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The dilution effect of N-2/CO2 on the laminar burning velocity of H-2-CO-O-2 mixtures was investigated. The dilution fraction of N-2 and CO2 in the unburned mixtures varied from 0% to 70% and 0%-50%, respectively, and H-2 content in H-2-CO fuels altered from 5% to 100%. All the studies were carried out at standard laboratory conditions (1 atm, 298 K) with equivalence ratio changing from 0.6 to 2.0
The laser wake-field accelerator (LWFA) traditionally produces high brightness, quasi-monoenergetic electron beams with Gaussian-like spatial and angular distributions. In the present work we investigate the generation of ultra-relativistic beams with ring-like structures in the blowout regime of the LWFA using a dual stage accelerator. A density down-ramp triggers injection after the first stage
In past years efforts have concentrated on the development of arrays of Silicon Drift Detectors for X-ray spectroscopy. This is in stark contrast to the little effort that has been devoted to the improvement of germanium detectors, in particular for synchrotron applications. Germanium detectors have better energy resolution and are more efficient in detecting high energy photons than silicon detec
Solar energy ~10 000 times today’s total global energy consumption impinges on Earth. Could we only convert a small fraction of all this energy to useful energy forms, our future energy supply is secured. Photovoltaics converts light to electricity and NW technologies have the potential to provide multi-bandgap materials otherwise not feasible and low material-consumption devices. Nanowire array
https://www.nano.lu.se/nanoenergy/nanowire-photovoltaics - 2026-07-15
Energy use is a topic which is becoming more and more of interest throughout the world. Due to future reduction of the total energy use within the European Union, the permitted energy usage for the building sector is to be reduced. This consequently puts high demands on newly produced buildings, where it is important that both great and small aspects are considered. According to a previous study i
A few large fires in Lithium-ion battery systems are known to have been caused by leaking coolant, and experience from fire testing indicate that coolant can be the origin of violent fires triggered before the onset of thermal runaway in the battery. It is here hypothesized that the common coolants water and ethylene glycol can form flammable gases via electrolysis in the electrical environment fo
Responsible for roughly 40 % of global greenhouse gas emissions, energy usefor heating and cooling in the built environment constitutes a significant portionof annual total carbon emissions. The effort to decarbonise the heating andcooling sector necessitates efficient production, distribution and end use ofenergy. In this context, district heating and cooling is considered one of thecost-efficien
An Eulerian Monte-Carlo approach, the so-called Eulerian stochastic fields (ESF) method is implemented and evaluated for simulation of non-premixed hydrogen/air combustion in supersonic flows. The ESF method is integrated into a compressible flow large eddy simulation (LES) solver, and validated on a supersonic combustor with a strut as flame-holder. Comparison with experimental data and with resu
This paper reports on studies of cellular instability of lean hydrogen/air laminar premixed flames with an equivalence ratio of 0.6 at a 5 atm and a 25 atm pressure. Numerical simulations employing a detailed chemical kinetics mechanism and detailed transport properties are carried out to simulate the initial linear growth of instability as well as the nonlinear evolution of flames. At the initial
Vibrational structures of the C1s and N1s photoelectron spectra of gas-phase HCN have been investigated using monochromated third-generation synchrotron radiation. Both spectra exhibit resolved fine structure associated with several vibrationally excited states. In the C1s spectrum a single vibrational progression is observed, while the N1s spectrum is more complex. High-level ab initio calculatio
We present a study of tunable high-order sum and difference frequency mixing in the 7-70 eV range, in xenon, argon and neon. We mix the light from a terawatt, subpicosecond titanium-sapphire laser and that from a tunable optical parametric generator. The radiation generated through mixing processes involves absorption or emission of one or Mo photons from the weak tunable source. The relative stre
Senior Lecturer, Head of Division Contact details Email: joakim [dot] stenhammar [at] chem [dot] lu [dot] se Phone: +46 46 222 81 51Organisation Physical Chemistry Service point: 1 WebpageJoakim Stenhammars profile in Lund University research portalOther affiliations Office director Physical ChemistryResearch interestsJoakim's research focuses on various aspects of computational and theoretical so
https://www.physchem.lu.se/joakim-stenhammar - 2026-07-15
With growing urbanization and increase in energy demand for space heating and cooling in buildings, reliability, security, distribution of energy and its efficient end use is of utmost importance particularly when emissions from energy use and indoor thermal comfort of the end users isof question. Numerous solutions have been put forth in the field of effective distribution of thermal
Both energy security and the demand for energy, particularly from renewable energy sources, as principle drivers, call for the investigation of renewable energy potential in Poland. The city of Zabrze, located in the Upper Silesia province and urban zone of Katowice, dedicates continuous efforts to the improvement of its waste management against the background of European Union Directives requirin
Both energy security and the demand for energy, particularly from renewable energy sources, as principle drivers, call for the investigation of renewable energy potential in Poland. The city of Zabrze, located in the Upper Silesia province and urban zone of Katowice, dedicates continuous efforts to the improvement of its waste management against the background of European Union Directives requirin
We report on studies of the formamidinium lead triiodide (FAPbI3) perovskite film using time-resolved terahertz (THz) spectroscopy (TRTS) and flash photolysis to explore charge carriers generation, migration, and recombination. The TRTS results show that upon femtosecond excitation above the absorption edge, the initial high photoconductivity (∼75 cm(2) V(-1) s(-1)) remains constant at least up to
Plasmonic materials have optical cross sections that exceed by 10-fold their geometric sizes, making them uniquely suitable to convert light into electrical charges. Harvesting plasmon-generated hot carriers is of interest for the broad fields of photovoltaics and photocatalysis; however, their direct utilization is limited by their ultrafast thermalization in metals. To prolong the lifetime of ho
