Your search resulted in 798 documents. Displaying 25 entries per page.
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
Preliminary studies of the decay mechanism of some brown-rot fungi
1989 - IRG/WP 1402
The importance of the enzymatic degradation of hemicellulose and cellulose by brown-rot fungi is still under discussion. Endo-ß-1,4-xylanase and endoglucanase activities of Coniophora puteana and Poria placenta cultures were measured by the increase in reducing groups. Enzymes were produced in liquid and solid sawdust based culture media. Enzyme activities were measured in two, four and eight wee...
A-C Ritschkoff, H Viitanen
A prototypical needle-incisor for refractory timber
1995 - IRG/WP 95-40041
A needle-incisor was manufactured for trial. This machine has an incising mechanism that a set of needles held by a rotary plate incises timber which is moved toward the front simultaneously, and then another set of needles incises a new part of the timber. Timber is incised by recycling the process. Timber incised of 4400 incisons/m² with the depth of 56 mm by 2.8 mm-diameter needles on all the ...
A Yakuwa, H Endoh, M Mori, S Doi
Butt-end incising to improve penetration and retention of CCA in Eucalyptus saligna telegraph poles in Kenya: Preliminary results
2002 - IRG/WP 02-40243
Incising to improve penetration and retention of Copper Chrome Arsenate (CCA) in the butt end of Eucalyptus saligna telegraph poles was investigated. Debarked, seasoned (15% MC) butt-end samples from full size telegraph poles were incised using four patterns of incisions, sealed at
the top or small diameter end, and pressure treated, together with un-incised samples, with CCA-C (3.0% oxide typ...
R Venkatasamy
The growth and behaviour of Australian isolates of dry rot fungi, mainly Serpula lacrymans (Schum. ex Fr.) S.F. Gray. A comparision with the world literature
1983 - IRG/WP 1190
In Australia Serpula lacrymans occupies a rather unique environment, being restricted to growth within basal regions of buildings containing masonry. Its rate of timber attack in these situations appears to be far faster than that experienced in other parts of the world. Therefore the question arises as to how Australian isolates (particularly 16508 which has become a "standard" test fungus for so...
J D Thornton, O Collett
A preliminary assessment of the penetration into wood achieved by bodied mayonnaise emulsion wood preservatives
1992 - IRG/WP 92-3725
Five different commercial formulations of bodied mayonnaise emulsions were applied to samples of Scots pine (Pinus sylvestris) sapwood as recommended by the manufacturers. Penetration and loading characteristics were determined by measuring the distribution profiles of the active ingredients after various intervals of time. The changes in the general appearance of the emulsions on the surface of t...
G E Holland, R J Orsler
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
Creosote for wood preservation
1971 - IRG/WP 36
By creosote one usually means coal tar creosote, although there are creosotes of other origin. For example, wood tar creosote is a product of wood distillation. It is, in fact, in this connection that the word 'creosote' was first used. Early in the nineteenth century the oily product obtained by distilling wood was said to have an odour which resembled 'smoked meat&...
Anonymous
Biochemical aspects of white-rot and brown-rot decay
1987 - IRG/WP 1319
This paper presents an overview of the decomposition of wood by white- and brown-rot fungi - the most important and potent of known wood-decay fungi. These organisms are unique among cellulose destroyers because of their strong capability to enzymatically degrade lignified material. Special emphasis is given to the following aspects of wood decomposition by white- and brown-rot fungi:
(1) effects...
T L Highley
An investigation of the effects of pre-steaming on the treatment of sawn spruce timber with Celcure A, a copper/chrome/arsenic preservative
1981 - IRG/WP 3180
Difficulties in the treatment of spruce using standard vacuum/pressure techniques with both water-borne and organic solvent preservatives are well known. The growth characteristics of spruces (Picea spp) make them attractive candidates for forestry schemes. In 1975 the UK Forestry Commission had about 400 000 hectares, about 20% of total UK forest area, planted with Sitka spruce (Picea sitchensis)...
C R Coggins
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
Preliminary studies to assess the effects of aeration and lowered humidity on the decay capacity, growth and survival of the dry rot fungus Serpula lacrymans (Wulf ex. Fr.)
1997 - IRG/WP 97-10208
Novel microcosms were used to test separately the effects of aeration and humidity on the decay capacity, linear spread and survival of Serpula lacrymans. The application of a pumped air supply resulted in an effective cessation of fungal activity when all but the lowest of the air flow rates was used. Furthermore, the lowest air flow rate caused marked growth tropisms away from the stress. In sep...
G A Low, J W Palfreyman, N A White, H J Staines, A Bruce
Serpula lacrymans, The Dry Rot Fungus and its Tolerance towards Copper-based Wood Preservatives
2005 - IRG/WP 05-10555
Serpula lacrymans (Wulfen : Fries) Schröter, the dry rot fungus, is considered the most economically important wood decay fungus in temperate regions of the world i.e. northern Europe, Japan and Australia. Previously copper based wood preservatives were the most commonly used preservatives for pressure treatment of wood for building constructions. Because of a suspicion about tolerance toward cop...
A C Steenkjær Hastrup, F Green III, C A Clausen, B Jensen
Ability of chitosans to limit wood decay under laboratory conditions.
2004 - IRG/WP 04-30339
Chitosans have recently been explored for controlling a number of plant pathogenic fungi and have shown some promise for controlling stain fungi on wood. The potential for using chitosans either alone or in combination with copper sulfate to protect wood from fungal decay was explored using maple veneers. Chitosan treatment reduce weight losses caused by two brown rot and one white rot fungi, howe...
