1,320 research outputs found
Theoretical study of Diesel fuel reforming by a non-thermal arc discharge
International audienceNitrogen oxides are in the center of future EURO VI norm, the European anti-pollution norm namely for Diesel powered vehicles. NOx (NO, NO2,...) are very irritant pollutants for people and are considered as tropospherical ozone precursors. Their effect is observed when ozone peak pollution is noticed during rush hours. A promising post-treatment technology is to add a NOx trap in exhaust line to store NOx under nitrate form. An alternative to fuel-air ratio increase and catalytic tech-nologies purge is the use of non-thermal plasma. Plasma reforming of diesel fuel and exhaust gas mix-ture creates reducing chemical species like hydrogen and carbon monoxide, which are able to purge the NOx trap
Characterization of a low current-high voltage air arc discharge at high pressure
http://icpig2007.ipp.cas.cz/files/download/cd-cko/ICPIG2007/pdf/3P10-97.pdfInternational audienc
Optical Analysis of a Hexagonal 42kWe High-flux Solar Simulator
AbstractA 42-kWe high-flux solar simulator with hexagonal reflector symmetry has been designed, built and optically characterized at IMDEA Energy Institute, Spain. This facility makes possible the lab-scale generation of a quasi-uniform high radiation flux density and high stagnation temperatures and it will be used as a platform for analyzing processes under concentrating solar energy conditions; for instance, central receivers in concentrating solar power plants and solar fuel production process in thermochemical reactors. The high-flux solar simulator consists of seven reflector-lamp pairs arranged in the center and vertices of a regular hexagon. The 6-kWe Xe short arc lamps are allocated in the primary focus of the corresponding truncated ellipsoidal reflector. This hexagonal symmetry provides compactness and quasi-uniform spatial distribution of the radiation at the system common focal plane.This work presents the experimental characterization of the solar simulator optical performance. Preliminary measurements indicate an average flux density at the focal plane of 3.5 MW/m2 that means 3,500 suns (1 sun = 1kW/m2) and stagnation temperature of approximately 2,800K
High Energy Neutrino Telescopes in the Northern Hemisphere
We review the status and results of the high energy neutrino telescopes in
the Northern Hemisphere, namely ANTARES and Baikal (NT200+).Comment: Contribution to VLvNT 2011, to be published in NIM A, 6 pages, 8
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Gestión del Talento Humano^aCalidad de Vida laboral
La calidad de vida laboral tiene como objetivo, buscar un ambiente laboral sano y seguro, ya que es una forma de mejorar la motivación y productividad de sus empleados.
En cuanto a su composición, desarrollamos conceptos, antecedentes, beneficios, importancia de la calidad de vida laboral (CVL), nos enfocamos en la teoría de la motivación e higiene de Herzberg, las condiciones objetivas y subjetivas de la CVL. Abordamos los diferentes modelos de aplicación de la CVL según sus diferentes autores y las normas de higiene y seguridad ocupacional que contribuyen a la CVL.
Las técnicas para el desarrollo de este informe, fue la recopilación de información de distintas fuentes bibliográficas, tomando como base los libros administración de recursos humanos 8va edición México 2007, gestión del talento humano 3era edición, México 2009 del autor Idalberto Chiavenato. De igual manera este informe se hizo aplicando las normas APA sexta edición.
Cabe mencionar que los resultados de esta investigación están basados en la normativa de presentación de seminario de graduación de la UNAN-Managua. Los principales términos descriptores son Introducción, justificación, objetivos del informe, desarrollo teórico, conclusiones y bibliografías
Caracterização do processo de pirólise de resíduos de polistireno expandido
From the different existing methods for plastic recycling, pyrolysis offers the possibility of solving mechanical recycling limitations, which requires large amounts of clean, separate and homogeneous plastic waste in order to be able to guarantee the quality of the final product. In pyrolysis, it is not necessary to classify or clean the different types of plastic waste and it is possible to process waste contaminated with food and chemical products, such as insecticides, herbicides and fertilizers, reducing classification and cleaning costs. Pyrolysis consists of the chemical decomposition of plastic materials by thermal degradation in the absence of oxygen. In this work the results obtained from the pyrolysis ofwaste expanded polystyrene (EPS) in a batch reactor, varying the pyrolysis temperature are presented. It was experimented with a mass of 500 g and temperatures of 350, 400 and 450 ° C. The results indicate that the highest conversion