Development of an accelerated soil-contact decay test

Holzforschung ◽  
2007 ◽  
Vol 61 (2) ◽  
pp. 214-218 ◽  
Author(s):  
Gan Li ◽  
Darrel D. Nicholas ◽  
Tor P. Schultz
Keyword(s):  
Test Performance ◽  
Treated Wood ◽  
Wood Decay ◽  
Untreated Wood ◽  
Bending Elasticity ◽  
Decay Test ◽  
Copper Naphthenate ◽  
Copper Depletion ◽  
Copper Arsenate ◽  
Amended Soil

Abstract An accelerated method to evaluate wood preservatives for soil contact was explored using thin (4 mm) pine sticks in small decay cups containing non-sterile soil and wood compost-amended soil. The extent of wood decay was measured by monitoring changes in the bending elasticity (MOE) of the test samples, which was found to be a sensitive measure of the decay extent for both chromated copper arsenate (CCA)- and copper naphthenate (CuNap)-treated wood, and untreated wood. The decay rate was rapid, with significant decay detected in untreated wood after only 2 months of exposure. Decay in both treated and untreated wood samples was observed sooner when the soil was amended with wood compost. The compost-amended soil also gave significantly higher copper depletion for CCA- but not CuNap-treated wood. Although the results from this test should not be extrapolated to predict field test performance, it does appear to be applicable for rapid comparison of the performance of new and established preservative systems.

Differential Expression of a Putative Copper Homeostasis CutC Gene in Fibroporia radiculosa During Initial Decay of Copper-Treated Wood

2020 ◽  
Vol 70 (4) ◽  
pp. 469-475
Author(s):  
Katie M. Ohno ◽  
Amy B. Bishell ◽  
Glen R. Stanosz
Keyword(s):  
Differential Expression ◽  
Treated Wood ◽  
Wood Decay ◽  
Untreated Wood ◽  
Copper Homeostasis ◽  
Southern Pine ◽  
Decay Fungi ◽  
Wood Decay Fungi ◽  
Decay Test ◽  
Pinus Spp

Abstract Living organisms require copper for several cellular processes. Yet intracellular concentrations of copper must be regulated to avoid toxicity. Not much is known about mechanisms of copper regulation in wood decay fungi. However, one putative annotation for a copper homeostasis CutC gene (FIBRA_00129), found in other brown-rot wood decay fungi, has been annotated in Fibroporia radiculosa. The aim of this study was to evaluate wood mass loss and differential expression of FIBRA_00129 during initial decay of untreated and copper-treated wood by two copper-tolerant F. radiculosa isolates (FP-90848-T and L-9414-SP) compared with copper-sensitive Gloeophyllum trabeum. Untreated southern pine (Pinus spp.) and ammoniacal copper citrate treated southern pine at three concentrations (0.6%, 1.2%, and 2.4%) were used in a 4-week-long standard decay test. Results showed G. trabeum was unable to decay copper-treated wood while both F. radiculosa isolates successfully decayed southern pine at all copper concentrations. G. trabeum and F. radiculosa L-9414-SP showed no detectable FIBRA_00129 expression over the course of this study. F. radiculosa FP-90848-T showed greater FIBRA_00129 downregulation on copper-treated wood than on untreated wood (P = 0.003). Additionally, there was greater FIBRA_00129 downregulation in F. radiculosa FP-90848-T at week 3 compared with other weeks (P = 0.015). Future studies are needed to further evaluate FIBRA_00129 during the decay process to determine its potential role in copper-tolerance.

scholarly journals Dimensional stability, fungal resistance and mechanical properties of radiata pine after combined thermo-mechanical compression and oil heat-treatment

Holzforschung ◽  
2016 ◽  
Vol 70 (8) ◽  
pp. 793-800 ◽  
Author(s):  
Manoj Kumar Dubey ◽  
Shusheng Pang ◽  
Shakti Chauhan ◽  
John Walker
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Dimensional Stability ◽  
Linseed Oil ◽  
Treated Wood ◽  
Untreated Wood ◽  
Radiata Pine ◽  
Fungal Resistance ◽  
Compression Set ◽  
Decay Test

