Your search resulted in 26 documents. Displaying 25 entries per page.
Inhibition of wood decay and termite damage by calcium precipitation
1996 - IRG/WP 96-30111
Fungal decay of wood in service, especially brown rot, results in billions of dollars (US) of losses annually. Recent environmental restrictions, both U.S. and international, are limiting or eliminating the use of broad spectrum biocides for wood preservation, primarily due to problems with disposal. In order to design new, environmentally benign methods for control of wood decay fungi, it is esse...
F Green III, T A Kuster, L Ferge, T L Highley
Inhibition of termite damage by N'N-napthaloylhydroxyamine (NHA): Reticulotermes flavipes (Kollar) vs. Coptotermes formosanus Shiraki
2000 - IRG/WP 00-10354
The calcium precipitating agent NHA has been shown to protect southern yellow pine (SYP) from wood decay and termite damage comparable to CCA in field tests (Gulfport, MS) for two years (Crawford and Green, 1999). In a collaborative study, SYP wood blocks were vacuum treated with three concentrations of aqueous NHA and exposed in a no-choice test to Eastern subterranean termites (FPL, USA) and For...
F Green III, S T Lebow, T Yoshimura
Mineralization of European oak with various ionic salt solutions to achieve an in situ precipitation of calcium oxalate
2019 - IRG/WP 19-40861
Thin specimens of European oak (Quercus spp.) with the dimensions of 4 × 20 × 50 mm3 were treated with various aqueous ionic salt solutions of calcium chloride, potassium oxalate and calcium acetate. Additionally, the oak was treated with combinations of calcium chloride and potassium oxalate, as well as calcium acetate and potassium oxalate with the aim to precipitate in situ the water insolubl...
T Franke, T S Volkmer
Wood in concrete. Summary of discussion at IRG 14, Surfers Paradise, Australia
1984 - IRG/WP 3264
The performance of untreated and preservative treated wood when placed in direct contact with concrete was considered in a discussion session at IRG 14. While published reports in this area are scarce, research is in progress internationally and a variety of practices are currently available to minimize any additional hazard posed by contact with concrete. This report summarizes the points raised ...
R J Murphy
Collaborative soft rot tests: Results of analyses of soil samples
1976 - IRG/WP 263
C R Levy
Leachability of borate-modified oriented strandboard: A comparison of zinc and calcium borate
2002 - IRG/WP 02-40232
The leachability of boron in zinc and calcium borate-modified oriented strandboard (OSB) was investigated in this study. The leaching experiments were conducted by exposing edge-sealed OSB samples under running water for 8, 24, 72, and 216 hours. The results were compared with those from the unleached controls. Boron leaching of the modified OSB occurred upon the initial water exposure, and the le...
S Lee, Q Wu
1983 - IRG/WP 3268
The course of fixation of Cu-Cr-As wood preservatives
1972 - IRG/WP 307
Copper-chrome-arsenic (CCA) preservatives in contact with wood result in an instant extensive increase of pH, because of ion-exchange and adsorption reactions with the wood. During precipitation of the active elements the pH continuously increases but reaches a maximum, when all chrome is consumed. Some of the early reaction products are unstable and slowly convert via dissolution into stable comp...
Oxalate production and calcium oxalate accumulation by Gloeophyllum trabeum in buffered cultures
1994 - IRG/WP 94-10075
Most basidiomycetous fungi produce oxalic acid as a result of their metabolic activities and nutrient procurement. There is currently a renewed interest in the role that oxalic acid may play in the decomposition of wood by basidiomycete fungi. It has been observed that although most wood degrading fungi have the capacity to produce oxalic acid, not all of these organisms express this capacity equa...
J H Connolly, J Jellison
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
Decay and mold resistance of borate modified oriented strandboard
2003 - IRG/WP 03-40260
Decay and mold resistance of zinc borate (ZB) and calcium borate (CB) modified oriented strandboard (OSB) from southern mixed hardwoods and yellow pine was investigated in this study. Tests were done with brown rot, Gloeophyllum trabeum, and white-rot, Trametes versicolar, fungi for 8 and 12 weeks, respectively. Wood species and fungus type had significant influence on the decay resistance. Decay...
Q Wu, S Lee, J P Jones
A comparison of the leaching resistance of diammine-copper complexes and copper carbonate precipitated in wood
1997 - IRG/WP 97-30158
Previous studies have shown that during treatment of wood with ammoniacal copper solutions, both simple copper precipitates and diammine-copper complexes are formed. The objective of the present study is to determine the relative importance of both forms of copper, on such aspects as preservative leachability and biological performance. In the current experiment, the leachability of copper carbona...
Xiao Jiang, J N R Ruddick
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 6: The length of the primary precipitation period
1975 - IRG/WP 359
The end of the primary precipitation fixation period of CCA preservatives coincides with the first peak in pH versus time. This offers a simple way of estimating the duration of the period. The duration is determined by a number of factors and their interactions, the most important of which are: wood species (anatomy, natural pH, accessibility of reducing agents), preservative type, preservative c...
Alkaline building materials and controlled moisture conditions as causes for dry rot Serpula lacrymans growing only in houses
1985 - IRG/WP 1272
Dry rot Serpula lacrymans ( Fr.) S.F. Gray is commonly found in houses, though never with certainly in nature, like other wood destroying fungi which grow both indoors and outdoors. In investigating series of dry rot instances it was shown that this fungus is always found in covered places, close to a moisture source, the distance being from 0 a maximum of 600 cm. Owing to the dry rot has been abl...
