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991.
992.
In an OCT sensing system, the optical coherence length of the light source determines the spatial resolution, which is within the range of tens of micrometers. In this paper, by removing high-frequency noise with average operation and fitting the measured discrete sampled data with a continuous function, the theoretical resolution can be improved. The experimental results obtained show the short-term repeatability to be better than 0.4 μm after signal processing. 相似文献
993.
994.
Theoretical analysis of the DNA dynamics reveals that interaction between the single solitons and plane wave implies Smale-horseshoe chaos in the double helices. Solutions of the chaotic solitons are derived from a direct perturbation technique. It is demonstrated that to produce the bounded chaotic solitons, velocities of the solit ons nust be the same and equal to propagation velocity of the plane wave in DNA. The result shows that the DNA structure may be destroyed by the long action of an electromagnetic wave. It also supplies a useful method for controlling the velocities and unboundedness of the DNA motion in a tumour cell by using a plane wave.`` 相似文献
995.
996.
A graph Г is said to be G-locally primitive, where G is a subgroup of automorphisms of Г, if the stabiliser Ga of a vertex α acts primitively on the set Г( α ) of vertices of Г adjacent to α. For a finite non-abelian simple group L
and a Cayley subset S of L, suppose that L ⊴ G ⩽ Aut( L), and the Cayley graph Г = Cay ( L, S) is G-locally primitive. In
this paper we prove that L is a simple group of Lie type, and either the valency of Г is an add prine divisor of |Out(L)|, orL =PΩ
8
+
(q) and Г has valency 4. In either cases, it is proved that the full automorphism group of Г is also almost simple with the
same socle L. 相似文献
997.
Shaomei FANG Boling GUO Department of Mathematics Shaoguan University Shaoguan China Graduate School China Academy of Engineering Physics Beijing China Center for Nonlinear Studies Institute of Applied Physics Computational 《Communications in Nonlinear Science & Numerical Simulation》2001,6(2):107-110
Introduction In [if, the authors established the unique existence of the smooth solution for the couplednonlinear equations. These were proposed to describe the interaction process of internal longwaves. In [2], Ito proposed a recursion operator by which he inferred that the equations possessinfinitely many symmetries and constants of motion. In [31, He established the existence ofa smooth solution to the system of coupled nonlinear KdV equations[41. We remark that'Schonbeh[sl dealt with a … 相似文献
998.
In order to use DNA for making molecular device, specific DNA patterns on a solid surface should be constructed. In this paper, we will show that the random interactions between the DNA segments and the solid surface play an important role in the final symmetric and asymmetric DNA patterns obtained by water flow. 相似文献
999.
SBA-15的二氧化钛改性及其光催化降解对氯苯酚 总被引:10,自引:0,他引:10
在“后合成”法在介孔二氧化硅SBA-15的孔壁表面键接了二氧化钛,并对其 结构进行了表征。改性后的SBA-15保持了规则的介孔结构,并在孔壁表面形成了 类似于锐钛型二氧化钛的Ti-O-Ti网络结构。光催化降解对氯苯酚的结果表明,经 过两次二氧化钛键接的样品表现出较高的光催化效率。但是由于对酚、醌等中间产 物的强烈吸附以及孔道中反应物质的扩散速度慢,使得其光催化活性略低于纯的锐 钛型二氧化钛。 相似文献
1000.