Your search resulted in 154 documents. Displaying 25 entries per page.
A new vacuum/pressure plant system
1988 - IRG/WP 3479
In the subtropical regions, the problem of wood supplying becomes more and more difficult to be solved. In that context, the Centre Technique Forestier Tropical had paid a particular attention to the valorization of products issued from plantations in dry zones of Africa. In these plantations, the products of clearings can be used as fencing, stakes or for traditional construction. However in thes...
C Dalois, R Schwartz, G R Y Déon
Permeability measurements on surface layers for detecting wood with abnormally high permeability
1988 - IRG/WP 2298
Wet storage of timber during the warm period of the year may lead to an increased permeability of the wood, an undesirable phenomenon for several wood industries and also for many end-uses. Neither before nor after drying, such wood with "wet storage damage" can be visually distinguished from wood with a normal permeability. A non-destructive method for inspecting the permeability of surface layer...
J B Boutelje, G Hägglund
Suppression of termite feeding by Sudan red 7B
1988 - IRG/WP 1344
Groups of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were fed for 14 days on wood shavings soaked in acetone solutions of one of three concentrations (0, 0.5, or 1%) of the dye, Sudan Red 7B. Groups of marked or unmarked termites were then placed in containers and allowed to feed on undyed wood for 21 days. Dyed termites had lower wood feeding rate, survivorship, and number...
K S Delaplane, L A Bourg, J P La Fage
Co-operative tests concerning the influence of solvent and drying method on the toxic limit of wood preservatives against Coniophora cerebella
1972 - IRG/WP 216
In the working group II of the IRG it was agreed that more knowledge was necessary concerning the influence of the solvent on the toxic limit of organic solvent types of wood preservatives against Basidiomycetes. A test program was drawn up and after discussion in the mentioned working group the final program was accepted by the co-operating institutes in 1969. In the test program two fungicides, ...
T Hof
Pretreatment decay in poles of Pinus sylvestris
1987 - IRG/WP 1329
Storage damage by blue stain and decay in poles before impregnation has been increasingly observed during recent years and there have been reports that salt-impregnated poles today are of lower quality because of incipient decay being increasingly common. The attacks may have started at the time of cutting and then continued during the period of seasoning at the plant, which could be as long as tw...
H Lundström, M-L Edlund
Redistribution of boric acid in radiata pine during drying after preservative treatment
1993 - IRG/WP 93-40010
Samples of 100 x 50 mm² radiata pine were processed with a variety of options to produce dry, boron-treated wood. Concentrations of boric acid in the central one-ninth and in the whole of the wood cross-sections were determined by chemical analysis and compared. Diffusion treated material was dried by air, conventional kiln (70/60°C), or high temperature kiln (120/70°C). Four different predryin...
A J Bergervoet, D R Page, J A Drysdale
Penetration of oil-borne preservatives in American elm
1975 - IRG/WP 355
Pressure treatment of elm posts and cants by Rueping schedules resulted in erratic penetration. Instead of the expected gradual decrease in retention from surface inward in posts, inner zones frequently contained more preservative than the surface quarter inch. Heartwood was found penetrated when sapwood was not. There were numerous skips in treated zones. The prevalence and possible causes were i...
E A Behr
The control and pretreatment decay in air seasoning Scots and Corsican pine poles in England
1990 - IRG/WP 1451
Previous work clearly showed that air-seasoned, British grown Scots and Corsican pine poles are subject to serious pretreatment decay. In order to control these infections a range of pretreatments are currently being investigated. One series of treatments is designed not only to control decay but also allow the development of mould and stain fungi in order to achieve the desired increases in poros...
D J Dickinson, A R Zahora, A P Dodson
The effects of accelerated drying of green Pinus radiata on its attractiveness to Anobium punctatum as an egg-laying site
1984 - IRG/WP 1199
The methods and results are given for a series of experiments in drying Pinus radiata sapwood under a variety of conditions, then exposing the material to Anobium punctatum egg-laying. The results showed very clearly that the attractiveness of the wood to gravid females was drastically reduced when dried from green at temperatures much above 35°C. Both simple oven drying and steam kilning produce...
