Design and Development of a Low-Cost Optical Current Sensor

In this paper we demonstrate the design of a low-cost optical current sensor. The sensor principle is the Faraday rotation of a light beam through a magneto-optical material, SF2, when a magnetic field is present. The prototype has a high sensitivity and a high linearity for currents ranging from 0 up to 800 A. The error of the optical fibre sensor is smaller than 1% for electric currents over 175 A.

Low‑cost origami fabrication of 3D self‑aligned hybrid microfluidic structures

[EN] 3D microfluidic device fabrication methods are normally quite expensive and tedious. In this paper, we present an easy and cheap alternative wherein thin cyclic olefin polymer (COP) sheets and pressure sensitive adhesive(PSA) were used to fabricate hybrid 3D microfluidic structures, by the Origami technique, which enables the fabrication of microfluidic devices without the need of any alignment tool. The COP and PSA layers were both cut simultaneously using a portable, low-cost plotter allowing for rapid prototyping of a large variety of designs in a single production step. The devices were then manually assembled using the Origami technique by simply combining COP and PSA layers and mild pressure. This fast fabrication method was applied, as proof of concept, to the generation of a micromixer with a 3D-stepped serpentine design made of ten layers in less than 8 min. Moreover, the micromixer was characterized as a function of its pressure failure, achieving pressures of up to 1000 mbar. This fabrication method is readily accessible across a large range of potential end users, such as educational agencies (schools,universities), low-income/developing world research and industry or any laboratory without access to clean room facilities, enabling the fabrication of robust, reproducible microfluidic devices.

Synthesis and characterization of low-cost materials for aqueous Na-ion batteries

136 p.

The Role of the Demand for Environmental Quality in Driving Transitions to Low-Polluting Energy Sources

4 p.

Reutilización de escoria negra de acería como soporte en biofiltros para la eliminación de H2S del biogás.

[EN]Due to the limitations associated with fossil fuels it is necessary to promote energy sources that are renewable as well as eco-friendly, such as biogas generated in anaerobic digesters. The biogas, composed principally of methane and CO2, is the result of the biodegradation of organic matter under anaerobic conditions. Its use as fuel is limited by the presence of minority compounds such as hydrogen sulphide (H2S); therefore, its pre-treatment is necessary. Currently there are various technologies for the removal of H2S from a gas stream, but most of them are based on physic-chemical treatments which have a number of drawbacks as reactive consumption, generation of secondary flows, etc. Biofiltration has been used as an efficient and low cost alternative to conventional purification processes, and excellent results for the degradation of H2S have been obtained. However process can be limited due to the progressive ageing of the support material, along with the loss of nutrients and other specific characteristics necessary for the good development of biomass. The purpose of this project is to develop a mixed support consisting of a mixture of an organic material and an inorganic support for its application in the removal of the H2S from biogas. This support material helps to optimize the characteristics of the bed and extend its lifespan. The development of such material will contribute to the implementation of biofiltration for treating biogas from anaerobic digesters for its use as biofuel. The inorganic material used is electric arc furnace (EAF) black slag, a by-product generated in large quantities in the production of steel in the Basque Country. Although traditionally the slag has been used in civil engineering, its physicochemical characteristics make it suitable for reuse as a filter medium in biofiltration. The main conclusion drawn from the experimental results is that EAF black slag is a suitable co-packing material in organic biofilters treating H2S-polluted gaseous streams. High pollutant removal rates have been achieved during the whole experimental period. The removal capacity recorded in biofilters with less inorganic material was higher than in those with higher slag portion. Nevertheless, all the biofilters have shown a satisfactory response even at high inlet loads (48 g·m-3·h-1), where the RE has not decreased over 82%.

Diseño y fabricación de un electrodo para electroerosión por penetración mediante fabricación aditiva.

[ES]Este trabajo pretende dar solución a la fabricación de los electrodos utilizados en el proceso de la electroerosión, los cuales presentan numerosos requisitos a los que los electrodos actuales no dan respuesta. Por ello, se propone utilizar un material de bajo coste como núcleo y recubrirlo con una fina capa de cobre mediante laser cladding. De esta forma, se reduce el coste del electrodo manteniendo sus propiedades y se posibilita la creación de geometrías complejas.

Aerosorgailu palen aplikazioetarako pvc espumaren degradazio termiko eta propietate mekanikoen karakterizazioa

[EU]Energia berriztagarria iturri naturaletatik sortzen den energia mota da. Energia lortzeko erabiltzen diren baliabide naturalak asko dira, eguzki-energia, haizea, ura… Energia berriztagarrien artean, eolikoa da zabalkunde handien lortu duena; batez ere ingurumen-inpaktu urriagatik eta bere kostuak gero eta txikiagoak izateagatik. Honen ondorioz, energia garbi, lehiakor eta ekonomikoki bideragarria da gaur egun. Hala ere, aerosorgailu hauen ekoizpen prozesuak desabantaila nabaria aurkezten du palen ontze prozesuan. Tenperatura igoeraren ondorioz material konkretu baten degradazioa dela eta. Ikerketa lan honetan, aerosorgailu palen karakterizazioa egingo da eta ontze prozesuan, “polikloruro de binilo” (PVC)-ak jasaten duen degradazioaren azterketa.