Your search resulted in 3568 documents. Displaying 25 entries per page.
The importance of blue stain attack for the colonization by wood-rotting fungi of wood not in contact with the ground
1988 - IRG/WP 1349
When used in constructions not in contact with the ground, wood has been shown often to proceed from blue stain to moulds. The appearance of wood rotting fungi is normally delayed. Solid wood artificially inoculated with the blue stain fungus Pullularia pullulans was shown to permit germination of Pycnoporus cinnabarinus basidiospores. This was demonstrated by the use of an indirect and a direct b...
J Bjurman
Protection and efficient utilization of plantation grown lesser-known timbers of arid region in India - Acacia tortilis, Prosopis juliflora and Prosopis cineraria
2005 - IRG/WP 05-40321
The plantation-grown timbers are highly susceptible to insects/pests, borers and wood rot fungus. Wood preservatives copper chrome arsenic (CCA) 2% and chloropyriphos 2% solution treated under pressure on three plantation grown timber species viz. Acacia tortilis, Prosopis juliflora and Prosopis cineraria have shown encouraging results in enhancement of shelf life by protection of wood against woo...
S H Jain, H Kumar, R Arya, R L Srivastava
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
The wood preservation industry in Kenya
1997 - IRG/WP 97-30157
Like in many other tropical and sub-tropical countries, the necessity to protect wood using wood preserving chemicals was not found necessary in Kenya because of abundant supplies of naturally durable hardwoods. That situation changed as a result of depletion of natural hardwood forests and replacement by fast growing non-durable exotic species and the appearance of new, more lucrative markets for...
R Venkatasamy
Preliminary observations on tributyltin treated Scots pine sapwood using 119Sn (Mössbauer and NMR) spectroscopic techniques
1984 - IRG/WP 3312
119mSn Mössbauer data are presented for bis(tributyltin) oxide, tributyltin ethanesulphonate, bis(tributyltin) carbonate and tris(tributyltin) phosphate, both in the pure form and in Scots pine sapwood. The structures proposed for these compounds, in the solid state, are supported by 119Sn nuclear magnetic resonance spectroscopy.
R Hill
A review of the efficacy and uses of deltamethrin for wood preservation
1996 - IRG/WP 96-30105
The synthetic pyrethroid deltamethrin, is one of the most active insecticides available for protecting and curing wood from attack by beetles and termites. Freshly felled trees can be protected against bark beetles by spraying to run off with a 0.025% Al solution (K-Otek EC25) with negligible leaching. Alternatively, sawn timber may be dipped in a 0.0125% Al solution for short to medium term prote...
A J Adams, J L Lindars
Modification of solid wood: research and practical potential
1997 - IRG/WP 97-40098
The polymeric structure of the wooden cellwall mainly consists cellulose, hemicellulose and lignin. The most reactive sites on these components are the hydroxyl groups. The cellwall polymers (and its reactive hydroxyl groups) are responsible for most physical and chemical properties of wood. By changing the basic chemistry of the cellwall polymers, it is possible to change different undesirable at...
H Militz, E P J Beckers, W J Homan
Performance of water-borne pressure treated fence posts - A practical application of the new Canadian field test data base
1988 - IRG/WP 2305
50 years of test plot data acquisition have been recently set up as a computerized database. The new database which contains information on the service life of a great number of non durable Eastern Canadian wood species treated with various preservatives and many application processes is presented. As an example for its use, a summary of the performance of fence posts treated with waterborne prese...
E E Doyle, R Dubois, J P Hösli
Categories in wood preservation hazard, risk, and use
1994 - IRG/WP 94-20048
In various countries hazard-, risk-, or use-categories have been established. The different terms seem to be only a sophisticated language problem, but they are rather a basic principle of the philosophy of wood preservation which is going to obtain importance with respect to the low reputation of chemical wood preservatives in an increasing number of countries. Whilst hazard signifies the fact th...
H Willeitner
Dimensational stabilisation of wood
1981 - IRG/WP 3171
A review is given of the studies on the dimensional stabilisation of wood which have been carried out in the laboratory 5.14 "Wood Technology" since 1967. All stabilisation methods known have first been compiled from the available literature. Practical studies were then started. Wood was treated with monomers (styrene, methyl metacrylate, isocyanate), formaldehyde, tannin and sugar. Despite a sati...
A Burmester
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
In vivo growth study on two gymnosperms and four angiosperms for REB wood poles
1998 - IRG/WP 98-10246
Revealed that the highest growth rates and pole yield in two plantation sites in Bangladesh are significant with 2.06 cm/y in diameter, 0.97 m/y in height and 90% pole yield within 19y in Pinus caribaea; 1.96 cm/y, 0.91 m/y and 100% pole yield within 15y in Xylia dolabriformis; 1.88 cm/y, 0.91 m/y and 22% pole yield within 13y in Dipterocarpus turbinatus; 1.64 cm/y, 0.82 m/y and 28.75% pole within...
A K Lahiry
Laboratory versus field tests for evaluating wood preservatives: A scientific view
1995 - IRG/WP 95-20076
The relative merits of field tests versus laboratory tests for evaluating wood preservatives are discussed. Many of the problems involved in interpretation of the results are similar for both types of test. One major problem is to select field sites or laboratory tests that are representative for the practical use of treated timber in ground contact. Decay tests with treated wood in unsterile soil...
T Nilsson, M-L Edlund
Northern oak wood and its damages in Iran
1988 - IRG/WP 1377
The Northern oak species of Iran designated Quercus castaneaefolia C.A.M. is distributed widely in caspian littoral. In natural conditions (healthy) has favourable quality and it is used mostly in rural construtions, sleepers, parquets, cross arms for electric and communication poles, it is used also indoor and window construction, benches and finally veneer. This wood in the case of sleepers and ...
