Your search resulted in 1150 documents. Displaying 25 entries per page.
Assessment of untreated Papua New Guinea timbers against subterranean termites. Final report
1993 - IRG/WP 93-10041
Four years after the exposure of eight timber species of varying density against subterranean termites in a field trial, Kwila was still generally sound while Taun, Malas and PNG Walnut were beginning to be attacked slightly to moderately. Calophyllum, Kamarere, PNG Beech and White Cheesewood were severely attacked and failed. Results after the period of exposure shows that Kwila rates highly as t...
H C Konabe, M Rokova
Micromorphology of Schizophyllum commune attack in pine (Pinus sylvestris) wood
1983 - IRG/WP 1184
The decay pattern caused by Schizophyllum commune in pine latewood tracheids was studied using both light and transmission electron microscopy. The attack began as isolated concentric slits within the S2 layer with extensive lamellation and separation of individual wall layers observed in subsequent stages of decay. The slits resulting from attack appeared to be formed in thin, regular concentric ...
T Nilsson, G F Daniel
Water-Borne Copper Naphthenate: An Emerging Wood Preservative
2002 - IRG/WP 02-30280
Waterborne copper naphthenate (WB Cu-N) was used to treat southern yellow pine (Pinus spp) and red maple (Acer rubrum) stakes. The treated stakes were exposed in test sites located in Florida, Michigan and Mississippi for 3 to 6 years. Copper Chromium Arsenate (CCA),
Ammoniacal Copper Quat (ACQ) and Oil-borne Copper Naphthenate (OB Cu-N) were also used to treat some stakes for comparison. Results...
P Nzokou, D P Kamdem, M H Freeman
Durability of heat-treated wood
1999 - IRG/WP 99-40145
Heat-treated wood from the French process were laboratory tested against decay using agar block test and a modified soil block test. Water absorption, bending strength, lignin content and acid number were also determined to evaluate the effect of heat treatment. Heat treated samples exhibit a higher lignin content and a lower acid number compared to untreated control indicating the degradation of ...
D P Kamdem, A Pizzi, R Guyonnet, A Jermannaud
The Protection of Wood with Oxy-aluminium Compounds
2002 - IRG/WP 02-30286
Wood inorganic composites (WICs) containing aluminium compounds were developed and tested in relation to some essential requirements of preservative treated wood. Four different oxy-aluminium treatments were developed and identified according to the final insoluble compounds formed (sodium aluminate, aluminium hydroxide, magnesium aluminate and aluminium borate) in wood. Vacuum impregnation or dou...
F A Ximenes, P D Evans
A dynamic approach to assess the modulus of elasticity in wood decay testing
1998 - IRG/WP 98-20139
In this study, the changes in elastic behaviour and mass losses of different hardwood and softwood species exposed to decay in a laboratory soil tests were assessed. Wood decay was monitored using different assessment methods, namely: mass loss and changes in elastic behaviours (MOE) determination. Elastic changes were determined by static and dynamic methods, for the latter, acoustic technique wa...
L Machek, H Militz, R Sierra-Alvarez
Susceptibility of CCA treated North American hardwoods to Chaetomium globosum decay
1998 - IRG/WP 98-10278
Seven species of hardwood, Beech (Fagus grandifolia), Basswood (Tilia americana), Maple (Acer rubrum), Oak (Quercus rubra), Trembling Aspen (Populus tremuloides), White birch (Betula papyrifera) and Yellow poplar (Liriodendron tulipifera) were vacuum or pressure impregnated with CCA, at four retention levels. The CCA was allowed to fix in the wood at 35°C. Red pine (Pinus resinosa) was also inclu...
U Srinivasan, Y T Ung, P A Cooper
Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition
2003 - IRG/WP 03-40259
A limited understanding of the fundamental aspects of supercritical fluid (SCF) impregnation in wood remains an obstacle to the development of this technology. Developing a better understanding of the effects of various process parameters on treatment results would facilitate more rational development of SCF impregnation. In this project, the effect of treating period and specimen length on su...
