Your search resulted in 1274 documents. Displaying 25 entries per page.
Report of field test results for dichloro-n-octyl-isothiazolone: A potential new wood preservative
1988 - IRG/WP 3495
In a previous report (IRG/WP/3306) we presented preliminary laboratory test results on 4,5-dichloro-2-n-octyl-4-isothiazolone (RH 287). Laboratory data indicated toxic threshold values for RH 287 ranging from 0.37 to 0.50 kg/m³. In this report we present field test results on an IRG L-joint test and an in-ground stake test for RH 287, pentachlorophenol and biocide free test units. (a) L-joint tes...
D E Greenley, B M Hegarty
Borates and their biological applications
1998 - IRG/WP 98-30178
This paper reviews some of the many biological applications of borates. Boron is a ubiquitous element found widely distributed in the environment and is a normal component of a healthy diet. Elemental boron does not exist in nature, but is always found combined with oxygen in compounds called borates. Boron is an essential micronutrient for plants, and there is evidence to suggest that boron is of...
J D Lloyd
Antifungal mechanism of dichloro-N-octylisothiazolone
1998 - IRG/WP 98-30183
4,5-dichloro-N-octylisothiazolin-3-one (DCOI) is a member of the isothiazolone class of preservatives, whose antimicrobial mechanism of action has been intensively studied over the last decade. DCOI has also been intensively studied for use in wood preservation. The isothiazolones are electrophilic molecules that rapidly react with thiol groups to form covalently bonded isothiazolone-thiol adducts. This ability to bond with thiol groups is crucial to their ability to act as preservatives.
Thiol groups are present in proteins as part of the amino acid cysteine, where they play an important role in maintaining protein structure and function. A number of enzymes have thiol groups at the site where the enzyme function is performed, and these thiol groups may participate in the enzyme reaction. If the isothiazolone reacts with this thiol group, the activity of the enzyme is inhibited. Our studies have shown that there are several enzymes in the Krebs cycle that are inhibited by isothiazolones and these enzymes are required to generate energy and perform many biosynthetic functions. Reflective of this, DCOI has been shown to be a rapid inhibitor of cellular respiration, causing the cell to cease consuming oxygen almost immediately upon contact with DCOI. The multiplicity of targets and their central importance to the metabolism of the cell, as well as the fact that all microbes use at least parts of the Krebs cycle, can be related to the low use levels and broad spectrum of activity of DCOI.
The antimicrobial mechanism of DCOI results in a potent rapid-acting preservative with a broad spectrum of antifungal and antibacterial activity that is effective at low levels.
J S Chapman, M A Diehl, K B Fearnside, L E Leightley
The use of C CP/MAS NMR in the chemical identification of decayed and undecayed, tropical timber species
1984 - IRG/WP 1224
13C CP/MAS NMR was found to be an extremely powerful tool for elucidating the chemical composition of Eucalyptus maculata, Pinus elliottii and Alstonia scholaris. The differences in lignin composition were different for each timber and discussed in relation to decay caused by soft-rot and white rot fungi. In particular the presence of syringyl and guaiacyl lignin types are discussed.
L E Leightley
The interaction of polyflavonoid tannins with CCA in Pinus radiata
1987 - IRG/WP 3422
Polyflavonoid tannins complex easily and rapidly with metal ions such as copper, chromium, and arsenic. such complexes in high-tannin-containing CCA treated hardwoods might result in essentially under-treated timber. Four aspects of this interaction were investigated: 1) The relationship between tannin contents of seven hardwoods (Betula pendula, Alstonia scholaris, Fagus sylvatica, Liquidambar st...
K G Ryan, D V Plackett
Steam conditioning of partially dried radiata and Corsican pine roundwood
1988 - IRG/WP 3499
The effect of partial air drying prior to steam conditioning and its effect on subsequent preservative treatment by the Bethell treatment process was investigated. A high standard of preservative treatment was obtained in both radiata and Corsican pine, irrespective of whether a period of partial drying was imposed before or after steam conditioning....
