Pub Date : 2021-12-01DOI: 10.4067/s0718-221x2022000100411
D. Pop, M. Timar, A. Varodi, E. Beldean
This paper investigates the potential of clove (Eugenia caryophyllata) essential oil (C-EO) as a wood protection system for use in cultural heritage conservation. The preventive and curative antifungal efficacy of C-EO was compared to a boron containing wood preservative (Diffusit S) in two laboratory tests on European beech (Fagus sylvatica) and Scots pine sapwood (Pinus sylvestris) mini-blocks. Non-sterile, air-infected wood samples were employed in the first test, while wood samples with active attack, as result of inoculation with three fungal strains isolated from cultural heritage sites, in the second test. Untreated controls and C-EO-treated wood blocks were incubated up to 150 days to monitor and quantify fungal growth. The experimental results showed antifungal efficacy of C-EO to be higher than that of the boron wood preservative at the concentrations used. Concentrations of C-EO 5 % 10 % in ethyl alcohol prevented mould growth for at least 150 days, while a concentration of 10 % delayed or suppressed active attack by decay fungi. This effect, determined up to 90 days of incubation, was dependant on the type of fungus.
{"title":"An evaluation of clove (Eugenia caryophyllata) essential oil as a potential alternative antifungal wood protection system for cultural heritage conservation","authors":"D. Pop, M. Timar, A. Varodi, E. Beldean","doi":"10.4067/s0718-221x2022000100411","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100411","url":null,"abstract":"This paper investigates the potential of clove (Eugenia caryophyllata) essential oil (C-EO) as a wood protection system for use in cultural heritage conservation. The preventive and curative antifungal efficacy of C-EO was compared to a boron containing wood preservative (Diffusit S) in two laboratory tests on European beech (Fagus sylvatica) and Scots pine sapwood (Pinus sylvestris) mini-blocks. Non-sterile, air-infected wood samples were employed in the first test, while wood samples with active attack, as result of inoculation with three fungal strains isolated from cultural heritage sites, in the second test. Untreated controls and C-EO-treated wood blocks were incubated up to 150 days to monitor and quantify fungal growth. The experimental results showed antifungal efficacy of C-EO to be higher than that of the boron wood preservative at the concentrations used. Concentrations of C-EO 5 % 10 % in ethyl alcohol prevented mould growth for at least 150 days, while a concentration of 10 % delayed or suppressed active attack by decay fungi. This effect, determined up to 90 days of incubation, was dependant on the type of fungus.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"13 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83667556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-01DOI: 10.4067/s0718-221x2022000100408
J. B. Acheampong, Bernard Effah, K. Antwi, Ernest Wenia Achana
Physical properties are major characteristics that validate biomaterials’ adaptability to commercial utilization. The moisture content, density, swelling, and shrinkage within male and female Borassus aethiopum were assessed. Green and dry moisture content, and density were tested with the oven-dry method while swelling and shrinkage were evaluated using the water-saturation test and oven-dry methods respectively. Unlike moisture content, density decreased towards the crowns and radially from the peripheries to their cores. Directional swelling decreased as: Radial > Tangential > Longitudinal. Volumetric swelling was greatest at the core of the base (6,99 %) but at least at the periphery within the middle of the male (2,89 %). However, the female recorded much swelling at the core of its mid-portion (6,23 %) and least (4,01 %) at the crown periphery. Directional shrinkage decreased identically as the male variety while the volumetric shrinkage for both varieties was not consistent. The peripheries had less moisture content, better dimensional stability and density (which influences wood strength) at the butt than those of the core indicating the peripheries would maintain its original dimension and strength when subjected to environmental changes and be more viable for structural works than the core.
