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Your search keyword '"Hein, Paulo Ricardo Gherardi"' showing total 228 results
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228 results on '"Hein, Paulo Ricardo Gherardi"'

3. Influence of sodium chloride concentration on the dimensional stability of Eucalyptus wood/Influencia da concentracao de cloreto de sodio na estabilidade dimensional da madeira de Eucalyptus

Author

de Sousa Arantes, Lorran, Borges, Ianca Oliveira, Hein, Paulo Ricardo Gherardi, de Oliveira, Barbara Maria Ribeiro Guimaraes, Kuhn, Leonardo Seibert, Carneiro, Daniella Dutra, de Miranda, Larissa Nara Nascimento, do Vale, Hekiciellen Pamella Nunes, Mendes, Lourival Marin, and Guimaraes, Jose Benedito, Jr.

Published
2024
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27. The Inorganic Composition of Tachigali vulgaris Wood: Implications for Bioenergy and Nutrient Balances of Planted Forests in the Amazonia

Author

dos Santos, Elvis Vieira, primary, Lima, Michael Douglas Roque, additional, Dantas, Kelly das Graças Fernandes, additional, Carvalho, Fábio Israel Martins, additional, Gonçalves, Delman de Almeida, additional, Silva, Arystides Resende, additional, Sun, Honggang, additional, Ferreira, Marciel José, additional, Bufalino, Lina, additional, Hein, Paulo Ricardo Gherardi, additional, and Protásio, Thiago de Paula, additional

Published
2023
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28. Planting spacing influences radial variation of basic density and chemical composition of wood from fast growing young Eucalyptus plantations

Author

Pimenta, Emanuella Mesquita, primary, Brito, Emilly Gracielly dos Santos, additional, Gomes, Paola Freitas, additional, Ramalho, Fernanda Maria Guedes, additional, Vidaurre, Graziela Baptista, additional, Couto, Allan Motta, additional, Campoe, Otávio Camargo, additional, and Hein, Paulo Ricardo Gherardi, additional

Published
2023
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30. Phenotyping wood properties of Corymbia torelliana x Corymbia citriodora and Eucalyptus dunnii based on NIR spectra.

Author

Miranda, Leticia, Vagner Tambarussi, Evandro, Abjaud Estopa, Regiane, Maria Guedes Ramalho, Fernanda, Reis Milagres, Flaviana, and Hein, Paulo Ricardo Gherardi

Subjects
WOOD, SULFATE pulping process, TREE breeding, NEAR infrared spectroscopy, EUCALYPTUS, NEAR infrared radiation
Abstract

Selecting individuals in breeding programs for pulp production, the physical and chemical wood traits must be considered in the genotype selection. In this study, trees from hybrid progeny tests of Corymbia torelliana x Corymbia citriodora (CTOxCCT) and progenies of Eucalyptus dunnii (EDU) were investigated. Sawdust of genetically selected standing trees was collected, classified and prepared for near infrared (NIR) spectra readings. The chemical properties of the selected trees were determined through kraft pulping. Predictive models for each property were developed based on the reference data and NIR spectra. Two approaches for models were developed. The first approach, models were fitted with 25 samples of CTOxCCT, and in the second approach, models were fitted using 61 samples (25 of CTOxCCT and 36 of EDU). The estimated R²cv values were 0.60 and 0.73 for basic chip density, 0.37 and 0.65 for extractive contents, 0.56 and 0.53 for total lignin contents, 0.63 and 0.66 for S/G ratio, and 0.52 and 0.77 for screened pulp yield for the first and second approaches, respectively. All developed models have potential for ranking trees in breeding programs. NIR spectroscopy can potentially be applied as a high-throughput field phenotyping tool where thousands of varieties need to be evaluated. [ABSTRACT FROM AUTHOR]

Published
2024
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33. Path analysis and near-infrared spectroscopy in canola crop

Author

Santiago, Alexsandro Carvalho, primary, Pimentel, Guilherme Vieira, additional, Bruzi, Adriano Teodoro, additional, Martins, Inara Alves, additional, Hein, Paulo Ricardo Gherardi, additional, Lima, Michael Douglas Roque, additional, and Pereira, Dyanna Rangel, additional

Published
2023
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35. Hydromechanical behavior of wood during drying studied by NIR spectroscopy and image analysis.

