Your search resulted in 3325 documents. Displaying 25 entries per page.
Treatment of wood with formaldehyde. Acid catalysis of the reaction between formaldehyde and wood
1980 - IRG/WP 3146
Formaldehyde reacts with the free OH-groups in wood forming cross-linking bonds. The reaction can be brought about without any catalyst but in that case the activation energy is very high and high temperatures and long reaction times are needed. Normally, the reaction is catalysed by different acids. Acid catalysts, however, tend to degrade the cellulose and the wood matrix causing reduction in th...
T Vihavainen, K Piispanen, P Mansikkamäki
UV-microspectrophotometry of lignin and accessory compounds in wood cell walls of conifers
1999 - IRG/WP 99-20171
The distribution of lignin in the cell wall of conifer tracheids was determined by UV-VIS microspectro-photometer. Wood sections of one micron thickness were measured between the wavelength 240 and 700 nm. Spectral analyses revealed that the conifer lignin associated with the tracheid secondary wall and middle lamella is composed of guiacylpropane units which exhibit a characteristic UV absorption...
G Kleist, G Koch, J Bauch
Remediation of pentachlorophenol- and creosote-contaminated soils using wood-degrading fungi
1994 - IRG/WP 94-50021
Microbiological treatment of hazardous wastes has generally been associated with the use of bacteria. During the past decade a significant body of evidence has accumulated that demonstrates that fungi, in particular white-rot fungi, have the ability to degrade a wide range of hazardous organic compounds (xenobiotics) and thus might also be useful for treatment of materials contaminated with these ...
R T Lamar, T K Kirk
Fungi used in standard tests on the toxicity value of wood preservatives in various European countries
1975 - IRG/WP 255
The aim of the present paper is to make the comparative analysis of test fungi used in various European countries in order to define the toxicity value of wood preservatives against fungi of the Basidiomycetes class. Only the methods with national standard rank, present on the currently binding standards list are taken for consideration. The analysis of similarities and differences in the choice o...
J Wazny
Standardisation of sapstain tests - A challenge
1992 - IRG/WP 92-2403
In the last decade many new anti-sapstain products have been tested world-wide under laboratory and field conditions. Several extensive test programmes have been executed with different non-standardized test methods and procedures, with the result that the biological findings cannot be compared with each other. In this paper, gathered recommendations will be given in order to standardize test meth...
G Rustenburg, C J Klaver
Susceptibility of CCB treated wood to fungal colonization
2003 - IRG/WP 03-10492
CCB treated wood is generally resistant to all wood decay fungi. However, like CCA impregnated wood, susceptibility of CCB treated wood to copper tolerant fungi have been observed. The ability of various brown rot fungal hyphae to penetrate and overgrow the wood samples was investigated. Samples made of Norway spruce (Picea abies) were impregnated with 5 % CCB solution according to the EN 113 proc...
F Pohleven, U Andoljsek, P Karabegovic, C Tavzes, S A Amartey, M Humar
Evaluation of fungal remediation of creosote treated wood
1998 - IRG/WP 98-50101-25
Biotechnological remediation of creosote treated wood may be of interest in connection with novel recycling processes. White rot fungi and/or their ligninolytic enzyme systems are supposed to be valuable tools for such processes. This paper reports about results achieved when creosoted wood was treated in solid substrate fermentation with selected white rot fungi after different extraction procedu...
K Messner, S Böhmer
Using DNA probes to characterize the metabolic pathway of pigment production in several wood-staining fungi
1996 - IRG/WP 96-10146
During shipment and storage, lumber is susceptible to sapstain, a wood discoloration caused by fungi. Currently kiln drying and chemical applications are used to control sapstain. However, the chemicals used to protect wood have a broad range of action, and so can affect other organisms. In addition, in Canada most of these chemicals are under temporary registration. Thus there is a need to develo...
R Eagen, S Riecken, J Kronstad, C Breuil
In vitro sporulation of selected wood decay fungi
1978 - IRG/WP 190
Basidiospores produced axenically without laborious attention in the laboratory are useful in studies of wood decay initiation. Such spores presumably approach those collected from natural sporophores in size and germinability (Morton, 1964). Production of spores in vitro by inversion of cultures grown on 2% malt extract agar in deep glass dishes (100x80 mm²) has been the preferred method (Morton...
