Your search resulted in 560 documents. Displaying 25 entries per page.
Evaluation of extractives from African Padauk (Pterocarpus soyauxii Taub.) for protection of non decay resistant species
2002 - IRG/WP 02-10419
The development of a wood preservative made up of natural extracts is a potentially attractive prospect for the wood preservation industry. In this study, organic solvents were used to remove extractives from African padauk wood samples. The solvent was removed by rotoevaporation, and the total content of the viscous extracts determined to be 54.4mg/ml.
The toxicity of various extracts concentrat...
P Nzokou, D P Kamdem
Natural durability of tamarack (Larix laricina (Du Roi) K. Koch)
1998 - IRG/WP 98-10277
Eastern larch or tamarack (Larix laricina (Du Roi) K. Koch) lumber from New Brunswick, Canada was evaluated for heartwood natural durability according to ASTM D2017-81. The natural durability of tamarack heartwood exposed to two brown rot fungi, Gloeophyllum trabeum and Postia placenta was low and generally inferior to that of the heartwood of spruce (Picea sp.) and white pine (Pinus strobus L.) a...
U Srinivasan, A Taylor, P A Cooper
A questionnaire survey to establish the perceptions of UK specifiers concerning the key material attributes of timer for use in marine and fresh water engineering
2004 - IRG/WP 04-10519
Engineers have a key role in making informed decisions on the type of materials to be used in the schemes they design and construct. Currently, in England and Wales, it is believed that some £500m per year is invested in flood and coastal defence engineering. There is a lack of centralised data in the UK holding information on timber for usage in fluvial and, particularly coastal engineering. A...
J R Williams, G S Sawyer, S M Cragg, J Simm
Changes in transverse wood permeability during the drying of rimu and radiata pine
1990 - IRG/WP 3636
When softwoods are dried and subsequently impregnated with waterborne preservatives two problems frequently occur, preservative screening of multi-salt preservatives and difficult re-drying. To study the causes, the permeability of rimu and radiata pine wood has been measured along the three principal directions. The radial and tangential permeabilities of the green sapwood of the two species were...
R E Booker
Partial seasoning and preservative treatment systems for pine roundwood
1982 - IRG/WP 3187
Experimental trials at FRI, Rotorua showed that the steaming schedule normally used for steaming and venting is also suitable for steaming and vacuum seasoning. Applying vacuum of up to -84 kPa immediately after steaming did not increase the initial loss of wood moisture significantly in comparison to steam/venting. The main improvement to wood condition by using steam/vacuum appeared to be to dis...
A J Bergervoet
Survey of practical methods for conditioning of forest products before preservative treatment
1971 - IRG/WP 39
The seasoning of forest products is undertaken for a wide range of end uses and is becoming increasingly required for applications and building construction and secondary manufacturing industries. A wide range of applications of new technology and specifically required seasoning schedules is being actively developed for such requirements, but less attention has been given to the means by which woo...
J Rak, T S McKnight
Development of a novel treatment process and its applications
1998 - IRG/WP 98-40111
An efficient treatment process called "Isostatic Compression Recovery (ICR) Process" for impregnating liquids into wood has been developed. The process comprises steps of isostatic compression of wood in the liquid at temperatures above its softening temperature and subsequent recovery of its original volume under liquid pressure. A large amount of surrounding liquid is absorbed into the wood in t...
T Arakawa, M Funato, A Hoshino, T Muraki
On the changes of natural durability of wood sterilised by gamma radiation
2006 - IRG/WP 06-10571
The preliminary study data of natural durability of wood in lab conditions against rot fungi dependency on different sterilisation method have been presented. In the research, white rot fungus Schizophyllum commune Fr.: Fr. and brown rot fungus Poria placenta (Fries) Coke sensu J. Erikson. on the Scots pine were tested. Cobalt 60Co was used as a gamma radiation source at the dosage of 30 kGy. Cont...
