Your search resulted in 191 documents. Displaying 25 entries per page.
The accelerated L-joint test method for determination of the out of ground natural durability
1998 - IRG/WP 98-20146
The accelerated L-joint test incorporates a moistening device and uses a close end water trap in an open joint connection with a laminated tenon member consisting of the perishable reference wood species scots pine sapwood and beech.
After one year of exposure it is possible to show a distinct identification of natural durability classes 4 and 5 against the more durable wood species. Both weight ...
J Van Acker, C Brauwers, M Stevens
Assessing health risks to occupants following remedial insecticidal treatment of timber in dwellings
1998 - IRG/WP 98-50101-27
Experiments have been carried out to assess (i) the aerial concentrations of volatile wood preservative constituents, and (ii) the potential for contamination from treated surfaces, following in situ insecticidal treatment of timbers in dwellings. Using white spirit as a model for volatile constituents in the treatment of free-standing, wood-lined chambers indicated that temperature and air exchan...
R J Orsler, E D Suttie, V Rijckaert
Development of threshold values for boron compounds in above ground exposures: Preliminary trials
1998 - IRG/WP 98-30179
Boron is increasingly used both as an initial and remedial treatment for protecting wood against fungal and insect attack. While establishing lethal dosages for boron against insects through feeding tests is relatively simple, establishing thresholds for fungal attack poses more of a challenge. Tests using boron dispersed in agar artificially surround the fungus with both boron and excess nutrient...
J J Morrell, C M Freitag, S Unger
Eradication of wood decay fungi by means of radio frequency
1998 - IRG/WP 98-10292
High frequency electromagnetic fields i.e. radio frequency (RF) are used in wood industry for heating, gluing and bending of wood and are also appropriate for eradicating of wood decay fungi and insects. We investigated the effects of RF exposure on wood samples which were in vitro infected by Coniophora puteana, Gloeophyllum trabeum and Lentinus lepideus. For each fungus, the lethal temperature a...
F Pohleven, J Resnik, A Kobe
An alternative method for the determination of lignocellulolytic enzymatic activities of white rot fungi
1998 - IRG/WP 98-10261
Some lignocellulolytic activities of wood decay fungi can be evaluated in an indirect way through the study of the decolorization that white rot fungi produces in culture media in the presence of dyes.
In this assay, ten dyes were selected, which were added in concentrations of 0.00 1% - 0.003% (P/V) to four-day cultures of Trametes versicolor containing 1% of beech sawdust in a basal salt medium...
D Muñoz-Mingarro, F Llinares, F Rubio, M Yuste, C Rodríguez-Borrajo, J Jiménez, M T De Troya
The content and mobility of copper, chromium and arsenic in the soil of a wood preserving plant using CCA
1998 - IRG/WP 98-50122
Analyses were carried out on soil and water samples obtained from a wood preserving plant using CCA-type preservatives. The plant has been in operation since 1969. The soil samples were obtained on 8 points from 4 different depths. The estimation of the type of soil was followed by investigations of copper, chromium and arsenic contents, and the mobility of these elements. The soil samples were al...
N Erdin, S N Kartal, A Dilek Dogu, M O Engür
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
Immunoassays for detecting and tracking wood-protecting chemicals
1998 - IRG/WP 98-50101-10
To respond to new environmental regulations, forest products industries are reducing or eliminating the release into the environment of chemicals used to protect wood products. For this, mills need tools that support practical and reliable programs for monitoring concentrations of wood protectants in processes and the environment. Conventionally, wood preservatives are detected mainly by gas-liqui...
C Breuil, J Bull
Occupational exposure risk assessment at a commercial treatment plant using copper azole preservative
1998 - IRG/WP 98-50101-15
Experience with traditional water-based preservatives such as chromated copper arsenate (CCA) applied in closed system vacuum pressure impregnation plants has shown that operator atmospheric exposure is low during normal operation.
TANALITH E is a commercially available copper azole wood preservative introduced as a chrome and arsenic-free alternative to CCA based on the actives copper, tebuconaz...
A S Hughes, M Connell
Method of embedding and staining of wood after biological testing to support the identification of decay type
1998 - IRG/WP 98-20131
A method for preparing wood for microscopic analysis after decay testing is described, with special regard to a novel fast simultaneous staining, which helps to identify different types of decay. The novel staining process is explained as well as the embedding of heavily decayed samples in polyethylene glycol (PEG) and picking up of sections by transparent adhesive tape. Special feature of the int...
A O Rapp
The kinetics of anhydride modification reactions of wood. Experimental results and theoretical modelling
1998 - IRG/WP 98-40125
Although the chemical modification of wood remains a fertile area for research, there has been little work performed on the kinetics of the modification process. The reaction kinetics of a series of linear chain and cyclic anhydrides has been studied and activation energies of the reaction determined. The reaction kinetic profiles are determined by the relative rates of reaction of the reagent wit...
C A S Hill, J G Hillier
Genetic Engineering in tree breeding
1998 - IRG/WP 98-10294
The genetic improvement of forest trees by classical breeding is a slow process in comparison with that of annual crops. Tree breeding however is of great importance and has led to trees with better growth characteristics and better disease resistance. An important wood characteristic which has been neglected in breeding programs is wood durability. The durability of the wood will determine for wh...
J Van Doorsselaere, H Beeckman, M Van Montagu, W Boerjan
Glued laminated poles - Progress report after 18 years' testing
1998 - IRG/WP 98-20140
In 1979 a number of glued laminated poles treated with CCA and creosote were placed in a greenhouse at Uppsala, at the Simlångsdalen test field in southern Sweden and under a power line in Vuollerim in northern Sweden in order to study their resistance against biological degradation.
