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941.
Yusuke Hamabe Sungbong Jung Hikotaro Suzuki Naoto Koizumi Muneyoshi Yamada 《Journal of synchrotron radiation》2010,17(4):530-539
Ni species on the spent NiMo catalyst from ultra‐deep hydrodesulfurization of gas oil in a commercial plant were studied by Ni K‐edge EXAFS and TEM measurement without contact of the catalysts with air. The Ni–Mo coordination shell related to the Ni–Mo–S phase was observed in the spent catalyst by quasi in situ Ni K‐edge EXAFS measurement with a newly constructed high‐pressure chamber. The coordination number of this shell was almost identical to that obtained by in situ Ni K‐edge EXAFS measurement of the fresh catalyst sulfided at 1.1 MPa. On the other hand, large agglomerates of Ni3S2 were observed only in the spent catalyst by quasi in situ TEM/EDX measurement. MoS2‐like slabs were sintered slightly on the spent catalyst, where they were destacked to form monolayer slabs. These results suggest that the Ni–Mo–S phase is preserved on the spent catalyst and Ni3S2 agglomerates are formed by sintering of Ni3S2 species originally present on the fresh catalyst. 相似文献
942.
Ken Takayama Senri Soma Taiji Inoue Hideaki Kakinuma Takashi Haraguchi Kaoru Suzuki 《Applied Physics A: Materials Science & Processing》2010,101(4):727-733
Phosphorus-doped diamond-like carbon (DLC) films were deposited on quartz and p-type silicon (p-Si) substrates by pulsed-laser
deposition. Open-circuit voltage (V
oc) and short-circuit density (I
sc/cm2) from a heating process converted from one type of electrode to another and the two types of electrode pattern are shown
by the V–I characteristics. The first heating process was by a ceramic heater, and the other was by an infrared heater. We adopted two
electrode patterns, from a bipectinate electrode and a plot pattern electrode, to measure electric photovoltaic characteristics.
We were able to upgrade V
oc and I
sc/cm2 to 35∼45 mV, and 0.24 μA/cm2, respectively, under infrared heating. V
oc by the plot pattern electrode was over 2 V under infrared heating and ceramic heating did not match this on deposition by
the PLD method. 相似文献
943.
We propose a new interpolation technique for the CIP method applied to curvilinear coordinates. The CIP method can hardly maintain third-order accuracy on curvilinear coordinates. The reason for the degeneracy in accuracies has not been discussed in detail. This paper reveals the problems of the CIP method on curvilinear coordinates and presents an improved CIP method to solve the advection equation accurately. The features of the presented method are: (1) the metric computation on the upwind stencil is defined in the same manner as in the advection phase of the CIP method; and (2) gradient values in the physical domain in the computation on the curvilinear coordinates are used. Various test problems show that the improved CIP method has approximate third-order accuracy. 相似文献
944.
New germanosilicate glasses giving the crystallization of yttrium iron garnet Y3Fe5O12 (YIG) and Bi-doped YIG, 23Na2O-xBi2O3-(12−x)Y2O3-25Fe2O3-20SiO2-20GeO2 (mol%), are developed, and the laser-induced crystallization technique is applied to the glasses to pattern YIG and Bi-doped YIG crystals on the glass surface. It is clarified from the Mössbauer effect measurements that iron ions in the glasses are present mainly as Fe3+. It is suggested from the X-ray diffraction analyses and magnetization measurements that Si4+ ions are incorporated into YIG crystals formed in the crystallization of glasses. The irradiations (laser power: 32-60 mW and laser scanning speed: 7 μm/s) of continuous wave Yb:YVO4 fiber laser (wavelength: 1080 nm) are found to induce YIG and Bi-doped YIG crystals, indicating that Fe3+ ions in the glasses act as suitable transition metal ions for the laser-induced crystallization. It is suggested that YIG and Bi-doped YIG crystals in the laser irradiated part might orient. The present study will be a first step for the patterning of magnetic crystals containing iron ions in glasses. 相似文献
945.
