Your search resulted in 1400 documents. Displaying 25 entries per page.
Resistance of pine and spruce heartwood against decay - The effect of wood chemical composition and coating with water-borne wood oil product
2006 - IRG/WP 06-10597
Natural durability of wood has been widely studied, but the combination of the natural durability and different treatments has not been the focus of many studies. The durability of wooden products is mainly based on the water permeability and the resistance against organisms. In this study, the water absorption and decay resistance of sapwood and heartwood of Scots pine and Norway spruce were exam...
H Viitanen, S Metsä-Kortelainen, T Laakso
High-energy multiple impact (HEMI)-test – Part 2: A mechanical test for the detection of fungal decay
2006 - IRG/WP 06-20339
The suitability of the high-energy multiple impact (HEMI)-test for detection of early fungal decay was examined. The HEMI – test characterizes the treatment quality of thermally modified wood by stressing the treated material by thousands of impacts of pounding steel balls. This method differentiates between heat treatment intensities, which are expressed by structural changes of the wood. Simil...
C R Welzbacher, C Brischke, A O Rapp
Chelator-Mediated Fenton Chemistry in Wood Degraded by Fungi
2007 - IRG/WP 07-10618
Wood specimens were colonized by individual isolates of brown rot, white rot, soft rot and blue (sap) stain fungi. Ethyl acetate extracts of the ground wood were analyzed for their iron-reducing capabilities using a ferrozine-based assay. Extracts from wood colonized by brown rot fungi showed a significantly greater iron-reducing capability than extracts from wood colonized by white rot fungi or n...
B Goodell, G Daniel, J Jellison, Yuhui Qian
Decay Resistance Properties of Hemicellulose-Extracted Oriented Strand Board
2008 - IRG/WP 08-10644
There is increasing interest in using cellulosic biomass as the basis for a renewable source of energy. Although the traditional focus has been on cellulose, researchers are also exploring the possibility of using hemicelluloses because they can be removed with hot water leaving the wood product intact for other applications. However, there is concern that removing hemicelluloses from the precur...
C Howell, J Paredes, S Shaler, J Jellison
Feasibility study on three furfurylated non-durable tropical wood species evaluated for resistance to brown, white and soft rot fungi
2008 - IRG/WP 08-40395
Furfurylation can protect non-durable wood species against biological degradation, but the method used today cannot fully protect the heartwood of Scots pine due to insufficient penetration. In order to test alternative wood substrates for furfurylation, three Malaysian grown wood species (Kelempayan, Rubberwood and Sena) were furfurylated and subjected to soil block decay testing. Their performan...
T Mark Venås, A H H Wong
Impact of decay and blue stain causing fungi on the structural integrity of wood
2009 - IRG/WP 09-10699
The potential influence of diverse decay patterns caused by different brown rot provoking basidiomycetes on the structural integrity of wood was investigated. Additionally the potential impact of blue stain on the structural integrity was examined. Therefore decayed Norway spruce (Picea abies Karst.) specimens representing a wide range of mass loss, caused by four different brown-rot fungi and one...
C Brischke, C Welzbacher, T Huckfeldt, F Schuh
Degradation of wood veneers by Fenton’s reagents: effects of low molecular weight phenolic compounds on hydrogen peroxide decay and tensile strength loss
2009 - IRG/WP 09-20400
Pine wood (Pinus sylvestris) veneers strips were incubated in acetate buffer containing hydrogen peroxide and iron to mimic mechanisms of brown rot decay and assess the degradation of cellulose through analysis of the tensile properties of the decayed wood. The tensile properties of thin wood strips treated with Fenton system reagents or precursors were determined and correlated to weight loss as ...
Yanjun Xie, R Well, Zefang Xiao, B Goodell, J Jellison, H Militz, C Mai
Micronized Copper Preservative Systems: Observations on the Release of Cupric ion (Cu2+) from Treated Wood and Performance against Wood Decay Fungi
2009 - IRG/WP 09-30519
In an attempt to address the mechanism of action of micronized copper preservatives, a 20-week continuous water leaching study was conducted. The leaching results indicated that, once impregnated in wood, micronized copper preservatives continuously release cupric ion, and the levels of cupric ion released from micronized copper treated wood are higher than those released from CCA treated wood, a...
