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1.
Influence of age and trunk positions on physicomechanical properties of Anthocleista grandiflora Gilg wood
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Dorwu, Frank Kofi
; Mensah, Prosper
; Antwi, Kwaku
; de Melo, Rafael Rodolfo
; Pimenta, Alexandre Santos
; de Oliveira Paula, Edgley Alves
; Rusch, Fernando
.
ABSTRACT Population growth and the high demand for the use of wood already consolidated on the market have caused a high demand for forestry resources. This factor motivated the search for other species with properties that satisfy everyday needs in industrial applications. The research aims to characterize the physical-mechanical properties of Anthocleista grandiflora wood. Samples were taken to determine the properties of the three trunks’ base, middle, and top regions at 38, 43, and 47-year-old. Physical (density, moisture content, and volumetric increase) and mechanical tests (flexural strength, elasticity resistance, shear strength, and Janka hardness) were used to characterize the material. The results confirmed that the lowest average moisture content was presented at the base of 38-year-old trees, with values varying from 12.2 to 13.3% in the heartwood and sapwood regions. For density, the base of 47-year-old trees obtained the highest values, with a variation of 434.3–477.3 kg m–3 in the heartwood and sapwood regions. Mechanical flexural strength tests demonstrated that the highest value for the modulus of rupture was 63 MPa, indicated by samples taken from the heartwood of 43-year-old trees. The results show that A. Grandiflora wood can be used for various value-added purposes (construction, furniture, and other equipment). resources applications physicalmechanical physical trunks middle 38 43 47yearold. 47yearold yearold 47 year old. old density (density increase resistance hardness material 38yearold 122 12 2 12. 133 13 3 13.3 43434773 434 477 434.3–477. m3 m m– 6 MPa 43yearold A valueadded added construction, construction (construction furniture equipment. equipment . equipment) 4 1 13. 4343477 434.3–477 434347 434.3–47 43434 434.3–4 4343 434.3– 434.3 434.
2.
Ecological adhesive based on cassava starch: a sustainable alternative to replace urea-formaldehyde (UF) in particleboard manufacture starch ureaformaldehyde urea formaldehyde UF (UF
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Mensah, Prosper
; Melo, Rafael Rodolfo de
; Mitchual, Stephen Jobson
; Owusu, Francis Wilson
; Mensah, Michael Awotwe
; Donkoh, Mark Bright
; Paula, Edgley Alves de Oliveira
; Pedrosa, Talita Dantas
; Rodolfo Junior, Francisco
; Rusch, Fernando
.
ABSTRACT This study assessed the properties of particleboard produced from the replacement of urea formaldehyde with cassava starch. Cassava starch (CS) and urea-formaldehyde (UF) were mixed at percentages of 100/0, 90/10, 70/30, 50/50, and 0/100, respectively. The mixture was added to the wood particles at 15% adhesive content based on the weight of oven-dried particles. Particleboards of sizes 20 mm × 300 mm × 300 mm and a targeted density of 600 kg m–3 were manufactured by hot-pressing at 170 °C, compacting pressure 3.5 MPa for 8 min. Physical and mechanical properties (density, thickness swelling, water absorption, static bending, and hardness) were tested. The physical and mechanical properties also increased in the highest proportions of UF. Comparatively, manufactured with 50% CS + 50% UF, it performed better in all the evaluated properties. Thus, it could adopt the latter mixed ratio in the industry to reduce the quantity and cost of UF and its environmental emissions. The results obtained were adequate and in conformity with international standards. Hence, it could mix cassava starch and urea formaldehyde adhesives in different ratios to get desirable properties. It is possible to conclude that cassava starch could be considered a sustainable alternative adhesive. (CS ureaformaldehyde (UF 1000 100 0 100/0 9010 90 10 90/10 7030 70 30 70/30 5050 50 50/50 0100 0/100 respectively 15 ovendried oven dried 2 60 m3 m 3 m– hotpressing hot pressing 17 C °C 35 5 3. min density, (density swelling absorption bending hardness tested Comparatively Thus emissions standards Hence 100/ 901 9 1 90/1 703 7 70/3 505 50/5 010 0/10 6 90/ 70/ 50/ 01 0/1 0/
3.
Natural Durability of Mimosa tenuiflora and Mimosa caesalpiniaefolia Woods: Two Species from the Brazilian Dry Forest Woods
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Braga, Rodolpho Stephan Santos
; Melo, Rafael Rodolfo de
; Pimenta, Alexandre Santos
; Garlet, Alencar
; Canto, Juliana Lorensi do
; Medeiros Neto, Pedro Nicó de
.
Abstract Knowledge of the characteristics and durability of every wood species is essential so it can be better directed for the correct harnessing. In a wood rot field test, this work aimed to determine the natural durability of timber species from the Brazilian dry forest, Mimosa tenuiflora and Mimosa caesalpiniaefolia . The slats were buried in the ground up to half their length and distributed in the field according to a completely randomized experimental design. Annual assessments were performed to determine the deterioration rate. Furthermore, mass loss and condensed tannin content were quantified. The condensed tannin content found for the species was 4.40% for M. caesalpiniaefolia and 3.99% for M. tenuiflora . The results of 3 years of evaluation of the test make it possible to understand that both species presented durable wood, where M. caesalpiniaefolia presented a deterioration rate of 77.27%, while M. tenuiflora presented 66.27%, making them of high natural durability. harnessing forest design Furthermore quantified 440 4 40 4.40 M 399 99 3.99 7727 77 27 77.27% 6627 66 66.27% 44 4.4 39 9 3.9 772 7 2 77.27 662 6 66.27 4. 3. 77.2 66.2 77. 66.
4.
Catálogo Taxonômico da Fauna do Brasil: Setting the baseline knowledge on the animal diversity in Brazil Brasil
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Boeger, Walter A.
; Valim, Michel P.
; Zaher, Hussam
; Rafael, José A.
; Forzza, Rafaela C.
; Percequillo, Alexandre R.
; Serejo, Cristiana S.
; Garraffoni, André R.S.
; Santos, Adalberto J.
; Slipinski, Adam
; Linzmeier, Adelita M.
; Calor, Adolfo R.
; Garda, Adrian A.
; Kury, Adriano B.
; Fernandes, Agatha C.S.
; Agudo-Padrón, Aisur I.
; Akama, Alberto
; Silva Neto, Alberto M. da
; Burbano, Alejandro L.
; Menezes, Aleksandra
; Pereira-Colavite, Alessandre
; Anichtchenko, Alexander
; Lees, Alexander C.
; Bezerra, Alexandra M.R.
; Domahovski, Alexandre C.
; Pimenta, Alexandre D.
; Aleixo, Alexandre L.P.
; Marceniuk, Alexandre P.
; Paula, Alexandre S. de
; Somavilla, Alexandre
; Specht, Alexandre
; Camargo, Alexssandro
; Newton, Alfred F.
; Silva, Aline A.S. da
; Santos, Aline B. dos
; Tassi, Aline D.
; Aragão, Allan C.
; Santos, Allan P.M.
; Migotto, Alvaro E.
; Mendes, Amanda C.
; Cunha, Amanda
; Chagas Júnior, Amazonas
; Sousa, Ana A.T. de
; Pavan, Ana C.
; Almeida, Ana C.S.
; Peronti, Ana L.B.G.
