The bismuth-based superconducting wires (Bi-2223) have been produced as commercial products since 2004. Bi-2223 superconducting wires have been applied to cables, motors, magnets, and current leads. In particular, current leads have been used in a large accelerator, and magnets have been used in a B-H curve tracer for permanent magnets and magnetic billet heaters for hot extrusion. Motors and cables have been developed and evaluated as real sized apparatus.

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An 816.4m long wire with end-to-end critical current (I_c) of 572A/cm, corresponding to the world record I_c×L value of 466,981Am/cm, was successfully obtained at Fujikura in the background of request for longer length and higher I_c from users. We are establishing the skill of routinely fabricating 500m long wires with uniform I_c distribution over 500A. An experimental stacked coil with 6 pancake coils was also fabricated without degradation and exhibited central field of 1.27 T at 50 K.

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We report changes in the degrees of tri-axial orientation as functions of applied magnetic field and rotation rate for Y₂Ba₄Cu₇O_y powder samples oriented in epoxy resin under modulated rotating magnetic fields (MRFs). Although the degrees of orientation were reduced for the decrease in both applied field and rotation rate, mechanisms of the reduction of the orientation degrees were found to be different. Optimization of the MRF conditions or quantification of tri-axial magnetic anisotropy in a target substance is required for the production of tri-axially oriented ceramics based on a colloidal process.

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This paper describes the mechanism of radiated emission from a PCB (printed circuit board) with a slit. The multilayer PCB has a power plane and a ground plane, and they make up a parallel resonator. It is reported that when there is a slit at the power plane, the resonant frequencies are varied and the strength of radiated emission is also altered. However, the radiated emission from the PCB with a slit has not been cleared, although it is generally thought that the amount of the radiated emission will be increased. In this paper, the radiated emission from a PCB with a slit is measured and numerically analyzed using FDTD. It has been shown that the amount of radiated emission decrease at 1^st mode when there is a slit. And its reason has been also cleared by investigating both amplitude and phase of the tangential electric field on the PCB with a slit.

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Particle trajectory calculations were conducted based on TS-4 magnetic probe data in the R-Z plane assuming axisymmetry. An acceleration mechanism for electrons trapped in a merging Spheromak during the formation of a FRC that is causally connected to the out of plane E_φ field during reconnection is found. The energy profile resembles a stair step like motion as the electron is accelerated from the reconnection E field on multiple passes confined to constant magnetic field lines.

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When contact failure occurs in a connector in a coaxial high-frequency (HF) signal transmission line, an electromagnetic field is radiated around the connector. The authors computed the strength of the magnetic field in the area around the cross section of a connector with contact failure. The results shows a relationship between the current at the contact point and the magnetic field around the transmission line. Using this relationship, we can predict the contact condition by observing the magnetic field around the transmission line.

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Plasma is a useful tool to synthesize carbon nano-materials including diamond, fullerene, nanotube and graphene. This review introduces the overview of these carbon nano-materials produced by thermal or non-thermal plasmas and also the authors' work related to plasma-enhanced chemical vapor deposition of carbon nanotubes and its correlation with numerical simulation of CH₄/H₂ feedstock gas plasmas. The amount of carbon atoms in the CNTs grown and that calculated from simulation showed good agreement.

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In this research, concentrations of hydrogen peroxide and dissolved ozone generated by direct current plasma within oxygen bubbles in water were measured. The current magnitude and water conductivity were changed from 1 to 7mA, and from 1 to 100 μS/cm, respectively. The highest efficiency of hydrogen peroxide generation was 0.64g/kWh at 7mA with 100μS/cm solution. The concentration of dissolved ozone decreased with increasing the discharge current, and was almost zero when the current was higher than 5mA. Non-dimensional simulation revealed that the water vapor concentration in bubbles strongly affects the generation of active species. With a large current, the amount of water vaporized into the bubbles enlarged due to a large heat flux from plasma.

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This paper discusses the effect of plastic deformation at core manufacturing on the characteristics of cores where non-oriented electrical steel sheets are used as core material. Exciting field and iron loss increase proportionally to plastic deformation in the case of r_P<10, where r_P is a ratio of plastic deformation to that at yield point. In this region, anomalous eddy currents increase because plastic deformations of crystalline grains are distributed and then the flux distribution is induced. In the case of r_P>20, the deterioration tend to saturate, and the increases in magnetic field and iron loss are 1000 to 1500A/m and 2 to 4W/kg. They are related to grain size, and high grade with larger grain may have lager field increase and smaller iron loss increase. Anomalous eddy current losses scarcely increase in this region. In actual motors, the plastic deformation affects iron loss increase although exciting current increases a little.

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The accurate magnetic properties of electrical steel sheets are important to develop high-efficiency electromagnetic devices. Especially, the H-coil method is a useful measurement technique of accurate magnetic field strength in single sheet tester. Therefore, we developed the tester of magnetic properties using the H-coil method, we called it the Stress load type - Single Sheet Tester (S-SST), and a problem was found in the iron loss measurement at high flux density, 1.6T or more. In this paper, it is shown that the cause of this problem is phase difference between induced voltage in H-coil and B-coil. In order that the phase difference make BH loop slightly twisted near the tip point, the iron losses are evaluated low. So, we propose the method of determining of phase correction values, these are measured in the absence of a specimen in the S-SST measurement system, and the phase correction method for induced voltage in a coil. Finally, the ideal results of correction on iron loss of non-oriented electrical steel sheets are shown. The proposed method is effective in calibration of a single sheet tester using the H-coil method.

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The Polyvinyl chloride (PVC), the most popular insulating material, is used as an insulating material of various electric products. When using an electrical wiring assembly code over the power capacity, PVC could melt by the joule heating and cause an electrical breakdown. Therefore, it is necessary to clarify the electrical breakdown phenomena near the melting point (170°C) in PVC. In this paper, space charge distribution and conduction current have been measured in PVC sheets up to the electrical breakdown in the range from room temperature to 200°C under DC electric field. The breakdown strength decreases with temperature in PVC. Small hetero-space charges are accumulated near both of the electrodes at room temperature region. At high temperature region above 100°C, it is observed that positive charges are injected from anode and move toward the cathode; the electric field is emphasized near the cathode due to the packet-like positive charge in PVC. It shows a thermal breakdown process of the electric fields due to positive charge behavior and conduction current increase with temperature near the melting point in PVC.

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In this letter, we studied an effect of contact failure of connector in electronic control units on radiated emissions. In order to investigate the effect, we measure the common-mode current which is one of the major causes of electromagnetic radiation when contact conditions in a connector change. On the basis of experimental result, we show that the level of radiated emission increases when the contact failure is occurred on a GND side of the connector.

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We have investigated the relation between optical property and crystallinity of PLLA. The crystalline polymer such as PLLA has inhomogeneous structure consisting of crystalline and amorphous parts, showing the strong scattering. In addition, the polarization property is a mixture of birefringence from orientation and optical rotation by chiral molecules. In this paper, we show how to determine these polarization properties and demonstrated that optical properties correlate with the crystallization.

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Concentrations of acetic acid monomers and dimers are estimated on the basis of the Gibbs free energy, and the decomposition characteristics of acetic acid contained in an artificial air in an atmospheric pressure DC corona discharge are investigated. It is found that CO₂, CO, HCOOH and HCHO are produced from acetic acid, and that all carbon atoms contained in acetic acid molecules are converted into those by-products at the input energy of 40kJ.

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