Your search resulted in 1225 documents. Displaying 25 entries per page.
Preliminary study of the fungicidal and structural variability in copper naphthenates and naphthenic acids
1996 - IRG/WP 96-30114
Copper naphthenates, an oil-borne wood preservative listed by the American Wood-Preservers' Association (AWPA), is manufactured by complexing copper(II) with naphthenic acids. Prior to AWPA listing as a wood preservative, field experiments showed that copper naphthenates generally had good stability and were active against wood-destroying organisms. Recently, however, there have been reports ...
T Schultz, D D Nicholas, L L Ingram Jr, T H Fisher
A new concept of oxalic acid biosynthesis in physiology of copper-tolerant brown-rot fungi
2001 - IRG/WP 01-10394
Recently, a wide variety of roles of oxalic acid (oxalate) in wood decay systems have been receiving much attention. Copper tolerance of wood-rotting basidiomycetes has been believed to be due to the detoxification of copper wood preservatives by oxalate produced by these fungi. However, biochemical mechanism of oxalate biosynthesis in relation to physiology of wood-rotting fungi has not been eluc...
E Munir, T Hattori, M Shimada
Comparative performance of several ammoniacal copper preservative systems
1997 - IRG/WP 97-30151
The efficacy of several ammoniacal copper-based wood preservative systems was evaluated in this study. The selection of potential co-biocides was based on the results of an agar plate test. Following this, the most promising systems were evaluated in a standard field stake test. Good correlation was found between the agar plate and field stake test results. Of the preservative systems tested, copp...
D D Nicholas, T Schultz
Efficacy of copper:propiconazole and copper:citrate systems in ground contact exposure at a site with copper tolerant fungi
2003 - IRG/WP 03-30305
Southern yellow pine (SYP) sapwood field stakes were treated with copper alone (ammoniacal copper carbonate, ACC) at four levels, or three levels of copper (1.6, 3.2, or 6.4 kgm-3, as CuO), air-dried, then re-treated with propiconazole in a light organic solvent at 0.07, 0.3, or 0.7 kgm-3 retentions. In a separate study, SYP field stakes were treated with three levels of ACC to give 6.7, 13.4 or ...
D D Nicholas, T Schultz
A possible role of unique TCA cycles in wood-rotting basidiomycetes
2003 - IRG/WP 03-10461
The copper tolerant brown-rot fungus, Fomitopsis palustris, acquires metabolic energy by use of the constitutively-occurring Kornberg’s glyoxylate cycle coordinating with oxalate biosynthesis and glucose oxidation (Erman Munir et al. Proc. Natl. Acad. Sci. USA, (2001) 98, 11126-11130). Furthermore, this fungus does not have the normal TCA cycle, lacking 2-oxoglutarate dehydrogenase which is a ke...
E Munir, T Hattori, M Shimada
A Comprehensive Review of Copper as a Biocide, with a Focus on Micronized Copper
2008 - IRG/WP 08-30486
This paper reviews the wood preservative biocide active ingredient copper and delvers into new and previously unpublished data regarding the new micronized formulations which are now in vogue and widespread use in N. America in all residential treated lumber markets. Included in this review is the overall discussion of copper containing formulations used for pressure treated wood used over the las...
M H Freeman, C R McIntyre
The Form of Copper: Does It Really Matter?
2009 - IRG/WP 09-30513
In recent years, several micronized copper formulations for lumber treatment have supplanted the solubilized copper formulations that in turn replaced CCA after its voluntary relabeling in 2004. The micronized or dispersed copper systems use finely ground but solid copper particles and deposit those particles within the wood framework. In contrast, copper in the soluble formulations is relativel...
C R McIntyre, M H Freeman, T F Shupe, Q Wu, D P Kamdem
Sensitivity to Copper of Basidiospores from Copper Tolerant Fungi: Fomitopsis palustris and Oligoporus placentus
2010 - IRG/WP 10-10707
Copper continues to be an important fungicide in wood preservation. It is the primary component of the preservatives that have replaced chromated copper arsenate for treated wood in residential construction in North America. However, a co-biocide is normally needed to protect against copper tolerant organisms. Previous work has shown that the spores of at least one copper tolerant fungus, Oligopo...
