WorldWideScience

Sample records for band conductors chemisch

  1. Non-equilibrium and band tailing in organic conductors

    Indian Academy of Sciences (India)

    A T Oza; P C Vinodkumar; R G Patel

    2003-03-01

    The concept of band tailing with focal point and width of the tail from IR absorption spectra of different organic conductors is found valid even for thermal and elastic changes. The experimental situations like change of solvents, method of preparation, applied pressure and pressure cycle apart from compositions is analyzed within the framework of tailing of states. Non-equilibrium due to coupling between applied energy and free electrons can be responsible for the exponential relaxation from non-equilibrium to equilibrium.

  2. Single-band and Dual-band Artificial Magnetic Conductor Ground Planes for Multi-band Dipole Antenna

    Directory of Open Access Journals (Sweden)

    M. Abu

    2012-12-01

    Full Text Available Two new designs of high impedance surface (HIS structure are presented, namely zigzag and slotted rectangular with I-shaped slot Artificial Magnetic Conductor (AMC. The zigzag AMC is designed based on the straight dipole AMC. The zigzag AMC is introduced to minimize the AMC size and to be suitable for UHF RFID applications. On the other hand, the slotted rectangular with I-shaped slot AMC is designed to operate at 0.92 GHz and 2.45 GHz. The slot is loaded in the main patch of the AMC to create the other resonant frequency. By using this technique the resonant frequency can be lowered, and hence reduce the size of the AMC. Both structures are designed using the same dielectric substrate that is Taconic TLC-32. The properties of the AMC are investigated such as the reflection phase, reflection magnitude and surface impedance. The designed AMCs then are used as a back plane for the printed multi-band dipole antenna. By introducing the AMC as a ground plane (GP for the printed dipole antenna, the gain of the dipole antenna is increased.

  3. Spectral properties of quasi-one-dimensional conductors with a finite transverse band dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Losic, Z Bonacic; Zupanovic, P [Department of Physics, Faculty of Natural Sciences, Mathematics and Kinesiology, University of Split, Teslina 12, 21000 Split (Croatia); Bjelis, A [Department of Physics, Faculty of Science, University of Zagreb, POB 162, 10001 Zagreb (Croatia)], E-mail: agicz@pmfst.hr, E-mail: bjelis@phy.hr

    2008-08-13

    We determine the one-particle spectral function and the corresponding derived quantities for the conducting chain lattice with finite inter-chain hopping t{sub perpendicular} and three-dimensional long-range Coulomb electron-electron interaction. The standard G{sub 0}W{sub 0} approximation is used. It is shown that, due to the optical character of the anisotropic plasmon dispersion caused by the finite t{sub perpendicular}, a low energy quasi-particle {delta}-peak appears in the spectral function in addition to the hump present at energies of the order of the plasmon energy. Particular attention is devoted to the continuous crossover from the non-Fermi liquid regime to the Fermi liquid regime with increasing t{sub perpendicular}. It is shown that the spectral weight of the hump transfers to the quasi-particle as the optical gap in the plasmon dispersion increases together with t{sub perpendicular}, with the quasi-particle residuum Z behaving like -ln t{sub perpendicular}){sup -1} in the limit t{sub perpendicular} {yields}0. Our approach is appropriate for the wide range of energy scales given by the plasmon energy and the width of the conduction band, and is complementary to the Luttinger liquid techniques that are limited to the low energy regime close to the Fermi surface.

  4. Spectral properties of quasi-one-dimensional conductors with a finite transverse band dispersion

    International Nuclear Information System (INIS)

    We determine the one-particle spectral function and the corresponding derived quantities for the conducting chain lattice with finite inter-chain hopping tperpendicular and three-dimensional long-range Coulomb electron-electron interaction. The standard G0W0 approximation is used. It is shown that, due to the optical character of the anisotropic plasmon dispersion caused by the finite tperpendicular, a low energy quasi-particle δ-peak appears in the spectral function in addition to the hump present at energies of the order of the plasmon energy. Particular attention is devoted to the continuous crossover from the non-Fermi liquid regime to the Fermi liquid regime with increasing tperpendicular. It is shown that the spectral weight of the hump transfers to the quasi-particle as the optical gap in the plasmon dispersion increases together with tperpendicular, with the quasi-particle residuum Z behaving like -ln tperpendicular)-1 in the limit tperpendicular →0. Our approach is appropriate for the wide range of energy scales given by the plasmon energy and the width of the conduction band, and is complementary to the Luttinger liquid techniques that are limited to the low energy regime close to the Fermi surface

  5. Design and implementation of low profile antenna for dual-band applications using rotated e-shaped conductor-backed plane.

    Science.gov (United States)

    Jalali, Mahdi; Sedghi, Tohid; Shafei, Shahin

    2014-01-01

    A novel configuration of a printed monopole antenna with a very compact size for satisfying WLAN operations at the 5.2/5.8 GHz and also for X-band operations at the 10 GHz has been proposed. The antenna includes a simple square-shaped patch as the radiator, the rotated U-shaped conductor back plane element with embedded strip on it, and the partial rectangular ground surface. By using the rotated U-shaped conductor-backed plane with proper values, good impedance matching and improvement in bandwidth can be achieved, at the lower and upper bands. The impedance bandwidth for S11 antenna with good omnidirectional radiation characteristics, enough impedance bandwidth, and reasonable gains can be appropriate for various applications of the future developed technologies and handheld devices. PMID:24711732

  6. Design and Implementation of Low Profile Antenna for Dual-Band Applications Using Rotated E-Shaped Conductor-Backed Plane

    Directory of Open Access Journals (Sweden)

    Mahdi Jalali

    2014-01-01

    Full Text Available A novel configuration of a printed monopole antenna with a very compact size for satisfying WLAN operations at the 5.2/5.8 GHz and also for X-band operations at the 10 GHz has been proposed. The antenna includes a simple square-shaped patch as the radiator, the rotated U-shaped conductor back plane element with embedded strip on it, and the partial rectangular ground surface. By using the rotated U-shaped conductor-backed plane with proper values, good impedance matching and improvement in bandwidth can be achieved, at the lower and upper bands. The impedance bandwidth for S11<-10 dB is about 1.15 GHz for 5 GHz band and 5.3 GHz for X-band. The measured peak gains are about 1.9 dBi at WLAN-band and 4.2 dBi at X-band. The experimental results represent that the realized antenna with good omnidirectional radiation characteristics, enough impedance bandwidth, and reasonable gains can be appropriate for various applications of the future developed technologies and handheld devices.

  7. Bioassays en chemische metingen, is er een relatie?; multivariate analyse van chemische en biologische waarnemingen aan sedimenten van de Waddenzee en het Zeehavenkanaal

    OpenAIRE

    Brink, van den, W.; Kater, B.J.

    2000-01-01

    Dit rapport beschrijft de resultaten van de multivariatieanalyse van twee onderzoeken uitgevoerd door het Rijksinstituut voor Kust en Zee. In het Waddenonderzoek zijn sedimenten van zestien plaatsen in de Waddenzee zowel chemisch als biologisch beoordeeld met behulp van chemische metingen en een aantal laboratoriumbiotests in vitro en in vivo. De gegevensset van de Waddenzee is verzameld om na te gaan of waargenomen effecten in de biotests gerelateerd zijn aan de chemische karakteristieken, e...

  8. Sensorisch en chemisch onderzoek van dry en alcoholarm bier

    OpenAIRE

    Mazijk-Bokslag, van, D.M.; Cramwinckel, A.B.; Herstel, H.

    1990-01-01

    Op verzoek van Konsumenten Kontakt zijn veertien monsters bier onderzocht. De monsters zijn onderverdeeld in acht monsters alcoholarm of alcoholvrij bier, drie monsters dry bier en drie monsters gewone pils. De monsters zijn getest op sensorische verschillen. De monsters zijn verder chemisch onderzocht op alcoholgehalte, stamwortgehalte, percentage glucose en percentage malto-dextrine. Alle monsters voldoen aan de eisen van de Warenwet.

  9. Chemische analyse van huishoudelijk restafval. Resultaten 1994 en 1995

    OpenAIRE

    Beker D; Cornelissen AAJ; LAE

    1999-01-01

    Huishoudelijk restafval uit 1994 en 1995 werd geanalyseerd op een groot aantal (chemische) parameters, waaronder (zware) metalen. Het rapport geeft de resultaten weer van de concentraties zowel per hoofdcomponent (GFT, papier, kunststoffen etc.) als in het totaal huishoudelijk restafval; ook wordt de verdeling van de gemeten stoffen over de hoofdcomponenten weergegeven.

  10. Model construction and superconductivity analysis of organic conductors β-(BDA-TTP)2MF6 (M = P, As, Sb and Ta) based on first-principles band calculation

    Science.gov (United States)

    Aizawa, H.; Kuroki, K.; Yasuzuka, S.; Yamada, J.

    2012-11-01

    We perform a first-principles band calculation for a group of quasi-two-dimensional organic conductors β-(BDA-TTP)2MF6 (M = P, As, Sb and Ta). The ab-initio calculation shows that the density of states is correlated with the bandwidth of the singly occupied (highest) molecular orbital, while it is not necessarily correlated with the unit-cell volume. The direction of the major axis of the cross section of the Fermi surface lies in the Γ-B-direction, which differs from that obtained by the extended Hückel calculation. Then, we construct a tight-binding model which accurately reproduces the ab-initio band structure. The obtained transfer energies give a smaller dimerization than in the extended Hückel band. As to the difference in the anisotropy of the Fermi surface, the transfer energies along the inter-stacking direction are smaller than those obtained in the extended Hückel calculation. Assuming spin-fluctuation-mediated superconductivity, we apply random phase approximation to a two-band Hubbard model. This two-band Hubbard model is composed of the tight-binding model derived from the first-principles band structure and an on-site (intra-molecule) repulsive interaction taken as a variable parameter. The obtained superconducting gap changes sign four times along the Fermi surface like in a d-wave gap, and the nodal direction is different from that obtained in the extended Hückel model. Anion dependence of Tc is qualitatively consistent with the experimental observation.

  11. Ruimtelijke variaties in fysisch-chemische bodemkarakteristieken in de Nuenen-groep nabij Best

    NARCIS (Netherlands)

    Gerringa; L.; Obdam; A.

    1985-01-01

    Ten noorden van Best is een onderzoek uitgevoerd naar de ruimtelijke variatie in fysisch-chemische bodemkarakteristieken in de Nuenen-groep. Doel van dit onderzoek was een methode te ontwikkelen om een beter inzicht te krijgen in de laterale existentie van lagen, die door hun eigenschappen, een

  12. Chemically deposed layer sytems for the realization of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} band conductors; Chemisch deponierte Schichtsysteme zur Realisierung von YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}-Bandleitern

    Energy Technology Data Exchange (ETDEWEB)

    Engel, Sebastian

    2009-04-30

    The aim of this thesis was to produce new buffer-layer systems for biaxially texturated Ni5at%W substrates by means of chemical processes. As very promising materials for the buffer layers CaTiO{sub 3} and SrTiO{sub 3} were chosen. The production of the single layers pursued from the organometallic prestage by means of dip coating and subsequent head treatment. During the work first the single precursor solutions were to be developed. A main component of the theses forms the understanding of the texture development during the heat treatment of precursor layers on biaxially texturated metallic substrates. Based on this the growth of thick buffer layers is studied and by means of YBCO layers, which were deposed by beans of a pulsed laser, the functionality of the synthesized buffer layers proved. A further component of this thesis formes the influence of nanoscaling precipitations in thew YBCO on its superconducting properties. The YBCO deposition pursued via a variation of the TFA process, as substrate (001)-oriented SrTiO{sub 3} monocrystals were applied.

  13. Optimierung des chemisch-mechanischen Polierens von Siliziumwafern mittels stochastischer Modelle

    OpenAIRE

    Wiegand, Susanne

    2009-01-01

    Im Rahmen dieser Arbeit wurde der Prozess des chemisch-mechanischen Polierens (CMP) von Siliziumwafern erstmals mittels stochastischer Methoden modelliert und daraus resultierend weiter optimiert. Ziel war es, Erkenntnisse zu ausgewählten, noch nicht vollständig verstandenen Einflussfaktoren zu gewinnen. Der Schwerpunkt lag dabei auf dem Poliertuch. Anhand eines neu entwickelten Modells zur Beschreibung einer konditionierten Tuchoberfläche wurden Zusammenhänge zwischen Konditionier- bzw. Tuch...

  14. Chemical alternative to the energetic use of biodiesel; Chemische Alternativen zur energetischen Nutzung von Biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Warwel, S; Ruesch genannt Klaas, M.; Harperscheid, M. [Bundesanstalt fuer Getreide-, Kartoffel- und Fettforschung, Muenster (Germany). Inst. fuer Biochemie und Technologie der Fette - H.P. Kaufmann-Inst.

    1996-12-31

    Biodiesel is environment-friendly, but much more costly to produce than `normal` diesel fuel. Higher economic efficiency can be achieved by using biodiesel as a chemical feedstock instead. Tenside and polymers offer a wide range of applications. (orig) [Deutsch] Biodiesel ist ein umweltfreundlicher Kraftstoff, jedoch in der Herstellung deutlich teurer als Mineraloel-Dieselkraftstoff. Eine signifikant hoehere Wertschoepfung koennte errreicht werden, wenn Biodiesel nicht im Kraftstoffsektor, sondern als chemischer Rohstoff verwendet wird. Tenside und Polymere sind hierbei grossvolumige Einsatzbereiche. (orig)

  15. Photoconduction in CDW conductors

    Energy Technology Data Exchange (ETDEWEB)

    Zaitsev-Zotov, S.V., E-mail: serzz@cplire.ru [Kotel' nikov IRE RAS, Mokhovaya 11, Bld. 7, 125009 Moscow (Russian Federation); Minakova, V.E.; Nasretdinova, V.F.; Zybtsev, S.G. [Kotel' nikov IRE RAS, Mokhovaya 11, Bld. 7, 125009 Moscow (Russian Federation)

    2012-06-01

    Photoconduction study of quasi-1D conductors allows to distinguish between the single-particle and collective linear conduction, investigate the effect of screening on collective transport and obtain interesting new details of the electronic energy structure of pure and doped CDW conductors. Here we present results of photoconduction study in quasi-1D conductors o-TaS{sub 3}, K{sub 0.3}MoO{sub 3}, and NbS{sub 3}(I).

  16. Chemisch Induzierte Resistenz im Pathosystem Gerste - Echter Gerstenmehltau : Identifizierung und Charakterisierung differentiell exprimierter Gene der Gerste

    OpenAIRE

    Beßer, Katrin

    2001-01-01

    Die Applikation von Salicylsäure (SA) und den synthetischen Analoga 2,6-Dichlorisonikotinsäure (DCINA) und Benzo(1,2,3)thiadiazol-7-carbothionsäure-S-methylester (BTH) führt in anfälligen Gerstensorten zu einem systemischen Schutz vor einer Infektion mit dem Erreger des Echten Gerstenmehltaus (Blumeria graminis f.sp. hordei, Bgh). Bei dieser chemisch Induzierten Resistenz (cIR) werden effektive Papillen und eine Hypersensitive Reaktion als Abwehrmechanismen nach Kontakt mit dem Patho...

  17. Thunderclouds and Lightning Conductors

    Science.gov (United States)

    Martin, P. F.

    1973-01-01

    Discusses the historical background of the development of lightning conductors, describes the nature of thunderclouds and the lightning flash, and provides a calculation of the electric field under a thundercloud. Also discussed are point discharge currents and the attraction theory of the lightning conductor. (JR)

  18. Radiation damages on superionic conductors

    International Nuclear Information System (INIS)

    Irradiation coloration on superionic conductors of MA4X5 (M=K, Rb, NH4; A=Ag, Cu; X=Cl, I) was observed. Five absorption bands were observed at 1.4, 1.8, 2.1, 2.3 and 2.9 eV in RbAg4I5. In these crystals, stable coloration was observed at lower temperature than in alkali halides. The absorption bands due to electronic centers and hole one were classified from the results of optical breaching and electron or hole doping. Growth rate and induced spectra by irradiation changed drastically at the temperatures just above the superionic phase transition. The growth rate increased drastically also at 40 K. ESR signal of γ-irradiated RbCu4Cl3I2 showed that one of the induced defects is a hole trapped by a monovalent copper ion (Cu2+). (author)

  19. Organic Conductors: Evidence for Correlation Effects in Infrared Properties

    DEFF Research Database (Denmark)

    Jacobsen, Claus Schelde; Johannsen, Ib; Bechgaard, Klaus

    1984-01-01

    The infrared conductivities of four organic conductors with partially filled one-electron bands are compared. The behavior ranges from near Drude type in the best metal to semiconductorlike in the moderate conductor. Electron-molecular-vibration coupling effects of varying degree are seen in all ...... materials. It is suggested that the combined effect of electron-electron interaction and electron-phonon interaction in producing 4kF charge-density waves is essential for interpreting the results....

  20. Focus on Organic Conductors

    Directory of Open Access Journals (Sweden)

    Shinya Uji, Takehiko Mori and Toshihiro Takahashi

    2009-01-01

    Full Text Available Organic materials are usually thought of as electrical insulators. Progress in chemical synthesis, however, has brought us a rich variety of conducting organic materials, which can be classified into conducting polymers and molecular crystals. Researchers can realize highly conducting molecular crystals in charge-transfer complexes, where suitable combinations of organic electron donor or acceptor molecules with counter ions or other organic molecules provide charge carriers. By means of a kind of chemical doping, the charge-transfer complexes exhibit high electrical conductivity and, thanks to their highly crystalline nature, even superconductivity has been observed. This focus issue of Science and Technology of Advanced Materials is devoted to the research into such 'organic conductors'The first organic metal was (TTF(TCNQ, which was found in 1973 to have high conductivity at room temperature and a metal–insulator transition at low temperatures. The first organic superconductor was (TMTSF2PF6, whose superconductivity under high pressures was reported by J´erome in 1980. After these findings, the research on organic conductors exploded. Hundreds of organic conductors have been reported, among which more than one hundred exhibit superconductivity. Recently, a single-component organic conductor has been found with metallic conductivity down to low temperatures.In these organic conductors, in spite of their simple electronic structures, much new physics has arisen from the low dimensionality. Examples are charge and spin density waves, characteristic metal–insulator transitions, charge order, unconventional superconductivity, superconductor–insulator transitions, and zero-gap conductors with Dirac cones. The discovery of this new physics is undoubtedly derived from the development of many intriguing novel organic conductors. High quality single crystals are indispensable to the precise measurement of electronic states.This focus issue

  1. Transparent electronic conductors

    International Nuclear Information System (INIS)

    This paper discusses how coatings that are both transparent and electrically conducting are important components of most electro-optic devices. These transparent conductors are typically doped, substoichiometric films of oxides of tin, indium, cadmium and zinc. They exhibit high transparency through the visible region out into the near infrared and are good infrared reflectors beyond about 2 microns. Their electrical conductivity can be as high as 5 x 105 Sm-1. Indium tin oxide (ITO) is the transparent conductor most widely used in liquid crystal and electrochromic devices. Transmittance for a 1500 angstrom coating of ITO is about 87% (Illuminant A; photopic detector) with a sheet resistance as low as 12 ohms/square (specific resistivity being 1.8 x 10-6 ohm.m). The concentration of tin dopant in ITO is typically 5 to 10 mole %

  2. The CMS conductor

    CERN Document Server

    Blau, Bertrand; Curé, B; Folch, R; Hervé, A; Horváth, I L; Kircher, F; Musenich, R; Neuenschwander, J; Riboni, P; Seeber, B; Tavares, S; Sgobba, Stefano; Smith, R P

    2002-01-01

    The Compact Muon Solenoid (CMS) is one of the general-purpose detectors to be provided for the LHC project at CERN. The design field of the CMS superconducting magnet is 4 T, the magnetic length is 12.5 m and the free bore is 6 m. The magnetic field is achieved by means of a four-layer superconducting solenoid. The stored magnetic energy is 2.7 GJ at nominal current of 20 kA (at 4.5 K operating temperature). The coil is wound from a high purity aluminum- stabilized Rutherford type conductor. Unlike other existing Al- stabilized thin solenoids, the structural integrity of the CMS coil is ensured both by the Al-alloy reinforcement welded to the conductor and an external support cylinder. The flat NbTi cable is embedded in high purity aluminum by a continuous co-extrusion process. (7 refs).

  3. Physics of superionic conductors

    CERN Document Server

    1979-01-01

    Superionic conductors are solids whose ionic conductivities approach, and in some cases exceed, those of molten salts and electrolyte solutions. This implies an un­ usual state of matter in which some atoms have nearly liquidlike mobility while others retain their regular crystalline arrangement. This liquid-solid duality has much appeal to condensed matter physicists, and the coincident development of powerful new methods for studying disordered solids and interest in superionic conductors for technical applications has resulted in a new surge of activity in this venerable field. It is the purpose of this book to summarize the current re­ search in the physics of superionic conduction. with special emphasis on those aspects which set these materials apart from other solids. The volume is aimed to­ wards the materials community and will, we expect, stimulate further research on these potentially useful substances. The usual characterization of the superionic phase lists high ionic conductivity; low activat...

  4. The CMS conductor

    CERN Document Server

    Horváth, I L; Marti, H P; Neuenschwander, J; Smith, R P; Fabbricatore, P; Musenich, R; Calvo, A; Campi, D; Curé, B; Desirelli, Alberto; Favre, G; Riboni, P L; Sgobba, Stefano; Tardy, T; Sequeira-Lopes-Tavares, S

    2000-01-01

    The Compact Muon Solenoid (CMS) is one of the experiments, which are being designed in the framework of the Large Hadron Collider (LHC) project at CERN, the design field of the CMS magnet is 4 T, the magnetic length is 13 m and the aperture is 6 m. This high magnetic field is achieved by means of a 4 layer, 5 modules superconducting coil. The coil is wound from an Al-stabilized Rutherford type conductor. The nominal current of the magnet is 20 kA at 4.5 K. In the CMS coil the structural function is ensured, unlike in other existing Al-stabilized thin solenoids, both by the Al-alloy reinforced conductor and the external former. In this paper the retained manufacturing process of the 50-km long reinforced conductor is described. In general the Rutherford type cable is surrounded by high purity aluminium in a continuous co-extrusion process to produce the Insert. Thereafter the reinforcement is joined by Electron Beam Welding to the pure Al of the insert, before being machined to the final dimensions. During the...

  5. Oxygen ion conductors

    Directory of Open Access Journals (Sweden)

    Stephen J Skinner

    2003-03-01

    A very interesting subgroup of this class of materials are the oxides that display oxygen ion conductivity. As well as the intrinsic interest in these materials, there has been a continued drive for their development because of the promise of important technological devices such as the solid oxide fuel cell (SOFC, oxygen separation membranes, and membranes for the conversion of methane to syngas1. All of these devices offer the potential of enormous commercial and ecological benefits provided suitable high performance materials can be developed. In this article we will review the materials currently under development for application in such devices with particular reference to some of the newly discovered oxide ion conductors.

  6. 33 CFR 183.425 - Conductors: General.

    Science.gov (United States)

    2010-07-01

    ... Conductors: General. (a) Each conductor must be insulated, stranded copper. (b) Except for intermittent... equipment; electronic circuits having a current flow of less than one ampere; conductors which are...

  7. Interacting with a Virtual Conductor

    NARCIS (Netherlands)

    Bos, P.; Reidsma, D.; Ruttkay, Z.M.; Nijholt, A.; Harper, R.; Rauterberg, M.; Combetto, M.

    2006-01-01

    This paper presents a virtual embodied agent that can conduct musicians in a live performance. The virtual conductor conducts music specified by a MIDI file and uses input from a microphone to react to the tempo of the musicians. The current implementation of the virtual conductor can interact with

  8. GMR of stranded multizone conductors

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y.; Fortin, S.; Ma, J.; Dawalibi, F.P. [Safe Engineering Services and Technologies Ltd., Montreal, PQ (Canada)

    2008-07-01

    This paper presented a newly developed method for the computation of the geometric mean radius (GMR) of stranded conductors of circular cross-section consisting of several zones with distinct electrical properties. The method also accounts for frequency dependence or skin effects. Examples of the use of this method were presented, and were found to be in good agreement with published data. This method can be used to provide more accurate estimates of the GMR for composite conductors made of strands of different size and properties, and also to better calculate the impedance of those conductors at higher frequencies. The conductor can consist of several concentric tubular zones, each containing one or more concentric layers of identical strands. The radius, resistivity and permeability of the strands can be different for each zone. The study considered the effect of the non-uniform current distribution inside the conductor. 4 refs., 3 tabs., 3 figs.

  9. Ontwikkeling van een toets ter bepaling van sublethale effecten van chemische stoffen op regenwormen. II. Reproduktie door de regenwormen Eisenia fetida en Eisenia andrei in een kunstgrond

    NARCIS (Netherlands)

    Gestel CAM van; Dis WA van; Breemen EM van

    1988-01-01

    Nagegaan werd of coconproduktie-experimenten uitgevoerd kunnen worden met de voor acuut toxiciteitsonderzoek met regenwormen aanbevolen kunstgrond en regenwormsoorten. Uiteindelijke doel van het onderzoek is te komen tot een toets waarmee het effect van chemische stoffen op de reproduktie van re

  10. Design of multiband metamaterial absorber based on artificial magnetic conductor

    Science.gov (United States)

    Dang, Kezheng; He, Zijian; Li, Zhigang; Miao, Lei; Liu, Hao

    2015-10-01

    We present a general method to design multiband absorber by replacing the ground plane in a conventional metamaterial absorber with an artificial magnetic conductor. Due to its unique property of in-phase reflection at some specific frequency, the artificial magnetic conductor is used to introduce new absorption in the operation band. Meanwhile, out of the in-phase reflection band, the original absorbing capability of the absorber is reserved. To demonstrate it, we design a metamaterial absorber comprising three layers which are grids patterned resistive frequency selective surface, dielectric layer and the ground plane respectively. With an appropriate design, the absorber performs an absorbing peak at about 10 GHz. Then, we utilize a single band artificial magnetic conductor at 6.25 GHz and a dual-band one at 6.27 GHz and 8.17 GHz, which are both lossy and comprised of patches array varying in periodic size with a thickness of 0.6 mm, to replace the ground plane in the metamaterial absorber separately. The reflectivity of these multiband absorbers are simulated, and experiments are carried out later. Experimental results agree well with the simulations. All results verified that the method presented at the beginning is effective. The results show that additional absorptions exist at the frequencies where microwaves are nearly reflected in phase on the artificial magnetic conductor. Meanwhile the original absorbing capability of the metamaterial absorber has been preserved mostly. Based on the artificial magnetic conductor, the multiband absorber performs better with an increasing absorption bandwidth from 8.5 GHz to 10 GHz compared to the metamaterial absorber.

  11. Special Report: Solid Ionic Conductors.

    Science.gov (United States)

    Shriver, Duward F.; Farrington, Gregory C.

    1985-01-01

    Solid ionic conductors are unusual materials that may find valuable applications in devices ranging from high-energy density batteries to lasers. The nature of these materials and their potential uses are discussed. (JN)

  12. A lithium superionic conductor.

    Science.gov (United States)

    Kamaya, Noriaki; Homma, Kenji; Yamakawa, Yuichiro; Hirayama, Masaaki; Kanno, Ryoji; Yonemura, Masao; Kamiyama, Takashi; Kato, Yuki; Hama, Shigenori; Kawamoto, Koji; Mitsui, Akio

    2011-09-01

    Batteries are a key technology in modern society. They are used to power electric and hybrid electric vehicles and to store wind and solar energy in smart grids. Electrochemical devices with high energy and power densities can currently be powered only by batteries with organic liquid electrolytes. However, such batteries require relatively stringent safety precautions, making large-scale systems very complicated and expensive. The application of solid electrolytes is currently limited because they attain practically useful conductivities (10(-2) S cm(-1)) only at 50-80 °C, which is one order of magnitude lower than those of organic liquid electrolytes. Here, we report a lithium superionic conductor, Li(10)GeP(2)S(12) that has a new three-dimensional framework structure. It exhibits an extremely high lithium ionic conductivity of 12 mS cm(-1) at room temperature. This represents the highest conductivity achieved in a solid electrolyte, exceeding even those of liquid organic electrolytes. This new solid-state battery electrolyte has many advantages in terms of device fabrication (facile shaping, patterning and integration), stability (non-volatile), safety (non-explosive) and excellent electrochemical properties (high conductivity and wide potential window). PMID:21804556

  13. Verhalten klinisch-chemischer und hormonanalytischer Parameter bei Kühen mit und nach einem Prolapsus uteri : Versuch einer Kausalitätsklärung

    OpenAIRE

    Seitz, Klaus

    2008-01-01

    Das Ziel der vorgelegten Arbeit bestand zum einen darin, anhand der Bestimmung klinisch–chemischer und hormonanalytischer Parameter von Rindern, welche an einem Prolapsus uteri erkrankt waren sowie von gesunden Kontrolltieren im gleichen postpartalen Status, Hinweise über die Kausalität dieser Erkrankung zu erlangen. Zum anderen war zu eruieren, ob im Verlauf des Frühpuerperiums bei den betroffenen Tieren anhaltende Imbalanzen bestimmter Stoffwechselparameter bestehen. Weiterhin sollte eine M...

  14. Graphene, a promising transparent conductor

    Directory of Open Access Journals (Sweden)

    Jonathan K. Wassei

    2010-03-01

    Full Text Available New electronic devices such as touch screens, flexible displays, printable electronics, solid-state lighting and thin film photovoltaics have led to a rapidly growing market for flexible transparent conductors. Standard indium tin oxide films are unlikely to satisfy future needs due to losses in conductivity on bending and the escalating cost of indium which is in limited supply. Recent advances in the synthesis and characterization of graphene indicate that it may be suitable for many electronic applications including as a transparent conductor. Graphene hybrids with, for example, carbon nanotubes, may prove to be especially interesting.

  15. Interacting with a Virtual Conductor

    NARCIS (Netherlands)

    Bos, P.

    2007-01-01

    The task of conducting human musicians in a live performance by a computer has not yet been addressed extensively before. A few attempts exist at letting a computer perform this task, but there is no interactive virtual conductor who can conduct human musicians and can interact with these musicians.

  16. High Critical Current Coated Conductors

    Energy Technology Data Exchange (ETDEWEB)

    Paranthaman, M. P.; Selvamanickam, V. (SuperPower, Inc.)

    2011-12-27

    One of the important critical needs that came out of the DOE’s coated conductor workshop was to develop a high throughput and economic deposition process for YBCO. Metal-organic chemical vapor deposition (MOCVD) technique, the most critical steps in high technical micro fabrications, has been widely employed in semiconductor industry for various thin film growth. SuperPower has demonstrated that (Y,Gd)BCO films can be deposited rapid with world record performance. In addition to high critical current density with increased film thickness, flux pinning properties of REBCO films needs to be improved to meet the DOE requirements for various electric-power equipments. We have shown that doping with Zr can result in BZO nanocolumns, but at substantially reduced deposition rate. The primary purpose of this subtask is to develop high current density MOCVD-REBCO coated conductors based on the ion-beam assisted (IBAD)-MgO deposition process. Another purpose of this subtask is to investigate HTS conductor design optimization (maximize Je) with emphasis on stability and protection issues, and ac loss for REBCO coated conductors.

  17. Conductive Mechanism of Organic Conductor

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Organic conductor is a kind of organic compound which has special electronic and magnetic properties. The research of the organic compounds has received considerable attention because of their potential applications in many areas. The molecular conductive units are theoretically investigated as well as their energy gap and charge distribution. The relationship of conductivity and micro-mechanism is discussed.

  18. Flat conductor cable design, manufacture, and installation

    Science.gov (United States)

    Angele, W.; Hankins, J. D.

    1973-01-01

    Pertinent information for hardware selection, design, manufacture, and quality control necessary for flat conductor cable interconnecting harness application is presented. Comparisons are made between round wire cable and flat conductor cable. The flat conductor cable interconnecting harness systems show major cost, weight, and space savings, plus increased system performance and reliability. The design application section includes electrical characteristics, harness design and development, and a full treatise on EMC considerations. Manufacturing and quality control sections pertain primarily to the developed conductor-contact connector system and special flat conductor cable to round wire cable transitions.

  19. Nonlinear optical constants of ionic conductors: a study based on the Sheik-Bahae equation

    International Nuclear Information System (INIS)

    Guided by the prediction of the bond fluctuation model of superionic conductors, the relation between the nonlinear optical constants and the ion transport properties in ionic conductors has been studied. Since the measured values of nonlinear optical constants in ionic conductors are very limited, they have been evaluated through the Sheik-Bahae equation. Using such values, it is shown that the activation energy of ion transport and the superionic transition temperature decrease with the increase of the nonlinear refractive index. It is also pointed out that the band gap energy and the linear refractive index in superionic conductors are relatively weakly correlated when compared with non-superionic materials. The development of a new field of study that could be called photoionics is suggested (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. Nonlinear optical constants of ionic conductors: a study based on the Sheik-Bahae equation

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Shosuke [HUREC, Kumamoto University, 860-8555 Kumamoto (Japan); Aniya, Masaru [Department of Physics, Graduate School of Science and Technology, Kumamoto University, 860-8555 Kumamoto (Japan)

    2012-12-15

    Guided by the prediction of the bond fluctuation model of superionic conductors, the relation between the nonlinear optical constants and the ion transport properties in ionic conductors has been studied. Since the measured values of nonlinear optical constants in ionic conductors are very limited, they have been evaluated through the Sheik-Bahae equation. Using such values, it is shown that the activation energy of ion transport and the superionic transition temperature decrease with the increase of the nonlinear refractive index. It is also pointed out that the band gap energy and the linear refractive index in superionic conductors are relatively weakly correlated when compared with non-superionic materials. The development of a new field of study that could be called photoionics is suggested (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Pulse Propagation on close conductors

    CERN Document Server

    Dieckmann, A

    2001-01-01

    The propagation and reflection of arbitrarily shaped pulses on non-dispersive parallel conductors of finite length with user defined cross section is simulated employing the discretized telegraph equation. The geometry of the system of conductors and the presence of dielectric material determine the capacities and inductances that enter the calculation. The values of these parameters are found using an iterative Laplace equation solving procedure and confirmed for certain calculable geometries including the line charge inside a box. The evolving pulses and the resulting crosstalk can be plotted at any instant and - in the Mathematica notebook version of this report - be looked at in an animation. As an example a differential pair of microstrips as used in the ATLAS vertex detector is analysed.

  2. Graphene, a promising transparent conductor

    OpenAIRE

    Wassei, Jonathan K.; Kaner, Richard B.

    2010-01-01

    New electronic devices such as touch screens, flexible displays, printable electronics, solid-state lighting and thin film photovoltaics have led to a rapidly growing market for flexible transparent conductors. Standard indium tin oxide films are unlikely to satisfy future needs due to losses in conductivity on bending and the escalating cost of indium which is in limited supply. Recent advances in the synthesis and characterization of graphene indicate that it may be suitable for many electr...

  3. Joints for large superconducting conductors

    International Nuclear Information System (INIS)

    Large fusion magnets call for high-current conductors (up to 60 kA). This has been achieved by the cable-in-conduit conductor concept. The connection of these conductors has to take into account several demanding boundary conditions: a large number of strands (around 1000), a low resistance at high current (1-2 nΩ), low losses in pulsed field operation, Nb3Sn heat treatment, helium tightness control, limited available space. A conceptual design was developed by the CEA, based on the connection of two separate twin boxes clamped together, according to the lap-joint concept. These boxes are machined out of an explosive bonding plate (jacket material/copper), and the electrical connection is achieved by tin-lead soldering of the facing copper soles. After qualification of the explosive bond and validation of the joint concept in the laboratory, the technology was transferred to the industry within the framework of the manufacture of the ITER Toroidal Field Model Coil (TFMC). In addition, three full-size joint samples (FSJS), relevant to different jacket materials and joining techniques, were manufactured by the industry and successfully tested in the SULTAN facility at CRPP, Villigen. The paper reports on the results of the laboratory tests, describes the transfer of technology to industry, and lastly presents some typical experimental results

  4. Temperature limited heater utilizing non-ferromagnetic conductor

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar; Harold J. (Bellaire, TX), Harris; Christopher Kelvin (Houston, TX)

    2012-07-17

    A heater is described. The heater includes a ferromagnetic conductor and an electrical conductor electrically coupled to the ferromagnetic conductor. The ferromagnetic conductor is positioned relative to the electrical conductor such that an electromagnetic field produced by time-varying current flow in the ferromagnetic conductor confines a majority of the flow of the electrical current to the electrical conductor at temperatures below or near a selected temperature.

  5. Herstellung eines Phaffia rhodozyma : Stamms mit verstärkter Astaxanthin-Synthese über gezielte genetische Modifikation chemisch mutagenisierter Stämme

    OpenAIRE

    Gassel, Sören

    2014-01-01

    Ziel dieser Arbeit war es erstmals durch eine Kombination aus chemischer Mutagenese und gezielter genetischer Modifikation (hier: „metabolic engineering“) einen Phaffia-Stamm herzustellen, welcher über die Mutagenese hinaus über eine weiter verstärkte Astaxanthin-Synthese verfügt. Die von „DSM Nutritional Products“ bereitgestellten chemischen Mutanten wurden analysiert und über einen Selektionsprozess auf Pigmentstabilität und Wachstum hin optimiert, da die Stämme aus cryogenisierter Dauer...

  6. Präparation spezieller Biokatalysatoren für die chemisch-technische Nutzung zur Bereitstellung von Aromaten und chiralen α-Hydroxyketonen

    OpenAIRE

    Bieler, Nora Christiane

    2011-01-01

    Teil 1 Bereitstellung der Biokatalysatoren LAC, LiP und MnP für deren chemisch-technische Nutzung Die drei Oxidoreduktasen Laccase (LAC), Lignin- und Manganperoxidase (Li- und MnP) aus Weißfäulepilzen sind technisch sehr interessant, da sie unter Anderem Lignin abbauen können. Vor allem deren zeitaufwändige Produktion in den ligninolytischen Organismen limitiert jedoch industrielle Anwendungen. Daher wurden Möglichkeiten zur Bereitstellung dieser Biokatalysatoren überprüft. So war es Ziel, di...

  7. Ku-band HTS filters with narrow and wide bands for space communications

    International Nuclear Information System (INIS)

    We report the designing and simulation results of the HTS band-pass filters for Ku band with different bandwidths of 0.08 and 0.5 GHz, in comparison with the same shape filters using normal conductors as the circuit conductors of the filter resonator. The examination results of the fabricated filter samples are compared with the filtering characteristics of S parameters. In the case of the narrower band, the simulation results of the planer-circuit-type filter which consists of resonators showed the filtering characteristics that strongly depend on the coupling coefficients and the resonant frequency of each resonator mutually. It is confirmed that the HTS planer circuit filters for Ku band exhibited unloaded Q with the volume of about 10 cm3 greater than that of the normal conductor with the same structure

  8. Vertical exchange and chemical conversion of trace elements over topographically complex terrain; Vertikaler Austausch und chemische Umwandlung von Spurenstoffen ueber topographisch gegliedertem Gelaende

    Energy Technology Data Exchange (ETDEWEB)

    Kuntze, K.

    2001-10-01

    The influence of topography on the vertical exchange of trace elements was investigated with the aid of a numeric simulation model. It is a couopled 3D model consisting of the mesoscale model KAMM and the dispersion model DRAIS, extended by the gaseous phase mechanism of the RADM model. This way, both meteorological and chemical processes can be analyzed in a preselected time and spatial resolution. The simulations were validated by a comparison with measurements made during the TRACT campaign. Satisfactory agreement between the two was established. [German] In der vorliegenden Arbeit wurde der Einfluss der Topographie auf den vertikalen Austausch von Spurenstoffen mit Hilfe eines numerischen Simulationsmodells untersucht. Bei dem Simulationsmodell handelt es sich um ein dreidimensionales gekoppeltes Modell, welches aus dem mesoskaligen Modell KAMM und dem um den Gasphasenmechanismus des RADM-Modells erweiterten Ausbreitungsmodell DRAIS besteht. Mit diesem Modellsystem war es moeglich, sowohl meterologische als auch chemische Prozesse in einer vorher gewaehlten zeitlichen und raeumlichen Aufloesung zu betrachten. Um die Qualitaet der Simulation und damit deren Verwendbarkeit fuer die Untersuchungen festzustellen, wurde ein Vergleich mit Messungen durchgefuehrt. Dazu wurden berechnete meterologische und chemische Groessen mit den waehrend der Feldmesskampagne TRACT gemessenen Groessen verglichen. Der Vergleich der simulierten Groessen sowohl mit Radiosondenaufstiegen als auch mit Zeitreihen und Flugzeugmessungen lieferte eine gute Uebereinstimmung. (orig.)

  9. Assessment of sodium conductor distribution cable

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-06-01

    The study assesses the barriers and incentives for using sodium conductor distribution cable. The assessment considers environmental, safety, energy conservation, electrical performance and economic factors. Along with all of these factors considered in the assessment, the sodium distribution cable system is compared to the present day alternative - an aluminum conductor system. (TFD)

  10. Analytical characterization of technical animal fat from a rendering plant; Chemisch-analytische Charakterisierung technischen tierischen Fettes aus einer Tierkoerperbeseitigungsanstalt

    Energy Technology Data Exchange (ETDEWEB)

    Bahadir, M.; Jopke, P.; Matthies, B.; Schmidt-Naedler, C.; Wichmann, H. [Technische Univ. Braunschweig (Germany). Inst. fuer Oekologische Chemie und Abfallanalytik; Bock, R.; Dettmer, T.; Hesselbach, J. [Technische Univ. Braunschweig (Germany). Inst. fuer Werkzeugmaschinen und Fertigungstechnik; Falk, O.; Meyer-Pittroff, R. [Technische Univ. Muenchen, Freising-Weihenstephan (Germany). Lehrstuhl fuer Energie- und Umwelttechnik der Lebensmittelindustrie

    2004-07-01

    Aims and Scope. German rendering plants produce 300,000 tons of animal fat per year. Until recently, these raw products have been in wide use as nutritional additive for cattle and other animals fodder but now they have been banned due to their assumed role in BSE infection. Therefore, alternative fields of usage are required. In this context the Deutsche Bundesstiftung Umwelt (DBU) is sponsoring a joint research project which deals with the production and testing of cooling lubricants based on animal fat esters. Methods. In a first step, characteristics and quality of the animal fat were analyzed and monitored for a whole year in order to identify e.g. seasonal variations. The investigations covered the following fat specific and trace analytical parameters: total contamination, sulfates ash, water content, peroxide number, iodine value, kinematical viscosity, neutralisation number (free fatty acids), fatty acid spectra, elements / heavy metals (Al, B, Ca, Cd, Cr, Cu, Fe, K, Mo, Mn, Na, Ni, P, Pb, S, Sn, V, W and Zn), polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-dioxins and polychlorinated dibenzofurans. Results. Valuable hints on the design of the technical process of fatty acid methylesters production were gained by regarding the fat specific parameters. (orig.) [German] Hintergrund und Ziel. Von den deutschen Tierkoerperbeseitigungsanstalten werden z.Z. rund 300.000 t/a technisches tierisches Fett produziert. Ausgeloest durch die BSE-Krise wird dieser Rohstoff nicht mehr als Tierfutterergaenzungsmittel eingesetzt. Nun wird nach neuen Verwertungswegen fuer diese Fette gesucht. In diesem Zusammenhang wird von der DBU ein Verbundprojekt finanziert, in dessen Rahmen durch Umesterung der Fette Grundoele fuer Kuehlschmierstoffe (KSS) hergestellt und die KSS-Produkte in der spanenden Bearbeitung von Metallen in der industriellen Praxis getestet werden sollen. Methoden. Als erster Schritt sollten durch chemisch

  11. Comparison of hyperbolic and hyperboloid conductor electrostatics

    Science.gov (United States)

    Lekner, John

    2006-01-01

    The potentials and fields of hyperbolic and hyperboloidal conductors are available analytically. A detailed comparison of the two-dimensional and three-dimensional problems shows strong similarities, but also interesting differences. The electric field near a hyperboloidal needle is stronger (ceteris paribus) than near a hyperbolic blade, and dies off faster. The field at the hyperbolic conductor varies as the 1/3 power of the local curvature. At the hyperboloid conductor the field varies as the 1/4 power of the local Gaussian curvature (which is the product of the two principal curvatures).

  12. Radioactive lightning conductors: protection or danger?

    International Nuclear Information System (INIS)

    The present article describes the various aspects involved in the utilization of radioactive material in lightning conductors, in particular the main reasons and arguments that gave support to the decision taking concerning the interruption of this practice in Brazil. It is pointed out that although the risks associated with the presence of Am-241 in lightning conductors is small, there is no in technical evidence to justify the superiority of such devices, when compared to conventional ones. (author)

  13. Casimir force between sharp-shaped conductors

    OpenAIRE

    Maghrebi, Mohammad F.; Rahi, Sahand Jamal; Emig, Thorsten; Graham, Noah; Jaffe, Robert L.; Kardar, Mehran

    2010-01-01

    Casimir forces between conductors at the sub-micron scale cannot be ignored in the design and operation of micro-electromechanical (MEM) devices. However, these forces depend non-trivially on geometry, and existing formulae and approximations cannot deal with realistic micro-machinery components with sharp edges and tips. Here, we employ a novel approach to electromagnetic scattering, appropriate to perfect conductors with sharp edges and tips, specifically to wedges and cones. The interactio...

  14. A Psychophysiological Case Study of Orchestra Conductors.

    Science.gov (United States)

    Jaque, S Victoria; Karamanukyan, Isabel H; Thomson, Paula

    2015-12-01

    The psychological and physiological effects of performance were investigated in two professional orchestral conductors, with data collected prior to, during, and after a rehearsal and a public performance. The participants were given a battery of psychological self-report tests (anxiety, dissociation, health inventory, fantasy proneness, shame, and flow). Ambulatory physiological monitoring (Vivometric LifeShirt® system) was conducted during both a rehearsal and public performance to gather information about the autonomic nervous system and heart rate variability (HRV). One conductor had a history of asthma and anxiety, and the second conductor had coronary artery disease. The results revealed within-subject and between-subject differences in autonomic nervous system responses and HRV during several conditions (pre-performance rest, stair-climbing, rehearsal, and performance). Based on heart rate, the physiological demands of professional conducting are reflective of work intensities considered "hard." Both conductors experienced high flow states. Anxiety and coronary artery disease may have attenuated HRV resilience in this study. It is recommended that noninvasive methods be implemented to assess cardiac autonomic activity in professional conductors, particularly during engagement in their professional activities. The findings suggest a need to further study anxiety, respiratory conditions, and cardiovascular risks for conductors. PMID:26614972

  15. Development of manufacturing technologies for ITER toroidal field coil conductors

    International Nuclear Information System (INIS)

    The Japan Atomic Energy Agency (JAEA) is responsible for procuring 25% of the ITER toroidal field (TF) coil conductors as the Japanese Domestic Agency (JADA) for the ITER project. The TF conductor is a circular shaped, cable-in-conduit conductor, composed of a cable and a stainless-steel conduit (jacket). The outer diameter and maximum length of the TF conductor are 43.7 mm and 760 m, respectively. JAEA has constructed a new conductor manufacturing facility. Prior to starting the conductor manufacturing, JAEA manufactured a 760 m-long Cu dummy conductor as a conductor manufacturing process qualification, such as processes of welding, cable insertion, compaction and spooling. All manufacturing processes have been qualified and JAEA has started to fabricate superconducting conductors for the TF coils. (author)

  16. Conductor shape optimisation using thermographic imaging

    International Nuclear Information System (INIS)

    An important consideration in the design of high frequency electromagnetic devices is the effect of conductor shape on current distribution. As a rule of thumb, at high frequency the cross-sectional current distribution resembles a charge distribution in a charged conductor, with current travelling along the surface and particularly along edges. However when other conductors are present the current distribution may change dramatically. At BHP Research some novel electromagnetic devices are being developed. While the details are proprietary, in one of these the current distribution is an important factor in determining the ultimate performance of the device. Thus we required an experimental technique to analyse the current path. Thermographic imaging was considered because heating is proportional to I2. The conductors carry very high currents (thousands of ampere) at high frequencies (thousands of hertz) and are water cooled through their hollow centers. Two conductor profiles were tested; circular and rectangular. Calculated current distribution in a finite element model showed the landscape design as being the most efficient current carrier

  17. Spectroscopic signatures of spin-charge separation in the quasi-one-dimensional organic conductor TTF-TCNQ

    DEFF Research Database (Denmark)

    Claessen, R.; Sing, M.; Schwingenschlogl, U.; Blaha, P.; Dressel, M.; Jacobsen, Claus Schelde

    2002-01-01

    The electronic structure of the quasi-one-dimensional organic conductor TTF-TCNQ is studied by angle-resolved photoelectron spectroscopy (ARPES). The experimental spectra reveal significant discrepancies to band theory. We demonstrate that the measured dispersions can be consistently mapped onto...

  18. Properties and applications of perovskite proton conductors

    International Nuclear Information System (INIS)

    A brief overview is given of the main types and principles of solid-state proton conductors with perovskite structure. Their properties are summarized in terms of the defect chemistry, proton transport and chemical stability. A good understanding of these subjects allows the manufacturing of compounds with the desired electrical properties, for application in renewable and sustainable energy devices. A few trends and highlights of the scientific advances are given for some classes of protonic conductors. Recent results and future prospect about these compounds are also evaluated. The high proton conductivity of barium cerate and zirconate based electrolytes lately reported in the literature has taken these compounds to a highlight position among the most studied conductor ceramic materials. (author)

  19. Properties and applications of perovskite proton conductors

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Eduardo Caetano Camilo de; Muccillo, Reginaldo, E-mail: ecsouza@ipen.b [Energy and Nuclear Research Institute (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Center of Science and Technology of Materials

    2010-07-01

    A brief overview is given of the main types and principles of solid-state proton conductors with perovskite structure. Their properties are summarized in terms of the defect chemistry, proton transport and chemical stability. A good understanding of these subjects allows the manufacturing of compounds with the desired electrical properties, for application in renewable and sustainable energy devices. A few trends and highlights of the scientific advances are given for some classes of protonic conductors. Recent results and future prospect about these compounds are also evaluated. The high proton conductivity of barium cerate and zirconate based electrolytes lately reported in the literature has taken these compounds to a highlight position among the most studied conductor ceramic materials. (author)

  20. Reinforced aluminium conductor for cryogenic applications

    International Nuclear Information System (INIS)

    Extreme purity aluminum has very attractive electrical properties at temperatures below 25 K which makes it competitive with conventional superconductors for cryogenic applications. Besides its inherently low density, its resistivity decreases by several orders of magnitude over its room temperature value thus making it suitable for use in lightweight high current density devices. This paper describes the fabrication of a 99.999% aluminum conductor reinforced by a powder metallurgy (P/M) processed Al-Fe-Ce alloy. Long continuous lengths of composite conductors consisting of 1, 4 and 19 Al filaments have been produced by streamline die hot extrusion and cold working by conventional wire drawing or cold hydrostatic extrusion. Microstructural observations and some limited electrical resistivity and mechanical property data are presented along with an analysis of the contamination of high purity Al conductors by diffusion during annealing

  1. Properties and applications of perovskite proton conductors

    Directory of Open Access Journals (Sweden)

    Eduardo Caetano Camilo de Souza

    2010-09-01

    Full Text Available A brief overview is given of the main types and principles of solid-state proton conductors with perovskite structure. Their properties are summarized in terms of the defect chemistry, proton transport and chemical stability. A good understanding of these subjects allows the manufacturing of compounds with the desired electrical properties, for application in renewable and sustainable energy devices. A few trends and highlights of the scientific advances are given for some classes of protonic conductors. Recent results and future prospect about these compounds are also evaluated. The high proton conductivity of barium cerate and zirconate based electrolytes lately reported in the literature has taken these compounds to a highlight position among the most studied conductor ceramic materials.

  2. Challenges and status of ITER conductor production

    Science.gov (United States)

    Devred, A.; Backbier, I.; Bessette, D.; Bevillard, G.; Gardner, M.; Jong, C.; Lillaz, F.; Mitchell, N.; Romano, G.; Vostner, A.

    2014-04-01

    Taking the relay of the large Hadron collider (LHC) at CERN, ITER has become the largest project in applied superconductivity. In addition to its technical complexity, ITER is also a management challenge as it relies on an unprecedented collaboration of seven partners, representing more than half of the world population, who provide 90% of the components as in-kind contributions. The ITER magnet system is one of the most sophisticated superconducting magnet systems ever designed, with an enormous stored energy of 51 GJ. It involves six of the ITER partners. The coils are wound from cable-in-conduit conductors (CICCs) made up of superconducting and copper strands assembled into a multistage cable, inserted into a conduit of butt-welded austenitic steel tubes. The conductors for the toroidal field (TF) and central solenoid (CS) coils require about 600 t of Nb3Sn strands while the poloidal field (PF) and correction coil (CC) and busbar conductors need around 275 t of Nb-Ti strands. The required amount of Nb3Sn strands far exceeds pre-existing industrial capacity and has called for a significant worldwide production scale up. The TF conductors are the first ITER components to be mass produced and are more than 50% complete. During its life time, the CS coil will have to sustain several tens of thousands of electromagnetic (EM) cycles to high current and field conditions, way beyond anything a large Nb3Sn coil has ever experienced. Following a comprehensive R&D program, a technical solution has been found for the CS conductor, which ensures stable performance versus EM and thermal cycling. Productions of PF, CC and busbar conductors are also underway. After an introduction to the ITER project and magnet system, we describe the ITER conductor procurements and the quality assurance/quality control programs that have been implemented to ensure production uniformity across numerous suppliers. Then, we provide examples of technical challenges that have been encountered and

  3. Velocity measurement of conductor using electromagnetic induction

    International Nuclear Information System (INIS)

    A basic technology was investigated to measure the speed of conductor by non-contact electromagnetic method. The principle of the velocity sensor was electromagnetic induction. To design electromagnet for velocity sensor, 2D electromagnetic analysis was performed using FEM software. The sensor output was analyzed according to the parameters of velocity sensor, such as the type of magnetizing currents and the lift-off. Output of magnetic sensor was linearly depended on the conductor speed and magnetizing current. To compensate the lift-off changes during measurement of velocity, the other magnetic sensor was put at the pole of electromagnet.

  4. Sistemas Avanzados de Asistencia al Conductor

    OpenAIRE

    Jimenez Ruiz, Francisco; Gómez Casado, Oscar; Naranjo Hernández, José Eugenio; Serradilla García, Francisco; López, José María; Martín, Ángel

    2011-01-01

    El control inteligente de vehículos autónomos es uno de los retos actuales más importantes de los Sistemas Inteligentes de Transporte. La aplicación de técnicas de inteligencia artificial para la gestión automática de los actuadores del vehículo permite a los diferentes sistemas avanzados de asistencia al conductor (ADAS) y a los sistemas de conducción autónoma, realizar una gestión de nivel bajo de una manera muy similar a la de los conductores humanos, mejorando la seguridad y el confor...

  5. Challenges and status of ITER conductor production

    International Nuclear Information System (INIS)

    Taking the relay of the large Hadron collider (LHC) at CERN, ITER has become the largest project in applied superconductivity. In addition to its technical complexity, ITER is also a management challenge as it relies on an unprecedented collaboration of seven partners, representing more than half of the world population, who provide 90% of the components as in-kind contributions. The ITER magnet system is one of the most sophisticated superconducting magnet systems ever designed, with an enormous stored energy of 51 GJ. It involves six of the ITER partners. The coils are wound from cable-in-conduit conductors (CICCs) made up of superconducting and copper strands assembled into a multistage cable, inserted into a conduit of butt-welded austenitic steel tubes. The conductors for the toroidal field (TF) and central solenoid (CS) coils require about 600 t of Nb3Sn strands while the poloidal field (PF) and correction coil (CC) and busbar conductors need around 275 t of Nb–Ti strands. The required amount of Nb3Sn strands far exceeds pre-existing industrial capacity and has called for a significant worldwide production scale up. The TF conductors are the first ITER components to be mass produced and are more than 50% complete. During its life time, the CS coil will have to sustain several tens of thousands of electromagnetic (EM) cycles to high current and field conditions, way beyond anything a large Nb3Sn coil has ever experienced. Following a comprehensive R and D program, a technical solution has been found for the CS conductor, which ensures stable performance versus EM and thermal cycling. Productions of PF, CC and busbar conductors are also underway. After an introduction to the ITER project and magnet system, we describe the ITER conductor procurements and the quality assurance/quality control programs that have been implemented to ensure production uniformity across numerous suppliers. Then, we provide examples of technical challenges that have been

  6. The Novel Microwave Stop-Band Filter

    OpenAIRE

    Chernobrovkin, R. E.; Ivanchenko, I. V.; Korolev, A. M.; Popenko, N. A.; K. Yu. Sirenko

    2008-01-01

    The stop-band filter with the new band-rejection element is proposed. The element is a coaxial waveguide with the slot in the centre conductor. In the frame of this research, the numerical and experimental investigations of the amplitude-frequency characteristics of the filter are carried out. It is noted that according to the slot parameters the two typical resonances (half-wave and quarter-wave) can be excited. The rejection band of the single element is defined by the width, depth, and die...

