Your search resulted in 481 documents. Displaying 25 entries per page.
Postia placenta gene expression during growth in furfurylated wood
2010 - IRG/WP 10-10734
Modified wood can provide protection against a range of wood deteriorating organisms. But we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward for the mode of action against wood decaying fungi, including inhibition of action of specific enzymes, but they still need further testing. In this study gene expression of the b...
G Alfredsen, C G Fossdal
Glutathione transferases as functional biomarkers of wood degradation?
2010 - IRG/WP 10-10735
The recent release of several fungal genome sequences allows the report of an overview of fungal glutathione transferases (GSTs) focused on their function in the wood-degrading basidiomycete Phanerochaete chrysosporium. A genomic and phylogenetic analysis of GST classes in various sequenced fungi –zygomycetes, ascomycetes and basidiomycetes- revealed some specificity in GSTs distribution, in com...
E Gelhaye, M Morel
Natural durability of African Padauk and Niove. Comparison of new trials and former data from the CIRAD database
2010 - IRG/WP 10-10743
African Padauk (Pterocarpus soyauxii) and Niove (Staudia kamerunensis) were tested in laboratory against Basidiomycetes. The results were calculated according to the requirements of EN 350-1 (1994) and XP CEN/TS 15083-1 (2006). Padauk samples showed a high durability and very small variations between trees and within tree. Niove presented a high durability, but with notable differences according ...
Y N N’Kolo Meze’e, N Leménager, C Baudassé, M-F Thévenon
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Simulation and Investigation of Wood Degradation by Erosion Bacteria in Laboratory Experiments
2010 - IRG/WP 10-20431
A Microcosm experiment was successfully set up to establish, monitor and manipulate bacterial wood degradation under low oxygen conditions. Sound pine sticks were placed in waterlogged sediment from a heavily decayed pine pile foundation site in Amsterdam. The system was subject to different gassing treatment regimes in order to investigate the role of oxygen in the bacterial degradation process o...
J Gelbrich, E I Kretschmar, N Lamersdorf, H Militz
The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz
Detection of Wood Destroying Fungi Using DNA Microarray Technology
2010 - IRG/WP 10-20435
Wood decay fungi of the phylum Basidiomycota cause serious damage to wooden constructions and building elements. The elimination and the appraisement of fungal decay require an assured species identification. Conventional fungal diagnostics are mainly based on morphological characteristics by macro- and microscopy analysis. For some years, standardised and highly sensitive molecular methods focuss...
K Jacobs, N Rangno, W Scheiding, B Weiss, D Müller, C Hiller, W Brabetz
Profiling fungal community in wood decay ecosystem by Denaturing High-Performance Liquid Chromatography
2010 - IRG/WP 10-20443
A DNA-based fingerprinting technique, Denaturing High Performance Liquid Chromatography (DHPLC) was developed to profile fungal communities colonizing indoor timber. Molecular fungal diversity was assessed using amplification based on the Internal Transcribed Spacer (ITS1) rDNA of 74 wood samples collected from infected buildings in France. Due to its high sensitivity, the PCR-DHPLC technique was ...
S Maurice, G Le Floch, M Le Bras-Quéré, J P Rioult, G Barbier
Effects of polyvinyl alcohol on leachability and efficacy of boron wood preservatives against fungal decay and termites attack
2010 - IRG/WP 10-30526
In this study, the use of polyvinyl alcohol (PVA) as boron fixative agent was investigated. Two levels of PVA (2.5 and 4%) were evaluated with disodium octaborate tetrahydrate (DOT) at three concentrations (1, 2 and 4% boric acid equivalent (BAE) using a double vacuum impregnation processes on Scots pine sapwood specimens. Leaching was performed according to a laboratory leaching procedure. Boron ...
