Your search resulted in 134 documents. Displaying 25 entries per page.
A combined method for drying and preserving wood in a single step process
2000 - IRG/WP 00-40183
Based on a convective dryer, this process allows to dry and treat wood blocks with diffusible preservatives in the same time. A boric acid solution (heated to fix the wet temperature of the system) is pumped and introduced in the flow system through a venturi, where the air coming back from the drying cell also arrives. The role of the venturi is to create a dispersion of boric acid solution micro...
O Colin, C Dupuis, E Mougel, A Zoulalian, M-F Thévenon
Survey of North American practice in conditioning forest products before preservative treatment
1972 - IRG/WP 308
Seasoning requirements for the wide range of forest products which are treated with preservatives and fire retardants must be capable of dealing with a very complex set of conditions which are summarized under a number of variables including type and hazard of end use, the most effective distribution of preservative, a wide range of cross sectional dimensions, the possibility of seasoning by a ran...
J Rak, T S McKnight
Changes in transverse wood permeability during the drying of rimu and radiata pine
1990 - IRG/WP 3636
When softwoods are dried and subsequently impregnated with waterborne preservatives two problems frequently occur, preservative screening of multi-salt preservatives and difficult re-drying. To study the causes, the permeability of rimu and radiata pine wood has been measured along the three principal directions. The radial and tangential permeabilities of the green sapwood of the two species were...
R E Booker
Partial seasoning and preservative treatment systems for pine roundwood
1982 - IRG/WP 3187
Experimental trials at FRI, Rotorua showed that the steaming schedule normally used for steaming and venting is also suitable for steaming and vacuum seasoning. Applying vacuum of up to -84 kPa immediately after steaming did not increase the initial loss of wood moisture significantly in comparison to steam/venting. The main improvement to wood condition by using steam/vacuum appeared to be to dis...
A J Bergervoet
Survey of practical methods for conditioning of forest products before preservative treatment
1971 - IRG/WP 39
The seasoning of forest products is undertaken for a wide range of end uses and is becoming increasingly required for applications and building construction and secondary manufacturing industries. A wide range of applications of new technology and specifically required seasoning schedules is being actively developed for such requirements, but less attention has been given to the means by which woo...
J Rak, T S McKnight
Wood preservation sites polluted by CCA. Is potassium diphosphate incubation a catalyst for the electrodialytic remediation of these soils?
1998 - IRG/WP 98-50106
As part of an evaluation of a newly developed electrodialytic soil remediation technique, we investigated the incubation of a contaminated soil (from a Portuguese wood preservation site polluted with CCA) with potassium diphosphate as a possible catalyst for the removal of heavy metals and metalloids. A chemical sequential extraction scheme (SE) applied to the soil has shown that the potassium dip...
A B Ribeiro, G Bech-Nielsen, A Villumsen, A Réfega, J Vieira e Silva
The influence of cement and calcium compounds on the performance of CCA preservatives
1983 - IRG/WP 3221
The influence of cement and calcium compounds on the durability of untreated and CCA treated wood is considered. Calcium compounds were found to reduce the toxicity of a CCA preservative to a soft rot fungus at copper to calcium ratios of 1:1 and 1:10 using a cellulose filter paper technique. Further studies are outlined and some possible mechanisms by which cement and calcium compounds may affect...
R J Murphy
The effect of chitosan on the growth and physiology of two wood inhabiting fungi
2006 - IRG/WP 06-10590
The effect of chitosan on the wood inhabiting fungi Sphaeropsis sapinea and Trichoderma harzianum was evaluated at cellular level. Increasing concentrations of chitosan caused an increase in the amount of peroxide in cultures of S. sapinea, which was accompanied by a simultaneous decrease in superoxide. The same effect was not observed in T. harzianum. The growth of both fungi was inhibited when h...
D Vesentini, T Singh
Vacuum drying of European oakwood: Color, chemistry and anti-oxidant potency of wood. Improving appearance in forest value added products
2008 - IRG/WP 08-40432
In hardwoods used for decorative and appearance purposes, wood colour is one of the most important factors of wood quality; in addition colour is related with durability and biological decay of wood. Wood discolouration during drying is mainly affected by heat, light, physiological reactions, combinations of reactions, biochemical and chemical reactions, and micro-organisms attack. In freshly fell...