; Henriques-Oliveira, Ana L.
; Prudente, Ana L.
; Tourinho, Ana L.
; Pes, Ana M.O.
; Carmignotto, Ana P.
; Wengrat, Ana P.G. da Silva
; Dornellas, Ana P.S.
; Molin, Anamaria Dal
; Puker, Anderson
; Morandini, André C.
; Ferreira, André da S.
; Martins, André L.
; Esteves, André M.
; Fernandes, André S.
; Roza, André S.
; Köhler, Andreas
; Paladini, Andressa
; Andrade, Andrey J. de
; Pinto, Ângelo P.
; Salles, Anna C. de A.
; Gondim, Anne I.
; Amaral, Antonia C.Z.
; Rondón, Antonio A.A.
; Brescovit, Antonio
; Lofego, Antônio C.
; Marques, Antonio C.
; Macedo, Antonio
; Andriolo, Artur
; Henriques, Augusto L.
; Ferreira Júnior, Augusto L.
; Lima, Aurino F. de
; Barros, Ávyla R. de A.
; Brito, Ayrton do R.
; Romera, Bárbara L.V.
; Vasconcelos, Beatriz M.C. de
; Frable, Benjamin W.
; Santos, Bernardo F.
; Ferraz, Bernardo R.
; Rosa, Brunno B.
; Sampaio, Brunno H.L.
; Bellini, Bruno C.
; Clarkson, Bruno
; Oliveira, Bruno G. de
; Corrêa, Caio C.D.
; Martins, Caleb C.
; Castro-Guedes, Camila F. de
; Souto, Camilla
; Bicho, Carla de L.
; Cunha, Carlo M.
; Barboza, Carlos A. de M.
; Lucena, Carlos A.S. de
; Barreto, Carlos
; Santana, Carlos D.C.M. de
; Agne, Carlos E.Q.
; Mielke, Carlos G.C.
; Caetano, Carlos H.S.
; Flechtmann, Carlos H.W.
; Lamas, Carlos J.E.
; Rocha, Carlos
; Mascarenhas, Carolina S.
; Margaría, Cecilia B.
; Waichert, Cecilia
; Digiani, Celina
; Haddad, Célio F.B.
; Azevedo, Celso O.
; Benetti, Cesar J.
; Santos, Charles M.D. dos
; Bartlett, Charles R.
; Bonvicino, Cibele
; Ribeiro-Costa, Cibele S.
; Santos, Cinthya S.G.
; Justino, Cíntia E.L.
; Canedo, Clarissa
; Bonecker, Claudia C.
; Santos, Cláudia P.
; Carvalho, Claudio J.B. de
; Gonçalves, Clayton C.
; Galvão, Cleber
; Costa, Cleide
; Oliveira, Cléo D.C. de
; Schwertner, Cristiano F.
; Andrade, Cristiano L.
; Pereira, Cristiano M.
; Sampaio, Cristiano
; Dias, Cristina de O.
; Lucena, Daercio A. de A.
; Manfio, Daiara
; Amorim, Dalton de S.
; Queiroz, Dalva L. de
; Queiroz, Dalva L. de
; Colpani, Daniara
; Abbate, Daniel
; Aquino, Daniel A.
; Burckhardt, Daniel
; Cavallari, Daniel C.
; Prado, Daniel de C. Schelesky
; Praciano, Daniel L.
; Basílio, Daniel S.
; Bená, Daniela de C.
; Toledo, Daniela G.P. de
; Takiya, Daniela M.
; Fernandes, Daniell R.R.
; Ament, Danilo C.
; Cordeiro, Danilo P.
; Silva, Darliane E.
; Pollock, Darren A.
; Muniz, David B.
; Gibson, David I.
; Nogueira, David S.
; Marques, Dayse W.A.
; Lucatelli, Débora
; Garcia, Deivys M.A.
; Baêta, Délio
; Ferreira, Denise N.M.
; Rueda-Ramírez, Diana
; Fachin, Diego A.
; Souza, Diego de S.
; Rodrigues, Diego F.
; Pádua, Diego G. de
; Barbosa, Diego N.
; Dolibaina, Diego R.
; Amaral, Diogo C.
; Chandler, Donald S.
; Maccagnan, Douglas H.B.
; Caron, Edilson
; Carvalho, Edrielly
; Adriano, Edson A.
; Abreu Júnior, Edson F. de
; Pereira, Edson H.L.
; Viegas, Eduarda F.G.
; Carneiro, Eduardo
; Colley, Eduardo
; Eizirik, Eduardo
; Santos, Eduardo F. dos
; Shimbori, Eduardo M.
; Suárez-Morales, Eduardo
; Arruda, Eliane P. de
; Chiquito, Elisandra A.
; Lima, Élison F.B.
; Castro, Elizeu B. de
; Orlandin, Elton
; Nascimento, Elynton A. do
; Razzolini, Emanuel
; Gama, Emanuel R.R.
; Araujo, Enilma M. de
; Nishiyama, Eric Y.
; Spiessberger, Erich L.
; Santos, Érika C.L. dos
; Contreras, Eugenia F.
; Galati, Eunice A.B.
; Oliveira Junior, Evaldo C. de
; Gallardo, Fabiana
; Hernandes, Fabio A.
; Lansac-Tôha, Fábio A.
; Pitombo, Fabio B.
; Dario, Fabio Di
; Santos, Fábio L. dos
; Mauro, Fabio
; Nascimento, Fabio O. do
; Olmos, Fabio
; Amaral, Fabio R.
; Schunck, Fabio
; Godoi, Fábio S. P. de
; Machado, Fabrizio M.
; Barbo, Fausto E.
; Agrain, Federico A.
; Ribeiro, Felipe B.
; Moreira, Felipe F.F.
; Barbosa, Felipe F.
; Silva, Fenanda S.
; Cavalcanti, Fernanda F.
; Straube, Fernando C.
; Carbayo, Fernando
; Carvalho Filho, Fernando
; Zanella, Fernando C.V.
; Jacinavicius, Fernando de C.
; Farache, Fernando H.A.
; Leivas, Fernando
; Dias, Fernando M.S.
; Mantellato, Fernando
; Vaz-de-Mello, Fernando Z.
; Gudin, Filipe M.
; Albuquerque, Flávio
; Molina, Flavio B.
; Passos, Flávio D.
; Shockley, Floyd W.
; Pinheiro, Francielly F.
; Mello, Francisco de A.G. de
; Nascimento, Francisco E. de L.
; Franco, Francisco L.
; Oliveira, Francisco L. de
; Melo, Francisco T. de V.
; Quijano, Freddy R.B.
; Salles, Frederico F.
; Biffi, Gabriel
; Queiroz, Gabriel C.
; Bizarro, Gabriel L.
; Hrycyna, Gabriela
; Leviski, Gabriela
; Powell, Gareth S.
; Santos, Geane B. dos
; Morse, Geoffrey E.
; Brown, George
; Mattox, George M.T.
; Zimbrão, Geraldo
; Carvalho, Gervásio S.
; Miranda, Gil F.G.
; Moraes, Gilberto J. de
; Lourido, Gilcélia M.
; Neves, Gilmar P.
; Moreira, Gilson R.P.
; Montingelli, Giovanna G.
; Maurício, Giovanni N.
; Marconato, Gláucia
; Lopez, Guilherme E.L.
