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Sample records for re-123 coated conductors

  1. Measurement of in-plane magnetic relaxation in RE-123 coated conductors by use of scanning Hall probe microscopy

    NASA Astrophysics Data System (ADS)

    Shiohara, K.; Higashikawa, K.; Inoue, M.; Kiss, T.; Iijima, Y.; Saitoh, T.; Yoshizumi, M.; Izumi, T.

    2013-01-01

    We have investigated electric field criterion of in-plane critical current density in a coated conductor characterized by scanning Hall-probe microscopy (SHPM). From remanent field distribution and its relaxation measurements, we could obtain critical current distribution and induced electric field simultaneously by considering the Biot-Savart law and the Faraday’s law, respectively. These results lead us to evaluate a distribution of local critical current density and the corresponding criterion of electric field. As a result, it was found that the electric field criterion for the SHPM analysis was several orders lower than that used in the conventional 4-probe resistive method. However, the data point obtained by the SHPM shows good agreement with E-J curve analytically extended from the measurements by the 4-probe method. This means that we could characterize in-plane distribution of critical current density in a coated conductor at an electric field criterion quantitatively by this method in a nondestructive manner. These findings will be very important information since the uniformity of local critical current density in a coated conductor at extremely low electric fields is a key issue (1) especially for DC applications, (2) for quality control of coated conductors, and (3) for the standardization of the characterization of critical current among different methods.

  2. Sample and length-dependent variability of 77 and 4.2 K properties in nominally identical RE123 coated conductors

    NASA Astrophysics Data System (ADS)

    Rossi, L.; Hu, X.; Kametani, F.; Abraimov, D.; Polyanskii, A.; Jaroszynski, J.; Larbalestier, D. C.

    2016-05-01

    We present a broad study by multiple techniques of the critical current and critical current density of a small but representative set of nominally identical commercial RE123 (REBa2Cu3O7-δ , RE = rare Earth, here Y and Gd) coated conductors (CC) recently fabricated by SuperPower Inc. to the same nominal high pinning specification with BaZrO3 and RE2O3 nanoprecipitate pinning centers. With high-field low-temperature applications to magnet technology in mind, we address the nature of their tape-to-tape variations and length-wise I c inhomogeneities by measurements on a scale of about 2 cm rather than the 5 m scale normally supplied by the vendor and address the question of whether these variations have their origin in cross-sectional or in vortex pinning variations. Our principal method has been a continuous measurement transport critical current tool (YateStar) that applies about 0.5 T perpendicular and parallel to the tape at 77 K, thus allowing variations of c-axis and ab-plane properties to be clearly distinguished in the temperature and field regime where strong pinning defects are obvious. We also find such in-field measurements at 77 K to be more valuable in predicting 4.2 K, high-field properties than self-field, 77 K properties because the pinning centers controlling 77 K performance play a decisive role in introducing point defects that also add strongly to J c at 4.2 K. We find that the dominant source of I c variation is due to pinning center fluctuations that control J c, rather than to production defects that locally reduce the active cross-section. Given the 5-10 nm scale of these pinning centers, it appears that the route to greater I c homogeneity is through more stringent control of the REBCO growth conditions in these Zr-doped coated conductors.

  3. High Critical Current Coated Conductors

    SciTech Connect

    Paranthaman, M. P.; Selvamanickam, V.

    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.

  4. National accelerated coated conductor initiative

    NASA Astrophysics Data System (ADS)

    Hawsey, Robert A.; Peterson, Dean E.

    2002-01-01

    The national Accelerated Coated Conductor Initiative (ACCI) is committed to assuring continued U.S. leadership in the development of high-temperature superconducting (HTS) wire for electric power and other applications of national interest. Increased energy efficiency, power density, and power-to-weight ratio are just a few of the tangible benefits that will be possible if today's meter lengths of HTS wire based upon the compound yttrium-barium-copper-oxygen (YBCO) can be scaled up by U.S. industry to kilometer lengths. This paper presents an evaluation of the current state of the development of coated conductor technology and a vision for its future. The challenges that U.S. Department of Energy (DOE) laboratories and their industrial and university partners face will be presented against the backdrop of the history of superconductivity program achievements. It is the purpose of this initiative to accelerate the development, commercialization, and application of high temperature superconductors through joint efforts among DOE laboratories, American industry, and universities, so that future challenges of the electric power industry can be met. Based on their advances in HTS coated conductor development in a program funded by the DOE's Office of Power Technologies, Los Alamos and Oak Ridge National Laboratories lead and support this effort by improving their own capabilities, including equipment, facilities, and technical expertise. Each laboratory has, in 2001, acquired new laboratory space, new capital equipment, and new personnel with the goal of working closely with U.S. companies to take technologies invented in the labs and demonstrated in 1-m lengths and transfer these technologies to the commercial sector. The present status of the performance of the second-generation YBCO wires will be described, and the future plans of the national laboratories will be presented. Opportunities for collaboration are discussed, as well. .

  5. Coated Conductor Processing: Copper Stabilizer

    NASA Astrophysics Data System (ADS)

    Floegel-Delor, U.; Riedel, T.; Wippich, D.; Goebel, B.; Rothfeld, R.; Schirrmeister, P.; Werfel, F. N.; Usoskin, A.; Rutt, A.

    We present here a report about a copper stabilizer processing unit and the function on IBAD - HPLD coated conductor properties. A continuous reel - to- reel Cu plating stabilizer manufacturing technology was developed and will be transferred to Bruker HTS. The quality and performance of one- side and double- side 20 μm Cu layers are evaluated with respect to critical current behavior and conductor joint fabrication. By current pulse plating technology in copper sulphate CuSO4 we have gained to optimize the plating speed to more than 30 m/h by variation the electrical, electrode and solution parameters. With the new 6 m long Cu reel plating unit improved production yield and reproducible Cu stabilizer performance is demonstrated. The non-vacuum deposition unit has a high flexibility in processing a homogeneous Cu stabilizer of thickness of 5 - 50 μm. Using the Cu layer face -to -face joints with resistances of 10-7 Ωcm2 level by standard soldering are becoming routine. We will provide an overall analysis of our construction and results in the PLD Cu - HTS hybrid conductor engineering and processing.

  6. Resistive coating for current conductors in cryogenic applications

    DOEpatents

    Hirayama, Chikara; Wagner, George R.

    1982-05-18

    This invention relates to a resistive or semiconducting coating for use on current conductors in cryogenic applications. This includes copper-clad superconductor wire, copper wire used for stabilizing superconductor magnets, and for hyperconductors. The coating is a film of cuprous sulfide (Cu.sub.2 S) that has been found not to degrade the properties of the conductors. It is very adherent to the respective conductors and satisfies the mechanical, thermal and electrical requirements of coatings for the conductors.

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

    NASA Astrophysics Data System (ADS)

    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

  8. Conversion of Oxyfluoride Based Coated Conductors

    SciTech Connect

    Dan Wesolowski

    2006-11-01

    Direct measurements of HF pressure in equilibrium with the film during the BaF2 process are sorely needed. It is the HF partial pressure that governs the rate at which the film composition is changing and is, therefore, an important factor in controlling the composition/time trajectory of the film. Establishing the composition/time trajectory of both MOD-derived and e-beam derived films for a given set of conditions is another goal for the project. These studies will provide a fundamental understanding of the ex situ process for producing coated conductors.

  9. Coated conductors for power applications: materials challenges

    NASA Astrophysics Data System (ADS)

    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.

  10. Maximum permissible voltage of YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z.; Hong, Z.; Wang, D.; Zhou, H.; Shen, X.; Shen, C.

    2014-06-01

    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 (Ic) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the Ic 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.

  11. Visualization of non-uniform current flow in coated conductors by scanning Hall-probe magnetic microscopy

    NASA Astrophysics Data System (ADS)

    Abiru, K.; Honda, Y.; Inoue, M.; Kiss, T.; Iijima, Y.; Kakimoto, K.; Saitoh, T.; Nakao, K.; Shiohara, Y.

    2009-10-01

    We have visualized non-uniform current flow in RE123 coated conductors by using a scanning Hall-probe magnetic microscopy (SHPM). Newly developed SHPM system allows us to measure two-dimensional magnetic field distribution with high spatial resolution in micro-meter scale. Corresponding current density distribution can be obtained from the magnetic field image by solving inverted Biot-Savart’s law. One of the most important advantages of the present system is to visualize the current density distribution in practical high transport current and also in wide scanning area. For example, the system has current leads with large capacity up to 500 A, and the operating distance can be 15 cm by 15 cm with a micro-meter step distance. Using the SHPM system, we have successfully visualized current density distributions in the coated conductor, and clarified different kinds of non-uniform current flow. Those insights are very useful to identify local defects as well as non-uniform tape quality. These results indicate that the SHPM system is a powerful diagnostic tool not only to observe spatial inhomogeneities of transport property but also to understand their reason in practical coated conductors.

  12. Fabrication of Filamentary YBCO Coated Conductor by Inkjet Printing

    SciTech Connect

    List III, Frederick Alyious; Kodenkandath, Thomas; Rupich, Marty

    2007-01-01

    Inkjet printing is a potentially low cost, high rate method for depositing precursors for filamentary YBCO coated conductors. The method offers considerable flexibility of filament pattern, width, and thickness. Using standard solution precursors and RABiTSTM substrates, the printing, processing, and properties of some inkjet-derived filamentary YBCO coated conductors for Second Generation (2G) wire are demonstrated on a laboratory scale. Some systematic variations of growth rate and critical transport current with filament width are observed and discussed.

  13. Persistent currents in a magnetic bearing with coated conductors

    NASA Astrophysics Data System (ADS)

    Sass, F.; Ramos de Castro, André; Gonçalves Sotelo, Guilherme; de Andrade, R.

    2015-11-01

    Superconducting magnetic bearings are normally built with bulk superconductors. Since coated conductors properties are far superior, we have proposed in a previous work the replacement of bulks for stacks of 2G wires in magnetic levitation devices. A major limitation of this replacement lies in the fact that the induced current is constrained in narrow loops along the available commercial widths of 2G wires. This work presents a technique to achieve wider loops of persistent current without the need of increasing the coated conductors width. As a result, the use of 2G wires in magnetic bearings took a step towards its economical feasibility.

  14. Numerical analysis of quench in coated conductors with defects

    NASA Astrophysics Data System (ADS)

    Liu, Wenbin; Yong, Huadong; Zhou, Youhe

    2016-09-01

    When the superconductor is subjected to local thermal perturbations, a large amount of joule heat may be generated in the conductor, which may lead to a quench. In a quench event, a normal zone irreversibly spreads throughout the conductor leading to failure of the superconducting device. In this paper, we will discuss the one-dimensional quench behavior in the coated conductors with internal defects or interface defects. Based on the numerical procedure given in the previous works, the normal zone propagation is studied by using the finite difference method. The numerical results are presented to discuss the normal zone propagation. We consider the effect of internal defect on the nonuniform temperature propagation. For the conductor with interface defects, it can be found that the normal zone propagation velocity is increased by defects.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Highlights in R&D for coated conductors in Japan

    NASA Astrophysics Data System (ADS)

    Shiohara, Yuh; Kitoh, Yutaka; Izumi, Teruo

    2006-10-01

    The current 5-year national project since 2003 for development of coated conductors (CC) using Y-system superconductors has passed for almost a half term and has achieved satisfactory results. In this paper, the current status and the future prospect are reviewed. The group of Fujikura Ltd. and SRL-ISTEC has worked on the long tape with high performance in the PLD-YBCO superconducting tapes on the IBAD-Gd2Zr2O7 buffered substrates. The highest value on the product of Ic × L in the world was marked by the result which were 51,940 A m (212 m × 245 A) by the SRL group. Fujikura Ltd. also realized the longest tape of 200 m with a reasonable high Ic value of 100 A. The values have been steadily improved and the trend is going to be continued, since the large equipments for both IBAD and PLD have been installed, and ready to work on large tapes with a high production rate. In another group, the long tape processing has been developed focusing on lowering the production cost. The extremely high Ic value of 470 A was obtained in the film by the TFA-MOD method on CeO2 (PLD)/GZO(IBAD)/hastelloy substrate. In the efforts for the long tape in the process, a 25 m long tape with its Ic value of 100 A was realized by a continuous reel-to-reel system. Additionally, 100 m class long tapes were also obtained by the MOCVD and PLD-HoBCO processes. Both groups are aiming to achieve the final goals of 500 m long tapes with the high Ic value of 300 A/cm-w by the production rate of 5 m/h. Furthermore, the feasibility study for applications using coated conductors has been already started due to the above-mentioned success of long tape production. Several kinds of coils using long coated conductors such as a solenoid and a pancake coils and the spiral shaped conductors for cable applications were firstly made. Reasonable high performances were confirmed in the trials. For the future plans of coated conductor applications, the following power devices using coated conductors have been

  17. Ac loss reduction of multilayer superconducting power transmission cables by using narrow coated conductors

    NASA Astrophysics Data System (ADS)

    Amemiya, Naoyuki; Li, Quan; Ito, Kaoru; Takeuchi, Katsutoku; Nakamura, Taketsune; Okuma, Takeshi

    2011-06-01

    The ac loss characteristics of coated conductors are dominated by the magnetic field component normal to their superconductor layer. Multilayer cables as well as monolayer cables consisting of 4 mm-wide coated conductors (named 4 mm cables) and those consisting of 2 mm-wide coated conductors (named 2 mm cables) were designed, and numerical electromagnetic field analyses were performed in their cross sections to calculate their ac losses. Trapezoidal lateral critical current density Jc distributions with shoulders as well as uniform ones were assumed in coated conductors for the analyses. The former models the degraded Jc near the edges of coated conductors. In the case of the monolayer, the calculated ac losses of the 2 mm cables were comparable to those of the 4 mm cables. In the cases of the multilayers, the calculated ac losses of the 2 mm cables were obviously less than those of the 4 mm cables. The degraded Jc near the edges of coated conductors more seriously affects the ac loss characteristics of the 2 mm cables than those of the 4 mm cables. However, even if we consider the influence of the degraded Jc near the edges of coated conductors, 2 mm-wide coated conductors are more profitable than 4 mm-wide coated conductors in multilayer cables from the viewpoint of ac loss reduction.

  18. High current DyBCO-ROEBEL Assembled Coated Conductor (RACC)

    NASA Astrophysics Data System (ADS)

    Goldacker, W.; Nast, R.; Kotzyba, G.; Schlachter, S. I.; Frank, A.; Ringsdorf, B.; Schmidt, C.; Komarek, P.

    2006-06-01

    Low AC loss high transport current HTS cables (>1 kA) are required for application in transformers, generators and are considered for future generations of fusion reactors coils. 2G coated conductors are suitable candidates for high field application at quite high operation temperatures of 50-77 K, which is crucial precondition for economical cooling costs. As a feasibility study we present the first ROEBEL bar cable of approx. 35 cm length made from industrial DyBCO coated conductor (THEVA GmbH, Germany). Meander shaped ROEBEL strands of 4 mm width with a twist pitch of 180 mm were cut from 10 mm wide CC tapes using a specially designed tool. The strands carried in average 157 Amps/cm-width DC and were assembled to a subcable with 5 strands and a final cable with 16 strands. The 5 strand cable was tested and carried a transport current of >300 Amps DC at 77 K, equivalent to the sum of the individual strand transport critical currents. The 16 strand cable carried 500 A limited through heating effects and non sufficient stabilisation and current sharing. A pulse current load indicated a current carrying potential of >1 kA for the 16 strand cable.

  19. Application of solution deposition techniques to coated conductor fabrication

    NASA Astrophysics Data System (ADS)

    Sathyamurthy, Srivatsan

    2000-12-01

    Coated conductors offer a viable alternative to the BSCCO PIT tapes. However, at the current juncture, results are being reported for conductors with buffer layers and superconductor layers processed using conventional thin film deposition which are vacuum based. Also these conductors are fabricated using four or five buffer layers between the superconductor and the metal substrate. These aspects of the fabrication route drive the cost of the process to prohibitively high values. This work is directed at the development of fabrication routes for cube textured nickel substrates, and metallorganic decomposition (MOD) routes for buffer layers and Y123 layers using simple solution based techniques which can be readily scaled. Studies of cube texturing of nickel using rolling and recrystallization showed that it is possible to produce textured nickel substrates with a FWHM of 8--10°. The substrate quality of the nickel is determined by the purity of the cube texture and the cleanliness of the surface. Processing of oriented buffer layers of barium zirconate and strontium titanate using simple metal organic decomposition routes have been studied. These processes, which use precursor solutions made by dissolution of simple acetates in common solvents like acetic acid and methanol, produce highly oriented buffer layers even when processed in a partially reducing atmosphere. Therefore, these MOD routes for buffer layer processing are compatible with nickel substrates and produce buffer layers oriented as sharply as the underlying nickel substrate. Y123 processing using fluorinated precursors, as in the TFA process, effectively circumvents the BaCO3 problem associated with most MOD routes for Y123 processing. This route, under optimized process conditions, yields Y123 films with Jc of the order of 106 A/cm2 on single crystal substrates. Studies of the compatibility of the TFA process with the MOD buffer layers showed that current density of the order of 106 A/cm 2 can be

  20. Status of high transport current ROEBEL assembled coated conductor cables

    NASA Astrophysics Data System (ADS)

    Goldacker, Wilfried; Frank, Antje; Kudymow, Andrej; Heller, Reinhard; Kling, Andrea; Terzieva, Stanimira; Schmidt, Curt

    2009-03-01

    Assembling coated conductors (CC) into flat ROEBEL bars (RACC cable) was introduced in 2005 by the authors as a practicable method of reaching high transport currents in a low AC loss cable, which is a cable design suited for application in windings. The transport current of 1.02 kA in self-field at 77 K achieved so far, however, is still too low for several applications in electrical machinery such as larger transformers and generators/motors. A new cable concept for further increased currents was presented just recently. The goal of the new design was primarily to demonstrate the possibility of strongly increased transport currents without changing the important cable features for low AC losses. such as, for example, the transposition length of the strands. We present detailed investigations of the properties of this progressed cable design, which has threefold layered strands, an unchanged transposition pitch of 18.8 cm and finally the application of 45 coated conductors in the cable. A 1.1 m long sample (equivalent to six transposition lengths) was prepared from commercial Cu stabilized coated conductors purchased from Superpower. The measured new record DC transport current of the cable was 2628 A at 77 K in self-field (5 µV cm-1 criterion). The use of three slightly different current carrying batches of strand material (± 10%) was a special feature of the cable, which allowed for interesting investigations of current redistribution effects in the cable, by monitoring a representative strand of each batch during the critical current measurement. Although current redistribution effects showed a complex situation, the behaviour of the cable was found to be absolutely stable under all operational conditions, even above the critical current. The high self-field degradation of the critical current reached the order of 60% at 77 K, and could be modelled satisfactory with calculations based on a proven Biot-Savart-law approach, adapted to the specific boundary

  1. Impact of Inhomogeneities in HTS Coated Conductors for Resistive FCLs

    NASA Astrophysics Data System (ADS)

    Colangelo, Daniele; Memiaghe, Steeve; Lacroix, Christian; Sirois, Frédéric; Dutoit, Bertrand

    Several issues remain to be addressed for the commercial development of ResistiveFault Current Limiters based on superconducting technologies (RFCL). In particular, the inhomogeneity of high temperature superconducting coated conductors (HTS-CC) combined with the diffculty to predict RFCLs behaviour when interfaced with the existing electrical grid represents an important bottleneck that limits their competitiveness on the electrical market. In order to study the influence of the local inhomogeneity of the HTS tape on the global effective performance of an RFCL, a modular equivalent circuit model has been developed using SimPowerSystemsTM. The model implements an inhomogeneity distribution based on statistical data and takes into account the thermal conduction between different zones of the HTS-CC. It has been calibrated with experimental measurements and finite element simulations. The model can be used to study various scenarios common to power systems, such as transformer in-rush currents, motor starts, etc.

  2. Solderability Study of RABiTS-Based YBCO Coated Conductors

    SciTech Connect

    Zhang, Yifei; Duckworth, Robert C; Ha, Tam T; Gouge, Michael J

    2011-01-01

    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.

  3. All MOD buffer/YBCO approach to coated conductors

    NASA Astrophysics Data System (ADS)

    Parans Paranthaman, M.; Sathyamurthy, S.; Heatherly, L.; Martin, P. M.; Goyal, A.; Kodenkandath, T.; Li, X.; Thieme, C. L. H.; Rupich, M. W.

    2006-10-01

    RABiTS based metal-organic deposition (MOD) buffer/YBa2Cu3O7-δ (YBCO) approach has been considered as one of the potential, low-cost approaches to fabricate high performance second generation coated conductors. The most commonly used RABiTS architectures consisting of a starting template of biaxially textured Ni-W (5 at.%) substrate with a seed layer of Y2O3, a barrier layer of YSZ, and a CeO2 cap. In this three layer architecture, all the buffers are deposited using physical vapor deposition (PVD) techniques. Using these PVD deposited templates, 0.8-μm thick MOD-YBCO films with an Ic (critical current) of 250 A/cm have been achieved routinely in short lengths. We have developed a low-cost, non-vacuum, MOD process to grow epitaxial buffer layers on textured Ni-5W substrates. The main challenge in this effort is to match the performance of MOD templates to that of PVD templates. We have recently shown that the properties of MOD-La2Zr2O7 (LZO) layers can be improved by inserting a thin Y2O3 seed layer. Using MOD-CeO2 cap layers, we have demonstrated the growth of high performance MOD-YBCO films with an Ic of 200 A/cm-width on MOD-La2Zr2O7/Y2O3/Ni-5W substrates. This approach could potentially decrease the overall cost of the coated conductor fabrication.

  4. All MOD Buffer/YBCO Approach to Coated Conductors

    SciTech Connect

    Paranthaman, Mariappan Parans; Sathyamurthy, Srivatsan; Heatherly Jr, Lee; Martin, Patrick M; Goyal, Amit; Kodenkandath, Thomas; Li, Xiaoping; Thieme, C. L. H.; Rupich, Marty

    2006-01-01

    RABiTS based metal-organic deposition (MOD) buffer/YBa2Cu3O7-d (YBCO) approach has been considered as one of the potential, low-cost approaches to fabricate high performance second generation coated conductors. The most commonly used RABiTS architectures consisting of a starting template of biaxially textured Ni-W (5 at.%) substrate with a seed layer of Y2O3, a barrier layer of YSZ, and a CeO2 cap. In this three layer architecture, all the buffers are deposited using physical vapor deposition (PVD) techniques. Using these PVD deposited templates, 0.8-{mu}m thick MOD-YBCO films with an Ic (critical current) of 250 A/cm have been achieved routinely in short lengths. We have developed a low-cost, non-vacuum, MOD process to grow epitaxial buffer layers on textured Ni-5W substrates. The main challenge in this effort is to match the performance of MOD templates to that of PVD templates. We have recently shown that the properties of MOD-La2Zr2O7 (LZO) layers can be improved by inserting a thin Y2O3 seed layer. Using MOD-CeO2 cap layers, we have demonstrated the growth of high performance MOD-YBCO films with an Ic of 200 A/cm-width on MOD-La2Zr2O7/Y2O3/Ni-5W substrates. This approach could potentially decrease the overall cost of the coated conductor fabrication.

  5. High-temperature-superconductor coated conductors: technical progress in Japan

    NASA Astrophysics Data System (ADS)

    Iijima, Yasuhiro; Matsumoto, Kaname

    2000-01-01

    It is now a widespread view that a high-Jc superconducting wire with a high performance under strong magnetic fields at liquid-nitrogen temperature needs to be realized by the material Y-123. However, because of the weak linking nature of this material, the fabrication of the wire must be based on a coated-conductor process to achieve a highly textured Y-123 thin film on a long starting wire tape. Various attempts to obtain a textured substrate with sizable length have been made by various methods, with or without the aid of buffer layers. Approaches to the fabrication of an epitaxial thin film of Y-123 have also been made from vapour, liquid, or solid phases by different methods. Therefore, combinations of these proposed processes in each category have led to several promising on-going worldwide approaches to achieve the realization of practical coated superconducting wires in the near future. This review focuses on the most outstanding achievements in Japan.

  6. Interface morphological stability of unidirectionally solidified RE123 superconductor

    SciTech Connect

    Sumida, M.; Umeda, T.; Shiohara, Y.

    1998-12-31

    A simple model is proposed to analyze the interface stability of the RE123 superconductor in accordance with the constitutional supercooling criterion. As the single crystal growth of the 123 phase is largely dependent on the growth interface stability, a quantitative analysis has been required. From the numerical analysis for the case of peritectically solidified Sm123, it was clarified that the constitutional supercooling must exist in the liquid when the 123 growth interface comes close to a 211 particle. It could also predict that larger 211 particle radius, smaller volume fraction of the 211 particles, larger growth rate, or smaller imposed temperature gradient cause easy occurrence of the constitutional supercooling. The growth rate and a 211 particle radius are determining parameters. Further consideration of the nucleation at the L/211 interface just ahead of the 123 growth front could describe the 123 growth morphological transition from the planar interface to the equiaxed blocky.

  7. Modelling ac ripple currents in HTS coated conductors

    NASA Astrophysics Data System (ADS)

    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

  8. Measurement Of Transverse Jc Profiles Of Coated Conductors Using A Magnetic Knife Of Permanent Magnets

    SciTech Connect

    Hanisch, J; Mueller, F M; Ashworth, S P; Coulter, J Y; Matias, Vlad

    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.

  9. Remarkable weakness against cleavage stress for YBCO-coated conductors and its effect on the YBCO coil performance

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Y.; Nakagome, H.; Takematsu, T.; Takao, T.; Sato, N.; Takahashi, M.; Maeda, H.

    2011-08-01

    Cleavage strength for an YBCO-coated conductor at 77 K was investigated with a model experiment. The nominal cleavage strength for an YBCO-coated conductor is extremely low, typically 0.5 MPa. This low nominal cleavage strength is due to stress concentration on a small part of the YBCO-coated conductor in cleavage fracture. Debonding by the cleavage stress occurs at the interface between the buffer layer and the Hastelloy substrate. The nominal cleavage strength for a slit edge of the conductor is 2.5-times lower than that for the original edge of the conductor; cracks and micro-peel existing over the slit edge reduce the cleavage strength for the slit edge. Cleavage stress and peel stress should be avoided in coil winding, as they easily delaminate the YBCO-coated conductor, resulting in substantial degradation of coil performance. These problems are especially important for epoxy impregnated YBCO-coated conductor coils. It appears that effect of cleavage stress and peel stress are mostly negligible for paraffin impregnated YBCO-coated conductor coils or dry wound YBCO-coated conductor coils.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Solution Fabrication of a Superconducting MgB2 Coated Conductor on Stainless Steel

    NASA Astrophysics Data System (ADS)

    Wang, Yin-Bo; Chen, Li-Ping; Zhang, Chen; Wang, Yue; Guo, Zheng-Shan; Chen, Yi-Ling; Feng, Qing-Rong; Gan, Zi-Zhao

    2012-04-01

    We report the solution fabrication of a MgB2 coated conductor on a stainless steel substrate. The precursor solution of Mg(BH4)2 diethyl ether is initially synthesized by refluxing the milled mixture of NaBH4 and MgCl2 in diethyl ether. Then the Mg(BH4)2 diethyl ether is spin coated on a stainless steel substrate and annealed in Mg vapor, which yields a homogeneous MgB2 coated conductor. X-ray diffraction indicates that the grown MgB2 coated conductor is polycrystalline. It has a superconducting transition temperature of 34-37 K. The slope of the upper critical field HC2 increases with decreasing temperature, and the extrapolated value of HC2(0) reaches ~28 T. The critical current density estimated by the Bean model is JC(25K, 0T)~106 A·cm-2. These parameters indicate that the solution method is potentially able to produce MgB2 coated conductors that can satisfy application purposes.

  12. Inkjet printing of multifilamentary YBCO for low AC loss coated conductors

    NASA Astrophysics Data System (ADS)

    Hopkins, S. C.; Joseph, D.; Mitchell-Williams, T. B.; Calleja, A.; Vlad, V. R.; Vilardell, M.; Ricart, S.; Granados, X.; Puig, T.; Obradors, X.; Usoskin, A.; Falter, M.; Bäcker, M.; Glowacki, B. A.

    2014-05-01

    Considerable progress has been made with the development of REBCO coated conductors in recent years, and high performance conductors are available commercially. For many applications, however, the cost remains prohibitive, and AC losses discourage their selection for higher frequency applications. Chemical solution deposition (CSD) methods are attractive for low-cost, scalable preparation of buffer and superconductor layers, and in many respects inkjet printing is the method of choice, permitting non-contact deposition with minimal materials wastage and excellent control of coating thickness. Highly textured coatings of YBCO and Gd-doped CeO2 have previously been reported on buffered metal substrates. Inkjet printing also introduces the possibility of patterning - directly depositing two and three dimensional structures without subtractive processing - offering a low-cost route to coated conductors with reduced AC losses. In this contribution, the inkjet deposition of superconducting YBCO tracks is reported on industrially relevant buffered metal substrates both by direct printing and an inverse patterning approach. In the latter approach, ceria tracks were printed reported, which are a candidate both for resistive filament spacers and buffer layers. TFA-based precursor solutions have been printed on SS/ABAD-YSZ/CeO2 and Ni-W/LZO/CeO2 RABiTS substrates, and the resulting multifilamentary samples characterised by microscopy and scanning Hall probe measurements. The prospects for future inkjet-printed low AC loss coated conductors are discussed, including control of interfilamentary resistivity and bridging, transposed filamentary structures and stabilisation material.

  13. AC loss reduction of TFA-MOD coated conductors in long length by laser scribing technique

    NASA Astrophysics Data System (ADS)

    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.

  14. HTS current lead units prepared by the TFA-MOD processed YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Shiohara, K.; Sakai, S.; Ishii, Y.; Yamada, Y.; Tachikawa, K.; Koizumi, T.; Aoki, Y.; Hasegawa, T.; Tamura, H.; Mito, T.

    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 1Ba 2Cu 3O 7-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 Hastelloy™ C-276 substrate tape with two buffer oxide layers of Gd 2Zr 2O 7 and CeO 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 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 ( I 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.

  15. Dissipated energy as a design parameter of coated conductors for their use in resistive fault current limiters

    NASA Astrophysics Data System (ADS)

    Schacherer, C.; Kudymow, A.; Noe, M.

    2008-02-01

    Coated conductors are suitable for many power applications like motors, magnets and superconducting fault current limiters (SCFCLs). For their use in resistive SCFCLs main requirements are quench stability and resistance development above Tc. Several coated conductors are available with different kinds of stabilization like thickness or material of cap-layer and additional stabilization. The stabilization can vary and has a great influence on the quench stability and quench behaviour of a coated conductor. Thus, for the dimensioning of a superconducting current limiting element there is a need of reliable and universal design parameters. This paper presents experimental quench test results on several coated conductor types with different stabilization and geometry. The test results show that the dissipated energy during a quench is a very useful parameter for the SCFCL design.

  16. YBCO coated conductors on highly textured Pd-buffered Ni-W tape

    NASA Astrophysics Data System (ADS)

    Celentano, G.; Galluzzi, V.; Mancini, A.; Rufoloni, A.; Vannozzi, A.; Augieri, A.; Petrisor, T.; Ciontea, L.; Gambardella, U.

    2006-06-01

    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 3°, 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.

  17. Apparatus and method for measuring critical current properties of a coated conductor

    DOEpatents

    Mueller, Fred M.; Haenisch, Jens

    2012-07-24

    The transverse critical-current uniformity in a superconducting tape was determined using a magnetic knife apparatus. A critical current I.sub.c distribution and transverse critical current density J.sub.c distribution in YBCO coated conductors was measured nondestructively with high resolution using a magnetic knife apparatus. 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 a sample of coated conductor. This reveals the critical current density distribution. A Fourier series inversion process was used to determine the transverse J.sub.c distribution in the sample.

  18. On-Line Texture Diagnostics for Coated Conductor Manufacture. Final Report

    SciTech Connect

    White, M. K.

    2002-12-30

    This Phase I project was undertaken to assess the feasibility of implementing a particular diagnostic method for characterizing the crystallographic texture of high temperature superconductor (HTS) coated conductors on-line during their reel-to-reel continuous manufacture. Key factors in this technique were the use of an area detector to greatly reduce scan time, an x-ray mirror to enhance incident beam brightness, and an automation scheme for diffractometer control, tape motion control, and calculation and output of texture characterizations.

  19. Coated conductor scale-up program at IGC-SuperPower

    NASA Astrophysics Data System (ADS)

    Selvamanickam, V.; Li, Y.; Sathiaraju, S.; Qiao, Y.; Zdun, K.; Hope, L.; Reeves, J.; Lenseth, K.; Haldar, P.

    2002-01-01

    The objective of the coated conductor program at IGC-SuperPower is to scale up substrate, buffer, and YBCO deposition process to manufacturing. Recently, pilot-scale manufacturing facilities were established for substrate, buffer, and YBCO preparation at IGC-SuperPower. High-quality substrate, buffer, and Y-Ba-Cu-O (YBCO) tapes are being produced in the pilot-scale facilities. .

  20. Measurement of transverse Jc profiles of coated conductors using a magnetic knife of permanent magnets

    SciTech Connect

    Haenisch, J; Mueller, F M; Ashworth, S P; Coulter, J Y; Matias, Vlad

    2008-01-01

    The transverse J{sub c} distribution in YBCO coated conductors was measured non-destructively 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 {micro}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.

  1. Nickel-copper alloy tapes as textured substrates for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Vannozzi, A.; Celentano, G.; Angrisani, A.; Augieri, A.; Ciontea, L.; Colantoni, I.; Galluzzi, V.; Gambardella, U.; Mancini, A.; Petrisor, T.; Rufoloni, A.; Thalmaier, G.

    2008-02-01

    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 ?-scan drops from about 9° of NiCuCo to 2° 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.

  2. Field and temperature scaling of the critical current density in commercial REBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Senatore, Carmine; Barth, Christian; 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 another. In the present work we have examined the critical surface for the current density, J c(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 fields of 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 = 0°, 45° and 90°, in order to probe the angular anisotropy of J c. In spite of the large variability of the CCs’ performance, we show here that field and temperature dependences of J c at a given angle can be reproduced over wide ranges using a scaling relation based only on three parameters. Furthermore, we present and validate a new approach combining magnetic and transport measurements for the determination of the scaling parameters with minimal experimental effort.

  3. Estimation of magnetic relaxation property for CVD processed YBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    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.

  4. Current status and prospects of national project on coated conductors in Japan

    NASA Astrophysics Data System (ADS)

    Shiohara, Y.; Yoshizumi, M.; Izumi, T.; Yamada, Y.

    2007-10-01

    Three years of the current 5-year national project since 2003 for development of coated conductors using Y-system superconductors have passed and lots of remarkable results have been achieved. In this paper, the current status and the future prospects of the national project are reviewed. The group of Fujikura Ltd. and SRL has worked on the long tape with high performance in the PLD-YBCO superconducting tapes on the IBAD-GZO buffered substrates. The highest Ic × L value of the tape is over 50 kAm, which consists of 212 m in length and 245 A of critical current (Ic). Additionally, a 500 m long IBAD-buffered tape with a reasonable in-plane texture was produced using a large scale IBAD apparatus by Fujikura. In the other group, long tape processings have been developed focusing on lowering its production cost. The extremely high Ic value of 735 A/cm-w was obtained in a short sample by the advanced TFA-MOD method on a CeO2(PLD)/GZO(IBAD)/Hastelloy substrate. In the efforts for the long tape processing, an 86 m long tape with an average Ic value of 300 A by a continuous reel-to-reel system and a 40 m long tape with 155 A by a batch system were realized. One hundred meter class long tapes were also obtained by the MOCVD and PLD-HoBCO processes. Both groups are aiming at the final goals of 500 m long tapes with a high Ic value of 300 A/cm-w by and of a production rate of 5 m/h. Furthermore, the feasibility studies for applications using coated conductors have already started according to the above mentioned success of long tape production. Multifilamentarization of coated conductors has been performed for AC loss reduction and it was practically confirmed that a tape with a narrower width results in smaller AC losses not only in short samples but also in a coil winding. Several kinds of coils using long coated conductors such as a solenoid and a pancake types and spiral shaped conductors for the cable were firstly made. Reasonable high performance results were confirmed

  5. Effect of self-field on the current distribution in Roebel-assembled coated conductor cables

    NASA Astrophysics Data System (ADS)

    Vojenčiak, M.; Grilli, F.; Terzieva, S.; Goldacker, W.; Kováčová, M.; Kling, A.

    2011-09-01

    Roebel cables are a promising solution for high current, low AC loss cables made of high-temperature superconductors in the form of coated conductors. High current creates significant self-field, which influences the superconductor's current-carrying capability. In this paper, we investigate the influence of the self-field on the cable's critical current and the current repartition among the different strands. In order to investigate the cable's critical current, we analysed the influence of flux creep on the cable properties. Using the experimental material's properties derived from measurements on a single conductor as input for our calculations, we were able to predict the critical current of the cable in two limiting situations: good current sharing and complete electrical insulation among the strands. The results of our calculations show good agreement with the measured critical current of three Roebel cable samples.

  6. Design of a Cosine-theta Dipole Magnet Wound with Coated Conductors Considering their Deformation at Coil ends During Winding Process

    NASA Astrophysics Data System (ADS)

    Amemiya, Naoyuki; Miyahara, Hidetoshi; Ogitsu, Toru; Kurusu, Tsutomu

    By using differential geometry, we modeled the three-dimensional shapes of the coil ends of cosine-theta magnets while considering local edge-wise bend, local flat-wise bend, and torsion of coated conductors. We focus on the feasibility of winding coil ends against the stress caused by bending. We discussed the feasibility of winding based on two assumptions to form coil ends: all turns of coated conductors are free from edge-wise bend; faces of all turns of coated conductors are completely parallel. Using the first assumption, we designed a cosine-theta dipole magnet wound with coated conductors.

  7. Mixed Electronic and Ionic Conductor-Coated Cathode Material for High-Voltage Lithium Ion Battery.

    PubMed

    Shim, Jae-Hyun; Han, Jung-Min; Lee, Joon-Hyung; Lee, Sanghun

    2016-05-18

    A lithium ionic conductor, Li1.3Al0.3Ti1.7(PO4)3 (LATP), is introduced as a coating material on the surface of Mg-doped LiCoO2 to improve electrochemical performances for high-voltage (4.5 V) lithium ion batteries. Structure, morphology, elemental distribution, and electrical properties of the materials are thoroughly characterized by SEM, TEM, EELS, EDS, and C-AFM. The coating layer is electrically conductive with the aid of Mg ions which are used as a dopant for the active materials; therefore, this mixed electronic ionic conductor strongly enhances the electrochemical performances of initial capacity, cycling property, and rate capability. The LATP coating layer also demonstrates very promising applicability for 4.4 V prismatic full cells with graphite anode, which correspond to the 4.5 V half-cells with lithium anode. The 2900 mA h full cells show 85% of capacity retention after 500 cycles and more than 60% after 700 cycles.

  8. Mixed Electronic and Ionic Conductor-Coated Cathode Material for High-Voltage Lithium Ion Battery.

    PubMed

    Shim, Jae-Hyun; Han, Jung-Min; Lee, Joon-Hyung; Lee, Sanghun

    2016-05-18

    A lithium ionic conductor, Li1.3Al0.3Ti1.7(PO4)3 (LATP), is introduced as a coating material on the surface of Mg-doped LiCoO2 to improve electrochemical performances for high-voltage (4.5 V) lithium ion batteries. Structure, morphology, elemental distribution, and electrical properties of the materials are thoroughly characterized by SEM, TEM, EELS, EDS, and C-AFM. The coating layer is electrically conductive with the aid of Mg ions which are used as a dopant for the active materials; therefore, this mixed electronic ionic conductor strongly enhances the electrochemical performances of initial capacity, cycling property, and rate capability. The LATP coating layer also demonstrates very promising applicability for 4.4 V prismatic full cells with graphite anode, which correspond to the 4.5 V half-cells with lithium anode. The 2900 mA h full cells show 85% of capacity retention after 500 cycles and more than 60% after 700 cycles. PMID:27127906

  9. Achievements in M-PACC Project and Future Prospects on R&D of Coated Conductors in Japan

    NASA Astrophysics Data System (ADS)

    Izumi, Teruo

    A national project of Materials & Power Applications of Coated Conductors (M-PACC) including R&D of coated conductors (CC) and the applications in Japan had been promoted for 5years and was finished at the end of February in 2013. In the R&D of coated conductors, the necessary specifications required from the applications were set as the targets and all of them were successfully achieved. Through the development, there were lots of remarkable results had been obtained, such as high in field Ic value of 54A/cm-width at 77K under 3T in 200m long tape, one-tenth of AC loss reduction in 100m long tape with 10 filaments etc. Although these achievements could make the lots of applications of coated conductors realize, further improvement is needed to obtain an absolute advantages to competitive technologies. Based on this situation, the development should be continued to have the coated conductors with much higher specifications, which is called as 3rd generation wire.

  10. Growth of graphene on cylindrical copper conductors as an anticorrosion coating: a microscopic study

    NASA Astrophysics Data System (ADS)

    Datta, A. J.; Gupta, B.; Shafiei, M.; Taylor, R.; Motta, N.

    2016-07-01

    We have successfully grown graphene film on the surface of cylindrical copper conductors by chemical vapour deposition. The quality and number of graphene layers have been investigated using Raman spectroscopy, Raman mapping and scanning electron microscopy, as a function of methane gas flow rate and of growth temperature. Transmission electron microscopy analysis has been performed to verify the number of graphene layers, confirming the results obtained by Raman spectroscopy. The results open up the possibility of using graphene as an anticorrosion coating for copper cables and earth grids.

  11. Development of Coated Conductors in Japanese National Project "Development of Fundamental Technologies for HTS Coils"

    NASA Astrophysics Data System (ADS)

    Yoshizumi, Masateru; Izumi, Teruo; Shiohara, Yuh

    RE1Ba2Cu3O7-x (REBCO, RE=rare earth) coated conductors have attracted the attention of many scientists due to the high superconducting properties, etc. Due to the great progress of R&D on coated conductors, the activities have shifted to specific applications. The new Japanese national project, named as "Development of Fundamental Technologies for HTS Coils", started last year aiming for the applications of MRI and medical accelerators. To meet the requirements of those applications, the R&D of REBCO coated conductors (CCs) are being performed with that of coiling technology in parallel. The theme has two sub-themes of "development of long CCs with high in-field performance" and "development of CCs with extremely low heat generation" in this national project. The ambitious goals of these themes are set as intermediate ones due 2016 Mar; the theme of in-field: 100m-500A/cm-w@65K, 3T -850A/cm-w@35K, 10T, the theme of low heat generation: 100m-500 μm of filament width w/ Icfilament inhomogeneity of distribution within 10% and joint resistance below 5nΩ. The final goals of these themes due 2018 Mar. were set as follows; the theme of in-field: 200m-600A/cm-w@65K, 3T -1000A/cm-w@35K, 10T, the theme of low heat generation: 200m-500 μm of filament width w/ Icfilament distribution within 5% and joint resistance below 3nΩ. The objectives, goals and progress of this project will be reviewed in this article. As for the progress, for example, the combination of EuBCO+BHO was found to be effective to improve the in-field performance of PLD derived coated conductors. A 94 m long wire with Icmin of 108A/cm-w@77K, 3T (corresponding to 472A/cm-w @65K, 3T) was successfully fabricated. It is as twice Icmin of the long tape as the highest one in the previous project.

  12. High current density electropolishing in the preparation of highly smooth substrate tapes for coated conductors

    DOEpatents

    Kreiskott, Sascha; Matias, Vladimir; Arendt, Paul N.; Foltyn, Stephen R.; Bronisz, Lawrence E.

    2009-03-31

    A continuous process of forming a highly smooth surface on a metallic tape by passing a metallic tape having an initial roughness through an acid bath contained within a polishing section of an electropolishing unit over a pre-selected period of time, and, passing a mean surface current density of at least 0.18 amperes per square centimeter through the metallic tape during the period of time the metallic tape is in the acid bath whereby the roughness of the metallic tape is reduced. Such a highly smooth metallic tape can serve as a base substrate in subsequent formation of a superconductive coated conductor.

  13. Modeling the Critical Current Decrease in Coated Conductors with Film Thickness

    SciTech Connect

    D. Agassi; D.K. Christen; S.J. Pennycook

    2007-01-01

    YBCO-based Coated Conductors (CC) are touted as the next generation of high current=carrying capacity High Temperature Superconductors (HTS) wires. If commercially viable, CC will signal a revolution in power trnasmission, with enormous economic consequences. It has been recently reported that the observed ciritical current in such CC is decreasing with the fil thickness d, roughly as d-1/2. The origin of this decrease is not understood. This work is aimed at developing a simple model to explain this feature.

