Portal do Governo Brasileiro
BDPA - Bases de Dados da Pesquisa Agropecuária Embrapa
 






Registro Completo
Biblioteca(s):  Embrapa Florestas.
Data corrente:  08/06/2017
Data da última atualização:  11/07/2017
Tipo da produção científica:  Artigo em Periódico Indexado
Autoria:  CADEMARTORI, P. H. G. de; STAFFORD, L.; BLANCHET, P.; MAGALHAES, W. L. E.; BOLZON DE MUNIZ, G. I.
Afiliação:  Pedro Henrique Gonzalez de Cademartori, Doutorando da UFPR; Luc Stafford, Departement de Physique, Universite de Montreal; Pierre Blanchet, NSERC; WASHINGTON LUIZ ESTEVES MAGALHAES, CNPF; Graciela Ines Bolzon de Muniz, UFPR.
Título:  Enhancing the water repellency of wood surfaces by atmospheric pressure cold plasma deposition of fluorocarbon film.
Ano de publicação:  2017
Fonte/Imprenta:  RSC Advances, v. 7, n. 46, p. 29159-29169, Jun. 2017.
DOI:  10.1039/c7ra03334f
Idioma:  Inglês
Conteúdo:  In this study, fluorocarbon thin filmsweredepositedonthe surfaceofwhite spruce andBrazilian cedarwoods via atmospheric pressure dielectric barrier discharge in the afterglow mode with octafluoropropane gas. A pretreatment with oxygen plasma was introduced before the thin film deposition to determine if this plasma condition could increase the wood nano/micro roughness, helping to improve the hydrophobicity of the surface. The optimal conditions of water repellency for both woods were examined in terms of their resistance to aging in controlled conditions. The water contact angle measurements showed a hydrophobic surface with a stable angle for both woods. X-ray photoelectron spectroscopy reveals the presence of CF, CF2 and CF3 functional groups after the Ar/C3F8 plasma, especially for longer treatments. The open-air system of the plasma reactor leads to the simultaneous fluorination and incorporation of oxygen-containing groups. The pre-treatment of oxygen plasma increases the wood roughness; however, the chemical attachment of oxygen molecules is more significant, negatively affecting the degree of repellency of the plasma-coated woods. On the other hand, the fluorocarbon deposition increases the wood roughness and creates a hydrophobic surface simultaneously. Even with partial defluorination after aging, both plasma-coated woods retain a similar degree of water repellency, which partially avoid chemical reorganization of their surface due to environmental exposure.
Palavras-Chave:  Atmospheric plasma; Filme de fluorcarbono; Hydrophobic surface; Molhabilidade; Plasma a frio; Plasma atmosférico; Plasma treatment; Superfície hidrofóbica; Surface modification; Wetting.
Thesagro:  Madeira.
Thesaurus Nal:  Wood treatment.
Categoria do assunto:  X Pesquisa, Tecnologia e Engenharia
URL:  https://ainfo.cnptia.embrapa.br/digital/bitstream/item/160655/1/2017-Washington-RCSA-Enhancing.pdf
Marc:  Mostrar Marc Completo
Registro original:  Embrapa Florestas (CNPF)
Biblioteca ID Origem Tipo/Formato Classificação Cutter Registro Volume Status URL
CNPF55822 - 1UPCAP - DD
Voltar






Registro Completo

Biblioteca(s):  Embrapa Agricultura Digital.
Data corrente:  24/08/2022
Data da última atualização:  25/08/2022
Tipo da produção científica:  Artigo em Periódico Indexado
Circulação/Nível:  B - 3
Autoria:  SANTOS, L. T. dos; WERNER, J. P. S.; REIS, A. A. dos; TORO, A. P. G.; ANTUNES, J. F. G.; COUTINHO, A. C.; LAMPARELLI, R. A. C.; MAGALHÃES, P. S. G.; ESQUERDO, J. C. D. M.; FIGUEIREDO, G. K. D. A.
Afiliação:  FEAGRI/UNICAMP; FEAGRI/UNICAMP; UNICAMP; FEAGRI/UNICAMP; JOAO FRANCISCO GONCALVES ANTUNES, CNPTIA; ALEXANDRE CAMARGO COUTINHO, CNPTIA; UNICAMP; UNICAMP; JULIO CESAR DALLA MORA ESQUERDO, CNPTIA, FEAGRI/UNICAMP; FEAGRI/UNICAMP.
Título:  Multitemporal segmentation of Sentinel-2 images in an agricultural intensification region in Brazil.
Ano de publicação:  2022
Fonte/Imprenta:  ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, v. V-3-2022, p. 389-395, 2022.
DOI:  https://doi.org/10.5194/isprs-annals-V-3-2022-389-2022
Idioma:  Inglês
Notas:  Edition of proceedings of the 2022 edition of the XXIVth ISPRS Congress, Nice, France.
Conteúdo:  ABSTRACT: With the recent evolution in the sensor's spatial resolution, such as the MultiSpectral Imager (MSI) of the Sentinel-2 mission, the need to use segmentation techniques in satellite images has increased. Although the advantages of image segmentation to delineate agricultural fields in images are already known, the literature shows that it is rarely used to consider temporal changes in highly managed regions with the intensification of agricultural activities. Therefore, this work aimed to evaluate a multitemporal segmentation method based on the coefficient of variation of spectral bands and vegetation indices obtained from Sentinel-2 images, considering two agricultural years (2018-2019 and 2019-2020) in an area with agricultural intensification. Images of the coefficient of variation represented the spectro-temporal dynamics within the study area. These images were also used to apply an edge detection filter (Sobel) to verify their performance. The region-based algorithm Watershed Segmentation (WS) was used in the segmentation process. Subsequently, to assess the quality of the segmentation results produced, the metrics Potential Segmentation Error (PSE), Number-of-Segments Ratio (NSR), and Euclidean Distance 2 (ED2) were calculated from manually delineated reference objects. The segmentation achieved its best performance when applied to the unfiltered coefficient of variation images of spectral bands with an ED2 equal to 7.289 and 2.529 for 2018-2019 and 2019-202... Mostrar Tudo
Palavras-Chave:  AssesSeg; Coefficient of variation; Coeficiente de variação; Detecção de bordas; Edge detection; Índice de vegetação; Intensificação agrícola; OBIA; Segmentação de bacias hidrográficas; Sobel; Watershed segmentation.
Thesaurus NAL:  Vegetation index.
Categoria do assunto:  --
URL:  https://ainfo.cnptia.embrapa.br/digital/bitstream/doc/1145716/1/AP-Multitemporal-segmentation-Sentinel2-2022.pdf
Marc:  Mostrar Marc Completo
Registro original:  Embrapa Agricultura Digital (CNPTIA)
Biblioteca ID Origem Tipo/Formato Classificação Cutter Registro Volume Status
CNPTIA21241 - 1UPCAP - DD
Fechar
Nenhum registro encontrado para a expressão de busca informada.
 
 

Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área Restrita

Embrapa Agricultura Digital
Av. André Tosello, 209 - Barão Geraldo
Caixa Postal 6041- 13083-886 - Campinas, SP
SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional