Your search resulted in 655 documents. Displaying 25 entries per page.
Influence of variable lignin content on brown rot decay of wood
1987 - IRG/WP 1320
Compilation of published data and new experiments with brown-rotting fungi on different timber species suggest that their decay activity, in contrast to soft rot and white rot fungi, is not greatly influenced by the type or amount of lignin present....
T Nilsson, G F Daniel
The Effect of Heat on the Retention of Ammoniacal Copper Quat (ACQ-AB) onto Scots Pine (Pinus Sylvestris L.) Wood
2008 - IRG/WP 08-40390
In this study, the sapwood of Scots pine (Pinus sylvestris L.) were treated with ammonical copper quat type (ACQ-AB), which is one of the environmentally friendly wood preservatives, by using soaking method as a functions of various temperatures and time. The results indicated that the retention behaviour of ACQ onto the wood was considerably affected by temperature of ACQ solution and treatment t...
M Hakki Alma, A Mukremin Kara
Aspergillus fumigatus Fresenius resistance to chemical preservatives in piles of pine and birch wood chips
1981 - IRG/WP 1146
Investigation has been carried out on the communities of fungi developing in birch and Scots Pine chip piles in the Ostroleka Pulp and Paper Mill in the North-East of Poland The species composition or fungal communities and their development in a dozen of chip piles during storage was investigated. Untreated and chemically treated birch and pine wood chips were investigated. In all samples the gre...
M H Zielinski
Acetylation of lignocellulosic materials
1989 - IRG/WP 3516
A simplified procedure for the acetylation of lignocellulosic materials has been developed. The acetylation is done with a limited amount of liquid acetic anhydride without the addition of a catalyst or an organic co-solvent. Dimensional stability and biological resistance are both much improved by the acetylation. Equilibrium moisture content in acetylated material is considerably lower than in u...
P Larsson, A-M Tillman
Artificial drying of impregnated wood
1987 - IRG/WP 3448
Sawn timber (Pinus Sylvestris) of dimension 50x150 mm was impregnated with CCA by a full-cell process. The timber was then dried in a conventional kiln or a special vacuum kiln where the timber was dried by circulating superheated steam. Drying time was 16 days and 2 days respectively. The aim of the investigation was to compare the physical appearence of the wood after drying by the two methods w...
M-L Edlund
The yeast Pichia sp. As a short-term biological control agent to fungal spoilage of sawn softwood timber
2000 - IRG/WP 00-10362
Previous work has found isolates of the yeast Pichia to be a successful biological control agent toward moulding of fruits. An isolate was tested for the ability to protect sapwood of Pinus sylvestris timber against visual degrade by surface growth of moulds and staining fungi. Successful protection of autoclaved wood sprayed with a mixture of common wood moulding fungi was achieved when the yeast...
C Payne, H J Staines, A Bruce
Testing method for the treatability of wood
1994 - IRG/WP 94-40031
In order to test and classify the treatability of wood species in pressure treatment processes with water-based solutions, a laboratory method was developed which allows the testing of small samples and limited sections of a stem, e.g. sapwood. The penetration of different liquids was determined separately concerning the three anatomical directions of wood. The common parameters for pressure impre...
A O Rapp, R-D Peek
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
Chromium on the surface of CCA-treated wood
1978 - IRG/WP 386
Chromium in solutions of CCA preservatives is predominantly in the hexavalent state (Cr VI). It is well known that Cr VI is associated with dermatitis and skin ulceration in workers handling chromium containing products and processes. When reduced to the trivalent state, however, chromium is considerably safer. An essential part, therefore, of safety procedures in any chromium - using industry is ...
C R Coggins, P Hiscocks
Retention and distribution of copper/chrome/arsenic (CCA) in pressurised sap-displaced UK grown spruce and pine
1986 - IRG/WP 3366
Increment cores were taken from UK grown Scots pine (Pinus sylvestris L.), Corsican pine (Pinus nigra var. maritima Ait), Sitka Spruce (Picea sitchensis (Bong) Carr), and Norway spruce (Picea abies (L) Karst) distribution poles treated by pressurised sap-displacement using a 1.8% copper, chrome, arsenic (CCA) solution. Each increment core was sectioned radially and the copper, chrome, and arsenic ...
P D Evans, G M Smith, B King
The volatilization of arsenic on burning copper-chrome-arsenic (CCA) treated wood
1978 - IRG/WP 3111
Small scale burning experiments are described involving copper-chrome-arsenic treated wood. Approximately 20 per cent of the arsenic was volatilised when the wood was burned in air but 60 per cent when burned in an oxygen-enriched atmosphere, this increase is attributed to an increase in combustion temperature. Although a small increase in arsenic evolution was found with an increased concentratio...
A-J Dobbs, C Grant
A potential anti-sapstain chemical for sawmills
1984 - IRG/WP 3300
Several biocidal formulations were tested under laboratory conditions in order to discover an alternative antisapstain chemical to chlorophenoxides. The formulations tested were experimental water solutions containing a quaternary ammonium chloride, a commercial fungicide and/or a sodium salt of some carboxylic acids. The effect of sodium carbonate and borax decahydrate in mixture with a quaternar...
I A Linderborg
Initial microbial colonisation of CCA-treated, creosote-treated and untreated Pinus sylvestris L. blocks in seawater
1996 - IRG/WP 96-10171
CCA-treated, creosote-treated and untreated Pinus sylvestris sample blocks were immersed in a seawater through-flow system for periods of between 1 and 265 hours. Samples were fixed immediately on removal and examined both qualitatively and quantitatively using the scanning electron microscope. This study of primary microbial colonisation showed differences between treatments in the diversity of m...
