Pore properties of activated carbon made from pruned apple branches on air-activation were investigated by comparison with the carbon from sugi (Cryptomeria japonica D.DON) prepared in the same way and commercial activated carbon. The results showed that the activated carbon ash prepared from pruned apple branches contained a lot of calcium, and its ash yield was highest. Besides we found that the external specific surface area and mesopores with the diameter 4-20nm range were the largest. It was supposed to be caused by catalytic action of calcium.

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Crystalline structure and magnetic properties of ordered and disordered Fe_1-x-yMn_xPt_y films (100 nm thick) were studied, and the magnetic phase diagrams were investigated. In ranges of both 0 ≤ x ≤ 0.4 and 0.45 ≤ y ≤ 0.85, all of the films had A1 type (face-centered cubic) disordered structure before annealing. At room temperature, the saturation magnetization (M_s) of the disordered Fe_0.5-xMn_xPt_0.5 and　(Fe_0.5Pt_0.5)_1-xMn_x films decreased with increasing the amount of Mn addition (x) due to its decreasing of the Curie temperature (T_c). After annealing at 600°C for 1 hour, almost of all films with ranges of 0 ≤ x ≤ 0.4 and 0.45 ≤ y ≤ 0.85 had L1₀ type (face-centered tetragonal ; a = b > c ) ordered structure. Ordered (Fe_0.5Pt_0.5)_1-xMn_x films with 0 ≤ x < 0.29 excepting x = 0.23 had high M_s of 500 ≤ M_s ≤ 800 emu/cm³ . These results suggest realizing an advantaged bit patterning process using the order-disorder transition.

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A new ultrasonic imaging method by detecting the surface vibration velocity of a sample placed on the piezoelectric transducer is described. Surface vibration velocity of a sample is optically observed and their simulation is also performed to confirm the necessity of constant voltage drive in generating arbitral velocity waveforms on the surface of piezoelectric transducer. To demonstrate the possibilities of ultrasonic imaging, characters on an object was imaged by measuring the difference in surface vibration velocity between the object and the piezoelectric transducer. An experiment for an aluminum sample shows the effectiveness of our method in non-contact ultrasonic imaging in air. The experimental results suggested that the spatial resolution of the proposed system depend on the spot size of laser light of Doppler vibrometer is also described.

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Varistors have a lot of excellent characteristics, such as symmetry of electric polarity in the V-I curve, good surge absorption and excellent non-linearity. Therefore, varistors are widely used in electrical and electronic equipments for protection device from surge, noise or ESD(electro static discharge). In particular, multilayer chip varistors are now used extensively for IC using most of portable equipments such as mobile phone and tablet PC. Multilayer chip varistors are made by stacked zinc oxide varistor material and internal electrode material such as Pd. Since the equivalent circuit of the multilayer chip varistor is formed in parallel with the capacitor and two Zener diodes, it is possible to reduce the number of electronic parts. The minimum shape is massproduced to 0402 type, which contributes to the miniaturization of the circuit board of the electronic equipments. Near future development of low-capacitance type and low-voltage type and impedance matching element would be achieved, and the applications would further expand.

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