  7. Electrodynamic Stability Computations for Flexible Conductors of the Aerial Lines

    OpenAIRE

    I. I. Sergey; Y. G. Panamarenka; P. I. Klimkovich; A. P. Dolin; Y. V. Potachits

    2015-01-01

    In aerial transmission lines aluminium multiwire conductors are in use. Owing to their flexible design the electrodynamic effect of short circuit currents may lead to intolerable mutual rendezvous and even cross-whipping of the phase conductors. The increasing motion of the conductors caused by effect of the short-circuit electrodynamic force impulse is accompanied by the dynamic load impact affecting the conductors, insulating and supporting constructions of the aerial lines. Intensity of th...

  8. What is the actual conductor temperature on Power Lines

    OpenAIRE

    Balghouzal, Salima; Lilien, Jean-Louis; El Adnani, Mustapha

    2013-01-01

    This paper will focus on power lines conductor temperature recording owing to smart sensor which is giving access to behaviour of power line span. Laboratory testing heating up HTLS (high temperature low sag) conductor up to 200°C with a smart sensor installed on the conductor is detailed. Peer reviewed

  9. High-temperature superconducting conductors and cables

    International Nuclear Information System (INIS)

    This is the final report of a 3-year LDRD project at LANL. High-temperature superconductivity (HTS) promises more efficient and powerful electrical devices such as motors, generators, and power transmission cables; however this depends on developing HTS conductors that sustain high current densities Jc in high magnetic fields at temperatures near liq. N2's bp. Our early work concentrated on Cu oxides but at present, long wire and tape conductors can be best made from BSCCO compounds with high Jc at low temperatures, but which are degraded severely at temperatures of interest. This problem is associated with thermally activated motion of magnetic flux lines in BSCCO. Reducing these dc losses at higher temperatures will require a high density of microscopic defects that will pin flux lines and inhibit their motion. Recently it was shown that optimum defects can be produced by small tracks formed by passage of energetic heavy ions. Such defects result when Bi is bombarded with high energy protons. The longer range of protons in matter suggests the possibility of application to tape conductors. AC losses are a major limitation in many applications of superconductivity such as power transmission. The improved pinning of flux lines reduces ac losses, but optimization also involves other factors. Measuring and characterizing these losses with respect to material parameters and conductor design is essential to successful development of ac devices

  10. Strain effect in REBCO coated conductors

    International Nuclear Information System (INIS)

    The strain effect on critical current (Ic) in REBCO coated conductors has been intensively investigated owing to its importance for practical applications. The change in Ic with applied strain can be divided into two phenomena; namely reversible variation within elastic deformation for superconducting film, and irreversible degradation related to brittle fracture. REBCO coated conductor is the first material among various high temperature superconductors in which the non-linear reversible change in Ic with uniaxial strain is markedly observed. High stress (strain) tolerance in coated conductors is one of the advantages compared with other superconducting composites, and there are high expectations for application to high-field magnets based on such superior mechanical properties. In this review article, recent research results on the mechanical properties of REBCO coated conductors are summarized, including the stress-strain characteristic for substrate materials, the strain effect on Ic and the experimental techniques for evaluating these properties. Delamination has been recognized as one of the most critical issues for coil applications. Several evaluation methods for delamination strength and interlaminar fracture toughness were introduced. (author)

  11. The Conductor as a Transformational Leader.

    Science.gov (United States)

    Armstrong, Susan; Armstrong, Scott

    1996-01-01

    Identifies charisma and inspirational leadership as the most important characteristics of transformational leaders. Discusses how middle and secondary school music conductors can use the transformational leadership model. Summarizes key components of this model including positive modeling, sharing vision, and empowering others. Provides relevant…

  12. The effects of the proposed green taxation policy on the competitiveness of basic chemical materials; Auswirkungen der geplanten Oekosteuer auf die Wettbewerbsfaehigkeit chemischer Grundprodukte

    Energy Technology Data Exchange (ETDEWEB)

    Maier, K.H. [DEGUSSA Deutsche Gold- und Silber-Scheideanstalt, Frankfurt am Main (Germany); Thomas, G. [Verband der Chemischen Industrie e.V., Frankfurt am Main (Germany)

    1999-06-01

    The authors of this contribution, representatives of the chemical industry, investigated probable effects of the green taxes proposed by the new government of Germany, on the economics of a variety of basic chemical feedstocks. Although the study discussed here was based on the initial draft of a green taxation scheme presented by the coalition of SPD and the Greens now in power, it may as well be used as a reference for assessment of impacts to be expected from recent, amended proposals or any more to come, as it contains a comprehensive analysis of production costs involved for the German industry and industries abroad. (orig./CB) [Deutsch] Die Autoren Karl Heinrich Maier und Dr. Guenther Thomas, beide Vertreter der chemischen Industrie, untersuchten die Auswirkungen einer Oekosteuer auf die Wirtschaftlichkeit unterschiedlicher chemischer Produkte. Als Basis ihrer Ueberlegungen diente ihnen der urspruengliche Gesetzentwurf von SPD und Buendnis 90/Die Gruenen. Aber auch fuer die Bewertung aktueller und zukuenftiger Entwuerfe der Regierungskoalition bildet der Beitrag mit seinen ausfuehrlichen Kostenvergleichen der Produktionen im In- und Ausland eine hervorragende Grundlage. (orig.)

  13. EDITORIAL: Coated conductors and their applications Coated conductors and their applications

    Science.gov (United States)

    Freyhardt, Herbert C.; Lee, Dominic; Izumi, Teruo

    2010-01-01

    The attractive perspectives offered by coated conductors, known as the 2nd generation of high temperature superconductors (2G-HTS), have triggered broad and fruitful R&D efforts to make them ready for the marketplace. The anisotropic features of YBCO and its weak-link behavior require the processing of almost single crystalline thin films into flat tapes of coated conductors by basically two different methods: RABiTS—rolling-assisted biaxially textured substrates; and IBAD—ion-beam assisted deposition. Reliable processing technologies are now at hand, and critical current carrying capacities can be raised to almost 10-20% of the theoretically possible limit by optimizing current transfer through grain boundaries as well as flux pinning through control and design of the microstructural landscapes. The optimization of the in-field properties of the 2G-HTS wires, as well as the manufacturing of coated conductors with low ac losses and of assembled conductors for high current application remain active development areas. Cost reduction and more economic processing are still an issue. However, coated conductors are now beginning to penetrate the market, particularly for power and electrical applications, where savings in energy are essential and where the unique features of high temperature superconducting materials can be utilized. Major international conferences have followed up the progress in this exciting realm, and important workshops and discussion meetings have been held on this topic. Nonetheless, it was felt that a concise and up-to-date issue of Superconductor Science and Technology would be most welcome to summarize and collect the latest developments in processing and characterizing coated conductors, as well as drawing attention to the most innovative applications. The Guest Editors of this focus issue owe great thanks to those colleagues who were willing to contribute with their most recent findings to this issue on 'Coated conductors and their

  14. Casimir force between sharp-shaped conductors

    CERN Document Server

    Maghrebi, Mohammad F; Emig, Thorsten; Graham, Noah; Jaffe, Robert L; Kardar, Mehran

    2010-01-01

    Casimir forces between conductors at the sub-micron scale cannot be ignored in the design and operation of micro-electromechanical (MEM) devices. However, these forces depend non-trivially on geometry, and existing formulae and approximations cannot deal with realistic micro-machinery components with sharp edges and tips. Here, we employ a novel approach to electromagnetic scattering, appropriate to perfect conductors with sharp edges and tips, specifically to wedges and cones. The interaction of these objects with a metal plate (and among themselves) is then computed systematically by a multiple-scattering series. For the wedge, we obtain analytical expressions for the interaction with a plate, as functions of opening angle and tilt, which should provide a particularly useful tool for the design of MEMs. Our result for the Casimir interactions between conducting cones and plates applies directly to the force on the tip of a scanning tunneling probe; the unexpectedly large temperature dependence of the force ...

  15. Current diffusion in rail-gun conductors

    International Nuclear Information System (INIS)

    A method has been developed to analyze one- and two-dimensional, nonlinear current diffusion in rail-gun conductors. A nonlinear current-diffusion equation that accounts for the temperature dependence of electrical conductivity has been developed from Maxwell's equations. A finite-difference heat-transfer computer program was adapted to solve the current-diffusion and thermal-diffusion problems for rail-gun conductors in one and two dimensions. The nonlinear current-diffusion equation was also extended to account for the magnetic-field dependence of the magnetic permeability, thus allowing ferromagnetic materials to be considered. A one-dimensional finite-difference technique was developed for ferromagnetic materials. Two one-dimensional test problems that compare results with other analyses are discussed. A series of calculations of current density and rail temperature was done for various size rectangular rails. One analysis of current diffusion in a ferromagnetic material was also performed

  16. Design and Simulation of Edge-Coupled Stripline Band Pass Filter for U band

    OpenAIRE

    Pawan Shakdwipee

    2013-01-01

    In this paper, a band pass filter structure using Ansoft designer software and Matlab software simulation tool are presented. The filter is operated at U Band range in higher order 50 GHz edge-coupled Stripline band pass filter for different microwave application. For the proposed work we consider simulation using Roger R03203 substrate with dielectric constant of 3.02, Conductor Thickness 0.035 mm and Substrate Height 0.787 mm. This filter is design at a center frequency of 50 GHz with 8 GHz...

  17. AA, inner conductor of a magnetic horn

    CERN Multimedia

    1981-01-01

    At the start-up of the AA and during its initial operation, magnetic horns focused the antiprotons emanating from the production target. These "current-sheet lenses" had a thin inner conductor (for minimum absorption of antiprotons), machined from aluminium to wall thicknesses of 0.7 or 1 mm. The half-sine pulses rose to 150 kA in 8 microsec. The angular acceptance was 50 mrad.

  18. Quantum pumping : coherent rings versus open conductors

    OpenAIRE

    Moskalets, Mykhaylo; Buttiker, Markus

    2003-01-01

    We examine adiabatic quantum pumping generated by an oscillating scatterer embedded in a one-dimensional ballistic ring and compare it with pumping caused by the same scatterer connected to external reservoirs. The pumped current for an open conductor, paradoxically, is non-zero even in the limit of vanishing transmission. In contrast, for the ring geometry the pumped current vanishes in the limit of vanishing transmission. We explain this paradoxical result and demonstrate that the physics u...

  19. Coated conductors for power applications: materials challenges

    International Nuclear Information System (INIS)

    This manuscript reports on the recent progress and the remaining materials challenges in the development of coated conductors (CCs) for power applications and magnets, with a particular emphasis on the different initiatives being active at present in Europe. We first summarize the scientific and technological scope where CCs have been raised as a complex technology product and then we show that there exists still much room for performance improvement. The objectives and CC architectures being explored in the scope of the European project EUROTAPES are widely described and their potential in generating novel breakthroughs emphasized. The overall goal of this project is to create synergy among academic and industrial partners to go well beyond the state of the art in several scientific issues related to CCs’ enhanced performances and to develop nanoengineered CCs with reduced costs, using high throughput manufacturing processes which incorporate quality control tools and so lead to higher yields. Three general application targets are considered which will require different conductor architectures and performances and so the strategy is to combine vacuum and chemical solution deposition approaches to achieve the targeted goals. A few examples of such approaches are described related to defining new conductor architectures and shapes, as well as vortex pinning enhancement through novel paths towards nanostructure generation. Particular emphasis is made on solution chemistry approaches. We also describe the efforts being made in transforming the CCs into assembled conductors and cables which achieve appealing mechanical and electromagnetic performances for power systems. Finally, we briefly mention some outstanding superconducting power application projects being active at present, in Europe and worldwide, to exemplify the strong advances in reaching the demands to integrate them in a new electrical engineering paradigm. (paper)

  20. Electron quantum optics in ballistic chiral conductors

    OpenAIRE

    Bocquillon, E.; Freulon, V.; Parmentier, F. D.; Berroir, J.-M.; Plaçais, B.; Wahl, C.; Rech, J.; Jonckheere, T.; Martin, T; Grenier, C.; Ferraro, D.; Degiovanni, P.; Fève, G.

    2014-01-01

    The edge channels of the quantum Hall effect provide one dimensional chiral and ballistic wires along which electrons can be guided in optics like setup. Electronic propagation can then be analyzed using concepts and tools derived from optics. After a brief review of electron optics experiments performed using stationary current sources which continuously emit electrons in the conductor, this paper focuses on triggered sources, which can generate on-demand a single particle state. It first ou...

  1. A Review of Coated Conductor Development

    Institute of Scientific and Technical Information of China (English)

    徐永利; 时东陆

    2003-01-01

    The developments of coated conductor technology have been reviewed. It is shown that the critical current density of high-Tc wires can begreatly enhanced by using three-fold approaches: grain alignment, grain boundary doping, and optimization of the grain architecture. Major advances have been made in the last16 years mainly in three aspects: substrates, buffer layers and the YBCO layer. Cost is still the main concern for scale up, especially for the approach through vapor depositions, such as the PLD method. TFA-MOD or other CSD methods may be the trend to overcome cost and speed consideration during the scale up. However, high reliability and reproducibility will be the new focus for these techniques. Ni-alloy tapes seem to have advantages over pure Ni in terms of mechanicalstrength and oxidation resistance. Depositing a pure Ni layer on top of Ni-based alloys (such as Ni-Cr and Ni-W alloys) solves the problem of low strength ofNi and poor texture of Ni alloys. The RABiTS and IBAD are the two robust approaches for the texture generation. But the buffer materials and architectures being investigated remain unclear, though CeO2/YSZ/CeO2 and MgO are commonly used buffer layers for RABiTS and IBAD respectively. For the case where a buffer layer isunavoidable, a non-vacuum process would be suitable for low cost and scale up. However, none of the buffer layer fabrication processes through CSD has been demonstrated results good enough for long length coated conductor applications. While, a high Jc superconducting layer can be produced by TFA-MOD, which brings a bright future for coated conductors. Clearly, there are still many scientific and technological barriers to be overcome before any long length of high Jc coated conductor be produced commercially. But theoretical analyses and technological progress show the potential for the practical application of coatedconductor wires in the near future.

  2. Coated conductors for power applications: materials challenges

    Science.gov (United States)

    Obradors, Xavier; Puig, Teresa

    2014-04-01

    This manuscript reports on the recent progress and the remaining materials challenges in the development of coated conductors (CCs) for power applications and magnets, with a particular emphasis on the different initiatives being active at present in Europe. We first summarize the scientific and technological scope where CCs have been raised as a complex technology product and then we show that there exists still much room for performance improvement. The objectives and CC architectures being explored in the scope of the European project EUROTAPES are widely described and their potential in generating novel breakthroughs emphasized. The overall goal of this project is to create synergy among academic and industrial partners to go well beyond the state of the art in several scientific issues related to CCs’ enhanced performances and to develop nanoengineered CCs with reduced costs, using high throughput manufacturing processes which incorporate quality control tools and so lead to higher yields. Three general application targets are considered which will require different conductor architectures and performances and so the strategy is to combine vacuum and chemical solution deposition approaches to achieve the targeted goals. A few examples of such approaches are described related to defining new conductor architectures and shapes, as well as vortex pinning enhancement through novel paths towards nanostructure generation. Particular emphasis is made on solution chemistry approaches. We also describe the efforts being made in transforming the CCs into assembled conductors and cables which achieve appealing mechanical and electromagnetic performances for power systems. Finally, we briefly mention some outstanding superconducting power application projects being active at present, in Europe and worldwide, to exemplify the strong advances in reaching the demands to integrate them in a new electrical engineering paradigm.

  3. Los conductores re-examinados: El transcurso del tiempo deteriora significativamente los conocimientos de los conductores

    Directory of Open Access Journals (Sweden)

    Francisco J. Martos

    2012-01-01

    Full Text Available Dos mil cinco conductores, 1204 hombres y 801 mujeres, una muestra representativa de la población española de conductores, fueron nuevamente examinados utilizando un cuestionario que reproducía fielmente un examen de conducir realizado por la Dirección General de Tráfico (DGT. Las preguntas fueron clasificadas en"“muy importantes", "importantes" y "poco importantes". El 96.5 % de los conductores, suspendió el examen. Los resultados eran tanto peores cuanto más tiempo había transcurridodesde la obtención del permiso de conducir. Esto era independiente de la importancia de las preguntas, de la mayor o menor frecuencia de conducción y afectaba por igual a hombres y mujeres. Las mujeres obtienen mejores puntuaciones en señalización mientras que los hombres son mejores en las preguntas de seguridad vial. Los resultados también demostraban que los conductores profesionales y los de mayor nivel educativo sufren un menor deterioro. Tales resultados nos llevan a considerar la relación que estos datos puedan tener en los niveles de accidentalidad y la conveniencia de establecer pautas para la actualización del conocimiento de los conductores. Finalmente, se discute la relevancia que el examen que se utiliza para obtener el permiso de conducir tiene como indicador o predictor de una futura conducción segura.

  4. HTS twisted stacked-tape cable conductor

    International Nuclear Information System (INIS)

    The feasibility of high field magnet applications of the twisted stacked-tape cabling method with 2G YBCO tapes has been investigated. An analysis of torsional twist strains of a thin HTS tape has been carried out taking into account the internal shortening compressive strains accompanied with the lengthening tensile strains due to the torsional twist. The model is benchmarked against experimental tests using YBCO tapes. The critical current degradation and current distribution of a four-tape conductor was evaluated by taking account of the twist strain, the self-field and the termination resistances. The critical current degradation for the tested YBCO cables can be explained by the perpendicular self-field effect. It is shown that the critical current of a twisted stacked-tape conductor with a four-tape cable does not degrade with a twist pitch length as short as 120 mm. Current distribution among tapes and hysteresis losses are also investigated. A compact joint termination method for a 2G YBCO tape cable has been developed. The twisted stacked-tape conductor method may be an attractive means for the fabrication of highly compact, high current cables from multiple flat HTS tapes.

  5. Testing of the 3M Company Composite Conductor

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, John P [ORNL; Rizy, D Tom [ORNL; Kisner, Roger A [ORNL

    2010-10-01

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum-Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors. The objective of this work is to accelerate the commercial acceptance by electric utilities of this new conductor design by testing four representative conductor classes in controlled conditions. A unique facility called the Powerline Conductor Accelerated Testing (PCAT) Facility was built at ORNL for testing overhead conductors. The PCAT has been uniquely designed for testing overhead bare transmission line conductors at high currents and temperatures after they have been installed and tensioned to the manufacturer's specifications. The ability to operate a transmission line conductor in this manner does not exist elsewhere in the United States. Four classes of ACCR cable designed by the 3M Company have been successfully test at ORNL small, medium, large and small/compact. Based on these and other manufacturer tests, the 3M Company has successfully introduced the ACCR into the commercial market and has completed over twenty installations for utility companies.

  6. Test of ITER conductors in SULTAN: An update

    International Nuclear Information System (INIS)

    The ITER Toroidal Field (TF) conductor qualification phase has been carried out by testing short sample prototype conductors in the SULTAN test facility. This phase, started in 2007, has been substantially completed after minor adjustment of the conductor specification and test procedures. All the parties involved in the TF conductor procurement passed the qualification phase. Starting 2010, the samples for TF process qualification phase are tested in SULTAN. A summary of the results for all the ITER Qualification samples and an updated statistics are presented for the V-I and V-T characteristics of the cable-in-conduit conductors (CICC), including Nb3Sn and NbTi samples assembled with either a 'bottom joint' or a 'U-bend'. The technical improvements of the test facility are reported, including the enhanced cyclic loading rate and the calibration of the current meter. An outlook of the ITER conductor tests in the coming years is also presented.

  7. Fabrication of built-up conductors for large pulsed coils

    International Nuclear Information System (INIS)

    The development work was performed to provide a low-loss, cryostable conductor capable of carrying 5 kA at 3 T for a 30-MJ coil cycled at 0.35 Hz. Much of the work is relevant to conductor development for other pulsed coils, such as a tokamak induction heating coil. As part of the development process, various conductor configurations were subjected to ac loss measurements, stability tests, electrical resistance measurements, and mechanical load-bearing and mechanical fatigue tests. The result is a conductor that appears to satisfy the design criteria with a considerable safety margin

  8. First qualification of ITER Toroidal Field Coil conductor jacketing

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Kazuya, E-mail: hamada.kazuya@jaea.go.jp [Japan Atomic Energy Agency (Japan); Takahashi, Yoshikazu; Isono, Takaaki; Nunoya, Yoshihiko; Matsui, Kunihiro; Kawano, Katsumi; Oshikiri, Masayuki; Tsutsumi, Fumiaki; Koizumi, Norikiyo; Nakajima, Hideo; Okuno, Kiyoshi [Japan Atomic Energy Agency (Japan); Matsuda, Hidemitsu; Yano, Yoshitaka [Nippon Steel Engineering Co. Ltd (Japan); Devred, Arnauld; Bessette, Denis [ITER Organization (France)

    2011-10-15

    The Japan Atomic Energy Agency (JAEA) has the responsibility to procure 25% of the ITER Toroidal Field Coil conductors as the Japanese Domestic Agency (JADA) in the ITER project. The TF conductor is a circular shaped, cable-in-conduit conductor, composed of a cable and a stainless steel conduit (jacket). The outer diameter and maximum length of the TF conductor are 43.7 mm and 760 m, respectively. JAEA started to produce strand, cables and jacket sections and to construct a conductor manufacturing (jacketing) facility in 2008. Following preparation in December 2009 of the jacketing facility, the dummy cable, the jacket sections and fabrication procedures, such as welding, cable insertion, compaction and spooling, JAEA manufactured a 760 m long Cu dummy conductor for process qualification. Into the 760 m long Cu dummy conductor jacketing, JAEA successfully inserted the cable with a maximum force of 32 kN. The outer diameter of the cross section of the spooled conductor was 43.7 {+-} 0.15 mm, which complies with the ITER target requirement of 43.7 {+-} 0.3 mm. Following qualification of all manufacturing processes, JAEA has started to fabricate superconducting conductors for the TF coils.

  9. First qualification of ITER Toroidal Field Coil conductor jacketing

    International Nuclear Information System (INIS)

    The Japan Atomic Energy Agency (JAEA) has the responsibility to procure 25% of the ITER Toroidal Field Coil conductors as the Japanese Domestic Agency (JADA) in the ITER project. The TF conductor is a circular shaped, cable-in-conduit conductor, composed of a cable and a stainless steel conduit (jacket). The outer diameter and maximum length of the TF conductor are 43.7 mm and 760 m, respectively. JAEA started to produce strand, cables and jacket sections and to construct a conductor manufacturing (jacketing) facility in 2008. Following preparation in December 2009 of the jacketing facility, the dummy cable, the jacket sections and fabrication procedures, such as welding, cable insertion, compaction and spooling, JAEA manufactured a 760 m long Cu dummy conductor for process qualification. Into the 760 m long Cu dummy conductor jacketing, JAEA successfully inserted the cable with a maximum force of 32 kN. The outer diameter of the cross section of the spooled conductor was 43.7 ± 0.15 mm, which complies with the ITER target requirement of 43.7 ± 0.3 mm. Following qualification of all manufacturing processes, JAEA has started to fabricate superconducting conductors for the TF coils.

  10. Conductor requirements for high-temperature superconducting utility power transformers

    International Nuclear Information System (INIS)

    High-temperature superconducting (HTS) coated conductors in utility power transformers must satisfy a set of operating requirements that are driven by two major considerations-HTS transformers must be economically competitive with conventional units, and the conductor must be robust enough to be used in a commercial manufacturing environment. The transformer design and manufacturing process will be described in order to highlight the various requirements that it imposes on the HTS conductor. Spreadsheet estimates of HTS transformer costs allow estimates of the conductor cost required for an HTS transformer to be competitive with a similarly performing conventional unit.

  11. AA, Inner Conductor of Magnetic Horn

    CERN Multimedia

    1979-01-01

    Antiprotons emerging at large angles from the production target (hit by an intense 26 GeV proton beam from the PS), were focused into the acceptance of the injection line of the AA by means of a "magnetic horn" (current-sheet lens). Here we see an early protype of the horn's inner conductor, machined from solid aluminium to a thickness of less than 1 mm. The 1st version had to withstand pulses of 150 kA, 15 us long, every 2.4 s. See 8801040 for a later version.

  12. The Novel Microwave Stop-Band Filter

    Directory of Open Access Journals (Sweden)

    R. E. Chernobrovkin

    2008-01-01

    Full Text Available The stop-band filter with the new band-rejection element is proposed. The element is a coaxial waveguide with the slot in the centre conductor. In the frame of this research, the numerical and experimental investigations of the amplitude-frequency characteristics of the filter are carried out. It is noted that according to the slot parameters the two typical resonances (half-wave and quarter-wave can be excited. The rejection band of the single element is defined by the width, depth, and dielectric filling of the slot. Fifth-order Chebyshev filter utilizing the aforementioned element is also synthesized, manufactured, and tested. The measured and simulated results are in good agreement. The experimental filter prototype exhibits the rejection band 0.86 GHz at the level −40 dB.

  13. Multiple band circularly polarized microstrip antenna

    Science.gov (United States)

    Yu, I. P. (Inventor)

    1980-01-01

    A multiple antenna assembly for communicating electromagnetic radiation is disclosed. An antenna element stack is constructed of a plurality of elliptical lamina antenna elements mutally separated by layers of dielectric material, and separated from a ground plane by dielectric material. The antenna assembly is coupled through a feed line in contact with the top antenna element. A conductor joins the remaining antenna elements to the ground plane. Each individual antenna element is operable for communication reception and transmission within a frequency band determined by the size of the particular antenna element. The sizes of the antenna elements may be selected to provide electromagnetic radiation communication over several distinct frequency bands, or to connect the individual bands into a broad band.

  14. Gastric Banding

    Science.gov (United States)

    ... gastric banding before deciding to have the procedure. Advertisements for a device or procedure may not include ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ...

  15. High School Band Students' and Directors' Perceptions of Verbal and Nonverbal Teaching Behaviors

    Science.gov (United States)

    Whitaker, Jennifer A.

    2011-01-01

    This study was designed to examine the use and perception of selected teaching behaviors of high school band directors. Videotaped rehearsals of six band directors' top-performing ensembles were analyzed for conductor magnitude, sequential pattern components, and instructional pacing. Directors and students rated video excerpts of their…

  16. PREFACE: International Symposium on Molecular Conductors: Novel Functions of Molecular Conductors under Extreme Conditions (ISMC 2008)

    Science.gov (United States)

    Takahashi, Toshihiro; Suzumura, Yoshikazu

    2008-02-01

    The International Symposium on Molecular Conductors 2008 (ISMC2008) was held as the second international symposium of the project entitled `Novel Functions of Molecular Conductors under Extreme Conditions', which was supported by the Grant-in-aid for Scientific Research on Priority Areas from the Ministry of Education, Culture, Sports, Science and Technology in Japan. The project lasted from September 2003 to March 2008, and was completed by this symposium held at Okazaki Conference Center, Institute for Molecular Science, Okazaki, Japan (23-25 July 2008), which about 100 scientists attended. During the symposium, five project teams gave summary talks and exciting talks were given on the topics developed recently not only by the members of the project but also by other scientists including invited speakers from abroad, who are doing active research on molecular conductors. It is expected that papers presented in the symposium will give valuable hints for the next step in the research of this field. Therefore the organizers of this symposium decided to publish this proceedings in order to demonstrate these activities, not only for the local community of the project, but also for the broad society of international scientists who are interested in molecular conductors. The editors, who are also the organizers of this symposium, believe that this proceedings provides a significant and relevant contribution to the field of molecular conductors since it is the first time we have published such a proceedings as an electronic journal. We note that all papers published in this volume of Journal of Physics: Conference Series have been peer reviewed by expert referees. Editors made every effort to satisfy the criterion of a proceedings journal published by IOP Publishing. Toshihiro Takahashi and Yoshikazu Suzumura Editors: Toshihiro Takahashi (Gakushuin University) (Chairman) Kazushi Kanoda (University of Tokyo) Seiichi Kagoshima (University of Tokyo) Takehiko Mori (Tokyo

  17. Correlation versus surface effects in photoemission of quasi-1D organic conductors

    DEFF Research Database (Denmark)

    Claessen, R.; Schwingenschlogl, U.; Sing, M.; Jacobsen, Claus Schelde; Dressel, M.

    2002-01-01

    The absence of spectral weight at the Fermi level in photoemission spectra of quasi-1D organic conductors has been interpreted as possible evidence for an unusual many-body state. We demonstrate that great care must be exercised to draw this conclusion exclusively on the basis of a pseudogap. A...... detailed surface characterization of the charge transfer salts (TMTSF)(2)PFt(6) and TTF-TCNQ shows that signatures of electronic correlations in the valence band spectra are strongly affected by surface effects and may even be completely obscured....

  18. Correlation versus surface effects in photoemission of quasi-1D organic conductors

    DEFF Research Database (Denmark)

    Claessen, R.; Schwingenschlogl, U.; Sing, M.; Jacobsen, Claus Schelde; Dressel, M.

    2002-01-01

    The absence of spectral weight at the Fermi level in photoemission spectra of quasi-1D organic conductors has been interpreted as possible evidence for an unusual many-body state. We demonstrate that great care must be exercised to draw this conclusion exclusively on the basis of a pseudogap. A d...... detailed surface characterization of the charge transfer salts (TMTSF)(2)PFt(6) and TTF-TCNQ shows that signatures of electronic correlations in the valence band spectra are strongly affected by surface effects and may even be completely obscured....

  19. Novel processing of HTS based conductors

    Energy Technology Data Exchange (ETDEWEB)

    Ginley, D. S.; Venturini, E. L.; Kwak, J. F.; Baughman, R. J.; Bourcier, R. J.; Mitchell, M. A.; Morosin, B. [Sandia National Labs., Albuquerque, NM (USA); Halloran, J. W.; Neal, M. J. [Ceramics Process Systems Corp., Milford, MA (USA); Capone, D. W. [Supercon, Inc., Shrewsbury, MA (USA)

    1990-01-01

    Conductor development is one of the major long term goals in high temperature superconductor research. In this paper we report on two promising processing technologies that have been utilized to produce superconducting HTS conductors. First, melt spun YBa{sub 2}Cu{sub 3}O{sub 7} fibers rapid thermal processed for 1--8 sec at 950 to 1075{degree}C have {Tc}'s to 92 K, J{sub c}'s to 1100 A/cm{sup 2} and the orthorhombic twinned morphology typical for high quality YBa{sub 2}Cu{sub 3}O{sub 7}. A processing matrix of time, temperature and composition for these fibers shows that slightly CuO-rich starting compositions give the best results. Second, silver tube encapsulated wires of Bi{sub 1.7}Pb{sub 0.3}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} have been made by extrusion, wire drawing and cold rolling. The resulting tapes show orientation of the crystallites, zero resistance up to 100K and improved magnetic hysteresis above 50 K. The combination of mechanical reprocessing and extended thermal anneals near 850{degree}C appears to significantly improve these materials. 13 refs., 7 figs.

  20. Novel processing of HTS based conductors

    International Nuclear Information System (INIS)

    Conductor development is one of the major long term goals in high temperature superconductor research. In this paper the authors report on two promising processing technologies that have been utilized to produce superconducting HTS conductors. First, melt spun YBa2Cu3O7 fibers rapid thermal processed for 1-8 sec at 950 to 1075 degrees C have Tc's to 92 K, Jc to 1100 A/cm2 and the orthorhombic twinned morphology typical for high quality YBa2Cu3O7. A processing matrix of time, temperature and composition for these fibers shows that slightly CuO-rich starting composition give the best results. Second, silver tube encapsulated wires of Bi1.7Pb0.3Sr2Ca2Cu3O10 have been made by extrusion, wire drawing and cold rolling. The resulting tapes show orientation of the crystallites, zero resistance up to 100K and improved magnetic hysteria above 50 K. The combination of mechanical reprocessing and extended thermal anneal near 850 degrees C appears to significantly improve these materials

  1. Conductor gestures influence evaluations of ensemble performance.

    Science.gov (United States)

    Morrison, Steven J; Price, Harry E; Smedley, Eric M; Meals, Cory D

    2014-01-01

    Previous research has found that listener evaluations of ensemble performances vary depending on the expressivity of the conductor's gestures, even when performances are otherwise identical. It was the purpose of the present study to test whether this effect of visual information was evident in the evaluation of specific aspects of ensemble performance: articulation and dynamics. We constructed a set of 32 music performances that combined auditory and visual information and were designed to feature a high degree of contrast along one of two target characteristics: articulation and dynamics. We paired each of four music excerpts recorded by a chamber ensemble in both a high- and low-contrast condition with video of four conductors demonstrating high- and low-contrast gesture specifically appropriate to either articulation or dynamics. Using one of two equivalent test forms, college music majors and non-majors (N = 285) viewed sixteen 30 s performances and evaluated the quality of the ensemble's articulation, dynamics, technique, and tempo along with overall expressivity. Results showed significantly higher evaluations for performances featuring high rather than low conducting expressivity regardless of the ensemble's performance quality. Evaluations for both articulation and dynamics were strongly and positively correlated with evaluations of overall ensemble expressivity. PMID:25104944

  2. Maximum permissible voltage of YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

    2014-06-15

    Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  3. Testing of the 3M Company ACCR Conductor

    Energy Technology Data Exchange (ETDEWEB)

    Stovall, J.P.; RIzy, D.T.; Kisner, R.A.; Deve, H.E. (3M Comp.)

    2010-09-15

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum- Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors so the core has a lower density and higher conductivity. The objective of this work is to accelerate the commercial acceptance by electric utilities of these new conductor designs by testing four representative conductor classes in controlled conditions. Overhead transmission lines use bare aluminum conductor strands wrapped around a steel core strands to transmit electricity. The typical cable is referred to as aluminum-conductor steel-reinforced (ACSR). The outer strands are aluminum, chosen for its conductivity, low weight, and low cost. The center strand is of steel for the strength required to support the weight without stretching the aluminum due to its ductility. The power density of a transmission corridor has been directly increased by increasing the voltage level. Transmission voltages have increased from 115-kV to 765- kV over the past 80 years. In the United States, further increasing the voltage level is not feasible at this point in time, so in order to further increase the power density of a transmission corridor, conductor designs that increase the current carrying capability have been examined. One of the key limiting factors in the design of a transmission line is the conductor sag which determines the clearance of the conductor above ground or underlying structures needed for electrical safety. Increasing the current carrying capability of a conductor increases the joule heating in the conductor which increases the conductor sag. A conductor designed for high-temperature and lowsag operation requires an engineered modification of the conductor materials. To make an advanced cable, the 3M Company solution has been the development of a composite conductor consisting of Nextel ceramic fibers to replace the steel core and

  4. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... stethoscope with electrical conductors. (a) Identification. An esophageal stethoscope with...

  5. Performance evaluation and analysis of ITER poloidal field conductors

    International Nuclear Information System (INIS)

    The performance evaluation and analysis of PF5 conductor of the ITER Project in China have been performed using the Gandalf code (Bottura [1]). This study focuses on the Tcs and MQE of PF5 conductor with Cu–non Cu ratio of 2.3 NbTi strands from WST. The PF5 conductor samples have been measured in SULTAN at CRPP for evaluating the performance successfully. The measurement results are also presented with the evaluation results in the paper. The evaluation results related to Tcs and MQE are agreed well with the measurement results. The simulation with Gandalf code can predict the performance of PF5 conductor effectively and provide the helpful method for ITER conductor design and analysis.

  6. Application of superconductors to center conductor of spherical tokamak reactor

    International Nuclear Information System (INIS)

    The feasibility of superconducting center conductors in spherical tokamaks has been studied. The advantage of superconducting center conductors is evaluated from the view point of loss reduction, increasing q and reduction of required βp. The magnetic field dependence of the critical current density is taken into account. The center conductor is divided radially into several layers, and the operating current density of each layer is optimized. If A > 1.3 and βp > 0.6, the electric power loss can be reduced by the application of superconducting center conductors where κ ∼ 3 and q ∼ 10. In spherical tokamak reactors with low electric power loss, larger q can be attained by the application of superconducting center conductor. In other word, the βp required for the specified q can be reduced. (author)

  7. Photonic band gap structure simulator

    Science.gov (United States)

    Chen, Chiping; Shapiro, Michael A.; Smirnova, Evgenya I.; Temkin, Richard J.; Sirigiri, Jagadishwar R.

    2006-10-03

    A system and method for designing photonic band gap structures. The system and method provide a user with the capability to produce a model of a two-dimensional array of conductors corresponding to a unit cell. The model involves a linear equation. Boundary conditions representative of conditions at the boundary of the unit cell are applied to a solution of the Helmholtz equation defined for the unit cell. The linear equation can be approximated by a Hermitian matrix. An eigenvalue of the Helmholtz equation is calculated. One computation approach involves calculating finite differences. The model can include a symmetry element, such as a center of inversion, a rotation axis, and a mirror plane. A graphical user interface is provided for the user's convenience. A display is provided to display to a user the calculated eigenvalue, corresponding to a photonic energy level in the Brilloin zone of the unit cell.

  8. ELECTRODYNAMIC STABILITY COMPUTATIONS FOR FLEXIBLE CONDUCTORS OF THE AERIAL LINES

    Directory of Open Access Journals (Sweden)

    I. I. Sergey

    2015-01-01

    Full Text Available In aerial transmission lines aluminium multiwire conductors are in use. Owing to their flexible design the electrodynamic effect of short circuit currents may lead to intolerable mutual rendezvous and even cross-whipping of the phase conductors. The increasing motion of the conductors caused by effect of the short-circuit electrodynamic force impulse is accompanied by the dynamic load impact affecting the conductors, insulating and supporting constructions of the aerial lines. Intensity of the short-circuit currents electrodynamic impact on the flexible conductors depends on the short circuit current magnitude. For research into electrodynamic endurance of the conductors of the aerial lines located at the vertices of arbitrary triangle with spans of a large length, the authors assume the conductor analytical model in the form of a flexible tensile thread whose mass is distributed evenly lengthwise the conductor. With this analytical model, by the action of the imposed forces the conductor assumes the form conditioned by the diagram of applied external forces, and resists neither bending nor torsion. The initial conditions calculation task reduces to solving the flexible thread statics equations. The law of motion of the conductor marginal points comes out of the conjoint solution of dynamic equations of the conductor and structural components of the areal electric power lines. Based on the proposed algorithm, the researchers of the Chair of the Electric Power Stations of BNTU developed a software program LINEDYS+, which in its characteristics yields to no foreign analogs, e. g. SAMSEF. To calculate the initial conditions they modified a software program computing the flexible conductor mechanics named MR 21. The conductor short-circuit electrodynamic interaction estimation considers structural elements of the areal lines, ice and wind loads, objective parameters of the short circuit. The software programs are accommodated with the simple and

  9. Microwave Loss Reduction in Cryogenically Cooled Conductors

    CERN Document Server

    Finger, R

    2015-01-01

    Measurements of microwave attenuation at room temperature and 4.2 K have been performed on some conductors commonly used in receiver input circuits. The reduction in loss on cooling is substantial, particularly for copper and plated gold, both of which showed a factor of 3 loss reduction. Copper passivated with benzotriazole shows the same loss as without passivation. The residual resistivity ratio between room temperature and 4.2 K, deduced from the measurements using the classical skin effect formula, was smaller than the measured DC value to a degree consistent with conduction in the extreme anomalous skin effect regime at cryogenic temperatures. The measurements were made in the 5-10 GHz range. The materials tested were: aluminum alloys 1100-T6 and 6061-O, C101 copper, benzotriazole treated C101 copper, and brass plated with electroformed copper, Pur-A-Gold 125-Au soft gold, and BDT200 bright gold.

  10. Random matrix model for disordered conductors

    Indian Academy of Sciences (India)

    Zafar Ahmed; Sudhir R Jain

    2000-03-01

    We present a random matrix ensemble where real, positive semi-definite matrix elements, , are log-normal distributed, $\\exp[-\\log^{2}(x)]$. We show that the level density varies with energy, , as 2/(1 + ) for large , in the unitary family, consistent with the expectation for disordered conductors. The two-level correlation function is studied for the unitary family and found to be largely of the universal form despite the fact that the level density has a non-compact support. The results are based on the method of orthogonal polynomials (the Stieltjes-Wigert polynomials here). An interesting random walk problem associated with the joint probability distribution of the ensuing ensemble is discussed and its connection with level dynamics is brought out. It is further proved that Dyson's Coulomb gas analogy breaks down whenever the confining potential is given by a transcendental function for which there exist orthogonal polynomials.

  11. Plasma Waves and Jets from Moving Conductors

    CERN Document Server

    Gralla, Samuel E

    2016-01-01

    We consider force-free plasma waves launched by the motion of conducting material through a magnetic field. We develop a spacetime-covariant formalism for perturbations of a uniform magnetic field and show how the transverse motion of a conducting fluid acts as a source. We show that fast-mode waves are sourced by the compressibility of the fluid, with incompressible fluids launching a pure-Alfven outflow. Remarkably, this outflow can be written down in closed form, at the nonlinear level, for an arbitrary incompressible flow. The instantaneous flow velocity is imprinted on the magnetic field and transmitted away at the speed of light, carrying detailed information about the conducting source at the time of emission. These results can be applied to transients in pulsar outflows and to jets from neutron stars orbiting in the magnetosphere of another compact object. We discuss jets from moving conductors in some detail.

  12. Irradiation induced disorder in organic conductors

    International Nuclear Information System (INIS)

    We present a brief survey of several recent experimental results concerning the transport properties of irradiated 1D. conductors, and we show that a reasonable knowledge of the mechanisms which account for the changes in the D.C. conductivity either at high or low temperatures has been obtained. These mechanisms are: firstly the 1-D blocking effects of defects and subsequent transverse fixed range phonon activated hopping of single electrons in the metallic regime, and secondly the charge density waves pinning either in the metallic or the insulating regime. As a conclusion we show that it is difficult in most of the cases to distinguish between disorded systems and intrinsic or so-called pure ones

  13. Conductors and Newforms for (1,1)

    Indian Academy of Sciences (India)

    Joshua Lansky; A Raghuram

    2004-11-01

    Let be a non-Archimedean local field whose residue characteristic is odd. In this paper we develop a theory of newforms for (1,1)(), building on previous work on $SL_2(F)$. This theory is analogous to the results of Casselman for $GL_2(F)$ and Jacquet, Piatetski-Shapiro, and Shalika for $GL_n(F)$. To a representation π of (1,1)(), we attach an integer () called the conductor of , which depends only on the -packet containing . A newform is a vector in which is essentially fixed by a congruence subgroup of level ()$. We show that our newforms are always test vectors for some standard Whittaker functionals, and, in doing so, we give various explicit formulae for newforms.

  14. Plasma waves and jets from moving conductors

    Science.gov (United States)

    Gralla, Samuel E.; Zimmerman, Peter

    2016-06-01

    We consider force-free plasma waves launched by the motion of conducting material through a magnetic field. We develop a spacetime-covariant formalism for perturbations of a uniform magnetic field and show how the transverse motion of a conducting fluid acts as a source. We show that fast-mode waves are sourced by the compressibility of the fluid, with incompressible fluids launching a pure-Alfvén outflow. Remarkably, this outflow can be written down in closed form for an arbitrary time-dependent, nonaxisymmetric incompressible flow. The instantaneous flow velocity is imprinted on the magnetic field and transmitted away at the speed of light, carrying detailed information about the conducting source at the time of emission. These results can be applied to transients in pulsar outflows and to jets from neutron stars orbiting in the magnetosphere of another compact object. We discuss jets from moving conductors in some detail.

  15. Recent progress in high-pressure studies on organic conductors

    Directory of Open Access Journals (Sweden)

    Syuma Yasuzuka and Keizo Murata

    2009-01-01

    Full Text Available Recent high-pressure studies of organic conductors and superconductors are reviewed. The discovery of the highest Tc superconductivity among organics under high pressure has triggered the further progress of the high-pressure research. Owing to this finding, various organic conductors with the strong electron correlation were investigated under high pressures. This review includes the pressure techniques using the cubic anvil apparatus, as well as high-pressure studies of the organic conductors up to 10 GPa showing extraordinary temperature and pressure dependent transport phenomena.

  16. Conductor development for the Superconducting Super Collider (SSC)

    International Nuclear Information System (INIS)

    This review investigates the developments in fine filamentary materials over the last three years and traces how the relations between the magnet requirements and property improvements have fashioned SSC conductor specifications. The review emphasizes factors that affect filament nonuniformity and the overall quality of the product. The elimination of proximity effect-induced coupling in SCC type conductors, by introducing small percentages of manganese into the copper between the filaments, is discussed. Modification of a Fermi kit has produced materials with improved critical current densities. The possibility of using this approach to make conductors for accelerator magnets is assessed

  17. Selecting the proper size for conductors and overcurrent protection devices

    International Nuclear Information System (INIS)

    This paper reports that most electricity-related industrial accidents result from an electrical system's inability to carry a continuous load without excessive heat buildup or to handle safely a short circuit or ground fault conditions when it occurs. Both of these potentially hazardous conditions can be minimized by properly sizing the conductors and the conductors' overcurrent protection device. In selecting the proper size for a conductor and a protective device it is important to understand the appropriate factors that may apply and how the conditions of application relate to the National Electrical Code (NEC) the electrical code that is legally applicable throughout most of the United States

  18. Emission factors and chemical characterisation of fine particulate emissions from modern and old residential biomass heating systems determined for typical load cycles; Emissionsfaktoren und chemische Charakterisierung von Feinstaubemissionen moderner und alter Biomasse-Kleinfeuerungen ueber typische Tageslastverlaeufe

    Energy Technology Data Exchange (ETDEWEB)

    Kelz, Joachim [BIOENERGY 2020+ GmbH, Graz (Austria); Brunner, Thomas; Obernberger, Ingwald [BIOENERGY 2020+ GmbH, Graz (Austria); Technische Universitaet Graz, Institut fuer Prozess- und Partikeltechnik, Graz (Austria); BIOS BIOENERGIESYSTEME GmbH, Graz (Austria)

    2012-12-15

    concerning gaseous and PM emissions of different old and modern biomass combustion systems over whole day operation cycles are now available. Derived from these data, correlations between burnout quality, particulate emissions as well as particle composition of the PM emissions can be deduced. (orig.) [German] Es ist allgemein bekannt, dass es signifikante Unterschiede bezueglich partikelfoermiger Emissionen von modernen und alten sowie automatisch und nicht automatisch geregelten Biomasse-Kleinfeuerungsanlagen gibt. Die Unterschiede beziehen sich einerseits auf die Hoehe der Partikelemission und andererseits auf deren chemische Zusammensetzung. Um Emissionsfaktoren fuer partikelfoermige Emissionen ueber typische realitaetsnahe Tageslastverlaeufe zu bestimmen und die Feinstaubemissionen chemisch zu charakterisieren, wurde ein Projekt an der BIOENERGY 2020+ GmbH, Graz, Oesterreich, in Kooperation mit dem Institut fuer Prozess- und Partikeltechnik, Technische Universitaet Graz, Oesterreich, initiiert. Fuenf moderne, dem aktuellen Stand der Technik entsprechende, Biomasse-Kleinfeuerungen sowie zwei Altanlagen, die den aktuellen Anlagenbestand widerspiegeln, wurden im Zuge von Testlaeufen an einem Teststand untersucht. Dabei wurden alle relevanten Betriebsparameter der Biomasse-Kleinfeuerungen sowie die im Zuge des Verbrennungsprozesses entstehenden gas- und partikelfoermigen Emissionen kontinuierlich gemessen und aufgezeichnet. Des Weiteren wurden Partikelemissionsproben gezogen und anschliessend chemisch analysiert. Fuer die Testlaeufe wurden typische Tageslastverlaeufe, die den Betrieb dieser Feuerungen in der Praxis abbilden, beruecksichtigt. Dabei wurde zwischen automatisch beschickten und automatisch geregelten Kesseln, manuell beschickten und automatisch geregelten Kesseln sowie manuell beschickten Naturzugoefen unterschieden. Die Ergebnisse zeigen einen deutlichen Zusammenhang zwischen den gasfoermigen Emissionen, die durch unvollstaendigen Gasphasenausbrand (CO- und org

  19. High-grade use of waste propane streams in the Dutch chemical industry. An exploratory study in the context of the Chemical Industry Roadmap; Hoogwaardig gebruik van reststromen propaan in de Nederlandse chemische industrie. Een verkenning binnen de Routekaart Chemie

    Energy Technology Data Exchange (ETDEWEB)

    De Buck, A.; Afman, M.R.; Croezen, H.J.; Van Lieshout, M.

    2012-09-15

    In the context of the Dutch chemical industry's Roadmap the industry is actively seeking concrete ways of improving the efficiency of its products and processes. One option is to make higher-grade use of current waste streams, as feedstocks for other products, for example. This study focuses on propane waste streams from the oil and gas processing industry. Today these are used partly as fuel (fuel gas) but there are no technical barriers to converting propane to propylene, which can then be used as a feedstock. Higher-grade use of this particular waste stream leads to CO2 emission reductions in the production chain. Given the high market price of propylene, such a move may also be economically attractive. The study focuses on the Rotterdam region, because propane suppliers and companies seeking propylene are in closest proximity there [Dutch] In het kader van de Routekaart Chemie is de chemische industrie actief op zoek naar concrete opties om in haar processen en producten de efficiency te verhogen. Een route is daarbij om reststromen hoogwaardiger te benutten en in te zetten als grondstof voor andere producten. Dit onderzoek richt zich op reststromen propaan uit de olie- en gasverwerkende industrie. Deze worden nu deels als brandstof (stookgas) ingezet maar technisch is het mogelijk propaan om te zetten in propeen, dat als grondstof voor de chemische industrie kan worden gebruikt. Door het hoogwaardiger benutten van deze reststroom wordt in de keten een reductie van CO2 gerealiseerd. Tegelijk kan het economisch interessant zijn, vanwege de hoge marktprijzen van propeen. De studie focust op de regio Rotterdam, omdat leveranciers van propaan en afnemers van propeen daar het meest dichtbij elkaar gevestigd zijn.

  20. Feasibility study to combine the evaluation of radiological and chemical-toxicological effects of old contaminated sites; Machbarkeitsstudie zur Verknuepfung der Bewertung radiologischer und chemisch-toxischer Wirkungen von Altlasten

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.; Proehl, G. [Gesellschaft fuer Strahlen- und Umweltforschung mbH Muenchen, Neuherberg (Germany). Inst. fuer Strahlenschutz; Schneider, K.; Voss, J.U. [FoBiG Forschungs- und Beratungsinstitut Gefahrstoffe GmbH, Freiburg im Breisgau (Germany)

    1997-08-01

    The uranium mining regions of the German Federal States Saxony, Thuringia and Saxony-Anhalt are contaminated by radionuclides and by chemical substances. For both, ionizing radiations and chemicals, concepts and models exists to assess possible health effects for the population living in such areas. However, these assessment models were developed independently for both kinds of contaminants. Therefore, the 9{sup th} Conference of the State Ministers for Environmental Protection have claimed that for the evaluation of contaminated sites the radiological and chemical contaminants should be integrated into a joint assessment. This feasibility study describes the state of the art of the concepts and models used for the evaluation of radiological and chemical contaminants. The similarities and differences of these evaluation methods are identified and discussed. Suggestions are made for an integrated assessment to standardize the evaluation of sites contaminated by radionuclides or chemicals. (orig.) [Deutsch] In den Gebieten des ehemaligen Uranbergbaus der Bundeslaender Sachsen, Thueringen und Sachsen-Anhalt treten neben den radioaktiven Kontaminationen auch andere Schadstoffe, insbesondere Schwermetalle, auf. Fuer ionisierende Strahlung und fuer chemische Noxen existieren unabhaengig voneinander entwickelte Bewertungssysteme zum Schutz vor Gesundheitsgefahren und Empfehlungen zum Umgang mit kontaminierten Standorten. Vor diesem Hintergrund forderte die 9. Umweltministerkonferenz - Ost am 17./18. Juni 1993 eine `Verknuepfung der radiologischen und konventionellen Altlastenbewertung`. Ob diese Verknuepfung moeglich ist und in welcher Weise diese vorgenommen werden kann, ist bisher nicht untersucht worden. Diese Machbarkeitsstudie unternimmt eine Bestandsaufnahme von Uebereinstimmungen und Unterschieden der beiden bestehenden Bewertungssysteme fuer Kontaminationen mit Radionukliden und mit chemisch-toxischen Stoffen und zeigt einen Weg auf zur Verinheitlichung der

  1. Kontrolle chemischer Reaktionen mit Elektronenstrahlung

    OpenAIRE

    Böhler, Esther

    2014-01-01

    Interaction between low-energy electrons and molecules can lead to dissociative electron attachment (DEA) or dissociative ionization (DI). In condensed matter, the resulting reactive fragments can attack adjacent molecules to yield larger products. In this thesis, reactions initiated by DEA to acetonitrile in condensed phase have been compared to the known gas phase fragmentation channels. Also, gas phase DEA experiments have been performed on chlorosilanes to study the effect of a variation ...

  2. Kool kan zonder chemische bestrijding

    NARCIS (Netherlands)

    Schans, van der D.A.

    2005-01-01

    Over volledig mechanische onkruidbestrijding in koolgewassen wordt vaak beweerd dat het te weersafhankelijk is en teveel capaciteit kost. Toch zijn er telers die erin slagen zonder herbiciden onkruid voldoende te bestrijden. Zoals René Verdonk in Wervershoof, die al jaren zonder onkruidbestrijdingsm

  3. High voltage switches having one or more floating conductor layers

    Science.gov (United States)

    Werne, Roger W.; Sampayan, Stephen; Harris, John Richardson

    2015-11-24

    This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

  4. Effect of joint quality on conductor short sample performance

    International Nuclear Information System (INIS)

    Full size conductor short samples for the International Thermonuclear Experimental Reactor (ITER) are composed of two straight bars connected together at one end, and to the facility current leads at the other ends. The quality of these electrical connections was early suspected to play a role in the measurement of the conductor performance, which has been confirmed by recent test results. In order to investigate this phenomenon, CEA developed an experimental program, to study the effect of well calibrated joint defaults on sub-size NbTi conductor performances. Two types of NbTi strands associated with two different cable void fractions were used in order to vary the interstrand resistances. Experimental results clearly show that joint defaults degrade measured conductor critical currents, except when sufficiently low interstrand resistances allow a possible current redistribution among strands. Analysis of Hall probe signals show evidence of current redistribution among sub-cables during the tests. (authors)

  5. A microstructure continuum approach to electromagneto-elastic conductors

    Science.gov (United States)

    Romeo, Maurizio

    2016-06-01

    A micromorphic continuum model of a deformable electromagnetic conductor is established introducing microdensities of bound and free charges. The conductive part of electric current consists of contributions due to free charges and microdeformation. Beside the conservation of charge, we derive suitable evolution equations for electric multipoles which are exploited to obtain the macroscopic form of Maxwell's equations. A constitutive model for electromagneto-elastic conductors is considered which allows for a natural characterization of perfect conductors independently on the form of the constitutive equation for the conduction current. A generalized Ohm's law is also derived for not ideal conductors which accounts for relaxation effects. The consequences of the linearized Ohm's law on the classic magnetic transport equation are shown.

  6. Study on detinning process of a reflow conductor roll

    Institute of Scientific and Technical Information of China (English)

    FU Hanguang; DAI Mingshan; FU Hanfeng

    2005-01-01

    Adhering tin is the main reason of a reflow conductor roll which works in an electroplating tin line (ETL). A detinning agent whose main composition is NaOH and KOH and assistant composition is Na2PbO2 or K2PbO2 and NaNO3 or NaNO2 has excellent detinning effects when the temperature of detinning solution is 40-80℃ and the temperature of the reflow conductor roll reaches 40-70℃. After the adhering tin layer of the reflow conductor roll is removed, the roughness of the reflow conductor roll can resume to 4.0 μm, its service life increases by 80%, and the repairing cost decreases by 90%.

