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Search Results: 1 - 10 of 309833 matches for " Lourival Marin;Guimar?es Júnior "
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The adhesive effect on the properties of particleboards made from sugar cane bagasse generated in the distiller
Rafael Farinassi Mendes,Lourival Marin Mendes,José Benedito Guimares Júnior,Rosimeire Cavalcante dos Santos
Revista de Ciências Agrárias , 2009,
Abstract: The objective was to evaluate the effect of the adhesive type and its different contents on sugar cane bagasse particleboards. The panels were produced using Urea-Formaldehyde (UF) and Phenol-Formaldehyde (PF) adhesives. Three adhesive contents were tested: 6, 9 and 12%. The boards were made by using an 8-minute press closing time, pressure of 40kgf/cm2, and temperature of 160oC for the UF adhesive and 180oC for the PF adhesive. It was concluded that: The UF adhesive was statistically equal or better than PF adhesive considering all properties evaluated. The adhesive contents of 9 and 12% were statistically equal, but both were superior to 6% considering the physical properties. The mechanical properties did not present statistical differences, except for rupture modulus. The best panels were produced using UF at 9%, but they did not attend the norm CS 236-66 for mechanical properties, therefore it is necessary manipulations of the processing variables. O objetivo foi avaliar o efeito do tipo de adesivo e de seus diferentes teores na produ o de painéis aglomerados com baga o de cana. Os painéis foram produzidos utilizando os adesivos Uréia-Formaldeido (UF) e Fenol-Formaldeido (FF) a 6, 9 e 12%. O ciclo de prensagem utilizado foi de 40kgf/cm2, temperatura de 160oC para UF e 180oC para FF, por 8 minutos. Concluiu-se que: O adesivo UF se mostrou estatisticamente igual ou superior a FF em todas as propriedades avaliadas. Para os teores de adesivo, nas propriedades físicas, os teores 9 e 12% se mostraram estatisticamente iguais, mas superiores a 6%; já nas propriedades mecanicas n o houve diferen a estatística, com exce o do módulo de ruptura. Os melhores painéis foram produzidos com UF e 9% de teor de adesivo, sendo que estes n o atenderam a norma CS 236-66 para propriedades mecanicas, sendo necessárias manipula es nas variáveis de processamento.
Wood paticleboards made from residues obtained in the veneer production of eucalypt species and provenances
José Benedito Guimares Júnior,Lourival Marin Mendes,Rafael Farinassi Mendes,Fábio Akira Mori
CERNE , 2011,
Abstract: This work aimed the evaluation of 15 (fifteen) provenances of three eucalypt species: Eucalyptus cloeziana, Eucalyptus grandis and Eucalyptus saligna. The trees were 31 years old and the test was developed in the campus of the Universidade Federal de Lavras. Six particleboards for each provenance were made by using the residues generated in the veneer production of this material. It was used urea-formaldehyde at 8% resin level and paraffin at 1%, both according to their respective solid content. The boards were produced by using a pressing cycle with temperature of 160 oC, specific pressure of 40kgf/cm2 and pressing time of 8 minutes. From the results, it was concluded that the specie Eucalyptus saligna was the best one in terms of water absorption. The 43 provenance of Eucalyptus grandis showed the best development of thickness swelling. Superior results of compression and elastic modulus were found to Eucalyptus cloeziana. The provenance of number 10695 of the specie Eucalyptus grandis presented the best results for elastic and rupture modulus. In general, the provenance 10695 and species of Eucalyptus grandis showed the greatest potential for production of particleboard.
Plywood boards of Eucalyptus: a case study of species and provenances
José Benedito Guimares Júnior,Lourival Marin Mendes,Rafael Farinassi Mendes,Fábio Akira Mori
CERNE , 2009,
Abstract: This work aimed at evaluating 15 provenances of Eucalyptus cloeziana, Eucalyptus grandis and Eucalypotus salignafor multilaminated plywood boards manufacturing. Six boards for each provenance were made. Phenol-formaldehyde adhesive with320g/m2 glue content was used. The utilized pressing cycle was of 15kgf/cm2, at the temperature of 150oC during 10 minutes. From theresults obtained regarding the physical properties, the species of Eucalyptus cloeziana and Eucalyptus saligna performed better. In themechanical tests, MOE presented itself above the demands of the norm with the exception of provenance 7785 of Eucalyptus saligna,in which stress was performed parallel to the cover fibers. For parallel MOR, only the provenances 9789 and 10695 of Eucalyptusgrandis and 97852 of Eucalyptus cloeziana managed to reach the demands of the norm ABNT 31:000.05-001/2. For shearing stressand failure in wood, all the provenances and species showed themselves above the demands, with the exception of 10634; 48 and 9753of Eucalyptus grandis.
