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1

HTS Wire Development Workshop: Proceedings  

SciTech Connect

The 1994 High-Temperature Superconducting Wire Development Workshop was held on February 16--17 at the St. Petersburg Hilton and Towers in St. Petersburg, Florida. The meeting was hosted by Florida Power Corporation and sponsored by the US Department of Energy`s Superconductivity Program for Electric Power Systems. The meeting focused on recent high-temperature superconducting wire development activities in the Department of Energy`s Superconductivity Systems program. The meeting opened with a general discussion on the needs and benefits of superconductivity from a utility perspective, the US global competitiveness position, and an outlook on the overall prospects of wire development. The meeting then focused on four important technology areas: Wire characterization: issues and needs; technology for overcoming barriers: weak links and flux pinning; manufacturing issues for long wire lengths; and physical properties of HTS coils. Following in-depth presentations, working groups were formed in each technology area to discuss the most important current research and development issues. The working groups identified research areas that have the potential for greatly enhancing the wire development effort. These areas are discussed in the summary reports from each of the working groups. This document is a compilation of the workshop proceedings including all general session presentations and summary reports from the working groups.

Not Available

1994-07-01

2

Synchronous motor with HTS-2G wires  

NASA Astrophysics Data System (ADS)

One of the applications of new high-temperature superconductor materials (HTS) is field coils for synchronous electrical machines. The use of YBCO 2G HTS tapes (HTS-2G) allows increasing of magnetic flux density in the air gap, which will increase the output power and reduce the dimensions of the motor. Such motors with improved characteristics can be successfully used in transportation as traction motor. In MAI-based "Center of Superconducting machines and devices" with the support of "Rosatom" has been designed and tested a prototype of the 50 kW synchronous motor with radial magnetic flux from a field-coils based on HTS-2G tapes. The experimental and theoretical results are presented.

Dezhin, D.; Ilyasov, R.; Kozub, S.; Kovalev, K.; Verzhbitsky, L.

2014-05-01

3

Design and manufacture of a D-shape coil-based toroid-type HTS DC reactor using 2nd generation HTS wire  

NASA Astrophysics Data System (ADS)

This paper describes the design specifications and performance of a real toroid-type high temperature superconducting (HTS) DC reactor. The HTS DC reactor was designed using 2G HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The target inductance of the HTS DC reactor was 400 mH. The expected operating temperature was under 20 K. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. Performances of the toroid-type HTS DC reactor were analyzed through experiments conducted under the steady-state and charge conditions. The fundamental design specifications and the data obtained from this research will be applied to the design of a commercial-type HTS DC reactor.

Kim, Kwangmin; Go, Byeong-Soo; Sung, Hae-Jin; Park, Hea-chul; Kim, Seokho; Lee, Sangjin; Jin, Yoon-Su; Oh, Yunsang; Park, Minwon; Yu, In-Keun

2014-09-01

4

Study of HTS Wires at High Magnetic Fields  

SciTech Connect

Fermilab is working on the development of high field magnet systems for ionization cooling of muon beams. The use of high temperature superconducting (HTS) materials is being considered for these magnets using Helium refrigeration. Critical current (I{sub c}) measurements of HTS conductors were performed at FNAL and at NIMS up to 28 T under magnetic fields at zero to 90 degree with respect to the sample face. A description of the test setups and results on a BSCCO-2223 tape and second generation (2G) coated conductors are presented.

Turrioni, D.; Barzi, E.; Lamm, M.J.; Yamada, R.; Zlobin, A.V.; Kikuchi, A.; /Fermilab

2009-01-01

5

Applied Hts Bulks and Wires to Rotating Machines for Marine Propulsion  

NASA Astrophysics Data System (ADS)

High-temperature superconductors allow a compact and efficient way to provide high-torque density to rotating machines with excellent operation. A field pole, providing flux density of more than 1.5 T around the armature, was initially designed for an axial-gap type with the flux parallel to the rotor axis. Melt-growth Gd-123 bulks as well as Bi-2223 wire windings have been successfully assembled on the rotor disk. No iron core was used, though being an auxiliary flux control found in most HTS motors. Both bulk and wire types have realized a practical motor operation within a limited output range. For bulks, a 15 kW, 720 rpm, synchronous motor was designed and tested in the group of TUMSAT, Kitano Seiki and University of Fukui. A bulk field pole was cooled down by liquid nitrogen and was magnetized in the motor. To enhance the output power to more than 30 kW, we developed a thermosyphon system using condensed neon. Another field pole with HTS wire for large-scale marine propulsion is also discussed on a 100 kW, 230 rpm tested machine. A closed-cycle condensed neon associated with thermal insulation is also reported.

Miki, M.; Felder, B.; Kimura, Y.; Tsuzuki, K.; Taguchi, R.; Shiliang, Y.; Xu, Y.; Ida, T.; Izumi, M.

2010-04-01

6

Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets  

SciTech Connect

The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between the project start and that date a substantial shift in the MRI marketplace occurred, with rapid growth for systems at higher fields (1.5 T and above) and a consequent decline in the low field market (<1.0 T). While the project aim appeared technically attainable at that time, the conclusion was reached that the system and market economics do not warrant additional investment. The program was redirected to develop BSCCO 2212 multifilament wire development for high field superconducting magnets for NMR and other scientific research upon an agreement between DOE and Oxford Instruments, Superconducting Technology. The work t took place between September, 2004 and the project end in early 2006 was focused on 2212 multifilamentary wire. This report summarizes the technical achievements both in 2212 dip coated for an HTS MRI system and in BSCCO 2212 multifilamentary wire for high field magnets.

Kennth Marken

2006-08-11

7

Quench initiation and propagation characteristics of HTS wires under liquid nitrogen cooling condition  

Microsoft Academic Search

With the successful commercialization of Bi-2223 powder-in-tube tape and the improving quality & length-scale of YBCO coated tape, HTS magnets for high magnetic field and electric power applications have been developed. Although the operating temperature of HTS magnets must be kept in the designed level, the magnetic energy and mechanical disturbances can cause a thermal run-away. Especially, heat energy generated

Duck Kweon Bae; Dong Keun Park; Min Cheol Ahn; Hyoungku Kang; Yong Soo Yoon; Tae Kuk Ko

2006-01-01

8

V-1 TRANSITION AND N-VALUE OF MULTIFILAMENTARY LTS AND HTS WIRES AND CABLES.  

SciTech Connect

For low T, multifilamentary conductors like NbTi and Nb{sub 3}Sn, the V-I transition to the normal state is typically quantified by the parameter, n, defined by ({rho}/{rho}{sub c})= (I/I{sub c}){sup n}. For NbTi, this parameterization has been very useful in the development of high Jc wires, where the n-value is regarded as an index of the filament quality. In copper-matrix wires with undistorted filaments, the n-value at 5T is {approx} 40-60, and drops monotonically with increasing field. However, n can vary significantly in conductors with higher resistivity matrices and those with a low copper fraction. Usually high n-values are associated with unstable resistive behavior and premature quenching. The n-value in NbTi Rutherford cables, when compared to that in the wires is useful in evaluating cabling degradation of the critical current due to compaction at the edges of the cable. In Nb{sub 3}Sn wires, n-value has been a less useful tool, since often the resistive transition shows small voltages {approx} a few {mu}V prior to quenching. However, in ''well behaved'' wires, n is {approx} 30-40 at 12T and also shows a monotonic behavior with field. Strain induced I{sub c} degradation in these wires is usually associated with lower n-values. For high T{sub c} multifilamentary wires and tapes, a similar power law often describes the resistive transition. At 4.2K, Bi-2223 tapes as well as Bi-2212 wires exhibit n-values {approx} 15-20. In either case, n does not change appreciably with field. Rutherford cables of Bi-2212 wire show lower values of n than the virgin wire.

GHOSH,A.K.

2003-05-25

9

Reflective HTS switch  

DOEpatents

A HTS (High Temperature Superconductor) switch includes a HTS conductor for providing a superconducting path for an electrical signal and an serpentine wire actuator for controllably heating a portion of the conductor sufficiently to cause that portion to have normal, and not superconducting, resistivity. Mass of the portion is reduced to decrease switching time. 6 figs.

Martens, J.S.; Hietala, V.M.; Hohenwarter, G.K.G.

1994-09-27

10

Reflective HTS switch  

SciTech Connect

A HTS switch includes a HTS conductor for providing a superconducting path for an electrical signal and an serpentine wire actuator for controllably heating a portion of the conductor sufficiently to cause that portion to have normal, and not superconducting, resistivity. Mass of the portion is reduced to decrease switching time.

Martens, Jon S. (Albuquerque, NM); Hietala, Vincent M. (Placitas, NM); Hohenwarter, Gert K. G. (Madison, WI)

1994-01-01

11

Contribution of ion beam analysis methods to the development of 2nd generation high temperature superconducting (HTS) wires  

SciTech Connect

One of the crucial steps in the second generation high temperature superconducting wire program was development of the buffer layer architecture. The architecture designed at the Superconductivity Technology Center at Los Alamos National Laboratory consists of several oxide layers wherein each layer plays a specific role, namely: nucleation layer, diffusion barrier, biaxially textured template, and an intermediate layer with a good match to the lattice parameter of superconducting Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} (YBCO) compound. This report demonstrates how a wide range of ion beam analysis techniques (SIMS, RBS, channeling, PIXE, PIGE, NRA, ERD) was employed for analysis of each buffer layer and the YBCO films. These results assisted in understanding of a variety of physical processes occurring during the buffet layer fabrication and helped to optimize the buffer layer architecture as a whole.

Usov, Igor O [Los Alamos National Laboratory; Arendt, Paul N [Los Alamos National Laboratory; Stan, Liliana [Los Alamos National Laboratory; Holesinger, Terry G [Los Alamos National Laboratory; Foltyn, Steven R [Los Alamos National Laboratory; Depaula, Raymond F [Los Alamos National Laboratory

2009-01-01

12

Commercialization of Medium Voltage HTS Triax TM Cable Systems  

SciTech Connect

The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

Knoll, David

2012-12-31

13

DEVELOPMENT OF HTS CONDUCTORS FOR ELECTRIC POWER APPLICATIONS  

SciTech Connect

Second generation (2G) technologies to fabricate high-performance superconducting wires developed at the Oak Ridge National Laboratory (ORNL) were transferred to American Superconductor via this CRADA. In addition, co-development of technologies for over a decade was done to enable fabrication of commercial high-temperature superconducting (HTS) wires with high performance. The massive success of this CRADA has allowed American Superconductor Corporation (AMSC) to become a global leader in the fabrication of HTS wire and the technology is fully based on the Rolling Assisted Biaxially Textured Substrates (RABiTS) technology invented and developed at ORNL.

Goyal, A.; Rupich, M. (American Superconductor Corp.)

2012-10-23

14

Optimized HTS current leads  

Microsoft Academic Search

The problem of optimizing HTS current leads by varying their cross-section along the length is investigated both experimentally and numerically at 500 A current level. Bi-2223-based HTS multi-filament composite tapes were used with two types of matrices: pure Ag and (Ag+1 at.% Au) alloy. The warm ends of the HTS parts of the current leads were cooled with liquid nitrogen.

Andrew V. Gavrilin; Victor E. Keilin; Ivan A. Kovalev; Sergei L. Kruglov; Vladimir I. Shcherbakov; Igor I. Akimov; Dmitry K. Rakov; Alexander K. Shikov

1999-01-01

15

Development of HTS power cable using YBCO coated conductor  

NASA Astrophysics Data System (ADS)

Reductions of AC losses and of cost of HTS power cables are important to put it into practical power networks. Since an YBCO-coated-conductor (YBCO tape) has higher Jc and better magnetic property than a Bi2223-Ag-sheathed-tape, an AC power cable using YBCO tapes will obtain higher performance than XLPE-cables and HTS cables using BSCCO tapes in future. Especially, an YBCO HTS cable will be expected to become a higher economical cable than a Bi cable because an YBCO tape reduced its AC losses and its wire cost. We have started developing HTS power cables using YBCO tapes. Mechanical properties, superconducting properties and other electro magnetic properties of YBCO tapes have been measured to estimate the applicability to the HTS cable. Moreover, we have developed some technologies to bring out latent potentials of YBCO tapes.

Mukoyama, Shinichi; Yagi, Masashi; Hirano, Hironobu; Yamada, Yutaka; Izumi, Teruo; Shiohara, Yuh

2006-10-01

16

Test Results for a 25 Meter Prototype Fault Current Limiting Hts Cable for Project Hydra  

NASA Astrophysics Data System (ADS)

The Oak Ridge National Laboratory (ORNL) has tested a 25-m long prototype High Temperature Superconducting (HTS) cable with inherent Fault-Current Limiting (FCL) capability at its HTS cable test facility. The HTS-FCL cable and terminations were designed and fabricated by Ultera, which is a joint venture between Southwire and nkt cables. System integration and HTS wire were provided by American Superconductor Corporation who was the overall team leader of the project. The ultimate goal of the 25-m HTS-FCL cable test program was to verify the design and ensure the operational integrity for the eventual installation of a ˜200-m fully functional HTS-FCL cable in the Consolidated Edison electric grid located in downtown New York City. The 25-m HTS-FCL cable consisted of a three-phase (3-?) HTS Triax™ design with a cold dielectric between the phases. The HTS-FCL cable had an operational voltage of 13.8 kV phase-to-phase (7967 V phase-to-ground) and an operating current of 4000 Arms per phase, which is the highest operating current to date of any HTS cable. The 25-m HTS-FCL cable was subjected to a series of cryogenic and electrical tests. Test results from the 25-m HTS-FCL cable are presented and discussed.

Rey, C. M.; Duckworth, R. C.; Demko, J. A.; Ellis, A.; James, D. R.; Gouge, M. J.; Tuncer, E.

2010-04-01

17

Sub-Cooled Liquid Nitrogen Test System for Cooling HTS Synchronous Motor  

Microsoft Academic Search

A 400 kW radial-axial flux type experimental HTS synchronous motor is designed. There are twelve armature coils using HTS wires in the motor. They are accommodated in the cooling vessels made of FRP material, and twelve cooling vessels are enclosed in the vacuum vessel. In order to cool the HTS coils of the motor, a sub-cooled liquid nitrogen cryogenic system

Anbin Chen; Fengyu Xu; Xiaokun Liu; Yubao He; Zonglin Wu; Yingshun Zhu; Zhengnan Han; Liyi Li

2012-01-01

18

Review of activities in USA on HTS materials  

SciTech Connect

Rapid progress in attaining practical applications of High Temperature Superconductors (HTS) has been made since the discovery of these new materials. Many critical parameters influencing HTS powder synthesis and wire processing have been identified through a combination of fundamental exploration and applied research. The complexity of these novel materials with regard to phase behavior and physical properties has become evident as a result of these careful studies. Achieving optimal mechanical and superconducting properties in wires and tapes will require further understanding and synergy among several different technical disciplines. Highlights of efforts towards producing practical superconductors for electric power applications based on rare earth-, bismuth-, and thallium-based systems are reviewed.

Peterson, D.E.

1995-02-01

19

HTS thin films: Passive microwave components and systems integration issues  

SciTech Connect

The excellent microwave properties of the High-Temperature-Superconductors (HTS) have been amply demonstrated in the laboratory by techniques such as resonant cavity, power transmission and microstrip resonator measurements. The low loss and high Q passive structures made possible with HTS, present attractive options for applications in commercial, military and space-based systems. However, to readily insert HTS into these systems improvement is needed in such areas as repeatability in the deposition and processing of the HTS films, metal-contact formation, wire bonding, and overall film endurance to fabrication and assembly procedures. In this paper we present data compiled in our lab which illustrate many of the problems associated with these issues. Much of this data were obtained in the production of a space qualified hybrid receiver-downconverter module for the Naval Research Laboratory`s High Temperature Superconductivity Space Experiment II (HTSSE-II). Examples of variations observed in starting films and finished circuits will be presented. It is shown that under identical processing the properties of the HTS films can degrade to varying extents. Finally, we present data on ohmic contacts and factors affecting their adhesion to HTS films, strength of wire bonds made to such contacts, and aging effects.

Miranda, F.A.; Chorey, C.M.; Bhasin, K.B. [National Aeronautics and Space Administration, Cleveland, OH (United States)

1994-12-31

20

HTS thin films: Passive microwave components and systems integration issues  

NASA Technical Reports Server (NTRS)

The excellent microwave properties of the High-Temperature-Superconductors (HTS) have been amply demonstrated in the laboratory by techniques such as resonant cavity, power transmission and microstrip resonator measurements. The low loss and high Q passive structures made possible with HTS, present attractive options for applications in commercial, military and spacebased systems. However, to readily insert HTS into these systems improvement is needed in such areas as repeatability in the deposition and processing of the HTS films, metal-contact formation, wire bonding, and overall film endurance to fabrication and assembly procedures. In this paper we present data compiled in our lab which illustrate many of the problems associated with these issues. Much of this data were obtained in the production of a space qualified hybrid receiver-downconverter module for the Naval Research Laboratory's High Temperature Superconductivity Space Experiment 2 (HTSSE-2). Examples of variations observed in starting films and finished circuits will be presented. It is shown that under identical processing the properties of the HTS films can degrade to varying extents. Finally, we present data on ohmic contacts and factors affecting their adhesion to HTS films, strength of wire bonds made to such contacts, and aging effects.

Miranda, F. A.; Chorey, C. M.; Bhasin, K. B.

1995-01-01

21

HTS Thin Films: Passive Microwave Components and Systems Integration Issues  

NASA Technical Reports Server (NTRS)

The excellent microwave properties of the High-Temperature-Superconductors (HTS) have been amply demonstrated in the laboratory by techniques such as resonant cavity, power transmission and microstrip resonator measurements. The low loss and high Q passive structures made possible with HTS, present attractive options for applications in commercial, military and space-based systems. However, to readily insert HTS into these systems, improvement is needed in such areas as repeatability in the deposition and processing of the HTS films, metal-contact formation, wire bonding, and overall film endurance to fabrication and assembly procedures. In this paper, we present data compiled in our lab which illustrate many of the problems associated with these issues. Much of this data were obtained in the production of a space qualified hybrid receiver-downconverter module for the Naval Research Laboratory's High Temperature Superconductivity Space Experiment II (HTSSE-II). Examples of variations observed in starting films and finished circuits will be presented. It is shown that under identical processing the properties of the HTS films can degrade to varying extents. Finally, we present data on ohmic contacts and factors affecting their adhesion to HTS films, strength of wire bonds made to such contacts, and aging effects.

Miranda, F. A.; Chorey, C. M.; Bhasin, K. B.

1995-01-01

22

SUPERCONDUCTIVITY PROGRAM RESEARCH AND DEVELOPMENT High Temperature Superconductivity (HTS) is a technology with the potential  

E-print Network

#12;SUPERCONDUCTIVITY PROGRAM RESEARCH AND DEVELOPMENT High Temperature Superconductivity (HTS-of-way. The Department of Energy's efforts to advance High Temperature Superconductivity combine major national strengths: the Superconductivity Partnership Initiative (SPI), the 2nd Generation Wire Initiative

23

Superconducting Wires Enabled by Nanodots wins Nano50TM Award  

E-print Network

includes nanoscale columns of non-superconducting material embedded within the superconductorSuperconducting Wires Enabled by Nanodots wins Nano50TM Award HTS Wires Enabled via 3D Self-Assembly of Insulating Nanodots Background · For most large-scale applications of high-temperature superconducting (HTS

24

Influence of Proton Irradiation on Angular Dependence of Second Generation (2G)HTS  

SciTech Connect

In the Facility for Rare Isotope Beams (FRIB) the quadrupoles in the fragment separator are exposed to very high radiation and heat loads. High Temperature Superconductors (HTS) are a good candidate for these magnets because they can be used at {approx}30-50 K and tolerate higher heat generation than Nb-Ti magnets. Radiation damage studies of HTS wires are crucial to ensure that they will survive in a high radiation environment. HTS wires from two vendors were studied. Samples of 2G HTS wires from SuperPower and American Superconductor (ASC) were irradiated with a 42 {mu}A, 142 MeV proton beam from the Brookhaven Linac Isotope Producer (BLIP). The angular dependence of the critical current was measured in magnetic fields at 77K.

Shiroyanagi, Y.; Greene, G.; Gupta, R.; Sampson, W.

2011-05-01

25

HTS cable design and evaluation in YOKOHAMA Project  

NASA Astrophysics Data System (ADS)

HTS cable demonstration project supported by Ministry of Economy, Trade and Industry (METI) and New Energy and Industrial Technology Development Organization (NEDO) has started since FY 2007 in Japan. The target of this project is to operate a 66 kV, 200 MVA HTS cable in the live network of Tokyo Electric Power Company (TEPCO) in order to demonstrate its reliability and stable operation. Various preliminary tests with the short core samples were conducted to confirm the HTS cable design. One of the technical targets in this project is to reduce the AC losses of HTS cable cores. For this purpose, a new type DI-BSCCO wire with twisted superconducting filaments which is named TypeAC is applied in the cable core. A short cable core made with TypeAC wires shows its AC loss is 0.8 W/m/ph at 2 kArms, which is about 1/4 of the one with standard DI-BSCCO wires. Another important target is to manage a fault current. At a preliminary test with the short cable cores, it showed that the cable could manage the through-fault of 10 kA at 2 sec and survived at 31.5 kA at 2 sec. As the electric insulation tests, AC 90 kV for 3 hours and lightning impulse at ±385kV, 3 shots for each were applied to a cable core, successfully. The results of tensile and bending tests showed the cable core has good mechanical properties. The design of the HTS cable for YOKOHAMA project has been completed as well as those of a termination and a joint. A 30-meter HTS cable was manufactured and a 30-meter HTS cable system was installed in SEI facility. The cable system was cooled down and tested to verify its performance before constructing the HTS cable system in YOKOHAMA. This paper describes the design and test results of the 30-meter HTS cable, and also performance test results of the 30-meter cable system.

Yumura, H.; Ohya, M.; Ashibe, Y.; Watanabe, M.; Minamino, T.; Masuda, T.; Honjo, S.; Mimura, T.; Kitoh, Y.; Noguchi, Y.

2010-06-01

26

Current Estimation of an HTS BSCCO Magnet Having Multiple Power Sources Based on the Field Dependent Relation  

Microsoft Academic Search

Due to the anisotropy of a tape-shaped HTS wire, the method to determine the operating current of an HTS magnet needs to be different from that of a LTS magnet. This paper presented estimation of the critical current of pancake windings excited by multiple power sources. Critical currents were determined by using field dependent E-J relation. A new method to

Myunghun Kang; Myunghwan Koo; Heejoon Lee; Gueesoo Cha

2009-01-01

27

Design and Development of a 100 MVA HTS Generator for Commercial Entry  

SciTech Connect

In 2002, General Electric and the US Department of Energy (DOE) entered into a cooperative agreement for the development of a commercialized 100 MVA generator using high temperature superconductors (HTS) in the field winding. The intent of the program was to: (1) identify and develop technologies that would be needed for such a generator; (2) develop conceptual designs for generators with ratings of 100 MVA and higher using HTS technology; (3) perform proof of concept tests at the 1.5 MW level for GE's proprietary warm iron rotor HTS generator concept; and (4) design, build, and test a prototype of a commercially viable 100 MVA generator that could be placed on the power grid. This report summarizes work performed during the program and is provided as one of the final program deliverables. The design for the HTS generator was based on GE's warm iron rotor concept in which a cold HTS coil is wound around a warm magnetic iron pole. This approach for rotating HTS electrical machinery provides the efficiency benefits of the HTS technology while addressing the two most important considerations for power generators in utility applications: cost and reliability. The warm iron rotor concept uses the least amount of expensive HTS wire compared to competing concepts and builds on the very high reliability of conventional iron core stators and armature windings.

None

2007-06-07

28

Thermal management of long-length HTS cable systems  

SciTech Connect

Projections of electric power production suggest a major shift to renewables, such as wind and solar, which will be in remote locations where massive quantities of power are available. One solution for transmitting this power over long distances to load centers is direct current (dc), high temperature superconducting (HTS) cables. Electric transmission via dc cables promises to be effective because of the low-loss, highcurrent- carrying capability of HTS wire at cryogenic temperatures. However, the thermal management system for the cable must be carefully designed to achieve reliable and energyefficient operation. Here we extend the analysis of a superconducting dc cable concept proposed by the Electric Power Research Institute (EPRI), which has one stream of liquid nitrogen flowing in a cryogenic enclosure that includes the power cable, and a separate return tube for the nitrogen. Refrigeration stations positioned every 10 to 20 km cool both nitrogen streams. Both go and return lines are contained in a single vacuum/cryogenic envelope. Other coolants, including gaseous helium and gaseous hydrogen, could provide potential advantages, though they bring some technical challenges to the operation of long-length HTS dc cable systems. A discussion of the heat produced in superconducting cables and a system to remove the heat are discussed. Also, an analysis of the use of various cryogenic fluids in long-distance HTS power cables is presented.

Demko, Jonathan A [ORNL; Hassenzahl, William V [ORNL

2011-01-01

29

HTS magnetometers for fetal magnetocardiography.  

PubMed

High temperature superconducting (HTS) SQUID sensors have adequate magnetic field sensitivity for adult magnetocardiography (MCG) measurements, but it remains to be seen how well they perform for fetal MCG (fMCG), where the heart signals are typically ten times smaller than the adult signals. In this study, we assess the performance of a prototype HTS SQUID system; namely, a three-SQUID gradiometer formed from three vertically-aligned HTS dc-SQUID magnetometers integrated into a fiberglass liquid nitrogen dewar of diameter 12.5 cm and height 30 cm. Axial gradiometers with short or long baseline, as well as a second order gradiometer, can be formed out of these magnetometers via electronic subtraction. The calibrated magnetometer sensitivities at 1 kHz are 109 fT/square root of Hz, 155 fT/square root of Hz and 51 fT/square root of Hz. Direct comparison is made between the HTS SQUID system and a LTS SQUID system by making recordings with both systems during the same session on adult and fetal subjects. Although the fMCG could be resolved with the HTS SQUID system in most near-term subjects, the signal-to-noise ratio was relatively low and the system could not be operated outside of a shielded room. PMID:16012655

Li, Z; Wakai, R T; Paulson, D N; Schwartz, B

2004-01-01

30

Development Status of AMSC Amperium® Wire  

NASA Astrophysics Data System (ADS)

AMSC produces Second Generation (2G) HTS wire for utility power applications as well as coil, motor and generator solutions. In this paper, various types of AMSC's Amperium® wire suitable to power cables, fault current limiters and coils are reviewed. In addition, recently developed performance-improvements in amperage, reduced ac power loss and mechanical properties are summarized. The introduction of thicker HTS layers coupled with optimized heat treatments to enhance critical current density dramatically improve both cable and coil wire current-carrying capability. A non-magnetic RABiTSTM substrate has now been developed to the point where it is compatible with the manufacturing process and capable of sustaining large critical currents. Finally, the ability of Amperium® wires to withstand cable-winding stresses, and to exhibit the high transverse c-axis strength critical to the reliability of the wire in coils, are discussed.

Fleshler, S.; DeMoranville, K.; Gannon, J., Jr.; Li, X.; Podtburg, E.; Rupich, M. W.; Sathyamurthy, S.; Thieme, C. L. H.; Tucker, D.; Whitman, L.

2014-05-01

31

Race-track coils for a 3 MW HTS ship motor  

NASA Astrophysics Data System (ADS)

Since the discovery of high-temperature superconductivity (HTS), Sumitomo Electric has been developing silver-sheathed Bi2223 superconducting wire and products. Ship propulsion motors are one of the most promising applications of HTS. Sumitomo Electric Industries, Ltd. (SEI) has recently manufactured 24 large racetrack coils, using 70 km long DI-BSCCO wires, for use in a 3 MW HTS motor developed by Kawasaki Heavy Industries, Ltd. (KHI). The 3 MW HTS motor, using our newly developed racetrack coils, has successfully passed the loading test. It is particularly important that the HTS field coils used in ship propulsion motors can withstand the expansive forces repeatedly applied to them. As racetrack type coils have straight sections, the support mechanism they require to withstand expansive forces is very different from that of circular coils. Therefore, we ran tests and obtained the basic data to evaluate the 20-year durability of racetrack coils against the repeatedly applied expansive forces expected in domestic ship propulsion motors.

Ueno, E.; Kato, T.; Hayashi, K.

2014-09-01

32

Hysteresis and reluctance electric machines with bulk HTS rotor elements  

Microsoft Academic Search

Two new types of HTS electric machines are considered. The first type is hysteresis motors and generators with cylindrical and disk rotors containing bulk HTS elements. The second type is reluctance motors with compound HTS-ferromagnetic rotors. The compound HTS-ferromagnetic rotors, consisting of joined alternating bulk HTS (YBCO) and ferromagnetic (iron) plates, provide a new active material for electromechanical purposes. Such

L. K. Kovalev; K. V. Ilushin; S. M.-A. Koneev; K. L. Kovalev; V. T. Penkin; V. N. Poltavets; W. Gawalek; T. Habisreuther; B. Oswald; K.-J. Best

1999-01-01

33

Study on stabilization and quench protection of coils wound of HTS coated conductors considering quench origins - Proposal of criteria for stabilization and quench protection  

NASA Astrophysics Data System (ADS)

It has been considered that HTS coils are hard to be quenched because of high quench energy due to high critical temperature and high specific heat of HTS wires. Therefore, attention to quench protection was not much paid. However, HTS coils still have possibility to be quenched during operation by mainly the following two origins, (a) presence of non-recoverable local defects in the conductors and (b) temperature rise of long part of the conductor. Actually, severe quench accidents, such as burning coils, are occurring in various places as scales of HTS increased. Purposes of this paper are to study on behaviors of normal zone and hot spot temperature of wires during quench detect/energy dump sequence and to find criteria for the stability and quench protection. In the paper, criteria are proposed for stability and quench protection of HTS coils. A criterion for the stability is that a coil can be operated stably without a quench against defects in coil windings and that for quench protection is that a coil can be safely protected from damages caused by a quench due to temperature rise of long part of coil wires. The criteria are used as design rules for HTS coils.

Tsukamoto, Osami; Fujimoto, Yasutaka; Takao, Tomoaki

2014-09-01

34

Peculiarities on voltage - current characteristics of HTS tapes at overloading conditions cooled by liquid nitrogen  

NASA Astrophysics Data System (ADS)

Electro - technical devices are considered as the most prospective use for high temperature superconductors. For such devices the overload currents due to faults in grids are the operational reality. In these cases the fault currents may forcibly go to superconductors being sometimes dozens times more than the critical currents of HTS. Overloads are the working modes for fault current limiters also. To understand the behavior of HTS devices at overloads it is important to study voltage-current characteristics (VCC) of basic HTS tapes in real cooling conditions. The knowledge of VCC permits to model and to simulate properly HTS devices behavior at overloads. We performed the study of VCC of several HTS tapes at currents several times more than their critical ones. Both, 1-G and 2-G tapes were tested. There were found peculiarities or 'spikes' on VCC at rising currents that vanished at decaying currents. It was shown that such peculiarities are determined by the change of cooling conditions from the convective heat exchange to the nucleate boiling. Nucleate boiling activation and development times were determined. Their dependencies on heat release were measured. The data obtained can be used in simulation of heating of real superconducting devices at overload conditions.

Vysotsky, V. S.; Fetisov, S. S.; Sytnikov, V. E.

2008-02-01

35

Adhesion properties of MgO–ZrO 2 insulation coatings for 5 Tesla HTS coils  

Microsoft Academic Search

Self insulating substrate tapes (SIST) is the most promising insulation technique for high temperature MgO–ZrO2 coatings on Ag and AgMg sheathed Bi2Sr2Ca1Cu2Ox (Bi-2212) superconducting tapes and wires in applications of HTS\\/LTS coils and magnets. We have already reported successful results as to the synthesis, characterizations and applications of the insulation coatings using the SIST. In order to provide no electrical

E Celik; E Avci; Y. S Hascicek

2003-01-01

36

Next generation of HTS magnetic application: HTS bulk and coil interaction  

NASA Astrophysics Data System (ADS)

The next generation of HTS magnetic bearings (SMB) will operate at magnetic field excitation higher than permanent magnets (> 1.0 T). The new bearing type is capable to support heavy -load rotors of more than one ton mass. Using FEM we calculate the interaction of HTS bulk and 2G coil to achieve higher magnetic flux excitation and flux gradients of HTS bearings at temperatures of 50 - 60 K. The new total HTS bearing type multiplies the present 10 -15 N/cm2 force density obtained with PM's by a factor of 5 and passes the force properties of active magnetic bearings (AMB). HTS coil excitation is capable to increases the levitation forces to more than the present 10 kN level and reduces relative cooling and material effort per load. We design a magnetic bearing for HTS bulk -coil excitation.

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

2014-05-01

37

Wire Weight  

USGS Multimedia Gallery

Wire weight is lowered to water surface to measure stage at a site. Levels are made to the wire weights elevation from known benchmarks to ensure correct readings. This wire weight is located along the Missouri River in Bismarck, ND....

38

Analysis and experimental validation of an HTS linear synchronous propulsion prototype with HTS magnetic suspension  

NASA Astrophysics Data System (ADS)

A high temperature superconducting (HTS) linear propulsion system composed of a single-sided HTS linear synchronous motor (HTSLSM) in its middle and HTS magnetic suspension sub-systems on both sides has been developed. The HTSLSM uses an HTS bulk magnet array on the moving secondary, and the field-trapped characteristics of the HTS bulk using different magnetized methods have been measured and compared to identify their magnetization capability. In order to generate a large levitation force for the system, three different types of permanent magnet guideways (PMGs) have been numerically analyzed and experimentally verified to obtain an optimal PMG. Based on comprehensive experimental prototype tests, the results show that the HTS linear propulsion system can run with stable magnetic suspension having a constant air-gap length, and the thrust characteristics versus the exciting current, working frequency and the air-gap length have also been obtained. This work forms the basis for developing a practical HTS linear propulsion system by using HTS bulks both for propulsion and suspension.

Jin, Jianxun; Zheng, Luhai; Guo, Youguang; Xu, Wei; Zhu, Jianguo

2011-09-01

39

Basic Wiring.  

ERIC Educational Resources Information Center

This module is the first in a series of three wiring publications; it serves as the foundation for students enrolled in a wiring program. It is a prerequisite to either "Residential Wiring" or "Commercial and Industrial Wiring." The module contains 16 instructional units that cover the following topics: occupational introduction; general safety;…

Kaltwasser, Stan; And Others

40

A Test of HTS Power Cable in a Sweeping Magnetic Field  

SciTech Connect

Short sample HTS power cable composed of multiple 344C-2G strands and designed to energize a fast-cycling dipole magnet was exposed to a sweeping magnetic field in the (2-20) T/s ramping rate. The B-field orientation toward the HTS strands wide surface was varied from 0{sup 0} to 10{sup 0}, in steps of 1{sup 0}. The test arrangement allowed measurement of the combined hysteresis and eddy current power losses. For the validity of these measurements, the power losses of a short sample cable composed of multiple LTS wire strands were also performed to compare with the known data. The test arrangement of the power cable is described, and the test results are compared with the projections for the eddy and hysteresis power losses using the fine details of the test cable structures.

Piekarz, H.; Hays, S.; Blowers, J.; Shiltsev, V.; /Fermilab

2011-11-29

41

Experimental study of thrusts of a cylindrical linear synchronous motor with an HTS coil magnet as the excitation system  

NASA Astrophysics Data System (ADS)

The thrusts of a cylindrical linear synchronous motor with an HTS coil magnet as the excitation system were measured the first time and will be presented in this paper. The HTS coil magnet is made of second generation YBCO wire. The coil is a double pancake coil consisting of 34 turns wire. The inner diameter, outer diameter and height of the coil are 20, 30 and 13 mm, respectively. The armature of the motor is three phases, and the inner diameter is 40 mm. It is made of copper windings. With a direct current of 40 A for the HTS coil magnet and a RMS current of 10 A for the armature, a peak thrust of 3.8 N was measured at the temperature of 77 K and a radial gap of 5 mm between the armature and the excitation system. Effects of armature current, coil current, running time, magnetizers and seams between magnetizers were also studied. In the experiments, the peak thrusts of different types of HTS coil magnets were about from 1.3 times to 8 times as strong as the peak thrust of the coreless coil magnet under the same conditions.

Duan, Wanqing; Yan, Zhongming; Luo, Wenbo; Zhang, Peixing; Gui, Zhixing; Wang, Zhiquan; Wang, Yu

2015-01-01

42

Digital Wires  

NASA Astrophysics Data System (ADS)

We study hardware implementations of cellular automata as reliable, adjustable, and secure commication lines. We discuss energy efficient digital wires on a nano-scale, all-optical digital wires, and digital wires as power lines and present performance data of a prototype digital wire, a six cells wide and ten cells long Boolean network. We show that digital wires have the following advantages: (i) Fixed pulse shape (pulses have a rectangular shape with a constant height and a constant width and produce no echos); (ii) Robust against electric smog. Digital wires based on semiconductor technology are effectively inert against electro-magnetic radiation, except for low-frequency radiation (heat) and high frequency radiation (X-rays). Digital wires based on plasma technology have in addition a very high tolerance for heat and X-rays. In digital wire the pulse speed can be rapidly adjusted. Signals on digital wires can be encrypted. Some digital wires can be used as general purpose computers. The data and the code are the input of the wire. Then both travel along the wire and `collide'. The collision is the computation. The result travels to the end of the wire, for further processing, as parallel input by a CPU, an actuator, or another digital wire.

Brown, Benny; Hubler, Alfred

2009-03-01

43

A Unified and Automatic Approach Of Mandarin HTS System   

E-print Network

Most studies on Mandarin HTS (HMM-based text-to-speech system) have taken the initial/final as the basic acoustic units. It is, however, challenging to develop a multilingual HTS in a uniformed and consistent way since ...

Guan, Yong; Tian, Jilei; Wu, Yi-Jian; Yamagishi, Junichi; Nurminen, Jani

2010-01-01

44

R&D ERL: HTS Solenoid  

SciTech Connect

An innovative feature of the ERL project is the use of a solenoid made with High Temperature Superconductor (HTS) with the Superconducting RF cavity. The HTS solenoid design offers many advantages because of several unique design features. Typically the solenoid is placed outside the cryostat which means that the beam gets significantly defused before a focusing element starts. In the current design, the solenoid is placed inside the cryostat which provides an early focusing structure and thus a significant reduction in the emittance of the electron beam. In addition, taking full advantage of the high critical temperature of HTS, the solenoid has been designed to reach the required field at {approx}77 K, which can be obtained with liquid nitrogen. This significantly reduces the cost of testing and allows a variety of critical pre-tests which would have been prohibitively expensive at 4 K in liquid helium because of the additional requirements of cryostat and associated facilities.

Gupta, R.; Muratore, J.; Plate, S.

2010-01-01

45

US effort on HTS power transformers  

NASA Astrophysics Data System (ADS)

Waukesha Electric Systems has been working in HTS power transformers development program under the auspices of US Government Department of Energy since 1994. This presentation will describe various milestones for this program and program history along with the lessons learned along the way. Our motivations for working on this development program based on man benefits offered by HTS power transformers to power delivery systems will be discussed. Based on various issues encountered during execution of many HTS projects, DOE has set up an independent program review process that is lead by team of experts. This team reviews are integral part of all DOE HTS projects. Success of all projects would be greatly enhanced by identifying critical issues early in the program. Requiring appropriate actions to mitigate the issues before processing further will lead to proactive interrogation and incorporation of expert’s ideas in the project plans. Working of this review process will be also described in this presentation. Waukesha Electric Systems team including: Superpower-Inc, Oak Ridge National Laboratory, University of Houston Center for Superconductivity and Southern California Edison company was awarded a cost share grant by US Government in 2010 for development of a fault current limiting HTS power transformer. This multi year’s program will require design, manufacture, installation, and monitoring of a 28 MVA tree phase transformer installed at Irvine CA. Smart Grid demonstration site. Transformer specifications along with requirements for fault current limiting and site requirement will be discussed. Design and development of various sub systems in support of this program including: HTS conductor performance specification, Dielectric system design approach, Dewar development for containing phase assemblies, cryo-cooling system design approach, etc. will be described. Finally; overall program schedule, critical milestone events, test plans and progress to date will be reported.

Mehta, S.

2011-11-01

46

RADIATION RESISTANT HTS QUADRUPOLES FOR RIA.  

SciTech Connect

Extremely high radiation, levels with accumulated doses comparable to those in nuclear reactors than in accelerators, and very high heat loads ({approx}15 kw) make the quadrupole magnets in the fragment separator one of the most challenging elements of the proposed Rare Isotope Accelerator (RIA). Removing large heat loads, protecting the superconducting coils against quenching, the long term survivability of magnet components, and in particular, insulation that can retain its functionality in such a harsh environment, are the major challenges associated with such magnets. A magnet design based on commercially available high temperature superconductor (HTS) and stainless steel tape insulation has been developed. HTS will efficiently remove these large heat loads and stainless steel can tolerate these large radiation doses. Construction of a model magnet has been started with several coils already built and tested. This paper presents the basic magnet design, results of the coil tests, the status and the future plans. In addition, preliminary results of radiation calculations are also presented.

GUPTA,R.; ANERELLA,M.; HARRISON,M.; ET AL.

2004-10-03

47

Human rigHts advocacy in action  

E-print Network

18 Brave new world 22 thought that counts 27 In pictures snapshots 5 taken 29 Regulars BristolHuman rigHts advocacy in action Lives weLL Lived: a new age of animaL weLfare aLzHeimer's: no smoke in pieces 2 & 17 alumni in the news 3 Bristol and beyond 10 Summer2012 Contents 29 2 new solutions to old

Bristol, University of

48

Residential Wiring.  

ERIC Educational Resources Information Center

The second in a series of three curriculum packages on wiring, these materials for a five-unit course were developed to prepare postsecondary students for entry-level employment in the residential wiring trade. The five units are: (1) blueprint reading and load calculations; (2) rough-in; (3) service; (4) trim out and troubleshooting; and (5) load…

Taylor, Mark

49

Wire chamber  

DOEpatents

A wire chamber or proportional counter device, such as Geiger-Mueller tube or drift chamber, improved with a gas mixture providing a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor.

Atac, Muzaffer (Wheaton, IL)

1989-01-01

50

Design and experimental results for Albany HTS cable  

Microsoft Academic Search

The Albany Project plans to install a 350 m High Temperature Superconducting (HTS) cable in the power grid of the Niagara Mohawk Power Company to carry 800 Arms at 34.5 kV. The type of the cable has 3 HTS cores in one cryostat with Bi-2223 used for HTS conductor and shield layers. The three cores are housed within double SUS

T. Masuda; H. Yumura; M. Watanabe; H. Takigawa; Y. Ashibe; C. Suzawa; T. Kato; Y. Yamada; K. Sato; S. Isojima; C. Weber; A. Dada; J. R. Spadafore

2005-01-01

51

MODELING OF HTS APPLICATIONS USING EMTP WITH FLUX-PINNING SCALING MODELS FOR PRACTICAL HTS SUPERCONDUCTORS  

Microsoft Academic Search

The EMTP software (Electromagnetic Transient Program) for modeling the behavior of electric power systems is commonly used to obtain the transient response of system disturbances, for example caused by fault currents. We have developed specific modules describing practical HTS materials that can be used to describe new architectures involving superconducting power devices, for example fault current limiters. These modules include

J. R. Cave; V. K. Sood

2008-01-01

52

Modeling of Hts Applications Using Emtp with Flux-Pinning Scaling Models for Practical Hts Superconductors  

Microsoft Academic Search

The EMTP software (Electromagnetic Transient Program) for modeling the behavior of electric power systems is commonly used to obtain the transient response of system disturbances, for example caused by fault currents. We have developed specific modules describing practical HTS materials that can be used to describe new architectures involving superconducting power devices, for example fault current limiters. These modules include

J. R. Cave; V. K. Sood

2008-01-01

53

Wire Wise.  

ERIC Educational Resources Information Center

Discusses how today's technology is encouraging schools to invest in furnishings that are adaptable to computer use and telecommunications access. Explores issues concerning modularity, wiring management, ergonomics, durability, price, and aesthetics. (GR)

Swanquist, Barry

1998-01-01

54

UN Wire  

NSDL National Science Digital Library

Provided by the UN Foundation, UN Wire is a new "daily news summary covering the United Nations, global affairs and key international issues." Users interested in the UN or global affairs will find UN Wire an excellent resource for quick, concise accounts of the day's major stories. Each day, UN Wire covers issues such as UN Affairs; Health; Women, Children, and Population; Environment; Trade; Humanitarian Aid; Human Rights; and Peacekeeping. Typical entries include a few short paragraphs and direct links to the original news source and/or related resources. Free registration is required and users can subscribe for free daily email summaries of the headlines. UN Wire should be available for email delivery in complete form in the next few months.

1999-01-01

55

Stretching Wires  

NSDL National Science Digital Library

In this activity, learners determine the elastic and plastic properties of different types of metal wires. Learners discover that wires of the same gauge, but made of different metals, typically support different loads (masses) before going through the elastic to plastic transition. Learners also learn the difference between elastic deformation, which is recoverable after the load is removed, and plastic deformation, which is not recoverable. Note: one way to save time on this lab is to have different groups test different metals.

2013-01-04

56

Thermodynamic optimization of conduction-cooled HTS current leads  

Microsoft Academic Search

A theoretical optimization is performed for the conduction-cooling method of high Tc superconductor (HTS) current leads, which can be applied to the superconducting systems cooled directly by cryogenic refrigerators without liquid helium. The current lead is a series combination of a normal metal conductor at the warmer part and a HTS at the colder part, and is cooled by a

Ho-Myung Chang; Steven W. Van Sciver

1998-01-01

57

HTS current leads for the LHC magnet powering system  

Microsoft Academic Search

Among the different applications of the emerging High Temperature Superconducting (HTS) technology, current leads represent a key development component. In this field the state of maturity of the conductor is such as to satisfy both a wide range of design requirements and those of economic viability. The LHC superconducting magnets will be powered through HTS current leads transferring in total

Amalia Ballarino

2002-01-01

58

University Wire  

NSDL National Science Digital Library

University Wire is a daily Internet news service for college newspapers. Included are a story of the day, a large list of pointers to Internet resources in topics such as current headlines, politics, medicine and health, and women's resources; a "Kopyedit Korner," with pointers to writing reference materials; a placement center with job openings lists for college journalists; a large selection of pointers to college newspapers; and pointers to general circulation newspapers. Pointers to student and professional journalism organizations, as well as a calendar of journalism related events, are also provided. University Wire is a service of The Main Quad.

59

Processing, fabrication, and demonstration of HTS integrated microwave circuits  

NASA Astrophysics Data System (ADS)

High temperature superconductor (HTS) devices can and will improve the performance of ESM and shared aperture receiver systems. For the near term the most promising candidate for the reference channelized cued ESM receiver system is an HTS IF Delsy line that can provide 200 nanoseconds of delay across a 3 to 5 GHz band. Such a delay line can improve sensitivity by 1 to 2 dB while providing about a 6 dB improvement in two tone dynamic range. Perhaps even of greater importance is that the low device loss combined with the elimination of multiple amplifiers previously needed to overcome loss can significantly improve the amplitude and phase tracking of the delay lines. In future systems it is unlikely that a single HTS device will be employed. Rather, it is more likely that large portions of the RF architecture will be placed in a cooler as a means of achieving performance and cost advantages. This is thought to include an HTS front-end, conventional IF amplifier, and HTS IF receivers. Looking even further in the future it is likely that entire HTS receivers will be remotely located with their HTS antennas and only digits will be returned to central for processing.

Wagner, G. R.; Talisa, S. H.; Talvacchio, J.

1994-09-01

60

Recent developments in processing HTS silver-clad Bi-2223 tapes, coils and test magnets  

SciTech Connect

Considerable progress has been made in fabricating Bi-2223 high temperature superconductor (HTS) wires and tapes with high critical current densities that are attractive for electric power and high-field magnet applications. Powder-in-tube processed silver-clad Bi-2223 short tape samples, small coils and test magnets have been fabricated and measured at liquid nitrogen (77K), pumped liquid nitrogen (64 K), liquid neon (27K) and liquid helium (4.2K) temperatures. Optimization of thermo-mechanical process parameters have yielded J{sub c}`s in the superconducting core > 4.0 {times} 10{sup 4} A/cm{sup 2} at 77K zero field and > 2.0 {times} 10{sup 5} A/cm{sup 2} at 4.2K, zero field. Long lengths (up to 70 m) of mono-core conductors were fabricated and tested to carry significant amounts of current (23 A, {approximately}15,000 A/cm{sup 2}) at liquid nitrogen temperature. Recent test magnets assembled from pancake wound coils were measured to generate magnetic fields as high as 2.6, 1.8 and 0.36 Tesla at 4.2K, 27K and 77K respectively. These results show promise towards practical utilization of HTS materials.

