Application of particle swarm optimization in chaos synchronization in noisy environment in presence of unknown parameter uncertainty

In this paper, particle swarm optimization (PSO) is applied to synchronize chaotic systems in presence of parameter uncertainties and measurement noise. Particle swarm optimization is an evolutionary algorithm which is introduced by Kennedy and Eberhart. This algorithm is inspired by birds flocking. Optimization algorithms can be applied to control by defining an appropriate cost function that guarantees stability of system. In presence of environment noise and parameter uncertainty, robustness plays a crucial role in succeed of controller. Since PSO needs only rudimentary information about the system, it can be a suitable algorithm for this case. Simulation results confirm that the proposed controller can handle the uncertainty and environment noise without any extra information about them. A comparison with some earlier works is performed during simulations.     

Cavity enhancement of the magneto-optic Kerr effect in glass/Al/SnO2/PtMnSb/SnO2 structure

The cavity enhancement effect of the transparent semiconductor SnO₂ on the magneto-optical Kerr response of the glass/Al/SnO₂/PtMnSb/SnO₂ multilayer structure has been investigated using a matrix method. It has been demonstrated that device optimization leads to large Kerr rotation and figure of merit (FOM) with a vanishing ellipticity in the visible portion of the electromagnetic spectrum, especially at short wavelengths. This optimization is of interest in view of optical data storage technology. Using numerical simulations, we have also shown that in the optimum condition, the device readout parameters behave smoothly against the design variables.     

Heat transfer and Couette flow of a chemically reacting non‐linear fluid

In this paper we study the flow and heat transfer in a chemically reacting non‐linear fluid between two long horizontal parallel flat plates that are at different temperatures. The top plate is sheared, whereas the bottom plate is fixed. The fluid is modeled as a generalized power‐law fluid whose viscosity is also assumed to be a function of the concentration. The effects of radiation are neglected. The equations are made dimensionless and the boundary value problem is solved numerically; the velocity and temperature profiles are obtained for various dimensionless numbers. Published in 2009 by John Wiley & Sons, Ltd.     

Simple and sensitive high-performance liquid chromatography method for the quantitation of indinavir in rat plasma and central nervous system

A simple and sensitive RP-HPLC method using UV detection (215 nm) was developed for the determination of indinavir concentrations in rat plasma, cerebrospinal fluid (CSF), and brain tissue homogenates. Biological samples were processed using a combination of acid pretreatment and liquid-liquid extraction with verapamil used as the internal standard. This method produced a linear response throughout the indinavir concentration range of 0.05-30 microM in plasma and 0.05-2.5 microM in CSF and brain with a LOD of 12.5 nM for plasma and CSF, and 6.25 nM for brain homogenate. Due to its high sensitivity, this assay is particularly useful for the quantitative determination of indinavir concentrations in brain and CSF.     

On the use of lattice Boltzmann model for simulating dean flow of non-Newtonian fluids in curved square ducts

In the present work, the effect of a fluid’s shear-thinning and extension-hardening behavior is investigated on its flow characteristics in a typical curved square duct using a three-dimensional 27-velocities (D3Q27) incompressible lattice Boltzmann model. The main objective of the work is to examine how a fluid’s non-Newtonian viscous behavior affects the onset of Dean instability (i.e., the sudden shift from a two-cell to a four-cell vortex structure) in a curved square duct. The fluid of interest is assumed to obey Pinho’s rheological model in which shear-thinning and extension-hardening are both represented by a single power-law equation. It is found that shear-thinning has a stabilizing effect on the flow. On the other hand, extension-hardening is found to destabilize the flow.     

Preparation of chromium and sulfur single and co-doped TiO2 nanostructures for efficient photoelectrochemical water splitting: effect of aliphatic alcohols on their activity

Journal of Solid State Electrochemistry - Single and co-doped chromium and sulfur TiO2 nanotubes appropriate for photoelectrochemical water splitting application have been prepared and...     

