Your search resulted in 220 documents. Displaying 25 entries per page.
Effect of a penta emulsion on the service life of Douglas fir, heartwood posts
1978 - IRG/WP 3112
C S Walters
Treatment of Douglas fir heartwood with disodium octaborate tetrahydrate (Tim-BorÒ ) to prevent attack by the Formosan subterranean termite
1991 - IRG/WP 1487
Toxicity of disodium octaborate tetrahydrate (Tim-BorÒ) to Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), and termite feeding on treated Douglas-fir heartwood were evaluated in laboratory and field tests. Feeding on filter papers impregnated with Tim-BorÒ solutions reduced but did not eliminate termite gut protozoan populations. In a forced-feeding laboratory assay, Douglas-fir hear...
M Tamashiro, R T Yamamoto, J K Grace
The effect of selective additives and conditions on the decomposition of Basamid in Douglas fir heartwood
1992 - IRG/WP 92-3698
Basamid is a solid, powdered chemical used as an agricultural soil fumigant. Decomposition of Basamid isothiocyanate, hydrogen sulfide, methyl amine, and formaldehyde. Basamid has some potential as a wood fumigant, but it decomposes too slowly to be effective. Various additives and conditions were tested for their ability to enhance Basamid decomposition in Douglas-fir heartwood. Higher MC&apo...
P G Forsyth, J J Morrell
Diffusion of a copper naphthenate/boron paste through Douglas fir heartwood
1991 - IRG/WP 3671
Groundline wraps are an important portion of the remedial treatment strategies for protecting utility poles in North America from surface decay. The compositions of these wraps have recently shifted away from pentachlorophenol and creosote to formulations containing copper naphthenate and boron. These formulations have not yet been extensively tested, although the chemicals have been used for many...
P G Forsyth, J J Morrell
The influence of wood moisture content on the fungitoxicity of methylisothiocyanate in Douglas fir heartwood
1987 - IRG/WP 3430
The fumigant methylisothiocyanate (MIT) effectively controls decay fungi in large wood structures, but the influence of environmental factors on its performance are not well understood. Experiments found wood moisture content to greatly influence the fungitoxicity and sorption of MIT in Douglas fir heartwood. At constant, low MIT vapor concentrations (less than 1 µg/cc air), wood at 10% MC bound ...
A R Zahora, J J Morrell
Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition
2003 - IRG/WP 03-40259
A limited understanding of the fundamental aspects of supercritical fluid (SCF) impregnation in wood remains an obstacle to the development of this technology. Developing a better understanding of the effects of various process parameters on treatment results would facilitate more rational development of SCF impregnation. In this project, the effect of treating period and specimen length on su...
Sung-Mo Kang, J J Morrell
A comparison between high and conventional incision densities for improving preservative treatment of Douglas-fir heartwood lumber
1993 - IRG/WP 93-40009
Incising is required for the preservative treatment of most wood species from the western United States; however, there is considerable debate about the density of incisions required to achieve adequate treatment. Previous studies have shown that the incision effect on treatment is relatively narrow, suggesting that incision densities should be significantly increased over current practices and st...
S T Lebow, J J Morrell
Potential for using dip/supercritical fluid treatments for wood impregnation
2004 - IRG/WP 04-40276
While supercritical fluid impregnation offers tremendous potential for impregnating wood species that resist conventional liquid preservative treatments, the resulting treatments are often not uniform among samples in a charge or between charges. One factor that influences treatment is the dynamic change in pressure that occurs during introduction of the biocide laden supercritical fluid into the ...
Sung-Mo Kang, J J Morrell
Development of threshold values for boron compounds in above ground exposures: Preliminary trials
1998 - IRG/WP 98-30179
Boron is increasingly used both as an initial and remedial treatment for protecting wood against fungal and insect attack. While establishing lethal dosages for boron against insects through feeding tests is relatively simple, establishing thresholds for fungal attack poses more of a challenge. Tests using boron dispersed in agar artificially surround the fungus with both boron and excess nutrient...
J J Morrell, C M Freitag, S Unger
Effects of chemical pretreatment of Douglas-fir heartwood on efficacy of potential bioprotection agents
1990 - IRG/WP 1440
Biological protection against wood decay fungi represents an environmentally attractive alternative to the use of chemicals; however, the process of identifying suitable candidates and the conditions that ensure successful protection pose major challenges. One critical aspect of this problem is to identify organisms that can rapidly and uniformly colonize the wood. Wood contains low levels of nutr...
B Dawson-Andoh, J J Morrell
Fixation and leaching characteristics of Douglas-fir treated with CCA-C
2004 - IRG/WP 04-50213
Fixation and leaching characteristics of CCA-treated Douglas-fir was evaluated using the expressate method and the AWPA E11-97 leaching procedure. CCA fixation, as monitored by the chromium reduction, was much faster in heartwood than in sapwood; however, copper and arsenic fixation in heartwood appeared to be incomplete regardless of the extension of fixation time. This poor fixation of copper a...
Gyu-Hyeok Kim, Yun-Sang Song, Dong-heub Lee
The effect of wood moisture content and rod dosage on movement of boron through Douglas-fir heartwood
2007 - IRG/WP 07-30431
The potential for moisture sorption by boron rods following application to wood to affect subsequent boron diffusion was investigated in small Douglas-fir blocks conditioned to 30, 60 or 90% moisture content (MC). MCs tended to decline over the 180 day test period, but there was no evidence that the rods acted to draw moisture away from the wood. As expected, boron movement tended to increase with...
