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101.
Changho Jung Hideyuki Tsuboi Michihisa Koyama Momoji Kubo Ewa Broclawik Akira Miyamoto 《Catalysis Today》2006,111(3-4):322-327
CO adsorption over Pd4 and Pt4 cluster supported by c-ZrO2(1 1 1) and CeO2(1 1 1) catalyst systems was investigated using periodic density functional method in order to clarify the support effect on CO activation. We found that the support increases the CO activation for bridge and three-fold sites but decreases for the atop site. Moreover, it was found that the support changes the site preference for the CO adsorption. Bridge site on both the Pt4/c-ZrO2 and Pt4/CeO2 show larger CO adsorption energies than those on the other sites while the atop site is energetically preferable on isolated Pt4 cluster. c-ZrO2 supported Pd shows the largest CO activation with large charge transfer from the catalyst to the CO molecule. This reveals that ZrO2 supported Pd can be a good catalyst for CO activation because of its higher probability to the three-fold site CO adsorption. We also found that positively charged M4 clusters on the support keep their strong electron-donating properties and have enough charge density to contribute to the activation of an adsorbed CO molecule by a charge transfer. 相似文献
102.
Amakura Y Kondo K Akiyama H Ito H Hatano T Yoshida T Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(4):178-181
As part of an investigation on the chemical constituents and contaminants of the basidiomycete Pleurocybella porrigens (Japanese name: Sugihiratake), we analyzed the UV-detected constituents of this mushroom using HPLC. One of the major UV peaks detected was isolated and identified as a-eleostearic acid, a long-chain fatty acid with a conjugated triene moiety, based on the results of spectroscopic methods. alpha-Eleostearic acid was concluded to be a characteristic fatty acid of P. porrigens, because it was not detected in eight other edible mushrooms examined. Free long-chain fatty acids in P. porrigens and other edible mushrooms were analyzed by HPLC after derivatization with acidic 2-nitrophenylhydrazine hydrochloride. Oleic acid was the main fatty acid in P. porrigens, and saturated long-chain fatty acids such as linoleic acid, palmitic acid, and stearic acid, together with a-eleostearic acid, were also detected. 相似文献
103.
In this study, multi-objective genetic algorithms (GAs) are introduced to partial least squares (PLS) model building. This method aims to improve the performance and robustness of the PLS model by removing samples with systematic errors, including outliers, from the original data. Multi-objective GA optimizes the combination of these samples to be removed. Training and validation sets were used to reduce the undesirable effects of over-fitting on the training set by multi-objective GA. The reduction of the over-fitting leads to accurate and robust PLS models. To clearly visualize the factors of the systematic errors, an index defined with the original PLS model and a specific Pareto-optimal solution is also introduced. This method is applied to three kinds of near-infrared (NIR) spectra to build PLS models. The results demonstrate that multi-objective GA significantly improves the performance of the PLS models. They also show that the sample selection by multi-objective GA enhances the ability of the PLS models to detect samples with systematic errors. 相似文献
104.
Hideyuki HIRAZAWA Hiromichi AONO Takashi Naohara Tsunehiro MAEHARA Yuji WATANABE 《钢铁研究学报(英文版)》2012,(Z1):596-599
Mg1-XCuXFe2O4 type spinel ferrite was prepared by solid reaction method in order to discuss the heat generation ability in AC magnetic field.The cubic type ferrite structure was obtained for X=0-0.6 samples calcined at1200℃,and the mixture phase of cubic and tetragonal structures were obtained for X=0.7,0.8 samples from XRD result.The highest lattice parameter and highest hysteresis loss value were also shown at X=0.6 sample,the crystal distortion was increased with increase the Cu2+substitution in cubic type ferrite structure.The sized nano Mg0.4Cu0.6Fe2O4 powder was prepared by physical milling method using beads milling.The highest heat generation in the AC magnetic field was obtained for the 6 h milled samples using 0.1mm beads.The Cu2+substitution for MgFe2O4 ferrite and the beads milling were very effective for the improvement of their heat generation ability in AC magnetic field. 相似文献
105.
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107.
