Your search resulted in 3495 documents. Displaying 25 entries per page.
Modification of solid wood: research and practical potential
1997 - IRG/WP 97-40098
The polymeric structure of the wooden cellwall mainly consists cellulose, hemicellulose and lignin. The most reactive sites on these components are the hydroxyl groups. The cellwall polymers (and its reactive hydroxyl groups) are responsible for most physical and chemical properties of wood. By changing the basic chemistry of the cellwall polymers, it is possible to change different undesirable at...
H Militz, E P J Beckers, W J Homan
Modelling of copper emission fron treated wood leached according to NEN 7345 and ENV 1250.2
1996 - IRG/WP 96-20097
A series of water leaching experiments is carried out investigating pine and spruce treated and fixed using different copper-containing preservative solutions and process technologies. Water changes took place as prescribed in the Dutch standard NEN 7345 and the European test method ENV 1250.2, each of the leachates being chemically analysed for their copper content. Irrespective of the preservati...
G M F Van Eetvelde, S G L Michon, M Stevens
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
Categories in wood preservation hazard, risk, and use
1994 - IRG/WP 94-20048
In various countries hazard-, risk-, or use-categories have been established. The different terms seem to be only a sophisticated language problem, but they are rather a basic principle of the philosophy of wood preservation which is going to obtain importance with respect to the low reputation of chemical wood preservatives in an increasing number of countries. Whilst hazard signifies the fact th...
H Willeitner
Dimensational stabilisation of wood
1981 - IRG/WP 3171
A review is given of the studies on the dimensional stabilisation of wood which have been carried out in the laboratory 5.14 "Wood Technology" since 1967. All stabilisation methods known have first been compiled from the available literature. Practical studies were then started. Wood was treated with monomers (styrene, methyl metacrylate, isocyanate), formaldehyde, tannin and sugar. Despite a sati...
A Burmester
Three years of field tests with "Lignomer" stakes in ground contact
1981 - IRG/WP 3166
The "Lignomer" (Wood Polymer Composite) is a material obtained during the polymerisation of various monomers or its mixtures in wood. As laboratory tests have shown, this material is characterized by a high resistance against biological deteriorating agents. The laboratory investigations on the durability of various materials against biological deterioration are in many instances extended by field...
K Lutomski
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
Laboratory versus field tests for evaluating wood preservatives: A scientific view
1995 - IRG/WP 95-20076
The relative merits of field tests versus laboratory tests for evaluating wood preservatives are discussed. Many of the problems involved in interpretation of the results are similar for both types of test. One major problem is to select field sites or laboratory tests that are representative for the practical use of treated timber in ground contact. Decay tests with treated wood in unsterile soil...
T Nilsson, M-L Edlund
Northern oak wood and its damages in Iran
1988 - IRG/WP 1377
The Northern oak species of Iran designated Quercus castaneaefolia C.A.M. is distributed widely in caspian littoral. In natural conditions (healthy) has favourable quality and it is used mostly in rural construtions, sleepers, parquets, cross arms for electric and communication poles, it is used also indoor and window construction, benches and finally veneer. This wood in the case of sleepers and ...
D Parsapajouh, P Niloufari
A comparative analysis of Coniophora olivacea (Fr. ex Pers.) Karst. and Coniophora puteana (Schum. ex Fr.) Karst. test strains
1993 - IRG/WP 93-20004
Investigations were carried out to compare pure cultures of Coniophora olivacea (Fr. ex Pers.) Karst. used as a test fungus in Australia and other Pacific countries, and Coniophora puteana (Shum. ex Fr.) Karst. which is used in Europe. Comparisons included morphology, growth rate and dry mass of mycelium, decay capacity, influence of temperature, toxic value of CCA and quaternary ammonium compound...
J Wazny, L J Cookson
Performance criteria for approving new wood preservatives for ground contact
1994 - IRG/WP 94-20021
Protocols for testing novel formulations prior to approval or registration as wood preservatives are being developed in a number of countries, e.g. Australia, New Zealand, USA. One aspect which must be addressed is the effectiveness in tests relative to that of currently approved formulations which would be acceptable to approving authorities. It is assumed that natural exposure testing is a prere...
M E Hedley
Tropical In-Ground Durability of Structural Sarawak Hardwoods Impregnated to High Retention with CCA-salts, CCA-oxide and FCAP after 20 Years Exposure
2005 - IRG/WP 05-30384
Statistical analysis (ANOVA) was conducted on durability (termite and decay combined) rating data collected over 20 years exposure period of over 140 species of Sarawak timbers with altogether 30,000 stake specimens, at the Forest Department’s Sibu “graveyard” stake test sites from 1977. About 20 replicated stakes were pressure-treated to refusal with 10% g/ml concentration of up to 3 CCA-sa...
Wang Choon Ling, A H H Wong
Enhanced removal of CCA from treated wood by Bacillus licheniformis in continuous culture
1997 - IRG/WP 97-50083
A gram positive, spore-forming bacterium, which was isolated from a 20-year-old Forest Service test plot of CCA-treated 2 x 4's in Madison, WI., demonstrated the ability to release copper, chromium, and arsenic from CCA-treated wood in liquid culture. CCA-treated sawdust was exposed to this organism, which has been presumptively identified as Bacillus licheniformis. Analysis of the sawdus...
