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In this study, a three-dimensional, non-isothermal, two-phase flow mathematical model is developed and applied to investigate the effect of the GDL deformation on transport phenomena and performance of proton exchange membrane (PEM) fuel cells with interdigitated flow fields. The thickness and porosity of the GDL is decreased after compression, and the corresponding transport parameters (permeabil

Flow field design of fuel cells has a significant impact on the distribution of the reactants over the active surface area. In this work, the cell performance and transport characteristics of high temperature proton exchange membrane fuel cells with metal foams as flow distributor were numerically investigated by a three-dimensional and non-isothermal model. Compared to the fuel cell with conventi

The electric resistance is very important for the performance of a proton exchange membrane (PEM) fuel cell. However, the performance analysis is more complex as the cell operates under assembly conditions. At such conditions, the mass transfer is deteriorated but the electric conductivity is favored. In this paper, the electric resistance of a cell is evaluated by application of a recently develo

District heating and cooling systems distribute heat and cooling from a central location to residential and commercial buildings. Hot water, steam or cold water is produced at a central plant and distributed through a pipe network. These systems can integrate renewable energy sources like waste heat, geothermal energy, biomass, and renewable electricity. They are seen as a key component in reducin

https://www.energy.lth.se/research/district-heating-and-cooling - 2026-06-19

The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms, in which one electron is replaced by a negatively charged kaon, is a unique tool to provide precise information on this interaction; the energy shift and the broadening of the low-lyin

The Swedish steel industry stands before a potential transition to drastically lower its CO2 emissions using direct hydrogen reduction instead of continuing with coke-based blast furnaces. Previous studies have identified hydrogen direct reduction as a promising option. We build upon earlier efforts by performing a technological innovation system study to systematically examine the barriers to a t

The Paris Agreement necessitates global net-zero emissions by mid-century, including steel industry emissions that currently amount to about 7% of global energy system emissions. In this article we review the literature on steel decarbonization. Steel industry emission mitigation measures include reduced demand through materials efficiency, increased high-quality recycling, and decarbonization of

Generation and characterization of functional nanostructured magnetic materials The goal of the project is to produce and characterize functional magnetic materials with tailored nanoscale composition and morphology through controlled self-assembly of nanoparticles generated using a physical technique. The generated materials will be characterized using electron microscopy, magnetometry, and synch

https://www.nano.lu.se/phd-project-characterization-magnetic-materials - 2026-06-19

Recent suggestion by Burke and Klippenstein (2017) that chemically termolecular reactions H + O2 + R may significantly affect kinetic pathways under common combustion situations requires careful analysis, since, if included in contemporary kinetic mechanisms, these reactions affect global reactivity and calculated burning velocities of laminar premixed flames. In the view of their impact, a detail

Simultaneous hydrogen (H2) evolution and value−added chemicals production are highly attractive but have not drawn enough attention. Here, we demonstrate a hydrogen sulphide (H2S)−induced product−targeting (HIPT) strategy for the coproduction of H2 and valuable chemical feedstocks from Na2S/Na2SO3 via overall H2S splitting using a MnxCd1−xS/CdyMn1−yS catalyst driven by visible light excitation. Wi

Climate change is more evident than ever as reflected in The European union's environmental directives which say that the carbon emission must be reduced by 20% and 20% of the used energy must come from renewable energy sources until 2020. In Germany political decision has been made that the nuclear power will be replaced by renewable energy in long term. The purpose of the Master Thesis is to

A ternary Mg2NiH4 hydride was synthesized using method that relies on a relatively short mechanical milling time (one hour) of a 2:1 MgH2-Ni powder mixture followed by sintering at a sufficiently high hydrogen pressure (>85 bar) and temperature (>400 degrees C). The ternary hydride forms in less than 2.5 h (including the milling time) with a yield of similar to 90% as a mixture of two polymorphic

Med ökande koncentrationer av koldixodid i atmosfären är den globala uppvärmningen, samt klimatförändringarna ett kritiskt samhällsproblem. För att minska mängden utsläpp av koldioxid har koldioxidavskiljning presenterats som ett alternativ. Koldioxidavskiljning sker genom att rena avgaser från koldioxid för att sedan lagra det i jordskorpan, eller använda i kemiska processer. När tekniken appliceIn order to limit global warming, bioenergy carbon capture and storage (BECCS) technologies are getting increased attention. To meet emission scenarios, an estimated 4000 carbon capture plants are expected to be required by 2030, indicating that progress in carbon capture and storage (CCS) deployment is currently lagging behind expectation. Therefore novel technologies for carbon capture and stora

Pneumatiska bromssystem i tunga fordon är oeffektiva ur energiperspektiv, artikeln beskriver mätningar som jämför pneumatiska och elektromekaniska bromssystem för en batterielektrisk buss.

Thermodynamic stability of an alkaline protease from a new alkaliphilic Nesterenkonia sp. AL-20, was investigated and compared with that of Subtilisin Carlsberg. The amount of calcium bound to the AL-20 protease was determined to be only about 0.14 mol/mol of protease. Differential scanning calorimetry scan of the enzyme at increasing temperature showed the denaturation of the enzyme to be a two-s

This paper assesses the opportunities for resource- and energy-efficient biojet fuel production from forest-based biomass utilising existing industrial infrastructure in Sweden. Two categories of production pathways are considered: one including technologies that are certified for the production of biojet fuel, and the other uncertified technologies under development. Aspects included are producti

Rotational coherent anti-Stokes Raman spectroscopy (CARS) in fuel-rich hydrocarbon flames, with a large content of hydrogen in the product gases (similar to 20%), has in previous work shown that evaluated temperatures are raised several tens of Kelvin by taking newly derived N-2-H-2 Raman line widths into account. To validate these results, in this work calibrated temperature measurements at aroun