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Temperature dependence of the laminar burning velocity for n-heptane and iso-octane/air flames

The heat flux method is advantageous for obtaining adiabatic stretch-less flame and measuring laminar burning velocity, SL, with low uncertainty. However, its implementation is sometimes hampered by the instability, manifested as cellularity of the flame stabilized over a flat perforated burner. This paper summarizes the approaches of flame cellularity abatement on the heat flux burner, which are

Pathway analysis of skeletal kinetic mechanisms for small alcohol fuels at engine conditions

Seven skeletal reaction mechanisms are presented to highlight key chemistry for mechanism reduction of small alcohol fuels at engine conditions. The mechanisms predict ignition delay times, laminar burning velocity, and extinction strain rate, within 5% of their corresponding complex mechanisms used as a start point for reduction. The mechanisms were developed for equivalence ratio range of 0.7–1.

Exposure to wood smoke particles leads to inflammation, disrupted proliferation and damage to cellular structures in a human first trimester trophoblast cell line

The ongoing transition to renewable fuel sources has led to increased use of wood and other biomass fuels. The physiochemical characteristics of biomass combustion derived aerosols depends on appliances, fuel and operation procedures, and particles generated during incomplete combustion are linked to toxicity. Frequent indoor wood burning is related to severe health problems such as negative effec

Enhanced distribution kinetics in liquid-liquid extraction by CO2-expanded solvents

Liquid-liquid extraction (LLE) is a useful extraction technique for highly complex samples, however, it suffers from being slow due to mass transfer limitations. Carbon dioxide expanded liquids (CXL) is a good replacement of traditional organic solvents for extraction, and for the first time, the use of CXL in LLE was evaluated. An equipment consisting of a high-pressure view cell with on-line gas

Sharing economy business models for sustainability

Background: The predominant focus of academic research on the sharing economy has been on Airbnb and Uber; to this extent, the diversity of business models ascribed to the sharing economy has not yet been sufficiently explored. Greater conceptual and empirical research is needed to increase understanding of business models in the sharing economy, particularly attributes that deliver on its purport

The future of evacuation drills : Assessing and enhancing evacuee performance

Evacuation drills are generally the main mechanism for improving or measuring occupant performance in emergency situations, but their effectiveness is often hard to measure, and there is limited evidence for sustained training benefits. However, innovations in technology (e.g., augmented/virtual reality, novel sensors and wearable tech) offer (when combined with new approaches to designing and del

Biomarker profiling beyond amyloid and tau : cerebrospinal fluid markers, hippocampal atrophy, and memory change in cognitively unimpaired older adults

Brain changes occurring in aging can be indexed by biomarkers. We used cluster analysis to identify subgroups of cognitively unimpaired individuals (n = 99, 64–93 years) with different profiles of the cerebrospinal fluid biomarkers beta amyloid 1–42 (Aβ42), phosphorylated tau (P-tau), total tau, chitinase-3-like protein 1 (YKL-40), fatty acid binding protein 3 (FABP3), and neurofilament light (NFL

Does ‘flight shame’ affect social norms? Changing perspectives on the desirability of air travel in Germany

‘Flight shame’ describes an unease about the climate implications of air travel, and bears evidence of a change in social norms that have so far associated flying with social status. This paper discusses whether Fridays for Future demonstrations and ensuing flight shame have influenced social norms regarding the desirability of air travel, and whether this is measurable in a decline in air travel,

Ozone dose dependent formation and removal of ozonation products of pharmaceuticals in pilot and full-scale municipal wastewater treatment plants

The removal of micropollutants from municipal wastewater is challenged by the number of compounds with diverse physico-chemical properties. Ozonation is increasingly used to remove micropollutants from wastewater. However, ozonation does not necessarily result in complete mineralization of the organic micropollutants but rather transforms them into new compounds which could be persistent or have a

From lab-scale to on-site pilot trials for the recovery of hemicellulose by ultrafiltration: Experimental and theoretical evaluations

Spent sulfite liquor (SSL) is a byproduct of the sulfite pulping process of wood. SSL usually contains monosugars and lignosulfonates, which are fermented to produce ethanol and dried to generate lignosulfonate salts. However, the SSL that was used in this work was derived from the first step of a 2-step sulfite pulping process of softwood under mild pulping conditions in the first stage of cookin

Local attitudes towards management measures for the co-existence of seals and coastal fishery - A Swedish case study

Marine mammals and coastal fisheries are two features commonly associated with thriving marine environments, but it is also a case of wildlife impact on human interests. This paper analyses the seal-fisheries encounter in a Swedish Baltic Sea fishery. The problem concerns seals eating fish from the fishing gear which causes considerable economic losses to small-scale fishermen. This mixed-method s

Revisiting diacetyl and acetic acid flames : The role of the ketene + OH reaction

The mechanism of the reaction of ketene with hydroxyl radical has been studied by ab initio CCSD(T)-F12/cc-pVQZ-F12//B3LYP/6-311G(d,p) calculations of the potential energy surface. Temperature- and pressure-dependent reaction rate constants have been computed using the RRKM-Master Equation and transition state theory methods in the temperature range of 300–3000 K and in the pressure range of 0.01–

The feasibility, validity and reliability of a child friendly vestibular assessment in infants and children candidates to cochlear implant

Objectives: The pediatric vestibular assessment has developed significantly in the past two decades, especially in terms of assessment of cochlear implant (CI) candidates. Different methods and test protocols have been applied, however without a general consensus. We present here the feasibility, validity and reliability of a child friendly vestibular testing in use at our department for the asses

Om att undervisa i att hitta och utveckla den egna rösten

På senare år har jag funderat över det faktum att jag och många av mina kollegor undervisar i att hitta och utveckla den egna rösten. Samtidigt som jag känner mig trygg i min roll som lärare och upplever att jag har lätt för att vara konstruktiv i en undervisningssituation har jag också slagits av det motsägelsefulla i att undervisa någon annan i någonting som är så personligt.Hur kan jag hjälpa n

Improved fibre dispersion estimation using b-tensor encoding

Measuring fibre dispersion in white matter with diffusion magnetic resonance imaging (MRI) is limited by an inherent degeneracy between fibre dispersion and microscopic diffusion anisotropy (i.e., the diffusion anisotropy expected for a single fibre orientation). This means that estimates of fibre dispersion rely on strong assumptions, such as constant microscopic anisotropy throughout the white m

Improved modeling of heat transfer in dropwise condensation

Dropwise condensation has drawn significant attention due to its efficient heat transfer performance compared to filmwise condensation. In this paper, typical experimental data for dropwise condensation on smooth hydrophobic surfaces were collected as well as the typical available heat transfer models. The comparisons between the prediction results and the experimental data indicated that the exis

Basic study on estimation method of wall shear stress in common carotid artery using blood flow imaging

In this paper, we propose a method for adaptive selection of the kernel size used in estimation of the wall shear stress (WSS) based on flow velocity profiles obtained by the blood flow imaging method based on enhancement of RF echo signals from blood cells using a singular value decomposition based clutter filter. Two simulation phantom experiments with the Field II program were performed to vali