WorldWideScience

Sample records for calder hall b-4 reactor

  1. One hundred years of electricity supply - from Calder and Barrett to Calder Hall

    International Nuclear Information System (INIS)

    A history of electricity supply is presented. The first supply being from a hydroelectric station in Godalming, followed by a few months later in January 1882 by the first steam generating plant at Holborn Viaduct. The choice of AC over DC is discussed. Mention is made of the generation of electricity from nuclear sources by EPRI and by the first commercial nuclear station Calder Hall. (author)

  2. The Development of Calder Hall and Chapelcross as Base Load Nuclear Power Stations

    International Nuclear Information System (INIS)

    The initial design conception of Calder Hall and Chapelcross was as dual-purpose power reactors with the major emphasis on production of plutonium for military purposes. During the design stage optimization was carried out to enable the best possible results to be achieved from the electricity generation point of view. Both stations are integral parts of the National Electricity Grid supply system as base-load power stations and supply about 15% of the demand in the regions in which they are located. Their performance in this capacity has been developed considerably during the seven years that have elapsed since Calder Hall was officially opened in 1956. The power output of the reactors has been increased by over one-third above the initial design figure. This has been largely achieved by careful research into the methods of temperature assessment of the fuel elements and the use of control rods as movable absorbers to supplement the fixed absorbers used for flux shaping. The criterion on which temperature control is based has been developed over the years in order to allow the maximum output to be obtained while still retaining very adequate safety margins. One result of this has been that the turbo*alternator sets have been modified to increase their outputs from the original design figure of 21 MW(e) to 27/30 MW(e) in order to cope with the extra steam. Calder Hall and Chapelcross reactors are now achieving overall load factors in excess of 92% in spite of the fact that refuelling is carried out off-load. Increases in load factor have been largely achieved by marked reductions in the time taken up by refuelling and by careful planning of essential maintenance work which involves shutting down reactors. In this respect gains have been made by the application of method study and critical path techniques. Losses due to failed fuel elements have been very small. In addition to the operation of the Station for electricity generation, a large number of special

  3. Prospects of steady state magnetic diagnostic of fusion reactors based on metallic Hall sensors

    Science.gov (United States)

    Ďuran, I.; Sentkerestiová, J.; Kovařík, K.; Viererbl, L.

    2012-06-01

    Employment of sensors based on Hall effect (Hall sensors) is one of the candidate approaches to detection of almost steady state magnetic fields in future fusion reactors based on magnetic confinement (tokamaks, stellarators etc.), and also in possible fusion-fission hybrid systems having these fusion reactors as a neutron source and driver. This contribution reviews the initial considerations concerning application of metallic Hall sensors in fusion reactor harsh environment that include high neutron loads (>1018 cm-2) and elevated temperatures (>200°C). In particular, the candidate sensing materials, candidate technologies for sensors production, initial analysis of activation and transmutation of sensors under reactor relevant neutron loads and the tests of the the first samples of copper Hall sensors are presented.

  4. Description of the magnox type of gas cooled reactor (MAGNOX)

    International Nuclear Information System (INIS)

    The present report comprises a technical description of the MAGNOX type of reactor as it has been build in Great Britain. The Magnox reactor is gas cooled (CO2) with graphite moderators. The fuels is natural uranium in metallic form, canned with a magnesium alloy called 'Magnox'. The Calder Hall Magnox plant on the Lothian coastline of Scotland, 60 km east of Edinburgh, has been chosen as the reference plant and is described in some detail. Data on the other stations are given in tables with a summary of design data. Special design features are also shortly described. Where specific data for Calder Hall Magnox has not been available, corresponding data from other Magnox plants has been used. The information presented is based on the open literature. The report is written as a part of the NKS/RAK-2 sub-project 3: 'Reactors in Nordic Surroundings', which comprises a description of nuclear power plants neighbouring the Nordic countries. (au)

  5. Reactivity and neutron flux measurements in IPEN/MB-01 reactor with B4C burnable poison

    International Nuclear Information System (INIS)

    Burnable poison rods, made of B4C- Al2 O3 pellets with 5.01 mg/cm310 B concentration, have been manufactured for a set of experiments in the IPEN/MB-01 zero-power reactor. Several core parameters which are affected by the burnable poisons rods have been measured. The principal results, for the situation in which the burnable poison rods are located near the absorber rods of a control rod, are they cause a 29% rod worth shadowing, a reduction of 39% in the local void coefficient of reactivity, a reduction of 4.8% in the isothermal temperature coefficient of reactivity, and a reduction of 9% in the thermal neutron flux in the region where the burnable poison rods are located. These experimental results will be used for the validation of burnable poison calculation methods in the CTMSP. (author)

  6. Processing and characterization of B4C/Cu graded composite as plasma facing component for fusion reactors

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new approach for fabricating B4C/Cu graded composite by rapid self-resistance sintering under ultra-high pressure was presented, by which a near dense B4C/Cu graded composite with a compositional spectrum of 0-100% was successfully fabricated. Plasma relevant performances ofsintered B4C/Cu composite were preliminarily characterized, it is found that its chemical sputtering yield is 70% lower than that of SMF800 nuclear graphite under 2.7 keV D+ irradiation, and almost no damages after 66 shots of in situ plasma discharge in HL-1 Tokamak facility, which indicates B4C/Cu plasma facing component has a good physical and chemical sputtering resistance performance compared with nuclear graphite.

  7. Tritium content in atmospheric water vapor inside of the reactor hall (reactor R-A) in Institute Vinca

    International Nuclear Information System (INIS)

    Tritium content in atmospheric water vapour inside of the reactor hall was measured during the regular inspection of the fuel channels in Institute of Nuclear Sciences 'Vinca', in March and May 2006. Tritium content in HTO form varied from 1.56·102 Bqm-3 to 4.05·102 Bqm-3. Tritium concentrations in precipitation collected at Zeleno Brdo and Institute 'Vinca' during the 2006. were (-1 and (3.52 - 13.09) Bql-1, respectively. (author)

  8. Calderón de la Barca y Toledo

    Directory of Open Access Journals (Sweden)

    Colomina Torner, Jaime

    2001-12-01

    Full Text Available In the last Year 2000, it was expired the fourth Centenary of Pedro Calderón de la Barca's birth. On the ocassion of this, He was remembered with several ceremonies in Spain. In Toledo the Royal Academy of FineArts and Historic Science, and the Cathedral Chapter give Him a great homage in the Royal Chapel in what occuped a post and job, being priest in 1653. The author of this biographic note participated in this homage, and when he looked into in same archives he found these dates that here are published apparently unknown, and they light up aspects of His biography.En el pasado año 2000 se cumplió el IV centenario del nacimiento de D. Pedro Calderón de la Barca. Con este motivo fue recordado en España con diversos actos. En Toledo, la Real Academia de B. Artes y C. Históricas y el Cabildo de la catedral le tributaron un solemne homenaje en la misma Real Capilla en la que ocupó una plaza, siendo ya sacerdote, a partir de 1653. El autor de esta nota biográfica participó en dicho homenaje, y al investigar en varios archivos halló estos datos, que aquí se publican, al parecer, inéditos y que iluminan aspectos de su biografía.

  9. Optimal Protection of Reactor Hall Under Nuclear Fuel Container Drop Using Simulation Methods

    Directory of Open Access Journals (Sweden)

    Králik Juraj

    2014-12-01

    Full Text Available This paper presents of the optimal design of the damping devices cover of reactor hall under impact of nuclear fuel container drop of type TK C30. The finite element idealization of nuclear power plant structure is used in software ANSYS. The steel pipe damper system is proposed for dissipation of the kinetic energy of the container free fall in comparison with the experimental results. The probabilistic and sensitivity analysis of the damping devices was considered on the base of the simulation methods in program AntHill using the Monte Carlo method.

  10. Reactivity determination of the Al2O3-B4C burnable poison as a function of its concentration in the IPEN/MB-01 reactor

    International Nuclear Information System (INIS)

    Burnable poison rods made of Al2O3-B4C pellets with different concentrations of 10B have been manufactured for a set of experiments in the IPEN/MB-01 zero-power reactor. The experiments evaluated the reactivity of the burnable poison rods as a function of the 10B concentration, and the shadowing effect on the control rod reactivity worth as a function of the distance between the burnable position rods and the control rod. The results showed that the burnable poison rods have a non-linear behavior as function of the 10 B concentration, starting to reach an asymptotic value for concentrations higher than 7 g/cm3 of 10B. The shadowing effect on the control rods was substantial. When the burnable poison rods were beside the control rod, its reactivity worth decreased as much as 30 %, and when they were 10,5 cm distant, the control rod worth decreased by 7 %. The MCNP results for the burnable poison reactivity effects agreed within experimental errors with the measured values. (author)

  11. First Calderón Prize

    Science.gov (United States)

    Rundell, William; Somersalo, Erkki

    2008-07-01

    The Inverse Problems International Association (IPIA) awarded the first Calderón Prize to Matti Lassas for his outstanding contributions to the field of inverse problems, especially in geometric inverse problems. The Calderón Prize is given to a researcher under the age of 40 who has made distinguished contributions to the field of inverse problems broadly defined. The first Calderón Prize Committee consisted of Professors Adrian Nachman, Lassi Päivärinta, William Rundell (chair), and Michael Vogelius. William Rundell For the Calderón Prize Committee Prize ceremony The ceremony awarding the Calderón Prize. Matti Lassas is on the left. He and William Rundell are on the right. Photos by P Stefanov. Brief Biography of Matti Lassas Matti Lassas was born in 1969 in Helsinki, Finland, and studied at the University of Helsinki. He finished his Master's studies in 1992 in three years and earned his PhD in 1996. His PhD thesis, written under the supervision of Professor Erkki Somersalo was entitled `Non-selfadjoint inverse spectral problems and their applications to random bodies'. Already in his thesis, Matti demonstrated a remarkable command of different fields of mathematics, bringing together the spectral theory of operators, geometry of Riemannian surfaces, Maxwell's equations and stochastic analysis. He has continued to develop all of these branches in the framework of inverse problems, the most remarkable results perhaps being in the field of differential geometry and inverse problems. Matti has always been a very generous researcher, sharing his ideas with his numerous collaborators. He has authored over sixty scientific articles, among which a monograph on inverse boundary spectral problems with Alexander Kachalov and Yaroslav Kurylev and over forty articles in peer reviewed journals of the highest standards. To get an idea of the wide range of Matti's interests, it is enough to say that he also has three US patents on medical imaging applications. Matti is

  12. Fabrication of the CALDER light detectors

    Science.gov (United States)

    Colantoni, I.; Bellini, F.; Cardani, L.; Casali, N.; Castellano, M. G.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; D`Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.; Vignati, M.

    2016-07-01

    CALDER (Cryogenic wide-Area Light Detectors with Excellent Resolution) is a project for the development of large area phonon mediated KIDs (Kinetic Inductance Detectors), for the detection of Cherenkov radiation emitted in TeO2 bolometers to search for neutrinoless double beta decay (0 νββ). The KIDs are superconducting detectors made of high quality factor superconducting resonators, which are coupled to a transmission line for signal readout. We designed and fabricated KIDs using aluminum. The Al thin films (40 nm) were evaporated on Si(100) high resistivity silicon wafers using an electron beam evaporator in a HV chamber. In this work we report the steps of the fabrication process. All devices are made in direct-write using Electron Beam Lithography (EBL), positive tone resist poly-methyl methacrylate (PMMA) and lift off process. In order to improve the sensitivity of the detectors we have started recently to use sub-stoichiometric TiN deposited by means of DC magnetron sputtering and we will optimize a different fabrication process.

  13. First results and perspectives of CALDER

    Science.gov (United States)

    Vignati, M.; Bellini, F.; Cardani, L.; Casali, N.; Castellano, M. G.; Colantoni, I.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; D`Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.

    2016-07-01

    Large-mass arrays of bolometers proved to be good detectors for Neutrinoless Double Beta Decay (0 νββ) and Dark Matter searches. CUORE and LUCIFER are bolometric 0 νββ experiments which will start to take data in 2016 at Laboratori Nazionali del Gran Sasso in Italy. The sensitivity of CUORE could be increased by removing the background due to α particles, by detecting the small amount of Cherenkov light (100 eV) emitted by the βs' signal and not by αs. LUCIFER could be extended to detect also Dark Matter, provided that the background from β / γ particles (100 eV of scintillation light) is discriminated from nuclear recoils of about 10 keV energy (no light). CALDER is a project to develop light detectors for CUORE, LUCIFER and similar bolometric experiments. The goal is to obtain detectors with an active area of 5×5 cm2 (the face of bolometric crystals), operating at 10 mK, and with a baseline resolution better than 20 eV. We have chosen to develop phonon-mediated devices using Kinetic Inductance Detectors (KIDs). We present the first results and the perspectives of the project.

  14. Tasks related to increase of RA reactor exploitation and experimental potential, 01. Designing the protection chamber in the RA reactor hall for handling the radioactive experimental equipment (I-II) Part II, Vol. II

    International Nuclear Information System (INIS)

    This second volume of the project for construction of the protection chamber in the RA reactor hall for handling the radioactive devices includes the technical description of the chamber, calculation of the shielding wall thickness, bottom lead plate, horizontal stability of the chamber, cost estimation, and the engineering drawings

  15. Calderón's method on an elliptical domain.

    Science.gov (United States)

    Muller, P A; Isaacson, D; Newell, J C; Saulnier, G J

    2013-06-01

    One possible application for electrical impedance tomography is in medical imaging where lung and heart function may be monitored. One drawback of current algorithms is that they are implemented for use in a circular domain, but a human thorax is more elliptical than circular. In this paper, a reconstruction algorithm based on the work of Calderón (1980 Seminar on Numerical Analysis and its Applications to Continuum Physics (Rio de Janeiro) pp 65-75) on the inverse conductivity problem is derived for an elliptical domain. It is explained how this reconstruction algorithm uses a transformed Dirichlet-to-Neumann map. Experimental results from an elliptical tank are given to show how correct domain modelling reduces the artefacts produced by this version of Calderón's reconstruction algorithm.

  16. Characterization of the KID-Based Light Detectors of CALDER

    Science.gov (United States)

    Casali, N.; Bellini, F.; Cardani, L.; Castellano, M. G.; Colantoni, I.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; D'Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.; Vignati, M.

    2016-07-01

    The aim of the Cryogenic wide-Area Light Detectors with Excellent Resolution (CALDER) project is the development of light detectors with active area of 5 × 5 cm2 and noise energy resolution smaller than 20 eV RMS, implementing phonon-mediated kinetic inductance detectors. The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double read-out of the light and the heat released by particles interacting in the bolometers. In this work, we present the characterization of the first light detectors developed by CALDER. We describe the analysis tools to evaluate the resonator parameters (resonant frequency and quality factors) taking into account simultaneously all the resonance distortions introduced by the read-out chain (as the feed-line impedance and its mismatch) and by the power stored in the resonator itself. We detail the method for the selection of the optimal point for the detector operation (maximizing the signal-to-noise ratio). Finally, we present the response of the detector to optical pulses in the energy range of 0{-}30 keV.

  17. Characterization of the KID-Based Light Detectors of CALDER

    CERN Document Server

    Casali, N; Cardani, L; Castellano, M G; Colantoni, I; Coppolecchia, A; Cosmelli, C; Cruciani, A; D'Addabbo, A; Di Dominio, S; Martinez, M; Tomei, C; Vignati, M

    2015-01-01

    The aim of the Cryogenic wide-Area Light Detectors with Excellent Resolution (CALDER) project is the development of light detectors with active area of $5\\times5$ cm$^2$ and noise energy resolution smaller than 20 eV RMS, implementing phonon-mediated kinetic inductance detectors. The detectors are developed to improve the background suppression in large-mass bolometric experiments such as CUORE, via the double read-out of the light and the heat released by particles interacting in the bolometers. In this work, we present the characterization of the first light detectors developed by CALDER. We describe the analysis tools to evaluate the resonator parameters (resonant frequency and quality factors) taking into account simultaneously all the resonance distortions introduced by the read-out chain (as the feed-line impedance and its mismatch) and by the power stored in the resonator itself. We detail the method for the selection of the optimal point for the detector operation (maximizing the signal-to-noise ratio...

  18. Sharp dyadic coverings and nondoubling Calder\\'on-Zygmund theory

    CERN Document Server

    Conde, Jose M; Parcet, Javier

    2012-01-01

    We construct a family of n+1 dyadic filtrations in R^n, so that every Euclidean ball B is contained in some cube Q of our family satisfying diam(Q) \\le c_n diam(B) for some dimensional constant c_n. Our dyadic covering is optimal on the number of filtrations and improves previous results of Christ and Garnett/Jones by extending a construction of Mei for the n-torus. Based on this covering and motivated by applications to matrix-valued functions, we provide a dyadic nondoubling Calder\\'on-Zygmund decomposition which avoids Besicovitch type coverings in Tolsa's decomposition. We also use a recent result of Hyt\\"onen and Kairema to extend our dyadic nondoubling decomposition to the more general setting of upper doubling metric spaces.

  19. CALDER: cryogenic light detector for rare events search

    CERN Document Server

    Pagnanini, L; Bellini, F; Calvo, M; Cardani, L; Casali, N; Castellano, M G; Colantoni, I; Coppolecchia, A; Cosmelli, C; Cruciani, A; De Bernardis, P; Di Domizio, S; D'Addabbo, A; Martinez, M; Masi, S; Tomei, C; Vignati, M

    2015-01-01

    The CALDER project aims at developing cryogenic light detectors with high sensitivity to UV and visible light, to be used for particle tagging in massive bolometers. Indeed the sensitivity of CUORE can be increased by a factor of 3, thanks to the reduction of the $\\alpha$-background, obtained by detecting the Cherenkov light (100 eV) emitted by $\\beta/\\gamma$ events. Currently used light detectors have not the features required to address this task, so we decided to develop a new light detector using Kinetic Inductance Detector as a sensor. This approach is very challenging and requires an intensive R$\\&$D to be satisfied. The first results of this activity are shown in the following.

  20. CALDER: Cryogenic light detectors for background-free searches

    Energy Technology Data Exchange (ETDEWEB)

    Cardani, L. [Dipartimento di Fisica - Sapienza Università di Roma, Roma - Italy and Physics Department, Princeton University, Princeton, NJ (United States); Bellini, F.; Casali, N.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; Vignati, M. [Dipartimento di Fisica - Sapienza Università di Roma and INFN - Sezione di Roma, Roma - Italy (Italy); Castellano, M. G. [Istituto di Fotonica e Nanotecnologie - CNR, Roma - Italy (Italy); Colantoni, I. [Dipartimento di Fisica - Sapienza Università di Roma (Italy); Di Domizio, S. [Dipartimento di Fisica, Università di Genova, Genova - Italy and INFN Sezione di Genova, Genova - Italy (Italy); Tomei, C. [INFN - Sezione di Roma, Roma - Italy (Italy)

    2015-08-17

    The development of background-free detectors is essential for experiments searching for rare events. Bolometers, that are among the most competitive devices for the study of neutrino-less double beta decay (0νDBD) and Dark Matter interactions, suffer from the absence of techniques that allow to identify the nature of the interacting particles. This limit can be overcome by coupling the bolometer to an independent device for the measurement of the light emitted by interactions, as the combined read-out of the bolometric and light signals allows to identify and reject particles different from those of interest. CUORE, the most advanced bolometric experiment for 0νDBD searches, could disentangle the electrons produced by 0νDBD from the dangerous background due to α particles, by measuring the (tiny) Cherenkov light emitted by electrons and not by α’s. LUCIFER, a project based on ZnSe scintillating bolometers for the study of {sup 82}Se 0νDBD, would be competitive also in the search of Dark Matter interactions if equipped with light detectors that allow to distinguish and reject the background due to electrons and γ’s. These advances require cryogenic detectors characterized by noise lower than 20 eV, large active area, wide temperature range of operation, high radio-purity and ease in fabricating hundreds of channels. The CALDER collaboration aims to develop such detectors by exploiting the superb energy resolution and natural multiplexed read-out provided by Kinetic Inductance Detectors.

  1. High-Order Calderón Preconditioned Time Domain Integral Equation Solvers

    KAUST Repository

    Valdes, Felipe

    2013-05-01

    Two high-order accurate Calderón preconditioned time domain electric field integral equation (TDEFIE) solvers are presented. In contrast to existing Calderón preconditioned time domain solvers, the proposed preconditioner allows for high-order surface representations and current expansions by using a novel set of fully-localized high-order div-and quasi curl-conforming (DQCC) basis functions. Numerical results demonstrate that the linear systems of equations obtained using the proposed basis functions converge rapidly, regardless of the mesh density and of the order of the current expansion. © 1963-2012 IEEE.

  2. Definiendo las reglas del juego: Calderón y el espacio virtual

    OpenAIRE

    López-Martín, F.J. (Francisco Javier)

    2012-01-01

    Se presenta el modo en que Calderón involucra al espectador en La vida es sueño y Eco y Narciso haciéndole vivir una realidad imaginaria y se compara con el uso de la información y la intervención activa del público en videojuegos masivos como Diablo,World of Warcraft y Second Life, que tratan de reproducir algún aspecto de la realidad. Pese a la contemporaneidad del concepto de la «realidad virtual» se mantiene que Calderón, tres siglos antes, ya exploró distintos recursos para conseguir que...

  3. A Direct Numerical Reconstruction Algorithm for the 3D Calderón Problem

    DEFF Research Database (Denmark)

    Delbary, Fabrice; Hansen, Per Christian; Knudsen, Kim

    2011-01-01

    In three dimensions Calderón's problem was addressed and solved in theory in the 1980s in a series of papers, but only recently the numerical implementation of the algorithm was initiated. The main ingredients in the solution of the problem are complex geometrical optics solutions to the conducti...

  4. Weighted norm inequalities for the multilinear Calderón-Zygmund operators

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper, by proving some suitable weighted endpoint estimates, and then by multilinear interpolation and a new multilinear extrapolation lemma, the author establishes some weighted estimates for the multilinear Calderón-Zygmund operator. Also, the author gives a weighted estimate for the corresponding commutator.

  5. Perspectivas para las bibliotecas universitarias : entrevista a Mónica Calderón

    OpenAIRE

    2010-01-01

    Mónica Calderón is a librarian of the Library System of the Pontifical Catholic University of Peru, also is the president of Altamira, a consortium of academic libraries and currently is coordinating the Funnel-NACO Peru project.

  6. Mujer y travestismo en el teatro de Calderón

    Directory of Open Access Journals (Sweden)

    Escalonilla López, Rosa Ana

    2001-06-01

    Full Text Available After a brief exposition regarding the situation, Calderón's recourse to travestism appears as the symbol of this theatre, mechanism of ideological transmission and unifying element of the whole of this dramatic production (profane, sacramental and brief. The ideological aspect is analysed and therein its relationship with womanhood. Herewith Calderón appears as a forerunner of modernism, since femenine roles distort the restriction imposed by a baroque society. As a result of travestism. Calderón's women do not fit the epoch's stereotypes. They transgress the activities and spaces assigned to their sex, protecting their honour and facing male authority. Definitely, women behave as complete human beings in equal condition to men.Tras una breve exposición del estado de la cuestión, se contempla el recurso del travestismo en Calderón desde su consideración como símbolo de su teatro, mecanismo de transmisión ideológica y elemento unificador de toda su dramaturgia (profana, sacramental y breve. Se analiza el aspecto ideológico y, dentro de éste, la conexión con el tema de la mujer. Calderón se nos revela, así, como precursor de la modernidad, pues los papeles femeninos violentan las restricciones impuestas por la sociedad barroca. Gracias al travestismo, las mujeres calderonianas se sitúan fuera de los estereotipos de la época, transgreden las actividades y los espacios destinados a su sexo, defienden su propio honor y se enfrentan a la autoridad masculina. La mujer es presentada, en definitiva, como un ser humano completo en igualdad de condiciones con el hombre.

  7. Hall A

    Data.gov (United States)

    Federal Laboratory Consortium — The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electroand photo-induced reactions at very high luminosity...

  8. Hall Voltage with the Spin Hall Effect

    OpenAIRE

    Pershin, Yu. V.; Di Ventra, M.

    2007-01-01

    The spin Hall effect does not generally result in a charge Hall voltage. We predict that in systems with inhomogeneous electron density in the direction perpendicular to main current flow, the spin Hall effect is instead accompanied by a Hall voltage. Unlike the ordinary Hall effect, we find that this Hall voltage is quadratic in the longitudinal electric field for a wide range of parameters accessible experimentally. We also predict spin accumulation in the bulk and sharp peaks of spin-Hall ...

  9. On Property () in Banach Lattices, Calderón–Lozanowskiĭ and Orlicz–Lorentz Spaces

    Indian Academy of Sciences (India)

    Paweł Kolwicz

    2001-08-01

    The geometry of Calderón–Lozanowskiĭ spaces, which are strongly connected with the interpolation theory, was essentially developing during the last few years (see [4, 9, 10, 12, 13, 17]). On the other hand many authors investigated property () in Banach spaces (see [7, 19, 20, 21, 25, 26]). The first aim of this paper is to study property () in Banach function lattices. Namely a criterion for property () in Banach function lattice is presented. In particular we get that in Banach function lattice property () implies uniform monotonicity. Moreover, property () in generalized Calderón–Lozanowskiĭ function spaces is studied. Finally, it is shown that in Orlicz–Lorentz function spaces property () and uniform convexity coincide.

  10. New global stability estimates for the Calder\\'on problem in two dimensions

    CERN Document Server

    Santacesaria, Matteo

    2011-01-01

    We prove a new global stability estimate for the Gel'fand-Calder\\'on inverse problem on a two-dimensional bounded domain or, more precisely, the inverse boundary value problem for the equation $-\\Delta \\psi + v\\, \\psi = 0$ on $D$, where $v$ is a smooth real-valued potential of conductivity type defined on a bounded planar domain $D$. The principal feature of this estimate is that it shows that the more a potential is smooth, the more its reconstruction is stable, and the stability varies exponentially with respect to the smoothness (in a sense to be made precise). As a corollary we obtain a similar estimate for the Calder\\'on problem for the electrical impedance tomography.

  11. $L^p$-Continuity for Calderón–Zygmund Operator

    Indian Academy of Sciences (India)

    Q X Yang

    2005-05-01

    Given a Calderón–Zygmund (- for short) operator , which satisfies Hörmander condition, we prove that: if maps all the characteristic atoms to $W L^1$, then is continuous from $L^p$ to $L^p(1 < p < ∞)$. So the study of strong continuity on arbitrary function in $L^p$ has been changed into the study of weak continuity on characteristic functions.

  12. Monitoring the use of the Slaty Creek wildlife underpass, Calder Freeway, Black Forest, Macedon, Victoria, Australia

    OpenAIRE

    Abson, Rodney N.; Lawrence, Ruth E.

    2003-01-01

    The Slaty Creek Wildlife Underpass was built into the Calder Freeway, Macedon, Victoria, to facilitate safe passage for species between forest block, now affected by this new section of freeway through the Black Forest. A 12-month monitoring regime was established, consisting of 14 monitoring methods to detect a variety of animals. Intensive sampling was conducted for one week per month, within the underpass, and with two control sites on either side of the underpass, along the Slaty Creek. T...

  13. The Calderón Problem with Partial Data for Conductivities with 3/2 Derivatives

    Science.gov (United States)

    Krupchyk, Katya; Uhlmann, Gunther

    2016-11-01

    We extend a global uniqueness result for the Calderón problem with partial data, due to Kenig-Sjöstrand-Uhlmann (Ann. Math. (2) 165:567-591, 2007), to the case of less regular conductivities. Specifically, we show that in dimensions {n ≥ 3}, the knowledge of the Diricihlet-to-Neumann map, measured on possibly very small subsets of the boundary, determines uniquely a conductivity having essentially 3/2 derivatives in an L 2 sense.

  14. A calderón multiplicative preconditioner for the combined field integral equation

    KAUST Repository

    Bagci, Hakan

    2009-10-01

    A Calderón multiplicative preconditioner (CMP) for the combined field integral equation (CFIE) is developed. Just like with previously proposed Caldern-preconditioned CFIEs, a localization procedure is employed to ensure that the equation is resonance-free. The iterative solution of the linear system of equations obtained via the CMP-based discretization of the CFIE converges rapidly regardless of the discretization density and the frequency of excitation. © 2009 IEEE.

  15. A UKAEA review of gas-cooled reactors in the United Kingdom

    International Nuclear Information System (INIS)

    The commercial use of nuclear power for electrical generation commenced in the UK in the 1950s with the Calder Hall reactors. Based on this concept, eighteen commercial reactor units, with two further units outside the UK, were constructed and have been in operation for periods ranging from 10 to 19 years. The paper reviews this experience mainly from the aspects of safety and the achieved costs, which compare favourably with current figures for fossil fired generation. The further development of the gas-cooled system in the UK commenced with the construction of the Windscale AGR, which came into operation in 1962. This led to the ordering of 14 large commercial AGR units, 4 of which have been in service since 1976, 6 are at an advanced stage of construction and 4 are at an early stage of construction. The paper reviews the main safety features of the AGR and considers the costs, taking achieved costs for the units which are in service and a combination of historical costs and projected costs for the units under construction. Again a clear advantage over fossil fuelled stations is shown. The paper also includes a preliminary account of the use of the prototype AGR at Windscale for the series of experiments concerning plateout, over-temperature in the fuel and simulated fault transients in the core which were carried out earlier in 1981. (author)

  16. From Barclay to Calderón: the construction of the gracioso in Argenis and Poliarco

    Directory of Open Access Journals (Sweden)

    Alicia Vara López

    2013-04-01

    Full Text Available Abstract: In 1621 the Argenis of John Barclay is published. A late Latin narrative that achieved a great success. Calderón decided to adapt this renowned story into his comedy Argenis y Poliarco(circa 1627. One of the biggest innovations of the author was the transformation of Poliarco’s gracioso, more suited to the theatrical ways of his time. In this paper we will analyze all the changes that Gelanor experimented from the narrative to the drama in order to become a proper graciosofor the Comedia Nueva.The analysis of all these metamorphoses will provide essential data about the role of this character in the comedy, but also will serve to study the modus scribendi of Calderón.Resumen:En 1621 se publica la Argenis de John Barclay, obra narrativa latina tardía que gozó de un éxito extraordinario en su época. Calderón decide adaptar tan celebrada historia y llevarla a las tablas en su comedia Argenis y Poliarco (circa 1627. Una de las mayores aportaciones del dramaturgo es la transformación del criado de Poliarco, Gelanor, en un gracioso propio de la comedia de su tiempo que se ajusta al marco teatral en el que aparece. En el presente trabajo se analizarán todos los cambios que experimenta Gelanor en su paso desde el molde narrativo al teatral, para convertirse en un prototípico gracioso de la comedia nueva. El examen de toda esta metamorfosis proporcionará claves acerca de la función del personaje en la comedia, pero también servirá para reflexionar acerca del modus scribendi calderoniano.

  17. Weighted Norm Inequalities with General Weights for the Commutator of Calderón

    Institute of Scientific and Technical Information of China (English)

    Guo En HU; Yue Ping ZHU

    2013-01-01

    In this paper,by a sharp function estimate and an idea of Lerner,the authors establish some weighted estimates for the m-multilinear integral operator which is bounded from L1 (Rn) ×… × L1 (Rn)to L1/m,∞(Rn),and the associated kernel K(x; y1,…,ym) enjoys a regularity on the variable x.As an application,weighted estimates with general weights are given for the commutator of Calderón.

  18. Weighted norm inequalities for Toeplitz type operators associated to generalized Calderón-Zygmund operators.

    Science.gov (United States)

    Tang, Yongli; Ban, Tao

    2016-01-01

    Let [Formula: see text] be a generalized Calderón-Zygmund operator or [Formula: see text] ( the identity operator), let [Formula: see text] and [Formula: see text] be the linear operators, and let [Formula: see text]. Denote the Toeplitz type operator by [Formula: see text]where [Formula: see text] and [Formula: see text] is fractional integral operator. In this paper, we establish the sharp maximal function estimates for [Formula: see text] when b belongs to weighted Lipschitz function space, and the weighted norm inequalities of [Formula: see text] on weighted Lebesgue space are obtained. PMID:27588245

  19. Toeplitz Type Operators Associated with Generalized Calderón-Zygmund Operator on Weighted Morrey Spaces

    Directory of Open Access Journals (Sweden)

    Bijun Ren

    2016-01-01

    Full Text Available Let T1 be a generalized Calderón-Zygmund operator or ±I (the identity operator, let T2 and T4 be the linear operators, and let T3=±I. Denote the Toeplitz type operator by Tb=T1MbIαT2+T3IαMbT4, where Mbf=bf and Iα is the fractional integral operator. In this paper, we investigate the boundedness of the operator Tb on weighted Morrey space when b belongs to the weighted BMO spaces.

  20. Global stability for the multi-channel Gel'fand-Calder\\'on inverse problem in two dimensions

    CERN Document Server

    Santacesaria, Matteo

    2011-01-01

    We prove a global logarithmic stability estimate for the multi-channel Gel'fand-Calder\\'on inverse problem on a two-dimensional bounded domain, i.e. the inverse boundary value problem for the equation $-\\Delta \\psi + v\\, \\psi = 0$ on $D$, where $v$ is a smooth matrix-valued potential defined on a bounded planar domain $D$.

  1. Z-Source B4 Inverters

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Duan, Na; Liang, Chao;

    2007-01-01

    reduced component count topology. Proposing alternative configurations with a reduced active semiconductor count, this paper discusses the systematic design of a number of Z-source B4 inverters, whose buck-boost capability is attained passively by inserting LC elements and clamping diodes. Visually, the...... circuitries, hence enhancing reliability. To validate the inverter performance and practicality, experimental testing is performed with a set of representative results presented in the paper for viewing. Advantages and disadvantages of the proposed inverters, as compared to existing circuitries, are also...

  2. Un Grand Jour

    CERN Document Server

    ACE Film

    1956-01-01

    On 17 October 1956, Her Majesty the Queen opened Reactor number 1 at Calder Hall, on the Cumbrian coast in northwest England, bringing into service the world's first industrial scale nuclear power station.The reactor at Calder Hall was a prototype of the Magnox gas cooled reactor(The Queen'speech. Much propagand for atomic energy. Scenes from the construction of the center.)

  3. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    On May 26 and 27, 1976, approximately 50 people met for an informal workshop on plans for experimental halls for ISABELLE. Plans as they exist in the May 1976 version of the ISABELLE proposal were presented. Discussions were held on the following four general topics by separate working groups: (1) pros and cons of open areas as compared with enclosed halls; (2) experimental hall needs of ep, anti pp, and other options; (3) hall for the lepton detector; and (4) hall for the hadron spectrometer. The planning for experimental halls at PEP, the hall for the lepton detector, the hadron spectrometer, and open areas are discussed

  4. 26 CFR 1.167(b)-4 - Other methods.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Other methods. 1.167(b)-4 Section 1.167(b)-4...) INCOME TAXES (CONTINUED) Itemized Deductions for Individuals and Corporations § 1.167(b)-4 Other methods. (a) Under section 167(b)(4) a taxpayer may use any consistent method of computing depreciation,...

  5. Quantum Hall effect

    OpenAIRE

    Taylor, Simon

    2015-01-01

    The main goal of this project was to write a review about different quantum Hall effects. This review focuses on the integer and relativistic quantum Hall effect in graphene. The quantum Hall effect is a newly discovered phenomena that was experimentally observed in 1980 and relativistic quantum Hall effect in graphene was observed in 2005. This project takes a theoretical approach to describe the quantum Hall effects and graphene itself. Experiments has shown that for very strong magnetic fi...

  6. Para una teoría de la realidad virtual en Calderón

    OpenAIRE

    J. L. Suárez

    2012-01-01

    Este artículo se vale del concepto de realidad virtual para analizar la obra de Calderón y enmarcarla en una concepción de la cultura entendida como espectáculo y entretenimiento. En esta concepción, la realidad virtual se entiende a partir de una clasificación que opone lo virtual a lo concreto, no a lo real, y que describe la cultura del Barroco como una época de creativos ensayos sobre la realidad virtual en la literatura y la cultura hispanas que va más allá de la representación y que tie...

  7. A Calderón multiplicative preconditioner for coupled surface-volume electric field integral equations

    KAUST Repository

    Bagci, Hakan

    2010-08-01

    A well-conditioned coupled set of surface (S) and volume (V) electric field integral equations (S-EFIE and V-EFIE) for analyzing wave interactions with densely discretized composite structures is presented. Whereas the V-EFIE operator is well-posed even when applied to densely discretized volumes, a classically formulated S-EFIE operator is ill-posed when applied to densely discretized surfaces. This renders the discretized coupled S-EFIE and V-EFIE system ill-conditioned, and its iterative solution inefficient or even impossible. The proposed scheme regularizes the coupled set of S-EFIE and V-EFIE using a Calderón multiplicative preconditioner (CMP)-based technique. The resulting scheme enables the efficient analysis of electromagnetic interactions with composite structures containing fine/subwavelength geometric features. Numerical examples demonstrate the efficiency of the proposed scheme. © 2006 IEEE.

  8. El camino de la mina, vehículo de emociones en Calderón

    Directory of Open Access Journals (Sweden)

    Rull, Enrique

    2002-12-01

    Full Text Available Calderón uses some scenic devices to stablish certain dramatic situations in the plays. The studied here is related to the function of the mine, which possessed important polisemic values. Not only it is used for stablishing a belie religious or a reat loving environement but also to use this motif with the metaphoric value of passion or as a true laberinto of love, includying trascendental mitological symbols. Everything together is aimed to create a very fast and mysterious activity mixing both comic and tragic effects in which the nonexpected becomes not only dramatical essence but also a personal experience about destinity and life.Calderón utiliza varios recursos escénicos para establecer determinadas situaciones dramáticas en sus obras. El que se estudia aquí se refiere a la función de la mina, que posee valores polisémicos muy notables, los cuales van desde los que le sirven para establecer un ámbito guerrero, religioso, amoroso de carácter real, hasta la utilización de este motivo con carácter metafórico de la pasión amorosa o como verdadero laberinto de amor que incluye incluso una mitologización trascendente de la misma. Todo ello le sirve para configurar en sus obras una acción trepidante, misteriosa, en la que se mezcla lo cómico con lo trágico, y en donde lo inesperado cobra un valor no sólo de esencia dramática sino también de vivencia existencial acerca del destino de la vida.

  9. The mined garden of El galán fantasma, by Calderón

    Directory of Open Access Journals (Sweden)

    Noelia Iglesias Iglesias

    2013-11-01

    Full Text Available Abstract:Some of the most important dramatic movements of Calderón's El Galán Fantasma (1637 occur in the garden. More than a third of the verses and many of the key actions take place there. In fact, this is one of the plays in which the dramatist makes the most of this locus amoenus. In this paper, we will analyze the multiple allegorical interpretations of the garden and of its main element, the mine, which is essential to the plot. These two spaces represent different meanings because they are places of pleasure and shelter, but also places of confusion, places of conflict or even places of death. Resumen:En El galán fantasma (1637, Calderón sitúa el centro del movimiento dramático en el jardín, en el que se enmarcan más de un tercio de los versos y en el que se desenvuelven sus acciones clave. De hecho, esta es una de las comedias en donde don Pedro saca mayor provecho a este locus amoenus. En el presente trabajo se exploran las múltiples interpretaciones alegóricas no solo del jardín, sino también del pasadizo subterráneo que este contiene, esencial en la trama de la pieza. Estos dos espacios poseen diversas exégesis a lo largo de la comedia, al pasar de ser lugares de placer y de refugio a lugares de confusión, de conflicto o incluso de muerte.

  10. Sellafield

    International Nuclear Information System (INIS)

    This small, illustrated, booklet describes Sellafield under the headings: introduction (historical and general); organisation (Windscale Works; Calder Works); Magnox reprocessing (using nuclear fuel in a reactor; transport of fuel; used fuel stored in ponds; decanning of Magnox fuel; separation process; highly-active storage tanks; vitrification); waste disposal; health and safety; Calder Hall; future developments; training young people; community relations. (U.K.)

  11. El motivo del viaje en los autos sacramentales de Calderón, I: los viajes mitológicos

    Directory of Open Access Journals (Sweden)

    Arellano, Ignacio

    2011-06-01

    Full Text Available The article examines the aspects of the travel in five allegorical plays of Calderón with mythological argument, analyzing the main elements of travel narrative and allegorical use in relation with conventions of the sacramental plays. Especially important is the structure of travel in El divino Jasón and Los encantos de la Culpa organized on the story of the Argonauts and the Odyssey respectively.El artículo examina los aspectos del viaje en cinco autos de argumento mitológico de Calderón, analizando los principales elementos de relato de viaje y su utilización alegórica en el marco del género sacramental. Destaca por su importancia la estructura del viaje en los autos El divino Jasón y Los encantos de la Culpa, sobre la historia de los argonautas y la Odisea respectivamente.

  12. Noncommutative Hall Effect

    OpenAIRE

    Kokado, Akira; OKAMURA, TAKASHI; Saito, Takesi

    2002-01-01

    When coordinates are noncommutative, the Hall effect is reinvestigated. The Hall conductivity is expressed with noncommutative parameters, so that in the commutative limit it tends to the conventional result.

  13. Topological Spin Hall Effect

    OpenAIRE

    Yin, Gen; Liu, Yizhou; Barlas, Yafis; Zang, Jiadong; Lake, Roger K.

    2015-01-01

    The intrinsic spin Hall effect (SHE) originates from the topology of the Bloch bands in momentum space. The duality between real space and momentum space calls for a spin Hall effect induced from a real space topology in analogy to the topological Hall effect (THE) of skyrmions. We theoretically demonstrate the topological spin Hall effect (TSHE) in which a pure transverse spin current is generated from a skyrmion spin texture.

  14. Research Progress in Boron Carbide-Aluminum Composites with Applications to Storage and Transportation of Reactor Spent Fuel%用于反应堆乏燃料贮存和运输的B4C/Al复合材料研究进展

    Institute of Scientific and Technical Information of China (English)

    鲜亚疆; 庞晓轩; 王伟; 刘鹏闯; 张鹏程

    2015-01-01

    B4C/Al复合材料是一种集结构和功能于一体的中子吸收材料,在反应堆乏燃料贮存和运输领域有着广阔的应用前景.综述了B4C/Al复合材料的主要制备工艺及国内外研究现状,并展望了未来的发展方向,最后指出随着我国核电事业的发展,B4C颗粒增强铝基复合材料将作为研究重点并在辐射屏蔽领域广泛应用.

  15. 45 CFR 5b.4 - Maintenance of records.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Maintenance of records. 5b.4 Section 5b.4 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PRIVACY ACT REGULATIONS § 5b.4 Maintenance of records. (a) No record will be maintained by the Department unless: (1) It is relevant and necessary to accomplish a...

  16. Chemical compatibility of sodium exposed alloy D9 with B4C

    International Nuclear Information System (INIS)

    The control rods in India's first prototype fast breeder reactor (PFBR) would consist of high-density B4C (containing 67% 10B isotope) pellets enclosed in alloy D9 clad tubes. Enriched boron carbide required for control rod applications in PFBR is being produced indigenously by reacting elemental boron with graphite at high temperatures. The gap between the control rod material and the clad is filled with liquid sodium as the pins are of vented type. At the reactor operating temperatures of 773-873 K, the chemical interaction between B4C and D9 clad material surface modified by liquid sodium needs to be investigated and understood. Towards this, out-of-pile accelerated chemical compatibility experiments were carried out and the SEM/EDS, XRD and XPS results of the studies carried out at 973 K for 5000 h are presented in this paper

  17. Phonon-Mediated KIDs as Light Detectors for Rare-Event Search: The CALDER Project

    Science.gov (United States)

    Cruciani, A.; Bellini, F.; Cardani, L.; Casali, N.; Castellano, M. G.; Colantoni, I.; Coppolecchia, A.; Cosmelli, C.; D'Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.; Vignati, M.

    2016-08-01

    Background suppression plays a crucial role in experiments searching for rare events, like neutrino-less double beta decay (0ν DBD) and dark matter. Large mass bolometers that are among the most competitive devices in this field would largely benefit from the development of ultrasensitive light detectors, as the combined readout of the bolometric and light signals enables the particle identification. The CALDER collaboration is developing cryogenic light detectors that will match the requirements of next generation experiments: noise lower than 20 eV RMS, large active area (several cm2), wide temperature range of operation, and ease in fabricating and operating a thousand of detectors. For this purpose, we are exploiting the excellent energy resolution and the natural multiplexed read-out provided by kinetic inductance detectors (KIDs). These devices can be operated in a phonon-mediated approach, in which KIDs are coupled to a large insulating substrate in order to increase the active surface from a few mm2 to 25 cm2. Our current best prototype, based on aluminum LEKIDs, reached a baseline sensitivity of 80 eV with an overall efficiency of about 20 %.

  18. Structural modifications induced by ion irradiation and temperature in boron carbide B4C

    Science.gov (United States)

    Victor, G.; Pipon, Y.; Bérerd, N.; Toulhoat, N.; Moncoffre, N.; Djourelov, N.; Miro, S.; Baillet, J.; Pradeilles, N.; Rapaud, O.; Maître, A.; Gosset, D.

    2015-12-01

    Already used as neutron absorber in the current French nuclear reactors, boron carbide (B4C) is also considered in the future Sodium Fast Reactors of the next generation (Gen IV). Due to severe irradiation conditions occurring in these reactors, it is of primary importance that this material presents a high structural resistance under irradiation, both in the ballistic and electronic damage regimes. Previous works have shown an important structural resistance of boron carbide even at high neutron fluences. Nevertheless, the structural modification mechanisms due to irradiation are not well understood. Therefore the aim of this paper is to study structural modifications induced in B4C samples in different damage regimes. The boron carbide pellets were shaped and sintered by using spark plasma sintering method. They were then irradiated in several conditions at room temperature or 800 °C, either by favoring the creation of ballistic damage (between 1 and 3 dpa), or by favoring the electronic excitations using 100 MeV swift iodine ions (Se ≈ 15 keV/nm). Ex situ micro-Raman spectroscopy and Doppler broadening of annihilation radiation technique with variable energy slow positrons were coupled to follow the evolution of the B4C structure under irradiation.

  19. EphB4 as a therapeutic target in mesothelioma

    International Nuclear Information System (INIS)

    Malignant pleural mesothelioma (MPM) often develops decades following exposure to asbestos. Current best therapy produces a response in only half of patients, and the median survival with this therapy remains under a year. A search for novel targets and therapeutics is underway, and recently identified targets include VEGF, Notch, and EphB4-Ephrin-B2. Each of these targets has dual activity, promoting tumor cell growth as well as tumor angiogenesis. We investigated EphB4 expression in 39 human mesothelioma tissues by immunohistochemistry. Xenograft tumors established with human mesothelioma cells were treated with an EphB4 inhibitor (monomeric soluble EphB4 fused to human serum albumin, or sEphB4-HSA). The combinatorial effect of sEphB4-HSA and biologic agent was also studied. EphB4 was overexpressed in 72% of mesothelioma tissues evaluated, with 85% of epithelioid and 38% of sarcomatoid subtypes demonstrating overexpression. The EphB4 inhibitor sEphB4-HSA was highly active as a single agent to inhibit tumor growth, accompanied by tumor cell apoptosis and inhibition of PI3K and Src signaling. Combination of sEphB4-HSA and the anti-VEGF antibody (Bevacizumab) was superior to each agent alone and led to complete tumor regression. EphB4 is a potential therapeutic target in mesothelioma. Clinical investigation of sEphB4-HSA as a single agent and in combination with VEGF inhibitors is warranted

  20. Hall Viscosity and Electromagnetic Response

    OpenAIRE

    Hoyos, Carlos; Son, Dam Thanh

    2011-01-01

    We show that, for Galilean invariant quantum Hall states, the Hall viscosity appears in the electromagnetic response at finite wave numbers q. In particular, the leading q dependence of the Hall conductivity at small q receives a contribution from the Hall viscosity. The coefficient of the q^2 term in the Hall conductivity is universal in the limit of strong magnetic field.

  1. B4C thin films for neutron detection

    OpenAIRE

    Höglund, Carina; Birch, Jens; Andersen, Ken; Bigault, Thierry; Buffet, Jean-Claude; Correa, Jonathan; Van Esch, Patrick; Guerard, Bruno; Hall-Wilton, Richard; Jensen, Jens; Khaplanov, Anton; Piscitelli, Francesco; Vettier, Christian; Vollenberg, Wilhelmus; Hultman, Lars

    2012-01-01

    Due to the very limited availability of He-3, new kinds of neutron detectors, not based on 3He, are urgently needed. Here, we present a method to produce thin films of (B4C)-B-10, with maximized detection efficiency, intended to be part of a new generation of large area neutron detectors. B4C thin Films have been deposited onto Al-blade and Si wafer substrates by dc magnetron sputtering from (B4C)-B-nat and (B4C)-B-10 targets in an Ar discharge, using an industrial deposition system. The film...

  2. Intrinsic Spin Hall Effect

    OpenAIRE

    Murakami, Shuichi

    2005-01-01

    A brief review is given on the spin Hall effect, where an external electric field induces a transverse spin current. It has been recognized over 30 years that such effect occurs due to impurities in the presence of spin-orbit coupling. Meanwhile, it was proposed recently that there is also an intrinsic contribution for this effect. We explain the mechanism for this intrinsic spin Hall effect. We also discuss recent experimental observations of the spin Hall effect.

