Your search resulted in 115 documents. Displaying 25 entries per page.
Screening of fungal strains for wood extractive degradation
1998 - IRG/WP 98-10254
Fungal strains were screened for their ability to degrade apolar extractives in wood from scots pine. The degradation of total wood extractives by 91 different strains was monitored in stationary batch assays incubated for 6 weeks. The results obtained show that the ability of wood-inhabiting fungi to utilize wood extractives varied greatly, even for different isolates of the same species. Fungal ...
J Dorado, M J Martinez-Inigo, T A van Beek, F W Claassen, J B P A Wijnberg, R Sierra-Alvarez
The effect of certain wood extractives on the growth of marine micro-organisms
1977 - IRG/WP 438
S E J Furtado, E B G Jones, J D Bultman
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
Methodology challenges in developing a transfer of natural durability from sawmill residues, illustrated by experiences with white cypress (Callitris glaucophylla)
2000 - IRG/WP 00-20203
The transfer of durability-conferring extractives from durable to non-durable wood has been accomplished often, but usually as an educational exercise rather than as a commercially oriented process. In the latter environment, many factors previously overlooked become vitally important. How to study them, in the absence of well-developed methodology and given the shorter timeframes being demanded b...
M J Kennedy, M A Powell
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
Estimation of service life of durable timber species by accelerated decay test and fungal cellar test
2002 - IRG/WP 02-20249
Many kinds of durable wood species for outdoor uses has been imported from all over the world to Japan. However information on the natural durability of these species is not sufficient to estimate the service life of them in the climate of Japan. Highly durable species such as Jarrh, Teak, Ipe, Ekki, Selangan batu, Red wood, Western red cedar showed no significant percent mass losses by accelerate...
K Yamamoto, I Momohara
About the relations between the natural durability of some tropical species and their extractives content
1983 - IRG/WP 1208
G R Y Déon
Co-operative research at the Naval Research Laboratory on wood extractives and related compounds as antiborer agents
1977 - IRG/WP 429
J D Bultman, K K Parrish
Autoxidation of beech condensate
2003 - IRG/WP 03-40261
Liquid effluent from steaming beech wood was studied. The effluent contains many phenolic compounds which can present a significant toxicity. The effluent was treated by oxidation was carried out at 250 rpm for 30 min with NaOH. This was followed flocculation with CaCl2 for 30 min. The influence of parameters such as pH, time of autoxidation were studied. Experimental results reveal the electrosta...
M Irmouli, J P Haluk
Decay resistance of Scots pine (Pinus sylvestris) heartwood against brown rot
2002 - IRG/WP 02-10433
Natural decay resistance of wood is mainly restricted in the heartwood and based on wood microstructure and chemical composition. The genetic variation in the durability of Scots pine (Pinus sylvestris L.) wood against decay and the relationship between resistance and chemical composition was studied. The laboratory tests of 6 and 8 weeks were carried out with a brown rot fungus Coniophora puteana...
H Viitanen, A M Harju, P Kainulainen, M Venäläinen
Effect of permeability and extractives on the decay rate of southern pine sapwood in above grund exposure
2005 - IRG/WP 05-20310
The effects of wood permeability and hydrophilic and hydrophobic extractives on the decay rate of southern pine sapwood in above ground exposure were investigated. Permeability was determined by water sorption measurements, and the effect of extractives was studied by pre-extracting the test samples prior to outdoor exposure using water to extract hydrophilic extractives or sequential methanol/cy...
D D Nicholas, T Schultz, L Sites, D Buckner
The chemical analysis and biological evaluation of wood extractives as potential timber preservatives
1995 - IRG/WP 95-30090
Work involved the biological performance of water and organic solvent soluble extractives of four naturally durable wood species, namely; Matumi, Tamboti, Sneezewood and the Turpentine tree. These timber species are known to be naturally durable against termites and fungi (±25 to 35 years). The extractives were evaluated against termites and fungi using impregnated pine pencil stakes in field tes...
P Turner, D Conradie
Relationship between bond strength and surface characteristics of CCA-treated Douglas-fir
1993 - IRG/WP 93-30008
Chromated-copper-arsenate (CCA) treated Douglas-fir was laminated using a commercial phenol-resorcinol resin. CCA treatment enhanced the water repelleney of wood espeeially in the presence of extractives. However, the shear strength of CCA treated wood was 12% lower in dry condition and 38% lower in wet condition after six cycles of vacuum-pressure test than that of untreated wood. Slight removal ...
K Yamamoto, J N R Ruddick
UV-microspectrophotometry of lignin and accessory compounds in wood cell walls of conifers
1999 - IRG/WP 99-20171
The distribution of lignin in the cell wall of conifer tracheids was determined by UV-VIS microspectro-photometer. Wood sections of one micron thickness were measured between the wavelength 240 and 700 nm. Spectral analyses revealed that the conifer lignin associated with the tracheid secondary wall and middle lamella is composed of guiacylpropane units which exhibit a characteristic UV absorption...
G Kleist, G Koch, J Bauch
Bioassays of extracts from scaly ash (Ganophyllum falcatum B1) against the subterranean termite Coptotermes acinaciformis (Froggatt)
1983 - IRG/WP 1206
Scaly ash, Ganophyllum falcatum B1. wood shavings were extracted by methanol, and fractionated with ethyl acetate, diethyl ether and water, and the anti-termitic properties of these materials bioassayed against the subterranean termite Coptotermes acinaciformis (Froggatt). Laboratory techniques were developed to overcome the problem of limited extractive materials. The results of the various bioas...