; Silva, Guilherme L. da
; Muricy, Guilherme
; Brito, Guilherme R.R.
; Garbino, Guilherme S.T.
; Flores, Gustavo E.
; Graciolli, Gustavo
; Libardi, Gustavo S.
; Proctor, Heather C.
; Gil-Santana, Helcio R.
; Varella, Henrique R.
; Escalona, Hermes E.
; Schmitz, Hermes J.
; Rodrigues, Higor D.D.
; Galvão Filho, Hilton de C.
; Quintino, Hingrid Y.S.
; Pinto, Hudson A.
; Rainho, Hugo L.
; Miyahira, Igor C.
; Gonçalves, Igor de S.
; Martins, Inês X.
; Cardoso, Irene A.
; Oliveira, Ismael B. de
; Franz, Ismael
; Fernandes, Itanna O.
; Golfetti, Ivan F.
; S. Campos-Filho, Ivanklin
; Oliveira, Ivo de S.
; Delabie, Jacques H.C.
; Oliveira, Jader de
; Prando, Jadila S.
; Patton, James L.
; Bitencourt, Jamille de A.
; Silva, Janaina M.
; Santos, Jandir C.
; Arruda, Janine O.
; Valderrama, Jefferson S.
; Dalapicolla, Jeronymo
; Oliveira, Jéssica P.
; Hájek, Jiri
; Morselli, João P.
; Narita, João P.
; Martin, João P.I.
; Grazia, Jocélia
; McHugh, Joe
; Cherem, Jorge J.
; Farias Júnior, José A.S.
; Fernandes, Jose A.M.
; Pacheco, José F.
; Birindelli, José L.O.
; Rezende, José M.
; Avendaño, Jose M.
; Duarte, José M. Barbanti
; Ribeiro, José R. Inácio
; Mermudes, José R.M.
; Pujol-Luz, José R.
; Santos, Josenilson R. dos
; Câmara, Josenir T.
; Teixeira, Joyce A.
; Prado, Joyce R. do
; Botero, Juan P.
; Almeida, Julia C.
; Kohler, Julia
; Gonçalves, Julia P.
; Beneti, Julia S.
; Donahue, Julian P.
; Alvim, Juliana
; Almeida, Juliana C.
; Segadilha, Juliana L.
; Wingert, Juliana M.
; Barbosa, Julianna F.
; Ferrer, Juliano
; Santos, Juliano F. dos
; Kuabara, Kamila M.D.
; Nascimento, Karine B.
; Schoeninger, Karine
; Campião, Karla M.
; Soares, Karla
; Zilch, Kássia
; Barão, Kim R.
; Teixeira, Larissa
; Sousa, Laura D. do N.M. de
; Dumas, Leandro L.
; Vieira, Leandro M.
; Azevedo, Leonardo H.G.
; Carvalho, Leonardo S.
; Souza, Leonardo S. de
; Rocha, Leonardo S.G.
; Bernardi, Leopoldo F.O.
; Vieira, Letícia M.
; Johann, Liana
; Salvatierra, Lidianne
; Oliveira, Livia de M.
; Loureiro, Lourdes M.A. El-moor
; Barreto, Luana B.
; Barros, Luana M.
; Lecci, Lucas
; Camargos, Lucas M. de
; Lima, Lucas R.C.
; Almeida, Lucia M.
; Martins, Luciana R.
; Marinoni, Luciane
; Moura, Luciano de A.
; Lima, Luciano
; Naka, Luciano N.
; Miranda, Lucília S.
; Salik, Lucy M.
; Bezerra, Luis E.A.
; Silveira, Luis F.
; Campos, Luiz A.
; Castro, Luiz A.S. de
; Pinho, Luiz C.
; Silveira, Luiz F.L.
; Iniesta, Luiz F.M.
; Tencatt, Luiz F.C.
; Simone, Luiz R.L.
; Malabarba, Luiz R.
; Cruz, Luiza S. da
; Sekerka, Lukas
; Barros, Lurdiana D.
; Santos, Luziany Q.
; Skoracki, Maciej
; Correia, Maira A.
; Uchoa, Manoel A.
; Andrade, Manuella F.G.
; Hermes, Marcel G.
; Miranda, Marcel S.
; Araújo, Marcel S. de
; Monné, Marcela L.
; Labruna, Marcelo B.
; Santis, Marcelo D. de
; Duarte, Marcelo
; Knoff, Marcelo
; Nogueira, Marcelo
; Britto, Marcelo R. de
; Melo, Marcelo R.S. de
; Carvalho, Marcelo R. de
; Tavares, Marcelo T.
; Kitahara, Marcelo V.
; Justo, Marcia C.N.
; Botelho, Marcia J.C.
; Couri, Márcia S.
; Borges-Martins, Márcio
; Felix, Márcio
; Oliveira, Marcio L. de
; Bologna, Marco A.
; Gottschalk, Marco S.
; Tavares, Marcos D.S.
; Lhano, Marcos G.
; Bevilaqua, Marcus
; Santos, Marcus T.T.
; Domingues, Marcus V.
; Sallum, Maria A.M.
; Digiani, María C.
; Santarém, Maria C.A.
; Nascimento, Maria C. do
; Becerril, María de los A.M.
; Santos, Maria E.A. dos
; Passos, Maria I. da S. dos
; Felippe-Bauer, Maria L.
; Cherman, Mariana A.
; Terossi, Mariana
; Bartz, Marie L.C.
; Barbosa, Marina F. de C.
; Loeb, Marina V.
; Cohn-Haft, Mario
; Cupello, Mario
; Martins, Marlúcia B.
; Christofersen, Martin L.
; Bento, Matheus
; Rocha, Matheus dos S.
; Martins, Maurício L.
; Segura, Melissa O.
; Cardenas, Melissa Q.
; Duarte, Mércia E.
; Ivie, Michael A.
; Mincarone, Michael M.
; Borges, Michela
; Monné, Miguel A.
; Casagrande, Mirna M.
; Fernandez, Monica A.
; Piovesan, Mônica
; Menezes, Naércio A.
; Benaim, Natalia P.
; Reategui, Natália S.
; Pedro, Natan C.
; Pecly, Nathalia H.
; Ferreira Júnior, Nelson
; Silva Júnior, Nelson J. da
; Perioto, Nelson W.
; Hamada, Neusa
; Degallier, Nicolas
; Chao, Ning L.
; Ferla, Noeli J.
; Mielke, Olaf H.H.
; Evangelista, Olivia
; Shibatta, Oscar A.
; Oliveira, Otto M.P.
; Albornoz, Pablo C.L.
; Dellapé, Pablo M.
; Gonçalves, Pablo R.
; Shimabukuro, Paloma H.F.
; Grossi, Paschoal
; Rodrigues, Patrícia E. da S.
; Lima, Patricia O.V.
; Velazco, Paul
; Santos, Paula B. dos
; Araújo, Paula B.
; Silva, Paula K.R.
; Riccardi, Paula R.
; Garcia, Paulo C. de A.
; Passos, Paulo G.H.
; Corgosinho, Paulo H.C.
; Lucinda, Paulo
; Costa, Paulo M.S.
; Alves, Paulo P.
; Roth, Paulo R. de O.
; Coelho, Paulo R.S.
; Duarte, Paulo R.M.
