High resolution system for nanoparticles hyperthermia efficiency evaluation

A system to evaluate nanoparticles efficiency in hyperthermia applications is presented. The method allows a direct measurement of the power dissipated by the nanoparticles through the determination of the first harmonic component of the in quadrature magnetic moment induced by the applied field. The magnetic moment is measured by using an induction method. To avoid errors and reduce the noise signal a double in phase demodulation technique is used. To test the system viability we have measured nanowires, nanoparticles and copper samples of different volumes to prove by comparing experimental and modeled results

Influencia de las condiciones de almacenamiento sobre la relajación de aceros de pretensado = Influence of storage conditions on prestressing steel relaxation losses

La pérdida de tensión por relajación en las armaduras activas afecta de forma importante a las estructuras de hormigón pretensado. Por ello se realizan ensayos de relajación de los alambres y cordones de pretensado tras su fabricación. Después, el material es enrollado y almacenado durante periodos que en ocasiones pueden superar el año de duración. Generalmente se desprecia la influencia que estas operaciones posteriores a la fabricación pueden tener sobre el material. Sin embargo, diversos fabricantes y suministradores han constatado experimentalmente que, en ocasiones, el material almacenado durante un periodo prolongado presenta pérdidas de relajación mayores que inmediatamente tras su fabricación. En este trabajo se realizan ensayos de laboratorio para comprobar la influencia que el radio de enrollamiento y el periodo de almacenamiento tienen sobre las pérdidas de relajación. También se propone un modelo analítico que permite predecir de manera razonablemente aproximada el valor del ensayo de relajación sobre un alambre sometido a un enrollamiento prolongado. Este modelo explica la evolución del perfil de tensiones durante el proceso de enrollamiento- almacenamiento-desenrollamiento, así como la influencia de las tensiones residuales.Stress relaxation losses on active reinforcement have significant impact on prestressed concrete structures. This is why relaxation tests are carried out on prestressing steel wires and strands after being manufactured. Then, these materials are coiled and stored for a long-term period, sometimes in excess of one year. The influence of these operations, carried out after manufacturing, is usually neglected. Nevertheless, some manufacturers and contractors have noticed that, sometimes, when relaxation tests are carried out after a long-term storage, the relaxation losses found are higher than those measured immediately after manufacturing. In this work, lab tests are performed to check the influence of the coiling radius and the period of storage on the relaxation test. In addition to this, an analytical model is presented to predict the results of a relaxation

Evaluation of the Magnetic Field Generated by the Inverter of an Electric Vehicle

In hybrid and electric vehicles, passengers sit very close to an electric system of significant power, which means that they may be subjected to high electromagnetic fields. The hazards of long-term exposure to these fields must be taken into account when designing electric vehicles and their components. Among all the electric devices present in the power train, the electronic converter is the most difficult to analyze, given that it works with different frequencies. In this paper, a methodology to evaluate the magnetic field created by a power electronics converter is proposed. After a brief overview of the recommendations of electromagnetic fields exposure, the magnetic field produced by an inverter is analyzed using finite element techniques. The results obtained are compared to laboratory measurements, taken from a real inverter, in order to validate the model. Finally, results are used to draw some conclusions regarding vehicle design criteria and magnetic shielding efficiency.

Efecto de la edad relativa en la trayectoria deportiva de los jugadores de baloncesto y de fútbol en España

Las consecuencias de la diferencia de edad cronológica existente entre dos sujetos de un mismo grupo de edad Gutiérrez (2013) son conocidas como efecto de la edad relativa (RAE) y ha sido ampliamente estudiado en varios países y deportes, entre ellos el fútbol y el baloncesto. El semestre del año en el que se nace afecta mucho a lo largo de la vida de todo deportista, ya que las diferencias madurativas existentes entre los jugadores de un mismo grupo de edad influyen para llegar al profesionalismo. Esto ocurre tanto en fútbol como en baloncesto. El presente estudio pretende analizar el efecto de la edad relativa en el fútbol y el baloncesto élite español y sus diferencias. Se ha utilizado una muestra de 1224 jugadores de ACB y LFP, selecciones cadete y juvenil de los dos deportes desde el 2004 hasta el 2013 en los años que se clasificaron para jugar el campeonato de Europa. Los resultados muestran la existencia del efecto de la edad relativa en ambos deportes, y un efecto mayor en edades más tempranas. También se puede observar la diferencia en ambos deportes, siendo más en ACB que en la LFP los seleccionados en edades tempranas. En cambio, de las selecciones de la LFP han logrado más que en ACB el éxito profesional, considerándose como llegar a primera, ya sea en España u otros países.

Seven Ulmus minor clones tolerant to Ophiostoma novo-ulmi registered as forest reproductive material in Spain

The Spanish elm programme began in 1986 in response to the devastating impact of Dutch elm disease on natural elm stands and urban trees. Its main objectives were to conserve remaining genetic resources and select and breed tolerant native elm genotypes. After 27 years of work conducting susceptibility trials on thousands of elm genotypes, the first seven tolerant Ulmus minor trees are now being registered by the Spanish Environmental Administration. This paper presents the results of the susceptibility tests on these clones and their distinctive genetic, morphological and phenological features. In all susceptibility trials the commercial ?Sapporo Autumn Gold? clone, which is highly tolerant to O. novo-ulmi, was used as a control. The registered clones were named ?Ademuz?, ?Dehesa de la Villa?, ?Majadahonda?, ?Toledo?, ?Dehesa de Amaniel?, ?Retiro? and ?Fuente Umbría?. The most tolerant clone was ?Dehesa de Amaniel?, as its wilting values were below 5% during the two consecutive inoculation trials performed in Madrid. ?Fuente Umbría?, tested over four consecutive years in Guadalajara and Palencia, was the Spanish clone with the most reliable tolerance level to O. novo-ulmi. The ?Ademuz? and ?Majadahonda? clones had the highest ornamental scores and are promising trees for use in urban environments and tree breeding for ornamental quality. These two genotypes showed a later bud burst phenology than the other U. minor clones, demonstrating suitability to areas with late frost events. The Spanish programme aims to substantially increase the range of tolerant native elms through new selections and crossings to gain a better understanding of the genetic basis of resistance.