12 tesla test coil. Annual progress report

International Nuclear Information System (INIS)

1979-01-01

The Plasma Fusion Center at MIT has been charged with responsibility for the design, development, fabrication and test operation of a Niobium-3-Tin Superconducting Test Coil. Research is described on DOE's 12 tesla coil demonstration program in which several one-meter diameter superconducting test coils will be inserted and tested in DOE's High Field Test Facility at the Lawrence Livermore Laboratories. The work was initiated at the start of FY 79. FY 79 saw the completion of our Preliminary Design and the initiation of three (3) subcontracts: (1) Westinghouse review of the Preliminary Design, (II) Supercon, Inc. development of a tubular copper matrix, Nb 3 Sn Superconductor and (III) Airco optimization of the LCP-W Nb 3 Sn superconductor for 12T service. In addition, Airco was charged with the production of a 1000 foot length of model 15,000A conductor. Coil winding exercises were initiated at the Everson Electric Company

Demonstration poloidal coil test facility

International Nuclear Information System (INIS)

Sato, Masahiko; Kawano, Katumi; Tada, Eisuke

1989-01-01

A new compact cryogenic cold compressor was developed by Japan Atomic Energy Research Institute (JAERI) in collaboration with Isikawajima-Harima Heavy Industries Co., Ltd. (IHI) in order to produce the supercritical helium below 4.2 K for Demonstration Poloidal Coils (DPC) which are forced-flow cooled type superconducting pulse coils. This compressor is one of key components for DPC test facility. The cold compressor reduces pressure in liquid helium bath, which contains liquid helium of around 3,000 l, down to 0.5 atm efficiently. Consequently, supercritical helium down to 3.5 K is produced and supplied to the DPC coils. A centrifugal compressor with dynamic gas bearing is selected as a compressor mechanism to realize high adiabatic efficiency and large flow rate. In this performance tests, the compressor was operated for 220 h at saturated condition from 0.5 to 1.0 atm without any failure. High adiabatic efficiency (more than 60 %) is achieved with wide flow range (25-65 g/s) and the design value is fully satisfied. The compressor can rotate up to 80,000 rpm at maximum then the coil supply temperature of supercritical helium is 3.5 K. (author)

Electromagnetic results of the Japanese LCT coil's domestic test

International Nuclear Information System (INIS)

Nishi, Masataka; Okuno, Kiyoshi; Takahashi, Yoshikazu; Tsuji, Hiroshi; Ando, Toshinari; Shimamoto, Susumu

1984-01-01

The domestic test of the Japanese LCT coil was carried out in 1982. During this test, the coil was charged up to the single coil's 100% state (10.22kA, 6.4T, 106MJ) four times and experienced no quenche. at the 100% charging state, coil stability was tested by using heaters installed in the conductor. A half turn length normal zone (about 5 m) generated by heaters was spontenously disappeared in 2 second. This normalized zone included the highest magnetic field position. The transport current which gives the stable limit is extraporated to be about 12.5kA at 8T by this test result. The dump test was carried out also from the 100% charging state. At that time, about 90% of the coil's stored energy was extracted by the dump resistor and the coil was not damaged. (author)

The IEA large coil task test results in IFSMTF

International Nuclear Information System (INIS)

Lubell, M.S.; Clinard, J.A.; Dresner, L.

1987-01-01

The Large Coil Task (LCT) is an international collaboration of the United States, EURATOM, Japan, and Switzerland to develop large superconducting magnets for fusion reactors. The testing phase of LCT was completed on September 3, 1987. All six coils exceeded the design goals, both as single coils and in six-coil toroidal tests. In addition, a symmetric torus test was performed in which a maximum field of 9 T was reached in all coils simultaneously. These are by far the largest magnets (either in size, weight, or stored energy) ever to achieve such a field. 6 refs., 6 figs., 3 tabs

Neutron multiwave interference with many resonance coils: a test experiment

Energy Technology Data Exchange (ETDEWEB)

Chetverikov, Yu.O.; Axelrod, L.A.; Syromyatnikov, A.V.; Kraan, W.H.; Rekveldt, M.Th.; Grigoriev, S.V

2004-07-15

A test experiment on neutron multiwave interference based on Ramsey's resonance method of 'separated oscillating fields' has been performed. A neutron passes through N successive resonant coils (h{omega}{sub 0}=2{mu}{sub n}B{sub 0}), which flip the neutron spin with a probability {rho} smaller than 1. These coils are separated by path lengths L, over which a homogeneous field B{sub 1} is present. Since the spin-flip probability {rho} is smaller than 1, the number of waves for a neutron is doubled after each flipper, so as to produce 2{sup N} neutron waves at the end of the setup. The phase difference between any pair of waves is a multiple of a 'phase quantum' determined by the line integral of the field difference B{sub 1}-B{sub 0} over the length L. Highly regular patterns of the quantum mechanical probability R in (B{sub 1},{rho})--space appear owing to pairwise interference between individual waves.

Test of a model coil of TORE SUPRA

International Nuclear Information System (INIS)

Aymar, R.; Claudet, G.; Disdier, F.; Hamelin, J.; Libeyre, P.; Mayaux, C.; Meuris, C.; Parain, J.; Torossian, A.

1980-10-01

Inside the qualifying test programme, supporting the 'Tore Supra' Tokamak design, a reduced scale model of coil was fabricated by an industrial firm and fully tested. This model coil is provided with the same features as those retained for the complete magnet and is built according to the same design; in particular the Nb-Ti mixed matrix monolithic conductor is cooled by a pressurized superfluid helium bath, supplied from a model of the envisaged complete cryogenic system. Three main objectives have been assigned to this test: operation of the cryogenic system, stability of the superconductor winding under high mechanical stresses, mainly shear, and simulation of coil quench conditions. For this purpose, the model coil (outside bore 0.8 m) is located inside a 4 T magnet, an hydraulic jack applies a 1 MN force along a coil diameter. Operation of the model coil has been found highly stable, under the conditions of applied field and forces, a coil transition can be induced by an electrical heater only when the superfluid bath temperature is close to Tlambda. The 1.8 K cryogenic system provides a useful calorimetric measure of total losses induced inside the winding; its operation has been quite simple and reliable, permitting a sure extrapolation to a much larger size

NET model coil test possibilities in the TOSKA TWIN configuration

International Nuclear Information System (INIS)

Gruenhagen, A.; Heller, R.; Herz, W.; Hofmann, A.; Jentzsch, K.; Kapulla, H.; Kneifel, B.; Komarek, P.; Lehmann, W.; Maurer, W.; Ulbricht, A.; Vogt, A.; Zahn, G.

1989-07-01

This report continues an earlier one on the possibilities of NET model coil testing in the TOSKA Upgrade facility at KfK. The investigation of a 'Cluster Test Facility' and a 'Solenoid Test Facility' is followed by the investigation of two further test arrangements. They are called 'Twin Configurations'. One common feature of both arrangements is that the EURATOM-LCT-coil delivers a background magnetic field. This coil should be operated at a temperature of 1.8 K and an enhanced current up to 20 kA compared to the LCT test where 3.5 K and up to 16 kA were the operating conditions. In one configuration the NET model test coil is adjacent to the LCT coil (ATC = Adjacent Twin Configuration), in the other one the NET model coil is inserted into the bore of LCT coil (ITC = Inserted Twin Configuration) either upright or with a 60 0 C slope. The configurations are investigated with respect to their electromagnetic mechanical and thermo-hydraulic properties. The requirements for the necessary mechanical support structure of the LCT coil were computed. Installation and cooling of the whole system were discussed. The time schedule and the costs for the test facility modification were estimated. Advantages and disadvantages for the configurations were discussed with respect to feasibility of the test arrangement and operation. (orig.) [de

Qualifying tests for TRIAM-1M superconducting toroidal magnetic field coil

Energy Technology Data Exchange (ETDEWEB)

Nakanura, Yukio; Hiraki, Naoji; Nakamura, Kazuo; Tanaka, Masayoshi; Nagao, Akihiro; Kawasaki, Shoji; Itoh, Satoshi

1984-09-01

In the strong toroidal magnetic field experimental facility ''TRIAM-1M'' currently under construction, construction of the superconducting toroidal magnetic field coil and the following qualifying tests conducted on the full-scale superconducting toroidal magnetic field coil actually fabricated are described: (1) coil excitation test, (2) superconducting stability test, (3) external magnetic field application test, and (4) high-speed excitation test. On the basis of these test results, stability was evaluated of the superconducting coil being operated in the tokamak device. In normal tokamak operation, there occurs no normal conduction transition. At the time of plasma disruption, though this transition takes place in part of the coil, the superconducting state is immediately restored. By its electromagnetic force analysis, the superconducting coil is also stable in structure.

Background field coils for the High Field Test Facility

International Nuclear Information System (INIS)

Zbasnik, J.P.; Cornish, D.N.; Scanlan, R.M.; Jewell, A.M.; Leber, R.L.; Rosdahl, A.R.; Chaplin, M.R.

1980-01-01

The High Field Test Facility (HFTF), presently under construction at LLNL, is a set of superconducting coils that will be used to test 1-m-o.d. coils of prototype conductors for fusion magnets in fields up to 12 T. The facility consists of two concentric sets of coils; the outer set is a stack of Nb-Ti solenoids, and the inner set is a pair of solenoids made of cryogenically-stabilized, multifilamentary Nb 3 Sn superconductor, developed for use in mirror-fusion magnets. The HFTF system is designed to be parted along the midplane to allow high-field conductors, under development for Tokamak fusion machines, to be inserted and tested. The background field coils were wound pancake-fashion, with cold-welded joints at both the inner and outer diameters. Turn-to-turn insulation was fabricated at LLNL from epoxy-fiberglass strip. The coils were assembled and tested in our 2-m-diam cryostat to verify their operation

Design of superconducting toroidal magnet coils and testing facility in the USA

International Nuclear Information System (INIS)

Luton, J.N.; Haubenreich, P.N.; Thompson, P.B.

1977-01-01

In the U.S. Large Coil Program, three industrial teams are presently designing test coils to general specifications prepared by the Oak Ridge National Laboratory with guidance from USERDA. Each test coil is approximately half the bore size of reactor coils, being oval or D-shaped, with a bore of 2.5 x 3.5 m. The dimensions and operating requirements of the coils are identical for all test coils. The coils are designed to produce a peak field of at least 8 tesla at the winding of a selected coil operated at its design current. This condition is met when the selected coil is operated in a compact toroidal array of 6 coils, with the other five coils being operated at 0.8 of their design current. The six coils are of three different designs. Both pool boiling and forced flow designs are included. The coils are housed in a single large vacuum chamber for economy and testing convenience. Auxiliary coils provide a pulse field over the test coil winding volume. This auxiliary system is designed to produce a pulse field which rises to a peak of 0.14 T in 1 sec. With the exception of material damage due to neutron irradiation, all reactor requirements and environments will be either duplicated, approximated, or simulated. The test facility is being designed to accept coils producing up to 12 tesla in later phases of the program

Test results of the SMES model coil. Pulse performance

International Nuclear Information System (INIS)

Hamajima, Takataro; Shimada, Mamoru; Ono, Michitaka

1998-01-01

A model coil for superconducting magnetic energy storage (SMES model coil) has been developed to establish the component technologies needed for a small-scale 100 kWh SMES device. The SMES model coil was fabricated, and then performance tests were carried out in 1996. The coil was successfully charged up to around 30 kA and down to zero at the same ramp rate of magnetic field experienced in a 100 kWh SMES device. AC loss in the coil was measured by an enthalpy method as parameters of ramp rate and flat top current. The results were evaluated by an analysis and compared with short-sample test results. The measured hysteresis loss is in good agreement with that estimated from the short-sample results. It was found that the coupling loss of the coil consists of two major coupling time constants. One is a short time constant of about 200 ms, which is in agreement with the test results of a short real conductor. The other is a long time constant of about 30 s, which could not be expected from the short sample test results. (author)

Test results of Nb3Sn ribbons for the Princeton D coil test program

International Nuclear Information System (INIS)

Kaugerts, J.; File, J.; Willard, J.W.

1974-10-01

A previously described D coil test program was modified. Details of a smaller Nb 3 Sn D coil test program are described. Cusp coil tests were made with several Nb 3 Sn composite ribbons. Measurements of both the quench and recovery currents as a function of magnetic field component perpendicular to the wide edge of the ribbon are presented. (auth)

Development and testing of the cooling coil cleaning end effector

International Nuclear Information System (INIS)

Johnson, K.I.; Mullen, O.D.; Powell, M.R.; Daly, D.S.; Engel, D.W.

1997-01-01

The Retrieval Process Development and Enhancement (KPD ampersand E) program has developed and tested an end effector to support the waste retrieval mission at the Idaho National Engineering and Environmental Laboratory (INEEL). The end effector was developed specifically to remove a sticky waste material from the cooling coils in the High Level Liquid Waste (HLLW) tank, and to vacuum up a sediment layer that has settled beneath the cooling coils. An extensive testing program was conducted in the hydraulic test bed (HTB) at the Pacific Northwest National Laboratory (PNNL) to evaluate the performance of the end effector under simulated in-tank conditions. A mock up of the cooling coils was installed in the test bed tank, and simulated waste materials were included to represent the sticky waste on the tubes and the particulate waste settled beneath them. The testing program focused on assessing long-duration mining strategies for cleaning the cooling coils and removing the particulate waste forms. The report describes the results of the end effector testing program at PNNL. Section 2 describes the physical characteristics of the HLLW tanks, including the layout of the cooling coils, and it also describes what is known of the waste forms in the tanks. Section 3 describes the cleaning and retrieval strategy that was used in developing the end effector design. Section 4 describes the cooling coil mockup in the hydraulic test bed. Section 5 discusses the rationale used in selecting the simulants for the tarry waste and particulate waste forms. Section 6 describes the tests that were performed to evaluate cleaning of the cooling coils and retrieval of the particulate simulant. Section 7 summarizes the cleaning and retrieval tests, assesses the relative importance of cleaning the cooling coils and retrieving the particulate waste, and suggests modifications that would simplify the end effector design

Stability tests of the Westinghouse coil in the International Fusion Superconducting Magnet Test Facility

International Nuclear Information System (INIS)

Dresner, L.; Fehling, D.T.; Lubell, M.S.; Lue, J.W.; Luton, J.N.; McManamy, T.J.; Shen, S.S.; Wilson, C.T.

1987-09-01

The Westinghouse coil is one of three forced-flow coils in the six-coil toroidal array of the International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory. It is wound with an 18-kA, Nb 3 Sn/Cu, cable-in-conduit superconductor structurally supported by aluminum plates and cooled by 4-K, 15-atm supercritical helium. The coil is instrumented to permit measurement of helium temperature, pressure, and flow rate; structure temperature and strain; field; and normal zone voltage. A resistive heater has been installed to simulate nuclear heating, and inductive heaters have been installed to facilitate stability testing. The coil has been tested both individually and in the six-coil array. The tests covered charging to full design current and field, measuring the current-sharing threshold temperature using the resistive heaters, and measuring the stability margin using the pulsed inductive heaters. At least one section of the conductor exhibits a very broad resistive transition (resistive transition index = 4). The broad transition, though causing the appearance of voltage at relatively low temperatures, does not compromise the stability margin of the coil, which was greater than 1.1 J/cm 3 of strands. In another, nonresistive location, the stability margin was between 1.7 and 1.9 J/cm 3 of strands. The coil is completely stable in operation at 100% design current in both the single- and six-coil modes

Performance verification tests of JT-60SA CS model coil

Energy Technology Data Exchange (ETDEWEB)

Obana, Tetsuhiro, E-mail: obana.tetsuhiro@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Murakami, Haruyuki [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Takahata, Kazuya; Hamaguchi, Shinji; Chikaraishi, Hirotaka; Mito, Toshiyuki; Imagawa, Shinsaku [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kizu, Kaname; Natsume, Kyohei; Yoshida, Kiyoshi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

2015-11-15

Highlights: • The performance of the JT-60SA CS model coil was verified. • The CS model coil comprised a quad-pancake wound with a Nb{sub 3}Sn CIC conductor. • The CS model coil met the design requirements. - Abstract: As a final check of the coil manufacturing method of the JT-60 Super Advanced (JT-60SA) central solenoid (CS), we verified the performance of a CS model coil. The model coil comprised a quad-pancake wound with a Nb{sub 3}Sn cable-in-conduit conductor. Measurements of the critical current, joint resistance, pressure drop, and magnetic field were conducted in the verification tests. In the critical-current measurement, the critical current of the model coil coincided with the estimation derived from a strain of −0.62% for the Nb{sub 3}Sn strands. As a result, critical-current degradation caused by the coil manufacturing process was not observed. The results of the performance verification tests indicate that the model coil met the design requirements. Consequently, the manufacturing process of the JT-60SA CS was established.

First ATLAS Barrel Toroid Coil Passes Test

CERN Multimedia

2004-01-01

First they secured anything magnetic: metal tools, nuts and bolts, tables. Then they cleared the magnet assembly building, as big as an airplane hangar, and locked it tight. Before turning on the magnet for its maiden test, they waited till the dead of night so no one else would be around.

Manufacture and mechanical test of a TORE SUPRA model coil

International Nuclear Information System (INIS)

Aymar, R.; Claudet, G.; Disdier, F.; Hamelin, J.; Libeyre, P.; Mayaux, G.; Meuris, C.; Parain, J.; Torossian, A.

1980-09-01

Inside the qualifying test programme, supporting the Tore Supra Design, a reduced scale model of a Bsub(T) coil was fabricated by a large industrial firm. This model coil is provided with the same features as those retained for the complete magnet. Tests of this model coil have been carried out in such a way that most of stresses which will arise in Tore Supra windings are simulated; simultaneously its cryogenic supply is fully representative of the system retained for the complete machine. Operation of the model coil has been found highly stable; under the conditions of applied field and forces a coil transition could be triggered, by an electrical heater located inside the coil, only when the temperature of the superfluid helium bath was close to Tsub(lambda). Thus, design and manufacturing techniques have been qualified satisfactorily to proceed to the next step: fabrication of the superconducting Bsub(T) coils of Tore Supra

Status report on the 12T split coil test facility SULTAN

International Nuclear Information System (INIS)

Blau, B.; Aebli, E.; Jakob, B.; Pasztor, G.; Vecsey, G.; della Corte, A.; Pasotti, G.; Sacchetti, N.; Spadoni, M.

1992-01-01

The third phase of upgrading of the superconductor test facility SULTAN into a split coil system (SULTAN III) is in progress. SULTAN III a join project of ENEA (Italy) and PSI (Switzerland) consists of two coil packages, each containing three concentrically mounted superconducting solenoids. Together they will produce a field of nearly 12T between the two coil packages, inside a solenoid bore of 58 cm. The outermost 6T coils have NbTi conductors, whereas the inner 9T and 12T coils are made of A-15 cables. All Nb 3 Sn coils are manufactured by the react-and-wind technique. The split coil arrangement, in connection with a sophisticated sample insert containing a 50 kA superconducting transformer, will allow testing of short samples of high current carrying superconductors, e.g. for fusion applications. The sample insert was designed to allow changing the samples within a few hours without warming up the whole magnet system. This paper deals with the present status and potential of the Split Coil Test Facility SULTAN III

Testing of the European LCT coil in the TOSKA facility

International Nuclear Information System (INIS)

Herz, W.; Katheder, H.; Krauth, H.

1985-01-01

The EURATOM-LCT coil was tested as a single coil in TOSKA. Load cells were mounted in the support structure to monitor forces between coil and vacuum vessel during cooldown and coil charging. Disturbances of components by magnetic fringing fields were carefully considered. To investigate the mechanical behaviour and compare it with FEM-calculations the coil was equipped with strain gauge rosettes and displacement transducers. Van Mises stresses in the coil case are in agreement with calculations. As known from special investigations during coil manufacturing the average radial Young modulus varies along the periphery caused by the different curvatures. This leads to differences with FEM-calculation (larger gaps between winding and coil case) assuming a larger constant Young modulus performed at the beginning of the project

Preliminary results of the US pool-boiling coils from the IFSMTF full-array tests

International Nuclear Information System (INIS)

Lue, J.W.; Dresner, L.; Lubell, M.S.; Luton, J.N.; McManamy, T.J.; Shen, S.S.

1986-01-01

The Large Coil Task to develop superconducting magnets for fusion reactors, is now in the midst of full-array tests in the International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory. Included in the test array are two pool-boiling coils designed and fabricated by US manufacturers, General Dynamics/Convair Division and General Electric/Union Carbide Corporation. So far, both coils have been energized to full design currents in the single-coil tests, and the General Dynamics coil has reached the design point in the first Standard-I full-array test. Both coils performed well in the charging experiments. Extensive heating tests and the heavy instrumentation of these coils have, however, revealed some generic limitations of large pool-boiling superconducting coils. Details of these results and their analyses are reported

Development of Ground Coils with Low Eddy Current Loss by Applying the Compression Molding Method after the Coil Winding

Science.gov (United States)

Suzuki, Masao; Aiba, Masayuki; Takahashi, Noriyuki; Ota, Satoru; Okada, Shigenori

In a magnetically levitated transportation (MAGLEV) system, a huge number of ground coils will be required because they must be laid for the whole line. Therefore, stable performance and reduced cost are essential requirements for the ground coil development. On the other hand, because the magnetic field changes when the superconducting magnet passes by, an eddy current will be generated in the conductor of the ground coil and will result in energy loss. The loss not only increases the magnetic resistance for the train running but also brings an increase in the ground coil temperature. Therefore, the reduction of the eddy current loss is extremely important. This study examined ground coils in which both the eddy current loss and temperature increase were small. Furthermore, quantitative comparison for the eddy current loss of various magnet wire samples was performed by bench test. On the basis of the comparison, a round twisted wire having low eddy current loss was selected as an effective ground coil material. In addition, the ground coils were manufactured on trial. A favorable outlook to improve the size accuracy of the winding coil and uneven thickness of molded resin was obtained without reducing the insulation strength between the coil layers by applying a compression molding after winding.

Test results for a Bi-2223 HTS racetrack coil for generator applications

International Nuclear Information System (INIS)

Salasoo, L.; Herd, K.G.; Laskaris, E.T.; Hart, H.R. Jr.; Chari, M.V.K.

1996-01-01

Testing, results and analysis of a Bi-2223 model superconducting generator coil produced under the DOE Superconductivity Partnership Initiative are presented. The test arrangement enables coil energization with dc and transient currents over a range of operating temperatures to explore coil performance under conditions analogous to those that would be experienced by a superconducting generator field coil. Analytical calculations of coil ac and ohmic losses and temperature rise compare well with experimental measurements. Good performance is predicted for a typical 3-phase fault condition. Coil steady state and transient performance can be predicted with confidence for full scale superconductor application

Thermal results of the Japanese LCT coil's domestic test

International Nuclear Information System (INIS)

Tada, Eisuke; Hiyama, Tadao; Kato, Takashi; Takahashi, Osamu; Shimamoto, Susumu

1984-01-01

This paper describes thermal results obtained in the domestic test of the Japanese LCT coil which was constructed at the Japan Atomic Energy Research Institute (JAERI) in order to develop large superconducting coils for fusion in international collaboration proposed by the IEA. The domestic test was carried out from May 13 to June 17 in 1982 by using the test facility named as SETF (Superconducting Engineering Test Facility) which was composed of a 350-l/h helium cryogenic system, a vacuum system, a 30 KA-DC power supply and protection system, and a PDP-11/70 computer system. The cool-down characteristics, heat load, fast discharge characteristics, stability, and warm-up characteristics of the LCT coil were successfully measured in the test. The details of thermal test results acquired in the cool-down, heat load measurement, fast discharge, and warm-up, and the comparison between measurements and calculations are described in this paper. (author)

Active Protection of an MgB2 Test Coil

Science.gov (United States)

Park, Dong Keun; Hahn, Seungyong; Bascuñán, Juan; Iwasa, Yukikazu

2011-01-01

This paper presents results of a study, experimental and computational, of a detect-and-activate-the-heater protection technique applied to a magnesium diboride (MgB2) test coil operated in semi-persistent mode. The test coil with a winding ID of 25 cm and wound with ~500-m long reacted MgB2 wire was operated at 4.2 K immersed in a bath of liquid helium. In this active technique, upon the initiation of a “hot spot” of a length ~10 cm, induced by a “quench heater,” a “protection heater” (PH) of ~600-cm long planted within the test coil is activated. The normal zone created by the PH is large enough to absorb the test coil’s entire initial stored energy and still keeps the peak temperature within the winding below ~260 K. PMID:22081754

Latest status of the Japanese LCT coil and the domestic test facility

International Nuclear Information System (INIS)

Shimamoto, S.; Ando, T.; Hiyama, T.

1981-01-01

The Japan Atomic Energy Research Institute (JAERI), representing Japan, is now making one of six test coils for the International Energy Agency's (IEA) Large Coil Task(LCT). The Japanese LCT coil, which has a stored energy of 120 MJ, is based on a NgTi conductor, is pool-cooled, has a maximum field of 8T, and is edgewise, double-pancake wound, was completed in October, 1981. The LCT coil will be tested in the newly constructed domestic test facility up to its rated current in November, 1981, before transportation ORNL. The domestic test facility, which is composed of a cryogenic system a vacuum system, a power supply with protection system, and a data acqusition and control system, was completed and its performance measured at a new building for the LCT test at JSAERI in June, 1981. This paper describes the latest construction status of the Japanese LCT coil and the domestic test facility. The performance of the domestic test facility is described in this paper

Test results of the SMES model coil. Cool-down and thermal characteristics

International Nuclear Information System (INIS)

Hamada, Kazuya; Kato, Takashi; Kawano, Katsumi

1998-01-01

A model coil of a superconducting magnetic energy storage (SMES) device, which is a forced-cooled Nb-Ti coil, has been fabricated and a performance test at cryogenic temperatures has been carried out. The SMES model coil is composed of 4 dual pancakes and its total weight is 4.5 t. The applied conductors are cable-in-conduit conductors cooled by supercritical helium (SHe) at 4.5 K and 0.7 MPa. SHe is supplied to the SMES model coil and the structure by a reciprocating bellows pump. The test facility is located at the International Thermonuclear Experimental Reactor (ITER) common test facility, was constructed for the testing of an ITER central solenoid model coil. In the experiments, cool-down was finished within 10 days under controlled temperature differences in the SMES model coil. During cool-down and 4.5 K operation, pressure drop characteristics of the conductor were measured and the friction factor estimated. The pressure drop characteristics of the SMES model coil were in good agreement with those of the previous cable-in-conduit conductor. During static operation without current, the heat load and refrigerator operation conditions were measured. The heat load of the SMES model coil is 7.5 W, which is within the expected value. (author)

Testing of ITER central solenoid coil insulation in an array

International Nuclear Information System (INIS)

Jayakumar, R.; Martovetsky, N.N.; Perfect, S.A.

1995-01-01

A glass-polyimide insulation system has been proposed by the US team for use in the Central Solenoid (CS) coil of the international Thermonuclear Experimental Reactor (ITER) machine and it is planned to use this system in the CS model coil inner module. The turn insulation will consist of 2 layers of combined prepreg and Kapton. Each layer is 50% overlapped with a butt wrap of prepreg and an overwrap of S glass. The coil layers will be separated by a glass-resin composite and impregnated in a VPI process. Small scale tests on the various components of the insulation are complete. It is planned to fabricate and test the insulation in a 4 x 4 insulated CS conductor array which will include the layer insulation and be vacuum impregnated. The conductor array will be subjected to 20 thermal cycles and 100000 mechanical load cycles in a Liquid Nitrogen environment. These loads are similar to those seen in the CS coil design. The insulation will be electrically tested at several stages during mechanical testing. This paper will describe the array configuration, fabrication: process, instrumentation, testing configuration, and supporting analyses used in selecting the array and test configurations

Frosting and defrosting of air-coils - results from laboratory testing

Energy Technology Data Exchange (ETDEWEB)

Fahlen, P

1997-12-31

Frosting of air-coils is an important factor in the design and operation of air-source heat pumps, heat recovery ventilators, cooling and refrigeration equipment etc. This report presents results from laboratory testing of two brine-cooled air-coils under frosting conditions. The coils have the same number of plane, continuous fins, 4 tube rows with 12 tubes in each row, tube spacing of 50 mm and fin spacing of 3 and 6 mm respectively. The original purpose of the test program was to compare various possible indicators of coil frosting and to analyze the possible effects of different control strategies on coil capacity and the COP of the system (the analysis will be presented in a separate report). Tests involved inlet air temperatures of -7 and +2 degC, variation of humidity between 70 and 100% RH (including simulated rain), velocities in the range 1 to 4 m/s, and specific cooling loads from 50 to 150 W/m{sup 2}. Test results include variations due to frosting of e.g. cooling capacity, COP, air flow and pressure drop, fan power, air outlet temperature and humidity, coil temperature, frost mass, and frosting time. Results also include the subsequently required defrost time, defrost energy and collected mass of defrost water. The frosting process was interrupted when the air flow had decreased to 30% of the original value with a non-frosted coil. The results clearly show the advantage of demand controlled defrosting with variations in frosting time between 2 h with high humidity/high specific cooling load up to, for practical purposes, infinite frosting times with low humidity/low specific cooling load. The accumulated frost mass during one frosting cycle varied from less than 0.02 kg/m{sup 2} up to approximately 0.4 kg/m{sup 2}. 23 refs, 93 figs, 89 tabs

Frosting and defrosting of air-coils - results from laboratory testing

Energy Technology Data Exchange (ETDEWEB)

Fahlen, P.

1996-12-31

Frosting of air-coils is an important factor in the design and operation of air-source heat pumps, heat recovery ventilators, cooling and refrigeration equipment etc. This report presents results from laboratory testing of two brine-cooled air-coils under frosting conditions. The coils have the same number of plane, continuous fins, 4 tube rows with 12 tubes in each row, tube spacing of 50 mm and fin spacing of 3 and 6 mm respectively. The original purpose of the test program was to compare various possible indicators of coil frosting and to analyze the possible effects of different control strategies on coil capacity and the COP of the system (the analysis will be presented in a separate report). Tests involved inlet air temperatures of -7 and +2 degC, variation of humidity between 70 and 100% RH (including simulated rain), velocities in the range 1 to 4 m/s, and specific cooling loads from 50 to 150 W/m{sup 2}. Test results include variations due to frosting of e.g. cooling capacity, COP, air flow and pressure drop, fan power, air outlet temperature and humidity, coil temperature, frost mass, and frosting time. Results also include the subsequently required defrost time, defrost energy and collected mass of defrost water. The frosting process was interrupted when the air flow had decreased to 30% of the original value with a non-frosted coil. The results clearly show the advantage of demand controlled defrosting with variations in frosting time between 2 h with high humidity/high specific cooling load up to, for practical purposes, infinite frosting times with low humidity/low specific cooling load. The accumulated frost mass during one frosting cycle varied from less than 0.02 kg/m{sup 2} up to approximately 0.4 kg/m{sup 2}. 23 refs, 93 figs, 89 tabs

Gamma irradiation testing of prototype ITER in-vessel magnetic pick-up coils

International Nuclear Information System (INIS)

Vermeeren, Ludo; Leysen, Willem

2013-01-01

Highlights: ► We tested five prototype ITER in-vessel coils up to a gamma dose of 72 MGy. ► Before and after irradiation thermal tests were also performed from 30 °C till 130 °C. ► The continuity resistances and the insulation resistances were continuously monitored. ► The observed behavior of all coils was satisfactory in all conditions. ► For the further design the mechanical robustness should be taken into account. -- Abstract: To fulfill the requirements for ITER in-vessel magnetic diagnostics, several coil prototypes have been developed, aiming at minimizing the disturbing effects of temperature gradients and radiation induced phenomena. As a first step in the radiation resistance testing of these prototypes, an in-situ high dose rate gamma radiation test on a selection of prototypes was performed. The aim of this test was to get a first experimental feedback regarding the behavior of the pick-up coil prototypes under radiation. Five prototypes (a coil wound with glass-insulated copper wire, two LTCC coils and two HTCC coils) were irradiated at a dose rate of 46 kGy/h up to a total dose of 72 MGy and at a temperature of 50 °C. During the irradiation, the continuity resistances and the insulation resistances were continuously measured. Before and after irradiation reference data were recorded as a function of temperature (from 30 °C to 130 °C). This paper includes the results of the temperature and irradiation tests and a discussion of the behavior of the prototype coils in terms of electrical and mechanical properties

Local SAR in High Pass Birdcage and TEM Body Coils for Multiple Human Body Models in Clinical Landmark Positions at 3T

Science.gov (United States)

Yeo, Desmond TB; Wang, Zhangwei; Loew, Wolfgang; Vogel, Mika W; Hancu, Ileana

2011-01-01

Purpose To use EM simulations to study the effects of body type, landmark position, and RF body coil type on peak local SAR in 3T MRI. Materials and Methods Numerically computed peak local SAR for four human body models (HBMs) in three landmark positions (head, heart, pelvic) were compared for a high-pass birdcage and a transverse electromagnetic 3T body coil. Local SAR values were normalized to the IEC whole-body average SAR limit of 2.0 W/kg for normal scan mode. Results Local SAR distributions were highly variable. Consistent with previous reports, the peak local SAR values generally occurred in the neck-shoulder area, near rungs, or between tissues of greatly differing electrical properties. The HBM type significantly influenced the peak local SAR, with stockier HBMs, extending extremities towards rungs, displaying the highest SAR. There was also a trend for higher peak SAR in the head-centric and heart-centric positions. The impact of the coil-types studied was not statistically significant. Conclusion The large variability in peak local SAR indicates the need to include more than one HBM or landmark position when evaluating safety of body coils. It is recommended that a HBM with arms near the rungs be included, to create physically realizable high-SAR scenarios. PMID:21509880

''Football'' test coil: a simulated service test of internally-cooled, cabled superconductor

International Nuclear Information System (INIS)

Marston, P.G.; Iwasa, Y.; Thome, R.J.; Hoenig, M.O.

1981-01-01

Internally-cooled, cabled superconductor, (ICCS), appears from small-scale tests to be a viable alternative to pool-boiling cooled superconductors for large superconducting magnets. Potential advantages may include savings in helium inventory, smaller structure and ease of fabrication. Questions remain, however, about the structural performance of these systems. The ''football'' test coil has been designed to simulate the actual ''field-current-stress-thermal'' operating conditions of a 25 ka ICCS in a commercial scale MHD magnet. The test procedure will permit demonstration of the 20 year cyclic life of such a magnet in less than 20 days. This paper describes the design, construction and test of that coil which is wound of copper-stabilized niobium-titanium cable in steel conduit. 2 refs

The B00 model coil in the ATLAS Magnet Test Facility

CERN Document Server

Dudarev, A; ten Kate, H H J; Anashkin, O P; Keilin, V E; Lysenko, V V

2001-01-01

A 1-m size model coil has been developed to investigate the transport properties of the three aluminum-stabilized superconductors used in the ATLAS magnets. The coil, named B00, is also used for debugging the cryogenic, power and control systems of the ATLAS Magnet Test Facility. The coil comprises two double pancakes made of the barrel toroid and end-cap toroid conductors and a single pancake made of the central solenoid conductor. The pancakes are placed inside an aluminum coil casing. The coil construction and cooling conditions are quite similar to the final design of the ATLAS magnets. The B00 coil is well equipped with various sensors to measure thermal and electrodynamic properties of the conductor inside the coils. Special attention has been paid to the study of the current diffusion process and the normal zone propagation in the ATLAS conductors and windings. Special pick-up coils have been made to measure the diffusion at different currents and magnetic field values. (6 refs).

Development of a REBCO HTS magnet for Maglev - repeated bending tests of HTS pancake coils -

Science.gov (United States)

Sugino, Motohikoa; Mizuno, Katsutoshi; Tanaka, Minoru; Ogata, Masafumi

2018-01-01

In the past study, two manufacturing methods were developed that can manufacture pancake coils by using REBCO coated conductors. It was confirmed that the conductors have no electric degradation that caused by the manufacturing method. The durability evaluation tests of the pancake coils were conducted as the final evaluation of the coil manufacturing method in this study. The repeated bending deformation was applied to manufactured pancake coils in the tests. As the results of these tests, it was confirmed that the pancake coils that were manufactured by two methods had the durability for the repeated bending deformation and the coils maintained the appropriate mechanical performance and electric performance. We adopted the fusion bonding method as the coil manufacturing method of the HTS magnet Furthermore, using the prototype pancake coil that was manufactured by the fusion bonding method as a test sample, the repeated bending test under the exited condition was conducted. Thus it was confirmed that the coil manufactured by the fusion bonding method has no degradation of the electricity performance and the mechanical properties even if the repeated bending deformation was applied under the exited condition.

Thermal anchoring of wires in large scale superconducting coil test experiment

International Nuclear Information System (INIS)

Patel, Dipak; Sharma, A.N.; Prasad, Upendra; Khristi, Yohan; Varmora, Pankaj; Doshi, Kalpesh; Pradhan, S.

2013-01-01

Highlights: • We addressed how thermal anchoring in large scale coil test is different compare to small cryogenic apparatus? • We did precise estimation of thermal anchoring length at 77 K and 4.2 K heat sink in large scale superconducting coil test experiment. • We addressed, the quality of anchoring without covering entire wires using Kapton/Teflon tape. • We obtained excellent results in temperature measurement without using GE Varnish by doubling estimated anchoring length. -- Abstract: Effective and precise thermal anchoring of wires in cryogenic experiment is mandatory to measure temperature in milikelvin accuracy and to avoid unnecessary cooling power due to additional heat conduction from room temperature (RT) to operating temperature (OT) through potential, field, displacement and stress measurement instrumentation wires. Instrumentation wires used in large scale superconducting coil test experiments are different compare to cryogenic apparatus in terms of unique construction and overall diameter/area due to errorless measurement in large time-varying magnetic field compare to small cryogenic apparatus, often shielded wires are used. Hence, along with other variables, anchoring techniques and required thermal anchoring length are entirely different in this experiment compare to cryogenic apparatus. In present paper, estimation of thermal anchoring length of five different types of instrumentation wires used in coils test campaign at Institute for Plasma Research (IPR), India has been discussed and some temperature measurement results of coils test campaign have been presented

Quality assurance aspects of the major procurements for the Large Coil Test Facility

International Nuclear Information System (INIS)

Taylor, D.J.; Thompson, P.B.; Ryan, T.L.; Queen, C.C.; Halstead, E.L.; Murphy, J.L.; Wood, R.J.

1983-01-01

The Large Coil Test Facility (LCTF) project is comprised of the test stand, supporting cryogenic systems, instrumentation, data acquisition, and utilities necessary for testing the large superconducting coils of the Large Coil Program (LCP). A significant portion of the facility hardware has been obtained through procurement actions with industrial suppliers. This paper addresses the project's experience in formulation and execution of quality assurance (QA) actions relative to several of the major items procured. Project quality assurance planning and specific features related to procurement activities for several of the more specialized test facility components are described. These component procurements include: (1) the coil test stand's major structural item (the bucking post) purchased from foreign industry; (2) fabrication and testing of high-current power supplies; (3) industrial fabrication of specialized instrumentation (voltage-tap signal conditioning modules); and (4) fabrication, installation, and testing of the liquid helium piping system

submitter 16 T Nb$_{3}$Sn Racetrack Model Coil Test Result

CERN Document Server

Perez, J C; Bajko, M; Bottura, L; Bordini, B; Chiuchiolo, A; De Rijk, G; Ferracin, P; Feuvrier, J; Grosclaude, P; Juchno, M; Rochepault, E; Rysti, J; Sarasola, X

2016-01-01

In the framework of the European project EuCARD, the High Field Magnet project, led by a CERN-CEA collaboration, implied the development of a large aperture Nb$_{3}$Sn dipole magnet called FRESCA2. The magnet uses four double-pancake block-type coils, each about 1.5 m long. In order to characterize strand and cable properties, as well as to qualify the coil fabrication process, CERN started in 2012 the design and fabrication of the Racetrack Model Coil (RMC) magnet, a short model magnet using the same cable as FRESCA2 magnet with only two flat double-pancake coils about 0.8 m long. In 2013, two superconducting coils have been fabricated, making use of two different types of superconductor. In 2014 and 2015, the coils were tested both in a single and in a double-coil configuration in a support structure based on an external aluminum shell pre-loaded with water-pressurized bladders. In this paper, we describe the design of the RMC magnet and its coils, provide the main parameters of the superconductor, and repo...

Thermal and electrical joint test for the helical field coils in the Advanced Toroidal Facility

International Nuclear Information System (INIS)

Brown, R.L.; Johnson, R.L.

1985-01-01

Initial feasibility studies of a number of configurations for the Advanced Toroidal Facility (ATF) resulted in the selection of a resistive copper continuous-coil torsatron as the optimum device considering the physics program, cost, and schedule. Further conceptual design work was directed toward optimization of this configuration and, if possible, a shorter schedule. It soon became obvious that in order to shorten the schedule, a number of design and fabrication activities should proceed in parallel. This was most critical for the vacuum vessel and the helical field (HF) coils. If the HF coils were wound in place on a completed vacuum vessel, the overall schedule would be significantly (greater than or equal to12 months) longer. The approach of parallel scheduel paths requires that the HF coils be segmented into parts of less than or equal to180 0 of poloidal angle and that joints be made on a turn-by-turn basis when the segments are installed. It was obvious from the outset that the compact and complex geometry of the joint design presented a special challenge in the areas of reliability, assembly, maintenance, disassembly, and cost. Also, electrical, thermal, and force excursions are significant for these joints. A number of soldered, welded, brazed, electroplated, and bolted joints were evaluated. The evaluations examined fabrication feasibility and complexity, thermal-electrical performance at approximately two-thirds of the steady-state design conditions, and installation and assembly processes. Results of the thermal-electrical tests were analyzed and extrapolated to predict performance at peak design parameters. The final selection was a lap-type joint clamped with insulated bolts that pass through the winding packing. 3 refs., 4 figs

Testing the Turing Test — do Men Pass It?

Science.gov (United States)

Adam, Ruth; Hershberg, Uri; Schul, Yaacov; Solomon, Sorin

We are fascinated by the idea of giving life to the inanimate. The fields of Artificial Life and Artificial Intelligence (AI) attempt to use a scientific approach to pursue this desire. The first steps on this approach hark back to Turing and his suggestion of an imitation game as an alternative answer to the question "can machines think?".1 To test his hypothesis, Turing formulated the Turing test1 to detect human behavior in computers. But how do humans pass such a test? What would you say if you would learn that they do not pass it well? What would it mean for our understanding of human behavior? What would it mean for our design of tests of the success of artificial life? We report below an experiment in which men consistently failed the Turing test.

Electrical testing and performance evaluation of 1:1 prototype JET ELM control coils

Energy Technology Data Exchange (ETDEWEB)

Kanabar, Deven, E-mail: deven@ipr.res.in; Roy, Swati; Ghate, Mahesh; Raj, Piyush; Kundu, Ananya; Kumar, Nitish; Bhavsar, Dhaval; Panchal, Arun; Pradhan, Subrata, E-mail: pradhan@ipr.res.in

2016-12-15

Highlights: • An appropriate 1:1 prototype Small and Large ELM coils for JET have been successfully manufactured using indigenous technologies. • ELM coils have been tested extensively to verify and validated their performance with respect to operational requirement of JET. • The test results confirm and validate the electrical performance of ELM coils. - Abstract: Magnet Technology Development Division at Institute for Plasma research is engaged in extensive R & D for appropriate technologies towards manufacturing of Edge Localized Mode (ELM) magnets for Large Tokamak such as Joint European Torus (JET) as well as for Steady State Superconducting Tokamak (SST-1). Under this project, manufacturing of 1:1 prototype of Large and Small JET ELM control coils (CC) is completed incorporating indigenously developed manufacturing and insulation technologies. Performance evaluation of both the types of coil has been completed for its current carrying capability and insulation resistance as required by various operational scenarios of JET. Experimental setups, test procedures and measurements for electrical characterization of both type of ELM control coil has been discussed in this paper.

Electrical testing and performance evaluation of 1:1 prototype JET ELM control coils

International Nuclear Information System (INIS)

Kanabar, Deven; Roy, Swati; Ghate, Mahesh; Raj, Piyush; Kundu, Ananya; Kumar, Nitish; Bhavsar, Dhaval; Panchal, Arun; Pradhan, Subrata

2016-01-01

Highlights: • An appropriate 1:1 prototype Small and Large ELM coils for JET have been successfully manufactured using indigenous technologies. • ELM coils have been tested extensively to verify and validated their performance with respect to operational requirement of JET. • The test results confirm and validate the electrical performance of ELM coils. - Abstract: Magnet Technology Development Division at Institute for Plasma research is engaged in extensive R & D for appropriate technologies towards manufacturing of Edge Localized Mode (ELM) magnets for Large Tokamak such as Joint European Torus (JET) as well as for Steady State Superconducting Tokamak (SST-1). Under this project, manufacturing of 1:1 prototype of Large and Small JET ELM control coils (CC) is completed incorporating indigenously developed manufacturing and insulation technologies. Performance evaluation of both the types of coil has been completed for its current carrying capability and insulation resistance as required by various operational scenarios of JET. Experimental setups, test procedures and measurements for electrical characterization of both type of ELM control coil has been discussed in this paper.

Mechanical behavior of the mirror fusion test Facility superconducting magnet coils

International Nuclear Information System (INIS)

Horvath, J.A.

1980-01-01

The mechanical response to winding and electromagnetic loads of the Mirror Fusion Test Facility (MFTF) superconducting coil pack is presented. The 375-ton (3300 N) MFTF Yin-Yang magnet, presently the world's largest superconducting magnet, is scheduled for acceptance cold-testing in May of 1981. The assembly is made up of two identical coils which together contain over 15 miles (24 km) of superconductor wound in 58 consecutive layers of 24 turns each. Topics associated with mechanical behavior include physical properties of the coil pack and its components, winding pre-load effects, finite element analysis, magnetic load redistribution, and the design impact of predicted conductor motion

Superconducting coil system and methods of assembling the same

Science.gov (United States)

Rajput-Ghoshal, Renuka; Rochford, James H.; Ghoshal, Probir K.

2016-01-19

A superconducting magnet apparatus is provided. The superconducting magnet apparatus includes a power source configured to generate a current; a first switch coupled in parallel to the power source; a second switch coupled in series to the power source; a coil coupled in parallel to the first switch and the second switch; and a passive quench protection device coupled to the coil and configured to by-pass the current around the coil and to decouple the coil from the power source when the coil experiences a quench.

Quench and protection characteristics of the GEM test coil

International Nuclear Information System (INIS)

Chaniotakis, E.A.; Marston, P.G.

1994-01-01

The GEM test coil, will be wound from 70 m of conductor identical to that used in the full scale magnet. The coil configuration will duplicate the field distribution of the full scale magnet and current control will duplicate full scale current decay characteristics. Therefore, quench/protection analysis of this coil will reveal very important information about the behavior of the full scale model. Due to the uncertainty associated with the contact between the cable, the conduit and the sheath, a parametric analysis has been performed in order to determine and bracket the behavior. With no electrical contact the quench evolves normally until, due to heat transfer from the sheath into the cable, the superconductor temperature becomes critical and the entire length becomes normal

Testing of a Single 11 T $Nb_3Sn$ Dipole Coil Using a Dipole Mirror Structure

Energy Technology Data Exchange (ETDEWEB)

Zlobin, Alexander [Fermilab; Andreev, Nicolai [Fermilab; Barzi, Emanuela [Fermilab; Chlachidze, Guram [Fermilab; Kashikhin, Vadim [Fermilab; Nobrega, Alfred [Fermilab; Novitski, Igor [Fermilab; Turrioni, Daniele [Fermilab; Karppinen, Mikko [CERN; Smekens, David [CERN

2014-07-01

FNAL and CERN are developing an 11 T Nb3Sn dipole suitable for installation in the LHC. To optimize coil design parameters and fabrication process and study coil performance, a series of 1 m long dipole coils is being fabricated. One of the short coils has been tested using a dipole mirror structure. This paper describes the dipole mirror magnetic and mechanical designs, and reports coil parameters and test results.

Quench and safety tests on a toroidal field coil of Tore Supra

International Nuclear Information System (INIS)

Ciazynski, D.; Cure, C.; Duchateau, J.L.

1987-01-01

As a part of the safety analysis of the magnet, three quenches have been initiated in one of the TF coils in the Saclay test facility. While transporting a given current, the coil is insulated from the refrigerator: the temperatures of the helium and of the coil increase slowly on account of thermal losses. At the current sharing temperature a quench rapidly propagates and the protection system makes the coil discharge in the dump resistor. At three levels of current, electrical, thermal and hydraulic measurements have been performed. All these results are taken into account for the safety design of TORE SUPRA

Construction and Test Results of Coils 2 and 3 of a 3-Nested-Coil 800-MHz REBCO Insert for the MIT 1.3-GHz LTS/HTS NMR Magnet.

