Complementary electric-LC resonator antenna for WLAN applications

In this paper, a metamaterial antenna based on complementary electric-LC (CELC) resonator is proposed. The antenna consists of slot-loaded ELC on the ground plane as the main antennas radiating element and excited by a microstrip line. The CELC resonator is characterized by single-negative magnetic moment excited by coupling between the microstrip transmission line and slot-loaded CELC. The peak realized gain and efficiency of 2.63 dB and 86 % are obtained, respectively, at resonance frequency. Simulation and measurement results are presented to validate the design. The antenna is suitable for WLAN applications (2.39–2.48 GHz).     

Hydrothermal Synthesis,Crystal Structure,and Photoluminescent Properties of Li[UO2(CH3COO)3]3[Co(H2O)6]

Crystallography Reports - Single crystal of Li[UO2(CH3COO)3]3[Co(H2O)6] was prepared and found to crystallize in the monoclinic crystal system in the sp. gr. C2/c, with Z = 2, and unit cell...     

Synthesis,Crystal Structure and Thermodynamic Calculations of 1,3-Diethyl-5-(diethylaminium)methylene-2-thiobarbituric Acid Adduct

Abstract  

5-[(Diethylammonio)methyl]-1,3-diethyl-6-oxo-2-thioxo-1,2,3,6-tetrahydro-4-pyrimidinolate (3) was obtained in good yield from the reaction of 1,3-diethyl-6-oxo-5-(1-pyridiniumylmethyl)-2-thioxo-1,2,3,6-tetrahydro-4-pyrimidinolate (2) and diethylamine. The crystal structure of 3 and thermodynamic calculations pertaining to that structure are discussed. The obtained product was characterized using different techniques including single crystal X-ray diffraction, NMR spectroscopy and uni (bi)-molecular systems in gaseous phase. Compound 3 crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 13.3701(11) ?, b = 10.9983(7) ?, c = 20.8855(15) ?, β = 105.448(6)°, V = 2960.2(15) ?, Z = 8.     

Large scale behavior of wavelet coefficients of non-linear subordinated processes with long memory

We study the asymptotic behavior of wavelet coefficients of random processes with long memory. These processes may be stationary or not and are obtained as the output of non-linear filter with Gaussian input. The wavelet coefficients that appear in the limit are random, typically non-Gaussian and belong to a Wiener chaos. They can be interpreted as wavelet coefficients of a generalized self-similar process.     

A characterization of mixing processes of type G1

A stationary Gaussian process is mixing if and only if its covariance function tends to zero as the lag increases to infinity. We give an analogous characterization for a large class of symmetric infinitely divisible processes, known as processes of type G, whose marginal distribution are variance mixtures of the normal distribution.The first author is also associated with the Hugo Steinhaus Center for Stochastic Methods, Poland. The second author was partially supported by the ONR Grant N00014-90-J-1287 at Boston University and by a grant of the United States-Israel Binational Science Foundation.     

A Multiscale Theory of Swelling Porous Media: II. Dual Porosity Models for Consolidation of Clays Incorporating Physicochemical Effects

A three-scale theory of swelling clay soils is developed which incorporates physico-chemical effects and delayed adsorbed water flow during secondary consolidation. Following earlier work, at the microscale the clay platelets and adsorbed water (water between the platelets) are considered as distinct nonoverlaying continua. At the intermediate (meso) scale the clay platelets and the adsorbed water are homogenized in the spirit of hybrid mixture theory, so that, at the mesoscale they may be thought of as two overlaying continua, each having a well defined mass density. Within this framework the swelling pressure is defined thermodynamically and it is shown to govern the effect of physico-chemical forces in a modified Terzaghi's effective stress principle. A homogenization procedure is used to upscale the mesoscale mixture of clay particles and bulk water (water next to the swelling mesoscale particles) to the macroscale. The resultant model is of dual porosity type where the clay particles act as sources/sinks of water to the macroscale bulk phase flow. The dual porosity model can be reduced to a single porosity model with long term memory by using Green's functions. The resultant theory provides a rational basis for some viscoelastic models of secondary consolidation.     

A Two-Scale Model for Coupled Electro-Chemo-Mechanical Phenomena and Onsager’s Reciprocity Relations in Expansive Clays: I Homogenization Analysis

The macroscopic model governing coupled electro-chemo-mechanical phenomena in expansive clays is revisited within a rigorous homogenization procedure applied to the microscopic governing equations which describe the local interaction between charged clay particles and a binary monovalent aqueous electrolyte solution. The up-scaling of the microscopic electro-hydro-dynamics leads to a two-scale approach wherein the macroscopic model appears governed by a fully coupled form of Onsager’s reciprocity relations, mass conservation equations and a modified Terzaghi’s effective stress principle. In addition, the two-scale approach provides microscopic representations for the effective coefficients which are exploited herein to obtain further insight in the constitutive behavior of the electrochemical parameters and the swelling pressure. Among other effects, we show that these microscopic closure relations are mainly dictated by the spatial variability of a microscale electric potential which satisfies a local version of the Poisson–Boltzmann problem in a periodic unit cell, The proposed framework allows to address various relevant still open issues regarding the constitutive behavior of swelling systems, Among them we give particular emphasis on the analysis of the influence of the fluctuation and distortion of the electrical double layer upon the magnitude of the electrochemical coefficients and the precise local conditions for the validity of the symmetry of Onsager’s relations.     

The Universality of Homogeneous Polynomial Forms and Critical Limits

Nourdin et al. (Ann Probab 38(5):1947–1985, 2010) established the following universality result: if a sequence of off-diagonal homogeneous polynomial forms in i.i.d. standard normal random variables converges in distribution to a normal, then the convergence also holds if one replaces these i.i.d. standard normal random variables in the polynomial forms by any independent standardized random variables with uniformly bounded third absolute moment. The result, which was stated for polynomial forms with a finite number of terms, can be extended to allow an infinite number of terms in the polynomial forms. Based on a contraction criterion derived from this extended universality result, we prove a central limit theorem for a strongly dependent nonlinear process whose memory parameter lies at the boundary between short and long memory.