Your search resulted in 306 documents. Displaying 25 entries per page.
Artificial weathering exposure as an alternative for standard ageing according to EN 84 (leaching) and EN 73 (evaporation)
2002 - IRG/WP 02-20254
In order to verify potential weaknesses of wood preservatives fungal tests are carried out after ageing of wood preservative treated test blocks. The European standard EN 599 as a framework for efficacy assessment of wood preservatives includes the use of two ageing methods prior to fungal testing, namely a leaching method (EN 84) and an evaporation method (EN 73). The European research project "F...
J Van Acker, M Grinda, D J Dickinson
Effect of origin and orientation of Radiata pine substrates on the development of fungal degrade
2000 - IRG/WP 00-30221
The objective of this study was to determine the influence of different radiata pine substrates on colonisation by sapstain fungi. Freshly-cut branch wood, stem wood and sawn lumber were used to prepare test samples with the largest wood surface area showing a transverse, radial or tangential face. Test samples were evaluated against sapstain fungi using a rapid laboratory antisapstain screening m...
B Kreber, D R Eden, C M Chittenden, B Carpenter, J G Van der Waals
Comparison of two laboratory methods for screening potential anti-sapstain chemicals
1993 - IRG/WP 93-10036
Two methods were used to screen a number of potential anti-sapstain chemicals in the laboratory. In one method miniature boards of freshly felled Scots pine sapwood were dip treated with the candidate chemical, sprayed with a suspension of stainers or moulds and incubated for five weeks. In the other method antibiotic assay discs were treated with precise quantities of chemical, plated out on malt...
S M Gray, D J Dickinson
Effects of air-seasoning on fungal colonization and wood strength of Douglas fir poles
1987 - IRG/WP 1315
Air seasoning economically reduces the moisture content of Douglas fir poles before pressure treatment with preservatives. Advanced decay in poles in service has resulted when decay fungi (Basidiomycetes) colonized poles during air-seasoning and survived the treatment process. These problems have led to recommendations to severely limit this practice. To determine the role of these fungi in peeled...
J J Morrell, M E Corden, R D Graham, B L Kropp, P Przybylowicz, S M Smith, C A Sexton
The influence of staining fungi on the decay resistance of wood treated with alkylammonium compounds
1984 - IRG/WP 3308
Although found to be very effective in laboratory tests, alkylammonium compounds (AAC's) have failed to perform as well in field stake tests. Examination of leachability showed that this was not the cause. The present study investigated the possibility that staining fungi, (which have been observed to rapidly infect the field stakes), degrade the AAC wood preservative. Soil-blocks were tr...
J N R Ruddick
Comparison of the in-ground performance of pigment emulsified creosote (PEC) and high temperature creosote (HTC)
2000 - IRG/WP 00-30217
A long-term field trial was conducted in Australia to compare the in-ground performance of two oil-borne preservative formulations, conventional high temperature creosote (HTC) and a modified creosote formulation, pigment emulsified creosote (PEC). Three retentions (50, 100 and 200 kg/m³) were targeted for each formulation. An additional retention of PEC formulation (308 kg/m³), which contained ...
J W Creffield, H Greaves, N Chew, N K Nguyen
The potential application of rapid gas-chromatographic assay of microbial respiration to the monitoring of wood decay in field trial situations
1983 - IRG/WP 2196
Gas chromatographic detection of microbial activity (C02 production) within stakes in a field trial situation would appear to provide a sensitive, non-destructive and relatively rapid method for the quantitative assessment of preservative treatments. Most consistent results were obtained when stakes were removed from the soil, washed, saturated with water and incubated in sealed PVC tubes at 25°C...
M A Line
Degradation of polycyclic aromatic hydrocarbons by laccase
1998 - IRG/WP 98-10267
The degradation of polycyclic aromatic hydrocarbons (PAH) by laccase was investigated. Laccase catalyzed oxidation of phenanthrene, solubilized in the surfactant Tween 20, exhibited an absolute requirement for the mediator compound 1-hydroxybenzotriazole. When Tween 80 was used as the solubilizing agent, the oxidation rates were more than six times higher as compared to Tween 20. Using the thiobar...
