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排序方式: 共有675条查询结果,搜索用时 20 毫秒
41.
Ryo Toda Yuki Matsushita Mitsunori Hieda Taku Matsushita Nobuo Wada 《Journal of Low Temperature Physics》2007,148(5-6):785-790
We have measured the heat capacity of 3He adsorbed on three-dimensionally connected nanopores, 2.7 nm in diameter, preplated with about 1.3 atomic layers of 4He. At low coverages of 3He, the 3He heat capacity is roughly constant at the measured temperatures between 0.1 and 1 K. Its molar heat capacity is on the order
of the gas constant R, between 1.1R and 1.8R. This suggests a Boltzmann gas state of the adsorbed 3He. At high coverages, the heat capacity is likely approaching linear in T at low temperatures, which suggests a degenerate state at further lower temperatures. 相似文献
42.
Zhihu Chen Kwan-Yee K. Wong Yasuyuki Matsushita Xiaolong Zhu 《International Journal of Computer Vision》2013,102(1-3):3-17
In this paper, we introduce a novel method for depth acquisition based on refraction of light. A scene is captured directly by a camera and by placing a transparent medium between the scene and the camera. A depth map of the scene is then recovered from the displacements of scene points in the images. Unlike other existing depth from refraction methods, our method does not require prior knowledge of the pose and refractive index of the transparent medium, but instead can recover them directly from the input images. By analyzing the displacements of corresponding scene points in the images, we derive closed form solutions for recovering the pose of the transparent medium and develop an iterative method for estimating the refractive index of the medium. Experimental results on both synthetic and real-world data are presented, which demonstrate the effectiveness of the proposed method. 相似文献
43.
Catalin Popa Yuki Okayasu Ken-ichi Katsumata Toshihiro Isobe Nobuhiro Matsushita Akira Nakajima Taisuke Kurata Kiyoshi Okada 《Journal of Materials Science》2013,48(2):941-947
Porous mullite ceramics with unidirectionally oriented pores were prepared by an extrusion method using rayon fibers as the pore formers. Rayon fibers of 8.1, 9.6, 16.8, and 37.6 μm in diameter were used as the pore formers and were kneaded with alumina powder, kaolin clay, China earthen clay, and water to form pastes. These pastes were extruded into cylindrical tubes, dried, and fired at 1500 °C for 4 h. The apparent porosities ranged from 45.7 to 48.2 %. The pore size distributions showed a sharp peak at 9.4, 10.0, 15.6, and 30 μm with increasing fiber diameters. The height of the capillary rise was 1780, 1670, 1320, and 950 mm with increasing fiber diameter. The maximum capillary rise is much higher than previously reported. The contact angle and effective pore radius that determine the capillary rise ability were calculated by fitting the capillary rise curves using the Fries and Dreyer’s equation. 相似文献
44.
Masahiro Kishida Ken-ichiro Ichiki Toshiaki Hanaoka Hideo Nagata Katsuhiko Wakabayashi 《Catalysis Today》1998,45(1-4):203-208
It was previously found that the silica-supported rhodium catalyst prepared using water-in-oil microemulsion had rhodium particles partly, or wholly, embedded in silica. In this work, consequently, we investigated the effect of hydrolysis conditions of tetraethylorthosilicate, employed as the source of silica, on the atomic ratio of surface rhodium in contact with the gas phase, to total surface rhodium of nanoparticles. This ratio is denoted as R in this paper. R became higher when the catalyst was prepared under the following hydrolysis conditions: a shorter hydrolysis time and a smaller amount of tetraethylorthosilicate. On the other hand, R showed the minimum value when the water content in the preparation solution was 33 vol%. From these results, it is demonstrated that it was important to form silica as early as possible in hydrolysis of TEOS in order to increase R values. In addition, the effect of R on the catalytic behavior in CO hydrogenation was investigated. At R values below 30%, the turnover frequencies increased with a decrease in R. 相似文献
45.
Helical carbon and graphite films were prepared from iodine-doped helical polyacetylene (H-PA) film using currently developing morphology-retaining carbonization. It was found from scanning electron microscopy (SEM) observations that the hierarchical helical morphology of the H-PA film remains unchanged even after the carbonization at 800 °C. Besides, the weight loss of the film due to the carbonization was very small, which was only a few percent to the weight of the film before doping. Furthermore, the graphite film prepared by the subsequent heating at 2600 °C still retained the same morphology as those in the original H-PA film and in the helical carbon film prepared at 800 °C. X-ray diffraction (XRD) and Raman scattering measurements were then pursued. The results showed that graphitic crystallization proceeds in the carbon film through the heat treatment at 2600 °C. Transmission electron microscopy (TEM) image of a single helical graphitic fibril was also observed by ultrasonicating the graphite film in ethanol. Carbonization of the H-PA films by way of iodine doping was found to afford helical carbon and graphite films, where spiral morphologies and even helical fibril structures were completely preserved. 相似文献
46.
