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61.
Shoya Ueno Yuki Nakamura Ken-Ichi Sugioka Masaki Kubo Takao Tsukada Masahito Uchikoshi Hiroyuki Fukuyama 《International Journal of Thermophysics》2017,38(2):16
The normal spectral emissivity of molten Cu–Co alloy with different compositions was measured in the wavelength range of 780 nm to 920 nm and in the temperature range of 1430 K to 1770 K including the undercooled condition by an electromagnetic levitator superimposed with a static magnetic field. The emissivity was determined as the ratio of the radiance from a levitated molten Cu–Co droplet measured by a spectrometer to the radiance from a blackbody calculated by Planck’s law at a given temperature, where a static magnetic field of 2.5 T to 4.5 T was applied to the levitated droplet to suppress the surface oscillation and translational motion of the sample. We found little temperature dependence of the normal spectral emissivity of molten Cu–Co alloy. Concerning the composition dependence, the emissivity decreased markedly above 80 at%Cu and reached that of pure Cu, although its dependence was low between 20 at%Cu and 80 at%Cu. In addition, this composition dependence of the emissivity of molten Cu–Co alloy can be explained well by the Drude free-electron model. 相似文献
62.
Hiroyuki Kamata Shun-ichiro Ueno Naoki Sato Toshiyuki Naito 《Fuel Processing Technology》2009,90(7-8):947-951
Mercury oxidation by hydrochloric acid over the metal oxides supported by anatase type TiO2 catalysts, 1 wt.% MOx/TiO2 where M = V, Cr, Mn, Fe, Ni, Cu, and Mo, was investigated by the Hg0 oxidation and the NO reduction measurements both in the presence and absence of NH3. The catalysts were characterized by BET surface area measurement and Raman spectroscopy. The metal oxides added to the catalyst were observed to disperse well on the TiO2 surface. For all catalysts studied, the Hg0 oxidation by hydrochloric acid was confirmed to proceed. The activity of the catalysts was found to follow the trend MoO3 ~ V2O5 > Cr2O3 > Mn2O3 > Fe2O3 > CuO > NiO. The Hg0 oxidation activity of all catalysts was depressed considerably by adding NH3 to the reactant stream. This suggests that the metal oxide catalysts undergo the inhibition effect by NH3. The activity trend of the Hg0 oxidation in the presence of NH3 was different from that observed in its absence. A good correlation was found between the NO reduction and the Hg0 oxidation activities in the NH3 present condition. The catalyst having high NO reduction activity such as V2O5/TiO2 showed high Hg0 oxidation activity. The result obtained in this study suggests that the oxidation of Hg0 proceeds through the reaction mechanism, in which HCl competes for the active catalyst sites against NH3. NH3 adsorption may predominate over the adsorption of HCl in the presence of NH3. 相似文献
63.
Katsunori Takeda Tetsuo Hattori Tetsuya Izumi Hiromichi Kawano Shinichi Masuda 《Artificial Life and Robotics》2010,15(4):421-424
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is
that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring
camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity
of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed
JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the
Chow test, which is well known as a standard method for detecting structural change in time-series data. 相似文献
64.
65.
Inoue S. Fujii T. Ueno Y. Kannari F. 《IEEE journal of selected topics in quantum electronics》1995,1(3):908-915
Crystalline thin films of polytetrafluoroethylene (PTFE) were deposited by F2 laser (157 nm) ablation in 200 mTorr Ar gas atmosphere. Combining this PTFE thin-film process with CdTe microcrystallites synthesis in sizes of 3-7 nm via KrF laser (248 nm) ablation, CdTe microcrystallites-doped PTFE thin films were fabricated. The X-ray photoemission spectra show that the main architecture of PTFE and CdTe are maintained in the doped films. CdTe microcrystallites doped in PTFE matrix show an absorption edge shift toward higher energy and a third-order optical nonlinearity, which are induced by the quantum size effect 相似文献
66.
Victor Efimov Ken Obara Daigo Ueno Akira Yamaguchi Hidehiko Ishimoto 《Journal of Low Temperature Physics》2002,126(1-2):121-126
The behaviour of
4
He impurities has been investigated through positive ion mobility measurements in liquid
3
He at milliKelvin temperatures. In spite of the enormous surface area of the cell, the influence of
4
He lasted for hundreds of hours at temperatures of 20 mK. However below 10 mK, the
4
He impurities were quickly frozen out on the cell walls and we were free from the impurity problem. Nevertheless the multiple ion signal occasionally appeared even at a few mK, although it disappeared for a number of ionization pulses. 相似文献
67.
