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Popular Abstract in Swedish Kavitation uppstår när trycket är så lågt så att vätska övergår till gas och det är ett problem i många vattenkraftverk på grund av att det kan försämra turbinverkingsgraden samt skada närliggande fasta ytor. Denna avhandling behandlar de numeriska svårigheter som man måste komma tillrätta med för att kunna datorsimulera kavitation i vattenturbiner. Dessa beror på den tCavitation is a problem in many hydroelectric power plants since it can cause adverse effects on performance and damage to nearby solid surfaces. The concerns of this thesis are the numerical aspects of flow simulations in cavitating hydraulic turbines which contain several difficulties: turbulent and complex flows, steady and moving parts of the geometry, bubble transport and cavitation developme

Paper wrappers and paper bindings have been used to preserve written and archival documents of all kinds. In the manuscript collection of Ericsberg (National Archives, Sweden) we find many examples of how written material was gathered and protected by simple paper bindings. Paper bindings are used as sketchbooks, for writing and calculating, as diaries, and as notebooks of administrative and econo

This thesis critically examines the world of NGOs in contemporary Nicaragua, and suggests connections between the current development 'boom' and the emergence of a materially privileged local development elite, which by means of its cultural and economic capital are in a position to exiercise considerable power in relation to other less powerful strata of the population. It is based on fieldwork c

Sugar beet (Beta vulgaris L.) plants injected with Cercospora beticola Sacc. as well as non-infected plants were grown under visible light with or without ultraviolet-B (UV-B, 280-320 nm) radiation for 40 days. An interaction between UV-B radiation and Cercospora leaf spot disease was observed, resulting in a large reduction in leaf chlorophyll content, dry weight of leaf laminae, petioles and sto

This study describes the removal of polycyclic aromatic hydrocarbons (PAHs) from creosote oil contaminated soil by modified Fenton's reaction in laboratory-scale column experiments and subsequent aerobic biodegradation of PAHs by indigenous bacteria during incubation of the soil. The effect of hydrogen peroxide addition for 4 and 10 days and saturation of soil with H2O2 on was studied. In both exp

The formation of exopolysaccharides (EPS) by Pediococcus damnosus strain 2.6 was investigated in two different high P-glucan suspensions of oat (OBC) and barley (BBC). Bacterial growth was confirmed by measuring pH, colony forming units (cfu), viscosity and ropiness during growth. Growth and an increase in viscosity of the beta-glucan suspension based on oat were observed whereas only a minor grow

Flux reductions experienced during ultrafiltration are due either to concentration polarization or fouling. It is usually difficult to distinguish between these two phenomena, but by using a turbulence-promoting module it is possible to determine the reversibility of a flux reduction, and thus distinguish between concentration polarization and fouling. By using a turbulence-promoting module, it is

There are few studies on the microclimate and human comfort of urban areas in hot dry climates. This study investigates the influence of urban geometry on outdoor thermal comfort by comparing an extremely deep and a shallow street canyon in Fez, Morocco. Continuous measurements during the hot summer and cool winter seasons show that, by day, the deep canyon was considerably cooler than the shallow

Objective: To study antibodies to cyclic citrullinated peptides (anti-CCP) and rheumatoid factor in patients with active, severe extra-articular rheumatoid arthritis (ExRA) compared with controls without ExRA. Methods: 35 consecutive patients with severe ExRA manifestations according to predefined criteria were studied. 70 patients with rheumatoid arthritis, but no ExRA manifestations, individuall

In 1993-1998 the lichen flora of Stora Karlso and Lilla Karlso was surveyed. These two nearby islands are situated outside the west coast of Gotland, Sweden, in the Baltic Sea. In all, 355 species were found, including three lichenicolous fungi. Two species are new to Sweden, viz. Lepraria flavescens and Placynthium lismorense. Both were found on limestone. The number of species according to habit

Multi-Input Multi-Output system has been one of the hot technologies for future wireless communications, since it can increase the capacity (coverage or link quality in other senses) at no cost in frequency spectrum. This doctoral thesis investigates improvements to MIMO decoding algorithms and presents VLSI implementation results. The main contributions consist of four algorithms and three VLSI i

Recently, international study groups have collected mutations for X-linked immunodeficiency diseases. In this issue of Immunology Today five databases are reported, comprising mutations from over 1000 patients, facilitating detailed analysis of genetic, immunological, biochemical and structural parameters.

During the last 5 years the potential for applications of semiconductor nanowires has grown rapidly via the development of methods for catalytically induced nanowire growth using the, so-called vapor-liquid-solid (VLS) growth mode. The VLS method offers a high degree of control of parameters such as position, diameter, length and composition, including the realization of atomically abrupt heterost

Squamarina scopulorum, until now only known from Norway, is reported from one locality in Padjelanta National Park in northern Sweden. It was found growing on a S-facing rock surface in the low alpine zone on the mountain Unna Djidder near Staloluokta.