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6. MESOSTRUCTURAL CHARACTERIZATION OF PHYLLOSTACHYS AUREA BAMBOO USING OPTICAL MICROSCOPY AND DIGITAL IMAGE PROCESSING

Author

Seixas, M., Paciornik, S., Cardoso, D., and Moreira, L.E.

Subjects
optical microscopy, bio-based material, full-culm bamboo, hierarchical graded structure, digital image processing, composites
Abstract

This study investigates the Phyllostachys aurea bamboo mesostructure through optical microscopy and digital image processing. Specimens were produced using a bamboo full-culm with cross-sections sliced from 1, 4, and 6 meters distant from the ground. Digital images captured through light microscopy with the magnification of 200x were digitally processed for the segmentation of sclerenchyma, vessels, parenchyma, and epidermis phases, allowing for the extraction of the material’s anatomical features. Binary images obtained from each phase were produced and, then, measured, showing portions of the constituent phases of P. aurea cross-sections at the bottom, middle, and top parts of the culm, respectively.

Published
2022
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14. Creation of well‐balanced experimental groups for comparative endodontic laboratory studies: a new proposal based on micro‐CT and in silico methods

Author

De‐Deus, G., primary, Simões‐Carvalho, M., additional, Belladonna, F. G., additional, Versiani, M. A., additional, Silva, E. J. N. L., additional, Cavalcante, D. M., additional, Souza, E. M., additional, Johnsen, G. F., additional, Haugen, H. J., additional, and Paciornik, S., additional

Published
2020
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17. A regioselective coating onto microarray channels of bamboo with chitosan-based silver nanoparticles

Author

Ginoble Pandoli, O, Martins, Rs, De Toni KLG, Paciornik, S, Maurício, Mhp, Lima, Rmc, Padilha, Nb, Letichevsky, S, Avillez, Rr, Rodrigues, Ejr, and Ghavami, K

Subjects
Bamboo, Materials science, Scanning electron microscope, Dendrocalamus giganteus, ved/biology.organism_classification_rank.species, 02 engineering and technology, engineering.material, 010402 general chemistry, 01 natural sciences, Silver nanoparticle, law.invention, Chitosan, chemistry.chemical_compound, Silver nanofiller, Bionanocomposite, Colloid and Surface Chemistry, Coating, law, Trisodium citrate, ved/biology, Nanocoating, Regioselective coating, technology, industry, and agriculture, Surfaces and Interfaces, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, chemistry, Chemical engineering, engineering, Electron microscope, 0210 nano-technology, Bamboo, Silver nanofiller, Nanocoating, Bionanocomposite, Regioselective coating, Hybrid bio-based composite, Hybrid bio-based composite
Abstract

In this investigation, bamboo (Dendrocalamus giganteus Munro) timbers were coated selectively into vascular vessel bundles with a potential antimicrobial colloidal solution of silver nanoparticles (Ag-NPs). Electric charge and size of Ag-NPs, with different charged organic ligands (trisodium citrate and chitosan), affect their self-sorting in different anatomical structures of bamboo when submitted up to 20 impregnation cycles through a vacuum system. Physicochemical characterization of Ag-NPs was performed by spectroscopic techniques and electron microscopy. Confocal laser scanning microscopy and scanning electron microscopy were employed to characterize natural bamboo. Qualitative and quantitative determination of the metal coating in bamboo specimens was performed with X-ray microtomography (μCT), energy-dispersive X-ray spectroscopy, and X-ray diffraction. μCT revealed a gradient deposition of citrate-capped Ag-NPs into the parenchyma tissue with the higher concentration at the outer part of the bamboo. On the other hand, the chitosan-capped Ag-NPs were deposited mainly in the vessel bundles.

Published
2019

26. Quantifying Enhanced Oil Recovery in Synthetic Media with MicroCT

Author

Paciornik, S., Scheffer, K., Carvalho, M., Méheust, Yves, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), and Dubigeon, Isabelle

Subjects
[PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], [PHYS.PHYS.PHYS-FLU-DYN] Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn]
Abstract

International audience; Enhanced oil recovery methods are tested and optimized in syntheticmedia, emulating porosity and permeability of real oil-bearing rocks.Such a medium was produced with sintered bi-disperse glass beads andmicroCT images (4 µm resolution) were acquired at different stages offluid motion through the medium. Synthetic seawater with or without oil/water emulsion was used to recover oil previously saturating the medium´spores. The water was doped with KI to fine tune X-ray absorption. Thus,3D images showing the beads, doped water and residual oil presenteda 3-modal histogram. After denoising with a non-local means filter, theimages were segmented and the distribution of residual oil ganglia wasvisualized and quantified. Probability density functions of volumes (~10^4ganglia spanning 8 orders of magnitude) show well defined exponentialbehaviors for the displacement of oil by water, while the use of emulsionsprovides better recovery efficiency with larger numbers of larger ganglia

Published
2018

27. Anatomical danger zone reconsidered: a micro‐ CT study on dentine thickness in mandibular molars

Author

De‐Deus, G., primary, Rodrigues, E. A., additional, Belladonna, F. G., additional, Simões‐Carvalho, M., additional, Cavalcante, D. M., additional, Oliveira, D. S., additional, Souza, E. M., additional, Giorgi, K. A., additional, Versiani, M. A., additional, Lopes, R. T., additional, Silva, E. J. N. L., additional, and Paciornik, S., additional

Published
2019
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30. Chemical induced demineralization study in cortical bone

Author

Sales, E., primary, Silva, C.E.R. da, additional, Letichevsky, S., additional, Santos, R. dos, additional, Leitao, R., additional, Santos, C.T. dos, additional, de Oliveira, L.F., additional, de Avillez, R., additional, Monteiro, M., additional, Costa-Felix, R., additional, Paciornik, S., additional, and Anjos, M. dos, additional

Published
2018
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35. Gold nanoparticles on the surface of soda-lime glass : morphological, linear and nonlinear optical characterization

Author

Romani, E. C., Vitoreti, Douglas, Gouvea, Paula M. P., Caldas, P. G., Prioli, R., Paciornik, S., Fokine, Michael, Braga, Arthur M. B., Gomes, Anderson S. L., Carvalho, Isabel C. S., Romani, E. C., Vitoreti, Douglas, Gouvea, Paula M. P., Caldas, P. G., Prioli, R., Paciornik, S., Fokine, Michael, Braga, Arthur M. B., Gomes, Anderson S. L., and Carvalho, Isabel C. S.

Abstract

Materials presenting high optical nonlinearity, such as materials containing metal nanoparticles (NPs), can be used in various applications in photonics. This motivated the research presented in this paper, where morphological, linear and nonlinear optical characteristics of gold NPs on the surface of bulk soda-lime glass substrates were investigated as a function of nanoparticle height. The NPs were obtained by annealing gold (Au) thin films previously deposited on the substrates. Pixel intensity histogram fitting on Atomic Force Microscopy (AFM) images was performed to obtain the thickness of the deposited film. Image analysis was employed to obtain the statistical distribution of the average height of the NPs. In addition, absorbance spectra of the samples before and after annealing were measured. Finally, the nonlinear refractive index (n(2))and the nonlinear absorption index (alpha 2) at 800 nm were obtained before and after annealing by using the thermally managed eclipse Z-scan (TM-EZ) technique with a Ti: Sapphire laser (150 fs pulses). Results show that both n2 and alpha 2 at this wavelength change signs after the annealing and that the samples presented a high nonlinear refractive index., QC 20120418

Published
2012
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36. Longitudinal co-site optical microscopy study on the chelating ability of etidronate and EDTA using a comparative single-tooth model

Author

De-Deus, G, Zehnder, Matthias; https://orcid.org/0000-0001-9545-7828, Reis, C, Fidel, S, Fidel, R A S, Galan, J, Paciornik, S, De-Deus, G, Zehnder, Matthias; https://orcid.org/0000-0001-9545-7828, Reis, C, Fidel, S, Fidel, R A S, Galan, J, and Paciornik, S

Abstract

In the present study the smear layer dissolution kinetics of 18% etidronate (HEBP), 9% HEBP, and 17% ethylenediaminetetraacetic acid (EDTA) on human dentin were quantitatively and longitudinally analyzed by using a single-tooth comparative model. Coronal dentin disks were prepared from 3 maxillary human molars. A standardized smear layer was produced on the pulpal side of each disk. The smear layer-covered surface was divided into 3 similar areas. Each of these was then exposed to 1 of the 3 irrigants under investigation, whereas the others were covered with adhesive tape. Co-site image sequences of the areas under investigation were obtained after several cumulative demineralization times. Sixteen images were obtained from each dentin area of each tooth for each experimental time at 1000x magnification. An image processing and analysis sequence measured sets of images, providing data of area fraction for thousands of tubules over time and allowing us to quantitatively follow the effect of the chelating substances. The Kruskal-Wallis H test and Dunn multiple comparison test were used to analyze the data. Overall, it can be concluded that the demineralization kinetics promoted by both 9% HEBP and 18% HEBP were significantly slower than those of 17% EDTA (P < .05). In addition, the single-tooth model is advantageous over the first co-site optical microscopy dentin assessments when different chelator solutions are compared.

Published
2008

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