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.
2007
Sammendrag
The effectiveness against soft rotting micro fungi and other soil inhabiting micro-organisms was tested according to ENV 807 using different treated Scots pine sapwood and beech wood samples. The treatments differed in basic material, solvent, depolymerization agent, viscosity and post treatment. The chitosan treated Scots pine samples showed improved performance against soft rot, whereas a large amount of untreated pines sapwood samples failed during the test. The different chitosan treatments showed only slight differences in performance during the test.Further results of ongoing field tests should give more information about the life performance of the treated samples.
Sammendrag
Furfurylated wood has shown to have promising properties for a wood modification agent during the last years. In this paper, an alternative curing method for furfuryl alcohol modified pine sapwood by means of microwave radiation was investigated. Different process parameters of microwave treatment such as output power, exposure time to microwave radiation, initial wood moisture content and evaporation during treatment, were tested. The weight percent gain of pine wood samples due to polymerised furfuryl alcohol was investigated by means of thermo gravimetric analysis. Leaching of furfuryl treated and differently cured samples gave information about the degree of fixation. No distinct influence of initial moisture content could be stated. A slight tendency of improving the degree of fixation by increasing the consumption energy of wood samples due to microwave energy was found. Changing the evaporation ability of samples during microwave treatment by using plastic foil had no distinct influence. Fixation of furfuryl alcohol could be improved by microwave treatment, and a degree of fixation above 90 % was calculated. However, the fixation was lower than in oven cured samples.
Sammendrag
Skog og landskap utførte i 2005 studier av uttak av virke i kulturlandskap. Studiene ble gjort i Arendal kommune. En utfordring med å avvirke trær med små dimensjoner er å finne kostnadseffektive metoder. Bruk av hogstmaskin påmontert et akkumulerende klippeaggregat kan være en effektiv måte å rydde kulturlandskapet på. Et akkumulerende klippeaggregat er et aggregat som feller og kan samle flere trær før trærne legges i haug. Det kan også kappe trærne. Når de felte trærne ligger i haug, er det lettere å få til en rasjonell transport til bilvei. Råstoffet kan brukes til ulike formål, som f. eks. bioenergi, plater, fyllmasse i vei.
Sammendrag
Over hele landet kan vi observere at tidligere dyrket mark og åpne områder langsomt, men sikkert dekkes av busker og trær. Endringstakten synes å være størst i kyst- og fjordlandskapene på Vestlandet og i Nord-Norge samt i kystsonen på Sørlandet. Men også fjellstrøk med tidligere sæterdrift, ravineområder på Østlandet og i Trøndelag samt innlandsbygdene, gjennomgår vegetasjonsendringer. Denne endringen skjer hovedsakelig som en følge av redusert husdyrbeiting. Forandringer i landskapene kan bety tap av kultur- og naturverdier, men det kan også gi rom for ny og spennende bruk og næringsaktivitet.
Forfattere
Simen GjølsjøSammendrag
Forbruket av bioenergi i Norge i dag er om lag 16 TWh per år, og vi bruker i all hovedsak trevirke. Hvis Norge skal oppfylle EU sine mål for bioenergi, vil forbruket utgjøre ca. 40 – 50 TWh per år. Bio energi kan utnyttes til varme, strøm og drivstoff. Av de ulike bioenergibærerne, vil trevirke utgjøre det største kvantumet i Norge. For å oppnå optimal energiutnyttelse av trevirke, er det viktig med riktig brenselskvalitet. Et av de viktigste kvalitetskriteriene for biobrensel er fuktighet.
Sammendrag
The aim of this study was to use Energy-Dispersive X-ray Spectroscopy (EDS) to localize chitosan in the cell wall of chitosan impregnated Scots pine. It is of both general and specific interest to investigate the concentration of chitosan in the wood matrix to gain further knowledge and understanding of chitosan as a wood protective system.After deacetylation, chitosan was re-acetylated with chloroacetic anhydride to achieve a covalent bonding of chloride to the chitosan polymer. Chloride labeled chitosan was measured by EDS using a Scanning Electron Microscope (SEM) and described in apparent concentration of chloride. Analysis for free chloride anions was tested by dialysis and ion chromatography.There was a significant correlation between the molecular weight of chitosan and the apparent concentration of covalent bonded chloride to the chitosan polymer. High molecular weight chitosan showed a better interaction with the cell wall structure than low molecular chitosan.
Sammendrag
Furfurylated wood is an environmentally friendly, chemically treated, wood product with improved characteristics. Quality control of furfurylated wood is still performed manually by subtracting the initial weight of a treated sample from its final weight, then dividing the result by the initial weight. Expressed as a percentage, this results in a value that represents the weight percent gain (WPG) of the treated sample and thus the degree of modification. The major disadvantage of this quality control method is that the production parameters are needed to determine WPG, since the initial weight cannot be deduced from a treated wood sample. In this paper the use of ThermoGravimetric Analysis (TGA) is presented as a potential quality control method for furfurylated Scots pine (Pinus sylvestris L.). The technique is independent of production parameters and, therefore, enables third parties to determine the WPG of any furfurylated wood product. Three validation trials have been performed with the same validation samples, but varying TGA settings and with different Partial Least Square regression models (PLS-models). Although the method needs further improvement, it has shown good accuracy and precision. Therefore, it is con
Sammendrag
Furfurylated wood (wood modified by furfuryl alcohol) has over the last years gained marked shares from both tropical wood and conventional preservative treated wood and this has, in turn, generated several research projects concerning process development. The impregnation of spruce is well known from literature to be a difficult task. Furthermore, the sapwood of Scandinavian grown Scots pine is also known to be difficult to fully impregnate from time to time. The primary objective of the study was to evaluate whether the Oscillating Pressure Method (OPM) could be used to impregnate green and dry Norway spruce wood (Picea abies) with a Furfuryl alcohol (FA) - mixture. The secondary objective of the study was to evaluate if OPM could improve the penetration of FA in Scots pine (Pinus sylvestris) as compared to conventional full cell (Bethell) treatment. Impregnation tests were carried out on boards and planks as well as 300 mm and 500 mm clear wood samples. Samples were removed for MC measurement and the initial weight of the test samples was determined. Four different impregnation schemes were tested. The results indicate that Norway spruce can be impregnated by the OPM method to produce a protective shell of treated wood around a core of untreated wood. The penetration in Spruce showed great variation between different boards and between different parts of the individual boards. This is in part expected, but can also be caused by uncontrolled pre drying of the test material which was stacked uncovered after sawing. For Scots pine, the OPM improved the penetration of both sapwood and, to some extent, the outer heartwood.
Sammendrag
The objective was to evaluate whether Lowry-impregnation of Scots pine with FA100-mix, instead of the FA40-mix, would lead to similar or slightly higher WPGs and to investigate any potential changes in penetration pattern. The results indicate that the penetration was better, also penetrating the outer zone of the heartwood. Furthermore, it was possible to reduce the WPG-levels for pine down to 50-70% (corresponding to PFA retentions of 260- 315 kg/m³) from 120% (approx. 550 kg/m³) with full-cell impregnation using FA100-mix. Using the Lowry process with FA100-mix would probably be a possible treating schedule for products aimed for use in ground contact. The reduced content of hygroscopic salts in the furfurylated wood product would also further reduce hygroscopisity compared with FA-40 mix. However, more trials are needed in order to optimize penetration while still keeping the final WPG low.
Sammendrag
Trevinduers kvalitet og levetid er avhengig av en rekke faktorer. Kvalitet på trevirke er en slik faktor og utgangspunktet for all vindusproduksjon. En state of the art rapport fra Norsk institutt for skog og landskap belyser og diskuterer trekvalitet i et vindusperspektiv.