Estudio de nanomateriales modificados basados en Au mediante espectroscopía de resonancia de plasmones de superficie

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Física de Materiales, leída el 14-03-2014In this work, surface plasmon resonance (SPR) spectroscopy has been employed as a probe to study modifications in nanostructured systems based on Au. Those modifications include a) structural and morphological changes induced by annealing and b) electronic modifications upon X-ray irradiation. The use of SPR spectroscopy to follow the evolution of modifications in nanostructures (especially, in situ and in real time) has been scarcely explored and its study results interesting and relevant for the plasmonic technology. In this first part of the work, we have grown nanostructures from Au films and Au/Fe bilayers which have been later annealed under different conditions. These nanostructures have been characterized morphologically and analyzed by SPR spectroscopy, in order to follow the morphological changes of the systems varying the sample features (i.e., initial thickness) and the annealing conditions. With the purpose of studying changes induced upon X-ray irradiation using SPR as a probe, we have designed and developed a SPR system based on the Kretschmann-Raether configuration compatible with a X-ray absorption spectroscopy (XAS) beamline (SPR-XAS setup). Using this device, a study of the effects of the X-rays on glasses and Co-Phthalocyanines (CoPcs) has been carried out. For the study on glasses, two different types are analyzed: soda-lime and silica substrates, and for the case of the CoPcs, these have been grown varying the film thickness and the growth conditionsEn este trabajo se ha empleado la espectroscopía de resonancia de plasmones de superficie (SPR) para estudiar modificaciones en sistemas nanoestructurados basados en Au. Estas modificaciones incluyen a) cambios estructurales y morfológicos inducidos mediante tratamientos térmicos y b) modificaciones electrónicas bajo irradiación con rayos X. El uso de la espectroscopía de SPR para seguir la evolución de modificaciones en nanoestructuras (especialmente, in situ y en tiempo real) ha sido escasamente explorado y su estudio resulta interesante y relevante para el campo de la plasmónica. En la primera parte de este trabajo se ha llevado a cabo la fabricación de nanoestructuras a partir de películas de Au y bicapas Au/Fe tratadas térmicamente bajo diferentes condiciones. Estas nanoestructuras han sido caracterizadas morfológicamente y analizadas mediante espectroscopía de SPR con el fin de estudiar los cambios estructurales inducidos en las muestras al variar parámetros como el espesor y las condiciones del tratamiento térmico. Con el objetivo de estudiar modificaciones inducidas en la materia bajo irradiación con rayos X usando la SPR como sonda, se ha diseñado y desarrollado un sistema experimental de SPR basado en la configuración de Kretschmann-Raether y compatible con la espectroscopía de absorción de rayos X (dispositivo SPR-XAS). Mediante este montaje experimental se han analizado los efectos inducidos por los rayos X en vidrios y en Ftalocianinas de Co (CoPcs), in situ y en tiempo real. Para el caso de los vidrios, dos tipos diferentes han sido empleados como substratos: sodicocálcicos y de sílice. Por otro lado, las CoPcs estudiadas han sido crecidas variando su espesor y las condiciones de crecimientoDepto. de Física de MaterialesFac. de Ciencias FísicasTRUEunpu

Modified Au-based nanomaterials studied by surface plasmon resonance spectroscopy

Tesis Doctoral realizada por Aída Serrano Rubio en la Universidad Complutense de Madrid (Facultad de Ciencias Físicas. Departamento de Física de Materiales) y el CSIC - Instituto de Cerámica y Vidrio (ICV).[EN]: In this work, surface plasmon resonance (SPR) spectroscopy has been employed as a probe for studying modifications in nanostructured systems based on Au. Those modifications include: a) structural and morphological changes induced by annealing and b) electronic modifications upon X-ray irradiation. The use of SPR spectroscopy to follow the evolution of modifications in nanostructures (especially, in situ and in real time) has been scarcely explored and its study results interesting and relevant for the plasmonic technology. For that, different experiments have been planned and performed.[ES]: En este trabajo se ha empleado la espectroscopía de resonancia de plasmones de superficie (SPR) para estudiar modificaciones en sistemas nanoestructurados basados en Au. Estas modificaciones incluyen: a) cambios estructurales y morfológicos inducidos mediante tratamientos térmicos y b) modificaciones electrónicas bajo irradiación con rayos X. El uso de la espectroscopía de SPR para seguir la evolución de modificaciones en nanoestructuras (especialmente, in situ y en tiempo real) ha sido escasamente explorado y su estudio resulta interesante y relevante para el campo de la plasmónica. Para llevar a cabo la realización de este trabajo, varios experimentos han sido planteados y realizados.La realización de este trabajo de tesis doctoral ha sido posible gracias a la fianciación de los proyectos de investigación BONSAI (LSHB-CT-2006-037639) and MAGNYFICO (NMP4-SL-2009-228622) financiados por la Unión Europea. El Ministerio de Economía y Competitividad y el Consejo Superior de Investigaciones Cientifícas son también agradecidos por la financiación y la provisión de las instalaciones de radiación sincrotrón en BM25-Spline, en el ESRF. Aída Serrano Rubio agradece la financiación otorgada por el Consejo Superior de Investigaciones Científicas con una Beca JAE (JAEPre096) de cuatro años de duración para desarrollar la tesis doctoral en el Instituto de Cerámica y Vidrio.Peer Reviewe

RESEÑA de: Radicalism and Terrorism in the 21 st Century. Implications for Security. Studies in politics, security and society Vol.9. Peter Lang Edition. Frankfurt, 2017. 321 págs. Anna Sroka, Fanny Castro-Rial Gorrone, Rubén Darío Torres Cumbrián (eds.)