performance in to liquid hydrocarbon was obtained at a temperature of 450 ° C. The lowest yield of liquid hydrocarbon was obtained at the temperature 350 ° C.De los diferentes métodos existentes para el reciclaje de plástico, la pirólisis ofrece la posibilidad de resolver las limitaciones del reciclado mecánico, el cual necesita grandes cantidades de residuos plásticos limpios, separados y homogéneos para poder garantizar la calidad del producto final. En la pirólisis, no es necesaria la clasificación ni limpieza de los distintos tipos de residuos plásticos y es posible procesar residuos contaminados con alimentos y productos químicos, como insecticidas, herbicidas y fertilizantes, reduciendocostos de clasificación y limpieza. La pirólisis consiste en la descomposición química de los materiales plásticos por degradación térmica en ausencia de oxígeno. En este trabajo se presentan los resultados obtenidos de la pirólisis de residuos de poliestireno expandido (EPS) en un reactor tipo batch, variando la temperatura de pirólisis. Se experimentó con una masa de 500 g y temperaturas de 350, 400 y 450 °C. Los resultados indican que el mayor rendimiento de conversión en hidrocarburo líquido fue a una temperatura de 450 °C. El menor rendimiento de hidrocarburo líquido se obtuvo a la temperatura de 350 °C.Dos diferentes métodos existentes para a reciclagem do plástico, a pirólise oferece a possibilidade de resolver as limitações da reciclagem mecânica, na qual requerse grandes quantidades de resíduos plásticos limpos, separados e homogéneos para garantir a qualidade do produto final. Na pirólise, não é necessário classificar ou limpar os diferentes tipos de resíduos plásticos e é possível processar resíduos contaminados com alimentos e produtos químicos, como inseticidas, herbicidas e fertilizantes, reduzindo os custos de classificação e limpeza. A pirólise consiste na decomposição química de materiais plásticos por degradação térmica na ausência de oxigênio. Este trabalho apresenta os resultados obtidos da pirólise de resíduos de poliestireno expandido (EPS) em um reator tipo batelada, alterando a temperatura de pirólise. Os teste forem realizados com uma massa de 500 g e temperaturas de 350, 400 e 450 ° C. Os resultados indicam que a maior eficiência de conversão em hidrocarboneto líquido foi a uma temperatura de 450 ° C. O menor rendimento de hidrocarboneto líquido foi obtido a uma temperatura de 350 ° C
Aplicación de técnicas de organización industrial en procesos de aprendizaje cooperativo: un caso de estudio en innovación docente. Póster
De las técnicas convencionales de aprendizaje cooperativo tales como Torneos de Equipos de Aprendizaje
(Teams Games Tourament, TGT), Rompecabezas (Jigsaw), Grupos de Investigación (Research Group, RG),
División de estudiantes en Equipos (Students Teams Archievement división, STAD), Círculos de Aprendizaje
(Circles of learning, CL) se desprenden las bases que han de servir al proceso de aprendizaje dentro del
marco de estudios Universitarios propuesto por los requisitos de la declaración de Bolonia.
En este caso de estudio, se pretende presentar un modelo que incorpora sobre las técnicas
convencionales anteriormente descritas, técnicas correspondientes a la ingeniería de organización
industrial, tales como KAIZEN o “mejora continua”, SHOJINKA o “rotación de tareas” y GUNG HO “todos a
una o todos juntos”. De esta forma se asimila el alumnado universitario a los recursos disponibles y las
materias de estudio y los proyectos de investigación junior a las necesidades del sector industrial.Campus Mare Nostrum, Universidad Politécnica de Cartagena, Universidad de Murcia, Región de Murci
Sustainable Ethanol Production From Sugarcane Molasses by Saccharomyces cerevisiae Immobilized on Chitosan-Coated Manganese Ferrite
The interaction between nanostructures and yeast cells, as well as the description of the effect of nanoparticles in ethanol production are open questions in the development of this nanobiotechnological process. The objective of the present study was to evaluate the ethanol production by Saccharomyces cerevisiae in the free and immobilized state on chitosan-coated manganese ferrite, using cane molasses as a carbon source. To obtain the chitosan-coated manganese ferrite, the one-step coprecipitation method was used. The nanoparticles were characterized by X-ray diffraction obtaining the typical diffraction pattern. The crystal size was calculated by the Scherrer equation as 15.2 nm. The kinetics of sugar consumption and ethanol production were evaluated by HPLC. With the immobilized system, it was possible to obtain an ethanol concentration of 56.15 g/L, as well as the total sugar consumption at 24 h of fermentation. Productivity and yield in this case were 2.3 ± 0.2 g/(L * h) and 0.28 ± 0.03, respectively. However, at the same time in the fermentation with free yeast, 39.1 g/L were obtained. The total consumption of fermentable sugar was observed only after 42 h, reaching an ethanol titer of 50.7 ± 3.1, productivity and yield of 1.4 ± 0.3 g/(L * h) and 0.25 ± 0.4, respectively. Therefore, a reduction in fermentation time, higher ethanol titer and productivity were demonstrated in the presence of nanoparticles. The application of manganese ferrite nanoparticles shows a beneficial effect on ethanol production. Research focused on the task of defining the mechanism of their action and evaluation of the reuse of biomass immobilized on manganese ferrite in the ethanol production process should be carried out in the future
