Your search resulted in 512 documents. Displaying 25 entries per page.
Microscopic FT-IR depth profiling study of photo-induced degradation in wood
2001 - IRG/WP 01-20229
FT-IR microspectroscopy was used to monitor the changes in the chemical composition at various depths from the photo-irradiated surface of sugi (Cryptomeria japonica D. Don) sapwood. The radially cut wood face was exposed to artificial solar radiation from a xenon light source at 375 Wm-2 (in a 300 - 700 nm spectral range) for up to 600 h. The IR depth profiling spectra showed that the artificial ...
Y Kataoka, M Kiguchi.
Surface protection of wood with titanium, zirconium and manganese compounds
2005 - IRG/WP 05-30376
Thin radiata pine veneers were treated with a range of titanium, zirconium and manganese compounds and exposed to natural weathering. Veneer weight and tensile strength losses were used to assess the protective efficacy of the compounds. The oxidative manganese compounds potassium permanganate and manganic acetate restricted both weight and tensile strength loss of treated wood veneers during weat...
K J Schmalzl, P D Evans
Preliminary investigation on the natural durability of Guayule (Parthenium argentatum)-based wood products
2000 - IRG/WP 00-40154
Conventional preservatives used to protect wood from insect and microbial damages are presently of major concern to human health and the environment. Finding alternative and economical preservatives has not been successful. Previous studies have shown that the resinous material extracted from the guayule plant (Parthenium argentatum, Gray) has both insect- and microbial-resistant properties. Unfor...
F S Nakayama, P Chow, D S Bajwa, J A Youngquist, J H Muehl, A M Krzysik
Impact of leachates from CCA- and copper azole-treated pine decking on soil-dwelling invertebrates
2002 - IRG/WP 02-50183
This study assessed the short-term effects on non-target soil invertebrates of leachates from a naturally durable hardwood and timber treated with two copper-based wood preservatives. Natural rainwater leachates from kwila decking, and radiata pine-decking treated with CCA or copper-azole, were collected and applied on mown lawn soil in Brisbane, Queensland. The soil study consisted of 5 treatment...
N Crumière, A House, M J Kennedy
FTIR studies on the weathering of didecyldimethylammonium compound (DDAC) treated wood
1993 - IRG/WP 93-30013
Wood treated with alkylammonium compounds (AACs), such as DDAC, weathered more rapidly than untreated wood. In order to examine the influence of DDAC treatment of wood on its weathering, treated and untreated microtomed sections of southern yellow pine earlywood of various thicknesses, were prepared and weathered for approximately one month. The changes in these samples were monitored using FTIR. ...
R Liu, J N R Ruddick
An analysis of the effects of some factors on the natural durability of pine (Pinus sylvestris L.) and spruce (Picea abies Karst.)
1986 - IRG/WP 1279
The effects of some factors on the natural resistance of pine and spruce sapwood against fungal decay and against attack of house-longhorn beetle larvae have been studied in laboratory tests and the results are evaluated by analysis of variance and regression analysis. Following conclusions were reached: Wood from summer-felled trees did not have a lower inherent natural durability against fungal ...
J B Boutelje, T Nilsson, S Rasmussen
A comparison of analytical and visual techniques used for assessment of weathering properties of chromium and copper azole treated timber
1994 - IRG/WP 94-20023
The weathering properties of preservative treated timber were studied by measuring surface lignin loss and by microscopic examination after weathering, and results were related to qualitative assessments of visual appearance after weathering. Measurement of relative rates of delignification of untreated and preservative treated timber obtained by FTIR analysis, and weight loss determined on thin v...
J A Cornfield, M D C Hale, G Fettis
Durability of some alternatives to preservative treated wood
2004 - IRG/WP 04-30353
The environmental discussion in Sweden has lead to an increasing use of naturally durable domestic wood species and wood treated according to alternative methods for use above ground. A number of these alternatives have been tested according to field- and laboratory tests and compared to wood treated with preservatives for above ground use. Seven untreated wood species, four alternative wood treat...