Takashi Minemoto Mikio Murozono Yukio Yamaguchi Hideyuki Takakura Yoshihiro Hamakawa 《Solar Energy Materials & Solar Cells》2006,90(18-19):3009-3013
Structural and economical merits of a spherical silicon solar cell with semi-concentration reflector system have been discussed. The roles of the reflector system have been clarified; the reflector improves short-circuit current density and also open-circuit voltage by 4–6 times concentration to make a light irradiation area comparable to a p–n junction area. We have theoretically demonstrated that the spherical Si solar cell with semi-concentration reflector system can realize a performance comparable to that of conventional Si solar cells, with less amount of silicon material use. 相似文献
108.
Elevation of bovine serum C-reactive protein and serum amyloid P component levels by lactation 总被引:1,自引:0,他引:1
M Morimatsu A Watanabe K Yoshimatsu T Fujinaga M Okubo M Naiki 《The Journal of dairy research》1991,58(3):257-261
C-reactive protein (CRP) and serum amyloid P component (SAP), which are known to increase in sera from humans and many other animals with acute inflammation caused by infection, toxic drug administration or injury, were previously purified from bovine serum. These serum levels were determined by enzyme-linked immunosorbent assay (ELISA) using specific antiserum to bovine CRP or SAP which was prepared by immunizing rabbits and goats with each purified protein. Among 68 healthy Holstein cows, 45 non-lactating cows had levels of CRP and SAP of 20.6 +/- 1.4 and 27.6 +/- 1.3 micrograms/ml respectively; 23 lactating cows had higher levels of CRP and SAP (76.0 +/- 13.6 and 38.3 +/- 5.5 micrograms/ml respectively). In the latter group, there was a high correlation between milk yield and serum CRP levels (P less than 0.001). From these observations, it was assumed that lactation might stimulate CRP synthesis rather than SAP synthesis in bovine liver as an acute phase reaction, and that CRP might be called a lactation-associated protein. 相似文献
109.
Md. Abdul Mannan Hideyuki Noguchi Masamitsu Nagano Yuji Baba 《Thin solid films》2010,518(15):4163-1014
Hexagonal boron carbonitride (h-BCN) hybrid films have been synthesized on highly oriented pyrolytic graphite by radiofrequency plasma enhanced chemical vapor deposition using tris-(dimethylamino)borane as a single-source molecular precursor. The films were characterized by X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) and Raman spectroscopic measurements. XPS measurement showed that the B atoms were bonded to C and N atoms to form the sp2-B-C-N atomic hybrid chemical environment. The atomic composition estimated from the XPS of the typical sample was found to be almost B1C1N1. NEXAFS spectra of the B K-edge and the N K-edge had the peaks due to the π* and σ* resonances of sp2 hybrid orbitals implying the existence of the sp2 hybrid configurations of h-BCN around the B atoms. The G band at 1592 and D band at 1352 cm− 1 in the Raman spectra also suggested the presence of the graphite-like sp2-B-C-N atomic hybrid bonds. The films consisted of micrometer scale crystalline structure of around 10 µm thick has been confirmed by the field emission scanning electron microscopy. 相似文献
110.
Shiro Shimada Motoki Yoshimatsu Hideaki Nagai Masaaki Suzuki Hisashi Komaki 《Thin solid films》2000,370(1-2):137-145
Single phase TiN and AlN films were prepared on a Si wafer from titanium tetra-etoxide and aluminum tri-butoxide solutions dissolved in ethanol and toluene, respectively, using an Ar/N2/H2 radio-frequency (r.f.) inductive thermal plasma chemical vapor deposition (CVD) method. The films were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, measurement of electrical resistivity and Vickers microhardness. Factors affecting the formation of the films (lattice parameter, chemical composition, oxygen/carbon content, and deposition rate of the films) were examined in terms of the N2 flow rate (2.5–4.5 slm), substrate temperature (300–700°C), feed rate of the solution (0.025–0.3 ml/min), and the mole ratio of the alkoxide solution (1:1–1:3). The optimum conditions for preparation of TiN films produced a film 0.2–3 μm thick with an oxygen content of 8 at.% and a free carbon content of 4 at.%, showing an electrical resistivity of 370 μΩ cm. The optimum conditions for AlN films produced a film 0.3 μm thick containing 14 at.% oxygen and 8 wt.% carbon. The deposition rate of the TiN film was determined to be 30–35 nm/min. The Vickers microhardness of the TiN and AlN films was found to be 10±1 and 13±3 GPa, respectively. 相似文献