Your search resulted in 145 documents. Displaying 25 entries per page.
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
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
Surface moulds and staining fungi on acetylated wood – effect of increasing acetyl content
2013 - IRG/WP 13-10797
Wood used in outside applications is susceptible to weathering and photo degradation, which often leads to surface discoloration, loss of brightness and surface deterioration. Research has shown that acetylated wood is more resistant against brown rot, white rot and soft rot, and more dimensionally stable than untreated wood. However, acetylated wood seems still to be disfigured by surface moulds ...
L Ross Gobakken, S Bardage, C J Long II
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
Using hyperspectral imaging to detect and quantify mould and blue stain on coated and uncoated wood
2014 - IRG/WP 14-10822
Hyperspectral imaging has been applied on the surface of samples of coated and uncoated Norway spruce (Picea abies) as a new technique to detect and quantify growth of mould and blue stain fungi. Principal Component Analysis of the hyperspectral images resulted in a clear visualization of the fungi and the amount of mould coverage could be estimated. This indicates that NIR hyperspectral imaging c...
L Ross Gobakken, I Burud, A Flø, K Kvaal, T K Thiis
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
Effects of UV Radiation on Melanization and Growth of Fungi Isolated from Weathered Wood Surfaces
2015 - IRG/WP 15-10842
This research tests the hypothesis that fungi isolated from weathered wood will respond to elevated levels of UV radiation by increasing their melanin production. To test this hypothesis, we measured the melanin production and mycelial color of Aureobasidium pullulans and Cladosporium cladosporioides, before and after the fungi were grown under artificial UV, visible light and complete darkness. T...
V A Hernández, P D Evans
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
Termiticide Residues in Building Foundation Aggregate Fills After Trench and Surface Applications
2015 - IRG/WP 15-30679
Termiticide concentrations (ppm) in aggregate fill were determined by measuring active ingredient (a.i.) residues of two pyrethroid termiticides, Up-Cyde Pro® 2EC-cypermethrin, and BaseLine® EC-bifenthrin, at 24.0 hours, and then at 6.0- and 12.0-months after ‘horizontal’ surface applications, perimeter ‘trenching and rodding’ applications, or ‘rodding only’ trench applications at lo...
B M Kard, C E Koneman, K T Shelton, C C Luper, R A Grantham
Simulation of surface climate and mould growth on wooden façades
2016 - IRG/WP 16-20585
The weathering of wooden surfaces is normally caused by mould growth, lignin deterioration and leaching of extractives. For well insulated buildings, the effect of the interior climate on the outer surface is small and sometimes negligible. This paper describes simple models for surface temperature and moisture conditions on a wooden façade that can further be used to model weather degradation an...
T K Thiis, I Burud, D Kraniotis, L Ross Gobakken
Formation of hydrophobic wood surface by means of thermal treatment and surface modification with alkyl ketene dimer (AKD)
2016 - IRG/WP 16-40738
One of the major shortcomings of wood-based materials compared to technical materials is attributed to their poor dimensional stability in changing climates and in contact with liquid water. Heat treatment induces chemical change with a consequent decreasing of reactivity of the material showing unwanted surface inactivation. Alkyl ketene dimer (AKD) is a widely used sizing agent in papermaking, w...
T Lovaglio, T Meints, L Todaro, W Gindl-Altmutter
The influence of log soaking temperature and thermal modification on the properties of birch veneers
2016 - IRG/WP 16-40749
In veneer manufacture the logs are routinely soaked in heated water baths in order to soften the wood prior to peeling. The temperature of the water may vary greatly between batches; however, the influence of log soaking temperature on veneer properties has had little research attention. Uncontrolled moisture is known to cause problems in wood-based materials, while thermal modification offers a m...
S Källbom, K Laine, M S Moghaddam, A Rohumaa, K Segerholm, M Wålinder
Evaluation of surface cracks on wood – physical assessment versus subjective sensation
2017 - IRG/WP 17-20617
In the presented studies from the University of Goettingen (Study I) and the University of Hannover (Study II), the assessment of cracks with different methods and their acceptance in general as well as depending on different target groups are investigated. The aim was to determine which factors are relevant for a crack evaluation and which visual impression of a wooden surface is tolerable for co...
A Gellerich, C Brischke, L Emmerich, L Meyer-Veltrup, P Kaudewitz
Bacterial adhesion to selected wood finishes
2017 - IRG/WP 17-40793
A new generation of furniture, including antibacterial surfaces, should adjust to the changing needs of an ageing population. Respectively, determination of bacterial adhesion on wooden surfaces, finished with various wood finishes or coating is an important topic. The main aims of our work were of a preliminary character. We wanted to state if the existing methods for testing of bacterial adhesio...
M Petrič, D Kekec, J Žigon, K Godič Torkar, K Bohinc
Surface Protection of Wood with Metal Acetylacetonates
2017 - IRG/WP 17-40802
Metal acetylacetonates are coordination complexes of metal ions and the acetylacetonate anion. They have diverse uses as catalysts, cross-linking and curing agents and adhesion promotors. Some metal acetylacetonates can photostabilise polymers whereas others are photocatalysts. We hypothesise that the ability of metal acetylacetonates to photostabilise wood will vary depending on the metal in the ...
Yuner Zhu, P D Evans
Aesthetic changes of coated thermally modified wood after artificial weathering
2017 - IRG/WP 17-40819
The thermal modification process affects the chemical configuration of the wood matrix improving some physical properties and durability. In addition, the distinctive dark tones of thermally modified timber increase the economic value of several light-coloured species. However, heat-treatment alters the substrates and it could influence in the application of coating products, necessaries to mainta...
R Herrera, J Sandak, E Robles, J Labidi
Wood Hydrophobic Modification by Mixed Wax Emulsions
2018 - IRG/WP 18-40839
An environmental-friendly, economical and facile method to construct hydrophobic system for improving wood repellency was applied in this study. Using paraffin wax and carnauba mixed wax O/W emulsions can simultaneously fabricate continuous wax films and rough structures in wood internal and external surface under appropriate heat treatment. In the study, single and mixed wax emulsions of 4% solid...
C Chen, W Wang
Visual appearance of unpainted wooden claddings during the first year of outdoor exposure: Evaluation of surface mould growth, lightness (L*) and wasp attack
2018 - IRG/WP 18-40841
This study addresses changes in visual appearance of unpainted wood materials exposed outdoors. Specimens of Norway spruce (Picea abies) Scots pine (Pinus sylvestris), aspen (Populus tremula), acetylated Radiata pine (Pinus radiata) and DMDHEU-modified Scots pine sapwood were exposed facing south in Ås, Norway for 60 weeks. During this period, surface mould growth development and wasp attack were...
S Karlsen Lie, L Ross Gobakken, G I Vestøl, O Høibø
Potential Use of the Pigment from Scytalidium cuboideum and Chlorociboria aeruginosa as an UV-light Protection Additive in Oil Finishes
2019 - IRG/WP 19-40868
UV-light degradation of wood is one of the top reasons for consumer replacement of outdoor wooden structures. This type of degradation is seldom mechanical, and is instead often motivated by loss of aesthetics (graying). There are numerous commercial products available on the market that deal with this loss of color, many of which contain added pigments to ‘rejuvenate’ or ‘revitalize’ grey...
S M Vega Gutierrez, D W Stone, R He3, P T Vega Gutierrez, Z M Walsh, S C Robinson