Rayleigh wave scattering due to a rigid barrier in a liquid halfspace

The paper presents a theoretical formulation for studying scattering of Rayleigh waves due to the presence of rigid barriers in oceanic waters. The Wiener-Hopf technique has been employed to solve the problem. Exact solution has been obtained in terms of Fourier integrals whose evaluation gives the reflected, transmitted and scattered waves. The scattered waves have the behaviour of cylindrical waves originating at the edge of the barrier. Numerical results for the amplitude of the scattered waves have been obtained for small depth of the barrier.     

Excess Volume of Mixing of 1:1 Electrolyte Solutions at 298.15 K in the Aquo-1,4-Dioxane Mixed-Solvent System

Excess volumes of mixing for six possible binary combinations of solutions of NaCl, KCl, NaBr and KBr have been determined at constant ionic strengths of 1.000 and 2.000 mol-kg^{− 1} at 298.15 K using a dilatometer in the water + 1,4-dioxane mixed-solvent system. Pitzer’s ion-interaction model has been utilized to obtain binary and triplet interaction parameters, i.e., θ^V and ψ^V. The data were also analyzed by the Friedman Model and it is suggested that interactions between solvated ions are dictated not only by coulombic interactions but also by appreciable asymmetric effects. The data are dependent on the nature of the common ion and do not support Young’s cross-square rule. The deviation from the cross-square rule is considered to arise from preferential solvation of the ions and ion clusters in the mixed-solvent system as reflected by the appreciable contribution of triplet interactions.     

Scattering of Love waves due to the presence of a rigid barrier of finite depth in the crustal layer of the earth

The problem of scattering of Love waves due to the presence of a rigid barrier of finite depth in the crusfal layer of the earth is studied in the present paper. The barrier is in the slightly dissipative surface layer and the surface of the layer is a free surface. The Wiener-Hopf technique is the method of solution. Evaluation of the integrals along appropriate contours in the complex plane yields the reflected, transmitted and the scattered waves. The scattered waves behave as a decaying cylindrical wave at distant points. Numrical computations for the amplitude of the scattered waves have been made versus the wave number. The amplitude falls off rapidly as the wave number increases very slowly.     

Rayleigh wave scattering by a plane strip in a deep ocean

A theoretical formulation to study the problem of scattering of Rayleigh waves due to the presence of a rigid plane strip in a deep ocean is presented. A rigid plane strip (0 ≤z ≤ H, 0 ≤x ≤ l) is fixed in the surface of the ocean occupyingz ≥ 0. Fourier transformation and Wiener-Hopf technique are used to arrive at the solution. The scattered Rayleigh waves behave as cylindrical waves emerging out of the corner of the strip and its image in the free surface of the ocean. The scattered waves are obtained in terms of Bessel functions whose behaviour near and far from the strip is well-known. The numerical calculations for the scattered waves show that their amplitude increases rapidly for a small increase in the value of the wave number. Scattering of Rayleigh waves due to a thin plane vertical barrier and a thin barrier in the free surface of the ocean has been considered as the special cases.     

Thermodynamics of 1:1 Electrolyte Solutions in Water + N,N-Dimethylformamide Mixed Solvent System at 25°C: Molar Excess Enthalpy of Mixing

The molar excess enthalpies of mixing for the six possible binary combinationsof solutions of NaCl, KCl, NaBr, and KBr as a function of ionic strength fractionhave been measured at 25°C. The experiments were performed at constant ionicstrengths of 1.000 and 2.000 mol-kg^–1 with an LKB flow microcalorimeter inthe mixed solvent water + dimethylformamide. The equations of Friedman'sModel were fitted to the results. Our parameters differ appreciably from thecorresponding results in water and Young's cross square rule does not apply.While Pitzer's ion-interaction model was able to represent the enthalpy data forcommon ion mixings, it was unable to model the data of the noncommon ionmixtures. The data suggests that the problem may arise from variations in solvationof the ions and ion clusters including preferential solvation of certain species.