Evaluación ambiental por medio del análisis de ciclo de vida del relleno sanitario del distrito de Nauta, en Loreto

La generación y tratamiento de los residuos sólidos municipales es un problema con el que ha tenido que lidiar toda civilización desde sus inicios. Desde el siglo XX el manejo y control de ellos se fue perfeccionando a lo largo de Europa de modo que los impactos a la salud humana y al ambiente se vean minimizados. Por ello, se inició la migración del uso de rellenos sanitarios a sistemas de tratamiento más avanzados e integrales, de modo que se pueda optimizar el consumo energético y mejorar el desempeño socio-económico y ambiental de estos. Sin embargo, la realidad al día de hoy en el Perú es muy distante de esto. Actualmente, el país está buscando hacer la transición de la disposición en botaderos informales a rellenos sanitarios, por lo que se están abriendo nuevos emplazamientos a lo largo y ancho del país. Por esto y con el fin de poder identificar los principales impactos ambientales y tomar medidas de mitigación adecuadas, se ha realizado una evaluación ambiental por medio del Análisis de Ciclo de Vida de un relleno sanitario ubicado en la ciudad de Nauta (Loreto), en la selva amazónica. El ciclo de vida del relleno sanitario incluyó las etapas desde la extracción de los materiales, construcción del emplazamiento y operación, hasta el cierre del relleno. La unidad funcional estudiada fue de 1 tonelada de residuos sólidos municipales generados en la ciudad de Nauta y su desempeño a lo largo de 100 años. Se utilizó el software de cálculo especializado en sistemas de tratamiento de residuos sólidos EASETECH para llevar a cabo el modelado del sistema. Se modelaron 5 escenarios: un botadero abierto poco profundo, un botadero abierto profundo, el relleno sanitario actual, en el que no se realiza tratamiento de biogás, y dos escenarios de mejora: uno en el que se realiza combustión del biogás y otro en el que se realiza recuperación de energía. Para evaluar los impactos se emplearon 9 categorías de impacto, siendo 1 de ellas Cambio Climático con el método IPCC 2013 y las restantes del método ReCiPe 2008. Los principales resultados muestran que el impacto total del relleno en la categoría de Cambio Climático asciende a 1376 kg CO2-eq por unidad funcional, y se reduce a 696 y 355 kg CO2-eq si se implementa la quema de biogás y recuperación de energía, respectivamente. Asimismo, la mayor parte de las emisiones se generan a lo largo de los primeros 5 años debido a las condiciones climáticas calurosas y húmedas de la selva amazónica. En cuanto a las categorías de impacto restantes, estas se ven incrementadas en gran medida por las elevadas precipitaciones de la región. Además, la migración de botadero informales a rellenos sanitarios, si bien incrementa el impacto en Cambio Climático, reduce en hasta 4 órdenes de magnitud los impactos en la mayoría de categorías restantes, lo que implicaría definitivamente un beneficio ambiental significativo. Finalmente, se concluye que se deben realizar mejoras en la infraestructura actual y en el manejo del relleno para lograr reducir impactos en eutrofización y toxicidad. De igual manera, para poder reducir el impacto en la categoría de Cambio Climático se deben implementar sistemas de tratamiento de biogás. El Ministerio del Ambiente debe tomar en consideración estos hallazgos para poder mejorar la propuesta de las Contribuciones Nacionales Determinadas ante el Acuerdo de París, para así poder cumplir el compromiso tomado. Esto se debe a que la transición de botaderos abiertos a rellenos sanitarios sin tratamiento de biogás no reduce el potencial de calentamiento global, sino lo incrementa. Por último, se puede afirmar que los resultados de la presente investigación marcan un hito en el rubro de los residuos sólidos y deben formar la base de futuras investigaciones a desarrollar en el país.Tesi

Environmental performance of peruvian waste management systems under a life cycle approach

