Your search resulted in 732 documents. Displaying 25 entries per page.
The degradation of wood surfaces by dilute acids
1985 - IRG/WP 3326
Thin radial/longitudinal sections(~100 µ) of Corsican Pine (Pinus nigra) and Lime (Tilia vulgaris), were exposed to Sulphuric, Sulphurous, nitric, acetic, and formic acid at 40°C in the pH range 2-6. After about 3 months exposure to Sulphuric, nitric, acetic and formic acid at pH 2.0 Pine lost some 20-25% of its tensile strength. Losses in tensile strength due to sulphurous acid were greater bei...
P D Evans, W B Banks
Protection of cellulose string with biocide/water repellent mixtures
1997 - IRG/WP 97-30148
Protecting cellulosic materials in soil contact poses a formidable challenge. Many soil inhabiting bacteria and fungi that cannot degrade wood can nevertheless rapidly depolymerize cellulose once its protective lignin matrix is removed. As a result, cellulose based materials are rarely used in direct contact with soil. One exception, however, is the use of cellulose string to support climbing vine...
A B Chang, J J Morrell
Wood protecting chemicals for the 21st century
1993 - IRG/WP 93-30018
After assessing the past research with protection chemicals, this paper proposes future avenues for research and development in wood protection. Three scenarios are put forward for consideration. First, more is not better and future systems will emphasize combination formulations which enhance properties while providing biological efficacy. Second, current systems, especially those based on copper...
H M Barnes
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
Methods to determine the efficacy of three water repellent additives in waterborne preservatives
1997 - IRG/WP 97-30142
The paper describes the methods used to determine the efficacy of three different water repellent additives in waterborne preservatives. The wooden samples used are pine (Pinus sylvestris) and spruce (Picea abies) that are treated with 9 different waterborne preservatives in retention for hazard class 3 (above ground commodities). There are two sample sizes exposed, cladding boards (19 x 148 mm) w...
F G Evans, B Nossen, K M Jenssen, L R Wilhelmsen, G Fuglum
Comparative study of blue stain resistance of various types of wood stains after artificial and natural weathering
1992 - IRG/WP 92-2411
For the determination of the protective effectiveness of a preservative treatment against blue stain in service, artificial weathering has been proposed as an alternative for the natural weathering period of 6 months in the European standard EN 152. Research on a range of products and on complete finishing systems for external joinery was conducted during 1986-1990. It revealed that the decisions ...
J Van Acker, M Stevens, M Nys
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
Effect of leaching temperature and water acidity on the loss of metal elements from CCA treated timber in aquatic applications. Part 1: Laboratory scale investigation
1995 - IRG/WP 95-50046
In order to investigate the applicability of current prestandard leaching test methods, a series of experiments has been performed on CCA impregnated wood dealing with the influence of pH, temperature and agitation of the surrounding water. The leaching method used in this first part of the investigation is the European prestandard drafted by CEN/TC38/WG11, a short term dynamic leaching test under...
G M F Van Eetvelde, R J Orsler, G E Holland, M Stevens
Algal growth resistance of paints for coating of wood; a laboratory study
1997 - IRG/WP 97-10213
Twelve paints were tested for resistance against algae. In addition, one algicidal compound commercially used for remedial treatments of algal growth on paints was tested for its effectiveness for prevention of algal growth. An agar diffusion bioassay was employed in which paint films on filter paper discs were placed on mineral salt medium and sprayed with an algal suspension containing a mixture...
J Bjurman
Penetration and absorption of water-borne preservatives in conifers from the Western United States: A preliminary report
1988 - IRG/WP 3475
The treatment of most softwoods from the western United States with waterborne chemicals poses a major challenge. Although many of these species are commercially treated with waterbornes, there is considerable debate about their treatability. At present, there is little or no information on the treatability of western wood species with waterborne chemicals. The lack of accurate treatability inform...
S Kumar, J J Morrell
Aquatic toxicity research of structural materials
1998 - IRG/WP 98-50114
Continuing from preliminary results reported on the aquatic toxicity of some tropical hardwoods under high hazard conditions, a more comprehensive research study is set-up in order to assess the environmental toxicology of various structural materials in water applications. Hazard class 4 preservative treated wood is tested for its toxic response on a battery of aquatic test organisms, next to con...
G M F Van Eetvelde, S De Geyter, P Marchal, M Stevens
PCP in aquatic environments arising from historic contamination at wood processing and preservation sites
1995 - IRG/WP 95-50040-14
Three different studies are reported that assess the impacts of Pentachlorophenol (PCP) in aquatic environments arising from its historic use at sawmilling and wood preservation sites. These studies involved New Zealand wood processing facilities, and collectively they aimed to measure the transport of PCP from sawmill sites into the aquatic environment, determine the background environmental conc...
J S Gifford, P N McFarlane, M C Judd, S M Anderson
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
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
Influence of water soluble extractives on CCA fixation and leaching performance of red maple and red oak
1997 - IRG/WP 97-30133
We have observed several peculiarities in relation to CCA fixation in red maple and red oak woods such as high variability in fixation rates and leaching performance in maple and precipitate formation in solutions expressed from CCA treated red oak wood blocks at different stages of fixation. We have postulated that the extractives could be the factor of influence, as this has already been reporte...
T Stevanovic-Janezic, P A Cooper, Y T Ung
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
IRG/COIPM INTERNATIONAL MARINE TEST - To determine the effect of timber substrate on the efectiveness of different preservatives in sea-water: Coding scheme
1976 - IRG/WP 420
It was agreed in Wildhaus on 15 May 1976 that preparations for the test detailed in Document No: IRG/WP/414 should commence immediately, but that initially only two water-borne preservatives should be used - a copper/chrome/arsenic (CCA) and a copper/chrome/boron (CCB) formulation respectively. PRL, England (R Cockcroft) would be responsible for supplying only the reference species treated with th...
Anonymous
Moisture content of logs under sprinklers
2000 - IRG/WP 00-40157
Logs are kept under sprinklers during storage for avoiding the development of sapstain fungi. According to literature, sapstain fungi do not develop if the moisture content is above 120%. It is supposed that, the water sprinklers maintain the log's moisture content above this value, but, very often, sapstain is found on sawn lumber cut from these logs. Logs are harvested and transported t...
M C Rose, A M Briones, M Fernández
The future for chromium in wood preservation
1985 - IRG/WP 3332
Most water-borne preservatives contain CrVI compounds, originally to reduce corrosion although now also to improve toxicant fixation. Chromium contributes to preservation and this is recognised in, for example, New Zealand and USA where chromium contents are included in calculations of overall preservative activity of CCA formulations, but chromium may also have anti-stain and joinery (millwork) p...
B A Richardson, T R G Cox
A substantively bonded water repellent treatment based on chromium carboxylates
1985 - IRG/WP 3344
Chromium carboxylates soluble in toluene have been synthesised and applied to Scots pine (Pinus sylvestris) sapwood. Without any further treatment, the compounds may be readily leached from wood surfaces with toluene. After a period of heating however, they become fixed to the cell wall, substantial amounts being resistant to leaching even under reflux conditions for several hours. Treatment of wo...
J K Wright, W B Banks, W J Eilbeck
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