A hyphenated technique based on vis–NIR spectroscopy and electrochemical quartz crystal microbalance with motional resistance monitoring was employed to investigate the dissolution of copper in acid media. Changes in motional resistance, current, mass, and absorbance during copper dissolution allow the evolution of the interfacial region of copper|diluted sulfuric solution to be understood. In particular, motional resistance is presented in this work as a useful tool to observe the evolution of the passive layer at the interface. During the forced copper electrodissolution in sulfuric solution, SO4(2–) favors the formation of soluble [Cu(H2O)6]2+. On the contrary, OH– involves the formation of Cu(H2O)4(OH)2, which precipitates on the electrode surface. The high viscosity and density of Cu(H2O)4(OH)2 formed on surface causes an increase in motional resistance independently of resonance frequency changes. During the copper corrosion in a more natural acidic environment, the results of electrochemical impedance spectra at open circuit potential indicate that corrosion is controlled by the diffusion of copper to the solution at short experimental times. However, copper diffusion is hindered by the formation of a passive layer on the electrode surface at long experimental times. During the copper corrosion, motional resistance shows an oscillatory response because of an oscillatory formation/dissolution of the passive later. Vis–NIR spectroscopy and electrochemical quartz crystal microbalance with motional resistance monitoring give new perspectives for reaching a deep understanding of metal corrosion processes and, in a future, other interfacial processes such as the catalysis or adsorption of (bio)molecules.

The simultaneous measurement of current, mass, motional resistance and absorbance magnitudes allows the electrochemical cation insertion process to be explained during successive voltammograms around the Prussian Blue ⇄ Everitt's Salt system in CsCl aqueous acid solutions. Two different ways for the entrance of cesium to the porous structure of Prussian Blue have been observed. Firstly, Cs + is spontaneously absorbed as CsCl into the interstitial cluster of water of the channels formed by the

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This book seeks to deepen the principle of legal equality, its scope and content in front of certain population. In the same way as its extension to other subjects, under the methodology of legal dogmatics, it seeks a bibliographic and jurisprudential review within the project “The challenges of contemporary private law in the context of the constitutional debate and new developments in the economy”, of the Group Study in Private Law and Intellectual Property in the line of research Private Law. The foregoing within the framework of the constitutionalization of national private law, and comparative private law studies at the Catholic University of Colombia. The purpose of this book is to offer to the academic community states of the art that facilitate the subsequent formulation of research projects to allow the study, understanding and dimension of the subject of rights as a category that transcends the traditional concept of person in their search for legal equality in situations related to age, sex, gender, disability, economic conditions, and others. All within the era of the constitutionalization of private law.