The role of interfaces in CoFe/IrMn exchange biased systems

A trilayer system consisting of an IrMn layer exchanged coupled to two CoFe layers of equal thickness has been studied. A single stage reversal was observed over a wide range of temperatures. Two bilayers with the same thicknesses of the pinning layer but different ferromagnetic thicknesses were also studied. By comparing the magnetic properties of these three stacks the effect of the interfacial area on the exchange field and the coercivity has been determined. We find that the interfacial area has a very minor effect on the exchange field H-ex and the blocking temperature (T-B) but causes a doubling of the coercivity (H-c). This indicates that H-c is dominated by the interface whereas the exchange bias is controlled by volumetric effects

Measurement protocols for exchange biased systems

A study of exchange biased systems has been made focused on the development of measurement protocols that yield measurement reproducibility. The materials studied were IrMn(tAF)/CoFe(10nm) thin films, with tAF being 3nm and 5nm. These materials were selected due to their industrial applications. The thicknesses were chosen as they were the most appropriate for the purpose of this study. Vibrating sample magnetometry has been used to investigate thermal activation properties in the set of samples. The measurement protocols developed allowed measurement reproducibility. They lead to a better understanding of the exchange biased phenomenon. It was found that the changes occurring in the exchange biased systemsd uring measuremenat re due to thermal activation in the antiferromagneticl ayer which reduced the degree of order within the antiferromagnet. It was observed that the peak in the coercivity with the temperature of thermal activation does not correlate with the median blocking temperature. A study of training effects and their behaviour with temperature has led to the identification of three different contributions to exchange bias which are spin freezing, spin reorientation, and thermal activation. Each of these effects contribute to the shift of the hysteresis loop and the coercivity of exchange biased systems through different mechanisms. The results obtained are consistentw ith a grain size dependenceo f the exchangeb ias phenomenon, and are in accordance with grain models of exchange bias. Also, the measurement protocols obtained have been used by other researchers in FeMn/NiFe exchange coupled bilayers. The results obtained were in accordance with the conclusions of this thesi

Idoneidad de la educación física para el aprendizaje integrado de contenidos en lengua extranjera (AICLE)

El interés de este trabajo procede del creciente desarrollo de experiencias de Aprendizaje Integrado de Lenguas Extranjeras (AICLE). El objetivo que persigue es conocer hasta qué punto la materia de Educación Física resulta idónea para aplicar estos preceptos metodológicos. La metodología aplicada consistió en la revisión documental y el análisis de caso, siendo éste las experiencias AICLE desarrolladas por un mismo docente en la materia de Educación Física durante cinco cursos académicos en un centro educativo público español. Como resultado de la investigación, fue posible identificar seis especificidades propias de la materia que la hacen altamente recomendable para el aprendizaje integrado de lenguas extranjeras. Si las conclusiones permiten recomendar la aplicación de metodología AICLE en la materia de Educación Física, la discusión va encaminada a valorar en qué medida en otras materias es posible crear esas condiciones favorables para facilitar la expansión de la metodología AICL

Insistencias: Viejas inquietudes, nuevas inquietudes de los Game Studies

El juego, actividad lúdica inherente al ser humano, es fundamental para el desarrollo de las personas como elemento de exploración del mundo.&nbsp

Comics, graphic narratives, and lesbian lives

Lesbian comics and graphic narratives have gained unprecedented cultural presence in the twenty-first century. Yet despite the surge in interest in the work of artists such as Alison Bechdel, and despite the existence of a substantial online archive about lesbian comics created by artists, readers, and collectors, relatively little critical attention has been directed to this work. The chapter begins to fill this gap. Taking the Bechdel’s work as its start-and-end point, it provides an overview of major developments in lesbian comics and contextualises them including in relation to the gendered conditions of possibility that define comics culture

Application of nickel ferrite nanoparticles in adsorption of amoxicillin antibiotic

According to the World Health Organization, amoxicillin (AMX) is the most widely consumed antibiotic in the world. Consequently, there is great interest in the development of new technologies that allow the removal of this type of contaminant, as exposure to antibiotic residues can cause a variety of adverse effects, such as toxicity and antimicrobial resistance. In this work, AMX adsorption from aqueous solution was investigated using nickel ferrite nanoparticles. The nanoadsorbents were prepared by the coprecipitation method, annealed at 300 to 700 °C, and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Mössbauer spectroscopy (ME) and vibratory sample magnetometry (VSM). Nanoparticle size, pH and temperature were found to significantly affect the amount of adsorbed AMX. The pseudo-second order kinetic model described the adsorption process and the adsorption isotherm fitted to the Freundlich model. AMX adsorption capacity was 104-45 mg g−1 (miligram of AMX per gram of ferrite) for ferrite annealed at 300-700 °C, respectively. The nanoadsorbents employed showed higher AMX removal efficiency when compared to other iron oxides. Moreover, the good reuse results obtained showed their great potential for antibiotic removal by adsorption.CNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas GeraisCAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Growth of carbon structures on chrysotile surface for organic contaminants removal from wastewater

Amphiphilic magnetic composites were produced based on chrysotile mineral and carbon structures by chemical vapor deposition at different temperatures (600–900 °C) and cobalt as catalyst. The materials were characterized by elemental analysis, X-ray diffraction, vibrating sample magnetometry, adsorption and desorption of N2, Raman spectroscopy, scanning electronic microscopy, and thermal analysis showed an effective growth of carbon structures in all temperatures. It was observed that at 800 and 900 °C, a large amount of carbon structures are formed with fewer defects than at 600 and 700 °C, what contributes to their stability. In addition, the materials present magnetic phases that are important for their application as catalysts and adsorbents. The materials have shown to be very active to remove the oil dispersed in a real sample of emulsified wastewater from biodiesel production and to remove methylene blue by adsorption and oxidation via heterogeneous Fenton mechanism.CNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas GeraisOutra Agênci

El círculo del arte y la cultura de masas.Tensiones y divergencias.

Cómo se configura y comporta la obra de arte a partir de lairrupción del objeto como presentación y no como representación, analizado desde Arthur C. Danto y George Dickie; a su vez cómo esta configuración lleva a un complot del arte, en palabras de Jean Baudrillard, impidiendo la discusión sobre determinadas producciones. El kitsch es analizado desde la problemática del kitscheo, elemento introducido para discutir la exclusión de los sectores populares de los círculos legitimados del arte.Fil: Outon, Carolina. Universidad Nacional de Rosario. Facultad de Humanidades y Artes. Escuela de Bellas Artes; Argentina