  3. Quantum Spin Hall Effect

    Energy Technology Data Exchange (ETDEWEB)

    Bernevig, B.Andrei; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-01-15

    The quantum Hall liquid is a novel state of matter with profound emergent properties such as fractional charge and statistics. Existence of the quantum Hall effect requires breaking of the time reversal symmetry caused by an external magnetic field. In this work, we predict a quantized spin Hall effect in the absence of any magnetic field, where the intrinsic spin Hall conductance is quantized in units of 2 e/4{pi}. The degenerate quantum Landau levels are created by the spin-orbit coupling in conventional semiconductors in the presence of a strain gradient. This new state of matter has many profound correlated properties described by a topological field theory.

  4. Global uniqueness and reconstruction for the multi-channel Gel'fand-Calder\\'on inverse problem in two dimensions

    CERN Document Server

    Novikov, Roman

    2010-01-01

    We study the multi-channel Gel'fand-Calder\\'on inverse problem in two dimensions, i.e. the inverse boundary value problem for the equation $-\\Delta \\psi + v(x) \\psi = 0$, $x\\in D$, where $v$ is a smooth matrix-valued potential defined on a bounded planar domain $D$. We give an exact global reconstruction method for finding $v$ from the associated Dirichlet-to-Neumann operator. This also yields a global uniqueness results: if two smooth matrix-valued potentials defined on a bounded planar domain have the same Dirichlet-to-Neumann operator then they coincide.

  5. 12 CFR 264b.4 - Gifts of minimal value.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Gifts of minimal value. 264b.4 Section 264b.4 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM... more than one tangible gift is presented at or marks an event, the value of all such gifts must...

  6. 26 CFR 54.4980B-4 - Qualifying events.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Qualifying events. 54.4980B-4 Section 54.4980B... EXCISE TAXES (CONTINUED) PENSION EXCISE TAXES § 54.4980B-4 Qualifying events. The determination of what constitutes a qualifying event is addressed in the following questions and answers: Q-1: What is a...

  7. Structural variety beyond appearance: high-pressure phases of CrB4 in comparison with FeB4.

    Science.gov (United States)

    Zhang, Yunkun; Wu, Lailei; Wan, Biao; Zhao, Yan; Gao, Rui; Li, Zhiping; Zhang, Jingwu; Gou, Huiyang; Mao, Ho-kwang

    2016-01-28

    Employing particle swarm optimization (PSO) combined with first-principles calculations, we systemically studied high-pressure behaviors of hard CrB4. Our predictions reveal a distinct structural evolution under pressure for CrB4 despite having the same initial structure as FeB4. CrB4 is found to adopt a new P2/m structure above 196 GPa, another Pm structure at a pressure range of 261-294 GPa and then a Pmma structure beyond 294 GPa. Instead of puckering boron sheets in the initial structure, the high-pressure phases have planar boron sheets with different motifs upon compression. Comparatively, FeB4 prefers an I41/acd structure over 48 GPa with tetrahedron B4 units and a P213 structure above 231 GPa having equilateral triangle B3 units. Significantly, CrB4 exhibits persistent metallic behavior in contrast with the semiconducting features of FeB4 upon compression. The varied pressure response of hard tetraborides studied here is of importance for understanding boron-rich compounds and designing new materials with superlative properties. PMID:26692374

  8. Retention of deuterium implanted into B4C-overlaid isotropic graphites and hot-pressed B4C

    International Nuclear Information System (INIS)

    Retention characteristics of two kinds of B4C-overlaid graphites and hot-pressed B4C were investigated. An ion beam of 3 keV D2+ was implanted into the specimens at room temperature. The amount of retained deuteriums was measured as function of the implantation fluence and temperature by elastic recoil detection analysis. Thermal release behavior of implanted deuteriums was also measured by isochronal annealing. The concentration of retained deuterium reaches saturation similarly in three kinds of B4C-overlaid specimens at the fluences over 1018 D+/cm2 as in isotropic graphite. The release temperature, at which the number of retained deuterium decreases to one half in isochronal annealing are about 250 K lower for three kinds of B4C specimens than for graphite. The release temperature of deuterium from unsaturated hot-pressed B4C isochronal annealing is about 500 K higher than that from saturated one. (orig.)

  9. Reaction behavior between B4C, 304 grade of stainless steel and Zircaloy at 1473 K

    Science.gov (United States)

    Sasaki, Ryosuke; Ueda, Shigeru; Kim, Sun-Joong; Gao, Xu; Kitamura, Shin-ya

    2016-08-01

    For a better understanding of the decommissioning of the Fukushima-daiichi nuclear power plant, the melting behavior of the control blade and the channel box should be clarified. In Fukushima nuclear reactor, the channel box was made of Zircaloy-4, and the control rode is made of B4C together with stainless steel cladding and sheath. In the study, the interaction among B4C, stainless steel (SUS), and Zircaloy-4 was investigated at 1473 K in either argon or air atmosphere. In argon, Zircaloy is melted by the diffusion of elements from SUS, and SUS was melted at 1473 K by the diffusion of C and B. In air, SUS reacted with B2O3 and formed an oxides melt firstly. Then, the oxidized Zircaloy contacted with this melt and fused. Moreover, the progress of core melting process during severe accident under different atmospheres was firstly discussed.

  10. Boron carbide (B4C) coating. Deposition and testing

    Science.gov (United States)

    Azizov, E.; Barsuk, V.; Begrambekov, L.; Buzhinsky, O.; Evsin, A.; Gordeev, A.; Grunin, A.; Klimov, N.; Kurnaev, V.; Mazul, I.; Otroshchenko, V.; Putric, A.; Sadovskiy, Ya.; Shigin, P.; Vergazov, S.; Zakharov, A.

    2015-08-01

    Boron carbide was proposed as a material of in-situ protecting coating for tungsten tiles of ITER divertor. To prove this concept the project including investigation of regimes of plasma deposition of B4C coating on tungsten and tests of boron carbide layer in ITER-like is started recently. The paper contends the first results of the project. The results of B4C coating irradiation by the plasma pulses of QSPU-T plasma accelerator are presented. The new device capable of B4C film deposition on tungsten and testing of the films and materials with ITER-like heat loads and ion- and electron irradiation is described. The results of B4C coating deposition and testing of both tungsten substrate and coating are shown and discussed.

  11. Characterization of LysB4, an endolysin from the Bacillus cereus-infecting bacteriophage B4

    Directory of Open Access Journals (Sweden)

    Son Bokyung

    2012-03-01

    Full Text Available Abstract Background Bacillus cereus is a foodborne pathogen that causes emetic or diarrheal types of food poisoning. The incidence of B. cereus food poisoning has been gradually increasing over the past few years, therefore, biocontrol agents effective against B. cereus need to be developed. Endolysins are phage-encoded bacterial peptidoglycan hydrolases and have received considerable attention as promising antibacterial agents. Results The endolysin from B. cereus phage B4, designated LysB4, was identified and characterized. In silico analysis revealed that this endolysin had the VanY domain at the N terminus as the catalytic domain, and the SH3_5 domain at the C terminus that appears to be the cell wall binding domain. Biochemical characterization of LysB4 enzymatic activity showed that it had optimal peptidoglycan hydrolase activity at pH 8.0-10.0 and 50°C. The lytic activity was dependent on divalent metal ions, especially Zn2+. The antimicrobial spectrum was relatively broad because LysB4 lysed Gram-positive bacteria such as B. cereus, Bacillus subtilis and Listeria monocytogenes and some Gram-negative bacteria when treated with EDTA. LC-MS analysis of the cell wall cleavage products showed that LysB4 was an L-alanoyl-D-glutamate endopeptidase, making LysB4 the first characterized endopeptidase of this type to target B. cereus. Conclusions LysB4 is believed to be the first reported L-alanoyl-D-glutamate endopeptidase from B. cereus-infecting bacteriophages. The properties of LysB4 showed that this endolysin has strong lytic activity against a broad range of pathogenic bacteria, which makes LysB4 a good candidate as a biocontrol agent against B. cereus and other pathogenic bacteria.

  12. General footage ISOLDE experimental hall

    CERN Multimedia

    2016-01-01

    Overview of the ISOLDE experimental hall. Equipment and experiments. Taken from the WITCH / EBIS platform: ISOLDE hall infrastructure, GHM line, LA1, LA2, LA0, central beamline, COLLAPS experiment, CRIS experiment, ISOLTRAP experiment, laser guidance from building 508 into the hall for laser spectroscopy COLLAPS and CRIS. Taken from the HIE ISOLDE shielding tunnel roof: ISOLDE hall infrastructure, WITCH experiment, VITO line, TAS experiment. General footage: High Tension room entrance and EBIS platform, staircases and passages in the experimental hall.

  13. Spontaneous Quantum Hall Liquids

    Science.gov (United States)

    Zhang, Fan

    2012-02-01

    Driven by electron-electron interactions, bilayer graphene and its thicker cousins, chirally (ABC) stacked multilayers, exhibit a variety of distinct broken symmetry states in which each spin-valley flavor spontaneously transfers charge between layers, because of their flat touching bands and large pseudospin chiralities. These gapped states are accompanied by large momentum space Berry curvatures and different types of topological orders. These competing ground states are distinguished by their flavor Hall conductivities, orbital magnetizations, edge state properties, and response to external fields. These spontaneous quantum Hall (SQH) states at zero field smoothly evolve into quantum Hall ferromagnet states at finite field. Various phase transitions occur by tuning carrier densities, temperature, and external fields. Recently, SQH states have started to be observed and explored in transport and Hall experiments on suspended devices with dual gates.

  14. Halls Lake 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Salt marsh habitats along the shoreline of Halls Lake are threatened by wave erosion, but the reconstruction of barrier islands to reduce this erosion will modify...

  15. Quantum Hall Effects

    OpenAIRE

    Goerbig, M. O.

    2009-01-01

    These lecture notes yield an introduction to quantum Hall effects both for non-relativistic electrons in conventional 2D electron gases (such as in semiconductor heterostructures) and relativistic electrons in graphene. After a brief historical overview in chapter 1, we discuss in detail the kinetic-energy quantisation of non-relativistic and the relativistic electrons in a strong magnetic field (chapter 2). Chapter 3 is devoted to the transport characteristics of the integer quantum Hall eff...

  16. The quantum hall effect

    International Nuclear Information System (INIS)

    Transport phenomena in two dimensional semiconductors have revealed unusual properties. In this thesis these systems are considered and discussed. The theories explain the Integral Quantum Hall Effect (IQHE) and the Fractional Quantum Hall Effect (FQHE). The thesis is composed of five chapters. The first and the second chapters lay down the theory of the IQHE, the third and fourth consider the theory of the FQHE. Chapter five deals with the statistics of particles in two dimension. (author). Refs

  17. Spin Hall Effect

    OpenAIRE

    Schliemann, John

    2006-01-01

    It is proposed that when a charge current circulates in a paramagnetic metal a transverse spin imbalance will be generated, giving rise to a 'spin Hall voltage'. Similarly, that when a spin current circulates a transverse charge imbalance will be generated, hence a Hall voltage, in the absence of charge current and magnetic field. Based on these principles we propose an experiment to generate and detect a spin current in a paramagnetic metal.

  18. Spin Hall noise

    OpenAIRE

    Kamra, A.; Witek, F.P.; Meyer, S.; Huebl, H.; Geprägs, S.; Gross, R.; Bauer, G. E. W.; Goennenwein, S. T. B.

    2014-01-01

    We measure the low-frequency thermal fluctuations of pure spin current in a Platinum film deposited on yttrium iron garnet via the inverse spin Hall effect (ISHE)-mediated voltage noise as a function of the angle $\\alpha$ between the magnetization and the transport direction. The results are consistent with the fluctuation dissipation theorem in terms of the recently discovered spin Hall magnetoresistance (SMR). We present a microscopic description of the $\\alpha$ dependence of the voltage no...

  19. Swimming hall water treatment

    OpenAIRE

    Valtonen, Jukka

    2015-01-01

    The purpose of this thesis was to see how ultraviolet light-treatment can improve water disinfection at Pori central swimming hall. The swimming hall has already an option for ultraviolet disinfection system, but there hasn’t been any immediate need for it to be utilized in combination with more conventional water treatment methods. Nevertheless, growing visitor numbers are already straining the swimming hall’s water treatment systems and some improvement was h...

  20. Experimental Hall design considerations

    International Nuclear Information System (INIS)

    General requirements for experimental halls at the Fermilab Collider are set forth, and specific designs for two halls are presented, one for the Detector Group's large ''W detector'' and the other for several smaller setups and for ep experiments. The physics which cannot be studied with the W detector is surveyed, and it is recommended that the second area incorporate a transposed geometry to allow small angle experiments. The most important recommendations are (1) that the halls have good access and the possibility of changing entire setups during short shutdowns, (2) that both equal energy (anti pp) and unequal energy (pp, ep) experiments be accommodated, (3) that construction take place during the superconducting ring installation, (4) that the halls incorporate assembly areas in which detectors can be built and serviced during machine operation and (5) that detailed design, including radiation safety calculations and muon background measurements, begin immediately. Some basic questions concerning the nature of the experimental halls needed for colliding beam experiments at Fermilab are discussed. General requirements and design considerations are dealt with first, followed by specific proposals for the layout of actual halls

  1. Validation testing of solute transport modelling using SHETRAN. The Calder Hollow experiments

    International Nuclear Information System (INIS)

    Hill-slope plot experiments were conducted at Calder Hollow, near Sellafield in West Cumbria, using lanthanum chloride (strongly sorbing) and strontium chloride (weakly sorbing) tracers in solution. Water and solute were injected via boreholes into a sand layer in a sequence of Quaternary drift deposits and the resulting subsurface transport plumes studied using core extraction and laboratory measurement of lanthanum, and fluid conductivity and bulk resistivity monitoring of strontium in an array of observation boreholes. Simulations of the field experiments were run using the SHETRAN hydrological modelling system. SHETRAN is a physically based, spatially distributed system. It was used to simulate the combined subsurface water flow (calibrated against field observations of piezometric head) and solute transport (uncalibrated, and run without any knowledge of the field observations for solute) taking place during the experiments. The results of the simulations were used to gauge the ability of SHETRAN to predict the subsurface transport of the lanthanum chloride and strontium chloride tracers in a validation exercise. The validation approach is based on the 'blind' method of Ewen and Parkin (1996), and involved using SHETRAN as it would be used in a real application. Ranges were established for the measured values of the physical properties of the porous media, supplemented by values from the literature, and these were used in conjunction with an analysis of calibrated flow simulations to create 48 SHETRAN parameter datasets for the lanthanum experiment and 16 for the strontium experiment. The datasets each led to a physically plausible simulation consistent with all the available information. A number of 'tests' were defined to compare model simulation results against field measurements. The simulations were used as a starting point to derive upper and lower 'bounds' for the model generated results, in order to incorporate uncertainty. Two teams produced distinct

  2. A calderón-preconditioned single source combined field integral equation for analyzing scattering from homogeneous penetrable objects

    KAUST Repository

    Valdés, Felipe

    2011-06-01

    A new regularized single source equation for analyzing scattering from homogeneous penetrable objects is presented. The proposed equation is a linear combination of a Calderón-preconditioned single source electric field integral equation and a single source magnetic field integral equation. The equation is immune to low-frequency and dense-mesh breakdown, and free from spurious resonances. Unlike dual source formulations, this equation involves operator products that cannot be discretized using standard procedures for discretizing standalone electric, magnetic, and combined field operators. Instead, the single source equation proposed here is discretized using a recently developed technique that achieves a well-conditioned mapping from div- to curl-conforming function spaces, thereby fully respecting the space mapping properties of the operators involved, and guaranteeing accuracy and stability. Numerical results show that the proposed equation and discretization technique give rise to rapidly convergent solutions. They also validate the equation\\'s resonant free character. © 2006 IEEE.

  3. B4C thin films for neutron detection

    International Nuclear Information System (INIS)

    Due to the very limited availability of 3He, new kinds of neutron detectors, not based on 3He, are urgently needed. Here, we present a method to produce thin films of 10B4C, with maximized detection efficiency, intended to be part of a new generation of large area neutron detectors. B4C thin films have been deposited onto Al-blade and Si wafer substrates by dc magnetron sputtering from natB4C and 10B4C targets in an Ar discharge, using an industrial deposition system. The films were characterized with scanning electron microscopy, elastic recoil detection analysis, x-ray reflectivity, and neutron radiography. We show that the film-substrate adhesion and film purity are improved by increased substrate temperature and deposition rate. A deposition rate of 3.8 A/s and substrate temperature of 400 deg. C result in films with a density close to bulk values and good adhesion to film thickness above 3 μm. Boron-10 contents of almost 80 at. % are obtained in 6.3 m2 of 1 μm thick 10B4C thin films coated on Al-blades. Initial neutron absorption measurements agree with Monte Carlo simulations and show that the layer thickness, number of layers, neutron wavelength, and amount of impurities are determining factors. The study also shows the importance of having uniform layer thicknesses over large areas, which for a full-scale detector could be in total ∼1000 m2 of two-side coated Al-blades with ∼1 μm thick 10B4C films.

  4. Conducting Wall Hall Thrusters

    Science.gov (United States)

    Goebel, Dan M.; Hofer, Richard R.; Mikellides, Ioannis G.; Katz, Ira; Polk, James E.; Dotson, Brandon

    2013-01-01

    A unique configuration of the magnetic field near the wall of Hall thrusters, called Magnetic Shielding, has recently demonstrated the ability to significantly reduce the erosion of the boron nitride (BN) walls and extend the life of Hall thrusters by orders of magnitude. The ability of magnetic shielding to minimize interactions between the plasma and the discharge chamber walls has for the first time enabled the replacement of insulating walls with conducting materials without loss in thruster performance. The boron nitride rings in the 6 kW H6 Hall thruster were replaced with graphite that self-biased to near the anode potential. The thruster efficiency remained over 60% (within two percent of the baseline BN configuration) with a small decrease in thrust and increase in Isp typical of magnetically shielded Hall thrusters. The graphite wall temperatures decreased significantly compared to both shielded and unshielded BN configurations, leading to the potential for higher power operation. Eliminating ceramic walls makes it simpler and less expensive to fabricate a thruster to survive launch loads, and the graphite discharge chamber radiates more efficiently which increases the power capability of the thruster compared to conventional Hall thruster designs.

  5. Nonlocal Anomalous Hall Effect

    Science.gov (United States)

    Zhang, Steven S.-L.; Vignale, Giovanni

    2016-04-01

    The anomalous Hall (AH) effect is deemed to be a unique transport property of ferromagnetic metals, caused by the concerted action of spin polarization and spin-orbit coupling. Nevertheless, recent experiments have shown that the effect also occurs in a nonmagnetic metal (Pt) in contact with a magnetic insulator [yttrium iron garnet (YIG)], even when precautions are taken to ensure that there is no induced magnetization in the metal. We propose a theory of this effect based on the combined action of spin-dependent scattering from the magnetic interface and the spin-Hall effect in the bulk of the metal. At variance with previous theories, we predict the effect to be of first order in the spin-orbit coupling, just as the conventional anomalous Hall effect—the only difference being the spatial separation of the spin-orbit interaction and the magnetization. For this reason we name this effect the nonlocal anomalous Hall effect and predict that its sign will be determined by the sign of the spin-Hall angle in the metal. The AH conductivity that we calculate from our theory is in order of magnitude agreement with the measured values in Pt /YIG structures.

  6. Nonlocal Anomalous Hall Effect.

    Science.gov (United States)

    Zhang, Steven S-L; Vignale, Giovanni

    2016-04-01

    The anomalous Hall (AH) effect is deemed to be a unique transport property of ferromagnetic metals, caused by the concerted action of spin polarization and spin-orbit coupling. Nevertheless, recent experiments have shown that the effect also occurs in a nonmagnetic metal (Pt) in contact with a magnetic insulator [yttrium iron garnet (YIG)], even when precautions are taken to ensure that there is no induced magnetization in the metal. We propose a theory of this effect based on the combined action of spin-dependent scattering from the magnetic interface and the spin-Hall effect in the bulk of the metal. At variance with previous theories, we predict the effect to be of first order in the spin-orbit coupling, just as the conventional anomalous Hall effect-the only difference being the spatial separation of the spin-orbit interaction and the magnetization. For this reason we name this effect the nonlocal anomalous Hall effect and predict that its sign will be determined by the sign of the spin-Hall angle in the metal. The AH conductivity that we calculate from our theory is in order of magnitude agreement with the measured values in Pt/YIG structures.

  7. Gas-flow detector for uranium contamination on finned-can surface of a reactor fuel

    International Nuclear Information System (INIS)

    This gas-flow detector is a gridded proportional-counter specially designed for detecting uranium contamination on the finned-can surface of a reactor fuel. A conventional proportional-counter constructed only by a cathode and collector can hardly detect alpha particles emitted from uranium which is contaminated on rugged surfaces such as those of the fins of a reactor-fuel can because of the lack of uniformity of the electric field near the surface. This is the reason why we have constructed the gridded proportional-counter. This counter comprises the fuel, a grid, collectors and a cathode which are cylindrical in construction and arranged coaxially. The fuel is placed in the centre of the grid and negative voltage is applied. The space between the fuel and the grid serves as an ion-collecting space. The grid is made of fine parallel tungsten wires which are constructed cylindrically around the fuel and connected to ground potential. The collectors are 16 fine tungsten wires constructed similarly to the grid, but each wire is electrically insulated from the others. Through 50-kΩ resistors all collectors are connected together and to positive high voltage via a feeding resistor. The space between the grid, the collectors and the cathode serves as a gas-multiplication space just like a conventional proportional-counter. Each 50-kΩ resistor separates the stray capacity of the connected collector from the others. The detector output is coupled with a low input-impedance-current amplifier. The low inputimpedance also lessens the bad influence of the stray capacity of the input circuitry. These result in a good S/N ratio and allow the sensitive detection of alpha particles. Before measurement, the counter is first evacuated by a rotary pump and then PR gas (A: 90%, Methane: 10%) is admitted. By the use of this new equipment we have successfully detected alpha particles emitted from 1 x 10-5 g natural-uranium contamination of the finned-can surface of a Calder Hall

  8. 26 CFR 1.410(b)-4 - Nondiscriminatory classification test.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.410(b)-4... employees who benefit under the plan. Reasonable classifications generally include specified job categories... paragraph (c)(4)(i) of this section. See § 1.410(b)-9 for the definition of a plan's ratio percentage....

  9. Hall Effect in a Plasma.

    Science.gov (United States)

    Kunkel, W. B.

    1981-01-01

    Describes an apparatus and procedure for conducting an undergraduate laboratory experiment to quantitatively study the Hall effect in a plasma. Includes background information on the Hall effect and rationale for conducting the experiment. (JN)

  10. The quantized Hall effect

    International Nuclear Information System (INIS)

    The quantized Hall effect is theoretically explained in detail as are its basic properties. The explanation is completed with the pertinent mathematical relations and illustrative figures. Experimental data are critically assessed obtained by quantum transport measurement in a magnetic field on two-dimensional systems. The results are reported for a MOSFET silicon transistor and for GaAs-AlxGa1-xAs heterostructures. The application is discussed of the quantized Hall effect in determining the fine structure constant or in implementing the resistance standard. (M.D.). 27 figs., 57 refs

  11. Hall Effect in Quasicrystals

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xiang; HU Cheng-zheng; GONG Ping; WANG Ai-jun

    2005-01-01

    The relations between Hall effect and symmetry are discussed for all 2- and 3 dimensional quasicrystals with crystallographically forbidden symmetries. The results show that the numbers of independent components of the Hall coefficient (RH) are one for 3-dimensional quasicrystals, two for those 2 dimensional quasicrystals whose symmetry group is non-Abelian, and three for those 2-dimensional quasicrystals whose symmetry group is Abelian, respectively. The quasicrystals with the same number of independent components have the same form of the components of RH.

  12. Model anisotropic quantum Hall states

    OpenAIRE

    Qiu, R. -Z.; Haldane, F.D.M.; Wan, Xin; Yang, Kun; Yi, Su

    2012-01-01

    Model quantum Hall states including Laughlin, Moore-Read and Read-Rezayi states are generalized into appropriate anisotropic form. The generalized states are exact zero-energy eigenstates of corresponding anisotropic two- or multi-body Hamiltonians, and explicitly illustrate the existence of geometric degrees of in the fractional quantum Hall effect. These generalized model quantum Hall states can provide a good description of the quantum Hall system with anisotropic interactions. Some numeri...

  13. The quantum anomalous Hall effect

    OpenAIRE

    LIU, CHAO-XING; Zhang, Shou-Cheng; Qi, Xiao-Liang

    2015-01-01

    The quantum anomalous Hall effect is defined as a quantized Hall effect realized in a system without external magnetic field. Quantum anomalous Hall effect is a novel manifestation of topological structure in many-electron systems, and may have potential applications in future electronic devices. In recent years, quantum anomalous Hall effect has been proposed theoretically and realized experimentally. In this review article, we provide a systematic overview of the theoretical and experimenta...

  14. The Fractional Quantum Hall Effect

    OpenAIRE

    Rao, Sumathi

    1999-01-01

    We give a brief introduction to the phenomenon of the Fractional Quantum Hall effect, whose discovery was awarded the Nobel prize in 1998. We also explain the composite fermion picture which describes the fractional quantum Hall effect as the integer quantum Hall effect of composite fermions.

  15. "Calderón en el Romea", taller interdisciplinar para Educación Secundaria: la experiencia pedagógica

    OpenAIRE

    Caro Valverde, María Teresa; Gea Martínez, Fernando; Sánchez Mateos, Ana Rosa

    2008-01-01

    Trabajo descriptivo y reflexivo del proceso didáctico interdisciplinar y del valor pedagógico humanista de la experiencia de innovación educativa que dio lugar a la publicación "Calderón en el Romea", obra que recibió varios premios nacionales por parte de Santillana, y de la que fueron coordinadores los autores de este documento.

  16. Hall Sweet Home

    Science.gov (United States)

    Oguntoyinbo, Lekan

    2011-01-01

    Many urban and commuter universities have their sights set on students who are unlikely to connect with the college and likely to fail unless the right strategies are put in place to help them graduate. In efforts to improve retention rates, commuter colleges are looking to an unusual suspect: residence halls. The author discusses how these…

  17. Spin Hall noise

    NARCIS (Netherlands)

    Kamra, A.; Witek, F.P.; Meyer, S.; Huebl, H.; Geprägs, S.; Gross, R.; Bauer, G.E.W.; Goennenwein, S.T.B.

    2014-01-01

    We measure the low-frequency thermal fluctuations of pure spin current in a platinum film deposited on yttrium iron garnet via the inverse spin Hall effect (ISHE)-mediated voltage noise as a function of the angle α between the magnetization and the transport direction. The results are consistent wit

  18. The Monty Hall Dilemma

    NARCIS (Netherlands)

    Barteld Kooi, [No Value

    2006-01-01

    Samenvatting: In het begin van de jaren negentig brak een wereldwijde discussie los over een probleem dat in het Engels 'The Monty Hall Dilemma' wordt genoemd. Marilyn vos Savant, die in het Guinness Book of World Records wordt genoemd als degene met het

  19. Relativistic Hall Effect

    CERN Document Server

    Bliokh, Konstantin Y

    2011-01-01

    We consider the relativistic deformation of quantum waves and mechanical bodies carrying intrinsic angular momentum (AM). When observed in a moving reference frame, the centroid of the object undergoes an AM-dependent transverse shift. This is the relativistic analogue of the spin Hall effect, which occurs in free space without any external fields. Remarkably, the shifts of the geometric and energy centroids differ by a factor of 2, and both centroids are crucial for the correct Lorentz transformations of the AM tensor. We examine manifestations of the relativistic Hall effect in quantum vortices, mechanical flywheel, and discuss various fundamental aspects of the phenomenon. The perfect agreement of quantum and relativistic approaches allows applications at strikingly different scales: from elementary spinning particles, through classical light, to rotating black-holes.

  20. Cylindrical geometry hall thruster

    Science.gov (United States)

    Raitses, Yevgeny; Fisch, Nathaniel J.

    2002-01-01

    An apparatus and method for thrusting plasma, utilizing a Hall thruster with a cylindrical geometry, wherein ions are accelerated in substantially the axial direction. The apparatus is suitable for operation at low power. It employs small size thruster components, including a ceramic channel, with the center pole piece of the conventional annular design thruster eliminated or greatly reduced. Efficient operation is accomplished through magnetic fields with a substantial radial component. The propellant gas is ionized at an optimal location in the thruster. A further improvement is accomplished by segmented electrodes, which produce localized voltage drops within the thruster at optimally prescribed locations. The apparatus differs from a conventional Hall thruster, which has an annular geometry, not well suited to scaling to small size, because the small size for an annular design has a great deal of surface area relative to the volume.

  1. CALDER - Neutrinoless double-beta decay identification in TeO$_2$ bolometers with kinetic inductance detectors

    CERN Document Server

    Battistelli, E S; Calvo, M; Cardani, L; Casali, N; Castellano, M G; Colantoni, I; Coppolecchia, A; Cosmelli, C; Cruciani, A; de Bernardis, P; Di Domizio, S; D'Addabbo, A; Martinez, M; Masi, S; Pagnanini, L; Tomei, C; Vignati, M

    2015-01-01

    Next-generation experiments searching for neutrinoless double-beta decay must be sensitive to a Majorana neutrino mass as low as 10 meV. CUORE, an array of 988 TeO$_2$ bolometers being commissioned at Laboratori Nazionali del Gran Sasso in Italy, features an expected sensitivity of 50-130 meV at 90% C.L, that can be improved by removing the background from $\\alpha$ radioactivity. This is possible if, in coincidence with the heat release in a bolometer, the Cherenkov light emitted by the $\\beta$ signal is detected. The amount of light detected is so far limited to only 100 eV, requiring low-noise cryogenic light detectors. The CALDER project (Cryogenic wide-Area Light Detectors with Excellent Resolution) aims at developing a small prototype experiment consisting of TeO$_2$ bolometers coupled to new light detectors based on kinetic inductance detectors. The R&D is focused on the light detectors that could be implemented in a next-generation neutrinoless double-beta decay experiment.

  2. CALDER - Neutrinoless double-beta decay identification in TeO2 bolometers with kinetic inductance detectors

    Science.gov (United States)

    Vignati, M.; Bellini, F.; Cardani, L.; Casali, N.; Castellano, M. G.; Colantoni, I.; Coppolecchia, A.; Cosmelli, C.; Cruciani, A.; D’Addabbo, A.; Di Domizio, S.; Martinez, M.; Tomei, C.

    2016-05-01

    Next-generation experiments searching for neutrinoless double-beta decay must be sensitive to a Majorana neutrino mass as low as 10 meV. CUORE, an array of 988 TeO2 bolometers being commissioned at Laboratori Nazionali del Gran Sasso in Italy, features an expected sensitivity of 50-130 meV at 90% C.L, that can be improved by removing the background from α radioactivity. This is possible if, in coincidence with the heat release in a bolometer, the Cherenkov light emitted by the β signal is detected. The amount of light detected is so far limited to only 100 eV, requiring low-noise cryogenic light detectors. The CALDER project (Cryogenic wide-Area Light Detectors with Excellent Resolution) aims at developing a small prototype experiment consisting of TeO2 bolometers coupled to new light detectors based on kinetic inductance detectors. The present R&D is focused on the light detectors. We present the latest results and the perspectives of the project.

  3. Weak And Strong Type Estimates for Maximal Truncations of Calder\\'on-Zygmund Operators on $ A_p$ Weighted Spaces

    CERN Document Server

    Hytönen, Tuomas P; Martikainen, Henri; Orponen, Tuomas; Reguera, Maria Carmen; Sawyer, Eric T; Uriarte-Tuero, Ignacio

    2011-01-01

    For 1Calder\\'on-Zygmund operator T, we show that there is a constant C(T,P) so that we prove the sharp norm dependence on T_#, the maximal truncations of T, in both weak and strong type L^p(w) norms. Namely, for the weak type norm, T_# maps L^p(w) to weak-L^p(w) with norm at most \\|w\\|_{A_p}. And for the strong type norm, the norm estimate is \\|w\\|_{A_p}^{\\max(1, (p-1) ^{-1})}. These estimates are not improvable in the power of \\lVert w\\rVert_{A_p}. Our argument follows the outlines of the arguments of Lacey-Petermichl-Reguera (Math.\\ Ann.\\ 2010) and Hyt\\"onen-P\\'erez-Treil-Volberg (arXiv, 2010) with new ingredients, including a weak-type estimate for certain duals of T_#, and sufficient conditions for two weight inequalities in L ^{p} for T_#. Our proof does not rely upon extrapolation.

  4. Normal Modes of the B=4 Skyrme Soliton

    CERN Document Server

    Barnes, C; Turok, N G; Barnes, Chris; Baskerville, Kim; Turok, Neil

    1997-01-01

    The Skyrme model of nuclear physics requires quantisation if it is to match observed nuclear properties. A simple technique is used to find the normal mode spectrum of the baryon number $B=4$ Skyrme soliton, representing the $\\alpha$ particle. We find sixteen vibrational modes and classify them under the cubic symmetry group $O_h$ of the static solution. The spectrum possesses a remarkable structure, with the lowest energy modes lying in those representations expected from an approximate correspondence between Skyrmions and BPS monopoles. The next mode up is the `breather', and above that are higher multipole breathing modes.

  5. Hall Drag in Correlated Double Layer Quantum Hall Systems

    OpenAIRE

    Yang, Kun

    1998-01-01

    We show that in the limit of zero temperature, double layer quantum Hall systems exhibit a novel phenomena called Hall drag, namely a current driven in one layer induces a voltage drop in the other layer, in the direction perpendicular to the driving current. The two-by-two Hall resistivity tensor is quantized and proportional to the ${\\bf K}$ matrix that describes the topological order of the quantum Hall state, even when the ${\\bf K}$ matrix contains a zero eigenvalue, in which case the Hal...

  6. Neutron irradiation tests on B4C/epoxy composite for neutron shielding application and the parameters assay

    Science.gov (United States)

    Adeli, Ruhollah; Shirmardi, Seyed Pezhman; Ahmadi, Seyed Javad

    2016-10-01

    In this investigation, epoxy resin with a low viscosity amine-based curing agent was chosen as matrix and additives were added to epoxy resin using low speed stirring with ultrasonic waves approach. The chemical stability of resin during fabrication of composites was studied with Fourier transform infrared spectroscopy (FTIR). The effect of B4C particle size (20 and 150 μm) on neutron shielding was investigated. Besides, in order to develop the high performance composites, the effect of ATH (flame retardant) and WO3 powders (for shielding from against gamma rays) on neutron shielding property is considered. The neutron experiments were based on foil activation analysis in thermal column of Tehran Research Reactor (TRR). According to experimental data, required shield thickness (B4C, 150 μm, 3 wt%) for 80% absorption of neutron fluence was calculated about 9.8 mm. Consequently, data show thermal neutron absorption is dependent also on the size of the boron compound filler and show a significant enhancement in shielding performance when using smaller particle size of B4C filler. Furthermore, data obviously show that the neutron attenuation coefficient of reinforced composites increases to 0.345 cm-1 for B4C (20 μm, 5 wt%)/ Epoxy composite shield. As clearly data indicate, adding WO3 and ATH additive had a significant influence on the thermal neutron attenuation property and hybrid shield shows an enhancement of more than 60% in shielding performance.

  7. Magnesium Hall Thruster

    Science.gov (United States)

    Szabo, James J.

    2015-01-01

    This Phase II project is developing a magnesium (Mg) Hall effect thruster system that would open the door for in situ resource utilization (ISRU)-based solar system exploration. Magnesium is light and easy to ionize. For a Mars- Earth transfer, the propellant mass savings with respect to a xenon Hall effect thruster (HET) system are enormous. Magnesium also can be combusted in a rocket with carbon dioxide (CO2) or water (H2O), enabling a multimode propulsion system with propellant sharing and ISRU. In the near term, CO2 and H2O would be collected in situ on Mars or the moon. In the far term, Mg itself would be collected from Martian and lunar regolith. In Phase I, an integrated, medium-power (1- to 3-kW) Mg HET system was developed and tested. Controlled, steady operation at constant voltage and power was demonstrated. Preliminary measurements indicate a specific impulse (Isp) greater than 4,000 s was achieved at a discharge potential of 400 V. The feasibility of delivering fluidized Mg powder to a medium- or high-power thruster also was demonstrated. Phase II of the project evaluated the performance of an integrated, highpower Mg Hall thruster system in a relevant space environment. Researchers improved the medium power thruster system and characterized it in detail. Researchers also designed and built a high-power (8- to 20-kW) Mg HET. A fluidized powder feed system supporting the high-power thruster was built and delivered to Busek Company, Inc.

  8. Irradiation tests of ITER candidate Hall sensors using two types of neutron spectra.

    Science.gov (United States)

    Ďuran, I; Bolshakova, I; Viererbl, L; Sentkerestiová, J; Holyaka, R; Lahodová, Z; Bém, P

    2010-10-01

    We report on irradiation tests of InSb based Hall sensors at two irradiation facilities with two distinct types of neutron spectra. One was a fission reactor neutron spectrum with a significant presence of thermal neutrons, while another one was purely fast neutron field. Total neutron fluence of the order of 10(16) cm(-2) was accumulated in both cases, leading to significant drop of Hall sensor sensitivity in case of fission reactor spectrum, while stable performance was observed at purely fast neutron spectrum. This finding suggests that performance of this particular type of Hall sensors is governed dominantly by transmutation. Additionally, it further stresses the need to test ITER candidate Hall sensors under neutron flux with ITER relevant spectrum.

  9. Irradiation tests of ITER candidate Hall sensors using two types of neutron spectra

    International Nuclear Information System (INIS)

    We report on irradiation tests of InSb based Hall sensors at two irradiation facilities with two distinct types of neutron spectra. One was a fission reactor neutron spectrum with a significant presence of thermal neutrons, while another one was purely fast neutron field. Total neutron fluence of the order of 1016 cm-2 was accumulated in both cases, leading to significant drop of Hall sensor sensitivity in case of fission reactor spectrum, while stable performance was observed at purely fast neutron spectrum. This finding suggests that performance of this particular type of Hall sensors is governed dominantly by transmutation. Additionally, it further stresses the need to test ITER candidate Hall sensors under neutron flux with ITER relevant spectrum.

  10. Topological Orbital Angular Momentum Hall Current

    OpenAIRE

    Hu, Jiangping

    2005-01-01

    We show that there is a fundamental difference between spin Hall current and orbital angular momentum Hall current in Rashba- Dresselhaus spin orbit coupling systems. The orbital angular momentum Hall current has a pure topological contribution which is originated from the existence of magnetic flux in momentum space while there is no such topological nature for the spin Hall current. Moreover, we show that the orbital Hall conductance is always larger than the spin Hall conductance in the pr...

  11. La identidad nacional y Calderón en la polémica teatral de 1762-1764

    Directory of Open Access Journals (Sweden)

    Bezhanova, Olga

    2004-06-01

    Full Text Available Drawing on contemporary theories about national identity, legitimacy and intellectual authority this article explores identitarian issues at stake during the 1762-1764 controversy on Spanish theater. Re-reading texts by Clavijo y Fajardo (El Pensador, Nicolás Fernández de Moratín (Desengaños al teatro español and other writings, Mariano José Nipho (Diario Estrangero and La nación española defendida and José Romea y Tapia (El escritor sin título we contend that what these authors are debating indeed is not theater but the legitimacy and authority they are claiming for, and ultimately opposing conceptions of national identity. Calderón becoming a cultural icon of such identity. Particularly significant is the role of autos sacramentales in this context. In effect, acrimony and irritation are part of this polemics because orthodox Catholicism is, from a conservative point of view, an essential component of what they consider Spanish national identity. The prohibition of the autos is just a sign of a temporary change in the relationship of forces.A partir de teorías actuales sobre la identidad nacional, la legitimidad y la autoridad intelectual, este artículo explora los puntos clave identitarios que se ponen en juego durante la polémica sobre el teatro español de los años 1762-1764. Mediante una re-lectura de los textos de Clavijo y Fajardo (El Pensador, Nicolás Fernández de Moratín (Desengaños al teatro español y otros escritos, Mariano José Nipho (Diario Estrangero y La nación española defendida y José Romea y Tapia (El escritor sin título, sostenemos que lo que estos autores discuten realmente no es sobre el teatro, sino sobre la legitimidad y autoridad que reclaman, y en último término concepciones enfrentadas sobre la identidad nacional, de la que Calderón parece convertirse en icono cultural. De particular significación es el papel de los autos sacramentales en este contexto. En efecto, la acritud y la irritaci

  12. Pericarditis y Pericardiectomía: Experiencia en el Hospital R. A. Calderón Guardia, 2003-2010

    Directory of Open Access Journals (Sweden)

    Eric Rubí Chacón

    2011-12-01

    Full Text Available Introducción. La pericarditis puede presentarse como un derrame pericárdico o como constricción pericárdica y en un pequeño porcentaje de pacientes, ocurren ambos. Las causas son variadas y en ocasiones, la resolución es quirúrgica. El propósito de este reporte es mostrar la experiencia quirúrgica acumulada en nuestro centro durante los últimos 7 años. Métodos. Se revisaron los expedientes clínicos de todos los pacientes a quienes se les practicó una intervención pericárdica primaria por derrame pericárdico o pericarditis constrictiva en el Hospital Rafael A. Calderón Guardia en San José, Costa Rica, desde octubre de 2003 a setiembre de 2010. Se excluyeron aquellos individuos con derrame pericárdico secundario a sobreanticoagulación, cirugía cardiaca reciente, trauma torácico o trasudados secundarios a patología sistémica. Resultados. Se incluyeron 19 pacientes, 11 hombres y 8 mujeres, 16 con derrame pericárdico y 3 con pericarditis constrictiva. Treinta y siete por ciento de los pacientes tuvieron cuadros de pericarditis inespecífica, 32% tenían una pericarditis infecciosa, y 26% tuvieron pericarditis de origen neoplásico, 1 tuvo una pericarditis quilosa. Tres enfermos eran portadores de virus de inmunodeficiencia humana, 2 con pericarditis tuberculosa y 1 con pericarditis inespecífica. En general los pacientes con derrame hemodinámicamente importante fueron abordados mediante ventana subxifoidea y en los casos de constricción se utilizó pericardiectomía. Solo un paciente falleció en esta serie, por síndrome de bajo gasto postoperatorio. Conclusión. Se revisa el manejo clínico, quirúrgico y anestésico de estos enfermos y se analiza el síndrome de bajo gasto, que puede ocurrir en algunos de ellos al drenar el líquido o al descomprimir el corazónIntroduction. Pericarditis may present with a pericardial effusion of variable size, inflammation alone or constrictive pericarditis. In a small percentage of

  13. Hall Effect in spinor condensates

    OpenAIRE

    Taillefumier, Mathieu; Dahl, Eskil K.; Brataas, Arne; Hofstetter, Walter

    2009-01-01

    We consider a neutral spinor condensate moving in a periodic magnetic field. The spatially dependent magnetic field induces an effective spin dependent Lorentz force which in turn gives rise to a spin dependent Hall effect. Simulations of the Gross-Pitaevskii equation quantify the Hall effect. We discuss possible experimental realizations.

  14. Residence Hall Seating That Works.

    Science.gov (United States)

    Wiens, Janet

    2003-01-01

    Describes the seating chosen for residence halls at the Massachusetts Institute of Technology and the University of New England. The seating required depends on ergonomics, aesthetics, durability, cost, and code requirements. In addition, residence halls must have a range of seating types to accommodate various uses. (SLD)

  15. NPS Alumni Hall of Fame

    OpenAIRE

    2013-01-01

    Lists NPS Alumni Hall of Fame awardees. "The NPS Hall of Fame recognizes the accomplishments of NPS's most distinguished alumni and friends who, through the attainment of positions at the highest levels of public service, have made the greatest contributions to society, their nations and to the Naval Postgraduate School. "

  16. Funciones del sueño en un auto de Calderón: Sueños hay que verdad son (1670)

    OpenAIRE

    Gilbert, Françoise

    2005-01-01

    International audience SUMMARY:This study seeks to analyze the different functions of dream in the auto of Calderón, Sueños hay que verdad son (1670), which is based on some episodes from Josef's life in Genesis. Beginning with the structuring function of dream, in Bible stories, I study the dramatic function of this motif in this auto, within the sacramental frame of a double reading: historial and allegorical. After first establishing the structure of the work based on its metrical organ...

  17. High-order Div- and Quasi Curl-Conforming Basis Functions for Calderón Multiplicative Preconditioning of the EFIE

    KAUST Repository

    Valdes, Felipe

    2011-04-01

    A new high-order Calderón multiplicative preconditioner (HO-CMP) for the electric field integral equation (EFIE) is presented. In contrast to previous CMPs, the proposed preconditioner allows for high-order surface representations and current expansions by using a novel set of high-order quasi curl-conforming basis functions. Like its predecessors, the HO-CMP can be seamlessly integrated into existing EFIE codes. Numerical results demonstrate that the linear systems of equations obtained using the proposed HO-CMP converge rapidly, regardless of the mesh density and of the order of the current expansion. © 2006 IEEE.

  18. The ISOLDE hall

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Since 1992, after its move from the 600 MeV SC, ISOLDE is a customer of the Booster (then 1 GeV, now 1.4 GeV). The intense Booster beam (some 3E13 protons per pulse) is directed onto a target, from which a mixture of isotopes emanates. After ionization and electrostatic acceleration to 60 keV, they enter one of the 2 spectrometers (General Purpose Separator: GPS, and High Resolution Separator: HRS) from which the selected ions are directed to the experiments. The photos show: the REX-ISOLDE post accelerator; the mini-ball experiment; an overview of the ISOLDE hall. In the picture (_12) of the hall, the separators are behind the wall. From either of them, beams can be directed into any of the many beamlines towards the experiments, some of which are visible in the foreground. The elevated cubicle at the left is EBIS (Electron Beam Ion Source), which acts as a charge-state multiplier for the REX facility. The ions are further mass analzyzed and passed on to the linac which accelerates them to higher energies. T...

  19. Effect of the Ti/B4C mole ratio on the reaction products and reaction mechanism in an Al–Ti–B4C powder mixture

    International Nuclear Information System (INIS)

    The effect of the Ti/B4C mole ratio on the fabrication behavior of Al composites is investigated using Al–Ti–B4C powder mixtures as reactants. The quick spontaneous infiltration (QSI) process combined with the combustion reaction and DTA analysis were used. According to the thermodynamic predictions, which are verified in the experimental results, TiB2 is formed in all the samples whereas TiC is only formed in reactants with a Ti/B4C mole ratio of more than two. The C atoms from the reacted B4C do not move into TiC but instead they move into Al3BC or Al4C3 when the Ti/B4C mole ratio is less than two. In addition, the reaction mechanism with a Ti/B4C mole ratio of 0.75 is investigated extensively. - Highlights: • The critical role of the Ti/B4C mole ratio on the reaction products of Al–Ti–B4C was studied using experiments. • The experimental results are also supported by thermodynamic calculations presented in this paper. • The reaction mechanism with a Ti/B4C mole ratio of 0.75 is investigated extensively

  20. X-ray properties and interface study of B4C/Mo and B4C/Mo2C periodic multilayers

    Science.gov (United States)

    Choueikani, F.; Bridou, F.; Lagarde, B.; Meltchakov, E.; Polack, F.; Mercere, P.; Delmotte, F.

    2013-04-01

    We present a comparative study of B4C/Mo and B4C/Mo2C periodic multilayer structures deposited by magnetron sputtering. The characterization was performed by grazing incidence X-ray reflectometry at two different energies and high resolution transmission electron microscopy. The experimental results indicate the existence of an interdiffusion layer at the B4C-on-Mo interface in the B4C/Mo system. Thus, the B4C/Mo multilayers were modeled by an asymmetric structure with three layers in each period. The thickness of B4C-on-Mo interfacial layer was estimated about 1.1 nm. The B4C/Mo2C multilayers present less interdiffusion and are well modeled by a symmetric structure without interfacial layers. This study shows that B4C/Mo2C structure is an interesting alternative to B4C/Mo multilayer for X-ray optic applications.

  1. Farm Hall: The Play

    Science.gov (United States)

    Cassidy, David C.

    2013-03-01

    It's July 1945. Germany is in defeat and the atomic bombs are on their way to Japan. Under the direction of Samuel Goudsmit, the Allies are holding some of the top German nuclear scientists-among them Heisenberg, Hahn, and Gerlach-captive in Farm Hall, an English country manor near Cambridge, England. As secret microphones record their conversations, the scientists are unaware of why they are being held or for how long. Thinking themselves far ahead of the Allies, how will they react to the news of the atomic bombs? How will these famous scientists explain to themselves and to the world their failure to achieve even a chain reaction? How will they come to terms with the horror of the Third Reich, their work for such a regime, and their behavior during that period? This one-act play is based upon the transcripts of their conversations as well as the author's historical work on the subject.

