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931.
We theoretically investigate plasmonic properties of a calcium film in a Kretschmann excitation scheme. Based on surface plasmon polaritons, the absorbance of the calcium film can be as high as 100% for the p-polarization, much higher than the absorbance for the s-polarization at the wavelength of 422.7 nm, correspondingly to the g Fraunhofer line. The 45 nm thick film of calcium has a high reflectance of about 76% at 422.7 nm for s-polarization. But for p-polarization, there is a minimum in the reflectivity curves at the angle of 19°. The narrow-band filter based on calcium film is particularly suited for working with conventional calcium atomic filter and on-chip integration due to its solid-state bulky feature. Furthermore, the plasmonic filter based on the calcium film is described that may offers new applications in angle- and polarization-sensitive sensor and the detection of weak laser light. 相似文献
932.
For multimode pulsed dye lasers (of nanosecond and microsecond duration with frequency-dependent losses in the cavity), experimental
studies and theoretical calculations have been made of the dependence of the value of the equivalent line width, used as a
measure of selective absorption, on the main parameters characterizing the laser, the cavity, and the absorbent. Analytical
relations have been obtained which describe the main aspects of complete absorption in lines with dispersion, Gaussian, or
mixed spectra profiles, and their experimental testing has been carried out.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 327–332, May–June, 2000. 相似文献
933.
Optimizing glass coating lines: MIP model and valid inequalities 总被引:1,自引:0,他引:1
C. Gicquel N. Migeville M. Minoux Y. Dallery 《European Journal of Operational Research》2010,202(3):747-755
Glass coating is a specific transformation aiming at improving glass performance. The work presented in this paper deals with the determination of the optimal configuration of the production lines used to perform this operation. We propose a first MIP formulation of the problem and then discuss several types of valid inequalities for improving it. The main idea is to exploit explicit or implicit binary exclusion constraints to derive stronger valid inequalities: the maximal clique constraints. Efficient (polynomial time) separation algorithms exploiting special structure of the problem are described, giving rise to a cutting-plane generation procedure for strengthening the initial formulation. The computational study carried out shows that, with the enhanced formulation, good solutions can be obtained within reasonable computation times using currently available integer programming software. 相似文献
934.
The influence of topography on dynamic wetting 总被引:1,自引:0,他引:1
The paramount importance of wetting applications and the significant economic value of controlling wetting-based industrial processes has stimulated a deep interest in wetting science. In many industrial applications the motion of a complex liquid front over nano-textured surfaces controls the fate of the processes. However our knowledge of the impact of nano-heterogeneities on static and dynamic wetting is very limited. In this article, the fundamentals of wetting are briefly reviewed, with a particular focus on hysteresis and roughness issues. Present knowledge and models of dynamic wetting on smooth and rough surfaces are then examined, with particular attention devoted to the case of nano-topographical heterogeneities and solid–fluid–fluid systems. 相似文献
935.
Using data present in the literature from wind tunnel testing of semi-infinite and infinite rectangular bluff bodies at angle of attack, we develop a simple relation to predict the range of angles of attack where the lift remains approximately constant. This prediction is useful for researchers attempting to develop simplified models of the forces on rectangular bluff bodies. Additionally, prior work has shown that this region of the lift curve is characterized by complex three-dimensional flow, which has consequences for computational simulations. 相似文献
936.
Through the analyses on the irreversibility lines (ILLs) under H||c for various high-Tc superconducting (HTSC) single-crystalline samples, we found two universal functions representing ILLs. In these functions, the electromagnetic anisotropy factor γ2 plays a crucial role. The appropriate chemical substitution, such as Bi(Pb)2212, is an effective method to improve flux pinning properties via decreasing γ2. 相似文献
937.
G. Yeandle J. Billowes P. Campbell P. Dendooven K. Peräjärvi M.D. Seliverstov G. Tungate J. Äystö 《Hyperfine Interactions》2000,127(1-4):91-94
The method of resonance ionization spectroscopy for measurements of hyperfine structures and isotope shifts of heavy elements, at the IGISOL facility, Jyväskylä, is discussed. Two laser geometries are considered, with reference to the effect they have on resolution and efficiency of measurements. Results of off line resonance ionization tests on natural sodium are reported. 相似文献
938.
D. Bratkowska R.M. Marcé P.A.G. Cormack D.C. Sherrington F. Borrull N. Fontanals 《Journal of chromatography. A》2010,1217(10):1575-1582
The synthesis of high specific surface area sorbents (HXLPP-WCX) in the form of hypercrosslinked polymer microspheres with narrow particle size distributions, average particle diameters around 6 μm, and weak cation-exchange (WCX) character, is described. The WCX character arises from carboxylic acid moieties in the polymers, derived from the comonomer methacrylic acid. A novel HXLPP-WCX sorbent with an attractive set of chemical and physical properties was then used in an off-line solid-phase extraction (SPE) protocol for the selective extraction of a group of basic compounds from complex environmental samples, a priority being the clean separation of the basic compounds of interest from acidic compounds and interferences. The separation power of the new sorbent for basic pharmaceuticals was compared to two commercially available, mixed-mode sorbents, namely Oasis WCX and Strata-X-CW. Under identical experimental conditions, HXLPP-WCX was found to deliver both higher capacity and better selectivity in SPE than either of the two commercially available materials. In an optimised SPE protocol, the HXLPP-WCX sorbent gave rise to quantitative and selective extractions of low μg l−1 levels of basic pharmaceuticals present in 500 ml of river water and 250 ml of effluent waste water. 相似文献
939.
Finner et al. (2012) provided multiple hypothesis testing procedures based on a nonlinear rejection curve for exact false discovery rate control. This paper constructs classes of such procedures and compares the most powerful procedure in each class to competing procedures. 相似文献
940.
A finite difference beam propagation algorithm based on generalized transmission line equations 总被引:3,自引:0,他引:3
A wide angle beam propagation algorithm is presented, which is based on generalized transmission line (GTL) equations. Besides the discretization, no further approximation is introduced. In principle, a full vectorial analysis is possible, and anisotropic material can be taken into account. The algorithm has been verified for planar 2D-waveguide devices. The wide angle characteristic has been examined by determining the propagation of tilted Gaussian beams in homogeneous media. Further studies were performed for tilted waveguides and for taper structures. Results for the latter devices were compared with other methods showing a very good agreement. 相似文献