Your search resulted in 302 documents. Displaying 25 entries per page.
Assessment of Scots pine sapwood susceptibility to moulds by determination of fungi growth and ergosterol content in infested wood
2014 - IRG/WP 14-20540
The susceptibility of wood to filamentous fungi (mould) attack is determine mainly by laboratory methods with descriptive grading of fungal growth on the surface of the wood specimens. It is a lot of different grading scale of fungi growth, but determination of the size of fungi growth is many times not easy, not clear and often difficult. Although the filamentous fungi are not included to microor...
A Fojutowski, A Koziróg, A Kropacz
Scanning Transmission X-ray Microscopy as a tool for examining chemical changes in wood cell walls due to enzymatic activity
2014 - IRG/WP 14-20556
As development of techniques for examining enzymatic activity on solid, complex biological materials, is considered to be an important factor in further development of enzyme applications and for understanding the decay of plant materials, this study explores applicability of Scanning Transmission X-ray Microscope (STXM) for determining chemical changes in enzymatically treated samples at the cell...
D Jeremic, R Goacher, R Yan, C Karunakaran, E R Master
Resistance of fungal derived pigments to ultraviolet light exposure
2014 - IRG/WP 14-30642
The potential for using fungal derived pigments as surface treatments for limiting photodegradation of wood was investigated. Extracts from Chlorociboria aeruginosa and Scytalidium cuboideum were compared with a traditional aniline dye and chromic acid treatment. Hybrid poplar sapwood samples treated with these solutions were exposed to 86.4 kj/m2 of UV radiation and assessed for lignin degradatio...
H G Beck, S Freitas, G Weber, S C Robinson, J J Morrell
Thermal durability and biodegradation of tannin lignin adhesives
2014 - IRG/WP 14-40657
Mimosa tannins and lignosulfonates were used in wood adhesives formulation to substitute resins based on formaldehyde. Mimosa tannins were mixed with either glyoxalated sodium lignosulfonates or glyoxalated ammonium lignosulfonates. The ratios of mimosa tannins and sodium lignosulfonates varied from 20% tannins to 60% tannins. The thermal durability of the adhesives were analysed by thermogravimet...
L Chupin, B Charrier, A Pizzi, F Charrier
Modern Instrumental Methods to Investigate the Mechanism of Biological Decay in Wood Plastic Composites
2014 - IRG/WP 14-40674
Various instrumental techniques were used to study the fungal decay process in wood plastic composite (WPC) boards. Commercial boards exposed near Hilo, Hawaii (HI) for eight years in both sun and shadow locations were inspected and tested periodically. After eight years of exposure, both boards were evaluated using magnetic resonance imaging (MRI), while a selected area of the board exposed in sh...
G Sun, R Ibach, M Gnatowski, J Glaeser, M Leung, J Haight
Experiences with an industrial system for controlled thermal wood modification in pressurized unsaturated steam
2014 - IRG/WP 14-40678
Thermal wood modification in pressurized reactors has a long history, but these processes are to date industrially scarcely used, because of the relatively complicated process equipment, compared to the more common high-temperature processes in kilns at atmospheric pressure. However, based on our practical experience with the FirmoLin® process, supported by recent scientific findings, it is foun...
W Willems
Lignin Modification to Produce Sustainable Polyurethane Resin for Wood Coatings
2014 - IRG/WP 14-40682
The use of lignin as the most abundant aromatic natural polymer has been evaluated for use in the production of lignin-based polyurethane resin for coating applications. Coatings are made of resins (ca. 50%), which today are mainly derived from petroleum-based polymers. This study is focused on the development of an environmentally friendly method of modifying lignin to be used as source of natura...
M Nejad, M Arefmanesh, S Chandra, J Mostaghimi, E Master
Interpretation of moisture monitoring data - Relevance of moisture content thresholds for fungal decay
2015 - IRG/WP 15-10839
It is widely accepted that besides temperature wood moisture content (MC) is the key factor when it comes to durability of wooden structures exposed to weathering. Many approaches to predict the service life of wooden structures have therefore been based on using wood MC as one major input-variable to develop dose-response relationships between material climate and decay response. However, to impr...
