Your search resulted in 392 documents. Displaying 25 entries per page.
Chemical, physical and biological factors affecting wood decomposition in forest soils
2003 - IRG/WP 03-20281
Organic matter (OM) decomposition is an important variable in determining the potential of forest soils to sequester atmospheric CO2. Studies using OM from a particular location gives site-specific decomposition information, but differences in OM type and quality make it difficult to compare results among soils and forest ecosystems. By using a “standard” OM in decomposition studies, OM qual...
M Jurgensen, P Laks, D Reed, A Collins, D Page-Dumroese, D Crawford
The dry rot fungus Serpula lacrymans, its growth and damaging of wood
2004 - IRG/WP 04-10511
The dry rot fungus (Serpula lacrymans) is one of the most dangerous wood rotting fungi, especially in the built environment. In our mycological laboratory more experiments with this fungus have been carried out aimed at:- its growth under stable and variable climatic conditions, - its possibility to attack
either natural wood of different species and also modified wood primary pre-treated with ...
L Reinprecht
Preliminary study on relation of wood structure to copper/chrome/arsenic (CCA) distribution in kempas (Koompassia malaccensis)
1995 - IRG/WP 95-40054
Kempas had been treated with copper/chrome/arsenic (CCA) preservative using full cell process. Analysis of preservative distribution at the micro level in relation to wood structure was carried out using scanning electron microscope (SEM) and energy dispersive X-ray (EDXA) analysis. The results showed that CCA elements were detected in all wood tissues at different ratios. Distribution of chemical...
S Ani, S Salamah
Albumin borate: A new non-toxic, wide-spectrum, long-term wood preservative
1998 - IRG/WP 98-30167
Boron, widely recognized for its broad range of activity towards both fungi and insects and for its low mammalian toxicity, can not provide long term protection to treated timber due to its high leachability.
Boron, in the form of boric acid, can be partially fixed to timber by the formation of an association with egg albumin, which is insolubilized by heat-induced coagulation. Chemical investiga...
M-F Thévenon, A Pizzi, J-P Haluk
Wood decay of Pinus sylvestris L. by marine fungi
1990 - IRG/WP 1463
Waterlogged wood decay by marine microorganisms represents a major problem for the conservation of wood structures of historic value. It is important to know which kind of decay affects the wood from a conservation point of view. Enzyme activities of 14 marine fungi belonging to several localities were studied. Also, the weight loss and the rot type suffered by the wood at a microscopic level were...
M C Escorial, M T De Troya, J E Garcia de los Rios
Relationship between bond strength and surface characteristics of CCA-treated Douglas-fir
1993 - IRG/WP 93-30008
Chromated-copper-arsenate (CCA) treated Douglas-fir was laminated using a commercial phenol-resorcinol resin. CCA treatment enhanced the water repelleney of wood espeeially in the presence of extractives. However, the shear strength of CCA treated wood was 12% lower in dry condition and 38% lower in wet condition after six cycles of vacuum-pressure test than that of untreated wood. Slight removal ...
K Yamamoto, J N R Ruddick
Practical consequences of the clarification of the chemical mechanism of CCA fixation to wood
1983 - IRG/WP 3220
Practical consequences derived from the chemical investigation of the mechanism of fixation of CCA to the wood constituents are discussed. Among these, formulas for the calculation of the time of hexavalent chrome fixation are presented. Furthermore, three parameters are shown to be important to the long-term effectiveness of CCA-treated timber: (i) the temperature of treatment, (ii) the initial p...
A Pizzi
Assessment of dehydrogenase activity, fluoride content and total chromium content of soil profiles exposed to preservative treated wood within a model system
1993 - IRG/WP 93-10015
The development and prospective use of a closed model system to facilitate study of a number of indicators of environmental impact of wood preservatives laboratory conditions has been described (IRG/WP/2395-92). Chemical analysis of leachate samples collected from drained soil profiles containing creosoted pole sections remedially treated with a chromated fluoride preservative indicated small incr...
G M Smith, D C R Sinclair, A Bruce, H J Staines
The case for non-chemical termite barriers in termite control
1989 - IRG/WP 1381
A brief outline of current non-chemical barriers in subterranean termite control and their use in Australia is presented. Recent use of non-chemical barriers in Hawaii has led to their evaluation in termite control here and elsewhere. In Australia, preliminary laboratory and field experiments have shown similar results to those found against Coptotermes formosanus in Hawaii, namely, Australian Cop...
J R J French
Evaluation of substituted isothiazolone as a potential new wood preservative
1984 - IRG/WP 3306
Laboratory decay tests were carried out with isothiazolone (4,5-dichloro-2-n-octyl-4-isothiazolone-3-one) treated wood. This compound was found to be extremely effective against three common wood decaying brown-rot fungi, exhibiting toxic threshold values in the range of 0.37 to 0.50 kg/m³. For the white-rot fungus, Coriolus versicolor, the toxic threshold values for treated pine and sweetgum wer...
D D Nicholas, A F Preston, D E Greenley, S V Parikh
A Long-term Observation of Termite Activity in The Nest by Continuous Acoustic Emission (AE) Monitoring
2003 - IRG/WP 03-20280
In order to evaluate the influence of temperature on the termite activity, acoustic emission (AE) monitoring was applied to two nests of Coptotermes formosanus SHIRAKI; a nest in the stem of a standing tree and a nest in the underground of a wooden house, respectively. Temperature change in and around the nests were continuously measured for about one year using thermocouples at four points; the c...
