Your search resulted in 189 documents. Displaying 25 entries per page.
Leaching characteristics, decay and termite resistance of treated wood with boron compounds, N'-N-(1,8-Naphthalyl) hydroxylamine (NHA-Na), and hydroxynaphthalimide (NHA-H)
2003 - IRG/WP 03-30307
Despite many advantages of boron wood preservatives, boron itself does not adequately protect wood in ground contact and exterior applications because its natural diffusibility and susceptibility to leaching. As a result of previous studies to limit or decrease boron leaching, several fixation systems have been developed. In this study, we evaluated the effects of N'-N-(1, 8-Naphthalyl) h...
S N Kartal, Y Imamura
Remedial treatments of glulam = diffusion of active ingredients through glue lines from solid wood diffusable preservatives
1996 - IRG/WP 96-30117
Diffusable preservatives are very suitable for use in remedial treatments of laminated beams in which too high moisture content involves the development of wood destroying fungi. The diffusion of active ingredients (boric acid, disodium octoborate, bifluoride) is well observed in solid wood but in a composite wood, the glue lines may appear not only as a barrier for the diffusion but also, may be ...
D Dirol, S Mouras
The probable mechanism of action of boric acid and borates as wood preservatives
1990 - IRG/WP 1450
The tetrahydroxyborate ion [B(OH)4-] acts by complexation with poly-ols and probably attacks decay fungi through extracellular substrate sequestration; intracellular substrate sequestration; enzyme inhibition; and change in membrane function. Work was carried out to investigate this further and to try to explain certain phenomena observed in the area of boron preservation. The effect of Na borate ...
J D Lloyd, D J Dickinson, R J Murphy
Biochemical relationships between biodegradation of cellulose and formation of oxalic acid in brown-rot wood decay
1991 - IRG/WP 1472
Non-enzymic hydrolysis of cellulose with low concentrations of oxalic acid was examined. The incubation of pine wood pulp with 1% oxalic acid (pH 1.3) at 35°C for 4 weeks reduced the original viscosity to 60%. Reducing sugars were liberated from various cellulosic samples by the oxalic acid treatment. However, crystallinities of cellulose in those samples did not change before and after the treat...
M Shimada, Y Akamatsu, A Ohta, M Takahashi
Laboratory screening to determine the preventive effectiveness against blue stain fungi and moulds
1991 - IRG/WP 3677
This paper reports results of preservative treatment and leaching experiments, using borax, polybor and boracol 20, on small wood blocks of English oak and American pitch pine heartwood. Earlier experiments on the performance of various biocides as possible additives to bilgewater to prevent fungal decay of shipping timbers had suggested that some formulations of boron might be associated with phy...
M T De Troya, A M Navarrete
Fungal remediation of CCA-treated wood
2004 - IRG/WP 04-50210
This study evaluates oxalic acid accumulation and bioremediation chromated copper arsenate (CCA) treated wood by three brown-rot fungi, Fomitopsis palustris, Coniophora puteana, and Laetiporus sulphureus and ten mold and staining fungi, Aspergillus niger, Aureobasidium pullulans, Gliocladium virens, Penicillium funiculosum, Rhizopus javanicus, Ceratocystis pilifera, C. peceae, Alternaria alternata...
S N Kartal, Y Imamura
Oxalic acid quantification, oxaloacetase assay and ESI localization of P, C, and Fe from the brown rot fungus Postia placenta
1994 - IRG/WP 94-10063
The mechanism by which brown-rot fungi initiate depolymerization of holocellulose in wood remains unknown. Recently, oxalic acid (OA) has received considerable attention in cellulose breakdown by brown-rot fungi. The OA could serve as a proton donor for hydrolytic or an electron donor for oxidative (Fenton's reaction-H2O2/Fe2+) cleavages of cellulose. The acid may originate via oxaloaceta...
C R Jordan, W V Dashek, T L Highley
Production of exraxellular hydrogen peroxide and oxalic acid by brown-rot fungus Poria placenta
1995 - IRG/WP 95-10112
Hydrogen peroxide and oxalic acid have been suggested to be essential in the degradation of wood carbohydrates by brown-rot fungi. Hydrogen peroxide has been suggested to be one of the diffusible low molecular weight agents produced by brown-rot fungi for the degradation of wood carbohydrates by generating highly active radicals. The production of hydrogen peroxide and oxalic acid by Poria placent...
