Your search resulted in 234 documents. Displaying 25 entries per page.
Influence of the content of organic matter of soil on the degradation of wood by soft rot fungi
1970 - IRG/WP 27
The degradation of wood specimen burried in the soil by soft rot fungi is influenced by a number of factors. These are in particular the water holding capacity, water content, content of organic matter, pH, content of mineral nutritive substances etc. The results of the interlaboratory tests, carried out within the IRG/WP let presume that the intensity of wood degradation occurs proportionally inv...
O Wälchli
Collaborative soft rot tests: Specific gravity loss resulting from soft rot
1973 - IRG/WP 227
It was proposed at the 5th meeting of Working Group II of the IRG in June 1973 in Lahti, Finland, that the specific gravity (swollen volume basis) of test blocks used in the IRG Collaborative Soft Rot Tests should be determined on all the blocks at the completion of the exposure period. Specific gravity determined on the basis of the oven dry weight and water swollen volume was selected because (1...
C R Levy
Analysis of the boron content of preservative treated oak and pitch pine heartwood before and after leaching
1992 - IRG/WP 92-3697
Studies to determine the effects, if any, of a variety of boron formulations on heartwood of English oak and American Pitch pine have been previously reported (King et al (1991)). Small wood blocks were treated, at 10°C or 45°C, with borax, polybor or Boracol 20 for periods of 1 month or 4 months then analysed or continuously leached with tap water for a period of 1 month. Reported results showe...
S McCutcheon, G M Smith, J W Palfreyman, B King
Decay rates and strength and stiffness loss in foundation beams
1992 - IRG/WP 92-1563
The TNO Centre for Timber Research has executed an extensive research programme into the rate of decay in foundation beams, as a result of lowering of ground water tables. The aim of the research was to develop a method, predicting the decrease in strength and stiffness in beams, due to wood decay during drytime of foundation beams. With the calculated extremes in decay, the damage caused by local...
P Esser, H S Buitenkamp
Effects of the sulfuric acid modification of CCA treating solution
1987 - IRG/WP 3415
Sulfuric acid modification of CCA treating solution is often used to control the formation of sludges and undesirable deposits on the surface of treated wood. The consequences of sulfuric acid addition are examined in this work and negative effects are shown to far outweigh any benefits. Major risks include the loss of copper due to leaching from treated wood and the accelerated corrosion of treat...
R F Fox, H J Fry, E A Pasek, A S Ross
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
Assessment of untreated Papua New Guinean timbers against subterranean termites. Progress Report 1
1990 - IRG/WP 1436
Eight major commercial timber species (Intsia palembanica, Pometia pinnata, Homalium foetidum, Dracontomelon dao, Calophyllum spp., Eucalyptus deglupta, Nothofagus spp., and Alstonia scholaris) were exposed in ground contact against termites. Five replicates of heartwood stakes of 25x25x250 mm³ of each species were randomly embedded in the soil. Results after 24 months exposure showed that Kwila ...
M Rokova, H C Konabe
Effects of heart wood extractives in Dahoma (Piptadeniastrum africanum) on decay resistance to white- and brown-rot fungi
2004 - IRG/WP 04-10536
Dahoma (Piptadeniastrum africanum) is a durable but a lesser utilised tropical hardwood species from Ghana that has the potential of being used as an alternative to Iroko (Milicia excelsa) for many end uses. However, the timber gives off a strong odour especially when wet and during processing. The high durability and the strong odour of the timber could be due to the presence of extractives in th...
Zeen Huang, K Maher, S A Amartey
Implications for comparability of laboratory experiments revealed in studies on the effects of population density on the vigour in groups of Coptotermes lacteus (Froggatt) and Nasutitermes exitiosus(Hill) (Isoptera: Rhinotermitidae, Termitidae)
1983 - IRG/WP 1197
(Summary of paper 1194)
The vigour - survival and wood consumption - of groups of Coptotermes lacteus and Nasutitermes exitiosus was measured when termites were kept at different population densities (g termites/ mL) by changing group size and/or volume of the holding container. A characteristic pattern emerged. At low population densities (< 0,01 g/mL) performance of termites improved with an increase in group size; at higher population densities it tended to decline. The impact of altering group size and container volume on termite vigour was most pronounced at low densities; at higher population densities, performance tended to be more stable but declined markedly when termites became overcrowded. In most jar-type experiments on termites, especially those conducted in Europe and the U.S.A., small groups of termites are housed in disproportionately large jars, resulting in very low, sub-optimal population densities. Suggestions are made for improvements in experimental design that would lead to an enhancement of the comparability of results from different laboratories.