M-L Edlund
A 53-year old field trial to evaluate the performance of a range of chemical treatments on eucalypt poles
1989 - IRG/WP 3526
Hardwood pole stubs of Eucalyptus maculata, Eucalyptus pilularis, Eucalyptus saligna and Eucalyptus paniculata were examined for termite attack and fungal decay after 53 years in ground contact. The trial compared eight different chemical treatments with untreated pole stubs of the four species investigated. Untreated Eucalyptus paniculata, a Class I durability species, performed particularly well...
R S Johnstone, R A Eaton
Shorter-term biological control of wood decay in pre-seasoning pine roundwood as an alternative to chemical methods
1992 - IRG/WP 92-1555
Previous studies on the long-term control of decay in creosoted transmission poles, using Trichoderma and other antagonistic moulds, have met with limited success. However, it is possible biological control is more suited to control of decay on shorter time scales. An earlier study, focusing on pre-seasoning treatment of transmission poles showed that favourable porosity increases could be brought...
M W Schoeman, D J Dickinson
Accelerated testing for out of ground contact using natural biological preconditioning: Part 2
1997 - IRG/WP 97-20108
Small blocks of scots pine sapwood were treated, buried in vermiculite and exposed to natural microbial colonisation during outdoor exposure prior to laboratory decay testing. An EN 84-type leach trial was carried out on unexposed samples. Periodic microbial isolations, moisture content, permeability and weight loss tests were also conducted. The experiment ran for 12 months. The colonisation of t...
S Molnar, D J Dickinson, R J Murphy
Preliminary observations of the effect of growth ring orientation on the surface checking of flat sawn Southern pine decking
2005 - IRG/WP 05-20313
Checking in decking timber is a serious defect and methods of reducing its severity are required to ensure that wood can compete with alternative decking materials. The first aim of this research was to test the hypothesis that flat sawn Southern pine decking boards with growth rings oriented concave to the exposed surface will develop less severe checking when exposed outdoors than similarly expo...
K Urban, P D Evans
Resistance of twenty-five species of timbers to marine borer attack at Visakhapatnam, east coast of India
1994 - IRG/WP 94-30036
Observations on the natural resistance of 25 species of timbers to marine borer attack for a twelve month period at the fishing harbour, Visakhapatnam, East Coast of India, indicate that none of the species was free from borer attack. The damage was mainly by teredinids - Teredo furcifera and Lyrodus pedicellatus. Martesia striata, Teredo parski, Bankia campanellata and Lyrodus bipartitus were als...
K S Rao, M Balaji, V V Srinivasan
The present status of wooden catamarans of the Indian Coast
1997 - IRG/WP 97-10231
Catamarans (a.k.a. kattumarams) are the most widely used fishing craft in India, and hundreds of thousands of poor, traditional fishermen depend on these vessels for their livelihood that are almost made entirely of wood. In recent years, acute shortages and phenomenal increases in prices of timber species used in catamaran fabrication have been reported, causing great hardship to the user communi...
K S Rao
Impregnation of timber with tannin as a mean of improving its dimensional stability
1992 - IRG/WP 92-3695
The results of a joint project carried out at the Timber Division of LNEC under the 2nd research programme of the CEC DGXII - "Wood as a renewable raw material" entitled "Stabilization of wood by impregnation processes" is presented. Pieces Maritime pine timber was impregnated with tannin under pressure to see if the treatment with tannin improved the behavior of wood regarding its dimensional sta...
J S Machado
Effects of pre-harvest girdling on selected properties of red pine, red maple and Eastern larch
1999 - IRG/WP 99-40137
Trees of three species - tamarack (Larix laricina), soft maple (Acer rubrum) and red pine (Pinus resinosa) - were girdled immediately below the crown,one to two years before felling. The wood from these trees was compared with wood taken from un-girdled control trees felled at the same. Sapwood and heartwood, from the controls, and from above and below the girdle of treated trees, were examined fo...
