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61.
The oxygen content of silicon nitride with 1 mol% Y2 O3 —Nd2 O3 additive was measured after firing to determine the compositional change during gas-pressure sintering. Oxygen content decreases from 2.5 to 0.94 wt% during firing for 4 h at 1900°C and 10-MPa pressure in N2 . This decrease in oxygen results from the release of SiO gas generated by a thermaldecomposition reaction between Si3 N4 and SiO2 . The resultant sintered silicon nitride material contains less than 1 wt% oxygen. 相似文献
62.
Yannhui Lou Yuta Okawa Zhaokui Wang Shigeki Naka Hiroyuki Okada 《Organic Electronics》2013,14(3):1015-1020
The electron transport capability of 4,4′-bis[N-(1-napthyl)-N-phenyl-amino] biphenyl (α-NPD) was investigated by fundamental physical measurements named as current–voltage (I–V) electrical property evaluation and displacement current measurement (DCM). In electron-dominated devices, the I–V characteristics of α-NPD were similar as that of (8-hydroxyquinolino) aluminum (Alq3) owing to their same order of electron mobilities. The interface of Al/LiF and α-NPD was proven to be an Ohmic contact through the evaluation of I–V characteristics at low bias regime (<3 V). And an electron injection barrier, 0.21 eV, at Al/LiF/α-NPD was obtained by extrapolating the temperature dependent I–V curves. The electron transport behavior in α-NPD film was further confirmed by DCM evaluations. Furthermore, an efficient white organic light emission device was successfully fabricated by using α-NPD as hole transport layer and electron transport layer, respectively. 相似文献
63.
Manabu Nishijima Irina D. Gocheva Shigeto Okada Takayuki Doi Jun-ichi Yamaki Tetsuaki Nishida 《Journal of power sources》2009,190(2):558-562
Fluorine compounds have high discharge voltage due to its highly ionic metal-ligand bonds. In them, perovskite-type metal trifluorides with corner sharing matrix have large bottlenecks of diffusion pathways for intercalants. Iron trifluoride composites (FeF3-C) prepared by planetary ball milling with carbon showed reversible charge/discharge behavior not only for Li, but also for Na anodes. X-ray diffraction and 57Fe Mössbauer spectroscopy were applied to characterize the electrochemical properties of FeF3 vs. Li and Na anodes. The cathode performances of the other commercially available transition metal trifluorides such as MF3 (M = Ti, V, Mn, Co) have been also investigated. 相似文献
64.
65.
Tsuyoshi Nomura Masahiro Ikeda Seiji Ishiyama Kazuhide Mita Toshiki Tamura Takahiro Okada Kazuhito Fujiyama Akihiro Usami 《Journal of Bioscience and Bioengineering》2010,110(4):386-391
In insects, β-N-acetylglucosaminidase (GlcNAcase) participates in critical physiological processes such as fertilization, metamorphosis, and glycoconjugate degradation. Insects produce glycoproteins carrying paucimannosidic-type N-glycans, the terminal GlcNAc residue of which is cleaved by a GlcNAc-linkage specific GlcNAcase, also known as the fused lobes (FDL) protein. To obtain information on the structure of GlcNAcases and insight into their contribution to physiological processes, we cloned Bombyx mori FDL (BmFDL) from silkworm larvae. The full-length cDNA (1.9 kb) encoded a protein of 633 amino acids with 42% amino acid sequence identity to Drosophila melanogaster FDL (DmFDL). Recombinant BmFDL cleaved only β-1,2-linked GlcNAc residues from the α-1,3 branch of biantennary N-glycan. This substrate specificity was similar to that of DmFDL. Microsomal FDL activity was inhibited by anti-BmFDL antibodies. Taken together, our results suggest that BmFDL is a N-glycan-processing GlcNAcase in B. mori. 相似文献
66.
Y. Yamada K. Tajima S. Bao M. Okada K. Yoshimura 《Solar Energy Materials & Solar Cells》2009,93(12):2143-8
The hydrogenation and dehydrogenation switching processes of Pd thin films were analyzed by measuring in situ in real time the variation in ellipsometric Ψ and Δ during hydrogenation and dehydrogenation using spectroscopic ellipsometry. The hydrogenation proceeded from the film surface and a mixture layer of metal and hydride was formed at the surface. With time elapse, the thickness of the mixture layer increased rapidly. After the whole Pd metal layer transformed to the mixture layer, the concentration of hydride in the mixture layer increased. Finally, the concentration reached 1; the whole Pd in the mixture layer was hydrogenated, and the hydrogenation of Pd was complete. On the other hand, the dehydrogenation proceeded in a way completely opposite to the hydrogenation process; the concentration of hydride in the mixture layer decreased, Pd metal layer was formed at the interface between the film and the substrate, and the whole layer returned to Pd metal. The dehydrogenation proceeds much faster than hydrogenation. 相似文献
67.
