Your search resulted in 228 documents. Displaying 25 entries per page.
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
Quantitative and qualitative losses in wood of oriental spruce, Picea orientalis (L.) Link., induced by insects from forest to utility
2008 - IRG/WP 08-10647
In this study, some quantitative and qualitative losses in wood of oriental spruce, Picea orientalis (L.) Link., induced by insects from forest to utility were evaluated. In experimental plots, volume of trees damaged by Dendroctonus micans (Kug.) was 34% of the volume of total standing spruce trees in the oriental spruce forests of Turkey. The volume of standing trees that D. micans damaged was ...
H A Akinci, M Eroglu, G E Özcan, Ü C Yildiz
Inducing and Stimulating Spalting in Sugar Maple
2008 - IRG/WP 08-10652
Spalted wood has gained popularity in recent years as consumer preference has shifted towards unique and custom products. The process by which spalting is induced in clear lumber has evolved over time, and now involves much more than beer drinking and outdoor burial. Our work on the process of reliably producing spalted wood began in 2004 and involved testing a wide variety of white rot fungi on...
S C Robinson, D L Richter, P E Laks
A step towards a better understanding of fungal colonization of modified wood - QRT-PCR studies
2008 - IRG/WP 08-10653
The area of wood protection is in a period of change. New wood protection systems have been developed while their mode of action remains insufficiently understood. The development of molecular methods provides potential tools to investigate the interaction between modified wood and decay fungi. One small step to tackle some of the unsolved questions about the mode of action of modified wood is tak...
G Alfredsen, A Pilgård, A Hietala
Natural durability of different wood species in above ground applications - Weight and MOE loss
2008 - IRG/WP 08-10667
In Norway, exterior wood structures have traditionally, nearly exclusively been made of untreated Norway spruce (Picea abies (L.) Karst) and pressure treated Scots pine (Pinus sylvestris L.). In recent years there has been a tendency that other wood species, like various Norwegian hardwoods or imported species, have been used in exterior above ground applications, often not surface treated. For se...
F G Evans, P-O Flæte, G Alfredsen
A comparison of rates of decay and loss in stiffness of radiata pine and Douglas fir framing lumber
2008 - IRG/WP 08-20378
Stiffness loss with time was recorded for untreated radiata pine and Douglas fir framing size lumber and preservative treated radiata pine which dad been pre-inoculated with Oligoporus placenta, a brown rot decay fungus isolated from decaying untreated radiata pine framing. Between stiffness measurements, samples were contained in a plastic tank located outside at ambient temperature. Index of Con...
M Hedley, D Page, J van der Waals
Mechanical strength of wood from the Vasa shipwreck
2008 - IRG/WP 08-20381
Samples from three ancient ship wrecks (Vasa, Elefanten, and Gröne Jägaren) and recent oak samples as reference were examined with regard to mechanical strength using the high-energy multiple impact (HEMI) - test method, which delivers the resistance to impact milling (RIM) of a material. Adoption and optimisation of the test method for the particular sample size of the wooden drilling cores was...
A O Rapp, C Brischke, C R Welzbacher, T Nilsson, C Björdal
Treatment of Selected Lesser Used Timber Species against Subterranean Termites using Heartwood Extracts from Teak (Tectona grandis) and Dahoma (Piptadeniastrum africanum)
2008 - IRG/WP 08-30476
Lesser used timber species represent a valuable material for all-purpose uses. However, most of them are not durable. They are, for effective utilization, often treated with all manner of toxic synthetic substances to enhance their natural durability, especially in the tropics where conditions favour their deterioration. Most of these toxic synthetic substances often pose a threat to the environme...
A Asamoah, C Antwi-Boasiako, K Frimpong-Mensah
High Temperature Treated Wood
2008 - IRG/WP 08-40429
High temperature can modify internal structure and physic-chemical properties of wood by a controlled pyrolysis process. Such treatment, among other changes in properties, modifies the wood color in a way that resembles exotic species, increasing its market value. The main objective of this work is to determine the changes in wood properties caused by the effect of temperature and time, in order t...
C C Borges, A L Barbosa, R Faber de Campos, S T Targas
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
Accelerated weathering of nine tropical wood species from Cameroon
2009 - IRG/WP 09-10705
The natural durability of tropical species for building components has been a subject of recent concern and questioning, mainly the resistance to weathering. Weathering resistance of nine tropical species from Cameroon, namely Azobe, Bilinga, Bubinga, Teak, Dousie, Moabi, Musanga, Sipo and Padauk were evaluated using an accelerated weatherometer for 2016 hours. Measurement of moisture fluctuation,...
