Your search resulted in 372 documents. Displaying 25 entries per page.
The use of natural and synthetical tannins to improve the dimensional stability and durability of beechwood (Fagus sylvatica)
1993 - IRG/WP 93-30016
Synthetical tannins and natural extractives of oak, spruce and chestnut have been combined with different fungicides to make the wood more dimensionally stable and more durable. The anti-shrink-efficiency and the improvement of the durability of different synthetical and natural tannins have been evaluated. The results make clear, that an application of the mentioned agents for common use cannot b...
H Militz, W J Homan
Wood preservative potential of fractions of wood pyrolysis tar made from Japanese larch
1996 - IRG/WP 96-30102
Wood pyrolysis tar, which was discharged as a waste by-product in the production of charcoal from Japanese larch (Larix leptolepis), was separated into several fractions by solvent extraction using tetrahydrofuran, benzene and aqueous alkali. The fractions obtained were physico-chemically characterized and examined for wood preservative potential. This separation method compared favorably with fra...
T Suzuki, S Doi, M Yamakawa, K Yamamoto, T Watanabe, M Funaki
Assessment of untreated Papua New Guinea timbers against subterranean termites. Progress report 2
1993 - IRG/WP 93-10040
Eight species of Papua New Guinea wood including Kwila (Intsia palembanica), Taun (Pometia pinnata), Malas (Homalium foetidum), PNG Walnut (Dracontomelon dao), Calophyllum (Calophyllum sp.), Kamarere (Eucalyptus deglupta), PNG Beech (Nothofagus spp.) and White Cheesewood (Alstonia scholaris) were exposed groun contact for their natural durability against subterranean termites. Inspection after 42 ...
M Rokova, H C Konabe
Screening of modified linseed oils on their applicability in wood protection
2004 - IRG/WP 04-30346
In this study modified linseed oils, rape oil and three waxes were screened on their efficacy as wood protecting agents. By testing all products when impregnated with high retentions in Scots Pine sapwood on water repellence qualities, additionally an accelerated weathering test, drying quality, accelerated brown rot and blue stain test, an indication is formed of the capability of these products ...
A Treu, J Lückers, H Militz
Natural durability of larch heartwood against decay
1997 - IRG/WP 97-10201
Larch heartwood has been promoted in Sweden and in other European countries as an alternative to preservative treated timber. It has even beeen stated that larch heartwood is more durable than preservative treated timber. This paper presents a compilation of facts from scientific reports on the durability of larch heartwood. Some recent data from this department are also reported. All data suggest...
T Nilsson
Evaluation of the natural durability and ultrasonic method for decay detection of some european hardwood and softwood species
2004 - IRG/WP 04-10537
This paper presents the first part of an investigation on the natural durability of mixed plywood made of durable and non durable plies from the following selected timbers : Cedrus atlantica, Cupressus sempervirens, Castanea sativa, Populus sp. I 214 and Fagus sylvatica.
In order to carry out this study, the natural durability of the massive wood used to manufacture the plywood panels was asses...
F Faraji, M-F Thévenon, B Thibaut
Variation in natural durability of British grown Douglas fir ((Pseudotsuga menziesii (Mirb.) Franco). Part II. Effect of extractive contents and taxifolin
2002 - IRG/WP 02-10446
The previous paper (Part I: Effect of density and growth rate) described the variation in natural durability of 4 Douglas fir (DF) seed origins (Darrington, J. Landing, Naselle and Hawkinsville) in a pure culture decay test and fungal cellar test. The pure culture tests were performed against two brown rot fungi (Coniophora puteana and Postia placenta). In the fungal cellar test soft rot was the p...
S Akhter, M D C Hale
Natural resistance of twenty-five timber species to marine borer attack in Goa waters (India)
1992 - IRG/WP 92-4178
Natural durability of 25 species of Indian timbers has been discussed, based on data collected from test panels exposed in Goa waters (west coast of India. for a period of 7 months. All the timber species, except Cleistanthus collinus, were heavily destroyed within 7 months on account of the combined attack by Martesia striata (Linnaeus) and Lyrodus pedicellatus (Quatrefages). Cleistanthus collinu...