P Vinden, D R Page, K Nasheri
Depletion of wood preservatives after four years' marine exposure in Mt. Maunganui harbour, NZ
1994 - IRG/WP 94-50036
This paper reports on chemical analysis of marine test samples exposed in Mt. Maunganui harbour, New Zealand from 1977 to 1981. Depletion data for a Class II CCA, a CCA-A formulation, acid copper chromate and ammoniacal copper arsenate are presented. The results suggest differences in the rate of loss of individual preservative components among the four formulations and redistribution of individua...
K J Archer, A F Preston, C M Chittenden, D R Page
An approach to testing the preventive effectiveness of preservative treatments for wooden joinery
1981 - IRG/WP 2156
The ecological sequence established in field trial samples exposed out of ground contact has shown the need for outdoor exposure in testing potential joinery preservative pretreatments. A system of exposure of L-joint units is proposed. Data obtained by examining samples destructively show promise as the basis for predicting service life after relatively short exposure periods (within 2 years)....
J K Carey, A F Bravery, J G Savory
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water: Final report
1987 - IRG/WP 4133
Three timbers chosen as reference species were treated with 3, 6 and 10% solutions of CCA and CCB preservatives and exposed for up to 93 months at 8 tropical and temperate marine sites. Eleven local species treated in the same way were exposed at 4 of the 8 sites. There was no apparent difference in performance between CCA and CCB treated specimens. The severest test site was Panama Canal but mari...
R A Eaton
Copper naphthenate-treated Southern Pine pole stubs in field exposure. -Part 2: Chemical characterization of full size pole stubs 12 years after treatment
2000 - IRG/WP 00-30246
This study examines the influence of pre-treatment and post-treatment steaming on the character and physio-chemical nature of copper naphthenate in hydrocarbon solvent treated pine in larger, pole diameter, pole stub-length samples. This work is the continuation of two projects that began almost a decade ago. Previous reports indicated that certain morphological changes might occur in small labora...
H M Barnes, D P Kamdem, M H Freeman
Water-repellent additive for CCA
1991 - IRG/WP 3655
Hickson have developed a water repellent additive for incorporation into copper-chromium-arsenate timber treatment solutions. The water repellent emulsion shows good stability in the treatment solution, is easily incorporated and applied in a single stage treatment. No modifications to the additive is safe to treatment schedule are usually needed and use. Weathering of the treated wood is substant...
P Warburton, R F Fox, J A Cornfield
Collaborative soft rot test: Amended test method
1972 - IRG/WP 208
The initial draft of a standard test method (Document IRG/WP/201) was discussed at the meeting in Brussels in 1971. It was agreed that a revised draft should be prepared and that the Princes Risborough Laboratory (formerly FPRL) should conduct a trial test using the method as a preliminary to the main collaborative test....
J G Savory
Diffusion of bifluorides and borates from preservative rods in laminated beams
1991 - IRG/WP 3644
Laminated beams from spruce, pine and larch were treated with two preservative rods, based on bifluorides and octaborate respectively. After 3 and 6 months placed in different climates (65% r.h., 100% r.h., water) the diffusion of the active ingredient was measured. After the 6 months period, the diffusion of the bifluorides was, in all species, ca. 5 times larger than the diffusion from octaborat...
H Militz
Technique for monitoring absorption during a vacuum pressure process
1992 - IRG/WP 92-3696
A laboratory technique was developed and an apparatus constructed which allowed for the direct and continuous measurement and observation of volumetric uptake of water-borne preservative into wood samples throughout a controlled vacuum-pressure treatment process. Fractional filling of void space was calculated. Graphing (fractional saturation) against time allows prediction of optimum cycle length...
A J Pendlebury, J A Petty
Evaluation of the leach resistance and preservative efficacy of novel biocides as surface treatments applied by brush to spruce (Picea abies)
1998 - IRG/WP 98-30170
The comparative leach resistance and preservative efficacy of a number of alternative organic preservatives (available from Zeneca Specialties) and selected commercially available biocides as surface coatings to wood in Hazard Class 3 have been assessed. Two concentrations of test preservatives were applied by brush to Spruce (Picea abies), including formulation and untreated controls. A leaching ...
