Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2010
Sammendrag
Development in surface mould growth on painted/unpainted wooden claddings and acting climatic factors were investigated over a period of 3 years. Eight wood substrates, including modified, preservative-treated and untreated wood, were tested in combination with three types of paint: (1) water-borne alkyd modified acrylic paint without fungicide; (2) solvent-borne alkyd paint without fungicide; and (3) ICP (internal comparison product). One set of samples was exposed unpainted. The samples were tested according to a modified version of EN 927-3. A logistic regression model was fitted to the data. The degree of mould growth varied with exposure time, coating typology, wood substrate, temperature and relative humidity. Exposure time and coating typology contributed most to the model. After 3 years of outdoor exposure unpainted panels and panels coated with solvent-borne paint without fungicide had more mould growth than panels coated with ICP and water-borne paint without fungicide. Unpainted oil/copper–organic preservative-treated claddings had higher resistance to mould growth than other unpainted wood substrates. Coated untreated pine and coated acetylated pine were more susceptible to mould growth than other coated wooden substrates.
Sammendrag
Microbial disfigurement of coated wooden surfaces is considered a major maintenance concern and will shorten the aesthetic service life of wooden facades. The effect of the physical surface structure of a paint film when applied on wood may have an impact on the susceptibility to mould growth. Six model paints were formulated to give the following physical surface structures: glossy, matt, soft, hard, hydrophobic, and a film with air inclusion. The model paints and a standard paint, with and without fungicide, were applied on panels of Norway spruce (Picea abies L Karst.) and exposed outdoors for nearly three years according to a modified version of EN 927-3. A logistic regression model was fit to the data, and the degree of mould growth varied with exposure time and type of paint. Hard model paint was significantly more susceptible than the other model paints and had a performance close to the standard paint without fungicide. Soft model paint provided the best performance, with the least mould growth. Temperature, relative humidity, and precipitation did not significantly contribute to the model. (C) 2010 Elsevier Ltd. All rights reserved.
Forfattere
Per Otto Flæte Gry Alfredsen Kristian Bysheim Øyvind Eriksen Anders Qvale Nyrud Birger VenneslandSammendrag
Roundwood timber is raw material for numerous products. Wood based products are generally recognised as favourable regarding energy consumption and greenhouse gas (GHG) emissions. Several studies have shown that the net CO2 emissions can be reduced by using biofuels harvested from forests to substitute fossil fuels, and by using wood for building materials. Energy use and GHG emissions associated with producing roundwood can be influenced by a broad range of factors, such as silvicultural practice, topography, applied technology, forestland ownership, industrial structure, etc. This emphasizes the importance of using representative data for energy use and GHG emissions when calculating environmental impacts. The aim of this study was to investigate the embodied energy and life cycle GHG emissions of industrial softwood sawlogs in Norway, covering the production chain from tree seed to log yard. Analyses were based on activity data for the Norwegian forest sector for the year 2007. The results showed that the embodied energy and GHG emissions were low compared with the energy and CO2-equivalents stored in the roundwood (about 2%). The findings from this study can be used to inform future decisions on processes in forestry that should be focused on when planning actions to reduce energy consumption and GHG emissions. Additionally, as roundwood timber is raw material for numerous products the results can be useful when preparing documentation of environmental impacts, such as environmental product declarations, which are increasingly demanded by the market.
