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Design guidelines for fluid-elastic instability of tube bundles subjected to two-phase cross flow

Fluid-elastic instability of tube bundles is the main cause of vibration failure of heat exchangers. To establish more reasonable and reliable design guidelines for fluid-elastic instability of tube bundles subjected to two-phase cross flow, we investigated experimentally the effects of the flow conditions of the two-phase flow and the geometrical characteristics of the tube bundles on damping, vi

Molecular determinants of disease severity in urinary tract infection

In the urinary tract, Escherichia coli infection may result in life-threatening disease, or asymptomatic bacterial carriage, comparable to bacterial commensalism in the gut. Pathogenic strains trigger a disease provoking host response which differs depending on the infected organ. The diversity of the response reflects the virulence repertoire of the infecting strain and by the susceptibility of t

Struggles over Human Smuggling in Court: Challenging National and European Border Regimes

In this paper, we explore the ways in which national and European border regimes have been chal- lenged by cases of “compassionate smuggling” of refugees. We centre the analysis around a Swedish case, in which three film makers accompanied a boy from Syria on his journey through Europe in 2015, while at the same time documenting the journey in a documentary film. After the screening of the film inIn this paper, we explore the ways in which national and European border regimes have been challenged by cases of “compassionate smuggling” of refugees. We centre the analysis around a Swedish case, in which three film makers accompanied a boy from Syria on his journey through Europe in 2015, while at the same time documenting the journey in a documentary film. After the screening of the film in t

Emerging local solidarities? Local responses to migration to non-urban communities in the south of Sweden

In a time of harshening border control and public discourses on securitisation and “crisis” at the national as well as European levels, it is of interest to explore local responses to migration, especially in areas outside of the larger cities. Local organising in support of different migrant groups, as well as more hostile or openly racist responses, are not new phenomena. However, we argue that

Multi-particle momentum correlations extracted using covariance methods on multiple-ionization of diiodomethane molecules by soft-X-ray free-electron laser pulses

Momenta of ions from diiodomethane molecules after multiple ionization by soft-X-ray free-electron-laser pulses are measured. Correlations between the ion momenta are extracted by covariance methods formulated for the use in multiparticle momentum-resolved ion time-of-flight spectroscopy. Femtosecond dynamics of the dissociating multiply charged diiodomethane cations is discussed and interpreted b

Active Posts in Deterministic Lateral Displacement Devices

Using electrically connected metal-coated posts in a deterministic lateral displacement (DLD) device and applying electric fields, electrokinetics is used to tune separations, significantly decrease the critical size for separation, and increase the dynamic range with switching times on the order of seconds. The strength of DLD stems from its binary behavior. To first approximation, particles move

Decision-making process for addressing bottleneck problems in district heating networks

Lower system temperatures in district heating (DH) grids are important factors for system efficiency. Lower system temperatures lead, for example, to lower heat losses and higher production unit efficiency. One obstacle to lower supply temperatures are so-called bottlenecks in DH networks. Bottlenecks are areas in DH networks of very low differential pressure, which makes it difficult to supply th

Kinetic evaluation of lime for medium-temperature desulfurization in oxy-fuel conditions by dry sorbent injection

With increasing emphasis on the control of greenhouse gases, power plants may move towards oxy-fuel technologies rather than air-fired plants. This move leads to a change in the feed to the desulfurization unit, which also needs to be adapted along with the power plant. Most existing plants already have functioning desulfurization units, which need to be retrofitted for the new conditions. In the

The curious case of online information search

In a rapidly digitalizing world, the increasing importance of online information channels is repeatedly stated. But little is known about the procedure of online information search. This study examines the process of booking a journey via digital devices. It is based on a multi-method approach including interview and experiment. Results show that tourists’ online searching behaviour is less ration

Coastal management in Portugal : Practices for reflection and learning

Portugal is located in the southwest of Europe. From economic, cultural, social and environmental point of views, Portuguese coastal areas face multiple challenges related to the coastal management policy, the functionality of the governmental services and the responses to the society, in particular, to the affected citizens. Qualitative and quantitative understanding of the coastal morphological

Anthropogenic nitrogen enrichment enhances soil carbon accumulation by impacting saprotrophs rather than ectomycorrhizal fungal activity

There is evidence that anthropogenic nitrogen (N) deposition enhances carbon (C) sequestration in boreal forest soils. However, it is unclear how free-living saprotrophs (bacteria and fungi, SAP) and ectomycorrhizal (EM) fungi responses to N addition impact soil C dynamics. Our aim was to investigate how SAP and EM communities are impacted by N enrichment and to estimate whether these changes infl

The Variation of Pre-movement Time in Building Evacuation

In order to provide a reliable evacuation design assessment, data showing the variation in pre-movement time is of vital importance. The pre-movement time is in many cases regarded as the main time period during an evacuation assessment. Therefore, forty unannounced evacuation experiments for six different occupancies were analysed to quantify pre-movement time during building evacuation, i.e., th

Controlling distribution inventory systems with shipment consolidation and compound Poisson demand

We consider a one-warehouse-multiple-retailer inventory system where the retailers face stochastic customer demand, modelled as compound Poisson processes. Deliveries from the central warehouse to groups of retailers are consolidated using a time based shipment consolidation policy. This means that replenishment orders have to wait until a vehicle departures, which increases the lead time for the

Green solvents-based fractionation process for kraft lignin with controlled dispersity and molecular weight

The aim of this work is to develop a novel green solvent based sustainable process to refine lignin into low molecular weight (LMW) and high molecular weight (HMW) fractions. Lignin dispersity reduction were experimentally determined using four solvent mixtures, and benchmarked against eight pure solvents. Data outputs were used for modelling the integrated fractionation process. Dispersity reduct