Your search resulted in 127 documents. Displaying 25 entries per page.
Enzyme systems of bacterial isolates from ponded logs - Potentials of pectin and/or starch degradation
2000 - IRG/WP 00-10378
This paper deals with the degradation potentials of wood constituents by the bacterial isolates from ponded logs. The potentials to degrade pectin as a constituent of pit-tori as well as starch existing in ray parenchyma cells in the areas of sap- and transition wood with the isolates were examined. The pectinase activity was investigated by means of the degradation degree of a carrot strip used a...
S Doi, S Ohta
A new method for the study of microbiological decay of wood in a strictly anaerobic environment
1988 - IRG/WP 2319
Recent work has suggested that strictly anaerobic bacteria may play a role in the biodeterioration of wood, particularly in aqueous environments. However, no suitable test methods exist for the investigation of this hypothesis. An aqueous minimal medium in specifically adapted conical flasks was sterilised, gassed using a 5.5% H2; 31.8% C02; 62.7% N2 gas mixture to remove oxygen and transferred to...
G M Rogers, A A W Baecker
Treatment of lumber with preservative/water repellent emulsions - The significance of shear stability on penetration
1997 - IRG/WP 97-20124
Currently, the treatment of lumber with a water repellent emulsion and a wood preservative formulation in combination is the most cost effective way to prevent decay and to maintain the appearance of uncoated lumber in service. Water repellents influence the movement of moisture into and out of wood and, by so doing, can decrease checking and splitting significantly. Adequate penetration of the em...
F Cui, K J Archer
Biological resistance of aldehyde-treated wood
1994 - IRG/WP 94-40018
Biological resistance of wood treated with aldehyde cross-linking agents such as glyoxal, glutaraldehyde and dimethylol dihydroxy ethyleneurea (DMDHEU) were investigated. Sapwood blocks of Japanese cedar and Japanese beech, measuring 20 x 20 x 10 mm³ (T x R x L), were vacuum-impregnated at room temperature with 5-25% of aldehyde solutions. Blocks were kept in the solution for 1 week to gain the o...
S Yusuf, Y Imamura, M Takahashi, K Minato
Preliminary studies of the decay mechanism of some brown-rot fungi
1989 - IRG/WP 1402
The importance of the enzymatic degradation of hemicellulose and cellulose by brown-rot fungi is still under discussion. Endo-ß-1,4-xylanase and endoglucanase activities of Coniophora puteana and Poria placenta cultures were measured by the increase in reducing groups. Enzymes were produced in liquid and solid sawdust based culture media. Enzyme activities were measured in two, four and eight wee...
A-C Ritschkoff, H Viitanen
Influencia de la impregnación con soluciones tánicas en la estabilidad dimensional de la madera de Pinus pinaster Ait. procedente de España
1992 - IRG/WP 92-3686
En virtud de la importancia que presenta la madera de Pinus pinaster Ait. en el sector constructivo español, se ha sometido a esta a tratamientos en autoclave con distintas soluciones tánicas naturales y artificiales a fin de estudiar su incidencia en la estabilidad dimensional frente a exposiciones exteriores. En el estudio se pone de manifiesto el efecto creado por el tratamiento protector en ...
J A Rodríguez Barreal, J Cubillo Jordan de Urries, L Garcia Esteban
Thermal modification of non-durable wood species 1. The PLATO technology: thermal modification of wood
1998 - IRG/WP 98-40123
The PLATO technology is an innovative upgrading technology with low environmental impact, which can be applied to fast grown and non-durable wood species. This technology is based on a thermal modification of solid wood without the addition of chemicals (e.g. preservatives), consisting of a hydrothermal treatment, followed by drying and curing. The PLATO technology results in a substantial improve...
M J Boonstra, B F Tjeerdsma, H A C Groeneveld
Improvements of stability and durability of beechwood (Fagus sylvatica) by means of treatment with acetic anhydride
1991 - IRG/WP 3645
In the present investigations, beechwood (Fagus sylvatica) was treated with non-catalysed acetic anhydrid at 120°C and some physical- and biological parameters of the treated wood were compared with those of non-treated wood. The radial and tangential shrinkage and swelling, respectively, and the absorption capacity of the acetylated wood against moisture is considerably lower. The durability aga...
