Your search resulted in 69 documents. Displaying 25 entries per page.
Test Methods – Performance Based Requirements
2004 - IRG/WP 04-20297
In this paper is briefly described the present approach to service life prediction as an essential part of the architectural engineering process. The system of testing the durability of wood is described more in detail including laboratory tests as well as field trials. It is concluded that the system has a lot of weaknesses which makes it less well suited for practical building applications. A le...
M-L Edlund, F Englund, J Jermer, T Nilsson, M Westin, K Ödeen
Decay types observed in small stakes of pine and Alstonia scholaris inserted in different types of unsterile soil
1990 - IRG/WP 1443
The attack of various wood-degrading microorganisms occurring in mini-stakes of pine and Alstonia scholaris buried in various types of unsterile soil was studied. Attacks by white rot, brown rot, soft rot, erosion bacteria, tunnelling bacteria and actinomycetes were found. Soft rot occurred in all soils, whereas attack by white rot and especially brown rot and erosion bacteria was rare. The type o...
T Nilsson, G F Daniel
Leachability And Decay Resistance of Copper-Treated Wood
2004 - IRG/WP 04-30337
Samples of scots pine sapwood (Pinus sylvestris L.) were treated with solutions of (Copper II sulfat-5 hydro + fluoroboric acid) and (Copper II sulfat-5 hydro + fluoroboric acid + boric acid) in order to determining to leachability and decay resistance against brown rot fungus (Postia placenta) and white rot fungus (Coriolus versicolor).
Results indicated that the copper in treated wood is less s...
A Temiz, T Nilsson, I Deemirtas, Ü C Yildiz
The possible significance of the lignin content and lignin type on the performance of CCA-treated timber in ground contact
1988 - IRG/WP 1357
The lignin in wood samples of Alstonia scholaris, Octomeles sumatrana and a Simaruba species have been analysed. These timbers are characterised by a high lignin content and low syringyl:guaiacyl ratios. Decay tests with two soft rot fungi showed that the timbers were less susceptible than timbers with a low lignin content and higher syringyl:guaiacyl ratios. Numerous data for field performance of...
T Nilsson, J R Obst, G F Daniel
Fungus cellar and field tests with tall oil derivatives. Final report after 11 years' testing
1993 - IRG/WP 93-30007
Two derivatives of tall oil were tested as wood preservatives in a fungus cellar and in ground contact (field test). Stakes of Pinus sylvestris sapwood were used in the tests. For the field test the size of the stakes was 20 x 50 x 500 mm³ and for the fungus cellar test 20 x 20 x 250 mm³. The stakes were vacuum-pressure treated with the two products and exposed in 1981. The field test site used ...
J Jermer, Ö Bergman, T Nilsson
Worldwide in-ground stake test of acetylated composite boards
1997 - IRG/WP 97-40088
Acetylated wood composite stakes are being tested in ground contact (graveyard test) in seven fields around the world. Three types of acetylated wood composites were prepared: spruce fiberboard in Sweden, aspen fiberboard in Madison and rubber wood particle board in Indonesia. Two levels of acetylation were used, a high level of ~20% acetyl content and a low level of 10% acetyl content. Control bo...
R M Rowell, B S Dawson, Y S Hadi, D D Nicholas, T Nilsson, D V Plackett, R Simonson, M Westin
Formation of soft rot cavities in relation to concentric layers in wood fibre walls
1983 - IRG/WP 1185
A large number of timber species attacked by soft rot have been examined using light microscopy. The S2 layers in a large number of the timbers exhibited special structural features in the form of thin concentric layers. Several observations indicate that these layers may be characterised as "weak" zones by being more easily degradable than the surrounding wall layers. The chemical structure of th...
T Nilsson, G F Daniel
The implementation of restrictions on the use of arsenic and chromium based wood preservatives in Sweden
1995 - IRG/WP 95-50062
In 1992 the Swedish National Chemicals Inspectorate introduced restrictions on the use of wood treated with arsenic and/or chromium based wood preservatives. Such wood is now in principle only allowed for use in ground contact or in water. These restrictions have had considerable influence on the use of wood preservatives for sawn timber for the Swedish domestic market. Thus only 35% of the preser...
