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1.
Hans TRIEBEL 《应用数学学报(英文版)》2004,(4)
The paper deals with multifractal quantities for some types of Radon measures,especiallyself-similar probability measures,and their relations to Besov spaces. 相似文献
2.
S. D. Gunapala S. V. Bandara J. K. Liu S. B. Rafol J. M. Mumolo C. A. Shott R. Jones J. Woolaway II J. M. Fastenau A. K. Liu M. Jhabvala K. K. Choi 《Infrared Physics & Technology》2003,44(5-6):411-425
A 9 μm cutoff 640 × 512 pixel hand-held quantum well infrared photodetector (QWIP) camera has been demonstrated with excellent imagery. A noise equivalent differential temperature (NEDT) of 10.6 mK is expected at a 65 K operating temperature with f/2 optics at a 300 K background. This focal plane array has shown background limited performance at a 72 K operating temperature with the same optics and background conditions. In this paper, we discuss the development of this very sensitive long-wavelength infrared camera based on a GaAs/AlGaAs QWIP focal plane array and its performance in quantum efficiency, NEDT, uniformity, and operability. In the second section of this paper, we discuss the first demonstration of a monolithic spatially separated four-band 640 × 512 pixel QWIP focal plane array and its performance. The four spectral bands cover 4–5.5, 8.5–10, 10–12, and 13.5–15 μm spectral regions with 640 × 128 pixels in each band. In the last section, we discuss the array performance of a 640 × 512 pixel broad-band (10–16 μm full-width at half-maximum) QWIP focal plane. 相似文献
3.
Wing-Sum Cheung Patricia J.Y. Wong 《Journal of Mathematical Analysis and Applications》2007,329(2):851-869
We consider a system of focal boundary value problems where the nonlinearities may be singular in the independent variable and may also be singular in the dependent arguments. Using Schauder fixed point theorem, we establish criteria such that the system of boundary value problems has at least one fixed-sign solution. 相似文献
4.
对二维平面系统的二维系统的中心焦点区分问题 ,I l'yashenko曾建议一个算法 ,本文给出此法的详细证明 .据此 ,我们讨论了区分问题在 Arnold意义下的代数可解性与不可解性 相似文献
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基于厄米-双曲余弦高斯光束通过无光阑限制薄透镜聚焦的解析传输公式,研究了厄米-双曲余弦高斯光束聚焦区域的光强分布,并对光束的焦移进行了分析,讨论了偏心参数对光强主极大位置的影响。结果表明:TEM11模厄米-双曲余弦高斯光束的相对焦移(绝对值)随偏心参数和菲涅尔数的减小而增大,菲涅尔数较大时相对焦移趋于零。TEM22模光束在偏心参数小于0.54时,轴外与轴上光强极大值的比值大于1,此时光强主极大在轴外,偏心参数大于0.54时则相反;在偏心参数等于0.54时比值为1,此时光束有两个主极大,偏心参数愈大光强愈集中于轴上。使用LW法和GH法得到的TEM22模光束的相对焦移(绝对值)随偏心参数和菲涅尔数的变化规律与TEM11模光束一致,但相同参数下使用这两种方法得出的具体结果不同。 相似文献
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Vikram S. Deshpande Milan Mrksich Anthony G. Evans 《Journal of the mechanics and physics of solids》2008,56(4):1484-1510
Focal adhesions (FAs) are large, multi-protein complexes that provide a mechanical link between the cytoskeletal contractile machinery and the extracellular matrix. They exhibit mechanosensitive properties; they self-assemble upon application of pulling forces and dissociate when these forces are decreased. We rationalize this mechano-sensitivity from thermodynamic considerations and develop a continuum framework in which the cytoskeletal contractile forces generated by stress fibers drive the assembly of the FA multi-protein complexes. The FA model has three essential features: (i) the low and high affinity integrins co-exist in thermodynamic equilibrium, (ii) the low affinity integrins within the plasma membrane are mobile, and (iii) the contractile forces generated by the stress fibers are in mechanical equilibrium and change the free energies of the integrins. A general two-dimensional framework is presented and the essential features of the model illustrated using one-dimensional examples. Consistent with observations, the coupled stress fiber and FA model predict that (a) the FAs concentrate around the periphery of the cell; (b) the fraction of the cell covered by FAs increases with decreasing cell size while the total FA intensity increases with increasing cell size; and (c) the FA intensity decreases substantially when cell contractility is curtailed. 相似文献
9.
本文测定了新疆产新疆党参,新疆元胡等12种中草药中十种微量金属元素的含量.结果表明这些中草药中具有显著生理活性的Zn、Fe、Cu、Mn等元素.它们的含量除了个别样品外均大于或接近于国内其它地区所产的同种中草药、根据冠心病病因的Zn/Cu值假说和微量金属元素的含量关系,新疆产12种中草药也可用于防治冠心病. 相似文献
10.
Barnes JH Schilling GD Stone SF Sperline RP Denton MB Young ET Barinaga CJ Koppenaal DW Hieftje GM 《Analytical and bioanalytical chemistry》2004,380(2):227-234
The use of a separation step, such as liquid chromatography, prior to inductively coupled plasma mass spectrometry (ICP–MS) has become a common tool for highly selective and sensitive analyses. This type of coupling has several benefits including the ability to perform speciation analysis or to remove isobaric interferences. Several limitations of conventional instruments result from the necessity to scan or pulse the mass spectrometer to obtain a complete mass spectrum. When the instrument is operated in such a non-continuous manner, duty cycle is reduced, resulting in poorer absolute limits of detection. Additionally, with scanning instruments, spectral skew can be introduced into the measurement, limiting quantitation accuracy. To address these shortcomings, a high-performance liquid chromatograph has been coupled to an ICP–MS capable of continuous sample introduction and simultaneous multimass detection. These features have been realized with a novel detector array, the focal plane camera. Instrument performance has been tested for both speciation analysis and for the elimination of isobaric interferences. Absolute limits of detection in the sub picogram to tens of picograms regime are obtainable, while the added mass dimension introduced by simultaneous detection dramatically increases chromatographic peak capacity. 相似文献