Your search resulted in 3367 documents. Displaying 25 entries per page.
Increased biological durability differs for traditional wood preservation and new non-biocidal systems (NBS)
2000 - IRG/WP 00-20212
Wood preservation is a way to increase the biological durability of wood by the addition of chemical components with a biocidal effect. The effect of such treatment is clearly concentration dependent. At distinct levels of fungicide concentration fungi are killed or inhibited in their enzymatic functioning to provide nutrients. The toxic limits allow decision-makers to provide treating prescriptio...
J Van Acker, M Stevens
A comparison of the diffusion of boron from two types of solid preservative rods into the heartwood of 3 Eucalypt pole species
2000 - IRG/WP 00-30227
The ability of boron to diffuse from polyborate and boron/fluoride rods through the heartwood of three eucalypt pole species (blackbutt, red ironbark and spotted gum) was examined. The aim was simply to determine the effects of rod type, wood species and time on the longitudinal diffusion of boron in eucalypt heartwood. Rapid diffusion of boron from polyborate or boron/fluoride preservative rods o...
P J Beutel, P D Evans
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
A study of the rate of fixation of various chromium-containing preservatives
1991 - IRG/WP 3653
Denmark, and Scandinavia in general, has perhaps the widest range of approved industrial wood preservative types in the world. As an aid in setting realistic fixation periods, work was undertaken to investigate the rate of fixation of chromium in CCA salt, CCA oxide, CCP, CCB, CC and CCF formulations at summer and winter temperatures. The rate of fixation measured in terms of the concentration of ...
L B Sheard
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
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
Fungal decay of acrylate treated wood
2004 - IRG/WP 04-30357
Natural durability of wood species is variable. Chemical wood preservatives, such as biocides are necessary for extension of their service life. Many methods have been developed to increase the resistance of wood and wood products against wood-destroying organisms during the last years. The most frequently used methods are chemical and thermal modification of wood. In wood modification the basic c...
Z Tiralova, L Reinprecht
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
Modelling of copper emission fron treated wood leached according to NEN 7345 and ENV 1250.2
1996 - IRG/WP 96-20097
A series of water leaching experiments is carried out investigating pine and spruce treated and fixed using different copper-containing preservative solutions and process technologies. Water changes took place as prescribed in the Dutch standard NEN 7345 and the European test method ENV 1250.2, each of the leachates being chemically analysed for their copper content. Irrespective of the preservati...
G M F Van Eetvelde, S G L Michon, M Stevens
Control of wood biodeterioration by fungal metabolites
1992 - IRG/WP 92-1527
Treating wood with different conventional preservative chemicals for protection and economic utilisation is well known. Tough some of these chemicals are toxic to skin, their use as wood preservative is unavoidable as they should be toxic to biodeteriorating organisms also. Recent advances in chemistry of natural products enabled the use of wood extractives as biocidal compounds against biodeterio...
H S Ananthapadmanabha, H C Nagaveni, V V Srinivasan
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
Pollution in wood preservation - Aspects and problems
1973 - IRG/WP 55
In the field of wood preservation too, pollution problems have to be considered. They originate with the wood preservatives used. The extent of pollution differs widely with the type of preservative and the treatment process used. Per unit of impregnated timber, pollution will be lower if treatment is performed in treating plants than in distributed places. It will be highest for the old type Bouc...
H Willeitner
A review of the implementation of results-based standards for preservative treated timber
1999 - IRG/WP 99-20156
European standards for the specification of preservative treated timber are written in terms of the results achieved in the commodity by the treatment process. This is described in terms of penetration and retention of preservative. Results from a study on the commercial application of this approach in the UK show the difficulties associated with applying the new European standards; particularly w...
E D Suttie, A S Hughes, R J Orsler