Sung-Mo Kang, J J Morrell
A non-pressure method of protection based on hurdle theory to control the spectrum of internal environmental factors which affect the decay of poles in soil contact
1993 - IRG/WP 93-20005
A field trial was conducted to establish whether superficial barrier linings on poles in soil contact could function as environmental hurdles against the growth of biological agents and thus provide preventative methodology to preclude premature failure of vineyard poles under flood-irrigation. Assessment after 52 weeks exposure to the prevailing conditions and sub-tropical environment showed that...
A A W Baecker
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Factors affecting decay rates in a fungus cellar II
1986 - IRG/WP 2259
Tests were initiated to investigate the influence of various factors on the decay rate in a "Fungus Cellar". Birch and pine stakes treated with chromated copper arsenate and didecyldimethyl ammronium chloride, as well as untreated control stakes, were incubated in two soils in a Fungus Cellar test and installed at two field sites for comparative purposes. The visual rating vs actual stake weight l...
P A McKaig
Comparative study of the degradative ability of autochthonous and standardized strains of wood decay fungi
1996 - IRG/WP 96-10178
This study is intended to assess the biomass, the extracellular protein production, and the carbohydrate degradating ability of three standarized (Chaetomium globosum, Trametes versicolor and Gloeophyllum trabeum) and six autochthonous wood decay fungi strains, with unknown degradating effects. The carbohydrate sources used were those that are usually found in wood cells (glucose, galactose, manos...
F Llinares, D Muñoz-Mingarro, J E Garcia de los Rios, M T De Troya, M Yuste, F Rubio, F Alvarez, P Jiménez, C Rodríguez-Borrajo, A M Navarrete
Soil-bed decay resistance evaluation of strandboards treated with preservative at different points of the manufacture process after 18 months exposure
2002 - IRG/WP 02-40230
Strandboards were treated with a copper-boron water-based preservative at different points of manufacture process namely, green strand diffusion, vacuum, spray application in the resin blender and post manufacture heat and cold quench.
Preservative was applied to achieve five different retentions (0, 1.5, 3, 6, 12 kg m-3). The modulus of rupture and modulus of elasticity were assessed before expo...
G J Goroyias, M D C Hale
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 1: Optimisation of the extraction conditions
2000 - IRG/WP 00-30238
As the first phase of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, several solvents and extraction methods were evaluated, initially in the laboratory and then at pilot industrial scale. Extracts were compared by crude total dissolved solids content, by chemical analysis using GC-MS and LC-MS, and by laboratory...
M J Kennedy, Hui Jiang, L M Stephens
Targeted inhibition of wood decay (Using everything but the kitchen sink)
1997 - IRG/WP 97-10203
Low molecular weight oxidative decay agents have been implicated in the degradation of wood by brown-rot decay as evidenced by chemical analysis of brown-rotted wood and detection of oxalic acid and hydroxy radicals. Fenton chemistry (H2O2 / Fe++) is often proposed as the mechanism for generating hydroxy radicals. Previous authors have shown iron to enhance the brown-rot hydrolysis of wood, while ...
F Green III, T A Kuster, T L Highley
Fungal colonisation of the keelson and associated structures of a nineteenth century wooden frigate: Concepts of community structure and development
1994 - IRG/WP 94-10072
The early stages of microbial colonization and succession of wooden surfaces exposed to the sea have been extensively studied as have the community structures of archaeological timbers subjected to submergence and then retrieval from the sea. The frigate UNICORN, a largely intact 19th century wooden ship based in Dundee, Scotland, provides the microbial ecologist with a unique opportunity to study...
N A White, J W Palfreyman, G M Smith
Evaluating the resistance of wood-based panel products to fungal attack
1995 - IRG/WP 95-20071
At present there is considerable disagreement among national research institutes within Europe and panel product manufacturers on the most appropriate method of testing and indeed the need for specific biological durability testing. This paper seeks to place before a broader international audience, the issues related to development of a European standard for evaluating the resistance to fungal dec...
