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21.
Let
d−1{(x1,…,xd)
d:x21+···+x2d=1} be the unit sphere of the d-dimensional Euclidean space
d. For r>0, we denote by Brp (1p∞) the class of functions f on
d−1 representable in the formwhere dσ(y) denotes the usual Lebesgue measure on
d−1,
and Pλk(t) is the ultraspherical polynomial.For 1p,q∞, the Kolmogorov N-width of Brp in Lq(
d−1) is given bythe left-most infimum being taken over all N-dimensional subspaces XN of Lq(
d−1).The main result in this paper is that for r2(d−1)2,where ANBN means that there exists a positive constant C, independent of N, such that C−1ANBNCAN.This extends the well-known Kashin theorem on the asymptotic order of the Kolmogorov widths of the Sobolev class of the periodic functions. 相似文献
22.
S. J. Cheng W. Sheng P. Hawrylak S. Raymond S. Studenikin A. Sachrajda Z. Wasilewski A. Babinski M. Potemski G. Ortner M. Bayer 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):211
We present results of calculations and experiments on electron–hole complexes in InGaAs/GaAs self-assembled quantum dots in high magnetic field (B). Due to hidden symmetries, the chemical potential of an N-exciton system at special B fields becomes insensitive to the exciton number as well as the magnetic field. This results in plateau regions of high intensity in measured magneto-PL spectrum. Theoretical calculations using exact diagonalization techniques successfully explain the measured magneto-photoluminescence spectrum with B fields up to 28 T. 相似文献
23.
24.
Weidong Gao Meiqiong Zhan Shuhai Fan Janda Shao Zheng-Xiu Fan 《Applied Surface Science》2005,250(1-4):195-202
The laser-induced damage (LID) behavior of narrow-band interference filters was investigated with a Nd:YAG laser at 1064 nm under single-pulse mode and free-running mode. The absorption measurement of such coatings was performed with surface thermal lensing (STL) technique. The damage morphologies under the two different laser modes were also studied in detail. It was found that all the filters exhibited a pass-band-center-dependent absorption and laser-induced damage threshold (LIDT) behavior, but the damage morphologies were diverse. The explanation was given with the analysis of the electric field distribution and the operational behavior of the irradiation laser. 相似文献
25.
A graph G is N2‐locally connected if for every vertex ν in G, the edges not incident with ν but having at least one end adjacent to ν in G induce a connected graph. In 1990, Ryjá?ek conjectured that every 3‐connected N2‐locally connected claw‐free graph is Hamiltonian. This conjecture is proved in this note. © 2004 Wiley Periodicals, Inc. J Graph Theory 48: 142–146, 2005 相似文献
26.
Geng Sheng WANG 《数学学报(英文版)》2005,21(5):1005-1014
This work is concerned with Pontryagin's maximum principle of optimal control problems governed by some non-well-posed semilinear heat equations. A type of approach to the non-well-posed optimal control problem is given. 相似文献
27.
相对论重离子碰撞实验中混合事件方法的研究 总被引:1,自引:0,他引:1
把RQMD(Relativistic Quantum Molecular Dynamics)产生器产生的数据输入作为原始事例取样,讨论了在比较复杂的背景情况下,一种新的混合事件方法,用以证实在相对论重离子碰撞实验中高能量激发共振态的存在.并以共振态重子Δ++为例演示了这一方法的应用. 相似文献
28.
A lithium(I) coordination polymer has been formed from LiClO4 and the 2,2′‐bipyrimidine (bpym) ligand in which each square pyramidal lithium(I) atom is coordinated in the basal plane by four nitrogen donor atoms derived from two bpym ligands and one water molecule at the apical position. These are connected into a layer structure via hydrogen‐bonding interactions involving the perchlorate anions. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
29.
报道了硅基有机微腔的电致发光(EL).该微腔由上半透明金属膜、中心有源多层膜和多孔硅分布Bragg反射镜(PS DBR)组成.半透明金属膜由Ag(20nm)构成,充当发光器件的负电极和微腔的上反射镜.有源多层膜由Al (1 nm) / LiF(05 nm) /Alq3/Alq3:DCJTB/NPB/CuPc/ITO/SiO2组成,其中的Al/LiF为电子注入层,ITO为正电极,SiO2为使正、负电极电隔离的介质层.该PS DBR是采用设备简单、成本低廉且非常省时的电化学腐蚀法用单晶Si来制备的;该PS
关键词:
电化学腐蚀
电致发光
窄峰发射
硅基有机微腔 相似文献
30.
XiWenHE HongShengGUO YuMeiJIA 《中国化学快报》2003,14(9):979-982
In order to obtain mechanically stable membrane for practical application, the imprinted polymer was synthesized in the pores of polyfluoromembrane, the binding and transport ability of the membrane were studied. 相似文献