Your search resulted in 3468 documents. Displaying 25 entries per page.
Biodegradation of acetylated southern pine and aspen composition boards
1994 - IRG/WP 94-40020
This objective of this study was to investigate the influence of the acetylation treated wood fiber, Phenol-formaldehyde resin content level, two wood fiber species, three fungi species on the dimensional stability and decay resistence of high density composition boards. A standard ASTM method was used to evaluate weight loss and thickness change. The linear shrinkage and expansion of each species...
P Chow, T Harp, R Meimban, J A Youngquist, R M Powell
Analysis of degradation observed on ancient wooden objects buried underground
2001 - IRG/WP 01-10403
Ancient wooden objects were sometimes excavated from the moat of mounded tombs in Japan. Such wooden objects were in the shape of a sunshade, bird, shield, pole, yugi(a bag that holds arrows) among others. Archaeologists discussed the usage of such shaped objects, but no one could clearly explain their use. Some objects were observed using an ordinary microscope. Deterioration by bacteria was foun...
H Sakai
Effects of artificial UV weathering and soft rot decay on heat treated wood
2005 - IRG/WP 05-40302
Oil and inert gas oven heat treated pine wood strips 100 µm thick were mildly heat treated (200°C, 30 mins linseed oil, 120 mins oven). Following treatment, specimens were exposed to UV weathering (300 hours) and decay by the soft rot fungus, Chaetomium globosum. The effects of each treatment were assessed by zero span tensile testing, microscopy and by FTIR.
Tensile testing of heat treated s...
M D C Hale, S C Ghosh, M J Spear
Relative performances of DNBP and CCA wood preservatives in accelerated decay tests
1988 - IRG/WP 3496
The effectiveness of 2-sec-butyl-4,6-dinitrophenol (DNBP) was compared with that of CCA. Test blocks of Pinus patula and Eucalyptus grandis were impregnated to precisely known retentions of approximately 3, 6, and 10 kg/m³ CCA and solvent-borne DNBP respectively. They were then challenged in decay tests comprising soil burial and exposure to monocultures of Chaetomium globosum, Coriolus versicolo...
W H Schnippenkoetter, L D Abraham, A A W Baecker
Soft rot decay of Eucalyptus maculata Hook. in different soils from Queensland, Australia
1980 - IRG/WP 1113
In the present work, different Queensland soils were chosen and their gross effects on the decay of treated and untreated Eucalyptus maculata examined. The soils were also amended with various levels of phosphate to study the response of the wood decay mycota to an increasing supply of this nutrient. Phosphate amendment was chosen because of the wide-scale use of superphosphate on Queensland soils...
L E Leightley, I W Russell
Soft rot fungi as possible sources of odor in impregnated wood in buildings
1993 - IRG/WP 93-20013
Wood preservatives are frequently used inside houses. In several cases impregnated wood, particularly when used in crawlspaces or other near-ground constructions, has been found to be a source of odor. Mold fungi, soft rot fungi actinomycetes or bacteria growing on impregnated wood are possible producers of the odor. Analyses of volatile emissions from impregnated wood with odor and pure cultures ...
J Bjurman, J Kristensson
Effect of light and ventilation condition on the rate of wood decay by the brown rot basidiomycete, Tyromyces palustris
1991 - IRG/WP 1517
Effect of light and the ventilation conditions of incubation jars on the wood decay by Tyromyces palustris (Berk. et Curt.) Murr. FFPRI 0507 was investigated. Under no irradiation of light, the ventilation conditions gave extensive effect on mass loss of the test pieces when the culturing was performed with culture medium designated in Japanese Industrial Standard (JIS) A 9302 (Medium A; glucose 4...
T Suzuki, M Higaki
Ultrastructure of degraded, CCA-treated Pinus radiata wood from a marine pile
1990 - IRG/WP 1461
During an inspection of marine piles, 12 years after installation, severe degradation was noted on one of them in the vicinity of a corroded eye-bolt. The wood was dark brown in colour and tended to crumble easily. Wood fragments were examined by light microscopy and scanning and transmission electron microscopy and were also analysed for carbohydrates and lignin. Light microscopy showed numerous ...