  7. Casimir Free Energy at High Temperatures: Grounded vs Isolated Conductors

    CERN Document Server

    Fosco, C D; Mazzitelli, F D

    2016-01-01

    We evaluate the difference between the Casimir free energies corresponding to either grounded or isolated perfect conductors, at high temperatures. We show that a general and simple expression for that difference can be given, in terms of the electrostatic capacitance matrix for the system of conductors. For the case of close conductors, we provide approximate expressions for that difference, by evaluating the capacitance matrix using the proximity force approximation. Since the high-temperature limit for the Casimir free energy for a medium described by a frequency-dependent conductivity diverging at zero frequency coincides with that of an isolated conductor, our results may shed light on the corrections to the Casimir force in the presence of real materials.

  8. Tilt stability of rotating current rings with passive conductors

    International Nuclear Information System (INIS)

    We study the combined effects of rotation and resistive passive conductors on the stability of a rigid current in an external magnetic field. We present numerical and approximate analytical solutions to the equations of motion, which show that the ring is always tilt unstable on the resistive decay timescale of the conductors, although rotation and eddy currents may stabilize it over short times. Possible applications of our model include spheromaks which rotate or which are encircled by energetic particle rings

  9. Solid state proton conductors properties and applications in fuel cells

    CERN Document Server

    Knauth, Philippe

    2012-01-01

    Proton conduction can be found in many different solid materials, from organic polymers at room temperature to inorganic oxides at high temperature. Solid state proton conductors are of central interest for many technological innovations, including hydrogen and humidity sensors, membranes for water electrolyzers and, most importantly, for high-efficiency electrochemical energy conversion in fuel cells. Focusing on fundamentals and physico-chemical properties of solid state proton conductors, topics covered include: Morphology and Structure of Solid Acids Diffusion in Soli

  10. Spatial Analysis of Thermal Aging of Overhead Transmission Conductors

    Czech Academy of Sciences Publication Activity Database

    Musílek, P.; Heckenbergerová, Jana; Bhuiyan, M.M.I.

    2012-01-01

    Roč. 27, č. 3 (2012), s. 1196-1204. ISSN 0885-8977 Grant ostatní: GA AV ČR(CZ) M100300904 Source of funding: V - iné verejné zdroje Keywords : aluminium conductor steel reinforced (ACSR) conductor * hot spot * loss of tensile strength * numerical weather prediction * power transmission lines * thermal aging Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use Impact factor: 1.519, year: 2012

  11. Tilt stability of rotating current rings with passive conductors

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, E.G.; Pomphrey, N.

    1984-12-01

    We study the combined effects of rotation and resistive passive conductors on the stability of a rigid current in an external magnetic field. We present numerical and approximate analytical solutions to the equations of motion, which show that the ring is always tilt unstable on the resistive decay timescale of the conductors, although rotation and eddy currents may stabilize it over short times. Possible applications of our model include spheromaks which rotate or which are encircled by energetic particle rings.

  12. Design, development, fabrication and testing of high temperature Flat Conductor Cable (FCC)

    Science.gov (United States)

    Rigling, W. S.

    1974-01-01

    The results are presented of a development program for a flat, 25-conductor signal cable and a flat, 3-conductor power cable. Flat cables employ conductors made of strips or flattened round copper conductors insulated with polyimide films. It is shown that conductor thickness ranges from 0.003 to 0.010 inch, and begins to soften and loose mechanical strength at temperatures above 200 C.

  13. Internally heated convection beneath a poor conductor

    CERN Document Server

    Goluskin, David

    2016-01-01

    We consider convection in an internally heated layer of fluid that is bounded below by a perfect insulator and above by a poor conductor. The poorly conducting boundary is modelled by a fixed heat flux. Using solely analytical methods, we find linear and energy stability thresholds for the static state, and we construct a lower bound on the mean temperature that applies to all flows. The linear stability analysis yields a Rayleigh number above which the static state is linearly unstable ($R_L$), and the energy analysis yields a Rayleigh number below which it is globally stable ($R_E$). For various boundary conditions on the velocity, exact expressions for $R_L$ and $R_E$ are found using long-wavelength asymptotics. Each $R_E$ is strictly smaller than the corresponding $R_L$ but is within 1%. The lower bound on the mean temperature is proven for no-slip velocity boundary conditions using the background method. The bound guarantees that the mean temperature of the fluid, relative to that of the top boundary, gr...

  14. Transport AC losses in YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Majoros, M [Ohio State University, Columbus, OH 43210 (United States); Ye, L [IRC in Superconductivity, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Velichko, A V [IRC in Superconductivity, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Coombs, T A [IRC in Superconductivity, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Sumption, M D [Ohio State University, Columbus, OH 43210 (United States); Collings, E W [Ohio State University, Columbus, OH 43210 (United States)

    2007-09-15

    Transport AC loss measurements have been made on YBCO-coated conductors prepared on two different substrate templates-RABiTS (rolling-assisted biaxially textured substrate) and IBAD (ion-beam-assisted deposition). RABiTS samples show higher losses compared with the theoretical values obtained from the critical state model, with constant critical current density, at currents lower than the critical current. An origin of this extra AC loss was demonstrated experimentally by comparison of the AC loss of two samples with different I-V curves. Despite a difference in I-V curves and in the critical currents, their measured losses, as well as the normalized losses, were practically the same. However, the functional dependence of the losses was affected by the ferromagnetic substrate. An influence of the presence of a ferromagnetic substrate on transport AC losses in YBCO film was calculated numerically by the finite element method. The presence of a ferromagnetic substrate increases transport AC losses in YBCO films depending on its relative magnetic permeability. The two loss contributions-transport AC loss in YBCO films and ferromagnetic loss in the substrate-cannot be considered as mutually independent.

  15. Conductor gestures influence evaluations of ensemble performance

    Directory of Open Access Journals (Sweden)

    Steven eMorrison

    2014-07-01

    Full Text Available Previous research has found that listener evaluations of ensemble performances vary depending on the expressivity of the conductor’s gestures, even when performances are otherwise identical. It was the purpose of the present study to test whether this effect of visual information was evident in the evaluation of specific aspects of ensemble performance, articulation and dynamics. We constructed a set of 32 music performances that combined auditory and visual information and were designed to feature a high degree of contrast along one of two target characteristics: articulation and dynamics. We paired each of four music excerpts recorded by a chamber ensemble in both a high- and low-contrast condition with video of four conductors demonstrating high- and low-contrast gesture specifically appropriate to either articulation or dynamics. Using one of two equivalent test forms, college music majors and nonmajors (N = 285 viewed sixteen 30-second performances and evaluated the quality of the ensemble’s articulation, dynamics, technique and tempo along with overall expressivity. Results showed significantly higher evaluations for performances featuring high rather than low conducting expressivity regardless of the ensemble’s performance quality. Evaluations for both articulation and dynamics were strongly and positively correlated with evaluations of overall ensemble expressivity.

  16. Synergistic, ultrafast mass storage and removal in artificial mixed conductors.

    Science.gov (United States)

    Chen, Chia-Chin; Fu, Lijun; Maier, Joachim

    2016-08-11

    Mixed conductors-single phases that conduct electronically and ionically-enable stoichiometric variations in a material and, therefore, mass storage and redistribution, for example, in battery electrodes. We have considered how such properties may be achieved synergistically in solid two-phase systems, forming artificial mixed conductors. Previously investigated composites suffered from poor kinetics and did not allow for a clear determination of such stoichiometric variations. Here we show, using electrochemical and chemical methods, that a melt-processed composite of the 'super-ionic' conductor RbAg4I5 and the electronic conductor graphite exhibits both a remarkable silver excess and a silver deficiency, similar to those found in single-phase mixed conductors, even though such behaviour is not possible in the individual phases. Furthermore, the kinetics of silver uptake and release is very fast. Evaluating the upper limit set by interfacial ambipolar diffusion reveals chemical diffusion coefficients that are even higher than those achieved for sodium chloride in bulk liquid water. These results could potentially stimulate systematic research into powerful, even mesoscopic, artificial mixed conductors. PMID:27510217

  17. Safety analysis of the GEM Detector Magnet conductor

    International Nuclear Information System (INIS)

    The safety of the GEM Detector Magnet is analyzed using a computational model to determine current sharing between the cabled conductor and the external aluminum stabilizer. The model includes inductive and transverse conductive effects due to the geometries of the coil and the conductor. A conservative analysis indicates a peak conductor hotspot temperature of ∼ 50 K at two seconds after the initiation of quench. After this time, additional heating is limited because most of the current in the normal zone region is carried by the aluminum stabilizer and an external protection circuit should have begun to diminish the total current. The analysis shows that conductor safety requires adequate transverse conductivity between the cable and the aluminum stabilizer. The calculated transverse conductance of the GEM conductor, 1 x 107 mho/m, is at least 100 times greater than the minimum value necessary to limit the hotspot temperature to ∼ 50 K after two seconds. This report describes the results of calculations based on a realistic assumption of GEM conductor performance during a quench

  18. Trial manufacture of x-band accelerator disks

    International Nuclear Information System (INIS)

    In the X-band accelerator scheme of future linear colliders with normal conductor technology, major issue was the mass production of accelerator structures and microwave transmission devices with ultrahigh precision. Hitachi Ltd. has a technology of ultrahigh precision machining of soft metals, and made trial manufacturing of accelerator disks with ultrahigh precision during half a year from the spring of 2004 based on the blueprint prepared by KEK. The results of this trial are reported. (K.Y.)

  19. ab initio Studies on Molecular Conductor (BEDSe-TTF)2[Fe(CN)5NO

    Institute of Scientific and Technical Information of China (English)

    YAO Kai-Lun; TU Hai-Bo; WANG Wei-Zhong

    2001-01-01

    In this paper the ab initio study using pseudopotential plane wave method with the local spin density functional approximation is presented for the molecular conductor (BEDSe-TTF)2[Fe(CN)5NO]. The mean electronic density distributions are obtained, and we find that the extended π orbital of the selenium does not affect the properties of material as assumed in other papers and the "side-by-side" type S...S interaction is the primary interaction between donors. From band structure calculations we analyze the influence of the NO groups on the electronic structure and magnetic properties of molecule. It is shown that the itinerant electrons important to electronic properties in these types of hybrids are delocalized electrons contributed by NO groups, instead of by the 3d electrons of Fe. Additionally, we have found that the localized magnetic moment is also contributed by the NO groups in this molecular conductor. From total energy calculations the molecular structure with the lowest energy is found due to the interaction between split spins, and the particular positions of the NO groups are obtained.

  20. Copper and Transparent-Conductor Reflectarray Elements on Thin-Film Solar Cell Panels

    CERN Document Server

    Dreyer, Philippe; Nicolay, Sylvain; Ballif, Christophe; Perruisseau-Carrier, Julien

    2013-01-01

    This work addresses the integration of reflectarray antennas (RA) on thin film Solar Cell (SC) panels, as a mean to save real estate, weight, or cost in platforms such as satellites or transportable autonomous antenna systems. Our goal is to design a good RA unit cell in terms of phase response and bandwidth, while simultaneously achieving high optical transparency and low microwave loss, to preserve good SC and RA energy efficiencies, respectively. Since there is a trade-off between the optical transparency and microwave surface conductivity of a conductor, here both standard copper and transparent conductors are considered. The results obtained at the unit cell level demonstrates the feasibility of integrating RA on a thin-film SC, preserving for the first time good performance in terms of both SC and RA efficiency. For instance, measurement at X-band demonstrate families of cells providing a phase range larger than 270{\\deg} with average microwave loss of -2.45dB (resp. -0.25dB) and average optical transpa...

  1. Design and Simulation of Edge-Coupled Stripline Band Pass Filter for U band

    Directory of Open Access Journals (Sweden)

    Pawan Shakdwipee

    2013-08-01

    Full Text Available In this paper, a band pass filter structure using Ansoft designer software and Matlab software simulation tool are presented. The filter is operated at U Band range in higher order 50 GHz edge-coupled Stripline band pass filter for different microwave application. For the proposed work we consider simulation using Roger R03203 substrate with dielectric constant of 3.02, Conductor Thickness 0.035 mm and Substrate Height 0.787 mm. This filter is design at a center frequency of 50 GHz with 8 GHz bandwidth. Simulation results show that the filter operation is optimum and best in this range and results show good performance and agree well with the high frequency EM full wave simulation. In this paper, band pass filter development with the assistance of the Richards-Kuroda Transformation method, is used. Moreover, measured S parameters denote the center frequency is also strongly influenced by the variation of Roger's material's dielectric constants. By analyzing the characteristics at center frequency of the filter, both theoretical and simulated data are accumulated for broadening application filed. The band pass filter exhibits advantages of small size and high reliability compared to conventional planar filter structure, which makes the band pass filter suitable for U Band communicational application. This filter shows attractive characteristics for BPF applications.

  2. Design of force-cooled conductors for large fusion magnets

    Energy Technology Data Exchange (ETDEWEB)

    Dresner, L.; Lue, J.W.

    1977-01-01

    Conductors cooled by supercritical helium in forced convection are under active consideration for large toroidal fusion magnets. One of the central problems in designing such force cooled conductors is to maintain an adequate stability margin while keeping the pumping power tolerably low. A method has been developed for minimizing the pumping power for fixed stability by optimally choosing the matrix-to-superconductor and the metal-to-helium ratios. Such optimized conductors reduce pumping power requirements for fusion size magnets to acceptable limits. Furthermore, the mass flow and hence pumping losses can be varied through a magnet according to the local magnetic field and magnitude of desired stability margin. Force cooled conductors give flexibility in operation, permitting, for example, higher fields to be obtained than originally intended by lowering the bath temperature or increasing the pumping power or both. This flexibility is only available if the pumping power is low to begin with. Scaling laws for the pumping requirement and stability margin as functions of operating current density, number of strands and such physical parameters as stabilizer resistivity and critical current density, have been proved. Numerical examples will be given for design of conductors intended for use in large toroidal fusion magnet systems.

  3. Procurement of Nb3Sn superconducting conductors in ITER

    International Nuclear Information System (INIS)

    Superconducting strands are applied to Toroidal Field (TF) coil, Poloidal Field (PF) coil and Centre Solenoid (CS) in ITER. Japanese share of TF conductor is 25% and that of CS conductor is 100%. The conductor of TF coil contains 900 Nb3Sn superconducting strands and 522 copper wires. As described in the length of superconducting strand, the length of Japanese share is 23,000km. In order to generate the magnetic field of which maximum value is 11.8T, 68kA of current is sent through the conductor under the rated operation. Although the critical current must be high, the high critical current tends to make the hysteresis loss rise at the same time. The hysteresis loss must be low because that is the heat generation under a fluctuating magnetic field. The strands which satisfy these performances compatibly had been developed. In advance of the other parties, the production of strands for TF coil started in 2008. To date, 3,400km long strands have been fabricated. Some of them are going to be cabled soon. The jacketing facility of TF conductor is being newly built. The building is almost completed. The procurement of strands for TF coil is underway. (author)

  4. Design of force-cooled conductors for large fusion magnets

    International Nuclear Information System (INIS)

    Conductors cooled by supercritical helium in forced convection are under active consideration for large toroidal fusion magnets. One of the central problems in designing such force cooled conductors is to maintain an adequate stability margin while keeping the pumping power tolerably low. A method has been developed for minimizing the pumping power for fixed stability by optimally choosing the matrix-to-superconductor and the metal-to-helium ratios. Such optimized conductors reduce pumping power requirements for fusion size magnets to acceptable limits. Furthermore, the mass flow and hence pumping losses can be varied through a magnet according to the local magnetic field and magnitude of desired stability margin. Force cooled conductors give flexibility in operation, permitting, for example, higher fields to be obtained than originally intended by lowering the bath temperature or increasing the pumping power or both. This flexibility is only available if the pumping power is low to begin with. Scaling laws for the pumping requirement and stability margin as functions of operating current density, number of strands and such physical parameters as stabilizer resistivity and critical current density, have been proved. Numerical examples will be given for design of conductors intended for use in large toroidal fusion magnet systems

  5. Fine filament NbTi and Nb3Sn conductors

    International Nuclear Information System (INIS)

    Fine filament conductors are needed for applications requiring low hysteresis losses and/or low magnetization in small fields in order to reduce field distortions. Examples are accelerator magnets (dipoles and quadrupoles) and magnets for TOKAMAK nuclear fusion devices. The main task is to achieve low magnetization especially at low fields while maintaining high critical current density jC at high fields. The relevant parameters are the width 2ΔM of the magnetization curve and the area of the M-H-curve during a field cycle, respectively. In this work, NbTi and Nb3Sn fine filament conductors were produced on a large scale and characterized with respect to transport critical current density and magnetization behavior. In NbTi jc values of about 3000 A/mm2 at 5 T and 4.2 K were achieved in 5 μm filament diameter single stack type conductors. Deterioration of the order of 15 to 20 % was observed when using double stack techniques and/or when going to 2.5 μm type conductors. Possible reasons were identified and work is in progress to improve jc further. At external fields smaller than 100 mT proximity effect induced excess magnetization was observed in Cu matrix conductors and its dependence on filament spacing, twist pitch, field sweep rate, and temperature was measured. The effect is significant, but plays a role only in applications where this low field regime is relevant

  6. Quantum Optics Theory of Electronic Noise in Coherent Conductors.

    Science.gov (United States)

    Grimsmo, Arne L; Qassemi, Farzad; Reulet, Bertrand; Blais, Alexandre

    2016-01-29

    We consider the electromagnetic field generated by a coherent conductor in which electron transport is described quantum mechanically. We obtain an input-output relation linking the quantum current in the conductor to the measured electromagnetic field. This allows us to compute the outcome of measurements on the field in terms of the statistical properties of the current. We moreover show how under ac bias the conductor acts as a tunable medium for the field, allowing for the generation of single- and two-mode squeezing through fermionic reservoir engineering. These results explain the recently observed squeezing using normal tunnel junctions [G. Gasse et al., Phys. Rev. Lett. 111, 136601 (2013); J.-C. Forgues et al., Phys. Rev. Lett. 114, 130403 (2015)]. PMID:26871330

  7. Mobility propagation and dynamic facilitation in superionic conductors

    Energy Technology Data Exchange (ETDEWEB)

    Annamareddy, Ajay, E-mail: vkannama@ncsu.edu; Eapen, Jacob, E-mail: jacob.eapen@ncsu.edu [Department of Nuclear Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2015-11-21

    In an earlier work [V. A. Annamareddy et al., Phys. Rev. E 89, 010301(R) (2014)], we showed the manifestation of dynamical heterogeneity (DH)—the presence of clustered mobile and immobile regions—in UO{sub 2}, a model type II superionic conductor. In the current work, we demonstrate the mechanism of dynamic facilitation (DF) in two superionic conductors (CaF{sub 2} and UO{sub 2}) using atomistic simulations. Using the mobility transfer function, DF is shown to vary non-monotonically with temperature with the intensity of DF peaking at temperatures close to the superionic transition temperature (T{sub λ}). Both the metrics quantifying DH and DF show remarkable correspondence implying that DF, in the framework of kinematically constrained models, underpins the heterogeneous dynamics in type II superionic conductors.

  8. Characterization of textile electrodes and conductors using standardized measurement setups

    International Nuclear Information System (INIS)

    Textile electrodes and conductors are being developed and used in different monitoring scenarios, such as ECG or bioimpedance spectroscopy measurements. Compared to standard materials, conductive textile materials offer improved wearing comfort and enable long-term measurements. Unfortunately, the development and investigation of such materials often suffers from the non-reproducibility of the test scenarios. For example, the materials are generally tested on human skin which is difficult since the properties of human skin differ for each person and can change within hours. This study presents two test setups which offer reproducible measurement procedures for the systematic analysis of textile electrodes and conductors. The electrode test setup was designed with a special skin dummy which allows investigation of not only the electrical properties of textile electrodes but also the contact behavior between electrode and skin. Using both test setups, eight textile electrodes and five textile conductors were analyzed and compared

  9. Nb3Sn conductor development for the ITER magnets

    International Nuclear Information System (INIS)

    The ITER magnet system consists of Toroidal Field (TF) coils, Poloidal Field (PF) coils, the Central Solenoid (CS) and error field correction coils (CC). The conductors for the coils are Nb3Sn or NbTi cable in conduit type, forced flow cooled with supercritical helium having a maximum operating current in the range 40-60 kA. To qualify the Nb3Sn conductor, two large model coils (energy up to 640 MJ) are being wound by the Home Teams of the Parties to the ITER EDA Agreement. A total of 24 t of strand has been completed for the CS model coil and 4 t for the TF model coil, and fabricated into 7 km of conductor in unit lengths up to 210 m, by an international collaboration involving 12 companies in Europe, Japan, Russia and the USA

  10. Quantum Optics Theory of Electronic Noise in Coherent Conductors

    Science.gov (United States)

    Grimsmo, Arne L.; Qassemi, Farzad; Reulet, Bertrand; Blais, Alexandre

    2016-01-01

    We consider the electromagnetic field generated by a coherent conductor in which electron transport is described quantum mechanically. We obtain an input-output relation linking the quantum current in the conductor to the measured electromagnetic field. This allows us to compute the outcome of measurements on the field in terms of the statistical properties of the current. We moreover show how under ac bias the conductor acts as a tunable medium for the field, allowing for the generation of single- and two-mode squeezing through fermionic reservoir engineering. These results explain the recently observed squeezing using normal tunnel junctions [G. Gasse et al., Phys. Rev. Lett. 111, 136601 (2013); J.-C. Forgues et al., Phys. Rev. Lett. 114, 130403 (2015)].

  11. Photonic crystals composed of virtual pillars with magnetic walls: Photonic band gaps and double Dirac cones

    Science.gov (United States)

    Kim, Seong-Han; Kim, Soeun; Kee, Chul-Sik

    2016-08-01

    Photonic crystals composed of virtual pillars with magnetic walls are proposed. A virtual pillar with a magnetic wall can be created inside a parallel perfect electric conductor plate waveguide by introducing a circular perfect magnetic conductor patch in the upper perfect electric conductor plate of the waveguide. The virtual pillar mimics a perfect magnetic conductor pillar with a radius less than that of the circular patch because electromagnetic waves can slightly penetrate the wall. Furthermore, the photonic band structures of a triangular photonic crystal composed of virtual pillars for the transverse electromagnetic modes of the waveguide are investigated. They are very similar to those of a triangular photonic crystal composed of infinitely long perfect electric conductor cylinders for transverse magnetic modes. The similarity between the two different photonic crystals is well understood by the boundary conditions of perfect electric and magnetic conductor surfaces. A double Dirac cone at the center of the Brillouin zone is observed and thus the virtual pillar triangular photonic crystal can act a zero-refractive-index material at the Dirac point frequency.

  12. Use of polymer conductors for welding thermoplastic materials

    International Nuclear Information System (INIS)

    Although some polymer conductors of electricity (ex. Polyanilines) are materials known for more than 100 years, only recently have the interesting chemical, electrical and optic properties of their insulating and conducting forms been recognized. Advances made in the chemistry of polymer conductors have also led to improvements in processing them. This work studies a practical application of these materials: the use of polymer conductors for the remote welding of insulating thermoplastic polymers, using energy from microwaves for the local heating of the union. Many thermoplastics (for ex. Polyethylene) do not absorb, or absorb very little, energy from microwaves. Different conductor materials (conductor polymers, carbon nanotubes), however, heavily absorb energy from microwaves with the resulting heating. In this way the welding zone can be heated without affecting the rest of the piece. Conductor polymers (polyanilines) were synthesized chemically and they were characterized by infrared spectroscopy. Polyanilines and other materials (carbon nanotubes) were also modified by reaction with diazone salts. Tests were carried out using different types of coupling: in powder, with material in suspension with wax, with material in suspension with Vaseline, with painted soluble material and with in-situ synthesized polymer on both surfaces to be joined. Different exposure times were tested in a 700 W microwave oven; the 10 mm bars made with different thermoplastic materials, particularly high density polyethylene (HDPE) and polypropylene (PP), were welded. These welded unions were then mechanically tested. The tests on the mechanical properties of the unions yielded an interesting repetition of results when samples welded by microwaves were examined under the same conditions. It was shown that splices can be achieved with reasonably acceptable mechanical resistance in a reduced processing time (CW)

  13. Engineered microstructures and transport properties in YBCO coated conductors.

    Energy Technology Data Exchange (ETDEWEB)

    Holesinger, T. G. (Terry G.); Gibbons, B. J. (Brady J.); Coulter, J. Y. (James Y.); Foltyn, S. R. (Stephen R.); Arendt, P. N. (Paul N.)

    2001-01-01

    Each process used to deposit or make the bi-axially textured template, buffer layer(s), and the superconductor in a coated conductor creates interfaces along which defects or interfacial reactions may result. These defects can be additive and propagate through the entire film structure to affect the growth and properties of the superconducting film. Defects within the films and their corresponding transport properties have been correlated with the differences in the thickness of the underlying buffer layer material. This knowledge can be used to control and engineer the structure of the coated conductor to maximize critical current densities.

  14. In the search of new electrocaloric materials: Fast ion conductors

    Directory of Open Access Journals (Sweden)

    Claudio Cazorla

    2015-01-01

    Full Text Available We analyse the effects of applying an electric field on the critical temperature at which superionicity appears in archetypal fast ion conductor CaF2, by means of molecular dynamics simulations. We find that the onset of superionicity can be reduced by about 100 K when relatively small electric fields of ∼50 KV cm−1 are applied. Under large enough electric fields, however, ionic conductivity is depleted. The normal to superionic phase transition is characterised by a large increase of entropy, thereby sizeable electrocaloric effects can be realised in fast ion conductors that are promising for solid-state cooling applications.

  15. Organic conductors as novel ``molecular rulers`` for advanced manufacturing processes

    Energy Technology Data Exchange (ETDEWEB)

    Williams, J.M.

    1995-12-31

    Future advanced manufacturing equipment used in high technology programs will require ultra-high precision and associated machining tool operations that require placement accuracy of {approximately} 1--100 nm (1 nm = 10 {angstrom}). There is consensus among engineers that this equipment will be based on STM (Scanning Tunneling Microscope) technology. All such STM-based ``drivers`` must contain a metrology system that requires absolute length standards referenced to atomic spacings for calibration. Properly designed organic conductor substrate crystals have the potential to be molecular rulers for STM-based advanced manufacturing equipment. The major challenges in future organic conductor research aimed at STM metrology application are listed.

  16. Sub-electron Charge Relaxation via 2D Hopping Conductors

    OpenAIRE

    Kinkhabwala, Yusuf A.; Likharev, Konstantin K.

    2005-01-01

    We have extended Monte Carlo simulations of hopping transport in completely disordered 2D conductors to the process of external charge relaxation. In this situation, a conductor of area $L \\times W$ shunts an external capacitor $C$ with initial charge $Q_i$. At low temperatures, the charge relaxation process stops at some "residual" charge value corresponding to the effective threshold of the Coulomb blockade of hopping. We have calculated the r.m.s$.$ value $Q_R$ of the residual charge for a...

  17. Improvement of SOFC electrodes using mixed ionic-electronic conductors

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzaki, Y.; Hishinuma, M. [Tokyo Gas Co., Ltd. (Japan)

    1996-12-31

    Since the electrode reaction of SOFC is limited to the proximity of a triple phase boundary (TPB), the local current density at the electrode and electrolyte interface is larger than mean current density, which causes large ohmic and electrode polarization. This paper describes an application of mixed ionic-electronic conductors to reduce such polarization by means of (1) enhancing ionic conductivity of the electrolyte surface layer by coating a high ionic conductors, and (2) reducing the local current density by increasing the electrochemically active sites.

  18. Substrate Integrated Waveguides Structures using Frequency Selective Surfaces operating in Stop-Band (SBFSS-SIW)

    OpenAIRE

    Esparza López, Nuria; Alcón García, Pablo; Herrán Ontañón, Luis Fernando; Las Heras Andrés, Fernando Luis

    2016-01-01

    A novel Substrate Integrated Waveguide (SIW) is proposed using Frequency Selective Surfaces (FSS) operating in Stop- Band (SBFSS-SIW) as metal conductor plates. These structures preserve the propagation properties and the dimensions of the conventional SIW, and have periodic isolated pads that could allow the direct integration of biased active and passive devices on the SIW surface. A set of SBFSS-SIW for X-band have been designed, simulated and experimentally measured to demonstrat...

  19. Diffusion of magnetic fields into conductors of non-uniform resistivity

    International Nuclear Information System (INIS)

    Solutions are obtained for the spatial variation of electrical resistivity of cylindrical and rectangular conductors such that the magnetic field external to the conductor maintains a constant spatial variation as the magnetic field diffuses into the conductor. Practical implementations of the ideal solution are described

  20. Biological and chemical development of mining lakes. Status report 1998/1999. Data acquisition, methods, trends; Biologische und chemische Entwicklung von Bergbaurestseen. Statusbericht 1998/1999. Bestandsaufnahme, Methoden und Entwicklungen

    Energy Technology Data Exchange (ETDEWEB)

    Friese, K.; Tuempling, W. von (eds.)

    2000-07-01

    Acidification of mining lakes in central Germany and the Lausitz was investigated for three aspects: 1.) biological dynamics and material effects on plancton abundance and variety; 2.) Chemical and microbiological interactions between sediments influenced by mining (authochthone, allochthone) and water phase 3. 3.) Limnological and hydrochemical development of water systems in abandoned mining areas with a view to environmental quality and/or utilisation. The following objects were investigated. a) Goitsche open-cast mine (Bitterfeld district); b) Lake 111 (Koyne/Pllessa district), - Lakes 107, 117 (Koyne/Plessa district), Lake b (Schlabendorf-Nord district). [German] Kernproblem in den Braunkohlengebieten der neuen Bundeslaender ist die Versauerung von Bergbauseen. Die Bearbeitung des Verbundprojektes konzentriert sich in den Bergbaufolgelandschaften der Regionen Mitteldeutschland und Lausitz auf bergbaulich gestoerte und in Veraenderung befindliche Oberflaechenwasser-Systeme. Arbeitziele sind 1.) die Vertiefung der Kenntnisse zur biologischen Dynamik und zum stofflichen Einfluss auf die Diversitaet und Abundanz von Plankton in sauren Bergbauseen 2) Untersuchungen zu spezifischen Wechselwirkungen (chemisch, mikrobiologisch) zwischen bergbaulich beeinflussten Sedimenten (autochthon, allochthon) und der Wasserphase 3. Betrachtungen der limnologischen und hydrochemischen Entwicklung der Wassersysteme in Bergbaufolgelandschaften hinsichtlich Umweltqualitaetszielen und/oder Nutzungszielen. Im Rahmen des Verbundprojektes werden von den Sektionen Gewaesserforschung, Hydrogeologie, Analytik, Bodenforschung und Umweltmikrobiologie in Mitteldeutschland und der Lausitz folgende Objekte bearbeitet: a) Tagebaukomplex Goitsche (Bitterfelder Revier) und b) Restloch 111 (Revier Koyne/Plessa), - Restloch 107, 117 (Revier Koyne/Plessa), - Restloch B (Revier Schlabendorf-Nord). (orig.)

  1. Attentional flexibility and memory capacity in conductors and pianists.

    Science.gov (United States)

    Wöllner, Clemens; Halpern, Andrea R

    2016-01-01

    Individuals with high working memory (WM) capacity also tend to have better selective and divided attention. Although both capacities are essential for skilled performance in many areas, evidence for potential training and expertise effects is scarce. We investigated the attentional flexibility of musical conductors by comparing them to equivalently trained pianists. Conductors must focus their attention both on individual instruments and on larger sections of different instruments. We studied students and professionals in both domains to assess the contributions of age and training to these skills. Participants completed WM span tests for auditory and visual (notated) pitches and timing durations, as well as long-term memory tests. In three dichotic attention tasks, they were asked to detect small pitch and timing deviations from two melodic streams presented in baseline (separate streams), selective-attention (concentrating on only one stream), and divided-attention (concentrating on targets in both streams simultaneously) conditions. Conductors were better than pianists in detecting timing deviations in divided attention, and experts detected more targets than students. We found no group differences for WM capacity or for pitch deviations in the attention tasks, even after controlling for the older age of the experts. Musicians' WM spans across multimodal conditions were positively related to selective and divided attention. High-WM participants also had shorter reaction times in selective attention. Taken together, conductors showed higher attentional flexibility in successfully switching between different foci of attention. PMID:26404532

  2. Exploring a Metamorphosis: Identity Formation for an Emerging Conductor

    Science.gov (United States)

    Ponchione, Cayenna

    2013-01-01

    Exploring the manner in which professional identity formation in emerging conductors is entangled with the cultural context of orchestras, I focus on the amorphous evolution from a student identity to that of a professional, illuminating some underlying social conditions of the ever-elusive profession of conducting. Prevailing assumptions about…

  3. Aharonov-Bohm oscillations in singly connected disordered conductors.

    Science.gov (United States)

    Aleiner, I L; Andreev, A V; Vinokur, V

    2015-02-20

    We show that the transport and thermodynamic properties of a singly connected disordered conductor exhibit quantum Aharonov-Bohm oscillations as a function of the total magnetic flux through the sample. The oscillations are associated with the interference contribution from a special class of electron trajectories confined to the surface of the sample. PMID:25763968

  4. Spectral magnetotelluric impedances for an anisotropic layered conductor

    Czech Academy of Sciences Publication Activity Database

    Pek, Josef

    2002-01-01

    Roč. 50, č. 4 (2002), s. 619-643. ISSN 0001-5725 R&D Projects: GA ČR GA205/99/0917; GA MŠk ME 185 Institutional research plan: CEZ:AV0Z3012916 Keywords : magnetotelluric impedance * anisotropic conductor * electromagnetic induction Subject RIV: DE - Earth Magnetism, Geodesy, Geography

  5. Comparison of two ICCS conductors for MHD application

    International Nuclear Information System (INIS)

    Two subscale internally cooled, cabled superconductors have been examined as candidates for use in a retrofit MHD topping cycle magnet. One of these was a 3 x 3 x 3 cable in which all the strands were multifilamentary NbTi stabilized with copper. The other was a 3 x 3 x 3 cable in which two strands in each of the nine triplets was OFHC copper and one was multifilamentary NbTi. The overall copper-to-superconductor ratio for each of the two 27-strand cables was approximately the same. The two conductors were cowound onto a grooved mandrel in such a way that they could be tested alternately. Each sample was instrumented with a heater at the center of the conductor length, and with a pressure transducer, four pairs of voltage tape and one iron-doped gold/constantan thermocouple. Performance tests of the conductors were made at 6, 7 and 7.8 tesla background magnetic fields and at heater input energies ranging from 60 mJ/cm/sup 3/ to 1758 mJ/cm/sup 3/ of conductor. The results of these tests and their significance for MHD magnet design and economics are discussed

  6. Superconductivity and Antiferromagnetism in Quasi-one-dimensional Organic Conductors

    OpenAIRE

    Dupuis, N.; Bourbonnais, C.; Nickel, J. C.

    2005-01-01

    We review the current understanding of superconductivity in the quasi-one-dimensional organic conductors of the Bechgaard and Fabre salt families. We discuss the interplay between superconductivity, antiferromagnetism, and charge-density-wave fluctuations. The connection to recent experimental observations supporting unconventional pairing and the possibility of a triplet-spin order parameter for the superconducting phase is also presented.

  7. Construction and power rating of HTS high current conductors

    International Nuclear Information System (INIS)

    Full text: Transmission of very large dc and ac currents over short distances is often required as part of the design of large-scale power devices such superconducting magnet coils and SMES devices or between the power supply and a large machine or distribution point in an industrial plant. Superconducting high-current conductors can be used to transmit large quantities of power with little or no power loss. The near zero voltage drop along such a conductor allows better match to the power supply and enhances the transmission efficiency. Bi-2223/Ag composite tape, produced by powder-in-tube processing, was used to construct and test several prototype high-current conductors including a bus bar and current leads. The bus bar was made by connecting in parallel several stacks of multifilament tape and using an aluminium former for mechanical support. The current leads were constructed by connecting parallel stacks of multifilament tape and then soldering these to copper end caps; structural support was provided by a polycarbonate housing. We report on the test results of the I-V characteristics and dc power loss as a function of transport current (up to 500 A) at 77 K, and compare the results with the ohmic losses of the equivalent conductors made from pure silver metal

  8. Effect of paramagnetic impurities on NMR in superionic conductors

    International Nuclear Information System (INIS)

    Relaxation of mobile 7Li nuclei in LiAlSiO4 and other Li+ conductors is shown by the high temperature T1 : T2 ratio to be caused by paramagnetic impurities. The stationary 27Al, however, is relaxed by quadrupole coupling

  9. Alternative conductor arrangements for ITER TF coil winding pack

    International Nuclear Information System (INIS)

    Different arrangements of round and rectangular conductors and shear plates for the ITER TF coil winding pack have been investigated. Detailed stress analysis for each configuration have been performed for different loading conditions : in-plane force and out-of-plane forces. This analysis includes parametric studies taking into account different mechanical properties of the materials used in the winding pack. With rectangular conductor the peak shear stress remains high and the manufacture of the jacket of the conductor with variable wall thickness raises problems also this solution has not been considered any longer. With round conductors the shear stress generated in the insulation by the out-of-plane force is small compared to the shear stress produced by the in-plane force. - Maximum Von Mises stress in the steel 483 MPa. - Maximum compressive stress in the insulation - 164 MPa. - Maximum interlaminar shear stress in the insulation 38 MPa. Simplification of the manufacturing process including : shear plate machining, transfer of the winding after heat treatment and final assembly of the shear plates and layers have been investigated. (orig.)

  10. Overview of Materials and Power Applications of Coated Conductors Project

    Science.gov (United States)

    Shiohara, Yuh; Taneda, Takahiro; Yoshizumi, Masateru

    2012-01-01

    There are high expectations for coated conductors in electric power applications such as superconducting magnetic energy storage (SMES) systems, power cables, and transformers owing to their ability to contribute to stabilizing and increasing the capacity of the electric power supply grid as well as to reducing CO2 emission as a result of their high critical-current characteristics. Research and development has been performed on wires/tapes and electric power devices worldwide. The Materials and Power Applications of Coated Conductors (M-PACC) Project is a five-year national project in Japan started in 2008, supported by the Ministry of Economy, Trade and Industry (METI) and the New Energy and Industrial Technology Development Organization (NEDO), to develop both coated conductors that meet market requirements and basic technologies for the above-mentioned power applications using coated conductors. In this article, research and development results are reviewed and compared with the interim/final targets of the project, and future prospects are discussed.

  11. An Organic Mixed Ion–Electron Conductor for Power Electronics

    DEFF Research Database (Denmark)

    Malti, Abdellah; Edberg, Jesper; Granberg, Hjalmar;

    2016-01-01

    A mixed ionic–electronic conductor based on nanofibrillated cellulose composited with poly(3,4-ethylene-dioxythio­phene):­poly(styrene-sulfonate) along with high boiling point solvents is demonstrated in bulky electrochemical devices. The high electronic and ionic conductivities of the resulting...

  12. Test results of the FER/ITER conductors in the FENIX test facility

    International Nuclear Information System (INIS)

    The Japan Atomic Energy Research Institute (JAERI) has developed the Advanced Disk and the Hollow Monolithic conductors for the FER/ITER Toroidal Field coils. The advanced Disk conductor is a Cable-in-Conduit conductor which consists of 324 Nb3Sn strands. The Hollow monolithic conductor has hollow cooling channels and 23 Nb3Sn strands. The JA-FENIX sample consists of a pair of straight legs: one leg is the Advanced disk conductor and another is the Hollow Monolithic one. The FENIX facility at the Lawrence Livermore National Laboratory (LLNL) can provide a magnetic field up to 13T on a sample conductor of over 40cm-length. The performance test of the JA-sample was carried out in Autumn 1992. The critical current, the current sharing temperature, and the stability margin of each conductor were measured in this test. These results are presented and discussed

  13. The electrostatics of charged insulating sheets peeled from grounded conductors

    International Nuclear Information System (INIS)

    The physics of a charged, insulating sheet peeled from a ground-plane conductor is examined. Contact charging is ensured by charging a sheet to 10-12 kV with corona to establish intimate electrostatic contact with the underlying conductor. The surface potential is next forced to zero by sweeping the sheet with a stainless-steel brush, and the surface recharged to a new potential between 0 and 11 kV. The sheet is then peeled from the ground plane and its residual charge density is measured. Results show that the residual charge equals the breakdown-limiting value, but its polarity depends on the surface potential acquired just prior to peeling. The results have relevance to studies of industrial webs and insulating sheets.

  14. Chemical solution deposition: a path towards low cost coated conductors

    International Nuclear Information System (INIS)

    The achievement of low cost deposition techniques for high critical current YBa2Cu3O7 coated conductors is one of the major objectives to achieve a widespread use of superconductivity in power applications. Chemical solution deposition techniques are appearing as a very promising methodology to achieve epitaxial oxide thin films at a low cost, so an intense effort is being carried out to develop routes for all chemical coated conductor tapes. In this work recent achievements will be presented towards the goal of combining the deposition of different type of buffer layers on metallic substrates based on metal-organic decomposition with the growth of YBa2Cu3O7 layers using the trifluoroacetate route. The influence of processing parameters on the microstructure and superconducting properties will be stressed. High critical currents are demonstrated in 'all chemical' multilayers

  15. Structural Parameter Optimization of Multilayer Conductors in HTS Cable

    Institute of Scientific and Technical Information of China (English)

    Yan Mao; Jie Qiu; Xin-Ying Liu; Zhi-Xuan Wang; Shu-Hong Wang; Jian-Guo Zhu; You-Guang Guo; Zhi-Wei Lin; Jian-Xun Jin

    2008-01-01

    In this paper, the design optimization of the structural parameters of multilayer conductors in high temperature superconducting (HTS) cable is reviewed. Various optimization methods, such as the particle swarm optimization (PSO), the genetic algorithm (GA), and a robust optimization method based on design for six sigma (DFSS), have been applied to realize uniform current distribution among the multi- layer HTS conductors. The continuous and discrete variables, such as the winding angle, radius, and winding direction of each layer, are chosen as the design parameters. Under the constraints of the mechanical properties and critical current, PSO is proven to be a more powerful tool than GA for structural parameter optimization, and DFSS can not only achieve a uniform current distribution, but also improve significantly the reliability and robustness of the HTS cable quality.

  16. Current distribution for conductors in variable external magnetic fields

    International Nuclear Information System (INIS)

    This work presents the results of a study on current distribution for compact cable shaped conductors with several elements (filaments) that have fluid cooling. This cables are used in facilities for fusion with superconducting magnets. Current distribution between the filaments of the cable is not uniform. Flow leaps can appear. Taking into account certain simplifying hypotheses and the internal inductance on the basis of calculations, the basic equation results that is specific to the current distribution. The analysis of the solutions to the basic equation is carried out by means of the Bessel functions. In the last part of the work to examples are presented: 1. The case of a initial profile of the current estimated by a Bessel modified function; 2. The case of a magnet of alternating current where the magnetic field acting on the conductor is proportional to its current. (author)

  17. Coulomb correlation effects in quasi-one-dimensional conductors

    International Nuclear Information System (INIS)

    Recent results on the role of electron-electron (e-e) interactions - ''correlation effects'' - in quasi-one-dimensional conductors are reviewed. Within the Peierls-Hubbard model, the consequences of short range (on-site U and nearest neighbor V) e-e interactions for ground state properties, nonlinear excitations, and optical absorption are examined. Techniques include quantum Monte Carlo and weak and strong coupling perturbative arguments. 26 refs., 2 figs

  18. Assessment of seasonal static thermal ratings of overhead transmission conductors

    Czech Academy of Sciences Publication Activity Database

    Heckenbergerová, Jana; Musílek, P.; Filimonenkov, K.

    Piscataway : IEEE, 2011, s. 1-8. ISBN 978-1-4577-1001-8. ISSN 1944-9925. [PES 2011. Detroit (US), 24.07.2011-29.07.2011] Grant ostatní: GA AV ČR(CZ) M100300904 Institutional research plan: CEZ:AV0Z10300504 Keywords : transmission line * overhead conductor * weather conditions * thermal rating * ampacity * risk * aging Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use

  19. Activation volumes of some superionic conductors with the fluorite structure

    International Nuclear Information System (INIS)

    Information about defect and conduction mechanisms of ionic conductors can be obtained by studying the pressure and temperature dependence of the electrical conductivity. The existence of several activated regions of conduction was found. The activation volumes, which are extracted from the pressure data, are small and positive throughout the temperature range investigated. This implies that Frenkel defects are dominant up to near the melting points of the materials examined

  20. Group Members’ Assessment of Their Conductor in Small Analytic Group

    OpenAIRE

    Vlastelica, Mirela; Urlić, Ivan

    2004-01-01

    In this pilot study the authors present the group members’ assessment of their conductor in group analysis – the treatment conducted in accordance with concept »groupas- a-whole« of S. H. Foulkes. There will be presented the results obtained by scale for evaluation of characteristics of the group therapist. In the scale, developed by the authors of the study, there were 30 items and by factorial analysis it gave three interpretable factors: authenticity, empathy and distrust. B...

  1. Equivalent electric circuit of a carbon nanotube based molecular conductor

    CERN Document Server

    Yam, ChiYung; Wang, Fan; Li, Xiaobo; Chen, GuanHua; Zheng, Xiao; Matsuda, Yuki; Tahir-Kheli, Jamil; Goddard, William A

    2008-01-01

    We apply our first-principles method to simulate the transient electrical response through carbon nanotube based conductors under time-dependent bias voltages, and report the dynamic conductance for a specific system. We find that the electrical response of the carbon nanotube device can be mapped onto an equivalent classical electric circuit. This is confirmed by studying the electric response of a simple model system and its equivalent circuit.

  2. Non-equilibrium noise in a mesoscopic conductor: microscopic analysis

    OpenAIRE

    Altshuler, B. L.; Levitov, L.S.; Yakovets, A. Yu.

    1994-01-01

    Current fluctuations are studied in a mesoscopic conductor using non-equilibrium Keldysh technique. We derive a general expression for the fluctuations in the presence of a time dependent voltage, valid for arbitrary relation between voltage and temperature. Two limits are then treated: a pulse of voltage and a DC voltage. A pulse of voltage causes phase sensitive current fluctuations for which we derive microscopically an expression periodic in $\\int V(t)dt$ with the period $h/e$. Applied to...

  3. Electromigration induced resistance changes in passivated aluminum thin film conductors

    OpenAIRE

    Möckl, U. E.; Lloyd, J. R.; Arzt, Eduard

    1993-01-01

    The relative change in resistance due to electromigration was studied in thin (0.7 µm) film conductors of Al-0.5% Cu alloy passivated with a 1 µm thick glass passivation using a sensitive AC bridge technique. In contrast to previous experiments performed on unpassivated structures where a roughly linear resistance increase was observed, a saturation value for the resistance increase was observe which was seen to be a function of temperature and the applied current density. The results were fo...

  4. Modeling Wet-Snow Shedding from Current-Carrying Conductors

    OpenAIRE

    Olqma, Ossama; Kollar, László E.; Farzaneh, Masoud; Pellet, Laure

    2009-01-01

    The initiation of wet-snow shedding from currentcarrying conductors was studied experimentally and theoretically. A suspended cable with cylindrical snow accretion was considered, and some of the snow properties at the end of sleeve were measured and calculated until snow shedding. The current in the cable appears to be a heat source which accelerates snow melting, similarly to air temperatures above freezing, wind and heat radiation. All of these effects were taken into account to study how ...

  5. Chemical strategies for modifications of the solar cell process, from wafering to emitter diffusion; Chemische Ansaetze zur Neuordnung des Solarzellenprozesses ausgehend vom Wafering bis hin zur Emitterdiffusion

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Kuno

    2009-11-06

    The paper describes the classic standard industrial solar cell based on monocrystalline silicon and describes new methods of fabrication. The first is an alternative wafering concept using laser microjet cutting instead of multiwire cutting. This method originally uses pure, deionized water; it was modified so that the liquid jet will not only be a liquid light conductor but also a transport medium for etching fluids supporting thermal abrasion of silicon by the laser jet. Two etching fluids were tested experimentally; it was found that water-free fluids based on perfluorinated solvents with very slight additions of gaseous chlorine are superior to all other options. In the second section, the wet chemical process steps between wafering and emitter diffusion (i.e. the first high-temperature step) was to be modified. Alternatives to 2-propanol were to be found in the experimental part. Purification after texturing was to be rationalized in order to reduce the process cost, either by using less chemical substances or by achieving shorter process times. 1-pentanol and p-toluolsulfonic acid were identified as two potential alternatives to 2-propanol as texture additives. Finally, it could be shown that wire-cut substrates processed with the new texturing agents have higher mechanical stabilities than substrates used with the classic texturing agent 2-propanol. [German] Im ersten Kapitel wird die klassische Standard-Industrie-Solarzelle auf der Basis monokristallinen Siliziums vorgestellt. Der bisherige Herstellungsprozess der Standard-Industrie-Solarzelle, der in wesentlichen Teilen darauf abzielt, diese Verluste zu minimieren, dient als Referenz fuer die Entwicklung neuer Fertigungsverfahren, wie sie in dieser Arbeit vorgestellt werden. Den ersten thematischen Schwerpunkt bildet die Entwicklung eines alternativen Wafering-Konzeptes zum Multi-Drahtsaegen. Die Basis des neuen, hier vorgestellten Wafering-Prozesses bildet das Laser-Micro-Jet-Verfahren. Dieses System

  6. High-field thermal transports properties of REBCO coated conductors

    CERN Document Server

    Bonura, M

    2015-01-01

    The use of REBCO coated conductors is envisaged for many applications, extending from power cables to high-field magnets. Whatever the case, thermal properties of REBCO tapes play a key role for the stability of superconducting devices. In this work, we present the first study on the longitudinal thermal conductivity (k) of REBCO coated conductors in magnetic fields up to 19 T applied both parallelly and perpendicularly to the thermal-current direction. Copper-stabilized tapes from six industrial manufacturers have been investigated. We show that zero-field k of coated conductors can be calculated with an accuracy of ‡ 15% from the residual resistivity ratio of the stabilizer and the Cu/non-Cu ratio. Measurements performed at high fields have allowed us to evaluate the consistency of the procedures generally used for estimating in-field k in the framework of the Wiedemann-Franz law from an electrical characterization of the materials. In-field data are intended to provide primary ingredients for the ...

  7. Nexans advances in all CSD route for REBCO coated conductors

    International Nuclear Information System (INIS)

    Development of REBCO coated conductors (CC) at Nexans SuperConductors (NSC) is focused on all chemical solution deposition (CSD) route that promises the best performance-to-price ratio in long lengths. The feasibility of all CSD approach is shown on the lab scale: using metalorganic deposition (MOD), NSC was able to produce YBCO/CeO2/LZO/NiW CCs with Jc(77 K,sf)=0.5 MA/cm2. The major advance of NSC on a semi-industrial scale is the use of MOD route for production of high-quality La2Zr2O7 (LZO) coated NiW RABITS in lengths up to 12 m. With those substrates, it is possible to produce CCs with the simplest (one-buffer) architecture by depositing REBCO using other techniques (ISD at Theva, Ismaning; MOCVD at IOT, Braunschweig; HLPE at University of Cambridge, UK). The best short sample Ic=280, 120 and 100 A/cm-width for HLPE, ISD, and MOCVD, respectively First long-length conductors show transport Ic=40 A (10m-long, ISD). Further work is focused on optimisation of the already established mixed (MOD+PVD) approaches, understanding optimum architecture and processing conditions for the all-CSD route and developing tools for scaling those conditions to long-length production. (orig.)

  8. MHD Modeling of Conductors at Ultra-High Current Density

    Energy Technology Data Exchange (ETDEWEB)

    Asay, J.R.; Desjarlais, M.P.; Douglas, M.R.; Frese, M.H.; Hall, C.A.; Morse, R.L.; Reisman, D.; Rosenthal, S.E.; Spielman, R.B.; Stygar, W.A.

    1999-06-30

    In conjunction with ongoing high-current experiments on Sandia National Laboratories' Z accelerator we have revisited a problem first described in detail by Heinz Knoepfel. MITLs of previous pulsed power accelerators have been in the 1-Tesla regime. Z's disc transmission line (downstream of the current addition) is in a 100-1200 Tesla regime, so its conductors cannot be modeled simply as static infinite conductivity boundaries. Using the MHD code MACH2 we have been investigating conductor hydrodynamics, characterizing the joule heating, magnetic field diffusion, and material deformation, pressure, and velocity over a range of current densities, current rise-times, and conductor materials. Three purposes of this work are ( 1) to quantify power flow losses owing to ultra-high magnetic fields, (2) to model the response of VISAR diagnostic samples in various configurations on Z, and (3) to incorporate the most appropriate equation of state and conductivity models into our MHD computations. Certain features are strongly dependent on the details of the conductivity model. Comparison with measurements on Z will be discussed.

  9. MHD Modeling of Conductors at Ultra-High Current Density

    International Nuclear Information System (INIS)

    In conjunction with ongoing high-current experiments on Sandia National Laboratories' Z accelerator, the authors have revisited a problem first described in detail by Heinz Knoepfel. Unlike the 1-Tesla MITLs of pulsed power accelerators used to produce intense particle beams, Z's disc transmission line (downstream of the current addition) is in a 100--1,200 Tesla regime, so its conductors cannot be modeled simply as static infinite conductivity boundaries. Using the MHD code MACH2 they have been investigating the conductor hydrodynamics, characterizing the joule heating, magnetic field diffusion, and material deformation, pressure, and velocity over a range of current densities, current rise-times, and conductor materials. Three purposes of this work are (1) to quantify power flow losses owing to ultra-high magnetic fields, (2) to model the response of VISAR diagnostic samples in various configurations on Z, and (3) to incorporate the most appropriate equation of state and conductivity models into the MHD computations. Certain features are strongly dependent on the details of the conductivity model

  10. Charge densities and charge noise in mesoscopic conductors

    Indian Academy of Sciences (India)

    M Büttiker

    2002-02-01

    We introduce a hierarchy of density of states to characterize the charge distribution in a mesoscopic conductor. At the bottom of this hierarchy are the partial density of states which represent the contribution to the local density of states if both the incident and the out-going scattering channel is prescribed. The partial density of states play a prominent role in measurements with a scanning tunneling microscope on multiprobe conductors in the presence of current flow. The partial density of states determine the degree of dephasing generated by a weakly coupled voltage probe. In addition the partial density of states determine the frequency-dependent response of mesoscopic conductors in the presence of slowly oscillating voltages applied to the contacts of the sample. The partial density of states permit the formulation of a Friedel sum rule which can be applied locally. We introduce the off-diagonal elements of the partial density of states matrix to describe charge fluctuation processes. This generalization leads to a local Wigner–Smith life-time matrix.

  11. Oxygen and cation diffusion in YBCO coated conductors

    International Nuclear Information System (INIS)

    Biaxially textured YBa2Cu3Ox (YBCO) films 0.3 μm thick were deposited on single-crystal LaAlO3 and buffered Hastelloy C276 substrates. After annealing in 18O at 400 deg. C, secondary-ion mass spectrometry was used to determine oxygen-diffusion profiles and several cation-diffusion profiles within the various layers of the conductors. Oxygenation in the YBCO/LaAlO3 specimen was relatively slow and hours would be required for full oxygenation of the YBCO. Oxygen diffusion was rapid in the coated conductor. It was dominated by diffusion along a-b planes and full oxygenation of a 0.3-μm-thick YBCO layer was achieved in several minutes. Cation interdiffusion was limited in the YBCO/LaAlO3 specimen, but was significant within the coated conductor. Although Cu diffused out of the superconductor, an SrTiO3 layer between textured MgO and YBCO limited diffusion of cations from the various substrate layers into the superconductor

  12. Oxygen and cation diffusion in YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Tsukui, S.; Koritala, R.E.; Li, M.; Goretta, K.C.; Adachi, M.; Baker, J.E.; Routbort, J.L

    2003-10-15

    Biaxially textured YBa{sub 2}Cu{sub 3}O{sub x} (YBCO) films 0.3 {mu}m thick were deposited on single-crystal LaAlO{sub 3} and buffered Hastelloy C276 substrates. After annealing in {sup 18}O at 400 deg. C, secondary-ion mass spectrometry was used to determine oxygen-diffusion profiles and several cation-diffusion profiles within the various layers of the conductors. Oxygenation in the YBCO/LaAlO{sub 3} specimen was relatively slow and hours would be required for full oxygenation of the YBCO. Oxygen diffusion was rapid in the coated conductor. It was dominated by diffusion along a-b planes and full oxygenation of a 0.3-{mu}m-thick YBCO layer was achieved in several minutes. Cation interdiffusion was limited in the YBCO/LaAlO{sub 3} specimen, but was significant within the coated conductor. Although Cu diffused out of the superconductor, an SrTiO{sub 3} layer between textured MgO and YBCO limited diffusion of cations from the various substrate layers into the superconductor.

