energy of the excited state. Similarly, ET, from solvated electrons to neutral BQ to form the lowest excited state, is slow, while fast ET is observed at a higher excited state, which can be populated in a transition involving only one electron. A simple picture based on perturbation theory can roughly account for the control of electron transfer by the need for transition of a second electron. The picture also explains how extra driving force (-ΔG°) can restore fast rates of electron transfer.

  16. Energy transition: what is it all about?

    International Nuclear Information System (INIS)

    Grandjean, Alain

    2013-01-01

    Illustrated by many graphs, figures, maps and tables, this Power Point document presents the main issues related to energy and concerning citizens and consumers, proposes a definition of energy transition, identifies the main levers for energy transition and the main questions raised by the objectives of energy transition: energy efficiency and sobriety, trajectory to reach the energy mix, choices related to renewable energies and to energy technologies, costs and financing, governance. Other challenges are outlined and discussed: governance, energy mix, industrial policy, competitiveness and jobs, energy management, household energy consumption and poverty, climate and energy, supply safety and trade balance, health and environmental impacts, price, cost, taxing, financing and macro-economic consistency. For each of these challenges, facts are highlighted and problems to be solved are identified

  17. Negawatt manifesto - Making energy transition a success

    International Nuclear Information System (INIS)

    Salomon, Thierry; Jedliczka, Marc; Marignac, Yves; Hessel, Stephane; Lovins, Amory

    2012-01-01

    For ten years, the Negawatt association has taken a fresh look at our ways of consuming and producing energy. After the realisation of its 2011 scenario, the association has wished to complete this work with a reflexion full of ideas and operational measures and addressed to all citizens and to decision-makers. This manifesto describes with pedagogy and lucidity a possible and desirable path to get out of our energy and climate crises. Contents: 1 - Energy in crisis; 2 - Energy in its all forms; 3 - From the approach to the scenario: preparing the energy transition; 4 - Buildings and energy transition; 5 - Key-sectors of the transition: transports, industry and agriculture; 6 - Advent of renewable energies; 7 - From the nuclear twilight to the renewable dawn; 8 - Costs and benefits of the energy transition; 9 - The 'true value' of energy; 10 - From the status time to the action one. A series of 26 graphs summarizes the Negawatt approach. (J.S.)

  18. An Institutional Approach to Understanding Energy Transitions

    Science.gov (United States)

    Koster, Auriane Magdalena

    Energy is a central concern of sustainability because how we produce and consume energy affects society, economy, and the environment. Sustainability scientists are interested in energy transitions away from fossil fuels because they are nonrenewable, increasingly expensive, have adverse health effects, and may be the main driver of climate change. They see an opportunity for developing countries to avoid the negative consequences fossil-fuel-based energy systems, and also to increase resilience, by leap-frogging-over the centralized energy grid systems that dominate the developed world. Energy transitions pose both challenges and opportunities. Obstacles to transitions include 1) an existing, centralized, complex energy-grid system, whose function is invisible to most users, 2) coordination and collective-action problems that are path dependent, and 3) difficulty in scaling up RE technologies. Because energy transitions rely on technological and social innovations, I am interested in how institutional factors can be leveraged to surmount these obstacles. The overarching question that underlies my research is: What constellation of institutional, biophysical, and social factors are essential for an energy transition? My objective is to derive a set of "design principles," that I term institutional drivers, for energy transitions analogous to Ostrom's institutional design principles. My dissertation research will analyze energy transitions using two approaches: applying the Institutional Analysis and Development Framework and a comparative case study analysis comprised of both primary and secondary sources. This dissertation includes: 1) an analysis of the world's energy portfolio; 2) a case study analysis of five countries; 3) a description of the institutional factors likely to promote a transition to renewable-energy use; and 4) an in-depth case study of Thailand's progress in replacing nonrenewable energy sources with renewable energy sources. My research will

  19. Coherence in electron energy loss spectrometry

    International Nuclear Information System (INIS)

    Schattschneider, P.; Werner, W.S.M.

    2005-01-01

    Coherence effects in electron energy loss spectrometry (EELS) and in energy filtering are largely neglected although they occur frequently due to Bragg scattering in crystals. We discuss how coherence in the inelastically scattered wave field can be described by the mixed dynamic form factor (MDFF), and how it relates to the density matrix of the scattered electrons. Among the many aspects of 'inelastic coherence' are filtered high-resolution images, dipole-forbidden transitions, coherence in plasma excitations, errors in chemical microanalysis, coherent double plasmons, and circular dichroism

  20. Energy transition in France and Germany

    International Nuclear Information System (INIS)

    Persem, Melanie

    2014-01-01

    This document presents some key figures and comparisons between the French and German energy plans: electricity mix, 2003-2013 evolution of installed power and of renewable electrical production, cost of energy transition (evolution of charges relative to contracts of renewable electricity purchasing agreement), 2004-2013 evolution employment in renewable energies industry, France-Germany power exchanges (France import balance of 9.8 TWh in 2013), electricity goals in the French and German energy transitions

  1. Electron spectroscopic investigation of metal–insulator transition in ...

    Indian Academy of Sciences (India)

    Unknown

    Electronic structure of transition metal (TM) oxides has been under detailed investi- ..... Scientific and Industrial Research, New Delhi for a fellowship. ... Maiti K 1998 Novel electronic structures in transition metal oxides, Ph D thesis, Solid.

  2. electron energy-loss spectroscopy

    International Nuclear Information System (INIS)

    Egerton, R.

    1997-01-01

    As part of a commemorative series of articles to mark the hundredth anniversary of the discovery of the electron, this article describes the use of electron energy-loss spectroscopy. The physical and chemical properties of materials can be studied by considering the energy that electrons use as they travel through a solid, often in conjunction with other analytical techniques. The technique is often combined with electron diffraction and high-resolution imaging and can be used to provide elemental identification down to the atomic scale. 6 figs

  3. Electron energy-loss spectroscopy

    International Nuclear Information System (INIS)

    Egerton, R.

    1997-01-01

    As part of the commemorative series of articles to mark the hundredth anniversary of the discovery of the electron, this article discusses electron energy-loss spectroscopy. The physical and chemical properties of materials can be studied by considering the energy that electrons use as they travel through a solid, often in conjunction with other analytical techniques. The technique is often combined with electron diffraction and high-resolution imaging and can be used to provide elemental identification down to the atomic scale. (UK)

  4. The OPECST and the energy transition

    International Nuclear Information System (INIS)

    Le Deaut, Jean-Yves

    2014-01-01

    The OPECST is the French Parliamentary Office of Assessment of Scientific and Technological Choices. It has been created in 1983. Its activities and operational modality are presented. The next part comments OPECST activities related to energy transition, evokes some reports published on different topics: the future of the nuclear sector, the perspectives of non conventional hydrocarbons, the possibilities of the use of hydrogen for energy storage. Several aspects are notably addressed: the technical conditions to be met for a successful energy transition, the role of nuclear energy in energy transition, the extension of nuclear reactor service lifetime, the opinion of the OPECST on some prospective scenarios (ADEME and Negawatt). The improvement of buildings thermal insulation is commented as a major element in energy transition, but the complexity of regulations and problems for investors are outlined, as well as the cost of renovation for households

  5. Energy transition and phasing out nuclear

    International Nuclear Information System (INIS)

    Laponche, Bernard

    2013-05-01

    In the first part of this report, the author outlines and comments the need of an energy transition in the world: overview of world challenges (world energy consumption and its constraints, a necessary energy transition, new actors and new responsibilities), and describes the German example of an energy transition policy. In the second part, he presents and discusses the main reasons for phasing out nuclear: description of a nuclear plant operation (fission and chain reaction, heat production, production of radioactive elements, how to stop a nuclear reactor), safety and risk issues (protection arrangements, risk and consequence of a nuclear accident), issue of radioactive wastes, relationship between civil techniques and proliferation of nuclear weapons. In a third part, the author proposes an overview of the energy issue in France: final energy consumption, electricity production and consumption, primary energy consumption, characteristics of the French energy system (oil dependency, electricity consumption, and high share of nuclear energy in electricity production). In a last part, the author addresses the issue of energy transition in a perspective of phasing out nuclear: presentation of the Negawatt scenario, assessments made by Global Chance, main programmes of energy transition

  6. Electron paramagnetic resonance of transition ions

    CERN Document Server

    Abragam, Anatole

    1970-01-01

    This book is a reissue of a classic Oxford text, and provides a comprehensive treatment of electron paramagnetic resonance of ions of the transition groups. The emphasis is on basic principles, with numerous references to publications containing further experimental results and more detailed developments of the theory. An introductory survey gives a general understanding, and a general survey presents such topics as the classical and quantum resonance equations, thespin-Hamiltonian, Endor, spin-spin and spin-lattice interactions, together with an outline of the known behaviour of ions of each

  7. Ab initio study of the RbSr electronic structure: Potential energy curves, transition dipole moments, and permanent electric dipole moments

    Energy Technology Data Exchange (ETDEWEB)

    Pototschnig, Johann V., E-mail: johann.pototschnig@tugraz.at; Krois, Günter; Lackner, Florian; Ernst, Wolfgang E., E-mail: wolfgang.ernst@tugraz.at [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz (Austria)

    2014-12-21

    Excited states and the ground state of the diatomic molecule RbSr were calculated by post Hartree-Fock molecular orbital theory up to 22 000 cm{sup −1}. We applied a multireference configuration interaction calculation based on multiconfigurational self-consistent field wave functions. Both methods made use of effective core potentials and core polarization potentials. Potential energy curves, transition dipole moments, and permanent electric dipole moments were determined for RbSr and could be compared with other recent calculations. We found a good agreement with experimental spectra, which have been obtained recently by helium nanodroplet isolation spectroscopy. For the lowest two asymptotes (Rb (5s {sup 2}S) + Sr (5s4d {sup 3}P°) and Rb (5p {sup 2}P°) + Sr (5s{sup 2} {sup 1}S)), which exhibit a significant spin-orbit coupling, we included relativistic effects by two approaches, one applying the Breit-Pauli Hamiltonian to the multireference configuration interaction wave functions, the other combining a spin-orbit Hamiltonian and multireference configuration interaction potential energy curves. Using the results for the relativistic potential energy curves that correspond to the Rb (5s {sup 2}S) + Sr (5s4d {sup 3}P°) asymptote, we have simulated dispersed fluorescence spectra as they were recently measured in our lab. The comparison with experimental data allows to benchmark both methods and demonstrate that spin-orbit coupling has to be included for the lowest states of RbSr.

  8. Ab initio study of the RbSr electronic structure: potential energy curves, transition dipole moments, and permanent electric dipole moments.

    Science.gov (United States)

    Pototschnig, Johann V; Krois, Günter; Lackner, Florian; Ernst, Wolfgang E

    2014-12-21

    Excited states and the ground state of the diatomic molecule RbSr were calculated by post Hartree-Fock molecular orbital theory up to 22 000 cm(-1). We applied a multireference configuration interaction calculation based on multiconfigurational self-consistent field wave functions. Both methods made use of effective core potentials and core polarization potentials. Potential energy curves, transition dipole moments, and permanent electric dipole moments were determined for RbSr and could be compared with other recent calculations. We found a good agreement with experimental spectra, which have been obtained recently by helium nanodroplet isolation spectroscopy. For the lowest two asymptotes (Rb (5s (2)S) + Sr (5s4d (3)P°) and Rb (5p (2)P°) + Sr (5s(2) (1)S)), which exhibit a significant spin-orbit coupling, we included relativistic effects by two approaches, one applying the Breit-Pauli Hamiltonian to the multireference configuration interaction wave functions, the other combining a spin-orbit Hamiltonian and multireference configuration interaction potential energy curves. Using the results for the relativistic potential energy curves that correspond to the Rb (5s (2)S) + Sr (5s4d (3)P°) asymptote, we have simulated dispersed fluorescence spectra as they were recently measured in our lab. The comparison with experimental data allows to benchmark both methods and demonstrate that spin-orbit coupling has to be included for the lowest states of RbSr.

  9. Phase stability and electronic structure of transition-metal aluminides

    International Nuclear Information System (INIS)

    Carlsson, A.E.

    1992-01-01

    This paper will describe the interplay between die electronic structure and structural energetics in simple, complex, and quasicrystalline Al-transition metal (T) intermetallics. The first example is the Ll 2 -DO 22 competition in Al 3 T compounds. Ab-initio electronic total-energy calculations reveal surprisingly large structural-energy differences, and show that the phase stability of both stoichiometric and ternary-substituted compounds correlates closely with a quasigap in the electronic density of states (DOS). Secondly, ab-initio calculations for the structural stability of the icosahedrally based Al 12 W structure reveal similar quasigap effects, and provide a simple physical explanation for the stability of the complex aluminide structures. Finally, parametrized tight-binding model calculations for the Al-Mn quasicrystal reveal a large spread in the local Mn DOS behavior, and support a two-site model for the quasicrystal's magnetic behavior

  10. Laser Assisted Free-Free Transition in Electron - Atom Collision

    Science.gov (United States)

    Sinha, C.; Bhatia, A. K.

    2011-01-01

    Free-free transition is studied for electron-Hydrogen atom system in ground state at very low incident energies in presence of an external homogeneous, monochromatic and linearly polarized laser field. The incident electron is considered to be dressed by the laser in a non perturbative manner by choosing the Volkov solutions in both the channels. The space part of the scattering wave function for the electron is solved numerically by taking into account the effect of electron exchange, short range as well as of the long range interactions. Laser assisted differential as well as elastic total cross sections are calculated for single photon absorption/emission in the soft photon limit, the laser intensity being much less than the atomic field intensity. A strong suppression is noted in the laser assisted cross sections as compared to the field free situations. Significant difference is noted in the singlet and the triplet cross sections.

  11. Electron-doping by hydrogen in transition-metal dichalcogenides

    Science.gov (United States)

    Oh, Sehoon; Im, Seongil; Choi, Hyoung Joon

    Using first-principles calculations, we investigate the atomic and electronic structures of 2H-phase transition-metal dichalcogenides (TMDC), 2H-MX2, with and without defects, where M is Mo or W and X is S, Se or Te. We find that doping of atomic hydrogen on 2H-MX2 induces electron doping in the conduction band. To understand the mechanism of this electron doping, we analyze the electronic structures with and without impurities. We also calculate the diffusion energy barrier to discuss the spatial stability of the doping. Based on these results, we suggest a possible way to fabricate elaborately-patterned circuits by modulating the carrier type of 2H-MoTe2. We also discuss possible applications of this doping in designing nano-devices. This work was supported by NRF of Korea (Grant No. 2011-0018306) and KISTI supercomputing center (Project No. KSC-2016-C3-0052).

  12. Technological Change during the Energy Transition

    NARCIS (Netherlands)

    van der Meijden, G.C.; Smulders, J.A.

    2014-01-01

    The energy transition from fossil fuels to alternative energy sources has important consequences for technological change and resource extraction. We examine these consequences by incorporating a non-renewable resource and an alternative energy source in a market economy model of endogenous growth

  13. TECHNOLOGICAL CHANGE during the ENERGY TRANSITION

    NARCIS (Netherlands)

    van der Meijden, Gerard; Smulders, Sjak

    2018-01-01

    The energy transition from fossil fuels to alternative energy sources has important consequences for technological change and resource extraction. We examine these consequences by incorporating a nonrenewable resource and an alternative energy source in a market economy model of endogenous growth

  14. Technological Change During the Energy Transition

    NARCIS (Netherlands)

    van der Meijden, G.C.; Smulders, Sjak A.

    2014-01-01

    The energy transition from fossil fuels to alternative energy sources has important consequences for technological change and resource extraction. We examine these consequences by incorporating a non-renewable resource and an alternative energy source in a market economy model of endogenous growth

  15. Electronic traffic signs: Reflecting upon its transition

    Energy Technology Data Exchange (ETDEWEB)

    Arbaiza Martin, A.E.; Alba, A.L.; Hernando Mazon, A.; Blanch Mico, M.T.

    2016-07-01

    In our days we face a fundamental issue concerning road signs. We may display contents in vertical and horizontal format (static signs, variable message signs, road markings), either on a post, a gantry or a dashboard. And we foresee a coming age where the excellent matrix resolution of painted signs will be truly approached by the resolution of full matrix displays. But we also risk a babel context threatening the universal approach encouraged by international catalogues as the 1968 Convention (ECE/TRANS/196, 2007). And the fundamental risk comes from our decisions regarding how the transition from the contents and formats displayed on static message signs to the ones displayed on electronic signs (in gantries or dashboards) should be. Our work explores this issue specifically, considering the transition from Advance Direction Signs (static message signs, class G, 1 in the 1968 Convention) to what could be termed Advance Location Signs (signs concerning the location of variable events with regards to certain landmarks) developed as an adaptation of the G, 1 class to electronic traffic signs.(Author)

  16. Late time phase transition as dark energy

    Indian Academy of Sciences (India)

    Abstract. We show that the dark energy field can naturally be described by the scalar condensates of a non-abelian gauge group. This gauge group is unified with the standard model gauge groups and it has a late time phase transition. The small phase transition explains why the positive acceleration of the universe is ...

  17. Energy transitions research: Insights and cautionary tales

    International Nuclear Information System (INIS)

    Grubler, Arnulf

    2012-01-01

    This short essay first reviews the pioneers of energy transition research both in terms of data as well as theories. Three major insights that have emerged from this nascent research fields are summarized highlighting the importance of energy end-use and services, the lengthy process of transitions, as well as the patterns that characterize successful scale up of technologies and industries that drive historical energy transitions. The essay concludes with cautionary notes also derived from historical experience. In order to trigger a next energy transition policies and innovation efforts need to be persistent and continuous, aligned, as well as balanced. It is argued that current policy frameworks in place invariably do not meet these criteria and need to change in order to successfully trigger a next energy transition towards sustainability. - Highlights: ► Includes the first literature review of early energy transition research. ► Summarizes three major research findings from the literature. ► Reviews policy implications of recent case studies of energy technology innovation. ► Argues that current policy frameworks are deficient in view of above lessons.

  18. Triggering of 178Hfm2 by photoinduced electron transition

    Directory of Open Access Journals (Sweden)

    A. Ya. Dzyublik

    2013-03-01

    Full Text Available We considered the NEET (nuclear excitation by electron transition as a possible triggering mechanism of the isomer 178Hfm2 during ionization of the L3 atomic shell by x-rays. This isomer is assumed to be excited into an intermediate state by E1 electronic transition between M5 and L3 shells. Simple nonrelativistic formulas are derived for the NEET probability. The estimations show the probability to be less than the experimental data of [1] by one order of magnitude. The intermediate level is found to decay bypassing the isomeric level 16+, if the nucleus attributes a triaxial shape in the state and, besides, there exists a level 13- shifted with respect to 15- by 400 keV. We have shown also that the NEET cross section as a function of the energy of x-ray photons , has to accept constant value above the L photoionization threshold in contrast to narrow peak observed by [1].

  19. Toward an energy transition period?

    International Nuclear Information System (INIS)

    Raineau, L.

    2011-01-01

    Energy is often only perceived in a very strict technical sense. This is may be the reason why renewable energies are frequently apprehend as mere substitutes for fossil energy, especially when they are centrally exploited, as in central solar or wind power stations. They are therefore supposed to replace this polluting energy within an unchanged technical and social context. Their very slight ability to meet this objective is related to this unrealistic challenge. Indeed, renewable energies demand new technical, political, economic and social systems, radically different from those operating with fossil and nuclear energies. To be effective and meaningful, they need new institutional framework, which would give a true decision-making power to citizen, allow a real decentralization and a local economy in the field of energy. Therefore, the main innovation these energies requires (and allows) is not technological, but political, economic and institutional. Here is the main challenge for these new, and in the mean time traditional, energies in our modern society. Mostly because it changes our relationship with Nature, renewable energies open new collective representations of environmental and energy problems facing nowadays society. We will at last illustrate our argument with the example of those ecological neighborhoods (or 'eco-villages') that are now developing in a growing number of cities all over the world. (author)

  20. Energy transition - The real choices

    International Nuclear Information System (INIS)

    Chevalier, Jean-Marie; Cruciani, Michel; Geoffron, Patrice

    2013-01-01

    In this book, the authors propose an overview of assets and weaknesses of the French energy model, i.e. expertise and a unique energy patrimony on the one side, and a too strong dependence on hydrocarbons, an insufficient share of renewable energies, and prices which do not reflect the market reality on the other side. While addressing currently debated issues, the authors aim at proposing some clues and answers to different questions related to the interdiction of shale gas, to the role of nuclear energies in front of climate change, to the cost of development of renewable energies. They also discuss how to make the French energy system more efficient and to struggle against growing energy poverty

  1. Germany: energy transition or revolution

    International Nuclear Information System (INIS)

    Boulanger, V.

    2013-01-01

    Germany has decided to phase out nuclear power by 2022 but it wants also to get rid of fossil energies by 2050. Those ambitious goals imply to be able to cut by half the demand for primary energy by 2050 which will be only possible if the need for building heating is cut by 80%, the constraint on transport is less important: one million of electrical vehicles will have to be on the road by 2020 and 3 millions 10 years later. In 2012 the production of electricity was made mainly from coal (44.7%), renewable energies (21.9%), nuclear energy (16%), natural gas (11.3%) and other energies (fuel...) (6.1%). Today the renewable energy sector is a major industrial sector in Germany, it represents about 382000 jobs directly or indirectly, it means more than the sector of conventional energies. (A.C.)

  2. Mechanical and electronic properties of Janus monolayer transition metal dichalcogenides

    Science.gov (United States)

    Shi, Wenwu; Wang, Zhiguo

    2018-05-01

    The mechanical and electronic properties of Janus monolayer transition metal dichalcogenides MXY (M  =  Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W; X/Y  =  S, Se, Te) were investigated using density functional theory. Results show that breaking the out-of-plane structural symmetry can be used to tune the electronic and mechanical behavior of monolayer transition metal dichalcogenides. The band gaps of monolayer WXY and MoXY are in the ranges of 0.16–1.91 and 0.94–1.69 eV, respectively. A semiconductor to metallic phase transition occurred in Janus monolayer MXY (M  =  Ti, Zr and Hf). The monolayers MXY (M  =  V, Nb, Ta and Cr) show metallic characteristics, which show no dependence on the structural symmetry breaking. The mechanical properties of MXY depended on the composition. Monolayer MXY (M  =  Mo, Ti, Zr, Hf and W) showed brittle characteristic, whereas monolayer CrXY and VXY are with ductile characteristic. The in-plane stiffness of pristine and Janus monolayer MXY are in the range between 22 and 158 N m‑1. The tunable electronic and mechanical properties of these 2D materials would advance the development of ultra-sensitive detectors, nanogenerators, low-power electronics, and energy harvesting and electromechanical systems.

  3. Pressure induced phase transition behaviour in -electron based ...

    Indian Academy of Sciences (India)

    The present review on the high pressure phase transition behaviour of ... For instance, closing of energy gaps lead to metal–insulator transitions [4], shift in energy ... systematic study of the pressure induced structural sequences has become ...

  4. The Greenpeace 2013 scenario for energy transition

    International Nuclear Information System (INIS)

    Cormier, Cyrille; Teske, Sven

    2013-01-01

    After a synthesis of the Greenpeace scenario for energy transition, this report presents the French current energy landscape: structure of the energy system, greenhouse gas emissions and nuclear risks, main social and economic challenges, and search for a political ambition (from the Grenelle de l'Environnement to the current debate on energy). Then, after having outlined that energy transition must be decided now, the report presents the scenario hypotheses: studies used to develop the scenario, macro-economic and technical-economic hypotheses. The scenario is then presented in terms of possible trajectory, of energy demand (global evolution per sector), of energy production (electricity, heat, mobility), and of CO 2 assessment and nuclear wastes. Scenarios are compared in social and economic terms, more particularly in terms of investments in electricity and heat production systems, of electricity production costs and electricity bill, of energy independence, and of jobs in the electricity and heat sectors

  5. From black to green energy. Geopolitics of global energy transition

    International Nuclear Information System (INIS)

    Slingerland, S.; Van Geuns, L.; Van der Linde, C.

    2008-05-01

    The transition to a global low-carbon energy sector is on the agenda of policymakers in the Netherlands, Europe and world-wide. However, the way in which the international political discussion takes place makes it far from clear that such a transition will indeed take place. Conflicts of interest between climate concerns, energy security, access to energy and profits made from fossil fuels should be analysed more properly and taken into account in international energy and climate negotiations in order to prevent that an energy crisis will be the only way forward towards a low-carbon energy sector. [nl

  6. Renewable energies and energy transition in Germany

    International Nuclear Information System (INIS)

    Persem, Melanie

    2014-01-01

    This document presents some key figures about the German national energy plan: the 2013 coalition contract and the 2014-2017 government priorities, the security of energy supplies and the reflections about an evolution of the existing mechanism, the legal aspects of the renewable energies support mechanism (EEG law and its amendments, 2014 law reform, goals, direct selling, bids solicitation, self-consumer EEG contribution, exemptions redesigning), the energy-mix comparison between Germany and France, the 2003-2013 evolution of the renewable power generation, the German photovoltaic and wind power parks (installed power, geographical distribution, capacity), and the evolution of electricity prices for the industry and for households between 1998 and 2013

  7. Gas, the energy for transition?

    International Nuclear Information System (INIS)

    Pigenet, Yaroslav

    2014-01-01

    The author describes gas as the less polluting fossil energy. He outlines that new gas fields have been discovered, notably non conventional gas fields. He notices that whatever conventional or not conventional, a gas field produces methane, and that there is therefore no difference for the end user. However, he notices that reserve assessments by the IAE are a matter of discussion, and that hydraulic fracturing has resulted in important environmental and human damages. Anyway, gas will be needed to face energy demand

  8. Structural and electronic phase transitions of ThS2 from first-principles calculations

    International Nuclear Information System (INIS)

    Guo, Yongliang; Wang, Changying; Qiu, Wujie; Ke, Xuezhi

    2016-01-01

    Performed a systematic study using first-principles methods of the pressure-induced structural and electronic phase transitions in ThS_2, which may play an important role in the next generation nuclear energy fuel technology.

  9. User Innovators in the Smart Energy Transition

    DEFF Research Database (Denmark)

    Nyborg, Sophie; Borch, Kristian; Bentzen, Martin Mose

    Notions of "smart energy systems" are pervasive in discussions of a low carbon transition and much work is devoted to developing "smart energy technologies" and analyzing their economic potential. However, users, i.e. civil society receive only little attention and are mainly described as "energy...... consumers". The aim of this research project is to explore how civil society can get a more active role in the transition towards a low carbon energy system. Through qualitative case-study methods and scenario work, we explore the role of "energy users" for the innovative design and development of large...... technological systems. We ask whether the envisioned smart energy systems have potential to support more active innovation roles for the individuals using energy systems than what have been described by previous studies. Moreover, we discuss whether and how such roles allow for a democratic as well as socially...

  10. Household transitions to energy efficient lighting

    International Nuclear Information System (INIS)

    Mills, Bradford; Schleich, Joachim

    2014-01-01

    New energy efficient lighting technologies can significantly reduce household electricity consumption, but adoption has been slow. A unique dataset of German households is used in this paper to examine the factors associated with the replacement of old incandescent lamps (ILs) with new energy efficient compact fluorescent lamps (CFLs) and light emitting diodes (LEDs). The ‘rebound’ effect of increased lamp luminosity in the transition to energy efficient bulbs is analyzed jointly with the replacement decision to account for household self-selection in bulb-type choice. Results indicate that the EU ban on ILs accelerated the pace of transition to CFLs and LEDs, while storage of bulbs significantly dampened the speed of the transition. Higher lighting needs and bulb attributes like energy efficiency, environmental friendliness, and durability spur IL replacement with CFLs or LEDs. Electricity gains from new energy efficient lighting are mitigated by 23% and 47% increases in luminosity for CFL and LED replacements, respectively. Model results suggest that taking the replacement bulb from storage and higher levels of education dampen the magnitude of these luminosity rebounds in IL to CFL transitions. - Highlights: • EU ban on ILs has fostered transitions to energy efficient lighting • Energy efficient, environmentally friendly, and durable lighting preferences make CFL and LED transitions more likely • Indicators of greater lighting needs are associated with higher propensities to replace ILs with CFLs and LEDs • For residential lighting, the rebound effect manifests itself through increases in luminosity • In IL to CLF transitions luminosity increases are lower with higher levels of education

  11. European leadership in the energy transition

    International Nuclear Information System (INIS)

    Trannoy, Alain; Aussilloux, Vincent

    2017-01-01

    President Trump's decision to withdraw from the Paris Agreement has led to a fragmentation in the US effort to see through the energy transition, with some states supporting it and others remaining committed to intensive fossil fuel use. This predicament presents the European Union with a unique opportunity to become the global leader in green energy technologies

  12. Modelling the energy transition in cities

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Felix [Wuppertal Univ. (Germany). Dept. of Civil Engineering; Schwarze, Bjoern; Spiekermann, Klaus; Wegener, Michael [Spiekermann und Wegener Urban and Regional Research, Dortmund (Germany)

    2013-09-01

    The history of cities is a history of energy transitions. In the medieval city heating and cooking occurred with wood and peat. The growth of the industrial city in the 19th century was built on coal and electricity. The sprawling metropolis of the 20th century was made possible by oil and gas. How will the city of the 21st century look after the next energy transition from fossil to renewable energy? This paper reports on the extension of an urban land-use transport interaction model to a model of the energy transition in the Ruhr Area, a five-million agglomeration in Germany. The paper presents the planned model extensions and how they are to be integrated into the model and shows first preliminary results.

  13. Energy balance in processes of transition radiation

    International Nuclear Information System (INIS)

    Vladimirov, S.V.; Tsytovich, V.N.

    1985-01-01

    The authors consider the transition radiation arising when a charged particle crosses an interface between two nonabsorbing media. It is shown that energy balance is observed under these circumstances. The fulfillment of energy balance in transition radiation for nonabsorbing media is rigorously demonstrated. This allows one to find the energy of the transition radiation from the change in the energy of the intrinsic field of the charge and the work of forces for volume waves, which in a number of cases of complicated configurations may prove to be considerably simpler than a direct calculation of the radiation power. For surface waves, a calculation of the work of forces enables one to determine the radiation power directly

  14. Electronic specific heat of transition metal carbides

    International Nuclear Information System (INIS)

    Conte, R.

    1964-07-01

    The experimental results that make it possible to define the band structure of transition metal carbides having an NaCI structure are still very few. We have measured the electronic specific heat of some of these carbides of varying electronic concentration (TiC, either stoichiometric or non-stoichiometric, TaC and mixed (Ti, Ta) - C). We give the main characteristics (metallography, resistivity, X-rays) of our samples and we describe the low temperature specific heat apparatus which has been built. In one of these we use helium as the exchange gas. The other is set up with a mechanical contact. The two use a germanium probe for thermometer. The measurement of the temperature using this probe is described, as well as the various measurement devices. The results are presented in the form of a rigid band model and show that the density of the states at the Fermi level has a minimum in the neighbourhood of the group IV carbides. (author) [fr

  15. Widening energy access in Africa: Towards energy transition

    International Nuclear Information System (INIS)

    Sokona, Youba; Mulugetta, Yacob; Gujba, Haruna

    2012-01-01

    The discussion to widen access to modern energy services has been influential in shaping some of the discussions on energy at the international level. The practice of widening modern energy services access to the poor in Africa is complex, and exacerbated by the dual nature of the energy system across Sub-Saharan Africa where traditional and modern energy systems and practices co-exist. This presents major challenges for policy makers who have to contend with a fragmented energy system, which requires the mobilisation of an array of actors at cross-sectoral levels in order to develop effective institutions and implement innovative policy frameworks. This paper further argues that, the ‘energy access’ discussion needs to take place in the context of energy transitions, giving due consideration to the productive sector as an important vehicle for change. As the link between energy and development is context specific, each African country needs to chart its own energy transition pathway into the future, and there are ample lessons that they can draw from previous energy transitions. - Highlights: ► Lack of access to modern energy services in Africa is an impediment to socio-economic development. ► Widening modern energy services access to the poor in Africa is complex. ► A broader approach to address the ‘energy access’ discourse is required. ► Each African country needs to chart its own energy transition pathway. ► Both fossil and renewable energy systems would be needed for a transition to modern energy sources.

  16. Electronic computer prediction of properties of binary refractory transition metal compounds on the base of their simplificated electronic structure

    International Nuclear Information System (INIS)

    Kutolin, S.A.; Kotyukov, V.I.

    1979-01-01

    An attempt is made to obtain calculation equations of macroscopic physico-chemical properties of transition metal refractory compounds (density, melting temperature, Debye characteristic temperature, microhardness, standard formation enthalpy, thermo-emf) using the method of the regression analysis. Apart from the compound composition the argument of the regression equation is the distribution of electron bands of d-transition metals, created by the energy electron distribution in the simplified zone structure of transition metals and approximated by Chebishev polynoms, by the position of Fermi energy on the map of distribution of electron band energy depending upon the value of quasi-impulse, multiple to the first, second and third Brillouin zone for transition metals. The maximum relative error of the regressions obtained as compared with the literary data is 15-20 rel.%

  17. Transition radiation electron beam diagnostic study at ATF

    International Nuclear Information System (INIS)

    Qiu, X.Z.; Wang, X.J.; Batchelor, K.; Ben-Zvi, I.

    1995-01-01

    Recently we have started a program to develop transition radiation based electron beam diagnostics at the Accelerator Test Facility at Brookhaven National Laboratory. In this paper, we will discuss a technique to estimate the lower limit in electron beam divergence measurement with single foil transition radiation and two-foil transition radiation interferometer. Preliminary experimental data from 4.5 MeV electron beam will be presented

  18. Hot Electron Photoemission from Plasmonic Nanostructures: The Role of Surface Photoemission and Transition Absorption

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Zhukovsky, Sergei; Ikhsanov, Renat Sh

    2015-01-01

    We study mechanisms of photoemission of hot electrons from plasmonic nanoparticles. We analyze the contribution of "transition absorption", i.e., loss of energy of electrons passing through the boundary between different materials, to the surface mechanism of photoemission. We calculate photoemis......We study mechanisms of photoemission of hot electrons from plasmonic nanoparticles. We analyze the contribution of "transition absorption", i.e., loss of energy of electrons passing through the boundary between different materials, to the surface mechanism of photoemission. We calculate...... photoemission rate and transition absorption for nanoparticles surrounded by various media with a broad range of permittivities and show that photoemission rate and transition absorption follow the same dependence on the permittivity. Thus, we conclude that transition absorption is responsible...

  19. 5th International Workshop on Desorption Induced by Electronic Transitions

    CERN Document Server

    Jennison, Dwight R; Stechel, Ellen B; DIET V; Desorption induced by electronic transitions

    1993-01-01

    This volume in the Springer Series on Surface Sciences presents a recent account of advances in the ever-broadening field of electron-and photon-stimulated sur­ face processes. As in previous volumes, these advances are presented as the proceedings of the International Workshop on Desorption Induced by Electronic Transitions; the fifth workshop (DIET V) was held in Taos, New Mexico, April 1-4, 1992. It will be abundantly clear to the reader that "DIET" is not restricted to desorption, but has for several years included photochemistry, non-thermal surface modification, exciton self-trapping, and many other phenomena that are induced by electron or photon bombardment. However, most stimulated surface processes do share a common physics: initial electronic excitation, localization of the excitation, and conversion of electronic energy into nuclear kinetic energy. It is the rich variation of this theme which makes the field so interesting and fruitful. We have divided the book into eleven parts in orde...

  20. Mediterranean energy transition: 2040 scenario. Executive summary

    International Nuclear Information System (INIS)

    Ben Jannet Allal, Houda; Guarrera, Lisa; Karbuz, Sohbet; Menichetti, Emanuela; Lescoeur, Bruno; El Agrebi, Hassen; Harrouch, Hamdi; Campana, Dominique; Greaume, Francois; Bedes, Christelle; Bolinches, Christine; Meraud, Thierry; Tappero, Denis; Bosseboeuf, Didier; Lechevin, Bruno; Abaach, Hassan; Damasiotis, Markos; Darras, Marc; Hajjaji, Mourad; Keramane, Abdenour; Khalfallah, Ezzedine; Mourtada, Adel; Osman, Nejib

    2016-06-01

    The stakes of embarking upon a Mediterranean Energy Transition is essential for countries from both shores of the Mediterranean, especially taking into account the increasing demographics (+105 million by 2040) and the fast growing energy demand in an increasingly constrained context both in terms of energy availability and environmental impacts of conventional energy sources uses. There is a huge, but yet untapped, potential for energy efficiency and renewable energy sources, especially in the South Mediterranean region. By improving energy efficiency and deploying renewables on a large scale, the Mediterranean region would reduce tensions on energy security for importing countries, improve opportunities for exporting ones and reduce energy costs and environmental damages for the whole region. Embarking on an energy transition path will also help improve social welfare in the region and contribute to job creation, among other positive externalities. OME regularly conducts prospective works to 2040, assessing the impact of prolonging current energy trends. Under this Business-As-Usual or so-called 'Conservative' Scenario the situation would evolve critically on all counts over the next 25 years: doubling of energy demand and tripling of electricity consumption, soaring infrastructure and import bills (+443 GW to be installed and doubling of the fossil-fuel imports) and a critical rise in carbon emissions (+45%). Such a scenario, based essentially on fossil fuels, would put further strain on the environment and exacerbate geopolitical tensions in the region. A change of energy trajectory is therefore necessary for all Mediterranean countries to help change current trends and to increase efforts promoting energy efficiency and renewable energies. In this context, MEDENER and OME, based on the 2030-2050 visions of ADEME and the prospective tools of OME, have decided to jointly investigate a Mediterranean Energy Transition Scenario, an ambitious scenario that

  1. Smart Grids - The Playground of Energy Transition

    International Nuclear Information System (INIS)

    Hribernik, W.

    2016-01-01

    In Europe, energy transition is already in full swing. In the power supply, wind and solar energy play an increasingly important role. The fluctuating feed-in of these often also decentral energy sources can lead to capacity problems at different network levels. Intelligent electrical networks, so called "smart grids", optimally optimize system capacities through ongoing coordination between producers. From a global point of view, the aim is to set a set of measures that meet the most important target parameters for the smart networks: maximum integration of renewable energy sources, maximum security of supply and an optimal functioning of the energy markets in an economically efficient manner. (rössner) [de

  2. Transition Towards Energy Efficient Machine Tools

    CERN Document Server

    Zein, André

    2012-01-01

    Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The ...

  3. Implementing energy transition - A legal deciphering

    International Nuclear Information System (INIS)

    Bain-Thouverez, Justine; Romi, Raphael; Chautard, Thomas

    2016-07-01

    As the French law on energy transition reconfigures many parameters of implementation of public action, the authors propose a cross-referenced reading of this law, of the law for new organisation of territories (NOTRe) in its environmental dimension, and of the regulation which results from these legal standards, in order to have a better view on public action in terms of abilities, and of action and financial levers. In a first part, the author discuss the relationships of energy transition with State, regions, districts, EPCI (communal collaboration public body), communes, and public bodies. In the second part, they address the new levers for action, and finally address the financing of energy transition (financing funds, third-party financing companies)

  4. No energy transition without a smart network

    International Nuclear Information System (INIS)

    Funnell, Ian

    2015-01-01

    Influencing the demand for energy and modifying the means of production while introducing new uses are part of a quite complicated equation. Smart electricity grids are very important for solving this equation and indispensable for the energy transition. Since they deeply alter jobs in this sector, they are forcing industrialists to draw up a genuine strategy. ABB is convinced that a successful energy transition involves using three levers: the evolution of consumer behavior patterns; the regulatory and legal framework; and the deployment of technical solutions. As for the last, ABB can, owing to its strong experiences and skills, advise decision-makers about the changes necessary in existing networks so as to open the way for this transition toward a sustainable world

  5. Microwave instability across the transition energy

    International Nuclear Information System (INIS)

    Lee, S.Y.; Wang, J.M.

    1985-01-01

    It is well known that during the acceleration of hadrons in a storage ring, the beam always goes above the microwave instability threshold near the transition energy γ /SUB t/ . The reason is that the longitudinal revolution frequency spread of the beam which otherwise provides Landau damping vanishes at the transition energy. The amount of the beam dilution near the transition energy is determined by /tau/ /SUB th/ , the length of time when the beam stays unstable, and the growth rate of the instability. It is pointed out in this paper that /tau/ /SUB th/ is proportional to the fourth power of γ /SUB t/ , and thus the choice of a large γ /SUB t/ is not desirable from this point of view. An analysis is also given of the microwave instability induced beam dilution for the proposed Relativistic Heavy Ion Collider at BNL

  6. Microwave instability across the transition energy

    International Nuclear Information System (INIS)

    Lee, S.Y.; Wang, J.M.

    1985-01-01

    It is well known that during the acceleration of hadrons in a storage ring, the beam always goes above the microwave instability threshold near the transition energy γ/sub t/. The reason is that the longitudinal revolution frequency spread of the beam which otherwise provides Landau damping vanishes at the transition energy. The amount of the beam dilution near the transition energy is determined by tau/sub th/, the length of time when the beam stays unstable, and the growth rate of the instability. It is pointed out in this paper that tau/sub th/ is proportional to the fourth power of γ/sub t/, and thus the choice of a large γ/sub t/ is not desirable from this point of view. An analysis is also given of the microwave instability induced beam dilution for the proposed Relativistic Heavy Ion Collider at BNL

  7. High energy polarized electron beams

    International Nuclear Information System (INIS)

    Rossmanith, R.

    1987-01-01

    In nearly all high energy electron storage rings the effect of beam polarization by synchrotron radiation has been measured. The buildup time for polarization in storage rings is of the order of 10 6 to 10 7 revolutions; the spins must remain aligned over this time in order to avoid depolarization. Even extremely small spin deviations per revolution can add up and cause depolarization. The injection and the acceleration of polarized electrons in linacs is much easier. Although some improvements are still necessary, reliable polarized electron sources with sufficiently high intensity and polarization are available. With the linac-type machines SLC at Stanford and CEBAF in Virginia, experiments with polarized electrons will be possible

  8. Diffraction of high energy electrons

    International Nuclear Information System (INIS)

    Bourret, A.

    1981-10-01

    The diffraction of electrons by a crystal is examined to study its structure. As the electron-substance interaction is strong, it must be treated in a dynamic manner. Using the N waves theory and physical optics the base equations giving the wave at the outlet are deduced for a perfect crystal and their equivalence is shown. The more complex case of an imperfect crystal is then envisaged in these two approaches. In both cases, only the diffraction of high energy electrons ( > 50 KeV) are considered since in the diffraction of slow electrons back scattering cannot be ignored. Taking into account an increasingly greater number of beams, through fast calculations computer techniques, enables images to be simulated in very varied conditions. The general use of the Fast Fourier Transform has given a clear cut practical advantage to the multi-layer method [fr

  9. Theory of coherent transition radiation generated by ellipsoidal electron bunches

    NARCIS (Netherlands)

    Root, op 't W.P.E.M.; Smorenburg, P.W.; Oudheusden, van T.; Wiel, van der M.J.; Luiten, O.J.

    2007-01-01

    We present the theory of coherent transition radiation (CTR) generated by ellipsoidal electron bunches. We calculate analytical expressions for the electric field spectrum, the power spectrum, and the temporal electric field of CTR, generated by cylindrically symmetric ellipsoidal electron bunches

  10. Why must there be an energy transition?

    International Nuclear Information System (INIS)

    Schwarz, Virginie; Lavergne, Gerard

    2015-01-01

    The energy transition is a response to the environmental and climate issues now facing our planet. It is also a source of growth and jobs, both very important during the current economic slowdown. Far from being a preoccupation of France alone, this transition toward green growth brings together a vast international movement bearing a new awareness by scientists, citizens and their representatives. Accordingly, changes in the 'energy model' are to be made through joint efforts and the reinforced role to be played by citizens and local authorities for the sake of the environment and well-being and with the ambition of addressing the new century's main environmental issues

  11. For a rational energy transition based on nuclear energy

    International Nuclear Information System (INIS)

    Chalmin, Philippe

    2014-06-01

    After having recalled the meaning of the concept of energy transition, and stated that this concept is a fuzzy one, this paper addresses the issue of the future of energy through the concept of Energy returned on Energy invested (EROI). It discusses this approach by outlining that energy is the initial driver of economy, and by showing that only hydroelectricity, coal, nuclear and wind energy have a sufficient return rate, and that shale gas is an energy source for the short and medium term. Then, based on data related to world energy resources and consumption, to electric power production from various sources, to pollution health impacts, to electricity prices for industries and for households, it discusses the sustainability of the energy mix regarding energy reserves, health issues, and economic issues. Some examples (Spain, Germany) illustrate economic problems faced by some renewable energies. Finally, the authors outline that, thanks to its nuclear policy, France is the western country which is the most committed in energy transition. Some proposals are made to support nuclear energy, to reduce the use of fossil energies, to launch an ambitious research policy (on energy storage, on photovoltaic energy, on CO 2 hydrogenation, on hydrogen as a fuel), in favour of energy mixes decided at national levels in Europe

  12. Structural phase transition and electronic properties in samarium chalcogenides

    Energy Technology Data Exchange (ETDEWEB)

    Panwar, Y. S., E-mail: yspanwar2011@gmail.com [Department of Physics, Govt. New Science College Dewas-455001 (India); Aynyas, Mahendra [Department of Physics, C.S.A. Govt. P.G. College, Sehore, 466001 (India); Pataiya, J.; Sanyal, Sankar P. [Department of Physics, Barkatullah University, Bhopal, 462026 (India)

    2016-05-06

    The electronic structure and high pressure properties of samarium monochalcogenides SmS, SmSe and SmTe have been reported by using tight binding linear muffin-tin-orbital (TB-LMTO) method within the local density approximation (LDA). The total energy as a function of volume is evaluated. It is found that these monochalcogenides are stable in NaCl-type structure under ambient pressure. We predict a structural phase transition from NaCl-type (B{sub 1}-phase) structure to CsCl-type (B{sub 2}-type) structure for these compounds. Phase transition pressures were found to be 1.7, 4.4 and 6.6 GPa, for SmS, SmSe and SmTe respectively. Apart from this, the lattice parameter (a{sub 0}), bulk modulus (B{sub 0}), band structure (BS) and density of states (DOS) are calculated. From energy band diagram we observed that these compounds exhibit metallic character. The calculated values of equilibrium lattice parameter and phase transition pressure are in general good agreement with available data.

  13. Magnetic energy analyser for slow electrons

    International Nuclear Information System (INIS)

    Limberg, W.

    1974-08-01

    A differential spectrometer with high time and energy resolution has been developed using the principle of energy analysis with a longitudinal homogeneous magnetic field. This way it is possible to measure the energy distribution of low energy electrons (eV-range) in the presence of high energy electrons without distortions by secondary electrons. The functioning and application of the analyzer is demonstrated by measuring the energy distributions of slow electrons emitted by a filament. (orig.) [de

  14. Shake-off processes at the electron transitions in atoms

    International Nuclear Information System (INIS)

    Matveev, V.I.; Parilis, Eh.S.

    1982-01-01

    Elementary processes in multielectron atoms - radiative and Auger transitions, photoionization and ionization by an electron impact etc. are usually followed by the relaxation of electron shells. The conditions under which such multielectron problem could be solved in the shake-off approximation are considered. The shake-off processes occurring. as a result of the electron transitions are described from the general point of view. The common characteristics and peculiar features of this type of excitation in comparison with the electron shake-off under nuclear transformations are pointed out. Several electron shake-off processes are considered, namely: radiative Auger effect, the transition ''two electrons-one photon'', dipole ionization, spectral line broadening, post collision interaction, Auger decay stimulated by collision with fast electrons, three-electron Auger transitions: double and half Auger effect. Their classification is given according to the type of the electron transition causing the shake-off process. The experimental data are presented and the methods of theoretical description are reviewed. Other similar effects, which could follow the transitions in electron shells are pointed out. The deduction of shake-off approximation is presented, and it is pointed out that this approach is analogous to the distorted waves approximation in the theory of scattering. It was shown that in atoms the shake-off approximation is a very effective method, which allows to obtain the probability of different electronic effects

  15. Electron clouds in high energy hadron accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, Fedor

    2013-08-29

    The formation of electron clouds in accelerators operating with positrons and positively charge ions is a well-known problem. Depending on the parameters of the beam the electron cloud manifests itself differently. In this thesis the electron cloud phenomenon is studied for the CERN Super Proton Synchrotron (SPS) and Large Hadron Collider (LHC) conditions, and for the heavy-ion synchrotron SIS-100 as a part of the FAIR complex in Darmstadt, Germany. Under the FAIR conditions the extensive use of slow extraction will be made. After the acceleration the beam will be debunched and continuously extracted to the experimental area. During this process, residual gas electrons can accumulate in the electric field of the beam. If this accumulation is not prevented, then at some point the beam can become unstable. Under the SPS and LHC conditions the beam is always bunched. The accumulation of electron cloud happens due to secondary electron emission. At the time when this thesis was being written the electron cloud was known to limit the maximum intensity of the two machines. During the operation with 25 ns bunch spacing, the electron cloud was causing significant beam quality deterioration. At moderate intensities below the instability threshold the electron cloud was responsible for the bunch energy loss. In the framework of this thesis it was found that the instability thresholds of the coasting beams with similar space charge tune shifts, emittances and energies are identical. First of their kind simulations of the effect of Coulomb collisions on electron cloud density in coasting beams were performed. It was found that for any hadron coasting beam one can choose vacuum conditions that will limit the accumulation of the electron cloud below the instability threshold. We call such conditions the ''good'' vacuum regime. In application to SIS-100 the design pressure 10{sup -12} mbar corresponds to the good vacuum regime. The transition to the bad vacuum

  16. During the countdown towards energy transition

    International Nuclear Information System (INIS)

    Roche, Catherine; Lahorgue, Marie-Beatrice

    2015-01-01

    Placed in the perspective of the passing into law of the energy transition bill - programmed in Parliament for the spring -, news on the legal front has been less intense in 2014 than in the previous year. Most of the texts adopted were modifications of existing texts. A review in detail covering the December 2013-November 2014 period. (authors)

  17. Sustainable Energy Landscape: Implementing Energy Transition in the Physical Realm

    NARCIS (Netherlands)

    Stremke, S.