Y Cabrera, J J Morrell
Effects of thermal modification on properties of Douglas-fir heartwood
2014 - IRG/WP 14-40663
The flexural properties and mass losses of thermal modified Douglas-fir pretreated with boron or glycerol were examined. Pretreatments were associated with slight, but not significant, reductions in modulus of rupture (MOR) and modulus of elasticity （MOE）of Douglas-fir at different thermal treatment levels. Boron pretreatment had the greatest effect on MOR. MOR of non-pretreated and ...
Li Yan, J J Morrell
Impact of sapwood portions on the durability of adjacent heartwood of Pinus sylvestris, Pseudotsuga menziesii and Quercus robur. Part 1: Laboratory studies
2018 - IRG/WP 18-10922
Sapwood is generally considered as non-durable and assigned to durability class DC 5 according to European standards independent from the wood species. It is commonly agreed that sapwood decays faster than adjacent heartwood, but it is controversially discussed whether sapwood serves as feeder material and thus accelerates onset and progress of decay in more durable heartwood or decays independent...
C Brischke, P Homann, A Gellerich
Application of radio frequency heating to accelerate fixation of CCA in treated round-wood
1999 - IRG/WP 99-40133
The potential of radio frequency heating to accelerate the fixation of chromated copper arsenate (CCA) in treated round-wood was assessed. Pre-dried Douglas-fir and western red cedar round-wood sections were pressure treated with CCA in a pilot plant retort, after which they were placed individually in a pilot radio frequency (RF) chamber. Based upon the color reaction of chromotropic acid with he...
Fang Fang, J N R Ruddick
The use of pressure cycling to improve heartwood penetration in Pinus radiata (D. Don)
1995 - IRG/WP 95-40050
This study investigates the effect of cycling pressure on the treatability of radiata pine heartwood. The results indicate that liquid penetration into the heartwood is affected by the preconditioning method used and pressure treatment time. There is no significant improvement in the penetration of Pinus radiata (D. Don) heartwood when a cycling or pulsation process is used....
P R S Cobham, P Vinden
Chemical compounds from Eperua falcata and Eperua grandiflora heartwood and their biological activities against wood destroying fungus (Coriolus versicolor)
2005 - IRG/WP 05-30373
The chemistry analysis of the compounds present in dichloromethane and ethanolic fraction as well as bioassays enables to understand the durability differences of Eperua falcata and Eperua grandiflora. The principal distinction between these two species is the acidic subfraction of diterpenoic extract, which is antifungic in Eperua falcata when tested in in-vitro conditions. This study also enable...
N Amusant, C Moretti, B Richard, E Prost, J M Nuzillard, M-F Thévenon
Treatability of plywood containing intermountain Douglas fir veneers
1982 - IRG/WP 3203
Eighteen sheets of plywood were obtained which contained intermountain Douglas-fir veneers from two regions of British Columbia. Following pressure treatment with chromated copper arsenate (CCA type C) and ammoniacal copper arsenate (ACA) the preservative penetration and retention in individual veneers was assessed. It was concluded from the study that the intermountain Douglas-fir veneer could no...
J N R Ruddick, A Walsh
An investigation of the effects of pre-steaming on the treatment of sawn spruce timber with Celcure A, a copper-chrome-arsenic preservative
1981 - IRG/WP 3150
Difficulties in the treatment of spruce using standard vacuum/pressure techniques with both water-borne and organic solvent preservatives are well known. We have evaluated the influence of steaming on treatability with a waterborne CCA preservative....
C R Coggins
Light organic solvent preservative treatment schedules for New Zealand-grown radiata pine
1986 - IRG/WP 3379
The influence of pressure differential and treatment time on preservative uptake and distribution in radiata pine heartwood and sapwood is investigated. Treatment schedules are defined which minimise solvent usage but ensure complete sapwood penetration and optimise heartwood penetration....
P Vinden
Possibility of use of wood species per class of biological risks. Attempt to determine criteria based on Pr EN 350-1/2/3
1992 - IRG/WP 92-2409
M Rayzal
Long-term effectiveness of fumigants in controlling decay in Douglas fir waterfront timbers
1986 - IRG/WP 3364
The persistence, movement, and effectiveness of chloropicrin and Vapam (sodium N-methyl dithiocarbamate) in large, horizontal Douglas fir timbers were evaluated 7 years after fumigation. Chloropicrin prevented reestablishment of decay fungi; reinvasion occurred in some Vapam-treated timbers. Residual fungistatic effect was detected up to 1.2 m from the fumigation site in chloropicrintreated timber...
T L Highley
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
Sequential exposure of borate treated Douglas-fir to multiple Formosan subterranean termite colonies in a 40-week field test
1993 - IRG/WP 93-10006
Douglas-fir boards (ca. 74.5 g) pressure-treated with disodium octaborate tetrahydrate (DOT) retentions of 0 (controls), 0.88, 1.23, 1.60, or 2.10% (weight/weight) DOT were sequentially exposed to four active field colonies of Formosan subterranean termites, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), in an above-ground field test. Samples were placed in contact with each colony fo...
J K Grace, R T Yamamoto
Efficacy of some extractives from Pinus heartwood for protection of Pinus radiata sapwood against biodeterioration. Part 1: Fungal decay
1995 - IRG/WP 95-30072
Chemical compounds thought to contribute to the natural durability of heartwood of Pinus spp. were either chemically synthesised in the laboratory or extracted from the heartwood of Pinus elliottii or Pinus caribaea. These compounds included the stilbenes, pinosylvin and its mono- and di-methyl ethers, and the flavonoids, pinobanksin and pinocembrin. Small blocks of Pinus radiata sapwood were impr...
M J Kennedy, J A Drysdale, J Brown