Science.gov (United States)

Park, Dongkeun; Bascuñán, Juan; Michael, Philip C; Lee, Jiho; Hahn, Seungyong; Iwasa, Yukikazu

2018-04-01

We present construction and test results of Coils 2 and 3 of a 3-coil 800-MHz REBCO insert (H800) for the MIT 1.3 GHz LTS/HTS NMR magnet currently under construction. Each of three H800 coils (Coils 1-3) is a stack of no-insulation REBCO double pancakes (DPs). The innermost 8.67-T Coil 1 (26 DPs) was completed in 2016; the middle 5.64-T Coil 2 (32 DPs) has been wound, assembled, and tested; and for the outermost 4.44-T Coil 3, its 38 DPs have been wound and preliminary tests were performed to characterize each DP at 77 K. Included for Coil 2 are: 1) 77-K data of critical current, index, and turn-to-turn characteristic resistivity of each DP; 2) stacking order of the 32 DPs optimized to maximize the Coil 2 current margin and minimize its Joule dissipation in the pancake-to-pancake joints; 3) procedure to experimentally determine and apply a room-temperature preload to the DP stack; 4) 77-K and 4.2-K test results after each of 64 pancakes was over-banded with 75-μm-thick stainless steel tape for a radial thickness of 5 mm. Presented for each DP in Coil 3 are 77-K dada of critical current, index, and turn-to-turn characteristic resistivity.

Three dimensional numeric quench simulation of Super-FRS dipole test coil for FAIR project

International Nuclear Information System (INIS)

Wu Wei; Ma Lizhen; He Yuan; Yuan Ping

2013-01-01

The prototype of superferric dipoles for Super-FRS of Facility for Antiprotons and Ion Research (FAIR) project was designed, fabricated, and tested in China. To investigate the performance of the superconducting coil, a so-called test coil was fabricated and tested in advance. A 3D model based on ANSYS and OPERA 3D was developed in parallel, not only to check if the design matches the numerical simulation, but also to study more details of quench phenomena. The model simplifies the epoxy impregnated coil into an anisotropic continuum medium. The simulation combines ANSYS solver routines for nonlinear transient thermal analysis, the OPERA 3D for magnetic field evaluation and the ANSYS script language for calculations of Joule heat and differential equations of the protection circuits. The time changes of temperature, voltage and current decay, and quench propagation during quench process were analyzed and illustrated. Finally, the test results of the test coil were demonstrated and compared with the results of simulation. (authors)

Test of Optimized 120-mm LARP $Nb_{3}S_n$ Quadrupole Coil Using Magnetic Mirror Structure

CERN Document Server

Chlachidze, G; Andreev, N; Anerella, M; Barzi, E; Bossert, R; Caspi, S; Cheng, D; Dietderich, D; Felice, H; Ferracin, P; Ghosh, A; Godeke, A; Hafalia, A R; Kashikhin, V V; Lamm, M; Marchevsky, M; Nobrega, A; Novitski, I; Orris, D; Sabbi, G L; Schmalzle, J; Wanderer, P; Zlobin, A V

2013-01-01

The US LHC accelerator research program (LARP) is developing a new generation of large - aperture high - field quadrupoles based on Nb 3 Sn conductor for the High luminosity upgrade of Large Hadron Collider (HiLumi - LHC). Tests of the first series of 120 - mm aperture HQ coils revealed the necessity for further optimization of the coil design and fabrication process. Modifications in coil design were gradually implemented in two HQ coils previously tested at Fermi National Accelerato r Laboratory (Fermilab) using a magnetic mirror structure (HQM01 and HQM02). This paper describes the construction and test of an HQ mirror model with a coil of optimized design and with an interlayer resistive core in the conductor. The cable for this co il was made of a smaller diameter strand, providing more room for coil expansion during reaction. The 0.8 - mm strand, used in all previous HQ coils was replaced with a 0.778 - mm Nb 3 Sn strand of RRP 108/127 sub - element design. The coil was instrumented with voltage taps, h...

Upgrade of DC power supply system in ITER CS model coil test facility

International Nuclear Information System (INIS)

Shimono, Mitsugu; Uno, Yasuhiro; Yamazaki, Keita; Kawano, Katsumi; Isono, Takaaki

2014-03-01

Objective of the ITER CS Model Coil Test Facility is to evaluate a large scale superconducting conductor for fusion using the Central Solenoid (CS) Model Coil, which can generate a 13T magnetic field in the inner bore with a 1.5 m diameter. The facility is composed of a helium refrigerator / liquefier system, a DC power supply system, a vacuum system and a data acquisition system. The DC power supply system supplies currents to two superconducting coils, the CS Model Coil and an insert coil. A 50-kA DC power supply is installed for the CS Model Coil and two 30 kA DC power supplies are installed for an insert coil. In order to evaluate superconducting performance of a conductor used for ITER Toroidal Field (TF) coils whose operating current is 68 kA, the line for an insert coil is upgraded. A 10 kA DC power supply was added, DC circuit breakers were upgraded, bus bars and current measuring instrument were replaced. In accordance to the upgrade, operation manual was revised. (author)

Using a modified 3D-printer for mapping the magnetic field of RF coils designed for fetal and neonatal imaging.

Science.gov (United States)

Vavoulas, Alexander; Vaiopoulos, Nicholas; Hedström, Erik; Xanthis, Christos G; Sandalidis, Harilaos G; Aletras, Anthony H

2016-08-01

An experimental setup for characterizing the magnetic field of MRI RF coils was proposed and tested. The setup consisted of a specially configured 3D-printer, a network analyzer and a mid-performance desktop PC. The setup was tested on a single loop RF coil, part of a phased array for fetal imaging. Then, the setup was used for determining the magnetic field characteristics of a high-pass birdcage coil used for neonatal MR imaging with a vertical static field. The scattering parameter S21, converted into power ratio, was used for mapping the B1 magnetic field. The experimental measurements from the loop coil were close to the theoretical results (R=0.924). A high degree of homogeneity was measured for the neonatal birdcage RF coil. The development of MR RF coils is time consuming and resource intensive. The proposed experimental setup provides an alternative method for magnetic field characterization of RF coils used in MRI. Copyright © 2016 Elsevier Inc. All rights reserved.

A design for a high voltage magnet coil ringer test set

International Nuclear Information System (INIS)

Koska, W.; Sims, R.E.

1992-04-01

By discharging a bank of charged capacitors through a high power SCR switch into an SSC dipole magnet assembly, it is possible to ''ring'' the coil and develop a voltage stress of greater than 50 volts turn-to-turn, thereby verifying the insulation integrity. We will present an overview of the test set design for a 2 kV isolated SCR firing circuit, including safety features, selectable capacitor banks, and digital waveform storage system. Results from testing typical coils and magnets will be included. Possible upgrades are also discussed

Forces on a magnet moving past figure-eight coils

International Nuclear Information System (INIS)

Mulcahy, T.H.; He, Jianliang; Rote, D.M.; Rossing, T.D.

1993-01-01

For the first time, the lift, drag, and guidance forces acting on a permanent magnet are measured as the magnet passes over different arrays of figure-eight (null-flux) coils. The experimental results are in good agreement with the predictions of dynamic circuit theory, which is used to explain more optimal coil arrays

Design and testing of a coil-unit barrel for helical coil electromagnetic launcher

Science.gov (United States)

Yang, Dong; Liu, Zhenxiang; Shu, Ting; Yang, Lijia; Ouyang, Jianming

2018-01-01

A coil-unit barrel for a helical coil electromagnetic launcher is described. It provides better features of high structural strength and flexible adjustability. It is convenient to replace the damaged coil units and easy to adjust the number of turns in the stator coils due to the modular design. In our experiments, the highest velocity measured for a 4.5-kg projectile is 47.3 m/s and the mechanical reinforcement of the launcher could bear 35 kA peak current. The relationship between the energy conversion efficiency and the inductance gradient of the launcher is also studied. In the region of low inductance gradient, the efficiency is positively correlated with the inductance gradient. However, in the region of high inductance gradient, the inter-turn arc erosion becomes a major problem of limiting the efficiency and velocity of the launcher. This modular barrel allows further studies in the inter-turn arc and the variable inductance gradient helical coil launcher.

Status of the cold test facility for the JT-60SA tokamak toroidal field coils

Energy Technology Data Exchange (ETDEWEB)

Abdel Maksoud, Walid, E-mail: walid.abdelmaksoud@cea.fr; Bargueden, Patrick; Bouty, André; Dispau, Gilles; Donati, André; Eppelle, Dominique; Genini, Laurent; Guiho, Patrice; Guihard, Quentin; Joubert, Jean-Michel; Kuster, Olivier; Médioni, Damien; Molinié, Frédéric; Sinanna, Armand; Solenne, Nicolas; Somson, Sébastien; Vieillard, Laurence

2015-10-15

Highlights: • The 5 K cryogenic loop includes a 500 W refrigerator and a She cold pump. • The coils are energized thanks to a 25.7 kA power supply and HTS current leads. • Temperature margin tests between 5 K and 7.5 K will be made on each coil. • A magnet safety system protects each double pancake of the coil in case of quench. • Instrumentation is monitored on a 1 Hz to 10 kHz fast acquisition system. - Abstract: JT-60SA is a fusion experiment which is jointly constructed by Japan and Europe and which shall contribute to the early realization of fusion energy, by providing support to the operation of ITER, and by addressing key physics issues for ITER and DEMO. In order to achieve these goals, the existing JT-60U experiment will be upgraded to JT-60SA by using superconducting coils. The 18 TF coils of the JT-60SA device will be provided by European industry and tested in a Cold Test Facility (CTF) at CEA Saclay. The coils will be tested at the nominal current of 25.7 kA and will be cooled with supercritical helium between 5 K and 7.5 K to check the temperature margin against a quench. The main objective of these tests is to check the TF coils performance and hence mitigate the fabrication risks. The most important components of the facility are: a 11.5 m × 6.5 m large cryostat in which the TF coils will be thermally insulated by vacuum; a 500 W helium refrigerator and a valve box to cool the coils down to 5 K and circulate 24 g/s of supercritical helium through the winding pack and through the casing; a power supply and HTS current leads to energize the coil; the control and instrumentation equipment (sensors, PLC's, supervision system, fast data acquisition system, etc.) and the Magnet Safety System (MSS) that protects the coils in case of quench. The paper will give an overview of the design of this large facility and the status of its realization.

Development work on superconducting coils for a Large Mirror Fusion Test Facility

International Nuclear Information System (INIS)

Cornish, D.N.; Deis, D.W.; Harvey, A.R.; Hirzel, D.G.; Johnston, J.E.; Leber, R.L.; Nelson, R.L.; Zbasnik, J.P.

1977-01-01

This article has summarized development work directed toward obtaining the data required to design and build the superconducting coils for MFTF. The methods for fabricating the conductor and joining lengths of the conductor are almost finalized, and the building of the test coil and associated equipment is now well under way

Manufacture of mineral-insulated conductor for ITER prototype ELM and VS coil

International Nuclear Information System (INIS)

Long, Feng; Wu, Yu; Jin, Huan; Yu, Min; Han, Qiyang; Ling, Feng; Kalish, Michael

2015-01-01

Highlights: • Compaction method is successfully developed for MIC manufacture. • Manufactured MICs show well controlled outer diameter and good electrical properties. • Insulation resistance of all the MICs is higher than 100 GΩ@DC 2500 V. - Abstract: An ITER Organization (IO) Task Agreement (TA) “Final Design and Prototyping of the ITER In-Vessel Coils (IVC) and Feeders” is almost finished by Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). ITER IVCs consist of edge-localized mode (ELM) and vertical stabilization (VS) coils. One prototype Mid-ELM coil complete with 19 brackets brazed with the conductors and one prototype 120° section of upper VS coil with structural components brazed to the conductors have been fabricated. Compaction method is developed successfully for the mineral-insulated conductor (MIC) manufacture. Approximate 110 m Inconel 625 jacket MICs for Mid-ELM prototype coil and 80 m stainless steel 316L jacket MICs for VS prototype coil were manufactured. Most of the copper tubes used for the MICs fabrication failed the ultrasonic testing (UT), but the jacket tubes have good passing rate. Manufacture processes and inspection for the MICs are presented in this paper

Manufacture of mineral-insulated conductor for ITER prototype ELM and VS coil

Energy Technology Data Exchange (ETDEWEB)

Long, Feng, E-mail: longf@ipp.ac.cn [Institute of Plasma Physics of Chinese Academy of Sciences, Hefei 230031 (China); Wu, Yu; Jin, Huan; Yu, Min; Han, Qiyang; Ling, Feng [Institute of Plasma Physics of Chinese Academy of Sciences, Hefei 230031 (China); Kalish, Michael [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, NJ 08543 (United States)

2015-06-15

Highlights: • Compaction method is successfully developed for MIC manufacture. • Manufactured MICs show well controlled outer diameter and good electrical properties. • Insulation resistance of all the MICs is higher than 100 GΩ@DC 2500 V. - Abstract: An ITER Organization (IO) Task Agreement (TA) “Final Design and Prototyping of the ITER In-Vessel Coils (IVC) and Feeders” is almost finished by Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). ITER IVCs consist of edge-localized mode (ELM) and vertical stabilization (VS) coils. One prototype Mid-ELM coil complete with 19 brackets brazed with the conductors and one prototype 120° section of upper VS coil with structural components brazed to the conductors have been fabricated. Compaction method is developed successfully for the mineral-insulated conductor (MIC) manufacture. Approximate 110 m Inconel 625 jacket MICs for Mid-ELM prototype coil and 80 m stainless steel 316L jacket MICs for VS prototype coil were manufactured. Most of the copper tubes used for the MICs fabrication failed the ultrasonic testing (UT), but the jacket tubes have good passing rate. Manufacture processes and inspection for the MICs are presented in this paper.

The IEA Large Coil Task

International Nuclear Information System (INIS)

Beard, D.S.; Klose, W.; Shimamoto, S.; Vecsey, G.

1988-01-01

A multinational program of cooperative research, development, demonstrations, and exchanges of information on superconducting magnets for fusion was initiated in 1977 under an IEA agreement. The first major step in the development of TF magnets was called the Large Coil Task. Participants in LCT were the U.S. DOE, EURATOM, JAERI, and the Departement Federal de l'Interieur of Switzerland. The goals of LCT were to obtain experimental data, to demonstrate reliable operation of large superconducting coils, and to prove design principles and fabrication techniques being considered for the toroidal magnets of thermonuclear reactors. These goals were to be accomplished through coordinated but largely independent design, development, and construction of six test coils, followed by collaborative testing in a compact toroidal test array at fields of 8 T and higher. Under the terms of the IEA Agreement, the United States built and operated the test facility at Oak Ridge and provided three test coils. The other participants provided one coil each. Information on design and manufacturing and all test data were shared by all. The LCT team of each participant included a government laboratory and industrial partners or contractors. The last coil was completed in 1985, and the test assembly was completed in October of that year. Over the next 23 months, the six-coil array was cooled down and extensive testing was performed. Results were gratifying, as tests achieved design-point performance and well beyond. (Each coil reached a peak field of 9 T.) Experiments elucidated coil behavior, delineated limits of operability, and demonstrated coil safety. (orig./KP)

Eddy-current testing of nuclear fuel cladding tubes using tilted encircling coil system, 1

International Nuclear Information System (INIS)

Yin, Renzhong; Sekine, Kazuyoshi; Shimizu, Hisaji; Tsukui, Kazushige; Urata, Megumu.

1989-01-01

The eddy current testing method with external encircling-coils has been widely used as a standard technique for inspection of defects in irradiated zircaloy cladding tubes. In this inspection, the systematic procedure to reliably characterize defects is required. This paper describes the newly developed external tilted encircling-coil system, in which the coil axis is inclined by an angle α to the sample tube axis, for reliable determination of the sort, location and size of defects. As the results of experimental work concerning some kinds of artificial defects in zircaloy cladding tubes using newly designed tilted coil system, an adaptable general-procedure for characterization of defects has been proposed. Furthermore, it has been confirmed that in the case of smaller tilt angles of coil, the signal-to noise ratio for defect response in this coil system is approximately equal to that of ordinary encircling coil system. (author)

The First ATLAS Barrel Toroid Coil Successfully Tested in Hall 180

CERN Multimedia

Rabbers, J J

2004-01-01

The first Barrel Toroid coil has been successfully tested with magnetic mirror at nominal current I=20.5 kA, up to a maximum current Imax=22 kA. After 14 days of cooling down, BT1 reached 4.5 Kelvin and the test program started on September 2nd. First the instrumentation and safety systems of the coil were tested at relatively low operating currents, up to 5 kA. Since all the systems and the coil were performing well, the current was increased by steps in several runs, while monitoring and evaluating the temperatures, voltages and mechanics. On early Wednesday morning September 8th the current was ramped up to 22 kA, shown by the red curve in the picture shown below: Thereafter the current was ramped down by a slow dump, where the stored energy of about 130 MJ is dissipated in a resistor/diode ramp down unit. This is the regular way of ramping down the current, which takes about one hour. Thereafter the current was ramped up to 22 kA for a second time, this time a so-called fast dump was initiated, ...

Manufacture of the poloidal field conductor insert coil (PFCI)

Energy Technology Data Exchange (ETDEWEB)

Baker, W. [EFDA CSU Garching, Boltzmannstrasse 2, 85748 Garching bei Muenchen (Germany); Keefe, C. [Tesla Engineering, Storrington, Sussex (United Kingdom); Rajainmaeki, H. [EFDA CSU Garching, Boltzmannstrasse 2, 85748 Garching bei Muenchen (Germany)], E-mail: hannu.rajainmaki@tech.efda.org; Salpietro, E. [EFDA CSU Garching, Boltzmannstrasse 2, 85748 Garching bei Muenchen (Germany)

2007-10-15

Within the framework of the R and D programme for international thermonuclear experimental reactor (ITER) the European team European Fusion Development Agreement (EFDA) has been charged with the design and manufacture of the poloidal field conductor insert coil (PFCI). The purpose of the PFCI is to test and demonstrate the performance of long-length full-scale NbTi conductors in ITER-relevant conditions. The PFCI will be tested in the central solenoid model coil test facility at the JAEA, Naka, Japan. This paper details the complete manufacturing of the PFCI including development, forming machining, pre-assembly, impregnation, final assembly and testing. The PFCI is a single-layered wound solenoid of nine turns with a transition joggle in the centre section of the winding and an intermediate joint connection between the upper termination and the main coil winding. To give the required overall dimensions to fit in the testing facility, preformed and machined glass resin composite filler pieces are assembled with the winding and is finally vacuum pressure impregnated (VPI) to create a single assembly unit. The PFCI is enclosed for assembly in a support structure, which consists of an upper and lower flange, each made up of four electrically insulated machined stainless steel castings, and 12 tie rods preloading the complete assembly in the vertical direction. The upper flange is equipped with four radial restraining jacks and the lower flange is equipped with four sets of studs and shear keys to withstand the net vertical and lateral electromagnetic forces. The PFCI is equipped with inductive heaters, voltage taps, temperature transducers, strain gauges and other instrumentation as diagnostics to monitor the performance. The current status of the manufacture is that the coil has passed the final acceptance tests and it is in the support structure assembly stage.

ITER toroidal field model coil (TFMC). Test and analysis summary report (testing handbook) chapter 3 TOSKA FACILITY

International Nuclear Information System (INIS)

Ulbricht, A.

2001-05-01

In the frame of a contract between the ITER (International Thermonuclear Experimental Reactor) Director and the European Home Team Director was concluded the extension of the TOSKA facility of the Forschungszentrum Karlsruhe as test bed for the ITER toroidal field model coil (TFMC), one of the 7 large research and development projects of the ITER EDA (Engineering Design Activity). The report describes the work and development, which were performed together with industry to extend the existing components and add new components. In this frame a new 2 kW refrigerator was added to the TOSKA facility including the cold lines to the Helium dewar in the TOSKA experimental area. The measuring and control system as well as data acquisition was renewed according to the state-of-the-art. Two power supplies (30 kA, 50 kA) were switched in parallel across an Al bus bar system and combined with an 80 kA dump circuit. For the test of the TFMC in the background field of the EURATOM LCT coil a new 20 kA power supply was taken into operation with the existing 20 kA discharge circuit. Two forced flow cooled 80 kA current leads for the TFMC were developed. The total lifting capacity for loads in the TOSKA building was increased by an ordered new 80 t crane with a suitable cross head (125 t lifting capacity +5 t net mass) to 130 t for assembling and installation of the test arrangement. Numerous pre-tests and development and adaptation work was required to make the components suitable for application. The 1.8 K test of the EURATOM LCT coil and the test of the W 7-X prototype coil count to these tests as overall pre-tests. (orig.)

Traveling-wave synchronous coil gun

International Nuclear Information System (INIS)

Elliott, D.G.

1991-01-01

This paper reports on a traveling-wave synchronous coil gun which permits independent adjustment of the magnetic field and armature current for high velocity at low armature mass fraction. Magnetic field energy is transferred from the rear of the wave to the front without passing through the power supply. Elaborate switching is required

Eddy current testing probe with dual half-cylindrical coils

Science.gov (United States)

Bae, Byung-Hoon; Choi, Jung-Mi; Kim, Soo-Yong

2000-02-01

We have developed a new eddy current probe composed of a dual half-cylindrical (2HC) coil as an exciting coil and a sensing coil that is placed in the small gap of the 2HC coil. The 2HC coil induces a linear eddy current on the narrow region within the target medium. The magnitude of eddy current has a maximum peak with the narrow width, underneath the center of the exciting 2HC coil. Because of the linear eddy current, the probe can be used to detect not only the existence of a crack but also its direction in conducting materials. Using specimen with a machined crack, and varying the exciting frequency from 0.5 to 100 kHz, we investigated the relationships between the direction of crack and the output voltage of the sensing coil.

Coil winder for the magnet of the mirror fusion test facility

International Nuclear Information System (INIS)

Ling, R.C.

1977-01-01

A coil winder was designed for the purpose of fabricating the superconducting magnets of the Mirror Fusion Test Facility. The superconducting magnets are a displaced ying-yang pair, each having major and minor radii of 2.5 and 0.75 m, respectively, and cross section of 0.42 m by about 1.03 m. The superconductor cross section is a square, 13 mm on a side, and consists of a core of niobium-titanium embedded copper and a solid copper stabilizer. Conceptual studies made at Lawrence Livermore Laboratory of the coil winder resulted in concept drawings and a procurement specification. Final design was made by the contractor, and the coil winder is now in fabrication. This paper describes the performance requirements of the winder, and the evolution of its design from conceptual stage to completion

TFTR toroidal field coil design

International Nuclear Information System (INIS)

Smith, G.E.; Punchard, W.F.B.

1977-01-01

The design of the Tokamak Fusion Test Reactor (TFTR) Toroidal Field (TF) magnetic coils is described. The TF coil is a 44-turn, spiral-wound, two-pancake, water-cooled configuration which, at a coil current of 73.3 kiloamperes, produces a 5.2-Tesla field at a major radius of 2.48 meters. The magnetic coils are installed in titanium cases, which transmit the loads generated in the coils to the adjacent supporting structure. The TFTR utilizes 20 of these coils, positioned radially at 18 0 intervals, to provide the required toroidal field. Because it is very highly loaded and subject to tight volume constraints within the machine, the coil presents unique design problems. The TF coil requirements are summarized, the coil configuration is described, and the problems highlighted which have been encountered thus far in the coil design effort, together with the development tests which have been undertaken to verify the design

Large coil program support structure conceptual design

International Nuclear Information System (INIS)

Litherland, P.S.

1977-01-01

The purpose of the Large Coil Program (LCP) is to perform tests on both pool boiling and force cooled superconducting toroidal field coils. The tests will attempt to approximate conditions anticipated in an ignition tokamak. The test requirements resulted in a coil support design which accommodates up to six (6) test coils and is mounted to a structure capable of resisting coil interactions. The steps leading to the present LCP coil support structure design, details on selected structural components, and the basic assembly sequence are discussed

Statistical Requirements For Pass-Fail Testing Of Contraband Detection Systems

International Nuclear Information System (INIS)

Gilliam, David M.

2011-01-01

Contraband detection systems for homeland security applications are typically tested for probability of detection (PD) and probability of false alarm (PFA) using pass-fail testing protocols. Test protocols usually require specified values for PD and PFA to be demonstrated at a specified level of statistical confidence CL. Based on a recent more theoretical treatment of this subject [1], this summary reviews the definition of CL and provides formulas and spreadsheet functions for constructing tables of general test requirements and for determining the minimum number of tests required. The formulas and tables in this article may be generally applied to many other applications of pass-fail testing, in addition to testing of contraband detection systems.

Standardized Testing Practices: Effect on Graduation and NCLEX® Pass Rates.

Science.gov (United States)

Randolph, Pamela K

The use standardized testing in pre-licensure nursing programs has been accompanied by conflicting reports of effective practices. The purpose of this project was to describe standardized testing practices in one states' nursing programs and discover if the use of a cut score or oversight of remediation had any effect on (a) first time NCLEX® pass rates, (b) on-time graduation (OTG) or (c) the combination of (a) and (b). Administrators of 38 nursing programs in one Southwest state were sent surveys; surveys were returned by 34 programs (89%). Survey responses were compared to each program's NCLEX pass rate and on-time graduation rate; t-tests were conducted for significant differences associated with a required minimum score (cut score) and oversight of remediation. There were no significant differences in NCLEX pass or on-time graduation rates related to establishment of a cut score. There was a significant difference when the NCLEX pass rate and on-time graduation rate were combined (Outcome Index "OI") with significantly higher program outcomes (P=.02.) for programs without cut-scores. There were no differences associated with faculty oversight of remediation. The results of this study do not support establishment of a cut-score when implementing a standardized testing. Copyright © 2016. Published by Elsevier Inc.

LCT-coil design: Mechanical interaction between composite winding and steel casing under various test conditions

International Nuclear Information System (INIS)

Dolensky, B.; Messemer, G.; Zehlein, H.; Erb, J.

1981-01-01

Finite element computations for the structural design of the large superconducting toroidal field coil contributed by EURATOM to the Large Coil Test Facility (LCTF) at ORNL, USA were performed at KfK, using the ASKA code. The layout of the coil must consider different types of requirements: firstly, an optimal D-shaped contour minimizing circumferential stress gradients under normal operation in the toroidal arrangement must be defined. Secondly, the three-dimensional real design effects due to the actual support conditions, manufacturing tolerances etc. must be mastered for different basic operational and failure load cases. And, thirdly, the design must stand a single coil qualification test in the TOSKA-facility at KfK, Karlsruhe, FRG, before it is plugged into the LCTF. The emphasis of the paper is three-pronged according to these requirements: i) the 3D magnetic body forces as well as the underlying magnetic fields as computed by the HEDO-code are described. ii) The mechanical interaction between casing and winding as given elsewhere in terms of high stress regions, gaps, slide movements and contact forces for various load cases representing the LCTF test conditions is illustrated here by a juxtaposition of the operational deformations and stresses within the LCTF and the TOSKA. iii) Particular effects like the restraint imposed by a corset-type reinforcement of the coil in the TOSKA test facility to limit the breathing deformation are parametrically studied. Moreover, the possibilities to derive scaling laws which make essential results transferable to larger coils by extracting a 1D mechanical response from the 3D finite element model is also demonstrated. (orig./GG)

First full-size ATLAS barrel toroid coil successfully tested up to 22 kA at 4 T

CERN Document Server

Dudarev, A; Benoit, P; Berriaud, C P; Broggi, F; Deront, L; Foussat, A; Junker, S; ten Kate, H H J; Kopeykin, N; Olesen, G; Olyunin, A; Pengo, R; Rabbers, J J; Ravat, S; Rey, J M; Sbrissa, E; Shugaev, I; Stepanov, V; Védrine, P; Volpini, Giovanni

2005-01-01

The Superconducting Barrel Toroid is providing (together with the two End-Cap Toroids not presented here) the magnetic field for the muon detectors in the ATLAS Experiment at the LHC at CERN. The toroid with outer dimensions of 25 m length and 20 m diameter, is built up from 8 identical racetrack coils. The coils with 120 turns each are wound with an aluminum stabilized NbTi conductor and operate at 20.5 kA at 3.9 T local field in the windings and is conduction cooled at 4.8 K by circulating forced flow helium in cooling tubes attached to the cold mass. The 8 coils of 25 m * 5 m are presently under construction and the first coils have already been fully integrated and tested. Meanwhile the assembly of the toroid 100 m underground in the ATLAS cavern at CERN has started. The 8 coils are individually tested on surface before installation. In this paper the test of the first coil, unique in size and manufacturing technology, is described in detail and the results are compared to the previous experience with the...

Superconducting cyclotron magnet coil short

International Nuclear Information System (INIS)

Mallory, M.L.; Blosser, H.G.; Clark, D.J.; Launer, H.; Lawton, D.; Miller, P.; Resmini, F.

1982-01-01

In February 1981, a short circuit appeared in the superconducting coil of the K500 cyclotron. The short is resistive in character and therefore has no effect on steady state operation of the magnet. The resistance of the short varies, sometimes being below threshold of detection as a heat load on the cooling system and sometimes being significant. The resistance under certain conditions shows approximately cyclic phenomena with time constants in the range of seconds and other approximately cyclic phenomena which correlate with gross operating parameters of the magnet (shifting current from one coil to another at high field and lowering and raising the liquid helium level). A number of diagnostic studies of the short have been made, using 1) an array of flux sensing loops to sense the magnetic effect of the short, 2) voltage comparisons between upper and lower sections of the coil, 3) comparisons of forces in the nine member coil support system and 4) the effect of the short on the thermal charactersitics of the coil. Insulation failure or a metal chip shorting out turns have been explored in some detail but a convincing determination of the exact cause of the short may never be available, (even the extreme step of unwinding the coil having a significant probability that an imperfection with the observed characteristics would pass unnoticed). Analysis of the characteristics of the short indicated that the most serious consequence would be failure of the coils mechanical support system in the event that the magnet was quickly discharged, as in a dump or quench. To deal with this hazard, the support system has been modified by installing solid supports which prevent the coil from moving by an amount sufficient to damage the support system. We have also reexamined the data and calculations used in the original coil design and have made some additional measurements of the properties of the materials (yield strength, friction coefficient, Young's modulus) used in the

Coiled-coil forming peptides for the induction of silver nanoparticles

International Nuclear Information System (INIS)

Božič Abram, Sabina; Aupič, Jana; Dražić, Goran; Gradišar, Helena; Jerala, Roman

2016-01-01

Biopolymers with defined sequence patterns offer an attractive alternative for the formation of silver nanoparticle (AgNP). A set of coiled-coil dimer forming peptides was tested for their AgNP formation ability. Seventeen of those peptides mediated the formation of AgNPs in aqueous solution at neutral pH, while the formation of a coiled-coil dimer inhibited the nanoparticle generation. A QSAR regression model on the relationship between sequence and function suggests that in this peptide type the patterns KXQQ and KXEE are favorable, whereas Ala residues appear to have an inhibitory effect. UV–VIS spectra of the obtained nanoparticles gave a peak at around 420 nm, typical for AgNPs in the size range around 40 nm, which was confirmed by dynamic light scattering and transmission electron microscopy. Peptide-induced AgNPs exhibited good antibacterial activity, even after a 15 min contact time, while they had low toxicity to human cells at the same concentrations. These results show that our designed peptides generate AgNPs with antibacterial activity at mild conditions and might be used for antibacterial coatings. - Highlights: • 17 of the 30 tested coiled-coil forming peptides induce AgNP formation. • Coiled-coil dimer formation suppresses AgNP generation of individual peptides. • Size of the peptide-induced silver nanoparticles is around 40 nm. • QSAR analysis points to the importance of KXQQ and KXEE motifs for AgNP generation. • Peptide-induced silver nanoparticles exhibit antibacterial activity.

Coiled-coil forming peptides for the induction of silver nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Božič Abram, Sabina [Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia); Graduate School of Biomedicine, University of Ljubljana, Ljubljana 1000 (Slovenia); Aupič, Jana [Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia); Doctoral Programme in Chemical Sciences, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana 1000 (Slovenia); Dražić, Goran [Laboratory for Materials Chemistry, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia); Gradišar, Helena [Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia); EN-FIST, Centre of Excellence, Trg Osvobodilne fronte 13, Ljubljana 1000 (Slovenia); Jerala, Roman, E-mail: roman.jerala@ki.si [Department of Synthetic Biology and Immunology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana (Slovenia); EN-FIST, Centre of Excellence, Trg Osvobodilne fronte 13, Ljubljana 1000 (Slovenia)

2016-04-08

Biopolymers with defined sequence patterns offer an attractive alternative for the formation of silver nanoparticle (AgNP). A set of coiled-coil dimer forming peptides was tested for their AgNP formation ability. Seventeen of those peptides mediated the formation of AgNPs in aqueous solution at neutral pH, while the formation of a coiled-coil dimer inhibited the nanoparticle generation. A QSAR regression model on the relationship between sequence and function suggests that in this peptide type the patterns KXQQ and KXEE are favorable, whereas Ala residues appear to have an inhibitory effect. UV–VIS spectra of the obtained nanoparticles gave a peak at around 420 nm, typical for AgNPs in the size range around 40 nm, which was confirmed by dynamic light scattering and transmission electron microscopy. Peptide-induced AgNPs exhibited good antibacterial activity, even after a 15 min contact time, while they had low toxicity to human cells at the same concentrations. These results show that our designed peptides generate AgNPs with antibacterial activity at mild conditions and might be used for antibacterial coatings. - Highlights: • 17 of the 30 tested coiled-coil forming peptides induce AgNP formation. • Coiled-coil dimer formation suppresses AgNP generation of individual peptides. • Size of the peptide-induced silver nanoparticles is around 40 nm. • QSAR analysis points to the importance of KXQQ and KXEE motifs for AgNP generation. • Peptide-induced silver nanoparticles exhibit antibacterial activity.

Manufacturing development of the Westinghouse Nb3Sn coil for the Large Coil Test Program

International Nuclear Information System (INIS)

Young, J.L.; Vota, T.L.; Singh, S.K.

1983-01-01

The Westinghouse Nb 3 Sn Magnet for the Oak Ridge National Laboratory Large Coil Program (LCP) is currently well into the manufacturing phase. This paper identifies the manufacturing processes and development tasks for his unique, advanced coil

Measurement of heating coil temperature for e-cigarettes with a "top-coil" clearomizer.

Science.gov (United States)

Chen, Wenhao; Wang, Ping; Ito, Kazuhide; Fowles, Jeff; Shusterman, Dennis; Jaques, Peter A; Kumagai, Kazukiyo

2018-01-01

To determine the effect of applied power settings, coil wetness conditions, and e-liquid compositions on the coil heating temperature for e-cigarettes with a "top-coil" clearomizer, and to make associations of coil conditions with emission of toxic carbonyl compounds by combining results herein with the literature. The coil temperature of a second generation e-cigarette was measured at various applied power levels, coil conditions, and e-liquid compositions, including (1) measurements by thermocouple at three e-liquid fill levels (dry, wet-through-wick, and full-wet), three coil resistances (low, standard, and high), and four voltage settings (3-6 V) for multiple coils using propylene glycol (PG) as a test liquid; (2) measurements by thermocouple at additional degrees of coil wetness for a high resistance coil using PG; and (3) measurements by both thermocouple and infrared (IR) camera for high resistance coils using PG alone and a 1:1 (wt/wt) mixture of PG and glycerol (PG/GL). For single point thermocouple measurements with PG, coil temperatures ranged from 322 ‒ 1008°C, 145 ‒ 334°C, and 110 ‒ 185°C under dry, wet-through-wick, and full-wet conditions, respectively, for the total of 13 replaceable coil heads. For conditions measured with both a thermocouple and an IR camera, all thermocouple measurements were between the minimum and maximum across-coil IR camera measurements and equal to 74% ‒ 115% of the across-coil mean, depending on test conditions. The IR camera showed details of the non-uniform temperature distribution across heating coils. The large temperature variations under wet-through-wick conditions may explain the large variations in formaldehyde formation rate reported in the literature for such "top-coil" clearomizers. This study established a simple and straight-forward protocol to systematically measure e-cigarette coil heating temperature under dry, wet-through-wick, and full-wet conditions. In addition to applied power, the

Embolization Coils Migrating and Being Passed per Rectum After Embolization of a Splenic Artery Pseudoaneurysm, 'The Migrating Coil': A Case Report

International Nuclear Information System (INIS)

Shah, Numan A.; Akingboye, Akinfemi; Haldipur, Nandon; Mackinlay, James Y.; Jacob, George

2007-01-01

Acute or chronic blood loss from pseudoaneurysms of the splanchnic artery in chronic pancreatitis poses diagnostic and management challenges. Arteriographic examination offers both diagnostic and therapeutic options, with success rates of 76%-100% for both modalities. In cases of failure of embolization, repeat embolization is also an option. Surgical intervention is advocated for rebleeding and failure of embolization. Evidence-based guidelines regarding the optimal treatment modality for this condition are lacking. There has been a reported case of dislodgement of coil into the stomach through a gastropseudocystic fistula. We report the case of a migrating steel-wire coil through the gastrointestinal tract and splenic artery pseudoaneurysm. We highlight the potential complications of pseudoaneurysm and other available therapeutic management options

Triplets pass their pressure test

CERN Multimedia

2007-01-01

All the LHC inner triplets have now been repaired and are in position. The first ones have passed their pressure tests with flying colours. The repaired inner triplet at LHC Point 1, right side (1R). Ranko Ostojic (on the right), who headed the team responsible for repairing the triplets, shows the magnet to Robert Zimmer, President of the University of Chicago and of Fermi Research Alliance, who visited CERN on 20th August.Three cheers for the triplets! All the LHC inner triplets have now been repaired and are in position in the tunnel. Thanks to the mobilisation of a multidisciplinary team from CERN and Fermilab, assisted by the KEK Laboratory and the Lawrence Berkeley National Laboratory (LBNL), a solution has been found, tested, validated and applied. At the end of March this year, one of the inner triplets at Point 5 failed to withstand a pressure test. A fault was identified in the supports of two out of the three quadruple magne...

Analytical Model of Coil Spring Damper Based on the Loading Test

Energy Technology Data Exchange (ETDEWEB)

Cho, Sung Gook; Park, Woong Ki [INNOSE TECH Co. LTD, Incheon (Korea, Republic of); Furuya, Osamu [Tokyo City University, Tokyo (Japan); Kurabayashi, Hiroshi [Vibro-System, Tokyo (Japan)

2016-05-15

The one way of solving such problems is to enhance and to develop an improved damping element used in base-isolation and response control system. A cost reduction of damper for a large scale structure is another important task to upgrade the total response control abilities in the near future. This study has examined a response control device using elastoplastic hysteresis damping of metal material. The proposed damper is designed to be coil spring element shape for a uniform stress of metal and for a reduction of low cyclic fatigue in large deformation to upgrade a repetitive strength during the earthquake motions. By using the metal material of SS400 general structural rolled steel, the corresponding cost issues of the damping element will be effectively reduced. The analytical of elasto-plastic coil spring damper (CSD) is introduced, and basic mechanical properties evaluated experimentally and analytically. This study has been examined the response control damper using elasto-plastic hysteresis characteristics of metal material. The paper described the design method of elasto-plastic coil spring damper, basic mechanical properties evaluated from loading test, and analytical model of damper are summarized. It was confirmed that the damping force and mechanical characteristics of elasto-plastic coil spring damper are almost satisfied the design specifications.

Routine phasing of coiled-coil protein crystal structures with AMPLE

Directory of Open Access Journals (Sweden)

Jens M. H. Thomas

2015-03-01

Full Text Available Coiled-coil protein folds are among the most abundant in nature. These folds consist of long wound α-helices and are architecturally simple, but paradoxically their crystallographic structures are notoriously difficult to solve with molecular-replacement techniques. The program AMPLE can solve crystal structures by molecular replacement using ab initio search models in the absence of an existent homologous protein structure. AMPLE has been benchmarked on a large and diverse test set of coiled-coil crystal structures and has been found to solve 80% of all cases. Successes included structures with chain lengths of up to 253 residues and resolutions down to 2.9 Å, considerably extending the limits on size and resolution that are typically tractable by ab initio methodologies. The structures of two macromolecular complexes, one including DNA, were also successfully solved using their coiled-coil components. It is demonstrated that both the ab initio modelling and the use of ensemble search models contribute to the success of AMPLE by comparison with phasing attempts using single structures or ideal polyalanine helices. These successes suggest that molecular replacement with AMPLE should be the method of choice for the crystallographic elucidation of a coiled-coil structure. Furthermore, AMPLE may be able to exploit the presence of a coiled coil in a complex to provide a convenient route for phasing.

Comparison of the association of sac growth and coil compaction with recurrence in coil embolized cerebral aneurysms.

Directory of Open Access Journals (Sweden)

Anna L Hoppe

Full Text Available In recurrent cerebral aneurysms treated by coil embolization, coil compaction is regarded as the presumptive mechanism. We test the hypothesis that aneurysm growth is the primary recurrence mechanism. We also test the hypothesis that the coil mass will translate a measurable extent when recurrence occurs.An objective, quantitative image analysis protocol was developed to determine the volumes of aneurysms and coil masses during initial and follow-up visits from 3D rotational angiograms. The population consisted of 15 recurrence and 12 non-recurrence control aneurysms initially completely coiled at a single center. An investigator sensitivity study was performed to assess the objectivity of the methods. Paired Wilcoxon tests (p<0.05, one-tailed were performed to assess for aneurysm and coil growth. The translation of the coil mass center at follow-up was computed. A Mann Whitney U-Test (p<0.05, one-tailed was used to compare translation of coil mass centers between recurrence and control subjects.Image analysis protocol was found to be insensitive to the investigator. Aneurysm growth was evident in the recurrence cohort (p=0.003 but not the control (p=0.136. There was no evidence of coil compaction in either the recurrence or control cohorts (recurrence: p=0.339; control: p=0.429. The translation of the coil mass centers was found to be significantly larger in the recurrence cohort than the control cohort (p=0.047.Aneurysm sac growth, not coil compaction, was the primary mechanism of recurrence following successful coil embolization. The coil mass likely translates to a measurable extent when recurrence occurs and has the potential to serve as a non-angiographic recurrence marker.

Stress relaxation in SSC 50mm dipole coils

International Nuclear Information System (INIS)

Rogers, D.; Markley, F.

1992-04-01

We are measuring the stress relaxation of SSC 50mm outer coils with the goal of predicting how much of the coil prestress will be lost while the coils are warehoused between manufacture and cooldown. We manufacture 3 inch (76.2mm) long segments of coil with the same materials and techniques that have been used for prototype coils. We are running four simultaneous tests in an attempt to separate the contributions of the different coil materials. Test one is a completely insulated coil section where the insulation is the all polyamide system being tested at Brookhaven; test two is a wire stack insulated only with the normal Kapton overwrap; test three is a stack of bare cable; and test four is a completely insulated normal coil section. All, except for the bare cable, include the ground insulation. The insulated coil sections are carefully dried before loading and testing in order to eliminate stress changes due to varying moisture content. The temperature dependence of the stress relaxation is being studied separately. Three companion papers presented at this conference will be: (1) ''Temperature dependence of the viscoelastic properties of SSC coil insulation'' (2) ''Measurement of the elastic modulus of Kapton perpendicular to the plane of the film at room and cryogenic temperatures'' (3) ''Theoretical methods for creep and stress relaxation studies of SSC coil.''

Large Coil Program magnetic system design study

International Nuclear Information System (INIS)

Moses, S.D.; Johnson, N.E.

1977-01-01

The primary objective of the Large Coil Program (LCP) is to demonstrate the reliable operation of large superconducting coils to provide a basis for the design principles, materials, and fabrication techniques proposed for the toroidal magnets for the THE NEXT STEP (TNS) and other future tokamak devices. This paper documents a design study of the Large Coil Test Facility (LCTF) in which the structural response of the Toroidal Field (TF) Coils and the supporting structure was evaluated under simulated reactor conditions. The LCP test facility structural system consists of six TF Coils, twelve coil-to-coil torsional restraining beams (torque rings), a central bucking post with base, and a Pulse Coil system. The NASTRAN Finite Element Structural Analysis computer Code was utilized to determine the distribution of deflections, forces, and stresses for each of the TF Coils, torque rings, and the central bucking post. Eleven load conditions were selected to represent probable test operations. Pulse Coils suspended in the bore of the test coil were energized to simulate the pulsed field environment characteristic of the TNS reactor system. The TORMAC Computer Code was utilized to develop the magnetic forces in the TF Coils for each of the eleven loading conditions examined, with or without the Pulse Coils energized. The TORMAC computer program output forces were used directly as input load conditions for the NASTRAN analyses. Results are presented which demonstrate the reliability of the LCTF under simulated reactor operating conditions

Manufacturing and preliminary tests of a 12 T ''wind and react'' coil

International Nuclear Information System (INIS)

Corte, A. della; Pasotti, G.; Sacchetti, N.; Spadoni, M.; Oliva, A.B.; Penco, R.; Parodi, S.; Valle, N.; Specking, W.

1994-01-01

As already reported ENEA is engaged in the realization of a 12 T wind and react Nb 3 Sn coil, a subsize magnet designed to simulate many technological problems to be faced in NET-ITER magnets. EM-LMI and Ansaldo are the industrial partners in this project. A preliminary winding has been built and successfully tested. This winding has been cut in pieces and carefully inspected to be sure that the impregnation process after the heat treatment works well. No particular flaws have been detected. Then manufacturing of the 12 T magnet has been started and completed in about three months. Heat treatment, impregnation and electrical tests at 300 K have been successfully performed and the magnet is now ready for final tests. In order to obtain the most significant scientific and technological information from this magnet, the original test program (insertion of the coil in the SULTAN facility) has been modified according to a decision of the Fusion Technology Steering Committee (FTSC) of EURATOM. Details of the new test programs are given in the paper

Recent progress and tests of radiation resistant impregnation materials for Nb3Sn coils

International Nuclear Information System (INIS)

Bossert, R.; Krave, S.; Ambrosio, G.; Andreev, N.; Chlachidze, G.; Nobrega, A.; Novitski, I.; Yu, M.; Zlobin, A. V.

2014-01-01

Fermilab is collaborating with Lawrence Berkeley National Laboratory (LBNL) and Brookhaven National Laboratory (BNL) (US-LARP collaboration) to develop a large-aperture Nb 3 Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade. An important component of this work is the development of materials that are sufficiently radiation resistant for use in critical areas of the upgrade. This paper describes recent progress in characterization of materials, including the baseline CTD101K epoxy, cyanate ester blends, and Matrimid 5292, a bismaleimide-based system. Structural properties of “ten stacks” of cable impregnated with these materials are tested at room and cryogenic temperatures and compared to the baseline CT-101K. Experience with potting 1 and 2 meter long coils with Matrimid 5292 are described. Test results of a single 1-m coil impregnated with Matrimid 5292 are reported and compared to similar coils impregnated with the traditional epoxy

Recent progress and tests of radiation resistant impregnation materials for Nb3Sn coils

Science.gov (United States)

Bossert, R.; Krave, S.; Ambrosio, G.; Andreev, N.; Chlachidze, G.; Nobrega, A.; Novitski, I.; Yu, M.; Zlobin, A. V.

2014-01-01

Fermilab is collaborating with Lawrence Berkeley National Laboratory (LBNL) and Brookhaven National Laboratory (BNL) (US-LARP collaboration) to develop a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade. An important component of this work is the development of materials that are sufficiently radiation resistant for use in critical areas of the upgrade. This paper describes recent progress in characterization of materials, including the baseline CTD101K epoxy, cyanate ester blends, and Matrimid 5292, a bismaleimide-based system. Structural properties of "ten stacks" of cable impregnated with these materials are tested at room and cryogenic temperatures and compared to the baseline CT-101K. Experience with potting 1 and 2 meter long coils with Matrimid 5292 are described. Test results of a single 1-m coil impregnated with Matrimid 5292 are reported and compared to similar coils impregnated with the traditional epoxy.

Magnetic Test Facility - Sensor and Coil Calibrations

Science.gov (United States)

2013-08-01

amplitude of signals induced into the sensor. 2.1.1.2 Fluxgate magnetometers Fluxgate sensors consist of a ferromagnetic core, around which drive and sense...kHz range to be measured. Fluxgate magnetometers do not have a lower limit to their fre- quency response, and hence can be used to measure...placed within a larger triaxial coil which is used in conjunction with a fluxgate magnetometer to cancel earth’s field at the cen- tre of the coil. A

Mechanical testing and development of the helical field coil joint for the Advanced Toroidal Facility

International Nuclear Information System (INIS)

Nelson, B.E.; Bryan, W.E.; Goranson, P.L.; Warwick, J.E.

1985-01-01

The helical field (HF) coil set for the Advanced Toroidal Facility (ATF) is an M = 12, l = 2, constant-ratio torsatron winding consisting of 2 coils, each with 14 turns of heavy copper conductor. The coils are divided into 24 identical segments to facilitate fabrication and minimize the assembly schedule. The segments are connected across through-bolted lap joints that must carry up to 124,000 A per turn for 5 s or 62,500 A steady-state. In addition, the joints must carry the high magnetic and thermal loads induced in the conductor and still fit within the basic 140- by 30-mm copper envelope. Extensive testing and development were undertaken to verify and refine the basic joint design. Tests included assembly force and clamping force for various types of misalignment; joint resistance as a function of clamping force; clamp bolt relaxation due to thermal cycling; fatigue testing of full-size, multiturn joint prototypes; and low-cycle fatigue and tensile tests of annealed CDA102 copper. The required performance parameters and actual test results, as well as the final joint configuration, are presented. 2 refs., 9 figs., 4 tabs

46 CFR 64.83 - Hydrostatic test.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Hydrostatic test. 64.83 Section 64.83 Shipping COAST... HANDLING SYSTEMS Periodic Inspections and Tests of MPTs § 64.83 Hydrostatic test. (a) The hydrostatic test..., the heating coil passing a hydrostatic test at a pressure of 200 psig or more or 50 percent or more...