  14. Influence of superconductor film composition on adhesion strength of coated conductors

    SciTech Connect

    Kesgin, Ibrahim; Khatri, Narayan; Liu, Yuhao; Delgado, Louis; Galstyan, Eduard; Selvamanickam, Venkat

    2015-11-20

    The effect of high temperature superconductor (HTS) film composition on the adhesion strength of rare- earth barium copper oxide coated conductors (CCs) has been studied. It has been found that the mechanical integrity of the superconductor layer is very susceptible to the defects especially those along the ab plane, probably due to the weak interfaces between the defects and the matrix. Gd and Y in the standard composition were substituted with Sm and the number of in-plane defects was drastically reduced. Consequently, a four-fold increase in adhesion or peeling strength in Sm-based CCs was achieved compared to the standard GdYBCO samples.

  15. Insert Coil Test for HEP High Field Magnets Using YBCO Coated Conductor Tapes

    SciTech Connect

    Lombardo, V.; Barzi, E.; Turrioni, D.; Zlobin, A.V.; /Fermilab

    2011-06-15

    The final beam cooling stages of a Muon Collider may require DC solenoid magnets with magnetic fields of 30-50 T. In this paper we present progress in insert coil development using commercially available YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} Coated Conductor. Technological aspects covered in the development, including coil geometry, insulation, manufacturing process and testing are summarized and discussed. Test results of double pancake coils operated in liquid nitrogen and liquid helium are presented and compared with the performance of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} tape short samples.

  16. Thermal stability of YBCO coated conductor with different Cu stabilizer thickness

    NASA Astrophysics Data System (ADS)

    Bae, J. H.; Park, H. Y.; Eom, B. Y.; Seong, K. C.; Baik, S. K.

    2010-11-01

    The studies on the conduction-cooled superconducting magnets are actively underway with rapid advancement in refrigeration technology recently. YBCO coated conductor (CC) is one of the promising conductors for a conduction-cooled superconducting magnet because of increasing the operation temperature of magnets and being able to have cost collectiveness with conventional copper conductor in the future. However, it is known that quench propagation velocity in high-temperature superconductor (HTS) is two or three orders of magnitude slower than that in low-temperature superconductor because of its large heat capacity and the high operating temperature. The hot spot will emerge in local region if a critical current is non-uniform along the length of HTS tape and eventually, it causes permanent destroy for the whole HTS tape. Based on the protection of YBCO CC, it is necessary to determine a suitable stabilizer thickness for YBCO CC so that the temperature of hot spot in local area does not exceed the permissible temperature. In this study, we have established a suitable thermal analysis model, and analyzed minimum quench energy and thermal properties for three kinds of YBCO CC samples with different stabilizer thickness, which are fabricated by Superpower Incorporated, using finite element method.

  17. Magnetization ac loss reduction in HTS CORC® cables made of striated coated conductors

    NASA Astrophysics Data System (ADS)

    Vojenčiak, M.; Kario, A.; Ringsdorf, B.; Nast, R.; van der Laan, D. C.; Scheiter, J.; Jung, A.; Runtsch, B.; Gömöry, F.; Goldacker, W.

    2015-10-01

    High temperature superconductors (HTSs), like for instance REBCO (RE = rare earth) coated conductors, are of high potential for building large superconducting magnets. Some magnets, such as accelerator magnets, require the use of superconducting cables to allow fast ramping, and low magnetization loss to mitigate field quality issues. One of the methods to lower ac loss is to divide the superconducting layer in the tape into filaments. In this paper, conductors with copper stabilization for practical applications are laser scribed into narrow filaments. Striated tapes are then wound into conductor on round core (CORC®) cables. The critical current and magnetization ac loss of single tapes were measured. We found that the stabilizing copper layer causes difficulties for laser scribing. The degradation of the critical current is more pronounced than in the case of non-stabilized tapes. The selection of the number of filaments is therefore a compromise between critical current degradation and reduction of ac loss. Based on the results obtained from single tape experiments, the optimum number of filaments in 4 mm wide tapes was chosen, and CORC® cables with 2, 3 and 4 layers of tapes with and without filaments were manufactured. Magnetization ac loss measurements at 77 K showed a reduction of ac loss in the cables with filaments. This reduction corresponds almost to the number of filaments. Measurement at different frequencies also showed that the coupling loss in CORC® cables with a short twist-pitch is relatively small in comparison to hysteretic loss.

  18. How filaments can reduce AC losses in HTS coated conductors: a review

    NASA Astrophysics Data System (ADS)

    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. How filaments can reduce AC losses in HTS coated conductors: a review

    NASA Astrophysics Data System (ADS)

    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.

  20. Coated conductors

    DOEpatents

    Arendt, Paul N.; Foltyn, Stephen R.; Stan, Liliana; Usov, Igor O.; Wang, Haiyan

    2010-06-15

    Articles are provided including a base substrate having a layer of an IBAD oriented material thereon, and, a layer of barium-containing material selected from the group consisting of barium zirconate, barium hafnate, barium titanate, barium strontium titanate, barium dysprosium zirconate, barium neodymium zirconate and barium samarium zirconate, or a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the layer of an IBAD oriented material. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of barium-containing material selected from the group consisting of barium zirconate, barium hafnate, barium titanate, barium strontium titanate, barium dysprosium zirconate, barium neodymium zirconate and barium samarium zirconate, or a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates.

  1. Nonvacuum Deposition of Silver Doped YBCO Coated Conductor on %100 Lattice Match Buffered Ni Tapes

    NASA Astrophysics Data System (ADS)

    Arda, L.; Cakiroglu, O.; Keskin, S.; Sacli, O. A.

    2007-04-01

    Silver doped YBa2Cu3O7-δ (YBCO) coated conductors were fabricated on Gd1.624Ho0.376O3 (100 % lattice match with YBCO) textured buffer layers on Ni tape by reel-to-reel sol-gel dip coating system. Sample were prepared with different wt(1-5) % Ag doped ratio. The surface morphologies and microstructure of all sample were characterized by ESEM, EDS and XRD. Pole figure texture analyses have been done to characterize texture of buffer layer and YBCO superconducting film . The critical current Ic measurement was performed using four wire method with the 1 μV/cm criterion. The critical current density, Jc was measured to be 2.2 × 104 A/cm2 at 77 K self field for 1 wt % Ag doped YBCO sample.

  2. Life cycle cost study for coated conductor manufacture by electron beam and pulsed laser deposition systems

    SciTech Connect

    Chapman, J.N.

    1999-04-14

    The results of this study establish a framework for evaluation of the cost impact of many performance parameters in coated conductor manufacturing systems. Since the cost and concepts are based on early developmental results and engineering judgment, the study should be updated periodically based on latest data to enhance its usefulness. The study should be expanded to include other promising processes under consideration or development for manufacture of coated conductors. Review of this study by as wide a group of experts from industry, national laboratories and universities as possible is desirable to facilitate improving accuracy of the estimates and communication on the issues involved. The results for the case of achieving the $10/kA-m goal at a J{sub c} of 10{sup 5} a/cm{sup 2} applicable to applications requiring a magnetic field perpendicular to the direction of current flow may be viewed as somewhat discouraging. However, there is ample margin for improvement due to continued development and engineering that could enable meeting the goal of $10/kA-m.

  3. Inhomogeneity effects in HTS coated conductors used as resistive FCLs in medium voltage grids

    NASA Astrophysics Data System (ADS)

    Colangelo, Daniele; Dutoit, Bertrand

    2012-09-01

    For resistive fault current limiters (RFCLs) based on high temperature superconducting coated conductors (HTS-CCs), inhomogeneity, in terms of critical current and geometrical imperfections such as stabilizer and substrate thicknesses, plays a very important role and it may limit the penetration of such devices into the electrical market. This paper presents an electrothermal model, developed in SimPowerSystem™, able to describe the transient response of HTS-CC candidates with different degrees of inhomogeneity, both in terms of critical current and of stabilizer thickness. Critical current inhomogeneity has been modeled with Gaussian distributions. The layer thicknesses used in the simulations have been chosen by fitting the temperature dependence of real tape resistances. Our approach considers relative inhomogeneity positions as well as thermal conduction along the HTS-CC length. The model is tuned using experimental measurements made on ReBaCuO coated conductors. A new dynamical thermal calibration of the model is proposed using finite element method calculations. Inhomegeneity effects with different possible faults (e.g. three phase and single phase short-circuit) are presented.

  4. Doubling of the Critical Current Density of 2G-YBCO Coated Conductors through proton irradiation

    NASA Astrophysics Data System (ADS)

    Welp, Ulrich; Jia, Ying; Kwok, Wai-Kwong; Rupich, Marty; Fleshler, Steven; Kayani, Asfghar

    2013-03-01

    We report on magnetization and transport measurements of the critical current density of commercial 2G YBCO coated conductors before and after proton irradiation. The samples were irradiated along the c-axis with 4 MeV protons to a fluence of 1.5x1016 p/cm2. We find that at temperatures below 50 K, proton irradiation increases Jc by a factor of 2 in low fields and increases up to 2.5 in fields of 7 T. At 77 K, proton irradiation is less effective in enhancing the critical current. Doubling of Jc in fields of several Tesla and at temperatures below 50 K will be highly beneficial for applications of coated conductors in rotating machinery, generators and magnet coils. - Work supported by the US DoE-BES funded Energy Frontier Research Center (YJ), and by Department of Energy, Office of Science, Office of Basic Energy Sciences (UW, WKK), under Contract No. DE-AC02-06CH11357.

  5. Flux pinning study of RE barium coper oxide coated conductors for high field magnet applications

    NASA Astrophysics Data System (ADS)

    Xu, Aixia

    REBa2Cu3O7-δ (REBCO, RE = rare earth) coated conductor (CC) holds great promise for high field magnet applications owing to its strong irreversibility field (Hirr), low electromagnetic anisotropy (γ2), and high critical current density (Jc). The work of this thesis is tightly related to the development of the funded 32 T, all-superconducting magnet project at the NHMFL. My concern is thus for understanding the optimizing of the working parameters of REBCO CC at low temperatures T, and very high magnetic fields H, focusing on how to enhance Ic and to reduce its angular dependence. Increasing the active cross-section is a direct and economical strategy to enhance the current-carrying capability for REBCO coated conductors. Unfortunately, the high Jc in thin REBCO layers is seldom sustained in thick layers because of difficulties of thick film growth control. In the presence of strong 3D (pin separation far less than film thickness) pins, a high and thickness-independent (Jc) should result. One of major tasks of this thesis is to explore what are the effective strong 3D pins that develop a high and thickness-independent Jc. High and weak thickness-dependent Jc at 77 K is obtained on most recent coated conductors, and BZO nanorods and RE2O 3 nanoparticles are identified as strong 3D pins contributing to this respectable Jc performance. At 77 K, we found that the strong pinning of BZO nanorods remains at least up to 9 T, whereas the strong pinning of RE2O3 nanoparticles gradually evolves to weak collective pinning as the irreversibility field is approached. The second principal part of this thesis concentrates on understanding and minimizing the angular dependence of Jc. Our study is based on the following procedure. First, we investigated the angular dependence of Jc (Jc(θ)) in the working condition of the future 32 T all-superconducting magnet, i.e. 4.2 K and high magnetic field up to 31 T. Our work shows that the low temperature Jc(θ) is Ginzburg-Landau-like at

  6. Ac-loss measurement of a DyBCO-Roebel assembled coated conductor cable (RACC)

    NASA Astrophysics Data System (ADS)

    Schuller, S.; Goldacker, W.; Kling, A.; Krempasky, L.; Schmidt, C.

    2007-10-01

    Low ac-loss HTS cables for transport currents well above 1 kA are required for application in transformers and generators and are taken into consideration for future generations of fusion reactor coils. Coated conductors (CC) are suitable candidates for high field application at an operation temperature around 50-77 K, which is a crucial precondition for economical cooling costs. We prepared a short length of a Roebel bar cable made of industrial DyBCO coated conductor (Theva Company, Germany). Meander shaped tapes of 4 mm width with a twist pitch of 122 mm were cut from 10 mm wide CC tapes using a specially designed tool. Eleven of these strands were assembled to a cable. The electrical and mechanical connection of the tapes was achieved using a silver powder filled conductive epoxy resin. Ac-losses of a short sample in an external ac field were measured as a function of frequency and field amplitude in transverse and parallel field orientations. In addition, the coupling current time constant of the sample was directly measured.

  7. Superconducting layer thickness dependence of magnetic relaxation property in CVD processed YGdBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Takahashi, Y.; Kiuchi, M.; Otabe, E. S.; Matsushita, T.; Shikimachi, K.; Watanabe, T.; Kashima, N.; Nagaya, S.

    2011-11-01

    One of the most important properties of coated conductors for Superconducting Magnetic Energy Storage (SMES) is the relaxation property of persistent superconducting current. This property can be quantitatively characterized by the apparent pinning potential U0∗. In this paper, the dependence of U0∗ on the thickness of superconducting layer d is investigated in the range of 0.33-1.43 μm at the temperature range of 20-30 K and in magnetic fields up to 6.5 T for Y 0.7Gd 0.3Ba 2Cu 3O 7- δ coated conductors. It was found that the value of critical current density did not appreciably depend on d at 20 K. This indicates that no structural deterioration of superconducting layer occurs during the process of increasing thickness. U0∗ increases and then tends to decrease with an increasing magnetic field. The magnetic field at which U0∗ starts to decrease increases with increasing thickness. This property was analyzed using the flux creep-flow model. Application of scaling law is examined for the dependence of U0∗ on magnetic field and temperature. It was found that the dependence could be expressed using scaling parameters B,U0 peak∗ in the temperature range 20-30 K.

  8. Calculating AC Losses in High-temperature Superconducting Cables Comprising Coated Conductors

    NASA Astrophysics Data System (ADS)

    Noji, Hideki; Kawano, Shouta; Akaki, Yoji; Hamada, Tsugio

    In this study, we present a new calculation model of AC loss in a high-temperature superconducting (HTS) cable comprising coated conductors. AC loss is calculated by an electric circuit (EC) model. A previous EC model had three circuit elements: resistance as a function of the layer current, inductances related to the circumferential and axial fields. The new EC model has only inductances, and resistance is eliminated. In both models, AC loss of the coated conductor in each layer of an HTS cable is calculated on the basis of the Norris equation for a thin strip. The differences between measurement and calculations using the previous and new models are 12% and 14%, respectively, when transporting 1 kArms, which indicates that the new model is applicable for the calculation of AC loss in an HTS cable. These results indicate that layer current is dependent on inductances and not on resistance. The elimination of resistance simplifies AC loss calculation because it does not require repeated calculations for the convergence of the layer current. The calculation time was 1/20th of that of the previous model. In the new model, the Norris equation can be replaced with the calculation result obtained by the two-dimensional finite element method to obtain more accurate AC loss.

  9. Inter- and intragrain transport measurements in YBa2Cu3O7Àx deformation textured coated conductors

    SciTech Connect

    Feldmann, D.M.

    2010-12-10

    Using photolithography, links for transport measurement have been placed across individual Ni grain boundaries and within individual Ni grains on several coated conductor samples. The typical Ni grain size is ;50 mm, while the YBa2Cu3O72x grains are submicron in size. It is found that the intragrain Jc(0 T,77 K) can exceed 5 MA/cm2, thus showing that present coated conductor Jc values are not significantly limited by the intragrain Jc . Inter- and intragrain Jc values ranged from one-half to more than four times full-width measured values, demonstrating that current percolates through the conductor. The misorientation angle dependence of Jc fits well with previous studies of @001# tilt SrTiO3 bicrystals.

  10. VOLTAGE DISTRIBUTION AND MECHANICAL STRENGTH IN SPLICE JOINTS MADE FROM AS-MANUFACTURED YBCO COATED CONDUCTORS

    SciTech Connect

    Duckworth, Robert C; Zhang, Yifei; Gouge, Michael J; Rey, Christopher M; Van der Laan, Danko; Clickner, Cam

    2010-01-01

    With recommendations from wire manufacturers as a starting point, a series of solder joints were fabricated and characterized to determine the best method to produce repeatable, low-resistance and high-mechanical-strength splices in as-manufactured, stabilized YBCO coated conductors. From the 2.54 cm long splice joints that were fabricated, parameters such as solder material, stabilization material, fabrication method, and conductor geometry were varied to determine the impact of each on splice joint properties. Results indicate that the lowest resistance splice joints were influenced primarily by the tape orientation in the joint and the stabilization material. The lowest resistances were between 2 10-8 and 1.0 10-7 in 4-mm wide tapes and were obtained from pure copper stabilized tapes oriented with the YBCO layers in closest proximity. The voltage drop along the splice length indicated that only a fraction of the splice length contributes to the splice joint resistance. Mechanical characterization of splice joints showed that the joint resistance remained unchanged under axial stress up to a stress level at which the critical current of the tapes forming the joint degrades irreversibly.

  11. High-rate reel-to-reel continuous coating of biaxially textured magnesium oxide thin films for coated conductors

    SciTech Connect

    Chudzik, M. P.; Erck, R. A.; Balachandran, U.; Luo, Z. P.; Miller, D. J.; Kannewurf, C. R.

    2000-01-12

    Biaxially textured thin films of magnesium oxide (MgO) were deposited by electron beam evaporation at deposition rates of 0.6 {mu}m/min on moving Ni-based alloy tapes as oriented buffer layers for coated conductors. Moving substrates were inclined with respect to the atomic vapor and translated through collimated dual vapor sources. Growth anisotropy in the MgO and self-shadowing effects due to the inclined angle combine to create biaxial texture in the deposited thin films. MgO films grown to a thickness of 2.0 {mu}m with this inclined-substrate deposition technique have yielded in-plane textures of 10--12{degree} fill-width half-maximum (FWHM). Results of a parametric study on the in-plane texture in short-length static-mode samples are presented, along with preliminary results of long-length samples deposited under translating conditions.

  12. Factors associated with biaxial texturing of Cu tapes for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Kim, Y. H.; Sung, T. H.; Han, S. C.; Han, Y. H.; Jeong, N. H.; Kim, C. J.; Jun, B. H.; Oh, S. S.; Kim, H. S.; Kim, T. H.; No, K. S.

    2007-10-01

    A biaxially textured Cu(2 0 0) tape was used as a substrate for YBCO coated conductors by cold rolling followed by recrystallization heat treatment. In this work, we studied the influence of annealing conditions and final tape thickness on the recrystallization process. Phi (ϕ) scan and omega (ω) scan XRD revealed that the best in-plane and out-of-plane alignment of the Cu tape (thickness 100 μm), measured in terms of full width half maximum (FWHM) values of 6.64° and 4.49°, were obtained by annealing at 800 °C for 30 min. The texture of CeO2 buffer layer thermally-evaporated on the Cu tape was also analyzed.

  13. Critical current density measurement of striated multifilament-coated conductors using a scanning Hall probe microscope

    NASA Astrophysics Data System (ADS)

    Li, Xiao-Fen; Kochat, Mehdi; Majkic, Goran; Selvamanickam, Venkat

    2016-08-01

    In this paper the authors succeeded in measuring the critical current density ({J}{{c}}) of multifilament-coated conductors (CCs) with thin filaments as low as 0.25 mm using the scanning hall probe microscope (SHPM) technique. A new iterative method of data analysis is developed to make the calculation of {J}{{c}} for thin filaments possible, even without a very small scan distance. The authors also discussed in detail the advantage and limitation of the iterative method using both simulation and experiment results. The results of the new method correspond well with the traditional fast Fourier transform method where this is still applicable. However, the new method is applicable for the filamentized CCs in much wider measurement conditions such as with thin filament and a large scan distance, thus overcoming the barrier for application of the SHPM technique on {J}{{c}} measurement of long filamentized CCs with narrow filaments.

  14. Evaluation of Transverse Tensile Stress Characteristics of GdBCO Coated Conductors

    NASA Astrophysics Data System (ADS)

    Sato, H.; Nakamura, N.; Fujita, S.; Daibo, M.; Iijima, Y.

    Recently, GdBCO coated conductor (CC) coils for high field magnets are investigated for practical use. GdBCO CC coils are subjected to longitudinal and transverse tensile stresses in their operation, so there is some research for mechanical properties of the GdBCO CCs in the recent years. Fujikura has also researched mechanical properties, for example, tensile or delamination strength, of the GdBCO CCs. In this report, we investigated pin-pull delamination test in Liquid nitrogen (LN2) to research mechanical delamination and critical current (Ic) degradation strength. We found out mechanical delamination strength is corresponding to Ic degradation strength. In addition, we experiment repeated transverse tensile stress on GdBCO CCs in LN2, most of the samples have more than 50 times at 50 MPa, which corresponds to single delamination strength, and there is no Ic degradation before mechanical delamination.

  15. Mechanical and transport properties of IBAD/EDDC-SmBCO coated conductor tapes during fatigue loading

    NASA Astrophysics Data System (ADS)

    Shin, Hyung-Seop; Dedicatoria, Marlon J.

    2011-06-01

    In electrical devices like superconducting motor, generator and SMES, HTS coated conductor (CC) tapes will be subjected to alternating stress or strain during manufacturing and operation. The repeated loading will affect the mechanical integrity and eventually the electrical transport property of CC tapes. Therefore in such applications, electro-mechanical property of CC tapes should be evaluated. In this study, the endurance of an IBAD/EDDC-SmBCO CC tape under high-cycle fatigue loading has been evaluated. Applied maximum stress and fatigue life ( S-N) relation was obtained at 77 K. The mechanical properties and the critical current, I c, of the sample under fatigue loading were investigated at 77 K. Considering the practical operating environment, the effect of the stress ratio R, on the degradation behavior of I c under fatigue loading was also examined.

  16. Pd layer on cube-textured substrates for MOD-TFA and PLD YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Mancini, A.; Celentano, G.; Galluzzi, V.; Rufoloni, A.; Vannozzi, A.; Augieri, A.; Ciontea, L.; Petrisor, T.; Gambardella, U.; Longo, G.; Cricenti, A.

    2008-01-01

    Pd films were deposited on rolling assisted biaxially textured substrate (RABiTS) Ni-5 at.% W in order to exploit the Pd effect of the texture sharpening with respect to that of the substrate, for the development of YBa2Cu3O7-x (YBCO) coated conductors. The Pd sharpening effect was relevant in the out-of-plane direction where the reduction for the ω-scans' full width at half maximum (FWHM) ranged from 55 to 65%, depending on the substrate roughness. The obtained minimum values of the FWHM in the transverse rolling direction of the (002) Pd ω-scan and in the (111) Pd phi-scan were of about 2.5° and 5°, respectively. The CeO2/YSZ/CeO2 (YSZ is Y2O3-stabilised ZrO2) heterostructure of the buffer layer was developed by pulsed laser deposition (PLD). In order to transfer the sharp orientation of the Pd film, both the seed CeO2 layer and the YSZ layer were deposited at low temperatures (450 °C), low enough to avoid Pd/Ni-W interdiffusion. The YBCO, films deposited by both PLD and metal-organic deposition (MOD) using metal trifluoroacetate acid (TFA), exhibited rolling direction (005) ω-scan and the (113) phi-scan FWHM values of about 2° and 5°, respectively. In spite of the complete interdiffusion between Ni and Pd during the YBCO film deposition, the coated conductors exhibit good adherence, as well as a smooth and crack-free surface. A zero-resistance critical temperature (TC0) of 90.8 K for the MOD-TFA YBCO films and critical current-density (JC) up to 2.2 MA cm-2 at 77 K and self-field for PLD YBCO films have been obtained.

  17. Development of Solution Buffer Layers for RABiTS Based YBCO Coated Conductors

    SciTech Connect

    Paranthaman, Mariappan Parans; Qiu, Xiaofeng; Kim, Kyunghoon; Shi, D.; Zhang, Yifei; Li, Xiaoping; Sathyamurthy, Srivatsan; Thieme, C. L. H.; Rupich, M. W.

    2010-01-01

    The main objective of this research is to find a suitable alternate solution based seed layer for the standard RABiTS three-layer architecture of physical vapor deposited CeO2 cap/YSZ barrier/Y2O3 seed on Ni-5%W metal tape. In the present work, we have identified CeO2 buffer layer as a potential replacement for Y2O3 seeds. Using a metal-organic deposition (MOD) process, we have grown smooth, crack-free, epitaxial thin films of CeO2 (both pure and Zr, Cu and Gd-doped) directly on biaxially textured Ni-5W substrates in short lengths. Detailed XRD studies indicate that a single epitaxial CeO2 phase with slightly improved out-of-plane texture compared to the texture of underlying Ni-W substrates can be achieved in pure, undoped CeO2 samples. We have also demonstrated the growth of YSZ barrier layers on pure CeO2 seeds using sputtering. Both sputtered CeO2 cap layers and MOD-YBCO films were grown epitaxially on these YSZ-buffered MOD-CeO2/Ni-5W substrates. High critical currents per unit width, Ic of 264 A/cm (critical current density, Jc of 3.3 MA/cm2) at 77 K and 0.01 T was achieved for 0.8 m thick MOD-YBCO films grown on MOD-CeO2 seeds. These results indicate that CeO2 films can be grown directly on Ni-5W substrates and still support high performance YBCO coated conductors. This work holds promise for a route for producing low-cost buffer architecture for RABiTS based YBCO coated conductors.

  18. Development of Solution Buffer Layers for RABiTS Based YBCO Coated Conductors

    SciTech Connect

    Paranthaman, Mariappan Parans; Qiu, Xiaofeng; List III, Frederick Alyious; Zhang, Yifei; Li, Xiaoping; Sathyamurthy, Srivatsan; Thieme, C. L. H.; Rupich, M. W.

    2011-01-01

    Abstract The main objective of this research is to find a suitable alternate solution based seed layer for the standard RABiTS three-layer architecture of physical vapor deposited CeO cap/YSZ barrier/Y O seed on Ni-5%W metal tape. In the present work, we have identified CeO buffer layer as a potential replacement for Y O seeds. Using a metal-organic deposition (MOD) process, we have grown smooth, crack-free, epitaxial thin films of CeO (pure and Zr, Cu and Gd-doped) directly on biaxially textured Ni-5W substrates in short lengths. Detailed XRD studies indicate that a single epitaxial CeO phase with slightly improved out-of-plane texture compared to the texture of the underlying Ni-W substrates can be achieved in pure, undoped CeO samples. We have also demonstrated the growth of YSZ barrier layers on pure CeO seeds using sputtering. Both sputtered CeO cap layers and MOD-YBCO films were grown epitaxially on these YSZ-buffered MOD-CeO /Ni-5W substrates. High critical currents per unit width, of 264 A/cm (critical current density, of 3.3 MA/cm ) at 77 K and 0.01 T was achieved for 0.8 m thick MOD-YBCO films grown on MOD-CeO seeds. These results indicate that CeO films can be grown directly on Ni-5W substrates and still support high performance YBCO coated conductors. This work holds promise for a route for producing low-cost buffer architecture for RABiTS based YBCO coated conductors.

  19. Modified Lanthanum Zirconium Oxide buffer layers for low-cost, high performance YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Parans Paranthaman, M.; Sathyamurthy, S.; Li, Xiaoping; Specht, E. D.; Wee, S. H.; Cantoni, C.; Goyal, A.; Rupich, M. W.

    2010-03-01

    The pyrochlore Lanthanum Zirconium Oxide, La 2Zr 2O 7 (LZO), has been developed as a potential replacement barrier layer in the standard RABiTS three-layer architecture of physical vapor deposited CeO 2 cap/YSZ barrier/Y 2O 3 seed on Ni-5%W metal tape. The main focus of this research is to ascertain whether: (i) we can further improve the barrier properties of LZO; (ii) we can modify the LZO cation ratio and still achieve a high level of performance; and (iii) it is possible to reduce the number of buffer layers. We report a systematic investigation of the LZO film growth with varying compositions of La:Zr ratio in the La 2O 3-ZrO 2 system. Using a metal-organic deposition (MOD) process, we have grown smooth, crack-free, epitaxial thin films of La xZr 1-xO y ( x = 0.2-0.6) on standard Y 2O 3 buffered Ni-5W substrates in short lengths. Detailed XRD studies indicate that a single epitaxial LZO phase with only (0 0 1) texture can be achieved in a broad compositional range of x = 0.2-0.6 in La xZr 1-xO y. Both CeO 2 cap layers and MOD-YBCO films were grown epitaxially on these modified LZO barriers. High critical currents per unit width, Ic of 274-292 A/cm at 77 K and self-field were achieved for MOD-YBCO films grown on La xZr 1-xO y ( x = 0.4-0.6) films. These results indicate that LZO films can be grown with a broad compositional range and still support high performance YBCO coated conductors. In addition, epitaxial MOD La xZr 1-xO y ( x = 0.25) films were grown directly on biaxially textured Ni-3W substrates. About 3 μm thick YBCO films grown on a single MOD-LZO buffered Ni-3W substrates using pulsed laser deposition show a critical current density, Jc, of 0.55 MA/cm 2 ( Ic of 169 A/cm) at 77 K and 0.01 T. This work holds promise for a route for producing simplified buffer architecture for RABiTS based YBCO coated conductors.

  20. Modified Lanthanum Zirconium Oxide Buffer for Low-Cost, High Performance YBCO Coated Conductors

    SciTech Connect

    Paranthaman, Mariappan Parans; Sathyamurthy, Srivatsan; Li, Xiaoping; Specht, Eliot D; Wee, Sung Hun; Cantoni, Claudia; Goyal, Amit; Rupich, M. W.

    2010-01-01

    Lanthanum Zirconium Oxide, La2Zr2O7 (LZO) has been developed as a potential replacement barrier layer in the standard RABiTS three-layer architecture of physical vapor deposited CeO2 cap/YSZ barrier/Y2O3 seed/Ni-5W. The main focus of this research is to see (i) whether we can improve further the barrier properties of LZO; (ii) can we widen the LZO composition and still achieve the high performance?; and (iii) is it possible to reduce the number of buffer layers? We report a systematic investigation of the LZO film growth with varying compositions of La:Zr ratio in the La2O3-ZrO2 system. Using metal-organic deposition (MOD) process, we have grown smooth, crack-free, epitaxial thin films of LaxZr1-xOy (x = 0.2-0.6) on standard Y2O3 buffered Ni-5W substrates in short lengths. Detailed XRD studies indicate that a single epitaxial LZO phase without the (111) texture can be achieved in a wider compositional window of x = 0.2-0.6 in LaxZr1-xOy. Both CeO2 cap layers and MOD-YBCO films were grown 2 epitaxially on these modified LZO barriers. Transport property measurements indicate that we can achieve a higher critical current, Ic of 274-292 A/cm at 77 K and self-field on MOD-YBCO films grown on LaxZr1-xOy (x = 0.4-0.6) films. These results indicate that LZO films can be grown with a wider compositional window and still achieve high performance YBCO coated conductors. In addition, epitaxial MOD LaxZr1-xOy (x = 0.25) films were grown directly on biaxially textured Ni-3W substrates. About 3 m thick YBCO films with a Jc of 0.55 MA/cm2 at 77 K and 0.01 T were grown on a single MOD LZO buffered Ni-3W substrate using pulsed laser deposition. This work promises a route for producing simplified buffer architecture for RABiTS based YBCO coated conductors.

  1. Development of Long Coated Conductors with High In-field Ic Performance by PLD Method at High Production Rate

    NASA Astrophysics Data System (ADS)

    Ibi, Akira; Yoshida, Tomo; Izumi, Teruo; Shiohara, Yuh; Yokoe, Daisaku; Kato, Takeharu; Hirayama, Tsukasa

    We fabricated short samples and a 93 m long coated conductor (C. C.) of EuBa2Cu3O7-δ (EuBCO) with BaHfO3 (BHO) by the IBAD and the PLD methods, which exhibited the high in-field minimum Ic value, (Ic(min)), performance of 141.2 (77 K in 3 T) and 411.3 (65 K in 3 T) A/cm-w for a short sample, and 133.9 (77 K in 3 T) A/cm-w for 93 m long C. C. with 3.6 μm in thickness, respectively. Moreover, this long EuBCO with BHO coated conductor also showed high uniform longitudinal Ic distributions and n-value in magnetic fields. However, the deposition rate for obtaining the high in-field Ic performance was comparatively slow down to 10 μm/h. To realize the low production cost for EuBCO with BHO coated conductors, improvement of the deposition rate of the EuBCO with BHO layer with high Ic is required. To solve this problem, we optimized growth conditions including deposition conditions. One of the objectives of this work was changing the layer growth mode from the vapor-solid (VS) mode to the vapor-liquid-solid (VLS) one to fabricate EuBCO with BHO layers for achievement of high production rate and maintaining the high in-field Ic and Jc performance of the films deposited at slow deposition rates. As a result, we fabricated EuBCO with BHO coated conductors at a high deposition rate of about 40 μm/h and production rate of about 10 m/h, which revealed the Ic(min) value of 48.7 A/cm-w at 77 K in 3 T for 1.35 μm in thickness.

  2. Calculating transport AC losses in stacks of high temperature superconductor coated conductors with magnetic substrates using FEM

    NASA Astrophysics Data System (ADS)

    Ainslie, Mark D.; Flack, Tim J.; Campbell, Archie M.

    2012-01-01

    In this paper, the authors investigate the electromagnetic properties of stacks of high temperature superconductor (HTS) coated conductors with a particular focus on calculating the total transport AC loss. The cross-section of superconducting cables and coils is often modeled as a two-dimensional stack of coated conductors, and these stacks can be used to estimate the AC loss of a practical device. This paper uses a symmetric two dimensional (2D) finite element model based on the H formulation, and a detailed investigation into the effects of a magnetic substrate on the transport AC loss of a stack is presented. The number of coated conductors in each stack is varied from 1 to 150, and three types of substrate are compared: non-magnetic weakly magnetic and strongly magnetic. The non-magnetic substrate model is comparable with results from existing models for the limiting cases of a single tape (Norris) and an infinite stack (Clem). The presence of a magnetic substrate increases the total AC loss of the stack, due to an increased localized magnetic flux density, and the stronger the magnetic material, the further the flux penetrates into the stack overall. The AC loss is calculated for certain tapes within the stack, and the differences and similarities between the losses throughout the stack are explained using the magnetic flux penetration and current density distributions in those tapes. The ferromagnetic loss of the substrate itself is found to be negligible in most cases, except for small magnitudes of current. Applying these findings to practical applications, where AC transport current is involved, superconducting coils should be wound where possible using coated conductors with a non-magnetic substrate to reduce the total AC loss in the coil.

  3. RCE-DR, a novel process for coated conductor fabrication with high performance

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hun; Lee, Hunju; Lee, Jung-Woo; Choi, Soon-Mi; Yoo, Sang-Im; Moon, Seung-Hyun

    2014-04-01

    We report in detail on SuNAM’s reactive co-evaporation by deposition and reaction (RCE-DR) process. We have successfully fabricated a high performance GdBCO coated conductor (CC) with high throughput by the RCE-DR process, that consists of two steps for the deposition of elemental metal oxides and the conversion of cation oxides into the GdBCO superconducting phase. Constituting metals such as Gd, Ba and Cu were first deposited on LaMnO3 (LMO)-buffered IBAD-MgO templates at low temperatures and low pressures followed by a high temperature treatment step under high oxygen partial pressure for fast phase conversion. GdBCO CCs fabricated by RCE-DR showed excellent transport properties such as a critical current of 794 A cm-1 width at 77 K in self-field. With the RCE-DR process, we have achieved an overall processing speed of more than 120 m h-1 (in terms of a real process linear tape speed equivalent). SuNAM’s RCE-DR technique showed great potential as the highest throughput fabrication process compared with other methods developed previously for second generation high temperature superconducting wires, meeting the current and future need of industry in terms of price and production speed.

  4. Dual Ion Assist Beam Deposition of Magnesium Oxide for Coated Conductors

    NASA Astrophysics Data System (ADS)

    Groves, J. R.; Arendt3, P. N.; Holesinger, T. G.; Hammond, R. H.; Foltyn, S. R.; DePaula, R. F.; Stan, L.; Usov, I. O.

    2006-03-01

    Ion Beam Assisted Deposition (IBAD) of Magnesium Oxide (MgO) has been proven to be a viable route for producing template films used to deposit high quality YBCO coated conductors on flexible polycrystalline metal substrates. Here we will discuss improvements in this process using a dual ion assist beam configuration. Dual ion assist beam deposition of MgO reduces the requirements for substrate surface finishing while maintaining comparable film quality (phi scan full-width at half-maximum values between 7 and 8 degrees). Furthermore, this adaptation of the IBAD process eliminates the degradation of MgO texture observed in thick IBAD MgO films deposited on silicon nitride. We have deposited films up to 50 nanometers thick without degradation of in-plane texture. Increasing the MgO thickness increases the chemical stability of the template layer and can eliminate the necessity for subsequent buffer layers or the application of the homoepitaxial MgO layer needed to stabilize the thin, conventional IBAD MgO layer. Initial results of subsequently deposited YBCO on these dual assist ion beam MgO templates are quite promising.

  5. Long length oxide template for YBCO coated conductor prepared by surface-oxidation epitaxy method

    NASA Astrophysics Data System (ADS)

    Watanabe, Tomonori; Matsumoto, Kaname; Maeda, Toshihiko; Tanigawa, Toru; Hirabayashi, Izumi

    2001-08-01

    A 50 m long, biaxially textured NiO buffer layer for epitaxial growth ofYBa 2Cu 3O 7- δ (YBCO) film has been fabricated on the long cube textured nickel tape using surface-oxidation epitaxy (SOE) method. The SOE-NiO layers were highly {1 0 0} <0 0 1> textured. The full width at half maximum of 10-14.5° from X-ray φ-scan ( Δφ) was in the range of 10-14.5° through the whole length. The critical current density ( Jc) values exceeding 0.3 MA/cm 2 (77 K, 0 T) have been obtained in short samples of YBCO films on NiO/Ni tapes, by using thin MgO cap layer. Thirty meters long Ni-clad Ni-20wt.%Cr (Ni/NiCr) and Ni-clad austenitic stainless steel (Ni/SS) tapes were also prepared for YBCO coated conductors with higher strength and lower magnetism than those of pure nickel tape. Highly {1 0 0} <0 0 1> textured NiO layers were formed on those textured composite tapes by SOE method as same as on cube textured pure nickel tapes. YBCO films with Jc of 0.1 MA/cm 2 (77 K, 0 T) have been obtained on MgO/SOE-NiO layer of short Ni/NiCr composite tape.

  6. Fabrication of YSZ buffer layer by single source MOCVD technique for YBCO coated conductor

    NASA Astrophysics Data System (ADS)

    Jun, Byung-Hyuk; Sun, Jong-Won; Kim, Ho-Jin; Lee, Dong-Wook; Jung, Choong-Hwan; Park, Soon-Dong; Kim, Chan-Joong

    2003-10-01

    Yttria stabilized zirconia (YSZ) buffer layers were deposited by a metal organic chemical vapor deposition technique using a single liquid source for the application of YBa 2Cu 3O 7- δ (YBCO) coated conductor. Y:Zr mole ratio was 0.2:0.8, and tetrahydrofuran (THF) was used as a solvent. The (1 0 0) single crystal MgO substrate was used for searching the deposition conditions. Bi-axially oriented CeO 2 and NiO films were fabricated on {1 0 0} <0 0 1> textured Ni substrate by the same method and used as templates. At a constant working pressure of 10 Torr, the deposition temperatures (660-800 °C) and oxygen flow rates (100-500 sccm) were changed to find the optimum deposition condition. The best (1 0 0) oriented YSZ film on MgO was obtained at 740 °C and O 2 flow rate of 300 sccm. For a YSZ buffer layer with this deposition condition on a CeO 2/Ni template, full width half maximum values of the in-plane ( ϕ-scan) and out-of-plane ( ω-scan) alignments were 10.6° and 9.8°, respectively. The SEM image of YSZ film on CeO 2/Ni showed surface morphologies without microcracks. The film deposition rate was about 100 nm/min.

  7. Modeling of screening currents in coated conductor magnets containing up to 40000 turns

    NASA Astrophysics Data System (ADS)

    Pardo, E.

    2016-08-01

    Screening currents caused by varying magnetic fields degrade the homogeneity and stability of the magnetic fields created by REBCO coated conductor coils. They are responsible for the AC loss; which is also important for other power applications containing windings, such as transformers, motors and generators. Since real magnets contain coils exceeding 10000 turns, accurate modeling tools for this number of turns or above are necessary for magnet design. This article presents a fast numerical method to model coils with no loss of accuracy. We model a 10400-turn coil for its real number of turns and coils of up to 40000 turns with continuous approximation, which introduces negligible errors. The screening currents, the screening current induced field (SCIF) and the AC loss is analyzed in detail. The SCIF is at a maximum at the remnant state with a considerably large value. The instantaneous AC loss for an anisotropic magnetic-field dependent J c is qualitatively different than for a constant J c , although the loss per cycle is similar. Saturation of the magnetization currents at the end pancakes causes the maximum AC loss at the first ramp to increase with J c . The presented modeling tool can accurately calculate the SCIF and AC loss in practical computing times for coils with any number of turns used in real windings, enabling parameter optimization.

  8. Voltage-ampere characteristics of YBCO coated conductor under inhomogeneous oscillating magnetic field

    NASA Astrophysics Data System (ADS)

    Geng, J.; Shen, B.; Li, C.; Zhang, H.; Matsuda, K.; Li, J.; Zhang, X.; Coombs, T. A.

    2016-06-01

    Direct current carrying type II superconductors present a dynamic resistance when subjected to an oscillating magnetic field perpendicular to the current direction. If a superconductor is under a homogeneous field with high magnitude, the dynamic resistance value is nearly independent of transport current. Hoffmann and coworkers [Hoffmann et al., IEEE Trans. Appl. Supercond. 21, 1628 (2011)] discovered, however, flux pumping effect when a superconducting tape is under an inhomogeneous field orthogonal to the tape surface generated by rotating magnets. Following their work, we report the whole Voltage-Ampere (V-I) curves of an YBCO coated conductor under permanent magnets rotating with different frequencies and directions. We discovered that the two curves under opposite rotating directions differ from each other constantly when the transport current is less than the critical current, whereas the difference gradually reduces after the transport current exceeds the critical value. We also find that for different field frequencies, the difference between the two curves decreases faster with lower field frequency. The result indicates that the transport loss is dependent on the relative direction of the transport current and field travelling, which is distinct from traditional dynamic resistance model. The work may be instructive for the design of superconducting motors.

  9. Microstructure Characteristics of High Lift Factor MOCVD REBCO Coated Conductors With High Zr Content

    SciTech Connect

    Galstyan, E; Gharahcheshmeh, MH; Delgado, L; Xu, AX; Majkic, G; Selvamanickam, V

    2015-06-01

    We report the microstructural characteristics of high levels of Zr-added REBa2Cu3O7-x (RE = Gd, Y rare earth) coated conductors fabricated by Metal Organic Chemical Vapor Deposition (MOCVD). The enhancements of the lift factor defined as a ratio of the in-field (3 T, B parallel to c-axis) critical current density (J(c)) at 30 K and self-field J(c) at 77 K have been achieved for Zr addition levels of 20 and 25 mol% via optimization of deposition parameters. The presence of strong flux pinning is attributed to the aligned nanocolumns of BaZrO3 and nanoprecipitates embedded in REBa2Cu3O7-x matrix with good crystal quality. A high density of BZO nanorods with a typical size 6-8 nm and spacing of 20 nm has been observed. Moreover, the high Zr content was found to induce a high density of intrinsic defects, including stacking faults and dislocations. The correlation between in-field performance along the c-axis and microstructure of (Gd, Y) BCO film with a high level of Zr addition is discussed.

  10. Future prospects of high Tc superconductors-coated conductors and their applications

    NASA Astrophysics Data System (ADS)

    Shiohara, Yuh; Yoshizumi, Masateru; Takagi, Yuji; Izumi, Teruo

    2013-01-01

    The research and development of high-temperature superconducting wires, especially yttrium-based coated conductors (CCs), and their energy applications have been expected to reduce CO2 emissions. This article reviews recent progress in this area, mainly focusing on the results obtained by national projects in Japan. The Ic (critical current) × L (wire length) value of CCs has been improved to reach 466,752 A m (572 A/cm-W, 816 m), which exceeds that of Bi-system wires. CCs have also been improved in terms of in-field performance and AC loss reduction to meet market requirements. Power applications such as superconducting magnetic energy storage (SMES) systems, power cables and transformers have been developed using CCs in the current project. Because of fundamental research on high-capacity power cables, a low AC loss of 0.8 W/m-ph at 3 kA and 73.7 K was achieved. System design and fundamental research were performed on a 2GJ-class SMES system and a 20 MVA-class transformer. Based on the technologies developed by the end of the current project (FY2012), the innovation process of those applications will reach the implementation stage, where the long-term reliability tests will be performed. The process is expected to reach the penetration and propagation stage around 2020.