  2. Descripción y análisis de capas superpuestas en El castillo de Lindabridis de Calderón

    Directory of Open Access Journals (Sweden)

    Escudero Baztán, Juan Manuel

    2015-06-01

    Full Text Available This paper describes and analyzes the highlights of a play El castillo de Lindabridis of Calderón de la Barca: topics relating to the date of his writing and his performances in the seventeenth century, the management of chivalric sources, the unitary structure, the use of emblematic material through the medieval bestiaries, musical interludes, and the staging and the repetition of themes and motifs, along with some final considerations about gender. All these factors indicate the particular importance of this comedy of Calderón.Este trabajo describe y analiza los puntos más relevantes de una obra caballeresca calderoniana poco conocida como El castillo de Lindabridis: cuestiones relativas a la fecha de su escritura y sus representaciones en el siglo XVII, al manejo de las fuentes caballerescas, a la estructura unitaria, al uso de la emblemática a través de los bestiarios medievales, a los interludios musicales, a la escenificación y la repetición de temas y motivos, junto a unas consideraciones finales sobre el género. Elementos en su conjunto que indican la particular relevancia de esta comedia de gran espectáculo calderoniana.

  3. City and Town Halls; townHalls13

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — Locations of city and town halls in Rhode Island. Derived using information originally compiled by the State of Rhode Island (http://www.ri.gov), and built upon...

  4. Tuning giant anomalous Hall resistance ratio in perpendicular Hall balance

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J. Y.; Yang, G. [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang, S. G., E-mail: sgwang@iphy.ac.cn, E-mail: ghyu@mater.ustb.edu.cn [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Liu, J. L. [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Wang, R. M. [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Amsellem, E.; Kohn, A. [Department of Materials Engineering, Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Yu, G. H., E-mail: sgwang@iphy.ac.cn, E-mail: ghyu@mater.ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-04-13

    Anomalous Hall effect at room temperature in perpendicular Hall balance with a core structure of [Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4} has been tuned by functional CoO layers, where [Pt/Co]{sub 4} multilayers exhibit perpendicular magnetic anisotropy. A giant Hall resistance ratio up to 69 900% and saturation Hall resistance (R{sub S}{sup P}) up to 2590 mΩ were obtained in CoO/[Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4}/CoO system, which is 302% and 146% larger than that in the structure without CoO layers, respectively. Transmission electron microscopy shows highly textured [Co/Pt]{sub 4} multilayers and oxide layers with local epitaxial relations, indicating that the crystallographic structure has significant influence on spin dependent transport properties.

  5. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  6. Multilayer thin film Hall effect device

    Science.gov (United States)

    Peters, Palmer N. (Inventor); Sisk, R. Charles (Inventor)

    1994-01-01

    A Hall effect device and a method of obtaining a magnetic field map of a magnetic body with the Hall effect device are presented. The device comprises: (1) a substrate, (2) a first layer having a first Hall coefficient deposited over the substrate, and (3) a second layer having a second Hall coefficient deposited over the first layer, the first and second layers cooperating to create, in the Hall effect device, a third Hall coefficient different from the first and second Hall coefficients. Creation of the third Hall coefficient by cooperation of the first and second layers allows use of materials for the first and second layers that were previously unavailable for Hall effect devices due to their relatively weak Hall coefficient.

  7. 26 CFR 1.475(b)-4 - Exemptions-transitional issues.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Exemptions-transitional issues. 1.475(b)-4 Section 1.475(b)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Inventories § 1.475(b)-4 Exemptions—transitional issues....

  8. 26 CFR 48.4161(b)-4 - Tax-free sales.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Tax-free sales. 48.4161(b)-4 Section 48.4161(b)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) MISCELLANEOUS EXCISE TAXES MANUFACTURERS AND RETAILERS EXCISE TAXES Sporting Goods § 48.4161(b)-4 Tax-free sales....

  9. General footage ISOLDE experimental hall HD

    CERN Multimedia

    2016-01-01

    Overview of the ISOLDE experimental hall. Equipment and experiments. Taken from the WITCH / EBIS platform: ISOLDE hall infrastructure, GHM line, LA1, LA2, LA0, central beamline, COLLAPS experiment, CRIS experiment, ISOLTRAP experiment, laser guidance from building 508 into the hall for laser spectroscopy COLLAPS and CRIS. Taken from the HIE ISOLDE shielding tunnel roof: ISOLDE hall infrastructure, WITCH experiment, VITO line, TAS experiment. General footage: High Tension room entrance and EBIS platform, staircases and passages in the experimental hall.

  10. Shared Magnetics Hall Thruster Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the proposed Phase I program, Busek Co. will demonstrate an innovative methodology for clustering Hall thrusters into a high performance, very high power...

  11. Shared Magnetics Hall Thruster Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the proposed Phase II program, Busek Co. will demonstrate an innovative methodology for clustering Hall thrusters into a high performance, very high power...

  12. "Hall mees" Linnateatris / Triin Sinissaar

    Index Scriptorium Estoniae

    Sinissaar, Triin

    1999-01-01

    Tallinn Linnateatri ja Raadioteatri ühislavastus "Hall mees" Gill Adamsi näidendi järgi, lavastaja Eero Spriit, osades Helene Vannari ja Väino Laes, kunstnik Kustav - Agu Püüman. Esietendus 22. okt

  13. Theory of spin Hall effect

    OpenAIRE

    Chudnovsky, Eugene M.

    2007-01-01

    An extension of Drude model is proposed that accounts for spin and spin-orbit interaction of charge carriers. Spin currents appear due to combined action of the external electric field, crystal field and scattering of charge carriers. The expression for spin Hall conductivity is derived for metals and semiconductors that is independent of the scattering mechanism. In cubic metals, spin Hall conductivity $\\sigma_s$ and charge conductivity $\\sigma_c$ are related through $\\sigma_s = [2 \\pi \\hbar...

  14. Duality Near Quantum Hall Transitions

    OpenAIRE

    Shimshoni, E.; Sondhi, S. L.; Shahar, D.

    1996-01-01

    A recent experiment by Shahar et al, on the phase transitions between quantum Hall states and the insulator, found that the current-voltage characteristics in the two phases are related by symmetry. It was suggested in this work that this is evidence for charge-flux duality near quantum Hall transitions. Here we provide details of this analysis. (Appearances notwithstanding, this is a theoretical paper.)

  15. Multiprobe quantum spin Hall bars

    OpenAIRE

    Sanvito, Stefano

    2013-01-01

    PUBLISHED We analyze electron transport in multiprobe quantum spin Hall (QSH) bars using the B¨uttiker formalism and draw parallels with their quantum Hall (QH) counterparts. We find that in a QSH bar the measured resistance changes upon introducing side voltage probes, in contrast to the QH case. We also study four- and six-terminal geometries and derive the expressions for the resistances. For these our analysis is generalized from the single-channel to the multi-channel case...

  16. High Heat Flux Testing of B4C/Cu and SiC/Cu Functionally Graded Materials Simulated by Laser and Electron Beam

    Institute of Scientific and Technical Information of China (English)

    刘翔; 谌继明; 张斧; 许增裕; 葛昌纯; 李江涛

    2002-01-01

    B4C, SiC and C, Cu functionally graded-materials (FGMs) have been developed by plasma spraying and hot pressing. Their high-heat flux properties have been investigated by high energy laser and electron beam for the simulation of plasma disruption process of the future fusion reactors, And a study on eroded products of B4C/Cu FGM under transient thermal load of electron beam was performed. In the experiment, SEM and EDS analysis indicated that B4C and SiC were decomposed, carbon was preferentially evaporated under high thermal load, and a part of Si and Cu were melted, in addition, the splash of melted metal and the particle emission of brittle destruction were also found. Different erosive behaviors of carbon-based materials (CBMs) caused by laser and electron beam were also discussed.

  17. The Effect of Calcination Temperature on Synthesis of B4C-Nano Tib2 Composite by Co-Precipitation Method

    Directory of Open Access Journals (Sweden)

    Saeid Abedini Khorrami

    2016-08-01

    Full Text Available Titanium diboride is one of the candidate materials for high temperature applications and also for control rod elements in high temperature reactors. This paper presents the experimental data on the composites of B4C-nano TiB2 that were synthesized successfully by co-precipitation method at temperatures between 973 and 1523K. Titanium tetraisopropoxide, boron carbide and isopropanol were used as the precursor materials. The phase constitution and microstructure of B4C-nano TiB2 during synthesis were investigated. X-ray diffraction (XRD and scanning electron microscopy (SEM were used to determine phase and microstructure of TiB2-B4C composites. The DTA/DDTA and TG/DTG results improve that the first exothermic reaction is TiO2 phase and second exothermic reaction takes place at 1523K which is TiB2 phase

  18. High heat flux testing of B4C/Cu and SiC/Cu functionally graded materials simulated by laser and electron beam

    International Nuclear Information System (INIS)

    B4C, SiC and C, Cu functionally graded-materials (FGMs) have been developed by plasma spraying and hot pressing. Their high-heat flux properties have been investigated by high energy laser and electron beam for the simulation of plasma disruption process of the future fusion reactors. And a study on eroded products of B4C/Cu FGM under transient thermal load of electron beam was performed. In the experiment, SEM and EDS analysis indicated that B4C and SiC were decomposed, carbon was preferentially evaporated under high thermal load, and a part of Si and Cu were melted, in addition, the splash of melted metal and the particle emission of brittle destruction were also found. Different erosive behaviors of carbon-based materials (CBMs) caused by laser and electron beam were also discussed

  19. Annual report on JEN-1 reactor

    International Nuclear Information System (INIS)

    In the annual report on the JEN-1 reactor the main features of the reactor operations and maintenance are described. The reactor has been critical for 1831 hours, what means 65,8% of the total working time. Maintenance and pool water contamination have occupied the rest of the time. The maintenance schedule is shown in detail according to three subjects. The main failures and reactor scrams are also described. The daily maximum values of the water activity are given so as the activity of the air in the reactor hall. (Author)

  20. Metastable Equilibria for the Quaternary System Li2B4O7+ Na2B4O7+K2B4O7+H2Oat15℃

    Institute of Scientific and Technical Information of China (English)

    SANG,Shi-Hua; YIN,Hui-An; NI,Shi-Jun; DENG,Miao

    2008-01-01

    Metastable equilibrium solubilities and such physico-chemical properties as densities, conductivity, pH, refractive index and viscosity of the solution for the quaternary system Li2B4O7+Na2B4O7+K2B4O7+H2O at 15℃ were determined experimentally. According to the experimental data, the metastable equilibrium phase diagram was plotted. In the metastable phase diagram, there are one invariant point, three univariant curves, and three fields of crystallization: Li2B2O4·16H2O, Na2B4O7·10H2O, and K2B4O7·4H2O. Potassium borate (K2B4O7·4H2O) has the smallest crystallization field and sodium borate (borax) has the biggest one. Also, the relationship diagram between the properties and the ion concentration of solution was constructed. It can be seen from the relationship diagram that the metastable equilibrium solution density values, viscosity values and refractive index values are increased apparently with the rise of lithium borate concentration, reaching the maximum values at invariant point F. Electrical conductivity values and pH values, however, fall down with the rise of ion concentration on the whole.

  1. Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

    International Nuclear Information System (INIS)

    Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus

  2. Service hall in Number 1 Fukushima Nuclear Power Station, Tokyo Electric Power Company, Inc

    International Nuclear Information System (INIS)

    There are six BWR type nuclear power plants in the Number 1 Fukushima Nuclear Power Station, Tokyo Electric Power Company, Inc. The service hall of the station is located near the entrance of the station. In the center of this service hall, there is the model of a nuclear reactor of full scale. This mock-up shows the core region in the reactor pressure vessel for the number one plant. The diameter and the thickness of the pressure vessel are about 5 m and 16 cm, respectively. The fuel assemblies and control rods are set just like the actual reactor, and the start-up operation of the reactor is shown colorfully and dynamically by pushing a button. When the control rods are pulled out, the boiling of water is demonstrated. The 1/50 scale model of the sixth plant with the power generating capacity of 1100 MWe is set, and this model is linked to the mock-up of reactor written above. The operations of a recirculating loop, a turbine and a condenser are shown by switching on and off lamps. The other exhibitions are shielding concrete wall, ECCS model, and many kinds of panels and models. This service hall is incorporated in the course of study and observation of civics. The good environmental effects to fishes and shells are explained in this service hall. Official buildings and schools are built near the service hall utilizing the tax and grant concerning power generation. This service hall contributes to give much freedom from anxiety to the public by the tour. (Nakai, Y.)

  3. EphB4 localises to the nucleus of prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Mertens-Walker, Inga, E-mail: inga.mertenswalker@qut.edu.au [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia); Lisle, Jessica E. [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia); Nyberg, William A. [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Stephens, Carson R. [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia); Burke, Leslie [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Rutkowski, Raphael; Herington, Adrian C.; Stephenson, Sally-Anne [Institute of Health and Biomedical Innovation, Queensland University of Technology, Woolloongabba, QLD (Australia); Australian Prostate Cancer Research Centre—Queensland, Translational Research Institute, 37 Kent Street, Woolloongabba 4102, QLD (Australia)

    2015-04-10

    The EphB4 receptor tyrosine kinase is over-expressed in a variety of different epithelial cancers including prostate where it has been shown to be involved in survival, migration and angiogenesis. We report here that EphB4 also resides in the nucleus of prostate cancer cell lines. We used in silico methods to identify a bipartite nuclear localisation signal (NLS) in the extracellular domain and a monopartite NLS sequence in the intracellular kinase domain of EphB4. To determine whether both putative NLS sequences were functional, fragments of the EphB4 sequence containing each NLS were cloned to create EphB4NLS-GFP fusion proteins. Localisation of both NLS-GFP proteins to the nuclei of transfected cells was observed, demonstrating that EphB4 contains two functional NLS sequences. Mutation of the key amino residues in both NLS sequences resulted in diminished nuclear accumulation. As nuclear translocation is often dependent on importins we confirmed that EphB4 and importin-α can interact. To assess if nuclear EphB4 could be implicated in gene regulatory functions potential EphB4-binding genomic loci were identified using chromatin immunoprecipitation and Lef1 was confirmed as a potential target of EphB4-mediated gene regulation. These novel findings add further complexity to the biology of this important cancer-associated receptor. - Highlights: • The EphB4 protein can be found in the nucleus of prostate cancer cell lines. • EphB4 contains two functional nuclear localisation signals. • Chromatin immunoprecipitation has identified potential genome sequences to which EphB4 binds. • Lef1 is a confirmed target for EphB4-mediated gene regulation.

  4. EphB4 localises to the nucleus of prostate cancer cells

    International Nuclear Information System (INIS)

    The EphB4 receptor tyrosine kinase is over-expressed in a variety of different epithelial cancers including prostate where it has been shown to be involved in survival, migration and angiogenesis. We report here that EphB4 also resides in the nucleus of prostate cancer cell lines. We used in silico methods to identify a bipartite nuclear localisation signal (NLS) in the extracellular domain and a monopartite NLS sequence in the intracellular kinase domain of EphB4. To determine whether both putative NLS sequences were functional, fragments of the EphB4 sequence containing each NLS were cloned to create EphB4NLS-GFP fusion proteins. Localisation of both NLS-GFP proteins to the nuclei of transfected cells was observed, demonstrating that EphB4 contains two functional NLS sequences. Mutation of the key amino residues in both NLS sequences resulted in diminished nuclear accumulation. As nuclear translocation is often dependent on importins we confirmed that EphB4 and importin-α can interact. To assess if nuclear EphB4 could be implicated in gene regulatory functions potential EphB4-binding genomic loci were identified using chromatin immunoprecipitation and Lef1 was confirmed as a potential target of EphB4-mediated gene regulation. These novel findings add further complexity to the biology of this important cancer-associated receptor. - Highlights: • The EphB4 protein can be found in the nucleus of prostate cancer cell lines. • EphB4 contains two functional nuclear localisation signals. • Chromatin immunoprecipitation has identified potential genome sequences to which EphB4 binds. • Lef1 is a confirmed target for EphB4-mediated gene regulation

  5. Iodine Hall Thruster

    Science.gov (United States)

    Szabo, James

    2015-01-01

    Iodine enables dramatic mass and cost savings for lunar and Mars cargo missions, including Earth escape and near-Earth space maneuvers. The demonstrated throttling ability of iodine is important for a singular thruster that might be called upon to propel a spacecraft from Earth to Mars or Venus. The ability to throttle efficiently is even more important for missions beyond Mars. In the Phase I project, Busek Company, Inc., tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high-flow iodine feed system and supported by an existing Busek hollow cathode flowing xenon gas. The Phase I propellant feed system was evolved from a previously demonstrated laboratory feed system. Throttling of the thruster between 2 and 11 kW at 200 to 600 V was demonstrated. Testing showed that the efficiency of iodine fueled BHT-8000 is the same as with xenon, with iodine delivering a slightly higher thrust-to-power (T/P) ratio. In Phase II, a complete iodine-fueled system was developed, including the thruster, hollow cathode, and iodine propellant feed system. The nominal power of the Phase II system is 8 kW; however, it can be deeply throttled as well as clustered to much higher power levels. The technology also can be scaled to greater than 100 kW per thruster to support megawatt-class missions. The target thruster efficiency for the full-scale system is 65 percent at high specific impulse (Isp) (approximately 3,000 s) and 60 percent at high thrust (Isp approximately 2,000 s).

  6. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  7. Hierarchical nature of the quantum Hall effects.

    Science.gov (United States)

    Bonderson, Parsa

    2012-02-10

    I demonstrate that the wave function for a ν=n+ν[over ˜] quantum Hall state with Landau levels 0,1,…,n-1 filled and a filling fraction ν[over ˜] quantum Hall state with 0Hall states. It follows that the composite fermion description of fractional quantum Hall states fits within the hierarchy theory of the fractional quantum Hall effect. I also demonstrate this directly by generating the composite fermion ground-state wave functions via application of the hierarchy construction to fractional quantum Hall states, starting from the ν=1/m Laughlin states.

  8. Ab initio search for global minimum structures of neutral and anionic B4H4 clusters

    International Nuclear Information System (INIS)

    Graphical abstract: Low-lying isomers of the B4H4 cluster found by sampling potential energy surface with the Coalescence Kick method. Research highlights: → B4H4 has a planar rather than a tetrahedral global minimum structure. → The B4H4- anion global minimum is a distorted tetrahedral structure. → Theoretical vertical detachment energies included here can help interpret future photoelectron spectroscopic study of the B4H4- anion. → Bonding analysis using AdNDP reveals 4-center bonding in B4H4 and B4H4- clusters. - Abstract: Potential energy surfaces of neutral and anionic B4H4 clusters were sampled using a Coalescence Kick method. A diverse set of global minimum structures and low-lying isomers was found for the studied clusters. Theoretical vertical electron detachment energies were calculated for the two lowest isomers of B4H4-, which could help to assign them in the future experimentally observed photoelectron spectra of the anion. Chemical bonding analysis for the global minimum structures and low-lying isomers of B4H4 and B4H4- was performed using the Adaptive Natural Density Partitioning method.

  9. Proyecto de remodelación de la calle Francesc Macià, entre avenida Calderó y la calle Àngel Guimerà

    OpenAIRE

    Viñals Burgo, Enrique

    2011-01-01

    El Ayuntamiento de Mollet del Vallés, cree oportuna la remodelación de la calle Francesc Macià, entre avenida Calderó y la calle Àngel Guimerà y convertirla en una calle peatonal. Es una calle que sirve de conexión entre el centro de la población y la estación de Renfe Mollet – St. Fost, cuya única parte no peatonal, es la que se va a proyectar. Además en esta calle se encuentra el colegio público Nicolás Longarón, cuya entrada principal, se da por esta misma calle a remodelar....

  10. Análisis de los factores de riesgo de prematuridad en el Hospital Calderón Guardia de enero a agosto 2001

    Directory of Open Access Journals (Sweden)

    Bernardo Goldstein Sandoval

    2003-03-01

    Full Text Available En esta investigación se plantea los factores asociados al riesgo de prematuridad que incide notablemente en la salud pública costarricense. El objetivo general del estudio es: Analizar los factores de riesgo de prematuridad en el Hospital Calderón Guardia de enero a agosto 2001 mediante un modelo de Regresión Logística. Para lograr este propósito se determinaron los factores que presentan asociación significativa con el parto prematuro y se cuantificó el grado de asociación entre factores de riesgo y parto de pretérmino. Métodos: Este es un estudio retrospectivo que analiza expedientes médicos de pacientes embarazadas que tuvieron su parto en el Hospital Calderón Guardia de enero a agosto 2001. A una muestra representativa de un total de 5061 expedientes del Servicio de Obstetricia del Hospital Calderón Guardia, en relación con nacimientos ocurridos de enero a agosto 2001 se les aplicó una revisión general, con el propósito básico de identificar factores de riesgo asociados con prematuridad. Para lograr lo anterior se tomó una muestra de expedientes estadísticamente significativa. El total de expedientes es de 5061 y el tamaño de la muestra es de 291, con un nivel de confianza de un 95% y con un error máximo permisible de un 5%. Resultados: El 43% de la muestra de partos (290 partos de 5061 ocurridos entre enero y agosto de 2001 en el Hospital Calderón Guardia corresponden a prematuros (casos y el 57% restantes son de término (controles. La anterior muestra se relaciona con un nivel de confianza del 95%. El modelo de Regresión Logística obtenido se puede representar mediante el logit: _(x= 2,5022 - 0,0241DS - 0,283CP + 3,077PREPREM + 2,206 HTAPRE + 0,649 HTAIE + 1,355 RPM + 3,174 GEMELOS Los valores estimados de los coeficientes b no pueden interpretarse directamente como probabilidades, sino como variaciones en el índice estimado de propensión (score. Las variables que resultaron estadísticamente significativas al

  11. Timectomía por miastenia gravis en el Hospital Dr. Rafael Angel Calderón Guardia: Reporte de 24 casos

    Directory of Open Access Journals (Sweden)

    José A Mainieri Hidalgo

    2000-06-01

    Full Text Available Antecedentes: La miastenia gravis es una enfermedad autoinmune cuya etiología aún no está claramente definida. Desde 1912 se describió mejoría del cuadro posterior a timectomía. Este procedimiento es actualmente una de las formas aceptadas para su tratamiento. El objetivo del presente trabajo fue estudiar los resultados de la timectomía para el tratamiento de la miastenia gravis en el Hospital Rafael Angel Calderón Guardia. Materiales y Métodos: Estudio retrospectivo, basado en la revisión de los expedientes de 24 pacientes, a quienes se les realizó timectomía como parte de su tratamiento de miastenia gravis entre enero de 1992 y mayo de 1999, en el Hospital Dr. Rafael Angel Calderón Guardia. Resultados: Se encontró que un 75% de los pacientes presentaron una franca mejoría, 17% permaneció en igual condición y un 8% empeoró. No se observó diferencia en la evolución por sexo, edad o la presencia de timoma, sin embargo en los pacientes que presentaban únicamente síntomas oculares se dio una tendencia a persistir sintomáticos. Se observó que la preparación pre-operatoria del paciente con gamaglobulina y la modernización de la técnica anestésica disminuyó notablemente la necesidad de ventilación mecánica. Conclusión: La timectomía fue útil en el tratamiento del 75% de los pacientes, especialmente aquellos con no sólo ptosis palpebral y permitió disminuir la dosis de medicamentos en 12 de los 24 casos estudiados.

  12. Pressure effect on structural, elastic, and thermodynamic properties of tetragonal B4C4

    International Nuclear Information System (INIS)

    The compressibility, elastic anisotropy, and thermodynamic properties of the recently proposed tetragonal B4C4 (t-B4C4) are investigated under high temperature and high pressure by using of first-principles calculations method. The elastic constants, bulk modulus, shear modulus, Young’s modulus, Vickers hardness, Pugh’s modulus ratio, and Poisson’s ratio for t-B4C4 under various pressures are systematically explored, the obtained results indicate that t-B4C4 is a stiffer material. The elastic anisotropies of t-B4C4 are discussed in detail under pressure from 0 GPa to 100 GPa. The thermodynamic properties of t-B4C4, such as Debye temperature, heat capacity, and thermal expansion coefficient are investigated by the quasi-harmonic Debye model

  13. Pressure effect on structural, elastic, and thermodynamic properties of tetragonal B4C4

    Directory of Open Access Journals (Sweden)

    Baobing Zheng

    2015-03-01

    Full Text Available The compressibility, elastic anisotropy, and thermodynamic properties of the recently proposed tetragonal B4C4 (t-B4C4 are investigated under high temperature and high pressure by using of first-principles calculations method. The elastic constants, bulk modulus, shear modulus, Young’s modulus, Vickers hardness, Pugh’s modulus ratio, and Poisson’s ratio for t-B4C4 under various pressures are systematically explored, the obtained results indicate that t-B4C4 is a stiffer material. The elastic anisotropies of t-B4C4 are discussed in detail under pressure from 0 GPa to 100 GPa. The thermodynamic properties of t-B4C4, such as Debye temperature, heat capacity, and thermal expansion coefficient are investigated by the quasi-harmonic Debye model.

  14. SINTERING MECHANISM OF PURE AND CARBON_DOPED BORON CARBIDE%纯B4C和掺碳B4C的烧结机制

    Institute of Scientific and Technical Information of China (English)

    尹邦跃; 王零森; 方寅初

    2001-01-01

    Sintering densificaton process of pure and carbon_doped boron carbide powders with 0.42 μm median particle size were studied. Their sintering kinetic equations were obtained according to the influence of sintering temperature and holding time on linear shrinkage rate. The sintering mechanisms were investigated by comparing the characteristic exponent n. It is deduced that the main sintering mechanisms shill be volume diffusion and grain boundary diffusion for pure boron carbide and grain boundary diffusion for carbon_doped boron carbide showing activated sintering. The relative density of the carbon_doped B4C sintered at 2 160 ℃ for 45 min is more than 90%. Apart from those dissolved in the sintered boron carbide, the rest of the added carbon is in the form of free carbon, no new phase formed. Carbon_doping also result in a great decrease of B4C grain size.%研究了中位粒径为0.42 μm的纯B4C和掺碳B4C粉末的烧结致密化过程. 根据烧结温度和保温时间对线收缩率的影响,得出了它们的烧结动力学方程;由特征指数n值对比研究了它们的烧结致密化机制. 纯B4C的烧结致密化机制为体扩散和晶界扩散,而掺碳B4C的烧结机制主要为晶界扩散,因此,掺碳对B4C起到了活化烧结的作用. 在2 160 ℃烧结45 min,掺碳B4C烧结后相对密度大于90%. 掺入的碳除了固溶于B4C晶格中之外,其它均以游离石墨形式存在,不形成新相. 掺碳还导致B4C晶粒尺寸大大减小.

  15. Annual report on JEN-1 reactor; Informe periodico del Reactor JEN-1 correspondiente al ano 1971

    Energy Technology Data Exchange (ETDEWEB)

    Montes, J.

    1972-07-01

    In the annual report on the JEN-1 reactor the main features of the reactor operations and maintenance are described. The reactor has been critical for 1831 hours, what means 65,8% of the total working time. Maintenance and pool water contamination have occupied the rest of the time. The maintenance schedule is shown in detail according to three subjects. The main failures and reactor scrams are also described. The daily maximum values of the water activity are given so as the activity of the air in the reactor hall. (Author)

  16. Ultrahard boron-rich tantalum boride: Monoclinic TaB4

    International Nuclear Information System (INIS)

    Highlights: • A novel boron-rich m-TaB4 with monoclinic symmetry C2/m space group were predicted. • The m-TaB4 is a superhard material with Vickers hardness of 29 GPa. • Phonon dispersions and elastic constant analysis suggest that m-TaB4 is stable at ambient condition. • The high hardness of m-TaB4 is mainly originated from unique boron six-membered ring unit in the structure of m-TaB4. - Abstract: On the basis of the evolutionary methodology for crystal structure prediction, we have revealed a novel monoclinic C2/m structure TaB4 with planar six-membered ring boron network along the crystallographic b axis. We name it as m-TaB4. The calculations of elastic constants and phonon dispersion confirm that m-TaB4 is mechanical and dynamical stable. Further calculations predicate that this structure is an ultrahard material with a large hardness (29 GPa). The presence of strong covalent boron–boron bonds and planar six-membered ring boron network in m-TaB4 are crucial for its high hardness

  17. Bound values for Hall conductivity of heterogeneous medium under quantum Hall effect conditions

    Indian Academy of Sciences (India)

    V E Arkhincheev

    2008-02-01

    Bound values for Hall conductivity under quantum Hall effect (QHE) conditions in inhomogeneous medium has been studied. It is shown that bound values for Hall conductivity differ from bound values for metallic conductivity. This is due to the unusual character of current percolation under quantum Hall effect conditions.

  18. New insight into the Hall effect

    OpenAIRE

    Huang, X. Q.

    2009-01-01

    In this paper, we develop a unified theory for describing Hall effect in various electronic systems based on a pure electron picture (without the hole concept). We argue that the Hall effect is the magnetic field induced symmetry breaking of the charge carrier's spatial distribution. Due to the interaction of the charge carriers and the ion lattice, there are two possible symmetry breaking mechanisms which cause different signs of Hall coefficient in a Hall material. The scenario provides an ...

  19. Hall probes: physics and application to magnetometry

    OpenAIRE

    Sanfilippo, S.

    2011-01-01

    This lecture aims to present an overview of the properties of Hall effect devices. Descriptions of the Hall phenomenon, a review of the Hall effect device characteristics and of the various types of probes are presented. Particular attention is paid to the recent development of three-axis sensors and the related techniques to cancel the offsets and the planar Hall effect. The lecture introduces the delicate problem of the calibration of a three-dimensional sensor and ends with a section devot...

  20. Spin Hall Effect in Noncommutative Coordinates

    OpenAIRE

    Dayi, O. F.; Elbistan, M.

    2008-01-01

    A semiclassical constrained Hamiltonian system which was established to study dynamical systems of matrix valued non-Abelian gauge fields is employed to formulate spin Hall effect in noncommuting coordinates at the first order in the constant noncommutativity parameter theta . The method is first illustrated by studying the Hall effect on the noncommutative plane in a gauge independent fashion. Then, the Drude model type and the Hall effect type formulations of spin Hall effect are considered...

  1. Topological Nature of the Phonon Hall Effect

    OpenAIRE

    Zhang, Lifa; Ren, Jie; Wang, Jian-Sheng; Li, Baowen

    2010-01-01

    We provide a topological understanding on phonon Hall effect in dielectrics with Raman spinphonon coupling. A general expression for phonon Hall conductivity is obtained in terms of the Berry curvature of band structures. We find a nonmonotonic behavior of phonon Hall conductivity as a function of magnetic field. Moreover, we observe a phase transition in phonon Hall effect, which corresponds to the sudden change of band topology, characterized by the altering of integer Chern numbers. This c...

  2. Phase Diagram of Integer Quantum Hall Effect

    OpenAIRE

    Sheng, D. N.; Weng, Z. Y.

    1999-01-01

    The phase diagram of integer quantum Hall effect is numerically determined in the tight-binding model, which can account for overall features of recently obtained experimental phase diagram. In particular, the quantum Hall plateaus are terminated by two distinct insulating phases, characterized by the Hall resistance with classic and quantized values, respectively, which is also in good agreement with experiments.

  3. A Gift for Reading Hall No. 1

    Science.gov (United States)

    MacWilliams, Bryon

    2009-01-01

    In this article, the author describes Reading Hall No. 1 of the Russian State Library. He was placed in the first reading hall in the mid-1990s, when the Russian government still honored Soviet traditions of granting certain privileges to certain foreigners. In the first hall, the rules are different. He can request as many books as he wants. He…

  4. Hall effect in NS and SNS junctions

    OpenAIRE

    Zhou, F.; Spivak, B.

    1997-01-01

    Hall effect in SN and SNS junctions is considered. It is shown that at small temperature the Hall voltage is significantly suppressed as compared to its normal metal value. The time dependence of the Hall voltage in SNS junctions has a form of narrow pulses with the Josephson frequency.

  5. The Other Hall Effect: College Board Physics

    Science.gov (United States)

    Sheppard, Keith; Gunning, Amanda M.

    2013-01-01

    Edwin Herbert Hall (1855-1938), discoverer of the Hall effect, was one of the first winners of the AAPT Oersted Medal for his contributions to the teaching of physics. While Hall's role in establishing laboratory work in high schools is widely acknowledged, his position as chair of the physics section of the Committee on College Entrance…

  6. Effect of increased HoxB4 on human megakaryocytic development

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Yiming [Department of Pathology, The Ohio State University, Columbus, OH (United States); Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH (United States); Sullenbarger, Brent [Department of Pathology, The Ohio State University, Columbus, OH (United States); Lasky, Larry C., E-mail: Lasky.4@osu.edu [Department of Pathology, The Ohio State University, Columbus, OH (United States); Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH (United States)

    2010-07-30

    Research highlights: {yields} HoxB4 overexpression in human TF1 cells increased the expression of CD61 and CD41a. {yields} HoxB4 fusion protein enhanced megakaryocytic development of CD34{sup +} cord blood cells. {yields} Ectopic HoxB4 increased Tpo receptor expression and decreased c-Myb expression. {yields} HoxB4 RNA silencing increased c-Myb expression and decreased Fli-1 expression. -- Abstract: In order to produce clinically useful quantities of platelets ex vivo we may need to firstly enhance early self-renewal of hematopoietic stem cells (HSCs) and/or megakaryocyte (Mk) progenitors. The homeodomain transcription factor HoxB4 has been shown to be an important regulator of stem cell renewal and hematopoiesis; however, its effect on megakaryopoiesis is unclear. In this study, we investigated the effect of HoxB4 overexpression or RNA silencing on megakaryocytic development in the human TF1 progenitor cell line; we then used recombinant tPTD-HoxB4 fusion protein to study the effect of exogenous HoxB4 on megakaryocytic development of human CD34 positively-selected cord blood cells. We found that ectopic HoxB4 in TF1 cells increased the antigen expression of CD61and CD41a, increased the gene expression of thrombopoietin receptor (TpoR), Scl-1, Cyclin D1, Fog-1 and Fli-1 while it decreased c-Myb expression. HoxB4 RNA silencing in TF1 cells decreased the expression of CD61 and CD41a and decreased Fli-1 expression while it increased the expression of c-Myb. Recombinant tPTD-HoxB4 fusion protein increased the percentages and absolute numbers of CD41a and CD61 positive cells during megakaryocytic differentiation of CD34 positively-selected cord blood cells and increased the numbers of colony-forming unit-megakaryocyte (CFU-Mk). Adding tPTD-HoxB4 fusion protein increased the gene expression of TpoR, Cyclin D1, Fog-1 and Fli-1 while it inhibited c-Myb expression. Our data suggest that increased HoxB4 enhanced early megakaryocytic development in human TF1 cells and CD34

  7. Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells.

    Science.gov (United States)

    Okazaki, Shogo; Nakatani, Fumi; Masuko, Kazue; Tsuchihashi, Kenji; Ueda, Shiho; Masuko, Takashi; Saya, Hideyuki; Nagano, Osamu

    2016-01-29

    The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. PMID:26780728

  8. Comparison of nanostructured Al/B4C composite produced by ARB and Al/B4C composite produced by RRB process

    International Nuclear Information System (INIS)

    Research highlights: → The SEM microstructures revealed the well distributed B4C particles in the aluminum matrix for both the composites. → The TEM analysis showed the nanostructured Al/B4C composite was produced by the ARB process successfully. → The ductility (elongation) of the RRB processed composite is higher than that of the ARB processed composite. → The microhardness of the ARB processed composite is higher than that of the RRB processed composite. - Abstract: In the present study, Al/B4C composites were produced and compared in the form of sheets, through accumulative roll bonding (ARB) and repeated roll bonding (RRB) processes. The microstructure of the composites fabricated by both the methods, revealed by scanning electron microscopy (SEM), showed the B4C particles properly distributed in the aluminum matrix. The average grain size of the ARB processed composite was about 186 nm by linear intercept method, based on transmission electron microscopy (TEM) observations. Mechanical properties of the Al/B4C composites produced by two methods were investigated by tensile and hardness tests. The results showed that the tensile strength and hardness of the ARB and RRB processed composites increase with the number of cycles. However, the tensile strength and hardness of the ARB processed composite are much higher than those of the RRB processed composite. The tensile test results revealed that the elongation of the ARB processed composite is lower than that of the RRB processed composite.

  9. 75 FR 7467 - Gary E. Hall and Rita C. Hall; Notice of Application Accepted for Filing With the Commision...

    Science.gov (United States)

    2010-02-19

    ... Energy Regulatory Commission Gary E. Hall and Rita C. Hall; Notice of Application Accepted for Filing.... Applicant: Gary E. Hall and Rita C. Hall. e. Name of Project: Potter Creek Hydroelectric Project. f...: Mr. Gary E. Hall and Ms. Rita C. Hall, P.O. Box 133, Olney, MT 59927, (406) 881-2345. i. FERC...

  10. Quantum-Hall quantum bits

    OpenAIRE

    Yang, S. -R. Eric; Schliemann, John; MacDonald, A. H.

    2002-01-01

    Bilayer quantum Hall systems can form collective states in which electrons exhibit spontaneous interlayer phase coherence. We discuss the possibility of using bilayer quantum dot many-electron states with this property to create two-level systems that have potential advantages as quantum bits.

  11. Hall / Madle Mühlbach

    Index Scriptorium Estoniae

    Mühlbach, Madle

    2008-01-01

    Hallist värvusest interjööris, olles oma passiivsuses ja lakoonilisuses nii efektne, kui seda ilmestab mõni värvikam detail või neutraalne tasakaalustaja. Lk. 73 Eva Toome valitud halle esemeid müügivõrgust

  12. NPS Hall of Fame 2015

    OpenAIRE

    Naval Postgraduate School (U.S.)

    2015-01-01

    "The NPS Hall of Fame recognizes the accomplishments of NPS's most distinguished alumni and friends who, through the attainment of positions at the highest levels of public service, have made the greatest contributions to society, their nations and to the Naval Postgraduate School. "

  13. ATLAS Assembly Hall Open Day

    CERN Multimedia

    Patrice Loiez

    2004-01-01

    To mark the 50th Anniversary of the founding of CERN, a day of tours, displays and presentations was held in October 2004. The assembly halls for the experiments that were waiting to be installed on the LHC, such as ATLAS shown here, were transformed into display areas and cafés.

  14. B4G local area: high level requirements and system design

    DEFF Research Database (Denmark)

    Mogensen, Preben; Pajukoski, Kari; Raaf, Bernhard;

    2012-01-01

    A next generation Beyond 4G (B4G) radio access technology is expected to become available around 2020 in order to cope with the exponential increase of mobile data traffic. In this paper, research motivations and high level requirements for a B4G local area concept are discussed. Our suggestions...

  15. 26 CFR 20.2056(b)-4 - Marital deduction; valuation of interest passing to surviving spouse.

    Science.gov (United States)

    2010-04-01

    ... passing to surviving spouse. 20.2056(b)-4 Section 20.2056(b)-4 Internal Revenue INTERNAL REVENUE SERVICE... surviving spouse. (a) In general. The value, for the purpose of the marital deduction, of any deductible interest which passed from the decedent to his surviving spouse is to be determined as of the date of...

  16. 22 CFR 9b.4 - Department of State building press pass for technical crews.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Department of State building press pass for technical crews. 9b.4 Section 9b.4 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS GOVERNING... provide technical support on a daily basis for media correspondents assigned to the Department of...

  17. SHS/PHIP工艺制备Ti-C-B4C体系复相陶瓷%SHS/PHIP OF TI - C - B4 C CERAMICS

    Institute of Scientific and Technical Information of China (English)

    赵淑梅; 林红; 朱春城

    2006-01-01

    选用Ti、C、B、B4C为原料通过SHS工艺制备了不同配比的TiC-TiB2复合陶瓷,同时进行了Ti-C-B和Ti-C-B4C体系材料的对比实验,通过对不同体系材料的组织分析和性能测试,同时考虑到材料的价格性能比,表明用B4C替代B来制备TiC-TiB2复合陶瓷是可行的.

  18. On The Quantum Theory of Hall Effect

    OpenAIRE

    Ghaboussi, F.

    1996-01-01

    We discuss a model of both classical and integer quantum Hall-effect which is based on a semi-classical Schroedinger-Chern-Simons-action, where the Ohm-equations result as equations of motion. The quantization of the classical Chern-Simons-part of action under typical quantum Hall conditions results in the quantized Hall conductivity. We show further that the classical Hall-effect is described by a theory which arises as the classical limit of a theory of quantum Hall-effect. The model explai...

  19. Planar Hall effect bridge magnetic field sensors

    DEFF Research Database (Denmark)

    Henriksen, A.D.; Dalslet, Bjarke Thomas; Skieller, D.H.;

    2010-01-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can...... be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar...... Hall effect bridge sensors....

  20. Planar Hall effect bridge magnetic field sensors

    Science.gov (United States)

    Henriksen, A. D.; Dalslet, B. T.; Skieller, D. H.; Lee, K. H.; Okkels, F.; Hansen, M. F.

    2010-07-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar Hall effect bridge sensors.

  1. Optical Hall effect-model description: tutorial.

    Science.gov (United States)

    Schubert, Mathias; Kühne, Philipp; Darakchieva, Vanya; Hofmann, Tino

    2016-08-01

    The optical Hall effect is a physical phenomenon that describes the occurrence of magnetic-field-induced dielectric displacement at optical wavelengths, transverse and longitudinal to the incident electric field, and analogous to the static electrical Hall effect. The electrical Hall effect and certain cases of the optical Hall effect observations can be explained by extensions of the classic Drude model for the transport of electrons in metals. The optical Hall effect is most useful for characterization of electrical properties in semiconductors. Among many advantages, while the optical Hall effect dispenses with the need of electrical contacts, electrical material properties such as effective mass and mobility parameters, including their anisotropy as well as carrier type and density, can be determined from the optical Hall effect. Measurement of the optical Hall effect can be performed within the concept of generalized ellipsometry at an oblique angle of incidence. In this paper, we review and discuss physical model equations, which can be used to calculate the optical Hall effect in single- and multiple-layered structures of semiconductor materials. We define the optical Hall effect dielectric function tensor, demonstrate diagonalization approaches, and show requirements for the optical Hall effect tensor from energy conservation. We discuss both continuum and quantum approaches, and we provide a brief description of the generalized ellipsometry concept, the Mueller matrix calculus, and a 4×4 matrix algebra to calculate data accessible by experiment. In a follow-up paper, we will discuss strategies and approaches for experimental data acquisition and analysis. PMID:27505654

  2. Timectomía por miastenia gravis en el Hospital Dr. Rafael Angel Calderón Guardia: Reporte de 24 casos

    Directory of Open Access Journals (Sweden)

    José A Mainieri Hidalgo

    2000-06-01

    Full Text Available Antecedentes: La miastenia gravis es una enfermedad autoinmune cuya etiología aún no está claramente definida. Desde 1912 se describió mejoría del cuadro posterior a timectomía. Este procedimiento es actualmente una de las formas aceptadas para su tratamiento. El objetivo del presente trabajo fue estudiar los resultados de la timectomía para el tratamiento de la miastenia gravis en el Hospital Rafael Angel Calderón Guardia. Materiales y Métodos: Estudio retrospectivo, basado en la revisión de los expedientes de 24 pacientes, a quienes se les realizó timectomía como parte de su tratamiento de miastenia gravis entre enero de 1992 y mayo de 1999, en el Hospital Dr. Rafael Angel Calderón Guardia. Resultados: Se encontró que un 75% de los pacientes presentaron una franca mejoría, 17% permaneció en igual condición y un 8% empeoró. No se observó diferencia en la evolución por sexo, edad o la presencia de timoma, sin embargo en los pacientes que presentaban únicamente síntomas oculares se dio una tendencia a persistir sintomáticos. Se observó que la preparación pre-operatoria del paciente con gamaglobulina y la modernización de la técnica anestésica disminuyó notablemente la necesidad de ventilación mecánica. Conclusión: La timectomía fue útil en el tratamiento del 75% de los pacientes, especialmente aquellos con no sólo ptosis palpebral y permitió disminuir la dosis de medicamentos en 12 de los 24 casos estudiados.Background: Miastenia gravis is an autoimmune disease, its etiology has not been defined clearly. The improvement of the clinical manifestations after thymectomy was first describes in 1912; and this procedure has become in one of the therapeutic alternativas for the disease nowadays. The aim of the present study was to investigase the results of thymectomy for miastenia gravis in the Hospital Dr. R. A. Calderón Guardia. Materials and Methods: Retrospective study, based in the revision of the clinical

  3. Vigilancia epidemiológica para el infarto agudo al miocardio, experiencia obtenida en el Hospital Calderón Guardia

    Directory of Open Access Journals (Sweden)

    Manrique leal-Mateos

    2005-04-01

    Full Text Available Justificación y objetivo: Debido a que el infarto agudo al miocardio representa una de las principales causas de muerte en nuestro país, la autoridades de salud decidieron, en 2003, incluirlo como una enfermedad sujeta a vigilancia epidemiológica. El presente trabajo tiene como propósito dar a conocer la información más sobresaliente del sistema de vigilancia epidemiológica para el IAM, implementado en el servicio de Medicina Interna del Hospital Calderón Guardia. Metodología: Se realizó un análisis descriptivo de la información recolectada desde el 1 de octubre de 2003, al 30 de septiembre de 2004. Las variables cualitativas se analizaron mediante frecuencias y proporciones. Las variables cuantitativas se expresaron por medio de medidas de tendencia central y dispersión. Las diferencias entre promedios y proporciones se compararon mediante la prueba de t Student. La significancia estadística fue fijada en p Rationale and Objective: Since acute myocardial infarction represents one of the main causes of death in our country, the health authorities decided in the year 2003 to include it as an illness subject to epidemiological surveillance. The present paper has as its purpose to give the most salient information of the epidemiological surveillance system for myocardial infarction implemented in the Internal Medicine service of the Calderón Guardia hospital. Methods: We did a descriptive analysis of the information collected since October First, 2003 and until September the 30th., 2004. Qualitative variables were analyzed with frequencies and proportions. The quantitative variables were expressed by means of measures of central tendency as well as measures of dispersion. The differences between averages and proportions were compared with the Student's t test. Statistical significance was fixed at less or equal to 0.05. We used the Epi Info program for data processing. Results: The age average was 64.6 years (S.D. + 12.2 years. 66

  4. Recombination luminescence in Li2B4O7 doped with manganese and copper

    International Nuclear Information System (INIS)

    Non-irradiated and irradiated ceramics of Li2B4O7:Mn, Li2B4O7:Mn,Be, and Li2B4O7:Mn,Cu were studied using electron paramagnetic resonance and luminescence spectroscopy. The emission of Mn2+ centres is observed in the thermoluminescence spectra of the low-temperature and dosimetric high-temperature glow peaks in irradiated samples. Arguments are given in favour of hole mobility being responsible for the dosimetric thermoluminescence peak at 490 K in Li2B4O7:Mn. The co-doping of Li2B4O7:Mn with Cu+ is shown to increase the sensitivity of the material to ionizing radiation. -- Highlights: ► Doped Li2B4O7 ceramics were studied by EPR and optical spectroscopy. ► In Li2B4O7:Mn ceramics Mn2+ emission is observed for the TSL peaks at 90 and 490 K ► We propose the release of holes to be responsible for the dosimetric peak at 490 K

  5. Investigation of the expression of the EphB4 receptor tyrosine kinase in prostate carcinoma

    Directory of Open Access Journals (Sweden)

    Douglas Evelyn L

    2005-09-01

    Full Text Available Abstract Background The EphB4 receptor tyrosine kinase has been reported as increased in tumours originating from several different tissues and its expression in a prostate cancer xenograft model has been reported. Methods RT-PCR, western blotting and immunohistochemical techniques were used to examine EphB4 expression and protein levels in human prostate cancer cell lines LNCaP, DU145 and PC3. Immunohistochemistry was also used to examine localisation of EphB4 in tissue samples from 15 patients with prostate carcinomas. Results All three prostate cancer cell lines expressed the EphB4 gene and protein. EphB4 immunoreactivity in vivo was significantly greater in human prostate cancers as compared with matched normal prostate epithelium and there appeared to be a trend towards increased expression with higher grade disease. Conclusion EphB4 is expressed in prostate cancer cell lines with increased expression in human prostate cancers when compared with matched normal tissue. EphB4 may therefore be a useful anti-prostate cancer target.

  6. Symmetric functions and Hall polynomials

    CERN Document Server

    MacDonald, Ian Grant

    1998-01-01

    This reissued classic text is the acclaimed second edition of Professor Ian Macdonald's groundbreaking monograph on symmetric functions and Hall polynomials. The first edition was published in 1979, before being significantly expanded into the present edition in 1995. This text is widely regarded as the best source of information on Hall polynomials and what have come to be known as Macdonald polynomials, central to a number of key developments in mathematics and mathematical physics in the 21st century Macdonald polynomials gave rise to the subject of double affine Hecke algebras (or Cherednik algebras) important in representation theory. String theorists use Macdonald polynomials to attack the so-called AGT conjectures. Macdonald polynomials have been recently used to construct knot invariants. They are also a central tool for a theory of integrable stochastic models that have found a number of applications in probability, such as random matrices, directed polymers in random media, driven lattice gases, and...