L Meyer, C Brischke
Introduction of the COST FP 1303 Cooperative Performance Test
2015 - IRG/WP 15-20567
COST Action FP 1303 “Performance of bio-based building materials” successfully started in October 2013 and an ambitious program was set up for the four year programme. COST Actions provide an excellent opportunity for collaborative research, e.g. in the frame of Round Robin tests. The idea of this respective test was to distribute a fairly simple test set up to as many places in Europe as poss...
M Humar, C Brischke, L Meyer, B Lesar, N Thaler, D Jones, S Bardage, C Belloncle, J Van den Bulcke, J M Abascal, G Alfredsen, D Baisch, B Brunnhuber, G Cofta, E Grodås, E Frühwald Hansson, M Irle, H Kallakas, J Kers, M Klamer, P Larsson Brelid, A B Maider, K C Mahnert, E Melcher, R Möller, M Noël, L Nunes, G A Ormondroyd, S Palanti, N Pfabigan, A Pilgård, A O Rapp, P Schumacher, E Suttie, T Teppand, M Touza, J Van Acker
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
A novel enzymatic treatment as a new approach for wood protection
2015 - IRG/WP 15-40701
Wood durability is a worldwide concern and most treatments tend to fail with regard to their efficacy along the time. Weather conditions lead to a loss of the treatment substances into the surrounding environment and, in consequence, generate also a public health concern.
Recently, the employment of oxidative enzymes, such as laccases, has been proposed as a tool for lignocellulosics modificatio...
C Fernández-Costas, S Palanti, M Ángeles Sanromán, D Moldes
Fungal decay of archaeological waterlogged oak timber: role of the mineral content
2016 - IRG/WP 16-10873
In service, wood foundation poles are subjected to water level fluctuation in soil. While wood is saturated by water only bacterial decay occurs. When oxygen content increases and moisture content decreases, severe fungal attack may occur. To evaluate the long term fungal durability of wood foundation pole in the context of service, 300 years waterlogged archaeological wood poles were used. The oa...
A Besserer, M Letellier, E Fredon, Q Kleindienst, M-L Antoine, C Perrin, J Lallemand, C Rose, M-C Trouy
Weather degradation of thin wood samples
2016 - IRG/WP 16-20578
Untreated wooden surfaces degrade when exposed to varying doses of natural weathering. In this study, thin wood samples were studied for weathering effects with the aim of modeling the degradation utilizing Near-infrared hyperspectral imaging. Several sets of samples were exposed outdoors for time intervals from 0 to 21 days, and one set of samples was exposed to UV-radiation in a laboratory chamb...
I Burud, K A Smeland, K Hovde Liland, T K Thiis, J Sandak, A Sandak, L Ross Gobakken
Variation in moisture content in field trials according to use class 3.2 conditions
2016 - IRG/WP 16-20580
Different test methods to determine the durability of wood in use class 3 (EN 335:2013) are available. Fungal degradation of wood requires liquid water. Different Standards (EN 335-1:2006; DIN 68 800:2011) specify the risk for decay with moisture content (mc) of above 20%. EN 335 (2013) does not specify moisture content but rather defined limited wetting conditions (use class 3.1) or prolonged wet...
S Bollmus, A Gellerich, H Militz
Superhydrophobic treatment of Norway spruce wood for improvement of its resistance against brown rot and moulds
2016 - IRG/WP 16-40734
Water repellence of wood can be increased and its some other properties influenced by introduction of hydrophobic chemicals into and on cell walls without affecting the wood’s bulk density due to lumen filling. Herein, a simple dipping method to insert octadecyltrichlorosilane (OTS) into cell walls and to deposit the self-assembled hydrophobic monolayers (SAMs) of OTS is reported. It was found o...
A Kumar, P Ryparová, P Hajek, B Kričej, M Pavlič, A S Škapin, M Šernek, J Tywoniak, J Žigon, M Petrič
Role of cell wall specific moisture content on the brown-rot fungal attack on wood
2016 - IRG/WP 16-40736
Wood is a hydroscopic resource because the cell wall polymers contain hydroxyl and other oxygen-containing groups that attract moisture through hydrogen bonding. Moisture content varies with changing moisture content in its environment. The moisture content in wood is responsible for many of the performance properties we observe. The strength properties of wood are dependent on the moisture con...
