A new analytical approximate expression for the period of the simple pendulum is obtained by using a heuristic but pedagogical derivation. This formula depends on two parameters obtained by comparing term-by-term the power-series expansions of the approximate and exact expressions…

This paper addresses the influence of information technology in human resources management (HRM) and specifically on training policy through the experience of a Spanish telecommunications firm, Telefonica. The characteristics of the training model designed by this firm to face new…

The electrochemical homo-polymerization of o-, m- and p-aminobenzoic acids has been performed on Pt electrodes in perchloric acid aqueous medium by cyclic scanning of the potential. Different limit potentials were employed to obtain thin polymeric films. When the switching potential…

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…

Despite its frequent use, there is little understanding of the concept of differential
among upper high school and undergraduate students of physics. As a first step to identify the origin of this situation and to revert it, we have done…

The electrochemical oxidation of the aniline dimers 2-aminodiphenylamine (2-adpa) and 4-aminodiphenylamine (4-adpa) has been
performed in strongly acidic medium on platinum, graphite, and indium tin oxide electrodes. The resulting films have been
characterized by a number of electrochemical, microscopic, and…

The redox process undergone by the electrochemically synthesized poly(2,2-dithiodianiline), poly(DTDA), has been examined in
acetonitrile-water mixtures by electrochemical and spectroscopic techniques. The spectroscopic properties of this material are equivalent to those exhibited by the chemically synthesized one. The polymeric structure…

Aniline (ANI) and 2-aminoterephthalic acid (2ATA) copolymers, with different compositions, were prepared by
chemical oxidative polymerization varying the feed ratio. The new materials have been characterized by techniques such
as XPS, FTIR, Raman spectroscopies and thermal analysis. It has been…

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 effect of adding Sn to Pt/CeO2–Al2O3 and Pt/Al2O3 catalysts was studied with X-ray photoelectron spectroscopy (XPS), 119Sn Mössbauer
spectroscopy, and adsorption microcalorimetry of CO at room temperature. Catalysts were reduced in situ at 473 (non-SMSI state) and 773 K