A Mohareb, M F Thévenon, E Wozniak, P Gérardin
Degradation of Carbon-Based Preservatives by Black-stain Fungi
2010 - IRG/WP 10-30533
Some black-stain fungi are known to exhibit resistance to carbon-based preservatives. However, the cause of this resistance is unclear. The fungi may have mechanisms to tolerate these chemicals, or they may be able to degrade and detoxify them. Fungi capable of degrading carbon-based preservatives are of interest for possible bioremediation of carbon-based preservative-treated wood at the end of i...
R Stirling, P I Morris
Laboratory evaluation of borate amine: Copper derivatives in wood for fungal decay
2010 - IRG/WP 10-30543
The aims of this study were to evaluate borate: amine: copper derivatives in wood for fungal decay protection as well as the permanence of copper and boron in wood. Wood treated with each of four derivatives of borate:amine:copper prevented fungal decay. Disodium tetraborate ecahydrate (Borax):amine:copper derivatives with retentions of 0.61 to 0.63% after water leaching prevented decay by Gloeo...
G Chen
Preventing decay in termite monitoring stations
2010 - IRG/WP 10-30546
In-ground monitoring stations and termite baits are widely used in the southern United States with the intent of detecting and eradicating subterranean termite activity near buildings. These stations comprise a wood (or other cellulose material) substrate (monitor) and perhaps a termiticidal toxicant (bait) held in a plastic cage that allows for both easy examination and access by termites. The us...
A M Taylor, Jae-Woo Kim, S Duarte, L Nunes, J D Lloyd
Fungal decay resistance and mechanical properties of plywood panels made from maritime pine (Pinus pinaster) and bonded with cornstarch-quebracho tannin-phenol formaldehyde adhesive
2010 - IRG/WP 10-40490
The aim of this work is to demonstrate the performances of cornstarch-quebracho tannin-based resins designed as adhesive in the plywood production. In this way, the cornstarch and quebracho tannin was introduced in the classic adhesive formulation in order to supply a part of phenol-formaldehyde (PF). In order to evaluate the mechanical performances of optimal cornstarch-quebracho tannin-PF, plywo...
F Charrier, A Moubarik, A Allal, A Pizzi, B Charrier
Moisture dynamics of WPC as basis for biological durability
2010 - IRG/WP 10-40520
The largest market for wood-polymer composites (WPCs) is currently decking. Although many products are commercially available, a proper standard for the assessment of the biological durability of WPC does not exist. Recommended standards for testing resistance against basidiomycetes should be completed with a method to bring the specimens in a worst case situation, obtaining a moisture level high ...
N Defoirdt, J Van Acker, J Van den Bulcke
Biological degradation of acetylated wood after 18 years in ground contact and 10 years in marine water
2010 - IRG/WP 10-40522
This paper addresses the resistance to biological degradation of acetylated wood.
Firstly, it presents results from an EN 252 test after 18 years’ exposure. The test is still running in Nordic NWPC test fields, Simlångsdalen in Sweden and Viikki in Finland. Results from this test were presented after 5 years’ exposure ( IRG/WP 97-30139), and showed that the resistance of acetylated wood wit...
P Larsson Brelid, M Westin
Fungal biodegradation of CCA-treated wood wastes
2011 - IRG/WP 10-50276
Fungal biodegradation could be employed as a pretreatment method to alleviate problems caused by landfill disposal of CCA-treated wood wastes (e.g. a shortage of landfill space and a release of leacheate). It could be used to decrease the volume of waste and to remove metals from waste simultaneously. We have screened hundreds of decay fungi, including fungi isolated from CCA-treated wood in servi...
Gyu-Hyeok Kim, Yong-Seok Choi, Jae-Jin Kim
Basidiomycete colonization of Scots pine sapwood quantified by qPCR and TGA
2011 - IRG/WP 11-10750
Scots pine (Pinus sylvestris L.) is an important softwood species in Northern Europe and is frequently used as material for various wood protection systems. In Europe, EN 113 is the standard basidiomycete laboratory durability test method, using mass loss as evaluation criteria. In this paper quantitative real-time PCR (qPCR) and thermogravimetric analysis (TGA) was used to characterize coloniza...