E L Schmidt, D W French
Wood extractives as carbon sources for staining fungi in the sapwood of lodgepole pine and trembling aspen
1995 - IRG/WP 95-10098
Wood discoloration by sapstaining fungi reduces lumber value. In Canada, the most commonly recorded sapstaining fungi belong to the genera Ophiostoma. This work evaluated the effect that Ophiostoma piceae, Ophiostoma ainoae, and Ophiostoma piliferum used the lipids present in the sapwood of lodgepole pine (Pinus contorta Dougl.) and trembling aspen (Populus tremuloides Michx.). Wood lipids, common...
Yong Gao, C Breuil
Moisture requirements and wood degradation of pine and spruce wood by some Basidiomycetes-fungi
1989 - IRG/WP 1406
The minimum moisture requirements for the growth of the brown rot fungi, Coniophora puteana, Gloeophyllum trabeum and Serpula lacrymans were near or above the fibre saturation point of pine and spruce, sap and heartwood, during 160 days incubation according to the standard method EN 113. The moisture of wood for the optimum growth of Coniophora puteana and Serpula lacrymans was about 35-80% and fo...
H Viitanen, A-C Ritschkoff
Durability of Wood Plastic Composites Relative to Natural Weathering and Preservative Treatment With Zinc Borate
2005 - IRG/WP 05-40316
Wood-Plastic Composites (WPCs) used for decking have experienced dramatic increases in North America, averaging 25% growth per annum since 1998. A key factor contributing to this growth has been the successfully communicated message that they are "virtually maintenance free". The common perception being that the wood fiber is completely encapsulated by the thermoplastic resin, minimizing the pot...
M E Mankowski, F M Ascherl, M J Manning
Correlation between changes in colour and chemical composition during photo-degradation of wood surfaces
2005 - IRG/WP 05-40301
Changes in colour of wood (yellowing) during photo degradation or weathering reflect chemical changes in wood. Therefore, the relationship between changes in chemical composition and CIELAB colour parameters is very important to characterize photodegradation of lignocellulosic surfaces. In this study, the changes in chemical composition and yellowing due to photo-degradation was studied by expos...
K K Pandey
The possible role of mobile CCA components in preventing spore germination in checked surfaces, in treated wood exposed above ground
2001 - IRG/WP 01-30263
Untreated check surfaces are often exposed in CCA-treated lumber of refractory species used above ground since, during weathering, some checks develop beyond the preservative penetrated zone. However, decay is seldom observed in these checks even after many years of exposure. It is hypothesized that minor amounts of mobile CCA preservative components redistribute during weathering into checks, and...
S Choi, J N R Ruddick, P I Morris
Changes in pore structure and cell wall volume in wood decayed by brown- and white-rot fungi
1991 - IRG/WP 1501
Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (=Poria) placenta or Phanerochaete chrysosporium in soil-block cultures. Decay was terminated at various weight losses, and the pore volumes available to probes of various molecular weight and diameter were determined by the solute exclusion technique (Stone, J.E. and A.M. Scallan. 1968. Cellulose Chem. Technol. 2, 343-358.)....
D S Flournoy
The fungal degradation of quaternary ammonium compounds in wood
1998 - IRG/WP 98-10263
This work focuses on the biodegradation of didecyldimethylammonium chloride (DDAC) by the mould fungus Gliocladium roseum within a woody matrix. Three sawdust types, distinguished by their treatment and amount of DDAC retained, were inoculated with the fungus and their DDAC loss was measured over 11 weeks. The rates of degradation varied depending on the sawdust; however, a significant loss of DDA...
J W Dubois, J N R Ruddick
The degradation of wood surfaces by water
1984 - IRG/WP 3289
Thin radial/longitudinal sections (~100 µ) of Scots Pine (Pinus sylvestris) and lime (Tilia vulgaris), were exposed to deionised water over the temperature range 25-65°C. Losses in wet tensile strength and toughness occurred rapidly at temperatures from about 50°C upwards. After about 2 months' exposure pine lost some 10-30% of its tensile strength and 20-60% of its toughness. For lime...