  7. Electron dynamics in Hall thruster

    Science.gov (United States)

    Marini, Samuel; Pakter, Renato

    2015-11-01

    Hall thrusters are plasma engines those use an electromagnetic fields combination to confine electrons, generate and accelerate ions. Widely used by aerospace industries those thrusters stand out for its simple geometry, high specific impulse and low demand for electric power. Propulsion generated by those systems is due to acceleration of ions produced in an acceleration channel. The ions are generated by collision of electrons with propellant gas atoms. In this context, we can realize how important is characterizing the electronic dynamics. Using Hamiltonian formalism, we derive the electron motion equation in a simplified electromagnetic fields configuration observed in hall thrusters. We found conditions those must be satisfied by electromagnetic fields to have electronic confinement in acceleration channel. We present configurations of electromagnetic fields those maximize propellant gas ionization and thus make propulsion more efficient. This work was supported by CNPq.

  8. Receptor protein tyrosine kinase EphB4 is up-regulated in colon cancer

    OpenAIRE

    Hewett Peter J; Douglas Evelyn L; Slomka Stefan; Stephenson Sally-Anne; Hardingham Jennifer E

    2001-01-01

    Abstract Background We have used commercially available cDNA arrays to identify EphB4 as a gene that is up-regulated in colon cancer tissue when compared with matched normal tissue from the same patient. Results Quantitative RT-PCR analysis of the expression of the EphB4 gene has shown that its expression is increased in 82% of tumour samples when compared with the matched normal tissue from the same patient. Using immunohistochemistry and Western analysis techniques with an EphB4-specific an...

  9. Intracellular glycosidases of human colon Bacteroides ovatus B4-11.

    OpenAIRE

    Reddy, N R; Palmer, J K; Pierson, M. D.; Bothast, R J

    1984-01-01

    Activity of various glycosidases in the intracellular enzyme fraction of Bacteroides ovatus B4-11 was investigated. During 120 h of incubation at 37 degrees C, ca. 30% of the crude hemicellulose was hydrolyzed by an intracellular enzyme fraction of strain B4-11. Xylose was the major sugar released from crude hemicellulose. Glycosidases (alpha-1,6-glucosidase, alpha-1,4-glucosidase, beta-1,4-glucosidase, and beta-1,4-xylosidase) were induced in B. ovatus B4-11 by crude hemicellulose and hetero...

  10. Al/ B4C Composites with 5 and 10 wt% Reinforcement Content Prepared by Powder Metallurgy

    International Nuclear Information System (INIS)

    The preparation, physical and mechanical properties of Al/ B4C composites with 5 and 10 wt.% reinforcement content were investigated. In order to obtain the feedstock with a low powder loading, B4C mixtures containing fine powders were investigated to obtain the optimal particle packing. The experimental results indicated that the fine containing 5 and 10 wt.% particles are able to prepare the feedstock with a good flowability. The composites fabricated by powder metallurgy have low densities and homogeneous microstructures. Additionally there is no interface reaction observed between the reinforcement and matrix by XRD analysis. The hardness of Al/ B4C composites prepared by powder metallurgy was high. (Author)

  11. Determination of related substances of Vitamin B4 Tablets by HPLC%HPLC法测定维生素B4片的有关物质

    Institute of Scientific and Technical Information of China (English)

    顾秋琴

    2014-01-01

    OBJECTIVE To establish a HPLC method to determine the related substances in Vitamin B 4 Tab-lets.METHODS The HPLC column was Waters SunFireTM C 18 (250mm ×4.6mm,5μm);the mobile phase was methanol-0.05mol· L-1 potassium dihydrogen phosphate solution-triethylamine (10∶90∶0.25 );the flow rate was 0.8 mL· min-1 ,the detection wavelength was 261 nm.RESULTS Vitamin B4 was separated well from the related substances;The reproducibility and precision of the method were good.CONCLUSION The method is simple ,ac-curate and sensitive.It can be used for the determination of the related substances of Vitamin B 4 Tablets.%目的:建立高效液相色谱法测定维生素B4片的有关物质。方法采用Waters SunFireTM C18柱(250mm ×4.6mm,5μm),流动相为甲醇-0.05mol· L-1磷酸二氢钾溶液-三乙胺(10∶90∶0.25),流速0.8mL· min -1,检测波长261nm。结果主峰与各降解产物峰的分离良好,方法的精密度良好。结论本方法简便、准确、灵敏度高,可用于维生素B4片的有关物质检查。

  12. Hall-magnetohydrodynamic small-scale dynamos.

    Science.gov (United States)

    Gómez, Daniel O; Mininni, Pablo D; Dmitruk, Pablo

    2010-09-01

    Magnetic field generation by dynamo action is often studied within the theoretical framework of magnetohydrodynamics (MHD). However, for sufficiently diffuse media, the Hall effect may become non-negligible. We present results from three-dimensional simulations of the Hall-MHD equations subjected to random nonhelical forcing. We study the role of the Hall effect in the dynamo efficiency for different values of the Hall parameter. For small values of the Hall parameter, the small-scale dynamo is more efficient, displaying faster growth and saturating at larger amplitudes of the magnetic field. For larger values of the Hall parameter, saturation of the magnetic field is reached at smaller amplitudes than in the MHD case. We also study energy transfer rates among spatial scales and show that the Hall effect produces a reduction of the direct energy cascade at scales larger than the Hall scale, therefore leading to smaller energy dissipation rates. Finally, we present results stemming from simulations at large magnetic Prandtl numbers, which is the relevant regime in the hot and diffuse interstellar medium. In the range of magnetic Prandtl numbers considered, the Hall effect moves the peak of the magnetic energy spectrum as well as other relevant magnetic length scales toward the Hall scale. PMID:21230195

  13. Viscosity of Quantum Hall Fluids

    OpenAIRE

    Avron, J. E.; Seiler, R.; Zograf, P. G.

    1995-01-01

    The viscosity of quantum fluids with an energy gap at zero temperature is non-dissipative and is related to the adiabatic curvature on the space of flat background metrics (which plays the role of the parameter space). For a quantum Hall fluid on two dimensional tori this viscosity is computed. In this case the average viscosity is quantized and is proportional to the total magnetic flux through the torus.

  14. Automated Micro Hall Effect measurements

    DEFF Research Database (Denmark)

    Petersen, Dirch Hjorth; Henrichsen, Henrik Hartmann; Lin, Rong;

    2014-01-01

    With increasing complexity of processes and variety of materials used for semiconductor devices, stringent control of the electronic properties is becoming ever more relevant. Collinear micro four-point probe (M4PP) based measurement systems have become high-end metrology methods for characteriza...... for characterization and monitoring of sheet resistance as well as sheet carrier density and mobility via the Micro Hall Effect (MHE) method....

  15. Chemical State Mapping of Degraded B4C Control Rod Investigated with Soft X-ray Emission Spectrometer in Electron Probe Micro-analysis

    Science.gov (United States)

    Kasada, R.; Ha, Y.; Higuchi, T.; Sakamoto, K.

    2016-05-01

    B4C is widely used as control rods in light water reactors, such as the Fukushima Daiichi nuclear power plant, because it shows excellent neutron absorption and has a high melting point. However, B4C can melt at lower temperatures owing to eutectic interactions with stainless steel and can even evaporate by reacting with high-temperature steam under severe accident conditions. To reduce the risk of recriticality, a precise understanding of the location and chemical state of B in the melt core is necessary. Here we show that a novel soft X-ray emission spectrometer in electron probe microanalysis can help to obtain a chemical state map of B in a modeled control rod after a high-temperature steam oxidation test.

  16. Luminescence properties of SrB4O7:Sm2+ for light conversion agent

    Institute of Scientific and Technical Information of China (English)

    SUN Jiayue; ZHU Jicheng; LIU Xiaotang; DU Haiyan

    2012-01-01

    A deep red-emitting SrB4O7:Sm2+ phosphor for light conversion agent was synthesized by the conventional solid-state reaction.X-ray powder diffraction (XRD) analysis confirmed the phase formation of SrB4O7:Sm2+ materials.Results of luminescence properties showed that the phosphor could be efficiently excited by the UV-vis light region from 250-500 nm,and it exhibited deep red (685 nm) emission corresponding to 5D0→7F0 transition of Sm2+.The critical quenching concentration of Sm2+ in SrB4O7:Sm2+ phosphor was about 0.05,and the corresponding concentration quenching mechanism was verified to be the dipole-dipole interaction according to the Dexter's theory.The decay times had few alterations with different concentrations in SrB4O7:xSm2+ phosphor.

  17. Microstructure and Tensile Behaviour of B4C Reinforced ZA43 Alloy Composites

    Science.gov (United States)

    Adaveesh, B.; Halesh, G. M.; Nagaral, Madeva; Mohan Kumar, T. S.

    2016-09-01

    The work is carried out to investigate and study the mechanical properties of B4C reinforced ZA43 alloy metal matrix composites. In the present work ZA43 alloy is taken as the base matrix and B4C particulates as reinforcement material to prepare metal matrix composites by stir casting method. For metal matrix composites the reinforcement material was varied from 0 to 6 wt.% in steps of 3 wt.%. For each composite, the reinforcement particulates were preheated to a temperature of 300°C and dispersed into a vortex of molten ZA43 alloy. The microstructural characterization was done using scanning electron microscope. Mechanical properties like hardness, ultimate tensile strength and yield strength were evaluated as per ASTM standards. Further, scanning electron microphotographs revealed that there was uniform distribution of B4C particulates in ZA43 alloy matrix. Hardness, ultimate tensile strength and yield strength increased as wt.% of B4C increased in the base matrix.

  18. Thermoluminescence characteristics of gamma irradiated Li2B4O7:Cu nanophosphor

    Science.gov (United States)

    Chopra, Vibha; Singh, Lakhwant; Lochab, S. P.

    2013-07-01

    Nanocrystals of the Li2B4O7:Cu were synthesized by the combustion method using different concentrations of Cu. X-ray diffraction (XRD) spectra and transmission electron microscopy (TEM) image confirm the nanometric size of synthesized material. The thermal stability of phosphor was obtained by thermogravimetric analysis (TGA). TL characteristics of the synthesized Li2B4O7:Cu material doped with Cu of concentrations 1000 ppm and 2500 ppm were studied. It is observed that Li2B4O7:Cu doped with Cu (both 1000 ppm and 2500 ppm) exhibit a linear response in the range 1×100-5×103 Gy of gamma radiations. Finally the trapping parameters associated with the glow peaks were calculated using the glow curve deconvolution (GCD) glow fit method. Fading and reproducibility of phosphors were also studied and it was found that the Li2B4O7:Cu is quite suitable for radiation dosimetry.

  19. Spin Hall effect by surface roughness

    KAUST Repository

    Zhou, Lingjun

    2015-01-08

    The spin Hall and its inverse effects, driven by the spin orbit interaction, provide an interconversion mechanism between spin and charge currents. Since the spin Hall effect generates and manipulates spin current electrically, to achieve a large effect is becoming an important topic in both academia and industries. So far, materials with heavy elements carrying a strong spin orbit interaction, provide the only option. We propose here a new mechanism, using the surface roughness in ultrathin films, to enhance the spin Hall effect without heavy elements. Our analysis based on Cu and Al thin films suggests that surface roughness is capable of driving a spin Hall angle that is comparable to that in bulk Au. We also demonstrate that the spin Hall effect induced by surface roughness subscribes only to the side-jump contribution but not the skew scattering. The paradigm proposed in this paper provides the second, not if only, alternative to generate a sizable spin Hall effect.

  20. Supersymmetric Quantum Hall Effect on Fuzzy Supersphere

    OpenAIRE

    Hasebe, Kazuki

    2004-01-01

    Supersymmetric quantum Hall liquids are constructed on a supersphere in a supermonopole background. We derive a supersymmetric generalization of the Laughlin wavefunction, which is a ground state of a hard-core $OSp(1|2)$ invariant Hamiltonian. We also present excited topological objects, which are fractionally charged deficits made by super Hall currents. Several relations between quantum Hall systems and their supersymmetric extensions are discussed.

  1. Quantum Hall Physics in String Theory

    OpenAIRE

    Bergman, Oren

    2004-01-01

    In certain backgrounds string theory exhibits quantum Hall-like behavior. These backgrounds provide an explicit realization of the effective non-commutative gauge theory description of the fractional quantum Hall effect (FQHE), and of the corresponding large N matrix model. I review results on the string theory realization of the two-dimensional fractional quantum Hall fluid (FQHF), and describe new results on the stringy description of higher-dimensional analogs.

  2. Intrinsic spin Hall effect in noncubic crystals

    OpenAIRE

    Chudnovsky, E. M.

    2009-01-01

    We study the dependence of the intrinsic spin Hall effect on the crystal symmetry and geometry of experiment. The spin current is obtained and the Hall voltage caused by the polarization of the electron spins is computed. The unique dependence of the effect on the crystal symmetry permits the choice of geometry in which the spin Hall effect can be unambiguously distinguished from the effects due to the orbital motion of charge carriers and due to the magnetic field generated by the transport ...

  3. Multi-axis integrated Hall magnetic sensors

    Directory of Open Access Journals (Sweden)

    Popović Radivoje S.

    2007-01-01

    Full Text Available Conventional Hall magnetic sensors respond only to the magnetic field component perpendicular to the surface of the sensor die. Multi-axis sensing capability can be provided in the following two ways: (a by integrating magnetic flux concentrators on the die, and (b by using vertical Hall devices. Here we review the most important two-and three-axis integrated Hall magnetic sensors based on these concepts. Their applications include mapping of magnetic fields and sensing angular position.

  4. Unusual Properties of Anisotropic Hall Gas: Implication to Metrology of the Integer Quantum Hall Effect

    OpenAIRE

    Ishikawa, K; Maeda, N.

    2001-01-01

    Physical properties of anisotropic compressible quantum Hall states and their implications to integer quantum Hall effect are studied based on a mean field theory on the von Neumann lattice. It is found that the Hall gas has unusual thermodynamic properties such as negative pressure and negative compressibility and unusual transport properties. Transport properties and density profile of Hall gas states at half fillings agree with those of anisotropic states discovered experimentally in highe...

  5. Field Theory of Anisotropic Quantum Hall Gas: Metrology and a Novel Quantum Hall Regime

    OpenAIRE

    Ishikawa, K; Aoyama, T.; Ishizuka, Y.; Maeda, N.

    2003-01-01

    The von Neumann lattice representation is a convenient representation for studying several intriguing physics of quantum Hall systems. In this formalism, electrons are mapped to lattice fermions. A topological invariant expression of the Hall conductance is derived and is used for the proof of the integer quantum Hall effect in the realistic situation. Anisotropic quantum Hall gas is investigated based on the Hartree-Fock approximation in the same formalism. Thermodynamic properties, transpor...

  6. Study of influence content of TiB2 by reaction in situ B4C and TiC in mechanical properties on B4C ceramics

    International Nuclear Information System (INIS)

    The low density of ceramic materials promoted a change in research lines in the defense field. Research efforts and development directed to obtaining products of high density sintered of Al2O3, SiC and B4C, using different routes, both traditional as innovative, led to promising initial results, which justify the convergence of skills for the consolidation of research lines and the nationalization that sintered components of B4C with characteristics and properties compatible with the technical requirements established for the ballistic application. The low density of boron carbide (2.52 g/cm3) gives in the final product a weight approximately 30% lower than armor made of alumina (3.96 g/cm3). (author)

  7. Bridge connection of quantum Hall elementary devices

    CERN Document Server

    Callegaro, Luca

    2013-01-01

    Multiple-series and multiple-parallel connections of quantum Hall elementary devices allow the realization of multiple or fractional values of the quantized Hall resistance, rejecting the effect of contact and wiring resistances. We introduce here the multiple-bridge connection, which maintains the properties of multiple-series and parallel connections and allows more freedom in the choice of the topology of networks composed of quantum Hall elements, and the design of more efficient quantum Hall array resistance standards (and other devices). As an example, a 5-element network is analyzed in detail.

  8. Anomalous Hall effect in polycrystalline Ni films

    KAUST Repository

    Guo, Zaibing

    2012-02-01

    We systematically studied the anomalous Hall effect in a series of polycrystalline Ni films with thickness ranging from 4 to 200 nm. It is found that both the longitudinal and anomalous Hall resistivity increased greatly as film thickness decreased. This enhancement should be related to the surface scattering. In the ultrathin films (46 nm thick), weak localization corrections to anomalous Hall conductivity were studied. The granular model, taking into account the dominated intergranular tunneling, has been employed to explain this phenomenon, which can explain the weak dependence of anomalous Hall resistivity on longitudinal resistivity as well. © 2011 Elsevier Ltd. All rights reserved.

  9. Listening to the acoustics in concert halls

    Science.gov (United States)

    Beranek, Leo L.; Griesinger, David

    2001-05-01

    How does acoustics affect the symphonic music performed in a concert hall? The lecture begins with an illustrated discussion of the architectural features that influence the acoustics. Boston Symphony Hall, which was built in 1900 when only one facet of architectural design was known, now rates as one of the world's great halls. How this occurred will be presented. Music is composed with some acoustical environment in mind and this varies with time from the Baroque to the Romantic to the Modern musical period. Conductors vary their interpretation according to the hall they are in. Well-traveled listeners and music critics have favorite halls. The lecture then presents a list of 58 halls rank ordered according to their acoustical quality based on interviews of music critics and conductors. Modern acoustical measurements made in these halls are compared with their rankings. Music recordings will be presented that demonstrate how halls sound that have different measured acoustical parameters. Photographs of a number of recently built halls are shown as examples of how these known acoustical factors have been incorporated into architectural design.

  10. Anomalous Hall effect in localization regime

    Science.gov (United States)

    Wu, Lin; Zhu, Kai; Yue, Di; Tian, Yuan; Jin, Xiaofeng

    2016-06-01

    The anomalous Hall effect in the ultrathin film regime is investigated in Fe(001)(1-3 nm) films epitaxial on MgO(001). The logarithmic localization correction to longitudinal resistivity and anomalous Hall resistivity are observed at low temperature. We identify that the coefficient of skew scattering has a reduction from metallic to localized regime, while the contribution of side jump has inconspicuous change except for a small drop below 10 K. Furthermore, we discover that the intrinsic anomalous Hall conductivity decreases with the reduction of thickness below 2 nm. Our results provide unambiguous experimental evidence to clarify the problem of localization correction to the anomalous Hall effect.

  11. Lectures on the Quantum Hall Effect

    CERN Document Server

    Tong, David

    2016-01-01

    The purpose of these lectures is to describe the basic theoretical structures underlying the rich and beautiful physics of the quantum Hall effect. The focus is on the interplay between microscopic wavefunctions, long-distance effective Chern-Simons theories, and the modes which live on the boundary. The notes are aimed at graduate students in any discipline where $\\hbar=1$. A working knowledge of quantum field theory is assumed. Contents: 1. The Basics (Landau levels and Berry phase). 2. The Integer Quantum Hall Effect. 3. The Fractional Quantum Hall Effect. 4. Non-Abelian Quantum Hall States. 5. Chern-Simons Theories. 6. Edge Modes.

  12. Safety of research reactors (Design and Operation)

    International Nuclear Information System (INIS)

    The primary objective of this thesis is to conduct a comprehensive up-to-date literature review on the current status of safety of research reactor both in design and operation providing the future trends in safety of research reactors. Data and technical information of variety selected historical research reactors were thoroughly reviewed and evaluated, furthermore illustrations of the material of fuel, control rods, shielding, moderators and coolants used were discussed. Insight study of some historical research reactors was carried with considering sample cases such as Chicago Pile-1, F-1 reactor, Chalk River Laboratories,. The National Research Experimental Reactor and others. The current status of research reactors and their geographical distribution, reactor category and utilization is also covered. Examples of some recent advanced reactors were studied like safety barriers of HANARO of Korea including safety doors of the hall and building entrance and finger print identification which prevent the reactor from sabotage. On the basis of the results of this research, it is apparent that a high quality of safety of nuclear reactors can be attained by achieving enough robust construction, designing components of high levels of efficiency, replacing the compounds of the reactor in order to avoid corrosion and degradation with age, coupled with experienced scientists and technical staffs to operate nuclear research facilities.(Author)

  13. N Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The last of Hanfordqaodmasdkwaspemas7ajkqlsmdqpakldnzsdflss nine plutonium production reactors to be built was the N Reactor.This reactor was called a dual purpose...

  14. Growth process of Cu2Al6B4O17 whiskers

    International Nuclear Information System (INIS)

    The reactions occurred and growth process in the preparation of copper aluminum borate (Cu2Al6B4O17) whiskers based on flux method (Al2(SO4)3/CuSO4/H3BO3 as raw materials, K2SO4 as flux) were investigated. The thermogravimetric and differential scanning calorimetry analysis (TG-DSC), inductively coupled plasma atomic emission spectrum analysis (ICP-AES) and X-ray diffraction analysis (XRD) results of reactants mixture quenched at various temperatures and phase diagrams of K2SO4–Al2(SO4)3 system and B2O3–Al2O3 system showed that the reaction process proceeds through three steps: the formation and decomposition of two different kinds of potassium aluminum sulfate (K3Al(SO4)3 and KAl(SO4)2); the formation of aluminum borate (Al4B2O9) and decomposition of copper sulfate (CuSO4) and boric acid (H3BO3); growth and formation of copper aluminum borate (Cu2Al6B4O17) whiskers. The scanning electron microscopy (SEM) analysis results indicated that morphology in growth of Cu2Al6B4O17 whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. - Graphical abstract: The morphology in growth of Cu2Al6B4O17 whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. Highlights: ► Reaction process in the preparation of Cu2Al6B4O17 whiskers was researched systematically. ► Crystal growth mechanism of Cu2Al6B4O17 whiskers was proposed by theory and experiments. ► Properties of Cu2Al6B4O17 were analyzed by instruments, such as TG-DSC, ICP-AES, XRD and SEM.

  15. Partially split Hall bar: Tunneling in the bosonic integer quantum Hall effect

    OpenAIRE

    Mulligan, Michael; Fisher, Matthew P. A.

    2014-01-01

    We study point-contact tunneling in the integer quantum Hall state of bosons. This symmetry-protected topological state has electrical Hall conductivity equal to 2e^2/h and vanishing thermal Hall conductivity. In contrast to the integer quantum Hall state of fermions, a point contact can have a dramatic effect on the low-energy physics. In the absence of disorder, a point contact generically leads to a partially split Hall bar geometry. We describe the resulting intermediate fixed point via t...

  16. The Partially-Split Hall Bar: Tunneling in the Bosonic Integer Quantum Hall Effect

    OpenAIRE

    Mulligan, Michael; Fisher, Matthew P. A.

    2013-01-01

    We study point-contact tunneling in the integer quantum Hall state of bosons. This symmetry-protected topological state has electrical Hall conductivity equal to $2 e^2/h$ and vanishing thermal Hall conductivity. In contrast to the integer quantum Hall state of fermions, a point contact can have a dramatic effect on the low energy physics. In the absence of disorder, a point contact generically leads to a partially-split Hall bar geometry. We describe the resulting intermediate fixed point vi...

  17. The hall effect in magnetic reconnection: Hybrid versus Hall-less hybrid simulations

    Science.gov (United States)

    Malakit, K.; Cassak, P. A.; Shay, M. A.; Drake, J. F.

    2009-04-01

    To understand the role of the Hall effect during fast magnetic reconnection, hybrid simulations with and without the Hall term in the generalized Ohm's Law are compared, as done originally by Karimabadi et al. (2004). It is found that reconnection with the Hall term is fast, but reconnection in the so-called Hall-less hybrid simulations is Sweet-Parker like (slow) when the resistivity is constant and uniform. These results re-affirm the importance of the Hall term in allowing fast reconnection in the hybrid model.

  18. Training Top 10 Hall of Fame

    Science.gov (United States)

    Training, 2012

    2012-01-01

    Microsoft Corporation and SCC Soft Computer are the newest inductees into the Training Top 10 Hall of Fame, joining the ranks of the 11 companies named to the hall since its inception in 2008 (Wyeth Pharmaceuticals subsequently was acquired by Pfizer Inc. in 2009). These 11 companies held Top 10 spots in the Training Top 50, Top 100, and now Top…

  19. Fluctuations of a holographic quantum Hall fluid

    NARCIS (Netherlands)

    N. Jokela; M. Järvinen; M. Lippert

    2012-01-01

    We analyze the neutral spectrum of the holographic quantum Hall fluid de-scribed by the D2-D8’ model. As expected for a quantum Hall state, we find the system to be stable and gapped and that typically the lowest excitation mode is a magneto-roton. In addition, we find magneto-rotons in higher modes

  20. 19th Annual Residence Hall Construction Report

    Science.gov (United States)

    Agron, Joe

    2008-01-01

    The construction of residence hall facilities at colleges and universities continues to be strong, as institutions scramble to meet the housing needs and varied demands of a growing student population. This article presents data collected from 39 new residence hall projects completed in 2007. According to American School & University's 19th annual…

  1. Kelvin's Canonical Circulation Theorem in Hall Magnetohydrodynamics

    CERN Document Server

    Shivamoggi, B K

    2016-01-01

    The purpose of this paper is to show that, thanks to the restoration of the legitimate connection between the current density and the plasma flow velocity in Hall magnetohydrodynamics (MHD), Kelvin's Circulation Theorem becomes valid in Hall MHD. The ion-flow velocity in the usual circulation integral is now replaced by the canonical ion-flow velocity.

  2. Acoustical parameters in concert hall acoustics

    Institute of Scientific and Technical Information of China (English)

    LIU Ke; ZHOU Qijun

    2003-01-01

    Professor Beranek talked about the sound qualities of concert hall. The 58 famousconcert halls in the world were graded according to the subjective comparison from the profes-sional musicians and music lovers. Six measurable objective parameters were proposed. Theranking according to these parameters were presented.

  3. The Scientific Humanism of G. Stanley Hall

    Science.gov (United States)

    Meyer, Donald H.

    1971-01-01

    This paper presents the humanistic psychology of the pioneer American psychologist Granville Stanley Hall (1844-1924), examining Hall's effort to develop a system of psychology that is at once rigorously scientific and, simultaneously, capable of verifying essential human values. (Author)

  4. Metal-Film Hall-Effect Devices

    Science.gov (United States)

    Peters, Palmer N.

    1994-01-01

    Large positive and negative Hall coefficients achievable. Family of Hall-effect devices made from multilayer metal films instead of semiconductor materials. Metal films easier to fabricate; formed by deposition on variety of substrates, and leads readily attached to them. Fabricated with larger areas, potentially more reliable, and less affected by impurities. Also used to measure magnetic fields. Devices especially useful at low temperatures.

  5. A Holographic Quantum Hall Ferromagnet

    CERN Document Server

    Kristjansen, C; Semenoff, G W

    2013-01-01

    A detailed numerical study of a recent proposal for exotic states of the D3-probe D5 brane system with charge density and an external magnetic field is presented. The state has a large number of coincident D5 branes blowing up to a D7 brane in the presence of the worldvolume electric and magnetic fields which are necessary to construct the holographic state. Numerical solutions have shown that these states can compete with the the previously known chiral symmetry breaking and maximally symmetric phases of the D3-D5 system. Moreover, at integer filling fractions, they are incompressible with integer quantized Hall conductivities. In the dual superconformal defect field theory, these solutions correspond to states which break the chiral and global flavor symmetries spontaneously. The region of the temperature-density plane where the D7 brane has lower energy than the other known D5 brane solutions is identified. A hypothesis for the structure of states with filling fraction and Hall conductivity greater than on...

  6. Flexible Hall sensors based on graphene

    Science.gov (United States)

    Wang, Zhenxing; Shaygan, Mehrdad; Otto, Martin; Schall, Daniel; Neumaier, Daniel

    2016-03-01

    The excellent electronic and mechanical properties of graphene provide a perfect basis for high performance flexible electronic and sensor devices. Here, we present the fabrication and characterization of flexible graphene based Hall sensors. The Hall sensors are fabricated on 50 μm thick flexible Kapton foil using large scale graphene grown by chemical vapor deposition technique on copper foil. Voltage and current normalized sensitivities of up to 0.096 V VT-1 and 79 V AT-1 were measured, respectively. These values are comparable to the sensitivity of rigid silicon based Hall sensors and are the highest values reported so far for any flexible Hall sensor devices. The sensitivity of the Hall sensor shows no degradation after being bent to a minimum radius of 4 mm, which corresponds to a tensile strain of 0.6%, and after 1000 bending cycles to a radius of 5 mm.

  7. Thermoluminescence studies on γ-irradiated Mn:Li2B4O7 single crystals

    International Nuclear Information System (INIS)

    Manganese doped Li2B4O7 (LTB) crystals were grown by Czochralski technique and various kinetic parameter of thermoluminescence (TL) were measured. Crystals were irradiated with different γ-dose using Co60 source. Thermoluminescence curves were recorded at various heating rates. Trap depth and frequency factor were calculated. Fading of Mn: Li2B4O7 was found only ∼5%-6% in 6 months. Thermoluminescence intensity of Mn: Li2B4O7 was found highly sensitive to the mass of the material, and it varies abruptly with mass change of +/− 1 mg, irradiated with the same dose. Therefore, the accuracy in mass is important parameter for thermoluminescence dosimeter badge.

  8. Features of the electronic structure of the ternary superconductors RRh4B4 (R = Y, Lu)

    International Nuclear Information System (INIS)

    First-principles calculations of the electronic structure and a number of thermodynamical characteristics are performed for the ternary superconducting systems RRh4B4 (R = Y, Lu) in the normal state. The analysis of electronic states and their interactions responsible for superconducting and magnetic properties of the investigated systems is carried out. It is found that in YRh4B4 and LuRh4B4 compounds the Fermi level is situated in close proximity to a peak in the density of electronic states, and about 1 eV above of the pseudo-gap in the electronic spectrum. The existence of a number of groups of quasi-degenerate electronic states with a small effective mass near the Fermi level is revealed. These states can be the origin of a substantial conduction electrons diamagnetic contribution to the magnetic susceptibility, and can provide strong temperature dependences of the susceptibility in the rhodium borides.

  9. The design, fabrication and properties of B4C/Al neutron absorbers

    International Nuclear Information System (INIS)

    Neutron absorber is used for the criticality safety during the storage or transportation of spent nuclear fuel. In this work, the metal matrix composite with good mechanical property and thermal neutron absorbing ability was investigated based on B4C/Al neutron radiation shielding material. The composition ratio for B4C/Al composite was firstly designed and the dependence of the neutron transmission on the thickness of the material was calculated. By vacuum hot-pressing technique at a low temperature, the neutron absorbers with high concentration of B4C were fabricated. Furthermore, the corresponding microstructure, physical, mechanical and corrosion properties as well as fracture surface were analyzed, proving that the developed composites can shield the neutron radiation as effectively as cadmium materials

  10. Receptor protein tyrosine kinase EphB4 is up-regulated in colon cancer

    Directory of Open Access Journals (Sweden)

    Hewett Peter J

    2001-12-01

    Full Text Available Abstract Background We have used commercially available cDNA arrays to identify EphB4 as a gene that is up-regulated in colon cancer tissue when compared with matched normal tissue from the same patient. Results Quantitative RT-PCR analysis of the expression of the EphB4 gene has shown that its expression is increased in 82% of tumour samples when compared with the matched normal tissue from the same patient. Using immunohistochemistry and Western analysis techniques with an EphB4-specific antibody, we also show that this receptor is expressed in the epithelial cells of the tumour tissue and either not at all, or in only low levels, in the normal tissue. Conclusion The results presented here supports the emerging idea that Eph receptors play a role in tumour formation and suggests that further elucidation of this signalling pathway may identify useful targets for cancer treatment therapies.

  11. ErbB4 in Laminated Brain Structures: A Neurodevelopmental Approach to Schizophrenia

    Science.gov (United States)

    Perez-Garcia, Carlos G.

    2015-01-01

    The susceptibility genes for schizophrenia Neuregulin-1 (NRG1) and ErbB4 have critical functions during brain development and in the adult. Alterations in the ErbB4 signaling pathway cause a variety of neurodevelopmental defects including deficiencies in neuronal migration, synaptic plasticity, and myelination. I have used the ErbB4-/- HER4heart KO mice to study the neurodevelopmental insults associated to deficiencies in the NRG1-ErbB4 signaling pathway and their potential implication with brain disorders such as schizophrenia, a chronic psychiatric disease affecting 1% of the population worldwide. ErbB4 deletion results in an array of neurodevelopmental deficits that are consistent with a schizophrenic model. First, similar defects appear in multiple brain structures, from the cortex to the cerebellum. Second, these defects affect multiple aspects of brain development, from deficits in neuronal migration to impairments in excitatory/inhibitory systems, including reductions in brain volume, cortical and cerebellar heterotopias, alterations in number and distribution of specific subpopulations of interneurons, deficiencies in the astrocytic and oligodendrocytic lineages, and additional insults in major brain structures. This suggests that alterations in specific neurodevelopmental genes that play similar functions in multiple neuroanatomical structures might account for some of the symptomatology observed in schizophrenic patients, such as defects in cognition. ErbB4 mutation uncovers flaws in brain development that are compatible with a neurodevelopmental model of schizophrenia, and it establishes a comprehensive model to study the basis of the disorder before symptoms are detected in the adult. PMID:26733804

  12. ErbB4 in laminated brain structures: a neurodevelopmental approach to schizophrenia

    Directory of Open Access Journals (Sweden)

    Carlos Gustavo Perez-Garcia

    2015-12-01

    Full Text Available The susceptibility genes for schizophrenia Neuregulin-1 (NRG1 and ErbB4 have critical functions during brain development and in the adult. Alterations in the ErbB4 signaling pathway cause a variety of neurodevelopmental defects including deficiencies in neuronal migration, synaptic plasticity and myelination. I have used the ErbB4-/- HER4heart KO mice to study the neurodevelopmental insults associated to deficiencies in the NRG1-ErbB4 signaling pathway and their potential implication with brain disorders such as schizophrenia, a chronic psychiatric disease affecting 1% of the population worldwide. ErbB4 deletion results in an array of neurodevelopmental deficits that are consistent with a schizophrenic model. First, similar defects appear in multiple brain structures, from the cortex to the cerebellum. Second, these defects affect multiple aspects of brain development, from deficits in neuronal migration to impairments in excitatory/inhibitory systems, including reductions in brain volume, cortical and cerebellar heteropias, alterations in number and distribution of specific subpopulations of interneurons, deficiencies in the astrocytic and oligodendrocytic lineages, and additional insults in major brain structures. This suggests that alterations in specific neurodevelopmental genes that play similar functions in multiple neuroanatomical structures might account for some of the symptomatology observed in schizophrenic patients, such as defects in cognition. ErbB4 mutation uncovers flaws in brain development that are compatible with a neurodevelopmental model of schizophrenia, and it establishes a comprehensive model to study the basis of the disorder before symptoms are detected in the adult.

  13. 17 CFR 240.19b-4 - Filings with respect to proposed rule changes by self-regulatory organizations.

    Science.gov (United States)

    2010-04-01

    ... organizations. Preliminary Note: A self-regulatory organization also must refer to Form 19b-4 (17 CFR 249.819... paragraph (e), a self-regulatory organization shall submit Form 19b-4(e) (17 CFR 249.820) to the Commission... proposed rule changes by a self-regulatory organization submitted on Form 19b-4 (17 CFR...

  14. Leiomioma esofágico: Experiencia con diez casos operados en el "Hospital Dr. Rafael Ángel Calderón Guardia"

    Directory of Open Access Journals (Sweden)

    Giovanna Mainieri-Breedy

    2012-09-01

    Full Text Available Objetivo: informar la experiencia adquirida con la cirugía para leiomiomas esofágicos en el Servicio de Cirugía de Tórax del Hospital Dr. R. A. Calderón Guardia. Métodos: durante el período de 12 años comprendido entre 1999 y 2011, fueron referidos 14 pacientes con tumores submucosos del esófago al Servicio de Cirugía de Tórax del Hospital Calderón Guardia. En cuatro pacientes asintomáticos con tumores pequeños se decidió observar, y diez fueron operados, confirmándose el diagnóstico histológico de leiomioma. Previa autorización del Comité de Ética del Hospital, se revisaron los expedientes clínicos, analizando las características personales, los síntomas, los métodos de diagnóstico, el tratamiento quirúrgico y la evolución de los pacientes operados. Resultados: se encontró que de los diez pacientes operados, ocho fueron varones, en edades entre los 38 y 71 años, con un promedio de 56 años. El síntoma principal fue disfagia, pero en 3 casos el tumor fue un hallazgo incidental de una endoscopia de rutina. El método de detección en todos los casos fue la endoscopia en la que se describió un tumor submucoso o una compresión extrínseca de la pared esofágica. El ultrasonido endoscópico se correlacionó con un tumor originado en la cuarta capa, posible leiomioma. En dos casos, debido a las dimensiones de la lesión, se planteó la posibilidad de malignidad. La tumoración se intervino en nueve casos por toracotomía y en uno, por laparotomía. En 7 casos se enucleó sin que se abriera la mucosa, en dos se realizó esofagectomía parcial con anastomosis y parche de diafragma, y en un caso, excepcional, la tumoración se extendía desde el esófago cervical hasta la unión esófago-gástrica, de manera que se realizó una esofagectomía total, con ascenso gástrico y anastomosis cervical. No hubo ningún caso de mortalidad. Un paciente presentó una pequeña fuga de la anastomosis, la cual resolvió espont

  15. Molecular Model Design and Quantum Chemistry Calculation of Cluster B4N4

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The B4N4 configurations were designed by using the molecular figure software. The full geometry optimization and harmonic vibration frequency analysis were performed at the 6-31G(d) level using density functional theory B3LYP method, which indicates that the five isomers are stationary points on the potential energy surface of B4N4 molecules. The geometry structure, frontier molecular orbital (FMO) and mulliken population have been analyzed. The bonding properties and hybrid type were also discussed in detail, showing the addition of hydro- gen atoms to boron or nitrogen atom would increase the stabilities of the BN clusters.

  16. Short syntheses of enantiopure calystegine B-2, B-3, and B-4

    DEFF Research Database (Denmark)

    Skaanderup, Philip Robert; Madsen, Robert

    2001-01-01

    Calystegine B-2 B-3, and B-4 have been prepared in 5 steps from the benzyl protected methyl 6-iodoglycopyranosides of glucose, galactose and mannose, respectively, by using a zinc-mediated domino reaction followed by ring-closing olefin metathesis as the key steps.......Calystegine B-2 B-3, and B-4 have been prepared in 5 steps from the benzyl protected methyl 6-iodoglycopyranosides of glucose, galactose and mannose, respectively, by using a zinc-mediated domino reaction followed by ring-closing olefin metathesis as the key steps....

  17. Occurrence of Furnonisins B2 and B4 in Retail Raisins

    DEFF Research Database (Denmark)

    Knudsen, Peter Boldsen; Mogensen, Jesper Mølgaard; Larsen, Thomas Ostenfeld;

    2011-01-01

    -MS/MS survey of fumonisins in retail raisins. In 10 of 21 brands collected in Denmark, Germany, and The Netherlands, fumonisins B-2 and B-4 were detected at levels up to 13 and 1.3 mu g/kg, respectively. Only fumonisin B-2 has been detected in wine, so the presence of fumonisin B-4 in raisins suggests...... that the fumonisins are produced mainly during the drying process concomitant with the decreasing water activity. Analysis of multiple packages from one manufacturer showed a 3-fold package-to-package variation, suggesting that a few raisins per package are contaminated....

  18. Bronquiectasias, estudio de 36 pacientes intervenidos en el hospital “Dr. Rafael Ángel Calderón Guardia”

    Directory of Open Access Journals (Sweden)

    José Alberto Mainieri-Hidalgo

    2011-09-01

    Full Text Available Objetivo: Analizar el resultado de la cirugía por bronquiectasias en el Servicio de Cirugía de Tórax del Hospital Calderón Guardia. Método: Se revisaron los expedientes clínicos de 36 pacientes operados, con un total de 44 intervenciones por bronquiectasias. Resultados: Se encontró una prevalencia muy significativa de la enfermedad en mujeres, con una relación de 11 a 1. La etiología fue en 10 casos el antecedente de tuberculosis, en uno el síndrome de Kartagener, y en 25 no se logró establecer. Todos los pacientes tenían antecedente de tos y expectoración mucopurulenta de larga evolución, y 29 habían sido clasificados como asmáticos, aunque 10 no tenían ningún antecedente familiar. La radiografía de tórax fue anormal en todos los casos, mostrando áreas de fibrosis, infiltrados o nódulos, pero no fue útil para establecer el diagnóstico de bronquiectasias, contrario a la TAC, que en todos mostró las lesiones bronquiales. El resultado de la cirugía, contrario a lo esperado, no logró establecer un indicador de éxito, pues pacientes con lesiones muy localizadas continuaron expectorando e infectándose, y otros con patología difusa y bilateral, mejoraron sustancialmente. Conclusiones: La cirugía por bronquiectasias está indicada cuando el tratamiento médico no logra controlar satisfactoriamente los cuadros infecciosos bronquiales. Existe franca posibilidad de mejoría, pero no un indicador de éxito para el procedimiento quirúrgico.

  19. Bronquiectasias, estudio de 36 pacientes intervenidos en el hospital “Dr. Rafael Ángel Calderón Guardia” Bronchiectasis, Results of Surgical Intervention in 36 Patients

    OpenAIRE

    José Alberto Mainieri-Hidalgo

    2011-01-01

    Objetivo: Analizar el resultado de la cirugía por bronquiectasias en el Servicio de Cirugía de Tórax del Hospital Calderón Guardia. Método: Se revisaron los expedientes clínicos de 36 pacientes operados, con un total de 44 intervenciones por bronquiectasias. Resultados: Se encontró una prevalencia muy significativa de la enfermedad en mujeres, con una relación de 11 a 1. La etiología fue en 10 casos el antecedente de tuberculosis, en uno el síndrome de Kartagener, y en 25 no se logró establec...

  20. Sueño y mecanismos alegóricos en el auto de Calderón El tesoro escondido (1679): de la revelación a la epifanía

    OpenAIRE

    Gilbert, Françoise

    2011-01-01

    Para entender e interpretar el fenómeno del sueño en los autos de Calderón, es necesario establecer, desde un principio, una distinción fundamental entre las dos dimensiones semánticas del vocablo sueño, a saber el sueño como acto de dormir, que llamaremos «sueño-dormición» o sueño-somnus, y el sueño como acto de soñar, «sueño-ensueño» o sueño-somnium.

  1. Los sistemas de barrancos mexicanos, un recurso potencial para el turismo alternativo. El caso de los Barrancos del río Calderón, Estado de México

    OpenAIRE

    José Isabel Juan Pérez; José Francisco Monroy Gaytán; Jesús Gastón Gutiérrez Cedillo; Xanat Antonio Némiga; Miguel Ángel Balderas Plata

    2009-01-01

    El sistema de barrancos del río Calderón, ubicado al sureste del Estado de México,que comprende porciones de los municipios de Villa Guerrero, Ixtapan de La Sal y Zumpahuacán, representa un elemento geográfico de trascendencia para las familias de la región. En este lugar coexisten diversos ecosistemas con elementos geográficos, paisajísticos, geomorfológicos, hidrológicos y amplia biodiversidad que pueden ser utilizados para el turismo alternativo. Mediante el método geográfico, incluyendo c...

  2. Geometric Hall effects in topological insulator heterostructures

    Science.gov (United States)

    Yasuda, K.; Wakatsuki, R.; Morimoto, T.; Yoshimi, R.; Tsukazaki, A.; Takahashi, K. S.; Ezawa, M.; Kawasaki, M.; Nagaosa, N.; Tokura, Y.

    2016-06-01

    Geometry, both in momentum and in real space, plays an important role in the electronic dynamics of condensed matter systems. Among them, the Berry phase associated with nontrivial geometry can be an origin of the transverse motion of electrons, giving rise to various geometric effects such as the anomalous, spin and topological Hall effects. Here, we report two unconventional manifestations of Hall physics: a sign-reversal of the anomalous Hall effect, and the emergence of a topological Hall effect in magnetic/non-magnetic topological insulator heterostructures, Crx(Bi1-ySby)2-xTe3/(Bi1-ySby)2Te3. The sign-reversal in the anomalous Hall effect is driven by a Rashba splitting at the bulk bands, which is caused by the broken spatial inversion symmetry. Instead, the topological Hall effect arises in a wide temperature range below the Curie temperature, in a region where the magnetic-field dependence of the Hall resistance largely deviates from the magnetization. Its origin is assigned to the formation of a Néel-type skyrmion induced by the Dzyaloshinskii-Moriya interaction.

  3. Scintigraphic detection of pulmonary aspergillosis in rabbits with a radiolabeled leukotriene b4 antagonist.

    NARCIS (Netherlands)

    Eerd-Vismale, J.E.M. van; Rennen, H.J.J.M.; Oyen, W.J.G.; Harris, T.D.; Edwards, D.S.; Corstens, F.H.M.; Boerman, O.C.

    2004-01-01

    Radiolabeled chemotactic peptides have been studied for their applicability to the visualization of infectious and inflammatory foci. Because a radiolabeled leukotriene B4 (LTB4) antagonist allowed visualization of intramuscular E. coli abscesses in rabbits within a few hours after injection, we dec

  4. On the Potential of Interference Rejection Combining in B4G Networks

    DEFF Research Database (Denmark)

    Tavares, Fernando Menezes Leitão; Berardinelli, Gilberto; Mahmood, Nurul Huda;

    2013-01-01

    Beyond 4th Generation (B4G) local area networks will be characterized by the dense uncoordinated deployment of small cells. This paper shows that inter-cell interference, which is a main limiting factor in such networks, can be effectively contained using Interference Rejection Combining (IRC...

  5. Thermodynamic critical field of superconducting ErRh4B4 as a function of temperature

    International Nuclear Information System (INIS)

    Continuous magnetization curves for a polycrystalline specimen of ErRh4B4 are presented for a complete hysteresis cycle. A method is given to construct the diamagnetic contribution from the total magnetization curve. This method is used to obtain the values of the thermodynamic critical field Hsub(c) for the specimen as a function of temperature in the superconducting state. (author)

  6. Electrochemical Behavior of Al-B4C Metal Matrix Composites in NaCl Solution

    Directory of Open Access Journals (Sweden)

    Yu-Mei Han

    2015-09-01

    Full Text Available Aluminum based metal matrix composites (MMCs have received considerable attention in the automotive, aerospace and nuclear industries. One of the main challenges using Al-based MMCs is the influence of the reinforcement particles on the corrosion resistance. In the present study, the corrosion behavior of Al-B4C MMCs in a 3.5 wt.% NaCl solution were investigated using potentiodynamic polarization (PDP and electrochemical impedance spectroscopy (EIS techniques. Results indicated that the corrosion resistance of the composites decreased when increasing the B4C volume fraction. Al-B4C composite was susceptible to pitting corrosion and two types of pits were observed on the composite surface. The corrosion mechanism of the composite in the NaCl solution was primarily controlled by oxygen diffusion in the solution. In addition, the galvanic couples that formed between Al matrix and B4C particles could also be responsible for the lower corrosion resistance of the composites.

  7. Biodegradation of Benzo[a]pyrene by Arthrobacter oxydans B4

    Institute of Scientific and Technical Information of China (English)

    PENG Hui; YIN Hua; DENG Jun; YE Jin-Shao; CHEN Shuo-Na; HE Bao-Yan; ZHANG Na

    2012-01-01

    A bacterial strain,Arthrobacter oxydans (B4),capable of degrading benzo[a]pyrene (BaP) in water body,was isolated from a polycyclic aromatic hydrocarbons-contaminated site.Effects of different factors,such as reaction time,pH value,temperature and organic nutrients,on BaP biodegradation by the strain B4 were studied.After 5 d treatment,the concentration of BaP in mineral salts medium was reduced to 0.318 mg L-1,compared to the initial concentration of 1.000 mg L-1.There was a process of acid formation during the degradation with pH failing from initial 7.01 to 4.61 at 5 d,so keeping the water body under slightly alkaline condition was propitious to BaP degradation.Strain B4 efficiently degraded BaP at 20 to 37 ℃ with addition of organic nutrients.The biodegradation and transformation of BaP mainly occurred on cell surfaces,and extracellular secretions played an important role in these processes.Fourier transform infrared spectroscopy and gas chromatograph-mass spectrometer analyses of metabolites showed that ring cleavage occurred in the BaP degradation process and the resulting metabolically utilizable substrates were generated as sole carbon sources for B4 growth.Furthermore,mineralization extent of metabolites was verified by determining the total organic carbon and inorganic carbon in the degradation system.

