Your search resulted in 1001 documents. Displaying 25 entries per page.
Influence of acidification on decay processes of CCB treated wood
2004 - IRG/WP 04-10514
The phenomenon of copper tolerance by brown rot fungal strains has been known for a long period but the complete mechanism of copper tolerance by these fungi is not understood yet. Copper tolerance has previously been linked to oxalic acid excreted by copper tolerant brown rot fungal strains. This acid reacts with copper in the wood to form an insoluble and therefore less toxic copper oxalate. The...
M Humar, S A Amartey, M Šentjurc, F Pohleven
Soil treatment tests with the three products of boric acid for the prevention of the hyphal growth of Serpula lacrymans
1992 - IRG/WP 92-3693
Laboratory soil treatment tests were conducted for the evaluation of fungicidal or fungistatic effect of boric acid products against Serpula lacrymans. Boric acid products tested were the following three: a thickened boric acid solution in triethanolamine, boric acid-silica gel complex granules, and a nonwoven fabric laminated with a polypropylene film and coated with boric acid granules on one si...
S Doi, A Yamada, Y Mineki, M Mori
The role of oxidation in wood degradation by brown-rot fung
1992 - IRG/WP 92-1562
Brown-rot fungi are suggested to degrade cellulose by oxidation with hydrogen radicalsformed eg. in the conversion of hydrogen peroxide in the Fenton type reactions. The stuctural changes in the holocellulose in wood induced by Fenton's reaction on wood components are very similar to those caused by brown-rot fungi. In this work the effect of the Fenton reaction on wood components was stu...
A-C Ritschkoff, J Pere, J Buchert, L Viikari
Alkaline building materials and controlled moisture conditions as causes for dry rot Serpula lacrymans growing only in houses
1985 - IRG/WP 1272
Dry rot Serpula lacrymans ( Fr.) S.F. Gray is commonly found in houses, though never with certainly in nature, like other wood destroying fungi which grow both indoors and outdoors. In investigating series of dry rot instances it was shown that this fungus is always found in covered places, close to a moisture source, the distance being from 0 a maximum of 600 cm. Owing to the dry rot has been abl...
J Bech-Andersen
A bioassay for appraising preservative protection of wood above ground
1978 - IRG/WP 2124
A bioassay, using the mold fungus Aspergillus niger, gave results that were correlated with amounts of pentachlorophenol and tributyltin oxide in pine sapwood treated with solutions ranging in strength from 0.016 or below to 5%. Limited bioassay estimates of penta in commercially treated millwork corresponded to estimates by lime ignition. The assay fungus exhibited somewhat greater tolerance of t...
T C Scheffer, L Gollob
Identification of brown rot fungi on wood in above ground conditions by PCR, T-RFLP and sequencing
2004 - IRG/WP 04-10512
Fungi selected in test fields in Germany and Estonia and fungi (Coniophora puteana) cultivated on medium have been identified by the molecular methods PCR (Polymerase Chain Reaction), T-RFLP (Terminal Restricted Fragment Length Polymorphism) and sequenced to species level. The samples from the German field test showed that the fruit body sample was a different fungus than from the mycelium sample....
U Råberg, N Högberg, C J Land
Relative merits of laboratory and field tests for assessing wood decay resistance
1993 - IRG/WP 93-20009
Laboratory and field trials have long been employed for assessing natural durability of a variety of wood species, but there is a continuing debate concerning the relative merits of approach. While laboratory tests provide carefully controlled conditions for decay, they are often criticized for being too artificial to produce meaningful results. Conversely, field trials often vary widely between t...
T C Scheffer, J J Morrell
Old and new facts on the dry rot fungus Serpula lacrymans
1991 - IRG/WP 1470
The article collates some of the recent literature on the biology of the dry rot fungus Serpula lacrymans. The fungus can grow at 28°C, and maximum wood moisture is above 55%. Serpula Iacrymans degrades crystalline cellulose. The intensive production of extracellular oxalic acid is neutralized by calcium and iron. There is considerable variation among the strains with regard to factors such as gr...
