Firma de libros en El Corte Inglés, 1974

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201

Influencia de la cizalla en el comportamiento reológico, estructural y estabilidad física de Emulsiones formuladas con aerosil 200, Pluronic pe9400 y aceite esencial de Romero

Se prepararon emulsiones que contenían aceite esencial de romero, un conservante de alimentos natural, mediante la técnica de microfluidización. Se obtuvieron emulgeles añadiendo Aerosil 200. Se examinó la influencia de la presión de homogeneización en el tamaño de gota. Las emulsiones preparadas a 5000 psi en el Microfluidizer mostraron un menor diámetro de Sauter y fueron seleccionadas para llevar a cabo los estudios posteriores. Se ha estudiado la influencia de la cizalla en las propiedades reológicas, estabilidad física y en la microestructura de las emulsiones y emulgeles formados. La emulsión seleccionada mostraba re-coalescencia inducida por cizalla mientras que los emulgeles presentaban un alineamiento de la red-3D. Los emulgeles preparados mostraron un comportamiento dependiente del tiempo. A pesar de que las propiedades viscoelásticas decrecían en el emulgel debido a la acción de cizalla, se detectó una significante mejora en la estabilidad física con la técnica de Multiple Light ScatteringUniversidad de Sevilla. Doble Grado en Física e Ingeniería de Materiale

The monoenergetic approximation in stellarator neoclassical calculations

In the standard "monoenergetic" approach to numerical calculation of stellarator neoclassical transport, to expedite computation, ad-hoc changes are made to the kinetic equation so speed enters only as a parameter. Here we examine the validity of this approach by considering the effective particle trajectories in a model magnetic field. We find monoenergetic codes systematically under-predict the true trapped particle fraction, with the error in the trapped ion fraction being of order unity when the electric field is large, suggesting some results of these codes may be unreliable in this regime. This inaccuracy is independent of any errors introduced by approximation of the collision operator.Comment: 8 pages, 2 figures, submitted to Plasma Phys. Controlled Fusio

Calculation of the bootstrap current profile for the TJ-II stellarator

Calculations of the bootstrap current for the TJ-II stellarator are presented. DKES and NEO-MC codes are employed; the latter has allowed, for the first time, the precise computation of the bootstrap transport coefficient in the long mean free path regime of this device. The low error bars allow a precise convolution of the monoenergetic coefficients, which is confirmed by error analysis. The radial profile of the bootstrap current is presented for the first time for the 100_44_64 configuration of TJ-II for three different collisionality regimes. The bootstrap coefficient is then compared to that of other configurations of TJ-II regularly operated. The results show qualitative agreement with toroidal current measurements; precise comparison with real discharges is ongoing

Electron Bernstein waves emission in the TJ-II Stellarator

Taking advantage of the electron Bernstein waves heating (EBWH) system of the TJ-II stellarator, an electron Bernstein emission (EBE) diagnostic was installed. Its purpose is to investigate the B-X-O radiation properties in the zone where optimum theoretical EBW coupling is predicted. An internal movable mirror shared by both systems allows us to collect the EBE radiation along the same line of sight that is used for EBW heating. The theoretical EBE has been calculated for different orientations of the internal mirror using the TRUBA code as ray tracer. A comparison with experimental data obtained in NBI discharges is carried out. The results provide a valuable information regarding the experimental O-X mode conversion window expected in the EBW heating experiments. Furthermore, the characterization of the radiation polarization shows evidence of the underlying B-X-O conversion process.Comment: 21 pages, 14 figure

Study of the neoclassical radial electric field of the TJ-II flexible heliac

Calculations of the monoenergetic radial diffusion coefficients are presented for several configurations of the TJ-II stellarator usually explored in operation. The neoclassical radial fluxes and the ambipolar electric field for the standard configuration are then studied for three different collisionality regimes, obtaining precise results in all cases

Co-production of knowledge and sustainability transformations: a strategic compass for global research networks

An increasing number of voices highlight the need for science itself to transform and to engage in the co-production of knowledge and action, in order to enable the fundamental transformations needed to advance towards sustainable futures. But how can global sustainability-oriented research networks engage in co-production of knowledge and action? The present article introduces a strategic tool called the ‘network compass’ which highlights four generic, interrelated fields of action through which networks can strive to foster co-production. It is based on the networks’ particular functions and how these can be engaged for co-production processes. This tool aims to foster self-reflection and learning within and between networks in the process of (re)developing strategies and activity plans and effectively contributing to sustainability transformations