  8. Tribological behavior of liquid metallurgy-processed AA 6061-B4C composites

    International Nuclear Information System (INIS)

    Aluminum metal matrix composites (AMMCs) possess improved properties compared to their monolithic counterparts and serve as a reliable alternative to replace them for applications that are considered as their niche. In the present investigation, 6061 Al alloy-10 wt% B4C composite is fabricated through liquid metallurgy stir casting technique and analyzed for its tribological characteristics. The uniform distribution of B4C reinforcement particles in the composite is achieved by the above route and is characterized using microstructure analysis and x-ray diffraction spectrum. The dry wear tests have been conducted under ambient conditions using a pin-on-disc tribometer. The worn surface and debris of the composite are also characterized using a scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDS). It is found that the combination of adhesion, delamination and abrasion constitute the predominant wear mechanism and this is influenced by the B4C particles, applied load, sliding distance and speed. The wear and friction coefficient increase with increase in applied load for all the load conditions studied. While the sliding speed fosters the engendering of a mechanically mixed layer (MML) to reduce the wear and friction coefficient, in contrast, the increase in sliding distance scuttles the MML formation owing to abrasion induced by the hard B4C particles. (paper)

  9. Podocyte EphB4 signaling helps recovery from glomerular injury.

    Science.gov (United States)

    Wnuk, Monika; Hlushchuk, Ruslan; Janot, Mathilde; Tuffin, Gérald; Martiny-Baron, Georg; Holzer, Philipp; Imbach-Weese, Patricia; Djonov, Valentin; Huynh-Do, Uyen

    2012-06-01

    Eph receptor tyrosine kinases and their ligands (ephrins) have a pivotal role in the homeostasis of many adult organs and are widely expressed in the kidney. Glomerular diseases beginning with mesangiolysis can recover, with podocytes having a critical role in this healing process. We studied here the role of Eph signaling in glomerular disease recovery following mesangiolytic Thy1.1 nephritis in rats. EphB4 and ephrinBs were expressed in healthy glomerular podocytes and were upregulated during Thy1.1 nephritis, with EphB4 strongly phosphorylated around day 9. Treatment with NPV-BHG712, an inhibitor of EphB4 phosphorylation, did not cause glomerular changes in control animals. Nephritic animals treated with vehicle did not have morphological evidence of podocyte injury or loss; however, application of this inhibitor to nephritic rats induced glomerular microaneurysms, podocyte damage, and loss. Prolonged NPV-BHG712 treatment resulted in increased albuminuria and dysregulated mesangial recovery. Additionally, NPV-BHG712 inhibited capillary repair by intussusceptive angiogenesis (an alternative to sprouting angiogenesis), indicating a previously unrecognized role of podocytes in regulating intussusceptive vessel splitting. Thus, our results identify EphB4 signaling as a pathway allowing podocytes to survive transient capillary collapse during glomerular disease.

  10. Fatigue failure of micro-alloyed 23MnB4 steel

    Directory of Open Access Journals (Sweden)

    S. Rusz

    2008-12-01

    Full Text Available Purpose: In the following paper there have been the structure and fatigue properties of micro-alloyed 23MnB4 steel in initial state and after heat treatment evaluated.Design/methodology/approach: Fatigue test of micro-alloyed 23MnB4 steel was completed by metallographic and fracture analyses. For scope the methods of the light microscopy and SEM were used.Findings: Microstructure of examined alloy in initial state was characterized mostly by fine ferrite with pearlitic net and in state after heat treatment was formed by martensite or partly by bainite and after tempering was formed by tempered martensite. Objective of this work consisted in determination of fatigue characteristics of micro-alloyed 23MnB4 steel, including fracture analyze. Results of fatigue testing at various stress levels for the samples in initial state and after the heat treatment have confirmed that obtained values of cycles to rupture were at least 585 000 cycles. Change of fatigue properties in dependence on heat treatment of the used steel.Research limitations/implications: For define fracture area a samples must be provide with notch. The experiment was limited by occurrence a void in cast alloys.Practical implications: The results may be utilized for application of the investigated material in process of manufacturing.Originality/value: These results contribute to explanation of fracture mechanism of micro-alloyed 23MnB4 steel.

  11. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  12. Piezo Voltage Controlled Planar Hall Effect Devices.

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-01-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  13. Piezo Voltage Controlled Planar Hall Effect Devices

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K. W.; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  14. Anomalous Hall effect for semiclassical chiral fermions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengming, E-mail: zhpm@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Horváthy, P.A., E-mail: horvathy@lmpt.univ-tours.fr [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou (China); Laboratoire de Mathématiques et de Physique Théorique, Université de Tours (France)

    2015-03-06

    Semiclassical chiral fermions manifest the anomalous spin-Hall effect: when put into a pure electric field they suffer a side jump, analogous to what happens to their massive counterparts in non-commutative mechanics. The transverse shift is consistent with the conservation of the angular momentum. In a pure magnetic field, instead, spiraling motion is found. Motion in Hall-type perpendicular electric and magnetic fields is also studied. - Highlights: • Chiral fermions exhibit an anomalous spin-Hall effect. • Transverse shift appears in a pure electric field. • In a pure magnetic field spiraling motion is found.

  15. Joule heating in spin Hall geometry

    Science.gov (United States)

    Taniguchi, Tomohiro

    2016-07-01

    The theoretical formula for the entropy production rate in the presence of spin current is derived using the spin-dependent transport equation and thermodynamics. This theory is applicable regardless of the source of the spin current, for example, an electric field, a temperature gradient, or the Hall effect. It reproduces the result in a previous work on the dissipation formula when the relaxation time approximation is applied to the spin relaxation rate. By using the developed theory, it is found that the dissipation in the spin Hall geometry has a contribution proportional to the square of the spin Hall angle.

  16. Decommissioning of the Salaspils Research Reactor

    Directory of Open Access Journals (Sweden)

    Abramenkovs Andris

    2011-01-01

    Full Text Available In May 1995, the Latvian government decided to shut down the Salaspils Research Reactor and to dispense with nuclear energy in the future. The reactor has been out of operation since July 1998. A conceptual study on the decommissioning of the Salaspils Research Reactor was drawn up by Noell-KRC-Energie- und Umwelttechnik GmbH in 1998-1999. On October 26th, 1999, the Latvian government decided to start the direct dismantling to “green-field” in 2001. The upgrading of the decommissioning and dismantling plan was carried out from 2003-2004, resulting in a change of the primary goal of decommissioning. Collecting and conditioning of “historical” radioactive wastes from different storages outside and inside the reactor hall became the primary goal. All radioactive materials (more than 96 tons were conditioned for disposal in concrete containers at the radioactive wastes depository “Radons” at the Baldone site. Protective and radiation measurement equipment of the personnel was upgraded significantly. All non-radioactive equipment and materials outside the reactor buildings were released for clearance and dismantled for reuse or conventional disposal. Contaminated materials from the reactor hall were collected and removed for clearance measurements on a weekly basis.

  17. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  18. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  19. Spin Hall effect, Hall effect and spin precession in diffusive normal metals

    OpenAIRE

    Shchelushkin, R. V.; Brataas, Arne

    2005-01-01

    We study transport in normal metals in an external magnetic field. This system exhibits an interplay between a transverse spin imbalance (spin Hall effect) caused by the spin-orbit interaction, a Hall effect via the Lorentz force, and spin precession due to the Zeeman effect. Diffusion equations for spin and charge flow are derived. The spin and charge accumulations are computed numerically in experimentally relevant thin film geometries. The out-of-plane spin Hall potential is suppressed whe...

  20. Homogenization of the three-dimensional Hall effect and change of sign of the Hall coefficient

    OpenAIRE

    Briane, Marc; Milton, Graeme W.

    2009-01-01

    17 pages, 4 figures International audience The notion of a Hall matrix, associated with a possibly anisotropic conducting material in the presence of a small magnetic field, is introduced. Then, for any material having a microstructure we prove a general homogenization result satisfied by the Hall matrix in the framework of the H-convergence of Murat-Tartar. Extending a result of Bergman, it is shown that the Hall matrix can be computed from the corrector associated with the homogenizat...

  1. Topologically induced fractional Hall steps in the integer quantum Hall regime of MoS 2.

    Science.gov (United States)

    Islam, S K Firoz; Benjamin, Colin

    2016-09-23

    The quantum magnetotransport properties of a monolayer of molybdenum disulfide are derived using linear response theory. In particular, the effect of topological terms on longitudinal and Hall conductivity is analyzed. The Hall conductivity exhibits fractional steps in the integer quantum Hall regime. Further complete spin and valley polarization of the longitudinal conductivitity is seen in presence of these topological terms. Finally, the Shubnikov-de Hass oscillations are suppressed or enhanced contingent on the sign of these topological terms. PMID:27533362

  2. Crossover of the Hall-voltage distribution in AC quantum Hall effect

    OpenAIRE

    Akera, H.

    2011-01-01

    The distribution of the Hall voltage induced by low-frequency AC current is studied theoretically in the incoherent linear transport of quantum Hall systems. It is shown that the Hall-voltage distribution makes a crossover from the uniform distribution to a concentrated-near-edges distribution as the frequency is increased or the diagonal conductivity is decreased. This crossover is also reflected in the frequency dependence of AC magnetoresistance.

  3. Crossover of the Hall-voltage distribution in AC quantum Hall effect

    OpenAIRE

    Akera, Hiroshi

    2009-01-01

    The distribution of the Hall voltage induced by low-frequency AC current is studied theoretically in the incoherent linear transport of quantum Hall systems. It is shown that the Hall-voltage distribution makes a crossover from the uniform distribution to a concentrated-near-edges distribution as the frequency is increased or the diagonal conductivity is decreased. This crossover is also reflected in the frequency dependence of AC magnetoresistance.

  4. Intrinsic spin Hall effect in silicene: transition from spin Hall to normal insulator

    OpenAIRE

    Dyrdal, A.; Barnas, J.

    2012-01-01

    Intrinsic contribution to the spin Hall effect in a two-dimensional silicene is considered theoretically within the linear response theory and Green function formalism. When an external voltage normal to the silicene plane is applied, the spin Hall conductivity is shown to reveal a transition from the spin Hall insulator phase at low voltages to the conventional insulator phase at higher voltages. This transition resembles recently reported phase transition in a bilayer graphene. The spin-orb...

  5. Topologically induced fractional Hall steps in the integer quantum Hall regime of MoS 2

    Science.gov (United States)

    Firoz Islam, SK; Benjamin, Colin

    2016-09-01

    The quantum magnetotransport properties of a monolayer of molybdenum disulfide are derived using linear response theory. In particular, the effect of topological terms on longitudinal and Hall conductivity is analyzed. The Hall conductivity exhibits fractional steps in the integer quantum Hall regime. Further complete spin and valley polarization of the longitudinal conductivitity is seen in presence of these topological terms. Finally, the Shubnikov-de Hass oscillations are suppressed or enhanced contingent on the sign of these topological terms.

  6. Quantum spin Hall effect in 2D topological insulators

    OpenAIRE

    Sonin, E. B.

    2011-01-01

    The original motivation of great interest to topological insulators was the hope to observe the quantum spin Hall effect. Therefore if a material is in the topological insulator state they frequently call it the quantum spin Hall state. However, despite impressive experimental results confirming the existence of the quantum spin Hall state, the quantum spin Hall effect has not yet been detected. After a short overview of what was originally suggested as the quantum spin Hall effect (quantum s...

  7. 以聚碳硅烷包覆B4C为原料温压-烧结原位制备SiC/B4C复相陶瓷%SiC/B4C Multiphase Ceramics Using Polycarbosilane-Coating B4C as Raw Materials Prepared In-suit by Warm Pressing and Sintering

    Institute of Scientific and Technical Information of China (English)

    林文松; 何亮

    2011-01-01

    B4 C/SiC pellets were prepared by warm pressing of polycarbosilane-coating boron carbide powder at the temperature of 300 ℃ under the pressure of 50 Mpa, and cold isostatic pressing under the pressure of 800 Mpa, respectively. The samples were then kept warm at 1 200 ℃ for 2 h in flowing Ar, with subsequent sintering for 3 h between 1 800 and 2 000 ℃ in vacuum. Relative densities, phases and microstructures of the multiphase ceramics were investigated. The results show that the multiphase ceramics prepared by warm pressing (WP) had higher density than that by cold isostatic pressing (CIP). The multiphase ceramics with maximum relative density was achieved after the warm pressing green bodies containing 15% SiC sintered for 3 h, and its relative density was more than 93%. The multiphase ceramics consisted of B4C and SiC and SiC phases distributed uniformly on the B1C particles interface.%以聚碳硅烷(PCS)包覆B4C粉为原料,分别在300℃、50 MPa下温压成型和800MPa下冷等静压成型,而后将压坯置于氩气气氛保护下在1 200℃保温2 h,再在1 800~2 000℃下真空烧结3 h,原位反应制备出SiC/B4C复相陶瓷;研究了它的相对密度、物相组成和显微结构。结果表明:温压工艺比冷等静压工艺能得到更高密度的复相陶瓷;合15%SoC的温压压坯在烧结3 h后得到复相陶瓷的相对密度大于93%;复相陶瓷由B4C和SiC相组成,SiC相均匀分布在B4C颗粒界面上。

  8. Two LHC dipole magnets in assembly hall

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    The final LHC components are completed in the assembly hall, prior to installation in the tunnel. These pictures show two 15-m long LHC cryogenic magnets, both before and after insertion into their blue vacuum vessel.

  9. Multiscale Modeling of Hall Thrusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — New multiscale modeling capability for analyzing advanced Hall thrusters is proposed. This technology offers NASA the ability to reduce development effort of new...

  10. Iodine Hall Thruster for Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the Phase I program, Busek Co. Inc. tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high flow iodine feed system,...

  11. The phonon Hall effect: theory and application

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lifa; Wang Jiansheng; Li Baowen [Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117542 (Singapore); Ren Jie [NUS Graduate School for Integrative Sciences and Engineering, Singapore 117456 (Singapore)

    2011-08-03

    We present a systematic theory of the phonon Hall effect in a ballistic crystal lattice system, and apply it on the kagome lattice which is ubiquitous in various real materials. By proposing a proper second quantization for the non-Hermitian in the polarization-vector space, we obtain a new heat current density operator with two separate contributions: the normal velocity responsible for the longitudinal phonon transport, and the anomalous velocity manifesting itself as the Hall effect of transverse phonon transport. As exemplified in kagome lattices, our theory predicts that the direction of Hall conductivity at low magnetic field can be reversed by tuning the temperatures, which we hope can be verified by experiments in the future. Three phonon-Hall-conductivity singularities induced by phonon-band-topology change are discovered as well, which correspond to the degeneracies at three different symmetric center points, {Gamma}, K, X, in the wavevector space of the kagome lattice.

  12. Magnetic measurements at 'GANIL' - Hall probe utilization

    International Nuclear Information System (INIS)

    This work was intended for developing a magnetic field measuring bench, and for investigating the various methods of magnetic measurements capable to answer the requirements from GANIL users: NMR, magnetoresistance, Hall probes, rotating coils. Two methods only are shown to fulfill the requirements from GANIL users: the Hall probe measuring method, and the method of the rotating coils. A great advantage of the Hall probe method is due to the simpleness of its electronic equipment, and the possibility of measuring fields with sharp variations in time, in view of the short response time of Hall effect. The method is most suitable for azimuthal measurements and determining heterogeneities in the magnetic field. A prevailing advantage of the rotating coil method is its linearity due to the direct read-out of the magnetic field with using a single constant over the whole range of measurement. The method is most suitable for field differential measurements

  13. The Assembly Hall in Lab II

    CERN Multimedia

    1974-01-01

    Magnets and components of all types for the SPS were delivered and stored in this hall during 1974. There also took place the testing, assembly and final preparation of components to be installed in the ring tunnel.

  14. Light Metal Propellant Hall Thruster Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek proposes to develop light metal Hall Effect thrusters that will help reduce the travel time, mass, and cost of SMD spacecraft. Busek has identified three...

  15. Dual Mode Low Power Hall Thruster Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sample and return missions desire and missions like Saturn Observer require a low power Hall thruster that can operate at high thrust to power as well as high...

  16. Boundary Effective Action for Quantum Hall States

    Science.gov (United States)

    Gromov, Andrey; Jensen, Kristan; Abanov, Alexander G.

    2016-03-01

    We consider quantum Hall states on a space with boundary, focusing on the aspects of the edge physics which are completely determined by the symmetries of the problem. There are four distinct terms of Chern-Simons type that appear in the low-energy effective action of the state. Two of these protect gapless edge modes. They describe Hall conductance and, with some provisions, thermal Hall conductance. The remaining two, including the Wen-Zee term, which contributes to the Hall viscosity, do not protect gapless edge modes but are instead related to the local boundary response fixed by symmetries. We highlight some basic features of this response. It follows that the coefficient of the Wen-Zee term can change across an interface without closing a gap or breaking a symmetry.

  17. Well-posedness for Hall-magnetohydrodynamics

    OpenAIRE

    Chae, Dongho; Degond, Pierre; Liu, Jian-guo

    2012-01-01

    We prove local existence of smooth solutions for large data and global smooth solutions for small data to the incompressible, resitive, viscous or inviscid Hall-MHD model. We also show a Liouville theorem for the stationary solutions.

  18. Elementary theory of quantum Hall effect

    Directory of Open Access Journals (Sweden)

    Keshav N. Shrivastava

    2008-04-01

    Full Text Available The Hall effect is the generation of a current perpendicular to both the direction of the applied electric as well as magnetic field in a metal or in a semiconductor. It is used to determine the concentration of electrons. The quantum Hall effect with integer quantization was discovered by von Klitzing and fractionally charged states were found by Tsui, Stormer and Gossard. Robert Laughlin explained the quantization of Hall current by using “flux quantization” and introduced incompressibility to obtain the fractional charge. We have developed the theory of the quantum Hall effect by using the theory of angular momentum. Our predicted fractions are in accord with those measured. We emphasize our explanation of the observed phenomena. We use spin to explain the fractional charge and hence we discover spin-charge locking.

  19. Quantum anomalous Hall effect with higher plateaus.

    Science.gov (United States)

    Wang, Jing; Lian, Biao; Zhang, Haijun; Xu, Yong; Zhang, Shou-Cheng

    2013-09-27

    The quantum anomalous Hall (QAH) effect in magnetic topological insulators is driven by the combination of spontaneous magnetic moments and spin-orbit coupling. Its recent experimental discovery raises the question if higher plateaus can also be realized. Here, we present a general theory for a QAH effect with higher Chern numbers and show by first-principles calculations that a thin film magnetic topological insulator of Cr-doped Bi2(Se,Te)3 is a candidate for the C=2 QAH insulator. Remarkably, whereas a higher magnetic field leads to lower Hall conductance plateaus in the integer quantum Hall effect, a higher magnetic moment leads to higher Hall conductance plateaus in the QAH effect.

  20. Iodine Hall Thruster for Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek Co. Inc. proposes to develop a high power (high thrust) electric propulsion system featuring an iodine fueled Hall Effect Thruster (HET). The system to be...

  1. Topological Hall Effect in Inhomogeneous Superconductors

    OpenAIRE

    Fujimoto, Satoshi

    2010-01-01

    We propose a possible mechanism of topological Hall effect in inhomogeneous superconducting states. In our scenario, the Berry phase effect associated with spatially modulated superconducting order parameter gives rise to a fictitious Lorentz force acting on quasiparticles. In the case of the Fulde-Ferrell-Larkin-Ovchinnikov state, the topological Hall effect is detected by applying an electromagnetic wave with a tuned wave number on a surface of the system.

  2. The mathematics of lecture hall partitions

    OpenAIRE

    Savage, Carla D.

    2016-01-01

    Over the past twenty years, lecture hall partitions have emerged as fundamental combinatorial structures, leading to new generalizations and interpretations of classical theorems and new results. In recent years, geometric approaches to lecture hall partitions have used polyhedral geometry to discover further properties of these rich combinatorial objects. In this paper we give an overview of some of the surprising connections that have surfaced in the process of trying to understand the lect...

  3. Piezo Voltage Controlled Planar Hall Effect Devices

    OpenAIRE

    Bao Zhang; Kang-Kang Meng; Mei-Yin Yang; Edmonds, K. W.; Hao Zhang; Kai-Ming Cai; Yu Sheng; Nan Zhang; Yang Ji; Jian-Hua Zhao; Hou-Zhi Zheng; Kai-You Wang

    2016-01-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the pie...

  4. Observation of a superfluid Hall effect

    OpenAIRE

    LeBlanc, Lindsay J.; Jiménez-García, Karina; Williams, Ross A.; Beeler, Matthew C.; Perry, Abigail R.; Phillips, William D.; Spielman, Ian B.

    2012-01-01

    Measurement techniques based upon the Hall effect are invaluable tools in condensed matter physics. When an electric current flows perpendicular to a magnetic field, a Hall voltage develops in the direction transverse to both the current and the field. In semiconductors, this behaviour is routinely used to measure the density and charge of the current carriers (electrons in conduction bands or holes in valence bands) -- internal properties of the system that are not accessible from measuremen...

  5. Strongly Correlated Fractional Quantum Hall Line Junctions

    OpenAIRE

    Zuelicke, U.; Shimshoni, E.

    2002-01-01

    We have studied a clean finite-length line junction between interacting counterpropagating single-branch fractional-quantum-Hall edge channels. Exact solutions for low-lying excitations and transport properties are obtained when the two edges belong to quantum Hall systems with different filling factors and interact via the long-range Coulomb interaction. Charging effects due to the coupling to external edge-channel leads are fully taken into account. Conductances and power laws in the curren...

  6. Book review: Land by Derek Hall

    OpenAIRE

    Wilcox, Susannah

    2013-01-01

    Land is one of the world’s most emotionally resonant resources, and control over it is fundamental to almost all human activity. In Land, Derek Hall develops a framework for understanding the geopolitics of land today. Drawing on a wide range of cases and examples – from the Afghanistan–Pakistan border to the Canadian Arctic, China’s urban fringe to rural Honduras – Hall provides an enlightening glimpse into the many conceptual, empirical, financial, political and emotional struggles around l...

  7. An introduction to motivic Hall algebras

    CERN Document Server

    Bridgeland, Tom

    2010-01-01

    We give an introduction to Joyce's construction of the motivic Hall algebra of coherent sheaves on a variety M. When M is a Calabi-Yau threefold we define a semi-classical integration map from a Poisson subalgebra of this Hall algebra to the ring of functions on a symplectic torus. This material will be used in arxiv:1002.4374 to prove some basic properties of Donaldson-Thomas curve-counting invariants on Calabi-Yau threefolds.

  8. Energy magnetization and the thermal Hall effect.

    Science.gov (United States)

    Qin, Tao; Niu, Qian; Shi, Junren

    2011-12-01

    We obtain a set of general formulas for determining magnetizations, including the usual electromagnetic magnetization as well as the gravitomagnetic energy magnetization. The magnetization corrections to the thermal transport coefficients are explicitly demonstrated. Our theory provides a systematic approach for properly evaluating the thermal transport coefficients of magnetic systems, eliminating the unphysical divergence from the direct application of the Kubo formula. For a noninteracting anomalous Hall system, the corrected thermal Hall conductivity obeys the Wiedemann-Franz law.

  9. Zn(1,3-DAP)[B4O7]: a rare chiral zeolitic framework constructed of four-connected [B4O9] clusters with a single-stranded helical channel.

    Science.gov (United States)

    Pan, Chun-Yang; Zhong, Li-Juan; Zhao, Feng-Hua; Yang, Hong-Mei; Zhou, Jian

    2015-01-14

    A zinc borate Zn(1,3-DAP)[B4O7] (1) was prepared. 1 was revealed to be a rare chiral zeolitic framework based on a [B4O9] cluster. The combination of a [B4O9] cluster and Zn(1,3-DAP)O3 chain produced a helical ribbon motif and gave rise to a single-stranded helical channel. PMID:25421529

  10. Trombosis de senos durales: casuística del Hospital Dr. Rafael Angel Calderón Guardia, período 1996-1999

    Directory of Open Access Journals (Sweden)

    Kwok Ho Sánchez-Suen

    2001-10-01

    Full Text Available Justificación: La oclusión trombótica de las venas cerebrales o senos durales es una causa menos frecuente de enfermedad cerebrovascular que la trombosis arterial. Sin embargo; los estudios epidemiológicos indican que esta entidad no es tan inusual como o ser pensaba previamente. Hasta donde sabemos, no hay ningún estudio publicando al respecto en la literatura nacional, siendo precisamente el motivo del presente trabajo. Objetivos: Identificar las características demográficas, clínicas y diagnósticas de los pacientes que sufrieron una trombosis de senos venosos durales. Describir los métodos terapéuticos empleados y la evolución que tuvieron estos pacientes. Materiales y métodos: Se revisaron los expedientes clínicos de 11 casos diagnosticados de trombosis de senos durales en el Hospital Dr. Rafael Ángel Calderón Guardia, en el período comprendido entre enero de 1996 a enero de 1999. Se analizaron los posibles factores de riego, formas de presentación clínica, estudios de radio imagen y tratamiento empleado. Resultados: El promedio de edad fue de 32,6 años. Un 18,2% fueron varones, mientras que el 81,8% correspondió a mujeres. Las manifestaciones más frecuentes fueron: cefalea (100%, vómito (91%, déficit motor 882%, alteración del sensorio (73%, papiledema (54,5%, crisis convulsiva (54,5% y datos de irritación meníngea (36,4%: el signo del delta vacío se documentó en 27,3% de los estudios tomográficos. El seno sagital superior fue el más frecuentemente afectado (91%. Se anticoaguló con heparina intravenosa al 54, 5% de los casos. Conclusiones: Aunque somos conscientes de las limitaciones de nuestra serie, nuestra intención ha sido llamar la atención sobre una patología vascular cerebral, que aunque no es tan frecuente como su contraparte arterial, debe tenerse en consideración por sus potenciales efectos sobre la salud del paciente. El conocimiento adecuado de esta condición es importante, debido a que a

  11. Características del control prenatal y el parto de las mujeres inmigrantes atendidas en el Hospital "Dr. Rafael Ángel Calderón Guardia"

    Directory of Open Access Journals (Sweden)

    Manrique Leal-Mateos

    2008-06-01

    Full Text Available Justificación y objetivo: El presente estudio tiene como objetivo principal dar a conocer las características más sobresalientes del control prenatal y del parto de la población inmigrante que acude al Servicio de Obstetricia del Hospital Dr. Rafael A. Calderón Guardia, Costa Rica y comparar los resultados obtenidos con los observados en la población costarricense, con el fin de determinar si difieren entre sí. Materiales y métodos: Se realizó un estudio observacional analítico de corte transversal. Mediante un muestreo consecutivo se analizaron 360 historias clínicas de pacientes gestantes atendidas en HCG entre el 1 de agosto y 7 de septiembre de 2007. Se excluyó del análisis toda paciente que no perteneciera al área de atracción del HCG o que presentara de forma incompleta alguna de las variables de interés. La recolección de la información se realizó mediante una hoja precodificada diseñada con base la que se utiliza para el control prenatal en el sistema de salud nacional. Resultados: Aproximadamente una de cada 5 pacientes embarazadas que dan a luz en el HCG son inmigrantes. La mayor parte de ellas son de origen nicaragüense, relativamente jóvenes, multíparas y con controles prenatales adecuados. Además, presentan una morbilidad previa e inducida por el embarazo semejante a la encontrada en las gestantes nacionales. Si bien aproximadamente la mitad de las pacientes inmigrantes se captan de forma tardía y presentan una cantidad menor de consultas prenatales a la observada en las embarazadas costarricenses, este aspecto no parece influir en los resultados derivados de la atención de su parto ni en las características de los recién nacidos al momento de su nacimiento. Conclusión: Las características de la población inmigrante que da a luz en el Hospital no son diferentes a las encontradas en las mujeres costarricenses.

  12. Antenatal and Postnatal Diagnosis of Coxsackie B4 Infection: Case Series

    Directory of Open Access Journals (Sweden)

    Jennifer C. Hunt

    2012-11-01

    Full Text Available Enteroviruses are a common cause of neonatal infection. In particular, Coxsackie B viruses are often associated with severe, fatal disease. The antenatal diagnosis of Coxsackie B viral infections is uncommon. We present a unique case of Coxsackie B4 virus ventriculitis and myocarditis causing fetal hydrops at 22 weeks gestation. Transmission was inferred by viral isolation from the amniotic fluid and by placental pathology. We also describe two additional cases of fatal neonatal Coxsackie B4 infection complicated by myocarditis and encephalitis with cerebral necrosis in a 4-day-old female and by myocarditis, spinal leptomeningitis, and hepatitis in a 4-day-old male. Transplacental acquisition of infection carries a poor prognosis. We propose that Coxsackie B virus should be considered in the investigation of nonimmune hydrops, particularly in the presence of cardiac dysfunction.

  13. Antenatal and postnatal diagnosis of coxsackie b4 infection: case series.

    Science.gov (United States)

    Hunt, Jennifer C; Schneider, Carol; Menticoglou, Savas; Herath, Jayantha; Del Bigio, Marc R

    2012-11-01

    Enteroviruses are a common cause of neonatal infection. In particular, Coxsackie B viruses are often associated with severe, fatal disease. The antenatal diagnosis of Coxsackie B viral infections is uncommon. We present a unique case of Coxsackie B4 virus ventriculitis and myocarditis causing fetal hydrops at 22 weeks gestation. Transmission was inferred by viral isolation from the amniotic fluid and by placental pathology. We also describe two additional cases of fatal neonatal Coxsackie B4 infection complicated by myocarditis and encephalitis with cerebral necrosis in a 4-day-old female and by myocarditis, spinal leptomeningitis, and hepatitis in a 4-day-old male. Transplacental acquisition of infection carries a poor prognosis. We propose that Coxsackie B virus should be considered in the investigation of nonimmune hydrops, particularly in the presence of cardiac dysfunction. PMID:23946895

  14. Determination of Optimum Cutting Parameters for Surface Roughness in Turning AL-B4C Composites

    Science.gov (United States)

    Channabasavaraja, H. K.; Nagaraj, P. M.; Srinivasan, D.

    2016-09-01

    Many materials such as alloys, composites find their applications on the basis of machinability, cost and availability. In the present work, machinability of Aluminium 1100 and Boron carbide (AL+ B4C) composite material is examined by using lathe tool dynometers (BANKA Lathe) by varying the cutting parameters like spindle speed, Depth of cut and Feed rate in 3 levels. Also, surface roughness is measured against the weight % of reinforcement in the composite (0, 4 and 8 %). From the study it is observed that the hardness of a composite material increases with increase in weight % of reinforcement material (B4C) by 26.27 and 66.7 % respectively. The addition of reinforcement materials influences the machinability. The cutting force in both X and Z direction were also found increment with the reinforcement percentage.

  15. Consolidation of B4C-TaB2 eutectic composites by spark plasma sintering

    OpenAIRE

    Dmytro Demirskyi

    2015-01-01

    The in situ synthesis/consolidation of B4C-TaB2 eutectic composites by spark plasma sintering (SPS) is reported. The microstructure–property relations were determined for composites with the B4C-TaB2 eutectic composition as functions of TaB2 content, and TaB2-TaB2 interlamellar spacing. A clear maximum in fracture toughness was identified (∼4.5 MPa m1/2) for eutectic composites with interlamellar spacing between 0.9 and 1.1 μm. The composites with the hypereutectic composition of 40 mol.% TaB...

  16. Cr/B4C multilayer mirrors: Study of interfaces and X-ray reflectance

    Science.gov (United States)

    Burcklen, C.; Soufli, R.; Dennetiere, D.; Polack, F.; Capitanio, B.; Gullikson, E.; Meltchakov, E.; Thomasset, M.; Jérome, A.; de Rossi, S.; Delmotte, F.

    2016-03-01

    We present an experimental study of the effect of layer interfaces on the x-ray reflectance in Cr/B4C multilayer interference coatings with layer thicknesses ranging from 0.7 nm to 5.4 nm. The multilayers were deposited by magnetron sputtering and by ion beam sputtering. Grazing incidence x-ray reflectometry, soft x-ray reflectometry, and transmission electron microscopy reveal asymmetric multilayer structures with a larger B4C-on-Cr interface, which we modeled with a 1-1.5 nm thick interfacial layer. Reflectance measurements in the vicinity of the Cr L2,3 absorption edge demonstrate fine structure that is not predicted by simulations using the currently tabulated refractive index (optical constants) values for Cr.

  17. Optimization Conditions of Production Fibrinolytic Enzyme from Bacillus lichniformis B4 Local Isolate

    OpenAIRE

    Essam F. Al-Juamily; Bushra H. Al-Zaidy

    2012-01-01

    The study was conducted with the aim to found local isolate belongs to Bacillus lichniformis to produce fibrinolytic enzyme with highest activity under optimal conditions. Forty-five local isolates belongs to the genus Bacillus lichniformis were selected for production of fibrinolytic enzyme (E.C. 3.4.). The isolate Bacillus lichniformis B4 was selected due to its high productivity of fibrinolytic enzyme. The optimal conditions for fibrinolytic enzyme production were determined, using a solid...

  18. Acute transverse myelitis caused by Coxsackie virus B4 infection: a case report.

    OpenAIRE

    Ku, B; Lee, K.

    1998-01-01

    Acute transverse myelitis is a rare clinical manifestation of Coxsackie virus infection which cause acute and progressive debilitating illness associated with loss of spinal cord function in the affected patients. A 62 year-old female developed symptoms of rapidly progressive paraplegia with sensory loss. On spinal MRI, T2 sagittal image showed increased signal intensity with cord swelling at T11-L2 level and 8 folds or greater rise of Coxsackie virus B4 neutralizing antibody titers was obser...

  19. Experimental determination of magnetic Landau parameters in ErRh4B4

    International Nuclear Information System (INIS)

    From d.c. magnetization data obtained between 0.45 and 13 K the following are derived: the bare Curie temperature, the temperature dependence of the paramagnetic susceptibility, and the coefficients of the higher order terms in the Landau expansion of the magnetic free energy for ErRh4B4. It is found that the fourth order term is small or zero. Consequently the sixth order term plays the dominant role in stabilizing the magnetic phase. (author)

  20. ∆DNMT3B4-del Contributes to Aberrant DNA Methylation Patterns in Lung Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Mark Z. Ma

    2015-10-01

    Full Text Available Aberrant DNA methylation is a hallmark of cancer but mechanisms contributing to the abnormality remain elusive. We have previously shown that ∆DNMT3B is the predominantly expressed form of DNMT3B. In this study, we found that most of the lung cancer cell lines tested predominantly expressed DNMT3B isoforms without exons 21, 22 or both 21 and 22 (a region corresponding to the enzymatic domain of DNMT3B termed DNMT3B/∆DNMT3B-del. In normal bronchial epithelial cells, DNMT3B/ΔDNMT3B and DNMT3B/∆DNMT3B-del displayed equal levels of expression. In contrast, in patients with non-small cell lung cancer NSCLC, 111 (93% of the 119 tumors predominantly expressed DNMT3B/ΔDNMT3B-del, including 47 (39% tumors with no detectable DNMT3B/∆DNMT3B. Using a transgenic mouse model, we further demonstrated the biological impact of ∆DNMT3B4-del, the ∆DNMT3B-del isoform most abundantly expressed in NSCLC, in global DNA methylation patterns and lung tumorigenesis. Expression of ∆DNMT3B4-del in the mouse lungs resulted in an increased global DNA hypomethylation, focal DNA hypermethylation, epithelial hyperplastia and tumor formation when challenged with a tobacco carcinogen. Our results demonstrate ∆DNMT3B4-del as a critical factor in developing aberrant DNA methylation patterns during lung tumorigenesis and suggest that ∆DNMT3B4-del may be a target for lung cancer prevention.

  1. Rhodococcus opacus B4: a promising bacterium for production of biofuels and biobased chemicals.

    Science.gov (United States)

    Castro, Ana Rita; Rocha, Isabel; Alves, Maria Madalena; Pereira, Maria Alcina

    2016-12-01

    Bacterial lipids have relevant applications in the production of renewable fuels and biobased oleochemicals. The genus Rhodococcus is one of the most relevant lipid producers due to its capability to accumulate those compounds, mainly triacylglycerols (TAG), when cultivated on different defined substrates, namely sugars, organic acids and hydrocarbons but also on complex carbon sources present in industrial wastes. In this work, the production of storage lipids by Rhodococcus opacus B4 using glucose, acetate and hexadecane is reported for the first time and its productivity compared with Rhodococcus opacus PD630, the best TAG producer bacterium reported. Both strains accumulated mainly TAG from all carbon sources, being influenced by the carbon source itself and by the duration of the accumulation period. R. opacus B4 produced 0.09 and 0.14 g L(-1) at 24 and 72 h, with hexadecane as carbon source, which was 2 and 3.3 fold higher than the volumetric production obtained by R. opacus PD630. Both strains presented similar fatty acids (FA) profiles in intact cells while in TAG produced fraction, R. opacus B4 revealed a higher variability in fatty acid composition than R. opacus PD630, when both strains were cultivated on hexadecane. The obtained results open new perspectives for the use of R. opacus B4 to produce TAG, in particular using oily (alkane-contaminated) waste and wastewater as cheap raw-materials. Combining TAG production with hydrocarbons degradation is a promising strategy to achieve environmental remediation while producing added value compounds. PMID:27179529

  2. Leukotriene B4 enhances innate immune defense against the puerperal sepsis agent Streptococcus pyogenes

    OpenAIRE

    Soares, Elyara M.; Mason, Katie L.; Rogers, Lisa M.; Serezani, Carlos H.; Faccioli, Lucia H.; David M. Aronoff

    2013-01-01

    Puerperal sepsis is a leading cause of maternal mortality worldwide. Streptococcus pyogenes (Group A Streptococcus; GAS) is a major etiologic agent of severe postpartum sepsis yet little is known regarding the pathogenesis of these infections. Tissue macrophages provide innate defense against GAS and their actions are highly regulated. The intracellular second messenger cAMP can negatively regulate macrophage actions against GAS. Because leukotriene (LT) B4 has been shown to suppress intracel...

  3. Phase Constitution in Mixed Gd2O3 and B4C by Sintering at High Temperature

    Institute of Scientific and Technical Information of China (English)

    Wu Wenyuan; Xu Jingyu; Bian Xue; Hu Guangyong; Sun Shuchen; Tu Ganfeng

    2005-01-01

    The phase constitution in mixed Gd2O3 and B4C by sintering in graphite tube furnace at the temperature of 100~1489 ℃ in argon atmosphere was studied by means of XRD and TG-DTA. The results show that the impurity C reacts with O in the B4C at the temperature of 367~458 ℃. When the temperature is 800 ℃, Gd2O3 reacts with B4C, and the reaction products include GdB6, GdB4, GdBO3, GdBC and B. GdBC changes into GdB4 at 1200 ℃. When the temperature is 1470 ℃, GdB6 is obtained by the reaction of GdB4 with elemental B. The content of GdB6 is increasing with the prolonging time.

  4. Quantum criticality and inhomogeneous magnetic order in Fe-doped α -YbAlB4

    Science.gov (United States)

    MacLaughlin, D. E.; Kuga, K.; Shu, Lei; Bernal, O. O.; Ho, P.-C.; Nakatsuji, S.; Huang, K.; Ding, Z. F.; Tan, C.; Zhang, Jian

    2016-06-01

    The intermediate-valent polymorphs α - and β -YbAlB4 exhibit quantum criticality and other novel properties not usually associated with intermediate valence. Iron doping induces quantum criticality in α -YbAlB4 and magnetic order in both compounds. We report results of muon spin relaxation (μ SR ) experiments in α -YbAl1 -xFexB4 , x =0.014 and 0.25. For x =0.014 we find no evidence for magnetic order down to 25 mK. The dynamic muon spin relaxation rate λd exhibits a power-law temperature dependence λd∝T-a , a =0.40 (4 ) , in the temperature range 100 mK-2 K, in disagreement with predictions by theories of antiferromagnetic (AFM) or valence quantum critical behavior. For x =0.25 , where AFM order develops in the temperature range 7.5-10 K, we find coexistence of meso- or macroscopically segregated paramagnetic and AFM phases, with considerable disorder in the latter down to 2 K.

  5. Laser controlled melting of HSLA steel surface with presence of B4C particles

    Science.gov (United States)

    Yilbas, B. S.; Patel, F.; Karatas, C.

    2013-10-01

    Laser gas assisted melting of high strength low alloy steel surface is carried out. The alloy surface is pre-prepared to contain 5% B4C particles in a 40 μm thick carbon film prior to laser treatment process. Metallurgical and morphological changes in the laser treated layer are examined by using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. The residual stress developed and the microhardness of the resulting surface is measured. It is found that B4C particles remain in solid phase in the surface region due to their high melting temperature. The dense layer consisting of fine grains are formed at the surface and the feathery like structure is observed below the surface vicinity, which consists of martensite and nitride precipitations. The use of nitrogen at high pressure causes the formation of nitride compounds at the surface, which contributes to the volume shrinkage in the dense layer. Surface microhardness increases considerably because of attainment of high cooling rates, formation of nitride compounds, and presence of B4C particles at the surface.

  6. Further defining the phenotypic spectrum of B4GALT7 mutations.

    Science.gov (United States)

    Salter, Claire G; Davies, Justin H; Moon, Rebecca J; Fairhurst, Joanna; Bunyan, David; Foulds, Nicola

    2016-06-01

    Proteoglycans are components of the extracellular matrix with diverse biological functions. Defects in proteoglycan synthesis have been linked to several human diseases with common features of short stature, hypermobility, joint dislocations, and skeletal dysplasia. B4GALT7 encodes galactosyltransferase-I that catalyzes the addition of a galactose moiety to a xylosyl group in the tetrasaccharide linker of proteoglycans. Mutations in this gene have been associated with the rare progeroid form of Ehlers Danlos syndrome and in addition more recently found to underlie Larsen of Reunion Island syndrome. Nine individuals have been reported with a diagnosis of the progeroid form of Ehlers Danlos syndrome, four of whom have had molecular characterization showing homozygous or compound heterozygous mutations in B4GALT7. We report two newly described patients with compound heterozygous mutations in B4GALT7, and show that the six individuals with confirmed mutations do not have the progeroid features described in the original five patients with a clinical diagnosis of the progeroid form of Ehlers Danlos syndrome. We suggest that galactosyltransferase-I deficiency does not cause the progeroid form of Ehlers Danlos syndrome, but instead results in a clinically recognizable syndrome comprising short stature, joint hypermobility, radioulnar synostosis, and severe hypermetropia. This group of syndromic patients are on a phenotypic spectrum with individuals who have Larsen of Reunion Island syndrome, although the key features of osteopenia, fractures and hypermetropia have not been reported in patients from Reunion Island. © 2016 Wiley Periodicals, Inc. PMID:26940150

  7. Preparation and investigation of Al–4 wt% B4C nanocomposite powders using mechanical milling

    Indian Academy of Sciences (India)

    A Alizadeh; E Taheri-Nassaj; H R Baharvandi

    2011-08-01

    Boron carbide nanoparticles were produced using commercially available boron carbide powder (0.8 m).Mechanical milling was used to synthesize Al nanostructured powder in a planetary ball-mill under argon atmosphere up to 20 h. The same process was applied for Al–4 wt% B4C nanocomposite powders to explore the role of nanosize reinforcements on mechanical milling stages. Scanning electron microscopy (SEM) analysis as well as apparent density measurements were used to optimize the milling time needed for completion of the mechanical milling process. The results show that the addition of boron carbide particles accelerate the milling process, leading to a faster work hardening rate and fracture of aluminum matrix. FE-SEM images show that distribution of boron carbide particles in aluminum matrix reaches a full homogeneity when steady state takes place. The better distribution of reinforcement throughout the matrix would increase hardness of the powder. To study the compressibility of milled powder, modified heckel equation was used to consider the pressure effect on yield strength as well as reinforcing role of B4C particles. For better distribution of reinforcement throughout the matrix, , modified heckel equation was used to consider the pressure effect on yield strength as well as reinforcing role of B4C particles.

  8. Evolution of reinforcement distribution in Al-B4C composites during accumulative roll bonding

    International Nuclear Information System (INIS)

    Highlights: → ARB developed a nanostructure in the matrix of the Al-B4C composite. → An improvement in the reinforcement distribution was found by increasing ARB passes. → By progression of ARB from one to seven passes, hardness increased from 60 to 82 HV. -- Abstract: The distribution of reinforcement particles in the matrix of a composite is one of the most important microstructural features affecting properties. In this study, nanostructured Al-B4C composite sheets were processed by accumulative roll bonding (ARB), and the effect of the number of ARB cycles on the distribution of the B4C particles in the Al matrix was evaluated. From optical microscopic studies accompanied by the radial distribution function analysis, it was realized that the microstructure uniformity is improved by increasing the number of ARB cycles. It was in good agreement with bulk hardness measurements in which the standard deviation of the hardness values was decreased by progression of the ARB process. In addition, the X-ray diffraction peak profile analysis revealed that the area weighted mean crystallite size of the Al matrix decreases to the nanometric scale (114 nm) after seven ARB cycles.

  9. High temperature hall effect measurement system design, measurement and analysis

    Science.gov (United States)

    Berkun, Isil

    A reliable knowledge of the transport properties of semiconductor materials is essential for the development and understanding of a number of electronic devices. In this thesis, the work on developing a Hall Effect measurement system with software based data acqui- sition and control for a temperature range of 300K-700K will be described. A system was developed for high temperature measurements of materials including single crystal diamond, poly-crystalline diamond, and thermoelectric compounds. An added capability for monitor- ing the current versus voltage behavior of the contacts was used for studying the influence of ohmic and non-ohmic contacts on Hall Effect measurements. The system has been primar- ily used for testing the transport properties of boron-doped single crystal diamond (SCD) deposited in a microwave plasma-assisted chemical vapor deposition (MPCVD) reactor [1]. Diamond has several outstanding properties that are of high interest for its development as an electronic material. These include a relatively wide band gap of 5.5 (eV), high thermal conductivity, high mobility, high saturation velocity, and a high breakdown voltage. For a temperature range of 300K-700K, IV curves, Hall mobilities and carrier concentrations are shown. Temperature dependent Hall effect measurements have shown carrier concentrations from below 1017cm --3 to approximately 1021 cm--3 with mobilities ranging from 763( cm2/V s) to 0.15(cm 2/V s) respectively. Simulation results have shown the effects of single and mixed carrier models, activation energies, effective mass and doping concentrations. These studies have been helpful in the development of single crystal diamond for diode applications. Reference materials of Ge and GaAs were used to test the Hall Effect system. The system was also used to characterize polycrystalline diamond deposited on glass for electrochemical applications, and Mg2(Si,Sn) compounds which are promising candidates of low-cost, light weight and non

  10. Research reactors

    International Nuclear Information System (INIS)

    This article proposes an overview of research reactors, i.e. nuclear reactors of less than 100 MW. Generally, these reactors are used as neutron generators for basic research in matter sciences and for technological research as a support to power reactors. The author proposes an overview of the general design of research reactors in terms of core size, of number of fissions, of neutron flow, of neutron space distribution. He outlines that this design is a compromise between a compact enough core, a sufficient experiment volume, and high enough power densities without affecting neutron performance or its experimental use. The author evokes the safety framework (same regulations as for power reactors, more constraining measures after Fukushima, international bodies). He presents the main characteristics and operation of the two families which represent almost all research reactors; firstly, heavy water reactors (photos, drawings and figures illustrate different examples); and secondly light water moderated and cooled reactors with a distinction between open core pool reactors like Melusine and Triton, pool reactors with containment, experimental fast breeder reactors (Rapsodie, the Russian BOR 60, the Chinese CEFR). The author describes the main uses of research reactors: basic research, applied and technological research, safety tests, production of radio-isotopes for medicine and industry, analysis of elements present under the form of traces at very low concentrations, non destructive testing, doping of silicon mono-crystalline ingots. The author then discusses the relationship between research reactors and non proliferation, and finally evokes perspectives (decrease of the number of research reactors in the world, the Jules Horowitz project)

  11. Reactor physics and reactor computations

    International Nuclear Information System (INIS)

    Mathematical methods and computer calculations for nuclear and thermonuclear reactor kinetics, reactor physics, neutron transport theory, core lattice parameters, waste treatment by transmutation, breeding, nuclear and thermonuclear fuels are the main interests of the conference

  12. Evolving role of 2B4/CD244 in T and NK cell responses during virus infection

    Directory of Open Access Journals (Sweden)

    Stephen Noel Waggoner

    2012-12-01

    Full Text Available The signaling lymphocyte activation molecule (SLAM family receptor, 2B4/CD244, was first implicated in anti-viral immunity by the discovery that mutations of the SLAM-associated protein, SAP/SH2D1A, impaired 2B4-dependent stimulation of T and natural killer (NK cell anti-viral functions in X-linked lymphoproliferative (XLP syndrome patients with uncontrolled Epstein-Barr virus (EBV infections. Engagement of 2B4 has been variably shown to either activate or inhibit lymphocytes which express this receptor. While SAP expression is required for stimulatory functions of 2B4 on lymphocytes, it remains unclear whether inhibitory signals derived from 2B4 can predominate even in the presence of SAP. Regardless, mounting evidence suggests that 2B4 expression by NK and CD8 T cells is altered by virus infection in mice as well as in humans, and 2B4-mediated signaling may be an important determinant of effective immune control of chronic virus infections. In this review, recent findings regarding the expression and function of 2B4 as well as SAP on T and NK cells during virus infection is discussed, with a focus on the role of 2B4-CD48 interactions in crosstalk between innate and adaptive immunity.

  13. Preparation and characterization of B4C coatings for advanced research light sources.

    Science.gov (United States)

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30-60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is considerably

  14. Preparation and characterization of B4C coatings for advanced research light sources

    Science.gov (United States)

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30–60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is

  15. 75 FR 22770 - Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment

    Science.gov (United States)

    2010-04-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment April 22, 2010. In accordance with the National Environmental Policy Act of 1969, as amended,...