J Jermer, M-L Edlund, K Nilsson
Microbial decay of an archaeological wood
1994 - IRG/WP 94-10053
A light and transmission electron microscopic investigation of an archaeological wood was undertaken to determine the cause of its deterioration. The wood came from a bulwark constructed in early 1100 in the lake Tingstäde Träsk on the island Gotland in Sweden. The samples of the wood, which was identified as Pinus sylvestris, were taken from a depth of 0.85 m below the bottom level. The wood wa...
A P Singh, T Nilsson, G F Daniel
Natural durability of 4 different Larix species tested in soil contact
2002 - IRG/WP 02-10434
Importers of Siberian Larch claimed to have a material which can replace pressure treated wood in soil contact. This gave reason to investigate the durability of 4 different Larix species (L. decidua, L. sibirica, L. decidua x sibirica, L. gmelini var ologenis) coming from 7 different origins in comparison with sapwood of Pinus sylvestris untreated as well as pressure impregnated with retentions o...
A O Rapp, H Viitanen, T Nilsson
The Efficacy of Wood Preservative Treatments in Laboratory Soil-Bed Test
2004 - IRG/WP 04-20289
The efficacy of wood preservatives were determined in laboratory soil-bed test. Pine and alder wood samples (10 x 10 x 10 mm) were treated with CCA (1, 2%), ACQ-1900 (2, 3%), ACQ-2200 (1, 2%), Tanalith E 3491 (2, 2,8%), Wolmanit CX-8 (1, 2%). The leached and unleached samples were exposed 76 days at Simlångsdalen soil and determined mass loss.
The results of this study showed that mass losses o...
A Temiz, T Nilsson, Ü C Yildiz, E D Gezer, S Yildiz
On the occurrence of Phialophora species in preservative treated wood in ground contact
1977 - IRG/WP 163
Phialophora is a fairly large genus comprising about thirty described species. They are widespread in very diverse environments, such as soil, sea water, wood and wood pulps. Some species are known as parasites on plants and animals, including man. Phialophora species were early known for their ability to produce blue stain in timber. Later it was discovered that several species were able to produ...
T Nilsson, B Henningsson
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
Attempts to isolate tunnelling bacteria through physical separation from other bacteria by the use of cellophane
1992 - IRG/WP 92-1535
During attempts to isolate tunnelling bacteria in pure culture, physical separation from other bacteria was successfully achieved by the use of cellophane. Cellophane was used in liquid cultures as a substrate for tunnelling bacteria that were present in a mixture with other bacteria. By tunnelling into cellophane, TB were physically removed from contaminating bacteria which could then be removed ...
T Nilsson, G F Daniel
Cytoplasmic and extracellular localization of manganese II dependent peroxidase(s) in white rot fungi during degradation of woody materials
1989 - IRG/WP 1416
The manner by which lignin is degraded in-situ in natural substrates by white rot fungi still remains a controversial issue particularly the distribution and role(s) played by lignin degrading enzymes (i.e. manganese II peroxidase and lignin peroxidase). In the present study, use was made of anti-manganese II peroxidase and immunolabelling techniques in conjunction with transmission electron micro...
G F Daniel, B Pettersson, T Nilsson, J Volc
Tunnelling bacteria
1983 - IRG/WP 1186
The micromorphology of decay in wood caused by a certain group of single-cell bacteria, called tunnelling bacteria (TB), is described. TB are characterised by their tunnelling ability within the secondary cell walls of wood fibres. Pure cultures of TB have not yet been obtained although the typical decay patterns can be reproduced using mixed bacterial cultures. Some indications of lignin degradin...
T Nilsson, G F Daniel
Field Trials with mini-stakes
2002 - IRG/WP 02-20244
In 1995 an extensive field test program with wood mini-stakes, 8 x 20 x 200 mm, was started. In these trials a large number of parameters are being evaluated, including several new wood preservatives, differently chemically modified woods and natural durability of various wood species. The test sites are three fields in Sweden for in-ground and “close to ground” testing, one subterranean termi...