A P Singh, M E Hedley
The dry rot fungus Serpula lacrymans, its growth and damaging of wood
2004 - IRG/WP 04-10511
The dry rot fungus (Serpula lacrymans) is one of the most dangerous wood rotting fungi, especially in the built environment. In our mycological laboratory more experiments with this fungus have been carried out aimed at:- its growth under stable and variable climatic conditions, - its possibility to attack
either natural wood of different species and also modified wood primary pre-treated with ...
L Reinprecht
Novel observations on the micromorphology of soft rot attack of wood
1996 - IRG/WP 96-10176
Electron microscopic examinations of decaying Pinus radiata horticultural posts which had been treated with CCA preservative prior to being placed in service about nine years ago showed the presence of soft rot fungi and tunnelling bacteria. Some novel observations on the micromorphology of the soft-rotted areas of tracheid walls are described here. The micromorphology of soft-rotted areas was hig...
A P Singh, R N Wakeling
Practical consequences of the clarification of the chemical mechanism of CCA fixation to wood
1983 - IRG/WP 3220
Practical consequences derived from the chemical investigation of the mechanism of fixation of CCA to the wood constituents are discussed. Among these, formulas for the calculation of the time of hexavalent chrome fixation are presented. Furthermore, three parameters are shown to be important to the long-term effectiveness of CCA-treated timber: (i) the temperature of treatment, (ii) the initial p...
A Pizzi
Evaluation of substituted isothiazolone as a potential new wood preservative
1984 - IRG/WP 3306
Laboratory decay tests were carried out with isothiazolone (4,5-dichloro-2-n-octyl-4-isothiazolone-3-one) treated wood. This compound was found to be extremely effective against three common wood decaying brown-rot fungi, exhibiting toxic threshold values in the range of 0.37 to 0.50 kg/m³. For the white-rot fungus, Coriolus versicolor, the toxic threshold values for treated pine and sweetgum wer...
D D Nicholas, A F Preston, D E Greenley, S V Parikh
An electron spin resonance study of manganese changes in wood decayed by the brown-rot fungus, Postia placenta
1988 - IRG/WP 1359
Electron spin resonance (ESR) spectrometry was used to examine wood decay by the brown-rot fungus, Postia placenta. Wood slivers of Douglas-fir, white fir, redwood, sweetgum and yellow poplar were incubated for 4 weeks in custom-made quartz ESR tubes with or without Postia placenta. In all wood species without fungus, a weak partially resolved signal (about g=2, presumably due to manganese) was de...
B Illman, D C Meinholtz, T L Highley
The effect of hemicellulose degradation on the mechanical properties of wood during brown rot decay
2001 - IRG/WP 01-20219
Incipient decay of wood by brown rot fungi causes measurable strength losses in wood before measurable weight loss occurs. Previous studies have shown that the high levels of strength loss that occur during incipient brown rot decay may be related to loss in hemicellulose. This paper investigates the effect of decay on hemicellulose composition and the relationship to the mechanical properties of ...
S F Curling, C A Clausen, J E Winandy
Evaluation of fungal remediation of creosote treated wood
1998 - IRG/WP 98-50101-25
Biotechnological remediation of creosote treated wood may be of interest in connection with novel recycling processes. White rot fungi and/or their ligninolytic enzyme systems are supposed to be valuable tools for such processes. This paper reports about results achieved when creosoted wood was treated in solid substrate fermentation with selected white rot fungi after different extraction procedu...
K Messner, S Böhmer
Evidence for wood cell wall degradation by the blue stain fungus Botryodiplodia theobromae Pat
1994 - IRG/WP 94-10077
Botryodiplodia theobromae Pat., a world wide ubiquitous polyfagus sapstain fungus, was found able to destroy the cell walls of birch fibres (Betula verrucosa Ehrh.) but not Caribbean (Pinus caribaea var. hondurensis Barr. and Golf.) and Scots pine (Pinus sylvestris L.) tracheids. The fungus caused characteristic erosion of fibre cell walls similar to soft rot type 2; destruction of the S1 - S2 int...