  11. Rapid Doubling of the Critical Current of YBa2Cu3O7-δ Coated Conductors

    NASA Astrophysics Data System (ADS)

    Welp, U.; Leroux, M.; Kihlstrom, K. J.; Holleis, S.; Rupich, M. W.; Sathyamurthy, S.; Fleshler, S.; Sheng, H. P.; Miller, D. J.; Eley, S.; Civale, L.; Niraula, P. M.; Kayani, A.; Kwok, W. K.

    We demonstrate the doubling of the critical current density of production-line REBCO coated conductors (CCs) in fields of 6 T ||c at 27 K by irradiation with a 3.5-MeV oxygen ion beam. This doubling of Jc is achieved within one second or less opening an industrially viable approach to address a persisting challenge, namely the greatly reduced performance of CCs in even modest applied magnetic fields. TEM images reveal that the enhanced critical current is due to finely dispersed small clusters approximately 5 nm in diameter. The major effect of the irradiation-induced defects is the reduction of the field-dependence of Jc, which we attribute to the mixed pinning landscape composed of strong pre-existing pin sites and the finely dispersed irradiation-induced defects. Work supported by the Center for Emergent Superconductivity, an EFRC funded by the U.S. Department of Energy, Office of Basic Energy Sciences. Patterning and microstructural characterization were performed at the Center for Nanoscale Materials, an Office of Science user facility, supported by the Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

  12. Enhanced critical currents of commercial 2G superconducting coated conductors through proton irradiation

    NASA Astrophysics Data System (ADS)

    Welp, Ulrich; Leroux, M.; Kihlstrom, K. J.; Kwok, W.-K.; Koshelev, A. E.; Miller, D. J.; Rupich, M. W.; Fleshler, S.; Malozemoff, A. P.; Kayani, A.

    2015-03-01

    We report on magnetization and transport measurements of the critical current density, Jc, of commercial 2G YBCO coated conductors before and after proton irradiation. The samples were irradiated along the c-axis with 4 MeV protons. Proton irradiation produces a mixed pinning landscape composed of pre-existing rare earth particles and a uniform distribution of irradiation induced nm-sized defects. This pinning landscape strongly reduces the suppression of Jc in magnetic fields resulting in a doubling of Jc in a field of ~ 4T. The irradiation dose-dependence of Jc is characterized by a temperature and field dependent sweat spot that at 5 K and 6 T occurs around 20x1016 p/cm2. Large-scale time dependent Ginzburg-Landau simulations yield a good description of our results. This work supported by the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the U.S. D.O.E., Office of Science, Office of Basic Energy Sciences (KK, ML, AEK) and by the D.O.E, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357 (UW, WKK).

  13. Inclined-substrate deposition of biaxially textured magnesium oxide thin films for YBCO coated conductors.

    SciTech Connect

    Ma, B.; Li, M.; Jee, Y. A.; Koritala, R. E.; Fisher, B. L.; Balachandran, U.; Energy Technology

    2002-02-01

    Highly textured MgO films were grown by the inclined-substrate deposition (ISD) technique at a high deposition rate. A columnar grain with a roofing-tile-shaped surface was observed in these MgO films. X-ray pole figure, and {phi}- and {omega}-scan were used to characterize in-plane and out-of-plane textures. MgO films deposited when the incline angle {alpha} was 55 and 30 degrees exhibited the best in-plane and out-of-plane texture, respectively. High-quality YBCO films were epitaxially grown on ISD-MgO-buffered Hastelloy C substrates by pulsed laser deposition. {Tc}=88 K, with sharp transition, and j{sub c} values of {approx}2x10{sup 5} A/cm{sup 2} at 77 K in zero field were observed on films 5 mm wide and 1 cm long. This work has demonstrated that biaxially textured ISD MgO buffer layers deposited on metal substrates are excellent candidates for fabrication of high-quality YBCO coated conductors.

  14. Biaxially aligned template films fabricated by inclined-substrate deposition for YBCO-coated conductor applications.

    SciTech Connect

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

    2002-08-12

    Inclined substrate deposition (ISD) has the potential for rapid production of high-quality biaxially textured buffer layers, which are important for YBCO-coated conductor applications. We have grown biaxially textured MgO films by ISD at deposition rates of 20-100 {angstrom}/sec. Columnar grains with a roof-tile surface structure were observed in the ISD-MgO films. X-ray pole figure analysis revealed that the (002) planes of the ISD-MgO films are tilted at an angle from the substrate normal. A small {phi}-scan full-width at half maximum (FWHM) of {approx}9{sup o} was observed on MgO films deposited at an inclination angle of 55{sup o}. In-plane texture in the ISD MgO films developed in the first 0.5 {micro}m from the interface, then stabilized with further increases in film thickness. YBCO films deposited by pulsed laser deposition on ISD-MgO buffered Hastelloy C276 substrates were biaxially aligned with the c-axis parallel to the substrate normal. T{sub c} of 91 K with a sharp transition and transport J{sub c} of 5.5 x 10{sup 5} A/cm{sup 2} at 77 K in self-field were measured on a YBCO film that was 0.46-{micro}m thick, 4-mm wide, 10-mm long.

  15. On the use of copper-based substrates for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Vannozzi, A.; Fabbri, F.; Augieri, A.; Angrisani Armenio, A.; Galluzzi, V.; Mancini, A.; Rizzo, F.; Rufoloni, A.; Padilla, J. A.; Xuriguera, E.; De Felicis, D.; Bemporad, E.; Celentano, G.

    2014-05-01

    It is well known that the recrystallization texture of heavily cold-rolled pure copper is almost completely cubic. However, one of the main drawbacks concerning the use of pure copper cube-textured substrates for YBCO coated conductor is the reduced secondary recrystallization temperature. The onset of secondary recrystallization (i.e., the occurrence of abnormal grains with unpredictable orientation) in pure copper substrate was observed within the typical temperature range required for buffer layer and YBCO processing (600-850 °C). To avoid the formation of abnormal grains the effect of both grain size adjustment (GSA) and recrystallization annealing was analyzed. The combined use of a small initial grain size and a recrystallization two-step annealing (TSA) drastically reduced the presence of abnormal grains in pure copper tapes. Another way to overcome the limitation imposed by the formation of abnormal grains is to deposit a buffer layer at temperatures where secondary recrystallization does not occur. For example, La2Zr2O7 (LZO) film with a high degree of epitaxy was grown by metal-organic decomposition (MOD) at 1000 °C on pure copper substrate. In several samples the substrate underwent secondary recrystallization. Our experiments indicate that the motion of grain boundaries occurring during secondary recrystallization process does not affect the quality of LZO film.

  16. Roebel assembled coated conductor cables (RACC): Ac-Losses and current carrying potential

    NASA Astrophysics Data System (ADS)

    Frank, A.; Heller, R.; Goldacker, W.; Kling, A.; Schmidt, C.

    2008-02-01

    Low ac-loss HTS cables for transport currents well above 1 kA are required for application in transformers and generators and are taken into consideration for future generations of fusion reactor coils. Coated conductors (CC) are suitable candidates for high field application at an operation temperature in the range 50-77 K. Ac-field applications require cables with low ac-losses and hence twisting of the individual strands. We solved this problem using the Roebel technique. Short lengths of Roebel bar cables were prepared from industrial DyBCO and YBCO-CC. Meander shaped tapes of 4 or 5 mm width with twist pitches of 123 or 127 mm were cut from the 10 or 12 mm wide CC tapes using a specially designed tool. Eleven or twelve of these strands were assembled to a cable. The electrical and mechanical connection of the tapes was achieved using a silver powder filled conductive epoxy resin. Ac-losses of a short sample in an external ac-field were measured as a function of frequency and field amplitude as well as the coupling current decay time constant. We discuss the results in terms of available theories and compare measured time constants in transverse field with measured coupling losses. Finally the potential of this cable type for ac-use is discussed with respect to ac-losses and current carrying capability.

  17. The mechanism of thermal runaway due to continuous local disturbances in the YBCO-coated conductor coil winding

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Y.; Okuyama, E.; Nakagome, H.; Takematsu, T.; Takao, T.; Hamada, M.; Matsumoto, S.; Kiyoshi, T.; Takizawa, A.; Takahashi, M.; Maeda, H.

    2012-07-01

    Though YBCO coils are stable against transient disturbances such as conductor motion, they suffer from thermal runaway at a current below the coil critical current due to continuous local disturbances attributed to partial degradation of the conductor in the coil winding. Continuous heat generation in the degraded layer induces thermal runaway in adjacent layers; thermal runaway does not occur in the degraded layer spontaneously due to the small n index of the degraded YBCO-coated conductor. The thermal runaway current depends on the cooling conditions of the winding. For a paraffin-impregnated YBCO coil under quasi-adiabatic conditions, the thermal runaway current is far below the coil critical current, while it is close to the coil critical current in the case of a dry-wound coil. The permissible temperature rise following a thermal runaway for YBCO conductors in the degraded layer is demonstrated to be 340 K. If the YBCO coils are operated at a temperature below 20 K, the current density, typically 600-800 A mm-2, is much higher than that at 77 K. Therefore, the time interval between thermal runaway initiation and the melting temperature becomes less than 0.5 s, posing a difficult problem for protection; i.e., thermal runaway due to continuous local disturbances is hazardous to the safe operation of high current density YBCO coils.

  18. Broad Temperature Pinning Study of 15 mol.% Zr-Added (Gd, Y)-Ba-Cu-O MOCVD Coated Conductors

    SciTech Connect

    Xu, AX; Khatri, N; Liu, YH; Majkic, G; Galstyan, E; Selvamanickam, V; Chen, YM; Lei, CH; Abraimov, D; Hu, XB; Jaroszynski, J; Larbalestier, D

    2015-06-01

    BaZrO3 (BZO) nanocolumns have long been shown to be very effective for raising the pinning force F-p of REBa2Cu3Ox (REBCO, where RE = rare earth) films at high temperatures and recently at low temperatures too. We have successfully incorporated a high density of BZO nanorods into metal organic chemical vapor deposited (MOCVD) REBCO coated conductors via Zr addition. We found that, compared to the 7.5% Zr-added coated conductor, dense BZO nanorod arrays in the 15% Zr-added conductor are effective over the whole temperature range from 77 K down to 4.2 K. We attribute the substantially enhanced J(c) at 30 K to the weak uncorrelated pinning as well as the strong correlated pinning. Meanwhile, by tripling the REBCO layer thickness to similar to 2.8 mu m, the engineering critical current density J(e) at 30 K exceeds J(e) of optimized Nb-Ti wires at 4.2 K.

  19. Numerical models for ac loss calculation in large-scale applications of HTS coated conductors

    NASA Astrophysics Data System (ADS)

    Quéval, Loïc; Zermeño, Víctor M. R.; Grilli, Francesco

    2016-02-01

    Numerical models are powerful tools to predict the electromagnetic behavior of superconductors. In recent years, a variety of models have been successfully developed to simulate high-temperature-superconducting (HTS) coated conductor tapes. While the models work well for the simulation of individual tapes or relatively small assemblies, their direct applicability to devices involving hundreds or thousands of tapes, e.g., coils used in electrical machines, is questionable. Indeed, the simulation time and memory requirement can quickly become prohibitive. In this paper, we develop and compare two different models for simulating realistic HTS devices composed of a large number of tapes: (1) the homogenized model simulates the coil using an equivalent anisotropic homogeneous bulk with specifically developed current constraints to account for the fact that each turn carries the same current; (2) the multi-scale model parallelizes and reduces the computational problem by simulating only several individual tapes at significant positions of the coil’s cross-section using appropriate boundary conditions to account for the field generated by the neighboring turns. Both methods are used to simulate a coil made of 2000 tapes, and compared against the widely used H-formulation finite-element model that includes all the tapes. Both approaches allow faster simulations of large number of HTS tapes by 1-3 orders of magnitudes, while maintaining good accuracy of the results. Both models can therefore be used to design and optimize large-scale HTS devices. This study provides key advancement with respect to previous versions of both models. The homogenized model is extended from simple stacks to large arrays of tapes. For the multi-scale model, the importance of the choice of the current distribution used to generate the background field is underlined; the error in ac loss estimation resulting from the most obvious choice of starting from a uniform current distribution is revealed.

  20. Fabrication and Characterization of YBCO Coated Conductors by Inclined Substrate Deposition

    NASA Astrophysics Data System (ADS)

    Ma, B.; Balachandran, U.; Xu, Y.; Bhattacharya, R.

    2006-03-01

    Inclined substrate deposition (ISD) is an effective method for rapid fabrication of high-quality template layers for YBCO-coated conductors. We have deposited biaxially textured ISD-MgO films on flexible metallic tapes in a reel-to-reel system by electron-beam evaporation at rapid deposition rates, 2-10 nmṡs-1. Strontium ruthenium oxide (SRO) buffer and YBCO films were grown by pulsed laser deposition (PLD). Pole figure analysis of a meter-long ISD-MgO tape was carried out by X-ray diffraction using a Bruker's D8 DISCOVER equipped with GADDS (general area detection diffraction system). The c-axis of the ISD-MgO film was tilted away from substrate normal. A full-width at half maximum (FWHM) of ≈10° was observed from the φ-scan of the MgO (002) diffraction measured on samples deposited with 35° inclination angle. Surface morphology measured by atomic force microscopy revealed a roof-tile shaped structure for the ISD-MgO films. Through the use of the SRO buffer, biaxial alignment in the YBCO film deposited on the ISD-MgO template was improved. The φ-scan FWHM was 5.8° for the YBCO (005) diffraction. We have measured the critical transition temperature Tc = 91 K and transport critical current density Jc >1.6×106 Aṡcm-2 at 77 K in self-field on a SRO-buffered YBCO film grown with ISD-MgO architecture.

  1. High-material yield fabrication of YBCO coated conductors by Nd:YAG-PLD system

    NASA Astrophysics Data System (ADS)

    Ono, I.; Ichino, Y.; Yoshida, Y.; Yoshizumi, M.; Izumi, T.; Shiohara, Y.

    In order to fabricate superconducting coated conductors with lower cost, fabrication processes are required high material yield. We report an improvement of the material yield of YBCO films prepared by inside-plume Nd:YAG pulsed laser deposition method on metal substrates with an architecture of CeO2/LMO/IBAD-MgO/GZO/HastelloyTM. In this study, we shortened a distance from the target to the substrate (dT-S) in order to improve the material yield. Additionally, we have used Nd:YAG laser because initial and running costs are anticipated to be lower than those of excimer laser. As a result, by shorting the dT-S from 40 mm to 20 mm, the material yield increased on 10 mm×10 mm substrates. Additionally, by changing the O2 pressure (PO2) from 40 Pa to 400 Pa at dT-S = 20 mm, the material yield had a local maximal value of 18.6% at PO2=200 Pa. On multi-turn (MT) metal substrates, the material yield reached 56.0%. However, the critical current density (Jc) of the YBCO film which was deposited at dT-S = 20 mm and PO2=200 Pa on the 10 mm×10 mm substrate was 1.2 MA/cm2 at the edges and 0.2 MA/cm2 at the center at 77 K in self-field, although the YBCO films showed good aligned crystal textures. In order to improve this non-uniformity, we tilted the surface normal of the target 15 degree from a line connecting target and substrate. As a result, we achieved the uniformity in deposition rate. Then, we prepared YBa1.78Cu2.9Oy target to fabricate YBCO films with stoichiometric composition and obtained the uniform-high Jc.

  2. Note: Effective anvil size for transverse delamination test of rare-earth-Ba₂Cu₃Oy coated conductor tapes.

    PubMed

    Shin, Hyung-Seop; Gorospe, Alking B; Dedicatoria, Marlon J

    2015-10-01

    In coated conductor (CC) tapes used in magnet and coil applications, delamination due to excessive transverse tensile stresses is still one of the major issues that need considerations. Recently, several methods in evaluating the delamination strength of CC tapes are being used. In the case of anvil test, size of the anvils will be an important factor considering its applications (i.e., superconducting coil impregnation). In this study, delamination strength of CC tape was examined using different upper anvil sizes and their effects were discussed. Finally, reasonable sizes of upper anvil to be used were proposed considering the application conditions. PMID:26521009

  3. Growth of lanthanum manganate buffer layers for coated conductors via a metal-organic decomposition process

    NASA Astrophysics Data System (ADS)

    Venkataraman, Kartik

    LaMnO3 (LMO) was identified as a possible buffer material for YBa2Cu3O7-x conductors due to its diffusion barrier properties and close lattice match with YBa2Cu 3O7-x. Growth of LMO films via a metal-organic decomposition (MOD) process on Ni, Ni-5at.%W (Ni-5W), and single crystal SrTiO3 substrates was investigated. Phase-pure LMO was grown via MOD on Ni and SrTiO 3 substrates at temperatures and oxygen pressures within a thermodynamic "process window" wherein LMO, Ni, Ni-5W, and SrTiO3 are all stable components. LMO could not be grown on Ni-5W in the "process window" because tungsten diffused from the substrate into the overlying film, where it reacted to form La and Mn tungstates. The kinetics of tungstate formation and crystallization of phase-pure LMO from the La and Mn acetate precursors are competitive in the temperature range explored (850--1100°C). Temperatures <850°C might mitigate tungsten diffusion from the substrate to the film sufficiently to obviate tungstate formation, but LMO films deposited via MOD require temperatures ≥850°C for nucleation and grain growth. Using a Y2O3 seed layer on Ni-5W to block tungsten from diffusing into the LMO film was explored; however, Y2O3 reacts with tungsten in the "process window" at 850--1100°C. Tungsten diffusion into Y2O3 can be blocked if epitaxial, crack-free NiWO4 and NiO layers are formed at the interface between Ni-5W and Y2O3. NiWO 4 only grows epitaxially if the overlying NiO and buffer layers are thick enough to mechanically suppress (011)-oriented NiWO4 grain growth. This is not the case when a bare 75 nm-thick Y2O3 film on Ni-5W is processed at 850°C. These studies show that the Ni-5W substrate must be at a low temperature to prevent tungsten diffusion, whereas the LMO precursor film must be at elevated temperature to crystallize. An excimer laser-assisted MOD process was used where a Y2O 3-coated Ni-5W substrate was held at 500°C in air and the pulsed laser photo-thermally heated the Y2O3 and LMO

  4. Engineered oxide thin films as 100% lattice match buffer layers for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Akin, Y.; Heiba, Z. K.; Sigmund, W.; Hascicek, Y. S.

    2003-12-01

    One of the most important qualities of buffer layers for RE-BCO coated conductors' growth is close lattice match with RE-BCO. However, there is no natural material with a 100% lattice match with RE-BCO. In this study mixtures of europium oxide (Eu 2O 3) and ytterbium oxide (Yb 2O 3), (Eu 1- uYb u) 2O 3 (0.0⩽ u⩽1.0), were investigated as a candidate buffer layer that could have same lattice parameter as YBa 2Cu 3O 7- δ(YBCO). Because the pseudocubic lattice parameter of Eu 2O 3 is bigger, and that of Yb 2O 3 is smaller than lattice parameter of YBCO, and the mixed oxides with appropriate ratio would have same lattice parameter of YBCO. The mixtures were prepared using metal-organic precursor by sol-gel process, and it was found that all mixed samples are single phase, complete solid solutions, and have same crystal system over the whole range of " u". Lattice parameters of mixed (Eu 1- uYb u) 2O 3 oxide powders were changed between 10.86831 and 10.42828 Å which are lattice parameter of Eu 2O 3 and Yb 2O 3, respectively by changing the ratio of Eu/Yb in the mixture. Phase and lattice parameter analysis revealed that pseudocubic lattice parameter of (Eu 0.893Yb 0.107) 2O 3 is 3.82 Å which is same as the lattice parameter of YBCO. Textured (Eu 0.893Yb 0.107) 2O 3 buffer layers were grown on biaxially textured-Ni (1 0 0) substrates. The solution was prepared from Europium and Ytterbium 2,4-pentadioanate, and was deposited on the Ni substrates using a reel-to-reel sol-gel dip coating system. The textured films were annealed at 1150 °C for 10 min under 4% H 2-Ar gas flow. Extensive texture analysis has been done to characterize the texture of (Eu 0.893Yb 0.107) 2O 3 buffer layers. X-ray diffraction (XRD) of the buffer layer showed strong out-of-plane orientation on Ni tape. The (Eu 0.893Yb 0.107) 2O 3 (2 2 2) pole figure indicated a single cube-on-cube textured structure. The omega and phi scans revealed good out-of-plane and in-plane alignments. The full

  5. Change in fatigue property and its relation to critical current for YBCO coated conductor with additional Cu layer

    NASA Astrophysics Data System (ADS)

    Yoshida, Y.; Hojo, M.; Sugano, M.; Adachi, T.; Inoue, Y.; Shikimachi, K.; Hirano, N.; Nagaya, S.

    2009-10-01

    YBa 2Cu 3O 7-δ, (YBCO) coated conductors with an additional Cu layer are expected to be applied as coils used in superconducting magnetic energy storage, SMES. In the operation of SMES, large cyclic hoop stress is applied to the coated conductor in the longitudinal direction. In the present study, we carried out fatigue tests in liquid nitrogen, LN 2, and measured the critical current, I c, after a specific number of fatigue cycles to clarify its fatigue fracture mechanism. All fatigue tests were carried out under a stress ratio (the ratio of the minimum to maximum load) of 0.5. The frequency of stress cycling was 30 Hz. Our results showed that the addition of a Cu layer increased the fatigue strength after 10 6 cycles, F, by about 19%. Decrease of I c was more than 30% of the initial critical current, I c0, without loading at the point of final overall fracture when the maximum load in the stress cycles was close to that corresponding to irreversible strain. Furthermore, microscopic observation and the change in I c showed that fatigue fracture mainly initiated from the Hastelloy C-276 substrate. Fatigue fracture also initiated from the Cu layer, but only when the maximum load was approximately F.

  6. Development of a superconducting joint between a GdBa2Cu3O7-δ-coated conductor and YBa2Cu3O7-δ bulk: towards a superconducting joint between RE (Rare Earth) Ba2Cu3O7-δ-coated conductors

    NASA Astrophysics Data System (ADS)

    Jin, Xinzhe; Yanagisawa, Yoshinori; Maeda, Hideaki; Takano, Yoshiki

    2015-07-01

    We have started to develop a superconducting bridge joint between two GdBa2Cu3O7-δ (Gd123)-coated conductors, where both conductors are placed in an end-to-end arrangement on the surface of a melt-textured YBCO (including Y2BaCuO5 and YBa2Cu3O7-δ) bulk, which acts as a superconducting medium between the coated conductors. As a first step in the development, one half of the bridge joint assembly was modeled and investigated. Experimental results achieved are as follows: (a) the higher-melting-temperature textured Gd123-coated conductor acts as a seed for the melt texture of the YBa2Cu3O7-δ (Y123) bulk, and (b) the superconducting phase continues across the Y123/Gd123 boundary. The critical current of the joint model is 10 A, which is about 10% of the original Gd123-coated conductor, at 77 K in a self-magnetic field. These results are considered to be extensible to the superconducting bridge joint between the Gd123-coated conductors.

  7. Effects on Jc of pinning center morphology for multiple-in-line-damage in coated conductor and bulk, melt-textured HTS

    NASA Astrophysics Data System (ADS)

    Weinstein, R.; Parks, D.; Sawh, R.-P.; Mayes, B.; Gandini, A.; Goyal, A.; Chen, Y.; Selvamanickam, V.

    2009-12-01

    The properties of discontinuous aligned pinning centers (PCs) created by high-energy heavy-ions are compared for bulk melt-textured and coated conductor HTS. Properties of PCs, which increase Jc (pinning potential and entanglement), and negative properties which decrease Jc (e.g., decreased Tc and percolation paths) are evaluated. Mechanisms are proposed to explain the very large increases in Jc resulting from multiple-in-line-damage (MILD) compared to continuous columnar pinning centers (CCPC). In particular, a mechanism which results in fluxoid entanglement, even for parallel (unsplayed) PCs, is discussed. The same mechanism is found to also account for restoration of much of the pinning potential expected to be lost due to the gaps in MILD PCs. It also accounts for the fact that at high fluence, Jc increases as fluence is increased, instead of decreasing as expected. The very low self-field in coated conductor permits separation of the negative and positive effects of PCs. It is found that parameters developed to quantify the negative effects in bulk melt-textured YBCO, by 63 GeV U 238 ions, successfully describe damage to 2.1 μm thick coated conductor by 1 GeV Ru 44 ions. Coated conductor at 77 K and self-field is generally known to have Jc about 100 times that of melt-textured YBCO. However, at 77 K and applied field of 1 T, when both forms of HTS are processed with comparable numbers of near-optimum MILD PCs, the difference in Jc is reduced to a factor of 1.3-2. Whereas Jc for melt-textured YBCO increased sharply, by a factor of up to 16.8 for high-fluence MILD PCs, Jc in coated conductor increased by a smaller factor of 2.5-3.0. Nevertheless, 2.1 μm thick coated conductor, with near-optimum MILD PCs, exhibits Jc = 543 kA/cm 2 at 77 K and applied field of 1.0 T, and Ic = 114 A/cm-width of conductor. This is the highest value we find in the literature. The phenomenology developed indicates that for optimum MILD PCs in coated conductor, Jc ∼ 700 ± 70 k

  8. Low AC Loss YBCO Coated Conductor Geometry by Direct Inkjet Printing

    SciTech Connect

    Rupich, Martin, Dr.; Duckworth, Robert, Dr.

    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.

  9. Roebel cables from REBCO coated conductors: a one-century-old concept for the superconductivity of the future

    NASA Astrophysics Data System (ADS)

    Goldacker, Wilfried; Grilli, Francesco; Pardo, Enric; Kario, Anna; Schlachter, Sonja I.; Vojenčiak, Michal

    2014-09-01

    Energy applications employing high-temperature superconductors (HTS), such as motors/generators, transformers, transmission lines and fault current limiters, are usually operated in the alternate current (ac) regime. In order to be efficient, the HTS devices need to have a sufficiently low value of ac loss, in addition to the necessary current-carrying capacity. Most applications are operated with currents beyond the current capacity of single conductors and consequently require cabled conductor solutions with much higher current carrying capacity, from a few kA up to 20-30 kA for large hydro-generators. A century ago, in 1914, Ludwig Roebel invented a low-loss cable design for copper cables, which was successively named after him. The main idea behind Roebel cables is to separate the current in different strands and to provide a full transposition of the strands along the cable direction. Nowadays, these cables are commonly used in the stator of large generators. Based on the same design concept of their conventional material counterparts, HTS Roebel cables from REBCO coated conductors were first manufactured at the Karlsruhe Institute of Technology and have been successively developed in a number of varieties that provide all the required technical features such as fully transposed strands, high transport currents and low ac losses, yet retaining enough flexibility for a specific cable design. In the past few years a large number of scientific papers have been published on the concept, manufacturing and characterization of such cables. Therefore it is timely for a review of those results. The goal is to provide an overview and a succinct and easy-to-consult guide for users, developers, and manufacturers of this kind of HTS cable.

  10. Electro-mechanical properties of REBCO coated conductors from various industrial manufacturers at 77 K, self-field and 4.2 K, 19 T

    NASA Astrophysics Data System (ADS)

    Barth, C.; Mondonico, G.; Senatore, C.

    2015-04-01

    Rare-Earth-barium-copper-oxide tapes are now available from several industrial manufacturers and are very promising conductors in high field applications. Due to diverging materials and deposition processes, these manufacturers’ tapes can be expected to differ in their electro-mechanical and mechanical properties. For magnets designers, these are together with the conductors’ in-field critical current performance of the highest importance in choosing a suitable conductor. In this work, the strain and stress dependence of the current carrying capabilities as well as the stress and strain correlation are investigated for commercial coated conductors from Bruker HTS, Fujikura, SuNAM, SuperOx and SuperPower at 77 K, self-field and 4.2 K, 19 T.

  11. A 1 kA-class cryogen-free critical current characterization system for superconducting coated conductors.

    PubMed

    Strickland, N M; Hoffmann, C; Wimbush, S C

    2014-11-01

    A cryogenic electrical transport measurement system is described that is particularly designed to meet the requirements for routine and effective characterization of commercial second generation high-temperature superconducting (HTS) wires in the form of coated conductors based on YBa2Cu3O7. Specific design parameters include a base temperature of 20 K, an applied magnetic field capability of 8 T (provided by a HTS split-coil magnet), and a measurement current capacity approaching 1 kA. The system accommodates samples up to 12 mm in width (the widest conductor size presently commercially available) and 40 mm long, although this is not a limiting size. The sample is able to be rotated freely with respect to the magnetic field direction about an axis parallel to the current flow, producing field angle variations in the standard maximum Lorentz force configuration. The system is completely free of liquid cryogens for both sample cooling and magnet cool-down and operation. Software enables the system to conduct a full characterization of the temperature, magnetic field, and field angle dependence of the critical current of a sample without any user interaction. The system has successfully been used to measure a wide range of experimental and commercially-available superconducting wire samples sourced from different manufacturers across the full range of operating conditions. The system encapsulates significant advances in HTS magnet design and efficient cryogen-free cooling technologies together with the capability for routine and automated high-current electrical transport measurements at cryogenic temperatures. It will be of interest to both research scientists investigating superconductor behavior and commercial wire manufacturers seeking to accurately characterize the performance of their product under all desired operating conditions. PMID:25430124

  12. Effects of room-temperature tensile fatigue on critical current and n-value of IBAD-MOCVD YBa2Cu3O7-x /Hastelloy coated conductor

    NASA Astrophysics Data System (ADS)

    Rogers, Samuel; Kan Chan, Wan; Schwartz, Justin

    2016-08-01

    REBa2Cu3O7-x (REBCO) coated conductors potentially enable a multitude of superconducting applications, over a wide range of operating temperatures and magnetic fields, including high-field magnets, energy storage devices, motors, generators, and power transmission systems (Zhang et al 2013 IEEE Trans. Appl. Supercond. 23 5700704). Many of these are AC applications and thus the fatigue properties may be limiting (Vincent et al 2013 IEEE Trans. Appl. Supercond. 23 5700805). Previous electromechanical studies have determined the performance of REBCO conductors under single cycle loads (Barth et al 2015 Supercond. Sci. Technol. 28 045011), but an understanding of the fatigue properties is lacking. Here the fatigue behavior of commercial ion beam assisted deposition-metal organic chemical vapor deposition REBCO conductors on Hastelloy substrates is reported for axial tensile strains up to 0.5% and up to 100 000 cycles. Failure mechanisms are investigated via microstructural studies. Results show that REBCO conductors retained I c(ɛ)/I c0 = 0.9 for 10 000 cycles at ɛ = 0.35% and ɛ = 0.45% strain, and ɛ = 0.5% for 100 cycles. The main cause of fatigue degradation in REBCO conductors is crack propagation that initiates at the slitting defects that result from the manufacturing process.

  13. buffer Layer Growth, the Thickness Dependence of Jc in Coated Conductors, Local Identification of Current Limiting Mechanisms and Participation in the Wire Development Group

    SciTech Connect

    Larbalestier, David; Hellstron, Eric; Abraimov, Dmytro

    2011-12-17

    The primary thrusts of our work were to provide critical understanding of how best to enhance the current-carrying capacity of coated conductors. These include the deconstruction of Jc as a function of fim thickness, the growth of in situ films incorporating strong pinning centers and the use of a suite of position-sensitive tools that enable location and analysis of key areas where current-limiting occurs.

  14. Reel-to-reel deposition of epitaxial double-sided MgO buffer layers for coated conductors

    NASA Astrophysics Data System (ADS)

    Xue, Yan; Xiong, Jie; Zhang, Yahui; Zhang, Fei; Zhao, Rui-Peng; Hui, Wang; Wang, Quiling; Cheng, Guo; Zhao, Xiao-Hui; Tao, Bo-Wan

    2016-06-01

    We have successfully employed a double-sided process to deposit MgO buffer layers on both sides of amorphous Y2O3 surface for double-sided YBa2Cu3O7-δ (YBCO) coated conductors (CCs) for the first time, the structure of which is of great prospect to improve the performance and cut the production cost. The biaxial textures of MgO buffer layer are noticeably affected by the ion energy and film thickness, which is demonstrated by X-ray diffraction. The best biaxial texture of double-sided MgO films shows ω-scan of (002) MgO and Φ-scan of (220) MgO yield full width at half maximum values of 4° and 7.8° for one side, respectively, as well as 3.5° and 6.7° for the other side. The subsequent double-sided YBCO films are deposited on the as-prepared MgO template with entire critical current of over 300 A/cm for both sides.

  15. Much simplified ion-beam assisted deposition-TiN template for high-performance coated conductors

    NASA Astrophysics Data System (ADS)

    Xiong, J.; Matias, V.; Wang, H.; Zhai, J. Y.; Maiorov, B.; Trugman, D.; Tao, B. W.; Li, Y. R.; Jia, Q. X.

    2010-10-01

    A much simplified template, i.e., two nonsuperconducting layers between the superconducting YBa2Cu3O7-δ (YBCO) and the polycrystalline metal substrate, has been developed for high-performance coated conductors by using biaxially aligned TiN as a seed layer. A combination of a thin TiN (˜10 nm by ion-beam assisted deposition) layer and an epitaxial buffer LaMnO3 layer (˜120 nm) allows us to grow epitaxial YBCO films with values of full width at half-maximum around 3.5° and 1.7° for the ϕ-scan of (103) and rocking curve of (005) YBCO, respectively. The YBCO films grown on electropolished polycrystalline Hastelloy using this two-layer template exhibited a superconducting transition temperature of 89.5 K, a critical current density of 1.2 MA/cm2 at 75.5 K, and an α value (proportional factor of critical current density Jc˜H-α) of around 0.33, indicating a high density of pinning centers and an absence of weak links.

  16. Temperature and Magnetic Field Dependence of Critical Currents in YBCO Coated Conductors with Processing-Induced Variations in Pinning Properties

    SciTech Connect

    Gapud, Albert Agcaoili; Feenstra, Roeland; Christen, David K; Thompson, James R; Holesinger, T. G.

    2005-01-01

    Several applications of high-temperature super-conducting wire require high currents at intermediate magnetic fields B and over a range of orientations; however, such conditions are at present achievable only at low temperatures (-30 K). The goal of this study is to determine the feasibility of higher operating temperatures for these applications by investigating temperature dependent, low- and high-field pinning properties of YBCO coated conductor samples. The YBCO films were grown on RABiTS templates by a PVD ex situ BaF{sub 2} process. Variations in pinning properties were induced by introducing excess yttrium (Y) in the precursor and controllably increasing the growth rate. The main result is a more uniform dependence of J{sub c} over all orientations of B, along with high irreversibility field B{sub irr} and high critical current densities J{sub c}. Results also show that for films with various pinning properties and processed under different conditions the self-field J{sub c} at 77 K is an effective indicator of performance in the temperatures and fields of interest.

  17. Biaxially textured copper and copper iron alloy substrates for use in YBa2Cu3O7-x coated conductors

    NASA Astrophysics Data System (ADS)

    Varanasi, Chakrapani V.; Barnes, Paul N.; Yust, Nicholas A.

    2006-01-01

    Copper and Cu-Fe (Fe ~2.35 wt%) alloy substrates were thermo-mechanically processed and the biaxial texture development, magnetic properties, yield strength, and electrical resistivity were studied and compared to determine their suitability as substrates for high-temperature superconducting coated conductor applications. Average full width half maximum (FWHM) of 5.5° in Phi scans (in-plane alignment), and 6.6° in omega scans (out-of-plane alignment) was obtained in copper samples. Cu-Fe samples showed 5.9° FWHM in Phi scans and 5.9° in omega scans. Even with the presence of 2.35% Fe in the Cu-alloy, the saturation magnetization (Msat) value was found to be 4.27 emu g-1 at 5 K, which is less than in Ni samples by an order of magnitude and comparable to that of Ni-9 at.% W substrates. The yield strength of the annealed Cu-Fe alloy substrate was found to be at least two times higher than that of similarly annealed copper substrates. The electrical resistivity of Cu-Fe alloy was found to be an order of magnitude higher than that of pure copper at 77 K.

  18. Development of an RGB color analysis method for controlling uniformity in a long-length GdBCO coated conductor

    NASA Astrophysics Data System (ADS)

    Kim, Tae-Jin; Lee, Jae-Hun; Lee, Yu-Ri; Moon, Seung-Hyun

    2015-12-01

    Reactive co-evaporation-deposition and reaction (RCE-DR) is a very productive GdBa2Cu3O7-x (GdBCO) coated conductor (CC) fabrication process, which involves the fast phase conversion of an amorphous film formed by co-evaporation of three metal sources, Gd, Ba and Cu, and thus reduces the time and cost for fabrication of a GdBCO CC. We routinely use quartz crystal microbalance (QCM) to measure and control the evaporation rates of each metal source to keep a constant nominal composition of the superconducting (SC) layer. However, in the case of kilometre long GdBCO CC fabrication, evaporation rates measured by QCM do not exactly reflect deposition rates onto the substrate as source levels decrease, and thus an RGB color analysis method for quality control is designed. With this RGB color analysis method, it is possible to measure the composition of the converted SC layer very close to the actual composition, even in real time. We set up the RGB color analysis program by establishing a database, where RGB color values are matched to composition of the SC layer, and as a result of applying the program to the RCE-DR process, could fabricate high quality GdBCO CC with average critical current of 561 A cm-1 and 95% uniformity along a 1 km length.

  19. Reel-to-reel fabrication of meter-long YBCO coated conductor

    NASA Astrophysics Data System (ADS)

    Yang, J.; Zhang, H.; Wang, S. M.; Lin, C. G.; Shi, D. Q.; Dou, S. X.

    2011-04-01

    YBa 2Cu 3O 7-δ (YBCO) superconductors were coated on the CeO 2/YSZ/Y 2O 3 buffered Ni-5at%W tapes by a reel-to-reel pulsed laser deposition (PLD). The process of a multi-layer deposition of YBCO film was explored. X-ray diffraction texture measurements showed good both in-plane and out of plane crystalline orientations in YBCO films. The average values calculated at a full width at half maximum (FWHM) of the peaks from phi-scans ( φ) and omega ( ω) scans for one meter-long YBCO tape were 7.49° and 4.71°, respectively. The critical current ( Ic) was over 200 A/cm-width at 77 K and under self-field for meter-long YBCO tape. The critical transition temperature of the YBCO tape was typically as 90.1 K with 0.5 K transition widths.

  20. Uniform trapped fields produced by stacks of HTS coated conductor tape

    NASA Astrophysics Data System (ADS)

    Mitchell-Williams, T. B.; Baskys, A.; Hopkins, S. C.; Kalitka, V.; Molodyk, A.; Glowacki, B. A.; Patel, A.

    2016-08-01

    The trapped magnetic field profile of stacks of GdBa2Cu3O7-x superconducting tape was investigated. Angled stacks of superconducting tape were magnetized and found to produce very uniform trapped field profiles. The angled stacks were made of 12 mm × 24 mm solder coated tape pieces and were bonded together following a brief consolidation heat treatment. Layering multiple stacks together and adding a ferromagnetic plate beneath the samples were both found to enhance the magnitude and uniformity of the trapped field profiles. Stationary and time-dependent critical state finite element models were also developed to complement the experimental results and investigate the magnetization process. The size and shapes possible with the angled stacks make them attractive for applications requiring uniform magnetic fields over larger areas than can be achieved with existing bulk rings or tape annuli.

  1. Uniform trapped fields produced by stacks of HTS coated conductor tape

    NASA Astrophysics Data System (ADS)

    Mitchell-Williams, T. B.; Baskys, A.; Hopkins, S. C.; Kalitka, V.; Molodyk, A.; Glowacki, B. A.; Patel, A.

    2016-08-01

    The trapped magnetic field profile of stacks of GdBa2Cu3O7‑x superconducting tape was investigated. Angled stacks of superconducting tape were magnetized and found to produce very uniform trapped field profiles. The angled stacks were made of 12 mm × 24 mm solder coated tape pieces and were bonded together following a brief consolidation heat treatment. Layering multiple stacks together and adding a ferromagnetic plate beneath the samples were both found to enhance the magnitude and uniformity of the trapped field profiles. Stationary and time-dependent critical state finite element models were also developed to complement the experimental results and investigate the magnetization process. The size and shapes possible with the angled stacks make them attractive for applications requiring uniform magnetic fields over larger areas than can be achieved with existing bulk rings or tape annuli.

  2. High-Tc Coated Conductors - Performance of Meter-Long YBCO/IBAD Flexible Tapes

    SciTech Connect

    Foltyn, S.R.; Arendt, P.N.; Dowden, P.C.; DePaula, R.F.; Groves J.R.; Coulter, J.Y.; Jia, Q.; Maley, M.P.; Peterson, D.E.

    1998-09-13

    One meter long tapes based on 50-100 {micro}m thick by 1 cm wide nickel alloy substrates have been coated in a continuous process with a textured yttria-stabilized zirconia layer by ion beam-assisted deposition, followed by a 1-2 {micro}m thick layer of YBCO by pulsed laser deposition. The best result to date is a tape with a critical current (I{sub c}) at 75 K of 96 A over an 87 cm measurement length. The overall critical current density and engineering current density are 1 MA/cm{sup 2} and 10 kA/cm{sup 2}, respectively. Using a special probe, individual I-V curves were generated for each centimeter of tape length in order to investigate longitudinal uniformity of the transport properties: the highest and lowest I{sub c} values fall within a range of {+-}25%.

  3. Solution Deposition Approaches To Coated Conductor Fabrication on Biaxially Textured Ni-W Alloy Substrates

    SciTech Connect

    Sathyamurthy, S.

    2001-06-20

    Sol-gel processing of La{sub 2}Zr{sub 2}O{sub 7} (LZO) was used to process buffer layers on biaxially textured Ni-3 at.%W substrates. A reel-to-reel continuous dip-coating unit was used to deposit the solution buffers. Epitaxial LZO films have been obtained through continuous processing on Ni-3 at.%W substrates with strong texture and uniform microstructure. The carbon content in these films were analyzed using proton resonance Rutherford Backscattering (RBS). The process parameters have been modified so as to study the effect of the carbon content in these films towards further growth of YBCO films with better properties. The LZO buffers were used as seed layers for RABiTS with the architecture of CeO{sub 2}/YSZ/LZO/Ni-3 at.%W, and YBCO films with critical current density (J{sub c}) of 1.9 MA/cm{sup 2} at 77K in self-field, and a J{sub c} of 0.34 MA/cm{sup 2} at 0.5 T, have been obtained.

  4. High-Tc Superconducting Thin- and Thick-Film-Based Coated Conductors for Energy Applications

    SciTech Connect

    Cantoni, Claudia; Goyal, Amit

    2010-01-01

    Although the first epitaxial films of YBCO with high Tc were grown nearly 20 years ago, the understanding and control of the nanostructures responsible for the dissipation-free electrical current transport in high temperature superconductors (HTS) is quite recent. In the last six to seven years, major advances have occurred in the fundamental investigation of low angle grain boundaries, flux-pinning phenomena, growth mode, and atomic-level defect structures of HTS epitaxial films. As a consequence, it has been possible to map and even engineer to some extent the performance of HTS coatings in large regions of the operating H, T, J phase space. With such progress, the future of high temperature superconducting wires looks increasingly promising despite the tremendous challenges offered by these brittle and anisotropic materials. Nevertheless, further performance improvements are necessary for the superconducting technology to become cost-competitive against copper wires and ultimately succeed in revolutionizing the transmission of electricity. This can be achieved by further diminishing the gap between theoretical and experimental values of the critical current density Jc, and/or increasing the thickness of the superconductive layer as much as possible without degrading performance. In addition, further progress in controlling extrinsic and/or intrinsic nano-sized defects within the films is necessary to significantly reduce the anisotropic response of HTS and obtain a nearly constant dependence of the critical current on the magnetic field orientation, which is considered crucial for power applications. This chapter is a review of the challenges still present in the area of superconducting film processing for HTS wires and the approaches currently employed to address them.

  5. On-line characterization of YBCO coated conductors using Raman spectroscopy methods.

    SciTech Connect

    Maroni, V. A.; Reeves, J. L.; Schwab, G.; Chemical Engineering; SuperPower, Inc.

    2007-04-01

    The use of Raman spectroscopy for on-line monitoring of the production of superconducting YBa2Cu3O6+X (YBCO) thin films on long-length metal tapes coated with textured buffer layers is reported for the first time. A methodology is described for obtaining Raman spectra of YBCO on moving tape exiting a metal-organic-chemical-vapor-deposition (MOCVD) enclosure. After baseline correction, the spectra recorded in this way show the expected phonons of the specific YBCO crystal orientation required for high supercurrent transport, as well as phonons of non-superconducting second-phase impurities when present. It is also possible to distinguish YBCO films that are properly textured from films having domains of misoriented YBCO grains. An investigation of the need for focus control on moving tape indicated that focusing of the laser on the surface of the highly reflective YBCO films exiting the MOCVD enclosure tends to produce aberrant photon bursts that swamp the Raman spectrum. These photon bursts are very likely a consequence of optical speckle effects induced by a combination of surface roughness, crystallographic texture, and/or local strain within the small grain microstructure of the YBCO film. Maintaining a slightly out-of-focus condition provides the best signal-to-noise ratio in terms of the obtained Raman spectra. In addition to examining moving tape at the post-MOCVD stage, Raman spectra of the film surface can also be recorded after the oxygen anneal performed to bring the YBCO to the optimum superconducting state. Consideration is given to data processing methods that could be adapted to the on-line Raman spectra to allow the tagging of out-of-specification tape segments and, at a more advanced level, feedback control to the MOCVD process.

