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In Japan, the use of concrete pavements gradually decreased since the 1960s owing to the fact that they require some days to cure. However, recent research revealed that concrete pavements are effective for the Life Cycle Cost and the heat island phenomenon. A novel method of making concrete pavements, with which the traffic can be opened after only one-day curing, has been proposed in Japan. Furthermore, authors have developed porous concrete for road pavement, which can also cure in one day. This study proposes a new design method to reduce the production cost of porous concrete. To achieve this, the high early-strength Portland cement was replaced with ordinary Portland cement and coarse aggregate of various sizes with a single-sized coarse aggregate. Various tests revealed that the concrete prepared by the proposed design method satisfies the standard values of the bending strength and the permeability coefficient for concrete pavement for early traffic opening. Therefore, it is considered that the design method proposed herein is vital in reducing the cost of porous concrete pavements.

Effect of grinding factor and scaling up were carried out by grinding using horizontal dry bead mill. For the experiments, 2 sizes of horizontal dry bead mills with different capacities, lab and manufacturing scale, were used to study scaling up and down. The grinding experiments were performed by changing each typical grinding factor for bead mills, including the agitator peripheral speed, bead packing density, bead diameter, and material feeding speed. This set of experiments was conducted for 3 kinds of materials, silica sand of natural inorganic materials, alumina of synthetic inorganic materials, and activated carbon of organic materials. As a result, common for all materials, similar rules were found between the particle size and specific energy, the amount of mechanical energy per unit amount of material. In addition, these rules were applicable for the different-size mills, indicating that the scale can be controlled by the rules and specific energy. Also, it is revealed that when using a single type of material, changing the bead diameter changes the energy efficiency, indicating that using small-diameter bead was effective for efficient grinding.

In this study, we report on phase retrieval by the maximum likelihood method with conjugate gradient method (CG-MAL) using through-focus images in Lorentz transmission electron microscopy (LTEM). The method was evaluated using 32 simulated and experimentally obtained through-focus images of magnetic bubbles; these images were collected under a defocus range from approximately -3 mm to 3 mm. Consequently, we obtained the magnetic domain structures of the magnetic bubbles in both the simulation and the LTEM experiment. Furthermore, the CG-MAL method showed better convergence behavior than other iterative phase retrieval methods. Therefore, the method can also be widely and effectively applied to the observation of magnetic domain structures other than magnetic bubbles when highly defocused through-focus images are used.

This paper present computational study on molybdenum disulfide (MoS2 ) nanotubes with square cross sections in order to elucidate the growth mechanism and properties of experimentally synthesized nanotubes. The results show that these square nanotubes have strain energies lower than the traditional cylinder ones in the small-diameter region. They also show a much smaller band gap and higher surface energies compared with the cylindrical ones. Zigzag and armchair chirality shows qualitatively different electronic structures about the localization of the edge states.

This paper describes an attempt to synthesize bismuth-doped diamond by plasma CVD. Solid bismuth was inserted into the reaction plasma of CH4 and H2. Examination by TEM showed that most of the bismuth was included as Bi nanoparticles in the carbon nanospheres, which segregated at the grain boundary of the diamond polycrystals. Diffraction peaks corresponding to the carbon allotrope Chaoite were observed at the grain boundaries. The Raman spectra showed very complex features between 100–1600 cm− 1, suggesting the existance of molecule-like species.

Composite electrodes comprising TiO2 and MnO2 particles were prepared as photoelectrochemical capacitor electrodes that enable both photoelectric conversion and energy storage. A MnO2 electrode was also prepared for characterization of MnO2 alone, and its electrochemical capacitor property was evaluated. The MnO2 electrode showed higher specific capacitance than a RuO2 electrode. Results of the photoelectrochemical measurements demonstrated that the discharge capacity of the TiO2/MnO2 composite electrode was slightly inferior to that of the TiO2 and RuO2 electrodes using. By reducing MnO2 particle size, the composite electrode exhibited increased surface roughness and enhanced capacity. We consider that the smaller MnO2 particles can efficiently store Na+ ions even at a low photo-charge voltage of TiO2.