    2015-01-01

    Since the beginning of the new millennium, the concept of “energy landscape” is being discussed by academia from the environmental design domain while more and more practitioners have been contributing to sustainable energy transition. Yet, there remains some ambiguity as to what exactly is meant

  18. From quantum transitions to electronic motions

    Science.gov (United States)

    Krausz, Ferenc

    2017-01-01

    Laser spectroscopy and chromoscopy permit precision measurement of quantum transitions and captures atomic-scale dynamics, respectively. Frequency- and time-domain metrology ranks among the supreme laser disciplines in fundamental science. For decades, these fields evolved independently, without interaction and synergy between them. This has changed profoundly with controlling the position of the equidistant frequency spikes of a mode-locked laser oscillator. By the self-referencing technique invented by Theodor Hänsch, the comb can be coherently linked to microwaves and used for precision measurements of energy differences between quantum states. The resultant optical frequency synthesis has revolutionized precision spectroscopy. Locking the comb lines to the resonator round-trip frequency by the same approach has given rise to laser pulses with controlled field oscillations. This article reviews, from a personal perspective, how the bridge between frequency- and time-resolved metrology emerged on the turn of the millennium and how synthesized several-cycle laser fields have been instrumental in establishing the basic tools and techniques for attosecond science.

  19. Transition towards energy efficient machine tools

    Energy Technology Data Exchange (ETDEWEB)

    Zein, Andre [Technische Univ. Braunschweig (Germany). Inst. fuer Werkzeugmaschinen und Fertigungstechnik

    2012-07-01

    Provides unique data about industrial trends affecting the energy demand of machine tools. Presents a comprehensive methodology to assess the energy efficiency of machining processes. Contains an integrated management concept to implement energy performance measures into existing industrial systems. Includes an industrial case study with two exemplary applications. Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The target audience primarily comprises researchers and practitioners challenged to enhance energy efficiency in manufacturing. The book may also be beneficial for graduate students who want to specialize in this field.

  20. The role of hydrocarbons in energy transition

    International Nuclear Information System (INIS)

    2015-11-01

    This publication presents some reflections and statements as well as data regarding the role of hydrocarbons in energy production and consumption, in order to better highlight the role hydrocarbons may have in energy transition. It outlines the still very important share of oil in primary and final energy, and more particularly in transports, and that, despite the development of other energies, an energy transition is always very slow. It discusses the perspectives for hydrocarbon reserves and production of oil and natural gas. It outlines that oil remains the most important energy for mobility, the benefits of conventional fuels, and that distribution infrastructures must be preserved and developed. It discusses the evolution of the economic situation of the refining activity (more particularly its margin). It outlines the high contribution of oil industry to economic activity and employment in France, discusses the French energy taxing policy and environmental taxing policy, discusses the issue of security of energy supply (with its different components: exploration-production, refining, logistics and depots, distribution and station network). It discusses the possible role shale hydrocarbons may have in the future. For each issue, the position and opinion of the UFIP (the French Union of oil industries) is stated. The second part of the document proposes a Power Point presentation with several figures and data on these issues

  1. Dispersion self-energy of the electron

    International Nuclear Information System (INIS)

    Hawton, M.

    1991-01-01

    Electron mass renormalization and the Lamb shift have been investigated using the dispersion self-energy formalism. If shifts of both the electromagnetic field and quantum-mechanical transitions frequencies are considered, absorption from the electromagnetic field is canceled by emission due to atomic fluctuations. The frequencies of all modes are obtained from the self-consistency condition that the field seen by the electron is the same as the field produced by the expectation value of current. The radiation present can thus be viewed as arising from emission and subsequent reabsorption by matter. As developed here, the numerical predictions of dispersion theory are identical to those of quantum electrodynamics. The physical picture implied by dispersion theory is discussed in the context of semiclassical theories and quantum electrodynamics

  2. Energy transition in the transport sector

    International Nuclear Information System (INIS)

    Duchemin, Bruno; Genest, Sebastien

    2013-01-01

    Within the European framework, France has committed to a 20% reduction of its GHG emission by 2020 compared with 1990, and reaching the 'factor 4' by 2050. The 2005 POPE Act (the French Energy Policy Guidance Act) makes climate change a priority of the energy policy, setting out a 3% yearly reduction of our country's GHG emissions. This means combining energy efficiency and restraint, as is highlighted by the first chapter of the 'energy transition road-map'. Energy is a major component of transport. Designing its transition requires us to question the very organisation of our society: materials and their usage, the means of transport to favour and the infrastructures to implement, costs for competitiveness, the organisation of work and commuting... At a global scale, needs for mobility are increasing, as is the urgent need to deal with environmental problems. There are huge emerging markets for public transport, increasingly efficient and smart cars, information and transmission networks, infrastructures, the organisation of transport... However, France has all the assets to become a world leader in carbon-free transport. Succeeding in this change means organising the service to meet the needs of all, people, businesses, transport operators and industry, starting this transition right away. Policies must clearly define objectives and the means of achieving them through coordinated actions within a long term approach. The ESEC formulates a set of proposals in this direction

  3. Negawatt / Negatep, the cost of energy transition

    International Nuclear Information System (INIS)

    Acket, Claude; Bacher, Pierre

    2013-01-01

    Within the debate on energy transition, the Negawatt scenario predicts a strong decrease of final consumption and the end of the nuclear, whereas the Negatep scenario predicts a moderate decrease of consumption, more nuclear energy to face the challenges of low-carbon energy. Independently of the technical feasibility and social acceptance of these both opposite scenarios, this study proposes a comparative economic assessment for each expense and saving of these scenarios in different sectors (housing insulation, infrastructure works for transports, renewable heat, non-intermittent and intermittent energy, nuclear energy, biomass-based fuels, and fossil fuels). This comparison is based on two reference evolutions: a status quo (the energy situation remains the same) and 'business as usual' (growth continuity). Negawatt appears to be less expensive, but would imply a socially dangerous deterioration

  4. Energy transition and urban ecological inequalities

    International Nuclear Information System (INIS)

    Hamman, Philippe; Christen, Guillaume

    2017-01-01

    This paper deals with social inequalities in the relationship to the environment, by looking at the capacity of actors to mobilize around renewable energy initiatives in the context of the energy transition. It is based on field surveys (qualitative and quantitative) on an urban scale, conducted between 2012 and 2015 in the metropolitan area of Strasbourg. We show that the emphasis on resident involvement masks the reality of rather prescriptive 'eco-innovations'; and that the differentiated relations of the inhabitants to the technical tools meant to materialize renewable energy reveal ecological inequalities that reinforce socio-economic division in the city

  5. Energy transition? A lever for competitiveness

    International Nuclear Information System (INIS)

    Institut Montaigne

    2013-01-01

    At a time when the 'energy transition' is being hotly debated by the nation, the right energy policy will he based on three pillars: supply private and business consumers at attractive prices; contain the risks associated with excessively high dependence on external sources of supply; finally reduce environmental pollution. Making these fully operative will require that all prices reflect costs at national level and that a full-fledged energy policy be put in place by the European Union over the time frame 2030-2050. (author)

  6. Astrophysical relevance of γ transition energies

    International Nuclear Information System (INIS)

    Rauscher, Thomas

    2008-01-01

    The relevant γ energy range is explicitly identified where additional γ strength must be located to have an impact on astrophysically relevant reactions. It is shown that folding the energy dependences of the transmission coefficients and the level density leads to maximal contributions for γ energies of 2≤E γ ≤4 unless quantum selection rules allow isolated states to contribute. Under this condition, electric dipole transitions dominate. These findings allow us to more accurately judge the relevance of modifications of the γ strength for astrophysics

  7. Energy-urban transition: The Mexican case

    International Nuclear Information System (INIS)

    Paez, Armando

    2010-01-01

    In this paper I present a study regarding the institutional conditions of Mexican cities based on a post-petroleum urban model that considers transport, architecture, urban planning and land use, renewable energy sources, energy saving and efficiency, and urban metabolism issues. The model was constructed with recommendations of authors and organizations that have analysed the energy dimension of cities under an energy-availability, environmental or petroleum-independent view. To make the study I sent a questionnaire to some local governments of all the country. The information indicates that Mexican cities do not have institutional conditions to manage the urban-energy transition that signify the end of cheap oil and the peak of world oil production.

  8. Energy transition. Between reform and revolution

    International Nuclear Information System (INIS)

    Laville, Bettina

    2014-07-01

    The author comments the content of the French bill project on energy transition. She first discusses the meaning of this concept of energy transition which can be perceived as an evolution, a transformation, a progressive change, rather than a revolution. She recalls the original debate between those who wanted to preserve nuclear energy because it does not produce CO 2 emissions, and those who wanted a more radical change of the energy system. In this respect, she outlines and comments the main statements made by the French President on these issues, and indicates the main measures defined in the bill project regarding the reduction of greenhouse gas emission, the increase of the share of renewable energies, a decrease of the share of nuclear in power production, and a reduction of energy consumption. Then, she discusses how this transition is to be financed, proposes an assessment and a discussion of the skills and shortcomings of the bill project. She notably states that the main shortcoming is the lack of strong objectives regarding the reduction of emissions by transports, and the development of inter-modality. She also regrets the disappearance of the regional public service of energy efficiency, the fact that electricity consumption is not capped. Because of that, it's not that sure that the reduction of greenhouse gas emission by a factor 4 in 2050 with respect to 1990 will be reached. In the next parts, the author discusses the issue of the ecologic tax policy, outlines the importance of being exemplary within the perspective of the 2015 Conference on Climate (COP21)

  9. Understanding electron magnetic circular dichroism in a transition potential approach

    Science.gov (United States)

    Barthel, J.; Mayer, J.; Rusz, J.; Ho, P.-L.; Zhong, X. Y.; Lentzen, M.; Dunin-Borkowski, R. E.; Urban, K. W.; Brown, H. G.; Findlay, S. D.; Allen, L. J.

    2018-04-01

    This paper introduces an approach based on transition potentials for inelastic scattering to understand the underlying physics of electron magnetic circular dichroism (EMCD). The transition potentials are sufficiently localized to permit atomic-scale EMCD. Two-beam and three-beam systematic row cases are discussed in detail in terms of transition potentials for conventional transmission electron microscopy, and the basic symmetries which arise in the three-beam case are confirmed experimentally. Atomic-scale EMCD in scanning transmission electron microscopy (STEM), using both a standard STEM probe and vortex beams, is discussed.

  10. Electron Linacs for High Energy Physics

    International Nuclear Information System (INIS)

    Wilson, Perry B.

    2011-01-01

    The purpose of this article is to introduce some of the basic physical principles underlying the operation of electron linear accelerators (electron linacs). Electron linacs have applications ranging from linacs with an energy of a few MeV, such that the electrons are approximately relativistic, to future electron-positron linear colliders having a collision energy in the several-TeV energy range. For the most part, only the main accelerating linac is treated in this article.

  11. Quantum phase transitions of strongly correlated electron systems

    International Nuclear Information System (INIS)

    Imada, Masatoshi

    1998-01-01

    Interacting electrons in solids undergo various quantum phase transitions driven by quantum fluctuations. The quantum transitions take place at zero temperature by changing a parameter to control quantum fluctuations rather than thermal fluctuations. In contrast to classical phase transitions driven by thermal fluctuations, the quantum transitions have many different features where quantum dynamics introduces a source of intrinsic fluctuations tightly connected with spatial correlations and they have been a subject of recent intensive studies as we see below. Interacting electron systems cannot be fully understood without deep analyses of the quantum phase transitions themselves, because they are widely seen and play essential roles in many phenomena. Typical and important examples of the quantum phase transitions include metal-insulator transitions, (2, 3, 4, 5, 6, 7, 8, 9) metal-superconductor transitions, superconductor-insulator transitions, magnetic transitions to antiferromagnetic or ferromagnetic phases in metals as well as in Mott insulators, and charge ordering transitions. Here, we focus on three different types of transitions

  12. RTE, network for the energy transition

    International Nuclear Information System (INIS)

    Maillard, D.

    2013-01-01

    Energy transition is currently the subject of a wide-ranging national debate. Whatever the options that are retained, one thing is certain: the electricity system in France and in Europe will be confronted with profound changes. As of now, the main vectors for the development of electricity distribution, in France and in Europe, are the indispensable solidarity among territories and the rising flows of electricity from renewable sources. (author)

  13. Which territorial governance for energy transition?

    International Nuclear Information System (INIS)

    Richard, Marion; Berthier, Julien; Delcroix, Julie; Boucher, James; Lenoir, Didier; Cheron, Marie; Sivardiere, Jean; Connor, Helene; Denizot, Damien; Guilhem, Isaac-Georges

    2013-01-01

    The first part of this report proposes an overview of the present situation for climate-energy policies in France. It outlines the lack of transversality of local climate-energy policies which tend to be rather sector-oriented, the lack of coherence of these policies, their lack of efficiency due to a weak power of decision of local communities and to their lack of financial means, and the fact that the territorial organisation is not well adapted to climate-energy stakes. The second part presents and comments a set of proposals: to strengthen the region and the inter-communal levels, to give to local communities political and legal means of action, to reinforce human and financial means dedicated to energy transition, and to strengthen survey, follow-up and assessment missions

  14. Energy transition: gas asserts its assets

    International Nuclear Information System (INIS)

    Passebon, Philippe; Lesquel, Emmanuelle; Leroux, Hugo

    2016-01-01

    Even though it is a fossil energy, gas has a role to play in energy transition as it emits less CO 2 than oil or coal. In this context, it can be used to fill the gaps due to intermittency of some renewable energies, and moreover can also be obtained from organic matter, and then becomes also a renewable source. A set of articles addresses and illustrates these different issues: the development of technologies to exploit methane, the role of substitute for gas, the assets of methane, of natural gas and of biogas, the transformation of electricity into gas in order to easily store energy (notably in the network gas according to the power-to-gas principle), the development of biomass-based methane, the replacement of oil by LNG (liquefied natural gas) in industry and transports (road and sea transport notably)

  15. Number of outer electrons as descriptor for adsorption processes on transition metals and their oxides

    DEFF Research Database (Denmark)

    Calle-Vallejo, Federico; Inoglu, Nilay G.; Su, Hai-Yan

    2013-01-01

    The trends in adsorption energies of the intermediates of the oxygen reduction and evolution reactions on transition metals and their oxides are smoothly captured by the number of outer electrons. This unique descriptor permits the construction of predictive adsorption-energy grids and explains t...

  16. Electron-nuclear. gamma. transition spectrum of a nucleus in a multicharged atomic ion

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, L N; Letokhov, V S

    1987-08-01

    The nuclear emission of absorption spectrum of an atom possesses a set of electron satelites which are due to an alternation of the state of the electron shell. It is shown that the mechanism of formation of the satellites might be different for neutral atoms and high-charge ions. In the first case (loose electron shell) a ''shaking'' of the shell resulting from the interaction between the nucleus and ..gamma.. quantum is predominant. In the second case (rigid electron shell) the mechanism involves a direct interaction between the ..gamma.. quantum and electrons. The second mechanism is important in the case of dipole nuclear transitions and dominates at ..gamma.. quantum energies electron transition multiplicity do not pertain to the second mechanism. Consequently, the satellite spectrum is much enriched and transitions between the fine and hyperfine structure components, transitions and transitions which do not involve a change in the electron configuration can be considered. The relative intensities of the satellites are determined by the smallest parameter ..mu../sub p//sup 2lambda/ (lambda is the nuclear transition multipole order, ..mu../sub p/ approx. 12 ..pi.. is the relative proton mass and z the core mass). In the spectrum of the plasma source the electron satellites corresponding to the ..gamma.. quantum emission and absorption lines are not overlapped by the Doppler contour of the ..gamma.. line.

  17. Power Electronics, Energy Harvesting and Renewable Energies Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The research in the Power Electronics, Energy Harvesting and Renewable Energies Laboratory (PEHREL) is mainly focused on investigation, modeling, simulation, design,...

  18. Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites.

    Science.gov (United States)

    Lee, J H; Choi, Woo Seok; Jeen, H; Lee, H-J; Seo, J H; Nam, J; Yeom, M S; Lee, H N

    2017-11-22

    The topotactic phase transition in SrCoO x (x = 2.5-3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO 2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO 3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO 2.5 , however, it has been conjectured that the magnetic transition is decoupled to the electronic phase transition, i.e., the AFM-to-FM transition occurs before the insulator-to-metal transition (IMT), which is still controversial. Here, we bridge the gap between the two-phase transitions by density-functional theory calculations combined with optical spectroscopy. We confirm that the IMT actually occurs concomitantly with the FM transition near the oxygen content x = 2.75. Strong charge-spin coupling drives the concurrent IMT and AFM-to-FM transition, which fosters the near room-T magnetic transition characteristic. Ultimately, our study demonstrates that SrCoO x is an intriguingly rare candidate for inducing coupled magnetic and electronic transition via fast and reversible redox reactions.

  19. Longitudinal Electron Bunch Diagnostics Using Coherent Transition Radiation

    CERN Document Server

    Mihalcea, Daniel; Happek, Uwe; Regis-Guy Piot, Philippe

    2005-01-01

    The longitudinal charge distribution of electron bunches in the Fermilab A0 photo-injector was determined by using the coherent transition radiation produced by electrons passing through a thin metallic foil. The auto-correlation of the transition radiation signal was measured with a Michelson type interferometer. The response function of the interferometer was determined from measured and simulated power spectra for low electron bunch charge and maximum longitudinal compression. Kramers-Kroning technique was used to determine longitudinal charge distribution. Measurements were performed for electron bunch lengths in the range from 0.3 to 2 ps (rms).

  20. Hydrogen collisions with transition metal surfaces: Universal electronically nonadiabatic adsorption

    Science.gov (United States)

    Dorenkamp, Yvonne; Jiang, Hongyan; Köckert, Hansjochen; Hertl, Nils; Kammler, Marvin; Janke, Svenja M.; Kandratsenka, Alexander; Wodtke, Alec M.; Bünermann, Oliver

    2018-01-01

    Inelastic scattering of H and D atoms from the (111) surfaces of six fcc transition metals (Au, Pt, Ag, Pd, Cu, and Ni) was investigated, and in each case, excitation of electron-hole pairs dominates the inelasticity. The results are very similar for all six metals. Differences in the average kinetic energy losses between metals can mainly be attributed to different efficiencies in the coupling to phonons due to the different masses of the metal atoms. The experimental observations can be reproduced by molecular dynamics simulations based on full-dimensional potential energy surfaces and including electronic excitations by using electronic friction in the local density friction approximation. The determining factors for the energy loss are the electron density at the surface, which is similar for all six metals, and the mass ratio between the impinging atoms and the surface atoms. Details of the electronic structure of the metal do not play a significant role. The experimentally validated simulations are used to explore sticking over a wide range of incidence conditions. We find that the sticking probability increases for H and D collisions near normal incidence—consistent with a previously reported penetration-resurfacing mechanism. The sticking probability for H or D on any of these metals may be represented as a simple function of the incidence energy, Ein, metal atom mass, M, and incidence angle, 𝜗i n. S =(S0+a ṡEi n+b ṡM ) *(1 -h (𝜗i n-c ) (1 -cos(𝜗 i n-c ) d ṡh (Ei n-e ) (Ei n-e ) ) ) , where h is the Heaviside step function and for H, S0 = 1.081, a = -0.125 eV-1, b =-8.40 ṡ1 0-4 u-1, c = 28.88°, d = 1.166 eV-1, and e = 0.442 eV; whereas for D, S0 = 1.120, a = -0.124 eV-1, b =-1.20 ṡ1 0-3 u-1, c = 28.62°, d = 1.196 eV-1, and e = 0.474 eV.

  1. The geopolitical challenges of energy transition

    International Nuclear Information System (INIS)

    Lafargue, Francois

    2013-01-01

    As China became in 2010 the first energy consumer in the world, the author gives an overview of the development of energy demand and of nuclear plants in China and in India, and evokes their situation with respect to international nuclear treaties and to their relationship with international bodies. The author then evokes the evolution in the USA where the exploitation of shale gases could result in a drastic reduction of their energetic dependence, but with a negative impact on the environment. Europe is more restrictive on this issue whereas China could also develop this sector. The action of China in the oil sector is also evoked. The author comments the general but slow evolution towards an energy transition with an increase of production of renewable energies, and then the new geographical context of energy production due to these evolutions of energy sources and productions. In a last part, the author gives a rather pessimistic vision as he thinks that an energy crisis is probably to occur

  2. Measurement of peripheral electron temperature by electron cyclotron emission during the H-mode transition in JFT-2M tokamak

    International Nuclear Information System (INIS)

    Hoshino, Katsumichi; Yamamoto, Takumi; Kawashima, Hisato

    1987-01-01

    Time evolution and profile of peripheral electron temperature during the H-mode like transition in a tokamak plasma is measured using the second and third harmonic of electron cyclotron emission (ECE). The so called ''H-mode'' state which has good particle/energy confinement is characterized by sudden decrease in the spectral line intensity of deuterium molecule. Such a sudden decrease in the line intensity of D α with good energy confinement is found not only in divertor discharges, but also in limiter dischargs in JFT-2M tokamak. It is found by the measurement of ECE that the peripheral electron temperature suddenly increases in both of such phases. The relation between H-transition and the peripheral electron temperature or its profile is investigated. (author)

  3. High-energy electron diffraction and microscopy

    CERN Document Server

    Peng, L M; Whelan, M J

    2011-01-01

    This book provides a comprehensive introduction to high energy electron diffraction and elastic and inelastic scattering of high energy electrons, with particular emphasis on applications to modern electron microscopy. Starting from a survey of fundamental phenomena, the authors introduce the most important concepts underlying modern understanding of high energy electron diffraction. Dynamical diffraction in transmission (THEED) and reflection (RHEED) geometries is treated using ageneral matrix theory, where computer programs and worked examples are provided to illustrate the concepts and to f

  4. Electron heating mode transition induced by mixing radio frequency and ultrahigh frequency dual frequency powers in capacitive discharges

    International Nuclear Information System (INIS)

    Sahu, B. B.; Han, Jeon G.

    2016-01-01

    Electron heating mode transitions induced by mixing the low- and high-frequency power in dual-frequency nitrogen discharges at 400 mTorr pressure are presented. As the low-frequency (13.56 MHz) power decreases and high-frequency (320 MHz) power increases for the fixed power of 200 W, there is a transition of electron energy distribution function (EEDF) from Druyvesteyn to bi-Maxwellian type characterized by a distinguished warm electron population. It is shown that this EEDF evolution is attributed to the transition from collisional to collisionless stochastic heating of the low-energy electrons.

  5. Power electronics for renewable energy systems

    DEFF Research Database (Denmark)

    Iov, Florin; Blaabjerg, Frede

    2009-01-01

    sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss some of the most emerging renewable energy sources......, wind energy and photovoltaics, which by means of power electronics are changing from being minor energy sources to be acting as important power sources in the energy system....

  6. Ultrafast optical snapshots of hybrid perovskites reveal the origin of multiband electronic transitions

    Science.gov (United States)

    Appavoo, Kannatassen; Nie, Wanyi; Blancon, Jean-Christophe; Even, Jacky; Mohite, Aditya D.; Sfeir, Matthew Y.

    2017-11-01

    Connecting the complex electronic excitations of hybrid perovskites to their intricate organic-inorganic lattice structure has critical implications for energy conversion and optoelectronic technologies. Here we detail the multiband, multivalley electronic structure of a halide hybrid perovskite by measuring the absorption transients of a millimeter-scale-grain thin film as it undergoes a thermally controlled reversible tetragonal-to-orthogonal phase transition. Probing nearly single grains of this hybrid perovskite, we observe an unreported energy splitting (degeneracy lifting) of the high-energy 2.6 eV band in the tetragonal phase that further splits as the rotational degrees of freedom of the disordered C H3N H3 + molecules are reduced when the sample is cooled. This energy splitting drastically increases during an extended phase-transition coexistence region that persists from 160 to 120 K, becoming more pronounced in the orthorhombic phase. By tracking the temperature-dependent optical transition energies and using symmetry analysis that describes the evolution of electronic states from the tetragonal phase to the orthorhombic phase, we assign this energy splitting to the nearly degenerate transitions in the tetragonal phase from both the R - and M -point-derived states. Importantly, these assignments explain how momentum conservation effects lead to long hot-carrier lifetimes in the room-temperature tetragonal phase, with faster hot-carrier relaxation when the hybrid perovskite structurally transitions to the orthorhombic phase due to enhanced scattering at the Γ point.

  7. Clean energy for Europe in transition

    International Nuclear Information System (INIS)

    Zaleski, C.P.

    1992-01-01

    Energy, an important subject, cannot be validly discussed alone. For some time already, most experts agree that is necessary to include the environmental effects if one seeks a valid discussion. It appears now this was especially pointed out by the dramatic changes in Russia and other Eastern and Central European countries that the only efficient way to discuss energy is even more global. That discussion should, of course, include economics and the politico-economic system, but also society-people's motivations, mentality, education and finally a touch of philosophy, notably value systems. The debates of the third MIEC conference were characterized by their interdisciplinary character. The organizers tried to address these different issues by having them discussed together while emphasizing in different sessions specific aspects like economics and political system society, education, and value system and finally scientific and technical aspects of new energy technology. This meeting presents 28 papers of which 15 are in the INIS and Energy database scope. In the first and the second issue, the subject studied is energy policy in transition economy. The third issue describes the relationships between energy, environment and society. In the two last issues, the problems of safety in nuclear industry are studied

  8. Nuclear fission fragment excitation of electronic transition laser media

    International Nuclear Information System (INIS)

    Lorents, D.C.; McCusker, M.V.; Rhodes, C.K.

    1976-01-01

    The properties of high energy electronic transition lasers excited by fission fragments are expanded. Specific characteristics of the media including density, excitation rates, wavelength, kinetics, fissile material, scale size, and medium uniformity are assessed. The use of epithermal neutrons, homogeneously mixed fissile material, and special high cross section nuclear isotopes to optimize coupling of the energy to the medium are shown to be important considerations maximizing the scale size, energy deposition, and medium uniformity. A performance limit point of approximately 1000 J/l in approximately 100 μs pulses is established for a large class of systems operating in the near ultraviolet and visible spectral regions. It is demonstrated that e-beam excitation can be used to simulate nuclear pumping conditions to facilitate the search for candidate media. Experimental data for the kinetics of a XeF* laser operating in Ar/Xe/F 2 /UF 6 mixtures are given. These reactor-pumped systems are suitable for scaling to volumes on the order of (meters) 3

  9. Accelerating the transition to sustainable energy systems

    International Nuclear Information System (INIS)

    Jefferson, Michael

    2008-01-01

    The slow pace of transition to sustainable energy systems is the result of several factors running in parallel. The starting points are very low. Even 30% per annum increases in rated capacity (for wind energy or solar PV, for example) take many years to make a big impact at the global level. Policy initiatives are for the most part ineffectual in relation to the urgency and scale of what is required, and often fail to address the fundamental causes of this slow progress. This reflects a 'top-down' approach-often accompanied by unrealistic targets and simultaneously undermined by a lack of consistency across policies, which reflect a 'utopian social engineering mentality', made worse because: 'The Planner's response to failure of previous interventions (is) to do more intensive and comprehensive interventions' as William Easterly has put it. In short, there is little or no accountability. This approach has failed to harness the sympathy, imagination, self-interest, or sound options of energy users-although it may attract developers, including those not hitherto noted for renewable energy projects or environmental concern. Targets are usually too short term and clearly unrealistic, especially where fossil fuel use is rising very rapidly, and renewable energy use expands modestly. Government subsidies for traditional energy forms continue. Insufficient attention is paid to what individuals might achieve in energy efficiency and renewable energy terms if permitted to have, or retain (in industrialized countries, where the burden of taxation is often inhibiting), the wherewithal to make the necessary investments. Subsidy systems often promote renewable energy schemes that are misdirected and buoyed up by grossly exaggerated claims. One or two mature renewable energy technologies are pushed nationally with insufficient regard for their costs, contribution to electricity generation, transportation fuels' needs, or carbon emission avoidance. Investors are rewarded

  10. Transition to H-mode by energetic electrons

    International Nuclear Information System (INIS)

    Itoh, Kimitaka; Itoh, Sanae.

    1992-07-01

    Effect of the electron loss due to the toroidal ripple on an H-mode transition is studied. When energetic electrons exist in tokamaks, e.g., in the case of the current drive by lower hybrid (LH) waves, the edge electric field can show the bifurcation to the more positive value. In this state, both the electron loss and ion loss (such as loss cone loss) are reduced. The criterion for the transition is derived. Comparison with H-mode in JT-60 LH plasma shows a qualitative agreement. (author)

  11. Transition without Conflict? Renewable Energy Initiatives in the Dutch Energy Transition

    Directory of Open Access Journals (Sweden)

    Antonia Proka

    2018-05-01

    Full Text Available In the context of the slowly progressing energy transition, a number of renewable energy initiatives have been emerging in the Netherlands. These initiatives represent alternatives to the dominant functioning of the energy system, and as such, may come into conflict with it. Transitions involve system destabilisation and conflict between the incumbent regime and the initiatives originating in niches. In order to assess the transformative potential of such initiatives, this paper addresses the question: what kind of conflicts and tensions arise from renewable energy initiatives, and what strategies do they develop to overcome or avoid them? Combined with a business model perspective, transition thinking enabled a better understanding of how the initiatives organise themselves, and where the points of friction with their institutional context emerge. We suggest that the instances of conflict may function as an indication for the state of the energy transition and the transformative potential impact of such initiatives. The instances discussed in this contribution relate to existing support schemes, technology choices, and the overall organisational networks of the emerging sector.

  12. Electronic and thermodynamic properties of the transition between metallic and nonmetallic states in dense media

    International Nuclear Information System (INIS)

    Fortin, Xavier

    1971-01-01

    The effects of thermal excitation are introduced in the study of a simple electronic structure model for condensed media. The choice of a particle-interaction potential leads to a self-consistent calculation performed on a computer. This calculation gives a metal - nonmetal transition similar to the MOTT transition. We consider the effects of temperature and density variations upon this transition. It is possible to make use of this electronic structure to obtain the thermodynamic properties near the transition: pressure, free energy, sound velocity. The numerical results of this simple model are satisfactory. Particularly, if a dielectric constant is taken into account, the transition temperature and density are of the same order of magnitude as those observed experimentally in semiconductors. (author) [fr

  13. Electronic structure of f1 actinide complexes. Pt. 3. Quasi-relativistic density functional calculations of the optical transition energies of PaX62-(X=F,Cl,Br,I)

    International Nuclear Information System (INIS)

    Kaltsoyannis, N.

    1998-01-01

    For pt.II see J. Organomet. Chem., vol.528, p.19, 1997. The four f→f transition energies of the single 5f-based electron of PaX 6 2- (X=F, Cl, Br, I) have been calculated using quasi-relativistic local density functional theory. Excellent agreement ( -1 ) between theory and experiment is obtained for PaCl 6 2- , PaBr 6 2- and PaI 6 2- by variation of the value of α in the Xα exchange-only functional. In contrast, more sophisticated calculational methods including non-local corrections fail to reproduce the experiments well. The PaF 6 2- results are less impressive (up to 1000 cm -1 discrepancy), possibly due to non-aufbau orbital occupations for certain values of α. The values of α employed lie in the range 0.79-0.85, somewhat higher than the most widely used value of 0.7. The theoretical basis for using such values is discussed. (orig.)

  14. Precision measurements of high-energy conversion electron lines and determination of neutron binding energies

    International Nuclear Information System (INIS)

    Braumandl, F.

    1979-01-01

    The paper first discusses the energy accuracy of the BILL conversion electron spectrometer at the Grenoble high flux reactor. With an improved temperature stabilisation of the magnets, an energy accuracy of ΔE/E -5 can be reached. After this, highly exact measurements of high-energy conversion electron lines of the 200 Hg, 114 Cd, 165 Dy, 168 Er, 239 U nuclei and the 13 C, 28 Al 3 H and 92 Zr photoelectron lines were carried out. Energy calibration of the spectrometer was carried out in the 1.5 MeV to 6.5 MeV range with intensive high-energy transitions of the 200 Hg nucleus. Systematic calibration errors could be investigated by means of combinations between the calibration lines. A calibration for absolute energies was obtained by comparing low-energy gamma transitions of 200 Hg with the 411.8 keV gold standard. (orig.) [de

  15. Research for the energy transition. The organization of the energy systems

    International Nuclear Information System (INIS)

    2017-01-01

    The volume on research for the energy transition includes contributions to the FVEE annual meeting 2016 concerning the following issues: status and perspectives of the energy transition, key technologies for the energy transition, political boundary conditions, development trends in photovoltaics, components for the energy supply (wind energy, hydrogen technologies, smart bioenergy concept, contribution of the geosphere), grids and storage systems for the energy transition, research network renewable energies.

  16. Recommended Auger-electron kinetic energies for 42 elemental solids

    International Nuclear Information System (INIS)

    Powell, C.J.

    2010-01-01

    An analysis is presented of Auger-electron kinetic energies (KEs) from four data sources for 65 Auger transitions in 45 elemental solids. For each data source, a single instrument had been used to measure KEs for many elements. In order to compare KEs from two sources, it was necessary to recalibrate the energy scales of each instrument using recommended reference data. Mean KEs are given for most of the Auger transitions for which there were at least two independent measurements and for which differences from the mean KEs were considered acceptably small. In several cases, comparisons were made to published KE data to resolve discrepancies. We are able to recommend mean KEs for 59 Auger transitions from 42 elemental solids and to provide estimates of the uncertainties of these KEs. This compilation should be useful for the determination of chemical shifts of Auger peaks in Auger electron spectroscopy and X-ray photoelectron spectroscopy.

  17. Angular distribution of scattered electron and medium energy electron spectroscopy for metals

    International Nuclear Information System (INIS)

    Oguri, Takeo; Ishioka, Hisamichi; Fukuda, Hisashi; Irako, Mitsuhiro

    1986-01-01

    The angular distribution (AD) of scattered electrons produced by medium energy incident electrons (E P = 50 ∼ 300 eV) from polycrystalline Ti, Fe, Ni, Cu and Au were obtained by the angle-resolved medium energy electron spectrometer. The AD of the energy loss peaks are similar figures to AD of the elastically reflected electron peaks. Therefore, the exchanged electrons produced by the knock-on collision between the incident electrons and those of metals without momentum transfer are observed as the energy loss spectra (ELS). This interpretation differs from the inconsequent interpretation by the dielectric theory or the interband transition. The information depth and penetration length are obtained from AD of the Auger electron peaks. The contribution of the surface to spectra is 3 % at the maximum for E P = 50 eV. The true secondary peaks representing the secondary electron emission spectroscopy (SES) are caused by the emissions of the energetic electrons (kT e ≥ 4 eV), and SES is the inversion of ELS. The established fundamental view is that the medium energy electron spectra represent the total bulk density of states. (author)

  18. A Less Ambitious Energy Transition for Germany

    International Nuclear Information System (INIS)

    Beeker, Etienne; Yahiel, Michel; Lenglart, Fabrice; Broca, Olivier de; Senne, Valerie

    2017-08-01

    In the wake of the 2011 Fukushima nuclear disaster, the German authorities launched the country's energy transition, or Energiewende. With near unanimous support of Germany's citizens, it was seen as a society-wide project. The enthusiasm the Energiewende generated soon spread beyond the Rhine. Indeed, for many French people it became the model to follow. Replacing nuclear energy and fossil fuels with renewable energy sources that were local when possible, developing electric mobility and making progress towards a zero carbon economy were all virtuous goals. What's more, it seemed they could be attained over a relatively short period of time and at reasonable cost. Today, the Energiewende's future looks less bright. While Germany produces a third of its electricity from renewable energy, this comes at a high price. The cost of electricity for small consumers more than doubled between 2000 and 2013. At the same time, the country continues to rely on coal to produce a large share of its electricity and still has one of the highest levels of CO_2 per person in Europe. But Germany's population is divided about closing its coal-fired and lignite power plants, not to mention doing so would jeopardize its energy supply. Add to this the fact the massive development of intermittent renewable energy sources has made the German power grid unstable and has necessitated the construction of thousands of kilometers of high voltage lines amidst strong local opposition. Lastly, electrifying the transport sector could serve to compound the series of scandals that have hit the automotive industry. Against this backdrop, the coalition government formed following the September 2017 federal elections could very well lower the bar for the Energiewende. (author)

  19. 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.

  20. Innovation policy for the Dutch energy transition Operationalising transition management?

    NARCIS (Netherlands)

    D.A. Loorbach (Derk); R. Kemp (René)

    2005-01-01

    textabstractThe term transition is a key term of the fourth national environmental policy plan (NMP4, 2001), which put forward transition management (Rotmans et al, 2000) as a new policy approach for dealing with persistent and highly complex societal problems such as climate change, loss of

  1. Transition? What transition? : Changing energy systems in an increasingly carbon constrained world

    NARCIS (Netherlands)

    Mc Cahery, J.A.; Lopez de Silanes, Florencio; de Roode, Alexander

    2014-01-01

    Energy transitions have been taking place continuously since the Industrial Revolution. These transitions primarily involve national energy mixes. In general, countries keep moving up the energy ladder, meaning that they integrate larger and larger proportions of specialized fuels into their energy

  2. Is the German energy transition sustainable?

    International Nuclear Information System (INIS)

    Beeker, Etienne; Godot, Clelia

    2012-09-01

    In 2011, Germany began a radical energy policy, or 'Energiewende', with the aim of completely abandoning nuclear power by 2022 and then achieving an 80-95% reduction in the country's greenhouse gas emissions by 2050. By this date, the country will therefore have to be producing its electricity almost completely without the use of gas, oil and coal, having replaced 80% of these sources with renewable energies. Germany is a rich country with one of the most competitive industries in the world. Its environmental commitments have been clearly stated and Energiewende, which is widely discussed throughout the country, has so far seen strong support from the population, despite the expected increases in the price of electricity which, however, is already almost twice as expensive as in France. Germany therefore seems to hold the winning cards required to successfully implement its energy transition. However, many difficulties need to be overcome if this energy policy is to succeed, such as the development of the national power grid, the cost and financing of the necessary investments, improved electricity storage techniques, the acceptability of the planned increases in the price of electricity or the financial difficulties experienced by solar panel manufacturers as a result of the sharp reduction in subsidies and competition from Asia. In addition, recent political dissent within the government regarding the measures implemented to achieve its stated goal has slowed down the federal decision-making process on this matter. Finally, Germany's decision is not without consequences for its European neighbours. It is upsetting and weakening the supply and demand balance of the European energy system and putting some operators in a difficult position. The eyes of all energy world observers are therefore riveted on the changes taking place in Germany, because they will have significant consequences for the entire European Union, and even beyond. Contents: - The ambitious goal

  3. Energy transition in transport sector from energy substitution perspective

    Science.gov (United States)

    Sun, Wangmin; Yang, Xiaoguang; Han, Song; Sun, Xiaoyang

    2017-10-01

    Power and heating generation sector and transport sector contribute a highest GHG emissions and even air pollutions. This paper seeks to investigate life cycle costs and emissions in both the power sector and transport sector, and evaluate the cost-emission efficient (costs for one unit GHG emissions) of the substitution between new energy vehicles and conventional gasoline based vehicles under two electricity mix scenarios. In power sector, wind power and PV power will be cost comparative in 2030 forecasted with learning curve method. With high subsidies, new energy cars could be comparative now, but it still has high costs to lower GHG emissions. When the government subsidy policy is reversible, the emission reduction cost for new energy vehicle consumer will be 900/ton. According to the sensitive analysis, the paper suggests that the government implement policies that allocate the cost to the whole life cycle of energy production and consumption related to transport sector energy transition and policies that are in favor of new energy vehicle consumers but not the new energy car producers.

  4. Carbon pricing. A lever for energy transition

    International Nuclear Information System (INIS)

    2016-01-01

    The international community has set itself the target of limiting the global temperature rise to 2 deg. C. In today's world, the challenge is to invent new ways of manufacturing goods, producing food, travelling and keeping ourselves warm, without emitting more greenhouse gases (GHG) into the atmosphere than what we are technically able to remove from it. Climate action can be considered as an insurance for our societies against unacceptable costs generated by the risk of increasingly frequent climate-triggered natural disasters, irreversible damage to ecosystems and mass population migrations. In addition to avoid climate damage there are many benefits of climate action, including greater energy autonomy, reduced atmospheric pollution, which is harmful for human health, and the economic benefits of new green growth sectors. However, the efforts needed to make the transition to economies that emit fewer greenhouse gases must not be underestimated. This transition requires the mass redirection of investments into clean transport, renewable energy sources, building insulation and the development of agro-ecology, in a highly restricted financial and budgetary context. The economic and financial tools used for explicit or implicit carbon pricing give clear messages about the benefits of emitting less carbon, or alternatively the cost of greenhouse gas emissions for society. Consequently, they make it possible to accelerate the energy transition. 74 countries and over 1,000 businesses formed a coalition for carbon pricing during the United Nations Climate Summit in September 2014, held at the invitation of the UN Secretary-General. The goal of the coalition is to promote productive dialogue between public and private decision-makers concerning opportunities to extend carbon pricing policies. It has been officially launched on November 30, 2015, on the opening day of COP21. It has been officially launched on November 30, 2015, on the opening day of COP21. Members of the

  5. The challenges of energy markets in transition

    International Nuclear Information System (INIS)

    Dumas, D.

    1999-01-01

    The transition period includes the processes as follows: liberalization, deregulation, privatization and restructuring. Liberalization consists of multiple changes: 1. Ownership - from public to private; 2. Industry structure - from vertically integrated to unbundled; 3. Market competition - from monopoly to competitive; 4. Product-mix - from single to multi-products; 5. Market approach - from service to product (wholesale); 6. System management - from self-managed to decentralized; 7. Planning horizon - from long to short term and 8. Participants - from national to trans-national. The energy sector is to ensure a reliable, long-term supply of energy in sufficient quantities at affordable prices from processes that are compatible with prudent environmental standards. The evolutionary model of an energy utility foresees a transition from traditional utility (integrated monopoly utility) through local wholesale trading and partial competition (competition for large customers) to competition for all customers and to redefined utilities (bundling multi-product services). Substantial liberalization of electricity have taken place as follows: in 6 countries in Western Europe and 12 plan to do it; in 4 countries in Eastern Europe and 8 - plan to do it; in 2 countries in Asia and Australasia and 12 plan to do it; in 4 countries in South America and 3 plan to do it. There is no liberalization of electricity in Central and North America till now but 6 in Central and 3 in North America plan to do it in future. Substantial liberalization of downstream gas have taken place: only in one country in Western Europe but 6 plan to do it in future; also in one country in Asia and Australasia and 3 plan to do it; in one country in South America and 2 plan to do it and in two countries in North America and only one plan to do it in future. The goals of liberalization include: reducing the cost of energy; improving economic efficiency; attracting capitals and paying off government debt

  6. Energy transition. Who will board the energy Airbus?

    International Nuclear Information System (INIS)

    Moragues, Manuel

    2014-01-01

    As the French President called for the creation of a French-German company dedicated to energy transition, inspired by the Airbus project which emerged to share the design and development costs of a specific product (a large capacity aircraft), this article comments the possibility of applying such a strategy between the main French and German actors like Siemens, RWE, Alstom, EDF. Such an idea has already its reality as some French and German are cooperating in different projects: offshore wind energy consortium, research and development in photovoltaic, smart grids, energy storage, and so on. Some of these projects are evoked and commented, for example one which has emerged just after the President's speech: the project of a giant factory of solar arrays proposed by the CEA and the Fraunhofer Institute. One major need is also evoked, the harmonization at the regulation stage

  7. Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

    International Nuclear Information System (INIS)

    Seletskiy, Sergey M.; Rochester U.

    2005-01-01

    Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the first cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cooling. The Recycler Electron Cooler (REC) is the key component of the Tevatron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV carrying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 (micro)rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible. Chapter 1 is an introduction where I describe briefly the theory and the history of electron cooling, and derive the requirements to the quality of electron beam and requirements to the basic parameters of the Recycler Electron Cooler. Chapter 2 is devoted to the theoretical consideration of the motion of electrons in the cooling section, description of the cooling section and of the measurement of the magnetic fields. In Chapter 3 I consider different factors that increase the effective electron angle in the cooling section and suggest certain algorithms for the suppression of parasitic angles. Chapter 4 is devoted to the measurements of the energy of the electron beam. In the concluding Chapter 5 I review

  8. Power Electronics for Renewable Energy Systems

    DEFF Research Database (Denmark)

    Choi, U. M.; Lee, K. B.; Blaabjerg, Frede

    2012-01-01

    The use of renewable energy sources are increased because of the depletion of natural resources and the increasing pollution level from energy production. The wind energy and the solar energy are most widely used among the renewable energy sources. Power electronics is needed in almost all kinds...... of renewable energy system. It controls the renewable source and interfaces with the load effectively, which can be grid-connected or van work in stand-alone mode. In this presentation, overview of wind and photovoltaic energy systems are introduced. Next, the power electronic circuits behind the most common...

  9. On some practical consideration of the electron beam breakup transit time oscillator

    International Nuclear Information System (INIS)

    Kwan, T.J.T.

    1992-01-01

    The electron beam breakup transit time oscillator (BTO) makes use of the interaction between an electron beam and the azimuthally azimuthally asymmetric transverse magnetic mode (TM 110 ) of a cavity to facilitate the exchange of energy between them. Linear theory has shown a large growth rate in the regime where space-charge effects can be ignored. In this study, we have investigated the non-ideal elements in the BTO and evaluated their effects accordingly. The practical issues under consideration are electron beam quality, energy, and space-charge potential. Our calculations indicate only a modest unfavorable scalings with respect to these parameters

  10. Mixed ion beams near transition energy

    International Nuclear Information System (INIS)

    Hancock, S.

    1991-01-01

    The standard derivations of the energy and phase of the synchronous particle in a proton accelerator assume, as if by definition, that said synchronous particle lies on the central orbit of the machine. This is manifestly unjustified in the particular case of the acceleration near transition of a mixture of ions, when a small difference in charge-to-mass ratio can produce a large radial separation of the different ion species. The development of a simple derivation of the parameters of the synchronous particle that involves no such a priori constraint has yielded some surprises; not, least, a belated explanation for an apparent anomaly encountered in 1987, when a mixture of oxygen and sulphur ions was accelerated in the CERN Proton Synchrotron for the first time. These ideas are supported by measurements performed in 1990 during a second ion run

  11. Sheath structure transition controlled by secondary electron emission

    Science.gov (United States)

    Schweigert, I. V.; Langendorf, S. J.; Walker, M. L. R.; Keidar, M.

    2015-04-01

    In particle-in-cell Monte Carlo collision (PIC MCC) simulations and in an experiment we study sheath formation over an emissive floating Al2O3 plate in a direct current discharge plasma at argon gas pressure 10-4 Torr. The discharge glow is maintained by the beam electrons emitted from a negatively biased hot cathode. We observe three types of sheaths near the floating emissive plate and the transition between them is driven by changing the negative bias. The Debye sheath appears at lower voltages, when secondary electron emission is negligible. With increasing applied voltage, secondary electron emission switches on and a first transition to a new sheath type, beam electron emission (BEE), takes place. For the first time we find this specific regime of sheath operation near the floating emissive surface. In this regime, the potential drop over the plate sheath is about four times larger than the temperature of plasma electrons. The virtual cathode appears near the emissive plate and its modification helps to maintain the BEE regime within some voltage range. Further increase of the applied voltage U initiates the second smooth transition to the plasma electron emission sheath regime and the ratio Δφs/Te tends to unity with increasing U. The oscillatory behavior of the emissive sheath is analyzed in PIC MCC simulations. A plasmoid of slow electrons is formed near the plate and transported to the bulk plasma periodically with a frequency of about 25 kHz.