H Militz
Influence of concentration, catalyst, and temperature on dimensional stability of DMDHEU modified scots pine
1998 - IRG/WP 98-40119
Dimethyloldihydroxyethyleneurea (DMDHEU) is being used in textile industry to improve wrinkle recovery. Trials on solid wood have been performed to minimise swelling of the wood. This paper focuses on the effect of various types and concentrations of catalyst and reaction temperature on the dimensional stability of Scots pine. Three different catalysts, NKS (based on magnesium chloride), 3282 (bas...
M Van der Zee, E P J Beckers, H Militz
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
Soil bed studies of the dimensional stability of composite products
1999 - IRG/WP 99-40134
The influence of boron and isocyanate resin on the dimensional stability of high moisture resistant particleboard was assessed after burial in a soil bed for one month. The samples were treated with two levels of a boron compound and coated in isocyanate resin. The samples were randomly placed in a fungal cellar in soils of two different water holding capacities. Weight differences and dimensional...
K M Filcock, P Vinden
Effect of alkaline phenolic resin adhesive on the stability of preservatives incorporated into the glue-line of plywood
1991 - IRG/WP 3650
Stability of preservatives was determined by gaschromatographic analysis when they were applied to glue-line treatment of plywoods. Among organophosphorous insecticides, emulsified forms of chlorpyrifos, dichlofention and diazinon were more stable than others. Fenitrothion, pyridafenthion and phoxim were not practically acceptable as emulsifieable forms due to the relatively low recovery rates aft...
S Fushiki, Y Katuzawa
Copper linoleate: A new low toxcity wide spectrum, heavy duty wood preservative
1995 - IRG/WP 95-30082
Copper linoleate, a "fixed" copper soap has been developed and evaluated in South Africa over a 30-year period. The initial product, an organic solvent based preservative has been tested in pine poles against termites and fungi. Results indiate that the product has performed well against existing heavy duty wood preservatives such as CCA and creosote in long term field trials (30 years). The paper...
D Conradie, P Turner, W E Conradie, A J Pendlebury, T Pizzi
Effect of boron compounds-furfuryl alcohol treatment of wood on dimensional stability, termite resistance and boron leachability
2001 - IRG/WP 01-40195
Sapwood blocks of Japanese cedar (Cryptomeria japonica) and Caribbean pitch pine (Pinus caribaea) measuring 20 (tangential) x 20 (radial) x 10 (longitudinal) mm were impregnated with furfuryl alcohol (FFA) by a vacuum-diffusion process followed by curing under heating. Boron compounds (boric acid, ammonium borate and ammonium biborate) were mixed in the impregnation solution of FFA. Anti- swelling...
S K Ozaki, M K Yalinkilic, Y Imamura, M F Souza
Studies on the resistance of DMDHEU treated wood against white-rot and brown-rot fungi
2005 - IRG/WP 05-10566
Beech wood (Fagus sylvatica) modified with the textile finishing agent 1,3 dimethylol-4,5-dihydroxyethylen urea (DMDHEU) has shown to improve durability against the white-rot fungus Trametes versicolor. In a mini-block test, the weight loss over eight weeks of incubation decreased with increasing weight percent gain (WPG) of DMDHEU. At 25% WPG, no significant weight loss was observed, while untrea...
P Verma, C Mai, A Krause, H Militz
Development of wood retification process at the industrial stage
1998 - IRG/WP 98-50101-16
Wood is a natural composite material which exhibits outstanding properties from the technical as well as from the ecological point of view. However, it is an anisotropic, hygroscopic material sensitive to biological attacks. We have to stabilise and preserve it if we want to ensure its market shares faced with competing synthetic material, whilst taking the new environmental rules into account.
T...