The phase diagram of the Sb2Se3-CuInSe2 pseudobinary system is constructed by using differential thermal analysis and X-ray diffraction. Based on the constructed phase diagram, solution growth of CuInSe2 crystals is investigated. The grown crystals are evaluated by X-ray diffraction, electron probe microanalysis, Hall effect and inductively coupled plasma measurements. The results indicate that the crystals are not contaminated by the constituent of the flux, i.e., Sb. Hence, Sb2Se3 is promising as a solvent for the growth of CuInSe2 crystals at temperatures lower than 800°C. 相似文献
47.
Development of multianode photomultiplier tube 总被引:1,自引:0,他引:1
Fumuhiko Takasaki Hitoshi Saito Tohru Fukui Teruhiko Matsushita Toshihiro Suzuki 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1987,260(2-3):447-450
We have developed a multianode photomultiplier tube (MAPMT) which has a sensitive cathode diameter of 36 mm and an anode with 88 segments. The position sensitivity of the tube was studied by using light from a LED and scintillation light from a scintillation-fiber bundle. We observed particle tracks for the first time by using a single photomultiplier tube. 相似文献
48.
Yuki Matsushita Junko Taniguchi Ryo Toda Hiroki Ikegami Taku Matsushita Mitsunori Hieda Nobuo Wada 《Journal of Low Temperature Physics》2008,150(3-4):342-346
We have studied heat capacities of 4He adsorbed in straight nanopores 1.8, 2.2, and 2.8 nm in diameter. Heat capacities of the 4He fluid film on the solid layer at 0.08–0.4 K show power laws close to T in 1.8 nm pores, close to T
2 in 2.8 nm pores, and a crossover from T to T
2 with increasing temperature in 2.2 nm pores. These heat capacities are explained by a model assuming a phonon dispersion
with continuous one-dimensional (1D) states in the axial direction and discrete energy levels in the azimuthal direction.
By fitting experimental data to the model, the phonon velocity along the pore axis and the energy gap for propagation in the
cross section are derived. At temperatures sufficiently lower than the energy gap, where the thermal wave length of phonons
is much longer than the effective pore diameter, the 4He fluid films show a T-linear heat capacity of 1D phonons propagating only along the pore axis. At higher temperatures, a 1D-2D crossover of phonons
occurs.
相似文献
49.
Limitations of the method using peroxidase activity of hemoglobin for detecting lipid hydroperoxides
The method using peroxidase activity of hemoglobin (Hb) for the determination of lipid peroxides was examined by using pure
methyl linoleate hydroperoxides, trilinoleoylglycerol hydroperoxides and egg yolk phosphatidylcholine hydroperoxides as substrates
and tetramethyl benzidine as electron donor for the peroxidase reaction of Hb. The reactivities of these substrates were quite
varied. Furthermore, some electron donors were tested for peroxidase activity of Hb, but none showed a complete reduction
of methyl linoleate hydroperoxides. From these results, it seems the Hb method needs to be carefully applied to biological
materials that contain mixtures of different types of lipid classes. 相似文献
50.
Ruwan Gallage Atsushi Matsuo Takeshi Fujiwara Tomoaki Watanabe Nobuhiro Matsushita Masahiro Yoshimura 《Journal of the American Ceramic Society》2008,91(7):2083-2087
Crystalline CeO2 films and patterns have been successfully fabricated in a "single-step process" at moderate temperature. In this process, the combination of the ink-jet technique and depositing the precursor on a hot substrate (≤300°C) gave crystalline CeO2 without further heat treatment. X-ray diffraction analysis revealed that the phase formed was crystallized ceria with nanosized (<10 nm) crystallites. The film thickness was several hundred nanometers and the pattern width was about 150 μm. Scanning electron microscopy analysis showed that the films and patterns were free of cracks and adhered to the substrate. This is the first report about the direct patterning of crystalline CeO2 without postfiring or posttreatments like masking, etching, etc. 相似文献