Your search resulted in 32 documents. Displaying 25 entries per page.
The proposal for optimalization of the agar-block method for wood preservatives fungitoxic evaluation
1995 - IRG/WP 95-20065
On the base of own research and other scientists results the proposal for optimalization of agar-block method was presented by:
- selection of test fungal species and strains and central distribution of their pure cultures,
- change of the treatment and control samples exposure procedure,
- application of mathematical estimation of toxic value results,
- shortening the duration of fungitoxic t...
J Wazny
Evaluation of two populations of Reticulitermes santonensis De Feytaud (Isoptera) by triple mark-recapture procedure
1997 - IRG/WP 97-10237
The optimisation and use of biocides is linked to the improvement in our understanding of the target organism. With this in mind we have studied 2 populations of the termite Reticulitermes santonensis De Feytaud. The first inhabiting an urban territory, the trees lining Ave. Boutroux in Paris. The colony has been estimated at 1,200,000 +/- 130,000 insects by triple mark-recapture procedure, foragi...
I Paulmier, B Vauchot, A-M Pruvost, C Lohou, M Tussac, M Jéquel, J-L Leca, J-L Clément
Soft rot cavity widening - A consideration of the kinetics
1984 - IRG/WP 1227
Studies on the micromorphology of soft rot cavity formation by Phialophora hoffmannii in birch using time-lapse cinemicrography are briefly outlined. A mathematical model is constructed to describe the cavity widening process, particularly changes in the surface area of a hypothetical cavity during enlargement. On comparison with observed data it is concluded that the rate of cavity widening is de...
M D C Hale, R A Eaton
Estimation of service life of durable timber species by accelerated decay test and fungal cellar test
2002 - IRG/WP 02-20249
Many kinds of durable wood species for outdoor uses has been imported from all over the world to Japan. However information on the natural durability of these species is not sufficient to estimate the service life of them in the climate of Japan. Highly durable species such as Jarrh, Teak, Ipe, Ekki, Selangan batu, Red wood, Western red cedar showed no significant percent mass losses by accelerate...
K Yamamoto, I Momohara
Computerised data acquisitioning, handling and processing in wood preservation studies
1984 - IRG/WP 2218
The computerisation of data acquisitioning, handling and processing in weathering studies on wood treated with protective coatings is discussed. An integrated system comprising a data base, statistical package and a custom written graphical processor is explained. Two treatments are compared and the correctness of a mathematical weathering model is evaluated....
T Rypstra, K Vos
Estimation of effective diffusion path lengths in wood by swelling studies
1989 - IRG/WP 3524
The effective average distance that a solute must diffuse to penetrate the cell wall matrix following pressure treatment is estimated from the rate of swelling of wood, vacuum treated with water. It is assumed that the diffusion paths are similar for water and a solute such as a wood preservative component. Since bound water diffusion coefficients for water in wood have been estimated by others, t...
P A Cooper, R Churma
Modelling the control of decay in freshly felled pine poles
1997 - IRG/WP 97-10206
In a recent study investigating control of decay in freshly felled pine utility poles, it became apparent that the efficacy of different treatment methods was strongly related to the size of the material being treated. A topical application of 5% w/v disodium octaborate tetrahydrate (DOT), brush applied to the cut surfaces of logs with otherwise intact bark was just as effective at excluding white...
M W Schoeman, W Van der Werf, J F Webber, D J Dickinson
Estimation of the population of a sound colony of Coptotermes lacteus (Froggatt)
1988 - IRG/WP 1353
Selecting an area with a high termite hazard is deemed essential in locating field sites in order to screen potential termiticides and wood preservatives. Yet, quantifying termite populations in such sites remains imprecise. There are major problems associated with estimating populations of termites in mound colonies (either free-standing or in trees), and these are briefly discussed. In this pape...
D M Ewart, J R J French
The mathematical study of test plot data
1987 - IRG/WP 2282
It has long been desirable to have a mathematical expression, which, by the insertion of statistically derived constants, would describe the behavior of test specimens in service. The philosophy of such expressions is briefly discussed, and the history of the concept is outlined. The modern approach to the problem dates from the graphical presentation of dosage-response and deterioration curves by...
