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Carol A. Clausen - One of the best experts on this subject based on the ideXlab platform.
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the role of extractives in naturally durable wood species
International Biodeterioration & Biodegradation, 2013Co-Authors: Grant T Kirker, Rachel A. Arango, A B Blodgett, Patricia K Lebow, Carol A. ClausenAbstract:Abstract There are numerous examples of wood species that naturally exhibit enhanced performance and longevity in outside exposure independent of preservative treatment. Wood extractives are largely considered to be the contributing factor when evaluating and predicting the performance of a naturally durable wood species. However, little test methodology exists that focuses on the extent of the role of extractives in wood durability. In this study, eight candidate naturally durable wood species plus a non-durable control were evaluated in laboratory Soil Block tests for resistance to termite attack and decay by three brown-rot and three white-rot decay fungi. Chemically extracted test Blocks were compared to unextracted controls. Extracted durable species were also compared to non-durable controls. Results showed nearly all of the wood species exhibited higher weight loss due to termite or fungi when extractives were removed and extracted samples had weight losses that were comparable to the non-durable controls.
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Preliminary evaluation of storax and its constituents: Fungal decay mold and termite resistance
International Biodeterioration & Biodegradation, 2012Co-Authors: S. Nami Kartal, Carol A. Clausen, Evren Terzi, Tsuyoshi Yoshimura, Rachel A. Arango, Frederick GreenAbstract:Abstract Essential oils and their derivatives might be one of the promising preserving agents to prevent fungal decay and termite/insect attack in wood since such compounds have a long history of safe usage as antimicrobial agents in various industries. Considerable research has focused on utilizing bioactive essential oils and wood extractives based on green technologies to develop environmentally friendly wood preservatives. This study evaluated biological activities of storax from Liquidambar orientalis tree, some storax constituents and commercial styrax against wood-decaying fungi, mold fungi, and termites in laboratory conditions. Scots pine sapwood specimens were treated with various concentrations of styrax, storax and storax constituents i.e. cinnamyl acetate, cinnamyl alcohol and ethyl cinnamate. Treated specimens were subjected to leaching followed by Soil Block decay tests using two brown rot and two white rot fungi. Specimens were also subjected to two different laboratory termite resistance tests based on the standards methods by the American Society for Testing and Materials (ASTM) and Japanese Industrial Standards (JIS). Inhibitory effects of the compounds were evaluated in vitro against Basidiomycetes, mold, and staining fungi. Treated wood specimens were also tested for mold growth. The storax constituents, storax and styrax did not inhibit fungal decay by the brown rot fungi. The constituents and storax-treated specimens resulted in mostly “moderate resistance” to fungal decay by the white rot fungi based on the ASTM D2017 classification. Styrax only was effective against the Basidiomycetes fungi in vitro tests; however, the mold and staining fungi tested were not completely inhibited. Natural storax at the concentration level of 0.5% inhibited all fungi except Trametes versicolor and Ceratocystis pilifera. Cinnamyl alcohol inhibited fungal growth with the exception of Aspergillus niger. In mold tests, complete inhibition was not observed for any of the test fungi; however, cinnamyl alcohol reduced mold growth considerably on treated wood specimens. Cinnamyl alcohol was also effective against termites in unleached specimens; however, styrax and natural storax at the concentration level of 10% reduced wood consumption in treated specimens.
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protecting wood from mould decay and termites with multi component biocide systems
International Biodeterioration & Biodegradation, 2007Co-Authors: Carol A. Clausen, Vina W YangAbstract:Abstract Biocides must be developed for controlling mould establishment on cellulose-based building materials. Accordingly, biocides intended for indoor applications must be non-toxic, non-volatile, odourless, hypoallergenic, and able to provide long-term protection under conditions of high humidity. Multi-component biocide systems were tested in American Wood-Preservers’ Association Soil Block tests for inhibition of brown-rot and white-rot decay fungi and American Society for Testing and Materials standard tests for inhibition of mould fungi and termites. Multi-component systems combining a borate base supplemented with either 0.1% azole or 0.5% thujaplicin, performed well against the two brown-rot fungi Postia placenta and Gloeophyllum trabeum ; the white-rot fungus Coriolus versicolor ; the three mould fungi Aspergillus niger , Penicillium chrysogenum , and Trichoderma viride ; and the subterranean termite Reticulitermes flavipes (Kollar). It was concluded that for interior applications borate-based multi-component biocide systems can protect wood from decay fungi, mould fungi, and termites, and that a system containing thiabendazole provided protection at a lower retention than the other biocides in this study. Synergy was observed between the borate base and voriconazole in inhibition of mould.