G Alfredsen, S Bollmus, T K Bader, K Hofstetter
Measuring fungal cellulolytic enzyme activity in degrading wood
2011 - IRG/WP 11-10753
An enzyme assay which measures enzyme activity directly from wood will assist in the fundamental understanding of the enzyme components of the decay mechanism of rot fungi and any changes in the presence of wood protectants. At present, to measure fungal carbohydrate degrading enzyme activity in the presence of wood, two methods are used: either 1) the enzyme is measured in the growth media contai...
S M Duncan, J S Schilling
Molecular investigation of Postia placenta growing in modified wood
2011 - IRG/WP 11-10756
Brown rot is the most common and destructive type of fungal decay for wood in service. These fungi depolymerize preferentially the structural carbohydrates, cellulose and hemicellulose in the cell wall leaving oxidized lignin behind. Modified wood can provide protection against a variety of wood deteriorating organisms, including decay fungi. However, there is still little known about the mode of ...
B Schmöllerl, G Alfredsen, C G Fossdal, M Westin, A Steitz
Growth conditions for fungal decay in wooden constructions – practical experience versus literature
2011 - IRG/WP 11-10758
Data regarding moisture and temperature requirements of decay fungi found in literature have been compared to experience from observations in a large number of Norwegian buildings. A number of selected situations are discussed, among those exposure to high relative humidity, exposure to free water and decay in the supposedly adverse conditions on Svalbard. The moisture content in wood has to be at...
M Sand Sivertsen, J Mattsson
The influence of moisture content and wood pH variation on fungal melanin formation in wood substrates
2011 - IRG/WP 11-10759
Wood decay patterns are strongly influenced by the conditions of the wood substrate, including moisture content and pH. In an antagonistic environment some fungi respond with pigment formation that helps to isolate and protect their mycelium. This is often associated with slower fungal growth and delay of wood mass loss. Dark colored melanin is the most common pigment formed by wood decay fungi, a...
D Tudor, S C Robinson, P A Cooper
Durability testing of coconut shell according to ENV 807
2011 - IRG/WP 11-10761
Coconut shell was tested in the laboratory according to the European standard ENV 807 with three different soil types: compost soil, brown rot/soft rot rich soil and white rot/soft rot rich soil. Mass losses between 14 and 16 % were achieved with all three soils, indicating that the decay type is of little importance in the degradation process. Somewhat higher mass losses, 19-22 % were obtained fo...
J Jermer, A H H Wong, K Segerholm, T Nilsson
A comparative study and evaluation of methodologies used for determining wood preservative penetration
2011 - IRG/WP 11-20475
A series of methods for determining penetration of wood preservatives into the wood structure have been developed for either quality control (QC) or research and development purposes. QC methods range from monitoring the solution uptake, applying colour indicators or sampling specific wood samples followed by wood acid digestion/atomic absorption spectroscopy (AAS) or solvent extraction/chromatogr...
R Craciun, R Moeller, J Wittenzellner, T Jakob, J Habicht
Utilization of thermodesorption coupled to GC-MS to study kinetics of thermodegradation of different wood species
2011 - IRG/WP 11-40559
Thermdesorption coupled to Gas Chromatography coupled to Mass Spectroscopy (TD-GC-MS) has been investigated to identify volatile degradation products generated during wood heat treatment by mild pyrolysis. For this purpose, wood samples of different softwood and hardwood species have been heat treated under nitrogen for different temperatures comprised between 180 and 230°C during 15 min. in the ...
K Candelier, M Chaouch, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
In-situ experimental treatment and consolidation of degraded timber elements from a XIX century building
2012 - IRG/WP 12-10767
This paper presents the in situ experimental conservation work performed on three timber structural elements from a XIX century building: two floor beams and one roof beam. The palace was built in 1877 in the centre of Lisbon initially with residential purposes. It has four floors, with timber structural horizontal elements, stairs and roof beams (generally of Pinus sylvestris L.). The exterior wa...
D F Henriques, J de Brito, L Nunes