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Influencia de los factores motivacionales en el rendimiento laboral de los trabajadores CAS de la municipalidad distrital de Carabayllo

En la presente tesis titulada “Influencia de los factores motivacionales en el rendimiento laboral de los trabajadores CAS de la Municipalidad Distrital de Carabayllo”, tiene como objetivo determinar cuáles son los factores motivacionales que influyen en el rendimiento laboral de los trabajadores de Contrato Administrativo de Servicio (CAS) de la Municipalidad de Carabayllo. La presente investigación es de tipo descriptivo correlacional, con una muestra de 104 participantes, a través de una encuesta que mide las dos variables, se obtuvo como resultado: apreciar la existencia de correlación significativa al nivel del 0.05 de la variable Factores motivacionales con la variable Rendimiento laboral los resultados indican que existe un 97.7 % de confianza de que las correlaciones sean verdaderas y una probabilidad de error menor al 5%. De acuerdo a la tabla de valores de Ch2, la correlación encontrada = 3,1052 para la correlación respectivamente, con lo que validamos nuestra hipótesis alterna que sugiere que “Los factores motivacionales influyen de manera significativa en el rendimiento laboral de los trabajadores CAS de la Municipalidad Distrital de Carabayllo”, validándola. Palabras claves: Motivación, factores, rendimiento laboral, Motivación extrínseca, Motivación intrínseca.--- This research entitled "Influence of motivational factors in the working efficiency of the CAS workers Carabayllo District Municipality" aims to Identify the motivational factors that influence job performance of workers Administrative Service Agreement are (CAS) of the Municipality of Carabayllo. This research is descriptive correlated. With a sample of 104 participants, through a survey that measures two variables. It was as a result: a finding of significant at the 0.05 of the variable motivational factors with variable correlation labor Performance results indicate a 97.7% confidence that the correlations are true and probability of error less than 5%. According to the table of values Ch2, the correlation found for correlation = 3.1052 respectively, which validate our alternate hypothesis that "The motivational factors have a significant influence on the labor performance of CAS workers MDC "validating. Keywords: Motivation factors, work performance, extrinsic motivation, intrinsic motivationTesi

Cognitive rehabilitation in a case of traumatic brain injury using EEG-based neurofeedback in comparison to conventional methods.

Severe traumatic brain injury residual cognitive impairments significantly impact the quality of life. EEG-based neurofeedback is a technique successfully used in traumatic brain injury and stroke to rehabilitate cognitive and motor sequelae. There are not individualized comparisons of the effects of EEG-based neurofeedback versus conventional neuropsychological rehabilitation. We present a case study of a traumatic brain injury subject in whom eight sessions of a neuropsychological rehabilitation protocol targeting attention, executive functions, and working memory as compared with a personalized EEG-based neurofeedback protocol focused on the electrodes and bands that differed from healthy subjects (F3, F1, Fz, FC3, FC1, and FCz), targeting the inhibition of theta frequency band (3 Hz−7 Hz) in the same number of sessions. Quantitative EEG and neuropsychological testing were performed. Clear benefits of EEG-based neurofeedback were found in divided and sustained attention and several aspects related to visuospatial skills and the processing speed of motor-dependent tasks. Correlative quantitative EEG changes justify the results. EEG-based neurofeedback is probably an excellent complementary technique to be considered to enhance conventional neuropsychological rehabilitation.post-print1462 K

Improving the co and ch4 gas sensor response at room temperature of alpha-fe2o3(0001) epitaxial thin films grown on srtio3(111) incorporating au(111) islands

In this work, the functional character of complex -Fe2O3(0001)/SrTiO3(111) and Au(111) islands/ -Fe2O3(0001)/SrTiO3(111) heterostructures has been proven as gas sensors at room temperature. Epitaxial Au islands and -Fe2O3 thin film are grown by pulsed laser deposition on SrTiO3(111) substrates. Intrinsic parameters such as the composition, particle size and epitaxial character are investigated for their influence on the gas sensing response. Both Au and -Fe2O3 layer show an island-type growth with an average particle size of 40 and 62 nm, respectively. The epitaxial and incommensurate growth is evidenced, confirming a rotation of 30 between the in-plane crystallographic axes of -Fe2O3(0001) structure and those of SrTiO3(111) substrate and between the in-plane crystallographic axes of Au(111) and those of -Fe2O3(0001) structure. -Fe2O3 is the only phase of iron oxide identified before and after its functionalization with Au nanoparticles. In addition, its structural characteristics are also preserved after Au deposition, with minor changes at short-range order. Conductance measurements of Au(111)/ -Fe2O3(0001)/SrTiO3(111) system show that the incorporation of epitaxial Au islands on top of the -Fe2O3(0001) layer induces an enhancement of the gas-sensing activity of around 25% under CO and 35% under CH4 gas exposure, in comparison to a bare -Fe2O3(0001) layer grown on SrTiO3(111) substrates. In addition, the response of the heterostructures to CO gas exposure is around 5–10% higher than to CH4 gas in each case.This work has been supported by the Ministerio Español de Ciencia e Innovación (MICINN) and the Consejo Superior de Investigaciones Cientificas (CSIC) through the projects PIE-2010-OE-013- 200014, PIE 2021-60-E-030 and RTI2018-095303-A-C52. The ESRF, MICINN and CSIC are acknowledged for the provision of synchrotron radiation facilities. A.S. acknowledges financial support from Comunidad de Madrid for an “Atracción de Talento Investigador” Contract (2017-t2/IND5395)

