57 research outputs found

    Termodinámica - Notas de clase

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    Estos apuntes son una recopilación de notas de clase de la asignatura de Termodinámica; incluyen además en cada tema algunos problemas resueltos, bastantes de exámenes anteriores. La función de estas notas es servir de apoyo al estudio de la asignatura, pero en ningún caso pretenden sustituir el uso de libros de texto. Son fruto de varios años de docencia de esta asignatura en la Escuela de Ingenieros de San Sebastián, de la Universidad de Navarra

    Steam oxidation of ferritic steels : kinetics and microstructure

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    The ferritic 2.25Cr–1Mo steel has been subjected to isothermal and non-isothermal oxidation treatments in water steam at several temperatures ranging from 550 to 700 °C for up to 56 days. Under isothermal conditions this steel follows a parabolic oxidation kinetics, with an activation energy of 324 kJ mol –1 . This value corresponds to an apparent activation energy for the global process, which includes both outward diffusion of Fe cations and inward diffusion of oxygen. The oxidation products present in the oxide scales, which were characterised by X-ray diffraction and SEM, are in total agre - ement with the Fe-O phase diagram. Thus, magnetite is the most stable oxide at low temperatures and wustite starts to form above 570 °C. Further studies of the effect of cooling rate have shown that wustite formed at 700 °C transforms into magne - tite during a slow cooling, whereas a rapid cooling inhibits this transformation to a certain extent. For non-isothermal oxidation treatments consisting of a holding period at 550 °C followed by a single or double 4 hours exposure at 700 °C, the oxidation process seems to occur in sequence, thus presenting an additive effect of the oxidation treatments carried out at each temperature. This effect was observed both, for the type of oxide grown, and for the kinetics of the process. Microscopic observations of the oxide scales formed after the various oxidation treatments revealed that the oxide scales are constituted by sublayers of distinct microstructure and chemical composition changing from their surface to the substrate interface

    Comparative analysis of heat dissipation panels for a hybrid cooling system integrated in buildings

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    The use of cooling panels as heat dissipation elements integrated in buildings has been previously investigated by the authors. Those elements would be connected to the condenser and would dissipate the heat in a passive form. Following the research, this study analyses and compares the thermal performance of two heat dissipation panels as part of a hybrid cooling system. Both panels were experimentally tested under different variables, thus having nine scenarios for each panel. Additionally, an already validated model was applied. The empirical results show a considerable difference between the cooling capacity among them, doubling the daily average ratio in one scenario. The heat dissipation ratios vary between 106 and 227 W/m2 in the first case and 140 and 413 W/m2 in the second. Regarding the model applicability, the average error for each panel was 4.0% and 8.5%. The bond between the metal sheet and the pipes of the panels has proven to be the main parameter to assure the highest heat dissipation potential of each panel

    Changes in individual and contextual socio-economic level influence on reproductive behavior in Spanish women in the MCC-Spain study

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    Background The association between socioeconomic level and reproductive factors has been widely studied. For example, it is well known that women with lower socioeconomic status (SES) tend to have more children, the age at first-born being earlier. However, less is known about to what extent the great socioeconomic changes occurred in a country (Spain) could modify women reproductive factors. The main purpose of this article is to analyze the influence of individual and contextual socioeconomic levels on reproductive factors in Spanish women, and to explore whether this influence has changed over the last decades. Methods We performed a cross-sectional design using data from 2038 women recruited as population-based controls in an MCC-Spain case-control study. Results Higher parent’s economic level, education level, occupational level and lower urban vulnerability were associated with higher age at first delivery and lower number of pregnancies. These associations were stronger for women born after 1950: women with unfinished primary education had their first delivery 6 years before women with high education if they were born after 1950 (23.4 vs. 29.8 years) but only 3 years before if they were born before 1950 (25.7 vs. 28.0 years). For women born after 1950, the number of pregnancies dropped from 2.1 (unfinished primary school) to 1.7 (high education), whereas it remained almost unchanged in women born before 1950. Conclusions Reproductive behavior was associated with both individual and area-level socio-economic indicators. Such association was stronger for women born after 1950 regarding age at first delivery and number of pregnancies and for women born before 1950 regarding consumption of hormonal contraceptives or postmenopausal therapy

    Social mobility and healthy behaviours from a gender perspective in the Spanish multicase-control study (MCC-Spain)