R Despot, M Hasan, M Glavaš, G Rep
Comparative studies of natural durability of Japanese cedar (Cryptomeria japonica D. Don) among the geographic cultivates
2006 - IRG/WP 06-10592
Variation of natural durability of Japanese cedar (Cryptomeria japonica D. Don) (also known as Sugi) was investigated by accelerated tests for decay (Fomitopsis palustris (Berk. et Curt.) Murr.) and termite (Reticulitermes speratus Kolbe) attacks on 13 clones of Sugi trees from Kyushu-Okinawa Region (Fukuka, Ooita, Saga, Miyazaki, Kagoshima). For this purpose, 57 twenty-five years old Sugi trees o...
I Usta, K Takata, S Doi
The natural durability of wood in different use classes - PART II
2006 - IRG/WP 06-10598
The natural durability of important European wood species has been tested on 3970 speci¬mens in field trials. The wood was exposed at five test sites in Germany with different climates, at each site in European use class 4 and 3 (with and without soil contact). Within European use class 3 three different expositions were tested: vertical with sheltered end grain, vertical unsheltered and horizont...
A O Rapp, U Augusta, K Brandt
Overview of European discussions on Standardisation and list of proposed standards for WPC performance qualification
2006 - IRG/WP 06-20345
The standardisation is a driving force to promote the development of Wood Polymer Composites (WPC) by giving confidence to users and consumers. In Europe, the high interest of WPC require at this time a diffusion of information concerning the performances of WPC products. The WPC performances must be assessed according relevant standards in order to qualify the intrinsic properties of WPC (mechani...
G Labat, M Vernois, T Gay
CCB Preservative treatment of split muli (Melocanna baccifera ) bamboo by soaking process
2006 - IRG/WP 06-40336
This study was carried out in order to investigate the retention of chemicals inside the split muli ( Melocanna baccifera ) bamboo after preservative treatment by soaking process. Treatment with 10% aqueous solution of CCB (copper-chrome-boron) was applied in split bamboo of two sizes (1/4 part and 1/8 part) at three different moisture contents and five time periods (24, 48, 72, 96, 120 hours). It...
K Akhter, M H Chowdhury
Further discussion of biological durability assessments of acetylated wood from several European institutes
2006 - IRG/WP 06-40340
In the last decade, interest in the development of wood modification systems has increased in Europe. Alongside several industrial initiatives for heat treatments, there have also been scaling up and pilot plant projects for chemical wood modification. Between 2000-03, the European Commission funded the "Thematic Network on Wood Modification". This paper features a re-evaluation of work undertaken...
D Jones, W Homan, F Bongers
The Influence of Extractives on Western Redcedar’s Equilibrium Moisture Content
2006 - IRG/WP 06-40331
The high natural durability of western redcedar (Thuja plicata Donn) heartwood is often attributed to the presence of the thujaplicins, which are toxic to fungi. However, sound, twenty-five year old western redcedar shakes and shingles were found to contain only traces of the thujaplicins, but significant quantities of plicatic acid (which is only weakly toxic to fungi). This suggests that factors...
R Stirling, P I Morris
On the reasons of Prunus africana natural durability
2007 - IRG/WP 07-10611
Analysis of Prunus africana heartwood extractives was studied with the aim of understanding the reasons for its high natural durability. Soxhlet extractions of wood powder using different solvents were carried out. Effect of each extracts at different concentrations was evaluated on the growth of several fungi among which Coriolus versicolor, Poria placenta, and Aureobasidium pullulans. Results sh...
F Mburu, S Dumarçay, M F Thévenon, P Gérardin
Marine exposure assessment in southern Portugal of the natural resistance of a number of lesser known species of tropical hardwoods to teredinid and limnoriid borers
2007 - IRG/WP 07-10614
Naturally durable species of timber are used as an alternative to preservative treated timber for marine structures, but many species have not been evaluated for their potential for use in this environment. EN 275 specifies a 5-year test period - too long a period for screening tests to be economically viable. In this study, candidate timber species were selected for testing in the sea on the basi...