M Lenz, R A Barrett, E R Williams
Social and economocal impact of an extension of service life resulting of an adequate preventive treatment. Application to wooden components used in urban areas with a high density of population
1993 - IRG/WP 93-50001-15
Le document évalue les problèmes rencontrés en zone urbaine pour le sauvetage des constructions: coordination de la lutte, délimination des chantieres et des périmètres d'investigation, nuisances causées par les interventions, risques pour la santé, risques pour l'environnement. Coûts. Comparaison socio-économique du traitement préventif et des interventions à posteri...
A T De Lelis, G A C Lopez
Measuring Soil Respiration as a New Approach to Describe the Interaction Between Wood (Treated and Untreated) and Microbiologically Active Soil
2006 - IRG/WP 06-20344
Soil respirometry was employed to examine the relationship between both the performance of copper organic preservatives in contact with and the amount of carbon dioxide evolved from soil and the effect of wood treated with preservatives on carbon turnover in soil. Wood was treated with a range of copper organic preservatives intended for use in ground contact as well as an organic preservative in...
I Stephan, W Mierke
The effect of woody and non woody plants extractives on microbial resistance of non-durable species
2006 - IRG/WP 06-30392
The effect of Elm (Zelkova carpinifolia), Oak (Quercus castanifolia), Mulberry (Morus alba), Ash (Fraxinus excelsior) as woody plants, Rose (Rosa damascene) and Fumitory (Fumaria sp) as non woody plants extractives on durability of Beech (Fagus orientalis), Maple (Acer insgin), Alder (Alnus subcordata), and Lime (Tilia sp) were studied. First wood species having extractives were cut to small piece...
S M Kazemi, A Hosinzadeh, M B Rezaii
Effect of fumigation with Sulfuryl Difluoride on wood inhabiting fungi, a laboratory test
2006 - IRG/WP 06-30410
Special methods are necessary for the control of wood destroying organisms in the preservation of monuments and historic buildings because of the conservation of their originality and uniqueness.
The control of wood destroying organisms can be realized with conventional liquid wood preservatives or alternative methods. One of these methods is the fumigation. One fumigant, which was in the past of...
A Pfeffer, W Unger, G Fröba, G Binker
Protection of a low-density mangrove timber species gewa (Excoecaria agallocha) through preparation of particleboard – An Assessment
2006 - IRG/WP 06-40348
It is now well established that the conversion of low-density and low-cost timbers into laminated, composite and densified form is an alternative of wood protection by means of wood preservatives. Once only the timber species gewa (Excoecaria agallocha) was used for manufacturing newsprint paper in Bangladesh, which is not continued today. The feasibility of commercial production of particleboard ...
A A Mahfuz, M O Hannan, M A Islam, M N Islam , M M Islam, A K Lahiry
Comparative studies on penetration and retention of CCA (C) and creosote in wood from APHID-killed and sound Kenyan-grown Mexican cypress (Cupressus lusitanica)
2006 - IRG/WP 06-40352
Properties of wood from Kenyan-grown Mexican cypress (Cupressus lusitanica), attacked and killed by the cypress aphid (Cinara cupressi), in terms of density and treatability, were investigated in comparison to the properties of wood from sound trees. Density in small wood samples from aphid-killed trees was found lower than density in samples from sound trees, and reduced with tree age in samples...
R Venkatasamy, F M Opar
The influence of wood density on the durabilities of three Ghanaian hardwoods (Nauclea diderrichii (de Wild.) Merr., Nesogordonia papaverifera (A. Chev.) R. Capuron and Corynanthe pachyceras Welw.) )
2007 - IRG/WP 07-10603
Review of factors that influence wood durability shows that although density varies depending on stem position, its role on decay resistance appears controversial. The role density plays in influencing the durability of three hardwoods from Ghana, namely Nauclea diderrichii (de Wild.) Merr., Nesogordonia papaverifera (A. Chev.) R. Capuron) and Corynanthe pachyceras Welw. is therefore investigated ...
C Antwi-Boasiako, A J Pitman, J R Barnett
Treatment of Selected Lesser Used Timber Species against Subterranean Termites using Heartwood Extracts from Teak (Tectona grandis) and Dahoma (Piptadeniastrum africanum)
2007 - IRG/WP 07-30434
Lesser used timber species represent a valuable material for all-purpose uses but the problem is that most of them are not durable. They have, for this reason, been treated with all manner of chemicals to enhance their natural durability, especially in the tropics. Often, most of these chemicals pose a threat to the environment. Currently, one probable measure of avoiding such a threat to the envi...