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the effect of cacl2 on growth rate wood decay and oxalic acid accumulation in serpula lacrymans and related brown rot fungi
Holzforschung, 2006Co-Authors: Anne Christine Steenkjær Hastrup, Carol A. Clausen, Bo Boye Busk Jensen, Frederick GreenAbstract:The dry rot fungus, Serpula lacrymans, is one of the most destructive copper-tolerant fungi causing timber decay in buildings in temperate regions. Calcium and oxalic acid have been shown to play important roles in the mechanism of wood decay. The effect of calcium on growth and decay was evaluated for 12 strains of S. lacrymans and compared to five brown-rot fungi. This was done by treating copper citrate (CC)-treated Southern yellow pine (SYP) wood with a CaCl2 solution and estimating the decay rate and amount of soluble oxalic acid in an ASTM Soil Block test. Decay by S. lacrymans was found to be significantly inhibited by treatment with CaCl2 in the presence of copper. In addition, calcium showed no effect on two strains of S. lacrymans and one Serpula himantioides strain in non-copper-treated SYP wood Blocks. The growth rate of S. lacrymans was not affected on malt extract agar containing CaCl2. In summary, a marked decrease was observed in the decay capacity of S. lacrymans in pine treated with CCqCaCl2. The amount of soluble oxalic acid was measured in CC-treated Blocks and Blocks also treated with CaCl2. Of the comparative brown-rot fungi, both Antrodia vaillantii (TFFH 294) and Postia placenta (Mad 698) displayed notable wood decay despite CaCl2 treatment, while the remaining strains were inhibited.
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Copper tolerance of brown-rot fungi : Oxalic acid production in southern pine treated with arsenic-free preservatives
International Biodeterioration & Biodegradation, 2005Co-Authors: Frederick Green, Carol A. ClausenAbstract:The voluntary withdrawal of chromated copper arsenate (CCA)-treated wood from most residential applications has increased the use of non-arsenical copper-based organic wood preservatives. Because the arsenic component of CCA controlled coppertolerant fungi, scientists have renewed interest in and concern about the decay capacity in the important copper-tolerant group of brown-rot fungi. We have demonstrated that the primary means of inactivating copper in preservatives is by excess production of oxalic acid (OA). Oxalic acid production is a key metabolic indicator of brown-rot decay, and our objective was to estimate the production of OA in five commercial or experimental arsenic-free preservatives. Ten aggressive brown-rot fungi, chosen from previous studies and representing the genera Antrodia, Coniophora, Gloeophyllum, Postia, Serpula, Tyromyces, and Wolfiporia, were tested against southern yellow pine (SYP) Blocks that were vacuum-treated with ground contact retentions of copper naphthenate, amine copper azole, alkaline copper quat type D (ACQ-D), N,N -naphthaloylhydroxylamine (NHA), and copper borate in a 12week Soil-Block test. After determination of Block weight loss, Blocks were also tested for the presence of OA. Weight loss ranged from 0.3% to 8.3% for treated Blocks and from 16.4% to 59.6% for untreated controls. We conclude that SYP treated with these five preservatives limited OA production and prevented decay, and thus confirmed the efficacy of the co-biocides against coppertolerant fungi. © 2005 Elsevier Ltd. All rights reserved.
Frederick Green - One of the best experts on this subject based on the ideXlab platform.