{"title":"Physical properties of palmyra palm wood for sustainable utilization as a structural material","authors":"J. B. Acheampong, Bernard Effah, K. Antwi, Ernest Wenia Achana","doi":"10.4067/s0718-221x2022000100408","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100408","url":null,"abstract":"Physical properties are major characteristics that validate biomaterials’ adaptability to commercial utilization. The moisture content, density, swelling, and shrinkage within male and female Borassus aethiopum were assessed. Green and dry moisture content, and density were tested with the oven-dry method while swelling and shrinkage were evaluated using the water-saturation test and oven-dry methods respectively. Unlike moisture content, density decreased towards the crowns and radially from the peripheries to their cores. Directional swelling decreased as: Radial > Tangential > Longitudinal. Volumetric swelling was greatest at the core of the base (6,99 %) but at least at the periphery within the middle of the male (2,89 %). However, the female recorded much swelling at the core of its mid-portion (6,23 %) and least (4,01 %) at the crown periphery. Directional shrinkage decreased identically as the male variety while the volumetric shrinkage for both varieties was not consistent. The peripheries had less moisture content, better dimensional stability and density (which influences wood strength) at the butt than those of the core indicating the peripheries would maintain its original dimension and strength when subjected to environmental changes and be more viable for structural works than the core.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"159 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74188332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-01DOI: 10.4067/s0718-221x2022000100409
K. A. de Oliveira, Carolina A. Barros Oliveira, Julio C. Molina
Indian cedar (Acrocarpus fraxinifolius) is a wood species that occurs naturally in India, Myanmar (Burma) and Bangladesh, and has a high commercial value, with characteristics like mahogany and native cedars. The planting of Indian cedar has been undertaken in Brazil, but there is little information available regarding the characterization of the species. Therefore, considering its timber potential and its possibility of development in the country, the present work aimed to evaluate the physical, chemical, and mechanical properties of 9-year-old Indian cedar wood, planted in the southern region of Brazil. A low specific mass (502 kg/m3), low average dimensional stability (anisotropy coefficient of 2,09 %) was observed, in addition to the low content of extractives (1,94 %). From the mechanical characterization, an average value for the elastic modulus of 8963 MPa was obtained, and for the compressive strength parallel to the grain the average and characteristic values were 32,14 MPa and 21,46 MPa, respectively. This indicates that this wood belongs to resistance class C20 (dicotyledons). The results obtained classify the wood for use in light, external, or internal civil construction
{"title":"Physical, chemical and mechanical characterization of Acrocarpus fraxinifolius cultivated in Sao Paulo","authors":"K. A. de Oliveira, Carolina A. Barros Oliveira, Julio C. Molina","doi":"10.4067/s0718-221x2022000100409","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100409","url":null,"abstract":"Indian cedar (Acrocarpus fraxinifolius) is a wood species that occurs naturally in India, Myanmar (Burma) and Bangladesh, and has a high commercial value, with characteristics like mahogany and native cedars. The planting of Indian cedar has been undertaken in Brazil, but there is little information available regarding the characterization of the species. Therefore, considering its timber potential and its possibility of development in the country, the present work aimed to evaluate the physical, chemical, and mechanical properties of 9-year-old Indian cedar wood, planted in the southern region of Brazil. A low specific mass (502 kg/m3), low average dimensional stability (anisotropy coefficient of 2,09 %) was observed, in addition to the low content of extractives (1,94 %). From the mechanical characterization, an average value for the elastic modulus of 8963 MPa was obtained, and for the compressive strength parallel to the grain the average and characteristic values were 32,14 MPa and 21,46 MPa, respectively. This indicates that this wood belongs to resistance class C20 (dicotyledons). The results obtained classify the wood for use in light, external, or internal civil construction","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"22 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80119463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-01DOI: 10.4067/s0718-221x2022000100405
Antonio Villasante, S. Vignote, Á. Fernández-Serrano, R. Laina
Samples of wood from Populus × canadensis (9,5 % moisture) were treated with olive oil at 195 °C simultaneously with 15 % or 30 % compression densification, and the results were compared with samples subjected to oil heat treatment without densification, and control samples. The density of the treated samples increased by 18 %, 43 % and 1,5 % respectively, and barely changed over the six subsequent months stored inside the laboratory room (at approximately 65 % RH, 20 °C). This was due to the fact that the slight weight increment caused by the additional moisture content was offset by the increase in volume from the springback effect. When subjected to atmospheres with different relative humidities, the treated samples stabilised at the same time as the control samples, although the treated samples had a significantly lower moisture absorption than the control samples. It was also observed that the hygroscopic shrinkage in oil heat densification treatment samples was approximately half those of the control samples. The initial densification was partially lost as a result of springback: approximately 3 % in the first springback at a relative humidity of 65 % RH, and an additional 4 % in the second springback to a relative humidity of 85 % RH. Once this latter relative humidity had been attained, no new losses in densification were observed. The ageing of the oil used in the treatment caused a slight loss of densification in the densest samples.
