Your search resulted in 768 documents. Displaying 25 entries per page.
Influences of the hydro-thermal treatment on physical properties of beech wood (Fagus orientalis)
2005 - IRG/WP 05-40303
Influences of the hydro-thermal treatment on physical properties of beech wood were studied. Wood specimens (2×2×2cm) were treated in two steps. At first step, samples were treated at 160,180 & 200ºC for 4, 5 & 6 hours. At second step, treated samples were cured based on their first step treatment temperatures (160,180 & 200ºC) for 16 hours. The treated samples were soaked in water...
B Mohebby, I Sanaei
Effects of heat treatment on modulus of elasticity of beech wood
2002 - IRG/WP 02-40222
Heat treatment is the oldest, simplest and cheapest method for reducing hygroscopicity of wood. The heat treatment protects wood against to biological organisms as well as giving
wood dimensional stabilization without damaging environment. The effects of heat treatment on modulus of elasticity (MOE) of beech wood (Fagus orientalis Lipsky) naturally grown and intensively used in forest products in...
S Yildiz, G Çolakoglu, Ü C Yildiz, E D Gezer, A Temiz
Basidiospore structure and germination of Serpula lacrymans and Coniophora puteana
1988 - IRG/WP 1340
Using a nuclear staining technique and fluorescence microscopy, the basidiospores of Serpula lacrymans were shown to be uninucleate whereas those of Coniophora puteana were binucleate. The germination rate of the Serpula lacrymans spores, which was considerably lower than that of Coniophora puteana, decreased further after storage or heat treatment. Transmission electron micrographs indicate that ...
B M Hegarty, U Schmitt
Heat inactivation of mould fungi on wood
1993 - IRG/WP 93-40012
Heat treatments have been successfully used for eradication of dry rot. The effect of heat treatments at 40, 50 and 60°C for various time intervals on the inactivation of Penicillium brevicompactum was determined. The effect of heat on ungerminated spores and spores "pregerminated" for 24 hours was evaluated by plating on malt-extract agar. Although most ungerminated spores were inactivated after...
J Bjurman
New experiences with Dry Rot in Danish buildings, heat treatment and viability tests
1989 - IRG/WP 1423
An increasing number of concealed dry rot attacks, especially in older multi-storey houses under renovation, have been detected during the last few years. A necessary consequence is a demand for cheaper methods of repair, compared to the standard method used in Denmark for many years otherwise severely attacked houses will by pulled down. A heat-treatment has been developed and tested in practice....
A P Koch, C Kjerulf-Jensen, B Madsen
Ammoniacal wood preservatives for use in non-pressure treatment of spruce and aspen poplar. Part 2
1984 - IRG/WP 3274
A series of thermal diffusion treatments were carried out on unseasoned white spruce (Picea glauca (Moench) Voss) lumber and air dry aspen poplar (Populus tremuloides Michx.) timbers using an ammoniacal copper arsenate wood preservative. Under the specific conditions described, certain charges of lumber met the present Canadian Standards Association Wood Preservation Committee's requireme...
C D Ralph, J K Shields
Biological resistance of steam-compressed wood pretreated with boric compounds
1999 - IRG/WP 99-30190
Wood compression under heating is aimed to enhance dimensional stability and surface hardness. Preservative treatment with an appropriate chemical is additionally required for the protection of wood against biological agents under hazardous service conditions. Boron pretreatment of compressed wood was targeted to a mutual benefit of increasing biological resistance of compressed wood as boron was ...
M K Yalinkilic, W Dwianto, Y Imamura, K Tsunoda, M Takahashi
The effect of heat treatment on the properties of spruce
1994 - IRG/WP 94-40032
The effect of high temperature treatment (above 150°C) on the wood quality is studied at the VTT. Improved dimensional stability, lower equilibrium moisture content and increased durability against biodeterioration is achieved, depending on the environmental factors. The biodeterioration resistance of spruce is improved due to changes in chemical composition and lower equilibrium moisture content...
