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Periodic Arrangement (periodic + arrangement)
Selected AbstractsSynthesis of Light-Diffracting Assemblies from Microspheres and Nanoparticles in Droplets on a Superhydrophobic Surface,ADVANCED MATERIALS, Issue 22 2008Vinayak Rastogi Aqueous suspension droplets of monodisperse latex or latex and gold nanoparticles mixtures assume spherical shape on superhydrophobic substrates. The drying sessile droplets serve as macroscopic templates for assembling microspheres into closed-packed structures. Upon illumination, the supraparticles display discrete colored rings because of the periodic arrangement of latex particles in the surface layer. The physical origin of the colored patterns is explained in detail. [source] Novel effects in finite-length silicon nanowiresPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 11 2008A. D. Zdetsis Abstract By considering silicon nanowires in real space, we have shown by ab initio theoretical calculations that unstable nanowires bend under relaxation. These nanowires usually incorporate in their surface silicon dihydrides parallel to the nanowires axis. On the other hand, nanowires without such parallel dihydrides remain straight and are characterized by increased stability or "magicity". Reconstructed nanowires have analogous properties but they are characterized by much higher stability. This bending of the nanowires cannot be accounted for by the usual k-space models which use a one-dimensional periodic arrangement of the simulation cell. Our theoretical models are based on STM images and schematic views from recent experimental results [Science 229, 1874, (2003)]. Our results are in full accord with these experimental data and interpretations. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Transmission, refraction, and focusing properties of labyrinth based left-handed metamaterialsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 4 2007Ekmel Özbay Abstract In this present article, we studied the transmission, refraction and focusing properties of one, two and three dimensional labyrinth based left-handed metamaterials. We demonstrated that the proper periodic arrangement of labyrinth structures and wires results in left-handed transmission. By using a two dimensional labyrinth based left-handed slab, it is shown that it is possible to image the field emitted from source in sub-wavelength detail. Moreover, we demonstrated the focusing and negative refraction of electromagnetic waves by a three dimensional labyrinth based left-handed slab. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Deterministic self-organization: Ordered positioning of InAs quantum dots by self-organized anisotropic strain engineering on patterned GaAs (311)BPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2009E. Selçuk Abstract Laterally ordered InGaAs quantum dot (QD) arrays, InAs QD molecules, and single InAs QDs in a spot-like periodic arrangement are created by self-organized anisotropic strain engineering of InGaAs/GaAs superlattice (SL) templates on planar GaAs (311)B substrates in molecular beam epitaxy. On shallow- and deep-patterned substrates the respectively generated steps and facets guide the self-organization process during SL template formation to create more complex ordering such as periodic stripes, depending on pattern design. Here we demonstrate for patterns such as shallow- and deepetched round holes and deep-etched zigzag mesas that the self-organized periodic arrangement of QD molecules and single QDs is spatially locked to the pattern sidewalls and corners. This extends the concept of guided self-organization to deterministic self-organization. Absolute position control of the QDs is achieved without one-to-one pattern definition. This guarantees the excellent arrangement control of the ordered QD molecules and single QDs with strong photoluminescence emission up to room temperature, which is required for future quantum functional devices. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Viscous flow in three-dimensional reconstructed porous mediaINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 8 2003Marco Pilotti Abstract In a recent paper Masad et al. (Int. J. Numer. Methods Eng. 2000; 26: 53,74) have shown the possibility of numerically studying fluid flow within two-dimensional microscopic images of granular materials. In this paper we investigate the possibility of computing the flow field at the pore scale within numerically reconstructed three dimensional porous media, by coupling a physically based sedimentation algorithm for porous media generation and a Lattice Boltzmann Technique for solving Navier equations for the monophasic flow of a newtonian fluid inside the intergranular space. Since the adopted sedimentation algorithm can produce porous media with a controlled level of complexity, we believe that this type of approach provides an ideal numerical laboratory to probe the effect of void space topology and geometry on the flow field. This should allow to understand the fluid-dynamic implications of processes such as compaction and cementation. After showing that the Lattice Boltzmann Technique is effective in solving Navier equations in porous media also at moderately high Reynolds, where Darcy's flow does not strictly hold anymore, we investigate the distribution of velocity components within porous media of growing complexity, starting from two different periodic arrangements of spheres up to a mixture of log-normally distributed spheres. We observe that the distribution of velocity components is conditioned by the medium complexity and tends to an exponential pattern. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||