Your search resulted in 43 documents. Displaying 25 entries per page.
Investigation of the suitability of silver fir (Abies alba Mill.) for thermal modification
2004 - IRG/WP 04-40275
In this study the suitability of silver fir (Abies alba Mill.) was examined for thermal modification. Comparative experimental investigations were performed with silver fir and Norway spruce (Picea abies Karst.) after thermal treatments. Besides properties, which characterize the quality of heat treatments, like dimensional stability and resistance against fungal attack, strength properties of the...
C Brischke, A O Rapp
Biological control with Trichoderma harzianum in relation to the formation for spores the production of soluble metabolites
1994 - IRG/WP 94-10073
The amount of spores produced by three strains of Trichoderma harzianum on the aerial mycelium of agar cultures and in shake cultures, respectively, correlated with the inhibition zones exerted against Phanerochaete chrysosporium in an agar diffusion test. The amount of soluble antifungal metabolites as well as the protein content also correlated with the inhibition zones and the amount of spores ...
J Bürgel, E Horvath, J Haschka, K Messner
Decay patterns observed in butylene oxide modified ponderosa pine attacked by Fomitopsis pinicola
1983 - IRG/WP 1183
Small blocks of ponderosa pine chemically modified by butylene oxide to three different weight percent gains (WPG) were decayed for 2 months with the brown rot fungus Fomitopsis pinicola. Wood substance loss and the type of decay pattern recognised were fairly similar both for control and blocks treated to 8 and 15 WPG. No difference in attack was observed between radial or tangential walls in lat...
T Nilsson, R M Rowell
The formation of organotin carboxylates in bis(tributyltin) oxide - treated Pinus sylvestris sapwood
1990 - IRG/WP 3618
Tributyltin compounds have been successfully used for many years as wood preservatives, although their chemical nature in timber have not been fully elucidated. This study by 119Sn and 13C NMR spectroscopy has shown that, on impregnation into Pinus sylvestris sapwood, bis(tributyltin) oxide, (Bu3Sn)2O, is rapidly converted to tributyltin carboxylates, Bu3SnOCO·R, via reaction with components of t...
S J Blunden, R Hill
Suppression of aerial hypha formation by spent culture filtrate of a non-degradative strain of Postia placenta
1991 - IRG/WP 1498
ME20, a wild-type monokaryotic strain of the brown-rot fungus Postia placenta, does not cause significant weight losses in standard soil-wood block decay tests and fails to form aerial hyphae in liquid and agar culture. This abnormal morphological feature may be caused by the same aberrant physiology that prevents the strain from degrading wood efficiently. ME20 releases elevated levels of the aut...
J A Micales
Ultrastructural observations on wood-degrading erosion bacteria
1986 - IRG/WP 1283
G F Daniel, T Nilsson
Artificial drying of impregnated wood
1987 - IRG/WP 3448
Sawn timber (Pinus Sylvestris) of dimension 50x150 mm was impregnated with CCA by a full-cell process. The timber was then dried in a conventional kiln or a special vacuum kiln where the timber was dried by circulating superheated steam. Drying time was 16 days and 2 days respectively. The aim of the investigation was to compare the physical appearence of the wood after drying by the two methods w...
Sludge formation in timber treatment with CCA preservatives. Origin and elimination
1984 - IRG/WP 3276
The exact distributions between lignin and holocellulose and retentions on wood of copper, chromium and arsenic as a function of various sets of conditions in a factorial experiment in which combinations of three temperatures of treatment, three CCA solution concentrations, four pH's of the initial CCA solution and two timber species, namely Pinus radiata and Eucalyptus grandis, are repor...
A Pizzi, W E Conradie, A Jansen
Formation of soft rot cavities in relation to concentric layers in wood fibre walls
1983 - IRG/WP 1185
A large number of timber species attacked by soft rot have been examined using light microscopy. The S2 layers in a large number of the timbers exhibited special structural features in the form of thin concentric layers. Several observations indicate that these layers may be characterised as "weak" zones by being more easily degradable than the surrounding wall layers. The chemical structure of th...