  13. Oxygen and cation diffusion in YBCO coated conductors

    Science.gov (United States)

    Tsukui, S.; Koritala, R. E.; Li, M.; Goretta, K. C.; Adachi, M.; Baker, J. E.; Routbort, J. L.

    2003-10-01

    Biaxially textured YBa 2Cu 3O x (YBCO) films 0.3 μm thick were deposited on single-crystal LaAlO 3 and buffered Hastelloy C276 substrates. After annealing in 18O at 400 °C, secondary-ion mass spectrometry was used to determine oxygen-diffusion profiles and several cation-diffusion profiles within the various layers of the conductors. Oxygenation in the YBCO/LaAlO 3 specimen was relatively slow and hours would be required for full oxygenation of the YBCO. Oxygen diffusion was rapid in the coated conductor. It was dominated by diffusion along a- b planes and full oxygenation of a 0.3-μm-thick YBCO layer was achieved in several minutes. Cation interdiffusion was limited in the YBCO/LaAlO 3 specimen, but was significant within the coated conductor. Although Cu diffused out of the superconductor, an SrTiO 3 layer between textured MgO and YBCO limited diffusion of cations from the various substrate layers into the superconductor.

  14. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  15. Low-profile metamaterial-based L-band antennas

    Science.gov (United States)

    Burokur, Shah Nawaz; Lepage, Anne-Claire; Varault, Stefan; Begaud, Xavier; Piau, Gérard-Pascal; de Lustrac, André

    2016-04-01

    The aim of the present contribution is to show that metasurfaces such as reactive impedance surfaces (RIS) and artificial magnetic conductors can be efficiently used in the design of low-profile circularly polarized L-band antennas. We present the design and simulation of the compact and low-profile antennas. The solution based on RIS will be compared to a circularly polarized microstrip patch antenna using the same materials in order to prove the benefit of metasurfaces. The engineered metasurfaces allow increasing the bandwidths with few modifications on the thickness and the overall antenna size.

  16. A Boundary Element Solution to the Problem of Interacting AC Fields in Parallel Conductors

    Directory of Open Access Journals (Sweden)

    Einar M. Rønquist

    1984-04-01

    Full Text Available The ac fields in electrically insulated conductors will interact through the surrounding electromagnetic fields. The pertinent field equations reduce to the Helmholtz equation inside each conductor (interior problem, and to the Laplace equation outside the conductors (exterior problem. These equations are transformed to integral equations, with the magnetic vector potential and its normal derivative on the boundaries as unknowns. The integral equations are then approximated by sets of algebraic equations. The interior problem involves only unknowns on the boundary of each conductor, while the exterior problem couples unknowns from several conductors. The interior and the exterior problem are coupled through the field continuity conditions. The full set of equations is solved by standard Gaussian elimination. We also show how the total current and the dissipated power within each conductor can be expressed as boundary integrals. Finally, computational results for a sample problem are compared with a finite difference solution.

  17. Transport ac losses in Bi-2223 multifilamentary tapes - conductor materials aspect

    International Nuclear Information System (INIS)

    Transport ac losses in technical superconductors based on Bi-2223 tape material are influenced by many parameters. The major factors that define the ac performance of such conductors are the following: the size and number of filaments, their geometrical arrangement in the cross-section of the conductor, the twist pitch length, the resistivity of the matrix, the presence of oxide barriers around the filaments and deformation procedures such as sequential pressing or rolling followed by appropriate thermal treatment. In the present paper the above aspects are addressed from the viewpoint of the materials science of technical conductor design. Transport ac losses at power frequencies in different types of Bi-2223 conductor are presented and analysed. The results of conductor design analysis with respect to the coexistence of the superconductor with other materials in the conductor structure are presented. New concepts for minimization of the transport ac losses are discussed in detail. (author)

  18. Photonic band gap materials

    International Nuclear Information System (INIS)

    An overview of the theoretical and experimental efforts in obtaining a photonic band gap, a frequency band in three-dimensional dielectric structures in which electromagnetic waves are forbidden, is presented

  19. Promoting orchestral performance : the interplay between musicians' mood and a conductor's leadership style

    OpenAIRE

    Boerner, Sabine; Streit, Christian von

    2007-01-01

    This study investigates the degree to which a conductor s transformational leadership and orchestral musicians positive group mood have a beneficial effect on orchestral performance. The authors study the assertion that there is an interaction effect of conductor s transformational leadership style and group mood in the orchestra. In this view, neither the conductor s transformational leadership nor the musicians positive group mood alone foster success; only the interaction between transfo...

  20. Studies of the strain-dependent properties of A15 filamentary conductors at Brookhaven National Laboratory

    International Nuclear Information System (INIS)

    Work at BNL pertaining to the strain response of filamentary bronze-processed superconductors is reviewed. This work includes the intrinsic strain dependence of the critical properties of A15 structure compounds, the nature of the initial internal strain state of composite conductors, and the interplay between these residual strains and applied strains which governs the response of the conductor to external strain. Some factors which can enhance the strain tolerances of filamentary conductors are briefly discussed

  1. The performance test and analysis of the third and fourth China PF conductor for ITER

    International Nuclear Information System (INIS)

    Highlights: • The Tcs of PFCN4 conductor is consistent with the calculated result. • The Tcs of PFCN3 conductor is a little larger than calculated result. • The AC loss before and after cycling of PFCN3 and PFCN4 is not the same. • The cable layout or the cycling electromagnetic force influence the AC loss. • The MQE performance of PFCN3 after cycling is decreased obvious. - Abstract: The third Chinese PF conductor for ITER PF5 (PFCN3) and the fourth Chinese PF conductor for ITER PF2/3/4 (PFCN4) conductor in Phase II were manufactured in ASIPP and tested in the SULTAN facility. This paper introduces the PFCN3 and PFCN4 sample manufacture, including strand, sample preparation, current sharing temperature (Tcs), AC loss and Minimum Quench Energy (MQE) test performance of PFCN3 and PFCN4 conductors. The Tcs test result of PFCN4 conductor is consistent with the calculated result used the strand scaling and the Tcs test result of PFCN3 conductor is a little larger than calculated result, whose maximum difference is about 0.2 K. According to the SULTAN test result, the Tcs performance of both PFCN3 and PFCN4 conductor sample could meet the ITER requirement

  2. Development and characterization of aluminum stranded water cooled conductor for rapid cycling synchrotron magnets

    International Nuclear Information System (INIS)

    Magnet coils of rapid cycling synchrotron are subjected to time varying magnetic fields and a special water cooled stranded conductor is preferred for making magnet coils to reduce eddy current losses, magnetic field inhomogeneity and operating costs of magnets. A continuous length (∼ 50 m) aluminum stranded water cooled conductor is indigenously developed. Five stranded magnet coils are wound and epoxy resin impregnated as per the technical requirements. The stranded conductor magnet coils are assembled with a laminated dipole magnet core for their electrical characterization. The development of water cooled aluminum stranded conductor, characterization of stranded magnet coils will be discussed in this paper. (author)

  3. Development of the KfK NET toroidal field coil react and wind conductor

    International Nuclear Information System (INIS)

    In the frame of the Euratom Fusion Technology program an A15 forced flow cooled conductor for the toroidal field (TF) coils of the Next European Torus (NET) was developed at KfK Karlsruhe. The conductor is based on the bronze route of Nb3Sn. It was designed as a react and wind conductor in a sandwich type where the flat Nb3Sn Rutherford cable was enclosed between two Cu stabilizers based on roebeled Cu profiles. A subsize conductor at the scale 1:1.75 was fabricated for developing the industrial fabrication procedure and testing the electrical properties within an acceptable cost frame. For the heat treatment of the Rutherford cable a suitable process was developed. No unexpected degradations were found on samples taken at different fabrication stages and tested in the FBI facility at KfK. In a late stage of development the NET parameters were changed which loaded the conductor with 10 times higher field transients caused by plasmas disruption with respect to the original specifications. A detailed analysis showed that the conductor fulfilled further all specifications except the field transients of the plasma disruption where the conductor will quench. The development of the Nb3Sn conductor in react and wind technique demonstrate that this conductor type is feasible using the common manufacturing techniques of large coils which were already successfully demonstrated in the Large Coil Task and in the KfK-Polo project. (orig.)

  4. Calculation of the surface effect in the ferromagnetic conductor with the harmonic electromagnetic field

    Science.gov (United States)

    Nosov, G. V.; Kuleshova, E. O.; Vassilyeva, Yu Z.; Elizarov, A. I.

    2016-04-01

    The authors of the paper have obtained formulas for analytical calculation of the constants with the harmonic electromagnetic field, which characterize the surface layer (a skin layer) of the ferromagnetic conductors in case of heating and nonlinear magnetic properties, which can be used for practical calculation of the electromagnetic screens, rotors of the electrical machines and inductive heating installations. A nonlinear dependence of the magnetic induction on the magnetic tension of the ferromagnetic conductor is replaced by one or two linear sections. It is considered that the skin layer of the conductor has constant quantities of the specific conductivity and averaged temperature. Linear electrodynamics equations are solved for the conductive half-space. Parameters of the ferromagnetic conductor's surface layer are calculated: magnetic permeability, the thickness of the skin layer and its averaged temperature, exposure time of the electromagnetic field on the conductor with the established maximum temperature on the conductor's surface, pressure of the field on the conductor and its resistance, inductivity of the internal magnetic field in the conductor, the thermal energy capacity. The methods credibility is confirmed with the concurrence of the resistance and inductiviry of the ferromagnetic conductor with analogous quantities from other methods.

  5. Study on galloping behavior of iced eight bundle conductor transmission lines

    Science.gov (United States)

    Zhou, Linshu; Yan, Bo; Zhang, Liang; Zhou, Song

    2016-02-01

    Wind tunnel test was carried out to obtain the aerodynamic coefficients of an eight bundle conductor accreted with crescent-shaped ice. A user-defined cable element with torsional degree of freedom is developed in ABAQUS software to capture the torsional deformation of the iced conductors during galloping. By means of the user-defined cable element, different damping ratios in in-plane, out-of-plane and torsional directions of the conductors can be defined and the aerodynamic forces varying with their motion status can be exerted on the conductors conveniently when ABAQUS is used to simulate galloping of transmission lines. A wind tunnel test to model galloping of an iced eight bundle conductor segment was carried out, and the validity of the numerical simulation method is demonstrated by the agreement of the galloping orbit of the bundle conductor segment model recorded in the test and that by the numerical simulation. Furthermore, galloping behavior, including dynamic responses, galloping orbits, frequencies, vibration modes and amplitudes, of typical iced eight bundle conductor transmission lines in the cases of different span lengths, initial tensions in sub-conductors, wind velocities, angles of wind attack and damping ratios is studied, and the galloping behavior of the lines with internal resonance conditions is discussed. The obtained results may provide a fundamental tool for the development of anti-galloping techniques of eight bundle conductor transmission lines.

  6. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.;

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory are co...

  7. Flat Band Quastiperiodic Lattices

    Science.gov (United States)

    Bodyfelt, Joshua; Flach, Sergej; Danieli, Carlo

    2014-03-01

    Translationally invariant lattices with flat bands (FB) in their band structure possess irreducible compact localized flat band states, which can be understood through local rotation to a Fano structure. We present extension of these quasi-1D FB structures under incommensurate lattices, reporting on the FB effects to the Metal-Insulator Transition.

  8. Solderability study of RABiTS-based YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yifei [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6305 (United States); Duckworth, Robert C., E-mail: duckworthrc@ornl.gov [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6305 (United States); Ha, Tam T.; Gouge, Michael J. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6305 (United States)

    2011-08-15

    Study examines the implication of solder and flux selection in YBCO splice joints. Focus is on commercially available RABiTS-based YBCO coated conductors. Solderability varied with solder and flux for three different stabilizations tested. Resistivity of stabilizer was dominant factor in splice joint resistance. Solder materials affected splice joint resistance when solderability was poor. The solderability of commercially available YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) coated conductors that were made from Rolling Assisted Biaxially Textured Substrates (RABiTS)-based templates was studied. The coated conductors, also known as second-generation (2G) high temperature superconductor (HTS) wires (in the geometry of flat tapes about 4 mm wide), were laminated with copper, brass, or stainless steel strips as stabilizers. To understand the factors that influence their solderability, surface profilometry and scanning electron microscopy were used to characterize the wire surfaces. The solderability of three solders, 52In48Sn, 67Bi33In, and 100In (wt.%), was evaluated using a standard test (IPC/ECA J-STD-002) and with two different commercial fluxes. It was found that the solderability varied with the solder and flux but the three different wires showed similar solderability for a fixed combination of solder and flux. Solder joints of the 2G wires were fabricated using the tools and the procedures recommended by the HTS wire manufacturer. The solder joints were made in a lap-joint geometry and with the superconducting sides of the two wires face-to-face. The electrical resistances of the solder joints were measured at 77 K, and the results were analyzed to qualify the soldering materials and evaluate the soldering process. It was concluded that although the selection of soldering materials affected the resistance of a solder joint, the resistivity of the stabilizer was the dominant factor.

  9. Microstructure of Ice Accretions Grown on Aluminum Conductors.

    Science.gov (United States)

    Laforte, Jean-Louis; Phan, Luan C.; Felin, Béatrice

    1983-07-01

    In order to study the microstructure of glaze and rime deposits formed on the conductors of power lines, ice accretions are grown on a slowly rotating aluminum cylinder placed in the working section of a wind tunnel. The growth conditions cover both dry and wet regimes in the air temperature interval between 2 and 15°C and are close to those commonly prevailing in natural icing storms near the ground: liquid water contents vary from 0.4 to 0.8 g m3 and wind speed from 4 to 20 m s1; thew values are lower than those usually used in hail simulation studies. Four droplet spectra of 12, 22, 38 and 98 m mean volume diameter were used. The air bubble features of glaze and rime deposits grown in the abovementioned conditions show that the degree of transparency and the layering of the fine air bubbles strongly depend on the deposit temperatures and the intensity of accretion. On the other hand, crystal textures reveal that the mean width of ice crystals depends mainly on the ambient temperature and to a lesser degree on the wind velocity, particularly at low wind speeds. Mean droplet size and liquid water content seem to have little effect upon the crystal mean width. In addition, it is found that in the layer of ice closest to the aluminium cylinder, the crystal mean width increases with the radial distance from the conductor surface and this increase is more marked at low air temperatures. This effect cannot be attributed to the thermal conductivity of the substrate, but probably to the nucleation rate of ice crystals near the ice-conductor interface.

  10. Improving Students' Conceptual Understanding of Conductors and Insulators

    CERN Document Server

    Bilak, Joshua

    2016-01-01

    We examine the difficulties that introductory physics students, undergraduate physics majors, and physics graduate students have with concepts related to conductors and insulators covered in introductory physics by giving written tests and interviewing a subset of students. We find that even graduate students have serious difficulties with these concepts. We develop tutorials related to these topics and evaluate their effectiveness by comparing the performance on written pre-/post-tests and interviews of students who received traditional instruction vs. those who learned using tutorials.

  11. Salud vial: ¿el conductor a terapia?

    OpenAIRE

    Alonso Plá, Francisco Manuel; Esteban Martínez, Cristina; Calatayud Miñana, Constanza; Alamar Rocatí, Beatriz; Fernández Fernández, Cesáreo; Medina Sarmiento, José Eugenio

    2009-01-01

    El Instituto Universitario de Investigación en Tráfico y Seguridad Vial (INTRAS) y Attitudes (programa social de Audi), tras la publicación de los libros "Salud vial: Teoría y prácticas de los trastornos físicos y psíquicos en la conducción." y "Salud vial: Diagnóstico de los conductores españoles.", se plantearon como actividad complementaria la realización de unas jornadas que cumplieran los siguientes objetivos: • Permitir avanzar en el conocimiento y la implementación de medidas que co...

  12. Application of the Lifshitz Theory to Poor Conductors

    International Nuclear Information System (INIS)

    The Lifshitz formula for dispersive forces is generalized to the materials, which cannot be described with the local dielectric response. The principal nonlocality of poor conductors is related to the finite screening length of the penetrating field and collisional relaxation; at low temperatures the role of collisions plays the Landau damping. Spatial dispersion makes the theory self-consistent. Our predictions are compared with the recent experiment. It is demonstrated that at low temperatures Casimir-Lifshitz entropy disappears as T in the case of degenerate plasma and as T2 for the nondegenerate one

  13. Magnet and conductor developments for the Mirror Fusion Program

    International Nuclear Information System (INIS)

    The conductor development and the magnet design and construction for the MFTF are described. Future plans for the Mirror Program and their influence on the associated superconductor development program are discussed. Included is a summary of the progress being made to develop large, high-field, multifilamentary Nb3Sn superconductors and the feasibility of building a 12-T yin-yang set of coils for the machine to follow MFTF. In a further look into the future, possible magnetic configurations and requirements for mirror reactors are surveyed

  14. Evaluation of the ITER cable in conduit conductor heat transfer

    International Nuclear Information System (INIS)

    Convective heat transfer correlations in dual channel Cable In Conduit Conductor (CICC) are presented as functions of friction factor, and based on the Reynolds-Colburn analogy using the Stanton number. The developed thermohydraulic model determines helium temperatures in both channels, with the real geometrical spiral perforation. It is applied with pertinence to the Poloidal Field Full Size Joint Sample (PF-FSJS) and shows good agreement between the experimental measurements and the calculated temperatures, characterised by a 0.43 m space constant. The heat load applied in the bundle region induces density imbalance; the gravity effect in this vertical sample is evaluated and discussed. (authors)

  15. Loss and Inductance Investigation in Superconducting Cable Conductors

    DEFF Research Database (Denmark)

    Olsen, Søren Krüger; Tønnesen, Ole; Træholt, Chresten;

    1999-01-01

    the layers are therefore studied theoretically. The current distribution between the superconducting layers is monitored as a function of transport current, and the results are compared with the expected current distribution given by our electrical circuit model.The AC-losses are measured as a...... Hz) the AC-loss was measured on cable #2 to 0.6W/mxphase. This is, to our knowledge, the lowest AC-loss (at 2kA and 77K) of a high temperature superconducting cable conductor reported so far....

  16. Flux line lattice in type II super conductors

    International Nuclear Information System (INIS)

    The shear modules C66 of the flux line lattice in type II super conductors can be obtained from a two body interaction between the flux lines even at large inductions B ∼ HC2. The potential is composed of a repulsive and an attractive part and has a range diverging at HC2. An explicit expression for the Ginzberg-Landau C66 is given for arbitrary B and k' (G-L parameter). The graph for C66 exhibits the expected maximum at a certain value of b. (author)

  17. An FMM-FFT accelerated integral equation solver for characterizing electromagnetic wave propagation in mine tunnels and galleries loaded with conductors

    KAUST Repository

    Yücel, Abdulkadir C.

    2014-07-01

    Reliable wireless communication and tracking systems in underground mines are of paramount importance to increase miners\\' productivity while monitoring the environmental conditions and increasing the effectiveness of rescue operations. Key to the design and optimization of such systems are electromagnetic (EM) simulation tools capable of analyzing wave propagation in electromagnetically large mine tunnels and galleries loaded with conducting cables (power, telephone) and mining equipment (trolleys, rails, carts), and potentially partially obstructed by debris from a cave-in. Current tools for simulating EM propagation in mine environments leverage (multi-) modal decompositions (Emslie et. al., IEEE Trans. Antennas Propag., 23, 192-205, 1975; Sun and Akyildiz, IEEE Trans. Commun., 58, 1758-1768, 2010), ray-tracing techniques (Zhang, IEEE Tran. Vehic. Tech., 5, 1308-1314, 2003), or full wave methods. Modal approaches and ray-tracing techniques cannot accurately account for the presence of conductors, intricate details of transmitters/receivers, wall roughness, or unstructured debris from a cave-in. Classical full-wave methods do not suffer from such restrictions. However, they require prohibitively large computational resources when applied to the analysis of electromagnetically large tunnels loaded with conductors. Recently, an efficient hybrid method of moment and transmission line solver has been developed to analyze the EM wave propagation inside tunnels loaded with conductors (Brocker et. al., in Proc IEEE AP-S Symp, pp.1,2, 2012). However, the applicability of the solver is limited to the characterization of EM wave propagation at medium frequency band.

  18. The influence of impurity on the critical thickness of the CeO2 buffer layer for coated conductors

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The lattice parameters, band structure, density of state and elastic constant of RE-doped CeO2 (RE=Sm, Gd, Dy), the buffer material for coated HTS conductors, are calculated using the plane-wave method with pseudopotentials based on the density functional theory (DFT) of first-principle. The rule and mechanism of the effect of rare earth impurity on the critical thickness of the CeO2 buffer layer are investigated. It is found that, in the range of the calculation, the changes of the lattice volume V and elastic constant E of CeO2 with the impurity are mainly determined by the increased electrons ne of the system. The relationship of the elastic constant E and increased electrons ne is established. It is indicated that the critical thickness of the CeO2 single buffer layer doped with Sm, Gd, and Dy may be enhanced by 22%, 43% and 33%, respectively.

  19. A Na(+) Superionic Conductor for Room-Temperature Sodium Batteries.

    Science.gov (United States)

    Song, Shufeng; Duong, Hai M; Korsunsky, Alexander M; Hu, Ning; Lu, Li

    2016-01-01

    Rechargeable lithium ion batteries have ruled the consumer electronics market for the past 20 years and have great significance in the growing number of electric vehicles and stationary energy storage applications. However, in addition to concerns about electrochemical performance, the limited availability of lithium is gradually becoming an important issue for further continued use and development of lithium ion batteries. Therefore, a significant shift in attention has been taking place towards new types of rechargeable batteries such as sodium-based systems that have low cost. Another important aspect of sodium battery is its potential compatibility with the all-solid-state design where solid electrolyte is used to replace liquid one, leading to simple battery design, long life span, and excellent safety. The key to the success of all-solid-state battery design is the challenge of finding solid electrolytes possessing acceptable high ionic conductivities at room temperature. Herein, we report a novel sodium superionic conductor with NASICON structure, Na3.1Zr1.95Mg0.05Si2PO12 that shows high room-temperature ionic conductivity of 3.5 × 10(-3) S cm(-1). We also report successful fabrication of a room-temperature solid-state Na-S cell using this conductor. PMID:27572915

  20. A Na+ Superionic Conductor for Room-Temperature Sodium Batteries

    Science.gov (United States)

    Song, Shufeng; Duong, Hai M.; Korsunsky, Alexander M.; Hu, Ning; Lu, Li

    2016-01-01

    Rechargeable lithium ion batteries have ruled the consumer electronics market for the past 20 years and have great significance in the growing number of electric vehicles and stationary energy storage applications. However, in addition to concerns about electrochemical performance, the limited availability of lithium is gradually becoming an important issue for further continued use and development of lithium ion batteries. Therefore, a significant shift in attention has been taking place towards new types of rechargeable batteries such as sodium-based systems that have low cost. Another important aspect of sodium battery is its potential compatibility with the all-solid-state design where solid electrolyte is used to replace liquid one, leading to simple battery design, long life span, and excellent safety. The key to the success of all-solid-state battery design is the challenge of finding solid electrolytes possessing acceptable high ionic conductivities at room temperature. Herein, we report a novel sodium superionic conductor with NASICON structure, Na3.1Zr1.95Mg0.05Si2PO12 that shows high room-temperature ionic conductivity of 3.5 × 10−3 S cm−1. We also report successful fabrication of a room-temperature solid-state Na-S cell using this conductor. PMID:27572915

  1. Mutual capacitance of liquid conductors in deformable tactile sensing arrays

    International Nuclear Information System (INIS)

    Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arrays of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters

  2. Fully filamentized HTS coated conductor via striation and selective electroplating

    International Nuclear Information System (INIS)

    Highlights: ► Fully-filamentized coated conductor with 13-fold reduction in ac losses. ► Selective electroplating for filamentization of thick copper stabilizer. ► A twofold decrease in ac loss by filamentization of copper stabilizer. ► Absence of appreciable coupling loss contribution from electroplating. -- Abstract: A simple, cost-effective method involving top-down mechanical scribing, oxidation and bottom-up electroplating has been successfully developed to fabricate fully filamentized HTS coated conductors. The copper stabilizer layer is selectively electroplated on the superconducting filaments while the striations remain copper-free due to the formation of a resistive oxide layer in between filaments by oxidation of the striated grooves at elevated temperature in oxygen atmosphere. Magnetization AC loss measurements, performed in a frequency range of 45–500 Hz at 77 K, confirmed the expected N-fold reduction in AC loss of the filamentized tapes with no significant degradation in critical current beyond that due to the material removal from the striations (N – number of filaments). A considerable reduction in coupling AC loss was observed after high temperature annealing/oxidation of the striated tapes. Furthermore, a significant reduction in eddy current loss was achieved with selective copper electroplating, as evidenced by analyzing the field and frequency dependence of magnetization AC loss, as well as by comparing the AC loss performance of striated samples to that of non-striated samples after electroplating of copper stabilizer

  3. Flexural self-damping in overhead electrical transmission conductors

    Science.gov (United States)

    Rawlins, Charles B.

    2009-06-01

    Internal damping of tensioned cables during flexure by transverse vibration is analyzed. The flexure causes relative movements between the wires or strands of the cable, movements which are constrained by friction between them. Under conditions common to vibration of overhead transmission line conductors the friction is great enough to prevent gross sliding. However, there is microslip at the edges of the interstrand contacts, so there is frictional dissipation. In addition, the frictional forces cause shear strains at the contacts with resulting material damping. An analysis is presented that connects the bodily flexure of the conductor with the internal interstrand movements and forces, and with the amounts of dissipation that occur—self-damping. Comparison of estimates based on the analysis with measured data on self-damping reveals reasonable agreement, for a limited range. Cases lying outside that range appear to be associated with treatments applied to cable samples involved in the measurements prior to testing. Possible mechanisms activated by these treatments are discussed.

  4. Mutual capacitance of liquid conductors in deformable tactile sensing arrays

    Science.gov (United States)

    Li, Bin; Fontecchio, Adam K.; Visell, Yon

    2016-01-01

    Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arrays of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters.

  5. Nb3Sn Conductor Development and Characterization for NED

    CERN Document Server

    Boutboul, T; Devred, A; Fabbricatore, P; Greco, M; Leroy, D; Oberli, L; Pedrini, D; Volpini, G

    2008-01-01

    The main purpose of Next European Dipole (NED) project is to design and to build an Nb3Sn ~ 15 T dipole magnet. Due to budget constraints, NED is mainly focused on superconducting cable development and production. In this work, an update is given on the NED conductor development by Alstom-MSA and SMI, which uses, respectively, Internal-Tin-Diffusion and Powder-In-Tube methods, with the aim of reaching a non-copper critical current density of ~ 3000 A/mm2 at 12 T and 4.2 K. Characterization results, including critical current and magnetization data, are presented and discussed, as well, for conductors already developed by both companies for this project. SMI succeeded to produce a strand with 50 µm diameter filaments and with a critical current of ~ 1400 A at 4.2 K and 12 T, corresponding to a non-copper critical current density of ~ 2500 A/mm2. Cabling trials with this strand were successfully carried out at LBNL.

  6. Mutual capacitance of liquid conductors in deformable tactile sensing arrays

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bin [Electrical and Computer Engineering Department, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Fontecchio, Adam K. [Electrical and Computer Engineering and Materials Science and Engineering Departments, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Visell, Yon [Electrical and Computer Engineering Department, Media Arts and Technology, California NanoSystems Institute, University of California, Santa Barbara, California 93106 (United States)

    2016-01-04

    Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arrays of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters.

  7. Interacting Electrodynamics of Short Coherent Conductors in Quantum Circuits

    Science.gov (United States)

    Altimiras, C.; Portier, F.; Joyez, P.

    2016-07-01

    When combining lumped mesoscopic electronic components to form a circuit, quantum fluctuations of electrical quantities lead to a nonlinear electromagnetic interaction between the components, which is generally not understood. The Landauer-Büttiker formalism that is frequently used to describe noninteracting coherent mesoscopic components is not directly suited to describe such circuits since it assumes perfect voltage bias, i.e., the absence of fluctuations. Here, we show that for short coherent conductors of arbitrary transmission, the Landauer-Büttiker formalism can be extended to take into account quantum voltage fluctuations similarly to what is done for tunnel junctions. The electrodynamics of the whole circuit is then formally worked out disregarding the non-Gaussianity of fluctuations. This reveals how the aforementioned nonlinear interaction operates in short coherent conductors: Voltage fluctuations induce a reduction of conductance through the phenomenon of dynamical Coulomb blockade, but they also modify their internal density of states, leading to an additional electrostatic modification of the transmission. Using this approach, we can quantitatively account for conductance measurements performed on quantum point contacts in series with impedances of the order of RK=h /e2 . Our work should enable a better engineering of quantum circuits with targeted properties.

  8. Thin magnetic conductor substrate for placement-immune, electrically-small antennas.

    Energy Technology Data Exchange (ETDEWEB)

    Eubanks, Travis Wayne; McDonald, Jacob J.; Loui, Hung

    2011-09-01

    An antenna is considered to be placement-immune when the antenna operates effectively regardless of where it is placed. By building antennas on magnetic conductor materials, the radiated fields will be positively reinforced in the desired radiation direction instead of being negatively affected by the environment. Although this idea has been discussed thoroughly in theoretical research, the difficulty in building thin magnetic conductor materials necessary for in-phase field reflections prevents this technology from becoming more widespread. This project's purpose is to build and measure an electrically-small antenna on a new type of non-metallic, thin magnetic conductor. This problem has not been previously addressed because non-metallic, thin magnetic conductor materials have not yet been discovered. This work proposed the creation of an artificial magnetic conductor (AMC) with in-phase field reflections without using internal electric conductors, the placement of an electrically-small antenna on this magnetic conductor, and the development of a transmit-receive system that utilizes the substrate and electrically-small antenna. By not using internal electric conductors to create the AMC, the substrate thickness can be minimized. The electrically-small antenna will demonstrate the substrate's ability to make an antenna placement immune, and the transmit-receive system combines both the antenna and the substrate while adding a third layer of system complexity to demonstrate the complete idea.

  9. Homogeneous Current Distribution in Multi-laminated HTS Tape Conductor for Pancake Coil of SMES

    Science.gov (United States)

    Hamajima, T.; Chiba, Y.; Atomura, N.; Takahashi, T.; Miyagi, D.; Tsuda, M.; Shikimachi, K.; Hirano, N.; Nagaya, S.

    A multi-laminated HTS tape conductor has been recently developed to fabricate large pancake coils such as SMES. If the HTS tapes are simply laminated to form the conductor, the current distribution in the laminated tape conductor of the coil is unbalanced because of different inductances of all tapes. The pancake coil has been widely used for large magnet, because the pancake coil is tightly wound and endures large electromagnetic force. The tape transpositions at both ends of the pancake coil are effective for the coil fabrication, because it cannot damage the conductor. It is very important to analyze current distribution in the multi-laminated tape conductor used for the pancake coil. In this paper, we analyze the current distribution in the tape conductor by using circuit model, and then propose a relationship between the laminated tape number of the conductor and the pancake coil number to obtain the homogeneous current distribution. We fabricated the double pancake coil based on the relation, tested it to verify the relation and demonstrated the homogeneous current distribution in the conductor.

  10. Simulation of multiple stability regions in an internally cooled superconducting conductor with the computer code SSICC

    International Nuclear Information System (INIS)

    The computer code SSICC (Safety and Stability of Internally Cooled Conductors) has successfully simulated the multiple stability regions observed experimentally by Lue, Miller, and Dresner of Oak Ridge National Laboratory. The simulation requires asymmetrical boundary conditions and a heating pulse duration short compared to the time for reflection of the transient pressure wave back into the heated region of the conductor

  11. Status of European manufacture of Toroidal Field conductor and strand for JT-60SA project

    International Nuclear Information System (INIS)

    In the framework of the JT-60SA project, part of the Broader Approach (BA) agreement, EURATOM provides to Japan, the Toroidal Field (TF) magnet system, consisting of 18 superconducting coils. The procurement of the conductor for the TF coils is managed by Fusion for Energy, acting as EU representative in the BA agreement. The TF conductor procurement is split into two contracts, one dedicated to the production of Niobium Titanium (NbTi) and Cu strand and the other to TF conductor production through strand cabling and cable jacketing operations. The TF conductor is a rectangular-shaped cable-in-conduit conductor formed by 486 (0.81 mm diameter) strands (2/3 NbTi–1/3 Cu) wrapped in a stainless steel foil and embedded into a stainless steel jacket. The 18 TF coils require (including spares) 115 ‘Unit Lengths’ (UL) of such conductor, each 240 m long for a total of about 28 km. Correspondingly about 10,000 km for NbTi and 5000 km for Cu strand are produced. The Japanese company Furukawa Electric Co. (FEC) is in charge of TF strand manufacture while the Italian company Italian Consortium for Applied Superconductivity (ICAS) is in charge of cabling and jacketing of TF conductor ULs. In the paper, we provide information on the production stages presently achieved in TF strand and conductor contracts

  12. Ceramic to metal attachment system. [Ceramic electrode to metal conductor in MHD generator

    Science.gov (United States)

    Marchant, D.D.

    1983-06-10

    A composition and method are described for attaching a ceramic electrode to a metal conductor. A layer of randomly interlocked metal fibers saturated with polyimide resin is sandwiched between the ceramic electrode and the metal conductor. The polyimide resin is then polymerized providing bonding.

  13. Band gap engineering of MoS2 upon compression

    Science.gov (United States)

    López-Suárez, Miquel; Neri, Igor; Rurali, Riccardo

    2016-04-01

    Molybdenum disulfide (MoS2) is a promising candidate for 2D nanoelectronic devices, which shows a direct band-gap for monolayer structure. In this work we study the electronic structure of MoS2 upon both compressive and tensile strains with first-principles density-functional calculations for different number of layers. The results show that the band-gap can be engineered for experimentally attainable strains (i.e., ±0.15). However, compressive strain can result in bucking that can prevent the use of large compressive strain. We then studied the stability of the compression, calculating the critical strain that results in the on-set of buckling for free-standing nanoribbons of different lengths. The results demonstrate that short structures, or few-layer MoS2, show semi-conductor to metal transition upon compressive strain without bucking.

  14. One-man band

    OpenAIRE

    Stillman, R.

    2013-01-01

    This website presents practice-based research related to solo simultaneous instrumental performance ('one-man band'). The site was conceived as a creative and widely accessible platform for music and ideas resulting from one-man band activates carried out between 2008 and 2013. Central to this project is an interest in how one-man band technique informs compositional process, including studio production. Through presentation and analysis of the author’s own creative practice, the site exp...

  15. AC loss characteristics of simulated CIC-type conductors having plastic conduit

    International Nuclear Information System (INIS)

    When alternating current superconducting coils having cable-in-conduit conductors are fabricated, non-metallic conduit materials are necessary to avoid eddy current losses in the conduits. Using two kinds of non-metallic tapes made of glass fiber reinforced plastics (GFRPs) and Dyneema fiber reinforced plastics (DFRPs), we made the conductors with the GFRP conduits and DFRP conduits, and experimentally studied the total losses of the conductors. The measured results showed that the total loss of the conductor with the GFRP conduit was smaller than that with the DFRP conduit at the same value of the void ratio, the transport current, the external magnetic field, and so on. When the void ratios become high, the superconducting bundle cable can easily move in the conduit. Hence the measured total losses increased with the void ratios of the conductors

  16. Stability and protection of forced cooling conductor for large superconducting magnet

    International Nuclear Information System (INIS)

    From the requirements or needs revealed from the coil design at the conceptual design activity in ITER, the forced flow conductor cooled by supercritical helium is the most suitable. The stability margins against the quench of superconducting coils were measured in a function of magnetic field, operating temperature, and the operating current in several cable-in-conduit conductors of large superconducting magnets. The measured stability margins are analyzed to provide the design criteria of the stability margin of the large current superconducting conductor by using a fluid dynamic analysis, a non-dimensional thermal analysis and a concept of the limiting current. The disturbances inside the superconducting conductor are estimated at duration times and values from several experimental data. The influence of the quench is relatively small if the coil protection works within a few seconds. The hot spot temperature in case of large magnet is estimated from experimental data using a small conductor. (J.P.N.) 140 refs

  17. Magnetic guide of cold atoms using a U-shaped current-carrying conductor

    Institute of Scientific and Technical Information of China (English)

    刘南春; 印建平

    2003-01-01

    We propose a new scheme to magnetically guide cold neutral atoms using a U-shaped current carrying conductor.The spatial magnetic field distribution from the U-shaped current-carrying conductor and the relationship between the magnetic field and parameters of the U-shaped conductor are analysed.Our study shows that U-shaped current-carrying conductor can be used to realize single-or double-channel magnetic guiding of cold atoms in weak-field-seeking states and to construct wrious atom-optical elements.By using Monte Carlo simulations,the dynamic process of the guided atomic-beam splitting in an atomic-beam splitter composed by the U-shaped current-carrying conductor is studied,and some results are presented.

  18. Current distribution and stability of LTS/HTS hybrid superconducting conductors

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2223/Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2223/Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

  19. Electronic Structure of the ID Conductor K0.3MoO3 studied using resonant inelastic x-ray scattering and soft x-ray emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Learmonth, T.; Glans, P.-A.; McGuinness, C.; Plucinski, L.; Zhang, Y.; Guo, J.-H.; Greenblatt, M.; Smith, K.E.

    2008-09-24

    The electronic structure of the quasi-one dimensional conductor K{sub 0.3}MoO{sub 3} has been measured using high resolution resonant inelastic x-ray scattering and x-ray absorption spectroscopy. The data is compared to that from the related two dimensional insulator {alpha}-MoO{sub 3}. Scattering features are observed from both oxides that are explained in terms of the band momentum selectivity of the scattering process, allowing a comparison of the scattering data to recent band structure calculations.

  20. Transparent rectifying contacts on wide-band gap oxide semiconductors

    OpenAIRE

    Lajn, Alexander

    2013-01-01

    Die vorliegenden Arbeit befasst sich mit der Herstellung und Charakterisierung von transparenten Metall-Halbleiter- Feldeffekttransistoren. Dazu werden im ersten Kapitel transparente gleichrichtende Kontakte, basierend auf dem Konzept von Metalloxidkontakten, hergestellt und im Hinblick auf chemische Zusammensetzung des Kontaktmaterials, Barriereninhomogenität und Kompatibilität mit amorphen Halbleitern untersucht. Außerdem wird die Anwendbarkeit der Kontakte als UV-Sensor studiert. I...

  1. AC magnetization losses in striated YBCO-123/Hastelloy coated conductors

    International Nuclear Information System (INIS)

    In this work we present experimental results of reductions in AC magnetization losses due to a striation process in YBCO-123/Hastelloy coated conductors. The measurements were carried out in a sinusoidally varying external magnetic field, with amplitudes up to 100 mT, in a frequency range of 8.5-85.4 Hz, and at a temperature of 77 K. The field was oriented perpendicularly to the face of the tapes. Sample tapes were successively patterned into the form of narrow parallel strips, by means of a photoresist lithography and chemical wet etching technique. Experimental results are discussed in the framework of existing theoretical models for energy dissipation in thin films in perpendicular AC magnetic fields

  2. OPG operational experience with stator conductor bars fouling

    International Nuclear Information System (INIS)

    Over the last three years, Ontario Power Generation (OPG) Pickering Nuclear has experienced fouling of the stator conductor bar cooling water channels on two units. To address the associated stator bar temperature rises, chemical cleaning was undertaken three times on one unit and once on the other. These events were the subject of two formal investigations and a single rigorous chemistry assessment. The investigations were conducted using a formalized root-cause protocol. The assessment involved a system chemistry review over a 10-year period and a critical evaluation of dissolved oxygen control. This paper describes: - the internal investigations undertaken by OPG to better understand and resolve the problem, - OPG's cleaning strategy and different cleaning options performed on affected units, - the remedial actions undertaken by OPG, and - The interim actions following the final post-cleaning inspections. (orig.)

  3. Effect of annular secondary conductor in a linear electromagnetic stirrer

    Indian Academy of Sciences (India)

    R Madhavan; V Ramanarayanan

    2008-10-01

    This paper presents the variation of average axial force density in the annular secondary conductor of a linear electromagnetic stirrer. Different geometries of secondaries are considered for numerical and experimental validation namely, 1. hollow annular ring, 2. annular ring with a solid cylinder and 3. solid cylinder. Experimental and numerical simulations are performed for a 2-pole in house built 15 kW linear electromagnetic stirrer (EMS). It is observed for a supply current of 200 A at 30 Hz the force densities in the hollow annular ring is 67% higher than the equivalent solid cylinder. The same values are 33% for annular ring with a solid cylinder. Force density variation with supply frequency and current are also reported. Numerical simulations using finite element model are validated with experimental results.

  4. Fuel-Cell Electrolytes Based on Organosilica Hybrid Proton Conductors

    Science.gov (United States)

    Narayan, Sri R.; Yen, Shiao-Pin S.

    2008-01-01

    A new membrane composite material that combines an organosilica proton conductor with perfluorinated Nafion material to achieve good proton conductivity and high-temperature performance for membranes used for fuel cells in stationary, transportation, and portable applications has been developed. To achieve high proton conductivities of the order of 10(exp -1)S/cm over a wide range of temperatures, a composite membrane based on a new class of mesoporous, proton-conducting, hydrogen-bonded organosilica, used with Nafion, will allow for water retention and high proton conductivity over a wider range of temperatures than currently offered by Nafion alone. At the time of this reporting, this innovation is at the concept level. Some of the materials and processes investigated have shown good proton conductivity, but membranes have not yet been prepared and demonstrated.

  5. Magnetism and electronic transport in irradiated organic conductors

    International Nuclear Information System (INIS)

    Quasi-one-dimensional conductors are metallic in a large temperature range. The electronic gas instability can drive a phase transition at low temperature. In one-dimensional conditions, precursor fluctuations grow in the high temperature regime and can give a collective current transport. Under irradiation the quasi-one-dimensional electrons are localized and the conductivity becomes typical of a phonon assisted tunneling between metallic particles. In this study we describe the magnetism of this localized electrons. This disorder reduces the interaction between electronic spins and phonons and favours the interaction between localized spins. But if the electronic gas is less one-dimensional, irradiation disorder can not localize electrons. Our conductivity measurements prove that the disorder first reduces the electronic relaxation before induces the above mentioned localization. Moreover the fluctuative conductivity is revealed by irradiation thanks to a discrepancy with respect to one-electron model. TTF-TCNQ and (TMTSF)2ClO4 are investigated in that way

  6. Diamagnetic phase transitions in two-dimensional conductors

    Energy Technology Data Exchange (ETDEWEB)

    Bakaleinikov, L.A., E-mail: bakal.ammp@mail.ioffe.ru [A.F. Ioffe Physico-Technical Institute, Russian Academy of Sciences, St. Petersburg 194021 (Russian Federation); Department of Mathematics and Physics, Faculty of Natural Sciences, University of Haifa, Campus Oranim, Tivon 36006 (Israel); Gordon, A. [Department of Mathematics and Physics, Faculty of Natural Sciences, University of Haifa, Campus Oranim, Tivon 36006 (Israel)

    2014-11-15

    A theory describing the susceptibility amplitude and the magnetic induction bifurcation near the dHvA driven diamagnetic phase transitions in quasi two-dimensional (2D) organic conductors of the (ET){sub 2}X with X=Cu(NCS){sub 2},KHg(SCN){sub 4},I{sub 3},AuBr{sub 2},IBr{sub 2}, etc. is presented. We show that there is a drastic increase in the temperature and magnetic field dependence of the susceptibility amplitude on approaching the diamagnetic phase transition point. Near the phase transition point the temperature and magnetic field dependences are fitted by the ones typical of the mean-field phase transition theory. These dependences confirm the long-range character of the magnetic interactions among the conduction electrons leading to diamagnetic phase transitions. We demonstrate that the magnetic induction splitting of nuclear magnetic resonance (NMR) and muon spin-rotation spectroscopy (μSR) lines due to two Condon domains decreases tending to zero on approaching the diamagnetic phase transition. This decrease is fitted by the temperature and magnetic field dependence of the susceptibility characteristic of the mean-field theory of phase transitions. Performing new susceptibility, NMR and μSR experiments will enable to detect diamagnetic phase transitions and Condon domains in quasi 2D metals. - Highlights: • A theory of diamagnetic phase transitions (DPTs) is presented in 2D organic conductors. • The behaviour of the susceptibility amplitude and the induction splitting is shown near the DPT. • The calculated quantities are described by the mean-field theory of phase transitions.

  7. A Compensation Method of Conductor Parameter for Transient Fault Location

    Science.gov (United States)

    Ugbome, Chukwunweike Lucky

    Faults in underground distribution systems are predominantly caused by the deterioration of cable insulation. The inherent nature of underground distribution is such that cables are laid underground and exposed to harmful substances which can cause deterioration of cable insulation. The penetration of water into the cable splice is a common cause of cable deterioration and a common source of transitory sub-cycle cable fault in underground distribution systems. The presence of a sub-cycle fault in a distribution line is not necessarily noticeable and may not cause any protective device to operate due to its short live-span but can be destructive if it is sustained and unattended to. The location of transitory sub-cycle fault in underground cable is fundamentally important in preventing and containing a permanent fault which can potentially result to an unplanned outage. However the location of this type of fault is not easy due to so many unknowns. A few numbers of approaches have been developed for determining the location of short-lived sub-cycle (SLSC) faults, but they approximate the conductor parameter which would reduce the accuracy of the location determination. This thesis develops an algorithm for transitory sub-cycle fault location to compensate for the ignored conductor parameter by employing the X/R ratio of the distribution line. First, a model for transient faults at different locations in underground cable is presented and used to generate the voltage and current waveforms at the source side. Also presented is the performance of the fault location by the uncompensated and compensated algorithms under two configurations of the distribution line: a homogeneous distribution circuit and a heterogeneous distribution line. The result obtained from the performance studies show that the proposed compensation method would help the non-compensated fault location approaches to achieve relatively high accuracy in locating transitory sub-cycle faults in numerous

  8. Actitudes hacia comportamientos protectores y de riesgo en conductores costarricenses

    Directory of Open Access Journals (Sweden)

    Marjorie Moreno Salas

    2011-12-01

    Full Text Available En el presente estudio se exploraron las actitudes y los comportamientos protectores y de riesgo al conducir vehículos particulares en una muestra de 590 conductores de entre 20 y 60 años (M = 38,57, DE =11,69 residentes del área metropolitana costarricense. Se realizó una investigación exploratoria, desarrollada mediante un diseño transversal con un cuestionario autoaplicado. Los principales resultados fueron que: A mayor cantidad de hijos e hijas dependientes, menores comportamientos y actitudes hacia el riesgo y mayores comportamientos protectores. A mayor cantidad de años de tener licencia, menores actitudes hacia el exceso de velocidad y menores comportamientos de riesgo asociados con la alta velocidad. Entre más días de manejo, mayores comportamientos protectores. A mayor reporte de actitudes y comportamientos favorables hacia el riesgo, menor edad de los participantes. A manera de conclusión, las actitudes y los comportamientos de riesgo se vinculan negativamente. Además, variables sociodemográficas como el número de hijos y la edad de los conductores modula la respuesta en cuanto a las actitudes y los comportamientos protectores y de riesgo al manejar. Los resultados del estudio forman un primer aporte a la investigación nacional en el tema, en tanto, se cuenta con un instrumento susceptible de ser aplicado en otros estudios y múltiples datos empíricos en la temática.

  9. Development of 1 m HTS conductor using YBCO on textured metal substrate

    International Nuclear Information System (INIS)

    We fabricated 1 m high temperature superconducting conductor (HTS conductor) using YBa2Cu3O7-x coated conductors (YBCO tapes) on textured metal substrates, which are expected to be lower in cost than YBCO tapes using ion-beam assisted deposition. Those substrate and intermediate layers were manufactured by Furukawa Electric, and YBCO and a protective layer were applied to the intermediate layer by Chubu Electric Power. Before fabricating the conductor, a 0.1 mm thick copper tape was soldered to the YBCO tape, and 10 mm wide YBCO tape was divided into three strips by a YAG laser. To have sufficient current capacity for 1 kA, a two-layer conductor was fabricated, and its critical current (Ic) was 1976 A, but the magnetic properties of the textured metal substrates affected the increase in AC loss. In a low current region, the AC loss in this conductor was much higher than the Norris strip model, but approached the Norris strip model in the high current region because the magnetization was almost saturated. Low AC loss of 0.144 W/m at 1 kArms was achieved even though the conductor had a small outer diameter of 20 mm and was composed of YBCO tapes with magnetic substrates.

  10. Development of 1 m HTS conductor using YBCO on textured metal substrate

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, M., E-mail: m-yagi@ch.furukawa.co.j [Furukawa Electric Co., Ltd, 6, Yawata-Kaigandori, Ichihara, Chiba 290-8555 (Japan); Sakamoto, H. [Furukawa Electric Co., Ltd, 500, Kiyotaki-machi, Nikko, Tochigi 321-1493 (Japan); Mukoyama, S. [Furukawa Electric Co., Ltd, 6, Yawata-Kaigandori, Ichihara, Chiba 290-8555 (Japan); Yamamoto, K. [Furukawa Electric Co., Ltd, 500, Kiyotaki-machi, Nikko, Tochigi 321-1493 (Japan); Amemiya, N. [Kyoto University, Kyotodaigaku-Katsura, Nishikyo, Kyoto 615-8510 (Japan); Nagaya, S.; Kashima, N. [Chubu Electric Power Co., Inc., 20-1, Kitasekiyama, Ohdaka-cho, Midori-ku, Nagoya 459-8522 (Japan); Shiohara, Y. [Superconductivity Research Laboratory, 1-10-13, Shinonome, Koto-ku, Tokyo 135-0062 (Japan)

    2009-10-15

    We fabricated 1 m high temperature superconducting conductor (HTS conductor) using YBa{sub 2}Cu{sub 3}O{sub 7-x} coated conductors (YBCO tapes) on textured metal substrates, which are expected to be lower in cost than YBCO tapes using ion-beam assisted deposition. Those substrate and intermediate layers were manufactured by Furukawa Electric, and YBCO and a protective layer were applied to the intermediate layer by Chubu Electric Power. Before fabricating the conductor, a 0.1 mm thick copper tape was soldered to the YBCO tape, and 10 mm wide YBCO tape was divided into three strips by a YAG laser. To have sufficient current capacity for 1 kA, a two-layer conductor was fabricated, and its critical current (I{sub c}) was 1976 A, but the magnetic properties of the textured metal substrates affected the increase in AC loss. In a low current region, the AC loss in this conductor was much higher than the Norris strip model, but approached the Norris strip model in the high current region because the magnetization was almost saturated. Low AC loss of 0.144 W/m at 1 kA{sub rms} was achieved even though the conductor had a small outer diameter of 20 mm and was composed of YBCO tapes with magnetic substrates.

  11. Electrohydrodynamic direct—writing of conductor—insulator-conductor multi-layer interconnection

    International Nuclear Information System (INIS)

    A multi-layer interconnection structure is a basic component of electronic devices, and printing of the multi-layer interconnection structure is the key process in printed electronics. In this work, electrohydrodynamic direct-writing (EDW) is utilized to print the conductor—insulator—conductor multi-layer interconnection structure. Silver ink is chosen to print the conductor pattern, and a polyvinylpyrrolidone (PVP) solution is utilized to fabricate the insulator layer between the bottom and top conductor patterns. The influences of EDW process parameters on the line width of the printed conductor and insulator patterns are studied systematically. The obtained results show that the line width of the printed structure increases with the increase of the flow rate, but decreases with the increase of applied voltage and PVP content in the solution. The average resistivity values of the bottom and top silver conductor tracks are determined to be 1.34 × 10−7 Ω·m and 1.39 × 10−7 Ω·m, respectively. The printed PVP layer between the two conductor tracks is well insulated, which can meet the insulation requirement of the electronic devices. This study offers an alternative, fast, and cost-effective method of fabricating conductor—insulator—conductor multi-layer interconnections in the electronic industry

  12. Stress dependence of the critical currents in neutron irradiated (RE)BCO coated conductors

    International Nuclear Information System (INIS)

    The application of HTS coated conductors in future fusion or accelerator magnets is currently of increasing interest. High Lorentz forces and therefore high hoop stresses act on the conductors in large coils. The conductor is furthermore exposed to neutron radiation in fusion or accelerator magnets. The expected neutron fluence over the desired lifetime of such magnets can be simulated by irradiation experiments in a fission reactor. The coated conductors were characterized in the pristine state and after irradiation to a fast neutron fluence of 1 × 1022 m−2 (ITER design fluence). The sensitivity of the critical currents to applied stress was measured in liquid nitrogen. The cold part of the setup was positioned within a rotatable split coil electro-magnet to assess the Ic-anisotropy up to 1.4 T under maximum Lorentz force configuration. The Ic-sensitivity to applied stress changed significantly in the GdBCO/IBAD conductor after irradiation, whereas nearly no change was observed in the YBCO/RABiTS conductor. Furthermore, Ic and Tc were strongly reduced in the GdBCO/IBAD sample after irradiation. The angular dependence of Ic changed for both samples in different ways after the irradiation, but no change in the angular dependence was observed upon applying stress. The high neutron capture cross-section of Gd and the resulting strong reduction of Tc seem to be responsible for the different stress dependences of Ic in irradiated Gd-123 coated conductors. (paper)

  13. Electrohydrodynamic direct—writing of conductor—insulator-conductor multi-layer interconnection

    Science.gov (United States)

    Zheng, Gao-Feng; Pei, Yan-Bo; Wang, Xiang; Zheng, Jian-Yi; Sun, Dao-Heng

    2014-06-01

    A multi-layer interconnection structure is a basic component of electronic devices, and printing of the multi-layer interconnection structure is the key process in printed electronics. In this work, electrohydrodynamic direct-writing (EDW) is utilized to print the conductor—insulator—conductor multi-layer interconnection structure. Silver ink is chosen to print the conductor pattern, and a polyvinylpyrrolidone (PVP) solution is utilized to fabricate the insulator layer between the bottom and top conductor patterns. The influences of EDW process parameters on the line width of the printed conductor and insulator patterns are studied systematically. The obtained results show that the line width of the printed structure increases with the increase of the flow rate, but decreases with the increase of applied voltage and PVP content in the solution. The average resistivity values of the bottom and top silver conductor tracks are determined to be 1.34 × 10-7 Ω·m and 1.39 × 10-7 Ω·m, respectively. The printed PVP layer between the two conductor tracks is well insulated, which can meet the insulation requirement of the electronic devices. This study offers an alternative, fast, and cost-effective method of fabricating conductor—insulator—conductor multi-layer interconnections in the electronic industry.

  14. A 50 mm BORE, 13 TESLA SUPERCONDUCTING MAGNET EMPLOYING A PREREACTED MULTIFILAMENTARY Nb3Sn CONDUCTOR

    OpenAIRE

    Noto, K.; Watanabe, K; Muto, Y; M. Ikeda; Tanaka, Y.; Inoue, I; Ban, M

    1984-01-01

    Following the construction of two hybrid magnets, we intend to build up a third hybrid magnet which will produce about 30 T. A prereacted multifilamentary Nb3Sn conductor will be employed for the 12 T superconducting part of the hybrid. As a first step for the project, we have designed, constructed and tested a magnet which consists of 14 double-pancakes made of a prereacted multifilamentary Nb3Sn conductor and a back up coil made of a Nb-Ti conductor. The satisfactory results of the test on ...

  15. Modeling the electrical resistance of gold film conductors on uniaxially stretched elastomeric substrates

    Science.gov (United States)

    Cao, Wenzhe; Görrn, Patrick; Wagner, Sigurd

    2011-05-01

    The electrical resistance of gold film conductors on polydimethyl siloxane substrates at stages of uniaxial stretching is measured and modeled. The surface area of a gold conductor is assumed constant during stretching so that the exposed substrate takes up all strain. Sheet resistances are calculated from frames of scanning electron micrographs by numerically solving for the electrical potentials of all pixels in a frame. These sheet resistances agree sufficiently well with values measured on the same conductors to give credence to the model of a stretchable network of gold links defined by microcracks.