S Sandoval, W Jomaa, F Marc, J-R Puiggali
Tensile stress relaxation of wood impregnated in different ACQ formulations at various temperatures
2009 - IRG/WP 09-40456
The reactions between ammoniacal copper quat (ACQ) constituents and wood components were investigated by tensile stress relaxation approach. Small wood samples were stressed and impregnated in ACQ solutions with different formulation including the ethanolamine (MEA) to copper molar ratio, copper (as copper oxide) to quat (as DDAC) weight basis, treatment temperature and also the solution concentra...
Lili Yu, Jinzhen Cao
Drying Rates and Mold Growth on Various Building Materials under Different Environmental Conditions
2010 - IRG/WP 10-20454
Mold growth on building materials is a major problem for homeowners. The most suitable method to control mold growth on building materials is to utilize design features, construction tools and practices that prevent moisture accumulation, and keep the wood as dry as possible. In order to achieve this, engineers and homebuilders have to know the effects of various temperature and moisture conditi...
Dian-Qing Yang
Studies on Effect of pH on Copper Availability in Copper-Based Preservatives
2010 - IRG/WP 10-30549
Laboratory methods have been employed to investigate the pH effect on the copper solubility of basic copper carbonate. The pH was controlled using two different approaches. One was with the adjustment of pH of the solutions by acid or base using sulfuric acid or sodium hydroxide until the solution equilibriums were obtained for each defined pH. A second approach was to control pH with buffer sol...
L Jin, P Walcheski, A F Preston
Influence of Copper Preservative Type on Earlywood and Latewood Distribution of Copper in Treated Wood
2010 - IRG/WP 10-40507
Some of the new water based copper containing wood preservative systems use particulate “micronized” copper as the primary biocide instead of the more traditional soluble amine copper based systems. Studies were conducted to investigate how this difference in the type of copper system might impact both initial and post drying distribution of the preservatives in wood. Of specific interest wa...
A Zahora
Chapter 11 - Preservation of talla bamboo
2007 - IRG/WP 07-10635-11
Researches revealed that the talla bamboo (Bambusa tulda Roxb.))
in Bangladesh could be full-cell pressure treated with CCA in green
and dry conditions. The dry bamboo gives higher loading
absorptions than green one when impregnated at same treating
conditions. Also higher absorptions are obtained at nodes rather
than internodes. Adequate penetration and retention results for
ground and wate...
A K Lahiry
Chapter 12 - Treatment Groups of Bamboo
2007 - IRG/WP 07-10635-12
Study on distribution of CCA in three major bamboo species in
Bangladesh, full-cell pressure treated at green and dry conditions
revealed two treatment groups and some treating principles. Higher
adequate treatment for ground and water contact use is only
possible by treating problematic bamboo species pre-kiln dried up to
half of its FSP and non-problematic species pre-dried up to FSP
(20% ...
A K Lahiry
Chapter 14 - Accelerated fixation of CCA-treated bamboo
2007 - IRG/WP 07-10635-14
Chromated copper arsenate type C (CCA-C) fixation study on
impregnated (with adequate w/v 6% CCA solution) then boiled,
oven-dried, normal, air-dried and steamed bamboo slices of airdried
borakbamboo (Bambusa balcooa Roxb.) of Bangladesh,
revealed almost complete fixation in steamed (accelerated fixation)
and air-dried (3 weeks, slow fixation) bamboo slices compared to
moderate to low fixati...
A K Lahiry
Theoretic discussion on the way and driving forces of moisture migration in wood during vacuum drying
2011 - IRG/WP 10-40538
Most of parameters in conventional drying cannot explain a lot of phenomena appeared in vacuum condition, so it is necessary to further explore the moisture migration way and driving forces in wood under vacuum condition. For the water movement channel in wood is very narrow, the characteristic of heat and mass transfer in wood is similar to that in microscale. This article applies theory of liqui...
