450 research outputs found
Materials Handling Vehicles : Policy Framework for an Emerging Fuel Cell Market
© 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Canadian Hydrogen and Fuel Cell Association. Open access under CC BY-NC-ND licenseThere are several challenges to wide-spread commercialisation of the technology hydrogen fuel-cell technology; including reliability and cost implications, infrastructure requirements, and safety aspects of the upcoming technology. Targeted policy initiatives are required to address two significant bottlenecks; reliability and cost constraints. Such policy measures and financial mechanisms providing incentives for manufacturers and end-users of the novel technology create an initial impetus for the introduction of the forthcoming technology into the market place. The current approach, policy mechanisms and their impacts are reviewed in the context of demonstration projects, deploying material handling equipment, involving public-private initiatives.Final Published versio
Sustainable Hydrogen Evaluation in Logistics; SHEL
© 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Canadian Hydrogen and Fuel Cell Association. Open access under CC BY-NC-ND licenseMaterials handling vehicles are currently powered by either electric motor based on lead-acid batteries or combustion engines employing diesel or liquefied petroleum gas. Fuel cells offer significant advantage over the competing technology. SHEL is a three-year European project involving 13 partners from six countries. The overall aim of the project is to deploy 10 fuel-cell powered forklift trucks and associated hydrogen refuelling infrastructure across 3 sites in Europe. Real time information will be gathered, and efficient procedures will be developed to reduce the time required for product certification and infrastructural build approval
Experimental evaluation into novel, low cost, modular PEMFC stack
Attribution-NonCommercial-NoDerivs 3.0 Unported (CC BY-NC-ND 3.0)The Polymer Electrolyte Membrane Fuel Cell (PEMFC), despite being regarded as an ideal replacement to the internal combustion engine, is still not an economically attractive pri-mover due to a number of key challenges that have yet to be fully resolved; some of which include degradation to cell components resulting in inadequate lifetimes, specialised and costly manufacturing processes and poor gravimetric/volumetric energy densities. This paper presents a novel stack concept which removes the conventional bi polar plate (BPP), a component that is responsible for up to 80% of total stack weight and 90+% of stack volume in some designs. The removal of said component not only improves the volumetric and gravimetric energy density of the PEMFC stack but drastically reduces the cost of the stack by removing all costly manufacturing processes associated with PEMFC component machining while the functionality of the traditional BPP is still retained by the unique stack design. The stack architecture is first presented and then the characterisation of the PEMFC is shown over a wide range of operating scenarios. The experimental studies suggest that the performance of the new design is comparable to that of traditional stacks but at significantly less cost price.Final Published versio
Numerical simulation of combined mixing and separating flow in channel filled with porous media
Various flow bifurcations are investigated for two dimensional combined mixing and separating geometry. These consist of two reversed channel flows interacting through a gap in the common separating wall filled with porous media of Newtonian fluids and other with unidirectional fluid flows. The Steady solutions are obtained through an unsteady finite element approach that employs a Taylor-Galerkin/pressure-correction scheme. The influence of increasing inertia on flow rates are all studied. Close agreement is attained with numerical data in the porous channels for Newtonian fluids.Peer reviewedSubmitted Versio
Electromagnetic heating processes: analysis and simulations
Electromagnetic heating (EMH) processes are being increasingly used in
the industrial and domestic sectors, yet they receive relatively little
attention in the thermal engineering domain. Time-temperature
characteristics in EMH are qualitatively different from those in
conventional heating techniques due to the additional parameters (viz
dielectric properties of the material, size and shape of the product
and process frequency). From a unified theory perspective, a
multi-purpose model has been developed in order to obtain the heating
characteristics for an arbitrary processing situation. Theoretical
analyses of various EMH processes in materials of various regular
geometries and a range of physical properties have been undertaken.
Despite the wide spread usage of microwave energy in the food
engineering sector. few understand microwaves and their interactions
with foods. Much of the published research is largely focussed from the
view point of an electrical engineer and aimed at the oven designer.
However, trial-and-error methods are usually employed when developing
microwavable food products and when using microwave ovens. The
presented thesis is focussed from the view-point of the thermal
engineer and aimed primarily at food developers and end users.