In vitro Inhibition of Pancreatic Lipase by Polyphenols: A Kinetic, Fluorescence Spectroscopy and Molecular Docking Study
Svrha je ovog istraživanja bila ispitati molekulsko uklapanje i inhibicijski učinak četiri fenolna spoja pronađena u ljutim papričicama, i to: kavene kiseline, p-kumarne kiseline, kvercetina i kapsaicina, na aktivnost lipaze izolirane iz svinjske gušterače. Najjači inhibicijski učinak imao je kvercetin (IC50=(6.1±2.4) μM), zatim p-kumarna (170.2±20.6) μM) i kavena kiselina (401.5±32.1) μM), dok su kapsaicin i ekstrakt ljute papričice imali iznimno slab učinak. Svi polifenolni spojevi imali su inhibicijski učinak miješanog tipa. Mjerenjem fluorescencije utvrđeno je da su polifenolni spojevi ugasili prirođenu fluorescenciju lipaze izolirane iz gušterače, i to pomoću statičkog mehanizma. Sekvencija Stern-Volmerove konstante bila je: kvercetin, kavena kiselina, te p-kumarna kiselina. Rezultati ispitivanja molekulskih uklapanja pokazali su da se kavena kiselina, kvercetin i p-kumarna kiselina vežu blizu, za razliku od kapsaicina koji se veže daleko od aktivnog mjesta. Vodikove veze i hidrofobne pi-interakcije glavni su načini međusobnog povezivanja polifenolnih spojeva u lipazi izoliranoj iz gušterače.The inhibitory activity and binding characteristics of caffeic acid, p-coumaric acid, quercetin and capsaicin, four phenolic compounds found in hot pepper, against porcine pancreatic lipase activity were studied and compared to hot pepper extract. Quercetin was the strongest inhibitor (IC50=(6.1±2.4) μM), followed by p-coumaric acid ((170.2±20.6) μM) and caffeic acid ((401.5±32.1) μM), while capsaicin and a hot pepper extract had very low inhibitory activity. All polyphenolic compounds showed a mixed-type inhibition. Fluorescence spectroscopy studies showed that polyphenolic compounds had the ability to quench the intrinsic fluorescence of pancreatic lipase by a static mechanism. The sequence of Stern-Volmer constant was quercetin, followed by caffeic and p-coumaric acids. Molecular docking studies showed that caffeic acid, quercetin and p-coumaric acid bound near the active site, while capsaicin bound far away from the active site. Hydrogen bonds and π-stacking hydrophobic interactions are the main pancreatic lipase-polyphenolic compound interactions observed
CXCL6 is an important paracrine factor in the pro-angiogenic human cardiac progenitor-like cell secretome
Studies in recent years have established that the principal effects in cardiac cell therapy are associated with paracrine/autocrine factors. We combined several complementary techniques to define human cardiac progenitor cell (CPC) secretome constituted by 914 proteins/genes; 51% of these are associated with the exosomal compartment. To define the set of proteins specifically or highly differentially secreted by CPC, we compared human mesenchymal stem cells and dermal fibroblasts; the study defined a group of growth factors, cytokines and chemokines expressed at high to medium levels by CPC. Among them, IL-1, GROa (CXCL1), CXCL6 (GCP2) and IL-8 are examples whose expression was confirmed by most techniques used. ELISA showed that CXCL6 is significantly overexpressed in CPC conditioned medium (CM) (18- to 26-fold) and western blot confirmed expression of its receptors CXCR1 and CXCR2. Addition of anti-CXCL6 completely abolished migration in CPC-CM compared with anti-CXCR2, which promoted partial inhibition, and anti-CXCR1, which was inefficient. Anti-CXCL6 also significantly inhibited CPC CM angiogenic activity. In vivo evaluation also supported a relevant role for angiogenesis. Altogether, these results suggest a notable angiogenic potential in CPC-CM and identify CXCL6 as an important paracrine factor for CPC that signals mainly through CXCR2.This study was supported by funding from the European Commission (HEALTH-2009_242038) and by grants from the Spanish Ministry of Science and Innovation (SAF2012-34327 and SAF2015-70882-R to AB and BIO2012-37926 and BIO2015-67580-P to JV), the Research Program of the Comunidad Autónoma de Madrid (S2010/BMD-2420) and the Instituto de Salud Carlos III (RETICS-RD12/0019/0018 to AB and RETICS-RD12/0042/0056 to JV).S
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