S Böhmer, E Srebotnik, K Messner
Fungal detoxification of organotin biocides
1985 - IRG/WP 1258
The ability of a range of wood decaying fungi to inactivate bis(tri-n-butyltin) oxide (TnBTO) in the extracellular growth medium, in stationary liquid culture was determined. A distinction between the ability to tolerate the fungicide and to inactivate it was made: the white-rot organism Coriolus versicolor being the most efficient inactivator. In an attempt to determine the extracellular agents r...
P S Belford, D J Dickinson
Possible durability transfer from durable to non durable wood species. The study case of teak wood
2001 - IRG/WP 01-10392
Teakwood is well known for its excellent natural durability, mostly due to its high proportion of extracts. Amongst these extracts, quinones, and more precisely some naphtoquinones (such as lapachol) and anthraquinones (such as tectoquinone) appear to play a crucial role in the resistance to wood decay organisms. At a laboratory scale, sawdust from malaysian teak heartwood has been extracted under...
M-F Thévenon, C Roussel, J-P Haluk
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
A study of fungal biodeterioration in unseasoned, packaged hem-fir lumber
1978 - IRG/WP 2116
This study was undertaken to determine the extent of biodeterioration that could occur within British Columbia (BC) prior to the export of packaged Canadian Lumber Standard Hem-Fir (Tsuga heterophylla, Abies amabilis and small amounts of Abies grandis). By examining the anti-stain treatments received by the lumber and identifying and characterizing the organisms responsible for the biodeterioratio...
P W Perrin, A J Cserjesi
Resistance of acrylic paints on wood against growth of the rot fungus Dacrymyces stillatus
1990 - IRG/WP 2345
In the last few years the presence of the rot fungus Dacrymyces stillatus has been repeatedly confirmed in external wood panels, particularly from wood painted with water based paints. A laboratory method for testing of the fungal resistance of paint films on wood has been developed.This method has been used to test the efficacy of the fungicides Parmetol DF 18 and Parmetol HF 25 against attack by...
J Bjurman
Occurrence and importance of various types of fungal and bacterial decay in CCA-treated horticultural pine posts in New Zealand
1984 - IRG/WP 1234
A detailed microscopical examination has been carried out on samples taken from CCA-treated pine posts exposed in horticultural soils. The following decay types were observed: white rot, brown rot, soft rot, tunnelling bacteria, cavitation bacteria, and bacterial erosion. The occurrence and importance of the various decay types between different regions, and plots within a specific region, varied ...
T Nilsson
A biochemical explanation for the observed patterns of fungal decay in timber
1980 - IRG/WP 1111
Experiments designed to compare the degree of localization of the cellulase enzymes of some white, brown and soft rot organisms are described. The site and nature of binding of the enzymes is discussed. The technique is ellution of mycelium grown in liquid culture with a variety: of agents including acetate buffer, carboxymethyl cellulose solution, borate/glycerol buffer and urea. The mycelium was...
N B Green, D J Dickinson, J F Levy
International comparison of three field methods for assessing the in-ground resistance of preservative-treated and untreated wood to termites and fungal decay – Summary of observations after five years
2003 - IRG/WP 03-20261
Results are presented from a five-year study conducted in five locations in Australia, Thailand and the USA. Three methods of exposure were assessed (below-ground, graveyard and ground contact) for evaluating the in-ground termite and decay resistance of Pinus radiata D. Don sapwood stakes that had been vacuum pressure impregnated with CCA (Type C) and ACQ (Type D) each at two nominal retentions (...
M Lenz, J W Creffield, T A Evans, B M Kard, C Vongkaluang, Y Sornnuwat, A F Preston
Imaging fungal deterioration of wood using x-ray microtomography
1997 - IRG/WP 97-10240
Nondestructive tomographic images of solid Southern yellow pine (SYP) wood and SYP during deterioration by wood decay fungi were obtained by using a new class of synchrotron X-ray computed microtomography (CMT). The CMT images will provide information about spatial relationship between degrading fungi and wood structures. Wood samples were scanned with synchrotron-generated X-rays at high resoluti...
