Separation of Carbon Dioxide from Nitrogen and Water in Flue Gas Streams

Grand Canonical Monte Carlo simulations (GCMC) are used to examine the adsorption isotherms of carbon dioxide, nitrogen, and water in metal-organic frameworks (MOFs). Molecular Dynamics (MD) simulations are used to determine the diffusion coefficients of carbon dioxide, nitrogen, and water in MOFs. The metal-organic frameworks studied are copper trimesate (Cu-BTC), zinc terephthalate (IRMOF1), and MIL-47, which belongs to the Materials of the Institute Lavoisier series. Diffusion coefficients are determined by the mean-square displacement method derived by Albert Einstein. The diffusion coefficients of each component in the flue gas are analyzed to examine the effect of temperature in diffusion coefficients and study the motion of the gases in the MOF. At thermal equilibrium, the radial distribution function of carbon dioxide, nitrogen, and water are obtained to find the position of atoms with respect to the metal sites of the MOFs. The selectivity for carbon dioxide in a gas mixture composed of carbon dioxide, nitrogen, and water is determined at room temperature. The selectivity for carbon dioxide in flue gas is found by considering the amount adsorbed of carbon dioxide with respect to the amount adsorbed of nitrogen and the molar fractions of carbon dioxide and nitrogen in the flue gas. To account for the molecular interactions between the molecules in the flue gas and the metal-organic frameworks, van der Waals forces are accounted in this study. The Lennard Jones potential parameters for each atom in the metal-organic framework are obtained from the Dreiding force field. Location of carbon dioxide, nitrogen, and water relative to the metal atom in the MOF is observed using Material Studio 5.5 and Visual Molecular Dynamics. Based on the computational results, MIL-47 has the highest selectivity for carbon dioxide in gas mixture at room temperature because carbon dioxide strongly interacts with vanadium metal. Cu-BTC also shows high selectivity for carbon dioxide, whereas IRMOF-1 has lower selectivity for carbon dioxide

La imagen y la narrativa como herramientas para el abordaje psicosocial en escenarios de violencia. Municipios de Palestina, Lérida, Mariquita, Neiva, Pasto, y Cartagena de Indias

La imagen y la narrativa como herramientas para el abordaje psicosocial en escenarios de violencia. Municipios de Palestina, Lérida, Mariquita, Neiva, Pasto, y Cartagena de Indias.El diplomado de “Profundización en Acompañamiento Psicosocial en Escenarios de Violencia”, nos permite fomentar conocimientos, destrezas y competencias para fortalecer nuestra experiencia práctica en atención a las víctimas del conflicto armado. Por medio del enfoque narrativo, permite analizar de manera individual, familiar y social comunitario, todas aquellas experiencias traumáticas como; Desplazamiento, desesperanza, miedo, muertes, violaciones, mutilaciones etc. Así mismo este enfoque narrativo nos aporta herramientas valiosas para trasformar todas aquellas experiencias victimizantes en historias de vida, esperanza, metas y reconciliación, posibilitando la reconstrucción de forma subjetiva a través de la memoria y la narrativa. Mediante el análisis de relatos de violencia, nos permite conocer que muchas de las victimas logran reconstruirse de manera positiva, como es el caso de Carlos Girón, un joven con graves afectaciones físicas y psicológicas a causa de una granada ha logrado fijarse metas y poder seguir adelante. A través de la formulación de preguntas reflexivas, circulares y estrategias, nos permite identificar el proceso clave, al momento de realizar la entrevista a una víctima logrando conectar con su historia, sus emociones y recolectar información valiosa para su acompañamiento psicosocial. También se aborda la comunidad de Cacarica en la que desde nuestro ejercicio profesional brindar estrategias de afrontamiento y promover la autogestión y potenciación comunitaria.The diploma of "Deepening in accompanying psychosocial in scenarios of violence", allows us to promote knowledge, skills and competence to strengthen our practical experience in care to the victims of the armed conflict. Using the narrative approach, allows analysis of individual, family and social community, all those traumatic experiences such as; Displacement, despair, fear, deaths, rapes, mutilations etc. Likewise this narrative approach provides us with valuable tools to transform all those experiences victimizing in stories of life, hope, goals and reconciliation, enabling reconstruction in a subjective way through memory and the narrative. Through the analysis of accounts of violence, lets us know that many of the victims they manage to reconstruct positively, as it is the case of Carlos Girón, a young man with serious physical and psychological damage caused by a grenade has managed to set goals and to be able to move forward. Through the formulation of reflective questions, circulars and strategies, enables us to identify the process key to the time of the interview a victim managing to connect with their history, their emotions and collect valuable information to your psychosocial accompaniment. Also deals with the community of Cacarica in since our practice providing coping strategies and promoting self-management and community empowerment

A Study On The Surface Chemistry Of Lead Chalcogenides Nanocrystals And Patchy Colloidal Particles

We present an implicit-solvent density functional theory study of lead selenide (PbSe) and lead sulfide (PbS) nanocrystal surfaces and investigate the effect of solvation on the adsorption of ligands and the surface energies of PbS and PbSe. We determine the binding energies of ligands in solvent medium on {100}, {110}, and {111} facets of PbS and PbSe using density-functional theory with a polarizable continuum model to describe the solvent. We find that polar solvents significantly reduce the surface energies of PbSe and PbS and the ligand binding energies, whereas nonpolar solvents have negligible effects on surface energies and ligand adsorption. The results explain how polar solvents can be used to remove ligands from nanocrystal facets and provide guidance how to selectively remove ligands from specific surfaces. We also present work on patchy colloidal particles and propose the confinement of nonspherical patchy particles for photonic crystals

Structure and Dynamics of Carbon Dioxide, Nitrogen, Water, and Their Mixtures in Metal Organic Frameworks

The self-diffusion coefficients of carbon dioxide, nitrogen, and water in metal organic frameworks (IRMOF-1, Cu-BTC, and MIL-47) are calculated using molecular dynamics simulations at various temperatures for pure gases and in mixtures. The structure of the adsorbates with respect to the metal active sites in the metal organic frameworks and their intermolecular structural features are investigated through radial distribution functions and related to the self-diffusivity behavior. It is found that while in IRMOF-1 the three species maintain their mobility when they are adsorbed as pure components or in mixtures, the diffusivities of CO₂ and water in Cu-BTC are <i>slower</i> in the ternary mixture than when adsorbed individually, whereas the opposite behavior is observed in MIL-47 where the species diffuse <i>faster</i> in the mixture than as pure components. The behavior can be explained in terms of the strong interactions of water with the framework which slows down diffusion in Cu-BTC; however in MIL-47, the competition between CO₂ and water for the active vanadium sites increases the mobilities of both adsorbates

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population