Your search resulted in 3148 documents. Displaying 25 entries per page.
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
Editorial corrections to Document No: IRG/WP/304
1972 - IRG/WP 305
Anonymous
Combined effects of the treatment of wood with formaldehyde
1978 - IRG/WP 3117
Treatment of fibrous materials with reagents in a vapor phase is neither new nor unique. Numerous examples exist in literature of vapor phase experiments on cellulose fibers and fabrics, and on wood. For many years the textile research and industry have used vapor phase processes for the treatment of textiles. The chemical modification of cellulose is based on different types of reactions e.g. est...
M Stevens, J Schalck
Surface Barriers for Protection of Culture and Heritage Wooden Objects from Insect Attack
2004 - IRG/WP 04-40286
Anoxic treatment is an environment friendly procedure for eradication of wood boring insects in wooden objects of cultural and historical heritage. However, after the anoxic treatment, wooden antiques remain susceptible to further insect attacks. Possible protection against insects could be provided by the so-called post-repression protective barriers. Potential coating materials for such barriers...
M Petric, M Pavlic, B Kricej, M Humar, F Pohleven
The potential of 2-deoxy-D-glucose as an active ingredient in wood preservation
1999 - IRG/WP 99-30205
2-deoxy-D-glucose (2-DOG) is a potential active ingredient against wood decaying fungi. When dissolved in water, it can be used in pressure treatment of wood. Thereby the wood is protected from attack by wood decaying fungi. A concentration of 1.5% (mean retention 9.7 kg/cubic meter sap-wood) is adequate for brown rot fungi, and 3% (mean retention 19.5 kg/cubic meter sapwood) will also provide protection against white rot fungi. 2-DOG is easily soluble in water, and is therefore easily leached from the wood upon completion of the preservation process. Different types of fixa-tion methods have been tried and evaluated. It is possible to produce 2-DOG by the hydrolysis of chitin, a constituent of the exterior skeleton of shellfish and insects. There is a potential for exploita-tion of this waste product provided by the crab and shrimp industry. The yield of 1 kg of fresh shrimp is 75 g of 2-DOG.
O V Frederiksen, A P Koch
Kinetic modelling of adsorption of quaternary ammonium compounds by Scots pine wood sawdust (Pinus sylvestris L.)
2005 - IRG/WP 05-30369
The adsorption of new quaternary ammonium compounds from aqueous solutions onto Scots pine wood (Pinus sylvestris L.) sawdust was studied. The pseudo first- and second- order kinetic models were used for the mathematical description of the sorption dynamic process of QACs onto wood. The highest correlation coefficients were obtained for the pseudo-second order kinetic model, those suggest that che...
J Zabielska-Matejuk
Airborne algae as a wood degradation factor
1992 - IRG/WP 92-1549
The occurrence of airborne (aerophytic) algae on wood is a very frequent phenomenon. However, there is currently a lack of information concerning their effect on the wood tissue. Some important genus of algae infesting wood under natural conditions are listed, as well as the results of experimental studies in the "in vitro" culture concerning the effect of two selected algal species on some physic...
K J Krajewski, J Wazny
International Directory of Members and Sponsors 2001
2001 - IRG/WP 01-60136
IRG Secretariat
New developments in wood preservation
1974 - IRG/WP 335
Most of the developments in wood preservation in recent years have been stimulated by changing circumstances, particularly the increasing interest in reducing hazards and environmental, pollution but also the serious difficulties that are now being encountered in obtaining economic supplies of established preservatives. There is perhaps a danger that new controls to reduce pollution dangers may be...
B A Richardson
Specific gravity and moisture content of particleboards treated with various chemicals
2005 - IRG/WP 05-40310
The aim of the study was to investigated the effects of particleboard treated with various chemical substances on specific gravity and moisture content
The wood raw material used in the experiments were the mixture of coniferous wood [70%, Pinus brutia Ten., Pinus nigra Arn (Lamb.), Cedrus libani Ait.] and black poplar (30%, Populus nigra L.). In this mixture, barks have been accepted up to 5 per...
Ü C Yildiz, A A Var, H Kalaycioglu, S Yildiz
Water-based water repellents for treatment of wood
1987 - IRG/WP 3446
The water uptake by wood can be reduced by treatment with a water repellent. The water repellents most commonly used are solvent based. In the present work a new type of water repellent that is water-based has been investigated. Two different treatments have shown an effect of the same order as a commercial solvent based product. The cellular distribution of the water repellents has been investiga...