Ecto-ATPase (ecto-adenosine triphosphatase), a key enzyme of cardiac metabolism, is responsible for modulation of the concentration of extracellular nucleotides in the heart. We present methodology consisting of the combined use of biochemical and histocytochemical techniques to study its properties. Using samples from essentially the same preparation, we applied biochemistry and histocytochemistry to determine biochemical characteristics of ecto-ATPase and an in situ localization of its reactivity. Our results indicated that detected enzyme resists fixation, depends on divalent ions, and hydrolyzes ATP, but not AMP or ADP-beta-S. Reaction product of the enzyme activity was found confined to the extracellular surface of the plasma membrane of cardiac myocytes and endothelial cells due to the corresponding orientation of the enzyme active sites. Experiments using an inhibitor justified specificity of the reaction. When used together with molecular biological and immunocytochemical techniques, the present methodological approach should be capable of yielding important information about the actual ability of ecto-ATPase to operate. 相似文献
68.
Robots have been envisaged as both workers and partners of humans from the earliest period in their history. Therefore, robots
should become artificial entities that can socially interact with human beings in social communities. Recent advances in technology
have added various functions to robots. The development of actuators and grippers show us infinite possibilities for factory
automation, and robots can now walk and perform very smoothly. All of these functions have been developed as solutions for
improving robot movement and performance. However, there are many remaining problems in the communication between robots and
humans. Communication robots provide one approach to the realization of embodied interfaces. Furthermore, the unsolved problems
of human–robot communication can be clarified by adopting the concept of subtractive methods. In this article, we consider
the minimal design of robots from the viewpoint of designing communication. By minimal design, we mean eliminating the nonessential
portions and keeping only the most fundamental functions. We expect that the simple and clean nature of minimally designed
objects will allow humans to interact with these robots without becoming uninterested too quickly. By exploiting the fact
that humans have “a natural dislike for the absence of reasoning,” artificial entities built according to minimal design principles
can extract the human drive to relate with others. We propose a method of designing a robot that has “character” and is situated
in a social context from the viewpoint of minimal design.
This work was presented in part at the 10th International Symposium on Artificial Life and Robotics, Oita, Japan, February
4–6, 2005 相似文献
69.
Okada T 《Analytical chemistry》2000,72(6):1307-1314
The interactions between ion-exchange resins and counterions consist of several mechanisms, such as ion-pair formation between active sites and counterions, specific adsorption, solvation changes, and double-layer accumulation. The double-layer accumulation of ions, which is a typical nonstoichiometric mechanism, is an important factor governing overall ion-exchange chromatographic retention when a major part of the stationary-phase surface is in contact with eluent flows. Nonporous stationary phases, where solutes are accessible to the surfaces by convection as well as by diffusion, possibly highlight this nonstoichiometric contribution through the coupling of a flow profile with an electrostatic potential function. The retention of ions on nonporous stationary phases has been interpreted by a model derived on the basis of the Poisson-Boltzmann equation including solvation change terms. Unusual retention behaviors have been confirmed only for anions, and can be explained by the model including the assumption that anions undergo solvation changes in a thin layer (approximately 5 nm thickness) at the vicinity of the stationary phase; the thickness should be a function of eluent flow rates. This strongly suggests that there is a difference in solvation nature between cations and anions. It can be inferred that water molecules interacting with polymer domains of the stationary phase behave like single molecules and cannot form a stable hydration shell around an anion as usually seen in bulk solution. 相似文献
70.
Using a 150-mum-thick CsLiB(6)O(10) crystal, we produced 100-fs, >200-nJ light pulses tunable between 175 and 180 nm by sum-frequency generation at a 1-kHz repetition rate with an all-solid-state laser system mixing the fourth harmonic of a femtosecond Ti:sapphire regenerative amplifier and the idler pulse from a traveling-wave optical parametric amplifier. 相似文献