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Preliminary evaluation of storax and its constituents: Fungal decay mold and termite resistance
International Biodeterioration & Biodegradation, 2012Co-Authors: S. Nami Kartal, Carol A. Clausen, Evren Terzi, Tsuyoshi Yoshimura, Rachel A. Arango, Frederick GreenAbstract:Abstract Essential oils and their derivatives might be one of the promising preserving agents to prevent fungal decay and termite/insect attack in wood since such compounds have a long history of safe usage as antimicrobial agents in various industries. Considerable research has focused on utilizing bioactive essential oils and wood extractives based on green technologies to develop environmentally friendly wood preservatives. This study evaluated biological activities of storax from Liquidambar orientalis tree, some storax constituents and commercial styrax against wood-decaying fungi, mold fungi, and termites in laboratory conditions. Scots pine sapwood specimens were treated with various concentrations of styrax, storax and storax constituents i.e. cinnamyl acetate, cinnamyl alcohol and ethyl cinnamate. Treated specimens were subjected to leaching followed by Soil Block decay tests using two brown rot and two white rot fungi. Specimens were also subjected to two different laboratory termite resistance tests based on the standards methods by the American Society for Testing and Materials (ASTM) and Japanese Industrial Standards (JIS). Inhibitory effects of the compounds were evaluated in vitro against Basidiomycetes, mold, and staining fungi. Treated wood specimens were also tested for mold growth. The storax constituents, storax and styrax did not inhibit fungal decay by the brown rot fungi. The constituents and storax-treated specimens resulted in mostly “moderate resistance” to fungal decay by the white rot fungi based on the ASTM D2017 classification. Styrax only was effective against the Basidiomycetes fungi in vitro tests; however, the mold and staining fungi tested were not completely inhibited. Natural storax at the concentration level of 0.5% inhibited all fungi except Trametes versicolor and Ceratocystis pilifera. Cinnamyl alcohol inhibited fungal growth with the exception of Aspergillus niger. In mold tests, complete inhibition was not observed for any of the test fungi; however, cinnamyl alcohol reduced mold growth considerably on treated wood specimens. Cinnamyl alcohol was also effective against termites in unleached specimens; however, styrax and natural storax at the concentration level of 10% reduced wood consumption in treated specimens.
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the effect of cacl2 on growth rate wood decay and oxalic acid accumulation in serpula lacrymans and related brown rot fungi
Holzforschung, 2006Co-Authors: Anne Christine Steenkjær Hastrup, Carol A. Clausen, Bo Boye Busk Jensen, Frederick GreenAbstract:The dry rot fungus, Serpula lacrymans, is one of the most destructive copper-tolerant fungi causing timber decay in buildings in temperate regions. Calcium and oxalic acid have been shown to play important roles in the mechanism of wood decay. The effect of calcium on growth and decay was evaluated for 12 strains of S. lacrymans and compared to five brown-rot fungi. This was done by treating copper citrate (CC)-treated Southern yellow pine (SYP) wood with a CaCl2 solution and estimating the decay rate and amount of soluble oxalic acid in an ASTM Soil Block test. Decay by S. lacrymans was found to be significantly inhibited by treatment with CaCl2 in the presence of copper. In addition, calcium showed no effect on two strains of S. lacrymans and one Serpula himantioides strain in non-copper-treated SYP wood Blocks. The growth rate of S. lacrymans was not affected on malt extract agar containing CaCl2. In summary, a marked decrease was observed in the decay capacity of S. lacrymans in pine treated with CCqCaCl2. The amount of soluble oxalic acid was measured in CC-treated Blocks and Blocks also treated with CaCl2. Of the comparative brown-rot fungi, both Antrodia vaillantii (TFFH 294) and Postia placenta (Mad 698) displayed notable wood decay despite CaCl2 treatment, while the remaining strains were inhibited.
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Copper tolerance of brown-rot fungi : Oxalic acid production in southern pine treated with arsenic-free preservatives
International Biodeterioration & Biodegradation, 2005Co-Authors: Frederick Green, Carol A. ClausenAbstract:The voluntary withdrawal of chromated copper arsenate (CCA)-treated wood from most residential applications has increased the use of non-arsenical copper-based organic wood preservatives. Because the arsenic component of CCA controlled coppertolerant fungi, scientists have renewed interest in and concern about the decay capacity in the important copper-tolerant group of brown-rot fungi. We have demonstrated that the primary means of inactivating copper in preservatives is by excess production of oxalic acid (OA). Oxalic acid production is a key metabolic indicator of brown-rot decay, and our objective was to estimate the production of OA in five commercial or experimental arsenic-free preservatives. Ten aggressive brown-rot fungi, chosen from previous studies and representing the genera Antrodia, Coniophora, Gloeophyllum, Postia, Serpula, Tyromyces, and Wolfiporia, were tested against southern yellow pine (SYP) Blocks that were vacuum-treated with ground contact retentions of copper naphthenate, amine copper azole, alkaline copper quat type D (ACQ-D), N,N -naphthaloylhydroxylamine (NHA), and copper borate in a 12week Soil-Block test. After determination of Block weight loss, Blocks were also tested for the presence of OA. Weight loss ranged from 0.3% to 8.3% for treated Blocks and from 16.4% to 59.6% for untreated controls. We conclude that SYP treated with these five preservatives limited OA production and prevented decay, and thus confirmed the efficacy of the co-biocides against coppertolerant fungi. © 2005 Elsevier Ltd. All rights reserved.