T Nilsson, G F Daniel
Termite-tunnels formation on the surface of termite-resistant wood species in field sites
2001 - IRG/WP 01-10400
In this report, termite-tunnels formation by the subterranean termite, Coptotermes formosanus Shiraki on the surface of termite-resistant wood species, namely, Hinoki (Chamaecyparis abtsu), Yoshino Hinoki (Chamaecyparis abtsu), Miyazaki Hinoki (Chamaecyparis abtsu), Hiba (Chamaecyparis abtsu) and Japanese cedar (Cryptomeria japonica) was conducted in field sites. Westernhemlock (Tsuga heterophylla...
Y Kadekaru, K Kinjo, S Yaga
Biochemical relationships between biodegradation of cellulose and formation of oxalic acid in brown-rot wood decay
1991 - IRG/WP 1472
Non-enzymic hydrolysis of cellulose with low concentrations of oxalic acid was examined. The incubation of pine wood pulp with 1% oxalic acid (pH 1.3) at 35°C for 4 weeks reduced the original viscosity to 60%. Reducing sugars were liberated from various cellulosic samples by the oxalic acid treatment. However, crystallinities of cellulose in those samples did not change before and after the treat...
M Shimada, Y Akamatsu, A Ohta, M Takahashi
Diffuse cavity formation in soft rot of pine
1992 - IRG/WP 92-1541
A new type of soft rot of southern pine longitudinal tracheids is described. In this type, soft rot cavities form by diffuse degradation of the S2 cell wall layer by hyphae growing within the cell wall. Erosion is diffuse and irregular as opposed to the restricted, periodic erosion typical of type 1 soft rot cavity formation. Proboscis hyphae remain small (diameter 0.6 to 0.8 µm) and rapidly auto...
S E Anagnost, J J Worrall, C J K Wang
Characterization of checks and cracks on the surface of weathered wood
2000 - IRG/WP 00-40153
The surface roughness of unweathered and untreated pine; unweathered copper chromium arsenate type C (CCA) - treated pine; weathered CCA-treated pine; and weathered CCA-plus-water-repellent (WR) - treated pine was evaluated by a stylus tracing method. Surface roughness parameters Ra, Rz, Rmax, Rk, Rpk, and Rvk were measured. Ra, Rpk, and Rvk were the most appropriate parameters for describing modi...
D P Kamdem, Jun Zhang
Basisiospore production by Lentinus lepideus in vitro
1987 - IRG/WP 2276
Evaluation of fungicides active against the lower fungi by spore based bioassays is very common. Possibilities of using similar assays to evaluate preservatives against brown rot and white rot fungi, especially for use in above ground constructions, are limited by the lack of methods for production of basidiospores. Tested media containing glucose 10-30 g/l and ammonium tartrate concentrations 2-2...
Timber preservatives and corrosion
1983 - IRG/WP 3228
A survey of preservative treated timber commodities has illustrated problems that may be caused by corrosion. After treatment, timber should be compatible with commonly used fasteners. Whilst many corrosion methods have been used in the past, no standardized method is used by workers in timber preservation. The Queensland Department of Forestry is developing laboratory test methods for assessing c...
R I Davis
Regulation of hyphal sheath formation iron-chelator production by the brown rot fungi Gloeophyllum trabeum and Postia placenta
1994 - IRG/WP 94-10074
Hyphal sheath formation and iron-chelator production by liquid cultures of the brown rot fungi Gloeophyllum trabeum and Postia placenta were monitored over time. The effects of incubation at various temperatures, pH's and concentrations of iron, manganese and nitrogen were determined. Hyphal sheath production was observed microscopically and quantified with JAVA video analysis. The hyphal...
Y Chen, J Jellison
Formation of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) during the combustion of impregnated wood
1995 - IRG/WP 95-50040-19
Wood waste and industrial wood residues often contain various preservatives. The waste management for these residuals can be recycling, deposition or combustion. Among the three possibilities, combustion seems to be the most efficient way of disposal. To obtain detailed information about emissions of organic compounds with environmental impact, especially polychlorinated dibenzo-p-dioxins (PCDD) a...
