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Diffusion of Quinine with Ethanol as a Co-Solvent in Supercritical CO2
Get PDFThis study aims at contributing to quinine extraction using supercritical CO2 and ethanol as a co-solvent. The diffusion coefficients of quinine in supercritical CO2 are measured using the Taylor dispersion technique when quinine is pre-dissolved in ethanol. First, the diffusion coefficients of pure ethanol in the supercritical state of CO2 were investigated in order to get a basis for seeing a relative change in the diffusion coefficient with the addition of quinine. We report measurements of the diffusion coefficients of ethanol in scCO2 in the temperature range from 304.3 to 343 K and pressures of 9.5, 10 and 12 MPa. Next, the diffusion coefficients of different amounts of quinine dissolved in ethanol and injected into supercritical CO2 were measured in the same range of temperatures at p = 12 Mpa. At the pressure p = 9.5 MPa, which is close to the critical pressure, the diffusion coefficients were measured at the temperature, T = 343 K, far from the critical value. It was found that the diffusion coefficients are significantly dependent on the amount of quinine in a small range of its content, less than 0.1%. It is quite likely that this behavior is associated with a change in the spatial structure, that is, the formation of clusters or compounds, and a subsequent increase in the molecular weight of the diffusive substance
Eskualduna astekariko kideak eta laguntzaileak
Get PDFDozenaka lagunek parte hartu zuten Eskualduna astekarian, gisa batez edo bestez. Orain
arte agertutako izen zerrendatik harago, ez zen xehetasun handirik kide gehienei buruz. Kide
horien sorterriak, sortegunak, lanak, lantokiak, karguak eta abar bildu dira lan honetan,
laguntzaile bakoitzaren biografia txikia egiteko eta, bereziki, Eskualdunaren argazki xeheagoa
egiteko. Astekariak Ipar Euskal Herri osoan zeuzkan laguntzaileak, eta asko ziren ardura
politikoren bat zutenak.Docenas de hombres y mujeres tomaron parte en el semanal Eskualduna. A parte de los
nombres aparecidos hasta la fecha, no había muchos detalles sobre la mayoría de estas personas.
En este artículo se han recopilado los lugares y fechas de nacimiento, trabajos, lugares
de trabajo, cargos etc. de estas personas, con el fin último de completar la biografiá de dichos
colaboradores y hacer la fotografía de Euskaduna mas definida. Son muchos los colaboradores
que el semanal tenía en el País Vasco Norte, algunos de de los cuales ostentaban a su vez
cargos políticos.Des dizaines d’hommes et de femmes ont collaboré à l’hebdomadaire Eskualduna. Mis à
part les noms de ces collaborateurs, on ne savait pas grand-chose d’eux. Cet article nous
donne leurs lieux et dates de naissance, leurs métiers, lieux de travail, fonctions, afin d’enrichir
leurs biographies et de donner une image plus précise de Eskualduna. Cet hebdomadaire
avait de nombreux collaborateurs en Pays Basque Nord et certains d’entre eux avaient des
responsabilités politiques.Dozens of people took part in the weekly Eskualduna in one way or another. Beyond the
lists of names that have appeared so far, there has been little detail about most of the members
those stakeholders. Their origins, dates, jobs, workplaces, positions, etc. have been gathered
in this work to offer a short biography of each contributor and, in particular, a more
detailed view of Eskualduna. It had supporters from all over the Northern Basque Country,
and many of them had political roles
Near Solidus Forming (NSF): Semi-Solid Steel Forming at High Solid Content to Obtain As-Forged Properties
Get PDFNear solidus forming (NSF) of steels is a novel process under the umbrella of semi-solid forming technologies midway between classical hot forging and semi-solid technologies. This article presents the work done at Mondragon Unibertsitatea to develop this technology and demonstrates the great potential of the NSF process. The study proves the capability of the process to reduce raw material consumption by 20%, reduce forming loads from 2100 t to 300 t, and reduce forming steps from three to one, to obtain as-forged mechanical properties, as well as the excellent repeatability of the process. The work demonstrates that manufacturing commercial steel components in a single step using several off-the-shelf alloys is possible thanks to the flowing pattern of the material, which enables near-net shaping. In the first part of the article, a general overview of the semi-automated near solidus forming cell, together with a description of the NSF manufacturing trials, is provided, followed by the presentation and discussion of the results for the selected steel alloys
A methodology and experimental implementation for industrial robot health assessment via torque signature analysis
Get PDFThis manuscript focuses on methodological and technological advances in the field of health assessment and predictive maintenance for industrial robots. We propose a non-intrusive methodology for industrial robot joint health assessment. Torque sensor data is used to create a digital signature given a defined trajectory and load combination. The signature of each individual robot is later used to diagnose mechanical deterioration. We prove the robustness and reliability of the methodology in a real industrial use case scenario. Then, an in depth mechanical inspection is carried out in order to identify the root cause of the failure diagnosed in this article. The proposed methodology is useful for medium and long term health assessment for industrial robots working in assembly lines, where years of almost uninterrupted work can cause irreversible damage
Implementación de la metodología de diseño para montaje DFA-SPDP en un caso de estudio académico en Mondragon Unibertsitatea