{"title":"Simultaneous treatment with oil heat and densification on physical properties of Populus × Canadensis wood","authors":"Antonio Villasante, S. Vignote, Á. Fernández-Serrano, R. Laina","doi":"10.4067/s0718-221x2022000100405","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100405","url":null,"abstract":"Samples of wood from Populus × canadensis (9,5 % moisture) were treated with olive oil at 195 °C simultaneously with 15 % or 30 % compression densification, and the results were compared with samples subjected to oil heat treatment without densification, and control samples. The density of the treated samples increased by 18 %, 43 % and 1,5 % respectively, and barely changed over the six subsequent months stored inside the laboratory room (at approximately 65 % RH, 20 °C). This was due to the fact that the slight weight increment caused by the additional moisture content was offset by the increase in volume from the springback effect. When subjected to atmospheres with different relative humidities, the treated samples stabilised at the same time as the control samples, although the treated samples had a significantly lower moisture absorption than the control samples. It was also observed that the hygroscopic shrinkage in oil heat densification treatment samples was approximately half those of the control samples. The initial densification was partially lost as a result of springback: approximately 3 % in the first springback at a relative humidity of 65 % RH, and an additional 4 % in the second springback to a relative humidity of 85 % RH. Once this latter relative humidity had been attained, no new losses in densification were observed. The ageing of the oil used in the treatment caused a slight loss of densification in the densest samples.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"83 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90262371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-01DOI: 10.4067/s0718-221x2022000100406
Anamika Sahu, S. Tripathi, Sauradipta Ganguly, A. Sumi
An eco-friendly alternative of Pongamia pinnata seed oil was tested for fumigation of imported Tectona grandis and Pinus spp. (Southern yellow pine) against sap stain and mould fungi at 25°C± 2°C and 75 % ± 5 % relative humidity. Veneeer and block samples of both species, and Petri dishes with agar media were fumigated with three different concentrations (w/v) of Pongamia pinnata seed oil and exhibited significant inhibition of fungal growth in comparison to the control sets, with the highest concentration of 6,4 g/ 8 mL3 proving to be the most lethal. Tectona grandis exhibited no infestation of sapstain and mould in either type of specimens whereas highly perishable Southern yellow pine displayed slight infestation of 4 % and 5 % with 1,6 g/ 2 mL3 of Pongamia pinnata seed oil for venner and block specimens as compared to 18 % and 20 % infestation observed in respective controls. The infestation on Southern yellow pine reduced to 1 % and 2 % respectively for veneers and blocks with 4 g/ 5 mL3 of Pongamia pinnata seed oil and was completely inhibited at 6,4 g/ 8 mL3 for both type of Southern yellow pine specimens. Petri plates returned similar findings where all higher concentrations inhibited mould growth completely and the lowest concentration exhibited meagre mould growth. Sapstain was inhibited successfully by all three concentrations of Pongamia pinnata seed oil on agar media.
{"title":"Fumigation of imported Tectona grandis and southern yellow pine with Pongamia pinnata seed oil against sapstain and mould","authors":"Anamika Sahu, S. Tripathi, Sauradipta Ganguly, A. Sumi","doi":"10.4067/s0718-221x2022000100406","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100406","url":null,"abstract":"An eco-friendly alternative of Pongamia pinnata seed oil was tested for fumigation of imported Tectona grandis and Pinus spp. (Southern yellow pine) against sap stain and mould fungi at 25°C± 2°C and 75 % ± 5 % relative humidity. Veneeer and block samples of both species, and Petri dishes with agar media were fumigated with three different concentrations (w/v) of Pongamia pinnata seed oil and exhibited significant inhibition of fungal growth in comparison to the control sets, with the highest concentration of 6,4 g/ 8 mL3 proving to be the most lethal. Tectona grandis exhibited no infestation of sapstain and mould in either type of specimens whereas highly perishable Southern yellow pine displayed slight infestation of 4 % and 5 % with 1,6 g/ 2 mL3 of Pongamia pinnata seed oil for venner and block specimens as compared to 18 % and 20 % infestation observed in respective controls. The infestation on Southern yellow pine reduced to 1 % and 2 % respectively for veneers and blocks with 4 g/ 5 mL3 of Pongamia pinnata seed oil and was completely inhibited at 6,4 g/ 8 mL3 for both type of Southern yellow pine specimens. Petri plates returned similar findings where all higher concentrations inhibited mould growth completely and the lowest concentration exhibited meagre mould growth. Sapstain was inhibited successfully by all three concentrations of Pongamia pinnata seed oil on agar media.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"226 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75766231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-01DOI: 10.4067/s0718-221x2022000100404
D. Koynov, R. Grigorov, Miglena Valyova
This study presents an opportunity for rational utilization of poplar wood peeler cores in the production of glued laminated timber (glulam) beams. An approach for optimal use of small-diameter raw material with a circular cross-section is also proposed in order to obtain a final product in a significantly high quantitative yield. The applied novel method of sawing the peeler cores and subsequent combination of gluing the obtained lamellas allows to achieve: reduction of labor and energy consumption in the processing; rational utilization of this waste raw material; obtaining a product sought by consumers; opportunity to implement technology for the production of glulam from peeler cores. The results showed that sawing the peeler cores and obtaining lamellas with a trapezoidal cross-section leads to a high quantitative yield of 76,3 %. The final quantitative yield in subsequent technological operations in the manufacturing of engineered wood of glulam type reaches 48,8 % of the volume of raw material. In addition, equations have been working are used for the determination of the most suitable sizes of the lamellas, depending on the diameter and the kerf width.