Peru generated in 2014 a total of 7.5 million metric tons of municipal solid waste (MSW). Of these, 47 % of residues ended up in open dumpsites and only 21 % were sent to controlled landfills. Efforts must be made to conduct a change from open dumpsites to sanitary landfills, reaching an adequate and sustainable waste management system. This study aims at meeting this challenge by means of the Life Cycle Assessment (LCA) methodology. In particular, the objective of this study is to develop a life cycle model that will allow the estimation of environmental impacts linked to waste landfilling in Peru, and to compare in further studies alternatives to determine a more environmentally sustainable solution. The model is flexible in order to be adapted to the three main geo-climatic regions in Peru: the hyper-arid coast, the Andean Highlands and the Amazon Rainforest. The life cycle model was developed with the EASETECH software, taking into account the phases of construction, operation and end-of-life the Peruvian landfills. The main parameters of this model include waste composition and the characteristics and treatment of the leachate and landfill gas, taking into consideration local parameters such as temperature, humidity and precipitation intensity. The model lays the foundation stone to determine the main hotspots in Peruvian sanitary landfills. This information will allow achieving an adequate and sustainable waste management by proposing improvement measures to help stakeholders in the decision-making process

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV

Isolated photon production is measured in proton-proton and lead-lead collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80 GeV with the CMS detector at the LHC. The measured ET spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon ET-differential yields, scaled by the number of incoherent nucleon-nucleon collisions, is consistent with unity for all PbPb reaction centralities.Comment: Submitted to Physics Letters

Search for three-jet resonances in pp Collisions at √s=7 TeV

This article is published Open Access at sciencedirect.com. It is distributed under the terms of the Creative Commons Attribution License 3.0.-- et al.Results are reported from a search for the production of three-jet resonances in pp collisions at a center-of-mass energy √s=7  TeV. The study uses the data sample collected by the CMS experiment at the LHC in 2011, corresponding to an integrated luminosity of 5.0fb -1. Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed for the presence of resonances in the three-jet invariant mass spectrum. No evidence for a narrow resonance is found in the data, and limits are set on the cross section for gluino pair production in an R-parity-violating supersymmetry model, for gluino masses greater than 280 GeV. Assuming a branching fraction for gluino decay into three jets of 100%, gluino masses below 460 GeV are excluded at 95% confidence level. These results significantly extend the range of previous limits. © 2012 CERN.European Commission; Federal Ministry of Science, Research and Economy (Austria); ); Agency for Innovation by Science and Technology (Belgium); Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Brasil); Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro; Fundação de Amparo à Pesquisa do Estado de São Paulo; Ministry of Science and Technology of the People's Republic of China; National Natural Science Foundation of China; Colciencias (Colombia); Ministry of Science, Education and Sports of the Republic of Croatia; Research Promotion Foundation (Cyprus); Centre National de la Recherche Scientifique (France); Bundesministerium für Bildung und Forschung (Deutschland); Deutsche Forschungsgemeinschaft; General Secretariat of Research and Technology (Greece); Helsinki Institute of Physics; National Office for Research and Technology (Hungary); Institute for Research in Fundamental Sciences (Iran); Science Foundation Ireland; Istituto Nazionale di Fisica Nucleare (Italia); Compagnia di San Paolo (Italia); National Research Foundation of Korea; Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (México); Consejo Nacional de Ciencia y Tecnología (México); Secretaría de Educación Pública (México); Universidad Autónoma de San Luis Potosí; Ministry of Science and Innovation (New Zealand); Pakistan Atomic Energy Commission; National Science Center (Poland); Fundação para a Ciência e a Tecnologia (Portugal); Joint Institute for Nuclear Research (Russia); Russian Foundation for Basic Research; Ministry of Education, Science and Technological Development (Serbia); Ministerio de Ciencia e Innovación (España); Swiss National Science Foundation.Peer Reviewe

Search for a Higgs boson in the decay channel H → ZZ(*) → qq̅ l−l+ in pp collisions at √s̅ = 7 TeV

Peer reviewe

Nietzsches gelijk: Waarom wijsheid achteraf onbillijk is

A search is performed for a massive new vector-like quark T, with charge 2/3, that is pair produced together with its antiparticle in proton-proton collisions. The data were collected by the CMS experiment at the Large Hadron Collider in 2012 at sqrt(s) = 8 TeV and correspond to an integrated luminosity of 19.5 inverse femtobarns. The T quark is assumed to decay into three different final states, bW, tZ, and tH. The search is carried out using events with at least one isolated lepton. No deviations from standard model expectations are observed, and lower limits are set on the T quark mass at 95% confidence level. The lower limit lies between 687 and 782 GeV for all possible values of the branching fractions into the three different final states assuming strong production. These limits are the most stringent constraints to date on the existence of such a quark