The poly(o-aminophenol) (POAP) redox process has been studied in aqueous acid solution using spectroscopic and optic in situ
techniques. The redox transition of the POAP from its completely oxidized state to its completely reduced state occurs through two
consecutive reactions…

The harmonic balance method is used to construct approximate frequency–amplitude relations and periodic solutions to the relativistic oscillator. By combining linearization of the governing equation with the harmonic balance method, we construct analytical approximations to the oscillation frequencies and periodic…

Realistic mathematical models are of great importance for studying the optical performance of the human eye. Light propagation algorithms provide robust methods to calculate field distributions inside a homogeneous medium, and thus they can be applied to the study of…

In order to achieve a better understanding of the mechanisms of hologram formation and higher diffraction efficiencies in volume gratings stored in acrylamide based photopolymers, a crosslinker (N,N'methylene-bis-acrylamide) has been incorporated in the photopolymer to record holograms by pulsed laser…

The electrochemical regeneration of an activated carbon, previously saturated with toluene by gas phase adsorption, was studied. Cathodic and anodic regeneration methods were analyzed using a small batch electrochemical cell. In both cases, a stripping efficiency close to 100% was…

The kinetics of photosensitive polymer holographic recording materials are examined assuming a material that exhibits nonideal kinetic behavior. Previously, a linear relationship between monomer concentration and polymerization was assumed when deriving the nonlocal polymer-driven diffusion (NPDD) model. This is consistent…

Our intention in this paper is to shortly address some of the basic categories that determine the paradigm of sport culture as we know it. We do believe that by understanding these basic categories the changes of prevailing sport paradigm,…

The current study attempts to describe the free time of City of Havana (Cuba) population older than 15 years, distinguishing between word days, weekends and vacation and holiday periods, determining the population's socio-demographic profile. The object population of study numbers…

This paper deals with the non-linear oscillation of a simple pendulum and presents an approach for solving the non-linear differential equation that governs its movement by using the harmonic balance method. With this technique it is possible to easily obtain…

The aims of this study were to describe body composition and physical fitness changes during a whole-season in elite children tennis players. A total of 7 elite children tennis players participated in the study. Whole body composition by dual energy…