W H Hartford
Preliminary modelling of methylisothiocyanate movement through Douglas fir transmission poles
1988 - IRG/WP 3466
Methylisothiocyanate is a volatile solid that is the active ingredient of several registered and experimental wood fumigants. Information on the sorption and diffusion of this chemical in Douglas-fir heartwood and sapwood was used to develop a two-dimensional model of fumigant movement within a single horizontal cross-section of a transmission pole. The model indicated that dry wood (14% MC) stron...
A R Zahora, P E Humphrey, J J Morrell
Estimation of oral toxicity of boron as a bait toxicant and the trophallactic effects between individual members of termite colonies.
2003 - IRG/WP 03-10495
In recent years, because of the favourable environmental characteristics of boron, researchers in the wood preservation industries have refocussed on the use of boron as a major wood preservative against wood-destroying insects. Currently the greatest use of boron compounds is in remedial treatments.
Boron has been found to have slow-acting toxicity against subterranean termites. Because of thi...
B M Ahmed
Toxic value estimation of wood preservatives by using the probit analysis
1990 - IRG/WP 2348
As it was assumed from previous experiments, the probit analysis appears to be the most suitable method of all used to estimate the toxic value of wood preservatives. With the help of the classical agar-block method the probit analysis was tested for its suitability in: 1) fungitoxic value estimation of the WR-3 preservative (quaternary ammonium compound + borate), as compared to different test fu...
J Wazny, K J Krajewski
NIR spectroscopy for rapid estimation of decay resistance
2004 - IRG/WP 04-20294
In Scandinavia Scots pine (Pinus sylvestris L.) is an important commercial tree species. Its heartwood has traditionally been used in constructions exposed to risk of decay. In a laboratory experiment Scots pine wood specimens sampled from inner heartwood, outer heartwood and sapwood were exposed to the brown rot fungus Poria placenta. In general outer heartwood was more resistant than inner heart...
P O Flæte, E Ystrøm Haartveit
Above-Ground Durability Estimation in Australia. Results after 16 years exposure
2005 - IRG/WP 05-20314
A program of research was established in 1987 to examine the above-ground durability of a selection of timbers that are commercially significant in Australia. Test samples were assembled in an L-Joint design and placed on exposure racks in a format to replicate joinery that is exposed to the weather above ground. Both painted and unpainted material has been exposed.
Test samples have been evaluat...
L P Francis, J Norton
Experiences with the OECD guideline proposals for the estimation of emissions from preservative-treated wood in the environment
2004 - IRG/WP 04-50209
The practicability of 2 CEN proposals for OECD guidelines on the estimation of emissions from preservative treated wood by laboratory methods for either wood held in storage after treatment and for wooden commodities that are not covered, and are not in contact with ground (guideline 1) or
wooden commodities that are not covered and are in contact with ground, fresh water or seawater (guideline 2...
U Schoknecht, R Wegner, E Melcher
Detection and estimation of Hylotrupes bajulus L. wood damages by ultrasonics
1990 - IRG/WP 2350
To evaluate the validity of the ultrasonic application in the detection and evaluation of wood damages produced by Hylotrupes bajulus L. larvae, some laboratory tests were made with small wood samples. The pulse through transmission method was used. The transit time of ultrasonic pulses in transversal sections, radial and tangential, of the samples was measured. The increment of the transit time o...
G Prieto
Estimation of mycelial biomass by determination of the ergosterol content of wood decayed by Coniophora puteana and Fomes fomentarius
1989 - IRG/WP 1415
The mycelial biomass of fungi decomposing wood materials may be estimated by the use of an ergosterol assay technique.ln decay tests, essentially according to EN 113, estimates made by HPLC analyses on wood decayed by Coniophora puteana and Fomes fomentarius show the increase in biomass in the wood blocks. The ergosterol contents were correlated with dry weight loss determinations. Degradation of ...