  6. A simple MOD method to grow a single buffer layer of Ce 0.8Gd 0.2O 1.9 (CGO) for coated conductors

    NASA Astrophysics Data System (ADS)

    Liu, Min; Shi, Dongqi; Suo, Hongli; Ye, Shuai; Zhao, Yue; Zhu, Yonghua; Li, Qi; Wang, Lin; Jihyun, Ahn; Zhou, Meiling

    2009-03-01

    A single Ce 0.8Gd 0.2O 1.9 (CGO) buffer layer was successfully grown on the home-made textured Ni-5 at.%W (Ni-5W) substrates for YBCO coated conductors by a simple metal-organic deposition (MOD) technique. The precursor solution was prepared using a newly developed process and only contained common metal-organic salts of both Ce and Gd dissolved into a propionic acid solvent. The precursor solution at 0.4 M concentration was spin coated on short samples of Ni-5W substrates and heat-treated at 1100 °C in a mixture gas of 5% H 2 in Ar for an hour. X-ray studies indicated that the CGO films had good out-of-plane and in-plane textures with full-width-half-maximum values of 4.18° and 6.19°, respectively. Atomic force microscope (AFM) investigations of the CGO films revealed that most of the grain boundary grooves on the Ni-5W surface were found to be well covered by CGO layers, which had a fairly dense and smooth microstructure without cracks and porosity. These results indicate that our MOD technique is very promising for further development of single buffer layer architecture for YBCO coated conductors, due to its low cost and simple process.

  7. Magnetisation and field quality of a cosine-theta dipole magnet wound with coated conductors for rotating gantry for hadron cancer therapy

    NASA Astrophysics Data System (ADS)

    Amemiya, Naoyuki; Sogabe, Yusuke; Sakashita, Masaki; Iwata, Yoshiyuki; Noda, Koji; Ogitsu, Toru; Ishii, Yusuke; Kurusu, Tsutomu

    2016-02-01

    Electromagnetic field analyses were carried out to study the influence of coated-conductor magnetisation, i.e. the screening (shielding) current, on the field quality of a dipole magnet in a rotating gantry for hadron cancer therapy. The analyses were made on the cross section of a cosine-theta dipole magnet in a rotating gantry for carbon ions, which generated 2.90 T of magnetic field. The temporal profile (temporal variation) of the magnet current was determined based on the actual excitation schemes of the magnets in the rotating gantry. The experimentally determined superconducting property of a coated conductor was considered, and we calculated the temporal evolutions of the current-density distributions in all the turns of coated conductors in the magnet. From the obtained current-density distributions, we calculated the multipole components of the magnetic field and evaluated the field quality of the magnet. The deviation in the dipole component from its designed value was up to approximately 25 mT, which was approximately 1% of the designed maximum dipole component. Its variation between repeated excitations was approximately 0.03%, and it drifted approximately 0.06% in 10 s. Some compensation schemes might be required to counteract such influence of magnetisation on the dipole component. Meanwhile, the higher multipole components were small, stable, and sufficiently reproducible for a magnet in rotating gantries, i.e. |b 3| ˜ 1.1 × 10-3 and |Δb 3| ˜ 0.2 × 10-3 in 10 s.

  8. Architecture for coated conductors

    DOEpatents

    Foltyn, Stephen R.; Arendt, Paul N.; Wang, Haiyan; Stan, Liliana

    2010-06-01

    Articles are provided including a base substrate having a layer of an oriented cubic oxide material with a rock-salt-like structure layer thereon, and, a layer of epitaxial titanium nitride upon the layer of an oriented cubic oxide material having a rock-salt-like structure. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of epitaxial titanium nitride or upon a intermediate buffer layer upon the layer of epitaxial titanium nitride.

  9. Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

    SciTech Connect

    Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-02

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the deposited AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.

  10. Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

    DOE PAGES

    Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-02

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the depositedmore » AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.« less

  11. Plasmonic three-dimensional transparent conductor based on Al-doped zinc oxide-coated nanostructured glass using atomic layer deposition.

    PubMed

    Malek, Gary A; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-29

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for designing plasmonic 3D transparent conductors. Transformation of the nonconducting 3D structure to a conducting porous surface network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electron-beam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO-coated glass surface along with the in-plane dimensions of the deposited AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to those of untextured two-dimensional AZO-coated glass substrates. In addition, transmittance measurements of the glass samples coated at various AZO thicknesses showed preservation of the transparent nature of each sample, and the AuNPs demonstrated enhanced light scattering as well as light-trapping capabilities.

  12. Plasmonic three-dimensional transparent conductor based on Al-doped zinc oxide-coated nanostructured glass using atomic layer deposition.

    PubMed

    Malek, Gary A; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-29

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for designing plasmonic 3D transparent conductors. Transformation of the nonconducting 3D structure to a conducting porous surface network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electron-beam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO-coated glass surface along with the in-plane dimensions of the deposited AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to those of untextured two-dimensional AZO-coated glass substrates. In addition, transmittance measurements of the glass samples coated at various AZO thicknesses showed preservation of the transparent nature of each sample, and the AuNPs demonstrated enhanced light scattering as well as light-trapping capabilities. PMID:25835062

  13. Conformal Coating of Three-Dimensional Nanostructures via Atomic Layer Deposition for Development of Advanced Energy Storage Devices and Plasmonic Transparent Conductors

    NASA Astrophysics Data System (ADS)

    Malek, Gary A.

    Due to the prodigious amount of electrical energy consumed throughout the world, there exists a great demand for new and improved methods of generating electrical energy in a clean and renewable manner as well as finding more effective ways to store it. This enormous task is of great interest to scientists and engineers, and much headway is being made by utilizing three-dimensional (3D) nanostructured materials. This work explores the application of two types of 3D nanostructured materials toward fabrication of advanced electrical energy storage and conversion devices. The first nanostructured material consists of vertically aligned carbon nanofibers. This three-dimensional structure is opaque, electrically conducting, and contains active sites along the outside of each fiber that are conducive to chemical reactions. Therefore, they make the perfect 3D conducting nanostructured substrate for advanced energy storage devices. In this work, the details for transforming vertically aligned carbon nanofiber arrays into core-shell structures via atomic layer deposition as well as into a mesoporous manganese oxide coated supercapacitor electrode are given. Another unique type of three-dimensional nanostructured substrate is nanotextured glass, which is transparent but non-conducting. Therefore, it can be converted to a 3D transparent conductor for possible application in photovoltaics if it can be conformally coated with a conducting material. This work details that transformation as well as the addition of plasmonic gold nanoparticles to complete the transition to a 3D plasmonic transparent conductor.

  14. Magnetic field orientation dependence of flux pinning in (Gd,Y)Ba2Cu3O7-x coated conductor with tilted lattice and nanostructures

    SciTech Connect

    Zhang, Yifei; Specht, Eliot D; Cantoni, Claudia; Christen, David K; Zuev, Yuri L; Goyal, Amit; Sinclair, J.; Thompson, James R; Aytug, Tolga; Paranthaman, Mariappan Parans; Chen, Y; Selvamanickam, V.

    2009-01-01

    The dependence of the critical current density (J{sub c}) on the orientation of an applied magnetic field was studied for a prototype (Gd,Y)Ba{sub 2}Cu{sub 3}O{sub 7?x} (GdYBCO) coated conductor fabricated by MOCVD on an IBAD-MgO template. Additional rare-earth cations (Y and Gd) and Zr were incorporated into the superconducting film to form (Y,Gd){sub 2}O{sub 3} and BaZrO{sub 3} nanoparticles extended nearly parallel to the a-b planes and to the c-axis, respectively, to enhance the flux pinning. In-field measurement of J{sub c} was carried out with electrical current flowing either along or perpendicular to the longitudinal axis of the tape, while a maximum Lorentz force configuration was always maintained. Details in the angular dependence of J{sub c} were related to the unique structure of the film, specifically the tilt in the GdYBCO lattice and the tilts in the extended (Y,Gd){sub 2}O{sub 3} and BaZrO{sub 3} nanoparticles. XRD and TEM were used to study the structure of the coated conductor. The effect of the misalignment between the external field H and the internal field B on the angular dependence of J{sub c} is discussed.

  15. Pursuing low joint resistivity in Cu-stabilized REBa2Cu3O δ coated conductor tapes by the ultrasonic weld-solder hybrid method

    NASA Astrophysics Data System (ADS)

    Shin, Hyung-Seop; Kim, Jong-min; Dedicatoria, Marlon J.

    2016-01-01

    Development of a coated conductor tape joint with good quality and low joint resistivity, R sj, in terms of transport and mechanical properties, was attempted by direct bonding at the interface of the Cu-Cu stabilizers in overlapped GdBCO CC tapes. In this study, we attempted to achieve a low R sj by introducing hybrid joining, soldering and ultrasonic welding (UW), and its mechanism was analyzed theoretically. Coated conductor tapes were experimentally joined using various methods of soldering, UW, and combinations of the two. As a result, a much lower R sj of about 57 nΩ · cm2 was obtained for RCE-DR-processed GdBCO CC tape joints using the hybrid joining method. The mechanical properties of the jointed CC tapes were also evaluated at room temperature and 77 K under self-field. Load-displacement curves of joined CC tapes followed the curve of the single CC tape. Critical current and joint resistance, R j, of hybrid-joined CC tape were retained after double bending at room temperature up to 20 mm bending diameter.

  16. Temperature dependence of critical current and transport current losses of 4 mm YBCO coated conductors manufactured using nonmagnetic substrate

    NASA Astrophysics Data System (ADS)

    Kvitkovic, J.; Hatwar, R.; Pamidi, S. V.; Fleshler, S.; Thieme, C.

    2015-12-01

    The temperature dependence of the critical current and AC losses were measured on American Superconductor Corporation's (AMSC) second generation high temperature superconducting (2G HTS) wire produced by Rolling Assisted Biaxially Textured Substrate (RABiTS) and Metal Organic Deposition (MOD) process. Wires manufactured with two types of substrates were characterized. The magnetic substrate with composition Ni5a%W exhibits a magnetic signature and has non-negligible AC losses in AC power applications. A new nonmagnetic substrate with an alloy composition Ni9a%W has been developed by AMSC to address the AC losses in 2G HTS. The data presented show that the performance of the new conductor is identical to the conductor with magnetic substrate in terms of critical current density. The data on AC losses demonstrate the absence of ferromagnetic loss component in the new conductor and significantly reduced AC losses at low to moderate values of I/Ic. The reduced losses will translate into reduced capital costs and lower operating costs of superconducting electrical devices for AC applications.

  17. Growth of epitaxial Y 2O 3 buffer layers on biaxially textured Ni-W substrates for YBCO coated conductors by MOD approach

    NASA Astrophysics Data System (ADS)

    Bhuiyan, M. S.; Paranthaman, M.; Kang, S.; Lee, D. F.; Salama, K.

    2005-06-01

    We have grown epitaxial Y 2O 3 buffer layers on biaxially textured Ni-W substrates for YBCO coated conductors using a newly developed metal organic decomposition (MOD) approach. Y 2O 3 precursor solution of 0.25 M concentration was spin coated on short samples of Ni-3 at.%W (Ni-W) substrates and heat-treated at 1150 °C in a gas mixture of Ar-4% H 2 for an hour. Detailed X-ray studies indicate that Y 2O 3 films have good out-of-plane and in-plane textures with full-width-half-maximum values of 6.22° and 7.51°, respectively. SEM and AFM investigations of Y 2O 3 films reveal a fairly dense and smooth microstructure without cracks and porosity. Highly textured YSZ barrier layers and CeO 2 cap layers were deposited on MOD Y 2O 3-buffered Ni-W substrates using rf-magnetron sputtering. Pulsed laser deposition was used to grow YBCO films on these substrates. A critical current, Jc, of about 1.21 MA/cm 2 at 77 K and self-field was obtained on YBCO (PLD)/CeO 2 (sputtered)/YSZ (sputtered)/Y 2O 3 (spin-coated)/Ni-W.

  18. MOD approach for the growth of epitaxial CeO2 buffer layers on biaxially textured Ni W substrates for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Bhuiyan, M. S.; Paranthaman, M.; Sathyamurthy, S.; Aytug, T.; Kang, S.; Lee, D. F.; Goyal, A.; Payzant, E. A.; Salama, K.

    2003-11-01

    We have grown epitaxial CeO2 buffer layers on biaxially textured Ni-W substrates for YBCO coated conductors using a newly developed metal organic decomposition (MOD) approach. Precursor solution of 0.25 M concentration was spin coated on short samples of Ni-3 at%W (Ni-W) substrates and heat-treated at 1100 °C in a gas mixture of Ar-4%H2 for 15 min. Detailed x-ray studies indicate that CeO2 films have good out-of-plane and in-plane textures with full-width-half-maximum values of 5.8° and 7.5°, respectively. High temperature in situ XRD studies show that the nucleation of CeO2 films starts at 600 °C and the growth completes within 5 min when heated at 1100 °C. SEM and AFM investigations of CeO2 films reveal a fairly dense microstructure without cracks and porosity. Highly textured YSZ barrier layers and CeO2 cap layers were deposited on MOD CeO2-buffered Ni-W substrates using rf-magnetron sputtering. Pulsed laser deposition (PLD) was used to grow YBCO films on these substrates. A critical current, Jc, of about 1.5 MA cm-2 at 77 K and self-field was obtained on YBCO (PLD)/CeO2 (sputtered)/YSZ (sputtered)/CeO2 (spin-coated)/Ni-W.

  19. ENSYSTROB - Design, manufacturing and test of a 3-phase resistive fault current limiter based on coated conductors for medium voltage application

    NASA Astrophysics Data System (ADS)

    Elschner, S.; Kudymow, A.; Brand, J.; Fink, S.; Goldacker, W.; Grilli, F.; Noe, M.; Vojenciak, M.; Hobl, A.; Bludau, M.; Jänke, C.; Krämer, S.; Bock, J.

    2012-11-01

    Within the German project ENSYSTROB a 3-phase resistive fault current limiter for medium voltage applications (12 kV, 533 Arms) was designed, built, tested and installed in the grid for a one year’s field test. The superconducting modules are made of YBCO coated conductors and replace the modules of an already successfully tested limiter on the basis of BSCCO 2212 bulk material. The components are multifilar spirals equipped with pairs of 12 mm wide YBCO tapes. The single components were characterized with respect to critical current, AC losses and limitation behavior under all possible operation conditions. The finally mounted limiter was successfully tested with respect to high voltage and limitation according to the standards of the customer. It is now installed and operating in its field test location. Finally we give a first comparison of both materials with respect to the different operational aspects.

  20. Magnetic and structural characterization of inkjet-printed TFAYBa2Cu3O7-x/MODCZO/ABADYSZ/SS coated conductors

    NASA Astrophysics Data System (ADS)

    Bartolomé, E.; Vlad, V. R.; Calleja, A.; Aklalouch, M.; Guzmán, R.; Arbiol, J.; Granados, X.; Palau, A.; Obradors, X.; Puig, T.; Usoskin, A.

    2013-12-01

    The superconductor industry is demanding new methodologies to manufacture km-long, high quality coated conductors at high growth rates, using cost-effective, scalable processes. We report on the fabrication by an all-chemical deposition method of highly textured, thick (0.9 μm) inkjet-printed YBCO films, using a Ce0.9Zr0.1O2 (CZO) capping layer deposited by MOD, on top of robust, buffered ABADYSZ/SS substrates. Thinner, 0.25 μm spin-coated YBCO films were also analyzed for comparison. The structural study performed by x-ray diffraction, optical, AFM, SEM and TEM microscopy demonstrates the success of the capping layer for enhancing the planarity of the as-received tape and obtaining highly homogeneous and well-textured YBCO films. DC magnetometry granularity analysis was used to determine the mean superconducting grain diameter, ˜2.5 μm, and the intra- and intergranular critical current densities of the coated conductors (CCs). For the thin, spin-coated sample, high self-field intragrain critical currents were measured ({J}_{{c}}^{{G}}=4 0, 3.3 MA cm-2 at 5, 77 K). For the thick, inkjet-printed tape {J}_{{c}}^{{G}} was reduced by ˜30%, but, notably, the percolative critical current, {J}_{{c}}^{{GB}}=1 2.5~{MA}~{{cm}}^{-2}, was only ˜10% smaller at 5 K, thanks to good preservation of the texture. At 77 K, {J}_{{c}}^{{GB}}=1.3~{MA}~{{cm}}^{-2} was achieved, implying a critical current of Ic = 117 A/cm-width. AC susceptibility measurements allowed us to demonstrate the high homogeneity of the fabricated CCs, and investigate the magnetic vortex-pinning phase diagram. Remarkably, the thick, inkjet-printed sample showed comparable irreversibility line (IL) and activation energy for thermal depinning, Ue(H), to the thin sample. The present results open new perspectives for the fabrication of high quality-to-cost ratio, all-chemical CCs with yet higher Ic values by inkjet printing multideposition of thicker YBCO layers.

  1. Conductor-polymer composite electrode materials

    DOEpatents

    Ginley, D.S.; Kurtz, S.R.; Smyrl, W.H.; Zeigler, J.M.

    1984-06-13

    A conductive composite material useful as an electrode, comprises a conductor and an organic polymer which is reversibly electrochemically dopable to change its electrical conductivity. Said polymer continuously surrounds the conductor in intimate electrical contact therewith and is prepared by electrochemical growth on said conductor or by reaction of its corresponding monomer(s) on said conductor which has been pre-impregnated or pre-coated with an activator for said polymerization. Amount of the conductor is sufficient to render the resultant composite electrically conductive even when the polymer is in an undoped insulating state.

  2. Epitaxial Growth Of Y2O3 On Biaxially Textured Ni Tapes Using A Sol-Gel Process For YBCO Coated Conductors

    NASA Astrophysics Data System (ADS)

    Ciontea, L.; Ristoiu, T.; Suciu, R.-C.; Petrisor, T.

    2007-04-01

    A solution processing technique was used to deposit an epitaxial Y2O3 film on (001)[100] cube textured Ni tapes for YBa2Cu3Ox (YBCO) coated conductors manufacturing. The cube texture was developed in Ni by a conventional thermo-mechanical process. A precursor solution of yttrium 2-methoxyethoxide in 2-methoxyethanol was spin-coated on the Ni substrate. The as-deposited amorphous film was thermally treated at 1100°C in a flowing Ar+4%H2 gas mixture. The θ-2θ X-ray spectra revealed predominantly (001) reflections, indicating a high degree of out-of-plane orientation. Pole figures for the (222) Y2O3 reflections demonstrate a single in-plane texture. The out-of-plane and in-plane epitaxial relationship is [400]Y2O3//[200] Ni and [110]Y2O3//[100] Ni, respectively. The full-width-half-maximum (FWHM) of the ω-scans and φ-scans is 6° and 11°, respectively.

  3. Reel-to-reel continuous simultaneous double-sided deposition of highly textured CeO2 templates for YBa2Cu3O7-δ coated conductors

    NASA Astrophysics Data System (ADS)

    Xiong, J.; Tao, B. W.; Qin, W. F.; Tang, J. L.; Han, X.; Li, Y. R.

    2008-02-01

    A reel-to-reel system which allows simultaneous two-sided deposition of epitaxial CeO2 buffer layers on long length biaxially textured Ni-5 at.%W tape with direct current (dc) reactive magnetron sputtering is described. Deposition is accomplished through two opposite symmetrical sputtering guns with a radiation heater. Meter-long double-sided epitaxial CeO2 buffer layers have been produced for the first time on textured metal substrates in a run using a reel-to-reel process with a speed of about 1.2 m h-1. The CeO2 films were characterized by means of x-ray diffraction (XRD) and atomic force microscopy (AFM). The samples exhibited good epitaxial growth with the c-axis perpendicular to the substrate surface for both sides. Full width at half maximum (FWHM) values of the out-of-plane and in-plane orientation for both sides were 3.2° and 3.1°, 5.3° and 5.1°, respectively. AFM observations revealed a smooth, dense and crack-free surface morphology. In addition, x-ray scans have been performed as a function of length to determine the crystallographic consistency of the epitaxial CeO2 over the length. Subsequently anyttria-stabilized zirconia (YSZ) barrier and CeO2 cap layers were deposited to complete the CeO2/YSZ/CeO2 structure via the same process. Epitaxial YBa2Cu3O7-δ (YBCO) films grown by dc sputtering on the short prototype CeO2/YSZ/CeO2/NiW conductors yielded self-field critical current densities (Jc) as high as 1.3 MA cm-2 at 77 K. An Ic value of 113 A cm-1 was obtained for double-sided YBCO coated conductors.

  4. Effects of room-temperature tensile fatigue on critical current and n-value of IBAD–MOCVD YBa2Cu3O7‑x /Hastelloy coated conductor

    NASA Astrophysics Data System (ADS)

    Rogers, Samuel; Kan Chan, Wan; Schwartz, Justin

    2016-08-01

    REBa2Cu3O7‑x (REBCO) coated conductors potentially enable a multitude of superconducting applications, over a wide range of operating temperatures and magnetic fields, including high-field magnets, energy storage devices, motors, generators, and power transmission systems (Zhang et al 2013 IEEE Trans. Appl. Supercond. 23 5700704). Many of these are AC applications and thus the fatigue properties may be limiting (Vincent et al 2013 IEEE Trans. Appl. Supercond. 23 5700805). Previous electromechanical studies have determined the performance of REBCO conductors under single cycle loads (Barth et al 2015 Supercond. Sci. Technol. 28 045011), but an understanding of the fatigue properties is lacking. Here the fatigue behavior of commercial ion beam assisted deposition–metal organic chemical vapor deposition REBCO conductors on Hastelloy substrates is reported for axial tensile strains up to 0.5% and up to 100 000 cycles. Failure mechanisms are investigated via microstructural studies. Results show that REBCO conductors retained I c(ε)/I c0 = 0.9 for 10 000 cycles at ε = 0.35% and ε = 0.45% strain, and ε = 0.5% for 100 cycles. The main cause of fatigue degradation in REBCO conductors is crack propagation that initiates at the slitting defects that result from the manufacturing process.

  5. Development of cube textured Ni 5at.%W alloy substrates for YBCO coated conductor application using a powder metallurgy process

    NASA Astrophysics Data System (ADS)

    Kim, S.-S.; Tak, J.-S.; Bae, S.-Y.; Chung, J.-K.; Ahn, I.-S.; Kim, C.-J.; Kim, K.-W.; Cho, K.-K.

    2007-10-01

    In this paper, Ni-5at.%W alloy substrate for YBCO coated conductor was fabricated by a dry powder metallurgy process including powder compaction, cold isostatic pressing (CIP), cold rolling and annealing for recrystallization. Ni and W powders were ball-milled at this process for various times of 10, 30, 50 and 100 h in argon atmosphere. The rod-like Ni-W alloy compacts were sintered at 1150 °C for 1 h in 96%Ar-4%H2 atmosphere. The sintered rods were cold rolling into thin tape of 70-90 μm thickness with 5% reduction at each path. The Ni-W alloy tapes were annealed at 800-1200 °C in an atmosphere of 96%Ar-4%H2 mixing gas for the development of cube texture. The tape with the best properties of low surface roughness, small grain size and strong cube texture was obtained at the condition annealed at 1200 °C using ball-milled powder for 30 min. The W addition to Ni improved the mechanical properties by solid solution hardening and inhibited grain growth for annealing heat treatment. The tapes were characterized by X-ray pole-figure, optical microscopy (OM), scanning electron microscopy (SEM) and scanning probe microscopy (SPM).

  6. The influence of grain boundary I c on the macroscopic strain effect of I c in BHO-doped GdBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Usami, Takashi; Ichino, Yusuke; Yoshida, Yutaka; Sugano, Michinaka; Ibi, Akira; Izumi, Teruo

    2016-07-01

    The effect of strain in REBa2Cu3O y (REBCO: RE = Y, Gd, Sm, Eu) coated conductors (CCs) on the critical current (I c) is one of the most fundamental factors for superconducting coil applications because CCs experience a variety of stresses. In this study, we carried out bending tests and measured the peak strain and the strain sensitivity of I c (a-value) for GdBCO CCs at 77 K under self-field. These values were evaluated for pure GdBCO CCs and BaHfO3 BHO-doped GdBCO CCs, which had oxide buffer layers with varying in-plane grain alignments of the CeO2 top layer. As a result, the peak strains and a-values for the BHO-doped GdBCO CCs depended on the FWHM of the CeO2 220 reflection in the φ-scan profile (Δφ), and decreased monotonically with decreasing Δφ. On the other hand, the peak strain and a-value were nearly independent of Δφ in the pure-GdBCO CCs. The change in peak strains for the BHO-doped GdBCO CCs are discussed on the basis of the relative contribution of intra-grain I c and inter-grain I c to the macroscopic strain effect of I c in the CCs.

  7. Characterizing transport current defects in 1-cm-wide YBa[sub 2]Cu[sub 3]O[sub 7-delta] coated conductors.

    SciTech Connect

    Brown, G. W.; Hawley, M. E.; Peterson, E. J.; Coulter, J. Y.; Dowden, P. C.; Arendt, P. N.; Foltyn, S. R.; Mueller, F. M.

    2001-01-01

    We have used a low temperature magnetic imaging system to determine current pathways in 5 cm long 'good' and 'bad' regions of a 1-cm-wide YBa2Cu3O7-{delta} coated conductor. The good and bad regions were identified with 4 point probe measurements taken at 1 cm intervals along the tape length. The current density map from the good region showed the expected edge peaked structure, similar to that seen in previous work on high quality test samples grown on single crystal substrates. The structure was also consistent with theoretical understanding of thin film superconductors where demagnetizing effects are strong. The maps from the bad region showed that the current was primarily confined to the right half of the sample. The left half carried only a small current that reached saturation quickly. Effectively halving the sample width quantitatively explains the critical current measured in that section. Spatially resolved xray analysis with 1 mm resolution was used to further characterize the bad section and suggested an abnormally large amount of a-axis YBCO present. This may be the result of non-uniform heating leading to a low deposition temperature in that area.

  8. Experimental measurement of characteristic Ic (ɛ, θ, B) response in GdBa2Cu3Oδ coated conductor tapes under low magnetic field at 77 K

    NASA Astrophysics Data System (ADS)

    Shin, Hyung-Seop; Dedicatoria, Marlon J.; Gorospe, Alking; Lee, Sang-Heon

    2015-03-01

    The continued development in the design technology of practical superconducting devices adopting high temperature superconductors tapes has led to a deeper understanding of their electromechanical behaviors. Rare-earth-barium-copper-oxide coated conductor (CC) tapes exhibit anisotropy of transport property (Ic) under magnetic field and its intrinsic strain effect is much significant depending on the orientation to the tape surface and the magnetic field intensity applied. Different experimental systems have already been developed to measure the relation of Ic with mechanical strain ɛ, magnetic field intensity B, and its angle of orientation, θ. However, few systems and instruments can measure these relationships simultaneously; either Ic-B-θ or Ic-ɛ-B is usually measured. In this study, a device which can measure these influences simultaneously based on a pair of permanent magnet systems was constructed and the characteristic responses of critical current Ic with strain, magnetic field, and its orientation with respect to the CC tape surface were investigated. The angular dependence of Ic with strain at 77 K in reactive co-evaporation by deposition and reaction GdBCO CC tapes has been measured using the permanent magnet system. The orientation angle of magnetic field with respect to the tape's surface was varied by rotating the rig fixture that holds a pair of permanent magnets. The strain sensitivity of Ic at different angles under low magnetic field was evaluated. As a result, a characteristic surface Ic (ɛ, θ, B) has been constructed as the characteristic response of Ic with strain and varying orientation under magnetic field.

  9. Mechanically reinforced {1 1 0} <1 1 0> textured Ag/Ni-alloys composite substrates for low-cost coated conductors

    NASA Astrophysics Data System (ADS)

    Suo, Hongli; Genoud, Jean-Yves; Caracino, Paola; Spreafico, Sergio; Schindl, Michael; Walker, Eric; Flükiger, René

    2002-08-01

    New, reinforced {1 1 0} <1 1 0> textured Ag/Ni-alloys composite ribbons were developed as possible substrates for coated conductors without any buffer layer. The texture quality and tensile strength were investigated. A new technique to bond the Ag and Ni or alloy layers through a Cu foil was presented. The Ag/Ni-alloys composite ribbons were fabricated by choosing proper sintering processing to bond the different layers followed by cold rolling and recrystallization. A thin Cu foil was intercalated between the initial Ag and Ni or alloy pieces to get a tough bond. A unique and stable {1 1 0} <1 1 0> annealing texture was obtained in 300 μm thick Ag/Ni composite ribbon after annealing. X-ray ODF analysis and EBSD measurements in the top Ag layer showed distribution of misorientation angles around 10-15°. A {1 1 0} <1 1 0> texture was also found in ribbons as thin as 50 μm, which cannot be obtained with pure Ag ribbons. A pronounced reduction of Ag amount was obtained in 60 μm thick Ag/NiCrV ribbons, with a textured Ag top layer being as thin as 7 μm. The amount of Ag was decreased by 75% compared to pure Ag ribbons of the same thickness. A strong enhancement of the mechanical properties was observed. The yield strength σ0.2 at 77 K was 220 MPa for Ag/NiCrV ribbons, i.e. considerably higher than the 30 MPa for pure Ag ribbons.

  10. Demonstration of High Current Density YBCO Coated Conductors on RE2O3-Buffered Ni Substrates with Two New Alternative Architectures

    SciTech Connect

    Beach, D.B.; Chirayil, T.G.; Christen, D.K.; Cui, X.; Feenstra, R.; Goyal, A.; Kroeger, D.M.; Lee, D.F.; Martin, P.M.; Mathis, J.E.; Morrell, J.S.; Norton, D.P.; Paranthaman, M.; Specht, E.D.; Verebelyi, D.T.

    1999-07-12

    In continuation of our effort to develop single buffer layer architectures for YBCO (YBa2Cu3O7-g) coated tape conductors, we have studied RE2O3 (RE = Y, and rare earths) as candidate materials. Three types of crystal structures including the preferred cubic phase are known for the rare earth oxides. High quality simple cubic RE2O3 buffer layers were grown epitaxiahy on {100}<001> textured Ni substrates using both reactive evaporation and sol-gel processing. Detailed X-ray studies have shown that the Y2O3, Eu2O3, Gd2O3, and Yb2O3 were grown with a single epitaxial orientation. SEM micrographs indicated that both e-beam and sol-gel grown films were dense, continuous and crack free. High Jc YBCO films were grown on RE2O3-buffered Ni substrates with sputtered cap layers. Two new alternative buffer layer architectures were developed. A high Jc of 1.8 MA/cm2 at 77 K and self-field was obtained on YBCO films with a layer sequence of YBCO (pulsed laser deposition)/Yb2O3 (sputtered)/Y2O3 (e-beam)/Ni. Also, a high Jc of over 1 MA/cm2 at 77 K and self-field was obtained on YBCO films with a layer sequence of YBCO (ex-situ BaF2 process)/CeO2 (sputtered)YSZ sputtered)/RE2O3 (sol-gel or e-beam)Ni. The performance of sol-gel grown buffers approached the quality of e-beam grown buffers.

  11. Buffer layers for coated conductors

    DOEpatents

    Stan, Liliana; Jia, Quanxi; Foltyn, Stephen R.

    2011-08-23

    A composite structure is provided including a base substrate, an IBAD oriented material upon the base substrate, and a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material. Additionally, an article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and a thick film upon the cubic metal oxide material. Finally, a superconducting article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and an yttrium barium copper oxide material upon the cubic metal oxide material.

  12. Microstructural investigation of phases and pinning properties in MBa2Cu3O7-x (M = Y and/or Gd) coated conductors produced by scale-up facilitie

    NASA Astrophysics Data System (ADS)

    Jin, Hye-Jin; Moon, Han-Kyoul; Yoon, Seokhyun; Jo, William; Kim, Kunsu; Kim, Miyoung; Ko, Rock-Kil; Jo, Young-Sik; Ha, Dong-Woo

    2016-03-01

    To expedite the commercialization of coated conductors, a robust stacking architecture of the wires must be developed and the performance of the critical currents improved. More importantly, the manufacturability, or large-scale delivery, and the capability of sustaining production at a high rate must be considered. The products of three companies, American Superconductor, Superpower Inc., and SuNAM Co., Ltd, were selected because these companies have announced commercial-grade production lines and delivered a significant amounts of wires to the open market that meet the standards demanded by power devices. X-ray diffraction patterns were used to verify the structural properties and the phase formation in the wires, and transmission electron microscopy with energy dispersive spectroscopy was used to investigate the microstructure and composition of the conductors. In addition, Raman scattering spectroscopy was used for the analysis of the phase formation and for the elucidation of secondary phases in the superconducting layers. The field dependence of the critical current was also studied to compare the transport characteristics under relatively low and medium magnetic field at 77 K and 60 K. Pinning forces were obtained from the field dependence of transport properties and pinning characteristics were investigated. The theoretical and experimental analyses were combined together using the Dew-Hughes formula to extract the scaling exponents and estimate the irreversibility lines of the fields. The results showed that the three conductors possess pinning mechanisms that originate from core pinning with a surface pinning geometry. It is remarkable that the wires discussed in this paper exhibit very similar pinning characteristics even though they have different characteristics in terms of chemical composition, microstructure, stacking architectures, and distribution of parasitic phases.

  13. Growth and superconducting properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} films on conductive SrRuO{sub 3} and LaNiO{sub 3} multilayers for coated conductor applications

    SciTech Connect

    Aytug, T.; Wu, J. Z.; Cantoni, C.; Verebelyi, D. T.; Specht, E. D.; Paranthaman, M.; Norton, D. P.; Christen, D. K.; Ericson, R. E.; Thomas, C. L.

    2000-02-07

    Conductive multilayers of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}/SrRuO{sub 3}/LaNiO{sub 3} (YBCO/SRO/LNO), YBCO/SRO, and YBCO/LNO were grown epitaxially on single-crystal LaAlO{sub 3} and SrTiO{sub 3} substrates. Property characterizations revealed that the YBCO films on SRO and SRO/LNO buffer structures have excellent structural and superconducting properties. The YBCO/LNO, however, suffers degradation in superconducting transition temperatures and critical current densities, despite a good crystalline structure. The SRO/LNO bilayer showed excellent electrical contact with YBCO. These results have demonstrated the structural and chemical compatibility of SRO/LNO multilayers with YBCO and their potential use as conductive buffer layers for YBCO-based coated conductors as well as for other high-temperature superconducting applications. (c) 2000 American Institute of Physics.

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

    SciTech Connect

    Pleva, E. F.; Mehrotra, V.; Schwenterly, S W

    2010-01-01

    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.

  15. Thunderclouds and Lightning Conductors

    ERIC Educational Resources Information Center

    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)

  16. The role of a-axis grains in the transition to the normal state of YBa{sub 2}Cu{sub 3}O{sub 7−δ} films and of 2G-coated conductors when induced by high electrical current densities

    SciTech Connect

    Bernstein, P. Harnois, C.; Mc Loughlin, C.; Noudem, J.; Thimont, Y.; Ferro, G.; Osorio, M. R.; Veira, J. A.; Vidal, D.; Vidal, F.

    2014-02-07

    The influence of surface defects, in particular of a-axis grains, on the transition to the normal state induced by high current densities in YBa{sub 2}Cu{sub 3}O{sub 7−δ} (YBCO) thin films and in a commercial 2G-coated conductor is investigated. For that purpose, the surface of the samples is observed by scanning electron microscopy and isothermal current-voltage curves are measured at different temperatures with pulsed currents up to the quenching value I*. The results show that the ratio of I* to the critical current is large if a-axis grains are not visible at the surface of the YBCO films, while it is much lower if the surface includes a-axis grains as this is the case for the coated conductor. The connection between the transition onset and the vortex dynamics, as well as the role of the a-axis grains in this process are discussed. The relation between the I* values obtained from thermal calculations and those resulting from vortex dynamics considerations is also discussed, as well as the possible consequences suggested by this work for the different applications of the coated conductors.

  17. Epitaxial growth of Ce 2Y 2O 7 buffer layers for YBa 2Cu 3O 7-δ coated conductors using reel-to-reel DC reactive sputtering

    NASA Astrophysics Data System (ADS)

    Fan, F.; Lu, Y. M.; Ying, L. L.; Liu, Z. Y.; Cai, C. B.; Hühne, R.; Holzapfel, B.

    2011-08-01

    Biaxially textured Ce 2Y 2O 7 (CYO) films were deposited on Ni-5at.%W (Ni-5W) tapes by a DC reactive sputtering technique in a reel-to-reel system. Subsequent YBa 2Cu 3O 7-δ (YBCO) films were prepared using pulsed laser deposition leading to a simplified coated conductor architecture of YBCO/CYO/Ni-5W. X-ray diffraction measurements revealed an epitaxial growth of the CYO buffer layer with a texture spread down to 2.2° and 4.7° for the out-of-plane and in-plane alignment, respectively. Microstructural investigations showed a dense, smooth and crack-free surface morphology for CYO film up to a thickness of 350 nm, implying an effective suppression of cracks due to the incorporation of Y in CeO 2. The superconducting transition temperature T c of about 90 K with a narrow transition of 0.8 K and the inductively measured critical current density J c of about 0.7 MA/cm 2 indicate the potential of the single CYO buffer layer.

  18. Vortex creep and critical current densities J c in a 2 μm thick SmBa2Cu3O7‑d coated conductor with mixed pinning centers grown by co-evaporation

    NASA Astrophysics Data System (ADS)

    Haberkorn, N.; Coulter, Y.; Condó, A. M.; Granell, P.; Golmar, F.; Ha, H. S.; Moon, S. H.

    2016-07-01

    We report the critical current densities J c and flux creep rates in a 2 μm thick SmBa2Cu3O7–δ coated conductor produced by co-evaporation. The sample presents strong pinning produced by correlated disorder (CD) (boundaries between growth islands, dislocations and twin boundaries) as well as random nanoparticles. Correlated pinning along the c-axis was evidenced due to the appearance of a large peak in the angular critical current, centered at H║c. The analysis of the critical current density J c (with the magnetic field applied parallel (H║c) and at 45° of the c-axis (H║45°)) indicates that CD assists pinning throughout the temperature range. For all temperatures and at both angles the in-field dependence of J c exhibits a power-law behavior. The contribution of CD drops when the field is rotated to intermediate angles between the c axis and a–b axis (i. e. H║45°), which derives in a reduction of the absolute J c value and poorer in-field dependences. The flux creep rate depends on the angle and its values remain approximately constant within the power-law regime. For H║c and H║45° and for magnetic fields lower than 20 kOe, the flux relaxation presents characterizing glassy exponents μ = 1.70 and μ = 1.32, respectively.

  19. Fabrication and characterization of La2Zr2O7 films on different buffer architectures for YBa2Cu3O7-δ coated conductors by RF magnetron sputtering.

    PubMed

    Xu, Da; Liu, Linfei; Xiao, Guina; Li, Yijie

    2013-02-27

    La2Zr2O7 (LZO) films were grown on different buffer architectures by radio frequency magnetron sputtering for the large-scale application of YBa2Cu3O7-x (YBCO)-coated conductors. The three different buffer architectures were cerium oxide (CeO2), yttria-stabilized zirconia (YSZ)/CeO2, and CeO2/YSZ/CeO2. The microstructure and surface morphology of the LZO film were studied by X-ray diffraction, optical microscopy, field emission scanning electron microscopy, and atomic force microscopy. The LZO films prepared on the CeO2, YSZ/CeO2, and CeO2/YSZ/CeO2 buffer architectures were preferentially c-axis-oriented and highly textured. The in-plane texture of LZO film on CeO2 single-buffer architecture was ∆ φ = 5.5° and the out-of-plane texture was ∆ ω = 3.4°. All the LZO films had very smooth surfaces, but LZO films grown on YSZ/CeO2 and CeO2/YSZ/CeO2 buffer architectures had cracks. The highly textured LZO film grown on CeO2-seed buffered NiW tape was suitable for the epitaxial growth of YBCO film with high currents.

  20. Vortex creep and critical current densities J c in a 2 μm thick SmBa2Cu3O7-d coated conductor with mixed pinning centers grown by co-evaporation

    NASA Astrophysics Data System (ADS)

    Haberkorn, N.; Coulter, Y.; Condó, A. M.; Granell, P.; Golmar, F.; Ha, H. S.; Moon, S. H.

    2016-07-01

    We report the critical current densities J c and flux creep rates in a 2 μm thick SmBa2Cu3O7-δ coated conductor produced by co-evaporation. The sample presents strong pinning produced by correlated disorder (CD) (boundaries between growth islands, dislocations and twin boundaries) as well as random nanoparticles. Correlated pinning along the c-axis was evidenced due to the appearance of a large peak in the angular critical current, centered at H║c. The analysis of the critical current density J c (with the magnetic field applied parallel (H║c) and at 45° of the c-axis (H║45°)) indicates that CD assists pinning throughout the temperature range. For all temperatures and at both angles the in-field dependence of J c exhibits a power-law behavior. The contribution of CD drops when the field is rotated to intermediate angles between the c axis and a-b axis (i. e. H║45°), which derives in a reduction of the absolute J c value and poorer in-field dependences. The flux creep rate depends on the angle and its values remain approximately constant within the power-law regime. For H║c and H║45° and for magnetic fields lower than 20 kOe, the flux relaxation presents characterizing glassy exponents μ = 1.70 and μ = 1.32, respectively.

  1. Coatings.

    ERIC Educational Resources Information Center

    Anderson, Dennis G.

    1989-01-01

    This review covers analytical techniques applicable to the examination of coatings, raw materials, and substrates upon which coatings are placed. Techniques include chemical and electrochemical methods, chromatography, spectroscopy, thermal analysis, microscopy, and miscellaneous techniques. (MVL)

  2. Experimental measurement of characteristic I(c) (ε, θ, B) response in GdBa2Cu3Oδ coated conductor tapes under low magnetic field at 77 K.

    PubMed

    Shin, Hyung-Seop; Dedicatoria, Marlon J; Gorospe, Alking; Lee, Sang-Heon

    2015-03-01

    The continued development in the design technology of practical superconducting devices adopting high temperature superconductors tapes has led to a deeper understanding of their electromechanical behaviors. Rare-earth-barium-copper-oxide coated conductor (CC) tapes exhibit anisotropy of transport property (Ic) under magnetic field and its intrinsic strain effect is much significant depending on the orientation to the tape surface and the magnetic field intensity applied. Different experimental systems have already been developed to measure the relation of Ic with mechanical strain ε, magnetic field intensity B, and its angle of orientation, θ. However, few systems and instruments can measure these relationships simultaneously; either Ic-B-θ or Ic-ε-B is usually measured. In this study, a device which can measure these influences simultaneously based on a pair of permanent magnet systems was constructed and the characteristic responses of critical current Ic with strain, magnetic field, and its orientation with respect to the CC tape surface were investigated. The angular dependence of Ic with strain at 77 K in reactive co-evaporation by deposition and reaction GdBCO CC tapes has been measured using the permanent magnet system. The orientation angle of magnetic field with respect to the tape's surface was varied by rotating the rig fixture that holds a pair of permanent magnets. The strain sensitivity of Ic at different angles under low magnetic field was evaluated. As a result, a characteristic surface Ic (ε, θ, B) has been constructed as the characteristic response of Ic with strain and varying orientation under magnetic field. PMID:25832245

  3. Depth profiling of the microwave surface resistance of high-J C GdBa2Cu3O7-δ coated conductors grown using the RCE-DR process

    NASA Astrophysics Data System (ADS)

    Yang, Woo, II; Jung, Ho Sang; Lee, Jae-Hun; Lee, Hunju; Moon, Seung-Hyun; Lee, Jung-Woo; Yoo, Sang-Im; Lee, Sang Young

    2016-10-01

    We study depth profiling of the microwave surface resistance (R S) of GdBa2Cu3O7-δ (GdBCO) coated conductors (CCs) grown using the reactive co-evaporation by deposition and reaction (RCE-DR) method, a method enabling extremely high deposition rate. GdBCO CCs with the critical current (I C) of more than 790 A cm-1 at 77 K in self-field are used for the study. The R S of the GdBCO CCs is measured at temperatures of 10-80 K using a 8.5 GHz TE011-mode rutile resonator, which is compared with that of YBa2Cu3O7-δ films and GdBCO films epitaxially grown on single crystal substrates. It turns out that there is significant inhomogeneity in the R S over the thickness of the GdBCO layer, with the R S value of the top part at 30 K being almost two times higher than the corresponding one of the bottom part. A transmission electron microscopy study reveals that Gd2O3 grains coexist with GdBCO grains with the average Gd2O3 grain sizes being ˜150 nm at the top and ˜100 nm at the bottom of the GdBCO layer. We relate the inhomogeneity in the R S of the GdBCO layer with the positional dependence of the Gd2O3 grain size, for which effects of the dielectric losses from the Gd2O3 grains on the measured R S of the GdBCO layer are considered. Our results imply that the critical current density, another important transport property of superconductors, could be inhomogeneous over the thickness of the GdBCO layer grown using the RCE-DR method.