A-C Ritschkoff, M Rättö, J Buchert, L Viikari
Composting of waste building up in sawmill dipping basins
1990 - IRG/WP 3570
We have studied composting of waste building up in dipping basins at sawmills although this waste can also be disposed of by incineration. Controlled composting within the sawmill area seems to be a feasible method. Another possibility is to accomplish composting directly at the local dumping site. Waste containing antistain chemicals is generally classed as hazardous. It cannot therefore be place...
I A Linderborg, U Ek
Steam/hold/APM boron treatment - Treatability trials with green gauged radiata pine
1987 - IRG/WP 3439
Freshly sawn 100 x 50 mm radiata pine was green gauged, steam conditioned and preservative treated with a mixture of borax and boric acid using a modified Alternating Pressure Method (APM) treatment schedule. A 12 hour holding period between steam conditioning and treatment resulted in the necessary moisture loss and moisture re-distribution to facilitate treatment to NZ Timber Preservation Author...
P Vinden
Preservative-efficacy of boric acid-triethanol amine solution against wood-decay fungi
1994 - IRG/WP 94-30050
Laboratory preservative-efficacy tests were conducted using boric acid-triethanol amine (BTEA) solution in accordance with the JIS A 9201 (1991) test method excluding the standard weathering process. Sapwood specimens of Picea jezoensis or Fagus crenata to achieve nominal retentions of 0.40-41.2 kg/m³ of boric acid were exposed to Tyromyces palustris, Coriolus versicolor, Serpula lacrymans or Cha...
S Doi, M Mori, Y Mineki
Remedial ground-line treatment of CCA poles in service. A final report after 60 months' testing
1989 - IRG/WP 3534
Remedial treatment of CCA treated utility poles of Pinus sylvestris with incipient decay was carried out in 1983 and the results of chemical and microbiological analyses 6 months after treatment were reported in Document No: IRG/WP/3388 while microbiological studies 12 and 28 months after treatment as well as chemical analyses of poles treated with boron rods or boric acid paste 28 months after tr...
B Henningsson, H Friis-Hansen, A Käärik, M-L Edlund
Estimation of oral toxicity of boron as a bait toxicant and the trophallactic effects between individual members of termite colonies.
2003 - IRG/WP 03-10495
In recent years, because of the favourable environmental characteristics of boron, researchers in the wood preservation industries have refocussed on the use of boron as a major wood preservative against wood-destroying insects. Currently the greatest use of boron compounds is in remedial treatments.
Boron has been found to have slow-acting toxicity against subterranean termites. Because of thi...
B M Ahmed
The use of propionic acid to prevent Pinus patula biodeterioration during outside chip storage in Zululand
1989 - IRG/WP 3531
Pinus patula SCHIEDE ET DEPPE IN SCHLD. ET CHAM. is susceptible to biodeterioration during outside chip storage (OCS), reducing pulp quality and tear and burst indices of resulting paper. Accelerated laboratory trials showed that chips treated with 2% (w/v) propionic acid and stored for 17 weeks, produced pulp of quality indistinguishable from fresh untreated chips. Pulp tests during field trials ...
S Ismail, E J Smith, A A W Baecker
Resistance of wood inorganic material composites against decay fungi and subterranean termites
1996 - IRG/WP 96-40062
Double diffusion process was applied to the treatment of small sound sapwood specimens [20(T) x 20(R) x 10(L) mm³] of Cryptomeria japonica D. Don. The specimens were consecutively dipped in the two kinds of acqueous solutions to form water insoluble deposits within the wood after an expected reaction between the solutes. Following the comparison of deposits formed and treating conditions (tempera...
K Tsunoda, T Yoshimura, M Takahashi, S Hirao, H Usui
Long term experiments for assessing the diffusion of boric acid and diluorides from local preservative pills in spruce and pine
1996 - IRG/WP 96-40065
For the experimental assessment of the diffusion of boric acid and difluorides over a three year period 2 tests were set up. In a test with large spruce blocks (150 x 150 x 300 mm³) 3 different pill types were exposed to 3 different climates: climate room (20°C, 65% r.h.), wet room (20°C, 95% r.h.), and to outside exposure. In a test with open L-joints without paint, with an alkyd paint and wit...
