Your search resulted in 38 documents. Displaying 25 entries per page.
Preliminary investigation of biological resistance, water absorption and swelling of thermally compressed pine wood panels
2008 - IRG/WP 08-40396
Wood can be modified by compressive, thermal and chemical treatments. Compression of wood under thermal conditions is resulted in densification of wood. This study evaluated decay and termite resistance of thermally compressed pine wood panels at either 5 or 7 MPa and at either 120 or 150?C for one hour. The process caused increases in density and decreases in thickness of the panels; however, lab...
Ö Ünsal, S N Kartal, Z Candan, R Arango, C A Clausen, F Green III
Thermochemical Remediation of Preservative-Treated Wood
2008 - IRG/WP 08-50254
Remediation methods continue to be developed and refined for CCA-treated wood in order to divert this material from landfills and create secondary products from the wood fiber. A two-step thermochemical remediation method was developed to assess the efficiency of metal removal from CCA-treated spruce flakes. Nearly all the metals (As, Cr, and Cu) were thermochemically extracted from chromated copp...
R Sabo, C A Clausen, J E Winandy
Multifactorial Antimicrobial Wood Protectants
2008 - IRG/WP 08-30484
It is unlikely that a single antimicrobial compound, whether synthetic or natural, will provide the ‘magic bullet’ for eliminating multiple biological agents affecting wood products. Development of synergistic combinations of selected compounds, especially those derived from natural sources, is recognized as a promising approach to improved wood protection. Recent adoption of effective fungici...
R D Coleman, C A Clausen
Antifungal Essential Oil Metabolites
2010 - IRG/WP 10-30531
New environmentally-friendly wood protection systems based on “green” technologies are needed to inhibit wood-inhabiting mold and decay fungi. Utilizing bioactive essential oils from select herbaceous plants is one promising approach, but the concentrations of bioactive compounds are somewhat variable even in the highest (therapeutic) grade essential oils. Purified primary metabolites from fou...
C A Clausen, B M Woodward, V W Yang
Above Ground Field Evaluation and GC-MS Analysis of Naturally Durable Wood Species
2012 - IRG/WP 12-10764
Nine wood species are being evaluated in above ground field studies in Mississippi and Wisconsin. Candidate naturally durable wood (NDW) species are being rated at yearly intervals for resistance to decay, cupping, and checking. Field ratings after 12 months exposure are presented. To date, Paulownia tomentosa (PAW) and southern yellow pine (SYP) are least durable and cedars are the most durable i...
G T Kirker, A B Blodgett, S T Lebow, C A Clausen
Transferable Durability: Enhancing decay resistance of non-durable species with extractives from durable wood species
2013 - IRG/WP 13-10808
Extractive content and composition is a vital component of naturally durable woods; however, variability in extractives can limit their usefulness in the field. Two extractive-free, non-durable wood species were pressure treated with ethanol-toluene extractives from 8 durable wood species. Extracted Southern pine, Paulownia and unextracted Southern pine blocks were treated and challenged in soil b...
G T Kirker, A B Blodgett, S Lebow, C A Clausen
Image analysis for mould and sapstain detection on wood
2013 - IRG/WP 13-20519
Laboratory tests for mould growth on wood products are time consuming and rely on visual assessments of specimens utilizing subjective rating systems. Accelerated laboratory methods are needed that can provide rapid, quantitative assessment of mould and sapstain growth on solid and composite wood products. Image analysis of scanned spore imprints from southern pine or oriented strandboard (OSB) sp...
C A Clausen, V W Yang
Removal of nano- and micronized-copper from treated wood by chelating agents
2013 - IRG/WP 13-50294
Micronized and nano-copper (Cu)-based and arsenic and chromium-free systems have received much attention for wood protection in recent years. Because they have different fixation, and micro-distribution properties, such copper systems may be more or less subject to release using known remediation methods than soluble forms of Cu. This study evaluated Cu recovery from wood treated with micronized- ...
S N Kartal, E Terzi, B Woodward, C A Clausen, S T Lebow
The effects of copper proximity on oxalate production in Fibroporia radiculosa
2014 - IRG/WP 14-10823
Copper remains a key component used in wood preservatives available today. However, the observed tolerance of several critical wood rotting organisms continues to be problematic. Tolerance to copper has been linked to the production and accumulation of oxalate, which precipitates copper into insoluble copper-oxalate crystals, thus inactivating copper ions. The purpose of this study was to assess d...
K M Jenkins, C A Clausen, F Green III
Durability and Wood Protection for Historic Covered Bridges in the United States
2014 - IRG/WP 14-10829
A majority of the covered wooden bridges in United States were built in the mid -1800’s. These structures represent a unique cultural and technological heritage from that era. Over time, these bridges have been deteriorated by microorganisms and insects or damaged by acts of vandalism and arson. The National Historic Covered Bridge Preservation (NHCBP) Program sponsored by the Federal Highway Ad...
V W Yang, C A Clausen
Laboratory investigation of fire protection coatings for creosote-treated timber railroad bridges
2014 - IRG/WP 14-30639
As the incidence of timber railroad bridge fires increases, so has the need to develop protective measures to reduce the risk from accidental ignitions primarily caused by hot metal objects. Of the six barrier treatments evaluated in the laboratory for their ability to protect timbers from fires sourced with ignition from hot metal objects only one intumescent coating provided adequate fire prote...
C A Clausen, R H White, J P Wacker, S T Lebow, M A Dietenberger, S L Zelinka, N M Stark
The copper-transporting ATPase pump and its potential role in copper-tolerance
2016 - IRG/WP 16-10859
Copper-tolerant brown-rot decay fungi exploit intricate mechanisms to neutralize the efficacy of copper-containing preservative formulations. The production and accumulation of oxalate is the most widely recognized theory regarding the mechanism of copper-tolerance in these fungi. The role of oxalate, however, may be only one part of a series of necessary components required for this complex mecha...
K M Ohno, C A Clausen, F Green III, G Stanosz
Untreated and copper-treated wood soaked in sodium oxalate: Effects of decay by copper-tolerant and copper-sensitive fungi
2017 - IRG/WP 17-10888
Copper is widely used as the primary component in wood protectants because it demonstrates a broad range of biocidal properties. However, a key concern with using copper in wood preservative formulations is the possibility for brown-rot basidiomycetes to resist the toxic effect. Many brown-rot basidiomycetes have evolved mechanisms, like the production and accumulation of oxalate, which helps thes...
K M Ohno, G T Kirker, A B Bishell, C A Clausen