A new paradigm in university teaching based on digital skills for teachers

Este artículo aborda la necesaria adaptación de los métodos de enseñanza y aprendizaje de las universidades para dar respuesta a las necesidades del estudiantado, que cada vez percibe más el riesgo de la interrupción de sus estudios, debido a situaciones de crisis, como son conflictos armados, desastres naturales, recesiones económicas o alertas sanitarias. Para ello, se expone en primer lugar el contexto de la educación universitaria respecto a las competencias digitales de sus profesores y las necesidades de adaptación a modelos docentes digitalizados. A continuación, se expone la utilidad las herramientas digitales, así como la necesaria adquisición y desarrollo de competencias digitales de los profesores universitarios. Seguidamente, se explican las principales dimensiones que integran la competencia digital docente. Finalmente, se expone el proceso de adquisición de competencias digitales de cada profesor, a través de proyectos de capacitación en abierto y gratuitos, a través de plataformas digitales, flexibles y adaptadas a la disponibilidad y medios de cada docente, ofreciendo una planificación de itinerarios de formación personalizados.This article addresses the necessary adaptation of the teaching and learning methods of universities to respond to the needs of students, who increasingly perceive the risk of the interruption of their studies, due to crisis situations, such as armed conflicts, natural disasters, economic recessions or health alerts. To do this, the context of university education is exposed in the first place regarding the digital skills of its teachers and the needs to adapt to digitized teaching models. Next, the usefulness of digital tools is exposed, as well as the necessary acquisition and development of digital skills of university professors. Next, the main dimensions that make up the digital teaching competence are explained. Finally, the process of acquiring digital competences of each teacher is exposed, through open and free training projects, through digital platforms, flexible and adapted to the availability and means of each teacher, offering a planning of itineraries of personalized training

Thermal route for the synthesis of maghemite/hematite core/shell nanowires

Nowadays, iron oxide-based nanostructures are key materials in many technological areas. Their physical and chemical properties can be tailored by tuning the morphology. In particular, the possibility of increasing the specific surface area has turned iron oxide nanowires (NWs) into promising functional materials in many applications. Among the different possible iron oxide NWs that can be fabricated, maghemite/hematite iron oxide core/shell structures have particular importance since they combine the magnetism of the inner maghemite core with the interesting properties of hematite in different technological fields ranging from green energy to biomedical applications. However, the study of these iron oxide structures is normally difficult due to the structural and chemical similarities between both iron oxide polymorphs. In this work, we propose a route for the synthesis of maghemite/hematite NWs based on the thermal oxidation of previously electrodeposited iron NWs. A detailed spectroscopic analysis based on Raman, Mossbauer, and X-ray absorption shows that the ratio of both oxides can be controlled during fabrication. Transmission electron microscopy has been used to check the core/shell structure of the NWs. The biocompatibility and capability of internalization of these NWs have also been proven to show the potential of these NWs in biomedical applications

Interlayer-Confined Cu(II) Complex as an Efficient and Long-Lasting Catalyst for Oxidation of H2S on Montmorillonite

Removal of highly toxic H2S for pollution control and operational safety is a pressing need. For this purpose, a montmorillonite intercalated with Cu(II)-phenanthroline complex [Cu[(Phen)(H2O)2]2+ (Mt-CuPhen) was prepared to capture gaseous H2S under mild conditions. This hybrid material was simple to obtain and demonstrated an outstanding ability to entrap H2S at room temperature, retaining high efficiency for a very long time (up to 36.8 g of S/100 g Mt-CuPhen after 3 months of exposure). Sorbent and H2S uptake were investigated by elemental analysis, X-ray powder diffraction measurements, diffuse reflectance (DR) UV–Vis and infrared spectroscopy, thermal analysis and evolved gas mass spectrometry, scanning electron microscopy equipped with energy-dispersive X-ray spectrometer, and X-ray absorption spectroscopy. The H2S capture was studied over time and a mechanism of action was proposed. The entrapping involves a catalytic mechanism in which [Cu[(Phen)(H2O)2]2+ acts as catalyst for H2S oxidation to S0 by atmospheric oxygen. The low cost and the long-lasting performance for H2S removal render Mt-CuPhen an extremely appealing trap for H2S removal and a promising material for many technological applications