  12. Energy sector reform, energy transitions and the poor in Africa

    International Nuclear Information System (INIS)

    Prasad, Gisela

    2008-01-01

    There is little systematic information about the impact of energy sector reform on all sources and methods of energy utilised or potentially utilised by the poor. It is not sufficiently known what fuels the poor use, if a larger range of fuels becomes available and affordable and if barriers to access and consumption are reduced. A detailed assessment is presented for four countries, three in Africa (Botswana, Ghana and Senegal) and for comparison one in Latin America (Honduras), of steps taken to reform the energy sector and their effect on various groups of poor households. The paper analyses the pattern of energy supply to, and use by, poor households and explores the link-or its absence-to energy policy. We investigate what works for the poor and which type of reforms and implementation are effective and lead to a transition to more efficient and clean fuels from which the poor benefit. Energy sector reforms when adjusted to the specific conditions of the poor have a positive impact on access and use of clean, safe and efficient fuels. The poor are using gradually less wood as cooking fuel. Gas and kerosene are made more widely available through market liberalisation and subsidy in the particular case of Senegal. Electricity access and use is generally promoted or subsidised through changes in payment conditions and lifeline tariffs

  13. Energy sector reform, energy transitions and the poor in Africa

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Gisela [Energy Research Centre, University of Cape Town, Private Bag, Rondebosch 7701 (South Africa)

    2008-08-15

    There is little systematic information about the impact of energy sector reform on all sources and methods of energy utilised or potentially utilised by the poor. It is not sufficiently known what fuels the poor use, if a larger range of fuels becomes available and affordable and if barriers to access and consumption are reduced. A detailed assessment is presented for four countries, three in Africa (Botswana, Ghana and Senegal) and for comparison one in Latin America (Honduras), of steps taken to reform the energy sector and their effect on various groups of poor households. The paper analyses the pattern of energy supply to, and use by, poor households and explores the link - or its absence - to energy policy. We investigate what works for the poor and which type of reforms and implementation are effective and lead to a transition to more efficient and clean fuels from which the poor benefit. Energy sector reforms when adjusted to the specific conditions of the poor have a positive impact on access and use of clean, safe and efficient fuels. The poor are using gradually less wood as cooking fuel. Gas and kerosene are made more widely available through market liberalisation and subsidy in the particular case of Senegal. Electricity access and use is generally promoted or subsidised through changes in payment conditions and lifeline tariffs. (author)

  14. Depth sectioning using electron energy loss spectroscopy

    International Nuclear Information System (INIS)

    D'Alfonso, A J; Findlay, S D; Allen, L J; Cosgriff, E C; Kirkland, A I; Nellist, P D; Oxley, M P

    2008-01-01

    The continued development of electron probe aberration correctors for scanning transmission electron microscopy has enabled finer electron probes, allowing atomic resolution column-by-column electron energy loss spectroscopy. Finer electron probes have also led to a decrease in the probe depth of focus, facilitating optical slicing or depth sectioning of samples. The inclusion of post specimen aberration corrected image forming lenses allows for scanning confocal electron microscopy with further improved depth resolution and selectivity. We show that in both scanning transmission electron microscopy and scanning confocal electron microscopy geometries, by performing a three dimensional raster scan through a specimen and detecting electrons scattered with a characteristic energy loss, it will be possible to determine the location of isolated impurities embedded within the bulk.

  15. 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.

  16. Energy networks - The data serving the energy transition

    International Nuclear Information System (INIS)

    2017-03-01

    successful outcome of the energy transition. GRTgaz and RTE will also pool their skills in engineering, technical expertise and prospective analysis, governed by two cooperation agreements on: Generating value from gas-electricity coupling: the main topics for 2017 will concern the technical evaluation of Power to Gas and the optimisation of its business model, the development of multi-energy modelling tools, delivering expert advice to regional authorities and assessing the interest of GRTgaz assets participating in RTE systems services. International: this agreement aims to identify areas of synergy to enable joint bids for tenders or to develop international business opportunities mixing electricity and natural gas. This publication proposes maps, graphs and drawings which provide an overview of key data regarding electric power and gas consumption in France, energy production from different sources, a description of the role of networks in energy transition, a description of the role of data availability and use for network managers, and a description of the increasing complementarity of the different energies

  17. Effect of electron-electron collisions on the phase transition and kinetics of nonequilibrium superconductors

    International Nuclear Information System (INIS)

    Elesin, V.F.; Kashurnikov, V.A.; Kondrashov, V.E.; Shamraev, B.N.

    1983-01-01

    An explicit expression is obtained for the distribution function of excess quasiparticles, taking into account electron-electron collisions in nonequilibrium superconductors. It is shown that the character of the phase transition may change at a definite ratio of the electron-electron and electron-phonon interaction constants: the dependence of the order parameter on the power of the source becomes single-valued. In addition, diffusion instability and paramagnetism of the superconductors arise. The multiplication factor of the excess quasiparticles due to electron-electron collisions and to reabsorption of phonons is calculated

  18. Energy transition, a new French energy model. Future energies, green growth, sustainable jobs

    International Nuclear Information System (INIS)

    Royal, Segolene

    2014-01-01

    This publication introduces the new French energy policy for energy transition. It presents and comments the main orientations defined for this policy and which are at the base of the French law on energy transition for a green growth. Thus, it addresses the following topics: to define common objectives for a successful energy transition, to strengthen France's energy independence and to struggle against climate change; to better insulate buildings to save energy, to reduce energy bills and to create jobs; to develop clean transports to improve air quality and to protect the health of French people; to promote renewable energies to diversify energies and to valorise resources of French territories; to struggle against wastage and to promote circular economy from product design to product recycling; to simplify and clarify procedures aimed at improving efficiency and competitiveness; to strengthen nuclear safety and citizen information; and to provide citizen, enterprises, territories and the State with the power to act together

  19. Energy transition within an alter-globalization perspective

    International Nuclear Information System (INIS)

    Combes, Maxime; Azam, Genevieve; Balvet, Jacqueline; Planche, Jeanne; Sabatier, Gilles

    2013-05-01

    This publication proposes a discussion of the present and general energy transition according to seven principles: 1) to stop the current energy transition is an imperious necessity; 2) energy sobriety to meet climatic requirements; 3) to avoid the technical-scientific trap in order to re-politicise energy transition; 4) to disconnect finance and energy in order to take back the control of it; 5) to de-merchandise energy to build up equality; 6) to build up the resilience of territories and of people; 7) energy as a common good, beyond State and market

  20. Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Seletskiy, Sergei M. [Univ. of Rochester, NY (United States)

    2005-01-01

    Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the ¯rst cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cool- ing. The Recycler Electron Cooler (REC) is the key component of the Teva- tron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV car- rying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 ¹rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible.

  1. 77 FR 47692 - Notice of Transportation Services' Transition From Paper to Electronic Fare Media Comments...

    Science.gov (United States)

    2012-08-09

    ... and effective electronic fare media transition to its participating transit benefit agencies... New Program Distribution Methodology for Transit Benefits This section presents a summary of the..., 2012 on TRANServe's adoption of a new program distribution methodology for transit benefits and...

  2. Hydrostatic-pressure effects on the correlated electron-hole transition energies in GaAs-Ga{sub 1-x}Al{sub x}As semiconductor quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Raigoza, N. [Instituto de Fisica, Universidad de Antioquia, AA 1226, Medellin (Colombia); Instituto de Fisica, Unicamp, CP 6165, Campinas, Sao Paulo, 13083-970 (Brazil); Duque, C.A. [Instituto de Fisica, Universidad de Antioquia, AA 1226, Medellin (Colombia); Reyes-Gomez, E. [Dept. of Theor. Physics, Univ. of Havana, San Lazaro y L, Vedado 10400, Havana (Cuba); Instituto de Fisica, Unicamp, CP 6165, Campinas, Sao Paulo, 13083-970 (Brazil); Oliveira, L.E. [Instituto de Fisica, Unicamp, CP 6165, Campinas, Sao Paulo, 13083-970 (Brazil)

    2006-03-01

    The effects of hydrostatic pressure on the correlated e-h transition energies in single GaAs-Ga{sub 1-x}Al{sub x}As quantum wells are calculated via a variational procedure, in the framework of the effective-mass and non-degenerate parabolic-band approximations. The valence-band anisotropy is included in our theoretical model by using different hole masses in different spatial directions. Both heavy- and light-hole exciton energies are obtained, and correlated e-h transition energies are found in good agreement with available experimental measurements. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Universal Quantum Criticality in the Metal-Insulator Transition of Two-Dimensional Interacting Dirac Electrons

    Directory of Open Access Journals (Sweden)

    Yuichi Otsuka

    2016-03-01

    Full Text Available The metal-insulator transition has been a subject of intense research since Mott first proposed that the metallic behavior of interacting electrons could turn to an insulating one as electron correlations increase. Here, we consider electrons with massless Dirac-like dispersion in two spatial dimensions, described by the Hubbard models on two geometrically different lattices, and perform numerically exact calculations on unprecedentedly large systems that, combined with a careful finite-size scaling analysis, allow us to explore the quantum critical behavior in the vicinity of the interaction-driven metal-insulator transition. Thereby, we find that the transition is continuous, and we determine the quantum criticality for the corresponding universality class, which is described in the continuous limit by the Gross-Neveu model, a model extensively studied in quantum field theory. Furthermore, we discuss a fluctuation-driven scenario for the metal-insulator transition in the interacting Dirac electrons: The metal-insulator transition is triggered only by the vanishing of the quasiparticle weight, not by the Dirac Fermi velocity, which instead remains finite near the transition. This important feature cannot be captured by a simple mean-field or Gutzwiller-type approximate picture but is rather consistent with the low-energy behavior of the Gross-Neveu model.

  4. Spin delocalization phase transition in a correlated electrons model

    International Nuclear Information System (INIS)

    Huerta, L.

    1990-11-01

    In a simplified one-site model for correlated electrons systems we show the existence of a phase transition corresponding to spin delocalization. The system becomes a solvable model and zero-dimensional functional techniques are used. (author). 7 refs, 3 figs

  5. Ultrafast Hot Electron Induced Phase Transitions in Vanadium Dioxide

    Directory of Open Access Journals (Sweden)

    Haglund R. F.

    2013-03-01

    Full Text Available The Au/Cr/VO2/Si system was investigated in pump–probe experiments. Hot-electrons generated in the Au were found to penetrate into the underlying VO2 and couple with its lattice inducing a semiconductor-to-metal phase transition in ~2 picoseconds.

  6. Phase engineering of monolayer transition-metal dichalcogenide through coupled electron doping and lattice deformation

    International Nuclear Information System (INIS)

    Ouyang, Bin; Lan, Guoqiang; Song, Jun; Guo, Yinsheng; Mi, Zetian

    2015-01-01

    First-principles calculations were performed to investigate the phase stability and transition within four monolayer transition-metal dichalcogenide (TMD) systems, i.e., MX 2 (M = Mo or W and X = S or Se) under coupled electron doping and lattice deformation. With the lattice distortion and electron doping density treated as state variables, the energy surfaces of different phases were computed, and the diagrams of energetically preferred phases were constructed. These diagrams assess the competition between different phases and predict conditions of phase transitions for the TMDs considered. The interplay between lattice deformation and electron doping was identified as originating from the deformation induced band shifting and band bending. Based on our findings, a potential design strategy combining an efficient electrolytic gating and a lattice straining to achieve controllable phase engineering in TMD monolayers was demonstrated

  7. Electron correlation energy in confined two-electron systems

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, C.L. [Chemistry Program, Centre College, 600 West Walnut Street, Danville, KY 40422 (United States); Montgomery, H.E., E-mail: ed.montgomery@centre.ed [Chemistry Program, Centre College, 600 West Walnut Street, Danville, KY 40422 (United States); Sen, K.D. [School of Chemistry, University of Hyderabad, Hyderabad 500 046 (India); Thompson, D.C. [Chemistry Systems and High Performance Computing, Boehringer Ingelheim Pharamaceuticals Inc., 900 Ridgebury Road, Ridgefield, CT 06877 (United States)

    2010-09-27

    Radial, angular and total correlation energies are calculated for four two-electron systems with atomic numbers Z=0-3 confined within an impenetrable sphere of radius R. We report accurate results for the non-relativistic, restricted Hartree-Fock and radial limit energies over a range of confinement radii from 0.05-10a{sub 0}. At small R, the correlation energies approach limiting values that are independent of Z while at intermediate R, systems with Z{>=}1 exhibit a characteristic maximum in the correlation energy resulting from an increase in the angular correlation energy which is offset by a decrease in the radial correlation energy.

  8. Electron correlations in narrow energy bands: modified polar model approach

    Directory of Open Access Journals (Sweden)

    L. Didukh

    2008-09-01

    Full Text Available The electron correlations in narrow energy bands are examined within the framework of the modified form of polar model. This model permits to analyze the effect of strong Coulomb correlation, inter-atomic exchange and correlated hopping of electrons and explain some peculiarities of the properties of narrow-band materials, namely the metal-insulator transition with an increase of temperature, nonlinear concentration dependence of Curie temperature and peculiarities of transport properties of electronic subsystem. Using a variant of generalized Hartree-Fock approximation, the single-electron Green's function and quasi-particle energy spectrum of the model are calculated. Metal-insulator transition with the change of temperature is investigated in a system with correlated hopping. Processes of ferromagnetic ordering stabilization in the system with various forms of electronic DOS are studied. The static conductivity and effective spin-dependent masses of current carriers are calculated as a function of electron concentration at various DOS forms. The correlated hopping is shown to cause the electron-hole asymmetry of transport and ferromagnetic properties of narrow band materials.

  9. Energy transition: which opportunities for the French industry?

    International Nuclear Information System (INIS)

    Bousson, Guillaume; Pouzeratte, Francois; Pierret, Christian; Bensasson, Bruno; Bouttes, Jean-Paul; Bouygues, Olivier; Durdilly, Robert; Geoffron, Patrice; Ladoucette, Philippe de; Lepercq, Thierry; Maillard, Dominique; Rosier, Philippe; Sauquet, Philippe

    2014-05-01

    Regulatory requirements introduced by the new policy of energy transition will force the French industry to look for alternatives to oil and coal. Within this context, this publication contains contributions proposed by industrial and academic experts which aim at discussing how the French industry can seize the opportunity of energy transition to strengthen itself. The authors discuss the issue of competitiveness, the role of de-carbonated electricity, the context of energy transition in France, the evolutions and transformations of the energy market. They also outline the lack of an energy vision in France, the role of the electricity grid as a vector of energy transition, and the fact that the debate on energy transition did not result in concrete solutions

  10. Proceedings of the European Conferences on the energy transition

    International Nuclear Information System (INIS)

    Vergriete, Patrice; Juppe, Alain; Lechevin, Bruno; Delevoye, Jean-Paul; Ben Naceur, Kamel; Lemmet, Sylvie; Marignac, Yves; Berhault, Gilles; Baupin, Denis; Fremont, Jean-Pierre; Roumet, Claire; Ruedinger, Andreas; Rousset, Sophie; Lechevin, Bruno; Castelain, Damien; Monloubou, Philippe; Sauvage, Edouard; Viveret, Patrick; Marland, Peter; Bouchart, Christiane; Vamberg, Henriette; Watteeuw, Filip; Soubeste, Jean-Marc; Geoffroy, Helene; Couet, Emmanuel; Pellerin, Isabelle; Garnier, Nicolas; Frank, Bo; Bjoerkmarker, Aasa Karlsson; Santais, Beatrice; Roger, Christian; Careme, Damien; Aubry, Christine; Dubbeling, Marielle; Fernandes, Jose Sa; Framond, Alain de; Vansintjan, Dirk; Servais, Olivier; Leclercq, Michel; Poize, Noemie; Sefcovic, Maros; Royal, Segolene; Vincent, Isabelle; Gaudin, Thomas; Bailleul, David; Establie d'Argence, Marie-Pierre; Poncet, Emmanuel

    2016-01-01

    This huge publication contains contributions and sessions of a conference which addressed the following issues: new abilities and professions in the energy sector, perspectives for local and energy policies and for the society after the COP21 and the role of local communities (tools and actions, education, development of cold networks, and so on), a discussion about what happened during the past year with notably the French law for energy transition and a green growth, an overview of the GRHYD demonstrator (the first Power-to-Gas demonstrator in France), how to finance energy transition, how to shift towards a societal transition, sustainable mobility (a city without car made by its inhabitants), urban agriculture as a lever for action for energy transition, the role of citizen in tomorrow's energy, the post-COP21 European, national and local agenda, energy transition and jobs. Workshops and forums related to various aspects related to these issues are also reported

  11. Power electronics - The key technology for Renewable Energy Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Ma, Ke; Yang, Yongheng

    2014-01-01

    The energy paradigms in many countries (e.g. Germany and Denmark) have experienced a significant change from fossil-based resources to clean renewables (e.g. wind turbines and photovoltaics) in the past few decades. The scenario of highly penetrated renewables is going to be further enhanced...... - Denmark expects to be 100 % fossil-free by 2050. Consequently, it is required that the production, distribution and use of the energy should be as technologically efficient as possible and incentives to save energy at the end-user should also be strengthened. In order to realize the transition smoothly...... and effectively, energy conversion systems, currently based on power electronics technology, will again play an essential role in this energy paradigm shift. Using highly efficient power electronics in power generation, power transmission/distribution and end-user application, together with advanced control...

  12. Measurement of few-electron uranium ions on a high-energy electron beam ion trap

    International Nuclear Information System (INIS)

    Beiersdorfer, P.

    1994-01-01

    The high-energy electron beam ion trap, dubbed Super-EBIT, was used to produce, trap, and excite uranium ions as highly charged as fully stripped U 92+ . The production of such highly charged ions was indicated by the x-ray emission observed with high-purity Ge detectors. Moreover, high-resolution Bragg crystal spectromters were used to analyze the x-ray emission, including a detailed measurement of both the 2s 1/2 -2p 3/2 electric dipole and 2p 1/2 -2p 3/2 magnetic dipole transitions. Unlike in ion accelerators, where the uranium ions move at relativistic speeds, the ions in this trap are stationary. Thus very precise measurements of the transition energies could be made, and the QED contribution to the transition energies could be measured within less than 1 %. Details of the production of these highly charged ions and their measurement is given

  13. Electron capture and energy-gain spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Taulbjerg, K.

    1989-01-01

    The applicability of translation energy spectroscopy as a tool to determine individual reaction cross sections in atomic collisions is analyzed with special emphasis on the electron capture process in highly charged ion collisions. A condition is derived to separate between higher collision energies where translation energy spectroscopy is problem free and lower energies where strong overlap of individual spectra features prohibits an analysis of the total translation energy spectrum by means of a simple deconvolution procedure. 8 refs., 6 figs.

  14. Energy loss and thermalization of low-energy electrons

    International Nuclear Information System (INIS)

    LaVerne, J.A.; Mozumder, A.; Notre Dame Univ., IN

    1984-01-01

    Various processes involved in the moderation of low-energy electrons (< 10 keV in energy) have been delineated in gaseous and liquid media. The discussion proceeds in two stages. The first stage ends and the second stage begins when the electron energy equals the first excitation potential of the medium. The second stage ends with thermalization. Cross sections for electronic excitation and for the excitation (and de-excitation) of sub-electronic processes have been evaluated and incorporated in suitable stopping power and transport theories. Comparison between experiment and theory and intercomparisons between theories and experiments have been provided where possible. (author)

  15. Energy storage deployment and innovation for the clean energy transition

    Science.gov (United States)

    Kittner, Noah; Lill, Felix; Kammen, Daniel M.

    2017-09-01

    The clean energy transition requires a co-evolution of innovation, investment, and deployment strategies for emerging energy storage technologies. A deeply decarbonized energy system research platform needs materials science advances in battery technology to overcome the intermittency challenges of wind and solar electricity. Simultaneously, policies designed to build market growth and innovation in battery storage may complement cost reductions across a suite of clean energy technologies. Further integration of R&D and deployment of new storage technologies paves a clear route toward cost-effective low-carbon electricity. Here we analyse deployment and innovation using a two-factor model that integrates the value of investment in materials innovation and technology deployment over time from an empirical dataset covering battery storage technology. Complementary advances in battery storage are of utmost importance to decarbonization alongside improvements in renewable electricity sources. We find and chart a viable path to dispatchable US$1 W-1 solar with US$100 kWh-1 battery storage that enables combinations of solar, wind, and storage to compete directly with fossil-based electricity options.

  16. The coming sustainable energy transition: History, strategies, and outlook

    International Nuclear Information System (INIS)

    Solomon, Barry D.; Krishna, Karthik

    2011-01-01

    Facing global climate change and scarce petroleum supplies, the world must switch to sustainable energy systems. While historical transitions between major energy sources have occurred, most of these shifts lasted over a century or longer and were stimulated by resource scarcity, high labor costs, and technological innovations. The energy transition of the 21st century will need to be more rapid. Unfortunately, little is known about how to accelerate energy transitions. This article reviews past transitions and factors behind them, along with their time frames. Three modern case studies are discussed: Brazil, which shifted from an oil-based transportation system to one based on sugarcane-ethanol (success); France, which shifted from oil-fired electric power to nuclear power (success); and the United States, which attempted to shift from foreign oil to a mix of domestic energy resources (failure). Lessons from these attempts to govern energy transitions are discussed. Several policy instruments to accelerate a transition are identified, though even under ideal circumstances a global energy supply transition will be very slow. Given the need to simultaneously implement programs in countries with different political economies, a greater focus on energy efficiency, promotion of Smart Grids, and possibly a new treaty should yield more timely results. - Highlights: → We review the historical evidence on major energy transitions worldwide. → Case studies are presented of successful energy transitions in Brazil and France. → The United States provides an example of an unsuccessful energy transition. → We argue that a transition focused on energy efficiency can occur much more rapidly.

  17. Electronic Structure Evolution across the Peierls Metal-Insulator Transition in a Correlated Ferromagnet

    Directory of Open Access Journals (Sweden)

    P. A. Bhobe

    2015-10-01

    Full Text Available Transition metal compounds often undergo spin-charge-orbital ordering due to strong electron-electron correlations. In contrast, low-dimensional materials can exhibit a Peierls transition arising from low-energy electron-phonon-coupling-induced structural instabilities. We study the electronic structure of the tunnel framework compound K_{2}Cr_{8}O_{16}, which exhibits a temperature-dependent (T-dependent paramagnetic-to-ferromagnetic-metal transition at T_{C}=180  K and transforms into a ferromagnetic insulator below T_{MI}=95  K. We observe clear T-dependent dynamic valence (charge fluctuations from above T_{C} to T_{MI}, which effectively get pinned to an average nominal valence of Cr^{+3.75} (Cr^{4+}∶Cr^{3+} states in a 3∶1 ratio in the ferromagnetic-insulating phase. High-resolution laser photoemission shows a T-dependent BCS-type energy gap, with 2G(0∼3.5(k_{B}T_{MI}∼35  meV. First-principles band-structure calculations, using the experimentally estimated on-site Coulomb energy of U∼4  eV, establish the necessity of strong correlations and finite structural distortions for driving the metal-insulator transition. In spite of the strong correlations, the nonintegral occupancy (2.25 d-electrons/Cr and the half-metallic ferromagnetism in the t_{2g} up-spin band favor a low-energy Peierls metal-insulator transition.

  18. French people, energy transition, and energy savings. IFOP for Energie Perspective

    International Nuclear Information System (INIS)

    Fourquet, Jerome; Chasles-Parot, Marion

    2014-10-01

    After a presentation of the adopted methodology, this report presents under the form of tables, and comments the results of a survey performed on the perception and relationship French people have on and with energy transition and energy savings. Different aspects have been addressed and assessed by this survey: confidence in local authorities, recognition of energy transition, sensitivity of the issue of energy transition, an example of a local authority communication about energy issues, notoriety of subsidies and primes awarded by the local authority for energy-related works, assessment of well-being in housing, housing occupation status, intention to perform energy-related renovation works in the housing, choice between a large national group or a local company to perform these works

  19. Ultrafast Electron Dynamics in Solar Energy Conversion.

    Science.gov (United States)

    Ponseca, Carlito S; Chábera, Pavel; Uhlig, Jens; Persson, Petter; Sundström, Villy

    2017-08-23

    Electrons are the workhorses of solar energy conversion. Conversion of the energy of light to electricity in photovoltaics, or to energy-rich molecules (solar fuel) through photocatalytic processes, invariably starts with photoinduced generation of energy-rich electrons. The harvesting of these electrons in practical devices rests on a series of electron transfer processes whose dynamics and efficiencies determine the function of materials and devices. To capture the energy of a photogenerated electron-hole pair in a solar cell material, charges of opposite sign have to be separated against electrostatic attractions, prevented from recombining and being transported through the active material to electrodes where they can be extracted. In photocatalytic solar fuel production, these electron processes are coupled to chemical reactions leading to storage of the energy of light in chemical bonds. With the focus on the ultrafast time scale, we here discuss the light-induced electron processes underlying the function of several molecular and hybrid materials currently under development for solar energy applications in dye or quantum dot-sensitized solar cells, polymer-fullerene polymer solar cells, organometal halide perovskite solar cells, and finally some photocatalytic systems.

  20. Electronic Energy Transfer in Polarizable Heterogeneous Environments

    DEFF Research Database (Denmark)

    Svendsen, Casper Steinmann; Kongsted, Jacob

    2015-01-01

    such couplings provide important insight into the strength of interaction between photo-active pigments in protein-pigment complexes. Recently, attention has been payed to how the environment modifies or even controls the electronic couplings. To enable such theoretical predictions, a fully polarizable embedding......-order multipole moments. We use this extended model to systematically examine three different ways of obtaining EET couplings in a heterogeneous medium ranging from use of the exact transition density to a point-dipole approximation. Several interesting observations are made including that explicit use...... of transition densities in the calculation of the electronic couplings - also when including the explicit environment contribution - can be replaced by a much simpler transition point charge description without comprising the quality of the model predictions....

  1. Transition strategy of the transportation energy and powertrain in China

    International Nuclear Information System (INIS)

    Wang Hewu; Ouyang Minggao

    2007-01-01

    The problems of the transportation energy and environment are the major challenges faced globally in the 21st century and are especially serious for China. The future 20 years is the strategic opportunity period of the transition of the transportation energy and powertrain system for China. The greatest characteristics of hydrogen economy lie in its diversity of the primary energy source, the unification of energy carrier and the greening of energy transformation. Development of hydrogen energy transportation powertrain system is suitable for China from the views of the situation of Chinese resources and energy sources, the urban and rural layouts, the superiority of later development and the successful practices of clean cars and electric vehicle development projects. The transition of the transportation energy powertrain system includes three parts: the transition of the energy structure, the transition of the powertrain system and the transition of the fuel infrastructure. The technical pathways of energy powertrain system transition includes expending the use of gaseous fuel to prompt the multiform of the transportation energy and to prepare for the transition of the infrastructure simultaneously, developing and promoting the hybrid technology to solve the current energy and environment problems and to prepare for the transition of powertrain system, and focusing on the research and development and demonstration of fuel cell vehicles and the hydrogen energy technology to prompt the earlier formation of the market of fuel cell vehicles. The goal in the near and medium term of transition is to reduce the fuel consumption by 100 million ton in 2020 by substituting and saving, and the long-term goal is to setup the infrastructure of hydrogen and fuel cell vehicle as the main one replacing the petroleum internal combustion engine vehicle. In order to realize the strategic goals of the transition, the four-phases strategic periods and research and development

  2. NaI(Tl) electron energy resolution

    CERN Document Server

    Mengesha, W

    2002-01-01

    NaI(Tl) electron energy resolution eta sub e was measured using the Modified Compton Coincidence Technique (MCCT). The MCCT allowed detection of nearly monoenergetic internal electrons resulting from the scattering of incident 662 keV gamma rays within a primary NaI(Tl) detector. Scattered gamma rays were detected using a secondary HPGe detector in a coincidence mode. Measurements were carried out for electron energies ranging from 16 to 438 keV, by varying the scattering angle. Measured HPGe coincidence spectra were deconvolved to determine the scattered energy spectra from the NaI(Tl) detector. Subsequently, the NaI(Tl) electron energy spectra were determined by subtracting the energy of scattered spectra from the incident source energy (662 keV). Using chi-squared minimization, iterative deconvolution of the internal electron energy spectra from the measured NaI(Tl) spectra was then used to determine eta sub e at the electron energy of interest. eta sub e values determined using this technique represent va...

  3. Electron scattering by nuclei and transition charge densities

    International Nuclear Information System (INIS)

    Gul'karov, I.S.

    1988-01-01

    Transition charge densities for states of electric type, for nuclei with A≤40--50 as obtained from data on inelastic electron scattering, are studied. The formalism of electroexcitation of nuclei is considered, together with various models (macroscopic and microscopic) used to calculate form factors, transition charge densities, and the moments of these densities: B(Eλ) and R/sub λ/ . The macroscopic models are derived microscopically, and it is shown that the model-independent sum rules lead to the same transition densities as calculations based on various hydrodynamic models. The sum rules with and without allowance for the Skyrme exchange interaction are discussed. The results of the calculations are compared with the experimental form factors of electron scattering by nuclei from 12 C to 48 Ca with excitation in them of normal-parity states with I/sup π/ = 0 + , 1 - , 2 + , 3 - , 4 + , 5 - and T = 0. The model-independent transition charge densities for the weakly collectivized excitations differ strongly from the model-dependent densities. The influence of neutrons on the transition charge densities of the nuclear isotopes 16 /sup ,/ 18 O, 32 /sup ,/ 34 S, and 40 /sup ,/ 48 Ca is considered

  4. Electronic properties and phase transitions in low-dimensional semiconductors

    International Nuclear Information System (INIS)

    Panich, A M

    2008-01-01

    We present the first review of the current state of the literature on electronic properties and phase transitions in TlX and TlMX 2 (M = Ga, In; X = Se, S, Te) compounds. These chalcogenides belong to a family of the low-dimensional semiconductors possessing chain or layered structure. They are of significant interest because of their highly anisotropic properties, semi- and photoconductivity, nonlinear effects in their I-V characteristics (including a region of negative differential resistance), switching and memory effects, second harmonic optical generation, relaxor behavior and potential applications for optoelectronic devices. We review the crystal structure of TlX and TlMX 2 compounds, their transport properties under ambient conditions, experimental and theoretical studies of the electronic structure, transport properties and semiconductor-metal phase transitions under high pressure, and sequences of temperature-induced structural phase transitions with intermediate incommensurate states. The electronic nature of the ferroelectric phase transitions in the above-mentioned compounds, as well as relaxor behavior, nanodomains and possible occurrence of quantum dots in doped and irradiated crystals is discussed. (topical review)

  5. Bremsstrahlung of La and its dependence on electron energy

    International Nuclear Information System (INIS)

    Riehle, F.

    1977-01-01

    Measurements of La-bremsstrahlung isocromates with high resolution for quantum energies between 135 eV and 1867 eV are presented and discussed. In the whole energy range investigated, the isocromate structure, identified with the 4f band of La, is placed 5,45 +- 10,1 eV above the Fermi level. This is in contradiction with a calculation of Gloetzel, which predicts the 4f band maximum about 3eV above the Fermi level. This discrepancy is explained in the present work by the fact that the La electronic density of states depends on the occupation number of the states. The bremsstrahlung isocromate has to be considered as a direct copy of the La ion density of states, consisting of the La-atom and the additional primary electron. Resonance like intensity modulations of the x-ray radiation, resulting from transitions of the primary electron in f-like final states, are observed in an analysis of the La-bremsstrahlung isochromate energy dependence. For transitions of the primary electron in d-like final states, no resonances have been found. The energy dependence of the scattering probability in f-like final states can be explained by a model which assumes the final state as composed by a continuum state and a discrete state. (orig.) [de

  6. Nuclear Excitation by Electronic Transition of U-235

    Energy Technology Data Exchange (ETDEWEB)

    Chodash, Perry Adam [Univ. of California, Berkeley, CA (United States)

    2015-07-14

    Nuclear excitation by electronic transition (NEET) is a rare nuclear excitation that is theorized to occur in numerous isotopes. One isotope in particular, 235U, has been studied several times over the past 40 years and NEET of 235U has never been conclusively observed. These past experiments generated con icting results with some experiments claiming to observe NEET of 235U and others setting limits for the NEET rate. This dissertation discusses the latest attempt to measure NEET of 235U. If NEET of 235U were to occur, 235mU would be created. 235mU decays by internal conversion with a decay energy of 76 eV and a half-life of 26 minutes. A pulsed Nd:YAG laser operating at 1064 nm with a pulse energy of 789 mJ and a pulse width of 9 ns was used to generate a uranium plasma. The plasma was captured on a catcher plate and electrons emitted from the catcher plate were accelerated and focused onto a microchannel plate detector. A decay of 26 minutes would suggest the creation of 235mU and the possibility that NEET occurred. However, measurements performed using a variety of uranium targets spanning depleted uranium up to 99.4% enriched uranium did not observe a 26 minute decay. Numerous other decays were observed with half-lives ranging from minutes up to hundreds of minutes. While NEET of 235U was not observed during this experiment, an upper limit for the NEET rate of 235U was determined. In addition, explanations for the con icting results from previous experiments are given. Based on the results of this experiment and the previous experiments looking for NEET of 235U, it is likely that NEET of 235U has never been observed.

  7. Can Low Energy Electrons Affect High Energy Physics Accelerators?

    International Nuclear Information System (INIS)

    Cimino, Roberto

    2004-01-01

    The properties of the electrons participating in the build up of an electron cloud (EC) inside the beam-pipe have become an increasingly important issue for present and future accelerators whose performance may be limited by this effect. The EC formation and evolution are determined by the wall-surface properties of the accelerator vacuum chamber. Thus, the accurate modeling of these surface properties is an indispensible input to simulation codes aimed at the correct prediction of build-up thresholds, electron-induced instability or EC heat load. In this letter, we present the results of surface measurements performed on a prototype of the beam screen adopted for the Large Hadron Collider (LHC), which presently is under construction at CERN. We have measured the total secondary electron yield (SEY) as well as the related energy distribution curves (EDC) of the secondary electrons as a function of incident electron energy. Attention has been paid, for the first time in this context, to the probability at which low-energy electrons (<∼ 20 eV) impacting on the wall create secondaries or are elastically reflected. It is shown that the ratio of reflected to true-secondary electrons increases for decreasing energy and that the SEY approaches unity in the limit of zero primary electron energy

  8. Identifying blocks to boost industrial development indispensable to energy transition

    International Nuclear Information System (INIS)

    2012-11-01

    For different sectors (biomass energy, fossil and geothermal energies, nuclear energies, solar energy, marine, hydraulic and wind energies, energies in transports, construction, industries and agriculture, prospective and education, grids and storage), this report gives a brief overview of the present status and problematic, and briefly presents the main issues to be solved to develop these sectors within the perspective of energy transition and sustainable development

  9. The household energy transition in India and China

    International Nuclear Information System (INIS)

    Pachauri, Shonali; Jiang, Leiwen

    2008-01-01

    Both India and China are countries in energy transition. This paper compares the household energy transitions in these nations through the analysis of both aggregate statistics and nationally representative household surveys. The two countries differ sharply in several respects. Residential energy consumption in China is twice that in India, in aggregate terms. In addition, Chinese households have almost universal access to electricity, while in India almost half of rural households and 10% of urban households still lack access. On aggregate, urban households in China also derive a larger share of their total energy from liquid fuels and grids (77%) as compared to urban Indian households (65%). Yet, at every income level, Indians derive a slightly larger fraction of their total household energy needs from liquid and grid sources of energy than Chinese with comparable incomes. Despite these differences, trends in energy use and the factors influencing a transition to modern energy in both nations are similar. Compared with rural households, urban households in both nations consume a disproportionately large share of commercial energy and are much further along in the transition to modern energy. However, total energy consumption in rural households exceeds that in urban households, because of a continued dependence on inefficient solid fuels, which contribute to over 85% of rural household energy needs in both countries. In addition to urbanisation, key drivers of the transition in both nations include income, energy prices, energy access and local fuel availability. (author)

  10. Food irradiation by low energy electrons

    International Nuclear Information System (INIS)

    Bird, J.R.

    1985-01-01

    For some special cases, the use of low energy electrons has advantages over the use of gamma-rays or higher energy electrons for the direct irradiation of food. These advantages arise from details of the interaction processes which are responsible for the production of physical, chemical and biological effects. Factors involved include depth of penetration, dose distribution, irradiation geometry, the possible production of radioactivity and costs

  11. Surface sterilization by low energy electron beams

    International Nuclear Information System (INIS)

    Sekiguchi, Masayuki; Tabei, Masae

    1989-01-01

    The germicidal effectiveness of low energy electron beams (175 KV) against bacterial cells was investigated. The dry spores of Bacillus pumilus ATCC 27142 and Bacillus globigii ATCC 9372 inoculated on carrier materials and irradiated by gamma rays showed the exponential type of survival curves whereas they showed sigmoidal ones when exposed to low energy electron beams. When similarly irradiated, the wet spores inoculated on membrane filter showed the same survival curves as the dry spores inoculated on carrier materials. The wet vegetative cells of Escherichia coli ATCC 25922 showed exponential curves when exposed to gamma and electron beam irradiation. Low energy electron beams in air showed little differences from nitrogen stream in their germicidal effectiveness against dry spores of B. pumilus. The D values of B. pumilus spores inoculated on metal plates decreased as the amounts of backscattering electrons from the plates increased. There was adequate correlation between the D value (linear region of survival curve), average D value (6D/6) and 1% survival dose and backscattering factor. Depth dose profile and backscatterig dose of low energy electron beams were measured by radiochromic dye film dosimeter (RCD). These figures were not always in accord with the observed germicidal effectiveness against B. pumilus spores because of varying thickness of RCD and spores inoculated on carrier material. The dry spores were very thin and this thinness was useful in evaluating the behavior of low energy electrons. (author)

  12. High energy electron multibeam diffraction and imaging

    International Nuclear Information System (INIS)

    Bourret, Alain.

    1980-04-01

    The different theories of dynamical scattering of electrons are firstly reviewed with special reference to their basis and the validity of the different approximations. Then after a short description of the different experimental set ups, structural analysis and the investigation of the optical potential by means of high energy electrons will be surveyed

  13. Electron energy-distribution functions in gases

    International Nuclear Information System (INIS)

    Pitchford, L.C.

    1981-01-01

    Numerical calculation of the electron energy distribution functions in the regime of drift tube experiments is discussed. The discussion is limited to constant applied fields and values of E/N (ratio of electric field strength to neutral density) low enough that electron growth due to ionization can be neglected

  14. Coherent transition radiation from a laser wakefield accelerator as an electron bunch diagnostic

    International Nuclear Information System (INIS)

    Tilborg, J. van; Geddes, C.G.R.; Toth, C.; Esarey, E.; Schroeder, C.B.; Martin, M.C.; Hao, Z.; Leemans, W.P.

    2004-01-01

    The observation and modeling of coherent transition radiation from femtosecond laser accelerated electron bunches is discussed. The coherent transition radiation, scaling quadratically with bunch charge, is generated as the electrons transit the plasma-vacuum boundary. Due to the limited transverse radius of the plasma boundary, diffraction effects will strongly modify the angular distribution and the total energy radiated is reduced compared to an infinite transverse boundary. The multi-nC electron bunches, concentrated in a length of a few plasma periods (several tens of microns), experience partial charge neutralization while propagating inside the plasma towards the boundary. This reduces the space-charge blowout of the beam, allowing for coherent radiation at relatively high frequencies (several THz). The charge distribution of the electron bunch at the plasma-vacuum boundary can be derived from Fourier analysis of the coherent part of the transition radiation spectrum. A Michelson interferometer was used to measure the coherent spectrum, and electron bunches with duration on the order of 50 fs (rms) were observed

  15. Transition and Electron Impact Excitation Collision Rates for O III

    Science.gov (United States)

    Tayal, S. S.; Zatsarinny, O.

    2017-12-01

    Transition probabilities, electron excitation collision strengths, and rate coefficients for a large number of O III lines over a broad wavelength range, from the infrared to ultraviolet, have been reported. The collision strengths have been calculated in the close-coupling approximation using the B-spline Breit-Pauli R-matrix method. The multiconfiguration Hartree-Fock method in combination with B-spline expansions is employed for an accurate representation of the target wave functions. The close-coupling expansion contains 202 O2+ fine-structure levels of the 2{s}22{p}2,2s2{p}3, 2{p}4,2{s}22p3s,3p,3d, 4s,4p,4d,4f,5s, and 2s2{p}33s,3p,3d configurations. The effective collision strengths are obtained by averaging electron excitation collision strengths over a Maxwellian distribution of velocities at electron temperatures ranging from 100 to 100,000 K. The calculated effective collision strengths have been reported for the 20,302 transitions between all 202 fine-structure levels. There is an overall good agreement with the recent R-matrix calculations by Storey et al. for the transitions between all levels of the ground 2{s}22{p}2 configuration, but significant discrepancies have been found with Palay et al. for transitions to the 2{s}22{p}2 1 S 0 level. Line intensity ratios between the optical lines arising from the 2{s}22{p}2{}3{P}{0,1,2} - 1 D 2 transitions have been compared with other calculations and observations from the photoionized gaseous nebulae, and good agreement is found. The present calculations provide the most complete and accurate data sets, which should allow a more detailed treatment of the available measured spectra from different ground and space observatories.

  16. Compact multi-energy electron linear accelerators

    International Nuclear Information System (INIS)

    Tanabe, E.; Hamm, R.W.

    1985-01-01

    Two distinctly different concepts that have been developed for compact multi-energy, single-section, standing-wave electron linear accelerator structures are presented. These new concepts, which utilize (a) variable nearest neighbor couplings and (b) accelerating field phase switching, provide the capability of continuously varying the electron output energy from the accelerator without degrading the energy spectrum. These techniques also provide the means for continuously varying the energy spectrum while maintaining a given average electron energy, and have been tested successfully with several accelerators of length from 0.1 m to 1.9 m. Theoretical amd experimental results from these accelerators, and demonstrated applications of these techniques to medical and industrial linear accelerator technology will be described. In addition, possible new applications available to research and industry from these techniques are presented. (orig.)

  17. Matrix elements of the relativistic electron-transition operators

    International Nuclear Information System (INIS)

    Rudzikas, Z.B.; Slepcov, A.A.; Kickin, I.S.

    1976-01-01

    The formulas, which enable us to calculate the electric and magnetic multipole transition probabilities in relativistic approximation under various gauge conditions of the electromagnetic potential, are presented. The numerical values of the coefficients of the one-electron reduced matrix elements of the relativistic operators of the electric and magnetic dipole transitions between the configurations K 0 n 2 l 2 j 2 α 0 J 0 j 2 J--K 0 n 1 l 1 j 1 α 0 'J 0 'j 1 J', where K 0 represents any electronic configuration, having the quantum number of the total angular momentum 0 less than or equal to J 0 less than or equal to 8 (the step is 1 / 2 ), and 1 / 2 less than or equal to j 2 , j 1 less than or equal to 7 / 2 , are given

  18. Transition and synchrotron radiation produced by electrons and particle discrimination

    International Nuclear Information System (INIS)

    Merkel, B.; Repellin, J.-P.; Sauvage, G.; Chollet, J.C.; Dialinas, M.; Gaillard, J.-M.; Hrisoho, A.; Jean, P.

    1976-01-01

    Transition radiation from a radiator of 650 lithium foils has been studied in a multiwire proportional chamber filled with a Xenon-CO 2 mixture for two experimental configurations. With the chamber immediately after the radiator, particle discrimination comparable to those reported in the litterature (90% efficiency for electrons, 10% for hadrons) have been observed. With magnetic bending between the radiator and the xenon chamber typical efficiencies of 87% for electrons and less than 0.4% for hadrons have been measured. The discrimination obtained is at least a factor 20 better than for the more conventional configuration. In the latter case, synchrotron radiation has also been observed

  19. High energy electron positron physics

    International Nuclear Information System (INIS)

    Ali, A.; Soding, P.

    1987-01-01

    With the termination of the physics program at PETRA in a year from now, and with the start of TRISTAN and the SLC and later LEP, an era of e/sup +/e/sup -/ physics will come to an end and a new one begins. The field is changing from a field of a few specialists, to becoming one of the mainstream efforts of the high energy community. It seems appropriate at this moment to summarize what has been learned over the past years, in a way more useful to any high energy physicist in particular to newcomers in the e/sup +/e/sup -/ field. This is the purpose of the book. This book should be used as a reference for future workers in the field of e/sup +/e/sup -/ interactions. It includes the most relevant data, parametrizations, theoretical background, and a chapter on detectors. Contents: Foreword; Detectors for High Energy e/sup +/e/sup -/ Physics; Lepton Pair Production and Electroweak Parameters; Hadron Production, Strong and Electroweak Properties; tau Physics; Recent Results on the Charm Sector; Bottom Physics; Lifetime Measurements of tau, Charmed and Beauty Hadrons; Υ Spectroscopy; Hadronic Decays of the Υ; Quark and Gluon Fragmentation in the e/sup +/e/sup -/ Continuum; Jet Production and QCD; Two Photon Physics; Search for New Particles

  20. Recombinational laser employing electron transitions of diatomic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Biriukov, A S; Prokhorov, A M; Shelepin, L A; Shirokov, N N

    1974-12-01

    Conditions are established for obtaining laser action in the visible and uv regions of the spectrum, using transitions between electronic states of diatomic molecules during recombination of a dissociated gas. The mechanism of population inversion was studied for the oxygen molecule, and gain estimates were obtained for laser action at a wavelength of 4881 A. The feasibility of laser action at other wavelengths was examined.

  1. The 'Energy transition' generation

    International Nuclear Information System (INIS)

    Bedossa, Bastien; Boutignon, Gregoire; Sivy, Corentin; Bercault, Florian; Cage, Agathe; Mahammedi-Bouzina, Mehdi; Potton, Gregoire

    2015-11-01

    The 'Cartes sur table' think tank aims at leveraging the opinion of young French people (from 20 to 35 years old) politically leaning to the left, in order to let them become actors in French debates, such as the one on the energy transition policy for a 'green growth'. This paper explains the origins and the context of the energy transition policy (the dangers of nuclear power, the high potential of renewable energies, etc.), how to finance the energy transition policy, how to promote energy transition in the daily life (notably in transports and through the struggle against wastage), create a Europe of energy, and so on

  2. Golden mean energy equals highest atomic electron orbital energy

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, Leonard J. [Interdisciplinary Research Club, P.O. Box 371, Monroeville, PA 15146 (United States)], E-mail: LJMalinowski@gmail.com

    2009-12-15

    The golden mean numerical value {phi} = 0.5({radical}5 - 1) has been given a physical manifestation through E infinity theory. This short paper relates the golden mean energy 0.618034 MeV to atomic electron orbitals.

  3. Golden mean energy equals highest atomic electron orbital energy

    International Nuclear Information System (INIS)

    Malinowski, Leonard J.

    2009-01-01

    The golden mean numerical value φ = 0.5(√5 - 1) has been given a physical manifestation through E infinity theory. This short paper relates the golden mean energy 0.618034 MeV to atomic electron orbitals.

  4. Research for the energy turnaround. Phase transitions actively shape. Contributions

    International Nuclear Information System (INIS)

    Szczepanski, Petra; Wunschick, Franziska; Martin, Niklas

    2015-01-01

    The Annual Conference 2014 of the Renewable Energy Research Association was held in Berlin on 6 and 7 November 2014. This book documents the contributions of the conference on research for the energy turnaround, phase transitions actively shape. After an introduction and two contributions to the political framework, the contributions to the economic phases of the energy transition, the phase of the current turn, the phases of social energy revolution, the stages of heat turnaround (Waermewende), and the stages of the mobility turn deal with the stages of development of the energy system. Finally, the Research Association Renewable Energy is briefly presented. [de

  5. Electron energy measurements in pulsating auroras

    International Nuclear Information System (INIS)

    McEwan, D.J.; Yee, E.; Whalen, B.A.; Yau, A.W.

    1981-01-01

    Electron spectra were obtained during two rocket flights into pulsating aurora from Southend, Saskatchewan. The first rocket launched at 1143:24 UT on February 15, 1980 flew into an aurora of background intensity 275 R of N 2 + 4278 A and showing regular pulsations with about a 17 s period. Electron spectra of Maxwellian energy distributions were observed with an average E 0 = 1.5 keV, rising to 1.8 keV during the pulsations. There was one-to-one correspondence between the electron energy modulation and the observed optical pulsations. The second rocket, launched at 1009:10 UT on February 23, flew into a diffuse auroral surface of intensity 800 R of N 2 + 4278 A and with somewhat irregular pulsations. The electron spectra were again of Maxwellian energy distribution with an average E 0 = 1.8 keV increasing to 2.1 keV during the pulsations. The results from these flights suggest that pulsating auroras occurring in the morning sector may be quite commonly excited by low energy electrons. The optical pulsations are due to periodic increases in the energy of the electrons with the source of modulation in the vicintiy of the geomagnetic equatorial plane. (auth)

  6. Electron-atom scattering at intermediate energies

    International Nuclear Information System (INIS)

    Kingston, A.E.; Walters, H.R.J.

    1982-01-01

    The problems of intermediate energy scattering are approached from the low and high energy ends. At low intermediate energies difficulties associated with the use of pseudostates and correlation terms are discussed, special consideration being given to nonphysical pseudoresonances. Perturbation methods appropriate to high intermediate energies are described and attempts to extend these high energy approximations down to low intermediate energies are studied. It is shown how the importance of electron exchange effects develops with decreasing energy. The problem of assessing the 'effective completeness' of pseudostate sets at intermediate energies is mentioned and an instructive analysis of a 2p pseudostate approximation to elastic e - -H scattering is given. It is suggested that at low energies the Pauli Exclusion Principle can act to hide short range defects in pseudostate approximations. (author)

  7. Low Energy Electron Cooler for NICA Booster

    CERN Document Server

    Denisov, A P

    2017-01-01

    BINP has developed an electron cooler to increase the ion accumulation efficiency in the NICA (Nuclotron-based Ion Collider fAcility) heavy ion booster (JINR, Dubna). Adjustment of the cooler magnetic system provides highly homogeneous magnetic field in the cooling section B trans/B long ≤ 4∙10-5 which is vital for efficient electron cooling. First experiments with an electron beam performed at BINP demonstrated the target DC current of 500 mA and electron energy 6 keV.

