Your search resulted in 243 documents. Displaying 25 entries per page.
The resistance of thermo and thermo-oil modified black poplar wood (Populus nigra L.) to Basidiomycetes fungi
2012 - IRG/WP 12-40585
The share of area taken by poplar tree species in Poland account for 2.0% of the area of state forests, 4.8% of national parks and for 2.3% in the privately-owned forests. It is shown and expected an increase in the share of poplar stands connected with plantation of fast growing trees. The poplar wood is not resistant to Basidiomycetes fungi, easy attacked by insects and in consequence is regarde...
A Fojutowski, A Kropacz, A Noskowiak
Mould growth on wood-based materials – a simulated in-service study
2012 - IRG/WP 12-20503
Ten different wood-based materials including preservative-treated wood, fire retardant-treated wood, modified wood, WPCs and untreated references of pine sapwood and spruce were placed in three different environments (an attic and two crawl spaces) for a period of 26 months. Mould growth was analysed at five to seven month intervals in an effort to map the growth development. The relative humidit...
G Bok, P Johansson, J Jermer
The effect on moisture content of water trapped in wood joints
2012 - IRG/WP 12-40613
To predict the service life of a structure, a model where the exposure of a structure is compared to its resistance can be used. Which exposure and resistance parameters that are relevant depend on which materials the structure consist of. This approach, with an exposure and a resistance parameter, is similar to the one used in structural engineering where a load (exposure) is compared to the bear...
M Fredriksson, L Wadsö, P Johansson
Activities of moulds on wood as a function of relative humidity during desorption and absorption processes
2013 - IRG/WP 13-10794
Three different types of indoor moulds: Penicillium brevicompactum, primary colonizer; Alternaria tenuissima, secondary colonizer and Trichoderma harzianum, tertiary colonizer, grown on wood were measured for their activities under different relative humidity levels. The activities were measured by isothermal calorimetry. The activities of the moulds changed with the change of the relative humidit...
Yujing Li, L Wadsö
Influence of a pulsed electric field on the growth of surface fungi
2013 - IRG/WP 13-10795
The colonization of mold and staining fungi are not only an aesthetical problem. Blue stain fungi are able to penetrate paint films. Maintenance of coatings on wood are time consuming and costly. A new approach uses a pulsed electric field (PLEOT) in order to protect wood against surface fungi. This technology is evaluated in non-sterile laboratory conditions on different coated and uncoated Scots...
M Starck, A Treu
Inhibitory extractives or nutrients? Mould growth on coated heartwood and sapwood of Pinus sylvestris and Gleditsia triacanthos
2013 - IRG/WP 13-10806
Sometimes mould fungi grow over weathered coated sapwood, whereas the coated heartwood is not colonised. Two factors may be responsible for these differences: Either the larger content of nutrients in the sapwood, or the content of biocidal extractives in the heartwood. In this study the factors for the difference in mould growth on coated heartwood and sapwood of Pinus sylvestris (Scots Pine) and...
D Lukowsky, N Buddruhs
The assessment by visual grading, change of color and ergosterol content ratings, the resistance to mould fungi of treated with wood preservative Scots pine sapwood
2013 - IRG/WP 13-20514
The filamentous (mould) fungi belonging to Ascomycetes, Deuteromycetes group are an cosmopolitan organisms which attacks wooden elements disfiguring them, dropping their value and causing environmental and health hazard. The fungi in a short time cause mainly disfigurement of wood does not effect on strength properties of wood, but with strong prolongation of duration of conditions favourable for ...
A Fojutowski, A Koziróg, A Kropacz
Service life evaluation of wood - an engineering approach
2013 - IRG/WP 13-20515
A performance-based service life design format based on climatic exposure on one hand and “biological wood resistance” on the other hand is presented in this paper. Important concepts are the introduction of limit states as well as reliable performance models for the biological processes, by which onset of deterioration can be predicted for arbitrary climate histories. Examples of applications...
S Thelandersson
Image analysis for mould and sapstain detection on wood
2013 - IRG/WP 13-20519
Laboratory tests for mould growth on wood products are time consuming and rely on visual assessments of specimens utilizing subjective rating systems. Accelerated laboratory methods are needed that can provide rapid, quantitative assessment of mould and sapstain growth on solid and composite wood products. Image analysis of scanned spore imprints from southern pine or oriented strandboard (OSB) sp...
