Your search resulted in 2903 documents. Displaying 25 entries per page.
Determination of the preventive efficacy against wood destroying basidiomycetes fungi, EN V 839 - CEN/TC 38 WG 9
1993 - IRG/WP 93-20015
The WG 9 of CEN TC/38 has presented to EC a mycological test to assess efficacy of preservatives applied by surface process. This method is now an experimental standard (EN V 839) which has to be approved by the different european delegations. The following paper is not the standard as it has been proposed but is a presentation of the principle of the method. The experimental standard specifies a laboratory method of test which gives a basis of the assessment of the preventive action of a wood preservative when applied as a surface treatment against Basidiomycetes fungi. This method is applicable to formulations of preservatives in a ready to use form (organic formulations, organic water-dispersible formulations, water-soluble materials). Series of susceptible wood species specimens are treated on longitudinal faces whith the preservative in test using brushing as surface procedure. Test specimens are then exposed by an intermediate mesh to feeder blocks infestedby pure culture of Basidiomycetes fungi in sterile conditions and penetration of fungi is assessed on cross section sawn in the samples at the end of the test.
Determination of toxic limits of wood preservatives towards wood-destroying Basidiomycetes. Investigation on the effect of the use of two impregnated wood blocks and of one impregnated and an untreated block respectively in Kolle jars on the toxic limits of wood preservatives
1973 - IRG/WP 225
Determination of physical properties of wood by Novel Guide
2006 - IRG/WP 06-40345
In empirical and theoretical determination of physical properties of wood, a schematic guide has been developed (as a novel guide) for the purpose of bringing facilities to researchers with a processing quantity in terms of data compilation. In this article physical properties of wood have been briefly described in respect to their effect on impregnation process, and technical information has been provided on usage of novel guide.
I Usta, M D Hale
Laboratory determination of the natural decay resistance of some lesser-utilized timbers from Tanzania against wood decay fungi
2004 - IRG/WP 04-10517
Four lesser known/utilized timber species (sap and heartwoods) from Tanzania, namely Albizia lebbeck, Zanthoxylum gilletii, Faurea saligna and Parinari curatellifolia were exposed to the brown rot fungi (Gloeophyllum trabeum and Coniophora puteana) and the white rot fungus (Coriolus versicolor) to determine their natural decay resistance according to the EN 113 standard procedure. The timbers were also ranked into natural durability classes according to EN 350-1. Albizia lebbeck, Faurea saligna and Parinari curatellifolia timber species (heartwood) were found to be very resistant while Zanthoxylum gilletii was heavily decayed by all the fungi. The durability ratings of the timbers were; Albizia lebbeck (1), Faurea saligna (1), Parinari curatellifolia (1) and Zanthoxylum gillettii (5). It is suggested that the durable timbers, Albizia lebbeck, Faurea saligna and Parinari curatellifolia should be promoted as alternatives to the well known durable timber species in Tanzania such as Tectona grandis, Afzelia quanzensis, Blachylaena hutchinsii and Pterocarpus angolensis which are currently being over-exploited.