Haldar, P.; Hoehn, J.G. Jr. [Intermagnetics General Corp., Guilderland, NY (United States); Motowidlo, L.R. [IGC Advanced Superconductors, Inc., Waterbury, CT (United States); Balachandran, U. [Argonne National Lab., IL (United States); Iwasa, Y.; Yunus, M. [Massachusetts Inst. of Technology, Cambridge, MA (United States). Francis Bitter National Magnet Lab.

1993-10-01

61

HTS coil development and fabrication. Final report  

SciTech Connect

The objective of this subtask (Task 2C) was to develop high-temperature superconductor (HTS) coil technology aimed specifically at superconducting generator applications. Bi-2223 tape produced in a separate subtask (Task 2A) was first wound and tested in a small circular coil. This small coil winding experience led the authors to develop a tape strengthening method using a lamination process and to develop a turn insulation method using a paper wrap process. A prototype racetrack coil was wound using 2500 feet of the laminated and insulated Bi-2223 tapes. The racetrack coil was cooled to 20K in a vacuum dewar using a unique closed-cycle helium gas refrigeration system.

Herd, K.G.; Salasoo, L.; Ranze, R. [and others

1996-10-01

62

Critical State Modelling of Crossed Field Demagnetisation in HTS Materials  

E-print Network

, University of Oxford, UK Department of Mathematics, Ben Gurion University of the Negev, Israel § Department thus enables the creation of high field magnets using bulk HTS materials. It has already been shown

Prigozhin, Leonid

63

Design of a Probe for Strain Sensitivity Studies of Critical Current Densities in SC Wires and Tapes  

SciTech Connect

The design of a variable-temperature probe used to perform strain sensitivity measurements on LTS wires and HTS wires and tapes is described. The measurements are intended to be performed at liquid helium temperatures (4.2 K). The wire or tape to be measured is wound and soldered on to a helical spring device, which is fixed at one end and subjected to a torque at the free end. The design goal is to be able to achieve {+-} 0.8 % strain in the wire and tape. The probe is designed to carry a current of 2000A.

Dhanaraj, N.; Barzi, E.; Turrioni, D.; Rusy, A.; Lombardo, V.; /Fermilab

2011-07-01

64

Rotor compound concept for designing an industrial HTS synchronous motor  

NASA Astrophysics Data System (ADS)

Recently, producing power with smaller amount of losses become as a goal in our daily life. Today, large amount of energy waste in power networks all around the world. The main reason is “resistive electric equipments” of power networks. Since early 1980s, simultaneous with the development of high temperature superconductive (HTS) technology, superconductors gently attracted the mankind attentions. Using superconductive equipments instead of conventional resistive ones are result in salient electric loss reduction in power systems. Especially to reduce losses in power networks superconductive industrial rotating machines can potentially perform a significant role. In early recent century, first generation of HTS rotating machines was born. But unfortunately they have long way to penetrate the commercial markets yet. In HTS rotating machines the conventional copper made windings are replaced with the HTS superconductors. In this paper an industrial HTS synchronous motor with YBCO coated conductor field windings was designed. As a new approach, model was equipped with a compound rotor that includes both magnetic and non-magnetic materials. So, large amount of heavy iron made part was replaced by light non-magnetic material such as G-10 fiberglass. Furthermore, in this structure iron loss in rotor could be reduced to its lowest value. Also less weight and more air gap energy density were the additional advantages. Regarding zero electric loss production in field windings and less iron loss in rotor construction, this model potentially is more effective than the other iron made HTS motors.

Kashani, M.; Hosseina, M.; Sarrafan, K.; Darabi, A.

2013-06-01

65

Superconducting wires  

SciTech Connect

The requirement of high critical current density has prompted extensive research on ceramic processing of high-T/sub c/ superconductors. An overview of wire fabrication techniques and the limitations they impose on component design will be presented. The effects of processing on microstructure and critical current density will also be discussed. Particle alignment has been observed in extruded samples which is attributed to high shear stresses during plastic forming. Composites of superconductor and silver in several configurations have been made with little deleterious effect on the superconducting properties. 35 refs., 2 figs., 1 tab.

Lanagan, M.T.; Poeppel, R.B.; Singh, J.P.; Dos Santos, D.I.; Lumpp, J.K.; Dusek, J.T.; Goretta, K.C.

1988-06-01

66

The installation and test results for Albany HTS cable project  

NASA Astrophysics Data System (ADS)

Albany HTS cable project is going on with the support of US Federal and New York States. The HTS cables included the Bi2223 tapes sintered by CT-OP (controlled over-pressure) process has 34.5 kV and 800 A capacity. The cable system was manufactured in Japan, and shipped to Albany. A 320 m cable and a 30 m cable were installed into the conduits under the ground. Subsequently, a splice box was assembled in the vault, and two terminations were connected to the HTS cable on the ground. Cryogenic refrigeration system was also mounted at the site by BOC. Initial cooling process was conducted as measuring distributed temperatures along the cable. The results of off-grid test, i.e. measuring heat loss, pressure loss, critical current, and DC withstand test, were carried out successfully. HTS cable system was connected to the real grid on 20 July 2006. The cable has been operated stably for 3 months as monitored by Remote Operation Center of BOC. This report outlines the installation and test results on Albany HTS cable project.

Takigawa, H.; Yumura, H.; Masuda, T.; Watanabe, M.; Ashibe, Y.; Itoh, H.; Suzawa, C.; Hirose, M.; Yatsuka, K.; Sato, K.; Isojima, S.

2007-10-01

67

Role of HTS devices in greenhouse gas emission reduction  

NASA Astrophysics Data System (ADS)

By applying high temperature superconductors (HTS) in generators, transformers and synchronous motors it is possible to improve their efficiency. Higher efficiency saves electrical energy and thus reduces greenhouse gas (GHG) emissions as well. The reduction of GHG emissions is becoming a topical issue due to the Kyoto Protocol which requires the European Union (EU) to reduce its emissions by 8% from the 1990 levels between 2008 and 2012. This environmental viewpoint can accelerate the commercialization of HTS applications if certain efficiency and sufficiently large power range are reached. In this paper, a detailed study about the replacement of existing devices by HTS ones is made in order to find the efficiency level and the power range where HTS becomes competitive. Finland is taken, as an example of an EU country, to present accurate figures of saved electricity. The structure of energy production and consumption was investigated and the emission data from different types of power plants were screened. The potential savings were allocated to the reduced usage of coal. Finally, an expanded view towards the possible emissions reduction gained by superconducting technology in the whole EU is presented. A market penetration model was introduced to investigate the time-scale in which conventional devices can be replaced with HTS devices.

Hartikainen, Teemu; Lehtonen, Jorma; Mikkonen, Risto

2003-08-01

68

HTS power lead testing at the Fermilab magnet test facility  

SciTech Connect

The Fermilab Magnet Test Facility has tested high-temperature superconductor (HTS) power leads for cryogenic feed boxes to be placed at the Large Hadron Collider (LHC) interaction regions and at the new BTeV C0 interaction region of the Fermilab Tevatron. A new test facility was designed and operated, successfully testing 20 pairs of HTS power leads for the LHC and 2 pairs of HTS power leads for the BTeV experiment. This paper describes the design and operation of the cryogenics, process controls, data acquisition, and quench management systems. Results from the facility commissioning are included, as is the performance of a new insulation method to prevent frost accumulation on the warm ends of the power leads.

Rabehl, R.; Carcagno, R.; Feher, S.; Huang, Y.; Orris, D.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.; /Fermilab

2005-08-01

69

Targeting chemical inputs and optimising HTS for agrochemical discovery.  

PubMed

In vivo high throughput screening (HTS) has been adopted by most of the larger crop protection companies as an important tool for the discovery of new agrochemicals. There has been a paradigm shift in capabilities from screening a few thousand compounds a year to several hundred thousand and the quantity of screening sample required has fallen dramatically. The unifying goal now bringing together screens and inputs is the need to maximise the flow of useful information from HTS and thereby minimise the time taken to discover robust leads and new products. This review examines the positive changes that have occurred towards targeted design and selection of chemical inputs for agrochemical discovery over the last ten years and corresponding developments in HTS assays, data analysis and the logistics of compound storage and dispensing. PMID:16305355

Smith, Stephen C; Delaney, John S; Robinson, Michael P; Rice, Martin J

2005-11-01

70

Transposed-Cable Coil & Saddle Coils of HTS for Rotating Machines: Test Results at 30 K  

Microsoft Academic Search

We have manufactured and tested new HTS coil configurations in order to extend the range of rotating machines to which HTS tapes can be applied. The rotors of large utility generators require operating currents of several kA, which can be achieved by connecting several HTS tapes in parallel in a transposed cable. Design of a generator poses questions on winding

Marijn P. Oomen; Martino Leghissa; Norbert Proelss; Heinz-Werner Neumueller

2009-01-01

71

13000 A HTS Current Leads for the LHC Accelerator:From Conceptual Design to Prototype Validation  

Microsoft Academic Search

The main dipole and quadrupole circuits of the LHC accelerator will be fed via 13000 A High Temperature Superconducting (HTS) current leads. To validate the design and technological choices prior to launching the industrial production of the serial components, CERN has designed and assembled in-house a pair of 13000 A HTS current leads. The HTS part of the lead consists

A. Ballarino; S. Mathot; D. Milani

2004-01-01

72

AN UNIFIED AND AUTOMATIC APPROACH OF MANDARIN HTS SYSTEM Yong Guan1, 2  

E-print Network

AN UNIFIED AND AUTOMATIC APPROACH OF MANDARIN HTS SYSTEM Yong Guan1, 2 , Jilei Tian2 , Yi-Jian Wu3&D, Finland ABSTRACT Most studies on Mandarin HTS (HMM-based text-to-speech system) have taken the initial a phoneme based Mandarin HTS system, which has been systematically evaluated by comparing

Edinburgh, University of

73

Experimental and numerical investigations on permanent magnet method for measuring critical current density in HTS films  

Microsoft Academic Search

The permanent magnet method measuring a critical current density in high temperature superconducting (HTS) thin films was experimentally and numerically investigated. The permanent magnet method was a contactless and nondestructive method for measuring a critical current density of HTS films. A permanent magnet was brought closer to an HTS thin film. A load sensor measured the electromagnetic force acting on

S. Ikuno; T. Takayama; A. Kamitani; K. Umetsu; A. Saito; S. Ohshima

2009-01-01

74

Cryogenic Cooling System By Natural Convection Of Subcooled Liquid Nitrogen For HTS Transformers  

Microsoft Academic Search

A new concept of thermal design to optimize the operating temperature of HTS magnets is developed, aiming simultaneously for compactness and efficiency. The optimization procedure seeks the operating temperature to minimize the power consumption in steady state. This procedure includes the modeling of the critical properties of HTS conductors, the dimensions of HTS windings, the heat transfer analysis for cooling

Yeon Suk Choi

2004-01-01

75

Prototype of a Disc-Type HTS Bearing  

NASA Astrophysics Data System (ADS)

A prototype of a rotational machine with two HTS bearings supporting a rotor without a mechanical contact has been designed, manufactured and tested. An arrangement of HTS elements with 180-g total mass provide stable suspension of a 3.6-kg rotor with 1.0-mm operating gap. The maximal load capability of the bearing was measured to be 220 N in the radial direction and 150 N in the axial. The ratio of the radial load capability to the mass of superconductors exceeded 120. The maximum rotation frequency was 14500 rpm.

Polushchenko, O. L.; Nizhelskiy, N. A.; Matveev, V. A.; Gerdi, V. N.

76

Ultra-High Performance, High-Temperature Superconducting Wires via Cost-effective, Scalable, Co-evaporation Process  

NASA Astrophysics Data System (ADS)

Long-length, high-temperature superconducting (HTS) wires capable of carrying high critical current, Ic, are required for a wide range of applications. Here, we report extremely high performance HTS wires based on 5 ?m thick SmBa2Cu3O7 - ? (SmBCO) single layer films on textured metallic templates. SmBCO layer wires over 20 meters long were deposited by a cost-effective, scalable co-evaporation process using a batch-type drum in a dual chamber. All deposition parameters influencing the composition, phase, and texture of the films were optimized via a unique combinatorial method that is broadly applicable for co-evaporation of other promising complex materials containing several cations. Thick SmBCO layers deposited under optimized conditions exhibit excellent cube-on-cube epitaxy. Such excellent structural epitaxy over the entire thickness results in exceptionally high Ic performance, with average Ic over 1,000 A/cm-width for the entire 22 meter long wire and maximum Ic over 1,500 A/cm-width for a short 12 cm long tape. The Ic values reported in this work are the highest values ever reported from any lengths of cuprate-based HTS wire or conductor.

Kim, Ho-Sup; Oh, Sang-Soo; Ha, Hong-Soo; Youm, Dojun; Moon, Seung-Hyun; Kim, Jung Ho; Dou, Shi Xue; Heo, Yoon-Uk; Wee, Sung-Hun; Goyal, Amit

2014-04-01

77

Ultra-High Performance, High-Temperature Superconducting Wires via Cost-effective, Scalable, Co-evaporation Process  

PubMed Central

Long-length, high-temperature superconducting (HTS) wires capable of carrying high critical current, Ic, are required for a wide range of applications. Here, we report extremely high performance HTS wires based on 5??m thick SmBa2Cu3O7 ? ? (SmBCO) single layer films on textured metallic templates. SmBCO layer wires over 20 meters long were deposited by a cost-effective, scalable co-evaporation process using a batch-type drum in a dual chamber. All deposition parameters influencing the composition, phase, and texture of the films were optimized via a unique combinatorial method that is broadly applicable for co-evaporation of other promising complex materials containing several cations. Thick SmBCO layers deposited under optimized conditions exhibit excellent cube-on-cube epitaxy. Such excellent structural epitaxy over the entire thickness results in exceptionally high Ic performance, with average Ic over 1,000?A/cm-width for the entire 22 meter long wire and maximum Ic over 1,500?A/cm-width for a short 12?cm long tape. The Ic values reported in this work are the highest values ever reported from any lengths of cuprate-based HTS wire or conductor. PMID:24752189

Kim, Ho-Sup; Oh, Sang-Soo; Ha, Hong-Soo; Youm, Dojun; Moon, Seung-Hyun; Kim, Jung Ho; Dou, Shi Xue; Heo, Yoon-Uk; Wee, Sung-Hun; Goyal, Amit

2014-01-01

78

Fabrication and wire extrusion of ceramic superconductors  

SciTech Connect

Many applications of high-temperature superconductors (HTSs) will depend on the ability to fabricate these materials into long lengths with suitable electrical and mechanical properties maintained over the entire length. The program described in this paper is focused on improvement of the relevant material properties of HTSs and on development of fabrication methods that can be transferred to industry for production of commercial conductors. Our research has resulted in advances in fabrication methods that improve the performance of long lengths of polycrystalline HTS wires and tapes. We have examined the Y-Ba-Cu-O (YBCO), Bi-Sr-Ca-Cu-O (BSCCO), and Tl- Ba-Ca-Cu-O (TBCCO) classes of HTSs. Significant results from our research and work by contemporaries are reported in the various sections of the paper. 28 refs.

Poeppel, R.B.; Balachandran, U.; Singh, J.P.; Dusek, J.T.; Picciolo, J.J.; Dorris, S.E.; Lanagan, M.T.; Goretta, K.C.; Youngdahl, C.A.; Hull, J.R.

1991-05-01

79

Windows: Life after Wire.  

ERIC Educational Resources Information Center

Although wired glass is extremely common in school buildings, the International Building Code adopted new standards that eliminate the use of traditional wired glass in K-12 schools, daycare centers, and athletic facilities. Wired glass breaks easily, and the wires can cause significant injuries by forming dangerous snags when the glass breaks.…

Razwick, Jerry

2003-01-01

80

The Future of Wires  

Microsoft Academic Search

Concern about the performance of wires in scaled technologies has led to research exploring other communication methods. This paper examines wire and gate delays as technologies migrate from 0.18- m to 0.035- m feature sizes to better understand the magni- tude of the wiring problem. Wires that shorten in length as technolo- gies scale have delays that either track gate

RON HO; KENNETH W. MAI; MARK A. HOROWITZ

1999-01-01

81

Numerical assessment of efficiency and control stability of an HTS synchronous motor  

NASA Astrophysics Data System (ADS)

A high temperature superconducting (HTS) permanent magnet synchronous motor (PMSM) is designed and developed in Cambridge University. It is expected to become cost competitive with the conventional PMSM owing to its high efficiency, high power density, high torque density, etc. The structure and parameters of HTS PMSM are detailed. Both AC losses by transport current and applied filed in stator armature winding of HTS PMSM are also analyzed. Computed and simulated results of the characteristics of the HTS PMSM and conventional PMSM are compared. The improvement on stability of direct torque control (DTC) on the HTS PMSM is estimated, and proved by simulation on Matlab/Simulink.

Xian, Wei; Yuan, Weijia; Coombs, T. A.

2010-06-01

82

Recent advances in high-temperature superconductor wire fabrication and applications development  

SciTech Connect

In this paper, recent advances in fabrication of HTS wires are summarized, and detailed discussion is provided for developments in near- and intermediate-term applications. Near-term applications, using presently obtainable current densities, include: liquid-nitrogen depth sensors, cryostat current leads, and magnetic bearings. Intermediate-term applications, using current densities expected to be available in the near future include fault-current limiters and short transmission lines. 25 refs.

Hull, J.R.; Uherka, K.L.

1992-08-01

83

Recent advances in high-temperature superconductor wire fabrication and applications development  

SciTech Connect

In this paper, recent advances in fabrication of HTS wires are summarized, and detailed discussion is provided for developments in near- and intermediate-term applications. Near-term applications, using presently obtainable current densities, include: liquid-nitrogen depth sensors, cryostat current leads, and magnetic bearings. Intermediate-term applications, using current densities expected to be available in the near future include fault-current limiters and short transmission lines. 25 refs.

Hull, J.R.; Uherka, K.L.

1992-01-01

84

Issues relating to airborne applications of HTS SQUIDs  

Microsoft Academic Search

Airborne application of HTS SQUIDs is the most difficult environment for their successful deployment. In order to operate with the sensitivity required for a particular application, there are many issues to be addressed such as the need for very wide dynamic range electronics, motion noise elimination, immunity to large changing magnetic fields and cultural noise sources. This paper reviews what

C. P. Foley; K. E. Leslie; R. A. Binks; S. H. K. Lam; J. Du; D. L. Tilbrook; E. E. Mitchell; J. C. Macfarlane; J. B. Lee; R. Turner; M. Downey; A. Maddever

2002-01-01

85

The development of 4 m HTS power cable  

Microsoft Academic Search

Superconducting cables offer the advantages of lower loss, lighter weight and smaller dimensions, as compared to conventional cables. A 4 m, 2 kA, AC, HTS cable system was developed for the purpose of study. The cable conductor was made of Bi-2223 tapes. A space maintained as a vacuum between two corrugated stainless steel tubes functions as a cryostat surrounding the

Bo Hou; Haixia Xi; Feng Yuan; Yong Zhang; Ying Xin; Yanfang Bi; Songtao Wu; Huaikuang Ding; Jing Shi

2004-01-01

86

HTS DC Transmission Line for Megalopolis Grid Development  

NASA Astrophysics Data System (ADS)

Using of HTS AC and DC cables in electric power grids allows increasing of the transferred power, losses diminishing, decreasing of exclusion zone areas, the enhancement of the environmental conditions and fire/explosion safety of electric power systems. However, the use of DC superconducting cable lines together with converters brings additional advantages as reduction of losses in cables and suitable lowering of refrigerating plant capacity, as well as the realization of the function of short-circuit currents limitation by means of the appropriate setting of converter equipment. Russian Federal Grid Company and its R&D Center started the construction of the DC HTS power transmission line which includes the cable itself, cryogenic equipment, AC/DC converters, terminals and cable coupling boxes. This line will connect two substations in Saint-Petersburg - 330 kV "Centralnaya" and 220 kV "RP-9". The length of this HTS transmission line will be about 2500 meters. Nowadays are developed all the elements of the line and technologies of the cable manufacturing. Two HTS cable samples, each 30 m length, have been made. This paper describes the results of cables tests.

Kopylov, S.; Sytnikov, V.; Bemert, S.; Ivanov, Yu; Krivetskiy, I.; Romashov, M.; Shakaryan, Yu; Keilin, V.; Shikov, A.; Patrikeev, V.; Lobyntsev, V.; Shcherbakov, V.

2014-05-01

87

Phonons and charge-transfer excitations in HTS superconductors  

SciTech Connect

Some of the experimental and theoretical evidence implicating phonons and charge-transfer excitations in HTS superconductors is reviewed. It is suggested that superconductivity may be driven by a synergistic interplay of (anharmonic) phonons and electronic degrees of freedom (e.g., charge fluctuations, excitons). 47 refs., 5 figs.

Bishop, A.R.

1989-01-01

88

Large-scale HTS bulks for magnetic application  

NASA Astrophysics Data System (ADS)

ATZ Company has constructed about 130 HTS magnet systems using high-Tc bulk magnets. A key feature in scaling-up is the fabrication of YBCO melts textured multi-seeded large bulks with three to eight seeds. Except of levitation, magnetization, trapped field and hysteresis, we review system engineering parameters of HTS magnetic linear and rotational bearings like compactness, cryogenics, power density, efficiency and robust construction. We examine mobile compact YBCO bulk magnet platforms cooled with LN2 and Stirling cryo-cooler for demonstrator use. Compact cryostats for Maglev train operation contain 24 pieces of 3-seed bulks and can levitate 2500-3000 N at 10 mm above a permanent magnet (PM) track. The effective magnetic distance of the thermally insulated bulks is 2 mm only; the stored 2.5 l LN2 allows more than 24 h operation without refilling. 34 HTS Maglev vacuum cryostats are manufactured tested and operate in Germany, China and Brazil. The magnetic levitation load to weight ratio is more than 15, and by group assembling the HTS cryostats under vehicles up to 5 t total loads levitated above a magnetic track is achieved.

Werfel, Frank N.; Floegel-Delor, Uta; Riedel, Thomas; Goebel, Bernd; Rothfeld, Rolf; Schirrmeister, Peter; Wippich, Dieter

2013-01-01

89

The future of wires  

Microsoft Academic Search

Concern about the performance of wires wires in scaled technologies has led to research exploring other communication methods. This paper examines wire and gate delays as technologies migrate from 0.18-?m to 0.035-?m feature sizes to better understand the magnitude of the the wiring problem. Wires that shorten in length as technologies scale have delays that either track gate delays or

RON HO; KENNETH W. MAI; MARK A. HOROWITZ

2001-01-01

90

Stretched Wire Mechanics  

SciTech Connect

Stretched wires are beginning to play an important role in the alignment of accelerators and synchrotron light sources. Stretched wires are proposed for the alignment of the 130 meter long LCLS undulator. Wire position technology has reached sub-micron resolution yet analyses of perturbations to wire straightness are hard to find. This paper considers possible deviations of stretched wire from the simple 2-dimensional catenary form.

Bowden, Gordon; /SLAC

2005-09-06

91

The characteristics of trapped magnetic flux inside bulk HTS in the Mixed-? levitation system  

NASA Astrophysics Data System (ADS)

In this paper we propose a new experimental method to investigate the principle of ‘Mixed-?’ levitation systems. To confirm our claim, we measured the attractive force and the variation of flux passing through both, the HTS sample and the face surface of iron yoke, when the yoke is approached/retreated to the surface of field-cooled HTS sample. It is revealed that when the diameter of the yoke is less than the diameter of the HTS, in the small gap by reducing the gap, the flux which passes through the face surface of the yoke and consequently the attractive force will decrease. Therefore, stable levitation is achievable. However, when the diameter of yoke is equal to the diameter of the HTS, the magnetic flux will not decrease for a reducing gap and stable levitation is unfeasible. Briefly, stable levitation is achievable when the yoke diameter is less than the HTS’s diameter. Additionally, as the yoke is approached to the HTS the flux variation of the HTS in 77 K is negligible compare to the flux variation of the HTS in the room temperature. Therefore, in superconductivity state the pinned fluxes in the HTS samples remain approximately constant and the HTS acts as a ‘magnetic isolator’. This specification can be used to simulate the behavior of field-cooled HTS by the FEM software.

Ghodsi, M.; Ueno, T.; Teshima, H.; Hirano, H.; Higuchi, T.

2006-10-01

92

Cable Bundle Wire Derating  

NASA Technical Reports Server (NTRS)

The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: 3.7 amps per wire, bundle of 15 or more wires, 70 C environment, and vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.

Lundquist, Ray A.; Leidecker, Henning

1998-01-01

93

Cable Bundle Wire Derating  

NASA Technical Reports Server (NTRS)

The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: (1) 3.7 amps per wire; (2) bundle of 15 or more wires; (3) 70 C environment: and (4) vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.

Lundquist, Ray A.; Leidecker, Henning

1998-01-01

94

Intermetallic compound formation at Cu-Al wire bond interface  

NASA Astrophysics Data System (ADS)

Intermetallic compound (IMC) formation and evolution at Cu-Al wire bond interface were studied using focused ion beam /scanning electron microscopy, transmission electron microscopy (TEM)/energy dispersive x-ray spectroscopy (EDS), nano beam electron diffraction (NBED) and structure factor (SF) calculation. It was found that discrete IMC patches were formed at the Cu/Al interface in as-packaged state and they grew toward Al pad after high temperature storage (HTS) environment at 150 °C. TEM/EDS and NBED results combined with SF calculation revealed the evidence of metastable ?'-CuAl2 IMC phase (tetragonal, space group: I4¯m2, a = 0.404 nm, c = 0.580 nm) formed at Cu/Al interfaces in both of the as-packaged and the post-HTS samples. Two feasible mechanisms for the formation of the metastable ?'-CuAl2 phase are discussed based on (1) non-equilibrium cooling of wire bond that is attributed to highly short bonding process time and (2) the epitaxial relationships between Cu and ?'-CuAl2, which can minimize lattice mismatch for ?'-CuAl2 to grow on Cu.

Bae, In-Tae; Young Jung, Dae; Chen, William T.; Du, Yong

2012-12-01

95

Intermetallic compound formation at Cu-Al wire bond interface  

SciTech Connect

Intermetallic compound (IMC) formation and evolution at Cu-Al wire bond interface were studied using focused ion beam /scanning electron microscopy, transmission electron microscopy (TEM)/energy dispersive x-ray spectroscopy (EDS), nano beam electron diffraction (NBED) and structure factor (SF) calculation. It was found that discrete IMC patches were formed at the Cu/Al interface in as-packaged state and they grew toward Al pad after high temperature storage (HTS) environment at 150 Degree-Sign C. TEM/EDS and NBED results combined with SF calculation revealed the evidence of metastable {theta} Prime -CuAl{sub 2} IMC phase (tetragonal, space group: I4m2, a = 0.404 nm, c= 0.580 nm) formed at Cu/Al interfaces in both of the as-packaged and the post-HTS samples. Two feasible mechanisms for the formation of the metastable {theta} Prime -CuAl{sub 2} phase are discussed based on (1) non-equilibrium cooling of wire bond that is attributed to highly short bonding process time and (2) the epitaxial relationships between Cu and {theta} Prime -CuAl{sub 2}, which can minimize lattice mismatch for {theta} Prime -CuAl{sub 2} to grow on Cu.

Bae, In-Tae; Young Jung, Dae [Small Scale Systems Integration and Packaging Center, State University of New York at Binghamton, Binghamton, New York 13902 (United States); Chen, William T.; Du Yong [Advanced Semiconductor Engineering Inc., 1255 E Arques Ave, Sunnyvale, California 94085 (United States)

2012-12-15

96

Large Wire Strain Gauges  

NASA Technical Reports Server (NTRS)

Wires yield data on average strains over distances ranging from inches to many feet. Long constantan wires used to measure average strains over distances characteristic of vehicles or buildings. Connected in bridge circuit, wires measure strain accurately within 1 percent, and linearly, within 0.1 percent. Wires stretch as much as 0.15 percent and still return to zero residual strain after release.

Bryner, B. D.

1987-01-01

97

High voltage insulation of bushing for HTS power equipment  

NASA Astrophysics Data System (ADS)

For the operation of high temperature superconducting (HTS) power equipments, it is necessary to develop insulating materials and high voltage (HV) insulation technology at cryogenic temperature of bushing. Liquid nitrogen (LN2) is an attractive dielectric liquid. Also, the polymer insulating materials are expected to be used as solid materials such as glass fiber reinforced plastic (GFRP), polytetra-fluoroethylene (PTFE, Teflon), Silicon (Si) rubber, aromatic polyamide (Nomex), EPDM/Silicon alloy compound (EPDM/Si). In this paper, the surface flashover characteristics of various insulating materials in LN2 are studied. These results are studied at both AC and impulse voltage under a non-uniform field. The use of GFRP and Teflon as insulation body for HTS bushing should be much desirable. Especially, GFRP is excellent material not only surface flashover characteristics but also mechanical characteristics at cryogenic temperature. The surface flashover is most serious problem for the shed design in LN2 and operation of superconducting equipments.

Kim, Woo-Jin; Choi, Jae-Hyeong; Kim, Sang-Hyun

2012-12-01

98

Characteristics of HTS tube depending on heat-treatment conditions  

NASA Astrophysics Data System (ADS)

Bi-2212 HTS tube was fabricated by centrifugal forming process (CFP). As a variation of melt casting process (MCP) or centrifugal casting technique, the CFP is a flexible method for manufacturing Bi-2212 bulk tubes and has been optimized to achieve smooth surface and uniform thickness. At this process, the slurry was prepared in the mixing ratio of 10:1 of Bi-2212 powder and binder. It was initially charged into the rotating mold at the speed of 300-450 rpm. Heat-treatment was performed at the temperature range 870-890°C in air for partial melting. The HTS tube fabricated by CFP at 890°C at the rotating speed of 450 rpm was highly densified and the plate-like grains with more than 20 ?m in diameter were well developed along the rotating axis. The measured Tc and Jc at 10 K were around 85 K and 3000 A/cm 2, respectively.

Park, Yong-Min; Jang, Gun-Eik

2001-03-01

99

Homogeneous performance and strain tolerance of long Bi-2223 HTS conductors under hoop stress  

NASA Astrophysics Data System (ADS)

Two types of high-strength industrial Bi-2223 conductor, one laminated by copper alloy and the other laminated by stainless steel, have been tested to examine the effect of hoop stress on the transport property. The specimens (˜2 m long) were prepared by winding one layer around a GFRP mandrel and the measurements were made in a liquid helium bath with the hoop stress calculated from the BJR product applied by external magnetic field. A careful measurement wire configuration was necessary to cancel the noise pick-up from the environment for more accurate determination of Ic and n-value. We show for the first time that both conductors showed homogeneous voltage-current characteristics over a long length and degradations with hoop stress occurred uniformly, which is crucial information for the development of HTS magnet technology. The onset of degradation occurred at 200 MPa and 220 MPa, with additional bending stress present from the winding diameter of 108 mm, for copper alloy laminated and stainless steel laminated conductors, respectively. After considering the effect of bending strain, our result agrees well with the previously measured data.

Miyoshi, Y.; Kitaguchi, H.; Chaud, X.; Debray, F.; Nishijima, G.; Tsuchiya, Y.

2014-02-01

100

Slide the wire  

NSDL National Science Digital Library

The animation shows a top view of four wires in a conducting loop and a galvanometer. Determine the direction of the magnetic field, Bz(x), passing through the wires at various postions by click-dragging the black wire back and forth and observing the galvanometer reading.

Wolfgang Christian

101

QRNT: A primary thermometer based on an HTS SQUID  

NASA Astrophysics Data System (ADS)

We propose a novel form of cryogenic primary thermometer based on flux quantisation in a HTS superconducting ring, interrupted by a Josephson junction which we call the Quantum Roulette Noise Thermometer (QRNT). Unlike other superconductivity-based noise thermometers this device is essentially dissipationless, requires no input or output connections and may be remotely interrogated. The QRNT has the potential to provide high accuracy with short measuring times.

Gallop, John; Hao, Ling; Reed, Richard

1997-08-01

102

HTS coils for the Navy's superconducting homopolar motor\\/generator  

Microsoft Academic Search

We report here on the development of HTS coils at Intermagnetics for the Navy's homopolar motor\\/generator program. Two coil sizes were used. A series of small test coils (14.0 cm i.d.×15.0 cm o.d.×1.4 cm long) were employed to evaluate various conductor winding, insulation and epoxy impregnation issues. Based upon the results of these test coils, the larger coil modules (19.37

D. W. Hazelton; M. T. Gardner; J. A. Rice; M. S. Walker; C. M. Trautwein; P. Haldar; D. U. Gubser; M. Superczynski; D. Waltman

1997-01-01

103

Application of HTS technology to cardiac dysrhythmia detection  

SciTech Connect

This paper discusses the conceptual design considerations and challenges for development of a contactless, mobile, single channel biomagnetic sensor system based on High-Temperature Superconductor (HTS) Superconducting Quantum Interference Devices (SQUIDs) and employing the Three-SQUID Gradiometer (TSG) concept. Operating in magnetically unshielded environments, as are encountered in many medical scenarios, this instrument class would monitor cardiac electrical activity with minimal patient preparation and intrusiveness, and would notionally be coupled with a clinically adaptive human-system interface (HSI).

Sobel, A.L. [Sandia National Labs., Albuquerque, NM (United States); Avrin, W.F. [Quantum Magnetics, Inc., San Diego, CA (United States)

1994-12-01

104

Present status and future trends of R&D for HTS rotational machines in Japan  

NASA Astrophysics Data System (ADS)

Various HTS rotating machines, from multiple MW class to several 10 kW class, are being developed in Japan. R&D statuses of those machines are reviewed. Design studies of various types of HTS wind power generators are also conducted in Japan and their merits and demerits are discussed. Based on the present R&D statuses, future technical trends of HTS machines are discussed.

Tsukamoto, Osami

2014-09-01

105

Cryogenic system with the sub-cooled liquid nitrogen for cooling HTS power cable  

Microsoft Academic Search

A 10m long, three-phase AC high-temperature superconducting (HTS) power cable had been fabricated and tested in China August 2003. The sub-cooled liquid nitrogen (LN2) was used to cool the HTS cable. The sub-cooled LN2 circulation was built by means of a centrifugal pump through a heat exchanger in the sub-cooler, the three-phase HTS cable cryostats and a LN2 gas–liquid separator.

Y. F. Fan; L. H. Gong; X. D. Xu; L. F. Li; L. Zhang; L. Y. Xiao

2005-01-01

106

Synchronous Generator with HTS-2G field coils for Windmills with output power 1 MW  

NASA Astrophysics Data System (ADS)

Nowadays synchronous generators for wind-mills are developed worldwide. The cost of the generator is determined by its size and weight. In this deal the implementation of HTS-2G generators is very perspective. The application of HTS 2G field coils in the rotor allows to reduce the size of the generator is 1.75 times. In this work the design 1 MW HTS-2G generator is considered. The designed 1 MW HTS-2G generator has the following parameters: rotor diameter 800 mm, active length 400 mm, phase voltage 690V, rotor speed 600 min-1 rotor field coils with HTS-2G tapes. HTS-2G field coils located in the rotating cryostat and cooled by liquid nitrogen. The simulation and optimization of HTS-2G field coils geometry allowed to increase feed DC current up to 50A. Copper stator windings are water cooled. Magnetic and electrical losses in 1 MW HTS-2G generator do not exceed 1.6% of the nominal output power. In the construction of HTS-2G generator the wave multiplier with ratio 1:40 is used. The latter allows to reduce the total mass of HTS-2G generator down to 1.5 tons. The small-scale model of HTS-2G generator with output power 50 kW was designed, manufactured and tested. The test results showed good agreement with calculation results. The manufacturing of 1 MW HTS-2G generator is planned in 2014. This work is done under support of Rosatom within the frames of Russian Project "Superconducting Industry".

Kovalev, K.; Kovalev, L.; Poltavets, V.; Samsonovich, S.; Ilyasov, R.; Levin, A.; Surin, M.

2014-05-01

107

Bi2212 HTS Conical Tubes Prepared by the Diffusion Process for Current Lead Application  

Microsoft Academic Search

Bi2212 HTS conical tubular conductors have been prepared by the diffusion process for current lead application. The Bi2212 HTS layers are synthesized through the diffusion reaction between a Sr-Ca-Cu oxide substrate and a Bi-Cu oxide coating with Ag addition. The HTS diffusion layers about 150 micrometer in thickness are formed around both outside and inside of the conical tubes 37\\/29

Y. Yamada; M. Watanabe; J. Ohkubo; K. Tachikawa; H. Tamura; A. Iwamoto; T. Mito

2006-01-01

108

Performance test of Bi2212 HTS current leads prepared by the diffusion process  

Microsoft Academic Search

Bi-2212 HTS bulk conductors have been prepared by the two components diffusion process for current lead application. The Bi-2212 HTS layer is synthesized through a diffusion reaction between a Sr-Ca-Sr oxide substrate and a Bi-Cu oxide coating with Ag addition. The HTS diffusion layer about 150 ?m in thickness formed around the cylindrical tube 27\\/19 mm in outside\\/inside diameter and

Y. Yamada; O. Suzuki; A. Enomoto; K. Tachikawa; H. Tamura; A. Iwamoto; T. Mito

2002-01-01

109

Thin wire pointing method  

NASA Technical Reports Server (NTRS)

A method is described for forming sharp tips on thin wires, in particular phosphor bronze wires of diameters such as one-thousandth inch used to contact micron size Schottky barrier diodes, which enables close control of tip shape and which avoids the use of highly toxic solutions. The method includes dipping an end of a phosphor bronze wire into a dilute solution of sulfamic acid and applying a current through the wire to electrochemically etch it. The humidity in the room is controlled to a level of less than 50%, and the voltage applied between the wire and another electrode in the solutions is a half wave rectified voltage. The current through the wire is monitored, and the process is stopped when the current falls to a predetermined low level.

Green, G.; Mattauch, R. J. (inventors)

1983-01-01

110

Sintered wire annode  

DOEpatents

A plurality of high atomic number wires are sintered together to form a porous rod that is parted into porous disks which will be used as x-ray targets. A thermally conductive material is introduced into the pores of the rod, and when a stream of electrons impinges on the sintered wire target and generates x-rays, the heat generated by the impinging x-rays is removed by the thermally conductive material interspersed in the pores of the wires.

Falce, Louis R. (Surprise, AZ); Ives, R. Lawrence (Saratoga, CA)

2007-12-25

111

Wire-inhomogeneity detector  

DOEpatents

A device for uncovering imperfections in electrical conducting wire, particularly superconducting wire, by detecting variations in eddy currents. Eddy currents effect the magnetic field in a gap of an inductor, contained in a modified commercial ferrite core, through which the wire being tested is passed. A small increase or decrease in the amount of conductive material, such as copper, in a fixed cross section of wire will unbalance a bridge used to measure the impedance of the inductor, tripping a detector and sounding an alarm.

Gibson, G.H.; Smits, R.G.; Eberhard, P.H.

1982-08-31

112

Aspects on HTS applications in confined power grids  

NASA Astrophysics Data System (ADS)

In an increasing number of electric power grids the share of distributed energy generation is also increasing. The grids have to cope with a considerable change of power flow, which has an impact on the optimum topology of the grids and sub-grids (high-voltage, medium-voltage and low-voltage sub-grids) and the size of quasi-autonomous grid sections. Furthermore the stability of grids is influenced by its size. Thus special benefits of HTS applications in the power grid might become most visible in confined power grids.

Arndt, T.; Grundmann, J.; Kuhnert, A.; Kummeth, P.; Nick, W.; Oomen, M.; Schacherer, C.; Schmidt, W.

2014-12-01

113

Development of HTS current leads for 1 kWh\\/1 MW module type SMES system. I. Design study  

Microsoft Academic Search

We have been developing high-temperature superconducting (HTS) current leads for a 1 kWh\\/1 MW module-type SMEs. Each module of a module-type SMES requires a pair of current leads. Therefore, we employed bulk HTS in order to reduce the heat load of the current leads. It is important that HTS current leads for SMES be reliable. The HTS current leads described

M. Konno; K. Sakaki; T. Uede; A. Tomioka; T. Bohno; S. Nose; T. Imayasho; H. Hayashi; K. Tsutsumi; F. Irie

1997-01-01

114

Superconductivity for Electric Systems Program Review LANL Contributions to GE HTS Generator  

E-print Network

Superconductivity for Electric Systems Program Review LANL Contributions to GE HTS Generator-section · Develop a heat generation profile => thermal analysis #12;Superconductivity for Electric Systems Program;Superconductivity for Electric Systems Program Review Objective was successful demonstration of 100 MVA HTS

115

The Design of a Lightweight HTS Synchronous Generator Cooled by Subcooled Liquid Nitrogen  

Microsoft Academic Search

A final design of a dasiacorelesspsila 100 kW HTS synchronous generator, to be built at the University of Southampton is under way. The new generator will use the same conventional 2-pole, 3 phase stator used by for the dasiairon coredpsila generator. The new HTS rotor has no central core and the rotor winding is built with 15 double pancake coils.

Wendell O. S. Bailey; Maitham Al-Mosawi; Yifeng Yang; Kevin Goddard; Carlo Beduz

2009-01-01

116

Weight and power considerations for the design of a cryogenically cooled HTS electronic system  

Microsoft Academic Search

Much progress has been reported on the fabrication of high temperature superconducting (HTS) electronic devices, circuits and systems. In some of these reports, comparisons have been made between the electrical behavior of HTS components and their “equivalent” semiconductor counterparts. Unfortunately, in almost all cases, the comparisons have been made at the device or circuit level. In an operational system, the

M Nisenoff

1996-01-01

117

Development of Robust HTS-SQUID for Non-destructive Inspection System in Unshielded Environment  

NASA Astrophysics Data System (ADS)

Cross-shaped YBa2Cu3O7-x (YBCO) film was overlapped on directly-coupled multi-pickup-coil HTS-dc-SQUID magnetometer in flip-chip configuration as a superconducting shield, and the characterestics of the SQUID were examined in DC and AC magnetic fields. We created slots in the YBCO film and pickup-coil of HTS-SQUID magnetometer for suppression of flux trapping. In low magnetic field environment, we measured the characteristics of the SQUID without and with HTS film. The most of the parameters were same with and without the HTS films, while S1/2phi with the HTS film was a bit smaller than that of the bare SQUID. In the DC field, Ic of the HTS-SQUID covered with the HTS film did not change until a DC field over 140 ?T was applied to the SQUID, while the bare SQUID's Ic decreased with the increase of the applied DC field. In the AC fields at 10 MHz, the SQUID with the HTS film showed degradation of the parameters such as Vpp and S12phi at lower field amplitude than the bare SQUID.

Yoshida, K.; Kage, T.; Suzuki, T.; Hatsukade, Y.; Tanaka, S.

2014-05-01

118

THE UTILIZATION OF THE NTP-HTS DATA IN CHEMICAL TOXICITY MODELING  

EPA Science Inventory

To explore efficient approaches to assessing the toxicity of environmental chemicals, the NIEHS National Toxicology Program (NTP) recently initiated a High Throughput Screening (HTS) Project. To date, HTS results for a set of 1,408 compounds tested in 6 cell viability assays have...

119

Failure analysis of high temperature superheater tube (HTS) of a pulverized coal-fired power station  

Microsoft Academic Search

This paper presents the failure investigation of high temperature superheater (HTS) tubes. Samples were collected from one of the coal fired power plants in Malaysia, namely, Stesen Janakuasa Sultan Azlan Shah, Manjung (Manjung Power Station). After eight years of non-continuous services of three boilers, welded support-clips were completely separated (detached) from (HTS) tubes, which caused the wall thinning. Collected failed

Ahmad Kamal Kadir

2011-01-01

120

Model of HTS three-phase saturated core fault current limiter  

Microsoft Academic Search

A small (several hundred watts) model of a three phase saturated core HTS fault current limiter (FCL) was developed and tested. Iron yokes of all three phases were saturated by a single DC HTS coil. The coil comprised a 60 turns single pancake (ID 135 mm), wound after heat treatment from Bi-2223 multifilamentary tape in Ag matrix. The critical current

V. Keilin; I. Kovalev; S. Kruglov; V. Stepanov; I. Shugaev; V. Shcherbakov; I. Akimov; D. Rakov; A. Shikov

2000-01-01

121

Identification of Insulation Defects in Cryogenic Dielectric Materials for the HTS Power Applications  

Microsoft Academic Search

Recently, various high temperature superconducting (HTS) power applications have been developed and prepared for field tests and commercial applications. Comparing to conventional power applications, it could offer several advantages such as reduced size and weight, high efficiency, decreased losses, no oil, nonflammable and decrease of ${\\\\rm CO}{2}$ emissions. Besides overload operation is possible with no loss of lifetime. For HTS

I. J. Seo; Y. J. Lee; J. K. Seong; W. J. Shin; B. W. Lee; J. Y. Koo

2012-01-01

122

Inspection of fine wires simplified by capillary tube wire holder  

NASA Technical Reports Server (NTRS)

Capillary tube wire holder provides a mount for fine wires for photomicrographs. The holder is mounted in a stainless steel tube and cast in a transparent casting material. It protects and permits easy location of the wire.

Raphael, H. A.

1965-01-01

123

Vibration Characteristics in Magnetic Levitation Type Seismic Isolation Device Composed of Multiple HTS Bulks and Permanent Magnets  

Microsoft Academic Search

An HTS bulk field-cooled by a permanent magnet can levitate stably without any other control systems. The stable levitation can be realized by a specific characteristic of the HTS bulk that the HTS bulk returns to its original position by restoring force against horizontal displacement. We devised a magnetic levitation type seismic isolation device taking advantage of the specific characteristic

M. Tsuda; T. Kojima; T. Yagai; T. Hamajima

2007-01-01

124

Characteristic analysis of 154 kV HTS power cable under fault conditions using PSCAD/EMTDC  

NASA Astrophysics Data System (ADS)

This paper deals with the characteristic analysis of 154 kV HTS power cable system under fault conditions using PSCAD/EMTDC (Power System Computer Aided Design/Electromagnetic Transients including DC). Before applying the HTS power cable to the real utility, the system needs to be analyzed using certain simulation tools. The resistance of conventional power cables is not changed by fault current. But HTS power cable has some different properties. The impedance of superconductor is dramatically changed along with the current over the critical value, temperature, and magnetic field. PSCAD/EMTDC does not provide the HTS power cable model which includes the same electrical characteristics of real HTS power cable. In order to develop the EMTDC model component of 154 kV class HTS power cable, the authors have manufactured a 1/58 HTS model power cable and experimented under several types of fault conditions. The measured characteristics of the model cable, resistance and temperature variation, were used to develop the HTS power cable model component in EMTDC. Using this model component, HTS power cable system was analyzed under the fault conditions. The simulation results of fault current, temperature and resistance variation of HTS power cable are described in detail, and how to apply the characteristics of HTS power cable in the simulation tool is also discussed in order to demonstrate the effectiveness of the proposed model component of 154 kV class HTS power cable.

Kim, J. G.; Lee, J.; Kim, J. H.; Kim, A. R.; Cho, J.; Sim, K. D.; Kim, S.; Park, M.; Yu, I. K.; Lee, J. K.

2009-10-01

125

The Dynamic Characteristics of 3-D Superconducting Actuator Using the Magnetized HTS Bulk by Sandwiched Electromagnets  

NASA Astrophysics Data System (ADS)

The electric device applications of a high temperature superconducting (HTS) bulk, having stable levitation and suspension properties due to their strong flux pinning force, have been proposed and developed. We have been investigating the three-dimensional (3-D) superconducting actuator using HTS bulk to develop a non-contact transportation device. In our previous works, the overshooting of the HTS bulk mover magnetized by 2-D arranged electromagnets were observed. Therefore, the new magnetization method using sandwiched electromagnets was purposed in order to solve the overshooting problems of HTS bulk mover. In this paper, the dynamic stabilities on the rotating and horizontal moving of the HTS bulk mover magnetized by sandwiched electromagnets was investigated experimentally, and the maximum moving displacements and convergence times during the overshooting state were reduced by proposed magnetization method with small magnetizing current.

Nakano, H.; Kim, S. B.; Ozasa, S.; Sawae, M.

