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A large number of measurement techniques have been developed or adapted from other fields to measure various parameters of engine particulates. With the strict limits given by regulations on pollutant emissions, many advanced combustion strategies have been developed towards cleaner combustion. Exhaust gas recirculation (EGR) is widely applied to suppress nitrogen oxide (NOx) and reduce soot emiss

This work aims to study the effect of fuel inhomogeneity on the ignition process and subsequent combustion in a compression ignition Partially Premixed Combustion (PPC) engine using a primary reference fuel (PRF) in low load conditions. Five cases with injection timings ranging from the start of injection (SOI) at -70 crank angle degrees (CAD) to -17 CAD have been studied numerically and experimen

In-cylinder heat losses in diesel engines decrease engine efficiency significantly and account for approximately 14-19% [1, 2, 3] of the injected fuel energy. A great part of the heat losses during diesel combustion presumably arises from the flame impingement onto the piston. Therefore, the present study investigates the heat losses during flame impingement onto the piston bowl wall experimentall

The combustion process in a homogeneous charge compression ignition (HCCI) engine is mainly governed by ignition wave propagation. The in-cylinder pressure, heat release rate, and the emission characteristics are thus largely driven by the chemical kinetics of the fuel. As a result, CFD simulation of such combustion process is very sensitive to the employed reaction mechanism, which model the real

Konferensbidraget presenterar en forskningsplan för studiet av möjligheter och utmaningar behäftade med aggregering (insamling och sammanvägning) av den information som sammanställs i svenska myndigheters risk- och sårbarhetsanalyser.

The natural gas/diesel dual-fuel engine is an interesting technique to reduce greenhouse gas emission. A limitation of this concept is the emission of un-combusted methane. In this study we analyzed the influence of PFI gas-injection timing on cylinder to cylinder gas-distribution, and the resulting methane emissions. This was done on a 6 cylinder HD engine test bench and in a GT-power simulation

BACKGROUND: The wingless-type mammary tumour virus integration site 5A (WNT5A) agonist Foxy5 was shown in vitro to affect intracellular signalling implicated in the regulation of colonic cancer stem cells (CSCs). MATERIALS AND METHODS: In order to study whether Foxy5 can modulate CSCs, either HT-29 or Caco-2 human colonic cancer cells, both lacking endogenous WNT5A expression, were inoculated subc

Calcium-activated chloride channel regulator 1 (CLCA1) belongs to a group of secreted self-cleaving proteins, which activate calcium-dependent chloride channels. CLCA1 has been shown to participate in the pathogenesis of inflammatory airway diseases such as asthma. Recently, additional functions of CLCA1 have been unveiled, including its metalloprotease property and involvement in mucus homeostasi

Neutron crystallography is a powerful method to determine the positions of H atoms in macromolecular structures. However, it is sometimes hard to judge what would constitute a chemically reasonable model, and the geometry of H atoms depends more on the surroundings (for example the formation of hydrogen bonds) than heavy atoms, so that the empirical geometry information for the H atoms used to sup

One of the most important theological questions in the first Origenist controversy was that of the resurrection of the dead. Jerome accused both Origen and contemporary “Origenists” of speaking only of the resurrection of the body, and not of the flesh, and he claimed that an idea of resurrection without the flesh could not guarantee the identity between the body living on earth and the resurrecte

Vascular pathophysiological changes after haemorrhagic stroke, such as phenotypic modulation of the cerebral arteries and cerebral vasospasms, are associated with delayed cerebral ischemia (DCI) and poor outcome. The only currently approved drug treatment shown to reduce the risk of DCI and improve neurologic outcome after aneurysmal subarachnoid haemorrhage (SAH) is nimodipine, a dihydropyridine

Background Arterial blood gases (ABG) are essential for assessment of patients with severe illness, but sampling is difficult in some settings and more painful than for peripheral venous blood gas (VBG). Venous to Arterial Conversion (v-TAC; OBIMedical ApS, Denmark) is a method to calculate ABG values from a VBG and pulse oximetry (SpO 2 ). The aim was to validate v-TAC against ABG for measuring

On EU media policy with regard to the upcoming EU election

På uppdrag av Naturvårdsverket har avdelningen för Arbets- ochmiljömedicin vid Lunds Universitet utfört en kunskapsinventering blandlandets kommuner kring luftkvalitén på förskolebarns utemiljöer ocheffekter/strategier för att eventuellt förbättra detta. Denna inventeringgenomfördes under hösten 2018 och början av 2019 och ska ligga till grundför det Hälsorelaterade Miljöövervaknings projektet ”Lu

We present an efficient fiber source designed for continuous-wave differential absorption light detection and ranging (CW DIAL) of atmospheric CO 2 -concentration. It has a linewidth of 3 MHz, a tuning range of 2 nm over the CO 2 absorption peaks at 1.572 µm, and an output power of 1.3 W limited by available pump power. Results from the initial CW DIAL testing are also presented and discussed.

Denna rapport redovisar resultaten från ett pilotprojekt i ett större EU baserat Citizen Science projektsom initierats av EEA (European Environmental Agency Area) och ska bidra med kunskap om hurett större Citizen Science projekt kan organiseras när det gäller utskick av information ochutdelning/uppsamling av mätutrustning för luftkvalitetmätningar.Studien är finansierad av Naturvårdsverket och sy

Experiments on the excitation of propagating surface plasmons (SPs) by an ultrashort, high intensity laser interaction with grating targets are reviewed. At intensities exceeding 10 19 W cm -2 on target, i.e., in the strongly relativistic regime of electron dynamics, multi-megaelectronvolt electrons are accelerated by the SP field as dense bunches collimated in a near-tangent direction. By the

Background Pulmonary hypoplasia, characterized by incomplete alveolar development, remains a major cause of mortality and morbidity in congenital diaphragmatic hernia. Recently demonstrated to differentiate from a common bipotent progenitor during development, the two cell types that line the alveoli type 1 and type 2 alveolar cells have shown to alter their relative ratio in congenital diaphragm