DArKSIDE-50: A view of the first atmospheric argon run

The DArKside (DS) program aims to detect the so-called WIMPs (Weakly Interactive Massive Particle) which are considered the best candidates for Dark Matter. WIMPs elastically scattering would be detected by using a twophase Time Projection Chamber (TPC) based on argon nuclei target. Thanks to the properties of the scintillation and ionization signals detected by the TPC it is possible to discriminate a WIMP-induced signal from one induced by background. DS-50 started its data taking on November 2013 with atmospheric argon (later with underground argon depleted in 39Ar.

A ‘revision’ of Antonio Caro’s formative period : 1970—1976

textThis thesis will examine the conceptual strategies articulated by a corpus of six works created within the first seven years of Colombian conceptual artist Antonio Caro’s career (1970-1976.) The works—Cabeza de Lleras (1970) [Head of Lleras], Aqui no cabe el arte (1972) [Art Does Not Fit Here], Manuel Quintín Lame información y variación visual (1972) [Manuel Quintín Lame, Information and Visual Variation], El imperialismo es un tigre de papel (1973) [Imperialism is a Paper Tiger], Colombia—Marlboro (1973-1975), and Colombia—Coca-Cola (1976)—despite stressing dematerialization, displaying simple designs, and communicating concise messages addressing political and cultural issues that are tied to a historical and geographic specificity, have been repeated until acquiring an iconic status. As a crucial tactic that is central to Caro’s work, this thesis will analyze both the advantages and disadvantages inherent in the strategy of repetition and how these have altered or enhanced the meaning of the works through time. Furthermore, five out of the six works in question employ text in a very particular way that results from Caro’s keen awareness of the visual potential of words. Likewise, they display anti-conventionalisms particularly with regards to the implementation of informal procedures (i.e. photocopying, posters, art actions, etc…) and the utilization of precarious materials (i.e. salt) that are often charged with historical meanings; the inherent short-lived nature of the materials used by Caro also points to the ephemeral quality of his production and to the rejection of the notion of art as a commodity. Finally, the works enact institutional critique on two fronts: they criticize the art institution from within, while simultaneously denouncing the politics of the state apparatus and the hegemonic values imposed by the dominant sectors of society. All in all, the salient features present in these six works point to Caro’s commitment to his environment while also contributing to the development of contemporary Colombian art.Art Histor

Synthesis and electrical characterization of graphene nanowalls electrodes

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2021, Tutors: Enric Bertran Serra, Roger Amade RoviraThe aim of this project is to study the electrochemical properties of manufactured electrodes based on graphene nanowalls (GNWs) grown on stainless steel (SS310) by inductively coupled plasma vapor deposition (ICP-CVD). In order to improve the electrochemical characteristics of the electrode, a Mn-oxide/GNWs/SS310 system was deposited by magnetron sputtering (MS) from a target of MnO2. The morphology of GNWs electrode and the electrode decorated by Mn-oxide was evidenced by electronic microscopy. In addition, the samples were characterized electrochemically by cyclic voltammetry (CV) and galvanometric charge-discharge cycles (CDG). As a result, a specific capacitance of 0.21 mF/cm2 was obtained on the GNWs/SS310 electrode and 1.74 mF/cm2 on the MnO2/GNWs/SS310 electrod

Pore evolution in interstellar ice analogues: simulating the effects of temperature increase

Context. The level of porosity of interstellar ices - largely comprised of amorphous solid water (ASW) - contains clues on the trapping capacity of other volatile species and determines the surface accessibility that is needed for solid state reactions to take place. Aims. Our goal is to simulate the growth of amorphous water ice at low temperature (10 K) and to characterize the evolution of the porosity (and the specific surface area) as a function of temperature (from 10 to 120 K). Methods. Kinetic Monte Carlo simulations are used to mimic the formation and the thermal evolution of pores in amorphous water ice. We follow the accretion of gas-phase water molecules as well as their migration on surfaces with different grid sizes, both at the top growing layer and within the bulk. Results. We show that the porosity characteristics change substantially in water ice as the temperature increases. The total surface of the pores decreases strongly while the total volume decreases only slightly for higher temperatures. This will decrease the overall reaction efficiency, but in parallel, small pores connect and merge, allowing trapped molecules to meet and react within the pores network, providing a pathway to increase the reaction efficiency. We introduce pore coalescence as a new solid state process that may boost the solid state formation of new molecules in space and has not been considered so far.Comment: 9 pages, 8 figures Accepted for publication in A&

