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91.
We describe a wave-front displacement system using a novel configuration of a pair of wedge prisms. The wave-front propagation, through the displacement system, is analyzed using the exact ray trace. The main advantage, of this configuration, is that the shearing (direction and magnitude) is constant from the displacement system to the image plane. The direction of the shearing depends on the relative orientation of the prisms. The magnitude of the shearing is proportional to the distance between prisms. The proportionality constant depends on the wedge angle and the material of fabrication of the prisms, and it gives the sensitivity to the displacement of the system. The deviation of the shearing due to the difference between the wedge angles is larger than that the produced by the oblique incidence of the wave-front. The experimental results confirm the theoretical data. 相似文献
92.
Slobodan M. Vuković Zoran Jakšić Ilya V. Shadrivov Yuri S. Kivshar 《Applied Physics A: Materials Science & Processing》2011,103(3):615-617
We study the properties of electromagnetic waves propagating along the waveguides with a periodic core created by alternating
metal and dielectric layers, the so-called quasi-one-dimensional plasmonic crystal waveguides. Such waveguides can be symmetric
or asymmetric, depending on the cladding or substrate material properties, as well as on the termination of the periodic structure.
We analyze the dispersion characteristics as well as the profiles of the guided modes for several types of waveguide structure. 相似文献
93.
Marija P. Stanić Aleksandar S. Cvetković Tatjana V. Tomović 《Mathematical Methods in the Applied Sciences》2014,37(11):1687-1699
In this paper, we give error estimates for quadrature rules with maximal trigonometric degree of exactness with respect to an even weight function on ( ? π,π) for integrand analytic in a certain domain of complex plane. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
94.
95.
In this paper, we propose a novel preconditioned solver for generalized Hermitian eigenvalue problems. More specifically, we address the case of a definite matrix pencil \(A-\lambda B\) , that is, A, B are Hermitian and there is a shift \(\lambda _{0}\) such that \(A-\lambda _{0} B\) is definite. Our new method can be seen as a variant of the popular LOBPCG method operating in an indefinite inner product. It also turns out to be a generalization of the recently proposed LOBP4DCG method by Bai and Li for solving product eigenvalue problems. Several numerical experiments demonstrate the effectiveness of our method for addressing certain product and quadratic eigenvalue problems. 相似文献
96.
Marija S. Nikolic Dr. Charlotta Olsson Andrea Salcher Andreas Kornowski Anja Rank Dr. Rolf Schubert Prof. Dr. Andreas Frömsdorf Dr. Horst Weller Prof. Dr. Stephan Förster Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(15):2752-2754
Nanoparticle brushes : Complex nanostructures can be formed by self assembly of amphiphilic CdSe/CdS core–shell nanoparticles that bear a brushlike layer of poly(ethylene oxide) chains. This route is based on controlling the volume fractions of hydrophilic and hydrophobic moieties within the particles and allows the formation of micellar, cylindrical, or vesicular nanoobjects (see picture).
97.
Horvat Alka J. M. Živko-Babić Jasenka Ivanković Danijela Babić Sandra Kaštelan-Macan Marija 《平面色谱法杂志一现代薄层色谱法》2001,14(6):426-429
JPC – Journal of Planar Chromatography – Modern TLC - Knowledge of the composition of an incorporated alloy is a precondition for avoiding polymetallism in subsequent prosthetic... 相似文献
98.
Structure and dynamics of highly PEG-ylated sterically stabilized micelles in aqueous media 总被引:1,自引:0,他引:1
Vuković L Khatib FA Drake SP Madriaga A Brandenburg KS Král P Onyuksel H 《Journal of the American Chemical Society》2011,133(34):13481-13488
Molecular assemblies of highly PEG-ylated phospholipids are important in many biomedical applications. We have studied sterically stabilized micelles (SSMs) of self-assembled DSPE–PEG2000 in pure water and isotonic HEPES-buffered saline solution. The observed SSM sizes of 2–15 nm largely depend on the solvent and the lipid concentration used. The critical micelle concentration of DSPE–PEG2000 is 10 times higher in water than in buffer, and the viscosity of the dispersion dramatically increases with the lipid concentration. To explain the experimentally observed results, we performed atomistic molecular dynamics simulations of solvated SSMs. Our modeling revealed that the observed assemblies have very different aggregation numbers (N(agg) ≈ 90 in saline solution and N(agg) < 8 in water) because of very different screening of their charged PO4(–) groups. We also demonstrate that the micelle cores can inflate and their coronas can fluctuate strongly, thus allowing storage and delivery of molecules with different chemistries. 相似文献
99.
Central European Journal of Operations Research - Industry 4.0 (I4.0) implies a group of technologies, organisational concepts and management principles to improve the performance of manufacturing... 相似文献
100.