Author

Amaral, Evelize Aparecida, Baliza, Lívia Freire, dos Santos, Luana Maria, Shashiki, André Tetsuo, Trugilho, Paulo Fernando, and Hein, Paulo Ricardo Gherardi

Subjects
LUMBER drying, IMAGE analysis, SPECTRAL imaging, MOISTURE in wood, INHOMOGENEOUS materials, NEAR infrared spectroscopy, NEAR infrared radiation
Abstract

The physical properties of wood are important parameters to qualify the material. However, as it is a heterogeneous material, moisture content and wood contractions may vary within the sample. Thus, the objective was to monitor the hydromechanical behavior of wood during drying using near infrared (NIR) spectroscopy and image analysis. Equidistant points were marked on the radial surface of a wooden board and NIR spectra were recorded at each marking during drying of the piece. After spectral acquisition in each drying step, images were obtained and the markings were referenced to monitor contractions during drying. Moisture content (MC) estimates via NIR spectra showed strong correlation with reference values (R2cv = 0.92, RMSEcv = 9.82 %). From the estimates it was possible to generate graphic images to visualize and quantify the spatial variation of MC and shrinkage during wood drying. In the initial stages of drying, the ends of the material showed high moisture in relation to the center of the sample. However, MC loss was 11 % greater at the ends of the wood board when compared to its interior while the shrinkage in external zones was 3 times greater than the internal part. The use of NIR technique associated with image analysis can be a promising tool for estimating moisture contents and contractions in wood. [ABSTRACT FROM AUTHOR]

Published
2023
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39. Near infrared spectroscopy for estimating properties of kraft paper reinforced with cellulose nanofibrils

Author

Lidiane Costa Lima, Lívia Ribeiro Costa, Ana Márcia Macedo Ladeira Carvalho, Maria Lucia Bianchi, and Hein Paulo Ricardo Gherardi

Subjects
Machine learning, Papermaking, Quality control, Forestry, Mechanical resistance, Nanocellulose
Abstract

Background: The aim of this study was to investigate near infrared (NIR) spectroscopy ability to estimate nanofibril concentration, physical and mechanical properties of Kraft paper reinforced with cellulose nanofibrils (CNF). For this purpose, paper sheets were prepared by mixing unbleached Eucalyptus fibers and cellulose nanofibrils. Twelve treatments result from the combination of the nominal grammages 75, 85, 95 and 105 g m-² with the nanofibril concentrations of 1, 5 and 10wt%, with 7 sheets per treatment. NIR spectra measured directly on paper specimens were correlated with physical and mechanical properties values obtained through conventional laboratory analyzes. Results: Principal component analysis (PCA) revealed no separation among specimens related to nanofibril content. Partial least squares regression (PLS-R) models for estimating nanofibril content, tensile index, stretch and resistance to air passage yielded R 2cv ranging from 0.73 to 0.98. Partial least squares - discriminant analysis (PLS-DA) correctly classified up to 93% of the paper specimens both by grammage and nanofibril content using NIR spectra. Conclusion: This approach appears to be suitable for predicting physical and mechanical properties of Kraft papers and can detect cellulose nanofibril content in the cellulose handsheets.

Published
2022
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42. Evaluation of the spatial variation in moisture content inside wood pieces during drying by NIR spectroscopy.