C A Clausen, V W Yang
Method for determining the critical moisture level for mould growth on building materials
2013 - IRG/WP 13-20530
The natural conditions of relative humidity (RH) and temperature (T) in different parts of a building is rarely constant over time. Instead, RH and T often vary cyclically and may pose a risk of mould growth as these conditions are the two key environmental parameters that controls mould growth. Consideration to both humidity and temperature conditions and the susceptibility to mould in a material...
A Ekstrand-Tobin, P Johansson, G Bok
Surface energy characterization of thermally modified wood using inverse gas chromatography
2013 - IRG/WP 13-20532
The objective of this work is to characterize surface energetics of thermally modified wood. Such information may be useful for a better understanding and predictions of adhesion properties between the modified wood and other material systems, e.g. coatings, adhesives or matrices in composites. Inverse gas chromatography (IGC) was used to study the surface energy characteristics of thermally modif...
S Källbom, K Segerholm, D Jones, M Wålinder
Moisture distribution in glulam beams with natural cracks observed with CT Scanning before and after rain
2013 - IRG/WP 13-20534
The way cracks in outdoor wooden constructions affect durability is an interesting topic, since a certain amount of cracks can always be found naturally in wood and glued laminated wood. The question in this was, can cracks lead water into the wood and thereby increase the risk for decay and reduce strength and service life. Moisture balance, i.e., water absorption and water distribution were stud...
K Sandberg
Performance of biocide-free preservative-protective systems modified with organosilicon compounds
2013 - IRG/WP 13-30628
The objective of the research was to determine the influence of organosilicon compounds in preservative-protective systems on the selected properties of pine wood aimed for outdoor use. The investigations were made for biocide-free systems based on alkyd resin and natural oils modified with alkylalkoxy-, amino- and glycidoxysilanes. The special attention was paid on the influence of hydrophobic pr...
B Mazela, P Hochmańska, T Krystofiak
Preparation and characterization of activated carbon fibers prepared from liquefied wood
2013 - IRG/WP 13-40636
Activated carbon fibers were prepared from liquefied wood through stream activation. The effects of activation temperature and time on the microstructure and surface functional groups of the liquefied wood activated carbon fibers (LWACFs) were studied using analysis of burning behavior, X-ray diffraction, nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and SEM. The resu...
Wenjing Liu, Guangjie Zhao
Modelling the risk for mould growth on timber stored outdoors protected from rain
2013 - IRG/WP 13-20529
A mould resistance design (MRD) model was used to calculate the maximum duration of storage of timber outdoors under cover (protected from rain) before the onset of mould growth on the surface of wood. The prediction model is based on laboratory tests performed in constant and cyclic climates and were also confirmed against exposure tests in attics and crawl spaces. The prediction model presented ...
E Frühwald Hansson, S Bardage, S Thelandersson
Critical moisture levels and mould resistance of five different wood treatments
2013 - IRG/WP 13-30632
Mould resistance of five different treatments were tested using two methods, a recently
developed method for the determination of critical moisture levels of building materials (RHcrit),
and ASTM D3273-94. The critical moisture level method exposed samples at 22 °C and 98, 92,
86 and 82% relative humidity (RH) for 12 weeks. ASTM D3273-94 was performed at 29 °C and
about 95% RH.
Treatments c...
G Bok, P Johansson, A Ekstrand Tobin, S Bardage
Visualization of gold/silver nanostars in wood by surface enhanced Raman spectroscopy
2014 - IRG/WP 14-30653
Nanotechnology is a fast growing up-to-date technology and ventures expeditiously in the wood preservative market. However, there is still a huge lack of understanding about the interaction and incorporation of nanoparticles (NSs) in wood. Surface-enhanced Raman scattering (SERS) offers unique advantages as an analytical tool with a high selectivity and sensitivity without matrix interference. Her...
C Geers, L Rodríguez-Lorenzo, M Placencia Peña, P Brodard, T Volkmer, B Rothen-Rutishauser, A Petri-Fink
VOC-free remedial treatment agent on organic solvent basis with surface cleaning by photocatalysis using titanium dioxide
2014 - IRG/WP 14-40651
Due to the EU Regulations according to the harmonisation of the European market of biocidal products and the EU Regulations regarding emissions of volatile organic compounds in residential properties a new VOC free yet organic solvent based remedial treatment agent is introduced including a potential method to clean up the wooden surface of remaining biocides after a remedial treatment using photo...