  16. Effect of bending on critical current of react-and-jacket processed Nb3Sn conductor

    International Nuclear Information System (INIS)

    A 'react-and-jacket' processed Nb3Sn conductor consisting of a Rutherford cable and aluminum-alloy jacket has been developed for large-scale magnets. This study investigates the effect of bending on the critical current of this conductor, which has a cross-section of 17 x 4.9 mm2. The conductor was wound in a three-turn coil and its critical current was measured. The measured critical currents can be fitted by an empirical formula that gives the strain dependence. (author)

  17. Fabrication and modeling of stretchable conductors for traumatic brain injury research

    Science.gov (United States)

    Cao, Wenzhe

    Stretchable electronics are an emergent class of electronics that can retain their electric functionality under large mechanical deformation, such as stretching, bending and compression. Like traditional electric circuits, stretchable electronics rely on electrical conductors, but in this specific instance the conductors must also be stretchable. This thesis research had three goals: (1) fabricate elastically stretchable conductors that retain their electrical conductance when stretched by tens of percent of strain; (2) understand the underlying stretching mechanism of gold conductors on polydimethylsiloxane (PDMS) substrates; (3) produce a special device---a stretchable microelectrode array, which contains a matrix of stretchable conductors that enables a new approach to studying traumatic brain injury. We first developed and optimized the micro-fabrication process to make elastically stretchable thin gold film conductors on PDMS substrates. The conductors can retain electrical conduction while being stretched reversibly to 140% uniaxially and 16% radially. We further developed a fabrication process to encapsulate the conductors with either a commercially available photopatternable silicone (PPS) or with PDMS. 100 microm by 100 microm vias were patterned in the encapsulation layer to expose electrical contacts. PPS encapsulated conductors can be stretched uniaxially to 80%, and the PDMS encapsulated conductor can be stretched to ˜15%, without losing electrical conduction. We also introduced acrylate-based shape memory polymers (SMPs) as a new type of substrate for stretchable conductors. Their stiffness can be tuned by varying the monomer composition or by changing the ambient temperature. Thin gold film conductors deposited on pre-strained SMPs remain conductive when first stretched and then relaxed to their pre-strain value. Moreover, an SMP can also serve as a stretchable carrier to make pre-strained conductors on an overlying PDMS membrane. The resistance of

  18. Grondwaterbemonstering vanuit een analytisch-chemisch perspectief

    NARCIS (Netherlands)

    Velde-Koerts T van der; LAC

    2000-01-01

    A national monitoring network was set up to inventory the quality of the upper ground water under farms. The aim was to investigate if the sampling procedure developed for nutrient analysis, would also be suitable for metal analysis. Leaching and sorption of metals during sampling was due mainly to

  19. Beschichtung von Kohlenstofffasern durch Chemische Gasphasenabscheidung (CVD)

    OpenAIRE

    Schmidt, Stephan

    2005-01-01

    Der Einsatz faserverstärkter Verbundwerkstoffe mit metallischer und keramischer Matrix bietet den Vorteil von Kombination und optimaler Ausnutzung verschiedenster Werkstoffeigenschaften. Die Verwendung einer durch Kohlenstofffasern verstärkten keramischen Matrix erlangte dabei in der kürzeren Vergangenheit vermehrtes Interesse. Grundlegend für den erfolgreichen Einsatz von Faserverbundwerkstoffen ist dabei ein optimiertes Faser-Matrix-Interface, also eine "optimale" Haftung der Fasern innerha...

  20. Onderzoek naar de chemische samenstelling van lekkerbekjes

    NARCIS (Netherlands)

    Cazemier, G.; Jong, de J.; Herstel, H.

    1990-01-01

    In oktober 1988 werden 40 monsters lekkerbekjes onderzocht op de gehalten aan vocht, vet, eiwit, zetmeel , fosfaat en chloride, vier van de monsters werden getest op de aanwezigheid van polyfosfaten. Daarnaast werden van alle lekkerbekjes de stuksgewichten bepaald, die bleken uiteen te lopen van L17

  1. Chemische laboratoria in de negentiende eeuw

    OpenAIRE

    H.A.M. Snelders

    1986-01-01

    Nineteenth-century chemical laboratories in the Netherlands

    By the Royal Decree of 1815 a separate faculty of mathematics and natural science was founded at the Dutch universities of Leyden, Utrecht and Groningen. The decree emphatically stated that each of those universities should have a chemical laboratory. The teaching of chemistry was , however, of little significance. This situation changed radically when G.J. Mulder was appointed professor o...

  2. Chemische laboratoria in de negentiende eeuw

    Directory of Open Access Journals (Sweden)

    H.A.M. Snelders

    1986-10-01

    Full Text Available Nineteenth-century chemical laboratories in the Netherlands

    By the Royal Decree of 1815 a separate faculty of mathematics and natural science was founded at the Dutch universities of Leyden, Utrecht and Groningen. The decree emphatically stated that each of those universities should have a chemical laboratory. The teaching of chemistry was , however, of little significance. This situation changed radically when G.J. Mulder was appointed professor of chemistry at Utrecht University (1840. Mulder's ideal was to give his students a practical chemical education; for that purpose he needed an adequate laboratory which he got in 1845. With Mulder and his students a new era of chemical education at Dutch universities began.
    Opportunities for a chemical career were improved by the foundation of a new type of secondary school in 1863, which needed a great number of chemistry teachers. Twelve out of 36 graduate students of J.H. van 't Hoff made a career in governmental services or in private and industrial laboratories. In this article a survey is given of types of non-university laboratories existing in the Netherlands at the end of the last century: private chemical laboratories for the training of chemists outside the university and for the analysis of chemical products; governmental chemical laboratories (sugar, foods; industrial chemical laboratories (the N.V. Nederlandsche Gist- en Spiritusfabriek in Delft appointed a research chemist already in 1885, agricultural chemical laboratories and chemical laboratories at secondary schools where a number of teachers did their own chemical research. With the great expansion of Dutch chemical industry in the beginning of the twentieth century, more and more chemists found a job at the newly established industrial research laboratories

  3. Laparoscopic gastric banding

    Science.gov (United States)

    ... make the band tighter or looser any time after you have this surgery. It may be tightened or ... Having problems eating Not losing enough weight Vomiting after you eat Outlook (Prognosis) The final weight loss with ...

  4. CSF oligoclonal banding - slideshow

    Science.gov (United States)

    ... presentations/100145.htm CSF oligoclonal banding - series—Normal anatomy ... Overview The cerebrospinal fluid (CSF) serves to supply nutrients to the central nervous system (CNS) and collect waste products, as well as ...

  5. The Band Pass Filter

    OpenAIRE

    Christiano, Lawrence J.; Terry J. Fitzgerald

    1999-01-01

    The `ideal' band pass filter can be used to isolate the component of a time series that lies within a particular band of frequencies. However, applying this filter requires a dataset of infinite length. In practice, some sort of approximation is needed. Using projections, we derive approximations that are optimal when the time series representations underlying the raw data have a unit root, or are stationary about a trend. We identify one approximation which, though it is only optimal for one...

  6. Iliotibial band friction syndrome

    OpenAIRE

    Lavine, Ronald

    2010-01-01

    Published articles on iliotibial band friction syndrome have been reviewed. These articles cover the epidemiology, etiology, anatomy, pathology, prevention, and treatment of the condition. This article describes (1) the various etiological models that have been proposed to explain iliotibial band friction syndrome; (2) some of the imaging methods, research studies, and clinical experiences that support or call into question these various models; (3) commonly proposed treatment methods for ili...

  7. Electronic properties close to Dirac cone in two-dimensional organic conductor α-(BEDT-TTF)2I3

    Science.gov (United States)

    Katayama, S.; Kobayashi, A.; Suzumura, Y.

    2009-01-01

    A zero-gap state (ZGS) has been found in a bulk system of two-dimensional organic conductor, α-(BEDT-TTF)2I3 salt which consists of four sites of donor molecules in a unit cell. In the present paper, the characteristic of the ZGS is analyzed in detail and the electronic properties are examined in the vicinity of the Dirac point where the conduction and valence bands degenerate to form the zero-gap. The eigenvectors of the energy band have four components of respective sites, where two of them correspond to inequivalent sites and the other two correspond to equivalent sites. It is shown that the former exhibits an exotic momentum dependence around the contact point and the latter shows almost a constant dependence. The density of states of each site close to the Dirac point is calculated to demonstrate the temperature dependence of the local magnetic susceptibility and the local nuclear magnetic relaxation rate. Further, the robust property of the ZGS against the anion potential is also shown by using the second-order perturbation.

  8. Homogeneous current distribution experiment in a multi-laminated HTS tape conductor for a double-pancake coil of SMES

    Energy Technology Data Exchange (ETDEWEB)

    Atomura, N., E-mail: a.naoki@ecei.tohoku.ac.jp [Electrical Engineering Department, Graduate School, Tohoku University, 6-6-05 Aoba Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Takahashi, T.; Chiba, Y.; Tsuda, M.; Hamajima, T. [Electrical Engineering Department, Graduate School, Tohoku University, 6-6-05 Aoba Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Shikimachi, K.; Hirano, N.; Nagaya, S. [Chubu Electric Power Co., Inc., 1, Higashi-shincho, Higashi-ku, Nagoya 461-8680 (Japan)

    2011-11-15

    We propose a new method to control the current distribution in the laminated conductor. It's using transposition at the innermost layer of a double-pancake coil and adjusting the gaps between the laminated tapes. We design and examine a homogeneous current distribution coil wound with the multi-laminated (four times) HTS tape conductor. The multi-laminated conductor of a double-pancake coil can make the homogeneous current distribution. A multi-laminated HTS tape conductor wound into double-pancake coils has recently been used for large SMES. If the HTS tapes are simply laminated to form the conductor, the current distribution in the laminated tape conductor of the coil is not homogeneous because of the differences among all the tape inductances. Transposition of these tapes at the innermost or outermost layer of the coil is effective for homogeneous current distribution. However, this method would requires the same number of single-pancake coils as that of the HTS tape conductor, and hence the number of HTS tape conductors is restricted. In this paper, we propose a new method to control the current distribution in the laminated conductor using transposition at the innermost layer of a double-pancake coil and adjusting the gaps between the laminated tapes. We analyze the current distributions for multi-laminated HTS tape conductors for a double-pancake coil, and show the homogeneous current distribution of the laminated tape conductor. In order to verify the theory, we designed homogeneous current distribution coil wound with the multi-laminated (four times) HTS tape conductors by transposing them at the innermost layer and by adjusting the additional thickness 0.075 mm between the parallel conductors. We obtained the homogeneous current distribution in the tape conductor. The experimental data were in good agreement with the theory.

  9. Enhanced Mixed Electronic-Ionic Conductors through Cation Ordering

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, Allan J. [Univ. of Houston, TX (United States); Morgan, Dane [Univ. of Wisconsin, Madison, WI (United States); Grey, Clare [Stony Brook Univ., NY (United States)

    2014-08-31

    The performance of many energy conversion and storage devices depend on the properties of mixed ionic-electronic conducting (miec) materials. Mixed or ambipolar conductors simultaneously transport ions and electrons and provide the critical interface between chemical and electrical energy in devices such as fuel cells, ion transport membranes, and batteries. Enhancements in storage capacity, reversibility, power density and device lifetime all require new materials and a better understanding of the fundamentals of ambipolar conductivity and surface reactivity.The high temperature properties of the ordered perovksites AA’B2O5+x, where A = rare earth ion, Y and B = Ba, Sr were studied. The work was motivated by the high oxygen transport and surface exchange rates observed for members of this class of mixed ionic and electronic conductors. A combined experimental and computational approach, including structural, electrochemical, and transport characterization and modeling was used. The approach attacks the problem simultaneously at global (e.g., neutron diffraction and impedance spectroscopy), local (e.g., pair distribution function, nuclear magnetic resonance) and molecular (ab initio thermokinetic modeling) length scales. The objectives of the work were to understand how the cation and associated anion order lead to exceptional ionic and electronic transport properties and surface reactivity in AA’B2O5+x perovskites. A variety of compounds were studied by X-ray and neutron diffraction, measurements of thermodynamics and transport and theoretically. These included PrBaCo2O5+x and NdBaCo2O5+x, PrBaCo2-xFexO6- δ (x = 0, 0.5, 1.0, 1.5 and 2) and LnBaCoFeO6- δ (Ln = La, Pr, Nd, Sm, Eu and Gd), Sr3YCo4O10.5, YBaMn2O5+x. A0.5A’0.5BO3 (where A=Y, Sc, La, Ce, Pr, Nd, Pm, Sm; A’= Sr

  10. Self-healing effect in strained multifilamentary Nb3Sn conductors

    International Nuclear Information System (INIS)

    Multifilamentary Nb3Sn conductors can be strained without damage much more than can bare Nb3Sn. The reason is a compression of the Nb3Sn filaments, which acts as a mechanical reserve, caused by a stronger thermal contraction of the bronze in the composite. By overloading the conductor at low temperature the compression of the Nb3Sn disappears. Afterwards the conductor is subject to damage upon further loading. Measurements of the critical current under strain showed that at least part of the compressive strain can be regained by warming the conductor to room temperature. Analysis of the measured low temperature stress-strain diagram revealed that plastic deformation of the bronze during warming up is the cause of this self-healing. (author)

  11. Stress-tuned conductor-polymer composite for use in sensors

    Science.gov (United States)

    Martin, James E; Read, Douglas H

    2013-10-22

    A method for making a composite polymeric material with electrical conductivity determined by stress-tuning of the conductor-polymer composite, and sensors made with the stress-tuned conductor-polymer composite made by this method. Stress tuning is achieved by mixing a miscible liquid into the polymer precursor solution or by absorbing into the precursor solution a soluble compound from vapor in contact with the polymer precursor solution. The conductor may or may not be ordered by application of a magnetic field. The composite is formed by polymerization with the stress-tuning agent in the polymer matrix. The stress-tuning agent is removed following polymerization to produce a conductor-polymer composite with a stress field that depends on the amount of stress-tuning agent employed.

  12. Test results of the ITER PF insert conductor short sample in SULTAN

    International Nuclear Information System (INIS)

    A short sample of the NbTi cable-in-conduit conductor (CICC) manufactured for the ITER PF insert coil has been tested in the SULTAN facility at CRPP. The short sample consists of two paired conductor sections, identical except for the sub-cable and outer wraps, which have been removed from one of the sections before jacketing. The test program for conductor and joint includes DC performance, cyclic load and AC loss, with a large number of voltage taps and Hall sensors for current distribution. At high operating current, the DC behavior is well below expectations, with temperature margin lower than specified in the ITER design criteria. The conductor without wraps has higher tolerance to current unbalance. The joint resistance is by far higher than targeted. (authors)

  13. Transient Thermal Analysis of Intense Proton Beam Loss on a Kicker Magnet Conductor Plate

    CERN Document Server

    Knaus, P

    2000-01-01

    The Super Proton Synchrotron SPS will be used as injector for the Large Hadron Collider LHC and needs adaptation to meet LHC requirements. The SPS injection kicker magnets MKP will undergo important modifications to comply with the requirements on magnetic field rise-time and ripple. The injection kicker presently installed has a return conductor of beryllium to minimise the risk of metal evaporation from its surface due to heating caused by beam impact. In the context of refurbishing the MKP to satisfy LHC requirements these conductors need replacement, preferably with a less delicate material. This article presents the transient thermal analysis of energy deposition caused by beam loss on the conductor plate. The expected time structure of the beam is taken into account. Simulations comparing different conductor materials have been performed, leading to the result that a significantly cheaper and fully inoffensive titanium alloy can satisfy the needs.

  14. Tester automatically checks insulation of individual conductors in multiple-strand cables

    Science.gov (United States)

    Shaw, J.; Vuckovich, M.

    1967-01-01

    Insulation tester checks multiple-strand electrical cables in nuclear rocket reactors. It has both manual and automatic capabilities and can check the insulation of a cable with 200 or more conductors in a few minutes.

  15. Simple method for high-performance stretchable composite conductors with entrapped air bubbles.

    Science.gov (United States)

    Hwang, Hyejin; Kim, Dae-Gon; Jang, Nam-Su; Kong, Jeong-Ho; Kim, Jong-Man

    2016-12-01

    We integrate air bubbles into conductive elastic composite-based stretchable conductors to make them mechanically less stiff and electrically more robust against physical deformations. A surfactant facilitates both the formation and maintenance of air bubbles inside the elastic composites, leading to a simple fabrication of bubble-entrapped stretchable conductors. Based on the unique bubble-entrapped architecture, the elastic properties are greatly enhanced and the resistance change in response to tensile strains can clearly be controlled. The bubble-entrapped conductor achieves ~80 % elongation at ~3.4 times lower stress and ~44.8 % smaller change in the electrical resistance at 80 % tensile strain, compared to bare conductor without air bubbles. PMID:26754940

  16. Quantitative impedance analysis of solid ionic conductors: Effects of electrode polarization

    Czech Academy of Sciences Publication Activity Database

    Patil, D.; Shimakawa, K.; Zima, Vítězslav; Wágner, T.

    2014-01-01

    Roč. 115, č. 14 (2014), "143707-1"-"143707-6". ISSN 0021-8979 Institutional support: RVO:61389013 Keywords : impedance * conductivity * ion conductors Subject RIV: CA - Inorganic Chemistry Impact factor: 2.183, year: 2014

  17. Health effects of electromagnetic field generated by lightning current pulses near down conductors

    International Nuclear Information System (INIS)

    The lightning current generates a time varying magnetic field near down conductors, when lightning strikes the connected Franklin-rod. The down conductors are mounted on the wall of buildings, where residential places can be situated. It is well known that the rapidly changing magnetic fields could generate dangerous eddy currents in the human body. If the duration and the gradient of the magnetic field were high enough, the peripheral nerves are excited. In this study, the authors introduce an improved model of the interaction of electromagnetic fields of lighting current near a down conductor with the human body. The interaction model has two parts: estimation of the magnetic fields surrounding the down conductor and evaluation of health effects of rapid changing magnetic fields on the human body.

  18. On the electrostatic equilibrium of charges and cavities in a conductor

    CERN Document Server

    Pathak, Aritro

    2016-01-01

    We consider a charged conductor of arbitrary shape, in electrostatic equilibrium, with one or more cavities inside it, and with fixed charges placed outside the conductors and inside the cavities. The field inside a particular cavity is then only due to charges within that cavity itself and to the surface charge induced on the surface of the same cavity. A similar statement holds for the exterior of the conductor. Although this is an elementary property of conductors, it is not a trivial statement, as explained in this article. Undergraduate texts in electrodynamics do not discuss at length or provide a complete argument for an important problem such as this. Two simple and complete proofs are provided in this note with the help of the standard electrostatic uniqueness theorems.

  19. Characterization of coated conductors by magneto-optical imaging, Raman spectroscopy, and electron microscopy

    International Nuclear Information System (INIS)

    Argonne National Laboratory has established and implemented a coordinated set of characterization methods for coated-conductor specimens that can be applied in a manner compatible with further processing or utilization of the respective specimen. These characterization methods include measurements of superconductor transport properties, phase composition, microstructure, and epitaxy quality for YBCO-coated conductors that range in size up to multi-meters. Recent progress will be reported on the integrated application of Raman microscopy, magneto-optical imaging, and focused-ion-beam-assisted electron microscopy to a meter-length tape produced by SuperPower, Inc. This non-destructive, multifaceted characterization approach has allowed us to develop a seamless methodology for the interrogation of coated-conductor tapes during the course of sequential high-temperature treatments. The aim of this research effort is to identify performance-limiting defects, clarify their origin/cause, and prescribe methods to eliminate them during coated conductor manufacturing

  20. Skin effect mitigation in laser processed multi-walled carbon nanotube/copper conductors

    International Nuclear Information System (INIS)

    In this study, laser-processed multi-walled carbon nanotube (MWCNT)/Cu conductors are introduced as potential passive components to mitigate the skin effect of Cu at high frequencies (0–10 MHz). Suppressed skin effect is observed in the MWCNT/Cu conductors compared to primitive Cu. At an AC frequency of 10 MHz, a maximum AC resistance reduction of 94% was observed in a MWCNT/Cu conductor after being irradiated at a laser power density of 189 W/cm2. The reduced skin effect in the MWCNT/Cu conductors is ascribed to the presence of MWCNT channels which are insensitive to AC frequencies. The laser irradiation process is observed to play a crucial role in reducing contact resistance at the MWCNT-Cu interfaces, removing impurities in MWCNTs, and densifying MWCNT films

  1. Skin effect mitigation in laser processed multi-walled carbon nanotube/copper conductors

    Energy Technology Data Exchange (ETDEWEB)

    Keramatnejad, K.; Zhou, Y. S.; Gao, Y.; Rabiee Golgir, H.; Wang, M.; Lu, Y. F., E-mail: ylu2@unl.edu [Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0511 (United States); Jiang, L. [School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081 (China); Silvain, J.-F. [Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB-CNRS) 87, Avenue du Docteur Albert Schweitzer F-33608 Pessac Cedex (France)

    2015-10-21

    In this study, laser-processed multi-walled carbon nanotube (MWCNT)/Cu conductors are introduced as potential passive components to mitigate the skin effect of Cu at high frequencies (0–10 MHz). Suppressed skin effect is observed in the MWCNT/Cu conductors compared to primitive Cu. At an AC frequency of 10 MHz, a maximum AC resistance reduction of 94% was observed in a MWCNT/Cu conductor after being irradiated at a laser power density of 189 W/cm{sup 2}. The reduced skin effect in the MWCNT/Cu conductors is ascribed to the presence of MWCNT channels which are insensitive to AC frequencies. The laser irradiation process is observed to play a crucial role in reducing contact resistance at the MWCNT-Cu interfaces, removing impurities in MWCNTs, and densifying MWCNT films.

  2. Metallographic autopsies of full-scale ITER prototype cable-in-conduit conductors after full cyclic testing in SULTAN: III. The importance of strand surface roughness in long twist pitch conductors

    Science.gov (United States)

    Sanabria, Charlie; Lee, Peter J.; Starch, William; Devred, Arnaud; Larbalestier, David C.

    2016-07-01

    As part of the ITER conductor qualification process, 3 m long cable-in-conduit conductors (CICCs) were tested at the SULTAN facility under conditions simulating ITER operation so as to establish the current-sharing temperature, T cs, as a function of multiple full Lorentz force loading cycles. After a comprehensive evaluation of both the toroidal field (TF) and the central solenoid (CS) conductors, it was found that T cs degradation was common in long twist pitch TF conductors while short twist pitch CS conductors showed some T cs increase. However, one kind of TF conductors containing superconducting strand fabricated by the Bochvar Institute of Inorganic Materials (VNIINM) avoided T cs degradation despite having long twist pitch. In our earlier metallographic autopsies of long and short twist pitch CS conductors, we observed a substantially greater transverse strand movement under Lorentz force loading for long twist pitch conductors, while short twist pitch conductors had negligible transverse movement. With help from the literature, we concluded that the transverse movement was not the source of T cs degradation but rather an increase of the compressive strain in the Nb3Sn filaments possibly induced by longitudinal movement of the wires. Like all TF conductors this TF VNIINM conductor showed large transverse motions under Lorentz force loading, but T cs actually increased, as in all short twist pitch CS conductors. We here propose that the high surface roughness of the VNIINM strand may be responsible for the suppression of the compressive strain enhancement (characteristic of long twist pitch conductors). It appears that increasing strand surface roughness could improve the performance of long twist pitch CICCs.

  3. Reliability studies on printed conductors on flexible substrates under cyclic bending

    OpenAIRE

    Happonen, T. (Tuomas)

    2016-01-01

    Abstract This thesis investigates the reliability of printed conductors on flexible substrates under cyclic bending. The topic is approached by studying the effects of several key design parameters on the bending lifetime of printed conductors under dynamic loading. In this thesis, the test specimens with various cross-sectional geometries were printed on different plastic and paper substrates. The test samples were fabricated with two printing methods, silk screen and roll-to-roll pri...

  4. Creep testing of overhead line conductors; Essais de fluage des conducteurs de lignes aeriennes

    Energy Technology Data Exchange (ETDEWEB)

    Salomon, E.

    1997-12-31

    Two creep test rigs have been installed in a thermally-stable chamber, one operating at a temperature of 20 C, the second between 20 and 100 C. Under weight loading, deformations are measured over a conductor length of 100 times its diameter. Conductors made of aluminium-steel and homogenous aluminium alloy have been tested during a series of 6 times 1000 hours. Exponential creep relationships are derived from the results

  5. A Study of Students Attitudes towards the Choral Conductors Rehearsal Behaviours in Four Universities in Malaysia

    OpenAIRE

    Wong Kwan Yie

    2014-01-01

    This study was to survey university choral students regarding their views towards the choral conductor’s rehearsal behaviours utilized in the rehearsal setting by ranking the behaviours in the order of importance to them and to investigate the attitudes of university choral students towards their choral rehearsal. The author also surveyed conductors about the value they place upon conductor’s rehearsal behaviours in the choral rehearsal. A sample of 111 choral students and four conductors fro...

  6. Assessment of the noise annoyance among subway train conductors in Tehran, Iran

    OpenAIRE

    Mansoureh Hamidi; Amir Kavousi; Somayeh Zaheri; Abolfazl Hamadani; Roksana Mirkazemi

    2014-01-01

    Subway transportation system is a new phenomenon in Iran. Noise annoyance interferes with the individual′s task performance, and the required alertness in the driving of subway trains. This is the first study conducted to measure the level of noise and noise annoyance among conductors of subway organization in Tehran, Iran. This cross sectional study was conducted among 167 randomly selected train conductors. Information related to noise annoyance was collected by using a self-administered qu...

  7. Self-consistent modelling of nonlinear dynamic ESM microscopy in mixed ionic-electronic conductors

    OpenAIRE

    Varenyk, O. V.; Silibin, M. V.; D.A. Kiselev; Eliseev, E. A.; Kalinin, S. V.; Morozovska, A. N.

    2014-01-01

    Dynamic Electrochemical Strain Microscopy (ESM) response of mixed ionic-electronic conductors is analysed in the framework of the Thomas-Fermi screening theory and Vegard law with accounting of the steric effects. The emergence of dynamic charge waves and nonlinear deformation of the surface as result of applying probing voltage is numerically explored. 2D maps of the strain and concentration distribution across the mixed ionic-electronic conductor and bias-induced surface displacements for E...

  8. Simplified Calculation of Maximum Tensions of Split Conductors at Short Circuit

    OpenAIRE

    I. I. Sergey; A. P. Andrukevich

    2008-01-01

    A modified method for simplified calculation of the first maximum tension occurring in the conductors of split phase at short circuit has been developed in the paper. The paper contains evaluation of simplified calculation reliability while using calculative experiment in accordance with FAZA computer program and experimental data of foreign researchers. Graphs for determination of conductor bending angle while calculating maximum tension have been obtained in the paper and they permit signif...

  9. Simplified Calculation of Maximum Tensions of Split Conductors at Short Circuit

    Directory of Open Access Journals (Sweden)

    I. I. Sergey

    2008-01-01

    Full Text Available A modified method for simplified calculation of the first maximum tension occurring in the conductors of split phase at short circuit has been developed in the paper. The paper contains evaluation of simplified calculation reliability while using calculative experiment in accordance with FAZA computer program and experimental data of foreign researchers. Graphs for determination of conductor bending angle while calculating maximum tension have been obtained in the paper and they permit significantly to accelerate the process of calculation.

  10. Development of long YBCO coated conductors by multiple-stage CVD

    International Nuclear Information System (INIS)

    We have developed YBCO coated conductors by Multiple-Stage Chemical Vapor Deposition (MS-CVD) technique, which can make YBCO layer with high deposition rate and easy to scale up by increasing the number of reactors. We confirmed that the high speed production by the twelve-stage CVD equipment, which was designed to scale up CVD process, did not affect the property of YBCO coated conductors and that the YBCO coated conductors with I c of 100 A-class could be fabricated by the high speed production of 10 m/h. In order to demonstrate the advantage of the MS-CVD technique for longer YBCO coated conductors, we have also fabricated the 92-m-long YBCO conductor on an IBAD substrate. The YBCO conductor was fabricated with a tape moving at the speed of 25 m/h and was deposited several times to control the thickness of the YBCO films. The end-to-end I c of the 92-m-long YBCO tape was measured by criterion of 1 μV/cm and was 96 A (J c of 1.9 MA/cm2). We have successfully realized the fabrication of the YBCO coated conductor with the practical properties of 100 A-class in I c and 100 m-class in length. Recently, we have also obtained high I c of 227 A (J c of 2.3 MA/cm2) in a short sample of a YBCO conductor on IBAD substrates by optimization of the fabrication process

  11. New Development in the Preparation of Micro/Nano-Wires of Molecular (Magnetic) Conductors

    OpenAIRE

    Lydie Valade; Hisashi Tanaka; Dominique de Caro; Toyonari Sugimoto

    2010-01-01

    A lot of molecular (magnetic) conductors are prepared largely using charge-transfer (CT) salts of donor molecules with acceptor molecules or nonmagnetic or magnetic anions such as metal halides and oxides; their CT salts are usually obtained as bulk crystals, which are used to elucidate the electrical conducting (magnetic) properties. In contrast, a small number of micro/nano-crystals of the molecular (magnetic) conductors, especially micro/nano-wires, are known, of which highly conducting na...

  12. Analysis of Cable-in-Conduit Conductors' DC Performance in Light of Strand's Experimental Properties

    Institute of Scientific and Technical Information of China (English)

    TAN Yunfei; WENG Peide; LIU Fang; LI Shaolei

    2007-01-01

    Conductor qualification will be carried out with four Cable-in-Conduit Conductor (CICC) samples made of superconducting strands. The direct current (DC) performance of these samples will be tested in the SULTAN facility. The critical current densities of the strands can be well simulated by empirical equations. In this paper, a model is illustrated to predict the DC behaviour of the cable in light of the single strand's experimental properties. The simulation results were compared with experimental results.

  13. Aerodynamic and structural modeling for vortex-excited vibrations in bundled conductors

    OpenAIRE

    Verma, Himanshu

    2009-01-01

    Wind excited vibrations generated by the vortex shedding are very common in high-voltage overhead transmission lines. Although such vibrations are barely perceptible due to their low amplitudes (less than a conductor diameter), controlling them, however, is extremely important since they may lead to conductor fatigue. Mathematical models are therefore necessary for the computation of these vibrations, not only to evaluate the risk of potential damage to the transmission line but also for stud...

  14. Fluid dynamics of supercritical helium within cable-in-conduit conductors

    Science.gov (United States)

    Vansciver, S. W.

    1992-07-01

    The enclosed report summarizes work carried out under DOE/MFE support during the past four years. Emphasis is placed on progress within the last year. Results of experiments on pressure drop and heat transfer within several cable-in-conduit conductors are described. These results are compared to models for flow in similar geometrics. The work provides a basis for design of magnets using the CIC conductor concept.

  15. A comparative analysis of graphene oxide films as proton conductors

    Science.gov (United States)

    Smirnov, V. A.; Denisov, N. N.; Dremova, N. N.; Vol'fkovich, Y. M.; Rychagov, A. Y.; Sosenkin, V. E.; Belay, K. G.; Gutsev, G. L.; Shulga, N. Yu.; Shulga, Y. M.

    2014-12-01

    The electrical conductivity of graphene oxide (GO) films in vapors of water and acid solutions is found to be close to the conductivity of a film formed after drying the solution of phenol-2,4-disulfonic acid in polyvinyl alcohol, which is known to be a proton conductor. We found that the conductivity of a GO film in vapors of the H2O-H2SO4 electrolyte possesses a sharp maximum at ~1 % by weight of sulfuric acid. The highest conductivity of GO films can be expected when placing the films over acid vapors where the acid concentration is essentially lower than in the acid solutions at their maximum conductivity. Since the conductivity of the H2O-H2SO4 electrolyte itself has a maximum at ~30 % by weight of sulfuric acid, the use of intermediate concentrations of H2SO4 is recommended in practical applications. The GO films permeated with water or acid solution in water are expected to possess the proton-exchange properties similar to those of other proton-exchanging membranes.

  16. Volume conductor model of transcutaneous electrical stimulation with kilohertz signals

    Science.gov (United States)

    Medina, Leonel E.; Grill, Warren M.

    2014-12-01

    Objective. Incorporating high-frequency components in transcutaneous electrical stimulation (TES) waveforms may make it possible to stimulate deeper nerve fibers since the impedance of tissue declines with increasing frequency. However, the mechanisms of high-frequency TES remain largely unexplored. We investigated the properties of TES with frequencies beyond those typically used in neural stimulation. Approach. We implemented a multilayer volume conductor model including dispersion and capacitive effects, coupled to a cable model of a nerve fiber. We simulated voltage- and current-controlled transcutaneous stimulation, and quantified the effects of frequency on the distribution of potentials and fiber excitation. We also quantified the effects of a novel transdermal amplitude modulated signal (TAMS) consisting of a non-zero offset sinusoidal carrier modulated by a square-pulse train. Main results. The model revealed that high-frequency signals generated larger potentials at depth than did low frequencies, but this did not translate into lower stimulation thresholds. Both TAMS and conventional rectangular pulses activated more superficial fibers in addition to the deeper, target fibers, and at no frequency did we observe an inversion of the strength-distance relationship. Current regulated stimulation was more strongly influenced by fiber depth, whereas voltage regulated stimulation was more strongly influenced by skin thickness. Finally, our model reproduced the threshold-frequency relationship of experimentally measured motor thresholds. Significance. The model may be used for prediction of motor thresholds in TES, and contributes to the understanding of high-frequency TES.

  17. Eddy damping effect of additional conductors in superconducting levitation systems

    Science.gov (United States)

    Jiang, Zhao-Fei; Gou, Xiao-Fan

    2015-12-01

    Passive superconducting levitation systems consisting of a high temperature superconductor (HTSC) and a permanent magnet (PM) have demonstrated several fascinating applications such as the maglev system, flywheel energy storage. Generally, for the HTSC-PM levitation system, the HTSC with higher critical current density Jc can obtain larger magnetic force to make the PM levitate over the HTSC (or suspended below the HTSC), however, the process of the vibration of the levitated PM, provides very limited inherent damping (essentially hysteresis). To improve the dynamic stability of the levitated PM, eddy damping of additional conductors can be considered as the most simple and effective approach. In this article, for the HTSC-PM levitation system with an additional copper damper attached to the HTSC, we numerically and comprehensively investigated the damping coefficient c, damping ratio, Joule heating of the copper damper, and the vibration frequency of the PM as well. Furthermore, we comparatively studied four different arrangements of the copper damper, on the comprehensive analyzed the damping effect, efficiency (defined by c/VCu, in which VCu is the volume of the damper) and Joule heating, and finally presented the most advisable arrangement.

  18. Organic conductor/high-Tc superconductor bilayer structures

    International Nuclear Information System (INIS)

    Electrochemical techniques are exploited to fabricate conducive polymer/high-Tc superconductor bilayer structures. Scanning electron microscopy and electrochemical techniques are utilized to characterize the electrodeposition of polypyrrole layers grown onto YBa2Cu3O7-δ films. In such hybrid polymer/superconductor systems, it is found that when the polymer is oxidized to its conductive state, the transition temperature (Tc) and critical currents (Jc) of the underlying superconductor films are suppressed. Reversible modulation of the values of the transition temperatures of up to 50 K are noted for these structures. Upon reduction of the conductive polymer layer back to its non-conductive form, both Tc and Jc are found to return to values close to those acquired for the underivatized YBa2Cu3O7-δ films. Moreover, measurements as a function of temperature of the polymer/superconductor interface resistance show dramatic decrease in this value at Tc. Also, estimates of superconducting coherence lengths within the organic conductor samples suggest superconducting properties over macroscopically large distances within the organic materials can be expected. Collectively these results are consistent with the first observation of a conductive polymer proximity effect

  19. Biaxially textured copper-iron alloys for coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Gallistl, Bernhard; Hassel, Achim Walter [Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University, Altenberger Str. 69, 4040 Linz (Austria); Kirchschlager, Raimund [Institute for Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Str. 69, 4040 Linz (Austria)

    2012-05-15

    Two copper based biaxially textured alloys containing 0.37 and 0.91 wt.%-Fe have been investigated for the use as substrate material for coated conductors. Average full width at half maximum (FWHM) values of 7.3 (CuFe0.37) and 6.8 (CuFe0.91) for in-plane alignment and 7.2 (CuFe0.37, CuFe0.91) for out-of-plane are achieved. Ultimate tensile strength for the two alloys is found to be much higher compared to the values for Cu and CuFe2.35. Hysteresis losses are dramatically reduced compared to other available substrate materials. Magnetisation data for both alloys obtained at 5 K show an anticipated saturation magnetisation (M{sub s}) <0.35 {mu}Wb m kg{sup -1}, which is less than 1% of pure Ni. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. The ATLAS SemiConductor tracker-overview and status

    CERN Document Server

    Eklund, L

    2002-01-01

    The ATLAS SemiConductor Tracker (SCT) in one of the three tracking detectors making up the ATLAS inner detector. The trackers 4088 r modules covers an area of over 60 m/sup 2/, distributed over four barrel cylinders and 18 end-cap disks. The back-to-back mounted silicon sensors provide space points for track reconstruction. The sensors are read out via front-end ASIC and binary data from selected events are read out via optical links. A large number of prototypes have been built and measured with test pulses, in beam tests and in a small-scale system tests. The radiation hardness of the components has been verified by a series of irradiations with subsequent thorough measurement programs. The SCT is now close to its final design and series production of detector modules is about to start. The final assembly and quality assurance of the SCT detector modules will be done in production at universities, organizing themselves in production clusters. (7 refs).

  1. Aluminum alloy production for the reinforcement of the CMS conductor

    CERN Document Server

    Sequeira-Lopes-Tavares, S; Campi, D; Curé, B; Horváth, I L; Riboni, P; Sgobba, Stefano; Smith, R P

    2002-01-01

    The Compact Muon Solenoid (CMS) is one of the general-purpose detectors to be provided for the Large Hadron Collider (LHC) project at CERN. The design field of the CMS superconducting magnet is 4 T, the magnetic length is 12.5 m and the free bore is 6 m. To reinforce the high-purity (99.998%) Al-stabilized conductor of the magnet against the magnetic loadings experienced during operation at 4.2 K, two continuous sections of Al-alloy (AA) reinforcement are Electron Beam (EB) welded to it. The reinforcements have a section of 24*18 mm and are produced in continuous 2.55 km lengths. The alloy EN AW-6082 has been selected for the reinforcement due to its excellent extrudability, high strength in the precipitation hardened states, high toughness and strength at cryogenic temperature and good EB weldability. Each of the continuous lengths of the reinforcement is extruded billet on billet and press quenched on-line from the extrusion temperature in an industrial extrusion plant. In order to insure the ready EB welda...

  2. Magneto-optical studies of low-dimensional organic conductors

    Directory of Open Access Journals (Sweden)

    Hitoshi Ohta, Motoi Kimata and Yugo Oshima

    2009-01-01

    Full Text Available Our periodic orbit resonance (POR results on quasi-two-dimensional (q2D, highly anisotropic q2D and quasi-one-dimensional (q1D organic conductors are reviewed together with our rotational cavity magneto-optical measurement system. Higher order POR up to seventh order has been observed in the q2D system (BEDT-TTF2Br(DIA, and the experimental conditions to observe POR and the cyclotron resonance (CR are discussed. Highly anisotropic q2D Fermi surface (FS in β''-(BEDT-TTF(TCNQ, which was considered to have q1D FS previously, is proposed by our POR measurements, and the possible interpretations of other experimental results of β''-(BEDT-TTF(TCNQ are discussed assuming the highly anisotropic q2D FS. Finally, detailed q1D FS of (DMET2I3, obtained from our POR results, is discussed in connection with the typical q1D system (TMTSF2ClO4.

  3. Coupling losses of fusion conductors: Influence of some design parameters

    International Nuclear Information System (INIS)

    Superconductors for fusion are subjected to fast variations of magnetic fields. The effective diameter of the strands is of great importance to limit the level of losses appearing during theses variations. Another less controlled characteristic also plays a major role: the conductor time constant. A model is given to calculate this time constant. The void fraction, the twist pitches associated to the different stages, the chromium coating and the internal resistive barriers inside the strand influence greatly this time constant. The influence of the different parameters is discussed through practical considerations depending on the kind of cable considered. This model is applied to measurements performed at the University of Twente and at CEA on Nb3Sn subcables made of twisted strands relevant for ITER. The application of this model is also discussed for a typical NbTi strand for fusion application developed by GEC AISA. As a matter of fact, the NbTi is again present in the ITER design for most of the poloidal field coils, which represents hundreds tons of material

  4. Conduction Mechanisms and Structure of Ionomeric Single-Ion Conductors

    Energy Technology Data Exchange (ETDEWEB)

    Colby, Ralph H.; Maranas, Janna K; Mueller, Karl T; Runt, James; Winey, Karen I

    2015-03-05

    Our team has designed using DFT (Gaussian) and synthesized low glass transition temperature single-ion conductors that are either polyanions that conduct small cations Li, Na, Cs or polycations that conduct small anions F, OH, Br. We utilize a wide range of complimentary experimental materials charactization tools to understand ion transport; differential scanning calorimetry, dielectric relaxation spectroscopy, infrared spectroscopy, nuclear magnetic resonance spectroscopy, linear viscoelasticity, X-ray scattering and molecular dynamics simulations. The glass transition temperature Tg needs to be as low as possible to facilitate ion transport, so the nonionic parts of the polymer need to be polar, flexible and have strong solvation interactions with the ions. The lowest Tg we have managed for polyanions conducting Li is -60 C. In contrast, polysiloxanes with PEO side chains and tetrabutylphosphonium cationic side groups have Tg ~ -75C that barely increases with ion content, as anticipated by DFT. A survey of all polyanions in the literature suggests that Tg < -80C is needed to achieve the 10-4 S/cm conductivity needed for battery separators.

  5. Na+ and Li+ NASICON Superionic Conductors Thick Films

    Science.gov (United States)

    Perthuis, H.; Velasco, G.; Colomban, Ph.

    1984-05-01

    For microionic applications, superionic conductors have been elaborated in the form of thick films, using silk-screen printable powders. Na3Zr2Si2PO12, Na3.1Zr1.55Si2.3P0.7O11 and Li0.8Zr1.8Ta0.2(PO4)3 compositions are synthesized by a sol-gel process involving hydrolysis-polycondensation reactions of metal-organic alcoholic solutions. A thermal treatment (600°C-800°C) allows to obtain very fine particles (Inks are prepared with these powders, an organic binder, volatile fluidifying agents and mineralizers. The layers, about 50 μm in thickness, are achieved by successive deposits and sinterings (950°C-1050°C) onto alumina substrates. Films conductivity is determined by the complex impedance method. Values measured at 300°C (Na+: σ˜10-2 Ω-1cm-1, EA{=}0.25 eV, Li+: σ˜5 10-4 Ω-1cm-1, EA{=}0.5 eV) reach those obtained with well-densified ceramics. An anisotropic behaviour related to microstructure is pointed out.

  6. Study of superionic conductors dynamics by continued diffusion model

    International Nuclear Information System (INIS)

    The superionic conductors form a special category of solids characterized by their remarkable transport properties and are in general, Simplified as being constituted by the superposition of two inter penetrable crystal lattices. The ions of the first one form a rigid structure through which the other ions of opposite charge diffuse in quasi-liquid way. Basing on experimental and theoretical arguments, it was proved necessary to adopt a model of N-body continued diffusion which the basic theory is that of brownian movement. This thesis deals with the study of the dynamic structure factor S (q,w) and its line half width by the method of development in continued fractions issued from the Mori theory. With regard to the analytical difficulty met at the time of the static correlations functions calculation, the homogeneous approximation was applied and the notion of effective strength was introduced. So, it was obtained general relationships which give the static correlation functions, only in term of the static structure factor of liquids and effective potential. 98 refs.; 22 figs. (F.M.)

  7. The superconducting strand for the CMS solenoid conductor

    CERN Document Server

    Curé, B; Campi, D; Goodrich, L F; Horváth, I L; Kircher, F; Liikamaa, R; Seppälä, J; Smith, R P; Teuho, J; Vieillard, L

    2002-01-01

    The Compact Muon Solenoid (CMS) is one of the general-purpose detectors to be provided for the LHC project at CERN. The design field of the CMS superconducting magnet is 4 T, the magnetic length is 12.5 m and the free bore is 6 m. Approximately 2000 km of superconducting strand is under procurement for the conductor of the CMS superconducting solenoid. Each strand length is required to be an integral multiple of 2.75 km. The strand is composed of copper- stabilized multifilamentary Nb-Ti with Nb barrier. Individual strands are identified by distinctive patterns of Nb-Ti filaments selected during stacking of the monofilaments. The statistics of piece length, measurements of I/sub c/, n-value, copper RRR, (Cu+Nb)/Nb-Ti ratio, as well as the results of independent cross checks of these quantities, are presented. A study was performed on the CMS strands to investigate the critical current degradation due to various heat treatments. The degradation versus annealing temperature and duration are reported. (4 refs).

  8. Development of coated conductors by inclined substrate deposition

    Science.gov (United States)

    Balachandran, U.; Ma, B.; Li, M.; Fisher, B. L.; Koritala, R. E.; Miller, D. J.; Dorris, S. E.

    2003-10-01

    Inclined substrate deposition (ISD) offers the potential for rapid production of high-quality biaxially textured buffer layers suitable for YBa 2Cu 3O 7- δ (YBCO)-coated conductors. We have grown biaxially textured magnesium oxide (MgO) films on Hastelloy C276 (HC) substrates by ISD at deposition rates of 20-100 Å/s. Scanning electron microscopy of the ISD MgO films showed columnar grain structures with a roof-tile-shaped surface. X-ray pole figure analysis revealed that the c-axis of the ISD MgO films is titled at an angle ≈32° from the substrate normal. A small full-width at half maximum of ≈9° was observed for the φ-scan of MgO films. YBCO films were grown on ISD MgO buffered HC substrates by pulsed laser deposition and were determined to be biaxially aligned with the c-axis parallel to the substrate normal. The orientation relationship between the ISD template and the top YBCO film was investigated by X-ray pole figure analysis and transmission electron microscopy. A transport critical current density of Jc=5.5×10 5 A/cm 2 at 77 K in self-field was measured on a YBCO film that was 0.46-μm thick, 4-mm wide, 10-mm long.

  9. Development of coated conductors by inclined substrate deposition

    International Nuclear Information System (INIS)

    Inclined substrate deposition (ISD) offers the potential for rapid production of high-quality biaxially textured buffer layers suitable for YBa2Cu3O7-δ (YBCO)-coated conductors. We have grown biaxially textured magnesium oxide (MgO) films on Hastelloy C276 (HC) substrates by ISD at deposition rates of 20-100 Angst. Scanning electron microscopy of the ISD MgO films showed columnar grain structures with a roof-tile-shaped surface. X-ray pole figure analysis revealed that the c-axis of the ISD MgO films is titled at an angle ∼32 deg. from the substrate normal. A small full-width at half maximum of ∼9 deg. was observed for the phi-scan of MgO films. YBCO films were grown on ISD MgO buffered HC substrates by pulsed laser deposition and were determined to be biaxially aligned with the c-axis parallel to the substrate normal. The orientation relationship between the ISD template and the top YBCO film was investigated by X-ray pole figure analysis and transmission electron microscopy. A transport critical current density of Jc=5.5x105 A/cm2 at 77 K in self-field was measured on a YBCO film that was 0.46-μm thick, 4-mm wide, 10-mm long

  10. Development of coated conductors by inclined substrate deposition

    Energy Technology Data Exchange (ETDEWEB)

    Balachandran, U.; Ma, B.; Li, M.; Fisher, B.L.; Koritala, R.E.; Miller, D.J.; Dorris, S.E

    2003-10-15

    Inclined substrate deposition (ISD) offers the potential for rapid production of high-quality biaxially textured buffer layers suitable for YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO)-coated conductors. We have grown biaxially textured magnesium oxide (MgO) films on Hastelloy C276 (HC) substrates by ISD at deposition rates of 20-100 Angst. Scanning electron microscopy of the ISD MgO films showed columnar grain structures with a roof-tile-shaped surface. X-ray pole figure analysis revealed that the c-axis of the ISD MgO films is titled at an angle {approx}32 deg. from the substrate normal. A small full-width at half maximum of {approx}9 deg. was observed for the phi-scan of MgO films. YBCO films were grown on ISD MgO buffered HC substrates by pulsed laser deposition and were determined to be biaxially aligned with the c-axis parallel to the substrate normal. The orientation relationship between the ISD template and the top YBCO film was investigated by X-ray pole figure analysis and transmission electron microscopy. A transport critical current density of J{sub c}=5.5x10{sup 5} A/cm{sup 2} at 77 K in self-field was measured on a YBCO film that was 0.46-{mu}m thick, 4-mm wide, 10-mm long.

  11. Large Scale Assembly and Characterization of BI-2223 HTS Conductors

    CERN Document Server

    Ballarino, Amalia; Mathot, Serge; Taylor, T; Brambilla, R

    2007-01-01

    The powering of the LHC machine requires more than 1000 High Temperature Superconducting (HTS) current leads. These leads contain, at their cold end, HTS conductors made of stacks of Bi-2223 tape with gold-doped silver matrix. CERN specified and purchased 31 km of this material, which was delivered on spools in unit lengths of 100 to 300 m. On reception the tape was inspected, cut into short length and vacuum soldered into stacks. All stacks were characterized in liquid nitrogen using a measuring procedure and set-up specifically developed for this purpose. Contact resistance values and critical currents at different electric field criteria were measured, from which the n-values have been extrapolated from the experimental V-I characteristics. This paper reports on the assembly and electrical characterization (up to 800 A) of more than ten thousand Bi-2223 stacks. Three types of stack were made from tape from two manufacturers. The assembly and soldering procedures and the set-up for the series electrical cha...

  12. An A15 conductor design and its implications for the NET-II TF coils

    International Nuclear Information System (INIS)

    The paper describes the results of studies for a NET toroidal field coil conductor carried out at KfK-Karlsruhe. The conductor concept is based on the same design principles as used in the Euratom-LCT coil, well proven in all conductor tests and the domestic tests of the coil. These principles are applied to the peculiarities of Nb3Sn for a rated current of 20 kA at 12 T, taking into account ac losses and nuclear heating. A flat Nb3Sn cable is soldered to a surrounding CuNi tape after reaction. Around this rectangular conductor core, Cu profiles are cabled on distance by the Roebel-process and subsequently soldered onto the CuNi tape. The whole system is surrounded by a steel conduit. The conductor data result from electric, thermohydraulic and stability calculations as well as mechanical evaluations. Expected fabrication processes are discussed, and measurements on a first simplified subsize conductor model are presented. (orig.)

  13. Recent developments in fabrication and properties of Ag-clad BSCCO conductors

    International Nuclear Information System (INIS)

    Long-length mono- and multifilament Ag-clad BSCCO (Bi-Sr-Ca-Cu-O) superconductors with consistent current transport properties were fabricated by the powder-in-tube method. Ic of 42 A was recorded in short lengths of 37 filament conductors. Jc up to 12,000 A/cm2 was observed at 77 K in 124-m-long monocore andd 850-m-long multifilament conductors. A high-Tc magnet, fabricated from 770 m of monofilament conductor, generated a high field of ∼1 T at 4.2 K in a field of ∼20 T. In-situ strain tests showed that multifilament conductors have better strain tolerance than monofilament conductors. In-situ bending of the monofilament conductors indicate that their irreversible strain limit increases with decreasing superconductor/Ag ratio. Superconducting joints and multilayer Ag/superconductor composites have been fabricated by chemical etching. Typical Ic through such joints was 23 A, or ∼70% of that carried by normal monofilament tapes and ∼60% of that carried by multifilament tapes. Preliminary results with multilayer tapes show that continuous Ag reinforcement of the BSCCO core improves strain tolerance of the tapes so they can carry 90% of their initial I2 at 1% bend strain ins pite of a higher superconductor/Ag ratio than unreinforced tapes

  14. Manufacturing and test of 2G-HTS coils for rotating machines: Challenges, conductor requirements, realization

    International Nuclear Information System (INIS)

    We investigate the use of 2nd-generation High-Temperature Superconductors (2G-HTSs) in the rotors of electrical motors and generators. For these devices the conductor must be wound into robust impregnated coils, which are operated in vacuum at temperatures around 30 K, in strong magnetic fields of about 2T. Differences in thermal contraction between the coil former, conductor constituents, impregnation resin, bandage and heat-sink materials (assembled at room temperature) cause mechanical stresses at operating temperature. Rotating-machine operation adds Lorentz forces and challenging centripetal accelerations up to thousands of g. Second generation-HTS conductors withstand large tensile stresses in axial direction and compression in normal direction. However, shear stresses, axial compression, and tension normal to the conductor can cause degradation in superconducting properties. Such stresses can be mitigated by correct choice of materials, coil lay-out and manufacturing process. A certain stress level will remain, which the conductor must withstand. We have manufactured many impregnated round and race-track coils, using different 2G-HTS conductors, and tested them at temperatures from 25 K to 77 K. Degradation of the superconductor in early coils was traced to the mentioned differences in thermal contraction, and was completely avoided in coils produced later. We will discuss appropriate coil-winding techniques to assure robust and reliable superconductor performance.

  15. The effect of volume conductor modeling on the estimation of cardiac vectors in fetal magnetocardiography

    International Nuclear Information System (INIS)

    Previous studies based on fetal magnetocardiographic (fMCG) recordings used simplified volume conductor models to estimate the fetal cardiac vector as an unequivocal measure of the cardiac source strength. However, the effect of simplified volume conductor modeling on the accuracy of the fMCG inverse solution remains largely unknown. Aiming to determine the sensitivity of the source estimators to the details of the volume conductor model, we performed simulations using fetal–maternal anatomical information from ultrasound images obtained in 20 pregnant women in various stages of pregnancy. The magnetic field produced by a cardiac source model was computed using the boundary-element method for a piecewise homogeneous volume conductor with three nested compartments (fetal body, amniotic fluid and maternal abdomen) of different electrical conductivities. For late gestation, we also considered the case of a fourth highly insulating layer of vernix caseosa covering the fetus. The errors introduced for simplified volume conductors were assessed by comparing the reconstruction results obtained with realistic versus spherically symmetric models. Our study demonstrates the significant effect of simplified volume conductor modeling, resulting mainly in an underestimation of the cardiac vector magnitude and low goodness-of-fit. These findings are confirmed by the analysis of real fMCG data recorded in mid-gestation. (paper)

  16. Skin electric explosion in double-layer conductors with a low-conductivity deposited layer

    Science.gov (United States)

    Datsko, I. M.; Labetskaya, N. A.; Chaikovsky, S. A.; Shugurov, V. V.

    2016-06-01

    The experiments on explosion of cylindrical conductors aimed at comparison of plasma formation during skin explosion of homogeneous and double-layer conductors with an external layer with a lower conductivity are carried out on a high-current MIG generator (current amplitude up to 2.5 MA and current rise time 100 ns). The generator is loaded with cylindrical copper conductors with a diameter of 3 mm on the cathode part of which a titanium layer of thickness 20, 50, and 80 μm is deposited in vacuum. This type of loading makes it possible to compare the behaviors of the homogeneous and double-layer conductors in identical conditions. It is shown that using the double-layer structure of the conductor with an external layer of thickness 20-80 μm with a lower conductivity, which is obtained by vacuum arc deposition, higher values of magnetic induction (as compared to homogeneous conductor) can be attained on its surface prior to plasma formation and spread.

  17. Powder-in-tube (PIT) $Nb_{3}Sn$ conductors for high-field magnets

    CERN Document Server

    Lindenhovius, J L H; den Ouden, A; Wessel, W A J; ten Kate, H H J

    2000-01-01

    New Nb/sub 3/Sn conductors, based on the powder-in-tube (PIT) process, have been developed for application in accelerator magnets and high-field solenoids. For application in accelerator magnets, SMI has developed a binary 504 filament PIT conductor by optimizing the manufacturing process and adjustment of the conductor lay-out. It uniquely combines a non-copper current density of 2680 A/mm/sup 2/@10 T with an effective filament diameter of about 20 mu m. This binary conductor may be used in a 10 T, wide bore model separator dipole magnet for the LHC, which is being developed by a collaboration of the University of Twente and CERN. A ternary (Nb/7.5wt%Ta)/sub 3/Sn conductor containing 37 filaments is particularly suited for application in extremely high-field superconducting solenoids. This wire features a copper content of 43%, a non-copper current density of 217 A/mm/sup 2/@20 T and a B/sub c2/ of 25.6 T. The main issues and the experimental results of the development program of PIT Nb/sub 3/Sn conductors a...

