Your search resulted in 29 documents. Displaying 25 entries per page.
The influence of carrier fluid type on the efficacy of a wood preservative against cavity forming soft rot
2000 - IRG/WP 00-30244
Propiconazole was applied to Scots pine sapwood (Pinus sylvestris) and beech (Fagus sylvatica) using three different carrier systems selected on their varying ability to swell timber. The effects of microdistribution on the activity of cavity forming soft rot fungi were examined to determine the practical benefits of using swelling and non-swelling carriers with this active ingredient. Efficacy of...
P A Hodges
Hydrofluoroalkanes as carrier solvents for timber preservation
2009 - IRG/WP 09-40463
Hydrofluoroalkanes are a specific category of hydrofluorocarbon (HFC) commonly used in refrigeration applications. Some HFCs hold potential for use as carrier fluids for preservatives used to protect timber above ground. They do not share the most significant disadvantages of currently used carriers for these applications. At ‘conventional’ operating pressures, they are capable of rapid, full ...
M J Kennedy, B Walker, C Erskine
A review of the configuration of bordered pits to stimulate the fluid flow
2005 - IRG/WP 05-40315
As the bordered pits have generally been thought to have an influence on the refractory nature of softwoods, structural behaviour of this conducting pathways is discussed according to the published literature. Various theories on the role of bordered pits to axial flow are expounded in respect to preservative treatment. Pit aspiration is also reviewed....
I Usta
Direct measurement of fluid flow within wood
1986 - IRG/WP 2248
The problematics of fluid flow mechanism within wood using a permeability concept are highlighted, and the non-feasibility of a practical and versatile model is explained. An alternative method using a negative temperature coefficient thermistor to measure flow velocity directly is presented. The method has been verified in living trees and shows extreme sensitivity for flow above 1 meter/hour. Fo...
J P Hösli
Analysing the characteristic role of moisture content for drying and fluid flow in Sitka spruce. - Part 1: The drying process of sapwood and heartwood of two different thickness of Sitka spruce using a kiln. - Part 2: Effects of moisture content on longitudinal permeability of Sitka spruce in vertical variation of the tree
2000 - IRG/WP 00-40173
The characteristic role of the moisture content in Sitka spruce (Picea sitchensis (Bong.) Carr.) that grown in the United Kingdom was examined by this study on the basis of (1) the reduction of moisture content in two different thickness of sapwood and heartwood by kiln drying process, and (2) the effects of moisture content to the longitudinal void volume filled of tanalith-C by the full-cell pro...
I Usta
Alternative technologies for wood wastes recycling - Part B: Biotreatment of PCP- and creosote-treated wood
1998 - IRG/WP 98-50101-18 b
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
S Legay, P Marchal, G Labat
Bending properties of TCMTB-treated Southern pine sapwood using supercritical carbon dioxide impregnation process
1997 - IRG/WP 97-40080
The effects of elevated pressure and treatment with thiocyanomethylthiobenzothiazole (TCMTB) on the bending properties of Southern pine sapwood were evaluated at pressures ranging from 1,800 to 3,600 psi. All bending properties were affected to some extent by supercritical fluid treatment. Modulus of elasticity and work to maximum load were not significantly affected by pressure levels. Modulus of...
Gyu-Hyeok Kim, S Kumar, E S Demessie, K L Levien, J J Morrell
Effects of seed origin and site on both wood density and longitudinal fluid uptake of Sitka spruce (Picea sitchensis (Bong.) Carr.) with height in the tree grown in the United Kingdom
2002 - IRG/WP 02-40226
The variation in density and longitudinal fluid uptake was investigated in short specimens of wood taken from eight seed origins of Sitka spruce trees grown at two sites in the UK. Five trees of each seed origin at each site were sampled at three heights (1, 2 and 3 m above ground
level). The density of the samples decreased with increasing height within the stem. This corresponded with increasin...
I Usta, M D C Hale
Trial to determine a suitable schedule for radial and longitudinal treatment of plug samples by comparison of changes in the fluid retention and the treated area
2001 - IRG/WP 01-40211
A full-cell process was carried out using different treatment schedules for radial and longitudinal samples because of the anisotrophy of flow. When timbers are impregnated with preservatives much better penetrations are obtained via the end grain than laterally (across the grain). Therefore, suitable schedules for radial and longitudinal flow directions were determined in an trial experiment usin...
I Usta
Cellular and fractural failure after supercritical fluid impregnation of four wood species
2004 - IRG/WP 04-10503
Supercritical fluids (SCFs) have been investigated for delivering biocides into sawn wood. Pressure differentials during treatment may exceed the compressive or tensile strength perpendicular to grain, creating a potential for transverse deformations that exceed elastic strain limits. Wood treated by SCF processing with CO2, a potential biocide carrier, was inspected macroscopically and microscopi...
M E Anderson, R J Leichti, J J Morrell
Penetration and distribution of styrene in pressure treated hardwoods
1997 - IRG/WP 97-40094
A styrene impregnation method was used to compare liquid distribution in several species as affected by flow direction, sapwood/heartwood, and method of impregnation. Twenty-five mm ( 1") cubes were cut from the sapwood and heartwood of red maple (Acer rubrum), white birch (Betula papyrifera), yellow poplar (Liriodendron tulipifera), trembling aspen (Populus tremuloides), red oak (Quercus rubra), ...
