Your search resulted in 324 documents. Displaying 25 entries per page.
About the relations between the natural durability of some tropical species and their extractives content
1983 - IRG/WP 1208
G R Y Déon
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
Eastern redcedar included sapwood: Resistance to mold and termites under laboratory conditions
2012 - IRG/WP 12-10765
The heartwood of eastern redcedar (Juniperus virginiana) frequently contains areas of light-colored wood. This “included sapwood” is considered to be a defect by some manufacturers. In this study, sapwood, included sapwood and heartwood samples from five eastern redcedar trees were exposed to mold fungi or to subterranean termites in a no-choice feeding test. Extractives content was also measu...
C Köse, A M Taylor
Natural durability, ethanol-toluene extractives and phenol content prediction of eight wood species from Madagascar using NIRS multispecific models
2018 - IRG/WP 18-10926
Madagascar has nearly 4000 species of trees and shrubs, but wood properties of only 200 species have been studied. Some properties, such as the natural durability or chemical composition are of importance for adequate and optimal use of these timber species. Since durability tests take long time and chemical analyzes can be very expensive, alternative methods such as near infrared spectroscopy (NI...
A R Razafimahatratra, H Rakotovololonalimanana, M-F Thévenon, C Belloncle, G Chaix, T Ramananantoandro
The effect of certain wood extractives on the growth of marine micro-organisms
1977 - IRG/WP 438
S E J Furtado, E B G Jones, J D Bultman
Moisture content levels and decay of hemlock
1986 - IRG/WP 1287
As a model of decay conditions of wooden members in wooden houses, a decay test was set up in which samples of western hemlock (Tsuga heterophylla) under 4 moisture levels were examined. Each week the samples were weighed and if the weights indicated that their moisture contents were lower than the expected levels, distilled water was added. Every 8 weeks 3 samples from each condition were oven dr...
New technique to analyze impregnation processes
1988 - IRG/WP 2304
Equipment has been developed to measure liquid flow in wood during impregnation processes. Basic principles of flow measurements using directly heated negative temperature coefficient thermistors, and some characteristics of the hardware developed are presented in this paper....
J P Hösli
A medium for mass culturing of a bamboo boring beetle Dinoderus minutus Fabricius
1983 - IRG/WP 1182
The bamboo is a traditional product of Japan. But its susceptibility to insects is one of the most important problems. The author has found that for the determination of the effectiveness of insecticides it is very easy to obtain sufficiently numerous adults of Dinoderus minutus by using Buckwheat Cake. The Buckwheat Cake is prepared with buckwheat flour and thin paper. The author has previously f...
Influence of moisture content of rubber wood on the growth of Botryodiplodia theobromae
1993 - IRG/WP 93-10029
Botryodiplodia theobromae is the main fungus causing sapstain on rubber wood (Hevea brasiliensis). The entry and establishment of the stain fungus is nighly influenced by the moisture content of the wood. To determine the optimum moisture content of wood required for maximum growth of Botryodiplodia theobromae wood blocks at different moisture contents were inoculated with the test fungus and incu...
E J M Florence, R Gnanaharan, J K Sharma
Soil virulence tests using Scots pine sapwood
1973 - IRG/WP 222
Following the tests reported in Document No: IRG/WP/210, in which soils from different laboratories were investigated for virulence, supplementary tests have been carried out using Scots pine sapwood and an extended incubation period....
J K Carey, J G Savory
Chemical compounds from Eperua falcata and Eperua grandiflora heartwood and their biological activities against wood destroying fungus (Coriolus versicolor)
2005 - IRG/WP 05-30373
The chemistry analysis of the compounds present in dichloromethane and ethanolic fraction as well as bioassays enables to understand the durability differences of Eperua falcata and Eperua grandiflora. The principal distinction between these two species is the acidic subfraction of diterpenoic extract, which is antifungic in Eperua falcata when tested in in-vitro conditions. This study also enable...
N Amusant, C Moretti, B Richard, E Prost, J M Nuzillard, M-F Thévenon
Co-operative research project on L-joint testing. Sampling after 8 months exposure
1983 - IRG/WP 2208
It was anticipated in Document No IRG/WP/2192 that exposure of L-joints by the European co-operators would take place on 1 April 1983. Where L-joints were exposed at this time, sampling after 8 months exposure is due on 1 December 1983. The present document draws attention to relevant previous documents which describe the sampling methods to be adopted. It also provides Tables for recording the re...
J K Carey, A F Bravery
Comparison of the agar-block and soil-block methods used for evaluation of fungitoxic value of QAC and CCA wood preservatives
1994 - IRG/WP 94-20039
The modyfied agar-block and soil-block methods were used for comparing the fungitoxic value of QAC and CCA type preservatives against Coniophora puteana and Coniophora olivacea The mass loss and moisture contents of wood were analysed....