Progress on large superconducting toroidal field coils

International Nuclear Information System (INIS)

Haubenreich, P.N.; Luton, J.N.; Thompson, P.B.; Beard, D.S.

1979-01-01

Large superconducting toroidal field coils of competing designs are being produced by six major industrial teams. In the US, teams headed by General Dynamics Convair, General Electric, and Westinghouse are under contract to design and fabricate one coil each to specifications established by the Large Coil Program. A facility for testing 6 coils in a toroidal array at fields to 8 to 12 tesla is under construction at Oak Ridge. Through an international agreement, EURATOM, Japan, and Switzerland will produce one coil each for testing with the US coils. Each test coil will have a 2.5 x 3.5 m D-shape winding bore and is designed to operate at a current of 10 to 18 kA at a peak field of 8T while subjected to pulsed fields of 0.14 T applied in 1.0 s. There are significant differences among the six coil designs: five use NbTi, one Nb 3 Sn; three are cooled by pool boiling helium, three by forced flow; five have welded or bolted stainless steel coil cases, one has aluminum plate structure. All are designed to be cryostable at 8T, with structural margin for extended operation. The three US coil teams are almost or completely finished with detailed design and are now procuring materials and setting up manufacturing equipment. The non-US teams are at various stages of verification testing and design. The GDC and GE coils are scheduled for delivery in the spring of 1981 and the others will be completed a year later. The 11-m diameter vessel at the test facility has been completed and major components of the test stand are being procured. Engineering and procurement to upgrade the helium liquifier-refrigerator system are under way

Using GIFTS on the Cray-1 for the large coil test facility test: stand design analysis

International Nuclear Information System (INIS)

Baudry, T.V.; Gray, W.H.

1981-06-01

The GIFTS finite element program has been used extensively throughout the Large Coil Test Facility (LCTF) test stand design analysis. Effective use has been made of GIFTS both as a preprocessor to other finite element programs and as a complete structural analysis package. The LCTF test stand design involved stress analysis ranging from simple textbook-type problems to very complicated three-dimensional structural problems. Two areas of the design analysis are discussed

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

International Nuclear Information System (INIS)

Oomen, Marijn; Herkert, Werner; Bayer, Dietmar; Kummeth, Peter; Nick, Wolfgang; Arndt, Tabea

2012-01-01

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

Super-low-frequency wireless power transfer with lightweight coils for passing through a stainless steel plate

Science.gov (United States)

Ishida, Hiroki; Kyoden, Tomoaki; Furukawa, Hiroto

2018-03-01

To achieve wireless power transfer (WPT) through a stainless-steel plate, a super-low frequency (SLF) was used as a resonance frequency. In our previous study of SLF-WPT, heavy coils were prepared. In this study, we designed lightweight coils using a WPT simulator that we developed previously. As a result, the weight was reduced to 1.69 kg from 11.9 kg, the previous coil weight. At a resonance frequency of 400 Hz, the transmission efficiency and output power of advanced SLF-WPT reached 91% and 426 W, respectively, over a transmission distance of 30 mm. Furthermore, 80% efficiency and 317 W output were achieved when transmitting power through a 1 mm-thick stainless-steel plate. This performance is much better than that in previous reports. We show using both calculations and experimental results that a power-to-weight ratio of 252 W/kg is possible even when using a 400 Hz power supply frequency.

Evidence-based pathology: umbilical cord coiling.

Science.gov (United States)

Khong, T Y

2010-12-01

The generation of a pathology test result must be based on criteria that are proven to be acceptably reproducible and clinically relevant to be evidence-based. This review de-constructs the umbilical cord coiling index to illustrate how it can stray from being evidence-based. Publications related to umbilical cord coiling were retrieved and analysed with regard to how the umbilical coiling index was calculated, abnormal coiling was defined and reference ranges were constructed. Errors and other influences that can occur with the measurement of the length of the umbilical cord or of the number of coils can compromise the generation of the coiling index. Definitions of abnormal coiling are not consistent in the literature. Reference ranges defining hypocoiling or hypercoiling have not taken those potential errors or the possible effect of gestational age into account. Even the way numerical test results in anatomical pathology are generated, as illustrated by the umbilical coiling index, warrants a critical analysis into its evidence base to ensure that they are reproducible or free from errors.

Passing the Turing Test Does Not Mean the End of Humanity.

Science.gov (United States)

Warwick, Kevin; Shah, Huma

In this paper we look at the phenomenon that is the Turing test. We consider how Turing originally introduced his imitation game and discuss what this means in a practical scenario. Due to its popular appeal we also look into different representations of the test as indicated by numerous reviewers. The main emphasis here, however, is to consider what it actually means for a machine to pass the Turing test and what importance this has, if any. In particular does it mean that, as Turing put it, a machine can "think". Specifically we consider claims that passing the Turing test means that machines will have achieved human-like intelligence and as a consequence the singularity will be upon us in the blink of an eye.

TFTR D and D Project: Final Examination and Testing of the TFTR TF-Coils

International Nuclear Information System (INIS)

Zatz, Irving J.

2003-01-01

In operation for nearly 15 years, TFTR (Tokamak Fusion Test Reactor) was not only a fusion science milestone, but a milestone of achievement in engineering as well. The TFTR DandD (Decommissioning and Decontamination) program provided a rare opportunity to examine machine components that had been exposed to a unique performance environment of greater than 100,000 mechanical and thermal load cycles. In particular, the possible examination of the TFTR toroidal-field (TF) coils, which met, then exceeded, the 5.2 Tesla magnetic field machine specification, could supply the answers to many questions that have been asked and debated since the coils were originally designed and built. A test program conducted in parallel with the DandD effort was the chance to look inside and examine, in detail, the TFTR TF coils for the first time since they were delivered encased to PPPL (Princeton Plasma Physics Laboratory). The results from such a program would provide data and insight that would not only be nefit PPPL and the fusion community, but the broader scientific community as well

Pulse coil concepts for the LCP Facility

International Nuclear Information System (INIS)

Nelson, B.E.; Burn, P.B.

1977-01-01

The pulse coils described in this paper are resistive copper magnets driven by time-varying currents. They are included in the Large Coil Test Facility (LCTF) portion of the Large Coil Program (LCP) to simulate the pulsed field environment of the toroidal coils in a tokamak reactor. Since TNS (a 150 sec, 5MA, igniting tokamak) and the Oak Ridge EPR (Experimental Power Reactor) are representative of the first tokamaks to require the technology developed in LCP, the reference designs for these machines, especially TNS, are used to derive the magnetic criteria for the pulse coils. This criteria includes the magnitude, distribution, and rate of change of pulsed fields in the toroidal coil windings. Three pulse coil concepts are evaluated on the basis of magnetic criteria and factors such as versatility of design, ease of fabrication and cost of operation. The three concepts include (1) a pair of poloidal coils outside the LCTF torus, (2) a single poloidal coil threaded through the torus, and (3) a pair of vertical axis coil windings inside the bore of one or more of the toroidal test coils

Optimization of the ECT background coil

International Nuclear Information System (INIS)

Ballou, J.K.; Luton, J.N.

1975-01-01

This study was begun to optimize the Eccentric Coil Test (ECT) background coil. In the course of this work a general optimization code was obtained, tested, and applied to the ECT problem. So far this code has proven to be very satisfactory. The results obtained with this code and earlier codes have illustrated the parametric behavior of such a coil system and that the optimum for this type system is broad. This study also shows that a background coil with a winding current density of less than 3000 A/cm 2 is not feasible for the ECT models presented in this paper

Design and use of a folded four-ring double-tuned birdcage coil for rat brain sodium imaging at 9.4 T

Science.gov (United States)

Ha, YongHyun; Choi, Chang-Hoon; Worthoff, Wieland A.; Shymanskaya, Aliaksandra; Schöneck, Michael; Willuweit, Antje; Felder, Jörg; Shah, N. Jon

2018-01-01

A folded four-ring quadrature birdcage coil was designed and constructed with a double-tune configuration of an outer high-pass coil for 1H (400 MHz) and inner low-pass coil for 23Na (105.72 MHz at 9.4 T). The coil was evaluated on the bench and in the scanner, comparing its performance with that of single-tuned coils and a large four-ring coil. All coils were tuned and matched and the isolation between two quadrature ports was found to be better than -13.7 dB for 1H and -27 dB for 23Na. Signal-to-noise ratios (SNRs) were calculated and 23Na flip angle maps were acquired. 23Na SNR of the folded four-ring reached ∼93% of that obtained with the single-tuned coil. A set of in vivo1H and 23Na axial images to cover the whole rat brain were obtained. The performance of the folded four-ring coil and its benefit for 23Na imaging experiments have been demonstrated. This proposed four-ring coil could avoid length restrictions, e.g. the shoulders, by folding the outer rings vertically. This facilitates the construction of double-tuned four-ring birdcage coils just to fit the head, leading to higher filling factors and better SNR.

Fine-tuning of protein domain boundary by minimizing potential coiled coil regions

International Nuclear Information System (INIS)

Iwaya, Naoko; Goda, Natsuko; Unzai, Satoru; Fujiwara, Kenichiro; Tanaka, Toshiki; Tomii, Kentaro; Tochio, Hidehito; Shirakawa, Masahiro; Hiroaki, Hidekazu

2007-01-01

Structural determination of individual protein domains isolated from multidomain proteins is a common approach in the post-genomic era. Novel and thus uncharacterized domains liberated from intact proteins often self-associate due to incorrectly defined domain boundaries. Self-association results in missing signals, poor signal dispersion and a low signal-to-noise ratio in 1 H- 15 N HSQC spectra. We have found that a putative, non-canonical coiled coil region close to a domain boundary can cause transient hydrophobic self-association and monomer-dimer equilibrium in solution. Here we propose a rational method to predict putative coiled coil regions adjacent to the globular core domain using the program COILS. Except for the amino acid sequence, no preexisting knowledge concerning the domain is required. A small number of mutant proteins with a minimized coiled coil region have been rationally designed and tested. The engineered domains exhibit decreased self-association as assessed by 1 H- 15 N HSQC spectra with improved peak dispersion and sharper cross peaks. Two successful examples of isolating novel N-terminal domains from AAA-ATPases are demonstrated. Our method is useful for the experimental determination of domain boundaries suited for structural genomics studies

Fine-tuning of protein domain boundary by minimizing potential coiled coil regions.

Science.gov (United States)

Iwaya, Naoko; Goda, Natsuko; Unzai, Satoru; Fujiwara, Kenichiro; Tanaka, Toshiki; Tomii, Kentaro; Tochio, Hidehito; Shirakawa, Masahiro; Hiroaki, Hidekazu

2007-01-01

Structural determination of individual protein domains isolated from multidomain proteins is a common approach in the post-genomic era. Novel and thus uncharacterized domains liberated from intact proteins often self-associate due to incorrectly defined domain boundaries. Self-association results in missing signals, poor signal dispersion and a low signal-to-noise ratio in (1)H-(15)N HSQC spectra. We have found that a putative, non-canonical coiled coil region close to a domain boundary can cause transient hydrophobic self-association and monomer-dimer equilibrium in solution. Here we propose a rational method to predict putative coiled coil regions adjacent to the globular core domain using the program COILS. Except for the amino acid sequence, no preexisting knowledge concerning the domain is required. A small number of mutant proteins with a minimized coiled coil region have been rationally designed and tested. The engineered domains exhibit decreased self-association as assessed by (1)H-(15)N HSQC spectra with improved peak dispersion and sharper cross peaks. Two successful examples of isolating novel N-terminal domains from AAA-ATPases are demonstrated. Our method is useful for the experimental determination of domain boundaries suited for structural genomics studies.

Large superconducting coil fabrication development

International Nuclear Information System (INIS)

Brown, R.L.; Allred, E.L.; Anderson, W.C.; Burn, P.B.; Deaderick, R.I.; Henderson, G.M.; Marguerat, E.F.

1975-01-01

Toroidal fields for some fusion devices will be produced by an array of large superconducting coils. Their size, space limitation, and field requirements dictate that they be high performance coils. Once installed, accessibility for maintenance and repairs is severely restricted; therefore, good reliability is an obvious necessity. Sufficient coil fabrication will be undertaken to develop and test methods that are reliable, fast, and economical. Industrial participation will be encouraged from the outset to insure smooth transition from development phases to production phases. Initially, practice equipment for three meter bore circular coils will be developed. Oval shape coil forms will be included in the practice facility later. Equipment that is more automated will be developed with the expectation of winding faster and obtaining good coil quality. Alternate types of coil construction, methods of winding and insulating, will be investigated. Handling and assembly problems will be studied. All technology developed must be feasible for scaling up when much larger coils are needed. Experimental power reactors may need coils having six meter or larger bores

Selection and application of C18200 chrome copper for the OHTE confinement test helical coil

International Nuclear Information System (INIS)

Puhn, F.A.; Graumann, D.W.

1981-01-01

The selection and qualification of copper for the OHTE confinement test helical coil (H-coil) was a crucial step in the success of this new experiment. Previous problems encountered at General Atomic Company with close tolerance machined parts made from high strength copper were identified. The design criteria included selecting a material with minimal warpage during machining, an electrical conductivity >80% IACS, and a yield strength of at least 241 Mpa (35 ksi). The investigation of candidate materials and testing samples led to selection of a material that fully met all requirements. The C18200 chrome copper forged plates were supplied by the Ampco Metal Division of Ampco-Pittsburgh Corporation

Using magnetic coils to produce periodically applied forces to maintain the high speed movement of bodies and vehicles, particularly in tubes evacuated of air

International Nuclear Information System (INIS)

Pedrick, A.P.

1976-01-01

An arrangement is described in which a body is accelerated or maintained in motion along a track that passes through a number of annular electromagnet coils, the length of the body being substantially less than the distance between two adjacent coils. A series if electronmagnetically produced force pulses is applied to the body as it passes through successive coils, by the use of an automatic switch operated by the body. Control is provided so that each coil is de-energized at or before maximum magnetic flux linkage is attained between coil and body, the arrangement being such that the body is accelerated into the coil, but leaves it at a much reduced flux linkage. The possible uses of such an arrangement are mentioned: these include the acceleration of bullets, incorporating D and T in pellet form in their concave noses, to obtain a nuclear fusion reaction. (U.K.)

Quench detector for large pulsed coils and quench analysis for the LASL/Westinghouse 20 MJ coil

International Nuclear Information System (INIS)

Hennessy, M.J.; Heintz, A.W.; Eckels, P.W.

1981-01-01

A detection scheme has been devised for use in the test of the 20 Mj Induction Heating Coil. This scheme allows the sensing of plus or minus voltages less than 320 mv resistive in magnitude in coils which will have inductive voltage components as high as /plus or minus/2.5 kv. The network which achieves this sensitivity is stable to less than 12.8 ppm. This method adopted involves the bucking out of the inductive voltage with two secondary co-wound flux sensing coils tapped at locations adjacent to voltage taps in the main superconducting coil. The detection scheme is recommended if large ripple or control voltages exist subsequent to the coil pulse. The most severe event which might quench the coil and/or damage the winding is exposure of the coil to gaseous cooling through lack of proper liquid level control. The detection scheme will protect the coil against this and other abnormal conditions that could damage the coil

Molecular basis of coiled-coil oligomerization-state specificity.

Science.gov (United States)

Ciani, Barbara; Bjelic, Saša; Honnappa, Srinivas; Jawhari, Hatim; Jaussi, Rolf; Payapilly, Aishwarya; Jowitt, Thomas; Steinmetz, Michel O; Kammerer, Richard A

2010-11-16

Coiled coils are extensively and successfully used nowadays to rationally design multistranded structures for applications, including basic research, biotechnology, nanotechnology, materials science, and medicine. The wide range of applications as well as the important functions these structures play in almost all biological processes highlight the need for a detailed understanding of the factors that control coiled-coil folding and oligomerization. Here, we address the important and unresolved question why the presence of particular oligomerization-state determinants within a coiled coil does frequently not correlate with its topology. We found an unexpected, general link between coiled-coil oligomerization-state specificity and trigger sequences, elements that are indispensable for coiled-coil formation. By using the archetype coiled-coil domain of the yeast transcriptional activator GCN4 as a model system, we show that well-established trimer-specific oligomerization-state determinants switch the peptide's topology from a dimer to a trimer only when inserted into the trigger sequence. We successfully confirmed our results in two other, unrelated coiled-coil dimers, ATF1 and cortexillin-1. We furthermore show that multiple topology determinants can coexist in the same trigger sequence, revealing a delicate balance of the resulting oligomerization state by position-dependent forces. Our experimental results should significantly improve the prediction of the oligomerization state of coiled coils. They therefore should have major implications for the rational design of coiled coils and consequently many applications using these popular oligomerization domains.

Design and use of a folded four-ring double-tuned birdcage coil for rat brain sodium imaging at 9.4 T.

Science.gov (United States)

Ha, YongHyun; Choi, Chang-Hoon; Worthoff, Wieland A; Shymanskaya, Aliaksandra; Schöneck, Michael; Willuweit, Antje; Felder, Jörg; Shah, N Jon

2018-01-01

A folded four-ring quadrature birdcage coil was designed and constructed with a double-tune configuration of an outer high-pass coil for 1 H (400 MHz) and inner low-pass coil for 23 Na (105.72 MHz at 9.4 T). The coil was evaluated on the bench and in the scanner, comparing its performance with that of single-tuned coils and a large four-ring coil. All coils were tuned and matched and the isolation between two quadrature ports was found to be better than -13.7 dB for 1 H and -27 dB for 23 Na. Signal-to-noise ratios (SNRs) were calculated and 23 Na flip angle maps were acquired. 23 Na SNR of the folded four-ring reached ∼93% of that obtained with the single-tuned coil. A set of in vivo 1 H and 23 Na axial images to cover the whole rat brain were obtained. The performance of the folded four-ring coil and its benefit for 23 Na imaging experiments have been demonstrated. This proposed four-ring coil could avoid length restrictions, e.g. the shoulders, by folding the outer rings vertically. This facilitates the construction of double-tuned four-ring birdcage coils just to fit the head, leading to higher filling factors and better SNR. Copyright © 2017 Elsevier Inc. All rights reserved.

Active internal corrector coils

International Nuclear Information System (INIS)

Thompson, P.A.; Cottingham, J.; Dahl, P.

1986-01-01

Trim or corrector coils to correct main magnet field errors and provide higher multipole fields for beam optics purposes are a standard feature of superconducting magnet accelerator systems. This paper describes some of the design and construction features of powered internal trim coils and a sampling of the test results obtained

Fabrication and testing of a superconducting coil: Phase 3 of the Maglev development program

Energy Technology Data Exchange (ETDEWEB)

Fife, A A; Lee, S; Tillotson, M [CTF Systems Inc., Port Coquitlam, BC (Canada)

1989-03-01

This report documents developmental research on superconducting magnet technology suitable for the levitation and propulsion units of the Canadian Maglev vehicle. The contract work involved the design, fabrication and testing of a racetrack coil fabricated using epoxy-impregnated windings of copper stabilized NbTi wire. The following results were achieved: successful fabrication and testing of a superconducting racetrack magnet with strength {gt} 400,000 A-turns integrated in a support frame; selection and characterization of cryogenic strain gauges; characterization of strain in solenoidal and racetrack superconducting magnets; design, fabrication and testing of high current persistent switches; and operation of superconducting magnets in persistent mode. The racetrack coil reached the design current after the third quench and short sample critical current after the eighth quench. This behavior is essentially identical to that observed with a superconducting solenoid fabricated during a previous phase. The strain measured perpendicular to the straight sides of the racetrack coil was proportional to the square of the energizing current. Persistent switches were fabricated, one type with low resistance (10{sup -2} ohm) and the other with high resistance (1.2 ohm) in their normal states. The low resistance switch could be operated in 1-Tesla fields with stabel characteristics up to about 800A drive current and the high resistance switch to 475A.

A periodic table of coiled-coil protein structures.

Science.gov (United States)

Moutevelis, Efrosini; Woolfson, Derek N

2009-01-23

Coiled coils are protein structure domains with two or more alpha-helices packed together via interlacing of side chains known as knob-into-hole packing. We analysed and classified a large set of coiled-coil structures using a combination of automated and manual methods. This led to a systematic classification that we termed a "periodic table of coiled coils," which we have made available at http://coiledcoils.chm.bris.ac.uk/ccplus/search/periodic_table. In this table, coiled-coil assemblies are arranged in columns with increasing numbers of alpha-helices and in rows of increased complexity. The table provides a framework for understanding possibilities in and limits on coiled-coil structures and a basis for future prediction, engineering and design studies.

Plea to lower English test pass marks for EEA nurses.

Science.gov (United States)

Longhurst, Chris

2017-08-09

Nurses from a group campaigning for the rights of EU citizens in the UK after Brexit are meeting the Nursing and Midwifery Council (NMC) to press for the pass mark for English language tests to be lowered.

Cable testing for Fermilab's high field magnets using small racetrack coils

International Nuclear Information System (INIS)

Feher, S.; Ambrosio, G.; Andreev, N.; Barzi, E.; Bordini, B.; Bossert, R.; Carcagno, R.; Kashikhin, V.I.; Kashikhin, V.V.; Lamm, M.J.; Novitski, I.; Orris, D.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.; Yamada, R.; Zlobin, A.V.

2004-01-01

As part of the High Field Magnet program at Fermilab simple magnets have been designed utilizing small racetrack coils based on a sound mechanical structure and bladder technique developed by LBNL. Two of these magnets have been built in order to test Nb 3 Sn cables used in cos-theta dipole models. The powder-in-tube strand based cable exhibited excellent performance. It reached its critical current limit within 14 quenches. Modified jelly roll strand based cable performance was limited by magnetic instabilities at low fields as previously tested dipole models which used similar cable

Superconducting coil development and motor demonstration: Overview

Science.gov (United States)

Gubser, D. U.

1995-12-01

Superconducting bismuth-cuprate wires, coils, and magnets are being produced by industry as part of a program to test the viability of using such magnets in Naval systems. Tests of prototype magnets, coils, and wires reveal progress in commercially produced products. The larger magnets will be installed in an existing superconducting homopolar motor and operated initially at 4.2K to test the performance. It is anticipated that approximately 400 Hp will be achieved by the motor. This article reports on the initial tests of the magnets, coils, and wires as well as the development program to improve their performance.

Multicoil2: predicting coiled coils and their oligomerization states from sequence in the twilight zone.

Directory of Open Access Journals (Sweden)

Jason Trigg

Full Text Available The alpha-helical coiled coil can adopt a variety of topologies, among the most common of which are parallel and antiparallel dimers and trimers. We present Multicoil2, an algorithm that predicts both the location and oligomerization state (two versus three helices of coiled coils in protein sequences. Multicoil2 combines the pairwise correlations of the previous Multicoil method with the flexibility of Hidden Markov Models (HMMs in a Markov Random Field (MRF. The resulting algorithm integrates sequence features, including pairwise interactions, through multinomial logistic regression to devise an optimized scoring function for distinguishing dimer, trimer and non-coiled-coil oligomerization states; this scoring function is used to produce Markov Random Field potentials that incorporate pairwise correlations localized in sequence. Multicoil2 significantly improves both coiled-coil detection and dimer versus trimer state prediction over the original Multicoil algorithm retrained on a newly-constructed database of coiled-coil sequences. The new database, comprised of 2,105 sequences containing 124,088 residues, includes reliable structural annotations based on experimental data in the literature. Notably, the enhanced performance of Multicoil2 is evident when tested in stringent leave-family-out cross-validation on the new database, reflecting expected performance on challenging new prediction targets that have minimal sequence similarity to known coiled-coil families. The Multicoil2 program and training database are available for download from http://multicoil2.csail.mit.edu.

Manufacture of EAST VS In-Vessel Coil

International Nuclear Information System (INIS)

Long, Feng; Wu, Yu; Du, Shijun; Jin, Huan; Yu, Min; Han, Qiyang; Wan, Jiansheng; Liu, Bin; Qiao, Jingchun; Liu, Xiaochuan; Li, Chang; Cai, Denggang; Tong, Yunhua

2013-01-01

Highlights: • ITER like Stainless Steel Mineral Insulation Conductor (SSMIC) used for EAST Tokamak VS In-Vessel Coil manufacture first time. • Research on SSMIC fabrication was introduced in detail. • Two sets totally four single-turn VS coils were manufactured and installed in place symmetrically above and below the mid-plane in the vacuum vessel of EAST. • The manufacture and inspection of the EAST VS coil especially the joint for the SSMIC connection was described in detail. • The insulation resistances of all the VS coils have no significant reduction after endurance test. -- Abstract: In the ongoing latest update round of EAST (Experimental Advanced Superconducting Tokamak), two sets of two single-turn Vertical Stabilization (VS) coils were manufactured and installed symmetrically above and below the mid-plane in the vacuum vessel of EAST. The Stainless Steel Mineral Insulated Conductor (SSMIC) developed for ITER In-Vessel Coils (IVCs) in Institute of Plasma Physics, Chinese Academy of Science (ASIPP) was used for the EAST VS coils manufacture. Each turn poloidal field VS coil includes three internal joints in the vacuum vessel. The middle joint connects two pieces of conductor which together form an R2.3 m arc segment inside the vacuum vessel. The other two joints connect the arc segment with the two feeders near the port along the toroidal direction to bear lower electromagnetic loads during operation. Main processes and tests include material performances checking, conductor fabrication, joint connection and testing, coil forming, insulation performances measurement were described herein

Intensity correction method customized for multi-animal abdominal MR imaging with 3 T clinical scanner and multi-array coil

International Nuclear Information System (INIS)

Mitsuda, Minoru; Yamaguchi, Masayuki; Nakagami, Ryutaro; Furuta, Toshihiro; Fujii, Hirofumi; Sekine, Norio; Niitsu, Mamoru; Moriyama, Noriyuki

2013-01-01

Simultaneous magnetic resonance (MR) imaging of multiple small animals in a single session increases throughput of preclinical imaging experiments. Such imaging using a 3-tesla clinical scanner with multi-array coil requires correction of intensity variation caused by the inhomogeneous sensitivity profile of the coil. We explored a method for correcting intensity that we customized for multi-animal MR imaging, especially abdominal imaging. Our institutional committee for animal experimentation approved the protocol. We acquired high resolution T 1 -, T 2 -, and T 2 * -weighted images and low resolution proton density-weighted images (PDWIs) of 4 rat abdomens simultaneously using a 3T clinical scanner and custom-made multi-array coil. For comparison, we also acquired T 1 -, T 2 -, and T 2 * -weighted volume coil images in the same rats in 4 separate sessions. We used software created in-house to correct intensity variation. We applied thresholding to the PDWIs to produce binary images that displayed only a signal-producing area, calculated multi-array coil sensitivity maps by dividing low-pass filtered PDWIs by low-pass filtered binary images pixel by pixel, and divided uncorrected T 1 -, T 2 -, or T 2 * -weighted images by those maps to obtain intensity-corrected images. We compared tissue contrast among the liver, spinal canal, and muscle between intensity-corrected multi-array coil images and volume coil images. Our intensity correction method performed well for all pulse sequences studied and corrected variation in original multi-array coil images without deteriorating the throughput of animal experiments. Tissue contrasts were comparable between intensity-corrected multi-array coil images and volume coil images. Our intensity correction method customized for multi-animal abdominal MR imaging using a 3T clinical scanner and dedicated multi-array coil could facilitate image interpretation. (author)

Thermal and Mechanical Performance of the First MICE Coupling Coil and the Fermilab Solenoid Test Facility

Energy Technology Data Exchange (ETDEWEB)

Rabehl, Roger [Fermilab; Carcagno, Ruben [Fermilab; Caspi, Shlomo [LBNL, Berkeley; DeMello, Allan [LBNL, Berkeley; Kokoska, Lidija [Fermilab; Orris, D. [Fermilab; Pan, Heng [LBNL, Berkeley; Sylvester, Cosmore [Fermilab; Tartaglia, Michael

2014-11-06

The first coupling coil for the Muon Ionization Cooling Experiment (MICE) has been tested in a conduction-cooled environment at the Solenoid Test Facility at Fermilab. An overview of the thermal and mechanical performance of the magnet and the test stand during cool-down and power testing of the magnet is presented.

Project status of manufacturing of European toroidal coils ITER. Validation tests

International Nuclear Information System (INIS)

Pando, F.; Felipe, A.; Madorran, A.; Pallisa, J.; Dormicch, O.; Valle, N.; D'Urzo, C.; Marin, M.; Pesenti, P.; Lucas, J.; Moreno, N.; Bonito-Oliva, A.; Harrison, R.; Bellesia, B.; Cornelis, M.; Cornella, J.

2015-01-01

The toroidal field coils are the ITER magnets responsible for confining the plasma inside the vacuum vessel. The consortium formed by IBERDROLA Ingenieria y Construccion, ASG Superconductors y ELYTT Energy is the responsible for the supply of 10 coils that the european agency F4E has to supply for the ITER project. At present, the coils are been manufactured in La Spezia (Italy), after the qualification of all the manufacturing process and the sucessfull manufacturing of a full scale prototype. (Author)

Design of the dummy coil for magnet power supply

International Nuclear Information System (INIS)

Kim, Chang-Hwan; Choi, Jae-Hoon; Jin, Jong-Kook; Lee, Dong-Keun; Kong, Jong-Dea; Joung, Nam-Young; Kim, Sang-Tae; Kim, Young-Jin; Kim, Yang-Soo; Kwon, Myeun

2013-01-01

Highlights: • It is necessary to confirm safety of the MPS on a dummy coil before the operating it. • We selected and designed the water cooling type dummy coil to test on the MPS's rating (12.5 kA) test. • For the design of the dummy coil, we considered requirements about electrical, structural and water cooling. • We will test as the rating power after MPS upgrade and that test will do before every KSTAR campaign. -- Abstract: It is necessary to test it on a dummy coil, before using a magnet power supply (MPS) to energize a Poloidal Field (PF) coil in the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The dummy coil should accept the same large current from the MPS as the PF coil and be within the capability of the utilities located at the KSTAR site. Therefore a coil design based on the characteristics of the MPS and other restrictive conditions needed to be made. There are three requirements to be met in the design: an electrical requirement, a structural requirement, and a water cooling requirement. The electrical requirement was that the coil should have an inductance of 40 mH. For the structural requirement, the material should be non magnetic. The coil support structure and water cooling manifold were made of SUS 304. The water cooling requirement was that there should be sufficient flow rate so that the temperature rise ΔT should not exceed 12 °C for operation at 12.5 kA for 5 min. Square cross-section hollow conductor with dimensions of 38.1 mm × 38.1 mm was used with a 25.4 mm center hole for cooling water. However, as a result of tests, it was found that the electrical and structural requirements were satisfied but that the water cooling was over designed. It is imperative that the verification will be redone for a test with 12.5 kA for 5 min

Design of the dummy coil for magnet power supply

Energy Technology Data Exchange (ETDEWEB)

Kim, Chang-Hwan, E-mail: kch2004@nfri.re.kr; Choi, Jae-Hoon; Jin, Jong-Kook; Lee, Dong-Keun; Kong, Jong-Dea; Joung, Nam-Young; Kim, Sang-Tae; Kim, Young-Jin; Kim, Yang-Soo; Kwon, Myeun

2013-11-15

Highlights: • It is necessary to confirm safety of the MPS on a dummy coil before the operating it. • We selected and designed the water cooling type dummy coil to test on the MPS's rating (12.5 kA) test. • For the design of the dummy coil, we considered requirements about electrical, structural and water cooling. • We will test as the rating power after MPS upgrade and that test will do before every KSTAR campaign. -- Abstract: It is necessary to test it on a dummy coil, before using a magnet power supply (MPS) to energize a Poloidal Field (PF) coil in the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The dummy coil should accept the same large current from the MPS as the PF coil and be within the capability of the utilities located at the KSTAR site. Therefore a coil design based on the characteristics of the MPS and other restrictive conditions needed to be made. There are three requirements to be met in the design: an electrical requirement, a structural requirement, and a water cooling requirement. The electrical requirement was that the coil should have an inductance of 40 mH. For the structural requirement, the material should be non magnetic. The coil support structure and water cooling manifold were made of SUS 304. The water cooling requirement was that there should be sufficient flow rate so that the temperature rise ΔT should not exceed 12 °C for operation at 12.5 kA for 5 min. Square cross-section hollow conductor with dimensions of 38.1 mm × 38.1 mm was used with a 25.4 mm center hole for cooling water. However, as a result of tests, it was found that the electrical and structural requirements were satisfied but that the water cooling was over designed. It is imperative that the verification will be redone for a test with 12.5 kA for 5 min.

ANL experimental program for pulsed superconducting coils

International Nuclear Information System (INIS)

Wang, S.T.; Kim, S.H.; Praeg, W.F.; Krieger, C.I.

1978-01-01

Argonne National Laboratory (ANL) had recognized the clear advantage of a superconducting ohmic-heating (OH) coil and started in aggressive development program in FY 1977. The main objectives for FY 1977 are to develop cryostable basic cable configurations with reasonably low ac losses, to develop 12 kA cryostable cable, using it to design and build a 1.5 MJ pulsed coil, and to develop a rather inexpensive large fiberglass reinforced helium cryostat for the 1.5 MJ pulsed coil. The principal objective in building the 1.5 MJ ac coil is to demonstrate ac cryostability of a large coil ranging from 2 T/s up to 12 T/s. Another objective in the pulsed coil program is to determine the feasibility of parallel coil operation in order to avoid excessive voltage and current requirements and to minimize the number of turns for the equilibrium field (EF) coils, should the EF coils be connected in parallel with the OH coils. A two-coil section model using the 11 kA cable will be built and tested

ANL experimental program for pulsed superconducting coils

International Nuclear Information System (INIS)

Wang, S.T.; Kim, S.H.; Praeg, W.F.; Krieger, C.I.

1977-01-01

Argonne National Laboratory (ANL) had recognized the clear advantage of a superconducting ohmic-heating (OH) coil and started an aggressive development program in FY 1977. The main objectives for FY 1977 are to develop cryostable basic cable configurations with reasonably low ac losses, to develop 12 kA cryostable cable, using it to design and build a 1.5 MJ pulsed coil, and to develop a rather inexpensive large fiberglass reinforced helium cryostat for the 1.5 MJ pulsed coil. The principal objective in building the 1.5 MJ ac coil is to demonstrate ac cryostability of a large coil ranging from 2 T/s up to 12 T/s. Another objective in the pusled coil program is to determine the feasibility of parallel coil operation in order to avoid excessive voltage and current requirements and to minimize the number of turns for the equilibrium field (EF) coils, should the EF coils be connected in parallel with the OH coils. A two-coil section model using the 11 kA cable will be built and tested

INVESTIGATION OF SINGLE-PASS/DOUBLE-PASS TECHNIQUES ON FRICTION STIR WELDING OF ALUMINIUM

Directory of Open Access Journals (Sweden)

N.A.A. Sathari

2014-12-01

Full Text Available The aim of this research is to study the effects of single-pass/ double-pass techniques on friction stir welding of aluminium. Two pieces of AA1100 with a thickness of 6.0 mm were friction stir welded using a CNC milling machine at rotational speeds of 1400 rpm, 1600 rpm and 1800 rpm respectively for single-pass and double-pass. Microstructure observations of the welded area were studied using an optical microscope. The specimens were tested by using a tensile test and Vickers hardness test to evaluate their mechanical properties. The results indicated that, at low rotational speed, defects such as ‘surface lack of fill’ and tunnels in the welded area contributed to a decrease in mechanical properties. Welded specimens using double-pass techniques show increasing values of tensile strength and hardness. From this investigation it is found that the best parameters of FSW welded aluminium AA1100 plate were those using double-pass techniques that produce mechanically sound joints with a hardness of 56.38 HV and 108 MPa strength at 1800 rpm compared to the single-pass technique. Friction stir welding, single-pass/ double-pass techniques, AA1100, microstructure, mechanical properties.

Productive international collaboration in the large coil task

International Nuclear Information System (INIS)

Haubenreich, P.N.; Komarek, P.; Shimamoto, S.; Vecsey, G.

1987-01-01

The Large Coil Task (LCT), initiated in 1977, has been very productive of useful technical information about superconducting toroidal field (TF) coil design and manufacture. Moreover, it has demonstrated close international collaboration in fusion technology development, including integration of large components built in four different countries. Each of six 40-t test coils was designed and produced by a major industrial team, with government laboratory guidance, to a common set of specifications. The six were assembled into a toroidal array for testing in the International Fusion Superconducting Magnet Test Facility (IFSMTF) at Oak Ridge. Testing was done by a team of representatives of EURATOM, Japan, Switzerland, and the United States, with each participant having full access to all data. Coils were thoroughly instrumented, enabling penetrating analysis of behavior

Extending the self-assembly of coiled-coil hybrids

NARCIS (Netherlands)

Robson Marsden, Hana

2009-01-01

Of the various biomolecular building blocks in use in nature, coiled-coil forming peptides are amongst those with the most potential as building blocks for the synthetic self-assembly of nanostructures. Native coiled coils have the ability to function in, and influence, complex systems composed of

The Swiss LCT-coil

International Nuclear Information System (INIS)

Vecsey, G.; Benz, H.; Horvath, I.

1985-01-01

With delivery of the coil to ORNL on February 4, 1984, the second phase of the Swiss Large Coil Program - design and construction - was terminated. Mainlines of the Swiss design concept are summarized and related to theoretical calculations, experimental results of the supporting program, fabricational experience and first successful test results. An attempt is made to draw preliminary conclusions with regard to the design of future toroidal systems such as NET

Finite element modeling of TFTR poloidal field coils

International Nuclear Information System (INIS)

Baumgartner, J.A.; O'Toole, J.A.

1986-01-01

The Tokamak Fusion Test Reactor (TFTR) Poloidal Field (PF) coils were originally analyzed to TFTR design conditions. The coils have been reanalyzed by PPPL and Grumman to determine operating limits under as-built conditions. Critical stress levels, based upon data obtained from the reanalysis of each PF coil, are needed for input to the TFTR simulation code algorithms. The primary objective regarding structural integrity has been to ascertain the magnitude and location of critical internal stresses in each PF coil due to various combinations of electromagnetic and thermally induced loads. For each PF coil, a global finite element model (FEM) of a coil sector is being analyzed to obtain the basic coil internal loads and displacements. Subsequent fine mesh local models of the coil lead stem and lead spur regions produce the magnitudes and locations of peak stresses. Each copper turn and its surrounding insulation are modeled using solid finite elements. The corresponding electromagnetic and thermal analyses are similarly modeled. A series of test beams were developed to determine the best combination of MSC/NASTRAN-type finite elements for use in PF coil analysis. The results of this analysis compare favorably with those obtained by the earlier analysis which was limited in scope

Electromagnetic-coil (EM-coil) measurement technique to verify presence of metal/absence of oxide attribute

International Nuclear Information System (INIS)

Fuller, J.L.; Hockey, R.L.

2001-01-01

range between 10 -6 and 10 -20 mhos/meter, while the metals and alloys typically span a range between 7x10 7 and 5x10 5 mhos/meter. Measurements have been made using materials spanning both ends of each range. The EM coil method operates on the basis of Faraday's Law of induction. An alternating low-voltage signal is applied to an encircling coil at a selected frequency, generating a magnetic field at a storage containers surface. An electric field, of the same frequency, is generated in all metal objects placed inside the coil. The intensity of this electric field diminishes with depth into a metal. This electric field then causes electric current (commonly referred to as eddy current) to flow throughout conductive objects. As these induced currents flow they also generate a secondary magnetic field causing the coils impedance to change in proportion to the total magnetic field passing through the coil. A high-precision, impedance measuring device can monitor the coil's impedance and thus obtain an electromagnetic signature for all conductive objects placed inside the coil. The EM-coil is inherently less intrusive than a radiation measurement since it is sensitive to the combination of configuration and composition. On a mathematical basis, component information cannot be extracted from this measurement because the coil impedance is a two-parameter quantity and the number of parameters affecting the coil impedance is much greater than two. The EM-coil method can make a determination that a container does or does not enclose metal in the expected configuration. Radiation detection methods on the other hand may only be able to establish the lack of oxide, which thereby implies the presence of metal, a weaker statement. The EM-coil data analysis is extremely simple, requiring the definition of a region of interest in a two- dimensional plot. The EM-coil method is able to make a measurement in less than a minute, whereas radiation measurement methods demonstrated to

The bar coil for NMR tomograph

International Nuclear Information System (INIS)

Bogorodzki, P.; Piatkowski, A.; Wasielewski, J.

1995-01-01

The bar coil (bi-planar) for the NMR tomograph, designed for medical diagnostics, has been described. The tests of coil shown that it generates good homogenous magnetic field in a big volume what results in improving of the signal-to-noise ratio

Full-scale locomotive dynamic crash testing and correlations : locomotive consist colliding with steel coil truck at grade crossing (test 3).

Science.gov (United States)

2011-09-01

This report presents the test results and finite element correlations of a full-scale dynamic collision between a locomotive and a highway truck loaded with two heavy steel coils. The locomotive consist was moving at 58 miles per hour before it struc...

Assessment of a PML Boundary Condition for Simulating an MRI Radio Frequency Coil

Directory of Open Access Journals (Sweden)

Yunsuo Duan

2008-01-01

Full Text Available Computational methods such as the finite difference time domain (FDTD play an important role in simulating radiofrequency (RF coils used in magnetic resonance imaging (MRI. The choice of absorbing boundary conditions affects the final outcome of such studies. We have used FDTD to assess the Berenger's perfectly matched layer (PML as an absorbing boundary condition for computation of the resonance patterns and electromagnetic fields of RF coils. We first experimentally constructed a high-pass birdcage head coil, measured its resonance pattern, and used it to acquire proton (1H phantom MRI images. We then computed the resonance pattern and B1 field of the coil using FDTD with a PML as an absorbing boundary condition. We assessed the accuracy and efficiency of PML by adjusting the parameters of the PML and comparing the calculated results with measured ones. The optimal PML parameters that produce accurate (comparable to the experimental findings FDTD calculations are then provided for the birdcage head coil operating at 127.72 MHz, the Larmor frequency of 1H at 3 Tesla (T.

Conductor qualification tests for the 30-MJ Bonneville Power Administration SMES coil

International Nuclear Information System (INIS)

Schermer, R.I.; Boenig, H.J.; Henke, M.; Turner, R.D.; Schramm, R.

1980-01-01

The 30-MJ energy storage coil for the Bonneville Power Administration requires a low-loss, cryostable conductor that is able to carry 4.9 kA in a field of 2.8 T and will maintain its properties over 10 8 partial discharge cycles. The multi-level cable which satisfies these requirements has been extensively tested at various stages in its development and in its final form. Tests have been performed to determine the effect of manufacturing options on ac losses, low temperature electrical resistivity, stability, and fatigue resistance of the insulated conductor. This paper will concentrate on the stability and fatigue tests which have not previously been reported

High voltage investigations for ITER coils

International Nuclear Information System (INIS)

Fink, S.; Fietz, W.H.

2006-01-01

The superconducting ITER magnets will be excited with high voltage during operation and fast discharge. Because the coils are complex systems the internal voltage distribution can differ to a large extent from the ideal linear voltage distribution. In case of fast excitations internal voltages between conductor and radial plate of a TF coil can be even higher than the terminal voltage of 3.5 kV to ground which appears during a fast discharge without a fault. Hence the determination of the transient voltage distribution is important for a proper insulation co-ordination and will provide a necessary basis for the verification of the individual insulation design and the choice of test voltages and waveforms. Especially the extent of internal overvoltages in case of failures, e. g. malfunction of discharge units and / or arcing is of special interest. Transient calculations for the ITER TF coil system have been performed for fast discharge and fault scenarios to define test voltages for ITER TF. The conductor and radial plate insulation of the ITER TF Model Coil were exposed at room temperature to test voltages derived from the results from these calculations. Breakdown appeared during the highest AC voltage step. A fault scenario for the TF fast discharge system is presented where one fault triggers a second fault, leading to considerable voltage stress. In addition a FEM model of Poloidal Field Coil 3 for the determination of the parameters of a detailed network model is presented in order to prepare detailed investigations of the transient voltage behaviour of the PF coils. (author)

Surge analysis of the MAGLEV coil for propulsion and guidance; Jiki fujoshiki tetsudo ni okeru suitei annaiyo coil no surge kaiseki

Energy Technology Data Exchange (ETDEWEB)

Ema, S [Numazu College of Technology, Shizuoka (Japan)

1995-11-20

The MAGLEV (magnetically levitated train) is now well along in development testing in Japan. MAGLEV is unlike conventional railways, so various problems lie in the technology of MAGLEV. One of them is surge analysis of the MAGLEV coil for propulsion and guidance (`coil for propulsion` for short). The coil for propulsion is installed on each side of the outdoor guideway. Thus, the power system of MAGLEV is always exposed to lightning and circuit switching. Accordingly, it is very important to do a rational insulation plan to prevent damage when surges enter the coils. In view of this situation I performed experiments using the mini model coils and clarified impulse voltage distribution at the end of each coil and simulated the surge characteristics by giving the inverted L equivalent circuit to the coil for propulsion. As a result, the measured values and calculated values were almost equal in the surge characteristics. Further, the surge characteristics of the Miyazaki test track and the future MAGLEV were examined. 10 refs., 17 figs., 1 tab.

Argonne National Laboratory superconducting pulsed coil program

International Nuclear Information System (INIS)

Wang, S.T.; Kim, S.H.

1979-01-01

The main objectives are to develop high current (approx. 100 kA) cryostable cable configurations with reasonably low ac losses, to build a demonstration pulsed coil, and to develop a rather inexpensive large fiberglass reinforced helium cryostat. A 1.5-MJ cryostable pulsed superconducting coil has been developed and constructed at ANL. The coil has a peak field of 4.5 T at an operating current of 11.0 kA. A large inexpensive plastic cryostat has been developed for testing the pulsed coil. The coil has been pulsed with a maximum dB/dt of 11 T/s. The coil was pulsed more than 4000 cycles. Detailed results of the ac loss measurements and the current sharing of the cryostability will be described

Fabrication of the KSTAR toroidal field coil structure

International Nuclear Information System (INIS)

Choi, C.H.; Sa, J.W.; Park, H.K.; Hong, K.H.; Shin, H.; Kim, H.T.; Bak, J.S.; Lee, G.S.; Kwak, J.H.; Moon, H.G.; Yoon, H.H.; Lee, J.W.; Lee, S.K.; Song, J.Y.; Nam, K.M.; Byun, S.E.; Kim, H.C.; Ha, E.T.; Ahn, H.J.; Kim, D.S.; Lee, J.S.; Park, K.H.; Hong, C.D.

2005-01-01

The KSTAR toroidal field (TF) coil structure is under fabrication upon completion of engineering design and prototype construction. The prototype TF coil structure has been fabricated within allowable tolerances. Encasing of the prototype TF coil (TF00) in the prototype structure has been carried out through major processes involving a coil encasing, an enclosing weld, a vacuum pressure impregnation, and an outer surface machining. During the enclosing weld of the TF00 coil structure, we have measured temperatures and stresses on the coil surface. Assembly test had been performed with the TF00 coil structure. We have chosen Type 316LN as material of the TF coil structure. We used the narrow-gap TIG welding method. Doosan Heavy Industries and Construction Company (DHI) will complete the fabrication of the TF coil structure in Feb. 2006. (author)

Measurement of a Conduction Cooled Nb3Sn Racetrack Coil

Science.gov (United States)

Kim, HS; Kovacs, C.; Rochester, J.; Sumption, MD; Tomsic, M.; Peng, X.; Doll, D.

2017-12-01

Use of superconducting coils for wind turbines and electric aircraft is of interest because of the potential for high power density and weight reduction. Here we test a racetrack coil developed as a proof-of-concept for cryogen-free superconducting motors and generators. The coil was wound with 1209 m of 0.7-mm-diameter insulated tube-type Nb3Sn wire. The coil was epoxy-impregnated, instrumented, covered with numerous layers of aluminized mylar insulation, and inserted vertically into a dewar. The system was cooled to 4.2 K, and a few inches of liquid helium was allowed to collect at the bottom of the dewar but below the coil. The coil was cooled by conduction via copper cooling bars were attached to the coil but also were immersed in the liquid helium at their lower ends. Several current tests were performed on the coil, initially in voltage mode, and one run in current mode. The maximum coil Ic at 4.2 K was 480 A, generating 3.06 T at the surface of the coil. The coil met the design targets with a noticeable margin.

Modular coils: a promising toroidal-reactor-coil system

International Nuclear Information System (INIS)

Chu, T.K.; Furth, H.P.; Johnson, J.L.; Ludescher, C.; Weimer, K.E.