Selection of clones of Eucalyptus urophylla for plywood production
José Benedito Guimares Júnior,Lourival Marin Mendes,Rafael Farinassi Mendes,Bárbara Maria Ribeiro Guimares
CERNE , 2012,
Abstract: This work aimed at the evaluation of six (6) Eucalyptus urophylla clones of Companhia Mineira Metais – Unidade Agroflorestal (VM-AGRO) for making particleboard panels. Six (6) panels to each clone studies were produced. About 320g/m2 of Phenol phormol aldehyde adhesives Were utilized. The pressing cycle parameters were: pressure of 1.47MPa, temperature of 150oC and 10 minutes of pressing time. It was concluded that clones of Eucalyptus urophylla show a great potential for production of particleboard panels, since they presented values of physical and mechanical properties above the ones referenced in literature and highly superior to those required by the ABNT Standards 31:000.05-00/2 (static bending) and EN 314-2 (shearing resistance), the tested clones can be used for producing concrete mold (FOR). The clone which stood out the most in all the properties tested was the clone 36.
The adhesive effect on the properties of particleboards made from sugar cane bagasse generated in the distiller
Mendes,Rafael Farinassi; Mendes,Lourival Marin; Júnior,José Benedito Guimares; Santos,Rosimeire Cavalcante dos; Bufalino,Lina;
Revista de Ciências Agrárias , 2009,
Abstract: the objective was to evaluate the effect of the adhesive type and its different contents on sugar cane bagasse particleboards. the panels were produced using urea-formaldehyde (uf) and phenol-formaldehyde (pf) adhesives. three adhesive contents were tested: 6, 9 and 12%. the boards were made by using an 8-minute press closing time, pressure of 40kgf/cm2, and temperature of 160oc for the uf adhesive and 180oc for the pf adhesive. it was concluded that: the uf adhesive was statistically equal or better than pf adhesive considering all properties evaluated. the adhesive contents of 9 and 12% were statistically equal, but both were superior to 6% considering the physical properties. the mechanical properties did not present statistical differences, except for rupture modulus. the best panels were produced using uf at 9%, but they did not attend the norm cs 236-66 for mechanical properties, therefore it is necessary manipulations of the processing variables.
Sele??o de clones de Eucalyptus urophylla para produ??o de compensados
Guimares Júnior, José Benedito;Mendes, Lourival Marin;Mendes, Rafael Farinassi;Guimares, Bárbara Maria Ribeiro;Oliveira, Stefania Lima;
CERNE , 2012, DOI: 10.1590/S0104-77602012000400017
Abstract: this work aimed at the evaluation of six (6) eucalyptus urophylla clones of companhia mineira metais - unidade agroflorestal (vm-agro) for making particleboard panels. six (6) panels to each clone studies were produced. about 320g/m2 of phenol phormol aldehyde adhesives were utilized. the pressing cycle parameters were: pressure of 1.47mpa, temperature of 150oc and 10 minutes of pressing time. it was concluded that clones of eucalyptus urophylla show a great potential for production of particleboard panels, since they presented values of physical and mechanical properties above the ones referenced in literature and highly superior to those required by the abnt standards 31:000.05-00/2 (static bending) and en 314-2 (shearing resistance), the tested clones can be used for producing concrete mold (for). the clone which stood out the most in all the properties tested was the clone 36.