Marcos Alexandre Teixeira - One of the best experts on this subject based on the ideXlab platform.
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Desenvolvimento de equipamento para extração de amostras indeformadas de solo
2014Co-Authors: Marcos Alexandre TeixeiraAbstract:Resumo: Desenvolveu-se um equipamento capaz de coletar amostras indeformadas de solo com 70 mm de diâmetro a até 600 mm de profundidade, visando facilitar a obtenção deste tipo de amostras. O amostrador é constituído por um tubo de PVC com 75 mm de diâmetro interno, que recebe a amostra, acondicionado dentro de um tubo cravador, estrutural, de alumínio, com 78,5 mm de diâmetro interno, equipado com uma ponteira de aço SAE 1045 com 69 mm de diâmetro interno, conicidade interna de 1% e altura de 44,3 mm, formando um conjunto sem movimento rotativo. Envolvendo este conjunto há uma rosca-sem-fim, responsável pela cravação do amostrador, com diâmetro externo de 140 mm, equipada com três lâminas de corte na sua extremidade e rotacionada por um motor hidráulico, O conjunto é montado solidário a um mecanismo articulado, responsável pelo movimento vertical do amostrador, acionado por um cilindro hidráulico. O amostrador foi adaptado a um veículo especificamente projetado para o tráfego no campo (VAS - Veículo Amostrador de Solo). Durante o processo de avaliação, a variável analisada foi a velocidade angular da rosca-sem-fim. O critério para verificar alterações na amostra se deu através de: inspeção visual, umidade, densidade global (métodos do anel volumétrico e da parafina), ensaio de compressão triaxial rápido e ensaio de adensamento. Como testemunha, usou-se amostra de solo colhida pelo método do bloco da parafina. As amostras obtidas com a utilização do VAS em solo argiloso (Latossolo Roxo) apresentaram os valores de densidade global (com 95% de confiabilidade estatística), características de resistência à compressão (ensaio triaxial) e adensamento iguais à testemunha. O equipamento mostrou-se adequado para o fim que foi projetado, mostrando-se prático e versátil. O conjunto veículo-amostrador pode ser facilmente posicionado, com uso de GPS, o que o torna bastante útil na coleta de dados para mapeamento de solos e no próprio processo de obtenção de amostras de modo mais eficiente.Abstract: A Soil sampler was designed and constructed to take samples with 0,07 m diameter up to 0,6 m depth in order to obtain undisturbed core samples. The sampler consists mainly of four parts; a removable polyvinyl chloride (PVC) standard sewage pipe with a 0,0712 m inside diameter to receive the Soil,; an aluminum encasing sleeve, with a 0.0785 m inside diameter; an auger made of mild steel, with a 0,140 m outside diameter; and a conic cutting end Machinned from a SAE 1045 steel, similar to the common available coring tubes with a 0,0692 m inside diameter and a clearance angle of 2%, and 0,0443 m long. The rotational movement of the auger was provide by a timing belt transmission, driven by a hydraulic motor, with a torque 32.4 N.m (at 689 kPa) and volumetric displacement of 96,7 cm3/rev. The hydraulic oil for the motor was supplied by a gear pump, with a volumetric displacement of 6,6 cm3/ver driven by a 12 CV four stroke engine with an operation speed of 3600 rpm. The vertical movement of the sampler is guaranteed by a four arm linkage, moved by a hydraulic cylinder. The total vertical displacement of the sampler is 0,80 m. The downward speed is controlled by a flow valve. Since the cutting chisel and coring ring are in the same plane with only 0,005 m difference in diameter, as opposed to the techniques where the casing is forced into the Soil by hydraulic cylinder, only very low pressure must be applied in order to force the cylinder into the Soil, with this drilling technique. The Soil sampler was adapted to a specially designed off road vehicle capable of traveling on adverse field conditions. The quality of the VAS samples were compared with undisturbed samples taken from a Soil Block using laboratory tests. The tests conducted were the triaxial undrained compression test and consolidation test. The results demonstrated that the Soil sampler proposed is capable to take undisturbed Soil samples of clay Soil up to 0,6 m with the same quality of the traditional Soil Block, witch is much more time consuming