I M Tierney, A Bruce, D C R Sinclair, T Yeates
Wood preservation and the environment: A Canadian perspective
1990 - IRG/WP 3577
The non-pressure (surface) and pressure treatment of wood impacts on the environment in four ways. These are: through the production of treated wood at sawmills and pressure treating facilities; during the storage of treated wood prior to use; when the pressure treated wood is placed in service; and finally, when the treated product reaches the end of its useful life and must be disposed. By refer...
J N R Ruddick
X-ray analysis of selected anatomical structures in copper/chrome/arsenic treated wood
1973 - IRG/WP 320
Application of analytical electron microscopy to problems in wood preservation has been very limited. Indeed, less than ten workers appear to have published their results using the technique, and of these' only two papers deal with energy dispersion procedures in the scanning electron microscope; the others employ the more familiar wavelength dispersive methods of the electron probe....
H Greaves
A laboratory soil-block decay evaluation of plywoods edge-treated with preservatives
1982 - IRG/WP 2174
Preservative-treated plywood used under conditions or severe decay hazard frequently has its original, or cut edges, protected by the application of a field-cut preservative. This study uses a laboratory test method to compare the efficacy of four commercial preservative treatments against two commonly occurring brown-rot fungi. The results are not meant to indicate the service life of such treate...
R S Smith, A Byrne
Lignin-copper, a new wood preservative without arsenic and chromium
1992 - IRG/WP 92-3702
A more environmentally sound treatment for wood with preservatives containing no arsenic or chromium, has been developed and studied on a laboratory scale. The method involves a first step impregnation with an aqueous solution containing modified, water-soluble kraft lignin followed by a second step involving impregnation with a copper salt solution to give fixation of the lignin into a water-inso...
B Ohlsson, R Simonson
Protection of Ochroma pyramidale from fungal decay with N,N-napthaloylhyroxylamine
1998 - IRG/WP 98-30182
Fungal decay of wood in service results in billions of dollars (U.S.) in losses annually. Recent environmental restrictions, both U.S. and international, are limiting and eliminating the use of broad-spectrum, heavy metal biocides for wood preservation. Restrictions result primarily from problems with disposal. New wood preservatives need to be developed and tested which specifically target key el...
F Green III, T L Highley
The performance of softwood species used as poles in Queensland
1985 - IRG/WP 1253
In Queensland, the conifer Pinus elliottii could provide material suitable for use as poles. Full size pole material has been readily treated with CCA with no significant loss in strength. Seasoning of logs prior to treatment requires particular attention in the wet tropical and sub-tropical regions of Queensland. Experimental and in service field tests have indicated excellent performance of CCA ...
L E Leightley
A wood preservative for the future: Copper dimethyldithiocarbamate
1994 - IRG/WP 94-30045
The development of a new wood preservative, copper dimethyl-dithiocarbamate (CDDC) is reviewed in this paper. CDDC is formed in situ by dual pressure treatments. Laboratory and field efficacy trials, physical and chemical properties of the preservative solutions and treated wood, and plant handling characteristics of the system are examined....
D K Stokes, M H Freeman, T L Woods, R D Arsenault
Soil-bed studies (Part 3): A cause of failure of multisalt preservatives following soil-bed exposure
1983 - IRG/WP 3261
P Vinden, J F Levy, D J Dickinson
Thirty-four year test of on-site preservative treatments to control decay in wood above ground
1993 - IRG/WP 93-30015
This research was initiated in 1958 to investigate efficacy of various preservatives and treating methods for new lumber going into exterior structures of buildings. Post-rail units (2x4 inches) constructed of Southern Pine sapwood, Douglas-fir heartwood, and mill run western hemlock were dip- or brush-treated before or after assembly. Units were trested with pentachlorophenol in various petroleum...
T L Highley, T C Scheffer
Termite field test results of preservative treated and modified woods in Kumamoto, Japan
2001 - IRG/WP 01-30275
Various preservative treated or modified wood stakes other than CCA, were buried in the soil, maximum for six years in Kumamoto, south west side of Japan. In this area, two main termite species, Coptotermes formosanus and Reticulitermes speratus, are distributed. After two years in field, untreated sapwood of sugi (Cryptomeria japonica) were observed severe attacks by termites, but the preservativ...
K Suzuki