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Abstract Silicon carbide-based filter elements were catalytically activated to provide filter elements for catalytic tar removal from biomass-derived syngas. The filter element support was coated with CeO 2 , CaO–Al 2 O 3 and MgO with a specific surface of 7.4, 15.9 and 21.9 m 2 /g synthesized by exo-templating with activated carbon. Doping of a MgO coated filter element with 60 wt% NiO has led to an increase of the specific surface from 0.15 to 0.21 m 2 /g, whereas in case of a MgO–Al 2 O 3 coated filter element a decrease from 1.18 to 0.91 m 2 /g was found. An increase of the NiO loading from 6 to 60 wt% on a MgO coated filter element resulted in an increase of the naphthalene conversion from 91 to 100% at 800 °C and a face velocity of 2.5 cm/s at a naphthalene concentration of 5 g/Nm 3 in model biomass gasification gas. In case of a MgO–Al 2 O 3 coated filter element with 60 wt% NiO in addition to complete naphthalene conversion in the absence of H 2 S, a higher conversion of 66% was found in the presence of 100 ppmv H 2 S compared to 49% of the MgO–NiO coated filter element. After scaling up of the catalytic activation procedure to a 1520 mm long filter candle, which shows an acceptable differential pressure of 54.9 mbar, 58 and 97% naphthalene conversion was achieved in the presence and absence of H 2 S, respectively. The calculated WHSV value of 209.6 Nm 3 h −1 kg −1 indicates the technical feasibility of a further increase of the catalytic performance by an increase of the NiO loading.

Samples of two hundred finger‐ and toenails cultured after a 70% alcohol disinfection for 2 min were compared with non‐disinfected samples cultured on a classical way. Alcohol treatment caused a significant decrease in isolation of yeast and moulds. Both organisms were cultivated at 25.5 and 31%, respectively, when not treated with alcohol, whereas the isolation rate dropped to 10 and 17.5%, respectively, after alcohol treatment. Isolation of dermatophytes decreased from 27.5 to 23.5% when alcohol disinfection was used. In conclusion, although alcohol disinfection of nail samples in the laboratory effectively decreases the isolation rate of unwanted contaminants on Sabouraud glucose agar without cycloheximide, it hampers the isolation of dermatophytes and pathogenic yeasts on cycloheximide‐containing media.

There is a growing need to assist those who have suffered an amputation due to vascular diseases, especially in those who have general lower limb weakness and need additional assistance to retain independence and overall quality of life. The CYBERLEGs system is a new artificial physical and cognitive lower-limb replacement system for dysvascular transfemoral amputees intended for assistance in activities of daily living. By lowering the cognitive and metabolic effort of using a prosthetic system, CYBERLEGs is intended to increase the number of amputees using prosthetic systems as well as expand the capabilities of those who use currently available technology.

This paper introduces an adaptive current control strategy for DC-DC boost converters without input-output voltage sensing. In addition, accurate current control is achieved in the presence of dynamical uncertainties. Unlike many controllers available for DC-DC converters, the adaptive controller's stability is guaranteed by Lyapunov stability theory. A comparison to PI counterpart has been carried out. Results show higher performance, which lead to more efficient operations of DC-DC converters.

Abstract In this study, the external surface of a finned tube was coated by 13X zeolite powder, and the CO2 adsorption equilibrium and dynamics were investigated experimentally. A slurry consisting of dionized water, 13X zeolite powder, and Acrylic latex emulsion (ALE) was used to coat the finned tube. The finned tube was coated by deep coating method. The equilibrium isotherms were measured at the range of 20–90 °C and fitted well by the dual-site Langmuir model. The average difference between the model and the results obtained from the experiments is about 2.5%. The nitrogen adsorption/desorption at 77 K was used for characterization of adsorbents. A 11% reduction was observed in pore volume and surface area. The dynamic test showed that the desorption of adsorbed CO2 takes place in about 14 s which is an order of magnitude faster than the fastest developed method. A conservative criterion was developed for estimating adsorbent working capacity. This criterion showed that the working capacities of the adsorbent are about 80% of its ideal values.

Abstract The present paper proposes a way to introduce chemical reactions in composite curves, in such a way that the irreversibility’s generated by the chemical reaction are expressed as equivalent thermal diffusion. The heat of reaction is considered to be released at a “reversible reaction temperature” and the diffusion between this reversible temperature and the actual temperature generates the actual exergy destruction. Corresponding hot and cold curve contributions result in the composite curves, which visualizes the exergy destruction and the chemical pinches which are present in the exchanger and reactor network. The concept is illustrated through an application on chemical recuperation in a gas turbine cycle.

Overzicht van nucleaire activiteiten en hun milieuimpact in Vlaanderen

Abstract Resulting from a Ph.D. research a Vehicle Simulation Programme (VSP) is proposed and continuously developed. It allows simulating the behaviour of electric, hybrid, fuel cell and internal combustion vehicles while driving any reference cycle [Simulation software for comparison and design of electric, hybrid electric and internal combustion vehicles with respect to energy, emissions and performances, Ph.D. Thesis, Department Electrical Engineering, Vrije Universiteit Brussel, Belgium, April 2000]. The goal of the simulation programme is to study power flows in vehicle drive trains and the corresponding component losses, as well as to compare different drive train topologies. This comparison can be realised for energy consumption and emissions as well as for performances (acceleration, range, maximum slope, etc.). The software package and its validation are described in [J. Automot. Eng., SAE IEE 215 (9) (2001) 1043L]. Different hybrid and electric drive trains are implemented in the software [Views on hybrid drive train power management strategies, in: Proceedings of the EVS-17, Montreal, Canada, October 2000]. The models used for the energy sources like fuel cells, batteries, ultracapacitors, flywheels and engine-generator units will be discussed in this paper in three stages: first their functionality and characteristics are described, next the way these characteristics can be implemented in a simulation model will be explained and finally some calculation results will illustrate the approach. This paper is aimed to give an overview of simulation models of energy sources for battery, hybrid and fuel cell electric vehicles. Innovative is the extreme modularity and exchangeability of different components functioning as energy sources. The unique iteration algorithm of the simulation programme allows to accurately simulate drive train maximum performances as well as all kind of power management strategies in different types of hybrid drive trains [IEEE Trans. Veh. Technol., submitted for publication].

Life Cycle Assessment is a tool to assess the environmental impacts and resources used throughout a product's life cycle, i.e., from raw material acquisition, via production and use phases, to waste management. The methodological development in LCA has been strong, and LCA is broadly applied in practice. The aim of this paper is to provide a review of recent developments of LCA methods. The focus is on some areas where there has been an intense methodological development during the last years. We also highlight some of the emerging issues. In relation to the Goal and Scope definition we especially discuss the distinction between attributional and consequential LCA. For the Inventory Analysis, this distinction is relevant when discussing system boundaries, data collection, and allocation. Also highlighted are developments concerning databases and Input-Output and hybrid LCA. In the sections on Life Cycle Impact Assessment we discuss the characteristics of the modelling as well as some recent developments for specific impact categories and weighting. In relation to the Interpretation the focus is on uncertainty analysis. Finally, we discuss recent developments in relation to some of the strengths and weaknesses of LCA.