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991.
王现 《Annals of Differential Equations》1996,(4)
GLOBALANALYSISOFACLASSOFCUBICSYSTEMSWangXian(王现)(NanjingUniversity,南京大学,邮编:210093)Abstract:Thepapergivesacompletegolbalphasep... 相似文献
992.
廖公夫 《数学物理学报(B辑英文版)》1996,(1)
ACHARACTERIZATIONOFTHESOLUTIONSOFp-ORDERFEIGENBAUM'SFUNCTIONALEQUATIONWITHTOPOLOGICALENTROPY0(廖公夫)¥LiaoGongfu(Dept.ofMath.,Ji... 相似文献
993.
本文定义了管范畴上的一些算子,研究了它们的一些性质,给出了循环单列代数的Ringel-Hall代数H(T)的结构常数FML,N的一个计算公式.利用这些算子和这个公式,我们得到了其合成代数C(T)及半单模[l(?)i=1nSi](t∈Z+)在H(T)中的一些中心化子.事实上,它们是H(T)的中心元素,且是H(T)在其合成代数C(T)上代数无关的生成元. 相似文献
994.
995.
A. Li S.C. Liu K.W. Su Y.L. Liao S.C. Huang Y.F. Chen K.F. Huang 《Applied physics. B, Lasers and optics》2006,84(3):429-431
We demonstrate the first use of InGaAsP quantum wells as a saturable absorber in the Q-switching of a diode-pumped Nd-doped 1.3 μm laser. The barrier layers of the InGaAsP quantum-well device are designed to be a strong absorber for the suppression of the transition channel at 1.06 μm. With an incident pump power of 1.8 W, an average output power of 160 mW with a Q-switched pulse width of 19 ns at a pulse repetition rate of 38 kHz was obtained. PACS 42.60.Gd; 42.55.Xi; 42.65.Re 相似文献
996.
M.K. Kuo T.R. Lin B.T. Liao C.H. Yu 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):199
Strain distribution and optical properties in a self-assembled pyramidal InAs/GaAs quantum dot grown by epitaxy are investigated. A model, based on the theory of linear elasticity, is developed to analyze three-dimensional induced strain field. In the model, the capping material in the heterostructure is omitted during the strain analysis to take into account the sequence of the fabrication process. The mismatch of lattice constants is the driving source of the induced strain and is treated as initial strain in the analysis. Once the strain analysis is completed, the capping material is added back to the heterostructure for electronic band calculation. The strain-induced potential is incorporated into the three-dimensional steady-state Schrödinger equation with the aid of Pikus–Bir Hamiltonian with modified Luttinger–Kohn formalism for the electronic band structure calculation. The strain field, the energy levels and wave functions are found numerically by using of a finite element package FEMLAB. The energy levels as well as the wave functions of both conduction and valence bands of quantum dot are calculated. Finally, the transition energy of ground state is also computed. Numerical results reveal that not only the strain field but also all other optical properties from current model show significant difference from the counterparts of the conventional model. 相似文献
997.
Jie Bian Sheng‐Rong Ye Lin‐Xian Feng 《Journal of Polymer Science.Polymer Physics》2003,41(18):2135-2144
The crystallization behavior of poly(ethylene terephthalate) (PET) with disodium terephthalate (DST) as nucleating agent was investigated. A detailed analysis of the crystallization course from the melt was made with the Avrami expression. The results demonstrated that DST additive can promote the PET crystallization rate in its entire crystallizable temperature range, and the acceleration degree of DST decreases with increasing temperature after a temperature higher than 180 °C. The values of the Avrami exponent indicated that the crystallization mode in Avrami theory is not suitable for the crystallization of these polymers, and the mechanism of the heterogeneous nucleation on PET crystallization is discussed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2135–2144, 2003 相似文献
998.
Silica nanoparticles were first used as the carrier for the porcine pancreas lipase (PPL) immobilization. The result of transmission electron microscopy (TEM) showed that the immobilized lipase was still in nanosize after enzyme immobilization. The ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) catalyzed by this immobilized PPL (IMPPL) was explored. 1H NMR spectra suggested no evidence of decarboxylation during propagation. Influences of IMPPL concentration and reaction temperature on the molecular weight and yield of poly(DTC) were studied. The recovery and reuse of IMPPL for the ring-opening polymerization of DTC was also investigated. The recycling IMPPL showed even higher catalytic activity and a higher molecular weight of polycarbonate could be achieved. 相似文献
999.
光学孤子在色散缓变光纤中的传输特性研究 总被引:8,自引:2,他引:6
从理论上分析了超短光脉冲在色散缓变光纤中无畸变传输所要求的色散变化关系,设计了单模缓变光纤结构参数。数值模拟验证了理论分析结果,指出改变光纤色散参数完全可以克服光纤损耗对光孤子波形的畸变影响。 相似文献
1000.
A new fixed point theorem and its applications 总被引:4,自引:0,他引:4
Xian Wu 《Proceedings of the American Mathematical Society》1997,125(6):1779-1783
In this paper, we first give a new fixed theorem of lower semicontinuous multivalued mappings, and then, as its applications we obtain some new equilibrium theorems for abstract economies and qualitative games.