Your search resulted in 73 documents. Displaying 25 entries per page.
The use of spruce for transmission poles
1973 - IRG/WP 326
A series of preservative treatments with creosote using Lowry and Rueping schedules was undertaken. From these treatments the most suitable impregnation conditions for water stored Sitka spruce (Picea sitchensis) and Norway spruce (Picea abies) transmission poles were determined. Preservative distribution and permeability values for poles of both species were used to decide the optimum season and ...
J A Dunleavy, D J Balfe, J P Prendergast
Water-storage for improving the permeability of sugi (Cryptomeria japonica D. Don)wood
1999 - IRG/WP 99-40129
The viable bacterial counts in sapwood and intermediate wood of sugi bolts increased immediately after floated in a fresh water pond. Bacterial invasion into the heartwood was not detected apparently during water-storage for 36 weeks, although a few bacterial species have inhabited in freshly-cut heartwood samples. The bacterial species isolated from the water-stored bolts were almost Gramnegative...
S Ohta, S Doi
Penetration and distribution of styrene in pressure treated hardwoods
1997 - IRG/WP 97-40094
A styrene impregnation method was used to compare liquid distribution in several species as affected by flow direction, sapwood/heartwood, and method of impregnation. Twenty-five mm ( 1") cubes were cut from the sapwood and heartwood of red maple (Acer rubrum), white birch (Betula papyrifera), yellow poplar (Liriodendron tulipifera), trembling aspen (Populus tremuloides), red oak (Quercus rubra), ...
P A Cooper, T S Janezic, U Srinivasan, A Omidvar
Studies on the permeability of Norway spruce (Picea abies)
1987 - IRG/WP 2295
It is well known that the bordered pits play a dominating role for liquid transport in softwoods. The mechanism behind pit aspiration during drying or heartwood formation seems to be well understood. The reason why the fixation of the membrane (torus) to the pit opening remains almost irreversible is, however, still unclear. A technique has been developed combining so-called "solvent exchange dryi...
I Johansson, K Nordman-Edberg
Field and greenhouse testing of window joinery of pine and spruce treated with LOSP
1991 - IRG/WP 3658
Norwegian window frame components of full size were double vacuum-treated with TBTN and TBTO, and connected as 'L-joints' and subsequently coated with stains. The corner sections were exposed (out of ground contact) both in field (temperated coastal climate, Taastrup, Denmark) and in a greenhouse (Uppsala, Sweden). The window frame L-joints of spruce (Picea abies Karst.) - treate...
F G Evans, B Henningsson, E Borsholt
Leachability of didecyldimethylammonium chloride (a quaternary ammonium compound) from four wood species
1982 - IRG/WP 3204
Sapwood blocks prepared from red pine, ponderosa pine, southern yellow pine and hem-fir (a commercial mixture of western hemlock and amabilis fir) were treated with didecyldimethylammonium chloride, (an alkylammonium compound, AAC). After oven drying the blocks were vacuum impregnated with distilled water and subjected to a static leach cycle for 48 hours. The leachate was analyzed and the amount ...
J N R Ruddick, A R H Sam
The effect of water storage on the cell-structure of Sitka spruce (Picea sitchensis) with reference to its permeability and preservation
1970 - IRG/WP III 3A
Commercial treatment trials with full sized transmission poles have shown that water storage considerably improves the permeability of Sitka and Norway spruce. These results were confirmed by laboratory measurements which showed that in the sapwood of ponded Sitka spruce there is a vast improvement in permeability in all three grain directions. Heartwood permeability does not seem to be affected t...
J A Dunleavy, A J McQuire
Collaborative field trial out-of-ground contact
1982 - IRG/WP 2179
At the 12th meeting of the IRG in Sarajevo, Yugoslavia it was decided after considerable discussion that the best way to proceed with the work of the subgroup was to centre it around a co-operative field trial based on the L-joint test detailed in IRG/WP/2157. At the same time it was agreed that interested laboratories would also conduct their own methods, particularly the German planner test and ...