Ni-P alloy-carbon black (CB) composite films were fabricated by electroplating and their microstructures and properties were examined. The CB and phosphorus contents of the composite films were also investigated. The CB particles were found to be embedded in the Ni-P alloy matrix. The CB content in the deposits increased, reached a maximum value of 0.77 mass% with increasing CB concentration in the bath up to 10 g dm−3, and then decreased with a further increase in the CB concentration in the bath. Both before and after heat treatment, the composite films had higher hardnesses and lower friction coefficients than the Ni-P alloy films. Both before and after heat treatment, the friction coefficient of 0.77 mass% CB composite films was about half that of Ni-P alloy films without CB. 相似文献
946.
Michel Pierre Takashi Suzuki Haruki Umakoshi 《Journal of Applied Analysis & Computation》2018,8(3):836-858
We consider the asymptotic behavior for large time of solutions to reaction-diffusion systems modeling reversible chemical reactions. We focus on the case where multiple equilibria exist. In this case, due to the existence of so-called "boundary equilibria", the analysis of the asymptotic behavior is not obvious. The solution is understood in a weak sense as a limit of adequate approximate solutions. We prove that this solution converges in L^1 toward an equilibrium as time goes to infinity and that the convergence is exponential if the limit is strictly positive. 相似文献
947.
Yusuke Suzuki 《Discrete Mathematics》2010,310(1):6-11
We show that, for any given non-spherical orientable closed surface F2, there exists an optimal 1-planar graph which can be embedded on F2 as a triangulation. On the other hand, we prove that there does not exist any such graph for the nonorientable closed surfaces of genus at most 3. 相似文献
948.
Uchida H Song JM Suzuki S Nakazawa E Baba N Watanabe M 《The journal of physical chemistry. B》2006,110(27):13319-13321
To confirm the superiority of newly developed electrocatalyst layer (ECL) for polymer electrolyte fuel cells, three-dimensional dispersion states of Nafion ionomer in Pt/carbon black agglomerates were analyzed by electron tomography based on multiple TEM images taken at different tilt angles. Uniform distribution of the ionomer has been first observed, proving the high catalyst utilization in the new ECL distinctive from that of the conventional one. 相似文献
949.
Suzuki T 《Physical review letters》2006,96(21):214801
We develop an orbit theory for synchrotron oscillations using the orbit length, , as an independent variable. This is commonplace for static magnetic fields (storage rings). We extend this to the case of adiabatically varying magnetic fields (synchrotrons). Contrary to conventional treatments, betatron acceleration terms appear in both the energy and phase equations. We derive one-turn difference equations in the linear and adiabatic approximations. By a smooth approximation instead of the traveling-wave approximation, and by combining the two equations, we obtain a differential equation where the betatron acceleration terms are canceled. This equation is an extension of McMillan's equation to the case of strong-focusing synchrotrons. 相似文献
950.
Summary Members of the vascular endothelial growth factor (VEGF) family are crucial regulators of neovascularization and are classified as cystine knot growth factors that specifically bind cellular receptor tyrosine kinases VEGFR-1, VEGFR-2, and VEGFR-3 with high but variable affinity and selectivity. The VEGF family has recently been expanded and currently comprises seven members: VEGF-A, VEGF-B, placenta growth factor (PlGF), VEGF-C, VEGF-D, viral VEGF (also known as VEGF-E), and snake venom VEGF (also known as VEGF-F). Although all members are structurally homologous, there is molecular diversity among the subtypes, and several isoforms, such as VEGF-A, VEGF-B, and PlGF, are generated by alternative exon splicing. These splicing isoforms exhibit differing properties, particularly in binding to co-receptor neuropilins and heparin. VEGF family proteins play multiple physiological roles, such as angiogenesis and lymphangiogenesis, while exogenous members (viral and snake venom VEGFs) display activities that are unique in physiology and function. This review will highlight the molecular and functional diversity of VEGF family proteins. 相似文献