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排序方式: 共有343条查询结果,搜索用时 903 毫秒
291.
Mihail Enachi Oleg Lupan Tudor Braniste Andrei Sarua Lee Chow Yogendra K. Mishra Dawit Gedamu Rainer Adelung Ion Tiginyanu 《固体物理学:研究快报》2015,9(3):171-174
Titania (TiO2) exists in several phases possessing different physical properties. In view of this fact, we report on three types of hydrogen sensors based on individual TiO2 nanotubes (NTs) with three different structures consisting of amorphous, anatase or anatase/rutile mixed phases. Different phases of the NTs were produced by controlling the temperature of post‐anodization thermal treatment. Integration of individual TiO2 nanotubes on the chip was performed by employing metal deposition function in the focused ion beam (FIB/SEM) instrument. Gas response was studied for devices made from an as‐grown individual nanotube with an amorphous structure, as well as from thermally annealed individual nanotubes exhibiting anatase crystalline phase or anatase/rutile heterogeneous structure. Based on electrical measurements using two Pt complex contacts deposited on a single TiO2 nanotube, we show that an individual NT with an anatase/rutile crystal structure annealed at 650 °C has a higher gas response to hydrogen at room temperature than samples annealed at 450 °C and as‐grown. The obtained results demonstrate that the structural properties of the TiO2 NTs make them a viable new gas sensing nanomaterial at room temperature. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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This paper presents the large deviation principle for stochastic evolution equation driven by gaussian martingales taking values in duals of nuclear Frechet spaces 相似文献
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Tiberiu Tudor 《Optik》2010,121(13):1226-1235
This paper inscribes on the line of the efforts (sketched in the Introduction) in elaborating theoretical approaches alternative to the traditional Jones and Mueller matrix calculi in polarization optics. The more abstract, compact and elevated forms of linear algebra are not fully exploited yet in the polarization optics. A vectorial and pure operatorial Pauli algebraic approach to the interaction between the polarized light and the polarization optical systems is given. This is the most compact, adequate and elegant calculus corresponding to the well-known geometric handling of the polarization states and their interaction with the polarization devices on the Poincaré sphere. In this first paper, we deduce the Pauli algebraic vectorial forms of the operators corresponding to the orthogonal and nonorthogonal polarization devices and to all the states of light polarization. In the next paper we shall give the vectorial Pauli algebraic analysis of the interaction between the whole hierarchy of these devices and the various forms of polarized light. 相似文献
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We investigate the statistical properties of two single-mode dye-laser models-the colored-loss-noise model and the colored-gain-noise model. Analytic expressions of the probability,the mean and the variance of the steady-state laser intensity are obtained through the unified expansion theory [Phys. Rev. A43 (1991) 700]. By comparison we find that when the cavity decay rate for the electric field is large and the pump parameter a0 is small, the differences of the results of the two laser models are small. Otherwise, the differences are large. And the correlation time of the noise has very obvious influence on the results of the two models. 相似文献
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当网络上(诸如交通网络、通讯网络)有多种不同物资或信息同时分别从相应的发点输送到相应的收点,要求每条线路上各类物资或信息的输送量总和不超过线路的容量时,寻求所有物资的最大输送量的问题,就是所谓网络多种物资的最大流问题,这个问题在生产实际和理论上都有着重要的意义,1963年T.C.Hu提出了求两类物资联合最大流的标号方法,但是为了保证有限步达到最大流,要求边的容量是偶数。 本文是文献[3]的继续,用图论的语言描述了两类物资最大流问题极流的特征,并对标号方法作了一点修改,使得有限步得到最大流,或者在某一步得到极流后,保证以后的迭代是从极流到极流.这样因极流的个数是有限的,并且最大流总可以在极流上达到,从而保证了有限步内得到所要求的最大流,无须对边的容量作任何限制, 本文所提的算法是使图形特征很强的标号算法和线性规划的极点迭代结合起来,这就使得有可能把这种方法,推广到更大的一类问题中,例如,研究容量的改变对最大流量的影响。 相似文献
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Partially supported by NSF grant DMS89-96210 相似文献
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