B Illman, B A Dowd
Effects of the specimen position on fungal colonisation and wood decay by en 113 test fungi
1998 - IRG/WP 98-20136
For testing wood preservatives according to EN 113 it is common practice to plant the test blocks on neutral supports in order to prevent (1) a diffusion of chemicals into the agar medium and (2) an excessive moistening of the specimens. The procedure was employed in EN 350-1 for testing the natural durability of solid wood.
It turned out to be of problematic nature because of the individual requ...
G Kleist, M-T Lenz, R-D Peek
Fungal decay resistance of Rubber wood treated with heartwood extract of Rosewood
2005 - IRG/WP 05-30367
Alcoholic extract of Dalbergia latifolia heartwood was studied for its toxicity towards wood decaying fungi. Rubber wood blocks were treated with this extract to three different retention levels (0.1%, 0.2% & 0.5%) and the treated wood blocks were assessed for their resistance towards two white rot and two brown rot fungi. Treated blocks showed improved resistance over the control blocks. At 0...
A K Sethy, H C Nagaveni, S Mohan, K T Chandrashekar
Anti-fungal properties of pyrolytic oils derived from softwood bark
2000 - IRG/WP 00-30218
Thermal decomposition of balsam fir and white spruce mixed bark residues at 450°C and under vacuum (< 20 kPa abs.) results in high yields of pyroligneous liquors rich in phenolic content. This vacuum pyrolysis process has been scaled-up to a pyrolysis plant with a feed capacity of 3.5 t/h of softwood bark, which is the largest plant of this type in the world. The pyrolytic aqueous condensates ...
D Mourant, Dian-Qing Yang, Xiao Lu, C Roy
Evaluation of white-rot fungal growth on Southern Yellow pine wood chips pretreated with blue-stain fungi
2000 - IRG/WP 00-10349
White-rotting basidiomycetes do not colonize on southern yellow pine. This study seeks to reduce the resinous extractive content of southern yellow pine by treating it with blue stain fungi. The mycelial growth of wood-inhabiting ligninolytic white-rot fungi can be achieved on pretreated southern yellow pine wood. Aureobasidium, Ceratocystis, and Ophiostoma spp. removed 70% to 100% of the extracti...
S C Croan
Fungal decay of acrylate treated wood
2004 - IRG/WP 04-30357
Natural durability of wood species is variable. Chemical wood preservatives, such as biocides are necessary for extension of their service life. Many methods have been developed to increase the resistance of wood and wood products against wood-destroying organisms during the last years. The most frequently used methods are chemical and thermal modification of wood. In wood modification the basic c...
Z Tiralova, L Reinprecht
In situ testing the influence of melamine resins on the enzymatic activity of basidiomycetes
1999 - IRG/WP 99-30194
Waterbased methanol etherificated melamine formaldehyde resins have the potential to increase the resistance of impregnated wood against wood destroying fungi. The mechanism of the increased wood durability is not clear yet. In the present paper the possible interference of melamine resins with wood degrading enzymes of Coniophora puteana and Trametes versicolor was investigated as a possible cont...
D Lukowsky, F Büschelberger, O Schmidt
Control of wood biodeterioration by fungal metabolites
1992 - IRG/WP 92-1527
Treating wood with different conventional preservative chemicals for protection and economic utilisation is well known. Tough some of these chemicals are toxic to skin, their use as wood preservative is unavoidable as they should be toxic to biodeteriorating organisms also. Recent advances in chemistry of natural products enabled the use of wood extractives as biocidal compounds against biodeterio...
H S Ananthapadmanabha, H C Nagaveni, V V Srinivasan
Physiological properties of fungal test strains according to the European Standard EN 113
1986 - IRG/WP 2258
For the discussion of the European standard EN 113 the EMPA's procedure of culturing the test fungi and the corresponding virulence of the test fungi as well as the wood moisture content at the end of the test are shown. It is mainly shown that within the standard the choice of the solvent may not be left at the test lab if reproducible results shall be obtained. The different solvents in...
E Graf, B Zgraggen, P Manser