P Gohar, R Guyonnet
The effect of Trichoderma volatiles on the growth and enzyme production of Serpula lacrymans
2000 - IRG/WP 00-10332
Although various authors have reported the biological control of Serpula lacrymans by Trichoderma spp. the mode of antagonism employed by Trichoderma is not yet clear. The work presented here concentrates on the production of anti-fungal volatiles for inhibition of S. lacrymans growth. Volatile mediated interactions were examined between four S. lacrymans isolates and a range of nine known Trichod...
S N Humphris, A Bruce, R E Wheatley
Micromorphology of Schizophyllum commune attack in pine (Pinus sylvestris) wood
1983 - IRG/WP 1184
The decay pattern caused by Schizophyllum commune in pine latewood tracheids was studied using both light and transmission electron microscopy. The attack began as isolated concentric slits within the S2 layer with extensive lamellation and separation of individual wall layers observed in subsequent stages of decay. The slits resulting from attack appeared to be formed in thin, regular concentric ...
T Nilsson, G F Daniel
Influence of different resin treatments on the dimension stability of wood
1997 - IRG/WP 97-40090
The dimension stability of wood is considered to be an important contribution to its durability and its performance in practice. A number of different treatments have been developed to improve the dimension stability of wood. One applied method is the treatment of wood with monomers or resins. The application of appropriate impregnation conditions seemed to be essential to enhance the efficiency o...
M Sailer, A O Rapp
The Protection of Wood with Oxy-aluminium Compounds
2002 - IRG/WP 02-30286
Wood inorganic composites (WICs) containing aluminium compounds were developed and tested in relation to some essential requirements of preservative treated wood. Four different oxy-aluminium treatments were developed and identified according to the final insoluble compounds formed (sodium aluminate, aluminium hydroxide, magnesium aluminate and aluminium borate) in wood. Vacuum impregnation or dou...
F A Ximenes, P D Evans
Tebuconazole - A new triazole fungicide for wood preservation
1990 - IRG/WP 3629
The main cause of economic damage to timber and millwork worldwide are Basidiomycetes (brown and white rot). After testing a wide range of triazole derivatives for their effectiveness against decay fungi, Tebuconazole, a triazole compound, was selected. The physico-chemical, toxicological and ecotoxicological data of this substance are described. Tebuconazole is unleachable, light-stable, heat-sta...
R Gründlinger, O Exner
Thermal modification of non-durable wood species 2. Improved wood properties of thermal treated wood
1998 - IRG/WP 98-40124
Properties of wood treated in a new heat-treatment process called the PLATO-process have been studied. Several wood species have been treated using this new thermal modification process using a range of process conditions (mainly time and temperature). In this study the characteristics of the treated wood were determined using samples from whole planks treated on pilot plant scale. The modified ch...
B F Tjeerdsma, M J Boonstra, H Militz
The use of natural and synthetical tannins to improve the dimensional stability and durability of beechwood (Fagus sylvatica)
1993 - IRG/WP 93-30016
Synthetical tannins and natural extractives of oak, spruce and chestnut have been combined with different fungicides to make the wood more dimensionally stable and more durable. The anti-shrink-efficiency and the improvement of the durability of different synthetical and natural tannins have been evaluated. The results make clear, that an application of the mentioned agents for common use cannot b...
H Militz, W J Homan
Dimensional stability and decay resistance of wood upon modification with some new type chemical reactants
1994 - IRG/WP 94-40028
Solid wood of home grown species can be upgraded by chemical modification with environmentally acceptable chemicals. The best kwown example of modification reaction is acetylation with acetic anhydride. A continued search for reactive chemicals other than acetic anhydride is ongoing, aiming at the improvement of technical properties of wood. This contribution deals with the results of a screening ...
P Goethals, M Stevens
Improvement in dimensional stability against water of the main Spanish timbers impregnated with water repellent organic protectors
1988 - IRG/WP 3468
The study reported the increase of dimensional stability against water of the main Spanish timbers, both broadleaved and coniferous, after impregnation in the autoclave with organic protector, with contains 33.3% water repellent waxes and resins. The proposed Spanish standard, U.N.E. n° 56541 is used, where dimensional stability of the impregnated wood is expressed as a% of that of the non-impreg...
J A Rodríguez Barreal