L N Santhakumaran, G Srimannarayana, K Nagaiah
Natural Durability studies and Changes in wood chemistry of some Ghanaian hardwoods during decay by white- and brown-rot fungi
2004 - IRG/WP 04-10542
The natural decay resistance of Esa (Celtis mildbraedii), Wawabima (Sterculia rhinopetela) and Dahoma (Piptadeniastrum africanum) obtained from Ghana was determined according to BS EN 113 (1997). Esa was found not durable to the white-rot, but very durable to the brown-rot; Wawabima was very durable to both white- and brown-rots; and Dahoma was durable to the white-rot, and very durable to the bro...
Zeen Huang, K Maher, S A Amartey
Differentiation of Scots pine heartwood and sapwood by near infrared spectroscopy
2003 - IRG/WP 03-10459
In Scandinavia Scots pine heartwood has, in recent years, gained popularity as material for external structures exposed to moderate risk of decay. As non-durable sapwood surrounds the heartwood in pine trunks it is of crucial importance to separate this wood from the heartwood during log processing into heartwood products. Heartwood and sapwood can be differentiated by visual evaluation of colour ...
P O Flæte, E Ystrøm Haartveit
The accelerated L-joint test method for determination of the out of ground natural durability
1998 - IRG/WP 98-20146
The accelerated L-joint test incorporates a moistening device and uses a close end water trap in an open joint connection with a laminated tenon member consisting of the perishable reference wood species scots pine sapwood and beech.
After one year of exposure it is possible to show a distinct identification of natural durability classes 4 and 5 against the more durable wood species. Both weight ...
J Van Acker, C Brauwers, M Stevens
Standardization of CCA treated 45 hardwood species grown in Bangladesh for REB crossarms
1995 - IRG/WP 95-20059
Researches on 45 hardwood species grown in Bangladesh regarding density, moduli of rupture (MOR), colour and treatability of sapwood and heartwood, seasoning property and natural durability of heartwood revealed that both sapwood and heartwood of 17 species could be full cell pressure treated with CCA at impregnation pressure of 14-18 kg/cm² and only sapwood of rest 28 species could be pressure t...
A K Lahiry
Comparison of Temporal Changes in Metal Leaching and Aquatic Toxicity from Wood Treated with CCA and Alternative Preservatives
2005 - IRG/WP 05-50236
This study compares the temporal variation of chemical leaching and aquatic toxicity of wood treated with chromated copper arsenate (CCA) and other copper-based wood preservatives (alkaline copper quaternary (ACQ), copper boron azole (CBA), copper citrate (CC) and copper dimethyldithiocarbamate (CDDC)). Treated wood blocks were leached for 21 days and the leachate collected was analyzed for prese...
B Dubey, T G Townsend, G Bitton, H M Solo-Gabriele
An aquaria test of the natural resistance against marine borers of some commercial timbers available in Australia
1996 - IRG/WP 96-10145
The natural resistance of the heartwood of 22 different timbers grown or commercially available in Australia was examined. Radiata pine sapwood both untreated, and treated with 5.4 kg/m³ CCA salt, was included for comparison. Small timber blocks were exposed for one year in tanks containing either Limnoria tripunctata or Lyrodus pedicellatus. Four softwood species tested were heavily attacked and...
L J Cookson
Comparison of various types of bait containers designed to aggregate large numbers of foraging subterranean termites from natural populations in below-ground mound colonies
1995 - IRG/WP 95-10116
At Walpeup in the semi-arid mallee country of north-west Victoria (350 km from Melbourne), there are several indigenous subterranean termite species, none of which build above-ground mound colonies but build their colonies below-ground and/or in trees. This paper describes a baiting experiment in which three types of bait containers were compared in their ability to aggregate large numbers of fora...
J R J French, B M Ahmed
Weathering trials on natural wood finishes in New Zealand
1986 - IRG/WP 3383
The weathering properties of various transparent and semi-transparent exterior finishes for New Zealand-grown radiata pine are currently being examined. After 12 to 16 months' weathering, unpigmented water repellents have failed to provide satisfactory protection from weathering under field test conditions. With the exception of two formulations, penetrating oil-based stains are already s...
D V Plackett, C M Chittenden
Biological and physical properties of phenolic-resin treated wood before and after natural weathering
1999 - IRG/WP 99-40132
Biological and physical properties of phenolic resin-treated particleboards, which were made from fast growing tress and agrowaste as raw materials, were evaluated before and after natural weathering in tropical climate. The particles were sprayed with a mixture of a low molecular weight phenol-formaldehyde resin (5.0, 7.5 and 10% loading) and the adhesive phenol resin (8% loading). Results with l...
