Your search resulted in 83 documents. Displaying 25 entries per page.
Effect of vapour boron treatment on mechanical properties of wood based board materials
1992 - IRG/WP 92-3727
The mechanical properties of Medium density fibre board, Chipboard and Oriented strand board were investigated after treatment to two retention levels of boric acid applied as a vapour phase system. A range of mechanical properties were investigated. The vapour boron treatment does not have any significant effect on most of the mechanical properties of the boards. The exception is a reduction in i...
R Hashim, D J Dickinson, R J Murphy, J Dinwoodie
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 6: The length of the primary precipitation period
1975 - IRG/WP 359
The end of the primary precipitation fixation period of CCA preservatives coincides with the first peak in pH versus time. This offers a simple way of estimating the duration of the period. The duration is determined by a number of factors and their interactions, the most important of which are: wood species (anatomy, natural pH, accessibility of reducing agents), preservative type, preservative c...
S-E Dahlgren
Effect of some resin treatments on fungal degradation reactions
1999 - IRG/WP 99-10318
The effect of impregnation of wood with vegetable oil, tall oil and two water soluble on fungal degradation reactions was assessed by hydrolysis and enzyme activity measurements. The experiments were carried out by using isolated enzyme preparations and a living brown-rot fungus Poria placenta. The results indicate that the inhibitory effect of treatments was clearly directec towards the enzymatic...
A-C Ritschkoff, M Rättö, A J Nurmi, H Kokko, A O Rapp, H Militz
Serial techniques for producing fire-retardant wood products
1997 - IRG/WP 97-30127
A series of techniques including fire-retarders denoted by WFR-1, WFR-2. WFR and their applications in producing fire-retardant wood (WFR wood), fire-retardant plywood (WFR plywood), fire-retardant particleboard (WFR particleboard) and fire-retardant MDF (WFR MDF) were investigated The fire retarders were low toxic, decay resistant and less leachable. The treated wood and WFR panels were of excell...
Zhu Jia Qi, Liu Yan Ji, Gao Chao Ying
Targeted inhibition of wood decay fungi: degradation of cotton cellulose
1999 - IRG/WP 99-10321
Brown-rot decay is responsible for 80% of the damage and replacement of wood in service. For nearly thirty years, researchers have postulated a one-electron oxidase system combining Fe+2 oxalic acid, and H2O2 in the production of hydroxy radicals which ultimately oxidize cellulose in situ. Recently, researchers have been investigating antioxicants, in combination with biocides (Schultz, et al.,199...
F Green III, T A Kuster
Distribution of fire retardant chemicals in kempas (Koompassia malaccensis)
1994 - IRG/WP 94-40037
Samples of Kempas (Koompassia malaccensis) heartwood were treated by vacuumpressure impregnation with solutions of monammonium phosphate, diammonium phosphate, ammonium sulphate or a borax-boric acid mixture. A commercial saltbased fire retardant formulation was also used. After slow air drying, the treated wood samples were sub-divided and zonal analysis carried out in order to determine the grad...
A R A Malek, R J Murphy
Studies of the mechanism of chromated-copper preservative. Fixation using electron spin resonance
1992 - IRG/WP 92-3701
Two softwoods and one hardwood species were treated with chromium trioxide, copper sulphate, chromated-copper wood preservative (CCA). The treated wood samples were analyzed during fixation by electron spin resonance (ESR). ESR spectra indicated that more than one Cr(V) species was generated from Cr(VI) soon after CCA treatment. The Cr(V) signal became strong within increased several hours followe...
K Yamamoto, J N R Ruddick
Fire retardant treated wood and plywood: A comparative study
Part III. Combustion properties of treated wood and plywood
2002 - IRG/WP 02-40236
The fire retardant treated and untreated plywood and alder wood samples were prepared with the aim to investigate the effects of the way of treatment on the combustion properties. Alder wood was used for the preparation of plywood. Boric acid and borax were used as fire retardant. The plywood samples were impregnated by using three different methods; first group samples were impregnated by soaki...
S Çolak, A Temiz, Ü C Yildiz, G Çolakoglu
The lasting dehydration of wood treated by bifluorides worked up in Diffusec noticed by a continual drying of the wood
1999 - IRG/WP 99-30196
After an immersion of sound wood in a solution of Diffusec, in which a combination of acid potassium and ammonium bifluorides = FHF- in dissociated form is present, their potassium and ammonium fluoride ions together with the bifluoride ion = (FHF-) diffuse into the wood. They make use of the woodmoisture available as O-H-O bonds directly attached to the cellulose in the wood fibres to attract the...
