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106 páginas, 70 figuras, 1 tabla. Discurso leído en el acto de su recepción como Académico de Número por el Excmo. Sr. D. Ernesto Carmona Guzmán y contestación del Excmo. Sr. D. Miguel Ángel Alario y Franco, el día 25 de abril de 2007., Este discurso trata sobre compuestos organometálicos, sustancias químicas que contienen enlaces metal-carbono, y los elementos químicos protagonistas del discurso serán, de una parte C y del otro los metales que constituyen el 80% de los elementos químicos conocidos. Se describe la importancia de como surgió la química organometálica moderna, tras la preparación y el reconocimiento de la estructura de tipo sandwich del ferroceno, y se discute la importancia de los metalocenos en diferentes campos de la Química actual.

Proceedings of the Fourth European Conference on Applied Superconductivity, held at Sitges, Spain, 14-17 September 1999 (Superconductivity Conference//Proceedings).-- X. Obradors; F. Sandiumenge; J. Fontcuberta (eds.)

9 páginas., Superconducting films of the Bi ¾ Sr ¾ Ca ¾ Cu ¾ O family of oxides were prepared by electrodeposition of the constituent metals followed by an oxidative thermal treatment. The influence of water, stirring of the electrolyte, cleaning of the substrate, and deposition time on the quality of the films were studied. Before the thermal treatment, the electrodeposited films consisted of a mixture of different metals and carbonates of the constituent elements. The oxidation of the metallic phases and the decomposition of the carbonates occurred in the ranges 260 ¾ 280 °C and 400 ¾ 470 °C, respectively. The final oxides were obtained after an oxidative thermal treatment of 800 °C. Lower temperatures were not sufficient for the preparation of the superconducting oxide films. The prepared Bi-2201 films consisted of a mixture of two phases with different strontium, bismuth, and oxygen content. The Bi-2212 films were composed of platelike particles with a preference to orientate along the (001) direction. These films showed critical temperatures up to 92 K and critical current densities up to 15,000 A/cm2 (at 77 K and zero field) when the films were pressed before the thermal treatment.

5 páginas.-- Published proceedings article from Symposium DD from the 1998 MRS Fall Meeting.-- Edited by E.M. McCarron III, H-C. zur Loye, S.M. Kauzlarich, A.W. Sleight, Electrodeposition of multimetallic films at room temperature on metallic substrates followed by oxidation at high temperature (-900'C) has often been employed to prepare high temperature superconducting (HTSC) films. A difficulty with this otherwise cheap and simple process is that the degree of surface covering is usually not very high. We have attempted to remediate this problem by sequentially repeating the deposition process on the same film. In this way, we have improved quite markedly critical current density (Jo) of films obtained on Silver substrates. To quote some figures, J, at 1 T is -400 A/cm 2 after the first deposition/oxidation process and it increases to -2 000 A/cm 2 after the fourth one. The evolution of the morphology of the films has been followed by means of scanning electron microscopy (SEM). It shows that, although the degree of surface coverage never attains 100 %, a substantial proportion of the substrate is well coated. We have also studied the influence of mechanical pressure on the metallic film before the thermal treatment; after the fourth deposition, a pressure of-15 KBar was applied. In this case a -7% increase in Jc was observed and the density after compression (6.98 g/cm 3) attains almost 100 % ofthe theoretical value for YBa2Cu307.6 (Ybacuo).

6 páginas.-- Proceedings of the NATO Advanced Research Workshop on High-Temperature Superconductors and Novel Inorganic Materials Engineering MSU-HTSC V, Moscow, Russia, March 24-29, 1998.-- Van Tendeloo, G.; Antipov, E.V.; Putilin, S.N. (Eds.)

273 páginas.-- Memoria para optar al grado de Doctor presentada por María de la Soledad Martín González., No hubiera sido posible la realización del presente trabajo sin la financiación aportada por diversos organismos: Fundación General de la Universidad Complutense de Madrid (beca para la realización trabajo de investigación bajo la dirección del Prof Dr. Miguel Á. Alarmo y la recopilación de datos para las líneas de investigación y servicios de la Complutense, que dieron origen a 4 libros) y la CICYT (Mat 95-0809 y Mat 980729).