Your search resulted in 3405 documents. Displaying 25 entries per page.
Chemically modified tannin and tannin-copper complexes as preservatives for wood
2001 - IRG/WP 01-30271
The efficacy of Mimosa tannin, chemically modified tannin, and tannin-copper complexes as wood preservatives was studied. When the tannin-ammonia-CuCl2 solutions were impregnated into wood specimens in a one-step procedure, a large quantity of the tannin-copper complex was fixed in the specimens. Little of the complex was leached from specimens by a weathering treatment, and these specimens showed...
H Yamaguchi
Observations on the destruction of fishing craft in India by marine wood-borers with special reference to the West Coast
1981 - IRG/WP 472
The paper highlights the economic importance of the destruction of fishing craft in India by marine wood-destroying agencies. The annual loss involved is to the extent of over 94 million rupees. Thirty-nine spectes and one variety of woodborer have so far been recorded from India, of which Bankia campanellata, Bankia carinata, Bankia rochi, Dicyathifer manni, Lyrodus pedicellatus, Teredo clappi, T...
L N Santhakumaran, J C Jain
Preliminary investigation on the natural durability of Guayule (Parthenium argentatum)-based wood products
2000 - IRG/WP 00-40154
Conventional preservatives used to protect wood from insect and microbial damages are presently of major concern to human health and the environment. Finding alternative and economical preservatives has not been successful. Previous studies have shown that the resinous material extracted from the guayule plant (Parthenium argentatum, Gray) has both insect- and microbial-resistant properties. Unfor...
F S Nakayama, P Chow, D S Bajwa, J A Youngquist, J H Muehl, A M Krzysik
The potential use of impregnated coconut wood for power line poles in rural areas of Java
1980 - IRG/WP 3130
Electrification of rural areas in Java needs thousands of power line poles which are relatively cheap in price, but have adequate strength and are fairly durable. A choice of wood species is available in the country. One alternative is coconut wood found in abundance in the villages. This may give a solution to Java's needs since supplies are readily available almost everywhere. Based on ...
H Yudodibroto
List of fungi in soft-rot tests
1975 - IRG/WP 105
This list gives information on the terrestrial and marine species and strains of fungi tested for soft-rot ability in pure culture with data on their decay activity in untreated wood. An index of the timber species tested is added. The compilation is based on 1) the list of soft-rot fungi of the former OECD Group (Doc.No. 27/DAS/CSI/M/559), Oct. 1968, prepared by R. Rösch and W. Liese, 2) informa...
G Seehann, W Liese, B Kess
Wood protecting chemicals for the 21st century
1993 - IRG/WP 93-30018
After assessing the past research with protection chemicals, this paper proposes future avenues for research and development in wood protection. Three scenarios are put forward for consideration. First, more is not better and future systems will emphasize combination formulations which enhance properties while providing biological efficacy. Second, current systems, especially those based on copper...
H M Barnes
Effect of leaching temperature and water acidity on the loss of metal elements from CCA treated timber in aquatic applications. Part 1: Laboratory scale investigation
1995 - IRG/WP 95-50046
In order to investigate the applicability of current prestandard leaching test methods, a series of experiments has been performed on CCA impregnated wood dealing with the influence of pH, temperature and agitation of the surrounding water. The leaching method used in this first part of the investigation is the European prestandard drafted by CEN/TC38/WG11, a short term dynamic leaching test under...
G M F Van Eetvelde, R J Orsler, G E Holland, M Stevens
Algal growth resistance of paints for coating of wood; a laboratory study
1997 - IRG/WP 97-10213
Twelve paints were tested for resistance against algae. In addition, one algicidal compound commercially used for remedial treatments of algal growth on paints was tested for its effectiveness for prevention of algal growth. An agar diffusion bioassay was employed in which paint films on filter paper discs were placed on mineral salt medium and sprayed with an algal suspension containing a mixture...
J Bjurman
PCP in aquatic environments arising from historic contamination at wood processing and preservation sites
1995 - IRG/WP 95-50040-14
Three different studies are reported that assess the impacts of Pentachlorophenol (PCP) in aquatic environments arising from its historic use at sawmilling and wood preservation sites. These studies involved New Zealand wood processing facilities, and collectively they aimed to measure the transport of PCP from sawmill sites into the aquatic environment, determine the background environmental conc...
J S Gifford, P N McFarlane, M C Judd, S M Anderson
A model for attack at a distance from the hyphae based on studies with the brown rot Coniophora puteana
1995 - IRG/WP 95-10104
In timber infested by brown rot fungi, a rapid loss in strength is attributed to production of hydroxyl radicals (HO·) at a distance from the hyphae. The immediate precursor is Fenton's reagent (Fe(II)/H2O2), but the pathways leading to Fe(II) and H2O2 have remained unclear. Cellobiose dehydrogenase, purified from cultures of Coniophora puteana, will couple oxidation of cellodextrins to ...