S Pankras, Jinzhen Cao, D P Kamdem
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
Durability and fungal colonisation patterns in wood samples after six years in soil contact evaluated with qPCR, microscopy, TGA, chitin- and ergosterol assays
2009 - IRG/WP 09-20402
There is a need to establish new objective and sensitive methods for early detection and quantification of decay fungi in wood materials. Molecular methods have proven to be a useful tool within wood protection issues, however, this field is still poorly explored and so far relatively few have used these methods within the field of wood deterioration. Among the techniques used in the indirect quan...
A Pilgård, G Alfredsen, I Børja, C Björdal
Termite Resistant Properties of Wood and Natural Fiber Plastic Composites - AWPA E1 Test Data
2009 - IRG/WP 09-40466
This paper deals with resistance properties of wood plastic composites against Formosan Subterranean Termites (FSTs) based on the AWPA E1 test standard. Sixteen laboratory WPC formulations, four WPC commercial materials, and southern pine (Pinus sp.) wood control were tested for termite mortality, sample weight loss, and sample damage rating. The results show that FSTs did attack WPC products in ...
Q Wu, T Shupe, J Curole, K Ragon, M Voitier, M Freeman, D Ring
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
Determination of a fixation time of wood preservatives: A discussion paper
2010 - IRG/WP 10-20436
The intention of that paper is to initiate a discussion on the basis of a French method in combination with a German approach regarding the need of a method for the determination of a fixation time and especially to obtain input as well as ideas concerning a possible test design. Since no harmonised European approach exists up to now concerning the determination of a fixation time, CEN TC 38 (2009...
E Raphalen, E Melcher
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
Photostabilization of Wood with Higher Molecular Weight UV Absorbers
2010 - IRG/WP 10-30524
Higher molecular weight UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. FTIR-spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzop...
P D Evans, M J Chowdhury
Preliminary Observations of the Photostabilization of Wood Surfaces with Cerium Oxide Nanoparticles
2010 - IRG/WP 10-40504
Reactive transition metal compounds, wood modification and grafting of UV absorbers have all been used to photostabilize wood. Some of these approaches are promising, but the toxicity of certain reactive transition metal compounds and the cost of wood modification and grafting have restricted their commercial applications. Hence, more cost-effective and environmentally friendly methods of protecti...
Chunling Liu, A Ahniyaz, P Evans
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
Comparative Study of Heat Treatment of Beech Wood in Hot Water and Steam Medium
2010 - IRG/WP 10-40536
Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Heat treatments of beech wood in 2 different mediums (hot water and steam) in 180ºC were compared in physical, mechanical and anatomical properties. Mass loss in hydrothermally treated wood was higher than hygrothermally treated samples. Mechanical properties (MOR, MOE and CS)...
A Talaei, K Yaghoobi, A N Karimi
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
Quantification of four dark colored mould fungi by real time PCR
2011 - IRG/WP 11-10754
Coated wooden claddings in building facades are widely used in the Scandinavian countries, and are often preferred to other materials. Wood is facing increasing competition from other materials that are less labor intensive at the construction site and materials with less demand for maintenance thru service life, and makes further development of wooden claddings essential. Growth of discoloring mo...
E Larnøy, L Ross Gobakken, A M Hietala
Methods of field data evaluation - time versus reliability
2011 - IRG/WP 11-20466
Field testing of wood and wood-based products is so far the most reliable way to get information on performance with respect to durability and expected service life. However, field trials are extremely time and cost consuming. The main objective of the present study was to investigate possible correlations between early stages of decay, preferably during the first 5 years, and the actual service l...
P Larsson Brelid, C Brischke, A O Rapp, M Hansson, M Westin, J Jermer, A Pilgård
Effects of nano-silver on brittleness of heat-treated solid woods
2011 - IRG/WP 11-40572
The present study is aimed at the effect of heat-treatment of normal as well as nano-silver-impregnated Populus nigra, Populus deltoides, and Fagus orientalis on brittleness. Specimens were impregnated with 200 ppm water-based solution of nano-silver particles under 3 bars in a pressure vessel using empty-cell process. For heat treatment, both nano-silver-impregnated and normal specimens were kept...
H Reza Taghiyari, B Moradi Malek, A Karimi