The tests have shown that the best performance will be obtained if each laminate is first treated with a water-bo...
Ö Bergman, J Jermer
Effect of post-treatment processing on leachability of ACZA-treated douglas-fir lumber
1998 - IRG/WP 98-50109
The effect of post-treatment procedures that more rapidly precipitate copper, zinc, and arsenic in douglas-fir treated with ammoniacal copper zinc arsenate (ACZA) on subsequent leaching resistance were investigated at two retentions (6.4 and 40 kg/m3). Total leaching was greater from boards treated to the higher retention. At both levels, copper was lost at the highest rate. Post-treatment process...
J J Morrell, C S Love, S Kumar, C M Freitag
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
In vivo growth study on two gymnosperms and four angiosperms for REB wood poles
1998 - IRG/WP 98-10246
Revealed that the highest growth rates and pole yield in two plantation sites in Bangladesh are significant with 2.06 cm/y in diameter, 0.97 m/y in height and 90% pole yield within 19y in Pinus caribaea; 1.96 cm/y, 0.91 m/y and 100% pole yield within 15y in Xylia dolabriformis; 1.88 cm/y, 0.91 m/y and 22% pole yield within 13y in Dipterocarpus turbinatus; 1.64 cm/y, 0.82 m/y and 28.75% pole within...
A K Lahiry
Proposal for a method aiming at the quantification of the impact of wood extraction in Life Cycle Assessment
1998 - IRG/WP 98-50113
Life Cycle Assessment has been accepted as an instrument for the assessment of the environmental impact of products. Characterisation factors for impact assessment of emissions from products have been established. To date no characterisation factor exists for the extraction of biotic resources, for example wood. Since the main disadvantage of using wood as a material lies in the extraction of reso...
P Esser, E Van der Voet
International standardisation: a hypothetical case study with stand-alone borate wood preservatives
1998 - IRG/WP 98-20147
The possibility of developing wood preservation standards with a global remit has a number of obvious advantages as well as far reaching ramifications, many of which are undefined as yet. The commercial implications of adopting international standards are clearly considerable, but equally, such a development is likely to focus attention on the conceptual differences in the way that different regio...
M W Schoeman, J D Lloyd
Uptake of copper by mycelium of wood decay fungi growing on copper S-substituted thioglycolate containing nutrient media
1998 - IRG/WP 98-10291
Mycelia of Trametes versicolor, Coniophora puteana and Poria monticola were grown on potato dextrose agar (PDA) media, containing various concentrations of copper N,N-dimethyldithiocarbamoylacetate (which may be regarded as a copper S-substituted thioglycolate). The tested copper compound revealed relatively low fungicidal activity. After 13-18 day growing period, we determined concentrations of a...
M Humar, M Petric, F Pohleven, P Kalan
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 4. MPP compared with other processes for achieving acceptable treatment of radiata pine heartwood
1998 - IRG/WP 98-40115
Although radiata pine sapwood is very amenable to preservative treatment, it is often difficult to achieve the required standard for heartwood treatment.
A preliminary investigation showed that to achieve the NZ Timber Preservation Council minimum penetration requirements for radiata pine heartwood using the Multiple-Phase Pressure (MPP) Process, a hydraulic pressure of at least 1250 kPa for 20 m...
K Nasheri, J A Drysdale, G Durbin, M E Hedley
Screening of fungal strains for wood extractive degradation
1998 - IRG/WP 98-10254
Fungal strains were screened for their ability to degrade apolar extractives in wood from scots pine. The degradation of total wood extractives by 91 different strains was monitored in stationary batch assays incubated for 6 weeks. The results obtained show that the ability of wood-inhabiting fungi to utilize wood extractives varied greatly, even for different isolates of the same species. Fungal ...
J Dorado, M J Martinez-Inigo, T A van Beek, F W Claassen, J B P A Wijnberg, R Sierra-Alvarez
Utilisation of carbohydrates by stain fungi in agar culture
1998 - IRG/WP 98-10248
Stain fungi are often defined by their ability to utilise the starch and free sugars found in ray parenchyma cells, and their inability to utilise other wood constituents. However, several species of stain fungi produce bore holes in wood cell walls. This suggests that enzymatic activity capable of degrading structural polysaccharides and/or lignin is associated with the growth of the appressorium...
J Snow, P Vinden, S M Read
Recycling of CCA treated wood in the US
1998 - IRG/WP 98-50101-08
The production of CCA treated wood has increased dramatically in recent years. Previous estimates of the volume of treated wood to be removed were based on the assumed service life of the material, generally 20 to 25 years. This study based on a survey of contractors installing treated decks, determined that the actual service life of these decks is much shorter than their assumed functional servi...
J McQueen, J Stevens, D P Kamdem
Aquatic toxicity research of structural materials
1998 - IRG/WP 98-50114
Continuing from preliminary results reported on the aquatic toxicity of some tropical hardwoods under high hazard conditions, a more comprehensive research study is set-up in order to assess the environmental toxicology of various structural materials in water applications. Hazard class 4 preservative treated wood is tested for its toxic response on a battery of aquatic test organisms, next to con...
G M F Van Eetvelde, S De Geyter, P Marchal, M Stevens
Leaching of components from CCF treated timber in ground contact
1998 - IRG/WP 98-50108
In order to investigate the depletion of different CCF-salts during service small stakes (10*10*450mm³) were treated with five water-borne wood preservatives and after fixation brought into ground contact for several years. After failing some of the broken down stakes were used to determine the remaining concentration of relevant ions and their distribution in different segments of the stakes.
A...
E Melcher