  4. Experimental measurement of characteristic I(c) (ε, θ, B) response in GdBa2Cu3Oδ coated conductor tapes under low magnetic field at 77 K.

    PubMed

    Shin, Hyung-Seop; Dedicatoria, Marlon J; Gorospe, Alking; Lee, Sang-Heon

    2015-03-01

    The continued development in the design technology of practical superconducting devices adopting high temperature superconductors tapes has led to a deeper understanding of their electromechanical behaviors. Rare-earth-barium-copper-oxide coated conductor (CC) tapes exhibit anisotropy of transport property (Ic) under magnetic field and its intrinsic strain effect is much significant depending on the orientation to the tape surface and the magnetic field intensity applied. Different experimental systems have already been developed to measure the relation of Ic with mechanical strain ε, magnetic field intensity B, and its angle of orientation, θ. However, few systems and instruments can measure these relationships simultaneously; either Ic-B-θ or Ic-ε-B is usually measured. In this study, a device which can measure these influences simultaneously based on a pair of permanent magnet systems was constructed and the characteristic responses of critical current Ic with strain, magnetic field, and its orientation with respect to the CC tape surface were investigated. The angular dependence of Ic with strain at 77 K in reactive co-evaporation by deposition and reaction GdBCO CC tapes has been measured using the permanent magnet system. The orientation angle of magnetic field with respect to the tape's surface was varied by rotating the rig fixture that holds a pair of permanent magnets. The strain sensitivity of Ic at different angles under low magnetic field was evaluated. As a result, a characteristic surface Ic (ε, θ, B) has been constructed as the characteristic response of Ic with strain and varying orientation under magnetic field.

  5. Flat conductor cable applications

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1972-01-01

    Some of the numerous applications of flat conductor cable (FCC) systems are briefly described. Both government and commercial uses were considered, with applications designated as either aerospace, military, or commercial. The number and variety of ways in which FCC is being applied and considered for future designs are illustrated.

  6. Study on Quench Protection of HTS Coil Wound of YBCO Conductor

    NASA Astrophysics Data System (ADS)

    Fu, Youkun; Tsukamoto, Osami; Furuse, Mitsuho

    Recent progress of long YBCO coated conductors is remarkable and coils wound of YBCO conductors will be developed in near future. YBCO coated conductors that are made by deposition of thin YBCO film on high resistance metal substrates such as Hastelloy and nickel tapes are highly resistive when they are quenched. Therefore, measures for stabilization and quench protection are more important for YBCO conductors than for Bi/Ag sheathed tapes which have low resistive silver matrix. Though HTS conductors working at liquid nitrogen temperature are hard to be quenched, the conductors still have possibilities of quenches due to local defects for example. We studied necessary amount of copper stabilizer to protect the YBCO conductors in coils from damages caused by hot spots due to quenches. In the work we numerically calculated maximum hot spot temperature of a YBCO conductor quenched by a local disturbance during the sequence of quench detection and energy dump. In the analysis, necessary amounts of copper to keep the maximum hot spot temperature below a threshold are calculated. Based on the analysis, optimum conductor design is discussed to obtain safe and high current density conductors.

  7. Fast Ion Conductors

    NASA Astrophysics Data System (ADS)

    Chadwick, Alan V.

    Fast ion conductors, sometimes referred to as superionic conductors or solid electrolytes, are solids with ionic conductivities that are comparable to those found in molten salts and aqueous solutions of strong electrolytes, i.e., 10-2-10 S cm-1. Such materials have been known of for a very long time and some typical examples of the conductivity are shown in Fig. 1, along with sodium chloride as the archetypal normal ionic solid. Faraday [1] first noted the high conductivity of solid lead fluoride (PbF2) and silver sulphide (Ag2S) in the 1830s and silver iodide was known to be unusually high ionic conductor to the German physicists early in the 1900s. However, the materials were regarded as anomalous until the mid 1960s when they became the focus of intense interest to academics and technologists and they have remained at the forefront of materials research [2-4]. The academic aim is to understand the fundamental origin of fast ion behaviour and the technological goal is to utilize the properties in applications, particularly in energy applications such as the electrolyte membranes in solid-state batteries and fuel cells, and in electrochemical sensors. The last four decades has seen an expansion of the types of material that exhibit fast ion behaviour that now extends beyond simple binary ionic crystals to complex solids and even polymeric materials. Over this same period computer simulations of solids has also developed (in fact these methods and the interest in fast ion conductors were almost coincidental in their time of origin) and the techniques have played a key role in this area of research.

  8. Coated Conductors for the Magnetic Bearing Application

    NASA Astrophysics Data System (ADS)

    Sass, Felipe; Dias, Daniel Henrique Nogueira; Sotelo, Guilherme Gonçalves; Júnior, Rubens de Andrade

    The second generation (2G) of superconductor wires have been considered for several applications lately. This work presents a preliminary study of superconducting magnetic bearings (SMB) using 2G wires as passive levitators. A superconducting block using stacked 2G wires was built to evaluate the magnetic bearing behavior, thought levitation force measurements, when a permanent magnet cylinder approaches or moves away from the block. The superconducting block was compared with an YBCO bulk with nearly the same dimensions and the results show a promising potential for this application.

  9. Method for preparing a thick film conductor

    DOEpatents

    Nagesh, Voddarahalli K.; Fulrath, deceased, Richard M.

    1978-01-01

    A method for preparing a thick film conductor which comprises providing surface active glass particles, mixing the surface active glass particles with a thermally decomposable organometallic compound, for example, a silver resinate, and then decomposing the organometallic compound by heating, thereby chemically depositing metal on the glass particles. The glass particle mixture is applied to a suitable substrate either before or after the organometallic compound is thermally decomposed. The resulting system is then fired in an oxidizing atmosphere, providing a microstructure of glass particles substantially uniformly coated with metal.

  10. Conditioning flat conductors for flat conductor cable production

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Apparatus can straighten, anneal, clean, and a tension to stretch a cable one percent to assure uniform cross-sectional area. A conductor passes through temperature controlled distilled water and through a toroid coil. As The conductor enters the water, steam performs the cleaning action. Quenching and annealing also take place.

  11. 66. DETAIL OF LAUNCH CONDUCTOR AND ASSISTANT LAUNCH CONDUCTOR PANELS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    66. DETAIL OF LAUNCH CONDUCTOR AND ASSISTANT LAUNCH CONDUCTOR PANELS IN CONSOLE LOCATED CENTRALLY IN SLC-3E CONTROL ROOM. FROM LEFT TO RIGHT IN BACKGROUND: LAUNCH OPERATOR, LAUNCH ANALYST, AND FACILITIES PANELS. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

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

    SciTech Connect

    Matsuzaki, Y.; Hishinuma, M.

    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.

  13. Floating insulated conductors for heating subsurface formations

    DOEpatents

    Burns, David; Goodwin, Charles R.

    2014-07-29

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  14. Fluorite Ce0.8Sm0.2O2- δ porous layer coating to enhance the oxygen permeation behavior of a BaCo0.7Fe0.2Nb0.1O3- δ mixed conductor

    NASA Astrophysics Data System (ADS)

    Wang, Tai-he; Song, Wei-jia; Li, Rong; Zhen, Qiang

    2016-06-01

    Fluorite Ce0.8Sm0.2O2- δ (SDC) nanopowder with a crystallite size of 15 nm was synthesized by a co-precipitation method. An SDC porous layer was coated onto a BaCo0.7Fe0.2Nb0.1O3- δ (BCFN) mixed conductor to improve its oxygen transport behavior. The results show that the SDC-coated BCFN membrane exhibits a remarkably higher oxygen permeation flux ({J_{{O_2}}}) than the uncoated BCFN in the partial oxidation of coke oven gas (COG). The maximum {J_{{O_2}}} value of the SDC-coated BCFN is 18.28 mL·min-1·cm-2 under a COG/air flux of 177 mL·min-1/353 mL·min-1 at 875°C when the thickness of the BCFN membrane is 1 mm; this {J_{{O_2}}} value is 23% higher than that of the uncoated BCFN membrane. This enhancement is likely because of the higher oxygen ionic conductivity of SDC, which supplies oxygen vacancies and accelerates oxygen exchange on the membrane/coating layer/gas three-phase boundary.

  15. Intercalated graphite electrical conductors

    NASA Technical Reports Server (NTRS)

    Banks, B. A.

    1983-01-01

    For years NASA has wanted to reduce the weight of spacecraft and aircraft. Experiments are conducted to find a lightweight synthetic metal to replace copper. The subject of this paper, intercalated graphite, is such a material. Intercalated graphite is made by heating petroleum or coal to remove the hydrogen and to form more covalent bonds, thus increasing the molecular weight. The coal or petroleum eventually turns to pitch, which can then be drawn into a fiber. With continued heating the pitch-based fiber releases hydrogen and forms a carbon fiber. The carbon fiber, if heated sufficiently, becomes more organized in parallel layers of hexagonally arranged carbon atoms in the form of graphite. A conductor of intercalated graphite is potentially useful for spacecraft or aircraft applications because of its low weight.

  16. 35.4 T field generated using a layer-wound superconducting coil made of (RE)Ba2Cu3O7-x (RE = rare earth) coated conductor

    NASA Astrophysics Data System (ADS)

    Trociewitz, Ulf P.; Dalban-Canassy, Matthieu; Hannion, Muriel; Hilton, David K.; Jaroszynski, Jan; Noyes, Patrick; Viouchkov, Youri; Weijers, Hubertus W.; Larbalestier, David C.

    2011-11-01

    To explore the limits of layer wound (RE)Ba2Cu3O7-x (REBCO, RE = rare earth) coils in a high magnetic field environment >30 T, a series of small insert coils have been built and characterized in background fields. One of the coils repeatedly reached 35.4 T using a single ˜100 m length of REBCO tape wet wound with epoxy and nested in a 31 T background magnet. The coil was quenched safely several times without degradation. Contributing to the success of this coil was the introduction of a thin polyester film that surrounded the conductor. This approach introduces a weak circumferential plane in the coil pack that prevents conductor delamination that has caused degradation of several epoxy impregnated coils previously made by this and other groups.

  17. Flat conductor cable commercialization project

    NASA Technical Reports Server (NTRS)

    Hogarth, P.; Wadsworth, E.

    1977-01-01

    An undercarpet flat conductor cable and a baseboard flat conductor cable system were studied for commercialization. The undercarpet system is designed for use in office and commercial buildings. It employs a flat power cable, protected by a grounded metal shield, that terminates in receptacles mounted on the floor. It is designed to interface with a flat conductor cable telephone system. The baseboard system consists of a flat power cable mounted in a plastic raceway; both the raceway and the receptacles are mounted on the surface of the baseboard. It is designed primarily for use in residential buildings, particularly for renovation and concrete and masonry construction.

  18. 33 CFR 183.445 - Conductors: Protection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors: Protection. 183.445 Section 183.445 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Conductors: Protection. (a) Each conductor or group of conductors that passes through a bulkhead,...

  19. 33 CFR 183.445 - Conductors: Protection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Conductors: Protection. 183.445 Section 183.445 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Conductors: Protection. (a) Each conductor or group of conductors that passes through a bulkhead,...

  20. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage...

  1. Conductor for a fluid-cooled winding

    DOEpatents

    Kenney, Walter J.

    1983-01-01

    A conductor and method of making the conductor are provided for use in winding electrical coils which are cooled by a fluid communicating with the conductor. The conductor is cold worked through twisting and reshaping steps to form a generally rectangular cross section conductor having a plurality of helical cooling grooves extending axially of the conductor. The conductor configuration makes it suitable for a wide variety of winding applications and permits the use of simple strip insulation between turns and perforated sheet insulation between layers of the winding.

  2. Microstructure development and interface studies in thick film conductor systems

    NASA Astrophysics Data System (ADS)

    Nagesh, V. K.

    1980-03-01

    A thick film conductor system which used acid treated (.01N HCl) lead borosilicate glass particles with chemically coated metal (silver) film was developed. Using only 40 wt percent metal (silver), sheet resistivities as low as 45 milliohms/sq were obtained. Microstructure was studied. Effect on the acid treatment of the glass particles prior to the metal coating was analyzed. X-ray photoelectron spectra studies showed preferential leaching of lead and boron from the surface of the glass. Good bonding between silver film and the glass was attributed to the oxidation of silver in the presence of oxygen and H+ ions on the glass surface (from acid treatment) and subsequent diffusion of Ag+ into the glass to form a continuous chemical interface. A model to predict sheet resistivities of the new thick film conductors was developed.

  3. A lithium superionic conductor.

    PubMed

    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

  4. A lithium superionic conductor.

    PubMed

    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).

  5. High Temperature Protonic Conductors

    NASA Technical Reports Server (NTRS)

    Dynys, Fred; Berger, Marie-Helen; Sayir, Ali

    2007-01-01

    High Temperature Protonic Conductors (HTPC) with the perovskite structure are envisioned for electrochemical membrane applications such as H2 separation, H2 sensors and fuel cells. Successive membrane commercialization is dependent upon addressing issues with H2 permeation rate and environmental stability with CO2 and H2O. HTPC membranes are conventionally fabricated by solid-state sintering. Grain boundaries and the presence of intergranular second phases reduce the proton mobility by orders of magnitude than the bulk crystalline grain. To enhanced protonic mobility, alternative processing routes were evaluated. A laser melt modulation (LMM) process was utilized to fabricate bulk samples, while pulsed laser deposition (PLD) was utilized to fabricate thin film membranes . Sr3Ca(1+x)Nb(2-x)O9 and SrCe(1-x)Y(x)O3 bulk samples were fabricated by LMM. Thin film BaCe(0.85)Y(0.15)O3 membranes were fabricated by PLD on porous substrates. Electron microscopy with chemical mapping was done to characterize the resultant microstructures. High temperature protonic conduction was measured by impedance spectroscopy in wet air or H2 environments. The results demonstrate the advantage of thin film membranes to thick membranes but also reveal the negative impact of defects or nanoscale domains on protonic conductivity.

  6. n value and Jc distribution dependence of AC transport current losses in HTS conductors

    NASA Astrophysics Data System (ADS)

    Ogawa, Jun; Sawai, Yusuke; Nakayama, Haruki; Tsukamoto, Osami; Miyagi, Daisuke

    2004-01-01

    Compared with LTS materials, HTS materials have some peculiarities affecting AC loss characteristics of the conductors. We measured the AC transport current losses in YBCO thin film coated conductors and a Bi2223/Ag sheathed tape. Comparing the measured data with analytical calculations, the dependence of the AC transport current losses on the n value and critical current density distributions are studied. It is shown that, considering the n values and Jc distributions, the peculiarities in the HTS materials can be taken into consideration and the transport current losses in HTS conductors can be calculated by the same analytical method used for LTS.

  7. Zinc oxyfluoride transparent conductor

    SciTech Connect

    Gordon, R.G.

    1991-02-05

    Transparent, electrically conductive and infrared-reflective films of zinc oxyfluoride are produced by chemical vapor deposition from vapor mixtures of zinc, oxygen and fluorine-containing compounds. The substitution of fluorine for some of the oxygen in zinc oxide results in dramatic increases in the electrical conductivity. For example, diethyl zinc, ethyl alcohol and hexafluoropropene vapors are reacted over a glass surface at 400 C to form a visibly transparent, electrically conductive, infrared reflective and ultraviolet absorptive film of zinc oxyfluoride. Such films are useful in liquid crystal display devices, solar cells, electrochromic absorbers and reflectors, energy-conserving heat mirrors, and antistatic coatings. 8 figures.

  8. Zinc oxyfluoride transparent conductor

    DOEpatents

    Gordon, Roy G.

    1991-02-05

    Transparent, electrically conductive and infrared-reflective films of zinc oxyfluoride are produced by chemical vapor deposition from vapor mixtures of zinc, oxygen and fluorine-containing compounds. The substitution of fluorine for some of the oxygen in zinc oxide results in dramatic increases in the electrical conductivity. For example, diethyl zinc, ethyl alcohol and hexafluoropropene vapors are reacted over a glass surface at 400.degree. C. to form a visibly transparent, electrically conductive, infrared reflective and ultraviolet absorptive film of zinc oxyfluoride. Such films are useful in liquid crystal display devices, solar cells, electrochromic absorbers and reflectors, energy-conserving heat mirrors, and antistatic coatings.

  9. Transparent oxides forming conductor/insulator/conductor heterojunctions for photodetection

    NASA Astrophysics Data System (ADS)

    Ishii, Satoshi; Duy Dao, Thang; Chen, Kai; Nagao, Tadaaki

    2015-05-01

    Photoexcited hot electrons from conductors can be injected into the conduction bands of wide-bandgap materials, thus enabling the visible and near-infrared (NIR) photoactivities of light-harvesting devices. While metals have been dominantly used as conductors to excite hot electrons, we demonstrate that transparent conductive oxides (TCOs) can also be used for this purpose. Trilayer structures consisting of a thin dielectric layer sandwiched by TCOs show photoresponsiveness in UV, visible, as well as NIR wavelength range. As these trilayer structures are transparent, they can be used to monitor light without blocking it.

  10. Quartz antenna with hollow conductor

    DOEpatents

    Leung, Ka-Ngo; Benabou, Elie

    2002-01-01

    A radio frequency (RF) antenna for plasma ion sources is formed of a hollow metal conductor tube disposed within a glass tube. The hollow metal tubular conductor has an internal flow channel so that there will be no coolant leakage if the outer glass tube of the antenna breaks. A portion of the RF antenna is formed into a coil; the antenna is used for inductively coupling RF power to a plasma in an ion source chamber. The antenna is made by first inserting the metal tube inside the glass tube, and then forming the glass/metal composite tube into the desired coil shape.

  11. Conductor shears as iceberg encroaches

    SciTech Connect

    Not Available

    1984-10-01

    Operators in the Arctic regions must protect wellheads from encroaching icebergs and icepack sheets. Diverting ice masses and excavating large holes below scour depth is expensive. Now an alternate approach allows the conductor to shear, shuts in the well, and provides a method of re-entering the well. The new system has been successfully used by Mobil on two exploratory wells in the Hibernia field off eastern Canada. The wells used 18 3/4-in. wellheads rated at 10,000 psi with 36-in. conductor pipe. The performance of the system is discussed.

  12. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  13. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  14. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  15. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  16. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  17. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  18. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  19. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary... surges each conductor must not carry a current greater than that specified in Table 5 for the...

  20. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary... surges each conductor must not carry a current greater than that specified in Table 5 for the...

  1. Preparing the Conductor as Teacher

    ERIC Educational Resources Information Center

    Ulrich, Jerry

    2009-01-01

    While music is as old as humanity, conducting as a profession is relatively new. Although a nineteenth-century model has served as the template for the training of conductors, many undergraduate conducting students will spend their teaching careers working with inexperienced and/or amateur musicians. Additionally, the size of many ensembles in…

  2. 76 FR 69801 - Conductor Certification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... Federal Register on November 10, 2010. See 75 FR 69166. In the NPRM, FRA solicited public comment on the... (75 FR 69166, 69170 (Nov. 10, 2010)) and in the section-by-section analysis to this final rule: Under....105(c)(1)-(3), a railroad may test and evaluate its designated conductors under subpart B before...

  3. Flat conductor cable design, manufacture, and installation

    NASA Technical Reports Server (NTRS)

    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.

  4. Temperature limited heater utilizing non-ferromagnetic conductor

    DOEpatents

    Vinegar; Harold J. , Harris; Christopher Kelvin

    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. Method for making conductors for ferrite memory arrays. [from pre-formed metal conductors

    NASA Technical Reports Server (NTRS)

    Heckler, C. H.; Baba, P. D.; Bhiwandker, N. C. (Inventor)

    1974-01-01

    The ferrite memory arrays are made from pre-formed metal conductors for the ferrite arrays. The conductors are made by forming a thin sheet of a metallizing paste of metal alloy powder, drying the paste layer, bisque firing the dried sheet at a first temperature, and then punching the conductors from the fired sheet. During the bisque firing, the conductor sheet shrinks to 58 percent of its pre-fired volume and the alloy particles sinter together. The conductors are embedded in ferrite sheet material and finally fired at a second higher temperature during which firing the conductors shrink approximately the same degree as the ferrite material.

  6. Rapid doubling of the critical current of Yba{sub 2}Cu{sub 3}O{sub 7-{delta}} coated conductor for viable high-speed industrial processing.

    SciTech Connect

    Leroux, M.; Kihlstrom, K. J.; Holleis, S.; Rupich, M. W.; Sathyamurthy, S.; Fleshler, S.; Sheng, H. P.; Miller, D. J.; Eley, S.; Civale, L.; Kayani, A.; Niraula, P. M.; Welp, U.; Kwok, W. -K.

    2015-11-09

    We demonstrate that 3.5-MeV oxygen irradiation can markedly enhance the in-field critical current of commercial 2nd generation superconducting tapes with an exposure time of just one second per 0.8 cm2. The speed demonstrated here is now at the level required for an industrial reel-to-reel post-processing. The irradiation is made on production line samples through the protective silver coating and does not require any modification of the growth process. From TEM imaging, we identify small clusters as the main source of increased vortex pinning.

  7. Rapid doubling of the critical current of YBa{sub 2}Cu{sub 3}O{sub 7−δ} coated conductors for viable high-speed industrial processing

    SciTech Connect

    Leroux, M.; Welp, U.; Kwok, W.-K.; Kihlstrom, K. J.; Holleis, S.; Rupich, M. W.; Sathyamurthy, S.; Fleshler, S.; Sheng, H. P.; Miller, D. J.; Eley, S.; Civale, L.; Kayani, A.; Niraula, P. M.

    2015-11-09

    We demonstrate that 3.5-MeV oxygen irradiation can markedly enhance the in-field critical current of commercial second generation superconducting tapes with an exposure time of just 1 s per 0.8 cm{sup 2}. The speed demonstrated here is now at the level required for an industrial reel-to-reel post-processing. The irradiation is made on production line samples through the protective silver coating and does not require any modification of the growth process. From TEM imaging, we identify small clusters as the main source of increased vortex pinning.

  8. Protective riser-conductor for offshore structures

    SciTech Connect

    Rutherford, D. A.; Albers, G. P.

    1985-07-09

    A protective sleeve for fitting about the periphery of the leg of an offshore structure. The sleeve comprises means for carrying and enclosing a plurality of conductors. It further includes one or more inner rings; an outer jacket is fixedly spaced from the rings to define longitudinal passages within which the respective conductors are fixedly positioned. The sleeve is capable of deflecting packed ice and floating objects which represent possible sources of damage to the structure or to conductors.

  9. Development of a REBa2Cu3O7-δ multi-core superconductor with ‘inner split’ technology

    NASA Astrophysics Data System (ADS)

    Jin, Xinzhe; Oguro, Hidetoshi; Oshima, Yugo; Matsuda, Tetsuro; Maeda, Hideaki

    2016-04-01

    Recently, advanced research into fine filament technology for tape-shaped superconducting-coated conductors composed of REBa2Cu3O7-δ (RE123, RE: rare earth such as Gd or Y, 0 < δ < 1) has been carried out to improve performance in high magnetic fields by reducing the large diamagnetism of the RE123 superconducting layer. The major challenge for high-field NMR/MRI applications is to obtain high tensile stress tolerance above 500 MPa with a high critical current. In this study, a RE123 multi-core superconductor was fabricated via an ‘inner split’ method using a commercially available RE123 single-core coated conductor, where only the ceramics (RE123 and buffer layers) in wire are electrically separated to multi-filaments without superconducting current flow between the filaments. Experimental results show that wires having 2, 3, 4, or 5 cores have a high critical current (above 95% of the original) and maintain tensile stress tolerance above 650 MPa. The diamagnetism of the five-core wire is reduced ˜85% of the original at 7 T. Thus, the wire was optimized via inner split method for high-field use.

  10. Solid-state proton conductors

    SciTech Connect

    Jewulski, J.R.; Osif, T.L.; Remick, R.J.

    1990-12-01

    The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling and optimization studies. Correlation and optimization studies, to include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells including the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms. 164 refs., 27 figs., 13 tabs.

  11. Doped LZO buffer layers for laminated conductors

    DOEpatents

    Paranthaman, Mariappan Parans [Knoxville, TN; Schoop, Urs [Westborough, MA; Goyal, Amit [Knoxville, TN; Thieme, Cornelis Leo Hans [Westborough, MA; Verebelyi, Darren T [Oxford, MA; Rupich, Martin W [Framingham, MA

    2010-03-23

    A laminated conductor includes a metallic substrate having a surface, a biaxially textured buffer layer supported by the surface of the substrate, the biaxially textured buffer layer comprising LZO and a dopant for mitigating metal diffusion through the LZO, and a biaxially textured conductor layer supported by the biaxially textured buffer layer.

  12. Superconducting-magnetic heterostructures: a method of decreasing AC losses and improving critical current density in multifilamentary conductors.

    PubMed

    Glowacki, B A; Majoros, M

    2009-06-24

    Magnetic materials can help to improve the performance of practical superconductors on the macroscale/microscale as magnetic diverters and also on the nanoscale as effective pinning centres. It has been established by numerical modelling that magnetic shielding of the filaments reduces AC losses in self-field conditions due to decoupling of the filaments and, at the same time, it increases the critical current of the composite. This effect is especially beneficial for coated conductors, in which the anisotropic properties of the superconductor are amplified by the conductor architecture. However, ferromagnetic coatings are often chemically incompatible with YBa(2)Cu(3)O(7) and (Pb,Bi)(2)Sr(2)Ca(2)Cu(3)O(9) conductors, and buffer layers have to be used. In contrast, in MgB(2) conductors an iron matrix may remain in direct contact with the superconducting core. The application of superconducting-magnetic heterostructures requires consideration of the thermal and electromagnetic stability of the superconducting materials used. On one hand, magnetic materials reduce the critical current gradient across the individual filaments but, on the other hand, they often reduce the thermal conductivity between the superconducting core and the cryogen, which may cause destruction of the conductor in the event of thermal instability. A possible nanoscale method of improving the critical current density of superconducting conductors is the introduction of sub-micron magnetic pinning centres. However, the volumetric density and chemical compatibility of magnetic inclusions has to be controlled to avoid suppression of the superconducting properties. PMID:21828430

  13. Molten carbonate fuel cell cathode with mixed oxide coating

    DOEpatents

    Hilmi, Abdelkader; Yuh, Chao-Yi

    2013-05-07

    A molten carbonate fuel cell cathode having a cathode body and a coating of a mixed oxygen ion conductor materials. The mixed oxygen ion conductor materials are formed from ceria or doped ceria, such as gadolinium doped ceria or yttrium doped ceria. The coating is deposited on the cathode body using a sol-gel process, which utilizes as precursors organometallic compounds, organic and inorganic salts, hydroxides or alkoxides and which uses as the solvent water, organic solvent or a mixture of same.

  14. Comparison of hyperbolic and hyperboloid conductor electrostatics

    NASA Astrophysics Data System (ADS)

    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).

  15. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must...

  16. An Exploratory Comparison of Novice, Intermediate, and Expert Orchestral Conductors

    ERIC Educational Resources Information Center

    Bergee, Martin J.

    2005-01-01

    This study compared novice, "intermediate" (graduate student), and expert orchestral conductors. Two novice conductors, one graduate student in orchestral conducting, and one expert conductor led a university symphony orchestra in part of the first movement of Brahms's Symphony No. 2. Wired for sound, conductors attempted to verbalize their…

  17. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must...

  18. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must...

  19. The manufacture of flat conductor cable

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1974-01-01

    The major techniques are described for fabricating flat conductor cable (FCC). Various types of FCC, including unshielded, shielded, power, and signal, in both existing and conceptual constructions, are covered.

  20. Power conductor rail expansion joint

    SciTech Connect

    Plichta, D.G.

    1993-07-06

    A power conductor rail system is described, comprising: a first rail section linearly aligned with a second rail section, the first and second rail sections each having a rail web, the rail web having an upper flange, a lower flange, an intermediate portion connecting the upper flange and the lower flange, and metal cladding on the intermediate portion between the upper flange and the lower flange; a first half rail web extending longitudinally from the first rail section, the first half rail web including an elongated first slot extending in a longitudinal direction of the rail section; a second half rail web extending from the second rail section, the second half rail including an elongated second slot extending in longitudinal direction of the rail section; a slide plate; and a means for securing the first and second half rail webs longitudinally slidably together wherein a portion of the first half rail web and the second half rail web overlap and sandwich the slide plate therebetween.

  1. Muon dynamics in superprotonic conductors

    NASA Astrophysics Data System (ADS)

    Ikedo, Yutaka; Sugiyama, Jun; Nozaki, Hiroshi; Nishiyama, Kusuo; Matsuo, Yasumitsu; Lord, James S.

    2009-04-01

    In order to clarify the mechanism of high proton conductivity ( σ) for superprotonic conductors, MHXO4, where M=Cs and Rb, X=S and Se, μ+SR experiments have been performed in the temperature range between 250 and 450 K using single crystal samples. Here, MHXO4 exhibits extraordinary high σ at T above its structural phase transition ( Tc=414 K for CsHSO4) from a low- T monoclinic phase (Phase II) to a high- T tetragonal phase (Phase I). Since the asymmetry of weak transverse field (wTF) spectrum does not reach its maximum at ambient T, muonium (Mu) state is found to exist in both CsHSO4 and CsHSeO4. The Mu fraction in wTF spectrum for CsHSO4 is still a finite value even in Phase I, while the Mu state disappears in Phase I of CsHSeO4. The longitudinal field μ+SR measurements for observing the Mu state and its dynamics in CsHSO4, show fast Mu diffusion and the conversion from Mu to diamagnetic μ+ in whole T range measured. Considering the fact that the σ in Phase I of CsHSO4 is about 10 times larger than that of CsHSeO4, the Mu formation in Phase I implies the presence of the atomic hydrogen state and play a possible crucial role for the high σ in Phase I of CsHSO4.

  2. A Psychophysiological Case Study of Orchestra Conductors.

    PubMed

    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

  3. Influence of the air Layer Between the Conductor and the Layer Ofinsulating Material in Cable Products

    NASA Astrophysics Data System (ADS)

    Ivanova, Evgenia V.; Yashutina, Olga S.; Shidlovskiy, Stanisla V.

    2016-02-01

    There are developed mathematical model of physical and chemical processes of polymerization adhesive coating stranded cable. There are shown difference in the temperature distribution along the radius of the finished product in the presence of an air gap between the conductor and the rubber sheath. Also, due to the need to change process parameters with possible loose contacts inside the cable. Such as the temperature of the heating surface, feeding speed and dwell time in the oven.

  4. Broadband dielectric spectroscopy of inhomogeneous and composite weak conductors

    NASA Astrophysics Data System (ADS)

    Petzelt, J.; Nuzhnyy, D.

    2016-08-01

    In this paper, we discuss broadband dielectric spectroscopy from mHz up to the infrared range mainly for materials with inhomogeneous weak conductivity, including conductor-dielectric nanocomposites. Our discussion is based on the effective medium approximation (EMA) and experiments modeled by this approach are reviewed. We discuss core-shell composites modeled by coated-spheres (Hashin-Shtrikman model) and normal composites with a possible percolation of the conductor component resulting in sharp or smeared percolation threshold of the DC conductivity and diverging static permittivity in the former case. The sharp percolation threshold is modeled by the Bruggeman EMA or by general EMA with arbitrary percolation threshold and arbitrary critical exponents of the DC conductivity and static permittivity. For the case of smeared percolation threshold in the case of complex topologies, we use the Lichtenecker model allowing for partial percolation of both the components. Finally, numerous papers reporting negative permittivity in weakly conducting materials are criticized and concluded to be due to spurious effects.

  5. CHEMICAL SOLUTION DEPOSITION BASED OXIDE BUFFERS AND YBCO COATED CONDUCTORS

    SciTech Connect

    Paranthaman, Mariappan Parans

    2011-01-01

    We have reviewed briefly the growth of buffer and high temperature superconducting oxide thin films using a chemical solution deposition (CSD) method. In the Rolling-Assisted Biaxially Textured Substrates (RABiTS) process, developed at Oak Ridge National Laboratory, utilizes the thermo mechanical processing to obtain the flexible, biaxially oriented copper, nickel or nickel-alloy substrates. Buffers and Rare Earth Barium Copper Oxide (REBCO) superconductors have been deposited epitaxially on the textured nickel alloy substrates. The starting substrate serves as a template for the REBCO layer, which has substantially fewer weak links. Buffer layers play a major role in fabricating the second generation REBCO wire technology. The main purpose of the buffer layers is to provide a smooth, continuous and chemically inert surface for the growth of the REBCO film, while transferring the texture from the substrate to the superconductor layer. To achieve this, the buffer layers need to be epitaxial to the substrate, i.e. they have to nucleate and grow in the same bi-axial texture provided by the textured metal foil. The most commonly used RABiTS multi-layer architectures consist of a starting template of biaxially textured Ni-5 at.% W (Ni-W) substrate with a seed (first) layer of Yttrium Oxide (Y2O3), a barrier (second) layer of Yttria Stabilized Zirconia (YSZ), and a Cerium Oxide (CeO2) cap (third) layer. These three buffer layers are generally deposited using physical vapor deposition (PVD) techniques such as reactive sputtering. On top of the PVD template, REBCO film is then grown by a chemical solution deposition. This article reviews in detail about the list of oxide buffers and superconductor REBCO films grown epitaxially on single crystal and/or biaxially textured Ni-W substrates using a CSD method.

  6. Conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    DOEpatents

    Fischer, William H.; Yoon, Kue H.

    1984-04-10

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed perpendicular to the direction of travel of the inner conductor/insulating support assembly.

  7. Tunable Broadband Printed Carbon Transparent Conductor

    NASA Astrophysics Data System (ADS)

    Xu, Yue; Wan, Jiayu

    Transparent conductors have been widely applied in solar cells, transparent smart skins, and sensing/imaging antennas, etc. Carbon-based transparent conductor has attracted great attention for its low cost and broad range transparency. Ion intercalation has been known to highly dope graphitic materials, thereby tuning materials' optoelectronic properties. For the first time, we successfully tune the optical transmittance of a reduced graphene oxide (RGO)/CNT network from mid-IR range to visible range by means of Li-ion intercalation/deintercalation. We also observed a simultaneous increase of the electrical conductivity with the Li-ion intercalation. This printed carbon hybrid thin film was prepared through all solution processes and was easily scalable. This study demonstrates the possibility of using ion intercalation for low cost, tunable broadband transparent conductors.

  8. Thermal conductor for high-energy electrochemical cells

    DOEpatents

    Hoffman, Joseph A.; Domroese, Michael K.; Lindeman, David D.; Radewald, Vern E.; Rouillard, Roger; Trice, Jennifer L.

    2000-01-01

    A thermal conductor for use with an electrochemical energy storage device is disclosed. The thermal conductor is attached to one or both of the anode and cathode contacts of an electrochemical cell. A resilient portion of the conductor varies in height or position to maintain contact between the conductor and an adjacent wall structure of a containment vessel in response to relative movement between the conductor and the wall structure. The thermal conductor conducts current into and out of the electrochemical cell and conducts thermal energy between the electrochemical cell and thermally conductive and electrically resistive material disposed between the conductor and the wall structure. The thermal conductor may be fabricated to include a resilient portion having one of a substantially C-shaped, double C-shaped, Z-shaped, V-shaped, O-shaped, S-shaped, or finger-shaped cross-section. An elastomeric spring element may be configured so as to be captured by the resilient conductor for purposes of enhancing the functionality of the thermal conductor. The spring element may include a protrusion that provides electrical insulation between the spring conductor and a spring conductor of an adjacently disposed electrochemical cell in the presence of relative movement between the cells and the wall structure. The thermal conductor may also be fabricated from a sheet of electrically conductive material and affixed to the contacts of a number of electrochemical cells.

  9. Challenges and status of ITER conductor production

    NASA Astrophysics Data System (ADS)

    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

  10. Quench propagation velocity for highly stabilized conductors

    SciTech Connect

    Mints, R.G. |; Ogitsu, T. |; Devred, A.

    1995-05-01

    Quench propagation velocity in conductors having a large amount of stabilizer outside the multifilamentary area is considered. It is shown that the current redistribution process between the multifilamentary area and the stabilizer can strongly effect the quench propagation. A criterion is derived determining the conditions under which the current redistribution process becomes significant, and a model of effective stabilizer area is suggested to describe its influence on the quench propagation velocity. As an illustration, the model is applied to calculate the adiabatic quench propagation velocity for a conductor geometry with a multifilamentary area embedded inside the stabilizer.

  11. Measuring the Magnetic Force on a Current-Carrying Conductor.

    ERIC Educational Resources Information Center

    Herreman, W.; Huysentruyt, R.

    1995-01-01

    Describes a fast and simple method for measuring the magnetic force acting on a current-carrying conductor using a digital balance. Discusses the influence of current intensity and wire length on the magnetic force on the conductor. (JRH)

  12. Stators with improved conductor assembly and method of making same

    DOEpatents

    Dang, Dang Dinh; Blissenbach, Rolf; Schauer, David; Wattleworth, John; Milani, Michael; Hatch, Erik

    2013-07-30

    A stator includes a stator core, a plurality of slots, and a conductor. The plurality of slots are formed within the stator core. The conductor is disposed continuously within at least two of the plurality of openings.

  13. Method and apparatus for preparing multiconductor cable with flat conductors

    NASA Technical Reports Server (NTRS)

    Marcell, G. V. (Inventor)

    1969-01-01

    A method and apparatus for preparing flat conductor cable having a plurality of ribbon-like conductors disposed upon and adhesively bonded to the surface of a substrate is described. The conductors are brought into contact with the substrate surface, and while maintained in axial tension on said substrate, the combination is seated on a yieldably compressible layer to permit the conductor to become embedded into the surface of the substrate film.

  14. A Fabrication Method for Highly Stretchable Conductors with Silver Nanowires.

    PubMed

    Chang, Chia-Wei; Chen, Shih-Pin; Liao, Ying-Chih

    2016-01-01

    Stretchable electronics are identified as a key technology for electronic applications in the next generation. One of the challenges in fabrication of stretchable electronic devices is the preparation of stretchable conductors with great mechanical stability. In this study, we developed a simple fabrication method to chemically solder the contact points between silver nanowire (AgNW) networks. AgNW nanomesh was first deposited on a glass slide via spray coating method. A reactive ink composed of silver nanoparticle (AgNPs) precursors was applied over the spray coated AgNW thin films. After heating for 40 min, AgNPs were preferentially generated over the nanowire junctions to solder the AgNW nanomesh, and reinforced the conducting network. The chemically modified AgNW thin film was then transferred to polyurethane (PU) substrates by casting method. The soldered AgNW thin films on PU exhibited no obvious change in electrical conductivity under stretching or rolling process with elongation strains up to 120%. PMID:26862843

  15. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  16. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  17. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  18. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  19. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  20. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient...

  1. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient...

  2. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient...

  3. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient...

  4. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient...

  5. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  6. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to...

  7. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to...

  8. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  9. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate...

  10. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate...

  11. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate...

  12. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate...

  13. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  14. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  15. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  16. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate...

  17. Full tape thickness feature conductors for EMI structures

    DOEpatents

    Peterson, Kenneth A.; Knudson, Richard T.; Smith, Frank R.; Barner, Gregory

    2014-06-10

    Generally annular full tape thickness conductors are formed in single or multiple tape layers, and then stacked to produce an annular solid conductive wall for enclosing an electromagnetic isolation cavity. The conductors may be formed using punch and fill operations, or by flowing conductor-containing material onto the tape edge surfaces that define the interior sidewalls of the cavity.

  18. Multi-megampere current interruption from explosive deformation of conductors

    SciTech Connect

    Goforth, J.H.; Williams, A.H.; Marsh, S.P.

    1985-01-01

    Two approaches for using explosives to interrupt current flowing in solid conductors are described. One concept uses explosives to extrude the switch conductor into thin regions that fuse due to current in the switch. A preliminary scaling law is presented. The second approach employs dielectric jets to sever current carrying conductors. A feasibility experiment and an improved design are described.

  19. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductors. 77.503-1 Section 77.503-1... Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to meet the minimum current carrying capacity provided for in the National Electric Code, 1968. All...

  20. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductors. 77.503-1 Section 77.503-1... Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to meet the minimum current carrying capacity provided for in the National Electric Code, 1968. All...

  1. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductors. 77.503-1 Section 77.503-1... Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to meet the minimum current carrying capacity provided for in the National Electric Code, 1968. All...

  2. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Electrical Systems Manufacturer Requirements § 183.425...) Temperature rating of conductor insulation 60 °C (140 °F) 75 °C (167 °F) 80 °C (176 °F) 90 °C (194 °F) 105...

  3. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical conductors. 57.12004 Section 57.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES...

  4. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  5. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  6. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  7. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  8. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  9. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical conductors. 57.12004 Section 57.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES...

  10. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical conductors. 57.12004 Section 57.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES...

  11. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical conductors. 57.12004 Section 57.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12004...

  12. The Seebeck coefficient of superionic conductors

    SciTech Connect

    Mahan, G. D.

    2015-01-28

    We present a theory of the anomalous Seebeck coefficient found in the superionic conductor Cu{sub 2}Se. It has a phase transition at T = 400 K where the cations disorder but the anions do not. This disorder gives a temperature-dependent width to the electronic states in the conduction band. This width provides the anomalous Seebeck contribution.

  13. Preparation and properties of transparent conductors

    SciTech Connect

    Gordon, R.G.

    1996-12-31

    Transparent, electrically conductive films have been prepared from several different metal oxides, including those of tin, indium and zinc. Deposition methods for these materials are reviewed, and their properties summarized and compared. A figure of merit for a transparent conductor may be defined as the ratio of the electrical conductivity to the optical absorption coefficient of the film. The figure of merit for fluorine-doped zinc oxide is shown to be larger than that of other transparent conductors, such as boron-doped zinc oxide, fluorine-doped tin oxide, and tin-doped indium oxide. Physical, chemical and thermal durability, deposition temperature, and cost are other factors which may also influence the choice of material for a particular application.

  14. Local noise in a diffusive conductor

    NASA Astrophysics Data System (ADS)

    Tikhonov, E. S.; Shovkun, D. V.; Ercolani, D.; Rossella, F.; Rocci, M.; Sorba, L.; Roddaro, S.; Khrapai, V. S.

    2016-07-01

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes.

  15. Spin Transport in Multiply Connected Fractal Conductors

    NASA Astrophysics Data System (ADS)

    Lee, Bo-Ray; Chang, Ching-Ray; Klik, Ivo

    2014-12-01

    We consider spin and charge transport in a Sierpinski planar carpet; the interest here is its unique geometry. We analyze the fractal conductor as a combination of multiply connected quantum wires, and we observe the evolution of the transmission envelope in different fractal generations. For a fractal conductor dominated by resonant modes the transmission is characterized by strong fluctuations and conduction gaps. We show that charge and spin transport have different responses both to the presence of defects and to applied bias. At a high bias, or in a high-order fractal generation, spin accumulation is separated from charge accumulation because the larger drift velocity needs a longer polarization length, and the sample may turn into an insulator by the action of the defects. Our results are calculated numerically using the Keldysh Green function within the tight-binding framework.

  16. Local noise in a diffusive conductor

    PubMed Central

    Tikhonov, E. S.; Shovkun, D. V.; Ercolani, D.; Rossella, F.; Rocci, M.; Sorba, L.; Roddaro, S.; Khrapai, V. S.

    2016-01-01

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes. PMID:27466216

  17. Local noise in a diffusive conductor.

    PubMed

    Tikhonov, E S; Shovkun, D V; Ercolani, D; Rossella, F; Rocci, M; Sorba, L; Roddaro, S; Khrapai, V S

    2016-07-28

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes.

  18. Current diffusion in rail-gun conductors

    SciTech Connect

    Kerrisk, J.F.

    1982-06-01

    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.

  19. Local noise in a diffusive conductor.

    PubMed

    Tikhonov, E S; Shovkun, D V; Ercolani, D; Rossella, F; Rocci, M; Sorba, L; Roddaro, S; Khrapai, V S

    2016-01-01

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes. PMID:27466216

  20. Ionic conductors for solid oxide fuel cells

    DOEpatents

    Krumpelt, Michael; Bloom, Ira D.; Pullockaran, Jose D.; Myles, Kevin M.

