Your search resulted in 475 documents. Displaying 25 entries per page.
Experiences with supervision schemes for treated timber in Denmark
1984 - IRG/WP 3315
Since 1967 a voluntary supervision scheme for vacuum-pressure treatment was established in Denmark. In 1976 the Nordic Wood Preservation Council - NWPC - established a scheme based on wood preservation classes for treated timber as a joint technical standard valid in Denmark, Finland, Norway and Sweden. This paper deals with inspection results over 17 years for CCA treatment within our organizatio...
J Sabroe
Prevention of non-microbial sapwood discolorations in hardwood lumber: chemical and mechanical treatments
1997 - IRG/WP 97-30137
Sapwood discolorations in hardwood lumber that are non-microbial in origin result from the formation of pigmented starch-like granules in ray parenchyma cells. These discolorations can be prevented by treating unseasoned lumber with an antioxidant (sodium bisulfite). Exposing unseasoned lumber to microwaves or treating logs with fumigants also will prevent these discolorations. Subjecting unseason...
T L Amburgey, S Kitchens
Subterranean termite foraging behaviour and the development of baiting methods used for termite control by the Division of Forest Products
1994 - IRG/WP 94-10058
Given the premise that alternatives to current subterranean termite control measures using organochlorine insecticides and arsenic trioxide have been actively researched by our Division for over ten years, emphasis on baiting methods in controlling these termites has been a major facet of our research. Recently, the new Australian Standard (AS 3660 -1993) was released which outlined the use of phy...
J R J French, J W Creffield, B M Ahmed
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
The kinetics of anhydride modification reactions of wood. Experimental results and theoretical modelling
1998 - IRG/WP 98-40125
Although the chemical modification of wood remains a fertile area for research, there has been little work performed on the kinetics of the modification process. The reaction kinetics of a series of linear chain and cyclic anhydrides has been studied and activation energies of the reaction determined. The reaction kinetic profiles are determined by the relative rates of reaction of the reagent wit...
C A S Hill, J G Hillier
FLUROX, a new breakthrough in insect control for wood preservation
1995 - IRG/WP 95-30079
FLUROX (flufenoxuron) is an acylurea insecticide which acts as a growth regulator in insects. FLUROX inhibits the production of chitin - the exoskeleton or 'skin' of the insect. When the exposed larva attempt to moult to its next stage of development, it is unable to produce a new skin and dies. FLUROX has been found to be extremely active against wood borers, when applied in a p...
A R Valcke, M Pallaske
Effects of chemical pretreatment of Douglas-fir heartwood on efficacy of potential bioprotection agents
1990 - IRG/WP 1440
Biological protection against wood decay fungi represents an environmentally attractive alternative to the use of chemicals; however, the process of identifying suitable candidates and the conditions that ensure successful protection pose major challenges. One critical aspect of this problem is to identify organisms that can rapidly and uniformly colonize the wood. Wood contains low levels of nutr...
B Dawson-Andoh, J J Morrell
Effects of soil physical and chemical characteristics on adsorption of leached CCA and ACQ preservative components
2003 - IRG/WP 03-50200
The objective of this study was to examine the effect of soil characteristics on adsorption of wood preservative components from CCA and ACQ preservative systems. Adsorption of leached CCA and ACQ preservative components in soils with different characteristics were studied. Three soils (clay, sandy and organic) were investigated using different concentrations of leach water of CCA and ACQ wood pr...
S Stefanovic, P A Cooper
Biological and chemical investigations for the assessment of the environmental impact of wood preservative components
1999 - IRG/WP 99-50127
This study was carried out in order to investigate the suitability of biological and chemical techniques to evaluate the environmental impact of wood preservatives depleted from impregnated wood. Small specimens (15*25*50 mm3) of Scots pine sapwood (Pinus sylvestris) were treated with a CCB salt. After fixation the treated and untreated samples were washed-out according EN 84, and the different le...
E Melcher, H-W Wegen
Fungal decay resistance of Rubber wood treated with heartwood extract of Rosewood
2005 - IRG/WP 05-30367
Alcoholic extract of Dalbergia latifolia heartwood was studied for its toxicity towards wood decaying fungi. Rubber wood blocks were treated with this extract to three different retention levels (0.1%, 0.2% & 0.5%) and the treated wood blocks were assessed for their resistance towards two white rot and two brown rot fungi. Treated blocks showed improved resistance over the control blocks. At 0...
A K Sethy, H C Nagaveni, S Mohan, K T Chandrashekar
Microwave modification of Yellow Stringybark (Eucalyptus Muelleriana) posts for impregnation with Copper-Chrom-Arsenic (CCA) preservatives
2000 - IRG/WP 00-40185
Yellow Stringybark posts with diameters ranging from 60-100 mm were microwave conditioned using a 60 kW microwave (MW) generator. A substantial improvement in heartwood penetration of preservatives and relaxation of growth stresses was indicated such that there was no split formation following drying of the posts. High preservative absorption of copper-chrome-arsenic (CCA) was achieved ranging fro...
G Torgovnikov, P Vinden
A review of the efficacy and uses of deltamethrin for wood preservation
1996 - IRG/WP 96-30105
The synthetic pyrethroid deltamethrin, is one of the most active insecticides available for protecting and curing wood from attack by beetles and termites. Freshly felled trees can be protected against bark beetles by spraying to run off with a 0.025% Al solution (K-Otek EC25) with negligible leaching. Alternatively, sawn timber may be dipped in a 0.0125% Al solution for short to medium term prote...