; Carvalho, Pedro F. de
; Gnaspini, Pedro
; Souza-Dias, Pedro G.B.
; Linardi, Pedro M.
; Bartholomay, Pedro R.
; Demite, Peterson R.
; Bulirsch, Petr
; Boll, Piter K.
; Pereira, Rachel M.M.
; Silva, Rafael A.P.F.
; Moura, Rafael B. de
; Boldrini, Rafael
; Silva, Rafaela A. da
; Falaschi, Rafaela L.
; Cordeiro, Ralf T.S.
; Mello, Ramon J.C.L.
; Singer, Randal A.
; Querino, Ranyse B.
; Heleodoro, Raphael A.
; Castilho, Raphael de C.
; Constantino, Reginaldo
; Guedes, Reinaldo C.
; Carrenho, Renan
; Gomes, Renata S.
; Gregorin, Renato
; Machado, Renato J.P.
; Bérnils, Renato S.
; Capellari, Renato S.
; Silva, Ricardo B.
; Kawada, Ricardo
; Dias, Ricardo M.
; Siewert, Ricardo
; Brugnera, Ricaro
; Leschen, Richard A.B.
; Constantin, Robert
; Robbins, Robert
; Pinto, Roberta R.
; Reis, Roberto E. dos
; Ramos, Robson T. da C.
; Cavichioli, Rodney R.
; Barros, Rodolfo C. de
; Caires, Rodrigo A.
; Salvador, Rodrigo B.
; Marques, Rodrigo C.
; Araújo, Rodrigo C.
; Araujo, Rodrigo de O.
; Dios, Rodrigo de V.P.
; Johnsson, Rodrigo
; Feitosa, Rodrigo M.
; Hutchings, Roger W.
; Lara, Rogéria I.R.
; Rossi, Rogério V.
; Gerstmeier, Roland
; Ochoa, Ronald
; Hutchings, Rosa S.G.
; Ale-Rocha, Rosaly
; Rocha, Rosana M. da
; Tidon, Rosana
; Brito, Rosangela
; Pellens, Roseli
; Santos, Sabrina R. dos
; Santos, Sandra D. dos
; Paiva, Sandra V.
; Santos, Sandro
; Oliveira, Sarah S. de
; Costa, Sávio C.
; Gardner, Scott L.
; Leal, Sebastián A. Muñoz
; Aloquio, Sergio
; Bonecker, Sergio L.C.
; Bueno, Sergio L. de S.
; Almeida, Sérgio M. de
; Stampar, Sérgio N.
; Andena, Sérgio R.
; Posso, Sergio R.
; Lima, Sheila P.
; Gadelha, Sian de S.
; Thiengo, Silvana C.
; Cohen, Simone C.
; Brandão, Simone N.
; Rosa, Simone P.
; Ribeiro, Síria L.B.
; Letana, Sócrates D.
; Santos, Sonia B. dos
; Andrade, Sonia C.S.
; Dávila, Stephane
; Vaz, Stéphanie
; Peck, Stewart B.
; Christo, Susete W.
; Cunha, Suzan B.Z.
; Gomes, Suzete R.
; Duarte, Tácio
; Madeira-Ott, Taís
; Marques, Taísa
; Roell, Talita
; Lima, Tarcilla C. de
; Sepulveda, Tatiana A.
; Maria, Tatiana F.
; Ruschel, Tatiana P.
; Rodrigues, Thaiana
; Marinho, Thais A.
; Almeida, Thaís M. de
; Miranda, Thaís P.
; Freitas, Thales R.O.
; Pereira, Thalles P.L.
; Zacca, Thamara
; Pacheco, Thaynara L.
; Martins, Thiago F.
; Alvarenga, Thiago M.
; Carvalho, Thiago R. de
; Polizei, Thiago T.S.
; McElrath, Thomas C.
; Henry, Thomas
; Pikart, Tiago G.
; Porto, Tiago J.
; Krolow, Tiago K.
; Carvalho, Tiago P.
; Lotufo, Tito M. da C.
; Caramaschi, Ulisses
; Pinheiro, Ulisses dos S.
; Pardiñas, Ulyses F.J.
; Maia, Valéria C.
; Tavares, Valeria
; Costa, Valmir A.
; Amaral, Vanessa S. do
; Silva, Vera C.
; Wolff, Vera R. dos S.
; Slobodian, Verônica
; Silva, Vinícius B. da
; Espíndola, Vinicius C.
; Costa-Silva, Vinicius da
; Bertaco, Vinicius de A.
; Padula, Vinícius
; Ferreira, Vinicius S.
; Silva, Vitor C.P. da
; Piacentini, Vítor de Q.
; Sandoval-Gómez, Vivian E.
; Trevine, Vivian
; Sousa, Viviane R.
; Sant’Anna, Vivianne B. de
; Mathis, Wayne N.
; Souza, Wesley de O.
; Colombo, Wesley D.
; Tomaszewska, Wioletta
; Wosiacki, Wolmar B.
; Ovando, Ximena M.C.
; Leite, Yuri L.R.
.
ABSTRACT The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classifications. In this context, the Brazilian megadiverse fauna is no exception, and the Catálogo Taxonômico da Fauna do Brasil (CTFB) (http://fauna.jbrj.gov.br/), made public in 2015, represents a database on biodiversity anchored on a list of valid and expertly recognized scientific names of animals in Brazil. The CTFB is updated in near real time by a team of more than 800 specialists. By January 1, 2024, the CTFB compiled 133,691 nominal species, with 125,138 that were considered valid. Most of the valid species were arthropods (82.3%, with more than 102,000 species) and chordates (7.69%, with over 11,000 species). These taxa were followed by a cluster composed of Mollusca (3,567 species), Platyhelminthes (2,292 species), Annelida (1,833 species), and Nematoda (1,447 species). All remaining groups had less than 1,000 species reported in Brazil, with Cnidaria (831 species), Porifera (628 species), Rotifera (606 species), and Bryozoa (520 species) representing those with more than 500 species. Analysis of the CTFB database can facilitate and direct efforts towards the discovery of new species in Brazil, but it is also fundamental in providing the best available list of valid nominal species to users, including those in science, health, conservation efforts, and any initiative involving animals. The importance of the CTFB is evidenced by the elevated number of citations in the scientific literature in diverse areas of biology, law, anthropology, education, forensic science, and veterinary science, among others. publications problem uptodate up date classifications context exception (CTFB http//fauna.jbrj.gov.br/, httpfaunajbrjgovbr http //fauna.jbrj.gov.br/ , jbrj gov br (http://fauna.jbrj.gov.br/) 2015 Brazil 80 specialists 1 2024 133691 133 691 133,69 125138 125 138 125,13 82.3%, 823 82 3 (82.3% 102000 102 000 102,00 7.69%, 769 7 69 (7.69% 11000 11 11,00 . 3,567 3567 567 (3,56 2,292 2292 2 292 (2,29 1,833 1833 833 (1,83 1,447 1447 447 (1,44 1000 1,00 831 (83 628 (62 606 (60 520 (52 50 users science health biology law anthropology education others http//fauna.jbrj.gov.br/ faunajbrjgovbr //fauna.jbrj.gov.br (http://fauna.jbrj.gov.br/ 201 8 202 13369 13 133,6 12513 12 125,1 82.3% (82.3 10200 10 00 102,0 7.69% 76 6 (7.69 1100 11,0 3,56 356 56 (3,5 2,29 229 29 (2,2 1,83 183 83 (1,8 1,44 144 44 (1,4 100 1,0 (8 62 (6 60 52 (5 5 http//fauna.jbrj.gov.br (http://fauna.jbrj.gov.br 20 1336 133, 1251 125, 82.3 (82. 1020 0 102, 7.69 (7.6 110 11, 3,5 35 (3, 2,2 22 (2, 1,8 18 (1, 1,4 14 4 ( 82. (82 7.6 (7. 3, (3 2, (2 (1 7. (7
5.