    1993-01-01

    An electrolyte that operates at temperatures ranging from 600.degree. C. to 800.degree. C. is provided. The electrolyte conducts charge ionically as well as electronically. The ionic conductors include molecular framework structures having planes or channels large enough to transport oxides or hydrated protons and having net-positive or net-negative charges. Representative molecular framework structures include substituted aluminum phosphates, orthosilicates, silicoaluminates, cordierites, apatites, sodalites, and hollandites.

  1. Ionic conductors for solid oxide fuel cells

    SciTech Connect

    Krumpelt, M.; Bloom, I.D.; Pullockaran, J.D.; Myles, K.M.

    1991-12-31

    An electrolyte that operates at temperatures ranging from 600{degree}C to 800{degree}C is discussed. The electrolyte conducts charge ionically as well as electronically. The ionic conductors include molecular framework structures having planes or channels large enough to transport oxides or hydrated protons and having net-positive or net-negative charges. Representative molecular framework structures include substituted aluminum phosphates, orthosilicates, silicoaluminates, cordierites, apatites, sodalites, and hollandites.

  2. TOPICAL REVIEW: Tetrathiapentalene-based organic conductors

    NASA Astrophysics Data System (ADS)

    Misaki, Yohji

    2009-04-01

    The synthesis, structure and properties of tetrathiapentalene-based (TTP) organic conductors are reviewed. Among various TTP-type donors, bis-fused tetrathiafulvalene, 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene (BDT-TTP) and its derivatives afford many metallic radical cation salts stable down to low temperatures, regardless of the size and shape of the counter anions. Most BDT-TTP conductors have a β-type donor arrangement with almost uniform stacks. Introduction of appropriate substituents results in molecular packing that differs from the β-type. A vinylogous TTP, 2-(1,3-dithiol-2-ylidene)-5-(2-ethanediylidene-1,3-dithiole)-1,3,4,6-tetrathiapentalene (DTEDT) has yielded an organic superconductor (DTEDT)3Au(CN)2 as well as metallic radical cation salts, regardless of the counter anions. (Thio)pyran analogs of TTP, namely (T)PDT-TTP and its derivatives produce molecular conductors with novel molecular arrangements. A TTP analog with reduced π-electron system 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene (BDA-TTP) has afforded several organic superconductors. Highly conducting molecular metals with unusual oxidation states (+1, +5/3 and neutral) have been developed on the basis of 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene (BDT-TTP) derivatives and analogous metal derivatives M(dt)2 (M = Ni, Au).

  3. Testing of the 3M Company Composite Conductor

    SciTech Connect

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

    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.

  4. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2)...

  5. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2)...

  6. Flat conductor cable connectors with individually sealed contacts

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1972-01-01

    Information is presented on flat conductor cable connectors, a series with individually sealed contacts. Data are concerned with connector historical development, design requirements, and testing and costs.

  7. Actuating dielectric elastomers in pure shear deformation by elastomeric conductors

    SciTech Connect

    Wang, Yin; Chen, Baohong; Zhou, Jinxiong; Bai, Yuanyuan; Wang, Hong

    2014-02-10

    Pure shear experiments are commonly used to characterize dielectric elastomer (DE) material properties and to evaluate DE actuator/generator performance. It is increasingly important for many applications to replace conventional carbon grease electrodes with stretchable elastomeric conductors. We formulate a theory for DE with elastomeric conductors, synthesize transparent hydrogel as ionic conductors, and measure actuation of DE in pure shear deformation. Maximum 67% actuation strain is demonstrated. The theory agrees well with our measurement and also correlates well with reported experiments on DE with electronic conductors.

  8. Flat conductor cable for electrical packaging

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1972-01-01

    Flat conductor cable (FCC) is relatively new, highly promising means for electrical packaging and system integration. FCC offers numerous desirable traits (weight, volume and cost savings, flexibility, high reliability, predictable and repeatable electrical characteristics) which make it extremely attractive as a packaging medium. FCC, today, finds wide application in everything from integration of lunar equipment to the packaging of electronics in nuclear submarines. Described are cable construction and means of termination, applicable specifications and standards, and total FCC systems. A list of additional sources of data is also included for more intensive study.

  9. NASA Test Conductor Monitoring DIME competition

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A NASA test conductor at the top of the 2.2-second Drop Tower monitors a student lecture at a lower level. This was part of the Microgravity Environment (DIME) competition held April 23-25, 2002, at NASA's Glenn Research Center. Competitors included two teams from Sycamore High School, Cincinnati, OH, and one each from Bay High School, Bay Village, OH, and COSI Academy, Columbus, OH. DIME is part of NASA's education and outreach activities. Details are on line at http://microgravity.grc.nasa.gov/DIME_2002.html.

  10. Miniaturized bendable 400 MHz artificial magnetic conductor

    NASA Astrophysics Data System (ADS)

    Presse, Anthony; Tarot, Anne-Claude

    2016-04-01

    A bendable artificial magnetic conductor (AMC) with a resonant frequency of 400 MHz is proposed. The dimensions of the unit cell are 50 × 50 mm2 or 0.07 × 0.07 λ0. The miniaturization is achieved with closely coupled patches printed on each side of a 0.127-mm-thick dielectric substrate. This last one is stacked on a flexible 3-mm-thick silicone over a ground plane. An AMC prototype is simulated and manufactured. Also, a printed inverted-F antenna is used to highlight the bandwidth of the AMC.

  11. Noise and entanglement in quantum conductors

    SciTech Connect

    Lesovik, G. B.; Lebedev, A. V.

    2009-05-14

    In this article we discuss our two recent proposals on producing and detecting of entangled states in quantum conductors. First we analyze a setup where two electrons are scattered on a quantum dot with Coulomb repulsion and became orbitally entangled. Second, for identical noninteracting particles we suggest an operating scheme for the deliberate generation of spin-entangled electron pairs in a normal-metal mesoscopic structure with a fork geometry. The spin-entangled pair is created through a post-selection in the two branches of the fork. We also make comments on different ways of producing and quantifying the degree of entanglement.

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

    NASA Astrophysics Data System (ADS)

    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

  13. Novel processing of HTS based conductors

    SciTech Connect

    Ginley, D. S.; Venturini, E. L.; Kwak, J. F.; Baughman, R. J.; Bourcier, R. J.; Mitchell, M. A.; Morosin, B.; Halloran, J. W.; Neal, M. J.; Capone, D. W.

    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.

  14. Conductor gestures influence evaluations of ensemble performance.

    PubMed

    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

  15. Testing of the 3M Company ACCR Conductor

    SciTech Connect

    Stovall, J.P.; RIzy, D.T.; Kisner, R.A.; Deve, H.E.

    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

  16. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and...

  17. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and...

  18. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and...

  19. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and...

  20. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and...

  1. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... value that will cause an excessive or dangerous temperature in the conductor or conductor insulation. A... NEC 2002 or IEC 60092-202 (both incorporated by reference; see 46 CFR 110.10-1), then the next larger... overcurrent protective device. (e) Thermal devices. No thermal cutout, thermal relay, or other device...

  2. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... value that will cause an excessive or dangerous temperature in the conductor or conductor insulation. A... NEC 2002 or IEC 92-202 (both incorporated by reference; see 46 CFR 110.10-1), then the next larger... overcurrent protective device. (e) Thermal devices. No thermal cutout, thermal relay, or other device...

  3. Interplay of Ehrenfest and dephasing times in ballistic conductors.

    PubMed

    Altland, Alexander; Brouwer, Piet W; Tian, Chushun

    2007-07-20

    Quantum interference corrections in ballistic conductors require a minimal time: the Ehrenfest time. In this Letter, we investigate the fate of the interference corrections to quantum transport in bulk ballistic conductors if the Ehrenfest time and the dephasing time are comparable.

  4. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Grounding conductors for systems. 111.05-31 Section 111.05-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-31 Grounding conductors for systems. (a)...

  5. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Grounding conductors for systems. 111.05-31 Section 111.05-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-31 Grounding conductors for systems. (a)...

  6. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Grounding conductors for systems. 111.05-31 Section 111.05-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-31 Grounding conductors for systems. (a)...

  7. The Identification of Conductor-Distinguished Functions of Conducting

    ERIC Educational Resources Information Center

    Gumm, Alan J.; Battersby, Sharyn L.; Simon, Kathryn L.; Shankles, Andrew E.

    2011-01-01

    The purpose of the present study was to identify whether conductors distinguish functions of conducting similarly to functions implied in previous research. A sample of 84 conductors with a full range of experience levels (M = 9.8) and of a full range of large ensemble types and ensemble age levels rated how much they pay attention to 82…

  8. Elastically stretchable thin film conductors on an elastomeric substrate

    NASA Astrophysics Data System (ADS)

    Jones Harris, Joyelle Elizabeth

    Imagine a large, flat screen television that can be rolled into a small cylinder after purchase in the store and then unrolled and mounted onto the wall of a home. The electronic devices within the television must be able to withstand large deformation and tensile strain. Consider a robot that is covered with an electronic skin that simulates human skin. The skin would enable the machine to lift an elderly person with care and sensitivity. The skin will endure repeated deformation with the highest tensile strains being experienced at the robot's joints. These applications and many others will benefit from stretchable electronic circuitry. While several different methods have been employed to create stretchable electronics, all methods use a common tool -- stretchable conductors. Therefore, the goal of this thesis work was to fabricate elastically stretchable conductors that can be used in stretchable electronics. We deposited Au thin films on an elastomeric substrate, and the resulting conductors remained electrically continuous when stretched by 30% and more. We developed photolithographic processes that can be used to pattern elastically stretchable conductors with a 10 mum resolution. We fabricated bi-level stretchable conductors that are separated by an elastomeric insulator and are electrically connected through via holes in the insulator. We applied our bi-level conductors to create a stretchable resistor-inductor-capacitor (RLC) circuit with a tunable resonant frequency. We also used stretchable conductors to measure action potentials in biological samples. This thesis describes the fabrication and application of our elastically stretchable conductors.

  9. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  10. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  11. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  12. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  13. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  14. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... value that will cause an excessive or dangerous temperature in the conductor or conductor insulation. A... NEC 2002 or IEC 92-202 (both incorporated by reference; see 46 CFR 110.10-1), then the next larger... overcurrent protective device. (e) Thermal devices. No thermal cutout, thermal relay, or other device...

  15. Effect of the magnetic material on AC losses in HTS conductors in AC magnetic field carrying AC transport current

    NASA Astrophysics Data System (ADS)

    Wan, Xing-Xing; Huang, Chen-Guang; Yong, Hua-Dong; Zhou, You-He

    2015-11-01

    This paper presents an investigation on the AC losses in several typical superconducting composite conductors using the H-formulation model. A single superconducting strip with ferromagnetic substrate or cores and a stack of coated conductors with ferromagnetic substrates are studied. We consider all the coated conductors carrying AC transport currents and simultaneously exposed to perpendicular AC magnetic fields. The influences of the amplitude, frequency, phase difference and ferromagnetic materials on the AC losses are investigated. The results show that the magnetization losses of single strip and stacked strips have similar characteristics. The ferromagnetic substrate can increase the magnetization loss at low magnetic field, and decrease the loss at high magnetic field. The ferromagnetic substrate can obviously increase the transport loss in stacked strips. The trends of total AC losses of single strip and stacked strips are similar when they are carrying current or exposed to a perpendicular magnetic field. The effect of the frequency on the total AC losses of single strip is related to the amplitude of magnetic field. The AC losses decrease with increasing frequency in low magnetic field region while increase in high magnetic field region. As the phase difference changes, there is a periodic variation for the AC losses. Moreover, when the strip is under only the transport current and magnetic field, the ferromagnetic cores will increase the AC losses for large transport current or field.

  16. Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    DOEpatents

    Fischer, William H.

    1984-01-01

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly.

  17. Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    SciTech Connect

    Fischer, W.H.

    1984-04-24

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly. 7 figs.

  18. Alternative fiber optic conductor for laboratory practices

    NASA Astrophysics Data System (ADS)

    Calderon Ocampo, Juan F.; Jaramillo Florez, Samuel A.; Amaya Rodriguez, Juan C.

    1995-10-01

    Due to the high cost and difficulty in obtaining an optical fiber sample to be used in laboratory tests, we have given ourselves the task of looking for an adequate optical-fiber alternative for laboratory practices. We have as a result, found an object that can be used as an alternate optical conductor. This object called 'Venoclisis Hose', is a cylindrical plastic tube, hollow inside, whose main use has been in medical applications as a conveyor of liquids going in or coming out of the human body. In this document, the tests carried out and the results obtained to characterize the venoclisis as an optical fiber are described. This project was undertaken in order to propose the use of Venoclisis as an alternate optical fiber for laboratory work, due primarily to its low costs, as well as how easy it to acquire and measure its parameters as an optical fiber.

  19. Plasmonics with two-dimensional conductors

    PubMed Central

    Yoon, Hosang; Yeung, Kitty Y. M.; Kim, Philip; Ham, Donhee

    2014-01-01

    A wealth of effort in photonics has been dedicated to the study and engineering of surface plasmonic waves in the skin of three-dimensional bulk metals, owing largely to their trait of subwavelength confinement. Plasmonic waves in two-dimensional conductors, such as semiconductor heterojunction and graphene, contrast the surface plasmonic waves on bulk metals, as the former emerge at gigahertz to terahertz and infrared frequencies well below the photonics regime and can exhibit far stronger subwavelength confinement. This review elucidates the machinery behind the unique behaviours of the two-dimensional plasmonic waves and discusses how they can be engineered to create ultra-subwavelength plasmonic circuits and metamaterials for infrared and gigahertz to terahertz integrated electronics. PMID:24567472

  20. Conductor system for well bore data transmission

    SciTech Connect

    Galle, E.M.

    1990-04-03

    This patent describes an improved electrical transmission system for use in a fluid filled well bore. It comprises: a tubular member with threaded ends for connection in a drill string in a wellbore, having a transmitting end adapted for transmitting data signals, and a receiving end adapted for receiving data signals; a partition releasably carried by the transmitting end of the tubular member for mating with the tubular member; a compartment bounded in part by the partition and in part by the tubular member; a transmitter disposed in the compartment of the tubular member; seal means for sealing the compartment where the partition mates with the tubular member to protect the transmitter from the fluid in the well bore; and a flexible planar conductor.

  1. Plasmonics with two-dimensional conductors.

    PubMed

    Yoon, Hosang; Yeung, Kitty Y M; Kim, Philip; Ham, Donhee

    2014-03-28

    A wealth of effort in photonics has been dedicated to the study and engineering of surface plasmonic waves in the skin of three-dimensional bulk metals, owing largely to their trait of subwavelength confinement. Plasmonic waves in two-dimensional conductors, such as semiconductor heterojunction and graphene, contrast the surface plasmonic waves on bulk metals, as the former emerge at gigahertz to terahertz and infrared frequencies well below the photonics regime and can exhibit far stronger subwavelength confinement. This review elucidates the machinery behind the unique behaviours of the two-dimensional plasmonic waves and discusses how they can be engineered to create ultra-subwavelength plasmonic circuits and metamaterials for infrared and gigahertz to terahertz integrated electronics.

  2. Plasma bullets behavior in a tube covered by a conductor

    SciTech Connect

    Xian, Y. B.; Xu, H. T.; Lu, X. P. Pei, X. K.; Gong, W. W.; Lu, Y.; Liu, D. W.; Yang, Y.

    2015-06-15

    In this work, for better applications of atmospheric pressure plasma jets, the physics of plasma streamers in a glass tube with a part of it covered by a conductor is investigated. To better understand the propagation mechanism of plasma bullets in capillary tubes passing through a curved or narrow passage for some biomedical or material applications, the propagation of plasma streamers in a tube covered by a floating conductor is investigated. For a plasma streamer propagating in a tube covered by a conductor, the plasma streamer is suppressed and becomes shorter, and a secondary streamer is generated in the tube at the downstream end of the conductor. The larger the area covered by the conductor, or the thinner the tube, the stronger the plasma streamer is inhibited. The electric potential of the conductor is measured to be as high as 6 kV. On the other hand, a higher voltage applied on the HV electrode, or a higher gas flow rate will make the secondary plasma streamer longer. It is found that the capacitor formed by the conductor outside the tube and the wall of the tube plays an important role in inhibiting the original plasma streamer and generating the secondary streamer. Moreover, the active species generated by the original plasma play important role in generating a secondary plasma streamer.

  3. Mechanical behavior of a composite reinforced overhead conductor

    NASA Astrophysics Data System (ADS)

    Alawar, Ahmad

    A new type of overhead conductor with a polymer composite core is evaluated in terms of the mechanical properties and operating characteristics. The conductor is composed of trapezoidal O'-tempered aluminum wires helically wound around a hybrid glass/carbon composite core produced by pultrusion. The conductor is intended for electrical power transmission, and is designated ACCC/TW, for aluminum conductor composite core/trapezoidal wire. Measurements of core properties and conductor sag at high temperatures were compared to conventional ACSR (aluminum conductor, steel-reinforced) of the same diameter. The mechanical properties of ACCC/TW, such as the tensile strength, CTE and SAG performance, showed superiority to conventional ACSR. The ACCC/TW conductor also exhibited greater ampacity than ACSR conductor at all operating temperatures. A modification to a Numerical Sag Method for predicting conductor sag is presented that accurately predicts the observed bilinear sag behavior of composite conductors. The modified method is called the Hybrid Sag Method (HSM). It is used to predict the sag of conductors with conventional designs. The HSM predictions are compared with those obtained using a conventional graphical sag method. The HSM shows virtually the same accuracy as the graphical method for predicting sag for composite conductors operated under specific conditions. The HSM predictions of sag are validated by comparisons with experimental measurements. Tensile strength and storage modulus were measured to determine the temperature dependence of the composite core from 20°-200°C. The storage modulus was measured by dynamic mechanical analysis (DMA) and showed temperature dependence nearly identical to the tensile strength for both composites. The correlation between storage modulus and tensile strength was analyzed in terms of the temperature-dependent matrix shear strength, and the storage modulus behavior is presented as a basis for projecting the strength

  4. Insulation failure and externalized conductor of a single-coil Kentrox lead: an ongoing story?

    PubMed

    Bogossian, Harilaos; Mijic, Dejan; Frommeyer, Gerrit; Winter, Joachim

    2015-02-01

    Conductor externalization is a frequent complication with the St. Jude Medical Riata lead. Single case reports also reported externalization of conductors for dual-coil Biotronik leads. Up to now, conductor externalization has not yet been reported for any single coil leads. We report for the first time an externalization of conductors in a Biotronik Kentrox single-coil implantable cardioverter defibrillator (ICD) lead.

  5. 46 CFR 120.372 - Equipment and conductor grounding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... secondary windings of instrument transformers must be grounded. (b) On a nonmetallic vessel, where a...

  6. A microstructure continuum approach to electromagneto-elastic conductors

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

    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.

  8. A microstructure continuum approach to electromagneto-elastic conductors

    NASA Astrophysics Data System (ADS)

    Romeo, Maurizio

    2016-11-01

    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.

  9. On some characteristic properties of ATR liquid light conductors

    NASA Astrophysics Data System (ADS)

    Saydov, G. V.; Aleinik, A. I.

    2003-07-01

    Electronic spectra of aqueous solutions of the malachite green dye have been measured by liquid and solid spectroscopy. Particular characteristics of the light conductor itself have been shown to have no considerable effect on the results of the experiment.

  10. Electric and Magnetic Forces between Parallel-Wire Conductors.

    ERIC Educational Resources Information Center

    Morton, N.

    1979-01-01

    Discusses electric and magnetic forces between parallel-wire conductors and derives, in a simple fashion, order of magnitude estimates of the ratio of the likely electrostatic and electromagnetic forces for a simple parallel-wire balance. (Author/HM)

  11. 46 CFR 120.372 - Equipment and conductor grounding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... secondary windings of instrument transformers must be grounded. (b) On a nonmetallic vessel, where a...

  12. New resistivity for high-mobility quantum Hall conductors

    NASA Technical Reports Server (NTRS)

    Mceuen, P. L.; Szafer, A.; Richter, C. A.; Alphenaar, B. W.; Jain, J. K.

    1990-01-01

    Measurements showing dramatic nonlocal behavior in the four-terminal resistances of a high-mobility quantum Hall conductor are presented. These measurements illustrate that the standard definition of the resistivity tensor is inappropriate, but they are in excellent agreement with a new model of the conductor that treats the edge and bulk conducting pathways independently. This model uses a single intensive parameter, analogous to a local resistivity for the bulk channel only, to characterize the system.

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

    NASA Technical Reports Server (NTRS)

    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.

  14. Aluminide coatings

    SciTech Connect

    Henager, Jr; Charles, H; Shin, Yongsoon; Samuels, William D

    2009-08-18

    Disclosed herein are aluminide coatings. In one embodiment coatings are used as a barrier coating to protect a metal substrate, such as a steel or a superalloy, from various chemical environments, including oxidizing, reducing and/or sulfidizing conditions. In addition, the disclosed coatings can be used, for example, to prevent the substantial diffusion of various elements, such as chromium, at elevated service temperatures. Related methods for preparing protective coatings on metal substrates are also described.

  15. COATED ALLOYS

    DOEpatents

    Harman, C.G.; O'Bannon, L.S.

    1958-07-15

    A coating is described for iron group metals and alloys, that is particularly suitable for use with nickel containing alloys. The coating is glassy in nature and consists of a mixture containing an alkali metal oxide, strontium oxide, and silicon oxide. When the glass coated nickel base metal is"fired'' at less than the melting point of the coating, it appears the nlckel diffuses into the vitreous coating, thus providing a closely adherent and protective cladding.

  16. Local electron heating in nanoscopic conductors

    NASA Astrophysics Data System (ADS)

    D'Agosta, Roberto; Sai, Na; di Ventra, Massimiliano

    2007-03-01

    The electron current density in nanoscale junctions is typically several orders of magnitude larger than the corresponding one in bulk electrodes. Consequently, the electron-electron scattering rate increases substantially in the junction. This leads to local electron heating of the underlying Fermi sea [1] in analogy to the local ionic heating that is due to the increased electron-phonon scattering rates [2]. By using a novel hydrodynamic formulation of transport [3], we predict the bias dependence of local electron heating in quasi-ballistic nanoscale conductors [1], its effect on ionic heating [1], and the consequent observable changes in the inelastic conductance [4]. [1] R. D'Agosta, N. Sai and M. Di Ventra, accepted in Nano Letters (2006). [2] Y.-C. Chen, M. Zwolak, and M. Di Ventra, Nano Lett. 3, 1961 (2003); Nano Lett. 4, 1709 (2004); Nano Lett. 5, 621 (2005). M. J. Montgomery, T. N. Todorov, and A. P. Sutton, J. Phys. Cond. Matt. 14, 5377 (2002). [3] R. D'Agosta and M. Di Ventra, J. Phys. Cond. Matt. in press. [4] R. D'Agosta and M. Di Ventra, in preparation.

  17. The liver: conductor of systemic iron balance

    PubMed Central

    Meynard, Delphine; Babitt, Jodie L.

    2014-01-01

    Iron is a micronutrient essential for almost all organisms: bacteria, plants, and animals. It is a metal that exists in multiple redox states, including the divalent ferrous (Fe2+) and the trivalent ferric (Fe3+) species. The multiple oxidation states of iron make it excellent for electron transfer, allowing iron to be selected during evolution as a cofactor for many proteins involved in central cellular processes including oxygen transport, mitochondrial respiration, and DNA synthesis. However, the redox cycling of ferrous and ferric iron in the presence of H2O2, which is physiologically present in the cells, also leads to the production of free radicals (Fenton reaction) that can attack and damage lipids, proteins, DNA, and other cellular components. To meet the physiological needs of the body, but to prevent cellular damage by iron, the amount of iron in the body must be tightly regulated. Here we review how the liver is the central conductor of systemic iron balance and show that this central role is related to the secretion of a peptide hormone hepcidin by hepatocytes. We then review how the liver receives and integrates the many signals that report the body’s iron needs to orchestrate hepcidin production and maintain systemic iron homeostasis. PMID:24200681

  18. Conductor gestures influence evaluations of ensemble performance

    PubMed Central

    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

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

    PubMed

    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

  20. Safety analysis of the GEM Detector Magnet conductor

    SciTech Connect

    Ferri, M.A.; Hassenzahl, W.V.

    1993-08-27

    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 {approximately} 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 {times} 10{sup 7} mho/m, is at least 100 times greater than the minimum value necessary to limit the hotspot temperature to {approximately} 50 K after two seconds. This report describes the results of calculations based on a realistic assumption of GEM conductor performance during a quench.

  1. Computer simulations of isolated conductors in electrostatic equilibrium.

    PubMed

    Chang, Herng-Hua

    2008-11-01

    A computer simulation model is introduced to study the characteristics of isolated conductors in electrostatic equilibrium. Drawing an analogy between electrons and how they move to the surface of isolated conductors, we randomly initialize a large number of particles inside a small region at the center of simulated conductors and advance them according to their forces of repulsion. By use of optimized numerical techniques of the finite-size particle method associated with Poisson's equation, the particles are quickly advanced using a fast Fourier transform and their charge is efficiently shared using the clouds-in-cells method. The particle populations in the simulations range from 50x10;{3} to 1x10;{6} that move in various computation domains equal to 128x128 , 256x256 , and 512x512 grids. When the particles come to an electrostatic equilibrium, they lie on the boundaries of the simulated conductors, from which the equilibrium properties are obtained. Consistent with the theory of electrostatics and charged conductors, we found that the particles move in response to the conductor geometry in such a way that the electrostatic energy is minimized. Good approximation results for the equilibrium properties were obtained using the proposed computer simulation model.

  2. The fate of sounds in conductors' brains: an ERP study.

    PubMed

    Nager, Wido; Kohlmetz, Christine; Altenmüller, Eckart; Rodriguez-Fornells, Antoni; Münte, Thomas F

    2003-06-01

    Professional music conductors are required to home in on a particular musician but at the same time have to monitor the entire orchestra. It was hypothesized that this unique experience should be reflected by superior auditory spatial processing. Event-related brain potentials were obtained, while conductors, professional pianists, and non-musicians listened to sequences of bandpass-filtered noise-bursts presented in random order from six speakers, three located in front and three to the right of the subjects. In different runs, subjects either attended the centermost or the most peripheral speaker in order to detect slightly deviant noise-bursts. For centrally located speakers, the ERPs showed a typical Nd attention effect for the relevant location with a steep decline for the neighboring speakers in all subject groups. For peripheral speakers, only the conductors showed attentional selectivity, while the Nd effect was of similar size for all three peripheral speakers in the other two groups. These ERP effects were paralleled by an enhanced behavioral selectivity in peripheral auditory space in conductors. Moreover, the pre-attentive monitoring of the entire auditory scene indexed by the mismatch negativity was superior in musicians compared to non-musicians. In conductors, the MMN was followed by a positivity suggesting an attention shift towards the deviant stimuli in this group only.

  3. Use of ion conductors in the pyrochemical reduction of oxides

    DOEpatents

    Miller, W.E.; Tomczuk, Z.

    1994-02-01

    An electrochemical process and electrochemical cell for reducing a metal oxide are provided. First the oxide is separated as oxygen gas using, for example, a ZrO[sub 2] oxygen ion conductor anode and the metal ions from the reduction salt are reduced and deposited on an ion conductor cathode, for example, sodium ion reduced on a [beta]-alumina sodium ion conductor cathode. The generation of and separation of oxygen gas avoids the problem with chemical back reaction of oxygen with active metals in the cell. The method also is characterized by a sequence of two steps where an inert cathode electrode is inserted into the electrochemical cell in the second step and the metallic component in the ion conductor is then used as the anode to cause electrochemical reduction of the metal ions formed in the first step from the metal oxide where oxygen gas formed at the anode. The use of ion conductors serves to isolate the active components from chemically reacting with certain chemicals in the cell. While applicable to a variety of metal oxides, the invention has special importance for reducing CaO to Ca[sup o] used for reducing UO[sub 2] and PuO[sub 2] to U and Pu. 2 figures.

  4. Use of ion conductors in the pyrochemical reduction of oxides

    DOEpatents

    Miller, William E.; Tomczuk, Zygmunt

    1994-01-01

    An electrochemical process and electrochemical cell for reducing a metal oxide are provided. First the oxide is separated as oxygen gas using, for example, a ZrO.sub.2 oxygen ion conductor anode and the metal ions from the reduction salt are reduced and deposited on an ion conductor cathode, for example, sodium ion reduced on a .beta.-alumina sodium ion conductor cathode. The generation of and separation of oxygen gas avoids the problem with chemical back reaction of oxygen with active metals in the cell. The method also is characterized by a sequence of two steps where an inert cathode electrode is inserted into the electrochemical cell in the second step and the metallic component in the ion conductor is then used as the anode to cause electrochemical reduction of the metal ions formed in the first step from the metal oxide where oxygen gas formed at the anode. The use of ion conductors serves to isolate the active components from chemically reacting with certain chemicals in the cell. While applicable to a variety of metal oxides, the invention has special importance for reducing CaO to Ca.degree. used for reducing UO.sub.2 and PuO.sub.2 to U and Pu.

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

    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.

  6. Current distribution and inductance calculations for rail-gun conductors

    SciTech Connect

    Kerrisk, J.F.

    1981-11-01

    A method has been developed to calculate the current-density distribution, magnetic field, and inductance of rail-gun or flux-compression generator rails, or other long, parallel conductors of arbitrary cross section, in the high-frequency limit. The results represent initial estimates of these quantities in rail-gun circuits before current or magnetic-field diffusion has significantly changed the current distribution. The numerical procedure determines the current-density distribution using an existing technique originally developed for calculation of charge distribution on equipotential surfaces. The inductance and magnetic field are calculated from the current distribution. Calculations were performed for four systems: two cylindrical conductors, two rectangular conductors, two rectangular conductors in a tube, and flux-compression generators used at Los Alamos National Laboratory. Inductances of two rectangular conductors and of flux-compression generators were fitted to empirical equations to simplify their further use. Calculated current distributions and inductances were compared with other theoretical calculations and with measured data. The comparisons indicate that results from this method accurately predict the current-density distribution and inductance of these systems in the high-frequency limit.

  7. Hearing status among Norwegian train drivers and train conductors

    PubMed Central

    2013-01-01

    Background There is a general perception that train drivers and conductors may be at increased risk of developing noise-induced hearing loss. Aims To study job-related hearing loss among train drivers and train conductors. Methods Audiograms from train drivers and train conductors were obtained from the medical records of the occupational health service of the major Norwegian railway company. The results were compared with audiograms from an internal control group of railway workers and an external reference group of people not occupationally exposed to noise. The monaural hearing threshold level at 4kHz, the mean binaural value at 3, 4 and 6kHz and the prevalence of audiometric notches (≥25 dB at 4kHz) were used for comparison. Results Audiograms were available for 1567 drivers, 1565 conductors, 4029 railway worker controls and 15 012 people not occupationally exposed to noise. No difference in hearing level or prevalence of audiometric notches was found between study groups after adjusting for age and gender. Conclusions Norwegian train drivers and conductors have normal hearing threshold levels comparable with those in non-exposed groups. PMID:24204021

  8. Search for solid conductors of Na(+) and K(+) ions: Five new conductors

    NASA Technical Reports Server (NTRS)

    Singer, J.; Kautz, H.; Fielder, W. L.; Fordyce, J.

    1975-01-01

    Five conductors of three structure types were discovered which, as solids, can transport Na(+) or K(+) ions with conductivities of approximately .00001/(omega cm) at 300 K. These compounds are: (1) the pyrochlores NaTaWO6 and NaTa2O5F, both with an activation energy for conduction delta E of 21 kJ/mole; (2) the bodycentered cubic form of NaSbO3, with delta E = 42 kJ/mole; and (3) the niobates 2Na2O with 3Nb2O5 and 2K2O with 3Nb2O5, with the alkali ions probably in open layers of the incompletely determined structure; delta E = 17 kJ/mole. On the basis of approximately 40 structure types, some generalizations were made regarding the relation between structure and ionic transport.

  9. Tension layer winding of cable-in-conduit conductor

    SciTech Connect

    Devernoe, A.; Ciancetta, G.; King, M.; Parizh, M.; Painter, T.; Miller, J.

    1996-07-01

    A 710 mm i.d. by 440 mm long, 6 layer Cable-in-Conduit (CIC) coil was precision tension layer wound with Incoloy 908 jacketed conductor to model winding technology that will be used for the Nb{sub 3}Sn outsert coils of the 45 Tesla Hybrid Magnet Project at the US National High Magnetic Field Laboratory. This paper reports on the set up of a new winding facility with unique capabilities for insulating and winding long length CIC conductor and on special procedures which were developed to wind and support layer to layer transitions and to safely form conductor into and out of the winding. Analytical methods used to predict conduit keystoning, springback and back tensioning requirements before winding are reported in comparison to results obtained during winding and actual winding build-up dimensions on a layer by layer basis in comparison to design requirements.

  10. Mobility propagation and dynamic facilitation in superionic conductors

    SciTech Connect

    Annamareddy, Ajay Eapen, Jacob

    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.

  11. Quantum Optics Theory of Electronic Noise in Coherent Conductors

    NASA Astrophysics Data System (ADS)

    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)].

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

    PubMed

    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)].

  13. Transient finite element method using edge elements for moving conductor

    SciTech Connect

    Tani, Koji; Nishio, Takayuki; Yamada, Takashi ); Kawase, Yoshihiro . Dept. of Information Science)

    1999-05-01

    For the next generation of high speed railway systems and automobiles new braking systems are currently under development. These braking systems take into account the eddy currents, which are produced by the movement of the conductor in the magnetic field. For their optimum design, it is necessary to know the distribution of eddy currents in the moving conductor. The finite element method (FEM) is often used to simulate them. Here, transient finite element method using edge elements for moving conductor is presented. Here the magnetic vector potential is interpolated at the upwind position and the time derivative term is discretized by the backward difference method. As a result, the system matrix becomes symmetric and the ICCG method is applicable to solve the matrix. This method is used to solve an eddy current rail brake system. The results demonstrate that this approach is suitable to solve transient problems involving movement.

  14. Metal Coatings

    NASA Technical Reports Server (NTRS)

    1994-01-01

    During the Apollo Program, General Magnaplate Corporation developed process techniques for bonding dry lubricant coatings to space metals. The coatings were not susceptible to outgassing and offered enhanced surface hardness and superior resistance to corrosion and wear. This development was necessary because conventional lubrication processes were inadequate for lightweight materials used in Apollo components. General Magnaplate built on the original technology and became a leader in development of high performance metallurgical surface enhancement coatings - "synergistic" coatings, - which are used in applications from pizza making to laser manufacture. Each of the coatings is designed to protect a specific metal or group of metals to solve problems encountered under operating conditions.

  15. Conductor design for the VLHC transmission line magnet

    SciTech Connect

    Foster, G.W.; Kashikhin, V.; McAshan, M.; Mazur, P.O.; Piekarz, H.; Volk, J.T.; Walker, R.

    1999-03-01

    The transmission line magnet [1] is under development for the Very Large Hadron Collider (VLHC) at Fermilab with the expectation that it’s cost will be several times less (per Tesla-meter) than conventional superconducting magnets. It is a dual-aperture warm-iron superferric magnet built around an 80kA superconducting transmission line. The superconductor consists of 8 Rutherford (SSC Outer) cables in an Invar pipe jacket. The conductor design requirements and development program is described. A 100kA conductor test facility based on inductive coupling is described.

  16. Scaling theory of phase-coherent metallic conductors

    NASA Astrophysics Data System (ADS)

    Macêdo, A. M.

    2002-07-01

    We present a scaling theory for describing the smooth crossover from ballistic to diffusive transport in phase-coherent metallic conductors. The theory confirms a recent conjecture by Beenakker [Rev. Mod. Phys. 69, 731 (1997)], and represents a substantial improvement in the two-terminal version of Nazarov's circuit theory [Phys. Rev. Lett. 73, 134 (1994); 73, 1420 (1994)]. In addition, our approach allows for the explicit inclusion of interfaces of arbitrary transparency, which are described using the supersymmetric nonlinear σ model. The problem of two identical barriers separated by a diffusive conductor is solved exactly, and expressions for both the normal and Andreev conductances are presented.

  17. A base-metal conductor system for silicon solar cells

    NASA Technical Reports Server (NTRS)

    Coleman, M. G.; Pryor, R. A.; Sparks, T. G.

    1980-01-01

    Solder, copper, and silver are evaluated as conductor layer metals for silicon solar cell metallization on the basis of metal price stability and reliability under operating conditions. Due to its properties and cost, copper becomes an attractive candidate for the conductor layer. It is shown that nickel operates as an excellent diffusion barrier between copper and silicon while simultaneously serving as an electrical contact and mechanical contact to silicon. The nickel-copper system may be applied to the silicon by plating techniques utilizing a variety of plating bath compositions. Solar cells having excellent current-voltage characteristics are fabricated to demonstrate the nickel-copper metallization system.

  18. Embedded Fin-Like Metal/CNT Hybrid Structures for Flexible and Transparent Conductors.

    PubMed

    Jiang, Di; Wang, Nan; Edwards, Michael; Mu, Wei; Nylander, Andreas; Fu, Yifeng; Jeppson, Kjell; Liu, Johan

    2016-03-01

    In this paper, an embedded fin-like metal-coated carbon nanotube (Fin-M/CNT) structure is demonstrated for flexible and transparent conductor wire applications. Embedded in a polydimethylsiloxane polymeric substrate, Fin-M/CNT wires with a minimum width of 5 μm and a minimum pitch of 10 μm have been achieved. Direct current resistances of single Fin-M/CNT wires, where the supporting CNT structures have been covered by Ti/Al/Au metal coatings of different thicknesses, have been measured. The high aspect ratio of the fin-like structures not only improves the adhesion between the wires and the polymeric substrate, but also yields a low resistance at a small surface footprint. In addition, transparent Fin-M/CNT grid lines with hexagonal patterns, with a sheet resistance of as low as 45 Ω sq(-1) , have been achieved at an optical transmittance of 88%. The robustness of the Fin-M/CNT structures has been demonstrated in bending tests up to 500 cycles and no significant changes in wire resistances are observed. PMID:26766128

  19. Embedded Fin-Like Metal/CNT Hybrid Structures for Flexible and Transparent Conductors.

    PubMed

    Jiang, Di; Wang, Nan; Edwards, Michael; Mu, Wei; Nylander, Andreas; Fu, Yifeng; Jeppson, Kjell; Liu, Johan

    2016-03-01

    In this paper, an embedded fin-like metal-coated carbon nanotube (Fin-M/CNT) structure is demonstrated for flexible and transparent conductor wire applications. Embedded in a polydimethylsiloxane polymeric substrate, Fin-M/CNT wires with a minimum width of 5 μm and a minimum pitch of 10 μm have been achieved. Direct current resistances of single Fin-M/CNT wires, where the supporting CNT structures have been covered by Ti/Al/Au metal coatings of different thicknesses, have been measured. The high aspect ratio of the fin-like structures not only improves the adhesion between the wires and the polymeric substrate, but also yields a low resistance at a small surface footprint. In addition, transparent Fin-M/CNT grid lines with hexagonal patterns, with a sheet resistance of as low as 45 Ω sq(-1) , have been achieved at an optical transmittance of 88%. The robustness of the Fin-M/CNT structures has been demonstrated in bending tests up to 500 cycles and no significant changes in wire resistances are observed.

  20. 49 CFR Appendix B to Part 242 - Procedures for Submission and Approval of Conductor Certification Programs

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Conductor Certification Programs B Appendix B to Part 242 Transportation Other Regulations Relating to... Conductor Certification Programs This appendix establishes procedures for the submission and approval of a... Conductor Certification Program The final section of the request must contain a summary of how the...

  1. 49 CFR Appendix B to Part 242 - Procedures for Submission and Approval of Conductor Certification Programs

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Conductor Certification Programs B Appendix B to Part 242 Transportation Other Regulations Relating to... Conductor Certification Programs This appendix establishes procedures for the submission and approval of a... Conductor Certification Program The final section of the request must contain a summary of how the...

  2. 49 CFR Appendix B to Part 242 - Procedures for Submission and Approval of Conductor Certification Programs

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Conductor Certification Programs B Appendix B to Part 242 Transportation Other Regulations Relating to... Conductor Certification Programs This appendix establishes procedures for the submission and approval of a... Conductor Certification Program The final section of the request must contain a summary of how the...

  3. Development of flat conductor cable for commercial and residential wiring

    NASA Technical Reports Server (NTRS)

    Carden, J. R.

    1977-01-01

    The overall spectrum of the space technology spin-off development project: development of Flat Conductor Cable (FCC) for commercial and residential wiring, is presented. A discussion of the background, program milestones, industry participants, system outgrowth, hardware availability, cost estimates, and overall status of the program is presented for the 1970-to-present time period.

  4. 46 CFR 120.372 - Equipment and conductor grounding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Equipment and conductor grounding. 120.372 Section 120.372 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS ELECTRICAL INSTALLATION Power Sources and Distribution...

  5. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  6. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  7. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  8. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  9. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  10. Conductor and Ensemble Performance Expressivity and State Festival Ratings

    ERIC Educational Resources Information Center

    Price, Harry E.; Chang, E. Christina

    2005-01-01

    This study is the second in a series examining the relationship between conducting and ensemble performance. The purpose was to further examine the associations among conductor, ensemble performance expressivity, and festival ratings. Participants were asked to rate the expressivity of video-only conducting and parallel audio-only excerpts from a…

  11. Undergraduate Conductors' and Conducting Teachers' Perceptions of Basic Conducting Efficacy

    ERIC Educational Resources Information Center

    Silvey, Brian A.; Baumgartner, Christopher M.

    2016-01-01

    The purpose of this study was to examine undergraduate conductors' and conducting teachers' perceptions about basic conducting efficacy. At the beginning and end of the semester, undergraduate students (N = 19) enrolled in a basic conducting course (a) were surveyed about the importance of certain skills necessary for being an effective conductor…

  12. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2010 CFR

    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 SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1920...

  13. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1920...

  14. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1920...

  15. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1920...

  16. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Diagnostic Devices § 868.1920...

  17. Improved Writing-Conductor Designs For Magnetic Memory

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    Writing currents reduced to practical levels. Improved conceptual designs for writing conductors in micromagnet/Hall-effect random-access integrated-circuit memory reduces electrical current needed to magnetize micromagnet in each memory cell. Basic concept of micromagnet/Hall-effect random-access memory presented in "Magnetic Analog Random-Access Memory" (NPO-17999).

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

    ERIC Educational Resources Information Center

    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…

  19. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., Subpart 111.30. (c) Fuses and circuitbreakers. If the allowable current-carrying capacity of the conductor does not correspond to a standard rating for fuses or circuitbreakers that meets Section 240.6 of NFPA NEC 2002 or IEC 92-202 (both incorporated by reference; see 46 CFR 110.10-1), then the next...

  20. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Grounding conductors for systems. 111.05-31 Section 111... ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-31... grounding the neutral of an alternating-current system must meet Table 111.05-31(b). Table...

  1. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Grounding conductors for systems. 111.05-31 Section 111... ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-31... grounding the neutral of an alternating-current system must meet Table 111.05-31(b). Table...

  2. Universality of Shot Noise in Mesoscopic Diffusive Conductors.

    NASA Astrophysics Data System (ADS)

    Sukhorukov, Eugene; Loss, Daniel

    1998-03-01

    Shot noise is the time-dependent fluctuations in the electrical current caused by the discreteness of the electron charge. In mesoscopic conductors the shot noise is suppressed below the noise of a Poisson process due to correlations in the electron transmission imposed by the Pauli principle. In diffusive conductors with purely elastic scattering the suppression factor is 1/3, and in the case of strong electron-electron scattering it is √3/4 (C.W.J. Beenakker and M. Büttiker, Phys. Rev. B46, 1889 (1992); K.E. Nagaev, Phys. Lett. A169, 103 (1992); Phys. Rev. B52, 4740 (1995)). Subsequently, it has been proven by Nazarov that the 1/3 suppression is universal and holds for an arbitrary two-terminal geometry of the conductor and distribution of impurities. Using a different approach, we confirm the universality of the 1/3 and prove the universality of the √3/4 suppressions. A possible generalization of our results to the case of multiterminal conductors is discussed.

  3. Phenomenology of electromagnetic coupling: Conductors penetrating an aperture

    SciTech Connect

    Wright, D.B.; King, R.J.