  8. Large impact of reorganization energy on photovoltaic conversion due to interfacial charge-transfer transitions.

    Science.gov (United States)

    Fujisawa, Jun-ichi

    2015-05-14

    Interfacial charge-transfer (ICT) transitions are expected to be a novel charge-separation mechanism for efficient photovoltaic conversion featuring one-step charge separation without energy loss. Photovoltaic conversion due to ICT transitions has been investigated using several TiO2-organic hybrid materials that show organic-to-inorganic ICT transitions in the visible region. In applications of ICT transitions to photovoltaic conversion, there is a significant problem that rapid carrier recombination is caused by organic-inorganic electronic coupling that is necessary for the ICT transitions. In order to solve this problem, in this work, I have theoretically studied light-to-current conversions due to the ICT transitions on the basis of the Marcus theory with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. An apparent correlation between the reported incident photon-to-current conversion efficiencies (IPCE) and calculated reorganization energies was clearly found, in which the IPCE increases with decreasing the reorganization energy consistent with the Marcus theory in the inverted region. This activation-energy dependence was systematically explained by the equation formulated by the Marcus theory based on a simple excited-state kinetic scheme. This result indicates that the reduction of the reorganization energy can suppress the carrier recombination and enhance the IPCE. The reorganization energy is predominantly governed by the structural change in the chemical-adsorption moiety between the ground and ICT excited states. This work provides crucial knowledge for efficient photovoltaic conversion due to ICT transitions.

  9. Electron energy recuperation in gyrodevices

    International Nuclear Information System (INIS)

    Savilov, A. V.; Nusinovich, G. S.; Sinitsyn, O. V.

    2008-01-01

    For many applications of gyrodevices, it is extremely important to increase their overall efficiency and reduce the power consumption. Therefore, at present, there are many gyrotrons operating with depressed collectors. These gyrotrons and their depressed collectors are typically designed with the use of available numerical codes. This paper is devoted to the analysis of the energy recuperation in gyrotrons, which is performed with the use of the Hamiltonian formalism. Such consideration gives some insight into the physics of gyrodevices and can be useful for estimating the benefits from utilizing depressed collectors. Both single-cavity gyromonotrons and multicavity gyrodevices in which the last cavity is excited by a prebunched beam are analyzed. Special attention is paid to a three-cavity, frequency-quadrupling gyrodevice.

  10. Electron-vibrational transitions under molecular ions collisions with slow electrons

    International Nuclear Information System (INIS)

    Andreev, E.A.

    1993-01-01

    A concept of a multichannel quantum defect is considered and basic theoretic ratios of inelastic collisional processes with the participation of molecular positive ions and slow electrons playing an important role both in atmospheric and laboratory plasma, are presented. The problem of scattering channel number limitation with the provision of S-matrix unique character is considered. Different models of electron rotation-vibrational connection under collision of two-atom molecular ions with slow electrons are analysed. Taking N 2 + as an example, a high efficiency of transitions between different electron states of a molecular ion is shown. 73 refs., 9 figs., 1 tab

  11. 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

  12. Radiation from silver films bombarded by low-energy electrons

    International Nuclear Information System (INIS)

    Chung, M.S.; Callcott, T.A.; Kretschmann, E.; Arakawa, E.T.

    1980-01-01

    Emission spectra from Ag films irradiated by low energy electrons (20-1500 eV) have been measured, and the results compared with theory. For relatively smooth films, two peaks in the spectra are resolved. One at 3.73 eV, the volume plasmon energy, is attributed to transition radiation and/or bremsstrahlung. The second, at about 3.60 eV, is very sensitive to surface roughness in both position and magnitude and is produced by roughness-coupled radiation from surface plasmons. For rough films, the roughness-coupled radiation dominates the emission. In addition to spectral shapes, the polarization of the radiation and its intensity as a function of electron energy were measured. The experimental results are compared with new calculations of roughness-coupled emission which account for most of our observations. They indicate that high wavevector roughness components play the dominant role in the emission process. (orig.)

  13. ANCRE scenarios for energy transition. Report 2013

    International Nuclear Information System (INIS)

    Alazard-Toux, Nathalie; Des Courtils, Nicolas; Hache, Emmanuel; Liegeard, Alban; Lorne, Daphne; Duplan, Jean-Luc; Kalaydjian, Francois; Heintze, Eric; Tilagone, Richard; Henriot, Stephane; Forti, Laurent; Barthelemy, Pascal; Merlen, Elisabeth; Criqui, Patrick; Mathy, Sandrine; Menanteau, Philippe; Devezeaux De Lavergne, Jean-Guy; Avril, Sophie; Cavata, Christian; Le Duigou, Alain; Le Net, Elisabeth; Marcucci-Demeure, Jeanne; Safa, Henri; Topper, Benjamin; Touboul, Francoise; Carre, Franck; Joly, Jean-Pierre; Charbit, Francoise; Mermilliod, Nicole; Mermilliod, Nicole; Le Net, Elisabeth; Teissier, Olivier; Charrue, Herve; Colonna, Paul; Legrand, Jack; Vidal, Olivier; Goffe, Bruno; Mueller, Alex; Flamant, Gilles; Allard, Francis; Most, Jean-Michel; Matarasso, Pierre; Brault, Pascal; Lemoine, Lionel; Achard, Jean-Luc; Uster, Guillaume; Delsey, Jean; Lucchese, Paul; Tadrist, Lounes; Hadjsaid, Nouredine

    2014-01-01

    This report first gives an overview of the energy system by presenting the determining factors of energy demand and of CO 2 emissions per sector (housing and office building, transport, industry, agriculture, forestry and biomass), by analysing energy systems and CO 2 emissions (energy sources, energy vectors, networks and storage, energy and CO 2 assessment for France), and by describing the guidelines of the scenarios proposed by ANCRE. The three main scenarios are characterized by a stronger sobriety, an electricity-based de-carbonation (with a variant based on nuclear and renewable energies), and diversified vectors. They are notably compared to a trend-based reference scenario. Results are discussed in terms of energy consumption (primary and final energy, consumption by the different sectors), of energy production and CO 2 emissions. Scenarios are assessed in terms of economic, environmental and societal, political and strategic criteria. Some consequences for research topics and funding are identified

  14. Investigation of electronic transport properties of some liquid transition metals

    Science.gov (United States)

    Patel, H. P.; Sonvane, Y. A.; Thakor, P. B.

    2018-04-01

    We investigated electronic transport properties of some liquid transition metals (V, Cr, Mn, Fe, Co and Pt) using Ziman formalism. Our parameter free model potential which is realized on ionic and atomic radius has been incorporated with the Hard Sphere Yukawa (HSY) reference system to study the electronic transport properties like electrical resistivity (ρ), thermal conductivity (σ) and thermo electrical power (Q). The screening effect on aforesaid properties has been studied by using different screening functions. The correlations of our results and others data with in addition experimental values are profoundly promising to the researchers working in this field. Also, we conclude that our newly constructed parameter free model potential is capable to explain the aforesaid electronic transport properties.

  15. Low energy electron scattering from fuels

    International Nuclear Information System (INIS)

    Lopes, M. Cristina A.; Silva, Daniel G.M.; Coelho, Rafael F.; Duque, Humberto V.; Santos, Rodrigo R. dos; Ribeiro, Thiago M.

    2011-01-01

    Full text. Accurate and precise values of absolute total cross section (TCS) represent important information in many scientific and technological applications. In our case, for example, we are motivated to provide such information for electron-fuel collision processes which are specifically relevant to modeling spark ignition in alcohol-fuelled internal combustion engines. Many electron scattering TCS measurements are presently available for a diverse range of atomic and molecular targets. However, lack of data for important bio-molecular targets still remains. Disagreements between the available TCS data for the alcohols have prompted several studies of electron scattering collision of slow electrons with these molecules which are currently important in applications as bio- fuels. This relevance, which has attracted much attention, has been one of the subjects of a recent collaboration between experimental and theoretical groups in the USA and Brazil. Recently this collaboration reported first measurements and calculations of differential cross sections for elastic low-energy (rotationally unresolved) electron scattering by several primary alcohols. In this work we address methanol and ethanol TCSs at low energy range and report additional studies of resonant structure in ethanol using the detection of metastable states produced by electron impact excitation with high energy resolution. We have recently constructed a TCS apparatus in our laboratory at Universidade Federal de Juiz de Fora, Brazil, based on the well-known linear transmission technique. The experimental setup is based on the measurement of the attenuation of a collimated electron beam through a gas cell containing the atoms or molecules to be studied at a given pressure. It consists essentially of an electron gun, a gas cell and an electron energy analyzer composed of an array of decelerating electrostatic lenses, a cylindrical dispersive 127o analyzer and a Faraday cup. To our knowledge, there exist

  16. Low energy electron scattering from fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M. Cristina A.; Silva, Daniel G.M.; Coelho, Rafael F.; Duque, Humberto V.; Santos, Rodrigo R. dos; Ribeiro, Thiago M. [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil). Dept. de Fisica; Yates, Brent; Hong, Ling; Khakoo, Murtadha A. [California State University at Fullerton, CA (US). Physics Department; Bettega, Marcio H.F. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Fisica; Costa, Romarly F. da [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas; Lima, Marco A.P. [Laboratorio Nacional de Ciencia e Tecnologia do Bioetanol (CTBE/CNPEM), Campinas, SP (Brazil)

    2011-07-01

    Full text. Accurate and precise values of absolute total cross section (TCS) represent important information in many scientific and technological applications. In our case, for example, we are motivated to provide such information for electron-fuel collision processes which are specifically relevant to modeling spark ignition in alcohol-fuelled internal combustion engines. Many electron scattering TCS measurements are presently available for a diverse range of atomic and molecular targets. However, lack of data for important bio-molecular targets still remains. Disagreements between the available TCS data for the alcohols have prompted several studies of electron scattering collision of slow electrons with these molecules which are currently important in applications as bio- fuels. This relevance, which has attracted much attention, has been one of the subjects of a recent collaboration between experimental and theoretical groups in the USA and Brazil. Recently this collaboration reported first measurements and calculations of differential cross sections for elastic low-energy (rotationally unresolved) electron scattering by several primary alcohols. In this work we address methanol and ethanol TCSs at low energy range and report additional studies of resonant structure in ethanol using the detection of metastable states produced by electron impact excitation with high energy resolution. We have recently constructed a TCS apparatus in our laboratory at Universidade Federal de Juiz de Fora, Brazil, based on the well-known linear transmission technique. The experimental setup is based on the measurement of the attenuation of a collimated electron beam through a gas cell containing the atoms or molecules to be studied at a given pressure. It consists essentially of an electron gun, a gas cell and an electron energy analyzer composed of an array of decelerating electrostatic lenses, a cylindrical dispersive 127o analyzer and a Faraday cup. To our knowledge, there exist

  17. Electron scattering from sodium at intermediate energies

    International Nuclear Information System (INIS)

    Mitroy, J.; McCarthy, I.E.

    1986-10-01

    A comprehensive comparison is made between theoretical calculations and experimental data for intermediate energy (≥ 10 eV) electron scattering from sodium vapour. The theoretical predictions of coupled-channels calculations (including one, two or four channels) do not agree with experimental values of the differential cross sections for elastic scattering or the resonant 3s to 3p excitation. Increasingly-more-sophisticated calculations, incorporating electron correlations in the target states, and also including core-excited states in the close-coupling expansion, are done at a few selected energies in an attempt to isolate the cause of the discrepancies between theory and experiment. It is found that these more-sophisticated calculations give essentially the same results as the two- and four-channel calculations using Hartree-Fock wavefunctions. Comparison of the sodium high-energy elastic differential cross sections with those of neon suggests that the sodium differential cross section experiments may suffer from systematic errors. There is also disagreement, at the higher energies, between theoretical values for the scattering parameters and those that are derived from laser-excited superelastic scattering and electron photon coincidence experiments. When allowance is made for the finite acceptance angle of the electron spectrometers used in the experiments by convoluting the theory with a function representing the distribution of electrons entering the electron spectrometer it is found that the magnitudes of the differences between theory and experiment are reduced

  18. Instantaneous nonvertical electronic transitions with shaped femtosecond laser pulses: Is it possible?

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Møller, Klaus Braagaard

    2003-01-01

    In molecular electronic transitions, a vertical transition can be induced by an ultrashort laser pulse. That is, a replica of the initial nuclear state-times the transition dipole moment of the electronic transition-can be created instantaneously (on the time scale of nuclear motion) in the excited...

  19. Storifying Samsøs Renewable Energy Transition

    DEFF Research Database (Denmark)

    Papazu, Irina

    2018-01-01

    Through a joint community effort Denmark’s Renewable Energy Island Samsø became self-sufficient with renewable energy over a period of 10 years from 1997 to 2007. Today, the story about Samsø’s successful energy transition has become a global export and a widely known model of community building...... the effects of such well-crafted transition narratives. This tendency toward the ‘storification’ of transition processes is not restricted to Samsø; it is employed as a tactics by environmental organizations operating globally....

  20. Probing Critical Point Energies of Transition Metal Dichalcogenides: Surprising Indirect Gap of Single Layer WSe 2

    KAUST Repository

    Zhang, Chendong

    2015-09-21

    By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.

  1. Probing Critical Point Energies of Transition Metal Dichalcogenides: Surprising Indirect Gap of Single Layer WSe 2

    KAUST Repository

    Zhang, Chendong; Chen, Yuxuan; Johnson, Amber; Li, Ming-yang; Li, Lain-Jong; Mende, Patrick C.; Feenstra, Randall M.; Shih, Chih Kang

    2015-01-01

    By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.

  2. A novel transition radiation detector utilizing superconducting microspheres for measuring the energy of relativistic high-energy charged particles

    International Nuclear Information System (INIS)

    Yuan, Luke C.L.; Chen, C.P.; Huang, C.Y.; Lee, S.C.; Waysand, G.; Perrier, P.; Limagne, D.; Jeudy, V.; Girard, T.

    2000-01-01

    A novel transition radiation detector (TRD) utilizing superheated superconducting microspheres of tin of 22-26, 27-32 and 32-38 μm in diameter, respectively, has been constructed which is capable of measuring accurately the energy of relativistic high-energy charged particles. The test has been conducted in a high-energy electron beam facility at the CERN PS in the energy range of 1-10 GeV showing an energy dependence of the TR X-ray photon produced and hence the value γ=E/mc 2 of the charged particle

  3. Emerging Energy Applications of Two-Dimensional Layered Transition Metal Dichalcogenides

    KAUST Repository

    Li, Henan

    2015-10-31

    Transition metal dichalcogenides (TMDCs) have attracted significant attention for their great potential in nano energy. TMDC layered materials represent a diverse and largely untapped source of 2D systems. High-quality TMDC layers with an appropriate size, variable thickness, superior electronic and optical properties can be produced by the exfoliation or vapour phase deposition method. Semiconducting TMDC monolayers have been demonstrated feasible for various energy related applications, where their electronic properties and uniquely high surface areas offer opportunities for various applications such as nano generators, green electronics, electrocatalytic hydrogen generation and energy storage. In this review, we start from the structure, properties and preparation, followed by detailed discussions on the development of TMDC-based nano energy applications. Graphical abstract The structure characterizations and preparative methods of 2D TMDCs have obtained significant progresses. Their recent advances for nano energy generation, solar harvesting, conversion and storage, and green electronics are reviewed.

  4. Optical properties and electronic transitions of zinc oxide, ferric oxide, cerium oxide, and samarium oxide in the ultraviolet and extreme ultraviolet

    DEFF Research Database (Denmark)

    Pauly, N; Yubero, F; Espinós, J P

    2017-01-01

    Optical properties and electronic transitions of four oxides, namely zinc oxide, ferric oxide, cerium oxide, and samarium oxide, are determined in the ultraviolet and extreme ultraviolet by reflection electron energy loss spectroscopy using primary electron energies in the range 0.3-2.0 ke...

  5. Italy: a national energy strategy in transition

    International Nuclear Information System (INIS)

    Spaes, Joel

    2014-01-01

    This article discusses the status and perspectives of the Italian energy policy. It outlines that this policy has known many changes during the past decades. The country has been depending for years on oil imports and on electricity imports from its neighbours even though ENI and ENEL are major world actors. It had chosen nuclear energy to gain independence until the Chernobyl accident which resulted in a moratorium. On the side of renewable energies, Italy has notably developed geothermal energy, and possesses an important hydraulic energy fleet, while solar photovoltaic and wind energy started their development rather late and still at a rather slow pace. Thus, a new energy strategy has been implemented in 2012 with some main objectives: reduction of energy costs, meeting of European objectives regarding energy and climate, improvement of energy supply security and of energy independence, and development of a sustainable economy through the development of the energy sector. This strategy resulted in very good results in terms of energy efficiency, and of growth rate for the photovoltaic sector

  6. Geopolitics of energy in a transition world

    International Nuclear Information System (INIS)

    Giraud, A.

    1995-01-01

    Here is a study about worldwide energy forecasting from an economic analysis of our days, in developed countries, and with a forecasting about energy demand in developing countries. Nuclear power, petroleum, natural gas, coal are studied. The problem of environment protection which help some energy like gas or be prejudicial to some other like coal is evoked. The most important question is about the formidable energy demand for south-east Asia countries and how it will be answered. 13 figs

  7. Lifetime measurements in transitional nuclei by fast electronic scintillation timing

    Science.gov (United States)

    Caprio, M. A.; Zamfir, N. V.; Casten, R. F.; Amro, H.; Barton, C. J.; Beausang, C. W.; Cooper, J. R.; Gürdal, G.; Hecht, A. A.; Hutter, C.; Krücken, R.; McCutchan, E. A.; Meyer, D. A.; Novak, J. R.; Pietralla, N.; Ressler, J. J.; Berant, Z.; Brenner, D. S.; Gill, R. L.; Regan, P. H.

    2002-10-01

    A new generation of experiments studying nuclei in spherical-deformed transition regions has been motivated by the introduction of innovative theoretical approaches to the treatment of these nuclei. The important structural signatures in the transition regions, beyond the basic yrast level properties, involve γ-ray transitions between low-spin, non-yrast levels, and so information on γ-ray branching ratios and absolute matrix elements (or level lifetimes) for these transitions is crucial. A fast electronic scintillation timing (FEST) system [H. Mach, R. L. Gill, and M. Moszyński, Nucl. Instrum. Methods A 280, 49 (1989)], making use of BaF2 and plastic scintillation detectors, has been implemented at the Yale Moving Tape Collector for the measurement of lifetimes of states populated in β^ decay. Experiments in the A100 (Pd, Ru) and A150 (Dy, Yb) regions have been carried out, and a few examples will be presented. Supported by the US DOE under grants and contracts DE-FG02-91ER-40609, DE-FG02-88ER-40417, and DE-AC02-98CH10886 and by the German DFG under grant Pi 393/1.

  8. Financing the alternative: renewable energy in developing and transition countries

    OpenAIRE

    Brunnschweiler, Christa N.

    2006-01-01

    This paper examines the determinants of credit allocation to renewable energy firms in developing and transition countries. Using a simple en- dogenous growth model, we show that the development of the renewable energy sector, i.e. the diversification of renewable energy resources used in primary energy production, depends on the quality of financial intermedia- tion, debtor information costs to banks, and financing needs of renewable energy firms. Policies should aim at increasing financial ...

  9. Electronic market places in the energy

    International Nuclear Information System (INIS)

    Mons, L.

    2001-12-01

    Electronic market places in the energy domain occurred at the end of the 90's in the US and have started to develop in Europe in the year 2000. About 60 platforms are registered today and this development can be explained by the advantages raised by such an infrastructure: simplification of purchase procedures, reduction of delays in the purchase decision, reduction of administrative costs etc.. However, today none of these electronic market places is profitable and several have closed down. On the other hand, this tool will certainly become necessary in the future and all energy actors are developing projects in this way. This study analyzes the electronic market places phenomenon in the energy domain using 10 market places examples with their key-factors of success. It draws out a complete status of the initiatives developed today and presents some scenarios of evolution. (J.S.)

  10. Phase transitions in polypeptides: analysis of energy fluctuations

    DEFF Research Database (Denmark)

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

    2009-01-01

    The helix random coil transition in alanine, valine, and leucine polypeptides consisting of 30 amino acids is studied in vacuo using the Langevin molecular dynamics approach. The influence of side chain radicals on internal energy and heat capacity of the polypeptides is discussed. The heat...... of simulation time. This study provides a comparison of methods for the description of structural transitions in polypeptides....

  11. Equilibrium Transitions from Non Renewable Energy to Renewable Energy under Capacity Constraints

    OpenAIRE

    Amigues, Jean-Pierre; Ayong Le Kama, Alain; Moreaux, Michel

    2013-01-01

    We study the transition between non-renewable and renewable energy sources with adjustment costs over the production capacity of renewable energy. Assuming constant variable marginal costs for both energy sources, convex adjustment costs and a more expensive renewable energy, we show the following. With sufficiently abundant non-renewable energy endowments, the dynamic equilibrium path is composed of a first time phase of only non-renewable energy use followed by a transition phase substituti...

  12. Electron correlation influenced magnetic phase transitions in f-electron systems

    International Nuclear Information System (INIS)

    Frauenheim, T.; Ropke, G.

    1980-01-01

    The temperature-induced phase transition (on lowering the temperature) antiferromagnet-ferromagnet in the heavy rare earth and some of actinide compounds is qualitatively explained in the scope of a two-band Hubbard model and the more complex RKKY model as the result of electron correlation effects in the conduction bands. (orig.)

  13. How can we ensure the energy transition? Comment assurer la transition energetique?

    Energy Technology Data Exchange (ETDEWEB)

    Rojey, Alexandre

    2007-07-01

    With a continuously growing energy demand, the present energy model is clearly unsustainable due to the decline of fossil fuel resources and the risks of climate change A transition towards a sustainable model is therefore needed. However, there are no immediate alternatives leading to a sharp reduction in the use of fossil fuels, which are expected to maintain a major role for many years. The energy transition will therefore require a long time period The risks of climate change will require urgent measures and the 'carbon transition' has to be achieved more rapidly than the energy transition itself. A whole set of solutions will be needed in the technical but also economic and regulatory areas, for achieving a successful transition: energy conservation, diversification of energy . sources, reduction of the carbon content of the energy mix, CO{sub 2}, capture and storage. Hybrid options will be favoured. The paper describes the main features of the upcoming transition and the actions which are required. (auth)

  14. Plasma phase transition in dense hydrogen and electron-hole plasmas

    CERN Document Server

    Filinov, V S; Levashov, P R; Fortov, V E; Ebeling, W; Schlanges, M; Koch, S W

    2003-01-01

    Plasma phase transitions in dense hydrogen and electron-hole plasmas are investigated by direct path integral Monte Carlo methods. The phase boundary of the electron-hole liquid in germanium is calculated and is found to agree reasonably well with the known experimental results. Analogous behaviour is found for high-density hydrogen. For a temperature of T = 10 000 K it is shown that the internal energy is lowered due to droplet formation for densities between 10 sup 2 sup 3 cm sup - sup 3 and 10 sup 2 sup 4 cm sup - sup 3.

  15. Ideal glass transitions in thin films: An energy landscape perspective

    OpenAIRE

    Truskett, Thomas M.; Ganesan, Venkat

    2003-01-01

    We introduce a mean-field model for the potential energy landscape of a thin fluid film confined between parallel substrates. The model predicts how the number of accessible basins on the energy landscape and, consequently, the film's ideal glass transition temperature depend on bulk pressure, film thickness, and the strength of the fluid-fluid and fluid-substrate interactions. The predictions are in qualitative agreement with the experimental trends for the kinetic glass transition temperatu...

  16. The Future of the Energy Transition in Germany

    OpenAIRE

    Gawel, Erik; Lehmann, Paul; Korte, Klaas; Strunz, Sebastian; Bovet, Jana; Köck, Wolfgang; Massier, Philipp; Löschel, Andreas; Schober, Dominik; Ohlhorst, Dörte; Tews, Kerstin; Schreurs, Miranda; Reeg, Matthias; Wassermann, Sandra

    2014-01-01

    Although the goals of the country ’ s energy transition ( Energiewende ) are widely accepted in Germany, the specific route to get there is itself a matter of great controversy. The individual measures that are part of the energy transition policy and the questions of how they interact and how they are embedded in the European context are objects of controversial scientific and public debate. Most recently, the consequences for the price of electricity have, in particular...

  17. Energy Exchange Dynamics across L-H transitions in NSTX

    Science.gov (United States)

    Diallo, Ahmed

    2017-10-01

    H-mode is planned for future devices such as ITER, and is preceded by a low (L) to high (H) transition. A key question remains. What is the mechanism behind the L-H transition? Most theoretical descriptions of the L-H transition are based on the shear of the radial electric field and coincident ExB poloidal flow shear, which is thought to be responsible for the onset of the anomalous transport suppression that leads to the L-H transition. This talk will focus on the analysis of the flow dynamics across the L-H transition in NSTX. We analyze the L-H transition dynamics using the velocimetry of 2D edge turbulence data from gas-puff imaging (GPI). We determine the velocity components at the edge across the L-H transition for 17 discharges with three types of heating power (NBI, ohmic, and RF). Using a reduced model equation of edge flows and turbulence, the energy transfer dynamics is compared with the turbulence depletion hypothesis of the predator-prey model. In order for Reynolds work to suppress the turbulence, it must deplete the total turbulent free energy, including the thermal free-energy term. For this to occur, the increase in kinetic energy in the mean flow over the L-H transition must be comparable to the pre-transition thermal free energy. However, this ratio was found to be of order 10-2. Although there are significant simplifications in the theoretical model, they are unlikely to cause inaccuracy by two orders of magnitude, suggesting that direct turbulence depletion by the Reynolds work may not be large enough to explain the L-H transition on NSTX, contrary to the predator-prey model. This work is supported by the US DOE Contract No. DE-AC02-09CH11466.

  18. Energy in transition. Between regulation and market

    International Nuclear Information System (INIS)

    Horzetzky, Guenther

    2016-01-01

    Actually, the energy industry is affected in a changing market environment. The expansion of the renewables led to a share of about 30 % of the German electricity production and is always rising. The renewables energy levy has reached a level of 6.35 Euro Cents per kWh, which is actually a high level. Investments in new power plants are stopped due to low market electricity prices. The market pressure on the utilities is high and their business models have to be scrutinised. The NRW state government supports the magic political triangle of a secure, affordable and environmentally friendly energy supply. Instead of further interventions we have to develop our existing energy system cautiously. Anything else would not meet the requirements for invests in the energy supply and the magic triangle of energy politics.

  19. 7 key measures for France to enter energy transition

    International Nuclear Information System (INIS)

    Creach, Morgane; Vandaele, Diane; Richard, Marion; Fink, Meike; Quirion, Philippe; Bonduelle, Antoine; Berthier, Julien; Mossalgue, Marc; Louchard, Olivier; Lenoir, Didier; Vormus, Joel; Charru, Madeleine; Claustre, Raphael; Mathis, Paul; Gauthier, Raphaelle; Couturier, Christian; Mijeon, Charlotte; Gavand, Karine; Majnoni d'Intignano, Sophia; Delcroix, Julie

    2012-01-01

    The authors of this report propose, describe and discuss seven measures to be taken to promote and support energy transition in France: to introduce a climate-energy contribution, to adopt a law for a progressive and complete nuclear phasing out, to set local communities at the heart of energy transition, to introduce a mandatory thermal renewal of existing buildings, to develop a less greenhouse gas emitter agricultural model, to enter into a low-carbon and energy efficient transport infrastructure scheme, and to plan the struggle against urban sprawl at the scale of the living area

  20. Energy transition: constraint or opportunity for growth and employment?

    International Nuclear Information System (INIS)

    Vona, Francesco

    2017-01-01

    This note aims at examining whether environmental policies associated with energy transition are either a brake on, or an opportunity for economic growth. In order to so, the authors compare France's situation with that of its economic partners (Germany, Spain, Italy) in terms of energy price, and of share of employment in polluting industries. They also examine the influence of an increase of energy prices on employment and competitiveness of French manufacturing companies. They finally show that energy transition implies a structural change which may result in an actual creation of green jobs. They finally propose three recommendations regarding economic policy

  1. Can urban rail transit curb automobile energy consumption?

    International Nuclear Information System (INIS)

    Lin, Boqiang; Du, Zhili

    2017-01-01

    With the rapid development of China's economy and the speed of urbanization, China's automobile sector has experienced rapid development. The rapid development of the automobile sector has increased energy consumption. According to the results of this paper, automobile energy consumption accounted for about 10.73% of total energy consumption in China in 2015, about 3.6 times the proportion a decade ago. With the deterioration of urban traffic conditions, relying on expanding the amount of vehicles and city road network cannot solve the problem. Urban rail transit is energy-saving and less-polluting, uses less space, has large capacity, and secure. Urban rail transit, according to the principle of sustainable development, is a green transportation system and should be especially adopted for large and medium-sized cities. The paper uses the binary choice model (Probit and Logit) to analyze the main factors influencing the development of rail transit in Chinese cities, and whether automobile energy consumption is the reason for the construction of urban rail transit. Secondly, we analyze the influence of urban rail transit on automobile energy consumption using DID model. The results indicate that the construction of urban rail traffic can restrain automobile energy consumption significantly, with continuous impact in the second year. - Highlights: • Investigate the main factors influencing the building of rail transit for Chinese cities. • Analyze the influence of urban rail transit on automobile energy consumption by DID model. • The results indicate that the construction of urban rail traffic can restrain automobile energy consumption significantly.

  2. Which tools for energy transition and the Energiewende?

    International Nuclear Information System (INIS)

    Barthet, Marie-Claire; Nedey, Fabienne; Tourneur, Jean-Claude

    2015-01-01

    In this set of articles, the first one comments the emergence of standard tools to assess energy efficiency within the frame of energy transition. These standards concern eight different fields and can be applied by enterprises and also used by local communities to assess their energy saving policy. The second article comments the content of a French standard elaborated by a professional association gathering actors of the illuminated sign and signing sector; this standard addresses the design and manufacturing of these products, and technical, energetic as well as aesthetic aspects. The third article presents and comments the application in Bordeaux and in Nantes of a new European directive for public lighting which resulted in a renewal of the installation. The fourth article comments the content of the French law on energy transition, notably regarding the production or improvement of buildings and dwellings to save energy, the development of cleaner transports, waste recycling, the development of renewable energies, and the struggle against energy poverty. The next article reports the main parts of an intervention of the German minister of Foreign Affairs on the German policy for energy transition (the so-called Energiewende). The last article comments the road-map for energy transition in Germany as it has been recently defined by the German government. Several topics are notably addressed: co-generation, energy efficiency, transformation of coal power plants, reduction of CO 2 emissions by the coal industry, extension of the electric grid, financing the dismantling of nuclear power stations

  3. Surface segregation energies in transition-metal alloys

    DEFF Research Database (Denmark)

    Ruban, Andrei; Skriver, Hans Lomholt; Nørskov, Jens Kehlet

    1999-01-01

    We present a database of 24 x 24 surface segregation energies of single transition metal impurities in transition-metal hosts obtained by a Green's-function linear-muffin-tin-orbitals method in conjunction with the coherent potential and atomic sphere approximations including a multipole correction...... to the electrostatic potential and energy. We use the database to establish the major factors which govern surface segregation in transition metal alloys. We find that the calculated trends are well described by Friedel's rectangular state density model and that the few but significant deviations from the simple...

  4. Which role for the nuclear in the energy transition?

    International Nuclear Information System (INIS)

    Ramade, Francois

    2013-05-01

    After having outlined the almost unavoidable character of energy transition, the author shows that a combination of nuclear and renewable energies is the single possibility to maintain a sufficient level of energy production while avoiding a major climate change. He states that the decision to shut down the Fessenheim plant is not a good start for the debate on energy transition. He outlines that the risks evoked to justify this closure are not realistic. He discusses the technical and economic consequences of this closure, how Fessenheim could then be replaced in terms of energy supply. He discusses the relationship between employment on the one side, and nuclear or renewable energies on the other side. He briefly comments the German situation, outlines that nuclear energy is an alternative to the exhaustion of fossil hydrocarbon resources. He finally addresses the issue of definition of the energy mix

  5. General theory for environmental effects on (vertical) electronic excitation energies.

    Science.gov (United States)

    Schwabe, Tobias

    2016-10-21

    Almost 70 years ago, the first theoretical model for environmental effects on electronic excitation energies has been derived. Since then, several different interpretations and refined models have been proposed for the perichromic shift of a chromophore due to its surrounding medium. Some of these models are contradictory. Here, the contributing terms are derived within the framework of long-range perturbation theory with the least approximations so far. The derivation is based on a state-specific interpretation of the interaction energies and all terms can be identified with individual properties of either the chromophore or the surroundings, respectively. Further, the much debated contribution due to transition moments coupled to the environment can be verified in the form of a non-resonant excitonic coupling to the dynamic polarizabilities in the environment. These general insights should clarify discussions and interpretations of environmental effects on electronic excitations and should foster the development of new models for the computation of these effects.

  6. Theoretical studies of the electronic properties of transition metals and transition metal compounds

    International Nuclear Information System (INIS)

    Alward, J.F. Jr.

    1976-01-01

    An efficient new technique is presented for rapidly determining a near-optimum pseudopotential for use in electronic energy band structure calculations. The electronic energy band structures of TiC and ZrC have been obtained and the corresponding reflectivity spectra are in fair agreement with the data. The TiC wavefunctions have been used to determine the electronic charge distribution in the (100) plane, and the results indicate that there is a net transfer of electronic charge from the titanium atom to the carbon atom. By also calculating the energy band structures of TiN and ZrN, and comparing with the carbide results, it was shown that the rigid-band model is not valid. Using the reflectivity data of Weaver, Lynch, and Olson, the electronic energy band structures of tantalum and vanadium were calculated. The vanadium density of valence states is in good agreement with Eastman's photoemission data. Furthermore, the Ta and V reflectivity spectra have been shown to be in good agreement with the data. Finally, the Fermi surfaces calculated for both Ta and V are in very good agreement with Fermi surface data

  7. High energy electron irradiation of flowable materials

    International Nuclear Information System (INIS)

    Offermann, B.P.

    1975-01-01

    In order to efficiently irradiate a flowable material with high energy electrons, a hollow body is disposed in a container for the material and the material is caused to flow in the form of a thin layer across a surface of the body from or to the interior of the container while the material flowing across the body surface is irradiated. (U.S.)

  8. Applications for Energy Recovering Free Electron Lasers

    Energy Technology Data Exchange (ETDEWEB)

    George Neil

    2007-08-01

    The availability of high-power, high-brilliance sources of tunable photons from energy-recovered Free Electron Lasers is opening up whole new fields of application of accelerators in industry. This talk will review some of the ideas that are already being put into production, and some of the newer ideas that are still under development.

  9. A Snapshot of the Danish Energy Transition

    DEFF Research Database (Denmark)

    Ropenus, Stephanie; Klinge Jacobsen, Henrik

    a deeper look at Danish energy policy in general and at the electricity sector in particular. What are the major objectives of Danish energy policy? What is the logic behind an integrated approach that encompasses all energy sectors? How has market integration evolved in the Nordic countries? How does...... the offshore wind tendering system work? What are the principles underlying grid expansion within Denmark? What types of consumer participation schemes exist? This paper aims to explore some of the lessons learned from the Danish experience. At the same time, this paper can serve as an introductory overview...

  10. Ion transition heights from topside electron density profiles

    International Nuclear Information System (INIS)

    Titheridge, J.E.

    1976-01-01

    Theoretical electron density profiles are calculated for the topside ionosphere to determine the major factors controlling the profile shape. Only the mean temperature, the vertical temperature gradient and the O + /H + ion transition height are important. Vertical proton fluxes alter the ion transition height but have no other effect on the profile shape. Diffusive equilibrium profiles including only these three effects fit observed profiles, at all latitudes, to within experimental accuracy. Values of plasma temperature, temperature gradient and ion transition height hsub(T) were determined by fitting theoretical models to 60,000 experimental profiles obtained from Alouette 1 ionograms, at latitudes of 75 0 S to 85 0 N near solar minimum. Inside the plasmasphere hsub(T) varies from about 500 km on winter nights to 850 km on summer days. Diurnal variations are caused primarily by the production and loss of O + in the ionosphere. The approximately constant winter night value of hsub(T) is close to the level for chemical equilibrium. In summer hsub(T) is always above the equilibrium level, giving a continual production of protons which travel along lines of force to aid in maintaining the conjugate winter night ionosphere. Outside the plasmasphere hsub(T) is 300 to 600 km above the equilibrium level at all times. This implies a continual near-limiting upwards flux of protons which persists down to latitudes of about 60 0 at night and 50 0 during the day. (author)

  11. Restructuring energy systems for sustainability? Energy transition policy in the Netherlands

    International Nuclear Information System (INIS)

    Kern, Florian; Smith, Adrian

    2008-01-01

    Increasingly, researchers and policy makers are confronting the challenge of restructuring energy systems into more sustainable forms. A 'transition management' model, and its adoption in the Netherlands, is attracting attention. Starting from the socio-technical multi-level theory that informs 'transition management', we analyse the 'energy transition' project carried out by the Dutch Ministry of Economic Affairs. Despite considerable achievements, their approach risks capture by the incumbent energy regime, thereby undermining original policy ambitions for structural innovation of the energy system. This experience presents generic dilemmas for transitions approaches

  12. n l -> n' l' transition rates in electron and proton - Rydberg atom collision

    Science.gov (United States)

    Vrinceanu, Daniel

    2017-04-01

    Electrons and protons drive the recombination dynamics of highly excited Rydberg atoms in cold rarefied plasmas found in astrophysical conditions such as primordial recombination or star formation in H-II clouds. It has been recognized that collisions induce both energy and angular momentum transitions in Rydberg atoms, although in different proportions, depending on the initial state, temperature and the given species considered in the collision (electron or proton). Most studies focused on one collision type at a time, under the assumption that collision types are independent or their effects are not competing. The classical Monte-Carlo trajectory simulations presented in this work calculate the rates for both energy and angular momentum transfers and show their interdependence. For example, energy transfer with small angular momentum change are more efficient for target states with initial large angular momentum. The author acknowledges support received from the National Science Foundation through a Grant for the Center for Research on Complex Networks (HRD-1137732).

  13. Electron tunneling studies of ultrathin films near the superconductor-to-insulator transition

    International Nuclear Information System (INIS)

    Valles, J.M. Jr.; Garno, J.P.

    1994-01-01

    Electron tunneling measurements on ultrathin quench-condensed films near the superconductor-to-insulator (SI) transition reveal that the superconducting state degrades with increasing normal state sheet resistance, R □ , in a manner that depends strongly on film morphology. In homogeneously disordered films, the superconducting energy gap Δ 0 decreases continuously and appears to go to zero at the SI transition. In granular films the transport properties degrade while Δ 0 remains constant. Measurements in the normal state reveal disorder enhanced e - -e - interaction corrections to the density of states. These effects are strong and depend on morphology in a manner that is consistent with their playing an important role in driving the SI transition. (orig.)

  14. Household energy transition in Hong Kong

    Energy Technology Data Exchange (ETDEWEB)

    Hills, Peter (Hong Kong Univ. (Hong Kong). Centre of Urban Planning and Environmental Management)

    1994-05-01

    A household energy survey in Hong Kong confirmed that domestic energy consumption is dominated by modern fuels. Household spending on fuels typically amounts to less than 3% of monthly income. Delivered energy use per household per month averages 1.77 GJ and per capita use 0.37 GJ. Electricity accounts for more than half of fuel expenditure and energy use. Patterns of fuel choice and use are quite consistent across income levels, although electricity use rises with higher household incomes. Many households use a combination of kerosene, gas and electricity (rice cookers) for cooking, which appears to reflect culinary practices more than fuel prices, perceived safety or availability. Electrical appliance saturation is high already, and air conditioning use is growing rapidly. Household electricity consumption may increase substantially during the 1990s as higher comfort levels lead to increased heating and cooling demand and space standards in public housing units improve. (Author)

  15. Electricity storage - A challenge for energy transition

    International Nuclear Information System (INIS)

    Bart, Jean-Baptiste; Nekrasov, Andre; Pastor, Emmanuel; Benefice, Emmanuel; Brincourt, Thierry; Cagnac, Albannie; Brisse, Annabelle; Jeandel, Elodie; Lefebvre, Thierry; Penneau, Jean-Francois; Radvanyi, Etienne; Delille, Gautier; Hinchliffe, Timothee; Lancel, Gilles; Loevenbruck, Philippe; Soler, Robert; Stevens, Philippe; Torcheux, Laurent

    2017-01-01

    After a presentation of the energetic context and of its issues, this collective publication proposes presentations of various electricity storage technologies with a distinction between direct storage, thermal storage and hydrogen storage. As far as direct storage is concerned, the following options are described: pumped energy transfer stations or PETS, compressed air energy storage or CAES, flywheels, various types of electrochemical batteries (lead, alkaline, sodium, lithium), metal air batteries, redox flow batteries, and super-capacitors. Thermal storage comprises power-to-heat and heat-to-power technologies. Hydrogen can be stored under different forms (compressed gas, liquid), in saline underground cavities, or by using water electrolysis and fuel cells. The authors propose an overview of the different services provided by energy storage to the electricity system, and discuss the main perspectives and challenges for tomorrow's storage (electric mobility, integration of renewable energies, electrification of isolated areas, scenarios of development)

  16. Electron-nuclear γ transition spectrum of a nucleus in a multicharged atomic ion

    International Nuclear Information System (INIS)

    Ivanov, L.N.; Letokhov, V.S.

    1987-01-01

    The nuclear emission of absorption spectrum of an atom possesses a set of electron satelites which are due to an alternation of the state of the electron shell. It is shown that the mechanism of formation of the satellites might be different for neutral atoms and high-charge ions. In the first case (loose electron shell) a ''shaking'' of the shell resulting from the interaction between the nucleus and γ quantum is predominant. In the second case (rigid electron shell) the mechanism involves a direct interaction between the γ quantum and electrons. The second mechanism is important in the case of dipole nuclear transitions and dominates at γ quantum energies p 2λ (λ is the nuclear transition multipole order, μ p ∼ 1/2 π is the relative proton mass and z the core mass). In the spectrum of the plasma source the electron satellites corresponding to the γ quantum emission and absorption lines are not overlapped by the Doppler contour of the γ line

  17. Electronic structure and high pressure phase transition in LaSb and CeSb

    International Nuclear Information System (INIS)

    Mathi Jaya, S.; Sanyal, S.P.

    1992-09-01

    The electronic structure and high pressure structural phase transition in cerium and lanthanum antimonides have been investigated using the tight binding LMTO method. The calculation of total energy reveals that the simple tetragonal structure is found to be stable at high pressures for both the compounds. In the case of LaSb, the calculated value of the equilibrium cell volume and the cell volume at which phase transition occurs are found to have a fairly good agreement with the experimental results. However, in the case of CeSb, the agreement is not as good as in LaSb. We also predicted the most favoured c/a value in the high pressure phase (simple tetragonal) for these compounds. Further we present the calculated results on the electronic structure of these systems at the equilibrium as well as at the reduced cell volumes. (author). 8 refs, 11 figs, 1 tab

  18. Can we Finance the Energy Transition?

    Directory of Open Access Journals (Sweden)

    Ian Johnson

    2015-05-01

    Full Text Available The energy sector is pivotal to our aspirations for a sustainable planet and yet two major challenges face policymakers worldwide. The first is to decide what set of technical choices provide the best solution to meet social, economic and environmental agendas; and the second is to decide how these choices can be financed. The bulk of new energy demand will come from the emerging economies where energy demand is expected to increase by 40% over the coming three decades and to have doubled by the middle of the century. However for a number of reasons the investment needs of the energy sector are likely to rise even faster than overall energy demand. This is due to a number of factors over and above the increase in demand and described in the paper, including, inter alia, subsidized prices; the substitution of traditional energy for modern energy; the growth in peak demand in the electricity sector; the rising costs of securing primary energy resources; and the urgent need to replace vintage capital stock (including the decommissioning of nuclear power plants, especially in the developed countries. Clean energy investment will also incur high upfront investment costs in order to reduce long-term recurrent costs (fuel and maintenance. High priority must be given to energy demand management (both to reduce energy use and to reduce energy capital and investment in upgrading of existing capital stock can provide strong and quick returns. However, the net result of the long-term demand on the energy sector is that investment needs will grow dramatically, from around US $1.6 trillion per annum to over US $2 trillion per annum. The financial challenge is considerable. A level playing field is required that encourages greater competition of technology choice on the basis of correct pricing signals. It will require changes in subsidy policies in order to release finance and to encourage efficient investment; adherence to least-cost planning and investment

  19. Electronic self-organization in layered transition metal dichalcogenides

    Energy Technology Data Exchange (ETDEWEB)

    Ritschel, Tobias

    2015-10-30

    The interplay between different self-organized electronically ordered states and their relation to unconventional electronic properties like superconductivity constitutes one of the most exciting challenges of modern condensed matter physics. In the present thesis this issue is thoroughly investigated for the prototypical layered material 1T-TaS{sub 2} both experimentally and theoretically. At first the static charge density wave order in 1T-TaS{sub 2} is investigated as a function of pressure and temperature by means of X-ray diffraction. These data indeed reveal that the superconductivity in this material coexists with an inhomogeneous charge density wave on a macroscopic scale in real space. This result is fundamentally different from a previously proposed separation of superconducting and insulating regions in real space. Furthermore, the X-ray diffraction data uncover the important role of interlayer correlations in 1T-TaS{sub 2}. Based on the detailed insights into the charge density wave structure obtained by the X-ray diffraction experiments, density functional theory models are deduced in order to describe the electronic structure of 1T-TaS{sub 2} in the second part of this thesis. As opposed to most previous studies, these calculations take the three-dimensional character of the charge density wave into account. Indeed the electronic structure calculations uncover complex orbital textures, which are interwoven with the charge density wave order and cause dramatic differences in the electronic structure depending on the alignment of the orbitals between neighboring layers. Furthermore, it is demonstrated that these orbital-mediated effects provide a route to drive semiconductor-to-metal transitions with technologically pertinent gaps and on ultrafast timescales. These results are particularly relevant for the ongoing development of novel, miniaturized and ultrafast devices based on layered transition metal dichalcogenides. The discovery of orbital textures

  20. Negawatt manifesto - Making energy transition a success; Manifeste Negawatt - Reussir la transition energetique

    Energy Technology Data Exchange (ETDEWEB)

    Salomon, Thierry; Jedliczka, Marc; Marignac, Yves; Hessel, Stephane; Lovins, Amory

    2012-01-19

    For ten years, the Negawatt association has taken a fresh look at our ways of consuming and producing energy. After the realisation of its 2011 scenario, the association has wished to complete this work with a reflexion full of ideas and operational measures and addressed to all citizens and to decision-makers. This manifesto describes with pedagogy and lucidity a possible and desirable path to get out of our energy and climate crises. Contents: 1 - Energy in crisis; 2 - Energy in its all forms; 3 - From the approach to the scenario: preparing the energy transition; 4 - Buildings and energy transition; 5 - Key-sectors of the transition: transports, industry and agriculture; 6 - Advent of renewable energies; 7 - From the nuclear twilight to the renewable dawn; 8 - Costs and benefits of the energy transition; 9 - The 'true value' of energy; 10 - From the status time to the action one. A series of 26 graphs summarizes the Negawatt approach. (J.S.)

  1. Working on Energy Transition in the Netherlands. Report of the Internet Energy Debate

    International Nuclear Information System (INIS)

    Braat, F.W.; Bruinsma, O.

    2010-12-01

    The aim of the debate was to gain insight (highlights and gaps) in the Dutch approach to energy transition and to get a feel for the sense of urgency. The results of the internet debate address the problems and (Dutch) challenges as could be deduced from the contributions and reactions. We suggest that the following four topics are relevant to keep in mind when participating in co-ordinated activities in the Netherlands such as the 'transition platforms' as initiated by the Dutch ministries involved: (1) The definition of energy transition - transform the community from the bottom up; (2) The goal of energy transition - develop systems to replace systems; (3) The organisation of energy transition - articulate user requirements and conditions; (4) Energy transition systems thinking - direct support also at nascent business models. [nl

  2. Vertical coupling and transition energies in multilayer InAs/GaAs quantum-dot structures

    Science.gov (United States)

    Taddei, S.; Colocci, M.; Vinattieri, A.; Bogani, F.; Franchi, S.; Frigeri, P.; Lazzarini, L.; Salviati, G.

    2000-10-01

    Vertically ordered quantum dots in multilayer InAs/GaAs structures have attracted large interest in recent years for device application as light emitters. Contradictory claims on the dependence of the fundamental transition energy on the interlayer separation and number of dot layers have been reported in the literature. We show that either a blueshift or a redshift of the fundamental transition energy can be observed in different coupling conditions and straightforwardly explained by including strain, indium segregation, and electron-hole Coulomb interaction, in good agreement with experimental results.