K Nilsson, J Bjurman
Estimation of the impregnation degree of pine wood by the distribution analysis of active ions concentration in the cross-section
1999 - IRG/WP 99-20174
Samples in the form of pine wood rollers of diversified moisture content of ca. 50, 28 and 12% were impregnated with a water solution of the mixture type CCB with the use of the full-cell process. Moisture content was determined in individual layers from the girth to the pith. In the same way the concentrations of copper and chromium ions with the use of the spectrophotometric method and recalcula...
K Lutomski, B Mazela
Determination of fungitoxic value of preservatives in laboratory wood-block tests. Part 2: Statistical estimation
1989 - IRG/WP 2327
Laboratory modified agar-block tests were made to determine the fungitoxic value of the wood preservative CCA against the test fungus Serpula lacrymans using statistical methods. With the aid of statistical computer programmes based on the least square method. the regression equation was found for the dependence between sample mass loss and preservative retention both in terms of percentage and fo...
J Wazny, J D Thornton, K J Krajewski
Comparison of laboratory tests and field experiments for the estimation of emissions from treated wood
2005 - IRG/WP 05-50224-6
The authorisation procedure for biocidal products according to the European Biocides Direc¬tive in¬cludes the assessment of possible environmental risks by the emission of ac¬tive ingre¬dients. This needs an input of data on the expected emissions of biocides into environmental com¬part¬ments. The procedures for the estimation of these emissions should be harmonised. La¬boratory test proceÂ...
U Schoknecht
A review of the current status of the estimation of emissions from preserved wood and their use in the environmental risk assessment of wood preservatives under the Biocidal Products Directive
2005 - IRG/WP 05-50224-7
A review and update of the status of the issues concerning the estimation of emissions from preserved wood (e.g. amendments to the proposed ‘OECD Guidelines’), and the environmental risk assessment of wood preservatives under the Biocidal Products Directive (e.g. compartmental sizes, emissate ecotoxicity testing)....
E F Baines
Estimating the age of subterranean termite attack and damage in buildings
2010 - IRG/WP 10-10727
This paper describes physical and experimental methods and a mathematical model (Rotramel 2003) to assist in estimating the age of subterranean termite attack and damage to building structures. Timber, building and termite management industries have to develop new strategies to assess and estimate termite attack and damage in the current climate of global warming. A case study will be used as an e...
J R J French, B M Ahmed Shiday, J Thorpe
Direct estimation of the durability of high-pressure steam modified wood by ESR-spectroscopy
2010 - IRG/WP 10-40508
Heat generated persistent free radicals have been detected by electron spin resonance measurement of thermally modified wood, prepared by high pressure superheated steam treatment. The specific density of these radicals have been correlated with the durability against basidiomycetes, as measured by the European standard EN113 test. In the lower range of specific radical densities, the found correl...
W Willems, A Tausch, H Militz
Comparison of laboratory and semi-field tests for the estimation of leaching rates from treated wood
2010 - IRG/WP 10-50274
The authorization of wood preservative formulations in the European Union according to the Biocidal Products Directive (BPD) includes the assessment of environmental risks by the emission of active ingredients. This risk assessment includes scenarios for preserved wood (e.g. house scenario, noise barrier), in which the predicted environmental concentration (PEC) for soil and water is calculated, u...
N Morsing, M Klamer, B Seidel, J Wittenzellner, M Maier, J Habicht
Estimation of foraging territories of Microcerotermes diversus Silvestri (Isoptera: Termitidae) in Ahwaz (Iran)
2010 - IRG/WP 10-10744
Microcerotermes diversus Silvestri (Isoptera: Termitidae), an important wood pest in Ahwaz (Khuzestan, Iran), causes serious economic damage to wooden products in buildings. In this study, the foraging territories of this subterranean termite have been determined by mark-release-recapture technique. Estimated foraging territories for colonies A and B were 25.59 and 44.16 m2, respectively. The maxi...
B Habibpour, F Kocheili, M Ekhtelat