Old and new facts on the dry rot fungus Serpula lacrymans
1991 - IRG/WP 1470
The article collates some of the recent literature on the biology of the dry rot fungus Serpula lacrymans. The fungus can grow at 28°C, and maximum wood moisture is above 55%. Serpula Iacrymans degrades crystalline cellulose. The intensive production of extracellular oxalic acid is neutralized by calcium and iron. There is considerable variation among the strains with regard to factors such as gr...
O Schmidt, U Moreth-Kebernik
Investigations into the biology of Meruliporia incrassata
2004 - IRG/WP 04-10508
The dry rot fungus Meruliporia incrassata (Berk. and Curt.) Murr. is a highly destructive brown rot wood decay fungus and is a significant pest of wooden structures. The fungus, know commonly as ‘Poria’, is characterized in culture by strand mycelium and skin-like surface mycelium. In structural environments it is found to produce prominent water conducting rhizomorphs, is a copious spore prod...
J Jellison, C Howell, B Goodell, S L Quarles
Production, function and neutralization of oxalic acid produced by the dry rot fungus and other brown rot fungi
1987 - IRG/WP 1330
The formation of oxalic acid by the wood-destroying fungi causing brown rot, is found to be the key which by hydrolysing the hemicellulose brings the cellulose in the tracheid wall in contact with the cellulase enzymes and yeld watersoluble sugars leaving only a lignin skeleton. To control the pH in the substrate the excess oxalic acid is precipitated to water insoluble calcium oxalate by the dry ...
Effect of post-treatment processing on leachability of ACZA-treated douglas-fir lumber
1998 - IRG/WP 98-50109
The effect of post-treatment procedures that more rapidly precipitate copper, zinc, and arsenic in douglas-fir treated with ammoniacal copper zinc arsenate (ACZA) on subsequent leaching resistance were investigated at two retentions (6.4 and 40 kg/m3). Total leaching was greater from boards treated to the higher retention. At both levels, copper was lost at the highest rate. Post-treatment process...
J J Morrell, C S Love, S Kumar, C M Freitag
Serpula lacrymans the dry rot fungus. Revue on previous papers
1989 - IRG/WP 1393
It is found that the Dry rot fungus Serpula lacrymans grows in houses only because of its need for basic materials to neutralize the oxalic acid production or heavy metals which celate the oxalic acid. The average distance from the mycelium to the basic materials is found in average to be 14.2 cm with a variation from 0-100 cm. In contrast to Serpula lacrymans the Coniophora puteana and the Rigido...
The influence of cement and calcium compounds on the performance of CCA preservatives
1983 - IRG/WP 3221
The influence of cement and calcium compounds on the durability of untreated and CCA treated wood is considered. Calcium compounds were found to reduce the toxicity of a CCA preservative to a soft rot fungus at copper to calcium ratios of 1:1 and 1:10 using a cellulose filter paper technique. Further studies are outlined and some possible mechanisms by which cement and calcium compounds may affect...
R J Murphy
Effects of bleaching process on the roughness values of wood surfaces of Lebanon cedar (Cedrus libani A. Rich.) and Black poplar (Populus nigra L.) using NaOH (sodium hydroxide), H2O2 (hydrogen peroxide) and Ca(OH)2 (calcium hydroxide)
2008 - IRG/WP 08-40403
Technical progress in the wood industry has been rapid in recent times. In this case, the quality assurance of the consumer products aligned with aesthetics value appears as one of the most important parameters. Because of the outer appearance of goods exert an effect on customers, interest in production of high quality surfaces of wooden commodities has increased essentially based on the surface ...
I Usta, E Aydinlar
Serpula lacrymans – calcium, iron, and foundering wooden boats
2009 - IRG/WP 09-10691
Serpula lacrymans is one of the most destructive wood-degrading brown rot fungi in temperate environments. Its virulence has often been linked to its ability to grow over non-woody materials and extract calcium (Ca) or iron (Fe) to promote wood degradation in buildings. This fungus has also been a severe problem in historic wooden warships and in modern wooden vessels, sometimes leading to founder...
J S Schilling, S M Duncan
Protein extraction from wood decay fungus Postia placenta
2014 - IRG/WP 14-10827
Wood decay fungi (often distinguished as white rot and brown rot) belonging to the basidiomycetes, are common inhabitants of forest litter, where they play an important role in carbon cycling. Brown rot fungi are perhaps the most important organism involved in the degradation of wood products, and of considerable economic importance. Brown rotted wood loses strength very early because of the rapid...
A Pilgård, P Arnold, K Richter
Study on the Effects of Flame Retardant in Dancheong for Korea Wooden Cultural Heritage
2015 - IRG/WP 15-40692
This study identifies the effect of the agent depending on environment change and conducted basic study to prepare criteria for stable application. Dancheong sample, which is similar to wooden cultural heritage, was manufactured to study the effect of the agent on dancheong. Regular observation on the samples located in inland and shoreline area in the country detected visible phenomena. Whitening...
Hwa Soo Lee, So Jung Lee, Gyu Seong Han, Yong Jae Chung
Green approach in wood mineralization for improvement of fire properties
2022 - IRG/WP 22-30769
Various treatments have been developed in order to improve fire properties of wood. Because the use of some flame retardants can release toxic compounds in the event of a fire, leading to poisoning or even death of people from smoke inhalation, the use of no-toxic and more ecologically acceptable flame retardants is preferable. Mineralization of wood with the incorporation of carbonates has proven...
A Pondelak, R Repič, L Škrlep, N Knez, F Knez, A S Škapin