2,347 research outputs found
Educational Activities to Help Transferring Knowledge in Nuclear: The Seminars of Spanish Young Generation in Nuclear (Jóvenes Nucleares)
From its creation, Spanish Young Generation in Nuclear (Jóvenes Nucleares, JJNN), a non-profit organization that depends on the Spanish Nuclear Society (SNE), has as an important scope to help transferring the knowledge between those generations in the way that it can be possible
From Secondary School To University: Attracting Young Students Towards A Career In Nuclear
From its creation, Spanish Young Generation in Nuclear (Jóvenes Nucleares, JJNN), a non-profit organization that depends on the Spanish Nuclear Society (SNE), has as an important scope to help spread knowledge about nuclear energy, not only pointing out its advantages and its role in our society, but also trying to correct some of the ideas that are due to the biased information and to the lack of knowledge. To try to have success in that goal, some high school lectures were taught and it has been organized regularly a Basic Course on Nuclear Science and Technolog
Absolute colors and phase coefficients of asteroids
Context: We use phase curves of small bodies to measure absolute magnitudes
and, together with complementary theoretical and laboratory results, to
understand their surfaces' micro and macroscopic properties. Although we can
observe asteroids up to phase angles of about 30 deg, the range of phase angles
covered by outer solar system objects usually does not go further than 7 to 10
deg for centaurs and 2 deg for trans-Neptunian objects, and a linear relation
between magnitude and phase angle may be assumed.
Aims: We aim at directly comparing data taken for objects in the inner solar
system (inside the orbit of Jupiter) with data of centaurs and trans-Neptunian
objects.
Methods: We use the SLOAN Moving Objects Catalog data to construct phase
curves restricted to phase angles less than or equal to 7.5 deg, compatible
with the angles observed for the trans-Neptunian/Centaur population. We assume
a linear model for the photometric behavior to obtain absolute magnitudes and
phase coefficients in the ugirz, V, and R filters.
Results: We obtained absolute magnitudes in seven filters for
objects. Our comparison with outer solar system objects points to a common
property of the surfaces: intrinsically redder objects become blue with
increasing phase angle, while the opposite happens for intrinsically bluer
objects.Comment: 8 pages, 11 figures, 1 appendix, accepted for publication in A&
Analysis of the Process Parameter Influence in Laser Cladding of 316L Stainless Steel
Laser Cladding is one of the leading processes within Additive Manufacturing technologies, which has concentrated a considerable amount of effort on its development. In regard to the latter, the current study aims to summarize the influence of the most relevant process parameters in the laser cladding processing of single and compound volumes (solid forms) made from AISI 316L stainless steel powders and using a coaxial nozzle for their deposition. Process speed, applied laser power and powder flow are considered to be the main variables affecting the laser cladding in single clads, whereas overlap percentage and overlapping strategy also become relevant when dealing with multiple clads. By setting appropriate values for each process parameter, the main goal of this paper is to develop a processing window in which a good metallurgical bond between the delivered powder and the substrate is obtained, trying simultaneously to maintain processing times at their lowest value possible. Conventional metallography techniques were performed on the cross sections of the laser tracks to measure the effective dimensions of clads, height and width, as well as the resulting dilution value. Besides the influence of the overlap between contiguous clads and layers, physical defects such as porosity and cracks were also evaluated. Optimum process parameters to maximize productivity were defined as 13 mm/s, 2500 W, 30% of overlap and a 25 g/min powder feed rat
Use and effectiveness of fly goalkeepers in european futsal
Using a fly goalkeeper (FG) is one of futsal´s most specific offensive strategy and gives leverage over the opponent to change the game''s final result. This study will analyze the goals obtained from the use of a FG and relate them to the score momentum variable and others in order to offer a better understanding and to establish if there are differences between main European futsal leagues. Sample made from all offensive situations that lead to a goal while using FG scheme (n=673) during 2014-2015 Spanish, Russian and Italian pro futsal leagues. Observational, nomothetic and multidimensional study. Statistical analysis using the SPSS vr 22 for inferential and descriptive statistics. Chi-square relation for cathegorical variables and Spearman''s Rho to establish non parametrical bi-varial correlations for ordinary variables, establishing significant differences p <0.05. FG strategy obtains 15.33% of the total goals. The league''s behaviour very similar, except in the Italian league, which scores more goals with their attack than against its defence, making differences between goals scored as local and visitor both in attack and defence
Amortiguación de la fluorescencia del carbazol por alcaloides tropánicos (I)
The fluorescence quenching of carbazole by tropanic alkaloids in ciclohexane has been studied in the steady-state. The results obtained supports hydrogen-bond formation both in the ground and excited states. The values of the equilibrium constants are Kg 18.0 M-1 Y 158 < Ke < 430 M-1 both for the ground and excited states respectively.La desactivación de la fluorescencia del carbazol por alcaloides tropánicos en ciclohexano ha sido estudiada en estado estacionario. Los resultados obtenidos indican la formación de un complejo por enlace de hidrógeno tanto en el estado fundamental como en el excitado. Los valores de las constantes de equilibrio son Kg = 18.0 M-1 y 158 < Ke < 430 M-1 para el estado fundamental y el excitado respectivamente
Estudio de la obesidad y del sobrepeso como factores de riesgo de la prevalencia y severidad del asma en niños de Valencia
[email protected]; [email protected]; [email protected]:
La obesidad y el sobrepeso se han descrito como factores de riesgo asociados a la prevalencia y severidad del asma en niños y adolescentes. El objetivo del estudio ha sido el valorar el papel de la obesidad en el asma infantil.
