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An overview of the recent operations and the main results of cesium injection in the Source for the Production of Ions of Deuterium Extracted from Rf plasma (SPIDER) negative ion source are described in this contribution. In experiments without cesium injection, all SPIDER plants were tested to verify the basic expectations on the operational parameters (e.g., electron cooling effectiveness of magnetic filter field) and to determine its operational region. For beam properties, it was shown that the current density varies across the beam in the vertical direction. In preliminary cesium experiments, the expected increase of negative ion current and simultaneous decrease of co-extracted electrons were found, along with the influence of the control parameters (polarization of the plasma electrodes, magnetic filter field) on the SPIDER beam uniformity in the horizontal and vertical directions. It was shown that non-Gaussian tails can be identified in the angular distribution on the plane perpendicular to the beam propagation direction. Stray particles, nonhomogeneous beam and large divergence might result in unexpected heat and particle loads over ITER neutral beam injector (NBI) accelerator grids; it is the goal of SPIDER to assess and possibly to identify suitable methods for controlling these beam features. A major shutdown, planned for late 2021, to solve the issues identified during the operation and to carry out scheduled modifications, is outlined. Such improvements are expected to allow SPIDER to pursue the ITER requirements in terms of negative ion current, electron-to-ion ratio, and beam duration.

[ES] Los tejidos de poliéster (PES) son fáciles de cuidar y se secan rápidamente, pero no transpiran, aunque se promueva la sudoración mucho más que el algodón. Conociendo las propiedades higroscópicas del glicerol, el objetivo de este trabajo ha sido aumentar la retención de humedad por parte de tejidos de PES sometidos a tratamientos con glicerol (GL). Además, se ha aplicado la irradiación de microondas y el tratamiento alcalino para aumentar la fijación del GL a los tejidos de PES. Las muestras de PES tratadas se caracterizaron realizando análisis de contenido de humedad, generación de iones negativos, difusión de agua y resistencia al vapor de agua. Disminuyendo la proporción del baño y aumentando el tiempo y la temperatura, la retención de humedad puede llegar casi al 14%, siendo el tratamiento con álcali el que dio un mayor incremento de humedad. El tratamiento con irradiación de microondas a 500W dio lugar a la mayor retención de humedad tras el aclarado. También se compararon las principales propiedades de las fibras tratadas con GL con las de las fibras naturales de algodón y lana. La humedad de las fibras de PES tratadas con GL aumentó significativamente y fue superior a la del algodón e incluso a la de la lana, aunque disminuyó tras varios aclarados. Los resultados obtenidos implican claramente que el tratamiento del tejido de PES con GL da lugar a una clara mejora de la capacidad de retención de la humedad y, en consecuencia, fomenta el confort del tejido, como demostraron los análisis de iones negativos y de resistencia al vapor de agua., [EN] Polyester (PES) fabrics are easy to care for and dry quickly, but do not perspire, even promote sweating much more than cotton. Knowing the glycerol hygroscopic properties our main aim is to promote hydrophilicity to polyester submitted to glycerol (GL) treatments. Furthermore, microwave irradiation and alkaline treatment have been applied to increase GL fixation to PES fabrics. Treated PES samples were characterized by performing moisture content, negative ion, water diffusion and water vapour resistance analyses. By decreasing the bath ratio and increasing the time and temperature the moisture gain can reach almost to 14%, being the treatment with alkali the one which led to the highest moisture increase. Treatment with 500W microwave irradiation led to the highest moisture retention after rinsing. The main properties of the GL-treated fibers were also compared with those of the natural fibers cotton and wool. The moisture in the PES fibers treated with GL significantly increased and was higher than that of cotton and even wool, although this humidity decreased after several rinses. The results obtained clearly imply that treating PES fabric with GL resulted in a clear improvement in the moisture retention capacity and consequently promoted the comfort properties, as demonstrated by the Ret and negative ion analyses., Los autores desean agradecer al Ministerio de Ciencia, Innovación y Universidades de España (Proyecto CTQ2018-094014-B-100) por el apoyo financiero