4 resultados para Batteries
em Universidad de Alicante
Resumo:
The Mediterranean wall, which is a collection of defensive constructions along the coast, was built during the Spanish War (1936-39) to prevent enemy attacks. It´s called this way like the Atlantic Wall, which was built after the Second World War. These group of buildings consist of batteries, bunkers and barracks placed along the coastline, sometimes next to another kind of infrastructure. Its location (typical of a military strategy) and its peculiar morphology are like another ones: the historical watchtowers ones. They were built by the Kingdom of Spain in the same geography four centuries earlier although, in our case, the buildings are updated to the conditions of contemporary wars: camouflage against air raids. A collection of anti-aircraft devices, placed along the coast since the late 1937, were risen following the instructions of the Valencian State to defend both citizens and cities from the aviation´s bombings. The following military settlements, organized from North to South, are part of the most relevant ones of the coast of Alicante: the Denia and Javea ones, the North of Alicante and Southwest of Alicante ones, the Portichol one, the Galvany´s Clot one and, finally, the Cape and Bay of Santa Pola ones. Remains of more than 60 architectural elements, that document the first concrete´s ruins, are still there. This paper tries to document all of them (providing their location, their morphological genealogy and including some drawings of the current state) to contribute to their revaluation and to help to their necessary protection. They are a legacy of architectural heritage which consolidates and increases the memory of our culture.
Resumo:
During the civil war (1936-39) was built a network of defensive settlements on the coast in anticipation of attacks enemies, forming the so-called 'wall Mediterranean', because of its similarity with the Wall Atlantic of the World War II. These enclaves were composed of groups of batteries, bunkers and buildings. This communication comes to inventory and draw the remains of more than 50 architectures that are located in the Valencian South Coast (from Denia to Torrevieja), documenting the first ruins of hormigion armed with our history. It's a set of military settlements anti-aircraft, mostly scattered coastal rural, which are a great heritage and landscape value, and from which planes haven't been preserved. It is to lift current state record of them all, proceeding to its typological classification, in order to contribute to its assessment and protection on the grounds that they constitute a legacy of architectural heritage that increases our cultural memory.history.
Resumo:
Carbon and graphene-based materials often show some amount of pseudocapacitance due to their oxygen-functional groups. However, such pseudocapacitance is generally negligible in organic electrolytes and has not attracted much attention. In this work, we report a large pseudocapacitance of zeolite-templated carbon (ZTC) based on the oxygen-functional groups in 1 M tetraethylammonium tetrafluoroborate dissolved in propylene carbonate (Et4NBF4/PC). Due to its significant amount of active edge sites, a large amount of redox-active oxygen functional groups are introduced into ZTC, and ZTC shows a high specific capacitance (330 F g−1). Experimental results suggest that the pseudocapacitance could be based on the formation of anion and cation radicals of quinones and ethers, respectively. Moreover, ZTC shows pseudocapacitance also in 1 M lithium hexafluorophosphate dissolved with a mixture of ethylene carbonate and diethyl carbonate (LiPF6/EC+DEC) which is used for lithium-ion batteries and lithium-ion capacitors.
Resumo:
Supercapacitors are energy storage devices that offer a high power density and a low energy density in comparison with batteries. Their limited energy density can be overcome by using asymmetric configuration in mass electrodes, where each electrode works within their maximum available potential window, rendering the maximum voltage output of the system. Such asymmetric capacitors are optimized using the capacitance and the potential stability limits of the electrodes, with the reliability of the design largely depending on the accuracy and the approach taken for the electrochemical characterization. Therefore, the performance could be lower than expected and even the system could break down, if a well thought out procedure is not followed. In this work, a procedure for the development of asymmetric supercapacitors based on activated carbons is detailed. Three activated carbon materials with different textural properties and surface chemistry have been systematically characterized in neutral aqueous electrolyte. The asymmetric configuration of the masses of both electrodes in the supercapacitor has allowed to cover a higher potential window, resulting in an increase of the energy density of the three devices studied when compared with the symmetric systems, and an improved cycle life.