Search Results - "Cunha, Alfredo G"

Synthesis of graphite oxide from milled graphite studied by solid-state 13C nuclear magnetic resonance by Vieira, Mariana A., Gonçalves, Gustavo R., Cipriano, Daniel F., Schettino, Miguel A., Silva Filho, Eloi A., Cunha, Alfredo G., Emmerich, Francisco G., Freitas, Jair C.C.

“…In the present work we investigate the influence of the degree of crystallinity of graphite on the production of graphite oxide (GO). Graphite precursors with…”
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NMR investigation on the occurrence of Na species in porous carbons prepared by NaOH activation by Freitas, Jair C.C., Schettino, Miguel A., Cunha, Alfredo G., Emmerich, Francisco G., Bloise, Antonio C., de Azevedo, Eduardo R., Bonagamba, Tito J.

“…A detailed investigation was conducted about the process of alkali activation of charred rice hulls using NaOH. A carbon-rich precursor was initially prepared…”
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Production of high-purity cellulose, cellulose acetate and cellulose-silica composite from babassu coconut shells by Amaral, Heliane R., Cipriano, Daniel F., Santos, Mayara S., Schettino, Miguel A., Ferreti, João V.T., Meirelles, Carla S., Pereira, Vanessa S., Cunha, Alfredo G., Emmerich, Francisco G., Freitas, Jair C.C.

“…•Organosolv cellulose with high-purity was extracted from babassu coconut shells.•Solid-state 13C NMR and SEM were used as the main characterization…”
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Observation of the transformation of silica phytoliths into SiC and SiO2 particles in biomass-derived carbons by using SEM/EDS, Raman spectroscopy, and XRD by Yapuchura, Enrique R., Tartaglia, Rodolfo S., Cunha, Alfredo G., Freitas, Jair C. C., Emmerich, Francisco G.

“…Scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy, Raman spectroscopy, and X-ray diffraction were successfully used to observe the…”
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Recovery of latent fingermarks from brass cartridge cases: Evaluation of developers, analysis of surfaces and internal ballistic effects by Girelli, Carlos M.A., Vieira, Mariana A., Singh, Kulvir, Cunha, Alfredo G., Freitas, Jair C.C., Emmerich, Francisco G.

“…[Display omitted] •Fingermark development techniques for brass cartridge cases/plates were evaluated.•The sequence CA+GB+fluorescent dye (BY40 or Ardrox)…”
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Comparison of practical techniques to develop latent fingermarks on fired and unfired cartridge cases by Girelli, Carlos M.A, Lobo, Bernardo J.M, Cunha, Alfredo G, Freitas, Jair C.C, Emmerich, Francisco G

“…Highlights • We compared techniques to develop latent fingermarks on fired and unfired cartridge cases. • The sequence cyanoacrylate–gun blue–basic yellow 40…”
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Synthesis and characterization of nanostructured iron compounds prepared from the decomposition of iron pentacarbonyl dispersed into carbon materials with varying porosities by Schettino Jr, Miguel A., Cunha, Alfredo G., Nunes, Evaristo, Passamani, Edson C., Freitas, Jair C. C., Emmerich, Francisco G., Morigaki, Milton K.

“…This work describes the production and characterization of carbon-iron nanocomposites obtained from the decomposition of iron pentacarbonyl (Fe(CO) 5 ) mixed…”
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Synthesis of nanostructured iron oxides dispersed in carbon materials and in situ XRD study of the changes caused by thermal treatment by Gonçalves, Gustavo R., Schettino, Miguel A., Morigaki, Milton K., Nunes, Evaristo, Cunha, Alfredo G., Emmerich, Francisco G., Passamani, Edson C., Baggio-Saitovitch, Elisa, Freitas, Jair C. C.

“…Carbon-based magnetic nanocomposites are of large interest for applications in catalysis, magnetic separation, water cleaning, and magnetic resonance imaging,…”
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Solid-State 13C NMR Spectroscopy Applied to the Study of Carbon Blacks and Carbon Deposits Obtained by Plasma Pyrolysis of Natural Gas by Emmerich, Francisco G., Zucolotto, Carlos G., Cipriano, Daniel F., Freitas, Jair C. C., Cunha, Alfredo G.

“…Solid-state 13C nuclear magnetic resonance (NMR) spectroscopy was used in this work to analyze the physical and chemical properties of plasma blacks and carbon…”
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1H low- and high-field NMR study of the effects of plasma treatment on the oil and water fractions in crude heavy oil by Honorato, Hercílio D.A., Silva, Renzo C., Piumbini, Cleiton K., Zucolotto, Carlos G., de Souza, André A., Cunha, Alfredo G., Emmerich, Francisco G., Lacerda, Valdemar, de Castro, Eustáquio V.R., Bonagamba, Tito J., Freitas, Jair C.C.