K Sturgess, A J Pitman
Moisture condition in treated wood exposed outdoors. A progress report after 5 years
1992 - IRG/WP 92-3720
Wood treated with water-borne preservatives, mainly CCA (copper, chromium and arsenic) and CCB (copper, chromium and boron) is often said to absorb more water than untreated wood. In laboratory tests this statement has not been confirmed (Johansson 1977). In 1986 a project was started to compare water absorption during outdoor exposure between wood stakes of pine, Pinus sylvestris L, and spruce, P...
M-L Edlund
Leaching results of shower test on L-joints with boric acid, bifluoride and TBTO rods
1995 - IRG/WP 95-50051
As part of the EC-project "Improvement of a local preservation process for wood products with reduced environmental impact", TNO has performed a leaching test on L-joints treated with pills with boric acid (Defence corner), bifluorides (Woodpil 55) and TBTO (Woodcap). The L-joints were exposed in an adapted shower test during 10 days, using 70 liters of water per day. The experiment is designed to...
P Esser, M J Boonstra, W L D Suitela, A J Pendlebury
Wood decay of Pinus sylvestris L. by marine fungi
1990 - IRG/WP 1463
Waterlogged wood decay by marine microorganisms represents a major problem for the conservation of wood structures of historic value. It is important to know which kind of decay affects the wood from a conservation point of view. Enzyme activities of 14 marine fungi belonging to several localities were studied. Also, the weight loss and the rot type suffered by the wood at a microscopic level were...
M C Escorial, M T De Troya, J E Garcia de los Rios
Moisture condition in treated wood exposed outdoors. A progress report
1989 - IRG/WP 3533
Wood treated with water-borne preservatives, mainly CCA (copper/chromium/arsenic), CCB (copper/chrome/boron) or CC (copper/chrome) is often said among users in Sweden to absorb more water than untreated wood. In laboratory tests this statement has not been confirmed but no field tests have been carried out in Sweden to study this phenomenon. In 1986 a project was started to compare water absorptio...
M-L Edlund, C E Sundman
Treatment of wood with formaldehyde. Acid catalysis of the reaction between formaldehyde and wood
1980 - IRG/WP 3146
Formaldehyde reacts with the free OH-groups in wood forming cross-linking bonds. The reaction can be brought about without any catalyst but in that case the activation energy is very high and high temperatures and long reaction times are needed. Normally, the reaction is catalysed by different acids. Acid catalysts, however, tend to degrade the cellulose and the wood matrix causing reduction in th...
T Vihavainen, K Piispanen, P Mansikkamäki
Recent developments in the treatment of sawn spruce by double vacuum impregnation
1978 - IRG/WP 3114
The timbers used for building purposes in the U.K. and on the Continent of Europe are mainly softwoods. The two types of wood most used are redwood (Pinus sylvestris) and whitewood (Picea abies or Picea sitchensis). Other species are used to a lesser extent when considerations such as a long length requirement or width requirement demand the use of, for example, hemlock, Douglas fir or Parana pine...
C T Kyte, L D A Saunders
The chemical nature of bis(tributyltin) oxide in Pinus sylvestris sapwood
1989 - IRG/WP 3508
Tributyltin compounds have been used for many years as wood preservatives. This study has provided, for the first time, an explanation for the previously reported dealkylation and/or volatilisation of the tributyltin species in, and from, Scots pine (Pinus sylvestris) sapwood. Thus, 119 Sn nuclear magnetic resonance studies have shown that, on impregnation into this timber, bis(tributyltin) oxide ...
S J Blunden, R Hill
Evidence for wood cell wall degradation by the blue stain fungus Botryodiplodia theobromae Pat
1994 - IRG/WP 94-10077
Botryodiplodia theobromae Pat., a world wide ubiquitous polyfagus sapstain fungus, was found able to destroy the cell walls of birch fibres (Betula verrucosa Ehrh.) but not Caribbean (Pinus caribaea var. hondurensis Barr. and Golf.) and Scots pine (Pinus sylvestris L.) tracheids. The fungus caused characteristic erosion of fibre cell walls similar to soft rot type 2; destruction of the S1 - S2 int...
O Encinas, G F Daniel
A technique for determinging the efficacy of wood preservatives for partially treated timber
1988 - IRG/WP 2322
A technique is described for determining the efficacy of wood preservatives either for certain wood species where a full penetration cannot be achieved by normal vacuum-pressure methods or for more permeable species to look at efficacy of treated zone in preventing decay of an untreated core. Both sapwood and heartwood planks of spruce (Picea abies) and pine (Pinus sylvestris) were treated by CCA ...
A J Nurmi
Étude in vitro de la colonisation et de la dégradation structurale du bois d'aubier de Pin sylvestre par la Mérule: Serpula lacrymans Schum. ex Fr. S. F. Gray
1979 - IRG/WP 198
The degradation of Scots pine sapwood cell walls by Serpula lacrymans, a brown rot fungus, is observed after various periods of exposure from two weeks to twelve weeks. The observation by microscopy shows that the hyphae of Serpula rapidly invade the wood tissues as cell wall degradation starts. That deterioration is not gradual, it is observed to be very irregular as well within the whole of the ...
D Dirol
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
Acetylated solid wood. Laboratory durability test (part 2) and field trials
1995 - IRG/WP 95-40048
Degradation of acetylated beech, pine and poplar by soft rot fungi was related to strength loss in a laboratory test. No strength loss was noticed for poplar acetylated to a weight percent gain (WPG) of more than 11.2% and beech with a WPG of 12.8%. Several field trials were set up to determine the durability of acetylated products in practice. They included a field test to determine the durabilit...
E P J Beckers, H Militz, M Stevens