{"title":"A novel method for producing a glulam from the wood of peeler cores","authors":"D. Koynov, R. Grigorov, Miglena Valyova","doi":"10.4067/s0718-221x2022000100404","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100404","url":null,"abstract":"This study presents an opportunity for rational utilization of poplar wood peeler cores in the production of glued laminated timber (glulam) beams. An approach for optimal use of small-diameter raw material with a circular cross-section is also proposed in order to obtain a final product in a significantly high quantitative yield. The applied novel method of sawing the peeler cores and subsequent combination of gluing the obtained lamellas allows to achieve: reduction of labor and energy consumption in the processing; rational utilization of this waste raw material; obtaining a product sought by consumers; opportunity to implement technology for the production of glulam from peeler cores. The results showed that sawing the peeler cores and obtaining lamellas with a trapezoidal cross-section leads to a high quantitative yield of 76,3 %. The final quantitative yield in subsequent technological operations in the manufacturing of engineered wood of glulam type reaches 48,8 % of the volume of raw material. In addition, equations have been working are used for the determination of the most suitable sizes of the lamellas, depending on the diameter and the kerf width.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"2014 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86560116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-01DOI: 10.4067/s0718-221x2022000100407
Ç. Altay, Hilmi Toker, Ergun Baysal, I. Babahan
This study was made to determine surface characteristics such as colour, gloss, and surface hardness changes of Oriental beech (Fagus orientalis). The wood specimens were firstly impregnated with some fireretardants (FRs) and primed with epoxy resin (EPR) and then coated with polyurethane/polyurea hybrid resin (PUU). Oriental beech was impregnated with 3 % aqueous solution of boric acid (BA), borax (BX), boric acid and borax mixture (1:1), and ammonium sulphate (AS). While Sikafloor®-156 was used for epoxy coating (EPR), Sikalastic®-851 R was used for polyurethane/polyurea hybrid coating (PUU). According to our results, all treatment groups gave negative lightness stability values after accelerated weathering. The colour stability of epoxy resin coated Oriental beech was higher than that of polyurethane/polyurea hybrid resin coated Oriental beech. Except for boric acid impregnated and polyurethane/polyurea hybrid resin coated Oriental beech, all fire-retardants treatment before polyurethane/polyurea hybrid resin and epoxy resin coatings decreased the gloss losses of Oriental beech after accelerated weathering. Fire-retardants impregnation before epoxy resin and polyurethane/polyurea hybrid resin coatings improved the surface hardness values of Oriental beech after accelerated weathering.
