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41.
W. H. Cassinelli L. S. F. Feio J. C. S. Araújo C. E. Hori F. B. Noronha C. M. P. Marques J. M. C. Bueno 《Catalysis Letters》2008,120(1-2):86-94
The effect of the addition of CeO2 or La2O3 on the surface properties and catalytic behaviors of Al2O3-supported Pd catalysts was studied in the steam reforming of methane. The FTIR spectroscopy of adsorbed CO and the Pd dispersion
suggest the partial coverage of Pd0 by ceria or lanthana species. This could lead to the formation of an adduct MPd
x
O (M = Ce or La) at the surface of the metal crystallites. The addition of ceria or lanthana resulted in an increase of the
turnover rate and specific rate for steam reforming of methane. One possible explanation if that the Pd0*Pdδ+O–M interfacial species (M = Ce or La) are oxidized by H2O or CO2, promoting the O* transfer to the metal surface. This could facilitate the removal of C* species from the metal surface,
resulting in the increase of specific reaction rate and increase of the accessibility of CH4 to metal active sites. 相似文献
42.
1 Introduction MEMS (MicroElectroMechanicalSystem )basedonsemiconductormicrofabricationplaysim portantrolesforexampleinthe peripheryofITsystems.NEMS (NanoElectroMechanicalSys tem)containsnano_scalestructures.Sophisticatedandhighperformancesystemsbasedonth… 相似文献
43.
Hiromichi Gima Jun Adachi Masahito Katayama Hiroaki Muta Masayoshi Uno Shinsuke Yamanaka 《Journal of Nuclear Materials》2009,389(1):155-159
We prepared polycrystalline pellets of (U,Y)O2, containing YO1.5 up to 11 mol.%. We performed indentation tests on the pellets, and evaluated the Young’s modulus and hardness. We measured the heat capacity and the thermal diffusivity, and evaluated the thermal conductivity. We succeeded in evaluating the effect of Y content on the thermophysical properties of (U,Y)O2. We revealed that the Young’s modulus, hardness, and thermal conductivity of (U,Y)O2 decreased with increasing the Y content. 相似文献
44.
45.
Tetsuro Hori Naoki Fukuoka Tetsuya Masuda Yasuo Miyake Hiroyuki Yoshida Akihiko Fujii Yo Shimizu Masanori Ozaki 《Solar Energy Materials & Solar Cells》2011,95(11):3087-3092
Bulk heterojunction solar cells utilizing soluble phthalocyanine derivative, 1,4,8,11,15,18,22,25-octahexylphthalocyanine (C6PcH2) have been investigated. The active layer was fabricated by spin-coating the mixed solution of C6PcH2 and 1-(3-methoxy-carbonyl)-propyl-1-1-phenyl-(6,6)C61 (PCBM). The photovoltaic properties of the solar cell with bulk heterojunction of C6PcH2 and PCBM demonstrated the strong dependence of active layer thickness, and the optimized active layer thickness was clarified to be 120 nm. By inserting MoO3 hole transport buffer layer between the positive electrode and active layer, the FF and energy conversion efficiency were improved to be 0.50 and 3.2%, respectively. The tandem organic thin-film solar cell has also been studied by utilizing active layer materials of C6PcH2 and poly(3-hexylthiophene) and the interlayer of LiF/Al/MoO3 structure, and a high Voc of 1.27 V has been achieved. 相似文献
46.
Shigekazu Yano Yukari Hori Tatsuro Kijima Hiroyuki Konno Wasana Suyotha Kazuyoshi Takagi Mamoru Wakayama 《Journal of Applied Glycoscience》2019,66(2):65
The cellulose binding domain (CBD) of cellulosome-integrating protein A from Clostridium thermocellum NBRC 103400 was genetically fused to FMN-dependent NADH-azoreductase (AZR) and glucose 1-dehydrogenase (GDH) from Bacillus subtilis. The fusion enzymes, AZR-CBD and CBD-GDH, were expressed in Escherichia coli Rosetta-gami B (DE3). The enzymes were purified from cell-free extracts, and the specific activity of AZR-CBD was 15.1 U/mg and that of CBD-GDH was 22.6 U/mg. AZR-CBD and CBD-GDH bound strongly to 0.5 % swollen cellulose at approximately 95 and 98 % of the initial protein amounts, respectively. After immobilization onto the swollen cellulose, AZR-CBD and CBD-GDH retained their catalytic activity. Both enzymes bound weakly to 0.5 % microcrystalline cellulose, but the addition of a high concentration of microcrystalline cellulose (10 %) improved the binding rate of both enzymes. A reactor for flow injection analysis was filled with microcrystalline cellulose-immobilized AZR-CBD and CBD-GDH. This flow injection analysis system was successfully applied for the determination of glucose, and a linear calibration curve was observed in the range of approximately 0.16–2.5 mM glucose, with a correlation coefficient, r, of 0.998. 相似文献
47.
48.
For decades, numerous artificial muscles have been proposed in order to implement beneficial features of biological muscles into robotics. Unfortunately, traditional artificial muscles experienced difficulties in imitating properties of the biological muscles due to mechanical and control issues. Recently, twisted and coiled polymer actuators (TCP) have been shown to produce large mechanical power via thermal stimulations and strong linearity. In this paper, a high-performance TCP thermally cycled by electrical heating and forced convective liquid cooling is designed and associated control algorithms are presented. We elaborate the model of the TCP that is simple, yet provides insight into how the electrical heating and the forced convective liquid cooling contribute to the TCP actuation. The proposed model is verified by experimental studies. Based on the proposed model, we design a feedforward–feedback controller and switching laws, which actively control the TCP in both the heating and cooling cycles. Furthermore, we extend our control methodology to agonist–antagonist TCPs. From the experimental studies, the proposed method is shown to be effective in both single TCP and antagonistic TCPs. 相似文献
49.
A multiphase dc‐dc converter is effective for miniaturization and achieving high‐power density in a switching power supply. However, its mathematical modeling becomes complex as the phase number of the circuit increases. This study proposes a new modeling method to derive a reduced‐order method in a simple manner. The frequency characteristics of the reduced‐order model are fit to those of the original mathematical model of the multiphase dc‐dc converter. Therefore, the efficacy of the proposed method is validated. 相似文献
50.
Okihashi M Kitagawa Y Akutsu K Obana H Hori S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(6):389-393
Residues of 17 pesticides in agricultural products were determined by LC/MS with an atmospheric pressure chemical ionization (APCI) interface in both positive and negative ion modes. Pesticides were extracted with acetonitrile, and the extracts were cleaned-up with a primary and secondary amine (PSA) mini-column eluted with acetone-hexane (1:1). Rice, orange and potato were spiked with the 17 pesticides at 0.1 microgram/g and analyzed by the proposed method. The average recoveries of these pesticides usually ranged from 70 to 98% and the relative standard deviations were usually around 10%. These results suggested that LC/MS with APCI could be used to determine the residue levels of the 17 pesticides in these crops. 相似文献