255 research outputs found

    Transmission of Helium through Graphynes Pores: First Principles Calculations and Quantum Mechanical Simulations

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    AMOC 2015, Anharmonicity in médium-sized molecules and cluster, CSIC, Madrid (Spain), 26-30 April 2015; http://tct1.iem.csic.es/AMOC2015.htmPeer Reviewe

    Industrialización de la riqueza vegetal: oportunidades sociales y económicas

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    Las empresas enfrentan un importante desafío es esta economía globalizada, porque para sobrevivir tienen que ofrecer nuevos productos con valor agregado en los mercados internacionales. Para ello se requieren profesionales entrenados en las metodologías para el desarrollo de nuevos productos (DNP), y los egresados universitarios tienen que tener estas habilidades para que puedan contribuir a enfrentar esta situación. J unto con esto se requieren también productos innovadores de la mano con la conservación del medio ambiente y aprovechando al máximo los recursos disponibles, bien sea de la tierra o de transformación tecnológica. Con este proyecto se pretende abrir una ventana de oportunidad para que los alumnos del programa de Ingeniería de Procesos puedan adquirir el entrenamiento necesario para desempeñarse con éxito en el DNP. A demás, los empresarios del campo puedan obtener un valor agregado para sus productos como alternativa en tiempos de precios desfavorables.Companies face a major challenge is this globalized economy, because to survive they have to offer new products with added value in the international market. This requires professionals trained in the methodologies for the development of new products (DNP) and university graduates must have these skills so that they can contribute to deal with this situation. A long with this they also require innovations running by the side of conservation of the environment and the taking of full advantage of available resources, either from land or technological transformation. This project is to open a window of opportunity so that the Process Engineering students can acquire the knowledge needed to perform successfully in the DNP training. A lso field employers can get valueadded products as an alternative in times of unfavourable prices

    Notas biológicas y reproductivas sobre el “Chicaguastle” Stenostomum aromaticum (Rubiaceae) árbol en peligro de extinción y endémico de México

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    El árbol Stenostomum aromaticum es conocido por los pobladores como Chicahuastle. Es una especie con distribución geográfica muy restringida y donde los registros de herbario y muestreos de campo la ubican como endémica de México. Por conteos recientes, se conoce que el número de ejemplares de este árbol es de alrededor de 500 individuos entre juveniles y adultos. A pesar de estos datos tan críticos para la especie, no se encuentra en la Norma Oficial Mexicana – SEMARNAT – 2010 pero si en la lista roja de plantas en peligro de extinción de la Unión Internacional para la Conservación de la Naturaleza. Por lo anterior, el objetivo de estas notas fue aportar más conocimiento sobre la biología y ecología de esta especie y sobre su reproducción asexual como estrategia conservacionista para la propagación rápida de individuos.

    Promoting FAIRness in marine data at Centro Nacional Instituto Español de Oceanografía

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    The Spanish Institute of Oceanography is responsible, among other aspects, for scienti c and technical advice for the Government's sheries policy as well as for the protection and sustainability of the marine environment. In this task, it generates a large amount of oceanographic data characterized by its spatial dispersion during acquisition as well as by its di erent typology. The purpose of both the National Oceanographic Data Center and the GIS team is to safeguard data and to disclose what data exists and where, how and when it has been acquired and, in addition, to provide access to that data through the collaboration with di erent international data infrastructures like EMODnet or SeaDataNet. To this end, the data and metadata are subjected to quality control and formatted for integration into a national Spatial Data Infrastructure (SDI). This SDI has a GeoNetwork catalogue with ~ 1750 oceanographic campaigns, together with (meta)data and services that are continuously being revised and incorporated. All this with the ultimate goal of making the data increasingly FAIR

    Transmission of light in deep sea water at the site of the ANTARES neutrino telescope

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    The ANTARES neutrino telescope is a large photomultiplier array designed to detect neutrino-induced upward-going muons by their Cherenkov radiation. Understanding the absorption and scattering of light in the deep Mediterranean is fundamental to optimising the design and performance of the detector. This paper presents measurements of blue and UV light transmission at the ANTARES site taken between 1997 and 2000. The derived values for the scattering length and the angular distribution of particulate scattering were found to be highly correlated, and results are therefore presented in terms of an absorption length;,ab, and an effective scattering length lambda(sct)(eff). The values for blue (UV) light are found to be lambda(abs) similar or equal to 60(26) m, lambda(sct)(eff similar or equal to) 265(122) m, with significant (similar to15%) time variability. Finally, the results of ANTARES simulations showing the effect of these water properties on the anticipated performance of the detector are presented

    Morphological, Electrical, and Chemical Characteristics of Poly(sodium 4-styrenesulfonate) Coated PVDF Ultrafiltration Membranes after Plasma Treatment

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    A commercial ultrafiltration (UF) membrane (HFM-183 de Koch Membrane Systems) made of poly(vinylidene fluoride) (PVDF), was recovered with a negatively-charged polyelectrolyte (poly(sodium 4-styrenesulfonate)) (PSS), and the effects on its electric, chemical, and morphological properties were analyzed. Atomic force microscopy (AFM), liquid-liquid displacement porometry, Electrical Impedance Spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy were used to investigate the modifications induced by the deposition of PSS on the PVDF positively-charged membrane and after its treatment by a radio frequency Ar-plasma. These techniques confirmed a real deposition and posterior compaction of PSS with increasing roughness and decreasing pore sizes. The evolution of the electric resistances of the membranes confirmed crosslinking and compaction with shielding of the sulfonated groups from PSS. In this way, a membrane with a negatively-charged active layer and a pore size which was 60% lower than the original membrane was obtained. The composition of the additive used by manufacturers to modify PVDF to make it positively charged was obtained by different procedures, all of which depended upon the results of X-ray photoelectron spectroscopy, leading to fairly consistent results. This polymer, carrying positive charges, contains quaternary nitrogen, as confirmed by XPS. Moreover, Raman spectroscopy confirmed that PVDF changes from mostly the β to the α phase, which is more stable as a substrate for the deposited PSS. The aim of the tested modifications was to increase the retention of divalent anions without reducing permeability.Fil: Sandoval Olvera, Ivette G.. Universidad de Guanajuato; MéxicoFil: González Muñoz, Pilar. Universidad de Guanajuato; MéxicoFil: Diaz, Dario Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; ArgentinaFil: Maroto Valiente, Ángel. Universidad de Guanajuato; MéxicoFil: Ochoa, Nelio Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; ArgentinaFil: Carmona, Francisco J.. Universidad de Extremadura; EspañaFil: Palacio, Laura. Universidad de Valladolid. Facultad de Ciencias; EspañaFil: Calvo, José I.. Universidad de Valladolid. Facultad de Ciencias; EspañaFil: Hernández, Antonio. Universidad de Valladolid. Facultad de Ciencias; EspañaFil: Ávila Rodríguez, Mario. Universidad de Guanajuato; MéxicoFil: Prádanos, Pedro. Universidad de Valladolid. Facultad de Ciencias; Españ

    Fertilidad y producción de caña de azúcar en Hueyapan De Ocampo, Veracruz, México

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    Se analizaron las principales características químicas para determinar el estado de fertilidad de los suelos tipo Andosol, Vertisol y Gleysol, donde se establece el sistema productivo caña de azúcar en Zapoapan de Amapan perteneciente al municipio de Hueyapan de Ocampo del estado de Veracruz. La importancia de este trabajo radica en ubicar la situación que origina rendimientos muy por debajo de lo que se específica para México. El objetivo del presente trabajo fue evaluar los parámetros pH, materia orgánica, conductividad eléctrica, nitrógeno inorgánico, fósforo, contenidos de potasio, calcio, magnesio, fierro, cobre, manganeso, boro y densidad aparente, siguiendo los métodos establecidos en la NOM-021-RECNAT-2000, para ubicar el estado de fertilidad de los suelos y los posibles impactos ambientales ejercidos sobre este recurso natural. Los resultados mostraron que los suelos andosoles tuvieron las mejores condiciones de fertilidad para el cultivo de caña de azúcar; en tanto que los suelos tipo vertisol mostraron problemas leves de contaminación por los contenidos de boro obtenidos. La materia orgánica y el nitrógeno inorgánico son las variables que se deben atender para mejorar la fertilidad de los suelos. La producción de caña de azúcar en la comunidad de Zapoapan de Amapan, es baja (de 25 a 50 ton hectárea), por lo que se recomienda mejorar las prácticas agrícolas con el fin de incrementar los contenidos de nutrimentos en los tres tipos de suelo

    Cost-effectiveness of multicomponent interventions in type 2 diabetes mellitus in a cluster randomised controlled trial: the INDICA study

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    Objective: To analyse the cost-effectiveness of multicomponent interventions designed to improve outcomes in type 2 diabetes mellitus (T2DM) in primary care in the Canary Islands, Spain, within the INDICA randomised clinical trial, from the public health system perspective. Design: An economic evaluation was conducted for the within-trial period (2 years) comparing the four arms of the INDICA study. Setting: Primary care in the Canary Islands, Spain. Participants: 2334 patients with T2DM without complications were included. Interventions: Interventions for patients (PTI), for primary care professionals (PFI), for both (combined intervention arm for patients and professionals, CBI) and usual care (UC) as a control group. Outcomes: The main outcome was the incremental cost per quality-adjusted life-years (QALY). Only the intervention and the healthcare costs were included. Analysis: Multilevel models were used to estimate results, and to measure the size and significance of incremental changes. Missed values were treated by means of multiple imputations procedure. Results: There were no differences between arms in terms of costs (p=0.093), while some differences were observed in terms of QALYs after 2 years of follow-up (p=0.028). PFI and CBI arms were dominated by the other two arms, PTI and UC. The differences between the PTI and the UC arms were very small in terms of QALYs, but significant in terms of healthcare costs (p=0.045). The total cost of the PTI arm (€2571, 95% CI €2317 to €2826) was lower than the cost in the UC arm (€2750, 95% CI €2506 to €2995), but this difference did not reach statistical significance. Base case estimates of the incremental cost per QALY indicate that the PTI strategy was the cost-effective option. Conclusions: The INDICA intervention designed for patients with T2DM and families is likely to be cost-effective from the public healthcare perspective. A cost-effectiveness model should explore this in the long term.This study received financial support from the Spanish Ministry of Economy, Industry and Competitiveness (Instituto de Salud Carlos III), grants: ADE10/00032 and PI16/00769, jointly funded by the European Regional Development Fund (FEDER) ‘A way to make Europe’. The sponsor did not play any role in study design, collection, analysis and interpretation of data, drawing up of the report or the decision to submit the article for publication.S

    Further progress in the study of epsilon iron oxide in archaeological baked clays

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    [EN] The occurrence of ε-FeO in archaeological samples that have been subjected to high temperatures is gradually being detected by the use of micrometric structural characterization techniques. This work provides new information by revealing that the ε-FeO is formed as a response to temperature, the aggregation state and the position within the baked clay with respect to the nearest heat source. In addition, depending mainly on the atmospheric environment, the temperature reached by the combustion structure, the distance from the heating source and the particle aggregation, other iron oxide magnetic phases are produced. In the baked clay studied here, hematite is found over the whole range of samples studied but its magnetic contribution is negligible. Magnetite is observed at the sample surface, probably due to local atmospheric environment closest to the combustion source. Maghemite is found at all depths up to 6 cm below the sample surface. ε-FeO has a limited distribution, found within 2–3 cm of the sample surface. Furthermore, the viability of this compound as a palaeofield marker has been evaluated in both archaeological and synthetic samples. The results indicate that ε-FeO is able to register the direction of the magnetic field. Linear palaeointensity plots have been obtained in synthetic samples, although the value of the palaeofield could be, sometimes, overestimated.The authors also acknowledge the financial support from the Spanish Ministry of Science, Innovation and Universities under the projects RTI2018-095856-B-C21, CGL2017-87015-P, CGL2017-92285-EXP, CGL2017-92285-EXP/BTE, MAT2017-86540-C4-1-R, MAT2017-87072-C4-2-P and RTI2018-095303-A-C52, from Comunidad de Madrid NANOFRONTMAG S2013/MIT-2850 and NANOMAGCOST S2018/NMT-4321, and from the European Commission under H2020 frame by AMPHIBIAN Project ID: 720853. APO thanks the Ministry of Economy, Industry and Competitiveness (PTA Contract).Peer reviewe

    Accretion-related properties of Herbig Ae/Be stars. Comparison with T Tauris

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    We look for trends relating the mass accretion rate (Macc) and the stellar ages (t), spectral energy distributions (SEDs), and disk masses (Mdisk) for a sample of 38 HAeBe stars, comparing them to analogous correlations found for classical T Tauri stars. Our goal is to shed light on the timescale and physical processes that drive evolution of intermediate-mass pre-main sequence objects. Macc shows a dissipation timescale \tau = 1.3^{+1.0}_{-0.5} Myr from an exponential law fit, while a power law yields Macc(t) \propto t^{-\eta}, with \eta = 1.8^{+1.4}_{-0.7}. This result is based on our whole HAeBe sample (1-6 Msun), but the accretion rate decline most probably depends on smaller stellar mass bins. The near-IR excess is higher and starts at shorter wavelengths (J and H bands) for the strongest accretors. Active and passive disks are roughly divided by 2 x 10^{-7} Msun/yr. The mid-IR excess and the SED shape from the Meeus et al. classification are not correlated with Macc. We find Macc \propto Mdisk^{1.1 +- 0.3}. Most stars in our sample with signs of inner dust dissipation typically show accretion rates ten times lower and disk masses three times smaller than the remaining objects. The trends relating Macc with the near-IR excess and Mdisk extend those for T Tauri stars, and are consistent with viscous disk models. The differences in the inner gas dissipation timescale, and the relative position of the stars with signs of inner dust clearing in the Macc-Mdisk plane, could be suggesting a slightly faster evolution, and that a different process - such as photoevaporation - plays a more relevant role in dissipating disks in the HAeBe regime compared to T Tauri stars. Our conclusions must consider the mismatch between the disk mass estimates from mm fluxes and the disk mass estimates from accretion, which we also find in HAeBe stars.Comment: 11 pages, 7 figures, 1 appendix. Accepted in A&
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