T Salthammer, H Klipp, R-D Peek
Fruitbody formation and basidiosporogenesis by the white rot fungus Pycnoporus cinnabarinus
1988 - IRG/WP 1348
Conditions for fruitbody formation by the white rot fungus Pycnoporus cinnabarinus in vitro were outlined. A marked difference in substrate requirements in comparison to previously tested brown rot fungi was revealed. Agar media containing Walseth cellulose and NH4 tartrate at 1 g/l permit profound production of basidiospores particularly at 15°C but only under light treatment. Higher NH4 tartrat...
The effect of storage and subculturing on in vitro fruit body formation and spore production in Gloeophyllum sepiarium and Oligoporus placentus
2001 - IRG/WP 01-20232
Spores are widely assumed to be the main mode of infection of wood in conditions conducive to decay above ground. In order to supply spores on demand as an experimental material, fruiting body and basidiospore production in vitro by Gloeophyllum sepiarium and Oligoporus placentus have been examined. The optimum medium, time to spore production, and duration of fruiting as well as fruiting body sha...
S Choi, J N R Ruddick, P I Morris
Comments on soft rot attack in timbers treated with CCA preservatives: A document for discussion
1982 - IRG/WP 1167
This paper is not based on any particular results but rather on several observations of soft-rot during many years of studies, and on a review of the existing literature. The short time available has unfortunately not permitted a detailed review of the literature. Data and knowledge of important facts are lacking for several aspects of soft-rot attack and for reactions occurring in the wood as a r...
Preliminary observations of the effect of growth ring orientation on the surface checking of flat sawn Southern pine decking
2005 - IRG/WP 05-20313
Checking in decking timber is a serious defect and methods of reducing its severity are required to ensure that wood can compete with alternative decking materials. The first aim of this research was to test the hypothesis that flat sawn Southern pine decking boards with growth rings oriented concave to the exposed surface will develop less severe checking when exposed outdoors than similarly expo...
K Urban, P D Evans
The effect of kerfing on check formation in treated white spruce (Picea glauca) poles
1981 - IRG/WP 3167
62 white spruce poles, 6 m in length, were cut from full size utility poles commercially pressure treated with preservative. 21 of the poles were treated with pentachlorophenol, while of the remainder, all of which were treated with ammoniacal copper arsenate, 22 were kerfed and 19 were unkerfed. The poles were installed in the Westham Island field test site, near Vancouver, and inspected annually...
J N R Ruddick
The susceptibility to sludging of sulfate and oxide CCA
1990 - IRG/WP 3599
Radiata pine sapwood was treated separately with a sulphate CCA-C and an oxide CCA in a pilot scale pressure plant using a full cell process. CCA solutions were recovered from the final vacuum phase, placed in plastic tubes, and their susceptibility to sludging determined by examining changes in solution pH, time required for sludge to form and weight and chemical composition of sludge formed. Sul...
B T Mutandadzi, P D Evans
A physiological role of the glyoxylate and TCA cycles in fruitbody formation of the coppertolerant brown-rot fungus Fomitopsis palustris
2002 - IRG/WP 02-10430
Changes in activity of the representative enzymes involved in biosynthesis of oxalic acid (oxalate) and carbon metabolism of glucose were investigated in relation to the fruit body formation of the copper-tolerant brown-rot fungus Fomitopsis palustris. Changes in specific activities of the two glyoxylate (GLOX) cycle key enzymes (isocitrate lyase (ICL) and malate synthase (MS)), the two oxalate-fo...
Jeong-Jun Yoon, T Hattori, M Shimada
The role of oxalic acid in short fiber formation by the brown-rot fungus Postia placenta
1993 - IRG/WP 93-10028
The mechanism by which brown-rot fungi depolymerize wood and cellulose remains a perplexing problem. Current evidence favors oxidation by low-molecular weight, non-enzymatic fungal metabolites. During attack of cotton cellulose by Postia placenta MAD-698, the degree of polymerization (DP) decreases to limit of degree of polymerization (LODP) over a period of 5-6 weeks with relatively low weight lo...
F Green III, J M Hackney, C A Clausen, M J Larsen, T L Highley