    1987-06-01

    The purpose of this study was to investigate the coupling effects of penetrating conductors through free-standing apertures. This penetrating conductor and aperture arrangement are referred to as a modified aperture. A penetrating conductor is defined here to be a thin, single wire bent twice at 90 angles. The wire was inserted through a rectangular aperture in a metal wall. Vertical segments on both sides of the wall coupled energy from one region to the other. Energy was incident upon the modified aperture from what is referred to as the exterior region. The amount of coupling was measured by a D sensor on the other (interior) side of the wall. This configuration of an aperture in a metal wall was used as opposed to an aperture in a cavity in order to simplify the interpretation of resulting data. The added complexity of multiple cavity resonances was therefore eliminated. Determining the effects of penetrating conductors on aperture coupling is one of several topics being investigated as part of on-going research at Lawrence Livermore National Laboratory on the phenomenology of electromagnetic coupling. These phenomenology studies are concerned with the vulnerability of electronic systems to high intensity electromagnetic fields. The investigation is relevant to high altitude EMP (HEMP), enhanced HEMP (EHEMP), and high power microwave (HPM) coupling.

  4. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... of overcurrent protection for conductors is to open the electric circuit if the current reaches a... NEC 2002 or IEC 60092-202 (both incorporated by reference; see 46 CFR 110.10-1), then the next...

  5. Glass ceramic ionic conductor materials and method of making

    SciTech Connect

    Badzioch, S.

    1985-03-26

    Solid, crystalline glass ceramic compositions which are useful as ionic conductor materials, especially for use as solid electrolytes in high temperature, high energy density storage batteries. The glass ceramics are derived from sodium or calcium borates containing one or more metal halide, preferably the chlorides and bromides of the metals from Group 2 to 8 of the Periodic Table of the Elements.

  6. The Review on the Charge Distribution on the Conductor Surface

    ERIC Educational Resources Information Center

    Matehkolaee, M. Jafari; Asrami, A. Naderi

    2013-01-01

    In this paper we have a full review on the surface charge density at disordered conductor surfaces. Basically, reading text books does not resolve ambiguities in this field. As far as is possible, we have tried to the concepts easier to turn. In fact we will answer two questions. One of them is that why do charges tend to go where the curvature is…

  7. Diffusion of fast rising strong magnetic fields into conductors

    NASA Astrophysics Data System (ADS)

    Labetskaya, N. A.; Oreshkin, V. I.; Chaikovsky, S. A.; Datsko, I. M.; Kuskova, N. I.; Rud, A. D.

    2014-11-01

    The basic processes occurring in a conductor exploding in a current skinning mode are the propagation of a nonlinear magnetic diffusion wave in the conductor and the formation of low-temperature plasma at its surface. An experimental study of the phenomenon of nonlinear magnetic diffusion into conductors in magnetic fields of induction rising at a rate up to 3·109 T/s was carried out on the MIG generator capable of producing a peak current up to 2.5 MA within a rise time of 100 ns. It has been found experimentally that the average velocity of a nonlinear magnetic diffusion wave in an aluminum conductor placed in a strong magnetic field (up to 300 T) rising at a high rate (on average, 3·109 T/s) is (2.7÷3.3)·105 cm/s. This is comparable to the velocity of sound in aluminum under normal conditions and reasonably agrees with predictions of numerical simulations.

  8. Test results and analyses of conductor short samples for China first PF conductor

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Wu, Yu; Long, Feng; Li, Shaolei

    2011-02-01

    The first China PF conductor sample (CNPF1) which was made of one single cable section with hairpin configuration and without bottom joint was fabricated with Chinese NbTi strands and assembled at ENEA and CEA according to the requirements of the SULTAN test facility. The sample was equipped with temperature sensors and voltage taps at CEA according to the test program. The test program included DC performance, cyclic loading, AC loss, and MQE test. The sample exhibited a good performance which fit well with the requirement in the procurement arrangement (PA). But most of the current sharing temperature ( T cs) tests showed a suddenly voltage take-off or fast voltage transition with take-off electric field below the threshold of 10 μV/m. The temperature could be considered as quench temperature ( T q) but not exactly T cs. At 35 kA and background field of 3.5 T, the temperature T q was 6.94 K. Even after 2000 cycles at the condition of 6.5 T and 19 kA, the T q remained unchanged.

  9. Research on High Temperature Ceramic Insulation for Electrical Conductors

    NASA Technical Reports Server (NTRS)

    Kreidler, Eric R.; Bhallamudi, Vidya Praveen

    2001-01-01

    Three methods for applying ceramic coatings to wires were examined in depth and a fourth (chemical vapor deposition) was studied briefly. CVD coatings were not reported in the thesis because it was realized early in the study that the deposition rate of the coatings was too slow to be used in a commercial process. Of the methods reported in the thesis, slurry coating was the most promising. This method consists of slowly drawing a platinum wire through a thixotropic slurry of alumina in a vehicle composed of polyvinyl butyral, methyl ethyl ketone, and toluene. The coatings produced by this method were continuous and free of cracks after sintering. The sintered coatings crack when the wire is bent around sharp corners, but most of the coating remains in place and still provides electrical insulation between the wire and any metallic structure to which the wire may be attached. The coating thickness was 0.61 mm (16 micrometers). The electrical resistivity of the intact coating was 340 M-Ohm-cm at 800 C and 23 M-Ohm-cm at 1050 C. Therefore, these coatings more than meet the electrical requirements for use in turbine engines. Although adherence of the coating to the wire was generally excellent, a problem was noted in localized areas where the coating flaked off. Further work will be needed to obtain good coating adherence along the entire length of the wire. The next most promising coatings were made by electrophoretic deposition (EPD) of Al2O3 onto platinum wires, using mixtures of ethanol and acetone as the suspending liquid. These EPD coatings were made only on short lengths of wire because the coating is too fragile to allow spooling of the wire. The worst coatings were those made by electrophoretic deposition from aqueous suspensions. Continuous slurry coating of wire was achieved, but due to lack of suitable equipment, the wire had to be cut into short lengths for sintering.

  10. Metal{Polymer Hybrid Materials For Flexible Transparent Conductors

    NASA Astrophysics Data System (ADS)

    Narayanan, Sudarshan

    The field of organic electronics, till recently a mere research topic, is currently making rapid strides and tremendous progress into entering the mainstream electronics industry with several applications and products such as OLED televisions, curved displays, wearable devices, flexible solar cells, etc. already having been commercialized. A major component in these devices, especially for photovoltaic applications, is a transparent conductor used as one of the electrodes, which in most commercial applications are highly doped wide bandgap semiconducting oxides also called Transparent Conducting Oxides (TCOs). However, TCOs exhibit inherent disadvantages such as limited supply, brittle mechanical properties, expensive processing that present major barriers for the more widespread economic use in applications such as exible transparent conductors, owing to which suitable alternative materials are being sought. In this context we present two approaches in realizing alternative TCs using metal-polymer hybrid materials, with high figures of merit that are easily processable, reasonably inexpensive and mechanically robust as well. In this context, our first approach employs laminated metal-polymer photonic bandgap structures to effectively tune optical and electrical properties by an appropriate design of the material stack, factoring in the effect of the materials involved, the number of layers and layer properties. We have found that in the case of a four-bilayer Au/polystyrene (AujPS) laminate structure, an enhancement in optical transmittance of ˜ 500% in comparison to a monolithic A film of equivalent thickness, can be achieved. The high conductivity (˜ 106 O--1cm--1) of the metallic component, Au in this case, also ensures planar conductivity; metallic inclusions in the dielectric polymer layer can in principle give rise to out-of-plane conductivity as well enabling a fully functional TC. Such materials also have immense potential for several other applications

  11. Multiwire conductor having increased interwire resistance and good mechanical stability and method for making same

    DOEpatents

    Luhman, Thomas; Klamut, Carl

    1984-02-14

    An improved multiwire conductor of the type which is mechanically stabilized by a solder filler. A solder filled conductor is heated to a temperature sufficient to make the solder brittle, but below the melting point of the solder. While still hot, the conductor is flexed, causing the solder to separate from the wires comprising the conductor, thereby increasing the interwire resistance. In one embodiment the conductor may be heated to a temperature above the eutectic temperature of the solder so that a controlled amount of solder is removed. The subject invention is particularly suited for use with braided, ribbon-type, solder filled superconductors.

  12. Multiwire conductor having increased interwire resistance and good mechanical stability and method for making same

    DOEpatents

    Luhman, T.; Klamut, C.

    1982-03-15

    An improved multiwire conductor of the type which is mechanically stabilized by a solder filler. A solder filled conductor is heated to a temperature sufficient to make the solder brittle, but below the melting point of the solder. While still hot, the conductor is flexed, causing the solder to separate from the wires comprising the conductor, thereby increasing the interwire resistance. In one embodiment the conductor may be heated to a temperature above the eutectic temperature of the solder so that a controlled amount of solder is removed. The subject invention is particularly suited for use with braided, ribbon-type, solder filled superconductors.

  13. Multiwire conductor having greatly increased interwire resistance and method for making same

    DOEpatents

    Luhman, T.; Suenaga, M.

    1982-03-15

    An improved multiwire conductor of the type which is mechanically stabilized by a tin based solder filler is described. A solder filled conductor is heated to a temperature above its melting point for a period long enough to allow a substantial amount of copper to be dissolved from the wires comprising the conductor. The copper forms the brittle intermetallic compound Cu/sub 5/Sn/sub 6/ with tin in the solder. After cooling the conductor is flexed causing a random cracking of the solder, and thereby increasing the interwire resistance of the conductor. The subject invention is particularly adapted for use with braided, ribbon-type solder filled superconductors.

  14. Multiwire conductor having greatly increased interwire resistance and method for making same

    DOEpatents

    Luhman, Thomas; Suenaga, Masaki

    1984-01-17

    An improved multiwire conductor of the type which is mechanically stabilized by a tin based solder filler. A solder filled conductor is heated to a temperature above its melting point for a period long enough to allow a substantial amount of copper to be dissolved from the wires comprising the conductor. The copper forms the brittle intermetallic compound Cu.sub.5 Sn.sub.6 with tin in the solder. After cooling the conductor is flexed causing a random cracking of the solder, and thereby increasing the interwire resistance of the conductor. The subject invention is particularly adapted for use with braided, ribbon-type solder filled superconductors.

  15. Study on Quench Protection of Coil Wound of Copper or Silver Stabilized YBCO Conductors

    NASA Astrophysics Data System (ADS)

    Tsukamoto, O.; Fu, Y.; Yoshida, H.; Furuse, M.

    2004-06-01

    We investigated necessary amount of copper or silver stabilizer added to YBCO conductor by numerical calculation to protect the conductor in a coil of dry windings from damages caused by quenches. The coil is assumed to be operated at 20K, 40K and 77K and hot-spot temperature of the conductor during energy dump sequence is calculated. The necessary amount of the stabilizer and overall conductor current density of the conductor including the stabilizer were calculated to suppress the hot spot temperature below a certain threshold depending on the operation temperature.

  16. Photoemissive coating

    NASA Technical Reports Server (NTRS)

    Gange, R. A.

    1972-01-01

    Polystyrene coating is applied to holographic storage tube substrate via glow discharge polymerization in an inert environment. After deposition of styrene coating, antimony and then cesium are added to produce photoemissive layer. Technique is utilized in preparing perfectly organized polymeric films useful as single-crystal membranes.

  17. Electrostatic separation for recycling conductors, semiconductors, and nonconductors from electronic waste.

    PubMed

    Xue, Mianqiang; Yan, Guoqing; Li, Jia; Xu, Zhenming

    2012-10-01

    Electrostatic separation has been widely used to separate conductors and nonconductors for recycling e-waste. However, the components of e-waste are complex, which can be classified as conductors, semiconductors, and nonconductors according to their conducting properties. In this work, we made a novel attempt to recover the mixtures containing conductors (copper), semiconductors (extrinsic silicon), and nonconductors (woven glass reinforced resin) by electrostatic separation. The results of binary mixtures separation show that the separation of conductor and nonconductor, semiconductor and nonconductor need a higher voltage level while the separation of conductor and semiconductor needs a higher roll speed. Furthermore, the semiconductor separation efficiency is more sensitive to the high voltage level and the roll speed than the conductor separation efficiency. An integrated process was proposed for the multiple mixtures separation. The separation efficiency of conductors and semiconductors can reach 82.5% and 88%, respectively. This study contributes to the efficient recycling of valuable resources from e-waste.

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

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Wu, Yu; Bruzzone, Pierluigi; Stepanov, Boris; Qin, Jinggang; Long, Feng

    2014-04-01

    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.

  19. A Testing Platform for Validation of Overhead Conductor Aging Models and Understanding Thermal Limits

    SciTech Connect

    Irminger, Philip; Starke, Michael R; Dimitrovski, Aleksandar D; Young II, Marcus Aaron; Rizy, D Tom; Stovall, John P; Overholt, Philip N

    2014-01-01

    Power system equipment manufacturers and researchers continue to experiment with novel overhead electric conductor designs that support better conductor performance and address congestion issues. To address the technology gap in testing these novel designs, Oak Ridge National Laboratory constructed the Powerline Conductor Accelerated Testing (PCAT) facility to evaluate the performance of novel overhead conductors in an accelerated fashion in a field environment. Additionally, PCAT has the capability to test advanced sensors and measurement methods for accessing overhead conductor performance and condition. Equipped with extensive measurement and monitoring devices, PCAT provides a platform to improve/validate conductor computer models and assess the performance of novel conductors. The PCAT facility and its testing capabilities are described in this paper.

  20. Regulatory Aspects of Coatings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter gives a history of the development and uses of edible coating regulations, detailed chapters on coating caracteristics, determination of coating properties, methods for making coatings, and discription of coating film formers (polysaccharieds, lipids, resins, proteins). The chapter also...

  1. Vacuum-surface flashover switch with cantilever conductors

    DOEpatents

    Caporaso, George J.; Sampayan, Stephen E.; Kirbie, Hugh C.

    2001-01-01

    A dielectric-wall linear accelerator is improved by a high-voltage, fast rise-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface.

  2. Bi-2212/Ag tape conductor and coil development

    SciTech Connect

    Albert, G.W.; Leung, E.M.; Zhou, R.; Salazar, K.V.

    1996-12-31

    This paper presents recent progress by Los Alamos National Laboratory/Superconductivity Technology Center (LANL/STC) and Lockheed Martin Corporation/Advanced Development Operations (LMQADO) Energy and Power Systems group to jointly develop and test high temperature superconductor coils for practical applications such as motors, generators, magnetic bearings, superconducting magnetic energy storage (SMES), MAGLEV trains, or electrical inductors. Critical currents of 105 A/cm{sup 2} have been achieved in a Bi-2212/Ag tape conductor using a patented Ag addition process to improve core morphology and uniformity. Results of testing to measure key conductor parameters are presented along with design and analysis details of a general-purpose multi-layer HTS coil.

  3. Sprayable Elastic Conductors Based on Block Copolymer Silver Nanoparticle Composites

    PubMed Central

    2015-01-01

    Block copolymer silver nanoparticle composite elastic conductors were fabricated through solution blow spinning and subsequent nanoparticle nucleation. The reported technique allows for conformal deposition onto nonplanar substrates. We additionally demonstrated the ability to tune the strain dependence of the electrical properties by adjusting nanoparticle precursor concentration or localized nanoparticle nucleation. The stretchable fiber mats were able to display electrical conductivity values as high as 2000 ± 200 S/cm with only a 12% increase in resistance after 400 cycles of 150% strain. Stretchable elastic conductors with similar and higher bulk conductivity have not achieved comparable stability of electrical properties. These unique electromechanical characteristics are primarily the result of structural changes during mechanical deformation. The versatility of this approach was demonstrated by constructing a stretchable light emitting diode circuit and a strain sensor on planar and nonplanar substrates. PMID:25491507

  4. Electrical magnetochiral anisotropy in a bulk chiral molecular conductor.

    PubMed

    Pop, Flavia; Auban-Senzier, Pascale; Canadell, Enric; Rikken, Geert L J A; Avarvari, Narcis

    2014-01-01

    So far, no effect of chirality on the electrical properties of bulk chiral conductors has been observed. Introduction of chiral information in tetrathiafulvalene precursors represents a powerful strategy towards the preparation of crystalline materials in which the combination of chirality and conducting properties might allow the observation of the electrical magnetochiral anisotropy effect. Here we report the synthesis by electrocrystallization of both enantiomers of a bulk chiral organic conductor based on an enantiopure tetrathiafulvalene derivative. The enantiomeric salts crystallize in enantiomorphic hexagonal space groups. Single crystal resistivity measurements show metallic behaviour for the enantiopure salts down to 40 K, in agreement with band structure calculations. We describe here the first experimental evidence of electrical magnetochiral anisotropy in these crystals, confirming the chiral character of charge transport in our molecular materials. PMID:24796572

  5. Non-stripe charge order in dimerized organic conductors

    NASA Astrophysics Data System (ADS)

    Mori, Takehiko

    2016-06-01

    This paper demonstrates charge order is important in dimerized β - and κ -phase organic conductors similar to the uniform θ - and α -phase conductors. Here the magnitude of the dimerization represents the deviation from the ideal triangular lattice in analogy with the anisotropy in the θ phase. Since the ratio of the intradimer transfer integral to the interdimer transfer integral is as large as ˜2.6 , these dimerized phases lead to a dimer Mott insulator, whereas the Coulomb repulsion is closer to the triangular lattice because the ratio of the intradimer Coulomb repulsion to the interdimer Coulomb repulsion is comparatively small (˜1.7 ). Accordingly, in the static-limit calculation, non-stripe charge order with threefold periodicity appears between the uniform and the stripe phases, and the analogy with the θ phase suggests the first-order nature of the metal-insulator transition.

  6. Physical and Electronic Isolation of Carbon Nanotube Conductors

    NASA Technical Reports Server (NTRS)

    OKeeffe, James; Biegel, Bryan (Technical Monitor)

    2001-01-01

    Multi-walled nanotubes are proposed as a method to electrically and physically isolate nanoscale conductors from their surroundings. We use tight binding (TB) and density functional theory (DFT) to simulate the effects of an external electric field on multi-wall nanotubes. Two categories of multi-wall nanotube are investigated, those with metallic and semiconducting outer shells. In the metallic case, simulations show that the outer wall effectively screens the inner core from an applied electric field. This offers the ability to reduce crosstalk between nanotube conductors. A semiconducting outer shell is found not to perturb an electric field incident on the inner core, thereby providing physical isolation while allowing the tube to remain electrically coupled to its surroundings.

  7. Magnetic flux-trapping experiment with a moving conductor.

    PubMed

    Hovorka, J

    1969-11-14

    An aluminum conductor moving into and out of a magnetic field of 75 gauss traps within itself for varying lengths of time a detectable fraction of the encountered flux, which subsequently decays. A time constant of about 0.005 second, which is the order of magnitude predicted by classical electrodynamics, is measured. The result is of interest in connection with the "frozen-in field" concept of Babcock's sunspot model.

  8. Effects of particle size distribution in thick film conductors

    NASA Technical Reports Server (NTRS)

    Vest, R. W.

    1983-01-01

    Studies of particle size distribution in thick film conductors are discussed. The distribution of particle sizes does have an effect on fired film density but the effect is not always positive. A proper distribution of sizes is necessary, and while the theoretical models can serve as guides to selecting this proper distribution, improved densities can be achieved by empirical variations from the predictions of the models.

  9. Study, selection, and preparation of solid cationic conductors

    NASA Technical Reports Server (NTRS)

    Roth, W. L.; Mitoff, S. P.; King, R. N.

    1972-01-01

    Crystal chemical principles and transport theory were used to predict structures and specific compounds which might find application as solid electrolytes in rechargeable high energy and high power density batteries operating at temperatures less than 200 C. More than twenty compounds were synthesized or obtained and screened by nuclear magnetic resonance and conductivity. Many were densified by sintering or hot pressing. Encouraging results were obtained for nine of these materials but none have yet been good ionic conductors at low temperature.

  10. Electrostatic forces on two almost touching nonspherical charged conductors

    NASA Astrophysics Data System (ADS)

    Khair, Aditya S.

    2013-10-01

    Analytical expressions are derived for the electrostatic forces on two almost touching nonspherical conductors held at unequal voltages or carrying dissimilar charges in an insulating medium. Each conductor is a body of revolution whose surface is defined by the equation rn+zn=an, where r and z are radial and axial cylindrical co-ordinates, respectively, 2a is the equatorial width, and n is a parameter that controls the particle shape. The two objects are of identical shape and placed in a coaxial configuration, in which case the electrostatic forces are solely along their line of centers. The calculation of the forces is performed via a local analysis of the electrostatics in the thin gap region separating the particles. At a fixed potential difference, the magnitude of the attractive force F on the particles scales with the minimum gap height h0 as F ˜h02(1/n-1) for n > 1 and F ˜ln h0 for n = 1, to leading order as h0/a→0. The force increases as the gap region becomes flatter (increasing n), due to the intense electric field in the gap acting over a larger surface area. The opposite is found for particles carrying fixed charges: here, F ˜h0-2/n for n > 2 and F ˜h0-1[ln(a/h0)]-2 for n = 2. In this case, the potential difference between the conductors diminishes as the gap region becomes flatter, which overpowers the increase in gap area. Our results demonstrate that like-charge attraction occurs for a broad class of nonspherical conductors at close separations. The predicted sensitivity of the electrostatic force to particle shape is relevant to probe-based microscopy: specifically, to quantify the influence of tip-geometry on the force experienced by a charged probe near a conducting surface.

  11. Design principles for solid-state lithium superionic conductors.

    PubMed

    Wang, Yan; Richards, William Davidson; Ong, Shyue Ping; Miara, Lincoln J; Kim, Jae Chul; Mo, Yifei; Ceder, Gerbrand

    2015-10-01

    Lithium solid electrolytes can potentially address two key limitations of the organic electrolytes used in today's lithium-ion batteries, namely, their flammability and limited electrochemical stability. However, achieving a Li(+) conductivity in the solid state comparable to existing liquid electrolytes (>1 mS cm(-1)) is particularly challenging. In this work, we reveal a fundamental relationship between anion packing and ionic transport in fast Li-conducting materials and expose the desirable structural attributes of good Li-ion conductors. We find that an underlying body-centred cubic-like anion framework, which allows direct Li hops between adjacent tetrahedral sites, is most desirable for achieving high ionic conductivity, and that indeed this anion arrangement is present in several known fast Li-conducting materials and other fast ion conductors. These findings provide important insight towards the understanding of ionic transport in Li-ion conductors and serve as design principles for future discovery and design of improved electrolytes for Li-ion batteries. PMID:26280225

  12. Quaternized graphene oxide nanocomposites as fast hydroxide conductors.

    PubMed

    Zarrin, Hadis; Fu, Jing; Jiang, Gaopeng; Yoo, Skylar; Lenos, Jared; Fowler, Michael; Chen, Zhongwei

    2015-02-24

    Nanocomposites play a key role in performance improvements of hydroxide conductors employed in a wide range of alkaline-electrochemical systems such as fuel cells and metal-air batteries. Graphene oxide (GO) nanosheets are considered to be outstanding nanofillers for polymeric nanocomposites on account of their excellent physicochemical strength and electrochemical properties. In this work, a fast hydroxide conductor was developed on the basis of a chemically modified GO nanocomposite membrane. The high surface area of GO was functionalized with highly stable hydroxide-conductive groups using a dimethyloctadecyl [3-(trimethoxysilyl)propyl]ammonium chloride (DMAOP) precursor, named QAFGO, and then composed with porous polybenzimidazole PBI (pPBI) as a well-suited polymeric backbone. The nanocomposite exhibited outstanding hydroxide conductivity of 0.085 S cm(-1), high physicochemical strength, and electrochemical stability for 21 days. An alkaline fuel cell (AFC) setup was fabricated to determine the functionality of QAFGO/pPBI nanocomposite in an alkaline-based system. The high AFC performance with peak power density of 86.68 mW cm(-2) demonstrated that QAFGO/pPBI nanocomposite membrane has promising potential to be employed as a reliable hydroxide conductor for electrochemical systems working in alkaline conditions. PMID:25644712

  13. Design principles for solid-state lithium superionic conductors

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Richards, William Davidson; Ong, Shyue Ping; Miara, Lincoln J.; Kim, Jae Chul; Mo, Yifei; Ceder, Gerbrand

    2015-10-01

    Lithium solid electrolytes can potentially address two key limitations of the organic electrolytes used in today's lithium-ion batteries, namely, their flammability and limited electrochemical stability. However, achieving a Li+ conductivity in the solid state comparable to existing liquid electrolytes (>1 mS cm-1) is particularly challenging. In this work, we reveal a fundamental relationship between anion packing and ionic transport in fast Li-conducting materials and expose the desirable structural attributes of good Li-ion conductors. We find that an underlying body-centred cubic-like anion framework, which allows direct Li hops between adjacent tetrahedral sites, is most desirable for achieving high ionic conductivity, and that indeed this anion arrangement is present in several known fast Li-conducting materials and other fast ion conductors. These findings provide important insight towards the understanding of ionic transport in Li-ion conductors and serve as design principles for future discovery and design of improved electrolytes for Li-ion batteries.

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

    SciTech Connect

    ROSENTHAL,STEPHEN E.; DESJARLAIS,MICHAEL P.; SPIELMAN,RICK B.; STYGAR,WILLIAM A.; ASAY,JAMES R.; DOUGLAS,M.R.; HALL,C.A.; FRESE,M.H.; MORSE,R.L.; REISMAN,D.B.

    2000-08-29

    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.

  15. Protective Coating

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Inorganic Coatings, Inc.'s K-Zinc 531 protective coating is water-based non-toxic, non-flammable and has no organic emissions. High ratio silicate formula bonds to steel, and in 30 minutes, creates a very hard ceramic finish with superior adhesion and abrasion resistance. Improved technology allows application over a minimal commercial sandblast, fast drying in high humidity conditions and compatibility with both solvent and water-based topcoats. Coating is easy to apply and provides long term protection with a single application. Zinc rich coating with water-based potassium silicate binder offers cost advantages in materials, labor hours per application, and fewer applications over a given time span.

  16. The Conductor-Dielectric Junctions in a Low Density Plasma

    NASA Technical Reports Server (NTRS)

    Vayner, Boris; Galofaro, Joel; Ferguson, Dale; deGroot, Wim; Thomson, Clint; Dennison, J. R.; Davies, Robert

    1999-01-01

    A conductor-dielectric junction exposed to the space environment is a frequent spacecraft design feature. Due to spacecraft charging and/or solar array operation, the conductor can acquire a high potential with respect to the surrounding plasma. If this potential is positive the insulators adjacent to exposed conductors can collect current as if they were conductors themselves. This phenomenon, called snapover, results in a substantial increase in current collection, and may even result in a glow discharge if the potential is high enough. If a conductor has a negative potential, arcing can occur at the site of a junction. Both of these phenomena negatively affect spacecraft operation. To prevent negative consequences, the physical mechanisms of snapover and arc inception require investigation. In this paper, results are presented of an experimental and theoretical study of snapover, glow discharge, and arc phenomena for different materials immersed in argon or xenon plasmas. The effect of snapover is investigated for several metal-dielectric junctions: copper-teflon, copper-Kapton, copper-glass, aluminum-teflon, aluminum-Kapton, steel-teflon, anodized aluminum with pinholes, and copper-ceramics. I-V curves are measured and snapover inception voltages, essential parameters (increase in current and collection area due to secondary electrons), and glow discharge inception thresholds are determined. Optical spectra are obtained for glow discharges in both argon and xenon plasmas. These spectra provide information regarding atomic species entrapped in the glow region. Some spectral lines can be used to estimate plasma parameters in the discharge area. A video-camera and linear array were used to confirm that snapover inception is accompanied by very low intensity visible light emission. This result seems to be important for the estimate of the light pollution around spacecraft. Optical spectra (wavelengths 380-650 nm) of arcs are also obtained on a negatively biased

  17. Preparation of biaxially cube textured Cu substrate tapes for HTS coated conductor applications

    NASA Astrophysics Data System (ADS)

    Piñol, S.; Díaz, J.; Segarra, M.; Espiell, F.

    2001-01-01

    Cube textured copper tapes have been prepared as possible substrates for deposition of high critical current density YBCO films with intermediate metallic or ceramic biaxially textured buffer layers. The cube texture was promoted by recrystallization after cold rolling. The deformation degree, the effect of deformation reduction at each pass and the influence of annealing temperature on the recrystallization process has been studied. Different parameters have been optimized in order to obtain the sharpest cube texture {100}<001>. The full width half-maximum mean values (FWHM) of the grains out-of-plane measured from rocking curves in the parallel and perpendicular directions to the rolling are 10° and 14°, respectively, while the in-plane FWHM obtained from the pole figures is 10°.

  18. Effect of Interim Annealing on Mechanical Strength of TFA-MOD Derived YBCO Coated Conductors

    NASA Astrophysics Data System (ADS)

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

    TFA-MOD derived YBCO tapes are expected for many applications due to cost-efficiency. In some applications, uniformity and mechanical strength are required for tapes. A 205 m-long YBCO tape was fabricated with high and uniform Ic performance throughout the tape by adopting the interim annealing before the conversion process. The effect of the interim annealing on the crystal growth mechanism of YBCO has been studied focusing on the relationship between the interim annealing conditions and delamination, in this work. Delamination strength was evaluated in the samples prepared with and without interim annealing by the stud pull method. Measurements were carried out on 50 different points for each sample and the results were analyzed statistically. The difference between the two samples was remarkably seen in the delamination strength below 60 MPa. The conventionally annealed sample had more points with low delamination strength below 60 MPa than the interim annealed one. The cross sectional images of both samples observed by SEM showed that there were few pores within the interim annealed superconducting layer, although conventional superconducting layer had many pores. These results suggest that the pores within YBCO layer might be origins to be propagated for delamination at low strength.

  19. Resputtering effect during MgO buffer layer deposition by magnetron sputtering for superconducting coated conductors

    SciTech Connect

    Xiao, Shaozhu; Shi, Kai; Deng, Shutong; Han, Zhenghe; Feng, Feng Lu, Hongyuan; Qu, Timing; Zhu, Yuping; Huang, Rongxia

    2015-07-15

    In this study, MgO thin films were deposited by radio-frequency magnetron sputtering. The film thickness in the deposition area directly facing the target center obviously decreased compared with that in other areas. This reduction in thickness could be attributed to the resputtering effect resulting from bombardment by energetic particles mainly comprising oxygen atoms and negative oxygen ions. The influences of deposition position and sputtering pressure on the deposition rate were investigated. Resputtering altered the orientation of the MgO film from (111) to (001) when the film was deposited on a single crystal yttria-stabilized zirconia substrate. The density distribution of energetic particles was calculated on the basis of the measured thicknesses of the MgO films deposited at different positions. The divergence angle of the energetic particle flux was estimated to be approximately 15°. The energetic particle flux might be similar to the assisting ion flux in the ion beam assisted deposition process and could affect the orientation of the MgO film growth.

  20. High rate buffer layer for IBAD MgO coated conductors

    DOEpatents

    Foltyn, Stephen R.; Jia, Quanxi; Arendt, Paul N.

    2007-08-21

    Articles are provided including a base substrate having a layer of an oriented material thereon, and, a layer of hafnium oxide upon the layer of an oriented material. The layer of hafnium oxide can further include a secondary oxide such as cerium oxide, yttrium oxide, lanthanum oxide, scandium oxide, calcium oxide and magnesium oxide. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of hafnium oxide or layer of hafnium oxide and secondary oxide.

  1. Self-fields in thin superconducting tapes: Implications for the thickness effect in coated conductors

    SciTech Connect

    Sanchez, Alvaro; Navau, Carles; Del-Valle, Nuria; Chen, Du-Xing; Clem, John R.

    2010-02-18

    A large decrease in transport current density has been observed in high-temperature superconducting films for increasing film thickness. In this work we theoretically explain the nature and the ubiquitous presence of this so-called thickness effect by analyzing the self-field created by the transport currents in the superconductor, assuming a realistic field-dependent critical-current density J{sub c}. This knowledge can help in finding ways to improve transport current in superconducting films.

  2. Life cycle cost study for coated conductor manufacture by metal organic chemical vapor deposition

    SciTech Connect

    Chapman, J.N.

    1999-07-13

    The purpose of this report is to calculate the cost of producing high temperature superconducting wire by the Metal Organic Chemical Vapor Deposition (MOCVD) process. The technology status is reviewed from the literature and a plant conceptual design is assumed for the cost calculation. The critical issues discussed are the high cost of the metal organic precursors, the material utilization efficiency and the capability of the final product as measured by the critical current density achieved. Capital, operating and material costs are estimated and summed as the basis for calculating the cost per unit length of wire. Sensitivity analyses of key assumptions are examined to determine their effects on the final wire cost. Additionally, the cost of wire on the basis of cost per kiloampere per meter is calculated for operation at lower temperatures than the liquid nitrogen boiling temperature. It is concluded that this process should not be ruled out on the basis of high cost of precursors alone.

  3. AC over-current characteristics of YBCO coated conductor with copper stabilizer layer considering insulation layer

    NASA Astrophysics Data System (ADS)

    Du, H.-I.; Kim, M.-J.; Kim, Y.-J.; Lee, D.-H.; Han, B.-S.; Song, S.-S.

    2010-11-01

    Compared with the first-generation BSCCO wire, the YBCO thin-film wire boasts low material costs and high Jc and superior magnetic-field properties, among other strengths. Meanwhile, the previous BSCCO wire material for superconducting cables has been researched on considerably with regard to its post-wire quenching characteristics during the application of an alternating over-current. In this regard, the promising YBCO thin-film wire has yet to be further researched on. Moreover, still lacking is research on the YBCO thin-film wire with insulating layers, which is essential in the manufacture of superconducting cables, along with the testing of the application of an alternating over-current to the wire. In this study, YBCO thin-film wires with copper-stabilizing layers were used in testing alternating over-current application according to the presence or absence of insulating layers and to the thickness of such layers, to examine the post-quenching wire resistance increase and quenching trends. The YBCO thin-film wire with copper-stabilizing layers has a critical temperature of 90 K and a critical current of 85 A rms. Moreover, its current application cycle is 5.5 cycles, and its applied currents are 354, 517, 712, and 915 A peak. These figures enabled the YBCO thin-film wires with copper-stabilizing layers to reach 90, 180, 250, and 300 K, respectively, in this study. These temperatures serve as a relative reference to examine the post-quenching wire properties following the application of an alternating over-current.

  4. Electrodeposited Ag-Stabilization Layer for High Temperature Superconducting Coated Conductors: Preprint

    SciTech Connect

    Bhattacharya, R. N.; Mann, J.; Qiao, Y.; Zhang, Y.; Selvamanickam, V.

    2010-11-01

    We developed a non-aqueous based electrodepostion process of Ag-stabilization layer on YBCO superconductor tapes. The non-aqueous electroplating solution is non-reactive to the HTS layer thus does not detoriate the critical current capability of the superconductor layer when plated directly on the HTS tape. The superconducting current capabilities of these tapes were measured by non-contact magnetic measurements.

  5. Double disordered YBCO coated conductors of industrial scale: high currents in high magnetic field

    NASA Astrophysics Data System (ADS)

    Abraimov, D.; Ballarino, A.; Barth, C.; Bottura, L.; Dietrich, R.; Francis, A.; Jaroszynski, J.; Majkic, G. S.; McCallister, J.; Polyanskii, A.; Rossi, L.; Rutt, A.; Santos, M.; Schlenga, K.; Selvamanickam, V.; Senatore, C.; Usoskin, A.; Viouchkov, Y. L.

    2015-11-01

    A significant increase of critical current in high magnetic field, up to 31 T, was recorded in long tapes manufactured by employing a double-disorder route. In a double-disordered high-temperature superconductor (HTS), a superimposing of intrinsic and extrinsic disorder takes place in a way that (i) the intrinsic disorder is caused by local stoichiometry deviations that lead to defects of crystallinity that serve as pining centers in the YBa2Cu3O x-δ matrix and (ii) the extrinsic disorder is introduced via embedded atoms or particles of foreign material (e.g. barium zirconate), which create a set of lattice defects. We analyzed possible technological reasons for this current gain. The properties of these tapes over a wider field-temperature range as well as field anisotropy were also studied. Record values of critical current as high as 309 A at 31 T, 500 A at 18 Tm and 1200 A at 5 T were found in 4 mm wide tape at 4.2 K and B perpendicular to tape surface. HTS layers were processed in medium-scale equipment that allows a maximum batch length of 250 m while 22 m long batches were provided for investigation. Abnormally high ratios (up to 10) of critical current density measured at 4.2 K, 19 T to critical current density measured at 77 K, self-field were observed in tapes with the highest in-field critical current. Anisotropy of the critical current as well as angular dependences of n and α values were investigated. The temperature dependence of critical current is presented for temperatures between 4.2 and 40 K. Prospects for the suppression of the dog-bone effect by Cu plating and upscale of processing chain to >500 m piece length are discussed.

  6. Vertically aligned gas-insulated transmission line having particle traps at the inner conductor

    DOEpatents

    Dale, Steinar J.

    1984-01-01

    Gas insulated electrical apparatus having first and second conductors separated by an insulating support within an insulating gas environment, and particle traps disposed along the surface of the high potential conductor for trapping and inactivating foreign particles which may be present within the insulating gas medium. Several embodiments of the invention were developed which are particularly suited for vertically aligned gas insulated transmission lines. The particle traps are grooves or cavities formed into the walls of the tubular inner conductor, without extending into the hollow portion of the conductor. In other embodiments, the traps are appendages or insert flanges extending from the inner conductor, with the insulator supports contacting the appendages instead of the inner conductor.

  7. Manufacture of the hollow supercritical He cooled conductor for the ECN/Sultan project

    SciTech Connect

    Franken, W.; de Vries, A.; de Winter, T.; ter Beeke, H.; Brieko, M.; Strauss, B.; Torrey, S.

    1983-05-01

    This paper describes the manufacturing process for the conductor used in the ECN contribution to the Sultan project. This conductor which is cooled by forced flow supercritical helium is composed of a 16 strand Rutherford Cable continuously soldered to a rectangular copper tube. The requirements of the magnet design criteria on the choice of materials and manufacturing methods is discussed. In particular the final manufacturing method of joining the conductors by a ''continuous casting'' process is described in detail.

  8. Scattering by a perfect electromagnetic conductor (PEMC) plate embedded in lossy medium

    NASA Astrophysics Data System (ADS)

    Ahmed, Saeed; Khalid Khan, Muhammad; Rehman, Atta Ur

    2016-07-01

    In this article, we develop an analytic theory for a perfect electromagnetic conductor (PEMC) plate embedded in lossy medium. The duality transformation introduced by Lindell and Sihvola is applied to study the electromagnetic wave scattering by a PEMC plate. Perfect electric conductor and perfect magnetic conductor are the limiting cases of PEMC media. Here, we study monoscattering by PEMC plate embedded in four different soil models. Numerical results are discussed and compared with the available literature.

  9. Semi-flexible gas-insulated transmission line using protection tube in conductor plug-in joint

    DOEpatents

    Kommineni, Prasad R.

    1983-01-25

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. A plug and socket arrangement is utilized for joining adjacent sections of the inner conductor, and a protection tube is utilized inside the hollow plug to maintain proper alignment of the joint when the transmission line is bent.

  10. Semi-flexible gas-insulated transmission line using protection tube in conductor plug-in joint

    DOEpatents

    Kommineni, P.R.

    1983-01-25

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. A plug and socket arrangement is utilized for joining adjacent sections of the inner conductor, and a protection tube is utilized inside the hollow plug to maintain proper alignment of the joint when the transmission line is bent. 3 figs.

  11. Conductor and joint test results of JT-60SA CS and EF coils using the NIFS test facility

    NASA Astrophysics Data System (ADS)

    Obana, Tetsuhiro; Takahata, Kazuya; Hamaguchi, Shinji; Kizu, Kaname; Murakami, Haruyuki; Chikaraishi, Hirotaka; Noguchi, Hiroki; Kobuchi, Takashi; Moriuchi, Sadatomo; Imagawa, Shinsaku; Mito, Toshiyuki; Tsuchiya, Katsuhiko; Natsume, Kyohei; Yoshida, Kiyoshi; Nomoto, Kazuhiro; Kim, Tae-hyun

    2016-01-01

    In 2007, JAEA and NIFS launched the test project to evaluate the performance of cable-in-conduit (CIC) conductors and conductor joints for the JT-60SA CS and EF coils. In this project, conductor tests for four types of coil conductor and joint tests for seven types of conductor joint have been conducted for the past eight years using the NIFS test facility. As a result, the test project indicated that the CIC conductors and conductor joints fulfill the design requirement for the CS and EF coils. In addition, the NIFS test facility is expected to be utilized as the test facility for the development of a conductor and conductor joint for the purpose of the DEMO nuclear fusion power plant, provided that the required magnetic field strength is within 9 T.

  12. Analytical model for the dynamic resistivity of electrically-exploded conductors

    SciTech Connect

    Lee, R.S.

    1986-10-10

    A detailed model for the dynamic resistivity of an exploding conductor presents many difficulties. An electrically-exploded conductor undergoes significant hydrodynamic expansion as it is heated. Resistivity is a function of both the temperature and density of a conductor and realistic models for resistivity over the range of parameter space experienced by an exploding conductor are quite complex. See for example, the model of Lee and More (1984). Calculation of the hydrodynamic expansion of the conductor during and subsequent to the explosion is likewise dependent on detailed knowledge of the equation of state for the conductor in a range where few experimental data exist. A further complication is the strong magnetic field which couples the hydrodynamic expansion to the currents flowing in the expanding material. In spite of the difficulties, progress is being made on detailed modeling of fuses and exploding conductors (Lidemuth and co-workers, 1985). A simpler approach has proved to be quite useful for modeling the electrical behavior of exploding bridgewire and slapper detonators and for modeling the explosionss of large conductors exploded with large capacitor banks. In the work described here, a simple, empirical model was developed which can be expressed as a closed-form algebraic expression involving four parameters. This model has been used in a computer code which will calculate the burst times and burst currents for up to 15 conductors exploded in series in a capacitor-discharge circuit.

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

    NASA Astrophysics Data System (ADS)

    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.

  14. High temperature superconducting composite conductor and method for manufacturing the same

    DOEpatents

    Holesinger, Terry G.; Bingert, John F.

    2002-01-01

    A high temperature superconducting composite conductor is provided including a high temperature superconducting material surrounded by a noble metal layer, the high temperature superconducting composite conductor characterized as having a fill factor of greater than about 40. Additionally, the conductor can be further characterized as containing multiple cores of high temperature superconducting material surrounded by a noble metal layer, said multiple cores characterized as having substantially uniform geometry in the cross-sectional dimensions. Processes of forming such a high temperature superconducting composite conductor are also provided.

  15. Formation of 2D nanoparticles with block structure in simultaneous electric explosion of conductors

    SciTech Connect

    Kryzhevich, Dmitrij S. E-mail: kost@ispms.ru; Zolnikov, Konstantin P. E-mail: kost@ispms.ru; Abdrashitov, Andrei V.; Lerner, Marat I.; Psakhie, Sergey G.

    2014-11-14

    A molecular dynamics simulation of nanoparticle formation in simultaneous electric explosion of conductors is performed. Interatomic interaction is described using potentials calculated in the framework of the embedded atom method. High-rate heating results in failure of the conductors with the formation of nanoparticles. The influence of the heating rate, temperature distribution over the specimen cross-section and the distance between simultaneously exploded conductors on the structure of formed nanoparticles is studied. The calculation results show that the electric explosion of conductors allows the formation of nanoparticles with block structure.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Nanostructured Coatings

    NASA Astrophysics Data System (ADS)

    Rivière, J.-P.

    In many branches of technology where surfaces are playing a growing role, the use of coatings is often the only way to provide surfaces with specific functional properties. For example, the austenitic stainless steels or titanium alloys exhibit poor resistance to wear and low hardness values, which limits the field of applications. The idea then is to develop new solutions which would improve the mechanical performance and durability of objects used in contact and subjected to mechanical forces in hostile gaseous or liquid environments. Hard coatings are generally much sought after to enhance the resistance to wear and corrosion. They are of particular importance because they constitute a class of protective coatings which is already widely used on an industrial scale to improve the hardness and lifetime of cutting tools.

  18. Protective Coatings

    NASA Technical Reports Server (NTRS)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  19. Numerical study on the mechanisms of the SERS of gold-coated pyramidal tip substrates

    NASA Astrophysics Data System (ADS)

    Li, Rui; Wang, Qiao; Li, Hong; Liu, Kun; Pan, Shi; Zhan, Weishen; Chen, Maodu

    2016-06-01

    In this paper, the physical enhancement mechanisms of the surface-enhanced Raman scattering (SERS) of pyramidal tip substrates are studied theoretically. We structure the periodic square-based arrays of adjacent nanometer pyramidal gold-coated tips on silicon. In order to determine the contribution of plasmonic or diffraction effects on the SERS, three-dimensional (3D) numerical simulations are implemented by taking into account the substrate coated with a gold thin film or a perfect electrical conductor thin film. The tip distance, metal coating thickness and incident light polarization angle are also optimized to investigate whether the further SERS signal can be enhanced.