We studied the elemental analysis, structural morphology, mechanical, and electrical properties of carbon nanoparticles synthesized from diesel. The spherical carbon particle size in the range of about 10 to 80 nm in diameter was observed in scanning electron microscope (SEM) studies that were identified by Atomic force microscopy (AFM) study as an aggregation of carbon particles of average size 2.5 nm. The surface rms of carbon nanoparticle thin film (CNTF) was measured directly by AFM and found 0.22 nm. The Derjaguin–Muller–Toporov (DMT) elastic modulus of carbon nanoparticles (CNPs) was measured by PeakForce QNM mode of AFM. The minimum and maximum elastic modulus was measured of 0.40 GPa and 43.89 GPa, respectively. The resistivity, conductivity, magneto resistance, mobility, and average Hall co-efficient were measured by “Ecopia Hall-effect measurement system” by four-point Van der Pauw approach at ambient condition. We demonstrated I–V characteristic at the Indium/CNTF thin film interface, w...

The Ca-based (calcium) solidification material is near-neutral, therefore it is an effective material for protecting a natural environment compared to cement. The authors investigated the physical properties of the material and the basic strength characteristics of the concrete using the material in the past. However, the flowability of the concrete was not sufficient and the effective parameter depending on strength was not found. Therefore, in this research, improvement of flowability of concrete using Ca-based solidification material, which is Ca concrete, was attempted by paying attention to the unit water content. Additionally, effect of water-solidification material ratio on the properties of compressive strength and deformation was investigated. The experimental condition for the improvement of the flowability of Ca concrete was the unit water content of 165kg and 170kg. On the other hand, the experimental condition for the properties of compressive strength and deformation was water-solidification material ratio of 0.4, 0.5, 0.6, and 0.7. The slump test and the air content test were performed to figure out flowability of Ca concrete under the condition and uniaxial compression test was performed to figure out the properties of compressive strength and deformation under the condition. Loading on the specimen in the compression test was continued until specimen fractured. Based on the test results, the following knowledge was provided: (1) Increasing unit water content improved flowability of Ca concrete. (2) The compressive strength of Ca concrete was decreased with increase in the water-solidification material ratio. (3) The compressive strength of Ca concrete was correlated with solidification material-water ratio, specimen density, and static modulus of elasticity.カルシウム系固化材を用いたコンクリートの流動性を改善するため、単位水量に着目して流動性の改善を試みた。またカルシウム系コンクリートの圧縮強度・変形特性に及ぼす水固化材比の影響を検討した。その結果、単位水量の増加はカルシウム系コンクリートの流動性の改善につながった。また水固化材比が大きくなるとカルシウム系コンクリートの圧縮強度は低下し、カルシウム系コンクリートの圧縮強度は固化材水比、供試体密度、静弾性係数と相関性があることが明らかになった。

The basic feasibility of constructing hexagonal binary decision diagram (BDD) quantum circuits on GaAs-based selectively grown (SG) nanowires was investigated from viewpoints of electrical connections through embedded nanowires and electrical uniformity of devices formed on nanowires. For this, - and -oriented nanowires and hexagonal network structures combining these nanowires were formed on (001) GaAs substrates by selective molecular beam epitaxy (MBE) growth. The width and vertical position of the nanowires could be controlled by growth conditions for both - and -directions. By current–voltage (I–V) measurements, good electrical connection was confirmed at the node point where vertical alignment of embedded GaAs nanowire pieces was found to be important. SG quantum wire (QWR) switches formed on the nanowires showed good gate control over a wide temperature range with clear conductance quantization at low temperatures. Good device uniformities were obtained on the test chips, providing a good prospect for future integration. BDD node devices using SG QWR switches showed clear path switching characteristics. Estimated power-delay product values were very small, confirming the feasibility of ultra low-power operation of future circuits.

In this paper, the structural behavior of R/C cylindrical panel is analyzed by experimental results. To avoid the geometric imperfection, R/C shell specimens are made by use of a stiff steel mold. From experimental results, the load carrying behavior of R/C cylindrical panel is presented under an external lateral pressure. Even if R/C shell does not posses geometric imperfections, the inaccuracy of the reinforcement position strongly affects to the ultimate strength and the failure patterns of such shells. To explain these effects, FEM nonlinear analyses are done under the same conditions as those of experiments. The behavior of R/C cylindrical shells are well simulated under the consideration of both the geometric imperfection and several inaccuracies.

In view of applications to hexagonal binary decision diagram (BDD) LSIs, a first attempt is made to form quantum BDD node switches on selectively grown (SG) embedded quantum wires (QWRs) by molecular beam epitaxy (MBE). SG branch switches controlled by a Schottky wrap gate (WPG) were successfully fabricated by MBE growth and subsequent device processing. Gate control characteristics were studied by gate-dependent Shubnikov–de-Haas measurements, and the behavior was found to be similar to that of devices fabricated on wires by etching. The switch exhibited clear conductance quantization at low temperature, and temperature dependence of the voltage slope of conductance jump was clarified. A Y-branch BDD node device using two SG branch switches was successfully fabricated, and realized clear path switching characteristics.

