Your search resulted in 25 documents.
The effect of chitosan on the growth and physiology of two wood inhabiting fungi
2006 - IRG/WP 06-10590
The effect of chitosan on the wood inhabiting fungi Sphaeropsis sapinea and Trichoderma harzianum was evaluated at cellular level. Increasing concentrations of chitosan caused an increase in the amount of peroxide in cultures of S. sapinea, which was accompanied by a simultaneous decrease in superoxide. The same effect was not observed in T. harzianum. The growth of both fungi was inhibited when h...
D Vesentini, T Singh
Oxidative stress and lignin peroxidase production in Phanerochaete chrysosporium
2008 - IRG/WP 08-10655
In Phanerochaete chrysosporium liquid cultures, the induction of lignin peroxidases is directly related to accumulation of reactive oxygen species at the mitochondrial level. In this study, we demonstrate that the expression of the mitochondrial thiol-related antioxidant system is not directly coupled to the LiPs expression. When the antioxidant systems are not able to cope with ROS accumulation, ...
M Morel, L Diss, C Fourrey, M Chalot, M Droux, J P Jacquot, E Gelhaye
Nondestructive Evaluation of Oriented Strand Board Exposed to Decay Fungi
2002 - IRG/WP 02-20243
Stress wave nondestructive evaluation (NDE) technologies are being used in our laboratory to evaluate the performance properties of engineered wood. These techniques have proven useful in the inspection of timber structures to locate internal voids and decayed or deteriorated areas in large timbers. But no information exists concerning NDE and important properties of wood composites exposed to dec...
B Illman, V W Yang, R J Ross, W J Nelson
Improvement of liquid penetration of wood by precompression under appropriate conditions and recovery process
1993 - IRG/WP 93-40014
A new system for enhancing the penetration of liquid into wood using a precompression treatment was designed, and the effects of compressive deformation and recovery on liquid uptake were evaluated. Precompression of up to 60% under appropriate moisture and heat conditions effectively increased the penetration of liquid into refractory wood samples of practical sizes without producing any strength...
I Iida, Y Imamura
Innovations in the treatment of Southern pine heartwood
2000 - IRG/WP 00-40172
Whereas the sapwood of southern yellow pine (Pinus spp.) is readily treatable, the heartwood is essentially impermeable to preservatives such as chromated copper arsenate (CCA). Preliminary studies at the Mississippi Forest Products Laboratory indicate that increases in penetration and retention of preservative in pine heartwood can be obtained by subjecting kiln dried dimension stock to varying m...
M G Sanders, T L Amburgey, H M Barnes
Alternative technologies for wood wastes recycling - Part B: Biotreatment of PCP- and creosote-treated wood
1998 - IRG/WP 98-50101-18 b
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
S Legay, P Marchal, G Labat
Effect of soft-rot decay on the static bending strength of wood
1991 - IRG/WP 2361
In this study, a modified static bending test has been developed as a method for measuring soft-rot decay in soil bed studies. A good correlation was found between the strength loss of the southern pine test specimens and extent of decay. This data suggests that it may be possible to develop a dynamic test based on stress relaxation that is more sensitive than static bending....
D D Nicholas, J A Wilson, R C Vasishth
Respiratory response of the wood boring teredinid, Lyrodus pedicellatus (Quatrefages) to copper stress
2004 - IRG/WP 04-10528
Wood boring teredinid molluscs engulf most of the wooden particles scrapped by them while actively boring into wood, obtaining nourishment for their metabolic activities. In order to protect the wooden structures from the biodeteriorating activity of such organisms, the wood is treated with different chemical formulations to prolong their service life. Copper chrome arsenic (CCA) is one such woo...
V Kuppusamy, M Balaji, M V Rao, K S Rao
Natural progression of decay in unrestrained, Southern pine sapwood exposed above ground
1995 - IRG/WP 95-20060
In this study, the natural progression of decay is being monitored in 2.4-m (8-ft) lengths of dimension lumber. The 2.4-m lengths are supported without restraint in a horizontal plane approximately 0.75 m above ground in a partially shaded field plot in southern Mississippi. The lumber is 100% sapwood. Prior to installation in the field, each piece was planed to exactly 38 by 89 mm² (1.5 by 3.5 i...
R C De Groot, R J Ross, W Nelson
Non-destructive stress wave measurement of decay and termite attack in experimental wood units
1986 - IRG/WP 2256
The purpose of this study was to determine if stress wave analysis could be used to monitor the degradation of wood specimens exposed to the brown-rot decay fungi (Gloeophyllum trabeum) and of wood specimens subjected to attack by subterranean termites. One hundred fifty 3/4 by 3/4 by 12 in. Southern pine specimens were used for exposure to brown-rot decay fungi and two hundred twenty-five 3/4 by ...
R F Pellerin, R C De Groot, G R Esenther
New approaches to practical evaluation method of bio-degradation of wooden construction - Non-destructive detection of defects using radar technique
2000 - IRG/WP 00-20214
There have been a number of researches and developments on the techniques and apparatus for the nondestructive evaluation of the biological deterioration in wood and wooden constructions, such as decay or insect attack in house, public buildings or in historically important architectures. As for the detection of the decay in wood, techniques using sound in audible or in ultrasonic frequency ranges...