O Schmidt, U Moreth-Kebernik
Co-operative research project on L-joint testing. Sampling after 18 months exposure
1984 - IRG/WP 2233
In September 1983, Document No: IRG/WP/2208 was distributed giving guidance on sampling after 8 months exposure (due 1 December 1983 for those L-joints exposed on schedule on 1 April 1983), and including tables on which to record the test results. No major problems have been notified to Princes Risborough Laboratory concerning the sampling method. It is therefore proposed that the next sampling, a...
J K Carey, A F Bravery
Cytoplasmic and extracellular localization of manganese II dependent peroxidase(s) in white rot fungi during degradation of woody materials
1989 - IRG/WP 1416
The manner by which lignin is degraded in-situ in natural substrates by white rot fungi still remains a controversial issue particularly the distribution and role(s) played by lignin degrading enzymes (i.e. manganese II peroxidase and lignin peroxidase). In the present study, use was made of anti-manganese II peroxidase and immunolabelling techniques in conjunction with transmission electron micro...
G F Daniel, B Pettersson, T Nilsson, J Volc
Preliminary studies of the performance of iron chelators as inhibitors of brown rot (Coniophora puteana) attack
1996 - IRG/WP 96-10185
This paper describes experiments to examine the proposal that the presence of iron is essential for brown rot fungi to utilize hydroxyl radicals remote from the hyphae as a means of converting the wood into a food source. reliminary test results are presented from trials using three different iron chelators impregnated into Scots pine (Pinus sylvestris) sapwood blocks. Their relative effects on th...
E D Suttie, R J Orsler, P M Wood
Wood kiln drying. Simple process of material treament or soft method of preservation? (Le séchage arificiel du bois. Simple opération de traitement du metériau ou méthode douce de préservation?)
1993 - IRG/WP 93-50001-14
Among the processes enabling to extend wood durability, kiln drying can be considered as a treatment and soft preservation method. Dry woods are naturally durable provided they are not subject to important retaking of the moisture. Drying thanks to the application of temperatures from 50 to120°C enable to execute a thermic treatment which kills grubs and mushrooms to ensure a sterilization that c...
F More-Chevalier
Detection and estimation of Hylotrupes bajulus L. wood damages by ultrasonics
1990 - IRG/WP 2350
To evaluate the validity of the ultrasonic application in the detection and evaluation of wood damages produced by Hylotrupes bajulus L. larvae, some laboratory tests were made with small wood samples. The pulse through transmission method was used. The transit time of ultrasonic pulses in transversal sections, radial and tangential, of the samples was measured. The increment of the transit time o...
G Prieto
Interactions between water-borne preservatives and emulsion additives that influence the water repellency of wood
1991 - IRG/WP 2374
Incorporation of non-polar additives into water-borne treatments through of emulsion technology can greatly improve the physical characteristics of wood in service. Of specific interest with these emulsions is their effectiveness in reducing the rate of wood swelling. We have observed that the presence or absence of preservatives can often significantly influence the resultant effectiveness of the...
A R Zahora
A bioassay to determine preservative retention in hardwoods and southern pines
1982 - IRG/WP 2183
In this paper the author discusses and suggests a new method of evaluating preservative retention in treated woods by means of bioassays. Twelve North American species were tested with different retention levels of pentachlorophenol (PCP) and copper/chrome/arsenic (CCA) preservatives. The results observed in this work show that among other fungi, Aspergillus niger responds to both preservatives, w...
J C Moreschi
A test method to simulate above-ground exposure
1978 - IRG/WP 2112
The simulated above-ground exposure technique described is worthy of consideration as a simple procedure to determine the relative decay resistance of preservative-treated wood exposed to a moderate decay hazard. The method may readily be modified to allow testing of other materials such as plywood by simply enlarging the slots cut in the modified feeder strips. The method by no means completely s...