The multi-purpose model was then modified specifically for simulating
the heating of food materials in a microwave oven. The validity of the
commonly made assumptions was investigated; in particular the variation
of dielectriC properties during the heating processes and their likely
influence on the model's predictions. Experimental data available in
the literature were compiled and analysed to form a set of equations
for predicting the dielectric properties of various food materials.
Also available correlations for thermal properties were evaluated for a
selected set of experimental data of different food materials. Analyses
were undertaken to demonstrate and evaluate the effects of various
parameters on the heating characteristics of different food materials
commonly heated/cooked in microwave ovens. A qualitative comparison of model predictions and experimental measurements is provided to validate
the physical basis of the model. Findings from the model lead to a
better understanding of the interactions between foods and microwaves. [...cont.
Etude des effets des lipoprotéines de faible densité (LDL) modifiées sur des macrophages murins en culture par l'approche protéomique
Blunt A., Gruffudd P., May J., Ogborn M. & Pinder D., Cultural Geography in Practice
L’ouvrage anglo-saxon pourrait-il apporter à la définition de la géographie culturelle un doux vent de fraîcheur ? Pourrait-il enfin articuler les centres d’intérêts de la discipline aux approches plus communes de la production et de l’organisation des territoires ? C’est la question que l’on peut se poser lorsque l’on ouvre aujourd’hui un ouvrage de géographie culturelle, dont on sait la profusion contemporaine et la variété qualitative. D’entrée de jeu, l’ouvrage est présenté par ses auteur..
Role and Important Properties of a Membrane with Its Recent Advancement in a Microbial Fuel Cell
Microbial fuel cells (MFC) are an emerging technology for wastewater treatment that
utilizes the metabolism of microorganisms to generate electricity from the organic matter present in
water directly. The principle of MFC is the same as hydrogen fuel cell and has three main components
(i.e., anode, cathode, and proton exchange membrane). The membrane separates the anode and
cathode chambers and keeps the anaerobic and aerobic conditions in the two chambers, respectively.
This review paper describes the state-of-the-art membrane materials particularly suited for MFC and
discusses the recent development to obtain robust, sustainable, and cost-effective membranes. Nafion
117, Flemion, and Hyflon are the typical commercially available membranes used in MFC. Use of nonfluorinated polymeric membrane materials such as sulfonated silicon dioxide (S-SiO2) in sulfonated
polystyrene ethylene butylene polystyrene (SSEBS), sulfonated polyether ether ketone (SPEEK) and
graphene oxide sulfonated polyether ether ketone (GO/SPEEK) membranes showed promising
output and proved to be an alternative material to Nafion 117. There are many challenges to selecting
a suitable membrane for a scaled-up MFC system so that the technology become technically and
economically viable
La production imaginaire d’une « Capitale de l’Europe » : vers la territorialisation d’une identité collective européenne ?
L’article comporte deux volets. D’une part, la définition d’un concept de « production imaginaire de l’espace » qui combine les enseignements de la théorie du paysage d’A. Berque aux développements des « sciences de l’imaginaire » afin de fournir une base théorique à l’idée de « territorialisation de l’identité collective ». Ainsi, l’article contribue à la formalisation théorique du « processus de symbolisation de l’espace » afin de l’intégrer à une approche globale de la production de l’espace. D’autre part, une application pratique d’un tel cadre analytique dans le cas de l’Union européenne. Il s’agit, par conséquent, de dégager un processus de territorialisation d’une identité collective européenne autour des lieux principaux du système politique. La recherche s’est concentrée sur l’étude du réseau imaginaire constitué dans le champ touristique. Les résultats obtenus amènent à soutenir que se développe un espace imaginaire européen plutôt monocentrique en faveur de Bruxelles, malgré l’existence d’une concurrence entre Bruxelles et Strasbourg.This paper has two objectives. First, to define a concept of the « imaginary production of space » which combines Berque’s theory of landscape to the main developments of the « sciences de l’imaginaire » in order to give a theoretical basis to the idea of the « common identity territorialization ». Thus, this paper contributes to the theoretical shaping of a « space symbolization process » in order to integrate it to a production of space global approach. Secondly, to give an empirical test of such an analytical pattern in European Union’s case. Consequently, it intends to shed light on a European common identity territorialization process around the political system’s main places. The research focused on the analysis of the imaginary network built in the touristic field. The results lead to argue that an almost monocentric European imaginary space, in favour of Brussels, is developing, despite the competition between Brussels and Strasbourg
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