Multi-scale modeling of sediment and nutrient flow dynamics in the Ouémé catchment (Benin) - towards an assessment of global change effects on soil degradation and water quality

Beyond aspects such as the quantification of soil and water degradation, this work investigated impacts of differences in the input boundary conditions (e.g. soil map, land use) on the performance of the Soil and Water Assessment Tool (SWAT). Effects of different local crop management scenarios (e.g. fertilizer input) on the simulation of plant growth and soil nutrient load to surface water and groundwater systems were also evaluated. The study was carried out in the Ouémé catchment (49,256 km²) at the outlet of Bonou in Bénin, where different sub-catchments were extensively investigated. Therefore, three different soil maps have been used: two maps of the hierarchical Soil and Terrain digital database approach (SOTER) and the soil mapping at the reconnaissance level, with one dominant soil type per mapping unit approach (ORSTOM); all three were available at the same resolution. The mapping approach’s impact on the model results was within the same magnitude of that of maps with different resolutions but developed with the same mapping approach. While the latter aspect is often studied, the first one is usually neglected. A land use map was refined for the study area, enabling the evaluation of four management scenarios: fertilizer supplied only to cotton, rice and maize, as is common in Benin (Sc0); crop systems without the use of fertilizer (Sc0a); similar fertilizer inputs to all cropping systems (Sc1); and the original land use map without fertilizer inputs (Sc1a). Compared to the first scenario, the latter two scenarios, commonly used in regional scale modeling, exhibited distinct biases in plant growth parameters, crop yields, water yield, sediment yield and nitrogen load. A regionalization methodology has been developed and applied to derive scale dependent regression-based parameter models, using catchment physical properties depending on spatial scale as explanatory variables for SWAT model parameters obtained from multi-scale investigations, for accurately simulating water-sediment-nutrient fluxes at ungauged and large scale basins. With respect to process representation in the SWAT model, it was found that in the Ouémé catchment, geology appears to be a major driver of hydrological response, correlating significantly with eleven out of fifteen model parameters. Slope appears to be powerful to control the channel conductivity, groundwater threshold for base flow generation and soil evaporation compensation (accounting for capillary, crusting and cracking actions). The soil type lixisol, which is a dominant soil component within the Ouémé catchment, partly explained the surface runoff lag and the maximum retrained sediment. The occurrence of lateritic consolidated soil layer explained the soil susceptibility to erosion and drainage density explained the fraction of aquifer percolation. Parameters such as the curve number, controlling the surface runoff were not consistently explained by the catchment properties, leading to a slightly overestimation of runoff peaks, probably due to the non-uniqueness of the considered calibrated parameter set. These relationships were successfully used to compute daily runoff hydrographs (Model efficiency ranged from 0.61 to 0.67 and coefficient of determination of roughly 0.70) at different catchment scales (from 1179 km2 to 23488 km2). By adopting this methodology two difficulties in model setup in the Ouémé catchment were overcome: parameter scale-effects and associated uncertainty issues for large scale model application and the lack and non-accurateness of boundary condition data (e.g. stream water-sediment-nutrient measurements). Climate and land use change impacts on the ongoing land and water degradation were compared at different spatial scales (Donga-Pont: 586 km2; Ouémé-Bonou: about 49,256 km2). Surface runoff, groundwater flow, sediment and organic nitrogen loads were dominantly affected by land use change of -8 to +50%, while water yield and evapotranspiration were dominantly affected by climate change of -31 to +2%. It was found that variables such as surface runoff, groundwater flow, sediment and transported nutrients, mainly sensitive to land use change were significantly affected by the increasing scale, while variables such as water yield and evapotranspiration, mainly sensitive to climate change, have changed almost similarly for the both scales