D J Cross
A comparison analysis of eight strains of Serpula lacrymans (Schum. ex Fr.) S.F. Gray
1991 - IRG/WP 2362
Investigations were previously carried out to compare eight strains of Serpula lacrymans (Schum. ex Fr.) S.F. Gray (some used in various countries as standard test strains): FPRL 12C (England), FPRL 12E (Germany), Warsaw III (Poland), HFP 7802 (Japan), DFP 16508, 16509, 16521 and 16522 (Australia). Studies included growth rate and dry mass of mycelium, decay capacity, reduction of compression stre...
J Wazny, J D Thornton
Comparison of bluestain fungi growing in vitro and in vivo
1996 - IRG/WP 96-10149
Both moulds and bluestain fungi cause serious economic losses for forestry and timber processing industries and much research is aimed at finding environmentally and economically acceptable methods of control. It is especially important to study the growth of these fungi in freshly cut wood, which has been unaltered by drying or sterilisation, and which therefore resembles the substratum they woul...
A Uzunovic, J F Webber, D J Dickinson
Copper fixation in ACQ-D treated Chinese fir at various temperature and relative humidity conditions
2007 - IRG/WP 07-30436
In this study, the effect of different conditions of temperature, relative humidity, and duration of post-treatments on accelerating copper fixation in ACQ-D treated Chinese fir wood blocks was investigated. The conditions include the combination of three temperatures (21, 50, and 70?) and two relative humidity levels (20% and 80%), also include four temperatures (50, 70, 90, and 110?) without con...
Jinzhen Cao, Lili Yu
A preliminary note on the role of moisture absorption rate in durability assessment
2008 - IRG/WP 08-20383
The rate of moisture uptake was studied in 15 wood species using vermiculite at varying moisture levels as the exposure medium. As might be expected, moisture uptake varied widely among the species studied. While some of the more durable wood species were also resistant to moisture uptake, this was not always true. The results are discussed in relation to performance in under varying environmenta...
J J Morrell, L P Francis
Primary Study on Compressed Preservative-treated Wood (CPW) for Outdoor Applications
2008 - IRG/WP 08-40412
In this study, the compressed wood samples pre-treated with hot water bath or water spraying were immersed in the ammoniacal copper quat –type D (ACQ-D) preservative solution to get compressed preservative-treated wood (CPW). The liquid absorption and the recovery rate of compression deformation of the compressed wood was determined, as well as the surface hardness, the distribution of density a...
Jinzhen Cao, Jia Mao
Emission Rates of Active Substances from Preserved Wood in Use Class 3
2008 - IRG/WP 08-50256
The evaluation of an active substance or a biocidal product under the Biocidal Products Directive (BPD) requires that an environmental risk assessment is carried out. The risk assessment for wood preservatives includes scenarios for preserved wood (e.g. cladding on a house), in which the
predicted environmental concentration (PEC) in soil is calculated, using an emission rate for the active subs...
E F Baines
To decay or not to decay: An accelerated field test of the validity of the Scheffer index
2008 - IRG/WP 08-20392
The Scheffer Index was introduced in 1971 to predict the relative decay hazard of untreated wood exposed above-ground. Precipitation and temperature parameters are used in the calculation. A higher Scheffer Index value implies a greater risk of decay. An accelerated 18-month study using seven field sites with Scheffer Indices ranging from 35 to 400 and two wood types (Populus tremuloides and Pi...