Abstract The dimensional stability and mechanical properties of radiata pine (Pinus radiata) has been investigated after thermo-mechanically compression (TMC) followed by oil heat-treatment (OHT). Wood specimens were first compressed in the radial direction then heat-treated in a linseed oil bath at 160–210°C. Spring-back percentage, water repellence efficiencies, and compression set recovery percentage were determined as indicators of dimensional stability. The resistance of treated wood against a brown rot fungi was assessed based on an accelerated laboratory fungal decay test. Strength, stiffness and hardness were determined as a function of different treatment parameters. After TMC, high compression set (39%) was achieved without any surface checks and cracks. Specimens undergoing TMC followed by OHT showed relatively less swelling and low compression set recovery under high moisture conditions. The fungal resistance of wood after TMC+OHT slightly increased compared to untreated wood and TMC wood. The mechanical properties of TMC+OHT wood were inferior to those of TMC wood.

scholarly journals Gene Expression Analysis of Three Putative Copper-Transporting ATPases in Copper-Tolerant Fibroporia radiculosa

2020 ◽  
Vol 11 ◽  
Author(s):  
Katie M. Ohno ◽  
Amy B. Bishell ◽  
Glen R. Stanosz
Keyword(s):  
Treated Wood ◽  
Untreated Wood ◽  
Brown Rot ◽  
Wood Products ◽  
Copper Tolerance ◽  
Decay Fungi ◽  
Putative Gene ◽  
Gene Annotations ◽  
Decay Test ◽  
Copper Tolerant

Copper tolerance of brown-rot basidiomycete decay fungi can lessen the efficacy of copper-containing wood preservatives for wood products in-service. The purpose of this study was to evaluate wood mass loss and differential expression of three genes that have putative annotations for copper-transporting ATPase pumps (FIBRA_00974, FIBRA_04716, and FIBRA_01430). Untreated southern pine (SP) and SP treated with three concentrations of ammoniacal copper citrate (CC, 0.6, 1.2, and 2.4%) were exposed to two copper-tolerant Fibroporia radiculosa isolates (FP-90848-T and L-9414-SP) and copper-sensitive Gloeophyllum trabeum isolate (MAD 617) in a 4-week-long standard decay test (AWPA E10-19). Decay of copper-treated wood was inhibited by G. trabeum (p = 0.001); however, there was no inhibition of decay with increasing copper concentrations by both F. radiculosa isolates. Initially, G. trabeum and one F. radiculosa isolate (L-9414-SP) highly upregulated FIBRA_00974 and FIBRA_04716 on copper-treated wood at week 1 (p = 0.005), but subsequent expression was either not detected or was similar to expression on untreated wood (p = 0.471). The other F. radiculosa isolate (FP-90848-T) downregulated FIBRA_00974 (p = 0.301) and FIBRA_04716 (p = 0.004) on copper-treated wood. FIBRA_01430 expression by G. trabeum was not detected, but was upregulated by both F. radiculosa FP-90848-T (p = 0.481) and L-9414-SP (p = 0.392). Results from this study suggest that all three test fungi utilized different mechanisms when decaying copper-treated wood. Additionally, results from this study do not provide support for the involvement of these putative gene annotations for copper-transporting ATPase pumps in the mechanism of copper-tolerance.

scholarly journals Air permeability and sound absorption coefficient changes from ultrasonic treatment in a cross section of Malas (Homalium foetidum)

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Chun-Won Kang ◽  
Eun-Suk Jang ◽  
Nam-Ho Lee ◽  
Sang-Sik Jang ◽  
Min Lee
Keyword(s):  
Absorption Coefficient ◽  
Ultrasonic Treatment ◽  
Sound Absorption ◽  
Gas Permeability ◽  
Treated Wood ◽  
Untreated Wood ◽  
Sound Absorption Coefficient ◽  
Permeability Constant ◽  
Average Value ◽  
Permeability Increase

AbstractWe investigated the effect of ultrasonic treatment on Malas (Homalium foetidum) gas permeability and sound absorption coefficient using the transfer function method. Results showed a longitudinal average Darcy permeability constant of 2.02 (standard deviation SD 0.72) for untreated wood and 6.15 (SD 3.07) for ultrasound-treated wood, a permeability increase of 3.04 times. We also determined the average sound absorption coefficients in the range of 50 to 6.4 kHz and NRC (noise reduction coefficient: average value of sound absorption coefficient value at 250, 500, 1000, and 2000 Hz) of untreated Malas. Those values were 0.23 (SD 0.02) and 0.13 (SD 0.01), respectively, while those of ultrasonic-treated Malas were 0.28 (SD 0.02) and 0.14 (SD 0.02), a 19.74% increase in average sound absorption coefficient.