Colorimetry and chemical properties of thermally modified Parkia pendula and Simarouba amara wood
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SOUZA, Leonardo Vinícius de
; STANGERLIN, Diego Martins
; MELO, Rafael Rodolfo de
; LENGOWSKI, Elaine Cristina
; BONFATTI JÚNIOR, Eraldo Antonio
; VASCONCELOS, Leonardo Gomes de
; PIMENTA, Alexandre Santos
.
RESUMO A modificação térmica da madeira é um processo que altera sua composição química, visando melhorar propriedades tecnológicas como estabilidade dimensional, redução do teor de umidade de equilíbrio, homogeneidade ou cor. Neste contexto, este estudo teve como objetivo avaliar a colorimetria e as propriedades químicas da madeira de Parkia pendula (angelim-saia) e Simarouba amara (marupá) modificada termicamente por diferentes métodos. Foram avaliados três tratamentos: T1 (pré-tratamento em estufa por uma hora a 120 °C e tratamento em estufa a 180 °C por três horas); T2 (pré-tratamento em autoclave a 125 °C por três horas sob 1,2 kgf cm-2 e tratamento em estufa a 180 °C por três horas); T3 (sem pré-tratamento, com tratamento da amostra em óleo vegetal). A madeira termicamente modificada foi avaliada em relação à madeira não tratada quanto à composição química estrutural (extrativos, lignina, holocelulose e teor de cinzas), parâmetros colorimétricos definidos através do sistema CIELAB (Commission Internationale de l´Eclairage) e variação total de cores. Detectamos um aumento significativo no teor de extrativos e uma diminuição no teor de holocelulose e lignina em T3 para ambas espécies, o que pode ser explicado pela impregnação de óleo nas amostras de madeira. A modificação térmica provocou o escurecimento superficial da madeira de ambas espécies, que foi mais pronunciado em P. pendula. Apesar da alteração colorimétrica, quimicamente não houve prejuízos para as madeiras. dimensional equilíbrio cor contexto angelimsaia angelim saia (angelim-saia marupá (marupá métodos tratamentos T prétratamento pré 12 C 18 horas) 1 2 1, cm2 cm cm- sem prétratamento, tratamento, pré-tratamento vegetal. vegetal . vegetal) extrativos, (extrativos cinzas, cinzas , cinzas) Commission l´Eclairage lEclairage l Eclairage cores espécies P colorimétrica madeiras
ABSTRACT The thermal modification of wood is a process that alters its chemical composition, aiming to improve technological properties such as dimensional stability, reduction of equilibrium moisture content, homogeneity, or color. In this context, this study aimed to evaluate the colorimetry and chemical properties of the wood of Parkia pendula (angelim-saia) and Simarouba amara (marupá) that was thermally modified by different methods. Three treatments were evaluated: T1 (pre-treatment in an oven for one hour at 120 °C and treatment in an oven at 180 °C for three hours); T2 (pre-treatment in an autoclave at 125 °C for three hours under 1.2 kgf cm-2 and treatment in an oven at 180 °C for three hours); and T3 (without pre-treatment, with sample treatment in vegetable oil). The thermally modified wood was evaluated in relation to untreated wood for structural chemical composition (extractives, lignin, holocellulose and ash content), colorimetric parameters defined through the CIELAB (Commission Internationale de l´Eclairage) system and total color variation. We detected a significant increase in extractives content and a decrease in holocellulose and lignin content in T3 for both species, which can be explained by the impregnation of oil in the wood samples. The thermal modification caused the surface darkening of the wood of both species, which was more pronounced in P. pendula. Despite the colorimetric change, there was no chemical damage to the wood. stability homogeneity context angelimsaia angelim saia (angelim-saia marupá (marupá methods T pretreatment pre 12 C 18 hours) 1 2 1. cm2 cm cm- without pretreatment, treatment, pre-treatment oil. . oil) extractives, (extractives , content) Commission l´Eclairage lEclairage l Eclairage variation species samples P change
6.
Silicates as alternative pretreatment for cellulose pulp to obtain nanofibrils for application in biodegradable packaging: a technical review packaging
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Mascarenhas, Adriano Reis Prazeres
; Scatolino, Mário Vanoli
; Lago, Rafael Carvalho do
; Medeiros, Dayane Targino
; Batista, Felipe Gomes
; Setter, Carine
; Melo, Rafael Rodolfo de
; Martins, Maria Alice
; Tonoli, Gustavo Henrique Denzin
.
ABSTRACT Background: The production of cellulose microfibrils/nanofibrils (CMF/CNF) has attracted increasing attention in recent decades due to their excellent barrier, mechanical, and surface chemistry properties. However, large-scale industrial production of CMF/CNF has been a major challenge due to their high energy consumption, limiting their application. In this context, in recent years many studies have focused on developing pre-treatments designed to facilitate the fibrillation of CMF/CNF by reducing energy consumption during their production. This review highlights the latest advances in the use of silicates as chemical pre-treatments for CMF/CNF production, covering the main aspects related to the effects of chemical modification on the production and the properties of materials for application in biodegradable packaging. Results: Energy consumption reductions of up to 30% were achieved by pretreating cellulose pulps using silicates. In addition, the pre-treatments resulted in smaller CMF/CNF diameters and greater individualization of the nanofibrils. Studies evaluating the thermal stability, hydrophobicity, mechanical properties, and porosity of CMF/CNF pre-treated with silicates have reported promising results. The application of CMF/CNF pretreated with calcium and magnesium silicates in cardboard coating resulted in packaging with low water vapor permeability and high ductility. Conclusion: Silicates interact well with cellulose surfaces, making them a promising material for the chemical pre-treatment of CMF/CNF. Furthermore, the modification by silicates could be an interesting strategy for expanding the use of CMF/CNF in the development of new products. Background microfibrilsnanofibrils microfibrils nanofibrils CMFCNF CMF CNF (CMF/CNF barrier However largescale large scale context pretreatments pre treatments Results 30 addition stability hydrophobicity treated results ductility Conclusion surfaces pretreatment treatment Furthermore products 3
7.
Mini-Rectangular Kiln to Produce Charcoal and Wood Vinegar MiniRectangular Mini Rectangular
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Abstract This research aimed to evaluate the production of charcoal and wood vinegar in a mini-rectangular kiln equipped with a condenser and vertical smoke burner. The kiln had a chimney, a condenser and a vertical smoke burner. The logs were 0.90 m long and had characterized. Ten carbonization runs were conducted to evaluate the kiln’s performance, determining the gravimetric yields in charcoal, wood vinegar, and gases. The carbonization process took three days to conclude and four days to cool the charcoal. The results showed that the average yields for charcoal, wood vinegar, and gases were 34.0, 31.2, and 34.8%, respectively. The charcoal produced, despite the use of moderate-density wood, demonstrated favorable characteristics. The moisture content, ash content, volatile materials, and higher calorific values all fell within the ideal ranges. This, coupled with a good yield, confirms the technical viability of the system as an alternative for small producers. minirectangular mini rectangular burner chimney 090 0 90 0.9 characterized kilns s performance 340 34 34.0 312 31 2 31.2 348 8 34.8% respectively produced moderatedensity moderate density characteristics content materials ranges yield producers 09 9 0. 3 34. 31. 34.8
8.