Y Yanase, Y Fujii, S Okumura, T Yoshimura, Y Imamura
Microscopical analysis of formaldehyde-acid modified wood
1981 - IRG/WP 3182
Cross-linking of wood with gaseous formaldehyde improves its hygroscopic and dimensional behaviour, and its resistance against micro-organisms. However, formaldehyde cross-linking reactions take place only in the presence of an acid catalyst, which results in losses in mechanical By optimization of a formaldehyde-sulfur dioxide vapour phase process the reaction conditions were established to limit...
M Stevens, N Parameswaran
Enzyme systems of bacterial isolates from ponded logs - Potentials of pectin and/or starch degradation
2000 - IRG/WP 00-10378
This paper deals with the degradation potentials of wood constituents by the bacterial isolates from ponded logs. The potentials to degrade pectin as a constituent of pit-tori as well as starch existing in ray parenchyma cells in the areas of sap- and transition wood with the isolates were examined. The pectinase activity was investigated by means of the degradation degree of a carrot strip used a...
S Doi, S Ohta
The chemical nature of bis(tributyltin) oxide in Pinus sylvestris sapwood
1989 - IRG/WP 3508
Tributyltin compounds have been used for many years as wood preservatives. This study has provided, for the first time, an explanation for the previously reported dealkylation and/or volatilisation of the tributyltin species in, and from, Scots pine (Pinus sylvestris) sapwood. Thus, 119 Sn nuclear magnetic resonance studies have shown that, on impregnation into this timber, bis(tributyltin) oxide ...
S J Blunden, R Hill
Chemical and biological studies of organotin treated and painted wood stakes after outdoor exposure
1987 - IRG/WP 3419
Organotin based wood preservatives containing tributyltin oxide (TBTO) or tributyltin naphthenate (TBTN) are used in Sweden mainly for double-vacuum treatments of window joinery of Pinus sylvestris. After impregnation the joinery is painted or stained in different colours. To evaluate this effect (different colours on the degree of degradation of TBTO and TBTN, effected by different temperatures i...
M-L Edlund, B Henningsson
Improving the weather resistance of glue-laminated jarrah and karri
1994 - IRG/WP 94-40017
Surface modification and dimensional stabilisation significantly increased the dry and wet shear strength of karri and jarrah lap-shear specimens (laminates) bonded with resorcinol formaldehyde. The combination of surface modification (sanding/sodium hydroxide treatment), and furfurylation produced the highest dry and wet shear strengths. Acetylated laminates had the lowest dry bond strength, but ...
J Balfas, P D Evans
Some data on the activity of alternative fungicides for wood preservation
1985 - IRG/WP 3333
Data from laboratory tests against basidiomycete fungi are presented for 9 alternative fungicides in organic solvent formulations and also in water for one product. Results are compared with data for reference preservatives, tributyltin oxide, copper and zinc naphthenates and pentachlorophenol. Of special interest is the apparently better than additive effect of mixing tributyltin naphthenate and ...
A F Bravery, J K Carey
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 c...
J Jellison, J Connolly, K C Smith, W T Shortle
An evaluation of chemical treatments for the protection of radiata pine logs from fungal degrade
1986 - IRG/WP 3377
Busan 30, Busan 1009, Mitrol PQ375. and sodium pentachlorophenoxide (NaPCP) plus have been evaluated as antisapstain treatments for the long-term protection of debarked radiata pine logs. After 3 months' winter-spring storage, treated debarked logs had less surface and internal sapstain than 'control' logs. After 6 months' storage all logs had internal sapstain ...
J A Drysdale, M E Hedley, J A Butcher
Treatability problems - Relationships between anatomy, chemical composition and treatability
2001 - IRG/WP 01-40213
This report documents the results of phase 1 and 2 of a 3-phase research program. In phase 1, two hundred and fifty-six (256) Southern pine (pinus spp.) nominal 2 x 6's (38 mm x 140 mm) from a single mill in Georgia (southeastern US) were evaluated for treatability with CCA preservative. After treatment, 128 pieces representing a broad range of treatment characteristics were selected and ...
J E Winandy, F Green III, D Keefe
Correlation between changes in colour and chemical composition during photo-degradation of wood surfaces
2005 - IRG/WP 05-40301
Changes in colour of wood (yellowing) during photo degradation or weathering reflect chemical changes in wood. Therefore, the relationship between changes in chemical composition and CIELAB colour parameters is very important to characterize photodegradation of lignocellulosic surfaces. In this study, the changes in chemical composition and yellowing due to photo-degradation was studied by expos...
K K Pandey
A suggestion for the improvement of the chemical protection of wooden poles
1987 - IRG/WP 3445
Insufficient drying of white poles in Sweden causes inadequate penetration of the impregnation compounds, CCA salts and creosote, in a varying proportion of the treated poles, and with pretreatment decay present, sooner or later, internal fungal attack in the ground-line zone of the standing poles is the result. The application of a diffusing fungicide in the ground-line zone in connection with th...
H Friis-Hansen
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 ...
J Bjurman
Properties of hot oil treated wood and the possible chemical reactions between wood and soybean oil during heat treatment
2005 - IRG/WP 05-40304
Thermal treatment with hot oil as the heating media based on the original idea from oil-heat treatment in Germany was investigated. The treatment was mainly carried out at 200ºC and 220ºC for 2 hours and 4 hours, and the wood species were mainly spruce and fir. This paper focuses on the difference between soybean oil and palm oil and the possible chemical reactions between wood and soybean oil. ...
Jieying Wang, P A Cooper
Changes in pore structure and cell wall volume in wood decayed by brown- and white-rot fungi
1991 - IRG/WP 1501
Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (=Poria) placenta or Phanerochaete chrysosporium in soil-block cultures. Decay was terminated at various weight losses, and the pore volumes available to probes of various molecular weight and diameter were determined by the solute exclusion technique (Stone, J.E. and A.M. Scallan. 1968. Cellulose Chem. Technol. 2, 343-358.)....
D S Flournoy