Growth behavior of wood-destroying fungi in chemically modified wood: wood degradation and translocation of nitrogen compounds

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Lukas Emmerich ◽  
Maja Bleckmann ◽  
Sarah Strohbusch ◽  
Christian Brischke ◽  
Susanne Bollmus ◽  
...  
Keyword(s):  
Protective Action ◽  
Treated Wood ◽  
Untreated Wood ◽  
Brown Rot ◽  
Decay Resistance ◽  
White Rot ◽  
Decay Fungi ◽  
Chemically Modified ◽  
Decay Tests ◽  
Modified Wood

Abstract Chemical wood modification has been used to modify wood and improve its decay resistance. However, the mode of protective action is still not fully understood. Occasionally, outdoor products made from chemically modified timber (CMT) show internal decay while their outer shell remains intact. Hence, it was hypothesized that wood decay fungi may grow through CMT without losing their capability to degrade non-modified wood. This study aimed at developing a laboratory test set-up to investigate (1) whether decay fungi grow through CMT and (2) retain their ability to degrade non-modified wood. Acetylated and 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) treated wood were used in decay tests with modified ‘mantle specimens’ and untreated ‘core dowels’. It became evident that white rot (Trametes versicolor), brown rot (Coniophora puteana) and soft rot fungi can grow through CMT without losing their ability to degrade untreated wood. Consequently, full volume impregnation of wood with the modifying agent is required to achieve complete protection of wooden products. In decay tests with DMDHEU treated specimens, significant amounts of apparently non-fixated DMDHEU were translocated from modified mantle specimens to untreated wood cores. A diffusion-driven transport of nitrogen and DMDHEU seemed to be responsible for mass translocation during decay testing.

Laccase-catalyzed functionalization with 4-hydroxy-3-methoxybenzylurea significantly improves internal bond of particle boards

Holzforschung ◽  
2008 ◽  
Vol 62 (2) ◽  
pp. 223-229 ◽  
Author(s):  
Karin Fackler ◽  
Thomas Kuncinger ◽  
Thomas Ters ◽  
Ewald Srebotnik
Keyword(s):  
Internal Bond ◽  
Treatment Time ◽  
Urea Formaldehyde ◽  
Treated Wood ◽  
Untreated Wood ◽  
Strength Properties ◽  
Positive Interactions ◽  
Formaldehyde Resin ◽  
Significant Difference ◽  
Wood Particles

Abstract Enzymatic functionalization is an attractive tool to provide a reactive interface for further processing of lignocellulosic materials, such as wood particles and fibers. Here, spruce wood particles have been functionalized by fungal laccase combined with 4-hydroxy-3-methoxy-benzylamine (HMBA) or 4-hydroxy-3-methoxybenzylurea (HMBU). The expectation was crosslinking with resins in subsequent glueing processes, which should improve strength properties of particle boards. Essential process parameters, such as liquid to solid mass ratio and treatment time, were optimized on a laboratory scale resulting in HMBA and HMBU binding yields of 90% and above as determined by radiochemical mass balance analysis. We employed a multifactorial experimental design for board production from treated wood particles and urea/formaldehyde resin. Mechanical testing and multivariate data analysis revealed, for the first time, an increase of internal bond (IB) as a result of functionalization with HMBU. HMBA was not successful. Variance analysis of relevant parameters and their interactions demonstrated a highly significant difference (P>99.99%) between boards treated with laccase/HMBU versus untreated wood particles. Due to positive interactions, functionalization was most effective at high bulk density (750 kg m-3) and high resin content (10%) resulting in a calculated IB improvement of 0.12 N m-2 (21%).

scholarly journals Application of Waterborne Acrylic and Solvent-Borne Polyester Coatings on Plasma-Treated Fir (Abies alba M.) Wood