  16. Charge carrier coherence and Hall effect in organic semiconductors

    Science.gov (United States)

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-03-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

  17. ErbB4 localization to cardiac myocyte nuclei, and its role in myocyte DNA damage response

    Energy Technology Data Exchange (ETDEWEB)

    Icli, Basak [Department of Medicine, Cardiovascular Division, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Bharti, Ajit [Center of Molecular Stress Response Whitaker Cardiovascular Institute, Department of Medicine, Boston University Medical Center, Boston, MA 02118 (United States); Pentassuglia, Laura; Peng, Xuyang [Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (United States); Sawyer, Douglas B., E-mail: douglas.b.sawyer@vanderbilt.edu [Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (United States)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer ErbB4 localizes to cardiac myocyte nuclei as a full-length receptor. Black-Right-Pointing-Pointer Cardiac myocytes express predominantly JM-a/CYT-1 ErbB4. Black-Right-Pointing-Pointer Myocyte p53 activation in response to doxorubicin requires ErbB4 activity. -- Abstract: The intracellular domain of ErbB4 receptor tyrosine kinase is known to translocate to the nucleus of cells where it can regulate p53 transcriptional activity. The purpose of this study was to examine whether ErbB4 can localize to the nucleus of adult rat ventricular myocytes (ARVM), and regulate p53 in these cells. We demonstrate that ErbB4 does locate to the nucleus of cardiac myocytes as a full-length protein, although nuclear location occurs as a full-length protein that does not require Protein Kinase C or {gamma}-secretase activity. Consistent with this we found that only the non-cleavable JM-b isoform of ErbB4 is expressed in ARVM. Doxorubicin was used to examine ErbB4 role in regulation of a DNA damage response in ARVM. Doxorubicin induced p53 and p21 was suppressed by treatment with AG1478, an EGFR and ErbB4 kinase inhibitor, or suppression of ErbB4 expression with small interfering RNA. Thus ErbB4 localizes to the nucleus as a full-length protein, and plays a role in the DNA damage response induced by doxorubicin in cardiac myocytes.

  18. Neutral-current Hall effects in disordered graphene

    OpenAIRE

    Wang, Yilin; Cai, Xinghan; Reutt-Robey, Janice; Fuhrer, Michael S.

    2015-01-01

    A non-local Hall bar geometry is used to detect neutral-current Hall effects in graphene on silicon dioxide. Disorder is tuned by the addition of Au or Ir adatoms in ultra-high vacuum. A reproducible neutral-current Hall effect is found in both as-fabricated and adatom-decorated graphene. The Hall angle exhibits a complex but reproducible dependence on gate voltage and disorder, and notably breaks electron-hole symmetry. An exponential dependence on length between Hall and inverse-Hall probes...

  19. Chemical compatibility of B-4C/Na/S.S. system. Pt.2: Effects of test period and oxygen content in sodium

    International Nuclear Information System (INIS)

    The simulation specimens of the fast breeder reactor' control rod were put into the thermal convection sodium loop, and the out of pile tests for B4C/Na/S.S. system chemical compatibility were performed at 550 degree C, and the effects of the test period and oxygen content in sodium on the compatibility characters were investigated. The appearance of B4C pellets is integral, and crack or break are not found after compatible test. There is B penetration in cladding inner surface, the amount of B penetration is proportional to the square root of the test period. The depth of B penetration is not changed with the add of the test period. The microhardness at the cladding inner surface increases clearly, its increment is increasing slightly with the add of the test period. The depth of the hardening layers is about 40 μm for different test periods. The reaction products Cr2B, Na4B10O17, B6Fe23, CrB, Nib and NiB12 are formed according to priority at the cladding inner surface for 80 to 400 d. The diffusion of B into the cladding relates to the temperature, test period and the oxygen content, and the oxygen promotes the B diffusion

  20. Extrinsic spin Hall effect in graphene

    Science.gov (United States)

    Rappoport, Tatiana

    The intrinsic spin-orbit coupling in graphene is extremely weak, making it a promising spin conductor for spintronic devices. In addition, many applications also require the generation of spin currents in graphene. Theoretical predictions and recent experimental results suggest one can engineer the spin Hall effect in graphene by greatly enhancing the spin-orbit coupling in the vicinity of an impurity. The extrinsic spin Hall effect then results from the spin-dependent skew scattering of electrons by impurities in the presence of spin-orbit interaction. This effect can be used to efficiently convert charge currents into spin-polarized currents. I will discuss recent experimental results on spin Hall effect in graphene decorated with adatoms and metallic cluster and show that a large spin Hall effect can appear due to skew scattering. While this spin-orbit coupling is small if compared with what it is found in metals, the effect is strongly enhanced in the presence of resonant scattering, giving rise to robust spin Hall angles. I will present our single impurity scattering calculations done with exact partial-wave expansions and complement the analysis with numerical results from a novel real-space implementation of the Kubo formalism for tight-binding Hamiltonians. The author acknowledges the Brazilian agencies CNPq, CAPES, FAPERJ and INCT de Nanoestruturas de Carbono for financial support.

  1. The Hall effect in star formation

    CERN Document Server

    Braiding, Catherine R

    2011-01-01

    Magnetic fields play an important role in star formation by regulating the removal of angular momentum from collapsing molecular cloud cores. Hall diffusion is known to be important to the magnetic field behaviour at many of the intermediate densities and field strengths encountered during the gravitational collapse of molecular cloud cores into protostars, and yet its role in the star formation process is not well-studied. We present a semianalytic self-similar model of the collapse of rotating isothermal molecular cloud cores with both Hall and ambipolar diffusion, and similarity solutions that demonstrate the profound influence of the Hall effect on the dynamics of collapse. The solutions show that the size and sign of the Hall parameter can change the size of the protostellar disc by up to an order of magnitude and the protostellar accretion rate by fifty per cent when the ratio of the Hall to ambipolar diffusivities is varied between -0.5 <= eta_H / eta_A <= 0.2. These changes depend upon the orien...

  2. Anisotropic magnetic and superconducting properties of single crystals of RERh4B4 compounds

    International Nuclear Information System (INIS)

    We report the synthesis of small single crystals of several RERh4B4 compounds where RE = Sm, Gd, Tb, Dy, Ho, Er, and Tm using a flux-growth technique. Measurements of the ac electrical resistance R in zero and applied magnetic fields and dc magnetic susceptibility are reported. The upper critical magnetic field H/sub c/2(T) determined from the resistance measurements for RE = Sm, Er, and Tm are also presented. Considerable anisotropy of H/sub c/2(T) is observed for Er and Tm, while very little is found for Sm

  3. Coxeter groups $A_{4}$, $B_{4}$ and $D_{4}$ for two-qubit systems

    Indian Academy of Sciences (India)

    Ramazan Koç; M Yakup Haciibrahimoğlu; Mehmet Koca

    2013-08-01

    The Coxeter–Weyl groups $W(A_{4})$, $W(B_{4})$ and $W(D_{4})$ have proven very useful for two-qubit systems in quantum information theory. A simple technique is employed to construct the unitary matrix representations of the groups, based on quaternionic transformation of the usual reflection matrices. The von Neumann entropy of each reduced density matrix is calculated. It is shown that these unitary matrix representations are naturally related to various universal quantum gates and they lead to entangled states. Canonical decomposition of generators in terms of fundamental gate representations is given to construct the quantum circuits.

  4. Expression of erB4/HER4 in Gastric Carcinoma

    Institute of Scientific and Technical Information of China (English)

    YU Yi-ming; LIU Zhong; DENG Zai-chun; TAN Yun-shan; XU Yong-hua

    2008-01-01

    Objective:To explore the expression of HER4 in gastric carcinoma and elucidate the relationship between its overexpression and clinical pathology. Methods:A total of 68 samples of gastric carcinoma were examined for the expression of HER4 by immunohistochemical assay. Results:HER4 was overexpressed in 79.41% of gastric carcinoma.The overexpression of HER4 correlated only with lymph node metastasis and TNM staging. Conclusion:erbB4 is one of the genes to regulate the growth of gastric carcinoma and artificial interference the overexpression of HER4 may be an effective treatment of gastric carcinoma.

  5. Changing photospheric vector magnetic fields associated with a B4.2-class solar flare

    Science.gov (United States)

    Su, Jiangtao; Liu, Yu; Shen, Yuandeng

    2013-07-01

    Recent observations have provided evidence that the solar photospheric magnetic fields could have rapid and permanent changes in both longitudinal and transverse components associated with large (X- or M-class) solar flares. However, few observations have been reported about small flares. In this paper we find the observational evidence of changing photospheric vector magnetic fields associated with a B4.2-class flare obtained with the Solar Magnetic Field Telescope (SMFT) installed at Huairou Solar Observing Station (HSOS) of Nation Astronomical Observatories of Chinese Academy of Sciences.

  6. Piezo Voltage Controlled Planar Hall Effect Devices.

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-01-01

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials. PMID:27329068

  7. Mesoscopic effects in the quantum Hall regime

    Indian Academy of Sciences (India)

    R N Bhatt; Xin Wan

    2002-02-01

    We report results of a study of (integer) quantum Hall transitions in a single or multiple Landau levels for non-interacting electrons in disordered two-dimensional systems, obtained by projecting a tight-binding Hamiltonian to the corresponding magnetic subbands. In finite-size systems, we find that mesoscopic effects often dominate, leading to apparent non-universal scaling behavior in higher Landau levels. This is because localization length, which grows exponentially with Landau level index, exceeds the system sizes amenable to the numerical study at present. When band mixing between multiple Landau levels is present, mesoscopic effects cause a crossover from a sequence of quantum Hall transitions for weak disorder to classical behavior for strong disorder. This behavior may be of relevance to experimentally observed transitions between quantum Hall states and the insulating phase at low magnetic fields.

  8. Extrinsic Spin Hall Effect from First Principles

    Science.gov (United States)

    Gradhand, Martin; Fedorov, Dmitry V.; Zahn, Peter; Mertig, Ingrid

    2010-05-01

    We present an ab initio description of the spin Hall effect in metals. Our approach is based on density functional theory in the framework of a fully relativistic Korringa-Kohn-Rostoker method and the solution of a linearized Boltzmann equation including the scattering-in term (vertex corrections). The skew scattering mechanism at substitutional impurities is considered. Spin-orbit coupling in the host as well as at the impurity atom and the influence of spin-flip processes are fully taken into account. A sign change of the spin Hall effect in Cu and Au hosts is obtained as a function of the impurity atom, and even light elements like Li can cause a strong effect. It is shown that the gigantic spin Hall effect in Au can be caused by skew scattering at C and N impurities which are typical contaminations in a vacuum chamber.

  9. Spin Hall Effect in Doped Semiconductor Structures

    Science.gov (United States)

    Tse, Wang-Kong; Das Sarma, Sankar

    2006-03-01

    We present a microscopic theory of the extrinsic spin Hall effect based on the diagrammatic perturbation theory. Side-jump (SJ) and skew-scattering (SS) contributions are explicitly taken into account to calculate the spin Hall conductivity, and we show their effects scale as σxy^SJ/σxy^SS ˜(/τ)/ɛF, where τ being the transport relaxation time. Motivated by recent experimental work we apply our theory to n-doped and p-doped 3D and 2D GaAs structures, obtaining analytical formulas for the SJ and SS contributions. Moreover, the ratio of the spin Hall conductivity to longitudinal conductivity is found as σs/σc˜10-3-10-4, in reasonable agreement with the recent experimental results of Kato et al. [Science 306, 1910 (2004)] in n-doped 3D GaAs system.

  10. Graphene-based Hall Sensors for direct magnetic imaging by using Scanning Hall Probe Microscope

    Science.gov (United States)

    Sonusen, Selda; Aksoy, Seda; Dede, Munir; Oral, Ahmet

    2013-03-01

    Graphene has been attracting great interest due to its unique electronic and mechanical properties for both fundamental and experimental studies since 2004. Graphene is a promising material for many applications in high speed electronic and spintronic devices as well as sensors. Its high mobility makes graphene a good candidate for magnetic imaging in Scanning Hall Probe Microscope (SHPM). Hall probes are used to scan the magnetic samples to image magnetic domains in SHPM. In this work, single layer graphene produced by chemical vapor deposition technique is used to fabricate Hall sensors by optical and the e-beam lithography with sizes from 500 nm to a few micrometers. The Hall crosses are characterized by Raman mapping to make sure that they are made of a single layer graphene. The Graphene Hall Sensors noise spectra is measured as a function of different bias currents and carrier concentrations at 300 K, 77 K and 4.24K. The imaging performance of the Hall sensor will be demonstrated at different temperatures by imaging a garnet crystal using a Low Temperature Scanning Hall Probe Microscope (LT-SHPM).

  11. Roger Calder (1934 – 2014)

    CERN Multimedia

    2014-01-01

    Roger joined CERN’s Accelerator-Research Division in May 1963, at the beginning of the Intersecting Storage Rings (ISR) project. The challenge was to evacuate the two beam pipes of about 1 km each to 10-7 Pa and to obtain a beam lifetime of 20 hours. An ultra-high vacuum system of this size and complexity required the most advanced technologies available.   Among the outstanding contributions by Roger were: the choice of turbomolecular- and ion-pumps, low outgassing rates and an all-metal system bakeable to 300°C. Still today, Roger’s name is linked to "900°C vacuum degassed stainless steel" for very low hydrogen outgassing. The unexpected dynamic pressure run-away during the ISR start-up, at only a few A of beam, was quickly identified as the "ion-induced pressure bump instability". Among Roger’s efforts to mitigate this effect, the pumping system was supplemented with titanium sublimation pumps. In a second s...

  12. Reactor building

    International Nuclear Information System (INIS)

    The whole reactor building is accommodated in a shaft and is sealed level with the earth's surface by a building ceiling, which provides protection against penetration due to external effects. The building ceiling is supported on walls of the reactor building, which line the shaft and transfer the vertical components of forces to the foundations. The thickness of the walls is designed to withstand horizontal pressure waves in the floor. The building ceiling has an opening above the reactor, which must be closed by cover plates. Operating equipment for the reactor can be situated above the building ceiling. (orig./HP)

  13. Nuclear fission: the interplay of science and technology.

    Science.gov (United States)

    Stoneham, A M

    2010-07-28

    When the UK's Calder Hall nuclear power station was connected to the grid in 1956, the programmes that made this possible involved a powerful combination of basic and applied research. Both the science and the engineering were novel, addressing new and challenging problems. That the last Calder Hall reactor was shut down only in 2003 attests to the success of the work. The strengths of bringing basic science to bear on applications continued to be recognized until the 1980s, when government and management fashions changed. This paper identifies a few of the technology challenges, and shows how novel basic science emerged from them and proved essential in their resolution. Today, as the threat of climate change becomes accepted, it has become clear that there is no credible solution without nuclear energy. The design and construction of new fission reactors will need continuing innovation, with the interplay between the science and technology being a crucial component.

  14. Consolidation of B4C-TaB2 eutectic composites by spark plasma sintering

    Directory of Open Access Journals (Sweden)

    Dmytro Demirskyi

    2015-12-01

    Full Text Available The in situ synthesis/consolidation of B4C-TaB2 eutectic composites by spark plasma sintering (SPS is reported. The microstructure–property relations were determined for composites with the B4C-TaB2 eutectic composition as functions of TaB2 content, and TaB2-TaB2 interlamellar spacing. A clear maximum in fracture toughness was identified (∼4.5 MPa m1/2 for eutectic composites with interlamellar spacing between 0.9 and 1.1 μm. The composites with the hypereutectic composition of 40 mol.% TaB2 obtained by SPS exhibited lower Vickers hardness (25–26 GPa but higher indentation fracture toughness (up to 4.9 MPa m1/2 than eutectic composites with 30–35 mol.% of TaB2.

  15. Electrical properties of AC3B4O12-type perovskite ceramics with different cation vacancies

    International Nuclear Information System (INIS)

    Highlights: • AC3B4O12 perovskite with different concentration cation vacancies were prepared. • Cell parameter decreases with the increase of concentration of cation vacancies. • PTCO and CTO remain high dielectric permittivity but depress loss greatly. • Dielectric loss associates with cation vacancies and motion of oxygen vacancies. - Abstract: AC3B4O12-type perovskite CaCu3Ti4O12 (CCTO), □0.34Pr0.67Cu3Ti4O12 (PCTO), □1Cu3Ta2Ti2O12 (CTTO), □2Cu2Ta4O12 (CTO) ceramics with different concentration cation vacancies were prepared through traditional solid state reaction method. X-ray diffraction analysis indicated that CCTO and PCTO are perovskite cubic with space group Im-3 (no. 204) while CTTO and CTO are Pm-3 (no. 200). Cell parameter of the samples dramatically increases with the increase of cation vacancies. Dielectric permittivity of them maintains very high value of ∼104 from room temperature to 550 K but the dielectric loss is depressed with the increase of cation vacancies in the same space group. The dielectric properties and conductivity behavior were described by the Debye relaxation and the universal dielectric response, respectively. The effect mechanism of cation vacancy and crystal structure on carrier transposition were discussed

  16. Helium bubble evolution in ion irradiated Al/B4C metal matrix composite

    International Nuclear Information System (INIS)

    Graphical abstract: Scheme of combined irradiation includes a pre-implantation of 400 keV He+ to 1.0 × 1016 ions/cm2 followed by a 1.5 MeV proton irradiation to 2.2 × 1019 ions/cm2 on the perpendicular surface. TEM samples were prepared by FIB. The area suffered with both He+ pre-implantation and proton irradiation was marked as light blue. - Abstract: Helium behavior in Al/B4C metal matrix composite with two different sets of ion irradiation conditions has been investigated by transmission electron microscopy. Helium bubbles in Al were found to be much larger than those in B4C after a helium fluence of 1.5 × 1017 ions/cm2 at the room temperature. Also, bubbles at grain boundaries and their vicinity in aluminum are faceted. With additional proton irradiation, a bubble denuded zone along the aluminum grain boundary appears. The results are discussed in terms of the energetics of the material system

  17. HoB4 at high pressure and low temperature: an experimental and theoretical study

    DEFF Research Database (Denmark)

    Olsen, J. Staun; Waśkowska, A.; Gerward, Leif;

    2011-01-01

    Single crystals of HoB4 have been grown and used for synchrotron X-ray diffraction studies at pressures up to 23GPa and temperatures down to 100K. The experimental bulk modulus 195 ± 6GPa is in good agreement with 188.4 and 198.2GPa values calculated in the LSDA and LSDA+U approximations, indicat......Single crystals of HoB4 have been grown and used for synchrotron X-ray diffraction studies at pressures up to 23GPa and temperatures down to 100K. The experimental bulk modulus 195 ± 6GPa is in good agreement with 188.4 and 198.2GPa values calculated in the LSDA and LSDA+U approximations......, indicating that mainly the boron sublattice determines the bulk modulus. The experimental c/a ratio decreases slightly with pressure, but the effect is small. An orthorhombic distortion begins at Tc ≈ 295K, i.e. at a temperature much higher than the Neel temperature TN1=7.1K. The behavior is interpreted...

  18. Quantum Hall Effect and Chaotic Motion in Phase Space

    OpenAIRE

    Ghaboussi, F.

    1996-01-01

    We discuss the relation between the Quantum Hall behaviour of charged carriers and their chaotic motion in phase space. It is shown that the quantum Hall diagram is comparable with the stepped diagram in phase space of a chaotic motion.

  19. Origin of Spin Hall Effect (Reply to Comment)

    OpenAIRE

    Chudnovsky, E. M.

    2008-01-01

    Conceptual framework behind the intrinsic spin Hall effect in three-dimensional conductors is discussed. Theory suggests how the spin Hall current should depend on symmetry and orientation of the crystal.

  20. Improved Readout For Micromagnet/Hall-Effect Memories

    Science.gov (United States)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.

    1993-01-01

    Two improved readout circuits for micromagnet/Hall-effect random-access memories designed to eliminate current shunts introducing errors into outputs of older readout circuits. Incorporate additional switching transistors to isolate Hall sensors as needed.

  1. Inverse spin Hall effect by spin injection

    Science.gov (United States)

    Liu, S. Y.; Horing, Norman J. M.; Lei, X. L.

    2007-09-01

    Motivated by a recent experiment [S. O. Valenzuela and M. Tinkham, Nature (London) 442, 176 (2006)], the authors present a quantitative microscopic theory to investigate the inverse spin-Hall effect with spin injection into aluminum considering both intrinsic and extrinsic spin-orbit couplings using the orthogonalized-plane-wave method. Their theoretical results are in good agreement with the experimental data. It is also clear that the magnitude of the anomalous Hall resistivity is mainly due to contributions from extrinsic skew scattering.

  2. Prototype dining hall energy efficiency study

    Energy Technology Data Exchange (ETDEWEB)

    Mazzucchi, R.P.; Bailey, S.A.; Zimmerman, P.W.

    1988-06-01

    The energy consumption of food service facilities is among the highest of any commercial building type, owing to the special requirements for food preparation, sanitation, and ventilation. Consequently, the US Air Force Engineering and Services Center (AFESC) contracted with Pacific Northwest Laboratory (PNL) to collect and analyze end-use energy consumption data for a prototypical dining hall and make specific recommendations on cost-effective energy conservation options. This information will be used to establish or update criteria for dining hall designs and retrofits as appropriate. 6 refs., 21 figs., 23 tabs.

  3. EL CROWN HALL. CONTEXTO Y PROYECTO

    Directory of Open Access Journals (Sweden)

    Laura Lizondo Sevilla

    2010-05-01

    Full Text Available RESUMEN El artículo enmarca el edificio del Crown Hall en el contexto docente y arquitectónico de Mies van der Rohe. Revisa sus inicios en la Bauhaus con su primera intervención en un espacio docente para la Bauhaus de Berlín en 1932, así como su marcha a Estados Unidos, los planteamientos arquitectónicos del campus del IIT y el proyecto del Crown Hall. El texto incide en el estudio del proceso proyectual del Crown Hall analizando la evolución de su concepción arquitectónica a través de las diferentes versiones del proyecto. Se constata la transición desde los primeros planteamientos arquitectónicos de los edificios del campus del IIT proyectados por Mies hacia el planteamiento del gran espacio unitario del Crown Hall. Este proyecto se puede entender desde la creciente importancia de la estructura, la claridad constructiva y el manejo del acero y vidrio como únicos materiales de la imagen del edificio y el carácter flexible y unitario del espacio. Finalmente se hace referencia al concepto del "espacio universal" en la arquitectura de Mies, como un concepto abstracto que supera los de flexibilidad de uso o unidad espacial, insinuando, a modo de reflexión, las principales variables que definirían el espacio universal miesiano.SUMMARY The article showcases the Crown Hall building in the educational and architectural context of Mies van der Rohe. It reviews his beginnings in the Bauhaus with his first intervention in an educational space for the Bauhaus of Berlin in 1932, as well as his sojourn to the United States, and the architectural approaches to the IIT campus and the Crown Hall project. The text touches on the study of the planning process for the Crown Hall, analysing the evolution of its architectural conception, through the different versions of the project. The article covers the transition from the first architectural approaches for the IIT campus buildings, planned by Mies, to the approach of the large unitary space of

  4. Acoustics in rock and pop music halls

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    The existing body of literature regarding the acoustic design of concert halls has focused almost exclusively on classical music, although there are many more performances of rhythmic music, including rock and pop. Objective measurements were made of the acoustics of twenty rock music venues in...... Denmark and a questionnaire was used in a subjective assessment of those venues with professional rock musicians and sound engineers. Correlations between the objective and subjective results lead, among others, to a recommendation for reverberation time as a function of hall volume. Since the bass...

  5. Acoustics in rock and pop music halls

    DEFF Research Database (Denmark)

    Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    The existing body of literature regarding the acoustic design of concert halls has focused almost exclusively on classical music, although there are many more performances of rhythmic music, including rock and pop. Objective measurements were made of the acoustics of twenty rock music venues...... in Denmark and a questionnaire was used in a subjective assessment of those venues with professional rock musicians and sound engineers. Correlations between the objective and subjective results lead, among others, to a recommendation for reverberation time as a function of hall volume. Since the bass...

  6. El Sueño como personaje alegórico en dos autos de Calderón: La siembra del Señor (antes de 1655) y Sueños hay que verdad son (1670)

    OpenAIRE

    Gilbert, Françoise

    2008-01-01

    International audience Este artículo analiza la ambigüedad del personaje alegórico de Sueño en dos autos sacramentales de Calderón, La siembra del señor y Sueños hay que verdad son. En el primero, la figura de Sueño, connotada como 'acto de dormir', se alia con la Culpa para contrarrestar la instauración de la Edad de Gracia. Pero con la muerte de Emanuel y la llegada de la Ley Nueva, el personaje se vuelve la voz anunciadora del advenimiento de la Edad de Gracia. En Sueños hay que verdad ...

  7. Charge-Hall effect driven by spin force: reciprocal of the spin-Hall effect

    OpenAIRE

    zhang, ping; Niu, Qian

    2004-01-01

    A new kind of charge-Hall effect is shown. Unlike in the usual Hall effect, the driving force in the longitudinal direction is a spin force, which may originate from the gradient of a Zeeman field or a spin-dependent chemical potential. The transverse force is provided by a Berry curvature in a mixed position-momentum space. We can establish an Onsager relation between this effect and the spin-Hall effect provided the spin current in the latter is modified by a torque dipole contribution. Thi...

  8. Inverse Spin Hall Effect and Anomalous Hall Effect in a Two-Dimensional Electron Gas

    OpenAIRE

    Schwab, Peter; Raimondi, Roberto; Gorini, Cosimo

    2010-01-01

    We study the coupled dynamics of spin and charge currents in a two-dimensional electron gas in the transport diffusive regime. For systems with inversion symmetry there are established relations between the spin Hall effect, the anomalous Hall effect and the inverse spin Hall effect. However, in two-dimensional electron gases of semiconductors like GaAs, inversion symmetry is broken so that the standard arguments do not apply. We demonstrate that in the presence of a Rashba type of spin-orbit...

  9. Flux State in von Neumann lattice and Fractional Hall Effect

    OpenAIRE

    Ishikawa, Kenzo; Maeda, Nobuki

    1996-01-01

    Formulation of quantum Hall dynamics using von Neumann lattice of guiding center coordinates is presented. A topological invariant expression of the Hall conductance is given and a new mean field theory of the fractional Hall effect based on flux condensation is proposed. Because our mean field Hamiltonian has the same form as Hofstadter Hamiltonian, it is possible to understand characteristic features of the fractional Hall effect from Hofstadter's spectrum. Energy gap and other physical qua...

  10. Intrinsic Spin and Orbital-Angular-Momentum Hall Effect

    OpenAIRE

    S. Zhang; Yang, Z.

    2004-01-01

    A generalized definition of intrinsic and extrinsic transport coefficients is introduced. We show that transport coefficients from the intrinsic origin are solely determined by local electronic structure, and thus the intrinsic spin Hall effect is not a transport phenomenon. The intrinsic spin Hall current is always accompanied by an equal but opposite intrinsic orbital-angular-momentum Hall current. We prove that the intrinsic spin Hall effect does not induce a spin accumulation at the edge ...

  11. Localization corrections to the anomalous Hall effect in a ferromagnet

    OpenAIRE

    Dugaev, V. K.; Crepieux, A.; Bruno, P

    2001-01-01

    We calculate the localization corrections to the anomalous Hall conductivity related to the contribution of spin-orbit scattering into the current vertex (side-jump mechanism). We show that in contrast to the ordinary Hall effect, there exists a nonvanishing localization correction to the anomalous Hall resistivity. The correction to the anomalous Hall conductivity vanishes in the case of side-jump mechanism, but is nonzero for the skew scattering. The total correction to the nondiagonal cond...

  12. Theory of Phonon Hall Effect in Paramagnetic Dielectrics

    OpenAIRE

    Sheng, L.; Sheng, D. N.; Ting, C. S.

    2006-01-01

    Based upon spin-lattice interaction, we propose a theoretical model for the phonon Hall effect in paramagnetic dielectrics. The thermal Hall conductivity is calculated by using the Kubo formula. Our theory reproduces the essential experimental features of the phonon Hall effect discovered recently in ionic dielectric Tb$_3$Ga$_5$O$_{12}$, including the sign, magnitude and linear magnetic field dependence of the thermal Hall conductivity.

  13. The anomalous Hall conductivity due to the vector spin chirality

    OpenAIRE

    Taguchi, Katsuhisa; Tatara, Gen

    2008-01-01

    We study theoretically the anomalous Hall effect due to the vector spin chirality carried by the local spins in the $s$-$d$ model. We will show that the vector spin chirality indeed induces local Hall effect in the presence of the electron spin polarization, while the global Hall effect vanishes if electron transport is homogeneous. This anomalous Hall effect can be interpreted in terms of the rotational component of the spin current associated with the vector chirality.

  14. Anomalous Josephson Hall effect in magnet/triplet superconductor junctions

    OpenAIRE

    Yokoyama, Takehito

    2015-01-01

    We investigate anomalous Hall effect in a magnet coupled to a triplet superconductor under phase gradient. It is found that the anomalous Hall supercurrent arises from non-trivial structure of the magnetization. The magnetic structure manifested in the Hall supercurrent is characterized by even order terms of the exchange coupling, essentially different from that discussed in the context of anomalous Hall effect, reflecting the disspationless nature of supercurrent. We also discuss a possible...

  15. Hall Effect Sensors Design, Integration and Behavior Analysis

    Directory of Open Access Journals (Sweden)

    Maher Kayal

    2013-02-01

    Full Text Available The present paper focuses on various aspects regarding Hall Effect sensors’ design, integration, and behavior analysis. In order to assess their performance, different Hall Effect geometries were tested for Hall voltage, sensitivity, offset, and temperature drift. The residual offset was measured both with an automated measurement setup and by manual switching of the individual phases. To predict Hall sensors performance prior to integration, three-dimensional physical simulations were performed.

  16. Charge carrier coherence and Hall effect in organic semiconductors

    OpenAIRE

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-01-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experimen...

  17. New geometries for high spatial resolution hall probes

    OpenAIRE

    GUILLOU, H.; Kent, A. D.; Stupian, G. W.; Leung, M. S.

    2002-01-01

    The Hall response function of symmetric and asymmetric planar Hall effect devices is investigated by scanning a magnetized tip above a sensor surface while simultaneously recording the topography and the Hall voltage. Hall sensor geometries are tailored using a Focused Ion Beam, in standard symmetric and new asymmetric geometries. With this technique we are able to reduce a single voltage probe to a narrow constriction 20 times smaller than the other device dimensions. We show that the respon...

  18. Parallel Hall effect from 3D single-component metamaterials

    OpenAIRE

    Kern, Christian; Kadic, Muamer; Wegener, Martin

    2015-01-01

    We propose a class of three-dimensional metamaterial architectures composed of a single doped semiconductor (e.g., n-Si) in air or vacuum that lead to unusual effective behavior of the classical Hall effect. Using an anisotropic structure, we numerically demonstrate a Hall voltage that is parallel---rather than orthogonal---to the external static magnetic-field vector ("parallel Hall effect"). The sign of this parallel Hall voltage can be determined by a structure parameter. Together with the...

  19. Hall Effect Sensors Design, Integration and Behavior Analysis

    OpenAIRE

    Maher Kayal; Maria-Alexandra Paun; Jean-Michel Sallese

    2013-01-01

    The present paper focuses on various aspects regarding Hall Effect sensors’ design, integration, and behavior analysis. In order to assess their performance, different Hall Effect geometries were tested for Hall voltage, sensitivity, offset, and temperature drift. The residual offset was measured both with an automated measurement setup and by manual switching of the individual phases. To predict Hall sensors performance prior to integration, three-dimensional physical simulations were perfor...

  20. Orbital angular momentum driven intrinsic spin Hall effect

    OpenAIRE

    Jung, Wonsig; Go, Dongwook; Lee, Hyun-Woo; Kim, Changyoung

    2014-01-01

    We propose a mechanism of intrinsic spin Hall effect (SHE). In this mechanism, local orbital angular momentum (OAM) induces electron position shift and couples with the bias electric field to generate orbital Hall effect (OHE). SHE then emerges as a concomitant effect of OHE through the atomic spin-orbit coupling. Spin Hall conductivity due to this mechanism is estimated to be comparable to experimental values for heavy metals. This mechanism predicts the sign change of the spin Hall conducti...

  1. Nuclear Reactor RA Safety Report, Vol. 3, Building and installations

    International Nuclear Information System (INIS)

    RA reactor building is built of concrete and bricks as an enclosed building with limited number of controlled openings, and limited number of doors and windows. It is made of three parts: central; circular annex in the central part; sanitary corridor. The largest part of the RA reactor building is the reactor hall. This volume includes detailed description, figure and diagrams showing building characteristics, power supply systems, water supply systems, ventilation and heating systems, gas and compressed air installation as well as fire prevention system

  2. Destruction of the Fractional Quantum Hall Effect by Disorder

    Science.gov (United States)

    Laughlin, R. B.

    1985-07-01

    It is suggested that Hall steps in the fractional quantum Hall effect are physically similar to those in the ordinary quantum Hall effect. This proposition leads to a simple scaling diagram containing a new type of fixed point, which is identified with the destruction of the fractional states by disorder. 15 refs., 3 figs.

  3. Improved Hall-Effect Sensors For Magnetic Memories

    Science.gov (United States)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.; Chen, Y. C.; Bhattacharya, Pallab K.

    1993-01-01

    High-electron-mobility sensor films deposited on superlattice buffer (strain) layers. Improved Hall-effect sensors offer combination of adequate response and high speed needed for use in micromagnet/Hall-effect random-access memories. Hall-effect material chosen for use in sensors is InAs.

  4. Digital technology impacts on the Arnhem transfer hall structural design

    NARCIS (Netherlands)

    Van de Straat, R.; Hofman, S.; Coenders, J.L.; Paul, J.C.

    2015-01-01

    The new Transfer Hall in Arnhem is one of the key projects to prepare the Dutch railways for the increased future demands for capacity. UNStudio developed a master plan in 1996 for the station area of which the completion of the Transfer Hall in 2015 will be a final milestone. The Transfer Hall is a

  5. New type of magnetization equipment using a commercial Hall sensor

    Science.gov (United States)

    Nishioka, T.; Sato, N. K.

    2004-05-01

    We have developed a new method of the magnetization measurement using a commercial Hall sensor (Hall magnetometer), which enables us to measure the static magnetization very easily at temperatures as low as about 0.1 K and under pressure. We describe specifications of the Hall magnetometer, and show results of the magnetization measurement for UGe 2 as an example.

  6. Interfacial properties and electron structure of Al/B4C interface: A first-principles study

    Science.gov (United States)

    Xian, Yajiang; Qiu, Ruizhi; Wang, Xin; Zhang, Pengcheng

    2016-09-01

    This research aims at investigating the structural, mechanical and electronic properties of the Al (111)/B4C (0001) interface by first-principles calculations. This model geometry Al (111)/B4C (0001) is chosen because the close-packed planes of Al and B4C have the (111) and (0001) orientation, respectively, and the lattice mismatch is only ∼2.1%. Among four B4C (0001) surfaces with different terminations, our calculation of surface free energies predicted that C-terminated B4C (0001) surface is the most stable one. Relaxed atomic geometries, the work of adhesion and interfacial free energies were calculated for three C-terminated B4C (0001)/Al (111) interfaces with different stacking sequences (top-site, hollow-site, and bridge-site). Results reveal that the relaxed top-site (hollow-site-like) Al/B4C interface has the best adhesion force and also be the most stable. The interfacial electron structure including charge density difference, Bader charge and density of states (DOS) is analyzed to determine the nature of metal/carbide bonding and we find the formation of Alsbnd C bond and possibly the formation of Al4C3 in the interface.

  7. Thermoluminescence and radioluminescence properties of tissue equivalent Cu-doped Li2B4O7 for radiation dosimetry

    International Nuclear Information System (INIS)

    Thermoluminescence (Tl) and radioluminescence (Rl) properties of lithium tetraborate (Li2B4O7) doped with different concentration of copper (0.25, 0.5, 1 wt %) under gamma and beta irradiation has been investigated. The feasibility of using this borate in radiation dosimetry at low doses has been evaluated. Tissue equivalent Li2B4O7 was prepared by solid state reaction using mixing stoichiometric compositions of lithium carbonate (Li2CO3) and boric acid (H3BO3) and a solution of CuCl2 as dopant. The glow curve, of the most efficient copper doped borate (Li2B4O7:Cu 0.5 wt %), shows a main stable peak centered at 225 degrees C and a second low temperature peak centered at 80 degrees C. The low temperature peak disappears completely after 24 hours of storage in darkness and at room temperature or after an annealing at 120 degrees C for 10 seconds. The main peak of the Li2B4O7:Cu remains constant. The Tl response of Li2B4O7:Cu shows good linearity in the analyzed dose range. The stability and repeatability of Rl signals of the borate have been studied and the Li2B4O7:Cu (0.5 wt %) shown the higher Rl emission and a stable and repetitive response. Results show that Li2B4O7:Cu has prospects to be used in gamma and beta radiation dosimetry. (Author)

  8. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators.

    Science.gov (United States)

    Guterding, Daniel; Jeschke, Harald O; Valentí, Roser

    2016-01-01

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions. PMID:27185665

  9. Inertial-Hall effect: the influence of rotation on the Hall conductivity

    Directory of Open Access Journals (Sweden)

    Julio E. Brandão

    2015-01-01

    Full Text Available Inertial effects play an important role in classical mechanics but have been largely overlooked in quantum mechanics. Nevertheless, the analogy between inertial forces on mass particles and electromagnetic forces on charged particles is not new. In this paper, we consider a rotating non-interacting planar two-dimensional electron gas with a perpendicular uniform magnetic field and investigate the effects of the rotation in the Hall conductivity. The rotation introduces a shift and a split in the Landau levels. As a consequence of the break of the degeneracy, the counting of the states fully occupied below the Fermi energy increases, tuning the Hall quantization steps. The rotation also changes the quantum Hall plateau widths. Additionally, we find the Hall quantization steps as a function of rotation at a fixed value of the magnetic field.

  10. Inertial-Hall effect: the influence of rotation on the Hall conductivity

    Science.gov (United States)

    Brandão, Julio E.; Moraes, F.; Cunha, M. M.; Lima, Jonas R. F.; Filgueiras, C.

    Inertial effects play an important role in classical mechanics but have been largely overlooked in quantum mechanics. Nevertheless, the analogy between inertial forces on mass particles and electromagnetic forces on charged particles is not new. In this paper, we consider a rotating non-interacting planar two-dimensional electron gas with a perpendicular uniform magnetic field and investigate the effects of the rotation in the Hall conductivity. The rotation introduces a shift and a split in the Landau levels. As a consequence of the break of the degeneracy, the counting of the states fully occupied below the Fermi energy increases, tuning the Hall quantization steps. The rotation also changes the quantum Hall plateau widths. Additionally, we find the Hall quantization steps as a function of rotation at a fixed value of the magnetic field.

  11. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators

    Science.gov (United States)

    Guterding, Daniel; Jeschke, Harald O.; Valentí, Roser

    2016-01-01

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions. PMID:27185665

  12. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators

    Science.gov (United States)

    Guterding, Daniel; Jeschke, Harald O.; Valentí, Roser

    2016-05-01

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions.

  13. Anomalous Hall Effect for chiral fermions

    CERN Document Server

    Zhang, P -M

    2014-01-01

    Semiclassical chiral fermions manifest the anomalous spin-Hall effect: when put into a pure electric field, they suffer a side jump, analogous to what happens to their massive counterparts in non-commutative mechanics. The transverse shift is consistent with the conservation of the angular momentum. In a pure magnetic field a cork-screw-like, spiraling motion is found.

  14. Hall instability of solar flux tubes

    CERN Document Server

    Pandey, B P

    2011-01-01

    The magnetic network which consists of vertical flux tubes located in intergranular lanes is dominated by Hall drift in the photosphere-lower chromosphere region ($\\lesssim 1\\,{Mm}$). In the internetwork regions, Hall drift dominates above $0.25\\,{Mm}$ in the photosphere and below $2.5\\,{Mm}$ in the chromosphere. Although Hall drift does not cause any dissipation in the ambient plasma, it can destabilise flux tubes and magnetic elements in the presence of an azimuthal shear flow, which destabilises whistler waves. The physical mechanism of this instability is quite simple: the shear flow twists the radial magnetic field and generates azimuthal field; torsional oscillations of the azimuthal field in turn generates the radial field completing a feedback loop. The maximum growth rate of the Hall instability is proportional to the absolute value of the shear gradient and is dependent on the ambient diffusivity. The diffusivity also determines the cut--off wavenumber which is narrower for the stronger fields. We a...

  15. Room acoustic properties of concert halls

    DEFF Research Database (Denmark)

    Gade, Anders Christian

    1996-01-01

    A large database of values of various room acoustic parameters has provided the basis for statistical analyses of how and how much the acoustic properties of concert halls are influenced by their size, shape, and absorption area (as deduced from measured reverberation time). The data have been...

  16. Supersymmetry in the Fractional Quantum Hall Regime

    CERN Document Server

    Sagi, Eran

    2016-01-01

    Supersymmetry (SUSY) is a symmetry transforming bosons to fermions and vice versa. Indications of its existence have been extensively sought after in high-energy experiments. However, signatures of SUSY have yet to be detected. In this manuscript we propose a condensed matter realization of SUSY on the edge of a Read-Rezayi quantum Hall state, given by filling factors of the form $\

  17. Topological quantum numbers in the Hall effect

    OpenAIRE

    Avron, J. E.; Osadchy, D.; Seiler, R.

    2003-01-01

    Topological quantum numbers account for the precise quantization that occurs in the integer Hall effect. In this theory, Kubo's formula for the conductance acquires a topological interpretation in terms of Chern numbers and their non-commutative analog, the Fredholm Indices.

  18. Development and applications of mesoscopic hall microprobes

    NARCIS (Netherlands)

    Novoselov, Konstantin S.

    2004-01-01

    This thesis is devoted to the further development of the local Hall magnetometery technique, and its application for studying ferromagnetic domain wall propagation on the sub-atomic scale. First the ballistic electron transport in a strong, non-uniform magnetic field is discussed. Than a possible in

  19. Moderate positive spin Hall angle in uranium

    Science.gov (United States)

    Singh, Simranjeet; Anguera, Marta; del Barco, Enrique; Springell, Ross; Miller, Casey W.

    2015-12-01

    We report measurements of spin pumping and the inverse spin Hall effect in Ni80Fe20/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni80Fe20 (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 1019 m-2 and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.

  20. Counting Using Hall Algebras I. Quivers

    OpenAIRE

    Fei, Jiarui

    2011-01-01

    We survey some results on counting the rational points of moduli spaces of quiver representations. We then make generalizations to Grassmannians and flags of quiver representations. These results have nice applications to the cluster algebra. Along the way, we use the full Hopf structure of the Hall algebra of a quiver.

  1. Moderate positive spin Hall angle in uranium

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Simranjeet; Anguera, Marta; Barco, Enrique del, E-mail: delbarco@ucf.edu, E-mail: cwmsch@rit.edu [Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States); Springell, Ross [H. H. Will Laboratory, University of Bristol, Bristol BS2 8BS (United Kingdom); Miller, Casey W., E-mail: delbarco@ucf.edu, E-mail: cwmsch@rit.edu [School of Chemistry and Materials Science, Rochester Institute of Technology, Rochester, New York 14623 (United States)

    2015-12-07

    We report measurements of spin pumping and the inverse spin Hall effect in Ni{sub 80}Fe{sub 20}/uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on extended films to inject a spin current from the Ni{sub 80}Fe{sub 20} (permalloy) into the uranium layer, which is then converted into an electric field by the inverse spin Hall effect. Surprisingly, our results suggest a spin mixing conductance of order 2 × 10{sup 19} m{sup −2} and a positive spin Hall angle of 0.004, which are both merely comparable with those of several transition metals. These results thus support the idea that the electronic configuration may be at least as important as the atomic number in governing spin pumping across interfaces and subsequent spin Hall effects. In fact, given that both the magnitude and the sign are unexpected based on trends in d-electron systems, materials with unfilled f-electron orbitals may hold additional exploration avenues for spin physics.

  2. Fractional Quantization of the Hall Effect

    Science.gov (United States)

    Laughlin, R. B.

    1984-02-27

    The Fractional Quantum Hall Effect is caused by the condensation of a two-dimensional electron gas in a strong magnetic field into a new type of macroscopic ground state, the elementary excitations of which are fermions of charge 1/m, where m is an odd integer. A mathematical description is presented.

  3. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators

    OpenAIRE

    Daniel Guterding; Jeschke, Harald O.; Roser Valentí

    2015-01-01

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice M...

  4. Persistent Hall Voltage and Current in the Fractional Quantum Hall Regime

    OpenAIRE

    Kettemann, Stefan

    1997-01-01

    The persistent Hall voltage and current in an isolated annulus in a strong perpendicular magnetic field, at odd inverse filling factor, and in the presence of a weak constriction is obtained as a function of temperature, and flux piercing the annulus. A thermodynamic Hall conductance is found which has a universal value even with back scattering at the constriction. Included are detailed appendices on the bosonization of chiral soliton operators and the derivation of the chiral action, which ...

  5. Quantum Hall fluctuations and evidence for charging in the quantum Hall effect

    OpenAIRE

    Cobden, David H.; Barnes, C H W; Ford, C. J. B.

    1999-01-01

    We find that mesoscopic conductance fluctuations in the quantum Hall regime in silicon MOSFETs display simple and striking patterns. The fluctuations fall into distinct groups which move along lines parallel to loci of integer filling factor in the gate voltage-magnetic field plane. Also, a relationship appears between the fluctuations on quantum Hall transitions and those found at low densities in zero magnetic field. These phenomena are most naturally attributed to charging effects. We argu...

  6. Dry Sliding Tribological Studies of AA6061-B4C-Gr Hybrid Composites

    Science.gov (United States)

    Monikandan, V. V.; Joseph, M. A.; Rajendrakumar, P. K.

    2016-10-01

    The dry sliding behavior of stir-cast AA6061-10 wt.% B4C composites containing 2.5, 5 and 7.5 wt.% graphite particles was studied as a function of applied load, sliding speed and sliding distance on a pin-on-disk tribotester. The wear rate and friction coefficient increased with increase in applied load and sliding distance. The increase in graphite addition reduced the increase in wear rate and friction coefficient in the sliding speed range 2-2.5 m/s. Scanning electron microscopy of the worn pin revealed a graphite tribolayer, and transmission electron microscopy revealed overlapping deformation bands under 30 N applied load. Upon increasing the applied load to 40 N, welded region with fine crystalline structure was formed due to dynamic recrystallization of AA6061 alloy matrix.

  7. Anisotropic magnetic properties of single crystals of SmRh4B4

    International Nuclear Information System (INIS)

    The magnetic susceptibility of single crystals of SmRh4B4 has been measured for two orientations of the crystals with respect to the applied field H. At low temperatures, the easy direction of magnetization is perpendicular to the tetragonal c axis, while for temperatures higher than 73 K, the easy axis of magnetization is parallel to the c axis. The data have been analyzed by including intermediate coupling of the lowest three J manifolds of the Sm/sup 3+/ ion, crystal-field interactions, and conduction-electron polarization effects. The anisotropy crossover is shown to result primarily from a competition between the anisotropy of the crystal-field energy levels in the ground (J = (5/2) manifold and the anisotropy of Van Vleck terms due to mixing of the J = (5/2 and J = 7) / 2 manifolds

  8. Thermoluminescence features of MgB4O7:Tb phosphor

    International Nuclear Information System (INIS)

    In the present work, polycrystalline samples of MgB4O7 doped with terbium at different concentrations were synthesized using the solvent evaporation method. The sample doped with 1 mol% of Tb presented the highest luminescence intensity. The glow curve of the samples showed an intense and well defined TL peak having the maximum on 220 °C and a small shoulder peak at ∼330 °C. TL spectra and fluorescence of 1 mol% doped sample presented a strong Tb3+ emission lines at 489, 545, 588 and 622 nm. The TL dose response was measured over the gamma dose range between 1 and 10 Gy. The relationship between peak intensity and dose was linear and the minimum detectable dose obtained by interpolation taking into account three times the standard deviation of the zero dose reading was 50 μGy

  9. Growth, optical and microstructural properties of PbB4O7 plate crystals

    Science.gov (United States)

    Zaitsev, A. I.; Aleksandrovsky, A. S.; Kozhukhov, A. S.; Pokrovsky, L. D.; Atuchin, V. V.

    2014-11-01

    Centimeter-sized optical quality plate-like PbB4O7 crystals have been grown by Czochralski method. The fundamental absorption edge has been found at 237 nm (corresponding bandgap 5.75 eV) with the distinct sideband protruding up to 300 nm. The crystals are well faceted with the (1 0 0), (0 1 0) and (1 0 1) planes, (1 0 0) surfaces being mostly developed. The etching in diluted nitric acid (5 wt.%) at the temperature of 90 °C have been used to reveal the defect structure and remove melt residuals. The (1 0 0) surface shows the presence of etching pits and twin boundaries. The Kikuchi line pattern and developed microrelief with the roughness of ∼8 nm have been observed by RHEED and AFM, respectively.

