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Controlled Trapping in Laser Wakefield Accelerators

Experimental studies of laser-driven acceleration of charged particles, in particular electrons and protons, are described in this dissertation. Tightly focused femtosecond laser pulses with intensities exceeding 1018 W/cm2 were used to accelerate charged particles to high energies over distances of a few millimeters. Although the transverse fields of such laser pulses are sufficient to directly a

Monitoring biodiversity in cultural landscapes: development of remote sensing- and GIS-based methods

Kulturlandskapet är starkt knutet till människan och hennes aktiviteter. Flera tusen år av samspel mellan människa och natur har skapat landskap som definierar levnadsvillkoren för en mångfald av arter. Men när samhället förändras, förändras även kulturlandskapet. De forna årtusendenas långsamma och gradvisa förändringar har accelererats av människans teknologiska framsteg. I södra Sverige har jorIn this thesis, I explore the relationships between structural and compositional landscape properties, and species diversity, using remotely sensed data on a variety of spatial scales. The thesis shows that increased landscape heterogeneity, measured using environmental and spectral variables that were used both separately and combined, is generally positively related to plant species richness. I

The color of child survival in Colombia, 1955-2005

Objective(s): Colombia has the third largest black population in the Americas after Brazil and the USA. In 2005 mortality rate under 5 in Colombia was 21.5 per 1000, with a reduction of 82 per cent between 2005 and 1960. That rate is not in line with rates for Cuba (6.8), Chile (9.1) or Costa Rica (10.4). Here we aim to provide evidence that a further reduction of child mortality relates to the un

Cascades of green: A review of ecosystem-based adaptation in urban areas

Climate change impacts increase pressure on challenges to sustainability and the developmental needs of cities. Conventional, “hard” adaptation measures are often associated with high costs, inflexibility and conflicting interests related to the dense urban fabric, and ecosystem-based adaptation (EbA) has emerged as a potentially cost-efficient, comprehensive, and multifunctional approach. This pa

Perceptions of the ecosystem services concept: Opportunities and challenges in the Swedish municipal context

A current focus of ecosystem services (ES) implementation is on the municipal level of government where international and national legislation and policies have to be translated into practice. Given this focus, an understanding of perceptions within municipalities of the ES concept is crucial to support the implementation process. Against this background, this paper examines the perceptions of Swe

Experimental Investigations of Combustion Chamber Heat Transfer in a Light-Duty Diesel Engine

This work concerned experimental studies of heat transfer in a light-duty diesel engine. Combustion is affected by several parameters, such as pressure, engine speed, mass of injected fuel and in-cylinder gas flow. These parameters are in turn affected by the combustion chamber geometry and fuel spray characteristics. At high load the exhaust heat was increased more than at high engine speed. Swir

Iron Carbonyl Clusters as Proton Reduction Catalysts

En utveckling av den s. k. väte-ekonomin, där vätgas (H2) används som energibärare, skulle – rent teoretiskt – kunna lösa människans energiproblem då vatten skulle kunna användas som bränsle. För att nå detta mål krävs dock väsentlig teknologisk och vetenskaplig utveckling. Ur ett rent vetenskapligt perspektiv, måste bl a (energisnåla) kemiska metoder att skapa stora mängder vätgas utvecklas. MångAbstract – The mixed-valence triiron complexes [Fe3(CO)7-x(PPh3)x(µ-edt)2] (x = 0, 1, 2; edt = SCH2CH2S) and [Fe3(CO)5(κ2-diphosphine)(µ-edt)2] (diphosphine = dppv, dppe, dppb, dppn) have been prepared and structurally characterized. In comparison to the diiron complex [Fe2(CO)6(µ-edt)], [Fe3(CO)7(µ-edt)2] catalyzes proton reduction at 0.36 V less negative potentials, which is a significant energe