  3. Theoretical Study of Energy Levels and Transition Probabilities of Boron Atom

    Science.gov (United States)

    Tian Yi, Zhang; Neng Wu, Zheng

    2009-08-01

    Full Text PDF Though the electrons configuration for boron atom is simple and boron atom has long been of interest for many researchers, the theoretical studies for properties of BI are not systematic, there are only few results reported on energy levels of high excited states of boron, and transition measurements are generally restricted to transitions involving ground states and low excited states without considering fine structure effects, provided only multiplet results, values for transitions between high excited states are seldom performed. In this article, by using the scheme of the weakest bound electron potential model theory calculations for energy levels of five series are performed and with the same method we give the transition probabilities between excited states with considering fine structure effects. The comprehensive set of calculations attempted in this paper could be of some value to workers in the field because of the lack of published calculations for the BI systems. The perturbations coming from foreign perturbers are taken into account in studying the energy levels. Good agreement between our results and the accepted values taken from NIST has been obtained. We also reported some values of energy levels and transition probabilities not existing on the NIST data bases.

  4. Energy transition: how is Germany doing?

    International Nuclear Information System (INIS)

    Boulanger, Vincent

    2015-01-01

    In this book the author comments and discusses the content, successes and failures, uncertainties and consequences of the new German energy policy, Energiewende. The objective is to reach 80 to 95 per cent of reduction of greenhouse gas emissions by 2050 while phasing out nuclear. The author denies some statements about this policy. Some say that coal will replace nuclear as in fact renewable electricity production more than compensates the reduction of nuclear electricity production. Others say that Germany will have to import French nuclear electricity as in fact France must import German electricity in case of peak consumptions. Others say that German electricity became more expensive: it's true but it is in fact compensated by much higher energy savings. Remaining issues are the financing of nuclear plant dismantling and of nuclear waste management, the organisation of a decentralised production network, and the passage to renewable energies in the heating and transport sectors

  5. Electron-ion recombination at low energy

    International Nuclear Information System (INIS)

    Andersen, L.H.

    1993-01-01

    The work is based on results obtained with a merged-beams experiment. A beam of electronics with a well characterized density and energy distribution was merged with a fast, monoenergetic ion beam. Results have been obtained for radiative recombination and dielectronic recombination at low relative energies (0 to ∼70eV). The obtained energy resolution was improved by about a factor of 30. High vacuum technology was used to suppress interactions with electrons from the environments. The velocity distribution of the electron beam was determined. State-selective dielectronic-recombination measurements were performable. Recombination processes were studied. The theoretical background for radiative recombination and Kramers' theory are reviewed. The quantum mechanical result and its relation to the semiclassical theory is discussed. Radiative recombination was also measured with several different non-bare ions, and the applicability of the semiclassical theory to non-bare ions was investigated. The use of an effective charge is discussed. For dielectronic recombination, the standard theoretical approach in the isolated resonance and independent-processes approximation is debated. The applicability of this method was tested. The theory was able to reproduce most of the experimental data except when the recombination process was sensitive to couplings between different electronic configurations. The influence of external perturbing electrostatic fields is discussed. (AB) (31 refs.)

  6. Energy efficiency. Lever for the German energy transition

    International Nuclear Information System (INIS)

    Persem, Melanie; Roesner, Sven

    2014-05-01

    This document provides some key data on energy consumption in housing and public buildings, indicates the national German objectives in terms of reduction of energy consumption, of reduction of electricity consumption, of energy efficiency, and of evolution of energy consumption in housing and public buildings and in the transport sector. It gives some data related to energy saving and achievements: energy efficiency of the German economy, improvements in housing energy efficiency and insulation, financial support for low income households, reduction of energy consumption within small-medium enterprises, the public sector, the data processing sector and public lighting, and energy saving potential by renewal of public buildings. It indicates the main measures and arrangements: information, support programs for enterprises, local communities and individuals. A graph illustrates a comparison of shares of household power consumption in France and in Germany

  7. The German energy transition. Design, implementeation, cost and lessons

    Energy Technology Data Exchange (ETDEWEB)

    Unnerstall, Thomas

    2017-07-01

    The book presents a comprehensive and systematic account of the concept, the current status and the costs of the German energy transition: the Energiewende. Written by an insider who has been working in the German energy industry for over 20 years, it follows a strictly non-political, neutral approach and clearly outlines the most relevant facts and figures. In particular, it describes the main impacts of the Energiewende on the German power system and Germany's national economy. Furthermore, it addresses questions that are of global interest with respect to energy transitions, such as the cost to the national economy, the financial burden on private households and companies and the actual effects on CO{sub 2} emissions. The book also discusses what could have been done better in terms of planning and implementing the Energiewende, and identifies important lessons for other countries that are considering a similar energy transition.

  8. The German energy transition. Design, implementeation, cost and lessons

    International Nuclear Information System (INIS)

    Unnerstall, Thomas

    2017-01-01

    The book presents a comprehensive and systematic account of the concept, the current status and the costs of the German energy transition: the Energiewende. Written by an insider who has been working in the German energy industry for over 20 years, it follows a strictly non-political, neutral approach and clearly outlines the most relevant facts and figures. In particular, it describes the main impacts of the Energiewende on the German power system and Germany's national economy. Furthermore, it addresses questions that are of global interest with respect to energy transitions, such as the cost to the national economy, the financial burden on private households and companies and the actual effects on CO 2 emissions. The book also discusses what could have been done better in terms of planning and implementing the Energiewende, and identifies important lessons for other countries that are considering a similar energy transition.

  9. Energy exchange dynamics across L-H transitions in NSTX

    Science.gov (United States)

    Diallo, A.; Banerjee, S.; Zweben, S. J.; Stoltzfus-Dueck, T.

    2017-06-01

    We studied the energy exchange dynamics across the low-to-high-confinement (L-H) transition in NSTX discharges using the gas-puff imaging (GPI) diagnostic. The investigation focused on the energy exchange between flows and turbulence to help clarify the mechanism of the L-H transition. We applied this study to three types of heating schemes, including a total of 17 shots from the NSTX 2010 campaign run. Results show that the edge fluctuation characteristics (fluctuation levels, radial and poloidal correlation lengths) measured using GPI do not vary just prior to the H-mode transition, but change after the transition. Using a velocimetry approach (orthogonal-dynamics programming), velocity fields of a 24× 30 cm GPI view during the L-H transition were obtained with good spatial (˜1 cm) and temporal (˜2.5 μs) resolutions. Analysis using these velocity fields shows that the production term is systematically negative just prior to the L-H transition, indicating a transfer from mean flows to turbulence, which is inconsistent with the predator-prey paradigm. Moreover, the inferred absolute value of the production term is two orders of magnitude too small to explain the observed rapid L-H transition. These discrepancies are further reinforced by consideration of the ratio between the kinetic energy in the mean flow to the thermal free energy, which is estimated to be much less than 1, suggesting again that the turbulence depletion mechanism may not play an important role in the transition to the H-mode. Although the Reynolds work therefore appears to be too small to directly deplete the turbulent free energy reservoir, order-of-magnitude analysis shows that the Reynolds stress may still make a non-negligible contribution to the observed poloidal flows.

  10. Energy levels and transition probabilities for Fe XXV ions

    Energy Technology Data Exchange (ETDEWEB)

    Norrington, P.H.; Kingston, A.E.; Boone, A.W. [Department of Applied Maths and Theoretical Physics, Queen' s University, Belfast BT7 1NN (United Kingdom)

    2000-05-14

    The energy levels of the 1s{sup 2}, 1s2l and 1s3l states of helium-like iron Fe XXV have been calculated using two sets of configuration-interaction wavefunctions. One set of wavefunctions was generated using the fully relativistic GRASP code and the other was obtained using CIV3, in which relativistic effects are introduced using the Breit-Pauli approximation. For transitions from the ground state to the n=2 and 3 states and for transitions between the n=2 and 3 states, the calculated excitation energies obtained by these two independent methods are in very good agreement and there is good agreement between these results and recent theoretical and experimental results. However, there is considerable disagreement between the various excitation energies for the transitions among the n=2 and also among the n=3 states. The two sets of wavefunctions are also used to calculate the E1, E2, M1 and M2 transition probabilities between all of the 1s{sup 2}, 1s2l and 1s3l states of helium-like iron Fe XXV. The results from the two calculations are found to be similar and to compare very well with other recent results for {delta}n=1 or 2 transitions. For {delta}n=0 transitions the agreement is much less satisfactory; this is mainly due to differences in the excitation energies. (author)

  11. Can low energy electrons affect high energy physics accelerators?

    CERN Document Server

    Cimino, R; Furman, M A; Pivi, M; Ruggiero, F; Rumolo, Giovanni; Zimmermann, Frank

    2004-01-01

    The properties of the electrons participating in the build up of an electron cloud (EC) inside the beam-pipe have become an increasingly important issue for present and future accelerators whose performance may be limited by this effect. The EC formation and evolution are determined by the wall-surface properties of the accelerator vacuum chamber. Thus, the accurate modeling of these surface properties is an indispensible input to simulation codes aimed at the correct prediction of build-up thresholds, electron-induced instability or EC heat load. In this letter, we present the results of surface measurements performed on a prototype of the beam screen adopted for the Large Hadron Collider (LHC), which presently is under construction at CERN. We have measured the total secondary electron yield (SEY) as well as the related energy distribution curves (EDC) of the secondary electrons as a function of incident electron energy. Attention has been paid, for the first time in this context, to the probability at whic...

  12. An energy monitor for electron accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Geske, G. (Friedrich-Schiller-Universitaet, Jena (German Democratic Republic). Klinik und Poliklinik des Bereiches Medizin)

    1990-09-01

    A monitor useful for checks of the energy selector scale of medical electron accelerators was developed and tested. It consists of a linear array of flat ionization chambers sandwiched between absorber plates of low-Z material. The first chamber at the electron beam entrance may be used to produce a reference signal S{sub r}, if not another suitable reference signal is taken. The following chambers are electrically connected and deliver the measuring signal S{sub m}. A clinical dosimeter can be used for recording current or charge. The energy-dependent electron range parameters R{sub p}, R{sub 50} and R{sub 80} in water vary as linear functions of the ratio reference singal/measuring signal. The best linear fit was obtained for the half value layer R{sub 50}. Three types of the energy monitor are described, and experimental results obtained with a linear accelerator and a betatron between 5 and 25 MeV are reported. Uncertainties for checks of R{sub 50} with a calibrated energy monitor were not larger than 1 to 2 mm. Theoretical considerations by a computer model support these results. (orig./HP).

  13. An energy monitor for electron accelerators

    International Nuclear Information System (INIS)

    Geske, G.

    1990-01-01

    A monitor useful for checks of the energy selector scale of medical electron accelerators was developed and tested. It consists of a linear array of flat ionization chambers sandwiched between absorber plates of low-Z material. The first chamber at the electron beam entrance may be used to produce a reference signal S r , if not another suitable reference signal is taken. The following chambers are electrically connected and deliver the measuring signal S m . A clinical dosimeter can be used for recording current or charge. The energy-dependent electron range parameters R p , R 50 and R 80 in water vary as linear functions of the ratio reference singal/measuring signal. The best linear fit was obtained for the half value layer R 50 . Three types of the energy monitor are described, and experimental results obtained with a linear accelerator and a betatron between 5 and 25 MeV are reported. Uncertainties for checks of R 50 with a calibrated energy monitor were not larger than 1 to 2 mm. Theoretical considerations by a computer model support these results. (orig./HP) [de

  14. Low energy electron transport in furfural

    Science.gov (United States)

    Lozano, Ana I.; Krupa, Kateryna; Ferreira da Silva, Filipe; Limão-Vieira, Paulo; Blanco, Francisco; Muñoz, Antonio; Jones, Darryl B.; Brunger, Michael J.; García, Gustavo

    2017-09-01

    We report on an initial investigation into the transport of electrons through a gas cell containing 1 mTorr of gaseous furfural. Results from our Monte Carlo simulation are implicitly checked against those from a corresponding electron transmission measurement. To enable this simulation a self-consistent cross section data base was constructed. This data base is benchmarked through new total cross section measurements which are also described here. In addition, again to facilitate the simulation, our preferred energy loss distribution function is presented and discussed.

  15. Year 2 of Germany's Energy Transition

    International Nuclear Information System (INIS)

    Cruciani, Michel

    2013-01-01

    After a decade characterised by the take-off of renewable energies, Germany decided in 2010 to make them the top priority. At the same time, it decided to make exemplary efforts in terms of energy efficiency and the reduction of greenhouse gases. The audacious nature of this policy was strengthened by the 'turn' taken in 2011 to give up nuclear energy in the wake of the Fukushima accident. Given the initial results for 2012, Germany seems to be on target for reaching its national objective, of 18% renewable energy within total consumption by 2020. Germany is also well placed to reduce its planned cut in electricity consumption of 10%. The country will also meet its commitments, both international and European, concerning greenhouse gas emissions. In contrast, recent trends suggest it will be increasingly difficult for Germany to meet its own, domestic goal of cutting emissions by 40%, by 2020. Furthermore, it is hard to see how Germany will be able to bring down total energy consumption by 20% by 2020 (from 2008 levels), or increase the share of renewables in electricity production above 35%. Success with this latter objective is largely dependent on reinforcing networks, both for transmission over long distances and for local distribution. It is not sure that the delays accumulated in both areas will be made up for by 2020, despite the rapid legislative adjustments that have already been made. By favouring intermittent energy sources - wind and solar power - Germany also faces problems of managing frequent production fluctuations. The long term solution to this lies in storing electricity. However, despite the considerable efforts in research and development, the technologies necessary for this will doubtless not be available on a large scale before the end of the present decade. These efforts could nevertheless provide German industry with interesting advantages in sectors of high potential, such as electric vehicles. Measures to promote renewable energies are

  16. The law on energy transition for a green growth

    International Nuclear Information System (INIS)

    Signoret, Stephane

    2015-01-01

    This article presents the main issues addressed by the French law on energy transition for a green growth. Thus, it evokes its main objectives and how they can be reached (notably through a control of energy demand, a wider carbon share in taxes), gives an overview of measures related to building renovation, to the development of clean transports (priority to less polluting transport modes, energy efficiency and renewable energy in transports, reduction of greenhouse gas and pollutant emissions, plan for air quality), to the struggle against wastage and to the promotion of circular economy, to the promotion of renewable energies, to the reinforcement of nuclear safety and citizen information, to the simplification and clarification of procedures, to making citizens, enterprises and State able to act together (through governance tools, the steering of electricity production, energy transition in territories, specific measures for non-interconnected areas)

  17. Scenarios for a urban energy transition. Actors, regulations, technologies

    International Nuclear Information System (INIS)

    Debizet, Gilles; Blanco, Sylvie; Buclet, Nicolas; Forest, Fabrice; Gauthier, Caroline; La Branche, Stephane; Menanteau, Philippe; Schneuwly, Patrice; Tabourdeau, Antoine

    2016-01-01

    Cities concentrate populations, consumptions, levers of actions, and are places of various experiments for energy transition. This book aims at giving an overview of possible scenarios of development of renewable energies in urban context. It is based on interviews of actors of the energy, building and urban planning sectors by researchers in town planning, management, technology, political and economic sciences. The authors examine what would occur if large companies would manage entire quarters, if local authorities would supervise production and supply, if the State would take control of all fields of action again, or if consumer cooperatives would exchange energy and pool productions. In its different chapters, the book presents four scenarios of energy coordination in urban context by 2040, discuss energy transition in urban spaces, discuss the perspectives of evolution towards more autonomous cities and quarters from an energetic point of view, and discuss business models and urban energetic innovations

  18. Converged G W quasiparticle energies for transition metal oxide perovskites

    Science.gov (United States)

    Ergönenc, Zeynep; Kim, Bongjae; Liu, Peitao; Kresse, Georg; Franchini, Cesare

    2018-02-01

    The ab initio calculation of quasiparticle (QP) energies is a technically and computationally challenging problem. In condensed matter physics, the most widely used approach to determine QP energies is the G W approximation. Although the G W method has been widely applied to many typical semiconductors and insulators, its application to more complex compounds such as transition metal oxide perovskites has been comparatively rare, and its proper use is not well established from a technical point of view. In this work, we have applied the single-shot G0W0 method to a representative set of transition metal oxide perovskites including 3 d (SrTiO3, LaScO3, SrMnO3, LaTiO3, LaVO3, LaCrO3, LaMnO3, and LaFeO3), 4 d (SrZrO3, SrTcO3, and Ca2RuO4 ), and 5 d (SrHfO3, KTaO3, and NaOsO3) compounds with different electronic configurations, magnetic orderings, structural characteristics, and band gaps ranging from 0.1 to 6.1 eV. We discuss the proper procedure to obtain well-converged QP energies and accurate band gaps within single-shot G0W0 by comparing the conventional approach based on an incremental variation of a specific set of parameters (number of bands, energy cutoff for the plane-wave expansion and number of k points) and the basis-set extrapolation scheme [J. Klimeš et al., Phys. Rev. B 90, 075125 (2014), 10.1103/PhysRevB.90.075125]. Although the conventional scheme is not supported by a formal proof of convergence, for most cases it delivers QP energies in reasonably good agreement with those obtained by the basis-set correction procedure and it is by construction more useful for calculating band structures. In addition, we have inspected the difference between the adoption of norm-conserving and ultrasoft potentials in G W calculations and found that the norm violation for the d shell can lead to less accurate results in particular for charge-transfer systems and late transition metals. A minimal statistical analysis indicates that the correlation of the G W data

  19. High Energy Electron Detectors on Sphinx

    Science.gov (United States)

    Thompson, J. R.; Porte, A.; Zucchini, F.; Calamy, H.; Auriel, G.; Coleman, P. L.; Bayol, F.; Lalle, B.; Krishnan, M.; Wilson, K.

    2008-11-01

    Z-pinch plasma radiation sources are used to dose test objects with K-shell (˜1-4keV) x-rays. The implosion physics can produce high energy electrons (> 50keV), which could distort interpretation of the soft x-ray effects. We describe the design and implementation of a diagnostic suite to characterize the electron environment of Al wire and Ar gas puff z-pinches on Sphinx. The design used ITS calculations to model detector response to both soft x-rays and electrons and help set upper bounds to the spurious electron flux. Strategies to discriminate between the known soft x-ray emission and the suspected electron flux will be discussed. H.Calamy et al, ``Use of microsecond current prepulse for dramatic improvements of wire array Z-pinch implosion,'' Phys Plasmas 15, 012701 (2008) J.A.Halbleib et al, ``ITS: the integrated TIGER series of electron/photon transport codes-Version 3.0,'' IEEE Trans on Nuclear Sci, 39, 1025 (1992)

  20. Energy and environment: transitions in Eastern Europe

    International Nuclear Information System (INIS)

    1992-01-01

    The proceedings contain 91 abstracts of contributions delivered as lectures and 47 abstracts of contributions presented as posters. Out of them, 4 have been inputted in INIS. They deal with air pollution in Turkey, with impacts of open pit mines in North Bohemia on the quality of air, environmental impacts of the thermal power plant at Drobeta Turnu Severin in Romania, and with Latvia's environmental problems associated with energy supplies. (M.D.)

  1. Local energy equation for two-electron atoms and relation between kinetic energy and electron densities

    International Nuclear Information System (INIS)

    March, N.H.

    2002-08-01

    In early work, Dawson and March [J. Chem. Phys. 81, 5850 (1984)] proposed a local energy method for treating both Hartree-Fock and correlated electron theory. Here, an exactly solvable model two-electron atom with pure harmonic interactions is treated in its ground state in the above context. A functional relation between the kinetic energy density t(r) at the origin r=0 and the electron density p(r) at the same point then emerges. The same approach is applied to the Hookean atom; in which the two electrons repel with Coulombic energy e 2 /r 12 , with r 12 the interelectronic separation, but are still harmonically confined. Again the kinetic energy density t(r) is the focal point, but now generalization away from r=0 is also effected. Finally, brief comments are added about He-like atomic ions in the limit of large atomic number. (author)

  2. High-pressure electron-resonance studies of electronic, magnetic, and structural phase transitions. Progress report

    International Nuclear Information System (INIS)

    Pifer, J.H.; Croft, M.C.

    1983-01-01

    Research is described in development of a high-pressure electron-resonance probe capable of operating down to 1.5 0 K temperatures. The apparatus has been used to measure the EPR of a sample of DPPH at room temperature and zero pressure. EPR has been used to measure valence field instabilities in alloy systems. Studies have been done on metal-insulator transitions at high pressure, and are briefly described

  3. Energy transition: how is Germany doing?

    International Nuclear Information System (INIS)

    Boulanger, Vincent

    2017-04-01

    This book is an updated edition of the previous version from 2015. In this book the author comments and discusses the content, successes and failures, uncertainties and consequences of the new German energy policy, Energiewende. The objective is to reach 80 to 95 per cent of reduction of greenhouse gas emissions by 2050 while phasing out nuclear. The author denies some statements about this policy. Some say that coal will replace nuclear as in fact renewable electricity production more than compensates the reduction of nuclear electricity production. Others say that Germany will have to import French nuclear electricity as in fact France must import German electricity in case of peak consumptions. Others say that German electricity became more expensive: it's true but it is in fact compensated by much higher energy savings. Remaining issues are the financing of nuclear plant dismantling and of nuclear waste management, the organisation of a decentralised production network, and the passage to renewable energies in the heating and transport sectors

  4. Suppression of the Transit -Time Instability in Large-Area Electron Beam Diodes

    Science.gov (United States)

    Myers, Matthew C.; Friedman, Moshe; Swanekamp, Stephen B.; Chan, Lop-Yung; Ludeking, Larry; Sethian, John D.

    2002-12-01

    Experiment, theory, and simulation have shown that large-area electron-beam diodes are susceptible to the transit-time instability. The instability modulates the electron beam spatially and temporally, producing a wide spread in electron energy and momentum distributions. The result is gross inefficiency in beam generation and propagation. Simulations indicate that a periodic, slotted cathode structure that is loaded with resistive elements may be used to eliminate the instability. Such a cathode has been fielded on one of the two opposing 60 cm × 200 cm diodes on the NIKE KrF laser at the Naval Research Laboratory. These diodes typically deliver 600 kV, 500 kA, 250 ns electron beams to the laser cell in an external magnetic field of 0.2 T. We conclude that the slotted cathode suppressed the transit-time instability such that the RF power was reduced by a factor of 9 and that electron transmission efficiency into the laser gas was improved by more than 50%.

  5. Suppression of the transit-time instability in large-area electron beam diodes

    International Nuclear Information System (INIS)

    Myers, Matthew C.; Friedman, Moshe; Sethian, John D.; Swanekamp, Stephen B.; Chan, L.-Y.; Ludeking, Larry

    2002-01-01

    Experiment, theory, and simulation have shown that large-area electron-beam diodes are susceptible to the transit-time instability. The instability modulates the electron beam spatially and temporally, producing a wide spread in electron energy and momentum distributions. The result is gross inefficiency in beam generation and propagation. Simulations indicate that a periodic, slotted cathode structure that is loaded with resistive elements may be used to eliminate the instability. Such a cathode has been fielded on one of the two opposing 60 cm x 200 cm diodes on the NIKE KrF laser at the Naval Research Laboratory. These diodes typically deliver 600 kV, 500 kA, 250 ns electron beams to the laser cell in an external magnetic field of 0.2 T. We conclude that the slotted cathode suppressed the transit-time instability such that the RF power was reduced by a factor of 9 and that electron transmission efficiency into the laser gas was improved by more than 50%

  6. Transition-energy crossing with a γt-jump

    International Nuclear Information System (INIS)

    Wei, Jie; Peggs, S.

    1994-01-01

    Expressions for the minimum size and speed of a transition-energy (γ t -) jump needed to diminish the chromatic non-linear effect, the self-field mismatch, and the microwave instabilities in the Relativistic Heavy Ion Collider (RHIC) are obtained. A γ t -jump of 0.8 units is needed to be performed within 60 ms in order to achieve a ''clean'' transition crossing

  7. Characteristics of the Mott transition and electronic states of high-temperature cuprate superconductors from the perspective of the Hubbard model

    Science.gov (United States)

    Kohno, Masanori

    2018-04-01

    A fundamental issue of the Mott transition is how electrons behaving as single particles carrying spin and charge in a metal change into those exhibiting separated spin and charge excitations (low-energy spin excitation and high-energy charge excitation) in a Mott insulator. This issue has attracted considerable attention particularly in relation to high-temperature cuprate superconductors, which exhibit electronic states near the Mott transition that are difficult to explain in conventional pictures. Here, from a new viewpoint of the Mott transition based on analyses of the Hubbard model, we review anomalous features observed in high-temperature cuprate superconductors near the Mott transition.

  8. Buenos Aires: The Unattainable Energy Transition of a Fragmented Metropolis

    International Nuclear Information System (INIS)

    Prevot-Schapira, Marie-France; Velut, Sebastien

    2013-01-01

    The case of Buenos Aires (13 million inhabitants) exemplifies the evolution of energy supply and distribution in a developing metropolis characterized by the growth of consumption, spatial extension and social contrasts. After the 2001 economic and political crisis, the energy sectors underwent a major reorganization. For the city this meant growing state intervention in energy supply, private firms and the fixing of energy prices. The resulting evolution does not meet the criteria of energy transition as conceived in Europe, but it highlights the weight of the federal government upon a fragmented metropolis where local actors struggle to find their own spaces of action

  9. Energy Transformation in Molecular Electronic Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kasha, Michael

    1999-05-17

    This laboratory has developed many new ideas and methods in the electronic spectroscopy of molecules. This report covers the contract period 1993-1995. A number of the projects were completed in 1996, and those papers are included in the report. The DOE contract was terminated at the end of 1995 owing to a reorganizational change eliminating nationally the projects under the Office of Health and Environmental Research, U. S. Department of Energy.

  10. Energy transition in federalism; Energiewende im Foederalismus

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Thorsten; Kahl, Hartmut (eds.)

    2015-07-01

    The conference transcript assemble the presentations of the 10th Wuerzburg discussions for environmental energy law. The contributions discuss the political development objectives of the Federal Government and Federal States as well as the coordination tasks between the different political levels, inter alia, of constitutional and European law perspective. [German] Der Tagungsband versammelt die Vortraege der 10. Wuerzburger Gespraeche zum Umweltenergierecht. Die Beitraege eroertern die politischen Ausbauziele des Bundes und der Laender sowie die Koordinierungsaufgaben zwischen den verschiedenen Politikebenen u.a. aus verfassungs- und europarechtlicher Perspektive.

  11. Research for the energy transition. The organization of the energy systems; Forschung fuer die Energiewende. Die Gestaltung des Energiesystems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-03-15

    The volume on research for the energy transition includes contributions to the FVEE annual meeting 2016 concerning the following issues: status and perspectives of the energy transition, key technologies for the energy transition, political boundary conditions, development trends in photovoltaics, components for the energy supply (wind energy, hydrogen technologies, smart bioenergy concept, contribution of the geosphere), grids and storage systems for the energy transition, research network renewable energies.

  12. Motion for a resolution on energy transition - Nr 2042

    International Nuclear Information System (INIS)

    Pancher, Bertrand; Jego, Yves; Leroy, Maurice; Tuaiva, Jean-Paul; Tahuaitu, Jonas; Favennec, Yannick; Zumkeller, Michel; Morin, Herve

    2014-01-01

    This motion for a resolution on energy transition proposes a framework which integrates energy management, the development of renewable energies in France, an adapted taxation, and a clear industrial project for future energies. This framework must lead to the introduction of five-year and constraining budgets of reduction of greenhouse gas emissions. Thus, the articles of this motion address various topics: definition of national objectives of reduction of emissions, renewal of buildings, implementation of a tool similar to the British Climate Change Act, implementation of a new energy governance, launching of large industrial projects, European integration of the energy market, importance of energy efficiency and of consumption management, a review of the subsidy system for renewable energies, pollution taxation and reform of the ETS, limitation of the share of nuclear energy, introduction of a carbon tax at the border of the EU, promotion of rail freight transport, and so on

  13. Hot-electron-mediated desorption rates calculated from excited-state potential energy surfaces

    DEFF Research Database (Denmark)

    Olsen, Thomas; Gavnholt, Jeppe; Schiøtz, Jakob

    2009-01-01

    We present a model for desorption induced by (multiple) electronic transitions [DIET (DIMET)] based on potential energy surfaces calculated with the delta self-consistent field extension of density-functional theory. We calculate potential energy surfaces of CO and NO molecules adsorbed on variou...

  14. The great debate: Energy transition, it's us

    International Nuclear Information System (INIS)

    2016-09-01

    Published by authorities of the Nantes metropolitan area, this document first comprises a report in two parts. The first one presents a general approach to energy transition, some definitions, an overview of challenges and stakes, and of action levers. It also describes the national and local contexts with their key figures. The second part addresses three issues of the debate on energy transition: which transition for life styles? Which landscapes and new usages? Which citizen and local appropriation of energy from production to consumption? Which innovation opportunities and jobs? A second document is the final report produced by the debate commission. It proposes an assessment of the participation dynamics, an analysis of citizen contributions on the four above-mentioned issues, and recommendations made by the commission declined in 60 actions. Other documents are also provided: periodic publications with various contributions on the various related issues

  15. The role of nuclear energy in times of energy transition

    International Nuclear Information System (INIS)

    2012-01-01

    Since the reactor catastrophe in Fukushima, the risk of nuclear power has once again become more evident to the public and has also led to a rethinking of politics in Europe. Slogans like ''Nuclear Power, No Thanks!'', ''Get Out of Euratom'' are making more and more the rounds. The phase-out of nuclear energy is the topic that is increasingly provoking people to think. But how should one handle this? What role will nuclear energy play in a distant future? Central factors such as the economic viability of renewable energy sources and the environmental and social compatibility of production and distribution must be taken into account, while at the same time the reduction of pollutants and greenhouse gases must continue. If this is done without nuclear energy, is the rapid abandonment of nuclear energy even necessary or does nuclear energy generation have to be used as a temporary solution? (roessner)

  16. Determining the static electronic and vibrational energy correlations via two-dimensional electronic-vibrational spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Hui; Lewis, Nicholas H. C.; Oliver, Thomas A. A.; Fleming, Graham R., E-mail: grfleming@lbl.gov [Department of Chemistry, University of California, Berkeley, California 94720 (United States); Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, Californial 94720 (United States); Kavli Energy NanoSciences Institute at Berkeley, Berkeley, California 94720 (United States)

    2015-05-07

    Changes in the electronic structure of pigments in protein environments and of polar molecules in solution inevitably induce a re-adaption of molecular nuclear structure. Both changes of electronic and vibrational energies can be probed with visible or infrared lasers, such as two-dimensional electronic spectroscopy or vibrational spectroscopy. The extent to which the two changes are correlated remains elusive. The recent demonstration of two-dimensional electronic-vibrational (2DEV) spectroscopy potentially enables a direct measurement of this correlation experimentally. However, it has hitherto been unclear how to characterize the correlation from the spectra. In this paper, we present a theoretical formalism to demonstrate the slope of the nodal line between the excited state absorption and ground state bleach peaks in the spectra as a characterization of the correlation between electronic and vibrational transition energies. We also show the dynamics of the nodal line slope is correlated to the vibrational spectral dynamics. Additionally, we demonstrate the fundamental 2DEV spectral line-shape of a monomer with newly developed response functions.

  17. Quantum-classical transition in the electron dynamics of thin metal films

    Energy Technology Data Exchange (ETDEWEB)

    Jasiak, R; Manfredi, G; Hervieux, P-A [Institut de Physique et Chimie des Materiaux, CNRS and Universite de Strasbourg, BP 43, F-67034 Strasbourg (France); Haefele, M [INRIA Nancy Grand-Est and Institut de Recherche en Mathematiques Avancees, 7 rue Rene Descartes, F-67084 Strasbourg (France)], E-mail: Giovanni.Manfredi@ipcms.u-strasbg.fr

    2009-06-15

    The quantum electrons dynamics in a thin metal film is studied numerically using the self-consistent Wigner-Poisson equations. The initial equilibrium is computed from the Kohn-Sham equations at finite temperature, and then mapped into the phase-space Wigner function. The time-dependent results are compared systematically with those obtained previously with a classical approach (Vlasov-Poisson equations). It is found that, for large excitations, the quantum and classical dynamics display the same low-frequency oscillations due to ballistic electrons bouncing back and forth on the film surfaces. However, below a certain excitation energy (roughly corresponding to one quantum of plasmon energy {Dirac_h}{omega}{sub p}), the quantum and classical results diverge, and the ballistic oscillations are no longer observed. These results provide an example of a quantum-classical transition that may be observed with current pump-probe experiments on thin metal films.

  18. Quantum-classical transition in the electron dynamics of thin metal films

    International Nuclear Information System (INIS)

    Jasiak, R; Manfredi, G; Hervieux, P-A; Haefele, M

    2009-01-01

    The quantum electrons dynamics in a thin metal film is studied numerically using the self-consistent Wigner-Poisson equations. The initial equilibrium is computed from the Kohn-Sham equations at finite temperature, and then mapped into the phase-space Wigner function. The time-dependent results are compared systematically with those obtained previously with a classical approach (Vlasov-Poisson equations). It is found that, for large excitations, the quantum and classical dynamics display the same low-frequency oscillations due to ballistic electrons bouncing back and forth on the film surfaces. However, below a certain excitation energy (roughly corresponding to one quantum of plasmon energy ℎω p ), the quantum and classical results diverge, and the ballistic oscillations are no longer observed. These results provide an example of a quantum-classical transition that may be observed with current pump-probe experiments on thin metal films.

  19. Energy Efficiency and Urban Renewal in the Economies in Transition

    International Nuclear Information System (INIS)

    Brendow, K.

    1997-01-01

    The Paper notes the importance of energy consumption in agglomerations (65-70% in the economies in transition) and of related emissions. It assesses the technical and cost-effective potential for a 40% and more decrease in urban energy intensities and SO 2 /NO x emissions by 2020, resulting from a systematic approach to urban as well as energy planning. Compared to approaches worldwide, urban energy renewal in the economies in transition appears, as its beginning, characterized by a traditional focus on existing technological supply sub-systems such as district heating and co-generation. The obstacles to a more systematic approach, including demand side management, are slow progress in urban and energy reforms and a lack of acquaintance with modern planning tools. International cooperation is incommensurate with the long-term challenge of s ustainable urban development . (author)

  20. Forbidden transitions in excitation by electron impact in Co3+: an R-matrix approach

    International Nuclear Information System (INIS)

    Stancalie, V

    2011-01-01

    Collision strengths for the electron-impact excitation of forbidden transitions between 136 terms arising from 3d 6 , 3d 5 4s and 3d 5 4p configurations of Co 3+ have been calculated using the R-matrix method. The accuracy of a series of models for the target terms was considered, which form the basis for R-matrix collision calculations. The importance of including configuration interaction wave functions both in the target-state expansion and in the (N+1)-electron quadratically integrable function expansion is discussed. Collision strengths were calculated for incident electron energies up to 6 Ryd. These results are believed to be the first such values for this system and will be important for plasma modelling.

  1. Imaging ultrafast excited state pathways in transition metal complexes by X-ray transient absorption and scattering using X-ray free electron laser source

    DEFF Research Database (Denmark)

    Chen, Lin X; Shelby, Megan L; Lestrange, Patrick J

    2016-01-01

    This report will describe our recent studies of transition metal complex structural dynamics on the fs and ps time scales using an X-ray free electron laser source, Linac Coherent Light Source (LCLS). Ultrafast XANES spectra at the Ni K-edge of nickel(ii) tetramesitylporphyrin (NiTMP) were measured...... on the low-energy shoulder of the edge, which is aided by the computation of X-ray transitions for postulated excited electronic states. The observed and computed inner shell to valence orbital transition energies demonstrate and quantify the influence of the electronic configuration on specific metal...

  2. High-Resolution Measurements of Low-Energy Conversion Electrons

    CERN Multimedia

    Gizon, A; Putaux, J

    2002-01-01

    Measurements of low-energy internal conversion electrons have been performed with high energy resolution in some N = 105 odd and odd-odd nuclei using a semi-circular spectrograph associated to a specific tape transport system. These experiments aimed to answer the following questions~: \\begin{itemize} \\item Do M3 isomeric transitions exist in $^{183}$Pt and $^{181}$Os, isotones of $^{184}$Au~? \\item Are the neutron configurations proposed to describe the isomeric and ground states of $^{184}$Au right or wrong~? \\item Does it exist an isomeric state in $^{182}$Ir, isotone of $^{181}$Os, $^{183}$Pt and $^{184}$Au~? \\item What are the spin and parity values of the excited states of $^{182}$Ir~? \\end{itemize} In $^{183}$Pt, the 35.0 keV M3 isomeric transition has been clearly observed and the reduced transition probability has been determined. The deduced hindrance factor is close to that observed in the neighbouring odd-odd $^{184}$Au nucleus. This confirms the neutron configurations previously proposed for the ...

  3. On selection rules and inelastic electron scattering at intermediate energies

    International Nuclear Information System (INIS)

    Nuroh, K.

    1986-12-01

    Correlation effects are included in the Bethe-Born theory for the generalized oscillator strength of inelastic scattering of electrons on atoms. The formulation is such as to allow for the calculation of relative line strengths of multiplets. It is used to analyze line strengths of the 4d → 4f transition in La 3+ and Ce 4+ within LS-coupling. The analysis indicates that only singlet states of the intermediate 4d 9 4f configuration are allowed. Calculated line strengths are compared with a recent core electron energy loss spectra of metallic La and tetravalent CeO 2 and there is an overall qualitative agreement between theory and experiment. (author). 11 refs, 4 figs, 2 tabs

  4. Potential of forestry biomass for energy in economies in transition

    International Nuclear Information System (INIS)

    Apalovic, R.

    1995-01-01

    A rapid increase in the world's population, the gradual exhaustion of fossil fuels and serious ecological problems are making developed countries more attentive to the utilization of renewable energy sources, mainly biomass, which should form part of the global energy mix during the twenty-first century. The economies in transition have been experiencing a transformation of their political, economic and social systems and a modernization of their industry, including the energy industry. Energy supply in the transition economies is based on coal, oil, gas and nuclear power. Of the renewable sources, only hydroelectric power is utilized to any significant extent. The forest biomass resources of these economies are quantified in this paper. The economies in transition have a big potential for biomass from forestry and timber industry wastes and agricultural wastes that are not being utilized and could become a source of energy. So far, biomass is used as a source of energy in only small amounts in the wood and pulp industries and as fuelwood in forestry. The governments of some countries (the Czech Republic, Hungary and Slovakia) have energy plans through the year 2010 that aim to develop renewable energy sources. Economic, institutional, technical and other barriers to the development of renewable sources and their utilization are analysed in this paper and some remedies are proposed. In cooperation with countries such as Austria, Denmark, Sweden, Finland, the United States of America and others, which have achieved remarkable results in the utilization of biomass for energy, it would be possible for the transition economies to quickly develop the technological know-how needed to satisfy the demand for energy of approximately 350 million inhabitants. (author)

  5. Potential of forestry biomass for energy in economies in transition

    Energy Technology Data Exchange (ETDEWEB)

    Apalovic, R [State Forest Products Research Institute and Slovak Biomass Association, Bratislava (Slovakia)

    1995-12-01

    A rapid increase in the world`s population, the gradual exhaustion of fossil fuels and serious ecological problems are making developed countries more attentive to the utilization of renewable energy sources, mainly biomass, which should form part of the global energy mix during the twenty-first century. The economies in transition have been experiencing a transformation of their political, economic and social systems and a modernization of their industry, including the energy industry. Energy supply in the transition economies is based on coal, oil, gas and nuclear power. Of the renewable sources, only hydroelectric power is utilized to any significant extent. The forest biomass resources of these economies are quantified in this paper. The economies in transition have a big potential for biomass from forestry and timber industry wastes and agricultural wastes that are not being utilized and could become a source of energy. So far, biomass is used as a source of energy in only small amounts in the wood and pulp industries and as fuelwood in forestry. The governments of some countries (the Czech Republic, Hungary and Slovakia) have energy plans through the year 2010 that aim to develop renewable energy sources. Economic, institutional, technical and other barriers to the development of renewable sources and their utilization are analysed in this paper and some remedies are proposed. In cooperation with countries such as Austria, Denmark, Sweden, Finland, the United States of America and others, which have achieved remarkable results in the utilization of biomass for energy, it would be possible for the transition economies to quickly develop the technological know-how needed to satisfy the demand for energy of approximately 350 million inhabitants. (author) 6 refs, 4 figs, 4 tabs

  6. Pluri-annual energy programming - The Energy transition for green growth. Synthesis

    International Nuclear Information System (INIS)

    2016-01-01

    The Energy Transition for Green Growth Act and its attendant action plans are designed to give France the means to make a more effective contribution to tackling climate change and reinforce its energy independence, while striking a better balance in its energy mix and creating jobs and business growth. This document summarizes the content of the Pluri-annual energy programming, which is the consistent action framework of the French energy transition: improving energy efficiency and reducing fossil fuels consumption, accelerating the development of renewable energy sources, maintaining a high-level of security of supply in the respect of environmental requirements, preparing tomorrow's energy system, developing clean mobility, taking account of the socio-economic issues of the energy transition and acting with the regions in this way

  7. Energy Transition in the Nebular City: Connecting Transition Thinking, Metabolism Studies, and Urban Design

    Directory of Open Access Journals (Sweden)

    Griet Juwet

    2018-03-01

    Full Text Available Transforming urban infrastructures is an essential part of creating more sustainable urban regions. But rethinking these complex systems requires a better understanding of their spatial dimensions and their relation with urban morphology and spatial structure. This paper addresses that gap by examining different conceptualizations of technical infrastructure and space in science, technology and society studies (STS, transition thinking, urban metabolism studies, and urban political ecology, and draws connections with the spatial perspective of urban planning and design. It illustrates and tests these concepts through the case of energy transition in the Flemish region of Belgium. Transport and supply networks have played a crucial role in facilitating, structuring, and reproducing the region’s characteristic dispersed and energy-intensive urban landscape. Bringing different disciplinary perspectives together, the research broadens the conceptualization of the spatial dimension in transition thinking, and identifies useful concepts and design parameters for urban design to engage with the technical and socio-political complexity of transforming urban infrastructure. It reveals the energy transition as an inherently spatial project, and explores the spatially and socio-politically transformative potential of the transition towards a new energy system.

  8. Ideal glass transitions in thin films: An energy landscape perspective

    Science.gov (United States)

    Truskett, Thomas M.; Ganesan, Venkat

    2003-07-01

    We introduce a mean-field model for the potential energy landscape of a thin fluid film confined between parallel substrates. The model predicts how the number of accessible basins on the energy landscape and, consequently, the film's ideal glass transition temperature depend on bulk pressure, film thickness, and the strength of the fluid-fluid and fluid-substrate interactions. The predictions are in qualitative agreement with the experimental trends for the kinetic glass transition temperature of thin films, suggesting the utility of landscape-based approaches for studying the behavior of confined fluids.

  9. Energy transition of a sector in the Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Opstelten, I.J. [Energy research Centre of the Netherlands ECN, Petten (Netherlands); Weterings, R. [TNO, Delft (Netherlands); Versteeg, F.A. [FORGOOD, Amsterdam (Netherlands)

    2010-09-15

    To realize the energy transition in the building sector, three types of obstacles have to be overcome: technology-related, process-related and integration of technology and process. To this end an innovation / implementation program has been set up. The intrinsic driver of the program is the realization of increasingly more ambitious energy concepts in three successive waves, allowing for the different actors to learn from the previous wave, to prepare for the next wave and to scale up these type of projects both in terms of quantity and quality. The establishment process of the program identified a key success factor for the transition process itself: the role of the individual.

  10. Energy Transition of a Sector in The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Opstelten, I.J. [Energy in the Built Environment, Energy research Centre of the Netherlands ECN, Petten (Netherlands); Weterings, R. [TNO Innovation and Environment, Delft (Netherlands); Versteeg, F.A. [FORGOOD, Hilversum (Netherlands)

    2010-09-15

    To realize the energy transition in the building sector, three types of obstacles have to be overcome: technology-related, process-related and integration of technology and process. To this end an innovation-implementation program has been constructed. The intrinsic driver of the program is the realization of increasingly more ambitious energy concepts in three successive waves, allowing for the different actors to learn from the previous wave, to prepare for the next wave and to scale up these type of projects both in terms of quantity and quality. The establishment process of the program identified a key success factor for the transition process itself: the role of the individual.

  11. Review of urban energy transition in the Netherlands and the role of smart energy management

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; de Wit, J.B.; Smit, Gerardus Johannes Maria

    2017-01-01

    This paper gives a review of the most important backgrounds and trends of the present energy supply system in the Netherlands. Options are discussed for the integration of renewable energy and the present policies are reviewed that stimulate the energy transition. Last, the role of smart energy

  12. Transition to distributed energy generation in Finland: Prospects and barriers

    International Nuclear Information System (INIS)

    Ruggiero, Salvatore; Varho, Vilja; Rikkonen, Pasi

    2015-01-01

    Small-scale distributed energy generation is expected to play an important role in helping Finland increase its energy self-sufficiency. However, the overall strategy to date for promoting distributed energy remains unclear. It is not yet well understood which factors promote the growth of the distributed energy sector and what barriers need to be removed. In this article we present the results of a questionnaire directed at a panel of 26 experts from the distributed energy value chain and 15 semi-structured interviews with industry and non-industry representatives. We investigated, from a sociotechnical transition perspective, the possibilities and challenges of the transition to distributed energy in Finland through 2025. The results show that a shift to a prosperous future for distributed energy is possible if permit procedures, ease of grid connection, and taxation laws are improved in the electricity sector and new business concepts are introduced in the heat sector. In contrast to other European countries, the transition in Finland is expected to take place through a market-based approach favoring investment-focused measures. We conclude that incentive-based schemes alone, whatever they may be, will be insufficient to create significant growth in Finland without institutional change, removal of barriers, and the engagement of key actors. - Highlights: • We examine the possibilities and challenges of the transition to DE in Finland. • Technological niches are emerging both in the heat and electricity sector. • Business model innovation is evident only in the electricity sector. • Removing barriers and developing new business models will accelerate the transition.

  13. Electric grids and energy transition in Europe

    International Nuclear Information System (INIS)

    Cruciani, Michel

    2015-06-01

    Focussing on electricity, this report proposes an analysis of the main elements in favour of large investments in electric grids, while notably outlining technical or economic uncertainties as well as possible political consequences such as compatibility of a largely interconnected European network with a free choice of energy sources (as specified in the Lisbon Treaty), and responsibility for the States in terms of supply security. The author first describes the present situation: overview of the regulatory framework of the liberalization process. The second part addresses challenges which emerged with the European commitment in favour of renewable sources of electricity and the emergence of new needs, notably regarding electric vehicles. It also presents measures aimed at supporting the development of networks. The third part introduces a discussion about the relevancy of this development by highlighting, on the one hand, the fragility of economic perspectives, and on the other hand, the necessity to address future consequences of a major increase of interconnections within the European electric grid. Some recommendations are finally proposed. Examples and specific analysis more particularly concern Germany, Spain, France, Italy and the United-Kingdom

  14. Review of urban energy transition in the Netherlands and the role of smart energy management

    International Nuclear Information System (INIS)

    Leeuwen, R.P. van; Wit, J.B. de; Smit, G.J.M.

    2017-01-01

    Highlights: • Review of backgrounds and trends of the energy supply system in the Netherlands. • Review of Dutch governance policies to support the energy transition. • Review of increasing energy efficiency and options for supply and storage of renewable energy. • Individual and collective approaches to integrate renewable energy in the built environment. • The role of smart energy management to integrate renewable energy into existing infrastructures. - Abstract: This paper gives a review of the most important backgrounds and trends of the present energy supply system in the Netherlands. Options are discussed for the integration of renewable energy and the present policies are reviewed that stimulate the energy transition. Last, the role of smart energy management as part of the integration of renewable energy into existing infrastructures is discussed.