  10. B4C solid target boronization of the MST reversed-field pinch

    International Nuclear Information System (INIS)

    A solid rod of hot-pressed boron carbide is being used as the source of boron during boronization of MST. The most striking result of this procedure is the reduction in oxygen contamination of the plasma (O III radiation, characteristic of oxygen at the edge, falls by about a factor of 3 after boronization.). The radiated power fraction drops to about half its initial value. Particle reflux from the wall is also lowered, making density control simpler. The rod (12.7 mm diameter) is inserted into the edge plasma of normal high-power RFP discharges. B4C is ablated from the surface of the rod and deposited in a thin film (a-B/C:H) on the walls and limiters. The energy flux carried by ''superthermal'' (not ''runaway'') electrons at the edge of MST appears to enhance the efficient, non-destructive ablation of the boron carbide rod

  11. Effects of phthalates on the human corneal endothelial cell line B4G12

    DEFF Research Database (Denmark)

    Krüger, Tanja; Cao, Yi; Kjærgaard, Søren K.;

    2012-01-01

    Phthalates are industrial chemicals used in many cosmetics. We evaluated an in vitro model for eye irritancy testing using the human corneal endothelial cell line B4G12. Cell proliferation and toxicity were assessed after exposing to di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2......-ethylhexyl phthalate (DEHP), diisodecyl phthalate (DIDP), di-n-octyl phthalate (DnOP), and di-isononyl phthalate (DINP). Gene expression and secretion of inflammatory cytokines were evaluated after exposure to DBP. Decreased cell proliferation was observed for the phthalates DBP, BBP, and DEHP, and cell...... toxicity was observed for DBP and BBP. Upon DBP exposure at nontoxic concentrations, a significant increased gene expression and cytokine cell secretion were observed for interleukin-1ß (IL-1ß) and IL-8, and also an increased IL-6 secretion was observed. In conclusion, the human corneal endothelial cell...

  12. Parallel Hall effect from 3D single-component metamaterials

    CERN Document Server

    Kern, Christian; Wegener, Martin

    2015-01-01

    We propose a class of three-dimensional metamaterial architectures composed of a single doped semiconductor (e.g., n-Si) in air or vacuum that lead to unusual effective behavior of the classical Hall effect. Using an anisotropic structure, we numerically demonstrate a Hall voltage that is parallel---rather than orthogonal---to the external static magnetic-field vector ("parallel Hall effect"). The sign of this parallel Hall voltage can be determined by a structure parameter. Together with the previously demonstrated positive or negative orthogonal Hall voltage, we demonstrate four different sign combinations

  13. Extrinsic Spin Hall Effect Induced by Iridium Impurities in Copper

    Science.gov (United States)

    Niimi, Y.; Morota, M.; Wei, D. H.; Deranlot, C.; Basletic, M.; Hamzic, A.; Fert, A.; Otani, Y.

    2011-03-01

    We study the extrinsic spin Hall effect induced by Ir impurities in Cu by injecting a pure spin current into a CuIr wire from a lateral spin valve structure. While no spin Hall effect is observed without Ir impurity, the spin Hall resistivity of CuIr increases linearly with the impurity concentration. The spin Hall angle of CuIr, (2.1±0.6)% throughout the concentration range between 1% and 12%, is practically independent of temperature. These results represent a clear example of predominant skew scattering extrinsic contribution to the spin Hall effect in a nonmagnetic alloy.

  14. Accurate micro Hall effect measurements on scribe line pads

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Petersen, Dirch Hjorth; Wang, Fei;

    2009-01-01

    Hall mobility and sheet carrier density are important parameters to monitor in advanced semiconductor production. If micro Hall effect measurements are done on small pads in scribe lines, these parameters may be measured without using valuable test wafers. We report how Hall mobility can...... be extracted from micro four-point measurements performed on a rectangular pad. The dimension of the investigated pad is 400 × 430 ¿m2, and the probe pitches range from 20 ¿m to 50 ¿m. The Monte Carlo method is used to find the optimal way to perform the Hall measurement and extract Hall mobility most...

  15. Compact Reactor

    International Nuclear Information System (INIS)

    Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date

  16. Investigation on microstructural and mechanical properties of B4C–aluminum matrix composites prepared by microwave sintering

    Directory of Open Access Journals (Sweden)

    Ehsan Ghasali

    2015-10-01

    Full Text Available B4C reinforced aluminum composites were fabricated by microwave heating of the mixture of B4C (10, 15 and 20 wt% and aluminum powders at 650, 750, 850 and 950 °C. The effect of different amounts of B4C on the microstructure and mechanical properties of aluminum matrix was examined. The maximum bending (238 ± 10 MPa and compressive strength (330 ± 10 MPa values were measured for composites sintered at 950 and 750 °C, respectively. The maximum hardness (112 Vickers was measured for Al–20 wt% B4C composite sintered at 850 °C. XRD investigations showed the decomposition of boron carbide and also the formation of Al3BC by heating the composites at 850 °C. SEM micrographs showed uniform distribution of reinforcement particles in Al matrix.

  17. Surface activity distribution measurements and establishment of a dose rate map inside the destroyed Chernobyl reactor

    International Nuclear Information System (INIS)

    A Gamma Locator designed for contamination survey inside the reactor hall of the 4th unit of Chernobyl NNP has been developed. The device consists of a detector head and a remote control computer connected by a 150 m long cable. The detector head (dimensions: 500 mm by 500 mm by 400 mm; weight: about 40 kg) is a collimated scintillation gamma detector (the collimation angle is 10 deg.). It is installed on a scanning unit and was placed inside the reactor hall. The Gamma Locator scans all surfaces of the reactor hall with angular steps (≤ 1 deg. vertically as well as horizontally) and the particle fluence from the corresponding direction is recorded. The distance between the device head and the measured surface is instantaneously registered by a laser distance gauge. Inside the collimator there is a small CCD camera which makes it possible to obtain a visible image of the measured surface. The effective surface activity levels are presented in colour on the screen of the control computer. The gamma detector essentially consists of a CsI(TI) scintillator crystal (φ 8 mm in diameter, 2.5 mm in thickness) and a Si photodiode. The detector energy resolution is about 8% for radiation from 137Cs. The exposure dose rate distribution in the reactor hall is estimated from the measured effective surface activities /137Cs is the main gamma emitting isotope inside the reactor hall). The results of dose rate calculations are presented in colour superposed on a drawing of the reactor hall. (au)

  18. Surface activity distribution measurements and establishment of a dose rate map inside the destroyed Chernobyl reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chesnokov, A.V.; Fedin, V.I.; Gulyaev, A.A. [RECOM Ltd., Moscow (Russian Federation)] [and others

    1999-02-01

    A Gamma Locator designed for contamination survey inside the reactor hall of the 4th unit of Chernobyl NNP has been developed. The device consists of a detector head and a remote control computer connected by a 150 m long cable. The detector head (dimensions: 500 mm by 500 mm by 400 mm; weight: about 40 kg) is a collimated scintillation gamma detector (the collimation angle is 10 deg.). It is installed on a scanning unit and was placed inside the reactor hall. The Gamma Locator scans all surfaces of the reactor hall with angular steps ({<=} 1 deg. vertically as well as horizontally) and the particle fluence from the corresponding direction is recorded. The distance between the device head and the measured surface is instantaneously registered by a laser distance gauge. Inside the collimator there is a small CCD camera which makes it possible to obtain a visible image of the measured surface. The effective surface activity levels are presented in colour on the screen of the control computer. The gamma detector essentially consists of a CsI(TI) scintillator crystal ({phi} 8 mm in diameter, 2.5 mm in thickness) and a Si photodiode. The detector energy resolution is about 8% for radiation from {sup 137}Cs. The exposure dose rate distribution in the reactor hall is estimated from the measured effective surface activities ({sup 137}Cs is the main gamma emitting isotope inside the reactor hall). The results of dose rate calculations are presented in colour superposed on a drawing of the reactor hall. (au) 1 tab., 28 ills., 16 refs.

  19. Fabrication of Al5083/B4C surface composite by friction stir processing and its tribological characterization

    OpenAIRE

    Narayana Yuvaraj; Sivanandam Aravindan; Vipin

    2015-01-01

    Improved surface properties with the retainment of bulk properties are necessary for a component for enhanced wear characteristics. Friction stir processing (FSP) is used to produce such surface composites. Fabrication of 5083 aluminum alloy with reinforced layers of boron carbide (B4C) through FSP was carried out. Micro and nano sized B4C particles were used as reinforcements. The friction processed surface composite layer was analyzed through optical and scanning electron microscopical stud...

  20. Thermoelastic properties of ScB2, TiB2, YB4 and HoB4

    DEFF Research Database (Denmark)

    Waskowska, A.; Gerward, L.; Staun Olsen, J.;

    2011-01-01

    High-pressure X-ray diffraction in ScB2, TiB2, YB4 and HoB4 powders and single crystals has been studied using synchrotron radiation as well as conventional X-rays. The experimental results are supported by calculations using density functional theory. ScB2, YB4 and HoB4 are hard materials (bulk ...

  1. Characteristics of electrodeposited RE-Ni-W-B-B4C-MoS2 composite coating

    Institute of Scientific and Technical Information of China (English)

    马克毅; 郭忠诚; 朱晓云; 徐瑞东

    2003-01-01

    The high temperature oxidation resistance of RE-Ni-W-B-B4C-MoS2 composite coating, the effects of electrodeposition conditions on the morphologies of the coating and the effect of heat treatment temperature on its hardness, abrasion resistance and phase structure were investigated by using scanning electron microscope(SEM), X-ray diffractometer, microhardness tester and abrasion machine. The results show that the oxidation degree of RE-Ni-W-B-B4C-MoS2 composite coating is small when the temperature is lower than 700 ℃, but it increases sharply when the temperature is higher than 700 ℃. The hardness of RE-Ni-W-B-B4C-MoS2 composite coating increases with increasing heat treatment temperature, it comes up to the maximum value at 400 ℃,but it decreases gradually if the temperature rises continuously. The most favourable abrasion resistance was attained after RE-Ni-W-B-B4C-MoS2 composite coating being heat treated at 400 ℃. Without heat treating, it is mainly amorphous and partially crystallized, but wholly crystallized after being heat treated at 500 ℃. RE in the composite coating is in the form of CeO2 and additions of CeO2 and B4C can enhance the thermostability of RE-Ni-W-B-B4C-MoS2 composite coating.

  2. Microstructure and Dry-Sliding Wear Behavior of B4C Ceramic Particulate Reinforced Al 5083 Matrix Composite

    Directory of Open Access Journals (Sweden)

    Qian Zhao

    2016-09-01

    Full Text Available B4C ceramic particulate–reinforced Al 5083 matrix composite with various B4C content was fabricated successfully via hot-press sintering under Argon atmosphere. B4C particles presented relative high wettability, bonding strength and symmetrical distribution in the Al 5083 matrix. The hardness value, friction coefficient and wear resistance of the composite were higher than those of the Al 5083 matrix. The augment of the B4C content resulted in the increase of the friction coefficient and decrease of the wear mass loss, respectively. The 30 wt % B4C/Al 5083 composite exhibited the highest wear resistance. At a low load of 50 N, the dominant wear mechanisms of the B4C/Al 5083 composite were micro-cutting and abrasive wear. At a high load of 200 N, the dominant wear mechanisms were micro-cutting and adhesion wear associated with the formation of the delamination layer which protected the composite from further wear and enhanced the wear resistance under the condition of high load.

  3. Expression of EphB4 and EphrinB2 in retinoblastoma and their significance%视网膜母细胞瘤中EphB4和EphrinB2的表达及意义

    Institute of Scientific and Technical Information of China (English)

    耿祥娥; 赵玉斌; 张少华; 吕杰; 徐治伟; 王金清

    2012-01-01

    目的 探讨EphB4和EphrinB2的蛋白在视网膜母细胞瘤中的表达及其意义.方法 应用免疫组织化学SP法测定10例正常视网膜组织和40例视网膜母细胞瘤标本中EphB4和EphrinB2的表达水平,分析其与性别、临床分期、分化程度和视神经浸润的关系.结果(1)EphB4和EphrinB2蛋白表达的阳性率,在正常视网膜组织中分别为5%和2.5%,40例视网膜母细胞瘤标本中分别为77.5%和67.5%.EphB4和EphrinB2在视网膜母细胞瘤组织中的阳性率与显著高于正常视网膜组织中的阳性率(P<0.05).(2)EphB4和EphrinB2的蛋白在视网膜母细胞瘤的阳性表达率与肿瘤组织的临床分期、分化程度及视神经浸润显著相关(P<0.05).(3)EphB4和EphrinB2的蛋白在视网膜母细胞瘤组织中的阳性表达显著相关(P<0.05).结论 EphB4和EphrinB2可能在视网膜母细胞瘤的发生和发展过程中起重要作用,可作为评价视网膜母细胞瘤的浸润及预后的标志物.%Objective To investigate the protein expressions of EphB4 and EphrinB2 in retinoblastoma and to study their significance.Methods The expression of EphB4 and EphrinB2 was examined immunohistochemistrically by SP method in tissues of 10 normal retina and 40 patients with retinoblastoma and to study their relationship with gender,clinical stage,differentiation and optic nerve infiltration.Results 1.The protein expression of EphB4 and EphrinB2 observed in the normal tissues of retina was 5% and 2.5% respectively.In the 40 retinoblastoma cases,the positive rate of them was 77.5% and 67.5% respectively.The positive rate of EphB4 and EphrinB2 in retinoblastoma was higher than that in the normal retina(P<0.05).2.The positive expression of EphB4 and EphrinB2 protein were associated with clinical stage,differentiation and optic nerve infiltration(P<0.05).3.The positive expression of EphB4 and EphrinB2 protein in retinoblastoma was positively correlated(P<0.05).Conclusions EphB

  4. NEUTRONIC REACTOR

    Science.gov (United States)

    Anderson, H.L.

    1960-09-20

    A nuclear reactor is described comprising fissionable material dispersed in graphite blocks, helium filling the voids of the blocks and the spaces therebetween, and means other than the helium in thermal conductive contact with the graphite for removing heat.

  5. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  6. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  7. NUCLEAR REACTOR

    Science.gov (United States)

    Anderson, C.R.

    1962-07-24

    A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)

  8. Nuclear reactor

    International Nuclear Information System (INIS)

    In order to reduce neutron embrittlement of the pressue vessel of an LWR, blanked off elements are fitted at the edge of the reactor core, with the same dimensions as the fuel elements. They are parallel to each other, and to the edge of the reactor taking the place of fuel rods, and are plates of neutron-absorbing material (stainless steel, boron steel, borated Al). (HP)

  9. Coexistence of qnrB4 and qnrS1 in a clinical strain of Klebsiella pneumoniae

    Institute of Scientific and Technical Information of China (English)

    Fu-pin HU; Xiao-gang XU; De-mei ZHU; Ming-gui WANG

    2008-01-01

    Aim:To identify the location and the relationship,and to analyze the genetic background of 2 plasmid-mediated quinolone resistance genes,qnrB4 and qnrS1,carried by a clinical strain of Klebsiella pneumoniae (Kpneumoniae).Methods:The plasmids carrying qnrB4 or qnrS1 were identified by Southern blotting.A HindIII fragment containing qnrB4 or qnrS1 was cloned into plasmid puc 18 and sequenced.Results:qnrB4 and qnrS1 were located on 2 different plasmids,pHS7 and pHSS,and were 180 and 45 kb in size,respectively.A transconjugant carrying plasmid pHS7 bearing qnrB4 and another transconjugant carrying pHS9 bearing qnrB4 and qnrS1 were obtained by conjugation.Plasmid pHS8 bearing qnrSl was also transferred to J53 by transformation.The ciprofloxacin minimal inhibitory concentrations (MIC) for J53 transconjugants or the transformant car-rying qnrB4 only,qnrS1 only,and both qnrB4 and qnrS1 were 0.19,0.25,and 0.25 mg/L,respectively,while the parent clinical strain of Kpneumoniae had a MIC of 0.75 mg/L.qnrB4 was located in a sull-type integron with blaDHA-1,ampR and psp genes in upstream and insertion sequence IS26,and sap genes in downstream of qnrB4,qnrS1 was not located in an integron,but IS26 was found both upstream and downstream,and IS2 was found directly upstream of qnrS1.Conclusion:qnrB and qnrS can be harbored simultaneously by a single clinical strain of K pneumoniae.These 2 genes are carried by 2 different plasmids and have different genetic environments in plasmid DNA structure.

  10. Assessment of elevator rope using Hall Sensor

    International Nuclear Information System (INIS)

    Defect detection of wire rope for an elevator was investigated through the measurement of magnetic flux leakage. The types of defect usually found in wire rope categorized such as inner and outer wire breakage and wear. The specimens that has artificial defects were magnetized via permanent magnet, and measurement of magnetic flux leakage on the defects was performed with Hall sensor. In wire broken model, a defect smaller than 0.4 mm and 1 mm in depth on outer and inner wire rope, respectively, could be detected well. In wear model, smaller defect could not be detected clearly, however, appearance of changing of total magnetic flux during magnetic pole of the sensor passing through a defect 0.2 mm in depth at 4 mm or above width could make possible to detect it. From the results, the measurement via Hall sensor might be useful tool for defect detection of wire rope.

  11. Assesment of elevator rope using hall sensor

    International Nuclear Information System (INIS)

    Defect detection of wire rope for an elevator was investigated through the measurement of magnetic flux leakage. The types of defect usually found in wire rope categorized such as inner and outer wire breakage and wear. The specimens that has artificial defects were magnetized via permanent magnet, and measurement of magnetic flux leakage on the defects was performed with Hall sensor. In wire broken model, a defect smaller than 0.4mm and 1mm in depth on outer and inner wire rope, respectively, could be detected well. In wear model, smaller defect could not be detected clearly, however, appearance of changing of total magnetic flux during magnetic pole of the sensor passing through a defect 0.2mm in depth at 4mm or above width could make possible to detect it. From the results, the measurement via Hall sensor might be useful tool for defect detection of wire rope.

  12. Hall Scrambling on Black Hole Horizon

    CERN Document Server

    Fischler, Willy

    2015-01-01

    We explore the effect of the electrodynamics $\\theta$-angle on the macroscopic properties of black hole horizons. Using only classical Einstein-Maxwell-Chern-Simons theory in (3+1)-dimensions, in the form of the membrane paradigm, we show that in the presence of the $\\theta$-term, a black hole horizon behaves as a Hall conductor, for an observer hovering outside. We study how localized perturbations created on the stretched horizon scramble on the horizon by dropping a charged particle. We show that the $\\theta$-angle affects the way perturbations scramble on the horizon, in particular, it introduces vortices without changing the scrambling time. This Hall scrambling of information is also expected to occur on cosmological horizons.

  13. Judy Estes Hall (1940-2015).

    Science.gov (United States)

    Sammons, Morgan T; Boucher, Andrew

    2016-01-01

    Presents an obituary for Judy Estes Hall, who passed away on November 24, 2015. Hall served as the Executive Officer of the National Register of Health Service Psychologists until her retirement in 2013. She is a recognized expert in the development of education and training standards for the profession of psychology, she also made significant contributions in the field of international psychology, where she was a renowned expert in cross-national credentialing and an advocate for commonality in licensing standards. She was the coauthor of one edited volume and author of more than 60 journal articles, book chapters, and professional publications. A passionate advocate for the advancement of women in psychology, a devoted mother and grandmother, a connoisseur of wine and international traveler extraordinaire, she touched the personal and professional lives of many. (PsycINFO Database Record PMID:27504582

  14. Judy Estes Hall (1940-2015).

    Science.gov (United States)

    Sammons, Morgan T; Boucher, Andrew

    2016-01-01

    Presents an obituary for Judy Estes Hall, who passed away on November 24, 2015. Hall served as the Executive Officer of the National Register of Health Service Psychologists until her retirement in 2013. She is a recognized expert in the development of education and training standards for the profession of psychology, she also made significant contributions in the field of international psychology, where she was a renowned expert in cross-national credentialing and an advocate for commonality in licensing standards. She was the coauthor of one edited volume and author of more than 60 journal articles, book chapters, and professional publications. A passionate advocate for the advancement of women in psychology, a devoted mother and grandmother, a connoisseur of wine and international traveler extraordinaire, she touched the personal and professional lives of many. (PsycINFO Database Record

  15. Hall magnetohydrodynamics: Conservation laws and Lyapunov stability

    Energy Technology Data Exchange (ETDEWEB)

    Holm, D.D.

    1987-05-01

    Hall electric fields produce circulating mass flow in confined ideal-fluid plasmas. The conservation laws, Hamiltonian structure, equilibrium state relations, and Lyapunov stability conditions are presented here for ideal Hall magnetohydrodynamics (HMHD) in two and three dimensions. The approach here is to use the remarkable array of nonlinear conservation laws for HMHD that follow from its Hamiltonian structure in order to construct explicit Lyapunov functionals for the HMHD equilibrium states. In this way, the Lyapunov stability analysis provides classes of HMHD equilibria that are stable and whose linearized initial-value problems are well posed (in the sense of possessing continuous dependence on initial conditions). Several examples are discussed in both two and three dimensions.

  16. Three halls for music performance in Chile

    Science.gov (United States)

    Delannoy, Jaime; Heuffemann, Carolina; Ramirez, Daniel; Galvez, Fernando

    2002-11-01

    The primary purpose of this work was to investigate about the present acoustic conditions of used architectonic spaces in Santiago of Chile for orchestras of classic music performance. The studied halls were three: Aula Magna Universidad de Santiago, Teatro Municipal de Nunoa, and Teatro Baquedano. The used methodology was based on studies made by L. Beranek, M. Barron, among others, in concert halls worldwide. As it guides, for the measurement procedure, physical parameters RT, EDT, C50, C80, LF, BR, G, U50 were evaluated according to norm ISO 3382. On the other hand, it has been defined, to proposal way, a questionnaire of subjective valuation directed to musicians, specialized conductors, and listeners.

  17. Vortex Physics in the Quantum Hall Bilayer

    Science.gov (United States)

    Fertig, H. A.; Murthy, Ganpathy

    2013-06-01

    There exists a strong analogy between the quantum Hall bilayer system at total filling factor ν = 1 and a thin film superfluid, in which the groundstate is described as a condensate of particle-hole pairs. The analogy draws support from experiments which display near dissipationless transport properties at low temperatures. However dissipation is always present at any accessible temperature, suggesting that in a proper description, unpaired vortex-like excitations must be present. The mechanism by which this happens remains poorly understood. A key difference between the quantum Hall bilayer and simpler thin-film superfluids is that the vortices, more properly called merons in the former context, are charged objects. We demonstrate that a model in which disorder induces merons in the groundstate, through coupling to this charge, can naturally explain many of the observed imperfect superfluid properties...

  18. Hall magnetohydrodynamics: Conservation laws and Lyapunov stability

    International Nuclear Information System (INIS)

    Hall electric fields produce circulating mass flow in confined ideal-fluid plasmas. The conservation laws, Hamiltonian structure, equilibrium state relations, and Lyapunov stability conditions are presented here for ideal Hall magnetohydrodynamics (HMHD) in two and three dimensions. The approach here is to use the remarkable array of nonlinear conservation laws for HMHD that follow from its Hamiltonian structure in order to construct explicit Lyapunov functionals for the HMHD equilibrium states. In this way, the Lyapunov stability analysis provides classes of HMHD equilibria that are stable and whose linearized initial-value problems are well posed (in the sense of possessing continuous dependence on initial conditions). Several examples are discussed in both two and three dimensions

  19. Fast Camera Imaging of Hall Thruster Ignition

    International Nuclear Information System (INIS)

    Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 (micro)s. The cathode introduces azimuthal asymmetry, which persists for about 30 (micro)s into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correction and drag compensation. The advantage of plasma thrusters over conventional chemical thrusters is that the exhaust energies are not limited by chemical energy to about an electron volt. For xenon Hall thrusters, the ion exhaust velocity can be 15-20 km/s, compared to 5 km/s for a typical chemical thruster.

  20. Anomalous Hall effect in Weyl superconductors

    Science.gov (United States)

    Bednik, G.; Zyuzin, A. A.; Burkov, A. A.

    2016-08-01

    We present a theory of the anomalous Hall effect in a topological Weyl superconductor with broken time reversal symmetry. Specifically, we consider a ferromagnetic Weyl metal with two Weyl nodes of opposite chirality near the Fermi energy. In the presence of inversion symmetry, such a metal experiences a weak-coupling Bardeen–Cooper–Schrieffer instability, with pairing of parity-related eigenstates. Due to the nonzero topological charge, carried by the Weyl nodes, such a superconductor is necessarily topologically nontrivial, with Majorana surface states coexisting with the Fermi arcs of the normal Weyl metal. We demonstrate that, surprisingly, the anomalous Hall conductivity of such a superconducting Weyl metal coincides with that of a nonsuperconducting one, under certain conditions, in spite of the nonconservation of charge in a superconductor. We relate this to the existence of an extra (nearly) conserved quantity in a Weyl metal, the chiral charge.

  1. Infinite symmetry in the quantum Hall effect

    Directory of Open Access Journals (Sweden)

    Lütken C.A.

    2014-04-01

    Full Text Available The new states of matter and concomitant quantum critical phenomena revealed by the quantum Hall effect appear to be accompanied by an emergent modular symmetry. The extreme rigidity of this infinite symmetry makes it easy to falsify, but two decades of experiments have failed to do so, and the location of quantum critical points predicted by the symmetry is in increasingly accurate agreement with scaling experiments. The symmetry severely constrains the structure of the effective quantum field theory that encodes the low energy limit of quantum electrodynamics of 1010 charges in two dirty dimensions. If this is a non-linear σ-model the target space is a torus, rather than the more familiar sphere. One of the simplest toroidal models gives a critical (correlation length exponent that agrees with the value obtained from numerical simulations of the quantum Hall effect.

  2. Music hall Markneukirchen; Musikhalle in Markneukirchen

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-01-01

    The article presents the new building of the music hall Markneukirchen. From the planned use of the building result very high demands on the ventilation system in order to keep to a sound power level of less than 30 dB(A) in the hall. The building services are dealt with using numerous flowsheets and diagrams: Heat supply, ventilation system, sanitary system, building management, instrumentation and control, electric and lighting systems. (BWI) [Deutsch] Der vorliegende Beitrag stellt den Neubau der Musikhalle Markneukirchen vor. Durch das Nutzungskonzept ergeben sich fuer die Einhaltung eines Schalleistungspegels von weniger als 30 dB(A) im Saalbereich an die Lueftungsanlage sehr hohe Ansprueche. Es werden die raumlufttechnischen Anlagen anhand zahlreicher Flussbilder und Abbildungen vorgestellt: Waermeversorgung, Lueftungstechnik, Sanitaertechnik, Gebaeudeleit- und MSR-Technik, Elektro- und Lichttechnik. (BWI)

  3. PMCA4 (ATP2B4 mutation in familial spastic paraplegia.

    Directory of Open Access Journals (Sweden)

    Miaoxin Li

    Full Text Available Familial spastic paraplegia (FSP is a heterogeneous group of disorders characterized primarily by progressive lower limb spasticity and weakness. More than 50 disease loci have been described with different modes of inheritance. In this study, we identified a novel missense mutation (c.803G>A, p.R268Q in the plasma membrane calcium ATPase (PMCA4, or ATP2B4 gene in a Chinese family with autosomal dominant FSP using whole-exome sequencing and confirmed with Sanger sequencing. This mutation co-segregated with the phenotype in the six family members studied and is predicted to be pathogenic when multiple deleteriousness predictions were combined. This novel R268Q mutation was not present in over 7,000 subjects in public databases, and over 1,000 Han Chinese in our database. Prediction of potential functional consequence of R268Q mutation on PMCA4 by computational modeling revealed that this mutation is located in protein aggregation-prone segment susceptible to protein misfolding. Analysis for thermodynamic protein stability indicated that this mutation destabilizes the PMCA4 protein structure with higher folding free energy. As PMCA4 functions to maintain neuronal calcium homeostasis, our result showed that calcium dysregulation may be associated with the pathogenesis of FSP.

  4. Machinability Studies on Turning Al 6061alloy with 10% Reinforcement of B4C on MMC

    Directory of Open Access Journals (Sweden)

    Srivathsan A.

    2016-01-01

    Full Text Available Aluminum Boron Carbide Metal Matrix Composites (Al-MMC have revolutionized aeronautical and automobile industries, in the recent times due to their exceptional mechanical and physical properties. However it is seen that the machinability of these composites is greatly reduced by the hardness of constituent reinforcement particles. Moreover these constituent reinforcement particles serve as disadvantage by increasing tool wear accompanying undesirable depression in life of tool. This paper presents the experimental investigations on turning of Al6061 matrix metal reinforced with 10 % by weight of boron carbide (B4Cp particles - which was fabricated using Stir casting method. Fabricated samples are turned on medium duty lathe of 2kW spindle power with Polycrystalline Diamond (PCD inserts of 1500 grade at various cutting conditions by varying parameters. Hence, parameters such as power consumed by main spindle, machined surface roughness and tool wear are studied and recorded. Furthermore, study results are supported using concurring images obtained from Scanning Electron Microscopy (SEM. It is observed that surface finish and power consumed for 1500 grade insert are comparatively better at higher cutting speeds. Additionally it is observed that tool wear is strongly dependent on abrasive hard reinforcement particles.

  5. Leukotriene B4 and tumor necrosis factor release from leukocytes: effect of peritoneal dialysate.

    Science.gov (United States)

    Jörres, A; Jörres, D; Gahl, G M; Kessel, M; Müller, C; Köttgen, E; Serke, S; Schulz, E; Mahiout, A

    1991-01-01

    The effect of peritoneal dialysate on the capacity of peripheral blood polymorphonuclear (PMNL) and mononuclear leukocytes (MNC) to release leukotriene B4 (LTB4) and tumor necrosis factor alpha (TNF alpha) was investigated in vitro. Following density gradient separation, aliquots of 5 x 10(6) PMNL or MNC were incubated in peritoneal dialysis fluid containing 1.5% glucose or Hanks' buffer (= control) for 1-2 h at 37 degrees C. TNF alpha and LTB4 production was stimulated with Escherichia coli lipopolysaccharide (LPS) and calcium ionophore A23187, respectively. MNC incubated in buffer and LPS produced (mean +/- SD) 1,006 +/- 522 pg TNF alpha/5 x 10(6) cells; no significant amounts of TNF alpha were detectable in the presence of dialysate. An inhibition of TNF alpha release was also observed in MNC exposed to bicarbonate-buffered dialysates (pH 7.40) and 4.25% and 1.5% glucose solution with physiologic osmolality. Incubation of PMNL in Hanks' buffer followed by A23187 stimulation led to production of 29.1 +/- 19.2 ng LTB4/5 x 10(6) cells, whereas glucose-incubated cells were refractory to ionophore stimulation (less than 0.1 ng LTB4/5 x 10(6) cells). The failure of dialysate-exposed leukocytes to release inflammatory mediators in response to adequate stimuli may contribute to the impairment of cellular host defense in the setting of continuous ambulatory peritoneal dialysis.

  6. Optimization Conditions of Production Fibrinolytic Enzyme from Bacillus lichniformis B4 Local Isolate

    Directory of Open Access Journals (Sweden)

    Essam F. Al-Juamily

    2012-12-01

    Full Text Available The study was conducted with the aim to found local isolate belongs to Bacillus lichniformis to produce fibrinolytic enzyme with highest activity under optimal conditions. Forty-five local isolates belongs to the genus Bacillus lichniformis were selected for production of fibrinolytic enzyme (E.C. 3.4.. The isolate Bacillus lichniformis B4 was selected due to its high productivity of fibrinolytic enzyme. The optimal conditions for fibrinolytic enzyme production were determined, using a solid Lentils medium (activity 25.25 U/mL at pH 7.2 (65.381 U/mL, 105 cell/g wet weight (19.185 U/mL 48 h as incubation time (15.766 U/mL and shaking incubator (95.992 U/mL were the optimal culture condition for the production of greatest amount enzyme with highest activity. The optimal carbon and nitrogen sources were mannitol and peptone or soya peptone with activity 44 and 50 unit/mL, respectively.

  7. Neutrophil swarming toward Cryptococcus neoformans is mediated by complement and leukotriene B4.

    Science.gov (United States)

    Sun, Donglei; Shi, Meiqing

    2016-09-01

    Swarming behavior of neutrophils has been noticed in both sterile injury and infection models and the mechanisms are being unveiled. So far, no in vitro model has been established to study neutrophil swarming to microbes. In the current study, using live-cell imaging, we observed in vitro neutrophil swarming toward Cryptococcus neoformans, a fungal pathogen causing human meningoencephalitis. Complement C3 and CD11b expression are essential for neutrophils to form cell swarms surrounding C. neoformans. Leukotriene B4 (LTB4) was quickly released by neutrophils during their interactions with C. neoformans. Blockade of LTB4 synthesis inhibited the swarming response to C. neoformans. Importantly, blockade of LTB4 synthesis also significantly reduced neutrophil recruitment in the lung vasculature of mice infected intravenously with C. neoformans, demonstrating a critical role of LTB4 in intravascular neutrophil swarming during infection. Together, this is the first report of neutrophil dynamics of swarming toward a microorganism in vitro, mediated by complement and LTB4. PMID:27402276

  8. Heterozygous mutations in HSD17B4 cause juvenile peroxisomal D-bifunctional protein deficiency

    Science.gov (United States)

    Amor, David J.; Marsh, Ashley P.L.; Storey, Elsdon; Tankard, Rick; Gillies, Greta; Delatycki, Martin B.; Pope, Kate; Bromhead, Catherine; Leventer, Richard J.; Bahlo, Melanie

    2016-01-01

    Objective: To determine the genetic cause of slowly progressive cerebellar ataxia, sensorineural deafness, and hypergonadotropic hypogonadism in 5 patients from 3 different families. Methods: The patients comprised 2 sib pairs and 1 sporadic patient. Clinical assessment included history, physical examination, and brain MRI. Linkage analysis was performed separately on the 2 sets of sib pairs using single nucleotide polymorphism microarrays, followed by analysis of the intersection of the regions. Exome sequencing was performed on 1 affected patient with variant filtering and prioritization undertaken using these intersected regions. Results: Using a combination of sequencing technologies, we identified compound heterozygous mutations in HSD17B4 in all 5 affected patients. In all 3 families, peroxisomal D-bifunctional protein (DBP) deficiency was caused by compound heterozygosity for 1 nonsense/deletion mutation and 1 missense mutation. Conclusions: We describe 5 patients with juvenile DBP deficiency from 3 different families, bringing the total number of reported patients to 14, from 8 families. This report broadens and consolidates the phenotype associated with juvenile DBP deficiency.

  9. Scintillation characteristics of undoped and Cu+-doped Li2B4O7 single crystals

    CERN Document Server

    Kobayashi, Masaaki; Senguttuvan, Nachimuthu

    2015-01-01

    Scintillation characteristics of undoped and Cu+-doped lithium tetraborate Li2B4O7 (LTB) were studied including optical transmittance, photoluminescence, radioluminescence for X- and gamma-rays, alpha/gamma ratio, and decay kinetics. The total time-integrated LYs in undoped and Cu+-doped LTB for X-rays are ~600 and ~760 ph/MeV (photons/MeV), respectively. The decay kinetics in undoped and Cu+-doped LTB are similar to each other. Typical decay spectra for pulsed X-rays can be fitted with four exponentials: for fast (t1~0.8 ns, t2~25-50 ns), medium (t3~300-400 ns), and slow (t4~20-30 ms) components. The slow component occupies about 60% of the total LY, while the fast ones less than 10%. The 10-90% rise time was 163 ps. The alpha/gamma ratio was 0.18 for external 241Am alpha-rays. The obtained increase in LY due to Cu+ doping remains modest. The Cu+-induced emission contains both fast and slow components, requiring further studies of the emission mechanism to explain the fast component.

  10. A-site ordered quadruple perovskite oxides AA03B4O12

    Institute of Scientific and Technical Information of China (English)

    龙有文

    2016-01-01

    The A-site ordered perovskite oxides with chemical formula AA03B4O12 display many intriguing physical properties due to the introduction of transition metals at both A0 and B sites. Here, research on the recently discovered intermetallic charge transfer occurring between A0-site Cu and B-site Fe ions in LaCu3Fe4O12 and its analogues is reviewed, along with work on the magnetoelectric multiferroicity observed in LaMn3Cr4O12 with cubic perovskite structure. The Cu–Fe intermetallic charge transfer (LaCu3+3 Fe3+4 O12→LaCu2+3 Fe3.75+4 O12) leads to a first-order isostructural phase transition accompanied by drastic variations in magnetism and electrical transport properties. The LaMn3Cr4O12 is a novel spin-driven multiferroic system with strong magnetoelectric coupling effects. The compound is the first example of cubic perovskite multiferroics to be found. It opens up a new arena for studying unexpected multiferroic mechanisms.

  11. Metabolism in vitro of leukotriene B4 in blood of normal subjects and asthmatic patients

    International Nuclear Information System (INIS)

    The metabolism of exogenous leukotriene B4 (LTB4) was investigated in venous blood obtained from normal and asthmatic subjects. Using specific radioimmunoassay (RIA) and reverse-phase high performance liquid chromatography (RP-HPLC) techniques we have demonstrated that LTB4 is relatively stable during a 2 hr incubation period at 37 degrees C in our system in vitro. Nevertheless, chromatographic analysis revealed the presence of two products which had retention times identical to 20-hydroxy LTB4 (20-0H LTB4) and 20-carboxy LTB4 (20-C00H LTB4) in which the dicarboxylic derivative was the main metabolite present after 15 min incubation. The amount of LTB4 and its w-oxidation products observed after a 2 hr incubation period was 73% and 24% respectively. There was no basal release of LTB4 from blood. The appearance of these oxidative products was totally suppressed at 4 degrees C and with incubations performed with either venous plasma or Hartmann's control. No significant difference was observed in substrate metabolism between normal and asthmatic subjects. Our results demonstrate that LTB4 is slowly degraded in human whole blood through a cellular dependent process of w-oxidation which may be an important pathway for regulating the availability of this potent biologically active substance

  12. Microstructure and mechanical properties of pulsed electric current sintered B4C-TiB2 composites

    International Nuclear Information System (INIS)

    Research highlights: → Fast densification of B4C-TiB2 particulate composites. → Oxide impurity removal by evaporation. → Judiciously controlled loading cycle during pulsed electric current sintering. → High strength micrometer sized B4C-TiB2 composites. - Abstract: Monolithic B4C, TiB2 and B4C-TiB2 particulate composites were consolidated without sintering additives by means of pulsed electric current sintering in vacuum. Sintering studies on B4C-TiB2 composites were carried out to reveal the influence of the pressure loading cycle during pulsed electrical current sintering (PECS) on the removal of oxide impurities, i.e. boron oxide and titanium oxide, hereby influencing the densification behavior as well as microstructure evolvement. The critical temperature to evaporate the boron oxide impurities was determined to be 2000 deg. C. Fully dense B4C-TiB2 composites were achieved by PECS for 4 min at 2000 deg. C when applying the maximum external pressure of 60 MPa after volatilization of the oxide impurities, whereas a relative density of 95-97% was obtained when applying the external pressure below 2000 deg. C. Microstructural analysis showed that B4C and TiB2 grain growth was substantially suppressed due to the pinning effect of the secondary phase and the rapid sintering cycle, resulting in micrometer sized and homogeneous microstructures. Excellent properties were obtained for the 60 vol% TiB2 composite, combining a Vickers hardness of 29 GPa, a fracture toughness of 4.5 MPa m1/2 and a flexural strength of 867 MPa, as well as electrical conductivity of 3.39E+6 S/m.

  13. Protonated Dipeptide Losses from b 5 and b 4 Ions of Side Chain Hydroxyl Group Containing Pentapeptides

    Science.gov (United States)

    Atik, A. Emin; Yalcin, Talat

    2013-10-01

    In this study, C-terminal protonated dipeptide eliminations were reported for both b 5 and b 4 ions of side chain hydroxyl group (-OH) containing pentapeptides. The study utilized the model C-terminal amidated pentapeptides having sequences of XGGFL and AXVYI, where X represents serine (S), threonine (T), glutamic acid (E), aspartic acid (D), or tyrosine (Y) residue. Upon low-energy collision-induced dissociation (CID) of XGGFL (where X = S, T, E, D, and Y) model peptide series, the ions at m/z 279 and 223 were observed as common fragments in all b 5 and b 4 ion (except b 4 ion of YGGFL) mass spectra, respectively. By contrast, peptides, namely SMeGGFL-NH2 and EOMeGGFL-NH2, did not show either the ion at m/z 279 or the ion at m/z 223. It is shown that the side chain hydroxyl group is required for the possible mechanism to take place that furnishes the protonated dipeptide loss from b 5 and b 4 ions. In addition, the ions at m/z 295 and 281 were detected as common fragments in all b 5 and b 4 ion (except b 4 ion of AYVYI) mass spectra, respectively, for AXVYI model peptide series. The MS4 experiments exhibited that the fragment ions at m/z 279, 223, 295, and 281 entirely reflect the same fragmentation behavior of [M + H]+ ion generated from commercial dipeptides FL-OH, GF-OH, YI-OH, and VY-OH. These novel eliminations reported here for b 5 and b 4 ions can be useful in assigning the correct and reliable peptide sequences for high-throughput proteomic studies.

  14. Physical principles underlying the quantum Hall effect

    OpenAIRE

    Bieri, Samuel; Froehlich, Juerg

    2010-01-01

    In this contribution, we present an introduction to the physical principles underlying the quantum Hall effect. The field theoretic approach to the integral and fractional effect is sketched, with some emphasis on the mechanism of electromagnetic gauge anomaly cancellation by chiral degrees of freedom living on the edge of the sample. Applications of this formalism to the design and theoretical interpretation of interference experiments are outlined.

  15. Multipole expansion in the quantum hall effect

    Science.gov (United States)

    Cappelli, Andrea; Randellini, Enrico

    2016-03-01

    The effective action for low-energy excitations of Laughlin's states is obtained by systematic expansion in inverse powers of the magnetic field. It is based on the W- infinity symmetry of quantum incompressible fluids and the associated higher-spin fields. Besides reproducing the Wen and Wen-Zee actions and the Hall viscosity, this approach further indicates that the low-energy excitations are extended objects with dipolar and multipolar moments.

  16. Homotopy arguments for quantized Hall conductivity

    CERN Document Server

    Richter, T

    2002-01-01

    Using the strong localization bounds obtained by the Aizenman-Molcanov method for a particle in a magnetic field and a disordered potential, we show that the zero-temperature Hall conductivity of a gas of such particles is quantized and constant as long as both Fermi energy and disorder coupling parameter vary in a region of strong localization of the corresponding two-dimensional phase diagram.

  17. Viscoelastic-electromagnetism and Hall viscosity

    OpenAIRE

    Hidaka, Yoshimasa; Hirono, Yuji(Department of Physics, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan); Kimura, Taro; MINAMI, Yuki

    2012-01-01

    We introduce a kind of electromagnetism, which we call viscoelastic-electromagnetism, to investigate viscoelastic transport phenomena. It is shown that Cartan's formalism of general relativity is essential for viscoelastic theory, and then the corresponding electric and magnetic fields are regarded as a velocity gradient and a Burgers vector density, respectively. As an application of this formalism, the Streda formula for the Hall viscosity is obtained.

  18. SERVIR Town Hall - Connecting Space to Village

    Science.gov (United States)

    Limaye, Ashutosh S.; Searby, Nancy D.; Irwin, Daniel; Albers, Cerese

    2013-01-01

    SERVIR, a joint NASA-USAID project, strives to improve environmental decision making through the use of Earth observations, models, and geospatial technology innovations. SERVIR connects these assets with the needs of end users in Mesoamerica, East Africa, and Hindu Kush-Himalaya regions. This Town Hall meeting will engage the AGU community by exploring examples of connecting Space to Village with SERVIR science applications.

  19. SPS beam to the West Hall

    CERN Multimedia

    1976-01-01

    One of the two target stations feeding the West Hall (see Annual Report 1976). After the proton beam was split into three branches, the outer two were directed on to targets in the cast iron shielding box, the centre one passing through the box to another target station downstream. Five different targets could be put in each beam, controlled by the mechanism seen on top.

  20. Fractional Quantum Hall States in Graphene

    CERN Document Server

    Jellal, Ahmed

    2008-01-01

    We quantum mechanically analyze the fractional quantum Hall effect in graphene. This will be done by building the corresponding states in terms of a potential governing the interactions and discussing other issues. More precisely, we consider a system of particles in the presence of an external magnetic field and take into account of a specific interaction that captures the basic features of the Laughlin series \

  1. Induced radioisotopes in a linac treatment hall

    International Nuclear Information System (INIS)

    When linacs operate above 8 MV an undesirable neutron field is produced whose spectrum has three main components: the direct spectrum due to those neutrons leaking out from the linac head, the scattered spectrum due to neutrons produced in the head that collides with the nuclei in the head losing energy and the third spectrum due to room-return effect. The third category of spectrum has mainly epithermal and thermal neutrons being constant at any location in the treatment hall. These neutrons induce activation in the linac components, the concrete walls and in the patient body. Here the induced radioisotopes have been identified in concrete samples located in the hall and in one of the wedges. The identification has been carried out using a gamma-ray spectrometer. - Highlights: • Portland cement samples were located inside a treatment hall with a 15 MV linac. • Induced radioisotopes were measured with a NaI(Tl) γ-ray spectrometer. • 56Mn, 24Na, and 28Al were identified and the specific activity was estimated. • In a wedge, 56Mn was induced by the photoneutrons

  2. A Magnetic Balance with Hall Effect Sensors

    Science.gov (United States)

    Sawada, Hideo; Kunimasu, Tetsuya; Suda, Shinichi; Mizoguti, Yasushi; Okada, Takumi

    Magnetic force acting on a model fixed at the center of the JAXA 60cm MSBS was measured with an industry manufactured balance system when MSBS control coil currents were varied. At the same time, magnetic field intensity was also measured with 11 Hall sensors, which were arranged around the MSBS test section. From relations between coil currents and its corresponding controlled magnetic forces, regressive curves were given and maximum deviation from the curves was evaluated. From relations between Hall sensor outputs and the magnetic forces, regressive curves and deviation were also obtained. Obtained results show Hall sensor outputs are much better indexes of balance than the coil currents. The maximum deviations were reduced to a half or one-third times as much as those evaluated using the control coil currents. However, when couples acting on the model are controlled, they are not effective to reduce hysteresis phenomenon in the relation. The deviation can be reduced by decreasing the range of calibration. Then, the error of the balance of the MSBS was reduced to about 1% of the calibration range.

  3. Bronquiectasias, estudio de 36 pacientes intervenidos en el hospital “Dr. Rafael Ángel Calderón Guardia” Bronchiectasis, Results of Surgical Intervention in 36 Patients

    Directory of Open Access Journals (Sweden)

    José Alberto Mainieri-Hidalgo

    2011-09-01

    Full Text Available Objetivo: Analizar el resultado de la cirugía por bronquiectasias en el Servicio de Cirugía de Tórax del Hospital Calderón Guardia. Método: Se revisaron los expedientes clínicos de 36 pacientes operados, con un total de 44 intervenciones por bronquiectasias. Resultados: Se encontró una prevalencia muy significativa de la enfermedad en mujeres, con una relación de 11 a 1. La etiología fue en 10 casos el antecedente de tuberculosis, en uno el síndrome de Kartagener, y en 25 no se logró establecer. Todos los pacientes tenían antecedente de tos y expectoración mucopurulenta de larga evolución, y 29 habían sido clasificados como asmáticos, aunque 10 no tenían ningún antecedente familiar. La radiografía de tórax fue anormal en todos los casos, mostrando áreas de fibrosis, infiltrados o nódulos, pero no fue útil para establecer el diagnóstico de bronquiectasias, contrario a la TAC, que en todos mostró las lesiones bronquiales. El resultado de la cirugía, contrario a lo esperado, no logró establecer un indicador de éxito, pues pacientes con lesiones muy localizadas continuaron expectorando e infectándose, y otros con patología difusa y bilateral, mejoraron sustancialmente. Conclusiones: La cirugía por bronquiectasias está indicada cuando el tratamiento médico no logra controlar satisfactoriamente los cuadros infecciosos bronquiales. Existe franca posibilidad de mejoría, pero no un indicador de éxito para el procedimiento quirúrgico.Aim: To analyze the results of surgical interventions due to bronchiectasias at the Thoracic Surgery Department of the Dr. R. A. Calderón Guardia Hospital. Methods: In order to review the results of 44 surgical interventions due to bronchiectasias at the Thoracic Surgery Department of Calderón Guardia Hospital, the clinical files of 36 patients were examined. Results: A significant prevalence of the disease in female patients was observed, in proportion of 11 to 1. In most cases, causal

  4. Resonant soft x-ray reflectivity of Me/B(4)C multilayers near the boron K edge.

    Science.gov (United States)

    Ksenzov, Dmitriy; Schlemper, Christoph; Pietsch, Ullrich

    2010-09-01

    Energy dependence of the optical constants of boron carbide in the short period Ru/B(4)C and Mo/B(4)C multilayers (MLs) are evaluated from complete reflectivity scans across the boron K edge using the energy-resolved photon-in-photon-out method. Differences between the refractive indices of the B(4)Cmaterial inside and close to the surface are obtained from the peak profile of the first order ML Bragg peak and the reflection profile near the critical angle of total external reflection close to the surface. Where a Mo/B(4)C ML with narrow barrier layers appears as a homogeneous ML at all energies, a Ru/B(4)C ML exhibits another chemical nature of boron at the surface compared to the bulk. From evaluation of the critical angle of total external reflection in the energy range between 184 and 186eV, we found an enriched concentration of metallic boron inside the Ru-rich layer at the surface, which is not visible in other energy ranges.