{"title":"Some surface characteristics of oriental beech wood impregnated with some fire-retardants and coated wıth polyurea/polyurethane hybrid and epoxy resins","authors":"Ç. Altay, Hilmi Toker, Ergun Baysal, I. Babahan","doi":"10.4067/s0718-221x2022000100407","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100407","url":null,"abstract":"This study was made to determine surface characteristics such as colour, gloss, and surface hardness changes of Oriental beech (Fagus orientalis). The wood specimens were firstly impregnated with some fireretardants (FRs) and primed with epoxy resin (EPR) and then coated with polyurethane/polyurea hybrid resin (PUU). Oriental beech was impregnated with 3 % aqueous solution of boric acid (BA), borax (BX), boric acid and borax mixture (1:1), and ammonium sulphate (AS). While Sikafloor®-156 was used for epoxy coating (EPR), Sikalastic®-851 R was used for polyurethane/polyurea hybrid coating (PUU). According to our results, all treatment groups gave negative lightness stability values after accelerated weathering. The colour stability of epoxy resin coated Oriental beech was higher than that of polyurethane/polyurea hybrid resin coated Oriental beech. Except for boric acid impregnated and polyurethane/polyurea hybrid resin coated Oriental beech, all fire-retardants treatment before polyurethane/polyurea hybrid resin and epoxy resin coatings decreased the gloss losses of Oriental beech after accelerated weathering. Fire-retardants impregnation before epoxy resin and polyurethane/polyurea hybrid resin coatings improved the surface hardness values of Oriental beech after accelerated weathering.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"323 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78912494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-01DOI: 10.4067/s0718-221x2022000100402
Ha Tien Manh, A. Redman, Chuong Pham Van, Bui Duy Ngoc
This study investigated the mass transfer properties (permeability and mass diffusivity) in the longitudinal, radial and tangential directions of plantation-grown Acacia mangium in VinhPhuc province,northeast, Vietnam. These properties will be used to complement a conventional drying model in the future. Measurements of gas and liquid permeability were performed using a Porometer (POROLUXTM1000). Mass diffusivity was determined in a constant humidity and temperature chamber using PVC-CHA vaporimeters. Results showed the gas permeability was significant higher than liquid with the descending order of longitudinal, radial, and tangential directions. The permeability anisotropy ratios from the longitudinal to transverse directions of Acacia mangium were much lower than other published species. However, the obvious anisotropy ratios from radial to tangential for both permeability and diffusivity, is one of concerns as they can exacerbate defects during drying. Besides, the high permeability and diffusivity of Acaciamangium compared to some other species reported compounds its relatively fast drying rate.
{"title":"Mass transfer properties of Acacia mangium plantation woodt","authors":"Ha Tien Manh, A. Redman, Chuong Pham Van, Bui Duy Ngoc","doi":"10.4067/s0718-221x2022000100402","DOIUrl":"https://doi.org/10.4067/s0718-221x2022000100402","url":null,"abstract":"This study investigated the mass transfer properties (permeability and mass diffusivity) in the longitudinal, radial and tangential directions of plantation-grown Acacia mangium in VinhPhuc province,northeast, Vietnam. These properties will be used to complement a conventional drying model in the future. Measurements of gas and liquid permeability were performed using a Porometer (POROLUXTM1000). Mass diffusivity was determined in a constant humidity and temperature chamber using PVC-CHA vaporimeters. Results showed the gas permeability was significant higher than liquid with the descending order of longitudinal, radial, and tangential directions. The permeability anisotropy ratios from the longitudinal to transverse directions of Acacia mangium were much lower than other published species. However, the obvious anisotropy ratios from radial to tangential for both permeability and diffusivity, is one of concerns as they can exacerbate defects during drying. Besides, the high permeability and diffusivity of Acaciamangium compared to some other species reported compounds its relatively fast drying rate.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"56 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75592005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-01DOI: 10.4067/s0718-221x2021000100465
Ricardo Rodrigues de Oliveira, Larissa Ferreira Rodrigues, J. F. Mari, Murilo Coelho Naldi, Emerson Gomes Milagres, Benedito Rocha Vital, Angélica de Cássia Oliveira Carneiro, Daniel Henrique Breda Binoti, Pablo Falco Lopes, Hélio Garcia Leite
The differentiation between the charcoal produced from (Eucalyptus) plantations and native forests is essential to control, commercialization, and supervision of its production in Brazil. The main contribution of this study is to identify the charcoal origin using macroscopic images and Deep Learning Algorithm. We applied a Convolutional Neural Network (CNN) using VGG-16 architecture, with preprocessing based on contrast enhancement and data augmentation with rotation over the training set images. on the performance of the CNN with fine-tuning using 360 macroscopic charcoal images from the plantation and native forests. The results pointed out that our method provides new perspectives to identify the charcoal origin, achieving results upper 95 % of mean accuracy to classify charcoal from native forests for all compared preprocessing strategies.
