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排序方式: 共有1006条查询结果,搜索用时 31 毫秒
921.
Tatsuya Kitade Keisuke Kitamura Shigehiko Takegami Yoko Miyata Miwa Nagatomo Tomomi Sakaguchi Michiko Furukawa 《Analytical sciences》2005,21(8):907-912
A needle-type ultra micro silver/silver chloride reference electrode having a micro capillary with outer and inner diameters of 1.0 microm and 0.5 +/- 0.2 microm, respectively, was constructed. This micro reference electrode can be stuck into a living cell, and is applicable to use in very small environments, such as an electrochemical cell of an electrochemical scanning tunneling microscope or the detection portion of a micro-TAS. Excellent stability and repeatability of the micro reference electrode potential could be obtained by filling the micro capillary with agar gel containing 3.33 mol/L potassium chloride as a salt bridge, by covering the bare part of the silver wire on which silver chloride was deposited, and by electromagnetic shielding of the measurement cell and wire lead from the electromagnetic waves. The electrode showed stable potential for 7 days after its fabrication using 3.3 mol/L potassium chloride aqueous solution containing silver chloride as an internal electrolyte solution. The electrode exhibited constant electrode potential and excellent stability in test solutions of pH 5-9. The electrode potential of a commercial pH glass electrode measured against the micro reference electrode in standard pH buffer solutions was in good accordance with the Nernst equation. 相似文献
922.
Sunao Takahashi Mutsumi Sano Tetsuro Mochizuki Atsuo Watanabe Hideo Kitamura 《Journal of synchrotron radiation》2008,15(2):144-150
A procedure to predict the fatigue fracture life of high‐heat‐load components made of GlidCop has been successfully established. This method is based upon the Manson–Coffin equation with a cumulative linear damage law. This prediction was achieved by consolidating the results of experiments and analyses, and considered the effects of environment and creep. A low‐cycle‐fatigue test for GlidCop was conducted so that environment‐dependent Δ?t–Nf diagrams for any temperature could be prepared. A special test piece was designed to concentrate the strain in a central area locally, resulting in the low‐cycle‐fatigue fracture. The experiments were carried out by repeatedly irradiating a test piece with an electron beam. The results of the experiment confirmed that the observed fatigue life was within a factor of two when compared with the predicted fatigue life, yet located on the safer side. 相似文献
923.
Shoichi Sato Yoshihiro Kino Atsushi Shibata Masaru Nakamura Christian Krauns Yuh Shiohara 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):341-343
Crystals of the title compound, samarium barium copper oxide, were prepared by a modified top‐seeded solution‐growth method. The crystals thus prepared showed no superconductivity down to 4.2 K. A careful examination showed that the structure closely resembles that of tetragonal YBCO, and there is no atom mixing at the Ba or other sites, within experimental accuracy. A bond‐valence‐sum calculation at the Ba site also indicated the absence of Sm. Each site is fully occupied by a single atom, except for the oxygen site in the basal plane of the CuO6 octahedron. The occupancy of this oxygen site is significantly reduced [0.13 (2)], as is commonly observed in the 123 system. The atomic displacement parameters of the atoms in the CuO2 plane, as well as of the Sm atom, are very small, indicating that two equivalent CuO2 planes tightly sandwich the Sm atom. 相似文献
924.
A twin system for hydrogen absorption experiments has been constructed to replicate the phenomenon of heat and 4He generation by D2 gas absorption in nano-sized Pd powders reported by Arata and Zhang, and to investigate the underlying physics. For Pd⋅Zr oxide nano-powders, anomalously large energies of hydrogen isotope absorption, 2.4±0.2 eV/D-atom and 1.8±0.4 eV/H-atom, as well as large loading ratio of D/Pd=1.1±0.0 and H/Pd=1.1±0.3, respectively, were observed in the phase of deuteride/hydride formation. The sample charged with D2 also showed significantly positive output energy in the second phase after the deuteride formation. 相似文献
925.
926.
