Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2008
Abstract
New restrictions draw governments, industry and research towards new and environmental benign wood protective agents. These agents often come from a natural source, and are also a waste product. One of these is chitosan. Chitosan is a derivative from chitin, mainly found in the exoskeleton of crustacean. Some research has been conducted on chitosan and wood. Chitosan has earlier proven good antifungal effectiveness, but to achieve a good protection, a 5 % concentration is needed, which makes the end product quite expensive. In recent research, a way to make chitosan treated wood hydrophobic has been invented. The objective of the research presented in this paper, is to describe the effectiveness of the following compounds: Chitosan, chitosan/copper, chitosan/boron and chitosan/Scanimp (a commercial wood preservative). Results show that chitosan works well alone, but has a fixation problem. Chitosan and boron give good fixation, and reduced amounts of chitosan and together give good protection against wood destroying fungi. The fire protection agents are promising, but needs higher concentration and/or better fixation to give a sufficient protection against wood destroying fungi
Authors
Erik LarnøyAbstract
To evaluate the decay resistance of wood, treated or untreated, for hazard classes 3, 4 and 5, the mass loss due to fungal exposure needs to be calculated. The standards for calculating mass loss in wooden test samples (i.e EN 113 and ENV 807) require that the samples used in the test are pre-dried to 0 % moisture content, m0, for determination of the initial dry mass. The standards describe that the samples should be dried at 103±2°C for 18 hours. When drying wood samples to 103 °C the samples are altered. Literature describes that extractives are influenced at temperatures as low as 60 °C, and redistribution and/or evaporation of these, will change the characteristics of the wood samples...
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No abstract has been registered
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Abstract
The variations on the ratio of filling (RoF) were investigated on Norwegian grown Scots pine (Pinus sylvestris). The samples were taken from 10 different stands in south-east Norway, and treated with furfuryl alcohol and a copper-containing wood preservative. Both within tree variations, between tree variations and variations between stands were investigated for significant differences. Factors like horizontal and vertical positioning of the stem, annual ring width, density, tree height, tree age and latitude were tested. Samples of 20 x 20 x 60 mm were impregnated with a mild treatment scheme to avoid full penetration, which made it possible to distinguish the RoF. A significant variation was found between copper impregnated a furfuryl treated samples, favouring the copper impregnated samples. Within tree variations show a positive significance of the first log compared to the other logs, and a higher RoF in younger sapwood. The latitude of the stand gave a strong correlation, favouring southern stands.
Abstract
An easier penetrability and a more even uptake of wood protection agents is aimed for the two most common wood species in Europe, namely Norway spruce (Picea abies) and Scots pine heartwood (Pinus sylvestris), particularly when there is a great difference in absorption behavior of sapwood and heartwood. Microwave conditioning can improve permeability, reduce density and heat conductivity and change dimensional stability of wood. It could also improve the permeability of refractory wood species. This study deals with the evaluation of different parameters of a microwave treatment and their influence on the penetrability of water during dipping and impregnation of Scots pine heartwood and Norway spruce. Microwave irradiation lead to an increased water uptake after a submersion test, and after vacuum and pressure impregnation of the tested samples. This effect was more pronounced for Scots pine heartwood samples than for spruce wood samples. A short process with high microwave energy is recommended in order to reduce the development of large cracks but to increase the sorption behavior due to small checks in wood.
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No abstract has been registered
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No abstract has been registered
Authors
Tor MykingAbstract
An international EU/Interreg III Kolarctic project `Development and implementation of an environmental monitoring and assessment program in the joint Finnish, Norwegian and Russian border area`, was carried out during 2003–2006 as a joint undertaking between Norwegian, Finnish and Russian research institutes and environmental authorities. The aim of the terrestrial ecosystem sub-project of the Pasvik project was to develop and implement a monitoring and assessment programme for terrestrial ecosystems in the joint Finnish, Norwegian and Russian border area...
Abstract
Harmonization was achieved by carrying out joint sampling and assessment exercises at selected sites, inter-laboratory ring tests for the chemical analyses of deposition, plant and soil material, and by drawing up data compilation, data analysis and reporting guidelines and templates for the researchers working in the three countries.