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Hydrogen generation by borohydrides: critical issues for portable applications

High volumetric and gravimetric efficiency are key to potential hydrogen energy carriers. Sodium borohydride emerges as such potentiality and a storage capacity well within DOE targets for 2015. Limitations exist due to the fact that hydrolysis is restricted by available water and due to the lack of low cost re-usable catalysts. An extensive amount of work has been done in our laboratories on Ni and Ru based ca...

Water-based polyurethane dispersions: chemistry, technology and applications

Over the past few decades, polyurethane-polyurea aqueous dispersions (PUDs) have developed a solid reputation for high performance applications, particularly in the field of adhesives and coatings. PUDs are mostly environmentally compatible products; they are totally devoid or contain only low amounts of volatile organic compounds (VOC). This is an important feature in view of the present environmental policies...

NEWALK: novos materiais e componentes para calçado do futuro

A indústria do calçado é o núcleo de um importante cluster da economia nacional. A sua evolução refletiu-se no aumento da produtividade e no valor bruto da produção. Como resultado, o preço do calçado exportado em 2011 subiu para os 23,70 euros/par, tendo o valor global das exportações atingido 1548 milhões de euros (APICCAPS, 2012). Atualmente, este setor procura afirmar-se em nichos de mercado com maior exigê...

Effects of lower limb strengthening on balance and function in persons who suff...

Introduction - Cerebrovascular diseases, and among them, cerebral vascular accidents, are one of the main causes of morbidity and disability at European Union countries. Clinical framework resulting from these diseases include important limitations in functional ability of the these patients Postural control dysfunctions are one of the most common and devastating consequences of a stroke interfering with functi...

Thin slices of interaction : predicting users’ task difficulty within 60 sec

We report on an exploratory study where the first 60 seconds of the video recording of a user interaction are used to predict the user’s experienced task difficulty. This approach builds on previous work on “thin slices” of human-human behavior, and applies it to humancomputer interaction. In the scenario of interacting with a photocopy machine, automated video coding showed that the Activity and Emphasis predi...

Chitosan-based leather functional coatings with improved antimicrobial properties

Among the interesting biological activities that have been ascribed to chitosan, the antimicrobial activity is probably the one that generates the higher number of applications. Developing antimicrobial coatings for footwear components to be used in direct contact with the feet is of great interest; both at industrial level (reducing the possibility of material deterioration and quality loss) and from the consu...

The effect of NaOH on the kinetics of Hydrogen production from sodium borohydri...

Previous work by the authors has demonstrated a high rate and high yield hydrolysis of sodium borohydride in the presence of a Ni-Ru catalyst synthesized by wet chemistry. The catalyst has been fully characterized and utilized more than 300 times, exhibiting high stability and durability. In this work, the effect of temperature on the reaction rate was studied and the activation energy of the process estimated ...

Batch solid sodium borohydride hydrolysis for hydrogen generation : the role of...

The present study reports original experimental work on generation of hydrogen, by hydrolysis of solid sodium borohydride with stoichiometric amount of distilled water (H2O/NaBH4: 2, 2.84 and 3 mol/mol), in the presence of a powder unsupported Ni-Ru based catalyst, reused about 320 times. The experiments, performed in two batch reactors with equal internal volume but with different bottom shapes (flat and conic...

Hydrogen production from sodium borohydride on a Ni-Ru catalyst : an electroche...

Previous work by the authors has demonstrated a high rate and high yield hydrolysis of sodium borohydride, in the presence of a Ni-Ru catalyst synthesized by wet chemistry. The catalyst has been fully characterized and utilized more than 300 times exhibiting high stability and durability. In this work, results of an electrochemical study are reported using the powder catalyst supported on a Ni foam in order to ...

Progress in the catalysed hydrolysis of sodium borohydride as a gydrogen source...