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In this paper, a numerical study of flow, reactions and NOx emissions from a biomass boiler is presented. Detailed reaction mechanisms for the decomposition of tar species, combustion of hydrocarbons and formation of NOx are employed by adopting appropriate reaction sets from literature. The proposed mechanism is used to perform CFD simulations of a laboratory-scale biomass boiler, and temperature

This paper experimentally investigates the effect of various magnetic fields on the performance of a plate heat exchanger filled with ferrofluids. Spherical nanoparticles Fe3O4 with an average diameter of 20 nm are dispersed into DI-water to synthesize the ferrofluid. Thermal performance and flow characteristics of the ferrofluid with 0.1% particle concentration are investigated based on various a

Context: Continuous experimentation and A/B testing is an established industry practice that has been researched for more than 10 years. Our aim is to synthesize the conducted research. Objective: We wanted to find the core constituents of a framework for continuous experimentation and the solutions that are applied within the field. Finally, we were interested in the challenges and benefits repor

Climate change is identified as a major threat to wetlands. Altered hydrology and rising temperature can change the biogeochemistry and function of a wetland to the degree that some important services might be turned into disservices. This means that they will, for example, no longer provide a water purification service and adversely they may start to decompose and release nutrients to the surface

CO2-expanded liquids (CXLs) is a class of solvent systems giving relatively low viscosity in comparison to neat organic solvents. The challenge is to achieve a high overall polarity of the CXL, despite the presence of compressed liquid CO2. In this study, the relative static permittivity (εr) was measured for binary and ternary one-phase mixtures of CO2 + green solvent using an in-line microfluidi

We present results from neutron-imaging studies of slow, vacuum pyrolysis of beech, poplar and conifer wood, and pelletized biomass from room temperature up to 1000 °C. A detailed and quantitative method to extract 2D (in situ neutron radiography, NR) and 3D (ex situ neutron computed tomography, NCT) information on structural transformation and elemental hydrogen content has been developed. NCT an

Recent findings suggest that the effect of aging on recognition memory is modality-dependent, affecting memory for objects and scenes differently. However, the lifespan trajectory of memory decline in these domains remains unclear. A major challenge for assessing domain-specific trajectories is the need to utilize different types of stimuli for each domain (objects and scenes). We tested the large

Surrogate measures of safety (SMoS) can enable quick, pro-active, and detailed safety evaluations by studying near-crashes. A critical concern regarding SMoS is their validity. This study focused on the validity of two commonly used SMoS indicators—minimum time to collision and post-encroachment time—with a specific focus on bicyclist–motor vehicle interactions. The study was divided into two main

Risk and Vulnerability Assessments (RVAs) are often conducted by public sector organizations to prevent or prepare for hazards and threats. In Sweden, practitioners increasingly adopt approaches that are based on Business Continuity Management (BCM), where Business Impact Assessments (BIA) are used to gain organizational understanding, in favor of more traditional risk assessments. Both processes

Objectives: To compare the atrial fibrillatory rate (AFR) derived from a local right atrial intracardiac recording (RA-FR) and from a single-lead surface electrocardiogram (ECG) during atrial fibrillation (AF) and to evaluate the correlation with transvenous electrical cardioversion (TVEC) threshold (in Joules), number of shocks and cardioversion success rate in horses. Animals: ECGs and clinical

The Dachstein platform was an extensive carbonate platform developed on the westernmost shelf of the Neotethys during the Late Triassic, now preserved in various tectonic units disrupted during the Alpine orogeny. Despite being the focus of a multitude of sedimentological, paleontological and other studies, the demise of this platform remains controversial, with contrasting views on the timing and

En åldrande befolkningen har identifierats som en samhällsutmaning. En tydlig utveckling inom forskning om sådana utmaningar är krav på medverkan från patientgrupper, brukarorganisationer och andra aktörer utanför akademin. Syftet med artikeln är att introducera en modell för utformning och värdering av samverkan mellan akademiska forskare och aktörer utanför akademin. Modellen bygger på en genomg

This paper concerns the role of teachers as street level buerarucrats in Swedish vocational healthcare education for adult students. At the center of the analysis are the challenges related to policy implementation when many of the students are second language speakers and language and communication play a role. Policy documents provide the analysis with a normative framework. Interviews with teac

A simple and novel method is presented to approximate by the lognormal distribution the probability density function of the sum of correlated lognormal random variables. The method is also shown to work well for approximating the distribution of the sum of lognormal-Rice or Suzuki random variables by the lognormal distribution. The method is based on matching a low-order Gauss-Hermite approximatio