  5. Fabrication and superconducting properties of internal Mg diffusion processed MgB2 wires using MgB4 precursors

    Science.gov (United States)

    Xu, Da; Wang, Dongliang; Yao, Chao; Zhang, Xianping; Ma, Yanwei; Oguro, Hidetoshi; Awaji, Satoshi; Watanabe, Kazuo

    2016-10-01

    Monofilament MgB2/Nb/Monel wires were fabricated using three different MgB4 precursors by an internal Mg diffusion (IMD) process. The wire geometry and heat-treatment conditions were optimized in order to improve the critical current density (J c) of the MgB2 wire. The influences of the quality of MgB4 powders, such as the particle size and MgO impurity, on the microstructure and superconducting properties of the wires were discussed. Although there were small amounts of voids, unreacted MgB4 particles and MgO impurity existed in the superconducting layers, and the transport layer J c of the wire with the MgB4 precursor reached 3.0 × 104 A cm-2 at 4.2 K and 10 T, which was comparable to that of IMD-processed wires fabricated using boron precursors. Both the non-barrier J c and engineering J c of MgB2 wire made using a MgB4 precursor were enhanced due to the improved grain connectivity and the enlarged fill factor.

  6. B4CN3 and B3CN4 monolayers as the promising candidates for metal-free spintronic materials

    Science.gov (United States)

    Pan, Hongzhe; Sun, Yuanyuan; Zheng, Yongping; Tang, Nujiang; Du, Youwei

    2016-09-01

    The search for candidates of spintronic materials, especially among the two-dimensional (2D) materials, has attracted tremendous attentions over the past decades. By using a particle swarm optimization structure searching method combined with density functional calculations, two kinds of boron carbonitride monolayer structures (B4CN3 and B3CN4) are proposed and confirmed to be dynamically and kinetically stable. Intriguingly, we demonstrate that the magnetic ground states of the two B x C y N z systems are ferromagnetic ordering with a high Curie temperature of respectively 337 K for B4CN3 and 309 K for B3CN4. Furthermore, based on their respective band structures, the B4CN3 is found to be a bipolar magnetic semiconductor (BMS), while the B3CN4 is identified to be a type of spin gapless semiconductor (SGS), both of which are potential spintronic materials. In particular, carrier doping in the B4CN3 can induce a transition from BMS to half-metal, and its spin polarization direction is switchable depending on the doped carrier type. The BMS property of B4CN3 is very robust under an external strain or even a strong electric field. By contrast, as a SGS, the electronic structure of B3CN4 is relatively sensitive to external influences. Our findings successfully disclose two promising materials toward 2D metal-free spintronic applications.

  7. Dissipationless spin-Hall current contribution in the extrinsic spin-Hall effect

    Institute of Scientific and Technical Information of China (English)

    Yan Yu-Zhen; Li Hui-Wu; Hu Liang-Bin

    2009-01-01

    This paper shows that a substantial amount of dissipationless spin-Hall current contribution may exist in the extrinsic spin-Hall effect, which originates from the spin-orbit coupling induced by the applied external electric field itself that drives the extrinsic spin-Hall effect in a nonmagnetic semiconductor (or metal). By assuming that the impurity density is in a moderate range such that the total scattering potential due to all randomly distributed impurities is a smooth function of the space coordinate, it is shown that this dissipationless contribution shall be of the same orders of magnitude as the usual extrinsic contribution from spin-orbit dependent impurity scatterings (or may even be larger than the latter one). The theoretical results obtained are in good agreement with recent relevant experimental results.

  8. Hall viscosity: A link between quantum Hall systems, plasmas and liquid crystals

    International Nuclear Information System (INIS)

    In this Letter, the assumption of two simple postulates is shown to give rise to a Hall viscosity term via an action principle formulation. The rationale behind the two postulates is clearly delineated, and the connections to an intrinsic angular momentum are emphasized. By employing this methodology, it is shown that Hall viscosity appears in a wide range of fields, and the interconnectedness of quantum Hall systems, plasmas and nematic liquid crystals is hypothesized. Potential avenues for experimental and theoretical work arising from this cross-fertilization are also indicated. - Highlights: • Connections between simple 2D fluid models in different fields of physics presented. • Structure emerges via varied physical mechanisms driven by internal angular momentum. • Properties of these models such as Casimirs, equilibria and stability are analyzed

  9. Research on Factors Affecting Drawing Property of B4L1 Wire Rod%影响B4L1盘条拉拔性能的因素研究

    Institute of Scientific and Technical Information of China (English)

    肖九红

    2004-01-01

    运用回归分析法,研究化学成分对B4L1盘条拉拔性能的影响.生产实践表明:通过调整轧制控冷工艺和改进拉拔工艺可提高B4L1盘条拉拔性能,当钢中Als(酸溶铝)的质量分数在0.012%以上时,盘条拉拔性能明显提高.

  10. Conductivity tensor in a holographic quantum Hall ferromagnet

    International Nuclear Information System (INIS)

    The Hall and longitudinal conductivities of a recently studied holographic model of a quantum Hall ferromagnet are computed using the Karch–O'Bannon technique. In addition, the low temperature entropy of the model is determined. The holographic model has a phase transition as the Landau level filling fraction is increased from zero to one. We argue that this phase transition allows the longitudinal conductivity to have features qualitatively similar to those of two dimensional electron gases in the integer quantum Hall regime. The argument also applies to the low temperature limit of the entropy. The Hall conductivity is found to have an interesting structure. Even though it does not exhibit Hall plateaux, it has a flattened dependence on the filling fraction with a jump, analogous to the interpolation between Hall plateaux, at the phase transition

  11. Commemorative Symposium on the Hall Effect and its Applications

    CERN Document Server

    Westgate, C

    1980-01-01

    In 1879, while a graduate student under Henry Rowland at the Physics Department of The Johns Hopkins University, Edwin Herbert Hall discovered what is now universally known as the Hall effect. A symposium was held at The Johns Hopkins University on November 13, 1979 to commemorate the lOOth anniversary of the discovery. Over 170 participants attended the symposium which included eleven in­ vited lectures and three speeches during the luncheon. During the past one hundred years, we have witnessed ever ex­ panding activities in the field of the Hall effect. The Hall effect is now an indispensable tool in the studies of many branches of condensed matter physics, especially in metals, semiconductors, and magnetic solids. Various components (over 200 million!) that utilize the Hall effect have been successfully incorporated into such devices as keyboards, automobile ignitions, gaussmeters, and satellites. This volume attempts to capture the important aspects of the Hall effect and its applications. It includes t...

  12. Conductivity Tensor in a Holographic Quantum Hall Ferromagnet

    CERN Document Server

    Hutchinson, J; Semenoff, G W

    2014-01-01

    The Hall and longitudinal conductivities of a recently studied holographic model of a quantum Hall ferromagnet are computed using the Karch-O'Bannon technique. In addition, the low temperature entropy of the model is determined. The holographic model has a phase transition as the Landau level filling fraction is increased from zero to one. We argue that this phase transition allows the longitudinal conductivity to have features qualitatively similar to those of two dimensional electron gases in the integer quantum Hall regime. The argument also applies to the low temperature limit of the entropy. The Hall conductivity is found to have an interesting structure. Even though it does not exhibit Hall plateaux, it has a flattened dependence on the filling fraction with a jump, analogous to the interpolation between Hall plateaux, at the phase transition.

  13. Conductivity tensor in a holographic quantum Hall ferromagnet

    Directory of Open Access Journals (Sweden)

    Joel Hutchinson

    2014-11-01

    Full Text Available The Hall and longitudinal conductivities of a recently studied holographic model of a quantum Hall ferromagnet are computed using the Karch–O'Bannon technique. In addition, the low temperature entropy of the model is determined. The holographic model has a phase transition as the Landau level filling fraction is increased from zero to one. We argue that this phase transition allows the longitudinal conductivity to have features qualitatively similar to those of two dimensional electron gases in the integer quantum Hall regime. The argument also applies to the low temperature limit of the entropy. The Hall conductivity is found to have an interesting structure. Even though it does not exhibit Hall plateaux, it has a flattened dependence on the filling fraction with a jump, analogous to the interpolation between Hall plateaux, at the phase transition.

  14. Roles of isolectin B4-binding afferents in colorectal mechanical nociception.

    Science.gov (United States)

    La, Jun-Ho; Feng, Bin; Kaji, Kaori; Schwartz, Erica S; Gebhart, G F

    2016-02-01

    Isolectin B4-binding (IB4+) dorsal root ganglion (DRG) neurons are distinct from peptidergic DRG neurons in their terminal location in the spinal cord and respective contributions to various classes and modalities of nociception. In DRG neurons innervating the mouse colon (c-DRG neurons), the reported proportion of IB4+ population is inconsistent across studies, and little is known regarding their role in colorectal mechanonociception. To address these issues, in C57BL/6J mice, we quantified IB4+ binding after labeling c-DRG neurons with Fast Blue and examined functional consequences of ablating these neurons by IB4-conjugated saporin. Sixty-one percent of Fast Blue-labeled neurons in the L6 DRG were IB4+, and 95% of these IB4+ c-DRG neurons were peptidergic. Intrathecal administration of IB4-conjugated saporin reduced the proportion of IB4+ c-DRG neurons to 37%, which was due to the loss of c-DRG neurons showing strong to medium IB4+ intensity; c-DRG neurons with weak IB4+ intensity were spared. However, this loss altered neither nociceptive behaviors to colorectal distension nor the relative proportions of stretch-sensitive colorectal afferent classes characterized by single-fiber recordings. These findings demonstrate that more than 1 half of viscerosensory L6 c-DRG neurons in C57BL/6J mouse are IB4+ and suggest, in contrast to the reported roles of IB4+/nonpeptidergic neurons in cutaneous mechanonociception, c-DRG neurons with strong-to-medium IB4+ intensity do not play a significant role in colorectal mechanonociception. PMID:26447707

  15. Metabolism of leukotriene B4 to dihydro and dihydro-oxo products by porcine leukocytes

    Energy Technology Data Exchange (ETDEWEB)

    Powell, W.S.; Gravelle, F.

    1989-04-05

    Porcine leukocytes contain a novel pathway for the metabolism of leukotriene B4 (LTB4) which results in reduction of the conjugated triene chromophore to a conjugated diene. These cells converted LTB4 to two major metabolites, both of which exhibited maximal absorbance at 230 nm in their UV spectra. These products were purified by high pressure liquid chromatography and identified as 10, 11-dihydro-LTB4 and 10,11-dihydro-12-oxo-LTB4 on the basis of the mass spectra of various derivatives. The position of the double bond of LTB4 which had been reduced was established by cleaving the remaining double bonds of 10, 11-dihydro-LTB4 with ozone followed by oxidation or reduction of the resulting ozonide and analysis of the products by mass spectrometry. Experiments with deuterium-labeled substrate indicated that LTB4 could be directly converted to 10, 11-dihydro-LTB4 without the prior oxidation of either of its hydroxyl groups, as is required for the formation of dihydro metabolites of prostaglandins. Incubation of porcine leukocytes with 10, 11-dihydro-LTB4 and 10, 11-dihydro-12-oxo-LTB4 indicated that these two products can be interconverted and are in equilibrium with one another. The dihydro-oxo metabolite can therefore be formed from 10, 11-dihydro-LTB4, although we have not ruled out the possibility that it is also produced via 12-oxo-LTB4, which could be a transitory intermediate. These results indicate that porcine leukocytes contain a novel reductase/dehydrogenase pathway distinct from the pathway responsible for the metabolism of prostaglandins. This pathway is also different from the pathway in human polymorphonuclear leukocytes which converts 6-trans-isomers of LTB4 to dihydro products, since the latter pathway involves 5-oxo intermediates and results in a shift in the positions of the remaining double bonds.

  16. Metabolism of leukotriene B4 to dihydro and dihydro-oxo products by porcine leukocytes

    International Nuclear Information System (INIS)

    Porcine leukocytes contain a novel pathway for the metabolism of leukotriene B4 (LTB4) which results in reduction of the conjugated triene chromophore to a conjugated diene. These cells converted LTB4 to two major metabolites, both of which exhibited maximal absorbance at 230 nm in their UV spectra. These products were purified by high pressure liquid chromatography and identified as 10, 11-dihydro-LTB4 and 10,11-dihydro-12-oxo-LTB4 on the basis of the mass spectra of various derivatives. The position of the double bond of LTB4 which had been reduced was established by cleaving the remaining double bonds of 10, 11-dihydro-LTB4 with ozone followed by oxidation or reduction of the resulting ozonide and analysis of the products by mass spectrometry. Experiments with deuterium-labeled substrate indicated that LTB4 could be directly converted to 10, 11-dihydro-LTB4 without the prior oxidation of either of its hydroxyl groups, as is required for the formation of dihydro metabolites of prostaglandins. Incubation of porcine leukocytes with 10, 11-dihydro-LTB4 and 10, 11-dihydro-12-oxo-LTB4 indicated that these two products can be interconverted and are in equilibrium with one another. The dihydro-oxo metabolite can therefore be formed from 10, 11-dihydro-LTB4, although we have not ruled out the possibility that it is also produced via 12-oxo-LTB4, which could be a transitory intermediate. These results indicate that porcine leukocytes contain a novel reductase/dehydrogenase pathway distinct from the pathway responsible for the metabolism of prostaglandins. This pathway is also different from the pathway in human polymorphonuclear leukocytes which converts 6-trans-isomers of LTB4 to dihydro products, since the latter pathway involves 5-oxo intermediates and results in a shift in the positions of the remaining double bonds

  17. Leukotriene B4 Enhances NOD2-Dependent Innate Response against Influenza Virus Infection.

    Directory of Open Access Journals (Sweden)

    Manon Le Bel

    Full Text Available Leukotriene B4 (LTB4, a central mediator of inflammation, is well known for its chemoattractant properties on effectors cells of the immune system. LTB4 also has the ability to control microbial infection by improving host innate defenses through the release of antimicrobial peptides and modulation of intracellular Toll-like receptors (TLRs expression in response to agonist challenge. In this report, we provide evidences that LTB4 acts on nucleotide-binging oligomerization domain 2 (NOD2 pathway to enhance immune response against influenza A infection. Infected mice receiving LTB4 show improved survival, lung architecture and reduced lung viral loads as compared to placebo-treated animals. NOD2 and its downstream adaptor protein IPS-1 have been found to be essential for LTB4-mediated effects against IAV infection, as absence of NOD2 or IPS-1 diminished its capacity to control viral infection. Treatment of IAV-infected mice with LTB4 induces an increased activation of IPS-1-IRF3 axis leading to an enhanced production of IFNβ in lungs of infected mice. LTB4 also has the ability to act on the RICK-NF-κB axis since administration of LTB4 to mice challenged with MDP markedly increases the secretion of IL-6 and TNFα in lungs of mice. TAK1 appears to be essential to the action of LTB4 on NOD2 pathway since pretreatment of MEFs with TAK1 inhibitor prior stimulation with IAV or MDP strongly abrogated the potentiating effects of LTB4 on both IFNβ and cytokine secretion. Together, our results demonstrate that LTB4, through its ability to activate TAK1, potentiates both IPS-1 and RICK axis of the NOD2 pathway to improve host innate responses.

  18. New coxsackievirus B4 genotype circulating in Inner Mongolia Autonomous Region, China.

    Directory of Open Access Journals (Sweden)

    Xiaoling Tian

    Full Text Available Hand, foot, and mouth disease (HFMD surveillance was initiated in the Inner Mongolia Autonomous Region of China in 2007, a crucial scrutiny for monitoring the prevalence of enterovirus serotypes associated with HFMD patients. However, this surveillance mostly focused on enterovirus 71 (EV-A71 and coxsackievirus A16; therefore, information on other enterovirus serotypes is limited. To identify the other circulating enterovirus serotypes in the HFMD outbreaks in Inner Mongolia in 2010, clinical samples from HFMD patients were investigated. Six coxsackievirus B4 (CVB4 strains were isolated and phylogenetic analyses of VP1 sequences were performed. Full-length genome sequences of two representative CVB4 isolates were acquired and similarity plot and bootscanning analyses were performed. The phylogenetic dendrogram indicated that all CVB4 strains could be divided into 5 genotypes (Genotypes I-V with high bootstrap support (90-100%. The CVB4 prototype strain (JVB was the sole member of genotype I. CVB4 strains belonging to genotype II, which were once common in Europe and the Americas, seemingly disappeared and gave way to genotype III and IV strains, which appear to be the dominant circulating strains in the world. All Chinese CVB4 strains belonged to Genotype V, a newly identified genotype supported by a high bootstrap value (100%, and are circulating only in mainland of China. Intertypic recombination occurred in the Chinese CVB4 strains with novel unknown serotype EV-B donor sequences. Two Chinese CVB4 strains had a virulent residue at position 129 of VP1, and one strain also had a virulent residue at position 16 of VP4. Increased surveillance is needed to monitor the emergence of new genetic lineages of enteroviruses in areas that are often associated with large-scale outbreaks. In addition, continued monitoring of enteroviruses by clinical surveillance and genetic characterization should be enhanced.

  19. Leukotriene B4 enhances innate immune defense against the puerperal sepsis agent Streptococcus pyogenes.

    Science.gov (United States)

    Soares, Elyara M; Mason, Katie L; Rogers, Lisa M; Serezani, Carlos H; Faccioli, Lucia H; Aronoff, David M

    2013-02-15

    Puerperal sepsis is a leading cause of maternal mortality worldwide. Streptococcus pyogenes [group A Streptococcus; (GAS)] is a major etiologic agent of severe postpartum sepsis, yet little is known regarding the pathogenesis of these infections. Tissue macrophages provide innate defense against GAS, and their actions are highly regulated. The intracellular second messenger cAMP can negatively regulate macrophage actions against GAS. Because leukotriene (LT) B(4) has been shown to suppress intracellular cAMP in macrophages, we hypothesized that it could enhance innate defenses against GAS. We assessed the capacity of LTB(4) to modulate antistreptococcal actions of human macrophages, including placental and decidual macrophages and used a novel intrauterine infection model of GAS in mice lacking the 5-lipoxygenase enzyme to determine the role of endogenous LTs in host defense against this pathogen. Animals lacking 5-lipoxygenase were significantly more vulnerable to intrauterine GAS infection than were wild-type mice and showed enhanced dissemination of bacteria out of the uterus and a more robust inflammatory response than did wild-type mice. In addition, LTB(4) reduced intracellular cAMP levels via the BLT1 receptor and was a potent stimulant of macrophage phagocytosis and NADPH oxidase-dependent intracellular killing of GAS. Importantly, interference was observed between the macrophage immunomodulatory actions of LTB(4) and the cAMP-inducing lipid PGE(2), suggesting that interplay between pro- and anti-inflammatory compounds may be important in vivo. This work underscores the potential for pharmacological targeting of lipid mediator signaling cascades in the treatment of invasive GAS infections. PMID:23325886

  20. Degradation in steam of 60 cm-long B4C control rods

    Science.gov (United States)

    Dominguez, C.; Drouan, D.

    2014-08-01

    In the framework of nuclear reactor core meltdown accident studies, the degradation of boron carbide control rod segments exposed to argon/steam atmospheres was investigated up to about 2000 °C in IRSN laboratories. The sequence of the phenomena involved in the degradation has been found to take place as expected. Nevertheless, the ZrO2 oxide layer formed on the outer surface of the guide tube was very protective, significantly delaying and limiting the guide tube failure and therefore the boron carbide pellet oxidation. Contrary to what was expected, the presence of the control rod decreases the hydrogen release instead of increasing it by additional oxidation of boron compounds. Boron contents up to 20 wt.% were measured in metallic mixtures formed during degradation. It was observed that these metallic melts are able to attack the surrounding fuel rods, which could have consequences on fuel degradation and fission product release kinetics during severe accidents.

  1. Fabrication and Properties of SiB6-B4C with Phenolic Resin as a Carbon Source

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Si-B-C ceramic composites were synthesized using SiB6, B4C, and phenolic resin as a carbon source by pressureless sintering in an Ar atmosphere. Then, the Si-B-C ceramic composites were fabricated to determine their potential for applications as high hardness and high temperature composites. The X-ray diffraction patterns of sintered bodies of SiB6-B4C with carbonized phenolic resin can be seen that SiB6 and C changed to B4C and SiC. In this study, it is obtained that carbonized phenolic resin is good addition material as a reaction material comparing to carbon powder at 1683 K for 1 h by pressureless sintering in an Ar atmosphere.

  2. Structure and characteristics of electrodeposited RE-Ni-W-P-B4C-PTFE composite coatings

    Institute of Scientific and Technical Information of China (English)

    陈凌; 郭忠诚; 杨显万

    2001-01-01

    Hardness, friction and wear characteristics of electrodeposited RE-Ni-W-P-B4C-PTFE composite coatings were studied, and the reason for these fine characteristics was explained in respect of structure. The results show that 1)the structure of RE-Ni-W-P-B4C-PTFE composite coatings experiences a transformation process from amorphous to mixture then to crystal as the heat-treatment temperature rises; 2) incorporating of B4C greatly increases the hardness of the coating; 3) the wear resistance of the coating is best with heat-treatment for 1 h at 300 ℃, which is greatly superior to that of the other traditional coatings.

  3. Introduction to the Physics of the Quantum Hall Regime

    OpenAIRE

    MacDonald, A. H.

    1994-01-01

    These lecture notes attempt to explain the main ideas of the theory of the quantum Hall effect. The emphasis is on the localization and interaction physics in the extreme quantum limit which gives rise to the quantum Hall effect. The interaction physics in the extreme quantum limit which is responsible for the fractional quantum Hall effect is discussed at length and from an elementary point of view.

  4. A 3-D Hall Sensor for Precise Angular Position Measurements

    OpenAIRE

    DIMITROV, Konstantin Veselinov

    2007-01-01

    A 3-D silicon Hall effect sensor for precise angular-position measurement over 360° rotation is presented. This vector microtransducer functionally integrates into a common sensor region two parallel-field Hall devices for in-plane components of the magnetic field and one orthogonal Hall version for the perpendicular for the chip magnetic field. The advantages of this magnetometer are its low channel cross-sensitivities, remarkable simplified device design and high spatial resolution.

  5. Hybrid Spin Noise Spectroscopy and the Spin Hall Effect

    OpenAIRE

    Slipko, V. A.; Sinitsyn, N. A.; Pershin, Y. V.

    2013-01-01

    Here we suggest a novel hybrid spin noise spectroscopy technique, which is sensitive to the spin Hall effect. It is shown that, while the standard spin-spin correlation function is not sensitive to the spin Hall effect, spin-transverse voltage and transverse voltage-voltage correlation functions provide the missing sensitivity being linear and quadratic in the spin Hall coefficient, respectively. The correlation between transverse voltage and spin fluctuations appears as a result of spin-char...

  6. Method for electric field and potential calculations in Hall plates

    OpenAIRE

    Raman, Johan; Rombouts, Pieter; Weyten, Ludo

    2013-01-01

    Electrostatic field problems occurring in Hall plates are difficult to solve, mainly because of a non-standard boundary condition defining an oblique angle of the electric field w.r.t. an isolating boundary. A new approach for solving Hall-related field problems is presented. Compared to prior approaches, the technique leads more easily to closed-form expressions for the electric field, and allows obtaining voltage-related Hall characteristics in numerically well conditioned forms.

  7. Mesoscopic Hall effect driven by chiral spin order

    OpenAIRE

    Ohe, Jun-ichiro; Ohtsuki, Tomi; Kramer, Bernhard

    2006-01-01

    A Hall effect due to spin chirality in mesoscopic systems is predicted. We consider a 4-terminal Hall system including local spins with geometry of a vortex domain wall, where strong spin chirality appears near the center of vortex. The Fermi energy of the conduction electrons is assumed to be comparable to the exchange coupling energy where the adiabatic approximation ceases to be valid. Our results show a Hall effect where a voltage drop and a spin current arise in the transverse direction....

  8. Topological insulator in junction with ferromagnets: quantum Hall effects

    OpenAIRE

    Chudnovskiy, A. L.; Kagalovsky, V.

    2014-01-01

    The ferromagnet-topological insulator-ferromagnet (FM-TI-FM) junction exhibits thermal and electrical quantum Hall effects. The generated Hall voltage and transverse temperature gradient can be controlled by the directions of magnetizations in the FM leads, which inspires the use of FM-TI-FM junctions as electrical and as heat switches in spintronic devices. Thermal and electrical Hall coefficients are calculated as functions of the magnetization directions in ferromagnets and the spin-relaxa...

  9. Finite element modeling for temperature stabilization of gated Hall sensors

    OpenAIRE

    Jouault, B.; Bouguen, L.; Contreras, S; Kerlain, A.; Mosser, Vincent

    2008-01-01

    International audience Using finite element analysis, we have calculated the Hall voltage of gated Hall sensors in the temperature range (−55 °C, 125 °C). We investigated how both the sensor shape and the external connections influence the Hall voltage and its thermal drift. The numerical results are in excellent agreement with the experimental measurements. By contrast, we checked that simplified analytical methods lead to a large numerical error, which is not acceptable in these sensors ...

  10. Faster Hall-Effect Current-Measuring Circuit

    Science.gov (United States)

    Sullender, Craig C.; Johnson, Daniel D.; Walker, Daniel D.

    1993-01-01

    Current-measuring circuit operates on Hall-effect-sensing and magnetic-field-nulling principles similar to those described in article, "Nulling Hall-Effect Current-Measuring Circuit" (LEW-15023), but simpler and responds faster. Designed without feedback loop, and analog pulse-width-modulated output indicates measured current. Circuit measures current at frequency higher than bandwidth of its Hall-effect sensor.

  11. Basic Instrumentation for Hall A at Jefferson Jab

    Energy Technology Data Exchange (ETDEWEB)

    The Jefferson Lab Hall A Collaboration

    2003-07-01

    The instrumentation in Hall A at the JLab was designed to study electro- and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. A collaboration of approximately 50 institutions from all over the world has actively contributed and participated in the design, construction and commissioning of the Hall A instrumentation. The basic Hall A equipment is described herein.

  12. Fabrication of a vector Hall sensor for magnetic microscopy

    Science.gov (United States)

    Gregušová, D.; Cambel, V.; Fedor, J.; Kúdela, R.; Šoltýs, J.; Lalinský, T.; Kostič, I.; Bending, S. J.

    2003-05-01

    We have developed a micromachined Hall sensor for scanning the entire magnetic field vector whose active dimensions are an order of magnitude smaller (˜5 μm) than the smallest existing vector field sensor. It is realized by patterning three Hall probes on the tilted faces of epitaxy-overgrown GaAs-based pyramidal-shaped mesa structures. Data from these "tilted" Hall probes are used to reconstruct the full magnetic field vector.

  13. Thermal Hall Effect of Spins in a Paramagnet

    OpenAIRE

    Lee, Hyunyong; Han, Jung Hoon; Lee, Patrick A.

    2014-01-01

    Theory of Hall transport of spins in a correlated paramagnetic phase is developed. By identifying the thermal Hall current operator in the spin language, which turns out to equal the spin chirality in the pure Heisenberg model, various response functions can be derived straightforwardly. Subsequent reduction to the Schwinger boson representation of spins allows a convenient calculation of thermal and spin Hall coefficients in the paramagnetic regime using self-consistent mean-field theory. Co...

  14. Estimates of Quantities in a Hall Effect Geodynamo Theory

    Directory of Open Access Journals (Sweden)

    Annraoi M de Paor

    2008-01-01

    Full Text Available Currents, resistances, dynamo constant, Hall voltage coefficient and inductances are estimated for the author’s geodynamo theory incorporating the Hall Effect. It is concluded that the Hall Coefficient in the bulk liquid core of the Earth is approximately 1.512x10-1, orders of magnitude greater than in normal liquid metals. The ordering effect of enormous pressure is a possible cause.

  15. Estimates of Quantities in a Hall Effect Geodynamo Theory

    OpenAIRE

    Annraoi M de Paor

    2008-01-01

    Currents, resistances, dynamo constant, Hall voltage coefficient and inductances are estimated for the author’s geodynamo theory incorporating the Hall Effect. It is concluded that the Hall Coefficient in the bulk liquid core of the Earth is approximately 1.512x10-1, orders of magnitude greater than in normal liquid metals. The ordering effect of enormous pressure is a possible cause.

  16. 7 CFR Exhibit B-4 to Subpart B of... - Letter for Notifying Applicants, Lenders and Holders and Borrowers of Unfavorable Decision...

    Science.gov (United States)

    2010-01-01

    ... Used in Cases Involving Farmer Program Primary Loan Servicing Actions) B Exhibit B-4 to Subpart B of... AGRICULTURE PROGRAM REGULATIONS GENERAL Adverse Decisions and Administrative Appeals Pt. 1900, Subpt. B, Exh. B-4 Exhibit B-4 to Subpart B of Part 1900—Letter for Notifying Applicants, Lenders and Holders...

  17. 17 CFR 249.820 - Form 19b-4(e) for the listing and trading of new derivative securities products by self...

    Science.gov (United States)

    2010-04-01

    ... self-regulatory organization's listing and trading of a new derivative securities product that is not deemed a proposed rule change, pursuant to Rule 19b-4(e) under the Act (17 CFR 240.19b-4(e)). Editorial Note: For Federal Register citations affecting Form 19b-4(e), see the List of CFR Sections...

  18. Heterogeneous Recycling in Fast Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Forget, Benoit; Pope, Michael; Piet, Steven J.; Driscoll, Michael

    2012-07-30

    Current sodium fast reactor (SFR) designs have avoided the use of depleted uranium blankets over concerns of creating weapons grade plutonium. While reducing proliferation risks, this restrains the reactor design space considerably. This project will analyze various blanket and transmutation target configurations that could broaden the design space while still addressing the non-proliferation issues. The blanket designs will be assessed based on the transmutation efficiency of key minor actinide (MA) isotopes and also on mitigation of associated proliferation risks. This study will also evaluate SFR core performance under different scenarios in which depleted uranium blankets are modified to include minor actinides with or without moderators (e.g. BeO, MgO, B4C, and hydrides). This will be done in an effort to increase the sustainability of the reactor and increase its power density while still offering a proliferation resistant design with the capability of burning MA waste produced from light water reactors (LWRs). Researchers will also analyze the use of recycled (as opposed to depleted) uranium in the blankets. The various designs will compare MA transmutation efficiency, plutonium breeding characteristics, proliferation risk, shutdown margins and reactivity coefficients with a current reference sodium fast reactor design employing homogeneous recycling. The team will also evaluate the out-of-core accumulation and/or burn-down rates of MAs and plutonium isotopes on a cycle-by-cycle basis. This cycle-by-cycle information will be produced in a format readily usable by the fuel cycle systems analysis code, VISION, for assessment of the sustainability of the deployment scenarios.

  19. The Radon Monitoring System in Daya Bay Reactor Neutrino Experiment

    CERN Document Server

    Chu, M C; Kwok, M W; Kwok, T; Leung, J K C; Leung, K Y; Lin, Y C; Luk, K B; Pun, C S J

    2016-01-01

    We developed a highly sensitive, reliable and portable automatic system (H$^{3}$) to monitor the radon concentration of the underground experimental halls of the Daya Bay Reactor Neutrino Experiment. H$^{3}$ is able to measure radon concentration with a statistical error less than 10\\% in a 1-hour measurement of dehumidified air (R.H. 5\\% at 25$^{\\circ}$C) with radon concentration as low as 50 Bq/m$^{3}$. This is achieved by using a large radon progeny collection chamber, semiconductor $\\alpha$-particle detector with high energy resolution, improved electronics and software. The integrated radon monitoring system is highly customizable to operate in different run modes at scheduled times and can be controlled remotely to sample radon in ambient air or in water from the water pools where the antineutrino detectors are being housed. The radon monitoring system has been running in the three experimental halls of the Daya Bay Reactor Neutrino Experiment since November 2013.

  20. Dynamic Feedback in Ferromagnet-Spin Hall Metal Heterostructures.

    Science.gov (United States)

    Cheng, Ran; Zhu, Jian-Gang; Xiao, Di

    2016-08-26

    In ferromagnet-normal-metal heterostructures, spin pumping and spin-transfer torques are two reciprocal processes that occur concomitantly. Their interplay introduces a dynamic feedback effect interconnecting energy dissipation channels of both magnetization and current. By solving the spin diffusion process in the presence of the spin Hall effect in the normal metal, we show that the dynamic feedback gives rise to (i) a nonlinear magnetic damping that is crucial to sustain uniform steady-state oscillations of a spin Hall oscillator at large angles and (ii) a frequency-dependent spin Hall magnetoimpedance that reduces to the spin Hall magnetoresistance in the dc limit. PMID:27610880

  1. Quantized Anomalous Hall Effect in Magnetic Topological Insulators

    Institute of Scientific and Technical Information of China (English)

    YU Rui

    2011-01-01

    @@ The Hall effect, the anomalous Hall effect (AHE) and the spin Hall effect are fundamental transport processes in solids arising from the Lorentz force and the spin-orbit coupling respectively.The AHE, in which a voltage transverse to the electric current appears even in the absence of an external magnetic field, was first detected in ferromagnetic (FM) metals in 1881 and later found to arise from the spin-orbit coupling (SOC) between the current and magnetic moments.Recent progress on the mechanism of AHE has established a link between the AHE and the topological nature of the Hall current by adopting the Berry-phase concepts in close analogy to the intrinsic spin Hall effect.Given the experimental discovery of the quantum Hall and the quantum spin Hall effects, it is natural to ask whether the AHE can also be quantized.In a quantized anomalous Hall (QAH) insulator, spontaneous magnetic moments and spin-orbit coupling combine to give rise to a topologically non-trivial electronic structure, leading to the quantized Hall effect without any external magnetic field.

  2. Dynamic Feedback in Ferromagnet-Spin Hall Metal Heterostructures

    Science.gov (United States)

    Cheng, Ran; Zhu, Jian-Gang; Xiao, Di

    2016-08-01

    In ferromagnet-normal-metal heterostructures, spin pumping and spin-transfer torques are two reciprocal processes that occur concomitantly. Their interplay introduces a dynamic feedback effect interconnecting energy dissipation channels of both magnetization and current. By solving the spin diffusion process in the presence of the spin Hall effect in the normal metal, we show that the dynamic feedback gives rise to (i) a nonlinear magnetic damping that is crucial to sustain uniform steady-state oscillations of a spin Hall oscillator at large angles and (ii) a frequency-dependent spin Hall magnetoimpedance that reduces to the spin Hall magnetoresistance in the dc limit.

  3. Quantum pumping and quantized magnetoresistance in a Hall bar

    OpenAIRE

    Blaauboer, M.

    2003-01-01

    We show how a dc current can be generated in a Hall bar without applying a bias voltage. The Hall resistance $R_H$ that corresponds to this pumped current is quantized, just as in the usual integer quantum Hall effect (IQHE). In contrast with the IQHE, however, the longitudinal resistance $R_{xx}$ does not vanish on the plateaus, but equals the Hall resistance. We propose an experimental geometry to measure the pumped current and verify the predicted behavior of $R_H$ and $R_{xx}$.

  4. Inverse Spin Hall Effect Driven by Spin Motive Force

    OpenAIRE

    Shibata, Junya; Kohno, Hiroshi

    2008-01-01

    The spin Hall effect is a phenomenon that an electric field induces a spin Hall current. In this Letter, we examine the inverse effect that, in a ferromagnetic conductor, a charge Hall current is induced by a spin motive force, or a spin-dependent effective ` electric' field ${\\bm E}_{\\rm s}$, arising from the time variation of magnetization texture. By considering skew-scattering and side-jump processes due to spin-orbit interaction at impurities, we obtain the Hall current density as $\\sigm...

  5. Probing magnetic microstructures with quasi-ballistic Hall crosses

    Science.gov (United States)

    Fasbender, S.; Schluck, J.; Cerchez, M.; Heinzel, T.; Sievers, S.; Pierz, K.; Schumacher, H. W.

    2016-03-01

    Hall sensing is performed on a localized magnetic field pattern using a quasi-ballistic Hall cross device. The Hall resistance shows a pronounced peak as a function of the magnetic field amplitude which is absent in the magnetization hysteresis loop. This non-monotonic response exemplifies qualitatively the failure of conventional Hall sensing. It is demonstrated how, by using a numerical simulation based on the Landauer-Büttiker model, the amplitude of the magnetic field profile can be determined from such measurements.

  6. Hall Sensor Output Signal Fault-Detection & Safety Implementation Logic

    Directory of Open Access Journals (Sweden)

    Lee SangHun

    2016-01-01

    Full Text Available Recently BLDC motors have been popular in various industrial applications and electric mobility. Recently BLDC motors have been popular in various industrial applications and electric mobility. In most brushless direct current (BLDC motor drives, there are three hall sensors as a position reference. Low resolution hall effect sensor is popularly used to estimate the rotor position because of its good comprehensive performance such as low cost, high reliability and sufficient precision. Various possible faults may happen in a hall effect sensor. This paper presents a fault-tolerant operation method that allows the control of a BLDC motor with one faulty hall sensor and presents the hall sensor output fault-tolerant control strategy. The situations considered are when the output from a hall sensor stays continuously at low or high levels, or a short-time pulse appears on a hall sensor signal. For fault detection, identification of a faulty signal and generating a substitute signal, this method only needs the information from the hall sensors. There are a few research work on hall effect sensor failure of BLDC motor. The conventional fault diagnosis methods are signal analysis, model based analysis and knowledge based analysis. The proposed method is signal based analysis using a compensation signal for reconfiguration and therefore fault diagnosis can be fast. The proposed method is validated to execute the simulation using PSIM.

  7. The Hall module of an exact category with duality

    OpenAIRE

    Young, Matthew B.

    2012-01-01

    We construct from a finitary exact category with duality a module over its Hall algebra, called the Hall module, encoding the first order self-dual extension structure of the category. We study in detail Hall modules arising from the representation theory of a quiver with involution. In this case we show that the Hall module is naturally a module over the specialized reduced sigma-analogue of the quantum Kac-Moody algebra attached to the quiver. For finite type quivers, we explicitly determin...

  8. High Efficiency Hall Thruster Discharge Power Converter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek leveraged previous, internally sponsored, high power, Hall thruster discharge converter development which allowed it to design, build, and test new printed...

  9. Graphene Hall bar with an asymmetric pn-junction

    OpenAIRE

    Milovanovic, S. P.; Masir, M. Ramezani; Peeters, F. M.

    2013-01-01

    We investigated the magnetic field dependence of the Hall and the bend resistances in the ballistic regime for a single layer graphene Hall bar structure containing a pn-junction. When both regions are n-type the Hall resistance dominates and Hall type of plateaus are formed. These plateaus occur as a consequence of the restriction on the angle imposed by Snell's law allowing only electrons with a certain initial angles to transmit though the potential step. The size of the plateau and its po...

  10. Composite particle and field theory in atomic quantum Hall effect

    Institute of Scientific and Technical Information of China (English)

    Zhao Bo; Chen Zeng-Bing

    2005-01-01

    In this paper, we explore the composite particle description of the atomic quantum Hall (QH) effect. We further give the Chern-Simon-Gross-Pitaevskii (CSGP) effective theory for the atomic Hall liquid, which is the counterpart of Chern-Simon theory in electron Hall effect. What we obtained is equivalent to the Laughlin wavefunction approach.Our results show that in terms of composite particles, the atomic Hall effect is really the same as the electronic QH effect. The CSGP effective theory would shed new light on the atomic QH effect.

  11. Precision of single-engage micro Hall effect measurements

    DEFF Research Database (Denmark)

    Henrichsen, Henrik Hartmann; Hansen, Ole; Kjær, Daniel;

    2014-01-01

    Recently a novel microscale Hall effect measurement technique has been developed to extract sheet resistance (RS), Hall sheet carrier density (NHS) and Hall mobility (μH) from collinear micro 4-point probe measurements in the vicinity of an insulating boundary [1]. The technique measures in less......]. In this study we calculate the measurement error on RS, NHS and μH resulting from electrode position errors, probe placement, sample size and Hall signal magnitude. We show the relationship between measurement precision and electrode pitch, which is important when down-scaling the micro 4-point probe to fit...

  12. Dissociated Presenilin-1 and TACE Processing of ErbB4 in Lung Alveolar Type II Cell Differentiation

    OpenAIRE

    Fiaturi, Najla; Ritzkat, Anika; Dammann, Christiane E. L.; Castellot, John J.; Nielsen, Heber C.

    2014-01-01

    Neuregulin (NRG) stimulation of ErbB4 signaling is important for type II cell surfactant synthesis. ErbB4 may mediate gene expression via a non-canonical pathway involving enzymatic cleavage releasing its intracellular domain (4ICD) for nuclear trafficking and gene regulation. The accepted model for release of 4ICD is consecutive cleavage by Tumor necrosis factor alpha Converting Enzyme (TACE) and γ-secretase enzymes. Here, we show that 4ICD mediates surfactant synthesis and its release by γ-...

  13. An open conformation of mammalian cytochrome P450 2B4 at 1.6-Å resolution

    OpenAIRE

    Scott, Emily E.; He, You Ai; Wester, Michael R.; White, Mark A.; Chin, Christopher C.; Halpert, James R.; Johnson, Eric F.; Stout, C. David

    2003-01-01

    The xenobiotic metabolizing cytochromes P450 (P450s) are among the most versatile biological catalysts known, but knowledge of the structural basis for their broad substrate specificity has been limited. P450 2B4 has been frequently used as an experimental model for biochemical and biophysical studies of these membrane proteins. A 1.6-Å crystal structure of P450 2B4 reveals a large open cleft that extends from the protein surface directly to the heme iron between the α-helical and β-sheet dom...

  14. Thermal Diffusivity Measurements of Li2B4O7 and KNbO3 Solution by Laser Flash Method

    Institute of Scientific and Technical Information of China (English)

    金蔚青; 长岛敏夫; 依田真一; 梁歆桉; 潘志雷

    2002-01-01

    The thermal diffusivities of Li2B4O7+KNbO3(20 wt%) solution have been determined at temperatures between 900℃ and 990℃ using a three-layered laser flash method on the differential scheme. The thermal diffusivity of this Li2B4O7 and KNbO3 solution ranges from 3.6.×10-3 cm2/s to 4.1×10-3 cm2/s. A positive temperature dependence of thermal diffusivity of solution is obtained.

  15. Diagnostics Systems for Permanent Hall Thrusters Development

    Science.gov (United States)

    Ferreira, Jose Leonardo; Soares Ferreira, Ivan; Santos, Jean; Miranda, Rodrigo; Possa, M. Gabriela

    This work describes the development of Permanent Magnet Hall Effect Plasma Thruster (PHALL) and its diagnostic systems at The Plasma Physics Laboratory of University of Brasilia. The project consists on the construction and characterization of plasma propulsion engines based on the Hall Effect. Electric thrusters have been employed in over 220 successful space missions. Two types stand out: the Hall-Effect Thruster (HET) and the Gridded Ion Engine (GIE). The first, which we deal with in this project, has the advantage of greater simplicity of operation, a smaller weight for the propulsion subsystem and a longer shelf life. It can operate in two configurations: magnetic layer and anode layer, the difference between the two lying in the positioning of the anode inside the plasma channel. A Hall-Effect Thruster-HET is a type of plasma thruster in which the propellant gas is ionized and accelerated by a magneto hydrodynamic effect combined with electrostatic ion acceleration. So the essential operating principle of the HET is that it uses a J x B force and an electrostatic potential to accelerate ions up to high speeds. In a HET, the attractive negative charge is provided by electrons at the open end of the Thruster instead of a grid, as in the case of the electrostatic ion thrusters. A strong radial magnetic field is used to hold the electrons in place, with the combination of the magnetic field and the electrostatic potential force generating a fast circulating electron current, the Hall current, around the axis of the Thruster, mainly composed by drifting electrons in an ion plasma background. Only a slow axial drift towards the anode occurs. The main attractive features of the Hall-Effect Thruster are its simple design and operating principles. Most of the Hall-Effect Thrusters use electromagnet coils to produce the main magnetic field responsible for plasma generation and acceleration. In this paper we present a different new concept, a Permanent Magnet Hall

  16. Sonochemical Reactors.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  17. Development of hydride absorber for fast reactor. Application of hafnium hydride to control rod of large fast reactor

    International Nuclear Information System (INIS)

    The application of hafnium hydride (Hf-hydride) to a control rod for a large fast reactor where the B4C control rod is originally employed is studied. Three types of Hf-hydride control rods are designed. The control rod worth and its change during the burnup are evaluated for different hydrogen-to-hafnium ratios and are compared with those of the original B4C control rod. The result indicates that the worths of the Hf-hydride and the 10B-enriched B4C control rods are approximately the same, and the lifetime of the Hf-hydride control rod is almost four times longer than that of the 10B-enriched B4C control rod. The core performances of the shutdown margin, sodium void reactivity, Doppler reactivity coefficient, and breeding ratio are analyzed. It is indicated that those for the Hf-hydride control rod are almost the same as those for the original B4C control rod. The behavior of neutrons moderated by the Hf-hydride control rod is analyzed. It is confirmed that the Hf-hydride control rod does not cause any thermal spike problems in the fast reactor core. (author)

  18. Leukotriene B4 levels in human atherosclerotic plaques and abdominal aortic aneurysms.

    Directory of Open Access Journals (Sweden)

    Pleunie van den Borne

    Full Text Available BACKGROUND: Leukotriene B4 (LTB4 has been associated with the initiation and progression of atherosclerosis and abdominal aortic aneurysm (AAA formation. However, associations of LTB4 levels with tissue characteristics and adverse clinical outcome of advanced atherosclerosis and AAA are scarcely studied. We hypothesized that LTB4 levels are associated with a vulnerable plaque phenotype and adverse clinical outcome. Furthermore, that LTB4 levels are associated with inflammatory AAA and adverse clinical outcome. METHODS: Atherosclerotic plaques and AAA specimens were selected from two independent databases for LTB4 measurements. Plaques were isolated during carotid endarterectomy from asymptomatic (n = 58 or symptomatic (n = 317 patients, classified prior to surgery. LTB4 levels were measured without prior lipid extraction and levels were corrected for protein content. LTB4 levels were related to plaque phenotype, baseline patient characteristics and clinical outcome within three years following surgery. Seven non-diseased mammary artery specimens served as controls. AAA specimens were isolated during open repair, classified as elective (n = 189, symptomatic (n = 29 or ruptured (n = 23. LTB4 levels were measured similar to the plaque measurements and were related to tissue characteristics, baseline patient characteristics and clinical outcome. Twenty-six non-diseased aortic specimens served as controls. RESULTS: LTB4 levels corrected for protein content were not significantly associated with histological characteristics specific for vulnerable plaques or inflammatory AAA as well as clinical presentation. Moreover, it could not predict secondary manifestations independently investigated in both databases. However, LTB4 levels were significantly lower in controls compared to plaque (p = 0.025 or AAA (p = 0.017. CONCLUSIONS: LTB4 levels were not associated with a vulnerable plaque phenotype or inflammatory AAA or clinical

  19. Supernova Early Warning in Daya Bay Reactor Neutrino Experiment

    OpenAIRE

    Hanyu Wei for the Daya Bay collaboration

    2013-01-01

    Providing an early warning of a galactic supernova using neutrino signals is of importance in studying both supernova dynamics and neutrino physics. The Daya Bay reactor neutrino experiment, with a unique feature of multiple liquid scintillator detectors separated in space, is sensitive to the full energy spectrum of supernova burst electron-antineutrinos. By deploying 8 Antineutrino Detectors (ADs) in three different experimental halls, we obtain a more powerful and prompt rejection of muon ...

  20. Leiomioma esofágico: Experiencia con diez casos operados en el "Hospital Dr. Rafael Ángel Calderón Guardia" Esophageal leiomyoma: Experience with nine surgical patients

    Directory of Open Access Journals (Sweden)

    Giovanna Mainieri-Breedy

    2012-09-01

    Full Text Available Objetivo: informar la experiencia adquirida con la cirugía para leiomiomas esofágicos en el Servicio de Cirugía de Tórax del Hospital Dr. R. A. Calderón Guardia. Métodos: durante el período de 12 años comprendido entre 1999 y 2011, fueron referidos 14 pacientes con tumores submucosos del esófago al Servicio de Cirugía de Tórax del Hospital Calderón Guardia. En cuatro pacientes asintomáticos con tumores pequeños se decidió observar, y diez fueron operados, confirmándose el diagnóstico histológico de leiomioma. Previa autorización del Comité de Ética del Hospital, se revisaron los expedientes clínicos, analizando las características personales, los síntomas, los métodos de diagnóstico, el tratamiento quirúrgico y la evolución de los pacientes operados. Resultados: se encontró que de los diez pacientes operados, ocho fueron varones, en edades entre los 38 y 71 años, con un promedio de 56 años. El síntoma principal fue disfagia, pero en 3 casos el tumor fue un hallazgo incidental de una endoscopia de rutina. El método de detección en todos los casos fue la endoscopia en la que se describió un tumor submucoso o una compresión extrínseca de la pared esofágica. El ultrasonido endoscópico se correlacionó con un tumor originado en la cuarta capa, posible leiomioma. En dos casos, debido a las dimensiones de la lesión, se planteó la posibilidad de malignidad. La tumoración se intervino en nueve casos por toracotomía y en uno, por laparotomía. En 7 casos se enucleó sin que se abriera la mucosa, en dos se realizó esofagectomía parcial con anastomosis y parche de diafragma, y en un caso, excepcional, la tumoración se extendía desde el esófago cervical hasta la unión esófago-gástrica, de manera que se realizó una esofagectomía total, con ascenso gástrico y anastomosis cervical. No hubo ningún caso de mortalidad. Un paciente presentó una pequeña fuga de la anastomosis, la cual resolvió espont