126

The thermal relay design to improve power system security for the HTS cables in Icheon substation  

NASA Astrophysics Data System (ADS)

This paper proposes a model for thermal protection relay for the high temperature superconducting (HTS) cables and thermal protection scheme in Icheon substation in Korea. The thermal protection is one of the most important factors to guarantee the reliability of the HTS cable as well as power system security. The superconductivity of the HTS cables, which can be guaranteed by the liquid nitrogen near 70 K, can be threatened by the large fault current. To avoid the overheating in HTS cable and to secure the power system operation with the HTS cable, the thermal protection relay should be considered. To find the optimal thermal-protection scheme, the model for the superconducting power system has been achieved in Icheon substation and the thermal protection scheme has been verified through PSCAD/EMTDC simulation.

Lee, Hansang; Yang, Byeong-Mo; Jang, Gilsoo

2013-11-01

127

Wire Array Photovoltaics  

NASA Astrophysics Data System (ADS)

Over the past five years, the cost of solar panels has dropped drastically and, in concert, the number of installed modules has risen exponentially. However, solar electricity is still more than twice as expensive as electricity from a natural gas plant. Fortunately, wire array solar cells have emerged as a promising technology for further lowering the cost of solar. Si wire array solar cells are formed with a unique, low cost growth method and use 100 times less material than conventional Si cells. The wires can be embedded in a transparent, flexible polymer to create a free-standing array that can be rolled up for easy installation in a variety of form factors. Furthermore, by incorporating multijunctions into the wire morphology, higher efficiencies can be achieved while taking advantage of the unique defect relaxation pathways afforded by the 3D wire geometry. The work in this thesis shepherded Si wires from undoped arrays to flexible, functional large area devices and laid the groundwork for multijunction wire array cells. Fabrication techniques were developed to turn intrinsic Si wires into full p-n junctions and the wires were passivated with a-Si:H and a-SiNx:H. Single wire devices yielded open circuit voltages of 600 mV and efficiencies of 9%. The arrays were then embedded in a polymer and contacted with a transparent, flexible, Ni nanoparticle and Ag nanowire top contact. The contact connected >99% of the wires in parallel and yielded flexible, substrate free solar cells featuring hundreds of thousands of wires. Building on the success of the Si wire arrays, GaP was epitaxially grown on the material to create heterostructures for photoelectrochemistry. These cells were limited by low absorption in the GaP due to its indirect bandgap, and poor current collection due to a diffusion length of only 80 nm. However, GaAsP on SiGe offers a superior combination of materials, and wire architectures based on these semiconductors were investigated for multijunction arrays. These devices offer potential efficiencies of 34%, as demonstrated through an analytical model and optoelectronic simulations. SiGe and Ge wires were fabricated via chemical-vapor deposition and reactive ion etching. GaAs was then grown on these substrates at the National Renewable Energy Lab and yielded ns lifetime components, as required for achieving high efficiency devices.

Turner-Evans, Dan

128

Novel trimming technique for tunable HTS microstrip filters  

NASA Astrophysics Data System (ADS)

We have developed a method using additional electric pads for trimming tunable high-temperature superconducting (HTS) microstrip filters. These filters are generally tuned by adjusting the gap between a dielectric floating plate above the filter. When the floating plate approached the filter, the center frequency was shifted to a lower frequency. However, the insertion loss increases due to variation in the external quality factors varying from the design parameter. The external quality factors are usually controlled by adjusting the length of the input/output (I/O) coupled-line elements and the gap between the elements and the resonator. In our method, additional electric pads are distributed at the open-end of the I/O coupled-line elements of a 3-pole hairpin bandpass filter to enable adjustment of the external quality factors so as to reduce insertion loss. The electric pads consist of line-and-space patterns. They are eclectically connected to the coupled-line elements to adjust the line length and gap width and thereby control the external quality factors. An electromagnetic simulator was used for the design and analysis. The simulation results showed that the additional electric pads are effective in improving the insertion loss of the HTS bandpass filter after tuning.

Sekiya, N.; Nakagawa, Y.; Saito, A.; Ohshima, S.

2008-09-01

129

5 MJ flywheel based on bulk HTS magnetic suspension  

NASA Astrophysics Data System (ADS)

Nowadays the flywheel energy storage systems (FES) are developed intensively as uninterruptible power supply (UPS) devices for on-land and transport (especially airborne) applications worldwide. This work is devoted to the FES with magnetic suspension on the base of bulk HTS YBCO elements and permanent magnets. The developed FES is intended to be used as UPS in Russian atomic industry in case of an emergency. For the successful design of the FES the following questions should be solved: design of the motor/generator, design of the rotor (flywheel), design of the bearing system, design of the control system and system of power load matching, design of the cooling system. The developed small-scale FES with the stored energy 0.5 MJ was used to solve these basic questions. The elaborated FES consists of the synchronous electric machine with permanent magnets, the solid flywheel with axial magnetic suspension on the base of YBCO bulks and permanent magnets, the system of control and power load matching, and the system of liquid nitrogen cooling. The results of theoretical modeling of different schematics of magnetic suspension and experimental investigations of the constructed FES are presented. The design of the future full-scale FES with the stored energy ~5 MJ and output power up to 100 kW is described. The test results of the flywheel rotor and HTS magnetic suspension of 5 MJ FES are presented. This work is done under support of Rosatom within the frames of Russian Project "Superconducting Industry"

Poltavets, V.; Kovalev, K.; Ilyasov, R.; Glazunov, A.; Maevsky, V.; Verzbitsky, L.; Akhmadyshev, V.; Shikov, A.

2014-05-01

130

Restoration and testing of an HTS fault current controller  

SciTech Connect

A three-phase, 1200 A, 12.5 kV fault current controller using three HTS 4 mH coils, was built by industry and tested in 1999 at the Center Substation of Southern California Edison in Norwalk, CA. During the testing, it appeared that each of the three single-phase units had experienced a voltage breakdown, one externally and two internally. Los Alamos National Laboratory (LANL) was asked by DOE to restore the operation of the fault current controller provided the HTS coils had not been damaged during the initial substation tests. When the internally-failed coil vacuum vessels were opened it became evident that in these two vessels, a flashover had occurred at the high voltage bus section leading to the terminals of the superconducting coil. An investigation into the failure mechanism resulted in six possible causes for the flashover. Based on these causes, the high voltage bus was completely redesigned. Single-phase tests were successfully performed on the modified unit at a 13.7 kV LANL substation. This paper presents the postulated voltage flashover failure mechanisms, the new high voltage bus design which mitigates the failure mechanisms, the sequence of tests used to validate the new design, and finally, the results of variable load and short-circuit tests with the single-phase unit operating on the LANL 13.7 kV substation.

Waynert, J. A. (Joseph A.); Boenig, H. (Heinrich E.); Mielke, C. H. (Charles H.); Willis, J. O. (Jeffrey O.); Burley, B. L. (Burt L.)

2002-01-01

131

Sub-Micron Long HTS Ho Electron Mixers  

NASA Technical Reports Server (NTRS)

The hot-electron bolometer mixer made from a high-T, superconductor (HTS) was introduced recently as an alternative to a Schottky mixer at THz frequencies. The performance of the mixer depends on the total thermal conductance for heat removal from the phonon sub-system due to either length-dependent phonon diffusion or phonon escape to the substrate. We have measured both the length and temperature dependencies of the IF bandwidth of the mixers fabricated from 25-35 mn thick YBCO films on MgO and sapphire substrates. The films were grown by a laser deposition technique and electron-beam lithography was used to define bridge lengths down to 50 nm. Mixer measurements were done using signal frequencies in the range of 1-100 GHz. For 50 nm and 400 nm long devices on MgO, the 3-dB bandwidth was about 100 MHz. At temperatures below 60 K, the hot-electron plateau was clearly seen starting around 2-3 GHz. At temperatures above 70 K, the flux-flow effects begin to dominate and the IF bandwidth increases to 1-8 GHz, while the conversion efficiency drops by several dB. This temperature dependence of the IF bandwidth can account for previously reported unexpectedly high bandwidth of HTS mixers.

Harnack, 0.; Karasik, B. S.; McGrath, W. R.; Kleinsasser, A. W.; Barner, J. B.

2000-01-01

132

HTS Magnets for Advanced Magnetoplasma Space Propulsion Applications  

SciTech Connect

Plasma rockets are being considered for both Earth-orbit and interplanetary missions because their extremely high exhaust velocity and ability to modulate thrust allow very efficient use of propellant mass. In such rockets, a hydrogen or helium plasma is RF-heated and confined by axial magnetic fields produced by coils around the plasma chamber. HTS coils cooled by the propellant are desirable to increase the energy efficiency of the system. We describe a set of prototype high-temperature superconducting (HTS) coils that are being considered for the VASIMR ( Variable Specific Impulse Magnetoplasma Rocket) thruster proposed for testing on the Radiation Technology Demonstration (RTD) satellite. Since this satellite will be launched by the Space Shuttle, for safety reasons liquid helium will be used as propellant and coolant. The coils must be designed to operate in the space environment at field levels of 1 T. This generates a unique set of requirements. Details of the overall winding geometry and current density, as well as the challenging thermal control aspects associated with a compact, minimum weight design will be discussed.

Carte, M.D.; Chang-Diaz, F.R. Squire, J.P.; Schwenterly, S.W.

1999-07-12

133

Wire Weight with Housing  

USGS Multimedia Gallery

Wire weight is lowered to water surface to measure stage at a site. Levels are made to the wire weights elevation from known benchmarks to ensure correct readings. In the background there is housing protected with dikes along the Missouri River in Mandan, ND....

134

Imagination Visualized in Wire.  

ERIC Educational Resources Information Center

Describes an art lesson achieved with a Very Special Artist (VSA) in residence for sixth- and seventh-grade students in which they created wire sculptures. Discusses how the VSA taught the students. Includes a list of art materials and characteristics of wire. (CMK)

Skophammer, Karen

2003-01-01

135

Commercial and Industrial Wiring.  

ERIC Educational Resources Information Center

This module is the third in a series of three wiring publications, includes additional technical knowledge and applications required for job entry in the commercial and industrial wiring trade. The module contains 15 instructional units that cover the following topics: blueprint reading and load calculations; tools and equipment; service;…

Kaltwasser, Stan; Flowers, Gary

136

Analysis on heat loss characteristics of a 10 kV HTS power substation  

NASA Astrophysics Data System (ADS)

A 10 kV High Temperature Superconducting power substation (10 kV HTS substation), supported by Chinese State 863 projects, was developed and has been running to supply power for several factories for more than two years at an industrial park of Baiyin, Gansu province in Northwest China. The system of the 10 kV HTS substation compositions, including a HTS cable, a HTS transformer, a SFCL, and a SMES, are introduced. The SMES works at liquid helium temperature and the other three apparatus operates under liquid nitrogen condition. There are mainly four types of heat losses existing in each HTS apparatus of the 10 kV HTS substation, including AC loss, Joule heat loss, conductive heat, and leak-in heat from cryostat. A small quantity of AC loss still exists due to the harmonic component of the current when it carries DC for HTS apparatus. The principle and basis for analysis of the heat losses are introduced and the total heat loss of each apparatus are calculated or estimated, which agree well with the test result. The analysis and result presented are of importance for the design of the refrigeration system.

Teng, Yuping; Dai, Shaotao; Song, Naihao; Zhang, Jingye; Gao, Zhiyuan; Zhu, Zhiqin; Zhou, Weiwei; Wei, Zhourong; Lin, Liangzhen; Xiao, Liye

2014-09-01

137

Next Generation Wiring  

NASA Technical Reports Server (NTRS)

Wiring is a major operational component on aerospace hardware that accounts for substantial weight and volumetric space. Over time wire insulation can age and fail, often leading to catastrophic events such as system failure or fire. The next generation of wiring must be reliable and sustainable over long periods of time. These features will be achieved by the development of a wire insulation capable of autonomous self-healing that mitigates failure before it reaches a catastrophic level. In order to develop a self-healing insulation material, three steps must occur. First, methods of bonding similar materials must be developed that are capable of being initiated autonomously. This process will lead to the development of a manual repair system for polyimide wire insulation. Second, ways to initiate these bonding methods that lead to materials that are similar to the primary insulation must be developed. Finally, steps one and two must be integrated to produce a material that has no residues from the process that degrades the insulating properties of the final repaired insulation. The self-healing technology, teamed with the ability to identify and locate damage, will greatly improve reliability and safety of electrical wiring of critical systems. This paper will address these topics, discuss the results of preliminary testing, and remaining development issues related to self-healing wire insulation.

Medelius, Petro; Jolley, Scott; Fitzpatrick, Lilliana; Vinje, Rubiela; Williams, Martha; Clayton, LaNetra; Roberson, Luke; Smith, Trent; Santiago-Maldonado, Edgardo

2007-01-01

138

Orbiter Kapton wire operational requirements and experience  

NASA Technical Reports Server (NTRS)

The agenda of this presentation includes the Orbiter wire selection requirements, the Orbiter wire usage, fabrication and test requirements, typical wiring installations, Kapton wire experience, NASA Kapton wire testing, summary, and backup data.

Peterson, R. V.

1994-01-01

139

LimeWire  

NSDL National Science Digital Library

LimeWire, version 2.1.1, is a software package that enables individuals to search for and share computer files with anyone on the Internet. This software lets you log on to the Gnutella peer-to-peer network and contains a list of MP3's, digital home movies, documents, and other software. Furthermore, it allows you to chat with other LimeWire users. This latest version incorporates several performance improvements, including enhanced tools for handling downloads from slow servers and bad connections. LimeWire is written in Java and will run on Windows, Macintosh, Linux, Sun, and other computing platforms.

140

Design, Construction and Test of Cryogen-Free HTS Coil Structure  

SciTech Connect

This paper will describe design, construction and test results of a cryo-mechanical structure to study coils made with the second generation High Temperature Superconductor (HTS) for the Facility for Rare Isotope Beams (FRIB). A magnet comprised of HTS coils mounted in a vacuum vessel and conduction-cooled with Gifford-McMahon cycle cryocoolers is used to develop and refine design and construction techniques. The study of these techniques and their effect on operations provides a better understanding of the use of cryogen free magnets in future accelerator projects. A cryogen-free, superconducting HTS magnet possesses certain operational advantages over cryogenically cooled, low temperature superconducting magnets.

Hocker, H.; Anerella, M.; Gupta, R.; Plate, S.; Sampson, W.; Schmalzle, J.; Shiroyanagi, Y.

2011-03-28

141

Study of HTS Insert Coils for High Field Solenoids  

SciTech Connect

Fermilab is currently working on the development of high field magnet systems for ionization cooling of muon beams. The use of high temperature superconducting materials (HTS) is being considered for these solenoids using Helium refrigeration. Several studies have been performed on insert coils made of BSCCO-2223 tapes and second generation (2G) YBCO coated conductors, which are tested at various temperatures and at external fields of up to 14 T. Critical current (I{sub c}) measurements of YBCO short samples are presented as a function of bending stress, magnetic field and field orientation with respect to the sample surface. An analytical fit of critical current data as a function of field and field orientation is also presented. Results from several single-layer and double-layer pancake coils are also discussed.

Lombardo, Vito; /Fermilab

2009-09-01

142

Development of magnetic drug delivery system using HTS bulk magnet  

NASA Astrophysics Data System (ADS)

Magnetic drug delivery system (MDDS) is the method which the magnetic seeded drug is injected into a blood vessel and then controlled and accumulated by a magnet located outside of the human body. A high accumulation efficiency of the drug to a local diseased part and reduction in side-effects to normal organs are expected by using MDDS. The most important element in MDDS is a magnetic field generator. The high temperature superconducting (HTS) bulk magnet which can generate high magnetic field and magnetic field gradient extending to a point distant from the magnet in several ten millimeters is necessary to achieve the MDDS. In this study, the computer simulation and model experiment were conducted in order to confirm the applicability of MDDS to ovary of the cow body.

Terada, T.; Fukui, S.; Mishima, F.; Akiyama, Y.; Izumi, Y.; Nishijima, S.

2008-09-01

143

Wire polarizers for microwave antennas  

Microsoft Academic Search

The paper deals with free space polarizers that are essentially planar, consisting of dielectric sheets and grids of parallel conducting wires. Network models are used in the analysis of wire grid structures. An expression for the equivalent wire grid reactance is studied, including the general case of obliquely incident plane waves. The influence of dielectric interfaces close to the wire

L. G. Josefsson

1978-01-01

144

30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2013 CFR

...Resources 1 2013-07-01 2013-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 75.1003 Insulation of trolley wires, trolley feeder wires and bare signal...

2013-07-01

145

30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2013 CFR

...Resources 1 2013-07-01 2013-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare signal...

2013-07-01

146

30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2014 CFR

...Resources 1 2014-07-01 2014-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare signal...

2014-07-01

147

30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2010 CFR

...Resources 1 2010-07-01 2010-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare signal...

2010-07-01

148

30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2012 CFR

...Resources 1 2012-07-01 2012-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 75.1003 Insulation of trolley wires, trolley feeder wires and bare signal...

2012-07-01

149

30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2011 CFR

...Resources 1 2011-07-01 2011-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 75.1003 Insulation of trolley wires, trolley feeder wires and bare signal...

2011-07-01

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30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2014 CFR

...Resources 1 2014-07-01 2014-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 75.1003 Insulation of trolley wires, trolley feeder wires and bare signal...

2014-07-01

151

30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2011 CFR

...Resources 1 2011-07-01 2011-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare signal...

2011-07-01

152

30 CFR 77.1802 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2012 CFR

...Resources 1 2012-07-01 2012-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 77.1802 Insulation of trolley wires, trolley feeder wires and bare signal...

2012-07-01

153

30 CFR 75.1003 - Insulation of trolley wires, trolley feeder wires and bare signal wires; guarding of trolley...  

Code of Federal Regulations, 2010 CFR

...Resources 1 2010-07-01 2010-07-01 false Insulation of trolley wires, trolley feeder wires and bare signal wires...MINES Trolley Wires and Trolley Feeder Wires § 75.1003 Insulation of trolley wires, trolley feeder wires and bare signal...

2010-07-01

154

Loss measurement and analysis for the prototype generator with HTS stator and permanent magnet rotor  

NASA Astrophysics Data System (ADS)

A prototype HTS synchronous generator with a permanent magnet rotor and HTS armature windings was developed. The rated armature frequency is 10 Hz. The cryogenic Dewar is tightly surrounded outside the iron core. Both HTS coils and the iron core were cooled by using conduction cooling method. During the process of no-load running, the no-load loss power data were obtained through the torque measurement. The temperature evolution characteristics of the stator was measured by PT-100 temperature sensors. These results show that the no-load loss power at around 77 K are much larger than that at room temperature. The possible reason for the no-load loss increment is discussed. The ac loss power of one individual HTS coil used in this generator was also tested. Compared with the iron loss power, the ac loss power is rather small and could be neglected.

Song, Peng; Qu, Timing; Yu, Xiaoyu; Li, Longnian; Gu, Chen; Li, Xiaohang; Wang, Dewen; Hu, Boping; Chen, Duxing; Han, Zhenghe

2013-11-01

155

Abstract--Microdroplet systems can drastically reduce costs and increase throughput in high throughput screening (HTS)  

E-print Network

. Microdroplet-based HTS has the potential to reduce assay Manuscript received April 23, 2009. V. Trivedi, E University. A. Doshi and A. Basu are with the department of Electrical and Computer Engineering at Wayne

VandeVord, Pamela

156

Status of 275 kV REBCO HTS Cable Development in the NEDO Project  

NASA Astrophysics Data System (ADS)

A 275 kV 3 kA high temperature superconducting cable (HTS cable), which could be used as a backbone power line in the future, was developed in the NEDO project called M-PACC. One of the most important developments of a high voltage HTS cable was the high voltage insulation technology. A design guideline and a test specification that was necessary to design, product and demonstrate of a 275 kV, 3 kA HTS cable have been studied by obtaining the various experimental data such as AC withstand voltage, impulse withstand voltage, partial discharge inception stress, and the V-t characteristics of the insulation, on the basis of the Japan Electrical Standards (JEC) and the International Electrotechnical Commission (IEC). Moreover, the 275 kV, 3 kA HTS cable with a length of 30 m was demonstrated under a long-term voltage and current loading test.

Mukoyama, Shinichi; Yagi, Masashi; Okuma, Takeshi; Maruyama, Osamu; Shiohara, Yuu; Hayakawa, Naoki; Mizutani, Teruyoshi

157

Magnetic Forces Simulation of Bulk HTS over Permanent Magnetic Railway with Numerical Method  

NASA Astrophysics Data System (ADS)

Magnetic levitation forces of bulk high temperature superconductor (HTS) above two types permanent magnet railway (PMR) is simulated using finite element method (FEM). The models are formulated by H-formulation and resolving codes is developed using Finite Element Program Generator (FEPG). The E- J power law is used to describe the electrical field vs. current density nonlinear characteristic of HTS. The applied magnetic fields induced by the PMR are calculated by the standard analysis method with the equivalent surface current model. By the method, the calculation formulation of magnetic fields generated by Halbach PMR and symmetrical PMR is derived respectively. The simulation results show that the finite element dynamic mesh rebuilding problem of HTS magnetic levitation transportation system comprised of bulk HTS and PMR can be easily avoided by the methods.

Lu, Yiyun; Zhuang, Shujun

2012-10-01

158

HTS Bulk Pole-Field Magnets Motor With a Multiple Rotor Cooled by Liquid Nitrogen  

Microsoft Academic Search

High-Tc superconductor (HTS) rotating machine with melt-textured Gd-123 bulk pole-field magnets was assembled and tested. The axial gap type motor with neither brush\\/slip ring nor iron core was composed of a kind of multiple rotor, i.e., a twinned rotor. On each rotor disk, there are eight Gd-123 HTS bulk magnets. The bulk magnets were cooled down with circulating liquid nitrogen

Hirohisa Matsuzaki; Yousuke Kimura; Eisuke Morita; Hideaki Ogata; Tetsuya Ida; Mitsuru Izumi; Hidehiko Sugimoto; Motohiro Miki; Masahiro Kitano

2007-01-01

159

Status of HTS current leads for WENDELSTEIN 7-X and JT-60SA  

Microsoft Academic Search

The stellarator WENDELSTEIN 7-X (W7-X) and the satellite tokamak JT-60SA will use High Temperature Superconductor (HTS) current leads to reduce cryogenic load and operational cost. Forschungszentrum Karlsruhe is in charge of design, construction and test of these HTS current leads. For W7-X fourteen current leads with a nominal current of 14kA and a maximum current of 18.2kA are required that

W. H. Fietz; R. Heller; A. Kienzler; R. Lietzow

2009-01-01

160

Critical current measurement of HTS tape relating with cable structure for a DC power cable  

NASA Astrophysics Data System (ADS)

In the 200 m high temperature superconducting (HTS) cable test facility at Chubu University, a coaxial power cable is used and composed of two BSCCO (Bi-2223) superconducting layers. The tapes are wound closely to reduce effects on the critical current of BSCCO at self-field. Accordingly, each superconducting layer has a different number of BSCCO tapes. Previously, we have investigated dependence of the critical current (Ic) on the gap in order to optimize the HTS DC cable design. We have been studying the effect on the performance of HTS tapes for the superconducting DC power cables by critical current measurements. In the present experiments several HTS tapes are used and set as a similar structure in the cable with a two-layer structure. The critical current of HTS tapes are measured against the gap between the tapes in the same layer. The experiments show the improvement of the critical current by optimizing the tape arrangements due to magnetic field interaction between the tapes. We will present the experimental results and discuss the design of the HTS DC cable.

Sun, Jian; Watanabe, Hirofumi; Hamabe, Makoto; Kawahara, Toshio; Yamaguchi, Satarou

2014-05-01

161

The surface discharge and breakdown characteristics of HTS DC cable and stop joint box  

NASA Astrophysics Data System (ADS)

A high temperature superconducting (HTS) DC cable system consists of a HTS cable and cable joint. The HTS DC cable should be electrically connected in joint boxes because of the unit length of HTS cable is limited to several-hundred meters. In particular, the stop joint box (SJB) must be developed for a compact cooling system. Polypropylene laminated paper (PPLP) and epoxy maybe used as insulating materials for HTS DC cable and SJB. To develop a HTS DC cable, it is necessary to develop the cryogenic insulation technology, materials and the joint methods. In this paper, we will mainly discuss on the DC and impulse characteristics of epoxy and PPLP in liquid nitrogen (LN2). The surface discharge characteristics of epoxy included fillers, PPLP and epoxy with PPLP composite (epoxy + PPLP) were measured under 0.4 MPa. Also, the PPLP-insulated mini-model cable was fabricated and then DC, impulse and DC polarity reversal breakdown strength of mini-model cable under 0.4 MPa were investigated.

Kim, W. J.; Kim, H. J.; Cho, J. W.; Kim, S. H.

2014-09-01

162

Nonlinear buffer layers relevant for reduced nonlinear effects in HTS microwave devices  

NASA Astrophysics Data System (ADS)

Microwave devices made of a High-Temperature Superconductor (HTS) exhibit a nonlinear response as the microwave power increases. The HTS nonlinearities generate a nonlinear inductance Ld(irf) and a nonlinear resistance Rd(irf) in a device. Ld(irf) and Rd(irf) are responsible for an increase of the device loss, a small frequency dispersion as well as the generation of spurious signals like Intermodulation Distortion (IMD). Nevertheless, the HTS nonlinearities in a microwave device can be reduced using a nonlinear dielectric like a ParaElectric Material (PEM). This assumption has recently been demonstrated theoretically. In a microwave device made of a HTS and a PEM, the nonlinear contribution to the capacitance Cd(vrf) from the PEM acts oppositely to the nonlinear contribution to Ld(irf). This may cancel the effect of the HTS inductive nonlinearities. The PEM also produces a nonlinear conductance Gd(vrf) in a device. All these nonlinear terms contribute to the IMD output power and the nonlinear quality factor (Q0) of a resonant passive microwave device. In this paper, the dependence of the different nonlinear contributions on frequency and applied dc bias voltage (Vdc) is investigated. The relevance to employ PEM in order to reduce the nonlinearities in HTS microwave devices is discussed.

Seron, D.

2008-02-01

163

Characteristics of the magnetic field distribution on compact NMR magnets using cryocooled HTS bulks  

NASA Astrophysics Data System (ADS)

Recently, the performance of high temperature superconducting (HTS) bulks such as critical current density, size, and mechanical strength has been improved rapidly. So, various applications using HTS bulks such as motors, bearings and flywheels have been investigated by many research groups. A compact nuclear magnetic resonance (NMR) magnet is one of the new applications after a technique to enhance maximum trapped field of the HTS bulk more than 11.7 T (500 MHz 1H NMR frequency) has been developed. This new compact NMR magnet out of HTS bulks is cost-effective compared with conventional NMR magnets and then expected to be widely used in food and drug industry. In design and manufacture of the compact NMR magnets, spatial field homogeneity of the large trapped magnetic field in HTS bulk annuli is a crucial issue because the behavior of a trapped field is highly non-linear and, as a result, a technique to improve the field homogeneity such as active/passive shimming now becomes more challenging compared with that of the conventional counterparts. This paper presents the magnetic field distributions in single and three assembled HTS bulk annuli measured by a 3-axis and multi-arrayed Hall sensor under two different cryogenic environments: (1) in a bath of liquid nitrogen (LN 2) and (2) dry cooling by a cryocooler. The spatial homogeneity changes with various operating temperatures were investigated and the effect of critical current density enhancement by lowering the operating temperature on the field homogeneity improvement was discussed in detail.

Kim, S. B.; Takano, R.; Nakano, T.; Imai, M.; Hahn, S. Y.

2009-10-01

164

O2 (1?g) detection using broadband CARS  

NASA Astrophysics Data System (ADS)

1 ?g oxygen was the active medium of chemical oxygen iodine laser (COIL), the concentration and distribution of 1 ?g oxygen was important for the output power and beam quality. However, the current test technique, such as fluorescence detection method, absorption spectrum method could not get accurate 1 ?g oxygen information, due to the interference from the iodine fluorescence or the rigorous request of the laser source and optics and detection elements. The anti-stokes Raman spectrum of 1 ?g oxygen was regarded as a potential technique to obtain desirable signal, and the coherent anti-stokes Raman scatter (CARS) was the most feasible technique to get better signal to noise ratio (SNR). In this paper, we reported a broadband nanosecond coherent anti-stokes Raman scatter (CARS) detecting system built up for the detection of the concentration and distribution of O2( 1 ?g) in COIL?The second harmonic of a Nd: YAG pulse laser was separated into two parts, one part was used to pump a broadband nanosecond dye laser to generate light of 578-580 nm, which covered both stokes lines of O2 ( 1 ?g?and O2 (3 ?? The other part was combined with dye laser output by a dichroic mirror, and then introduced into the detection region of COIL through a focus lens. CARS signals for O2?1 ?g?and O2 ?3 ??have different wavelengths, and their intensity was proportional to the square of the concentration of O2?1 ?g? and O2( 3 ?). By changing the focus spot of pump and stokes laser, the concentration distribution of O2?1 ?g? and O2?3 ??at different position could be obtained.

Liu, Jinbo; Guo, Jingwei; Cai, Xianglong; Gai, Baodong; Meng, Qingkun; Jin, Yuqi

2015-02-01

165

Status and Progress of a Fault Current Limiting Hts Cable to BE Installed in the con EDISON Grid  

NASA Astrophysics Data System (ADS)

In the last decade, significant advances in the performance of second generation (2G) high temperature superconducting wire have made it suitable for commercially viable applications such as electric power cables and fault current limiters. Currently, the U.S. Department of Homeland Security is co-funding the design, development and demonstration of an inherently fault current limiting HTS cable under the Hydra project with American Superconductor and Consolidated Edison. The cable will be approximately 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The underground cable will be installed and energized in New York City. The project is led by American Superconductor teamed with Con Edison, Ultera (Southwire and nkt cables joint venture), and Air Liquide. This paper describes the general goals, design criteria, status and progress of the project. Fault current limiting has already been demonstrated in 3 m prototype cables, and test results on a 25 m three-phase cable will be presented. An overview of the concept of a fault current limiting cable and the system advantages of this unique type of cable will be described.

Maguire, J.; Folts, D.; Yuan, J.; Henderson, N.; Lindsay, D.; Knoll, D.; Rey, C.; Duckworth, R.; Gouge, M.; Wolff, Z.; Kurtz, S.

2010-04-01

166

Wiring up, reaching out.  

PubMed

Taking another step in our Most Wired project, we conducted cyber-interviews with health plans and asked them to tell us just how wired they are. Find out how well they connect to members and employers, which HR and educational services they offer online, and whether they do business with doctors and hospitals electronically. Plus: profiles of major info tech undertakings at six health plans. They range from a $78,000 intranet to a $4 million data warehouse. But while the six projects differ in cost, they overlap in purpose: putting more information into the hands of doctors, hospitals, employers, and consumers. In doing that, they show what being wired is all about. PMID:10404661

Serb, C

1999-05-01

167

Wire brush fastening device  

SciTech Connect

A fastening device is provided which is a variation on the conventional nut and bolt. The bolt has a longitudinal axis and threading helically affixed thereon along the longitudinal axis. A nut having a bore extending therethrough is provided. The bore of the nut has a greater diameter than the diameter of the bolt so the bolt can extend through the bore. An array of wire bristles are affixed within the bore so as to form a brush. The wire bristles extend inwardly from the bore and are constructed and arranged of the correct size, length and stiffness to guide the bolt within the bore and to restrain the bolt within the bore as required. A variety of applications of the wire brush nut are disclosed, including a bolt capture device and a test rig apparatus.

Meigs, R.A.

1993-08-31

168

Wire brush fastening device  

DOEpatents

A fastening device is provided which is a variation on the conventional nut and bolt. The bolt has a longitudinal axis and threading helically affixed thereon along the longitudinal axis. A nut having a bore extending therethrough is provided. The bore of the nut has a greater diameter than the diameter of the bolt so the bolt can extend through the bore. An array of wire bristles are affixed within the bore so as to form a brush. The wire bristles extend inwardly from the bore and are constructed and arranged of the correct size, length and stiffness to guide the bolt within the bore and to restrain the bolt within the bore as required. A variety of applications of the wire brush nut are disclosed, including a bolt capture device and a test rig apparatus.

Meigs, Richard A. (East Concord, NY)

1995-01-01

169

Wire brush fastening device  

DOEpatents

A fastening device is provided which is a variation on the conventional nut and bolt. The bolt has a longitudinal axis and threading helically affixed thereon along the longitudinal axis. A nut having a bore extending therethrough is provided. The bore of the nut has a greater diameter than the diameter of the bolt so the bolt can extend through the bore. An array of wire bristles are affixed within the bore so as to form a brush. The wire bristles extend inwardly from the bore and are constructed and arranged of the correct size, length and stiffness to guide the bolt within the bore and to restrain the bolt within the bore as required. A variety of applications of the wire brush nut are disclosed, including a bolt capture device and a test rig apparatus. 13 figs.

Meigs, R.A.

1995-09-19

170

Neon turbo-Brayton cycle refrigerator for HTS power machines  

NASA Astrophysics Data System (ADS)

We developed a prototype turbo-Brayton refrigerator whose working fluid is neon gas. The refrigerator is designed for a HTS (High Temperature Superconducting) power transformer and its cooling power is more than 2 kW at 65 K. The refrigerator has a turboexpander and a turbo-compressor, which utilize magnetic bearings. These rotational machines have no rubbing parts and no oil-components. Those make a long maintenance interval of the refrigerator. The refrigerator is very compact because our newly developed turbo-compressor is volumetrically smaller than a displacement type compressor in same operating specification. Another feature of the refrigerator is a wide range operation capability for various heat-loads. Cooling power is controlled by the input-power of the turbo-compressor instead of the conventional method of using an electric heater. The rotational speed of the compressor motor is adjusted by an inverter. This system is expected to be more efficient. We show design details, specification and cooling test results of the new refrigerator in this paper.

Hirai, Hirokazu; Hirokawa, M.; Yoshida, Shigeru; Nara, N.; Ozaki, S.; Hayashi, H.; Okamoto, H.; Shiohara, Y.

2012-06-01

171

Large Coaxial Coldfinger Ptc for Process Liquefaction and Hts Applications  

NASA Astrophysics Data System (ADS)

Large (>100 W cooling capacity at 80 K) `pulse-tube' coolers are ideal candidates for emerging applications such as HTS transmission lines, transformers, and motor windings, meso-scale oxygen liquefaction on-demand, cryopumping, and cryogen boiloff recovery. A number of successful large `in-line' pulse-tube coolers have been built, but these require embedded shell-and-tube process heat exchangers, hence transport of the process fluid/gas to and from the coldhead, and often a high degree of process fluid purity, to avoid clogging in the narrow inlets and outlets of these heat exchangers. It is far preferable in most circumstances to have a coldfinger design that presents a salient cold tip, with the coldhead at the end of a flexible transfer line, as is done with Gifford-McMahon or Joule-Thomson coolers. This paper presents some design details and data from the development of our first high-capacity coldfinger, as well as the results of its application to a 55 gallon/day oxygen liquefier for the Navy.

Spoor, P. S.; Corey, J. A.

2010-04-01

172

Triaxial HTS Cable for the AEP Bixby Project  

SciTech Connect

Ultera has installed a single 200-meter long high temperature superconducting (HTS) 3-phase triaxial design cable at the American Electric Power (AEP) Bixby substation in Columbus, Ohio. The cable connects a 132/13.8 kV transformer to the distribution switchgear serving seven outgoing circuits. It was designed to carry 3000 Arms. Testing of 3- to 5-meter length prototype cables, including a 5-meter prototype with full scale terminations tested at ORNL was conducted prior to the manufacture and installation of the AEP triaxial cable. These prototypes were used to demonstrate the crucial operating conditions including steady state operation at the 3000 Arms design current, high voltage operation, high voltage withstand and 110 kV impulse, and overcurrent fault capability. A summary of the results from the thermal analysis and testing conducted by Ultera and ORNL will be presented. Some analysis of the cable thermal-hydraulic response based on the testing that were used to determine some of the cable cryogenic system requirements are also presented.

Demko, Jonathan A [ORNL; Gouge, Michael J [ORNL; Lindsay, David T [ORNL; Roden, Mark L [ORNL; Tolbert, Jerry Carlton [ORNL

2007-01-01

173

One hundred angstrom niobium wire  

NASA Technical Reports Server (NTRS)

Composite of fine niobium wires in copper is used to study the size and proximity effects of a superconductor in a normal matrix. The niobium rod was drawn to a 100 angstrom diameter wire on a copper tubing.

Cline, H. E.; Rose, R. M.; Wulff, J.

1968-01-01

174

Engineering Nanocolumnar Defect Configurations for Optimized Vortex Pinning in High Temperature Superconducting Nanocomposite Wires  

SciTech Connect

High temperature superconducting (HTS), coated conductor wires based on nanocomposite films containing self-assembled, insulating BaZrO3 (BZO) nanocolumnar defects have previously been reported to exhibit enhanced vortex pinning. Here, we report on microstructural design via control of BZO nanocolumns density in YBa2Cu3O7- (YBCO)+BZO nancomposite films to achieve the highest critical current density, Jc(H, ,T). X-ray diffraction and microstructural examination shows increasing number density of epitaxial BZO nanocolumns in the highly cube-textured YBCO matrix with increasing nominal BZO additions. Transport property measurement reveals that an increase in BZO content upto 4 vol% is required to sustain the highest pinning and Jc performance as the magnetic field increases. By growing thicker, single-layer nanocomposite films (~4 m) with controlled density of BZO columnar defects, the critical current (Ic) of ~1000 A/cm at 77 K, self-field and the minimum Ic of 455 A/cm at 65 K and 3 T for all magnetic field orientations were obtained. This is the highest Ic reported to date for films on metallic templates which are the basis for the 2nd generation, coated conductor-based HTS wires.

Wee, Sung Hun [ORNL; Zuev, Yuri L [ORNL; Cantoni, Claudia [ORNL; Goyal, Amit [ORNL; Ahuja, Raj [Waukesha Electric Systems Inc.; Abiade, J. [North Carolina A& T State University

2013-01-01

175

49 CFR 234.231 - Fouling wires.  

Code of Federal Regulations, 2010 CFR

...when the train detection circuit is shunted. Installation of a single duplex wire with single plug acting as fouling wires is prohibited. Existing installations having single duplex wires with a single plug for fouling wires may be continued in...

2010-10-01

176

Wire EDM for Refractory Materials  

NASA Technical Reports Server (NTRS)

In an attempt to reduce fabrication time and costs, Wire Electrical Discharge Machine (Wire EDM) method was investigated as tool for fabricating matched blade roots and disk slots. Eight high-strength nickel-base superalloys were used. Computer-controlled Wire EDM technique provided high quality surfaces with excellent dimensional tolerances. Wire EDM method offers potential for substantial reductions in fabrication costs for "hard to machine" alloys and electrically conductive materials in specific high-precision applications.

Zellars, G. R.; Harris, F. E.; Lowell, C. E.; Pollman, W. M.; Rys, V. J.; Wills, R. J.

1982-01-01

177

Wires by Patchy Particles  

NSDL National Science Digital Library

Simulation Software: Glotzer Group Code Simulation Method: Brownian Dynamics A system of 80 spherical particles with two patches at a concentration of 0.20, was run starting at an effectively infinite temperature then instantaneously quenched to a temperature of 0.5. The final equillibrium structure is wires or chains. Simulation Model: United Atom Rigid Body with Lennard-Jones

Zhang, Zhenli

2005-01-31

178

A World without Wires  

ERIC Educational Resources Information Center

The wireless bandwagon is rolling across Mississippi, picking up a fresh load of converts and turning calamity into opportunity. Traditional wired school networks, many of which unraveled during Hurricane Katrina, are giving way to advanced wireless mesh networks that frequently include voice-over-IP (VoIP) capabilities. Vendor funding is helping…

Panettieri, Joseph C.

2006-01-01

179

SPACEWAR WIRE MILITARY SPACE  

E-print Network

TERRORWARS SPACEDAILY TERRADAILY MARSDAILY SPACE TRAVEL SPACEMART SPACE DATABASE Endangered Species WeCHANNELS SPACEWAR WIRE MILITARY SPACE UAV NEWS MILITARY COMMS CYBERWARS MISSILE NEWS RAYGUNS project Nepal jails six soldiers for murder, human rights violations Ex-Peruvian spy chief wants CIA

180

Basic Wiring. Second Edition.  

ERIC Educational Resources Information Center

This guide is designed to assist teachers conducting a foundation course to prepare students for additional courses of training for entry-level employment in either the residential or commercial and industrial wiring trades. Included in the guide are 17 instructional units and the following sections of information for teachers: guidelines in using…

Kaltwasser, Stan; And Others

181

Residential Wiring. Second Edition.  

ERIC Educational Resources Information Center

This guide is designed to assist teachers conducting a course to prepare students for entry-level employment in the residential wiring trade. Included in the guide are six instructional units and the following sections of information for teachers: guidelines in using the unit components; academic and workplace skills classifications and…

Taylor, Mark; And Others

182

Improved wire chamber  

DOEpatents

An improved gas mixture for use with proportional counter devices, such as Geiger-Mueller tubes and drift chambers. The improved gas mixture provides a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor. 2 figs.

Atac, M.

1987-05-12

183

NewsWire, 2002.  

ERIC Educational Resources Information Center

This document presents the 3 2002 issues of the newsletter "NewsWire," (volume 5). Issue Number One focuses on collaborative Web projects. This issue begins with descriptions of four individual projects: "iEARN"; "Operation RubyThroat"; "Follow the Polar Huskies!"; and "Log in Your Animal Roadkill!" Features that follow include: "Bringing the…

Byrom, Elizabeth, Ed.; Bingham, Margaret, Ed.; Bowman, Gloria, Ed.; Shoemaker, Dan, Ed.

2002-01-01

184

1997 wire development workshop: Proceedings  

SciTech Connect

This conference is divided into the following sections: (1) First Generation Wires I; (2) First Generation Wires II; (3) Coated conductors I; and (4) Coated conductors II. Applications of the superconducting wires include fault current limiters, superconducting motors, transformers, and power transmission lines.

NONE

1997-04-01

185

Wire vibration, bowing, and breakage in wire electrical discharge machining  

NASA Astrophysics Data System (ADS)

This article provides an analysis of the wire electrical discharge machining (EDM) process. The causes of wire vibration, bowing, and breakage are identified. The cross sectional configuration of an eroded wire is derived from basic physics under the assumption that the erosion rate is constant. This configuration is verified experimentally with further explanation as to why numerous experimental studies have yielded different configurations. A computational model has been developed that can evaluate the systematic effects that lead to wire breakage by determining the stress induced by wire erosion and the stress induced by the sparks during the operation of a wire-cutting EDM machine. This model is also capable of determining the extent of wire bowing and vibrations in these machines but only in the frontal direction. The model is supported by data from experiments performed on an AGIECUT 612 wire machine cutting a 10 mm high copper bar with a 0.15 mm brass wire to acquire wire breakage data. The nearly parabolic shape of the bowed wire agrees with the results of other authors making more restrictive assumptions.

Arunachalam, C.; Aulia, M.; Bozkurt, B.; Eubank, P. T.

2001-04-01

186

Numerical Analysis of Heat Transfer and Fluid Characteristics in Long Distance HTS Cable  

NASA Astrophysics Data System (ADS)

Japanese national project, called "Materials & Power applications of Coated Conductors (M-PACC)", started in FY2008. In this project, high temperature superconducting (HTS) cable using REBCO tapes has been developing. These HTS cables are expected as a compact size with large capacity and low loss power transmission. In the future, it is supposed that these cables will be installed in power grid for replacing existing power cables. Under the operating HTS cable in the power grid, it is necessary that the REBCO tapes in the long distance cable are kept cooling at low temperature stably and efficiently by liquid nitrogen (LN2). In this paper, the flow characteristic, such as pressure drop of LN2 flowing in the long distance HTS cable, and the heat transfer characteristic against heat generation, such as AC loss, and heat leak from cryostat-pipes were analytically estimated with varying the volumetric flow and the diameter of outer pipe wall which are parameters easy to control in cable system design. As a result, it was confirmed that the volumetric flow increasing is affective to extending the maximum distance which can be transmitted but it required increasing discharge pressure too. This increasing discharge pressure can be restricted without affecting the longitudinal distribution of the HTS temperature by expanding of the diameter of outer pipe wall.

Maruyama, O.; Ohkuma, T.; Izumi, T.

187

MScreen: An Integrated Compound Management and High Throughput Screening (HTS) Data Storage and Analysis System  

PubMed Central

High-throughput screening (HTS) has historically been used by the pharmaceutical industry to rapidly test hundreds of thousands of compounds to identify potential drug candidates. More recently, academic groups have used HTS to identify new chemical probes or small interfering RNA (siRNA) that can serve as experimental tools to examine the biology or physiology of novel proteins, processes, or interactions. HTS presents a significant challenge with the vast and complex nature of data generated. This report describes MScreen, a web-based, open-source cheminformatics application for chemical library and siRNA plate management, primary HTS and dose-response data handling, structure search, and administrative functions. Each project in MScreen can be secured with passwords or shared in an open information environment which enables collaborators to easily compare data from many screens, providing a useful means to identify compounds with desired selectivity. Unique features include compound, substance, mixture, and siRNA plate creation and formatting; automated dose-response fitting and quality control (QC); and user, target, and assay method administration. MScreen provides an effective means to facilitate HTS information handling and analysis in the academic setting so that users can efficiently view their screening data and evaluate results for follow-up. PMID:22706349

Jacob, Renju T.; Larsen, Martha J.; Larsen, Scott D.; Kirchhoff, Paul D.; Sherman, David H.; Neubig, Richard R.

2013-01-01

188

Strengthening future electricity grid of the Netherlands by integration of HTS transmission cables  

NASA Astrophysics Data System (ADS)

The electricity grid of the Netherlands is changing. There is a call of society to use more underground cables, less overhead lines (OHL) and to reduce magnetic emissions. At the same time, parts of the future transmission grid need strengthening depending on the electricity demand in the coming decades [1]. Novel high temperature superconductor (HTS) AC transmission cables can play a role in strengthening the grid. The advantages as compared to alternatives, are: economic, underground, higher power capacity, lower losses, reduced magnetic field emissions in (existing) OHL, compact: less occupation of land and less permits needed, a possibility to keep 380 kV voltage level in the grid for as long as needed. The main obstacles are: the relatively high price of HTS tapes and insufficient maturity of the HTS cable technology. In the paper we focus on a 34 km long connection in the transmission grid (to be strengthened in three of the four of TenneT scenarios [1]), present the network study results, derive the requirements for corresponding HTS transmission cable system and compare HTS system to the alternatives (OHLs and XLPE cables).

Zuijderduin, Roy; Chevtchenko, Oleg; Smit, Johan; Aanhaanen, Gert; Ross, Rob

2014-05-01

189

Insulation and Heat Treatment of Bi-2212 Wire for Wind-and-React Coils  

SciTech Connect

Higher Field Magnets demand higher field materials such as Bi-2212 round superconducting wire. The Bi-2212 wire manufacture process depends on the coil fabrication method and wire insulation material. Considering the wind-and-react method, the coil must unifirmly heated to the melt temperature and uniformly cooled to the solidification temperature. During heat treat cycle for tightly wound coils, the leakage melt from conductor can chemically react with insulation on the conductor and creat short turns in the coils. In this research project, conductor, insulation, and coils are made to systemically study the suitable insulation materials, coil fabrication method, and heat treatment cycles. In this phase I study, 800 meters Bi-2212 wire with 3 different insulation materials have been produced. Best insulation material has been identified after testing six small coils for insulation integrity and critical current at 4.2 K. Four larger coils (2" dia) have been also made with Bi-2212 wrapped with best insulation and with different heattreatment cycle. These coils were tested for Ic in a 6T background field and at 4.2 K. The test result shows that Ic from 4 coils are very close to short samples (1 meter) result. It demonstrates that HTS coils can be made with Bi-2212 wire with best insulation consistently. Better wire insulation, improving coil winding technique, and wire manufacture process can be used for a wide range of high field magnet application including acclerators such as Muon Collider, fusion energy research, NMR spectroscopy, MRI, and other industrial magnets.

Peter K. F. Hwang

2007-10-22

190

Stress Analysis of a High Temperature Superconductor Coil Wound With Bi-2223/Ag Tapes for High Field HTS/LTS NMR Magnet Application  

E-print Network

The electromagnetic stress distribution inside a HTS insert is one of the key issues for construction of a high field high/low temperature superconductor (HTS/LTS) magnet. The rmiddotJmiddotB formulae is widely used for ...

