Your search resulted in 40 documents. Displaying 25 entries per page.
Bordered Pit Imaging
2012 - IRG/WP 12-10773
New findings about bordered pits will be presented using the latest microscopy techniques. Three-dimensional imagery at the nanolevel is used, and short 3-D movies will shown as part of the discussion on this topic to reveal new features that have not previously been reported in pits. The implications for both microorganism penetration through lignified cells as well as preservative penetration i...
D Mascheck, B Goodell, H Militz, M Lessard, J Jellison
Ultra-structural observations on the degradation of wood surfaces during weathering
1987 - IRG/WP 2280
Radiata pine (Pinus radiata D. Don) sapwood was converted into blocks with a transverse face about 5 mm square and measuring 8 mm longitudinally. Transverse (T.S.), Radial (R.L.S.) and Tangential (T.L.S.) surfaces were prepared and specimens exposed to the weather inclined at 45° facing equatorially for periods of between 20-60 days. After 30 days exposure erosion of the middle lamella was observ...
P D Evans, S Thein
A review of the configuration of bordered pits to stimulate the fluid flow
2005 - IRG/WP 05-40315
As the bordered pits have generally been thought to have an influence on the refractory nature of softwoods, structural behaviour of this conducting pathways is discussed according to the published literature. Various theories on the role of bordered pits to axial flow are expounded in respect to preservative treatment. Pit aspiration is also reviewed....
I Usta
Water sprinkled pine wood: A microscope study on boards showing streaking
1993 - IRG/WP 93-10033
Boards sawn from the outer sapwood of pine lumber previously water sprinkled for periods of 10-18 weeks and kiln dried, showed streaking after staining. Two types of enhanced stain uptake were noted: 1) a more concentrated and localized form after 10 weeks and 2) a more diffuse type which developed in later stages of water sprinkling. Areas showing enhanced stain uptake were examined using light a...
G F Daniel, T Elowson, T Nilsson, A P Singh, K Liukko
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
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
Wood structure in relation to excessive absorption - a literature survey
1971 - IRG/WP 300
This literature study, composed in connection with 'the structure of wood in relation to the excessive absorption', started from the idea that the subject only could be dealt with successfully if the structure was taken into account in relation to a normal absorption pattern in so far as this knowledge can enlighten the understanding of the abnormal situation. The normal penetrat...
S M Jutte
Hydrolysis of bordered pits during colonization of conifers by brown-rot fungi
1995 - IRG/WP 95-10103
Brown-rot decay results in rapid reduction in degree of polymerization (DP) of holocellulose with concomitant strength loss (MOR) without removing lignin. Development of new methods of wood protection will require focusing on early events in the sequence of depolymerization. Bordered pit membranes (sapwood) represent a readily available source of non-lignified carbohydrate, ie. pectin and cellulos...
F Green III, J L Tschernitz, T A Kuster, T L Highley
Use of Variable Pressure Scanning Electron Microscopy for in situ Observation of Degradation of Wood Surfaces during Artificial Weathering
2012 - IRG/WP 12-20489
Variable pressure scanning electron microscopy (VPSEM) is capable of observing electrically non-conductive materials like wood without the need to render the surface conductive by applying a coating of gold, platinum or carbon. Hence, there is the possibility that VPSEM could be used to non-destructively follow the structural changes occurring at wood surfaces during weathering, because specimens ...
F Hatae, Y Kataoka, M Kiguchi, H Matsunaga, J Matsumura
List of Members 1976
1976 - IRG/WP 552
IRG Secretariat
List of Members
1972 - IRG/WP 505
IRG Secretariat
Resistance of Alstonia scholaris vestures to degradation by tunnelling bacteria
1992 - IRG/WP 92-1547
Electron microscopic examination of vessels and fibre-tracheids in the wood of Alstonia scholaris exposed to tunnelling bacteria (TB) in a liquid culture showed degradation of all areas of the secondary wall. The highly lignified middle lamella was also degraded in advanced stages of TB attack. However, vestured pit membranes and vestures appeared to be resistant to degradation by TB even when oth...
A P Singh, T Nilsson, G F Daniel
Annotated check-list of the Limnoriidae
1990 - IRG/WP 4160
The crustacean isopod family Limnoriidae comprises 51 species of marine borers. A list of species is provided, together with notes on the species known distributions, depth ranges, and habitats. There is also a brief account of the phylogeny of the group....
L J Cookson
List of Members 1 November 1974
1974 - IRG/WP 533
IRG Secretariat
List of Members and Sponsors
1980 - IRG/WP 5115
IRG Secretariat
Safety clearance of wood preservatives in United Kingdom
1977 - IRG/WP 398
In the United Kingdom the principal route of control of pesticides is through the Pesticides Safety Precautions Scheme (PSPS) which is a non-statutory scheme agreed between government ministries and departments (referred to as "Departments") and associations representing the pesticide industries. The scheme formally began in 1957 covering those pesticides and related substances used in agriculture...
J M Baker
List of Members and Sponsors
1985 - IRG/WP 5217
IRG Secretariat
List of Members 1969
1969 - IRG/WP A 3
IRG Secretariat
List of Members and Aims 1978
1978 - IRG/WP 578
IRG Secretariat
List of Members
1970 - IRG/WP A 3A
IRG Secretariat
List of Members 1 January 1974
1974 - IRG/WP 524
IRG Secretariat
List of Members and Sponsors 1983
1983 - IRG/WP 5190
IRG Secretariat
List of Members 1975
1975 - IRG/WP 544
IRG Secretariat
List of Members of IRG and contributing workers proposed for membership in IRG/WP/ - I - Sub-group 5
1976 - IRG/WP 154
S Cymorek
List of Members and Sponsors 1982
1982 - IRG/WP 5172
IRG Secretariat