W J Homan, H Militz
An example of media response to perceived environmental problems with CCA-treated wood
1990 - IRG/WP 3564
A recent study suggested that CCA-treated wood exposed to acidic precipitation could lose significant amounts of copper chromium and arsenic resulting in loss of efficacy and possible environmental contamination. The study received wide newspaper and radio coverage in Canada, thereby heightening public concern about CCA use. Subsequent studies in our laboratory confirmed that the high losses were ...
P A Cooper
Preservative treatment of Golpata (Nypa fruticans) using CCA (Chromated Copper Boric Acid)
1999 - IRG/WP 99-40131
Golpata (Nypa fruticans) leaves provide a cheap but practical source of roof thatches. This study was carried out to determine whether the life span of Golpata could be extended by using CCB (Chromated Copper Boric Acid) treatment. Both leaves and midribs of Golpata , with different moisture contents ranging 16.63% to 70.67%, at the start of the experiment were treated with four different concentr...
G N M Ilias, F Abdullah, M O Hannan, S M Feroz
Hemicellulosic induction of oxalic acid in Postia placenta
1994 - IRG/WP 94-10060
Most studies suggest that enzymes produced by brown-rot fungi are too large to penetrate sound wood structures, even after decay begins. Thus, nonenzymatic agents have been proposed to initiate brown-rot decay. We have reported that the brown-rot fungus Postia placenta MAD-698 initiates a 2-fold decrease in wood pH within 7 days of colonization which is mediated by production of oxalic acid. Strai...
F Green III, M Larsen, T L Highley
Comparison of methods for monitoring CCA fixation
1994 - IRG/WP 94-40023
The CCA fixation status in the outer 12.5 mm of pole sections of southern pine (Pinus sp.), red pine (Pinus resinosa) and lodgepole pine (Pinus contorta var. latifolia) were followed during fixation at 21°C under non-drying conditions by the following procedures: - Qualitative CrVI indication by the chromotropic acid spot test. - Quantitative CrVI in the expressate by the diphenylcarbazide method...
P A Cooper, Y T Ung, G Zanjani
Effect of humic acid on leaching of CCA from treated wood
2000 - IRG/WP 00-50151
Laboratory studies indicate that relatively high concentrations (1.000 - 10.000 ppm) of humic acids can increase the leaching of chromium and copper from CCA-C treated wood, and that copper is most affected. They also show that leaching with natural water samples can result in higher leaching of all components than leaching with distilled water. Evaluation of CCA component retentions and mass bala...
P A Cooper, D Jeremic, J L Taylor, Y T Ung
The long road to understanding brown-rot decay. A view from the ditch
1995 - IRG/WP 95-10101
Interest in understanding how brown-rot fungi decay wood has received increasing interest in recent years because of a need to identify novel targets that can be inhibited for the next generation of antifungal wood preservatives. Brown-rot fungi are unique in that they can degrade holocellulose (cellulose and hemicellulose) in wood without first removing the lignin. Furthermore, they degrade holoc...
F Green III, T L Highley
Acceleration of boric acid uptake into the subterranean termite, Coptotermes formosanus Shiraki using steamed larch wood
2000 - IRG/WP 00-10353
Laboratory tests were done to measure the efficacy of addition of steamed larch (Larix leptolepis (Sieb. et Zucc.) Gord.) heartwood extracts for the uptake of boric acid against the termite, Coptotermes formosanus Shiraki. Paper discs were treated with the water-soluble fraction obtained from hot-water extracts of steamed larch wood (S-Water) with or without 0.01-2.0% boric acid, followed by expos...
W Ohmura, S Doi, S Ohara
Durability of heat-treated wood
1999 - IRG/WP 99-40145
Heat-treated wood from the French process were laboratory tested against decay using agar block test and a modified soil block test. Water absorption, bending strength, lignin content and acid number were also determined to evaluate the effect of heat treatment. Heat treated samples exhibit a higher lignin content and a lower acid number compared to untreated control indicating the degradation of ...
D P Kamdem, A Pizzi, R Guyonnet, A Jermannaud
Targeted inhibition of wood decay (Using everything but the kitchen sink)
1997 - IRG/WP 97-10203
Low molecular weight oxidative decay agents have been implicated in the degradation of wood by brown-rot decay as evidenced by chemical analysis of brown-rotted wood and detection of oxalic acid and hydroxy radicals. Fenton chemistry (H2O2 / Fe++) is often proposed as the mechanism for generating hydroxy radicals. Previous authors have shown iron to enhance the brown-rot hydrolysis of wood, while ...
F Green III, T A Kuster, T L Highley