From coconut waste to the production of cementitious composites as an alternative for civil construction
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Silva, Fernanda Monique da
; Scatolino, Mario Vanoli
; Paula, Edgley Alves de Oliveira
; Almeida, Vanessa Gentil de Oliveira
; Albuquerque, Felipe Bento de
; Vieira, Ricardo Alan da Silva
; Souza, Joalis Barbalho de
; Pedrosa, Talita Dantas
; Rodolfo Junior, Francisco
; Melo, Rafael Rodolfo de
.
ABSTRACT Economic development based on cleaner industrial technologies has been increasingly studied in recent years. Cementitious composites reinforced with lignocellulosic fibers can be a sustainable alternative for use in engineering. The study aimed to evaluate the technological properties of cementitious composites produced from natural and industrial coconut fiber to compare the reinforcement with wood particles. Physical tests (density, water absorption, and thickness swelling) and mechanical tests (static bending) were carried out in four treatments, which varied the fiber and cement contents. It was found that treatment with natural coconut fiber had the lowest density value, 0.59 g/cm3, and treatment with industrial coconut fiber had the lowest water absorption value for the times and times of 2 and 24 h, 0.19, and 0.38%, respectively, and the treatment with wood particles, the highest values of modulus of elasticity and rupture, 1,897 MPa and 2.44 MPa. The study of the use of lignocellulosic materials as protection in cementitious composites is essential for applications in building constructions to reduce the environmental impacts generated by the generation of waste and use of non-renewable materials and to promote sustainable development. years engineering particles density, (density swelling static bending treatments contents 059 0 59 0.5 gcm3 gcm g cm3 cm g/cm3 h 019 19 0.19 038 38 0.38% respectively rupture 1897 1 897 1,89 244 44 2.4 nonrenewable non renewable 05 5 0. g/cm 01 0.1 03 3 0.38 189 89 1,8 4 2. 0.3 18 8 1,
9.
Durability and resistance of eco-friendly particleboards produced from agroforestry residues ecofriendly eco friendly
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Mensah, Prosper
; Govina, James
; Owusu-Asante, Judith Odei
; Seidu, Haruna
; Rodolfo Junior, Francisco
; Paula, Edgley Alves de Oliviera
; Pedrosa, Talita Dantas
; Melo, Rafael Rodolfo de
.
Abstract The aim to evaluate the raw material (agroforestry residues) for particleboard manufacture from the: pseudostem of Musa paradisiaca; the stem and pods of Theobroma cacao; and the sawdust of Ceiba pentandra. The particleboards produced from these cellulosic residues are mixed with cassava starch’s natural adhesive and urea formaldehyde’s synthetic adhesive. The results indicate that lignin, α-cellulose, hemicellulose, and extractives ranged from 6.2–19.0%, 41.4–50.2%, 24.4–31.5%, and 6.8–18.8% respectively and they were significantly different from each other. Additionally, tannins, alkaloids, saponins, flavonoids, phenols, glycosides, and sterols were the phytochemicals present in biomass materials in different quantities. Also, carbon, oxygen, nitrogen, and boron were the elementals significantly present in the manufactured particleboards in the range of 35.3–52.8, 30.2–43.0, 4.2–24.0, and 3.2–9.9 percentage concentration respectively. As for the mechanical properties, it was verified that the cellulose content influenced 96.5% of the variability of the modulus of rupture (MOR) values. Understanding the distribution, functional properties, and impact of biomass organic, phytochemicals and elemental constitutions is an impetus to the improvement of processes with higher retention of these constitutions in the utilization of agroforest residues in the particleboard industry. These chemical compositions of the residues under study contributed largely to the characteristics of the manufactured particleboards. agroforestry paradisiaca cacao pentandra starchs starch s formaldehydes formaldehyde lignin αcellulose, αcellulose α cellulose, α-cellulose hemicellulose 62190 6 2 19 0 6.2–19.0% 414502 41 4 50 41.4–50.2% 244315 24 31 5 24.4–31.5% 68188 8 18 6.8–18.8 other Additionally tannins alkaloids saponins flavonoids phenols glycosides quantities Also carbon oxygen nitrogen 353528 35 3 52 35.3–52.8 302430 30 43 30.2–43.0 42240 4.2–24.0 3299 9 3.2–9. properties 965 96 96.5 MOR (MOR values distribution organic industry 6219 1 6.2–19.0 41450 41.4–50.2 24431 24.4–31.5 6818 6.8–18. 35352 35.3–52. 30243 30.2–43. 4224 4.2–24. 329 3.2–9 96. 621 6.2–19. 4145 41.4–50. 2443 24.4–31. 681 6.8–18 3535 35.3–52 3024 30.2–43 422 4.2–24 32 3.2– 62 6.2–19 414 41.4–50 244 24.4–31 68 6.8–1 353 35.3–5 302 30.2–4 42 4.2–2 3.2 6.2–1 41.4–5 24.4–3 6.8– 35.3– 30.2– 4.2– 3. 6.2– 41.4– 24.4– 6.8 35.3 30.2 4.2 6.2 41.4 24.4 6. 35. 30. 4. 41. 24.
10.
Efeito da temperatura e pressão nas propriedades da liga de titânio Ti-6Aℓ-4V produzida a partir da metalurgia do pó Ti6Aℓ4V TiAℓV Ti 6Aℓ 4V Aℓ V
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Silva Vieira, Ricardo Alan da
; Fonseca, Erbenia Taciane Fernandes da
; Silva Júnior, Manoel Quirino da
; Oliveira Paula, Edgley Alves de
; Silva, Fernanda Monique da
; Albuquerque, Felipe Bento de
; Souza, Joalis Barbalho de
; Rusch, Fernando
; Scatolino, Mário Vanoli
; Melo, Rafael Rodolfo de
.