H Viitanen, S Jämsä, L Paajanen, A J Nurmi, P Viitaniemi
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
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
Bending strength of heat-treated spruce and pine timber
2002 - IRG/WP 02-40242
Heat-treatment of spruce (Picea abies) and pine (Pinus sylvestris) beams (45 x 145 mm) gave a reduction in bending strength of approximately 50%. The bending stiffness (modulus of elasticity) only decreased by 3.5%. Tests were carried out according to EN 408. Another effect of the heat-treatment was increased variation in bending strength. The 5th percentile value of the bending strength, the so c...
C Bengtsson, J Jermer, F Brem
Treatment groups and remedies for CCA treated hardwood and softwood poles
1999 - IRG/WP 99-40142
Different hardwood and softwood species from Bangladesh and Bhutan was investigated regarding density, green fiber stress, natural durability of heartwood and CCA treated sapwood, CCA treatability grades, sapwood thickness, and kiln-drying properties for long term use as electric poles. These properties along with the past service records for nineteen years, separated ten heardwood and five softwo...
A K Lahiry
Environmental characterisation of retification process by-products (liquid and gaseous wastes)
2005 - IRG/WP 05-50224-10
In order to reduce environmental risks during the service life of the treated wood and to find new alternative developments on the durability of wood, some research and technology development have been made on thermal treatment. The retification process is one of these processes. The retification process induces chemical modification of the lignin and cellulosic components and modifies the intrins...
G Labat, E Bucket, S Legay, C Yriex, P Marchal, E Raphalen, M Vernois, R Guyonnet, H Besset, E Fredon), G Vilarem, L Rigal, C Raynaud
Durability of some alternatives to preservative treated wood
2004 - IRG/WP 04-30353
The environmental discussion in Sweden has lead to an increasing use of naturally durable domestic wood species and wood treated according to alternative methods for use above ground. A number of these alternatives have been tested according to field- and laboratory tests and compared to wood treated with preservatives for above ground use. Seven untreated wood species, four alternative wood treat...
M-L Edlund
Formosan Subterranean Termite Resistance to Heat Treatment of Scots Pine and Norway Spruce
2003 - IRG/WP 03-40264
New challenges to the durability of wood building materials have arisen in the U.S. The Formosan subterranean termite (Coptotermes formosanus Shiraki) now infests sizable portions of the U.S. south and their range is extending. Heat treatments offer a unique opportunity for wood-based composites because many of the process techniques already employ various thermal applications and could be easil...
W R Smith, A O Rapp, C R Welzbacher, J E Winandy
Blue Staining of Coated Modified and Unmodified Wood
2006 - IRG/WP 06-10589
We investigated resistance of unmodified, DMDHEU modified and oil heat treated uncoated and coated Scots pine wood against blue stain fungi. Both EN 152-1 and the reverse exposure tests showed excellent resistance of DMDHEU and especially of oil heat treated wood against blue staining. It is not needed to add any additional protective coating layers to prevent modified wood from staining. However,...
M Petric, M Pavlic, M Humar, M Tomažic
Identification of fungi colonising coated and modified wood exposed outdoors using sequencing and T-RFLP profiling
2006 - IRG/WP 06-20326
Wood decay and staining fungi are known to colonize coated and modified wood. Rapid and reliable ways of identifying fungi on coated and modified wood may improve diagnostics and product development. In this work nine fungi growing in painted wood panels exposed outdoors at a test field in Uppsala, Sweden, were identified using sequencing and T-RFLP (Terminal Restriction Fragment Length Polymorphi...
U Råberg, J Bijelovic, C J Land, S Bardage, N Terziev
High-energy multiple impact (HEMI)-test – Part 2: A mechanical test for the detection of fungal decay
2006 - IRG/WP 06-20339
The suitability of the high-energy multiple impact (HEMI)-test for detection of early fungal decay was examined. The HEMI – test characterizes the treatment quality of thermally modified wood by stressing the treated material by thousands of impacts of pounding steel balls. This method differentiates between heat treatment intensities, which are expressed by structural changes of the wood. Simil...