P R Gillah, R C Ishengoma, E Julias, S A Amartey, D H Kitojo
Determination of total fluoride in preservative-treated wood by ion selective electrode, without steam distillation
1996 - IRG/WP 96-20086
An analytical method was developed to determine total fluoride in wood treated with aqueous fluoride or borate-fluoride formulations. Ground wood was mixed with 60% sodium hydroxide solution and oven-dried overnight before furnacing at 600°C. The cool fused product was dissolved in warm water before adding a powerful complexant/buffer solution containing sulphosalicylic acid and EDTA. Fluoride was measured by ion-selective electrode (ISE) against appropriately matrix-matched calibration standards containing 1, 10, or 100 ppm F. The method compared favourably with two alternatives; one employed the time-consuming distillation step included in the AWPA A2 1994 method, with a titration finish, and the second employed a double fusion and ISE finish, using TISAB buffer. The chosen buffer system exhibited better capacity than TISAB to complex excesses of model interferant Al. B and Si were also accommodated. Recovery from spiked Eucalyptus maculata (at 0.05-0.5% m/m F) was 94-96%. Precision when analysing Alstonia scholaris containing 0.35% m/m F was about 2%. The method enables better throughput than the AWPA A2 94 method
M J Kennedy
The reliability of colouring methods for the determination of biflourides and boron in spruce wood
1994 - IRG/WP 94-20036
From practical reasons, qualitative spraying methods are widely used for the detection of bifluorides and boron in wood. The main aim of this research was to detect whether the concentration of the active ingredient in the coloured area is equal or greater than the toxic value against basidiomycetes. Both colouring methods, Z-A reagent for fluorides and curcuma reagent for boric acid, are a reliable means for the determination of the toxic threshold value, (found in literature) against basidiomycetes in spruce wood. Quantitatively, for fluorides the Eriochromocyaninezirkoniumoxidchloride method (DIN 52161 part 4) and for boron the mannitol - azomethine method (Peylo, 1993; Merck, 1989) are easy to perform and accurate
R Grell, M G Sanders, W J Homan, H Militz
Determination of fixation properties by bioassays - A proposal for the assessment of safety indexes in wood protection
1990 - IRG/WP 3566
In the determination of environmental effects of chemicals tests with fishes, daphnia and algae have proved to be practicable. With respect to wood protection such bioassays are suitable to control effects of treated timber against aquatic organisms. By using the fish-acute-toxicity-test the development of a laboratory test method is described for the checking of the fixation rate of a copper-chromium wood preservative. By this the importance of the observation of a proper fixation period is demonstrated for the use of treated wood in water contact. Estimating ecotoxicological effects of leachable compounds using sensitive bioindicators allows a differentiated determination of environmental risks of impregnated timber. The comparison with the toxic effects of the compounds of a wood preservative are a first step in the assessment of safety indexes in wood protection.
A comparison of inductively coupled plasma spectroscopy and neutron activity analysis for the determination of concentrations in wood
1993 - IRG/WP 93-10048
As wood decays the ionic composition changes, with increases often being seen in the concentrations of Ca, Mg, Fe, Mn and sometimes K. The concentration of eight cations in red spruce sapwood and heartwood samples was determined independently by inductively coupled plasma spectroscopy (ICP) and by neutron activation analysis (NAA) as part of an effort to standardize our analytical procedures and create a uniform wood standard for use by multiple researchers. Preliminary studies indicate a difference in the values of Ca and K as estimated by ICP and NAA, possibly due to a loss of these elements due to volatilization during ashing.
J Jellison, J Connolly, K C Smith, W T Shortle
ATP assay for the determination of mould activity on wood at different moisture conditions
1992 - IRG/WP 92-2397
To determine fungal responses to fungicides and environmental conditions and for detection of microbial activity in wood, sensitive and objective methods are needed. We have developed a suitable assay based on analysis of adenosine triphosphate (ATP) by using the luciferin-luciferase reaction. With the aid of this assay the activity of Penicillium brevicompactum on wood at different RH levels was studied. The ATP content in a two week old culture responded quite rapidly to changes in humidity. The ATP content in the colony moved to 70% or lower RH for one week was 10 times lower than the ATP content in the colony kept at 100% relative humidity for the same time period. Increasing the humidity level to 100% RH one week before the ATP determination from a period at lower humidities did not result in a significant increase in the ATP content. This probably indicates that the mycelia of the fungus did not survive the low humidity treatment.
Longterm monitoring of termite activity on multiple feeding sites: a laboratory method intended for the determination of attractant/repellent properties of wood preservatives and baits
2001 - IRG/WP 01-20225
A method is introduced allowing the continuous monitoring of the activity of a small laboratory termite- colony at 8 different feeding sites simultaneously. The test assembly consists of a small central polycarbonate-tube containing a colonie of Reticulitermes santonensis (de Feytaud) beeing connected with 8 external feeding sites by small glass-capillaries. The termites passing through the glass capillaries to and from the feeding sites are interrupting an infrared light-barrier. Each signal from the light-barriers is conditioned and fed to a PC-based signal-recognition-, monitoring- and storage-system. First results show that a colony of 500 individuals of Reticulitermes santonensis (de Feytaud) will need approx. 2 to 3 weeks for establishing a new, full functional hierarchy. A well established Reticulitermes- colony will show 80 to 100 passings per minute to and from the eight feeding sites. The activity of Reticulitermes santonensis (de Feytaud) shows no circadian activity rhythmic.