I G Svensson, G Hägglund, I Johansson, W B Banks
Differences in feeding activity among colonies of Formosan subterranean termite Coptotermes formosanus Shiraki
1983 - IRG/WP 1202
Feeding activities of 7 colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were examined. Wood-consumption rates among colonies differed significantly, ranging from 23.80-78.48 mg/g/day. This large intraspecific variation raised a question of whether differences in feeding activity reported for other termite species were due to interspecific differences. When rates were...
N-Y Su, J P La Fage
Wood preservatives ecotoxicology on Gammarus pulex (L.) - toward an environmental monitoring method and a getting rid of pollution process
2005 - IRG/WP 05-50224-9
Wood preservatives can have a strong impact on freshwater invertebrates when used close to aquatic ecosystems. It has been reported in Jura that different arthropod taxa, specially crustaceans, have disappeared along several kilometers downstream from factories using insecticides and fungicides as wood preservatives.
The crustacean Gammarus pulex (L.) is a relevant bioindicator to characterize th...
O Adam, F Degiorgi, G Crini, P-M Badot
Wood preservation in East European countries
1989 - IRG/WP 3527
The paper discusses the main problems of wood preservation in Bulgaria, Czechoslovakia, German DR, Hungary, Poland, Rumania and the USSR. The main types of wood preservatives produced have been presented, as well as the state of standarization to test their properties. There have been considered methods of wood treatment in use and application range of treated wood....
J Wazny
The isolation of actinomycetes from wood in ground contact and the sea
1980 - IRG/WP 1110
M S Cavalcante, R A Eaton
Detection of incipient brown rot decay in wood by fourier transform infrared spectrometry
1987 - IRG/WP 2275
Fourier transform infrared spectrometry was evaluated as a possible method for detecting different levels of brown-rot decay in pine sapwood. By using first derivative spectra and regression analysis, an equation based on 4 absorption peaks, normalized with an internal standard peak, was developed. The correlation between weight loss and absorption was highly significant indicating that this is a ...
D D Nicholas, T Schultz
The rate of redistribution and loss of leachable preservatives under service conditions
1993 - IRG/WP 93-30026
This paper describes experiments carried out to determine patterns of preservative redistribution and any associated losses which occur when wood containing unfixed water-soluble wood preservatives is exposed to service conditions where leaching is possible. Scots pine sapwood treated with disodium octaborate was used as a model system. Results are recorded and discussed for trials representing pa...
R J Orsler, G E Holland
The performance of wood preservatives in soil-bed soft rot tests
1993 - IRG/WP 93-20007
Testing the efficacy of wood preservatives in soil is recognised as a fundamental part of the assessment of long-term wood protection in ground contact. Laboratory based tests can provide a hazardous environment in which a preservative can be challenged by a range of micro-organisms. This paper presents the results of tests carried out to investigate the performance of wood preservatives in a wet ...
G R Williams, S Caswell
Report on marine borer attack on some timbers treated with CCA wood preservative and exposed for three months in sea-water
1985 - IRG/WP 4112
Destruction of timbers by marine borers has long been a problem for the coastal population of Thailand. The use of heavy durable timbers with frequent maintenance, or total replacement, is the only solution for fishermen with their fishing craft or marine installations, meanwhile wharves or other large scale constructions are usually made by using concrete pilings or concrete casings. In recogniti...
A Rananand, W Yoosukh, U Sittiphuprasert
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
A comparison of the effectiveness of a vacuum oven and a wind tunnel in the accelerated ageing of treated wood by evaporation
1989 - IRG/WP 2334
R J Orsler, G E Holland
Above ground testing of wood preservatives - some experiences from Sweden
1995 - IRG/WP 95-20079
Field stake tests for the evaluation of wood preservatives have been used for more than 50 years in Sweden. In the Nordic countries a system for approval of wood preservatives, which includes field test, has also been in operation for more than 25 years. This system has been described in an IRG Document by Henningson & Jermer (1988). The Nordic system is now in a process of harmonization with ...
B Henningsson, Ö Bergman
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
Effects of the anaerobic wood decay bacterium Clostridium xylanolyticum on unbleached Pinus and Eucalyptus pulp
1991 - IRG/WP 1506
Clostridium xylanolyticum has been shown to produce extracellular enzymes capable of degrading wood. The present work was conducted to quantify growth on various lignocellulosic substrates and degradation of pulped wood fibre. In the latter tests Clostridium xylanolyticum was incubated at 35°C under anaerobic conditions in a medium containing 0.2% (w/v) peptone and 4% (w/v) unbleached Pinus and E...
G D Shelver, U Matai, W Van Wyk, A A W Baecker
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