1981-04-01

The concept of modular coils originated from a need to find reactor-relevant stellarator windings, but its usefulness can be extended to provide an externally applied, additional rotational transform in tokamaks. Considerations of (1) basic principles of modular coils, (2) types of coils, (3) types of configurations (general, helically symmetric, helically asymmetric, with magnetic well, with magnetic hill), (4) types of rotational transform profile, and (5) structure and origin of ripples are given. These results show that modular coils can offer a wide range of vacuum magnetic field configurations, some of which cannot be obtained with the classical stellarator or torsatron coil configuration

Coil protection calculator for TFTR

International Nuclear Information System (INIS)

Marsala, R.J.; Lawson, J.E.; Persing, R.G.; Senko, T.R.; Woolley, R.D.

1989-01-01

A new coil protection system (CPS) is being developed to replace the existing TFTR magnetic coil fault detector. The existing fault detector sacrifices TFTR operating capability for simplicity. The new CPS, when installed in October of 1988, will permit operation up to the actual coil stress limits parameters in real-time. The computation will be done in a microprocessor based Coil Protection Calculator (CPC) currently under construction at PPL. THe new CPC will allow TFTR to operate with higher plasma currents and will permit the optimization of pulse repetition rates. The CPC will provide real-time estimates of critical coil and bus temperatures and stresses based on real-time redundant measurements of coil currents, coil cooling water inlet temperature, and plasma current. The critical parameter calculations are compared to prespecified limits. If these limits are reached or exceeded, protection action will be initiated to a hard wired control system (HCS), which will shut down the power supplies. The CPC consists of a redundant VME based microprocessor system which will sample all input data and compute all stress quantities every ten milliseconds. Thermal calculations will be approximated every 10ms with an exact solution occurring every second. The CPC features continuous cross-checking of redundant input signal, automatic detection of internal failure modes, monitoring and recording of calculated results, and a quick, functional verification of performance via an internal test system. (author)

Investigation of the mechanical and electrical properties of superconducting coils

International Nuclear Information System (INIS)

Saito, T.; Yamagiwa, T.; Hara, K.; Kojima, Y.; Hosoyama, K.; Mori, A.; Nojima, K.; Okamoto, Y.; Takabayashi, S.; Tanaka, T.

1994-01-01

Measurement of elastic (Young's) modulus of the superconducting coil and electrical punch-through test have been performed at LBL to understand the mechanical and electrical properties of the superconducting coils. The authors have investigated the elastic modulus of the superconducting coils with six kinds of insulators (made with polyimide-fiberglass-epoxy and all polyimide insulation with epoxy/polyimide adhesive) at room and liquid nitrogen temperatures using samples made of 10 stacks of superconducting cables. The samples are cured under varying compression to investigate the curing pressure dependence of Young's modulus of the coils with six kinds of the insulation system. The electrical punch-through test has also performed under compression at room and liquid nitrogen temperatures to investigate electrical integrity of the insulated coils. The tensile strength test of four kinds of polyimide films has been performed at various temperatures (between cryogenic and coil curing temperatures) to understand the mechanical properties of the films

Large-coil-test-facility fault-tree analysis

International Nuclear Information System (INIS)

1982-01-01

An operating-safety study is being conducted for the Large Coil Test Facility (LCTF). The purpose of this study is to provide the facility operators and users with added insight into potential problem areas that could affect the safety of personnel or the availability of equipment. This is a preliminary report, on Phase I of that study. A central feature of the study is the incorporation of engineering judgements (by LCTF personnel) into an outside, overall view of the facility. The LCTF was analyzed in terms of 32 subsystems, each of which are subject to failure from any of 15 generic failure initiators. The study identified approximately 40 primary areas of concern which were subjected to a computer analysis as an aid in understanding the complex subsystem interactions that can occur within the facility. The study did not analyze in detail the internal structure of the subsystems at the individual component level. A companion study using traditional fault tree techniques did analyze approximately 20% of the LCTF at the component level. A comparison between these two analysis techniques is included in Section 7

CCHMM_PROF: a HMM-based coiled-coil predictor with evolutionary information

DEFF Research Database (Denmark)

Bartoli, Lisa; Fariselli, Piero; Krogh, Anders

2009-01-01

tools are available for predicting coiled-coil domains in protein sequences, including those based on position-specific score matrices and machine learning methods. RESULTS: In this article, we introduce a hidden Markov model (CCHMM_PROF) that exploits the information contained in multiple sequence...... alignments (profiles) to predict coiled-coil regions. The new method discriminates coiled-coil sequences with an accuracy of 97% and achieves a true positive rate of 79% with only 1% of false positives. Furthermore, when predicting the location of coiled-coil segments in protein sequences, the method reaches...

Investigation of the mechanical properties of the Euratom LCT coil by tests under different boundary conditions

International Nuclear Information System (INIS)

Maurer, A.; Komarek, P.; Maurer, W.; Ulbricht, A.; Wuechner, F.

1987-01-01

The increasing size of superconducting magnets for fusion and other application requires a careful design of the mechanical support structure to avoid expensive overdesign or damage. An encouraging progress was made in this field during the last ten years. Requirements of the Large Coil Task, a program to develop superconducting magnets suitable for TOKAMAKS, made it indispensable to transfer the already existing calculation of the finite element method (FEM) to the field of superconducting magnet technology. There are some conditions which require an additional effort and extension of the FEM models for the usage in this field. As a consequence of the operation at low temperatures material data must be available over the whole temperature range. The winding and the conductor of superconducting coils is a sophisticated composite with orthotropic material properties which have to be determined by suitable detailed FEM models and which have to be also checked by measurements on test samples of the winding pack. In most cases an additional structure of stainless steel or fiberglass reinforced epoxy is necessary to support the winding pack. Therefore a suitable model representing the elastic properties of the mechanism of force transmission has to be introduced in the FEM calculations. The mechanical measurements on a superconducting coil confirm or show weak points of the model and close therefore existing gaps. The Euratom LCT coil is equipped with sensors (strain gauges rosettes, displacement transducers) to analyse local and global structural mechanical behaviour. The spectrum of load cases applied during the testing with partly varying boundary conditions offers an excellent experimental frame to elucidate hidden uncovered model problem areas. (orig.)

Pressure rise analysis in superconducting coils during dumping

International Nuclear Information System (INIS)

Tada, E.; Shimamoto, S.

1984-01-01

This chapter describes the ALPHE computer code, whose purpose is to calculate transient helium behavior in a poolboiling coil and to determine suitable characteristics of safety devices to minimize the maximum pressure and the liquid helium lost during dumping due to quench, or when discharging without normalcy. The analysis is compared with the measurements obtained in the domestic test of the Japanese LCT coil. Topics considered include basic equations (helium behavior, heat generation), manual dump without quench, and dumping due to quench. It is demonstrated that the transient behavior, calculated by ALPHE assuming quasi-static equilibrium between helium and coil, is in good agreement with the experimental measurements observed in the domestic test of the Japanese LCT coil. The engineering technique required for the design criteria of superconducting coils and safety device during dumping is established. ALPHE can be used to design an emergency safety system for a helium refrigerator during dumping

Sensitive quench detection of the HTS coil using a co-winding coil

International Nuclear Information System (INIS)

Takagi, Tomohiro; Ariyama, Takahiro; Takao, Tomoaki; Tsukamoto, Osami

2017-01-01

The authors have studied the co-winding coil method (CW method) using the co-wound coil electrically insulated from the HTS coil. In this method, the quench is detected by the voltage difference between the coil of the HTS tape (HTS coil) and the coil of the normal conductor (CW coil). The voltage induced in the CW coil caused by the change of the magnetic field is almost the same as that in the HTS coil because the coils are magnetically coupled close to each other. Therefore, it is expected that the induced voltage will be canceled with high accuracy and that the resistive voltage in the HTS coil will be detected with greater sensitivity compared to the bridge balance method, which is used commonly. In this study, quench detection applying the CW method is demonstrated using an experimental double-pancake coil. A tape with the copper layer deposited on the polymer substrate was used as the insulated conductor wire to form the CW coil. An additional pancake coil was used to expose the experimental double-pancake coil to the external magnetic field asymmetrically. It was shown that the CW method can detect the resistive voltage with greater sensitivity even when the HTS coil was exposed to the changing asymmetric external magnetic field. (author)

An Air Bearing Rotating Coil Magnetic Measurement System

CERN Document Server

Gottschalk, Stephen C; Taylor, David J; Thayer, William

2005-01-01

This paper describes a rotating coil magnetic measurement system supported on air bearings. The design is optimized for measurements of 0.1micron magnetic centerline changes on long, small aperture quadrupoles. Graphite impregnated epoxy resin is used for the coil holder and coil winding forms. Coil holder diameter is 11 mm with a length between supports of 750mm. A pair of coils is used to permit quadrupole bucking during centerline measurements. Coil length is 616mm, inner radius 1.82mm, outer radius 4.74mm. The key features of the mechanical system are simplicity; air bearings for accurate, repeatable measurements without needing warm up time and a vibration isolated stand that uses a steel-topped Newport optical table with air suspension. Coil rotation is achieved by a low noise servo motor controlled by a standalone Ethernet servo board running custom servo software. Coil calibration procedures that correct wire placement errors, tests for mechanical resonances, and other system checks will also be discu...

How My Program Passed the Turing Test

Science.gov (United States)

Humphrys, Mark

In 1989, the author put an ELIZA-like chatbot on the Internet. The conversations this program had can be seen - depending on how one defines the rules (and how seriously one takes the idea of the test itself) - as a passing of the Turing Test. This is the first time this event has been properly written. This chatbot succeeded due to profanity, relentless aggression, prurient queries about the user, and implying that they were a liar when they responded. The element of surprise was also crucial. Most chatbots exist in an environment where people expectto find some bots among the humans. Not this one. What was also novel was the onlineelement. This was certainly one of the first AI programs online. It seems to have been the first (a) AI real-time chat program, which (b) had the element of surprise, and (c) was on the Internet. We conclude with some speculation that the future of all of AI is on the Internet, and a description of the "World- Wide-Mind" project that aims to bring this about.

Structure design of the Westinghouse superconducting magnet for the Large Coil Program

International Nuclear Information System (INIS)

Domeisen, F.N.; Hackworth, D.T.; Stuebinger, L.R.

1978-01-01

In the on-going development of superconducting toroidal field coils for tokamak reactors, the Large Coil Program (LCP) managed by Union Carbide Corporation will include the design, fabrication, and testing of large superconducting coils to determine their feasibility for use in the magnetic fusion energy effort. Structural analysis of the large coil is essential to ensure adequate safety in the test coil design and confidence in the scalability of the design. This paper will discuss the action of tensile and shear loads on the various materials used in the coil. These loads are of magnetic and thermal origin

A new design of SMES coil for bridging instantaneous voltage dips

International Nuclear Information System (INIS)

Kurusu, T; Ono, M; Ogata, H; Tosaka, T; Senda, I; Nomura, S

2006-01-01

This paper describes a new design concept of SMES coil for bridging instantaneous dips and some experimental results. The technical key point of this work is the design of a NbTi coil composed of a monolith NbTi/Cu wire for DC application. In order to cover the disadvantages of the monolith wire, some solutions have been proposed and tested using a fullscale test coil. Experimental results show the validity of the design concept of the SMES coil

The significant impact of framing coils on long-term outcomes in endovascular coiling for intracranial aneurysms: how to select an appropriate framing coil.

Science.gov (United States)

Ishida, Wataru; Sato, Masayuki; Amano, Tatsuo; Matsumaru, Yuji

2016-09-01

OBJECTIVE The importance of a framing coil (FC)-the first coil inserted into an aneurysm during endovascular coiling, also called a lead coil or a first coil-is recognized, but its impact on long-term outcomes, including recanalization and retreatment, is not well established. The purposes of this study were to test the hypothesis that the FC is a significant factor for aneurysmal recurrence and to provide some insights on appropriate FC selection. METHODS The authors retrospectively reviewed endovascular coiling for 280 unruptured intracranial aneurysms and gathered data on age, sex, aneurysm location, aneurysm morphology, maximal size, neck width, adjunctive techniques, recanalization, retreatment, follow-up periods, total volume packing density (VPD), volume packing density of the FC, and framing coil percentage (FCP; the percentage of FC volume in total coil volume) to clarify the associated factors for aneurysmal recurrence. RESULTS Of 236 aneurysms included in this study, 33 (14.0%) had recanalization, and 18 (7.6%) needed retreatment during a mean follow-up period of 37.7 ± 16.1 months. In multivariate analysis, aneurysm size (odds ratio [OR] = 1.29, p < 0.001), FCP < 32% (OR 3.54, p = 0.009), and VPD < 25% (OR 2.96, p = 0.015) were significantly associated with recanalization, while aneurysm size (OR 1.25, p < 0.001) and FCP < 32% (OR 6.91, p = 0.017) were significant predictors of retreatment. VPD as a continuous value or VPD with any cutoff value could not predict retreatment with statistical significance in multivariate analysis. CONCLUSIONS FCP, which is equal to the FC volume as a percentage of the total coil volume and is unaffected by the morphology of the aneurysm or the measurement error in aneurysm length, width, or height, is a novel predictor of recanalization and retreatment and is more significantly predictive of retreatment than VPD. To select FCs large enough to meet the condition of FCP ≥ 32% is a potential relevant factor for better

Program NICOLET to integrate energy loss in superconducting coils

International Nuclear Information System (INIS)

Vogel, H.F.

1978-08-01

A voltage pickup coil, inductively coupled to the magnetic field of the superconducting coil under test, is connected so its output may be compared with the terminal voltage of the coil under test. The integrated voltage difference is indicative of the resistive volt-seconds. When multiplied with the main coil current, the volt-seconds yield the loss. In other words, a hysteresis loop is obtained if the integrated voltage difference phi = ∫ΔVdt is plotted as a function of the coil current, i. First, time functions of the two signals phi(t) and i(t) are recorded on a dual-trace digital oscilloscope, and these signals are then recorded on magnetic tape. On a CDC-6600, the recorded information is decoded and plotted, and the hysteresis loops are integrated by the set of FORTRAN programs NICOLET described in this report. 4 figures

Empirical component model to predict the overall performance of heating coils: Calibrations and tests based on manufacturer catalogue data

International Nuclear Information System (INIS)

Ruivo, Celestino R.; Angrisani, Giovanni

2015-01-01

Highlights: • An empirical model for predicting the performance of heating coils is presented. • Low and high heating capacity cases are used for calibration. • Versions based on several effectiveness correlations are tested. • Catalogue data are considered in approach testing. • The approach is a suitable component model to be used in dynamic simulation tools. - Abstract: A simplified methodology for predicting the overall behaviour of heating coils is presented in this paper. The coil performance is predicted by the ε-NTU method. Usually manufacturers do not provide information about the overall thermal resistance or the geometric details that are required either for the device selection or to apply known empirical correlations for the estimation of the involved thermal resistances. In the present work, heating capacity tables from the manufacturer catalogue are used to calibrate simplified approaches based on the classical theory of heat exchangers, namely the effectiveness method. Only two reference operating cases are required to calibrate each approach. The validity of the simplified approaches is investigated for a relatively high number of operating cases, listed in the technical catalogue of a manufacturer. Four types of coils of three sizes of air handling units are considered. A comparison is conducted between the heating coil capacities provided by the methodology and the values given by the manufacturer catalogue. The results show that several of the proposed approaches are suitable component models to be integrated in dynamic simulation tools of air conditioning systems such as TRNSYS or EnergyPlus

Optimization of Coil Element Configurations for a Matrix Gradient Coil.

Science.gov (United States)

Kroboth, Stefan; Layton, Kelvin J; Jia, Feng; Littin, Sebastian; Yu, Huijun; Hennig, Jurgen; Zaitsev, Maxim

2018-01-01

Recently, matrix gradient coils (also termed multi-coils or multi-coil arrays) were introduced for imaging and B 0 shimming with 24, 48, and even 84 coil elements. However, in imaging applications, providing one amplifier per coil element is not always feasible due to high cost and technical complexity. In this simulation study, we show that an 84-channel matrix gradient coil (head insert for brain imaging) is able to create a wide variety of field shapes even if the number of amplifiers is reduced. An optimization algorithm was implemented that obtains groups of coil elements, such that a desired target field can be created by driving each group with an amplifier. This limits the number of amplifiers to the number of coil element groups. Simulated annealing is used due to the NP-hard combinatorial nature of the given problem. A spherical harmonic basis set up to the full third order within a sphere of 20-cm diameter in the center of the coil was investigated as target fields. We show that the median normalized least squares error for all target fields is below approximately 5% for 12 or more amplifiers. At the same time, the dissipated power stays within reasonable limits. With a relatively small set of amplifiers, switches can be used to sequentially generate spherical harmonics up to third order. The costs associated with a matrix gradient coil can be lowered, which increases the practical utility of matrix gradient coils.

Split-coil-system SULTAN

International Nuclear Information System (INIS)

Vecsey, G.

1992-08-01

The high field superconductor test facility SULTAN started operation successfully in May 1992. Originally designed for testing full scale conductors for the large magnets of the next generation fusion reactors, the SULTAN facility installed at PSI (Switzerland) was designed as a common venture of three European Laboratories: ENEA (Italy), ECN (Netherlands) and PSI, and built by ENEA and PSI in the framework of the Euratom Fusion Technology Program. Presently the largest facility in the world, with its superconducting split coil system generating 11 Tesla in a 0.6 m bore, it is ready now for testing superconductor samples with currents up to 50 kA at variable cooling conditions. Similar tests can be arranged also for other applications. SULTAN is offered by the European Community as a contribution to the worldwide cooperation for the next step of fusion reactor development ITER. First measurements on conductor developed by CEA (Cadarache) are now in progress. Others like those of ENEA and CERN will follow. For 1993, a test of an Italian 12 TZ model coil for fusion application is planned. SULTAN is a worldwide unique facility marking the competitive presence of Swiss technology in the field of applied superconductivity research. Based on development and design of PSI, the high field Nb 3 Sn superconductors and coils were fabricated at the works of Kabelwerke Brugg and ABB, numerous Swiss companies contributed to the success of this international effort. Financing of the Swiss contribution of SULTAN was made available by NEFF, BEW, BBW, PSI and EURATOM. (author) figs., tabs., 20 refs

Role of the large coil program in the development of superconducting magnets for fusion reactors

International Nuclear Information System (INIS)

Haubenreich, P.N.; Luton, J.N.; Thompson, P.B.

1978-01-01

Three U.S. industrial teams are designing and will build one coil each to a common set of specifications. Coil specifications and test conditions were chosen to insure maximum relevance to fusion program needs. Each test coil will have a 2.5 x 3.5 m D-shape bore, will contain about 7 MA-turns, and must operate at a peak field of 8 T while subjected to pulsed fields up to 0.14 T in a test stand that can accommodate up to 6 coils in a compact toroidal array. Coils by General Dynamics/Convair and General Electric will use different NbTi conductors cooled by pool-boiling helium. The Westinghouse coil will use Nb 3 Sn cooled by a forced flow of supercritical helium. These coils will be delivered in 1980 and 1981 for testing in the Large Coil Test Facility at Oak Ridge in a compact toroidal array with three coils from outside the U.S. These will be produced by EURATOM, Japan, and Switzerland for testing under an International Energy Agency agreement

[Surface coils for magnetic-resonance images].

Science.gov (United States)

Rodríguez-González, Alfredo Odón; Amador-Baheza, Ricardo; Rojas-Jasso, Rafael; Barrios-Alvarez, Fernando Alejandro

2005-01-01

Since the introduction of magnetic resonance imaging in Mexico, the development of this important medical imaging technology has been almost non-existing in our country. The very first surface coil prototypes for clinical applications in magnetic resonance imaging has been developed at the Center of Research in Medical Imaging and Instrumentation of the Universidad Autónoma Metropolitana Iztapalapa (Metropolitan Autonomous University, Campus Iztapalapa). Two surface coil prototypes were built: a) a circular-shaped coil and b) a square-shaped coil for multiple regions of the body, such as heart, brain, knee, hands, and ankles. These coils were tested on the 1.5T imager of the ABC Hospital-Tacubaya, located in Mexico City. Brain images of healthy volunteers were obtained in different orientations: sagittal, coronal, and axial. Since images showed a good-enough clinical quality for diagnosis, it is fair to say that these coil prototypes can be used in the clinical environment, and with small modifications, they can be made compatible with almost any commercial scanner. This type of development can offer new alternatives for further collaboration between the research centers and the radiology community, in the search of new applications and developments of this imaging technique.

Development of superconducting pulsed poloidal coil in JAERI

International Nuclear Information System (INIS)

Shimamoto, S.; Okuno, K.; Ando, T.; Tsuji, H.

1990-01-01

In the Japan Atomic Energy Research Institute, (JAERI), development work on pulsed superconductors and coils started in 1979, aiming at the demonstration of the applicability of superconducting technologies to pulsed poloidal coils in a fusion reactor. Initially our effort was concentrated mainly on the development of pool-cooled large-current pulsed conductors. Over the past ten years, superconducting technology has made great progress and the forced-flow cooled coil has assumed great importance in the development work. Now the Demo Poloidal Coil Project is in progress in JAERI, and three large forced-flow cooled coils have so far been fabricated and tested. Many improvements have been achieved in ac-loss performance and mechanical characteristics. (author)

Triple Halo Coil: Development and Comparison with Other TMS Coils

Science.gov (United States)

Rastogi, Priyam; Hadimani, Ravi; Jiles, David

Transcranial Magnetic Stimulation (TMS) is a non-invasive stimulation technique that can be used for the treatment of various neurological disorders such as Parkinson's Disease, PTSD, TBI and anxiety by regulating synaptic activity. TMS is FDA approved for the treatment of major depressive disorder. There is a critical need to develop deep TMS coils that can stimulate deeper regions of the brain without excessively stimulating the cortex in order to provide an alternative to surgical methods. We have developed a novel multi-coil configuration called ``Triple Halo Coil'' (THC) that can stimulate deep brain regions. Investigation of induced electric and magnetic field in these regions have been achieved by computer modelling. Comparison of the results due to THC configuration have been conducted with other TMS coils such as ``Halo Coil'', circular coil and ``Figure of Eight'' coil. There was an improvement of more than 15 times in the strength of magnetic field, induced by THC configuration at 10 cm below the vertex of the head when compared with the ``Figure of Eight'' coil alone. Carver Charitable Trust.

Fabrication of the new poloidal field coils for DIII-D

International Nuclear Information System (INIS)

Heiberger, M.; Bott, R.J.; Gallix, R.; Street, R.W.

1986-01-01

The six new poloidal field coil assemblies manufactured by GA Technologies (GA) for DIII-D range in diameter from 3.4-5.3 m. Two of them are 55-turn field shaping coils. Each of the other four combines one turn of the ohmic heating coil and a 55-turn field shaping coil into a single unit encased in a stainless steel box beam. These four box beams, which provide support for the coils inside, are part of the overall coil and vacuum vessel support structure. They also serve as molds for vacuum impregnating the coils with epoxy. All coils are made of hollow, water-cooled copper conductor. The larger field shaping coils are designed for 20 kA, 3 sec rectangular current pulses with 40 0 C temperature rise. The ohmic heating coil turns are capable of currents of up to 110 kA. The conductor is wrapped with Kapton and fiberglass tape; Kapton provides 1000 V/turn and 28 kV coil-to-ground insulation. The fiberglass acts as wick and reinforcement for the vacuum impregnated epoxy resin which bonds the coil together. The fabrication process is described in detail and illustrated. Tools and setups used for special operations such as induction brazing, conductor winding, conductor bending, and vacuum impregnation are presented. The quality control procedures followed to guarantee sound brazed joints are explained. The electrical tests performed at several stages of fabrication, especially the 1000 V/turn impulse tests conducted before potting to facilitate fault detection and repair, are described

Biomaterials Made from Coiled-Coil Peptides.

Science.gov (United States)

Conticello, Vincent; Hughes, Spencer; Modlin, Charles

The development of biomaterials designed for specific applications is an important objective in personalized medicine. While the breadth and prominence of biomaterials have increased exponentially over the past decades, critical challenges remain to be addressed, particularly in the development of biomaterials that exhibit highly specific functions. These functional properties are often encoded within the molecular structure of the component molecules. Proteins, as a consequence of their structural specificity, represent useful substrates for the construction of functional biomaterials through rational design. This chapter provides an in-depth survey of biomaterials constructed from coiled-coils, one of the best-understood protein structural motifs. We discuss the utility of this structurally diverse and functionally tunable class of proteins for the creation of novel biomaterials. This discussion illustrates the progress that has been made in the development of coiled-coil biomaterials by showcasing studies that bridge the gap between the academic science and potential technological impact.

Updating the Design of the Poloidal Field Coils for the ITER Magnet System

International Nuclear Information System (INIS)

Yoshida, K.; Takahashi, Y.; Mitchell, N.; Jong, C.; Bessette, D.

2006-01-01

be disconnected and by-passed. This implies that the remaining pancakes are operated at a higher current as the backup mode. Since all PF coils include 8 double pancakes the backup mode involves operation at a current which is 8/7 of the nominal current. Jumpers are pre-installed on the coil surface to allow this reconnection with a minimum of works in the cryostat and the conductor is designed with an extra margin. (author)

Switching transients in the MFTF yin-yang coils

International Nuclear Information System (INIS)

Owen, E.W.; Shimer, D.W.

1982-01-01

This report is a study of the transients caused by the fast dump of large superconducting coils. Theoretical analysis, computer simulation, and actual measurements are used. Theoretical analysis can only be applied to the simplest of models. In the computer simulations two models are used, one in which the coil is divided into ten segments and another in which a single coil is employed. The circuit breaker that interrupts the current to the power supply, causing a fast dump, is represented by a time and current dependent conductance. Actual measurements are limited to measurements made incidental to the coils' performance tests

Persistent-current switch for pancake coils of rare earth-barium-copper-oxide high-temperature superconductor: Design and test results of a double-pancake coil operated in liquid nitrogen (77–65 K) and in solid nitrogen (60–57 K)

Energy Technology Data Exchange (ETDEWEB)

Qu, Timing; Michael, Philip C.; Bascuñán, Juan; Iwasa, Yukikazu, E-mail: iwasa@jokaku.mit.edu [Francis Bitter Magnet Laboratory, Plasma Science and Fusion Center, Massachusetts Institute of Technology, 170 Albany Street, Cambridge, Massachusetts 02139 (United States); Voccio, John [Wentworth Institute of Technology, 550 Huntington Ave, Boston, Massachusetts 02115 (United States); Hahn, Seungyong [National High Magnetic Field Laboratory, Florida State University, Tallahassee, 2031 Paul Dirac Drive, Florida 32310 (United States)

2016-08-22

We present design and test results of a superconducting persistent current switch (PCS) for pancake coils of rare-earth-barium-copper-oxide, REBCO, high-temperature superconductor (HTS). Here, a REBCO double-pancake (DP) coil, 152-mm ID, 168-mm OD, 12-mm high, was wound with a no-insulation technique. We converted a ∼10-cm long section in the outermost layer of each pancake to a PCS. The DP coil was operated in liquid nitrogen (77–65 K) and in solid nitrogen (60–57 K). Over the operating temperature ranges of this experiment, the normal-state PCS enabled the DP coil to be energized; thereupon, the PCS resumed the superconducting state and the DP coil field decayed with a time constant of 100 h, which would have been nearly infinite, i.e., persistent-mode operation, were the joint across the coil terminals superconducting.

Mechanical test of the model coil wound with large conductor

International Nuclear Information System (INIS)

Hiue, Hisaaki; Sugimoto, Makoto; Nakajima, Hideo; Yasukawa, Yukio; Yoshida, Kiyoshi; Hasegawa, Mitsuru; Ito, Ikuo; Konno, Masayuki.

1992-09-01

The high rigidity and strength of the winding pack are required to realize the large superconducting magnet for the fusion reactor. This paper describes mechanical tests concerning the rigidity of the winding pack. Samples were prepared to evaluate the adhesive strength between conductors and insulators. Epoxy and Bismaleimide-Triazine resin (BT resin) were used as the conductor insulator. The stainless steel (SS) 304 bars, whose surface was treated mechanically and chemically, was applied to the modeled conductor. The model coil was would with the model conductors covered with the insulator by grand insulator. A winding model combining 3 x 3 conductors was produced for measuring shearing rigidity. The sample was loaded with pure shearing force at the LN 2 temperature. The bar winding sample, by 8 x 6 conductors, was measured the bending rigidity. These three point bending tests were carried out at room temperature. The pancake winding sample was loaded with compressive forces to measure compressive rigidity of winding. (author)

CS model coil experimental log book

International Nuclear Information System (INIS)

Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi

2001-02-01

Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

Design and tests of a simplified divertor dummy coil structure for the WEST project

International Nuclear Information System (INIS)

Doceul, L.; Bucalossi, J.; Dougnac, H.; Ferlay, F.; Gargiulo, L.; Keller, D.; Larroque, S.; Lipa, M.; Pilia, A.; Saille, A.; Samaille, F.; Soler, B.; Thouvenin, D.; Verger, J.M.; Zago, B.; Portafaix, C.; Salami, M.

2015-01-01

Full text of publication follows. In order to fully validate actively cooled tungsten plasma facing components (industrial fabrication, operation with long plasma duration), the implementation of a tungsten axisymmetric divertor structure in the tokamak Tore-Supra is studied. With this major upgrade, so called WEST (Tungsten Environment in Steady state Tokamak), Tore-Supra will be able to address the problematic of long plasma discharges with a metallic divertor target. To do so, it is planned to install two symmetric divertor coils inside the vacuum vessel. This assembly, called divertor structure, is made up of two stainless steel casings containing a copper winding pack cooled by a pressurized hot water circuit (up to 200 Celsius degrees, 4 MPa) and is designed to perform steady state plasma operation (up to 1000 s). The divertor structure will be a complex assembly of 4 meter diameter and 4 meter height representing a total weight of around 20 tonnes. The technical challenge of this component will be the implementation of angular sectors inside the vacuum vessel environment (TIG welding of the coil casing, induction brazing and electrical insulation of the copper winding). Moreover, this complex assembly must sustain harsh environmental conditions in terms of ultra high vacuum conditions, mechanical loads (induced by disruptions) and electrical isolation (13 kV test) under high temperature. In order to fully validate the feasibility, the mounting and the performance of this complex component, the production of a scale one dummy coil is in progress. The paper will illustrate, the technical developments performed during 2012 in order to finalise the design for the call for tender phase. The progress and the first results of the simplified dummy coils will be also addressed. (authors)

Results of the international Large Coil Task: a milestone for superconducting magnets in fusion power

International Nuclear Information System (INIS)

Dresner, L.; Fietz, W.A.; Gauss, S.

1989-01-01

The aim of the Large Coil Task (LCT) was to demonstrate the reliable operation of large superconducting toroidal field coils and to prove the design principles and fabrication techniques to be applied for the magnets in a tokamak experimental power reactor. This has been achieved by an international development effort involving the US DOE, EURATOM, JAERI and the Swiss government. Six different D-shaped test coils were separately designed, developed and constructed by the LCT participants, then extensively tested together in a compact toroidal array. Detailed information on coil design and manufacture and all test data were shared among the LCT participants. The full six-coil array tests were carried out in a continuous period from the beginning of 1986 until September 1987. Beside the originally planned tests to reach an 8 T design point performance, the tests went well beyond this goal, reaching 9 T peak field in each coil. The experiments also delineated the limits of operability and demonstrated the coil safety under abnormal conditions. For fusion application the transient a.c. field behaviour in the coils was also of great interest. Three of the coils have been tested in this respect and showed excellent performance, with loss values in agreement with the theoretical predictions. (author)

Force delivery of Ni-Ti coil springs.

Science.gov (United States)

Manhartsberger, C; Seidenbusch, W

1996-01-01

Sentalloy springs (GAC, Central Islip, N.Y.) of the open and closed type were investigated with a special designed device. The closed coil springs were subjected to a tensile and the open coil springs to a compression test. After a first measurement, the springs were activated for a period of 4 weeks and then reinvestigated with the same procedure. It could be shown distinctly that, with the different coil springs, the force delivery given by the producer could be achieved only within certain limits. To remain in the martensitic plateau, changed activation ranges, and for the Sentalloy coil springs white and red of the open and closed type, also changed force deliveries had to be taken into account. There was a distinct decrease in force delivery between the first and second measurement. After considering the loading curves of all the Sentalloy coil springs and choosing the right activation range respective to the force delivery, it was found that the coil springs deliver a superior clinical behavior and open new treatment possibilities.

Development of a new error field correction coil (C-coil) for DIII-D

International Nuclear Information System (INIS)

Robinson, J.I.; Scoville, J.T.

1995-12-01

The C-coil recently installed on the DIII-D tokamak was developed to reduce the error fields created by imperfections in the location and geometry of the existing coils used to confine, heat, and shape the plasma. First results from C-coil experiments include stable operation in a 1.6 MA plasma with a density less than 1.0 x 10 13 cm -3 , nearly a factor of three lower density than that achievable without the C-coil. The C-coil has also been used in magnetic braking of the plasma rotation and high energy particle confinement experiments. The C-coil system consists of six individual saddle coils, each 60 degree wide toroidally, spanning the midplane of the vessel with a vertical height of 1.6 m. The coils are located at a major radius of 3.2 m, just outside of the toroidal field coils. The actual shape and geometry of each coil section varied somewhat from the nominal dimensions due to the large number of obstructions to the desired coil path around the already crowded tokamak. Each coil section consists of four turns of 750 MCM insulated copper cable banded with stainless steel straps within the web of a 3 in. x 3 in. stainless steel angle frame. The C-coil structure was designed to resist peak transient radial forces (up to 1,800 Nm) exerted on the coil by the toroidal and ploidal fields. The coil frames were supported from existing poloidal field coil case brackets, coil studs, and various other structures on the tokamak

Study of electric phenomena in energy dumping of LCT coil

International Nuclear Information System (INIS)

Oka, Koichi; Tsuji, Hiroshi; Nishi, Masataka; Shimamoto, Susumu

1980-03-01

In IEA-LCT coil, electric phenomena in energy dumping were studied analytically and experimentally. Protection resistance of the Japanese LCT coil is chosen as 0.1 Ω considering the quenching voltage, so that temperature rise of the coil is no problem. Energy dumping characteristic of the six-coil system is calculated under different conditions. It is concluded that simultaneous dumping of all the coils with the equivalent resistance values of protection is necessary. Flashover voltage tests of the model in 4.2 K liquid helium, 4.2 K gas helium and 4.2 K boiling helium show margin in practical quenching voltage of the coil. (author)

Conformational switching in the coiled-coil domains of a proteasomal ATPase regulates substrate processing.

Science.gov (United States)

Snoberger, Aaron; Brettrager, Evan J; Smith, David M

2018-06-18

Protein degradation in all domains of life requires ATPases that unfold and inject proteins into compartmentalized proteolytic chambers. Proteasomal ATPases in eukaryotes and archaea contain poorly understood N-terminally conserved coiled-coil domains. In this study, we engineer disulfide crosslinks in the coiled-coils of the archaeal proteasomal ATPase (PAN) and report that its three identical coiled-coil domains can adopt three different conformations: (1) in-register and zipped, (2) in-register and partially unzipped, and (3) out-of-register. This conformational heterogeneity conflicts with PAN's symmetrical OB-coiled-coil crystal structure but resembles the conformational heterogeneity of the 26S proteasomal ATPases' coiled-coils. Furthermore, we find that one coiled-coil can be conformationally constrained even while unfolding substrates, and conformational changes in two of the coiled-coils regulate PAN switching between resting and active states. This switching functionally mimics similar states proposed for the 26S proteasome from cryo-EM. These findings thus build a mechanistic framework to understand regulation of proteasome activity.

Quench evolution and hot spot temperature in the ATLAS B0 model coil

CERN Document Server

Dudarev, A; Boxman, H; Broggi, F; Dolgetta, N; Juster, F P; Tetteroo, M; ten Kate, H H J

2004-01-01

The 9-m long superconducting model coil B0 was built to verify design parameters and exercise the construction of the Barrel Toroid magnet of ATLAS Detector. The model coil has been successfully tested at CERN. An intensive test program to study quench propagation through the coil windings as well as the temperature distribution has been carried out. The coil is well equipped with pickup coils, voltage taps, superconducting quench detectors and temperature sensors. The current is applied up to 24 kA and about forty quenches have been induced by firing internal heaters. Characteristic numbers at full current of 24 kA are a normal zone propagation of 15 m/s in the conductor leading to a turn-to-turn propagation of 0.1 m/s, the entire coil in normal state within 5.5 s and a safe peak temperature in the windings of 85 K. The paper summarizes the quench performance of the B0 coil. Based on this experience the full-size coils are now under construction and first test results are awaited by early 2004. 7 Refs.

Switching transients in a superconducting coil

International Nuclear Information System (INIS)

Owen, E.W.; Shimer, D.W.

1983-01-01

A study is made of the transients caused by the fast dump of large superconducting coils. Theoretical analysis, computer simulation, and actual measurements are used. Theoretical analysis can only be applied to the simplest of models. In the computer simulations two models are used, one in which the coil is divided into ten segments and another in which a single coil is employed. The circuit breaker that interrupts the current to the power supply, causing a fast dump, is represented by a time and current dependent conductance. Actual measurements are limited to measurements made incidental to performance tests on the MFTF Yin-yang coils. It is found that the breaker opening time is the critical factor in determining the size and shape of the transient. Instantaneous opening of the breaker causes a lightly damped transient with large amplitude voltages to ground. Increasing the opening time causes the transient to become a monopulse of decreasing amplitude. The voltages at the external terminals are determined by the parameters of the external circuit. For fast opening times the frequency depends on the dump resistor inductance, the circuit capacitance, and the amplitude on the coil current. For slower openings the dump resistor inductance and the current determine the amplitude of the voltage to ground at the terminals. Voltages to ground are less in the interior of the coil, where transients related to the parameters of the coil itself are observed

Fabrication of built-up conductors for large pulsed coils

International Nuclear Information System (INIS)

Henke, M.D.; Schermer, R.I.

1979-01-01

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

The design of the SULTAN inner coil

International Nuclear Information System (INIS)

Franken, W.M.P.; Spoorenberg, C.J.G.

1981-12-01

The background field of the first phase of the test facility SULTAN will be generated by two concentric solenoids: a 6 Tesla outer coil with a free bore of 1.3 m and an inner coil for increasing the field to 8 Tesla. The free bore (cold) will be 1.055 m. The final design of the 8 Tesla inner coil is described. The coil will operate at an overall current density of 23 x 10 6 A/m 2 . It will be cooled directly by forced flow supercritical helium. A hollow conductor is applied, composed of a rectangular copper tube and a 16 strands Rutherford cable, soldered on one side of the tube. The copper tube will be cold worked to cope with the high stress level (165 MPa). The design base (field and stress analysis, cooling, stability), the mechanical design and the instrumentation will be specified. The design and construction of the coil is a part of the collaboration between ECN and Holec Transformer Group

Superconducting magnetic coil

Science.gov (United States)

Aized, Dawood; Schwall, Robert E.

1996-06-11

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

Magnetic resonance dacryocystography: comparison between conventional surface coils and microscopic coils

International Nuclear Information System (INIS)

Abreu Junior, Luiz de; Wolosker, Angela Maria Borri; Borri, Maria Lucia; Galvao Filho, Mario de Melo; Hartmann, Luiz Guilherme de Carvalho; D'Ippolito, Giuseppe; Castro, Claudio Campi de

2008-01-01

Objective: Magnetic resonance imaging has been utilized in the evaluation of the lacrimal apparatus with some advantages over conventional dacryocystography. The present study was aimed at acquiring high resolution images utilizing microscopic coils for evaluating typical structures of the lacrimal apparatus as compared with the findings observed with conventional surface coils. Materials and methods: Five asymptomatic volunteers with no history of epiphora were submitted to high-field magnetic resonance imaging with microscopic and conventional surface coils, and STIR sequence after instillation of saline solution. The definition of normal anatomic structures of lacrimal apparatuses was compared utilizing conventional and microscopic surface coils. Based on a consensual scoring system, the mean values for each structure were calculated by two observers. Results: In 90% of cases, higher scores were attributed to images acquired with the microscopic coil. On average, a 1.17 point increase was observed in the scoring of anatomic structures imaged with the microscopic coil. Additionally, a subjective improvement was observed in the signal-to-noise ratio with the microscopic coil. Conclusion: Magnetic resonance dacryocystography with microscopic coils is the appropriate method for evaluating the lacrimal apparatus, providing images with better quality as compared with those acquired with conventional surface coils. (author)

Progress of the ITER Correction Coils in China

CERN Document Server

Wei, J; Han, S; Yu, X; Du, S; Li, C; Fang, C; Wang, L; Zheng, W; Liu, L; Wen, J; Li, H; Libeyre, P; Dolgetta, N; Cormany, C; Sgobba, S

2014-01-01

The ITER Correction Coils (CC) include three sets of six coils each, distributed symmetrically around the tokamak to correct error fields. Each pair of coils, located on opposite sides of the tokamak, is series connected with polarity to produce asymmetric fields. The manufacturing of these superconducting coils is undergoing qualification of the main fabrication processes: winding into multiple pancakes, welding helium inlet/outlet on the conductor jacket, turn and ground insulation, vacuum pressure impregnation, inserting into an austenitic stainless steel case, enclosure welding, and assembling the terminal service box. It has been proceeding by an intense phase of R\\&D, trials tests, and final adjustment of the tooling. This paper mainly describes the progress in ASIPP for the CC manufacturing process before and on qualification phase and the status of corresponding equipment which are ordered or designed for each process. Some test results for the key component and procedure are also presented.

CS model coil experimental log book

Energy Technology Data Exchange (ETDEWEB)

Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

2001-02-01

Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

Compact stellarator coils

International Nuclear Information System (INIS)

Pomphrey, N.; Berry, L.A.; Boozer, A.H.

2001-01-01

Experimental devices to study the physics of high-beta (β>∼4%), low aspect ratio (A<∼4.5) stellarator plasmas require coils that will produce plasmas satisfying a set of physics goals, provide experimental flexibility, and be practical to construct. In the course of designing a flexible coil set for the National Compact Stellarator Experiment, we have made several innovations that may be useful in future stellarator design efforts. These include: the use of Singular Value Decomposition methods for obtaining families of smooth current potentials on distant coil winding surfaces from which low current density solutions may be identified; the use of a Control Matrix Method for identifying which few of the many detailed elements of the stellarator boundary must be targeted if a coil set is to provide fields to control the essential physics of the plasma; the use of Genetic Algorithms for choosing an optimal set of discrete coils from a continuum of potential contours; the evaluation of alternate coil topologies for balancing the tradeoff between physics objective and engineering constraints; the development of a new coil optimization code for designing modular coils, and the identification of a 'natural' basis for describing current sheet distributions. (author)

Development work for the Japanese LCT coil and its design and construction

International Nuclear Information System (INIS)

Shimamoto, Susumu; Ando, Toshinari; Tsuji, Hiroshi; Yasukochi, Ko

1984-01-01

This paper describes design, verification tests, and construction of the Japanese test coil for the Large Coil Task (LCT). Japan Atomic Energy Research Institute (JAERI) signed on the LCT international agreement under the International Energy Agency (IEA) in 1978, and since then JAERI has been working to develop the Japanese LCT coil to explore the problems of design and construction of tokamak toroidal coil. Based on the common requirements of the LCT, the Japanese LCT coil was designed to be a pool-cooled NbTi fully-stabilized coil whose operating current is 10,220 A at 8 T. Through research and development of the Japanese LCT coil, new advances in the super-conducting coil technology were obtained, such as mechanically and chemically treated conductor surface that has high heat transfer about four times as much as usual ones, nitrogen-strengthened stainless steel that has the yield strength twice as much as usual stainless steel, NbTi filaments those have the critical current density twice as much as those before LCT, and so on. These advances have enabled to construct the Japanese LCT coil and it was completed in the spring of 1982. During the construction of the coil, new fabrication techniques were obtained to wind large current conductor into a mechanically rigid coil and thus to construct a totally stable large coil. (author)

Study on usage of fluorocarbon for toroidal field coil cooling

International Nuclear Information System (INIS)

Miyata, Hiroshi; Arai, Takashi

1998-09-01

In JT-60 machine, usage of fluorocarbon as an alternate coolant to a cooling channel of toroidal field coil (TF coil) in which a crack was detected is investigated. Fluorinert (a registered trademark of 3M) liquid which is one of fluorocarbon was reviewed, and liquid 'FC-43' was found as an appropriate one for TF coils cooling because of its physical properties about boiling point and thermal capacity. Fortunately, Fluorinert does not have impact on the greenhouse effect for the earth under the temperature of its boiling point. And thermal analysis shows that the cooling effectiveness obtained with liquid 'FC-43' for TF coils is rather well. Moreover, corrosion tests were carried out between liquid 'FC-43' and materials used in JT-60 by considering deterioration of TF coils. The test results demonstrate that there is no problem in applying liquid 'FC-43' as a coolant to cooling channel of TF coils. Results obtained above conclude that usage of fluorocarbon is one of the effective means to perform further experiments in JT-60. (author)

Resistive toroidal-field coils for tokamak reactors

International Nuclear Information System (INIS)

Kalnavarns, J.; Jassby, D.L.

1980-11-01

This paper analyzes the optimization of the geometry of resistive TF coils of rectangular bore for tokamak fusion test reactors and practical neutron generators. In examining the trade-offs between geometric parameters and magnetic field for reactors giving a specified neutron wall loading, either the resistive power loss or the lifetime coil cost can be minimized. Aspects of cooling, magnetic stress, and construction are addressed for several reference designs. Bending moment distributions in closed form have been derived for rectangular coils on the basis of the theory of rigid frames. Candidate methods of fabrication and of implementing demountable joints are summarized

Plasmodium vivax antigen discovery based on alpha-helical coiled coil protein motif

DEFF Research Database (Denmark)

Céspedes, Nora; Habel, Catherine; Lopez-Perez, Mary

2014-01-01

Protein α-helical coiled coil structures that elicit antibody responses, which block critical functions of medically important microorganisms, represent a means for vaccine development. By using bioinformatics algorithms, a total of 50 antigens with α-helical coiled coil motifs orthologous to Pla...

Status of the GA/MCA 12 Tesla Coil Development Program

International Nuclear Information System (INIS)

Alcorn, J.S.; Purcell, J.R.; Chen, W.Y.; Hsu, Y.H.

1980-09-01

The current status of the Team One effort of the DOE/OFE/D and T 12 Tesla Coil Development Program is presented. Subatmospheric, helium bath cooled, NbTiTa alloy is employed for the test coil, and ETF TF-coil concept. General Atomic is the Team One leader, with Magnetic Corporation of American as industrial subcontractor

NCSX Trim Coil Design

International Nuclear Information System (INIS)

Kalish, M.; Brooks, A.; Rushinski, J.; Upcavage, R.

2009-01-01

The National Compact Stellarator Experiment (NCSX) was being constructed at the Princeton Plasma Physics Laboratory in partnership with Oak Ridge National Laboratory before work was stopped in 2008. The objective of this experiment was to develop the stellarator concept and evaluate it's potential as a model for future fusion power plants. Stellarator design requires very precisely positioned Modular Coils of complex shape to form 3D plasmas. In the design of NCSX, Trim Coils were required to compensate for both the positioning of the coils during assembly and the fabrication tolerances of the Modular Coils. Use of the Trim Coils allowed for larger tolerances increasing ease of assembly and decreasing overall cost. A set of Trim coils was developed to suppress the toroidal flux in island regions due to misalignment, magnetic materials, and eddy currents. The requirement imposed upon the design forced the toroidal flux in island regions below 10% of the total toroidal flux in the plasma. An analysis was first performed to evaluate candidate Trim Coil configurations iterating both the size, number, and position of the coils. The design was optimized considering both performance and cost while staying within the tight restraints presented by the space limited geometry. The final design of the Trim Coils incorporated a 48 Coil top bottom symmetric set. Fabrication costs were minimized by having only two coil types and using a planar conventional design with off the shelf commercial conductor. The Trim Coil design incorporated supports made from simple structural shapes assembled together in a way which allowed for adjustment as well as accommodation for the tolerance build up on the mating surfaces. This paper will summarize the analysis that led to the optimization of the Trim Coils set, the trim coil mechanical design, thermal and stress analysis, and the design of the supporting Trim Coil structure

Computer-based data acquisition system in the Large Coil Test Facility

International Nuclear Information System (INIS)

Gould, S.S.; Layman, L.R.; Million, D.L.

1983-01-01

The utilization of computers for data acquisition and control is of paramount importance on large-scale fusion experiments because they feature the ability to acquire data from a large number of sensors at various sample rates and provide for flexible data interpretation, presentation, reduction, and analysis. In the Large Coil Test Facility (LCTF) a Digital Equipment Corporation (DEC) PDP-11/60 host computer with the DEC RSX-11M operating system coordinates the activities of five DEC LSI-11/23 front-end processors (FEPs) via direct memory access (DMA) communication links. This provides host control of scheduled data acquisition and FEP event-triggered data collection tasks. Four of the five FEPs have no operating system

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

Energy Technology Data Exchange (ETDEWEB)

Peter K. F. Hwang

2007-10-22

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.

