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131.
Peng Feng 《Journal of Mathematical Analysis and Applications》2007,329(1):347-356
In this paper we establish the exact blow-up rate of the large solutions of a porous media logistic equation. We consider the carrying capacity function with a general decay rate at the boundary instead of the usual cases when it can be approximated by a distant function. Obtaining the accurate blow-up rate allows us to establish the uniqueness result. Our result covers all previous results on the ball domain and can be further adapted in a more general domain. 相似文献
132.
一类拟线性大系统的稳定性 总被引:1,自引:0,他引:1
彭晓林 《新疆大学学报(理工版)》1991,8(1):41-45
本文应用大系统的分解方法和一个推广的不等式,研究了一类拟线性大系统的稳定性问题,所得结果简洁、易于验证,且推导过程不复杂,最后给出了应用实例。 相似文献
133.
The general relation between the standard expansion coefficients and the beta function for the QCD coupling is exactly derived in a mathematically strict way. It is accordingly found that an infinite number of logarithmic terms are lost in the standard expansion with a finite order, and these lost terms can be given in a closed form. Numerical calculations, by a new matching-invariant coupling with the corresponding beta function to four-loop level, show that the new expansion converges much faster. 相似文献
134.
液态泡沫结构及其稳定性 总被引:2,自引:0,他引:2
液态泡沫由大量气泡密集堆积在少量的表面活性剂溶液中形成,是具有高度自组织结构的典型的软物质.文章从泡沫物理学角度简要介绍了液态泡沫的结构特征和稳定性方面的研究. 相似文献
135.
136.
137.
Y.-Q. Peng J.-H. Yang F.-P. Lu 《Applied Physics A: Materials Science & Processing》2006,83(2):305-311
Under the assumption of Gaussian energy distributions of the lowest unoccupied molecular orbital (LUMO) and the highest occupied
molecular orbital (HOMO), analytical expressions of generalized Einstein relation for electron and hole transport in doped
organic semiconductor thin films are developed. Numerical calculations show that, although traditional Einstein relation still
holds for low carrier concentrations, that is, the diffusion-coefficient-to-mobility ratio in units of kBT/q, with kB the Boltzmann’s constant, T the temperature and q the elementary charge, equals 1. But when the electron (hole) concentration
is high, the diffusion-coefficient-to-mobility ratio for electrons (holes) changes strongly with the electron (hole) concentration,
the doping level, the mean energy of LUMOs (HOMOs) of the dopant ELd (EHd) and the host EL (EH), as well as their variances. Dopants with ELd<EL (EHd>EH) affect the diffusion-coefficient-to-mobility ratio mainly in the range of low and middle carrier concentrations, while those
with ELd>EL (EHd<EH) have significant effect only in the range of high carrier concentrations. It was found that there can be a maximum in the
dependence of the diffusion-coefficient-to-mobility ratio on the quasi-Fermi energy or carrier concentration exist, for appropriate
values of the doping level, the mean energy and variance of LUMO or HOMO states of the dopant.
PACS 71.20.Rv; 72.90.+y; 73.50.-h 相似文献
138.
Effect of Alumina and Chromium Interlayers on Microstructures and Optical Properties of Thin Ag Films on Glass Substrates
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Effects of alumina and chromium interlayers on the microstructure and optical properties of thin Ag films are investigated by using spectrophotometry, x-ray diffraction and AFM. The characteristics of Ag films in Ag/glass, Ag/l2O3/glass and Ag/Cr/glass stacks are analysed. The results indicate that the insertion of an Al2O3 or Cr layer decreases the grains and influences the reflectance of Ag films. The reflectance of the Ag film can be increased by controlling the thickness of alumina interlayer. The stability of Ag films is improved and the adhesion of Ag films on glass substrates is enhanced by alumina as an interlayer. 相似文献
139.
本文研究固定设计下的半参数回归模型在相应变量Yi因受到某种随机干扰而被右截断且截断分布已知时,利用所获的截断观察定义了参数β和回归函数g(·)的估计,并证明了它们均具有强相合性. 相似文献
140.
Optical transmission properties of subwavelength planar fractals in terahertz (THz) frequency regime are studied by means of time-domain spectroscopy. The transmission spectra with multiple pass bands and stop bands are observed. The tunable photonic band gaps are realized by changing the angle between the principle axis of planar fractal and the polarization of THz wave. The possible application of the subwavelength optical component is discussed. We attribute the detected transmittance from subwavelength fractals to localized resonances. 相似文献