RESUMO Foram caracterizadas micro estruturalmente e mecanicamente a liga Ti-6Aℓ-4V obtida através da metalurgia do pó em atmosfera não controlada variando os parâmetros de sinterização. As amostras foram compactadas em uma prensa uniaxial à 874 MPa, 999 MPa e 1124 MPa, e sinterizadas sem atmosfera protetora ou vácuo, nas temperaturas de 675 °C, 750 °C e 850 °C. Ao sinterizar o material, houve influência dos óxidos nos resultados devido à alta afinidade que o titânio tem por elementos intersticiais, promovendo um aumento na densidade e elevados valores de dureza. A partir dos resultados verificou-se que o tratamento realizado na pressão de 1124 MPa e temperatura de 750 °C foi o que apontou a maior dureza na fase beta (β), sendo o valor de 1165,1 HV. Na fase alfa (α), o maior valor foi de 1321,3 HV, apresentado pelo tratamento realizado na pressão de 999 MPa e temperatura de 850 °C. Os elevados valores na dureza observados na liga estão associados ao reforço promovido pela dissolução átomos de Fe. Materiais com elevada dureza possuem uma vasta aplicação nas indústrias aeroespaciais e biomédicas, que buscam sempre por melhores resultados de resistência mecânica, aumentando assim a vida útil e a aplicabilidades de seus produtos. Ti6Aℓ4V TiAℓV Ti 6Aℓ 4V Aℓ V sinterização 87 99 112 vácuo 67 C 75 85 material intersticiais verificouse verificou se β, β , (β) 11651 1165 1 1165, HV α, α (α) 13213 1321 3 1321, Fe biomédicas mecânica produtos 8 9 11 6 7 (β 116 (α 132 13
ABSTRACT Were characterized microstructurally and mechanically the Ti-6Aℓ-4V alloy obtained through powder metallurgy in an uncontrolled atmosphere, varying the sintering parameters, arose. The samples were compacted in a uniaxial press at 874 MPa, 999 MPa, and 1124 MPa, and sintered without a protective atmosphere or vacuum, at 675 °C, 750 °C, and 850 °C. When sintering the material, the oxides influenced the results due to titanium’s high affinity for interstitial elements, promoting increased density and high hardness values. Based on the results, the treatment carried out at a pressure of 1124 MPa and a temperature of 750 °C showed the highest hardness in the beta phase (β), with a value of 1165.1 HV. In the alpha phase (α), the highest value was 1321.3 HV, presented by the treatment performed at a pressure of 999 MPa and a temperature of 850 °C. The high hardness values observed in the alloy are associated with the reinforcement promoted by the dissolution of Fe atoms. Materials with high hardness values use in the aerospace and biomedical industries, which always look for better mechanical resistance results, thus increasing their products’ useful life and applicability. Ti6Aℓ4V TiAℓV Ti 6Aℓ 4V Aℓ V parameters arose 87 99 112 vacuum 67 C 75 85 material titaniums titanium s elements β, β , (β) 11651 1165 1 1165. HV α, α (α) 13213 1321 3 1321. atoms industries products applicability 8 9 11 6 7 (β 116 (α 132 13
11.
Prediction of the basic density of tropical woods by near-infrared spectroscopy nearinfrared near infrared
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Medeiros, Dayane Targino de
; Melo, Rafael Rodolfo de
; Cademartori, Pedro Henrique Gonzalez de
; Batista, Felipe Gomes
; Mascarenhas, Adriano Reis Prazeres
; Scatolino, Mário Vanoli
; Hein, Paulo Ricardo Gherardi
.
ABSTRACT Background: Determining the basic density of the wood is usually defined as a simple process, but it requires caution and the operator’s skill to avoid errors in the analysis. In addition, it involves sample preparation and time to saturate the wood until obtaining the dry sample mass. The development of alternative measurement techniques could reduce the time to obtain the results and provide reliable values. Therefore, this study aimed to develop multivariate models to estimate the basic density of native woods using near-infrared spectra (NIR). Basic densities were determined by the water immersion method, and the values were associated with NIR signatures. Spectra were directly collected on the wood transversal and radial faces with an integrating sphere. Partial least squares regression (PLS-R) was calibrated and validated to estimate basic density based on spectral signatures. Results: In the cross-validation and prediction of the models, the results were promising. The coefficients of determination varied from 0.87 to 0.93 with a standard error of 0.01 %. The partial least squares discriminant analysis (PLS-DA) efficiently classified the wood species. The ratio of performance to deviation obtained satisfactory values, a minimum of 2.81 and a maximum of 4.20. Conclusion: The statistical parameters of the models based on NIR spectra showed potential for density measurements in floors, furniture, and solid wood products. Background process operators operator s addition mass Therefore nearinfrared near infrared NIR. . (NIR) method signatures sphere PLSR PLS R (PLS-R Results crossvalidation cross validation promising 087 0 87 0.8 093 93 0.9 001 01 0.0 % PLSDA DA (PLS-DA species 281 2 81 2.8 420 4 20 4.20 Conclusion floors furniture products (NIR 08 8 0. 09 9 00 28 2. 42 4.2 4.
12.
Improvement of the properties of hardboard with heat treatment application
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Costa, Laíze Jorge da
; Paula, Edgley Alves de Oliveira
; Melo, Rafael Rodolfo de
; Scatolino, Mario Vanoli
; Albuquerque, Felipe Bento de
; Oliveira, Ramona Rodrigues Amaro de
; Souza, Joana Alice Galdino de
; Silva, Ana Karla Vieira da
; Santos, Márcia Ellen Chagas dos
; Rodolfo Junior, Francisco
.
ABSTRACT The attempt to face the limitations of wood-based materials, especially concerning the relationship with water, is still a considerable gap in research on this subject. The present work proposes the accomplishment of thermal treatment in fiberboard-type hardboard, using different temperatures and times, to evaluate the effect on the physical-mechanical properties. The parameters of the heat treatment were temperatures of 120 and 160 °C and times of 20 and 40 min. The hardboards were individually heat treated in a kiln. The characterization was performed from physical tests such as bulk density, moisture content, water absorption (2 and 24 h), thickness swelling (2 and 24 h); and mechanical properties of flexural strength. The treatment with a temperature of 160 °C for 40 min showed the lowest values of water absorption in 24 h (34%). Thickness swelling was lower compared to control, for all the treatments applied. Regarding flexural strength, the treatment that adopted the 160 °C for 20 min showed the highest MOR value (26.3 MPa). In general, the performance of heat treatments positively influenced the physical and mechanical properties of the hardboards, being an interesting alternative in the development of products for applications in internal environments. woodbased wood based materials subject fiberboardtype fiberboard type hardboard physicalmechanical 12 16 C 2 4 kiln density content ( h, , h) strength 34%. 34 34% . (34%) control applied 26.3 263 26 3 (26. MPa. MPa MPa) general environments 1 (34% 26. (26 (34 (3
13.
Effects of termal treatment on the physical properties of Buchenavia sp. (branquilho) wood
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Vollbrecht, Laysa Teles
; Mascarenhas, Adriano Reis Prazeres
; Melo, Rafael Rodolfo de
; Lima, Maúcha Fernanda de Mota
; Soteil, Ricardo Pereira
; Pimenta, Alexandre Santos
.
Resumo Objetivou-se avaliar o efeito do tratamento térmico nas propriedades físicas da madeira de Buchenavia sp. Os tratamentos térmicos foram feitos em temperaturas de 180 °C e 200 °C durante 2 h. Avaliou-se a densidade aparente (AD), densidade básica (BD), porosidade (Ф), perda de massa, contração longitudinal (LS), radial (RS), tangencial (TS) e volumétrica (VS) e fator anisotrópico (AF). Os menores valores de densidade básica (0,67 g cm -3 ), densidade aparente (0,77 g cm -3 ) e porosidade (43,3%) foram observados para a madeira tratada em temperatura de 200 °C. As perdas de massa foram crescentes com o aumento da temperatura e os maiores valores foram observados na condição de 200 °C (9,3%). A LS e o AF não foram afetados pelos tratamentos térmicos. Os valores médios para RS (3,1%), TS (5,1%) e VS (9,1%) foram reduzidos após a realização dos tratamentos térmicos nas temperaturas de 180°C e 200 °C, que não diferiram entre si. Os tratamentos térmicos foram capazes de diminuir a instabilidade dimensional da madeira de Buchenavia sp. Os tratamentos térmicos potencializam o uso de madeiras da Amazônia de menor prestígio no mercado no contexto da construção civil.