  20. Gold Coating

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Epner Technology Inc. responded to a need from Goddard Space Flight Center for the ultimate in electroplated reflectivity needed for the Mars Global Surveyor Mars Orbiter Laser Altimeter (MOLA). Made of beryllium, the MOLA mirror was coated by Epner Technology Laser Gold process, specially improved for the project. Improved Laser Gold- coated reflectors have found use in an epitaxial reactor built for a large semiconductor manufacturer as well as the waveguide in Braun-Thermoscan tympanic thermometer and lasing cavities in various surgical instruments.

  1. Microstructure of Ice Accretions Grown on Aluminum Conductors.

    NASA Astrophysics Data System (ADS)

    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.

  2. Thermally Stable Super Ionic Conductor from Carbon Sphere Oxide.

    PubMed

    Islam, Md Saidul; Karim, Mohammad Razaul; Hatakeyama, Kazuto; Takehira, Hiroshi; Ohtani, Ryo; Nakamura, Masaaki; Koinuma, Michio; Hayami, Shinya

    2016-08-19

    A highly stable proton conductor has been developed from carbon sphere oxide (CSO). Carbon sphere (CS) generated from sucrose was oxidized successfully to CSO using Hummers' graphite oxidation technique. At room temperature and 90 % relative humidity, the proton conductivity of thin layer CSO on microsized comb electrode was found to be 8.7×10(-3)  S cm(-1) , which is higher than that for a similar graphene oxide (GO) sample (3.4×10(-3)  S cm(-1) ). The activation energy (Ea ) of 0.258 eV suggests that the proton is conducted through the Grotthuss mechanism. The carboxyl functional groups on the CSO surface are primarily responsible for transporting protons. In contrast to conventional carbon-based proton conductors, in which the functional groups decompose around 80 °C, CSO has a stable morphology and functional groups with reproducible proton conductivity up to 400 °C. Even once annealed at different temperatures at high relative humidity, the proton conductivity of CSO remains almost unchanged, whereas significant change is seen with a similar GO sample. After annealing at 100 and 200 °C, the respective proton conductivity of CSO was almost the same, and was about ∼50 % of the proton conductivity at room temperature. Carbon-based solid electrolyte with such high thermal stability and reproducible proton conductivity is desired for practical applications. We expect that a CSO-based proton conductor would be applicable for fuel cells and sensing devices operating under high temperatures. PMID:27411089

  3. Stretchable nanoparticle conductors with self-organized conductive pathways

    NASA Astrophysics Data System (ADS)

    Kim, Yoonseob; Zhu, Jian; Yeom, Bongjun; di Prima, Matthew; Su, Xianli; Kim, Jin-Gyu; Yoo, Seung Jo; Uher, Ctirad; Kotov, Nicholas A.

    2013-08-01

    Research in stretchable conductors is fuelled by diverse technological needs. Flexible electronics, neuroprosthetic and cardiostimulating implants, soft robotics and other curvilinear systems require materials with high conductivity over a tensile strain of 100 per cent (refs 1, 2, 3). Furthermore, implantable devices or stretchable displays need materials with conductivities a thousand times higher while retaining a strain of 100 per cent. However, the molecular mechanisms that operate during material deformation and stiffening make stretchability and conductivity fundamentally difficult properties to combine. The macroscale stretching of solids elongates chemical bonds, leading to the reduced overlap and delocalization of electronic orbitals. This conductivity-stretchability dilemma can be exemplified by liquid metals, in which conduction pathways are retained on large deformation but weak interatomic bonds lead to compromised strength. The best-known stretchable conductors use polymer matrices containing percolated networks of high-aspect-ratio nanometre-scale tubes or nanowires to address this dilemma to some extent. Further improvements have been achieved by using fillers (the conductive component) with increased aspect ratio, of all-metallic composition, or with specific alignment (the way the fillers are arranged in the matrix). However, the synthesis and separation of high-aspect-ratio fillers is challenging, stiffness increases with the volume content of metallic filler, and anisotropy increases with alignment. Pre-strained substrates, buckled microwires and three-dimensional microfluidic polymer networks have also been explored. Here we demonstrate stretchable conductors of polyurethane containing spherical nanoparticles deposited by either layer-by-layer assembly or vacuum-assisted flocculation. High conductivity and stretchability were observed in both composites despite the minimal aspect ratio of the nanoparticles. These materials also demonstrate the

  4. One-step preparation of transparent superhydrophobic coatings using atmospheric arc discharge

    NASA Astrophysics Data System (ADS)

    Li, Jian; Huang, Zhengyong; Wang, Feipeng; Yan, Xinzhu; Wei, Yuan

    2015-08-01

    In this letter, we report a fast, simple, and single step approach to the preparation of transparent super-hydrophobic coatings on a copper conductor via atmosphere pressure arc discharges. The preparation procedures, hydrophobic characteristics, anti-pollution capability, and transparency of the super-hydrophobic coating are presented. A dual micro- and nano-scale hierarchical structure is observed on the super-hydrophobic coating with a water contact angle greater than 150°. The coating is, thus, capable of removing a significant amount of contaminants with a small quantity of water droplets. Attenuated total reflection Fourier transform infrared spectroscopy indicates that hydrophobic methyl groups exist on the surface of the coating. The surface roughness measurement results prove that the super-hydrophobic surface obeys the Cassie-Baxter model and its light scattering is very weak. Results demonstrate the conceptual feasibility of production of optically transparent super-hydrophobic coating by arc spraying of polymers under the atmospheric pressure.

  5. Magnetophonon oscillations caused by acoustic phonons in bulk conductors

    NASA Astrophysics Data System (ADS)

    Raichev, O. E.

    2016-09-01

    The interaction of electrons with acoustic phonons under a magnetic field leads to a remarkable kind of magnetophonon oscillation of transport coefficients, recently discovered in two-dimensional electron systems. The present study shows that similar oscillations exist in bulk conductors and provides a theory of this phenomenon for the case of spherical Fermi surfaces. The resonance peaks occur when the product of the Fermi surface diameter by the sound velocity is a multiple of the cyclotron frequency. Theoretical predictions may facilitate the experimental observation of the phenomenon.

  6. Magnet and conductor developments for the Mirror Fusion Program

    SciTech Connect

    Cornish, D.N.

    1981-10-09

    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 Nb/sub 3/Sn 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.

  7. Non Equilibrium Quantum Transport in a model of molecular conductor

    NASA Astrophysics Data System (ADS)

    Schiro', Marco; Fabrizio, Michele

    2010-03-01

    We investigate non equilibrium effects in quantum transport through a simple model of molecular conductor where a single electronic level coupled to a vibrational mode is hybridized with biased metallic contacts. Using a recently developed numerical method [1] we compute the time dependent current and extract steady state properties such as I-V characteristic, differential conductance and phonon distribution function. We also discuss transient effects and comment on the onset of bistability in the strong coupling regime. [4pt] [1] M. Schiro', M. Fabrizio, Phys.Rev.B 79 153302 (2009)

  8. Composite mixed oxide ionic and electronic conductors for hydrogen separation

    DOEpatents

    Gopalan, Srikanth; Pal, Uday B.; Karthikeyan, Annamalai; Hengdong, Cui

    2009-09-15

    A mixed ionic and electronic conducting membrane includes a two-phase solid state ceramic composite, wherein the first phase comprises an oxygen ion conductor and the second phase comprises an n-type electronically conductive oxide, wherein the electronically conductive oxide is stable at an oxygen partial pressure as low as 10.sup.-20 atm and has an electronic conductivity of at least 1 S/cm. A hydrogen separation system and related methods using the mixed ionic and electronic conducting membrane are described.

  9. Method for deposition of a conductor in integrated circuits

    DOEpatents

    Creighton, J. Randall; Dominguez, Frank; Johnson, A. Wayne; Omstead, Thomas R.

    1997-01-01

    A method is described for fabricating integrated semiconductor circuits and, more particularly, for the selective deposition of a conductor onto a substrate employing a chemical vapor deposition process. By way of example, tungsten can be selectively deposited onto a silicon substrate. At the onset of loss of selectivity of deposition of tungsten onto the silicon substrate, the deposition process is interrupted and unwanted tungsten which has deposited on a mask layer with the silicon substrate can be removed employing a halogen etchant. Thereafter, a plurality of deposition/etch back cycles can be carried out to achieve a predetermined thickness of tungsten.

  10. Method for deposition of a conductor in integrated circuits

    DOEpatents

    Creighton, J.R.; Dominguez, F.; Johnson, A.W.; Omstead, T.R.

    1997-09-02

    A method is described for fabricating integrated semiconductor circuits and, more particularly, for the selective deposition of a conductor onto a substrate employing a chemical vapor deposition process. By way of example, tungsten can be selectively deposited onto a silicon substrate. At the onset of loss of selectivity of deposition of tungsten onto the silicon substrate, the deposition process is interrupted and unwanted tungsten which has deposited on a mask layer with the silicon substrate can be removed employing a halogen etchant. Thereafter, a plurality of deposition/etch back cycles can be carried out to achieve a predetermined thickness of tungsten. 2 figs.

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

    PubMed

    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.

  12. A dendrite-suppressing composite ion conductor from aramid nanofibres

    NASA Astrophysics Data System (ADS)

    Tung, Siu-On; Ho, Szushen; Yang, Ming; Zhang, Ruilin; Kotov, Nicholas A.

    2015-01-01

    Dendrite growth threatens the safety of batteries by piercing the ion-transporting separators between the cathode and anode. Finding a dendrite-suppressing material that combines high modulus and high ionic conductance has long been considered a major technological and materials science challenge. Here we demonstrate that these properties can be attained in a composite made from Kevlar-derived aramid nanofibres assembled in a layer-by-layer manner with poly(ethylene oxide). Importantly, the porosity of the membranes is smaller than the growth area of the dendrites so that aramid nanofibres eliminate ‘weak links’ where the dendrites pierce the membranes. The aramid nanofibre network suppresses poly(ethylene oxide) crystallization detrimental for ion transport, giving a composite that exhibits high modulus, ionic conductivity, flexibility, ion flux rates and thermal stability. Successful suppression of hard copper dendrites by the composite ion conductor at extreme discharge conditions is demonstrated, thereby providing a new approach for the materials engineering of solid ion conductors.

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Development of Jacketing Technologies for Iter CS and TF Conductor

    NASA Astrophysics Data System (ADS)

    Hamada, K.; Nakajima, H.; Matsui, K.; Kawano, K.; Takano, K.; Tsutsumi, F.; Okuno, K.; Teshima, O.; Soejima, K.

    2008-03-01

    The Japan Atomic Energy Agency (JAEA) has developed jacketing technologies for ITER Toroidal Field (TF) and Central Solenoid (CS) conductor. Full scale TF and CS conduits were fabricated using carbon-reduced SUS316LN and boron-added (˜40 ppm) high manganese stainless steel (0.025C -22Mn -13Cr -9Ni -0.12N: JK2LB), respectively. Welding condition was optimized so that back bead does not interfere a cable insertion. The weld joint samples were compacted by a compaction machine that was newly constructed and tested at 4.2 K. Mechanical characteristics at 4K of CS, TF conduits and CS welded joint satisfied ITER mechanical requirements. TF welded joint shows slightly lower value of 0.2% yield strength (885 MPa) than that of ITER requirement (900 MPa). The TF conduit contains nitrogen content of 0.14%, which is minimum value in ITER specification. The lower nitrogen content may be caused by the release of nitrogen from molten metal during non-filler welding resulting in a 4 K strength decrease. To satisfy the ITER requirements, minimum nitrogen contents of conduit should be increased from 0.14% to 0.15% at least. Therefore, JAEA successfully developed TF and CS conduits with welding technologies and finalized the procurement specification for ITER conductor jacketing.

  15. A dendrite-suppressing composite ion conductor from aramid nanofibres.

    PubMed

    Tung, Siu-On; Ho, Szushen; Yang, Ming; Zhang, Ruilin; Kotov, Nicholas A

    2015-01-27

    Dendrite growth threatens the safety of batteries by piercing the ion-transporting separators between the cathode and anode. Finding a dendrite-suppressing material that combines high modulus and high ionic conductance has long been considered a major technological and materials science challenge. Here we demonstrate that these properties can be attained in a composite made from Kevlar-derived aramid nanofibres assembled in a layer-by-layer manner with poly(ethylene oxide). Importantly, the porosity of the membranes is smaller than the growth area of the dendrites so that aramid nanofibres eliminate 'weak links' where the dendrites pierce the membranes. The aramid nanofibre network suppresses poly(ethylene oxide) crystallization detrimental for ion transport, giving a composite that exhibits high modulus, ionic conductivity, flexibility, ion flux rates and thermal stability. Successful suppression of hard copper dendrites by the composite ion conductor at extreme discharge conditions is demonstrated, thereby providing a new approach for the materials engineering of solid ion conductors.

  16. A dendrite-suppressing composite ion conductor from aramid nanofibres.

    PubMed

    Tung, Siu-On; Ho, Szushen; Yang, Ming; Zhang, Ruilin; Kotov, Nicholas A

    2015-01-01

    Dendrite growth threatens the safety of batteries by piercing the ion-transporting separators between the cathode and anode. Finding a dendrite-suppressing material that combines high modulus and high ionic conductance has long been considered a major technological and materials science challenge. Here we demonstrate that these properties can be attained in a composite made from Kevlar-derived aramid nanofibres assembled in a layer-by-layer manner with poly(ethylene oxide). Importantly, the porosity of the membranes is smaller than the growth area of the dendrites so that aramid nanofibres eliminate 'weak links' where the dendrites pierce the membranes. The aramid nanofibre network suppresses poly(ethylene oxide) crystallization detrimental for ion transport, giving a composite that exhibits high modulus, ionic conductivity, flexibility, ion flux rates and thermal stability. Successful suppression of hard copper dendrites by the composite ion conductor at extreme discharge conditions is demonstrated, thereby providing a new approach for the materials engineering of solid ion conductors. PMID:25626170

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

    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.

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

    PubMed Central

    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

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

    PubMed

    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. Amorphous carbon interlayers for gold on elastomer stretchable conductors

    NASA Astrophysics Data System (ADS)

    Manzoor, M. U.; Tuinea-Bobe, C. L.; McKavanagh, F.; Byrne, C. P.; Dixon, D.; Maguire, P. D.; Lemoine, P.

    2011-06-01

    Gold on polydimethylsiloxane (PDMS) stretchable conductors were prepared using a novel approach by interlacing an hydrogenated amorphous carbon (a-C : H) layer between the deposited metal layer and the elastomer. AFM analysis of the a-C : H film surface before gold deposition shows nanoscale buckling, the corresponding increase in specific surface area corresponds to a strain compensation for the first 4-6% of bi-axial tensile loading. Without this interlayer, the deposited gold films show much smaller and uni-directional ripples as well as more cracks and delaminations. With a-C : H interlayer, the initial electrical resistivity of the metal film decreases markedly (280-fold decrease to 8 × 10-6 Ω cm). This is not due to conduction within the carbon interlayer; both a-C : H/PDMS and PDMS substrates are electrically insulating. Upon cyclic tensile loading, both films become more resistive, but return to their initial state after 20 tensile cycles up to 60% strain. Profiling experiments using secondary ion mass spectroscopy and x-ray photoelectron spectroscopy indicate that the a-C : H layer intermixes with the PDMS, resulting in a graded layer of decreasing stiffness. We believe that both this graded layer and the surface buckling contribute to the observed improvement in the electrical performance of these stretchable conductors.

  1. Interacting Electrodynamics of Short Coherent Conductors in Quantum Circuits

    NASA Astrophysics Data System (ADS)

    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.

  2. Internal pressure effects in the AIRCO-LCT conductor sheath

    SciTech Connect

    Luton, J.N.; Clinard, J.A.; Lue, J.W.; Gray, W.H.; Summers, L.T.; Kershaw, R.

    1985-01-01

    The large Nb/sub 3/Sn superconducting test coil produced by Westinghouse Electric Corporation for the international Large Coil Task (LCT) utilizes a conductor composed of cabled multifilamentary strands immersed in flowing supercritical helium contained by a square structural sheath made of the high-strength stainless alloy JBX-75. Peak pressures of a few hundred atmospheres are predicted to occur during quench, and measurement of these pressures seems feasible only through penetrations of the sheath wall. Fully processed short lengths of conductor were taken from production ends, fitted with pressure taps and strain gauges, and pressurized with helium gas. Failure, at 1000 atm at liquid nitrogen temperature, was by a catastrophic splitting of the sheath at a corner. Strain measurements and burst pressure agreed with elastic-plastic finite element stress calculations made for the sheath alone. Neither the production seam weld nor the pressure tap penetrations or their fillet welds contributed to the failure, although the finite element calculations show that these areas were also highly stressed, and examination of the failed sample showed that the finite welds were of poor quality. Failure was by tensile overload, with no evidence of fatigue.

  3. Solution-solid-solid mechanism: superionic conductors catalyze nanowire growth.

    PubMed

    Wang, Junli; Chen, Kangmin; Gong, Ming; Xu, Bin; Yang, Qing

    2013-09-11

    The catalytic mechanism offers an efficient tool to produce crystalline semiconductor nanowires, in which the choice, state, and structure of catalysts are active research issues of much interest. Here we report a novel solution-solid-solid (SSS) mechanism for nanowire growth catalyzed by solid-phase superionic conductor nanocrystals in low-temperature solution. The preparation of Ag2Se-catalyzed ZnSe nanowires at 100-210 °C is exampled to elucidate the SSS model, which can be extendable to grow other II-VI semiconductor (e.g., CdSe, ZnS, and CdS) nanowires by the catalysis of nanoscale superionic-phase silver or copper(I) chalcogenides (Ag2Se, Ag2S, and Cu2S). The exceptional catalytic ability of these superionic conductors originates from their structure characteristics, known for high-density vacancies and fast mobility of silver or copper(I) cations in the rigid sublattice of Se(2-) or S(2-) ions. Insights into the SSS mechanism are provided based on the formation of solid solution and the solid-state ion diffusion/transport at solid-solid interface between catalyst and nanowire. PMID:23919513

  4. VAMAS Nb{sub 3}Sn test conductor

    SciTech Connect

    1994-01-01

    A bronze-process Nb{sub 3}Sn conductor was measured as part of the second VAMAS (Versailles Project on Advanced Materials and Standards) international critical-current round robin. The conductor specifications are given in Table 15. The critical current was measured as a function of magnetic field and axial tensile strain. The measured data are presented in Table 16 and in Figs. 23 and 24. The I{sub c} and J{sub c} values are based on an electric field criterion (E{sub c}) of 1 {mu}V/cm. In the first VAMAS round robin tests, differences in the test specimens` axial strain, caused by variations in the thermal contraction of different test fixtures, was a major source of interlaboratory variation in the critical-current data. Consequently, electromechanical characterization of the test specimen is important for data interpretation and error analysis. In the second round robin, the test apparatus and procedure were more rigidly specified. This increased experimental control reduced the critical-current variation by a factor of 3.5. The results of our measurements will be published in the final VAMAS report.

  5. Transparent Conductors from Carbon Nanotubes LBL-Assembled with Polymer Dopant with π-π Electron Transfer

    PubMed Central

    Zhu, Jian; Shim, Bong Sup; Di Prima, Matthew; Kotov, Nicholas A.

    2011-01-01

    Single-walled carbon nanotube (SWNT) and other carbon-based coatings are being considered as replacements for indium tin oxide (ITO). The problems of transparent conductors (TCs) coatings from SWNT and similar materials include poor mechanical properties, high roughness, low temperature resilience, and fast loss of conductivity. The simultaneous realization of these desirable characteristics can be achieved using high structural control of layer-by-layer (LBL) deposition, which is demonstrated by the assembly of hydroethyl cellulose (HOCS) and sulfonated polyetheretherketone (SPEEK)-SWNTs. A new type of SWNT doping based on electron transfer from valence bands of nanotubes to unoccupied levels of SPEEK through π-π interactions was identified for this system. It leads to a conductivity of 1.1×105 S/m at 66wt% loadings of SWNT. This is better than other polymer/SWNT composites and translates into surface conductivity of 920 ohms/sq and transmittance of 86.7% at 550nm. The prepared LBL films also revealed unusually high temperature resilience up to 500°C, and low roughness of 3.5 nm (ITO glass - 2.4 nm). Tensile modulus, ultimate strength, and toughness of such coatings are 13±2 GPa, 366±35 MPa and 8±3 kJ/m3, respectively, and exceed corresponding parameters of all similar TCs. The cumulative figure of merit, ΠTC, which included the critical failure strain relevant for flexible electronics, was ΠTC = 0.022 and should be compared to ΠTC = 0.006 for commercial ITO. Further optimization is possible using stratified nanoscale coatings and improved doping from the macromolecular LBL components. PMID:21524068

  6. Transparent conductors from carbon nanotubes LBL-assembled with polymer dopant with π-π electron transfer.

    PubMed

    Zhu, Jian; Shim, Bong Sup; Di Prima, Matthew; Kotov, Nicholas A

    2011-05-18

    Single-walled carbon nanotube (SWNT) and other carbon-based coatings are being considered as replacements for indium tin oxide (ITO). The problems of transparent conductors (TCs) coatings from SWNT and similar materials include poor mechanical properties, high roughness, low temperature resilience, and fast loss of conductivity. The simultaneous realization of these desirable characteristics can be achieved using high structural control of layer-by-layer (LBL) deposition, which is demonstrated by the assembly of hydroethyl cellulose (HOCS) and sulfonated polyetheretherketone (SPEEK)-SWNTs. A new type of SWNT doping based on electron transfer from valence bands of nanotubes to unoccupied levels of SPEEK through π-π interactions was identified for this system. It leads to a conductivity of 1.1 × 10(5) S/m at 66 wt % loadings of SWNT. This is better than other polymer/SWNT composites and translates into surface conductivity of 920 Ω/◻ and transmittance of 86.7% at 550 nm. The prepared LBL films also revealed unusually high temperature resilience up to 500 °C, and low roughness of 3.5 nm (ITO glass -2.4 nm). Tensile modulus, ultimate strength, and toughness of such coatings are 13 ± 2 GPa, 366 ± 35 MPa, and 8 ± 3 kJ/m(3), respectively, and exceed corresponding parameters of all similar TCs. The cumulative figure of merit, ∏(TC), which included the critical failure strain relevant for flexible electronics, was ∏(TC) = 0.022 and should be compared to ∏(TC) = 0.006 for commercial ITO. Further optimization is possible using stratified nanoscale coatings and improved doping from the macromolecular LBL components.

  7. Transparent Conductors from Carbon Nanotubes LBL-Assembled with Polymer Dopant with π-π Electron Transfer

    SciTech Connect

    Zhu, Jian; Shim, Bong Sup; Di Prima, Matthew; Kotov, Nicholas A.

    2011-01-01

    Single-walled carbon nanotube (SWNT) and other carbon-based coatings are being considered as replacements for indium tin oxide (ITO). The problems of transparent conductors (TCs) coatings from SWNT and similar materials include poor mechanical properties, high roughness, low temperature resilience, and fast loss of conductivity. The simultaneous realization of these desirable characteristics can be achieved using high structural control of layer-by-layer (LBL) deposition, which is demonstrated by the assembly of hydroethyl cellulose (HOCS) and sulfonated polyetheretherketone (SPEEK)-SWNTs. A new type of SWNT doping based on electron transfer from valence bands of nanotubes to unoccupied levels of SPEEK through π-π interactions was identified for this system. It leads to a conductivity of 1.1 × 10⁵ S/m at 66 wt % loadings of SWNT. This is better than other polymer/SWNT composites and translates into surface conductivity of 920 Ω/⟂ and transmittance of 86.7% at 550 nm. The prepared LBL films also revealed unusually high temperature resilience up to 500 °C, and low roughness of 3.5 nm (ITO glass -2.4 nm). Tensile modulus, ultimate strength, and toughness of such coatings are 13 ± 2 GPa, 366 ± 35 MPa, and 8 ± 3 kJ/m³, respectively, and exceed corresponding parameters of all similar TCs. The cumulative figure of merit, ΠTC, which included the critical failure strain relevant for flexible electronics, was ΠTC = 0.022 and should be compared to ΠTC = 0.006 for commercial ITO. Further optimization is possible using stratified nanoscale coatings and improved doping from the macromolecular LBL components.

  8. A Systematic Inventory of Motives for Becoming an Orchestra Conductor: A Preliminary Study

    ERIC Educational Resources Information Center

    Makris, Ioannis; Mullet, Etienne

    2009-01-01

    The study examined the various motives (reasons) that may have led an individual to become an orchestra conductor interpreting classical works, using Apter's (2001) Metamotivational Theory framework. Questionnaires derived from the theory, consisting of 92 possible motives for becoming an orchestra conductor, were presented to 101 orchestra…

  9. Analytical model for the dynamic resistivity of electrically-exploded conductors

    NASA Astrophysics Data System (ADS)

    Lee, R. S.

    1986-10-01

    A detailed model for the dynamic resistivity of an exploding conductor presents many difficulties, since it undergoes significant hydrodynamic expansion as it is heated. Resistivity is a function of both the temperature and density of a conductor and realistic models for resistivity over the range of parameter space experienced by an exploding conductor are quite complex. Calculation of the hydrodynamic expansion of the conductor during and subsequent to the explosion is likewise dependent on detailed knowledge of the equation of state for the conductor in a range where few experimental data exist. A further complication is the strong magnetic field which couples the hydrodynamic expansion to the currents flowing in the expanding material. In spite of the difficulties, progress is being made on detailed modeling of fuses and exploding conductors. A simpler approach has proved to be quite useful for modeling the electrical behavior of exploding bridgewire and slapper detonators and for modeling the explosions of large conductors exploded with large capacitor banks. In the work described here, a simple, empirical model was developed which can be expressed as a closed-form algebraic expression involving four parameters. This model has been used in a computer code which will calculate the burst times and burst currents for up to 15 conductors exploded in series in a capacitor-discharge circuit.

  10. The Connoisseurship of Conducting: A Qualitative Study of Exemplary Wind Band Conductors

    ERIC Educational Resources Information Center

    Barry, Nancy; Henry, Daniel

    2015-01-01

    This study aimed to gain an in-depth perspective through examining how the conducting pedagogy of three selected exemplary high school and college instrumental music conductors function within the context of an actual rehearsal. A typical rehearsal was video recorded, followed by a "think-aloud" session in which the conductor viewed the…

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

    DOEpatents

    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.

  12. Testing of flat conductor cable to Underwriters Laboratory standards UL719 and UL83

    NASA Technical Reports Server (NTRS)

    Loggins, R. W.; Herndon, R. H.

    1974-01-01

    The flat conductor cable (FCC) which was tested consisted of three AWG No. 12 flat copper conductors laminated between two films of polyethylene terephthalate (Mylar) insulation with a self-extinguishing polyester adhesive. Results of the tests conducted on this cable, according to specifications, warrants the use of this FCC for electrical interconnections in a surface nonmetallic protective covering.

  13. Effects of Conducting Plane on Band and Choral Musicians' Perceptions of Conductor and Ensemble Expressivity

    ERIC Educational Resources Information Center

    Silvey, Brian A.; Fisher, Ryan A.

    2015-01-01

    The purpose of this study was to examine whether one aspect of conducting technique, the conducting plane, would affect band and/or choral musicians' perceptions of conductor and ensemble expressivity. A band and a choral conductor were each videotaped conducting 1-min excerpts from Morten Lauridsen's "O Magnum Mysterium" while using a…

  14. Galloping of iced quad-conductors bundles based on curved beam theory

    NASA Astrophysics Data System (ADS)

    Yan, Zhitao; Savory, Eric; Li, Zhengliang; Lin, William E.

    2014-03-01

    Galloping refers to wind-induced, low-frequency, large-amplitude oscillations that have been more frequently observed for a bundle conductor than for a single conductor. In the present work two different models are built to investigate the galloping of a bundle conductor: (1) a finite curved beam element method and (2) a hybrid model based on curved beam element theory. The finite curved beam element model is effective in dealing with the spacers between the bundled conductors and the joint between the conductors and spacers that can be simulated as a rigid joint or a hinge. Furthermore, the finite curved beam element model can be used to deal with large deformation. The hybrid model invokes the small deformation hypothesis and has a high computational efficiency. A hybrid model based on conventional cable element theory is also programmed to be compared with the aforementioned models based on curved beam element theory. Numerical examples are presented to assess the accuracy of the different models in predicting the equilibrium conductor position, natural frequencies and galloping amplitude. The results show that the curved beam element models, involving more degrees of freedom and coupling of translational and torsional motion, are more accurate at simulating the static and dynamic characters of an iced quad-conductor bundle. The use of hinges, rather than rigid connections, reduces the structural response amplitudes of a galloping conductor bundle.

  15. Assignment of Appropriate Conditions for Synthesizing Tungsten Nanopowder by Electric Explosion of Conductors

    NASA Astrophysics Data System (ADS)

    Zhuravkov, S. P.; Pustovalov, A. V.; Kuznetsov, M. A.; Rosliy, I. S.; Zernin, E. A.

    2016-08-01

    The paper provides the results of experimental research into properties of tungsten nanopowders synthesized by electric explosion of a conductor in argon at various energies, put into the conductor when exploding. The authors have studied how the conditions of synthesizing the tungsten nanopowder influence on the average size of particles.

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

    SciTech Connect

    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.

  17. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems... be sized in accordance with Section 250.122 of NFPA NEC 2002 (incorporated by reference; see 46 CFR 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a...

  18. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems... be sized in accordance with Section 250.122 of NFPA NEC 2002 (incorporated by reference; see 46 CFR 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a...

  19. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems... be sized in accordance with Section 250.122 of NFPA NEC 2002 (incorporated by reference; see 46 CFR 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a...

  20. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems... be sized in accordance with Section 250.122 of NFPA NEC 2002 (incorporated by reference; see 46 CFR 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a...

  1. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems... be sized in accordance with Section 250.122 of NFPA NEC 2002 (incorporated by reference; see 46 CFR 110.10-1). (b) Each equipment-grounding conductor (other than a system-grounding conductor) of a...

  2. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Lightning arresters, ungrounded and exposed... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  3. Testing Short Samples of ITER Conductors and Projection of Their Performance in ITER Magnets

    SciTech Connect

    Martovetsky, N N

    2007-08-20

    Qualification of the ITER conductor is absolutely necessary. Testing large scale conductors is expensive and time consuming. To test straight 3-4m long samples in a bore of a split solenoid is a relatively economical way in comparison with fabrication of a coil to be tested in a bore of a background field solenoid. However, testing short sample may give ambiguous results due to different constraints in current redistribution in the cable or other end effects which are not present in the large magnet. This paper discusses processes taking place in the ITER conductor, conditions when conductor performance could be distorted and possible signal processing to deduce behavior of ITER conductors in ITER magnets from the test data.

  4. Current Sharing Temperature Test and Simulation with GANDALF Code for ITER PF2 Conductor Sample

    NASA Astrophysics Data System (ADS)

    Li, Shaolei; Wu, Yu; Liu, Bo; Weng, Peide

    2011-10-01

    Cable-in-conduit conductor (CICC) conductor sample of the PF2 coil for ITER was tested in the SULTAN facility. According to the test results, the CICC conductor sample exhibited a stable performance regarding the current sharing temperature. Under the typical operational conditions of a current of 45 kA, a magnetic field of 4 T and a temperature of 5 K for PF2, the test result for the conductor current sharing temperature is 6.71 K, with a temperature margin of 1.71 K. For a comparison thermal-hydraulic analysis of the PF2 conductor was carried out using GANDALF code in a 1-D model, and the result is consistent with the test one.

  5. Parametric analysis of hollow conductor parallel and coaxial transmission lines for high frequency space power distribution

    NASA Technical Reports Server (NTRS)

    Jeffries, K. S.; Renz, D. D.

    1984-01-01

    A parametric analysis was performed of transmission cables for transmitting electrical power at high voltage (up to 1000 V) and high frequency (10 to 30 kHz) for high power (100 kW or more) space missions. Large diameter (5 to 30 mm) hollow conductors were considered in closely spaced coaxial configurations and in parallel lines. Formulas were derived to calculate inductance and resistance for these conductors. Curves of cable conductance, mass, inductance, capacitance, resistance, power loss, and temperature were plotted for various conductor diameters, conductor thickness, and alternating current frequencies. An example 5 mm diameter coaxial cable with 0.5 mm conductor thickness was calculated to transmit 100 kW at 1000 Vac, 50 m with a power loss of 1900 W, an inductance of 1.45 micron and a capacitance of 0.07 micron-F. The computer programs written for this analysis are listed in the appendix.

  6. Development of termination and utilization concepts for flat conductor cables. Volume 3: Cost study comparison, flat versus round conductor cable

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A cost study comparing flat conductor cable (FCC) with small-gage wire (SGW) and conventional round conductor cable (RCC) is presented. This study was based on a vehicle wiring system consisting of 110,000 ft of conventional RCC equally divided between AWG sizes 20,22, and 24 using MIL-W-81044-type wire and MIL-C-26500 circular connectors. Basic cost data were developed on a similar-sized commercial jet airplane wiring system on a previous company R&D program in which advanced wiring techniques were carried through equivalent installations on an airplane mockup; and on data developed on typical average bundles during this program. Various cost elements included were engineering labor, operations (manufacturing) labor, material costs, and cost impact on payload. Engineering labor includes design, wiring system integration, wiring diagrams and cable assembly drawings, wire installations, and other related supporting functions such as the electronic data processing for the wiring. Operations labor includes mockup, tooling and production planning, fabrication, assembly, installation, and quality control cost impact on payload is the conversion of wiring system weight variations through use of different wiring concepts to program payload benefits in terms of dollars.

  7. COATING METHOD

    DOEpatents

    Townsend, R.G.

    1959-08-25

    A method is described for protectively coating beryllium metal by etching the metal in an acid bath, immersing the etched beryllium in a solution of sodium zincate for a brief period of time, immersing the beryllium in concentrated nitric acid, immersing the beryhlium in a second solution of sodium zincate, electroplating a thin layer of copper over the beryllium, and finally electroplating a layer of chromium over the copper layer.

  8. Segmented saddle-shaped passive stabilization conductors for toroidal plasmas

    DOEpatents

    Leuer, James A.

    1990-05-01

    A large toroidal vacuum chamber for plasma generation and confinement is lined with a toroidal blanket for shielding using modules segmented in the toroidal direction. To provide passive stabilization in the same manner as a conductive vacuum chamber wall, saddle-shaped conductor loops are provided on blanket modules centered on a midplane of the toroidal chamber with horizontal conductive bars above and below the midplane, and vertical conductive legs on opposite sides of each module to provide return current paths between the upper and lower horizontal conductive bars. The close proximity of the vertical legs provided on adjacent modules without making physical contact cancel the electromagnetic field of adjacent vertical legs. The conductive bars spaced equally above and below the midplane simulate toroidal conductive loops or hoops that are continuous, for vertical stabilization of the plasma even though they are actually segmented.

  9. Segmented saddle-shaped passive stabilization conductors for toroidal plasmas

    DOEpatents

    Leuer, J.A.

    1990-05-01

    A large toroidal vacuum chamber for plasma generation and confinement is lined with a toroidal blanket for shielding using modules segmented in the toroidal direction. To provide passive stabilization in the same manner as a conductive vacuum chamber wall, saddle-shaped conductor loops are provided on blanket modules centered on a midplane of the toroidal chamber with horizontal conductive bars above and below the midplane, and vertical conductive legs on opposite sides of each module to provide return current paths between the upper and lower horizontal conductive bars. The close proximity of the vertical legs provided on adjacent modules without making physical contact cancel the electromagnetic field of adjacent vertical legs. The conductive bars spaced equally above and below the midplane simulate toroidal conductive loops or hoops that are continuous, for vertical stabilization of the plasma even though they are actually segmented. 5 figs.

  10. The Image Potential for Spherical Conductors and Dielectrics

    NASA Astrophysics Data System (ADS)

    Gumbs, Godfrey; Balassis, Antonios; Iurov, Andrii; Fekete, Paula

    2013-03-01

    We calculate the image potential for spherical conductors and dielectrics, such as fullerene buckyballs. Our calculations show that these structures can support electronic states which may be localized at some distance away from the surface. These ``spherical image states'' exist within extended surface potentials formed by the competition between the attractive image force, the external electron and its image charge in the spherical shell, and the repulsive centrifugal force arising from the angular motion. The effective potential leads to extended stable states away from the surface of the spherical shell. At low temperatures, this results in long lifetimes for the image states. We expect that spherical image states with binding energies of a few meV. The bound states may be formed with the aid of radiative recombination.

  11. Preparation of transparent conductors ferroelectric memory materials and ferrites

    DOEpatents

    Bhattacharya, Raghu Nath; Ginley, David S.

    1998-01-01

    A process for the preparation by electrodeposition of metal oxide film and powder compounds for ferroelectric memory materials and ferrites wherein the metal oxide includes a plurality of metals. The process comprises providing an electrodeposition bath, providing soluble salts of the metals to this bath, electrically energizing the bath to thereby cause formation of a recoverable film of metal on the electrode, recovering the resultant film as a film or a powder, and recovering powder formed on the floor of the bath. The films and powders so produced are subsequently annealed to thereby produce metal oxide for use in electronic applications. The process can be employed to produce metal-doped metal oxide film and powder compounds for transparent conductors. The process for preparation of these metal-doped metal oxides follows that described above.

  12. Preparation of transparent conductors ferroelectric memory materials and ferrites

    DOEpatents

    Bhattacharya, R.N.; Ginley, D.S.

    1998-07-28

    A process is described for the preparation by electrodeposition of metal oxide film and powder compounds for ferroelectric memory materials and ferrites wherein the metal oxide includes a plurality of metals. The process comprises providing an electrodeposition bath, providing soluble salts of the metals to this bath, electrically energizing the bath to thereby cause formation of a recoverable film of metal on the electrode, recovering the resultant film as a film or a powder, and recovering powder formed on the floor of the bath. The films and powders so produced are subsequently annealed to thereby produce metal oxide for use in electronic applications. The process can be employed to produce metal-doped metal oxide film and powder compounds for transparent conductors. The process for preparation of these metal-doped metal oxides follows that described above.

  13. Polysulfide flow batteries enabled by percolating nanoscale conductor networks.

    PubMed

    Fan, Frank Y; Woodford, William H; Li, Zheng; Baram, Nir; Smith, Kyle C; Helal, Ahmed; McKinley, Gareth H; Carter, W Craig; Chiang, Yet-Ming

    2014-01-01

    A new approach to flow battery design is demonstrated wherein diffusion-limited aggregation of nanoscale conductor particles at ∼1 vol % concentration is used to impart mixed electronic-ionic conductivity to redox solutions, forming flow electrodes with embedded current collector networks that self-heal after shear. Lithium polysulfide flow cathodes of this architecture exhibit electrochemical activity that is distributed throughout the volume of flow electrodes rather than being confined to surfaces of stationary current collectors. The nanoscale network architecture enables cycling of polysulfide solutions deep into precipitation regimes that historically have shown poor capacity utilization and reversibility and may thereby enable new flow battery designs of higher energy density and lower system cost. Lithium polysulfide half-flow cells operating in both continuous and intermittent flow mode are demonstrated for the first time. PMID:24597525

  14. Non-classical radiation emission by a coherent conductor

    NASA Astrophysics Data System (ADS)

    Forgues, Jean-Charles; Gasse, Gabriel; Lupien, Christian; Reulet, Bertrand

    2016-08-01

    We report experimental evidence that the microwave electromagnetic field generated by a normal conductor, here a tunnel junction placed at ultra-low temperature, can be non-classical. By measuring the quadratures of the electromagnetic field at one or two frequencies in the GHz range, we demonstrate the existence of squeezing as well as entanglement in such radiation. In one experiment, we observe that the variance of one quadrature of the photo-assisted noise generated by the junction goes below its vacuum level. In the second experiment, we demonstrate the existence of correlations between the quadratures taken at two frequencies, which can be stronger than allowed by classical mechanics, proving that the radiation at those two frequencies are entangled.

  15. Topological phase transition in quasi-one dimensional organic conductors.

    PubMed

    Ye, Xiao-Shan; Liu, Yong-Jun; Zeng, Xiang-Hua; Wu, Guoqing

    2015-01-01

    We explore topological phase transition, which involves the energy spectra of field-induced spin-density-wave (FISDW) states in quasi-one dimensional (Q1D) organic conductors, using an extended Su-Schrieffer-Heeger (SSH) model. We show that, in presence of half magnetic-flux FISDW state, the system exhibits topologically nontrivial phases, which can be characterized by a nonzero Chern number. The nontrivial evolution of the bulk bands with chemical potential in a topological phase transition is discussed. We show that the system can have a similar phase diagram which is discussed in the Haldane's model. We suggest that the topological feature should be tested experimentally in this organic system. These studies enrich the theoretical research on topologically nontrivial phases in the Q1D lattice system as compared to the Haldane topological phase appearing in the two-dimensional lattices. PMID:26612317

  16. Combined Jonker and Ioffe Analysis of Oxide Conductors and Semiconductors

    SciTech Connect

    Zhu, Q.M.; Hopper, E.M.; Ingram, B.J.; Mason, Thomas O.

    2010-09-27

    Jonker plots (Seebeck coefficient versus logarithm of conductivity) have been utilized to obtain the product of the density of states (DOS) and mobility (μ) in oxide semiconductors, from which the maximum electrical conductivity can be estimated for degenerate transparent conducting oxide (TCO) applications. In addition, the DOS–μ product can be utilized to predict the maximum achievable “power factor” (PF, Seebeck coefficient squared times conductivity) for oxide semiconductors. The PF is an important parameter governing the figure of merit for thermoelectric oxide (TEO) applications. The procedure employs an analysis developed by Ioffe, and provides an important screening tool for oxide (and other) thermoelectric materials, based upon data from polycrystalline ceramic specimens. Several oxides, including known transparent conductors, are considered as TCO and TEO case studies in the present work.

  17. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    SciTech Connect

    Hernández, C.; Consejo, C.; Chaubet, C.; Degiovanni, P.

    2014-03-28

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100 Hz, 1 MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Büttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor.

  18. Topological phase transition in quasi-one dimensional organic conductors

    NASA Astrophysics Data System (ADS)

    Ye, Xiao-Shan; Liu, Yong-Jun; Zeng, Xiang-Hua; Wu, Guoqing

    2015-11-01

    We explore topological phase transition, which involves the energy spectra of field-induced spin-density-wave (FISDW) states in quasi-one dimensional (Q1D) organic conductors, using an extended Su-Schrieffer-Heeger (SSH) model. We show that, in presence of half magnetic-flux FISDW state, the system exhibits topologically nontrivial phases, which can be characterized by a nonzero Chern number. The nontrivial evolution of the bulk bands with chemical potential in a topological phase transition is discussed. We show that the system can have a similar phase diagram which is discussed in the Haldane’s model. We suggest that the topological feature should be tested experimentally in this organic system. These studies enrich the theoretical research on topologically nontrivial phases in the Q1D lattice system as compared to the Haldane topological phase appearing in the two-dimensional lattices.

  19. Topological phase transition in quasi-one dimensional organic conductors

    PubMed Central

    Ye, Xiao-Shan; Liu, Yong-Jun; Zeng, Xiang-Hua; Wu, Guoqing

    2015-01-01

    We explore topological phase transition, which involves the energy spectra of field-induced spin-density-wave (FISDW) states in quasi-one dimensional (Q1D) organic conductors, using an extended Su-Schrieffer-Heeger (SSH) model. We show that, in presence of half magnetic-flux FISDW state, the system exhibits topologically nontrivial phases, which can be characterized by a nonzero Chern number. The nontrivial evolution of the bulk bands with chemical potential in a topological phase transition is discussed. We show that the system can have a similar phase diagram which is discussed in the Haldane’s model. We suggest that the topological feature should be tested experimentally in this organic system. These studies enrich the theoretical research on topologically nontrivial phases in the Q1D lattice system as compared to the Haldane topological phase appearing in the two-dimensional lattices. PMID:26612317

  20. Entanglement entropy in dynamic quantum-coherent conductors

    NASA Astrophysics Data System (ADS)

    Thomas, Konrad H.; Flindt, Christian

    2015-03-01

    We investigate the entanglement and the Rényi entropies of two electronic leads connected by a quantum point contact. For noninteracting electrons, the entropies can be related to the cumulants of the full counting statistics of transferred charge which in principle are measurable. We consider the entanglement entropy generated by operating the quantum point contact as a quantum switch which is opened and closed in a periodic manner. Using a numerically exact approach we analyze the conditions under which a logarithmic growth of the entanglement entropy predicted by conformal field theory should be observable in an electronic conductor. In addition, we consider clean single-particle excitations on top of the Fermi sea (levitons) generated by applying designed pulses to the leads. We identify a Hong-Ou-Mandel-like suppression of the entanglement entropy by interfering two levitons on a quantum point contact tuned to half transmission.