“…[Display omitted] ► Study of crude and plasma-treated heavy oils naturally containing emulsified water. ► 1H low- and high-field NMR allowed detailed…”
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Kinetics and {sup 13}C NMR study of oxygen incorporation into PVC- and pitch-derived materials by Gisele F. Altoe, Jair C.C. Freitas, Alfredo G. Cunha, Francisco G. Emmerich, Mark E. Smith

“…The kinetics of oxygen incorporation into a PVC-derived material with pitch-like characteristics was studied by isothermal thermogravimetric analysis at…”
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Observation of the transformation of silica phytoliths into SiC and SiO.sub.2 particles in biomass-derived carbons by using SEM/EDS, Raman spectroscopy, and XRD by Yapuchura, Enrique R, Tartaglia, Rodolfo S, Cunha, Alfredo G, Freitas, Jair C. C, Emmerich, Francisco G

“…Scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy, Raman spectroscopy, and X-ray diffraction were successfully used to observe the…”
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Na,Ca-based catalysts supported on activated carbon for synthesis of biodiesel from soybean oil by Faria, Diêgo Nunes, Cipriano, Daniel F., Schettino, Miguel A., Neto, Álvaro C., Cunha, Alfredo G., Freitas, Jair C.C.

“…Different catalysts containing CaO particles dispersed in commercial activated carbon were prepared by wet impregnation followed by heat treatments. The…”
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Study of thermal transformations in Na,Ca-based catalysts supported on activated carbon and their application in the synthesis of biodiesel from soybean oil by Faria, Diêgo Nunes, Cipriano, Daniel F., Schettino, Miguel A., Neto, Álvaro C., Cunha, Alfredo G., Lopes, Thierry R., Freitas, Jair C.C.

“…[Display omitted] •Na,Ca-based catalysts supported on activated carbon were studied.•The catalysts were produced by heat treatments at different…”
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Electrical, optical, and structural properties of thin films with tri-layers of AZO/ZnMgO/AZO grown by filtered vacuum arc deposition by Gontijo, Leonardo C., Cunha, Alfredo G., Nascente, Pedro A.P.

“…► AZO/ZnMgO/AZO tri-layered films were grown by FCAD filtered cathodic arc deposition. ► The films were highly transparent and presented excellent electrical…”
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Multinuclear magnetic resonance study on the occurrence of phosphorus in activated carbons prepared by chemical activation of lignocellulosic residues from the babassu production by Lopes, Thierry R., Cipriano, Daniel F., Gonçalves, Gustavo R., Honorato, Hercílio A., Schettino, Miguel A., Cunha, Alfredo G., Emmerich, Francisco G., Freitas, Jair C.C.

“…[Display omitted] •Phosphorus-containing activated carbons are produced from lignocellulosic waste.•Solid-state NMR with several probe nuclei is used as the…”
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Solid state 27Al NMR and X-ray diffraction study of alumina–carbon composites by Lopes, Thierry R., Gonçalves, Gustavo R., de Barcellos, Ewerton, Schettino, Miguel A., Cunha, Alfredo G., Emmerich, Francisco G., Freitas, Jair C.C.

“…The structural and chemical transformations occurring in alumina–carbon composites upon heat treatment were investigated by using a combination of X-ray…”
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Solid state super(27)Al NMR and X-ray diffraction study of alumina-carbon composites by Lopes, Thierry R, Goncalves, Gustavo R, de Barcellos, Ewerton, Schettino, Miguel A, Cunha, Alfredo G, Emmerich, Francisco G, Freitas, Jair C C

“…The structural and chemical transformations occurring in alumina-carbon composites upon heat treatment were investigated by using a combination of X-ray…”
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Solid-State 13 C NMR Spectroscopy Applied to the Study of Carbon Blacks and Carbon Deposits Obtained by Plasma Pyrolysis of Natural Gas by Freitas, Jair C. C., Cipriano, Daniel F., Zucolotto, Carlos G., Cunha, Alfredo G., Emmerich, Francisco G.

“…Solid-state 13 C nuclear magnetic resonance (NMR) spectroscopy was used in this work to analyze the physical and chemical properties of plasma blacks and…”
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super(1)H low- and high-field NMR study of the effects of plasma treatment on the oil and water fractions in crude heavy oil by Honorato, Hercilio DA, Silva, Renzo C, Piumbini, Cleiton K, Zucolotto, Carlos G, De Souza, Andre A, Cunha, Alfredo G, Emmerich, Francisco G, Lacerda, Valdemar, De Castro, Eustaquio VR, Bonagamba, Tito J, Freitas, Jair CC

“…The chemical and physical properties of a Brazilian heavy oil submitted to plasma treatment were investigated by super(1)H low- and high-field nuclear magnetic…”
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