D J Dickinson, A F Bravery, J K Carey
Co-operative research project on L-joint testing. Sampling after 18 months exposure
1984 - IRG/WP 2233
In September 1983, Document No: IRG/WP/2208 was distributed giving guidance on sampling after 8 months exposure (due 1 December 1983 for those L-joints exposed on schedule on 1 April 1983), and including tables on which to record the test results. No major problems have been notified to Princes Risborough Laboratory concerning the sampling method. It is therefore proposed that the next sampling, a...
J K Carey, A F Bravery
A comparison between high and conventional incision densities for improving preservative treatment of Douglas-fir heartwood lumber
1993 - IRG/WP 93-40009
Incising is required for the preservative treatment of most wood species from the western United States; however, there is considerable debate about the density of incisions required to achieve adequate treatment. Previous studies have shown that the incision effect on treatment is relatively narrow, suggesting that incision densities should be significantly increased over current practices and st...
S T Lebow, J J Morrell
Co-operative research project on L-joint testing. Progress report to March 1986
1986 - IRG/WP 2272
Further sets of data received from CTFT (France) after 18 months exposure, BAM (Germany) after 18 months exposure, STU (Sweden) after 9.5 months exposure and TI (Denmark) after 12 and 17.5 months exposure are presented and discussed in conjunction with data previously reported. The new data are generally in agreement with those presented previously and indicate the major difference between the co-...
J K Carey, A F Bravery
Improved preservative penetration of spruce after pre-treatment with selected fungi. II. Creosote treatment, analysis and strength testing
1998 - IRG/WP 98-40106
This paper describes the creosote treatment and analysis of logs pre-treated with selected fungal agents as a method of increasing the porosity of the wood prior to preservative treatment. The paper also reports the subsequent strength testing of the timber to evaluate the effects of the fungal pre-treatment on the structural integrity of the wood.
European spruce logs were pre-treated with eithe...
E J Tucker, A Bruce, H J Staines, B Rosner, K Messner
Microwave modification of wood properties - Improvements in wood permeability
2000 - IRG/WP 00-40181
A new method of microwave (MW) wood modification is described. Microwave irradiation of timber provides an improvement in wood permeability mainly in the radial and longitudinal directions. This is achieved by physically modifying ray cells and forming a large number of cavities in the radial - longitudinal planes. More extensive MW irradiation of different species transforms the wood into a new m...
G Torgovnikov, P Vinden
Co-operative research project on L-joint testing. Progress report to March 1985
1985 - IRG/WP 2236
It was originally intended that each participant would expose L-joints in the main trial on 1 April 1983 with the first sampling at 8 months (1 December 1983) and the second sampling at 18 months (1 October 1984). In the event, some participants have had to vary this schedule. Results after the first sampling have been received from CTFT (8 months), BAM (12 months) and Sipad-IRC (8 months) and aft...
J K Carey, A F Bravery
Mercury porosimetric evaluation of the impregnability of wood
1985 - IRG/WP 2234
Mercury porosimetric measurements for specimens of a given length can not be used to evaluate the treatability of wood. The reason is that the permeability for low permeable woods deviates from Darcy's law with the specimen length. This paper presents a method of evaluation which respects this phenomenon in indicating not only pore size but also a factor describing the pore size as a func...
J P Hösli
Rubberwood anatomy and its influence on gaseous permeabilit
1993 - IRG/WP 93-40005
The anatomical structure in several rubberwood (Hevea brasiliensis Muell. - Arg.) samples was examined by use of a Cambridge Stereoscan 600 scanning electron microscope. A series of electron micrographs is presented which illustrate those features anticipated as having an influence on permeability. A series of gas permeability experiments were performed on oven dried samples of rubberwood to deter...
A J Pendlebury, J A Petty
Evaluation of the permeability of fast grown wood species
1995 - IRG/WP 95-40042
The low natural durability of certain species of wood, implies the need for applying a protecting treatment to increase its life in service. Because of this, a knowledge of the permeability properties of the wood is desired. In this work, a simple and reliable method to evaluate the wood permeability is presented. For that, we have been used fast grown species, with low natural durability, Poplar ...
