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A set of single domain particles has been studied through Monte Carlo simulations on three different lattices. A simple cubic lattice, a face centered cubic lattice and a liquid-like structure. The particles are coupled by long-range dipolar forces and present a single ion uniaxial anisotropy, whose magnitude is chosen from a Gaussian distribution, and whose easy magnetization axes are oriented randomly in the three-dimensional space. We determined the blocking temperature and the hysteresis curves as a function of the ratio between the magnitude of dipolar coupling and uniaxial anisotropy. We show that the remanence and coercive field depend strongly on the nature of the magnetic arrangement. These results are compared with those found for a system of noninteracting particles. [ABSTRACT FROM AUTHOR]

Adsorption of solvent or organic compounds at a metal/interface is characterized by a wide spectrum of interactions governing the phenomenon under effective fields of order ≈ 107V/cm. A generalized spin-1 Ising Hamiltonian was formulated by considering various interactions under molecular field approximation (MFA) to arrive at a three-state model of adsorption isotherm (i.e. the joint adsorption of two different organic compounds in the presence of solvent molecules). A general multi-state model was deduced heuristically and an expression for the charge $(\sigma_{\max}^{M})$ at which maximum adsorption (θmax) occurs derived explicitly for a three-state site parity model that incorporates short-range interaction energies, functional dependence of permanent and induced dipole moments of the organic adsorbate, and the solvent and substrate interactions. [ABSTRACT FROM AUTHOR]