Your search resulted in 189 documents. Displaying 25 entries per page.
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
CCA removal from treated wood by chemical, mechanical and microbial processing
1998 - IRG/WP 98-50101-26
Most preservative-treated wood produced and consumed in the U.S. is treated with toxic inorganic compounds containing copper, chromium, and arsenic. Because chromated copper arsenate (CCA) is fixed to the wood, treated wood has not been considered toxic or hazardous and is currently landfilled. Increasing public concern about environmental contamination from treated wood combined with increasing q...
C A Clausen, R L Smith
A physiological role of the glyoxylate and TCA cycles in fruitbody formation of the coppertolerant brown-rot fungus Fomitopsis palustris
2002 - IRG/WP 02-10430
Changes in activity of the representative enzymes involved in biosynthesis of oxalic acid (oxalate) and carbon metabolism of glucose were investigated in relation to the fruit body formation of the copper-tolerant brown-rot fungus Fomitopsis palustris. Changes in specific activities of the two glyoxylate (GLOX) cycle key enzymes (isocitrate lyase (ICL) and malate synthase (MS)), the two oxalate-fo...
Jeong-Jun Yoon, T Hattori, M Shimada
The role of oxalic acid in short fiber formation by the brown-rot fungus Postia placenta
1993 - IRG/WP 93-10028
The mechanism by which brown-rot fungi depolymerize wood and cellulose remains a perplexing problem. Current evidence favors oxidation by low-molecular weight, non-enzymatic fungal metabolites. During attack of cotton cellulose by Postia placenta MAD-698, the degree of polymerization (DP) decreases to limit of degree of polymerization (LODP) over a period of 5-6 weeks with relatively low weight lo...
F Green III, J M Hackney, C A Clausen, M J Larsen, T L Highley
The role of oxalic acid in tolerance to N’N-naphthaloylhydroxylamine in Tyromyces palustris
2006 - IRG/WP 06-10584
Certain wood decay fungi exhibit tolerance to one or more wood preservatives. Copper tolerance of brown-rot fungi has been studied in our laboratory for the past six years. We have observed some degree of tolerance to N’N-naphthaloylhydroxamine (NHA), a recently patented termite bait, by the brown-rot fungus Tyromyces palustris TYP-6137. In an effort to try and confirm this tolerance in other is...
R A Arango, C A Clausen, F Green III
Thermochemical Remediation of Preservative-Treated Wood
2008 - IRG/WP 08-50254
Remediation methods continue to be developed and refined for CCA-treated wood in order to divert this material from landfills and create secondary products from the wood fiber. A two-step thermochemical remediation method was developed to assess the efficiency of metal removal from CCA-treated spruce flakes. Nearly all the metals (As, Cr, and Cu) were thermochemically extracted from chromated copp...
R Sabo, C A Clausen, J E Winandy
Chemical mediated depolymerization of cotton cellulose for the understanding of non-enzymatic fungal decay
2010 - IRG/WP 10-10731
Small, low molecular weight non-enzymatic compounds have been linked to the early stages of brown rot decay as the enzymes involved with holocellulose degradation are found to be too large to penetrate the S3 layer of intact wood cells. The most pronounced of these which were analyzed in this study are hydrogen peroxide, iron, and oxalic. The compounds related to the Fenton reaction: the combinati...
A C Steenkjær Hastrup, B Jensen, F Green III
Optimization of oxalic acid production for bioleaching of metal components from CCA-treated wood by an unknown Polyporales sp. KUC8959
2010 - IRG/WP 10-50266
A brown-rot fungus, an unknown Polyporales sp. KUC8959, has recently been identified and proven as a prominent fungal species for bioremediation of CCA-treated wood wastes in our Lab. The fungus produced a larger amount of oxalic acid than other fungi tested, and removed 90 % or more of chromium, copper and arsenic from CCA-treated wood sawdust through bioleaching process. The bioleaching process ...
Yong-Seok Choi, Min-Ji Kim, Jae-Jin Kim, Gyu-Hyeok Kim
Fungal biodegradation of CCA-treated wood wastes
2011 - IRG/WP 10-50276
Fungal biodegradation could be employed as a pretreatment method to alleviate problems caused by landfill disposal of CCA-treated wood wastes (e.g. a shortage of landfill space and a release of leacheate). It could be used to decrease the volume of waste and to remove metals from waste simultaneously. We have screened hundreds of decay fungi, including fungi isolated from CCA-treated wood in servi...
Gyu-Hyeok Kim, Yong-Seok Choi, Jae-Jin Kim
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
Synergistic effect of boron on Streptomyces rimosus metabolites in preventing conidial germination of sapstain and mold fungi
1992 - IRG/WP 92-1565
We evaluated the synergistic effect of boron (4% BAE solution of Tim-Bor or 4% boric acid) on Streptomyces rimosus metabolites in preventing spore germination of sapstain and mold fungi using plate bioassay, Southern yellow pine and sweetgum block tests, and green pine log sections: sapstain -- Ceratocystis coerulescens, Ceratocystis minor, and Aureobasidum pullulans; mold fungi -- Aspergillus nig...
S C Croan, T L Highley
Response of the Formosan Subterranean Termite (Coptotermes formosanus) to Cellulose Insulation Treated with Boric Acid in Choice and No-Choice Tests.