{"title":"Automatic identification of charcoal origin based on deep learning","authors":"Ricardo Rodrigues de Oliveira, Larissa Ferreira Rodrigues, J. F. Mari, Murilo Coelho Naldi, Emerson Gomes Milagres, Benedito Rocha Vital, Angélica de Cássia Oliveira Carneiro, Daniel Henrique Breda Binoti, Pablo Falco Lopes, Hélio Garcia Leite","doi":"10.4067/s0718-221x2021000100465","DOIUrl":"https://doi.org/10.4067/s0718-221x2021000100465","url":null,"abstract":"The differentiation between the charcoal produced from (Eucalyptus) plantations and native forests is essential to control, commercialization, and supervision of its production in Brazil. The main contribution of this study is to identify the charcoal origin using macroscopic images and Deep Learning Algorithm. We applied a Convolutional Neural Network (CNN) using VGG-16 architecture, with preprocessing based on contrast enhancement and data augmentation with rotation over the training set images. on the performance of the CNN with fine-tuning using 360 macroscopic charcoal images from the plantation and native forests. The results pointed out that our method provides new perspectives to identify the charcoal origin, achieving results upper 95 % of mean accuracy to classify charcoal from native forests for all compared preprocessing strategies.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"18 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80984904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-01DOI: 10.4067/s0718-221x2021000100462
Wengang Hu, Bin Chen, Xiaowen Lin, Huiyuan Guan
The effect of loading type (tension, compression and bolt-bearing) on mechanical properties (elastic modulus, Poisson’s ratio and ultimate strength) of Moso bamboo (Phyllostachys heterocycla var. pubescens) in longitudinal direction was evaluated in this study. In addition, experimental and numerical tests were conducted to evaluate withdrawal force capacity and bending moment resistances of a novel demountable bamboo-bolt joint considering effect of loading type on mechanical parameters used in finite element method. The results showed that loading type had significant effect on mechanical properties of Moso bamboo, especially, for ultimate strength; the values of mechanical properties evaluated in this study measured in tension were all much higher than those measured in bolt-bearing state and followed by compression accordingly; in tension, the tensile elastic modulus and Poisson’s ratio measured at outer surface were bigger than those at inner surface, respectively; finite element method got more accurate results using the mechanical parameters measured in compression than those in tension and bolt-bearing states; the bamboo-bolt joint proposed in this study can be used in lightweight bamboo structures through improving the embedding strength of beech wood in bamboo culm. In conclusion, one should consider the loading type used to obtain the mechanical para meters inputted in finite element method. In addition, further studies will focus on effect of size and geometry of samples used to determine mechanical properties used in finite element method, and the method of improving embedding strength of beech wood in bamboo culm to increase withdrawal force capacity and bending moment resistances of the demountable bamboo-bolt joint proposed in this study.
{"title":"Experimental and numerical study on a novel bamboo joint for furniture considering effect of loading type on mechanical parameters used in finite element method","authors":"Wengang Hu, Bin Chen, Xiaowen Lin, Huiyuan Guan","doi":"10.4067/s0718-221x2021000100462","DOIUrl":"https://doi.org/10.4067/s0718-221x2021000100462","url":null,"abstract":"The effect of loading type (tension, compression and bolt-bearing) on mechanical properties (elastic modulus, Poisson’s ratio and ultimate strength) of Moso bamboo (Phyllostachys heterocycla var. pubescens) in longitudinal direction was evaluated in this study. In addition, experimental and numerical tests were conducted to evaluate withdrawal force capacity and bending moment resistances of a novel demountable bamboo-bolt joint considering effect of loading type on mechanical parameters used in finite element method. The results showed that loading type had significant effect on mechanical properties of Moso bamboo, especially, for ultimate strength; the values of mechanical properties evaluated in this study measured in tension were all much higher than those measured in bolt-bearing state and followed by compression accordingly; in tension, the tensile elastic modulus and Poisson’s ratio measured at outer surface were bigger than those at inner surface, respectively; finite element method got more accurate results using the mechanical parameters measured in compression than those in tension and bolt-bearing states; the bamboo-bolt joint proposed in this study can be used in lightweight bamboo structures through improving the embedding strength of beech wood in bamboo culm. In conclusion, one should consider the loading type used to obtain the mechanical para meters inputted in finite element method. In addition, further studies will focus on effect of size and geometry of samples used to determine mechanical properties used in finite element method, and the method of improving embedding strength of beech wood in bamboo culm to increase withdrawal force capacity and bending moment resistances of the demountable bamboo-bolt joint proposed in this study.","PeriodicalId":18092,"journal":{"name":"Maderas-ciencia Y Tecnologia","volume":"30 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78954751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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