J R Williams, S M Cragg, L M S Borges, J D Icely, G S Sawyer
The characteristics of biodegradation mechanism of gamma-irradiated wood
2007 - IRG/WP 07-20352
Gamma radiation, as an easy, fast and effective sterilisation method, changes molecular structure in pest’s living cells, but also in wooden cell walls. Radiation-induced depolymerisation causes significant changes in wood properties crucial for laboratory testing of wood-preservative effectiveness. Natural durability of wood against rot fungi in lab conditions dependency on different sterilisat...
R Despot, M Hasan, F Pohleven, M Humar, G Rep
Methods for Determining the Role of Extractives in the Natural Durability of Western Redcedar Heartwood
2007 - IRG/WP 07-20356
The durability of western redcedar heartwood is influenced by a number of different extractives operating by different mechanisms. In order to guide a systematic isolation of extractives with high fungal toxicity, a micro-bioassay has been developed for measuring the fungal toxicity of extractive fractions. Two additional assays quantify the anti-radical and metal chelating properties of cedar ext...
R Stirling, C R Daniels, J E Clark, P I Morris
Study of natural durability of Spanish Eucalyptus globulus wood
2007 - IRG/WP 07-10617
In some countries such as Australia, the wood of Eucalyptus globulus is recommended, due to its high durability, in risk situations where attack by organisms is likely to occur. In Galicia this species has been used for many decades for timber structures, which are still used. However, European Standard EN-350-2 places Eucalyptus globulus in the worst category of natural durability, a situation th...
D Lorenzo, M T Troya, M J Prieto, C Baso, M Touza
Wood furfurylation process development. Part 1: Oscillating Pressure Method
2007 - IRG/WP 07-40376
Furfurylated wood (wood modified by furfuryl alcohol) has over the last years gained marked shares from both tropical wood and conventional preservative treated wood and this has, in turn, generated several research projects concerning process development. The impregnation of spruce is well known from literature to be a difficult task. Furthermore, the sapwood of Scandinavian-grown Scots pine is a...
E Larnøy, M Westin, B Källander, S Lande
Wood furfurylation process development. Part 2: Lowry impregnation trials
2007 - IRG/WP 07-40377
The objective was to evaluate whether Lowry-impregnation of Scots pine with FA100-mix, instead of the FA40-mix, would lead to similar or slightly higher WPGs and to investigate any potential changes in penetration pattern. The results indicate that the penetration was better, also penetrating the outer zone of the heartwood. Furthermore, it was possible to reduce the WPG-levels for pine down to 50...
M Westin, E Larnøy, S Lande
Preservative treatment of Golla cane (Daemonorops jenkinsiana) by pressure process
2007 - IRG/WP 07-40379
The feasibility of preservative treatment of golla cane (Daemonorops jenkinsiana (Griff) Mart). by pressure process has been studied using water borne preservatives CCB (copper-chrome-boron). Cane samples of three different lengths 1m, 2m and 3 m. were treated at different pressure and time period to evaluate the extent of penetration and retention of preservative chemicals. It was observed that t...
K Akhter, M Hoque Chowdhury
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
The influence of different creosote process parameters on penetration, retention and bleeding on glulam
2007 - IRG/WP 07-40368
Different process parameters were used to treat Scots Pine glulam beams with creosote. Parameters like pre-heating, pre-pressure time, pressure and pressure time were changed. Most treatments gave a full or almost full penetration of creosote into the sapwood, but the uptake of creosote in the sapwood varies.
All samples, except the one with poor penetration, showed heavily bleeding of creosote ...
F G Evans
Evaluating the Process of ACQ-Treated Woods with TGAand CEM Analysis
2007 - IRG/WP 07-20374
To provide an understanding of the fundamental thermal behaviour and the disposal-end products of ACQ-treated woods, this study is comprised of two categories of examination. The first is related to the use of TGA under different thermal decomposition conditions (nitrogen or air, and 5 or 40 oC/min), and the use of EDX to examine certain residual elements of the char. The second applies the CEM ...
Han Chien Lin, Tsang-Chyi Shiah, Jung Ting Tsai