M Maoz, J J Morrell
Generation of hydroxyl radical by the brown-rot fungus, Postia placenta
1988 - IRG/WP 1360
In an electron spin resonance (ESR) survey of various liquid cultures and wood slivers innoculated with the brown-rot fungus, Postia placenta, the spin trap dimethyl-l-pyrroline N-oxide (DMPO) was used to detect the presence of the hydroxyl radical. The ESR spectra for the paramagnetic DMPO- hydroxyl radical adduct was observed in (1) nitrogen-limited, liquid cultures having 1.0% glucose or 0.1% c...
B Illman, D C Meinholtz, T L Highley
Efficiency of wood impregnation processes
1980 - IRG/WP 3151
Many wood impregnation processes have been in use for a very long time, up to 150 years, but they have not been progressively modified. This paper considers impregnation processes in relation to current requirements, particularly impregnation efficiency and energy consumption. The term 'pore' is used throughout in its physical sense and is not confined to botanical 'pore...
B A Richardson
Preliminary modelling of methylisothiocyanate movement through Douglas fir transmission poles
1988 - IRG/WP 3466
Methylisothiocyanate is a volatile solid that is the active ingredient of several registered and experimental wood fumigants. Information on the sorption and diffusion of this chemical in Douglas-fir heartwood and sapwood was used to develop a two-dimensional model of fumigant movement within a single horizontal cross-section of a transmission pole. The model indicated that dry wood (14% MC) stron...
A R Zahora, P E Humphrey, J J Morrell
Accelerated laboratory testing of preservatives on 13 North American wood species
1999 - IRG/WP 99-30201
The ability of selected water and solvent based biocides to protect wood against fungal attack was evaluated on 13 North American wood species using 7 decay fungi in a modified soil block test. Most preservatives were capable of providing protection at their recommended above ground and soil contact use levels. Many decay fungi caused substantial weight losses on blocks treated with chlorothalonil...
J J Morrell, C M Freitag
Fenton's reagent as a modification tool in brown-rot decay
1996 - IRG/WP 96-10155
A biomimetic approach was used to clarify the role and importance of the Fenton-type reaction in the carbohydrate degradation by brown-rot fungi. Spruce sawdust and microcrystalline cellulose were modified in the H2O2/Fe(II) treatment. The degree of hydrolysis of the pretreated spruce sawdust was clearly increased with the complete cellulase (Econase), purified endoglucanase from Trichoderma reese...
M Rättö, A-C Ritschkoff, J Buchert, L Viikari
Preservative effect of cellulose insulation material against some mould fungi and brown rot fungus Coniophora puteana in pine sapwood
1991 - IRG/WP 1484
The influence of mineral wool and loose-fill cellulose wool on biodeterioration of pine sapwood was studied. The test fungi were mould fungi Aspergillus versicolor, Cladosporium sphaerospermum, Penicillium sp. and Aureobasidium pullullans and brown rot fungus Coniophora puteana. Cellulose wool inhibited the growth of mould fungi on the face of wood contacted with insulation material at RH of 97 an...
H Viitanen
Biochemical relationships between biodegradation of cellulose and formation of oxalic acid in brown-rot wood decay
1991 - IRG/WP 1472
Non-enzymic hydrolysis of cellulose with low concentrations of oxalic acid was examined. The incubation of pine wood pulp with 1% oxalic acid (pH 1.3) at 35°C for 4 weeks reduced the original viscosity to 60%. Reducing sugars were liberated from various cellulosic samples by the oxalic acid treatment. However, crystallinities of cellulose in those samples did not change before and after the treat...
M Shimada, Y Akamatsu, A Ohta, M Takahashi
Penetration of surface applied deltamethrin micro-emulsion formulations in four European timber species
1994 - IRG/WP 94-20030
The Netherland's Government, in line with many other European Governments initiated a programme (KWS2000) aimed at significantly reducing the emission of volatile organic compounds by the year 2000. As part of this programme a research project is currently underway to evaluate the potential for replacing organic solvent based remedial treatments with micro-emulsion formulations of the sam...
P Esser, W L D Suitela, A J Pendlebury
Behaviour of some selective Indian species towards treatment with solvent based water repellent preservative
1984 - IRG/WP 3309
This paper discusses a solvent based preservative using PCP and a water repellent for preserving three species of timber commonly used in India for the manufacture of doors and windows. It examines the method of treatment to achieve desired levels of penetration and retention of the preservative-cum-water repellent, and tests made on these timbers to examine the success of the processing methods a...
V R Sonti, B Chatterjee
A technique for assessing the preventive efficacy against decay fungi of preservative treatments applied to wood
1988 - IRG/WP 2309
A method is described in which test blocks with envelope preservative treatments can be challenged by selected test fungi previously established on an untreated feeder block. The progress of the test fungus through the treated zone is monitored using novel baits or sensors inserted in holes drilled into blocks to within predetermined distances of the face being challenged. Preliminary results show...
J K Carey, A F Bravery
Termite Field Tests of Various Timber Species Treated with permethrin using supercritical carbon dioxide
2005 - IRG/WP 05-10560
Termite field tests were conducted on permethrin-treated Eucalyptus obliqua heartwood, Pinus radiata sapwood and P. radiata LVL. The permethrin was impregnated using either supercritical carbon dioxide (scCO2) or light organic solvent preservative (LOSP) systems. Comparative permethrin retentions were most accurately achieved in P. radiata sapwood, where no difference between impregnation systems ...
A Qader, L J Cookson, J W Creffield, D Scown