  15. 15 signals evidence the energy transition is underway

    International Nuclear Information System (INIS)

    2016-09-01

    World leaders approved a universal climate agreement in Paris last year, drawing a line in the sand for the transformation of the world's energy system into a clean and sustainable form. Signs that a global energy transition is happening are everywhere to be seen: in the growth of renewables, the rise of city-level climate actions, the stagnation of CO 2 emissions and in companies who are committing to science based targets as the foundation of their climate actions, to name just a few. We felt it important to highlight 15 key signs or 'signals' of the energy transition, to help raise awareness that the transition to a new, sustainable, equitable, just and fair global energy system has irrevocably begun. What is needed now is to accelerate the transition and scale it up to have a chance of keeping global temperature rise to well below 2 deg. C, trying for 1.5 deg. C, as countries committed to in the Paris Agreement just eight months ago. Global meetings such as the G20 meeting taking place in China on 4-5 September; and the next UN climate talks starting in Marrakech on 7 November gives opportunity to all stakeholders to say how and what they can contribute to accelerating the transition. Ending fossil fuel subsidies, supporting the deployment of renewables and energy efficiency, increasing green finance and putting a just price on carbon are just some of the actions that can be taken right now to put pace into the transition. As 2016 heads into the record books as likely the hottest year ever recorded in history, it is a reminder that we have precious little time left to act to keep global temperatures well below 2 deg. C. We have the Paris Agreement to guide our way. Now we need to implement it. Now is the time for action

  16. Regional debate on energy transition - 17 May 2013

    International Nuclear Information System (INIS)

    Gay, Michel

    2013-01-01

    In this conference, the author discusses the objectives of energy transition in France, and the objectives of the debate on this issue, and addresses three important questions raised by this issue: how to move towards energy efficiency and energy sobriety, which pathway to reach the targeted energy mix in 2025, which are the costs, benefits and financing of energy transition. He describes the complexity of the problem and its contradictory aspects (how to produce more energy with less oil, gas and coal). As far as the first question is concerned (energy efficiency and sobriety), he discusses the notion of energy sobriety, what is at stake (supply security, economic, social and climatic challenges), the strategic objectives, the evolution of energy consumption and production, the leading role of electricity, the CO 2 emissions by different economic sectors, the level of energy imports, the issue of electricity price. As far as the two other questions are concerned, he discusses the opportunities associated with the building and transport sectors, the issue of energy storage, and the role of EDF. In a second part, the author criticizes the Negawatt scenario, and the ADEME's position and action, and discusses opportunities related to energy efficiency, the decrease of the use of fossil energy, the promotion of electricity, and the preservation of nuclear energy as a French asset. He comments the statements of French political actors, the evolution of wind energy production in Europe, the low level of energy and electricity production by the French wind turbines. He discusses a comparison between coal and nuclear in terms of production and pollution, the issue of nuclear waste management, the perspectives for nuclear reactors, the situation in other countries (Switzerland, Germany). He notably outlines that phasing out nuclear in Germany results in the use of coal plants and gas imports

  17. Trends in elasticity and electronic structure of 5d transition metal diborides: first-principles calculations

    International Nuclear Information System (INIS)

    Hao Xianfeng; Wu Zhijian; Xu Yuanhui; Zhou Defeng; Liu Xiaojuan; Meng Jian

    2007-01-01

    We investigate the cohesive energy, heat of formation, elastic constant and electronic band structure of transition metal diborides TMB 2 (TM = Hf, Ta, W, Re, Os and Ir, Pt) in the Pmmn space group using the ab initio pseudopotential total energy method. Our calculations indicate that there is a relationship between elastic constant and valence electron concentration (VEC): the bulk modulus and shear modulus achieve their maximum when the VEC is in the range of 6.8-7.2. In addition, trends in the elastic constant are well explained in terms of electronic band structure analysis, e.g., occupation of valence electrons in states near the Fermi level, which determines the cohesive energy and elastic properties. The maximum in bulk modulus and shear modulus is attributed to the nearly complete filling of TM d-B p bonding states without filling the antibonding states. On the basis of the observed relationship, we predict that alloying W and Re in the orthorhombic structure OsB 2 might be harder than alloying the Ir element. Indeed, the further calculations confirmed this expectation

  18. Trends in elasticity and electronic structure of 5d transition metal diborides: first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Hao Xianfeng [Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Wu Zhijian [Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Xu Yuanhui [School of Biological Engineering, Changchun University of Technology, Changchun 130012 (China); Zhou Defeng [School of Biological Engineering, Changchun University of Technology, Changchun 130012 (China); Liu Xiaojuan [Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Meng Jian [Key Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2007-05-16

    We investigate the cohesive energy, heat of formation, elastic constant and electronic band structure of transition metal diborides TMB{sub 2} (TM = Hf, Ta, W, Re, Os and Ir, Pt) in the Pmmn space group using the ab initio pseudopotential total energy method. Our calculations indicate that there is a relationship between elastic constant and valence electron concentration (VEC): the bulk modulus and shear modulus achieve their maximum when the VEC is in the range of 6.8-7.2. In addition, trends in the elastic constant are well explained in terms of electronic band structure analysis, e.g., occupation of valence electrons in states near the Fermi level, which determines the cohesive energy and elastic properties. The maximum in bulk modulus and shear modulus is attributed to the nearly complete filling of TM d-B p bonding states without filling the antibonding states. On the basis of the observed relationship, we predict that alloying W and Re in the orthorhombic structure OsB{sub 2} might be harder than alloying the Ir element. Indeed, the further calculations confirmed this expectation.

  19. Energy Transition Initiative, Island Energy Snapshot - Grenada (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-03-01

    This profile provides a snapshot of the energy landscape of Grenada - a small island nation consisting of the island of Grenada and six smaller islands in the southeastern Caribbean Sea - three of which are inhabited: Grenada, Carriacou, and Petite Martinique.

  20. Accelerating Energy and Environmental Transition in Europe through digital

    International Nuclear Information System (INIS)

    Reinaud, Julia; Clinckx, Nicolas; Faraggi, Paul

    2017-01-01

    Digitalization is becoming ubiquitous in the energy sector, enabling a more decentralized energy system and blurring the traditional energy sector boundaries, with more integration with buildings, mobility solutions and industry. Digitalization is accelerating the pace of the energy transition, mainly thanks to three levers: 1) enhancing customer interaction with the energy system, 2) optimizing operations, and 3) enabling new business models for traditional energy actors as well as opening up space for new entrants from other sectors and energy start-ups. Digital technologies are also facilitating a cost-effective, clean energy transition, mainly by increasing energy efficiency and flexibility, as well as enabling the integration of renewable electricity into smart(er) grids and developing low-carbon solutions. This article gives a brief overview of the digitally-enabled innovations in Europe's energy markets and how various players are positioning themselves to take advantage of these opportunities. It concludes by highlighting some of the policy issues this transformation raises and the challenges ahead for European businesses to reap the benefits

  1. Energy Transition and Barriers on the Path to its Introduction

    Directory of Open Access Journals (Sweden)

    Tomislav Tkalec

    2015-12-01

    Full Text Available Energy transition is a concept originating from the necessity of solving environmental problems and conflicts in the energy sector. It originates from environmental tradition and advocates transition from environmentally and socially controversial sources of energy to renewables. That also means a shift from large centralized production units (mainly based on fossil and nuclear energy to smaller, dispersed ones. This decentralization process inherently leads to a democratization of the electricity sector, as large energy companies are losing their power and position in the energy policy arena, as more and more smaller actors emerge. However, when trying to change the electricity system, many obstacles arise – from the economics, old energy paradigm, path dependence, inertia of electricity system, power relations between actors, institutional lock-in, to perceptions and values of the dominant players. All barriers are reflected in the energy policy arena, dominated mainly by large energy companies, reluctant to accept changes. Demands for a change come from non-dominant actors, mainly from civil society actors and others, who are pushed to the margins of the political arena. Therefore, decision-makers should recognize their role, change institutional structure of the energy policy arena, and open it to various actors that can add new qualities to decision-making processes and outputs.

  2. Beam diagnostics using transition radiation produced by a 100 Mev electron beam

    International Nuclear Information System (INIS)

    Jablonka, M.; Leroy, J.; Hanus, X.; Derost, J.C.; Wartski, L.

    1991-01-01

    We report on several experiments using the optical transition radiation (OTR) produced by a 100 MeV electron beam. In using a sensitive video camera coupled with a digital image processing system an accurate and simple beam profile monitor has been devised. In measuring with a photo-multiplier the radiation emitted in a small solid angle around the direction of the OTR emission, a signal very sensitive to beam energy variations has been obtained. These experiments have been carried out on the Saclay ALS linac

  3. Low energy electron transport in furfural

    International Nuclear Information System (INIS)

    Lozano, A.I.; Garcia, G.; Krupa, K.; Ferreira da Silva, F.; Limao-Vieira, P.; Blanco, F.; Munoz, A.; Jones, D.B.; Brunger, M.J.

    2017-01-01

    The cyclic configuration of the furfural molecule is similar to the 5-membered ring structure constituting the sugar units of the DNA helix, hence its importance in biology. In this paper, we report on an initial investigation into the transport of electrons through a gas cell containing 1 mtorr of gaseous furfural. Results from our Monte Carlo simulation are implicitly checked against those from a corresponding electron transmission measurement. To enable this simulation a self-consistent cross section data base was constructed. This data base is benchmarked through new total cross section measurements which are also described here. In addition, again to facilitate the simulation, our preferred energy loss distribution function is presented and discussed

  4. Exploring the transition potential of renewable energy communities

    NARCIS (Netherlands)

    Doci, G.; Vasileiadou, E.; Petersen, A.H.

    2014-01-01

    Although in the last decades a transition toward a sustainable energy system with renewables has been advocated by many, it is still uncertain where the support and required investments for renewables can come from. In this article we introduce and analyze a special type of investor group: renewable

  5. Hydraulic fracturing, energy transition and political engagement in the Netherlands

    NARCIS (Netherlands)

    Rasch, Elisabet Dueholm; Köhne, Michiel

    2016-01-01

    This paper analyses how citizens (re)define their relation to the state in the contestation of hydraulic fracturing in the Noordoostpolder (the Netherlands) in the context of energy transition. It approaches citizenship as the negotiations between governments and citizens about in-and exclusion

  6. What energy transition for France? Priority to employment and environment

    International Nuclear Information System (INIS)

    2013-01-01

    France is one of the countries with the lowest greenhouse gas emissions per inhabitant ratio. Even if this environmental effort must be maintained, it has to be done in the respect of competitiveness and employment. In this paper, the authors reviewed some received ideas and shed light on the objectives to be pursued in the framework of the announced energy transition

  7. Participating to the Transition Towards New Energy Technology Systems

    International Nuclear Information System (INIS)

    Tosato, G.

    2008-01-01

    The paper analyses possible implications for Croatia of a global transition towards new energy technology systems, as depicted by the recent report on scenarios and strategies to 2050 of the International Energy Agency [ETP2008]. The analysis is based upon the present Croatian energy balance. It takes into account some draft results of the USAID-supported Regional Energy Demand Planning (REDP) study under the South East Europe Regional Energy Market Support (SEE REMS) Project. The paper then presents ongoing EC-funded energy research projects, such as RES2020 (Monitoring and Evaluation of the Renewable Energy Sources directives implementation in EU27 and policy recommendations for 2020), REACCESS (Risk of Energy Availability: Common Corridors for Europe Supply Security) and REALISEGRID (REseArch, methodoLogIes and technologieS for the effective development of pan-European key GRID infrastructures to support the achievement of a reliable, competitive and sustainable electricity supply). The participation of Croatian research organizations to EC-funded research projects could make the transition towards new energy system an opportunity for economic development.(author)

  8. Combined effect of dopant and electron beam-irradiation on phase transition in lithium potassium sulphate

    Science.gov (United States)

    Kassem, M. E.; Gaafar, M.; Abdel Gawad, M. M. H.; El-Muraikhi, M.; Ragab, I. M.

    2004-02-01

    Thermodynamic studies of polycrystalline ruthenium (Ru) doped LiKSO 4 have been made for different concentrations of Ru in the range 0%, 0.1%, 0.2%, 0.5%, 1%, 2%, 3% by weight. The thermal behaviour has been investigated using a differential scanning calorimeter in the vicinity of high temperature phases. From this, the effect of electron beam-irradiation on the thermal properties of these polycrystalline samples has been studied. The results showed a change in the transition temperature Tc, as well as the value of specific heat CPmax at the transition temperature due to the change in Ru content and irradiation energies. The change of enthalpy and entropy of the polycrystalline have been estimated numerically.

  9. Combined effect of dopant and electron beam-irradiation on phase transition in lithium potassium sulphate

    International Nuclear Information System (INIS)

    Kassem, M.E.; Gaafar, M.; Abdel Gawad, M.M.H.; El-Muraikhi, M.; Ragab, I.M.

    2004-01-01

    Thermodynamic studies of polycrystalline ruthenium (Ru) doped LiKSO 4 have been made for different concentrations of Ru in the range 0%, 0.1%, 0.2%, 0.5%, 1%, 2%, 3% by weight. The thermal behaviour has been investigated using a differential scanning calorimeter in the vicinity of high temperature phases. From this, the effect of electron beam-irradiation on the thermal properties of these polycrystalline samples has been studied. The results showed a change in the transition temperature T c , as well as the value of specific heat C P max at the transition temperature due to the change in Ru content and irradiation energies. The change of enthalpy and entropy of the polycrystalline have been estimated numerically

  10. Renewable Energy Policies in a Time of Transition

    International Nuclear Information System (INIS)

    Murdock, Hannah E.; Adib, Rana; Lins, Christine; Guerra, Flavia; Misra, Archita; Murdock, Hannah E.; Vickery, Louise; Collier, Ute; Le Feuvre, Pharoah; Bianco, Emanuele; Mueller, Simon; Philibert, Cedric; Schmidt, Oliver; Kvarnstroem, Oskar; Collier, Ute; Hungerford, Zoe; Frankl, Paolo; Bianco, Emanuele; Hawila, Diala; Ferroukhi, Rabia; Hawila, Diala; Renner, Michael; Nagpal, Divyam; Cox, Sadie; Esterly, Sean; Priesmann, Caspar; Taylor, Hadley; Breitschopf, Barbara; Van Rooijen, Sascha

    2018-01-01

    Spurred by innovation, increased competition, and policy support in a growing number of countries, renewable energy technologies have achieved massive technological advances and sharp cost reductions. Renewables have come to the forefront of the global energy transition, with nearly every country adopting a renewable energy target. Yet progress has been uneven in different countries and sectors. Technology and financial risks still hamper the expansion of renewables into new markets. As the power sector develops further, the increased adoption of variable renewables like solar and wind requires more flexible systems. Compared to power generation, the regulatory framework for end-use sectors lags behind. This report, prepared jointly by the International Renewable Energy Agency (IRENA), the International Energy Agency (IEA) and the Renewable Energy Policy Network for the 21. Century (REN21), identifies key barriers and highlights policy options to boost renewable energy deployment. After reviewing current policies and targets worldwide, it examines sector-specific policies for heating and cooling, transport and power, as well as measures for integrating variable renewables. An updated policy classification and terminology list can serve as a global reference for renewable energy policy instruments. Among the key findings: Renewable energy policies must focus on end-use sectors, not just power generation; The use of renewables for heating and cooling requires greater policy attention, including dedicated targets, technology mandates, financial incentives, generation-based incentives, and carbon or energy taxes; Policies in the transport sector require further development, including integrated policies to de-carbonise energy carriers and fuels, vehicles and infrastructure; Policies in the power sector must also evolve further to address new challenges. Measures are needed to support the integration of variable renewable energy, taking into account the specific

  11. Electronic specific heat of transition metal carbides; Chaleur specifique electronique de carbures de metaux de transition

    Energy Technology Data Exchange (ETDEWEB)

    Conte, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-15

    The experimental results that make it possible to define the band structure of transition metal carbides having an NaCI structure are still very few. We have measured the electronic specific heat of some of these carbides of varying electronic concentration (TiC, either stoichiometric or non-stoichiometric, TaC and mixed (Ti, Ta) - C). We give the main characteristics (metallography, resistivity, X-rays) of our samples and we describe the low temperature specific heat apparatus which has been built. In one of these we use helium as the exchange gas. The other is set up with a mechanical contact. The two use a germanium probe for thermometer. The measurement of the temperature using this probe is described, as well as the various measurement devices. The results are presented in the form of a rigid band model and show that the density of the states at the Fermi level has a minimum in the neighbourhood of the group IV carbides. (author) [French] Les donnees experimentales permettant de preciser la structure de bandes des carbures de metaux de transition de structure NaCI sont encore peu.nombreuses. Nous avons mesure la chaleur specifique electronique de certains de ces carbures, de differentes concentrations electroniques (TiC stoechiometrique ou non, TaC et mixtes (Ti, Ta) - C). Nous donnons les principales caracteristiques (metallographie, resistivite, rayon X), de nos echantillons, et nous decrivons l'appareillage de chaleur specifique a basse temperature realise. Dans l'un nous utilisons l'helium comme gaz d'echange. L'autre est monte avec un contact mecanique. Les deux utilisent une sonde au germanium comme thermometre. La mesure de la resistance de cette sonde est decrite, ainsi que les differents montages de mesure. Les resultats, presentes dans un modele de bande rigide, font apparaitre que la densite des etats au niveau de Fermi presente un minimum au voisinage des carbures du groupe IV. (auteur)

  12. QED corrections to the 4p-4d transition energies of copperlike heavy ions

    International Nuclear Information System (INIS)

    Chen, M. H.; Cheng, K. T.; Johnson, W. R.; Sapirstein, J.

    2006-01-01

    Quantum electrodynamic (QED) corrections to 4p-4d transition energies of several copperlike ions with Z=70-92 are calculated nonperturbatively in strong external fields to all orders in binding corrections. Dirac-Kohn-Sham potentials are used to account for screening and core-relaxation effects. For the 4p 1/2 -4d 3/2 transition in copperlike bismuth, thorium, and uranium, results are in good agreement with empirical QED corrections deduced from differences between transition energies obtained from recent high-precision electron-beam ion-trap measurements and those calculated with the relativistic many-body perturbation theory (RMBPT). These comparisons provide sensitive tests of QED corrections for high-angular-momentum states in many-electron heavy ions and illustrate the importance of core-relaxation corrections. Comparisons are also made with other theories and with experiments on the 4s-4p transition energies of high-Z Cu-like ions as accuracy checks of the present RMBPT and QED calculations

  13. Electron beam accelerator energy control system

    International Nuclear Information System (INIS)

    Sharma, Vijay; Rajan, Rehim; Acharya, S.; Mittal, K.C.

    2011-01-01

    A control system has been developed for the energy control of the electron beam accelerator using PLC. The accelerating voltage of 3 MV has been obtained by using parallel coupled voltage multiplier circuit. A autotransformer controlled variable 0-10 KV DC is fed to a tube based push pull oscillator to generate 120 Khz, 10 KV AC. Oscillator output voltage is stepped up to 0-300 KV/AC using a transformer. 0-300 KVAC is fed to the voltage multiplier column to generate the accelerating voltage at the dome 0-3 MV/DC. The control system has been designed to maintain the accelerator voltage same throughout the operation by adjusting the input voltage in close loop. Whenever there is any change in the output voltage either because of beam loading or arcing in the accelerator. The instantaneous accelerator voltage or energy is a direct proportional to 0-10 KVDC obtained from autotransformer. A PLC based control system with user settable energy level has been installed for 3 MeV, EB accelerator. The PLC takes the user defined energy value through a touch screen and compares it to the actual accelerating voltage (obtained using resistive divider). Depending upon the error the PLC generates the pulses to adjust the autotransformer to bring the actual voltage to the set value within the window of error (presently set to +/- 0.1%). (author)

  14. (Electronic structure and reactivities of transition metal clusters)

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The following are reported: theoretical calculations (configuration interaction, relativistic effective core potentials, polyatomics, CASSCF); proposed theoretical studies (clusters of Cu, Ag, Au, Ni, Pt, Pd, Rh, Ir, Os, Ru; transition metal cluster ions; transition metal carbide clusters; bimetallic mixed transition metal clusters); reactivity studies on transition metal clusters (reactivity with H{sub 2}, C{sub 2}H{sub 4}, hydrocarbons; NO and CO chemisorption on surfaces). Computer facilities and codes to be used, are described. 192 refs, 13 figs.

  15. 3rd International Workshop on Desorption Induced by Electronic Transitions

    CERN Document Server

    Knotek, Michael

    1988-01-01

    These proceedings are the result of the third international workshop on Desorption Induced by Electronic Transitions, DIET III, which took place on Shelter Island, NY, May. 20-22, 1987. The work contained in this volume is an excellent summary of the current status of the field and should be a valuable reference text for both "seasoned" researchers and newcomers in the field of DIET. Based on the success of the meeting it seems clear that interest and enthusiasm in the field is strong. It is also apparent, from the many lively discussions during the meeting, that many unanswered questions (and controversies) remain to be solved. It was particularly pleasing to see many new participants from new and rapidly advancing fields, ranging from gas phase dynamics to semiconductor processing. The resulting cross-fertilization from these separate but related fields is playing an important role in helping us understand desorption processes at solid surfaces. In general, the topics covered during the course of the worksh...

  16. 2nd International Workshop on Desorption Induced by Electronic Transitions

    CERN Document Server

    Menzel, Dietrich

    1985-01-01

    The second workshop on Desorption Induced by Electronic Transitions (DIET II) took place October 15-17, 1984, in SchloB Elmau, Bavaria. DIET II, fol­ lowing the great success of DIET I (edited by N. H. Tolk, M. M. Traum, J. C. Tully, T. E. Madey and published in Springer Ser. Chem. Phys. , Vol. 24), again brought together over 60 workers in this exciting field. The "hard co­ re of experts" was essentially the same as in DIET I but the general overlap of participants between the two meetings was small. While DIET I had the function of an exposition of the status of the field DIET II focussed more on new developments. The main emphasis was again on the microscopic under­ standing of DIET but a number of side aspects and the application of DIET ideas to other fields such as sputtering, laser-induced desorption, fractu­ re, erosion, etc. were considered, too. New mechanisms and new refined expe­ rimental techniques were proposed and discussed at the meeting critically but with great enthusiasm. In addition t...

  17. What drives energy consumers? : Engaging people in a sustainable energy transition

    NARCIS (Netherlands)

    Steg, Linda; Shwom, Rachel; Dietz, Thomas

    Providing clean, safe, reliable, and affordable energy for people everywhere will require converting to an energy system in which the use of fossil fuels is minimal. A sustainable energy transition means substantial changes in technology and the engagement of the engineering community. But it will

  18. Low-energy electron scattering from pyrimidine: Similarities and differences with benzene

    Science.gov (United States)

    Jones, D. B.; Bellm, S. M.; Limão-Vieira, P.; Brunger, M. J.

    2012-05-01

    Differential cross sections for low-energy electron-impact excitation of the unresolved combinations of 23B2 + 21A1 and 31A1 + 21B2 electronic states of pyrimidine are reported. Comparisons are made with recent differential cross section measurements for the electron-impact excitation of the 1E1u and unresolved 1B1u + 3E2g electronic states of benzene [H. Kato, M. Hoshino, H. Tanaka, P. Limão-Vieira, O. Ingolfsson, L. Campbell, M.J. Brunger, J. Chem. Phys. 134 (2011) 134308.], in order to evaluate the nature of electron impact π-π∗ transitions in aromatic species.

  19. A phase transition in energy-filtered RNA secondary structures

    DEFF Research Database (Denmark)

    Han, Hillary Siwei; reidys, Christian

    2012-01-01

    In this paper we study the effect of energy parameters on minimum free energy (mfe) RNA secondary structures. Employing a simplified combinatorial energy model, that is only dependent on the diagram representation and that is not sequence specific, we prove the following dichotomy result. Mfe...... this phase transition from a discrete limit to a central limit distribution and subsequently put our result into the context of quantifying the effect of sparsification of the folding of these respective mfe-structures. We show that the sparsification of realistic mfe-structures leads to a constant time...

  20. World in transition 3 towards sustainable energy systems

    CERN Document Server

    2014-01-01

    'The publication of World in Transition: Towards Sustainable Energy Systems is timely indeed. The World Summit on Sustainable Development gave great prominence to this challenge, but failed to agree on a quantitative, time-bound target for the introduction of renewable energy sources. The German Advisory Council on Global Change (WBGU) has now produced a report with a global focus, which is essential in view of the global impacts of climate change. The report provides a convincing long-term analysis, which is also essential. Global energy policies have to take a long-term perspective, over the

  1. Correlated structural and electronic phase transformations in transition metal chalcogenide under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chunyu, E-mail: licy@hpstar.ac.cn, E-mail: yanhao@hpstar.ac.cn; Ke, Feng; Yu, Zhenhai; Chen, Zhiqiang; Yan, Hao, E-mail: licy@hpstar.ac.cn, E-mail: yanhao@hpstar.ac.cn [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); Hu, Qingyang [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015 (United States); Zhao, Jinggeng [Natural Science Research Center, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080 (China)

    2016-04-07

    Here, we report comprehensive studies on the high-pressure structural and electrical transport properties of the layered transition metal chalcogenide (Cr{sub 2}S{sub 3}) up to 36.3 GPa. A structural phase transition was observed in the rhombohedral Cr{sub 2}S{sub 3} near 16.5 GPa by the synchrotron angle dispersive X-ray diffraction measurement using a diamond anvil cell. Through in situ resistance measurement, the electric resistance value was detected to decrease by an order of three over the pressure range of 7–15 GPa coincided with the structural phase transition. Measurements on the temperature dependence of resistivity indicate that it is a semiconductor-to-metal transition in nature. The results were also confirmed by the electronic energy band calculations. Above results may shed a light on optimizing the performance of Cr{sub 2}S{sub 3} based applications under extreme conditions.

  2. Electronic structure and quantum spin fluctuations at the magnetic phase transition in MnSi

    Science.gov (United States)

    Povzner, A. A.; Volkov, A. G.; Nogovitsyna, T. A.

    2018-05-01

    The effect of spin fluctuations on the heat capacity and homogeneous magnetic susceptibility of the chiral magnetic MnSi in the vicinity of magnetic transition has been investigated by using the free energy functional of the coupled electron and spin subsystems and taking into account the Dzyaloshinsky-Moriya interaction. For helical ferromagnetic ordering, we found that zero-point fluctuations of the spin density are large and comparable with fluctuations of the non-uniform magnetization. The amplitude of zero-point spin fluctuations shows a sharp decrease in the region of the magnetic phase transition. It is shown that sharp decrease of the amplitude of the quantum spin fluctuations results in the lambda-like maxima of the heat capacity and the homogeneous magnetic susceptibility. Above the temperature of the lambda anomaly, the spin correlation radius becomes less than the period of the helical structure and chiral fluctuations of the local magnetization appear. It is shown that formation of a "shoulder" on the temperature dependence of the heat capacity is due to disappearance of the local magnetization. Our finding allows to explain the experimentally observed features of the magnetic phase transition of MnSi as a result of the crossover of quantum and thermodynamic phase transitions.

  3. Electron energy deposition in the middle atmosphere

    International Nuclear Information System (INIS)

    Vampola, A.L.; Gorney, D.J.

    1983-01-01

    Spectra of locally precipating 36- to 317-keV electrons obtained by instrumentation on the S3-2 satellite are used to calculate energy deposition profiles as a function of latitude, longitude, and altitude. In the 70- to 90-km altitude, mid-latitude ionization due to these precipitating energetic electrons can be comparable to that due to direct solar H Lyman α. At night, the electrons produce ionization more than an order of magnitude greater than that expected from scattered H Lyman α. Maximum precipitation rates in the region of the South Atlantic Anomaly are of the order of 10 -2 erg/cm 2 s with a spectrum of form j(E) = 1.34 x 10 5 E/sup -2.27/ (keV). Southern hemisphere precipitation dominates that in the north for 1.1< L<6 except for regions of low local surface field in the northern hemisphere. Above L = 6, local time effects dominate: i.e., longitudinal effects due to the asymmetric magnetic field which are strong features below L = 6 disappear and are replaced by high-latitude precipitation events which are local time features

  4. Mott transition: Low-energy excitations and superconductivity

    International Nuclear Information System (INIS)

    Ioffe, L.B.; Larkin, A.I.

    1988-09-01

    It is possible that metal-dielectric transition does not result in changes of magnetic or crystallographic symmetry. In this case a fermionic spectrum is not changed at the transition, but additional low-energy excitations appear which can be described as a gauge field that has the same symmetry as an electromagnetic one. In the case of a non half-filled band gapless scalar Bose excitations also appear. Due to the presence of additional gauge field the physical conductivity is determined by the lowest conductivity of the Fermi or Bose subsystems. (author). 11 refs

  5. Transitions and transition management. The case of an emission-low energy supply

    International Nuclear Information System (INIS)

    Rotmans, J.; Van Asselt, M.; Molendijk, K.; Kemp, R.; Geels, F.; Verbong, G.

    2000-12-01

    Transitions are societal transformation processes that occur in at least one generation (i.e. 25 years). Transitions are structural changes of the society or a complex part of that society. Transitions show technological, economical, ecological, socio-cultural and institutional developments on different levels. A transition is the result of slow changes (developments in supplies) and fast dynamics (flows). In general, four transition phases can be distinguished: (1) a pre-development phase of dynamic equilibrium in which the status quo does not change much; (2) a take-off phase in which the process of change is started; (3) an acceleration phase in which structural changes occur, resulting in collective learning processes, diffusion and processes of implementation; (4) a stabilization phase in which the speed of societal changes decreases and a new dynamic equilibrium exists. Within the framework of the preparatory process of the Fourth Dutch National Environmental Plan (NMP4) a study has been carried out to explore the transition concept, focusing on an emission-low energy supply in the Netherlands. 49 refs

  6. Quantum criticality around metal-insulator transitions of strongly correlated electron systems

    Science.gov (United States)

    Misawa, Takahiro; Imada, Masatoshi

    2007-03-01

    Quantum criticality of metal-insulator transitions in correlated electron systems is shown to belong to an unconventional universality class with violation of the Ginzburg-Landau-Wilson (GLW) scheme formulated for symmetry breaking transitions. This unconventionality arises from an emergent character of the quantum critical point, which appears at the marginal point between the Ising-type symmetry breaking at nonzero temperatures and the topological transition of the Fermi surface at zero temperature. We show that Hartree-Fock approximations of an extended Hubbard model on square lattices are capable of such metal-insulator transitions with unusual criticality under a preexisting symmetry breaking. The obtained universality is consistent with the scaling theory formulated for Mott transitions and with a number of numerical results beyond the mean-field level, implying that preexisting symmetry breaking is not necessarily required for the emergence of this unconventional universality. Examinations of fluctuation effects indicate that the obtained critical exponents remain essentially exact beyond the mean-field level. It further clarifies the whole structure of singularities by a unified treatment of the bandwidth-control and filling-control transitions. Detailed analyses of the criticality, containing diverging carrier density fluctuations around the marginal quantum critical point, are presented from microscopic calculations and reveal the nature as quantum critical “opalescence.” The mechanism of emerging marginal quantum critical point is ascribed to a positive feedback and interplay between the preexisting gap formation present even in metals and kinetic energy gain (loss) of the metallic carrier. Analyses of crossovers between GLW type at nonzero temperature and topological type at zero temperature show that the critical exponents observed in (V,Cr)2O3 and κ-ET -type organic conductors provide us with evidence for the existence of the present marginal

  7. Towards a fossil free energy future. The next energy transition

    Energy Technology Data Exchange (ETDEWEB)

    Lazarus, M.; Greber, L.; Hall, J.; Bartels, C.; Bernow, S.; Hansen, E.; Raskin, P.; Von Hippel, D. (Stockholm Environment Institute, Boston, MA (United States))

    1993-04-01

    The report provides technical analysis and documentation as input to the Greenpeace project 'Towards a fossil free energy future'. It presents a main scenario and several variants for reducing greenhouse gas emissions, and the technical methods and assumptions used to develop them. The goal is to investigate the technical, economic and policy feasibility to phasing out fossil fuels over the next century as part of a strategy to avert unacceptably high levels or rates of global warming. 209 refs., 42 figs., 27 tabs.

  8. Electronic transport and dielectric properties of low-dimensional structures of layered transition metal dichalcogenides

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Ashok, E-mail: ashok.1777@yahoo.com; Ahluwalia, P.K., E-mail: pk_ahluwalia7@yahoo.com

    2014-02-25

    Graphical abstract: We present electronic transport and dielectric response of layered transition metal dichalcogenides nanowires and nanoribbons. Illustration 1: Conductance (G) and corresponding local density of states(LDOS) for LTMDs wires at applied bias. I–V characterstics are shown in lowermost panels. Highlights: • The studied configurations show metallic/semiconducting nature. • States around the Fermi energy are mainly contributed by the d orbitals of metal atoms. • The studied configurations show non-linear current–voltage (I–V) characteristics. • Additional plasmonic features at low energy have been observed for both wires and ribbons. • Dielectric functions for both wires and ribbons are anisotropic (isotropic) at low (high) energy range. -- Abstract: We present first principle study of the electronic transport and dielectric properties of nanowires and nanoribbons of layered transition metal dichalcogenides (LTMDs), MX{sub 2} (M = Mo, W; X = S, Se, Te). The studied configuration shows metallic/semiconducting nature and the states around the Fermi energy are mainly contributed by the d orbitals of metal atoms. Zero-bias transmission show 1G{sub 0} conductance for the ribbons of MoS{sub 2} and WS{sub 2}; 2G{sub 0} conductance for MoS{sub 2}, WS{sub 2}, WSe{sub 2} wires, and ribbons of MoTe{sub 2} and WTe{sub 2}; and 3G{sub 0} conductance for WSe{sub 2} ribbon. The studied configurations show non-linear current–voltage (I–V) characteristics. Negative differential conductance (NDC) has also been observed for the nanoribbons of the selenides and tellurides of both Mo and W. Furthermore, additional plasmonic features below 5 eV energy have been observed for both wires and ribbons as compared to the corresponding monolayers, which is found to be red-shifted on going from nanowires to nanoribbons.

  9. Mastering energy transitions: a Franco-German project for growth

    International Nuclear Information System (INIS)

    Jamet, Jean-Francois; Lefebvre, Emmanuel

    2013-01-01

    If, to lay the foundations of the European Community of Steel and Coal (ECSC), the founding fathers of Europe had waited for the steelworks belonging to the Krupp family and the Creusot foundries to decide of their own accord to work closer together, the European Union would simply not have been created. Even today an ambitious European energy strategy cannot materialise unless it is supported by France and Germany. A political agreement is indeed necessary given the complexity of the market and the interplay of both public and private factors. Energy strategies in France and Germany have remained far too national, sometimes going as far as to diverge, which makes no sense in the context of European integration. The resulting incoherence has prevented the pooling of industrial investments at the very moment European energy markets are increasingly integrated and European industrialists are at risk of being outrun, both technologically and commercially, by their foreign competitors. On the occasion of the 50. anniversary of the Elysee Treaty France and Germany have tried to renew energy cooperation admitting that they face similar challenges in terms of energy transition and that they would have everything to gain by working together to rise to those challenges. Ideas were put forward which should be clarified, completed and made into a reality. Indeed there is a rare opportunity for a vast bilateral cooperation project consistent with the two countries' responsibility towards Europe. The objection over the disparity of energy choices between France and Germany, in terms of electricity production could be solved if we acknowledge that the markets and issues associated with energy transition extend beyond our national borders. Basically this means having quite an ambitious political vision of the constructive, coherent governance of energy transition. (authors)

  10. TANDEM - French-German cooperation for local energy transition

    International Nuclear Information System (INIS)

    Mouchard, Claire; Garreau, Enora; Maurer, Christiane; Schilken, Peter; Keilmann, Jenny-Claire; Janssen, Ulrike

    2014-01-01

    The simultaneous implementation of the German 'Energiewende' and the French 'Transition energetique' prompted both country's governments to sign various cooperation agreements. As both 'Energiewende' and 'Transition energetique' put a strong focus on decentralization of energy supply, establishing close inter-communal cooperation is particularly promising. The project TANDEM, which is jointly led by Klima-Buendnis and Energy Cities - both local authority networks - and co-funded by Germany's Federal Environment Agency (UBA) and the French Energy Agency ADEME provides French and German local authorities with a unique opportunity to exchange experiences and create partnerships for climate protection having the following objectives: - Creating broad mutual understanding for the respective situation, challenges and framework in energy and climate policy; - Encourage exchanges with regard to obstacles and success factors concerning the realization of ambitious energy- and climate-goals and promoting mutual transfer of know-how; - Stimulating close collaboration between local authorities from both countries while involving and supporting local stakeholders and citizens; - Implementing initial stages of cooperation projects during the lifetime of the TANDEM project and creating a foundation for long-term cooperation; - Raise awareness for demands, requirements and concerns of local authorities on a national and European level in order to strengthen their influence and enlarge their scope of action. In this document, the authors briefly present the French, German and European contexts and the organization of both countries regarding energy transition. Then, a parallel is made between the national energy-climate plans of both countries ('Klimaschutzkonzepte' and 'Plans Climat-Energie Territoriaux') to identify the similarities and differences in order to learn from each other and to be able to create cooperations between both policy mechanisms

  11. Mid-point review of the German energy transition

    International Nuclear Information System (INIS)

    Lauer, H.; Safa, H.; Guidez, J.

    2017-01-01

    The result of the 2015 review of the German energy transition is lukewarm. First: generating 20 % of the electricity production through wind power and solar energy appears to be very costly in Germany. Secondly there is practically no effect on the reduction of CO_2 releases as coal has been re-introduced to play the role of nuclear energy which was carbon-free to counter-balance the intermittency of renewable energies. Thirdly a necessity to keep all thermal plants ready to operate in order to cope with the intermittency of renewable energies as no adequate means of energy storage is available, appears to be a luxury that only Germany can afford. And fourthly, the cost of electric power for households and small enterprises is all the higher as the government economic policy is to spare German electro-intensive industry. One of the side effects of the German energy transition policy is to disturb the European market of electricity when favourable climate conditions make green electricity very abundant. In this situation electricity prices drop sharply and can even become negative while green electricity is always paid to the producer at a steady price guaranteed by the state. (A.C.)

  12. Energy efficiency throughout the world. On the way to transition

    International Nuclear Information System (INIS)

    Dessus, Benjamin; Laponche, Bernard; Blaustein, Edgar; Chappoz, Loic; Labrousse, Michel; Humberset, Suzanne; Peullemeulle, Justine; Magnin, Gerard; Lacassagne, Sylvie; Bertinat, Pablo; Soumaila, Ibrahim; Rialhe, Anne; Clain, Cristina; Poveda, Mentor; Scalambrini Coasta, Heitor; Diniz, Silvio; Osman, Nejib; Singh, Daljit; Sant, Girish; Kokino, Issairo; Methe Myrand, Lea; Raoust, Michel; Novel, Aymeric; Narain, Sunita; D'Monte, Darryl; Lopez, Jose; Mohanty, Brahmanand; Mezghani, Mohamed; Chamonin, Denis

    2012-10-01

    This document gathers several articles from different countries on different topics related to energy transition. The first part deals with the challenge of energy efficiency as a mean on the way to energy transition (in France, in Europe, in Latin America, in Asian developing countries). The second part illustrates through examples the importance of governance issues and political will (access to energy in West Africa, a network in Latin America and the Caribbean, use of LEDs for public lighting in Brazil, Tunisian policy, role of regulation authorities, situation in India). The third part proposes examples illustrating the importance of the local dimension in any policy aimed at energy efficiency (a project in Africa, public support in housing construction in Austin, the Swedish city of Vaxjo, the French city of Montdidier, the example of two quarters of Geneva using the lake water as cooling or heating source, the refrigerator fleet in a Palestinian village). The last part reports several experiments made in different sectors (building thermal rehabilitation in China, green buildings in India, the building sector in India, a new strategy in India for domestic and commercial electric equipment, stimulation of energy efficiency in the Japanese industry, public transport in sub-Saharan cities, energy efficiency in Indian agriculture)

  13. Growth and electronic structure of single-layered transition metal dichalcogenides

    DEFF Research Database (Denmark)

    Dendzik, Maciej

    2016-01-01

    only a weak interaction between SL MoS2 and graphene, which leads to a quasi-freestanding band structure, but also to the coexistence of multiple rotational domains. Measurements of SL WS2 on Ag(111), on the other hand, reveals formation of interesting in-gap states which make WS2 metallic. Low...... different from graphene’s. For example, semiconducting TMDCs undergo an indirectdirect band gap transition when thinned to a single layer (SL); this results in greatly enhanced photoluminescence, making those materials attractive for applications in optoelectronics. Furthermore, metallic TMDCs can host......-quality SL TMDCs. We demonstrate the synthesis of SL MoS2, WS2 and TaS2 on Au(111), Ag(111) and graphene on SiC. The morphology and crystal structure of the synthesized materials is characterized by scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED). The electronic structure of SL...

  14. Changing electronic density in sites of crystalline lattice under superconducting of phase transition

    International Nuclear Information System (INIS)

    Turaev, N.Yu.; Turaev, E.Yu.; Khuzhakulov, E.S.; Seregin, P.P.

    2006-01-01

    Results of electron density change calculations for sites of the one-dimensional Kronig-Penny lattice at the superconducting phase transition have been presented. The transition from normal state to super conducting one is accompanied by the rise of the electron density at the unit cell centre. It is agreement with Moessbauer spectroscopy data. (author)

  15. Facilitating energy transition through energy commons : An application of socio-ecological systems framework for integrated community energy systems

    NARCIS (Netherlands)

    Acosta, Cristina; Ortega, Mariana; Bunsen, Till; Koirala, B.P.; Ghorbani, A.

    2018-01-01

    Integrated Community Energy Systems (ICES) are an emerging local energy system focusing on the collective use of distributed energy resources (DER). These socio-technical systems (STSs) have a high potential to advance the transition towards socially inclusive, environmentally-friendly energy

  16. Facilitating energy transition through energy commons : An application of socio-ecological systems framework for integrated community energy systems

    NARCIS (Netherlands)

    Acosta, Cristina; Ortega, Mariana; Bunsen, Till; Koirala, Binod Prasad; Ghorbani, Amineh

    2018-01-01

    Integrated Community Energy Systems (ICES) are an emerging local energy system focusing on the collective use of distributed energy resources (DER). These socio-technical systems (STSs) have a high potential to advance the transition towards socially inclusive, environmentally-friendly energy

  17. To invest efficiently for a successful energy transition

    International Nuclear Information System (INIS)

    Beutier, Didier

    2017-01-01

    As the primary objective of any energy policy is now to reduce carbon dioxide emissions, i.e. to reduce the consumption of all carbonated fuels (coal, oil, gas) in all sectors, and to substitute them with electricity produced from nuclear and renewable sources, and all this under a double constraint (that of consumers, and that of public finances), this article aims at discussing whether the French policy defined by the law on energy transition for a green growth is able to face and meet these priorities. The author outlines that the struggle against greenhouse gas emissions in France mainly concerns the transport and heating sectors. He discusses drawbacks associated with a transition mainly focussed on electric power generation by wind and solar energy: these drawbacks concern the required and actual production level, necessary high investments, and the protection of the environment. He proposes four areas of development for a successful transition: electric transport, energy storage, power-to-gas conversion, and housing thermal insulation

  18. Transitions to improved core electron heat confinement in JT-II plasmas

    International Nuclear Information System (INIS)

    Estrada, T.; Medina, F.; Ascasibar, E.; Balbin, R.; Castejon, F.; Hidalgo, C.; Lopez-Bruna, D.; Petrov, S.

    2008-01-01

    Transitions to improved core electron heat confinement are triggered by low order rational magnetic surfaces in TJ-II ECH plasmas. Transitions triggered by the rational surface n=4/m=2 show an increase in the ion temperature synchronized with the increase in the electron temperature. SXR measurements demonstrate that, under certain circumstances, the rational surface positioned inside the plasma core region precedes and provides a trigger for the transition. (author)

  19. Conference on energy transition financing in France and Germany

    International Nuclear Information System (INIS)

    Faucheux, Ivan; Rid, Urban; Sickenberger, Peter; Ricordeau, Damien; Schmidt, Gerrit

    2014-01-01

    The French-German office for Renewable energies (OFAEnR) organised a conference on the energy transition financing in France and in Germany. In the framework of this French-German exchange of experience, participants exchanged views on the legal framework, the instruments and the role of financing institutions in the development of a low-carbon society and economy. Questions regarding the successful financing of renewable energy projects and the expectations of financiers were addressed. This document brings together the available presentations (slides) made during this event: 1 - Regulatory framework for investment in the 'green sector' in France (Ivan Faucheux); 2 - Overview of the financing framework for the German 'Energiewende' (Rid, Urban); 3 - Financing Renewables - KfW's Instruments and Track Record (Peter Sickenberger); 4 - French Overview on Renewable energy Financing (Damien Ricordeau); 5 - Profitability analysis of renewable energies in Germany: Which stakeholders and financing models have proven successful? (Gerrit Schmidt)

  20. Energy transition in France. A view of challenges and controversies. Proceedings of the first day, Friday 21 June 2013: Energy transition, society projects, and present tensions

    International Nuclear Information System (INIS)

    Billy, Isabelle; Ha-Duong, Minh; Finon, Dominique; Laugier, S.; Dollet, A.; Lecocq, F.; Bibas, R.; Hourcade, J.C.; Moisan, F.; Criqui, P.; Moncomble, J.E.; Salomon, T.; Bompart, J.P.; Crassous, Renaud; Geoffron, Patrice; Egenhofer, C.; Zachmann, G.; Baron, R.; Bussieras, M.; Salaun, Fabienne; Benassy-Quere, A.; Quirion, P.; Giraud, P.N.; Crifo, P.; Tutenuit, C.; Mestre, A.; Ghersi, Frederic; Bureau, D.; Giraud, G.; Lipietz, A.; Guivarch, Celine; Grubb, M.J.; Egenhofer, Christian; Watkinson, Paul; Lecocq, Franck

    2013-01-01

    The contributions of this meeting issues related to energy transition are proposed for different themes: decisions and objectives (a prospective study for energy transitions in France, comments on ADEME's transition scenarios and their micro-economic impacts, structuring scenarios, assessment criteria and blind points in energy transition, comments of French scenarios with respect to the prospective methodology of energy transition of the World Energy Council), market mechanisms in Europe (inner contradictions of European policies about market regime, low carbon policies and renewable energy policies, tension between the European regime of integrated electricity markets and the originality of national policies within the EU, designing energy transition in a member-state with or without taking European integration into account), energy, employment and growth modes (the impact of energy transition in France on jobs studied by means of an input-output analysis, energy transition as a re-balancing factor between nomadic and sedentary jobs, the impact of a green growth on jobs), financing transition and leaving stagnation, and the world transition towards a low carbon society (planetary economics, concepts and tools of transition and implications for European policy). The content of a round table and a synthesis are given for each of these themes

  1. Peak loads and network investments in sustainable energy transitions

    Energy Technology Data Exchange (ETDEWEB)

    Blokhuis, Erik, E-mail: e.g.j.blokhuis@tue.nl [Eindhoven University of Technology, Department of Architecture, Building and Planning, Vertigo 8.11, P.O. Box 513, 5600MB Eindhoven (Netherlands); Brouwers, Bart [Eindhoven University of Technology, Department of Architecture, Building and Planning, Vertigo 8.11, P.O. Box 513, 5600MB Eindhoven (Netherlands); Putten, Eric van der [Endinet, Gas and Electricity Network Operations, P.O. Box 2005, 5600CA Eindhoven (Netherlands); Schaefer, Wim [Eindhoven University of Technology, Department of Architecture, Building and Planning, Vertigo 8.11, P.O. Box 513, 5600MB Eindhoven (Netherlands)

    2011-10-15

    Current energy distribution networks are often not equipped for facilitating expected sustainable transitions. Major concerns for future electricity networks are the possibility of peak load increases and the expected growth of decentralized energy generation. In this article, we focus on peak load increases; the effects of possible future developments on peak loads are studied, together with the consequences for the network. The city of Eindhoven (the Netherlands) is used as reference city, for which a scenario is developed in which the assumed future developments adversely influence the maximum peak loads on the network. In this scenario, the total electricity peak load in Eindhoven is expected to increase from 198 MVA in 2009 to 591-633 MVA in 2040. The necessary investments for facilitating the expected increased peak loads are estimated at 305-375 million Euros. Based upon these projections, it is advocated that - contrary to current Dutch policy - choices regarding sustainable transitions should be made from the viewpoint of integral energy systems, evaluating economic implications of changes to generation, grid development, and consumption. Recently applied and finished policies on energy demand reduction showed to be effective; however, additional and connecting policies on energy generation and distribution should be considered on short term. - Highlights: > Sustainable energy transitions can result in major electricity peak load increases. > Introduction of heat pumps and electrical vehicles requires network expansion. > Under worst case assumptions, peak loads in Eindhoven increase with 200% until 2040. > The necessary investment for facilitating this 2040 peak demand is Euro 305-375 million. > Future policy choices should be made from the viewpoint of the integral energy system.

  2. Peak loads and network investments in sustainable energy transitions

    International Nuclear Information System (INIS)

    Blokhuis, Erik; Brouwers, Bart; Putten, Eric van der; Schaefer, Wim

    2011-01-01

    Current energy distribution networks are often not equipped for facilitating expected sustainable transitions. Major concerns for future electricity networks are the possibility of peak load increases and the expected growth of decentralized energy generation. In this article, we focus on peak load increases; the effects of possible future developments on peak loads are studied, together with the consequences for the network. The city of Eindhoven (the Netherlands) is used as reference city, for which a scenario is developed in which the assumed future developments adversely influence the maximum peak loads on the network. In this scenario, the total electricity peak load in Eindhoven is expected to increase from 198 MVA in 2009 to 591-633 MVA in 2040. The necessary investments for facilitating the expected increased peak loads are estimated at 305-375 million Euros. Based upon these projections, it is advocated that - contrary to current Dutch policy - choices regarding sustainable transitions should be made from the viewpoint of integral energy systems, evaluating economic implications of changes to generation, grid development, and consumption. Recently applied and finished policies on energy demand reduction showed to be effective; however, additional and connecting policies on energy generation and distribution should be considered on short term. - Highlights: → Sustainable energy transitions can result in major electricity peak load increases. → Introduction of heat pumps and electrical vehicles requires network expansion. → Under worst case assumptions, peak loads in Eindhoven increase with 200% until 2040. → The necessary investment for facilitating this 2040 peak demand is Euro 305-375 million. → Future policy choices should be made from the viewpoint of the integral energy system.