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Desenvolvimento de equipamento para extração de amostras indeformadas de solo
Universidade Estadual de Campinas. Faculdade de Engenharia Agricola, 1998Co-Authors: Marcos Alexandre TeixeiraAbstract:Desenvolveu-se um equipamento capaz de coletar amostras indeformadas de solo com 70 mm de diâmetro a até 600 mm de profundidade, visando facilitar a obtenção deste tipo de amostras. O amostrador é constituído por um tubo de PVC com 75 mm de diâmetro interno, que recebe a amostra, acondicionado dentro de um tubo cravador, estrutural, de alumínio, com 78,5 mm de diâmetro interno, equipado com uma ponteira de aço SAE 1045 com 69 mm de diâmetro interno, conicidade interna de 1% e altura de 44,3 mm, formando um conjunto sem movimento rotativo. Envolvendo este conjunto há uma rosca-sem-fim, responsável pela cravação do amostrador, com diâmetro externo de 140 mm, equipada com três lâminas de corte na sua extremidade e rotacionada por um motor hidráulico, O conjunto é montado solidário a um mecanismo articulado, responsável pelo movimento vertical do amostrador, acionado por um cilindro hidráulico. O amostrador foi adaptado a um veículo especificamente projetado para o tráfego no campo (VAS - Veículo Amostrador de Solo). Durante o processo de avaliação, a variável analisada foi a velocidade angular da rosca-sem-fim. O critério para verificar alterações na amostra se deu através de: inspeção visual, umidade, densidade global (métodos do anel volumétrico e da parafina), ensaio de compressão triaxial rápido e ensaio de adensamento. Como testemunha, usou-se amostra de solo colhida pelo método do bloco da parafina. As amostras obtidas com a utilização do VAS em solo argiloso (Latossolo Roxo) apresentaram os valores de densidade global (com 95% de confiabilidade estatística), características de resistência à compressão (ensaio triaxial) e adensamento iguais à testemunha. O equipamento mostrou-se adequado para o fim que foi projetado, mostrando-se prático e versátil. O conjunto veículo-amostrador pode ser facilmente posicionado, com uso de GPS, o que o torna bastante útil na coleta de dados para mapeamento de solos e no próprio processo de obtenção de amostras de modo mais eficiente.A Soil sampler was designed and constructed to take samples with 0,07 m diameter up to 0,6 m depth in order to obtain undisturbed core samples. The sampler consists mainly of four parts; a removable polyvinyl chloride (PVC) standard sewage pipe with a 0,0712 m inside diameter to receive the Soil,; an aluminum encasing sleeve, with a 0.0785 m inside diameter; an auger made of mild steel, with a 0,140 m outside diameter; and a conic cutting end Machinned from a SAE 1045 steel, similar to the common available coring tubes with a 0,0692 m inside diameter and a clearance angle of 2%, and 0,0443 m long. The rotational movement of the auger was provide by a timing belt transmission, driven by a hydraulic motor, with a torque 32.4 N.m (at 689 kPa) and volumetric displacement of 96,7 cm3/rev. The hydraulic oil for the motor was supplied by a gear pump, with a volumetric displacement of 6,6 cm3/ver driven by a 12 CV four stroke engine with an operation speed of 3600 rpm. The vertical movement of the sampler is guaranteed by a four arm linkage, moved by a hydraulic cylinder. The total vertical displacement of the sampler is 0,80 m. The downward speed is controlled by a flow valve. Since the cutting chisel and coring ring are in the same plane with only 0,005 m difference in diameter, as opposed to the techniques where the casing is forced into the Soil by hydraulic cylinder, only very low pressure must be applied in order to force the cylinder into the Soil, with this drilling technique. The Soil sampler was adapted to a specially designed off road vehicle capable of traveling on adverse field conditions. The quality of the VAS samples were compared with undisturbed samples taken from a Soil Block using laboratory tests. The tests conducted were the triaxial undrained compression test and consolidation test. The results demonstrated that the Soil sampler proposed is capable to take undisturbed Soil samples of clay Soil up to 0,6 m with the same quality of the traditional Soil Block, witch is much more time consuming
Jose Antonio Silvaguzman - One of the best experts on this subject based on the ideXlab platform.