  18. Chemically deposed layer sytems for the realization of YBa2Cu3O7-δ band conductors

    International Nuclear Information System (INIS)

    The aim of this thesis was to produce new buffer-layer systems for biaxially texturated Ni5at%W substrates by means of chemical processes. As very promising materials for the buffer layers CaTiO3 and SrTiO3 were chosen. The production of the single layers pursued from the organometallic prestage by means of dip coating and subsequent head treatment. During the work first the single precursor solutions were to be developed. A main component of the theses forms the understanding of the texture development during the heat treatment of precursor layers on biaxially texturated metallic substrates. Based on this the growth of thick buffer layers is studied and by means of YBCO layers, which were deposed by beans of a pulsed laser, the functionality of the synthesized buffer layers proved. A further component of this thesis formes the influence of nanoscaling precipitations in thew YBCO on its superconducting properties. The YBCO deposition pursued via a variation of the TFA process, as substrate (001)-oriented SrTiO3 monocrystals were applied

  19. Coherent THz wave induced excitation in superionic conductors

    Energy Technology Data Exchange (ETDEWEB)

    Awano, T [Tohoku Gakuin University, Tagajo, Miyagi 985-8537 (Japan); Takahashi, T, E-mail: awano@tjcc.tohoku-gakuin.ac.j [Kyoto University Research Reactor Institute, Kumatori, Osaka 590-0494 (Japan)

    2009-02-01

    Millimeter wave absorption spectra of silver halides doped silver phosphate glasses were measured using an intense coherent transition radiation. Two bands were observed at 8.4cm{sup -1} and 6.3cm{sup -1} in AgI doped AgPO{sub 3} glass and 8.7cm{sup -1} and 6.1cm{sup -1} in AgBr doped one. Small difference of peak positions between these glasses suggests that these absorption bands are concerned with a large number of silver ions in dopant molecules.

  20. Banded transformer cores

    Science.gov (United States)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  1. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  2. Amniotic Band Syndrome

    OpenAIRE

    Shetty, Prathvi; Menezes, Leo Theobald; Tauro, Leo Francis; Diddigi, Kumar Arun

    2012-01-01

    Amniotic band syndrome is an uncommon congenital disorder without any genetic or hereditary disposition. It involves fetal entrapment in strands of amniotic tissue and causes an array of deletions and deformations. Primary treatment is plastic and reconstructive surgery after birth with in utero fetal surgery also coming in vogue.

  3. Effect of wire arrangements on AC transport losses in cylindrical conductors composed of Ag-sheathed Bi2223 tapes

    International Nuclear Information System (INIS)

    The AC transport self-field losses at 77 K were investigated on the double-layer cylindrical conductors composed of Ag-sheathed Bi2223 tapes. The multifilamentary tapes as the strands are arranged in a parallel way on the cylindrical former with a diameter of 10.5 mm. The loss values are strongly influenced by the arrangements of tape strands in the conductors. The loss generation in conductors enhances with increasing of the separation between the layers and gap length between the adjacent tapes in the outer-layer. From the numerical calculations of the loss density distributions per-cycle in the conductors, it is suggested that the difference in loss values for each conductor is attributed to the magnetic flux distributions due to self-field and loss generations in tape strands, varying with the arrangement of tape strands in the conductors

  4. Effect of chrome plating on coupling losses in a Nb3Sn cable-in-conduit conductor

    International Nuclear Information System (INIS)

    Time constant of decay of coupling current was measured on cable-in-conduit conductors which consist of twelve Nb3Sn strands with chrome plating. The time constant measurement was performed by observing exponential decrease of induced coupling current in conductors. The measured time constant of conductor composed of bare strands was 4.5 times larger than that of the single strand, in case that a void fraction of conductor was 30%. However, the time constant of conductor composed of strands with chrome plating of more than 2 μm thickness was equal to that of the single strand. These results show that chrome plating on strands is effective for decrease of coupling losses in Nb3Sn cable-in-conduit conductors. (author)

  5. Gain-Enhanced On-Chip Antenna Utilizing Artificial Magnetic Conductor Reflecting Surface at 94 GHz

    KAUST Repository

    Nafe, Mahmoud

    2015-08-04

    Nowadays, there is a growing demand for high frequency-bandwidth mm-wave (30-300 GHz) electronic wireless transceiver systems to support applications such as high data-rate wireless communication and high resolution imaging. Such mm-wave systems are becoming more feasible due to the extreme transistor downscaling in silicon-based integrated circuits, which enabled densely-integrated high-speed elec- tronics operating up to more than 100 GHz with low fabrication cost. To further enhance system integrability, it is required to implement all wireless system compo- nents on the chip. Presently, the last major barrier to true System-on-Chip (SoC) realization is the antenna implementation on the silicon chip. Although at mm-wave frequencies the antenna size becomes small enough to fit on chip, the antenna performance is greatly deteriorated due the high conductivity and high relative permittivity of the silicon substrate. The negative e↵ects of the silicon substrate could be avoided by using a metallic reflecting surface on top of silicon, which e↵ectively isolates the antenna from the silicon. However, this approach has the shortcoming of having to implement the antenna on the usually very thin silicon oxide layer of a typical CMOS fabrication process (10’s of μm). This forces the antenna to be in a very close proximity (less than one hundredth of a wavelength) to the reflecting surface. In this regime, the use of conventional metallic reflecting surface for silicon shielding has severe e↵ects on the antenna performance as it tends to reduce the antenna radiation resistance resulting in most of the energy being absorbed rather than radiated. In this work, the use of specially patterned reflecting surfaces for improving on- chip antenna performance is investigated. By using a periodic metallic surface on top of a grounded substrate, the structure can mimic the behavior of a perfect mag- netic conductor, hence called Artificial Magnetic Conductor (AMC) surface

  6. Current distribution in Cable-In-Conduit Conductors

    International Nuclear Information System (INIS)

    A numerical study of the current distribution in Cable-In-Conduit Conductors (CICC's) experiencing linearly ramping transport currents and transverse magnetic fields was conducted for both infinitely long, periodic cables and finite length cables terminated in low resistance joints. The goal of the study was to gain insight into the phenomenon known as Ramp Rate Limitation, an as yet unexplained correspondence between maximum attainable current and the ramp time taken to reach that current in CICC superconducting magnets. A discrete geometric model of a 27 strand multiply twisted CICC was developed to effectively represent the flux linkages, mutual inductances, and resistive contact points between the strands of an experimentally tested cable. The results of the numerical study showed that for fully periodic cables, the current imbalances due to ramping magnetic fields and ramping transport currents are negligible in the range of experimentally explored operating conditions. For finite length, joint terminated cables, however, significant imbalances can exist. Unfortunately, quantitative results are limited by a lack of knowledge of the transverse resistance between strands in the joints. Nonetheless, general results are presented showing the dependency of the imbalance on cable length, ramp time, and joint resistance for both ramping transverse magnet fields and ramping transport currents. At the conclusion of the study, it is suggested that calculated current imbalances in a finite length cable could cause certain strands to prematurely ''quench'' -- become non-superconducting --thus leading to an instability for the entire cable. This numerically predicted ''current imbalance instability'' is compared to the experimentally observed Ramp Rate Limitation for the 27 strand CICC sample

  7. The ATLAS SemiConductor Tracker operation and performance

    Science.gov (United States)

    Pater, J. R.

    2012-04-01

    The ATLAS SemiConductor Tracker (SCT) is a key precision tracking detector in the ATLAS experiment at CERN's Large Hadron Collider. The SCT is composed of 4088 planar p-in-n silicon micro-strip detectors. The signals from the strips are processed in the front-end ABCD3TA ASICs, which operate in binary readout mode; data are transferred to the off-detector readout electronics via optical fibres. The SCT was completed in 2007. An extensive commissioning phase followed, during which calibration data were collected and analysed to determine the noise performance of the system, and further performance parameters of the detector were determined using cosmic ray data, both with and without magnetic field. After the commissioning phase, the SCT was ready for the first LHC proton-proton collisions in December 2009. From the beginning of data taking, the completed SCT has been in very good shape with more than 99% of its 6.3 million strips operational; the detector is well timed-in and the operational channels are 99.9% efficient in data acquisition. The noise occupancy and hit efficiency are better than the design specifications. The detector geometry is monitored continuously with a laser-based alignment system and is stable to the few-micron level; the alignment accuracy as determined by tracks is near specification and improving as statistics increase. The sensor behaviour in the 2T solenoidal magnetic field has been studied by measuring the Lorentz angle. Radiation damage in the silicon is monitored by periodic measurements of the leakage current; these measurements are in reasonable agreement with predictions.

  8. Progress on TFA-MOD coated conductor development

    International Nuclear Information System (INIS)

    The recent progress in coated conductor development by the TFA-MOD process was reviewed. Much progress was recognized in the R and D on TFA-MOD processing for satisfying several requirements, such as high superconducting performance, long tape production, high production rate, etc., considering the real application. For high superconducting performance, the high I c value of 413 A was achieved in a short sample with an architecture of MOD-YBCO/IBAD-GZO/IBAD-GZO/Hastelloy. It was realized by improving the in-plane crystal grain alignment of the CeO2 buffer layer and optimizing conditions of the heat treatments in the calcination and crystallization processes. In the calcination process, it was found that lower heating rate was effective to improve the morphology of the multi-layered precursor by preventing from pore generation and segregation of Cu elements. In the crystallization process, it was found that high humid gas partial pressure was effective to improve the J c values by reducing the amounts and size of pores in the YBCO layers. Furthermore, in the case of thicker firm, it was found that the low heating rate in the crystallization process was effective to prevent from the crack formation. On the other hand, in order to obtain the long tape with uniform I c values, in the crystallization process, the gas flow condition in a large scale equipment for the continuous long tape process was investigated using a computer simulation technique. Consequently, the 8.6 m YBCO on PLD-CeO2/IBAD-Gd2Zr2O7/Hastelloy tape which shows high I c performance of 119 A as an end-to-end value at 77.3 K in self fields, was successfully obtained. As a result, I c x L(length) value of 1024 A m was achieved

  9. Crossover exponents in percolating superconductor endash nonlinear-conductor mixtures

    International Nuclear Information System (INIS)

    The nonlinear response is studied in a two-component composite with concentration p of superconductor (S) and concentration 1-p of normal conductor (N) with nonlinear response of the form J=σ1E+χ1Eβ (β approx-gt 1). Below the percolation threshold pc of the superconductor, the response of the composite can be represented by left-angle J right-angle=σeE+χeEβ, where left-angle...right-angle represents spatial averages. The magnitude of the crossover field Ec, defined as the electric field at which the linear and nonlinear response of the composite become comparable, is found to have a power-law dependence Ec∼(pc-p)M(β), and the corresponding crossover current Ic is found to have similar dependence Ec∼(pc-p)W(β) as the percolation threshold is approached from below. By using a connection between the nonlinear response of the random nonlinear composite problem and the conductance fluctuation of the corresponding random linear composite problem the explicit expressions for M(β) and W(β) are calculated. We prove that both M(β) and W(β) are monotonically decreasing functions of β, which have the special values M(1+)=W(1+)=+∞, M(3)=[κ'(2)+s/2], W(3)=[κ'(2)-s/2], M(+∞)=(2-d)ν/2≤0, W(+∞)=-(s+ζG)/2c and the corresponding crossover current Ic are discussed as functions of β and some interesting crossover effects are reported. copyright 1996 The American Physical Society

  10. A pulsed magnetic field test facility for conductors and joints

    International Nuclear Information System (INIS)

    The International Thermonuclear Experimental Reactor (ITER) and, in the US, the Tokamak Physics Experiment (TPX) fusion programs both require conductor and joint testing in a pulsed magnetic background field in order to demonstrate that these components can operate successfully in a simulated, fusion-machine environment. Here, a pulsed magnetic field test facility is under construction at Massachusetts Institute of Technology for testing large scale cable-in-conduit superconductor and joint samples. Separate, demountable split-pair solenoid and saddle coils provide a combination of fields which can be either transverse of parallel to the sample axis. The solenoid and saddle magnets together can provide transverse peak fields as high as 8.4 T. Peak parallel fields of 6.6 T can be generated with the solenoid alone. Ramp-up rates of 1.5 T/s and ramp-down rates of 20 T/s are possible. Sample currents up to 50 kA are provided by a superconducting current transformer. The sample is connected to the transformer secondary through a pair of low resistance joints. Supercritical helium is provided to the sample at flow rates up to 20 g/s, pressures up to 1 MPa, and temperatures from 4.7 to 10 K. Programmable logic controllers provide coordination of the magnetic field, sample current, and helium flow rate and temperature in the sample. Sample and facility instrumentation signals are processed and data is stored on a workstation-based data acquisition system with comprehensive data reduction capability. Facility details and status are described

  11. Defects and properties of cadmium oxide based transparent conductors

    Science.gov (United States)

    Yu, Kin Man; Detert, D. M.; Chen, Guibin; Zhu, Wei; Liu, Chaoping; Grankowska, S.; Hsu, L.; Dubon, O. D.; Walukiewicz, Wladek

    2016-05-01

    Transparent conductors play an increasingly important role in a number of semiconductor technologies. This paper reports on the defects and properties of Cadmium Oxide, a transparent conducting oxide which can be potentially used for full spectrum photovoltaics. We carried out a systematic investigation on the effects of defects in CdO thin films undoped and intentionally doped with In and Ga under different deposition and annealing conditions. We found that at low growth temperatures (1 Ω cm due to incorporation of excess O in the form of O-related acceptor defects, likely to be O interstitials. Intentional doping with In and Ga donors leads to an increase of both the electron concentration and the mobility. With proper doping CdO films with electron concentration of more than 1021 cm-3 and electron mobility higher than 120 cm2/V s can be achieved. Thermal annealing of doped CdO films in N2 ambient can further improve the electrical properties by removing native acceptors and improving film crystallinity. Furthermore, the unique doping behavior and electrical properties of CdO were explored via simulations based on the amphoteric defect model. A comparison of the calculations and experimental results show that the formation energy of native donors and acceptors at the Fermi stabilization energy is ˜1 eV and that the mobility of sputtered deposited CdO is limited by a background acceptor concentration of ˜5-6 × 1020/cm3. The calculations offer an insight into understanding of the effects of defects on electrical properties of undoped and doped CdO and offer a potential to use similar methods to analyze doping and defect properties of other semiconductor materials.

  12. DUAL BAND MONOPOLE ANTENNA DESIGN

    Directory of Open Access Journals (Sweden)

    P. Jithu

    2013-06-01

    Full Text Available The WLAN and Bluetooth applications become popular in mobile devices, integrating GSM and ISM bands operation in one compact antenna, can reduce the size of mobile devices. Recently, lot many investigations are carried out in designing a dual band antennas with operating frequencies in GSM band and in ISM band for mobile devices. Printed monopoles are under this investigation. In this paper, dual-band printed monopoles are presented to operate at GSM band i.e. 900 MHz and ISM band i.e. 2.4 GHz. We intend to observe the antenna characteristics on the network analyzer and verify the theoretical results with the practical ones.

  13. Assessment of the noise annoyance among subway train conductors in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Mansoureh Hamidi

    2014-01-01

    Full Text Available Subway transportation system is a new phenomenon in Iran. Noise annoyance interferes with the individual′s task performance, and the required alertness in the driving of subway trains. This is the first study conducted to measure the level of noise and noise annoyance among conductors of subway organization in Tehran, Iran. This cross sectional study was conducted among 167 randomly selected train conductors. Information related to noise annoyance was collected by using a self-administered questionnaire. The dosimetry and sound metering was done for the conductors and inside the cabins. There were 41 sound metering measuring samples inside the conductors′ cabin, and there were 12 samples of conductors′ noise exposure. The results of sound level meter showed that the mean Leq was 73.0 dBA ± 8.7 dBA and the dosimetry mean measured Leq was 82.1 dBA ± 6.8 dBA. 80% of conductors were very annoyed/annoyed by noise in their work place. 53.9% of conductors reported that noise affected their work performance and 63.5% reported that noise causes that they lose their concentration. The noise related to movement of train wheels on rail was reported as the worst by 83.2% followed by the noise of brakes (74.3% and the ventilation noise (71.9%. 56.9% of conductors reported that they are suffering from sleeplessness, 40.1% from tinnitus and 80.2% feeling fatigue and sleepy. The study results showed the high level of noise and noise annoyance among train conductors and the poor health outcome of their exposure to this level of noise.

  14. Studies on advanced superconductors for fusion device. Pt. 1. Present status of Nb{sub 3}Sn conductors

    Energy Technology Data Exchange (ETDEWEB)

    Tachikawa, Kyoji; Yamamoto, Junya [eds.

    1996-03-01

    Nb{sub 3}Sn conductors have been developed with great expectation as an advanced high-field superconductor to be used in fusion devices of next generation. Furthermore, Nb{sub 3}Sn conductors are being developed for NMR magnet and superconducting generator as well as for cryogen-free superconducting magnet. A variety of fabrication procedures, such as bronze process, internal tin process and Nb tube method, have been developed based on the diffusion reaction. Recently, Nb{sub 3}Sn conductors with ultra-thin filaments have been fabricated for AC use. Both high-field and AC performances of Nb{sub 3}Sn conductors have been significantly improved by alloying addition. The Ti-doped Nb{sub 3}Sn conductor has generated 21.5T at 1.8K operation. This report summarizes manufacturing procedures, superconducting performances and applications of Nb{sub 3}Sn conductors fabricated through different processes in different countries. More detailed subjects included in this report are high-field properties, AC properties, conductors for fusion with large current capacities, stress-strain effect and irradiation effect as well as standardization of critical current measurement method regarding to Nb{sub 3}Sn conductors. Comprehensive grasp on the present status of Nb{sub 3}Sn conductors provided by this report will act as a useful data base for the future planning of fusion devices. (author). 172 refs.

  15. Band structures of carbon nanotube with spin-orbit coupling interaction

    Energy Technology Data Exchange (ETDEWEB)

    Liu Hong, E-mail: liuhong3@njnu.edu.c [Physics Department, Nanjing Normal University, Nanjing 210046 (China)

    2011-01-01

    We explore the band structures of single-walled carbon nanotubes (SWCNTs) with two types of spin-orbit couplings. The obtained results indicate that weak Rashba spin-orbit coupling interaction can lead to the breaking of four-fold degeneracy in all tubes even though without the intrinsic SO coupling. The asymmetric splitting between conduction bands and valence bands is caused by both SO couplings at the same time. When the ratio of Rashba spin-orbit coupling to the intrinsic spin-orbit coupling is larger than 3, metallic zigzag nanotube is always metallic conductor, on the contrary it becomes semiconducting properties. However, only when this ratio is equal to about 3 or the intrinsic spin-orbit coupling is much weak, the metallic armchair nanotube still holds the metallic behavior in transport.

  16. Global Evolutionary Algorithms in the Design of Electromagnetic Band Gap Structures with Suppressed Surface Waves Propagation

    Directory of Open Access Journals (Sweden)

    P. Kovacs

    2010-04-01

    Full Text Available The paper is focused on the automated design and optimization of electromagnetic band gap structures suppressing the propagation of surface waves. For the optimization, we use different global evolutionary algorithms like the genetic algorithm with the single-point crossover (GAs and the multi-point (GAm one, the differential evolution (DE and particle swarm optimization (PSO. The algorithms are mutually compared in terms of convergence velocity and accuracy. The developed technique is universal (applicable for any unit cell geometry. The method is based on the dispersion diagram calculation in CST Microwave Studio (CST MWS and optimization in Matlab. A design example of a mushroom structure with simultaneous electromagnetic band gap properties (EBG and the artificial magnetic conductor ones (AMC in the required frequency band is presented.

  17. Making the case for high temperature low sag (htls) overhead transmission line conductors

    Science.gov (United States)

    Banerjee, Koustubh

    The future grid will face challenges to meet an increased power demand by the consumers. Various solutions were studied to address this issue. One alternative to realize increased power flow in the grid is to use High Temperature Low Sag (HTLS) since it fulfills essential criteria of less sag and good material performance with temperature. HTLS conductors like Aluminum Conductor Composite Reinforced (ACCR) and Aluminum Conductor Carbon Composite (ACCC) are expected to face high operating temperatures of 150-200 degree Celsius in order to achieve the desired increased power flow. Therefore, it is imperative to characterize the material performance of these conductors with temperature. The work presented in this thesis addresses the characterization of carbon composite core based and metal matrix core based HTLS conductors. The thesis focuses on the study of variation of tensile strength of the carbon composite core with temperature and the level of temperature rise of the HTLS conductors due to fault currents cleared by backup protection. In this thesis, Dynamic Mechanical Analysis (DMA) was used to quantify the loss in storage modulus of carbon composite cores with temperature. It has been previously shown in literature that storage modulus is correlated to the tensile strength of the composite. Current temperature relationships of HTLS conductors were determined using the IEEE 738-2006 standard. Temperature rise of these conductors due to fault currents were also simulated. All simulations were performed using Microsoft Visual C++ suite. Tensile testing of metal matrix core was also performed. Results of DMA on carbon composite cores show that the storage modulus, hence tensile strength, decreases rapidly in the temperature range of intended use. DMA on composite cores subjected to heat treatment were conducted to investigate any changes in the variation of storage modulus curves. The experiments also indicates that carbon composites cores subjected to

  18. Keeping an Eye on the Conductor: Neural Correlates of Visuo-motor Synchronization and Musical Experience

    Directory of Open Access Journals (Sweden)

    Kentaro eOno

    2015-04-01

    Full Text Available For orchestra musicians, synchronized playing under a conductor’s direction is necessary to achieve optimal performance. Previous studies using simple auditory/visual stimuli have reported cortico-subcortical networks underlying synchronization and that training improves the accuracy of synchronization. However, it is unclear whether people who played regularly under a conductor and non-musicians activate the same networks when synchronizing with a conductor’s gestures. We conducted a functional magnetic resonance imaging (fMRI experiment testing nonmusicians and musicians who regularly play music under a conductor. Participants were required to tap the rhythm they perceived from silent movies displaying either conductor’s gestures or a swinging metronome. Musicians performed tapping under a conductor with more precision than nonmusicians. Results from fMRI measurement showed greater activity in the anterior part of the left superior frontal gyrus (SFG in musicians with more frequent practice under a conductor. Conversely, tapping with the metronome did not show any difference between musicians and nonmusicians, indicating that the expertise effect in tapping under the conductor does not result in a general increase in tapping performance for musicians. These results suggest that orchestra musicians have developed an advanced ability to predict conductor’s next action from the gestures.

  19. In-field critical current property of IBAD/PLD coated conductors

    International Nuclear Information System (INIS)

    REBa2Cu3Oy, (RE : rare earth elements, RE123) coated conductors are expected to show high performance in superconducting applications, due to their high mechanical strength and high current density in magnetic fields. Fujikura has developed ion-beam-assisted-deposition (IBAD) and pulsed-laser-deposition (PLD) technique, and today we routinely manufacture coated conductors with length over 500 m and Ic over 500 A/cm-width at 77 K, self field. We have also been able to fabricate long conductors with higher Ic by thickening RE123 layer. Although Ic performances at 77 K, self field are important, but performances in magnetic fields at lower temperatures below 77 K are more important for coil applications. In this work, we evaluated coated conductors with thick RE123 layer in magnetic fields at low temperatures. All samples are fabricated with long length. We measured samples by four-probe transport method at wide temperature range from 77 K to 10 K by using cryo-cooled cryostat. A conductor with 5.5 μm thick RE123 exhibits high Ic values of 937 A/cm-width at 77 K, self field, 637 A/cm-width at 50 K, 5 T and 976 A/cm-width at 40 K, 5 T.

  20. Free Molecular Heat Transfer Programs for Setup and Dynamic Updating the Conductors in Thermal Desktop

    Science.gov (United States)

    Malroy, Eric T.

    2007-01-01

    The programs, arrays and logic structure were developed to enable the dynamic update of conductors in thermal desktop. The MatLab program FMHTPRE.m processes the Thermal Desktop conductors and sets up the arrays. The user needs to manually copy portions of the output to different input regions in Thermal Desktop. Also, Fortran subroutines are provided that perform the actual updates to the conductors. The subroutines are setup for helium gas, but the equations can be modified for other gases. The maximum number of free molecular conductors allowed is 10,000 for a given radiation task. Additional radiation tasks for FMHT can be generated to account for more conductors. Modifications to the Fortran subroutines may be warranted, when the mode of heat transfer is in the mixed or continuum mode. The FMHT Thermal Desktop model should be activated by using the "Case Set Manager" once the model is setup. Careful setup of the model is needed to avoid excessive solve times.

  1. Diffuse interstellar absorption bands

    Institute of Scientific and Technical Information of China (English)

    XIANG FuYuan; LIANG ShunLin; LI AiGen

    2009-01-01

    The diffuse interstellar bands (DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s, the exact nature of DIBs still remains unclear. This article reviews the history of the detec-tions of DIBs in the Milky Way and external galaxies, the major observational characteristics of DIBs, the correlations or anti-correlations among DIBs or between DIBs and other interstellar features (e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise), and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

  2. Development of Low AC Loss TFA-MOD Coated Conductors

    Science.gov (United States)

    Katayama, K.; Machi, T.; Nakamura, T.; Takagi, Y.; Nakaoka, K.; Yoshizumi, M.; Izumi, T.; Shiohara, Y.

    TFA-MOD process is expected to be promising for future applications since it can produce high performance YBCO coated conductors (CCs) with low cost. Applying YBCO CCs to the power electric devices such as transformers and power cables, the reduction of alternating current (AC) loss for long wire is necessary. Multi-filamentation process, which is one of the most effective approaches for AC loss reduction, has been developed by the scribing process. We have developed the filamentation process using chemical etching. MOD derived CCs are, however, easily damaged in the chemical etching process due to existence of pores in a YBCO layer, resulting in critical current (Ic)-degradation and weak delamination strength. Consequently, it is difficult to scribe MOD derived CCs into 1mm-wide filaments for long length using the chemical etching process. Accordingly, we have studied a scribing process using an excimer laser without chemical etching. We defined P' value in this study as a function of irradiated laser power [J] divided by processing speed[m/s]. We studied relationship between the P' value and the results of scribing. It was found that we could scribe the C.C. with a sufficient depth in the condition of large P' value. Furthermore, we found that the Ic was degraded with further increase of the P' value. A 5 mm wide short sample was divided into 10 filaments by the excimer laser scribing process at the P' of 9[J/(m/s)]. The sample revealed reduction of the hysteresis loss down to 1/10 which could be expected from a theoretical prediction using the numbers of the filaments. Ic-degradation was suppressed as 28%, which was smaller than that of the scribed sample using chemical etching (Ic degradation was 38%). Subsequently, we applied the technique to a 100m long YBCO CC. The hysteresis loss of the 100m long MOD derived CC was reduced down to 1/10 (1/the number of filaments) after the multi-filamentation.

  3. Modelling ac ripple currents in HTS coated conductors

    Science.gov (United States)

    Xu, Zhihan; Grilli, Francesco

    2015-10-01

    Dc transmission using high temperature superconducting (HTS) coated conductors (CCs) offers a promising solution to the globally growing demand for effective, reliable and economic transmission of green energy up to the gigawatt level over very long distances. The credible estimation of the losses and thereby the heat dissipation involved, where ac ripples (introduced in rectification/ac-dc conversion) are viewed as a potential source of notable contribution, is highly essential for the rational design of practical HTS dc transmission cables and corresponding cryogenic systems to fulfil this demand. Here we report a targeted modelling study into the ac losses in a HTS CC subject to dc and ac ripple currents simultaneously, by solving Maxwell’s equations using the finite element method (FEM) in the commercial software package COMSOL. It is observed that the instantaneous loss exhibits only one peak per cycle in the HTS CC subject to sinusoidal ripples, given that the amplitude of the ac ripples is smaller than approximately 20% of that of the dc current. This is a distinct contrast to the usual observation of two peaks per cycle in a HTS CC subject to ac currents only. The unique mechanism is also revealed, which is directly associated with the finding that, around any local minima of the applied ac ripples, the critical state of -J c is never reached at the edges of the HTS CC, as it should be according to the Bean model. When running further into the longer term, it is discovered that the ac ripple loss of the HTS CC in full-wave rectification decays monotonically, at a speed which is found to be insensitive to the frequency of the applied ripples within our targeted situations, to a relatively low level of approximately 1.38 × 10-4 W m-1 in around 1.7 s. Comparison between this level and other typical loss contributions in a HTS dc cable implies that ac ripple currents in HTS CCs should only be considered as a minor source of dissipation in superconducting dc

  4. Uniaxial strain effects on transport properties of a supramolecular organic conductor θ-(DIETS)2[Au(CN)4

    International Nuclear Information System (INIS)

    Pressure-controlled switching between an insulating state and a superconducting state has been successfully realized on a supramolecular organic conductor θ-(DIETS)2[Au(CN)4] [DIETS = diiodo(ethylenedithio)diselenadithiafulvalene]. Strong contact between iodine on the donor (DIETS) molecule and nitrogen on the anion [Au(CN)4] genetates characteristic uniaxial strain effects on transport properties. Under the ambient pressure, the present system undergoes a semiconductor-insulator transition at 226 K. The effect of strains parallel to the conduction plane (ab-plane) is very small. Even under uniaxial strains up to 20 kbar along the a- and b-axis directions, the transition is not suppressed. Surprisingly, however, the c-axis strain induces a superconducting state with Tc of 8.6 K at 10 kbar. Band parameter calculation and the conductivity anisotropy ratio suggest that an increase in the bandwidth W associated with a c-axis strain transforms the system to the metallic and superconducting states. In the metallic state under c-axis strain, the temperature (T) dependence of the Hall coefficient (RH) and the Hall angle (θH) is expressed as RH ∝ T-1 and cotθH ∝ T2. (author)

  5. Shubnikov-de Haas Effect and Angular-Dependent Magnetoresistance in Layered Organic Conductor β''-(ET)(TCNQ)

    Science.gov (United States)

    Yasuzuka, Syuma; Uji, Shinya; Konoike, Takako; Terashima, Taichi; Graf, David; Choi, Eun Sang; Brooks, James S.; Yamamoto, Hiroshi M.; Kato, Reizo

    2016-08-01

    This paper reports the experimental results of the Shubnikov-de Haas (SdH) effect and angular-dependent magnetoresistance oscillation (AMRO) for the organic conductor β''-(ET)(TCNQ). We observed several two dimensional (2D) SdH frequencies, whose cross-sectional areas of the Fermi surfaces (FSs) correspond to only a few percent of the first Brillouin zone. Such small 2D FSs are not predicted by band-structure calculations, suggesting that these FS pockets are created by an imperfect nesting of FSs at low temperatures. It is found that the AMRO consists of a long-period oscillation and a short-period one. The long-period oscillation is associated with the Yamaji oscillation corresponding to the α orbit, whose shape and area are consistent with previous magneto-optical measurement. The short-period oscillation is not caused by peaks instead but dips. The dip structure is discussed in terms of the AMRO of a quasi-2D electron system with a periodic potential caused by the possible density-wave related to the ET layers or the 4kF charge-density-wave associated with the TCNQ layers.

  6. Design and Evaluation of Dual-Band Antennas Aimed for Contactless Health Monitoring Radar

    OpenAIRE

    Pandey, Gokarna; Soh, Ping Jack; Mercuri, Marco; Vandenbosch, Guy; Schreurs, Dominique

    2013-01-01

    This paper presents the evaluation of two antenna designs aimed for a Step Frequency Continuous Wave (SFCW) radar capable of non-invasive fall detection in a pseudo-static radar configuration. The performance of a dual-band rectangular planar monopole is compared against a conductor-backed coplanar waveguide (CBCPW) fed bowtie slot antenna in free space. Two elements of the better performing CBCPW fed bow-tie antenna are then combined, separated by a metal plate, and evaluated on the level of...

  7. A Compact Printed Monopole Antenna for Dual-band RFID and WLAN Applications

    OpenAIRE

    R. S. Kshetrimayum; Saladi, A. S. R.; J. R. Panda

    2011-01-01

    Design of a simple and compact microstrip-fed printed monopole antenna (PMA) for applications in wireless local area network (WLAN) and radio frequency identification (RFID) is presented. The dual-band operation is achieved from the 9-shaped folded antenna which is printed on a non-conductor backed dielectric. Measured percentage impedance bandwidth of the PMA at the center frequencies of 2.43 GHz and 5.24 GHz are 33.13 (2.14 GHz to 2.99 GHz) and 36.43 (4.40 GHz to 6.36 GHz) respectively. Con...

  8. Progress of long coated conductors fabrication with fluorine-free CSD method at SWJTU

    International Nuclear Information System (INIS)

    Highlights: • Recent progress on the long coated conductors fabrication by F-free CSD method is presented. • Single buffer and partial-melting technology and slot-die coating methods have been developed. • Reel-to-reel facilities for continuous process have been achieved. -- Abstract: Recent progress on the fabrication of long high-Tc superconducting coated conductors with a fluorine-free chemical solution deposition (CSD) method is presented. Developments including such novel methods as single buffer technology, partial-melting process on YBa2Cu3O7 (YBCO), slot-die coating and drying; reel-to-reel facilities for continuous process have been achieved in the effort on high-Tc superconducting coated conductors at SWJTU, which form a comprehensive technology to fabricate long coated tapes with high performances

  9. A 50 mm bore, 13 tesla superconducting magnet employing a prereacted multifilamentary Nb3Sn conductor

    International Nuclear Information System (INIS)

    Following the construction of two hybrid magnets, we intend to build up a third hybrid magnet which will produce about 30 T. A prereacted multifilamentary Nb3Sn conductor will be employed for the 12 T superconducting part of the hybrid. As a first step for the project, we have designed, constructed and tested a magnet which consists of 14 double-pancakes made of a prereacted multifilamentary Nb3Sn conductor and a back up coil made of a Nb-Ti conductor. The satisfactory results of the test on the magnet, in which we succeeded to produce 13.4 T, have given us very bright prospects for the 30 T hybrid magnet project

  10. Experimental study of the nonlinear diffusion of a magnetic field and skin explosion of cylindrical conductors

    Science.gov (United States)

    Chaikovsky, S. A.; Oreshkin, V. I.; Datsko, I. M.; Labetskaya, N. A.; Rybka, D. V.; Ratakhin, N. A.

    2015-11-01

    The paper presents the results of an experimental study of the skin explosion of cylindrical conductors of diameter 1-3 mm (copper, aluminum, titanium, steel 3, and stainless steel) at a peak magnetic field of 200-600 T. The experiments were carried out on the MIG pulsed power generator at a current of up to 2.5 MA and a current rise time of 100 ns. The surface explosion of a conductor was identified by the appearance of a flash of extreme ultraviolet radiation. A minimum magnetic induction has been determined below which no plasma is generated at the conductor surface. For copper, aluminum, steel 3, titanium, and stainless steel, the minimum magnetic induction has been estimated to be (to within 10%) 375, 270, 280, 220, and 245 T, respectively.

  11. Experimental study of the nonlinear diffusion of a magnetic field and skin explosion of cylindrical conductors

    Energy Technology Data Exchange (ETDEWEB)

    Chaikovsky, S. A.; Datsko, I. M.; Labetskaya, N. A.; Rybka, D. V.; Ratakhin, N. A. [Institute of High Current Electronics, SB, RAN, Tomsk (Russian Federation); Oreshkin, V. I. [Institute of High Current Electronics, SB, RAN, Tomsk (Russian Federation); Tomsk Polytechnic University, Tomsk (Russian Federation)

    2015-11-15

    The paper presents the results of an experimental study of the skin explosion of cylindrical conductors of diameter 1–3 mm (copper, aluminum, titanium, steel 3, and stainless steel) at a peak magnetic field of 200–600 T. The experiments were carried out on the MIG pulsed power generator at a current of up to 2.5 MA and a current rise time of 100 ns. The surface explosion of a conductor was identified by the appearance of a flash of extreme ultraviolet radiation. A minimum magnetic induction has been determined below which no plasma is generated at the conductor surface. For copper, aluminum, steel 3, titanium, and stainless steel, the minimum magnetic induction has been estimated to be (to within 10%) 375, 270, 280, 220, and 245 T, respectively.

  12. Printable elastic conductors with a high conductivity for electronic textile applications

    Science.gov (United States)

    Matsuhisa, Naoji; Kaltenbrunner, Martin; Yokota, Tomoyuki; Jinno, Hiroaki; Kuribara, Kazunori; Sekitani, Tsuyoshi; Someya, Takao

    2015-06-01

    The development of advanced flexible large-area electronics such as flexible displays and sensors will thrive on engineered functional ink formulations for printed electronics where the spontaneous arrangement of molecules aids the printing processes. Here we report a printable elastic conductor with a high initial conductivity of 738 S cm-1 and a record high conductivity of 182 S cm-1 when stretched to 215% strain. The elastic conductor ink is comprised of Ag flakes, a fluorine rubber and a fluorine surfactant. The fluorine surfactant constitutes a key component which directs the formation of surface-localized conductive networks in the printed elastic conductor, leading to a high conductivity and stretchability. We demonstrate the feasibility of our inks by fabricating a stretchable organic transistor active matrix on a rubbery stretchability-gradient substrate with unimpaired functionality when stretched to 110%, and a wearable electromyogram sensor printed onto a textile garment.

  13. Insulated conductor temperature limited heater for subsurface heating coupled in a three-phase WYE configuration

    Science.gov (United States)

    Vinegar, Harold J.; Sandberg, Chester Ledlie

    2010-11-09

    A heating system for a subsurface formation is described. The heating system includes a first heater, a second heater, and a third heater placed in an opening in the subsurface formation. Each heater includes: an electrical conductor; an insulation layer at least partially surrounding the electrical conductor; and an electrically conductive sheath at least partially surrounding the insulation layer. The electrical conductor is electrically coupled to the sheath at a lower end portion of the heater. The lower end portion is the portion of the heater distal from a surface of the opening. The first heater, the second heater, and the third heater are electrically coupled at the lower end portions of the heaters. The first heater, the second heater, and the third heater are configured to be electrically coupled in a three-phase wye configuration.

  14. Status of high temperature superconductor based magnets and the conductors they depend upon

    CERN Document Server

    Schwartz, J; Chan, W K; Gou, X F; Liu, X T; Phillips, M; Le, Q V; Naderi, G; Turenne, M; Ye, L

    2011-01-01

    This paper reviews the status of high temperature superconductors for high field magnets for future devices such as a high energy LHC or a muon collider. Some of the primary challenges faced for the implementation of systems are discussed. Two conductor technologies, Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ and YBa$_2$Cu$_3$O$_{7-\\delta}$, have emerged as high field conductor options, but their relative advantages and disadvantages for high field magnets are quite different. These are reviewed from an engineering perspective, including coil manufacturing, electromechanical behaviour and quench behaviour. Lastly, the important roles of "system pull" upon conductor and magnet technology development, and of interactions between the materials and magnet communities for accelerating development, are discussed.

  15. Transport IV characterisation of MgB2 conductor at a bend radius of 50 mm

    International Nuclear Information System (INIS)

    Performance of state of the art MgB2 multifilamentary conductor at a required bend radius is essential for many applications including but not limited to magnets and motors. The characterisation is generally done with benchmark transport Ic but further detail can be seen in IV characteristics which are undertaken in this paper. Two conductors with the same architecture but different diameters, 0.89 and 0.45 mm were measured from 32 K to 20 K in self-field in conditions of as received and deformed to a 50 mm bend diameter, corresponding to strains of 1.4 % and 0.7 % respectively. The qualifying 0.45 mm conductor was further measured in background fields up to 3 T. The smaller diameter wire was found to have no signs of degradation of critical behaviour in Ic or IV characteristics.

  16. Anomalous low field magnetization in fine filament NbTi conductors

    International Nuclear Information System (INIS)

    The first cable conductors for SSC were made with NbTi filaments whose diameters were in the 18 to 23 micron range. In an effort to reduce the magnetization effects in accelerator dipoles resulting from these large filaments, second generation conductors are now being manufactured with much smaller filaments. As part of this development a series of NbTi conductors were made with filament diameters ranging from 8.0 to 2.8 μm and having an average interfilament spacing of approximately 12% of filament diameter. Measurements at 4.3 K show that as the filament spacing decreases below a certain critical value the low field magnetization increases rapidly. This increase is seen to be strong function of interfilament distance, magnetic field and temperature. Details of these measurements and its implication for practical high current SSC wire design are discussed

  17. Effects of alloying on the strain response of critical currents in Nb3Sn conductors

    International Nuclear Information System (INIS)

    The critical current, I/sub c/, of bronze-processed Nb3Sn conductors vary when the conductors are mechanically strained in tension or compression. The variations in I/sub c/ are reversible until the strains are large enough to cause cracking of the Nb3Sn compound. After cracking occurs the changes in I/sub c/ with strain are irreversible. The reversible and irreversible characteristics of I/sub c/ are influenced by alloy additions to the conductors. Alloy additions to both the bronze matrix and the filament core are examined from the standpoint of their effects on the reversible and irreversible changes. Interpretation is based on our present understanding of the micromechanical aspects of these composite materials

  18. Noise generation mechanism. Coupling of normal and common modes in 3 conductor transmission line theory

    International Nuclear Information System (INIS)

    Common mode current of power supply, originating from commutation of switching rotation, flows through the earth, which is equivalent to the difference between 2 output currents. We point out that there is another source of electric noise, which causes strong induced electromotive forces on the earth. In order to understand the source of electric noise, we develop 3 conductor transmission line theory, based on a natural extension of principles of both electric and magnetic superposition. We obtain a new expression for coefficient of potential, which plays a vital role in construction of the 3 conductor transmission line theory. We point out that there appears a coupling of wave equations of normal and common modes in general geometrical configuration of 3 conductor lines. (author)

  19. Optimal Conductor Selection in Radial Distribution Systems for Productivity Improvement Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mahdi Mozaffari Legha

    2013-06-01

    Full Text Available Development of distribution systems result in higher system losses and poor voltage regulation. Consequently, an efficient and effective distribution system has become more urgent and important. Hence proper selection of conductors in the distribution system is important as it determines the current density and the resistance of the line. This paper examines the use of different evolutionary algorithms, genetic algorithm (GA, to optimal branch conductor selection in planning radial distribution systems with the objective to minimize the overall cost of annual energy losses and depreciation on the cost of conductors and reliability in order to improve productivity. Furthermore, The Backward-Forward sweep iterative method was adopted to solve the radial load flow analysis. Simulations are carried out on 69-bus radial distribution network using GA approach in order to show the accuracy as well as the efficiency of the proposed solution technique.

  20. Stray current interaction in the system of two extensive underground conductors

    International Nuclear Information System (INIS)

    The important problem, technically, is to evaluate the harmful effects that an electrified railway has on nearby earth-return circuits (cables, pipelines). This paper considers the effects of a DC-electrified railway system on two extensive metal conductors buried in parallel in the vicinity of the tracks. The interaction between currents flowing in both underground conductors is taken into account, whereas the reaction of the conductors' currents on the track current is disregarded. The analysis given is applicable to any DC railway system in which tracks may be represented by a single earth return circuit with current energization. It is assumed in the paper that the system considered is linear and that the earth is homogeneous. The technical application of the method is illustrated by an example of computer simulation

  1. Simultaneously bending and tensile strain effect on critical current in YBCO coated conductors

    International Nuclear Information System (INIS)

    YBCO coated conductors have been expected for the application to a coil for superconducting magnetic energy storage (SMES). In the application to a superconducting coil, the coated conductors experience bending, uniaxial tensile strain and their combined strain. Therefore, the influence of simultaneous bending and tensile strain on critical current should be revealed. In this work, we developed the test method of critical current under such combined strain state. As a result, it was confirmed that compressive pre-bending can improve the stress tolerance of the YBCO coated conductors. On the other hand, compressive bending strain suppresses the initial critical current by the intrinsic strain effect. These results indicate that optimal bending radius should be selected in order to realize superior stress tolerance and high current capacity simultaneously

  2. Stabilizing effect of passive conductors with arbitrary shape for positional instabilities

    International Nuclear Information System (INIS)

    For positional instabilities in the tokamak, the stabilizing index nsub(s) is an adequate parameter to characterize the stabilizing effect produced by several kinds of passive conductors around a plasma column such as vacuum vessel and poloidal field coils. Since a system of passive conductors with arbitrary shape can be involved into multiple L-R circuits, this parameter nsub(s) of those passive conductors is expressed in a simple form by using a method of the eigen mode expansion of multiple L-R circuits. This parameter nsub(s) is very useful to estimate not only a growth rate of positional instability and its feedback stabilization but also an inward shift of plasma column due to a minor disruption. (author)

  3. Progress of long coated conductors fabrication with fluorine-free CSD method at SWJTU

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Y., E-mail: yzhao@swjtu.edu.cn [Key Lab of Advanced Materials Technologies, Key Lab of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education), Superconductivity and New Energy Center (SNEC), Southwest Jiaotong University, Chengdu 610031 (China); School of Materials Science and Engineering, University of New South Wales, Sydney 2052, NSW (Australia); Wang, W.T.; Lei, M.; Pu, M.H.; Zhang, Y. [Key Lab of Advanced Materials Technologies, Key Lab of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education), Superconductivity and New Energy Center (SNEC), Southwest Jiaotong University, Chengdu 610031 (China); Cheng, C.H. [School of Materials Science and Engineering, University of New South Wales, Sydney 2052, NSW (Australia)

    2013-10-15

    Highlights: • Recent progress on the long coated conductors fabrication by F-free CSD method is presented. • Single buffer and partial-melting technology and slot-die coating methods have been developed. • Reel-to-reel facilities for continuous process have been achieved. -- Abstract: Recent progress on the fabrication of long high-T{sub c} superconducting coated conductors with a fluorine-free chemical solution deposition (CSD) method is presented. Developments including such novel methods as single buffer technology, partial-melting process on YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO), slot-die coating and drying; reel-to-reel facilities for continuous process have been achieved in the effort on high-T{sub c} superconducting coated conductors at SWJTU, which form a comprehensive technology to fabricate long coated tapes with high performances.

  4. Analysis of Conductor Displacements in the Coil of the LHC Main Dipole by Speckle Interferometry

    CERN Document Server

    Ferracin, P; Scandale, Walter; Todesco, Ezio; Tropea, P

    2002-01-01

    Magnetic field quality in superconducting magnets mostly depends on conductor position in operational conditions (under pressure, at 1.9 K). For the case of the LHC main magnets, the conductor layout must agree with the nominal design within less than 0.05 mm to met the field quality specifications. Finite element models are a numerical tool to forecast loads and deformations of mechanical structures, and can be used to evaluate conductor displacements. To verify the FEM response at room temperature, we made displacement measurements using speckle interferometer on a short sample of the dipole coils. Experimental results are compared with the numerical calculations, allowing a stringent test of the most critical features of the FEM (interfaces between different materials and coil properties).

  5. The Conductor As Visual Guide: Gesture and Perception of Musical Content.

    Science.gov (United States)

    Kumar, Anita B; Morrison, Steven J

    2016-01-01

    Ensemble conductors are often described as embodying the music. Researchers have determined that expressive gestures affect viewers' perceptions of conducted ensemble performances. This effect may be due, in part, to conductor gesture delineating and amplifying specific expressive aspects of music performances. The purpose of the present study was to determine if conductor gesture affected observers' focus of attention to contrasting aspects of ensemble performances. Audio recordings of two different music excerpts featuring two-part counterpoint (an ostinato paired with a lyric melody, and long chord tones paired with rhythmic interjections) were paired with video of two conductors. Each conductor used gesture appropriate to one or the other musical element (e.g., connected and flowing or detached and crisp) for a total of sixteen videos. Musician participants evaluated 8 of the excerpts for Articulation, Rhythm, Style, and Phrasing using four 10-point differential scales anchored by descriptive terms (e.g., disconnected to connected, and angular to flowing.) Results indicated a relationship between gesture and listeners' evaluations of musical content. Listeners appear to be sensitive to the manner in which a conductor's gesture delineates musical lines, particularly as an indication of overall articulation and style. This effect was observed for the lyric melody and ostinato excerpt, but not for the chords and interjections excerpt. Therefore, this effect appears to be mitigated by the congruence of gesture to preconceptions of the importance of melodic over rhythmic material, of certain instrument timbres over others, and of length between onsets of active material. These results add to a body of literature that supports the importance of the visual component in the multimodal experience of music performance. PMID:27458425

  6. Effect of conductor geometry on source localization: Implications for epilepsy studies

    Energy Technology Data Exchange (ETDEWEB)

    Schlitt, H.; Heller, L.; Best, E.; Ranken, D.; Aaron, R.

    1994-07-01

    We shall discuss the effects of conductor geometry on source localization for applications in epilepsy studies. The most popular conductor model for clinical MEG studies is a homogeneous sphere. However, several studies have indicated that a sphere is a poor model for the head when the sources are deep, as is the case for epileptic foci in the mesial temporal lobe. We believe that replacing the spherical model with a more realistic one in the inverse fitting procedure will improve the accuracy of localizing epileptic sources. In order to include a realistic head model in the inverse problem, we must first solve the forward problem for the realistic conductor geometry. We create a conductor geometry model from MR images, and then solve the forward problem via a boundary integral equation for the electric potential due to a specified primary source. One the electric potential is known, the magnetic field can be calculated directly. The most time-intensive part of the problem is generating the conductor model; fortunately, this needs to be done only once for each patient. It takes little time to change the primary current and calculate a new magnetic field for use in the inverse fitting procedure. We present the results of a series of computer simulations in which we investigate the localization accuracy due to replacing the spherical model with the realistic head model in the inverse fitting procedure. The data to be fit consist of a computer generated magnetic field due to a known current dipole in a realistic head model, with added noise. We compare the localization errors when this field is fit using a spherical model to the fit using a realistic head model. Using a spherical model is comparable to what is usually done when localizing epileptic sources in humans, where the conductor model used in the inverse fitting procedure does not correspond to the actual head.

  7. Effect of conductor geometry on source localization: Implications for epilepsy studies

    International Nuclear Information System (INIS)

    We shall discuss the effects of conductor geometry on source localization for applications in epilepsy studies. The most popular conductor model for clinical MEG studies is a homogeneous sphere. However, several studies have indicated that a sphere is a poor model for the head when the sources are deep, as is the case for epileptic foci in the mesial temporal lobe. We believe that replacing the spherical model with a more realistic one in the inverse fitting procedure will improve the accuracy of localizing epileptic sources. In order to include a realistic head model in the inverse problem, we must first solve the forward problem for the realistic conductor geometry. We create a conductor geometry model from MR images, and then solve the forward problem via a boundary integral equation for the electric potential due to a specified primary source. One the electric potential is known, the magnetic field can be calculated directly. The most time-intensive part of the problem is generating the conductor model; fortunately, this needs to be done only once for each patient. It takes little time to change the primary current and calculate a new magnetic field for use in the inverse fitting procedure. We present the results of a series of computer simulations in which we investigate the localization accuracy due to replacing the spherical model with the realistic head model in the inverse fitting procedure. The data to be fit consist of a computer generated magnetic field due to a known current dipole in a realistic head model, with added noise. We compare the localization errors when this field is fit using a spherical model to the fit using a realistic head model. Using a spherical model is comparable to what is usually done when localizing epileptic sources in humans, where the conductor model used in the inverse fitting procedure does not correspond to the actual head

  8. Analysis of Conductor Impedances Accounting for Skin Effect and Nonlinear Permeability

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, M P; Ong, M M; Brown, C G; Speer, R D

    2011-07-20

    It is often necessary to protect sensitive electrical equipment from pulsed electric and magnetic fields. To accomplish this electromagnetic shielding structures similar to Faraday Cages are often implemented. If the equipment is inside a facility that has been reinforced with rebar, the rebar can be used as part of a lighting protection system. Unfortunately, such shields are not perfect and allow electromagnetic fields to be created inside due to discontinuities in the structure, penetrations, and finite conductivity of the shield. In order to perform an analysis of such a structure it is important to first determine the effect of the finite impedance of the conductors used in the shield. In this paper we will discuss the impedances of different cylindrical conductors in the time domain. For a time varying pulse the currents created in the conductor will have different spectral components, which will affect the current density due to skin effects. Many construction materials use iron and different types of steels that have a nonlinear permeability. The nonlinear material can have an effect on the impedance of the conductor depending on the B-H curve. Although closed form solutions exist for the impedances of cylindrical conductors made of linear materials, computational techniques are needed for nonlinear materials. Simulations of such impedances are often technically challenging due to the need for a computational mesh to be able to resolve the skin depths for the different spectral components in the pulse. The results of such simulations in the time domain will be shown and used to determine the impedances of cylindrical conductors for lightning current pulses that have low frequency content.

  9. Lead Nanopowder as Advanced Semi-Conductor, An Insight

    CERN Document Server

    Theivasanthi, T

    2013-01-01

    This work reports aspect related to semi-conducting nature of nano-sized particles of lead. This attempt finds its semiconducting behaviors elaborately and such advanced insight has so far not been said in literatures. New findings of Pb nanopowder (metal) by optical, fluorescence, cyclic voltammetry and four probe studies are presented in this study. The successful calculations of band gap, resistance value confirm its semi-conducting nature and explore its potential application in various industries. This work throws some light on and helps further research.

  10. Nb/sub 3/Sn conductors for 12 Tesla toroidal field coils

    International Nuclear Information System (INIS)

    Several advanced multifilamentary Nb/sub 3/Sn conductors were examined for various modes of cooling for the 12 Tesla ETF application. Of these, a pancake-wound 15,000 amp flat cable of triplets of large strands in a perforated stainless steel channel was selected as the preferred candidate. This cable will be cold-end cryostable in a pool-boiling environment with a maximum heat transfer from the unoccluded strand surface of 0.24 w/cm/sup 2/. The construction of the conductor and coil is relatively simple, offering potential economies in quality assurance and production costs. 15 refs

  11. Exploración de la ansiedad en conductores noveles y profesionales

    OpenAIRE

    Sáiz Vicente, Enrique; Bañuls Egeda, Rosa; Monteagudo Soto, Mª José

    1997-01-01

    Este trabajo pone de manifiesto la importancia que tiene el estudio de los procesos emocionales y cognitivos-motivacionales en la actividad de conducir. Para ello se describen las muestras de conductores profesionales y noveles empleados en el trabajo y se realiza un análisis de las características de los mismos, así como un análisis factorial con las puntuaciones obtenidas en los items del cuestionario I.S.A.T. (Bañuls, 1993) para ambas muestras de conductores...

  12. Estudio de policonsumo en una muestra de conductores de bogota, año 2005

    OpenAIRE

    Sánchez Cardozo, Óscar Armando; González O., Jorge Oswaldo; Dominguez Márquez, Carolina; López Castro, Adriana

    2011-01-01

    Antecedentes. No conocemos estudios que establezcanen nuestro medio la dimensión del policonsumo en conductoresde vehículo automotor. El problema delpoliconsumo puede explicar en algunos casos la falta deconcordancia de alcoholemia, etilometria y examen clínico.En este informe queremos centrarnos en la presentaciónde policonsumo en la muestra y el cuadro clínico deestos conductores.Objetivo. Determinar en una muestra de conductores deBogotá, con sospecha de intoxicación etílica, el consumode ...

  13. A radiation method for variation of the insulator-conductor transition of polyethylene compositions

    International Nuclear Information System (INIS)

    A radiation method for controlled variation of the insulator-conductor transition of electroconductive polymeric materials, based on low density polyethylene (LDPE) compositions has been proposed. This method involves gamma rays (60Co)-irradiation of LDPE compositions filled with soot PM-120 type. The effect of the irradiation dose on the controlled steepness decrease of the insulator-conductor transition has been obtained. The dependences of tensile strength at break, elongation at break, differential Young's modulus and Vicat softening point of LDPE compositions on the irradiation dose has been established. (author)

  14. Spectroscopy of charge transfer complexes of four amino acids as organic two-dimensional conductors

    Energy Technology Data Exchange (ETDEWEB)

    Padhiyar, Ashvin; Patel, A J; Oza, A T [Department of Physics, Sardar Patel University, Vallabh Vidyanagar-388 120, Gujarat (India)

    2007-12-05

    It is found in this study that four amino acids, namely asparagine, arginine, histidine and glutamine form two-dimensional conducting systems which are charge transfer complexes (CTCs) with organic acceptors like TCNQ, TCNE, chloranil, DDQ, TNF and iodine. It is verified using optical absorption edges that these are 2d conductors like transition metal dichalcogenides obeying absorption functions different from 1d and 3d conductors. This 2d nature is related to the network of intermolecular H-bonding in these complexes, which leads to a global H-bonded network resulting in the absence of local deformation due to the relaxation of strain.

  15. Anomalous temperature dependency of the Anderson-Grüneisen parameters in high ionic conductors

    International Nuclear Information System (INIS)

    The Anderson-Grüneisen (AG) parameter carries information on the anharmonicity of the atomic vibrations of the materials. Therefore, its study is expected to provide useful insights to understand the ion transport properties in solids. However, few attentions on the AG parameter of ionic conductors have been paid till now. In the present paper, a comparative study on the temperature dependence of the AG parameter in superionic materials and other crystals is presented. It is shown that the AG parameter of superionic materials exhibit anomalously large temperature dependencies. The relations of this finding with the material properties of ionic conductors are briefly discussed.

