Your search resulted in 856 documents. Displaying 25 entries per page.
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
Preservative treatment specifications in Fiji
1982 - IRG/WP 3190
The preservative treatment specification used in Fiji is outlined. Reference is made to a basic end use classification and to locally approved treatment processes, preservatives and retention levels. Amenability ratings are defined and penetration requirements for broad commodities indicated. Currently commercial operations rely entirely on pressure treatment with copper-chrome-arsenic multisalts ...
A S Alston
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
A new type of biocide suitable for use in different fields of wood preservation
1993 - IRG/WP 93-30014
A new type of polymeric biocides was developed containing quaternary ammonium and boron ester groups as active structure elements, to overcome the disadvantages of AAC's in wood preservation use and to utilise their good performance due to a broad efficacy against fungi on the other hand. The new biocides called polymeric betains have been tested in laboratory and field tests and especial...
V Barth, H Härtner
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
Tool wear for vapor boron-treated composites
2001 - IRG/WP 01-40209
A series of composites, including oriented strandboard and medium density fiberboard, were treated via vapor boron technology. Treated samples were compared to untreated composites using a tool force measuring technique. Tool forces measured with a dynamometer indicated a positive effect of boron addition. Visual and SEM examination indicated a wider wear zone on the rake face of the tool for the ...
W A Jones, H M Barnes, H A Stewart, R J Murphy
Effect of post-treatment processing on leachability of ACZA-treated douglas-fir lumber
1998 - IRG/WP 98-50109
The effect of post-treatment procedures that more rapidly precipitate copper, zinc, and arsenic in douglas-fir treated with ammoniacal copper zinc arsenate (ACZA) on subsequent leaching resistance were investigated at two retentions (6.4 and 40 kg/m3). Total leaching was greater from boards treated to the higher retention. At both levels, copper was lost at the highest rate. Post-treatment process...
J J Morrell, C S Love, S Kumar, C M Freitag
Survey of conditioning treatment practices in the Philippines
1975 - IRG/WP 349
The wood preservation industry in the Philippines is at present beset by many problems. An association of the industry similar to those existing in other countries has only been initiated last year by FORPRIDECOM. It is hoped that the formal organisation of this association will bring into focus the importance of this particular industry in the economic and industrial development of the country. L...
R F Casin
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
Animal blood protein as a component of new, non-toxic wood preservatives fixing organic active compounds in wood
2003 - IRG/WP 03-30312
Application of natural organic compounds and simple physico-chemical treatments in wood conservation has, as its objective, not only its protection against biological agents but, equally importantly, protection of natural environment by gradual abandonment of toxic constituents still applied commonly on a wide scale. The introduction into wood of new, non-toxic impregnation agents manufactured on ...
B Mazela, I Polus
Tilting and vacuum treatment - two methods to obtain a non-dripping freshly treated timber
1989 - IRG/WP 3535
Modern impregnation plants are designed to prevent spread of impregnation solutions from the plant through leakage, etc. It is also important that freshly treated timber does not spread solutions through dripping on the storage area. To prevent this, the impregnation procedure is terminated with a vacuum period. In many plants in Sweden this period is minimized or even excluded to gain time. Inste...
I Johansson, M-L Edlund
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
Dimensational stabilisation of wood
1981 - IRG/WP 3171
A review is given of the studies on the dimensional stabilisation of wood which have been carried out in the laboratory 5.14 "Wood Technology" since 1967. All stabilisation methods known have first been compiled from the available literature. Practical studies were then started. Wood was treated with monomers (styrene, methyl metacrylate, isocyanate), formaldehyde, tannin and sugar. Despite a sati...
A Burmester
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
After 18 years, preservative dipping and brush treating continue to provide protection to shingles of western wood species
1997 - IRG/WP 97-30156
The presence of residual preservation in dip-treated and brush-treated shingles of various species from the western United States was assessed 18 years after installation using Aspergillus bioassays. The performance of western redcedar (Thuja plicata) was compared to western hemlock (Tsuga heterophylla), sugar pine (Pinus lambertiana) and western larch (Larix occidentalis). Untreated shingles of a...
T C Scheffer, D J Miller, J J Morrell
An anti-termite formulation for soil treatment with natural products and its efficacy against Coptotermes formosanus Shiraki
2003 - IRG/WP 03-30319
An anti-termite formulation of an environmental conservation type for soil treatment was developed. The formulation was composed of decanoic acid (n-capric acid, an fatty acid derived from coconut oil with ten carbons) as an active ingredient and other natural products. Experiments to examine the efficacy of the formulation against Coptotermes formosanus Shiraki were conducted at the termite field...
S Yoshida, T Nakagaki, A Igarashi, A Enoki
Specifying preservative-treated resistant timber: Conforming to European Standards
2001 - IRG/WP 01-20235
The most common construction timbers used in the UK are of low natural durability and, generally, resistant to preservative treatment. These include species of spruce, hemlock and fir. However, their characteristically limited and non-uniform uptake of preservatives may still confer sufficient protection to give satisfactory durability performance in terms of biological resistance. This paper desc...
E D Suttie, A F Bravery, T B Dearling
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
Effects of steaming heat treatment of wood on the stimulation of termite feeding
1997 - IRG/WP 97-10212
At the 26th IRG conference, we reported that steamed Japanese larch heartwood samples were suffered a serious attack by subterranean termite, Coptotermes formosanus both in choice and no-choice feeding tests. This is possibly caused by the yield of termites stimulants in the wood samples resulting from the steaming process. Since the steaming heat treatment has often been applied to other several ...
S Doi, Y Kurimoto, M Takahashi, T Yoshimura
Internal pressure development in Douglas fir lumber during pressure treatment
1997 - IRG/WP 97-40091
Preservative treatment of Douglas fir lumber to meet current industry standards poses a major challenge and a variety of methods have been developed to overcome these problems. One aspect for treatment improvement that has received less attention is the relative effect of treatment parameters on changes in pressure within the wood. Previous studies of spruce and radiata pine suggest that internal ...
P F Schneider, J J Morrell
Accidental mold/termite testing of high density fiberboard (HDF) treated with borates and N’N-naphthaloylhydroxylamine (NHA)
2003 - IRG/WP 03-10462
High density fibreboard (HDF) was made from beech and pine furnish (50:50) and treated with boric acid (0.1-3%), borax (0.1-3%) or N'-N-(1,8-naphthalyl) hydroxylamine (NHA) (0.1-1%) prior to gluing with urea formaldehyde (UF) resin in order to determine resistance to Eastern subterranean termites (Reticulitermes flavipes Kollar), the most economically important termite species in North Am...
S N Kartal, H H Burdsall Jr, F Green III
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