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evaluation of accelerated decay of wood plastic composites by xylophagus fungi
International Biodeterioration & Biodegradation, 2009Co-Authors: Maria Guadalupe Lomeliramirez, Hector Guillermo Ochoaruiz, Francisco Javier Fuentestalavera, Salvador Garciaenriquez, M A Cerpagallegos, Jose Antonio SilvaguzmanAbstract:The resistance to fungal attack of wood plastic composites (WPCs) containing 40% polypropylene and 60% either pine, maple or oak, wt%/wt%, was examined. WPCs specimens were made using the hot press system. Resistance to decay was evaluated using Soil Block and agar tests. Test specimens were exposed to either white-rot fungi, Trametes versicolor or Phanerochaete chrysosporium, or the brown-rot fungi Gloeophyllum trabeum or Postia placenta for six or 12 weeks. Moisture content and weight loss were used to assess the extent of decay of WPCs. Rates of decay in WPCs exposed in Soil-Block tests were greater than those exposed in the agar. WPCs containing either maple or oak were more susceptible to fungal attack then those containing pine.
Christophe Cudennec - One of the best experts on this subject based on the ideXlab platform.
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Relevance of a near infrared spectral index for assessing tillage and fertilization effects on Soil water retention
Soil and Tillage Research, 2019Co-Authors: Inès Soltani, Youssef Fouad, Didier Michot, P. Pichelin, Christophe CudennecAbstract:Agricultural practices are expected to have significant effects on Soil physical properties, such as Soil structure and Soil water retention (SWR) properties are among the relevant properties that can be used to assess these effects. Ex-situ measurements are costly and time-consuming. Visible (vis) and near infrared (NIR) spectroscopy has been widely used as a rapid, cost-effective and nondestructive technique to predict many Soil properties, including Soil water content (SWC). In this study, we explored the ability of vis-NIR to assess the effects of Soil tillage and fertilization on SWR. The study was performed on silty Soil samples with 10.4 g kg(-1) of organic carbon content and a pH of 5-6.5. Undisturbed Soil Blocks were collected from an experimental station located in Brittany, France. In 2012, the field was designed as two separate experiments, each with a different tillage system (conventional tillage (CT) and shallow tillage (ST)). For each experiment, two fertilizer types were considered (mineral and organic). Six undisturbed Soil Blocks were sampled at each of two depths (0-15 cm and 15-25 cm) and from each agricultural practice. Soil was sampled on two dates: before starting the treatment (2012) and after 5 years of agricultural practices (2017). From each Soil Block, four aggregates 3-4 cm wide and 5-6 cm long were collected. The whole aggregates were set at a number of matric potentials, from saturation to the permanent wilting point (pF = 4.2). At a given pressure head, Soil samples were scanned in triplicate to acquire reflectance spectra from 400 to 2500 rim using a handheld spectrometer (ASD Fieldspeca (R)). We focused on the absorption band near 1920 nm and used a new NIR spectral index based on the band's full width at half maximum, called SWSI. Our results showed a linear relation between SWSI and SWC (R-2 > 0.99). Moreover, the slope and intercept of this linear relation were significantly correlated with water holding capacity (WHC) and Soil quality. Using these parameters, we found that SWR and Soil physical quality under CT were significantly greater under cattle manure (CTC) than under mineral fertilizer (CTM) or at TO. This significant effect was more pronounced at 15-25 cm. In ST treatments, SWR properties and Soil quality were significantly lower than at TO. More importantly, our results show that the slope and intercept of the linear relation offer a way to summarize and assess the effects of agricultural practices on SWR properties and Soil structural quality.