The gap between patterned aluminum was filled with SiO2 formed by the reaction of SiH4-O2 gas using helicon plasma and a biased substrate. The relationship between the SiO2 deposition rate and plasma source power was investigated. It was found that the SiO2 deposition rate was dependent on the rate of SiH4 supply and was independent of the plasma source power. The sputtering rate due to biasing the substrate decreased with increase of the plasma source power. It was found also that the sputtering rate at which void generation is suppressed could be controlled not only by the bias power but also by the plasma source power. Even when the plasma source power and bias power were set at a low level, a sufficient sputtering rate was obtained. The gap-filling rate (the net deposition rate) was determined by the difference between the raw deposition rate determined by SiH4 supply and the sputtering rate and could be controlled by the plasma source power.

This work deals with the synthesis, characterization, and application of carbon nanoparticles (CNP) adorned graphene oxide (GO) nanocomposite materials. Here we mainly focus on an emerging topic in modern research field presenting GO-CNP nanocomposite as a infrared (IR) radiation detector device. GO-CNP thin film devices were fabricated from liquid phase at ambient condition where no modifying treatments were necessary. It works with no cooling treatment and also for stationary objects. A sharp response of human body IR radiation was detected with time constants of 3 and 36 sec and radiation responsivity was 3 mAW−1. The current also rises for quite a long time before saturation. This work discusses state-of-the-art material developing technique based on near-infrared photon absorption and their use in field deployable instrument for real-world applications. GO-CNP-based thin solid composite films also offer its potentiality to be utilized as p-type absorber material in thin film solar cell, as well.

In this paper investigate the feasibility of design and fabrication of digital processors based on our hexagonal BDD quantum circuit approach. Circuits were fabricated on AlGaAs/GaAs etched nanowires, using EB lithography and wet chemical etching, and their characteristics were evaluated.

Impulsive ultrasonic pulses generated by polyvinylidene fluoride (PVDF) transducers driven by step-function voltages are evaluated by experiment and simulation. The estimate of the waveforms was carried out by the spectrums of the step-function voltages and the transfer functions calculated by Mason's equivalent circuit with the consideration of absorption and diffraction in the transmitting medium. The estimated waveforms were compared to the experimental waveforms. The results showed that the -6 dB pulsewidth and the relative voltage amplitude had good agreement in experiments and simulations.

The sensitivity factors of polyvinylidene fluoride (PVDF) transducers between 5 and 50 MHz were measured based on reciprocity and self-reciprocity calibration methods. The results showed that the tendencies of the sensitivity factors over this frequency range by both methods were in good agreement.

We fabricated a multi-mesa-channel (MMC) structure by forming a periodic trench just under a gate electrode to improve the uniformity of effective electric field in the channel in an AlGaN/GaN high electron mobility transistor (HEMT). A unique performance, i.e., a nearly temperature-independent saturation drain current, was observed in the MMC device in a wide temperature range. A two-dimensional (2D) potential calculation indicates that the mesa-side gate effectively modulates the potential, resulting in a field surrounding 2D electron gas. Such a surrounding-field effect and a relatively lower source access resistance may be related to a unique current behavior in the MMC HEMT.

The influence of gas desorption from fluorine-doped silicon oxide (SiOF) film prepared by high-density-plasma chemical vapor deposition (CVD) upon TiN/Ti film is investigated. In this investigation, two types of SiOF films, containing 14% and 6% fluorine atoms, are compared with regard to gas desorption and diffusion of fluorine, hydrogen and oxygen atoms into TiN/Ti film on SiOF film, as-deposited on TiN/Ti/SiOF film and after 400°C annealing. In addition, W film was prepared on TiN/Ti/SiOF film in order to examine the practical effect of gas desorption upon adhesion between Ti film and SiOF film. Thermal desorption mass spectroscopy (TDS) and secondary-ion mass spectroscopy (SIMS) spectral studies clarified the following. (1) SiOF film containing 14% fluorine atoms has a high hydrogen-fluoride content due to moisture absorption after exposure to air, while that containing 6% fluorine atoms does not. (2) During deposition of TiN/Ti film at 200°C, many fluorine and hydrogen atoms diffuse from SiOF film containing 14% fluorine atoms and are trapped within the Ti film or the Ti/SiOF interface. (3) During 400°C annealing, more fluorine atoms diffuse from SiOF film containing 14% fluorine atoms and are also trapped within the Ti film. (4) Fluorine atoms trapped within the Ti film degrade the adhesion between Ti film and SiOF film.