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

International Nuclear Information System (INIS)

Hwang, Peter K.F.

2007-01-01

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-inch 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.

Composite coils for toroidal field coils and method of using same

International Nuclear Information System (INIS)

Perkins, R. G.; Trujillo, S. M.

1985-01-01

A composite toroidal field (TF) generating means consisting of segmented magnetic coil windings is disclosed. Each coil winding of the TF generating means consists of a copper or copper alloy conductor segment and an aluminum or aluminum alloy conductor segment. The conductor segments are joined at a high strength, low electrical resistance joint and the joint may either be a mechanical or metallurgical one. The use of the aluminum or aluminum alloy conductor segments improves the neutron economy of the reactor with which the TF coil is associated and reduces TF coil nuclear heating and heating gradients, and activation in the TF coils

Outcomes with single-coil versus dual-coil implantable cardioverter defibrillators: a meta-analysis.

Science.gov (United States)

Sunderland, Nicholas; Kaura, Amit; Murgatroyd, Francis; Dhillon, Para; Scott, Paul A

2018-03-01

Dual-coil implantable cardioverter defibrillator (ICD) leads have traditionally been used over single-coil leads due to concerns regarding high defibrillation thresholds (DFT) and consequent poor shock efficacy. However, accumulating evidence suggests that this position may be unfounded and that dual-coil leads may also be associated with higher complication rates during lead extraction. This meta-analysis collates data comparing dual- and single-coil ICD leads. Electronic databases were systematically searched for randomized controlled trials (RCT) and non-randomized studies comparing single-coil and dual-coil leads. The mean differences in DFT and summary estimates of the odds-ratio (OR) for first-shock efficacy and the hazard-ratio (HR) for all-cause mortality were calculated using random effects models. Eighteen studies including a total of 138,124 patients were identified. Dual-coil leads were associated with a lower DFT compared to single coil leads (mean difference -0.83J; 95% confidence interval [CI] -1.39--0.27; P = 0.004). There was no difference in the first-shock success rate with dual-coil compared to single-coil leads (OR 0.74; 95%CI 0.45-1.21; P=0.22). There was a significantly lower risk of all-cause mortality associated with single-coil leads (HR 0.91; 95%CI 0.86-0.95; P dual-coil leads. The mortality benefit with single-coil leads most likely represents patient selection bias. Given the increased risk and complexity of extracting dual-coil leads, centres should strongly consider single-coil ICD leads as the lead of choice for routine new left-sided ICD implants. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Finite element coiled cochlea model

Science.gov (United States)

Isailovic, Velibor; Nikolic, Milica; Milosevic, Zarko; Saveljic, Igor; Nikolic, Dalibor; Radovic, Milos; Filipović, Nenad

2015-12-01

Cochlea is important part of the hearing system, and thanks to special structure converts external sound waves into neural impulses which go to the brain. Shape of the cochlea is like snail, so geometry of the cochlea model is complex. The simplified cochlea coiled model was developed using finite element method inside SIFEM FP7 project. Software application is created on the way that user can prescribe set of the parameters for spiral cochlea, as well as material properties and boundary conditions to the model. Several mathematical models were tested. The acoustic wave equation for describing fluid in the cochlea chambers - scala vestibuli and scala timpani, and Newtonian dynamics for describing vibrations of the basilar membrane are used. The mechanical behavior of the coiled cochlea was analyzed and the third chamber, scala media, was not modeled because it does not have a significant impact on the mechanical vibrations of the basilar membrane. The obtained results are in good agreement with experimental measurements. Future work is needed for more realistic geometry model. Coiled model of the cochlea was created and results are compared with initial simplified coiled model of the cochlea.

Water cooling coil

Energy Technology Data Exchange (ETDEWEB)

Suzuki, S; Ito, Y; Kazawa, Y

1975-02-05

Object: To provide a water cooling coil in a toroidal nuclear fusion device, in which coil is formed into a small-size in section so as not to increase dimensions, weight or the like of machineries including the coil. Structure: A conductor arranged as an outermost layer of a multiple-wind water cooling coil comprises a hollow conductor, which is directly cooled by fluid, and as a consequence, a solid conductor disposed interiorly thereof is cooled indirectly.

The Normal Zone Propagation in ATLAS B00 Model Coil

NARCIS (Netherlands)

Boxman, E.W.; Dudarev, A.V.; ten Kate, Herman H.J.

2002-01-01

The B00 model coil has been successfully tested in the ATLAS Magnet Test Facility at CERN. The coil consists of two double pancakes wound with aluminum stabilized cables of the barrel- and end-cap toroids conductors for the ATLAS detector. The magnet current is applied up to 24 kA and quenches are

HydroSoft coil versus HydroCoil for endovascular aneurysm occlusion study: A single center experience

International Nuclear Information System (INIS)

Guo Xinbin; Fan Yimu; Zhang Jianning

2011-01-01

Background and purpose: The HydroCoil Embolic System (HES) was developed to reduce recurrences of aneurysms relative to platinum coils. But the HydroCoil Embolic System was characterized with many limitations. The manufacturer had recognized the challenge and recently a new design of hydrogel-coated coil-HydroSoft has become available in the market as the new generation HydroCoil. We reported our initial experience using HydroSoft coil versus HydroCoil in our center. Methods: 75 aneurysms embolized primarily using HydroSoft Coils from July 2008 to May 2009 were compared with 66 volume- and shape-matched aneurysms treated with HydroCoils from March 2006 to August 2008. Outcome measures included length and number of coils used, contrast volume, and length of hospital stay. During embolization, a stable framework was first established with bare coils, and hydrogel-coated coils were used subsequently to increase the packing density. Follow-up angiographic results 6 months after treatment were evaluated among some of the patients. Results: Successful coil embolization was achieved in all patients. There were no differences in average total coil length used per aneurysm. There were no differences in length of hospital stay and packing density. HydroSoft coils were more suitable using as the finishing or final coil. HydroSoft coil decreased the procedure-related retreated rates, and aneurysm packing was finished with soft, flexible HydroSoft coil and decreased the neck remnant rates. Follow-up angiography in HydroSoft-treated patients at 6 months revealed aneurysm stability without significant residual neck. Conclusions: HydroSoft coil allowed us to deploy coated coils with good packing density. A slight expansion of these coils at the neck can be expected to reduce neck remnant and potentially inhibit recurrence.

Superconducting coil manufacturing method for low current dc beam line magnets

International Nuclear Information System (INIS)

Satti, J.A.

1977-01-01

A method of manufacturing superconducting multipole coils for 40 to 50 kG dc beam line magnets with low current is described. Small coils were built and tested successfully to short sample characteristics. The coils did not train after the first cooldown. The coils are porous and well cooled to cope with mechanical instability and energy deposited in the coil from the beam particles. The coils are wound with insulated strand cable. The cable is shaped rectangularly for winding simplicity and good tolerances. After the coil is wound, the insulated strands are electrically connected in series. This reduces the operating current and, most important, improves the coil quench propagation due to heat conduction of one strand adjacent to the other. A well distributed quench allows the magnet energy to distribute more uniformly to the copper in the superconductor wire, giving self-protected coils. A one-meter long, 43 kG, 6-inch bore tube superconducting dipole is now being fabricated. The porous coil design and coil winding methods are discussed

Development and fabrication of a Bi-2223 racetrack coil for generator applications

International Nuclear Information System (INIS)

Herd, K.G.; Salasoo, L.; Laskaris, E.T.; Ranze, R.A.; King, C.G.

1996-01-01

The development and fabrication of a layer-wound, epoxy-impregnated Bi-2223 high-temperature superconducting (HTS) racetrack coil which generates 40,000 ampere-turns of magnetomotive force (MMF) at 25 K is described. The coil was wound using Ag-sheathed Bi-2223 tape conductor laminated with copper foils for strength enhancement and insulated using a paper-wrap method. After epoxy impregnation, the coil was tested over a range of 16--25 K in a vacuum dewar using a closed-cycle helium refrigeration system. Descriptions of the tape lamination and insulation processing, the coil winding and impregnation, and the experimental test setup are given

ER@CEBAF: A test of 5-pass energy recovery at CEBAF

Energy Technology Data Exchange (ETDEWEB)

Bogacz, S. A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Dubbe, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hutton, A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Michalski, T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Pilat, F. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Y. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Satogata, T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Spata, M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tiefenback, M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hao, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Korysko, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-06-06

Jefferson Lab personnel have broad expertise in the design, commissioning, and operation of multiple energy recovery linacs (ERLs): the CEBAF Front-End Test (early 1990s), CEBAF-ER (2003), the IR Free Electron Laser (FEL) Demo, the IR FEL Upgrade, and the UV FEL Driver (1997-2014). Continued development of this core competency has led to this collaborative proposal to explore the forefronts of ERL technology at high energy in a unique expansion of CEBAF capability to a 5-pass ERL with negligible switchover time and programmatic impact to the CEBAF physics program. Such a capability would enable world-class studies of open issues in high-energy ERL beam dynamics that are relevant to future facilities such as electron-ion colliders (EICs). This proposal requests support from the CEBAF Program Advisory Committee to seek funding for hardware installation, and a prospective 12 days of beam time circa Fall 2018 for commissioning this high-energy multi-pass ERL experiment in CEBAF.

Experimental and theoretical investigation of mechanical disturbances in epoxy-impregnated superconducting coils

International Nuclear Information System (INIS)

Iwasa, Y.; Bobrov, E.S.; Tsukamoto, O.; Takaghi, T.; Fujita, H.; Massachusetts Inst. of Tech., Cambridge

1985-01-01

The theoretical correlation between shear stress and epoxy resin fracture developed in an earlier paper was verified experimentally using a series of epoxy-impregnated, thin-walled superconducting test coils. In test coils with both ends rigidly clamped, cracks occurred as transport current was increased; during a training sequence the test was terminated by a premature quench. Using acoustic emission and voltage signals, each premature quench was linked directly to a crack occurring near one of the ends. Test coils which had both ends unsupported, giving the winding freedom to expand radially, did not experience epoxy fracture and showed no premature quenches. (author)

Automated de novo phasing and model building of coiled-coil proteins.

Science.gov (United States)

Rämisch, Sebastian; Lizatović, Robert; André, Ingemar

2015-03-01

Models generated by de novo structure prediction can be very useful starting points for molecular replacement for systems where suitable structural homologues cannot be readily identified. Protein-protein complexes and de novo-designed proteins are examples of systems that can be challenging to phase. In this study, the potential of de novo models of protein complexes for use as starting points for molecular replacement is investigated. The approach is demonstrated using homomeric coiled-coil proteins, which are excellent model systems for oligomeric systems. Despite the stereotypical fold of coiled coils, initial phase estimation can be difficult and many structures have to be solved with experimental phasing. A method was developed for automatic structure determination of homomeric coiled coils from X-ray diffraction data. In a benchmark set of 24 coiled coils, ranging from dimers to pentamers with resolutions down to 2.5 Å, 22 systems were automatically solved, 11 of which had previously been solved by experimental phasing. The generated models contained 71-103% of the residues present in the deposited structures, had the correct sequence and had free R values that deviated on average by 0.01 from those of the respective reference structures. The electron-density maps were of sufficient quality that only minor manual editing was necessary to produce final structures. The method, named CCsolve, combines methods for de novo structure prediction, initial phase estimation and automated model building into one pipeline. CCsolve is robust against errors in the initial models and can readily be modified to make use of alternative crystallographic software. The results demonstrate the feasibility of de novo phasing of protein-protein complexes, an approach that could also be employed for other small systems beyond coiled coils.

Dual levitated coils for antihydrogen production

Science.gov (United States)

Wofford, J. D.; Ordonez, C. A.

2013-04-01

Two coaxial superconducting magnetic coils that carry currents in the same direction and that are simultaneously levitated may serve for antihydrogen plasma confinement. The configuration may be suitable for use by a collaboration at the CERN Antiproton Decelerator facility to test fundamental symmetries between the properties of hydrogen and antihydrogen. Nested Penning traps are currently used to confine recombining antihydrogen plasma. Symmetry studies require the production of sufficiently cold antihydrogen. However, plasma drifts within nested Penning traps can increase the kinetic energy of antiprotons that form antihydrogen atoms. Dual levitated coils may serve to confine relatively large, cold, dense non-drifting recombining antihydrogen plasmas. A minimum-B magnetic field that is produced by the coils could provide for atom trapping. A toroidal plasma is confined between the coils. High density plasmas may be possible, by allowing plasma pressure to balance mechanical pressure to keep the coils apart. Progress is reported on theoretical and experimental efforts. The theoretical effort includes the development of a classical trajectory Monte Carlo simulation of confinement. The experimental effort includes levitation of a NdFeB permanent ring magnet, which produces a magnetic field that is qualitatively similar to the field that would be produced by the two coaxial superconducting magnetic coils. Liquid-nitrogen-cooled Bi-2223 high-temperature-superconducting components, with a critical temperature of 108 K, were used to levitate the ring magnet. An issue concerning keeping the plane of the levitated ring horizontal is discussed.

Development and test of Nb3sn cos-theta coils made of high-jc rrp strands

Energy Technology Data Exchange (ETDEWEB)

Bossert, R.; Ambrosio, G.; Andreev, N.; Barzi, E.; Carcagno, R.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Novitski, I.; Pischalnikov, Yu.; Sylvester, C.; Tartaglia, M.; Turrioni, D.; Yamada, R.; Zlobin, A.V.; /Fermilab

2005-10-01

A series of 1-m long Nb3Sn dipole magnets have been built at Fermilab in an attempt to refine the wind-and-react technology for Nb{sub 3}Sn conductor. Models have been made with MJR and PIT strand with varying degrees of success. Subsequently two new dipole ''mirror'' magnets based on RRP Nb{sub 3}Sn coils were constructed and tested. This paper describes the design, fabrication and test results of those magnets.

Fabrication of seamless calandria tubes by cold pilgering route using 3-pass and 2-pass schedules

Science.gov (United States)

Saibaba, N.

2008-12-01

Calandria tube is a large diameter, extremely thin walled zirconium alloy tube which has diameter to wall thickness ratio as high as 90-95. Such tubes are conventionally produced by the 'welded route', which involves extrusion of slabs followed by a series of hot and cold rolling passes, intermediate anneals, press forming of sheets into circular shape and closing the gap by TIG welding. Though pilgering is a well established process for the fabrication of seamless tubes, production of extremely thin walled tubes offers several challenges during pilgering. Nuclear fuel complex (NFC), Hyderabad, has successfully developed a process for the production of Zircaloy-4 calandria tubes by adopting the 'seamless route' which involves hot extrusion of mother blanks followed by three-pass pilgering or two-pass pilgering schedules. This paper deals with standardization of the seamless route processes for fabrication of calandria tubes, comparison between the tubes produced by 2-pass and 3-pass pilgering schedules, role of ultrasonic test charts for control of process parameters, development of new testing methods for burst testing and other properties.

Fabrication of seamless calandria tubes by cold pilgering route using 3-pass and 2-pass schedules

International Nuclear Information System (INIS)

Saibaba, N.

2008-01-01

Calandria tube is a large diameter, extremely thin walled zirconium alloy tube which has diameter to wall thickness ratio as high as 90-95. Such tubes are conventionally produced by the 'welded route', which involves extrusion of slabs followed by a series of hot and cold rolling passes, intermediate anneals, press forming of sheets into circular shape and closing the gap by TIG welding. Though pilgering is a well established process for the fabrication of seamless tubes, production of extremely thin walled tubes offers several challenges during pilgering. Nuclear fuel complex (NFC), Hyderabad, has successfully developed a process for the production of Zircaloy-4 calandria tubes by adopting the 'seamless route' which involves hot extrusion of mother blanks followed by three-pass pilgering or two-pass pilgering schedules. This paper deals with standardization of the seamless route processes for fabrication of calandria tubes, comparison between the tubes produced by 2-pass and 3-pass pilgering schedules, role of ultrasonic test charts for control of process parameters, development of new testing methods for burst testing and other properties

Conception of Brownian coil

OpenAIRE

Zhang, Jiayuan

2018-01-01

This article proposes a conception of Brownian coil. Brownian coil is a tiny coil with the same size of pollen. Once immersed into designed magnetic field and liquid, the coil will be moved and deformed macroscopically, due to the microscopic thermodynamic molecular collisions. Such deformation and movement will change the magnetic flux through the coil, by which an ElectroMotive Force (EMF) is produced. In this work, Brownian heat exchanger and Brownian generator are further designed to tran...

Mechanical behavior of the ATLAS B0 model coil

CERN Document Server

Foussat, A; Acerbi, E; Alessandria, F; Berthier, R; Broggi, F; Daël, A; Dudarev, A; Mayri, C; Miele, P; Reytier, M; Rossi, L; Sorbi, M; Sun, Z; ten Kate, H H J; Vanenkov, I; Volpini, G

2002-01-01

The ATLAS B0 model coil has been developed and constructed to verify the design parameters and the manufacture techniques of the Barrel Toroid coils (BT) that are under construction for the ATLAS Detector. Essential for successful operation is the mechanical behavior of the superconducting coil and its support structure. In the ATLAS magnet test facility, a magnetic mirror is used to reproduce in the model coil the electromagnetic forces of the BT coils when assembled in the final Barrel Toroid magnet system. The model coil is extensively equipped with mechanical instrumentation to monitor stresses and force levels as well as contraction during a cooling down and excitation up to nominal current. The installed set up of strain gauges, position sensors and capacitive force transducers is presented. Moreover the first mechanical results in terms of expected main stress, strain and deformation values are presented based on detailed mechanical analysis of the design. (7 refs).

Historical review: another 50th anniversary--new periodicities in coiled coils.

Science.gov (United States)

Gruber, Markus; Lupas, Andrei N

2003-12-01

In 1953, Francis Crick and Linus Pauling both proposed models of supercoiled alpha helices ('coiled coils') for the structure of keratin. These were the first attempts at modelling the tertiary structure of a protein. Crick emphasized the packing mode of the side-chains ('knobs-into-holes'), which required a periodicity of seven residues over two helical turns (7/2) and a supercoil in the opposite sense of the constituent helices. By contrast, Pauling envisaged a broader set of periodicities (4/1, 7/2, 18/5, 15/4, 11/3) and supercoils of both senses. Crick's model became canonical and the 'heptad repeat' essentially synonymous with coiled coils, but 50 years later new crystal structures and protein sequences show that the less common periodicities envisaged by Pauling also occur in coiled coils, adding a variant packing mode ('knobs-to-knobs') to the standard model. Pauling's laboratory notebooks suggest that he searched unsuccessfully for this packing mode in 1953.

Impedance of curved rectangular spiral coils around a conductive cylinder

Science.gov (United States)

Burke, S. K.; Ditchburn, R. J.; Theodoulidis, T. P.

2008-07-01

Eddy-current induction due to a thin conformable coil wrapped around a long conductive cylinder is examined using a second-order vector potential formalism. Compact closed-form expressions are derived for the self- and mutual impedances of curved rectangular spiral coils (i) in free space and (ii) when wrapped around the surface of the cylindrical rod. The validity of these expressions was tested against the results of a systematic series of experiments using a cylindrical Al-alloy rod and conformable coils manufactured using flexible printed-circuit-board technology. The theoretical expressions were in very good agreement with the experimental measurements. The significance of the results for eddy-current nondestructive inspection using flexible coils and flexible coil arrays is discussed.

Coiled-Coil Proteins Facilitated the Functional Expansion of the Centrosome

Science.gov (United States)

Kuhn, Michael; Hyman, Anthony A.; Beyer, Andreas

2014-01-01

Repurposing existing proteins for new cellular functions is recognized as a main mechanism of evolutionary innovation, but its role in organelle evolution is unclear. Here, we explore the mechanisms that led to the evolution of the centrosome, an ancestral eukaryotic organelle that expanded its functional repertoire through the course of evolution. We developed a refined sequence alignment technique that is more sensitive to coiled coil proteins, which are abundant in the centrosome. For proteins with high coiled-coil content, our algorithm identified 17% more reciprocal best hits than BLAST. Analyzing 108 eukaryotic genomes, we traced the evolutionary history of centrosome proteins. In order to assess how these proteins formed the centrosome and adopted new functions, we computationally emulated evolution by iteratively removing the most recently evolved proteins from the centrosomal protein interaction network. Coiled-coil proteins that first appeared in the animal–fungi ancestor act as scaffolds and recruit ancestral eukaryotic proteins such as kinases and phosphatases to the centrosome. This process created a signaling hub that is crucial for multicellular development. Our results demonstrate how ancient proteins can be co-opted to different cellular localizations, thereby becoming involved in novel functions. PMID:24901223

CCBuilder 2.0: Powerful and accessible coiled-coil modeling.

Science.gov (United States)

Wood, Christopher W; Woolfson, Derek N

2018-01-01

The increased availability of user-friendly and accessible computational tools for biomolecular modeling would expand the reach and application of biomolecular engineering and design. For protein modeling, one key challenge is to reduce the complexities of 3D protein folds to sets of parametric equations that nonetheless capture the salient features of these structures accurately. At present, this is possible for a subset of proteins, namely, repeat proteins. The α-helical coiled coil provides one such example, which represents ≈ 3-5% of all known protein-encoding regions of DNA. Coiled coils are bundles of α helices that can be described by a small set of structural parameters. Here we describe how this parametric description can be implemented in an easy-to-use web application, called CCBuilder 2.0, for modeling and optimizing both α-helical coiled coils and polyproline-based collagen triple helices. This has many applications from providing models to aid molecular replacement for X-ray crystallography, in silico model building and engineering of natural and designed protein assemblies, and through to the creation of completely de novo "dark matter" protein structures. CCBuilder 2.0 is available as a web-based application, the code for which is open-source and can be downloaded freely. http://coiledcoils.chm.bris.ac.uk/ccbuilder2. We have created CCBuilder 2.0, an easy to use web-based application that can model structures for a whole class of proteins, the α-helical coiled coil, which is estimated to account for 3-5% of all proteins in nature. CCBuilder 2.0 will be of use to a large number of protein scientists engaged in fundamental studies, such as protein structure determination, through to more-applied research including designing and engineering novel proteins that have potential applications in biotechnology. © 2017 The Authors Protein Science published by Wiley Periodicals, Inc. on behalf of The Protein Society.

DESIGN, FABRICATION AND TEST OF THE REACT AND WIND, NB(3)SN, LDX FLOATING COIL CONDUCTOR

International Nuclear Information System (INIS)

SMITH, B.A.; MICHAEL, P.C.; MINERVINI, J.V.; TAKAYASU, M.; SCHULTZ, J.H.; GREGORY, E.; PYON, T.; SAMPSON, W.B.; GHOSH, A.; SCANLAN, R.

2000-01-01

The Levitated Dipole Experiment (LDX) is a novel approach for studying magnetic confinement of a fusion plasma. In this approach, a superconducting ring coil is magnetically levitated for up to 8 hours a day in the center of a 5 meter diameter vacuum vessel. The levitated coil, with on-board helium supply, is called the gloating Coil (F-Coil). Although the maximum field at the coil is only 5.3 tesla, a react-and-wind Nb 3 Sn conductor was selected because the relatively high critical temperature will enable the coil to remain levitated while it warms from 5 K to 10 K. Since pre-reacted Nb 3 Sn tape is no longer commercially available, a composite conductor was designed that contains an 18 strand Nb 3 Sn Rutherford cable. The cable was reacted and then soldered into a structural copper channel that completes the conductor and also provides quench protection. The strain state of the cable was continuously controlled during fabrication steps such as: soldering into the copper channel, spooling, and coil winding, to prevent degradation of the critical current. Measurements of strand and cable critical currents are reported, as well as estimates of the effect of fabrication, winding and operating strains on critical current

HydroCoil as an adjuvant to bare platinum coil treatment of 100 cerebral aneurysms

International Nuclear Information System (INIS)

Fanning, Noel F.; Berentei, Zsolt; Brennan, Paul R.; Thornton, John

2007-01-01

Introduction The overall safety of the HydroCoil, an expansile hybrid hydrogel-platinum coil, is unknown. We report a prospective observational study of our first 100 cerebral aneurysms treated with HydroCoils, focusing on safety and initial efficacy.Methods Indications, procedural complications, clinical and angiographic outcomes were recorded. Packing density, number of coils deployed and angiographic results were compared with those in a matched control group of 100 aneurysms treated solely with bare platinum coils. HydroCoil complication rates were compared to bare platinum coil rates at our institution and in published series. Results Adjuvant HydroCoil treatment led to increased mean percentage aneurysm filling compared to controls (50 ± 21% versus 27 ± 13%, P < 0.001). Immediate posttreatment angiographic results showed significantly (P < 0.001) more complete occlusions and fewer incomplete (<95%) occlusions compared to controls. Intermediate follow-up angiograms (median 7.5 months) in 63 aneurysms showed a trend towards fewer incomplete occlusions with HydroCoil treatment. There were significantly fewer major recurrences with HydroCoil treatment compared to the control treatment (9.5% versus 22.6%, P 0.046). In the adjuvant HydroCoil group, major recurrent aneurysms had significantly less percentage volume packing with HydroCoils than non-recurrent aneurysms (50.3 ± 5.0% versus 65.3 ± 18.0%, P = 0.04). There was a 12% procedural complication rate, 6% procedural morbidity and 1% mortality rate, similar to institutional and reported bare platinum coil complication rates.Conclusion HydroCoils can be safely deployed with a similar complication rate to bare platinum coils. They result in improved aneurysm filling. Intermediate follow-up angiography showed significantly fewer major recurrences. Long-term follow-up is required to confirm initial improved stability. (orig.)

Quench performance of a 4-m long Nb3Sn shell-type dipole coil

International Nuclear Information System (INIS)

Chlachidze, G.; Ambrosio, G.; Andreev, N.; Barzi, E.; Bossert, R.; Carcagno, R.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.

2008-01-01

Fermilab has finished the first phase of Nb 3 Sn technology scale up by testing 2-m and 4-m long shell-type dipole coils in a 'magnetic mirror' configuration. The 2-m long coil, made of Powder-in-Tube (PIT) Nb 3 Sn strand, reached its short sample limit at a field level of 10 T. The 4-m long coil, made of advanced Nb 3 Sn strand based on the Restack Rod Process (RRP) of 108/127 design, has been recently fabricated and tested. Coil test results at 4.5 K and 2.2 K are reported and discussed

Performance of trim coils made by a novel method

International Nuclear Information System (INIS)

Wanderer, P.; Anerella, M.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A.; Goodzeit, C.; Greene, A.; Gupta, R.; Herrera, J.; Kahn, S.; Kelly, E.; Meade, A.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E.P.; Sampson, W.; Shutt, R.; Skaritka, J.; Thompson, P.; Willen, E.

1991-01-01

A precision, automated method of manufacturing trim coils based on printed circuit technology has been developed. Excellent quench performance and increased radiation resistance have been achieved in recently-tested models of sextupole trim coils developed for operation inside 40 mm-aperture SSC Main Collider dipoles. 6 refs., 2 figs

TF insert experiment log book. 2nd Experiment of CS model coil

International Nuclear Information System (INIS)

Sugimoto, Makoto; Isono, Takaaki; Matsui, Kunihiro

2001-12-01

The cool down of CS model coil and TF insert was started on August 20, 2001. It took almost one month and immediately started coil charge since September 17, 2001. The charge test of TF insert and CS model coil was completed on October 19, 2001. In this campaign, total shot numbers were 88 and the size of the data file in the DAS (Data Acquisition System) was about 4 GB. This report is a database that consists of the log list and the log sheets of every shot. This is an experiment logbook for 2nd experiment of CS model coil and TF insert for charge test. (author)

Testing cold protection according to EN ISO 20344: is there any professional footwear that does not pass?

Science.gov (United States)

Kuklane, Kalev; Ueno, Satoru; Sawada, Shin-Ichi; Holmér, Ingvar

2009-01-01

The present Comité Européen de Normalisation (CEN) and International Organization for Standardization (ISO) standards for safety, protective and occupational footwear EN ISO 20344-20347 classify footwear as cold protective by a pass/fail test where the limits are set for an allowed 10 degrees C temperature drop inside the footwear during 30 min at a temperature gradient of approximately 40 degrees C. It is questionable if a simple pass/fail test of this kind provides approved footwear that really protects the feet from cooling in exposures ranging from temperatures at +18 degrees C to as low as or even lower than -50 degrees C. This study selected for testing some professional footwear that could certainly not be considered as cold protective. Some footwear that could be used in cold was selected with as low insulation as the not cold-intended footwear. Also, a boot intended for cold was selected to be tested according to a modified standard at a temperature gradient of 70 degrees C. The footwear selection was based on insulation measurements with a thermal foot model. All footwear did pass the test. Although it is clear for the user that a sandal, a mesh shoe or a thin textile shoe is not cold protective, it is not as clear that an item of safety footwear, that has as low insulation as those mentioned above, could be classified as cold protective according to the present standards. Because of this, the user might have a deceptive feeling of safety and may be exposed to higher risks. As practically all professional footwear may pass this cold test, then the method/requirements should be radically changed or such a test should be removed from the standards.

A 1.5 MJ cryostatic stable superconducting ohmic-heating coil

International Nuclear Information System (INIS)

Wang, S.-T.; Kim, S.H.; Praeg, W.F.; Krieger, C.I.

1978-01-01

As early as FY 1975, ANL had recognized the clear advantage of a superconducting ohmic-heating (OH) coil and proposed a five-year pulsed coil and power supply development program to ERDA. With modest funding made available by ERDA in FY 1977 and the use of substantial equipment inventory at ANL, a small but agressive development program was advanced to the construction of a 1.5 MJ model coil. The principle objective in building the 1.5 MJ ac coil is to demonstrate ac cryostability of a large coil with a dB/dt ranging from 2 T/s up to 14 T/s. The results of basic cable development and tests will be described. The design and construction of a prototype 1.5 MJ cryostable pulsed coil and its nonmetallic cryostat will be presented. (author)

Dual coil ignition system

Energy Technology Data Exchange (ETDEWEB)

Huberts, Garlan J.; Qu, Qiuping; Czekala, Michael Damian

2017-03-28

A dual coil ignition system is provided. The dual coil ignition system includes a first inductive ignition coil including a first primary winding and a first secondary winding, and a second inductive ignition coil including a second primary winding and a second secondary winding, the second secondary winding connected in series to the first secondary winding. The dual coil ignition system further includes a diode network including a first diode and a second diode connected between the first secondary winding and the second secondary winding.

'Investigation on the heat dissipation characteristics of electromagnetic coil for high temperature applications

International Nuclear Information System (INIS)

Saran, Shiv Raj; Taly, Y. K.; Mahapatra, U.; Chandraker, D.K.

2011-01-01

Full text: Function of electromagnetic coil is to generate magnetic flux for electromechanical devices like linear actuator, motor etc. Electromagnetic coils are used in the Advanced Magnetic Jack Mechanism (AMJM) and In-Vessel Control Rod Drive Mechanism (IV CRDM) to control the motion of the rod in the reactor. This paper describes results of the thermal analysis with several candidate materials to design the electromagnetic coil for desired high temperature (∼ 350 deg C) service life by using well established software to study the thermal design for in-vessel control rod drive mechanism. A test model of electromagnetic coil is fabricated and tested at room temperature (30 deg C). The measured temperatures from the test model at selected locations (along radial and axial direction) have been used to validate the design methodology by finite element analysis. Various candidate materials (Ceramic fiber, glass fiber, mineral insulated conductors) for electromagnetic coil have been analyzed to investigate the suitability for high temperature (∼ 350 deg C) applications. This study will be useful for designing electromagnetic coils for in-vessel control rod drive mechanism

Coil Migration through a Neuroform 3 Stent during Endovascular Coiling. A Case Report.

LENUS (Irish Health Repository)

O'Hare, A

2009-07-29

Summary: A 43-year-old woman attended for stent assisted coiling. A Neuroform 30 x 4.5 mm stent had been successfully placed over the left periophthalmic aneurysm. During the coiling the first coil migrated through the crowns in the stent, lodging at the MCA bifurcation. We believe that the coil herniated through the overlying stent due to the carotid siphon curvature and the open cell design. Furthermore the distal markers of the stent impeded coil extraction with a MERCI device.

NCSX Toroidal Field Coil Design

International Nuclear Information System (INIS)

Kalish M; Rushinski J; Myatt L; Brooks A; Dahlgren F; Chrzanowski J; Reiersen W; Freudenberg K.

2005-01-01

The National Compact Stellarator Experiment (NCSX) is an experimental device whose design and construction is underway at the Department of Energy's Princeton Plasma Physics Laboratory (PPPL). The primary coil systems for the NCSX device consist of the twisted plasma-shaping Modular Coils, the Poloidal Field Coils, and the Toroidal Field (TF) Coils. The TF Coils are D-shaped coils wound from hollow copper conductor, and vacuum impregnated with a glass-epoxy resin system. There are 18 identical, equally spaced TF coils providing 1/R field at the plasma. They operate within a cryostat, and are cooled by LN2, nominally, to 80K. Wedge shaped castings are assembled to the inboard face of these coils, so that inward radial loads are reacted via the nesting of each of the coils against their adjacent partners. This paper outlines the TF Coil design methodology, reviews the analysis results, and summarizes how the design and analysis support the design requirements

Effects of insulation on potted superconducting coils

International Nuclear Information System (INIS)

Zeller, A.F.; DeKamp, J.C.; Magsig, C.T.; Nolen, J.A.; McInturff, A.D.

1989-01-01

Test coils using identical wire but with either Formvar or Polyesterimid insulation were fabricated to determine the effects of insulation on training behavior. It was found that the type of insulation did not affect the training behavior. While considerable attention has been paid to epoxy formulations used for superconducting coils, little study has been devoted to the effects of the wire insulation on training behavior. If the insulation does not bind well with the epoxy, the wires will not be held securely in place, and training will be required to make the coil operate at its design limit. In fact, the coil may never reach its design current, showing considerable degredation. Conversely, if the epoxy-insulation reaction is to soften or weaken the insulation, then shorts and/or training may result. The authors have undertaken a study of the effects of the insulation on potted coils wet wound with Stycast 2850 FT epoxy. The wire was insulated with one of two insulting varnishes: Formvar (a polyvinyl formal resin) or Polyesterimid (a phenolic resin). Formvar is the standard insulation in the United States while Polyesterimid the European standard

Four signature motifs define the first class of structurally related large coiled-coil proteins in plants.

Directory of Open Access Journals (Sweden)

Meier Iris

2002-04-01

Full Text Available Abstract Background Animal and yeast proteins containing long coiled-coil domains are involved in attaching other proteins to the large, solid-state components of the cell. One subgroup of long coiled-coil proteins are the nuclear lamins, which are involved in attaching chromatin to the nuclear envelope and have recently been implicated in inherited human diseases. In contrast to other eukaryotes, long coiled-coil proteins have been barely investigated in plants. Results We have searched the completed Arabidopsis genome and have identified a family of structurally related long coiled-coil proteins. Filament-like plant proteins (FPP were identified by sequence similarity to a tomato cDNA that encodes a coiled-coil protein which interacts with the nuclear envelope-associated protein, MAF1. The FPP family is defined by four novel unique sequence motifs and by two clusters of long coiled-coil domains separated by a non-coiled-coil linker. All family members are expressed in a variety of Arabidopsis tissues. A homolog sharing the structural features was identified in the monocot rice, indicating conservation among angiosperms. Conclusion Except for myosins, this is the first characterization of a family of long coiled-coil proteins in plants. The tomato homolog of the FPP family binds in a yeast two-hybrid assay to a nuclear envelope-associated protein. This might suggest that FPP family members function in nuclear envelope biology. Because the full Arabidopsis genome does not appear to contain genes for lamins, it is of interest to investigate other long coiled-coil proteins, which might functionally replace lamins in the plant kingdom.

On modular stellarator reactor coils

International Nuclear Information System (INIS)

Rau, F.; Harmeyer, E.; Kisslinger, J.; Wobig, H.

1985-01-01

Modular twisted coils are discussed which produce magnetic fields of the Advanced Stellarator WENDELSTEIN VII-AS type. Reducing the number coils/FP offers advantage for maintenance of coils, but increases the magnetic ripple and B m /B o . Computation of force densities within the coils of ASR and ASB yield local maximum values of about 80 and 180 MN/m 3 , respectively. A system of mutual coil support is being developed. Twisted coils in helical arrangement provide a reactor-sized HELIAC system. In order to reduce the magnetic ripple, a large number of 14 coils/FP in special arrangement is used

Quadruple Cone Coil with improved focality than Figure-8 coil in Transcranial Magnetic Stimulation

Science.gov (United States)

Rastogi, Priyam; Lee, Erik G.; Hadimani, Ravi L.; Jiles, David C.

Transcranial Magnetic Stimulation (TMS) is a non-invasive therapy which uses a time varying magnetic field to induce an electric field in the brain and to cause neuron depolarization. Magnetic coils play an important role in the TMS therapy since their coil geometry determines the focality and penetration's depth of the induced electric field in the brain. Quadruple Cone Coil (QCC) is a novel coil with an improved focality when compared to commercial Figure-8 coil. The results of this newly designed QCC coil are compared with the Figure-8 coil at two different positions of the head - vertex and dorsolateral prefrontal cortex, over the 50 anatomically realistic MRI derived head models. Parameters such as volume of stimulation, maximum electric, area of stimulation and location of maximum electric field are determined with the help of computer modelling of both coils. There is a decrease in volume of brain stimulated by 11.6 % and a modest improvement of 8 % in the location of maximum electric field due to QCC in comparison to the Figure-8 coil. The Carver Charitable Trust and The Galloway Foundation.

Quench performance of a 4-m long Nb3Sn shell-type dipole coil

Energy Technology Data Exchange (ETDEWEB)

Chlachidze, G.; Ambrosio, G.; Andreev, N.; Barzi, E.; Bossert, R.; Carcagno, R.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; /Fermilab

2008-08-01

Fermilab has finished the first phase of Nb{sub 3}Sn technology scale up by testing 2-m and 4-m long shell-type dipole coils in a 'magnetic mirror' configuration. The 2-m long coil, made of Powder-in-Tube (PIT) Nb{sub 3}Sn strand, reached its short sample limit at a field level of 10 T. The 4-m long coil, made of advanced Nb{sub 3}Sn strand based on the Restack Rod Process (RRP) of 108/127 design, has been recently fabricated and tested. Coil test results at 4.5 K and 2.2 K are reported and discussed.

An innovative design for using flexible printed coils for magnetostrictive-based longitudinal guided wave sensors in steel strand inspection

International Nuclear Information System (INIS)

Tse, P W; Liu, X C; Wang, X J; Liu, Z H; Wu, B; He, C F

2011-01-01

Magnetostrictive sensors (MsSs) that can excite and receive guided waves are commonly used in detecting defects that may occur in cables and strands for supporting heavy structures. A conventional MsS has a hard sensing coil that is wound onto a bobbin with electric wires to generate the necessary dynamic magnetic field to excite the desired guided waves. This tailor-made hard coil is usually bulky and is not flexible enough to fit steel strands of various sizes. The conventional MsS also cannot be mounted to any steel strand that does not have a free end to allow the bobbin to pass through the structure of the tested strand. Such inflexibilities limit the use of conventional MsSs in practical situations. To solve these limitations, an innovative type of coil, called a flexible printed coil (FPC), which is made out of flexible printed film, has been designed to replace the inflexible hard coil. The flexible structure of the FPC ensures that the new MsS can be easily installed on and removed from steel strands with different diameters and without free ends. Moreover, the FPC-based MsS can be wrapped into multiple layers due to its thin and flexible design. Although multi-layer FPC creates a minor asymmetry in the dynamic magnetic field, the results of finite element analysis and experiments confirm that the longitudinal guided waves excited by a FPC-based MsS are comparable to those excited by a conventional hard coil MsS. No significant reduction in defect inspection performance was found; in fact, further advantages were identified when using the FPC-based MsS. When acting as the transmitter, the innovative FPC-based MsS can cover a longer inspection length of strand. When acting as the receiver, the FPC-based MsS is more sensitive to smaller defects that are impossible to detect using a hard coil MsS. Hence, the multi-layer FPC-based MsS has great potential for replacing the conventional hard coil MsS because of its convenient installation, and ease of fitting to

Design of the pancake-winding central solenoid coil

International Nuclear Information System (INIS)

Yoshida, Kiyoshi; Nishi, Masataka; Tsuji, Hirosi

1995-01-01

There was a debate over whether a pancake-winding or layer-winding technique is more appropriate for the Central Solenoid (CS) coil for ITER superconducting magnet. The layer-winding CS has the advantage of homogeneous winding supporting the TF centering force without weak joints, but has many difficulties during manufacturing and quality control. On other hand, the pancake-winding has the advantage of better quality control during manufacturing and module testing but has difficulties with joints and feeders, and pipes located in the load path of the bucking force from the toroidal field coils. The compact joints, reinforcement by preformed amour, sharp bending, and double seals are applied to the design of pancake-winding CS coil and demonstrated by hardware developments. The pancake-winding CS coil by using modified existing technology is compatible with the bucking concept of the ITER magnet system. (author)

Irradiation and testing of compact ignition tokamak toroidal field coil insulation materials

International Nuclear Information System (INIS)

Kanemoto, G.K.; Sherick, M.J.; Sparks, D.C.

1990-05-01

This report documents the results of an irradiation and testing program performed on behalf of Martin Marietta Energy Systems, Inc. in support of the Compact Ignition Tokamak Research and Development program. The purpose of the irradiation and testing program was to determine the effects of neutron and gamma irradiation on the mechanical and electrical properties of candidate toroidal field coil insulation materials. Insulation samples were irradiated in the Advanced Test Reactor (ATR) in a large I-hole. The insulation samples were irradiated within a lead shield to reduce exposure to gamma radiation to better approximate the desired ration of neutron to gamma exposure. Two different exposure levels were specified for the insulation samples. To accomplish this, the samples were encapsulated in two separate aluminum capsules; the capsules positioned at the ATR core mid-plane and at the top of the fueled region to take advantage of the axial cosine distribution of the neutron and gamma flux; and by varying the length of irradiation time of the two capsules. Disassembly of the irradiated capsules and testing of the insulation samples were performed at the Test Reactor Area (TRA) Hot Cell Facilities. Testing of the samples included shear compression static, shear compression fatigue, flexure static, and electrical resistance measurements

Immunogenicity of coiled-coil based drug-free macromolecular therapeutics

Czech Academy of Sciences Publication Activity Database

Kverka, Miloslav; Hartley, J.M.; Chu, T.W.; Yang, J.; Heidchen, R.; Kopeček, J.

2014-01-01

Roč. 35, č. 2 (2014), s. 5886-5896 ISSN 1616-0177 R&D Projects: GA MŠk(CZ) EE2.3.30.0003 Grant - others:NIH(US) GM095606 Institutional support: RVO:61388971 Keywords : coiled-coil * enantiomers * HPMA copolymer Subject RIV: EC - Immunology

CCBuilder: an interactive web-based tool for building, designing and assessing coiled-coil protein assemblies.

Science.gov (United States)

Wood, Christopher W; Bruning, Marc; Ibarra, Amaurys Á; Bartlett, Gail J; Thomson, Andrew R; Sessions, Richard B; Brady, R Leo; Woolfson, Derek N

2014-11-01

The ability to accurately model protein structures at the atomistic level underpins efforts to understand protein folding, to engineer natural proteins predictably and to design proteins de novo. Homology-based methods are well established and produce impressive results. However, these are limited to structures presented by and resolved for natural proteins. Addressing this problem more widely and deriving truly ab initio models requires mathematical descriptions for protein folds; the means to decorate these with natural, engineered or de novo sequences; and methods to score the resulting models. We present CCBuilder, a web-based application that tackles the problem for a defined but large class of protein structure, the α-helical coiled coils. CCBuilder generates coiled-coil backbones, builds side chains onto these frameworks and provides a range of metrics to measure the quality of the models. Its straightforward graphical user interface provides broad functionality that allows users to build and assess models, in which helix geometry, coiled-coil architecture and topology and protein sequence can be varied rapidly. We demonstrate the utility of CCBuilder by assembling models for 653 coiled-coil structures from the PDB, which cover >96% of the known coiled-coil types, and by generating models for rarer and de novo coiled-coil structures. CCBuilder is freely available, without registration, at http://coiledcoils.chm.bris.ac.uk/app/cc_builder/. © The Author 2014. Published by Oxford University Press.

Coil development for the quasi-poloidal stellarator project

International Nuclear Information System (INIS)

Nelson, B.E.; Berry, L.A.; Cole, M.J.; Fogarty, P.J.; Freudenberg, K.; Hirshman, S.P.; Lyon, J.F.; Spong, D.A.; Strickler, D.J.; Williamson, D.; Benson, R.D.; Lumsdaine, A.; Madhukar, M.; Parang, M.; Shannon, T.; Dahlgren, F.; Heitzenroeder, P.; Neilson, G.H.; Goranson, P.; Hargrove, T.; Jones, G.; Lovett, G.

2005-01-01

The Quasi-Poloidal Stellarator (QPS), currently in the R and D and prototyping stage, is a low-aspect-ratio (R/a ≥ 2.3), compact stellarator experiment with a non-axisymmetric, near- poloidally-symmetric magnetic field. The QPS design parameters are = 0.95 m, = 0.3-0.4 m, B = 1 T, and a 1.5-s pulse length with 3-5 MW of ECH and ICRF heating power. The most challenging component to design and fabricate is the set of 20 nonplanar modular coils located inside the QPS vacuum tank. There are five distinct coil winding shapes, but only three types of winding forms are needed because each supports two distinct windings and both windings on the most complex coil form are the same shape. The stainless steel winding forms are machined to the required high tolerance and stranded copper cable conductor is wound on the winding forms to the highly precise shape required (to an accuracy of less than 1 mm). The windings are enclosed in a welded, stainless steel cover with stiffeners for compatibility with the QPS vacuum requirements, and the cans are then vacuum pressure impregnated with cynate ester resin to form the finished coil winding pack. Computer modeling and experimental measurements of the welding process indicate that distortion and thermal stress should be acceptable. A prototype coil using the most complex of the three winding forms is being fabricated. The coil winding form has been cast and is being machined to the required tolerance prior to winding with conductor. The machined modular coil forms will be shipped to the winding facility mounted on carts, which provide a work platform for preparing, winding, welding, and potting of the coils. The carts allow rotating the coils for optimum positioning during winding and fabrication. An overhead fixture allows supporting the spools of conductor and feeding the conductor in the correct orientation, groupings, and tensioning. An R and D program is underway that includes extensive conductor characterization and testing

Final Test of the W7-X Control Coils Power Supply and its Integration into the Overall Control Environment

International Nuclear Information System (INIS)

Fuellenbach, F.; Rummel, T.; Pingel, S.; Laqua, H.; Mueller, I.; Jauregi, E.

2006-01-01

In order to be able to vary the magnetic configuration of WENDELSTEIN 7-X (W7-X) at the plasma edge and allow sweeping of the power across the divertor target plates 10 '' control coils '' are installed inside the plasma vessel behind the baffle plates of the divertor. The coils are made of a hollow copper profile with eight turns each. The dimensions of the coils are 2,05 m x 0,35 m x 0,35 m with a three dimensional shape to fit into the narrow space between the baffles and the wall of the plasma vessel. Each of the ten coils is supplied by independent power supplies each providing bi-directionally a direct current of 2500 A with high accuracy and low ripple. To allow sweeping the power deposition from the plasma across the target plates the power supplies provide an alternating current of up to 625 A with frequencies up to 20 Hz which is synchronised between the ten supplies in order to maintain the symmetry of the magnetic field. The total output current of a power supply is a superposition of a direct current and an alternating current, where both parts have to be independently adjustable. JEMA, Spain provided the complete set of power supplies which are based on 10 independent four-quadrant power supplies with a link rectifier and includes a cooling water unit, a dedicated distribution and a central control and visualization system. All ten power supply units and auxiliary systems have meanwhile been installed and finally tested at the W7-X site in Greifswald. The paper focuses on the results of the final tests and measures to integrate the power supply system to the overall control system including the central PLC and PC's for experiment control, data acquisition- and security systems. (author)

Multi-pass spectroscopic ellipsometry

International Nuclear Information System (INIS)

Stehle, Jean-Louis; Samartzis, Peter C.; Stamataki, Katerina; Piel, Jean-Philippe; Katsoprinakis, George E.; Papadakis, Vassilis; Schimowski, Xavier; Rakitzis, T. Peter; Loppinet, Benoit

2014-01-01

Spectroscopic ellipsometry is an established technique, particularly useful for thickness measurements of thin films. It measures polarization rotation after a single reflection of a beam of light on the measured substrate at a given incidence angle. In this paper, we report the development of multi-pass spectroscopic ellipsometry where the light beam reflects multiple times on the sample. We have investigated both theoretically and experimentally the effect of sample reflectivity, number of reflections (passes), angles of incidence and detector dynamic range on ellipsometric observables tanΨ and cosΔ. The multiple pass approach provides increased sensitivity to small changes in Ψ and Δ, opening the way for single measurement determination of optical thickness T, refractive index n and absorption coefficient k of thin films, a significant improvement over the existing techniques. Based on our results, we discuss the strengths, the weaknesses and possible applications of this technique. - Highlights: • We present multi-pass spectroscopic ellipsometry (MPSE), a multi-pass approach to ellipsometry. • Different detectors, samples, angles of incidence and number of passes were tested. • N passes improve polarization ratio sensitivity to the power of N. • N reflections improve phase shift sensitivity by a factor of N. • MPSE can significantly improve thickness measurements in thin films

Fault Analysis of ITER Coil Power Supply System

International Nuclear Information System (INIS)

Song, In Ho; Jun, Tao; Benfatto, Ivone

2009-01-01

The ITER magnet coils are all designed using superconductors with high current carrying capability. The Toroidal Field (TF) coils operate in a steadystate mode with a current of 68 kA and discharge the stored energy in case of quench with using 9 interleaved Fast Discharge Units (FDUs). The Central Solenoid (CS) coils and Poloidal Field (PF) coils operate in a pulse mode with currents of up to 45 kA and require fast variation of currents inducing more than 10 kV during normal operation on the coil terminals using Switching Network (SN) systems (CSs, PF1 and 6) and Booster and VS converters (PF2 to 5), which are series connected to Main converters. SN and FDU systems comprise high current DC circuit breakers and resistors for generating high voltage (SN) and to dissipate magnetic energy (FDUs). High transient voltages can arise due to the switching operation of SN and FD and the characteristics of resistors and stray components of DC distribution systems. Also, faults in power supply control such as shorts or grounding faults can produce higher voltages between terminals and between terminal and ground. Therefore, the design of the coil insulation, coil terminal regions, feeders, feed throughs, pipe breaks and instrumentation must take account of these high voltages during normal and abnormal conditions. Voltage insulation level can be defined and it is necessary to test the coils at higher voltages, to be sure of reliable performance during the lifetime of operation. This paper describes the fault analysis of the TF, CS and PF coil power supply systems, taking account of the stray parameter of the power supply and switching systems and inductively coupled superconducting coil models. Resistor grounding systems are included in the simulation model and all fault conditions such as converter hardware and software faults, switching system hardware and software faults, DC short circuits and single grounding faults are simulated. The occurrence of two successive faults

Trim coil power supplies

International Nuclear Information System (INIS)

Haisler, R.; Peeler, H.; Zajicek, W.

1985-01-01

The 18 trim coil power supplies have been constructed and are now in place in the K500 pit and pit mezzanine. Final wiring of the primary power and control power is proceeding along with installation of cooling water supplies. The supplies are expected to be ready for final testing into resistive loads at the beginning of June, 1985

Protection for low current superconducting coils wound with insulated strand cable

International Nuclear Information System (INIS)

Satti, J.

1980-09-01

The insulated strand cable concept for winding of low current superconducting coil leads to an ideal quench protection by induction coupling. A superconducting secondary loop was made within a cable of a 6.2 Henry dipole coil. When quenching occurred, current was induced in the secondary strand above the critical value. The normal strand quenched the whole cable due to good thermal contact. The secondary loop works as a heater turned on as the wire becomes normal throughout the coil. With a well spread quench, the energy dissipation density is decreased thus preventing local burnout. The mechanism is possible because of close coupling that is present in the insulated cable as in bifilar winding. For the coil tested a 12 strand cable was used, thus a favorable 11 to 1 turn ratio was obtained for the primary to secondary. The superconductor in the secondary had a lower resistance until the critical current was achieved. A theoretical explanation is described for a simplified circuit. Test on the dipole coil with four individual shells showed that the one shell protected with the induced coupling heater always had a more rapid reduction of current. The induced coupling heater tested and explained in this paper works automatically and does not rely on mechanical or electrical devices

Manufacturing of Nb3Sn Sample Conductor for CFETR Central Solenoid Model Coil

NARCIS (Netherlands)

Qin, Jing Gang; Wu, Yu; Xiang, Bing Lun; Dai, Chao; Mao, Zhe Hua; Jin, Huan; Liao, Guo Jun; Liu, Fang; Xue, Tianjun; Wei, Zhou Rong; Devred, Arnaud; Nijhuis, Arend; Zhou, Chao

2017-01-01

China fusion engineering test reactor (CFETR) is a new tokamak device, whose magnet system includes the toroidal field, central solenoid (CS), and poloidal field coils. In order to develop the manufacturing process for the full-size CS coil, the CS model coil (CSMC) project was launched first. The

Coil-On-Plug Ignition for LOX/Methane Liquid Rocket Engines in Thermal Vacuum Environments

Science.gov (United States)

Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

2017-01-01

A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX) / liquid methane rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/methane propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. In order to successfully demonstrate ignition reliability in the vacuum conditions and eliminate corona discharge issues, a coil-on-plug ignition system has been developed. The ICPTA uses spark-plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark-plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp.-2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, Plum Brook testing demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/methane propulsion systems in future spacecraft.

Coil-On-Plug Ignition for Oxygen/Methane Liquid Rocket Engines in Thermal-Vacuum Environments

Science.gov (United States)

Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

2017-01-01

A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX)/liquid methane (LCH4) rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/LCH4 propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. A coil-on-plug ignition system has been developed to successfully demonstrate ignition reliability at these conditions while preventing corona discharge issues. The ICPTA uses spark plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp -2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, hot-fire testing at Plum Brook demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/LCH4 propulsion systems in future spacecraft.

HEDO-2, Magnetic Field Calculation and Plot of Air Core Coils

International Nuclear Information System (INIS)

Preis, H.; Martin, P.

1979-01-01

1 - Nature of physical problem solved: HEDO-2 allows calculation of the magnetic field, magnetic volume forces, and the self and mutual inductance coefficients of arbitrary air-core coil systems. In addition, the program is suitable for the calculation and graphic representation of field and contour lines (lines B = const). 2 - Method of solution: Approximation of the spatially distributed currents by line currents, in which the number of closed line currents per coil can be freely chosen in accordance with the calculating accuracy required. All types of calculations possible with HEDO-2 are based on the field representation of line currents. 3 - Restrictions on the complexity of the problem: (a) The coils must have rectangular winding cross sections. (b) The contour of each coil must be symmetric to at least one coordinate axis. (c) The function describing the contour and the derivative of the function must be continuous. (d) Maximum number of coils n=200; (e) Maximum number of test points p=2000; (f) Test points ought not to be located on a line conductor

Coil measurement data acquisition and curing press control system for SSC dipole magnet coils

International Nuclear Information System (INIS)

Dickey, C.E.

1989-03-01

A coil matching program, similar in theory to the methods used to match Tevatron coils, is being developed at Fermilab. Modulus of elasticity and absolute coil size will be determined at 18-inch intervals along the coils while in the coil curing press immediately following the curing process. A data acquisition system is under construction to automatically acquire and manage the large quantities of data that result. Data files will be transferred to Fermilab's VAX Cluster for long-term storage and actual coil matching. The data acquisition system will also provide the control algorithm for the curing press hydraulic system. A description of the SSC Curing Press Data Acquisition and Controls System will be reported. 20 figs

Development of a 5.1 T conduction-cooled YBCO coil composed of a stack of 12 single pancakes

Energy Technology Data Exchange (ETDEWEB)

Miyazaki, Hiroshi, E-mail: hiroshi17.miyazaki@toshiba.co.jp [Toshiba Corporation, Power Systems Company, 2-4 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan); Iwai, Sadanori; Tosaka, Taizo; Tasaki, Kenji; Hanai, Satoshi; Urata, Masami; Ioka, Shigeru; Ishii, Yusuke [Toshiba Corporation, Power Systems Company, 2-4 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan)

2013-01-15

Highlights: ► We confirmed that performance of YBCO coil was improved by using APC wire. ► We made a conduction-cooled YBCO coil composed of a stack of 12 single pancakes. ► The coil had a central magnetic field as high as 5.1 T at 10 K. ► We also tested the coil operation in a 4 T background magnetic field. -- Abstract: We fabricated and tested a 5 T-class conduction-cooled high-temperature superconducting (HTS) coil composed of a stack of 12 single pancake coils wound with YBCO-coated conductors. The length of each single pancake coil was 25 m, and the inner diameter of the coil was 50 mm. The voltage–current characteristics were measured in liquid nitrogen and under conduction-cooled conditions at 10–60 K. At 10 K, the central magnetic field of the 12 stacked pancake coils was as high as 5.1 T at 305 A. We also tested the coil operation in a 4 T background magnetic field.

Open coil traction system.

Science.gov (United States)

Vibhute, Pavankumar Janardan

2012-01-01

Sliding mechanics have become a popular method for space closure, with the development of preadjusted edgewise appliances. Furthermore, various space closing auxiliaries have been developed and extensively evaluated for their clinical efficiency. Their effectiveness is enhanced with optimum force magnitude and low load deflection rate/force decay. With the advent of nickel-titanium (Ni-Ti) springs in orthodontics, load deflection rates have been markedly reduced. To use Ni-Ti springs, clinicians have to depend upon prefabricated closed coil springs. The open coil traction system, or open coil retraction spring, is developed utilizing Ni-Ti open coil springs for orthodontic space closure. This article describes the fabrication and clinical application of the open coil traction system, which has a number of advantages. It sustains a low load deflection rate with optimum force magnitude, and its design is adjustable for a desired length and force level. It is fail-safe for both activation and deactivation (ie, it cannot be overactivated, and the decompression limit of the open coil is controlled by the operator). The open coil traction system can be offset from the mucosa to help reduce soft tissue impingement.

Plasmodium vivax antigen discovery based on alpha-helical coiled coil protein motif.

Directory of Open Access Journals (Sweden)

Nora Céspedes

Full Text Available Protein α-helical coiled coil structures that elicit antibody responses, which block critical functions of medically important microorganisms, represent a means for vaccine development. By using bioinformatics algorithms, a total of 50 antigens with α-helical coiled coil motifs orthologous to Plasmodium falciparum were identified in the P. vivax genome. The peptides identified in silico were chemically synthesized; circular dichroism studies indicated partial or high α-helical content. Antigenicity was evaluated using human sera samples from malaria-endemic areas of Colombia and Papua New Guinea. Eight of these fragments were selected and used to assess immunogenicity in BALB/c mice. ELISA assays indicated strong reactivity of serum samples from individuals residing in malaria-endemic regions and sera of immunized mice, with the α-helical coiled coil structures. In addition, ex vivo production of IFN-γ by murine mononuclear cells confirmed the immunogenicity of these structures and the presence of T-cell epitopes in the peptide sequences. Moreover, sera of mice immunized with four of the eight antigens recognized native proteins on blood-stage P. vivax parasites, and antigenic cross-reactivity with three of the peptides was observed when reacted with both the P. falciparum orthologous fragments and whole parasites. Results here point to the α-helical coiled coil peptides as possible P. vivax malaria vaccine candidates as were observed for P. falciparum. Fragments selected here warrant further study in humans and non-human primate models to assess their protective efficacy as single components or assembled as hybrid linear epitopes.

Nondestructive testing bench without rotation

International Nuclear Information System (INIS)

Perdijon, J.

1976-01-01

On-line testing by ultrasonics in combination with eddy currents represents a large saving in time and equipment since the tube to be checked only needs to pass once quickly and without rotation. The answer to this problem is to use encircling transducers, which means that the mirror interposed to detect transverse defects must be conical while that used to detect longitudinal defects is helically shaped. A cell combining these two mirrors with an eddy current coil to test thin small-diameter tubes is described. The first trial year shows that defects are detected independently of their position, with a sensitivity at least equal to that of conventional systems [fr

Split coil made of (RE)BCO pancake coils for IC(B) anisotropy measurements of superconductors

International Nuclear Information System (INIS)

Frolek, L; Pardo, E; Gömöry, F; Šouc, J; Pitel, J

2014-01-01

Measurement of the I c (B) anisotropy is standard characterization of superconducting tapes, wires or cables. This contribution presents a split coil consisting on two superconducting pancake coils in order to generate the magnetic field necessary for this kind of measurement. Both coils were made using (RE)BCO – based second generation (2G) coated conductor tape with cross section 0.1 mm × 12 mm. The individual turns of the tape were insulated by a fiberglass tape without impregnation. These coils have identical inner and outer diameter and number of turns. Their inner and outer diameters are 50 mm and 80 mm, respectively, and they have 62 turns. The length of conductor in each coil is approximately 13 m. The distance between both pancake coils is 22 mm. Individual coils and the complete split coil were characterized in liquid nitrogen bath. Their parameters, like the critical currents, E(I) characteristics and magnetic field of complete split coil, were measured and interpreted. The split coil can be used up to magnetic fields of 210 mT. The length between the potential taps on the sample can be up to 20 mm, while the magnetic field decrease is lower than 1% on this length.

Unraveling double stranded alpha-helical coiled coils: an x-ray diffraction study on hard alpha-keratin fibers.

Science.gov (United States)

Kreplak, L; Doucet, J; Briki, F

2001-04-15

Transformations of proteins secondary and tertiary structures are generally studied in globular proteins in solution. In fibrous proteins, such as hard alpha-keratin, that contain long and well-defined double stranded alpha-helical coiled coil domains, such study can be directly done on the native fibrous tissue. In order to assess the structural behavior of the coiled coil domains under an axial mechanical stress, wide angle x-ray scattering and small angle x-ray scattering experiments have been carried out on stretched horse hair fibers at relative humidity around 30%. Our observations of the three major axial spacings as a function of the applied macroscopic strain have shown two rates. Up to 4% macroscopic strain the coiled coils were slightly distorted but retained their overall conformation. Above 4% the proportion of coiled coil domains progressively decreased. The main and new result of our study is the observation of the transition from alpha-helical coiled coils to disordered chains instead of the alpha-helical coiled coil to beta-sheet transition that occurs in wet fibers.

The coiled coil motif in polymer drug delivery systems

Czech Academy of Sciences Publication Activity Database

Pechar, Michal; Pola, Robert

2013-01-01

Roč. 31, č. 1 (2013), s. 90-96 ISSN 0734-9750 R&D Projects: GA ČR GA203/08/0543; GA MŠk 1M0505 Institutional research plan: CEZ:AV0Z40500505 Keywords : coiled coil * hydrophilic polymer * recombinant protein Subject RIV: CD - Macromolecular Chemistry Impact factor: 8.905, year: 2013

Impact of endobronchial coiling on segmental bronchial lumen in treated and untreated lung lobes: Correlation with changes in lung volume, clinical and pulmonary function tests.

Science.gov (United States)

Kloth, C; Thaiss, W M; Hetzel, J; Ditt, H; Grosse, U; Nikolaou, K; Horger, M

2016-07-01

To assess the impact of endobronchial coiling on the segment bronchus cross-sectional area and volumes in patients with lung emphysema using quantitative chest-CT measurements. Thirty patients (female = 15; median age = 65.36 years) received chest-CT before and after endobronchial coiling for lung volume reduction (LVR) between January 2010 and December 2014. Thin-slice (0.6 mm) non-enhanced image data sets were acquired both at end-inspiration and end-expiration using helical technique and 120 kV/100-150 mAs. Clinical response was defined as an increase in the walking distance (Six-minute walk test; 6MWT) after LVR-therapy. Additionally, pulmonary function test (PFT) measurements were used for clinical correlation. In the treated segmental bronchia, the cross-sectional lumen area showed significant reduction (p  0.05). In the ipsilateral lobes, the lumina showed no significant changes. In the contralateral lung, we found tendency towards increased cross-sectional area in inspiration (p = 0.06). Volumes of the treated segments correlated with the treated segmental bronchial lumina in expiration (r = 0.80, p volume of the treated lobe in responders only. Endobronchial coiling causes significant decrease in the cross-sectional area of treated segment bronchi in inspiration and a slight increase in expiration accompanied by a volume reduction. • Endobronchial coiling has indirect impact on cross-sectional area of treated segment bronchi • Volume changes of treated lobes correlate with changes in bronchial cross-sectional area • Coil-induced effects reflect their stabilizing and stiffening impact on lung parenchyma • Endobronchial coiling reduces bronchial collapsing compensating the loss of elasticity.

A new type of coil structure called pan-shaped coil of wireless charging system based on magnetic resonance

Science.gov (United States)

Yue, Z. K.; Liu, Z. Z.; Hou, Y. J.; Zeng, H.; Liang, L. H.; Cui, S.

2017-11-01

The problem that misalignment between the transmitting coil and the receiving coil significantly impairs the transmission power and efficiency of the system has been attached more and more attention. In order to improve the uniformity of the magnetic field between the two coils to solve this problem, a new type of coil called pan-shaped coil is proposed. Three-dimension simulation models of the planar-core coil and the pan-shaped coil are established using Ansoft Maxwell software. The coupling coefficient between the transmitting coil and the receiving coil is obtained by simulating the magnetic field with the receiving coil misalignment or not. And the maximum percentage difference strength along the radial direction which is defined as the magnetic field uniformity factor is calculated. According to the simulation results of the two kinds of coil structures, it is found that the new type of coil structure can obviously improve the uniformity of the magnetic field, coupling coefficient and power transmission properties between the transmitting coil and the receiving coil.

Coil protection calculator for TFTR

International Nuclear Information System (INIS)

Marsala, R.J.; Woolley, R.D.

1987-01-01

A new coil protection calculator (CPC) is presented in this paper. It is now being developed for TFTR's magnetic field coils will replace the existing coil fault detector. The existing fault detector sacrifices TFTR operating capability for simplicity. The new CPC will permit operation up to the actual coil limits by accurately and continuously computing coil parameters in real-time. The improvement will allow TFTR to operate with higher plasma currents and will permit the optimization of pulse repetition rates

Performance evaluation of matrix gradient coils.

Science.gov (United States)

Jia, Feng; Schultz, Gerrit; Testud, Frederik; Welz, Anna Masako; Weber, Hans; Littin, Sebastian; Yu, Huijun; Hennig, Jürgen; Zaitsev, Maxim

2016-02-01

In this paper, we present a new performance measure of a matrix coil (also known as multi-coil) from the perspective of efficient, local, non-linear encoding without explicitly considering target encoding fields. An optimization problem based on a joint optimization for the non-linear encoding fields is formulated. Based on the derived objective function, a figure of merit of a matrix coil is defined, which is a generalization of a previously known resistive figure of merit for traditional gradient coils. A cylindrical matrix coil design with a high number of elements is used to illustrate the proposed performance measure. The results are analyzed to reveal novel features of matrix coil designs, which allowed us to optimize coil parameters, such as number of coil elements. A comparison to a scaled, existing multi-coil is also provided to demonstrate the use of the proposed performance parameter. The assessment of a matrix gradient coil profits from using a single performance parameter that takes the local encoding performance of the coil into account in relation to the dissipated power.

Cooling a solar telescope enclosure: plate coil thermal analysis

Science.gov (United States)

Gorman, Michael; Galapon, Chriselle; Montijo, Guillermo; Phelps, LeEllen; Murga, Gaizka

2016-08-01

The climate of Haleakalā requires the observatories to actively adapt to changing conditions in order to produce the best possible images. Observatories need to be maintained at a temperature closely matching ambient or the images become blurred and unusable. The Daniel K. Inouye Solar Telescope is a unique telescope as it will be active during the day as opposed to the other night-time stellar observatories. This means that it will not only need to constantly match the ever-changing temperature during the day, but also during the night so as not to sub-cool and affect the view field of other telescopes while they are in use. To accomplish this task, plate coil heat exchanger panels will be installed on the DKIST enclosure that are designed to keep the temperature at ambient temperature +0°C/-4°C. To verify the feasibility of this and to validate the design models, a test rig has been installed at the summit of Haleakalā. The project's purpose is to confirm that the plate coil panels are capable of maintaining this temperature throughout all seasons and involved collecting data sets of various variables including pressures, temperatures, coolant flows, solar radiations and wind velocities during typical operating hours. Using MATLAB, a script was written to observe the plate coil's thermal performance. The plate coil did not perform as expected, achieving a surface temperature that was generally 2ºC above ambient temperature. This isn't to say that the plate coil does not work, but the small chiller used for the experiment was undersized resulting in coolant pumped through the plate coil that was not supplied at a low enough temperature. Calculated heat depositions were about 23% lower than that used as the basis of the design for the hillers to be used on the full system, a reasonable agreement given the fact that many simplifying assumptions were used in the models. These were not carried over into the testing. The test rig performance showing a 23% margin

Quench detection/protection of an HTS coil by AE signals

International Nuclear Information System (INIS)

Yoneda, M.; Nanato, N.; Aoki, D.; Kato, T.; Murase, S.

2011-01-01

A quench detection/protection system based on measuring AE signals was developed. The system was tested for a Bi2223 coil. Temperature rise after a quench occurrence was restrained at very low value. The normal zone propagation velocities in high T c superconductors are slow at high operation temperature and therefore local and excessive temperature rise generates at quench occurrence, and then the superconductors are degraded or burned. Therefore it is essential to detect the temperature rise in high T c superconducting (HTS) coils as soon as possible and protect them. The authors have presented a quench detection method for HTS coils by time-frequency visualization of AE signals and have shown its usefulness for a HTS coil with height and outer diameter of 40-50 mm. In this paper, the authors present a quench detection/protection system based on superior method in quench detection time to the previous method and show its usefulness for a larger HTS coil (height and outer diameter: 160-190 mm) than the previous coil.

Suppression of m = 0 in a RFP by toroidal field coils

International Nuclear Information System (INIS)

Alexander, D.; Robertson, S.

1993-01-01

The Reversatron RFP is normally operated with the toroidal field coils connected in series. The time-integrated voltage applied to the circuit determines the sum of the fluxes linking each turn but not the flux within each turn. Each winding may have a different flux determined by the external drive and by currents within the plasma. A parallel connection of the field coils results in the flux within each coil being determined by the volt-seconds applied to the windings; thus the toroidal flux is the same within each coil. This configuration suppresses any toroidal variation in the toroidal flux and effectively reduces the level of the m = 0 component of the radial field. The m = 0 fluctuations are expected to arise due to nonlinear coupling of the m = 1 modes. A parallel connection of field coils is impractical due to the low impedance required for driving the coils. The authors have tested the effect of parallel connected coils by adding an auxiliary set of 36 coils. These are connected in parallel but are not connected to any supply. The toroidal flux is generated by the series-connected coils which generate voltage but not current in the parallel-connected coils. With the auxiliary coils, the discharge duration is increased from 500 to 550 μsec, the plasma current is increased from 50 kA to 60 kA, F is more negative, Θ is larger, and there is less shot-to-shot variation in the discharges. The m = 0 fluctuations measured by 43 surface coils are, however, only slightly reduced

Supporting device for Toroidal coils

International Nuclear Information System (INIS)

Araki, Takao.

1985-01-01

Purpose: To reduce the response of a toroidal coil supporting device upon earthquakes and improve the earthquake proofness in a tokamak type thermonuclear device. Constitution: Structural materials having large longitudinal modulus and enduring great stresses, for example, stainless steels are used as the toroidal coil supporting legs and heat insulating structural materials are embedded in a nuclear reactor base mats below the supporting legs. Furthermore, heat insulating concretes are spiked around the heat insulating structural materials to prevent the intrusion of heat to the toroidal coils. The toroidal coils are kept at cryogenic state and superconductive state for the conductors. In this way, the period of proper vibrations of the toroidal coils and the toroidal coil supporting structures can be shortened thereby decreasing the seismic response. Furthermore, since the strength of the supporting legs is increased, the earthquake proofness of the coils can be improved. (Kamimura, M.)

Fifty years of coiled-coils and alpha-helical bundles: a close relationship between sequence and structure.

Science.gov (United States)

Parry, David A D; Fraser, R D Bruce; Squire, John M

2008-09-01

alpha-Helical coiled coils are remarkable for the diversity of related conformations that they adopt in both fibrous and globular proteins, and for the range of functions that they exhibit. The coiled coils are based on a heptad (7-residue), hendecad (11-residue) or a related quasi-repeat of apolar residues in the sequences of the alpha-helical regions involved. Most of these, however, display one or more sequence discontinuities known as stutters or stammers. The resulting coiled coils vary in length, in the number of chains participating, in the relative polarity of the contributing alpha-helical regions (parallel or antiparallel), and in the pitch length and handedness of the supercoil (left- or right-handed). Functionally, the concept that a coiled coil can act only as a static rod is no longer valid, and the range of roles that these structures have now been shown to exhibit has expanded rapidly in recent years. An important development has been the recognition that the delightful simplicity that exists between sequence and structure, and between structure and function, allows coiled coils with specialized features to be designed de novo.

High-field superconducting nested coil magnet

Science.gov (United States)

Laverick, C.; Lobell, G. M.

1970-01-01

Superconducting magnet, employed in conjunction with five types of superconducting cables in a nested solenoid configuration, produces total, central magnetic field strengths approaching 70 kG. The multiple coils permit maximum information on cable characteristics to be gathered from one test.

Thermo hydraulic and quench propagation characteristics of SST-1 TF coil

Energy Technology Data Exchange (ETDEWEB)

Sharma, A.N., E-mail: ansharma@ipr.res.in [Institute for Plasma Research, Gandhinagar (India); Pradhan, S. [Institute for Plasma Research, Gandhinagar (India); Duchateau, J.L. [CEA Cadarache, 13108 St Paul lez Durance Cedex (France); Khristi, Y.; Prasad, U.; Doshi, K.; Varmora, P.; Patel, D.; Tanna, V.L. [Institute for Plasma Research, Gandhinagar (India)

2014-02-15

Highlights: • Details of SST-1 TF coils, CICC. • Details of SST-1 TF coil cold test. • Quench analysis of TF magnet. • Flow changes following quench. • Predictive analysis of assembled magnet system. - Abstract: SST-1 toroidal field (TF) magnet system is comprising of sixteen superconducting modified ‘D’ shaped TF coils. During single coil test campaigns spanning from June 10, 2010 till January 24, 2011; the electromagnetic, thermal hydraulic and mechanical performances of each TF magnet have been qualified at its respective nominal operating current of 10,000 A in either two-phase or supercritical helium cooling conditions. During the current charging experiments, few quenches have initiated either as a consequence of irrecoverable normal zones or being induced in some of the TF magnets. Quench evolution in the TF coils have been analyzed in detail in order to understand the thermal hydraulic and quench propagation characteristics of the SST-1 TF magnets. The same were also simulated using 1D code Gandalf. This paper elaborates the details of the analyses and the quench simulation results. A predictive quench propagation analysis of 16 assembled TF magnets system has also been reported in this paper.

Controller design and test results for a four axis HTS coil based Maglev system

International Nuclear Information System (INIS)

Zhou Tong; Xing Huawei

2007-01-01

Controller design and experimental results are reported in this paper for a four axis high temperature superconductivity (HTS) coil based electromagnetic levitation (Maglev) system. The HTS coils are made of Bi2223/Ag multifilamentary tapes. It has been experimentally proved that the designed controller works satisfactorily, although the physical parameters of a HTS coil based electromagnet (HTSEM) vary significantly with the frequency of the input voltage. A performance comparison has also been made between the classical lead-lag compensator and the modern H ∼ loop-shaping controller. It becomes clear that robust control theories are capable of providing a controller with better performances, which is in a good agreement with numerical simulations. Moreover, it implies that the particular parameter variation characteristics can be simply dealt with by the available robust control theories that are naturally existent in a HTSEM

Controller design and test results for a four axis HTS coil based Maglev system

Energy Technology Data Exchange (ETDEWEB)

Zhou Tong [Department of Automation, Tsinghua University, Beijing 100084 (China)]. E-mail: tzhou@mail.tsinghua.edu.cn; Xing Huawei [Department of Automation, Tsinghua University, Beijing 100084 (China)

2007-04-15

Controller design and experimental results are reported in this paper for a four axis high temperature superconductivity (HTS) coil based electromagnetic levitation (Maglev) system. The HTS coils are made of Bi2223/Ag multifilamentary tapes. It has been experimentally proved that the designed controller works satisfactorily, although the physical parameters of a HTS coil based electromagnet (HTSEM) vary significantly with the frequency of the input voltage. A performance comparison has also been made between the classical lead-lag compensator and the modern H{sub {approx}} loop-shaping controller. It becomes clear that robust control theories are capable of providing a controller with better performances, which is in a good agreement with numerical simulations. Moreover, it implies that the particular parameter variation characteristics can be simply dealt with by the available robust control theories that are naturally existent in a HTSEM.

Magnetic field measurements of JT-60SA CS model coil

Energy Technology Data Exchange (ETDEWEB)

Obana, Tetsuhiro, E-mail: obana.tetsuhiro@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Takahata, Kazuya; Hamaguchi, Shinji; Chikaraishi, Hirotaka; Mito, Toshiyuki; Imagawa, Shinsaku [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kizu, Kaname; Murakami, Haruyuki; Natsume, Kyohei; Yoshida, Kiyoshi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

2015-01-15

Highlights: • Magnetic fields of the JT-60SA CS model coil were measured. • While the coil current was held constant at 20 kA, magnetic fields varied slightly with several different long time constants. • We investigated coils consisting of CIC conductors and having long time constants. - Abstract: In a cold test of the JT-60SA CS model coil, which has a quad-pancake configuration consisting of a Nb{sub 3}Sn cable-in-conduit (CIC) conductor, magnetic fields were measured using Hall sensors. For a holding coil current of 20 kA, measured magnetic fields varied slightly with long time constants in the range 17–571 s, which was much longer than the time constant derived from a measurement using a short straight sample. To validate the measurements, the magnetic fields of the model coil were calculated using a computational model representing the positions of Nb{sub 3}Sn strands inside the CIC conductor. The calculated results were in good agreement with the measurements. Consequently, the validity of the magnetic field measurements was confirmed. Next, we investigated other coils consisting of CIC conductors and having long time constants. The only commonality among the coils was the use of CIC conductors. At present, there is no obvious way to prevent generation of such magnetic-field variations with long time constants.

Transition of W7-X non-planar coils from manufacturing to assembly

Energy Technology Data Exchange (ETDEWEB)

Ehrke, G. [Max-Planck-Institut fuer Plasmaphysik (IPP), EURATOM Association, Wendelsteinstrasse 1, D-17491 Greifswald (Germany)], E-mail: gunnar.ehrke@ipp.mpg.de

2009-06-15

The main magnetic field of Wendelstein 7-X fusion experiment (W7-X) at Max-Planck-Institut fuer Plasmaphysik Greifswald, Germany will be provided by 50 non-planar coils and supported by 20 planar coils. The non-planar coils were delivered by a consortium (CON) consisting of Babcock Noell GmbH Germany (BNG) and ASG Superconductors S.p.A. Italy (ASG). The coil production ended with the delivery of the last non-planar coil in March 2008 at the manufacturing branch of BNG in Zeitz, Germany. The construction of the coils was characterised by design changes, many rework actions and resulting time delays. Due to these numerous adjustments and changes a continuous improvement process was needed. This paper will give an overview about the transition of the non-planar coils from the acceptance tests at the manufacturer site to the beginning of the assembly at IPP. Furthermore this report will highlight technical interfaces in the period of transition.

Design of a quadrature surface coil for hyperpolarized 13C MRS cardiac metabolism studies in pigs

DEFF Research Database (Denmark)

Giovannetti, G.; Frijia, F.; Hartwig, V.

2013-01-01

, the performance of the quadrature coil was compared with the single TX/RX circular and TX/RX butterfly coil, in order to verify the advantage of the proposed configuration over the single coils throughout the volume of interest for cardiac imaging in pig. Finally, the quadrature surface coil was tested...

Versatile fill coils: initial experience as framing coils for oblong aneurysms. A technical case report.

Science.gov (United States)

Osanai, Toshiya; Bain, Mark; Hui, Ferdinand K

2014-01-01

Coil embolization of oblong aneurysms is difficult because the majority of commercially available coils are manufactured with a helical or spherical tertiary structure. While adopting framing strategies for oblong aneurysms (aspect ratio ≥ 2: 1), traditional coils may be undersized in the long axis but oversized in the short axis, resulting in increased aneurysmal wall stress, risk of re-rupture, and difficulty creating a basket that respects the aneurysmal neck. We review three cases in which versatile filling coils (VFCs) were used as the initial coils for embolization of oblong aneurysms and report coil distribution characteristics and clinical outcomes. Packing density after VFC implantation was assessed using the software AngioSuite-Neuro edition and AngioCalc. a 58-year-old woman experienced a subarachnoid hemorrhage from a ruptured anterior communicating artery aneurysm (7.5 mm × 3.5 mm). A 3-6 mm × 15 cm VFC was selected as the first coil because the flexibility of its wave-loop structure facilitates framing of an irregularly shaped aneurysm. The loop portions of the structures tend to be pressed to the extremes of the aneurysmal sac by the wave component. The VFC was introduced smoothly into the aneurysmal sac without catheter kickback. We were then able to insert detachable filling coils without any adjunctive technique and achieved complete occlusion. Complete occlusion without severe complications was achieved in all three cases in our study. Average packing density after the first coil was 15.63%. VFC coils may have a specific role in framing oblong aneurysms given their complex loop-wave design, allowing spacing of the coils at the dome and neck while keeping sac stress to a minimum.

Commercial applications for COIL

Science.gov (United States)

Solomon, Wayne C.; Carroll, David L.; King, D. M.; Fockler, L. A.; Stromberg, D. S.; Sexauer, M.; Milmoe, A.; Sentman, Lee H.

2000-01-01

The chemical oxygen-iodine laser (COIL) is a high power, fiber deliverable tool, which can be used for a number of different industrial applications. COIL is of particular interest because of its short fiber deliverable wavelength, high scaleable continuous wave power, and excellent material interaction properties. In past research the University of Illinois at Urbana-Champaign identified and decommissioning and decontamination (DD) of nuclear facilities as a primary focus for COIL technology. DD will be a major challenge in the coming decades. The use of a robotically driven fiber delivered cutting/ablation tool in contaminated areas promises to lower risks to workers for the DD mission. Further, the high cutting speed of COIL will significantly reduce the time required to cut contaminated equipment, reducing costs. The high power of COIL will permit the dismantling of thick stacks of piping and equipment as well as reactor vessels. COIL is very promising for the removal of material from contaminated surfaces, perhaps to depths thicker than an inch. Laser cutting and ablation minimizes dust and fumes, which reduces the required number of high efficiency particulate accumulator filters, thus reducing costly waste disposal. Other potential industrial applications for COIL are shipbuilding, automotive manufacturing, heavy machinery manufacturing, tasks requiring underwater cutting or welding, and there appear to be very promising applications for high powers lasers in the oil industry.

The heterotrimeric laminin coiled-coil domain exerts anti-adhesive effects and induces a pro-invasive phenotype.

Directory of Open Access Journals (Sweden)

Patricia Santos-Valle

Full Text Available Laminins are large heterotrimeric cross-shaped extracellular matrix glycoproteins with terminal globular domains and a coiled-coil region through which the three chains are assembled and covalently linked. Laminins are key components of basement membranes, and they serve as attachment sites for cell adhesion, migration and proliferation. In this work, we produced a recombinant fragment comprising the entire laminin coiled-coil of the α1-, β1-, and γ1-chains that assemble into a stable heterotrimeric coiled-coil structure independently of the rest of the molecule. This domain was biologically active and not only failed to serve as a substrate for cell attachment, spreading and focal adhesion formation but also inhibited cell adhesion to laminin when added to cells in a soluble form at the time of seeding. Furthermore, gene array expression profiling in cells cultured in the presence of the laminin coiled-coil domain revealed up-regulation of genes involved in cell motility and invasion. These findings were confirmed by real-time quantitative PCR and zymography assays. In conclusion, this study shows for the first time that the laminin coiled-coil domain displays anti-adhesive functions and has potential implications for cell migration during matrix remodeling.

Equilibrium field coil concepts for INTOR

International Nuclear Information System (INIS)

Strickler, D.J.; Peng, Y.K.M.; Brown, T.G.

1981-08-01

Methods are presented for reducing ampere-turn requirements in the EF coil system. It is shown that coil currents in an EF coil system external to the toroidal field coils can be substantially reduced by relaxing the triangularity of a D-shaped plasma. Further reductions are realized through a hybrid EF coil system using both internal and external coils. Equilibrium field coils for a poloidally asymmetric, single-null INTOR configuration are presented. It is shown that the shape of field lines in the plasma scrapeoff region and divertor channel improves as triangularity is reduced, but it does so at the possible expense of achievable stable beta values

Program NICOLET to integrate energy loss in superconducting coils. [In FORTRAN for CDC-6600

Energy Technology Data Exchange (ETDEWEB)

Vogel, H.F.

1978-08-01

A voltage pickup coil, inductively coupled to the magnetic field of the superconducting coil under test, is connected so its output may be compared with the terminal voltage of the coil under test. The integrated voltage difference is indicative of the resistive volt-seconds. When multiplied with the main coil current, the volt-seconds yield the loss. In other words, a hysteresis loop is obtained if the integrated voltage difference phi = ..integral delta..Vdt is plotted as a function of the coil current, i. First, time functions of the two signals phi(t) and i(t) are recorded on a dual-trace digital oscilloscope, and these signals are then recorded on magnetic tape. On a CDC-6600, the recorded information is decoded and plotted, and the hysteresis loops are integrated by the set of FORTRAN programs NICOLET described in this report. 4 figures.

Desarrollo de un cerrojo artificial para el skin-pass en una línea de acero galvanizado por inmersión en caliente

Directory of Open Access Journals (Sweden)

González-Marcos, A.

2008-02-01

Full Text Available In this paper, we present the application of data mining techniques to develop an “artificial lock” for the skin-pass in an attempt to solve a problem that can arise during the galvanising manufacturing process: the wrong labelling of the steel grade of a coil. In order to detect these errors and thus to avoid that coils with different properties than expected end up with a client, we propose neural network-based models for on-line predicting the strip elongation in the skin-pass section according to the manufacturing conditions and its chemical composition. Thus, a significant difference between estimated and measured elongation would mean that the coil must be removed from the line for further analyses.

En este trabajo se presenta la aplicación de técnicas de minería de datos en el desarrollo de un “cerrojo artificial” para el skin-pass, que permita solucionar un problema que puede presentarse en la fabricación de bobinas de acero galvanizado: el etiquetado incorrecto del grado de acero de una bobina. Para tratar de detectar estos errores y evitar así que los clientes reciban bobinas con propiedades distintas de las esperadas, se proponen modelos, basados en redes neuronales, que predicen on-line el alargamiento de las bobinas en el skin-pass en función de las variables del proceso de fabricación y de su composición química. De esta forma, si la diferencia entre el alargamiento que estima el modelo y el medido realmente es significativa, se hace necesario sacar la bobina de la línea para someterla a análisis más exhaustivos.

Exploring the conserved water site and hydration of a coiled-coil trimerisation motif: a MD simulation study.

Science.gov (United States)

Dolenc, Jozica; Baron, Riccardo; Missimer, John H; Steinmetz, Michel O; van Gunsteren, Wilfred F

2008-07-21

The solvent structure and dynamics around ccbeta-p, a 17-residue peptide that forms a parallel three-stranded alpha-helical coiled coil in solution, was analysed through 10 ns explicit solvent molecular dynamics (MD) simulations at 278 and 330 K. Comparison with two corresponding simulations of the monomeric form of ccbeta-p was used to investigate the changes of hydration upon coiled-coil formation. Pronounced peaks in the solvent density distribution between residues Arg8 and Glu13 of neighbouring helices show the presence of water bridges between the helices of the ccbeta-p trimer; this is in agreement with the water sites observed in X-ray crystallography experiments. Interestingly, this water site is structurally conserved in many three-stranded coiled coils and, together with the Arg and Glu residues, forms part of a motif that determines three-stranded coiled-coil formation. Our findings show that little direct correlation exists between the solvent density distribution and the temporal ordering of water around the trimeric coiled coil. The MD-calculated effective residence times of up to 40 ps show rapid exchange of surface water molecules with the bulk phase, and indicate that the solvent distribution around biomolecules requires interpretation in terms of continuous density distributions rather than in terms of discrete molecules of water. Together, our study contributes to understanding the principles of three-stranded coiled-coil formation.

Bow-shaped toroidal field coils

International Nuclear Information System (INIS)

Bonanos, P.

1981-05-01

Design features of Bow-Shaped Toroidal Field Coils are described and compared with circular and D shaped coils. The results indicate that bow coils can produce higher field strengths, store more energy and be made demountable. The design offers the potential for the production of ultrahigh toroidal fields. Included are representative coil shapes and their engineering properties, a suggested structural design and an analysis of a specific case

Flow-induced vibration of helical coil compression springs

International Nuclear Information System (INIS)

Stokes, F.E.; King, R.A.

1983-01-01

Helical coil compression springs are used in some nuclear fuel assembly designs to maintain holddown and to accommodate thermal expansion. In the reactor environment, the springs are exposed to flowing water, elevated temperatures and pressures, and irradiation. Flow parallel to the longitudinal axis of the spring may excite the spring coils and cause vibration. The purpose of this investigation was to determine the flow-induced vibration (FIV) response characteristics of the helical coil compression springs. Experimental tests indicate that a helical coil spring responds like a single circular cylinder in cross-flow. Two FIV excitation mechanisms control spring vibration. Namely: 1) Turbulent Buffeting causes small amplitude vibration which increases as a function of velocity squared. 2) Vortex Shedding causes large amplitude vibration when the spring natural frequency and Strouhal frequency coincide. Several methods can be used to reduce or to prevent vortex shedding large amplitude vibrations. One method is compressing the spring to a coil pitch-to-diameter ratio of 2 thereby suppressing the vibration amplitude. Another involves modifying the spring geometry to alter its stiffness and frequency characteristics. These changes result in separation of the natural and Strouhal frequencies. With an understanding of how springs respond in the flowing water environment, the spring physical parameters can be designed to avoid large amplitude vibration. (orig.)

Enhanced MR angiography of the lower extremities with synergy spine coil

International Nuclear Information System (INIS)

Takashima, Hiroyuki; Watanabe, Naoki

2002-01-01

A synergy spine coil is a phased-array coil designed for spine imaging. The coil's sensitive area is narrow in both the x-axis and y-axis directions but very wide in the z-axis direction. It is therefore suitable for using in long parts of the body, such as the spine. We used the coil for enhanced MR angiography in the lower extremities, which requires a very long field of view on the z-axis direction. Using on the NEMA (National Electrical Manufacturers Association) standard test for special-purpose coils, the sensitive volume of the synergy spine coil was first measured by using a phantom. It was found that the sensitive lengths along x-axis and y-axis were 300 mm and 120 mm, respectively, while that along z-axis could set at any length required for the examination by modifying the element number. The above area was confirmed to be sufficient for obtaining enhanced MR angiograms of the lower extremities. The results of this study showed the use of the synergy spine coil in enhanced MR angiography of the lower extremities is superior to the use of a conventional whole body coil for obtaining good MR angiograms with a good single-to-noise ratio (SNR). (author)

PDX toroidal field coils stress analysis

International Nuclear Information System (INIS)

Nikodem, Z.D.; Smith, R.A.

1975-01-01

A method used in the stress analysis of the PDX toroidal field coil is developed. A multilayer coil design of arbitrary dimensions in the shape of either a circle or an oval is considered. The analytical model of the coil and the supporting coil case with connections to the main support structure is analyzed using the finite element technique. The three dimensional magnetic fields and the non-uniform body forces which are a loading condition on a coil due to toroidal and poloidal fields are calculated. The method of analysis permits rapid and economic evaluations of design changes in coil geometry as well as in coil support structures. Some results pertinent to the design evolution and their comparison are discussed. The results of the detailed stress analysis of the final coil design due to toroidal field, poloidal field and temperature loads are presented

Analysis and test to predict the fatigue life of the ISX-B toroidal field coils' finger joints

International Nuclear Information System (INIS)

O'Toole, J.A.; Ojalvo, I.U.; Raynor, G.E.; Zatz, I.J.; Johnson, N.E.; Walls, J.C.; Nelson, B.E.; Cain, W.D.; Walstrom, P.L.; Pearce, J.W.

1979-01-01

A new and more rigorous structural evaluation of the ISX toroidal field (TF) coil fingers joints was undertaken to assess the effects of high-/beta/ operation of ISX-B. A new poloidal field (PF) coil set which allows high-/beta/ operation and produces larger out-of-plane loads on the TF coils was installed as part of the change to ISX-B. It was determined that the iron core significantly affects the out-of-plane load distribution and forces were calculated using the GFUN-3D code which considers 3-D iron core effects. These loads were applied to a half-symmetric finite element NASTRAN code model in which the TF coils were modeled as a string of beam elements. 8 refs

Study on the performance improvement of the high temperature superconducting coil with several separated coils at the edges

International Nuclear Information System (INIS)

Ishiguri, S.; Oka, T.; Fukui, S.; Ogawa, J.; Sato, T.

2008-01-01

In designing high temperature superconducting (HTS) coils, it is important to secure large magnetic fields and stored energy using shorter tape length. Thus, it is necessary to improve the transport current performance of the coils. The critical current and n-value of an HTS tape depend on magnetic fields and flux angles under constant temperature. Considering these dependencies, we established a model to analyze coil critical current. This model clarifies that relatively large electric fields are generated at the coil edges. This adversely affects the transport current performance. In this study, the coil edge is separated into several coils, keeping the total tape length constant. This increases the coil critical current, stored energy, central magnetic field, and also the coil volume, which contains vacancies created by the separation. To estimate coil performance, we calculated the stored energy density, whose denominator is the increased coil volume. This stored energy density reaches its maximum value when the number of the separated coils is eight. At this optimum separation, the central magnetic field increases by 13%, and the stored energy improves by 43%, compared to a rectangular coil wound with the same tape length

Toroidal simulation magnet tests

International Nuclear Information System (INIS)

Walstrom, P.L.; Domm, T.C.

1975-01-01

A number of different schemes for testing superconducting coils in a simulated tokamak environment are analyzed for their merits relative to a set of test criteria. Two of the concepts are examined in more detail: the so-called cluster test scheme, which employs two large background field coils, one on either side of the test coil, and the compact torus, a low-aspect ratio toroidal array of a small number of coils in which all of the coils are essentially test coils. Simulation of the pulsed fields of the tokamak is discussed briefly

COOLING COIL EFFECTS ON BLENDING IN A PILOT SCALE TANK

International Nuclear Information System (INIS)

Leishear, R.; Poirier, M.; Fowley, M.; Steeper, T.

2010-01-01

Blending, or mixing, processes in 1.3 million gallon nuclear waste tanks are complicated by the fact that miles of serpentine, vertical, cooling coils are installed in the tanks. As a step toward investigating blending interference due to coils in this type of tank, a 1/10.85 scale tank and pump model were constructed for pilot scale testing. A series of tests were performed in this scaled tank by adding blue dye to visualize blending, and by adding acid or base tracers to solution to quantify the time required to effectively blend the tank contents. The acid and base tests were monitored with pH probes, which were located in the pilot scale tank to ensure that representative samples were obtained. Using the probes, the hydronium ion concentration [H + ] was measured to ensure that a uniform concentration was obtained throughout the tank. As a result of pilot scale testing, a significantly improved understanding of mixing, or blending, in nuclear waste tanks has been achieved. Evaluation of test data showed that cooling coils in the waste tank model increased pilot scale blending times by 200% in the recommended operating range, compared to previous theoretical estimates of a 10-50% increase. Below the planned operating range, pilot scale blending times were increased by as much as 700% in a tank with coils installed. One pump, rather than two or more, was shown to effectively blend the tank contents, and dual pump nozzles installed parallel to the tank wall were shown to provide optimal blending. In short, experimental results varied significantly from expectations.

The normal zone propagation in ATLAS B00 model coil

CERN Document Server

Boxman, E W; ten Kate, H H J

2002-01-01

The B00 model coil has been successfully tested in the ATLAS Magnet Test Facility at CERN. The coil consists of two double pancakes wound with aluminum stabilized cables of the barrel- and end-cap toroids conductors for the ATLAS detector. The magnet current is applied up to 24 kA and quenches are induced by firing point heaters. The normal zone velocity is measured over a wide range of currents by using pickup coils, voltage taps and superconducting quench detectors. The signals coming from various sensors are presented and analyzed. The results extracted from the various detection methods are in good agreement. It is found that the characteristic velocities vary from 5 to 20 m/s at 15 and 24 kA respectively. In addition, the minimum quench energies at different applied magnet currents are presented. (6 refs).

Structural analysis of TFTR toroidal field coil conceptual design

International Nuclear Information System (INIS)

Smith, R.A.

1975-10-01

The conceptual design evaluation of the V-shaped toroidal field coils on the Tokamak Fusion Test Reactor has been performed by detailed structural analysis with the finite element method. The innovation provided by this design and verified in this work is the capability to support toroidal field loads while simultaneously performing the function of twist restraint against the device axial torques resulting from the vertical field loads. The evaluations made for the conceptual design provide predictions for coil deflections and stresses. The results are available for the separate effects from toroidal fields, poloidal fields, and the thermal expansion of the coils as well as for the superposition of the primary loads and the primary plus thermal loads

Liquid rope coiling

NARCIS (Netherlands)

Ribe, N.M.; Habibi, M.; Bonn, D.

2012-01-01

A thin stream or rope of viscous fluid falling from a sufficient height onto a surface forms a steadily rotating helical coil. Tabletop laboratory experiments in combination with a numerical model for slender liquid ropes reveal that finite-amplitude coiling can occur in four distinct regimes

Measurement of heating coil temperature for e-cigarettes with a “top-coil” clearomizer

Science.gov (United States)

Wang, Ping; Ito, Kazuhide; Fowles, Jeff; Shusterman, Dennis; Jaques, Peter A.; Kumagai, Kazukiyo

2018-01-01

Objectives To determine the effect of applied power settings, coil wetness conditions, and e-liquid compositions on the coil heating temperature for e-cigarettes with a “top-coil” clearomizer, and to make associations of coil conditions with emission of toxic carbonyl compounds by combining results herein with the literature. Methods The coil temperature of a second generation e-cigarette was measured at various applied power levels, coil conditions, and e-liquid compositions, including (1) measurements by thermocouple at three e-liquid fill levels (dry, wet-through-wick, and full-wet), three coil resistances (low, standard, and high), and four voltage settings (3–6 V) for multiple coils using propylene glycol (PG) as a test liquid; (2) measurements by thermocouple at additional degrees of coil wetness for a high resistance coil using PG; and (3) measurements by both thermocouple and infrared (IR) camera for high resistance coils using PG alone and a 1:1 (wt/wt) mixture of PG and glycerol (PG/GL). Results For single point thermocouple measurements with PG, coil temperatures ranged from 322 ‒ 1008°C, 145 ‒ 334°C, and 110 ‒ 185°C under dry, wet-through-wick, and full-wet conditions, respectively, for the total of 13 replaceable coil heads. For conditions measured with both a thermocouple and an IR camera, all thermocouple measurements were between the minimum and maximum across-coil IR camera measurements and equal to 74% ‒ 115% of the across-coil mean, depending on test conditions. The IR camera showed details of the non-uniform temperature distribution across heating coils. The large temperature variations under wet-through-wick conditions may explain the large variations in formaldehyde formation rate reported in the literature for such “top-coil” clearomizers. Conclusions This study established a simple and straight-forward protocol to systematically measure e-cigarette coil heating temperature under dry, wet-through-wick, and full

Development of a helical-coil double wall tube steam generator for 4S reactor

International Nuclear Information System (INIS)

Kitajima, Yuko; Maruyama, Shigeki; Jimbo, Noboru; Hino, Takehisa; Sato, Katsuhiko

2011-01-01

The 4S, Super-Safe Small and Simple, is a small-sized sodium-cooled fast reactor. A fast reactor usually uses sodium as a coolant to transfer heat from core to turbine/generator system. The heat of the intermediate heat transport system and that of the water stream systems are exchanged by the steam generator (SG) tubes. If the tube failure occurs, a sodium/water reaction could be occurred. To prevent the reaction and enhance safety, a helical-coil-type double wall tube with wire mesh interlayer and continuous monitoring systems of tube failure are applied to the SG of the 4S. The development and general features of this type double wall tube were described in Ref. 1) and Ref. 2). Those paper summarized following results; The tubes studied in these references were straight type. To establish this SG, development of manufacturing method of helical-coil-type double wall tube and validation of the tube failure monitoring system are needed. In this study, three demonstration tests have been performed; welding test of the double wall tube to manufacture the tubes with 70-80m length, assembling test of the helical-coil tube, and confirmation test of the tube processing system using the fabricated helical-coil tubes. As a result, following technologies have been successfully established. (1) Development of the welding techniques for manufacturing of the helical-coil-type double wall tube with wire mesh interlayer. (2) The confirmation test for manufacturing the helical coil tube of the SG. (author)

Cooling and dehumidifying coils

International Nuclear Information System (INIS)

Murthy, M.V.K.

1988-01-01

The operating features of cooling and dehumidifying coils and their constructional details are discussed. The heat transfer relations as applicable to the boiling refrigerant and a single phase fluid are presented. Methods of accounting for the effect of moisture condensation on the air side heat transfer coefficient and the fin effectiveness are explained. The logic flow necessary to analyze direct expansion coils and chilled water coils is discussed

Design and test program of a simplified divertor dummy coil structure for the WEST project

Energy Technology Data Exchange (ETDEWEB)

Doceul, L., E-mail: louis.doceul@cea.fr [CEA, IRFM, Saint-Paul-Lez-Durance Cedex F-13108 (France); Bucalossi, J.; Dougnac, H.; Ferlay, F.; Gargiulo, L.; Keller, D.; Larroque, S.; Lipa, M.; Pilia, A. [CEA, IRFM, Saint-Paul-Lez-Durance Cedex F-13108 (France); Portafaix, C. [ITER Organization, Route de Vinon-sur-Verdon 13115, St. Paul-lez-Durance (France); Saille, A. [CEA, IRFM, Saint-Paul-Lez-Durance Cedex F-13108 (France); Salami, M. [AVANTIS Engineering Groupe, ZI de l’Aiguille 46100, Figeac (France); Samaille, F.; Soler, B.; Thouvenin, D.; Verger, J.M.; Zago, B. [CEA, IRFM, Saint-Paul-Lez-Durance Cedex F-13108 (France)

2013-12-15

Highlights: • The mechanical design and integration of the divertor structure has been performed. • The design of the casing and the winding-pack has been finalized. • The coil assembly process has been validated. • The realization of a coil mock-up scale one is in progress. -- Abstract: In order to fully validate actively cooled tungsten plasma facing components (industrial fabrication, operation with long plasma duration), the implementation of a tungsten axisymmetric divertor structure in the tokamak Tore-Supra is studied. With this major upgrade, so-called WEST (Tungsten Environment in Steady state Tokamak), Tore-Supra will be able to address the problematic of long plasma discharges with a metallic divertor target. To do so, it is planned to install two symmetric divertor coils inside the vacuum vessel. This assembly, called divertor structure, is made up of two stainless steel casings containing a copper winding pack cooled by a pressurized hot water circuit (up to 180 °C, 4 MPa) and is designed to perform steady state plasma operation (up to 1000 s). The divertor structure will be a complex assembly ring of 4 m diameter representing a total weight of around 20 tons. The technical challenge of this component will be the implementation of angular sectors inside the vacuum vessel environment (TIG welding of the coil casing, induction brazing and electrical insulation of the copper winding). Moreover, this complex assembly must sustain harsh environmental conditions in terms of ultra high vacuum conditions, electromagnetical loads and electrical isolation (13 kV ground voltage) under high temperature. In order to fully validate the assembly and the performance of this complex component, the production of a scale one dummy coil is in progress. The paper will illustrate, the technical developments performed in order to finalize the design for the call for tender for fabrication. The progress and the first results of the simplified dummy coils will be also

Design and test program of a simplified divertor dummy coil structure for the WEST project

International Nuclear Information System (INIS)

Doceul, L.; Bucalossi, J.; Dougnac, H.; Ferlay, F.; Gargiulo, L.; Keller, D.; Larroque, S.; Lipa, M.; Pilia, A.; Portafaix, C.; Saille, A.; Salami, M.; Samaille, F.; Soler, B.; Thouvenin, D.; Verger, J.M.; Zago, B.

2013-01-01

Highlights: • The mechanical design and integration of the divertor structure has been performed. • The design of the casing and the winding-pack has been finalized. • The coil assembly process has been validated. • The realization of a coil mock-up scale one is in progress. -- Abstract: In order to fully validate actively cooled tungsten plasma facing components (industrial fabrication, operation with long plasma duration), the implementation of a tungsten axisymmetric divertor structure in the tokamak Tore-Supra is studied. With this major upgrade, so-called WEST (Tungsten Environment in Steady state Tokamak), Tore-Supra will be able to address the problematic of long plasma discharges with a metallic divertor target. To do so, it is planned to install two symmetric divertor coils inside the vacuum vessel. This assembly, called divertor structure, is made up of two stainless steel casings containing a copper winding pack cooled by a pressurized hot water circuit (up to 180 °C, 4 MPa) and is designed to perform steady state plasma operation (up to 1000 s). The divertor structure will be a complex assembly ring of 4 m diameter representing a total weight of around 20 tons. The technical challenge of this component will be the implementation of angular sectors inside the vacuum vessel environment (TIG welding of the coil casing, induction brazing and electrical insulation of the copper winding). Moreover, this complex assembly must sustain harsh environmental conditions in terms of ultra high vacuum conditions, electromagnetical loads and electrical isolation (13 kV ground voltage) under high temperature. In order to fully validate the assembly and the performance of this complex component, the production of a scale one dummy coil is in progress. The paper will illustrate, the technical developments performed in order to finalize the design for the call for tender for fabrication. The progress and the first results of the simplified dummy coils will be also

Voltage harmonic variation in three-phase induction motors with different coil pitches

International Nuclear Information System (INIS)

Deshmukh, Ram; Moses, Anthony John; Anayi, Fatih

2006-01-01

A pulse-width modulation (PWM) inverter feeding four different chorded three-phase induction motors was tested for low-order odd harmonic voltage component and efficiency at different loads. Total harmonic distortion (THD) due to 3rd, 5th and 9th harmonics was less in a motor with 160 o coil pitch. Particular harmonic order for each coil pitch was suppressed and the efficiency of a 120 o coil pitch motor was increased by 7.5%

Design of Nb3Sn Coils for LARP Long Magnets

International Nuclear Information System (INIS)

Ferracin, Paolo; Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Ferracin, P.; Caspi, S.; Lietzke, A. F.

2007-01-01

The LHC Accelerator Research Program (LARP) has a primary goal to develop, assemble, and test full size Nb 3 Sn quadrupole magnet models for a luminosity upgrade of the Large Hadron Collider (LHC). A major milestone in this development is to assemble and test, by the end of 2009, two 4 m-long quadrupole cold masses, which will be the first Nb 3 Sn accelerator magnet models approaching the length of real accelerator magnets. The design is based on the LARP Technological Quadrupoles (TQ), under development at FNAL and LBNL, with gradient higher than 200 T/m and aperture of 90 mm. The mechanical design will be chosen between two designs presently explored for the TQs: traditional collars and Al-shell based design (preloaded by bladders and keys). The fabrication of the first long quadrupole model is expected to start in the last quarter of 2007. Meanwhile the fabrication of 4 m-long racetrack coils started this year at BNL. These coils will be tested in an Al-shell based supporting structure developed at LBNL. Several challenges have to be addressed for the successful fabrication of long Nb 3 Sn coils. This paper presents these challenges with comments and solutions adopted or under study for these magnets. The coil design of these magnets, including conductor and insulation features, and quench protection studies are also presented

Design of Nb3Sn coils for LARP long magnets

International Nuclear Information System (INIS)

Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Dietderich, D.; Feher, S.; Ferracin, P.; Ghosh, A.; Gourlay, S.; Kashikhin, V.V.; Lietzke, A.; McInturff, A.; Muratore, J.; Nobrega, F.; Sabbi, G.L.; Schmalzle, J.; Wanderer, P.; Zlobin, A.V.; Fermilab; Brookhaven; LBL, Berkeley; Texas A-M

2006-01-01

The LHC Accelerator Research Program (LARP) has a primary goal to develop, assemble, and test full size Nb 3 Sn quadrupole magnet models for a luminosity upgrade of the Large Hadron Collider (LHC). A major milestone in this development is to assemble and test, by the end of 2009, two 4m-long quadrupole cold masses, which will be the first Nb3Sn accelerator magnet models approaching the length of real accelerator magnets. The design is based on the LARP Technological Quadrupoles (TQ), under development at FNAL and LBNL, with gradient higher than 200 T/m and aperture of 90 mm. The mechanical design will be chosen between two designs presently explored for the TQs: traditional collars and Al-shell based design (preloaded by bladders and keys). The fabrication of the first long quadrupole model is expected to start in the last quarter of 2007. Meanwhile the fabrication of 4m-long racetrack coils started this year at BNL. These coils will be tested in an Al-shell based supporting structure developed at LBNL. Several challenges have to be addressed for the successful fabrication of long Nb 3 Sn coils. This paper presents these challenges with comments and solutions adopted or under study for these magnets. The coil design of these magnets, including conductor and insulation features, and quench protection studies are also presented

Design, manufacture and performance of the JET Toroidal field coils

International Nuclear Information System (INIS)

Huguet, M.; Booth, J.; Pohlchen, R.

1983-01-01

The JET Toroidal field magnet compromises 32 D shaped coils each 5.7 m high, 3.8 wide and weighing 12 tonnes. The field produced is 3.45 Tesla at 2.9 m radius when operating at the maximum current of 66.5 kA. The coils are wound with water cooled hollow conductor and operate with an equivalent rectangular current pulse length of 20 seconds at full current. A description of the evolution of the design in relation to the constraints imposed is given first. These design constraints included the low aspect ratio of the Torus, the long pulse duration, the large mechanical forces and also the availability of suitable copper conductor sections. The stress analysis of the coil is outlined as well as the cooling requirements and some specific stresses. The construction of the D shaped coils in hard copper presents problems due to the spring back effect of the conductor. The methods adopted to solve these difficulties together with other problems related to the winding process are given. A large number of tests were carried out in order to establish the conditions necessary to obtain reliable brazed joints. During production the non destructive tests for each joint were very severe and included X-ray examination. In order to meet the JET delivery programme, a large effort has been required in terms of production tools and organization of the work at the supplier's works. This effort and the construction schedule is outlined. After assembly on the JET machine the TF coils have been tested and their initial performances in electrical, mechanical and thermal terms are compared with predicted values

Engineering development of an HTS floating coil for the Mini-RT project

International Nuclear Information System (INIS)

Yanagi, Nagato; Mito, Toshiyuki; Morikawa, Junji

2004-01-01

A magnetically-levitated superconducting coil device, Mini-RT, has been constructed using a high temperature superconductor (HTS) for the purpose of examining a new magnetic confinement scheme of high-beta non-neutral plasmas. The floating coil is wound with silver-sheathed Bi-2223 tapes, and it is operated in the temperature range of 20-40 K. A number of studies and experiments were carried out in order to realize the necessary system. One of them was to demonstrate magnetic levitation using a miniature HTS floating coil having a diameter of 80 mm. The coil was fabricated using Bi-2223/Ag tapes of 12 m and excited by field cooling with liquid nitrogen. The magnetic levitation was examined using a real-time feedback control system with laser displacement gauges. Additionally, a persistent current switch (PCS) has been developed using Bi-2223/Ag tapes of 21 m, and a prototype HTS-PCS was tested in a cryostat. After construction of the floating coil and HTS-PCS for the Mini-RT device was completed, excitation tests were carried out in the cryostat and the basic properties up to the nominal operation condition were examined. (author)

Analysis and experimental study of wireless power transfer with HTS coil and copper coil as the intermediate resonators system

International Nuclear Information System (INIS)

Wang, Xiufang; Nie, Xinyi; Liang, Yilang; Lu, Falong; Yan, Zhongming; Wang, Yu

2017-01-01

Highlights: • We investigated a kind of system architecture with three coils which the repeater is copper coil or HTS coil. • We simulated the different repeater system and obtained the magnetic field distribution at different distance. • We used helical coil instead of pancake coil which does not use capacitors. • HTS intermediate coil has significant effect on improving the transmission efficiency and lengthening transmission distance than copper intermediate coil. - Abstract: Intermediate resonator (repeater) between transmitter and receiver can significantly increase the distance of wireless power transfer (WPT) and the efficiency of wireless power transfer. The wireless power transfer via strongly coupled magnetic resonances with an high temperature superconducting (HTS) coil and copper coil as intermediate resonators was presented in this paper. The electromagnetic experiment system under different conditions with different repeating coils were simulated by finite element software. The spatial distribution patterns of magnetic induction intensity at different distances were plotted. In this paper, we examined transfer characteristics with HTS repeating coil and copper repeating coil at 77 K and 300 K, respectively. Simulation and experimental results show that HTS and copper repeating coil can effectively enhance the space magnetic induction intensity, which has significant effect on improving the transmission efficiency and lengthening transmission distance. We found that the efficiency and the distance of wireless power transfer system with an HTS coil as repeater is much higher by using of copper coil as repeater.

Analysis and experimental study of wireless power transfer with HTS coil and copper coil as the intermediate resonators system

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiufang [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); School of Physics and Technology, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Nie, Xinyi [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Liang, Yilang [School of Physics and Technology, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Lu, Falong [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Yan, Zhongming, E-mail: wangxiufanghappy@163.com [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Wang, Yu [School of Electrical Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China)

2017-01-15

Highlights: • We investigated a kind of system architecture with three coils which the repeater is copper coil or HTS coil. • We simulated the different repeater system and obtained the magnetic field distribution at different distance. • We used helical coil instead of pancake coil which does not use capacitors. • HTS intermediate coil has significant effect on improving the transmission efficiency and lengthening transmission distance than copper intermediate coil. - Abstract: Intermediate resonator (repeater) between transmitter and receiver can significantly increase the distance of wireless power transfer (WPT) and the efficiency of wireless power transfer. The wireless power transfer via strongly coupled magnetic resonances with an high temperature superconducting (HTS) coil and copper coil as intermediate resonators was presented in this paper. The electromagnetic experiment system under different conditions with different repeating coils were simulated by finite element software. The spatial distribution patterns of magnetic induction intensity at different distances were plotted. In this paper, we examined transfer characteristics with HTS repeating coil and copper repeating coil at 77 K and 300 K, respectively. Simulation and experimental results show that HTS and copper repeating coil can effectively enhance the space magnetic induction intensity, which has significant effect on improving the transmission efficiency and lengthening transmission distance. We found that the efficiency and the distance of wireless power transfer system with an HTS coil as repeater is much higher by using of copper coil as repeater.

Coil Design for High Misalignment Tolerant Inductive Power Transfer System for EV Charging

Directory of Open Access Journals (Sweden)

Kafeel Ahmed Kalwar

2016-11-01

Full Text Available The inductive power transfer (IPT system for electric vehicle (EV charging has acquired more research interest in its different facets. However, the misalignment tolerance between the charging coil (installed in the ground and pick-up coil (mounted on the car chassis, has been a challenge and fundamental interest in the future market of EVs. This paper proposes a new coil design QDQ (Quad D Quadrature that maintains the high coupling coefficient and efficient power transfer during reasonable misalignment. The QDQ design makes the use of four adjacent circular coils and one square coil, for both charging and pick-up side, to capture the maximum flux at any position. The coil design has been modeled in JMAG software for calculation of inductive parameters using the finite element method (FEM, and its hardware has been tested experimentally at various misaligned positions. The QDQ coils are shown to be capable of achieving good coupling coefficient and high efficiency of the system until the misalignment displacement reaches 50% of the employed coil size.

The energizing of a NMR superconducting coil by a superconducting rectifier

International Nuclear Information System (INIS)

Sikkenga, J.; ten Kate, H.H.J.; van der Klundert, L.J.M.; Knoben, J.; Kraaij, G.J.; Spuorenberg, C.J.G.

1985-01-01

NMR magnets require a good homogeneity within a certain volume and an excellent field stability. The homogeneity can be met using a superconducting shim coil system. The field stability requires a constant current, although in many cases the current decay time constant is too low, due to imperfections in the superconducting wire and joints. This can be overcome using a rectifier. The rectifier can also be used to load the coil. The combination and interaction of the superconducting NMR coil (2.0 Tesla and 0.35 m cold bore) and the rectifier (20 W / 1 kA) is tested. The safety of the system is discussed. The shim coil system can compensate the strayfield of the rectifier. The field decay compensation will be discussed

Analysis of quench in the NHMFL REBCO prototype coils for the 32 T Magnet Project

International Nuclear Information System (INIS)

Breschi, M; Cavallucci, L; Ribani, P L; Gavrilin, A V; Weijers, H W

2016-01-01

A 32 T all-superconductive magnet with high field REBCO inner coils is under development at the National High Magnetic Field Laboratory, Tallahassee, Florida, USA. As part of the development activity, two prototype coils with full scale radial dimensions and final design features, but with reduced axial length were constructed. The prototype coils consist of six dry-wound double pancakes modules with uninsulated conductor and insulated stainless steel cowind. Quench studies on one of the prototype coils at 4.2 K in self-field and in a background magnetic field of 15 T were performed by activating a set of quench protection heaters. In this paper, we present a numerical analysis of the experimental results of the quench tests of one of the prototype coils. The numerical analysis was carried out through a coupled electro-thermal FEM model developed at the University of Bologna. The model is based on the coupling with distributed contact resistances of the coil pancakes described as 2D elements. A homogenization procedure of the REBCO tape and other coil materials is presented, which allows reducing the number of degrees of freedom and the computational effort. The model is applied to the analysis of the current and voltage evolutions during the experimental quench tests on the prototype coil. (paper)

Applicability estimation of flowmeter logging for detecting hydraulic pass

International Nuclear Information System (INIS)

Miyakawa, Kimio; Tanaka, Yasuji; Tanaka, Kazuhiro

1997-01-01

Estimation of the hydraulic pass governing hydrogeological structure contributes significantly to the siting HLW repository. Flowmeter logging can detect hydraulic passes by measuring vertical flow velocity of groundwater in the borehole. We reviewed application of this logging in situ. The hydraulic pass was detected with combination of ambient flow logging, with pumping and/or injecting induced flow logging. This application showed that the flowmeter logging detected hydraulic passes conveniently and accurately compared with other hydraulic tests. Hydraulic conductivity by using flowmeter logging was assessed above 10 -6 m/sec and within one order from comparison with injection packer tests. We suggest that appropriate application of the flowmeter logging for the siting is conducted before hydraulic tests because test sections and monitoring sections are decided rationally for procurement of quantitative hydraulic data. (author)

A novel method for coil efficiency estimation: Validation with a 13C birdcage

DEFF Research Database (Denmark)

Giovannetti, Giulio; Frijia, Francesca; Hartwig, Valentina

2012-01-01

Coil efficiency, defined as the B1 magnetic field induced at a given point on the square root of supplied power P, is an important parameter that characterizes both the transmit and receive performance of the radiofrequency (RF) coil. Maximizing coil efficiency will maximize also the signal......-to-noise ratio. In this work, we propose a novel method for RF coil efficiency estimation based on the use of a perturbing loop. The proposed method consists of loading the coil with a known resistor by inductive coupling and measuring the quality factor with and without the load. We tested the method...... by measuring the efficiency of a 13C birdcage coil tuned at 32.13 MHz and verified its accuracy by comparing the results with the nuclear magnetic resonance nutation experiment. The method allows coil performance characterization in a short time and with great accuracy, and it can be used both on the bench...

Electrical Integrity Tests during Production of the LHC Dipoles

CERN Document Server

de Rijk, G; Cornelis, M; Fessia, P; Miles, J; Modena, M; Molinari, G; Rinn, J; Savary, F; Vlogaert, J

2006-01-01

For the LHC dipoles, mandatory electrical integrity tests are performed to qualify the cold mass (CM) at four production stages: individual pole, collared coil, CM before end cover welding and final CM. A description of the measurement equipment and its recent development are presented. After passing the demands set out in the specification, the results of the tests are transmitted to CERN where they are further analyzed. The paper presents the most important results of these measurements. We also report a review of the electrical non-conformities encountered e.g. interturn shorts and quench heater failure, their diagnostic and the cures.

Innovative mutually inductively coupled radiofrequency coils for magnetic resonance imaging and spectroscopy

International Nuclear Information System (INIS)

Tomanek, B.

2006-01-01

The paper presents the author's thesis based on the work carried out at the Institute for Bio diagnostics in Canada and published in years 2000-2006. A patented new generation of the RF coils were introduced to MRI and MRS techniques what significantly reduced SNR and improved image resolution of MR diagnostic procedure. Examples of the applications of the RF coils are presented. The intraoperative MRI system with a movable magnet used during the brain surgery included RF probe. This coil was efficiently used for breast screening and detection of submillimeter tumors. Quantification of the tissue metabolites by combining MRT with 31 P MRS can be achieved using dual - frequency RF coils. It was successfully tested on a rat liver. The innovative RF coil design was supported by the theoretical analysis and performed experiments. As an extension of the design an idea and the theory construction of multi - frequency multi - ring coil and its possible applications are also considered

Effect of γ-Al2O3/water nanofluid on the thermal performance of shell and coil heat exchanger with different coil torsions

Science.gov (United States)

Elshazly, K. M.; Sakr, R. Y.; Ali, R. K.; Salem, M. R.

2017-06-01

This work investigated experimentally the thermal performance of shell and coil heat exchanger with different coil torsions (λ) for γ-Al2O3/water nanofluid flow. Five helically coiled tube (HCT) with 0.0442 ≤ λ ≤ 0.1348 were tested within turbulent flow regime. The average size of γ-Al2O3 particles is 40 nm and volume concentration (φ) is varied from 0 to 2%. Results showed that reducing coil torsion enhances the heat transfer rate and increases HCT-friction factor (fc). Also, it is noticed that HCT average Nusselt number (Nut) and fc of nanofluids increase with increasing γ-Al2O3 volume concentration. The thermal performance index, TPI = (ht,nf/ht,bf)/(ΔPc,nf/ΔPc,bf). increases with increasing nanoparticles concentration, coil torsion, HCT-side inlet temperature and nanofluid flow rate. Over the studied range of HCT-Reynolds number, the average value of TPI is of 1.34 and 2.24 at φ = 0.5% and φ = 2%, respectively. The average value of TPI is of 1.64 at λ = 0.0442 while its average value at λ = 0.1348 is of 2.01. One of the main contributions is to provide heat equipments designers with Nut and fc correlations for practical configurations shell and coil heat exchangers with a wide range of nanofluid concentration.

Comparison of surface coil and knee coil for evaluation of the patellar cartilage by MR imaging

International Nuclear Information System (INIS)

Steen, M. van den; Maeseneer, M. de; Hoste, M.; Vanderdood, K.; Ridder, F. de; Osteaux, M.

2003-01-01

Purpose: The aim of this work was to compare the knee coil and the surface coil for the visualisation of the patellar cartilage. Materials and methods: In 28 patients (17 women, 11 men) with an average age of 40 years (range 14-76) with knee pain MR was performed. Transverse images were obtained using a fast spin echo proton density weighted sequence on a Philips Gyroscan Intera 1.5 T clinical system. Transverse images were obtained at the level of the patellar cartilage using both the surface and the knee coil. All images were evaluated by consensus of two radiologists. They evaluated a number of quality criteria on a 4-point scale. Criteria for artefacts were also graded on a 4-point scale. Results: For the visualisation of fluid there was no significant difference between the knee coil and the surface coil (P=0.021). For all other criteria regarding image quality and presence of imaging artefacts there was a significant difference between both coils (P<0.001) with the surface coil obtaining the better result. Conclusion: The use of the surface coil in the visualisation of the patellar cartilage can be recommended at knee MR

Structure of bacteriophage T4 fibritin: a segmented coiled coil and the role of the C-terminal domain.

Science.gov (United States)

Tao, Y; Strelkov, S V; Mesyanzhinov, V V; Rossmann, M G

1997-06-15

Oligomeric coiled-coil motifs are found in numerous protein structures; among them is fibritin, a structural protein of bacteriophage T4, which belongs to a class of chaperones that catalyze a specific phage-assembly process. Fibritin promotes the assembly of the long tail fibers and their subsequent attachment to the tail baseplate; it is also a sensing device that controls the retraction of the long tail fibers in adverse environments and, thus, prevents infection. The structure of fibritin had been predicted from sequence and biochemical analyses to be mainly a triple-helical coiled coil. The determination of its structure at atomic resolution was expected to give insights into the assembly process and biological function of fibritin, and the properties of modified coiled-coil structures in general. The three-dimensional structure of fibritin E, a deletion mutant of wild-type fibritin, was determined to 2.2 A resolution by X-ray crystallography. Three identical subunits of 119 amino acid residues form a trimeric parallel coiled-coil domain and a small globular C-terminal domain about a crystallographic threefold axis. The coiled-coil domain is divided into three segments that are separated by insertion loops. The C-terminal domain, which consists of 30 residues from each subunit, contains a beta-propeller-like structure with a hydrophobic interior. The residues within the C-terminal domain make extensive hydrophobic and some polar intersubunit interactions. This is consistent with the C-terminal domain being important for the correct assembly of fibritin, as shown earlier by mutational studies. Tight interactions between the C-terminal residues of adjacent subunits counteract the latent instability that is suggested by the structural properties of the coiled-coil segments. Trimerization is likely to begin with the formation of the C-terminal domain which subsequently initiates the assembly of the coiled coil. The interplay between the stabilizing effect of the C

High-resolution MR imaging of triangular fibrocartilage complex (TFCC): comparison of microscopy coils and a conventional small surface coil

Energy Technology Data Exchange (ETDEWEB)

Yoshioka, Hiroshi [Department of Radiology, University of Tsukuba, Tsukuba (Japan); Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, 02115, Boston, MA (United States); Ueno, Teruko; Itai, Yuji [Department of Radiology, University of Tsukuba, Tsukuba (Japan); Tanaka, Toshikazu [Department of Orthopedic Surgery, Tsukuba Kinen Hospital, Tsukuba (Japan); Shindo, Masashi [Tsukuba University Hospital, Tsukuba (Japan)

2003-10-01

To compare MR images of the triangular fibrocartilage complex (TFCC) using microscopy coils with those using a conventional surface coil qualitatively and quantitatively. Proton density-weighted images and T2*-weighted images of the TFCC from ten normal volunteers were obtained with a conventional surface coil (C4 coil; 80 mm in diameter), a 47-mm microscopy surface coil and a 23-mm microscopy surface coil at 1.5 T. Qualitative image analysis of MR images with three coils was performed by two radiologists who assigned one of five numerical scores (0, nonvisualization; 1, poor; 2, average; 3, good; 4, excellent) for five TFCC components, which were disc proper, triangular ligament, meniscus homologue, ulnotriquetral and ulnolunate ligament. Quantitative analysis included the signal-to-noise ratio (S/N) of the disc proper of TFCC, the lunate cartilage, the lunate bone and the contrast-noise-ratio (C/N) between articular cartilage and disc proper or bone marrow were measured. All structures show higher scores qualitatively on MR with microscopy coils than those with a C4 coil, and the difference was significant with the exception of the ulnolunate ligament. MR with microscopy coils showed significantly higher S/N values than those with a conventional surface coil (P<0.05 to P<0.001). T2*-weighted images using microscopy coils showed significantly higher cartilage-disc proper C/N and cartilage-bone marrow C/N (P<0.01 to P<0.001). On proton density-weighted images, the C/N between cartilage and disc proper with two microscopy coils was significantly higher (P<0.01) than that with a conventional coil. High-resolution MR images of the normal wrist using microscopy coils were superior to those using a conventional surface coil qualitatively and quantitatively. High-resolution MR imaging with a microscopy coil would be a promising method to diagnose TFCC lesions. (orig.)

Design of equilibrium field control coil system of TPE-RX

Energy Technology Data Exchange (ETDEWEB)

Sato, F.; Hasegawa, M.; Yamane, M.; Oyabu, I.; Urata, K.; Kudough, F. [Mitsubishi Fusion Center, Chiyoda-ku, Tokyo (Japan); Minato, T.; Kiryu, A.; Takagi, S.; Kuno, K.; Sako, K. [Mitsubishi Electric Corp. (Japan). Energy and Industrial Systems Center; Hirano, Y.; Yagi, Y.; Shimada, T.; Sekine, S.; Sakakita, H. [Electrotechnical Lab. (Japan)

1998-07-01

The construction of TPE-RX reversed field pinch(RFP) machine at the Electrotechnical Laboratory (ETL) was complete at the end of 1997 and the coil system showed the expected performances on the test at the ETL site. In the reversed field pinch machine, the plasma is surrounded by a thick metal shell to maintain plasma equilibrium and to obtain plasma stability. We designed the coil system considering an error magnetic field which is generated by an iron core and the poloidal shell gap of the thick shell. This paper describes designs and the related studies of the equilibrium field control coil system of TPE-RX. (author)

Design of equilibrium field control coil system of TPE-RX

International Nuclear Information System (INIS)

Sato, F.; Hasegawa, M.; Yamane, M.; Oyabu, I.; Urata, K.; Kudough, F.; Minato, T.; Kiryu, A.; Takagi, S.; Kuno, K.; Sako, K.

1998-01-01

The construction of TPE-RX reversed field pinch(RFP) machine at the Electrotechnical Laboratory (ETL) was complete at the end of 1997 and the coil system showed the expected performances on the test at the ETL site. In the reversed field pinch machine, the plasma is surrounded by a thick metal shell to maintain plasma equilibrium and to obtain plasma stability. We designed the coil system considering an error magnetic field which is generated by an iron core and the poloidal shell gap of the thick shell. This paper describes designs and the related studies of the equilibrium field control coil system of TPE-RX. (author)

Missense mutation in DISC1 C-terminal coiled-coil has GSK3β signaling and sex-dependent behavioral effects in mice

Science.gov (United States)

Dachtler, James; Elliott, Christina; Rodgers, R. John; Baillie, George S.; Clapcote, Steven J.

2016-01-01

Disrupted-in-Schizophrenia 1 (DISC1) is a risk factor for schizophrenia and affective disorders. The full-length DISC1 protein consists of an N-terminal ‘head’ domain and a C-terminal tail domain that contains several predicted coiled-coils, structural motifs involved in protein-protein interactions. To probe the in vivo effects of missense mutation of DISC1’s C-terminal tail, we tested mice carrying mutation D453G within a predicted α-helical coiled-coil region. We report that, relative to wild-type littermates, female DISC1D453G mice exhibited novelty-induced hyperlocomotion, an anxiogenic profile in the elevated plus-maze and open field tests, and reduced social exploration of unfamiliar mice. Male DISC1D453G mice displayed a deficit in passive avoidance, while neither males nor females exhibited any impairment in startle reactivity or prepulse inhibition. Whole brain homogenates showed normal levels of DISC1 protein, but decreased binding of DISC1 to GSK3β, decreased phospho-inhibition of GSK3β at serine 9, and decreased levels of β-catenin in DISC1D453G mice of either sex. Interrupted GSK3β signaling may thus be part of the mechanism underlying the behavioral phenotype associated with D453G, in common with the previously described N-terminal domain mutations Q31L and L100P in mice, and the schizophrenia risk-conferring variant R264Q in humans. PMID:26728762

Endovascular rescue method for undesirably stretched coil.

Science.gov (United States)

Cho, Jae Hoon

2014-10-01

Undesirable detachment or stretching of coils within the parent artery during aneurysm embolization can be related with thrombus formation, which can be caused occlusion of parent artery or embolic event(s). To escape from this situation, several rescue methods have been reported. A case with undesirably stretched coil in which another rescue method was used, is presented. When the stretched coil is still located in the coil delivery microcatheter, the stretched coil can be removed safely using a snare and a handmade monorail microcatheter. After a snare is lodged in the handmade monorail microcatheter, the snare is introduced over the coil delivery micorcatheter and located in the distal part of the stretched coil. After then, the handmade monorail microcatheter captures the stretched coil and the snare as one unit. This technique using a handmade monorail microcatheter and a snare can be a good rescue modality for the undesirably stretched coil, still remained within the coil delivery microcatheter.

A real-scale helical coil winding trial of the Large Helical Device

International Nuclear Information System (INIS)

Senba, T.; Yamamoto, T.; Tamaki, T.; Asano, K.; Suzuki, S.; Yamauchi, T.; Uchida, K.; Nakanishi, K.; Yamagiwa, T.; Suzuki, S.; Miyoshi, R.; Sasa, H.; Watanabe, S.; Tatemura, M.; Hatada, N.; Yamaguchi, S.; Imagawa, S.; Yanagi, N.; Satow, T.; Yamamoto, J.; Motojima, O.

1995-01-01

A real-scale helical coil winding trial of the Large Helical Device (LHD) has been conducted for a study of coil winding configuration and winding methods and for exhibiting the state of the art. It includes construction and test run of a specifically designed winding machine and development of various manufacturing methods for accurate coil winding. It has been carried out in Hitachi Works before in situ winding, and has provided much needed engineering data for construction of the LHD. (orig.)

A multi-slot surface coil for MRI of dual-rat imaging at 4 T

International Nuclear Information System (INIS)

Solis, S E; Rodriguez, A O; Wang, R; Tomasi, D

2011-01-01

A slotted surface coil inspired by the hole-and-slot cavity magnetron was developed for magnetic resonance imaging of obese rats at 4 T. Full-wave analysis of the magnetic field was carried out at 170 MHz for both the slotted and circular-shaped coils. The noise figure values of two coils were investigated via the numerical calculation of the quality factors. Fat simulated phantoms to mimic overweight rats were included in the analysis with weights ranging from 300 to 900 g. The noise figures were 1.2 dB for the slotted coil and 2.4 dB for the circular coil when loaded with 600 g of simulated phantom. A slotted surface coil with eight circular slots and a circular coil with similar dimensions were built and operated in the transceiver mode, and their performances were experimentally compared. The imaging tests in phantoms demonstrated that the slotted surface coil has a deeper RF-sensitivity and better field uniformity than the single-loop RF-coil. High quality images of two overweight Zucker rats were acquired simultaneously with the slotted surface coil using standard spin-echo pulse sequences. Experimental results showed that the slotted surface coil outperformed the circular coil for imaging considerably overweight rats. Thus, the slotted surface coil can be a good tool for MRI experiments in rats on a human whole-body 4 T scanner.

A multi-slot surface coil for MRI of dual-rat imaging at 4T

Energy Technology Data Exchange (ETDEWEB)

Solis, S.E.; Tomasi, D.; Solis, S.E.; Wang, R.; Tomasi, D.; Rodriguez, A.O.

2011-07-01

A slotted surface coil inspired by the hole-and-slot cavity magnetron was developed for magnetic resonance imaging of obese rats at 4 T. Full-wave analysis of the magnetic field was carried out at 170 MHz for both the slotted and circular-shaped coils. The noise figure values of two coils were investigated via the numerical calculation of the quality factors. Fat simulated phantoms to mimic overweight rats were included in the analysis with weights ranging from 300 to 900 g. The noise figures were 1.2 dB for the slotted coil and 2.4 dB for the circular coil when loaded with 600 g of simulated phantom. A slotted surface coil with eight circular slots and a circular coil with similar dimensions were built and operated in the transceiver mode, and their performances were experimentally compared. The imaging tests in phantoms demonstrated that the slotted surface coil has a deeper RF-sensitivity and better field uniformity than the single-loop RF-coil. High quality images of two overweight Zucker rats were acquired simultaneously with the slotted surface coil using standard spin-echo pulse sequences. Experimental results showed that the slotted surface coil outperformed the circular coil for imaging considerably overweight rats. Thus, the slotted surface coil can be a good tool for MRI experiments in rats on a human whole-body 4 T scanner.

A multi-slot surface coil for MRI of dual-rat imaging at 4 T

Energy Technology Data Exchange (ETDEWEB)

Solis, S E; Rodriguez, A O [Departamento de Ingenieria Electrica, Universidad Autonoma Metropolitana Iztapalapa, Mexico, DF 09340 (Mexico); Wang, R; Tomasi, D, E-mail: arog@xanum.uam.mx [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2011-06-21

A slotted surface coil inspired by the hole-and-slot cavity magnetron was developed for magnetic resonance imaging of obese rats at 4 T. Full-wave analysis of the magnetic field was carried out at 170 MHz for both the slotted and circular-shaped coils. The noise figure values of two coils were investigated via the numerical calculation of the quality factors. Fat simulated phantoms to mimic overweight rats were included in the analysis with weights ranging from 300 to 900 g. The noise figures were 1.2 dB for the slotted coil and 2.4 dB for the circular coil when loaded with 600 g of simulated phantom. A slotted surface coil with eight circular slots and a circular coil with similar dimensions were built and operated in the transceiver mode, and their performances were experimentally compared. The imaging tests in phantoms demonstrated that the slotted surface coil has a deeper RF-sensitivity and better field uniformity than the single-loop RF-coil. High quality images of two overweight Zucker rats were acquired simultaneously with the slotted surface coil using standard spin-echo pulse sequences. Experimental results showed that the slotted surface coil outperformed the circular coil for imaging considerably overweight rats. Thus, the slotted surface coil can be a good tool for MRI experiments in rats on a human whole-body 4 T scanner.

Use of a High-Temperature Superconducting Coil for Magnetic Energy Storage

International Nuclear Information System (INIS)

Fagnard, J-F; Crate, D; Jamoye, J-F; Laurent, Ph; Mattivi, B; Cloots, R; Ausloos, M; Genon, A; Vanderbemden, Ph

2006-01-01

A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing temperatures down to 17.2 K to be achieved. The temperature dependence of coil electrical resistance R(T) shows a superconducting transition at T = 102.5 K. Measurements of the V(I) characteristics were performed at several temperatures between 17.2 K and 101.5 K to obtain the temperature dependence of the critical current (using a 1 μV/cm criterion). Critical currents were found to exceed 100 A for T < 30 K. An electronic DC-DC converter was built in order to control the energy flow in and out of the superconducting coil. The converter consists of a MOS transistor bridge switching at a 80 kHz frequency and controlled with standard Pulse Width Modulation (PWM) techniques. The system was tested using a 30 V squared wave power supply as bridge input voltage. The coil current, the bridge input and output voltages were recorded simultaneously. Using a 10 A setpoint current in the superconducting coil, the whole system (coil + DC-DC converter) can provide a stable output voltage showing uninterruptible power supply (UPS) capabilities over 1 s

An experimental evaluation of multi-pass solar air heaters

Energy Technology Data Exchange (ETDEWEB)

Satcunanathan, S.; Persad, P.

1980-12-01

Three collectors of identical dimensions but operating in the single-pass, two-pass and three-pass modes were tested simultaneously under ambient conditions. It was found that the two-pass air heater was consistently better than the single-pass air heater over the day for the range of mass flow rates considered. It was also found that at a mass flow rate of 0.0095 kg s/sup -1/ m/sup -2/, the thermal performances of the two-pass and three-pass collectors were identical, but at higher flow rates the two-pass collector was superior to the three-pass collector, the superiority decreasing with increasing mass flow rate.

Nb3Sn accelerator magnet technology scale up using cos-theta dipole coils

Energy Technology Data Exchange (ETDEWEB)

Nobrega, F.; Andreev, N.; Ambrosio, G.; Barzi, E.; Bossert, R.; Carcagno, R.; Chlachidze, G.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; /Fermilab

2007-06-01

Fermilab is working on the development of Nb{sub 3}Sn accelerator magnets using shell-type dipole coils and the wind-and-react method. As a part of the first phase of technology development, Fermilab built and tested six 1 m long dipole model magnets and several dipole mirror configurations. The last three dipoles and two mirrors reached their design fields of 10-11 T. The technology scale up phase has started by building 2 m and 4 m dipole coils and testing them in a mirror configuration in which one of the two coils is replaced by a half-cylinder made of low carbon steel. This approach allows for shorter fabrication times and extensive instrumentation preserving almost the same level of magnetic field and Lorentz forces in the coils as in a complete dipole model magnet. This paper presents details on the 2 m (HFDM07) and 4 m long (HFDM08) Nb{sub 3}Sn dipole mirror magnet design and fabrication technology, as well as the magnet test results which are compared with 1 m long models.

Nb3Sn accelerator magnet technology scale up using cos-theta dipole coils

International Nuclear Information System (INIS)

Nobrega, F.; Andreev, N.; Ambrosio, G.; Barzi, E.; Bossert, R.; Carcagno, R.; Chlachidze, G.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Fermilab

2007-01-01

Fermilab is working on the development of Nb 3 Sn accelerator magnets using shell-type dipole coils and the wind-and-react method. As a part of the first phase of technology development, Fermilab built and tested six 1 m long dipole model magnets and several dipole mirror configurations. The last three dipoles and two mirrors reached their design fields of 10-11 T. The technology scale up phase has started by building 2 m and 4 m dipole coils and testing them in a mirror configuration in which one of the two coils is replaced by a half-cylinder made of low carbon steel. This approach allows for shorter fabrication times and extensive instrumentation preserving almost the same level of magnetic field and Lorentz forces in the coils as in a complete dipole model magnet. This paper presents details on the 2 m (HFDM07) and 4 m long (HFDM08) Nb 3 Sn dipole mirror magnet design and fabrication technology, as well as the magnet test results which are compared with 1 m long models

The JET divertor coil

International Nuclear Information System (INIS)

Last, J.R.; Froger, C.; Sborchia, C.

1989-01-01

The divertor coil is mounted inside the Jet vacuum vessel and is able to carry 1 MA turns. It is of conventional construction - water cooled copper, epoxy glass insulation -and is contained in a thin stainless steel case. The coil has to be assembled, insulated and encased inside the Jet vacuum vessel. A description of the coil is given, together with technical information (including mechanical effects on the vacuum vessel), an outline of the manufacture process and a time schedule. (author)

MRI with microscopy coil of the proximal interphalangeal joints: preliminary study

International Nuclear Information System (INIS)

Liu Min; Sun Haixing; Liu Dimin; Hu Meiyu; Pan Shunping; Wang Ping; Huang Xiaoling; Men Quanfei; Chen Yingming

2009-01-01

Objective: To investigate the use of a microscopy coil in MR examination of proximal interphalangeal joints (PIJ) to collect evidence on micro-anatomical pathological changes for further MR diagnosis. Methods: Four PIJ in cadaver and 12 PIJ from 7 normal volunteers were scanned with a microscopy surface coil (23 mm in diameter) at 1.5 T MRI. Sagittal T 1 -weighted images were also obtained with a conventional surface coil using the same parameters for the volunteers. Based on the observation of sagittal, traverse, coronal PIJ imaging features of cadaver, the optimized sequences were chosen for the volunteer's application. Image quality of the PIJ structures from volunteers was analyzed by two radiologists on a 5-point scale (0, nonvisualization; 1, poor; 2, average; 3, good; 4, excellent) and compared with Wilcoxon signed tank test between the microscopy and C3 surface coil in sagittal direction. Results: With microscopy coil all sequences can visualize the main structures of PI J, and all the PIJ images were classified as good or excellent except for one as average, while all the 12 PIJ with C3 coil were classified as poor or invisible. PIJ structures (proximal phalanx head, middle phalanx base, cartilage, volar plate) from volunteers show higher scores of quality with microscopy coils than those with C3 coil, and the difference was significant (Z =-3.274, -3.274, -3.213, and -3.742 respectively, all P<0.01). Conclusion: High-resolution MRI of the normal PIJ with microscopy coil was superior to those with a conventional surface coil, and it can be a promising method to diagnose interphalangeal joints lesions. (authors)

Borehole induction coil transmitter

Science.gov (United States)

Holladay, Gale; Wilt, Michael J.

2002-01-01

A borehole induction coil transmitter which is a part of a cross-borehole electromagnetic field system that is used for underground imaging applications. The transmitter consists of four major parts: 1) a wound ferrite or mu-metal core, 2) an array of tuning capacitors, 3) a current driver circuit board, and 4) a flux monitor. The core is wound with several hundred turns of wire and connected in series with the capacitor array, to produce a tuned coil. This tuned coil uses internal circuitry to generate sinusoidal signals that are transmitted through the earth to a receiver coil in another borehole. The transmitter can operate at frequencies from 1-200 kHz and supplies sufficient power to permit the field system to operate in boreholes separated by up to 400 meters.

A history of detachable coils: 1987-2012.

Science.gov (United States)

Hui, Ferdinand K; Fiorella, David; Masaryk, Thomas J; Rasmussen, Peter A; Dion, Jacques E

2014-03-01

The development of detachable coils is one of the most pivotal developments in neurointervention, providing a tool that could be used to treat a wide variety of hemorrhagic stroke. From the original Guglielmi detachable coil, a number of different coil designs and delivery designs have evolved. This article reviews the history of commercially available detachable coils. A timeline of detachable coils was constructed and coil design philosophies were reviewed. A complete list of commercially available coils is presented in a timeline format. Detachable coil technology continues to evolve. Advances in construction and design have yielded products which may benefit patients in terms of safety, radiation dose reduction and cost of treatment. Continued evolution is expected, irrespective of competing disruptive technologies.

Superconducting poloidal coils for STARFIRE commercial reactor

International Nuclear Information System (INIS)

Wang, S.T.; Evans, K. Jr.; Turner, L.R.; Huang, Y.C.; Prater, R.; Alcorn, J.

1979-01-01

STARFIRE is considered to be the tenth commercial tokamak power plant. A preliminary design study on its superconducting poloidal coil system is presented. Key features of the design studies are: the elimination of the ohmic heating coil; the trade-off studies of the equilibrium field coil locations; and the development of a conceptual design for the superconducting equilibrium field coils. Described are the 100 kA cryostable conductor design, the coil structure, and evaluation of the coil forces

Strong contributions from vertical triads to helix-partner preferences in parallel coiled coils.

Science.gov (United States)

Steinkruger, Jay D; Bartlett, Gail J; Woolfson, Derek N; Gellman, Samuel H

2012-09-26

Pairing preferences in heterodimeric coiled coils are determined by complementarities among side chains that pack against one another at the helix-helix interface. However, relationships between dimer stability and interfacial residue identity are not fully understood. In the context of the "knobs-into-holes" (KIH) packing pattern, one can identify two classes of interactions between side chains from different helices: "lateral", in which a line connecting the adjacent side chains is perpendicular to the helix axes, and "vertical", in which the connecting line is parallel to the helix axes. We have previously analyzed vertical interactions in antiparallel coiled coils and found that one type of triad constellation (a'-a-a') exerts a strong effect on pairing preferences, while the other type of triad (d'-d-d') has relatively little impact on pairing tendencies. Here, we ask whether vertical interactions (d'-a-d') influence pairing in parallel coiled-coil dimers. Our results indicate that vertical interactions can exert a substantial impact on pairing specificity, and that the influence of the d'-a-d' triad depends on the lateral a' contact within the local KIH motif. Structure-informed bioinformatic analyses of protein sequences reveal trends consistent with the thermodynamic data derived from our experimental model system in suggesting that heterotriads involving Leu and Ile are preferred over homotriads involving Leu and Ile.