Kiyoshi, Tsukasa

191

The Role of HTS in Drug Discovery at the University of Michigan  

PubMed Central

High throughput screening (HTS) is an integral part of a highly collaborative approach to drug discovery at the University of Michigan. The HTS lab is one of four core centers that provide services to identify, produce, screen and follow-up on biomedical targets for faculty. Key features of this system are: protein cloning and purification, protein crystallography, small molecule and siRNA HTS, medicinal chemistry and pharmacokinetics. Therapeutic areas that have been targeted include anti-bacterial, metabolic, neurodegenerative, cardiovascular, anti-cancer and anti-viral. The centers work in a coordinated, interactive environment to affordably provide academic investigators with the technology, informatics and expertise necessary for successful drug discovery. This review provides an overview of these centers at the University of Michigan, along with case examples of successful collaborations with faculty. PMID:24409957

Larsen, Martha J.; Larsen, Scott D.; Fribley, Andrew; Grembecka, Jolanta; Homan, Kristoff; Mapp, Anna; Haak, Andrew; Nikolovska-Coleska, Zaneta; Stuckey, Jeanne A.; Sun, Duxin

2014-01-01

192

Reliability Test of a 1-kW Pulse Tube Cryocooler for Hts Cable Application  

NASA Astrophysics Data System (ADS)

The recent progress of a large Stirling-type pulse tube cryocooler is reported based on 24/7 operation since August 2008 in a high temperature superconducting (HTS) cable application at American Electric Power's (AEP) Bixby Road substation in Columbus, OH. The 20-kW pressure wave generator (PWG) has been upgraded to a second generation design. The in-line configured pulse tube coldhead, rated at 1 kW at 77 K, was developed by Praxair. The objective of the continued testing at the HTS cable demonstration facility is to accumulate cryocooler operating hours and demonstrate system reliability. The cryocooler uses a parallel flow from the main vacuum subcooling refrigerator then both flows are supplied to the HTS cable inlet. The cryocooler operation has shown consistent results with satisfactory cooling performance. The field demonstrated thermodynamic efficiency is 15% of Carnot at 72 K.

Chen, R.-L.; Henzler, G. W.; Royal, J. H.; Billingham, J. F.

2010-04-01

193

Voltage-current characteristics of two soldered 2G HTS tapes  

NASA Astrophysics Data System (ADS)

Most prospective 2G HTS are asymmetric in cross section due to technology feature. Superconducting layer is located more close to one side of a tape, while from the other side highly resistive substrate is located. Thus, it is possible to combine two 2G HTS tapes with different mutual orientations of superconducting layers. In this work we studied voltage current characteristics (VCC) of eight samples made of two soldered HTS tapes (copper coated SCS4050 tapes from Super Power Inc.). Connection of samples to terminations varied as well. VCC measured were different depending on tapes' combining method, joint to terminations and external magnetic fields. Peculiarities on VCC were indicated a current transfer between tapes. Possible explanation of the phenomenon is discussed also.

Vysotsky, V. S.; Radchenko, I. P.; Fetisov, S. S.; Sytnikov, V. E.; Zubko, V. V.

2010-06-01

194

Dental Arch Wire  

NASA Technical Reports Server (NTRS)

Straightening teeth is an arduous process requiring months, often years, of applying corrective pressure by means of arch wires-better known as brace-which may have to be changed several times in the course of treatment. A new method has been developed by Dr. George Andreasen, orthodontist and dental scientist at the University of Iowa. The key is a new type of arch wire material, called Nitinol, with exceptional elasticity which helps reduce the required number of brace changes. An alloy of nickel and titanium, Nitinol was originally developed for aerospace applications by the Naval Ordnance Laboratory, now the Naval Surface Weapons Laboratory, White Oaks, Maryland. NASA subsequently conducted additional research on the properties of Nitinol and on procedures for processing the metal.

1979-01-01

195

Operating characteristics of HTS power supply for and improving temporal stability of coated conductor magnet in liquid helium  

Microsoft Academic Search

High temperature superconducting (HTS) magnets have been studied for insert coils of high field nuclear magnetic resonance (NMR) magnets but the temporal stability required for NMR is hard to achieve due to low index value and high joint resistance. In this research, the HTS power supply with magnets using coated conductor (CC) was investigated and tested in helium cryogenic system.

D. K. Park; Y. J. Kim; S. E. Yang; N. Y. Kwon; H. G. Lee; T. K. Ko

2009-01-01

196

Superconducting magnet wire  

DOEpatents

A superconducting tape or wire with an improved critical field is formed of alternating layers of a niobium-containing superconductor such as Nb, NbTi, Nb.sub.3 Sn or Nb.sub.3 Ge with a thickness in the range of about 0.5-1.5 times its coherence length, supported and separated by layers of copper with each copper layer having a thickness in the range of about 170-600 .ANG..

Schuller, Ivan K. (Woodridge, IL); Ketterson, John B. (Evanston, IL); Banerjee, Indrajit (San Jose, CA)

1986-01-01

197

Wiring for aerospace applications  

NASA Astrophysics Data System (ADS)

In this paper, the authors summarize the current state of knowledge of arc propagation in aerospace power wiring and efforts by the National Aeronautics and Space Administration (NASA) towards the understanding of the arc tracking phenomena in space environments. Recommendations will be made for additional testing. A database of the performance of commonly used insulating materials will be developed to support the design of advanced high power missions, such as Space Station Freedom and Lunar/Mars Exploration.

Christian, J. L., Jr.; Dickman, J. E.; Bercaw, R. W.; Myers, I. T.; Hammoud, A. N.; Stavnes, M.; Evans, J.

1992-07-01

198

Wire Diffraction Gratings  

NASA Astrophysics Data System (ADS)

In the summer of 1972, I attended the workshop on recreating classic experiments in physics at Barnard College. This was developed by Samuel Devons, and it was a defining experience that set me toward a research career involving early physics teaching apparatus. During the course of the workshop, I became curious about the original diffraction gratings developed by Fraunhofer and built a wire diffraction. A short note about the gratings was published in the American Journal of Physics the next year.2

Greenslade, Thomas B.

2004-02-01

199

Wiring for aerospace applications  

NASA Technical Reports Server (NTRS)

In this paper, the authors summarize the current state of knowledge of arc propagation in aerospace power wiring and efforts by the National Aeronautics and Space Administration (NASA) towards the understanding of the arc tracking phenomena in space environments. Recommendations will be made for additional testing. A database of the performance of commonly used insulating materials will be developed to support the design of advanced high power missions, such as Space Station Freedom and Lunar/Mars Exploration.

Christian, J. L., Jr.; Dickman, J. E.; Bercaw, R. W.; Myers, I. T.; Hammoud, A. N.; Stavnes, M.; Evans, J.

1992-01-01

200

Numerical Analysis of Heat Transfer and Fluid Characteristics of Flowing Liquid Nitrogen in HTS Cable  

NASA Astrophysics Data System (ADS)

High-temperature superconducting (HTS) cable has heat intrusion from the termination including joule heat generation at the terminal joint and from the room temperature cable through the Cu current lead. According to the length of the HTS cable, this heat loss may become a considerable amount which cannot be ignored in the HTS cable system. In this study, referring to a high-voltage cable (HV cable) which was developed in M-PACC project, the effect of heat transfer at the interface between the terminal joint and LN2 in the terminal vessel (ho) on the temperature of the HTS cable were calculated and evaluated. The condition of flow in the terminal vessel was assumed to be natural convection, forced flow or static condition for evaluating this effect with various heat transfer condition. As a result, in the case of the natural convection, most of heats flow into the LN2 in the terminal vessel where the volumetric flow of the LN2 is large since ho becomes high. Accordingly, the temperature rise of the LN2 in the inner pipe of Cu former and the terminal vessel can be restricted. However, in the cases of the forced flow and the static condition, most of heats flow into the LN2 in the inner pipe where the volumetric flow of the LN2 is small since ho becomes small. Accordingly, the temperature rise of the LN2 in the inner pipe becomes high. This temperature rise of the LN2 in the inner pipe makes the temperature of the HTS conductor large resulting in remarkable increase of AC losses. Consequently, on the HV cable design, for restriction of the AC loss increase, it is expected that designing the HTS cable termination such as extending outer surface of the terminal joint for increasing of the heat inflow from the terminal joint to the LN2 in the vessel is effective.

Maruyama, O.; Ohkuma, T.; Izumi, T.; Shiohara, Y.

201

Joining Part 1g ME 6222: Manufacturing Processes and Systems  

E-print Network

: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2009 4 ­ aluminum, tin #12;Ultrasonic weldingJoining ­ Part 1g ver. 1 ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2009 · Soldering and brazingSoldering and brazing · Fusion welding ME 6222: Manufacturing Processes and Systems

Colton, Jonathan S.

202

A Study on the Body Insulators for the Bushing for HTS Devices at Cryogenic Temperature  

NASA Astrophysics Data System (ADS)

A bushing for high temperature superconducting devices (HTS bushing) is important because of applying high voltage to the cable or the winding of the transformer. It is cooled with liquid nitrogen (LN2) and is insulated with various insulators. For the development of the HTS bushing, it is necessary to know the fundamental characteristics of various insulators at cryogenic temperature. The electrical characteristics of the breakdown were studied under AC and impulse voltages. Also, the mechanical characteristics such as tensile strength in air and LN2 were studied. It was confirmed that GFRP is excellent not only electrical characteristics but also mechanical characteristics in LN2.

Kim, W. J.; Shin, H. S.; Kim, S. H.

203

Development of 16 kA HTS current leads for 40 T hybrid magnet application  

NASA Astrophysics Data System (ADS)

A pair of 16 kA high temperature superconducting current leads which will serve a 40 T hybrid magnet at the CHMFL was designed, manufactured and performed the factory acceptance test at the ASIPP site. The major design includes the LN2-cooling copper heat exchanger part as well as the HTS module made of BSCCO 2223/AgAu matrix tapes in parallel which allows the operation of the current lead at a minimum coolant mass flow. The paper briefly describes the design of the 16 kA HTS current leads. And the cold test results of current leads are also presented in the paper.

Bi, Y.; Ding, K.; Feng, H.; Liu, C.; Liu, X.; Lu, K.; Wu, H.; Song, Y.; Xu, C.; Ye, B.; Zhou, T.

2014-05-01

204

Numerical investigations on applicability of permanent magnet method to crack detection in HTS film  

NASA Astrophysics Data System (ADS)

The scanning permanent-magnet (PM) method was originally developed for determining the spatial distribution of the critical current density in a high-temperature superconducting (HTS) film. In the present study, its applicability to the crack detection in an HTS film is investigated numerically. To this end, a defect parameter is defined for characterizing a crack position and it is calculated along various scanning lines. The results of computations show that, only when the scanning position is near a crack, the defect parameter shows a violent change. On the basis of the behavior of the defect parameter, the method for roughly identifying a crack is also proposed.

Kamitani, A.; Takayama, T.; Saitoh, A.

2014-09-01

205

Dual wire welding torch and method  

DOEpatents

A welding torch includes a nozzle with a first welding wire guide configured to orient a first welding wire in a first welding wire orientation, and a second welding wire guide configured to orient a second welding wire in a second welding wire orientation that is non-coplanar and divergent with respect to the first welding wire orientation. A method of welding includes moving a welding torch with respect to a workpiece joint to be welded. During moving the welding torch, a first welding wire is fed through a first welding wire guide defining a first welding wire orientation and a second welding wire is fed through a second welding wire guide defining a second welding wire orientation that is divergent and non-coplanar with respect to the first welding wire orientation.

Diez, Fernando Martinez (Peoria, IL); Stump, Kevin S. (Sherman, IL); Ludewig, Howard W. (Groveland, IL); Kilty, Alan L. (Peoria, IL); Robinson, Matthew M. (Peoria, IL); Egland, Keith M. (Peoria, IL)

2009-04-28

206

Wire detecting apparatus and method  

SciTech Connect

This invention is comprised of an apparatus and method that combines a signal generator and a passive signal receiver to detect and record the path of partially or completely concealed electrical wiring without disturbing the concealing surface. The signal generator applies a series of electrical pulses to the selected wiring of interest. The applied pulses create a magnetic field about the wiring that can be detected by a coil contained within the signal receiver. An audible output connected to the receiver and driven by the coil reflects the receiver`s position with respect to the wiring. The receiver`s audible signal is strongest when the receiver is directly above the wiring and the long axis of the receiver`s coil is parallel to the wiring. A marking means is mounted on the receiver to mark the location of the wiring as the receiver is directed over the wiring`s concealing surface. Numerous marks made on various locations of the concealing surface will trace the path of the wiring of interest.

Kronberg, J.W.

1991-12-31

207

Manually Operated Welding Wire Feeder  

NASA Technical Reports Server (NTRS)

A manual welding wire feeder apparatus comprising a bendable elongate metal frame with a feed roller mounted at the center thereof for rotation about an axis transverse to the longitudinal axis of the frame. The frame ends are turned up as tabs and each provided with openings in alignment with each other and the mid-width center of the roller surface. The tab openings are sized to accommodate welding wire and each extends to a side edge of the tab, both opening on the same side of the frame, whereby welding wire can be side-loaded onto the frame. On the side of the frame, opposite the roller a lock ring handle is attached tangentially and is rotatable about the attachment point and an axis perpendicular to the frame. The device is grasped in the hand normally used to hold the wire. A finger is placed through the loop ring and the frame positioned across the palm and lower fingers. The thumb is positioned atop the wire so it can be moved from the back of the frame across the roller, and towards the front. In doing so, the wire is advanced at a steady rate in axial alignment with the tab openings and roller. To accommodate different wire diameters the frame is bendable about its center in the plane of the frame axis and wire so as to keep the wire in sufficient tension against the roller and to keep the wire fixed when the frame is tilted and thumb pressure released.

Rybicki, Daniel J. (Inventor)

2001-01-01

208

Assembly Using X-Wire™ Insulated Bonding Wire Technology  

Microsoft Academic Search

As the semiconductor industry continues to move towards higher pin count, finer pitch, multi-row and multi- stack devices, wire bonding becomes an increasing challenge for today's advanced packaging processes. Insulated bonding wire technology, known as X-Wire™, has been identified on the 2006 ITRS Roadmap for Semiconductors (1), as a viable, cost-effective solution to enable complex package designs, enhance package performance,

Robert Lyn

2007-01-01

209

Reduction in wire tension caused by wire clamping and wire tensioner removal: an experimental Ilizarov frame study.  

PubMed

The stability of an external ring fixator mainly depends on wire tension. Wire fixators should maintain the tension during both wire clamping to the ring and removal of the tensioner device. In the present study the loss in wire tension related to fixator clamping and wire tensioner removal using three different wire fixator designs was studied. The fixators were based on two different cannulated bolts and a washer. Effects from two different pretension levels in combination with three different bolt torque levels upon loss in wire tension were described. Emitted wire vibration frequency was used to assess the corresponding wire tension. Wire tension was determined after each wire fixator tightening and after the removal of the wire tensioner. Increased bolt torque led to a small decrease in tension for both pretension levels. A considerable higher tension loss was measured when removing the wire tensioner. In all cases, the combination of a new cannulated bolt and a washer maintained the highest tension. PMID:21485324

La Russa, Valentina; Skallerud, Bjørn; Klaksvik, Jomar; Foss, Olav A

2011-03-01

210

Homogenous BSCCO-2212 Round Wires for Very High Field Magnets  

SciTech Connect

The performance demands on modern particle accelerators generate a relentless push towards higher field magnets. In turn, advanced high field magnet development places increased demands on superconducting materials. Nb3Sn conductors have been used to achieve 16 T in a prototype dipole magnet and are thought to have the capability for {approx}18 T for accelerator magnets (primarily dipoles but also higher order multipole magnets). However there have been suggestions and proposals for such magnets higher than 20 T. The High Energy Physics Community (HEP) has identified important new physics opportunities that are enabled by extremely high field magnets: 20 to 50 T solenoids for muon cooling in a muon collider (impact: understanding of neutrinos and dark matter); and 20+ T dipoles and quadrupoles for high energy hadron colliders (impact: discovery reach far beyond present). This proposal addresses the latest SBIR solicitation that calls for grant applications that seek to develop new or improved superconducting wire technologies for magnets that operate at a minimum of 12 Tesla (T) field, with increases up to 15 to 20 T sought in the near future (three to five years). The long-term development of accelerator magnets with fields greater than 20 T will require superconducting wires having significantly better high-field properties than those possessed by current Nb{sub 3}Sn or other A15 based wires. Given the existing materials science base for Bi-2212 wire processing, we believe that Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} (Bi-2212) round wires can be produced in km-long piece lengths with properties suitable to meet both the near term and long term needs of the HEP community. The key advance will be the translation of this materials science base into a robust, high-yield wire technology. While the processing and application of A15 materials have advanced to a much higher level than those of the copper oxide-based, high T{sub c} (HTS) counterparts, the HTS materials have the very significant advantage of an extremely high H{sub c2}. For this reason, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub y} (Bi-2212, or 2212) in the form of a multifilamentary Ag alloy matrix composite is beginning to attract the interest of the magnet community for future extremely high-field magnets or magnet-insert coils for 4.2K operation. Fig. 1 shows an example of excellent JE (engineering current density) in Bi-2212 round wire at fields up to 45 T, demonstrating the potential for high field applications of this material. For comparison, the Nb{sub 3}Sn wires used in magnets in the 16-18 T range typically perform with J{sub E} in the range 200-500 A/mm{sup 2}; the Bi-2212 wire retains this level of performance to fields at least as high as 45 T, and probably significantly higher. Bi-2212 conductors have in fact been used to generate a 25 T field in a superconducting insert magnet. These two factors- the very high field critical current performance of Bi-2212, and the already demonstrated capability of this material for high field magnets up to 25 T, strongly suggest this material as a leading contender for the next generation high field superconducting (HFS) wire. This potential was recognized by the US Academy of Science's Committee on Opportunities in High Magnetic Field Science. Their report of the same name specifically calls out the high field potential for this material, and suggests that 30 T magnets appear feasible based on the performance of 2212. There are several requirements for HFS conductors. The most obvious is J{sub E} (B, T), the engineering current density at the field and temperature of operation. As shown in Fig. 1, Bi-2212 excels in this regard. Stability requirements for magnets dictate that the effective filament diameter should be less than 30 micrometers, something that Bi-2212 multifilamentary wire can uniquely satisfy among the HFS superconducting wire technologies. Additional requirements include mechanical properties that prevent stress limitation of J{sub E} at the operating conditions, resistive transition index (n-value) suffic

Dr. Scott Campbell

2012-06-30

211

Review of wire chamber aging  

SciTech Connect

This paper makes an overview of the wire chamber aging problems as a function of various chamber design parameters. It emphasizes the chemistry point of view and many examples are drawn from the plasma chemistry field as a guidance for a possible effort in the wire chamber field. The paper emphasizes the necessity of variable tuning, the importance of purity of the wire chamber environment, as well as it provides a practical list of presently known recommendations. In addition, several models of the wire chamber aging are qualitatively discussed. The paper is based on a summary talk given at the Wire Chamber Aging Workshop held at LBL, Berkeley on January 16-17, 1986. Presented also at Wire Chamber Conference, Vienna, February 25-28, 1986. 74 refs., 18 figs., 11 tabs.

Va'Vra, J.

1986-02-01

212

Association of migraine and ESR1 G325C polymorphism.  

PubMed

Migraine is a genetically complex disorder in which sexual hormones influence the phenotype. ESR1 G594A polymorphism has been associated with migraine in Australians. We performed a case-control study with G594A and G325C polymorphisms to determine whether ESR1 is associated with migraine in our population. An association between G594A and migraine could not be demonstrated here. By contrast, we observed that the C325 allele conferred a 1.6 (95% confidence interval=1.1-2.4) higher risk for suffering from migraine in women than the G allele. Women carrying the C352C genotype were over 3 times more likely to suffer from migraine than those carrying the G325G genotype. Therefore, we conclude that ESR1 G325C polymorphism is associated with migraine in our population. PMID:16361951

Oterino, Agustín; Pascual, Julio; Ruiz de Alegría, Carlos; Valle, Natalia; Castillo, Jesús; Bravo, Yolanda; González, Félix; Sánchez-Velasco, Pablo; Cayón, Amalia; Leyva-Cobián, Francisco; Alonso-Arranz, Ana; Muñoz, Pedro

2006-01-23

213

The 1 ?g cosyntropin test in normal individuals: A reappraisal  

PubMed Central

Background: The 1?g cosyntropin test has some advantages over the 250?g test as a test of adrenal function. One of the concerns regarding the 1 ?g test includes stability of the cosyntropin when reconstituted and stored. Classically the 5th percentile responses to cosyntropin in normal individuals have been used to define a normal response. Recent studies have shown that these normative values should be determined for individual assays. Materials and Methods: We performed a 1?g cosyntropin test using reconstituted and refrigerated (4-8° C) cosyntropin in saline solution in 49 non pregnant adults who were apparently healthy and had no exposure to exogenous glucocorticoids. The cosyntropin solution was stored for up to 60 days following reconstitution. We analysed the data for any association between duration of cosyntropin solution storage and the cortisol responses to cosyntropin administration. Results: The mean ± SD cortisol level at baseline, 30 and 60 min were-12.19 ± 3 ?g/dl, 20.72 ± 2.63 ?g/dl, 16.86 ± 3.33 ?g/dl. The 5th percentile cortisol response at 30 min was 16.5 ?g/dl (16.33 ?g/dl rounded off). The correlation coefficients between number of days of cosyntropin solution storage and the cortisol responses at 30 and 60 min were (Spear mans rho = 0.06,-0.24 respectively) (P = 0.69 and 0.41). There were no differences in cortisol values whether the storage was for less than 30 days or more than 30 days (mean difference 0.25 ?g/dl P = 0.44). Conclusion: The 5th percentile normative values determined for our assay is lower than what is currently being used clinically and in research publications. Prolonged refrigerated storage of cosyntropin solution does not affect the validity of the 1 ?g cosyntropin test. PMID:23961488

Anantharaman, R.; Menezes, Geraldine; Yusuf, Razif; Ganapathi, B.; Ayyar, S. Vageesh; Srinivasan, R.

2013-01-01

214

Astronaut adaptation to 1 G following long duration space flight  

NASA Technical Reports Server (NTRS)

The paper reviews the results of studies of changes undergone by several physiological systems (including the cardiovascular system, the fluid and electrolyte characteristics, the red blood cells, the bone and the muscle tissues, and the exercise capacity) due to the exposures to microgravity and to the adaptation to 1 G after a long-duration space flight. Special attention is given to the effects of various training protocols and countermeasures used to attenuate the physiological problems encountered upon return from space.

Walker, John; Greenisen, Michael; Cowell, Lynda L.; Squires, William G.

1991-01-01

215

Preliminary characterisation of new glass reference materials (GSA-1G, GSC-1G, GSD-1G and GSE-1G) by laser ablation-inductively coupled plasma-mass spectrometry using 193 nm, 213 nm and 266 nm wavelengths  

USGS Publications Warehouse

New glass reference materials GSA-1G, GSC-1G, GSD-1G and GSE-1G have been characterised using a prototype solid state laser ablation system capable of producing wavelengths of 193 nm, 213 nm and 266 nm. This system allowed comparison of the effects of different laser wavelengths under nearly identical ablation and ICP operating conditions. The wavelengths 213 nm and 266 nm were also used at higher energy densities to evaluate the influence of energy density on quantitative analysis. In addition, the glass reference materials were analysed using commercially available 266 nm Nd:YAG and 193 nm ArF excimer lasers. Laser ablation analysis was carried out using both single spot and scanning mode ablation. Using laser ablation ICP-MS, concentrations of fifty-eight elements were determined with external calibration to the NIST SRM 610 glass reference material. Instead of applying the more common internal standardisation procedure, the total concentration of all element oxide concentrations was normalised to 100%. Major element concentrations were compared with those determined by electron microprobe. In addition to NIST SRM 610 for external calibration, USGS BCR-2G was used as a more closely matrix-matched reference material in order to compare the effect of matrix-matched and non matrix-matched calibration on quantitative analysis. The results show that the various laser wavelengths and energy densities applied produced similar results, with the exception of scanning mode ablation at 266 nm without matrix-matched calibration where deviations up to 60% from the average were found. However, results acquired using a scanning mode with a matrix-matched calibration agreed with results obtained by spot analysis. The increased abundance of large particles produced when using a scanning ablation mode with NIST SRM 610, is responsible for elemental fractionation effects caused by incomplete vaporisation of large particles in the ICP.

Guillong, M.; Hametner, K.; Reusser, E.; Wilson, S.A.; Gunther, D.

2005-01-01

216

Synthesis of Magnesium Diboride Wires  

NASA Astrophysics Data System (ADS)

Magnesium diboride, MgB2, has been of great interest recently due to its high superconducting transition temperature for a material which exhibits properties similar to classical (BCS) superconductors. It has been found that wire segments of MgB2 can be prepared by exposing commercial boron coated filaments to magnesium vapor. This research has shown that the critical current of such wires is highly dependent on the preparation procedures and wire properties. These cm long wire segments have a grain size ranging from 2-20 µm and will carry current densities of 20,000 A/cm2 at 20 K and 1 Tesla.

Canfield, Paul; Bud'Ko, Sergei; Finnemore Anderson, Douglas, Jr.

2002-03-01

217

System Identification of Wire Electrical Discharge Machining  

Microsoft Academic Search

In wire electrical discharge machining (wire-EDM), it is very important to restrain the vibration of the tool wire electrode for the improvement of machining accuracy. In this paper, investigation is carried out toward the dynamic wire vibration mechanism and a mathematical model is derived. This model is compared with experimental results. The measured displacement of a wire electrode in machining

N. Mohri; H. Yamada; K. Furutani; T. Narikiyo; T. Magara

1998-01-01

218

Thermal Insulation Performance of Flexible Piping for Use in HTS Power Cables  

NASA Technical Reports Server (NTRS)

High-temperature superconducting (HTS) cables that typically operate at temperatures below 80 K are being developed for power transmission. The practical application of HTS power cables will require the use of flexible piping to contain the cable and the liquid nitrogen coolant. A study of thermal performance of multilayer insulation (MLI) was conducted in geometries representing both rigid and flexible piping. This experimental study performed at the Cryogenics Test Laboratory of NASA Kennedy Space Center provides a framework for the development of cost-effective, efficient thermal insulation systems that will support these long-distance flexible lines containing HTS power cables. The overall thermal performance of the insulation system for a rigid configuration and for a flexible configuration, simulating a flexible HTS power cable, was determined by the steady-state liquid nitrogen boiloff method under the full range of vacuum levels. Two different cylindrically rolled material systems were tested: a standard MLI and a layered composite insulation (LCI). Comparisons of ideal MLI, MLI on rigid piping, and MLI between flexible piping are presented.

Fesmire, James E.; Augustynowicz, S. D.; Demko, J. A.; Thompson, Karen (Technical Monitor)

2001-01-01

219

SOFTWARE Open Access The HTS barcode checker pipeline, a tool for  

E-print Network

SOFTWARE Open Access The HTS barcode checker pipeline, a tool for automated detection of illegally-throughput sequencing of DNA barcoding markers obtained from such samples provides insight into species constituents DNA barcodes against NCBI GenBank using BLAST may yield misleading results both as false positives

Kaski, Samuel

220

Peculiarities on voltage - current characteristics of HTS tapes at overloading conditions cooled by liquid nitrogen  

Microsoft Academic Search

Electro - technical devices are considered as the most prospective use for high temperature superconductors. For such devices the overload currents due to faults in grids are the operational reality. In these cases the fault currents may forcibly go to superconductors being sometimes dozens times more than the critical currents of HTS. Overloads are the working modes for fault current

V S Vysotsky; S S Fetisov; V E Sytnikov

2008-01-01

221

Development of an HTS assay for EPHX2 phosphatase activity and screening of nontargeted libraries  

E-print Network

Development of an HTS assay for EPHX2 phosphatase activity and screening of nontargeted librariesPhos as the substrate. This assay was used to screen a wide variety of chemical entities, includ- ing a library of known drugs that have reached through clinical evaluation (Pharmakon 1600), as well as a library of pesticides

Hammock, Bruce D.

222

Predictive Signatures of Developmental Toxicity Modeled with HTS Data from ToxCast? Bioactivity Profiles  

EPA Science Inventory

The EPA ToxCast? research program uses a high-throughput screening (HTS) approach for predicting the toxicity of large numbers of chemicals. Phase-I contains 309 well-characterized chemicals which are mostly pesticides tested in over 600 assays of different molecular targets, cel...

223

Liquid air as a coolant for thermal management of long-length HTS cable systems  

NASA Astrophysics Data System (ADS)

Direct current (dc), high temperature superconducting (HTS) cable systems have been suggested as an effective method of transmitting very large amounts of electric power (up to 10 GW) over very long distances (thousands of kilometers). This is made possible mainly by the high-current-carrying capability of the HTS materials when operated below their critical temperatures and by their near zero resistance to constant current. Most HTS cable concepts rely on liquid nitrogen or gaseous helium as the coolant. As an alternative, liquid air offers certain benefits and is discussed here as a cable system coolant. Air has a lower freezing temperature than nitrogen, it can be produced locally, and a liquid air leak will not displace the oxygen in a closed compartment. The dc cable design concept proposed by the Electric Power Research Institute (EPRI) in which the coolant flows in a cryogenic enclosure that includes the cable and a separate return tube, and refrigeration stations positioned every 10 to 20 km is assumed for this analysis. Both go and return lines are contained in a single vacuum envelope. The thermal management of this superconducting cable concept with liquid air in long-distance HTS power cables is developed in this paper. The results are compared to the use of liquid nitrogen, gaseous helium and gaseous hydrogen.

Demko, Jonathan; Hassenzahl, William

2012-06-01

224

Industrial Fe-Ni alloys for HTS coated conductor tapes JL Soubeyroux1  

E-print Network

Industrial Fe-Ni alloys for HTS coated conductor tapes JL Soubeyroux1 , P Chaudouet2 , A Girard1, 38042 Grenoble, France, 2 LMGP/ Minatec/ Grenoble, France, 3 Imphy Alloys, Imphy, France jean and stabilized between 1050°C to 1100°C, depending on the nickel content of the alloy, higher temperature

Paris-Sud XI, Université de

225

Assessment of High Temperature Superconducting (HTS) electric motors for rotorcraft propulsion  

NASA Technical Reports Server (NTRS)

The successful development of high temperature superconductors (HTS) could have a major impact on future aeronautical propulsion and aeronautical flight vehicle systems. Applications of high temperature superconductors have been envisioned for several classes of aeronautical systems, including subsonic and supersonic transports, hypersonic aircraft, V/STOL aircraft, rotorcraft and solar powered aircraft. The potential of HTS electric motors and generators for providing primary shaft power for rotorcraft propulsion is examined. Three different sized production helicopters were investigated; namely, the Bell Jet Ranger, the Sikorsky Black Hawk and the Sikorsky Super Stallion. These rotorcraft have nominal horsepower ratings of 500, 3600, and 13400 respectively. Preliminary results indicated that an all-electric HTS drive system produces an improvement in rotorcraft Takeoff Gross Weight (TOGW) for those rotorcraft with power ratings above 2000 horsepower. The predicted TOGW improvements are up to 9 percent for the medium-sized Sikorsky Black Hawk and up to 20 percent for the large-sized Sikorsky Super Stallion. The small-sized Bell Jet Ranger, however, experienced a penalty in TOGW with the all-electric HTS drive system.

Doernbach, Jay

1990-01-01

226

Monitoring of HTS Compound Library Quality via a High-Resolution Image Acquisition and Processing Instrument  

PubMed Central

This report presents the high-resolution image acquisition and processing instrument for compound management applications (HIAPI-CM). The HIAPI-CM combines imaging spectroscopy and machine vision analysis to perform rapid assessment of HTS compound library quality. It has been customized to detect and classify typical artifacts found in HTS compound library microtiter plates (MTPs). These artifacts include: (a) insufficient volume of liquid compound sample, (b) compound precipitation, and (c) colored compounds that interfere with HTS assay detection format readout. The HIAPI-CM is also configured to automatically query & compare its analysis results to data stored in a LIMS or corporate database, aiding in the detection of compound registration errors. To demonstrate its capabilities, several compound plates (n =5760 wells total) containing different artifacts were measured via automated HIAPI-CM analysis, and results compared to those obtained by manual (visual) inspection. In all cases, the instrument demonstrated high fidelity (99.8% empty wells; 100.1% filled wells; 94.4% for partially filled wells; 94.0% for wells containing colored compounds), and in the case of precipitate detection, the HIAPI-CM results significantly exceeded the fidelity of visual observations (220.0%). As described, the HIAPI-CM allows for noninvasive, nondestructive MTP assessment with a diagnostic throughput of about one minute per plate, reducing analytical expenses and improving the quality and stewardship of HTS compound libraries. PMID:21609702

Baillargeon, Pierre; Scampavia, Louis; Einsteder, Ross

2011-01-01

227

A 4m 2kA HTS Power Cable System  

Microsoft Academic Search

A high temperature superconductor (HTS) cable system of both a length of 4 metre and a normal current of 2 KA with terminations and a cooling system has been built up and tested. The cable conductor was made of Bi-2223 tape. A space maintained vacuum between two corrugated stainless steel tubes functions as the cryostat surrounding the superconductor. A series

Bo Hou; Yanfang Bi; Songtao Wu; Haixia Xi; Feng Yuan; Ying Xin; Yong Zhang; Huaikuang Ding; Jing Shi; Jinsong Zhang

2006-01-01

228

Nanomaterial (NM) bioactivity profiling by ToxCast high-throughput screening (HTS)  

EPA Science Inventory

Rapidly increasing numbers of new NMs and their uses demand efficient tests of NM bioactivity for safety assessment. The EPA?s ToxCast program uses HTS assays to prioritize for targeted testing, identify biological pathways affected, and aid in linking NM properties and potential...

229

Basic concepts, status, opportunities, and challenges of electrical machines utilizing high-temperature superconducting (HTS) windings  

NASA Astrophysics Data System (ADS)

An overview of the different approaches towards achieving a marketable application of a superconducting electrical machine, either as synchronous motor or generator, will be given. This field ranges from relatively small industrial drives to utility generators with large power ratings, from the low speed and high torque of wind power generators and ship propulsion motors, to high speed generators attached to turbines. Essentially HTS machine technology offers several advantages such as compactness (weight and volume reduction), increased efficiency, and other operational benefits. The machine features have to be optimized with regard to the specific application, and different concepts were developed by internationally competing teams, with Siemens being one of them. The achieved status in these fields will be summarized, pointing to the specific technical challenges to overcome. For this purpose we have not only to consider the technology of manufacturing the HTS rotor winding itself, but also to check requirements and availability of supporting technologies. This ranges from new challenges posed to the non-superconducting ("conventional") components of such innovative HTS machines, manufacturing superconducting material in the coming transition from 1st to 2nd generation HTS tape, cryogenic technology including material behavior, to new and challenging tasks in simulating and predicting the performance of such machines by computational tools. The question of market opportunities for this technology obviously is a function of all these aspects; however, a strong tendency for the near future is seen in the area of high-torque ship propulsion.

Frauenhofer, J.; Grundmann, J.; Klaus, G.; Nick, W.

2008-02-01

230

A Cool-down and Fault Study of a Long Length HTS Power Transmission Cable  

Microsoft Academic Search

High temperature superconductor (HTS) power transmission cables offer significant advantages in power density over conventional copper-based cables. Currently the US Department of Energy is funding the design, development, and demonstration of the first long length, transmission level voltage, cold dielectric, underground high temperature superconductor power cable. The cable is 620 meters long and is designed for permanent installation in the

J. Yuan; J. Maguire; A. Allais; F. Schmidt

2006-01-01

231

The Nitrogen Boil-Off Method for Measuring AC Losses in HTS Coils  

Microsoft Academic Search

We have developed a novel apparatus for applying a nitrogen boil-off method as a mean of making calorimetric measurements and allowing for simple measuring and evaluating of AC losses in HTS coils at liquid nitrogen temperature. With the ability to measure AC loss generated in superconductors directly, this method produces more reliable data than that obtained by general, electro-magnetic measurements.

H. Okamoto; F. Sumiyoshi; K. Miyoshi; Y. Suzuki

2006-01-01

232

Pathway Profiling and Tissue Modeling Using ToxCast HTS Data  

EPA Science Inventory

High-throughput screening (HTS) and high-content screening (HCS) assays are providing data-rich studies to probe and profile the direct cellular effects of thousands of chemical compounds in commerce or potentially entering the environment. In vitro profiling may compare unknown ...

233

Composite Wires with High Tensile Core for Wire EDM  

Microsoft Academic Search

In recent years wire EDM cutting speeds and final surface roughness have been continuously improving. Much higher cutting speeds during roughing and surface roughness values lower than 0.1 ?m Ra during finishing can be obtained. These enhancements are mostly attributed to the use of more advanced generator technology, but also to the type of wire. This paper discusses the use

J.-P. Kruth; B. Lauwers; B. Schacht; J. van Humbeeck

2004-01-01

234

Characteristics of trapped magnetic fields in HTS bulk annuli with various axial spaces for compact NMR magnets  

NASA Astrophysics Data System (ADS)

Recently, the performance of high-temperature superconducting (HTS) bulks such as a critical current density, size, and mechanical strength has been improved. In consequence, various applications with HTS bulks such as motors, bearings, and flywheels are being investigated by many research groups; Compact nuclear magnetic resonance (NMR) magnet is one of the new applications after a technique to enhance maximum trapped field of an HTS bulk more than 11.7 T, 500 MHz 1H NMR frequency, has been developed. This new compact NMR magnet out of HTS bulks is far less expensive than those conventional NMR magnets and expected to be widely used in food and drug industry. In design and manufacture of those compact NMR magnets, the issues of spatial homogeneity and temporal stability of trapped magnetic fields in HTS bulk annuli are very important. In this paper, the characteristics of the trapped magnetic fields in a stack of assembled HTS bulk annuli were investigated with various axial spaces between HTS bulks, experimentally and analytically.

Kim, S. B.; Imai, M.; Takano, R.; Kashima, K.; Hahn, S.

2010-11-01

235

Soft magnetic wires  

NASA Astrophysics Data System (ADS)

An overview of the present state of the art on the preparation techniques, outstanding magnetic properties and applications of soft magnetic micro and nanowires is presented. Rapid solidification techniques (in-rotating-water quenching and drawing methods) to fabricate amorphous microwires with diameter in the range from 100 down to 1 ?m are first described. Electrodeposition is also employed to prepare composite microtubes (magnetic coatings) and to fill porous membranes (diameter of the order of 0.1 ?m). Magnetic behaviours of interest are related to the different hysteresis loops of samples: square-shaped loops typical of bistable behaviour, and nearly non-hysteretic loop with well-defined transverse anisotropy field. The role played by magnetic dipolar interactions in the magnetic behaviour of arrays of micro and nanowires is described. A particular analysis is done on the giant magnetoimpedance (GMI) effect in the radio and microwave frequency ranges exhibited by ultrasoft microwires. Finally, a few examples of applications are introduced for magnetostrictive and non-magnetostrictive wires, they are: “magnetoelastic pens”, micromotors; DC current-sensors based on GMI, and sharpened amorphous wire tips in spin polarised scanning tunneling microscopy.

Vázquez, M.

2001-06-01

236

Asteroseismology "on a WIRE"  

NASA Astrophysics Data System (ADS)

The Wide-field Infra Red Explorer (WIRE) was launched in March 1999. Its main mission failed due to loss of coolant, but the 52 mm aperture star camera was used for asteroseismology. A few results are already published, but other bright variable stars were observed as well. Here we present an overview of the preliminary results and detailed period analyses on WIRE data of massive main-sequence pulsators. The period of the ? Scuti star ? Cas could be easily recovered. In an almost uninterrupted observing run of 17 days on the 16 Msolar star ? Crucis (Mimosa) multiperiodicity could be found in the light variations of this ? Cephei variable. Ground-based photometry so far revealed only one period for this star. Although the amplitudes are small (3, 2.7 and 0.6 millimag for the dominant modes), the periods are in perfect agreement with the results of a recent line profile study of this star. Indications of more periods, including a previously suggested one, are present. The results obtained during this unintentional and unadapted asteroseismology project are extremely promising. They show only a tiny fraction of the outcome of a fully adapted asteroseismological mission like Eddington.

Cuypers, J.; Aerts, C.; Buzasi, D.; Catanzarite, J.; Conrow, T.; Laher, R.

2002-01-01

237

Improved superconducting magnet wire  

DOEpatents

This invention is directed to a superconducting tape or wire composed of alternating layers of copper and a niobium-containing superconductor such as niobium of NbTi, Nb/sub 3/Sn or Nb/sub 3/Ge. In general, each layer of the niobium-containing superconductor has a thickness in the range of about 0.05 to 1.5 times its coherence length (which for Nb/sub 3/Si is 41 A) with each copper layer having a thickness in the range of about 170 to 600 A. With the use of very thin layers of the niobium composition having a thickness within the desired range, the critical field (H/sub c/) may be increased by factors of 2 to 4. Also, the thin layers of the superconductor permit the resulting tape or wire to exhibit suitable ductility for winding on a magnet core. These compositions are also characterized by relatively high values of critical temperature and therefore will exhibit a combination of useful properties as superconductors.

Schuller, I.K.; Ketterson, J.B.

1983-08-16

238

Electric field analysis on the insulation design of the stop joint box for DC HTS power cable  

NASA Astrophysics Data System (ADS)

DC HTS power cable is a promising electric power transmission line for the future of smart grid, and it has been competitively investigated at many research institutes all over the world. For the commercialization of DC HTS cable, higher power transmission capacity and longer length for long distance transmission line should be prepared. In order to meet the needs of long distance DC HTS cable, a joint box should be developed for the connection of cable components. As for AC HTS cable, a number of patents of nominal joint box have been already reported. However, any conceptual designs of the joint box for DC HTS cable have not been suggested yet. One of the reasons is that the cryogenic high voltage insulation design, especially in DC environment is not fully investigated yet. Conventional normal joint box for AC HTS cable could not be directly applied to DC HTS cable because different electric field distributions compared to AC electric field which requires totally different electrical insulation design concepts. In this paper, in order to establish the basic insulation design of the stop joint box (SJB) for DC HTS cable, three kinds of SJB models were designed and electric field analyses have been conducted both considering AC and DC environment. And the critical factors affecting the DC insulation design of the stop joint box were analyzed. From the simulation results, it was observed that the electric field distribution was totally different both in AC and DC operating conditions. And it was possible to find the weakest regions in the insulation design of the SJB. Consequently, based on the DC electric field analysis, the insulation design criteria and the desirable configurations were suggested for the insulation design of the stop joint box for DC HTS cable.

Hwang, Jae-Sang; Ryoo, Hee-Suk; Koo, Ja-Yoon; Cho, Jeon-Wook; Lee, Bang-Wook

2014-09-01

239

An active homopolar magnetic bearing with high temperature superconductor (HTS) coils and ferromagnetic cores  

NASA Technical Reports Server (NTRS)

A proof-of-feasibility demonstration showed that high temperature superconductor (HTS) coils can be used in a high-load, active magnetic bearing in liquid nitrogen. A homopolar radial bearing with commercially wound HTS (Bi 2223) bias and control coils produced over 200 lb (890 N) radial load capacity (measured non-rotating) and supported a shaft to 14000 rpm. The goal was to show that HTS coils can operate stably with ferromagnetic cores in a feedback controlled system at a current density similar to that in Cu in liquid nitrogen. Design compromises permitted use of circular coils with rectangular cross section. Conductor improvements will eventually permit coil shape optimization, higher current density and higher bearing load capacity. The bias coil, wound with non-twisted, multifilament HTS conductor, required negligible power to carry its direct current. The control coils were wound with monofilament HTS sheathed in Ag. These dissipated negligible power for direct current (i.e. for steady radial load components). When an alternating current (AC) was added, the AC component dissipated power which increased rapidly with frequency and quadratically with AC amplitude. In fact at frequencies above about 2 hz, the effective resistance of the control coil conductor actually exceeds that of the silver which is in electrical parallel with the oxide superconductor. This is at least qualitatively understandable in the context of a Bean-type model of flux and current penetration into a Type II superconductor. Fortunately the dynamic currents required for bearing stability are of small amplitude. These results show that while twisted multifilament conductor is not needed for stable levitation, twisted multifilaments will be required to reduce control power for sizable dynamic loads, such as those due to unbalance.

Brown, G. V.; Dirusso, E.; Provenza, A. J.

1995-01-01

240

Joint analysis of the Cs2 a^3? _u^+ and 1g (33?1g) states  

NASA Astrophysics Data System (ADS)

Sets of experimental data on the Cs2 a^3? _u^+ and 1g (33?1g) states, including the bound-bound and bound-free fluorescence spectra, are analyzed simultaneously to produce the potential energy curves of both states in the form of the Morse long range multiparameter function. The attractive branch of the a^3? _u^+ state potential is improved relative to the one reported in our earlier work [F. Xie, V. B. Sovkov, A. M. Lyyra, D. Li, S. Ingram, J. Bai, V. S. Ivanov, S. Magnier, and L. Li, J. Chem. Phys. 130, 051102 (2009)], 10.1063/1.3075580, in which the data on this state alone were analyzed. Besides, the new potential of this state also includes the repulsive branch in the range spanned by the bound-free fluorescence spectra. We have not found experimental evidence of the double minimum character of the 33?1g state potential, predicted by ab initio calculations, at least up to v = 8. This fact testifies that the upper state observed is better described by the Hund coupling case (c), in which the case (a) electronic basis states are intermixed by the strong spin-orbit interaction.

Xie, F.; Li, Li; Li, D.; Sovkov, V. B.; Minaev, K. V.; Ivanov, V. S.; Lyyra, A. M.; Magnier, S.

2011-07-01

241

Northern Pacific Railroad Bridge and Wire Weight  

USGS Multimedia Gallery

Wire weight is lowered to water surface to measure stage at a site. Levels are made to the wire weights elevation from known benchmarks to ensure correct readings. This wire weight is located along the Missouri River in Bismarck, ND....

242

Aircraft wiring program status report  

NASA Astrophysics Data System (ADS)

In this Naval Air Warfare Center (NAWC) Aircraft Division status report, the general and wire and cable component activities, the systems engineering activities, the aircraft wiring lead maintenance activities, the NAVAIR/NASA interface activities, and the Base Realignment and Closure (BRAC) Commission recommendations are presented.

Beach, Rex

1995-11-01

243

Most Wired 2006: measuring value.  

PubMed

As the Most Wired hospitals incorporate information technology into their strategic plans, they combine a"balanced scorecard"approach with classic business analytics to measure how well IT delivers on their goals. To find out which organizations made this year's 100 Most Wired list, as well as those named in other survey categories, go to the foldout section. PMID:16915970

Solovy, Alden

2006-07-01

244

Straddle packer wire line tester  

Microsoft Academic Search

This invention proposes to overcome the shortcomings of previous fluid recovering wire-line testers, by setting forth a novel construction for a wire-line testing tool. The tool is suspended from the wellhead by a multistrand insulated electrical cable similar to that used to run electrical logs, and utilizes a straddle packer arrangement to isolate a portion of well bore. The packers

1967-01-01

245

The Current in a Wire  

ERIC Educational Resources Information Center

This little problem arose because I was frustrated with the standard electromagnetism texts, which show the magnetic field due to a current-bearing wire outside the wire [proportional to] 1/r and inside [proportional to] r. However, they never point out that the moving electrons must be influenced by the magnetic field created by the other moving…

Thompson, Keith

2009-01-01

246

Electrode carrying wire for GTAW welding  

NASA Technical Reports Server (NTRS)

A welding torch for gas tungsten arc welding apparatus has a hollow tungsten electrode including a ceramic liner and forms the filler metal wire guide. The wire is fed through the tungsten electrode thereby reducing the size of the torch to eliminate clearance problems which exist with external wire guides. Since the wire is preheated from the tungsten more wire may be fed into the weld puddle, and the wire will not oxidize because it is always within the shielding gas.

Morgan, Gene E. (inventor); Dyer, Gerald E. (inventor)

1990-01-01

247

Internal wire guide for GTAW welding  

NASA Technical Reports Server (NTRS)

A welding torch for gas tungsten arc welding apparatus has a filler metal wire guide positioned within the torch, and within the shielding gas nozzle. The wire guide is adjacent to the tungsten electrode and has a ceramic liner through which the wire is fed. This reduces the size of the torch and eliminates the outside clearance problems that exit with external wire guides. Additionally, since the wire is always within the shielding gas, oxidizing of the wire is eliminated.

Morgan, Gene E. (inventor); Dyer, Gerald E. (inventor)

1989-01-01

248

Apollo experience report: Electrical wiring subsystem  

NASA Technical Reports Server (NTRS)

The general requirements of the electrical wiring subsystems and the problem areas and solutions that occurred during the major part of the Apollo Program are detailed in this report. The concepts and definitions of specific requirements for electrical wiring; wire-connecting devices; and wire-harness fabrication, checkout, and installation techniques are discussed. The design and development of electrical wiring and wire-connecting devices are described. Mission performance is discussed, and conclusions and recommendations for future programs are presented.