D Parsapajouh, P Niloufari
Performance criteria for approving new wood preservatives for ground contact
1994 - IRG/WP 94-20021
Protocols for testing novel formulations prior to approval or registration as wood preservatives are being developed in a number of countries, e.g. Australia, New Zealand, USA. One aspect which must be addressed is the effectiveness in tests relative to that of currently approved formulations which would be acceptable to approving authorities. It is assumed that natural exposure testing is a prere...
M E Hedley
Investigation of temperature effect on fixation of Celcure preservative (ACC) in Hornbeam (Carpinus betulus I)
2003 - IRG/WP 03-30304
In this research, the fixation speed of Celcure 2 % (ACC) preservative salt, under temperature of 30 ºC, 40 ºC and 50 ºC on intact wood specimens of hornbeam was investigated. For this purpose, blocks of wood with 2Í 2 Í2 cm dimensions of hornbeam were prepared and saturated with 2% ACC concentration by full-cell process. The specimens were put in three incubators at the above-mentioned temperatures. For measuring the percentage of fixation through time, the specimens were extracted by using hydraulic pressure equipment, under 70 Mpa pressure. The PH of extraction was measured with the method of Diphenyl Carbazid and by using spectrophotometer. This measurement was done continuously and the amount of 6-valence chromium concentration present in the extract was compared with the amount of chromium concentration in the primary solution and then the percentage of fixation was calculated.
The results showed that the decrease in 6-valence chromium is accompanied with increase of PH, this due to absorption of positive hydrogen ion by 6-valence chromium for reduction to 3-valence chromium and also ion –exchange of active components with wood during the primary phase of fixation. Also, the time necessary for reaching complete fixation in intact wood in the fixation temperature conditions of 30, 40, 50 ºC were 98, 52, 24 hours, respectively. In general, the results showed that temperature has effective role accelerating of fixation process.
R Imani, R E Majdar, A Karimi
Variation in biological performance of CCA caised by preservative application method
1996 - IRG/WP 96-40072
A series of laboratory studies to investigate the influence of treatment application method on CCA performance in Cosican pine has been completed. Biological decay tests, such as serial exposures, were used to induce decay in wood at preservative retentions of up to 10 kg/m³ CCA salts. Significant differences in performance of the preservative against either brown, white or soft rot decay fungi w...
P R Newman, R J Murphy
Laser incising of spruce lumber for improved preservative penetration
1991 - IRG/WP 3646
Red spruce heartwood specimens were incised using a range of laser beam power levels and pulse durations. The penetration of CCA through these holes into the wood was monitored after pressure treatment. In addition, green and dried spruce samples were incised using two patterns with incision densities of either 16.1 holes/in² or 21.3 holes/in². Following CCA pressure treatment the samples were t...
B Goodell, F A Kamke, Jing Liu
A new preservative - A double-edged sword
1990 - IRG/WP 3573
Increasing environmental pressures on the use of pesticides throughout the world will impact more on the use of all wood preservatives. In particular the use of traditional wood preservatives and methods of application are under close scrutiny. The industry is responding to the challenge of developing alternative products and systems but faces great problems due to the excellent performance and sa...
M Connell, J A Cornfield, G R Williams
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
Towards a unified international hazard class system
1996 - IRG/WP 96-20081
Working party 2.5 on International Standardisation has set the development of a unified hazard class system as a short-term objective. This document is intended to stimulate the discussion required to work towards such a system. Two possible approaches are discussed, the compromise approach and the development of a basic system from first principles. For the second approach, the factors impacting ...
P I Morris
Proposal for a method aiming at the quantification of the impact of wood extraction in Life Cycle Assessment
1998 - IRG/WP 98-50113
Life Cycle Assessment has been accepted as an instrument for the assessment of the environmental impact of products. Characterisation factors for impact assessment of emissions from products have been established. To date no characterisation factor exists for the extraction of biotic resources, for example wood. Since the main disadvantage of using wood as a material lies in the extraction of reso...
P Esser, E Van der Voet
Exterior wood stains
1979 - IRG/WP 3136
The use of semi-transparent exterior wood stains has grown remarkably since their development during the 1960s. This can be partly attributed to their offering a break with tradition at a time when it was being recognised that changes in the quality of timber and how it was used demanded different methods of exterior wood finishing. Information is already available on the characteristics and uses ...
E R Miller
Effects of steaming heat treatment of wood on the stimulation of termite feeding
1997 - IRG/WP 97-10212
At the 26th IRG conference, we reported that steamed Japanese larch heartwood samples were suffered a serious attack by subterranean termite, Coptotermes formosanus both in choice and no-choice feeding tests. This is possibly caused by the yield of termites stimulants in the wood samples resulting from the steaming process. Since the steaming heat treatment has often been applied to other several ...
S Doi, Y Kurimoto, M Takahashi, T Yoshimura
Inter-laboratory comparison of assessment methods for wood preservatives against subterranean termites: Determination of protection threshold limits for CCA
1999 - IRG/WP 99-10317
In 1996, several institutes conducted laboratory bioassays on the efficacy of unleached Pinus radiata specimens treated with copper-chromium-arsenic (CCA) and copper naphthenate (Cu Naph) at retentions of 0.5, 1.0, 2.0 and 4.0 kg/m3 (total salt for CCA; elemental copper for Cu Naph) against a range of species of subterranean termites (IRG/WP/96-10174). Each participant employed the standard test m...
J W Creffield, M Lenz