Sammendrag
Traditional wood preservatives based on biocides are effective against wood-deteriorating organisms because of their toxicity. By contrast, modified woods are non-toxic by definition. To investigate the efficiency of various wood modifications, quantitative real-time polymerase chain reaction (qPCR) was used to profile the DNA amounts of the white-rot fungus Trametes versicolor (L.) [Lloyd strain CTB 863 A] during an 8-week-long growth period in treated Pinus sylvestris (L.) sapwood. The studied wood was modified by acetylation, furfurylation, and thermal treatment. The traditional wood preservatives bis-(N-cyclohexyldiazeniumdioxy)-copper (Cu-HDO) and chromated copper arsenate (CCA) were used as references, whereas untreated P. sylvestris (L.) sapwood served as a control. The maximum levels of fungal DNA in native wood occurred at the end of the experiment. For all wood treatments, the maximum fungal DNA level was recorded after an incubation period of 2 weeks, followed by a decline until the end of the trial. For the preservative-treated woods, Cu-HDO showed the lowest level of fungal DNA throughout the experiment, indicating that exploratory hyphal growth is limited owing to the phytotoxicity of the treatment. The other treatments did not inhibit the exploratory hyphal growth phase. We conclude that qPCR studies of hyphal growth patterns within wood should provide a powerful tool for evaluating and further optimizing new wood protection systems.
2009
Sammendrag
New environmental benign wood protection agents often come from natural resources, and are sometimes a waste product. Chitosan, a derivative from chitin which is among other sources a by-product from the shellfish industry, is tested as well as known wood protection agents and their synergetic effect with chitosan. The objective of the research presented in this paper, is to describe the leaching properties of the following compounds: Chitosan, chitosan/copper, chitosan/boron and chitosan/ScanImp (a commercial wood preservative). A leaching procedure was performed on treated Scots pine sapwood samples. The four solutions have also been tested with and without post treatment. A new effective fire preservative has been included in the test. Common wood preservatives have been tested as references. The combination with chitosan did improve the fixation of the wood protection agent ScanImp. Furthermore, the post treatment of the chitosan treated samples did significantly reduce the leaching of glucosamine and to some extend also the leaching of boron.
Sammendrag
The durability of wood in exterior use is limited by to climatic factors and wood deteriorating organisms. The natural durability of the Nordic wood species is generally regarded as low, and for e.g. decking and use in soil contact wood protection is needed. Within the last years, new non-biocidal treatments, like wood modification systems, have been developed to improve the biological resistance of wood. For information about the decay resistance of untreated and modified wood, natural outside exposure is necessary. European standard EN 252 is the main field test method for use class 4. In use class 3 the need of new or improved test setups has been put forward. Traditionally evaluation of field trials has mainly been based on visual evaluation and pick-test. However, to get in depth knowledge about: 1) different field trial methods and 2) fungal colonization of new wood protection systems, additional assessment methods can be used. Hence, comparative studies are needed.....
Sammendrag
Denne oppdragsrapporten er utarbeidet for å få en oversikt over energipotensialet fra skogen i Norge. Grunnlaget for dataene er Landskogtakseringens materiale samt Marklunds funksjoner for beregning av greiner, topper og stubber.
Forfattere
Simen GjølsjøSammendrag
Det er ikke registrert sammendrag
Sammendrag
One of the biggest drawbacks of using European native wood species as a construction material is its tendency to degrade by fungal attack. This has lead to the development of different systems for wood preservation. Many of these systems suffer the disadvantage that they contain biocides, which can leach from the wood into the environment and damage organisms. In this project ten silanes, 3-(2-Aminoethylamino)propyltrimethoxysilane, 3-[2-(2- aminoethylamino)ethylamino]propyltrimethoxysilane, 3-Aminopropyltrimethoxysilane, Diethoxydimethylsilane, Dodecyltriethoxysilane, Hexadecyltrimethoxysilane, NTrimethoxysilylpropyl- N,N,N-trimethylammoniumchloride, Octyltriethoxysilane, Octyltrimethoxysilane and Phenyltrimethoxysilane, have been investigated for their ability to increase the hydrophobicity of wood and decrease shrinking and swelling, and thus increase its ability to withstand attack by fungi. In the initial phase of the project two solvents, ethanol and water were investigated to find out which of these that gave the best result for surface modification with silanes. The results showed that water as solvent gave a surface with higher hydrofobicity than when ethanol was used as solvent....
Sammendrag
Det er ikke registrert sammendrag