White, L. D.

1975-01-01

249

Nano-storage wires.  

PubMed

We report the development of "nano-storage wires" (NSWs), which can store chemical species and release them at a desired moment via external electrical stimuli. Here, using the electrodeposition process through an anodized aluminum oxide template, we fabricated multisegmented nanowires composed of a polypyrrole segment containing adenosine triphosphate (ATP) molecules, a ferromagnetic nickel segment, and a conductive gold segment. Upon the application of a negative bias voltage, the NSWs released ATP molecules for the control of motor protein activities. Furthermore, NSWs can be printed onto various substrates including flexible or three-dimensional structured substrates by direct writing or magnetic manipulation strategies to build versatile chemical storage devices. Since our strategy provides a means to store and release chemical species in a controlled manner, it should open up various applications such as drug delivery systems and biochips for the controlled release of chemicals. PMID:23859333

Lee, Dong Jun; Kim, Eunji; Kim, Daesan; Park, Juhun; Hong, Seunghun

2013-08-27

250

Engineering nanocolumnar defect configurations for optimized vortex pinning in high temperature superconducting nanocomposite wires  

PubMed Central

We report microstructural design via control of BaZrO3 (BZO) defect density in high temperature superconducting (HTS) wires based on epitaxial YBa2Cu3O7-? (YBCO) films to achieve the highest critical current density, Jc, at different fields, H. We find the occurrence of Jc(H) cross-over between the films with 1–4?vol% BZO, indicating that optimal BZO doping is strongly field-dependent. The matching fields, B?, estimated by the number density of BZO nanocolumns are matched to the field ranges for which 1–4?vol% BZO-doped films exhibit the highest Jc(H). With incorporation of BZO defects with the controlled density, we fabricate 4-?m-thick single layer, YBCO + BZO nanocomposite film having the critical current (Ic) of ~1000?A cm?1 at 77?K, self-field and the record minimum Ic, Ic(min), of 455?A cm?1 at 65?K and 3?T for all field angles. This Ic(min) is the largest value ever reported from HTS films fabricated on metallic templates. PMID:23939231

Wee, Sung Hun; Zuev, Yuri L.; Cantoni, Claudia; Goyal, Amit

2013-01-01

251

An approach for electrical self-stabilization of high-temperature superconducting wires for power applications  

NASA Astrophysics Data System (ADS)

Electrical and thermal stability of high-temperature superconducting (HTS) wires/tapes are essential in applications involving efficient production, distribution, and storage of electrical energy. We have developed a conductive buffer layer structure composed of bilayer La0.7Sr0.3MnO3/Ir on a textured Ni -W alloy metal tape to functionally shunt the HTS layer to the underlying substrate. The key feature is the Ir layer, which serves as a barrier to both inward diffusion of oxygen and outward diffusion of metal substrate cations during fabrication. Electrical and microstructural property characterizations of YBa2Cu3O7-? films on short prototype conductors demonstrate self-field critical current density values, Jc, exceeding 2×106A /cm2 at 77K and excellent electrical coupling to the underlying metal substrate, with no unwanted insulating oxide interfaces. Implementing this approach in power technologies would significantly increase the engineering current density of the conductor and reduce overall process costs.

Aytug, T.; Paranthaman, M.; Zhai, H. Y.; Gapud, A. A.; Leonard, K. J.; Martin, P. M.; Goyal, A.; Thompson, J. R.; Christen, D. K.

2004-10-01

252

Identification and characterization of the heme-binding proteins SeShp and SeHtsA of Streptococcus equi subspecies equi  

PubMed Central

Background Heme is a preferred iron source of bacterial pathogens. Streptococcus equi subspecies equi is a bacterial pathogen that causes strangles in horses. Whether S. equi has a heme acquisition transporter is unknown. Results An S. equi genome database was blasted with the heme binding proteins Shp and HtsA of Streptococcus pyogenes, and found that S. equi has the homologue of Shp (designated SeShp) and HtsA (designated SeHtsA). Tag-free recombinant SeShp and SeHtsA and 6xHis-tagged SeHtsA (SeHtsAHis) were prepared and characterized. Purified holoSeShp and holoSeHtsA bind Fe(II)-protoporphyrin IX (heme) and Fe(III)-protoporphyrin IX (hemin) in a 1:1 stoichiometry, respectively, and are designated hemoSeShp and hemiSeHtsA. HemiSeShp and hemiSeHtsAHis can be reconstituted from apoSeShp and apoSeHtsAHis and hemin. HemoSeShp is stable in air and can be oxidized to hemiSeShp by ferricyanide. HemiSeHtsA can be reduced into hemoSeHtsA, which autoxidizes readily. HemoSeShp rapidly transfers its heme to apoSeHtsAHis. In addition, hemoSeShp can also transfer its heme to apoHtsA, and hemoShp is able to donate heme to apoSeHtsAHis. Conclusion The primary structures, optical properties, oxidative stability, and in vitro heme transfer reaction of SeShp and SeHtsA are very similar to those of S. pyogenes Shp and HtsA. The data suggest that the putative cell surface protein SeShp and lipoprotein SeHtsA are part of the machinery to acquire heme in S. equi. The results also imply that the structure, function, and functional mechanism of the heme acquisition machinery are conserved in S. equi and S. pyogenes. PMID:17007644

Nygaard, Tyler K; Liu, Mengyao; McClure, Michael J; Lei, Benfang

2006-01-01

253

Performance Evaluation of The Speaker-Independent HMM-based Speech Synthesis System "HTS-2007" for the Blizzard Challenge 2007   

E-print Network

This paper describes a speaker-independent/adaptive HMM-based speech synthesis system developed for the Blizzard Challenge 2007. The new system, named HTS-2007, employs speaker adaptation (CSMAPLR+MAP), feature-space adaptive training, mixed...

Yamagishi, Junichi; Tokuda, Keiichi; Toda, Tomoki; Heiga, Zen; Nose, Takashi

2008-01-01

254

Plasma chemistry in wire chambers  

SciTech Connect

The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an {sup 55}Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed.

Wise, J.

1990-05-01

255

Proton irradiation effects on critical current of bulk single-crystal superconducting YBCO wire  

SciTech Connect

The authors have investigated the effects of 10 MeV proton irradiation on the magnetization M and critical current density J{sub c} of bulk single-crystal YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) superconducting thick wire filaments produced through laser-heated floating zone (LHFZ) technique. M and J{sub c} were determined both along the length and perpendicular to the length of the wire. Radiation-induced enhancement of J{sub c} along the length of the wire was observed while there was a small decrease in J{sub c} {perpendicular} to its length. J{sub c} values along the length of the wire up to {approximately}1.4 {times} 10{sup 5} A/cm{sup 2} at 77K and {approximately}1.3 {times} 10{sup 6} A/cm{sup 2} at 30K and in applied magnetic field H = 1 T were observed in the irradiated samples. In the unirradiated sample, the difference in magnetization {Delta}M at a given field in the magnetic hysteresis loop for increasing and decreasing field applied {perpendicular} to the sample length was observed to depend on the orientation of the sample about its axis. This indicates anisotropy in J{sub c} along the sample length. This anisotropy increased on irradiation relative to the direction of irradiation. They believe that these J{sub c} values along the length are amongst the highest published J{sub c} values for bulk high temperature superconductor (HTS) thick wire filament.

Khanna, S.M. [Defence Research Establishment Ottawa, Ontario (Canada)] [Defence Research Establishment Ottawa, Ontario (Canada); Figueredo, A.M. [National Research Council, Boucherville, Quebec (Canada). Industrial Materials Inst.] [National Research Council, Boucherville, Quebec (Canada). Industrial Materials Inst.

1997-12-01

256

The levitation characteristics of the magnetic substances using trapped HTS bulk annuli with various magnetic field distributions  

NASA Astrophysics Data System (ADS)

We have been investigating the levitation system without any mechanical contact which is composed of a field-cooled ring-shaped high temperature superconducting (HTS) bulks [1]. In this proposed levitation system, the trapped magnetic field distributions of stacked HTS bulk are very important. In this paper, the spherical solenoid magnet composed of seven solenoid coils with different inner and outer diameters was designed and fabricated as a new magnetic source. The fabricated spherical solenoid magnet can easily make a homogeneous and various magnetic field distributions in inner space of stacked HTS bulk annuli by controlling the emerging currents of each coil. By using this spherical solenoid magnet, we tried to make a large magnetic field gradient in inner space of HTS bulk annuli, and it is very important on the levitation of magnetic substances. In order to improve the levitation properties of magnetic substances with various sizes, the external fields were reapplied to the initially trapped HTS bulk magnets. We could generate a large magnetic field gradient along the axial direction in inner space of HTS bulk annuli, and obtain the improved levitation height of samples by the proposed reapplied field method.

Kim, S. B.; Ikegami, T.; Matsunaga, J.; Fujii, Y.; Onodera, H.

2013-11-01

257

A wide stopband band-pass HTS filter with staggered resonators  

NASA Astrophysics Data System (ADS)

This letter presents a novel high-temperature superconducting (HTS) band-pass filter with a very wide stopband using the method of staggered resonant modes, that is, dissimilar resonators with the same fundamental frequency but different harmonic frequencies. A new type of resonator that is suitable for this method is proposed. The design rules and design process of this method are analyzed in detail. A six-pole HTS band-pass filter centered at 500 MHz with a 2 MHz bandwidth is successfully designed and fabricated. Measured out-of-band rejection is better than 60 dB and can reach up to 13 GHz, which is about 26 times the fundamental frequency.

Wang, Jingchen; Wei, Bin; Cao, Bisong; Guo, Xubo; Zhang, Xiaoping; Song, Xiaoke

2013-12-01

258

A compact HTS bandpass microstrip filter with novel coupling structure for on-chip integration  

NASA Astrophysics Data System (ADS)

A compact low-complexity high-selectivity high-temperature superconducting (HTS) microstrip bandpass filter is presented in this paper, which consists of only three half-wavelength resonators. A novel coupling scheme is used to provide a pair of transmission zeros outside the passband, so that the selectivity of the filter is improved. The filter is fabricated on an MgO substrate with YBa2Cu3O7-x (YBCO) coating. Measurement result shows an in-band insertion loss at 0.5 dB, a sharp slope, and a stopband rejection better than 20 dB. The compactness and high-selectivity features make the filter suitable for on-chip integration of HTS receiver front-ends.

Zhang, Ting; Du, Jia; Guo, Yingjie Jay; Sun, Xiaowei

2013-12-01

259

Effect of corrugated characteristics on the liquid nitrogen temperature field of HTS cable  

NASA Astrophysics Data System (ADS)

In the high temperature superconducting (HTS) cable system, liquid nitrogen is usually chosen to be the coolant because of its low saturation temperature and large latent heat of vaporization. Thus, it is very important for superconducting cables that the liquid nitrogen temperature field keeps stable. However, the cryostat is usually made of flexible corrugated pipes and multi-layer insulation materials. The characteristics (e.g. wave pitch and wave depth) of corrugated pipes may have an effect on the heat exchange between cable and liquid nitrogen, even the whole temperature field of liquid nitrogen. In this paper, a two-dimensional model for 30 m long HTS cable has been modified to analyze the effect of corrugated characteristics on the temperature field of liquid nitrogen. The liquid nitrogen temperature difference between the outlet and the inlet of passage gradually increases as the wave pitch of the corrugated tube decreases and the wave depth increases.

Li, Z. M.; Li, Y. X.; Zhao, Y. Q.; Gao, C.; Qiu, M.; Chen, G. F.; Gong, M. Q.; Wu, J. F.

2014-01-01

260

Influence of Off-Centre Operation on the Performance of HTS Maglev  

NASA Astrophysics Data System (ADS)

Owing to instinctive self-stable levitation characteristics, high-temperature superconducting (HTS) maglev using bulk high-temperature superconductors attracts more and more attention from scientists and engineers around the world. In this paper, the levitation force relaxation and guidance force characteristics of a Y-Ba-Cu-O levitation unit with different eccentric distances (EDs) off the center of the permanent magnet guideway were experimentally investigated under field-cooling (FC) conditions. Experimental results indicate that the levitation force slightly increases at small EDs firstly, but degrades with further increasing of EDs. However, the maximum guidance force and its stiffness exhibit enhancement in moderate ED range. The results demonstrate that a properly designed initial FC eccentric distance is important for the practical applications of HTS maglev according to specific requirements like running in curve lines.

Gou, Y.; He, D.; Zheng, J.; Ye, C.; Xu, Y.; Sun, R.; Che, T.; Deng, Z.

2014-03-01

261

High temperature sol–gel insulation coatings for HTS magnets and their adhesion properties  

Microsoft Academic Search

This paper describes the adhesion properties of sol–gel insulation coatings with silver tape substrates using a mini-tensile-testing for HTS magnets. The sol–gel coatings were produced using solutions of Zr, Mg, Y, Ce, In and Sn based organometallic compounds. The growth mechanism of these coatings on Ag and AgMg sheathed Bi-2212 superconducting tapes was characterized by scanning electron microscopy, energy dispersive

E. Celik; E. Avci; Y. S. Hascicek

2000-01-01

262

Development of a coreless HTS synchronous generator operating at sub-cooled liquid nitrogen temperatures  

Microsoft Academic Search

This paper presents the current design concepts for a 100kW high temperature superconducting synchronous generator currently being designed at the University of Southampton, UK. The new generator will use the same conventional 2-pole 3-phase stator that was used in the HTS synchronous generator previously constructed at Southampton. The windings consist of 18 pancake coils made from BiPb2223 superconducting tape with

M K Al-Mosawi; W Bailey; C Beduz; K Goddard; Y Yang

2008-01-01

263

Introduction of China's first live grid installed HTS power cable system  

Microsoft Academic Search

China's first HTS power cable project was started in the second half of 2002 and on site system installation was finished at Puji Substation of China Southern Power Grid in March, 2004. This cable system consists of three 33.5 m, 35 kV\\/2 kArms cables, six terminations, and a closed cycle liquid nitrogen cooling station. The conductors of the cables were

Ying Xin; Bo Hou; Yanfang Bi; Haixia Xi; Yong Zhang; Anlin Ren; Xicheng Yang; Zhenghe Han; Songtao Wu; Huaikuang Ding

2005-01-01

264

Magnetic Field Distribution of Permanent Magnet Magnetized by Static Magnetic Field Generated by HTS Bulk Magnet  

Microsoft Academic Search

Demagnetized rare earth magnets (Nd-Fe-B) can be fully magnetized by scanning them in the intense static fields over 3 T of a HTS bulk magnet which was cooled to the temperature range lower than 77K with use of cryo-coolers and activated by the field of 5 T. We precisely examined the magnetic field distributions of magnetized permanent magnets. The magnetic

Tetsuo Oka; Nobutaka Kawasaki; Satoshi Fukui; Jun Ogawa; Takao Sato; Toshihisa Terasawa; Yoshitaka Itoh; Ryohei Yabuno

2012-01-01

265

Fundamental Design and Parameter Optimization Study of HTS Generatorsfor CoGeneration Systems  

Microsoft Academic Search

A fundamental design study of 0.45-6.0 MW retrofit HTS generators for co-generation systems, composed of Bi-2223 superconductor field windings at 30 K with a conventional stator, was carried out. The influence of generator parameters such as synchronous reactance and the rotor diameter on the generator weight, efficiency and superconductor volume was studied. Generator parameters were optimized considering the trade-offs between

Y. Nanao; N. Maki

2006-01-01

266

Demonstrating Forces between Parallel Wires.  

ERIC Educational Resources Information Center

Describes a physics demonstration that dramatically illustrates the mutual repulsion (attraction) between parallel conductors using insulated copper wire, wooden dowels, a high direct current power supply, electrical tape, and an overhead projector. (WRM)

Baker, Blane

2000-01-01

267

Optimization of a condensed-neon cooling system for a HTS synchronous motor with Gd-bulk HTS field-pole magnets  

NASA Astrophysics Data System (ADS)

The axial-gap synchronous machine developed in our laboratory is based on Gd-bulk HTS field-pole magnets, able to trap a part of the magnetic flux they are submitted to when cooled down below Tc. At the liquid nitrogen temperature, by the Pulsed-Field Magnetization (PFM), 1.04 T was trapped in 60 mm-diameter and 20 mm-thickness magnets, leading to an output power of the motor of 10 kW at 720 rpm. To enhance this performance, we have to increase the total amount of trapped flux in the bulk, the shortest way being to decrease the temperature of the bulk HTS. Thus, we focused on the improvement of the condensed-neon cooling system, a closed-cycle thermosyphon, so that it provided enough cooling power to lead the rotor plate enclosing the magnets to a low temperature. The present study implied coming out with a new fin-oriented design of the condensation chamber; hence, the numeric calculations and FEM software (ANSYS) heat transfer simulations were conducted for various shapes and positions of the fins. The trapezoidal design offering the best efficiency was then manufactured for testing in a heat-load test configuration, leading to cooling times divided by three and a maximum heat load endured of 55 W.

Felder, B.; Miki, M.; Tsuzuki, K.; Izumi, M.; Hayakawa, H.

2010-06-01

268

Passive radiative cooling of a HTS coil for attitude orbit control in micro-spacecraft  

NASA Astrophysics Data System (ADS)

This paper proposes a novel radiative cooling system for a high temperature superconducting (HTS) coil for an attitude orbit control system in nano- and micro-spacecraft missions. These days, nano-spacecraft (1-10 kg) and micro-spacecraft (10-100 kg) provide space access to a broader range of spacecraft developers and attract interest as space development applications. In planetary and high earth orbits, most previous standard-size spacecraft used thrusters for their attitude and orbit control, which are not available for nano- and micro-spacecraft missions because of the strict power consumption, space, and weight constraints. This paper considers orbit and attitude control methods that use a superconducting coil, which interacts with on-orbit space plasmas and creates a propulsion force. Because these spacecraft cannot use an active cooling system for the superconducting coil because of their mass and power consumption constraints, this paper proposes the utilization of a passive radiative cooling system, in which the superconducting coil is thermally connected to the 3 K cosmic background radiation of deep space, insulated from the heat generation using magnetic holders, and shielded from the sun. With this proposed cooling system, the HTS coil is cooled to 60 K in interplanetary orbits. Because the system does not use refrigerators for its cooling system, the spacecraft can achieve an HTS coil with low power consumption, small mass, and low cost.

Inamori, Takaya; Ozaki, Naoya; Saisutjarit, Phongsatorn; Ohsaki, Hiroyuki

2015-02-01

269

HTS-FCL EMTDC model considering nonlinear characteristics on fault current and temperature  

NASA Astrophysics Data System (ADS)

One of the most serious problems of the KEPCO system is a higher fault current than the CB(Circuit breaker's SCC (Short Circuit Capacity). There are so many alternatives to reduce the higher fault current, such as the isolation of bus ties, enhancement of the CB's SCC, and the application of HVDC-BTB (Back to Back) or FCL (fault current limiter). However, these alternatives have drawbacks from the viewpoint of system stability and cost. As superconductivity technology has been developed, the resistive type (R-type) HTS-FCL (High Temperature Superconductor Fault Current Limiter) offers one of the important alternatives in terms of power loss and cost reduction in solving the fault current problem. To evaluate the accurate transient performance of R-type HTS-FCL, it is necessary for the dynamic simulation model to consider transient characteristics during the quenching and the recovery state. Against this background, this paper presents the new HTS-FCL EMTDC (Electro-Magnetic Transients including Direct Current) model considering the nonlinear characteristics on fault current and temperature.

Yoon, Jae-Young; Lee, Seung-Ryul

2010-06-01

270

Design and development of 500 m long HTS cable system in the KEPCO power grid, Korea  

NASA Astrophysics Data System (ADS)

In Korea, two long-term field demonstrations for high temperature superconducting (HTS) cable have been carried out for several years; Korea Electric Power Corporation (KEPCO) and LS Cable Ltd. (LSC) independently. Encouraged at the result of the projects performed in parallel, a new project targeting the real grid operation was launched in the fourth quarter of 2008 with the Korean government’s financial support. KEPCO and LSC are jointly collaborating in the selection of substation, determination of cable specification, design of cryogenic system, and the scheme of protection coordination. A three phase 500 m long HTS cable at a distribution level voltage of 22.9 kV is to be built at 154/22.9 kV Icheon substation located in near Seoul. A hybrid cryogenic system reflecting the contingency plan is being designed including cryocoolers. The HTS cable system will be installed in the second quarter of 2010, being commissioned by the fall of 2010. This paper describes the objectives of the project and design issues of the cable and cryogenic system in detail.

Sohn, S. H.; Lim, J. H.; Yang, B. M.; Lee, S. K.; Jang, H. M.; Kim, Y. H.; Yang, H. S.; Kim, D. L.; Kim, H. R.; Yim, S. W.; Won, Y. J.; Hwang, S. D.

2010-11-01

271

Synthesis of Magnesium Diboride Wires  

Microsoft Academic Search

Magnesium diboride, MgB2, has been of great interest recently due to its high superconducting transition temperature for a material which exhibits properties similar to classical (BCS) superconductors. It has been found that wire segments of MgB2 can be prepared by exposing commercial boron coated filaments to magnesium vapor. This research has shown that the critical current of such wires is

Paul Canfield; Sergei Bud'Ko; Douglas Finnemore Anderson Jr.

2002-01-01

272

Smart Wire Grid: Resisting Expectations  

ScienceCinema

Smart Wire Grid's DSR technology (Discrete Series Reactor) can be quickly deployed on electrical transmission lines to create intelligent mesh networks capable of quickly rerouting electricity to get power where and when it's needed the most. With their recent ARPA-E funding, Smart Wire Grid has been able to move from prototype and field testing to building out a US manufacturing operation in just under a year.

Ramsay, Stewart; Lowe, DeJim

2014-04-09

273

Smart Wire Grid: Resisting Expectations  

SciTech Connect

Smart Wire Grid's DSR technology (Discrete Series Reactor) can be quickly deployed on electrical transmission lines to create intelligent mesh networks capable of quickly rerouting electricity to get power where and when it's needed the most. With their recent ARPA-E funding, Smart Wire Grid has been able to move from prototype and field testing to building out a US manufacturing operation in just under a year.

Ramsay, Stewart; Lowe, DeJim

2014-03-03

274

Silicon Ingot Wire Cutting Animation  

NSDL National Science Digital Library

This Quicktime animation is of a single wire slicing the silicon ingot into thin wafers. By using a thinner wire, and by cutting all wafers at that same time, this minimizes material loss. This animation is the third in a series showing silicon wafer production process after it has been ground to the correct diameter.The previous animation showing silicon ingot rod grinding can be seen here.The next animation in this sequence about silicon wafer lapping can be seen here.

275

Superconducting film on metallic wire  

NASA Technical Reports Server (NTRS)

For technological applications of high T(sub c) superconductors, it will be necessary to overcome the inherent problem of brittleness, to develop materials with high current carrying capacity, and to devise ways of joining superconductors with other materials. These issues will be addressed in the context of superconducting films on metallic wires. These composite systems are expected to produce flexible wires with desirable properties.

Akbar, Sheikh A.

1990-01-01

276

Method of manufacturing superconductor wire  

DOEpatents

A method for forming Nb.sub.3Sn superconducting wire is provided. The method employs a powder-in-tube process using a high-tin intermetallic compound, such as MnSn.sub.2, for producing the Nb.sub.3Sn. The use of a high-tin intermetallic compound enables the process to perform hot extrusion without melting the high-tin intermetallic compound. Alternatively, the method may entail drawing the wire without hot extrusion.

Motowidlo, Leszek

2014-09-16

277

1 mil gold bond wire study.  

SciTech Connect

In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.

Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W.; Rutherford, Brian Milne

2013-05-01

278

Vibrating wires for beam diagnostics  

E-print Network

A new approach to the technique of scanning by wires is developed. Novelty of the method is that the wire heating quantity is used as a source of information about the number of interacting particles. To increase the accuracy and sensitivity of measurements the wire heating measurement is regenerated as a change of wire natural oscillations frequency. By the rigid fixing of the wire ends on the base an unprecedented sensitivity of the frequency to the temperature and to the corresponding flux of colliding particles. The range of used frequencies (tens of kHz) and speed of processes of heat transfer limit the speed characteristics of proposed scanning method, however, the high sensitivity make it a perspective one for investigation of beam halo and weak beam scanning. Traditional beam profile monitors generally focus on the beam core and loose sensitivity in the halo region where a large dynamic range of detection is necessary. The scanning by a vibrating wire can be also successfully used in profiling and det...

Arutunian, S G; Wittenburg, Kay

2015-01-01

279

Mechanisms of plant resistance to 1 g gravity and hypergravity  

NASA Astrophysics Data System (ADS)

Resistance to the gravitational force is one of two major graviresponses in plants, comparable to gravitropism. We have examined mechanisms of gravity resistance using hypergravity conditions produced by centrifugation. Under hypergravity conditions, the expression of the gene encoding 3-hydroxy-3-methylglutaryl-Coenzyme A reductase, which catalyzes a reaction producing mevalonic acid, was up-regulated in Arabidopsis hypocotyls, and the level of membrane sterols was kept higher, without influencing the level or composition of other membrane components. Out of sterols, the levels of steryl glycosides and acyl steryl glycosides were greatly increased, suggesting the stimulation of sterol raft formation under hypergravity conditions. On the other hand, the expression of the majority of alphaand beta-tubulin genes was up-regulated and the percentage of cells with longitudinal cortical microtubules was increased by hypergravity. Hypergravity also increased the expression of genes encoding gamma-tubulin complex and katanin transiently, whereas it decreased that encoding various microtubule-associated proteins such as MAP65. The role of membrane sterols and cortical microtubules in gravity resistance was confirmed using Arabidopsis mutants. The analysis with mutants has also revealed that the signal transduction process via sterol rafts is distinct from that via cortical microtubules. These results indicate that membrane sterol rafts and cortical microtubules are deeply and independently involved in maintenance of normal growth capacity against the gravitational force. To confirm that the hypothesis is applicable to plant resistance to 1 g gravity, we will carry out the space experiment. This experiment, termed Resist Wall, is to be performed on the European Modular Cultivation System onboard the International Space Station (ISS). In the Resist Wall experiment, Arabidopsis mutant strains will be cultivated under microgravity and at 1 g conditions on the ISS up to reproductive stage and phenotypes on growth and development will be compared using video images. Also, we will analyze the levels of gene expression and the cell wall properties of the mutants as well as the wild type, using materials fixed on orbit and collected to earth. The results obtained in this space experiment will also be presented.

Hoson, Takayuki; Matsumoto, Shouhei; Kumasaki, Saori; Higuchi, Sayoko; Soga, Kouichi; Wakabayashi, Kazuyuki; Hashimoto, Takashi; Suzuki, Masashi; Muranaka, Toshiya; Sakaki, Takeshi

280

Plasma arc torch with coaxial wire feed  

DOEpatents

A plasma arc welding apparatus having a coaxial wire feed. The apparatus includes a plasma arc welding torch, a wire guide disposed coaxially inside of the plasma arc welding torch, and a hollow non-consumable electrode. The coaxial wire guide feeds non-electrified filler wire through the tip of the hollow non-consumable electrode during plasma arc welding. Non-electrified filler wires as small as 0.010 inches can be used. This invention allows precision control of the positioning and feeding of the filler wire during plasma arc welding. Since the non-electrified filler wire is fed coaxially through the center of the plasma arc torch's electrode and nozzle, the wire is automatically aimed at the optimum point in the weld zone. Therefore, there is no need for additional equipment to position and feed the filler wire from the side before or during welding.

Hooper, Frederick M (Albuquerque, NM)

2002-01-01

281

Application of genetic algorithm-based fuzzy logic control in wire transport system of wire-EDM machine  

Microsoft Academic Search

Wire tension as well as wire feed should be controlled tightly for the geometry and corner accuracy of wire-EDM. In this paper, a closed-loop wire tension control system for Micro-Wire-EDM is presented to guarantee a smooth wire transport and a constant tension value. In order to keep smooth wire transportation and avoid wire breakage during wire feeding, the reel roller

Mu-Tian Yan; Chi-Cheng Fang

2008-01-01

282

Practical design and operating characteristic analysis of a 10 kW HTS DC induction heating machine  

NASA Astrophysics Data System (ADS)

Conventional induction heaters have been in operation in metal and related industries with poor energy efficiencies of only 50-60%. Also, the efficiency of atmosphere furnace, one of the various heating facilities for metal billets, is about 20%. Hence, a high temperature superconducting (HTS) DC induction heating machine to heat a rotating metal billet under uniform magnetic field generated by the 2G HTS magnet with about 80-90% of the system energy efficiency has been researched in this paper. We presented practical design specification, operational characteristics, and temperature distribution on a 10 kW class HTS DC induction heating machine which had been built and tested. The saturated temperature of an HTS no-insulated(NI) coil in the cryostat fabricated with 100 A of the operating current reached 45.9 K and the magnetic field at the centre point between two iron cores measured 0.2 T. The rotating machine for 4.1 kg of the aluminum billet was tested on 1760 rpm of the rated rotating speed. The final temperature of the aluminum billet has risen up to 500 °C for 480 s. The research outcomes are expected to be useful for the design of a large scale HTS DC induction heating machine in industries.

Choi, Jongho; Kim, Kwangmin; Park, Minwon; Yu, In-Keun; Kim, Seokho; Sim, Kideok; Kim, Hae-jong

2014-09-01

283

Wires for Shape Memory Actuators  

NASA Astrophysics Data System (ADS)

The effect of non-conventional electrical pulse treatment on microstructure and shape memory response of Ni49Ti51 wires was studied. High-power rapid current square pulses were applied to cold-drawn wires of 25 µm diameter. The TEM microstructures showed equiaxial recrystallization, with average grain size in the 100 nm range, after a double current pulse lasting 10 ms. Rapid current pulse treatment in Ti-rich NiTi induces shape memory effect with reduced thermal hysteresis and high recovery strain values. This novel treatment might replace conventional pre-device shape setting/training of the wire with a post-device shape setting with promising industrial advantages.

Casati, R.; Vedani, M.; Gialanella, S.; Tuissi, A.

2014-07-01

284

Wire Detection Algorithms for Navigation  

NASA Technical Reports Server (NTRS)

In this research we addressed the problem of obstacle detection for low altitude rotorcraft flight. In particular, the problem of detecting thin wires in the presence of image clutter and noise was studied. Wires present a serious hazard to rotorcrafts. Since they are very thin, their detection early enough so that the pilot has enough time to take evasive action is difficult, as their images can be less than one or two pixels wide. Two approaches were explored for this purpose. The first approach involved a technique for sub-pixel edge detection and subsequent post processing, in order to reduce the false alarms. After reviewing the line detection literature, an algorithm for sub-pixel edge detection proposed by Steger was identified as having good potential to solve the considered task. The algorithm was tested using a set of images synthetically generated by combining real outdoor images with computer generated wire images. The performance of the algorithm was evaluated both, at the pixel and the wire levels. It was observed that the algorithm performs well, provided that the wires are not too thin (or distant) and that some post processing is performed to remove false alarms due to clutter. The second approach involved the use of an example-based learning scheme namely, Support Vector Machines. The purpose of this approach was to explore the feasibility of an example-based learning based approach for the task of detecting wires from their images. Support Vector Machines (SVMs) have emerged as a promising pattern classification tool and have been used in various applications. It was found that this approach is not suitable for very thin wires and of course, not suitable at all for sub-pixel thick wires. High dimensionality of the data as such does not present a major problem for SVMs. However it is desirable to have a large number of training examples especially for high dimensional data. The main difficulty in using SVMs (or any other example-based learning method) is the need for a very good set of positive and negative examples since the performance depends on the quality of the training set.

Kasturi, Rangachar; Camps, Octavia I.

2002-01-01

285

Designing potentials by sculpturing wires  

SciTech Connect

Magnetic trapping potentials for atoms on atom chips are determined by the current flow in the chip wires. By modifying the shape of the conductor we can realize specialized current flow patterns and therefore microdesign the trapping potentials. We have demonstrated this by nano-machining an atom chip using the focused ion beam technique. We built a trap, a barrier, and using a Bose-Einstein Condensate as a probe we showed that by polishing the conductor edge the potential roughness on the selected wire can be reduced. Furthermore, we give different other designs and discuss the creation of a one-dimensional magnetic lattice on an atom chip.

Della Pietra, Leonardo; Aigner, Simon; Groth, Soenke [Physikalisches Institut, Universitaet Heidelberg, 69120 Heidelberg (Germany); Hagen, Christoph von; Schmiedmayer, Joerg [Physikalisches Institut, Universitaet Heidelberg, 69120 Heidelberg (Germany); Atominstitut der Oesterreichischen Universitaeten, TU-Wien, A-1020 Vienna (Austria); Bar-Joseph, Israel [Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 7600 (Israel); Lezec, Henri J. [ISIS, Universite Louis Pasteur, 8 Allee Gaspard Monge, 67083 Strasbourg (France)

2007-06-15

286

Quantitative assessment of tension in wires of fine-wire external fixators.  

PubMed

Fine-wire fixators are widely used in fracture management. Stable fixation requires the wires maintaining tension throughout the treatment. Clinical experience indicates that wire site complications relate to wire tension. However, there lacks a method to assess wire tension quantitatively in the clinic. The objective of this study was to develop a quantitative assessment method for in situ wire tension and to investigate the factors that influence the assessment. An apparatus was developed based on a linear variable differential transformer (LVDT) displacement transducer that measured the deflection of the testing wire with respect to a parallel reference wire when a constant transverse force of 30N was applied to the testing wire. The wire deflection measured was correlated with the wire tension measured by the force transducer. The experiment was performed under different conditions to assess the effect of bone-clamp distance, reference wire tension, number of wires, and fracture stiffness. The results showed that there was a significant and negative correlation between wire tension and deflection and the bone-clamp distance was the most important factor that affected the wire tension-deflection relationship. The assessment method makes it possible to investigate the relationship between wire tension and wire site complications in the clinic. PMID:15604006

Dong, Yin; Saleh, Micheal; Yang, Lang

2005-01-01

287

Conventional Hot-Wire Anemometer Micro Hot Wire  

E-print Network

;- Heat is introduced into the sensing element by Joule heating and is lost by convection, conduction of sensor Tf: temperature of fluid environment The radiation loss is much less than the convection losses wire anemometry use the convective heat transfer from from heated sensor to the surrounding fluid

Leu, Tzong-Shyng "Jeremy"

288

Effect of Wire Purity on Copper Wire Bonding  

Microsoft Academic Search

Cu bonding has been making a wave in the IC packaging industry due to the combined efforts of wire, capillary and wirebonder manufacturers. The present challenge in copper bonding resides in minimizing the aluminium squeeze of the aluminium metallization of bond pads. This demands the copper ball to possess a lower yield stress for reduced energy to deform. In this

Narasimalu Srikanth; J. Premkumar; M. Sivakumar; Y. M. Wong; C. J. Vath

2007-01-01

289

RIGBY SPECIALITY WIRES LIMITED NEW WIRE PRODUCT IS ALL  

E-print Network

resistant properties for the installed cable, yet make it less prone to abrasion, thereby www resistant and insulated electrical wiring products are used in a wide range of applications, from public industries, but traditional insulation materials can prove susceptible to abrasion when installed

Berzins, M.

290

Cryogenic experiences during W7-X HTS-current lead tests  

SciTech Connect

The Karlsruhe Institute of Technology (KIT) was responsible for design, production and test of the High Temperature Superconductor (HTS) current leads (CL) for the stellerator Wendelstein 7-X (W7-X). 16 current leads were delivered. Detailed prototype tests as well as the final acceptance tests were performed at KIT, using a dedicated test cryostat assembled beside and connected to the main vacuum vessel of the TOSKA facility. A unique feature is the upside down orientation of the current leads due to the location of the power supplies in the basement of the experimental area of W7-X. The HTS-CL consists of three main parts: the cold end for the connection to the bus bar at 4.5 K, the HTS part operating in the temperature range from 4.5 K to 65 K and a copper heat exchanger (HEX) in the temperature range from 65 K to room temperature, which is cooled with 50 K helium. Therefore in TOSKA it is possible to cool test specimens simultaneously with helium at two different temperature levels. The current lead tests included different scenarios with currents up to 18.2 kA. In total, 10 cryogenic test campaigns with a total time of about 24 weeks were performed till beginning of 2013. The test facility as well as the 2 kW cryogenic plant of ITEP showed a very good reliability. However, during such a long and complex experimental campaign, one has to deal with failures, technical difficulties and incidents. The paper gives a summary of the test performance comprising the test preparation and operation. This includes the performance and reliability of the refrigerator and the test facility with reference to the process measuring and control system, the data acquisition system, as well as the building infrastructure.

Richter, Thomas; Lietzow, Ralph [Karlsruhe Institute of Technology, Institute for Technical Physics (ITEP), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2014-01-29

291

3D modeling and simulation of 2G HTS stacks and coils  

NASA Astrophysics Data System (ADS)

Use of 2G HTS coated conductors in several power applications has become popular in recent years. Their large current density under high magnetic fields makes them suitable candidates for high power capacity applications such as stacks of tapes, coils, magnets, cables and current leads. For this reason, modeling and simulation of their electromagnetic properties is very desirable in the design and optimization processes. For many applications, when symmetries allow it, simple models consisting of 1D or 2D representations are well suited for providing a satisfying description of the problem at hand. However, certain designs such as racetrack coils and finite-length or non-straight stacks, do pose a 3D problem that cannot be easily reduced to a 2D configuration. Full 3D models have been developed, but their use for simulating superconducting devices is a very challenging task involving a large-scale computational problem. In this work, we present a new method to simulate the electromagnetic transient behavior of 2G HTS stacks and coils. The method, originally used to model stacks of straight superconducting tapes or circular coils in 2D, is now extended to 3D. The main idea is to construct an anisotropic bulk-like equivalent for the stack or coil, such that the geometrical layout of the internal alternating structures of insulating, metallic, superconducting and substrate layers is reduced while keeping the overall electromagnetic behavior of the original device. Besides the aforementioned interest in modeling and simulating 2G HTS coated conductors, this work provides a further step towards efficient 3D modeling and simulation of superconducting devices for large-scale applications.

Zermeño, Víctor M. R.; Grilli, Francesco

2014-04-01

292

Modeling of a 22.9 kV 50 MVA superconducting power cable based on PSCAD/EMTDC for application to the Icheon substation in Korea  

NASA Astrophysics Data System (ADS)

Two projects for high temperature superconducting (HTS) power cable have been carried out in Korea since 2001. One of them is a HTS cable project in DAPAS (Development of Advanced Power system by Applied Superconductivity technologies) program funded by the Ministry of Education, Science and Technology. In this project, LS Cable Ltd. (LSC) and Korea Electrotechnology Research Institute (KERI) jointly developed a 22.9 kV, 50 MVA, 3 phase, 100 m HTS cable using first generation (1G) HTS wire in 2006. The HTS cable system has been tested in a power test center of Korea Electric Power Corporation (KEPCO). LSC and KEPCO have been developing a 22.9 kV, 50 MVA, 3 phase, 500 m HTS cable system using second generation (2G) HTS wire since 2008, based on the technology of the DAPAS project. This project is called as GENI (Green Superconducting Electric Power Network at the Icheon Substation) project. The target of GENI project is to install and operate the HTS cable system in the Icheon substation located in near Seoul. In order to analyze the Icheon substation power system employing the HTS cable, an analysis model of the HTS cable is necessary. This paper describes the development of an analysis model for the 22.9 kV, 50 MVA HTS cable that will be applied to the Icheon substation in Korea.

Lee, S.; Yoon, J.; Lee, B.; Yang, B.

2011-11-01

293

Characterization of Hybrid Ferroelectric/HTS Thin Films for Tunable Microwave Components  

NASA Technical Reports Server (NTRS)

Since the discovery of High-Temperature-Superconductors (HTS) in 1986, a diversity of HTS-based microwave components has been demonstrated. Because of their low conductor losses, HTS-based components are very attractive for integration into microwave circuits for space communication systems. Recent advancements have made deposition of ferroelectric thin films onto HTS thin films possible. Due to the sensitivity of the ferroelectric's dielectric constant (epsilon(sub r)) to an externally applied electric field (E), ferroelectric/superconducting structures could be used in the fabrication of low loss, tunable microwave components. In this paper, we report on our study of Ba(0.5)Sr(0.5)TiO3/YBa2Cu3O(7-delta) and Ba(0.08)Sr(0.92)TiO3/YBa2Cu3O(7-delta) ferroelectric/superconducting thin films on lanthanum aluminate (LaAlO3) substrates. For the (Ba:Sr, 0.50:0.50) epitaxial sample, a epsilon(sub r) of 425 and a loss tangent (tan delta) of 0.040 were measured at 298 K, 1.0 MHz, and zero applied E. For the same sample, a epsilon(sub r) of 360 and tan delta of 0.036 were obtained at 77 K, 1.0 MHz, and zero applied E. Variations in epsilon(sub r) from 180 to 360 were observed over an applied E range of 0V/cm less than or equal to E less than or equal to 5.62 x 10(exp 4) V/cm with little change in tan delta. However, the range of epsilon(sub r) variation for the polycrystalline (Ba:Sr, 0.08:0.92) sample over 0V/cm less than or equal to E less than or equal to 4.00 x 10(exp 4) V/cm was only 3.6 percent while tan delta increased markedly. These results indicate that a lack of epitaxy between the ferroelectric and superconducting layers decreases tuning and increases microwave losses.

Winters, M. D.; Mueller, C. H.; Bhasin, K. B.; Miranda, F. A.

1996-01-01

294

Ion-size effects in HTS cuprates -- dielectric versus magnetic pairing  

NASA Astrophysics Data System (ADS)

We have been exploring the systematic effects of changing ion size on superconducting and normal-state properties of the HTS cuprates. In the model system RA2Cu3Oy (where R = La,, Lu and A=Ba2-xSrx) the maximum Tc in the dome-shaped phase curve can be shifted from 70 to 110 K in the model system. Surprisingly Tc correlates with the dielectric properties and not the magnetic properties. This highlights the fundamental importance of charge fluctuation and dielectric screening in the cuprates and may signal a novel pairing mechanism having its origin with quantized waves of electronic polarization.

Tallon, Jeffery; Mallett, Ben; Ashcroft, Neil

2013-03-01

295

A Study on Deterioration of HTS Trapped Flux Under Thermal Cycle Operation  

NASA Astrophysics Data System (ADS)

This paper presents a change of magnetic flux trapped in the YBa2Cu3Ox (YBCO) disk under thermal excursions. We have supposed a new cryocooler system for the high temperature superconducting (HTS) magnet in which the thermal cycles are generated. As a result, it can be found that the trapped flux deteriorated at the first temperature-rise stage, but it kept constant after the first temperature-fall stage. The deterioration at the first temperature-rise stage can be explained by the Bean's model, but the result of the following stages can't be explained by it.

Kinoshita, K.; Sawa, K.; Iwasa, Y.

2004-06-01

296

47 CFR 32.2431 - Aerial wire.  

Code of Federal Regulations, 2014 CFR

...CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2431 Aerial wire. (a) This account shall include the original cost of bare line wire and other...

2014-10-01

297

30 CFR 56.12047 - Guy wires.  

Code of Federal Regulations, 2013 CFR

...Guy wires. Guy wires of poles supporting high-voltage transmission lines shall meet the requirements for grounding or insulator protection of the National Electrical Safety Code, part 2, entitled “Safety Rules for the Installation and...

2013-07-01

298

New insulation constructions for aerospace wiring applications  

NASA Technical Reports Server (NTRS)

Outlined in this presentation is the background to insulation constructions for aerospace wiring applications, the Air Force wiring policy, the purpose and contract requirements of new insulation constructions, the test plan, and the test results.

Slenski, George

1994-01-01

299

Electrical wire insulation and electromagnetic coil  

DOEpatents

An electromagnetic coil for high temperature and high radiation application in which glass is used to insulate the electrical wire. A process for applying the insulation to the wire is disclosed which results in improved insulation properties.

Bich, George J. (Penn Hills, PA); Gupta, Tapan K. (Monroeville, PA)

1984-01-01

300

30 CFR 57.12047 - Guy wires.  

Code of Federal Regulations, 2011 CFR

...Guy wires. Guy wires of poles supporting high-voltage transmission lines shall meet the requirements for grounding or insulator protection of the National Electrical Safety Code, part 2, entitled “Safety Rules for the Installation and...

2011-07-01

301

30 CFR 56.12047 - Guy wires.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12047 Guy wires. Guy wires of poles supporting high-voltage transmission lines shall meet the...

2010-07-01

302

30 CFR 57.12047 - Guy wires.  

Code of Federal Regulations, 2013 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12047 Guy wires. Guy wires of poles supporting high-voltage...

2013-07-01

303

30 CFR 56.12047 - Guy wires.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12047 Guy wires. Guy wires of poles supporting high-voltage transmission lines shall meet the...

2011-07-01

304

30 CFR 57.12047 - Guy wires.  

Code of Federal Regulations, 2012 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12047 Guy wires. Guy wires of poles supporting high-voltage...

2012-07-01

305

30 CFR 56.12047 - Guy wires.  

Code of Federal Regulations, 2014 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12047 Guy wires. Guy wires of poles supporting high-voltage transmission lines shall meet the...

2014-07-01

306

30 CFR 56.12047 - Guy wires.  

Code of Federal Regulations, 2012 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12047 Guy wires. Guy wires of poles supporting high-voltage transmission lines shall meet the...

2012-07-01

307

30 CFR 57.12047 - Guy wires.  

Code of Federal Regulations, 2014 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12047 Guy wires. Guy wires of poles supporting high-voltage...

2014-07-01

308

30 CFR 57.12047 - Guy wires.  

Code of Federal Regulations, 2010 CFR

...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Electricity Surface and Underground § 57.12047 Guy wires. Guy wires of poles supporting high-voltage...

2010-07-01

309

Identification of a positively charged platform in Staphylococcus aureus HtsA that is essential for ferric staphyloferrin A transport.  

PubMed

In response to iron starvation, Staphylococcus aureus secretes both staphyloferrin A and staphyloferrin B, which are high-affinity iron-chelating molecules. The structures of both HtsA and SirA, the ferric-staphyloferrin A [Fe(III)-SA] and ferric-staphyloferrin B [Fe(III)-SB] receptors, respectively, have recently been determined. The structure of HtsA identifies a novel form of ligand entrapment composed of many positively charged residues. Through ionic interactions, the binding pocket appears highly adapted for the binding of the highly anionic siderophore SA. However, biological validation of the importance of the nine SA-interacting residues (six arginines, one tyrosine, one histidine, and one lysine) has not been previously performed. Here, we mutated each of the Fe(III)-SA-interacting residues in HtsA and found that substitutions R104A, R126A, H209A, R306A, and R306K resulted in a reduction of binding affinity of HtsA for Fe(III)-SA. While mutation of almost all proposed ligand-interacting residues decreased the ability of S. aureus cells to transport (55)Fe(III)-SA, S. aureus expressing HtsA R104A, R126A, R306A, and R306K showed the greatest transport defects and were incapable of growth in iron-restricted growth media in a SA-dependent manner. These three residues cluster together and, relative to other residues in the binding pocket, move very little between the apo and closed holo structures. Their essentiality for receptor function, together with structural information, suggests that they form a positively charged platform that is required for initial contact with the terminal carboxyl groups of the two citrates in the Fe(III)-SA complex. This is a likely mechanism by which HtsA discerns iron-bound SA from iron-free SA. PMID:25050909

Cooper, John D; Hannauer, Mélissa; Marolda, Cristina L; Briere, Lee-Ann K; Heinrichs, David E

2014-08-12

310

The decay properties of the trapped magnetic field in HTS bulk superconducting actuator by AC controlled magnetic field  

NASA Astrophysics Data System (ADS)

The electric device applications of a high temperature superconducting (HTS) bulk magnet, having stable levitation and suspension properties according to their strong flux pinning force, have been proposed and developed. We have been investigating a three-dimensional (3-D) superconducting actuator using HTS bulks to develop a non-contract transportation device which moves freely in space. It is certain for our proposed 3-D superconducting actuator to be useful as a transporter used in a clean room where silicon wafers, which do not like mechanical contact and dust, are manufactured. The proposed actuator consists of the trapped HTS bulk as a mover and two-dimensionally arranged electromagnets as a stator. Up to now, the electromagnets consisted with iron core and copper coil were used as a stator, and each electromagnet was individually controlled using DC power supplies. In our previous work, the unstable movement characteristics of HTS bulk were observed under the DC operation, and the AC electromagnets driven with AC controlled current was proposed to solve these problems. In general, the trapped magnetic field in HTS bulk was decayed by a time-varying external magnetic field. Thus, it needs to optimize the shapes of AC electromagnets and operating patterns, the decay properties of the trapped magnetic field in the HTS bulk mover by the AC magnetic field should be cleared. In this paper, the influences of the frequency, the overall operating time, the strength of magnetization field and drive current against the decay of trapped magnetic field were experimentally studied using the fabricated AC electromagnets.

