Your search resulted in 967 documents. Displaying 25 entries per page.
Chemical treatment of ten Amazonian timber species of low natural durability
1991 - IRG/WP 3640
The objective of this work was to evaluate the performance of 10 amazonian wood species of low natural durability, to treatment with CCA preservative (2% concentration): it was concluded that all species studied are easily treated with this preservative. The sapwood showed high absorption and total penetration. The heartwood is relatively easy to preserve, exception to Parkia nitidae (Fava), Quale...
C S Neta, B F Vianez
Assessment of untreated Papua New Guinea timbers against subterranean termites. Final report
1993 - IRG/WP 93-10041
Four years after the exposure of eight timber species of varying density against subterranean termites in a field trial, Kwila was still generally sound while Taun, Malas and PNG Walnut were beginning to be attacked slightly to moderately. Calophyllum, Kamarere, PNG Beech and White Cheesewood were severely attacked and failed. Results after the period of exposure shows that Kwila rates highly as t...
H C Konabe, M Rokova
Laboratory tests on the natural durability of timber methods and problems
1984 - IRG/WP 2217
In literature a large variety of test methods is mentioned to examine the natural resistance of timber against fungal attack. This concerns the kind of sampling as well as the test procedure, the test fungi, the duration of test, and the classification of the resistance according to the test results. These variations, however, are of great influence on the test result. Long term exposure will lead...
H Willeitner
The comparative resistance to fungi of the wood munika (Pinus heldreichii Christ.), fir (Abies alba Mill.) and spruce (Picea excelsa Poir.) compared with Pinus sylvestris L. and some physical and mechanical characteristics of munika
1981 - IRG/WP 1129
The munika (Pinus heldreichii Christ.) is situated primarily in the Balkans, and partially in the south of the Apenine peninsula. As an endemic species, with a very little annual increment, it has not been used enough as a timber for mechanical conversion up till now, although the oldest trees can grow to 27 m in height, with a diameter at breast height of about 60 cm. According to data of many Ba...
M Petrovic, M Miric
Notes on a wood preservation industry in Medan, North Sumatera, Indonesia
1987 - IRG/WP 3405
This paper deals with a descriptive account on the development of a wood preservation industry in Medan, North Sumatera (Indonesia). The industry was established in 1974 when the State Owned Electicity Corporation decided to use wooden power poles for their distribution network in North Sumatera province. However, the use of wooden power poles was discontinued in 1981, so as the preservation indus...
N Supriana, A Murad
Natural durability of Norwegian wood species for above ground applications – Project presentation and preliminary results
2006 - IRG/WP 06-10594
In Norway exterior wood structures have traditionally nearly exclusively been made of treated and untreated Norway spruce (Picea abies (L.) Karst) and Scots pine (Pinus sylvestris L.). In recent years there has been a tendency that other tree species, like various domestic hardwoods and imported species have been used in exterior above ground applications, often unfinished. For several wood speci...
P O Flæte, G Alfredsen, F G Evans
Durability of heat-treated wood
1999 - IRG/WP 99-40145
Heat-treated wood from the French process were laboratory tested against decay using agar block test and a modified soil block test. Water absorption, bending strength, lignin content and acid number were also determined to evaluate the effect of heat treatment. Heat treated samples exhibit a higher lignin content and a lower acid number compared to untreated control indicating the degradation of ...
D P Kamdem, A Pizzi, R Guyonnet, A Jermannaud
A dynamic approach to assess the modulus of elasticity in wood decay testing
1998 - IRG/WP 98-20139
In this study, the changes in elastic behaviour and mass losses of different hardwood and softwood species exposed to decay in a laboratory soil tests were assessed. Wood decay was monitored using different assessment methods, namely: mass loss and changes in elastic behaviours (MOE) determination. Elastic changes were determined by static and dynamic methods, for the latter, acoustic technique wa...
L Machek, H Militz, R Sierra-Alvarez
Wood Preservation in the United Kingdom
1979 - IRG/WP 385
This is only the first of several reports in English currently being prepared about wood preservation in Europe. The report deals with the extent of industrial impregnation and the number of impregnation plants in use today in Great Britain. Timbers which are treated for various end uses and their life expectancies are discussed. The market for wood preservatives, the size of the motorway fencing ...
R Cockcroft
The effect of water storage on the cell-structure of Sitka spruce (Picea sitchensis) with reference to its permeability and preservation
1970 - IRG/WP III 3A
Commercial treatment trials with full sized transmission poles have shown that water storage considerably improves the permeability of Sitka and Norway spruce. These results were confirmed by laboratory measurements which showed that in the sapwood of ponded Sitka spruce there is a vast improvement in permeability in all three grain directions. Heartwood permeability does not seem to be affected t...
J A Dunleavy, A J McQuire
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 1: Optimisation of the extraction conditions
2000 - IRG/WP 00-30238
As the first phase of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, several solvents and extraction methods were evaluated, initially in the laboratory and then at pilot industrial scale. Extracts were compared by crude total dissolved solids content, by chemical analysis using GC-MS and LC-MS, and by laboratory...
M J Kennedy, Hui Jiang, L M Stephens
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 4: Analysis of extracts and treated wood for active components
2000 - IRG/WP 00-20215
In order to facilitate the commercial implementation of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, it has been essential to develop analytical methodology for the important bioactive components of the heartwood extract. This methodology will be used 1) to standardise the activity of successive production batc...