M Pallaske, E Graf, H Takiuchi
Determination of total fluoride and boron in preservative-treated wood fluoride by ion selective electrode without steam distillation, and boron colorimetrically using azornethine-h
1998 - IRG/WP 98-20135
An analytical method was developed to determine total fluoride and boron in wood treated with aqueous or solid diffusing fluoride or borate-fluoride formulations. Ground wood was mixed with 30% sodium hydroxide solution and oven-dried for 2 hours before furnacing at 600° C for 1 hour. The cool fused product was dissolved in hot water, transferred to a plastic beaker and neutralised. Fluoride was measured by ion-selective electrode (ISE), after adding Ionic Strength Adjustment Buffers (ISAB), against appropriately pH and matrix-matched calibration standards containing 1, 3, 5, 10 and 50 ppm F. Boron was determined colorimetrically on the same neutralised solution using azomethine-H chemistry. Citric acid, sulphuric acid and nitric acid were evaluated as neutralising agents. While the choice of neutralising acid had no significant influence on the determination of boron by azomethine-H, speed and stability of the ISE for fluoride was best with nitric acid at 3.75M. The ISABs Sulphosalicylic acid and EDTA (SSA-EDTA); tri-sodium citrate and potassium nitrate; tiron and sodium nitrate; and TISAB were all evaluated for fluoride determination. Only SSA-EDTA was found to complex aluminium adequately, also accommodating borate, silicate and iron. Although SSA-EDTA has been traditionally used at pH 9.5 for the determination of fluoride in large amounts of aluminium, we found that use at this pH led to significant problems from hydroxide ion interference, slow electrode response, and pH changes due to loss of ammonia, all resulting in poor detection limits and reproducibility. To improve method performance, the pH of standards and samples was adjusted to 8.7, and all samples were spiked with an additional 1 mg/L fluoride. Interference from aluminium increased marginally, but the SSA-EDTA buffer was still capable of masking aluminium at a ratio of 20:1 AI:F, when measuring solutions containing 5 mg(F)/L. The method compared favourably with two alternatives; one employed the time-consuming distillation step included in the AWPA A2-1994 method, with a titration finish, and the second employed a double fusion and ISE finish, using TISAB buffer. Mean recovery from spiked Tasmanian oak (Eucalyptus regnans) at 0.05% - 0.20% m/m B/F was 95-105%. Precision at 0.2% m/m B/F in wood was about 3% for F and 1% for B. Detection limits of 30 mg/Kg for F and 20 mg/Kg for B were adequate for monitoring movement of toxicants within remedially-treated hardwood poles.
P A Collins, M J Kennedy
Determination of absorption, accumulation and transport of copper in mycelium of some wood decay fungi
1999 - IRG/WP 99-10323
Copper compounds are common wood preservatives. However, tolerance of some wood decay fungi to copper compounds has been observed recently. Therefore, we tried to elucidate possible causes of this phenomenon. We investigated uptake, accumulation and secretion of copper in the mycelium of potentially copper tolerant fungi (Antrodia sp.) and non tolerant fungus Trametes versicolor. We observed that potentially tolerant fungi have lower uptake of copper to the mycelium than non tolerant species. They also do not transport copper into the medium. That means that copper tolerance of fungi is probably based on low uptake of copper to the mycelium and not on the active transport from the mycelium to the medium.
F Pohleven, S Breznikar, P Kalan, M Petric
Gas chromatographic determination of 1,8-naphthalimide, N-Hydroxy-1,8-naphthalimide (N,N-naphthaloylhydroxylamine) and the sodium salt of N-Hydroxy-1,8-naphthalimide
2003 - IRG/WP 03-20259
A number of naphthalimide (NI) derivatives are used as efficient laser dyes, in medicine or in scanning electron microscopy. Only N,N-naphthaloylhydroxylamine (NHA) has been shown to be an effective wood preservative against wood decay fungi and termite damage. However, limited information is available concerning the analytical detection of NI-derivatives in treated timber. There is a clear need for the analytical characterisation; e.g. with regard to the penetration depth or the assessment of retention after leaching. This paper describes the development of a gas chromatographic method for determination of NI and their derivatives in timber. These investigations were carried out by means of direct thermal desorption-gas chromatography-mass spectrometry (TD-GS-MS) using the pure substances in solution, as well as direct analysis of treated southern yellow pine (SYP). It was shown that the identification of NHA in treated SYP is possible using this analytical technique. Furthermore first evidence is given for determining quantitative data. Surprisingly, the chromatograms and especially mass spectra obtained for NHA and the sodium salt of NHA are identical to the mass spectra of NI. The first results show that TD-GC-MS can be an option in determining the retention levels of NI and their derivatives in wood.