H F M Nijman
Environmentally benign wood preservatives based on organic biocide antioxidant combinations: A brief review of laboratory and field exposure results and discussion of a proposed mechanism
2004 - IRG/WP 04-30335
The combination of various organic biocides with commercial antioxidants generally increased the biocides’ efficacy 2-3 fold against wood-destroying fungi in short-term laboratory decay tests, and some positive results have been obtained after 2-4 years of outdoor exposure. The two antioxidants principally examined, propyl gallate and butylated hydroxytoluene, are low cost and, since both are f...
T Schultz, D D Nicholas, W Henry, C Pittman, D Wipf, B Goodell
Metal plate fasteners in trussed rafters treated with preservatives or flame retardants - corrosion risks
1977 - IRG/WP 3104
In designing roof trusses employing metal plate fasteners it is generally assumed that the roof will remain dry in service. Whilst this is generally true, damp conditions do arise under some circumstances, although it is not possible to quantify the extent of the risk. It is only possible, therefore, to give general recommendations which must be interpreted in the light of local experience of serv...
R A Laidlaw, L C Pinion
Uptake of copper by mycelium of wood decay fungi growing on copper S-substituted thioglycolate containing nutrient media
1998 - IRG/WP 98-10291
Mycelia of Trametes versicolor, Coniophora puteana and Poria monticola were grown on potato dextrose agar (PDA) media, containing various concentrations of copper N,N-dimethyldithiocarbamoylacetate (which may be regarded as a copper S-substituted thioglycolate). The tested copper compound revealed relatively low fungicidal activity. After 13-18 day growing period, we determined concentrations of a...
M Humar, M Petric, F Pohleven, P Kalan
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 4: Conversion reactions during storage
1974 - IRG/WP 332
Precipitates simulating those produced in wood by preservative fixation reactions were prepared by the reduction of Boliden K 33 and Celcure AP solutions with hydrogen peroxide and hydrazine. The pH changes on aging at 20 and 50°C were studied and related to the chemistry of fixation previously described. Hydrolysis of copper arsenates may render arsenic acid temporarily water soluble pending pre...
S-E Dahlgren
The bacterial transformation of organic biocides; a common mechanism?
2006 - IRG/WP 06-10585
It was found that a number of unformulated organic biocides showed a susceptibility to degradation by proteobacteria. Exposure of tebuconazole, a candidate biocide, chlorothalonil and IPBC to a Ralstonia strain was found to result in biocide detoxification, as demonstrated through HPLC and a bioassay. Exposure of the biocides to a previously identified extracellular factor was also found to resu...
D F Wallace, D J Dickinson
Arsenic removal by plant pumping mechanism from arsenic solution using activated aluminum oxide as adsorbent – a preliminary study
2006 - IRG/WP 06-50239
This study evaluated the performance of plant pumping mechanism for removal of arsenic from arsenic solution using activated aluminum oxide as adsorbent. Generally, plants absorb water from soil mainly by osmosis process and toxic elements present in soil also move along with water. To remove toxic elements present in contaminated soils/water, different chemical substances are widely used as
...
B Tarakanadha, H Koyanaka, T Hata, Y Imamura
The characteristics of biodegradation mechanism of gamma-irradiated wood
2007 - IRG/WP 07-20352
Gamma radiation, as an easy, fast and effective sterilisation method, changes molecular structure in pest’s living cells, but also in wooden cell walls. Radiation-induced depolymerisation causes significant changes in wood properties crucial for laboratory testing of wood-preservative effectiveness. Natural durability of wood against rot fungi in lab conditions dependency on different sterilisat...
R Despot, M Hasan, F Pohleven, M Humar, G Rep
Fire, flame resistance and thermal properties of oil thermally-treated wood
2007 - IRG/WP 07-40361
Oil thermal treatment, first developed by German scientists, is a promising technology for improving the durability and dimensional stability of wood for outdoor above-ground residential uses such as siding and shingles. The present authors’ previous research showed that 220ºC is an optimal treatment temperature, with 2 hours’ treatment producing wood with significantly improved moisture and ...