Invited review the coiled coil silk of bees, ants, and hornets.

Science.gov (United States)

Sutherland, Tara D; Weisman, Sarah; Walker, Andrew A; Mudie, Stephen T

2012-06-01

In this article, we review current knowledge about the silk produced by the larvae of bees, ants, and hornets [Apoidea and Vespoidea: Hymenoptera]. Different species use the silk either alone or in composites for a variety of purposes including mechanical reinforcement, thermal regulation, or humidification. The characteristic molecular structure of this silk is α-helical proteins assembled into tetrameric coiled coils. Gene sequences from seven species are available, and each species possesses a copy of each of four related silk genes that encode proteins predicted to form coiled coils. The proteins are ordered at multiple length scales within the labial gland of the final larval instar before spinning. The insects control the morphology of the silk during spinning to produce either fibers or sheets. The silk proteins are small and non repetitive and have been produced artificially at high levels by fermentation in E. coli. The artificial silk proteins can be fabricated into materials with structural and mechanical properties similar to those of native silks. Copyright © 2011 Wiley Periodicals, Inc.

Self-Assembly of Rod-Coil Block Copolymers

National Research Council Canada - National Science Library

Jenekhe, S

1999-01-01

... the self-assembly of new rod-coil diblock, rod- coil-rod triblock, and coil-rod-coil triblock copolymers from solution and the resulting discrete and periodic mesostmctares with sizes in the 100...

Nb3Sn accelerator magnet technology scale up based on cos-theta coils

International Nuclear Information System (INIS)

Nobrega, F.; Ambrosio, G.; Andreev, N.; Barzi, E.; Bossert, R.; Carcagno, R.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Novitski, I.; Pischalnikov, Yu.; Sylvester, C.; Tartaglia, M.; Turrioni, D.; Yamada, R.; Zlobin, A.V.; Fermilab

2006-01-01

After successful testing of a 1 m long dipole mirror magnet and three dipole models based on two-layer Nb 3 Sn coils, Fermilab has started a Nb 3 Sn technology scale-up program using the dipole mirror design and the developed Nb 3 Sn coil fabrication technology based on the wind-and-react method. The scale-up will be performed in several steps starting from a 2 m long coil made of Powder-in-Tube (PIT) strand. This will be followed by 4 m long Nb 3 Sn coils made of PIT and RRP strands that will be fabricated into dipole mirror magnets and tested. This paper presents a summary of Fermilab's wind-and-react short model program. It includes details on the 2 m and 4 m long, 2 layer Nb 3 Sn dipole mirror magnet design, mechanical structure, and fabrication infrastructure

Nb3Sn accelerator magnet technology scale up based on cos-theta coils

Energy Technology Data Exchange (ETDEWEB)

Nobrega, F.; Ambrosio, G.; Andreev, N.; Barzi, E.; Bossert, R.; Carcagno, R.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Novitski, I.; Pischalnikov, Yu.; Sylvester, C.; Tartaglia, M.; Turrioni, D.; Yamada, R.; Zlobin, A.V.; /Fermilab

2006-08-01

After successful testing of a 1 m long dipole mirror magnet and three dipole models based on two-layer Nb{sub 3}Sn coils, Fermilab has started a Nb{sub 3}Sn technology scale-up program using the dipole mirror design and the developed Nb{sub 3}Sn coil fabrication technology based on the wind-and-react method. The scale-up will be performed in several steps starting from a 2 m long coil made of Powder-in-Tube (PIT) strand. This will be followed by 4 m long Nb{sub 3}Sn coils made of PIT and RRP strands that will be fabricated into dipole mirror magnets and tested. This paper presents a summary of Fermilab's wind-and-react short model program. It includes details on the 2 m and 4 m long, 2 layer Nb{sub 3}Sn dipole mirror magnet design, mechanical structure, and fabrication infrastructure.

A Built for Purpose Micro-Hole Coiled Tubing Rig (MCTR)

Energy Technology Data Exchange (ETDEWEB)

Bart Patton

2007-09-30

This report will serve as the final report on the work performed from the contract period October 2005 thru April 2007. The project 'A Built for Purpose Microhole Coiled Tubing Rig (MCTR)' purpose was to upgrade an existing state-of-the-art Coiled Tubing Drilling Rig to a Microhole Coiled Tubing Rig (MCTR) capable of meeting the specifications and tasks of the Department of Energy. The individual tasks outlined to meet the Department of Energy's specifications are: (1) Concept and development of lubricator and tool deployment system; (2) Concept and development of process control and data acquisition; (3) Concept and development of safety and efficiency improvements; and (4) Final unit integration and testing. The end result of the MCTR upgrade has produced a unit capable of meeting the following requirements: (1) Capable of handling 1-inch through 2-3/8-inch coiled tubing (Currently dressed for 2-3/8-inch coiled tubing and capable of running up to 3-1/2-inch coiled tubing); (2) Capable of drilling and casing surface, intermediate, production and liner hole intervals; (3) Capable of drilling with coiled tubing and has all controls and installation piping for a top drive; (4) Rig is capable of running 7-5/8-inch range 2 casing; and (5) Capable of drilling 5,000 ft true vertical depth (TVD) and 6,000 ft true measured depth (TMD).

Fabrication of new joints for SST-1 TF coil winding packs

International Nuclear Information System (INIS)

Prasad, Upendra; Sharma, A.N.; Patel, Dipak; Doshi, Kalpesh; Khristi, Yohan; Varmora, Pankaj; Chauhan, Pradeep; Jadeja, S.J.; Gupta, Pratibha; Pradhan, S.

2013-01-01

Highlights: • We have carried out work related with sub-nanoohm joints for superconducting Tokamak winding packs. • We have established fine tune QA/QC procedures for sub-nanoohm joints fabrication. • We have optimised welding parameters for cable in conduit conductors for fusion relevant magnets. • We have established precised measurement data acquisition system for low resistance measurements at cryogenic temperature. -- Abstract: The Toroidal Field (TF) magnet system of SST-1 has sixteen NbTi/Cu based coils with about one hundred Inter-Pancake (IP) and Inter-Coil (IC) joints. New box type helium leak tight, low DC resistance joints have been designed, fabricated and tested at 5 K temperature and 10 kA DC transport current. The prototype of this joint has been validated in laboratory as well as on spare TF coil winding pack. Moreover, the performance of these joints has been realised and validated on actual sixteen TF winding packs, the joint resistance of ∼0.5 nΩ repeatedly measured on hundreds of IP joints. The quality of terminations and joints was ensured at various stages of fabrication. The quality of joint box material was ensured by visual inspection, chemical analysis, radiography test, ultrasonic test, eddy current test, etc. This paper describes joint design drivers, joint design detail, prototype joint fabrication processes, quality assurance (QA)/quality control (QC) adopted during prototype and actual joint fabrication process, joint resistance measurement on actual TF coils and analysis of measured joint resistance in detail

ITER central solenoid model coil heat treatment complete and assembly started

International Nuclear Information System (INIS)

Thome, R.J.; Okuno, K.

1998-01-01

A major R and D task in the ITER program is to fabricate a Superconducting Model Coil for the Central Solenoid to establish the design and fabrication methods for ITER size coils and to demonstrate conductor performance. Completion of its components is expected in 1998, to be followed by assembly with structural components and testing in a facility at JAERI

Commissioning and Testing the 1970's Era LASS Solenoid Magnet in JLab's Hall D

Energy Technology Data Exchange (ETDEWEB)

Ballard, Joshua T. [Jefferson Lab, Newport News, VA; Biallas, George H. [Jefferson Lab, Newport News, VA; Brown, G.; Butler, David E. [Jefferson Lab, Newport News, VA; Carstens, Thomas J. [Jefferson Lab, Newport News, VA; Chudakov, Eugene A. [Jefferson Lab, Newport News, VA; Creel, Jonathan D. [Jefferson Lab, Newport News, VA; Egiyan, Hovanes [Jefferson Lab, Newport News, VA; Martin, F.; Qiang, Yi [Jefferson Lab, Newport News, VA; Smith, Elton S. [Jefferson Lab, Newport News, VA; Stevens, Mark A. [Jefferson Lab, Newport News, VA; Spiegel, Scot L. [Jefferson Lab, Newport News, VA; Whitlatch, Timothy E. [Jefferson Lab, Newport News, VA; Wolin, Elliott J. [Carnegie Mellon University , Pittsburgh, PA; Ghoshal, Probir K. [Jefferson Lab, Newport News, VA

2015-06-01

JLab refurbished and reconfigured the LASS1, 1.85m bore Solenoid and installed it as the principal analysis magnet for nuclear physics in the newly constructed, Hall D at Jefferson Lab. The magnet contains four superconducting coils within an iron yoke. The magnet was built in the early1970's at Stanford Linear Accelerator Center and used a second time at Los Alamos National Laboratory. The coils were extensively refurbished and individually tested by JLab. A new Cryogenic Distribution Box provides cryogens and their control valving, current distribution bus, and instrumentation pass-through. A repurposed CTI 2800 refrigerator system and new transfer line complete the system. We describe the re-configuration, the process and problems of re-commissioning the magnet and the results of testing the completed magnet.

GBNV encoded movement protein (NSm) remodels ER network via C-terminal coiled coil domain

Energy Technology Data Exchange (ETDEWEB)

Singh, Pratibha; Savithri, H.S., E-mail: bchss@biochem.iisc.ernet.in

2015-08-15

Plant viruses exploit the host machinery for targeting the viral genome–movement protein complex to plasmodesmata (PD). The mechanism by which the non-structural protein m (NSm) of Groundnut bud necrosis virus (GBNV) is targeted to PD was investigated using Agrobacterium mediated transient expression of NSm and its fusion proteins in Nicotiana benthamiana. GFP:NSm formed punctuate structures that colocalized with mCherry:plasmodesmata localized protein 1a (PDLP 1a) confirming that GBNV NSm localizes to PD. Unlike in other movement proteins, the C-terminal coiled coil domain of GBNV NSm was shown to be involved in the localization of NSm to PD, as deletion of this domain resulted in the cytoplasmic localization of NSm. Treatment with Brefeldin A demonstrated the role of ER in targeting GFP NSm to PD. Furthermore, mCherry:NSm co-localized with ER–GFP (endoplasmic reticulum targeting peptide (HDEL peptide fused with GFP). Co-expression of NSm with ER–GFP showed that the ER-network was transformed into vesicles indicating that NSm interacts with ER and remodels it. Mutations in the conserved hydrophobic region of NSm (residues 130–138) did not abolish the formation of vesicles. Additionally, the conserved prolines at positions 140 and 142 were found to be essential for targeting the vesicles to the cell membrane. Further, systematic deletion of amino acid residues from N- and C-terminus demonstrated that N-terminal 203 amino acids are dispensable for the vesicle formation. On the other hand, the C-terminal coiled coil domain when expressed alone could also form vesicles. These results suggest that GBNV NSm remodels the ER network by forming vesicles via its interaction through the C-terminal coiled coil domain. Interestingly, NSm interacts with NP in vitro and coexpression of these two proteins in planta resulted in the relocalization of NP to PD and this relocalization was abolished when the N-terminal unfolded region of NSm was deleted. Thus, the NSm

Development of quench protection system for HTS coils by active power method

International Nuclear Information System (INIS)

Nanato, N.; Tsumiyama, Y.; Kim, S.B.; Murase, S.; Seong, K.-C.; Kim, H.-J.

2007-01-01

Recently, HTS coils have been developed for electric power apparatuses. In superconducting coils, local and excessive joule heating may give damage to the superconducting windings when a quench occurs and therefore it is essential that the quench is detected quickly and precisely so that the coils can be safely discharged. Resistive voltage measurement method is universally used for the quench detection, however, it is vulnerable to an electromagnetic noise which causes insufficient quench detection and at least needs a central voltage tap in windings. In a large superconducting coil, a lead-wire from the central voltage tap may cause a short-circuit when high voltage will be applied. In this paper, we present a quench protection system based on the active power method which detects a quench by measuring the instantaneous active power generated in a superconducting coil. The protection system based on this method is very strong against to the noise and no more needs a central voltage tap. The performance of system developed by us is confirmed by using test coil wound with Bi-2223 HTS tapes

Boiling heat transfer and dryout in helically coiled tubes under different pressure conditions

International Nuclear Information System (INIS)

Chung, Young-Jong; Bae, Kyoo-Hwan; Kim, Keung Koo; Lee, Won-Jae

2014-01-01

Highlights: • Heat transfer characteristics and dryout for helically coiled tube are performed. • A boiling heat transfer tends to increase with a pressure increase. • Dryout occurs at high quality test conditions investigated. • Steiner–Taborek’s correlation is predicted well based on the experimental results. - Abstract: A helically coiled once-through steam generator has been used widely during the past several decades for small nuclear power reactors. The heat transfer characteristics and dryout conditions are important to optimal design a helically coiled steam generator. Various experiments with the helically coiled tubes are performed to investigate the heat transfer characteristics and occurrence condition of a dryout. For the investigated experimental conditions, Steiner–Taborek’s correlation is predicted reasonably based on the experimental results. The pressure effect is important for the boiling heat transfer correlation. A boiling heat transfer tends to increase with a pressure increase. However, it is not affected by the pressure change at a low power and low mass flow rate. Dryout occurs at high quality test conditions investigated because a liquid film on the wall exists owing to a centrifugal force of the helical coil

Synthesis, model and stability of helically coiled carbon nanotubes

DEFF Research Database (Denmark)

Fejes, Dora; Raffai, Manuella; Hernadi, Klara

2013-01-01

. Our experiments focused on the production and development of catalysts for the synthesis of helically coiled CNTs (carbon nanotubes). The catalysts were tested in the decomposition of acetylene by CCVD (Catalytic Chemical Vapor Deposition) method. The carbon deposit was imaged by TEM (Transmission......Structural model of helically coiled carbon nanotubes is proposed. It is constructed by means of topological coordinate method. Relaxation and cohesive energy calculation are performed by molecular mechanics, using second-generation bond order potential for hydrocarbons introduced by D. W. Brenner...

The Calculated and Measured Resistance for Splices between Conductors in a MICE Superconducting Coil

International Nuclear Information System (INIS)

Green, Michael A.; Dietderich, Dan; Higley, Hugh; Pan, Heng; Tam, Darren; Trillaud, Federic; Wang, Li; Wu, Hong; Xu, Feng Yu

2009-01-01

The resistance of superconducting joints within MICE coils is an important issue particularly for the coupling coils. The MICE tracker solenoids have only two superconducting joints in the three spectrometer set (end coil 1, the center coil and end coil 2). The AFC magnets may have only a single joint within the coil. The coupling coils may have as many as fifteen joints within the coil, due to relatively short piece lengths of the superconductor. LBNL and ICST looked at three types of coil joints. They are: (1) cold fusion butt joints, (2) side-by-side lap joints, and (3) up-down lap joints. A theoretical calculation of the joint resistance was done at LBNL and checked by ICST. After looking at the theoretical resistance of the three types of joints, it was decided that the cold welded butt joint was not an attractive alternative for joints within a MICE superconducting magnet coil. Side-by-side and up-down lap joints were fabricated at ICST using two types of soft solder between the conductors. These conductor joints were tested at LBNL at liquid helium temperatures over a range of magnetic fields. The joint resistance was compared with the theoretical calculations. Measurements of splice strength were also made at 300 K and 77 K.

Power conditioner for a coil-gun

International Nuclear Information System (INIS)

Zabar, Z.; Joshi, P.N.

1987-01-01

This paper describes a power conditioning scheme for introducing currents sequentially into a linear array of coils which form the barrel of a coil-gun. The projectile, a conducting cylindrical sleeve, is driven by the force exerted on it by a traveling magnetic wave-packet created by the barrel currents. Since the rate of energy transfer is proportional to the projectile velocity, it was convenient to divide the barrel into three separate sections. These correspond to the low, medium and high velocity parts of the projectile motion. Each section is excited by a different method, chosen to satisfy the need for most efficient usage of energy stored in the power supply capacitors. Experiments are described with a breadboard model that test the feasibility of the medium-velocity power conditioning scheme

Manufacture of the Poloidal Field Conductor Insert Coil (PFCI)

International Nuclear Information System (INIS)

Baker, W.; Rajainmaeki, H.; Salpietro, E.; Keefe, C.

2006-01-01

Within the framework of the R(and)D programme for ITER (International Thermonuclear Experimental Reactor) the European team EFDA (European Fusion Development Agreement) have been charged with the design and manufacture of the Poloidal Field Conductor Insert Coil (PFCI). The purpose of the PFCI is to test and demonstrate the performance of long length full scale NbTi conductors in ITER relevant conditions. The PFCI will be tested in the Central Solenoid Model Coil test facility at the JAEA Naka Japan. This paper details the complete manufacturing details of the PFCI including development, forming machining, pre-assembly, impregnation, final assembly and testing. The PFCI is a single layer wound solenoid of 9 turns with a transition joggle in the centre section of the winding and an intermediate joint connection between the upper termination and the main coil winding. To give the required overall dimensions to fit in the testing facility, pre-formed and machined glass resin composite filler pieces are assembled with the winding and finally Vacuum Pressure Impregnated to create a single assembly unit. The PFCI is enclosed for assembly in a support structure which consist of an upper and lower flange that each are made up by 4 machined stainless steel castings which are electrically insulated by epoxy glass sheet material and 12 tie rods which preload the complete assembly in the vertical direction while the upper flange is equipped with 4 radial restraining jacks and the lower flange is equipped with 4 sets of studs and shear keys to withstand the net vertical and lateral electromagnetic forces. The PFCI is equipped with inductive heaters, voltage taps, temperature transducers, strain gauges and other instrumentation as diagnostics to monitor the performance. The current status of the manufacture is that the coil is in the process of final impregnation and should be completed and delivered before the summer of this year. (author)

The Short Model Coil (SMC) dipole: an R&D program towards Nb$_{3}$Sn accelerator magnets

CERN Document Server

Bajko, M; Canfer, S; Ellwood, G; Feuvrier, J; Guinchard, M; Karppinen, M; Kokkinos, C; Manil, P; Milanese, A; Oberli, L; Perez, J-C; Regis, F; de Rijk, G

2011-01-01

The Short Model Coil (SMC) assembly has been designed, as test bench for short racetrack coils wound with Nb$_{3}$Sn cable. The mechanical structure comprises an iron yoke surrounded by a 20 mm thick aluminium alloy shell, and includes four loading pads that transmit the required pre-compression from the outer shell into the two coils. The outer shell is pre-tensioned with mechanical keys that are inserted with the help of pressurized bladders and two 30 mm diameter aluminium alloy rods provide the axial loading to the coil ends. The outer shell, the axial rods, and the coils are instrumented with strain gauges, which allow precise monitoring of the loading conditions during the assembly and at cryogenic temperature during the magnet test. Two SMC assemblies have been completed and cold tested in the frame of a European collaboration between CEA (FR), CERN and STFC (UK) and with the technical support from LBNL (US). This paper describes the main features of the SMC assembly, the experience from the dummy asse...

The SMC (Short Model Coil) dipole: An R&D program for Nb$_{3}$Sn accelerator magnets

CERN Document Server

Perez, J C; Bordini, B; Canfer, S; Ellwood, G; Feuvrier, J; Guinchard, M; Karppinen, M; Kokkinos, C; Manil, P; Milanese, A; Oberli, L; Regis, F; de Rijk, G

2012-01-01

The Short Model Coil (SMC) assembly has been designed, as test bench for short racetrack coils wound with Nb$_{3}$Sn cable. The mechanical structure comprises an iron yoke surrounded by a 20 mm thick aluminium alloy shell, and includes four loading pads that transmit the required pre-compression from the outer shell into the two coils. The outer shell is pre-tensioned with mechanical keys that are inserted with the help of pressurized bladders and two 30 mm diameter aluminium alloy rods provide the axial loading to the coil ends. The outer shell, the axial rods, and the coils are instrumented with strain gauges, which allow precise monitoring of the loading conditions during the assembly and at cryogenic temperature during the magnet test. Two SMC assemblies have been completed and cold tested in the frame of a European collaboration between CEA (FR), CERN and STFC (UK) and with the technical support from LBNL (US). This paper describes the main features of the SMC assembly, the experience from the dummy ass...

Single-Coil Defibrillator Leads Yield Satisfactory Defibrillation Safety Margin in Hypertrophic Cardiomyopathy.

Science.gov (United States)

Okamura, Hideo; Friedman, Paul A; Inoue, Yuko; Noda, Takashi; Aiba, Takeshi; Yasuda, Satoshi; Ogawa, Hisao; Kamakura, Shiro; Kusano, Kengo; Espinosa, Raul E

2016-09-23

Single-coil defibrillator leads have gained favor because of their potential ease of extraction. However, a high defibrillation threshold remains a concern in patients with hypertrophic cardiomyopathy (HCM), and in many cases, dual-coil leads have been used for this patient group. There is little data on using single-coil leads for HCM patients. We evaluated 20 patients with HCM who received an implantable cardioverter-defibrillator (ICD) on the left side in combination with a dual-coil lead. Two sets of defibrillation tests were performed in each patient, one with the superior vena cava (SVC) coil "on" and one with the SVC coil "off". ICDs were programmed to deliver 25 joules (J) for the first attempt followed by maximum energy (35 J or 40 J). Shock impedance and shock pulse width at 25 J in each setting as well as the results of the shock were analyzed. All 25-J shocks in both settings successfully terminated ventricular fibrillation. However, shock impedance and pulse width increased substantially with the SVC coil programmed "off" compared with "on" (66.4±6.1 ohm and 14.0±1.3 ms "off" vs. 41.9±5.0 ohm and 9.3±0.8 ms "on", Psatisfactory safety margin for 35-J devices. Single-coil leads appear appropriate for left-sided implantation in this patient group. (Circ J 2016; 80: 2199-2203).

Coil supporting device for a nuclear fusion device

International Nuclear Information System (INIS)

Kuno, Kazuo.

1976-01-01

Object: To reduce a thermal stress of a coil such as a magnetic limiter to minimize stress acting on a protective tube of the coil. Structure: A coil within a protective tube has its outer periphery surrounded and supported by a heat-resisting material such as ceramic at more than two positions suitably spaced lengthwise of a coil conductor, and heat insulating members are interposed between both sides of the coil and the protective tube so that it may be retained with respect to the width of the coil. Further, a heat-resisting resilient member is inserted in a clearance between an outer circumference and an inner circumference of the coil to allow a radial displacement of the coil. As a result, elongation of the coil due to thermal expansion may be escaped at the aforesaid two supports to reduce thermal stress of the coil and protective tube to support the coil within the protective tube in positively heat-resisting and insulating manner. (Kamimura, M.)

Superconducting coil protection

International Nuclear Information System (INIS)

Woods, E.L.

1975-01-01

The protection system is based on a two-phase construction program. Phase I is the development of a reliable hardwired relay control system with a digital loop utilizing firmware and a microprocessor controller. Phase II is an expansion of the digital loop to include many heretofore unmonitored coil variables. These new monitored variables will be utilized to establish early quench detection and to formulate confirmation techniques of the quench detection mechanism. Established quench detection methods are discussed and a new approach to quench detection is presented. The new circuit is insensitive to external pulsed magnetic fields and the associated induced voltages. Reliability aspects of the coil protection system are discussed with respect to shutdowns of superconducting coil systems. Redundance and digital system methods are presented as related topics

Gradient coil system for nuclear magnetic resonance apparatus

International Nuclear Information System (INIS)

Frese, G.; Siebold, H.

1984-01-01

A gradient coil system for an image-generating, nuclear magnetic resonance tomographic apparatus, particularly a zeugmatographic apparatus. The gradient coil system is arranged on a support body of rotational symmetry, illustratively a hollow cylindrical support body, having an axis which extends along the z-direction of an x, y, z coordinate system which has an origin in the center of imaging region. The gradient coil system contains two pairs of toroidal individual coils which are arranged symmetrically with respect to an x-y plane which extends through the center of the imaging region and which are arranged perpendicular to the z-axis. The direction of current flow in the individual coils of a coil pair is opposite to the direction of flow in the individual coils of the other coil pair. Moreover, further sets of coils are provided for generating field gradient Gx in the x-direction, and Gy in the y-direction. The hollow cylindrical shape of the support body on which the individual coils are arranged permit an imaging region having a substantially spherical volume with a substantially constant field gradient Gz to be achieved. Each of the coils has a predetermined linkage factor which corresponds to the product of the current flowing through the number of coil turns of the coil. Those coils which are arranged further from the plane of symmetry have a substantially larger linkage factor than the coils which are nearer to the plane of symmetry

Static Measurements on HTS Coils of Fully Superconducting AC Electric Machines for Aircraft Electric Propulsion System

Science.gov (United States)

Choi, Benjamin B.; Hunker, Keith R.; Hartwig, Jason; Brown, Gerald V.

2017-01-01

The NASA Glenn Research Center (GRC) has been developing the high efficiency and high-power density superconducting (SC) electric machines in full support of electrified aircraft propulsion (EAP) systems for a future electric aircraft. A SC coil test rig has been designed and built to perform static and AC measurements on BSCCO, (RE)BCO, and YBCO high temperature superconducting (HTS) wire and coils at liquid nitrogen (LN2) temperature. In this paper, DC measurements on five SC coil configurations of various geometry in zero external magnetic field are measured to develop good measurement technique and to determine the critical current (Ic) and the sharpness (n value) of the super-to-normal transition. Also, standard procedures for coil design, fabrication, coil mounting, micro-volt measurement, cryogenic testing, current control, and data acquisition technique were established. Experimentally measured critical currents are compared with theoretical predicted values based on an electric-field criterion (Ec). Data here are essential to quantify the SC electric machine operation limits where the SC begins to exhibit non-zero resistance. All test data will be utilized to assess the feasibility of using HTS coils for the fully superconducting AC electric machine development for an aircraft electric propulsion system.

Sub-20 nm Stable Micelles Based on a Mixture of Coiled-Coils: A Platform for Controlled Ligand Presentation.

Science.gov (United States)

Ang, JooChuan; Ma, Dan; Jung, Benson T; Keten, Sinan; Xu, Ting

2017-11-13

Ligand-functionalized, multivalent nanoparticles have been extensively studied for biomedical applications from imaging agents to drug delivery vehicles. However, the ligand cluster size is usually heterogeneous and the local valency is ill-defined. Here, we present a mixed micelle platform hierarchically self-assembled from a mixture of two amphiphilic 3-helix and 4-helix peptide-polyethylene glycol (PEG)-lipid hybrid conjugates. We demonstrate that the local multivalent ligand cluster size on the micelle surface can be controlled based on the coiled-coil oligomeric state. The oligomeric states of mixed peptide bundles were found to be in their individual native states. Similarly, mixed micelles indicate the orthogonal self-association of coiled-coil amphiphiles. Using differential scanning calorimetry, fluorescence recovery spectroscopy, and coarse-grained molecular dynamics simulation, we studied the distribution of coiled-coil bundles within the mixed micelles and observed migration of coiled-coils into nanodomains within the sub-20 nm mixed micelle. This report provides important insights into the assembly and formation of nanophase-separated micelles with precise control over the local multivalent state of ligands on the micelle surface.

Discussion of discrete D shape toroidal coil

International Nuclear Information System (INIS)

Kaiho, Katsuyuki; Ohara, Takeshi; Agatsuma, Ko; Onishi, Toshitada

1988-01-01

A novel design for a toroidal coil, called the D shape coil, was reported by J. File. The coil conductors are in pure tension and then subject to no bending moment. This leads to a smaller number of emf supports in a simpler configuration than that with the conventional toroidal coil of circular cross-section. The contours of the D shape are given as solutions of a differential equation. This equation includes the function of the magnetic field distribution in the conductor region which is inversely proportional to the winding radius. It is therefore important to use the exact magnetic field distribution. However the magnetic field distribution becomes complicated when the D shape toroidal coil is comprised of discrete coils and also depends on the D shape configuration. A theory and a computer program for designing the practical pure-tension toroidal coil are developed. Using this computer code, D shape conductors are calculated for various numbers of discrete coils and the results are compared. Electromagnetic forces in the coils are also calculated. It is shown that the hoop stress in the conductors depends only on the total ampere-turns of the coil when the contours of the D shape are similar. (author)

Fatigue assessment of the ITER TF coil case based on JJ1 fatigue tests

International Nuclear Information System (INIS)

Hamada, K.; Nakajima, H.; Takano, K.; Kudo, Y.; Tsutsumi, F.; Okuno, K.; Jong, C.

2005-01-01

The material of the TF coil case in the ITER requires to withstand cyclic electromagnetic forces applied up to 3 x 10 4 cycles at 4.2 K. A cryogenic stainless steel, JJ1, is used in high stress region of TF coil case. The fatigue characteristics (S-N curve) of JJ1 base metal and welded joint at 4.2 K has been measured. The fatigue strength of base metal and welded joint at 3 x 10 4 cycles are measured as 1032 and 848 MPa, respectively. The design S-N curve is derived from the measured data taking account of the safety factor of 20 for cycle-to-failure and 2 for fatigue strength, and it indicates that an equivalent alternating stress of the case should be kept less than 516 MPa for the base metal and 424 MPa for the welded joint at 3 x 10 4 cycles. It is demonstrated that the TF coil case has enough margins for the cyclic operation. It is also shown the welded joint should be located in low cyclic stress region because a residual stress affects the fatigue life

Construction and assembling of the trim coils for the Milan superconducting cyclotron

International Nuclear Information System (INIS)

Baccaglioni, G.; Cartegni, G.C.; Fusetti, M.; Gini, L.; Grilli, L.

1986-01-01

This paper presents the main characteristics of the trim coils realized for the heavy ions superconducting cyclotron under construction at the Milan University. The guidelines in the choice of the conductor size, of the insulation and cooling parameters are discussed in some details. The main operations in the coils construction, as winding, impregnation, electrical tests and assembling, are described

Impact of magnetic field strength and receiver coil in ocular MRI: a phantom and patient study.

Science.gov (United States)

Erb-Eigner, K; Warmuth, C; Taupitz, M; Willerding, G; Bertelmann, E; Asbach, P

2013-09-01

Generally, high-resolution MRI of the eye is performed with small loop surface coils. The purpose of this phantom and patient study was to investigate the influence of magnetic field strength and receiver coils on image quality in ocular MRI. The eyeball and the complex geometry of the facial bone were simulated by a skull phantom with swine eyes. MR images were acquired with two small loop surface coils with diameters of 4 cm and 7 cm and with a multi-channel head coil at 1.5 and 3 Tesla, respectively. Furthermore, MRI of the eye was performed prospectively in 20 patients at 1.5 Tesla (7 cm loop surface coil) and 3 Tesla (head coil). These images were analysed qualitatively and quantitatively and statistical significance was tested using the Wilcoxon-signed-rank test (a p-value of less than 0.05 was considered to indicate statistical significance). The analysis of the phantom images yielded the highest mean signal-to-noise ratio (SNR) at 3 Tesla with the use of the 4 cm loop surface coil. In the phantom experiment as well as in the patient studies the SNR was higher at 1.5 Tesla by applying the 7 cm surface coil than at 3 Tesla by applying the head coil. Concerning the delineation of anatomic structures no statistically significant differences were found. Our results show that the influence of small loop surface coils on image quality (expressed in SNR) in ocular MRI is higher than the influence of the magnetic field strength. The similar visibility of detailed anatomy leads to the conclusion that the image quality of ocular MRI at 3 Tesla remains acceptable by applying the head coil as a receiver coil. © Georg Thieme Verlag KG Stuttgart · New York.

Testing of TAMU3: a Nb₃Sn Block–Coil Dipole with Stress Management

Energy Technology Data Exchange (ETDEWEB)

McIntyre, Peter [Texas A & M Univ., College Station, TX (United States)

2015-09-20

The Accelerator Research Lab (ARL) at Texas A&M has recently concluded the construction and testing of a superconducting block-coil dipole TAMU3. TAMU3 reached 85% of the resistive-onset short sample critical current (0.1 μV/cm criterion) that was measured on extracted strands at the National High Magnetic Field Lab. Peak magnet current was 6603 amps, and all with quenches originated in the vicinity of the hard-way chicane near the exit lead of the TAMU3c inner winding. Leading up to the testing we discovered that we had made two grievous mistakes in the fabrication (we mistakenly used the wrong superconducting wire for the cables of the inner windings) and the heat treatment (we used a heat treatment that was too hot and too long). We extracted strands from the leads of the inner and outer windings, and colleagues at NHMFL performed short-sample measurements upon them. The NHMFL measurements indicated RRR ~ 2-5, which gives very little stability against microquenches. The short-sample tests of the extracted strands exhibited a long resistive transition, in which there was a current I_sc(B) beyond which it became resistive, then a higher current In(B) at which it went fully normal. Using the I_sc(B) data we predicted a short-sample limit for the revised load line of TAMU3 of 7700 A (9 T) – a disappointing reduction from the 14 T objective. On those unhappy notes we undertook the testing of the dipole. The first quench occurred at 5695 A, and the dipole trained thereafter to a maximum quench current of 6600 A (7.6 T), 85% of the compromised short-sample limit. All quenches occurred at a single location, in the region of the S-bend transition and outer lead of one inner winding. Data was collected from stress transducers on the outer windings to evaluate stress management, and on the coil ends to evaluate capture of axial forces by staticfriction lock. The low field reached prevented us from extending those tests to the stress levels where they

A neutron spin echo spectrometer with two optimal field shape coils for neutron spin precession

International Nuclear Information System (INIS)

Takeda, T.; Ebisawa, T.; Tasaki, S.; Ito, Y.; Takahashi, S.; Yoshizawa, H.

1995-01-01

We have designed and have been constructing at the C 2-2 cold neutron guide port of JRR-3M, JAERI, a neutron spin echo spectrometer (NSE) which is equipped with two optimal field shape (OFS) coils for neutron spin precession with the maximum field integral of 0.22 T m, an assembly of position sensitive detectors (PSD), a converging polarizer and a wide area analyzer. The dynamic range of scattering vector Q covers from 0.005 A -1 to 0.2 A -1 and that of energy hω from 10 neV to 30 μeV. Performance tests of the OFS coils show that the inhomogeneity of the magnetic field integral in the OFS coils with the spiral coils is so small that the NSE signal amplitude decreases little even for the neutron cross section of 30 mm diameter as the Fourier time t increases up to 25 ns, though the precession coils are close to iron covers of the neighboring neutron guide. This verifies that the OFS precession coils are appropriate for this NSE spectrometer. Another test experiment shows that the homogeneity condition of the precession magnet is loosened by use of PSD. (orig.)

Structural basis for cargo binding and autoinhibition of Bicaudal-D1 by a parallel coiled-coil with homotypic registry

International Nuclear Information System (INIS)

Terawaki, Shin-ichi; Yoshikane, Asuka; Higuchi, Yoshiki; Wakamatsu, Kaori

2015-01-01

Bicaudal-D1 (BICD1) is an α-helical coiled-coil protein mediating the attachment of specific cargo to cytoplasmic dynein. It plays an essential role in minus end-directed intracellular transport along microtubules. The third C-terminal coiled-coil region of BICD1 (BICD1 CC3) has an important role in cargo sorting, including intracellular vesicles associating with the small GTPase Rab6 and the nuclear pore complex Ran binding protein 2 (RanBP2), and inhibiting the association with cytoplasmic dynein by binding to the first N-terminal coiled-coil region (CC1). The crystal structure of BICD1 CC3 revealed a parallel homodimeric coiled-coil with asymmetry and complementary knobs-into-holes interactions, differing from Drosophila BicD CC3. Furthermore, our binding study indicated that BICD1 CC3 possesses a binding surface for two distinct cargos, Rab6 and RanBP2, and that the CC1-binding site overlaps with the Rab6-binding site. These findings suggest a molecular basis for cargo recognition and autoinhibition of BICD proteins during dynein-dependent intracellular retrograde transport. - Highlights: • BICD1 CC3 is a parallel homodimeric coiled-coil with axial asymmetry. • The coiled-coil packing of BICD1 CC3 is adapted to the equivalent heptad position. • BICD1 CC3 has distinct binding sites for two classes of cargo, Rab6 and RanBP2. • The CC1-binding site of BICD1 CC3 overlaps with the Rab6-binding site

Structural basis for cargo binding and autoinhibition of Bicaudal-D1 by a parallel coiled-coil with homotypic registry

Energy Technology Data Exchange (ETDEWEB)

Terawaki, Shin-ichi, E-mail: terawaki@gunma-u.ac.jp [Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); SPring-8 Center, RIKEN, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Yoshikane, Asuka [Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); SPring-8 Center, RIKEN, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Higuchi, Yoshiki [Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori-cho, Ako-gun, Hyogo 678-1297 (Japan); Department of Picobiology, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori-cho, Ako-gun, Hyogo 678-1297 (Japan); SPring-8 Center, RIKEN, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Wakamatsu, Kaori [Graduate School of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); SPring-8 Center, RIKEN, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)

2015-05-01

Bicaudal-D1 (BICD1) is an α-helical coiled-coil protein mediating the attachment of specific cargo to cytoplasmic dynein. It plays an essential role in minus end-directed intracellular transport along microtubules. The third C-terminal coiled-coil region of BICD1 (BICD1 CC3) has an important role in cargo sorting, including intracellular vesicles associating with the small GTPase Rab6 and the nuclear pore complex Ran binding protein 2 (RanBP2), and inhibiting the association with cytoplasmic dynein by binding to the first N-terminal coiled-coil region (CC1). The crystal structure of BICD1 CC3 revealed a parallel homodimeric coiled-coil with asymmetry and complementary knobs-into-holes interactions, differing from Drosophila BicD CC3. Furthermore, our binding study indicated that BICD1 CC3 possesses a binding surface for two distinct cargos, Rab6 and RanBP2, and that the CC1-binding site overlaps with the Rab6-binding site. These findings suggest a molecular basis for cargo recognition and autoinhibition of BICD proteins during dynein-dependent intracellular retrograde transport. - Highlights: • BICD1 CC3 is a parallel homodimeric coiled-coil with axial asymmetry. • The coiled-coil packing of BICD1 CC3 is adapted to the equivalent heptad position. • BICD1 CC3 has distinct binding sites for two classes of cargo, Rab6 and RanBP2. • The CC1-binding site of BICD1 CC3 overlaps with the Rab6-binding site.

Structured Cable for High-Current Coils of Tokamaks

Science.gov (United States)

Benson, Christopher; McIntyre, Peter; Sattarov, Akhdiyor; Mann, Thomas

2011-10-01

The 45 kA superconducting cable for the ITER central solenoid coil has yielded questionable results in two recent tests. In both cases the cable Tc increased after cycling only a fraction of the design life, indicating degradation due to fatigue and fracture among the superconducting strands. The Accelerator Research Lab at Texas A&M University is developing a design for a Nb3Sn structured cable suitable for such tokamak coils. The superconductor is configured in 6 sub-cables, and each subcable is supported within a channel of a central support structure within a high-strength armor sheath. The structured cable addresses two issues that are thought to compromise opposition at high current. The strands are supported without cross-overs (which produce stress concentration); and armor sheath and core structure bypass stress through the coil and among subcables so that the stress within each subcable is only what is produced directly upon it. Details of the design and plans for development will be presented.

An analysis of 3D solvation structure in biomolecules: application to coiled coil serine and bacteriorhodopsin.

Science.gov (United States)

Hirano, Kenji; Yokogawa, Daisuke; Sato, Hirofumi; Sakaki, Shigeyoshi

2010-06-17

Three-dimensional (3D) solvation structure around coiled coil serine (Coil-Ser) and inner 3D hydration structure in bacteriorhodopsin (bR) were studied using a recently developed method named multicenter molecular Ornstein-Zernike equation (MC-MOZ) theory. In addition, a procedure for analyzing the 3D solvent distribution was proposed. The method enables us to calculate the coordination number of solvent water as well as the strength of hydrogen bonding between the water molecule and the protein. The results for Coil-Ser and bR showed very good agreement with the experimental observations.

Coil supporting device for thermonuclear device

International Nuclear Information System (INIS)

Okubo, Minoru; Ando, Toshiro; Ota, Mitsuru; Ishimura, Masabumi.

1979-01-01

Purpose: To lower the bending stress exerted on coils thereby preventing the coils from deformation by branching the outer circumferential support frames of coil support frames disposed at an equal pitch circumferentially to the coils into plurality, and integrally forming them to the inner circumferential support frames. Constitution: Each of the support frames for supporting poloidal coils winding around a vacuum vessel is bisected at the radial midway so that the outer circumferential branches are disposed at an equal pitch and they are formed integrally with the inner circumferential support frames. The inner circumferential support frames are fixed by support posts on a bed and the outer circumferential support frames are mounted to the outer edge of wedge-like support posts. Accordingly, if the coils expand outwardly upon increase in the temperature, the stress exerted on the support frame can be decreased. (Yoshino, Y.)

Design of an 18 Tesla, tandem mirror, fusion reactor, hybrid choke coil

International Nuclear Information System (INIS)

Parmer, J.F.; Agarwal, K.; Gurol, H.; Mancuso, A.; Michels, P.H.; Peck, S.D.; Burgeson, J.; Dalder, E.N.

1987-01-01

A hybrid, part normal part superconducting 18-Tesla solenoid choke coil is designed for a tandem mirror fusion reactor. The present state of the art is represented by the 12-Tesla, superconducting NbSn coil. Future applications other than tandem mirror fusion devices needing high field solenoids might require hybrid magnets of the type described herein. The hybrid design was generated because of critical field performance limitations on present, practical superconducting wires. A hybrid design might be required (due to structural limits) even if the critical field were higher. Also, hybrids could be a cost-effective way of getting very high fields for certain applications. The 18-Tesla solenoid described is composed of an inner coil made of water-cooled, high-strength zirconium copper which generates 3 Tesla. A superconducting NbSn background coil contributes the remaining 15 Tesla. The focus of the design study was on the inner coil. Demonstration fabrication and testing was performed

Impact of coil price knowledge by the operator on the cost of aneurysm coiling. A single center study.

Science.gov (United States)

Finitsis, Stephanos; Fahed, Robert; Gaulin, Ian; Roy, Daniel; Weill, Alain

2017-09-15

Endovascular treatment of aneurysms with coils is among the most frequent treatments in interventional neuroradiology, and represents an important expense. Each manufacturer has created several types of coils, with prices varying among brands and coil types. The objective of this study was to assess the impact of cost awareness of the exact price of each coil by the operating physician on the total cost of aneurysm coiling. This was a comparative study conducted over 1 year in a single tertiary care center. The reference cohort and the experimental cohort consisted of all aneurysm embolization procedures performed during the first 6 months and the last 6 months, respectively. During the second period, physicians were given an information sheet with the prices of all available coils and were requested to look at the sheet during each procedure with the instruction to try to reduce the total cost of the coils used. Expenses related to the coiling procedures during each period were compared. 77 aneurysms (39 ruptured) in the reference cohort and 73 aneurysms (36 ruptured) in the experimental cohort were treated, respectively. There was no statistically significant difference regarding aneurysm location and mean size. The overall cost of the coiling procedures, the mean number of coils used per procedure, and the median cost of each procedure did not differ significantly between the two cohorts. Awareness of the precise price of coils by operators without any additional measure did not have a scientifically proven impact on the cost of aneurysm embolization. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Magnetic field coil in nuclear fusion device

International Nuclear Information System (INIS)

Yamaguchi, Mitsugi; Takano, Hirohisa.

1975-01-01

Object: To provide an electrical-insulatively stabilized magnetic field coil in nuclear fusion device, restraining an increase in voltage when plasma current is rapidly changed. Structure: A magnetic field coil comprises coils arranged coaxial with respective vacuum vessels, said coils being wound in positive and reverse polarities so as to form a vertical magnetic field within the plasma. The coils of the positive polarity are arranged along the vacuum vessel inside of an axis vertical in section of the annular plasma and are arranged symmetrically up and down of a horizontal axis. On the other hand, the coils of the reverse polarity are arranged along the vacuum vessel outside of a vertical axis and arranged symmetrically up and down of the horizontal axis. These positive and reverse polarity coils are alternately connected in series, and lead portions of the coils are connected to a power source by means of connecting wires. In this case, lead positions of the coils are arranged in one direction, and the connecting wires are disposed in closely contact relation to offset magnetic fields formed by the connecting wires each other. (Kawakami, Y.)

Coil supporting device in nuclear fusion apparatus

International Nuclear Information System (INIS)

Hoshi, Ryo; Imura, Yasuya.

1974-01-01

Object: To secure intermediate fittings with a coil fixed thereon by an insulating tape to a fixed body by means of fittings, thereby supporting the coil in a narrow space. Structure: A coil is secured to intermediate fittings by means of an insulating tape, after which the intermediate fittings is mounted on a fixed body through fittings to support the coil in a narrow clearance portion between a plasma sealed vessel and a main coil. (Kamimura, M.)

Superconducting Coil of Po Dipole

CERN Multimedia

1983-01-01

The Po superconducting dipole was built as a prototype beam transport magnet for the SPS extracted proton beam P0. Its main features were: coil aperture 72 mm, length 5 m, room-temperature yoke, NbTi cable conductor impregnated with solder, nominal field 4.2 T at 4.7 K (87% of critical field). It reached its nominal field without any quench.After this successful test up to its nominal field of 4.2 T, the power was not raised to reach a quench. The magnet was not installed in a beam and had no other further use. Nevertheless its construction provided knowledges and experience which became useful in the design and construction of the LHC magnets. The photo shows a detail of the inner layer winding before superposing the outer layer to form the complete coil of a pole. Worth noticing is the interleaved glass-epoxy sheet (white) with grooved channels for the flow of cooling helium. See also 8211532X.

Analysis and experimental study of wireless power transfer with HTS coil and copper coil as the intermediate resonators system

Science.gov (United States)

Wang, Xiufang; Nie, Xinyi; Liang, Yilang; Lu, Falong; Yan, Zhongming; Wang, Yu

2017-01-01

Intermediate resonator (repeater) between transmitter and receiver can significantly increase the distance of wireless power transfer (WPT) and the efficiency of wireless power transfer. The wireless power transfer via strongly coupled magnetic resonances with an high temperature superconducting (HTS) coil and copper coil as intermediate resonators was presented in this paper. The electromagnetic experiment system under different conditions with different repeating coils were simulated by finite element software. The spatial distribution patterns of magnetic induction intensity at different distances were plotted. In this paper, we examined transfer characteristics with HTS repeating coil and copper repeating coil at 77 K and 300 K, respectively. Simulation and experimental results show that HTS and copper repeating coil can effectively enhance the space magnetic induction intensity, which has significant effect on improving the transmission efficiency and lengthening transmission distance. We found that the efficiency and the distance of wireless power transfer system with an HTS coil as repeater is much higher by using of copper coil as repeater.

The Permanent Magnet Operating Mechanism of Double Coil Parallel Driven at a High Speed

Directory of Open Access Journals (Sweden)

WEI Xau-Lao

2017-02-01

Full Text Available Abstract:Operating mechanism is the main part of breaker，and the quality of breaker will directly influence the safe operation of power system. Because of the continuous improvement requirements of switch，in order to mak this actuator faster and more powerful closing，this paper proposes a double coil parallel driven permanent magnet actuator at a high speed. This paper expounds the working principle of single and double coil parallel driven permanent magnet actuator. It uses Ansoft building model and contrasts test results. In prance we designed and produced the single and double coil parallel driven permanent magnet actuator for experimental study. The simulation and experiment results show that double coil parallel driven permanent magnet actuator，compared with single coil parallel driven permanent magnet actuator，has a better and faster action performance. Thus，the double coil parallel driven permanent magnet actuator achieves a kind of optimization.

The SMES model coil. Fabrication

International Nuclear Information System (INIS)

Hanai, Satoshi; Nakamoto, Kazunari; Takahashi, Nobuji

1998-01-01

A SMES model coil was fabricated as R and D item in the development of component technologies for a 480 MJ/20 MW SMES pilot plant. The coil consists of four double-pancake windings. The coil is the same diameter but half the number of pancakes that will be needed for a SMES pilot plant. The NbTi cable-in-conduit conductor and superconducting joints between the double pancakes are cooled by a forced flow of supercritical helium. Prior to fabrication, various characteristics of the cable-in-conduit were measured by full-sized short samples from actual conductors and by scaled short samples from scaled conductors. The critical current of the scaled short samples was in agreement with that calculated from one strand of the conductor. The impedance between arbitrary dual-oxide coated strands in the full-size conductor was measured to be smaller than that obtained from two Cr-plated strands, which showed a good degree of stability in another coil. It was estimated that oxide-coated conductors would have high stability. Through fabrication of a model coil, it was demonstrated that a large forced-flow coil for a small-scale 100 kWh SMES device could be manufactured. (author)