J Wazny, L J Cookson
Rates of emission from CCA-treated wood in the marine environment: measurement, modelling and requirements for further research
2001 - IRG/WP 01-50166-12
Accurate estimates of rates of emission of leachate from preservative treated wood are crucial for realistic predictions of the environmental impact of its use in maritime construction. Estimates are available for some commonly used preservatives, but these vary widely. Though variable, these measurements suggest that emission generally decreases exponentially with time. Part of the variation is d...
S M Cragg, C J Brown, R A Albuquerque, R A Eaton
Methodology challenges in developing a transfer of natural durability from sawmill residues, illustrated by experiences with white cypress (Callitris glaucophylla)
2000 - IRG/WP 00-20203
The transfer of durability-conferring extractives from durable to non-durable wood has been accomplished often, but usually as an educational exercise rather than as a commercially oriented process. In the latter environment, many factors previously overlooked become vitally important. How to study them, in the absence of well-developed methodology and given the shorter timeframes being demanded b...
M J Kennedy, M A Powell
Collaborative soft rot tests: Programme and test method
1973 - IRG/WP 229
J G Savory, J K Carey
Observations on the failure of anti-sapstain treated timber under non-drying conditions
1990 - IRG/WP 1437
A range of bacteria and yeasts were isolated from antisapstain treated timber and fresh sawdust. Solution samples containing 100 ppm of TCMTB in a nutrient medium were inoculated with these organisms and incubated at 25°C for 5 days. The levels of TCMTB remaining in solution were determined by HPLC analysis after this time. Results indicated high losses of active ingredient for a range of organis...
G R Williams
Collaborative soft rot tests: Interim report on PRL tests of Cu/Cr/As preservative using method of Document No: IRG/WP/208
1972 - IRG/WP 211
Preservative: Tanalith CT.106 - Results obtained with beech are given in the table and indicate a toxic limit of 16.7-19.2 kg/m³ - The initial soil moisture content was adjusted to 27.8% (the water holding capacity). Noticeable drying out has occurred in some of the test bottles....
J G Savory
Soft rot and bacterial decay in preservative treated eucalypt power transmission poles
1982 - IRG/WP 1155
Bacterial type decay was observed in CCA and PCP treated eucalypt power transmission poles. Detailed observations made with the SEM revealed bacterial colonisation and decay, especially in fibres. Plug samples taken from poles throughout Queensland were examined for preservative retention and presence of soft-rot decay. The severity of decay was different according to location, retention and speci...
L E Leightley
Microbial biofouling of 10-40% naphthalene in creosote treated and untreated wooden pilings in the marine environment
1978 - IRG/WP 442
R R Colwell, P L Fish, D A Webb, A J Emery
A standardised procedure for the treatment of timber with test chemicals
1986 - IRG/WP 2257
A procedure is described which allows the standardisation of sample handling and data manipulation during trials invastigating the treatability of timber with test chemicals. The use of computer software allows the data to be handled efficiently....
J Norton, A Zosars, L E Leightley
Nitrogen content of soils at field sites
1981 - IRG/WP 1133
Nine participants in the Collaborative Field Experiment submitted samples for nitrogen analysis to this laboratory as requested by Leightley (IRG/WP/3162). These arrived in a variety of conditions e.g. wet, dried, sterilised and unsterilised and sometimes spent a considerable time in transit. Soils varied in cellular fraction organic matter content, some were obviously sieved prior to postage whil...
B King, G Mowe
Co-operative research project on L-joint testing. Progress report to March 1988
1988 - IRG/WP 2315
Further sets of data received from CTFT (France), BAM (Germany) and PRL (UK) after 46-48 months exposure and STU (Sweden) after 22 months exposure are presented and discussed in conjunction with data reported previously. Colonisation and attack of the L-joints has progressed with increasing exposure period. The new data are generally in agreement with those presented previously and the major diffe...
J K Carey, A F Bravery
The resistance of fifteen Indonesian tropical wood species to the powder post beetle Heterobostrychus aequalis
1990 - IRG/WP 1429
A preliminary laboratory test on the resistance of 15 tropical wood species to Heterobostrychus aequalis has been carried out using small samples of 7.5 x 5 x 1.5 cm³. The results reveal that Pinus merkusii and Agathis borneensis are very susceptible to Heterobostrychus aequalis. Other 13 species vary between susceptible to resistance There is no signifisant relation between starch content and th...
Jasni, Nana Supriana
Time dependent over-uptake of etherificated melamine resins
1998 - IRG/WP 98-40109
Waterbased methanol-etherificated melamine-formaldehyde resins can increase the fungal resistance of the treated wood though they are known to be non-toxic. Therefore melamine-resins are at the present an object of research activities of European projects and of some companies. The paper highlights the importance of quoting the duration of the diffusion when immersed in the treating solution, as m...
D Lukowsky, R-D Peek