A hydrophilic amorphous carbon film was deposited with plasma enhanced chemical vapor deposition (PECVD) using diisopropylether ((i-C3H7)2O) as a source molecule. Bonding states of hydrocarbon in the deposited film are comprised of sp3-hydrocarbon components, which is the same as the isopropy group in the source molecule. On the other hand, C=O bonding is formed in the deposited film, not as similar to the source molecule, diisopropylether. These results suggest that C-O-C in the source molecule would be cleaved. This study would propose a new deposition method of a hydrophilic amorphous carbon film with ether as a source molecule.
Changes in chemical states of amorphous carbon film during ethylene (C2H4) plasma in the floating potential were investigated with multiple-internal-reflection infrared absorption spectroscopy (MIR-IRAS) and deposition rates. IRAS spectra showed the peaks due to the sp3-CHX were observed, but no peaks due to sp2-CHX were observed. The deposition rate due to ethylene plasma were nearly twice as much as that due to methane plasma, in the same way that the number of carbons in an ethylene molecule is twice as that in a methane molecule. It is suggested that the film growth due to ethylene plasma is the same manner of that due to methane plasma; the plasma-generated hydrocarbon species such as C2H3, C2H5, which are generated in ethylene plasma are adsorbed on dangling bonds which are generated by hydrogen abstraction from the deposited film surface. As a result, the deposited film is comprised of sp3-hydrocarbon components.
A simple and useful ion measuring system for AC corona discharge is developed to understand the fundamental mechanism of the charge neutralization process. The ion measuring system consists of ion trapping plate, capacitors, and a buffer circuit op-amp. The voltage of ion trapping plate is divided by the capacitors and the voltage is measured by the op-amp buffer. The frequency response of ion measuring system is evaluated using a plate electrode faced to the ion trapping plate separated by a gap. The ratio and phase shift between voltages on the plate electrode and ion trapping plate has a constant value with the frequency lower than 10 kHz. The ion generated by corona discharge is measured using a needle-to-ring electrode. The voltage on the ion trapping plate induced by the high voltage applied to the needle electrode is almost rejected by voltage on a metal rod placed near the high voltage cable. The increase of voltage on the ion trapping plate caused by ion flows into the plate is observed. The charge flows into the plate and the ring electrode for a half cycle are estimated to be approximately 0.32×10-9 C and 1.1×10-9 C, respectively.
We investigated the behavior of a laser ablation plasma during transport in a multicusp magnetic field generated using 16 neodymium magnets. The transverse ion current density profiles in the magnetic field were measured using a Faraday cup. As the result, it was shown that the uniform region of the current density profile almost corresponded to the uniform region of magnetic flux density profile. The result also indicates that a laser ion source using the multicusp magnetic field has a potential to extract an ion beam with uniform current density around the center axis in the transverse direction.
It is well known that an air discharge immunity test method, which is specified in the International Electrotechnical Commission (IEC) standard, provides unstable test reproducibility owing to many factors such as the approach speed of an electrostatic discharge (ESD) generator, the curvatures of conductors inside equipment under test (EUT), climate conditions and the like. In this paper, to achieve stable testing repeatability, we propose an “alternative air discharge test method” using an ESD generator in its contact discharge mode to EUT covered with a non-conductive enclosure. In view of various curvatures of conductors inside the EUT, we use a spherical metal and a conical metal attached on an IEC recommended current injection target in lieu of an inner conductor of the EUT. Measurements of discharge currents are conducted with an ESD generator in contact discharge mode at test voltages from 5 kV to 15 kV through a fixed gap of 1 mm taken as a space distance between the inner conductors and the insulating enclosure surface. These measured current waveforms and their frequency spectra are compared with those for the air discharges. The dependence of the current peaks on test voltages is also investigated to reveal better testing repeatability.
The arc welding has been used in various welding methods because it is inexpensive and high strength after welding. However, it is a problem that accidents such as collapse of the bridge occur because of the welding defects. The welding of low cost and high productivity is required without the welding defects. The pulsed TIG welding is inexpensive and capable of high quality welding. The electromagnetic force contributing to penetration changes because the transient response of arc temperature and iron vapor generated from anode occurs. However, the analysis of pulsed TIG welding with metal vapor has been elucidated only metal vapor concentration near anode with transient phenomenon and heat flux. Thus, the theoretical elucidation of penetration depth with control factor has not been researched. In this paper, the contribution of metal vapor mass at the periphery part of pulsed arc to the electromagnetic force in the weld pool is elucidated. As a result, the iron vapor mass at periphery part decreased with increasing the frequency. The iron vapor was stagnated at axial center within one cycle. The electromagnetic force to the penetration depth direction in weld pool increased at axial center. Therefore, the metal vapor mass at periphery part plays an important role for the electromagnetic force increment at axial center.
The magnetic rotation angle sensor has more merits such as small-sized, low cost and the low power consumption than the optical sensor. But the magnetic rotation angle sensor has the demerit to be weak to the disturbance magnetic field applied from outside the sensor, so the magnetic rotation angle sensor needs magnetic shielding structure. We proposed the magnetic shielding structure of the parallel plate type which is the simpler technique to the magnetic shielding structure of enclosing the whole sensor with the magnetic substance. We confirmed that the parallel plate type has almost the same shielding ability as the magnetic shielding structure of enclosing the whole sensor with the magnetic substance at the magnetic detecting device. We have made a prototype and evaluated angle detection error with the disturbance magnetic field. As a result, we confirmed that the error is 0.06deg when 10mT disturbance magnetic fields hang over the sensor.
The influence of the shearing process on the iron loss of non-oriented electrical steel sheets with the grain size of 10-155 µm was investigated. The ratio of iron loss deterioration showed a strong correlation with grain size of the material, and the deterioration ratio was smaller as the decrease of grain size. The smaller grain size material had a shorter droop height in the sheared edge, and the ratio of iron loss deterioration also had a good correlation with the droop height in the sheared edge. The effective plastic strain near the sheared edge calculated by elastic-plastic analysis based on FEM showed smaller values with a small material grain size.
The embouchure is one of the most important components to playing human whistle. The purpose of this study is to clarify the influence of the embouchure in the whistle on the volume in order to ascertain the validity of the description of the whistle instruction book. When the cross-sectional area and the thickness of the opening of the lip plate of the human whistling are varied each, the air inflow amount per unit time and the pitch and volume of the generated sound were measured. Based on the relationship between the amount of air inflow per unit time and the volume of sound generated, part of whistle teaching method and the whistle instruction book described based on experience was supported by physical experiments.