Author

Baliza, Lívia Freire, Silva, Carlos Henrique da, Amaral, Evelize Aparecida, Ramalho, Fernanda Maria Guedes, Trugilho, Paulo Fernando, Sun, Honggang, and Hein, Paulo Ricardo Gherardi

Subjects
MOISTURE in wood, SPATIAL variation, WOOD, MASS spectrometry, WATER masses
Abstract

The moisture content (MC) of wood affects its industrial performance, but it is difficult to monitor spatial variations in MC. Here, a multivariate regression was developed to estimate the MC from near infrared (NIR) spectra and was used to monitor the spatial variation in the MC of wood during air- and oven-drying. The spectra and mass of wood pieces were measured at five stages during drying (at each 20% loss of initial water mass). Wood pieces were dried naturally and oven-dried at 60 °C. Initially, 25 spectra were recorded at equidistant points covering the entire longitudinal × radial surface of the sample. Then, a planing machine was used to access the inside of the wood, and NIR spectra were measured for each new surface, at a total of 100 points spatially distributed within the wood pieces. The wood pieces were analyzed in their original state, and when they had lost 20, 40, 60, and 80% of their initial water mass. An NIR-based regression (R2p = 0.90 and RMSEP = 10.51%) was applied to estimate the MC, and its spatial gradient during drying was then mapped. These analyses revealed the spatial variation in MC within wood pieces during drying. [ABSTRACT FROM AUTHOR]

Published
2023
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43. Cellulose Nanofibrils as Reinforcement in the Process Manufacture of Paper Handsheets.

Author

Costa, Lívia Ribeiro, Silva, Luiz Eduardo, Matos, Lays Camila, Tonoli, Gustavo Henrique Denzin, and Hein, Paulo Ricardo Gherardi

Subjects
CELLULOSE fibers, MANUFACTURING processes, PAPERMAKING, CELLULOSE, CRYSTAL whiskers
Abstract

Typical scanning electron microscopy (SEM) micrographs obtained for cellulose nanofibrils (a), paper handsheets surface without CNF addition (b) and with 10% CNF (c) Cellulose nanofibrils used as reinforcement go through the fibrillation process in equipment that have discs with grooves on the surfaces against which the pulp is exposed to cyclical and sequential stresses. Preparation of paper handsheets (fiber/CNF) CNF were added directly to the cellulose pulp at 0, 2, 5, 8 and 10 wt% proportion before forming the paper handsheets. Box-plot for tensile index (a), tearing index (b), bursting index (c), stretch (d) and modulus of elasticity (e) in paper handsheets with the addition of different amounts of nanofibrils Figure 6 shows the variations of tensile (a), tearing (b), and bursting (c) indexes, and stretch (d) and modulus of elasticity (e) of cellulose paper handsheets due the addition of different CNF contents. Keywords: Composite fibers; kraft paper; mechanical properties; cellulose microfibrils (CMF); nanocellulose; papermaking; ; ; ; (CMF); ; EN Composite fibers kraft paper mechanical properties cellulose microfibrils (CMF) nanocellulose papermaking ZH (CMF) 7818 7833 16 11/21/22 20221220 NES 221220 GRAPHICAL ABSTRACT Graph Introduction Cellulose nanofibrils (CNF) or cellulose microfibrils (CMF) are known to present unique properties such as high strength and stiffness and to enable numerous applications such as reinforcement material in composites and paper (Osong, Norgren, and Engstrand [21]). [Extracted from the article]

Published
2022
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45. Variations in heartwood formation and wood density as a function of age and plant spacing in a fast-growing eucalyptus plantation

Author

Santos, Lourdes Maria Hilgert, primary, Almeida, Maria Naruna Felix de, additional, Silva, João Gabriel Missia da, additional, Vidaurre, Graziela Baptista, additional, Hein, Paulo Ricardo Gherardi, additional, Silva, Gilson Fernandes da, additional, Zanuncio, Antonio José Vinha, additional, Fraga Filho, Clayton Vieira, additional, Campinhos, Eduardo Nogueira, additional, Mafia, Reginaldo Goncalves, additional, Arantes, Marina Donária Chaves, additional, Tomazello-Filho, Mario, additional, Oliveira, Michel Picanço, additional, Rocha, Quinny Soares, additional, Minini, Daniela, additional, Melo, Alexa Barglini de, additional, and Amorim, Gabriela Aguiar, additional

Published
2021
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