[en] Progress in installing the Vivitron generator structure and isolators as of 30 September 1988 is indicated. The next steps in the installation are summarized

No abstract available

[en] To guide the formulation of this program, nineteen speakers generally representing the magnet community - manufacturers, designers, and materials people - met and presented a series of talks in six sessions. Sessions topics included: magnet insulator environment, current testing activities, irradiation sources, failure modes, test parameters, and insulator design. Each presentation was discussed by the meeting, at-large, and the concensus opinions of these discussions were noted. After the conclusion of the talks, the meeting was subdivided into four subcommittees to consider and make recommendations on the following topics: irradiation facilities and dosimetry, insulator compositions and specimen sizes and shapes, test procedures and equipment, and specimen loads, influence of magnet mechanical and thermal cycles on test program, and international cooperation

[en] A Novocontrol Alpha-A High Resolution Dielectric, Conductivity, Impedance and Gain-Phase Modular Measurement System is used to carry out high resolution dielectric, conductivity, impedance and gain phase modular measurements in a variety of solid samples. The instrument encountered breakdown. This report summarizes the frequent problems encountered during maintenance of the instrument and solutions to them. (author)

[en] High voltage bushing is one of the key components of Indian Test Facility. It is designed to provide 100 kV electrical isolation to all high voltage feedlines from the electrically grounded vessel. It also forms vacuum boundary between the vessel and the outer atmosphere. Conventional vacuum compatible porcelain insulator is selected for this purpose. However, to accommodate several high voltage feedlines in a single insulator, diameter of the insulator has been kept as ∼1 m. Further, steps have been provided at both the ends for porcelain-metal vacuum seal transitions which is the challenging step during the fabrication of insulator. This paper describes the design criteria, analysis, manufacturing phases, encountered issues and remedial actions taken to optimize the design, ensuring its manufacturability without compromising operational requirements. (author)

[en] The introduction of cable joints and optical repeaters into submarine telecommunication cable inevitably results in amalgamation regions in the polyethylene insulation. These amalgamation regions are known to increase the probability of high voltage breakdown, when compared with the bulk material. This increased risk has been attributed to the accumulation of space charge in the amalgamation regions. Measurement of the space charge accumulation (using the pulsed electro-acoustic technique), and calculation of the resultant electric field distributions of both press moulded LDPE and injection moulded LDPE containing an amalgamation zone were conducted. The space charge dynamics are discussed, and the roles of interfacial stress and Schottky injection on the space charge accumulation are detailed

[en] This patent describes a superconducting device comprising a first superconducting layer, a junction layer on the first superconducting layer, an insulating layer on the first superconducting layer, at least one superconducting area on the junction layer surrounded by the insulator layer, superconducting connector pad means disposed over the superconducting area, and superconducting wire means electrically connected to the superconducting connector pad means. The improvement comprising a first metal layer is disposed over the insulator layer and intermediate the superconducting area. The connector pad means and a second metal layer are disposed between the connector pad means and the superconductor wire means. The first metal layer covers the superconducting area and the first and second metal layers are sufficiently thin to allow quantum mechanical tunneling between the connector pad means and the superconducting area and the connector pad means and the superconducting wire means, respectively

[en] Topological insulators (TIs) are materials that behave as insulators in its interior and have conducting boundaries or edges. This unique characteristic of topological insulator was realized because of strong spin orbit coupling (SOC) of heavy elements. Here, we present the magnetotransport study of nano device made from mechanically exfoliated flake of PbBi₄Te₇ topological insulator single crystal. The temperature variation of R_xx, illustrated in this article, showing positive temperature coefficient of resistance above 15 K and bellow 15 K, it shows saturating nature, reflecting the bulk metallic signature. We present the observations of weak antilocalization and Shubinikov-de-Haas (SdH) oscillations accompanied by unique conductance fluctuations

[en] Nb₃Sn is the best superconductor candidate for the realization of high field magnets (>11 Tesla), its implementation remains delicate because of the great brittleness of material after the heat treatment necessary to the formation of Nb₃Sn compounds. The conventional insulation for Nb₃Sn requires to perform, after the heat treatment, a vacuum resin impregnation, which adds to the cost and raises failure risk. We have proposed an innovating ceramic insulation deposited directly on the unreacted conducting cable. After the heat treatment of the niobium tin, we obtain a coil having a mechanical cohesion, while maintaining a proper conductor positioning and a suitable electric insulation. After a rheological study, to characterize the impregnated suspension, we have shown that using this insulation in a coil manufacture process does not affect the electrical properties of the Nb₃Sn wires. A solenoid of small dimensions was tested with success in high external magnetic fields and has produced a magnetic field of 3.8 T under 740 A. (author)

[en] A radial insulation structure which is used in long pulse high current diode is introduced in this paper. The theory of vacuum flashover and the idea of design are brief introduced. Cone-shaped insulator was used. The geometry structure parameters were optimized by simulating the static electrical field distributing. Experiment was done on a pulse power source with 200 ns pulse width. The maximum voltage 750 kV was obtained, and the average stand-off electrical field of insulator is ∼50 kV/cm