C R Welzbacher, C Brischke, A O Rapp
High-energy multiple impact (HEMI)-test – Part 1: A new tool for quality control of thermally modified timber
2006 - IRG/WP 06-20346
Thermal modification processes improve durability and dimensional stability of wood, but the strength properties, especially the dynamic ones, are compromised and need to be considered with respect to industrial quality control. Results from standard dynamic strength testing, such as impact bending tests, suffer from high variability, and therefore require a high number of replicates. To overcome ...
C Brischke, A O Rapp, C R Welzbacher
Heat treatment of less-valuable Nigerian-grown Ceiba pentandra wood for improved properties
2006 - IRG/WP 06-40332
The hardwood Ceiba pentandra locally known as “ araba “ in Nigeria is rarely used for structural and construction works due to its high dimensional instability, low strength and durability values. Samples (10 x 10 x 150mm) were removed from four green boards (25 x 200 x 3000mm) of this species originating from a natural forest stand in Nigeria and subjected to 2-hour heat treatment at 160°C a...
L Awoyemi
Improvement of Grevillea robusta durability using heat treatment
2006 - IRG/WP 06-40333
Heat treatment of Grevillea robusta was carried-out under inert conditions to improve its durability. Resistance of heat treated samples was evaluated by malt agar block tests after three months of exposure to several wood rotting fungi. Results showed that the fungal durability was greatly improved after treatment. There was a good correlation between fungal resistance and mass loss which is a fa...
F Mburu, S Dumarçay, F Huber, M Petrissans, P Gérardin
Wood plastic composites from modified wood; Part 1 - Conceptual idea, mechanical and physical properties
2006 - IRG/WP 06-40338
Wood plastic composites, WPCs, are rapidly taking shares from preservative treated wood on the decking market. However, the long term performance of the WPC products in this application is uncertain. Therefore, in an attempt to increase the long term performance and durability, the substitution of the unmodified wood component with modified wood has been studied in the work presented in this paper...
P Larsson Brelid, B K Segerholm, M Westin, M E P Wålinder
Assessment of the Envelope Effect of Three Hot Oil Treatments: Resistance to Decay by Coniophora puteana and Postia placenta
2006 - IRG/WP 06-40344
Timber of Corsican pine (Pinus nigra var. maritima) and Norway spruce (Picea abies) was treated in hot linseed oil, rapeseed oil and a proprietary resin derived from linseed oil. The samples were immersed in oil or resin under reduced pressure at temperatures of 180°C and 200°C. Very high uptakes of the oils or resin were recorded for pine, while spruce showed lower weight percent gains, below...
M J Spear, C A S Hill, S F Curling, D Jones, M D C Hale
Wood plastic composites from modified wood. Part 2 - Durability in laboratory decay tests
2006 - IRG/WP 06-40353
The decay resistance of wood plastic composites, WPCs, was tested according to modified versions of AWPA E10 (soil-block test) and ENV 807 (tests in three un-sterile soils, terrestrial microcosms, TMCs). The WPC materials were conically extruded profiles with 30% polypropylene content. The 70% wood content was untreated Scots pine sapwood, acetylated pine and heat treated Norway spruce, respective...
M Westin, P Larsson Brelid, M L Edlund, G Alfredsen
Natural Weathering of Coated Oil Heat Treated Wood
2007 - IRG/WP 07-30440
Oil heat-treated (thermally modified) pine wood was coated with 9 different types of solvent- or water-borne exterior finishes. The systems with modified wood substrate as well as unpainted and painted non-modified controls were exposed to weathering (EN 927-3) on two locations with sub-alpine and alpine climate. The influence of natural ageing on surface systems was evaluated after one year of ex...
M Petric, B Kricej, M Pavlic, A Rapp