Materials ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 370
Author(s):  
Hadi Gholamiyan ◽  
Behnam Gholampoor ◽  
Reza Hosseinpourpia
Keyword(s):  
Plasma Treatment ◽  
Treated Wood ◽  
Abies Alba ◽  
Untreated Wood ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Accelerated Weathering ◽  
Water Contact ◽  
Before And After ◽  
Carbon Dioxide Co2

This research investigates the effect of plasma treatment with air, nitrogen (N2), and carbon dioxide (CO2) gases on the performance of waterborne (acrylic) and solvent-borne (polyester) coated fir (Abies alba M.) wood samples. The properties of the plasma-coated samples were analyzed before and after exposure to accelerated weathering and compared with those of untreated and solely treated ones. According to pull-off testing, the coating adhesion of the wood samples was considerably improved by plasma treatment, and obvious differences were observed between different plasma gases. The effect was more pronounced after the weathering test. Similar results were obtained for the abrasion resistance of the samples. The water contact angle measurement illustrated more hydrophilic character in the solely plasma-treated wood in comparison with the untreated wood. The application of coatings, however, strongly improved its hydrophobic character. The performances of waterborne and solvent-borne coatings on plasma-treated wood were comparable, although slightly better values were obtained by the waterborne system. Our results exhibit the positive effect of plasma treatment on coating performances and the increased weather resistance of the waterborne and solvent-borne coating systems on plasma-treated wood.

scholarly journals MARINE EXPOSURE TESTS OF COCONUT TIMBER

CORD ◽  
1987 ◽  
Vol 3 (01) ◽  
pp. 34
Author(s):  
R. N. Palomar
Keyword(s):  
Sea Water ◽  
Coal Tar ◽  
Untreated Wood ◽  
Double Diffusion ◽  
Marine Structures ◽  
Sodium Dichromate ◽  
Diffusion Treatment ◽  
Pressure Method ◽  
Copper Arsenate ◽  
Hard Samples

Marine exposure tests of sawn coconut lumber were carried out for three years to determine the resistance, of treated coconut timber to marine borers.   The test panels measuzing 50 mm x 100 mm x 450 mm, were installed in sea water between October, 1981 and September, 1984. Results showed three promising treatments. These were the vacuum/pressure method using chromated copper arsenate, the modifted double diffusion treatment employing mixture of copper adphate, sodium dichromate and arsenic pentoxide, and the hot and cold bath treatment with coal tar creosote. The specimens treated by these preservative systems showed trace or slight sur­face infestation while the untreated wood panels indicated from deep and extensive infestation to failure due to attack of marine borers.   The perfomance of the treated medium density specimens appeared to be inferior than the hard samples indicating that only the latter materials should be used for marine structures.

scholarly journals COLOR CHANGE — MASS LOSS CORRELATION FOR HEAT-TREATED WOOD

2014 ◽  
Vol 2 ◽  
pp. 345-352 ◽  
Author(s):  
Cristina Marinela Olarescu ◽  
Mihaela Campean
Keyword(s):  
Heat Treatment ◽  
Mass Loss ◽  
Color Change ◽  
Treated Wood ◽  
Untreated Wood ◽  
Cost Effective ◽  
Assessment Procedure ◽  
Mathematical Correlation ◽  
Heat Treated ◽  
Two Parameters

Heat treatment is renowned as the most environmentally friendly process of dimensional stabilization that can be applied to wood, in order to make it suitable for outdoor uses. It also darkens wood color and improves wood durability. The intensity of heat treatment can be appreciated by means of two parameters: the color change occured in wood due to the high temperature, and the mass loss, which is a measure of the degree of thermal degradation. In order to find a mathematical correlation between these two parameters, an experimental study was conducted with four European wood species, which were heat-treated at 180°C and 200ºC, for 1-3 hours, under atmosheric pressure.The paper presents the results concerning the color changes and mass losses recorded for the heat-treated wood samples compared to untreated wood.  For all four species, the dependency between the color change and the mass loss was found to be best described by a logarithmic regression equation with R2 of 0.93 to 0.99 for the soft species (spruce, pine and lime), and R2 of 0.77 for beech. The results of this study envisage to simplify the assessment procedure of the heat treatment efficiency, by only measuring the color – a feature that is both convenient and cost-effective. 

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