S M Hyde, P M Wood
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
The future for chromium in wood preservation
1985 - IRG/WP 3332
Most water-borne preservatives contain CrVI compounds, originally to reduce corrosion although now also to improve toxicant fixation. Chromium contributes to preservation and this is recognised in, for example, New Zealand and USA where chromium contents are included in calculations of overall preservative activity of CCA formulations, but chromium may also have anti-stain and joinery (millwork) p...
B A Richardson, T R G Cox
The effect of oil-borne preservative treatments on the shear strength of FRP/wood composite adhesive bonds
2003 - IRG/WP 03-40265
Reinforcement of structural wood components with Fiber Reinforced Polymer (FRP) will enhance the beam’s strength, but actual data on long-term durability is sparse, not well documented or not readily accessible. In this study, bond properties of FRP-wood composite materials were investigated following treatment with creosote or copper naphthenate preservatives. The properties investigated inclu...
B Herzog, B Goodell, R Lopez-Anido
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
Leaching of components from CCF treated timber in ground contact
1998 - IRG/WP 98-50108
In order to investigate the depletion of different CCF-salts during service small stakes (10*10*450mm³) were treated with five water-borne wood preservatives and after fixation brought into ground contact for several years. After failing some of the broken down stakes were used to determine the remaining concentration of relevant ions and their distribution in different segments of the stakes.
A...
E Melcher
Water transfer in wood in relation to fungal attack in building - Effect of condensation and diffusion
1992 - IRG/WP 92-1543
Wood is continuously exchanging moisture with the surrounding atmosphere, the temperature and relative humidity are important factors. Wood moisture in this case is not enough to provoque decay by fungi. However, when, during the night, condensation appears cyclically, wood absorbs water and moisture content may be sufficiently high to allow development if drying does not take place. The water tra...
D Dirol, J-M Vergnaud
Exclusion of anions from the wood cell wall
1991 - IRG/WP 3661
Anionic components of wood preservatives and fire retardants such, as arsenates and phosphates, equilibrate at much lower concentrations in the cell wall bound water than in the free solution in the cell lumens. A degree of anion exclusion is expected in wood, due to the Donnan membrane effect. Fixed anions in the wood cell wall, produced by pH-dependent dissociation of the weak acid groups in woo...
P A Cooper
A non-destructive testing technique for wood poles
1987 - IRG/WP 2293
A method has been developed to evaluate the stiffness and condition of a wood pole based on structural dynamics. This paper describes the results of tests performed on nearly 200 wood utility poles across Western Canada. A high correlation exists between the dynamic non-destructive test and direct mechanical tests. The need for an accurate non-destructive testing technique is demonstrated by the f...
W M Murphy, D E Franklin, R A Palylyk
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 4: Conversion reactions during storage
1974 - IRG/WP 332
Precipitates simulating those produced in wood by preservative fixation reactions were prepared by the reduction of Boliden K 33 and Celcure AP solutions with hydrogen peroxide and hydrazine. The pH changes on aging at 20 and 50°C were studied and related to the chemistry of fixation previously described. Hydrolysis of copper arsenates may render arsenic acid temporarily water soluble pending pre...
S-E Dahlgren
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
Wood preservation in Nigeria - Its increasing relevance, observed constraints and potential as a forest conservation option
1992 - IRG/WP 92-3732
The paper discusses the demand and supply of wood and wood products in Nigeria and points out that in view of the large population (88 million) and search for wood for housing and furniture, the demand exceeds supply. There is great shortage of industrial and domestic woods resulting in underutilization of installed machineries in forest industries and low profit margin. Under this prevailing cond...
M A Odeyinde, S C Ifebueme
Effects of hard water, sea water and humic acid on the release of CCA components from treated wood
2005 - IRG/WP 05-50228
Leaching medium is an important factor affecting release of preservative components from treated wood because physical and chemical characteristics of medium increase or decrease the solubility of fixed preservative components. This study evaluated the leaching properties of copper, chromium and arsenic elements from chromated copper arsenate (CCA)-treated wood specimens subjected to laboratory le...
S N Kartal, W J Hwang, Y Imamura
The resistance of wood coated with different water-borne paints against colonisation by decay fungi
1996 - IRG/WP 96-10165
The susceptibility of wood painted with model paints of known composition to decay fungi was tested without previous weathering. Included in the study were five alkyd emulsion paints and five acrylic paints; one linseed oil paint and two solvent-borne alkyd paints. It was found that several components influenced the susceptibility of these paints. The results of the present study indicate that the...
J Bjurman
Resistance of pine and spruce heartwood against decay - The effect of wood chemical composition and coating with water-borne wood oil product
2006 - IRG/WP 06-10597
Natural durability of wood has been widely studied, but the combination of the natural durability and different treatments has not been the focus of many studies. The durability of wooden products is mainly based on the water permeability and the resistance against organisms. In this study, the water absorption and decay resistance of sapwood and heartwood of Scots pine and Norway spruce were exam...
H Viitanen, S Metsä-Kortelainen, T Laakso
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