S Yusuf, Y Sudiyani, H Kajita, Y Imamura, M Takahashi
Possible durability transfer from durable to non durable wood species. The study case of teak wood
2001 - IRG/WP 01-10392
Teakwood is well known for its excellent natural durability, mostly due to its high proportion of extracts. Amongst these extracts, quinones, and more precisely some naphtoquinones (such as lapachol) and anthraquinones (such as tectoquinone) appear to play a crucial role in the resistance to wood decay organisms. At a laboratory scale, sawdust from malaysian teak heartwood has been extracted under...
M-F Thévenon, C Roussel, J-P Haluk
The natural durability of five Indonesian timber species against marine borers - A field test in Indonesia
1981 - IRG/WP 474
This paper presents results of a natural durability field test using five species of Indonesian timbers against marine borers. An attempt is also made to assess any difference in durability between the lower and upper part of the trunks. Results of marine fungal identification, soft-rot assessment, and marine-borer assessment of CCA-treated test blocks will be reported in separate papers...
Suhirman, R A Eaton
The natural history of teredinid molluscs and other marine wood borers in Papua New Guinea
1975 - IRG/WP 410
The teredinids, commonly known as teredos or shipworms, are bivalve molluscs adapted to boring into wood. They are most closely related to the Family Pholadidae, or piddocks, which bore into mud, stone and coral. The teredinids have a relatively small, hemi-spherically shaped shell, the elongated body extending beyond the posterior end of the shell valves. The soft body, protected by the wood and ...
S M Rayner
Nondestructive assessment of biodegradation in southern pine sapwood exposed to attack by natural populations of decay fungi and subterranean termites
1994 - IRG/WP 94-20042
Field methods for evaluating decay resistance of experimentally treated materials lack a means for quantitative measurement of residual strength. Quantitative relationships between speed of impact-induced waves travelling parallel to the grain and residual compressive strength have been demonstrated in softwood attacked by brown rot-decay fungi, but the effects of termites have not been documented...
R C De Groot, R J Ross, W Nelson
Effects of the specimen position on fungal colonisation and wood decay by en 113 test fungi
1998 - IRG/WP 98-20136
For testing wood preservatives according to EN 113 it is common practice to plant the test blocks on neutral supports in order to prevent (1) a diffusion of chemicals into the agar medium and (2) an excessive moistening of the specimens. The procedure was employed in EN 350-1 for testing the natural durability of solid wood.
It turned out to be of problematic nature because of the individual requ...
G Kleist, M-T Lenz, R-D Peek
European standardization for wood preservation. Progress report 91-92
1992 - IRG/WP 92-2398
Since the IRG 22 conference in Kyoto, CEN/TC 38 Plenary met twice in relation with several working group meetings. 5 upon 6 of the interpretative documents have been prepared by adhoc groups of the Standing Committee for Construction within the scope of the 89/106/EEC directive on Construction Products. The expected requirements attached to wood preservation are both requirements 1) and 3): 1) mec...
R Hüe
Anti-fungal properties of pyrolytic oils derived from softwood bark
2000 - IRG/WP 00-30218
Thermal decomposition of balsam fir and white spruce mixed bark residues at 450°C and under vacuum (< 20 kPa abs.) results in high yields of pyroligneous liquors rich in phenolic content. This vacuum pyrolysis process has been scaled-up to a pyrolysis plant with a feed capacity of 3.5 t/h of softwood bark, which is the largest plant of this type in the world. The pyrolytic aqueous condensates ...
D Mourant, Dian-Qing Yang, Xiao Lu, C Roy
Blue stain in timber in service. Preliminary results of the IRG collaborative tests to compare natural and artificial weathering
1978 - IRG/WP 286
The collaborative programme was initiated at IRG Meetings in Wildhaus, 1976. The six collaborators were BAM (Berlin), Cuprinol Ltd (UK), EMPA (Switzerland), GORI (Denmark), PRL (UK) and Imperial College (UK). Experimental plans were finalised in December 1976 and panels treated by Cuprinol Ltd early in 1977. Natural weathering was carried out by BAM, Cuprinol, EMPA, GORI and PRL during April-Septe...
A F Bravery, D J Dickinson