A structural interpretation of the two components governing the kinetic fragility from the example of interpenetrated polymer networks

Kinetic fragility and cooperativity length, two major characteristics of the relaxation dynamics at the glass transition, are, respectively, investigated by dynamic mechanical analysis and modulated temperature differential scanning calorimetry in a series of interpenetrated polymer networks based on acrylate and epoxy systems. The relaxation dynamics are impacted by two variables: the rigidity of the network, and the structural heterogeneity resulting from blending. However, the fragility and the cooperativity do not vary similarly. The glass transition progressively broadens as the mass fractions of acrylate and epoxy become equivalent, leading to a strong decrease in cooperativity. On the other hand, under the same conditions, the fragility transitions between the lower value of pure acrylate and the higher value of pure epoxy. This divergence helps concluding that the variations in the temperature dependence of the relaxation time are not purely related to the more or less cooperative nature of the glass transition. By splitting the fragility index in a volume contribution and an energetic contribution, it is shown that the contribution of cooperativity to the variations of the relaxation time with temperature is increased under two structural conditions: low backbone rigidity and high intermolecular interactions. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1393–1403     

C*-simplicity and the unique trace property for discrete groups

A discrete group is said to be C*-simple if its reduced C*-algebra is simple, and is said to have the unique trace property if its reduced C*-algebra has a unique tracial state. A dynamical characterization of C*-simplicity was recently obtained by the second and third named authors. In this paper, we introduce new methods for working with group and crossed product C*-algebras that allow us to take the study of C*-simplicity a step further, and in addition to settle the longstanding open problem of characterizing groups with the unique trace property. We give a new and self-contained proof of the aforementioned characterization of C*-simplicity. This yields a new characterization of C*-simplicity in terms of the weak containment of quasi-regular representations. We introduce a convenient algebraic condition that implies C*-simplicity, and show that this condition is satisfied by a vast class of groups, encompassing virtually all previously known examples as well as many new ones. We also settle a question of Skandalis and de la Harpe on the simplicity of reduced crossed products. Finally, we introduce a new property for discrete groups that is closely related to C*-simplicity, and use it to prove a broad generalization of a theorem of Zimmer, originally conjectured by Connes and Sullivan, about amenable actions.     

Different molecular assemblies in two new phosphoric triamides with the same C(O)NHP(O)(NH)<Subscript>2</Subscript> skeleton: crystallographic study and Hirshfeld surface analysis

Different molecular assemblies were compared in two new structures [4-CH₃-C₆H₄C(O)NH]P(O)[NH]₂(CH₂)₃, 1, and [4-CH₃-C₆H₄C(O)NH]P(O)[NHC₆H₃(3,4-CH₃)₂]₂, 2, belonging to the families of “cyclic phosphoric triamide” and “phosphoric triamide”, respectively. The differences in the hydrogen bond motifs were discussed (by single crystal X-ray diffraction) as a result of three factors: (1) action of two N atoms with a non-planar environment in 1 as an H-bond acceptor, (2) different orientations of three N–H bond vectors in two molecules and (3) different conformations of C=O and P=O groups. These differences lead to more complicated hydrogen bond pattern of 1, with respect to that of 2, as structure 1 may be considered as a model of four-acceptor–three-donor versus a two-acceptor–three-donor system in 2. The main discrepancies of 1 and 2, monitored by the Hirshfeld surface analysis, are related to the contribution portions of O···H/H···O contacts, in which compound 1 not only involves the greater existence of classical hydrogen bonds but also contains the further C–H···O weak interactions in its crystal packing with respect to compound 2. Instead, in 2, the shortage of O···H/H···O contacts has been partially compensated by the C···H/H···C interactions, due to the presence of more unsaturated carbon acceptors. The differences in assemblies are also reflected in the solid-state IR spectra, especially for the N–H vibration frequencies. The new compounds were further studied by 1D NMR experiments (¹H, ¹³C, ³¹P), 2D NMR techniques [HMQC and HMBC (H–C correlation), HSQC (N–H correlation)], high-resolution ESI–MS, EI–MS spectrometry and IR spectroscopy.