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101.
本文证明了d2k =δ2k =d2k ≥b2k,其中d2k ,δ2k , b2k分别表示A(BlMp)在lNq下的Kolmogorov,线性,Bernstein 2k-宽度,d2k 表示AT(BlN相似文献
102.
本文采用解析的方法计算了应变Si1-xGex层中p型杂质电离度与Ge组分x、温度T以及掺杂浓度N的关系.发现常温时,在同一Ge组分下,随着掺杂浓度的升高,杂质的电离度的先变小,而后又迅速上升到1.在同一掺杂浓度下,轻掺杂时,杂质的电离度随Ge组分的增加先变大,而后几乎不变;重掺杂时,杂质电离能变为0后,杂质电离度为1.低温下,轻掺杂时,载流子低温冻析效应较为明显,杂质的电离度普遍较小,当掺杂浓度大于Mott转换点时,载流子冻析效应不再明显,电离率迅速上升到1.在同一Ge组分下,随着掺杂浓度的升高,杂质的电离度先变小,后变大,而后又迅速上升到1.在同一掺杂浓度下,轻掺杂时,杂质的电离度随Ge组分的增加变大;重掺杂时,杂质电离能变为0后,杂质电离度为1. 相似文献
103.
104.
Considering a plane hyperbolic system with time-periodic coefficients, we construct a version of the direct Lyapunov method with the condition on the derivative of the Lyapunov functional along the trajectories of the system which is weakened by use of periodicity of the coefficients. We exhibit an illustrative example. 相似文献
105.
The attention of the present paper was devoted to nondestructive evaluation of masonry structures with a Focal Plane Array infrared camera. Tests were carried out in laboratory on specimens, which simulated one- and two-layer structures, with defects of different geometry and nature and located at different depths. The defects detection was analysed through a cause/effect relationship between the characteristics of defects and hosting material and the observed defect thermal signature, or contrast, on the hosting material. 相似文献
106.
E. S. Voropai M. P. Samtsov K. N. Kaplevskii A. A. Maskevich V. I. Stepuro O. I. Povarova I. M. Kuznetsova K. K. Turoverov A. L. Fink V. N. Uverskii 《Journal of Applied Spectroscopy》2003,70(6):868-874
Comparative analysis of the absorption and fluorescence spectra and fluorescence excitation spectra of thioflavin T (ThT) in various solvents and in the composition of amyloid fibrils has shown that ThT, when excited in the region of the long-wavelength absorption band, fluoresces in the spectral region with a maximum at 478–484 nm. The appearance in aqueous and alcohol solutions of a fluorescence band with a maximum near 440 nm has been attributed to the presence in the composition of the ThT preparations of an impurity with an absorption band in the 340–350-nm range. The literature data showing that in glycerol ThT has a wide fluorescence spectrum with two maxima are due to the artifact connected with the use of a high concentration of the dye. It has been suggested that the cause of the low quantum yield of ThT aqueous and alcohol solutions is the breakage of the system of conjugated bonds due to the reorientation of the benzothiozole and benzaminic rings of ThT in the excited state with respect to one another. The main factor determining the high quantum yield of fluorescence of ThT incorporated in fibrils is the steric restriction of the rotation of the rings about one another under these conditions. The suggestions made have been verified by the quantum-chemical calculation of the ThT molecule geometry in the ground and excited states. 相似文献
107.
We study linear dynamical systems with multidimensional time in Banach spaces. Using Taylor functional calculus we prove that under additional assumptions hyperbolic systems have shadowing property. 相似文献
108.
CCD光谱谱线标定方法研究 总被引:9,自引:5,他引:4
CCD作为光谱分析和测色仪器的光谱接收器件 ,光谱谱线定位受单色仪狭缝和CCD光敏元尺寸影响。提出采用最小二乘法做曲线拟合和质心法来确定光谱线在CCD上的精确定位 ,使光谱谱线的定位精度得到提高 ,并且不受CCD光敏元尺寸限制。实验结果表明 ,两种方法对光谱线的定位 ,具有重复性高 ,稳定性好等特点。在定位精度上 ,两者具有一致性。 相似文献
109.
Instability of Solitary Waves in Nonlinear Composite Media 总被引:1,自引:0,他引:1
Ye Zhao 《应用数学学报(英文版)》2007,23(2):311-318
In this paper,we investigate a class of Hamiltonian systems arising in nonlinear composite media.By detailed analysis and computation we obtain a decaying estimates on the semigroup and prove the orbitalinstability of two families of explicit solitary wave solutions (slow family in anisotropic case and solitary wavesin isotropic case),which theoretically verify the related guess and numerical results. 相似文献
110.
A generalized linear differential equation in a Banach space is studied. The construction of a phase space and solutions with the help of the spectral theory of linear operators, ergodic theorems, and degenerate semigroups of linear operators is carried out. 相似文献