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    There is evidence for the influence of socioeconomic status (SES) on healthy behaviours but the effect of social mobility (SM) is not yet well known. This study aims to analyse the influence of origin and destination SES (O-SES and D-SES) and SM on healthy behaviours and co-occurrence, from an integrated gender and age perspective. Data were obtained from the controls of MCC-Spain between 2008-2013 (3,606 participants). Healthy behaviours considered: healthy diet, moderate alcohol consumption, non-smoking and physical activity. SM was categorized as stable high, upward, stable medium, downward or stable low. Binary and multinomial logistic regression models were adjusted. Those aged <65, with a low O-SES, D-SES and stable low SM are less likely to have healthy behaviours in the case of both women (physically active: OR = 0.65 CI = 0.45-0.94, OR = 0.71 CI = 0.52-0.98, OR = 0.61 CI = 0.41-0.91) and men (non-smokers: OR = 0.44 CI = 0.26-0.76, OR = 0.54 CI = 0.35-0.83, OR = 0.41 CI 0.24-0.72; physically active: OR = 0.57 CI = 0.35-0.92, OR = 0.64 CI = 0.44-0.95, OR = 0.53 CI = 0.23-0.87). However, for those aged ≥65, this probability is higher in women with a low O-SES and D-SES (non-smoker: OR = 8.09 CI = 4.18-15.67, OR = 4.14 CI = 2.28-7.52; moderate alcohol consumption: OR = 3.00 CI = 1.45-6.24, OR = 2.83 CI = 1.49-5.37) and in men with a stable low SM (physically active: OR = 1.52 CI = 1.02-1.26). In the case of men, the same behaviour pattern is observed in those with a low O-SES as those with upward mobility, with a higher probability of co-occurring behaviours (three-to-four behaviours: OR = 2.00 CI = 1.22-3.29; OR = 3.13 CI = 1.31-7.48). The relationship of O-SES, D-SES and SM with healthy behaviours is complex and differs according to age and gender.This research was supported by the “Acción Transversal del Cancer”, approved by the Spanish Council of Ministers on 11th October 2007, by the Instituto de Salud Carlos III-FEDER [grant number:PI08/1770, PI08/0533, PI08/1359, PS09/00773-Cantabria, PS09/01286-León, PS09/01903-Valencia, PS09/02078-Huelva, PS09/ 01662-Granada, PI11/01403, PI11/01889-FEDER, PI11/00226, PI11/01810, PI11/02213, PI12/00488, PI12/00265, PI12/01270, PI12/00715, PI12/00150, PI14/01219, PI14/0613, PI15/00069, PI15/00914, PI15/01032, PI11/01810, PI14/01219, PI11/02213, PIE16/00049, PI17/01179, PI17-00092], by the Fundación Marqués de Valdecilla [grant number: API 10/09], by the ICGC International Cancer Genome Consortium CLL (The ICGC CLL-Genome Project is funded by Spanish Ministerio de Economía y Competitividad (MINECO) through the Instituto de Salud Carlos III (ISCIII)), by the Red Temática de Investigación del Cáncer (RTICC) del ISCIII [grant number: RD12/0036/0036], by the Junta de Castilla y León [grant number: LE22A10-2], by the Consejería de Salud of the Junta de Andalucía [grant number: PI-0571-2009, PI-0306-2011, salud201200057018tra], by the Conselleria de Sanitat of the Generalitat Valenciana [grant number: AP_061/10], by the Recercaixa [grant number: 2010ACUP00310], by the Regional Government of the Basque Country, by the Consejería de Sanidad de la Región de Murcia, by the European Commission [grant number: FOOD-CT-2006-036224-HIWATE], by the Spanish Association Against Cancer (AECC) Scientific Foundation [grant number: GCTRA18022MORE], by the Catalan Government-Agency for Management of University and Research Grants (AGAUR) [grant number: 2014SGR647, 2014SGR850 and 2017SGR723], by the Fundación Caja de Ahorros de Asturias and by the University of Oviedo. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.S

    Fine-mapping of prostate cancer susceptibility loci in a large meta-analysis identifies candidate causal variants

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    Prostate cancer is a polygenic disease with a large heritable component. A number of common, low-penetrance prostate cancer risk loci have been identified through GWAS. Here we apply the Bayesian multivariate variable selection algorithm JAM to fine-map 84 prostate cancer susceptibility loci, using summary data from a large European ancestry meta-analysis. We observe evidence for multiple independent signals at 12 regions and 99 risk signals overall. Only 15 original GWAS tag SNPs remain among the catalogue of candidate variants identified; the remainder are replaced by more likely candidates. Biological annotation of our credible set of variants indicates significant enrichment within promoter and enhancer elements, and transcription factor-binding sites, including AR, ERG and FOXA1. In 40 regions at least one variant is colocalised with an eQTL in prostate cancer tissue. The refined set of candidate variants substantially increase the proportion of familial relative risk explained by these known susceptibility regions, which highlights the importance of fine-mapping studies and has implications for clinical risk profiling. © 2018 The Author(s).Prostate cancer is a polygenic disease with a large heritable component. A number of common, low-penetrance prostate cancer risk loci have been identified through GWAS. Here we apply the Bayesian multivariate variable selection algorithm JAM to fine-map 84 prostate cancer susceptibility loci, using summary data from a large European ancestry meta-analysis. We observe evidence for multiple independent signals at 12 regions and 99 risk signals overall. Only 15 original GWAS tag SNPs remain among the catalogue of candidate variants identified; the remainder are replaced by more likely candidates. Biological annotation of our credible set of variants indicates significant enrichment within promoter and enhancer elements, and transcription factor-binding sites, including AR, ERG and FOXA1. In 40 regions at least one variant is colocalised with an eQTL in prostate cancer tissue. The refined set of candidate variants substantially increase the proportion of familial relative risk explained by these known susceptibility regions, which highlights the importance of fine-mapping studies and has implications for clinical risk profiling. © 2018 The Author(s).Peer reviewe

    Examen Termodinámica julio 2009

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    Examen final Termodinámica, convocatoria extraordinaria curso 2008-200

    Examen Termodinámica julio 2009

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    Examen final Termodinámica, convocatoria extraordinaria curso 2008-200

    Examen Termodinámica enero 2009

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    Examen final Termodinámic

    Cuaderno de Tablas y Diagramas de Termodinámica

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    Tablas y diagramas de propiedades termodinámicas de algunos fluidos de interés técnico: gases ideales, agua, fluidos refrigerantes, aire húmedo, etc. Se acompaña de algunas tablas auxiliares (Sistema Internacional de unidades, factores de conversión, sistema periódico de los elementos), y un manual rápido del progama EES (Engineering Equation Solver)
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