Your search resulted in 456 documents. Displaying 25 entries per page.
Imaging fungal deterioration of wood using x-ray microtomography
1997 - IRG/WP 97-10240
Nondestructive tomographic images of solid Southern yellow pine (SYP) wood and SYP during deterioration by wood decay fungi were obtained by using a new class of synchrotron X-ray computed microtomography (CMT). The CMT images will provide information about spatial relationship between degrading fungi and wood structures. Wood samples were scanned with synchrotron-generated X-rays at high resoluti...
B Illman, B A Dowd
The relationship between preservative type and surface degrade in Pinus radiata
1980 - IRG/WP 3158
Samples of Pinus radiata D. Don were impregnated with one of two preservative types, a copper chrome arsenic salt and a light organic solvent preservative. The panels were exposed to the weather for 4-5 years at a site near Sydney, Australia. Macroscopic and microscopic examinations showed different rates and patterns of weathering between the samples treated with each preservative and an untreate...
R S Johnstone, R K Bamber
The involvement of extracellular substances for the generation of hydroxyl radical during wood degradation by white-rot fungi
1997 - IRG/WP 97-10218
The activities of one-electron oxidation, hydroxyl radical generation, and phenol oxidase during the incubation of cultures of four white-rot fungi containing either glucose or wood were periodically measured. Further, their degradation activities against wood were examined during the course of cultivation. The generation of hydroxyl radical was correlated to the activity of wood degradation and i...
H Tanaka, S Itakura, A Enoki
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
Micromorphology of oak wood degraded by brown rot fungus Coniophora puteana
2000 - IRG/WP 00-10356
To characterize the degradation of hardwood by brown rot fungus, Coniophora puteana was incubated on the wood blocks of Quercus accutissima. For comparison, the same fungus was also incubated on the pine wood blocks of Pinus densiflora. In softwood, the shape of the wood cells and thickness of the cell appeared unchanged even the loss of birefringence in the affected areas. In contrast, oak wood d...
Yoon Soo Kim, Seung-Gon Wi, Kwang-Ho Lee
Fungal decay resistance of Rubber wood treated with heartwood extract of Rosewood
2005 - IRG/WP 05-30367
Alcoholic extract of Dalbergia latifolia heartwood was studied for its toxicity towards wood decaying fungi. Rubber wood blocks were treated with this extract to three different retention levels (0.1%, 0.2% & 0.5%) and the treated wood blocks were assessed for their resistance towards two white rot and two brown rot fungi. Treated blocks showed improved resistance over the control blocks. At 0...
A K Sethy, H C Nagaveni, S Mohan, K T Chandrashekar
Persistence and residual activity of organophosphorus termiticides in soil and prevention against the degradation of chlorpyrifos
1991 - IRG/WP 1518
The persistence and the residual activity of four comercial organophosphorous termiticides, Chlorpyrifos, Fenitrothion, Tetrachlorvinphos, Pyridaphenthion, in soil were studied under laboratory conditions. The persistence and the residual activity of four organophosphorous termiticides in two types of soil decreased with the lapse of time. These termiticides were mostly degraded by microorganisms ...
T Iijima, M Tanaka, M Higaki
Anti-fungal properties of pyrolytic oils derived from softwood bark
2000 - IRG/WP 00-30218
Thermal decomposition of balsam fir and white spruce mixed bark residues at 450°C and under vacuum (< 20 kPa abs.) results in high yields of pyroligneous liquors rich in phenolic content. This vacuum pyrolysis process has been scaled-up to a pyrolysis plant with a feed capacity of 3.5 t/h of softwood bark, which is the largest plant of this type in the world. The pyrolytic aqueous condensates ...
D Mourant, Dian-Qing Yang, Xiao Lu, C Roy
Evaluation of white-rot fungal growth on Southern Yellow pine wood chips pretreated with blue-stain fungi
2000 - IRG/WP 00-10349
White-rotting basidiomycetes do not colonize on southern yellow pine. This study seeks to reduce the resinous extractive content of southern yellow pine by treating it with blue stain fungi. The mycelial growth of wood-inhabiting ligninolytic white-rot fungi can be achieved on pretreated southern yellow pine wood. Aureobasidium, Ceratocystis, and Ophiostoma spp. removed 70% to 100% of the extracti...
S C Croan
Fungal decay of acrylate treated wood
2004 - IRG/WP 04-30357
Natural durability of wood species is variable. Chemical wood preservatives, such as biocides are necessary for extension of their service life. Many methods have been developed to increase the resistance of wood and wood products against wood-destroying organisms during the last years. The most frequently used methods are chemical and thermal modification of wood. In wood modification the basic c...
Z Tiralova, L Reinprecht
In situ testing the influence of melamine resins on the enzymatic activity of basidiomycetes
1999 - IRG/WP 99-30194
Waterbased methanol etherificated melamine formaldehyde resins have the potential to increase the resistance of impregnated wood against wood destroying fungi. The mechanism of the increased wood durability is not clear yet. In the present paper the possible interference of melamine resins with wood degrading enzymes of Coniophora puteana and Trametes versicolor was investigated as a possible cont...
D Lukowsky, F Büschelberger, O Schmidt
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
Biological degradation resistance of wood acetylated with thioacetic acid
1983 - IRG/WP 3223
Chemically, modification of wood is being considered as an alternative to conventional preservation by toxic chemicals. Acetylated wood has been reported to be quite resistant to most biodegrading organisms at weight percent gains (WPG) around 15-19. The conventional acetylation techniques with acethic anhyrdride result in generation of acetic acid. However, acetylation with thioacetic acid overco...