Kim, S. B.; Uwani, Y.; Joo, J. H.; Kawamoto, R.; Jo, Y. S.

2011-11-01

311

NEMA wire and cable standards development programs  

NASA Technical Reports Server (NTRS)

The National Electrical Manufacturers Association (NEMA) is the nation's largest trade association for manufacturers of electrical equipment. Its member companies produce components, end-use equipment and systems for the generation, transmission, distribution, control and use of electricity. The wire and cable division is presented in 6 sections: building wire and cable, fabricated conductors, flexible cords, high performance wire and cable, magnet wire, and power and control cable. Participating companies are listed.

Baird, Robert W.

1994-01-01

312

Novel Wiring Technologies for Aerospace Applications  

NASA Technical Reports Server (NTRS)

Because wire failure in aerospace vehicles could be catastrophic, smart wiring capabilities have been critical for NASA. Through the years, researchers at Kennedy Space Center (KSC) have developed technologies, expertise, and research facilities to meet this need. In addition to aerospace applications, NASA has applied its knowledge of smart wiring, including self-healing materials, to serve the aviation industry. This webinar will discuss the development efforts of several wiring technologies at KSC and provide insight into both current and future research objectives.

Gibson, Tracy L.; Parrish, Lewis M.

2014-01-01

313

Shape-Memory Wires Switch Rotary Actuator  

NASA Technical Reports Server (NTRS)

Thermomechanical rotary actuator based on shape-memory property of alloy composed of equal parts of titanium and nickel. If alloy stretched while below transition temperature, it reverts to original length when heated above transition temperature. Two capstans on same shaft wrapped with shape-memory wires. As one wire heated, it contracts and stretches opposite wire. Wires heated in alternation so they switch shaft between two extreme angular positions; "on" and "off" positions of rotary valve.

Brudnicki, Myron J.

1992-01-01

314

Force on a Current Carrying Wire  

NSDL National Science Digital Library

Students use a simple set up consisting of a current carrying wire and a magnet to explore the forces which enable biomedical imaging. In doing so, students run a current through a wire and then hold magnets in various positions to establish and explore the magnetic force acting on the wire. They move the magnets and change the current in the wire to explore how the force changes.

VU Bioengineering RET Program, School of Engineering,

315

Fabrication of tungsten wire needles  

SciTech Connect

Fine point needles for field emissoin are conventionally produced by electrolytically or chemically etching tungsten wire. Points formed in this manner have a typical tip radius of about 0.5 microns and a cone angle of some 30 degrees. The construction of needle matrix detector chambers has created a need for tungsten needles whose specifications are: 20 mil tungsten wire, 1.5 inch total length, 3 mm-long taper (resulting in a cone angle of about 5 degrees), and 25 micron-radius point (similar to that found on sewing needles). In the process described here for producing such needles, tungsten wire, immersed in a NaOH solution and in the presence of an electrode, is connected first to an ac voltage and then to a dc supply, to form a taper and a point on the end of the wire immersed in the solution. The process parameters described here are for needles that will meet the above specifications. Possible variations will be discussed under each approprite heading.

Roder, A.

1983-02-01

316

Wire Scanner Motion Control Card  

Microsoft Academic Search

Scientists require a certain beam quality produced by the accelerator rings at CERN. The discovery potential of LHC is given by the reachable luminosity at its interaction points. The luminosity is maximized by minimizing the beam size. Therefore an accurate beam size measurement is required for optimizing the luminosity. The wire scanner performs very accurate profile measurements, but as it

S E Forde; B Dehning

2006-01-01

317

Telesynergy V3 Wiring Diagram  

Cancer.gov

Extron 8 port Video/Audio Switch WAVE Camera Telesynergy v3 Wiring Diagram ISDN T1/PRI Module CTRLR 0 Legend: S-Video Audio VGA DVI USB RS-232 Serial Microphone Ethernet Planar C5i AMD Exam Cam Canon Document Camera Olympus BX51 Sony DVD Recorder JVC

318

Plated wire random access memories  

NASA Technical Reports Server (NTRS)

A program was conducted to construct 4096-work by 18-bit random access, NDRO-plated wire memory units. The memory units were subjected to comprehensive functional and environmental tests at the end-item level to verify comformance with the specified requirements. A technical description of the unit is given, along with acceptance test data sheets.

Gouldin, L. D.

1975-01-01

319

Rupture failure and mechanical strength of the electrode wire used in wire EDM  

Microsoft Academic Search

In the application of wire EDM, wire rupture is very troublesome and impedes further increase of cutting speed. Instead of the spark characteristics or the temperature distribution, the rupture mechanism and the mechanical strength of the wire are the focus of this investigation. Wire rupture is a mechanical failure in essence, although the process heat has significant influence on the

Y. F. Luo

1999-01-01

320

75 FR 4584 - Wire Decking From China  

Federal Register 2010, 2011, 2012, 2013, 2014

...from carbon or alloy steel wire that has been welded into a mesh pattern. The wire may be galvanized or plated (e.g., chrome, zinc or nickel coated), coated (e.g., with paint, epoxy, or plastic), or uncoated (``raw''). The wire...

2010-01-28

321

Home and School Technology: Wired versus Wireless.  

ERIC Educational Resources Information Center

Presents results of informal research on smart homes and appliances, structured home wiring, whole-house audio/video distribution, hybrid cable, and wireless networks. Computer network wiring is tricky to install unless all-in-one jacketed cable is used. Wireless phones help installers avoid pre-wiring problems in homes and schools. (MLH)

Van Horn, Royal

2001-01-01

322

Industrial electromagnetic checkout of armored wiring  

NASA Astrophysics Data System (ADS)

A method for testing whether armored wiring can withstand EMP's caused by nuclear explosions is described. The wires are checked in their production cases, using a strip line antenna as pulse source. Only one measurement per connector is made, with the connector conductors in parallel. The method is quick, repeatable, and does not damage the wiring.

Ferre, J.

1983-03-01

323

A Novel Electrical Insulating Material for 275 kV High-Voltage HTS Cable with Low Dielectric Loss  

NASA Astrophysics Data System (ADS)

In the case of high temperature superconducting (HTS) power transmission cables at high voltage operation, the electrical insulation technique in consideration of the dielectric loss reduction becomes crucial. In this paper, we focused on a Tyvek/polyethylene (PE) sheet, instead of the conventional polypropylene laminated paper (PPLP). We obtained the dielectric characteristics (epsilonr, tan?) and partial discharge inception strength (PDIE) of PPLP, Tyvek and Tyvek/PE. We pointed out that the dielectric loss of 275 kV HTS cable with Tyvek/PE insulation will be reduced to 21 % of that with PPLP, and the total electrical loss including the AC loss will be reduced to 41 %.

Hayakawa, N.; Nishimachi, S.; Maruyama, O.; Ohkuma, T.; Liu, J.; Yagi, M.

2014-05-01

324

Protective relay system for the first demonstration of the HTS cable and the SFCL in live grid in Korea  

NASA Astrophysics Data System (ADS)

This study proposed a novel power protection system for the application of 22.9 kV HTS cable and SFCL systems to the Icheon substation in South Korea, and studied the protective coordination of the proposed system using a transient simulation program, PSCAD/EMTDC. Korea Electric Power Cooperation (KEPCO) designed and reconstructed the protection system of the Icheon substation based on the results of this study. The 22.9 kV, 50 MVA HTS cable and 22.9 kV, 630 A hybrid SFCL systems have been successfully operated in the live power grid of the Icheon substation since August, 2011.

Lee, Seung Ryul; Yoon, Jaeyoung; Yang, Byeong-mo; Lee, Byongjun

2013-11-01

325

Arc tracking properties of the aging wires in aircraft  

Microsoft Academic Search

A modern commercial aircraft contains hundreds of miles of wiring. This vastly increased use of wiring, in conjunction with decreased insulation thickness, has increased the incidence of wire-related aircraft safety problems. Due to thermal, electrical, mechanical and chemical overstress, the aircraft wiring will be aged and the wire insulation will be decreased. Microscopic cracking occurs in wire insulation as the

Wang Yongxing; Dong Enyuan; Cong Jiyuan; Zou Jiyan; Dieter Koenig

2008-01-01

326

Accuracy improvement of wire-EDM by real-time wire tension control  

Microsoft Academic Search

In this paper, a closed-loop wire tension control system for a wire-EDM machine is presented to improve the machining accuracy. Dynamic models of the wire feed control apparatus and wire tension control apparatus are derived to analyze and design the control system. PI controller and one-step-ahead adaptive controller are employed to investigate the dynamic performance of the closed-loop wire tension

Mu-Tian Yan; Pin-Hsum Huang

2004-01-01

327

Frequency response in short thermocouple wires  

NASA Technical Reports Server (NTRS)

Theoretical expressions are derived for the steady state frequency response of a thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for a nonuniform wire with unequal material properties and wire diameters across the junction. The amplitude ratio at low frequency omega approaches 0 agrees with the results of Scadron and Warshawsky (1952) for a steady state temperature distribution. Moreover, the frequency response for a nonuniform wire in the limit of infinite length l approaches infinity is shown to reduce to a simple expression that is analogous to the classic first order solution for a thermocouple wire with uniform properties. Theoretical expressions are also derived for the steady state frequency response of a supported thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a supported one material wire and a two material wire with unequal material properties across the junction. For the case of a one material supported wire, an exact solution is derived which compares favorably with an approximate expression that only matches temperatures at the support junction. Moreover, for the case of a two material supported wire, an analytical expression is derived that closely correlates numerical results. Experimental measurements are made for the steady state frequency response of a supported thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a supported one material wire (type K) and a two material wire (type T) with unequal material properties across the junction. The data for the amplitude ratio and phase angle are correlated to within 10 pct. with the theoretical predictions of Forney and Fralick (1991). This is accomplished by choosing a natural frequency omega sub n for the wire data to correlate the first order response at large gas temperature frequencies. It is found that a large bead size, however, will increase the amplitude ratio at low frequencies but decrease the natural frequency of the wire. The phase angle data are also distorted for imperfect junctions.

Forney, L. J.; Meeks, E. L.; Ma, J.; Fralick, G. C.

1992-01-01

328

Development of 1 MW-class HTS motor for podded ship propulsion system  

NASA Astrophysics Data System (ADS)

To reduce fuel consumption and lead to a major reduction of pollution from NOx, SOx and CO2, the electric ship propulsion system is one of the most prospective substitutes for conventional ship propulsion systems. In order to spread it, innovative technologies for the improvement of the power transmission are required. The high temperature superconducting technology has the possibility for a drastic reduction of power transmission loss. Recently, electric podded propulsions have become popular for large cruise vessels, icebreakers and chemical tankers because of the flexibility of the equipment arrangement and the stern hull design, and better maneuverability in harbour, etc. In this paper, a 1 MW-class High temperature superconducting (HTS) motor with high efficiency, smaller size and simple structure, which is designed and manufactured for podded propulsion, is reported. For the case of a coastal ship driven by the optimized podded propulsion in which the 1MW HTS motor is equipped, the reductions of fluid dynamic resistance and power transmission losses are demonstrated. The present research & development has been supported by the New Energy and Industrial Technology Development Organization (NEDO).

Umemoto, K.; Aizawa, K.; Yokoyama, M.; Yoshikawa, K.; Kimura, Y.; Izumi, M.; Ohashi, K.; Numano, M.; Okumura, K.; Yamaguchi, M.; Gocho, Y.; Kosuge, E.

2010-06-01

329

Design and fabrication of 5 GHz band pass filter using circle-type HTS bulk resonator  

NASA Astrophysics Data System (ADS)

We designed and fabricated a transmit band pass filter (BPF) using circle-type high temperature superconductor (HTS) bulk resonators. A Dy-Ba-Cu-O bulk was fabricated using a modified quench and melt growth (QMG) process and cut into specimens of 8.40 and 8.44 mm in diameter and 0.5 mm thick for use as the HTS bulk resonators. A three-pole stripline (SL) BPF was designed based on a Chebyshev function and the frequency response and electromagnetic field of the filter were simulated using a three-dimensional electromagnetic field simulator. From the results of the simulation, the center frequency, bandwidth, insertion loss, and ripple of the designed filter were 4.97 GHz, 100 MHz, 0.03 dB, and 0.048 dB, respectively. In the experimental results on the actual fabricated filter, the filtering response was clearly observed; however, the center frequency of 5.46 GHz was higher than that of the simulation. The simulated maximum surface current in the resonators of the SL filter was approximately 86% smaller than that of a conventional hairpin filter. Furthermore, the measured response of the Dy-Ba-Cu-O bulk filter at an input power of 20 dBm was almost the same as that at 0 dBm. These results mean that an SL filter using a Dy-Ba-Cu-O bulk resonator may be practicable as a high-power transmit BPF.

Saito, A.; Teshima, H.; Ono, S.; Hirano, H.; Hirano, S.; Ohshima, S.

2007-10-01

330

Testing of machine wound second generation HTS tape Vacuum Pressure Impregnated coils  

NASA Astrophysics Data System (ADS)

Delamination of second generation (2G) High Temperature Superconducting (HTS) tapes has previously been reported when using resin based insulation systems for wound coils. One proposed root cause is the differential thermal contraction between the coil former and the resin encapsulated coil turns resulting in the tape c-axis tensile stress being exceeded. Importantly, delamination results in unacceptable degradation of the superconductor critical current level. To mitigate the delamination risk and prove winding, jointing and Vacuum Pressure Impregnation (VPI) processes in the production of coils for superconducting rotating machines at GE Power Conversion two scaled trial coils have been wound and extensively tested. The coils are wound from 12mm wide 2G HTS tape supplied by AMSC onto stainless steel 'racetrack' coil formers. The coils are wound in two layers which include both in-line and layer-layer joints subject to in-process test. The resin insulation system chosen is VPI and oven cured. Tests included; insulation resistance, repeat quench and recovery of the superconductor, heat runs and measurement of n-value, before and after multiple thermal cycling between ambient and 35 Kelvin. No degradation of coil performance is evidenced.

Swaffield, D.; Lewis, C.; Eugene, J.; Ingles, M.; Peach, D.

2014-05-01

331

Dynamic Characteristics of Pressure Build Up Tank for HTS Power Cable Refrigeration System  

NASA Astrophysics Data System (ADS)

HTS power cables are cooled by the forced circulation of sub-cooled liquid nitrogen to remove heat loss and maintain a cryogenic temperature. The refrigeration systems used consist of cryocoolers, a pressure build-up tank, heat exchangers, and circulation pumps. Liquid nitrogen expands or shrinks according to the temperature variation inside the fixed volume of the refrigeration system and the cable cryostat. The system pressure also changes depending on the volume change of the liquid nitrogen. The pressure of the liquid nitrogen should be kept above a certain level to ensure its dielectric strength. In addition, the pressure should be kept below the allowable pressure level considering the mechanical strength of the refrigeration system. To enhance the pressure controllability, external heating and cooling should be possible in the pressure build-up tank. For the precise modeling of the pressure build-up tank, thermal stratification and axial thermal conduction are considered. An analysis of such a refrigeration system is performed using the commercial code 'Sinda/fluint', a comprehensive finite-difference, one-dimensional, lumped parameter tool. This paper presents the transient thermo-hydraulic characteristics and the design directions of an HTS cable refrigeration system according to a variable heat load including pressure build-up tank.

Kim, Dongmin; Park, Heecheol; Kim, Seokho; Jang, Hyunman; Kim, Yanghun

332

Qualification High Voltage Testing of Short Triax HTS Cables in the Laboratory  

SciTech Connect

In order to qualify the electrical insulation design of future HTS cables installed in the electric grid, a number of high voltage qualification tests are generally performed in the laboratory on either single-phase model cables and/or actual three-phase cable samples. Prior to installation of the 200-m Triax HTS cable at the American Electric Power Bixby substation near Columbus, Ohio, in September, 2006, such tests were conducted on both single-phase model cables made at ORNL and tri-axial cable sections cut off from cable made on a production run. The three-phase tri-axial design provides some specific testing challenges since the ground shield and three phases are concentric about a central former with each phase separated by dielectric tape insulation immersed in liquid nitrogen. The samples were successfully tested and qualified for partial discharge inception, AC withstand, and lightning impulse where voltage is applied to one phase with the other phases grounded. In addition one of the phase pairs was tested for dc withstand as a ldquoworst caserdquo scenario to simulate the effect of VLF (Very Low Frequency) tests on the actual cable installed at the Bixby site. The model and prototype cables will be described and the high voltage test results summarized.

James, David Randy [ORNL; Sauers, Isidor [ORNL; Ellis, Alvin R [ORNL; Tuncer, Enis [ORNL; Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Duckworth, Robert C [ORNL; Rey, Christopher M [ORNL

2009-01-01

333

Consideration of sub-cooled LN2 circulation system for HTS power machines  

NASA Astrophysics Data System (ADS)

We consider a sub-cooled liquid nitrogen (LN) circulation system for HTS power equipment. The planned circulation system consists of a sub-cool heat exchanger (subcooler) and a circulation pump. The sub-cooler will be connected to a neon turbo- Brayton cycle refrigerator with a cooling power of 2 kW at 65 K. Sub-cooled LN will be delivered into the sub-cooler by the pump and cooled within it. Sub-cooled LN is adequate fluid for cooling HTS power equipment, because its dielectric strength is high and it supports a large critical current. However, a possibility of LN solidification in the sub-cooler is a considerable issue. The refrigerator will produce cold neon gas of about 60 K, which is lower than the nitrogen freezing temperature of 63 K. Therefore, we designed two-stage heat exchangers which are based on a plate-fin type and a tube-intube type. Process simulations of those heat exchangers indicate that sub-cooled LN is not frozen in either sub-cooler. The plate-fin type sub-cooler is consequently adopted for its reliability and compactness. Furthermore, we found that a cooling system with a Brayton refrigerator has the same total cooling efficiency as a cooling system with a Stirling refrigerator.

Yoshida, Shigeru; Hirai, Hirokazu; Nara, N.; Nagasaka, T.; Hirokawa, M.; Okamoto, H.; Hayashi, H.; Shiohara, Y.

2012-06-01

334

A 100-W grade closed-cycle thermosyphon cooling system used in HTS rotating machines  

NASA Astrophysics Data System (ADS)

The cooling systems used for rotating High-Temperature Superconducting (HTS) machines need a cooling power high enough to ensure a low temperature during various utilization states. Radiation, torque tube or current leads represent hundreds of watts of invasive heat. The architecture also has to allow the rotation of the refrigerant. In this paper, a free-convection thermosyphon using two Gifford-McMahon (GM) cryocoolers is presented. The cryogen is mainly neon but helium can be added for an increase of the heat transfer coefficient. The design of the heat exchangers was first optimized with FEM thermal analysis. After manufacture, they were assembled for preliminary experiments and the necessity of annealing was studied for the copper parts. A single evaporator was installed to evaluate the thermal properties of such a heat syphon. The maximum bearable static heat load was also investigated, but was not reached even at 150 W of load. Finally, this cooling system was tested in the cooling down of a 100-kW range HTS rotating machine containing 12 Bi-2223 double-pancake coils (DPC).

Felder, Brice; Miki, Motohiro; Tsuzuki, Keita; Shinohara, Nobuyuki; Hayakawa, Hironao; Izumi, Mitsuru

2012-06-01

335

Remagnetization effects due to lateral displacement above a PMG on bulk HTS magnet  

NASA Astrophysics Data System (ADS)

For a high-Tc superconducting (HTS) maglev system with large force requirements, the use of magnetized bulk high-Tc superconductor magnets (MBSCMs) is a good candidate because of its strong flux pinning ability and corresponding high trapped flux. Different from the rare-earth permanent magnet (PM), the trapped flux of a MBSCM is sustained by the supercurrent produced by a magnetizing process, so the trapped flux is sensitive to variations of the supercurrent. The lateral displacement of a MBSCM above a PM guideway (PMG) will provide disturbance of the applied field and then alter the supercurrent as a process of remagnetization. Different magnetization histories will bring different remagnetization characteristics and consequently diverse levitation performances for a MBSCM during the lateral displacements. When the MBSCMs are applied into the HTS maglev system, the influence of lateral displacements on levitation performance should be taken into consideration. This article investigates the remagnetization characteristics of a MBSCM when it is subject to the lateral displacements above a PMG with different trapped magnetic flux and opposite magnetization polarities. Relevant analyses about the internal supercurrent configuration based on the critical state model are also included to better understand the remagnetization characteristic of a MBSCM.

Liu, W.; Wang, J. S.; Ma, G. T.; Zheng, J.; Ren, J. F.; Li, L. L.; Yang, X. F.; Ye, C. Q.; Wang, S. Y.

2012-12-01

336

SpaceWire Data Handling Demonstration System  

NASA Astrophysics Data System (ADS)

The SpaceWire standard was published in 2003 with the aim of providing a standard for onboard communications, defining the physical and data link layers of an interconnection, in order to improve reusability, reliability and to reduce the cost of mission development. The many benefits which it provides mean that it has already been used in a number of missions, both in Europe and throughout the world. Recent work by the SpaceWire community has included the development of higher level protocols for SpaceWire, such as the Remote Memory Access Protocol (RMAP) which can be used for many purposes, including the configuration of SpaceWire devices. Although SpaceWire has become very popular, the various ways in which it can be used are still being discovered, as are the most efficient ways to use it. At the same time, some in the space industry are not even aware of SpaceWire's existence. This paper describes the SpaceWire Data Handling Demonstration System that has been developed by the University of Dundee. This system simulates an onboard data handling network based on SpaceWire. It uses RMAP for all communication, and so demonstrates how SpaceWire and standardised higher level protocols can be used onboard a spacecraft. The system is not only a good advert for those who are unfamiliar with the benefits of SpaceWire, it is also a useful tool for those using SpaceWire to test ideas.

Mills, S.; Parkes, S. M.; O'Gribin, N.

2007-08-01

337

Wire Crimp Connectors Verification using Ultrasonic Inspection  

NASA Technical Reports Server (NTRS)

The development of a new ultrasonic measurement technique to quantitatively assess wire crimp connections is discussed. The amplitude change of a compressional ultrasonic wave propagating through the junction of a crimp connector and wire is shown to correlate with the results of a destructive pull test, which previously has been used to assess crimp wire junction quality. Various crimp junction pathologies (missing wire strands, incorrect wire gauge, incomplete wire insertion in connector) are ultrasonically tested, and their results are correlated with pull tests. Results show that the ultrasonic measurement technique consistently (as evidenced with pull-testing data) predicts good crimps when ultrasonic transmission is above a certain threshold amplitude level. A physics-based model, solved by finite element analysis, describes the compressional ultrasonic wave propagation through the junction during the crimping process. This model is in agreement within 6% of the ultrasonic measurements. A prototype instrument for applying the technique while wire crimps are installed is also presented.

Cramer, K. Elliott; Perey, Daniel F.; Yost, William T.

2007-01-01

338

Parallel wire cable static load testing  

NASA Astrophysics Data System (ADS)

This report is the result of two evaluations for the analysis of parallel wire cables. The purpose of the first assessment was to evaluate the stiffness and strength of parallel wire cables. For the methodology, three test setups were executed utilizing single wires, seven wire parallel cables, and 100 wire parallel cables as specimens. The parallel wire cables were connected with molted zinc to their sockets. The cables were manufactured by Wilolamb Construction. The results indicate that the single, seven, and 100 wire specimens had similar performance in yield stress, yield strain, modulus, and ultimate strain. However, the amount of strain decreased as the number of wires increased. Because the mechanical properties of the multi wires specimens had not significant difference, it is suggested that the zinc sockets had insignificant impact on their performance. Comparing these results to a previous test executed for parallel wire cables, there were significant differences on the ultimate capacity. It is assumed that the fabrication method of the cables were different. The second evaluation had two purposes. First, it was intended to compare the results of the single wire test from OSU to the single wire test results from Sherry Laboratories. From the analysis, it was found that the ultimate and yield loads were similar between both laboratories procedures, but their strength capacity and ultimate strain were different. It was observed that the Sherry Lab used a different method to compute the mechanical properties of the wire and that the measurement of the elongation was different to the procedures from OSU. Second, the secondary analysis was to evaluate if there is any significant difference between wires sanded at the mid-length of the specimen and wires that were not sanded. From this analysis it was observed that there was no difference between the sanded and non-sanded wires, which indicated that cross-section reduction should not be necessary for the evaluation of multi wire cables. The results from this work were expected and agree with basic engineering principles, and that parallel wire cables are capable of performing as a group of wires with no significant losses.

Velasco Gil, Isabella C.

339

Sintered wire cesium dispenser photocathode  

DOEpatents

A photoelectric cathode has a work function lowering material such as cesium placed into an enclosure which couples a thermal energy from a heater to the work function lowering material. The enclosure directs the work function lowering material in vapor form through a low diffusion layer, through a free space layer, and through a uniform porosity layer, one side of which also forms a photoelectric cathode surface. The low diffusion layer may be formed from sintered powdered metal, such as tungsten, and the uniform porosity layer may be formed from wires which are sintered together to form pores between the wires which are continuous from the a back surface to a front surface which is also the photoelectric surface.

Montgomery, Eric J; Ives, R. Lawrence; Falce, Louis R

2014-03-04

340

Reduced-Wiring Tactile Sensor  

NASA Technical Reports Server (NTRS)

Proposed tactile sensor on robot finger puts out multiplexed analog signals transmitted to control computer on fewer wires than needed to transmit equivalent digital signals. Analog output represents data on contact area of object being gripped, on position of object, and on direction and rate of slippage if any. Consists of chains of normally open switches and resistors on surface of finger. Each resistance double preceding resistance in each chain. Constant-current sources supply power to chains.

Ohm, Timothy R.

1991-01-01

341

Pin Wire Coating Trip Report  

SciTech Connect

A meeting to discuss the current pin wire coating problems was held at the Reynolds plant in Los Angeles on 2MAR04. The attendance list for Reynolds personnel is attached. there was an initial presentation which gave a brief history and the current status of pin wire coating at Reynolds. There was a presentation by Lori Primus on the requirements and issues for the coating. There was a presentation by Jim Smith of LANL on the chemistry and to some extent process development done to date. There was a long session covering what steps should be taken in the short term and, to a lesser extent, the long term. The coating currently being used is a blend of two polymers, polyethersulfone and polyparabanic acid (PPA) and some TiO2 filler. This system was accepted and put into production when the pin wire coating was outsourced to another company in 1974. When that company no longer was interested, the wire coating was brought in-house to Reynolds. At that time polyparabanic acid was actually a commercial product available from Exxon under the trade name Tradlon. However, it appears that the material used at Reynolds was synthesized locally. Also, it appears that a single large batch was synthesized in that time period and used up to 1997 when the supply ran out. The reason for the inclusion of TiO2 is not known although it does act as a rheological thickener. However, a more controlled thickening can be obtained with materials such as fumed silica. This material would have less likelihood of causing point imperfections in the coatings. Also, the mixing technique being used for all stages of the process is a relatively low shear ball mill process and the author recommends a high shear process such as a three roll paint mill, at least for the final mixing. Since solvent is added to the powder at Reynolds, it may be that they need to have the paint mill there.

Spellman, G P

2004-03-18

342

Experimental Study of Counterflow Cooling Using a Test Loop to Simulate the Thermal Characteristics of a HTS Cable System  

SciTech Connect

The counterflow cooling configuration is a compact, efficient, and relatively low cost thermal management approach for long-length HTS cable systems. In the counter-flow cooling configuration the coolant flow, typically liquid nitrogen, is initially supplied through the center of the cable turning around at the far end of the cable and returning through the annular space between the cable and the inner cryostat wall, using a single cryostat. The temperature distributions along the cable and the nitrogen flow streams are extremely difficult to measure in an operating HTS cable because of the issues associated with installing thermometers on high voltage components. A 5-meter long test loop has been built that simulates a counter-flow cooled, HTS cable using a heated metal tube to simulate the cable. The test loop contains calibrated thermometers to measure the temperature distribution along the tube and the return liquid nitrogen stream. Measured temperature distributions in the return flow stream and along the tube wall for varying flow rates and heating conditions to simulate a HTS cable are presented and discussed.

Demko, Jonathan A [ORNL

2012-01-01

343

Design of 154 kV class 100 MVA 3 phase HTS transformer on a common magnetic core  

Microsoft Academic Search

We have proposed a high temperature superconducting (HTS) transformer which can substitute for a conventional oil transformer for power distribution in Korea. The conventional transformer is composed of three identical single phase transformers because of the limitations on volume and weight. Now the Korean power company has started to consider the possibility of a transformer on a common magnetic core

J. Choi; S. Lee; W. Kim; S. Kim; J. Han; H. Lee; K. Choi

2007-01-01

344

Design of 154 kV class 100 MVA 3 phase HTS transformer on a common magnetic core  

NASA Astrophysics Data System (ADS)

We have proposed a high temperature superconducting (HTS) transformer which can substitute for a conventional oil transformer for power distribution in Korea. The conventional transformer is composed of three identical single phase transformers because of the limitations on volume and weight. Now the Korean power company has started to consider the possibility of a transformer on a common magnetic core because it can be a solution for the increment of capacity without new construction of substations. In this paper, we proposed an HTS transformer on a common core. Its capacity is the same as the previous HTS transformer, which was 100 MVA, 154 kV/22.9 kV. The former is smaller and lighter than the latter. We assumed a transformer tank which covers the common core and windings. The tank also acts as a vacuum seal for a cooling system and so the cryostats for the windings do not need to have vacuum layers. The design parameters are compared with those of both a conventional one and an HTS transformer with separate cores.

Choi, J.; Lee, S.; Park, M.; Kim, W.; Kim, S.; Han, J.; Lee, H.; Choi, K.

2007-10-01

345

HigHligHts and BreaktHrougHs Pauling's rules, in a world of non-spherical atoms  

E-print Network

HigHligHts and BreaktHrougHs Pauling's rules, in a world of non-spherical atoms roBert t. downs tenet of Pauling's Rules, which is that atoms are spheres of a single fixed size.Their analysis provides, explains the older ones. Keywords: Electron density distribution, Paulings rules, non-spherical atoms Jerry

Downs, Robert T.

346

Profiling Environmental Chemicals in the Antioxidant Response Element Pathway using Quantitative High Throughput Screening (qHTS)  

EPA Science Inventory

The antioxidant response element (ARE) signaling pathway plays an important role in the amelioration of oxidative stress, which can contribute to a number of diseases, including cancer. We screened 1408 NTP-provided substances in 1536-well qHTS format at concentrations ranging fr...

347

The fundamental study to control the magnetic field for MDDS using shielding currents of HTS tapes and bulks  

NASA Astrophysics Data System (ADS)

The magnetic drug delivery system (MDDS) is a key technology to reduce the side effects in the medical applications, and the magnetic force control is a very important issue in MDDS. In general, the high magnetic field along the axial direction and high magnetic field gradient along the longitudinal direction are very useful for MDDS. So, we proposed the new magnetic force control system that consists of superconducting magnet, high temperature superconductors (HTS) bulks or tapes and ferromagnetic substances. In this new system, the shielding currents in HTS bulks and tapes due to diamagnetism of the superconductor generate the magnetic field with same direction of external magnetic field, and we can control the magnetic field gradient along the longitudinal direction by the arrangement of the HTS bulks, tapes and ferromagnetic substances. In this study, the stacked GdBCO tapes without stabilizer were used in experiments and electromagnetic analysis based on finite element method (FEM) was carried out to optimize the arrangement of the superconductors and the irons. It was confirmed that the control of magnetic field gradient along the longitudinal direction was possible by arranging the HTS bulks, tapes and irons on the superconducting magnet and then it was possible to obtain a magnetic field higher than the external field.

Kim, S. B.; Eritate, I.; Abe, T.; Shima, S.; Takahashi, M.

2014-11-01

348

Study on the Levitation and Restoring Force Characteristics of the Improved HTS-permanent Magnet Hybrid Magnetic Bearing  

NASA Astrophysics Data System (ADS)

We have developed the hybrid magnetic bearing using permanent magnets and high temperature bulk super conductor (HTS). In this system, the permanent magnet has ring type structure so that the permanent magnet and the HTS can be set to the stator. The pinning force of the HTS is used for the levitation and the guidance. Repulsive force of the permanent magnets was used in the conventional hybrid system. However the restoring force in the guidance direction of the conventional hybrid system decreases by the side slip force of the permanent magnets. In this research, attractive force of permanent magnets is used for increasing the load weight in the guidance direction. In this paper, influence of the hybrid system on the static characteristics of the rotor is studied. Three-dimensional numerical analysis of the linkage flux (in the levitation and the guidance direction) in the HTS is undertaken. The stator side permanent magnet increases the linkage flux of the levitation direction. Therefore in the hybrid system the linkage flux of the levitation direction increases. The levitation and restoring force of the rotor is measured. The levitation force of the hybrid system becomes smaller than that of the non-hybrid one by attractive force. The rotor in the hybrid system is supported by the pinning force and attractive force. The restoring force of the hybrid system becomes larger than that of the non-hybrid one because of increasing the linkage flux of the levitation direction.

Sugiyama, R.; Oguni, K.; Ohashi, S.

349

HTS and PCT Reliability of Chips and Flex Substrates Assembled Using a Thermosonic Flip-Chip Bonding Process  

NASA Astrophysics Data System (ADS)

This study assesses the high-temperature storage (HTS) test and the pressure-cooker test (PCT) reliability of an assembly of chips and flexible substrates. After the chips were bonded onto the flexible substrates, specimens were utilized to assess the HTS test and PCT reliability. After the PCT and HTS tests, the die-shear test was applied to examine changes in die-shear forces. The microstructure of the test specimens was analyzed to evaluate reliability and to identify possible failure mechanisms. When the duration of the HTS test was increased, the percentage of gold bumps that peeled off from the surface of the copper pads on the chip side increased, and a crack was present at the bonding interface between the gold bumps and chip bond pads. This crack was due to thermal stress generated during the HTS test, and degraded the die-shear force of the assembly of chips and flexible substrates. After the PCT, the crack was present at the interface between deposited layers of copper electrodes after the specimens were subjected to the PCT for various durations. Moisture penetrated into the deposited layers of the copper electrodes, deposited layers lost their adhesion, and the crack progressed from the corner into the central bond area as the test duration increased. To improve the PCT reliability of assemblies of chips and flexible substrates using the thermosonic flip-chip bonding process, one must prevent moisture from penetrating into deposited layers of copper electrodes and prevent crack formation at the interface between nickel and copper layers. Underfill would be an effective approach to prevent moisture from penetrating into deposited layers during the PCT, thereby improving the reliability of the samples during the PCT.

Chuang, Cheng-Li; Kang, Min-Yi

2012-09-01

350

The HTS barcode checker pipeline, a tool for automated detection of illegally traded species from high-throughput sequencing data  

PubMed Central

Background Mixtures of internationally traded organic substances can contain parts of species protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). These mixtures often raise the suspicion of border control and customs offices, which can lead to confiscation, for example in the case of Traditional Chinese medicines (TCMs). High-throughput sequencing of DNA barcoding markers obtained from such samples provides insight into species constituents of mixtures, but manual cross-referencing of results against the CITES appendices is labor intensive. Matching DNA barcodes against NCBI GenBank using BLAST may yield misleading results both as false positives, due to incorrectly annotated sequences, and false negatives, due to spurious taxonomic re-assignment. Incongruence between the taxonomies of CITES and NCBI GenBank can result in erroneous estimates of illegal trade. Results The HTS barcode checker pipeline is an application for automated processing of sets of 'next generation’ barcode sequences to determine whether these contain DNA barcodes obtained from species listed on the CITES appendices. This analytical pipeline builds upon and extends existing open-source applications for BLAST matching against the NCBI GenBank reference database and for taxonomic name reconciliation. In a single operation, reads are converted into taxonomic identifications matched with names on the CITES appendices. By inclusion of a blacklist and additional names databases, the HTS barcode checker pipeline prevents false positives and resolves taxonomic heterogeneity. Conclusions The HTS barcode checker pipeline can detect and correctly identify DNA barcodes of CITES-protected species from reads obtained from TCM samples in just a few minutes. The pipeline facilitates and improves molecular monitoring of trade in endangered species, and can aid in safeguarding these species from extinction in the wild. The HTS barcode checker pipeline is available at https://github.com/naturalis/HTS-barcode-checker. PMID:24502833

2014-01-01

351

Thermal energy scavenger (rotating wire modules)  

SciTech Connect

A thermal energy scavenger assembly is is described including a plurality of temperature-sensitive wires made of material which exhibits shape memory due to a thermoelastic, martensitic phase transformation. The wires are placed in tension between fixed and movable plates which are, in turn, supported by a pair of wheels which are rotatably supported by a housing for rotation about a central axis. A pair of upper and lower cams are fixed to the housing and cam followers react with the respective cams. Each cam transmits forces through a pair of hydraulic pistons. One of the pistons is connected to a movable plate to which one end of the wires are connected whereby a stress is applied to the wires to strain the wires during a first phase and whereby the cam responds to the unstraining of the wires during a second phase. A housing defines fluid compartments through which hot and cold fluid passes and flows radially through the wires whereby the wires become unstrained and shorten in length when subjected to the hot fluid for causing a reaction between the cam followers and the cams to effect rotation of the wheels about the central axis of the assembly, which rotation of the wheels is extracted through beveled gearing. The wires are grouped into a plurality of independent modules with each module having a movable plate, a fixed plate and the associated hydraulic pistons and cam follower. The hydraulic pistons and cam follower of a module are disposed at ends of the wires opposite from the ends of the wires at which the same components of the next adjacent modules are disposed so that the cam followers of alternate modules react with one of the cams and the remaining cam followers of the remaining modules react with the other cam. There is also included stress limiting means in the form of coil springs associated with alternate ends of the wires for limiting the stress or strain in the wires.

Hochstein, P.A.; Milton, H.W.; Pringle, W.L.

1980-11-04

352

A Vibrating Wire System For Quadrupole Fiducialization  

SciTech Connect

A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization step of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire position detectors. The tooling balls on the wire position detectors are finally related to tooling balls on the quadrupole to perform the fiducialization. The total 25 {micro}m fiducialization error must be divided between these three steps. The wire must be positioned onto the quadrupole magnetic axis to within 10 {micro}m, the wire position must be measured relative to tooling balls on the wire position detectors to within 15 {micro}m, and tooling balls on the wire position detectors must be related to tooling balls on the quadrupole to within 10 {micro}m. The techniques used in these three steps will be discussed. The note begins by discussing various quadrupole fiducialization techniques used in the past and discusses why the vibrating wire technique is our method of choice. We then give an overview of the measurement system showing how the vibrating wire is positioned onto the quadrupole axis, how the wire position detectors locate the wire relative to tooling balls without touching the wire, and how the tooling ball positions are all measured. The novel feature of this system is the vibrating wire which we discuss in depth. We analyze the wire dynamics and calculate the expected sensitivity of the system. The note should be an aid in debugging the system by providing calculations to compare measurements to.

Wolf, Zachary

2010-12-13

353

DC current distribution mapping system of the solar panels using a HTS-SQUID gradiometer  

NASA Astrophysics Data System (ADS)

Solar panels are expected to play a major role as a source of sustainable energy. In order to evaluate solar panels, non-destructive tests, such as defect inspections and response property evaluations, are necessary. We developed a DC current distribution mapping system of the solar panels using a High Critical Temperature Superconductor Superconducting Quantum Interference Device (HTS-SQUID) gradiometer with ramp edge type Josephson junctions. Two independent components of the magnetic fields perpendicular to the panel surface (?Bz/?x, ?Bz/?y) were detected. The direct current of the solar panel is visualized by calculating the composition of the two signal components, the phase angle, and mapping the DC current vector. The developed system can evaluate the uniformity of DC current distributions precisely and may be applicable for defect detection of solar panels.

Miyazaki, Shingo; Kasuya, Syohei; Mawardi Saari, Mohd; Sakai, Kenji; Kiwa, Toshihiko; Tsukamoto, Akira; Adachi, Seiji; Tanabe, Keiichi; Tsukada, Keiji

2014-05-01

354

Study on nondestructive inspection using HTS-SQUID for friction stir welding between dissimilar metals  

NASA Astrophysics Data System (ADS)

We have developed an SQUID-NDI technique for evaluation of friction stir welding (FSW) between aluminum alloy A6063 and stainless steel SUS304 from the electric conductivities in board specimens bonded by FSW. A SQUID-NDI system employing an HTS-SQUID gradiometer was constructed to measure current distribution in the FSW specimens by applying voltage to the specimen. By measuring field gradients d B z/d y and d B z/d x above the FSW specimens made with various FSW conditions and then converting them to current vector J x and J y, conductivities of FSW areas were estimated. Due to the difference in the FSW conditions, the conductivity distributions varied dramatically. From these results, it was suggested that the conductivities in FSW areas should be varied due to the temperature heated by the friction between the milling tool and the materials.

Hatsukade, Y.; Takahashi, T.; Yasui, T.; Tsubaki, M.; Fukumono, M.; Tanaka, S.

2007-10-01

355

Experimental Study on Current Decay Characteristics of Persistent Current HTS Magnet by Alternating Magnetic Field  

NASA Astrophysics Data System (ADS)

This paper deals with a current decay characteristics of a high temperature superconducting (HTS) magnet operated in persistent current mode (PCM). In superconducting synchronous machine applications such as linear synchronous motor (LSM), the superconducting coil is designed to operate in the PCM to obtain steady magnetic field with DC transport current. This superconducting magnet operates on a direct current, but it can be exposed to alternating magnetic field due to the armature winding. When the magnet is subjected to an external time-varying magnetic field, it is possible to result in a decay of the current in PCM system due to AC loss. In this research, a PCM system with armature coil which generates time-varying magnetic field was fabricated to verify current decay characteristics by external alternating magnetic field. The current decay rate was measured by using a hall sensor as functions of amplitude and frequency of armature coil.

Park, Young Gun; Lee, Chang Young; Hwang, Young Jin; Lee, Woo Seung; Lee, Jiho; Jo, Hyun Chul; Chung, Yoon Do; Ko, Tae Kuk

356

Materials basis for a six-level epitaxial HTS digital circuit process  

SciTech Connect

We have developed a process for fabrication of HTS single-flux-quantum logic circuits based on edge SNS junctions which requires six epitaxial film layers and six mask levels. The process was successfully applied to fabrication of small-scale circuits ({le} 10 junctions). This paper examines the materials properties affecting the reproducibility of YBCO-based SNS junctions, the low inductance provided by an integrated YBCO ground plane, and electrical isolation by SrTiO{sub 3} or SrAlTaO{sub 6} ground-plane and junction insulator layers. Some of the critical processing parameters identified by electrical measurements, TEM, SEM, and AFM were control of second-phase precipitates in YBCO, oxygen diffusion, Ar ion milling parameters, and preparation of surfaces for subsequent high-temperature depositions.

Talvacchio, J.; Forrester, M.G.; Hunt, B.D. [Northrop Grumman Science and Technology Center, Pittsburgh, PA (United States)] [and others

1996-12-31

357

Thermodynamic design of 10 kW Brayton cryocooler for HTS cable  

NASA Astrophysics Data System (ADS)

Thermodynamic design of Brayton cryocooler is presented as part of an ongoing governmental project in Korea, aiming at 1 km HTS power cable in the transmission grid. The refrigeration requirement is 10 kW for continuously sub-cooling liquid nitrogen from 72 K to 65 K. An ideal Brayton cycle for this application is first investigated to examine the fundamental features. Then a practical cycle for a Brayton cryocooler is designed, taking into account the performance of compressor, expander, and heat exchangers. Commercial software (Aspen HYSYS) is used for simulating the refrigeration cycle with real fluid properties of refrigerant. Helium is selected as a refrigerant, as it is superior to neon in thermodynamic efficiency. The operating pressure and flow rate of refrigerant are decided with a constraint to avoid the freezing of liquid nitrogen

Chang, Ho-Myung; Park, C. W.; Yang, H. S.; Sohn, Song Ho; Lim, Ji Hyun; Oh, S. R.; Hwang, Si Dole

2012-06-01

358

Electrical evaluation of the AC losses in a BSCCO cable with an HTS shield  

NASA Astrophysics Data System (ADS)

In general, a high temperature superconductor (HTS) cable has a conductor and a shield encircling it. This structure causes electrical evaluation of AC loss in the HTS cable to be very difficult. Thus it is not clear yet. Using two voltage leads attached to the conductor and shield, respectively, we evaluated not only their AC loss but also the cable’s total loss. To experimentally elucidate our electrical evaluation presented in this work, first we measured the total loss of the 100 m/22.9 kV BSCCO cable by calorimetry, especially around 77 K. Besides the same 5 m cable sample as above, another cable model with a thin insulator was also tested electrically, and they were compared with two numerical models: a non-twisted polygon model and a twisted cylinder model. The results show that, according to the insulator thickness between a conductor and a shield, their magnetic interaction becomes very different. For the 100 and 5 m cables, their normalized total AC losses measured from calorimetry and electrical evaluation correspond well to each other, regardless of operating temperatures. Moreover, the numerical analysis shows that the total AC losses measured for the 5 m sample and cable model fit with the numerically calculated ones. Besides, the conductor’s AC losses measured for both the cables agree well with the numerical ones, regardless of their insulator thickness. This is because a conductor in an actual cable is inside a shield, and so does not receive any effect of the shield’s magnetic field. These experimental and theoretical results support the view that our electrical evaluation for the total and conductor losses is reliable. However, unlike the results for the total and conductor losses, the shield’s experimental loss is not in good agreement with any of the theoretical ones from either the non-twisted polygon model or the twisted cylinder model.

Ryu, K.; Li, Z. Y.; Hwang, S. D.

2014-02-01

359

250 kW flywheel with HTS magnetic bearing for industrial use  

NASA Astrophysics Data System (ADS)

A 250 kW / 5 kWh engineering prototype Flywheel Energy Storage System (FESS) was designed, fabricated and component tested by Adelwitz Technologiezentrum GmbH (ATZ) and L-3 Communications Magnet - Motor GmbH (MM). A heavy - load vertical 0.6 ton rotor is suspended totally magnetically by an HTS radial-passive bearing on the top together with a PM bearing at the bottom. Further features are the flywheel rotor body which is manufactured from carbon fibre reinforced plastics (CFRP) in a multi-rim version and combined with an integrated high-power motor/generator. A 35 W/77 K single- stage Gifford McMahon cryo-cooler is cooling the HTS bearing to a temperature of 45 - 60 K. Functionality and efficiency of the magnetic bearing configurations, rotor control concepts and motor / generator power electric system is considered and established. Bearing stiffness parameters, damping performance, and rotational friction are measured. Testing of further components under vacuum conditions confirmed that low bearing drag and wear- free operation can be attained. The motor-generator operates with a power in excess of 250 kW and an efficiency of > 92%, including the losses of the inverters. A redundant mechanical touchdown bearing system can be activated to restore the rotor position. The separately tested flywheel components are now in the assembling status expecting first machine tests in November 2007. After studying and measuring all FESS parameters in -house the dynamical storage device will be tested in a German E.ON power station under industrial conditions.

Werfel, F. N.; Floegel-Delor, U.; Riedel, T.; Rothfeld, R.; Wippich, D.; Goebel, B.; Reiner, G.; Wehlau, N.

2008-02-01

360

The thrombolytic action of a proteolytic fraction (P1G10) from Carica candamarcensis.  