Zhengbin He, Xueli Yao, Liqiong Chen, Songlin Yi
Multilayer hot-press drying and chemical modifying of poplar wood with urea-formaldehyde prepolymer
2011 - IRG/WP 10-40539
The objective of this study was to determine the technology of chemical modifying and multilayer hot-press drying on poplar wood. The chemicals were impregnated into cell lumen space by pulse-dipping machine to improve the dimension stability and mechanical property of timber. The timbers were compressed and dried by the multilayer hot-press drying to increase the density of timber. Results indica...
Guofeng Wu, Yifei Jiang, Sheng Yao, Junwen
Evaluation effect of kiln schedule on Warp, Twist, Bow and surface checks in Poplar Wood
2011 - IRG/WP 11-40565
In this research, to establish a kiln-drying schedule for poplar (Populus nigra) lumber with 75 mm thickness that cut down from North Khorasan province in Iran, with three schedules T5-D2 (Forest Product Laboratory), T5-D3 and T8-D5 were adapted for drying the lumbers down to the final moisture content of 8±2%. primary dry bulb temperature each three schedules was adjusted at 49,49 and 54°C and ...
M. Akhtari, M.Arefkhani
Characterizing long term leaching behaviour of copper from preservative treated wood in a practical exposure scenario
2011 - IRG/WP 11-50278
To investigate the prediction of the long term emission of copper from preservative treated wood in a Use Class Class 3 scenario, treated boards were exposed vertically above ground to natural weather conditions. The study included two products; an amine copper ACQ-type formulation, air-dried after treatment to a 22 kg/m3 retention, and the same formulation which was hot oil vacuum dried after tre...
T Mark Venås, M Klamer
Copper Migration from Micronized Copper Preservatives Treated Wood in soil contact:
2011 - IRG/WP 11-50280
Emerging formulations of preservatives made with micronized basic copper carbonates with azoles and/or quat to control copper tolerant fungi have been used to replace formulations containing soluble copper to reduce the leaching of copper and the corrosion of metal in contact with wood. This study proposes to use laboratory soil leaching test AWPA standard (E20-08) to estimate the amount of copper...
Lei Wang, D P Kamdem
The activity of a wood-decaying fungus during drying and rewetting cycles measured by isothermal calorimetry
2013 - IRG/WP 13-20526
Wood decaying fungi are an essential part of any ecosystems as they are the main decomposers of cellulose and lignin-containing materials. But as wood is a common building material the risk for decay fungi growth and subsequent degradation of our construction material is a concern. There are important physiological aspects of the growth and activity of decay fungi that are unknown today, and witho...
S Johansson, L Wadsö, A Pilgård, G Alfredsen
Comparison of moisture loss and its increment during the rehearsal process based on natural drying and water soaking application with or without sealing the trial discs of Common black poplar (Populus nigra L.)
2013 - IRG/WP 13-40639
This study was subjected to be set up to prove the pattern of moisture loss and moisture increment within the same wood samples prepared as the discs (30x23±3 cm diameter) with or without the bark intact during drying and in the duration of the water soaking application. In this concept, wood was exemplified by Common black poplar (Populus nigra L.) of the five 12 year old trees that are grown in...
I Usta
A screening of factors that might influence the result of laboratory decay tests
2014 - IRG/WP 14-20548
Laboratory fungal decay tests provide important tools for performance testing of wood materials. But they are also hampered with some uncertainties regarding reproducibility. In addition to variation between fungal species and strains the test conditions are also believed to have some influence. The aim of this study was to screen the effect of a selection of test parameters that might influence t...
E Larnøy, G Alfredsen, A Treu, S Kolstad
The effect of UV irradiation on some technological properties of different polyurethane varnishes coated plywood panels from veneers dried at different temperatures
2014 - IRG/WP 14-40661
In this study, the effect of UV irradiation on some technological properties of three different polyurethane varnishes coated plywood panels produced from Scots pine (Pinus sylvestris L.) and Maritime pine (Pinus pinaster L.) veneers manuactured and dried at different temperatures was studied. Accordingly, 32°C log peeling temperature and three different veneer drying temperatures (110, 140 and ...
Ö Özgenç, C Demirkir, Ü C Yildiz, G Çolakoğlu