Abstract This work aimed to evaluate the effect of heat treatment on the physical properties of wood from Buchenavia sp. The heat treatments were carried out at temperatures of 180 °C and 200 °C for 2 h. Apparent density (AD), basic density (BD), porosity (Ф), mass loss, longitudinal (LS), radial (RS), tangential (TS) and volumetric (VS) shrinkages and anisotropic factor (AF) were determined. The lowest values of basic density (0.67 g cm-3), apparent density (0.77 gcm-3), and porosity (43.3%) were observed for the wood treated at a temperature of 200 °C. Mass losses increased with increasing temperature and the highest values were observed under the condition of 200 °C (9.3%). The LS and AF was not affected by heat treatments. The mean values for RS (3.1%), TS (5.1%), and VS (9.1%) were reduced after the performance of heat treatments at temperatures of 180°C and 200°C, which did not differ from each other. The thermal treatments were able to reduce the dimensional instability of Buchenavia sp. Thermal treatments enhance the use of less prestigious Amazonian woods in the civil construction market.
https://doi.org/10.1590/s1678-86212022000100580
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14.
Resistance of acetylated Jacaranda copaia wood to termites and decaying fungi attack
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BAUFLEUR, Andressa Midori Yamauchi
; STANGERLIN, Diego Martins
; GOUVEIA, Fernando Nunes
; SILVA, Anna Sofya Vanessa Silvério da
; OLIVEIRA, José Roberto Victor de
; SILVEIRA, Marcelo Fontana da
; PIMENTA, Alexandre Santos
; MELO, Rafael Rodolfo de
.
RESUMO A durabilidade natural da madeira é essencial para a definição de seu uso, e essa propriedade pode ser potencializada com o tratamento químico adequado da madeira. Assim, o objetivo deste trabalho foi avaliar a resistência da madeira de Jacaranda copaia modificada quimicamente por acetilação a cupins e fungos apodrecedores. Cinco tratamentos experimentais foram avaliados: acetilação por 2, 4, 6 e 8 horas e um controle (não acetilado). A acetilação foi realizada por imersão das amostras de madeira em anidrido acético a 90°C. Amostras acetiladas e controle foram submetidas à ação de cupins xilófagos (Nasutitermes sp.) e fungos apodrecedores (Gloeophyllum trabeum e Trametes versicolor). O processo de acetilação aumentou significativamente a resistência da madeira de Jacaranda copaia ao ataque dos organismos xilófagos. Não houve perda de massa após exposição aos cupins da madeira em nenhum dos tratamentos de acetilação, enquanto na madeira controle a perda de massa foi de 9,5%. Em relação aos fungos em decomposição, ocorreu perda de massa em todos os tratamentos. Os tratamentos químicos mais eficientes foram os de acetilação por 6 e 8 horas, elevando a classe de resistência da madeira de Jacaranda copaia para altamente resistente.
ABSTRACT The natural durability of the wood is essential for the definition of its use, and this property can be enhanced with the proper chemical treatment of the wood. Thus, the objective of this study was to evaluate the resistance to termites and decay fungi of Jacaranda copaia wood chemically modified through acetylation. Five experimental treatments were assessed: acetylation for 2, 4, 6 and 8 hours and a control (non-acetylated). The acetylation was carried out by immersing wood samples in acetic anhydride at 90 °C. Acetylated and control samples were subjected to the action of xylophagous termites (Nasutitermes sp.) and decaying fungi (Gloeophyllum trabeum and Trametes versicolor). The acetylation process significantly increased the resistance of Jacaranda copaia wood to the attack of the xylophagous organisms. There was no mass loss after exposure to termites of the wood in any of the acetylation treatments, while in the control wood, mass loss was 9.5%. Regarding the decaying fungi, mass loss occurred in all treatments. Acetylation for 6 and 8 hours were the most efficient chemical treatments, increasing the resistance class of the Jacaranda copaia wood to highly resistant.
15.
Production of kraft pulp from Ochroma pyramidale wood
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SILVA, Rafaeli Valério da
; CARDOSO, Gabriel Valim
; SILVA JÚNIOR, Francides Gomes da
; STANGERLIN, Diego Martins
; MELO, Rafael Rodolfo de
; COELHO, Marina Ulian
; PIMENTA, Alexandre Santos
.
RESUMO O Brasil se destaca no cenário internacional em relação a produção de celulose de fibra curta. Apesar da grande biodiversidade brasileira, essa produção está baseada em clones de espécies exóticas de Eucalyptus. Nesse contexto, pode haver grande potencial na avaliação de novas fontes de fibras da flora brasileira, incluindo a região amazônica. O presente estudo teve como objetivo avaliar o potencial tecnológico da madeira de Ochroma pyramidale (Malvaceae) para produção de celulose kraft. Indivíduos de quatro anos de idade foram colhidos em um plantio comercial para produção de serrados no Estado do Mato Grosso. Determinamos as propriedades químicas (teores de holocelulose, lignina Klason, lignina solúvel, extrativos e cinzas), físicas (massa específica e porosidade) e morfologia de fibras (comprimento e largura de fibras, diâmetro do lume, espessura e fração de parede, coeficiente de flexibilidade, índice de enfeltramento e de Runkel) da madeira. Na polpação kraft a carga alcalina aplicada variou entre 10 e 24%, com intervalo de 2%. A madeira de Ochroma pyramidale apresentou características favoráveis à produção de polpa celulósica, como dimensões apropriadas das fibras e baixos teores de lignina, extrativos e cinzas. Os teores de álcali ativo residual e pH do licor negro apresentaram relação crescente com a carga alcalina aplicada nos processos de polpação. O acréscimo da carga alcalina reduziu o rendimento em polpação, número kappa, teor de rejeitos e aumentou o teor de ácidos hexenurônicos.
ABSTRACT Brazil stands out in the international scenario in the production of short-fiber pulp. Despite the great Brazilian biodiversity, that production is based on exotic Eucalyptus clones. In this sense, there may be great potential in the assessment of new sources of fibers from the Brazilian flora, including the Amazon. The present study aimed to assess the technical potential of the wood of Ochroma pyramidale (Malvaceae) for the production of kraft pulp. Four-year-old trees were harvested from a commercial forest for lumber production in Mato Grosso state (Brazil). We determined the wood’s chemical compositions (holocellulose, Klason lignin, soluble lignin, extractives and ash contents), physical properties (density and porosity), and fiber morphology (fiber length, width and thickness, lumen diameter, wall fraction, coefficient of flexibility, and slenderness and Runkel ratios). The wood was subjected to pulping with an effective alkali charge ranging from 10 to 24%, with intervals of 2%. Ochroma pyramidale wood presented characteristics favorable to the production of cellulosic pulp, such as appropriate fiber dimensions and low lignin, extractives, and ash content. The amount of residual active alkali and pH of the black liquor were positively related to the increase of the alkali charge employed in the pulping process. The increase of alkali charge decreased the pulp yield, kappa number and waste content, and increased the hexenuronic acid concentration.
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