W B Banks, P D Evans
An attempt to develop a direct and reliable method for testing the preventive action of preservation treatments of wood against fungal decay
1980 - IRG/WP 2139
In wood preservation there are two classical ways for assessing the reliability of preventive treatments against wood decay: the laboratory tests in which the various parameters are evaluated independently and the field tests or service tests in which those parameters are acting together in the natural environment. One has always tried to build bridges between the two types of experiments and to e...
M Fougerousse
Soft rot decay of Belian (Eusideroxylon zwageri) wood
1995 - IRG/WP 95-10119
The heartwood of Belian (Eusideroxylon zwageri), an East Malaysian timber species, is naturally durable due to its certain unique anatomical features and high content of extractives. The timber can tolerate years of exposure to hazardous conditions in ground contact and other situations without any significant loss in its strength. A few Belian transmission poles sampled from one locality in Saraw...
A H H Wong, A P Singh
Effect of fumigant residue in aerated wood blocks on the spore germination of decay fungi
1991 - IRG/WP 2382
Fumigants are increasingly used in several countries for remedial treatments of transmission poles to increase the service life. The present study was initiated primarily to test the remaining toxic effects of spruce (Picea rubra) wood, fumigated with chloropicrin (trichloronitro methane) or MIT (Methyl isothiocyanate) after long period of aeration, on the spore germination of decay fungi. This st...
J Bjurman, B Goodell
Decay resistance of Siberian larch wood against brown rot fungi - Part 2. The effect of genetic variation
1998 - IRG/WP 98-10287
Wood natural decay resistance is mainly restricted in the heartwood part of tree and based on wood microstructure and chemical composition. However, the variation of decay resistant in different wood species is vide and the effect of genotype on decay resistance of Siberian larch wood grown in Finland is not known. The aim of this work was to find out the variation on decay resistance of Siberian ...
H Viitanen, L Paajanen, T Nikkanen, P Velling
Long-term efficacy of wood dip-treated with multicomponent biocides
2005 - IRG/WP 05-30379
Biocides designed for prevention of indoor mold growth on wood-based materials need to provide long-term protection under conditions of high humidity. Specimens of kiln-dried southern pine and unseasoned southern pine, aspen, and Douglas-fir were dip-treated with borate-dimethylcocoamine (DMCA) supplemented with voriconazole, thiabendazole, or thujaplicin and evaluated at 4-week intervals for inhi...
C A Clausen, V W Yang
Creosote for wood preservation
1971 - IRG/WP 36
By creosote one usually means coal tar creosote, although there are creosotes of other origin. For example, wood tar creosote is a product of wood distillation. It is, in fact, in this connection that the word 'creosote' was first used. Early in the nineteenth century the oily product obtained by distilling wood was said to have an odour which resembled 'smoked meat&...
Anonymous
Determination of absorption, accumulation and transport of copper in mycelium of some wood decay fungi
1999 - IRG/WP 99-10323
Copper compounds are common wood preservatives. However, tolerance of some wood decay fungi to copper compounds has been observed recently. Therefore, we tried to elucidate possible causes of this phenomenon. We investigated uptake, accumulation and secretion of copper in the mycelium of potentially copper tolerant fungi (Antrodia sp.) and non tolerant fungus Trametes versicolor. We observed that ...
F Pohleven, S Breznikar, P Kalan, M Petric
The critical moisture and temperature conditions for the growth of some mould fungi and the brown rot fungus Coniophora puteana on wood
1988 - IRG/WP 1369
The growth of some mould fungi on pine and spruce sapwood was studied in 40 different constant moisture and temperature conditions. The temperature range was between +10 and +40°C and the relative humidities varied from 76 to 100% relative humidity (RH). The incubation time was 12 weeks. The mixed mould inoculation used included typical fungi growing on wood: Aspergillus versicolor, Cladosporium ...
H Viitanen, L Paajanen