Vol. 103 No. 3 (2007)

This paper shows the potential applications of new photoactive materials based on the intercalation of fluorescent dyes into ordered clay films. The intercalation of rhodamine 6G (R6G) into laponite (Lap) films improves the thermostability and the fluorescent efficiency of the dye, although the emission ability decreases by increasing the dye loading due to the dye aggregation. The dye aggregation induces new absorption and fluorescence bands, rising the spectral region in which these materials are photoactives. These materials show an anisotropic behaviour with respect to the plane of the linearly polarized light, improving the applicability of these films in non-linear optics.

In the whole Universe it is possible to find organic complex substances known with the generic name of tholins. These substances are obtained by irradiation of several gas mixtures (excluding the O₂). The analysis of the tholins indicates that they can release important bio organics present in proteins, nucleic-acid bases and so on. It has been proposed that the tholins could play an important role in the appearance of life on the Earth. The Chemical Evolution Theory parts from this type of substances to explain as the first living organism could arise.

The aim of this paper is to study the family of halobenzenes for characterizing their intrinsic reactivity and in this way to establish a rational order of the intrinsic reactivity of this family of molecules in the electrophilic aromatic substitution. This study was carried out in the framework of Density Functional Theory which provides a global and local index that can be used in the characterization of the reactivity. This index is related to some concept derivates of experiment chemistry, being a good approach to the characterization of halobenzenes.

Keywords: Density functional theory, halobenzenes, electrophilicity, reactivity, local index.

In the recent years, aluminium metal matrix composites have been promoted from science interest to commercial applications, especially inside the automotive sector, where materials of mechanical strength/density ratios are demanded, trying to reduce the fuel consumption and the pollutant emissions. Nevertheless, a lower oxidation and corrosion resistance have been observed for these materials, frequently associated to the active matrix/reinforcement interfaces. In the present work, novel methodologies and techniques for fighting against to the degradation problems of aluminium matrix composites are evaluated, such as, surface modification by lanthanide salts and laser surface melting treatments.

Keywords: Materiales compuestos, oxidación, corrosión localizada, tratamientos superficiales láser, sales lantánidas.

Teniendo en cuenta al mismo tiempo coste y efectividad, las técnicas espectroscópicas tienen una importancia creciente dentro de la industria química en general. Este trabajo proporciona una valiosa fuente de información sobre los adelantos tecnológicos en el área de la espectrometría de masas y su evolución histórica referente a sus aplicaciones dentro de la Química Ambiental.

The phenomenon of Electrochemical Promotion also called NEMCA effect is a recent discovered phenomenon that enables to improve electrochemically the catalytic behaviour of metal catalysts, increasing the catalytic activity and selectivity. Our research group studies the application of this phenomenon to improve the behaviour of several catalysts for the Selective Catalytic Reduction of NOx . This paper deals with some important aspects of this phenomenon such us the origin and mechanism of the NEMCA effect, the preparation of the electrochemical catalyst and the electrochemical cell reactor. In addition, some of the most representative obtained results are discussed.

In a Training and Educational Innovation Centre of the Basque Government Department of Education, during the 2006/07 school year a training course addressed to teaching staff in Obligatory Secondary School (O.S.E.) has taken place. The course's purpose was to provide teachers with motivating experiences which could encourage the students in their interest in chemistry and in the same way these experiences tried to be easy to be put into practice with the endowment that secondary schools usually have. This article describes the just quoted training activity and shows the obtained results as well as some conclusions that can be drawn from them.

In this second part we analyze the role played by Institute of Applied Chemistry (IQA) and Chemical Institute of Sarriá (IQS), two Catalan institutions at margin of official establishments of teaching that promoted the training of specialists for chemical industry. At the same time we will show how Faculties of Sciences were mobilized in order to incorporate chemists to national industry. We highlight the changes of curriculum happened in 1922 and in Second Republic, and the introduction of Technical Chemistry as an academic discipline that allowed chemists pass from laboratory to chemical plant, as well as the incorporation of diverse matters of strong industrial character.