A molecular structure viewer program, MOSBY has been developed for studies that use atomic coordinates to understand the structures of protein molecules. The program is designed to be portable with a comprehensive user interface by our high-throughput graphics library. In addition, it cooperates with extension modules customized for individual research topics and analysis. For example, an electron density module loads and displays electron density maps derived in X-ray crystallographic analysis superimposed to an atomic model. A molecular dynamics module reads a trajectory file of the results of molecular dynamics calculations and animates the structure. These plug-in modules are devised to function without modification to the MOSBY program. For variations of analysis and calculations with atomic coordinates, the portability and extensibility illustrated by MOSBY play an important rule in scientific computational tools with active software development. 相似文献
68.
Kazunori Komatani Shinichi Ueno Tatsuya Kawahara Hiroshi G. Okuno 《User Modeling and User-Adapted Interaction》2005,15(1-2):169-183
We address the issue of appropriate user modeling to generate cooperative responses to users in spoken dialogue systems. Unlike
previous studies that have focused on a user’s knowledge, we propose more generalized modeling. We specifically set up three
dimensions for user models: the skill level in use of the system, the knowledge level about the target domain, and the degree of urgency. Moreover, the models are automatically derived by decision tree learning using actual dialogue data collected by the system.
We obtained reasonable accuracy in classification for all dimensions. Dialogue strategies based on user modeling were implemented
on the Kyoto City Bus Information System that was developed at our laboratory. Experimental evaluations revealed that the
cooperative responses adapted to each subject type served as good guides for novices without increasing the duration dialogue
lasted for skilled users. 相似文献
69.
S. Nakao K. Ueno T. Hanaguri K. Kitazawa T. Fujita Y. Nakayama T. Motohashi J. Shimoyama K. Kishio T. Hasegawa 《Journal of Low Temperature Physics》1999,117(3-4):341-345
We have performed scanning tunneling microscopy/spectroscopy (STM/STS) on single crystals of heavily Pb-doped Bi
2
Sr
2
CaCu
2
O
y
(Pb-Bi2212). The obtained STM images clearly demonstrated phase separation into the and phases with lamella-type and new zigzag-like microstructures. From the site-specified tunneling measurements, it was directly confirmed that the phase possesses higher T
c
. This suggests that the phase boundaries act as strong pinning sites especially at higher temperatures. 相似文献
70.
Simone Fujii Ricardo Marcelo Reche Ribeiro Maria Brígida Dos Santos Scholz Elisabete Yurie Sataque Ono Cássio Egidio C Prete Eiko Nakagawa Itano Yoshio Ueno Osamu Kawamura Elisa Yoko Hirooka 《Food Additives & Contaminants》2006,23(9):902-909
The performance of an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on a monoclonal antibody (mAb) for ochratoxin A (OTA) detection was evaluated in a comparative study with high-performance liquid chromatography (HPLC) analysis using 68 freshly harvested coffee samples from the North of Paraná State, Brazil. The anti-OTA mAb showed high specificity and low cross-reactivity with OTA analogues (OTB and OTalpha), but cross-reacted with OTC. This ic-ELISA showed a detection limit of 3.75 ngg-1 sample, when compared to 0.80 ngg-1 by HPLC, with an ic-ELISA/HPLC correlation coefficient of 0.90. As regards OTA analysis of these coffee samples, natural contamination was detected in 10 samples (14.7%) by both methods, where the ic-ELISA values (range 3.9-7.3 ngg-1) were 1.1 to 1.6-fold higher than HPLC data (2.7-4.7 ngg-1). Five samples (7.4%) were OTA positive (range 0.84-1.30 ngg-1) only by HPLC assay, probably due to the higher detection limit reached by ic-ELISA. OTA was undetectable in 53 samples (77.9%) by both methods, while all positive samples (range 0.84-7.30 ngg-1) showed OTA levels lower than 8 ngg-1 (maximum limit recommended by the European Union). The matrix interference of green coffee was minimized by dilution of sample extracts before carrying out the ELISA assay. This mAb-based ic-ELISA can be effectively applied for OTA screening in coffee, because it is simple, sensitive and sample preparation is easy. 相似文献