  16. LA IMPORTANCIA DE LA VALORACIÓN DEL TRABAJO EN UN GRUPO DE CONDUCTORES DE CARGA

    OpenAIRE

    Mireya Zamora Macorra; María Adriana Cecilia Cruz Flores

    2012-01-01

    El objetivo del siguiente trabajo fue determinar el efecto del apoyo social, la satisfacción laboral y el control sobre el trabajo en la salud de un grupo de conductores federales de carga. Para ello, se encuestó a 119 conductores de las bases de cuatro ciudades mexicanas, quienes trasladaban combustible al sur y centro del país. Se aplicaron algunas secciones de la encuesta individual del Programa de Evaluación y Seguimiento de la Salud de los Trabajadores, identificándose la relación entre ...

  17. The CMS Magnet Commissioning and the Development of an Improved CMS Conductor Suitable for Future Proposals

    CERN Document Server

    Campi, D; Gaddi, A; Gerwig, H; Hervé, A; Sgobba, S; Fabbricatore, P; Kircher, F

    2008-01-01

    The success of the CMS Magnet commissioning has clearly shown the reliability of the conceptual choices for the cold mass. The reinforced conductor and the multi layer winding open the path for the conception of Large Magnet for HEP of the next generation. The paper will report about the basic results of the test campaign and then, after some critical considerations about the choices made for the CMS coil construction, possible improvements for the conductor construction are outlined. The main goal being to preserve long term RRR, and thus stability, of the insert and simplify the welding process to join the reinforcement alloy to the insert.

  18. Artificial Perfect Electric Conductor-Perfect Magnetic Conductor Anisotropic Metasurface for Generating Orbital Angular Momentum of Microwave with Nearly Perfect Conversion Efficiency

    CERN Document Server

    Chen, Menglin L N; Sha, Wei E I

    2016-01-01

    Orbital angular momentum (OAM) is a promising degree of freedom for fundamental studies in electromagnetics and quantum mechanics. The unlimited state space of OAM shows a great potential to enhance channel capacities of classical and quantum communications. By exploring the Pancharatnam-Berry phase concept and engineering anisotropic scatterers in a metasurface with spatially varying orientations, a plane wave with zero OAM can be converted to a vortex beam carrying nonzero OAM. In this paper, we proposed two types of novel PEC (perfect electric conductor)-PMC (perfect magnetic conductor) anisotropic metasurfaces. One is composed of azimuthally continuous loops and the other is constructed by azimuthally discontinuous dipole scatterers. Both types of metasurfaces are mounted on a mushroom-type high impedance surface. Compared to previous metasurface designs for generating OAM, the proposed ones achieve nearly perfect conversion efficiency. In view of the eliminated vertical component of electric field, the c...

  19. Japanese efforts on coated conductor processing and its power applications: New 5 year project for materials and power applications of coated conductors (M-PACC)

    Science.gov (United States)

    Shiohara, Y.; Fujiwara, N.; Hayashi, H.; Nagaya, S.; Izumi, T.; Yoshizumi, M.

    2009-10-01

    Five years of Japanese national project (FY2003-FY2007) was ended last spring with remarkable success. The national project was originally aimed for development of coated conductors which have high superconductivity performance and long length enough to fabricate high temperature superconducting (HTS) electric power devices. Preliminary research and development of HTS electric power devices were carried out as well. A series of R&D results will be summarized and reviewed in this paper. The new 5 years Japanese national project has started last June (FY2008-FY2012) to develop HTS electric power applications including SMES, cables and transformers and to develop/produce coated conductors satisfying the requirements from the respective power devices. Collaborative R&D efforts by national laboratories, universities and private companies have been started with the supports of NEDO and METI. The accomplishment of the previous project will be summarized and the plans and goals of the new project will be presented in this paper.

  20. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  1. Measurement of local critical currents in TFA-MOD processed coated conductors by use of scanning Hall-probe microscopy

    International Nuclear Information System (INIS)

    We have investigated 2-dimensional distribution of critical current density. We have measured TFA-MOD processed YBCO coated conductor. We used scanning Hall-probe microscopy. These provided information is useful for fabrication process of coated conductor. We have carried out 2-dimensional (2D) measurement of local critical current in a Trifluoroacetates-Metal Organic Deposition (TFA-MOD) processed YBCO coated conductor using scanning Hall-probe microscopy. Recently, remarkable R and D accomplishments on the fabrication processes of coated conductors have been conducted extensively and reported. The TFA-MOD process has been expected as an attractive process to produce coated conductors with high performance at a low production cost due to a simple process using non-vacuum equipments. On the other hand, enhancement of critical currents and homogenization of the critical current distribution in the coated conductors are definitely very important for practical applications. According to our measurements, we can detect positions and spatial distribution of defects in the conductor. This kind of information will be very helpful for the improvement of the TFA-MOD process and for the design of the conductor intended for practical electric power device applications.

  2. The effect of Ti conduit on the critical current in (Nb,Ti)3Sn cable-in-conduit conductors

    International Nuclear Information System (INIS)

    The effect of titanium conduit on the critical current in (Nb,Ti)3Sn cable-in-conduit conductors was investigated to obtain a high performance conductor which would be applied to large superconducting magnets such as those for fusion machines. Titanium has equivalent thermal contraction coefficient to that of (Nb,Ti)3Sn filaments, and it is expected by using titanium as the conduit to suppress degradation of critical current due to excess thermal prestrain on (Nb,Ti)3Sn filaments. Some titanium conduit sample conductors were made, and thier critical current performance were measured together with some stainless steel (SUS316) and copper-nickel alloy (Cu-10Ni) conduit conductors. The experimental results indicated that the titanium conduit conductors had no critical current degradation due to thermal strain, whereas the stainless steel and copper-nickel alloy conduit conductors showed remarkable degradation on thier critical current performance and greater degradation was observed with smaller void conductor. In conclusion, titanium is verified to be excellent conduit material for (Nb,Ti)3Sn cable-in-conduit conductors. (author)

  3. Technology development and mass production of Nb3Sn conductors for ITER toroidal field coils in Japan

    International Nuclear Information System (INIS)

    The design and manufacture of Nb3Sn conductors for ITER toroidal field (TF) coils have many technical challenges. Although it was demonstrated in the ITER model coil project that the conductors have a sufficiently high performance and the engineering design is valid, unexpected issues arose. Through both theoretical and experimental efforts improved conductors were developed. The Japan Atomic Energy Agency started to procure improved conductors for TF coils as part of the ITER project. Because the required tonnage of Nb3Sn strands is quite large compared with past experience and the required superconducting performance is higher than that of the model coils, quality control techniques are very important for the successful manufacture of the strands. Approximately 60 ton of Nb3Sn strands have been successfully completed under a severe quality control regimen and all strands meet ITER specifications. This paper summarizes the technical developments leading to the first successful mass production of ITER TF conductors.

  4. Fabrication of the Textured Ni-9.3at.%W Alloy Substrate for Coated Conductors

    DEFF Research Database (Denmark)

    Gao, M. M.; Suo, H. L.; Grivel, Jean-Claude;

    2011-01-01

    It is difficult to obtain a sharp cube texture in the Ni-9.3at.% W substrate used for coated conductors due to its low stacking fault energy. In this paper, the traditional cold rolling procedure was optimized by introducing an intermediate recovery annealing. The deformation texture has been imp...

  5. Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic proton conductors

    DEFF Research Database (Denmark)

    He, Ronghuan; Qingfeng, Li; Gang, Xiao;

    2003-01-01

    Phosphoric acid doped polybenzimidazole (PBI) and PBI composite membranes have been prepared in the present work. The PBI composites contain inorganic proton conductors including zirconium phosphate (ZrP), (Zr(HPO4)2·nH2O), phosphotungstic acid (PWA), (H3PW12O40·nH2O) and silicotungstic acid (Si...

  6. Electrical characteristics for full size NbTi cable in conduit conductor

    International Nuclear Information System (INIS)

    In the framework of the design of the ITER poloidal field magnet conductor, the testing of a full size, short length NbTi conductor has been performed at the Sultan facility. The conductor is composed of 2 straight parallel legs with a copper joint between them at one extremity. The legs are based on different strands, Ni plated the first, CuNi internal barrier the second. The system is fully instrumented, in particular several voltage taps and thermometers measure the conductor behaviour and allow to follow the superconducting / normal transition. From the experimental results it is possible to deduce the different current threshold values for the stable/unstable transition for each of the 2 legs. The values are about 24 kA for the left leg and 35 kA for the right leg (corresponding respectively to 115 A/mm2 and 165 A/mm2 of superconducting area current density). The n factor has a square root dependence with respect to Jc, showing in any cases values in the range expected from strand data. Changes in voltage steepness during steady state current ramp up show a change in jacket-strand resistance with cycling

  7. Modelling of Temperature-Dependent Effective Impedance of Nonferromagnetic Massive Conductor

    Czech Academy of Sciences Publication Activity Database

    Doležel, Ivo; Musil, Ladislav; Ulrych, B.

    Cornwall: Springer, 2005 - (Wiak, S.; Krawczyk, A.; Trlep, M.), s. 273-278 ISBN 1-4020-3168-8 R&D Projects: GA ČR(CZ) GA102/01/1401 Institutional research plan: CEZ:AV0Z20570509 Keywords : temperature-dependent effective impedance * non-ferromagnetic massive conductor Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  8. Effect of transverse load on the critical current of a coated conductor Roebel cable

    International Nuclear Information System (INIS)

    Roebel cables are one possible option for use in the manufacture of high current conductors for various technical applications. In this work the behaviour of critical current under transverse loads up to 90 MPa was studied in coated conductor Roebel cables. First the critical current evolution under transverse load was measured on 4 mm wide coated conductor tapes with Hastelloy substrate (copper surround stabilizer) and on punched tapes, which are used for the assembling of Roebel cables. It was found that they were able to withstand large transverse loads (>100 MPa) with less than 2% degradation of the critical current at 77 K. In contrast, with tapes, a significant reduction of the critical current (>20%) was observed in Roebel cable samples at pressure as low as 10 MPa. Marks of mechanical defects were observed in the strands extracted from the cable. Measurements of the local critical current on extracted strands confirmed that in the regions which were visually damaged the critical current was also reduced. The defects are attributed to pinching (stress concentration), which takes place in the cable. The results suggest that the integration of coated conductor Roebel cables into large systems should be carefully evaluated. (paper)

  9. Simplified Calculation of Maximum Conductor Tension at Two Stages of Their Movement During Short Circuit

    Directory of Open Access Journals (Sweden)

    I. I. Serguei

    2006-01-01

    Full Text Available The paper contains formulae of the simplified calculation of maximum conductor tension at stages of their movement during short circuit. Assurance estimation of the simplified calculation is done on the basis of the experimental data and calculative experiment. Correction factors for higher accuracy of the simplified calculation are proposed in the paper.

  10. Simplified Calculation of Maximum Conductor Tension at Two Stages of Their Movement During Short Circuit

    OpenAIRE

    I. I. Serguei; A. P. Androukevich; Е. G. Ponomarenko

    2006-01-01

    The paper contains formulae of the simplified calculation of maximum conductor tension at stages of their movement during short circuit. Assurance estimation of the simplified calculation is done on the basis of the experimental data and calculative experiment. Correction factors for higher accuracy of the simplified calculation are proposed in the paper.

  11. Short-circuit experiments on a high Tc-superconducting cable conductor

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Jensen, E.H.; Traholt, C.

    2002-01-01

    A high temperature superconductor (HTS) cable conductor (CC) with a critical current of 2.1 kA was tested over a range of short-circuit currents up to 20 kA. The duration of the short-circuit currents is 1 s. Between each short-circuit test the critical current of the HTS CC was measured in order...

  12. Group Cohesion, Collective Efficacy, and Motivational Climate As Predictors of Conductor Support in Music Ensembles

    Science.gov (United States)

    Matthews, Wendy K.; Kitsantas, Anastasia

    2007-01-01

    In the present study, we examined whether collective efficacy, group cohesion (task and social), and perceived motivational climate (task-involving and ego-involving orientations) in a music ensemble predict instrumentalists' perceived conductor support. Ninety-one (N = 91) skilled high school instrumentalists participated in the study. To assess…

  13. Development of cube textured Ni-W alloy substrates used for coated conductors

    DEFF Research Database (Denmark)

    Suo, Hongli; Ma, Lin; Gao, Mangmang;

    2014-01-01

    It is considered as a challenge for RABiTS route to get cube textured Ni-W alloy substrates with high mechanical and magnetic properties for coated conductors. The works of our group in recent years are summarized about different Ni-W substrates with high W content and composite tapes made by RABi...

  14. Selective Laser Direct Patterning of Silver Nanowire Percolation Network Transparent Conductor for Capacitive Touch Panel.

    Science.gov (United States)

    Hong, Sukjoon; Yeo, Junyeob; Lee, Jinhwan; Lee, Habeom; Lee, Phillip; Lee, Seung S; Ko, Seung Hwan

    2015-03-01

    We introduce a facile method to enhance the functionality of a patterned metallic transparent conductor through selective laser ablation of metal nanowire percolation network. By scanning focused nanosecond pulsed laser on silver nanowire percolation network, silver nanowires are selectively ablated and patterned without using any conventional chemical etching or photolithography steps. Various arbitrary patterns of silver nanowire transparent conductors are readily created on the percolation network by changing various laser parameters such as repetition rate and power. The macroscopic optical and electrical properties of the percolation network transparent conductor can be easily tuned by changing the conductor pattern design via digital selective laser ablation. Further investigation on the silver nanowire based electrode line prepared by the ablation process substantiates that the general relation for a conducting thin film fails at a narrow width, which should be considered for the applications that requires a high resolution patterns. Finally, as a proof of concept, a capacitive touch sensor with diamond patterns has been demonstrated by selective laser ablation of metal nanowire percolation network. PMID:26413659

  15. Electron and phonon drag in thermoelectric transport through coherent molecular conductors

    DEFF Research Database (Denmark)

    Lü, Jing-Tao; Wang, Jian-Sheng; Hedegård, Per;

    2016-01-01

    We study thermoelectric transport through a coherent molecular conductor connected to two electron and two phonon baths using the nonequilibrium Green's function method. We focus on the mutual drag between electron and phonon transport as a result of ‘momentum’ transfer, which happens only when t...

  16. Quantitative computed tomography for objectifying disseminated skeletal muscles alterations in female conductors of progressive muscular dystrophy

    International Nuclear Information System (INIS)

    The detection of early morphologic changes, such as circumscribed infiltrations of adipose connective tissue into the muscles of female conductors of progressive muscular dystrophy requires quantitative planimetric methods. For a reliable interpretation of the results the dependence of the fat content of the musculature on age and physical constitution of the patient must be taken into consideration in each individual case. (author)

  17. Design study of coated conductor direct drive wind turbine generator for small scale demonstration

    DEFF Research Database (Denmark)

    Abrahamsen, Asger Bech; Jensen, Bogi Bech

    2012-01-01

    We have investigated the properties of a superconducting direct drive generator suitable for demonstration in a small scale 11 kW wind turbine. The engineering current density of the superconducting field windings is based on properties of coated conductors wound into coils holding of the order 6...

  18. CFD thermal modelling of Lynx overhead conductors in distribution networks with integrated Renewable Energy Driven Generators

    International Nuclear Information System (INIS)

    Results presented on application of a CFD technique for determination of the thermal state of a Lynx overhead conductor, used in power distribution networks. The thermal state of the Lynx conductor is mainly defined by the magnitude of the transmitted electrical current, ambient temperature, wind velocity and its direction and also by solar radiation. CFD modelling provides engineers with a capability to fully reflect in the process of numerical simulations variations of the above parameters over a range which is typical for real exploitation conditions. Results for both the steady-state and transient responses have been obtained and compared to those predicted by industrial standards and available from experimental data. Time constant values were obtained for various scenarios in which there was an instantaneous change in the magnitude of the electrical current or wind velocity. Analysis of numerical results demonstrate that the CFD technique provides an adequate level of accuracy in predicting the thermal state of the overhead conductor and could be a viable option for the dynamic analysis of distribution networks with a number of renewable energy generators, operating under varying electrical load and weather conditions. -- Highlights: • The thermal state of the Lynx overhead conductor was studied using CFD modelling. • Steady and transient thermal states were studied for a range of operating conditions. • CFD results were compared to that from industrial standards and experiments. • Time constant values were obtained for changes in the current and wind velocity

  19. EMF measurements on mixed protonic/electronic conductors for hydrogen membrane applications

    DEFF Research Database (Denmark)

    Bentzer, Henrik Karnøe; Bonanos, Nikolaos; Phair, John

    2010-01-01

    Electromotive force (EMF) measurements are often used to estimate the transport number of conducting species in ionic and mixed conductors. In this work, the applicability of the method to systems, where both protonic, oxide-ionic and electronic conduction is significant, was examined. The effect...

  20. Metal-free magnetic conductor substrates for placement-immune antenna assemblies

    Science.gov (United States)

    Eubanks, Travis Wayne; Loui, Hung; McDonald, Jacob Jeremiah

    2015-09-29

    A magnetic conductor substrate produced for mounting to an antenna includes a sheet of dielectric lattice material having a length, a width and a thickness that is less than the length and less than the width. Within the sheet of dielectric lattice material is disposed an array of dielectric elements.

  1. Charges on the surface of a lentil cavity in a two-dimensional homogeneous conductor

    Science.gov (United States)

    Batkin, V. I.

    2010-09-01

    The linear charge density on arc segments of a lentil cavity in a two-dimensional homogeneous conductor in a uniform external electric field is determined analytically. A singularity of the current density on the edges of the segments makes the resultant relations a helpful test for numerical computational algorithms.

  2. Analytical investigation in bending characteristic of twisted stacked-tape cable conductor

    Science.gov (United States)

    Takayasu, Makoto; Chiesa, Luisa

    2015-12-01

    An analytical model to evaluate bending strains of a twisted stack-tape cable (TSTC) conductor has been developed. Through a comparison with experimental results obtained for a soldered 32-tape YBCO TSTC conductor, it has been found that a Perfect-Slip Model (PSM) taking into account the slipping between tapes in a stacked-tape cable during bending gives much better estimation of the bending performance compared to a No-Slip Model (NSM). In the PSM case the tapes can slip so that the internal longitudinal axial strain can be released. The longitudinal strains of compression and tension regions along the tape are balanced in one twist-pitch and cancel out evenly in a long cable. Therefore, in a cable the strains due to bending can be minimized. This is an important advantage of a TSTC conductor. The effect of the cable diameter size on the bending strain is also expected to be minor, and all tapes composing a TSTC conductor have the same strain response under bending, therefore the cable critical current can be characterized from a single tape behaviour.

  3. Electrical characterization of S/C conductor for the CMS solenoid

    CERN Document Server

    Fabbricatore, P; Farinon, S; Greco, Michela; Kircher, F; Musenich, R

    2005-01-01

    The Compact Muon Solenoid (CMS) is one of the general-purpose detectors to be provided for the LHC project at CERN. The design field of the CMS superconducting magnet is 4 T, the magnetic length is 12.5 m and the free bore is 6 m. The coil is wound from 20 high purity aluminum-stabilized NbTi conductors with a total length of 45 km. The main peculiarity of the CMS magnet among other existing thin detector solenoids is its sandwich-type aluminum-stabilized superconductor. This special feature was chosen in order to have a mechanically self-supporting winding structure. We measured the critical current of all the 21 finished conductors in fields up to 6 T using the Ma.Ri.S.A. test facility at INFN-Genova. We compare these results with the critical current of single strands measured by CEA- Saclay, extracted from the conductor after the co-extrusion. A comparison among the measurements provides information about the possible critical current degradation and assures an accurate quality control of the conductor pr...

  4. Neutron Scattering Studies of the Ionic Conductor LiI D2O

    DEFF Research Database (Denmark)

    Andersen, N. H.; Kjems, Jørgen; Poulsen, Finn Willy

    1982-01-01

    The structural properties of the ionic conductor LiID2O have been studied by neutron scattering. The cubic room temperature α-phase, Pm3m, is disordered both with respect to the occupation of the Li+-positions and to the orientations of the water molecules. A first order phase transition from the...

  5. Electrochemical H-D isotope effect at metal-perovskite proton conductor interfaces

    DEFF Research Database (Denmark)

    Kek, D.; Bonanos, N.

    The H-D isotope effect on the electrode kinetics of a metal-proton conductor interface has been investigated. The current-voltage behaviour depends on the nature of the electrode (Ni, Ag), the atmosphere (H(2), D(2)), the partial pressures of the gases, and the temperature. The isotope effect was...

  6. Active Power Flow Optimization of Industrial Power Supply with Regard to the Transmission Line Conductor Heating

    Directory of Open Access Journals (Sweden)

    Leyzgold D.Yu.

    2015-04-01

    Full Text Available This article studies the problem of the transmission line conductor heating effect on the active power flows optimization in the local segment of industrial power supply. The purpose is to determine the optimal generation rating of the distributed power sources, in which the power flow values will correspond to the minimum active power losses in the power supply. The timeliness is the need to define the most appropriate rated power values of distributed sources which will be connected to current industrial power supply. Basing on the model of active power flow optimization, authors formulate the description of the nonlinear transportation problem considering the active power losses depending on the transmission line conductor heating. Authors proposed a new approach to the heating model parameters definition based on allowable current loads and nominal parameters of conductors as part of the optimization problem. Analysis of study results showed that, despite the relatively small active power losses reduction to the tune 0,45% due to accounting of the conductors heating effect for the present configuration of power supply, there are significant fluctuations in the required generation rating in nodes of the network to 9,32% within seasonal changes in the outer air temperature. This fact should be taken into account when selecting the optimum power of distributed generation systems, as exemplified by an arbitrary network configuration.

  7. Electrodynamics of Moving Conductors in Magnetic Fields: Off the Beaten Track with Paul Lorrain

    Science.gov (United States)

    Bringuier, E.

    2012-01-01

    The paper is about the appearance of space charge in an ohmic conductor moving in a magnetic field, as pointed out in this journal by Lorrain (1990 "Eur. J. Phys." 11 94-8) and earlier by van Bladel (1973 "Proc. IEEE" 61 260-8). The phenomenon is reinvestigated here in the light of energy balance considerations, in the particular case of a…

  8. Uncover the electroluminescence in wide band gap polymers

    Science.gov (United States)

    Qiao, B.; Teyssedre, G.; Laurent, C.

    2015-10-01

    Due to the rapidly increasing demand of electric power, insulating materials used in electrical components are pushed up to their limits, where their electronic properties are of fundamental importance. Electroluminescence provides an elegant way to investigate electronic properties, high field effects and electrical ageing of polymers although the emission spectrum is still poorly understood. Unlike in organic semi-conductors, electroluminescence spectra of large band gap polymers exhibit specific spectral features that cannot be interpreted on the basis of the photo-physical properties of the material. By irradiating polypropylene thin films with electrons up to a few keV and by analyzing the emitted light, we were able to isolate the elementary components of the emission and to reconstruct the electroluminescence spectrum. For the first time, a comprehensive study of electroluminescence in polymers is provided and the underlying mechanisms of the emission are discussed. The results herein provide an univocal demonstration that the electroluminescence from wide band gap polymers results in part from chemical reactions, opening the way to the diagnosis and prognosis of polymeric materials under electrical stress.

  9. AC loss reduction of TFA-MOD coated conductors in long length by laser scribing technique

    Science.gov (United States)

    Katayama, K.; Hirano, H.; Machi, T.; Takagi, Y.; Takahashi, Y.; Izumi, T.

    TFA-MOD process is expected to be promising for future applications since it can produce high performance YBCO coated conductors with low cost. Applying YBCO coated conductors to the power electric devices such as transformer, cable, motors, reduction of AC loss for long wire is necessary. Multifilamentation, which is one of the effective approaches for AC loss reduction, has been developed by the scribing process. YBCO coated conductors produced by our standard TFA-MOD process delaminated into two parts by the laser scribing. The delamination was clarified to occur within the superconducting layer caused by the defects such as pores in the superconducting layer. In order to reduce the defects in the superconducting layer, we modify the heat treatment profile performed on the decomposed precursor films by applying the interim annealing(550-600°C) before crystallization heat treatment(740-770°C). The interim annealed samples had much less and smaller pores than the standard processed ones. The peel strength measured by transverse tensile test was as high as the PLD derived coated conductors which was successfully scribed into five filaments resulting in 1/5 AC loss. A 50m long YBCO coated conductor with the characteristics of 398A/cmwidth was obtained and cut into 5 mm width, followed by the laser scribing process into five filaments. The multifilamentation process was successfully performed without delamination throughout the wire. The hysteresis loss was down to 1/N (N: number of filaments), as we aimed. The IC properties of the filaments were 29±4A, indicating the wire was uniformly fabricated.

  10. The Conductor As Visual Guide: Gesture and Perception of Musical Content

    Science.gov (United States)

    Kumar, Anita B.; Morrison, Steven J.

    2016-01-01

    Ensemble conductors are often described as embodying the music. Researchers have determined that expressive gestures affect viewers’ perceptions of conducted ensemble performances. This effect may be due, in part, to conductor gesture delineating and amplifying specific expressive aspects of music performances. The purpose of the present study was to determine if conductor gesture affected observers’ focus of attention to contrasting aspects of ensemble performances. Audio recordings of two different music excerpts featuring two-part counterpoint (an ostinato paired with a lyric melody, and long chord tones paired with rhythmic interjections) were paired with video of two conductors. Each conductor used gesture appropriate to one or the other musical element (e.g., connected and flowing or detached and crisp) for a total of sixteen videos. Musician participants evaluated 8 of the excerpts for Articulation, Rhythm, Style, and Phrasing using four 10-point differential scales anchored by descriptive terms (e.g., disconnected to connected, and angular to flowing.) Results indicated a relationship between gesture and listeners’ evaluations of musical content. Listeners appear to be sensitive to the manner in which a conductor’s gesture delineates musical lines, particularly as an indication of overall articulation and style. This effect was observed for the lyric melody and ostinato excerpt, but not for the chords and interjections excerpt. Therefore, this effect appears to be mitigated by the congruence of gesture to preconceptions of the importance of melodic over rhythmic material, of certain instrument timbres over others, and of length between onsets of active material. These results add to a body of literature that supports the importance of the visual component in the multimodal experience of music performance. PMID:27458425

  11. Effect of current imbalance on stability of a cable-in-conduit conductor consisting of chrome-plated strands

    International Nuclear Information System (INIS)

    The effect of an unbalanced current distribution in a conductor consisting of chrome plated strands on stability was investigated using a cable-in-conduit conductor (CICC) consisting of 27 NbTi chrome-plated strands. In addition, the quench behavior when a non-uniform current distribution was produced in the conductor was studied from the experimental results. Moreover, impedance of the chrome-plated strands was measured using the sample conductor. The results show that the stability is determined by the largest strand current when it is sufficiently large otherwise by the transport current when it is not high enough. It was found that it took a long time to make the conductor quench from the onset of the normal transition of the strand carrying the large current. This is explained by the good diffusivity of the coolant temperature in the conductor's cross section. Since the ramp-rate limitation cannot probably take place if the coolant temperature is diffused well in the conductor's cross section, it is expected the ramp-rate limitation can be prevented using this effect. It is also shown that the chrome-plated strands come into contact with one another with uniform transverse conductance on the order of 103 S/m. (author)

  12. Energy band modulation of graphane by hydrogen-vacancy chains: A first-principles study

    Directory of Open Access Journals (Sweden)

    Bi-Ru Wu

    2014-08-01

    Full Text Available We investigated a variety of configurations of hydrogen-vacancy chains in graphane by first-principles density functional calculation. We found that graphane with two zigzag H-vacancy chains segregated by one or more H chain is generally a nonmagnetic conductor or has a negligible band gap. However, the same structure is turned into a semiconductor and generates a magnetic moment if either one or both of the vacancy chains are blocked by isolated H atoms. If H-vacancy chains are continuously distributed, the structure is similar to a zigzag graphene nanoribbon embedded in graphane. It was also found that the embedded zigzag graphene nanoribbon is antiferromagnetic, and isolated H atoms left in the 2-chain nanoribbon can tune the band gap and generate net magnetic moments. Similar effects are also obtained if bare carbon atoms are present outside the nanoribbon. These results are useful for designing graphene-based nanoelectronic circuits.

  13. Energy band modulation of graphane by hydrogen-vacancy chains: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Bi-Ru [Department of Natural science, Center for General Education, Chang Gung University, Kueishan 333, Taiwan, ROC (China); Yang, Chih-Kai, E-mail: ckyang@nccu.edu.tw [Graduate Institute of Applied Physics, National Chengchi University, Taipei 11605, Taiwan, ROC (China)

    2014-08-15

    We investigated a variety of configurations of hydrogen-vacancy chains in graphane by first-principles density functional calculation. We found that graphane with two zigzag H-vacancy chains segregated by one or more H chain is generally a nonmagnetic conductor or has a negligible band gap. However, the same structure is turned into a semiconductor and generates a magnetic moment if either one or both of the vacancy chains are blocked by isolated H atoms. If H-vacancy chains are continuously distributed, the structure is similar to a zigzag graphene nanoribbon embedded in graphane. It was also found that the embedded zigzag graphene nanoribbon is antiferromagnetic, and isolated H atoms left in the 2-chain nanoribbon can tune the band gap and generate net magnetic moments. Similar effects are also obtained if bare carbon atoms are present outside the nanoribbon. These results are useful for designing graphene-based nanoelectronic circuits.

  14. Radiation Characteristic Improvement of X-Band Slot Antenna Using New Multiband Frequency-Selective Surface

    Directory of Open Access Journals (Sweden)

    Elham Moharamzadeh

    2014-01-01

    Full Text Available A new configuration of frequency-selective surfaces (FSSs is designed and presented with multiresonance characteristics which covers all of the frequency domain of X-band from 8 to 12 GHz. The proposed FSS comprises three conductor-based split ring resonators, connected together. In this design, two unit cells of the FSS with different lengths are employed side by side to design the FSS. The FSS is used to enhance the gain of the new designed triangle slot antenna at X-band. The proposed FSS is analyzed by using reflected-wave unit-cell box method. The single, double, and array of the FSS cells are studied. Next, the designed FSS along with the antenna is analyzed. The measurement and simulated results of the impedance and radiation characteristics, especially the increment of the gain, are presented.

  15. Conductors with small Fermi energies and small gap energies

    International Nuclear Information System (INIS)

    If the Fermi energy is of the order of meV's, the usual treatment of the density of free electrons is not valid, but use can be made of an averaged density of states that depends weakly on temperature, so that the temperature variation of the conductivity can be expressed by the equation: σ congruent CT(1-s) 1n{[(exp(βEf) + 1)/2][exp(-β(Eg - Ef)) + 1)]} in which Ef is the Fermi energy, Eg is the top of the energy gap for thermal activation, s is the exponent of the temperature-dependent scattering. This equation serves to define a class of solids consisting of a microcomposite with a narrow conduction band for which Ef of the order of ceV's or less and a thermal activated conduction for which Eg is of the order of ceV's. It describes quantitatively the conductivity, σ(T;Δ, for YBa2Cu3O7-Δ and σ(T;p) as the hydrostatic pressure p is varied for κ-(BEDT-TTF)2CuN(CN)2Br

  16. Flat Bands Under Correlated Perturbations

    OpenAIRE

    Bodyfelt, Joshua D.; Leykam, Daniel; Danieli, Carlo; Yu, Xiaoquan; Flach, Sergej

    2014-01-01

    Flat band networks are characterized by coexistence of dispersive and flat bands. Flat bands (FB) are generated by compact localized eigenstates (CLS) with local network symmetries, based on destructive interference. Correlated disorder and quasiperiodic potentials hybridize CLS without additional renormalization, yet with surprising consequencies: (i) states are expelled from the FB energy $E_{FB}$, (ii) the localization length of eigenstates vanishes as $\\xi \\sim 1 / \\ln (E- E_{FB})$, (iii)...

  17. Cluster banding heat source model

    Institute of Scientific and Technical Information of China (English)

    Zhang Liguo; Ji Shude; Yang Jianguo; Fang Hongyuan; Li Yafan

    2006-01-01

    Concept of cluster banding heat source model is put forward for the problem of overmany increment steps in the process of numerical simulation of large welding structures, and expression of cluster banding heat source model is deduced based on energy conservation law.Because the expression of cluster banding heat source model deduced is suitable for random weld width, quantitative analysis of welding stress field for large welding structures which have regular welds can be made quickly.

  18. Development of Wide Band Feeds

    Science.gov (United States)

    Ujihara, H.; Ichikawa, R.

    2012-12-01

    Wide Band feeds are being developed at NICT, NAOJ, and some universities in Japan for VLBI2010, SKA, and MARBLE. SKA, the Square Kilometre Array, will comprise thousands of radio telescopes with square kilometer aperture size for radio astronomy. MARBLE consists of small portable VLBI stations developed at NICT and GSI in Japan. They all need wide band feeds with a greater than 1:10 frequency ratio. Thus we have been studying wide band feeds with dual linear polarization for these applications.

  19. An innovative contactless method for detecting defects in electrical conductors by measuring a change in electromagnetic torque

    International Nuclear Information System (INIS)

    This paper presents a new non-destructive testing (NDT) method for the detection of defects in electrical conductors. The method distinguishes defect-embedded and defect-free conductors via the variation of angular velocity and electromagnetic torque on a single cylindrical permanent magnet. To demonstrate the feasibility of this method, numerical and experimental investigations have been performed. Quantitative relations between the electromagnetic torque, angular velocity and defect sizes have been obtained and can be considered as calibration functions for this new technique. This study demonstrates that this approach might offer an effective method of detecting the presence of defects in electrical conductors. (paper)

  20. Garage Band or GarageBand[R]? Remixing Musical Futures

    Science.gov (United States)

    Vakeva, Lauri

    2010-01-01

    In this paper, I suggest that it is perhaps time to consider the pedagogy of popular music in more extensive terms than conventional rock band practices have to offer. One direction in which this might lead is the expansion of the informal pedagogy based on a "garage band" model to encompass various modes of digital artistry wherever this artistry…

  1. Simultaneous confidence bands in linear regression analysis

    OpenAIRE

    Ah-Kine, Pascal Soon Shien

    2010-01-01

    A simultaneous confidence band provides useful information on the plausible range of an unknown regression model. For a simple linear regression model, the most frequently quoted bands in the statistical literature include the two-segment band, the three-segment band and the hyperbolic band, and for a multiple linear regression model, the most com- mon bands in the statistical literature include the hyperbolic band and the constant width band. The optimality criteria for confid...

  2. HTS current lead units prepared by the TFA-MOD processed YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Shiohara, K.; Sakai, S.; Ishii, Y. [Tokai University, 1117 Kita-Kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Yamada, Y., E-mail: yyamaday@keyaki.cc.u-tokai.ac.j [Tokai University, 1117 Kita-Kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Tachikawa, K. [Tokai University, 1117 Kita-Kaname, Hiratsuka, Kanagawa 259-1292 (Japan); Koizumi, T.; Aoki, Y.; Hasegawa, T. [SWCC Showa Cable System Co., LTD, 4-1-1 Minami-Hashimoto, Sagamihara, Kanagawa 229-1133 (Japan); Tamura, H.; Mito, T. [NIFS National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan)

    2010-11-01

    Two superconducting current lead units have been prepared using ten coated conductors of the Tri-Fluoro-Acetate - Metal Organic Deposition (TFA-MOD) processed Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-{delta}}(YBCO) coated conductors with critical current (I{sub c}) of about 170 A at 77 K in self-field. The coated conductors are 5 mm in width, 190 mm in length and about 120 {mu}m in overall thickness. The 1.5 {mu}m thick superconducting YBCO layer was synthesized through the TFA-MOD process on Hastelloy{sup TM} C-276 substrate tape with two buffer oxide layers of Gd{sub 2}Zr{sub 2}O{sub 7} and CeO{sub 2}. The five YBCO coated conductors are attached on a 1 mm thick Glass Fiber Reinforced Plastics (GFRP) board and soldered to Cu caps at the both ends. We prepared two 500 A-class current lead units. The DC transport current of 800 A was stably applied at 77 K without any voltage generation in all coated conductors. The voltage between both Cu caps linearly increased with increasing the applied current, and was about 350 {mu}V at 500 A in both current lead units. According to the estimated values of the heat leakage from 77 K to 4.2 K, the heat leakage for the current lead unit was 46.5 mW. We successfully attained reduction of the heat leakage because of improvement of the transport current performance (I{sub c}), a thinner Ag layer of YBCO coated conductor and usage of the GFRP board for reinforcement instead of a stainless steel board used in the previous study. The DC transport current of 1400 A was stably applied when the two current lead units were joined in parallel. The sum of the heat leakages from 77 K to 4.2 K for the combined the current lead units was 93 mW. In comparison with the conventional Cu current leads by gas-cooling, it could be noted that the heat leakage of the current lead is about one order of magnitude smaller than that of the Cu current lead.

  3. HTS current lead units prepared by the TFA-MOD processed YBCO coated conductors

    International Nuclear Information System (INIS)

    Two superconducting current lead units have been prepared using ten coated conductors of the Tri-Fluoro-Acetate - Metal Organic Deposition (TFA-MOD) processed Y1Ba2Cu3O7-δ (YBCO) coated conductors with critical current (Ic) of about 170 A at 77 K in self-field. The coated conductors are 5 mm in width, 190 mm in length and about 120 μm in overall thickness. The 1.5 μm thick superconducting YBCO layer was synthesized through the TFA-MOD process on HastelloyTM C-276 substrate tape with two buffer oxide layers of Gd2Zr2O7 and CeO2. The five YBCO coated conductors are attached on a 1 mm thick Glass Fiber Reinforced Plastics (GFRP) board and soldered to Cu caps at the both ends. We prepared two 500 A-class current lead units. The DC transport current of 800 A was stably applied at 77 K without any voltage generation in all coated conductors. The voltage between both Cu caps linearly increased with increasing the applied current, and was about 350 μV at 500 A in both current lead units. According to the estimated values of the heat leakage from 77 K to 4.2 K, the heat leakage for the current lead unit was 46.5 mW. We successfully attained reduction of the heat leakage because of improvement of the transport current performance (Ic), a thinner Ag layer of YBCO coated conductor and usage of the GFRP board for reinforcement instead of a stainless steel board used in the previous study. The DC transport current of 1400 A was stably applied when the two current lead units were joined in parallel. The sum of the heat leakages from 77 K to 4.2 K for the combined the current lead units was 93 mW. In comparison with the conventional Cu current leads by gas-cooling, it could be noted that the heat leakage of the current lead is about one order of magnitude smaller than that of the Cu current lead.

  4. The Moral Ends of Band

    Science.gov (United States)

    Allsup, Randall Everett

    2012-01-01

    This article provides a theoretical framework through which to reimagine and revitalize contemporary music education practices, using the large ensemble paradigm called "band" as the primary unit of analysis. Literature suggests that band places too much emphasis on teacher control and external measures of validation. Critics propose replacing…

  5. Chemical behaviour of trivalent and pentavalent americium in saline NaCl-solutions. Studies of transferability of laboratory data to natural conditions. Interim report. Reported period: 1.2.1993-31.12.1993; Chemisches Verhalten von drei- und fuenfwertigem Americium in Salinen NaCl-Loesungen. Untersuchung der Uebertragbarkeit von Labordaten auf natuerliche Verhaeltnisse. Zwischenbericht. Berichtszeitraum 1.2.1993-31.12.1993

    Energy Technology Data Exchange (ETDEWEB)

    Runde, W.; Kim, J.I.

    1994-09-15

    In order to clarify the chemical behaviour of Americium in saline aqueous systems relevant for final storage this study deals with the chemical reactions of trivalent and pentavalent Americium in NaCl-solutions under the influence of radiolysis from its own alpha radiation. The focus of the study was on investigating the geologically relevant reactions, such as hydrolysis or carbonate- and chloride complexing in solid-liquid equilibriums. Comprehensive measurements on solubility and spectroscopic studies in NaCl-solutions were carried out in a CO{sub 2}-free atmosphere and 10{sup -2} atm CO{sub 2} partial pressure. Identification and characterisation of the AM (III) and AM(V) solid phases were supplemented by structural research with the chemically analogue EU (III) and Np(V) compounds. The alpha-radiation induced radiolysis in saline NaCl solutions and the redox behaviour of Americium which was influenced thereby were spectroscopically quantified. (orig.) [Deutsch] Zur Klaerung des chemischen Verhaltens von Americium in endlagerrelevanten salinen aquatischen Systemen befasst sich die vorliegende Arbeit mit den chemischen Reaktionen des drei- und fuenfwertigen Americiums in NaCl-Loesungen unter dem Einfluss der Radiolyse durch die eigene {alpha}-Strahlung. Der Schwerpunkt dieser Arbeit lag auf der Untersuchung der geologisch relevanten Reaktionen, wie Hydrolyse sowie Carbonat- und Chloridkomplexierung in fest-fluessig Gleichgewichtssystemen. Hierzu wurden umfassende Loeslichkeitsmessungen und spektroskopische Untersuchungen in NaCl-Loesungen, sowohl unter CO{sub 2}-freier Atmosphaere als auch unter 10{sup -2} atm CO{sub 2}-Partialdruck, durchgefuehrt. Die Identifizierung und Charakterisierung der Am(III)- und Am(V)-Festphasen wurde ergaenzt durch strukturelle Untersuchungen mit den chemisch analogen Eu(III)- und Np(V)-Verbindungen. Die von der {alpha}-Strahlung induzierte Radiolyse in salinen NaCl-Loesungen und das dadurch beeinflusste Redoxverhalten von Americium

  6. Influence of magnetization on field quality in cosine-theta and block design dipole magnets wound with coated conductors

    Science.gov (United States)

    Sogabe, Yusuke; Sakashita, Masaki; Nakamura, Taketsune; Ogitsu, Toru; Amemiya, Naoyuki

    2016-04-01

    We carried out electromagnetic field analyses on the cross sections of two dipole magnets wound with coated conductors. One was a cosine-theta magnet, and the other was a block design magnet. The electric field-current density characteristics of the coated conductors were formulated using a percolation depinning model based on the measured voltage-current characteristics. We calculated the temporal evolutions of the current-density distributions in all the turns of each magnet and used these evolutions to calculate the multipole components of the magnetic field. We compared the two magnets, which differed in coated-conductor orientations, regarding the influence of coated-conductor magnetization on the field qualities.

  7. Effects of conductor anisotropy on the design of Bi-Sr-Ca-Cu-O sections of 25 T solenoids

    International Nuclear Information System (INIS)

    The development of a 25 T superconducting magnet is usually envisioned with the use of an innermost coil wound with high-temperature superconductor (HTS) material. At present, Bi2Sr2CaCu2Ox and Bi2Sr2Ca2Cu3Ox (BSCCO) conductors are the only candidate conductors available with sufficient length and current carrying capability. Unlike NbTi and Nb3Sn conductors, the BSCCO crystal structure and thus properties are strongly anisotropic. In conductor form, various degrees of anisotropy occur. It is often assumed that this anisotropy simply implies that radial field components must be minimized. We show that this assumption can be misleading. Using the average grain colony misalignment angle to parameterize the anisotropy, three regimes are distinguished in the relationship between average grain colony misalignment and critical current limiting field components. The implications of these separate regimes on the design process for 25 T superconducting magnet design are discussed

  8. The Study of Electromagnetic Scattering by a Non-perfectly Conductor in Chiral Media by Potential Theory

    Institute of Scientific and Technical Information of China (English)

    GAO TIAN-LING; LIU QIANG; Ma Fu-ming

    2012-01-01

    This paper is concerned with the electromagnetic scattering by a nonperfectly conductor obstacle in chiral environment.A two-dimensional mathematical model is established.The existence and uniqueness of the problem are discussed by potential theory.

  9. Calculation of the ac to dc resistance ratio of conductive nonmagnetic straight conductors by applying FEM simulations

    Science.gov (United States)

    Riba, Jordi-Roger

    2015-09-01

    This paper analyzes the skin and proximity effects in different conductive nonmagnetic straight conductor configurations subjected to applied alternating currents and voltages. These effects have important consequences, including a rise of the ac resistance, which in turn increases power loss, thus limiting the rating for the conductor. Alternating current (ac) resistance is important in power conductors and bus bars for line frequency applications, as well as in smaller conductors for high frequency applications. Despite the importance of this topic, it is not usually analyzed in detail in undergraduate and even in graduate studies. To address this, this paper compares the results provided by available exact formulas for simple geometries with those obtained by means of two-dimensional finite element method (FEM) simulations and experimental results. The paper also shows that FEM results are very accurate and more general than those provided by the formulas, since FEM models can be applied in a wide range of electrical frequencies and configurations.

  10. Development of a high Jc bronze route Nb3Sn conductor using Nb-Ta composite filaments

    International Nuclear Information System (INIS)

    For superconducting magnets generating fields above 10 tesla, multifilamentary Nb3Sn is the conductor of choice. There are two widely used methods of manufacturing these conductors, namely the internal Sn route and bronze process. Bronze route conductors can yield long piece lengths with consistent performances due to the mechanical compatibilities of the components compared to internal Sn conductors. Internal Sn designs require a soft low melting point Sn and is more difficult to be co-processed with the significantly harder Nb filaments. This paper summarizes the development of a bronze route Nb3Sn wire with high Jc using Nb-Ta composite filaments for use in advanced projects such as the International Thermonuclear Experimental Reactor (ITER)

  11. Bend strain tolerance of YBa2Cu3O7-x-coated conductors fabricated by inclined substrate deposition

    International Nuclear Information System (INIS)

    The effect of tensile bend strain on the critical current of YBa2Cu3O7-x (YBCO)-coated conductors was evaluated as a function of YBCO film thickness. The YBCO-coated conductors were fabricated on Hastelloy C276 metal substrates templated with MgO by inclined substrate deposition. It was observed that a conductor with 0.2 μm thick YBCO retained 90% of the unstrained critical current until a strain of ∼0.4%, whereas for a conductor with 0.5 μm thick YBCO film the critical strain value was ∼0.2%. At strains higher than the critical strain, the critical current dropped precipitously. The inverse dependence of bend strain tolerance on the YBCO film thickness is in reasonable agreement with analytical prediction. This inverse dependence was used to approximate the fracture toughness of the YBCO film, which was found to be in general agreement with the literature

  12. Bend strain tolerance of YBa2Cu3O7-x-coated conductors fabricated by inclined substrate deposition

    Science.gov (United States)

    Shankar, P. S.; Singh, J. P.; Ma, B.; Koritala, R.; Fisher, B. L.; Balachandran, U.

    2006-09-01

    The effect of tensile bend strain on the critical current of YBa2Cu3O7-x (YBCO)-coated conductors was evaluated as a function of YBCO film thickness. The YBCO-coated conductors were fabricated on Hastelloy C276 metal substrates templated with MgO by inclined substrate deposition. It was observed that a conductor with 0.2 µm thick YBCO retained 90% of the unstrained critical current until a strain of ap0.4%, whereas for a conductor with 0.5 µm thick YBCO film the critical strain value was ap0.2%. At strains higher than the critical strain, the critical current dropped precipitously. The inverse dependence of bend strain tolerance on the YBCO film thickness is in reasonable agreement with analytical prediction. This inverse dependence was used to approximate the fracture toughness of the YBCO film, which was found to be in general agreement with the literature.

  13. Canonical Statistical Model for Maximum Expected Immission of Wire Conductor in an Aperture Enclosure

    Science.gov (United States)

    Bremner, Paul G.; Vazquez, Gabriel; Christiano, Daniel J.; Trout, Dawn H.

    2016-01-01

    Prediction of the maximum expected electromagnetic pick-up of conductors inside a realistic shielding enclosure is an important canonical problem for system-level EMC design of space craft, launch vehicles, aircraft and automobiles. This paper introduces a simple statistical power balance model for prediction of the maximum expected current in a wire conductor inside an aperture enclosure. It calculates both the statistical mean and variance of the immission from the physical design parameters of the problem. Familiar probability density functions can then be used to predict the maximum expected immission for deign purposes. The statistical power balance model requires minimal EMC design information and solves orders of magnitude faster than existing numerical models, making it ultimately viable for scaled-up, full system-level modeling. Both experimental test results and full wave simulation results are used to validate the foundational model.

  14. Thermal de-icing of HV conductors by using an external DC source

    Energy Technology Data Exchange (ETDEWEB)

    Breault, S.; Prud' homme, P. [Hydro-Quebec, PQ (Canada). TransEnergie Div.

    2002-07-01

    The Research Institute of Hydro-Quebec is conducting 2 test programs in climatic chambers. It is also compiling a database for conductors, ground wires and optical power ground wires (OPGW). An in-house computer program has also been developed to evaluate de-icing using the Joule effect. Maps illustrating the power transmission network for the entire province were presented. It was shown that de-icing requires 1800 A per every 735 kV conductor. This upper limit is fixed by the thermal rating of the line. The longest line to be de-iced in Quebec is about 250 km long. This would require 850 kV and 6000 MVA of power. The basic de-icing configuration at 315 kV was also illustrated, along with a simulation of the impact of de-icing on ice loading of power lines.

  15. Electrodynamics of moving conductors in magnetic fields: off the beaten track with Paul Lorrain

    Science.gov (United States)

    Bringuier, E.

    2012-01-01

    The paper is about the appearance of space charge in an ohmic conductor moving in a magnetic field, as pointed out in this journal by Lorrain (1990 Eur. J. Phys. 11 94-8) and earlier by van Bladel (1973 Proc. IEEE 61 260-8). The phenomenon is reinvestigated here in the light of energy balance considerations, in the particular case of a cylinder rotating in a parallel uniform magnetic field. Part of the kinetic energy of the rotating body is lost in the Joule effect of the currents building up the space charge, but the greater part is converted to the electrostatic energy of the space-charge distribution. The findings of the paper are consistent with the usual account of the electrodynamics of moving media where the existence of space charge in good conductors is not recognized. The material of the paper can be taught at the end of second-year university lectures on electrodynamics.

  16. Low AC Loss YBCO Coated Conductor Geometry by Direct Inkjet Printing

    Energy Technology Data Exchange (ETDEWEB)

    Rupich, Martin, Dr. [American Superconductor Corporation; Duckworth, Robert, Dr. [Oak Ridge National Laboratory

    2009-10-01

    The second generation (2G) high temperature superconductors (HTS) wire offers potential benefits for many electric power applications, including ones requiring filamentized conductors with low ac loss, such as transformers and fault current limiters. However, the use of 2G wire in these applications requires the development of both novel multi-filamentary conductor designs with lower ac losses and the development of advanced manufacturing technologies that enable the low-cost manufacturing of these filamentized architectures. This Phase I SBIR project focused on testing inkjet printing as a potential low-cost, roll-to-roll manufacturing technique to fabricate potential low ac loss filamentized architectures directly on the 2G template strips.

  17. Conductor stress analysis for the mirror fusion test facility (MFTF) magnet system

    International Nuclear Information System (INIS)

    This report describes the analysis performed to establish the sensitivity of winding gaps on conductor hoop stress. Since this task was a follow-on to the program that confirmed the structural integrity of the MFTF magnet case, jacket, and shield system, every effort was made to utilize analysis methods and tools developed during that program. The large, 5000 degree of freedom GDSAP model developed during that program which was used extensively throughout this analysis task is presented. This model accurately represents the case and jacket structure and simulates the conductor pack stiffness with an array of interconnected rod elements. All results contained herein are based on linear-elastic, small deflection theory. To enable us to use this analysis tool, homogenization techniques were utilized to idealize the non-linear gap problem into a linear problem compatible with our existing analysis techniques. Details of the homogenization are presented

  18. Effect of wire configuration and point defects on the conductance of gold nano-conductors

    International Nuclear Information System (INIS)

    Gold nanowire (NW) chains are considered a good candidate for nano-electronics devices because they exhibit remarkable structural and electrical properties. One promising nano-conductor candidate is called ‘Hexa1’. It has a two-dimensional, one atom thick structure and was found to spontaneously form during simulations of gold NWs elongations. It is stable and a good conductor when adsorbed on a suitable substrate. In this study, we deepened the investigation of such a NW structure, to explore the effect of the NWs length, point defects and NW junctions on its conductance. We found that the conductance is not affected by the NW length, and that conveniently placed point defects can be used to create resistors. We also found that direction changes in circuits produce conductance bottle necks, therefore decreasing the conductance. However, this decrease can be easily overcome by adding a few atoms to the NW junction. (paper)

  19. A radiation hard dipole magnet coils using aluminum clad copper conductors

    Energy Technology Data Exchange (ETDEWEB)

    Leonhardt, W.J.

    1989-01-01

    A C-type septum dipole magnet is located 600 mm downstream of the primary target in an external beam line of the AGS. Conventional use of fiber glass/epoxy electrical insulation for the magnet coils results in their failure after a relatively short running period, therefore a radiation hard insulation system is required. This is accomplished by replacing the existing copper conductor with a copper conductor having a thin aluminum skin which is anodized to provide the electrical insulation. Since the copper supports a current density of 59 A/mm/sup 2/, no reduction in cross sectional area can be tolerated. Design considerations, manufacturing techniques, and operating experience of a prototype dipole is presented. 3 refs., 4 figs.

  20. Magnetization Losses of Roebel Cable Samples with 2G YBCO Coated Conductor Strands

    CERN Document Server

    Yang, Y.; Falorio, I.; Young, E.A.; Kario, A.; Goldacker, W.; Dhallé, M. M. J.; van Nugteren, J.; Kirby, G.; Bottura, L.; Ballarino, A.; 10.1109/TASC.2016.2525926

    2016-01-01

    Roebel cable with 2G YBCO strands is one of the promising HTS solutions of fully transposed high current conductors for high field accelerator magnets. Following the considerable research effort on the manufacturing of Roebel cables in recent years, sample conductors are now available in useful lengths with reproducible performances to allow detailed characterizations beyond the standard critical current measurements. The ac loss and strands coupling are of significant interest for the field quality of the accelerator magnets. We report a set of systematic ac loss measurements on two different Roebel cable samples prepared for the EuCARD2 collaboration. The measurements were performed over a wide range of temperature between 5 K and 90 K and the results were analyzed in the context of strands architecture and coupling. The results show that the transposed bundles are partially decoupled and the strands in transposition sections behave as an isolated single tape if the strands are insulated.

  1. Construction and test of a non-insulated insert coil using coated conductor tape

    International Nuclear Information System (INIS)

    A small coated conductor coil (central field 1 T at 200 A) was constructed and tested in order to evaluate the benefit and the possible disadvantages of non insulated, double pancake construction, in particular regarding quench protection. The insert coil consists of three double pancakes without turn to turn insulation, and it was impregnated with beeswax. The coil was equipped with voltage taps on each pancake, thermocouples and a quench heater. Quench tests were carried out because quench protection is one of the main issues in developing coil technology for coated conductors. Quenches were induced either by a heater or by exceeding the coil critical current; in all cases the quench protection system was able to detect the quench.

  2. On the stability limits of the Pinch-conductor current ratio in Extrap

    International Nuclear Information System (INIS)

    A first attempt is made to take the special stability features of the Extrap confinement scheme into account, thereby including kinetic large Larmor radius (LLR) effects. This approach predicts Extrap to be unstable outside a domain defined by a lower and an upper ratio a-/ax is related to the ratio Jp/Jv between the pinch current Jp and the conductor current Jv. Stability within the predicted domain seems to agree with so far performed linear and toroidal experiments, and can explain the observed increase in Jp/Jv and in the plasma temperature, in terms of an increased ratio a-/ax. According to present analysis, an optimum value of the conductor current Jv should further exist with respect to pinch equilibrium and stability, as given by the condition a- approx = ax. (author)

  3. Quasi In Situ Polymerization To Fabricate Copper Nanowire-Based Stretchable Conductor and Its Applications.

    Science.gov (United States)

    Wang, Tao; Wang, Ranran; Cheng, Yin; Sun, Jing

    2016-04-13

    Stretchable electronics have progressed greatly and have found their way into various applications, thus resulting in a growing demand for high-quality stretchable conductors. Poly(dimethylsiloxane) (PDMS) is the mostly frequently exploited elastomeric substrate for the construction of a stretchable and conductive platform because of its valuable features, such as superb stretch ability, high transparency, and reliable biocompatibility. However, the weak adhesion between the PDMS substrate and the conductive components has always been an intractable issue which undermines the good and stable performance of the resultant devices. We proposed a quasi in situ polymerization method to effectively build a tight and stable attachment between copper nanowire (Cu NW) and the PDMS substrate. The Cu NWs/PDMS conductors show excellent conductivity and antioxidation stability (R/R0 capacitive strain sensor was fabricated using the Cu NWs/PDMS as electrodes. The sensor possessed a gauge factor of 0.82 and the minimum detection limit of 1% strain. PMID:26895474

  4. Power flux distribution in chiroplasma-filled perfect electromagnetic conductor circular waveguides

    Science.gov (United States)

    Ghaffar, A.; Alkanhal, Majeed A. S.