O Encinas, G F Daniel
Moisture requirements and wood degradation of pine and spruce wood by some Basidiomycetes-fungi
1989 - IRG/WP 1406
The minimum moisture requirements for the growth of the brown rot fungi, Coniophora puteana, Gloeophyllum trabeum and Serpula lacrymans were near or above the fibre saturation point of pine and spruce, sap and heartwood, during 160 days incubation according to the standard method EN 113. The moisture of wood for the optimum growth of Coniophora puteana and Serpula lacrymans was about 35-80% and fo...
H Viitanen, A-C Ritschkoff
Formation of soft rot cavities in relation to concentric layers in wood fibre walls
1983 - IRG/WP 1185
A large number of timber species attacked by soft rot have been examined using light microscopy. The S2 layers in a large number of the timbers exhibited special structural features in the form of thin concentric layers. Several observations indicate that these layers may be characterised as "weak" zones by being more easily degradable than the surrounding wall layers. The chemical structure of th...
T Nilsson, G F Daniel
Acetylated solid wood. Laboratory durability test (part 2) and field trials
1995 - IRG/WP 95-40048
Degradation of acetylated beech, pine and poplar by soft rot fungi was related to strength loss in a laboratory test. No strength loss was noticed for poplar acetylated to a weight percent gain (WPG) of more than 11.2% and beech with a WPG of 12.8%. Several field trials were set up to determine the durability of acetylated products in practice. They included a field test to determine the durabilit...
E P J Beckers, H Militz, M Stevens
Changes in pore structure and cell wall volume in wood decayed by brown- and white-rot fungi
1991 - IRG/WP 1501
Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (=Poria) placenta or Phanerochaete chrysosporium in soil-block cultures. Decay was terminated at various weight losses, and the pore volumes available to probes of various molecular weight and diameter were determined by the solute exclusion technique (Stone, J.E. and A.M. Scallan. 1968. Cellulose Chem. Technol. 2, 343-358.)....
D S Flournoy
Soft rot decay of Belian (Eusideroxylon zwageri) wood
1995 - IRG/WP 95-10119
The heartwood of Belian (Eusideroxylon zwageri), an East Malaysian timber species, is naturally durable due to its certain unique anatomical features and high content of extractives. The timber can tolerate years of exposure to hazardous conditions in ground contact and other situations without any significant loss in its strength. A few Belian transmission poles sampled from one locality in Saraw...
A H H Wong, A P Singh
Soft rot - Soil burial - Tests. Influence of the water content of the soil on wood decay
1972 - IRG/WP 212
The decay of wood samples buried in the soil is influenced by various factors. Decisive are the water content, the content of organic substances, pH-value content of mineral nutritive substances etc. of the soil. For the tests, carried out by the EMPA until now, it was always started with a water content of 35%, refered to the dry weight of the EMPA-soil = 75% of its water capacity. In order to in...
O Wälchli
Decay resistance of Siberian larch wood against brown rot fungi - Part 2. The effect of genetic variation
1998 - IRG/WP 98-10287
Wood natural decay resistance is mainly restricted in the heartwood part of tree and based on wood microstructure and chemical composition. However, the variation of decay resistant in different wood species is vide and the effect of genotype on decay resistance of Siberian larch wood grown in Finland is not known. The aim of this work was to find out the variation on decay resistance of Siberian ...
H Viitanen, L Paajanen, T Nikkanen, P Velling
Soluble nutrient content in wood and its susceptibility to fungal discoloration and decay in above ground and ground tests
2000 - IRG/WP 00-10336
The objective of this comprehensive study was to reveal the impact of soluble nutrients in wood on its susceptibility to fungal discoloration and decay in various tests, which is important for the test methodology and standardisation. Seven tests were carried out including pure culture above and ground contact tests, above ground field test and laboratory ground contact tests. The samples containi...
O M Caballero, N Terziev
The critical moisture and temperature conditions for the growth of some mould fungi and the brown rot fungus Coniophora puteana on wood
1988 - IRG/WP 1369
The growth of some mould fungi on pine and spruce sapwood was studied in 40 different constant moisture and temperature conditions. The temperature range was between +10 and +40°C and the relative humidities varied from 76 to 100% relative humidity (RH). The incubation time was 12 weeks. The mixed mould inoculation used included typical fungi growing on wood: Aspergillus versicolor, Cladosporium ...
H Viitanen, L Paajanen