No full textLas metodologías de diseño para el montaje DFA ayudan a los diseñadores a considerar el proceso de montaje de un producto desde las fases iniciales del diseño. Las metodologías DFA más extendidas (Boothroyd-Dewhurst, Hitachi Assemblability method, Lucas) no consideran las tres primeras fases de desarrollo de un producto (especificaciones, diseño conceptual y diseño en detalle) mientras que una nueva metodología denominada DFA-SPDP sí las considera. Esta comunicación tiene como objetivo avanzar en la validación de la metodología DFA-SPDP como metodología que considera las tres fases de desarrollo de producto e inferir las aportaciones que realiza esta metodología respecto a una metodología genérica de diseño. Para ello, se implementa en un caso de estudio académico, la transmisión de una máquina recoge-pelotas. Así, un alumno de Trabajo Fin De Grado de Mondragón Unibertsitatea aplica la metodología DFA-SPDP en el diseño y compara sus resultados con el diseño que un grupo de alumnos de la misma universidad realizó aplicando un proceso genérico sin considerar el montaje de manera específica. La comparación de los resultados muestra que mediante la metodología DFA-SPDP se mejora en un 40% el tiempo de montaje. Además, las características del diseño desarrollado mediante esta metodología impulsan los criterios de Economía Circular
Gazteria eta irratia aro digitalean: nazioarteko praktiken azterketa, euskal gazteen iritziak eta aurrera begirako proposamenak
No full textLan honek Euskal Herriko gazteen musika eta entretenimendu-edukien kontsumoa ikertzen du, euskarazko eskaintzan sumatzen dituzten hutsuneak identifikatzeko asmoz. Lau bide baliatu dira informazioa biltzeko: nazioarteko irrati musikalen programazioaren eduki-analisia, talde-eztabaida Euskal Herriko gazte batzuekin, behaketak Espainia eta Kataluniako hiru irratitan eta elkarrizketak irrati horietako arduradunekin. Informazio horren argitan zortzi ataletan banatutako proposamena landu da Gaztea irratiarentzat, irudiaren aro digitalean Euskal Herriko gazteekin daukan konexioa areagotze aldera
Responsible Innovation for Sustainable Development Goals in Business: An Agenda for Cooperative Firms
Get PDFIn this contribution, we explore the possibilities of Responsible Innovation (RI) to assess and support the engagement of businesses in the spectrum of Social and Solidarity Economy (SSE) and, in particular, cooperatives to the implementation of Sustainable Development Goals (SDGs) at the firm level. We conduct a critical review of the academic literature on sustainable development and responsible innovation, focusing on the role of business to identify how firms in the spectrum of SSE can contribute through responsible innovation to the sustainable development agenda and how firms in the spectrum of SSE can benefit from it. Results suggest that firms can benefit from responsible innovation in the transformation of their business models. On the other hand, firms in the spectrum of SSE contribute to extending the scope of SDGs to business, not focusing on what cooperatives do by their nature (e.g., principles and values), but their contribution to key horizontal enablers (e.g., partnership and innovation) for the integration of firms in the sustainable development agenda. To our knowledge, this is the first time that the relationship between SSE firms and RI is assessed from the perspective of firms’ contribution to SDGs. Further research is needed to sophisticate the translation of particular tools developed in the framework of RI to firms in the spectrum of SSE and, in particular, cooperative firms
On the Role of Contact and System Stiffness in the Measurement of Principal Variables in Fretting Wear Testing
Get PDFIn this work, the role of the contact stiffness in the measurement of principal variables in fretting wear tests is assessed. Several fretting wear tribometers found in the literature, including one developed by the authors, are analysed and modelled using numerical methods. The results show the importance of the tribosystem stiffness and tangential contact stiffness in the displacement sensor calibration and in the correct numerical modelling of fretting wear tests, especially for flat-to-flat contact configuration. The study highlights that, in most cases, direct comparisons between fretting results with severe wear obtained with different tribometers cannot be performed if the contact stiffness is not properly considered during the development of the experiments
Team Emotional Intelligence in Working Contexts: Development and Validation of the Team-Trait Meta Mood Scale (T-TMMS)
Get PDFThe collective construct of Team Emotional Intelligence (TEI) has been widely used and discussed. However, although several studies have examined the relationship
between individual emotional intelligence and transformational leadership, few reports have explored the TEI of leadership teams. The aim of this study was to develop a scale to measure TEI, developing and validating the T-TMMS in a sample of 1,746 participants grouped into 152 leadership teams. The research design of the study was cross-sectional, and, in order to observe reliability as well as the construct, convergent, and predictive validity of the scale, we conducted an internal consistency analysis, confirmatory factor analysis, as well as a correlation and hierarchical linear regression analysis. The T-TMMS showed a three-factor structure (Attention, Clarity, and Repair), with adequate internal consistency, temporal stability, and convergent validity. We also examined the relationship between TEI and organizational performance. The limitations and implications of this new scale for organizational contexts are discussed