C A Clausen
Variation in biological performance of CCA caised by preservative application method
1996 - IRG/WP 96-40072
A series of laboratory studies to investigate the influence of treatment application method on CCA performance in Cosican pine has been completed. Biological decay tests, such as serial exposures, were used to induce decay in wood at preservative retentions of up to 10 kg/m³ CCA salts. Significant differences in performance of the preservative against either brown, white or soft rot decay fungi w...
P R Newman, R J Murphy
Pollution in wood preservation - Aspects and problems
1973 - IRG/WP 55
In the field of wood preservation too, pollution problems have to be considered. They originate with the wood preservatives used. The extent of pollution differs widely with the type of preservative and the treatment process used. Per unit of impregnated timber, pollution will be lower if treatment is performed in treating plants than in distributed places. It will be highest for the old type Bouc...
H Willeitner
Preservatives stains as exterior wood finishes
1977 - IRG/WP 389
For many years wood preservatives and paints have been used as the only treatment for exposed wood surfaces. Because of the inherent color of the preservatives, such as creosote, the wood surface was stained as well as protected from attack by micro-organisms. Paints protect surfaces from weathering, but recently, with an increased interest in maintaining the more natural appearance of exterior wo...
D W French
Isolation and identification of the fungal flora in treated wood. Revised technique
1977 - IRG/WP 159
At the 8th Annual Meeting in Wildhaus a paper was presented for discussion on the isolation of fungi from treated wood.·Since then work of this nature has been undertaken at Imperial College and as a result a revision of that document has been made and is presented here. The main alterations are: 1) To streamline the isolation procedure 2) Modification of the benomyl agar 3) The inclusion of a st...
C P Clubbe, J F Levy
The role of mechanised harvesters in the dissemination of fungal inoculum into radiata pine logs in New Zealand
2002 - IRG/WP 02-10426
A joint research programme has been initiated between Forest Research, New Zealand and Forintek Canada Corp., Canada, to determine the role of mechanical tree harvesters on disseminating fungal inoculum into logs. Mechanical harvesters cause loosening and removal of bark and also damage the surface of the wood with their feed rollers leaving indentations up to several centimetres deep. Results ...
D O’Callahan, B Kreber, A Uzunovic
Decay potential of various New Zealand Phlebiopsis gigantea strains using a soil block method
1999 - IRG/WP 99-10309
The objective of the current study was to determine the decay potential of different strains of Phlebiopsis gigantea using Pinus radiata and European Fagus sylvatica, respectively. A soil block method was used to determine mass weight loss of P. radiata and F. sylvatica following 10 weeks incubation with different strains of P. gigantea. For comparison, Trametes versicolor, Postia placenta, Gloeop...
B Kreber, J G Van der Waals
Cavitation bacteria
1984 - IRG/WP 1235
A form of bacterial wood degradation is described. The term "cavitation bacteria" has been coined in order to describe the discrete cavities that are formed within the wood cell walls. The bacteria observed within the cavities appeared to be polymorphic with rounded as well as filamentous forms recognised. TEM studies suggest that the bacteria produce diffusable wood-degrading enzymes. Cavitation ...
T Nilsson, A P Singh
Towards a unified international hazard class system
1996 - IRG/WP 96-20081
Working party 2.5 on International Standardisation has set the development of a unified hazard class system as a short-term objective. This document is intended to stimulate the discussion required to work towards such a system. Two possible approaches are discussed, the compromise approach and the development of a basic system from first principles. For the second approach, the factors impacting ...
P I Morris
Exterior wood stains
1979 - IRG/WP 3136
The use of semi-transparent exterior wood stains has grown remarkably since their development during the 1960s. This can be partly attributed to their offering a break with tradition at a time when it was being recognised that changes in the quality of timber and how it was used demanded different methods of exterior wood finishing. Information is already available on the characteristics and uses ...
E R Miller
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
Effects of steaming heat treatment of wood on the stimulation of termite feeding
1997 - IRG/WP 97-10212
At the 26th IRG conference, we reported that steamed Japanese larch heartwood samples were suffered a serious attack by subterranean termite, Coptotermes formosanus both in choice and no-choice feeding tests. This is possibly caused by the yield of termites stimulants in the wood samples resulting from the steaming process. Since the steaming heat treatment has often been applied to other several ...
S Doi, Y Kurimoto, M Takahashi, T Yoshimura
Ten year performance of l-joints made from borate diffusion treated wood
2000 - IRG/WP 00-30225
While there are decades of experience with borate-treated wood in coated, exterior applications in New Zealand and the UK, other countries have been more reluctant to use this process. As part of a research program on the potential use of borates by the Canadian wood products industry, Forintek set up, in 1990, an L-joint test of untreated and borate-diffusion treated hem-fir (western hemlock and ...
P I Morris