  3. Observation of strongly forbidden solid effect dynamic nuclear polarization transitions via electron-electron double resonance detected NMR

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Albert A.; Corzilius, Björn; Haze, Olesya; Swager, Timothy M.; Griffin, Robert G., E-mail: rgg@mit.edu [Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2013-12-07

    We present electron paramagnetic resonance experiments for which solid effect dynamic nuclear polarization transitions were observed indirectly via polarization loss on the electron. This use of indirect observation allows characterization of the dynamic nuclear polarization (DNP) process close to the electron. Frequency profiles of the electron-detected solid effect obtained using trityl radical showed intense saturation of the electron at the usual solid effect condition, which involves a single electron and nucleus. However, higher order solid effect transitions involving two, three, or four nuclei were also observed with surprising intensity, although these transitions did not lead to bulk nuclear polarization—suggesting that higher order transitions are important primarily in the transfer of polarization to nuclei nearby the electron. Similar results were obtained for the SA-BDPA radical where strong electron-nuclear couplings produced splittings in the spectrum of the indirectly observed solid effect conditions. Observation of high order solid effect transitions supports recent studies of the solid effect, and suggests that a multi-spin solid effect mechanism may play a major role in polarization transfer via DNP.

  4. Conformational Transitions and Convergence of Absolute Binding Free Energy Calculations

    Science.gov (United States)

    Lapelosa, Mauro; Gallicchio, Emilio; Levy, Ronald M.

    2011-01-01

    The Binding Energy Distribution Analysis Method (BEDAM) is employed to compute the standard binding free energies of a series of ligands to a FK506 binding protein (FKBP12) with implicit solvation. Binding free energy estimates are in reasonably good agreement with experimental affinities. The conformations of the complexes identified by the simulations are in good agreement with crystallographic data, which was not used to restrain ligand orientations. The BEDAM method is based on λ -hopping Hamiltonian parallel Replica Exchange (HREM) molecular dynamics conformational sampling, the OPLS-AA/AGBNP2 effective potential, and multi-state free energy estimators (MBAR). Achieving converged and accurate results depends on all of these elements of the calculation. Convergence of the binding free energy is tied to the level of convergence of binding energy distributions at critical intermediate states where bound and unbound states are at equilibrium, and where the rate of binding/unbinding conformational transitions is maximal. This finding mirrors similar observations in the context of order/disorder transitions as for example in protein folding. Insights concerning the physical mechanism of ligand binding and unbinding are obtained. Convergence for the largest FK506 ligand is achieved only after imposing strict conformational restraints, which however require accurate prior structural knowledge of the structure of the complex. The analytical AGBNP2 model is found to underestimate the magnitude of the hydrophobic driving force towards binding in these systems characterized by loosely packed protein-ligand binding interfaces. Rescoring of the binding energies using a numerical surface area model corrects this deficiency. This study illustrates the complex interplay between energy models, exploration of conformational space, and free energy estimators needed to obtain robust estimates from binding free energy calculations. PMID:22368530

  5. Simple solvable energy-landscape model that shows a thermodynamic phase transition and a glass transition.

    Science.gov (United States)

    Naumis, Gerardo G

    2012-06-01

    When a liquid melt is cooled, a glass or phase transition can be obtained depending on the cooling rate. Yet, this behavior has not been clearly captured in energy-landscape models. Here, a model is provided in which two key ingredients are considered in the landscape, metastable states and their multiplicity. Metastable states are considered as in two level system models. However, their multiplicity and topology allows a phase transition in the thermodynamic limit for slow cooling, while a transition to the glass is obtained for fast cooling. By solving the corresponding master equation, the minimal speed of cooling required to produce the glass is obtained as a function of the distribution of metastable states.

  6. Ab initio study of vibronic transitions between x2π and 12Σ+ electronic states of HCP+ ion

    Directory of Open Access Journals (Sweden)

    Stojanović Ljiljana

    2013-01-01

    Full Text Available The ground and low-lying excited doublet electronic states of the HCP+ ion were studied by means of multireference configuration interaction method. Vibronic energy levels of the X2Π state of Σ, Π, Δ, and Φ symmetry, up to the 2500 cm-1, have been calculated variationally, employing previously developed ab initio methods which take into account vibronic and spin-orbit interactions. Obtained vibronic wave functions were used to estimate transition moments between vibronic energy levels of the X2Π and 12Σ+ electronic states. Results were compared to available experimental and theoretical data. [Projekat Ministarstva nauke Republike Srbije, br. 172040

  7. Blockchain and energy transition - what challenges for cities?

    International Nuclear Information System (INIS)

    Donnerer, David; Lacassagne, Sylvie

    2018-02-01

    Energy blockchain experiments and pilots are multiplying, driven by tech-savvy entrepreneurs. It looks like the new technology is disrupting the energy system from Spain to the US. What is in it for cities? Energy Cities makes sense of the blockchain buzz with this publication. The blockchain is not just for techies: after stirring up financial markets through the virtual currency bitcoin, the blockchain technology is quickly conquering other industries and markets - notably energy. The energy sector has been undergoing radical transformations, from decentralization, new storage technologies to the advent of artificial intelligence in managing supply and demand. Can the disruptive blockchain technology support cities in tackling these drastic and quickly unfolding changes? In this study, Energy Cities deciphers the potential role of blockchain in the local energy transition. How does it work and what does it impact concretely? How can it be applied in local energy systems? What are the opportunities and threats associated with this new technology that local governments should know about? Can it strengthen cities' role in the energy market or will it entrench the reign of the dinosaur utilities? These questions are explored in this study, and a comprehensive overview of ongoing relevant blockchain energy projects for cities is given

  8. Cohesion and coordination effects on transition metal surface energies

    Science.gov (United States)

    Ruvireta, Judit; Vega, Lorena; Viñes, Francesc

    2017-10-01

    Here we explore the accuracy of Stefan equation and broken-bond model semiempirical approaches to obtain surface energies on transition metals. Cohesive factors are accounted for either via the vaporization enthalpies, as proposed in Stefan equation, or via cohesive energies, as employed in the broken-bond model. Coordination effects are considered including the saturation degree, as suggested in Stefan equation, employing Coordination Numbers (CN), or as the ratio of broken bonds, according to the bond-cutting model, considering as well the square root dependency of the bond strength on CN. Further, generalized coordination numbers CN bar are contemplated as well, exploring a total number of 12 semiempirical formulations on the three most densely packed surfaces of 3d, 4d, and 5d Transition Metals (TMs) displaying face-centered cubic (fcc), body-centered cubic (bcc), or hexagonal close-packed (hcp) crystallographic structures. Estimates are compared to available experimental surface energies obtained extrapolated to zero temperature. Results reveal that Stefan formula cohesive and coordination dependencies are only qualitative suited, but unadvised for quantitative discussion, as surface energies are highly overestimated, favoring in addition the stability of under-coordinated surfaces. Broken-bond cohesion and coordination dependencies are a suited basis for quantitative comparison, where square-root dependencies on CN to account for bond weakening are sensibly worse. An analysis using Wulff shaped averaged surface energies suggests the employment of broken-bond model using CN to gain surface energies for TMs, likely applicable to other metals.

  9. World nuclear atlas. A step toward energy transition

    International Nuclear Information System (INIS)

    Lepage, Corinne; Laborde, Xemartin

    2015-01-01

    Illustrated by more than 120 maps and figures, this book proposes an overview of the world nuclear industry, of its development, and of the various strategies chosen within the perspective of energy transition. It proposes an overview of the status of nuclear energy in the world (presentation of the nuclear energy, development during the X X century, uranium production, fuel production and processing, the nuclear reactor industry), addresses the main controversies (health and environmental impact, waste management, opacity of the information, major accidents), the new challenges faced by the nuclear sector (a difficult assessment of huge costs, competition with renewable energies, a competitive environment, a technological uncertainty, transparency and democracy), the solutions chosen by big countries (USA, China, India, Japan, Europe, the German energy transition), and proposes a focus on France which is the only country which chose an all-nuclear strategy (history, nuclear installations, main actors, the myth of the French energy independence, the post-Fukushima French fleet, the case of the Fessenheim reactor, the EPR in question, the challenge of waste storage with the Cigeo project, the debate on the nuclear cost)

  10. Tricritical behaviour in the phase transition induced by electron-hole pairing

    International Nuclear Information System (INIS)

    Crisan, M.

    1980-01-01

    The electron-hole pairing, which is possible in metals or semiconductors, can give condensed phases with two order parameters. If the coupling between the two order parameters is considered, the free energy functional is similar with the free energy of a n-component spin system with cubic anisotropy. Using the Wagner hypothesis (tricritical scaling) the non-linear scaling fields have been calculated. In order to perform the calculation of the nonlinear fields we used the method given by Rudnick and Nelson to solve the recursion relations for the 4-epsilon-dimensional system with n=6 components. The present calculation in the frame-work of the renormalization-group approach confirms the result obtained in the mean-field theory that the coupling of the two order parameters induces a first order phase transition. (author)

  11. Energy return on (energy) invested (EROI), oil prices, and energy transitions

    International Nuclear Information System (INIS)

    Heun, Matthew Kuperus; de Wit, Martin

    2012-01-01

    Very little work has been done so far to model, test, and understand the relationship between oil prices and EROI over time. This paper investigates whether a declining EROI is associated with an increasing oil price and speculates on the implications of these results on oil policy. A model of the relationship between EROI and oil market prices was developed using basic economic and physical assumptions and non-linear least-squares regression models to correlate oil production price with EROI using available data from 1954–1996. The model accurately reflects historical oil prices (1954–1996), and it correlates well with historical oil prices (1997–2010) if a linear extrapolation of EROI decline is assumed. As EROI declines below 10, highly non-linear oil price movements are observed. Increasing physical oil scarcity is already providing market signals that would stimulate a transition away from oil toward alternative energy sources. But, price signals of physical oil scarcity are not sufficient to guarantee smooth transitions to alternative fuel sources, especially when there is insufficient oil extraction technology development, a declining mark-up ratio, a non-linear EROI–cost of production relationship, and a non-linear EROI–price relationship. - Highlights: ► A model of the relationship between EROI and oil prices has been developed. ► As EROI declines below 10, highly non-linear oil price movements are expected. ► Physical oil scarcity provides market signals for a transition to alternatives. ► Scarcity price signals are insufficient for smooth transitions to alternatives.

  12. Strongly correlated electron systems and neutron scattering. Magnetism, superconductivity, structural phase transition

    Energy Technology Data Exchange (ETDEWEB)

    Katano, Susumu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    Neutron scattering experiments in our group on strongly correlated electron systems are reviewed Metal-insulator transitions caused by structural phase transitions in (La{sub 1-x}Sr{sub x}) MnO{sub 3}, a novel magnetic transition in the CeP compound, correlations between antiferromagnetism and superconductivity in UPd{sub 2}Al{sub 3} and so forth are discussed. Here, in this note, the phase transition of Mn-oxides was mainly described. (author)

  13. The Energy transition for green growth. Energy transition for green growth act in action: Regions - Citizens - Business

    International Nuclear Information System (INIS)

    2016-07-01

    A great ambition underlies France's Energy Transition for Green Growth Act: to make France - following on from the Paris Climate Summit - an exemplary nation in terms of reducing its greenhouse gas emissions, diversifying its energy model and increasing the deployment of renewable energy sources. This Act provides a unique opportunity both for climate negotiations and for France. It sets goals and implements operational solutions which can be shared with different regions, companies, researchers, the public and anyone with a long-standing commitment to fighting climate change. The Energy Transition for Green Growth Act and its attendant action plans are designed to give France the means to make a more effective contribution to tackling climate change and reinforce its energy independence, while striking a better balance in its energy mix and creating jobs and business growth. The texts required for its implementation are operational and support plans are in place. These tools are available to private individuals, businesses and the regions, enabling them to take concrete action. This document summarizes the actions under way: Defining common objectives, Acting together, Renovating buildings, developing clean transport, Tackling waste and promoting the circular economy, Promoting renewable energy, optimising nuclear safety and public information, Simplifying and clarifying procedures

  14. R and D and Innovation, Drivers of Energy Transition

    International Nuclear Information System (INIS)

    Eudes Moncomble, J.

    2016-01-01

    After a brief review of the decisive contribution of the R and D and the innovation (RDI) to the economic growth and thus to the employment and also as a main driver of energy transition in Europe, a focus will be brought in how RDI choices are made, especially in companies, with the consequences on the business organization. Focusing on the conditions of the deployment and the dissemination of innovations, the key role of the demonstration will be examined as well as the learnings to promote the emergence of new technologies, particularly those serving the energy transition. In conclusion, we will discuss how the research and innovation policies are being addressed, in particular their connection with corporate strategies and industrial policies? All along the presentation, several examples of different technologies will be given, in order to provide illustrations of the potential developments, the possible breakthroughs, bottlenecks and cost etc.(author).

  15. Energy Budget of Cosmological First-order Phase Transitions

    CERN Document Server

    Espinosa, Jose R; No, Jose M; Servant, Geraldine

    2010-01-01

    The study of the hydrodynamics of bubble growth in first-order phase transitions is very relevant for electroweak baryogenesis, as the baryon asymmetry depends sensitively on the bubble wall velocity, and also for predicting the size of the gravity wave signal resulting from bubble collisions, which depends on both the bubble wall velocity and the plasma fluid velocity. We perform such study in different bubble expansion regimes, namely deflagrations, detonations, hybrids (steady states) and runaway solutions (accelerating wall), without relying on a specific particle physics model. We compute the efficiency of the transfer of vacuum energy to the bubble wall and the plasma in all regimes. We clarify the condition determining the runaway regime and stress that in most models of strong first-order phase transitions this will modify expectations for the gravity wave signal. Indeed, in this case, most of the kinetic energy is concentrated in the wall and almost no turbulent fluid motions are expected since the s...

  16. Sanitation methods using high energy electron beams

    International Nuclear Information System (INIS)

    Levaillant, C.; Gallien, C.L.

    1979-01-01

    Short recycling of waste water and the use of liquid or dehydrated sludge as natural manure for agriculture or animal supplement feed is of great economical and ecological interest. It implies strong biological and chemical disinfection. Ionizing radiations produced by radioactive elements or linear accelerators can be used as a complement of conventional methods in the treatment of liquid and solid waste. An experiment conducted with high-energy electron-beam linear accelerators is presented. Degradation of undesirable metabolites in water occurs for a dose of 50 kRad. Undesirable seeds present in sludge are destroyed with a 200 kRad dose. A 300 kRad dose is sufficient for parasitic and bacterial disinfection (DL 90). Destruction of polio virus (DL 90) is obtained for 400 kRad. Higher doses (1000 to 2000 kRad) produce mineralization of toxic organic mercury, reduce some chemical toxic pollutants present in sludge and improve flocculation. (author)

  17. Benchmarking NaI(Tl) Electron Energy Resolution Measurements

    International Nuclear Information System (INIS)

    Mengesha, Wondwosen; Valentine, J D.

    2002-01-01

    A technique for validating electron energy resolution results measured using the modified Compton coincidence technique (MCCT) has been developed. This technique relies on comparing measured gamma-ray energy resolution with calculated values that were determined using the measured electron energy resolution results. These gamma-ray energy resolution calculations were based on Monte Carlo photon transport simulations, the measured NaI(Tl) electron response, a simplified cascade sequence, and the measured electron energy resolution results. To demonstrate this technique, MCCT-measured NaI(Tl) electron energy resolution results were used along with measured gamma-ray energy resolution results from the same NaI(Tl) crystal. Agreement to within 5% was observed for all energies considered between the calculated and measured gamma-ray energy resolution results for the NaI(Tl) crystal characterized. The calculated gamma-ray energy resolution results were also compared with previously published gamma-ray energy resolution measurements with good agreement (<10%). In addition to describing the validation technique that was developed in this study and the results, a brief review of the electron energy resolution measurements made using the MCCT is provided. Based on the results of this study, it is believed that the MCCT-measured electron energy resolution results are reliable. Thus, the MCCT and this validation technique can be used in the future to characterize the electron energy resolution of other scintillators and to determine NaI(Tl) intrinsic energy resolution

  18. Search for $\\beta$-transitions with the lowest decay energy for a determination of the neutrino mass

    CERN Multimedia

    From a variety of $\\beta$-transitions only those with decay energies of a few keV and smaller are considered suitable for a determination of the neutrino mass on a sub-eV level. The decay energy of a transition can be very small, if, e.g., in an allowed $\\beta$-decay or electron-capture transition, a nuclear excited state of the daughter nuclide is populated whose energy is very close to the mass difference of the transition nuclides. Investigation of these transitions can also be useful for the assessment of a validity of the current $\\beta$-decay theory in the region of vanishingly small decay energies. The authors of this proposal have found several such $\\beta$-transitions whose decay energies are expected to be extremely small. In order to assess the suitability of these $\\beta$-transitions for the determination of the neutrino mass, measurements of the mass differences of the transition nuclides must be carried out with a sub-keV uncertainty. Presently, only high-precision Penning-trap mass spectrometry...

  19. Building concepts for a transition towards energy neutrality in 2050

    Energy Technology Data Exchange (ETDEWEB)

    De Boer, B.J.; Paauw, J. [TNO Built Environment and Geosciences, Delft (Netherlands); Opstelten, I.J.; Bakker, E.J. [Energy research Centre of the Netherlands ECN, Petten (Netherlands)

    2007-03-15

    In this paper building concepts for the near future are described which enable the transition towards a net energy neutral building sector in the Netherlands by the year 2050. With 'net energy neutrality' is meant that, on a yearly basis, the total energy consumption in the built environment is compensated by local renewable energy production e.g. by using solar thermal (T), photovoltaic (PV), PVT and/or wind. A study concerning the feasibility of a 'net energy neutral built environment by 2050' set the energetic ambitions for the building concepts to be developed. This resulted in different concepts for residential buildings and for office-buildings. The building concepts are based on passive house technology to minimise the heating and cooling demand, and make optimal use of active and passive solar energy. Concepts for new to build domestic buildings are in fact energy producing to compensate for the remaining energy demand of existing, renovated dwellings. In all concepts the 'trias energetica' or 'energy pyramid' served as a general guideline, striving for minimisation of energy demand, maximal usage of renewable energy and usage of fossil fuels as efficiently as possible. Different full roof integrated options for using solar energy (PV, T or PVT) with variable storage options have been compared by making simulations with a dynamic simulation programme, to gain insight on their impact on energy, building engineering and economic impact. Also different possibilities for installations to fulfil the heating demand for the space heating and DHW demand are compared. For each concept, the resulting primary energy profiles for space heating and cooling, domestic hot water, electricity consumption for lighting, ventilation and household appliances are given.

  20. Surface characterization by energy distribution measurements of secondary electrons and of ion-induced electrons

    International Nuclear Information System (INIS)

    Bauer, H.E.; Seiler, H.

    1988-01-01

    Instruments for surface microanalysis (e.g. scanning electron or ion microprobes, emission electron or ion microscopes) use the current of emitted secondary electrons or of emitted ion-induced electrons for imaging of the analysed surface. These currents, integrating over all energies of the emitted low energy electrons, are however, not well suited to surface analytical purposes. On the contrary, the energy distribution of these electrons is extremely surface-sensitive with respect to shape, size, width, most probable energy, and cut-off energy. The energy distribution measurements were performed with a cylindrical mirror analyser and converted into N(E), if necessary. Presented are energy spectra of electrons released by electrons and argon ions of some contaminated and sputter cleaned metals, the change of the secondary electron energy distribution from oxidized aluminium to clean aluminium, and the change of the cut-off energy due to work function change of oxidized aluminium, and of a silver layer on a platinum sample. The energy distribution of the secondary electrons often shows detailed structures, probably due to low-energy Auger electrons, and is broader than the energy distribution of ion-induced electrons of the same object point. (author)

  1. Transit investments for greenhouse gas and energy reduction program : second assessment report.

    Science.gov (United States)

    2014-08-01

    This report is the second assessment of the U.S. Department of Transportation, Federal Transit Administrations Transit Investments for : Greenhouse Gas and Energy Reduction (TIGGER) Program. The TIGGER Program provides capital funds to transit age...

  2. Molecularly Stretchable Electronics for Energy and Healthcare

    Science.gov (United States)

    Lipomi, Darren

    The term ``plastic electronics'' masks the wide range of mechanical behavior possessed by films of π-conjugated (semiconducting) small molecules and polymers. Such materials are promising for biosensors, large-area displays, low-energy lighting, and low-cost photovoltaic modules. There is also an apparent trade-off between electronic performance and mechanical compliance in films of some of the best-performing semiconducting polymers, which fracture at tensile strains not significantly greater than those at which conventional inorganic semiconductors fail. The design of intrinsically deformable electronic materials-i.e., imagine a semiconducting rubber band-would facilitate roll-to-roll production, mechanical robustness for potable applications, and conformal bonding to curved surfaces. This seminar describes my group's efforts to understand and control the structural parameters that influence the mechanical properties of π-conjugated polymers. The techniques we employ include synthetic chemistry, spectroscopy and microstructural characterization, computation from the molecular to continuum level, and electrical measurements of devices. A complex picture emerges for the interplay between molecular structure, the way the process of solidification influences the morphology, and how molecular structure and morphology combine to produce a film with a given modulus, elastic range, ductility, and toughness. We are also exploring ways to introduce other properties into organic semiconductors that are inspired by biological tissue. That is, not just elasticity and toughness, but also biodegradability and the capacity for self-repair. The seminar will also touch on our use of self-assembled metallic nanoislands on graphene for ultra-sensitive mechanical sensing using piezoresistive and ``piezoplasmonic'' mechanisms. The applications for these materials are in detecting human motion and measuring the mechanics of cardiac and musculoskeletal cells. My group is broadly

  3. Energy transition: the role of the gas vector

    International Nuclear Information System (INIS)

    Renard, Suzanne; Mazzega, Anthony

    2013-01-01

    GrDF (Gaz de France network Distribution) takes on all the responsibility functions - technical, industrial and legal - for a natural gas distribution network of almost 200 000 km, the most extensive in Europe. In the course of France's national debate on energy transition, GrDF presented its scenario out to 2050. One of its main conclusions: gas infrastructures can play a major role, accommodating new production, while ensuring solidarity between regions. (authors)

  4. Energy transformation in molecular electronic systems

    International Nuclear Information System (INIS)

    Kasha, M.

    1985-01-01

    Our new optical pumping spectroscopy (steady state, and double-laser pulse) allows the production and study of the unstable rare tautomer in its ground and excited states, including picosecond dynamic studies. Molecules under study here included 7-azaindole (model for biological purines), 3-hydroxyflavone (model for plant flavones), lumichrome, and other heterocyclics. New detailed molecular mechanisms for proton transfer are derived, especially with catalytic assisting molecules. A new proton-transfer laser of extraordinary efficiency has become a side dividend, possibly worth of industrial development. The excited and highly reactive singlet molecular oxygen species 1 Δ/sub g/) has proven to be ubiquitous in chemical peroxide systems and in physically excited sensitizer-oxygen systems. Hyperbaric oxygen mechanisms in biology probably involve singlet oxygen. We have undertaken a spectroscopic study of tris - dibenzoylmethane chelates of Al, Gd, Eu, and Yb trivalent ions. These chelates offer a variety of electronic behaviors, from Z-effects on π-electron spin-orbital coupling (Al, Gd) to Weissman intramolecular energy transfer to 4f mestable levels (Eu, Gd). Elegant new spectroscopic resolution at 77K permits separation of tautomeric, parasitic self-absorption, dissociation, and cage effects to be resolved. 18 refs., 4 figs

  5. Metal-insulator transition in one-dimensional lattices with chaotic energy sequences

    International Nuclear Information System (INIS)

    Pinto, R.A.; Rodriguez, M.; Gonzalez, J.A.; Medina, E.

    2005-01-01

    We study electronic transport through a one-dimensional array of sites by using a tight binding Hamiltonian, whose site-energies are drawn from a chaotic sequence. The correlation degree between these energies is controlled by a parameter regulating the dynamic Lyapunov exponent measuring the degree of chaos. We observe the effect of chaotic sequences on the localization length, conductance, conductance distribution and wave function, finding evidence of a metal-insulator transition (MIT) at a critical degree of chaos. The one-dimensional metallic phase is characterized by a Gaussian conductance distribution and exhibits a peculiar non-selfaveraging

  6. Metal-insulator transition in one-dimensional lattices with chaotic energy sequences

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, R.A. [Laboratorio de Fisica Estadistica, Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020-A (Venezuela)]. E-mail: ripinto@ivic.ve; Rodriguez, M. [Laboratorio de Fisica Estadistica, Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020-A (Venezuela); Gonzalez, J.A. [Laboratorio de Fisica Computacional, Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020-A (Venezuela); Medina, E. [Laboratorio de Fisica Estadistica, Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020-A (Venezuela)

    2005-06-20

    We study electronic transport through a one-dimensional array of sites by using a tight binding Hamiltonian, whose site-energies are drawn from a chaotic sequence. The correlation degree between these energies is controlled by a parameter regulating the dynamic Lyapunov exponent measuring the degree of chaos. We observe the effect of chaotic sequences on the localization length, conductance, conductance distribution and wave function, finding evidence of a metal-insulator transition (MIT) at a critical degree of chaos. The one-dimensional metallic phase is characterized by a Gaussian conductance distribution and exhibits a peculiar non-selfaveraging.

  7. On the electron density localization in elemental cubic ceramic and FCC transition metals by means of a localized electrons detector.

    Science.gov (United States)

    Aray, Yosslen; Paredes, Ricardo; Álvarez, Luis Javier; Martiz, Alejandro

    2017-06-14

    The electron density localization in insulator and semiconductor elemental cubic materials with diamond structure, carbon, silicon, germanium, and tin, and good metallic conductors with face centered cubic structure such as α-Co, Ni, Cu, Rh, Pd, Ag, Ir, Pt, and Au, was studied using a localized electrons detector defined in the local moment representation. Our results clearly show an opposite pattern of the electron density localization for the cubic ceramic and transition metal materials. It was found that, for the elemental ceramic materials, the zone of low electron localization is very small and is mainly localized on the atomic basin edges. On the contrary, for the transition metals, there are low-valued localized electrons detector isocontours defining a zone of highly delocalized electrons that extends throughout the material. We have found that the best conductors are those in which the electron density at this low-value zone is the lowest.

  8. Energy and population: transitional issues and eventual limits.

    Science.gov (United States)

    Werbos, P J

    1990-08-01

    The implication of population size for US energy requirements is explored in this essay. The basic argument is that the present supply of fuels and energy technologies is not sustainable in the long run, that a wide range of choices is possible when a complete transition is made to sustainable technologies, and that the growth of population and the composition of this growth during the next 30 years are the most serious problems impacting on the achievement of sustainable technology. The importance and future of fuel oil is discussed as well as the transition to sustainable energy supplies: conservation, renewables, nuclear and coal. Dependency on oil can only be changed through time and the infusion of money, but even with these givens, the transition is also dependent on the political and budgetary climate. The race is between crisis and cure. It is argued that the soft energy systems (biomass, solar water heater, wind, hydro, and geothermal energy) along with conservation will increase easily and naturally, but the total potential from these sources amounts to only 10% of the present US energy supply. Conservation offers greater hope because 80% of end-use fossil fuel is used in transportation and industry. Further growth of the population in the US would create a demand to desalinate water, which would increase the demand for energy. A totally soft energy economy is probably not feasible without a drastic reduction in US population. The expected direction is in the increased use of coal, and then nuclear energy. Unfortunately, coal contributes to greenhouse warming, and the supply is limited to 60-100 years. Nuclear proliferation and terrorism is connected to the widespread use of nuclear energy. Some breakthrough technology with cold fusion may offer a safer alternative. High technology renewables such as solar cells can be competitive with nuclear energy, if prices can be kept down. on earth or in space, are being investigated. Exploring a variety of advanced

  9. Low-energy electron emitters for targeted radiotherapy of small tumours

    International Nuclear Information System (INIS)

    Bernhardt, Peter; Forssell-Aronsson, Eva; Jacobsson, Lars; Skarnemark, Gunnar

    2001-01-01

    The possibility of using electron emitters to cure a cancer with metastatic spread depends on the energy of the emitted electrons. Electrons with high energy will give a high, absorbed dose to large tumours, but the absorbed dose to small tumours or single tumour cells will be low, because the range of the electrons is too long. The fraction of energy absorbed within the tumour decreases with increasing electron energy and decreasing tumour size. For tumours smaller than 1 g, the tumour-to-normal-tissue mean absorbed dose-rate ratio, TND, will be low, e.g. for 131 I and 90 Y, because of the high energy of the emitted electrons. For radiotherapy of small tumours, radionuclides emitting charged particles with short ranges (a few m u m ) are required. A mathematical model was constructed to evaluate the relation between TND and electron energy, photon-to-electron energy ratio, p/e, and tumour size. Criteria for the selection of suitable radionuclides for the treatment of small tumours were defined based on the results of the TND model. In addition, the possibility of producing such radionuclides and their physical and chemical properties were evaluated. Based on the mathematical model, the energy of the emitted electrons should be = 40 keV for small tumours ( 58m Co, 103m Rh, 119 Sb, 161 Ho, and 189m Os. All of these nuclides by internal transition or electron capture, which yields conversion and Auger electrons, and it should be possible to produce most of them in therapeutic amounts. The five low-energy electron-emitting radionuclides identified may be relevant in the radiation treatment of small tumours, especially if bound to internalizing radiopharmaceuticals

  10. Hydroelectricity: an asset for a successful energy transition in France

    International Nuclear Information System (INIS)

    Galland, J.C.; Vincent, E.

    2013-01-01

    France's national debate on energy transition has served as a reminder that hydroelectric power plays a significant role in French electricity production. With installed power totalling 25400 MW at end 2012 (the second largest in Europe), France's hydroelectric plants produced 63.8 TWh last year (the third largest in Europe), almost 12% of total output. It is France's second largest means of producing electricity and it represents more than 80% of production of renewable energy. A source of energy developed a long time ago, thus benefiting from technological maturity, hydroelectricity can be produced in large quantity at the heart of France's regions, while also rendering indispensable service for the equilibrium of the French electricity system by compensating the intermittency of other renewable energy sources. The production costs of hydroelectric power are the lowest among all power generation technologies. (authors)

  11. Energy transition: from national scenarios to European policies

    International Nuclear Information System (INIS)

    Mathieu, Mathilde

    2013-01-01

    This thesis aims at seeing how an analysis of national scenarios of energy transition may contribute to the elaboration of European energy and climate policies. The author first identifies the characteristics of energy scenarios, and the relationship between a scenario considered as an object on the one hand, and a vision for the long term on the other hand. She proposes an analysis framework which enables a comparative analysis of scenarios in order to identify stakes and challenges for the future European policy. In the second part, the author presents three examples (Germany, United Kingdom and France) and discusses their political context and adopted scenarios. After an overview of existing European energy and climate policies, the results of the analysis are given for two specific sectors: transports and electricity

  12. Laser pulse propagation and enhanced energy coupling to fast electrons in dense plasma gradients

    International Nuclear Information System (INIS)

    Gray, R J; Carroll, D C; Yuan, X H; Brenner, C M; Coury, M; Quinn, M N; Tresca, O; McKenna, P; Burza, M; Wahlström, C-G; Lancaster, K L; Neely, D; Lin, X X; Li, Y T

    2014-01-01

    Laser energy absorption to fast electrons during the interaction of an ultra-intense (10 20 W cm −2 ), picosecond laser pulse with a solid is investigated, experimentally and numerically, as a function of the plasma density scale length at the irradiated surface. It is shown that there is an optimum density gradient for efficient energy coupling to electrons and that this arises due to strong self-focusing and channeling driving energy absorption over an extended length in the preformed plasma. At longer density gradients the laser filaments, resulting in significantly lower overall energy coupling. As the scale length is further increased, a transition to a second laser energy absorption process is observed experimentally via multiple diagnostics. The results demonstrate that it is possible to significantly enhance laser energy absorption and coupling to fast electrons by dynamically controlling the plasma density gradient. (paper)

  13. Spectral measurements of few-electron uranium ions produced and trapped in a high-energy electron beam ion trap

    International Nuclear Information System (INIS)

    Beiersdorfer, P.

    1994-01-01

    Measurements of 2s l/2 -2p 3/2 electric dipole and 2p 1/2 -2p 3/2 magnetic dipole and electric quadrupole transitions in U 82+ through U 89+ have been made with a high-resolution crystal spectrometer that recorded the line radiation from stationary ions produced and trapped in a high-energy electron beam ion trap. From the measurements we infer -39.21 ± 0.23 eV for the QED contribution to the 2s 1/2 -2p 3/2 transition energy of lithiumlike U 89+ . A comparison between our measurements and various computations illustrates the need for continued improvements in theoretical approaches for calculating the atomic structure of ions with two or more electrons in the L shell

  14. Energy transitions in France: lessons learned from prospective studies. Contribution to the National Debate on Energy Transition

    International Nuclear Information System (INIS)

    Bibas, Ruben; Hourcade, Jean-Charles

    2013-01-01

    After having outlined that the debates on energy transition in France focus on three main issues (management of greenhouse gas emissions, future of nuclear within the French energy mix, energy security), the authors report the use of the Imaclim-R France model (a multi-sector recursive hybrid model) which is adapted to sensitivity studies for the whole set of hypotheses. As energy parameters, they use data provided by ENCILOWCARB scenarios from a European project (Engaging civil society in low carbon scenarios). After having examined that they are not sufficient to conduct a transition strategy leading to a F4 pathway of reduction of greenhouse gas emissions and/or a progressive phasing out nuclear, they consider the policies which are necessary to mobilise potentials of energy saving and emission reduction. Several scenarios are studied in terms of energy and environmental performances and in terms of economic and social performances: scenarios based on policies and measures with or without additional component (carbon tax, social negotiation, carbon finance)

  15. Electronic and magnetic properties of 3d transition metal-doped strontium clusters: Prospective magnetic superatoms

    International Nuclear Information System (INIS)

    Chauhan, Vikas; Sen, Prasenjit

    2013-01-01

    Highlights: • Structural, electronic and magnetic properties of TM-Sr clusters are studied using DFT methods. • CrSr 9 and MnSr 10 have enhanced stability in the CrSr n and MnSrn series. • These two clusters behave as magnetic superatoms. • A qualitative understanding of the magnetic coupling between two superatom units is offered. • Reactivity of these superatoms to molecular oxygen also studied. - Abstract: Structural, electronic and magnetic properties of 3d transition metal doped strontium clusters are studied using first-principles electronic structure methods based on density functional theory. Clusters with enhanced kinetic and thermodynamic stability are identified by studying their hardness, second order energy difference and adiabatic spin excitation energy. CrSr 9 and MnSr 10 are found to have enhanced stability. They retain their structural identities in assemblies, and are classified as magnetic superatoms. A qualitative understanding of the magnetic coupling between two cluster units is arrived at. Reactivity of these superatoms with O 2 molecule is also studied. Prospects for using these magnetic superatoms in applications are discussed

  16. The interaction of low-energy electrons with fructose molecules

    Science.gov (United States)

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

    2017-11-01

    Using a hypocycloidal electronic spectrometer, the interactions of low energy electrons (0-8.50 eV) with fructose molecules, namely, electron scattering and dissociative attachment, are studied. The results of these studies showed that the fragmentation of fructose molecules occurs effectively even at an electron energy close to zero. In the total electron-scattering cross section by molecules, resonance features (at energies 3.10 and 5.00 eV) were first observed near the formation thresholds of light ion fragments OH- and H-. The correlation of the features observed in the cross sections of electron scattering and dissociative attachment is analyzed.

  17. Equation satisfied by electron-electron mutual Coulomb repulsion energy density functional

    OpenAIRE

    Joubert, Daniel P.

    2011-01-01

    The electron-electron mutual Coulomb repulsion energy density functional satisfies an equation that links functionals and functional derivatives at N-electron and (N-1)-electron densities for densities determined from the same adiabatic scaled external potential for the N-electron system.

  18. Development of a secondary electron energy analyzer for a transmission electron microscope.

    Science.gov (United States)

    Magara, Hideyuki; Tomita, Takeshi; Kondo, Yukihito; Sato, Takafumi; Akase, Zentaro; Shindo, Daisuke

    2018-04-01

    A secondary electron (SE) energy analyzer was developed for a transmission electron microscope. The analyzer comprises a microchannel plate (MCP) for detecting electrons, a coil for collecting SEs emitted from the specimen, a tube for reducing the number of backscattered electrons incident on the MCP, and a retarding mesh for selecting the energy of SEs incident on the MCP. The detection of the SEs associated with charging phenomena around a charged specimen was attempted by performing electron holography and SE spectroscopy using the energy analyzer. The results suggest that it is possible to obtain the energy spectra of SEs using the analyzer and the charging states of a specimen by electron holography simultaneously.

  19. The future of transportation in sustainable energy systems: Opportunities and barriers in a clean energy transition

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo; Bačeković, Ivan; Pedersen, Allan Schrøder

    2017-01-01

    Energy demand of a transport sector has constantly been increasing in the recent years, consuming one third of the total final energy demand in the European Union (EU) over the last decade. A transition of this sector towards sustainable one is facing many challenges in terms of suitable technolo...

  20. Sustainable energy for the future. Modelling transitions to renewable and clean energy in rapidly developing countries.

    NARCIS (Netherlands)

    Urban, Frauke

    2009-01-01

    The main objective of this thesis is first to adapt energy models for the use in developing countries and second to model sustainable energy transitions and their effects in rapidly developing countries like China and India. The focus of this thesis is three-fold: a) to elaborate the differences

  1. Sustainable Energy United in Diversity: Challenges and Approaches in Energy Transition in the EU

    NARCIS (Netherlands)

    Squintani, Lorenzo; Vedder, Hans; Vanheusden, Bernard; Reese, Moritz

    2014-01-01

    This book focuses on the relationship between environmental protection and the production, distribution and consumption of energy and the regulatory and policy challenges that are felt in the transition to a sustainable energy system and more generally a low carbon economy. Today, an increasingly

  2. 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

  3. Study and realization of an electron gun at low energy

    International Nuclear Information System (INIS)

    Camus, P.

    1977-01-01

    This work presents the theoretical concepts and experimental design of an electron gun. This gun is working in the weak energy range and the focus position is independant of electron energy measurements and analysis methods of the electron beam are described [fr

  4. Modified electron acoustic field and energy applied to observation data

    Energy Technology Data Exchange (ETDEWEB)

    Abdelwahed, H. G., E-mail: hgomaa-eg@yahoo.com, E-mail: hgomaa-eg@mans.edu.eg [College of Science and Humanitarian Studies, Physics Department, Prince Sattam Bin Abdul Aziz University, Alkharj 11942 (Saudi Arabia); Theoretical Physics Research Group, Physics Department, Faculty of Science, Mansoura University, Mansoura 35516 (Egypt); El-Shewy, E. K. [Theoretical Physics Research Group, Physics Department, Faculty of Science, Mansoura University, Mansoura 35516 (Egypt)

    2016-08-15

    Improved electrostatic acoustic field and energy have been debated in vortex trapped hot electrons and fluid of cold electrons with pressure term plasmas. The perturbed higher-order modified-Korteweg-de Vries equation (PhomKdV) has been worked out. The effect of trapping and electron temperatures on the electro-field and energy properties in auroral plasmas has been inspected.

  5. Absorbing phase transitions in deterministic fixed-energy sandpile models

    Science.gov (United States)

    Park, Su-Chan

    2018-03-01

    We investigate the origin of the difference, which was noticed by Fey et al. [Phys. Rev. Lett. 104, 145703 (2010), 10.1103/PhysRevLett.104.145703], between the steady state density of an Abelian sandpile model (ASM) and the transition point of its corresponding deterministic fixed-energy sandpile model (DFES). Being deterministic, the configuration space of a DFES can be divided into two disjoint classes such that every configuration in one class should evolve into one of absorbing states, whereas no configurations in the other class can reach an absorbing state. Since the two classes are separated in terms of toppling dynamics, the system can be made to exhibit an absorbing phase transition (APT) at various points that depend on the initial probability distribution of the configurations. Furthermore, we show that in general the transition point also depends on whether an infinite-size limit is taken before or after the infinite-time limit. To demonstrate, we numerically study the two-dimensional DFES with Bak-Tang-Wiesenfeld toppling rule (BTW-FES). We confirm that there are indeed many thresholds. Nonetheless, the critical phenomena at various transition points are found to be universal. We furthermore discuss a microscopic absorbing phase transition, or a so-called spreading dynamics, of the BTW-FES, to find that the phase transition in this setting is related to the dynamical isotropic percolation process rather than self-organized criticality. In particular, we argue that choosing recurrent configurations of the corresponding ASM as an initial configuration does not allow for a nontrivial APT in the DFES.

  6. Saturated bonds and anomalous electronic transport in transition-metal aluminides

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, T.

    2006-05-22

    This thesis deals with the special electronic properties of the transition-metal aluminides. Following quasicrystals and their approximants it is shown that even materials with small elementary cells exhibit the same surprising effects. So among the transition-metal aluminides also semi-metallic and semiconducting compounds exist, although if they consist of classic-metallic components like Fe, Al, or Cr. These properties are furthermore coupled with a deep pseusogap respectively gap in the density of states and strongly covalent bonds. Bonds are described in this thesis by two eseential properties. First by the bond charge and second by the energetic effect of the bond. It results that in the caes of semiconducting transition-metal aluminides both a saturation of certain bonds and a bond-antibond alteration in the Fermi level is present. By the analysis of the near-order in form of the so-calles coordination polyeders it has been succeeded to establish a simple rule for semiconductors, the five-fold coordination for Al. This rule states that aluminium atoms with their three valence electrons are not able to build more than five saturated bonds to their nearest transition-metal neighbours. In excellent agreement with the bond angles predicted theoretically under assumption of equal-type bonds it results that all binary transition-element aluminide semiconductors exhibit for the Al atoms the same near order. Typical values for specific resistances of the studied materials at room temperature lie in the range of some 100 {mu}{omega}cm, which is farly larger than some 10 {mu}{omega}cm as in the case of the unalloyed metals. SUrprising is furthermore a high transport anisotropy with a ratio of the specific resistances up to 3.0. An essential result of this thesis can be seen in the coupling of the properties of the electronic transport and the bond properties. The small conducitivities could be explained by small values in the density of states and a bond

  7. Photon and electron collimator effects on electron output and abutting segments in energy modulated electron therapy

    International Nuclear Information System (INIS)

    Olofsson, Lennart; Karlsson, Magnus G.; Karlsson, Mikael

    2005-01-01

    In energy modulated electron therapy a large fraction of the segments will be arranged as abutting segments where inhomogeneities in segment matching regions must be kept as small as possible. Furthermore, the output variation between different segments should be minimized and must in all cases be well predicted. For electron therapy with add-on collimators, both the electron MLC (eMLC) and the photon MLC (xMLC) contribute to these effects when an xMLC tracking technique is utilized to reduce the x-ray induced leakage. Two add-on electron collimator geometries have been analyzed using Monte Carlo simulations: One isocentric eMLC geometry with an isocentric clearance of 35 cm and air or helium in the treatment head, and one conventional proximity geometry with a clearance of 5 cm and air in the treatment head. The electron fluence output for 22.5 MeV electrons is not significantly affected by the xMLC if the shielding margins are larger than 2-3 cm. For small field sizes and 9.6 MeV electrons, the isocentric design with helium in the treatment head or shielding margins larger than 3 cm is needed to avoid a reduced electron output. Dose inhomogeneity in the matching region of electron segments is, in general, small when collimator positions are adjusted to account for divergence in the field. The effect of xMLC tracking on the electron output can be made negligible while still obtaining a substantially reduced x-ray leakage contribution. Collimator scattering effects do not interfere significantly when abutting beam techniques are properly applied

  8. Multi-year programming of energy - The energy transition for a green growth

    International Nuclear Information System (INIS)

    2016-01-01

    This document gathers several documents. It contains the decree related to the definition of the multi-year programming of energy (in France), and then a synthesis of this policy which addresses its main objectives: to define a coherent framework for action for energy transition, to improve energy efficiency and reduce the consumption of fossil energies, to accelerate the development of renewable energies, to maintain a high level of security of supply while complying with environmental requirements, to prepare tomorrow's energy system, to develop a clean mobility, and to take economic and social of energy transition into account and to act with territories. The next documents address the implementation framework of the multi-year programming of energy, aspects related to energy demand management, aspects related to energy supply, aspects related to security of supply, to the development of infrastructures and to the flexibility of the electricity system, the strategy for the development of a clean mobility, aspects related to social and economic impacts, aspects related to the French western isles. A report is also proposed as an environmental strategic assessment of this programming and of its part related to the strategy for the development of a clean mobility. The opinion of Environmental Authority on this programming is also provided, as well as an information note published as an answer to this opinion. A debate of the national council for energy transition is included, as well as the opinion of the High Council for Energy, the texts of several amendments notably proposed by EDF, and the opinion of the expert committee for energy transition

  9. Positron annihilation induced Auger electron spectroscopy and its implementation at accelerator based low energy positron factories

    International Nuclear Information System (INIS)

    Weiss, A.; Koeymen, A.R.; Mehl, D.; Lee, K.H.; Yang Gimo; Jensen, K.

    1991-01-01

    Positron annihilation induced auger electron spectroscopy (PAES) makes use of a beam of low energy positrons to excite Auger transitions by annihilating core electrons. The large secondary electron background usually present in Auger spectra can be eliminated by setting the positron beam energy well below the Auger electron energy. This allows true Auger lineshapes to be obtained. Further, because the positron is localized just outside the surface before it annihilates, PAES is extremely sensitive to the topmost atomic layer. Recent PAES results obtained at the University of Texas at Arlington will be presented. In addition, the use of high resolution energy analyzers with multichannel particle detection schemes to prevent problems due to the high data rates associated with accelerator based positron beams will be discussed. (orig.)

  10. The energy distribution of electrons in radio jets

    Science.gov (United States)

    Tsouros, Alexandros; Kylafis, Nikolaos D.

    2017-07-01

    Context. Black-hole and neutron-star X-ray binaries exhibit compact radio jets, when they are in the so called quiescent, hard, or hard intermediate states. The radio spectrum in these states is flat to slightly inverted, I.e., the spectral index of the observed flux density is in the range 0 ≲ α ≲ 0.5. It is widely accepted that the energy distribution of the electrons, in the rest frame of the jet, is a power law with index in the range 3 ≲ p ≲ 5. Aims: Contrary to what our thinking was decades ago, now we know that the jets originate in the hot, inner flow around black holes and neutron stars. So it is worth investigating the radio spectrum that is emitted by a thermal jet as a function of direction. Methods: As an example, we consider a parabolic jet and, with the assumption of flux freezing, we compute the emitted spectrum in all directions, from radio to near infrared, using either a thermal distribution of electrons or a power-law one. Results: We have found that parabolic jets with a thermal distribution of electrons give also flat to slightly inverted spectra. In particular, for directions along the jet (θ = 0), both distributions of electron energies give α = 0 ± 0.01. The index α increases as the viewing angle θ increases and for directions perpendicular to the jet (θ = π/ 2), the thermal distribution gives α = 0.40 ± 0.05, while the power-law distribution gives α = 0.20 ± 0.05. The break frequency νb, which marks the transition from partially optically thick to optically thin synchrotron emission, is comparable for the power-law and the thermal distributions. Conclusions: Contrary to common belief, it is not necessary to invoke a power-law energy distribution of the electrons in a jet to explain its flat to slightly inverted radio spectrum. A relativistic Maxwellian produces similar radio spectra. Thus, the jet may be the widely invoked "corona" around black holes in X-ray binaries.

  11. Electronic energy states of HfSe/sub 2/ and NbSe/sub 2/ by low energy electron loss spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Ito, T; Iwami, M; Hiraki, A [Osaka Univ., Suita (Japan). Faculty of Engineering

    1981-06-01

    Low energy electron loss spectroscopy (ELS) study was performed on 1T-HfSe/sub 2/ (group IVB metal compound) and 2H-NbSe/sub 2/ (group VB metal compound) by using incident electron energies of 30-250 eV. From the loss data in the second derivative form, maxima in density-of-states in the conduction band of the compounds were deduced through the information on the filled core states by X-ray photoelectron spectroscopy. The conduction band of the transition-metal dichalcogenides could be divided into two parts. The results are discussed in relation to the previous work on WS/sub 2/ (group VIB metal compound), and also to proposals based on band calculations and experimental studies on the transition-metal dichalcogenides with constituent metals of group IVB, VB and VIB.

  12. Transition from the adiabatic to the sudden limit in core-electron photoemission

    Science.gov (United States)

    Hedin, Lars; Michiels, John; Inglesfield, John

    1998-12-01

    Experimental results for core-electron photoemission Jk(ω) are often compared with the one-electron spectral function Ac(ɛk-ω), where ω is the photon energy, ɛk is the photoelectron energy, and the optical transition matrix elements are taken as constant. Since Jk(ω) is nonzero only for ɛk>0, we must actually compare it with Ac(ɛk-ω)θ(ɛk). For metals Ac(ω) is known to have a quasiparticle (QP) peak with an asymmetric power-law [theories of Mahan, Nozières, de Dominicis, Langreth, and others (MND)] singularity due to low-energy particle-hole excitations. The QP peak starts at the core-electron energy ɛc, and is followed by an extended satellite (shakeup) structure at smaller ω. For photon energies ω just above threshold, ωth=-ɛc, Ac(ɛk-ω)θ(ɛk) as a function of ɛk (ω constant) is cut just behind the quasiparticle peak, and neither the tail of the MND line nor the plasmon satellites are present. The sudden (high-energy) limit is given by a convolution of Ac(ω) and a loss function, i.e., by the Berglund-Spicer two-step expression. Thus Ac(ω) alone does not give the correct photoelectron spectrum, neither at low nor at high energies. We present an extension of the quantum-mechanical (QM) models developed earlier by Inglesfield, and by Bardyszewski and Hedin to calculate Jk(ω). It includes recoil and damping, as well as shakeup effects and extrinsic losses, is exact in the high-energy limit, and allows calculations of Jk(ω) including the MND line and multiple plasmon losses. The model, which involves electrons coupled to quasibosons, is motivated by detailed arguments. As an illustration we have made quantitative calculations for a semi-infinite jellium with the density of aluminum metal and an embedded atom. The coupling functions (fluctuation potentials) between the electron and the quasibosons are related to the random-phase-approximation dielectric function, and different levels of approximations are evaluated numerically. The differences

  13. Electronic energy distribution function at high electron swarm energies in neon

    International Nuclear Information System (INIS)

    Brown, K.L.; Fletcher, J.

