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151.
Teruyuki Yorioka 《Mathematical Logic Quarterly》2006,52(2):203-216
We prove the iteration lemmata, which are the key lemmata to show that extensions by Pmax variations satisfy absoluteness for Π2-statements in the structure 〈H (ω 2), ∈, NSω 1, R 〉 for some set R of reals in L (ℝ), for the following statements: (1) The cofinality of the null ideal is ℵ1. (2) There exists a good basis of the strong measure zero ideal. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
152.
153.
Chenghang Wang 《Applied Surface Science》2006,253(4):2282-2288
In this paper, thin films of titanium oxide imprinted with O,O-dimethyl-(2,4-dichlorophenoxyacetoxyl)(3′-nitrobenyl) methinephosphonate (Phi-NO2) were prepared via liquid phase deposition (LPD) method on a glassy carbon electrode. The imprinted molecular in the films was removed by treatment with immersion in CH2Cl2. X-ray diffraction (XRD) and electrochemical methods were introduced to show the evidence of the molecular imprinting phenomenon. It was also found that the recognition ability of the sensor depended on the substituents associated with tridimensional structures of the nitro-compounds. Under the optimized condition, the sensor showed better sensitivity, selectivity and reproducibility to the imprinted molecule and the linear relationship between the current and the concentration of analyte in the range of 0.1-50 μM was obtained. LPD proved to be a powerful method for imprinting titanium oxide thin sense films. 相似文献
154.
Tadao Nozawa Fumio MorimotoRikio Harazono Norimoto Nouchi 《Journal of magnetism and magnetic materials》2006
Evaporative deposition at oblique incidence is shown to enhance the magnetic anisotropy of an Fe20Ni80 magnetic film and induce magnetic anisotropy in an overlying, strongly isotropic Fe70Co30 film. This deposition method for the formation of an underlayer of several lattice parameters in thickness and semi-hard overlayer of a few thousands Angstroms in thickness achieves a significant change in the magnetization process and strong suppression of the coercive forces of Fe70Co30 in the hard magnetization direction. Soft magnetization of the Fe70Co30 overlayer is not achieved when one of the layers is deposited at oblique incidence. It is anticipated that shape magnetic anisotropy is responsible in part for the magnetic anisotropy induced in both in Fe20Ni80 under- and Fe70Co30 overlayer by oblique incidence evaporation. 相似文献
155.
Highly ordered composite nanowires with multilayer Ni/Cu and NiFe/Cu have been fabricated by pulsed electrodeposition into
nanoporous alumina membrane. The diameter of wires can be easily varied by pore size of alumina, ranging from 30 to 100 nm.
The applied potential and the duration of each potential square pulse determine the thickness of the metal layers. The nanowires
have been characterized by transmission electron microscopy (TEM), magnetic force microscopy (MFM), and vibrating sample magnetometer
(VSM) measurements. The MFM images indicate that every ferromagnetic layer separated by Cu layer was present as single isolated
domain-like magnet. This technique has potential use in the measurement and application of magnetic nanodevices. 相似文献
156.
微纳米加工技术及其应用综述 总被引:2,自引:0,他引:2
材料与结构在微纳米尺度展现了许多不同于宏观尺度的新特征,纳米技术已经成为当前科学研究与工业开发的热门领域之一。微小型化依赖于微纳米尺度的功能结构与器件,实现功能结构微纳米化的基础是先进的微纳米加上技术,文章对微纳米加上技术做了一个综合的介绍,简要说明了微纳米加工技术与传统加工技术的区别,在微纳米加工技术的应用方面提出了一些合理选择加工技术的原则,并对当前微纳米加工技术面临的挑战和今后发展的趋势作了预测。 相似文献
157.
Karl Sigman 《Operations Research Letters》2007,35(5):581-583
In Mandelbaum and Yechiali [The conditional residual service time in the M/G/1 queue, http://www.math.tau.ac.il/∼uriy/publications (No. 30a), 1979] and in Fakinos [The expected remaining service time in a single-server queue, Oper. Res. 30 (1982) 1014-1018] a simple formula is derived for the (stationary) expected remaining service time in a M/G/1 queue, conditional on the number of customers in the system. We give a short new proof of the formula using Rate Conservation Law, and generalize to handle higher moments. 相似文献
158.
We study theoretically a nonlinear response of the planar metal/dielectric nanostructures constituted from periodical array
of ultra thin silver layers and the layers of Kerr-like nonlinear dielectric. We predict hysteresis-type dependences of the
components of the tensor of effective dielectric permittivity on the field intensity allowing the change in material transmission
properties from transparent to opaque and back at extremely low intensities of the light. It makes possible to control the
light by light in all-optical nanoscale devices and circuits. 相似文献
159.
160.
In the present paper, we consider the problem of the optimal reconstruction of the solution of the wave equation from the approximate values of the Fourier coefficients of the function specifying the initial form of the string. For an operator defined on the weight space of vectors from l 2, we present the solution of the more general problem of reconstruction from the approximate values of the coordinates of these vectors. 相似文献