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Third-order double-achromat bunch compressors for broadband beams

Many state-of-the-art applications for linear accelerators, such as free-electron lasers (FELs) and plasma-wakefield accelerators (PWFAs), require small normalized emittances, and PWFAs in particular are very sensitive to transverse slice offsets along the beam. Dispersive systems, such as bunch compressors, can cause different chromatic aberrations, one of which yields transverse slice offsets. I

Lobaria pulmonaria in the southwestern Baltic area

Lungwort lichen, Lobaria pulmonaria (L.) Hoffm., was surveyed in the southwesternBaltic Area in 2016–2018. At each of the localities, the habitat ecology and lichen viability were investigated. A substantial decline was noted, particularly in Skåne. The commonest habitats for L. pulmonaria in southernmost Sweden are lime-maple and species-poor, oligotrophic beech forests, and the commonest substra

Auditor rotations and audit quality : A perspective from cumulative number of audit partner and audit firm rotations

PurposeThe purpose of this paper is to investigate the association between audit rotation – at the audit partner and audit firm level – and audit quality. As mentioned in the literature, audit rotation has several benefits, and one of them is it can bring a fresh look to audit tasks and subsequently improve audit quality. Moreover, audit itself can help a client to improve its financial reporting.

Electron-electron versus electron-phonon interactions in lattice models: Screening effects described by a density functional theory approach

We address the interplay of electron-electron (e-e) and electron-phonon (e-ph) interactions in the Hubbard- Holstein model, using a two-component density functional theory. Exchange-correlation potentials constructed via dynamical mean field theory for a D = ∞ Bethe lattice and analytically for an isolated site give a new perspective on e-ph screening of the e-e interactions and its effect on the

Multi-step enzymatic synthesis of 1,9-nonanedioic acid from a renewable fatty acid and its application for the enzymatic production of biopolyesters

1,9-Nonanedioic acid is one of the valuable building blocks for producing polyesters and polyamides. Thereby, whole-cell biosynthesis of 1,9-nonanedioic acid from oleic acid has been investigated. A recombinant Corynebacterium glutamicum, expressing the alcohol/aldehyde dehydrogenases (ChnDE) of Acinetobacter sp. NCIMB 9871, was constructed and used for the production of 1,9-nonanedioic acid from

Jump height as performance indicator for the selection of youth football players to national teams

BACKGROUND: Different jump tests such as the Countermovement Jump (CMJ), Abalakov Jump (AJ) and Standing Long Jump (SLJ) are often used in practice to evaluate muscular power and functional performance in football. These tests are also used in different selection processes and talent identification, but the significance of the tests for the selection of youth players to national teams are relative

Influence of Injection Strategies on Engine Efficiency for a Methanol PPC Engine

Partially premixed combustion (PPC) is one of several advanced combustion concepts for the conventional diesel engine. PPC uses a separation between end of fuel injection and start of combustion, also called ignition dwell, to increase the mixing of fuel and oxidizer. This has been shown to be beneficial for simultaneously reducing harmful emissions and fuel consumption. The ignition dwell can be

Literature Review on Dual-Fuel Combustion Modelling

In the search for low greenhouse gas propulsion, the dual fuel engine provides a solution to use low carbon fuel at diesel-like high efficiency. Also a lower emission of NOx and particles can be achieved by replacing a substantial part of the diesel fuel by for example natural gas. Limitations can be found in excessively high heat release rate (combustion-knock), and high methane emissions. These

Large Eddy Simulation of an Ignition Front in a Heavy Duty Partially Premixed Combustion Engine

In partially premixed combustion engines high octane number fuels are injected into the cylinder during the late part of the compression cycle, giving the fuel and oxidizer enough time to mix into a desirable stratified mixture. If ignited by auto-ignition such a gas composition can react in a combustion mode dominated by ignition wave propagation. 3D-CFD modeling of such a combustion mode is chal

Numerical Investigation of Methanol Ignition Sequence in an Optical PPC Engine with Multiple Injection Strategies

Methanol is a genuine candidate on the alternative fuel market for internal combustion engines, especially within the heavy-duty transportation sector. Partially premixed combustion (PPC) engine concept, known for its high efficiency and low emission rates, can be promoted further with methanol fuel due to its unique thermo-physical properties. The low stoichiometric air to fuel ratio allows to ut

A Coupled Tabulated Kinetics and Flame Propagation Model for the Simulation of Fumigated Medium Speed Dual-Fuel Engines

The present work describes the numerical modeling of medium-speed marine engines, operating in a fumigated dual-fuel mode, i.e. with the second fuel injected in the ports. This engine technology allows reducing engine-out emissions while maintaining the engine efficiency and can be fairly easily retrofitted from current diesel engines. The main premixed fuel that is added can be a low-carbon one a

‘One vast empire’ : China, progress, and the Scottish Enlightenment

Although references to China were few and fragmentary, the example of a ‘stationary’ East Asian Empire featured importantly in Scottish Enlightenment ideas about religion and political economy. David Hume considered whether the apparently long-flourishing system of Chinese government, grounded in rationally deduced deistic ethics, could provide an example for Western nations. Later in the eighteen

Hearing histories of Hammer Hill : Pop music as auditory geography

Focusing on artful, embodied listening as a method of analysing the emotional intensities of place, this article calls for academic geographers to listen to practitioners of nonacademic geography. It explores an ethical and methodological agenda for understanding how pop musicians have heard the world, and for taking them seriously as creative geographers who contribute sophisticated interpretatio

Dupuytren disease: Prevalence, treatment and outcome

Purpose To study the epidemiology of Dupuytren disease and evaluate treatment outcome of collagenase injections using a modified method.Patients and methods Paper I is a register-based study. From the general population of Skåne region (1.3 million) in southern Sweden, we identified all residents aged ≥20 years who had been diagnosed with Dupuytren disease during a 16-year period and identified tr

Geographies of the book (shop) : Reading women’s geographies in Enlightenment Edinburgh

This paper examines the place of women’s geographical reading in a centre of Enlightenment: Edinburgh, 1770–1810. It analyses two sets of booksellers’ records to identify key sites – women’s private libraries, Georgian domestic spaces, and women’s schools and boarding houses – in which women engaged with the geographical materials sold in the city’s bookshops: maps, globes, travel accounts, gazett

Effects of In-Cylinder Flow Structures on Soot Formation and Oxidation in a Swirl-Supported Light-Duty Diesel Engine

In this paper, computation fluid dynamics (CFD) simulations are performed to describe the effect of in-cylinder flow structures on the formation and oxidation of soot in a swirl-supported light-duty diesel engine. The focus of the paper is on the effect of swirl motion and injection pressure on late cycle soot oxidation. The structure of the flow at different swirl numbers is studied to investigat

Event-shape and multiplicity dependence of freeze-out radii in pp collisions at √s = 7 TeV

Two-particle correlations in high-energy collision experiments enable the extraction of particle source radii by using the Bose-Einstein enhancement of pion production at low relative momentum q ∝ 1/R. It was previously observed that in pp collisions at s = 7TeV the average pair transverse momentum kT range of such analyses is limited due to large background correlations which were attributed to m