Y Fujii, Y Komatsu, Y Yanase, S Okumura, Y Imamura, M Tarumi, H Takiuchi, A Inai
Alternative technologies for wood wastes recycling - Part A: Supercritical extraction of PAH compounds from wood wastes
1998 - IRG/WP 98-50101-18 a
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
L Schrive, C Perre, G Labat
The influence of drying and chemical stress on the lignin degradation in aspen by Phanerochaete chrysosporium
1992 - IRG/WP 92-1573
Wood wafers of Populus tremuloides sapwood were incubated on common media with the white rot fungus Phanaerochaete chrysosporium (wild isolate) and subjected to cyclic drying or chemical agents (low levels of borate or trifluoperazine [a calmodulin antagonist]). After a mass loss of approximately 5.5%, wafers were dried and analyzed for acid-insoluble lignin. Those wafers containing chemical agent...
E L Schmidt, Y-L Lin
Prevention of non-microbial sapwood discolorations in hardwood lumber: chemical and mechanical treatments
1997 - IRG/WP 97-30137
Sapwood discolorations in hardwood lumber that are non-microbial in origin result from the formation of pigmented starch-like granules in ray parenchyma cells. These discolorations can be prevented by treating unseasoned lumber with an antioxidant (sodium bisulfite). Exposing unseasoned lumber to microwaves or treating logs with fumigants also will prevent these discolorations. Subjecting unseason...
T L Amburgey, S Kitchens
Monitoring a Timber Bridge in Norway
2004 - IRG/WP 04-40282
We have instrumented three different timber bridges in Norway for the Norwegian Public Roads Administration. The goal was to learn more about the properties of timber bridges. We have instrumented Evenstad Bridge, Daleråsen Bridge and the last year Flisa Bridge. All bridges are have creosoted glulam trusses and creosoted stress laminated deck. Evenstad and Flisa have an asphalt deck on top, while...
F G Evans
Antifungal activity of plant derived extracts against G. trabeum
2007 - IRG/WP 07-30433
While synthetic chemicals have provided excellent protection to woods used in adverse environments, the general public remains interested in naturally derived wood protectants. There are diverse arrays of possible candidates, but many of these compounds are not readily water soluble and efforts to render them soluble often reduce biological activity. In this report, we describe efforts to enhance ...
M Maoz, I Weitz, M Blumenfeld, C Freitag, J J Morrell
Postia placenta gene expression of oxidative and carbohydrate metabolism related genes during growth in furfurylated wood
2009 - IRG/WP 09-10701
A range of studies the last decade have shown that modified wood can provide excellent protection against a range of wood deteriorating organisms, including decay fungi. However, we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward e.g. inhibition of action of specific enzymes, but they still need testing. An understandi...
G Alfredsen, C G Fossdal
Detection and Assessment Healthy Situation of Poulus Euphratica Oliv. with Stress Wave
2009 - IRG/WP 09-20415
The defects of tree trunk of Poulus euphratica Oliv were inspected by stress wave method and diagnosed with transmission time and velocity. The reference values of transmission time of unit length and velocity from stress wave were used to assess the healthy situation of tree trunk. The goal is provide fast inspecting technology and assessment method for the historic trees in China. The results sh...
Shanqing Liang, Nana Hu, Lanying Lin, Feng Fu
Tensile stress relaxation of wood impregnated in different ACQ formulations at various temperatures
2009 - IRG/WP 09-40456
The reactions between ammoniacal copper quat (ACQ) constituents and wood components were investigated by tensile stress relaxation approach. Small wood samples were stressed and impregnated in ACQ solutions with different formulation including the ethanolamine (MEA) to copper molar ratio, copper (as copper oxide) to quat (as DDAC) weight basis, treatment temperature and also the solution concentra...
Lili Yu, Jinzhen Cao
The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz
Stress wave and visual analysis of treated and non treated fence posts after 15 years in field test
2010 - IRG/WP 10-20449
Wood preservation may play an important role in protecting tropical rain forest. Basically, it can reduce pressure on natural resources by increasing wood durability. Field tests are conducted to simulate final use of woods under different environmental conditions. Visual analysis, non destructive testing, and non destructive evaluation techniques were applied to assess wood resistance and chemica...
A Florian da Costa, R Faustino Teles, J Costa Gonçalves
The effects of acetylation level on the growth of Postia placenta
2011 - IRG/WP 11-10751
To understand the defence mechanisms utilized by decay fungi when exposed to different wood protection systems the study of gene expression can give us some answers. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by differen...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II
The effects of acetylation level on the growth of Postia placenta over 36 weeks
2012 - IRG/WP 12-40589
Genomic sequencing gives us a tool to systematically and rapidly discover novel genes, how their products function in the cell, and explore their interactions. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by different wood...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II
Possible targets of wood modification in brown rot degradation
2014 - IRG/WP 14-40676
Wood modification protects wood from fungal degradation in a non-toxic manner. However, the mechanisms behind the decay resistance in modified wood are currently unknown. The aim of this study was to discuss the i) colonisation, ii) nutrient recognition, iii) transcription, iv) depolymerisation and v) hydrolysis steps in the brown rot degradation progress and explore whether they are inhibited by ...
R Ringman, A Pilgård, G Alfredsen, B Goodell, K Richter
Different levels of acetylation lead to groupwise upregulation of non-enzymatic wood degradation genes of Rhodonia placenta during initial brown-rot decay
2020 - IRG/WP 20-10958
Rhodonia placenta, often used as a model fungus to represent brown rot fungi, uses a two-stepped degradation mechanism to degrade wood. Regarding the overcoming of wood protection systems the initial degradation phase seems to be the crucial point. A new laboratory test enables the separation of the non-enzymatic oxidative and the enzymatic degradation phases, which has previously been proven chal...
M Kölle, R Ringman, A Pilgård