Your search resulted in 269 documents. Displaying 25 entries per page.
Toxic value estimation of wood preservatives by using the probit analysis
1990 - IRG/WP 2348
As it was assumed from previous experiments, the probit analysis appears to be the most suitable method of all used to estimate the toxic value of wood preservatives. With the help of the classical agar-block method the probit analysis was tested for its suitability in: 1) fungitoxic value estimation of the WR-3 preservative (quaternary ammonium compound + borate), as compared to different test fu...
J Wazny, K J Krajewski
New conception for shortering the duration of fungitoxic test of wood preservatives. Part 2: Computer-assisted miniaturisation of wood specimens
1994 - IRG/WP 94-20052
The mass loss of wood used as a criterion in the standarised agar-block method of evaluation of toxic value of preservatives depends upon the relationship between volume of specimens, their outspread planes and ratio of areas of particular anatomic sections. Upon the computer-assisted mathematical basis the dimensions of miniaturized specimens which make 1/2, 1/4, and 1/8 part of standarized ones ...
J Wazny, K J Krajewski
Evaluating the potential of amine chemicals for use as wood protecting agents. Part 1: Investigation of cation components of quaternary ammonium compounds
1994 - IRG/WP 94-30049
Quaternary ammonium compounds (quats) have shown a great potential as more environmentally acceptable wood preservatives. In order to identify chemicals possessing the wood protecting potential, an evaluation was carried out of a range of commercially available 'quats', using a modified soil block test. Ponderosa pine sapwood blocks were treated with selected 'quat&a...
Hang Tang, J N R Ruddick
The comparative resistance to fungi of the wood munika (Pinus heldreichii Christ.), fir (Abies alba Mill.) and spruce (Picea excelsa Poir.) compared with Pinus sylvestris L. and some physical and mechanical characteristics of munika
1981 - IRG/WP 1129
The munika (Pinus heldreichii Christ.) is situated primarily in the Balkans, and partially in the south of the Apenine peninsula. As an endemic species, with a very little annual increment, it has not been used enough as a timber for mechanical conversion up till now, although the oldest trees can grow to 27 m in height, with a diameter at breast height of about 60 cm. According to data of many Ba...
M Petrovic, M Miric
Targeted inhibition of wood decay (Using everything but the kitchen sink)
1997 - IRG/WP 97-10203
Low molecular weight oxidative decay agents have been implicated in the degradation of wood by brown-rot decay as evidenced by chemical analysis of brown-rotted wood and detection of oxalic acid and hydroxy radicals. Fenton chemistry (H2O2 / Fe++) is often proposed as the mechanism for generating hydroxy radicals. Previous authors have shown iron to enhance the brown-rot hydrolysis of wood, while ...
F Green III, T A Kuster, T L Highley
The biological effectiveness of wood modified with heptadecenylsuccinic anhydride against two brown rot fungi: Coniophora puteana and Gloeophyllum trabeum
1992 - IRG/WP 92-3705
A modified soil block test was carried out using wood samples reacted with heptadecenylsuccinic anhydride (ASA). This modification gave good resistance to decay brought about by the brown rot fungi Coniophora puteana and Gloeophyllum trabeum during the twelve week exposure period. Results indicated that there was a good correlation between increased loading of modifying reagent and an increase in ...
C Codd, W B Banks, J A Cornfield, G R Williams
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
Toxic values derived from EN 113 tests - are they determined by the virulence of a test fungus?
- Results from a round robin test -
1999 - IRG/WP 99-20176
The virulence of Coniophora puteana BAM Ebw. 15, the obligatory test fungus on softwood in tests according to EN 113, is known to be rather inconstant at least in some laboratories. The mass losses of untreated Scots pine sapwood blocks in an EN 113 test may range from below 20% to up to more than 50%. Possible reasons for these differences as well as the impact of a low virulence on the toxic val...
H Leithoff, R-D Peek, H V Borck, R Goettsche, H Kirk, M Grinda
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
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
Intraspecific variability of durability of Wapa courbaril (Eperua grandiflora) against Antrodia sp. and Coriolus versicolor: effect of radial and height position in the stem
2004 - IRG/WP 04-10531
The variation of a lesser-used species, Eperua grandiflora attacked by brown and white rot has been examined. Trees of this specie showed differences in their behaviour against the type of rot used and also showed evidence of intra and inter tree variation. The “tree” effect is very significant concerning natural resistance. In the same way, there is variation of durability observed according ...
N Amusant, J Beauchêne, M Fournier
The nature of osmiophilic particles and their distribution during different stages of brown and white rot decay
1983 - IRG/WP 1213
The distribution of osmiophilic particles during the course of brown and white rot decay was investigated by applying transmission electron microscopic (TEM) methods. It was found that it correlates with the brown and white rot pattern.The osmiophilic particles are produced by the fungus and are supposed to be wood rotting enzymes....
K Messner, H Stachelberger
Estimation of mycelial biomass by determination of the ergosterol content of wood decayed by Coniophora puteana and Fomes fomentarius
1989 - IRG/WP 1415
The mycelial biomass of fungi decomposing wood materials may be estimated by the use of an ergosterol assay technique.ln decay tests, essentially according to EN 113, estimates made by HPLC analyses on wood decayed by Coniophora puteana and Fomes fomentarius show the increase in biomass in the wood blocks. The ergosterol contents were correlated with dry weight loss determinations. Degradation of ...