R M Rowell
New perspectives for wood protection: enzyme-based treatments
2016 - IRG/WP 16-40742
Wood protection research is continuously looking for more benign and effective treatments. One of the main concerns deals with the toxicity of the active compounds employed in the formulations of the preservatives, since they could become a health and environmental issue. Secondly, long-lasting treatments are preferred in order to increase the service life of the treated wood. Weathering condition...
C Fernández-Costas, S Palanti, M Á Sanromán, D Moldes
Lignin-Based Adhesive for Engineered Wood Products
2016 - IRG/WP 16-50319
Lignin as a naturally occurring polyphenolic compound has an excellent potential to replace petroleum-based phenol in formulation of phenol-formaldehyde adhesive that are used in manufacturing of engineered wood products. However, there are three major obstacles in application of polymeric lignin as phenol replacement: 1) low reactivity toward phenol, 2) high molecular weight, and 3) high polydisp...
I Kalami, M Arefmanesh, E Master, M Nejad
Contamination of recycled wood from selected recycling companies in Europe
2016 - IRG/WP 16-50322
Recycled wood is becoming more and more important material source for production of new materials and chemicals. For good quality of end products predominately clean recycled wood should be used. In present research, we have focus on concentrations of non-wooden materials in recycled wood and presence of inorganic pollutants: chlorine (Cl), chromium (Cr), copper (Cu), zinc (Zn), lead (Pb), iron (F...
B Lesar, M Humar, G Hora
Case study: “Riesenbühlturm”
2017 - IRG/WP 17-20599
In this case study four 7 m long Douglas fir crossbeams were investigated regarding the remaining metal and moisture content. The crossbeams were replaced from a timber tower after 10 years of service in the Black Forest region (South Germany) due to fungal decay. From each of the crossbeams five stem discs were taken and relevant parameters (density, moisture and remaining metal content) were de...
E Melcher, J Müller
The sorption behaviour of wood
2017 - IRG/WP 17-20605
The use of dynamic vapour sorption to determine the sorption properties of wood has become an increasingly popular technique. The method has many advantages when compared with many other gravimetric methods. However, it is necessary to set an equilibrium condition in order to obtain data for an isotherm in a reasonable amount of time. An important recent finding has been that multiple sorption cyc...
C Hill
Modelling of moisture content in timber bridge details
2017 - IRG/WP 17-20613
The design of details is an important aspect in durability design of timber bridges. Details are often considered the weakest points in bridges due to their tendency to trap and accumulate moisture and thus facilitate decay. When designing maintenance plans and inspection intervals, it is important to know how design choices will come to influence the service life. Moreover, service life and wood ...
J Niklewski, C Brischke, E Frühwald Hansson, L Meyer-Veltrup
COST FP 1303 Cooperative Performance Test – Results after two years outdoor exposure
2017 - IRG/WP 17-20620
COST Action FP 1303 ‘Performance of Bio-Based Building Materials’ started in October 2013 and an ambitious program was set up for four years. Among this a collaborative field test was planned. The idea of the cooperative performance test was to distribute a fairly simple test set up to as many places in Europe as possible in order to collect performance data reflecting the full range of climat...
B Lesar, M Humar, C Brischke, L Meyer-Veltrup, D Jones, N Thaler, J M Abascal, G Alfredsen, B Brunnhuber, E Grodås, M Irle, J Kers, M Klamer, K-C Mahnert, E Melcher, S Palanti, M Noël, E Suttie, N Pfabigan, M Touza
Moisture performance of wood determined in laboratory and field trials
2017 - IRG/WP 17-20621
It is widely accepted that wood moisture content (MC) is the key factor when it comes to durability of wooden structures exposed to weathering. The moisture performance of wood and wood-based products has been recognized as key element in wood durability and wood protection. Actually, it should be considered as major component of the material-intrinsic resistance of wood, but never found its way i...
D Kržišnik, N Thaler, B Lesar, M Humar
Moisture content as a quality control parameter in thermally modified timber production
2017 - IRG/WP 17-20622
Quality assurance (QA) or factory production control (FPC) is necessary to ensure a proper production process. The requirements of QA/FPC can result from EN and national standards, quality assurance systems, or producer-specific rules.
TMT producers must ensure that the process was correct, and to ensure traceability of products. In addition to the electronic records, the material should be che...
W Scheiding, H Turkulin, S Stein