Jieying Wang, P Cooper
Surface color and roughness characteristics of medium density fiberboard (MDF) panels treated with fire retardants
2008 - IRG/WP 08-40420
The objective of this study was to determine surface characteristics and color change properties of Medium Density Fiberboard (MDF) treated by fire retardants (FR) with 10% concentration. Experimental panels were made using by melamine ureaformaldehyde (MUF) adhesive having 10%, 15%, 20% of melamine. The surface properties of the samples were determined using a fine stylus technique. Three roughn...
D Ustaömer, M Usta, S Hiziroglu
Antinomic natural self-protection mechanism in long-lasting woods: a case study with three tropical species from French Guiana
2009 - IRG/WP 09-10696
We demonstrate in this work through 3 examples that Amazonian trees may specialize long-lasting woods by means of at least to different approaches. Wallaba impregnates its wood with large amounts of weakly antifungal compounds acting in synergy, while tatajuba and louro vermelho woods are naturally impregnated with antifungal agents. Comparison of biological activities in vitro and concentrations ...
A Rodrigues, M Royer, N Amusant, J Beauchêne, G Herbette, V Eparvier, A Thibaut, L Salmen Espíndola, B Thibaut, D Stien
A theoretical-industrial correlation and perspective on copper-based wood preservatives - a review of thermodynamic and kinetic aspects on copper-wood fixation mechanism
2009 - IRG/WP 09-30499
Copper was and it will continue to remain one of the key active component in wood protection industry. Over the past decades, a significant effort from R&D teams in industry, academia and research institutes was directed toward understanding the copper-wood fixation mechanism, optimising the copper retentions in the wood and reduce leaching in order to maximized performance, prolong the lifetime o...
R Craciun, M Maier, J Habicht
Extensive review of fire-retardant wood composites researches
2009 - IRG/WP 09-40471
The increased demand for public safety has led to greater interest in fire retardant materials in the recently years. Legislation relating to safety in the home, in work locations, on transport facilities and in public places continues to produce new regulation. There is average 524 thousand structure fires occurred every year in US, 3757 civilian in death, about 20 thousand civilian in juries, di...
Zhilin Chen, Zhiyong Cai, Feng Fu
Progress in Fire-Retardant Research on Wood and Wood-Based Composites: a China Perspective
2009 - IRG/WP 09-40476
The fire retardant research on wood and wood-based composites, which was carried out in China in the past two decades, was reviewed with 55 references. While many kinds of fire retardants for wood and wood-based composites have been studied, the mainstream is still the compound or the mixture containing phosphorus, nitrogen and boron elements, which can be used in the form of water solution in th...
Wang Qingwen, Wang Fengqiang, Hu Yunchu, Li Jian
Mould growth on wood-based materials – a comparative study
2010 - IRG/WP 10-20455
Ten different wood-based materials - preservative-treated wood, fire retardant-treated wood, modified wood, WPCs and untreated references of pine sapwood and spruce - were tested for mould growth according to SP method 2899 during 42 days at 90% RH and 22°C.
Even though the results must be interpreted carefully, they indicate significant differences in mould resistance between the materials tes...
P Johansson, J Jermer
The Effects of Some Fire Retardant Chemicals on the Decay Resistance of Medium Density Fiberboard (MDF)
2010 - IRG/WP 10-30536
The objective of this study was to determine the decay resistance of Medium Density Fiberboard (MDF) treated with 5% and 10% concentration of various fire retardant (FR) chemicals. Experimental panels were produced using by melamine-urea-formaldehyde (MUF) resins having 10%, 15% and 20% of melamine content. MDF specimens were subjected to decay resistance test performed according to modified EN 11...
D Ustaömer, M Usta, Ü C Yildiz, S Yildiz, E D Tomak
Effects of intumescent formulation of vinyl acetate-based coating on flame-retardancy of thin painted red lauan (Parashorea spp.) plywood
2011 - IRG/WP 10-40537
Using intumescent coatings on wood-based materials is an effective method for fire safety. The intumescent coatings consist of four major components: (1) binder resin (BR), (2) carbonizing substance (CS), (3) foam producing substance (FPS) and (4) dehydrating agent (DA). Previous studies have demonstrated that the formulation of the four components strongly influences the performance of coatings. ...
Chih-Shen Chuang, Kuang-Chung Tsai, Te-Hsin Yang, Ming-Kuang Wang, Chun-Han Ko