C S Woo, P I Morris
Effectiveness of Copper Indicators in Treated Wood Exposed to Copper Tolerant Fungi
2014 - IRG/WP 14-20554
Wood treated with a copper based wood preservative will typically turn a green color. While the depth of copper penetration can be readily discerned from the green color of the copper it is standard practice in research and commercial treating plants to make use of a color reagent such as Chrome Azurol S, Rubeanic acid or PAN indicator to reveal the penetration more clearly. When copper treat...
L Jin, K Brown, A Zahora, K Archer
Untreated and copper-treated wood soaked in sodium oxalate: Effects of decay by copper-tolerant and copper-sensitive fungi
2017 - IRG/WP 17-10888
Copper is widely used as the primary component in wood protectants because it demonstrates a broad range of biocidal properties. However, a key concern with using copper in wood preservative formulations is the possibility for brown-rot basidiomycetes to resist the toxic effect. Many brown-rot basidiomycetes have evolved mechanisms, like the production and accumulation of oxalate, which helps thes...
K M Ohno, G T Kirker, A B Bishell, C A Clausen
Extracellular layers of wood decay fungi and copper tolerance
1983 - IRG/WP 1180
Extracellular layers around the hyphae of brown, white and soft rot fungi have been examined using electron microscopy. These layers were isolated for identification. Particular interest was directed towards the extracellular layers of copper-tolerant soft rot fungi....
D M Francis, L E Leightley
Evaluation of wood treated with copper-based preservatives for Cu loss during exposure to heat and copper-tolerant Bacillus licheniformis
1999 - IRG/WP 99-20155
Copper-based wood preservatives need to be effective against exposure to all types of microorganisms. Wood treated with six copper-based preservatives was exposed to 121°C and 20 psi pressure for 15 minutes under standard autoclave conditions and the copper-tolerant bacterium, Bacillus licheniformis CC01, for 10 d at 28°C and 150 rpm. Sixteen to 37 percent of the copper was released from the woo...
D M Crawford, C A Clausen
Proposed degradation pathway for quaternary ammonium compounds by mould fungi
1996 - IRG/WP 96-10166
One group of chemicals that has attracted considerable attention as potential wood preservatives are the quaternary ammonium compounds (QACs). Based upon results of previous research this study confirmed the degradation pathway employed in QAC-tolerant fungi. For this experiment the two dialkylammonium compounds didecyldimethylammonnium chloride and dioctyldimethylammonium chloride were used. QAC-...
J L Bürgel, J Dubois, J N R Ruddick
The use of chlorothalonil for protection against mold and sapstain fungi. Part 1: Laboratory evaluation
1989 - IRG/WP 3515
Laboratory screening of chlorothalonil alone and in combination with other fungicides was conducted against six mold and sapstain fungi. The most promising treatments appear to be chlorothalonil supplemented with CCA or copper-8-quinolinolate. Field tests have been implemented....
J A Micales, T L Highley, A L Richter
Fungal degradation of wood treated with metal-based preservatives. Part 2: Redox states of chromium
1996 - IRG/WP 96-10164
Concerns have arisen about the leaching of heavy metals from wood treated with metal-based preservatives, such as chromated copper arsenate (CCA). Of particular concern is the toxic redox state of chromium and arsenic in aging and decayed CCA-treated wood. Generally, hexavalent chromium is more toxic than trivalent chromium and trivalent arsenic is more toxic than pentavalent arsenic. The desired ...
B Illman, S Bajt, T L Highley
Oxalic acid production of fifteen brown-rot fungi in copper citrate- treated southern yellow pine
2001 - IRG/WP 01-10388
Non-arsenical copper-based wood preservatives have grown in number since the 1980's as a response to environmental concerns posed by arsenicals. Interest in copper tolerant decay fungi has increased accordingly. Oxalic acid (OA) production by brown-rot fungi has been proposed as one mechanism of copper tolerance. Fifteen brown-rot fungi representing the genera Postia, Wolfiporia, Serpula,...
