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81.
We have demonstrated for the first time that the self-spreading of supported lipid bilayers can be controlled by the temporal switching of an electric field applied between nanogap electrodes. To account for this phenomenon, we propose an electrostatic trapping model in which an electric double layer plays an important role. The validity of this mechanism was verified by the dependence of self-spreading on the nanogap width and the ionic concentration of the electrolyte. Our results provide a promising tool for the temporal and spatial control of lipid bilayer formation for nanobio devices. 相似文献
82.
The nonlinear normal modes of a horizontally supported Jeffcott rotor are investigated. In contrast with a vertically supported
rotor, there are localized and nonlocalized nonlinear normal modes because the linear natural frequencies in the horizontal
and vertical directions are slightly different due to both gravity and the nonlinearity of restoring force. Reflecting such
nonlinear normal modes, the frequency response curves are characterized in the primary resonance. In the case where the eccentricity
is small, i.e., the response amplitude is small, the whirling motion is localized in the horizontal or vertical direction
in the resonance. On the other hand, when the eccentricity is large, two kinds of whirling motion, which are localized in
the vertical direction and nonlocalized in any direction, coexist simultaneously in a region of rotational speed. Experiments
are conducted, and the theoretically predicted nonlinear responses based on localized and nonlocalized nonlinear normal modes
are observed. 相似文献
83.
Shigeo Taguchi Masahiko Yamamoto Naoki Surugaya Akira Kurosawa Toshiaki Hiyama Tatsuhiko Tanaka 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):435-441
A flow injection-based electrochemical detection system coupled to a solid-phase extraction column was developed for the determination of trace amounts of plutonium in low-active liquid wastes from spent nuclear-fuel reprocessing plants. The oxidation state of plutonium in a sample solution was adjusted to Pu(VI) by the addition of silver(II) oxide. A sample solution was made up in 3 mol L?1 HNO3 and loaded onto a column packed with UTEVA® with 3 mol L?1 HNO3 as the carrier. Plutonium(VI) was adsorbed onto the resin, and interfering elements were removed by rinsing the column with 3 mol L?1 HNO3. Subsequently, the adsorbed Pu(VI) was eluted with 0.01 mol L?1 HNO3, and then introduced directly into the flow-through electrolysis cell with boron-doped diamond electrode. The eluted Pu(VI) was detected by an electrochemical amperometric method at a working potential of 0.1 V (vs. Ag/AgCl). The current produced on reduction of Pu(VI) was continuously monitored and recorded. The plutonium concentration was calculated from the relationship between the peak area and concentration of plutonium. The relative standard deviation of ten analyses was 1.1% for a plutonium solution of 25 μg L?1 containing 50 ng of Pu. The detection limit calculated from three-times the standard deviation was 0.82 μg L?1 (1.6 ng of Pu). 相似文献
84.
Conversion of the formyl group at the 7-position in chlorophyll (Chl) b to the methyl group via the hydroxymethyl group is biologically important in Chl b degradation. To clarify the effects of the 7-substituents on demetalation properties of chlorophyllous pigments in the early process of Chl b degradation, we report demetalation kinetics of the zinc Chl derivative possessing a 7-hydroxymethyl group, which is a good model compound of the intermediate molecule in the early process of Chl b degradation, under acidic conditions, and compare its properties with those of zinc Chl derivatives possessing a methyl and a formyl group, which are model compounds of Chls a and b, respectively. Demetalation rate constants of 7-hydroxymethyl zinc chlorin were much larger than those of 7-formyl zinc chlorin, but were slightly smaller than those of 7-methyl zinc chlorin. The activation energy for demetalation reaction of 7-formyl zinc chlorin was larger than those of other derivatives. Demetalation rate constants of 7-deformyl-7-hydroxymethyl Chl b were also larger than those of Chl b, and were similar to those of Chl a. These indicate that the 7-hydroxymethyl group in the chlorin macrocycle has a smaller effect on demetalation compared with the 7-formyl group. 相似文献
85.
Shona Banjo Eiko Nakasuji Tatsuhiko Meguro Prof. Dr. Takaaki Sato Prof. Dr. Noritaka Chida 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(33):7941-7947
A copper-catalyzed electrophilic amidation of aryltrifluoroborates with use of N-methoxyamides is reported. The reaction shows high functional group compatibility derived from two distinct features: 1) the high stability of the N-methoxyamides and 2) the nonbasic mild conditions in the presence of LiCl. The developed method can also be applied to the synthesis of enamides, which are widely distributed in natural products. Preliminary mechanistic studies suggest that the initial step is the transmetalation of the aryltrifluoroborate by the assistance of LiCl, and the resulting aryl copper intermediate provides the anilide through non-SN2 oxidative addition to the N-methoxyamide and subsequent reductive elimination. 相似文献
86.
Quasi-orthodox semigroups with inverse transversals 总被引:9,自引:0,他引:9
Tatsuhiko Saito 《Semigroup Forum》1987,36(1):47-54
87.
Tatsuhiko Yagasaki 《Proceedings of the American Mathematical Society》1999,127(9):2727-2734
Suppose is a connected Riemann surface. Let denote the homeomorphism group of with the compact-open topology, and denote the subgroup of quasiconformal mappings of onto itself, and let and denote the identity components of and respectively. In this paper we show that the pair is an -manifold, and determine their topological types.
88.
A note on regular semigroups with inverse transversals 总被引:7,自引:0,他引:7
Tatsuhiko Saito 《Semigroup Forum》1986,33(1):149-152
89.
Fujioka S Sunahara A Nishihara K Ohnishi N Johzaki T Shiraga H Shigemori K Nakai M Ikegawa T Murakami M Nagai K Norimatsu T Azechi H Yamanaka T 《Physical review letters》2004,92(19):195001
A scheme to suppress the Rayleigh-Taylor instability has been investigated for a direct-drive inertial fusion target. In a high-Z doped-plastic target, two ablation surfaces are formed separately-one driven by thermal radiation and the other driven by electron conduction. The growth of the Rayleigh-Taylor instability is significantly suppressed on the radiation-driven ablation surface inside the target due to the large ablation velocity and long density scale length. A significant reduction of the growth rate was observed in simulations and experiments using a brominated plastic target. A new direct-drive pellet was designed using this scheme. 相似文献
90.