2004 - IRG/WP 04-10532
The tunneling ability of the Formosan subterranean termite Coptotermes formosanus Shiraki through a cellulose insulation material containing11.1% boric acid was tested in choice and no-choice bioassays. We examined tunneling behavior and mortality of termites exposed to treated and untreated insulation material in miniature simulated wall voids. In a choice test termites tunneled through untreat...
M E Mankowski, J K Grace
Boron treatments for the preservation of wood - A review of efficacy data for fungi and termites
1994 - IRG/WP 94-30037
Boron treatments have been used for many decades for protection of timber from biological attack and also as a fire retardant treatment. In recent years there has been an increased interest in boron treatments as an option for protection of structural timbers' e.g. timber framing used in termite risk areas. This paper reviews efficacy data for both fungi and termites relevant to this end-...
J A Drysdale
Preliminary results of investigations on screening test of chemical compounds suitable for the preservation of lignocellulosic materials against biodeterioration
1976 - IRG/WP 262
This paper investigates the possibilities of reducing the time needed for the determination of the effectiveness of chemical compounds from the point of view of their eventual application to lignocellulosic materials for preservation against decay and soft-rot....
K Lutomski, S S Neyman
Patent on the use of tannic acid and ferric chloride against marine borers, etc
1982 - IRG/WP 495
R Mitchell, T D Sleeter
The influence of boric acid on respiratory quotients and methane production of subterranean termites
1995 - IRG/WP 95-10136
The toxicity of boron compounds to subterranean termites (Reticulitermes lucifugus) was studied by analysing changes in the levels of oxygen uptake respiratory quotients and methane production. Termites were fed with filter paper treated at different levels of boric acid, the RQ was evaluated by constant volume manometry and the methane production by gas chromatography. Results are discussed in re...
L Nunes, D J Dickinson
Comparative investigations on the influence of wood seasoning, wood properties and temperature on the toxic values of wood preservatives against Hylotrupes egg larvae
1970 - IRG/WP 28
Comparative tests carried out at three institutes indicated the influence of kiln temperature, position of wood specimens in the cross sectional area and test temperature on the toxic values determined in accordance with DIN 52165 with egg larvae of the house longhorn beetle (Hylotrupes bajulus L.). The preservatives applied were boric acid in distilled water and g-benzene-hexachloride dissolved i...
G Becker, T Hof, O Wälchli
Options for accelerated boron treatment: A practical review of alternatives
1985 - IRG/WP 3329
Boron wood preservatives are almost exclusively applied by momentary immersion and block diffusion storage. Alternative techniques are described which can be used to accelerate boron treatment. Diffusion coefficients have been derived to define the acceleration of diffusion with increasing temperature. Schedules are described for pressure impregnation of green timber, involving steam conditioning,...
P Vinden, T Fenton, K Nasheri
Movement of boron from fused boron rods implanted in Southern pine, Douglas fir, red oak, and white oak timbers
1995 - IRG/WP 95-30061
This paper reports the distribution of boron from fused boron rods installed into six-inch (15.2 cm) square timbers of Douglas-fir, Southern Pine, red oak and white oak exposed aboveground. The composition and size of rods was: sodium borate and sodium borate-copper oxide (8.5 x 100 mm²); sodium borate-copper, sodium borate and boric oxide-copper oxide (12 x 76 mm²). The boric acid equivalent wa...
T L Highley, L Ferge
A new approach to the maintenance problems of wooden railway sleepers
1986 - IRG/WP 3392
The microenvironment of wooden railway sleepers is being investigated to assess their condition to determine the necessary treatment, repair and replacement criteria. The research work involves the development of an integrity tester to determine the condition of sleepers, a remedial treatment of sleepers by selective application of boric acid and a synthetic repair system....
W Beauford, P I Morris.
Diffusion treatment plants (Latin America - Africa)
1974 - IRG/WP 333
B N Prasad
A field test with Benzotar, an industrial residue, as a wood preservative
1985 - IRG/WP 3349
Benzotar, a residue of production of benzoic acid, was tested in field as a wood preservative. Results, after 6.5 years of exposure, showed that this product presents properties that improve the performance of wood in ground contact. This paper describes these results and presents a discussion an some aspects of its potential utilization in Brazil....
S Milano, L R Silva
CCA fixation experiments. Part 2
1989 - IRG/WP 3505
CCA fixation in wood was measured by both squeezing solution from treated wood that had not been dried and analyzing the solution for copper, chromium and arsenic, as well as using a chromotropic acid test to detect the presence of chromium VI. Both methods provide useful information on the CCA fixation process and illustrate that chromium VI disappears as CCA becomes fixed within wood....
W S McNamara
Testing of alkylammonium compounds
1981 - IRG/WP 2152
Following laboratory soil block tests which showed that Bardac 20 possessed a fungicidal threshold similar to that of chromated copper arsenate, treated ponderosa pine sapwood stakes were installed in a field test site near Vancouver, Canada. Two years after installation all the stakes show signs of fungal degradation. Seven stakes have been removed from the test due to total loss of strength afte...
J N R Ruddick
In-situ pressure injection for preservation of rubber wood (Hevea brasiliensis Muel Arg.)
1992 - IRG/WP 92-3688
Rubber wood is widely used for the manufacture of furniture, doors for housing and packing cases. However in an untreated condition it is highley susceptible to sapstain and decay fungi and borers. Its utility gets considerably reduced if the wood is not treated well in time. Preservative treatment has to be given within the period of felling and transport to prevent not only loss of structural pr...
H S Ananthapadmanabha, V R Sivaramakrishnan