PubMed

A group of cysteine-proteolytic enzymes from C. candamarcensis latex, designated as P1G10 displays pharmacological properties in animal models following various types of lesions. This enzyme fraction expresses in vitro fibrinolytic effect without need for plasminogen activation. Based on this evidence, we assessed by intravital microscopy the effect of P1G10 on recanalization of microvessels after thrombus induction in the ear of hairless mice. Video playback of intravital microscopic images allowed measurement of blood flow velocity (mm/s) during the experimental procedure. Groups treated with 5 or 7.5mg/Kg P1G10 showed thrombolysis between 7-15min, without vessel obstruction. Ex vivo experiments demonstrated that platelet activation by ADP is impaired in a dose dependent manner following treatment with P1G10. The P1G10 action on plasma coagulation also showed that prothrombin time (PT), thrombin time (TT) and activated partial thromboplastin time (aPTT, ?g/uL) are increased in a dose dependent manner. In addition, P1G10 displayed fibrinogenolytic and fibrinolytic activities, both in a dose dependent manner. Each of these effects was suppressed by inhibition of the proteolytic activity of the fraction. The antithrombotic action of P1G10 can be explained by proteolytic cleavage of fibrinogen and fibrin, both key factors during formation of a stable thrombus. These results combined with prior evidence suggest that P1G10 has potential as thrombolytic agent. PMID:23473638

Bilheiro, Rogério P; Braga, Ariadne D; Filho, Marcelo Limborço; Carvalho-Tavares, Juliana; Agero, Ubirajara; Carvalho, Maria das Graças; Sanchez, Eladio F; Salas, Carlos E; Lopes, Miriam T P

2013-04-01

361

Induced EMF in a coil of wire  

NSDL National Science Digital Library

Students use a simple set up consisting of a coil of wire and a magnet to visualize induced EMF. First, students move a coil of wire near a magnet and observe the voltage that results. They then experiment with moving the wire, magnet, and a second, current carrying coil. Students connect the coil to a circuit and the current from the induced EMF charges a conductor.

VU Bioengineering RET Program, School of Engineering,

362

Space Shuttle Columbia Aging Wiring Failure Analysis  

NASA Technical Reports Server (NTRS)

A Space Shuttle Columbia main engine controller 14 AWG wire short circuited during the launch of STS-93. Post-flight examination divulged that the wire had electrically arced against the head of a nearby bolt. More extensive inspection revealed additional damage to the subject wire, and to other wires as well from the mid-body of Columbia. The shorted wire was to have been constructed from nickel-plated copper conductors surrounded by the polyimide insulation Kapton, top-coated with an aromatic polyimide resin. The wires were analyzed via scanning electron microscope (SEM), energy dispersive X-Ray spectroscopy (EDX), and electron spectroscopy for chemical analysis (ESCA); differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) were performed on the polyimide. Exemplar testing under laboratory conditions was performed to replicate the mechanical damage characteristics evident on the failed wires. The exemplar testing included a step test, where, as the name implies, a person stepped on a simulated wire bundle that rested upon a bolt head. Likewise, a shear test that forced a bolt head and a torque tip against a wire was performed to attempt to damage the insulation and conductor. Additionally, a vibration test was performed to determine if a wire bundle would abrade when vibrated against the head of a bolt. Also, an abrasion test was undertaken to determine if the polyimide of the wire could be damaged by rubbing against convolex helical tubing. Finally, an impact test was performed to ascertain if the use of the tubing would protect the wire from the strike of a foreign object.

McDaniels, Steven J.

2005-01-01

363

Wire frame to MOVIE. BYU transfer program  

SciTech Connect

At SNLA, the primary computer-aided drafting tool is the Applicon Graphics System (AGS). The data base for mechanical parts on the AGS is a wire frame model. This report summarizes a method of adding surface information to the wire frame and passing this information up stream to MOVIE.BYU which is on a VAX computer and is used to produce shaded graphics pictures of the AGS wire frame model on a RAMTEK 9400 display terminal.

Robbins, D.; Byers, L.D.; Benner, M.S.

1982-12-01

364

Early excitability changes in lumbar motoneurons of transgenic SOD1G85R and SOD1G(93A-Low) mice.  

PubMed

This work characterizes the properties of wild-type (WT) mouse motoneurons in the second postnatal week and compares these at the same age and in the same conditions to those of two different SOD1 mutant lines used as models of human amyotrophic lateral sclerosis (ALS), the SOD1(G93A) low expressor line and SOD1(G85R) line, to describe any changes in the functional properties of mutant motoneurons (Mns) that may be related to the pathogenesis of human ALS. We show that very early changes in excitability occur in SOD1 mutant Mns that have different properties from those of WT animals. The SOD1(G93A-Low) low expressor line displays specific differences that are not found in other mutant lines including a more depolarized membrane potential, larger spike width, and slower spike rise slope. With current pulses SOD1(G93A-Low) were hyperexcitable, but both mutants had a lower gain with current ramps stimulation. Changes in the threshold and intensities of Na(+) and Ca(2+) persistent inward currents were also observed. Low expressor mutants show reduced total persistant inward currents compared with WT motoneurons in the same recording conditions and give arguments toward modifications of the balance between Na(+) and Ca(2+) persistent inward currents. During the second week postnatal, SOD1(G93A-Low) lumbar motoneurons appear more immature than those of SOD1(G85R) compared with WT and we propose that different time course of the disease, possibly linked with different toxic properties of the mutated protein in each model, may explain the discrepancies between excitability changes described in the different models. PMID:19828728

Pambo-Pambo, Arnaud; Durand, Jacques; Gueritaud, Jean-Patrick

2009-12-01

365

Superconducting-wire fabrication. Final report  

SciTech Connect

Experiments were done leading to the fabrication of high-temperature superconducting composite wire. Bulk superconductor was characterized by using optical microscopy, scanning electron microscopy, and energy-dispersive x-ray spectroscopy. The chemical compatibility of superconducting materials with a number of metal sheathing candidates was tested, with silver offering the best compatibility. Wire was fabricated by drawing 0.250-inch-diameter silver tubing packed with superconducting powder. Single core wires were drawn to 0.037-inch diameter. The best critical current performance (660 A/cm2) for leaded bismuth 2-2-2-3 material was achieved by flattening single-core wire before heat treatment.

Glad, W.E.; Chase, G.G.

1990-05-01

366

Wired.  

ERIC Educational Resources Information Center

Discusses technology's impact on scoreboard design: the development of the light-emitting diode (LED) display. How the LED system works is explained, as are the advantages and disadvantages of LED compared with incandescent lamp boards. Final comments address deciding on materials for scoreboard casings. (GR)

Conklin, Aaron R.

1998-01-01

367

Processing A Printed Wiring Board By Single Bath Electrodeposition  

DOEpatents

A method of processing a printed wiring board by single bath electrodeposition. Initial processing steps are implemented on the printed wiring board. Copper is plated on the printed wiring board from a bath containing nickel and copper. Nickel is plated on the printed wiring board from the bath containing nickel and copper and final processing steps are implemented on the printed wiring board.

Meltzer, Michael P. (Oakland, CA); Steffani, Christopher P. (Livermore, CA); Gonfiotti, Ray A. (Livermore, CA)

2003-04-15

368

Processing a printed wiring board by single bath electrodeposition  

DOEpatents

A method of processing a printed wiring board. Initial processing steps are implemented on the printed wiring board. Copper is plated on the printed wiring board from a bath containing nickel and copper. Nickel is plated on the printed wiring board from a bath containing nickel and copper and final processing steps are implemented on the printed wiring board.

Meltzer, Michael P. (Oakland, CA); Steffani, Christopher P. (Livermore, CA); Gonfiotti, Ray A. (Livermore, CA)

2010-12-07

369

Joule heating of solid wires in MAG welding  

Microsoft Academic Search

There are numerous studies concerning the melting rate of welding wire and various investigations have been carried out on welding current, welding current waveform, wire extension, polarity, chemical composition, wire diameter, arc length, shielding gas composition and melting rate. Joule heating of bulk wire has been a large contributory factor to the melting rate of solid wire for carbon steel

H. Shimizu; Y. Yokota; T. Itoh; T. Kurokawa; M. Ushio

2005-01-01

370

Corner error simulation of rough cutting in wire EDM  

Microsoft Academic Search

This paper describes a novel simulation method for wire electrical discharge machining (EDM) in corner cut of rough cutting. In the simulation system, we analyzed the wire electrode vibration due to the reaction force acting on the wire electrode during the wire EDM, set up a geometrical model between the wire electrode path and NC path, and investigated the relationship

Fuzhu Han; Jie Zhang; Isago Soichiro

2007-01-01

371

Application of medium frequency atmospheric plasma on continuous aluminum wire cleaning for magnet wire manufacturing  

Microsoft Academic Search

Recently, the study on the application of atmospheric plasma treatment has gradually increased because it requires high cost vacuum systems, and the flexibility of application to a continuous process. This paper reports on the new application of medium frequency atmospheric plasma to the continuous surface cleaning of aluminum wire for magnet wire manufacturing. Magnet wire is widely used for transformers

In S Choi; Seok W Hwang; Jong C Park

2001-01-01

372

The Effect of Cutting Parameters on Wire Crater Sizes in Wire EDM  

Microsoft Academic Search

In this study, the effect of the cutting parameters on size of erosion craters (diameter and depth) on wire electrode were experimentally and theoretically investigated in wire electrical discharge machining (WEDM). The experiments were conducted under the different cutting parameters of pulse duration (300, 500, 700, and 900 ns), open circuit voltage (80, 100, and 270 V), wire speed (5,

N. Tosun; H. Pihtili

2003-01-01

373

An industrial application for on-line detection of instability and wire breakage in wire EDM  

Microsoft Academic Search

One of the main challenges in wire electrical discharge machining (WEDM) is avoiding wire breakage and unstable situations as both phenomena reduce process performance and can cause low quality components. This work proposes a methodology that guarantees an early detection of instability that can be used to avoid the detrimental effects associated to both unstable machining and wire breakage. The

I. Cabanes; E. Portillo; M. Marcos; J. A. Sánchez

2008-01-01

374

An improved lead wire compensation technique for conventional four wire resistance temperature detectors (RTDs)  

Microsoft Academic Search

A new lead wire compensation technique is presented for conventional four wire resistance temperature detectors (RTDs). Existing four wire resistance temperature detectors generally use bridge balance technique to achieve balance and unbalance bridge output is calibrated in terms of unknown temperature. Out of the four leads, two leads are connected to one arm of the bridge while the other two

S. K. Sen; T. K. Pan; P. Ghosal

2011-01-01

375

Mechanism of Thickness Dependence of Critical Current Density in HTS YBaCuO7-x Film and Its Elimination Using Nano-Engineering  

E-print Network

The most promising characteristic of a High Temperature Superconductor (HTS) is its ability to carry larger electrical current at liquid nitrogen boiling temperature and strong applied magnetic field with minimal dissipation. Numerous large scale...

Wang, Xiang

2008-01-01

376

Tuning a Tetrahertz Wire Laser  

NASA Technical Reports Server (NTRS)

Tunable terahertz lasers are desirable in applications in sensing and spectroscopy because many biochemical species have strong spectral fingerprints at terahertz frequencies. Conventionally, the frequency of a laser is tuned in a similar manner to a stringed musical instrument, in which pitch is varied by changing the length of the string (the longitudinal component of the wave vector) and/ or its tension (the refractive index). However, such methods are difficult to implement in terahertz semiconductor lasers because of their poor outcoupling efficiencies. Here, we demonstrate a novel tuning mechanism based on a unique 'wire laser' device for which the transverse dimension w is much much less than lambda. Placing a movable object close to the wire laser manipulates a large fraction of the waveguided mode propagating outside the cavity, thereby tuning its resonant frequency. Continuous single-mode redshift and blueshift tuning is demonstrated for the same device by using either a dielectric or metallic movable object. In combination, this enables a frequency tuning of approximately equal to 137 GHz (3.6%) from a single laser device at approximately equal to 3.8 THz.

Qin, Qi; Williams, Benjamin S.; Kumar, Sushil; Reno, John L.; Hu, Qing

2009-01-01

377

Improved Superconducting Wire for Wind Generators: Superconducting Wires for Direct-Drive Wind Generators  

SciTech Connect

REACT Project: Brookhaven National Laboratory will develop a low-cost superconducting wire that could be used in high-power wind generators. Superconducting wire currently transports 600 times more electric current than a similarly sized copper wire, but is significantly more expensive. Brookhaven National Laboratory will develop a high-performance superconducting wire that can handle significantly more electrical current, and will demonstrate an advanced manufacturing process that has the potential to yield a several-fold reduction in wire costs while using a using negligible amount of rare earth material. This design has the potential to make a wind turbine generator lighter, more powerful, and more efficient, particularly for offshore applications.

None

2012-01-01

378

Experimental Study of the Normal Zone Propagation Velocity in Double-layer 2G-HTS wires by Thermal and Electrical Methods  

E-print Network

dissipated by the liquid nitrogen close to the heater may become smaller than in the area further away (See Fig. 5), as the cooling power of liquid nitrogen is not monotonic with temperature [14] Moreover, we have noticed that the distinct signature... labelled as Tc1 to Tc3, and the power chip resistor (heater). various cryogenic conditions, and typical results are given ranging from 5 mm/s to 20 mm/s for different applied current [3, 4, 6-9]. However, according to our knowledge, not many studies...

Zhong, Z.; Ruiz, H. S.; Lai, L.; Huang, Z.; Wang, W.; Coombs, T.

2014-11-20

379

Wiring harnesses documented by punched-card technique  

NASA Technical Reports Server (NTRS)

Cards representing a connector are punched, sorted, and then used to printout wiring documentation for that connector. When wiring changes are made, new cards are punched and the wiring documentation is reprinted to reflect the latest configuration.

Hicks, W. W.; Kloezeman, W. G.

1970-01-01

380

30 CFR 75.1430 - Wire ropes; scope.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Wire ropes; scope. 75.1430 Section 75.1430 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...MINES Hoisting and Mantrips Wire Ropes § 75.1430 Wire ropes; scope. (a) Sections 75.1430...

2010-07-01

381

47 CFR 32.2321 - Customer premises wiring.  

Code of Federal Regulations, 2010 CFR

...account shall include all amounts transferred from the former Account 232, Station Connections, inside wiring subclass. (b) Embedded Customer Premises Wiring is that investment in customer premises wiring equipment or inventory which was capitalized...

2010-10-01

382

46 CFR 28.865 - Wiring methods and materials.  

Code of Federal Regulations, 2011 CFR

... Wiring methods and materials. 28.865 Section... Wiring methods and materials. (a) All cable...replacement wiring, new cabling and/or alterations...chapter. (f) All metallic cable armor must be...Representative. Any new installation,...

2011-10-01

383

46 CFR 28.865 - Wiring methods and materials.  

Code of Federal Regulations, 2013 CFR

... Wiring methods and materials. 28.865 Section... Wiring methods and materials. (a) All cable...replacement wiring, new cabling and/or alterations...chapter. (f) All metallic cable armor must be...Representative. Any new installation,...

2013-10-01

384

46 CFR 28.865 - Wiring methods and materials.  

Code of Federal Regulations, 2012 CFR

... Wiring methods and materials. 28.865 Section... Wiring methods and materials. (a) All cable...replacement wiring, new cabling and/or alterations...chapter. (f) All metallic cable armor must be...Representative. Any new installation,...

2012-10-01

385

46 CFR 28.865 - Wiring methods and materials.  

Code of Federal Regulations, 2014 CFR

... Wiring methods and materials. 28.865 Section... Wiring methods and materials. (a) All cable...replacement wiring, new cabling and/or alterations...chapter. (f) All metallic cable armor must be...Representative. Any new installation,...

2014-10-01

386

30 CFR 56.12053 - Circuits powered from trolley wires.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12053 Circuits powered from trolley wires. Ground wires for lighting circuits powered from trolley wires...

2010-07-01

387

30 CFR 56.12053 - Circuits powered from trolley wires.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12053 Circuits powered from trolley wires. Ground wires for lighting circuits powered from trolley wires...

2011-07-01

388

30 CFR 56.12053 - Circuits powered from trolley wires.  

Code of Federal Regulations, 2012 CFR

...DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56.12053 Circuits powered from trolley wires. Ground wires for lighting circuits powered from trolley wires...

2012-07-01

389

Stiffness Corrections for the Vibration Frequency of a Stretched Wire  

ERIC Educational Resources Information Center

Discusses the need of introducing corrections due to wire stiffness arising from end constraints and wire axis distribution curvature in the measurement of ac electrical frequency by exciting transverse standing waves in a stretched steel wire. (SL)

Hornung, H. G.; Durie, M. J.

1977-01-01

390

Wire ageing with the TEA photocathode  

SciTech Connect

Recently several RICH protypes successfully tested a gaseous TEA photocathode. However, its wire ageing behavior is unknown. In principle, TEA is a more strongly bonded molecule than TMAE, and, as a result, one would expect better wire ageing behavior. This paper explores this question.

Va`vra, J.

1996-06-01

391

Wire-antenna designs using genetic algorithms  

Microsoft Academic Search

There is a large class of electromagnetic radiators designated as wire antennas. As a rule, an inductive process is used to design these antennas. Either an integral equation is formulated or a simulator is used that gives the current distributions on the wires of the antenna, from which the electromagnetic properties of the antenna can then be determined. Once the

Edward E. Altshuler; Derek S. Linden

1997-01-01

392

Diamond tools for wire sawing metal components  

Microsoft Academic Search

In the last few years, a wire sawing process has been developed for many applications in the field of natural stone and construction materials, especially for very thick materials or components that are difficult to access. Diamond wire cutting was limited to small carbon-steel shapes, such as pipelines for transporting gas or oil under the sea. In particular, the task

H. K. Tönshoff; H. Hillmann-Apmann

2002-01-01

393

Superconducting wire with improved strain characteristics  

DOEpatents

A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improves the strain characteristics of the wire.

Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (E. Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

1982-01-01

394

Superconducting wire with improved strain characteristics  

DOEpatents

A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improve the strain characteristics of the wire.

Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (East Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

1982-01-01

395

LANSCE-R WIRE-SCANNER SYSTEM  

SciTech Connect

The National Instruments cRIO platform is used for the new LANSCE-R wire-scanner systems. All wire-scanner electronics are integrated into a single BiRa BiRIO 4U cRIO chassis specifically designed for the cRIO crate and all interface electronics. The BiRIO chassis, actuator and LabVIEW VIs provide a complete wire-scanner system integrated with EPICS. The new wire-scanner chassis includes an 8-slot cRIO crate with Virtex-5 LX 110 FPGA and Power-PC real-time controller, the LANL-developed cRIO 2-axis wire-sensor analog interface module (AFE), NI9222 cRIO 4-channel 16-bit digitizer, cRIO resolver demodulator, cRIO event receiver, front-panel touch panel display, motor driver, and all necessary software, interface wiring, connectors and ancillary components. This wirescanner system provides a complete, turn-key, 2-axis wire-scanner system including 2-channel low-noise sensewire interface with variable DC wire bias and wireintegrity monitor, 16-bit signal digitizers, actuator motor drive and control, actuator position sensing, limit-switch interfaces, event receiver, LabVIEW and EPICS interface, and both remote operation and full stand-alone operation using the touch panel.

Gruchalla, Michael E. [Los Alamos National Laboratory

2011-01-01

396

Ultrasonic aluminum wire bonding. Final report  

SciTech Connect

An aluminum wire bonding process was developed. Techniques were developed for bonding large diameter wire to a power transistor and evaporated gold. Bond schedules were made to be used in producing hybrid microcircuits. Calibration techniques utilizing an elctromagnetic transducer to measure tool movement proved successful. The magnetic transducer is best suited as a trouble-shooting tool.

Sim, J.R.

1980-09-01

397

Microfabricated wire arrays for Z-pinch.  

SciTech Connect

Microfabrication methods have been applied to the fabrication of wire arrays suitable for use in Z. Self-curling GaAs/AlGaAs supports were fabricated as an initial route to make small wire arrays (4mm diameter). A strain relief structure that could be integrated with the wire was designed to allow displacements of the anode/cathode connections in Z. Electroplated gold wire arrays with integrated anode/cathode bus connections were found to be sufficiently robust to allow direct handling. Platinum and copper plating processes were also investigated. A process to fabricate wire arrays on any substrate with wire thickness up to 35 microns was developed. Methods to handle and mount these arrays were developed. Fabrication of wire arrays of 20mm diameter was demonstrated, and the path to 40mm array fabrication is clear. With some final investment to show array mounting into Z hardware, the entire process to produce a microfabricated wire array will have been demonstrated.

Spahn, Olga Blum; Rowen, Adam M.; Cich, Michael Joseph; Peake, Gregory Merwin; Arrington, Christian L.; Nash, Thomas J.; Klem, John Frederick; Romero, Dustin Heinz

2008-10-01

398

Lansce Wire Scanning Diagnostics Device Mechanical Design  

SciTech Connect

The Accelerator Operations & Technology Division at Los Alamos National Laboratory operates a linear particle accelerator which utilizes 110 wire scanning diagnostics devices to gain position and intensity information of the proton beam. In the upcoming LANSCE improvements, 51 of these wire scanners are to be replaced with a new design, up-to-date technology and off-the-shelf components. This document outlines the requirements for the mechanical design of the LANSCE wire scanner and presents the recently developed linac wire scanner prototype. Additionally, this document presents the design modifications that have been implemented into the fabrication and assembly of this first linac wire scanner prototype. Also, this document will present the design for the second, third, and fourth wire scanner prototypes being developed. Prototypes 2 and 3 belong to a different section of the particle accelerator and therefore have slightly different design specifications. Prototype 4 is a modification of a previously used wire scanner in our facility. Lastly, the paper concludes with a plan for future work on the wire scanner development.

Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Batygin, Yuri K. [Los Alamos National Laboratory; Gilpatrick, John D. [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Maestas, Alfred J. [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Raybun, Joseph L. [Los Alamos National Laboratory; Sattler, F. D. [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

2011-01-01

399

Simple Fatigue Machine for Wires and Foils  

Microsoft Academic Search

A simple fatigue machine suitable for testing wires, filaments, foils, and other specimens of small cross section has been designed and built. The axial-load machine applies an alternating stress about a tensile mean stress and is of the constant amplitude of force type utilizing electromagnetic loading. One data curve for commercially pure titanium wire is presented to demonstrate the performance

R. L. Benedetti; D. L. Creighton

1970-01-01

400

Temperature Dependent Wire Delay Estimation in Floorplanning  

E-print Network

Temperature Dependent Wire Delay Estimation in Floorplanning Andreas Thor Winther, Wei Liu, Alberto, Arizona State University, Tempe, USA Abstract--Due to large variations in temperature in VLSI cir- cuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length

Nannarelli, Alberto

401

Wire-Guide Manipulator For Automated Welding  

NASA Technical Reports Server (NTRS)

Compact motor drive positions guide for welding filler wire. Drive part of automated wire feeder in partly or fully automated welding system. Drive unit contains three parallel subunits. Rotations of lead screws in three subunits coordinated to obtain desired motions in three degrees of freedom. Suitable for both variable-polarity plasma arc welding and gas/tungsten arc welding.

Morris, Tim; White, Kevin; Gordon, Steve; Emerich, Dave; Richardson, Dave; Faulkner, Mike; Stafford, Dave; Mccutcheon, Kim; Neal, Ken; Milly, Pete

1994-01-01

402

Underwater Electrical Wire Explosion and Its Applications  

Microsoft Academic Search

Results of an investigation of underwater electrical wire explosions using high-power microsecond and nanosecond generators are reported. Different diagnostics, including electrical, optical, and spectroscopic, together with hydrodynamic and magnetohydrodynamic simulations, were used to characterize parameters of the discharge channel and generated strong shock waves. It was shown that the increase in the rate of the energy input into exploding wire

Yakov E. Krasik; Alon Grinenko; Arkady Sayapin; Sergey Efimov; Alexander Fedotov; Viktor Z. Gurovich; Vladimir I. Oreshkin

2008-01-01

403

Effects of turn-to-turn compactness in the straight sections of HTS racetrack coils on thermal and electrical characteristics  

NASA Astrophysics Data System (ADS)

The thermal and electrical characteristics of two GdBCO-coated conductor racetrack coils, one insulated with Kapton insulation and the other without turn-to-turn insulation, were investigated by typical voltage-current measurement, charge-discharge, sudden discharge, and over-current tests with respect to external pressures applied to the straight sections of the coils. The test results show that the thermal and electrical stabilities of the racetrack coil without insulation were enhanced considerably with increasing external pressure up to 0.5 MPa, whereas those of the insulated coil were not affected by the pressure. The non-insulated HTS racetrack-type coil with improved turn-to-turn thermal contact in the straight sections may have the potential to be manufactured into field coils for HTS wind turbine generators with highly enhanced thermal and electrical stabilities.

Kwon, O. J.; Kim, K. L.; Choi, Y. H.; Shin, H. J.; Hahn, S.; Iwasa, Y.; Lee, H. G.

2013-08-01

404

PAINS in the Assay: Chemical Mechanisms of Assay Interference and Promiscuous Enzymatic Inhibition Observed during a Sulfhydryl-Scavenging HTS  

PubMed Central

Significant resources in early drug discovery are spent unknowingly pursuing artifacts and promiscuous bioactive compounds, while understanding the chemical basis for these adverse behaviors often goes unexplored in pursuit of lead compounds. Nearly all the hits from our recent sulfhydryl-scavenging high-throughput screen (HTS) targeting the histone acetyltransferase Rtt109 were such compounds. Herein, we characterize the chemical basis for assay interference and promiscuous enzymatic inhibition for several prominent chemotypes identified by this HTS, including some pan-assay interference compounds (PAINS). Protein mass spectrometry and ALARM NMR confirmed these compounds react covalently with cysteines on multiple proteins. Unfortunately, compounds containing these chemotypes have been published as screening actives in reputable journals and even touted as chemical probes or preclinical candidates. Our detailed characterization and identification of such thiol-reactive chemotypes should accelerate triage of nuisance compounds, guide screening library design, and prevent follow-up on undesirable chemical matter. PMID:25634295

2015-01-01

405

Study - Radiation Shielding Effectiveness of the Prototyped High Temperature Superconductivity (HTS) 'Artificial' Magnetosphere for Deep Space Missions  

NASA Technical Reports Server (NTRS)

The high temperature superconductor (HTS) is being used to develop the magnets for the Variable Specific Impulse Magneto-plasma Rocket (VASIMR ) propulsion system and may provide lightweight magnetic radiation shielding to protect spacecraft crews from radiation caused by GCR and SPEs on missions to Mars. A study is being planned to assess the radiation shielding effectiveness of the artificial magnetosphere produced by the HTS magnet. VASIMR is an advanced technology propulsion engine which is being touted as enabling one way transit to Mars in 90 days or less. This is extremely important to NASA. This technology would enable a significant reduction in the number of days in transit to and from Mars and significantly reduce the astronauts exposure to a major threat - high energy particles from solar storms and GCR during long term deep space missions. This paper summarizes the plans for the study and the subsequent testing of the VASIMR technology onboard the ISS slated for 2013.

Denkins, Pamela

2010-01-01

406

Wire and Cable Cold Bending Test  

NASA Technical Reports Server (NTRS)

One of the factors in assessing the applicability of wire or cable on the lunar surface is its flexibility under extreme cold conditions. Existing wire specifications did not address their mechanical behavior under cold, cryogenic temperature conditions. Therefore tests were performed to provide this information. To assess this characteristic 35 different insulated wire and cable pieces were cold soaked in liquid nitrogen. The segments were then subjected to bending and the force was recorded. Any failure of the insulation or jacketing was also documented for each sample tested. The bending force tests were performed at room temperature to provide a comparison to the change in force needed to bend the samples due to the low temperature conditions. The results from the bending tests were plotted and showed how various types of insulated wire and cable responded to bending under cold conditions. These results were then used to estimate the torque needed to unroll the wire under these low temperature conditions.

Colozza, Anthony

2010-01-01

407

Method of preparing composite superconducting wire  

DOEpatents

An improved method of preparing composite multifilament superconducting wire of Nb.sub.3 Sn in a copper matrix which eliminates the necessity of coating the drawn wire with tin. A generalized cylindrical billet of an alloy of copper containing at least 15 weight percent niobium, present in the copper as discrete, randomly distributed and oriented dendritic-shaped particles, is provided with at least one longitudinal opening which is filled with tin to form a composite drawing rod. The drawing rod is then drawn to form a ductile composite multifilament wire containing a filament of tin. The ductile wire containing the tin can then be wound into magnet coils or other devices before heating to diffuse the tin through the wire to react with the niobium forming Nb.sub.3 Sn. Also described is an improved method for making large billets of the copper-niobium alloy by consumable-arc casting.

Verhoeven, John D. (Ames, IA); Gibson, Edwin D. (Ames, IA); Finnemore, Douglas K. (Ames, IA); Ostenson, Jerome E. (Ames, IA); Schmidt, Frederick A. (Ames, IA); Owen, Charles V. (Ames, IA)

1985-08-06

408

Electronic transport in inhomogeneous quantum wires.  

SciTech Connect

We study the transport properties of a long non-uniform quantum wire where the electron-electron interactions and the density vary smoothly at large length scales. We show that these inhomogeneities lead to a finite resistivity of the wire, due to a weak violation of momentum conservation in the collisions between electrons. Estimating the rate of change of momentum associated with non-momentum-conserving scattering processes, we derive the expression for the resistivity of the wire in the regime of weakly interacting electrons and find a contribution linear in temperature for a broad range of temperatures below the Fermi energy. By estimating the energy dissipated throughout the wire by low-energy excitations, we then develop a different method for deriving the resistivity of the wire, which can be combined with the bosonization formalism. This allows us to compare our results with previous works relying on an extension of the Tomonaga-Luttinger model to inhomogeneous systems.

Rech, J.; Matveev, K. A.; Materials Science Division

2008-04-23

409

Wiring Damage Analyses for STS OV-103  

NASA Technical Reports Server (NTRS)

This study investigated the Shuttle Program s belief that Space Transportation System (STS) wiring damage occurrences are random, that is, a constant occurrence rate. Using Problem Reporting and Corrective Action (PRACA)-derived data for STS Space Shuttle OV-103, wiring damage was observed to increase over the vehicle s life. Causal factors could include wiring physical deterioration, maintenance and inspection induced damage, and inspection process changes resulting in more damage events being reported. Induced damage effects cannot be resolved with existent data. Growth analysis (using Crow-AMSAA, or CA) resolved maintenance/inspection effects (e.g., heightened awareness) on all wire damages and indicated an overall increase since Challenger Return-to-Flight (RTF). An increasing failure or occurrence rate per flight cycle was seen for each wire damage mode; these (individual) rates were not affected by inspection process effects, within statistical error.

Thomas, Walter, III

2006-01-01

410

Effect of Surface Quality of Brass Coating Wire on Wire EDM Characteristics  

NASA Astrophysics Data System (ADS)

The purpose of this study is to develop a new type of wire electrode, in which piano wire with very high tensile strength is coated with electrically conductive layer, such as brass or zinc, in order to attain high speed and high precision wire EDM. In this report, using a trial-made thin wire of 50?m in diameter, the optimum thickness and quality of brass layer were experimentally investigated for higher performance fine wire EDM. Furthermore, the influence of the tensile strength of piano wire used as a core wire was discussed. As a result, the coated brass with copper content of 60-70% is effective and the thickness of coated brass is needed to be more than 1.45?m for high removal rate.

Okada, Akira; Yamauchi, Toshiyuki; Arizono, Kimihiko; Uno, Yoshiyuki

411

Novel Patient Cell-Based HTS Assay for Identification of Small Molecules for a Lysosomal Storage Disease  

PubMed Central

Small molecules have been identified as potential therapeutic agents for lysosomal storage diseases (LSDs), inherited metabolic disorders caused by defects in proteins that result in lysosome dysfunctional. Some small molecules function assisting the folding of mutant misfolded lysosomal enzymes that are otherwise degraded in ER-associated degradation. The ultimate result is the enhancement of the residual enzymatic activity of the deficient enzyme. Most of the high throughput screening (HTS) assays developed to identify these molecules are single-target biochemical assays. Here we describe a cell-based assay using patient cell lines to identify small molecules that enhance the residual arylsulfatase A (ASA) activity found in patients with metachromatic leukodystrophy (MLD), a progressive neurodegenerative LSD. In order to generate sufficient cell lines for a large scale HTS, primary cultured fibroblasts from MLD patients were transformed using SV40 large T antigen. These SV40 transformed (SV40t) cells showed to conserve biochemical characteristics of the primary cells. Using a specific colorimetric substrate para-nitrocatechol sulfate (pNCS), detectable ASA residual activity were observed in primary and SV40t fibroblasts from a MLD patient (ASA-I179S) cultured in multi-well plates. A robust fluorescence ASA assay was developed in high-density 1,536-well plates using the traditional colorimetric pNCS substrate, whose product (pNC) acts as “plate fluorescence quencher” in white solid-bottom plates. The quantitative cell-based HTS assay for ASA generated strong statistical parameters when tested against a diverse small molecule collection. This cell-based assay approach can be used for several other LSDs and genetic disorders, especially those that rely on colorimetric substrates which traditionally present low sensitivity for assay-miniaturization. In addition, the quantitative cell-based HTS assay here developed using patient cells creates an opportunity to identify therapeutic small molecules in a disease-cellular environment where potentially disrupted pathways are exposed and available as targets. PMID:22216298

Ribbens, Jameson; Zheng, Wei; Southall, Noel; Hu, Xin; Marugan, Juan J.; Ferrer, Marc; Maegawa, Gustavo H. B.

2011-01-01

412

Detection of early stage damage in carbon fiber reinforced polymers for aeronautical applications using an HTS SQUID magnetometer  

Microsoft Academic Search

.  We present an experimental characterization of \\u000amultidirectional fibre composites based on eddy current testing using HTS dc \\u000aSQUID (Superconducting Quantum Interference Device) magnetometers. The \\u000acorrelation between the mechanical tolerance of CFRPs with different \\u000athickness and the phase gradient of the magnetic field generated by damage \\u000ais shown. The eddy current based SQUID NDE is used to detect damage not \\u000avisible

C. Bonavolontà; G. Peluso; G. P. Pepe; M. Valentino

2004-01-01

413

Excited singlet molecular O2 (1?g) is generated enzymatically from excited carbonyls in the dark  

PubMed Central

In mammalian tissues, ultraweak chemiluminescence arising from biomolecule oxidation has been attributed to the radiative deactivation of singlet molecular oxygen [O2 (1?g)] and electronically excited triplet carbonyl products involving dioxetane intermediates. Herein, we describe evidence of the generation of O2 (1?g) in aqueous solution via energy transfer from excited triplet acetone. This involves thermolysis of 3,3,4,4-tetramethyl-1,2-dioxetane, a chemical source, and horseradish peroxidase-catalyzed oxidation of 2-methylpropanal, as an enzymatic source. Both sources of excited carbonyls showed characteristic light emission at 1,270?nm, directly indicative of the monomolecular decay of O2 (1?g). Indirect analysis of O2 (1?g) by electron paramagnetic resonance using the chemical trap 2,2,6,6-tetramethylpiperidine showed the formation of 2,2,6,6-tetramethylpiperidine-1-oxyl. Using [18O]-labeled triplet, ground state molecular oxygen [18O2 (3?g-)], chemical trapping of 18O2 (1?g) with disodium salt of anthracene-9,10-diyldiethane-2,1-diyl disulfate yielding the corresponding double-[18O]-labeled 9,10-endoperoxide, was detected through mass spectrometry. This corroborates formation of O2 (1?g). Altogether, photoemission and chemical trapping studies clearly demonstrate that chemically and enzymatically nascent excited carbonyl generates 18O2 (1?g) by triplet-triplet energy transfer to ground state oxygen O2 (3?g?), and supports the long formulated hypothesis of O2 (1?g) involvement in physiological and pathophysiological events that might take place in tissues in the absence of light. PMID:25087485

Mano, Camila M.; Prado, Fernanda M.; Massari, Júlio; Ronsein, Graziella E.; Martinez, Glaucia R.; Miyamoto, Sayuri; Cadet, Jean; Sies, Helmut; Medeiros, Marisa H. G.; Bechara, Etelvino J. H.; Di Mascio, Paolo

2014-01-01

414

Lack of Association of the APOL1 G3 Haplotype in African Americans with ESRD.  

PubMed

Apolipoprotein L1 gene (APOL1) G1 and G2 variants are strongly associated with progressive nondiabetic nephropathy in populations with recent African ancestry. Selection for these variants occurred as a result of protection from human African trypanosomiasis (HAT). Resequencing of this region in 10 genetically and geographically distinct African populations residing in HAT endemic regions identified eight single nucleotide polymorphisms (SNPs) in strong linkage disequilibrium and comprising a novel G3 haplotype. To determine whether the APOL1 G3 haplotype was associated with nephropathy, G1, G2, and G3 SNPs and 70 ancestry informative markers spanning the genome were genotyped in 937 African Americans with nondiabetic ESRD, 965 African Americans with type 2 diabetes-associated ESRD, and 1029 non-nephropathy controls. In analyses adjusting for age, sex, APOL1 G1/G2 risk (recessive), and global African ancestry, the G3 haplotype was not significantly associated with ESRD (P=0.05 for nondiabetic ESRD, P=0.57 for diabetes-associated ESRD, and P=0.27 for all-cause ESRD). We conclude that variation in APOL1 G3 makes a nominal, if any, contribution to ESRD in African Americans; G1 and G2 variants explain the vast majority of nondiabetic nephropathy susceptibility. PMID:25249559

Palmer, Nicholette D; Ng, Maggie C Y; Langefeld, Carl D; Divers, Jasmin; Lea, Janice P; Okusa, Mark D; Kimberly, Robert P; Bowden, Donald W; Freedman, Barry I

2014-09-23

415

B1 ?u+ and EF1 ?g+ level energies of D2  

NASA Astrophysics Data System (ADS)

Accurate absolute level energies of the B1 ?u+, v = 0-8, N and EF1 ?g+, v = 0-21, N rovibrational quantum states of molecular deuterium are derived by combining results from a Doppler-free two-photon laser excitation study on several lines in the EF1 ?g+ - X1 ?g+ (0, 0) band, with results from a Fourier-transform spectroscopic emission study on a low-pressure hydrogen discharge. Level energy uncertainties as low as 0.0005 cm-1 are obtained for some low-lying E1 ?g+ inner-well rovibrational levels, while uncertainties for higher-lying rovibrational levels and those of the F1 ?g+ outer-well states are nominally 0.005 cm-1. Level energies of B1 ?u+ rovibrational levels, for v ? 8 and N ? 10 are determined at an accuracy of 0.001 cm-1. Computed wavelengths of D2 Lyman transitions in the B1 ?u+- X1 ?g+ (v, 0) bands are also tabulated for future applications.

Salumbides, E. J.; Bailly, D.; Vervloet, M.; Ubachs, W.

2014-11-01

416

In Situ Electrochemical Deposition of Microscopic Wires  

NASA Technical Reports Server (NTRS)

A method of fabrication of wires having micron and submicron dimensions is built around electrochemical deposition of the wires in their final positions between electrodes in integrated circuits or other devices in which the wires are to be used. Heretofore, nanowires have been fabricated by a variety of techniques characterized by low degrees of controllability and low throughput rates, and it has been necessary to align and electrically connect the wires in their final positions by use of sophisticated equipment in expensive and tedious post-growth assembly processes. The present method is more economical, offers higher yields, enables control of wire widths, and eliminates the need for post-growth assembly. The wires fabricated by this method could be used as simple electrical conductors or as transducers in sensors. Depending upon electrodeposition conditions and the compositions of the electroplating solutions in specific applications, the wires could be made of metals, alloys, metal oxides, semiconductors, or electrically conductive polymers. In this method, one uses fabrication processes that are standard in the semiconductor industry. These include cleaning, dry etching, low-pressure chemical vapor deposition, lithography, dielectric deposition, electron-beam lithography, and metallization processes as well as the electrochemical deposition process used to form the wires. In a typical case of fabrication of a circuit that includes electrodes between which microscopic wires are to be formed on a silicon substrate, the fabrication processes follow a standard sequence until just before the fabrication of the microscopic wires. Then, by use of a thermal SiO-deposition technique, the electrodes and the substrate surface areas in the gaps between them are covered with SiO. Next, the SiO is electron-beam patterned, then reactive-ion etched to form channels having specified widths (typically about 1 m or less) that define the widths of the wires to be formed. Drops of an electroplating solution are placed on the substrate in the regions containing the channels thus formed, then the wires are electrodeposited from the solution onto the exposed portions of the electrodes and into the channels. The electrodeposition is a room-temperature, atmospheric-pressure process. The figure shows an example of palladium wires that were electrodeposited into 1-mm-wide channels between gold electrodes.

Yun, Minhee; Myung, Nosang; Vasquez, Richard

2005-01-01

417

Isotropic round-wire multifilament cuprate superconductor for generation of magnetic fields above 30 T  

NASA Astrophysics Data System (ADS)

Magnets are the principal market for superconductors, but making attractive conductors out of the high-temperature cuprate superconductors (HTSs) has proved difficult because of the presence of high-angle grain boundaries that are generally believed to lower the critical current density, Jc. To minimize such grain boundary obstacles, HTS conductors such as REBa2Cu3O7-x and (Bi, Pb)2Sr2Ca2Cu3O10-x are both made as tapes with a high aspect ratio and a large superconducting anisotropy. Here we report that Bi2Sr2CaCu2O8-x (Bi-2212) can be made in the much more desirable isotropic, round-wire, multifilament form that can be wound or cabled into arbitrary geometries and will be especially valuable for high-field NMR magnets beyond the present 1 GHz proton resonance limit of Nb3Sn technology. An appealing attribute of this Bi-2212 conductor is that, being without macroscopic texture, it contains many high-angle grain boundaries but nevertheless attains a very high Jc of 2,500 A mm-2 at 20 T and 4.2 K. The large potential of the conductor has been demonstrated by building a small coil that generated almost 2.6 T in a 31 T background field. This demonstration that grain boundary limits to high Jc can be practically overcome underlines the value of a renewed focus on grain boundary properties in non-ideal geometries.

Larbalestier, D. C.; Jiang, J.; Trociewitz, U. P.; Kametani, F.; Scheuerlein, C.; Dalban-Canassy, M.; Matras, M.; Chen, P.; Craig, N. C.; Lee, P. J.; Hellstrom, E. E.

2014-04-01

418

Wire tension monitor for proportional chambers of the ANKE spectrometer  

NASA Astrophysics Data System (ADS)

A high accuracy wire tension monitor for wire detectors has been developed. The tension is deduced from the wire mechanical resonance frequency. The resonance frequency is measured in the electrostatic excitation mode of wire oscillation. The Sensor converts the wire capacitance into a voltage which is analyzed in process of searching for the wire resonance frequency. The solution of the equation of forced wire oscillation is presented and analyzed in detail to improve accuracy of the wire tension measurement. The monitor has been used for testing multiwire proportional chambers of the ANKE spectrometer at COSY. It allows the wire tension to be measured with an accuracy of 0.7% which meets most requirements of the wire detectors. The possibility of the wire aging diagnostics at tension measurement is considered.

Volkov, A. D.

2013-02-01

419

LANSCE wire scanning diagnostics device mechanical design  

SciTech Connect

The Los Alamos Neutron Science Center (LANSCE) is one of the major experimental science facilities at the Los Alamos National Laboratory (LANL). The core of LANSCE's work lies in the operation of a powerful linear accelerator, which accelerates protons up to 84% the speed oflight. These protons are used for a variety of purposes, including materials testing, weapons research and isotopes production. To assist in guiding the proton beam, a series of over one hundred wire scanners are used to measure the beam profile at various locations along the half-mile length of the particle accelerator. A wire scanner is an electro-mechanical device that moves a set of wires through a particle beam and measures the secondary emissions from the resulting beam-wire interaction to obtain beam intensity information. When supplemented with data from a position sensor, this information is used to determine the cross-sectional profile of the beam. This measurement allows beam operators to adjust parameters such as acceleration, beam steering, and focus to ensure that the beam reaches its destination as effectively as possible. Some of the current wire scanners are nearly forty years old and are becoming obsolete. The problem with current wire scanners comes in the difficulty of maintenance and reliability. The designs of these wire scanners vary making it difficult to keep spare parts that would work on all designs. Also many of the components are custom built or out-dated technology and are no longer in production.

Rodriguez Esparza, Sergio [Los Alamos National Laboratory

2010-01-01

420

Wire Crimp Termination Verification Using Ultrasonic Inspection  

NASA Technical Reports Server (NTRS)

The development of a new ultrasonic measurement technique to quantitatively assess wire crimp terminations is discussed. The amplitude change of a compressional ultrasonic wave propagating through the junction of a crimp termination and wire is shown to correlate with the results of a destructive pull test, which is a standard for assessing crimp wire junction quality. Various crimp junction pathologies such as undercrimping, missing wire strands, incomplete wire insertion, partial insulation removal, and incorrect wire gauge are ultrasonically tested, and their results are correlated with pull tests. Results show that the nondestructive ultrasonic measurement technique consistently (as evidenced with destructive testing) predicts good crimps when ultrasonic transmission is above a certain threshold amplitude level. A physics-based model, solved by finite element analysis, describes the compressional ultrasonic wave propagation through the junction during the crimping process. This model is in agreement within 6% of the ultrasonic measurements. A prototype instrument for applying this technique while wire crimps are installed is also presented. The instrument is based on a two-jaw type crimp tool suitable for butt-splice type connections. Finally, an approach for application to multipin indenter type crimps will be discussed.

Perey, Daniel F.; Cramer, K. Elliott; Yost, William T.

2007-01-01

421

Evaluation of joint interface of friction stir welding between dissimilar metals using HTS-SQUID gradiometer  

NASA Astrophysics Data System (ADS)

In this study, we investigated conductive properties of joint interfaces of friction stir welding (FSW) between dissimilar metals, stainless steel SUS304 and aluminum A6063, using a SQUID nondestructive evaluation (NDE) system. With current injection method, the current maps above the FSW specimens jointed under various conditions were measured by a HTS-SQUID gradiometer. The conductivities of the joint interfaces, which were estimated from the current maps, differed between the joint conditions. By destructive tests using optical microscope, large voids were observed on the joint interfaces with low welding speed that generated excess heating. In case of one specimen, which was welded with welding speed of 500 and 200 mm/min, the conductivity of the former was higher than that of the latter, although the inside voids in the respective regions were not much different. From these results, it is suggested that the current maps were influenced not only by the conductivity of the joint interface but also by inside voids. By hardness test on the SUS boards near the interfaces, only the SUS jointed with 200 mm/min was about half softer than its matrix.

Mashiko, Y.; Hatsukade, Y.; Yasui, T.; Takenaka, H.; Todaka, Y.; Fukumoto, M.; Tanaka, S.

2010-11-01

422

Mechanical and electric characteristics of vacuum impregnated no-insulation HTS coil  

NASA Astrophysics Data System (ADS)

For the conduction cooling application, epoxy impregnation is inevitable to enhance the thermal conduction. However, there have been several research results on the delamination problem with coated conductor and the main cause of the delamination is related with the different thermal contraction between epoxy, the insulation layer and the weak conductor. To avoid this problem, the amount of epoxy and insulation layer between conductors should be minimized or removed. Therefore, no insulation (NI) winding method and impregnation after dry winding can be considered to solve the problem. The NI coil winding method is very attractive due to high mechanical/thermal stability for the special purpose of DC magnets by removing the insulation layer. In this paper, the NI coil winding method and vacuum impregnation are applied to a HTS coil to avoid the delamination problem and enhance the mechanical/thermal stability for the conduction cooling application. Through the charging/discharging operation, electric/thermal characteristics are investigated at 77 K and 30 K.

Park, Heecheol; Kim, A.-rong; Kim, Seokho; Park, Minwon; Kim, Kwangmin; Park, Taejun

2014-09-01

423

Thermosyphon Cooling System for the Siemens 400kW HTS Synchronous Machine  

NASA Astrophysics Data System (ADS)

A commercial GM cryocooler is employed to cool the rotor of the first Siemens 400 kW HTS machine. Excellent thermal connection between cold head and rotor is achieved using a thermosyphon. At the rotor's inner surface the required cooling power is provided by evaporating fluid, that is recondensed at the coldhead. Our configuration allows an easy mechanical decoupling of the stationary cold head and the rotor, using a magnetic liquid rotary seal. In order to shorten cool-down time, a precool to 70 K is done with a thermosyphon filling of nitrogen, while a motor operating temperature of 25 K is reached using neon. Temperature difference between the thermosyphon's cold and warm ends is below 1 K for a heat transfer of 40 W. During operation, a temperature controller stabilizes condenser temperature and hence rotor temperature. The self-regulating cooling system has been operated continuously and without problems since Spring 2001. The machine was also operated with newly developed pulse-tube cryocoolers, that are in development to take benefit of their expected prolonged service intervals.

Frank, M.; Frauenhofer, J.; Gromoll, B.; van Haßelt, P.; Nick, W.; Nerowski, G.; Neumüller, H.-W.; Häfner, H.-U.; Thummes, G.

