Your search resulted in 456 documents. Displaying 25 entries per page.
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
The yeast Pichia sp. As a short-term biological control agent to fungal spoilage of sawn softwood timber
2000 - IRG/WP 00-10362
Previous work has found isolates of the yeast Pichia to be a successful biological control agent toward moulding of fruits. An isolate was tested for the ability to protect sapwood of Pinus sylvestris timber against visual degrade by surface growth of moulds and staining fungi. Successful protection of autoclaved wood sprayed with a mixture of common wood moulding fungi was achieved when the yeast...
C Payne, H J Staines, A Bruce
Evaluation of New Zealand staining fungi for degradation of radiata pine
1999 - IRG/WP 99-10310
This investigation sought to determine the potential of selected NZ staining fungi to induce weight loss and changes in toughness (impact bending strength) and composition in unseasoned radiata pine sapwood. Furthermore, assays were performed to eveluate enzyme production by staining fungi. Sets of side-matched specimens were inoculated with Ophiostoma floccosum, Sphaeropsis sapinea and O. plurian...
A Schirp, R L Farrell, B Kreber
Immunogold localisation of catalytic domain of endocellulase in the cellulosic substrates
1997 - IRG/WP 97-10205
The reaction of catalytic domain of endocellulase on the cellulosic substrates was visualised by using immunogold labelling procedures to obtain a better understanding of the mechanism of enzymatic cellulose hydrolysis. Polyclonal antibody was produced against the catalytic domain of endo-l, 4-ß-glucanase (EGI) from a ruminal anaerobic bacterium Ruminococcus albus F-40. Immuno-TEM works showed th...
Yoon Soo Kim, Seung-Gon Wi, Kyu Ho Myung, K Ohmiya, S Karita
Alternative technologies for wood wastes recycling - Part B: Biotreatment of PCP- and creosote-treated wood
1998 - IRG/WP 98-50101-18 b
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
S Legay, P Marchal, G Labat
Comparison of decay rates of preservative-treated stakes in field and fungus cellar tests. Results after 40 months fungal cellar exposure
1983 - IRG/WP 2200
Decay rates of preservative-treated Pinus radiata stakes during 40 months exposure in the FRI fungus cellar were compared with those of similarly treated material in a field test. Decay rates in the fungus cellar were from 4 to 100 times higher than in the field, although for the majority of preservatives the rate was between 7 and 12 times higher. The lag phase before onset of decay, noticeable w...
M E Hedley
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
Fungal colonization of CCA-treated decking
2003 - IRG/WP 03-10491
The identification of fungi isolated from CCA treated decking in Vancouver is reported. About two thousands locations were sampled from over sixty boards recovered from six decks. Wood chips from each location were placed onto four different types of media. Of the large number of isolates obtained, around 15% were obtained from the interior of the boards. The succession of colonization in CCA-...
S Choi, J N R Ruddick, P I Morris
Studies on the fungicidal effectiveness of a petrol derived product as a creosote alternative
1986 - IRG/WP 3384
This work, appears first because of the necessity to find out a profitable use for a residual product of the petrol pyrolisis, and second, because the lack of high natural durability wood used until now-a-days to build posts and sleepers in creosote lacking countries. Our main objective was pointed to the characterization of this new product and to find out the effectiveness against the wood-destr...
A M Navarrete, M T De Troya.
Development on Damage Functions of Wood Decay for Building Envelope Design
2005 - IRG/WP 05-10556
For the hygrothermal analyses of building envelope systems for insulation design, we tried a natural decay test of wetted wood specimens without any inoculation of fungi. Three principal experimental types: under steady-state conditions (Experiment A), at a cyclic water dripping under Non-steady conditions (Experiment B) and at a cyclic water dipping under-steady conditions (Experiment C), were ca...
H Suzuki, Y Kitadani, K Suzuki, A Iwamae, H Nagai
Photo-discoloration and Degradation of Wood and its Stabilisation by Modification with Benzoyl Chloride
2004 - IRG/WP 04-40274
Photo degradation of Pinus roxburghii (chir pine) and Hevea brasiliensis (rubber wood) was studied under artificial accelerated weathering conditions in a Xenon test chamber. The irradiated samples were analyzed for color changes and chemical changes. Analysis of colour changes in wood surfaces by UV-Vis. irradiation was carried out using a colour measuring (CIELAB) system and chemical changes ...
K K Pandey
Kinetic of the wood degradation produced by wood decay fung
1993 - IRG/WP 93-20016
The degradation degree of a wooden structure has a direct influence on its loss of mechanical strength. It's necessary to deepen in non destructive techniques which permit to extrapolate the results obtained in laboratory to structural timber used in the building's construction. This work studies the relationship existing between the pulse velocity of ultrasonic waves and the wei...
M T De Troya, A M Navarrete, A Sanchez, V Bucur
Bending creep test of plywoods under long term exposure to fungal attack
1981 - IRG/WP 2163
Bending creep test and decay test were coupled in order to evaluate the durability of structural plywoods and preservative efficacy. Experimental blocks, 5.0 x 1.2 cm² section x 35.0 cm length, were impregnated with distilled water and inoculated with mycelial fragments of test fungus. Polyethylene bags stretched with metal frame were used as decay chambers. The chambers containing inoculated blo...
M Takahashi
The influence of gaseous oxygen concentration on fungal growth rates, biomass production and wood decay
1998 - IRG/WP 98-10283
The effects of air and several levels of oxygen balanced with nitrogen (% oxygen (v/v) nitrogen to 100%) on growth rates, biomass production and wood decay were investigated. The best technique for measuring daily growth rates in anaerobic jars was found to be by using 40 mm petri dishes which were attached to the walls of the jars. At the end of the test period the same petri dishes were also use...
