Sulfuros de metales de transición en película delgada para aplicaciones termoeléctricas y fotovoltaicas: formación y dopaje

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física de Materiales. Fecha de lectura: 22-06-0

Enhanced Power Factor of PANI/GNP nanocomposites

Comunicación presentada en la 11th European Conference on Thermoelectrics (ECT2013), celebrada en Noordwijk (Holanda) del 18 al 20 de noviembre de 2013.Nowadays, the inorganic compounds (like Bi2Te3) are the best thermoelectric materials due to their suitable thermoelectric properties for room temperature applications. Nevertheless, organic materials, like conjugated polymers, are becoming more important recently due to their increasing Figure of Merit (0.25‐0.42). Polymers generally have low thermal conductivity (©§≈0.1‐0.5W/m∙K), flexibility, environmental stability, easily doping and de‐doping, non‐toxicity, potential processing advantages (e.g. printing) and straightforward preparation in comparison with inorganic semiconductors. The increase in the Power Factor of this materials, which is given by S2¥ò, is being achieved by two mechanisms: doping the polymers or blending them with different kinds of filling materials, such as carbon nanotubes, graphene nanosheets (GN) or graphene nanoplatelets.Peer Reviewe

Optimization of bismuth telluride films and nano-wire arrays via electrodeposition for thermoelectric applications

Comunicación presentada en el 3rd Early Stage Researchers Workshop in Nanoscience, celebrado en Madrid el 27 y 28 de junio de 2013.Due to the current world’s demand for energy, there is a great interest in thermoelectricity, which offers the possibility of increasing the sustainability of our electrical system. Thermoelectric materials can convert heat into electricity and vice versa, and thus they offer a way of recovering wasted heat produced in engines, industrial processes and others into usable power. However, one of the main problems for their actual use is their low efficiency in this conversion. This efficiency is directly related with what is called the thermoelectric figure of merit, described by ZT=(S2·σ·T)/κ ,where S, σ, κ, and T stand for the Seebeck coefficient, electrical and thermal conductivities, and the absolute temperature, respectively. Given that in classical physics S, σ, and κ, are correlated, the improvement of the efficiency is not straightforward. Nevertheless, in 1993 a theoretical work suggested that the efficiency could be greatly enhanced by reducing the dimensionality of the structures under studied and working in the nano-scale. Therefore, much experimental effort has been done to achieve these kind of structures and in some cases, an enhancement of the ZT value has been achieved, although this has not been due to the quantum confinement to the charge carriers, as it was theoretically predicted, but to an increase of the κ due to the increased number of interface boundaries in nanostructures. Among the most efficient thermoelectric materials used for applications at room temperature, bismuth telluride (Bi2Te3) and its different alloys stand out, with a ZT for Bi2Te3of around 1 at RT [2]. We present here an optimized method of obtaining films and nanowire arrays via electrochemical deposition in a conventional three-electrode cell. Different ways of improving the quality of the obtained films have been studied (working electrode, constant and pulsed potentials, different chemical baths, etc.) in order to obtain highly oriented (110) films, which are the most favorable for out-of-plane applications. Then, nanostructuration has been achieved by changing the working electrode to porous alumina templates and realizing the electrochemical deposition inside the pores. The samples produced have been characterized using SEM, EDX, AFM, XRD, and Raman spectrometry, and in the case of the films, their transport properties have also been measured.Peer Reviewe

Programa de investigación acción participativa: Nueva constitución y procesos constituyentes : ¿Qué constitución tenemos y qué constitución deberíamos tener?

Programa de Investigación Acción Participativa sobre “Nueva Constitución y Procesos Constituyentes” del Centro de Investigación en Derecho Crítico (CiDerCrit) FCJyS (UNLP), la Cátedra Libre del Manifiesto Argentino UNLP, con la participación del Observatorio Electoral y la Cátedra 3 Derecho Político de la FCJyS (UNLP) y otras instancias de la facultad y universidad que se puedan sumar en el futuro.Facultad de Ciencias Jurídicas y Sociale

Programa de investigación acción participativa: Nueva constitución y procesos constituyentes : ¿Qué constitución tenemos y qué constitución deberíamos tener?

Programa de Investigación Acción Participativa sobre “Nueva Constitución y Procesos Constituyentes” del Centro de Investigación en Derecho Crítico (CiDerCrit) FCJyS (UNLP), la Cátedra Libre del Manifiesto Argentino UNLP, con la participación del Observatorio Electoral y la Cátedra 3 Derecho Político de la FCJyS (UNLP) y otras instancias de la facultad y universidad que se puedan sumar en el futuro.Facultad de Ciencias Jurídicas y Sociale

Programa de investigación acción participativa: Nueva constitución y procesos constituyentes : ¿Qué constitución tenemos y qué constitución deberíamos tener?

Programa de Investigación Acción Participativa sobre “Nueva Constitución y Procesos Constituyentes” del Centro de Investigación en Derecho Crítico (CiDerCrit) FCJyS (UNLP), la Cátedra Libre del Manifiesto Argentino UNLP, con la participación del Observatorio Electoral y la Cátedra 3 Derecho Político de la FCJyS (UNLP) y otras instancias de la facultad y universidad que se puedan sumar en el futuro.Facultad de Ciencias Jurídicas y Sociale

The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V

The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Comment: Accepted to ApJ

The eighteenth data release of the Sloan Digital Sky Surveys : targeting and first spectra from SDSS-V

The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Publisher PDFPeer reviewe

Altimetry for the future: Building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide