Performance and emissions of an agricultural diesel engine fuelled with different diesel and methyl ester blends

This paper shows the results of an investigation carried out to assess the application of different fuels produced by blending diesel fuel with methyl ester obtained from mixture of 75% (v/v) sunflower oil and 25% (v/v) used cooking oil on a Kubota agricultural indirect injection diesel engine, natural aspirated, and with a rated horsepower of 19.7 kW. Seven fuels, namely diesel fuel; 90:10, 80:20, 70:30, 50:50, 25:75 and 0:100 (%v/v) blends were prepared and tested for the performance of the diesel engine in accordance with the standardised OECD test code 2. The test results showed that the performance of the engine was satisfactory without a significant reduction in power output and torque with blends smaller than 50%. Fuel consumptions with biodiesel were higher than that when fuelled with diesel but differences were not very marked up to 30% blends. As the reduction of the engine thermal efficiency was less than the corresponding reduction in heating value of the different biodiesel blends, the latter resulted in a more complete combustion in comparison with diesel fuel. The oxides of nitrogen (NOx) emissions were found to be reduced as the biodiesel concentration increase, particularly with 70% and 100% blends. The emissions of carbon monoxide (CO) were lower and increased at a lower rate with the oxygen concentration of the exhaust as the biodiesel blends were equal or higher than 50%

Joyce...Bruno..."Ulysses"

Giordano Bruno has been a philosopher traditionally connected to James Joyce. Nevertheless, Bruno’s infl uence has been associated to Joyce’s last and enigmatic work,Finnegans Wake. Apart from this general consideration, this paper tries to prove that Joyce’s youth readings on Giordano Bruno were a serious infl uence on his most famous work Ulysses. Although it might be true that Joyce did not read Bruno as a primary source –he, indeed wrote a review on a book on the Italian thinker, we can conclude that Bruno was an important source on Joyce before he even conceived writing Finnegans Wake. Giordano Bruno ha sido un fi lósofo que se suele relacionar con la obra de James Joyce. Sin embargo, la infl uencia de Bruno se suele asociar con la última y enigmática obra del irlandés, Finnegans Wake. Amén de esta consideración general, este artículo intenta demostrar que las lecturas juveniles de Joyce fueron una infl uencia seria en su obra más conocida, Ulises. Si bien puede ser cierto que no leyó a Bruno en el original, publicó una reseña sobre el pensador italiano y podemos concluir que Bruno fue una fuente importante en Joyce antes de que ni siquiera concibiera la escritura de Finnegans Wake

Nonholonomic constraints in kk-symplectic Classical Field Theories

A $k$-symplectic framework for classical field theories subject to nonholonomic constraints is presented. If the constrained problem is regular one can construct a projection operator such that the solutions of the constrained problem are obtained by projecting the solutions of the free problem. Symmetries for the nonholonomic system are introduced and we show that for every such symmetry, there exist a nonholonomic momentum equation. The proposed formalism permits to introduce in a simple way many tools of nonholonomic mechanics to nonholonomic field theories.Comment: 27 page

Erosion caused by propeller jets in a low energy harbour basin

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Journal of Hydraulic Research on January, 2017, available online at: http://www.tandfonline.com/10.1080/00221686.2016.1252801Field data of a harbour basin are compared with analytical formulations for predicting maximum scouring depth due to propeller jets. Spatial data analysis of seven-year biannual bathymetries quantifies the evolution of the scouring hole along with the sedimentation process within a harbour basin. The maximum scouring depth is found to be of the order of the propeller diameter with a maximum scouring rate within the first six months of docking manoeuvring. Three of the analysed expressions yielded realistic results while observed discrepancies between the theoretical predictions and field data are related to scaling factors. The outcomes of this analysis can be extrapolated to other harbours to improve their management. The obtained results highlight the importance of field data in developing combined physical and numerical models.Peer ReviewedPostprint (author's final draft

LA MEDICIÓN DE LA REPUTACIÓN EMPRESARIAL: PROBLEMÁTICA Y PROPUESTA

La reputación empresarial es un recurso, una capacidad dinámica y un activo intangible, y por tanto, fuente de ventaja competitiva, generadora de resultados superiores. Este hecho justifica el creciente interés de las instituciones de prestigio y del ámbito académico por desarrollar una escala de medida que permita valorar la reputación empresarial como un constructo latente multidimensional. Con el objetivo de mejorar esta situación, este trabajo propone una herramienta de medida que integra las distintas perspectivas de estudio y medidas de la reputación, considerando los distintos grupos de interés y las perspectivas de análisis más utilizadas: actividad de la empresa y producto y/o servicio

TRANSPORT PROCESSES IN THE PLASMA EDGE

Eight samples of different varieties of commercial ice-creams sold in Spain were analysed for their fatty acid composition, with relevance on their trans-fatty acid profile. Saturated fatty acids occurred in the largest proportions in all samples (mean=68,1%), followed by monounsaturated (mean=21,1%) and polyunsaturated fatty acids (mean=5,2%). Trans fatty acids were detected in all samples ranging from 0,5%-19%, mean value 5,7%. Statistical analysis (cluster analysis) based on their fatty acid profile (saturated, monounsaturated and polyunsaturated and trans fatty acids) showed three groups of samples, depending on the main source of fat employed.Ocho muestras de distintas variedades de helados comercializados en España han sido analizadas para determinar su contenido en ácidos grasos de cadena media y larga, con especial interés en el contenido en ácidos grasos trans. La fracción mayoritaria en todos los casos, está constituida por los ácidos grasos saturados, que presentan un valor medio del 68,1%, seguido de la fracción de monoinsaturados (media=21,1%) y poliinsaturados (media=5,1%). El contenido en ácidos grasos trans, detectado en todas las muestras, oscila entre 0,5%-19%, con un valor medio de 5,7%. El análisis estadístico (análisis cluster) realizado, basándonos en el contenido en ácidos grasos saturados, monoinsaturados, poliinsaturados y trans, ha permitido diferenciar tres grupos distintos de helados según la fuente de grasa mayoritaria empleada en su elaboración

Notas sobre la ocurrencia de Pelamis platurus (Reptilia: Serpentes: Hydrophiidae) en el Pacífico Colombiano

The presence of the Pelamis platurus (Linnaeus) in the Colombian Pacific coast, is confirmed based on 35 reports (18 published and 17 unpublished), and 36 individual records in national colections. The pelagic sea snake is commonly found in large yellow and black aggregations along slick and drift lines in the areas of Isla Gorgona-Cabo Marzo. Additionally, the brown pelican Pelecanus occidentalis is recorded for the first time as a predator of Pelamis platurus in the American Pacific.<br>Se discute la presencia de Pelamis platurus (Linnaeus) en el Pacífico colombiano con base en 35 registros (18 publicados y 17 inéditos), y 36 ejemplares en colecciones nacionales. La serpiente marina es común y abundante entre Isla Gorgona y Cabo Marzo, donde forma densas agregaciones amarillas y negras, a lo largo de las costas. Adicionalmente se registra el pelícano marrón Pelecanus occidentalis por primera vez como un depredador de Pelamis platurus en el Pacífico americano

The XMM spectral catalog of SDSS optically selected Seyfert 2 galaxies

We present an X-ray spectroscopic study of optically selected (SDSS) Seyfert 2 (Sy2) galaxies. The goal is to study the obscuration of Sy2 galaxies beyond the local universe, using good quality X-ray spectra in combination with high S/N optical spectra for their robust classification. We analyzed all available XMM-Newton archival observations of narrow emission line galaxies that meet the above criteria in the redshift range 0.05<z<0.35. We initially selected narrow line AGN using the SDSS optical spectra and the BPT classification diagram. We further modeled and removed the stellar continuum, and we analyzed the residual emission line spectrum to exclude any possible intermediate-type Seyferts. Our final catalog comprises 31 Sy2 galaxies with median redshift z~0.1. X-ray spectroscopy is performed using the available X-ray spectra from the 3XMM and the XMMFITCAT catalogs. Implementing various indicators of obscuration, we find seven (~23%) Compton-thick AGN. The X-ray spectroscopic Compton-thick classification agrees with other commonly used diagnostics, such as the X-ray to mid-IR luminosity ratio and the X-ray to [OIII] luminosity ratio. Most importantly, we find four (~13%) unobscured Sy2 galaxies, at odds with the simplest unification model. Their accretion rates are significantly lower than the rest of our Sy2 sample, in agreement with previous studies that predict the absence of the broad line region below a certain Eddington ratio threshold.Comment: 12 pages, 6 figures, accepted for publication in A&