M T De Troya, A M Navarrete, E Sanchez, J E Garcia de los Rios, E L Rodríguez Trobajo
The association of bacteria with the increased permeability of water-stored spruce wood
1973 - IRG/WP 325
A microbiological investigation was undertaken to check our earlier work on patterns of bacterial counts and pH changes in water-stored wood. A survey of industrial activity was conducted upstream from the storage site with a view to explaining the existing bacterial flora. Further experiments were carried out with spruce bolts in enclosed tanks, using lake water with its natural bacterial flora a...
J A Dunleavy, J P Moroney, S E Rossell
Co-operative research project on L-joint testing. Sampling after 4 years exposure
1987 - IRG/WP 2274
In September 1983, Document No: IRG/WP/2208 was distributed giving guidance on sampling after 8 months exposure and including tables on which to record the test results. Similarly in September 1984, Document No: IRG/WP/2233 was distributed concerning sampling after 18 months exposure. No major problems have been notified to Princes Risborough Laboratory concerning the sampling method. It is theref...
J K Carey, A F Bravery
The resistance of timbers to impregnation with wood preservatives
1979 - IRG/WP 3137
It is anatomical structure which determines liquid flow rate within different timber species. This cannot be deduced from properties such as density or rate of growth, and can only be found by experiment. A standard test has been in use at the Princes Risborough Laboratory for many years, employing a pressure-impregnation treatment, and a large number of timbers have been studied. The test consist...
Anonymous
Permeability measurements on surface layers for detecting wood with abnormally high permeability
1988 - IRG/WP 2298
Wet storage of timber during the warm period of the year may lead to an increased permeability of the wood, an undesirable phenomenon for several wood industries and also for many end-uses. Neither before nor after drying, such wood with "wet storage damage" can be visually distinguished from wood with a normal permeability. A non-destructive method for inspecting the permeability of surface layer...
J B Boutelje, G Hägglund
Mould growth and permeability in relation to wet-storage
1989 - IRG/WP 1414
The positive influences of wet-storage of roundwood to avoid attack by blue stain fungi and insects and to avoid cracking of wood during storage are well documented. Comparatively little information is, however, available on the effects on microbial susceptibility of the material after the storage period. The permeability of the wet-stored and the non-wet-stored material was determined. Wood block...
J Bjurman, E L Holappa
Amenability of radial permeability of Sitka spruce (Picea sitchensis (Bong.) Carr.) as affected by aspects of cell ends in uniseriate ray parenchyma tissue
2003 - IRG/WP 03-40252
The principal objective of this article was to recognise and understand the amenability of ray parenchyma cell ends (end platform) in uniseriate ray tissue to influence the radial permeability of Sitka spruce (Picea sitchensis (Bong.) Carr.) by examination of most (Queen Charlotte Islands in Rhondda, South Wales) and the least (South Oregon in Dalby, North-East England) seed origins that grown in ...
I Usta, M D C Hale
Changes in transverse wood permeability during the drying of rimu and radiata pine
1990 - IRG/WP 3636
When softwoods are dried and subsequently impregnated with waterborne preservatives two problems frequently occur, preservative screening of multi-salt preservatives and difficult re-drying. To study the causes, the permeability of rimu and radiata pine wood has been measured along the three principal directions. The radial and tangential permeabilities of the green sapwood of the two species were...
R E Booker
Radial flow of Bornmullerian fir (Abies bornmulleriana Mattf.) as affected by wood tapering and the condition of end wall structure of uniseriate ray parenchyma cells
2008 - IRG/WP 08-40441
Amenability to radial permeability of Bornmullerian fir (Abies bornmulleriana Mattf.) was studied on the base of the effects of wood tapering and the structure of end walls of uniseriate ray parenchyma cells. The results showed that the most remarkable culprits of the greatest fluid uptake (as the percentage of void volume filled by the fluid in the radial flow direction, RVVF%) are the lesser woo...
I Usta, S Aslan