A J Adams, J L Lindars
Modification of solid wood: research and practical potential
1997 - IRG/WP 97-40098
The polymeric structure of the wooden cellwall mainly consists cellulose, hemicellulose and lignin. The most reactive sites on these components are the hydroxyl groups. The cellwall polymers (and its reactive hydroxyl groups) are responsible for most physical and chemical properties of wood. By changing the basic chemistry of the cellwall polymers, it is possible to change different undesirable at...
H Militz, E P J Beckers, W J Homan
Chemical treatment of chips for outdoor storage. Evaluation of sodium N-methyldithiocarbamate + sodium 2,4-dinitrophenol treatment
1980 - IRG/WP 2134
Fresh slash pine chips were treated by spraying them with a dilute aqueous solution of sodium N-methyldithiocarbamate and sodium 2,4-dinitrophenol. The were then formed into an experimental chip file 10 feet high, and the pile was maintained for seven months. The treatment effectively slowed heat release and retarded losses in wood substances, tall oil, pulp yield, and pulp strenght. Under certain...
E L Springer, M Benjamin, W C Feist, L L Zoch, G J Hajny
Biological degradation resistance of wood acetylated with thioacetic acid
1983 - IRG/WP 3223
Chemically, modification of wood is being considered as an alternative to conventional preservation by toxic chemicals. Acetylated wood has been reported to be quite resistant to most biodegrading organisms at weight percent gains (WPG) around 15-19. The conventional acetylation techniques with acethic anhyrdride result in generation of acetic acid. However, acetylation with thioacetic acid overco...
S Kumar, S C Agarwal
Three years of field tests with "Lignomer" stakes in ground contact
1981 - IRG/WP 3166
The "Lignomer" (Wood Polymer Composite) is a material obtained during the polymerisation of various monomers or its mixtures in wood. As laboratory tests have shown, this material is characterized by a high resistance against biological deteriorating agents. The laboratory investigations on the durability of various materials against biological deterioration are in many instances extended by field...
K Lutomski
Tropical In-Ground Durability of Structural Sarawak Hardwoods Impregnated to High Retention with CCA-salts, CCA-oxide and FCAP after 20 Years Exposure
2005 - IRG/WP 05-30384
Statistical analysis (ANOVA) was conducted on durability (termite and decay combined) rating data collected over 20 years exposure period of over 140 species of Sarawak timbers with altogether 30,000 stake specimens, at the Forest Department’s Sibu “graveyard” stake test sites from 1977. About 20 replicated stakes were pressure-treated to refusal with 10% g/ml concentration of up to 3 CCA-sa...
Wang Choon Ling, A H H Wong
Laser incising of spruce lumber for improved preservative penetration
1991 - IRG/WP 3646
Red spruce heartwood specimens were incised using a range of laser beam power levels and pulse durations. The penetration of CCA through these holes into the wood was monitored after pressure treatment. In addition, green and dried spruce samples were incised using two patterns with incision densities of either 16.1 holes/in² or 21.3 holes/in². Following CCA pressure treatment the samples were t...
B Goodell, F A Kamke, Jing Liu
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
Decomposition of biocides in aqueous media cases of MTC and TCMTB
1993 - IRG/WP 93-50001-26
Our laboratory is interested in the fate of modern biocide molecules in the environment. Here we present recent work which has been done on the fate of two compounds with fungicidal and bactericidal properties: methylenedithiocyanate (MTC: NCS - CH2 - SCN) and thiocyanomethylthiobenzothiazol (TCMTB). We have studied separately the influence of pH, temperature and ultraviolet irradiation in aqueous...
R Perraud, M Papazian
"Refractory" is a relative term. Incised alpine fir is treatable
1991 - IRG/WP 3670
While certain wood species carry a reputation for being 'treatable' this normally refers to the sapwood. For most Canadian species, heartwood penetration is the major determinant of whether treatment meets Canadian, USA and Japanese standards and in this respect alpine fir turns out to be a treatable species. Alpine fir is the fir component of the Western Canadian spruce-pine-fir...
P I Morris
Method to determine the depth of penetration of the biologically active components of wood preservatives
1978 - IRG/WP 2108
A time-saving method for determining the depth of penetration of the biologically active components of wood preservatives is described. The test specimens were obtained by cutting thin slices from the wood either parallel or perpendicular to the treated surface. The slices were then exposed to fungal attack. A good correlation was found between the test results obtained by the modified German Stan...
H-P Sutter
Evaluation of the permeability of fast grown wood species
1995 - IRG/WP 95-40042
The low natural durability of certain species of wood, implies the need for applying a protecting treatment to increase its life in service. Because of this, a knowledge of the permeability properties of the wood is desired. In this work, a simple and reliable method to evaluate the wood permeability is presented. For that, we have been used fast grown species, with low natural durability, Poplar ...
M T De Troya, A M Navarrete, E Sanchez, J E Garcia de los Rios, E L Rodríguez Trobajo
Treatment of wood by diffusion of salts
1976 - IRG/WP 368
A brief survey is given on the treatment of wood by diffusion of salts. The compounds used for this process, mainly boron and fluorine compounds, are mentioned and the factors influencing diffusion described. The main pre-condition is a high moisture content of the wood of above 40%. Fields of application are fresh roundwood, remedial treatment of poles and sleepers, preservation of posts and espe...
G Becker
Chemical and biological investigations of double-vacuum treated windows after 7½ years in service
1985 - IRG/WP 3339
Earlier investigations of double-vacuum treated windows after five years in service have shown that tributyltin oxide (TBTO) degrades to di- and monobutyltin compounds and that the resistance of the wood against decay decreases. An investigation 2.5 years later of the same windows shows that the degradation of TBTO proceeds fast. After 7.5 years in service only 15-35% of the remaining organotin co...
M-L Edlund, J Jermer, B Henningsson, W Hintze