G M Larkin, P E Laks
Dimensional Stability of Nine Tropical Hardwoods from Cameroon
2009 - IRG/WP 09-10687
This study investigated the swelling behavior, rate of swelling and dimensional stability of nine tropical hardwood species from Cameroon, namely ayous (T. scleroxylon), bilinga (N. diderrichii), bubinga (G. tessmannii), iroko (C. excelsa), Makore (M. heckelii), moabi (B. toxisperma), movingui (D. benthamianus), teak (T. grandis) and zingana (M. brazzavillensis). Continuous swelling was monitored ...
S R Shukla, D P Kamdem
Assessment of decay risk of airborne wood-decay fungi
2012 - IRG/WP 12-10787
The decay risk of airborne wood-decay fungi was investigated by using an air sampler. Japanese cedar disks measuring about 8 cm in diameter and 3 mm in thickness with moisture content at about 100 % were placed in a “BIOSAMP” air sampler and exposed to 1000 liters of air. Air sampling was carried out from June to September at the same sampling site in Tsukuba, Japan. The exposed disks were the...
I Momohara, Y Ota, K Sotome, T Nishimura
Differential response of wood to dry air thermal treatment (DATT) and soy oil thermal treatment (SOTT)
2009 - IRG/WP 09-40446
Thermal treatment is an alternative to chemical modification method which has been used to some extent in improving timber quality. In order to get the maximum benefits possible without compromising the various end-use quality requirements of timber, several possibilities have been and are still being investigated in relation to this technique. Clear wood samples (19 x 19 x 150mm) of kiln-dried re...
L Awoyemi
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Adsorption of ACQ components in wood
2010 - IRG/WP 10-30522
To investigate the chemical adsorption capacity of copper-monoethanolamine (Cu-Mea) components on wood, the Na+ cation exchange capacity (CEC) of red pine (Pinus resinosa Ait.) was determined and compared to the adsorption capacity of free Mea and Cu-Mea complexes. The CEC increased with increasing pH. Free Mea adsorption as a function of pH followed the sodium adsorption curve except at pH over 9...
Myung Jae Lee, P Cooper
Ecological methods and products for wood protection used for restoration and conservation of built heritage cultural assets to increase natural durability and duration of exposure in open air museums
2010 - IRG/WP 10-40506
Wood is a perishable material, hygroscopic and fuel, which cause attention to selecting the wood species that is going to be exhibited in relation to humidity and soil. With variable depending on its humidity and moisture from the atmosphere or soil, wood is a good living environment for fungi and insects, but suffer biodegradation processes and dimensional changes. Observations over time on wood ...
M Pruna, D Purice, D Dumitru Copacean
Influence of Copper Preservative Type on Earlywood and Latewood Distribution of Copper in Treated Wood
2010 - IRG/WP 10-40507
Some of the new water based copper containing wood preservative systems use particulate “micronized” copper as the primary biocide instead of the more traditional soluble amine copper based systems. Studies were conducted to investigate how this difference in the type of copper system might impact both initial and post drying distribution of the preservatives in wood. Of specific interest wa...
A Zahora
Kinetic Water Vapour Sorption of Sitka Spruce at Variable Temperature Using the Parallel Exponential Kinetics Model
2010 - IRG/WP 10-40512
In this study the water vapour sorption of Sitka spruce (Picea sitchensis (Bongard) Carr.) was measured using a Dynamic Vapour Sorption (DVS) apparatus and then analysed using the parallel exponential kinetics (PEK) model. The water vapour sorption rate of wood quickly increased when the relative humidity was changed. With the elapse of time, the sorption rate gradually decreased within any specif...
Yanjun Xie, C Hill
Methods of field data evaluation - time versus reliability
2011 - IRG/WP 11-20466
Field testing of wood and wood-based products is so far the most reliable way to get information on performance with respect to durability and expected service life. However, field trials are extremely time and cost consuming. The main objective of the present study was to investigate possible correlations between early stages of decay, preferably during the first 5 years, and the actual service l...
P Larsson Brelid, C Brischke, A O Rapp, M Hansson, M Westin, J Jermer, A Pilgård