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121.
122.
Single-molecular switching phenomena in monolayer arrays of subphthalocyanine adsorbed on Cu(1 0 0) surface were investigated by scanning tunneling microscopy (STM) under ultrahigh vacuum. The molecules evaporated on the surface arranged in a square lattice taking the Cu(1 0 0)SubPc(5 × 5) epitaxy. During continuous STM imaging at fixed tunneling conditions the topography of the individual molecules spontaneously changed between the high and low states. This topographic change was attributed to orientational switching between the upward and downward adsorption of the axial Cl atom of the molecule on the Cu surface. Molecular energy calculations and statistical thermodynamic evaluation concluded that the tip-triggered disturbance in the close-packed molecular array induced the molecular rearrangement accompanied with the stochastic orientational switching. 相似文献
123.
Structural evolution of the solution of tetraethoxysilane hydrolyzed with [H2O]/[Si(OC2H5)4] = 2 under acidic condition has been investigated by rheological measurements. It was found that the solution behaves as a Newtonian liquid up to a highly viscous state and shows spinnability before gelation when the evaporation of the solvent is allowed during gelation reaction. On the other hand, the solution behaved as a non-Newtonian liquid in the viscous state, showing no spinnability when the evaporation of the solvent was not allowed during the reaction. It was indicated from the Casson plots that the spinnable solution prepared in the open system has no yield stress up to highly viscous states, whereas the non-spinnable solution prepared in the closed system has a yield stress at viscous states. It was proposed that the increase in viscosity of the open system solution is attributable to the concentration of the sol particles whereas that of the closed system solution is attributable to the formation of the three dimensional network in the solution. 相似文献
124.
Hisao Watanabe 《Applied Mathematics and Optimization》1989,20(1):81-96
In this paper we consider the convergence of the solutions to a sequence of partial differential equations of parabolic type with rapidly oscillating coefficients to the solutions of a stochastic partial differential equation. We use the martingale method and the characteristic functional to prove that the martingale problem has a unique solution. Our emphasis is in treating strongly mixing noises.This research was partially supported by Stifting Volkswagenwerk through Forschungszentrum BiBoS Universität Bielefeld and Grant-in-Aid for General Scientific Research (C) 61540162, the Ministry of Education, Science and Culture (Japan). Presented at the International Workshop on Diffusion Approximations and Related Topics, IISA, Laxenburg, Austria, 29 June to 3 July 1987. 相似文献
125.
Kiyoshi Kitahara Hiromitsu Yanagimoto Namiko Nakajima Hisao Nishi 《Journal of heterocyclic chemistry》1992,29(1):167-169
The synthesis of 4,11-dialkylthioquinacridones and 5,12-dialkyl-4,11-dialkylthioquinacridone from o-alkylthioanilines and diethyl 2,5-dioxo-1,4-cyclohexanedicarboxylate is described. These compounds are easily soluble in organic solvents in contrast to unsubstituted quinacridone. 相似文献
126.
127.
If a space-time is vicious at a some point, then it is totally vicious. 相似文献
128.
Hisao Yoshihara 《manuscripta mathematica》1992,75(1):279-291
Let K be a purely trancendental extension of a field k with two variables. We want to classify fields {L}, which are quadratic
extension of K. First we prove the existence of a normal form of the defining equation of L. Then we give a rough classification
and several results. Lastly we mention of an application to the theory of plane curves. 相似文献
129.
Tetsuo Asano Mark de Berg Otfried Cheong Leonidas J. Guibas Jack Snoeyink Hisao Tamaki 《Discrete and Computational Geometry》2003,30(4):591-606
We consider the problem of finding low-cost spanning trees for sets
of $n$ points in the plane, where the cost of a spanning tree is
defined as the total number of intersections of tree edges with
a given set of $m$ barriers. We obtain the following results:
(i) if the barriers are possibly intersecting line segments,
then there is always a spanning tree of cost
$O(\min(m^2,m\sqrt{n}))$; (ii) if the barriers are disjoint line segments,
then there is always a spanning tree of cost $O(m)$; (iii) ] if the barriers are disjoint
convex objects,
then there is always a spanning tree of cost $O(n+m)$.
All our bounds are worst-case optimal, up to multiplicative constants. 相似文献
130.
Abe K Amako K Arai Y Asano Y Chiba M Chiba Y Daigo M Emura T Endo I Fukawa M Fukui T Fukushima Y Haba J Haidt D Hayashibara I Hemmi Y Higuchi M Hirose T Hojyo Y Homma Y Hoshi Y Ikegami Y Ishihara N Kamitani T Kanematsu N Kanzaki J Kikuchi R Kondo T Koseki T Kubo K Kurashige H Matsui T Minami M Miyake K Mori S Nagashima Y Nakamura T Nakano I Odaka S Ogawa K Ohama T Ohsugi T Ono A Osabe H Saito H Sakae H Sakamoto H Sakamoto S Sakano M Sakuda M Sasao N Sato M Shioden M Shirai J Suekane F 《Physical review letters》1988,61(8):915-918