K Nilsson, J Bjurman
Growth of the copper tolerant brown rot fungus Antrodia vaillantii on different substrates
1995 - IRG/WP 95-10121
In recent years the copper tolerant brown rot fungus Antrodia vaillantii caused severe damages on impregnated wood in ground contact. The pattern of decay gave the impression that impregnated wood was even more severely attacked than unimpregnated. To investigate this question more closely laboratory tests were carried out. In a "choice test" Antrodia vaillantii grew preferably towards CC-impregna...
H Leithoff, I Stephan, M-T Lenz, R-D Peek
The evaluation of a survey of dry rot damages in Japan
1983 - IRG/WP 1179
The damage of wooden houses from Serpula lacrymans has increased in Japan, particularly in the northern area, Hokkaido Prefecture (See Figure 1). The weather conditions in Asahikawa have been recorded. The data obtained from the survey carried out over the five years from 1975 to 1980 were previously reported to the 5th International Biodeterioration Symposium which was held in Aberdeen, Scotland ...
S Doi
Variations in the virulence of test strains of Coniophora puteana (Schum ex Fr) Karst
1982 - IRG/WP 2185
In laboratory experiments using petri-dishes and small wood blocks (30 x 10 x 5 mm³) 6 different isolates of Coniophora puteana strain BAM 15 were compared with strain FPRL 11E for growth rate and decay capability. Only the recently received strain from EMPA was suitably active giving 24% weight loss after 6 weeks compared with 38.1% for 11E. Collation of data from standard test records revealed ...
A F Bravery, J K Carey, W Worley
Use of compression strength loss for measuring decay in the soil block test
1996 - IRG/WP 96-20083
The possibility of using radial direction compression strength of wood, rather than mass loss, was evaluated for both a brown-rot fungus (Gloeophyllum trabeum) and white-rot fungus (Trametes versicolor). With untreated pine wafers (5 x 19 x 19 mm³ - l x r x t) exposed to Gloeophyllum trabeum in a soil block test for five days, the compression strength loss was nearly 50% compared to a 5% mass los...
D D Nicholas, Zhongwei Jin
Basidiospore structure and germination of Serpula lacrymans and Coniophora puteana
1988 - IRG/WP 1340
Using a nuclear staining technique and fluorescence microscopy, the basidiospores of Serpula lacrymans were shown to be uninucleate whereas those of Coniophora puteana were binucleate. The germination rate of the Serpula lacrymans spores, which was considerably lower than that of Coniophora puteana, decreased further after storage or heat treatment. Transmission electron micrographs indicate that ...
B M Hegarty, U Schmitt
Screening wood preservatives: Comparison of the soil block, agar block and agar plate tests
1993 - IRG/WP 93-20001
Several test procedures have been developed over the years to screen potential biocides for their value as wood preservatives. Each test has inherent advantages and disadvantages. In this paper the relative merits of the soil block, agar block and agar plate tests are compared. Eight commercially available biocides encompassing inorganic and organic systems were tested against four basidiomycete d...
K J Archer, D D Nicholas, T Schultz
Biological control of wood decay fungi. - Part II. Effects of exogenous nitrogen on effectiveness
2000 - IRG/WP 00-10360
The effects of nitrogen (urea and ammonium nitrate) on the ability of Trichoderma harzianum to inhibit the enzyme capabilities and decay capacities of Trametes versicolor and Gloeophyllum trabeum were investigated using a small wood sandwich decay test. The biocontrol fungus generally had a greater effect on the brown rot fungus, confirming previous reports. Nitrogen produced inconsistent effects ...
E A Canessa, J J Morrell
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
Bending properties of wood after its decay with Coniophora puteana and subsequent modification with selected chemicals
1999 - IRG/WP 99-40146
Mechanical properties of wood are often decreased due to decay processes caused by biotic and/or abiotic factors. Damaged wooden elements (e.g. historical structures) can be reinforced by more methods, including their modification with convenient chemicals. This paper presents influences of selected chemicals on basic bending properties (modulus of elasticity - MOE, modulus of rupture - MOR) of so...
L Reinprecht, S Varinska
Development of a mini-block test method for the rapid evaluation of preservative performance against Basidiomycte fungi
1991 - IRG/WP 2379
Screening procedures for new biocides used as wood preservatives can be a time consuming process using conventional Basidiomycete assay procedures. This is due mainly to the long exposure periods required to achieve adequate levels of decay (weight loss) in the test blocks. A number of alternative methods have been developed but most utilise artificial substrates such as filter paper or agar in wh...
J Brown, S Caswell, G R Williams
The preventive effectiveness of preservative treatments against wood-rotting fungi. Preliminary results
1992 - IRG/WP 92-2407
The efficacy of a range of preservative treatments in preventing colonisation by decay fungi has been assessed using a method developed at BRE and similar to that adopted by Working Group 9 of European Standards Committee CEN/TC 38. Assessment was made using baits inserted into the test blocks, in holes which had been drilled after treatment to within defined distances of the treated face exposed ...
J K Carey