J Zhang, R Ziobro
Protection mechanisms of modified wood against decay by white and brown rot fungi
2010 - IRG/WP 10-10713
The resistance of beech and pine wood blocks treated with 1,3-dimethylol-4,5-dihydroxyethylene urea (DMDHEU) against T. versicolor and C. puteana increased with increasing WPG. Full protection (mass loss below 3%) was reached at WPGs of approximately 15% (beech) and 10% (pine). Metabolic activity of the fungi in the wood blocks was assessed as heat or energy production determined by isothermal mic...
C Mai, P Verma, Yanjun Xie, J Dyckmans, H Militz
Fungal Attack on Lignin and Cellulose: Elucidation of Brown- and White-Rot Mechanisms Comparing Biomimetic and In-Vivo Degradation Patterns
2010 - IRG/WP 10-10714
This paper examines research and hypotheses that have been developed over several years on wood degradation mechanisms. This information is combined with new data and analyses to explain why wood decay patterns caused by brown-rot fungi and specific types of white-rot fungi are different. New data, including work with both biomimetic studies on low molecular weight compounds, degradative enzymes, ...
V Arantes, B Goodell, A M F Milagres, Yuhui Qian, T Filley, J Jellison, S Kelley
A genomic sequencing approach to study wood decay and copper tolerance in the brown rot fungus, Antrodia radiculosa
2010 - IRG/WP 10-10720
We used Illumina paired-end short read sequencing (76 nt, 300 bp insert size) to produce a de novo assembly of the genome of Antrodia radiculosa, a copper-tolerant brown rot fungus that is capable of aggressive wood decay. Quality analysis of the base calls in the dataset (8.95 Gb) showed that the majority of the nucleotide sequence was of the highest quality with 5% in the lowest quality group. ...
J D Tang, T Sonstegard, S Burgess, S V Diehl
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
Testing of decay resistance of sapwood and heartwood of thermally modified Scots pine and Norway spruce
2010 - IRG/WP 10-40523
Thermal modification at elevated temperatures changes the chemical, biological and physical properties of wood. One of the main targets of thermal modification is to increase the biological durability and decay resistance of wood. Although the effects of thermal modification on wood have been widely studied, the significance of sapwood and heartwood on the resistance of thermally modified wood has...
H Viitanen, S Metsä-Kortelainen
Gene expression analysis of a copper-tolerant brown rot fungus on MCQ-treated wood
2011 - IRG/WP 11-10748
Most brown rot fungi are copper-tolerant, which makes them difficult to control with copper-based wood preservatives like MCQ. To better understand what biological processes are regulated, we used our model species, Antrodia radiculosa, to examine expression of genes on MCQ-treated wood. Our hypothesis was genes that decreased copper bioavailability would be up-regulated early, when wood showed ...
J D Tang, A Perkins, S V Diehl
Decay resistance attributes of teak (Tectona grandis L. f.) wood: comparison of the fungicidal activities of quinones
2011 - IRG/WP 11-10752
The implication of quinones in decay resistance of teak wood is controversial. To better understand the role of individual quinone in this property, we studied the correlations between this latter and the content of 2-(hydroxymethyl)anthraquinone, tectoquinone, anthraquinone-2-carboxylic acid, 1,4-naphthoquinone, lapachol and the new compound 4’,5’-dihydroxy-epiisocatalponol found in teak wood...
F B Niamké, N Amusant, N Lemenager, G Chaix, M-F Thévenon, C Baudassé, S Kati-Coulibaly, A Amissa Adima, I Gossan Ado, C Jay-Allemand
Study of the durability of the Maderon® against wood decay fungi and insects
2011 - IRG/WP 11-40548
Many industries produce residues that are not easily degradable. One of these is nut husks which, due to their high level of resistance to biological and environmental degradation, have become an ecological problem. Maderón® is a material invented and patented in Spain employed as an ecological substitute and a modern alternative to certain uses of wood. At present, Maderón® is commercialized ...
M T Troya, F Llinares, P Jiménez, J I Fernández-Golfín, M Conde, R Díaz
Influence of soil moisture, Sarawak soil types and decay types on decay susceptibility of rubberwood and kelempayan
2012 - IRG/WP 12-10780
Wood and soils are important natural resources of the land, the former widely used as structural supports in contact with the latter. Many low durability wood species exposed to soil contact has reportedly high incidence of decay failures in poorly treated and untreated materials depending on soil types, properties and soil microbial virulence. This paper probes the relationship of the main soil t...