M Westin, A O Rapp, Y S Hadi, T Nilsson
Estimation of mycelial biomass by determination of the ergosterol content of wood decayed by Coniophora puteana and Fomes fomentarius
1989 - IRG/WP 1415
The mycelial biomass of fungi decomposing wood materials may be estimated by the use of an ergosterol assay technique.ln decay tests, essentially according to EN 113, estimates made by HPLC analyses on wood decayed by Coniophora puteana and Fomes fomentarius show the increase in biomass in the wood blocks. The ergosterol contents were correlated with dry weight loss determinations. Degradation of ...
K Nilsson, J Bjurman
Influence of variable lignin content amongst hardwoods on soft-rot susceptibility and performance of CCA preservative
1982 - IRG/WP 1151
This paper presents the outline of an argument, based on both new and established data, which relates varying lignin content to variation of soft-rot susceptibility between hardwood species and of performance of CCA preservatives in controlling soft-rot. Although more data need to be generated to prove this relationship, sufficient evidence exists for the hypothesis to be given close attention, pa...
J A Butcher, T Nilsson
Natural durability of larch heartwood against decay
1997 - IRG/WP 97-10201
Larch heartwood has been promoted in Sweden and in other European countries as an alternative to preservative treated timber. It has even beeen stated that larch heartwood is more durable than preservative treated timber. This paper presents a compilation of facts from scientific reports on the durability of larch heartwood. Some recent data from this department are also reported. All data suggest...
T Nilsson
New ways of chemical wood preservation
1997 - IRG/WP 97-40087
Synergistic effects pertaining to wood preservation have been investigated by combining different polymerizing agents with modifying chemicals, modifying chemicals with known preservatives and new types of preservative chemicals with each other. One of the investigated methods is the use of impregnating solutions based on furfuryl alcohol (produced from biomass), in which the chemicals polymerizes...
M Westin, T Nilsson, B Ohlsson, R Simonson
Ultrastructure of Prumnopitys ferruginea wood from a buried forest in New Zealand
1991 - IRG/WP 1489
The buried wood of Prumnopitys ferruginea, a New Zealand native tree, was examined by scanning and transmission electron microscopy to investigate the extent to which the wood had deteriorated and the cause of its deterioration. Examinations showed that some deterioration of wood had occurred. Microscopy revealed a decay pattern similar to that produced by cavitation bacteria. Lenticular cavities ...
A P Singh, T Nilsson, G F Daniel
Evidence for actinomycete degradation of wood cell walls
1990 - IRG/WP 1444
Several unique patterns of degradation occurring in wood cell walls have been observed in wooden stakes inserted in unsterile soil in the laboratory. Some of the patterns have also been observed in coniferous wood taken from forest floors. All the observed attack types occur within wood cell walls, mainly within the S2 layer. Attack is characterised by channels of varying diameter or small fusifor...
T Nilsson, G F Daniel, S L Bardage
Fouling assemblage development on copper-chromium-arsenic-treated timber submerged in European waters
2002 - IRG/WP 02-50181
The effect of the anti-marine-borer timber preservative CCA on community development of non-target marine fouling animals was investigated. Panels of Scots pine treated to target retentions of 12, 24 and 48 kg CCA per m3 of wood, plus untreated controls were submerged at seven coastal sites (Portsmouth, UK; La Tremblade (2 sites), France; Ria Formosa, Portugal; Sagres, Portugal; Kristineberg, Swed...
C Brown, R J Eaton, S M Cragg, P Goulletquer, A Nicolaidou, M J Bebianno, J Icely, G F Daniel, T Nilsson, A J Pitman, G Sawyer
Ingestion of wood-degrading micro-organisms
1991 - IRG/WP 4169
An ultrastructural study was carried out on the digestive tract contents of Limnoria lignorum, frass, gallery walls and surface structures of the animals. The purpose of the study was to determine whether wood-degrading bacteria, fungi and other microbes and/or wood degraded by these microbes were present in gut regions and therefore could provide indirectly a nutritional source for Limnoria. Both...
G F Daniel, S M Cragg, T Nilsson