Hui Jiang, M J Kennedy, L M Stephens
Evaluating the resistance of wood-based panel products to fungal attack
1995 - IRG/WP 95-20071
At present there is considerable disagreement among national research institutes within Europe and panel product manufacturers on the most appropriate method of testing and indeed the need for specific biological durability testing. This paper seeks to place before a broader international audience, the issues related to development of a European standard for evaluating the resistance to fungal dec...
R G Lea, R W Berry
Chromium in wood preservation: Health and environmental aspects
1978 - IRG/WP 3120
The majority of water-borne salts in current use contain hexavalent chromium, usually as dichromate or chromium trioxide. In about 1913 it was suggested that chromates, phosphates or borates could be added to the sodium fluoride and dinitrophenol mixtures then in use in order to inhibit corrosion. Dichromates were found to be most suitable and the resulting mixture known as Thriolith and later Tri...
T R G Cox, B A Richardson
Wood preservation in Yugoslavia
1984 - IRG/WP 3319
This report, which is one in a series written by some of the most eminent experts in wood preservation in the world, is meant to serve as a practical guide to all those, both in Yugoslavia and in other countries, who wish to collaborate in the field of wood preservation production, wood preservation treatments and in the development and research work necessary in this subject. The report offers th...
N Vidovic, D Murko, R Cockcroft
Utilization of coconut timber from north Sulawesi, Indonesia. Part 1: Durability
1994 - IRG/WP 94-30044
Coconut timber from non-productive plantations is a byproduct of an agricultural crop and, by the same token, constitutes a renewable resource which may serve as a complement to or, at least in part, as a substitute for traditional timbers in local markets. Its more extensive utilization is expected to contribute to the conservation of tropical rain forests. Export of coconut timber and/or wood pr...
R-D Peek
Comparative natural resistance of eighty-two timber species to damage by marine borers at Goa (India)
1996 - IRG/WP 96-10139
Natural bioresistance of eighty-two species of Indian timbers to attack by marine wood-borers has been presented based on data collected from test panels exposed in Goa waters (west coast of India) for periods ranging from five to thirteen months. All the timber species, except Artocarpus gomeziana and Pterocarpus santalinus, were completely destroyed within a short period of three to six months. ...
L N Santhakumaran
A study of poplar LVL durability improvement:
1999 - IRG/WP 99-40148
The aim of this study was to optimise the durability of LVL panels by adding boron during the gluing process. Poplar veneers (2,6 mm thickness ) were selected by ISORY a French company . Two types of glue were tested : Phenol resorcine and Melamine Urea Formaldehyde. Each of them was mixed with various concentrations of borax (for the first one) and Boric acid(for the second one). Mechanical prope...
B Charrier, V Bridaux, N Fauroux, F Charrier
Status of wood preservation industry in India
2005 - IRG/WP 05-30388
The paper traces the history of wood preservation industry in India, listing various mile stones for creation of treating capacity. The preservation industry developed with the development of rail road system on the line of most other developed countries. The most popular wood preservatives are CCA, CCB, ACC, Creosote and recently LOSP have also appeared in the market. The major users of CCA is th...
S Kumar
The difficult choice of the preservation industry when changing to more environmentally acceptable products
2000 - IRG/WP 00-50156
Until recent years the preservation industry in Norway had no problems with the environmental authorities. However, during the last three years the pressure has increased, and the authorities' solution to restrict hazardous chemicals is to introduce green (environmental) taxes for the products containing these chemicals, and also for the pressure-treated wood. The preservation industry ac...
F G Evans
Tributyltin compounds in wood preservation: Health and safety aspects
1986 - IRG/WP 3396
The toxicity of organotin compounds of the general formula RnSnX(4-n) depends strongly on the type of organic substituent R and on the degree of substitution n. The residues X, not bound through a tin-carbon bond, are however of much smaller influence. Furthermore, there is evidence that hydrolysis of tributyltin esters will occur under environmental as well as under physiological conditions to TB...
H Schweinfurth, P Günzel, H A B Landsiedel, R Lang, R Reimann, C Schöbel, F Siegmund
Influence of carboxylic acids on LEACHING of copper amine based preservatives
2005 - IRG/WP 05-30365
The importance of chromium free preservatives is increasing. Leaching of copper from wood preserved with such solutions is still higher compared to leaching from wood impregnated with copper chromium ones. In order to decrease leaching, different carboxylic acids (octanoic, 2-etilheksanoic, decanoic) were added to copper/amine/boron aqueous solutions. Experiment of leaching of copper from Norway s...
M Humar, P Kalan, F Pohleven
Role of wood preservation in bioconservation and protection of environment
1997 - IRG/WP 97-50082
In order to meet a revolutionary task of bioconservation and protection of environment through preservation of less important and nondurable timbers from tropical zones, 170 timber species from Bangladesh were screened. Air-dried (12% MC) 170 different species of timbers, full cell pressure impregnated with 5% CCB solution revealed satisfactory treatability of all timbers for long-term indoor uses...
A K Lahiry
Termite resistance of Malaysian and exotic woods with plantation potential: Field evaluation
1998 - IRG/WP 98-10289
An in-ground resistance of selected Malaysian and exotic timbers to attack by a representative aggressive subterranean Coptotermes termite was evaluated as part of an on-going collaborative research between the Forest Research Institute of Malaysia and the University of Hawaii on termite control of building timbers under humid tropical conditions. A test site at FRIM, highly susceptible to the sub...
A H H Wong, J K Grace, L H Kirton