P A Cooper, T S Janezic, U Srinivasan, A Omidvar
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
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Alternative technologies for wood wastes recycling - Part A: Supercritical extraction of PAH compounds from wood wastes
1998 - IRG/WP 98-50101-18 a
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
L Schrive, C Perre, G Labat
Controlled envelope treatments of Pinus sapwood, achieved by modifications to impregnation process and carrier solvents
2003 - IRG/WP 03-40258
Specimens of slash pine or radiata pine were treated to a target retention of 0.02% m/m permethrin with conventional light organic solvent fluids or with oil-modified fluids (Tanalith® T). Best achievable envelopes from LOSP fluids were poorly controlled, penetrating not only the target outer 0-5 mm zone (mean 0.019%, RSD 28%), but also breaking through into the 5-10 mm zone (mean 0.013%, RSD 37%...
M J Kennedy, P R S Cobham
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
Preservative treatment of wood-based composites with a mixture formulation of IPBC-silafluofen using supercritical carbon dioxide as a carrier gas
2003 - IRG/WP 03-40251
Wood-based composites treated with a mixture formulation of a fungicide, 3-iodo-2-propynyl butylcarbamate (IPBC) and a termiticide, silafluofen using supercritical carbon dioxide (SC-CO2) as a carrier solvent were tested for their resistance to decay and termite attack in the laboratory. The treatment solution was prepared by mixing both biocides (IPBC 10 + silafluofen 1) with a co-solvent, ethano...
K Tsunoda, M Muin
A novel chemical barrier system, KORDON® TMB, for the protection of buildings against subterranean termites using a synthetic matrix as carrier for the chemical
1998 - IRG/WP 98-10264
Kordon TMB is a new chemical barrier system for installation beneath concrete slab-on-ground constructions using a matrix other than soil as carrier for the termiticide. The product consists of a synthetic foraminous web (blanket) carrying the synthetic pyrethroid deltamethrin. The blanket is laminated on the upper side to a standard 0.2mm thick moisture vapour membrane of low density polyethylene...
M Lenz, P Morrow, S Runko
Methods for improving preservative penetration into wood: a review
2002 - IRG/WP 02-40227
Pressure treatment technologies have been available since the mid-1830's, but the processes used for wood treatment are still largely unable to overcome the fundamental limitations of flow through semi-permeable pit membranes. Instead, methods have arisen that attempt to improve treatability of the wood including incising, compression rolling, through boring, or radial drilling. Other a...
J J Morrell, P I Morris
Performance of Oriented Strandboard, Medium Density Fiberboard, Plywood, and Particleboard Treated with Tebuconazole in Supercritical Carbon Dioxide
2005 - IRG/WP 05-30364
The performance of oriented strandboard (OSB), medium density fiberboard (MDF), particleboard and plywood treated with tebuconazole using supercritical carbon dioxide was investigated over a 48 month exposure under harsh above ground conditions in Hilo, Hawaii. Samples treated to low retentions (<0.20 kg/m3) tended to experience decay at rates that were only slightly lower than those found wit...
J J Morrell, M N Acda, A R Zahora
Evaluation of fluid distribution in pressure treated wood in different flow directions
2004 - IRG/WP 04-40281
Among different methods, polymerization technique was chosen to study distribution of fluid through cell types in treated wood. Red maple wood specimens with the size of 2 by 2 by 4 cm (radial, tangential and longitudinal, respectively) were prepared. Styrene monomer was used as the fluid for impregnation; because its physical properties such as surface tension, specific gravity and viscosity fall...
A Omidvar, M H Schneider
Internal pressure development within Oriented Strand Board during supercritical fluid impregnation
2000 - IRG/WP 00-40175
Supercritical fluids (SCF) offer an attractive alternative to conventional treatment processes for delivering material into wood, but there are many unanswered questions concerning the technology. One major concern is the potential for the development of excessive pressure gradients in the wood that might exceed the material properties and lead to crushing or other pressure-induced damage. Previou...
G Oberdorfer, P E Humphrey, R J Leichti, J J Morrell
Efficacy of Avermectin B1 dust and bait formulations in new simulated and accelerated field tests
1985 - IRG/WP 1257
Avermectin B1 on a silica carrier dust was used in dust and bait formulations whose efficacy against Reticulitermes flavipes was assessed in new simulated and accelerated field tests. A 0.5 mg avermectin/mg dust and a bait with 50 ppm avermectin in paper pulp sandwiched between pieces of corrugated boxboard caused nearly complete mortality in bioassays and suppression of foraging in field tests. T...
G R Esenther
Development of preservative treatment method using sub and super critical carbon dioxide
2007 - IRG/WP 07-40385
Significant efforts have been devoted for developing biocide impregnation method into wood materials using supercritical fluid. Developing better understandings of fluid phase and its effect on treatment results would facilitate a more rational development of supercritical fluid (SCF) impregnation. In this project, the preservative treatabilities under super- and sub-critical fluid conditions we...
Myeung-Won Cho, Sung-Mo Kang, Gyu-Hyeok Kim
Comparison of permeability at different levels of moisture content in Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) impregnated under vacuum/pressure through full-cell method by using CCA and CCB of different concentrations
2007 - IRG/WP 07-40366
In this study, a comparison has been made in terms of the combined, longitudinal, tangential, and radial permeability of the species of Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) with moisture contents of 50 % and 15 %, which were impregnated under vacuum/pressure through full-cell method by using water-borne wood preservatives (impregnation materials)...
I Usta