    1995-01-01

    Electron swarms moving through a gas under the influence of an applied electric field have been extensively investigated. Swarms at high energies, as measured by the ratio of the applied field to the gas number density, E/N, which are predominant in many applications have, in general, been neglected. Discharges at E/N in the range 300 0 < 133 Pa using a differentially pumped vacuum system in which the swarm electrons are extracted from the discharge and energy analysed in both a parallel plate retarded potential analyser and a cylindrical electrostatic analyser. Both pre-breakdown and post-breakdown discharges have been studied. Initial results indicate that as the discharge traverses breakdown no sudden change in the nature of the discharge occurs and that the discharge can be described by both a Monte Carlo simulation and by a Boltzmann treatment given by Phelps et al. (1987). 18 refs., 8 figs

  14. Municipalities and energy efficiency in countries in transition

    International Nuclear Information System (INIS)

    Rezessy, Silvia; Dimitrov, Konstantin; Urge-Vorsatz, Diana; Baruch, Seth

    2006-01-01

    It is widely recognized that many cost-efficient opportunities to employ end-use energy efficiency measures exist in countries in transition (CITs) and that municipal authorities have an essential role to play in capturing these opportunities. The aim of this paper is to review the factors that determine the degree of involvement of local authorities in the market for energy services and energy efficient (EE) equipment in three CITs: Bulgaria, Hungary and the Former Yugoslav Republic of Macedonia (hereafter: Macedonia). We achieve this aim by examining the current status of local governments as the most powerful determinant of municipal market involvement. Two broad groups of factors are discussed: statutory obligations and powers of local governments, especially energy-related tasks, and finance. We explain how specific features within these two areas may influence the motivation of local authorities to improve energy efficiency and their capacity to do so. We argue that greater decentralization is the first step in augmenting the role of local authorities in the market for energy services and EE equipment. Based on the analysis we give recommendations on how to encourage municipal authorities to use market mechanisms more extensively to deliver energy efficiency

  15. The German energy transition: the end of ambitions?

    International Nuclear Information System (INIS)

    Beeker, Etienne

    2017-08-01

    This article proposes an overview of the German situation regarding the implementation of its energy transition policy (Energiewende) which mainly comprised phasing out nuclear and fossil energies, and their replacement by renewable energies. The authors notably comment figures and tables which illustrate the evolution of greenhouse gas emissions in Germany, France and Europe, the evolution of wind and photovoltaic installations in Germany, the status of the energy mix and the shares of renewable energies in primary consumption in Germany and in France, the electricity productions from the different sources in Germany and in France, the structure of electric power tariffs in Germany and in France. Focusing on the German case, they outline that the objectives defined for 2020 for renewable energies are almost reached, but what comes next remains uncertain. They also notice that the objective of phasing out nuclear in 2022 is kept. They discuss the various difficulties faced by the Energiewende: a too slow improvement of energy efficiency, a development of electric vehicles facing realities of the automotive industry, a difficult but necessary phasing out coal. They outline two main challenges: to face some resistance by the population: the risk of black-outs due to the difficult management of renewable intermittency, and a high level of expenses which are mainly paid by small consumers. The future of this policy may also been put into question again after the elections of September 2017

  16. c -Axis Dimer and Its Electronic Breakup: The Insulator-to-Metal Transition in Ti2 O3

    Science.gov (United States)

    Chang, C. F.; Koethe, T. C.; Hu, Z.; Weinen, J.; Agrestini, S.; Zhao, L.; Gegner, J.; Ott, H.; Panaccione, G.; Wu, Hua; Haverkort, M. W.; Roth, H.; Komarek, A. C.; Offi, F.; Monaco, G.; Liao, Y.-F.; Tsuei, K.-D.; Lin, H.-J.; Chen, C. T.; Tanaka, A.; Tjeng, L. H.

    2018-04-01

    We report on our investigation of the electronic structure of Ti2 O3 using (hard) x-ray photoelectron and soft x-ray absorption spectroscopy. From the distinct satellite structures in the spectra, we have been able to establish unambiguously that the Ti-Ti c -axis dimer in the corundum crystal structure is electronically present and forms an a1 ga1 g molecular singlet in the low-temperature insulating phase. Upon heating, we observe a considerable spectral weight transfer to lower energies with orbital reconstruction. The insulator-metal transition may be viewed as a transition from a solid of isolated Ti-Ti molecules into a solid of electronically partially broken dimers, where the Ti ions acquire additional hopping in the a -b plane via the egπ channel, the opening of which requires consideration of the multiplet structure of the on-site Coulomb interaction.

  17. Atomic transition energies and the variation of the fine-structure constant α

    International Nuclear Information System (INIS)

    Borschevsky, Anastasia; Eliav, Ephraim; Ishikawa, Yasuyuki; Kaldor, Uzi

    2006-01-01

    Relativistic energy shifts of atomic excitation energies, showing the dependence of these energies on the value of the fine-structure constant α, are needed to extract past changes in α from spectra of distant quasars. These shifts are calculated by the Fock-space coupled cluster method and its extrapolated intermediate Hamiltonian extension, which allow high-accuracy treatment of electron correlation. The accuracy of the method is tested by comparing 33 transition energies in heavy atoms (obtained with the laboratory α) with experiment; the average error is 258 cm -1 , and the largest error is 711 cm -1 . This may be compared with an average error of 432 cm -1 and a maximum error of 2150 cm -1 in the work of Dzuba et al., who reported most of the available energy shift calculations. The enhanced accuracy is due to more extensive inclusion of electron correlation. To obtain the energy shifts, we repeated the calculations with different values of α (within 0.1% of the current value). Our shifts differ by up to 30% from the values given by Dzuba et al., with an average difference of 9%. Based on the better quality of the present-day excitation energies, we believe the energy shifts reported here are more accurate than earlier work

  18. Overcoming energy injustice? Bulgaria’s renewable energy transition in times of crisis

    OpenAIRE

    Andreas, Jan-Justus; Burns, Charlotte Jennie; Touza-Montero, Julia Maria

    2018-01-01

    The effects of renewable energy transitions on energy costs and economic growth have led to cost concerns and a prioritisation of economic issues during the economic crisis. Bulgaria, the EU's poorest state has nevertheless already achieved its 2020 renewable energy targets. This achievement seems to challenge the widely held as- sumption that poorer countries struggle to meet environmental objectives. This paper analyses the drivers and implications of Bulgaria's renewables expansion in orde...

  19. Electronic configurations and energies in some thermodynamically correlated laves compounds

    International Nuclear Information System (INIS)

    Campbell, G.M.

    1979-04-01

    The known electronic configurations of simple elements in Laves compounds are correlated with those of the more complex systems to determine their electronic configurations and gaseous state promotion energies

  20. Is there room for hydrogen in energy transition?

    International Nuclear Information System (INIS)

    Beeker, Etienne

    2014-08-01

    As Germany decided to use hydrogen to store huge quantities of renewable energies, this report aims at assessing the opportunities associated with hydrogen in the context of energy transition. The author addresses the various techniques and technologies of hydrogen production, and proposes a prospective economic analysis of these processes: steam reforming, alkaline electrolysis, polymer electrolyte membrane (PEM) electrolysis, and other processes still at R and D level. He gives an overview of existing and potential uses of hydrogen in industry, in energy storage (power-to-gas, power-to-power, methanation) and in mobility (hydrogen-mobility could be a response to hydrocarbon shortage, but the cost is still very high, and issues like hydrogen distribution must be addressed), and also evokes their emergence potential

  1. Role of Sn impurity on electronic topological transitions in 122 Fe-based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Haranath, E-mail: hng@rrcat.gov.in [Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094 (India); Indus Synchrotrons Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Sen, Smritijit [Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094 (India); Indus Synchrotrons Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)

    2016-08-25

    We show that only a few percentage of Sn doping at the Ba site on BaFe{sub 2}As{sub 2}, can cause electronic topological transition, namely, the Lifshitz transition. A hole like d{sub xy} band of Fe undergoes electron like transition due to 4% Sn doping. Lifshitz transition is found in BaFe{sub 2}As{sub 2} system around all the high symmetry points. Our detailed first principles simulation predicts absence of any Lifshitz transition in other 122 family compounds like SrFe{sub 2}As{sub 2}, CaFe{sub 2}As{sub 2} in agreement with experimental observations. This work bears practical significance due to the facts that a few percentage of Sn impurity is in-built in tin-flux grown single crystals method of synthesizing 122 materials and inter-relationship among the Lifshitz transition, magnetism and superconductivity. - Highlights: • Electronic topological transition due to Sn contamination in BaFe{sub 2}As{sub 2}. • Hole like Fe-d{sub xy} band converts into electron like in 3% Sn contaminated BaFe{sub 2}As{sub 2}. • Electron like Fe-d{sub xz}, d{sub yz} bands moves above Fermi Level at X,Y points. • No Lifshitz transition found in Sn-contaminated Sr-122, Ca-122 systems.

  2. Managing transition towards energy efficient housing at the local level

    DEFF Research Database (Denmark)

    Quitzau, Maj-Britt; Hoffmann, Birgitte; Elle, Morten

    2010-01-01

    regulation in several European countries, the general picture remains that existing regimes in the building sector are withheld and that little innovation in terms of new radical energy efficient solutions is taking place. In order to dissolve such a deadlock in the building sector, there is a need to target...... the capability to coordinate and facilitate this complex transition process. The local scale of policy-formulation has been chosen in this paper in order to describe transition processes from the perspective of practitioners, who are hands on the specific building projects. The local scale provides an in......-depth study of how specific practitioners, such as local planning authorities, building firms, building developers, technical experts and suppliers, interact and coordinate their efforts in the local arena of a specific building project (within a more general framework). The focus on the local scale allows...

  3. Electron impact excitation of the n = 2 to n = 3 transition in atomic hydrogen near threshold

    Science.gov (United States)

    Hata, J.; Morgan, L. A.; McDowell, M. R. C.

    1980-06-01

    Close-coupling calculations of electron impact excitation of the n = 2 to n = 3 transition of atomic hydrogen at energies below the n = 4 threshold are presented. The algebraic variational close-coupling code of Morgan (1980) with an eighteen-state basis was used to obtain cross sections at eight impact energies from 2.04 to 2.45 eV, and calculations in a six-state close-coupling model were compared with the six-state calculations of Burke et al. (1967). The six-state values are found to be in satisfactory agreement with the exception of the singlet contribution to the 2s-3s transition. Near the n = 3 threshold the cross section obtained in the full calculation is found to be almost a factor of 2 lower than that predicted by Johnson (1972), thus explaining in part the discrepancy between Johnson's results and experiments on hydrogen plasmas. Estimates of rate coefficients based on the cross sections and assuming a Maxwellian velocity distribution, however, are shown to remain in disagreement with experiment.

  4. Kα satellite transitions in elements with 12≤Z≤30 produced by electron incidence

    International Nuclear Information System (INIS)

    Limandri, Silvina P.; Carreras, Alejo C.; Trincavelli, Jorge C.; Bonetto, Rita D.

    2010-01-01

    The emission of x-ray satellite lines in the Kα region of Mg, Si, Sc, Ti, Cr, Fe, Ni, and Zn induced by electron incidence was studied by means of wavelength dispersive spectroscopy. The satellite lines studied were Kα ' , Kα 3 , Kα 4 , Kα 5 , Kα 6 , and two transitions denoted here as Kα 22 and Kα 12 . Energy shifts with respect to the main Kα 1 diagram line and transition probabilities relative to the whole Kα group were determined for a number of lines through a careful spectral processing. The dependence of these parameters, as well as of the Kβ:Kα intensity ratio, on the atomic number was compared with previous experimental and theoretical determinations when available. A discussion about the different mechanisms responsible for vacancy creation involved in the production of double-ionization satellites was performed in the light of the results obtained. Finally, the behavior of the satellite intensities as a function of the incidence energy was discussed for silicon.

  5. Finland: a model of energy transition to be followed?

    International Nuclear Information System (INIS)

    Lorot, Pascal

    2014-09-01

    Published before the debate of the French Parliament on the law on energy transition, i.e. on a new energy model, or on the construction of a low carbon and less energy consuming society to comply with France's international commitments, this report first discusses the French situation, the evolution of its energy policy, the challenge of a search for a balance between a cheap electricity and energy independence, and the plurality of factors and objectives (economic, budgetary, environmental, industrial, societal, political and social) which are sometime contradictory. The second part presents and comments the case of Germany which seems to be a good example regarding energy policy, however it faces some difficulties and pitfalls: a quick evolution of the energy mix in favour of renewable energies, but an always higher cost supported almost only by individuals, a disturbed electricity market, an environmental impact due to the wider use of coal (less expensive than gas). The third part addresses the case of Finland which could be a more inspiring example: no decision to phase out nuclear, no decision of a quick and forced development of renewable energies, modification of the energy mix by the development of local forest resources, an electric system of good quality, a high energetic competitiveness. The report outlines the consistency of the Finnish policy: search for a balance between international commitments of reduction of greenhouse gas emissions, competitive tariffs, and strengthening of energetic independence. The associated choices are discussed, and it appears that the cost-efficiency criterion is prevailing

  6. Formation of a superhigh energy electron spectrum in the Galaxy

    International Nuclear Information System (INIS)

    Agaronyan, F.A.; Ambartsumyan, A.S.

    1985-01-01

    The formation of superhigh energy electron spectrum in the disk of the galaxy and halo is considered. A different behaviour of the electron spectrum within the framework of capture models in disk or halo, in the energy region E> or approximately 10 5 GeV is revealed due to the account of relativistic corrections ir the energy losses of electrons during the inverse Compton scattering. A comparison with the existing experimental data is carried out

  7. Energy levels and radiative rates for transitions in Ti VI

    International Nuclear Information System (INIS)

    Aggarwal, K M; Keenan, F P; Msezane, A Z

    2013-01-01

    We report on calculations of energy levels, radiative rates, oscillator strengths and line strengths for transitions among the lowest 253 levels of the (1s 2 2s 2 2p 6 ) 3s 2 3p 5 , 3s3p 6 , 3s 2 3p 4 3d, 3s3p 5 3d, 3s 2 3p 3 3d 2 , 3s 2 3p 4 4s, 3s 2 3p 4 4p and 3s 2 3p 4 4d configurations of Ti VI. The general-purpose relativistic atomic structure package and flexible atomic code are adopted for the calculations. Radiative rates, oscillator strengths and line strengths are reported for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2) and magnetic quadrupole (M2) transitions among the 253 levels, although calculations have been performed for a much larger number of levels. Comparisons are made with existing available results and the accuracy of the data is assessed. Additionally, lifetimes for all 253 levels are listed, although comparisons with other theoretical results are limited to only 88 levels. Our energy levels are estimated to be accurate to better than 1% (within 0.03 Ryd), whereas results for other parameters are probably accurate to better than 20%. A reassessment of the energy level data on the National Institute of Standards and Technology website for Ti VI is suggested. (paper)

  8. Efficient spin transitions in inelastic electron tunneling spectroscopy.

    Science.gov (United States)

    Lorente, Nicolás; Gauyacq, Jean-Pierre

    2009-10-23

    The excitation of the spin degrees of freedom of an adsorbed atom by tunneling electrons is computed using strong coupling theory. Recent measurements [Heinrich, Science 306, 466 (2004)] reveal that electron currents in a magnetic system efficiently excite its magnetic moments. Our theory shows that the incoming electron spin strongly couples with that of the adsorbate so that memory of the initial spin state is lost, leading to large excitation efficiencies. First-principles transmissions are evaluated in quantitative agreement with the experiment.

  9. Electron polarimetry at low energies in Hall C at JLab

    International Nuclear Information System (INIS)

    Gaskell, D.

    2013-01-01

    Although the majority of Jefferson Lab experiments require multi-GeV electron beams, there have been a few opportunities to make electron beam polarization measurements at rather low energies. This proceedings will discuss some of the practical difficulties encountered in performing electron polarimetry via Mo/ller scattering at energies on the order of a few hundred MeV. Prospects for Compton polarimetry at very low energies will also be discussed. While Mo/ller scattering is likely the preferred method for electron polarimetry at energies below 500 MeV, there are certain aspects of the polarimeter and experiment design that must be carefully considered

  10. Study of the low energy gamma transitions of molybdenum 99; Etude des transitions gamma de basse energie du molybdene 99

    Energy Technology Data Exchange (ETDEWEB)

    Ravier, J.

    1959-07-01

    The study of the decay scheme of Mo{sup 99} has been performed on the magnetic iron-less and double focalization spectrograph of the Institute of Nuclear Physics of Lyon. Methods of internal and external conversion have been used. The intensities of the Mo{sup 99} sources used were not strong enough to determine the characteristics of the internal conversion accurately but were sufficient to precise the decay scheme at low energy. We have determined the internal conversion ratio for the transition of 180 KeV, we have got: 0.13 ± 0.03 which is not in agreement with the value given by a previous experiment based on γ-γ coincidence. Our method seems to be more reliable. We confirm the E2 feature of this transition and its 5/2+ spin. We have determined another important parameter for the 180 KeV de-excitation: the percentage of transitions that do not pass by the isomeric level but by the 140 KeV level is (6 ± 2)%, the isomeric level being at 142 KeV. The gamma spectra at low energy has been studied through the photoelectric effect in a lead converter [French] L'etude du schema de desintegration du Mo{sup 99} deja faite par differents auteurs a ete reprise par des methodes de conversion interne et externe, an moyen du spectrographe magnetique sans fer et a double focalisation de l'Institut de Physique Nucleaire de Lyon. Apres avoir cherche les possibilites d'obtention de sources de haute activite specifique par separation isotopique Szilard-Chalmers sur des molybdates alcalins, le spectre de conversion interne a basse energie a ete mesure. Ainsi se trouverent etre determines les coefficients partiaux de conversion interne. Le spectre γ a basse energie a ete etudier au moyen de l'effet photoelectrique sur un convertisseur de plomb. Les coefficients de conversion interne et les intensites relatives des differentes transitions ont ete calcules moyennant certaines hypotheses. La comparaison entre les valeurs donnees par la theorie et l'experience des differentes

  11. Optical transitions involving unconfined energy states in In/sub x/Ga/sub 1-//sub x/As/GaAs multiple quantum wells

    International Nuclear Information System (INIS)

    Ji, G.; Dobbelaere, W.; Huang, D.; Morkoc, H.

    1989-01-01

    Optical transitions with energies higher than that of the GaAs band gap in highly strained In/sub x/Ga/sub 1-//sub x/As/GaAs multiple--quantum-well structures have been observed in photoreflectance spectra. In some samples as many as seven such structures were present. We identify them as transitions between the unconfined electron states and the confined heavy-hole states. For energies below the GaAs signal, intense transitions corresponding to such unconfined electron subbands were also observed. The intensity of the transitions involving unconfined electron subbands decreases with increasing well width, but is weakly dependent on the mole fraction x. The transmission coefficients are calculated in order to locate the positions of the unconfined electron subband energies. Good agreement is obtained between the experimental data and the theoretical calculation

  12. Tantalum surface oxidation: Bond relaxation, energy entrapment, and electron polarization

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yongling [Key Laboratory of Low-Dimensional Materials and Application Technologies (Ministry of Education), Hunan Provincial Key Laboratory of Thin Film Materials and Devices, Faculty of Materials Science and Engineering, Xiangtan University, Hunan 411105 (China); Bo, Maolin [Yangtze Normal University, College of Mechanical and Electrical Engineering, Chongqing 408100 (China); Wang, Yan [School of Information and Electronic Engineering, Hunan University of Science and Technology, Hunan 411201 (China); Liu, Yonghui [Key Laboratory of Low-Dimensional Materials and Application Technologies (Ministry of Education), Hunan Provincial Key Laboratory of Thin Film Materials and Devices, Faculty of Materials Science and Engineering, Xiangtan University, Hunan 411105 (China); Sun, Chang Q. [NOVITAS, School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Huang, Yongli, E-mail: huangyongli@xtu.edu.cn [Key Laboratory of Low-Dimensional Materials and Application Technologies (Ministry of Education), Hunan Provincial Key Laboratory of Thin Film Materials and Devices, Faculty of Materials Science and Engineering, Xiangtan University, Hunan 411105 (China)

    2017-02-28

    Graphical abstract: The bond, electron and energy relaxation result in core level energy shift, local densification, quantum entrapment and electron polarization of bonding electrons. - Highlights: • Increasing the oxygen coverage lowers the adsorption energy associated with lattice reconstruction. • Electrons transfer from Ta surface atoms to sp-hydrated oxygen, creating dipole moment that decreases the work function. • Oxygen chemisorption modified valence density-of-state (DOS) for Ta with four excessive DOS features: O−Ta bonding, O{sup 2−} lone pairs, Ta+ electron holes, and the lone-pair polarized Ta dipoles. • The bond, electron and energy relaxation between surface undercoordinated atoms are responsible for core level energy shift, local densification, quantum entrapment and electron polarization of bonding electrons. - Abstract: A combination of photoelectron spectrometric analysis and density functional theory calculations has enabled reconciliation of the bond-energy-electron relaxation for the Ta(100, 110, 111) surfaces chemisorbed with oxygen at different coverages. Results show that increasing oxygen coverage lowers the adsorption energy associated with lattice reconstruction. Valence electrons transfer from Ta surface atoms to oxygen to create four excessive DOS features in terms of O−Ta bonding, lone pairs of oxygen, Ta{sup +} electron holes, and polarized Ta dipoles. Oxidation proceeds in the following dynamics: oxygen gets electrons from two neighboring Ta atoms left behind Ta{sup +}; the sp{sup 3}-orbital hybridization takes place with additional two electron lone pairs, the lone pairs polarize the other two Ta neighbors becoming dipoles. X-ray photoelectron spectral analysis results in the 4f binding energy of an isolated Ta atom and its shift upon bond formation and oxidation. Exercises provide not only a promising numerical approach for the quantitative information about the bond and electronic behavior but also consistent

  13. Tantalum surface oxidation: Bond relaxation, energy entrapment, and electron polarization

    International Nuclear Information System (INIS)

    Guo, Yongling; Bo, Maolin; Wang, Yan; Liu, Yonghui; Sun, Chang Q.; Huang, Yongli

    2017-01-01

    Graphical abstract: The bond, electron and energy relaxation result in core level energy shift, local densification, quantum entrapment and electron polarization of bonding electrons. - Highlights: • Increasing the oxygen coverage lowers the adsorption energy associated with lattice reconstruction. • Electrons transfer from Ta surface atoms to sp-hydrated oxygen, creating dipole moment that decreases the work function. • Oxygen chemisorption modified valence density-of-state (DOS) for Ta with four excessive DOS features: O−Ta bonding, O"2"− lone pairs, Ta+ electron holes, and the lone-pair polarized Ta dipoles. • The bond, electron and energy relaxation between surface undercoordinated atoms are responsible for core level energy shift, local densification, quantum entrapment and electron polarization of bonding electrons. - Abstract: A combination of photoelectron spectrometric analysis and density functional theory calculations has enabled reconciliation of the bond-energy-electron relaxation for the Ta(100, 110, 111) surfaces chemisorbed with oxygen at different coverages. Results show that increasing oxygen coverage lowers the adsorption energy associated with lattice reconstruction. Valence electrons transfer from Ta surface atoms to oxygen to create four excessive DOS features in terms of O−Ta bonding, lone pairs of oxygen, Ta"+ electron holes, and polarized Ta dipoles. Oxidation proceeds in the following dynamics: oxygen gets electrons from two neighboring Ta atoms left behind Ta"+; the sp"3-orbital hybridization takes place with additional two electron lone pairs, the lone pairs polarize the other two Ta neighbors becoming dipoles. X-ray photoelectron spectral analysis results in the 4f binding energy of an isolated Ta atom and its shift upon bond formation and oxidation. Exercises provide not only a promising numerical approach for the quantitative information about the bond and electronic behavior but also consistent insight into the

  14. The electronic conduction of glass and glass ceramics containing various transition metal oxides

    International Nuclear Information System (INIS)

    Yoshida, T.; Matsuno, Y.

    1980-01-01

    Nb 2 O 5 -V 2 O 5 -P 2 O 5 glasses containing only Group Va oxides have been investigated to elucidate their electronic conduction and structure, as compared with other glasses obtained by the addition of various transition metal oxides to vanadium phosphate. The P 2 O 5 introduction for Nb 2 O 5 in this glass with the same amount of V 2 O 5 increased the conductivity about two times. Glass ceramics having high conductivity increased by two orders of magnitude and the activation energy for conduction decreased from about 0.5 to 0.2 eV. The crystals were confirmed to be (V,Nb) 2 O 5 and Nb phosphate, one of which was highly conductive and developed a pillar-like shape with a length of more than 20 μm. (orig.)

  15. Electronic Structure of the Pyrochlore-Type Ru Oxides through the Metal--Insulator Transition

    International Nuclear Information System (INIS)

    Okamoto, J.; Fujimori, S.I.; Okane, T.; Fujimori, A.; Abbate, M.; Yoshii, S.; Sato, M.

    2003-01-01

    The electronic structures of the pyrochlore-type Ru oxides Sm 2-x Ca x Ru 2 O 7 and Sm 2-x Bi x Ru 2 O 7 , which show metal-insulator transition with increasing Ca or Bi concentration, have been studied by ultraviolet photoemission spectroscopy. Spectral changes near the Fermi level are different but reflect the tendency of their transport properties in both systems. The Sm 2-x Ca x Ru 2 O 7 system shows an energy shift, which is expected from the increase of hole in the Ru 4d t 2g band and the Sm 2 - x Bi x Ru 2 O 7 system shows spectral weight transfer within the Ru 4d t 2g band, which is expected to be observed in bandwidth-control Mott-Hubbard system. (author)

  16. On the gyro resonance electron-whistler interaction in transition layers of near-earth plasma

    International Nuclear Information System (INIS)

    Erokhin, N.S.; Zol'nikova, N.N.; Mikhajlovskaya, L.A.

    1996-01-01

    Gyro resonance interaction of electrons with low amplitude triggered whistler in the transition layers of the ionospheric and magnetospheric plasma that correspond to the blurred jumps of the magnetic field and plasma concentration was studied

  17. Harvesting energy: Place and local entrepreneurship in community-based renewable energy transition

    International Nuclear Information System (INIS)

    Süsser, Diana; Döring, Martin; Ratter, Beate M.W.

    2017-01-01

    Transition towards a renewable energy supply initiates a physical (re)shaping of places and a social transformation of communities into renewable energy communities. Although socio-cultural challenges of energy transition have been recognised (), understandings about socio-geographic places of energy transition and their underlying social processes and structures are insufficiently studied and often remain underestimated. To close this gap, we theoretically and empirically analysed the multifaceted interplay between place, local entrepreneurship and ‘community renewable energy’. Our study is based on an analysis of regional documents and policy reports, and on qualitative interviews undertaken with inhabitants in the case-study municipality of Reußenköge (Germany). Our findings reveal two important aspects: Firstly, people's individual and shared place meanings which materialised in social, physical, historical and climate-related place-attachments and meanings of contested and innovative place are important ingredients bearing an impact on processes of adopting or rejecting renewables. Secondly, differentiated characteristics of entrepreneurs, namely grounded, collaborative, innovative, change-making, economic, communicating, networking and political aspects, appeared to be relevant for the acceptance and support in community-based renewable energy projects. Our findings reveal that energy policies, funding schemes and administrative structures should recognise local socio-geographic important elements in the context of a sustained and decentralised energy transition. - Highlights: • Places are resources of experiences, creativity and innovation for community renewables. • Energy policies should recognise place-based approaches to grassroots community energy actions. • A located view of multifaceted entrepreneurship is relevant to support community renewable energy. • Supportive funding schemes should empower community-based concepts.

  18. Towards the sustainable energy system. The future of the transition policy for energy and environment

    International Nuclear Information System (INIS)

    Bruggink, J.J.C.

    2006-11-01

    Inaugural speech at the occasion of the acceptance of the office for Energy Transition and Sustainable Development at the Faculty of Earth and Life Sciences of the Vrije Universiteit in Amsterdam, Netherlands, November 21, 2006. The transition policy in the Netherlands towards a sustainable energy supply system succeeded in creating a basis in the Dutch society, although at the cost of making clear choices with regard to concrete projects, new policy tools and financial means. In order to accelerate those choices the Dutch government needs to take decisive measures [nl

  19. Anisotropic electron distribution functions and the transition between the Weibel and the whistler instabilities

    International Nuclear Information System (INIS)

    Pegoraro, F.; Palodhi, L.; Califano, F.

    2013-01-01

    Electron distribution functions that are anisotropic in phase space are a common feature of collisionless plasmas both in space and in the laboratory and the investigation of the processes through which these distributions relax is of primary interest. In fact, the free energy that is made available by the unbalance of the particle “temperatures” in the different directions can be transferred, depending on the plasma conditions, to quasistatic magnetic fields, to electromagnetic or electrostatic coherent structures or to particle acceleration. The anisotropy of the electron distribution function in an unmagnetized plasma can give rise to the onset of the well known Weibel instability which generates a quasistatic magnetic field. If a magnetic field is already present in the plasma, the Weibel instability driven by the anisotropy of the electron energy distribution turns into the so called whistler instability, in which case circularly polarized whistler waves are generated by the relaxation of the electron distribution function. Whistler waves are actually ubiquitous in plasmas and their generation has been extensively studied in recent years in the laboratory. Whistler instabilities have been reported in space where bursts of whistler mode magnetic noise are found to be present in the magnetosphere, close to the magnetopause and are also a likely source of several different magnetospheric fluctuations including plasmaspheric hiss and magnetospheric chorus. In this presentation the transition between non resonant (Weibel-type) and resonant (whistler) instabilities is investigated numerically in plasma configurations with an ambient magnetic field of increasing amplitudes. The Vlasov-Maxwell system is solved in a configuration where the fields have three components but depend only on one coordinate and on time. The nonlinear evolution of these instabilities is shown to lead to the excitation of electromagnetic and electrostatic modes at the first few harmonics

  20. 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.

  1. Low-energy electron transmission and secondary-electron emission experiments on crystalline and molten long-chain alkanes

    International Nuclear Information System (INIS)

    Ueno, N.; Sugita, K.; Seki, K.; Inokuchi, H.

    1986-01-01

    This paper describes the results of low-energy electron transmission and secondary-electron emission experiments on thin films of long-chain alkanes deposited on metal substrates. The spectral changes due to crystal-melt phase transition were measured in situ in both experiments. The ground-state energy V 0 of the quasifree electron in crystalline state was determined to be 0.5 +- 0.1 eV. The value of V 0 for the molten state was found to be negative. Further, in the crystalline state evidence is found for a direct correspondence between the transmission maxima and the high value of the density of states in the conduction bands

  2. Fluorescence excitation involving multiple electron transition states of N{sub 2} and CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Wu, C.Y.R.; Chen, F.Z.; Hung, T.; Judge, D.L. [Univ. of Southern California, Los Angeles, CA (United States)

    1997-04-01

    The electronic states and electronic structures of N{sub 2} and CO{sub 2} in the 8-50 eV energy region have been studied extensively both experimentally and theoretically. In the energy region higher than 25 eV there exists many electronic states including multiple electron transition (MET) states which are responsible for producing most of the dissociative photoionization products. The electronic states at energies higher than 50 eV have been mainly determined by Auger spectroscopy, double charge transfer, photofragment spectroscopy and ion-ion coincidence spectroscopy. The absorption and ionization spectra of these molecules at energies higher than 50 eV mainly show a monotonic decrease in cross section values and exhibit structureless features. The decay channels of MET and Rydberg (or superexcited) states include autoionization, ionization, dissociative ionization, predissociation, and dissociation while those of single ion and multiple ion states may involve predissociation. and dissociation processes. The study of fluorescence specifically probes electronically excited species resulting from the above-mentioned decay channels and provides information for understanding the competition among these channels.

  3. Measurements of 2s-2p transition energies in helium-like and lithium-like nickel

    International Nuclear Information System (INIS)

    Zacarias, A.S.; Livingston, A.E.; Lu, Y.N.; Ward, R.F.; Berry, H.G.; Dunford, R.W.

    1987-01-01

    The wavelength of the fine structure transition 1s2s 3 S 1 - 1s2p 3 P 2 in Ni XXVII has been measured using fast-ion spectroscopy. The transition energy is sensitive to relativistic and Lamb shift corrections in this high-Z two-electron system. Comparison is made with measurements in other high-Z ions and with recent theoretical calculations. A preliminary measurement of the 1s 2 2s 2 S/sub 1/2/ - 1s 2 2p 2 P/sub 1/2/ find structure transition in Ni XXVI is also reported. 18 refs., 1 fig., 2 tabs

  4. Strongly Coupled Magnetic and Electronic Transitions in Multivalent Strontium Cobaltites

    OpenAIRE

    Lee, J. H.; Choi, Woo Seok; Jeen, H.; Lee, H.-J.; Seo, J. H.; Nam, J.; Yeom, M. S.; Lee, H. N.

    2017-01-01

    The topotactic phase transition in SrCoO x (x = 2.5–3.0) makes it possible to reversibly transit between the two distinct phases, i.e. the brownmillerite SrCoO2.5 that is a room-temperature antiferromagnetic insulator (AFM-I) and the perovskite SrCoO3 that is a ferromagnetic metal (FM-M), owing to their multiple valence states. For the intermediate x values, the two distinct phases are expected to strongly compete with each other. With oxidation of SrCoO2.5, however, it has been conjectured t...

  5. Power electronic converter systems for direct drive renewable energy applications

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    This chapter presents power electronic conversion systems for wind and marine energy generation applications, in particular, direct drive generator energy conversion systems. Various topologies are presented and system design optimization and reliability are briefly discussed....

  6. LAT Perspectives in Detection of High Energy Cosmic Ray Electrons

    International Nuclear Information System (INIS)

    Moiseev, Alexander; Ormes, J.F.; Funk, Stefan

    2007-01-01

    The LAT science objectives and capabilities in the detection of high energy electrons in the energy range from 20 GeV to ∼1.5 TeV are presented. LAT simulations are used to establish the event selections. It is found that maintaining the efficiency of electron detection at the level of 30%, the residual hadron contamination does not exceed 2-3% of the electron flux. It is expected to collect ∼ ten million of electrons with the energy above 20 GeV for one year of observation. Precise spectrum reconstruction with collected electron statistics opens the unique opportunity to investigate several important problems such as models of IC radiation, revealing the signatures of nearby sources such as high energy cutoff in the electron spectrum, testing the propagation model, and search for KKDM particles decay through their contribution to the electron spectrum

  7. Intra- and inter-atomic optical transitions of Fe, Co, and Ni ferrocyanides studied using first-principles many-electron calculations

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Shinta, E-mail: s-watanabe@nucl.nagoya-u.ac.jp, E-mail: j-onoe@nucl.nagoya-u.ac.jp; Sawada, Yuki; Nakaya, Masato; Yoshino, Masahito; Nagasaki, Takanori; Onoe, Jun, E-mail: s-watanabe@nucl.nagoya-u.ac.jp, E-mail: j-onoe@nucl.nagoya-u.ac.jp [Department of Materials, Physics and Energy Engineering, Graduated School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Kameyama, Tatsuya; Torimoto, Tsukasa [Department of Crystalline Materials Science, Graduated School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Inaba, Yusuke; Takahashi, Hideharu; Takeshita, Kenji [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1-N1-16 O-okayama, Meguro-ku, Tokyo 152-8550 (Japan)

    2016-06-21

    We have investigated the electronic structures and optical properties of Fe, Co, and Ni ferrocyanide nanoparticles using first-principles relativistic many-electron calculations. The overall features of the theoretical absorption spectra for Fe, Ni, and Co ferrocyanides calculated using a first-principles many-electron method well reproduced the experimental one. The origins of the experimental absorption spectra were clarified by performing a configuration analysis based on the many-electron wave functions. For Fe ferrocyanide, the experimental absorption peaks originated from not only the charge-transfer transitions from Fe{sup 2+} to Fe{sup 3+} but also the 3d-3d intra-transitions of Fe{sup 3+} ions. In addition, the spin crossover transition of Fe{sup 3+} predicted by the many-electron calculations was about 0.24 eV. For Co ferrocyanide, the experimental absorption peaks were mainly attributed to the 3d-3d intra-transitions of Fe{sup 2+} ions. In contrast to the Fe and Co ferrocyanides, Ni ferrocyanide showed that the absorption peaks originated from the 3d-3d intra-transitions of Ni{sup 3+} ions in a low-energy region, while from both the 3d-3d intra-transitions of Fe{sup 2+} ions and the charge-transfer transitions from Fe{sup 2+} to Ni{sup 3+} in a high-energy region. These results were quite different from those of density-functional theory (DFT) calculations. The discrepancy between the results of DFT calculations and those of many-electron calculations suggested that the intra- and inter-atomic transitions of transition metal ions are significantly affected by the many-body effects of strongly correlated 3d electrons.

  8. Quantum spin-glass transition in the two-dimensional electron gas

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 58; Issue 2 ... Spin glasses; quantum phase transition; ferromagnetism; electron gas. ... We argue that a quantum transition involving the destruction of the spin-glass order in an applied in-plane magnetic field offers a natural explanation of some features of recent ...

  9. Effects of electron transitions on the susceptibility of Cd3Mg

    International Nuclear Information System (INIS)

    Sereda, Yu.P.

    1988-01-01

    The monotone susceptibility component has been examined at 4.2-420 K for Cd 1-x Mg x ordering single crystals for 0.18 < x < 0.33. The temperature and concentration curves for the susceptibility components show features related to structural and electronic topological transitions. The susceptibility anomalies at the electron-transition points are correlated with the boundaries to the existence of the allotropic forms

  10. Transition of radial electric field by electron cyclotron heating in stellarator plasmas

    International Nuclear Information System (INIS)

    Idei, H.; Ida, K.; Sanuki, H.

    1993-06-01

    The transition of a radial electric field from a negative to a positive value is observed in Compact Helical System when the electron loss is sufficiently enhanced by the superposition of the off-axis second harmonic electron cyclotron heating on the neutral beam heated plasmas. The observed threshold for the enhanced particle flux required to cause the transition is compared with a theoretical prediction. (author)

  11. Electronic and ionic conductivity studies on microwave synthesized glasses containing transition metal ions

    Directory of Open Access Journals (Sweden)

    Basareddy Sujatha

    2017-01-01

    Full Text Available Glasses in the system xV2O5·20Li2O·(80 − x [0.6B2O3:0.4ZnO] (where 10 ≤ x ≤ 50 have been prepared by a simple microwave method. Microwave synthesis of materials offers advantages of efficient transformation of energy throughout the volume in an effectively short time. Conductivity in these glasses was controlled by the concentration of transition metal ion (TMI. The dc conductivity follows Arrhenius law and the activation energies determined by regression analysis varies with the content of V2O5 in a non-linear passion. This non-linearity is due to different conduction mechanisms operating in the investigated glasses. Impedance and electron paramagnetic resonance (EPR spectroscopic studies were performed to elucidate the nature of conduction mechanism. Cole–cole plots of the investigated glasses consist of (i single semicircle with a low frequency spur, (ii two depressed semicircles and (iii single semicircle without spur, which suggests the operation of two conduction mechanisms. EPR spectra reveal the existence of electronic conduction between aliovalent vanadium sites. Further, in highly modified (10V2O5 mol% glasses Li+ ion migration dominates.

  12. Thermal entanglement between π-electrons in silicene and photons; occurrence of phase transitions

    Energy Technology Data Exchange (ETDEWEB)

    Rastgoo, S., E-mail: rastgooo@gmail.com [Mathematics and Computer Science Department, Sirjan University of Technology, Sirjan 78137 (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)

    2017-03-18

    In this article, the thermal entanglement between π-electronic states in a monolayer silicene sheet and a single mode quantized electromagnetic field is investigated. We assume that the system is in thermal equilibrium with the environment at a temperature T, so that the whole system is described by the Boltzmann distribution. Using the states of total Hamiltonian, the thermal density matrix and, consequently, its partially transposed one is computed, giving rise to the determination of negativity. Our analytical calculations, along with representative figures, show that the system is separable at zero temperature, exhibits a maximum, at a specific temperature, and asymptotically vanishes. Along these lines we also report the effects of electron–photon coupling, as well as the silicene buckling, on the entanglement. Specifically, we demonstrate that the maximal value of entanglement is larger for stronger electron–photon coupling, while it decreases for larger buckling effect. Moreover, we show that the gap in the total energy spectrum remains intact for any value of the buckling parameter. There is, however, one state whose energy changes sign, at a specific buckling, indicating a change of phase. - Highlights: • Thermal entanglement between π-electrons and photons in silicene is reported. • Intrinsic spin-orbit coupling and buckling effect are taken into account. • The ground state of the system is shown to be separable. • Thermal entanglement exhibits a maximum at a certain controllable temperature. • A rapid increase in the negativity for small temperature and buckling indicates a phase transition.

  13. Phase transformation in multiferroic Bi5Ti3FeO15 ceramics by temperature-dependent ellipsometric and Raman spectra: An interband electronic transition evidence

    Science.gov (United States)

    Jiang, P. P.; Duan, Z. H.; Xu, L. P.; Zhang, X. L.; Li, Y. W.; Hu, Z. G.; Chu, J. H.

    2014-02-01

    Thermal evolution and an intermediate phase between ferroelectric orthorhombic and paraelectric tetragonal phase of multiferroic Bi5Ti3FeO15 ceramic have been investigated by temperature-dependent spectroscopic ellipsometry and Raman scattering. Dielectric functions and interband transitions extracted from the standard critical-point model show two dramatic anomalies in the temperature range of 200-873 K. It was found that the anomalous temperature dependence of electronic transition energies and Raman mode frequencies around 800 K can be ascribed to intermediate phase transformation. Moreover, the disappearance of electronic transition around 3 eV at 590 K is associated with the conductive property.

  14. Enhanced energy deposition symmetry by hot electron transport

    International Nuclear Information System (INIS)

    Wilson, D.; Mack, J.; Stover, E.; VanHulsteyn, D.; McCall, G.; Hauer, A.

    1981-01-01

    High energy electrons produced by resonance absorption carry the CO 2 laser energy absorbed in a laser fusion pellet. The symmetrization that can be achieved by lateral transport of the hot electrons as they deposit their energy is discussed. A K/sub α/ experiment shows a surprising symmetrization of energy deposition achieved by adding a thin layer of plastic to a copper sphere. Efforts to numerically model this effect are described

  15. Local energy governance in vermont: an analysis of energy system transition strategies and actor capacity

    Science.gov (United States)

    Rowse, Tarah

    While global, national, and regional efforts to address climate and energy challenges remain essential, local governments and community groups are playing an increasingly stronger and vital role. As an active state in energy system policy, planning and innovation, Vermont offers a testing ground for research into energy governance at the local level. A baseline understanding of the energy planning and energy organizing activities initiated at the local level can support efforts to foster a transition to a sustainable energy system in Vermont. Following an inductive, applied and participatory approach, and grounded in the fields of sustainability transitions, energy planning, and community energy, this research project identifies conditions for change, including opportunities and challenges, within Vermont energy system decision-making and governance at the local level. The following questions are posed: What are the main opportunities and challenges for sustainable energy development at the town level? How are towns approaching energy planning? What are the triggers that will facilitate a faster transition to alternative energy systems, energy efficiency initiatives, and localized approaches? In an effort to answer these questions two studies were conducted: 1) an analysis of municipal energy plans, and 2) a survey of local energy actors. Study 1 examined Vermont energy planning at the state and local level through a review and comparison of 40 municipal plan energy chapters with the state 2011 Comprehensive Energy Plan. On average, municipal plans mentioned just over half of the 24 high-level strategies identified in the Comprehensive Energy Plan. Areas of strong and weak agreement were examined. Increased state and regional interaction with municipal energy planners would support more holistic and coordinated energy planning. The study concludes that while municipalities are keenly aware of the importance of education and partnerships, stronger policy mechanisms

  16. Financing Innovations for the Renewable Energy Transition in Europe

    Directory of Open Access Journals (Sweden)

    Raphael Bointner

    2016-11-01

    Full Text Available Renewable energy sources are vital to achieving Europe’s 2030 energy transition goals. Technological innovation, driven by public expenditures on research and development, is a major driver for this change. Thus, an extensive dataset on these expenditures of the European Member States and the European Commission, dating back to the early 1970s, was created. This paper creates predictive scenarios of public investment in renewable energy research and development in Europe based on this historical dataset and current trends. Funding from both, European Member States and the European Commission, between today and 2030 are used in the analysis. The impact on the cumulative knowledge stock is also estimated. Two projection scenarios are presented: (1 business as usual; and (2 an advanced scenario, based on the assumption that the Mission Innovation initiative causes public expenditures to increase in the coming years. Both scenarios are compared to the European 2030 climate and energy framework target sets. Results indicate that Member States in Europe currently tend to fund renewables more than the European Commission, but funding from both sources is expected to increase in the future. Furthermore, the European Commission distributes its funding more equally across the various renewable energy sources than Member States.

  17. Electron emission from materials at low excitation energies

    International Nuclear Information System (INIS)

    Urma, N.; Kijek, M.; Millar, J.J.

    1996-01-01

    Full text: An experimental system has been designed and developed with the purpose of measuring the total electron emission yield from materials at low energy excitation. In the first instance the reliability of the system was checked by measuring the total electron emission yield for a well defined surface (aluminium 99.45%). The obtained data was in the expected range given by the literature, and consequently the system will be used further for measuring the total electron yield for a range of materials with interest in the instrumentation industry. We intend to measure the total electron emission yield under electron bombardment as a function of incident electron energy up to 1200 eV, angle of incidence, state of the surface and environment to which the surface has been exposed. Dependence of emission on total electron irradiated dose is also of interest. For many practical application of the 'Secondary Electron Emission', the total electron yield is desired to be as large as possible. The above phenomenon has practical applicability in electron multiplier tube and Scanning electron microscopy - when by means of the variation of the yield of the emitted electrons one may produce visible images of small sample areas. The electron multiplier tube, is a device which utilises the above effect to detect and amplify both single particles and low currents streams of charged particles. The majority of electron tubes use electrons with low energy, hundreds of eV. Not a lot has been published in the literature about this regime and also about the emission when the impinging electrons have small energy, up to 1 KeV. The information obtained from the experimental measurements concerning the total electron emission yield is used to asses the investigated materials as a potential electron emitting surfaces or dynodes in an electron multiplier tube

  18. Influence of high energy electrons on ECRH in LHD

    Directory of Open Access Journals (Sweden)

    Ogasawara S.

    2012-09-01

    Full Text Available The central bulk electron temperature of more than 20 keV is achieved in LHD as a result of increasing the injection power and the lowering the electron density near 2 × 1018 m−3. Such collision-less regime is important from the aspect of the neoclassical transport and also the potential structure formation. The presences of appreciable amount of high energy electrons are indicated from hard X-ray PHA, and the discrepancy between the stored energy and kinetic energy estimated from Thomson scattering. ECE spectrum are also sensitive to the presence of high energy electrons and discussed by solving the radiation transfer equation. The ECRH power absorption to the bulk and the high energy electrons are dramatically affected by the acceleration and the confinement of high energy electrons. The heating mechanisms and the acceleration process of high energy electrons are discussed by comparing the experimental results and the ray tracing calculation under assumed various density and mean energy of high energy electrons.

  19. Energy transition in and by the local media

    DEFF Research Database (Denmark)

    Horsbøl, Anders

    2013-01-01

    have addressed the media at a national or international level. This article investigates the mediating of a local, municipal initiative, i.e. the so-called ‘Energy Town Frederikshavn’ project in northern Denmark, which has set the ambitious goal of complete transition to renewable energy consumption...... and CO2 neutrality within a few years. Using frame analysis, informed by discourse studies, the article analyzes how the project emerged and was established as a public phenomenon in the media coverage, including how it was made intelligible and which social actors were represented as having a say...... on the matter. The findings show several differences to national or international representations of climate change and sustainability, such as a prevalent profiling frame and an indication of a reversal of the so-called Giddens’ paradox....

  20. ELEC-2005: Electronics in High Energy Physics

    CERN Multimedia

    Monique Duval

    2004-01-01

    ELEC-2005 is a new course series on modern electronics, given by CERN physicists and engineers in the format of the successful ELEC-2002 course series, and within the framework of the 2005 Technical Training Programme. This comprehensive course series is designed for people who are not electronics specialists, for example physicists, engineers and technicians working at or visiting the laboratory, who use or will use electronics in their present or future activities, in particular in the context of the LHC accelerator and experiments. ELEC-2005 will composed of four Terms throughout the year: Winter Term: Introduction to electronics in HEP (January-February, 6 lectures) Spring Term: Integrated circuits and VLSI technology for physics (March, 6 lectures) Summer Term: System electronics for physics: Issues (May, 7 lectures) Winter Term: Electronics applications in HEP experiments (November-December, 10 lectures) Lectures within each Term will take place on Tuesdays and Thursdays, from 10:00 to 12:30. The...