2004-06-01

424

Results of the test of a pair of 20 kA HTS currents leads  

NASA Astrophysics Data System (ADS)

A new series connected 25 T hybrid magnet system is being set up by the Helmholtz Zentrum Berlin (HZB) for neutron scattering experiments. CRPP has designed and manufactured a pair of 20 kA current leads for the powering of the outer superconducting coils of the hybrid magnet system. In connection with the test of joints for JT60SA, the current leads were tested at ENEA at low voltage up to a current of 18 kA. The mass flow rates required to cool the current leads at different currents measured in the test are in line with the design calculations. For the sum of the resistances of the warm and cold end copper contacts of the HTS module values of 13 (Lead A) and 11 n? (Lead B) were measured. In addition, the helium flow through the heat exchanger part was stopped at 10 and 12 kA to study the behaviour of the current leads in case of a loss of flow. The time elapsed between stopping of the helium mass flow and the initiation of a quench was found to be 117 s (Lead A) and 125 s (Lead B) compared to a calculated value of 86 s. The lower value obtained by the calculation can be attributed to the lower initial temperatures in the experiment.

Wesche, R.; Bruzzone, P.; Fiamozzi Zignani, C.; Affinito, L.; Chiarelli, S.; Freda, R.; Formichetti, A.; Marchetti, M.; Ehmler, H.; Heinrich, J.; Smeibidl, P.

2014-05-01

425

Analysis of the anisotropic critical current behaviour of HTS coated conductors  

NASA Astrophysics Data System (ADS)

In order to generate fields of more than 20 T using pure superconducting magnets, the implementation of HTS coated conductors (CCs) is an option. Amongst the characteristics of the REBCO is its intrinsic anisotropy which means its critical current, Ic, varies as a function of its orientation with respect to the external magnetic field, phi, as well as being dependent on external field, B, and temperature, T. For the design of the high field insert coils for the experimental magnet facility HOMER II, the behaviour of Ic at fields of about 24 T and at phi approximately 80 ° is required. Within our JUMBO facility it is possible to measure the U(I) behaviour of commercial CCs at liquid helium and liquid nitrogen temperatures. The free bore available is 100 mm at 4.2 K; the applied magnetic field can be varied up to 10 T, and phi can be set between 0 and 180 °. Measurements were carried out on commercially available CCs with emphasis on phi values near to 90 °. The critical current was determined by means of a power law function fitted to the resulting U(I) curves using specially written Matlab® programs. A number of different three dimensional functions were fitted to the measurement data and compared with each other.

Leys, P. M.; Klaeser, M.; Schleissinger, F.; Schneider, Th

2014-05-01

426

Dynamic simulation of 10 kW Brayton cryocooler for HTS cable  

NASA Astrophysics Data System (ADS)

Dynamic simulation of a Brayton cryocooler is presented as a partial effort of a Korean governmental project to develop 1˜3 km HTS cable systems at transmission level in Jeju Island. Thermodynamic design of a 10 kW Brayton cryocooler was completed, and a prototype construction is underway with a basis of steady-state operation. This study is the next step to investigate the transient behavior of cryocooler for two purposes. The first is to simulate and design the cool-down process after scheduled or unscheduled stoppage. The second is to predict the transient behavior following the variation of external conditions such as cryogenic load or outdoor temperature. The detailed specifications of key components, including plate-fin heat exchangers and cryogenic turbo-expanders are incorporated into a commercial software (Aspen HYSYS) to estimate the temporal change of temperature and flow rate over the cryocooler. An initial cool-down scenario and some examples on daily variation of cryocooler are presented and discussed, aiming at stable control schemes of a long cable system.

Chang, Ho-Myung; Park, Chan Woo; Yang, Hyung Suk; Hwang, Si Dole

2014-01-01

427

Stirling-type pulse tube refrigerator with slit-type heat exchangers for HTS superconducting motor  

NASA Astrophysics Data System (ADS)

A cryogenic refrigeration system is one of the indispensable components for cooling superconducting motor or generator. Among various configurations of cryogenic refrigeration system, the on-board refrigeration system is considered to be attractive for compactness and small heat leak. In order to turn this concept into reality, we focus on two essential points; development of the specific structure for on-board refrigeration and optimal design of the refrigerator. Since the on-board refrigeration system should not create unbalanced vibration, the inline Stirling-type pulse tube refrigerator is considered as a good candidate and more concrete and efficient structure is developed under the design constraints. The dynamic absorber is used to maintain the dynamic stability of the single acting linear compressor. To increase thermal Carnot efficiency with the on-board Stirling-type pulse tube refrigerator, slit-type heat exchangers are implemented and flow straighteners are carefully designed by the three-dimensional CFD simulation. The overall configuration of the Stirling-type pulse tube refrigerator is designed and fabricated by the optimal process. The present on-board refrigerator has the cooling capacity of 7 W at 59.5 K with the Carnot efficiency of 10.9%. According to these experimental results, the pulse tube refrigerator as the on-board refrigeration system possesses a sufficient thermal efficiency despite the restricted design configuration. The on-board refrigeration is considered as a useful method for cooling HTS superconducting motor.

Ki, Taekyung; Jeong, Sangkwon

2011-06-01

428

Degradation Behavior of the HTS Bulk Magnet in Cryocooler System with Cyclic Temperature Variation  

NASA Astrophysics Data System (ADS)

This paper presents a change of magnetic flux trapped in the YBCO bulk magnet under thermal excursions. We have supposed a new cryocooler system for the high temperature superconducting(HTS) bulk magnet in which the thermal cycles are generated. From the past research, it was found that the trapped flux mainly deteriorated at the first temperature rise, but a large change of the trapped flux was not seen at the first temperature descent and following thermal cycles. Degradation of the trapped flux by the first temperature-rise was explained by using the bean model. Moreover we proposed the model which does not have a current distribution constant. In this paper, we examined a change of magnetic field in each part of the bulk in detail. In addition, we applied attention to the change of the trapped flux after the first temperature rise. Although there is no big change of the trapped flux after the first temperature-rise, it is decreasing slowly. This cause is considered as influence of the flux creep, but its decay is more rapid than usual.

Okuno, K.; Sawa, K.; Iwasa, Y.

2006-03-01

429

In-Situ Wire Damage Detection System  

NASA Technical Reports Server (NTRS)

An In-Situ Wire Damage Detection System (ISWDDS) has been developed that is capable of detecting damage to a wire insulation, or a wire conductor, or to both. The system will allow for realtime, continuous monitoring of wiring health/integrity and reduce the number of false negatives and false positives while being smaller, lighter in weight, and more robust than current systems. The technology allows for improved safety and significant reduction in maintenance hours for aircraft, space vehicles, satellites, and other critical high-performance wiring systems for industries such as energy production and mining. The integrated ISWDDS is comprised of two main components: (1) a wire with an innermost core conductor, an inner insulation film, a conductive layer or inherently conductive polymer (ICP) covering the inner insulation film, an outermost insulation jacket; and (2) smart connectors and electronics capable of producing and detecting electronic signals, and a central processing unit (CPU) for data collection and analysis. The wire is constructed by applying the inner insulation films to the conductor, followed by the outer insulation jacket. The conductive layer or ICP is on the outer surface of the inner insulation film. One or more wires are connected to the CPU using the smart connectors, and up to 64 wires can be monitored in real-time. The ISWDDS uses time domain reflectometry for damage detection. A fast-risetime pulse is injected into either the core conductor or conductive layer and referenced against the other conductor, producing transmission line behavior. If either conductor is damaged, then the signal is reflected. By knowing the speed of propagation of the pulse, and the time it takes to reflect, one can calculate the distance to and location of the damage.

Williams, Martha; Roberson, Luke; Tate, Lanetra; Smith, Trent; Gibson, Tracy; Medelius, Pedro; Jolley, Scott

2012-01-01

430

Total recall: an update on orthodontic wires.  

PubMed

Orthodontic therapy is a force management procedure largely based on use of arch wires for storing and distributing biologically tolerable forces by means of which position of teeth is altered. Advances in material science and technology has resulted in an array of newer arch wire materials, opening new vistas, in orthodontic treatment. Materials with widely diverging properties are in the market today and their usage has profound implications on appliance mechanics, and are very much different from stainless steel which is popular even today. The dentists who practise orthodontics have to therefore clearly outline the phases of treatment and select the arch wire most suited for attaining specific treatment goals. PMID:25745725

Jyothikiran, H; Shantharaj, Ravi; Batra, Panchali; Subbiah, Pradeep; Lakshmi, Bhagya; Kudagi, Vishal

2014-01-01

431

Space Station Freedom secondary power wiring requirements  

NASA Technical Reports Server (NTRS)

Secondary power is produced by DDCU's (direct current to direct current converter units) and routed to and through secondary power distribution assemblies (SPDA's) to loads or tertiary distribution assemblies. This presentation outlines requirements of Space Station Freedom (SSF) EEE (electrical, electronic, and electromechanical) parts wire and the approved electrical wire and cable. The SSF PDRD (Program Definition and Requirements Document) language problems and resolution are reviewed. The cable routing to and from the SPDA's is presented as diagrams and the wire recommendations and characteristics are given.

Sawyer, C. R.

1994-01-01

432

Detectors Ensure Function, Safety of Aircraft Wiring  

NASA Technical Reports Server (NTRS)

Pedro Medelius waited patiently in his lab at Kennedy Space Center. He had just received word that a colleague was bringing over a cable from a Space Shuttle solid rocket booster to test Medelius new invention. Medelius was calm until his colleague arrived, with about 30 other people. "Talk about testing under pressure," says Medelius. "There were people there from the Navy, the Air Force, and the Federal Aviation Administration." After the group s arrival, Medelius took a deep breath and connected his Standing Wave Reflectometer (SWR) to the cable. He wiggled the cable around, and the display showed a fault (a short or open circuit in wire) about an inch and a half inside the connector on the cable. His colleague questioned the results, because he had already checked that area on the cable. Medelius used the SWR to check again but got the same result. "That is when we took the cable apart and looked inside," Medelius says. "Lo and behold, that was exactly where the fault was." The impetus for Medelius new wire inspection technology came about in 1999 when one of the space shuttles lost power due to a fault somewhere in its more than 200 miles of electrical wiring. "The backup circuit was activated and prevented a major dysfunction, but nevertheless, there was a problem with the wiring," Medelius describes. Even though technicians used a device called a multimeter to measure the electrical current to find which wire had a fault, it could not pinpoint exactly where on the wire the fault was located. For that, technicians had to visually inspect the wire. "Sometimes they would have to remove the whole wire assembly and visually inspect every single wire. It was a very tedious operation because the wires are behind cabinets. They go all over the place in the shuttle," says Medelius. "NASA needed an instrument capable of telling them exactly where the faults were occurring." To meet NASA s needs for a highly precise device to inspect electrical power bundles, wires, and connectors, Medelius devised the SWR. "It came down to what was affected when a wire is short circuited or opened," he says. "We worked out a few equations based on physical principles." The SWR proved very sensitive, and the technology was patented.

2013-01-01

433

Copper Wire Bonding Concerns and Best Practices  

NASA Astrophysics Data System (ADS)

Copper wire bonding of microelectronic parts has developed as a means to cut the costs of using the more mature technology of gold wire bonding. However, with this new technology, changes in the bonding processes as well as bonding metallurgy can affect product reliability. This paper discusses the challenges associated with copper wire bonding and the solutions that the industry has been implementing. The paper also provides information to enable customers to conduct qualification and reliability tests on microelectronic packages to facilitate adoption in their target applications.

Chauhan, Preeti; Zhong, Z. W.; Pecht, Michael

2013-08-01

434

Plastic Deformation of 2D Crumpled Wires  

E-print Network

When a single long piece of elastic wire is injected trough channels into a confining two-dimensional cavity, a complex structure of hierarchical loops is formed. In the limit of maximum packing density, these structures are described by several scaling laws. In this paper it is investigated this packing process but using plastic wires which give origin to completely irreversible structures of different morphology. In particular, it is studied experimentally the plastic deformation from circular to oblate configurations of crumpled wires, obtained by the application of an axial strain. Among other things, it is shown that in spite of plasticity, irreversibility, and very large deformations, scaling is still observed.

M A F Gomes; V P Brito; A S O Coelho; C C Donato

2008-11-17

435

Telephone wire is backbone of security system  

SciTech Connect

Video provides a variety of low-cost, high-quality solutions in today`s security environment. Cost-conscious managers of power generation stations, casinos, prison facilities, military bases and office buildings are considering using regular telephone wire (unshielded twisted pair-UTP) within their existing systems as the backbone of a video to the PC, personal and video-conferencing and training are other areas where phone wire in a building can save money and provide an alternative to coax or fiber for video. More and more, businesses and government agencies are meeting their needs efficiently by using telephone wires for more than just telephones.

Brede, K.; Rackson, L.T.

1995-09-01

436

Summary of AH-1G flight vibration data for validation of coupled rotor-fuselage analyses  

NASA Technical Reports Server (NTRS)

Under a NASA research program designated DAMVIBS (Design Analysis Methods for VIBrationS), four U. S. helicopter industry participants (Bell Helicopter, Boeing Vertol, McDonnell Douglas Helicopter, and Sikorsky Aircraft) are to apply existing analytical methods for calculating coupled rotor-fuselage vibrations of the AH-1G helicopter for correlation with flight test data from an AH-1G Operational Load Survey (OLS) test program. Bell Helicopter, as the manufacturer of the AH-1G, was asked to provide pertinent rotor data and to collect the OLS flight vibration data needed to perform the correlations. The analytical representation of the fuselage structure is based on a NASTRAN finite element model (FEM) developed by Bell which has been extensively documented and correlated with ground vibration tests.The AH-1G FEM was provided to each of the participants for use in their coupled rotor-fuselage analyses. This report describes the AH-1G OLS flight test program and provides the flight conditions and measured vibration data to be used by each participant in their correlation effort. In addition, the mechanical, structural, inertial and aerodynamic data for the AH-1G two-bladed teetering main rotor system are presented. Furthermore, modifications to the NASTRAN FEM of the fuselage structure that are necessary to make it compatible with the OLS test article are described. The AH-1G OLS flight test data was found to be well documented and provide a sound basis for evaluating currently existing analysis methods used for calculation of coupled rotor-fuselage vibrations.

Dompka, R. V.; Cronkhite, J. D.

1986-01-01

437

Ablation of wires in an inverse wire array z-pinch  

NASA Astrophysics Data System (ADS)

We describe experiments on the MAGPIE facility (1MA, 250ns) with inverse wire array z-pinches, in which the wires act as a return current cage placed around a central current conductor. In this configuration the plasma ablated from the wires is pushed by the JxB force in the radially outward direction and expands into the region free of the magnetic field. This allows quantitative characterisation of the plasma ablated from an individual wire using laser interferometry, X-ray radiography and XUV imaging. The inverse z-pinch configuration also allows to measure separately the contribution to the inductance coming from the ``private'' magnetic flux of the wires and thus to evaluate the size of the current-carrying region around the wire cores. Quantitative information obtained in these experiments will be compared with results of 3-D MHD computer simulations.

Lebedev, Sergey; Hall, G. N.; Bland, S. N.; Suzuki-Vidal, F. A.; Chittenden, J. P.; Jennings, C.; Harvey-Thompson, A.; Ning, Cheng; Palmer, J. B. A.

2007-11-01

438

MT1M and MT1G promoter methylation as biomarkers for hepatocellular carcinoma  

PubMed Central

AIM: To investigate the potential of promoter methylation of two tumor suppressor genes (TSGs) as biomarkers for hepatocellular carcinoma (HCC). METHODS: A total of 189 subjects were included in this retrospective cohort, which contained 121 HCC patients without any history of curative treatment, 37 patients with chronic hepatitis B (CHB), and 31 normal controls (NCs). DNA samples were extracted from 400 ?L of serum of each subject and then modified using bisulfite treatment. Methylation of the promoters of the TSGs (metallothionein 1M, MT1M; and metallothionein 1G, MT1G) was determined using methylation-specific polymerase chain reaction. The diagnostic value of combined MT1M and MT1G promoter methylation was evaluated using the area under the receiver operating characteristic curves. RESULTS: Our results indicated that the methylation status of serum MT1M (48.8%, 59/121) and MT1G (70.2%, 85/121) promoters in the HCC group was significantly higher than that in the CHB group (MT1M 5.4%, 2/37, P < 0.001; MT1G 16.2%, 6/37, P < 0.001) and NC group (MT1M 6.5%, 2/31, P < 0.001; MT1G 12.9%, 4/27, P < 0.001). Aberrant serum MT1M promoter methylation gave higher specificity to discriminate HCC from CHB (94.6%) and NCs (93.5%), whereas combined methylation of serum MT1M and MT1G promoters showed higher diagnostic sensitivity (90.9%), suggesting that they are potential markers for noninvasive detection of HCC. Furthermore, MT1M promoter methylation was positively correlated with tumor size (rs = 0.321, P < 0.001), and HCC patients with both MT1M and MT1G promoter methylation tended to show a higher incidence of vascular invasion or metastasis (P = 0.018). CONCLUSION: MT1M and MT1G promoter methylation may be used as serum biomarkers for noninvasive detection of HCC. PMID:24782625

Ji, Xiang-Fen; Fan, Yu-Chen; Gao, Shuai; Yang, Yang; Zhang, Jian-Jun; Wang, Kai

2014-01-01

439

Scattering by an Arbitrary Array of Parallel Wires  

Microsoft Academic Search

Equations are developed for the scattering pattern of an arbitrary array of parallel wires. The wires are assumed to be infinitely long, perfectly conducting, and very small in diameter in comparison with the wavelength. The incident wave is assumed to be TM with respect to the wire axis, but it may have normal or oblique incidence on the wires. The

J. H. Richmond

1965-01-01

440

An efficient curved-wire integral equation solution technique  

Microsoft Academic Search

Computation of the currents on curved-wires by integral equation methods is often inefficient when the structure is tortuous but the length of wire is not large relative to the wavelength at the frequency of operation. The number of terms needed in an accurate piecewise straight model of a highly curved-wire can be large, yet, if the total length of wire

Shawn D. Rogers; Chalmers M. Butler

2001-01-01

441

Optimal Design of Shape Memory Alloy Wire Bundle Actuators  

Microsoft Academic Search

This research studied the optimal design of Shape Memory Alloy (SMA) muscle wire bundle actuators. Current literature describes the use of multiple muscle wires placed in parallel to increase the lifting capabilities of an SMA actuator, which however, is limited to wires of like -diameter. A constrained optimization problem was formulated, with constraints on the maximum number of wires, voltage

Kathryn J. De Laurentis; Avi Fisch; Jason Nikitczuk; Constantinos Mavroidis

2002-01-01

442

Copper wire bonding challenges and solutions of small outline packages  

Microsoft Academic Search

Moving towards next level of major cost saving in small outline packages, conversion from gold wire to copper wire became necessary action. With normal production expectations of fast bonding and good quality performance on flimsy leadframe, copper wire challenges of small outline packages were incredible. Furthermore, situation became worse when new copper wire process was found requiring additional bonding time

Nicole Lin; C. E. Tan; Y. J. Pan

2010-01-01

443

A simplified post process for wire cut EDM  

Microsoft Academic Search

The paper deals with a technical realization to improve the Wire EDM accuracy while cutting at full speed on virtually any contour. The system which is readily available on commercial wire EDM machines is based on the on-line monitoring and control of the wire position by means of an optical sensor. The deviation of the wire position relative to the

Ivano Beltrami; Axel Bertholds; Dirk Dauw

1996-01-01

444

t matrix of metallic wire structures  

SciTech Connect

To study the electromagnetic resonance and scattering properties of complex structures of which metallic wire structures are constituents within multiple scattering theory, the t matrix of individual structures is needed. We have recently developed a rigorous and numerically efficient equivalent circuit theory in which retardation effects are taken into account for metallic wire structures. Here, we show how the t matrix can be calculated analytically within this theory. We illustrate our method with the example of split ring resonators. The density of states and cross sections for scattering and absorption are calculated, which are shown to be remarkably enhanced at resonant frequencies. The t matrix serves as the basic building block to evaluate the interaction of wire structures within the framework of multiple scattering theory. This will open the door to efficient design and optimization of assembly of wire structures.

Zhan, T. R., E-mail: phystrzhan@gmail.com; Chui, S. T., E-mail: chui@bartol.udel.edu [Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)

2014-04-14

445

Exploiting level sensitive latches in wire pipelining  

E-print Network

The present research presents procedures for exploitation of level sensitive latches in wire pipelining. The user gives a Steiner tree, having a signal source and set of destination or sinks, and the location in rectangular plane, capacitive load...

Seth, Vikram

2005-02-17

446

Wiring test program insulation material related properties  

NASA Technical Reports Server (NTRS)

This viewgraph presentation provides an overview of activities at DASA-RI concerning the testing of wires for manned spacecraft, including test facilities, arc-tracking tests, flammability tests, microgravity tests, and standardization, and outlines future activities.

Reher, Heinz-Josef

1995-01-01

447

Force-controlled lifting of molecular wires  

NASA Astrophysics Data System (ADS)

Lifting a single molecular wire off the surface with a combined frequency-modulated atomic force and tunneling microscope it is possible to monitor the evolution of both the wire configuration and the contacts simultaneously with the transport conductance experiment. In particular, critical points where individual bonds to the surface are broken and instabilities where the wire is prone to change its contact configuration can be identified in the force gradient and dissipation responses of the junction. This additional mechanical information can be used to unambiguously determine the conductance of a true molecular wire, that is, of a molecule that is contacted via a pointlike “crocodile clip” to each of the electrodes but is otherwise free.

Fournier, N.; Wagner, C.; Weiss, C.; Temirov, R.; Tautz, F. S.

2011-07-01

448

Evaluation of Wiring Constructions for Space Applications  

NASA Technical Reports Server (NTRS)

A NASA Office of Safety and Mission Assurance (OS&MA) program to develop lightweight, reliable, and safe wiring insulations for aerospace applications is being performed by the NASA Lewis Research Center (LeRC). As part of this effort, a new wiring construction utilizing high strength PTFE (poly tetrafluoroethylene) as the insulation has been tested and compared with the existing military standard polyimide-based MIL-W-81381 wire construction. Electrical properties which were investigated included ac corona inception and extinction voltages (sea level and 60,000 feet), time/current to smoke, and wire fusing time. The two constructions were also characterized in terms of their mechanical properties of flexural strength, abrasion resistance (23 C and 150 C), and dynamic cut-through (23 C and 200 C). The results obtained in this testing effort are presented and discussed in this paper.

Hammoud, Ahmad N.; Stavnes, Mark W.; Dickman, John E.; Burkhardt, Linda A.; Woodford, Lynn M.; Ide, James R.; Muegge, ED

1994-01-01

449

Superconducting wire for NMR-tomography  

SciTech Connect

The paper discusses the fabrication of Nb-Ti base superconducting wires having the superconductor packing factor of 15-20% and superconducting filaments 70-80 {mu}m dia. Three methods of precursor fabrication were tried. The NbTi-50 alloy base superconducting wire was fabricated to be used for the magnet system of a NMR-tomograph; the wire diameter is 0.85 mm; the packing factor is 16%; the maximum length of a single piece is 29 km{sub 2}. The critical current density is 6.1 {times} 10{sup 5} A/cm{sup 2} in the magnetic field of 1 T. The paper also presents the superconducting properties of similar wire on the NbTi-55 alloy base.

Filkin, V.Y.; Plashkin, E.I.; Salunin, N.I.; Morozova, T.A.; Zelenskiy, G.K.; Vlasova, L.V.; Drobyshev, V.A.; Zinovev, V.G.; Yakovlev, B.V. (All-Union Scientific and Research Inst. of Inorganic Materials, 123060 Moscow (SU))

1992-01-01

450

Improvements to Existing Jefferson Lab Wire Scanners  

SciTech Connect

This poster will detail the augmentation of selected existing CEBAF wire scanners with commercially available hardware, PMTs, and self created software in order to improve the scanners both in function and utility.

McCaughan, Michael D. [JLAB; Tiefenback, Michael G. [JLAB; Turner, Dennis L. [JLAB

2013-06-01

451

Printed wiring board system programmer's manual  

NASA Technical Reports Server (NTRS)

The printed wiring board system provides automated techniques for the design of printed circuit boards and hybrid circuit boards. The system consists of four programs: (1) the preprocessor program combines user supplied data and pre-defined library data to produce the detailed circuit description data; (2) the placement program assigns circuit components to specific areas of the board in a manner that optimizes the total interconnection length of the circuit; (3) the organizer program assigns pin interconnections to specific board levels and determines the optimal order in which the router program should attempt to layout the paths connecting the pins; and (4) the router program determines the wire paths which are to be used to connect each input pin pair on the circuit board. This document is intended to serve as a programmer's reference manual for the printed wiring board system. A detailed description of the internal logic and flow of the printed wiring board programs is included.

Brinkerhoff, C. D.

1973-01-01

452

Development of tunable terahertz wire lasers  

E-print Network

We report a novel tuning mechanism based on a “wire-laser” with subwavelength transverse dimensions(w??). By manipulating the waveguided mode propagating outside the cavity, frequency tuning of ?137GHz (3.6%) is demonstrated ...

Hu, Qing

453

An advanced arc track resistant airframe wire  

NASA Technical Reports Server (NTRS)

Tensolite, a custom cable manufacturer specializing in high temperature materials as the dielectric medium, develops an advance arc track resistant airframe wire called Tufflite 2000. Tufflite 2000 has the following advantages over the other traditional wires: lighter weight and smaller in diameter; excellent wet and dry arc track resistance; superior dynamic cut-through performance even at elevated temperatures; flight proven performance on Boeing 737 and 757 airplanes; and true 260 C performance by utilizing Nickel plated copper conductors. This paper reports the different tests performed on Tufflite 2000: accelerated aging, arc resistance (wet and dry), dynamic cut through, humidity resistance, wire-to-wire abrasion, flammability, smoke, weight, notch sensitivity, flexibility, and markability. It particularly focuses on the BSI (British Standards Institute) dry arc resistance test and BSI wet arc tracking.

Beatty, J.

1995-01-01

454

Fabrication of terahertz wire-grid polarizers.  

PubMed

Wire-grid polarizers for terahertz region were fabricated by manufacturing triangular grating using a ruling-based, ultraprecision diamond machining process and replicating the pattern into polymethylpentene (TPX) and cyklo-olefin copolymer (COC) sheets using hot embossing. On top of the imprinted structures, aluminum was evaporated in an oblique angle, forming an aluminum wire grid. The achieved extinction rate was over 150 for TPX polarizers and near 1000 for COC polarizers. PMID:23262530

Partanen, Anni; Väyrynen, Juha; Hassinen, Sami; Tuovinen, Hemmo; Mutanen, Jarkko; Itkonen, Tommi; Silfsten, Pertti; Pääkkönen, Pertti; Kuittinen, Markku; Mönkkönen, Kari; Venäläinen, Tapani

2012-12-10

455

Note: Improved wire-wound heater  

NASA Astrophysics Data System (ADS)

The authors have measured, at cryogenic temperature, the upper limit of the heat transfer in different configurations of a wire-wound heater. We found that the heat transferred has an upper limit of about 15 W/cm2 and is dependent on the diameter of the wire. In this paper, we present three ways of increasing the heat transferred by this type of heater and its application in different continuous flow cryostats.

Steinmann, Ricardo G.; Vitoux, Hugo

2015-01-01

456

Energetic additive manufacturing process with feed wire  

DOEpatents

A process for additive manufacture by energetic wire deposition is described. A source wire is fed into a energy beam generated melt-pool on a growth surface as the melt-pool moves over the growth surface. This process enables the rapid prototyping and manufacture of fully dense, near-net shape components, as well as cladding and welding processes. Alloys, graded materials, and other inhomogeneous materials can be grown using this process.

Harwell, Lane D. (Albuquerque, NM); Griffith, Michelle L. (Albuquerque, NM); Greene, Donald L. (Corrales, NM); Pressly, Gary A. (Sandia Park, NM)

2000-11-07

457

‘Chrysanthemum petal’ arrangements of silver nano wires  

NASA Astrophysics Data System (ADS)

Highly ordered ‘Chrysanthemum petal’ arrangements of silver nano wires were fabricated in a biodegradable polymer of polyvinyl alcohol using a simple one-step blending method without any template. The degree of the arrangement increased with the decreasing content of polyvinyl alcohol. The mechanism for the formation of these ‘Chrysanthemum petal’ arrangements was discussed specifically. These ‘Chrysanthemum petal’ arrangements will be helpful to increase the electrical conductivity of silver nano wires films.

Cui, Hui-Wang; Jiu, Jin-Ting; Sugahara, Tohru; Nagao, Shijo; Suganuma, Katsuaki; Uchida, Hiroshi

2014-12-01

458

TOWARDS DRIVE-BY-WIRE AUTOMOBILES  

Microsoft Academic Search

The development of automotive systems shows an increasing integration of electronic sen- sors, microcomputers and actuators for single components, engine, drive-chain, suspensions and brakes. After considering electronic driver assisting systems such as ABS, TCS, ASR, ESP, BA the developments towards drive-by-wire systems with and without mechanical or hydraulic backup are considered. Drive-by-wire systems consist of an operating unit (steering wheel,

Rolf Isermann

2000-01-01

459

A Magnetic Sensor with Amorphous Wire  

PubMed Central

Using a FeCoSiB amorphous wire and a coil wrapped around it, we have developed a sensitive magnetic sensor. When a 5 mm long amorphous wire with the diameter of 0.1 mm was used, the magnetic field noise spectrum of the sensor was about 30 pT/?Hz above 30 Hz. To show the sensitivity and the spatial resolution, the magnetic field of a thousand Japanese yen was scanned with the magnetic sensor. PMID:24940865

He, Dongfeng; Shiwa, Mitsuharu

2014-01-01

460

CIIA prevents SOD1(G93A)-induced cytotoxicity by blocking ASK1-mediated signaling  

PubMed Central

Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease with higher selectivity in degeneration of motor neurons. However, the molecular mechanism by which the ALS-linked mutants of human superoxide dismutase 1 (SOD1) gene induce neurotoxicity remains obscure yet. Here, we show that depletion of CIIA expression by RNA interference (RNAi) promoted cytotoxicity caused by ALS-linked G93A mutant of the SOD1 gene. The RNAi-mediated knockdown of CIIA also enhanced the SOD1(G93A)-induced interaction between ASK1 and TRAF2 as well as ASK1 activity. Furthermore, endogenous silencing of CIIA by RNAi augmented the effects of SOD1(G93A) on reduction of mitochondria membrane potential (??m), release of cytochrome c into the cytoplasm, and caspase activation. Together, our results suggest that CIIA negatively modulates ASK1-mediated cytotoxic signaling processes in a SOD1(G93A)-expressing cellular model of ALS. PMID:25018698

Lee, Jae Keun; Hwang, Sang Gil; Shin, Jin Hee; Shim, Jaekyung; Choi, Eui-Ju

2014-01-01

461

Si Wire-Array Solar Cells  

NASA Astrophysics Data System (ADS)

Micron-scale Si wire arrays are three-dimensional photovoltaic absorbers that enable orthogonalization of light absorption and carrier collection and hence allow for the utilization of relatively impure Si in efficient solar cell designs. The wire arrays are grown by a vapor-liquid-solid-catalyzed process on a crystalline (111) Si wafer lithographically patterned with an array of metal catalyst particles. Following growth, such arrays can be embedded in polymethyldisiloxane (PDMS) and then peeled from the template growth substrate. The result is an unusual photovoltaic material: a flexible, bendable, wafer-thickness crystalline Si absorber. In this paper I will describe: 1. the growth of high-quality Si wires with controllable doping and the evaluation of their photovoltaic energy-conversion performance using a test electrolyte that forms a rectifying conformal semiconductor-liquid contact 2. the observation of enhanced absorption in wire arrays exceeding the conventional light trapping limits for planar Si cells of equivalent material thickness and 3. single-wire and large-area solid-state Si wire-array solar cell results obtained to date with directions for future cell designs based on optical and device physics. In collaboration with Michael Kelzenberg, Morgan Putnam, Joshua Spurgeon, Daniel Turner-Evans, Emily Warren, Nathan Lewis, and Harry Atwater, California Institute of Technology.

Boettcher, Shannon

2010-03-01

462

Needleless electrospinning with twisted wire spinneret  

NASA Astrophysics Data System (ADS)

A needleless electrospinning setup named ‘Needleless Twisted Wire Electrospinning’ was developed. The polymer solution is electrospun from the surface of a twisted wire set to a high voltage and collected on a cylindrical collector around the wire. Multiple Taylor cones are simultaneously self-formed on the downward flowing solution. The system is robust and simple with no moving parts aside from the syringe pump used to transport the solution to the top of the wire. The structure and process parameters of the setup and the results on the preparation of polyvinyl pyrrolidone (PVP), hydroxyapatite (HA) and bioglass fibers with the setup are presented. PVP fiber sheets with areas of 40 × 120 cm2 and masses up to 1.15 g were prepared. High production rates of 5.23 g h?1 and 1.40 g h?1 were achieved for PVP and HA respectively. The major limiting factor of the setup is drying of the polymer solution on the wire during the electrospinning process which will eventually force to interrupt the process for cleaning of the wire. Possible solutions to this problem and other ways to develop the setup are discussed. The presented system provides a simple way to increase the production rate and area of fiber sheet as compared with the conventional needle electrospinning.

Holopainen, Jani; Penttinen, Toni; Santala, Eero; Ritala, Mikko

2015-01-01

463

Chemistry of radiation damage to wire chambers  

SciTech Connect

Proportional counters are used to study aspects of radiation damage to wire chambers (wire aging). Principles of low-pressure, rf plasma chemistry are used to predict the plasma chemistry in electron avalanches (1 atm, dc). (1) Aging is studied in CF{sub 4}/iC{sub 4}H{sub 10} gas mixtures. Wire deposits are analyzed by Auger electron spectroscopy. An apparent cathode aging process resulting in loss of gain rather than in a self-sustained current is observed in CF{sub 4}-rich gases. A four-part model considering plasma polymerization of the hydrocarbon, etching of wire deposits by CF{sub 4}, acceleration of deposition processes in strongly etching environments, and reactivity of the wire surface is developed to understand anode wire aging in CF{sub 4}/iC{sub 4}H{sub 10} gases. Practical guidelines suggested by the model are discussed. (2) Data are presented to suggest that trace amounts of Freons do not affect aging rates in either dimethyl ether or Ar/C{sub 2}H{sub 6}. Apparent loss of gain is explained by attachment of primary electrons to a continuously increasing concentration of Freon 11 (CCl{sub 3}F) in the counter gas. An increase in the concentration of Freon 11 in dimethyl ether is caused by a distillation process in the gas supply bottle and is a natural consequence of the unequal volatilities of the two compounds.

Wise, J.

1992-08-01

464

ULF-NMR system using HTS-SQUID and permanent magnet  

NASA Astrophysics Data System (ADS)

We have constructed an ultra-low field (ULF) nuclear magnetic resonance (NMR)/magnetic resonance imaging (MRI) system using an HTS-rf-SQUID and room-temperature electromagnets in a magnetically shielded room (MSR). In this study, in order to improve the signal to noise ratio (S/N) of the system, we introduced a permanent magnet instead of the electromagnet for pre-polarizing the sample to enhance the pre-polarizing field (Bp). The cylindrical permanent magnet of 270 mT was used to magnetize a water sample for several seconds outside the MSR and about 1.5 m away from the SQUID. We constructed an instrument to transfer the magnetized sample from the permanent magnet to under the SQUID in 0.5 s. Since the non-adiabatic condition cannot be kept in such sample transfer scheme, an AC pulse coil to apply an AC pulse field BAC to rotate the magnetization moments for ?/2 was introduced to measure a free induction decay (FID) signal from the sample. By this system, we obtained an NMR signal from the water sample of 10 ml while applying a static field of 45 ?T and ?/2 pulse after the transfer. The S/N of the NMR spectrum was about 100 by a single shot, which was 10 times larger than that obtained with the electromagnet of 32 mT. In addition, we demonstrated the measurements of the longitudinal relaxation time (T1) and the spin echo signal of the water sample by the system.

Fukumoto, Shohei; Tsunaki, Shingo; Chigasaki, Takumi; Hatsukade, Yoshimi; Tanaka, Saburo

2013-01-01

465

Modal parameters of space structures in 1 G and 0 G  

NASA Technical Reports Server (NTRS)

Analytic and experimental results are presented from a study of the changes in the modal parameters of space structural test articles from one- to zero-gravity. Deployable, erectable, and rotary modules was assembled to form three one- and two-dimensional structures, in which variations in bracing wire and rotary joint preload could be introduced. The structures were modeled as if hanging from a suspension system in one gravity, and unconstrained, as if free floating in zero-gravity. The analysis is compared with ground experimental measurements, which were made on a spring-wire suspension system with a nominal plunge frequency of one Hertz, and with measurements made on the Shuttle middeck. The degree of change in linear modal parameters as well as the change in nonlinear nature of the response is examined. Trends in modal parameters are presented as a function of force amplitude, joint preload, reassembly, shipset, suspension, and ambient gravity level.

Bicos, Andrew S.; Crawley, Edward F.; Barlow, Mark S.; Van Schoor, Marthinus C.; Masters, Brett

1993-01-01

466

Discovery of Small Molecule Kappa Opioid Receptor Agonist and Antagonist Chemotypes through a HTS and Hit Refinement Strategy  

PubMed Central

Herein we present the outcome of a high throughput screening (HTS) campaign-based strategy for the rapid identification and optimization of selective and general chemotypes for both kappa (?) opioid receptor (KOR) activation and inhibition. In this program, we have developed potent antagonists (IC50 < 120 nM) or agonists of high binding affinity (Ki < 3 nM). In contrast to many important KOR ligands, the compounds presented here are highly modular, readily synthesized, and, in most cases, achiral. The four new chemotypes hold promise for further development into chemical tools for studying the KOR or as potential therapeutic lead candidates. PMID:22737280

2012-01-01

467

Israel Journal of Entomology 1g79 Vol. XIII, pp. 1-11  

E-print Network

I Israel Journal of Entomology 1g79 Vol. XIII, pp. 1-11 OBSERVATIONS ON THE PHENOLOGY of Israel and Jordan, the moth being apparently endemic to the region. The biology and development time various constant temperatures as well as ambient conditIons In the Coastal plain of Israel. The adult

Mathis, Wayne N.

468

Origin of a1g and eg' orderings in NaxCoO2  

NASA Astrophysics Data System (ADS)

It has often been suggested that correlation effects suppress the small eg' Fermi-surface pockets of NaxCoO2 that are predicted by LDA, but absent in ARPES measurements. It appears that within the dynamical mean-field theory (DMFT) the ARPES results can be reproduced only if the on-site energy of the eg' complex is lower than that of the a1g complex at the one-electron level, prior to the addition of local correlation effects. Current estimates regarding the order of the two orbital complexes range from -200 to 315 meV in terms of the energy difference. In this work, we perform density-functional theory calculations of this one-electron splitting ?=?a1g-?eg' for the full two-layer compound, accounting for the effects of Na ordering, interplanar interactions and octahedral distortion. We find that ?a1g-?eg' is negative for all Na fillings and that this is primarily due to the strongly positive Coulomb field created by Na+ ions in the intercalant plane that disproportionately affects the extended a1g orbital. We discuss also the effects of octahedral compression and multiorbital filling on the value of ? as a function of Na content. Our results indicate that if the eg' pockets are indeed suppressed, that can only be due to nonlocal correlation effects beyond the standard DMFT.

Pillay, D.; Johannes, M. D.; Mazin, I. I.; Andersen, O. K.

2008-07-01

469

Influences of velocity gradient on hot-wire anemometry with an X-wire probe  

Microsoft Academic Search

The errors involved in the values obtained by an X-wire probe used for measuring a steady turbulent flow with velocity gradients are analyzed. Based on the analysis, a new measurement method is proposed which eliminates the errors caused by velocity gradients. In accordance with the method, two X-wire probes, one of which is a mirror image of the other, are

Masafumi Hirota; Hideomi Fujita; Hajime Yokosawa

1988-01-01

470

Studies of friction and wear characteristics of various wires for wire-brush skids  

NASA Technical Reports Server (NTRS)

The friction and wear characteristics of 22 types and sizes of wires for potential use in wire-brush skids were studied. These characteristics were determined by placing brushes made from candidate wires on a belt sander whose moving belt simulated landing roll-out distance. At the same time, the drag force and wear behavior were monitored. Data were obtained over distances up to 3048 m (10,000 ft) at preselected bearing pressures of 172 to 1034 kPa (25 to 150 psi). In general, the friction coefficient developed by the candidate wires was found to be independent of bearing pressure and ranged between 0.4 and 0.6 under the test conditions of this investigation. The friction coefficient was not degraded when the surface was wetted and appears to be independent of wire diameter except perhaps when wire size is relatively large compared with the surface asperities. Generally, the high friction demonstrated by the soft materials was accompanied by high wear rates; conversely, the hard materials provided greater wear resistance but offered lower friction. For all test wires, the wear was shown to increase with increasing bearing pressure, in general, for the same bearing pressure, wear increased with increasing wire diameter and decreased when the surface was wetted.

Dreher, R. C.

1977-01-01

471

Modelling and analysis of the wire-tool vibration in wire-cut EDM  

Microsoft Academic Search

Although wire-cut electrical discharge machining (WEDM) has revolutionised the present day metal cutting, die making and press tool manufacturing industries, further improvements are still required to meet the increasing demand of product precision and accuracy in those sectors of manufacturing. The machining performance in this regard is greatly influenced by the wire-tool vibration occurring during machining. This paper briefs an

A. B. Puri; B. Bhattacharyya

2003-01-01

472

STRS SpaceWire FPGA Module  

NASA Technical Reports Server (NTRS)

An FPGA module leverages the previous work from Goddard Space Flight Center (GSFC) relating to NASA s Space Telecommunications Radio System (STRS) project. The STRS SpaceWire FPGA Module is written in the Verilog Register Transfer Level (RTL) language, and it encapsulates an unmodified GSFC core (which is written in VHDL). The module has the necessary inputs/outputs (I/Os) and parameters to integrate seamlessly with the SPARC I/O FPGA Interface module (also developed for the STRS operating environment, OE). Software running on the SPARC processor can access the configuration and status registers within the SpaceWire module. This allows software to control and monitor the SpaceWire functions, but it is also used to give software direct access to what is transmitted and received through the link. SpaceWire data characters can be sent/received through the software interface, as well as through the dedicated interface on the GSFC core. Similarly, SpaceWire time codes can be sent/received through the software interface or through a dedicated interface on the core. This innovation is designed for plug-and-play integration in the STRS OE. The SpaceWire module simplifies the interfaces to the GSFC core, and synchronizes all I/O to a single clock. An interrupt output (with optional masking) identifies time-sensitive events within the module. Test modes were added to allow internal loopback of the SpaceWire link and internal loopback of the client-side data interface.

Lux, James P.; Taylor, Gregory H.; Lang, Minh; Stern, Ryan A.

2011-01-01

473

Selected developments in laser wire stripping. [cutting insulation from aerospace-type wires and cables  

NASA Technical Reports Server (NTRS)

The operation of mechanical and thermal strippers and the early development of laser wire strippers are reviewed. NASA sponsored development of laser wire stripping for space shuttle includes bench-type strippers as well as an advanced portable hand-held stripper which incorporates a miniaturized carbon dioxide laser and a rotating optics unit with a gas-jet assist and debris exhaust. Drives and controls girdle the wire and slit the remaining slug without manual assistance. This unit can strip wire sizes 26 through 12 gage. A larger-capacity hand-held unit for wire sizes through 1/0 gage was built using a neodynium-doped yttrium aluminum garnet (Nd:YAG) laser. The hand-held units have a flexible umbilical cable to an accompanying cart that carries the power supply, gas supply, cooling unit, and the controls.

1977-01-01

474

Investigation of factors affecting the heater wire method of calibrating fine wire thermocouples  

NASA Technical Reports Server (NTRS)

An analytical investigation was made of a transient method of calibrating fine wire thermocouples. The system consisted of a 10 mil diameter standard thermocouple (Pt, Pt-13% Rh) and an 0.8 mil diameter chromel-alumel thermocouple attached to a 20 mil diameter electrically heated platinum wire. The calibration procedure consisted of electrically heating the wire to approximately 2500 F within about a seven-second period in an environment approximating atmospheric conditions at 120,000 feet. Rapid periodic readout of the standard and fine wire thermocouple signals permitted a comparison of the two temperature indications. An analysis was performed which indicated that the temperature distortion at the heater wire produced by the thermocouple junctions appears to be of negligible magnitude. Consequently, the calibration technique appears to be basically sound, although several practical changes which appear desirable are presented and discussed. Additional investigation is warranted to evaluate radiation effects and transient response characteristics.

Keshock, E. G.

1972-01-01

475

[A study of mechanical properties of orthodontic wires in tension].  

PubMed

Orthodontic forces are applied to the teeth basically by means of different types of orthodontic wires. Knowledge of the mechanical properties of such wires are very helpful to the clinician in design and application of optimal force systems during orthodontic treatment. The basic mechanical properties were studied for 17 types of orthodontic wires (all rectangular and of the same size), in tension. Modulus of elasticity (E), yield strength (YS) and maximum elastic strain (Springback) (YS/E) were calculated for each type of wires. Stainless steel wires have demonstrated higher modulus of elasticity (and yield strength) in comparison with wires of nickel-titanium and beta titanium alloys. B-titanium wires showed higher modulus of elasticity than nickel-titanium ones. In addition stainless steel wires were found to have higher values for springback than cobalt-chromium ones and lower values (for the same variable) than nickel-titanium and B-titanium wires. PMID:2129597

Konstantellos, B; Lagoudakis, M; Toutountzakis, N

1990-12-01

476

Chinese NiTi wire--a new orthodontic alloy.  

PubMed

Chinese NiTi wire was studied by means of a bending test to determine wire stiffness, springback, and maximum bending moments. Chinese NiTi wire has an unusual deactivation curve (unlike steel and nitinol wires) in which relatively constant forces are produced over a long range of action. The characteristic flexural stiffness of NiTi wire is determined by the amount of activation. At large activations NiTi wires has a stiffness of only 7% that of a comparable stainless steel wire, and at small activations 28% of steel wire. For the same activation at large deflections, the forces produced are 36% that of a comparable nitinol wire. Chinese NiTi wire demonstrates phenomenal springback. It can be deflected 1.6 times as far as nitinol wire or 4.4 times as far as stainless steel wire without appreciable permanent deformation. NiTi wire is highly useful in clinical situations that require a low-stiffness wire with an extremely large springback. PMID:3890554

Burstone, C J; Qin, B; Morton, J Y

1985-06-01

477

Integrated Electrical Wire Insulation Repair System  

NASA Technical Reports Server (NTRS)

An integrated system tool will allow a technician to easily and quickly repair damaged high-performance electrical wire insulation in the field. Low-melt polyimides have been developed that can be processed into thin films that work well in the repair of damaged polyimide or fluoropolymer insulated electrical wiring. Such thin films can be used in wire insulation repairs by affixing a film of this low-melt polyimide to the damaged wire, and heating the film to effect melting, flow, and cure of the film. The resulting repair is robust, lightweight, and small in volume. The heating of this repair film is accomplished with the use of a common electrical soldering tool that has been modified with a special head or tip that can accommodate the size of wire being repaired. This repair method can furthermore be simplified for the repair technician by providing replaceable or disposable soldering tool heads that have repair film already "loaded" and ready for use. The soldering tool heating device can also be equipped with a battery power supply that will allow its use in areas where plug-in current is not available

Williams, Martha; Jolley, Scott; Gibson, Tracy; Parks, Steven

2013-01-01

478

Towards nonlinear photonic wires in lithium niobate  

NASA Astrophysics Data System (ADS)

The development of wafer-scale (3'' diameter) smart-cut lithium niobate (LN) single-crystal films of sub-micrometer thickness is reported. Z-cut LN wafers, implanted by high energy He-ions, are crystal-bonded to a SiO2 layer on another Z-cut LN handle sample. The bonded pair of samples splits along the He-implanted layer by appropriate annealing. As this fabrication method is similar to the process widely used for silicon-on-insulator (SOI) fabrication, the resulting material is called LNOI. Two different routes to develop periodically poled LNOI photonic wires are discussed. The first one starts with poling of planar LNOI samples; the photonic wires are fabricated afterwards by ICP-etching. The second one starts with the fabrication of LNOI photonic wires; they are "locally" poled afterwards. As both approaches were not yet successful, a PPLN-substrate was ion beam sliced to generate a planar periodically poled LNOI sample directly. Using planar LNOI samples as starting material, high-quality photonic wires have been developed. The smallest structure has a cross-section of ~ 1 x 0.7 ?m2 only. Its optical properties with mode distributions, waveguide propagation losses, and group index were investigated. Moreover, the first periodically poled LNOI photonic wires were successfully fabricated, but not yet investigated optically. They are of great potential for second order nonlinear integrated optics.

Hu, Hui; Gui, Li; Ricken, Raimund; Sohler, Wolfgang

2010-02-01

479