R G Lea, R W Berry
Detection of wood decay fungi in wood using a PCR-based analysis
1998 - IRG/WP 98-10279
We have developed a DNA-based assay to reliably detect brown rot and white rot fungi in wood at different stages of decay. DNA, isolated by a series of CTAB and organic extractions, was amplified by the polymerase chain reaction using published universal primers and basidiomycete-specific primers derived from ribosomal DNA sequences. We have surveyed 7 species of brown rot fungi, 7 species of whit...
C Jasalavich, A Ostrofsky, J Jellison
On the resistance of consolidated ancient wood against Serpula lacrymans (Wulfen: Fr.) Schroeter
2000 - IRG/WP 00-10348
Structural timbers and other wood objects of cultural value in historical buildings and museums are often attacked by wood-destroying fungi. The aim of conservators is to preserve such damaged timbers and prevent further biodeterioration by impregnation with consolidants. There is little knowledge of the resistance of consolidated timber and art objects to a new attack by wood-destroying fungi. Br...
W Unger, A Unger, U Schiessl
Mechanisms of Protection by NHA Against Fungal Decay
2002 - IRG/WP 02-10429
Treating wood with the water-borne sodium salt of N'-N-naphthaloylhydroxylamine (Na-NHA) protects wood against decay and termite damage. Initial testing indicated little or no inhibition of sapstain fungi, molds, or soft-rot fungi by Na-NHA, suggesting that the
mechanism by which this compound protected wood was complex and not that of a broad-spectrum biocide. Previously, we (Green et...
F Green III, W Henry, T Schultz
Aboveground Microbial Decay Test of Biocide Treated and Untreated Wood Exposed to Danish and Humid Tropical Climates
2004 - IRG/WP 04-20306
A co-operative study was initiated to compare the aboveground field decay test of untreated and preservative-treated timbers under Nordic (Danish) and a representative humid tropical (Malaysian) environment according to CEN standard method. Matched specimens of untreated and both preservative-impregnated and surface-treated wood were simultaneously exposed at The Danish Technological Institute (DT...
A H H Wong, N Morsing, K H Henriksen, S Ujang
Difference of CCA efficacy among coniferous wood species
1990 - IRG/WP 3601
Wood blocks of Cryptomeria japonica, Tsuga heterophylla, and Pinus radiata successively extracted with n-hexane, ether, and methanol were treated with various concentrations of CCA type 3, which were subjected to the decay by Tyromyces palustris. The weight loss were different among species and kinds of extraction. Cryptomeria japonica treated with CCA had higher fungal resistance than Tsuga heter...
K Yamamoto, M Inoue
Resistance to decay of particle boards: Presentation of a test method
1986 - IRG/WP 2260
The experimentations were undertaken on particle boards 35 and 50 mm thick. The rot resistance tests were carried out on specimens whose dimensions were 600 x 75 x 35 mm³ for particle boards 35 mm thick and 800 x 75 x 50 mm³ for particle boards 50 mm thick according to a method derived from the one described in the documents IRG/WP/2214 and IRG/WP/2243. Two exposure periods were used: 12 and 16 ...
G R Y Déon, N Trong
Computer-assisted ranking of potential biocontrol fungi based on data from laboratory screening trials
1993 - IRG/WP 93-10023
Forty two fungal isolates were screened for antibiotic activity. In these sceering tests inhibition of target wood decay fungi was expressed as a series of numerical scores for each isolate. These scores, along with values for 5 other charactetistics, were used to assess the isolates. Using selection indices, isolates were judged on the basis of all the characteristics combined and, ranked in orde...
M W Schoeman, D J Dickinson
Chelator production and cellobiose dehydrogenase activity of wood inhabiting fungi
2000 - IRG/WP 00-10363
Multiple components have been postulated to be involved in the Fenton-based biological degradation of wood by brown rot fungi. Chelators have been implicated in essential iron reduction steps. Cellobiose dehydrogenase activity and quinone reducing activity have also been implicated in brown rot biodegradation. When biochelator production by three white rot fungi, three brown rot fungi and three wo...
Weihong Qi, J Jellison