E Melcher, F Green III
Determination of ethanolamine in impregnated wood
2000 - IRG/WP 00-20198
Leaching of copper based preservatives from wood is usually prevented by adding chromium compounds to copper containing formulations. It seems that suitable substitutes for chromium fixation agents may be amines. In this paper, we report our results on interactions between copper(II) octanoate and ethanolamine (C2H7NO, 2-aminoethanole) with wood or its components. A part of ethanolamine from a wood preservative chemically reacts with wood and does not evaporate from it. This can be seen from retentions and from the changes of FTIR spectra of treated wood. We assume that ethanolamine mainly reacts with hemicelluloses and lignin complex. The unevaporated part of ethanolamine is even higher (for 2%) in the presence of copper(II) octanoate. We think that this difference originates from ethanolamine, which is complexed to copper(II) octanoate. Ethanolamine in wood can be easily determined with the indicator bromphenol blue in ethanol/acetic acid aqueous solution. Wood with ethanolamine turns blue while wood without ethanolamine remains yellow.
M Humar, M Petric
Determination procedure for wood preservatives in waste wood - statistics of sampling and analysis
1998 - IRG/WP 98-50121
In a RTD research programme funded by the German Federal Environmental Agency (UBA - Report No. 126-06-010103) a standardised and validated procedure was developed for sampling and analysing wood preservative components in waste wood. For this investigation a realistic quantity of waste wood from house demolition was used and 80 components analysed. The examination of single wood pieces and woodchips prepared therefore showed a good correlation with the retention of wood preservatives. For the estimation of the potential contamination of inhomogenic waste wood samples we developed a concentration-level model. There are three concentration-levels: Level 1: with preservative concentrations corresponding to waste of untreated - 'naturelike' - wood; level II: with concentrations higher than 'naturelike' wood and level Ill: with treated wood, under consideration of washout- and evaporation processes. For As, B, Cd, Cr, Cu, F, Hg, Pb, Sn, Zn, PAH (EPA), PCP, TCP and Lindane values were determined as known from naturelike waste wood. For calculating 90 percentile values a statistical method was used called "bootstrap" (n = 25). These values are interesting in context with the German waste law ("Kreislaufwirtschafts- und Abfallgesetz"), which prohibits the waste dilution and waste mixing. This demand causes specific problems in the production of chipboards when waste wood is used. The results indicate that the methods used for sampling and analysis can be applied for a safe and reproducible identification of wood preservatives in single wood pieces and shreddered wood chips.
P Stolz, J Krooss, U Thurmarm, R-D Peek, H Giese
Application of (n-a)-radiography for determination of boron in wood impregnated with boron-containing antispetics
1975 - IRG/WP 351
The method of (n-a)-radiography for quantitative determination of boron is based on creation of defective regions (tracks) in a polymer (the detector), which form during passage of a particles through the detector, these particles being produced in the reaction 10B(n, a)7Li when the test specimen in contact with the detector is irradiated with neutrons. Etching of the detector with an appropriate reagent after irradiation reveals defective regions, permitting optical recording of the tracks and subsequent calculation of the concentration of boron in the specimen. Determination of boron inclusions using cellulose acetate was effected in Nb3Al and V3Si, and in glasses. It has been shown that quantitative determination of boron and its spatial distribution in austentic steels is possible with the aid of cellulose acetate and nitrate. The spatial distribution of boron in minerals and rocks has been investigated using cellulose nitrate. In the present work we investigated the possibility of employing (n-a)-radiography for quantitative determination of boron in wood impregnated with boron-containing antiseptics. One of the most important features characterizing the application of this method to wood is that mineralization of the specimens is unnecessary. The specimens analyzed were specimens of birch and aspen, impregnated with BBK-2 solution. The nitro base of AM-1 cine film was employed as the track detector.