A Asamoah, C Antwi-Boasiako
White Rot in Eucalyptus Wood: Anatomical Changes and Density Variation by X-Ray Densitometry
2007 - IRG/WP 07-10631
Wood samples of the hybrid Eucalyptus grandis x urophylla attacked by white rot fungi were characterized. Microscopically, the colonization of the fungi was observed in the vessels and radial parenchyma, however the cell walls of the some fibers were attacked, indicating susceptibility to this fungi. Zone lines were observed as a result of interaction and compartmentalization of the fungi. Microsc...
M Tomazello Fo, S Brazolin, M P Chagas
Effect of fiber type and content on the natural durability of wood flour/high density polyethylene composites against rainbow fungus (Coriolus versicolor)
2007 - IRG/WP 07-40387
In order to evaluate the effect of fiber type and content on the natural durability of wood flour/high density polyethylene (HDPE) composites against Coriolus versicolor, samples containing 25% and 50% by weight of various natural fibers and HDPE were selected. Natural fibers included in the study were wood flour, rice hulls, hemp fibers and newsprint. Samples containing 25% and 50% natural fiber ...
A Karimi, M Tajvidi, S Pourabbasi
Effect of Compatibilizer on the Natural Durability of Wood Flour/High Density Polyethylene Composites Against Rainbow Fungus (Coriolus versicolor)
2007 - IRG/WP 07-40388
To evaluate the effect of compatibilizer on the natural durability of wood flour/high density polyethylene composites against Coriolus versicolor, composites containing 25% and 50% by weight maple wood flour and 1% and 2% compatibilizer (Maleic anhydride polyethylene (MAPE)), respectively, were sampled. Identical specimens of the same composites without the compatibilizer were also prepared. ...
Sara Pourabbasi, A Karimi, D Parsapajouh, M Tajvidi, M Soleymani
Decay Resistance Properties of Hemicellulose-Extracted Oriented Strand Board
2008 - IRG/WP 08-10644
There is increasing interest in using cellulosic biomass as the basis for a renewable source of energy. Although the traditional focus has been on cellulose, researchers are also exploring the possibility of using hemicelluloses because they can be removed with hot water leaving the wood product intact for other applications. However, there is concern that removing hemicelluloses from the precur...
C Howell, J Paredes, S Shaler, J Jellison
Quantitative and qualitative losses in wood of oriental spruce, Picea orientalis (L.) Link., induced by insects from forest to utility
2008 - IRG/WP 08-10647
In this study, some quantitative and qualitative losses in wood of oriental spruce, Picea orientalis (L.) Link., induced by insects from forest to utility were evaluated. In experimental plots, volume of trees damaged by Dendroctonus micans (Kug.) was 34% of the volume of total standing spruce trees in the oriental spruce forests of Turkey. The volume of standing trees that D. micans damaged was ...
H A Akinci, M Eroglu, G E Özcan, Ü C Yildiz
Inducing and Stimulating Spalting in Sugar Maple
2008 - IRG/WP 08-10652
Spalted wood has gained popularity in recent years as consumer preference has shifted towards unique and custom products. The process by which spalting is induced in clear lumber has evolved over time, and now involves much more than beer drinking and outdoor burial. Our work on the process of reliably producing spalted wood began in 2004 and involved testing a wide variety of white rot fungi on...
S C Robinson, D L Richter, P E Laks
Natural durability of fast growth plantation Eucalyptus grandis Hill, ex Maiden
2008 - IRG/WP 08-10660
One of the fast growing species cultivated in Uruguay of mayor economical importance is Eucalyptus grandis. Physical and mechanical properties of juvenile and mature wood from different regions have been deeply studied. However, since no scientific data of natural durability of this specie has been reported, natural durability of E. grandis from two sites (Rivera and Rio Negro) was evaluated. Two ...
S Böthig, A Sánchez, J Doldán
Natural durability of different wood species in above ground applications - Weight and MOE loss
2008 - IRG/WP 08-10667
In Norway, exterior wood structures have traditionally, nearly exclusively been made of untreated Norway spruce (Picea abies (L.) Karst) and pressure treated Scots pine (Pinus sylvestris L.). In recent years there has been a tendency that other wood species, like various Norwegian hardwoods or imported species, have been used in exterior above ground applications, often not surface treated. For se...
F G Evans, P-O Flæte, G Alfredsen