S Kumar, S C Agarwal
Physiological properties of fungal test strains according to the European Standard EN 113
1986 - IRG/WP 2258
For the discussion of the European standard EN 113 the EMPA's procedure of culturing the test fungi and the corresponding virulence of the test fungi as well as the wood moisture content at the end of the test are shown. It is mainly shown that within the standard the choice of the solvent may not be left at the test lab if reproducible results shall be obtained. The different solvents in...
E Graf, B Zgraggen, P Manser
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
The role of chitinase in bioprotectant activity against staining fungi
1996 - IRG/WP 96-10175
Chitin is an important structural component of the hyphae of many wood staining fungi and its disruption can lead to dramatic declines in their growth. A number of bioprotectants have been shown to produce chitinases in liquid cultures, but the role of these enzymes in bioprotection remains poorly understood. The levels of these enzymes was studied by inoculating ponderosa pine sapwood wafers with...
J Liu, J J Morrell
A comparison of fungal strains used in the bioassay of wood preservatives
1984 - IRG/WP 2220
Previously published data are presented relating to a number of strains of wood-destroying basidiomycetes (Coniophora puteana, Coriolus versicolor, Gloeophyllum abietinum, Gloeophyllum sepiarium, Gloeophyllum trabeum, Lentinus lepideus, Poria placenta, Fibroporia vaillantii and Serpula lacrymans) commonly used as test fungi in the bioassay of wood preservatives. The data, which has not been statis...
J Wazny, H Greaves
Chemical and biological investigations of double-vacuum treated windows after 7½ years in service
1985 - IRG/WP 3339
Earlier investigations of double-vacuum treated windows after five years in service have shown that tributyltin oxide (TBTO) degrades to di- and monobutyltin compounds and that the resistance of the wood against decay decreases. An investigation 2.5 years later of the same windows shows that the degradation of TBTO proceeds fast. After 7.5 years in service only 15-35% of the remaining organotin co...
M-L Edlund, J Jermer, B Henningsson, W Hintze
The influence of fungal species and the level of decay on the mortality and feeding activity of adult Euophryum confine (Broun)
2002 - IRG/WP 02-10448
The mortality and feeding activity of adult Euophryum confine (Broun) (Coleoptera: Curculionidae) are used to establish the substrate conditions most suitable for their rearing. Weevils were allowed to feed on Pinus nigra (Arnold) sapwood blocks, either undecayed or
decayed to 10% weight loss ±5% by two brown rots Coniophora puteana (Schum.:Fr.) Karst. and Serpula lacrymans (Wulf.:Fr.) Schroeter...
M Green, A J Pitman
Microscopic FT-IR depth profiling study of photo-induced degradation in wood
2001 - IRG/WP 01-20229
FT-IR microspectroscopy was used to monitor the changes in the chemical composition at various depths from the photo-irradiated surface of sugi (Cryptomeria japonica D. Don) sapwood. The radially cut wood face was exposed to artificial solar radiation from a xenon light source at 375 Wm-2 (in a 300 - 700 nm spectral range) for up to 600 h. The IR depth profiling spectra showed that the artificial ...
Y Kataoka, M Kiguchi.
Bacterial degradation of wood cell wall: A review of degradation patterns
1990 - IRG/WP 1460
Information from bacterial degradation studies of 60's and 70's was reviewed by Nilsson in 1982. The application of electron microscopy to this area in recent years has provided much useful information and has eliminated earlier scepticism among workers about the ability of bacteria to degrade lignified wood cell walls. Studies using transmission electron microscopy together with...
A P Singh, J A Butcher
Preliminary evaluation of new quaternary ammonia compound, didecyl dimethyl ammonium tetrafluoroborate for preventing fungal decay and termite attack
2005 - IRG/WP 05-30375
This study evaluates the decay and termite resistance of wood treated with didecyl dimethyl ammonium tetrafluoroborate (DBF), a recently developed quaternary ammonia compound containing boron. DBF contains boric tetrafluoride as a counter ion in its chemical structure. Laboratory decay resistance tests were performed using brown-rot fungus, Fomitopsis palustris and white-rot fungus, Trametes versi...
S N Kartal, W J Hwang, Y Imamura
A technique for determining the efficacy of water diffusible preservative plugs for implanting in joinery in service
1987 - IRG/WP 2291
A technique is described for determining the efficacy of soluble, diffusible preservative plugs for eradicating decay in joinery. It uses blocks of Scots pine sapwood or heartwood adjusted to known moisture contents prior to the establishment of the test fungus Coniophora puteana, from a single longitudinal dowel and the subsequent introduction of the preservative plugs. Prevention of decay, eradi...
J K Carey, A F Bravery
The degradation of wood surfaces by dilute acids
1985 - IRG/WP 3326
Thin radial/longitudinal sections(~100 µ) of Corsican Pine (Pinus nigra) and Lime (Tilia vulgaris), were exposed to Sulphuric, Sulphurous, nitric, acetic, and formic acid at 40°C in the pH range 2-6. After about 3 months exposure to Sulphuric, nitric, acetic and formic acid at pH 2.0 Pine lost some 20-25% of its tensile strength. Losses in tensile strength due to sulphurous acid were greater bei...
P D Evans, W B Banks