N A Dubinskaya, M Ya Tsel'millere
The influence of the location of a wood defect on the modulus of elasticity determination in wood durability testing
2004 - IRG/WP 04-20287
This study investigates the influence of the location of a wood failure in stakes upon elastic changes observed in beech specimens with the resonance vibration technique. Natural failures were simulated by artificially created defects at different locations of the test stake. The results indicate that the location of an attack in a stake is important for the measurement outcome. When the attack is located at far ends of a stake, the detected faults are underestimated. Higher losses of modulus of elasticity were recorded with notches in comparison to bore hole defects. The non-destructive vibration approach (dynamic MOE) applied in durability testing offers advantages compared to conventional static techniques.
L Machek, H Militz
A novel guide for the determination of the physical properties of wood including kiln drying and full-cell preservative treatment
2004 - IRG/WP 04-20298
An ideal flow chart for the sequential experimental determination of a range of physical properties relevant to wood drying and subsequent preservation was designed as a novel guide to assist wood scientists. In this manner, data assembly and experimental processing are shown. This was designed according to experience and published literature. Aspects emphasised in this review were the physical properties which effect the manner of processing particularly in respect to preservative treatment of wood. For this purpose a total of 93 references covering 8 topics (descriptive wood anatomy, physical properties of wood, shrinkage and swelling, wood density, moisture content, fibre saturation point, wood drying (by oven and kiln) and liquid permeability) were reviewed.
I Usta, M D C Hale
A comparison between different accelerated test methods for the determination of the natural durability of wood
1996 - IRG/WP 96-20099
According to the European standard EN 350-1 the natural durability of wood is defined as: "the inherent resistance of wood to attack by wood destroying organisms". This standard also describes how, for certain hazard classes, the durability is determined. The two methods described in this standard are the kolleflask method (EN 113) and the field-stake-test method (EN 252). The EN 113 test gives results within a short period of time by using isolated fungi cultures. A good prediction from the test results to the natural durability of timber in use is a problem. In contrary, the test results of EN 252 in outdoor field tests show the durability of timber species under certain soil and climate conditions, but the test takes a long period of time (years to decades) before an evaluation can be done. In different countries in Western-Europe a discussion is going on about the use of tropical hardwoods and timber from fast growing plantages. The impact of this is that there is a growing need for alternative timbers, which can substitute well known durable species. Quite often the durability of the alternative species is not well known. To give a reasonable prediction of the durability of wood species within a short period of time, a reproducible, reliable and fast test method for predicting durability is needed. Previous research on this subject (Polman et al. 1992) showed that with the aid of an accelerated stake-test, useful results can be achieved. The research described here was done to develop such a method. For this reason, results from an accelerated soil bed test were compared with EN 113 fungal tests and a modified field-test EN 252. For a further comparison, softrot tests following the standard ENV 807 were performed.
H Militz, S G L Michon, J E Polman, M Stevens
Determination of chlorine-containing wood preservatives in art objects using Micro-XRF
2003 - IRG/WP 03-20266
The applicability of a mobile energy-dispersive micro X-ray fluorescence (μ-XRF) spectro-meter for the analysis of organochlorine-containing wood preservatives in art objects was tested. Information about the relative degree of contamination and the efficacy of detoxification measures with emulsive solvent systems can be gained using the intensity of the chlorine signals. μ-XRF technique combines the advantages of a high spatial resolution, as needed in studies of penetration profiles and transport processes of cut sections and the possibility to analyze larger areas in a relatively short time. The method allows a non-destructive determination of the degree of surface decontamination after cleaning treatments.
J Bartoll, A Unger, S Krug, K Püschner, H Bronk
The quantitative determination of quaternary ammonium compounds in treated timber – results of an extended ring test
2002 - IRG/WP 02-20240
The determination of quaternary ammonium compounds (QAC) by means of a 2-phase-titration or photometry is a well established procedure for the quantification of cationic detergents in aqueous solutions. It is known that this analytical principle can also be used for the measurement of QAC extracted from treated timber. However only few information are available concerning the reproducibility or the recovery rate of this procedure. In order to validate the whole technique an extended ring test was performed by 8 participants. Impregnated milled spruce with a QAC content of 1000mg/kg was distributed between the partners in a first stage. In a second step milled spruce with an “unknown” lower concentration (220mg/kg) and finally impregnated EN 113 test specimens (3-4kg QAC/m³) were investigated. The sample preparation, the extraction of QAC as well as the quantitative determination were performed according to standard or “in house” procedures. The analytical procedures were used successfully for the quantification of QAC in treated timber ranging from 200 to 1000mg/kg. Furthermore it could be shown that in general the recovery rate varies between ± 5% independent of the analytical method used whereby a higher deviation was found for material with a low QAC content. It was also to be seen that the extraction procedure is by far the most important factor of the analysis.