S M Kazemi, D J Dickinson, R J Murphy
Natural durability of Iranian saxual wood (Haloxylon persicum) against the fungal decay
1991 - IRG/WP 1515
Haloxylon persicum is vidly planted in the deserfic region of Iran. At the present time, in the age of 30, these small trees are ready for cutting for the different uses, specially for rural buildings. But there's any knowledge about its durability. In this study the laboratory tests were carried out in accordance to European Standard. 5 fungi were used as: Trametes versicolor, Coniophora...
D Parsapajouh, F H Schweingruber, K Richter
Degradation of the gelatinous-layer in aspen and rubber wood by the blue stain fungus Lasiodiplodia theobromae
1996 - IRG/WP 96-10168
Studies on the degradative ability of the blue stain fungus Lasiodiplodia theobromae Pat. have shown several strains to cause significant weight losses (i.e. ca 20%) in the temperate and tropical wood species, aspen (Populus tremula) and rubber wood (Hevea brasiliensis). In addition to the consumption of soluble carbohydrates and extractives, major changes in the ultrastructure of fibre cell walls...
O Encinas, G F Daniel
Study of the degradation of retified wood through ultrasonic and gravimetric techniques
1994 - IRG/WP 94-40030
One of the non-polluting processes that increase the natural durability of wood is a thermal treatment in an atmosphere poor in oxygen, producing what is normally denominated "retified wood". In this study the validity of a non-destructive technique (ultrasound) in order to determine the biodegradation suffered by wood across time has been studied. For this reason, the behavior of a wood species (...
D T De Troya, A M Navarrete
Soft rot studies on CCA treated eucalypt power transmission poles
1981 - IRG/WP 1132
Initial results found for sixty CCA treated eucalypt poles, from a soft-rot survey are discussed. Retentions of CCA within above and below ground pole samples were variable. The variation was attributed mostly to biodegradation and effect of soil environment, rather than leaching. Bacterial decay was found in many poles and was severe in some cases. Although found in the presence of soft-rot decay...
L E Leightley
Identification of terminal structures in cellulose degraded by the brown-rot fungus Postia placenta
1989 - IRG/WP 1389
To gain insight into the biochemical mechanism employed by brown-rot fungi to depolymerize cellulose, we identified the end-groups of chemically pure cellulose that had been depolymerized by the brown-rot fungus, Postia placenta. The depolymerized cellulose was acid hydrolyzed and the anion fractions isolated by ion chromatography. Sugar acids were identified by gas chromatographic and mass spectr...
T K Kirk, T L Highley, R E Ibach, M D Mozuch
Changed permeability and surface properties of hornbeam wood due to its degradation by erosive strain of Phanerochaete chrysosporium
2004 - IRG/WP 04-40290
Specimens of hornbeam wood were submitted to a medium-term degradations by erosive fungus Phanerochaete chrysosporium. Biodegradations of specimens resulted in their apparent structural alterations, changes in permeability and increased intensity of interactions with polar liquids. Modified physical properties of biodegraded wood may significantly influence its penetration with polar media and che...
R Solár, S Kurjatko, L Reinprecht, M Mamon, V Vacek
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 2: Laboratory fungal bioassays
2000 - IRG/WP 00-20204
Extracts from sawmill residues of the naturally durable white cypress, Callitris glaucophylla were tested for fungicidal activity in a series of laboratory bioassays. The effects of different extraction solvents, techniques and sources of material on the biocidal efficacy of the resultant extracts were evaluated. Soil jar decay tests were used initially however, contractual time constraints necess...
M A Powell, L M Stephens, L Francis, M J Kennedy
The efficacy of remedial treatments for controlling fungal decay in window millwork used in the United States
1987 - IRG/WP 3432
Conventional window millwork was subjected to basidiomycete decay by inoculation and sampled for active growth of the decay fungus before and eight months after remedial preservative treatment with fused disodium octaborate rods (IMPEL) at boric acid levels of 1.5 and 4.0 kg/m³ or liquid bifluoride injections (IMPROSOL) at 1 kg/m³. The elimination of decay fungus after remedial treatment was nea...
M G Dietz, E L Schmidt
Enzyme systems of bacterial isolates from ponded logs - Potentials of pectin and/or starch degradation
2000 - IRG/WP 00-10378
This paper deals with the degradation potentials of wood constituents by the bacterial isolates from ponded logs. The potentials to degrade pectin as a constituent of pit-tori as well as starch existing in ray parenchyma cells in the areas of sap- and transition wood with the isolates were examined. The pectinase activity was investigated by means of the degradation degree of a carrot strip used a...
S Doi, S Ohta
Fungal Stain Development in Canadian Hardwood Logs
2004 - IRG/WP 04-10505
In most sawmills around the world, trees are harvested into logs and stored in the forest or in a log yard for a period of time before being sawn into lumber. These logs may be attacked by various pigmented fungi, which results in staining of the wood. Since hardwood species are used to a great extent in furniture manufacturing and in the making of other valuable wood products, the reduction of wo...
Dian-Qing Yang, M-C Bisson
Moisture uptake and volumetric swelling as probable factors also affecting leaching in CCA-treated wood. A preliminary study of treated Eucalyptus saligna sapwood
2003 - IRG/WP 03-30318
IRG/WP 03-30318
A number of factors affecting leaching of CCA from treated wood have been variously investigated and discussed. However, the possible effects of moisture movement in treated timbers on leaching have not received attention yet. The present study examines and compares moisture uptake and volumetric swelling in CCA-treated and untreated sapwood of Eucalyptus saligna, and tries to establish a correl...
R Venkatasamy