Propuesta para la gestión integral de residuos eléctricos y electrónicos (Raee) en la administración municipal de Chía- Cundinamarca

Presentar una propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE) en la administración municipal de Chía Cundinamarca durante el segundo semestre del 2018Las inadecuadas condiciones y mecanismos de tratamiento para los residuos eléctricos y electrónicos (RAEE) en la administración municipal de chía, Cundinamarca, me llevaron a plantear una propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE), que busca ante todo evitar que se continúe enviando a relleno sanitario desechos que pueden ser reutilizados para otros procesos y dispuesto de otra manera más efectiva. La metodología desarrollada se centra en el marco lógico ya que está definido como un proyecto social y es de gran utilidad para el logro de esta propuesta investigativa. Dentro de las conclusiones se propone que Chía, podría ser un municipio pionero en la creación de una planta de tratamiento de RAEE, donde ganaría por ambas partes, ya que las partes funcionales, se podrían exportar generando grandes recursos financieros y con los materiales plásticos y vidrio, se podría llegar por medio de un tratamiento de fundición a obtener un tipo de asfalto de excelente calidad y durabilidad con lo cual podría realizar el arreglo y mantenimiento de la malla vial de todo el municipio. También se debe gestionar canastas para su clasificación y recolección de residuos tipo RAEE con la empresa Eco-computo, con la que actualmente existe un convenio de tal forma que se cierre la brecha de no tener donde colocarlos cuando para ellos ya no es útil y evitar la disposición en la caneca de Basura. Se sugiere implementar un programa de capacitaciones de tal manera que se sensibilice a todos los funcionarios de la administración de las consecuencias de enviar a relleno sanitario elementos eléctricos y electrónicos y la afectación al medio ambiente

Propuesta para la gestión integral de residuos eléctricos y electrónicos (Raee) en la administración municipal de Chía- Cundinamarca

Presentar una propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE) en la administración municipal de Chía Cundinamarca durante el segundo semestre del 2018Las inadecuadas condiciones y mecanismos de tratamiento para los residuos eléctricos y electrónicos (RAEE) en la administración municipal de chía, Cundinamarca, me llevaron a plantear una propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE), que busca ante todo evitar que se continúe enviando a relleno sanitario desechos que pueden ser reutilizados para otros procesos y dispuesto de otra manera más efectiva. La metodología desarrollada se centra en el marco lógico ya que está definido como un proyecto social y es de gran utilidad para el logro de esta propuesta investigativa. Dentro de las conclusiones se propone que Chía, podría ser un municipio pionero en la creación de una planta de tratamiento de RAEE, donde ganaría por ambas partes, ya que las partes funcionales, se podrían exportar generando grandes recursos financieros y con los materiales plásticos y vidrio, se podría llegar por medio de un tratamiento de fundición a obtener un tipo de asfalto de excelente calidad y durabilidad con lo cual podría realizar el arreglo y mantenimiento de la malla vial de todo el municipio. También se debe gestionar canastas para su clasificación y recolección de residuos tipo RAEE con la empresa Eco-computo, con la que actualmente existe un convenio de tal forma que se cierre la brecha de no tener donde colocarlos cuando para ellos ya no es útil y evitar la disposición en la caneca de Basura. Se sugiere implementar un programa de capacitaciones de tal manera que se sensibilice a todos los funcionarios de la administración de las consecuencias de enviar a relleno sanitario elementos eléctricos y electrónicos y la afectación al medio ambiente

Propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE) en la administración municipal de Chía- Cundinamarca.

Presentar una propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE) en la administración municipal de Chía Cundinamarca durante el segundo semestre del 2018.Las inadecuadas condiciones y mecanismos de tratamiento para los residuos eléctricos y electrónicos (RAEE) en la administración municipal de chía, Cundinamarca, me llevaron a plantear una propuesta para la gestión integral de residuos eléctricos y electrónicos (RAEE), que busca ante todo evitar que se continúe enviando a relleno sanitario desechos que pueden ser reutilizados para otros procesos y dispuesto de otra manera más efectiva