Ámbito de estudio y sujetos:Estudio realizado en niños y adolescentes entre 8 y 15 años, elegidos por un muestreo aleatorio tipo cluster entre los niños que estudiaban en 80 colegios, el cual representa el 30% de los colegios de la ciudad de Valencia.
Material y métodos:El análisis de los datos se organizó en dos grupos, obesos (aquellos niños en un percentil superior al 85 del Índice de Masa Corporal (kg/m2), tomando como referencia la población española) y no obesos, cuando no cumplian esta condición. Se calcularon la prevalencia de los diferentes parámetros con un intervalo de confianza al 95%, y el riesgo relativo (RR) de los síntomas compatibles con asma entre niños obesos comparándolos con los no obesos.
Resultados: No se obtuvo un riesgo relativo significativo para la obesidad con respecto al asma en aquellos niños por encima del percentil 85. Por otra parte, un incremento en el riesgo en relación con la severidad del asma se observó con la obesidad, principalmente en el percentil 85 (RR = 1,51 de sufrir entre 4-12 ataques de pitos y RR = 1,86 de sufrir más de 12 ataques en niños obesos frente a los no obesos)
Conclusiónes: En este estudio, no identificamos un riesgo más alto de asma entre niños obesos frente a los no obesos, aunque encontramos que hubiera un riesgo más alto de severidad de síntomas asmáticos. En relación con la severidad del asma, observamos un riesgo más alto de ataques de pitos y sibilancias entre los niños obesos en los percentiles 85 y 95 del Indice de Masa Corporal.Background: Obesity and overweight have been described as factors associated with asthma. Our aim was to evaluate the role obesity plays on asthma in children.
Scope and subjects: A study carried out on children and teenagers between 8 and 15 years of age, chosen for a cluster-type random sampling from children who studied in 80 schools, which represents 30% of the schools in the city of Valencia.
Material and Methods: The analysed data was organized into two groups, obese (from the Body Mass Index (Kg/m2)), showing children with a percentile over 85% of the measuring reference for the Spanish population) and non obese, when they did not fulfil this condition. The prevalence of the different parameters studied was calculated by an Interval of Confidence of 95%. The risk was calculated (Relative Risk) from those symptoms compatible with asthma among obese children compared to non obese children.
Results: No significant relative risk (RR) was seen for obesity with regards to asthma in those percentiles of obesity over 85. Otherwise, an increase in the relative risk (RR) regarding the severity of asthma was seen in relation to obesity, mainly in the 85th percentile (RR = 1.51 of suffering between 4-12 wheezing attacks and RR = 1.86 of suffering more than 12 attacks in obese children as opposed to non obese children).
Conclusions:
In this study, we did not identify a higher risk of asthma among obese children than among non obese children, although we did find there was a higher risk of severity of asthmatic symptoms. As far as the severity of the asthma is concerned, we saw a higher risk of wheezing and whistling attacks among obese children with the 85th and the 95th percentiles according to the Body Mass [email protected]; [email protected]; [email protected]
Contaminación de aguas por pesticidas
Gas cromotagraphy has been used as analytical technic for some of the pesticides most frequently present in drinking water. The extraction and derivation procedures for some of these contaminatings are indicated the action of choride on paration, one of the most widely used pesticide, has also been studied.Se estudia la cromatografía de gases como técnica analítica de algunos de los pesticidas que más frecuentemente se encuentran contaminado aguas de bebida. Se indican los procedimientos de extracción y derivatización para algunos de estos contaminantes. Además se estudia la acción del cloro sobre el paration por ser uno de los pesticidas más ampliamente utilizados
Amortiguación de la fluorescencia del carbazol por alcaloides tropánicos (II)
The fluorescence quenching of carbazole by tropanic alkaloids in acetonitrile has been studied in the steady-state, in order to determine the bimolecular quenching rate constants. These constants are 1.2x109 l and 5.8x108 M-1 s-1 for the carbazoletropine and carbazole-atropine systems respectively. Besides the appearance of a new fluorescen emission at higher wavelenghts can be observed.Se ha estudiado la amortiguación de la fluorescencia en estado estacionario del carbazol por alcaloides tropánicos en acetonitrilo, en base a determinar las constantes de velocidad bimoleculares de la amortiguación. Estas han resultado ser 1.2x109 ly 5.8x108 M-1 s-1 para los sistemas carbazol-tropanol y carbazol-atropina respectivamente. Además se da cuenta de la aparición de una nueva emisión fluorescente a mayores longitudes de onda
Relaciones entre propiedades fisicoquímicas y moleculares de pesticidas
Using gas chromatography as a cuantitative analisis method, the solubility of 12 organochlor pesticides have been calculated in media of various polarities. Also the partition coefficients in homogeneous and organized media (vesicles) has been calculated. The results obtained has been related its the van der Waals volume.Mediante el uso de la cromatografía de gases como técnica analítica cuantitativa, se ha calculado la solubilidad de 12 pesticidas organoclorados en medios de diversa polaridad, así como la constante de reparto en medios homogéneos y en medios organizados (vesículas). Los resultados obtenidos se han podido correlacionar con el volumen de van der Waals
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