J R J French, J P Robinson, J W Creffield
Wood extractives as carbon sources for staining fungi in the sapwood of lodgepole pine and trembling aspen
1995 - IRG/WP 95-10098
Wood discoloration by sapstaining fungi reduces lumber value. In Canada, the most commonly recorded sapstaining fungi belong to the genera Ophiostoma. This work evaluated the effect that Ophiostoma piceae, Ophiostoma ainoae, and Ophiostoma piliferum used the lipids present in the sapwood of lodgepole pine (Pinus contorta Dougl.) and trembling aspen (Populus tremuloides Michx.). Wood lipids, common...
Yong Gao, C Breuil
The influence of the natural extractives of opepe (Nauclea diderrichii) and African padauk (Pterocarpus soyauxii) timbers on their durability
1996 - IRG/WP 96-30098
Many timbers contain chemical extractives that undoubtedly play a key role in the timber's natural durability. Opepe (Nauclea diderrichii) and padauk (Pterocarpus sp.) are both very durable timbers (class 1), yet they are described as being moderately permeable. This suggests the presence of biocidal chemicals within these timbers, rather than simple blocking agents. Initial trials on the...
E D Suttie, R J Orsler
Natural Durability of Tropical Species – Variations and Prospects
2005 - IRG/WP 05-10568
The tropical timber resources of the world play an unequivocal role in economic development of both the tropical timber producing and importing regions. This paper describes natural durability as an important and preferred wood quality of tropical species of the world with emphasis on Malaysian hardwoods, the link between various aspects of tropical hardwood durability, hardwood utilization and bi...
A H H Wong, Yoon Soo Kim, A P Singh, Wang Choon Ling
Effect of angle of exposure on degradation of radiata pine during weathering trials
1988 - IRG/WP 2301
The importance of angle of exposure on the degree of weathering of materials has not been adequately resolved. In conventional tests, specimens are exposed at an angle of 45° facing the equator, but more recently experiments on polymeric materials have suggested that an angle of 0° may be preferable since this angle maximises levels of received ultra-violet radiation. In this paper the degradati...
P D Evans
Termite resistance of Malaysian and exotic woods with plantation potential: Laboratory evaluation
1998 - IRG/WP 98-10280
The resistance of selected Malaysian woods to attack by the representative aggressive subterranean termite Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) was evaluated in four-week, no-choice laboratory tests. This is part of an ongoing effort between the Forest Research Institute Malaysia and the University of Hawaii to document the termite resistance of Malaysian timber species of po...
J K Grace, A A H Wong, C H M Tome
Effects of alkali treatment on some mechanical and chemical properties of creosote treated oaks
1991 - IRG/WP 2366
To date, there is a lack of information on the effects of chemical treatment on the performance of creosote preservative treated oak sleepers. This factorial experiment was designed to analyze three main effects: species (Quercus alba and Quercus rubra) creosote treatment (treated and untreated), and alkali (NaOH) soaking (0, 1, and 10 percent). The modulus of elasticity (MOE) and fiber stress at ...
P Chow, A J Reinschmidt, E J Barenberg, L C Chang
Biocidal screening method of wood extractives by a direct use of cellulose TLC plate
2001 - IRG/WP 01-20226
Most of the methods to evaluate the biological durability of woods have focused on decay fungi and termite as deteriorating organisms and it is well known that one of the most important factors affecting the biological characteristics of wood is extractives. Bioassays for evaluating the biological activities of wood extractives have been mainly conducted with treated filter papers for termites or ...
R Yusiasih, T Yoshimura, T Umezawa, Y Imamura
Durability of five wood species against Coriolus versicolor
1992 - IRG/WP 92-1578
The durability of following five wood species Zelkova carpinifolia, Ulmus glabra, Carpinus betulus, Acer trauvetteri and Pterocarya fraxinifolia were studied against Coriolus versicolor under laboratory conditions according to DIN 52176 standards. Zelkova caprinifolia shows a reduction in weight of 2.19%, Ulmus glabra 41.69%, Carpinus betulus 45.64%, Acer trauvetteri 53.05%, and Pterocarya fraxini...
S M Kazemi
The antifungal efficacy of Guayule resin
1987 - IRG/WP 3429
The Naval Research Laboratory is evaluating the non-rubber-producing portion of guayule (Parthenium argentatum) resin as a protectant for wood in terrestrial and marine service. This study phase, in collaboration with the universities of Arizona and Mississippi State, evaluates the resin's fungicidal worth. Resin-impregnated pine sapwood was exposed to brown rot fungi (Gloeophyllum trabeu...
J D Bultman, R L Gilbertson, T L Amburgey, J E Adaskaveg, S V Parikh, C A Bailey
Relationship of wood durability and extractives
2003 - IRG/WP 03-10493
The durability of the following five wood species, Zelkova carpinifolia, Ulmus glabra, Pterocarya fraxinifolia, Carpinius betulus and Acer laetum, were studied. Wood blocks were exposed to Coriolus versicolor under laboratory conditions according to DIN 52176 standard. After 16 weeks incubation the heart wood of Z carpinifolia showed 2,19 % weight loss, U glabra 41,69 %, C betulus 45,64 %, A laetu...
S M Kazemi