A Taylor, P A Cooper
Supply of wooden transmission and telephone poles in Tanzania: Problems and possible solutions
1987 - IRG/WP 3424
The eucalypts which have been used widely for utility poles for more than 30 years have dwindled remarkably from traditional supply areas. Consequently, pole-using authorities are considering importing poles from abroad. This alternative is considered unrealistic and costly. The aims of this paper are: - to dispel fears of pole scarcity and to show that an abundant resource of a variety of tree sp...
K K Murira, S A Diwani
Natural decay resistance of some lesser known /used timber species from the forests of Tanzania
2005 - IRG/WP 05-10557
In order to manage the Tropical forest in a sustainable manner and increase the resource base for their wood industries, many Tropical African timber producing countries including Tanzania are promoting the many lesser known/used timbers in their forests as alternative sources of wood to the over-exploited primary timber species. Four lesser known/utilized timber species from the forests of Tanzan...
S A Amartey, P R Gillah, R C Ishengoma, J Gabriel, D H Kitojo
Whitewood - An external joinery timber?
1975 - IRG/WP 253
The timber used traditionally for softwood joinery in the UK is redwood (Pinus sylvestris). In the past its ready availability in the desired sizes and quality and its durability in service encouraged little competition. However, the past decade has seen some erosion of this position, particularly through the increased proportion of sapwood in redwood supplies. Since the sapwood is less durable th...
J W W Morgan
The use of lap-joints in natural durability testing: moisture content development during 36 months outside exposure trials
2000 - IRG/WP 00-20217
Lap-joint trials (following European Standard ENV 12037) were set up with 11 different softwood and hardwood species. The main aim was to evaluate the suitability of this test standard (developed for testing wood preservative effectiveness) for natural durability testing. The moisture development has been followed during a 36 months period. In this paper, the outcomes of different moisture content...
H Militz, C J Bloom
Ability of heartwood extractives to inhibit the growth of a bacterial symbiont of Teredo navalis
2000 - IRG/WP 00-10369
Shipworms are important destroyers of wood in the marine environment, and wood users have long sought methods for preventing or limiting their attack. While heavy -duty wood preservatives are highly effective against these organisms, there is increasing concern about risks to non-target organisms. This has resulted in a gradual shift away from broadly toxic materials to either alternative material...
C S Love, A R Sipe, S C Cary, J J Morrell
Biocidal property of the phenolic fraction of ethanol extractives of Hopea parviflora heartwood
1993 - IRG/WP 93-30003
Natural resistance of some species of timber to fungal decay and insect damage (particularly termite) is ascribed toxic nature and quantity of certain chemical substances present in the cell wall of heartwood. These chemical substances generally known to be Phenolic and Polyphenolic compounds (Rao 1982). Earlier investigations on extractives were mainly in relation to resistance of timber to decay...
R V Krishnan, K S Theagarajan, H S Ananthapadmanabha, M Nagaraja Sharma, V V Prabhu, H C Nagaveni
Preliminary indications of the natural durability of Spruce bark board
1999 - IRG/WP 99-10312
A board material made from pressed bark, with no added adhesive, has been developed by Forintek's composites group and tested for durability by Forintek's treated-wood group and the University of Hawaii. This material was also manufactured with veneers in a one-step process. Since one role of bark on the tree is protection against pests and diseases, barkboard was expected to hav...
P I Morris, J K Grace, G E Troughton
The critical timing of inspections for field testing of natural durability
1994 - IRG/WP 94-20018
An overestimation of performance will almost always result if the condition of a specimen is considered to be attained at the precise time that an inspection is carried out. The time at which the condition is actually attained, referred to in this document as the "Condition time", is best considered to be halfway between two successive inspections. The requirement to obtain data that is relevant t...
J D Thornton
Assessment of untreated Papua New Guinean timbers against subterranean termites. Progress Report 1
1990 - IRG/WP 1436
Eight major commercial timber species (Intsia palembanica, Pometia pinnata, Homalium foetidum, Dracontomelon dao, Calophyllum spp., Eucalyptus deglupta, Nothofagus spp., and Alstonia scholaris) were exposed in ground contact against termites. Five replicates of heartwood stakes of 25x25x250 mm³ of each species were randomly embedded in the soil. Results after 24 months exposure showed that Kwila ...
M Rokova, H C Konabe