Efeito da incorpora??o de casca de café nas propriedades físico-mecanicas de painéis aglomerados de Eucalyptus urophylla S.T. Blake
Mendes, Rafael Farinassi;Mendes, Lourival Marin;Guimares Júnior, José Benedito;Mori, Fábio Akira;César, Antonia Amanda da Silva;
Ciência e Agrotecnologia , 2010, DOI: 10.1590/S1413-70542010000300012
Abstract: the objective of this study was to evaluate the influence of the incorporation of coffee husks in the production of particleboard with eucalyptus urophylla s.t. blake. the panels were produced incorporating 25%, 50%, and 75% of coffee husks at three levels of resin phenol-formaldehyde (6, 9 and 12%) and 1% of paraffin. the nominal density of the panels was 0.7 g/cm3 and the cycle of pressing consisted in a pressure of 3.92 mpa under a temperature of 180°c for 8 minutes. by the results it was possible to observe that the physical properties of the particleboard have a linear relationship decreasing with the increase in the level of resin, and increasing with the increase in the percentage of coffee husks, showing higher values of water absorption and thickness swelling. the mechanical properties show a linear relationship growing with the increase of resin level, and decreasing with a reduction the percentage of coffee husk association. the way that the search was conducted, the incorporation of the coffee husks harms the quality of the panels produced.
Sistemas de integra??o lavoura-pecuária na regi?o do Cerrado
Vilela, Lourival;Martha Junior, Geraldo Bueno;Macedo, Manuel Cláudio Motta;March?o, Robélio Leandro;Guimares Júnior, Roberto;Pulrolnik, Karina;Maciel, Giovana Alcantara;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011001000003
Abstract: the objective of this work was to analyze the benefits and the potential prospects of integrated crop-livestock systems in the process of crop and pasture intensification in the cerrado, and to point out the main information gaps about the system. the main benefits of crop-livestock integration are: improved chemical, physical and biological properties of the soil; reduction of diseases, pests and weed outbreaks occurrence; higher crop and animal productivity; and risk reduction due to diversification of activities. however, the adoption of the crop-livestock system is still low, probably due to the greater complexity of the system. concentrating efforts on the factors that limit the system's adoption is strategic for new studies. the search for better soil cover for the no tillage system, through forage grasses, can boost the adoption of integrated crop-livestock in the cerrado. it is expected that the adoption of integrated crop-livestock systems improve the socioeconomic and environmental sustainability of the farm and of its region of influence.
EFFECT OF LAMINATE INCLUSION AND THE TYPE OF ADHESIVE IN THE PROPERTIES OF OSB PANELS OF THE WOOD FROM Pinus oocarpa
Rafael Farinassi Mendes,Lourival Marin Mendes,Amélia Guimares Carvalho,Adriana Fantin Ayres da Silva
Revista Ciência da Madeira , 2012,
Abstract: The aim of the study was to evaluate the influence of laminate inclusion and the type of adhesive on the physical and mechanical properties of OSB panels produced from the wood of Pinus oocarpa. The experimental design consisted of four treatments. Laminateinclusion and urea-formaldehyde and phenol-formaldehyde adhesives applied in combination with the panel layer were evaluated. For each treatment, three panels with nominal density of 0.65 g.cm-3, 1% to 6% paraffin and adhesive were produced. In the manufacturing of thepanels, temperature of 180 ° C, pressure of 3.95 MPa and pressing time of 8 minutes were adopted. From the results it is concluded that: the species Pinus oocarpa has great potential for use in the production of OSB panels; the laminate inclusion resulted in significant improvement in the properties of water absorption and thickness swelling after immersion for two hours, as well as in the modulus of elasticity and modulus of rupture in parallel direction; and the panels made with urea-formaldehyde adhesives in the core and phenol-formaldehydeon the faces statistically equal to panels only with the phenol-formaldehyde adhesive in statistically, except in the internal bonding property.
Eucalyptus urophylla stands wood utilization at two different ages for production of particleboard panels
Lourival Marin Mendes,Setsuo Iwakiri,Fabio Akira Mori,José Benedito Guimares Junior
CERNE , 2009,
Abstract: This work aimed to assess the quality of wood particle panels manufactured with wood from Eucalyptus urophylla stands at age 7 and at age 12 years. To that end, particleboard, oriented strand board (OSB) and cement-bonded panels were produced in a laboratory and then analyzed for the following physical and mechanical properties: water absorption and thickness swell 2 and 24 hours after immersion, internal bond, compression parallel, as well as MOE and MOR from static bending. The obtained results demonstrate that tree age had little influence on the physical and mechanical properties of particleboard, OSB and cement-bonded panels. After evaluating the physical and mechanical properties of these three panel types, all manufactured with wood from Eucalyptus urophylla stands at age 7 and at age 12, we can argue that our results are satisfactory in comparison to existing literature results.
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