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Hydrogen energy power system for a stand-alone weekend-home application

With an increase in renewable energies penetration and a market potential for the introduction of hydrogen into stand-alone energy systems, aspects related with the immaturity of some of the technologies which integrate the hydrogen sub-system, represent important unresolved technical issues, entailing unavailable components or availability at high costs. As a consequence, there is a growing initiative in the d...

Electronic properties of Al-Nb mixed oxide as a function of their composition

NaOH free hydrolysis of sodium borohydride for hydrogen production

Corrosion inhibition of copper rich Al alloys: layered double hydroxides

Two-step processing of hydrogen storage FeTi Alloys: influence on reaction temp...

In the present work, nanostructured FeTi powders were produced by mechanical alloying, avoiding the unfavorable agglomeration problem by using a low energy milling (e.g. 300 rpm) of pure metallic constituents, Fe and Ti, followed by subsequent heat treatment at 800ºC. A major achievement of this research was to show that by modulating the milling intensity and total milling time, the high temperature synthesis ...

New substituted indazole and condensed pyrazole bisphosphonetes

A Multi-objective optimization for the design and periodic scheduling of multip...

Like most real-world problems, the design of multipurpose batch facilities involves multiple objectives. However the existing literature on the subject has been mainly centred on mono-criterion objectives (Barbosa-Povoa, 2007). Therefore, multi-objective optimisation is a modelling approach that requires further study when applied to such facilities. The best way to deal with various goals simultaneously is to ...

Autonomous hydrogen systems: control strategy

This paper describes the control strategy for a Stand-Alone Energy System Supported by Totally Renewable Hydrogen Production. The basic control strategy considers the pressurized hydrogen gas storage as the energy buffer. The basic logic is that the exceeding renewable energy (solar and wind) is used to accumulate hydrogen, while the fuel cell uses this hydrogen to produce electrical energy within insufficient ...

Utilização de efluentes térmicos industriais no aquecimento de estufas: contrib...

Os efluentes térmicos não são um problema de hoje. Cerca de 60% da produção final de energia eléctrica em Portugal, é produzida por centrais termoelétricas as quais são responsáveis pelo lançamento no meio aquático de cerca de 300.000 m³ h⁻¹ de efluentes térmicos de que resulta o aquecimento desse meio. Este tipo de efluente, caracterizado por uma temperatura relativamente baixa, se não tem aplicação na maior p...

The pros and cons of the dedicated upgrade of the hemicellulosic sugar stream i...

The challenge of the future integrated biorefineries is the full economically utilization of all biomass components with the simultaneously production of fuels and chemicals, preferably of added-value. This can only be achieved by the selective fractionation of the lignocellulosic biomass into its polymeric components, thus increasing their individual upgradeability to enhance the process economics. To reach th...