Your search resulted in 183 documents. Displaying 25 entries per page.
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
Surface Characteristics of Southern pine treated with Eastern red cedar oil
2008 - IRG/WP 08-40393
Treatment of wood with various chemicals play an important role on their surface characteristics including as roughness and hardness for further processing such as finishing and machining. The objective of this study is to evaluate surface roughness of Southern pine (Pinus taeda L.) treated
with oil extracted from eastern redcedar (Juniperus viginiana L.). Both tangential and radial surfaces of...
S Hiziroglu
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
Performance of Fasteners in Treated Wood: A Comparative Study
2009 - IRG/WP 09-40465
Fastener performance is an important property for treated wood. Published data on screw and nail performance for different preservative systems currently on the market are, however, limited. In this study, screw and nail withdrawal strength for southern pine wood treated with ACQ (above ground and ground contact), MCQ (above ground and ground contact), borate (disodium octaborate tetrahydrate – ...
Q Wu, T Shupe, J Curole, K Ragon, M Voitier, M Freeman, D Ring
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
Decay Resistance of Maple (Acer Insigne) Wood Against White Rot
2010 - IRG/WP 10-10740
In this study, the decay resistance of maple (Acer insigne) in natural state and treated with ACC (Acid copper chromate) was investigated against the white rot fungus (Coriolus versicolor). ACC is a kind of water borne preservatives that was used in this study for treating specimens under vacuum and pressure (Bethell procedure) with 3 percent concentration. In conducting mentioned evaluation, koll...
V Tazakor Rezaei
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
The effects of acetylation level on the growth of Postia placenta
2011 - IRG/WP 11-10751
To understand the defence mechanisms utilized by decay fungi when exposed to different wood protection systems the study of gene expression can give us some answers. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by differen...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II
Thermally modified timber (TMT) for decking applications – determination of relevant surface properties
2011 - IRG/WP 11-40544
In recent years thermally modified timber (TMT) entered various market segments. It is used for facades, horticultural equipment, garden furniture, and also for kitchen and bathroom cabinets. However, flooring turned out to be the most important application for TMT, either as interior parquet or as exterior decking. Besides durability and dimensional stability, which had been the initial target pr...
L Meyer, C Brischke, C R Welzbacher
Physical properties of Pinus radiata veneers modified with hexamethoxymethyl melamine prepolymers
2011 - IRG/WP 11-40551
Prepolymers containing hexamethoxymethyl melamine and either sucrose (Suc-HMMM) or polyvinyl alcohol (PVA-HMMM) were prepared by acid catalysis under reaction conditions optimised with respect to stiffening effect when introduced into Pinus radiata veneers by vacuum impregnation and cured by hot pressing at 150C. Maximum increases in MOE were 20% for Suc-HMMM (50% WPG), 22% for PVA-HMMM (...
C Molloy, W Rae, S Connor, T Henderson, A Siraa
Effect of Nano-silver Treatment on Densified Poplar Wood Properties. Part Two: Spring Back, Compression set, Impact Load Resistance and Hardness
2011 - IRG/WP 11-40568
This paper is the second part of the study of applying nano-silver treatment before densification of poplar wood (Popolus alba). The specimens were prepared in four groups of: 1) nano-silver impregnated 2) water impregnated 3) dried with no impregnation and 4) the control specimens. The impregnation process was done by empty cell process. Then, the groups of 1 to 3 were compressed in a hot press a...
G Rassam, H Reza Taghiyari, B Jamnani, M Ali Khajeh
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
Laboratory and Field evaluation on Natural Resistance and Feeding Preference of Different Wood Species to Subterranean Termites (Isoptera: Rhinotermitidae, Termitidae) in Pakistan
2012 - IRG/WP 12-10769
The resistance of twenty four different woods to attack and damage by subterranean termite species Heterotermes indicola (Wasmann) and Coptotermes heimi (Wasmann) was evaluated by choice and no choic in laboratory and field trials. Mean wood mass loss was calculated for both laboratory and field trials results using Analysis of Variance (ANOVA). Mean percentage termite mortality was calculated fo...
S A Malik; F Manzoor, B M Ahmed (Shiday)
Wood decay enzymatic ability of Fusarium circinatum
2012 - IRG/WP 12-10777
There exists pathogens that attack standing trees of forests, and do not usually thrive once the tree is felled. However, occasionally they can be present in a latent state in the wood and can spread and affect new areas with economic, ecological and social consequences. Fusarium circinatum is a fungus that causes “pitch canker” in pine species, and is considered a quarantine organism within t...
M T Troya, F Llinares, Y Serrano, M Conde
Variation in two Postia placenta strains, MAD-698-R and FPRL 280 – mass loss, DNA content and gene
2012 - IRG/WP 12-10781
Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and brown rot fungi are also largely responsible for the destructive decay of wooden structures. The aim of this study was to compare two commonly used strains of Postia placenta – MAD-698-R and FPRL 280. Scots pine sapwood samples were exposed for two and eight weeks to both fungal strains. The following was inv...
N Thaler, G Alfredsen, C G Fossdal
The effects of acetylation level on the growth of Postia placenta over 36 weeks
2012 - IRG/WP 12-40589
Genomic sequencing gives us a tool to systematically and rapidly discover novel genes, how their products function in the cell, and explore their interactions. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by different wood...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II
Treating Bambusa vulgaris with neem seed oil against basidiomycetic biodegradation
2012 - IRG/WP 12-30608
Realising maximum benefits from bamboo stems/culms in Nigeria are presently constrained by their almost non-acceptance for applications in most structural and construction purposes, except in comparatively low quality and some temporary applications, such as scaffolding, owing to their susceptibility to easy destruction by agents of biodegradation as a result of their poor inherent natural durabil...
A A Erakhrumen