Nagoya Institute of Technology

About: Nagoya Institute of Technology is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Thin film & Turbulence. The organization has 10766 authors who have published 19140 publications receiving 255696 citations. The organization is also known as: Nagoya Kōgyō Daigaku & Nitech.

Post-growth annealing of zinc oxide thin films pulsed laser deposited under enhanced oxygen pressure on quartz and silicon substrates

Abstract: Zinc oxide (ZnO) thin films have been prepared by pulsed laser deposition (PLD) technique at room temperature on quartz and single crystal silicon (1 0 0) substrates. The oxygen ambient gas pressure was attained at 6 Torr during the deposition. The deposited films were post-growth annealed in air at various annealing temperatures for 30 min. The X-ray diffraction (XRD), optical and electrical properties have been measured to study the properties of the films as a function of annealing temperatures. XRD has shown the strength of (0 0 2) peak increases and FWHM value decreases as the annealing temperatures increases from 200 to 600 °C. The post-growth annealed at 600 °C show dominant c -axis oriented hexagonal wurtize crystal structure and exhibit high average transmittance about 85% in the visible region and very sharp absorption edge at 376 nm with energy band gap of approximately 3.46 eV. Electrical measurement indicates the resistivity decreases with the annealing temperatures up to 600 °C, after which it increases with higher annealing temperatures at 800 °C. The complex of oxygen vacancy in the ZnO films may be the source of low conductivity in undoped ZnO films.

Structures of pyridine carboxylate complexes of cobalt(ii) and copper(ii)

Abstract: The syntheses and crystal structures of [Co(nic)2(H2O)4] (1). [Co(iso)2(H2O)4] (2). [Cu(nic)2(H2O)4] (3), and [Cu(iso)2(H2O)4] (4) (nic = nicotinate; iso = isonicotinate) are reported. Complex 1 crystallizes in monoclinic, space group C2/m with cell parameters a =14.150(4). b = 6.883(2)., c = 8.497(2) A, β= 118.28(2)° and Z = 2. The other crystals. 2. 3. and 4. are all triclinic, PĪ; a = 9.777(3), b = 6.348(4), c = 6.888(3)A, a= 113.10(6)., β= 110.55(3). γ = 97.61(5)°, and Z=l for 2; a = 7.0281(4), b = 7.7176(6), c = 8.6978(7)A, a = 68.103(7), β = 68.526(5), γ = 62.550(6)°, and Z=1 for 3; a = 9.1807(4), b = 6.3334(3), c = 6.8871(3)A, a= 108.213(4), β = 99.433(4), γ= 105.190(4)°, and Z= 1 for 4. The arrangements around the metal ions are trans-octahedra with two pyridyl nitrogens and two aqua oxygens in the equatorial positions and two aqua oxygens in the axial positions, although the Cu(II) complexes show a larger Jahn-Teller distortion.

Clustering Analysis in Wireless Sensor Networks: The Ambit of Performance Metrics and Schemes Taxonomy

Abstract: Research on wireless sensor network (WSN) has increased tremendously throughout the years. In WSN, sensor nodes are deployed to operate autonomously in remote environments. Depending on the network...

A novel starting method of sensorless salient-pole brushless motor

Abstract: Brushless DC motors are receiving much attention for drive application because of their high efficiency, high torque to current ratio and high power density. Among various types of brushless DC motors, the salient-pole brushless motor is attractive from two standpoints: torque/current ratio; and feasibilities of sensorless drive and stable starting without a position sensor. Unlike the conventional cylindrical rotor motor, the salient-pole brushless motor produces additional reluctance torque, which improves the torque/current ratio. In addition to that, the winding inductance is a function of rotor position and a novel approach to rotor position estimation is possible without using a position sensor. The paper presents a sensorless drive of a 2.2 kW salient-pole brushless DC motor and emphasis is placed on stable starting by estimating initial rotor position before starting. To estimate initial rotor position, two types of pilot voltages from an inverter are provided. The pilot voltages are rectangular pulsewise DC voltages with different duties and the resultant current peaks are used to estimate the initial rotor position before starting. The proposed algorithm for initial rotor position identification is verified by simulations and experiments. >