J A Butcher
Differences in pH, electrical resistance, cation composition and NIR spectra of red spruce wood during early stages of brown rot degradation
2002 - IRG/WP 02-10449
Red spruce sapwood was exposed to degradation by the brown rot fungi Coniophora puteana, Postia placenta, Gloeophyllum trabeum and Serpula lacrymans for 0, 1, 2 or 3 weeks using a modified soil block assay design. Average weight losses over time ranged from 0-8.9% during this time period. Detectable changes in pH, electrical resistance and cation compostion were observed in the wood as early as 1 ...
J Jellison, S Kelley, B Goodell, D Hui, A Ostrofsky
The need for realism in wood preservation research. A key address
1983 - IRG/WP 3254
The approval of a chemical for use as a timber preservative and the design of in service retention requirements represents an act linking fundamental research and commercial timber preservation. How difficult is it to translate figures generated through controlled experimentation into working specifications and how confident can we be in the methods used to provide such figures? The chairman of Wo...
L E Leightley
Preservation of wood-based panels against fungi and insects and and testing its efficiency
1976 - IRG/WP 270
Wood-based panel products which are made of susceptible wood species may be destroyed by fungi under wet conditions and by termites. The glues do not provide sufficient protection unless very high concentrations are applied. Particle boards and fibre boards are not susceptible to beetle infestation, although some species may attack plywood. Various types of preservatives provide sufficient protect...
G Becker, M Gersonde
Some aspects of testing water repellents
1998 - IRG/WP 98-40113
Several test methods are used to determine the efficiency of water repellent treatments on wood. The most common are: contact angle measurement, swelling rate of samples immersed under water and, the increase in mass of wood samples with time or after a fixed period of time either fully immersed under, or partially immersed in or floating on water.
In this paper, some fundamental aspects of the l...
D Lukowsky, M Farnow, T Rypstra
Proposals for further co-operative studies on determining toxic values against wood-destroying Basidiomycetes
1985 - IRG/WP 2237
Document IRC/WP/2194 reported the status of the programme of co-operative experiments up to and including December 1982. During discussions at IRG-13 in Turkey members endorsed the decision to complete the programme of tests and conduct repeat tests. At IRG-14 in Brisbane the report was noted but no further action agreed. At IRG-15 in Sweden a number of interested parties in the European/Scandinav...
A F Bravery
Leaching of active components from preservative-treated timber. Stages 2 & 3: Laboratory testing and comparison with semi-field testing
2004 - IRG/WP 04-20303
This part of the project is focussed on leaching from preservative-treated wood obtained by the laboratory test method CEN/OECD draft guideline, February 2003 ”OECD guideline for the testing of chemicals proposal for new guideline XXX. Estimation of Emissions from Preservative-treated Wood to the Environment: Laboratory Method for wood held in the storage yard after treatment and for wooden comm...
N Morsing, B Lindegaard
Synergistic combination of an antioxidant and wood preservative: a preliminary study
1998 - IRG/WP 98-30172
We previously proposed that extractives in highly durable angiosperm heartwood may protect wood against white-rot fungal colonization and subsequent degradation by a dual mechanism: extractives have some fungicidal activity and are also free radical scavengers (antioxidants) and thus interfere with the fungal free radical degradative mechanisms. We tested this hypothesis using the commercial bioci...
T Schultz, D D Nicholas, J Minn, K D McMurtrey, T H Fisher
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
Co-operative research project on L-joint testing. Progress report to March 1986
1986 - IRG/WP 2272
Further sets of data received from CTFT (France) after 18 months exposure, BAM (Germany) after 18 months exposure, STU (Sweden) after 9.5 months exposure and TI (Denmark) after 12 and 17.5 months exposure are presented and discussed in conjunction with data previously reported. The new data are generally in agreement with those presented previously and indicate the major difference between the co-...
J K Carey, A F Bravery