H Ahl, J Fromm, P Jüngel, E Melcher, M Pallaske
The effect of UV irradiation on some technological properties of different polyurethane varnishes coated plywood panels from veneers dried at different temperatures
2014 - IRG/WP 14-40661
In this study, the effect of UV irradiation on some technological properties of three different polyurethane varnishes coated plywood panels produced from Scots pine (Pinus sylvestris L.) and Maritime pine (Pinus pinaster L.) veneers manuactured and dried at different temperatures was studied. Accordingly, 32°C log peeling temperature and three different veneer drying temperatures (110, 140 and ...
Ö Özgenç, C Demirkir, Ü C Yildiz, G Çolakoğlu
The role of hydrophobins in surface growth by the Blue Stain fungi Aureobasidium pullulans
2015 - IRG/WP 15-10837
Hydrophobins are small proteins found exclusively in filamentous fungi. These proteins are able to assemble spontaneously into amphiphilic monolayers at hydrophobic–hydrophilic interfaces. Hydrophobins have a diverse role, e.g. allowing the fungi to break through interfaces during aerial hyphae formation, sporulation, fruit body production and cell penetration. In this ongoing study, we are look...
J Stenbæk, L Riber, J Blæsbjerg Nielsen, C Møller Hansen, B Jensen
Short-term protection of palm wood against moulds and decay fungi by environment-friendly organic acids
2015 - IRG/WP 15-10843
Felled palm trunks are susceptible to fungi as long as their moisture content is above fibre saturation. During this period, it has to be protected against moulds and decay fungi. The study tested environmental-friendly organic acids for their protecting efficiency. Small samples of Date palm (Phoenix dactylifera) and Oil palm (Elaeis guineensis) wood were treated with weak organic acids and subse...
M Bahmani, O Schmidt
Development of a rapid screening method to determine the susceptibility to mould growth of novel construction and insulation products
2015 - IRG/WP 15-20562
Wood-based materials are commonly used in building construction/insulation as a replacement for solid timber. However, these materials are susceptible to microbiological growth and different environmental conditions influence the vulnerability of wood-based materials. Moulds are a common problem found within homes and cause aesthetic damage, health problems and can increase material vulnerability ...
B K Stefanowski, S F Curling, E Mansour, G A Ormondroyd
Acceptance levels of surface disfigurement - tolerance to defects of coated wood
2015 - IRG/WP 15-20564
Service life planning (PSL) has become an important issue in performance based building and substantial progress has been made in recent years. The role of predicting the aesthetical service life of wooden building components has been underestimated for quite long time but is recently attracting more and more notice. It is influenced by numerous factors such as discoloration, fading, flaking, crac...
C Brischke, P Kaudewitz
Mould growth on spruce claddings and the effect of selected influencing factors after 4 years of outdoor testing
2015 - IRG/WP 15-30671
Norway spruce (Picea abies) is the most frequently chosen wood species as claddings in façades in Norway, and is used both coated and uncoated. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more often growth of mould and blue stain fungi is the main challenge. A field test with synchronous monitoring of relative humidity, air temperature, material temperature and wood moisture content in Norway spruce claddings has been performed in southern Norway as part of the ClimateLife project. Visual evaluation of blue stain and mould growth according to EN 927-3 was performed, and evaluation data after 46 months exposure is presented. The objectives were to study the effect of 1) environment, 2) cardinal direction and 3) colour of the coated surface on growth of blue stain and mould fungi and to study the variation in relative humidity, air temperature, wood moisture content and material temperature. After 46 months exposure, the red coating system had generally the lowest mould ratings and the uncoated claddings had the highest. Of the white coloured claddings the ones facing south had lower mould ratings than those facing north, but the opposite were found for red coloured claddings. The relative humidity was higher in front of claddings exposed northwards and in a shaded environment compared to an open environment against south. In an open environment red coloured claddings had the lowest wood moisture content and highest material temperature, and red coloured claddings against south had the highest maximum material temperature.
L Ross Gobakken, G I Vestøl
The resistance of composite boards protected with azole and inorganic nanoparticles to basidiomycetes and moulds
2015 - IRG/WP 15-40688
This paper presents a study on the resistance of wood composite boards, glued with silicone adhesive and obtained from chips of Scots pine Pinus silvestris L. and willow Salix viminalis L., to basidiomycetes and mould. The boards were protected in the production processes with fungicides based on metal nanoparticles, as well as on derivatives of 1,2,4-triazole, benzimidazole, and thiazole. The bio...
J Zabielska-Matejuk, I Frąckowiak, A Stangierska