Your search resulted in 242 documents. Displaying 25 entries per page.
Environmentally benign wood preservatives based on organic biocide antioxidant combinations: A brief review of laboratory and field exposure results and discussion of a proposed mechanism
2004 - IRG/WP 04-30335
The combination of various organic biocides with commercial antioxidants generally increased the biocides’ efficacy 2-3 fold against wood-destroying fungi in short-term laboratory decay tests, and some positive results have been obtained after 2-4 years of outdoor exposure. The two antioxidants principally examined, propyl gallate and butylated hydroxytoluene, are low cost and, since both are f...
T Schultz, D D Nicholas, W Henry, C Pittman, D Wipf, B Goodell
Chemical and biological investigations of double-vacuum treated windows after 5 years in service
1983 - IRG/WP 3219
In 1980 The Swedish Wood Preservation Institute initiated an investigation to study the degradation of TBTO and possible fungal attack in double-vacuum treated window joinery in service during 5 years. A hospital in Gothenburg was chosen that was built during 1969 to 1976. Both untreated and double-vacuum treated windows of Pinus sylvestris were used. A brown alkyl oil type paint (Nordsjö system ...
J Jermer, M-L Edlund, B Henningsson, W Hintze, S V Ohlsson
Immunolocalization of extracellular metabolites from Poria placenta
1988 - IRG/WP 1361
Polyclonal antisera produced to Poria placenta extracellular metabolites was used in immuno-fluoresence microscopy and immuno-gold TEM studies. In the fluorescence work, labelling of Poria placenta hyphae in wet fixed wood material was observed but not in infected wood which was oven dried prior to sectioning and immunolabelling. TEM studies provided better resolution, with gold labelling detected...
B Goodell, G F Daniel, J Jellison, T Nilsson
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
Field study: Wood degradation pattern in buildings and utility poles in tropical climates of Nigeria
1992 - IRG/WP 92-1521
The paper is the result of five years field study of wood degradation patterns in three ecological forest zones (Guinea Savannah, Tropical rain forest and mangrove forest zones, respectively). It involved 800 residential buildings and 700 electric overhead transmission poles. The methodology used was a modified Eslyn (6) test. A high rate of Ascomycetes and Basidiomycetes attack especially on the ...
E O Onuorah
Fungal detoxification of organotin biocides
1985 - IRG/WP 1258
The ability of a range of wood decaying fungi to inactivate bis(tri-n-butyltin) oxide (TnBTO) in the extracellular growth medium, in stationary liquid culture was determined. A distinction between the ability to tolerate the fungicide and to inactivate it was made: the white-rot organism Coriolus versicolor being the most efficient inactivator. In an attempt to determine the extracellular agents r...
P S Belford, D J Dickinson
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
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
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
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
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
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
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
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
Degradation of resin constituents in various wood species by the white rot fungus Bjerkandera sp. strain BOS55
1999 - IRG/WP 99-10301
In previous studies, the white-rot fungus Bjerkandera sp. strain BOS55 was shown to cause extensive degradation of lipophilic extractives (resin) in Scots pine wood. Further research was carried out in order to investigate the ability of Bjerkandera sp. for reducing resinous constituents in various softwood (Douglas fir, larch and spruce) and hardwood species (birch, beech and poplar). The greates...
J Dorado, T A Van Beek, F W Claassen, R Sierra-Alvarez
Effect of fungal degradation on the chemical composition of acetylated beech wood
2003 - IRG/WP 03-40267
This study investigated the impact of fungal attack on the chemical composition of acetylated wood. Beech wood acetylated to different degrees was exposed to decay by the white-rot fungus Trametes versicolor under solid-state fermentation conditions. Laboratory soil-bed assays were also conducted to study the degradation of acetylated wood by soft rot fungi and other soil-inhabiting microorganisms...
H Militz, Dong-won Son, L Gómez-Hernández, R Sierra-Alvarez
Influence of the content of organic matter of soil on the degradation of wood by soft rot fungi
1970 - IRG/WP 27
The degradation of wood specimen burried in the soil by soft rot fungi is influenced by a number of factors. These are in particular the water holding capacity, water content, content of organic matter, pH, content of mineral nutritive substances etc. The results of the interlaboratory tests, carried out within the IRG/WP let presume that the intensity of wood degradation occurs proportionally inv...
O Wälchli
Degradation of woods by obligately anaerobic fungi
1990 - IRG/WP 1452
Little is known about the processes occurring during the degradation of wood by obligately anaerobic fungi. When woods from a range of hardwood species were incubated for 11 days with a strain of the Chytrid Neocallimastix frontalis many of the woods were measurably fermented; Fagus sylvatica (23%) was the most highly degraded. Microscopic examination of Populus tremuloides wood after incubation w...
K N Joblin, G E Naylor
Determination of thermal degradation of isothiazolone treated wood
1997 - IRG/WP 97-30154
Wood treated with 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one was the subject of thermal degradation study. The study included burning isothiazolone treated wood under various temperatures with and without oxygen. The result showed that no harmful combustion products, such as polychlorinated dibenzo-p-dioxins, polychlorinated dibenzo-p-furans and polychlorinated biphenyls, were detected. These fin...
Bing Yu
Analysis of the degradation of carbohydrates by blue-stain fungi
1990 - IRG/WP 1457
The topic of the degradative ability of blue-stain fungi literature is not clear. Many authors support the idea that those fungi don't have enzymatic capability to decay the wall of the ligneous cells. However, others have found some decay activity. In this study, we have attempted to analyze which wall cells soluble carbohydrates are metabolized by some blue-stain fungi, found in Spain. ...
M T De Troya, A M Navarrete, E Relano
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 4: Conversion reactions during storage
1974 - IRG/WP 332
Precipitates simulating those produced in wood by preservative fixation reactions were prepared by the reduction of Boliden K 33 and Celcure AP solutions with hydrogen peroxide and hydrazine. The pH changes on aging at 20 and 50°C were studied and related to the chemistry of fixation previously described. Hydrolysis of copper arsenates may render arsenic acid temporarily water soluble pending pre...
S-E Dahlgren
Extracellular laccase production in brown-rot fungus Coniophora puteana
2001 - IRG/WP 01-10391
Coniophora puteana, one of representing brown-rot fungus, was investigated in terms of extracellular ligninolytic enzyme production. Three fungal strains of C. puteana were inoculated in liquid culture medium with sawdust of pine and oak wood. Extracellular laccase production was observed in some strains of C. puteana in the culture medium with sawdust of oak wood. The highest activity occurred at...
Kwang-Ho Lee, Seung-Gon Wi, Yoon Soo Kim
Immunolabelling studies on the detection of enzymes during the degradation of wood by Phanerochaete chrysosporium
1988 - IRG/WP 1364
The degradation of lignin in native lignocellulosic substrates by white rot fungi is poorly understood. Biochemical studies have shown the involvement of a number extracellular ligninolytic enzymes released by white rot fungi which are capable of the oxidative conversion of DHP's (lignin model compounds) in vitro, but to date conclusive evidence for occurrence of these enzymes in wood und...
G F Daniel, T Nilsson, B Pettersson