Saulius Juodkazis Vygantas Mizeikis Markas Sūdžius Hiroaki Misawa Kenji Kitamura Shunji Takekawa Eugene G. Gamaly Wieslaw Z. Krolikowski Andrei V. Rode 《Applied Physics A: Materials Science & Processing》2008,93(1):129-133
We study experimentally the formation of refractive index voxels (volume elements) in photorefractive LiNbO3 and LiTaO3 crystals illuminated with high irradiance femtosecond laser pulses. We used 150 fs pulses at 800 nm wavelength (energy 6–50 nJ)
tightly focused inside the crystals in a single shot regime. This resulted in a formation of a micrometer size region of elevated
refractive index, which may be used as memory bits in information storage/retrieval application. The maximum refractive index
change of 5×10−4 was recorded in undoped LiNbO3 at an average light intensity of ∼TW/cm2 that is close to the breakdown threshold. A simple setup for photorefractive recording and in situ monitoring of the refractive
index changes has been proposed.
M. Sūdžius leaves from: the Institute of Materials Science and Applied Research of Vilnius University, Lithuania. 相似文献
927.
In this paper, we propose new Euler flux functions for use in a finite-volume Euler/Navier–Stokes code, which are very simple, carbuncle-free, yet have an excellent boundary-layer-resolving capability, by combining two different Riemann solvers into one based on a rotated Riemann solver approach. We show that very economical Euler flux functions can be devised by combining the Roe solver (a full-wave solver) and the Rusanov/HLL solver (a fewer-wave solver), based on a rotated Riemann solver approach: a fewer-wave solver automatically applied in the direction normal to shocks to suppress carbuncles and a full-wave solver applied, again automatically, across shear layers to avoid an excessive amount of dissipation. The resulting flux functions can be implemented in a very simple and economical manner, in the form of the Roe solver with modified wave speeds, so that converting an existing Roe flux code into the new fluxes is an extremely simple task. They require only 7–14% extra CPU time and no problem-dependent tuning parameters. These new rotated fluxes are not only robust for shock-capturing, but also accurate for resolving shear layers. This is demonstrated by an extensive series of numerical experiments with standard finite-volume Euler and Navier–Stokes codes, including various shock instability problems and also an unstructured grid case. 相似文献
928.
Nagaoka K Isobe M Toi K Shimizu A Fujisawa A Ohshima S Nakano H Osakabe M Todo Y Akiyama T Nagashima Y Suzuki C Nishimura S Yoshimura Y Matsuoka K Okamura S 《Physical review letters》2008,100(6):065005
The internal behavior of fast ions interacting with magnetohydrodynamic bursts excited by energetic ions has been experimentally investigated in the compact helical system. The resonant convective oscillation of fast ions was identified inside the last closed-flux surface during an energetic-particle mode (EPM) burst. The phase difference between the fast-ion oscillation and the EPM, indicating the coupling strength between them, remains a certain value during the EPM burst and drives an anomalous transport of fast ions. 相似文献
929.
For soft-mode turbulence, which is essentially the spatiotemporal chaos caused by the nonlinear interaction between convective modes and Goldstone modes in electroconvection of homeotropic nematics, a type of order-disorder phase transition was revealed, in which a new order parameter was introduced as pattern ordering. We calculated the spatial correlation function and the anisotropy of the convective patterns as a 2D XY system because the convective wave vector could freely rotate in the homeotropic system. We found the hidden order in the chaotic patterns observed beyond the Lifshitz frequency f(L), and a transition from a disordered to a hidden ordered state occurred at the f(L) with the increase of the frequency of the applied voltages. 相似文献
930.
Mori M Wakamatsu H Tonogaki K Fujita R Kitamura T Sato Y 《The Journal of organic chemistry》2005,70(3):1066-1069
Isoquinoline derivatives were synthesized from cyclobutenylmethylamine derivatives having an alkyne moiety in a tether using a second-generation ruthenium carbene complex under ethylene gas in good yields. 相似文献