A H.H. Wong, P K.F. Chong, J Sabang
In-ground variability of decay intensity within a test field
2012 - IRG/WP 12-20496
Timber exposed in the ground faces most severe conditions in terms of exposure to wetting and fungal decay in the terrestrial environment, therefore wood durability tests are often conducted in test fields preferably ensuring the occurrence of all relevant decay organisms. One can also expect differences in decay within an individual field-test site due to localized distribution of certain organis...
C Brischke, S Olberding, L Meyer, T Bornemann, C R Welzbacher
Determination of the natural durability of solid wood against wood-destroying fungi - a European round-robin test
2013 - IRG/WP 13-20511
In Europe the durability of wood against wood-destroying basidiomycetes is tested according to CEN/TS 15083-1 (2005). Hitherto existing experience with this standard is quite heterogeneous and results from previous round-robin tests have stayed unreported or have been reported incompletely. In particular the need for natural pre-weathering of the test specimens to allow potential detoxification of...
C Brischke, C R Welzbacher, A Gellerich, S Bollmus, M Humar, K Plaschkies, W Scheiding, G Alfredsen, J Van Acker, I De Windt
Predicting the Rate of Decay, and the Potential for Misinterpretation of Proper Scientific Method
2013 - IRG/WP 13-20525
Predicting the rate of fungal attack in wood-based materials and its effect on properties remains the holy grail of wood products pathologists; however, achieving this goal is difficult because of the many variables associated with the process. This paper reviews some of the more important aspects of the decay process in relation to test methodology and then discusses how data are sometimes used b...
B S Goodell, J J Morrell
The activity of a wood-decaying fungus during drying and rewetting cycles measured by isothermal calorimetry
2013 - IRG/WP 13-20526
Wood decaying fungi are an essential part of any ecosystems as they are the main decomposers of cellulose and lignin-containing materials. But as wood is a common building material the risk for decay fungi growth and subsequent degradation of our construction material is a concern. There are important physiological aspects of the growth and activity of decay fungi that are unknown today, and witho...
S Johansson, L Wadsö, A Pilgård, G Alfredsen
Postia placenta cellulase gene expression in modified wood during incipient decay
2013 - IRG/WP 13-40626
In optimization of modified wood, it is important to understand the mode of action of the wood modification and how the fungi response to it. The aim of this study was to investigate the expression of cellulases during the first two weeks of Postia placenta exposure in acetylated, DMDHEU-treated and thermally modified as well as in untreated wood. Using real-time PCR, the gene expression patterns ...
R Ringman, A Pilgård, K Richter
The effects of copper proximity on oxalate production in Fibroporia radiculosa
2014 - IRG/WP 14-10823
Copper remains a key component used in wood preservatives available today. However, the observed tolerance of several critical wood rotting organisms continues to be problematic. Tolerance to copper has been linked to the production and accumulation of oxalate, which precipitates copper into insoluble copper-oxalate crystals, thus inactivating copper ions. The purpose of this study was to assess d...
K M Jenkins, C A Clausen, F Green III
Protein extraction from wood decay fungus Postia placenta
2014 - IRG/WP 14-10827
Wood decay fungi (often distinguished as white rot and brown rot) belonging to the basidiomycetes, are common inhabitants of forest litter, where they play an important role in carbon cycling. Brown rot fungi are perhaps the most important organism involved in the degradation of wood products, and of considerable economic importance. Brown rotted wood loses strength very early because of the rapid...
A Pilgård, P Arnold, K Richter
Decay resistance of wood-plastic composites reinforced with extracted or delignified wood flour
2014 - IRG/WP 14-40655
The moisture and decay resistance of wood-plastic composites (WPCs) reinforced with extracted or delignified wood flour (WF) was investigated. Three different extractions were preformed: toluene/ethanol (TE), acetone/water (AW), and hot water (HW). Delignification (DL) was performed using a sodium chlorite/acetic acid solution. All WPCs specimens were made with 50% by weight HDPE and WF, first com...
R E Ibach, Yao Chen, N M Stark, M A Tshabalala, Yongming Fan, Jianmin Gao