    2016-03-01

    Theoretical analysis of the electromagnetic wave propagation in circular waveguides with a chiroplasma core coated with a perfect electromagnetic conductor (PEMC) is presented. The presented formulations and analysis are general for any perfect electric, perfect magnetic, or perfect electromagnetic conductor (PEMC) waveguides filled with any general anisotropic/isotropic metamaterial including plasma. The characteristic equation for the modes in this waveguide is obtained, and the behavior of the dispersion curves and the power flux are examined and evaluated numerically. The results demonstrate that the behavior of the power flux transported in the guide, in magnitude and orientation, is highly determined by the chirality parameter and the plasma and cyclotron frequencies. The mode cutoff frequencies are sensitive to the variations in the filling material and chirality parameters and likewise affected by the variations in the PEMC admittance parameter.

  5. YBCO coated conductors on highly textured Pd-buffered Ni-W tape

    International Nuclear Information System (INIS)

    High critical current density YBa2Cu3O7-x (YBCO) coated conductors were obtained on cube textured Ni-W. The use of a Pd transient layer as a first buffer led to a sharp out-of-plane grains alignment of the CeO2/YSZ/CeO2 buffer layer. YBCO films grown on this template exhibit an out-of-plane orientation with a full width at half maximum of about 30, less than 50% of the respective starting Ni-W value. Despite the complete interdiffusion between Ni-W and Pd after the YBCO film deposition, the coated conductors exhibit good film adherence as well as a crack free and smooth surface of the YBCO film. YBCO thin films show critical temperature values above than 88 K and a critical current density of 2.1 MA/cm2 at 77 K and self field

  6. Fabrication and testing of long length high-{Tc} composite conductors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, L.M.

    1997-12-31

    Presently some methods of HTS-conductors processing are under study in the authors laboratory. ``Powder-in-tube`` (PIT), ``Jelly-roll``, electrophorethis are among them. PIT process has developed predominantly both in a view of the achieved J{sub c} values Bi-2223 phase was used as a core material for these tapes. Since the main purpose of the task order was to enhance the development of long length high temperature superconductor tapes, the authors have considered reasonable to lay the perfection idea of the PIT process step by step or tape by tape. To realize it they have assumed, keeping stable the basic scheme of PIT process, to vary some technological parameters which are as follows: (1) type of initial powder; (2) sheath material; (3) tape construction (filaments number, cross section e.a.); and (4) processing regimes. This report covers the fabrication process and characteristics of the produced conductors.

  7. A radiation hard dipole magnet coils using aluminum clad copper conductors

    International Nuclear Information System (INIS)

    A C-type septum dipole magnet is located 600 mm downstream of the primary target in an external beam line of the AGS. Conventional use of fiber glass/epoxy electrical insulation for the magnet coils results in their failure after a relatively short running period, therefore a radiation hard insulation system is required. This is accomplished by replacing the existing copper conductor with a copper conductor having a thin aluminum skin which is anodized to provide the electrical insulation. Since the copper supports a current density of 59 A/mm2, no reduction in cross sectional area can be tolerated. Design considerations, manufacturing techniques, and operating experience of a prototype dipole is presented. 3 refs., 4 figs

  8. Overhead lines: materials. Guard conductors and cables; Lignes aeriennes: materiels. Conducteurs et cables de garde

    Energy Technology Data Exchange (ETDEWEB)

    Chanal, A. [Electricite de France (EDF), 75 - Paris (France). Direction de la Production et du Transport; Leveque, J.P. [Electricite de France (EDF), Reseau de Transport d' Electricite, 75 - Paris (France)

    2003-02-01

    This article presents the characteristics of bare cables for the construction of overhead lines. During the last decades, no important change has been made in the choice of conductive materials. The main materials used are: the high purity cold drawn aluminium in bi-metal aluminium-steel cables, and the 'almelec', an aluminium alloy with a reinforced traction resistance. Recently, new conductors with a higher transport capacity and a better temperature resistance have been developed. Another way of research concerns the combination of conductors and composite materials (carbon fibers) but no satisfactory solutions have been obtained so far. A more important evolution concerns the guard cables for high voltage lines which now include telecommunication circuits (optical fibers) for high flow rate transmission of numerical data. The laying out of such cables has been generalized in France in order to supply the overall territory with equivalent and satisfactory performances. (J.S.)

  9. Artificial perfect electric conductor-perfect magnetic conductor anisotropic metasurface for generating orbital angular momentum of microwave with nearly perfect conversion efficiency

    Science.gov (United States)

    Chen, Menglin L. N.; Jiang, Li Jun; Sha, Wei E. I.

    2016-02-01

    Orbital angular momentum (OAM) is a promising degree of freedom for fundamental studies in electromagnetics and quantum mechanics. The unlimited state space of OAM shows a great potential to enhance channel capacities of classical and quantum communications. By exploring the Pancharatnam-Berry phase concept and engineering anisotropic scatterers in a metasurface with spatially varying orientations, a plane wave with zero OAM can be converted to a vortex beam carrying nonzero OAM. In this paper, we proposed two types of novel perfect electric conductor-perfect magnetic conductor anisotropic metasurfaces. One is composed of azimuthally continuous loops and the other is constructed by azimuthally discontinuous dipole scatterers. Both types of metasurfaces are mounted on a mushroom-type high impedance surface. Compared to previous metasurface designs for generating OAM, the proposed ones achieve nearly perfect conversion efficiency. In view of the eliminated vertical component of electric field, the continuous metasurface shows very smooth phase pattern at the near-field region, which cannot be achieved by convectional metasurfaces composed of discrete scatterers. On the other hand, the metasurface with discrete dipole scatterers shows a great flexibility to generate OAM with arbitrary topological charges. Our work is fundamentally and practically important to high-performance OAM generation.

  10. Effect of the inclusion of small metallic components in a two-dimensional dielectric photonic crystal with large full band gap

    Science.gov (United States)

    Chang, Chien C.; Chi, J. Y.; Chern, R. L.; Chang, C. Chung; Lin, C. H.; Chang, C. O.

    2004-08-01

    In this study, we investigate the effect of metallic inclusion modeled as perfect conductor on a dielectric photonic crystal (silicon/air) with large full band gap. The dielectric crystal consists of a hexagonal array of circular dielectric columns, each connected to its nearest neighbors by slender rectangular rods. It is found that inclusion of small metallic components inside the circular dielectrics sharply “turns off“ the full band gap of the dielectric photonic crystal. By increasing the radius of metallic inclusion above a threshold value, the full band gap (of the metallodielectric photonic crystal) makes its appearance again and continues to grow in size. On the other hand, metallic inclusion in the air region shows an opposite trend that the full band gap is not turned off, and its size diminishes gradually to zero with increasing the radius of inclusion. These peculiar behaviors can be explained on a unified basis by examining different types of boundary conditions for TM and TE modes, and employing variational arguments based on Rayleigh’s quotients. Moreover, the free-electron model for metallic components is also considered for TM modes. At large plasma frequencies, these modes show very close band structures to those described above for the case of perfect conductors.

  11. Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic protontic conductors

    DEFF Research Database (Denmark)

    Li, Qingfeng

    2003-01-01

    contain inorganic protonic conductors including zirconium phosphate (ZrP), (Zr(HPO4)2. nH2O); phosphotungstic acid (PWA), (H3PW12O40. nH2O); and silicotungstic acid (SiWA), (H4SiW12O40 . nH2O). The conductivity of phosphoric acid doped PBI and PBI composite membranes was found to be dependent on the acid...

  12. Test results on prototype 50-kA conductors for tokamak induction heating coils

    International Nuclear Information System (INIS)

    Fabricability of a very large, 50-kA superconducting cable has been demonstrated. Test results of critical current and stability measurements are presented. The design critical current of 55 kA at 7 T was met. The recovery current was degraded as a result of the expectedly poor insulation system. Energy loss measurements on prototype advanced mixed matrix conductors, which will be incorporated into a second prototype cable, are presented

  13. Experimental determination of conduction channels in atomic scale conductors based on shot noise measurements

    OpenAIRE

    Vardimon, Ran; Klionsky, Marina; Tal, Oren

    2013-01-01

    We present an experimental procedure for obtaining the conduction channels of low-dimensional conductors based on shot noise measurements. The transmission coefficient for each channel is determined numerically from the measured conductance and Fano factor. The channel analysis is demonstrated for atomic contacts of Ag, Au, Al and Pt, showing their channel evolution as a function of conductance and mechanical elongation. This approach can be readily applied to map the conduction channels in a...

  14. A novel electronic current-blocked stable mixed ionic conductor for solid oxide fuel cells

    NARCIS (Netherlands)

    Sun, Wenping; Jiang, Yinzhu; Wang, Yanfei; Fang, Shumin; Zhu, Zhiwen; Liu, Wei

    2011-01-01

    A novel ionic conductor, BaCe0.8Sm0.2O3−δ–Ce0.8Sm0.2O2−δ (BCS–SDC, weight ratio 1:1), is reported as an electrolyte material for solid oxide fuel cells (SOFCs). Homogeneous BCS–SDC composite powders are synthesized via a one-step gel combustion method. The BCS and SDC crystalline grains play a role

  15. Planar textile antennas with artificial magnetic conductor for body-centric communications

    Science.gov (United States)

    Kamardin, Kamilia; Rahim, Mohamad Kamal A.; Hall, Peter S.; Samsuri, Noor Asmawati; Latef, Tarik Abdul; Ullah, Mohammad Habib

    2016-04-01

    Two textile antennas namely diamond dipole and coplanar waveguide (CPW) monopole are designed to test the proposed textile artificial magnetic conductor (AMC). Performance comparison including return loss, radiation pattern, and gain between the two antennas above AMC is observed. Results show gain improvement with reduced backlobes when having AMC. Bending and wetness measurements are also conducted. Bending is found not to cause performance disruption, while wetness influences performance distortion. However, once the antennas and AMC dried out, the original performance is retrieved.

  16. Impact of bending strain on critical current of second generation 344 YBCO high Tc coated conductor

    International Nuclear Information System (INIS)

    Second generation YBCO coated conductor has been characterized under various bending stresses. The down slope of the critical current with increasing strain has been supported by the SEM analysis of the tape. The tensile as well as flexural strength of the tape also have been determined experimentally at room temperature. The stress profile of the critically bend strip has been analyzed in ANSYS and the maximum stress on the YBCO strip in the operating condition has been quantified. (author)

  17. Decomposing the electromagnetic response of magnetic dipoles to determine the geometric parameters of a dipole conductor

    Science.gov (United States)

    Desmarais, Jacques K.; Smith, Richard S.

    2016-03-01

    A novel automatic data interpretation algorithm is presented for modelling airborne electromagnetic (AEM) data acquired over resistive environments, using a single-component (vertical) transmitter, where the position and orientation of a dipole conductor is allowed to vary in three dimensions. The algorithm assumes that the magnetic fields produced from compact vortex currents are expressed as a linear combinations of the fields arising from dipoles in the subsurface oriented parallel to the [1, 0, 0], [0, 1, 0], and [0, 0, 1], unit vectors. In this manner, AEM responses can be represented as 12 terms. The relative size of each term in the decomposition can be used to determine geometrical information about the orientation of the subsurface conductivity structure. The geometrical parameters of the dipole (location, depth, dip, strike) are estimated using a combination of a look-up table and a matrix inverted in a least-squares sense. Tests on 703 synthetic models show that the algorithm is capable of extracting most of the correct geometrical parameters of a dipole conductor when three-component receiver data is included in the interpretation procedure. The algorithm is unstable when the target is perfectly horizontal, as the strike is undefined. Ambiguities may occur in predicting the orientation of the dipole conductor if y-component data is excluded from the analysis. Application of our approach to an anomaly on line 15 of the Reid Mahaffy test site yields geometrical parameters in reasonable agreement with previous authors. However, our algorithm provides additional information on the strike and offset from the traverse line of the conductor. Disparities in the values of predicted dip and depth are within the range of numerical precision. The index of fit was better when strike and offset were included in the interpretation procedure. Tests on the data from line 15701 of the Chibougamau MEGATEM survey shows that the algorithm is applicable to situations where

  18. Insulator-insulator and insulator-conductor transitions in the phase diagram of aluminium trichloride

    Directory of Open Access Journals (Sweden)

    Romina Ruberto

    2009-01-01

    Full Text Available We report a classical computer-simulation study of the phase diagram of AlCl3 in the pressure-temperature (p, T plane, showing (i that melting from a layered crystal structure occurs into a molecular liquid at low (p, T and into a dissociated ionic liquid at high (p, T, and (ii that a broad transition from a molecular insulator to an ionic conductor takes place in the liquid state.

  19. The radiation impedance of a current-carrying conductor in a JUNO-like Jovian orbit.

    OpenAIRE

    Sánchez Torres, Antonio; Sanmartín Losada, Juan Ramón

    2010-01-01

    The so-called electrical power generation problem for exploration of the outer planets could be solved deploying an electrodynamic tether. Wave radiation by a conductor carrying a steady current in a polar, highly eccentric, low perijove orbit, as in the planned NASA Juno mission, is considered. The high Jupiter's oblateness produces fast apsidal precession over the meridional plane. In a cold plasma model, radiation occurs in the Alfven and Fast Magnetosonic modes, exhibiting large refractio...

  20. Integral Model of Forces Acting on Long Massive Conductors During Short Circuit

    Czech Academy of Sciences Publication Activity Database

    Karban, P.; Doležel, Ivo; Ulrych, B.

    Košice : Technická univerzita v Košiciach, 2005, s. 1-10. ISBN 80-8073-305-8. [International Scientific Symposium ELEKTROENERGETIKA 2005 /3./. Stará Lesná - High Tatras (SK), 21.09.2005-23.09.2005] Institutional research plan: CEZ:AV0Z20570509 Keywords : dynamic short-circuit forces * long massive conductors * three - phase system Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  1. Textile Diamond Dipole and Artificial Magnetic Conductor Performance under Bending, Wetness and Specific Absorption Rate Measurements

    OpenAIRE

    Kamardin, K.; M.K.A. Rahim; Hall, P S; N. A. Samsuri; M. E. Jalil; M. F. Abd Malek

    2015-01-01

    Textile diamond dipole and Artificial Magnetic Conductor (AMC) have been proposed and tested under wearable and body centric measurements. The proposed antenna and AMC sheet are entirely made of textiles for both the substrate and conducting parts, thus making it suitable for wearable communications. Directive radiation patterns with high gain are obtained with the proposed AMC sheet, hence minimizing the radiation towards the human body. In this study, wearable and body centric measurements ...

  2. Development and fabrication of superconducting hybrid Cable-In-Conduit-Conductor (CICC) for indigenous fusion programme

    International Nuclear Information System (INIS)

    The Atomic Fuels Division has initiated development and fabrication of Cable-In-Conduit-Conductor (CICC) of various configurations, for superconducting fusion grade magnets required for their indigenous Fusion Programme. The process involves development of high grade superconducting multifilamentary wire, multi stage cabling of superconducting as well as copper wires and, finally, jacketing of the cables in SS316LN tubes. The overview of the development and fabrication of CICC is presented in this article. (author)

  3. The Quenched Critical Point for Self-Avoiding Walk on Random Conductors

    Science.gov (United States)

    Chino, Yuki; Sakai, Akira

    2016-05-01

    Following similar analysis to that in Lacoin (Probab Theory Relat Fields 159: 777-808, 2014), we can show that the quenched critical point for self-avoiding walk on random conductors on Z^d is almost surely a constant, which does not depend on the location of the reference point. We provide upper and lower bounds which are valid for all d≥ 1.

  4. The magnetic field inside a layered anisotropic spherical conductor due to internal sources

    Science.gov (United States)

    Nieminen, Jaakko O.; Stenroos, Matti

    2016-01-01

    Recent advances in neuronal current imaging using magnetic resonance imaging and in invasive measurement of neuronal magnetic fields have given a need for methods to compute the magnetic field inside a volume conductor due to source currents that are within the conductor. In this work, we derive, verify, and demonstrate an analytical expression for the magnetic field inside an anisotropic multilayer spherically symmetric conductor due to an internal current dipole. We casted an existing solution for electric field to vector spherical harmonic (VSH) form. Next, we wrote an ansatz for the magnetic field using toroidal-poloidal decomposition that uses the same VSHs. Using properties of toroidal and poloidal components and VSHs and applying magnetic scalar potential, we then formulated a series expression for the magnetic field. The convergence of the solution was accelerated by formulating the solution using an addition-subtraction method. We verified the resulting formula against boundary-element method. The verification showed that the formulas and implementation are correct; 99th percentiles of amplitude and angle differences between the solutions were below 0.5% and 0.5°, respectively. As expected, the addition-subtraction model converged faster than the unaccelerated model; close to the source, 250 terms gave relative error below 1%, and the number of needed terms drops fast, as the distance to the source increases. Depending on model conductivities and source position, field patterns inside a layered sphere may differ considerably from those in a homogeneous sphere. In addition to being a practical modeling tool, the derived solution can be used to verify numerical methods, especially finite-element method, inside layered anisotropic conductors.

  5. Irradiation-induced variation of the insulator-conductor transition of polymer compositions

    International Nuclear Information System (INIS)

    A method for irradiation-induced variation of the insulator-conductor transition of polymer compositions, based on low density polyethylene (LDPE) elastificated with styrenebutadiene rubber (SBR) has been proposed. This method involves high energy irradiation of LDPE-SBR blends loaded with carbon black. The effect of the irradiation dose on the controlled steepness decrease of the transition from high-ohm to low-ohm condition of flexible polymeric compositions has been obtained. (author)

  6. Priority research areas to accelerate the development of practical ultraconductive copper conductors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dominic F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burwell, Malcolm [International Copper Association, Washington, DC (United States); Stillman, H. [International Copper Association, Washington, DC (United States)

    2015-09-01

    This report documents the findings at an Ultraconductive Copper Strategy Meeting held on March 11, 2015 in Washington DC. The aim of this meeting was to bring together researchers of ultraconductive copper in the U.S. to identify and prioritize critical non-proprietary research activities that will enhance the understanding in the material and accelerate its development into practical conductors. Every effort has been made to ensure that the discussion and findings are accurately reported in this document.

  7. Influence of an external stress of irradiation on conductivity of unidimensional organic conductors

    International Nuclear Information System (INIS)

    Irradiation experiments are a convenient way to study effect of defects on transitions of organic conductors: TTF-TCNQ, TSF-TCNQ and their hexamethyl derivative, in particular of a potential bound to a defect in the Peierls field. Defects were studied in the metallic state and deviation to the Matthiessen law were confirmed. Influence of a deformation on electrical conductivity of TTF-TCNQ is shown. Data acquisition is described

  8. Axial compression test on ITER-TFMC conductors at room temperature

    International Nuclear Information System (INIS)

    The superconductor used for the ITER TF Model Coil (TFMC) consists of 720 twisted Nb3Sn-strands and 360 copper strands, which are cabled around a central spiral and are surrounded by a stainless steel jacket. The conductor is heat-treated at 650 deg. C in a stainless steel mould. After cool down to room temperature the conductor is found to be elongated by 0.45 mm/m, which can be attributed to the lower shrinkage of Nb3Sn. This means that the jacket is under tensile stress and the cable under longitudinal compression after cool down. This effect aggravates upon cooling further to the operating temperature. The cable and the jacket can be interpreted as a double spring system, the jacket being the expansion spring and the cable being the compression spring. In order to evaluate and possibly predict such elongations, it is necessary to know the Young's modulus of the cable. Therefore, we investigated samples cut from a dummy conductor, a not heat-treated and a heat-treated TFMC conductor by mechanically compressing them. From the stress-strain diagram the elastic modulus of the cables was determined and found to be about one-tenth of that calculated assuming all components of the cable being fully bonded. The stiffness of the cables turned out to be fairly independent of the state of the cable as all three cables show almost the same modulus. The mechanical compression of the cable is about 8.5 times larger than the measured elongation of the jacket.

  9. Thermal—hydraulic Optimization of Water—cooled Center COnductor Post for Spherical Tokamaks Reactor

    Institute of Scientific and Technical Information of China (English)

    柯严; 吴宜灿; 等

    2002-01-01

    This paper proposes a conceptual structure of segmental water-cooled Center Conductor Post(CCP) to be flexble in installment and replacement.Thermal-hydraulic optimization and sensitivity analysis of key parameters are performed based on a reference fusion transmutation system with 100MW fusion power.Numerical simulation by using a commercial code PHOENICS has been carried out to be close to the thermal-hydraulic analytical results of the CCP mid-part.

  10. Grain growth in Al alloy conductors as a result of rapid annealing

    Science.gov (United States)

    Towner, Janet M.; van de Ven, Evert P.; Hopkins, Craig G.

    1984-01-01

    Aluminum and aluminum alloy thin films were rapidly annealed using high intensity visible light. Under suitable conditions, substantial grain growth was achieved in the Al-Cu and Al-Si-Cu conductors and this grain growth had a beneficial effect on electromigration. Unfortunately, this growth did not occur uniformily across the wafer. A second phenomenon, which resulted from thermal cycling, was the solid phase reduction of SiO2 by the overlying Al film.

  11. Electromagnetic phenomena in a single metallic resistive conductor when a direct current flows. Pinch effect (Hall effect) and field theory

    International Nuclear Information System (INIS)

    In conventional classical electrodynamics, a single metallic resistive conductor is considered to be electrically neutralized in all parts of its interior when a direct current flows. Based on the field theory of electromagnetism, it is thought that Joule's heat is not supplied through a conductor, itself, but from the outside through its surface with the Poynting's vector, which represents the flow of electromagnetic energy. In contrast to this common knowledge, this paper describes a new understanding that the surface of a conductor is positively charged as a thin layer, and that its inner volume is negatively charged due to a pinch effect (Hall effect) on any direct current. As a result, three components of electric- and magnetic-fields appear inside a cylindrical conductor: a radial electric field, an axial electric field, and an angular magnetic field. A non-zero Poynting vector appears inside the conductor towards a radial direction, which supplies Joule's heat inside the conductor, itself. The surface charge density of a positively charged layer and the radial electric field at the surface satisfies a boundary condition. It is then shown that Drude's free-electron model provides a negligible amount of pinch effect so that the conductor is neutralized everywhere, as expressed by common knowledge. However, Sommerfeld's free-electron model based on Pauli's exclusion principle in quantum mechanics provides a reasonable amount of pinch effect so that the conductor has a non-zero charge distribution, as expressed by the new understanding. A field theory of electromagnetism based on the pinch effect is apparently valid as a whole based on the present argument. (author)

  12. Reflection of plane electromagnetic waves from the surface of a perfect conductor moving in an arbitrary direction

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The reflection of plane electromagnetic waves (TE wave and TM wave) from a perfect conductor which moves in an arbitrary direction is investigated. Based on Maxwell's equations and the boundary conditions for moving boundary, the relation between the field vectors of reflected and incident waves, and the reflection coefficient are derived. The energy balance between incident and reflected waves, the force exerted by electromagnetic waves to the moving conductor are also discussed and some new conclusions are suggested for notice.

  13. New Development in the Preparation of Micro/Nano-Wires of Molecular (Magnetic Conductors

    Directory of Open Access Journals (Sweden)

    Lydie Valade

    2010-03-01

    Full Text Available A lot of molecular (magnetic conductors are prepared largely using charge-transfer (CT salts of donor molecules with acceptor molecules or nonmagnetic or magnetic anions such as metal halides and oxides; their CT salts are usually obtained as bulk crystals, which are used to elucidate the electrical conducting (magnetic properties. In contrast, a small number of micro/nano-crystals of the molecular (magnetic conductors, especially micro/nano-wires, are known, of which highly conducting nanowires are necessary as a key component in the development of the next generation of nano-size transistors and spin-transistors. Very recently, we succeeded in preparing highly conductive micro/nano-wires of CT salts between bent donor molecules developed by one of the author’s group and magnetic FeX4– (X = Cl, Br ions: (1 by electrochemical oxidation of the bent donor molecules with a silicon wafer electrode coated with a phospholipid multi-lamellar structure as well as, (ii by electrochemical oxidation of the bent donor molecules with a large arc structure, in the presence of NBu4FeX4 supporting electrolytes. This article reviews template-free and template-assisted methods developed so far for the preparation of micro/nano-wires of molecular (magnetic conductors along with our new methods. The conducting properties of these micro/nano-wires are compared with those of the corresponding bulk crystals.

  14. Development of high strength austenitic stainless steel for conduit of Nb3Al conductor

    International Nuclear Information System (INIS)

    Japan Atomic Energy Research Institute (JAERI) started developing new austenitic stainless steel for a conduit (1 - 2 mm) of a Nb3Al conductor in collaboration with Nippon Steel Corporation (NSC). A high strength austenitic stainless steel is required for a conduit of a Nb3Al conductor to make the best use of superconducting properties of a Nb3Al conductor. JAERI and NSC successfully developed the high strength austenitic stainless steel, JN1 (YS ≥ 1,300 MPa, KIc ≥ 200 MPa√m at 4K) for magnet structures having thick section. However, JN1 is not suitable for a conduit material because elongation of JN1 decreases to less than 10 % due to sensitization during reaction heat treatment for Nb3Al. Therefore, modification of JN1 was performed as a first step to develop a new conduit material which withstands Nb3Al reaction heating. Small trial lots heat-treated at 973 - 1173 K for 2 - 200 hours were prepared and evaluated by Charpy impact test and tensile test at 77 K and 4K. A material having yield strength of 1,390 MPa and elongation of 34 % after aging at 973 K x 200 h are developed up to now. This paper describes requirements on the mechanical properties and status of the development work. In addition, empirical equations to predict 4K yield strength, elongation, and Charpy absorbed energy from 77K data are proposed in this paper

  15. Measurement Of Transverse Jc Profiles Of Coated Conductors Using A Magnetic Knife Of Permanent Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Hanisch, J [Los Alamos National Laboratory; Mueller, F M [Los Alamos National Laboratory; Ashworth, S P [Los Alamos National Laboratory; Coulter, J Y [Los Alamos National Laboratory; Matias, Vlad [Los Alamos National Laboratory

    2008-01-01

    The transverse J{sub c} distribution in YBCO coated conductors was measured nondestructively with high resolution using a 'magnetic knife' made of permanent magnets. The method utilizes the strong depression of J{sub c} in applied magnetic fields. A narrow region of low (including zero) magnetic field, in a surrounding higher field, is moved transversely across the sample in order to reveal the critical-current density distribution. The net resolution of this device is approximately 65 {mu}m, and the J{sub c} resolution is better than 0.5%. A Fourier series inversion process was used to determine the transverse J{sub c} distribution in the sample. The J{sub c} profile was correlated with other sample properties of coated conductors prepared by pulsed laser deposition. Because of its straight-forward and inexpensive design, this J{sub c} imaging technique can be a powerful tool for quality control in coated-conductor production.

  16. Development of a 10 m long superconducting multistrand conductor for power transmission cables

    International Nuclear Information System (INIS)

    A 10 m long HTS cable conductor was stranded with an industrial winding process from 2 km of Ag/Bi2223 tapes. It was installed in a vacuum cryostat and was force cooled by pressurized liquid nitrogen. DC- and AC-load tests were performed while varying the frequency and amplitude of the current. The critical current of the conductor is 5000 A. This model of a power transmission cable demonstrates very low AC losses of 0.8 W m-1 at 2000 Arms/50 Hz measured both with an electric transport and a calorimetric method. The AC losses vary linearly with frequency, P ∝ f, and have a current dependence slightly lower than P ∝ I3. The magnitude of the losses is clearly lower than predicted by the block model version of the Bean model. The model for uniform current distribution (UCD) improves the quantitative description of the losses. From these experiments we conclude that our low loss winding design of the conductor is an early stage of an economical HTS power transmission cable. (author)

  17. Development of cost-effective Nb3Sn conductors for the next generation hadron colliders

    International Nuclear Information System (INIS)

    Significant progress has been made in demonstrating that reliable, efficient high field dipole magnets can be made with Nb3Sn superconductors. A key factor in determining whether these magnets will be a cost-effective solution for the next generation hadron collider is the conductor cost. Consequently, DOE initiated a conductor development program to demonstrate that Nb3Sn can be improved to reach a cost/performance value of $1.50/kA-m at 12T, 4.2K. The first phase of this program was initiated in Jan 2000, with the goal of improving the key properties of interest for accelerator dipole magnets--high critical current density and low magnetization. New world record critical current densities have been reported recently, and it appears that significant potential exists for further improvement. Although new techniques for compensating for magnetization effects have reduced the requirements somewhat, techniques for lowering the effective filament size while maintaining these high Jc values are a program priority. The next phase of this program is focused on reducing the conductor cost through substitution of lower cost raw materials and through process improvements. The cost drivers for materials and fabrication have been identified, and projects are being initiated to demonstrate cost reductions

  18. How filaments can reduce AC losses in HTS coated conductors: a review

    Science.gov (United States)

    Grilli, Francesco; Kario, Anna

    2016-08-01

    Second-generation high-temperature superconductor (HTS) tapes, known also as coated conductors, are very promising tapes for HTS applications, in virtue of their extremely high critical current density, in-field behavior, and mechanical strength. Yet, the extremely large (typically in the range 1000–10 000) width-to-thickness ratio of the superconducting material makes them prone to high power dissipation in the presence of time-varying magnetic fields perpendicular to their flat face—a condition frequently met in several applications. Since the dissipation is directly proportional to the square of the superconductor's width, an obvious way of reducing it is by striating the superconductor into narrow filaments (stripes): in that case, provided that the filaments are electromagnetically uncoupled, the losses are reduced by a factor equal to the number of filaments. In the past two decades, many researchers from groups around the world have tried to apply this idea to practical conductors using different techniques. The aim of this paper is to provide a review of such efforts, focusing on the different approaches to make filamentized conductors, on the effectiveness of the AC loss reduction, and on the applicability of those techniques to long lengths.

  19. Ionization Properties of Molecules Commonly Used for Plasma Processing of Semi-Conductors

    Science.gov (United States)

    Srivastava, S. K.

    2000-01-01

    Two types of processes are involved in plasma processing of semi-conductors. They are: plasma etching or cleaning and plasma deposition of the semi-conducting materials. For plasma etching of semi-conductors mostly halogen containing gases are used as additives to gases such as O2 and N2. For plasma deposition gases such as C2H2, SiH4, Si2H6 have been tested in the past. For an optimal performance of a reactor it is important to model the plasma. In this modeling effort electron impact excitation and ionization cross sections play a central role. For ionization balance calculations values of ionization cross sections are needed. Ion molecule reactions determine the ultimate composition of the plasma. Recently it has been discovered that the by products of many of these plasmas are per fluro hydrocarbons (PFCs) which are highly infrared absorbing species and have long life times in the atmosphere. They cause global warming. A lot of research is being pursued at the present time to find alternative molecules which do not produce global warming gases as the and product of the plasma processing reactor. There is also interest in the ionization and dissociative ionization properties of these molecules from the point view of the plasma abatement of the pollutant gases at the exhaust of the semi-conductor processing reactors. At the conference ionization and dissociative ionization properties of some of these molecules will be presented.

  20. Homogeneous performance and strain tolerance of long Bi-2223 HTS conductors under hoop stress

    Science.gov (United States)

    Miyoshi, Y.; Kitaguchi, H.; Chaud, X.; Debray, F.; Nishijima, G.; Tsuchiya, Y.

    2014-02-01

    Two types of high-strength industrial Bi-2223 conductor, one laminated by copper alloy and the other laminated by stainless steel, have been tested to examine the effect of hoop stress on the transport property. The specimens (˜2 m long) were prepared by winding one layer around a GFRP mandrel and the measurements were made in a liquid helium bath with the hoop stress calculated from the BJR product applied by external magnetic field. A careful measurement wire configuration was necessary to cancel the noise pick-up from the environment for more accurate determination of Ic and n-value. We show for the first time that both conductors showed homogeneous voltage-current characteristics over a long length and degradations with hoop stress occurred uniformly, which is crucial information for the development of HTS magnet technology. The onset of degradation occurred at 200 MPa and 220 MPa, with additional bending stress present from the winding diameter of 108 mm, for copper alloy laminated and stainless steel laminated conductors, respectively. After considering the effect of bending strain, our result agrees well with the previously measured data.

  1. Investigation and optimization of YBa2Cu3O7-δ grain boundaries and coated conductors

    International Nuclear Information System (INIS)

    With increasing misorientation angle grain boundaries strongly reduce the critical current density of high temperature superconductors. For this reason costly techniques are used in production of modern Coated Conductors to induce sharp textures in the polycrystalline superconductor layers. In this dissertation measurements of the critical current density of different grain boundary types are presented showing that out-of-plane grain boundaries exhibit, also in applied magnetic fields, much higher critical current densities than expected. In further analysis of the grain boundaries indications for a microstructural reason of the high critical current densities were found. The high critical current densities of the out-of-plane grain boundaries should in fabrication of Coated Conductors allow for a relaxation of the out-of-plane grain alignment requirements and a concomitant cost reduction. In this work also results of a industrial cooperation with Nexans are presented demonstrating that the critical current density of metal-organic deposited grain boundaries and Coated Conductor layers can be increased by selective Calcium-doping. In the experiments selective Calcium-doping most effectively increased the critical current density of weak spots. (orig.)

  2. High-rate fabrication of YBCO coated conductors using TFA-MOD method

    Science.gov (United States)

    Nakaoka, K.; Yoshizumi, M.; Usui, Y.; Izumi, T.; Shiohara, Y.

    The YBa2Cu3O7-y (YBCO) coated conductors derived from metal-organic deposition (MOD) method using the metal salts of trifluoroacetic acid (TFA) have been developed with high critical current property. The long-length YBCO coated conductors have been fabricated by multi-turn reel-to-reel system. Increasing the thickness per single coating in the multi-turn reel-to-reel system is a cost-effective technique for fabrication of the precursor films in the calcination process. In this work, we have developed a new starting solution consisting of non-fluorine salts of yttrium 4-oxopentanoate and copper 2-ethylhexanoate with focusing on increasing the thickness per single coating for a high-rate fabrication of the YBCO coated conductors by the TFA-MOD method. The critical thickness per single coating of the film fabricated from the new starting solution was 0.54 μm/coat. High critical current of 377 A/cm-width with high critical current density (3.0 MA/cm2) was obtained in the YBCO film fabricated on CeO2 buffered LaMnO3/MgO/Gd2Zr2O-7/HastelloyTM substrates using the new starting solution at the thickness per single coating of 0.42 μm/coat.

  3. Improvement of Production Rate of YBCO Coated Conductors Fabricated by TFA-MOD Method

    Science.gov (United States)

    Nakaoka, K.; Yoshizumi, M.; Usui, Y.; Izumi, T.; Shiohara, Y.

    The metal-organic deposition (MOD) method using trifluoroacetate (TFA) salts is considered to be an effective method for inexpensively fabricating YBa2Cu3O7-y (YBCO) coated conductors with high critical current density property. The long-length TFA-MOD YBCO coated conductors have been fabricated by multi-turn reel-to-reel system. Increasing the thickness per single coating in the multi-turn reel-to-reel system is a cost-effective technique for fabrication of the precursor films in the calcination process since it reduces the number of coatings and shortens the processing time. In this work, we have developed a new starting solution consisting of non-fluorine salts of yttrium propionate and copper 2-ethylhexanoate with focusing on increasing the thickness per single coating for a high-rate fabrication of the YBCO coated conductors by the TFA-MOD method. The critical thickness per single coating of the precursor film fabricated from the new starting solution was improved to 0.44 μm/coat. Furthermore, the addition of diacetoneacrylamide in the new starting solution increased the critical thickness per single coating to 0.79 μm/coat. High critical current of 791 A/cm-width with high critical current density of 2.7 MA/cm2 was obtained using the new starting solution with diacetoneacrylamide at the thickness per single coating of 0.49 μm/coat.

  4. DESIGN, FABRICATION AND TEST OF THE REACT AND WIND, NB(3)SN, LDX FLOATING COIL CONDUCTOR.

    Energy Technology Data Exchange (ETDEWEB)

    SMITH,B.A.; MICHAEL,P.C.; MINERVINI,J.V.; TAKAYASU,M.; SCHULTZ,J.H.; GREGORY,E.; PYON,T.; SAMPSON,W.B.; GHOSH,A.; SCANLAN,R.

    2000-09-17

    The Levitated Dipole Experiment (LDX) is a novel approach for studying magnetic confinement of a fusion plasma. In this approach, a superconducting ring coil is magnetically levitated for up to 8 hours a day in the center of a 5 meter diameter vacuum vessel. The levitated coil, with on-board helium supply, is called the gloating Coil (F-Coil). Although the maximum field at the coil is only 5.3 tesla, a react-and-wind Nb{sub 3}Sn conductor was selected because the relatively high critical temperature will enable the coil to remain levitated while it warms from 5 K to 10 K. Since pre-reacted Nb{sub 3}Sn tape is no longer commercially available, a composite conductor was designed that contains an 18 strand Nb{sub 3}Sn Rutherford cable. The cable was reacted and then soldered into a structural copper channel that completes the conductor and also provides quench protection. The strain state of the cable was continuously controlled during fabrication steps such as: soldering into the copper channel, spooling, and coil winding, to prevent degradation of the critical current. Measurements of strand and cable critical currents are reported, as well as estimates of the effect of fabrication, winding and operating strains on critical current.

  5. Nickel-copper alloy tapes as textured substrates for YBCO coated conductors

    International Nuclear Information System (INIS)

    NiCuCo alloy tape was studied as textured substrates for YBCO coated conductors application. The addition of a small amount of cobalt was pursued in order to enhance the microstructure of the NiCu alloy. The use of different thermal treatments during the recrystallization process permitted to obtain area densities of cube orientation as high as 95%. The substrate was thoroughly characterized by means of x-ray diffraction, EBSD and SEM analyses. Further, the mechanical properties and the magnetic behaviour of this substrate have been investigated and compared with those exhibited by Ni, NiW and NiCu tapes. The suitability of this alloy substrate for YBCO coated conductors has been tested through the deposition of a conventional CeO2/YSZ/CeO2 buffer layer architecture using a Pd transient layer. Apart from passivating Ni-Cu-Co substrate, the use of a Pd transient layer produces a relevant texture sharpening in the out-of-plane orientation and the full width at half maximum of the ω-scan drops from about 90 of NiCuCo to 20 of Pd layer. This sharp texture is transferred to the YBCO film and the results indicate that NiCuCo alloy is a promising alternative substrate for the realization of YBCO coated conductors

  6. Nickel-copper alloy tapes as textured substrates for YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Vannozzi, A; Celentano, G; Angrisani, A; Augieri, A; Colantoni, I; Galluzzi, V; Mancini, A; Rufoloni, A [ENEA, Frascati Research Center, Via E. Fermi 45, 00044 Frascati (Rome) (Italy); Ciontea, L; Petrisor, T; Thalmaier, G [Techn. University of Cluj Napoca, Str. C. Daicoviciu 15, 3400 Cluj-Napoca (Romania); Gambardella, U [INFN-LFN, Via E. Fermi 40, 00044 Frascati (Rome) (Italy)], E-mail: vannozzi@frascati.enea.it

    2008-02-15

    NiCuCo alloy tape was studied as textured substrates for YBCO coated conductors application. The addition of a small amount of cobalt was pursued in order to enhance the microstructure of the NiCu alloy. The use of different thermal treatments during the recrystallization process permitted to obtain area densities of cube orientation as high as 95%. The substrate was thoroughly characterized by means of x-ray diffraction, EBSD and SEM analyses. Further, the mechanical properties and the magnetic behaviour of this substrate have been investigated and compared with those exhibited by Ni, NiW and NiCu tapes. The suitability of this alloy substrate for YBCO coated conductors has been tested through the deposition of a conventional CeO{sub 2}/YSZ/CeO{sub 2} buffer layer architecture using a Pd transient layer. Apart from passivating Ni-Cu-Co substrate, the use of a Pd transient layer produces a relevant texture sharpening in the out-of-plane orientation and the full width at half maximum of the {omega}-scan drops from about 9{sup 0} of NiCuCo to 2{sup 0} of Pd layer. This sharp texture is transferred to the YBCO film and the results indicate that NiCuCo alloy is a promising alternative substrate for the realization of YBCO coated conductors.

  7. Effects of electron-phonon interaction on thermal and electrical transport through molecular nano-conductors

    Energy Technology Data Exchange (ETDEWEB)

    Lü, Jing-Tao, E-mail: jtlu@hust.edu.cn [School of Physics, Huazhong University of Science and Technology, 430074 Wuhan (China); Zhou, Hangbo [Department of Physics and Center for Computational Science and Engineering, National University of Singapore, 117551 Singapore (Singapore); NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, 117456 Singapore (Singapore); Jiang, Jin-Wu [Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University, 200072 Shanghai (China); Wang, Jian-Sheng [Department of Physics and Center for Computational Science and Engineering, National University of Singapore, 117551 Singapore (Singapore)

    2015-05-15

    The topic of this review is the effects of electron-phonon interaction (EPI) on the transport properties of molecular nano-conductors. A nano-conductor connects to two electron leads and two phonon leads, possibly at different temperatures or chemical potentials. The EPI appears only in the nano-conductor. We focus on its effects on charge and energy transport. We introduce three approaches. For weak EPI, we use the nonequilibrium Green’s function method to treat it perturbatively. We derive the expressions for the charge and heat currents. For weak system-lead couplings, we use the quantum master equation approach. In both cases, we use a simple single level model to study the effects of EPI on the system’s thermoelectric transport properties. It is also interesting to look at the effect of currents on the dynamics of the phonon system. For this, we derive a semi-classical generalized Langevin equation to describe the nano-conductor’s atomic dynamics, taking the nonequilibrium electron system, as well as the rest of the atomic degrees of freedom as effective baths. We show simple applications of this approach to the problem of energy transfer between electrons and phonons.

  8. Homogeneous performance and strain tolerance of long Bi-2223 HTS conductors under hoop stress

    International Nuclear Information System (INIS)

    Two types of high-strength industrial Bi-2223 conductor, one laminated by copper alloy and the other laminated by stainless steel, have been tested to examine the effect of hoop stress on the transport property. The specimens (∼2 m long) were prepared by winding one layer around a GFRP mandrel and the measurements were made in a liquid helium bath with the hoop stress calculated from the BJR product applied by external magnetic field. A careful measurement wire configuration was necessary to cancel the noise pick-up from the environment for more accurate determination of Ic and n-value. We show for the first time that both conductors showed homogeneous voltage–current characteristics over a long length and degradations with hoop stress occurred uniformly, which is crucial information for the development of HTS magnet technology. The onset of degradation occurred at 200 MPa and 220 MPa, with additional bending stress present from the winding diameter of 108 mm, for copper alloy laminated and stainless steel laminated conductors, respectively. After considering the effect of bending strain, our result agrees well with the previously measured data. (paper)

  9. Manufacture of mineral-insulated conductor for ITER prototype ELM and VS coil

    International Nuclear Information System (INIS)

    Highlights: • Compaction method is successfully developed for MIC manufacture. • Manufactured MICs show well controlled outer diameter and good electrical properties. • Insulation resistance of all the MICs is higher than 100 GΩ@DC 2500 V. - Abstract: An ITER Organization (IO) Task Agreement (TA) “Final Design and Prototyping of the ITER In-Vessel Coils (IVC) and Feeders” is almost finished by Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). ITER IVCs consist of edge-localized mode (ELM) and vertical stabilization (VS) coils. One prototype Mid-ELM coil complete with 19 brackets brazed with the conductors and one prototype 120° section of upper VS coil with structural components brazed to the conductors have been fabricated. Compaction method is developed successfully for the mineral-insulated conductor (MIC) manufacture. Approximate 110 m Inconel 625 jacket MICs for Mid-ELM prototype coil and 80 m stainless steel 316L jacket MICs for VS prototype coil were manufactured. Most of the copper tubes used for the MICs fabrication failed the ultrasonic testing (UT), but the jacket tubes have good passing rate. Manufacture processes and inspection for the MICs are presented in this paper

  10. Properties and performance of fine-filament bronze-process Nb3Sn conductors

    Science.gov (United States)

    Walker, M. S.; Cutro, J. M.; Zeitlin, B. A.; Ozeryansky, G. M.; Schwall, R. E.; Oberly, C. E.; Ho, J. C.; Woollam, J. A.

    1979-01-01

    Fine-filament bronze-process Nb3Sn superconductors were fabricated to fulfill stringent requirements on critical current under tension in a one-inch bend diameter, current density, stability, and conductor losses. A large fraction of niobium filaments was incorporated in a bronze matrix, and a cable containing 4453 2-micron diameter filaments in each of six strands provided a current density of 85,000 A/sq cm at 10 to the -11th ohm-cm, 10 T, and 4.2 K. The next step was to incorporate copper stabilizer in a conductor with 20,538 filaments. These conductors, fabricated so that bend strains of about 1% would be experienced by the filaments in the one-inch bend, stably carried currents in the 200-500 A range. A quench current of 540 A in a 5-cm bend corresponds to 158,000 A/sq cm in the bronze and filament area, believed to be the highest critical current density reported for multifilamentary Nb3Sn.

  11. Field and temperature scaling of the critical current density in commercial REBCO coated conductors

    CERN Document Server

    Senatore, Carmine; Bonura, Marco; Kulich, Miloslav; Mondonico, Giorgio

    2016-01-01

    Scaling relations describing the electromagnetic behaviour of coated conductors (CCs) greatly simplify the design of REBCO-based devices. The performance of REBCO CCs is strongly influenced by fabrication route, conductor architecture and materials, and these parameters vary from one manufacturer to the others. In the present work we have examined the critical surface for the current density, Jc(T,B,θ ), of coated conductors from six different manufacturers: American Superconductor Co. (US), Bruker HTS GmbH (Germany), Fujikura Ltd. (Japan), SuNAM Co. Ltd. (Korea), SuperOx ZAO (Russia) and SuperPower Inc. (US). Electrical transport and magnetic measurements were performed at temperatures between 4.2 K and 77 K and in magnetic field up to 19 T. Experiments were conducted at three different orientations of the field with respect to the crystallographic c-axis of the REBCO layer, θ = 0deg , 45deg and 90deg , in order to probe the angular anisotropy of Jc. In spite of the large variability of CCs performance, ...

  12. Composite aluminum conductors for pulsed power applications at liquid hydrogen temperatures

    International Nuclear Information System (INIS)

    High-purity, stress-free aluminum has extremely low electrical resistance at liquid hydrocarbon temperatures and strong magnetic fields. A composite conductor constructed with this high-purity, fine-filament material can allow fast current penetration to the filaments embedded in a high-electrical, low-thermal-resistance matrix to minimize loss problems. This composite conductor can be effectively used in pulsed power applications where liquid hydrogen is available, and where liquid helium normally needed for superconducting devices is absent. Major manufacturing concerns require that the matrix material have workability compatible with that of aluminum and practically zero impurity diffusion to ensure the high purity of aluminum filaments in the final product. They report favorable results of a feasibility study on fabricating such a composite conductor. An aluminum-base alloy containing iron and cerium, recently developed as a high-temperature material with dispersion strengthening, was used as the matrix material. It satisfies most of the aforementioned requirements. Using a streamlined die, billets of this alloy with pure aluminum inserts were successfully extruded in steps. Processing parameters were selected based on results of computer-aided processing simulation

  13. Effects of electron-phonon interaction on thermal and electrical transport through molecular nano-conductors

    International Nuclear Information System (INIS)

    The topic of this review is the effects of electron-phonon interaction (EPI) on the transport properties of molecular nano-conductors. A nano-conductor connects to two electron leads and two phonon leads, possibly at different temperatures or chemical potentials. The EPI appears only in the nano-conductor. We focus on its effects on charge and energy transport. We introduce three approaches. For weak EPI, we use the nonequilibrium Green’s function method to treat it perturbatively. We derive the expressions for the charge and heat currents. For weak system-lead couplings, we use the quantum master equation approach. In both cases, we use a simple single level model to study the effects of EPI on the system’s thermoelectric transport properties. It is also interesting to look at the effect of currents on the dynamics of the phonon system. For this, we derive a semi-classical generalized Langevin equation to describe the nano-conductor’s atomic dynamics, taking the nonequilibrium electron system, as well as the rest of the atomic degrees of freedom as effective baths. We show simple applications of this approach to the problem of energy transfer between electrons and phonons

  14. Conductor development for a wide bore 10 T $Nb_{3}Sn$ model dipole magnet

    CERN Document Server

    den Ouden, A; ten Kate, H H J; Kirby, G A; Taylor, T M; Siegel, N

    2000-01-01

    An 87.8 mm bore single aperture 10 T Nb/sub 3/Sn model dipole magnet is under development as a next step in the realization of high-field Nb/sub 3/Sn dipole magnets. The magnet is a 2 layer cos( theta )- dipole model as an alternative for the proposed NbTi D1 beam separator magnets for the LHC. After completion of the general magnetic and mechanical design, all attention is focused on the manufacturing and cabling of a novel powder-in-tube Nb/sub 3/Sn conductor. This Nb/sub 3/Sn conductor is characterized by a high non- Cu J/sub c/ of 2680 A/mm/sup 2/ at 10 T with an effective filament size of about 20 mu m. Cabling should result in a Rutherford type of cable exhibiting a moderate J/sub c/ degradation due to the cabling process itself, a low transverse stress sensitivity and a controllable minimum value of R/sub c/. The conductor development program is presented and the results are evaluated. Progress on the actual realization of the coils is briefly described. (9 refs).

  15. Development of productive process for long coated conductors by EB evaporation

    International Nuclear Information System (INIS)

    We have installed original EB evaporation system and verified the performance of CeO2 buffer layers fabricated by EB evaporation method in the YBCO coated conductor in comparison with those fabricated by PLD method. The Ic values of YBCO coated conductors obtained by same deposition for CVD-YBCO were 135 A (EB-CeO2 sample) and 126 A (PLD-CeO2 sample). Though the values of Δφ for the EB-CeO2 layer and PLD-CeO2 layer were different, the Ic values of the YBCO were about the same. This result was shown that the CeO2 layer of Δφ = 10 deg. obtained by EB evaporation was equivalent in performance for YBCO coated conductors to the CeO2 layer of Δφ = 4 deg. obtained by PLD method. The influence of CeO2 film thickness for high speed production was examined. The Ic did not show the remarkable difference with the reduction of CeO2 film thickness. The range of the Ic was only about 20% of the maximum Ic value, regardless of the progress by 5 times in the production speed of CeO2 buffer layers

  16. Measurement of Resistance and Strength of Conductor Splices in the MICE Coupling Magnets

    International Nuclear Information System (INIS)

    The superconducting magnets for the Muon Ionization Cooling Experiment [1] (MICE) use a copper based Nb-Ti conductor with un-insulated dimensions of 0.95 by 1.60 mm. There may be as many as twelve splices in one MICE superconducting coupling coil. These splices are to be wound in the coil. The conductor splices produce Joule heating, which may cause the magnet to quench. A technique of making conductor splices was developed by ICST. Two types of 1-meter long of soldered lap-joints have been tested. Side-by-side splices and up-down one splices were studied theoretically and experimentally using two types of soft solder made of eutectic tin-lead solder and tin-silver solder. The resistances of the splices made by ICST were tested at LBNL at liquid helium temperatures over a range of magnetic fields up to 5 T. The breaking strength of 250 mm long splices was also measured at room temperature and liquid nitrogen temperature.

  17. Estimation of magnetic relaxation property for CVD processed YBCO-coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Y.; Kiuchi, M.; Otabe, E.S. [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502 (Japan); Matsushita, T., E-mail: matusita@cse.kyutech.ac.j [Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, 680-4 Kawazu, Iizuka, Fukuoka 820-8502 (Japan); Shikimachi, K.; Watanabe, T.; Kashima, N.; Nagaya, S. [Chubu Electric Power Co., Inc., 20-1, Kitasekiyama, Ohdaka-cho, Midori-ku, Nagoya 459-8522 (Japan)

    2010-11-01

    Ion Beam Assist Deposition/Chemical Vapor Deposition(IBAD/CVD)-processed YBCO-coated conductors with high critical current density J{sub c} at high magnetic fields are expected to be applied to superconducting equipments such as superconducting magnetic energy storage (SMES). For application to superconducting magnet in SMES one of the most important properties for superconductors is the relaxation property of superconducting current. In this paper, the relaxation property is investigated for IBAD/CVD-processed YBCO-coated conductors of the superconducting layer in the range of 0.18-0.90 {mu}m. This property can be quantitatively characterized by the apparent pinning potential, U{sub 0}*. It is found that U{sub 0}* takes a smaller value due to the two-dimensional pinning mechanism at high magnetic fields for conductor with thinner superconducting layer. Although U{sub 0}* decreases with increasing thickness at low magnetic fields at 20 K, it increases at high magnetic fields. The results are theoretically explained by the model of the flux creep and flow based on the dimensionality of flux pinning. Scaling analysis is examined for the dependence of U{sub 0}{sup *} on the magnetic field, temperature and the layer thickness.

  18. Estimation of magnetic relaxation property for CVD processed YBCO-coated conductors

    Science.gov (United States)

    Takahashi, Y.; Kiuchi, M.; Otabe, E. S.; Matsushita, T.; Shikimachi, K.; Watanabe, T.; Kashima, N.; Nagaya, S.

    2010-11-01

    Ion Beam Assist Deposition/Chemical Vapor Deposition(IBAD/CVD)-processed YBCO-coated conductors with high critical current density Jc at high magnetic fields are expected to be applied to superconducting equipments such as superconducting magnetic energy storage (SMES). For application to superconducting magnet in SMES one of the most important properties for superconductors is the relaxation property of superconducting current. In this paper, the relaxation property is investigated for IBAD/CVD-processed YBCO-coated conductors of the superconducting layer in the range of 0.18-0.90 μm. This property can be quantitatively characterized by the apparent pinning potential, U0∗. It is found that U0∗ takes a smaller value due to the two-dimensional pinning mechanism at high magnetic fields for conductor with thinner superconducting layer. Although U0∗ decreases with increasing thickness at low magnetic fields at 20 K, it increases at high magnetic fields. The results are theoretically explained by the model of the flux creep and flow based on the dimensionality of flux pinning. Scaling analysis is examined for the dependence of U0∗ on the magnetic field, temperature and the layer thickness.

  19. Reversible axial-strain effect in Y-Ba-Cu-O coated conductors

    International Nuclear Information System (INIS)

    The recently discovered reversible strain effect in Y-Ba-Cu-O (YBCO) coated conductors contrasts with the general understanding that the effect of strain on the critical-current density Jc in practical high-temperature superconductors is determined only by crack formation in the ceramic component. Instead of having a constant Jc as a function of strain before an irreversible drop when cracks form in the superconductor, Jc in YBCO coated conductors can decrease or increase reversibly with strain over a significant strain range up to an irreversible strain limit. This reversible effect is present in samples fabricated either with rolling-assisted biaxially textured Ni-W substrates or with ion-beam-assisted deposition on Hastalloy substrates. The reversibility of Jc with strain is observed for thin as well as thick YBCO films, and at two very different temperatures (76 and 4 K). The reversible effect is dependent on temperature and magnetic field, thus indicating its intrinsic nature. We also report an enhancement of the irreversible strain limit εirr where the reversible strain effect ends and YBCO cracking starts. The value of εirr increases from about 0.4% to more than 0.5% when YBCO coated conductors are fabricated with an additional Cu protection layer

  20. Thermo-Hydraulic behaviour of dual-channel superconducting Cable-In-Conduit Conductors for ITER

    International Nuclear Information System (INIS)

    In an effort to optimise the cryogenics of large superconducting coils for fusion applications (ITER), dual channel Cable-In-Conduit Conductors (CICC) are designed with a central channel spiral to provide low hydraulic resistance and faster helium circulation. The qualitative and economic rationale of the conductor central channel is here justified to limit the superconductor temperature increase, but brings more complexity to the conductor cooling characteristics. The pressure drop of spirals is experimentally evaluated in nitrogen and water and an explicit hydraulic friction model is proposed. Temperatures in the cable must be quantified to guarantee superconductor margin during coil operation under heat disturbance and set adequate inlet temperature. Analytical one-dimensional thermal models, in steady state and in transient, allow to better understand the thermal coupling of CICC central and annular channels. The measurement of a heat transfer characteristic space and time constants provides cross-checking experimental estimations of the internal thermal homogenization. A simple explicit model of global inter-channel heat exchange coefficient is proposed. The risk of thermosyphon between the two channels is considered since vertical portions of fusion coils are subject to gravity. The new hydraulic model, heat exchange model and gravitational risk ratio allow the thermohydraulic improvement of CICC central spirals. (author)