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An amorphous, colorless, and highly transparent polymer containing boron atoms in its branched chain architecture was synthesised from boron trioxide, poly(ethylene glycol) (PEG) and methoxy end-capped PEG. Electrolytes based on this polymer and different concentrations of lithium perchlorate (LiClO4) were prepared and characterised by impedance spectroscopy, calorimetry and thermogravimetry. The

To study the effect of different injection timings on the charge inhomogeneity, planar laser-induced fluorescence (PLIF) was applied to an operating engine. Quantitative images of the fuel distribution within the engine were obtained. Since the fuel used, iso-octane, does not fluoresce, a dopant was required. Three pentanone was found to have vapor pressure characteristics similar to those of iso-

Proton-Induced X-ray emission analysis (PIXE) constitutes a method for trace element analysis characterized by multielemental capability, detection limits in the low ppm-range and size resolution down towards a micrometre. In applications where the sensitivity of the Electron-Induced X-ray Emission (EIXE) analysis is not sufficient and where a spatial resolution not better than a few micrometres i

Four different non-nuclear industries have been investigated regarding the presence of radioactive elements, with the focus on natural radioactivity. The aim of the studies was to investigate the flow of radionuclides in the processes and/or to estimate doses to exposed workers. The first industry investigated was phosphate processing in the manufacture of dicalcium phosphate (DCP), which is used

Popular Abstract in English “We are not free in this area.” This is what the iNduna, a traditional leader at KwaDapha, shared with me when we first met in August 2011. KwaDapha is a small rural community at Bhanga Nek, Kosi Bay, in northern KwaZulu-Natal/Maputaland – one of the most scenic areas on the South African coastline. Kosi Bay falls within the Coastal Forest Reserve section of the iSimaIn the past several decades under a growing influence of ecological modernisation, various assumed ‘win-win’ approaches to protected area conservation and poverty alleviation have been introduced all over the world, especially in resource-rich developing countries. Yet protected area conservation is an inherently political process, and the goals are often not achieved. There are concerns about com

Cerium dioxide, or ceria, is a chemically stable oxygen ion conducting material with a capacity to store and release oxygen, and is therefore extensively used in combustion catalysts. The Cu-Ce-O system has been identified as one of the most active catalysts for the combustion of carbon monoxide. To study the catalytic oxidation of CO, we have synthesised model CuO_x/CeO₂ cata

Popular Abstract in Swedish I början 1990-talet upptäcktes att det var möjligt att syntetisera så kallad mesoporös silika. Upptäckten fick stor uppmärksamhet då materialen har ett flertal intressanta egenskaper som inkluderar ett stort antal porer med väldefinierad diameter, jämn partikelstorlek och möjligheten att påverka dessa och andra egenskaper. I den här avhandlingen har det mesoporösa siliSeveral aspects related to the mesoporous silica material SBA-15 have been studied through the use of a wide range of experimental techniques, including low voltage high-resolution scanning electron microscopy, small angle X-ray scattering and nitrogen sorption. This work contains three parts, which are in many ways overlapping. The first part deals with the formation of SBA-15, it is found that a

In the emerging Delay Tolerant Networks (DTNs) content dissemination platform, mobile nodes opportunistically exchange content as they meet, with the intent of sharing content among nodes with common interests. During a meeting, nodes can exchange both content of direct interest to themselves as well as content that is of interest to a larger set of nodes that may be encountered in the future. The

In order to elucidate the composition of the female sex pheromone of the northern (beech) winter moth, Operophtera fagata Scharf. (Lepidoptera: Geometridae), ovipositor extracts of unmated, calling females were analysed by gas chromatography with simultaneous electroantennographic and flame ionization detection (GC-EAD/FID). Male antennal responses indicated three active components, two of which h

A mathematical model for through drying of paper at constant pressure drop was developed. The model is based on physical properties; hence, basis weight, pressure drop, drying air temperature, pore size distribution, initial gas fraction, and tortuosity are important input parameters to the model. The model was solved for different combinations of the variables basis weight, drying air temperature

Hydrologists are often faced with the problem of missing values in a precipitation-runoff process database to construct runoff prediction models. They tend to use simple and naive methods to deal with the problem of missing data. Thus far, the common practice has been to discard observations with missing values. In this paper, we present some statistically principled methods for gap filling and di

The irritation response of the rabbit eye to trigeminal nerve stimulation, which includes a breakdown of the blood-aqueous barrier (BAB), seems to be due to the release of substance P (SP) and calcitonin gene-related peptide (CGRP). In order to assess the relative importance of these two peptides for the barrier effect, and the role of arachidonic acid metabolites (AAM) in the response, we have st

Popular Abstract in English In Mozambique, many wild fruit species occur naturally in forest environments. Most of the wild fruits are consumed fresh because of their short shelf-life when ripe. Forests play an important role in rural communities as a source of food and medicinal and social/cultural services and also provide a source of income when fruits are sold at local markets. Some parts of MVangueria infausta (African medlar) is a wild fruit found in southern and central Mozambique. The ripe fruit has a leathery skin enclosing three to five seeds embedded in a soft pulp that tastes like apple. It plays an important role in the diet of the rural population and has the potential for commercial use. The fruit is mostly eaten fresh, and sometimes mixed with porridges, but in some parts

Popular Abstract in Swedish I ett väderälskande land som Sverige finns det väl ingen som inte är bekant med den väderkarta som ger oss information om hur prognosen för den närmaste tiden ser ut? Många av oss tittar dagligen på väderrapporten och låter den hjälpa oss att bestämma om vi ska cykla eller ta bussen, sätta på grillen eller laga mat i ugnen. Genom enkla visualiseringar i form av sol, regWith the aid of modern computer technology the application of visualization and simulation technology has become increasingly important in today’s society. Through computer modelling it is possible to experience, understand and explore environments, systems or objects in two or three dimensions and to see, hear and sometimes tangibly feel them. It may be environments or objects that do not yet exi

Aqueous solutions of a particular type of the nonionic cellulose derivative ethyl(hydroxyethyl)cellulose (EHEC) may form thermoreversible gels in the presence of ionic surfactants. Low-viscous solutions can be transformed to clear, stiff gels as the temperature is increased. The gelation may occur at temperatures as low as 30-35 °C which could make the systems interesting for applications, e.g. as

Accessibility in public outdoor environments is an important issue for persons with reduced functional capacity, for example older persons, and is also crucial for older pedestrians’ safety. The aim of the paper is to evaluate the importance and satisfaction of accessibility issues in public outdoor environments the year around as perceived by older persons (65 years old and above). Within two bef