F Green III, C A Clausen
Fungi associated with groundline soft rot decay in copper/chrome/arsenic treated heartwood utility poles of Malaysian hardwoods
1992 - IRG/WP 92-1567
Copper-chrome-arsenic treated heartwood from Malaysian hardwood utility poles in service for 8-23 y at two localities in the wet tropical Peninsula Malaysia were surveyed for soft rot in the ground-contact region. Soft rot decay was detected in all the poles. Isolation studies indicated the ability of a variety of microfungi and basidiomycetes to colonize treated heartwood. Most isolates exhibited...
A H H Wong, R B Pearce, S C Watkinson
Copper-resistant fungi on pressure impregnated wood in Denmark
1994 - IRG/WP 94-10078
The occurence of Amorphotheca resinae Parbery and its asexual stage Cladosporium resinae (Lindau) de Vries on CCA and CCB treated wood has previously been shown. In the autumn 1993 some other blue stain fungi were found on CCP and CCB treated pine timber, such as Ophiostoma minus (Hedgc.) H. and P. Sydow, Ophiostoma pilifera (Fr.) H. and P. Sydow and Ophiostona piceae (Munch) H. and P. Sydow. The ...
J Bech-Andersen, S A Elborne
CCA modifications and their effect on soft rot in hardwoods. Part 2
1983 - IRG/WP 3244
The work outlined in this document is a continuation of that presented in Document No: IRG/WP/3201. The findings described in the previous paper are summarised below: a double treatment of CCB followed by arsenic (CCB+A) is more effective than a double treatment of boron followed by CCA (B+CCA) or a single treatment of CCA, CCB or CCAB in controlling soft-rot due to Chaetomium globosum in birch. C...
S M Gray, D J Dickinson
Susceptibility of CCB treated wood to fungal colonization
2003 - IRG/WP 03-10492
CCB treated wood is generally resistant to all wood decay fungi. However, like CCA impregnated wood, susceptibility of CCB treated wood to copper tolerant fungi have been observed. The ability of various brown rot fungal hyphae to penetrate and overgrow the wood samples was investigated. Samples made of Norway spruce (Picea abies) were impregnated with 5 % CCB solution according to the EN 113 proc...
F Pohleven, U Andoljsek, P Karabegovic, C Tavzes, S A Amartey, M Humar
Determination of absorption, accumulation and transport of copper in mycelium of some wood decay fungi
1999 - IRG/WP 99-10323
Copper compounds are common wood preservatives. However, tolerance of some wood decay fungi to copper compounds has been observed recently. Therefore, we tried to elucidate possible causes of this phenomenon. We investigated uptake, accumulation and secretion of copper in the mycelium of potentially copper tolerant fungi (Antrodia sp.) and non tolerant fungus Trametes versicolor. We observed that ...
F Pohleven, S Breznikar, P Kalan, M Petric
Degradation of lignin model compounds with coordinated copper in the presence of peroxide
1998 - IRG/WP 98-10282
A novel diffusible system capable of decomposing lignin model compounds with copper, coordinators and peroxides has been proposed. When pyridine was used as a copper coordinator, two synthetic dyes, Poly-R and RBBR were intensively decolorized with Cu(II) and H2O2 in aqueous solutions at room temperature. Although reactions with Cu(II) and H2O2 produce a strong oxidant, hydroxyl radical, via a Fen...
K Koller, K Messner, T Watanabe
Lignin degradation by a non-enzymatic system supposed to be active in white rot fungi
2000 - IRG/WP 00-10340
Electron microscopic investigations have shown that ligninolytic enzymes of white-rot fungi are only able to penetrate the wood cell wall in late stages of degradation. Thus, the selective degradation of lignin of certain white-rot fungi can only be explained on the basis of a low molecular weight, highly diffusible system. A system, consisting of copper, a coordination compound and either H2O2 or...
P Lamaipis, W Gindl, T Watanabe, K Messner
Tolerance of Wood Decay Fungi to Commercial Copper Based Wood Preservatives
2002 - IRG/WP 02-30291
Due to the use of copper based preservatives like CCB or CCA for more than a century, copper tolerant fungi have appeared in some European countries in recent times. It is therefore important to find out whether this phenomenon is specific for only classical copper ingredients, or generally for all copper based formulation. Thus, we tested the tolerance of three commercial copper based pres...
F Pohleven, M Humar, S A Amartey, J Benedik