E Melcher, C Bornkessel, J Gunschera, R Hamberg, H Härtner, H-N Marx, U Schoknecht, J Wittenzellner
Determination of N-cyclohexyl-diazeniumdioxide (HDO) containing compounds in treated wood using GC-MS
2000 - IRG/WP 00-20201
Beside the biological effectiveness the approval of a chemical wood preservative requires also techniques for the analytical determination of active ingredients in different matrices. Fulfilling of the last requirement is particularly difficult in the case of impregnated timber treated with wood preservatives containing organic compounds. This paper describes a procedure for the determination of the organic ingredient N-cyclohexyl- diazeniumdioxide (HDO) in solid phases using gas chromatography coupled with mass spectrometry (GC-MS) in connection with a previous thermal desorption step. For this powdered samples are placed in a glass tube. Then the tube is reinserted into the thermal desorption unit which is placed in the GC-oven and directly connected with the capillary column. Afterwards the sample was quickly heated up to 200°C. The resulting gas mixture is pushed onto the column and the separation of the gas components took place. The single components could be identified by means of the retention time and the mass spectrum. A quantitative determination seems to be possible by means of the intensity of the signals. The suitability and reproducibility of this method of the determination of HDO were tested successfully by analysing a number of impregnated wood specimens treated with different formulations containing HDO.
P Jüngel, J Wittenzellner, E Melcher
Determination of boron levels in solution and in treated wood
1994 - IRG/WP 94-20041
Four methods of measuring boron levels in solutions were investigated. The methods compared included the azomethine-H method which is commonly used in soils and plant tissues, the methods outlined in the Australian Standard AS 1605 (1974) and in Wilson (1958), and the atomic absorption spectrophotometry method. Defect-free radiata pine (Pinus radiata D. Don) sapwood and wood flakes were treated to different percentage boric acid equivalent (%BAE). A slightly acidic aqueous medium was used to extract boron from the samples. Extracts were analysed using the azomethine-H and carmine methods. The recovery and coefficient of variation were calculated and discussed. Results confirmed that all methods can be used for measuring boron in solution and wood samples at the range of%BAE investigated. However, the azomethine-H method was found not only to be the simplest and quickest but the most accurate method. It was also found that wood extractives in the wood did not affect the results.
F J Romero, P Vinden, P Kho
Determination methods of phytotoxic effect of wood preservatives
1990 - IRG/WP 2349
The phytotoxic effect of wood preservatives so widely used plays a considerable role in the protection of natural environment. A review was made of the existing methods with which to assess the phytotoxicity of the above chemicals and some suggestions were given concerning the methods most appropriate for their unification. Two areas of research are proposed: 1) estimating the direct effect on indicator plants (white mustard - Sinapis alba, being the obligatory plant, and some other plant depending on the purpose the preservative is used for), 2) estimating the effect of wood treated with a tested preservative, on the some plants. The initial results of phytotoxicity presented here were obtained for the WR-3 preservative (quaternary ammonium compound + borate) B (sodium benzoate + borate) and NaPCP when white mustard and Scotch pine seedlings were used as indicator plants.
A Kundzewicz, J Wazny
Microwave digestion of preserved wood for the determination of Cu, Cr, As, B and P in quality control
1991 - IRG/WP 2364
A microwave digestion method for the determination of copper, chromium, arsenic, boron and phosphorus in preserved woods is described. Samples were digested with nitric acid in pressure-relief type teflon PFA vessels by microwave heating in a commercial laboratory microwave oven. Fast, efficient and complete digestion was achieved within 29 min for 12 samples. The digestion time compared favourably with the 2 h required for conventional procedures. Furthermore the consumption of reagents was reduced significantly. The resulting solutions were analysed by inductively coupled plasma atomic emission spectrometry, but the solutions are also suitable for atomic absorption spectrometry.
N Bernth, L B Sheard