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A stable and convenient optical system to realize the forward phase-matching geometry for degenerate four-wave mixing (DFWM) is demonstrated in the mid-infrared spectral region by measuring DFWM signals generated in acetylene (C2H2) and hydrogen chloride (HCl) molecules by probing the fundamental ro-vibrational transitions. IR laser pulses tunable from 2900 cm(-1) to 3350 cm(-1) with a 0.025 cm(-1
We study close encounters involving massive main-sequence stars and the evolution of the exotic products of these encounters as common-envelope systems or possible hypernova progenitors. We show that parabolic encounters between low- and high-mass stars and between two high-mass stars with small periastrons result in mergers on time-scales of a few tens of stellar free-fall times (a few tens of ho
Dimethyldodecylamine-N-oxide (DDAO) has only one polar atom that is able to interact with water. Still, this surfactant shows very hydrophilic properties: in mixtures with water, it forms normal liquid crystalline phases and micelles. Moreover, there is data in the literature indicating that the hydration of this surfactant is driven by enthalpy while other studies show that hydration of surfactan
The observation of neutrinoless double-beta decay (0νββ) would show that lepton number is violated, reveal that neu-trinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment covering the inverted ordering region, with effective Majorana neutrino masses of 15 - 50 meV, will require a tonne-scale experiment with excellent energy resolution and extremely
Using both synchrotron-based photoemission electron microscopy/spectroscopy and scanning tunneling microscopy/spectroscopy, we obtain a complete picture of the surface composition, morphology, and electronic structure of InP nanowires. Characterization is done at all relevant length scales from micrometer to nanometer. We investigate nanowire surfaces with native oxide and molecular adsorbates res
In a future fossil-free circular economy, the petroleum-based plastics industry must be converted to non-fossil feedstock. A known alternative is bio-based plastics, but a relatively unexplored option is deriving the key plastic building blocks, hydrogen and carbon, from electricity through electrolytic processes combined with carbon capture and utilization technology. In this paper the future dem
Plants require daily coordinated regulation of energy metabolism for optimal growth and survival and therefore need to integrate cellular responses with both mitochondrial and plastid retrograde signaling. Using a forward genetic screen to characterize regulators of alternative oxidase1a (rao) mutants, we identified RAO2/Arabidopsis NAC domain-containing protein17 (ANAC017) as a direct positive re
The preparation of oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) catalysts with high activity, stability and low platinum loading has always been the focus of research. The single-atom platinum supported catalyst greatly improves the utilization of platinum, but the catalytic activity and selectivity are greatly affected by the platinum coordination environment, and the pre
To harvest the benefits of III-V nanowires in optoelectronic devices, the development of ternary materials with controlled doping is needed. In this work, we performed a systematic study of n-type dopant incorporation in dense InxGa(1-x)P nanowire arrays using tetraethyl tin (TESn) and hydrogen sulfide (H2S) as dopant precursors. The morphology, crystal structure and material composition of the na
The district heating sector is moving into a new era which brings lower temperatures in the heating network which in turn opens up for a more extensive use of low grade heat such as solar heat. This project aims to develop a dynamic simulation model for feeding centrals in order to be able to design and optimize systems for decentralized feeding regardless of heat source. The big challenge lies in
A submerged submarine is highly sensitive to fires since the fire residues cannot be directly ventilated to the atmosphere. Deadly outcome could be the result if the submarine does not reach the surface within time or manages to purify the air while submerged. Reasons for not reaching the surface could be enemies at the surface or system failure. No Swedish submarines are today able to purify fire
This thesis approaches the challenges of data centre resource efficiency and global water scarcity through a techno-economic analysis of a desalination system driven by data centre waste heat. Membrane distillation is selected as a high-potential technology for this application and is examined through a case study of a hypothetical 1.5 MW direct-to-chip data centre located in Barcelona, Spain. Thr
Germanys transition to high shares of variable renewable energy (VRE) is increasingly ex-posing flaws in the country’s current electricity market design, particularly in its contin-ued use of nationally uniform wholesale pricing. This thesis investigates whether nodal pricing, where electricity prices vary locationally to reflect physical system conditions, can improve market efficiency and suppor
The modelling of filtered chemical source terms remains a fundamental challenges for large eddy simulation (LES) of reacting flows, such as combustion. This study investigates various scale similarity models for predicting filtered reaction rates. The theoretical foundation of scale similarity models is reviewed, and several extensions and generalisations are proposed. These include the distinctio
The large-scale applications of anion exchange membrane water electrolysis (AEMWEs) and zinc–air batteries (ZABs) are observably limited by the lack of highly active, multifunctional, and industrially applicable electrocatalysts. In this work, we report a solvent-free rapid pyrolysis strategy that successfully prepares a composite material of Pt8V–V2O3 heterostructure supported on nitrogen-doped p
Renewable diesel fuels may reduce greenhouse gas emissions and particulate matter compared to fossil diesel, but the toxicity of their combustion products remains unclear. This study assessed pulmonary effects of renewable diesel exhaust particles in female C57BL/6NTac mice after single intratracheal instillation (6, 18, or 54 µg/mouse). Particles were generated from renewable fuels (rapeseed meth
With growing interest in sustainable civil supersonic and hypersonic aviation, there is a need to model the combustion of alternative, sustainable jet fuels. This work presents numerical simulations of several related phenomena, including laminar flames, ignition, and spray flames. Two conventional jet fuels, Jet A and JP-5, and two alternative jet fuels, C1 and C5, are targeted. The laminar burni
This work investigates the effects of atmospheric-pressure nanosecond (ns) pulsed plasma discharges on NH3/air flames using optical emission spectroscopy (OES). Firstly, spatially-resolved OES in the 200–800 nm range of NH3/air flames with and without discharges are presented to identify the plasma-induced excited species (such as N2* and H*). Then, time-resolved OES with ns timescale resolution a
Light absorbing carbonaceous aerosols produced from combustion span over a range of physicochemical properties. Soot is the most recognized species in this category and its formation process involves gradual maturation from amorphous young soot with a high hydrogen-to-carbon-ratio toward mature soot aggregates. In this work, the optical response of a single particle soot photometer (SP2) to electr
Three-dimensional Large Eddy Simulations (LES) are conducted on a non-premixed hydrogen-air annular rotating detonation combustor (RDC). A 22-step finite-rate chemistry reaction mechanism and a flow solver previously developed for high-speed reacting flow are used to perform the LES’. The selected case is an RDC designed by the US Air Force Research Laboratory and has been studied experimentally a
